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1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  linux/fs/ext4/super.c
4  *
5  * Copyright (C) 1992, 1993, 1994, 1995
6  * Remy Card (card@masi.ibp.fr)
7  * Laboratoire MASI - Institut Blaise Pascal
8  * Universite Pierre et Marie Curie (Paris VI)
9  *
10  *  from
11  *
12  *  linux/fs/minix/inode.c
13  *
14  *  Copyright (C) 1991, 1992  Linus Torvalds
15  *
16  *  Big-endian to little-endian byte-swapping/bitmaps by
17  *        David S. Miller (davem@caip.rutgers.edu), 1995
18  */
19 
20 #include <linux/module.h>
21 #include <linux/string.h>
22 #include <linux/fs.h>
23 #include <linux/time.h>
24 #include <linux/vmalloc.h>
25 #include <linux/slab.h>
26 #include <linux/init.h>
27 #include <linux/blkdev.h>
28 #include <linux/backing-dev.h>
29 #include <linux/parser.h>
30 #include <linux/buffer_head.h>
31 #include <linux/exportfs.h>
32 #include <linux/vfs.h>
33 #include <linux/random.h>
34 #include <linux/mount.h>
35 #include <linux/namei.h>
36 #include <linux/quotaops.h>
37 #include <linux/seq_file.h>
38 #include <linux/ctype.h>
39 #include <linux/log2.h>
40 #include <linux/crc16.h>
41 #include <linux/dax.h>
42 #include <linux/cleancache.h>
43 #include <linux/uaccess.h>
44 #include <linux/iversion.h>
45 #include <linux/unicode.h>
46 #include <linux/part_stat.h>
47 #include <linux/kthread.h>
48 #include <linux/freezer.h>
49 #include <linux/fsnotify.h>
50 #include <linux/fs_context.h>
51 #include <linux/fs_parser.h>
52 
53 #include "ext4.h"
54 #include "ext4_extents.h"	/* Needed for trace points definition */
55 #include "ext4_jbd2.h"
56 #include "xattr.h"
57 #include "acl.h"
58 #include "mballoc.h"
59 #include "fsmap.h"
60 
61 #define CREATE_TRACE_POINTS
62 #include <trace/events/ext4.h>
63 
64 static struct ext4_lazy_init *ext4_li_info;
65 static DEFINE_MUTEX(ext4_li_mtx);
66 static struct ratelimit_state ext4_mount_msg_ratelimit;
67 
68 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
69 			     unsigned long journal_devnum);
70 static int ext4_show_options(struct seq_file *seq, struct dentry *root);
71 static void ext4_update_super(struct super_block *sb);
72 static int ext4_commit_super(struct super_block *sb);
73 static int ext4_mark_recovery_complete(struct super_block *sb,
74 					struct ext4_super_block *es);
75 static int ext4_clear_journal_err(struct super_block *sb,
76 				  struct ext4_super_block *es);
77 static int ext4_sync_fs(struct super_block *sb, int wait);
78 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
79 static int ext4_unfreeze(struct super_block *sb);
80 static int ext4_freeze(struct super_block *sb);
81 static inline int ext2_feature_set_ok(struct super_block *sb);
82 static inline int ext3_feature_set_ok(struct super_block *sb);
83 static void ext4_destroy_lazyinit_thread(void);
84 static void ext4_unregister_li_request(struct super_block *sb);
85 static void ext4_clear_request_list(void);
86 static struct inode *ext4_get_journal_inode(struct super_block *sb,
87 					    unsigned int journal_inum);
88 static int ext4_validate_options(struct fs_context *fc);
89 static int ext4_check_opt_consistency(struct fs_context *fc,
90 				      struct super_block *sb);
91 static void ext4_apply_options(struct fs_context *fc, struct super_block *sb);
92 static int ext4_parse_param(struct fs_context *fc, struct fs_parameter *param);
93 static int ext4_get_tree(struct fs_context *fc);
94 static int ext4_reconfigure(struct fs_context *fc);
95 static void ext4_fc_free(struct fs_context *fc);
96 static int ext4_init_fs_context(struct fs_context *fc);
97 static void ext4_kill_sb(struct super_block *sb);
98 static const struct fs_parameter_spec ext4_param_specs[];
99 
100 /*
101  * Lock ordering
102  *
103  * page fault path:
104  * mmap_lock -> sb_start_pagefault -> invalidate_lock (r) -> transaction start
105  *   -> page lock -> i_data_sem (rw)
106  *
107  * buffered write path:
108  * sb_start_write -> i_mutex -> mmap_lock
109  * sb_start_write -> i_mutex -> transaction start -> page lock ->
110  *   i_data_sem (rw)
111  *
112  * truncate:
113  * sb_start_write -> i_mutex -> invalidate_lock (w) -> i_mmap_rwsem (w) ->
114  *   page lock
115  * sb_start_write -> i_mutex -> invalidate_lock (w) -> transaction start ->
116  *   i_data_sem (rw)
117  *
118  * direct IO:
119  * sb_start_write -> i_mutex -> mmap_lock
120  * sb_start_write -> i_mutex -> transaction start -> i_data_sem (rw)
121  *
122  * writepages:
123  * transaction start -> page lock(s) -> i_data_sem (rw)
124  */
125 
126 static const struct fs_context_operations ext4_context_ops = {
127 	.parse_param	= ext4_parse_param,
128 	.get_tree	= ext4_get_tree,
129 	.reconfigure	= ext4_reconfigure,
130 	.free		= ext4_fc_free,
131 };
132 
133 
134 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
135 static struct file_system_type ext2_fs_type = {
136 	.owner			= THIS_MODULE,
137 	.name			= "ext2",
138 	.init_fs_context	= ext4_init_fs_context,
139 	.parameters		= ext4_param_specs,
140 	.kill_sb		= ext4_kill_sb,
141 	.fs_flags		= FS_REQUIRES_DEV,
142 };
143 MODULE_ALIAS_FS("ext2");
144 MODULE_ALIAS("ext2");
145 #define IS_EXT2_SB(sb) ((sb)->s_type == &ext2_fs_type)
146 #else
147 #define IS_EXT2_SB(sb) (0)
148 #endif
149 
150 
151 static struct file_system_type ext3_fs_type = {
152 	.owner			= THIS_MODULE,
153 	.name			= "ext3",
154 	.init_fs_context	= ext4_init_fs_context,
155 	.parameters		= ext4_param_specs,
156 	.kill_sb		= ext4_kill_sb,
157 	.fs_flags		= FS_REQUIRES_DEV,
158 };
159 MODULE_ALIAS_FS("ext3");
160 MODULE_ALIAS("ext3");
161 #define IS_EXT3_SB(sb) ((sb)->s_type == &ext3_fs_type)
162 
163 
__ext4_read_bh(struct buffer_head * bh,blk_opf_t op_flags,bh_end_io_t * end_io)164 static inline void __ext4_read_bh(struct buffer_head *bh, blk_opf_t op_flags,
165 				  bh_end_io_t *end_io)
166 {
167 	/*
168 	 * buffer's verified bit is no longer valid after reading from
169 	 * disk again due to write out error, clear it to make sure we
170 	 * recheck the buffer contents.
171 	 */
172 	clear_buffer_verified(bh);
173 
174 	bh->b_end_io = end_io ? end_io : end_buffer_read_sync;
175 	get_bh(bh);
176 	submit_bh(REQ_OP_READ | op_flags, bh);
177 }
178 
ext4_read_bh_nowait(struct buffer_head * bh,blk_opf_t op_flags,bh_end_io_t * end_io)179 void ext4_read_bh_nowait(struct buffer_head *bh, blk_opf_t op_flags,
180 			 bh_end_io_t *end_io)
181 {
182 	BUG_ON(!buffer_locked(bh));
183 
184 	if (ext4_buffer_uptodate(bh)) {
185 		unlock_buffer(bh);
186 		return;
187 	}
188 	__ext4_read_bh(bh, op_flags, end_io);
189 }
190 
ext4_read_bh(struct buffer_head * bh,blk_opf_t op_flags,bh_end_io_t * end_io)191 int ext4_read_bh(struct buffer_head *bh, blk_opf_t op_flags, bh_end_io_t *end_io)
192 {
193 	BUG_ON(!buffer_locked(bh));
194 
195 	if (ext4_buffer_uptodate(bh)) {
196 		unlock_buffer(bh);
197 		return 0;
198 	}
199 
200 	__ext4_read_bh(bh, op_flags, end_io);
201 
202 	wait_on_buffer(bh);
203 	if (buffer_uptodate(bh))
204 		return 0;
205 	return -EIO;
206 }
207 
ext4_read_bh_lock(struct buffer_head * bh,blk_opf_t op_flags,bool wait)208 int ext4_read_bh_lock(struct buffer_head *bh, blk_opf_t op_flags, bool wait)
209 {
210 	lock_buffer(bh);
211 	if (!wait) {
212 		ext4_read_bh_nowait(bh, op_flags, NULL);
213 		return 0;
214 	}
215 	return ext4_read_bh(bh, op_flags, NULL);
216 }
217 
218 /*
219  * This works like __bread_gfp() except it uses ERR_PTR for error
220  * returns.  Currently with sb_bread it's impossible to distinguish
221  * between ENOMEM and EIO situations (since both result in a NULL
222  * return.
223  */
__ext4_sb_bread_gfp(struct super_block * sb,sector_t block,blk_opf_t op_flags,gfp_t gfp)224 static struct buffer_head *__ext4_sb_bread_gfp(struct super_block *sb,
225 					       sector_t block,
226 					       blk_opf_t op_flags, gfp_t gfp)
227 {
228 	struct buffer_head *bh;
229 	int ret;
230 
231 	bh = sb_getblk_gfp(sb, block, gfp);
232 	if (bh == NULL)
233 		return ERR_PTR(-ENOMEM);
234 	if (ext4_buffer_uptodate(bh))
235 		return bh;
236 
237 	ret = ext4_read_bh_lock(bh, REQ_META | op_flags, true);
238 	if (ret) {
239 		put_bh(bh);
240 		return ERR_PTR(ret);
241 	}
242 	return bh;
243 }
244 
ext4_sb_bread(struct super_block * sb,sector_t block,blk_opf_t op_flags)245 struct buffer_head *ext4_sb_bread(struct super_block *sb, sector_t block,
246 				   blk_opf_t op_flags)
247 {
248 	return __ext4_sb_bread_gfp(sb, block, op_flags, __GFP_MOVABLE);
249 }
250 
ext4_sb_bread_unmovable(struct super_block * sb,sector_t block)251 struct buffer_head *ext4_sb_bread_unmovable(struct super_block *sb,
252 					    sector_t block)
253 {
254 	return __ext4_sb_bread_gfp(sb, block, 0, 0);
255 }
256 
ext4_sb_breadahead_unmovable(struct super_block * sb,sector_t block)257 void ext4_sb_breadahead_unmovable(struct super_block *sb, sector_t block)
258 {
259 	struct buffer_head *bh = sb_getblk_gfp(sb, block, 0);
260 
261 	if (likely(bh)) {
262 		if (trylock_buffer(bh))
263 			ext4_read_bh_nowait(bh, REQ_RAHEAD, NULL);
264 		brelse(bh);
265 	}
266 }
267 
ext4_verify_csum_type(struct super_block * sb,struct ext4_super_block * es)268 static int ext4_verify_csum_type(struct super_block *sb,
269 				 struct ext4_super_block *es)
270 {
271 	if (!ext4_has_feature_metadata_csum(sb))
272 		return 1;
273 
274 	return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
275 }
276 
ext4_superblock_csum(struct super_block * sb,struct ext4_super_block * es)277 __le32 ext4_superblock_csum(struct super_block *sb,
278 			    struct ext4_super_block *es)
279 {
280 	struct ext4_sb_info *sbi = EXT4_SB(sb);
281 	int offset = offsetof(struct ext4_super_block, s_checksum);
282 	__u32 csum;
283 
284 	csum = ext4_chksum(sbi, ~0, (char *)es, offset);
285 
286 	return cpu_to_le32(csum);
287 }
288 
ext4_superblock_csum_verify(struct super_block * sb,struct ext4_super_block * es)289 static int ext4_superblock_csum_verify(struct super_block *sb,
290 				       struct ext4_super_block *es)
291 {
292 	if (!ext4_has_metadata_csum(sb))
293 		return 1;
294 
295 	return es->s_checksum == ext4_superblock_csum(sb, es);
296 }
297 
ext4_superblock_csum_set(struct super_block * sb)298 void ext4_superblock_csum_set(struct super_block *sb)
299 {
300 	struct ext4_super_block *es = EXT4_SB(sb)->s_es;
301 
302 	if (!ext4_has_metadata_csum(sb))
303 		return;
304 
305 	es->s_checksum = ext4_superblock_csum(sb, es);
306 }
307 
ext4_block_bitmap(struct super_block * sb,struct ext4_group_desc * bg)308 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
309 			       struct ext4_group_desc *bg)
310 {
311 	return le32_to_cpu(bg->bg_block_bitmap_lo) |
312 		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
313 		 (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
314 }
315 
ext4_inode_bitmap(struct super_block * sb,struct ext4_group_desc * bg)316 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
317 			       struct ext4_group_desc *bg)
318 {
319 	return le32_to_cpu(bg->bg_inode_bitmap_lo) |
320 		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
321 		 (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
322 }
323 
ext4_inode_table(struct super_block * sb,struct ext4_group_desc * bg)324 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
325 			      struct ext4_group_desc *bg)
326 {
327 	return le32_to_cpu(bg->bg_inode_table_lo) |
328 		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
329 		 (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
330 }
331 
ext4_free_group_clusters(struct super_block * sb,struct ext4_group_desc * bg)332 __u32 ext4_free_group_clusters(struct super_block *sb,
333 			       struct ext4_group_desc *bg)
334 {
335 	return le16_to_cpu(bg->bg_free_blocks_count_lo) |
336 		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
337 		 (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
338 }
339 
ext4_free_inodes_count(struct super_block * sb,struct ext4_group_desc * bg)340 __u32 ext4_free_inodes_count(struct super_block *sb,
341 			      struct ext4_group_desc *bg)
342 {
343 	return le16_to_cpu(bg->bg_free_inodes_count_lo) |
344 		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
345 		 (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
346 }
347 
ext4_used_dirs_count(struct super_block * sb,struct ext4_group_desc * bg)348 __u32 ext4_used_dirs_count(struct super_block *sb,
349 			      struct ext4_group_desc *bg)
350 {
351 	return le16_to_cpu(bg->bg_used_dirs_count_lo) |
352 		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
353 		 (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
354 }
355 
ext4_itable_unused_count(struct super_block * sb,struct ext4_group_desc * bg)356 __u32 ext4_itable_unused_count(struct super_block *sb,
357 			      struct ext4_group_desc *bg)
358 {
359 	return le16_to_cpu(bg->bg_itable_unused_lo) |
360 		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
361 		 (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
362 }
363 
ext4_block_bitmap_set(struct super_block * sb,struct ext4_group_desc * bg,ext4_fsblk_t blk)364 void ext4_block_bitmap_set(struct super_block *sb,
365 			   struct ext4_group_desc *bg, ext4_fsblk_t blk)
366 {
367 	bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
368 	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
369 		bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
370 }
371 
ext4_inode_bitmap_set(struct super_block * sb,struct ext4_group_desc * bg,ext4_fsblk_t blk)372 void ext4_inode_bitmap_set(struct super_block *sb,
373 			   struct ext4_group_desc *bg, ext4_fsblk_t blk)
374 {
375 	bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
376 	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
377 		bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
378 }
379 
ext4_inode_table_set(struct super_block * sb,struct ext4_group_desc * bg,ext4_fsblk_t blk)380 void ext4_inode_table_set(struct super_block *sb,
381 			  struct ext4_group_desc *bg, ext4_fsblk_t blk)
382 {
383 	bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
384 	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
385 		bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
386 }
387 
ext4_free_group_clusters_set(struct super_block * sb,struct ext4_group_desc * bg,__u32 count)388 void ext4_free_group_clusters_set(struct super_block *sb,
389 				  struct ext4_group_desc *bg, __u32 count)
390 {
391 	bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
392 	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
393 		bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
394 }
395 
ext4_free_inodes_set(struct super_block * sb,struct ext4_group_desc * bg,__u32 count)396 void ext4_free_inodes_set(struct super_block *sb,
397 			  struct ext4_group_desc *bg, __u32 count)
398 {
399 	bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
400 	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
401 		bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
402 }
403 
ext4_used_dirs_set(struct super_block * sb,struct ext4_group_desc * bg,__u32 count)404 void ext4_used_dirs_set(struct super_block *sb,
405 			  struct ext4_group_desc *bg, __u32 count)
406 {
407 	bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
408 	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
409 		bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
410 }
411 
ext4_itable_unused_set(struct super_block * sb,struct ext4_group_desc * bg,__u32 count)412 void ext4_itable_unused_set(struct super_block *sb,
413 			  struct ext4_group_desc *bg, __u32 count)
414 {
415 	bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
416 	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
417 		bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
418 }
419 
__ext4_update_tstamp(__le32 * lo,__u8 * hi,time64_t now)420 static void __ext4_update_tstamp(__le32 *lo, __u8 *hi, time64_t now)
421 {
422 	now = clamp_val(now, 0, (1ull << 40) - 1);
423 
424 	*lo = cpu_to_le32(lower_32_bits(now));
425 	*hi = upper_32_bits(now);
426 }
427 
__ext4_get_tstamp(__le32 * lo,__u8 * hi)428 static time64_t __ext4_get_tstamp(__le32 *lo, __u8 *hi)
429 {
430 	return ((time64_t)(*hi) << 32) + le32_to_cpu(*lo);
431 }
432 #define ext4_update_tstamp(es, tstamp) \
433 	__ext4_update_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi, \
434 			     ktime_get_real_seconds())
435 #define ext4_get_tstamp(es, tstamp) \
436 	__ext4_get_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi)
437 
438 #define EXT4_SB_REFRESH_INTERVAL_SEC (3600) /* seconds (1 hour) */
439 #define EXT4_SB_REFRESH_INTERVAL_KB (16384) /* kilobytes (16MB) */
440 
441 /*
442  * The ext4_maybe_update_superblock() function checks and updates the
443  * superblock if needed.
444  *
445  * This function is designed to update the on-disk superblock only under
446  * certain conditions to prevent excessive disk writes and unnecessary
447  * waking of the disk from sleep. The superblock will be updated if:
448  * 1. More than an hour has passed since the last superblock update, and
449  * 2. More than 16MB have been written since the last superblock update.
450  *
451  * @sb: The superblock
452  */
ext4_maybe_update_superblock(struct super_block * sb)453 static void ext4_maybe_update_superblock(struct super_block *sb)
454 {
455 	struct ext4_sb_info *sbi = EXT4_SB(sb);
456 	struct ext4_super_block *es = sbi->s_es;
457 	journal_t *journal = sbi->s_journal;
458 	time64_t now;
459 	__u64 last_update;
460 	__u64 lifetime_write_kbytes;
461 	__u64 diff_size;
462 
463 	if (sb_rdonly(sb) || !(sb->s_flags & SB_ACTIVE) ||
464 	    !journal || (journal->j_flags & JBD2_UNMOUNT))
465 		return;
466 
467 	now = ktime_get_real_seconds();
468 	last_update = ext4_get_tstamp(es, s_wtime);
469 
470 	if (likely(now - last_update < EXT4_SB_REFRESH_INTERVAL_SEC))
471 		return;
472 
473 	lifetime_write_kbytes = sbi->s_kbytes_written +
474 		((part_stat_read(sb->s_bdev, sectors[STAT_WRITE]) -
475 		  sbi->s_sectors_written_start) >> 1);
476 
477 	/* Get the number of kilobytes not written to disk to account
478 	 * for statistics and compare with a multiple of 16 MB. This
479 	 * is used to determine when the next superblock commit should
480 	 * occur (i.e. not more often than once per 16MB if there was
481 	 * less written in an hour).
482 	 */
483 	diff_size = lifetime_write_kbytes - le64_to_cpu(es->s_kbytes_written);
484 
485 	if (diff_size > EXT4_SB_REFRESH_INTERVAL_KB)
486 		schedule_work(&EXT4_SB(sb)->s_sb_upd_work);
487 }
488 
489 /*
490  * The del_gendisk() function uninitializes the disk-specific data
491  * structures, including the bdi structure, without telling anyone
492  * else.  Once this happens, any attempt to call mark_buffer_dirty()
493  * (for example, by ext4_commit_super), will cause a kernel OOPS.
494  * This is a kludge to prevent these oops until we can put in a proper
495  * hook in del_gendisk() to inform the VFS and file system layers.
496  */
block_device_ejected(struct super_block * sb)497 static int block_device_ejected(struct super_block *sb)
498 {
499 	struct inode *bd_inode = sb->s_bdev->bd_inode;
500 	struct backing_dev_info *bdi = inode_to_bdi(bd_inode);
501 
502 	return bdi->dev == NULL;
503 }
504 
ext4_journal_commit_callback(journal_t * journal,transaction_t * txn)505 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
506 {
507 	struct super_block		*sb = journal->j_private;
508 	struct ext4_sb_info		*sbi = EXT4_SB(sb);
509 	int				error = is_journal_aborted(journal);
510 	struct ext4_journal_cb_entry	*jce;
511 
512 	BUG_ON(txn->t_state == T_FINISHED);
513 
514 	ext4_process_freed_data(sb, txn->t_tid);
515 	ext4_maybe_update_superblock(sb);
516 
517 	spin_lock(&sbi->s_md_lock);
518 	while (!list_empty(&txn->t_private_list)) {
519 		jce = list_entry(txn->t_private_list.next,
520 				 struct ext4_journal_cb_entry, jce_list);
521 		list_del_init(&jce->jce_list);
522 		spin_unlock(&sbi->s_md_lock);
523 		jce->jce_func(sb, jce, error);
524 		spin_lock(&sbi->s_md_lock);
525 	}
526 	spin_unlock(&sbi->s_md_lock);
527 }
528 
529 /*
530  * This writepage callback for write_cache_pages()
531  * takes care of a few cases after page cleaning.
532  *
533  * write_cache_pages() already checks for dirty pages
534  * and calls clear_page_dirty_for_io(), which we want,
535  * to write protect the pages.
536  *
537  * However, we may have to redirty a page (see below.)
538  */
ext4_journalled_writepage_callback(struct folio * folio,struct writeback_control * wbc,void * data)539 static int ext4_journalled_writepage_callback(struct folio *folio,
540 					      struct writeback_control *wbc,
541 					      void *data)
542 {
543 	transaction_t *transaction = (transaction_t *) data;
544 	struct buffer_head *bh, *head;
545 	struct journal_head *jh;
546 
547 	bh = head = folio_buffers(folio);
548 	do {
549 		/*
550 		 * We have to redirty a page in these cases:
551 		 * 1) If buffer is dirty, it means the page was dirty because it
552 		 * contains a buffer that needs checkpointing. So the dirty bit
553 		 * needs to be preserved so that checkpointing writes the buffer
554 		 * properly.
555 		 * 2) If buffer is not part of the committing transaction
556 		 * (we may have just accidentally come across this buffer because
557 		 * inode range tracking is not exact) or if the currently running
558 		 * transaction already contains this buffer as well, dirty bit
559 		 * needs to be preserved so that the buffer gets writeprotected
560 		 * properly on running transaction's commit.
561 		 */
562 		jh = bh2jh(bh);
563 		if (buffer_dirty(bh) ||
564 		    (jh && (jh->b_transaction != transaction ||
565 			    jh->b_next_transaction))) {
566 			folio_redirty_for_writepage(wbc, folio);
567 			goto out;
568 		}
569 	} while ((bh = bh->b_this_page) != head);
570 
571 out:
572 	return AOP_WRITEPAGE_ACTIVATE;
573 }
574 
ext4_journalled_submit_inode_data_buffers(struct jbd2_inode * jinode)575 static int ext4_journalled_submit_inode_data_buffers(struct jbd2_inode *jinode)
576 {
577 	struct address_space *mapping = jinode->i_vfs_inode->i_mapping;
578 	struct writeback_control wbc = {
579 		.sync_mode =  WB_SYNC_ALL,
580 		.nr_to_write = LONG_MAX,
581 		.range_start = jinode->i_dirty_start,
582 		.range_end = jinode->i_dirty_end,
583         };
584 
585 	return write_cache_pages(mapping, &wbc,
586 				 ext4_journalled_writepage_callback,
587 				 jinode->i_transaction);
588 }
589 
ext4_journal_submit_inode_data_buffers(struct jbd2_inode * jinode)590 static int ext4_journal_submit_inode_data_buffers(struct jbd2_inode *jinode)
591 {
592 	int ret;
593 
594 	if (ext4_should_journal_data(jinode->i_vfs_inode))
595 		ret = ext4_journalled_submit_inode_data_buffers(jinode);
596 	else
597 		ret = ext4_normal_submit_inode_data_buffers(jinode);
598 	return ret;
599 }
600 
ext4_journal_finish_inode_data_buffers(struct jbd2_inode * jinode)601 static int ext4_journal_finish_inode_data_buffers(struct jbd2_inode *jinode)
602 {
603 	int ret = 0;
604 
605 	if (!ext4_should_journal_data(jinode->i_vfs_inode))
606 		ret = jbd2_journal_finish_inode_data_buffers(jinode);
607 
608 	return ret;
609 }
610 
system_going_down(void)611 static bool system_going_down(void)
612 {
613 	return system_state == SYSTEM_HALT || system_state == SYSTEM_POWER_OFF
614 		|| system_state == SYSTEM_RESTART;
615 }
616 
617 struct ext4_err_translation {
618 	int code;
619 	int errno;
620 };
621 
622 #define EXT4_ERR_TRANSLATE(err) { .code = EXT4_ERR_##err, .errno = err }
623 
624 static struct ext4_err_translation err_translation[] = {
625 	EXT4_ERR_TRANSLATE(EIO),
626 	EXT4_ERR_TRANSLATE(ENOMEM),
627 	EXT4_ERR_TRANSLATE(EFSBADCRC),
628 	EXT4_ERR_TRANSLATE(EFSCORRUPTED),
629 	EXT4_ERR_TRANSLATE(ENOSPC),
630 	EXT4_ERR_TRANSLATE(ENOKEY),
631 	EXT4_ERR_TRANSLATE(EROFS),
632 	EXT4_ERR_TRANSLATE(EFBIG),
633 	EXT4_ERR_TRANSLATE(EEXIST),
634 	EXT4_ERR_TRANSLATE(ERANGE),
635 	EXT4_ERR_TRANSLATE(EOVERFLOW),
636 	EXT4_ERR_TRANSLATE(EBUSY),
637 	EXT4_ERR_TRANSLATE(ENOTDIR),
638 	EXT4_ERR_TRANSLATE(ENOTEMPTY),
639 	EXT4_ERR_TRANSLATE(ESHUTDOWN),
640 	EXT4_ERR_TRANSLATE(EFAULT),
641 };
642 
ext4_errno_to_code(int errno)643 static int ext4_errno_to_code(int errno)
644 {
645 	int i;
646 
647 	for (i = 0; i < ARRAY_SIZE(err_translation); i++)
648 		if (err_translation[i].errno == errno)
649 			return err_translation[i].code;
650 	return EXT4_ERR_UNKNOWN;
651 }
652 
save_error_info(struct super_block * sb,int error,__u32 ino,__u64 block,const char * func,unsigned int line)653 static void save_error_info(struct super_block *sb, int error,
654 			    __u32 ino, __u64 block,
655 			    const char *func, unsigned int line)
656 {
657 	struct ext4_sb_info *sbi = EXT4_SB(sb);
658 
659 	/* We default to EFSCORRUPTED error... */
660 	if (error == 0)
661 		error = EFSCORRUPTED;
662 
663 	spin_lock(&sbi->s_error_lock);
664 	sbi->s_add_error_count++;
665 	sbi->s_last_error_code = error;
666 	sbi->s_last_error_line = line;
667 	sbi->s_last_error_ino = ino;
668 	sbi->s_last_error_block = block;
669 	sbi->s_last_error_func = func;
670 	sbi->s_last_error_time = ktime_get_real_seconds();
671 	if (!sbi->s_first_error_time) {
672 		sbi->s_first_error_code = error;
673 		sbi->s_first_error_line = line;
674 		sbi->s_first_error_ino = ino;
675 		sbi->s_first_error_block = block;
676 		sbi->s_first_error_func = func;
677 		sbi->s_first_error_time = sbi->s_last_error_time;
678 	}
679 	spin_unlock(&sbi->s_error_lock);
680 }
681 
682 /* Deal with the reporting of failure conditions on a filesystem such as
683  * inconsistencies detected or read IO failures.
684  *
685  * On ext2, we can store the error state of the filesystem in the
686  * superblock.  That is not possible on ext4, because we may have other
687  * write ordering constraints on the superblock which prevent us from
688  * writing it out straight away; and given that the journal is about to
689  * be aborted, we can't rely on the current, or future, transactions to
690  * write out the superblock safely.
691  *
692  * We'll just use the jbd2_journal_abort() error code to record an error in
693  * the journal instead.  On recovery, the journal will complain about
694  * that error until we've noted it down and cleared it.
695  *
696  * If force_ro is set, we unconditionally force the filesystem into an
697  * ABORT|READONLY state, unless the error response on the fs has been set to
698  * panic in which case we take the easy way out and panic immediately. This is
699  * used to deal with unrecoverable failures such as journal IO errors or ENOMEM
700  * at a critical moment in log management.
701  */
ext4_handle_error(struct super_block * sb,bool force_ro,int error,__u32 ino,__u64 block,const char * func,unsigned int line)702 static void ext4_handle_error(struct super_block *sb, bool force_ro, int error,
703 			      __u32 ino, __u64 block,
704 			      const char *func, unsigned int line)
705 {
706 	journal_t *journal = EXT4_SB(sb)->s_journal;
707 	bool continue_fs = !force_ro && test_opt(sb, ERRORS_CONT);
708 
709 	EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
710 	if (test_opt(sb, WARN_ON_ERROR))
711 		WARN_ON_ONCE(1);
712 
713 	if (!continue_fs && !sb_rdonly(sb)) {
714 		set_bit(EXT4_FLAGS_SHUTDOWN, &EXT4_SB(sb)->s_ext4_flags);
715 		if (journal)
716 			jbd2_journal_abort(journal, -EIO);
717 	}
718 
719 	if (!bdev_read_only(sb->s_bdev)) {
720 		save_error_info(sb, error, ino, block, func, line);
721 		/*
722 		 * In case the fs should keep running, we need to writeout
723 		 * superblock through the journal. Due to lock ordering
724 		 * constraints, it may not be safe to do it right here so we
725 		 * defer superblock flushing to a workqueue.
726 		 */
727 		if (continue_fs && journal)
728 			schedule_work(&EXT4_SB(sb)->s_sb_upd_work);
729 		else
730 			ext4_commit_super(sb);
731 	}
732 
733 	/*
734 	 * We force ERRORS_RO behavior when system is rebooting. Otherwise we
735 	 * could panic during 'reboot -f' as the underlying device got already
736 	 * disabled.
737 	 */
738 	if (test_opt(sb, ERRORS_PANIC) && !system_going_down()) {
739 		panic("EXT4-fs (device %s): panic forced after error\n",
740 			sb->s_id);
741 	}
742 
743 	if (sb_rdonly(sb) || continue_fs)
744 		return;
745 
746 	ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
747 	/*
748 	 * Make sure updated value of ->s_mount_flags will be visible before
749 	 * ->s_flags update
750 	 */
751 	smp_wmb();
752 	sb->s_flags |= SB_RDONLY;
753 }
754 
update_super_work(struct work_struct * work)755 static void update_super_work(struct work_struct *work)
756 {
757 	struct ext4_sb_info *sbi = container_of(work, struct ext4_sb_info,
758 						s_sb_upd_work);
759 	journal_t *journal = sbi->s_journal;
760 	handle_t *handle;
761 
762 	/*
763 	 * If the journal is still running, we have to write out superblock
764 	 * through the journal to avoid collisions of other journalled sb
765 	 * updates.
766 	 *
767 	 * We use directly jbd2 functions here to avoid recursing back into
768 	 * ext4 error handling code during handling of previous errors.
769 	 */
770 	if (!sb_rdonly(sbi->s_sb) && journal) {
771 		struct buffer_head *sbh = sbi->s_sbh;
772 		bool call_notify_err = false;
773 
774 		handle = jbd2_journal_start(journal, 1);
775 		if (IS_ERR(handle))
776 			goto write_directly;
777 		if (jbd2_journal_get_write_access(handle, sbh)) {
778 			jbd2_journal_stop(handle);
779 			goto write_directly;
780 		}
781 
782 		if (sbi->s_add_error_count > 0)
783 			call_notify_err = true;
784 
785 		ext4_update_super(sbi->s_sb);
786 		if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
787 			ext4_msg(sbi->s_sb, KERN_ERR, "previous I/O error to "
788 				 "superblock detected");
789 			clear_buffer_write_io_error(sbh);
790 			set_buffer_uptodate(sbh);
791 		}
792 
793 		if (jbd2_journal_dirty_metadata(handle, sbh)) {
794 			jbd2_journal_stop(handle);
795 			goto write_directly;
796 		}
797 		jbd2_journal_stop(handle);
798 
799 		if (call_notify_err)
800 			ext4_notify_error_sysfs(sbi);
801 
802 		return;
803 	}
804 write_directly:
805 	/*
806 	 * Write through journal failed. Write sb directly to get error info
807 	 * out and hope for the best.
808 	 */
809 	ext4_commit_super(sbi->s_sb);
810 	ext4_notify_error_sysfs(sbi);
811 }
812 
813 #define ext4_error_ratelimit(sb)					\
814 		___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),	\
815 			     "EXT4-fs error")
816 
__ext4_error(struct super_block * sb,const char * function,unsigned int line,bool force_ro,int error,__u64 block,const char * fmt,...)817 void __ext4_error(struct super_block *sb, const char *function,
818 		  unsigned int line, bool force_ro, int error, __u64 block,
819 		  const char *fmt, ...)
820 {
821 	struct va_format vaf;
822 	va_list args;
823 
824 	if (unlikely(ext4_forced_shutdown(sb)))
825 		return;
826 
827 	trace_ext4_error(sb, function, line);
828 	if (ext4_error_ratelimit(sb)) {
829 		va_start(args, fmt);
830 		vaf.fmt = fmt;
831 		vaf.va = &args;
832 		printk(KERN_CRIT
833 		       "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
834 		       sb->s_id, function, line, current->comm, &vaf);
835 		va_end(args);
836 	}
837 	fsnotify_sb_error(sb, NULL, error ? error : EFSCORRUPTED);
838 
839 	ext4_handle_error(sb, force_ro, error, 0, block, function, line);
840 }
841 
__ext4_error_inode(struct inode * inode,const char * function,unsigned int line,ext4_fsblk_t block,int error,const char * fmt,...)842 void __ext4_error_inode(struct inode *inode, const char *function,
843 			unsigned int line, ext4_fsblk_t block, int error,
844 			const char *fmt, ...)
845 {
846 	va_list args;
847 	struct va_format vaf;
848 
849 	if (unlikely(ext4_forced_shutdown(inode->i_sb)))
850 		return;
851 
852 	trace_ext4_error(inode->i_sb, function, line);
853 	if (ext4_error_ratelimit(inode->i_sb)) {
854 		va_start(args, fmt);
855 		vaf.fmt = fmt;
856 		vaf.va = &args;
857 		if (block)
858 			printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
859 			       "inode #%lu: block %llu: comm %s: %pV\n",
860 			       inode->i_sb->s_id, function, line, inode->i_ino,
861 			       block, current->comm, &vaf);
862 		else
863 			printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
864 			       "inode #%lu: comm %s: %pV\n",
865 			       inode->i_sb->s_id, function, line, inode->i_ino,
866 			       current->comm, &vaf);
867 		va_end(args);
868 	}
869 	fsnotify_sb_error(inode->i_sb, inode, error ? error : EFSCORRUPTED);
870 
871 	ext4_handle_error(inode->i_sb, false, error, inode->i_ino, block,
872 			  function, line);
873 }
874 
__ext4_error_file(struct file * file,const char * function,unsigned int line,ext4_fsblk_t block,const char * fmt,...)875 void __ext4_error_file(struct file *file, const char *function,
876 		       unsigned int line, ext4_fsblk_t block,
877 		       const char *fmt, ...)
878 {
879 	va_list args;
880 	struct va_format vaf;
881 	struct inode *inode = file_inode(file);
882 	char pathname[80], *path;
883 
884 	if (unlikely(ext4_forced_shutdown(inode->i_sb)))
885 		return;
886 
887 	trace_ext4_error(inode->i_sb, function, line);
888 	if (ext4_error_ratelimit(inode->i_sb)) {
889 		path = file_path(file, pathname, sizeof(pathname));
890 		if (IS_ERR(path))
891 			path = "(unknown)";
892 		va_start(args, fmt);
893 		vaf.fmt = fmt;
894 		vaf.va = &args;
895 		if (block)
896 			printk(KERN_CRIT
897 			       "EXT4-fs error (device %s): %s:%d: inode #%lu: "
898 			       "block %llu: comm %s: path %s: %pV\n",
899 			       inode->i_sb->s_id, function, line, inode->i_ino,
900 			       block, current->comm, path, &vaf);
901 		else
902 			printk(KERN_CRIT
903 			       "EXT4-fs error (device %s): %s:%d: inode #%lu: "
904 			       "comm %s: path %s: %pV\n",
905 			       inode->i_sb->s_id, function, line, inode->i_ino,
906 			       current->comm, path, &vaf);
907 		va_end(args);
908 	}
909 	fsnotify_sb_error(inode->i_sb, inode, EFSCORRUPTED);
910 
911 	ext4_handle_error(inode->i_sb, false, EFSCORRUPTED, inode->i_ino, block,
912 			  function, line);
913 }
914 
ext4_decode_error(struct super_block * sb,int errno,char nbuf[16])915 const char *ext4_decode_error(struct super_block *sb, int errno,
916 			      char nbuf[16])
917 {
918 	char *errstr = NULL;
919 
920 	switch (errno) {
921 	case -EFSCORRUPTED:
922 		errstr = "Corrupt filesystem";
923 		break;
924 	case -EFSBADCRC:
925 		errstr = "Filesystem failed CRC";
926 		break;
927 	case -EIO:
928 		errstr = "IO failure";
929 		break;
930 	case -ENOMEM:
931 		errstr = "Out of memory";
932 		break;
933 	case -EROFS:
934 		if (!sb || (EXT4_SB(sb)->s_journal &&
935 			    EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
936 			errstr = "Journal has aborted";
937 		else
938 			errstr = "Readonly filesystem";
939 		break;
940 	default:
941 		/* If the caller passed in an extra buffer for unknown
942 		 * errors, textualise them now.  Else we just return
943 		 * NULL. */
944 		if (nbuf) {
945 			/* Check for truncated error codes... */
946 			if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
947 				errstr = nbuf;
948 		}
949 		break;
950 	}
951 
952 	return errstr;
953 }
954 
955 /* __ext4_std_error decodes expected errors from journaling functions
956  * automatically and invokes the appropriate error response.  */
957 
__ext4_std_error(struct super_block * sb,const char * function,unsigned int line,int errno)958 void __ext4_std_error(struct super_block *sb, const char *function,
959 		      unsigned int line, int errno)
960 {
961 	char nbuf[16];
962 	const char *errstr;
963 
964 	if (unlikely(ext4_forced_shutdown(sb)))
965 		return;
966 
967 	/* Special case: if the error is EROFS, and we're not already
968 	 * inside a transaction, then there's really no point in logging
969 	 * an error. */
970 	if (errno == -EROFS && journal_current_handle() == NULL && sb_rdonly(sb))
971 		return;
972 
973 	if (ext4_error_ratelimit(sb)) {
974 		errstr = ext4_decode_error(sb, errno, nbuf);
975 		printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
976 		       sb->s_id, function, line, errstr);
977 	}
978 	fsnotify_sb_error(sb, NULL, errno ? errno : EFSCORRUPTED);
979 
980 	ext4_handle_error(sb, false, -errno, 0, 0, function, line);
981 }
982 
__ext4_msg(struct super_block * sb,const char * prefix,const char * fmt,...)983 void __ext4_msg(struct super_block *sb,
984 		const char *prefix, const char *fmt, ...)
985 {
986 	struct va_format vaf;
987 	va_list args;
988 
989 	if (sb) {
990 		atomic_inc(&EXT4_SB(sb)->s_msg_count);
991 		if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state),
992 				  "EXT4-fs"))
993 			return;
994 	}
995 
996 	va_start(args, fmt);
997 	vaf.fmt = fmt;
998 	vaf.va = &args;
999 	if (sb)
1000 		printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
1001 	else
1002 		printk("%sEXT4-fs: %pV\n", prefix, &vaf);
1003 	va_end(args);
1004 }
1005 
ext4_warning_ratelimit(struct super_block * sb)1006 static int ext4_warning_ratelimit(struct super_block *sb)
1007 {
1008 	atomic_inc(&EXT4_SB(sb)->s_warning_count);
1009 	return ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state),
1010 			    "EXT4-fs warning");
1011 }
1012 
__ext4_warning(struct super_block * sb,const char * function,unsigned int line,const char * fmt,...)1013 void __ext4_warning(struct super_block *sb, const char *function,
1014 		    unsigned int line, const char *fmt, ...)
1015 {
1016 	struct va_format vaf;
1017 	va_list args;
1018 
1019 	if (!ext4_warning_ratelimit(sb))
1020 		return;
1021 
1022 	va_start(args, fmt);
1023 	vaf.fmt = fmt;
1024 	vaf.va = &args;
1025 	printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
1026 	       sb->s_id, function, line, &vaf);
1027 	va_end(args);
1028 }
1029 
__ext4_warning_inode(const struct inode * inode,const char * function,unsigned int line,const char * fmt,...)1030 void __ext4_warning_inode(const struct inode *inode, const char *function,
1031 			  unsigned int line, const char *fmt, ...)
1032 {
1033 	struct va_format vaf;
1034 	va_list args;
1035 
1036 	if (!ext4_warning_ratelimit(inode->i_sb))
1037 		return;
1038 
1039 	va_start(args, fmt);
1040 	vaf.fmt = fmt;
1041 	vaf.va = &args;
1042 	printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
1043 	       "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
1044 	       function, line, inode->i_ino, current->comm, &vaf);
1045 	va_end(args);
1046 }
1047 
__ext4_grp_locked_error(const char * function,unsigned int line,struct super_block * sb,ext4_group_t grp,unsigned long ino,ext4_fsblk_t block,const char * fmt,...)1048 void __ext4_grp_locked_error(const char *function, unsigned int line,
1049 			     struct super_block *sb, ext4_group_t grp,
1050 			     unsigned long ino, ext4_fsblk_t block,
1051 			     const char *fmt, ...)
1052 __releases(bitlock)
1053 __acquires(bitlock)
1054 {
1055 	struct va_format vaf;
1056 	va_list args;
1057 
1058 	if (unlikely(ext4_forced_shutdown(sb)))
1059 		return;
1060 
1061 	trace_ext4_error(sb, function, line);
1062 	if (ext4_error_ratelimit(sb)) {
1063 		va_start(args, fmt);
1064 		vaf.fmt = fmt;
1065 		vaf.va = &args;
1066 		printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
1067 		       sb->s_id, function, line, grp);
1068 		if (ino)
1069 			printk(KERN_CONT "inode %lu: ", ino);
1070 		if (block)
1071 			printk(KERN_CONT "block %llu:",
1072 			       (unsigned long long) block);
1073 		printk(KERN_CONT "%pV\n", &vaf);
1074 		va_end(args);
1075 	}
1076 
1077 	if (test_opt(sb, ERRORS_CONT)) {
1078 		if (test_opt(sb, WARN_ON_ERROR))
1079 			WARN_ON_ONCE(1);
1080 		EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
1081 		if (!bdev_read_only(sb->s_bdev)) {
1082 			save_error_info(sb, EFSCORRUPTED, ino, block, function,
1083 					line);
1084 			schedule_work(&EXT4_SB(sb)->s_sb_upd_work);
1085 		}
1086 		return;
1087 	}
1088 	ext4_unlock_group(sb, grp);
1089 	ext4_handle_error(sb, false, EFSCORRUPTED, ino, block, function, line);
1090 	/*
1091 	 * We only get here in the ERRORS_RO case; relocking the group
1092 	 * may be dangerous, but nothing bad will happen since the
1093 	 * filesystem will have already been marked read/only and the
1094 	 * journal has been aborted.  We return 1 as a hint to callers
1095 	 * who might what to use the return value from
1096 	 * ext4_grp_locked_error() to distinguish between the
1097 	 * ERRORS_CONT and ERRORS_RO case, and perhaps return more
1098 	 * aggressively from the ext4 function in question, with a
1099 	 * more appropriate error code.
1100 	 */
1101 	ext4_lock_group(sb, grp);
1102 	return;
1103 }
1104 
ext4_mark_group_bitmap_corrupted(struct super_block * sb,ext4_group_t group,unsigned int flags)1105 void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
1106 				     ext4_group_t group,
1107 				     unsigned int flags)
1108 {
1109 	struct ext4_sb_info *sbi = EXT4_SB(sb);
1110 	struct ext4_group_info *grp = ext4_get_group_info(sb, group);
1111 	struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
1112 	int ret;
1113 
1114 	if (!grp || !gdp)
1115 		return;
1116 	if (flags & EXT4_GROUP_INFO_BBITMAP_CORRUPT) {
1117 		ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT,
1118 					    &grp->bb_state);
1119 		if (!ret)
1120 			percpu_counter_sub(&sbi->s_freeclusters_counter,
1121 					   grp->bb_free);
1122 	}
1123 
1124 	if (flags & EXT4_GROUP_INFO_IBITMAP_CORRUPT) {
1125 		ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT,
1126 					    &grp->bb_state);
1127 		if (!ret && gdp) {
1128 			int count;
1129 
1130 			count = ext4_free_inodes_count(sb, gdp);
1131 			percpu_counter_sub(&sbi->s_freeinodes_counter,
1132 					   count);
1133 		}
1134 	}
1135 }
1136 
ext4_update_dynamic_rev(struct super_block * sb)1137 void ext4_update_dynamic_rev(struct super_block *sb)
1138 {
1139 	struct ext4_super_block *es = EXT4_SB(sb)->s_es;
1140 
1141 	if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
1142 		return;
1143 
1144 	ext4_warning(sb,
1145 		     "updating to rev %d because of new feature flag, "
1146 		     "running e2fsck is recommended",
1147 		     EXT4_DYNAMIC_REV);
1148 
1149 	es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
1150 	es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
1151 	es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
1152 	/* leave es->s_feature_*compat flags alone */
1153 	/* es->s_uuid will be set by e2fsck if empty */
1154 
1155 	/*
1156 	 * The rest of the superblock fields should be zero, and if not it
1157 	 * means they are likely already in use, so leave them alone.  We
1158 	 * can leave it up to e2fsck to clean up any inconsistencies there.
1159 	 */
1160 }
1161 
orphan_list_entry(struct list_head * l)1162 static inline struct inode *orphan_list_entry(struct list_head *l)
1163 {
1164 	return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
1165 }
1166 
dump_orphan_list(struct super_block * sb,struct ext4_sb_info * sbi)1167 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
1168 {
1169 	struct list_head *l;
1170 
1171 	ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
1172 		 le32_to_cpu(sbi->s_es->s_last_orphan));
1173 
1174 	printk(KERN_ERR "sb_info orphan list:\n");
1175 	list_for_each(l, &sbi->s_orphan) {
1176 		struct inode *inode = orphan_list_entry(l);
1177 		printk(KERN_ERR "  "
1178 		       "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
1179 		       inode->i_sb->s_id, inode->i_ino, inode,
1180 		       inode->i_mode, inode->i_nlink,
1181 		       NEXT_ORPHAN(inode));
1182 	}
1183 }
1184 
1185 #ifdef CONFIG_QUOTA
1186 static int ext4_quota_off(struct super_block *sb, int type);
1187 
ext4_quotas_off(struct super_block * sb,int type)1188 static inline void ext4_quotas_off(struct super_block *sb, int type)
1189 {
1190 	BUG_ON(type > EXT4_MAXQUOTAS);
1191 
1192 	/* Use our quota_off function to clear inode flags etc. */
1193 	for (type--; type >= 0; type--)
1194 		ext4_quota_off(sb, type);
1195 }
1196 
1197 /*
1198  * This is a helper function which is used in the mount/remount
1199  * codepaths (which holds s_umount) to fetch the quota file name.
1200  */
get_qf_name(struct super_block * sb,struct ext4_sb_info * sbi,int type)1201 static inline char *get_qf_name(struct super_block *sb,
1202 				struct ext4_sb_info *sbi,
1203 				int type)
1204 {
1205 	return rcu_dereference_protected(sbi->s_qf_names[type],
1206 					 lockdep_is_held(&sb->s_umount));
1207 }
1208 #else
ext4_quotas_off(struct super_block * sb,int type)1209 static inline void ext4_quotas_off(struct super_block *sb, int type)
1210 {
1211 }
1212 #endif
1213 
ext4_percpu_param_init(struct ext4_sb_info * sbi)1214 static int ext4_percpu_param_init(struct ext4_sb_info *sbi)
1215 {
1216 	ext4_fsblk_t block;
1217 	int err;
1218 
1219 	block = ext4_count_free_clusters(sbi->s_sb);
1220 	ext4_free_blocks_count_set(sbi->s_es, EXT4_C2B(sbi, block));
1221 	err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
1222 				  GFP_KERNEL);
1223 	if (!err) {
1224 		unsigned long freei = ext4_count_free_inodes(sbi->s_sb);
1225 		sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
1226 		err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
1227 					  GFP_KERNEL);
1228 	}
1229 	if (!err)
1230 		err = percpu_counter_init(&sbi->s_dirs_counter,
1231 					  ext4_count_dirs(sbi->s_sb), GFP_KERNEL);
1232 	if (!err)
1233 		err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
1234 					  GFP_KERNEL);
1235 	if (!err)
1236 		err = percpu_counter_init(&sbi->s_sra_exceeded_retry_limit, 0,
1237 					  GFP_KERNEL);
1238 	if (!err)
1239 		err = percpu_init_rwsem(&sbi->s_writepages_rwsem);
1240 
1241 	if (err)
1242 		ext4_msg(sbi->s_sb, KERN_ERR, "insufficient memory");
1243 
1244 	return err;
1245 }
1246 
ext4_percpu_param_destroy(struct ext4_sb_info * sbi)1247 static void ext4_percpu_param_destroy(struct ext4_sb_info *sbi)
1248 {
1249 	percpu_counter_destroy(&sbi->s_freeclusters_counter);
1250 	percpu_counter_destroy(&sbi->s_freeinodes_counter);
1251 	percpu_counter_destroy(&sbi->s_dirs_counter);
1252 	percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
1253 	percpu_counter_destroy(&sbi->s_sra_exceeded_retry_limit);
1254 	percpu_free_rwsem(&sbi->s_writepages_rwsem);
1255 }
1256 
ext4_group_desc_free(struct ext4_sb_info * sbi)1257 static void ext4_group_desc_free(struct ext4_sb_info *sbi)
1258 {
1259 	struct buffer_head **group_desc;
1260 	int i;
1261 
1262 	rcu_read_lock();
1263 	group_desc = rcu_dereference(sbi->s_group_desc);
1264 	for (i = 0; i < sbi->s_gdb_count; i++)
1265 		brelse(group_desc[i]);
1266 	kvfree(group_desc);
1267 	rcu_read_unlock();
1268 }
1269 
ext4_flex_groups_free(struct ext4_sb_info * sbi)1270 static void ext4_flex_groups_free(struct ext4_sb_info *sbi)
1271 {
1272 	struct flex_groups **flex_groups;
1273 	int i;
1274 
1275 	rcu_read_lock();
1276 	flex_groups = rcu_dereference(sbi->s_flex_groups);
1277 	if (flex_groups) {
1278 		for (i = 0; i < sbi->s_flex_groups_allocated; i++)
1279 			kvfree(flex_groups[i]);
1280 		kvfree(flex_groups);
1281 	}
1282 	rcu_read_unlock();
1283 }
1284 
ext4_put_super(struct super_block * sb)1285 static void ext4_put_super(struct super_block *sb)
1286 {
1287 	struct ext4_sb_info *sbi = EXT4_SB(sb);
1288 	struct ext4_super_block *es = sbi->s_es;
1289 	int aborted = 0;
1290 	int err;
1291 
1292 	/*
1293 	 * Unregister sysfs before destroying jbd2 journal.
1294 	 * Since we could still access attr_journal_task attribute via sysfs
1295 	 * path which could have sbi->s_journal->j_task as NULL
1296 	 * Unregister sysfs before flush sbi->s_sb_upd_work.
1297 	 * Since user may read /proc/fs/ext4/xx/mb_groups during umount, If
1298 	 * read metadata verify failed then will queue error work.
1299 	 * update_super_work will call start_this_handle may trigger
1300 	 * BUG_ON.
1301 	 */
1302 	ext4_unregister_sysfs(sb);
1303 
1304 	if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs unmount"))
1305 		ext4_msg(sb, KERN_INFO, "unmounting filesystem %pU.",
1306 			 &sb->s_uuid);
1307 
1308 	ext4_unregister_li_request(sb);
1309 	ext4_quotas_off(sb, EXT4_MAXQUOTAS);
1310 
1311 	flush_work(&sbi->s_sb_upd_work);
1312 	destroy_workqueue(sbi->rsv_conversion_wq);
1313 	ext4_release_orphan_info(sb);
1314 
1315 	if (sbi->s_journal) {
1316 		aborted = is_journal_aborted(sbi->s_journal);
1317 		err = jbd2_journal_destroy(sbi->s_journal);
1318 		sbi->s_journal = NULL;
1319 		if ((err < 0) && !aborted) {
1320 			ext4_abort(sb, -err, "Couldn't clean up the journal");
1321 		}
1322 	}
1323 
1324 	ext4_es_unregister_shrinker(sbi);
1325 	timer_shutdown_sync(&sbi->s_err_report);
1326 	ext4_release_system_zone(sb);
1327 	ext4_mb_release(sb);
1328 	ext4_ext_release(sb);
1329 
1330 	if (!sb_rdonly(sb) && !aborted) {
1331 		ext4_clear_feature_journal_needs_recovery(sb);
1332 		ext4_clear_feature_orphan_present(sb);
1333 		es->s_state = cpu_to_le16(sbi->s_mount_state);
1334 	}
1335 	if (!sb_rdonly(sb))
1336 		ext4_commit_super(sb);
1337 
1338 	ext4_group_desc_free(sbi);
1339 	ext4_flex_groups_free(sbi);
1340 	ext4_percpu_param_destroy(sbi);
1341 #ifdef CONFIG_QUOTA
1342 	for (int i = 0; i < EXT4_MAXQUOTAS; i++)
1343 		kfree(get_qf_name(sb, sbi, i));
1344 #endif
1345 
1346 	/* Debugging code just in case the in-memory inode orphan list
1347 	 * isn't empty.  The on-disk one can be non-empty if we've
1348 	 * detected an error and taken the fs readonly, but the
1349 	 * in-memory list had better be clean by this point. */
1350 	if (!list_empty(&sbi->s_orphan))
1351 		dump_orphan_list(sb, sbi);
1352 	ASSERT(list_empty(&sbi->s_orphan));
1353 
1354 	sync_blockdev(sb->s_bdev);
1355 	invalidate_bdev(sb->s_bdev);
1356 	if (sbi->s_journal_bdev) {
1357 		/*
1358 		 * Invalidate the journal device's buffers.  We don't want them
1359 		 * floating about in memory - the physical journal device may
1360 		 * hotswapped, and it breaks the `ro-after' testing code.
1361 		 */
1362 		sync_blockdev(sbi->s_journal_bdev);
1363 		invalidate_bdev(sbi->s_journal_bdev);
1364 	}
1365 
1366 	ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
1367 	sbi->s_ea_inode_cache = NULL;
1368 
1369 	ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
1370 	sbi->s_ea_block_cache = NULL;
1371 
1372 	ext4_stop_mmpd(sbi);
1373 
1374 	brelse(sbi->s_sbh);
1375 	sb->s_fs_info = NULL;
1376 	/*
1377 	 * Now that we are completely done shutting down the
1378 	 * superblock, we need to actually destroy the kobject.
1379 	 */
1380 	kobject_put(&sbi->s_kobj);
1381 	wait_for_completion(&sbi->s_kobj_unregister);
1382 	if (sbi->s_chksum_driver)
1383 		crypto_free_shash(sbi->s_chksum_driver);
1384 	kfree(sbi->s_blockgroup_lock);
1385 	fs_put_dax(sbi->s_daxdev, NULL);
1386 	fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy);
1387 #if IS_ENABLED(CONFIG_UNICODE)
1388 	utf8_unload(sb->s_encoding);
1389 #endif
1390 	kfree(sbi);
1391 }
1392 
1393 static struct kmem_cache *ext4_inode_cachep;
1394 
1395 /*
1396  * Called inside transaction, so use GFP_NOFS
1397  */
ext4_alloc_inode(struct super_block * sb)1398 static struct inode *ext4_alloc_inode(struct super_block *sb)
1399 {
1400 	struct ext4_inode_info *ei;
1401 
1402 	ei = alloc_inode_sb(sb, ext4_inode_cachep, GFP_NOFS);
1403 	if (!ei)
1404 		return NULL;
1405 
1406 	inode_set_iversion(&ei->vfs_inode, 1);
1407 	ei->i_flags = 0;
1408 	spin_lock_init(&ei->i_raw_lock);
1409 	ei->i_prealloc_node = RB_ROOT;
1410 	atomic_set(&ei->i_prealloc_active, 0);
1411 	rwlock_init(&ei->i_prealloc_lock);
1412 	ext4_es_init_tree(&ei->i_es_tree);
1413 	rwlock_init(&ei->i_es_lock);
1414 	INIT_LIST_HEAD(&ei->i_es_list);
1415 	ei->i_es_all_nr = 0;
1416 	ei->i_es_shk_nr = 0;
1417 	ei->i_es_shrink_lblk = 0;
1418 	ei->i_reserved_data_blocks = 0;
1419 	spin_lock_init(&(ei->i_block_reservation_lock));
1420 	ext4_init_pending_tree(&ei->i_pending_tree);
1421 #ifdef CONFIG_QUOTA
1422 	ei->i_reserved_quota = 0;
1423 	memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
1424 #endif
1425 	ei->jinode = NULL;
1426 	INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
1427 	spin_lock_init(&ei->i_completed_io_lock);
1428 	ei->i_sync_tid = 0;
1429 	ei->i_datasync_tid = 0;
1430 	atomic_set(&ei->i_unwritten, 0);
1431 	INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
1432 	ext4_fc_init_inode(&ei->vfs_inode);
1433 	mutex_init(&ei->i_fc_lock);
1434 	return &ei->vfs_inode;
1435 }
1436 
ext4_drop_inode(struct inode * inode)1437 static int ext4_drop_inode(struct inode *inode)
1438 {
1439 	int drop = generic_drop_inode(inode);
1440 
1441 	if (!drop)
1442 		drop = fscrypt_drop_inode(inode);
1443 
1444 	trace_ext4_drop_inode(inode, drop);
1445 	return drop;
1446 }
1447 
ext4_free_in_core_inode(struct inode * inode)1448 static void ext4_free_in_core_inode(struct inode *inode)
1449 {
1450 	fscrypt_free_inode(inode);
1451 	if (!list_empty(&(EXT4_I(inode)->i_fc_list))) {
1452 		pr_warn("%s: inode %ld still in fc list",
1453 			__func__, inode->i_ino);
1454 	}
1455 	kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1456 }
1457 
ext4_destroy_inode(struct inode * inode)1458 static void ext4_destroy_inode(struct inode *inode)
1459 {
1460 	if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1461 		ext4_msg(inode->i_sb, KERN_ERR,
1462 			 "Inode %lu (%p): orphan list check failed!",
1463 			 inode->i_ino, EXT4_I(inode));
1464 		print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1465 				EXT4_I(inode), sizeof(struct ext4_inode_info),
1466 				true);
1467 		dump_stack();
1468 	}
1469 
1470 	if (EXT4_I(inode)->i_reserved_data_blocks)
1471 		ext4_msg(inode->i_sb, KERN_ERR,
1472 			 "Inode %lu (%p): i_reserved_data_blocks (%u) not cleared!",
1473 			 inode->i_ino, EXT4_I(inode),
1474 			 EXT4_I(inode)->i_reserved_data_blocks);
1475 }
1476 
ext4_shutdown(struct super_block * sb)1477 static void ext4_shutdown(struct super_block *sb)
1478 {
1479        ext4_force_shutdown(sb, EXT4_GOING_FLAGS_NOLOGFLUSH);
1480 }
1481 
init_once(void * foo)1482 static void init_once(void *foo)
1483 {
1484 	struct ext4_inode_info *ei = foo;
1485 
1486 	INIT_LIST_HEAD(&ei->i_orphan);
1487 	init_rwsem(&ei->xattr_sem);
1488 	init_rwsem(&ei->i_data_sem);
1489 	inode_init_once(&ei->vfs_inode);
1490 	ext4_fc_init_inode(&ei->vfs_inode);
1491 }
1492 
init_inodecache(void)1493 static int __init init_inodecache(void)
1494 {
1495 	ext4_inode_cachep = kmem_cache_create_usercopy("ext4_inode_cache",
1496 				sizeof(struct ext4_inode_info), 0,
1497 				(SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
1498 					SLAB_ACCOUNT),
1499 				offsetof(struct ext4_inode_info, i_data),
1500 				sizeof_field(struct ext4_inode_info, i_data),
1501 				init_once);
1502 	if (ext4_inode_cachep == NULL)
1503 		return -ENOMEM;
1504 	return 0;
1505 }
1506 
destroy_inodecache(void)1507 static void destroy_inodecache(void)
1508 {
1509 	/*
1510 	 * Make sure all delayed rcu free inodes are flushed before we
1511 	 * destroy cache.
1512 	 */
1513 	rcu_barrier();
1514 	kmem_cache_destroy(ext4_inode_cachep);
1515 }
1516 
ext4_clear_inode(struct inode * inode)1517 void ext4_clear_inode(struct inode *inode)
1518 {
1519 	ext4_fc_del(inode);
1520 	invalidate_inode_buffers(inode);
1521 	clear_inode(inode);
1522 	ext4_discard_preallocations(inode, 0);
1523 	ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1524 	dquot_drop(inode);
1525 	if (EXT4_I(inode)->jinode) {
1526 		jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1527 					       EXT4_I(inode)->jinode);
1528 		jbd2_free_inode(EXT4_I(inode)->jinode);
1529 		EXT4_I(inode)->jinode = NULL;
1530 	}
1531 	fscrypt_put_encryption_info(inode);
1532 	fsverity_cleanup_inode(inode);
1533 }
1534 
ext4_nfs_get_inode(struct super_block * sb,u64 ino,u32 generation)1535 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1536 					u64 ino, u32 generation)
1537 {
1538 	struct inode *inode;
1539 
1540 	/*
1541 	 * Currently we don't know the generation for parent directory, so
1542 	 * a generation of 0 means "accept any"
1543 	 */
1544 	inode = ext4_iget(sb, ino, EXT4_IGET_HANDLE);
1545 	if (IS_ERR(inode))
1546 		return ERR_CAST(inode);
1547 	if (generation && inode->i_generation != generation) {
1548 		iput(inode);
1549 		return ERR_PTR(-ESTALE);
1550 	}
1551 
1552 	return inode;
1553 }
1554 
ext4_fh_to_dentry(struct super_block * sb,struct fid * fid,int fh_len,int fh_type)1555 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1556 					int fh_len, int fh_type)
1557 {
1558 	return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1559 				    ext4_nfs_get_inode);
1560 }
1561 
ext4_fh_to_parent(struct super_block * sb,struct fid * fid,int fh_len,int fh_type)1562 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1563 					int fh_len, int fh_type)
1564 {
1565 	return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1566 				    ext4_nfs_get_inode);
1567 }
1568 
ext4_nfs_commit_metadata(struct inode * inode)1569 static int ext4_nfs_commit_metadata(struct inode *inode)
1570 {
1571 	struct writeback_control wbc = {
1572 		.sync_mode = WB_SYNC_ALL
1573 	};
1574 
1575 	trace_ext4_nfs_commit_metadata(inode);
1576 	return ext4_write_inode(inode, &wbc);
1577 }
1578 
1579 #ifdef CONFIG_QUOTA
1580 static const char * const quotatypes[] = INITQFNAMES;
1581 #define QTYPE2NAME(t) (quotatypes[t])
1582 
1583 static int ext4_write_dquot(struct dquot *dquot);
1584 static int ext4_acquire_dquot(struct dquot *dquot);
1585 static int ext4_release_dquot(struct dquot *dquot);
1586 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1587 static int ext4_write_info(struct super_block *sb, int type);
1588 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1589 			 const struct path *path);
1590 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1591 			       size_t len, loff_t off);
1592 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1593 				const char *data, size_t len, loff_t off);
1594 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1595 			     unsigned int flags);
1596 
ext4_get_dquots(struct inode * inode)1597 static struct dquot __rcu **ext4_get_dquots(struct inode *inode)
1598 {
1599 	return EXT4_I(inode)->i_dquot;
1600 }
1601 
1602 static const struct dquot_operations ext4_quota_operations = {
1603 	.get_reserved_space	= ext4_get_reserved_space,
1604 	.write_dquot		= ext4_write_dquot,
1605 	.acquire_dquot		= ext4_acquire_dquot,
1606 	.release_dquot		= ext4_release_dquot,
1607 	.mark_dirty		= ext4_mark_dquot_dirty,
1608 	.write_info		= ext4_write_info,
1609 	.alloc_dquot		= dquot_alloc,
1610 	.destroy_dquot		= dquot_destroy,
1611 	.get_projid		= ext4_get_projid,
1612 	.get_inode_usage	= ext4_get_inode_usage,
1613 	.get_next_id		= dquot_get_next_id,
1614 };
1615 
1616 static const struct quotactl_ops ext4_qctl_operations = {
1617 	.quota_on	= ext4_quota_on,
1618 	.quota_off	= ext4_quota_off,
1619 	.quota_sync	= dquot_quota_sync,
1620 	.get_state	= dquot_get_state,
1621 	.set_info	= dquot_set_dqinfo,
1622 	.get_dqblk	= dquot_get_dqblk,
1623 	.set_dqblk	= dquot_set_dqblk,
1624 	.get_nextdqblk	= dquot_get_next_dqblk,
1625 };
1626 #endif
1627 
1628 static const struct super_operations ext4_sops = {
1629 	.alloc_inode	= ext4_alloc_inode,
1630 	.free_inode	= ext4_free_in_core_inode,
1631 	.destroy_inode	= ext4_destroy_inode,
1632 	.write_inode	= ext4_write_inode,
1633 	.dirty_inode	= ext4_dirty_inode,
1634 	.drop_inode	= ext4_drop_inode,
1635 	.evict_inode	= ext4_evict_inode,
1636 	.put_super	= ext4_put_super,
1637 	.sync_fs	= ext4_sync_fs,
1638 	.freeze_fs	= ext4_freeze,
1639 	.unfreeze_fs	= ext4_unfreeze,
1640 	.statfs		= ext4_statfs,
1641 	.show_options	= ext4_show_options,
1642 	.shutdown	= ext4_shutdown,
1643 #ifdef CONFIG_QUOTA
1644 	.quota_read	= ext4_quota_read,
1645 	.quota_write	= ext4_quota_write,
1646 	.get_dquots	= ext4_get_dquots,
1647 #endif
1648 };
1649 
1650 static const struct export_operations ext4_export_ops = {
1651 	.fh_to_dentry = ext4_fh_to_dentry,
1652 	.fh_to_parent = ext4_fh_to_parent,
1653 	.get_parent = ext4_get_parent,
1654 	.commit_metadata = ext4_nfs_commit_metadata,
1655 };
1656 
1657 enum {
1658 	Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1659 	Opt_resgid, Opt_resuid, Opt_sb,
1660 	Opt_nouid32, Opt_debug, Opt_removed,
1661 	Opt_user_xattr, Opt_acl,
1662 	Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1663 	Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1664 	Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1665 	Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1666 	Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1667 	Opt_inlinecrypt,
1668 	Opt_usrjquota, Opt_grpjquota, Opt_quota,
1669 	Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1670 	Opt_usrquota, Opt_grpquota, Opt_prjquota,
1671 	Opt_dax, Opt_dax_always, Opt_dax_inode, Opt_dax_never,
1672 	Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
1673 	Opt_nowarn_on_error, Opt_mblk_io_submit, Opt_debug_want_extra_isize,
1674 	Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1675 	Opt_inode_readahead_blks, Opt_journal_ioprio,
1676 	Opt_dioread_nolock, Opt_dioread_lock,
1677 	Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1678 	Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1679 	Opt_no_prefetch_block_bitmaps, Opt_mb_optimize_scan,
1680 	Opt_errors, Opt_data, Opt_data_err, Opt_jqfmt, Opt_dax_type,
1681 #ifdef CONFIG_EXT4_DEBUG
1682 	Opt_fc_debug_max_replay, Opt_fc_debug_force
1683 #endif
1684 };
1685 
1686 static const struct constant_table ext4_param_errors[] = {
1687 	{"continue",	EXT4_MOUNT_ERRORS_CONT},
1688 	{"panic",	EXT4_MOUNT_ERRORS_PANIC},
1689 	{"remount-ro",	EXT4_MOUNT_ERRORS_RO},
1690 	{}
1691 };
1692 
1693 static const struct constant_table ext4_param_data[] = {
1694 	{"journal",	EXT4_MOUNT_JOURNAL_DATA},
1695 	{"ordered",	EXT4_MOUNT_ORDERED_DATA},
1696 	{"writeback",	EXT4_MOUNT_WRITEBACK_DATA},
1697 	{}
1698 };
1699 
1700 static const struct constant_table ext4_param_data_err[] = {
1701 	{"abort",	Opt_data_err_abort},
1702 	{"ignore",	Opt_data_err_ignore},
1703 	{}
1704 };
1705 
1706 static const struct constant_table ext4_param_jqfmt[] = {
1707 	{"vfsold",	QFMT_VFS_OLD},
1708 	{"vfsv0",	QFMT_VFS_V0},
1709 	{"vfsv1",	QFMT_VFS_V1},
1710 	{}
1711 };
1712 
1713 static const struct constant_table ext4_param_dax[] = {
1714 	{"always",	Opt_dax_always},
1715 	{"inode",	Opt_dax_inode},
1716 	{"never",	Opt_dax_never},
1717 	{}
1718 };
1719 
1720 /* String parameter that allows empty argument */
1721 #define fsparam_string_empty(NAME, OPT) \
1722 	__fsparam(fs_param_is_string, NAME, OPT, fs_param_can_be_empty, NULL)
1723 
1724 /*
1725  * Mount option specification
1726  * We don't use fsparam_flag_no because of the way we set the
1727  * options and the way we show them in _ext4_show_options(). To
1728  * keep the changes to a minimum, let's keep the negative options
1729  * separate for now.
1730  */
1731 static const struct fs_parameter_spec ext4_param_specs[] = {
1732 	fsparam_flag	("bsddf",		Opt_bsd_df),
1733 	fsparam_flag	("minixdf",		Opt_minix_df),
1734 	fsparam_flag	("grpid",		Opt_grpid),
1735 	fsparam_flag	("bsdgroups",		Opt_grpid),
1736 	fsparam_flag	("nogrpid",		Opt_nogrpid),
1737 	fsparam_flag	("sysvgroups",		Opt_nogrpid),
1738 	fsparam_u32	("resgid",		Opt_resgid),
1739 	fsparam_u32	("resuid",		Opt_resuid),
1740 	fsparam_u32	("sb",			Opt_sb),
1741 	fsparam_enum	("errors",		Opt_errors, ext4_param_errors),
1742 	fsparam_flag	("nouid32",		Opt_nouid32),
1743 	fsparam_flag	("debug",		Opt_debug),
1744 	fsparam_flag	("oldalloc",		Opt_removed),
1745 	fsparam_flag	("orlov",		Opt_removed),
1746 	fsparam_flag	("user_xattr",		Opt_user_xattr),
1747 	fsparam_flag	("acl",			Opt_acl),
1748 	fsparam_flag	("norecovery",		Opt_noload),
1749 	fsparam_flag	("noload",		Opt_noload),
1750 	fsparam_flag	("bh",			Opt_removed),
1751 	fsparam_flag	("nobh",		Opt_removed),
1752 	fsparam_u32	("commit",		Opt_commit),
1753 	fsparam_u32	("min_batch_time",	Opt_min_batch_time),
1754 	fsparam_u32	("max_batch_time",	Opt_max_batch_time),
1755 	fsparam_u32	("journal_dev",		Opt_journal_dev),
1756 	fsparam_bdev	("journal_path",	Opt_journal_path),
1757 	fsparam_flag	("journal_checksum",	Opt_journal_checksum),
1758 	fsparam_flag	("nojournal_checksum",	Opt_nojournal_checksum),
1759 	fsparam_flag	("journal_async_commit",Opt_journal_async_commit),
1760 	fsparam_flag	("abort",		Opt_abort),
1761 	fsparam_enum	("data",		Opt_data, ext4_param_data),
1762 	fsparam_enum	("data_err",		Opt_data_err,
1763 						ext4_param_data_err),
1764 	fsparam_string_empty
1765 			("usrjquota",		Opt_usrjquota),
1766 	fsparam_string_empty
1767 			("grpjquota",		Opt_grpjquota),
1768 	fsparam_enum	("jqfmt",		Opt_jqfmt, ext4_param_jqfmt),
1769 	fsparam_flag	("grpquota",		Opt_grpquota),
1770 	fsparam_flag	("quota",		Opt_quota),
1771 	fsparam_flag	("noquota",		Opt_noquota),
1772 	fsparam_flag	("usrquota",		Opt_usrquota),
1773 	fsparam_flag	("prjquota",		Opt_prjquota),
1774 	fsparam_flag	("barrier",		Opt_barrier),
1775 	fsparam_u32	("barrier",		Opt_barrier),
1776 	fsparam_flag	("nobarrier",		Opt_nobarrier),
1777 	fsparam_flag	("i_version",		Opt_removed),
1778 	fsparam_flag	("dax",			Opt_dax),
1779 	fsparam_enum	("dax",			Opt_dax_type, ext4_param_dax),
1780 	fsparam_u32	("stripe",		Opt_stripe),
1781 	fsparam_flag	("delalloc",		Opt_delalloc),
1782 	fsparam_flag	("nodelalloc",		Opt_nodelalloc),
1783 	fsparam_flag	("warn_on_error",	Opt_warn_on_error),
1784 	fsparam_flag	("nowarn_on_error",	Opt_nowarn_on_error),
1785 	fsparam_u32	("debug_want_extra_isize",
1786 						Opt_debug_want_extra_isize),
1787 	fsparam_flag	("mblk_io_submit",	Opt_removed),
1788 	fsparam_flag	("nomblk_io_submit",	Opt_removed),
1789 	fsparam_flag	("block_validity",	Opt_block_validity),
1790 	fsparam_flag	("noblock_validity",	Opt_noblock_validity),
1791 	fsparam_u32	("inode_readahead_blks",
1792 						Opt_inode_readahead_blks),
1793 	fsparam_u32	("journal_ioprio",	Opt_journal_ioprio),
1794 	fsparam_u32	("auto_da_alloc",	Opt_auto_da_alloc),
1795 	fsparam_flag	("auto_da_alloc",	Opt_auto_da_alloc),
1796 	fsparam_flag	("noauto_da_alloc",	Opt_noauto_da_alloc),
1797 	fsparam_flag	("dioread_nolock",	Opt_dioread_nolock),
1798 	fsparam_flag	("nodioread_nolock",	Opt_dioread_lock),
1799 	fsparam_flag	("dioread_lock",	Opt_dioread_lock),
1800 	fsparam_flag	("discard",		Opt_discard),
1801 	fsparam_flag	("nodiscard",		Opt_nodiscard),
1802 	fsparam_u32	("init_itable",		Opt_init_itable),
1803 	fsparam_flag	("init_itable",		Opt_init_itable),
1804 	fsparam_flag	("noinit_itable",	Opt_noinit_itable),
1805 #ifdef CONFIG_EXT4_DEBUG
1806 	fsparam_flag	("fc_debug_force",	Opt_fc_debug_force),
1807 	fsparam_u32	("fc_debug_max_replay",	Opt_fc_debug_max_replay),
1808 #endif
1809 	fsparam_u32	("max_dir_size_kb",	Opt_max_dir_size_kb),
1810 	fsparam_flag	("test_dummy_encryption",
1811 						Opt_test_dummy_encryption),
1812 	fsparam_string	("test_dummy_encryption",
1813 						Opt_test_dummy_encryption),
1814 	fsparam_flag	("inlinecrypt",		Opt_inlinecrypt),
1815 	fsparam_flag	("nombcache",		Opt_nombcache),
1816 	fsparam_flag	("no_mbcache",		Opt_nombcache),	/* for backward compatibility */
1817 	fsparam_flag	("prefetch_block_bitmaps",
1818 						Opt_removed),
1819 	fsparam_flag	("no_prefetch_block_bitmaps",
1820 						Opt_no_prefetch_block_bitmaps),
1821 	fsparam_s32	("mb_optimize_scan",	Opt_mb_optimize_scan),
1822 	fsparam_string	("check",		Opt_removed),	/* mount option from ext2/3 */
1823 	fsparam_flag	("nocheck",		Opt_removed),	/* mount option from ext2/3 */
1824 	fsparam_flag	("reservation",		Opt_removed),	/* mount option from ext2/3 */
1825 	fsparam_flag	("noreservation",	Opt_removed),	/* mount option from ext2/3 */
1826 	fsparam_u32	("journal",		Opt_removed),	/* mount option from ext2/3 */
1827 	{}
1828 };
1829 
1830 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1831 
1832 #define MOPT_SET	0x0001
1833 #define MOPT_CLEAR	0x0002
1834 #define MOPT_NOSUPPORT	0x0004
1835 #define MOPT_EXPLICIT	0x0008
1836 #ifdef CONFIG_QUOTA
1837 #define MOPT_Q		0
1838 #define MOPT_QFMT	0x0010
1839 #else
1840 #define MOPT_Q		MOPT_NOSUPPORT
1841 #define MOPT_QFMT	MOPT_NOSUPPORT
1842 #endif
1843 #define MOPT_NO_EXT2	0x0020
1844 #define MOPT_NO_EXT3	0x0040
1845 #define MOPT_EXT4_ONLY	(MOPT_NO_EXT2 | MOPT_NO_EXT3)
1846 #define MOPT_SKIP	0x0080
1847 #define	MOPT_2		0x0100
1848 
1849 static const struct mount_opts {
1850 	int	token;
1851 	int	mount_opt;
1852 	int	flags;
1853 } ext4_mount_opts[] = {
1854 	{Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1855 	{Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1856 	{Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1857 	{Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1858 	{Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1859 	{Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1860 	{Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1861 	 MOPT_EXT4_ONLY | MOPT_SET},
1862 	{Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1863 	 MOPT_EXT4_ONLY | MOPT_CLEAR},
1864 	{Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1865 	{Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1866 	{Opt_delalloc, EXT4_MOUNT_DELALLOC,
1867 	 MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1868 	{Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1869 	 MOPT_EXT4_ONLY | MOPT_CLEAR},
1870 	{Opt_warn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_SET},
1871 	{Opt_nowarn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_CLEAR},
1872 	{Opt_commit, 0, MOPT_NO_EXT2},
1873 	{Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1874 	 MOPT_EXT4_ONLY | MOPT_CLEAR},
1875 	{Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1876 	 MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1877 	{Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1878 				    EXT4_MOUNT_JOURNAL_CHECKSUM),
1879 	 MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1880 	{Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1881 	{Opt_data_err, EXT4_MOUNT_DATA_ERR_ABORT, MOPT_NO_EXT2},
1882 	{Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1883 	{Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1884 	{Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1885 	{Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1886 	{Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1887 	{Opt_dax_type, 0, MOPT_EXT4_ONLY},
1888 	{Opt_journal_dev, 0, MOPT_NO_EXT2},
1889 	{Opt_journal_path, 0, MOPT_NO_EXT2},
1890 	{Opt_journal_ioprio, 0, MOPT_NO_EXT2},
1891 	{Opt_data, 0, MOPT_NO_EXT2},
1892 	{Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1893 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1894 	{Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1895 #else
1896 	{Opt_acl, 0, MOPT_NOSUPPORT},
1897 #endif
1898 	{Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1899 	{Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1900 	{Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1901 	{Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1902 							MOPT_SET | MOPT_Q},
1903 	{Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1904 							MOPT_SET | MOPT_Q},
1905 	{Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
1906 							MOPT_SET | MOPT_Q},
1907 	{Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1908 		       EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
1909 							MOPT_CLEAR | MOPT_Q},
1910 	{Opt_usrjquota, 0, MOPT_Q},
1911 	{Opt_grpjquota, 0, MOPT_Q},
1912 	{Opt_jqfmt, 0, MOPT_QFMT},
1913 	{Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
1914 	{Opt_no_prefetch_block_bitmaps, EXT4_MOUNT_NO_PREFETCH_BLOCK_BITMAPS,
1915 	 MOPT_SET},
1916 #ifdef CONFIG_EXT4_DEBUG
1917 	{Opt_fc_debug_force, EXT4_MOUNT2_JOURNAL_FAST_COMMIT,
1918 	 MOPT_SET | MOPT_2 | MOPT_EXT4_ONLY},
1919 #endif
1920 	{Opt_abort, EXT4_MOUNT2_ABORT, MOPT_SET | MOPT_2},
1921 	{Opt_err, 0, 0}
1922 };
1923 
1924 #if IS_ENABLED(CONFIG_UNICODE)
1925 static const struct ext4_sb_encodings {
1926 	__u16 magic;
1927 	char *name;
1928 	unsigned int version;
1929 } ext4_sb_encoding_map[] = {
1930 	{EXT4_ENC_UTF8_12_1, "utf8", UNICODE_AGE(12, 1, 0)},
1931 };
1932 
1933 static const struct ext4_sb_encodings *
ext4_sb_read_encoding(const struct ext4_super_block * es)1934 ext4_sb_read_encoding(const struct ext4_super_block *es)
1935 {
1936 	__u16 magic = le16_to_cpu(es->s_encoding);
1937 	int i;
1938 
1939 	for (i = 0; i < ARRAY_SIZE(ext4_sb_encoding_map); i++)
1940 		if (magic == ext4_sb_encoding_map[i].magic)
1941 			return &ext4_sb_encoding_map[i];
1942 
1943 	return NULL;
1944 }
1945 #endif
1946 
1947 #define EXT4_SPEC_JQUOTA			(1 <<  0)
1948 #define EXT4_SPEC_JQFMT				(1 <<  1)
1949 #define EXT4_SPEC_DATAJ				(1 <<  2)
1950 #define EXT4_SPEC_SB_BLOCK			(1 <<  3)
1951 #define EXT4_SPEC_JOURNAL_DEV			(1 <<  4)
1952 #define EXT4_SPEC_JOURNAL_IOPRIO		(1 <<  5)
1953 #define EXT4_SPEC_s_want_extra_isize		(1 <<  7)
1954 #define EXT4_SPEC_s_max_batch_time		(1 <<  8)
1955 #define EXT4_SPEC_s_min_batch_time		(1 <<  9)
1956 #define EXT4_SPEC_s_inode_readahead_blks	(1 << 10)
1957 #define EXT4_SPEC_s_li_wait_mult		(1 << 11)
1958 #define EXT4_SPEC_s_max_dir_size_kb		(1 << 12)
1959 #define EXT4_SPEC_s_stripe			(1 << 13)
1960 #define EXT4_SPEC_s_resuid			(1 << 14)
1961 #define EXT4_SPEC_s_resgid			(1 << 15)
1962 #define EXT4_SPEC_s_commit_interval		(1 << 16)
1963 #define EXT4_SPEC_s_fc_debug_max_replay		(1 << 17)
1964 #define EXT4_SPEC_s_sb_block			(1 << 18)
1965 #define EXT4_SPEC_mb_optimize_scan		(1 << 19)
1966 
1967 struct ext4_fs_context {
1968 	char		*s_qf_names[EXT4_MAXQUOTAS];
1969 	struct fscrypt_dummy_policy dummy_enc_policy;
1970 	int		s_jquota_fmt;	/* Format of quota to use */
1971 #ifdef CONFIG_EXT4_DEBUG
1972 	int s_fc_debug_max_replay;
1973 #endif
1974 	unsigned short	qname_spec;
1975 	unsigned long	vals_s_flags;	/* Bits to set in s_flags */
1976 	unsigned long	mask_s_flags;	/* Bits changed in s_flags */
1977 	unsigned long	journal_devnum;
1978 	unsigned long	s_commit_interval;
1979 	unsigned long	s_stripe;
1980 	unsigned int	s_inode_readahead_blks;
1981 	unsigned int	s_want_extra_isize;
1982 	unsigned int	s_li_wait_mult;
1983 	unsigned int	s_max_dir_size_kb;
1984 	unsigned int	journal_ioprio;
1985 	unsigned int	vals_s_mount_opt;
1986 	unsigned int	mask_s_mount_opt;
1987 	unsigned int	vals_s_mount_opt2;
1988 	unsigned int	mask_s_mount_opt2;
1989 	unsigned int	opt_flags;	/* MOPT flags */
1990 	unsigned int	spec;
1991 	u32		s_max_batch_time;
1992 	u32		s_min_batch_time;
1993 	kuid_t		s_resuid;
1994 	kgid_t		s_resgid;
1995 	ext4_fsblk_t	s_sb_block;
1996 };
1997 
ext4_fc_free(struct fs_context * fc)1998 static void ext4_fc_free(struct fs_context *fc)
1999 {
2000 	struct ext4_fs_context *ctx = fc->fs_private;
2001 	int i;
2002 
2003 	if (!ctx)
2004 		return;
2005 
2006 	for (i = 0; i < EXT4_MAXQUOTAS; i++)
2007 		kfree(ctx->s_qf_names[i]);
2008 
2009 	fscrypt_free_dummy_policy(&ctx->dummy_enc_policy);
2010 	kfree(ctx);
2011 }
2012 
ext4_init_fs_context(struct fs_context * fc)2013 int ext4_init_fs_context(struct fs_context *fc)
2014 {
2015 	struct ext4_fs_context *ctx;
2016 
2017 	ctx = kzalloc(sizeof(struct ext4_fs_context), GFP_KERNEL);
2018 	if (!ctx)
2019 		return -ENOMEM;
2020 
2021 	fc->fs_private = ctx;
2022 	fc->ops = &ext4_context_ops;
2023 
2024 	return 0;
2025 }
2026 
2027 #ifdef CONFIG_QUOTA
2028 /*
2029  * Note the name of the specified quota file.
2030  */
note_qf_name(struct fs_context * fc,int qtype,struct fs_parameter * param)2031 static int note_qf_name(struct fs_context *fc, int qtype,
2032 		       struct fs_parameter *param)
2033 {
2034 	struct ext4_fs_context *ctx = fc->fs_private;
2035 	char *qname;
2036 
2037 	if (param->size < 1) {
2038 		ext4_msg(NULL, KERN_ERR, "Missing quota name");
2039 		return -EINVAL;
2040 	}
2041 	if (strchr(param->string, '/')) {
2042 		ext4_msg(NULL, KERN_ERR,
2043 			 "quotafile must be on filesystem root");
2044 		return -EINVAL;
2045 	}
2046 	if (ctx->s_qf_names[qtype]) {
2047 		if (strcmp(ctx->s_qf_names[qtype], param->string) != 0) {
2048 			ext4_msg(NULL, KERN_ERR,
2049 				 "%s quota file already specified",
2050 				 QTYPE2NAME(qtype));
2051 			return -EINVAL;
2052 		}
2053 		return 0;
2054 	}
2055 
2056 	qname = kmemdup_nul(param->string, param->size, GFP_KERNEL);
2057 	if (!qname) {
2058 		ext4_msg(NULL, KERN_ERR,
2059 			 "Not enough memory for storing quotafile name");
2060 		return -ENOMEM;
2061 	}
2062 	ctx->s_qf_names[qtype] = qname;
2063 	ctx->qname_spec |= 1 << qtype;
2064 	ctx->spec |= EXT4_SPEC_JQUOTA;
2065 	return 0;
2066 }
2067 
2068 /*
2069  * Clear the name of the specified quota file.
2070  */
unnote_qf_name(struct fs_context * fc,int qtype)2071 static int unnote_qf_name(struct fs_context *fc, int qtype)
2072 {
2073 	struct ext4_fs_context *ctx = fc->fs_private;
2074 
2075 	if (ctx->s_qf_names[qtype])
2076 		kfree(ctx->s_qf_names[qtype]);
2077 
2078 	ctx->s_qf_names[qtype] = NULL;
2079 	ctx->qname_spec |= 1 << qtype;
2080 	ctx->spec |= EXT4_SPEC_JQUOTA;
2081 	return 0;
2082 }
2083 #endif
2084 
ext4_parse_test_dummy_encryption(const struct fs_parameter * param,struct ext4_fs_context * ctx)2085 static int ext4_parse_test_dummy_encryption(const struct fs_parameter *param,
2086 					    struct ext4_fs_context *ctx)
2087 {
2088 	int err;
2089 
2090 	if (!IS_ENABLED(CONFIG_FS_ENCRYPTION)) {
2091 		ext4_msg(NULL, KERN_WARNING,
2092 			 "test_dummy_encryption option not supported");
2093 		return -EINVAL;
2094 	}
2095 	err = fscrypt_parse_test_dummy_encryption(param,
2096 						  &ctx->dummy_enc_policy);
2097 	if (err == -EINVAL) {
2098 		ext4_msg(NULL, KERN_WARNING,
2099 			 "Value of option \"%s\" is unrecognized", param->key);
2100 	} else if (err == -EEXIST) {
2101 		ext4_msg(NULL, KERN_WARNING,
2102 			 "Conflicting test_dummy_encryption options");
2103 		return -EINVAL;
2104 	}
2105 	return err;
2106 }
2107 
2108 #define EXT4_SET_CTX(name)						\
2109 static inline void ctx_set_##name(struct ext4_fs_context *ctx,		\
2110 				  unsigned long flag)			\
2111 {									\
2112 	ctx->mask_s_##name |= flag;					\
2113 	ctx->vals_s_##name |= flag;					\
2114 }
2115 
2116 #define EXT4_CLEAR_CTX(name)						\
2117 static inline void ctx_clear_##name(struct ext4_fs_context *ctx,	\
2118 				    unsigned long flag)			\
2119 {									\
2120 	ctx->mask_s_##name |= flag;					\
2121 	ctx->vals_s_##name &= ~flag;					\
2122 }
2123 
2124 #define EXT4_TEST_CTX(name)						\
2125 static inline unsigned long						\
2126 ctx_test_##name(struct ext4_fs_context *ctx, unsigned long flag)	\
2127 {									\
2128 	return (ctx->vals_s_##name & flag);				\
2129 }
2130 
2131 EXT4_SET_CTX(flags); /* set only */
2132 EXT4_SET_CTX(mount_opt);
2133 EXT4_CLEAR_CTX(mount_opt);
2134 EXT4_TEST_CTX(mount_opt);
2135 EXT4_SET_CTX(mount_opt2);
2136 EXT4_CLEAR_CTX(mount_opt2);
2137 EXT4_TEST_CTX(mount_opt2);
2138 
ext4_parse_param(struct fs_context * fc,struct fs_parameter * param)2139 static int ext4_parse_param(struct fs_context *fc, struct fs_parameter *param)
2140 {
2141 	struct ext4_fs_context *ctx = fc->fs_private;
2142 	struct fs_parse_result result;
2143 	const struct mount_opts *m;
2144 	int is_remount;
2145 	kuid_t uid;
2146 	kgid_t gid;
2147 	int token;
2148 
2149 	token = fs_parse(fc, ext4_param_specs, param, &result);
2150 	if (token < 0)
2151 		return token;
2152 	is_remount = fc->purpose == FS_CONTEXT_FOR_RECONFIGURE;
2153 
2154 	for (m = ext4_mount_opts; m->token != Opt_err; m++)
2155 		if (token == m->token)
2156 			break;
2157 
2158 	ctx->opt_flags |= m->flags;
2159 
2160 	if (m->flags & MOPT_EXPLICIT) {
2161 		if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
2162 			ctx_set_mount_opt2(ctx, EXT4_MOUNT2_EXPLICIT_DELALLOC);
2163 		} else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
2164 			ctx_set_mount_opt2(ctx,
2165 				       EXT4_MOUNT2_EXPLICIT_JOURNAL_CHECKSUM);
2166 		} else
2167 			return -EINVAL;
2168 	}
2169 
2170 	if (m->flags & MOPT_NOSUPPORT) {
2171 		ext4_msg(NULL, KERN_ERR, "%s option not supported",
2172 			 param->key);
2173 		return 0;
2174 	}
2175 
2176 	switch (token) {
2177 #ifdef CONFIG_QUOTA
2178 	case Opt_usrjquota:
2179 		if (!*param->string)
2180 			return unnote_qf_name(fc, USRQUOTA);
2181 		else
2182 			return note_qf_name(fc, USRQUOTA, param);
2183 	case Opt_grpjquota:
2184 		if (!*param->string)
2185 			return unnote_qf_name(fc, GRPQUOTA);
2186 		else
2187 			return note_qf_name(fc, GRPQUOTA, param);
2188 #endif
2189 	case Opt_sb:
2190 		if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE) {
2191 			ext4_msg(NULL, KERN_WARNING,
2192 				 "Ignoring %s option on remount", param->key);
2193 		} else {
2194 			ctx->s_sb_block = result.uint_32;
2195 			ctx->spec |= EXT4_SPEC_s_sb_block;
2196 		}
2197 		return 0;
2198 	case Opt_removed:
2199 		ext4_msg(NULL, KERN_WARNING, "Ignoring removed %s option",
2200 			 param->key);
2201 		return 0;
2202 	case Opt_inlinecrypt:
2203 #ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT
2204 		ctx_set_flags(ctx, SB_INLINECRYPT);
2205 #else
2206 		ext4_msg(NULL, KERN_ERR, "inline encryption not supported");
2207 #endif
2208 		return 0;
2209 	case Opt_errors:
2210 		ctx_clear_mount_opt(ctx, EXT4_MOUNT_ERRORS_MASK);
2211 		ctx_set_mount_opt(ctx, result.uint_32);
2212 		return 0;
2213 #ifdef CONFIG_QUOTA
2214 	case Opt_jqfmt:
2215 		ctx->s_jquota_fmt = result.uint_32;
2216 		ctx->spec |= EXT4_SPEC_JQFMT;
2217 		return 0;
2218 #endif
2219 	case Opt_data:
2220 		ctx_clear_mount_opt(ctx, EXT4_MOUNT_DATA_FLAGS);
2221 		ctx_set_mount_opt(ctx, result.uint_32);
2222 		ctx->spec |= EXT4_SPEC_DATAJ;
2223 		return 0;
2224 	case Opt_commit:
2225 		if (result.uint_32 == 0)
2226 			result.uint_32 = JBD2_DEFAULT_MAX_COMMIT_AGE;
2227 		else if (result.uint_32 > INT_MAX / HZ) {
2228 			ext4_msg(NULL, KERN_ERR,
2229 				 "Invalid commit interval %d, "
2230 				 "must be smaller than %d",
2231 				 result.uint_32, INT_MAX / HZ);
2232 			return -EINVAL;
2233 		}
2234 		ctx->s_commit_interval = HZ * result.uint_32;
2235 		ctx->spec |= EXT4_SPEC_s_commit_interval;
2236 		return 0;
2237 	case Opt_debug_want_extra_isize:
2238 		if ((result.uint_32 & 1) || (result.uint_32 < 4)) {
2239 			ext4_msg(NULL, KERN_ERR,
2240 				 "Invalid want_extra_isize %d", result.uint_32);
2241 			return -EINVAL;
2242 		}
2243 		ctx->s_want_extra_isize = result.uint_32;
2244 		ctx->spec |= EXT4_SPEC_s_want_extra_isize;
2245 		return 0;
2246 	case Opt_max_batch_time:
2247 		ctx->s_max_batch_time = result.uint_32;
2248 		ctx->spec |= EXT4_SPEC_s_max_batch_time;
2249 		return 0;
2250 	case Opt_min_batch_time:
2251 		ctx->s_min_batch_time = result.uint_32;
2252 		ctx->spec |= EXT4_SPEC_s_min_batch_time;
2253 		return 0;
2254 	case Opt_inode_readahead_blks:
2255 		if (result.uint_32 &&
2256 		    (result.uint_32 > (1 << 30) ||
2257 		     !is_power_of_2(result.uint_32))) {
2258 			ext4_msg(NULL, KERN_ERR,
2259 				 "EXT4-fs: inode_readahead_blks must be "
2260 				 "0 or a power of 2 smaller than 2^31");
2261 			return -EINVAL;
2262 		}
2263 		ctx->s_inode_readahead_blks = result.uint_32;
2264 		ctx->spec |= EXT4_SPEC_s_inode_readahead_blks;
2265 		return 0;
2266 	case Opt_init_itable:
2267 		ctx_set_mount_opt(ctx, EXT4_MOUNT_INIT_INODE_TABLE);
2268 		ctx->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
2269 		if (param->type == fs_value_is_string)
2270 			ctx->s_li_wait_mult = result.uint_32;
2271 		ctx->spec |= EXT4_SPEC_s_li_wait_mult;
2272 		return 0;
2273 	case Opt_max_dir_size_kb:
2274 		ctx->s_max_dir_size_kb = result.uint_32;
2275 		ctx->spec |= EXT4_SPEC_s_max_dir_size_kb;
2276 		return 0;
2277 #ifdef CONFIG_EXT4_DEBUG
2278 	case Opt_fc_debug_max_replay:
2279 		ctx->s_fc_debug_max_replay = result.uint_32;
2280 		ctx->spec |= EXT4_SPEC_s_fc_debug_max_replay;
2281 		return 0;
2282 #endif
2283 	case Opt_stripe:
2284 		ctx->s_stripe = result.uint_32;
2285 		ctx->spec |= EXT4_SPEC_s_stripe;
2286 		return 0;
2287 	case Opt_resuid:
2288 		uid = make_kuid(current_user_ns(), result.uint_32);
2289 		if (!uid_valid(uid)) {
2290 			ext4_msg(NULL, KERN_ERR, "Invalid uid value %d",
2291 				 result.uint_32);
2292 			return -EINVAL;
2293 		}
2294 		ctx->s_resuid = uid;
2295 		ctx->spec |= EXT4_SPEC_s_resuid;
2296 		return 0;
2297 	case Opt_resgid:
2298 		gid = make_kgid(current_user_ns(), result.uint_32);
2299 		if (!gid_valid(gid)) {
2300 			ext4_msg(NULL, KERN_ERR, "Invalid gid value %d",
2301 				 result.uint_32);
2302 			return -EINVAL;
2303 		}
2304 		ctx->s_resgid = gid;
2305 		ctx->spec |= EXT4_SPEC_s_resgid;
2306 		return 0;
2307 	case Opt_journal_dev:
2308 		if (is_remount) {
2309 			ext4_msg(NULL, KERN_ERR,
2310 				 "Cannot specify journal on remount");
2311 			return -EINVAL;
2312 		}
2313 		ctx->journal_devnum = result.uint_32;
2314 		ctx->spec |= EXT4_SPEC_JOURNAL_DEV;
2315 		return 0;
2316 	case Opt_journal_path:
2317 	{
2318 		struct inode *journal_inode;
2319 		struct path path;
2320 		int error;
2321 
2322 		if (is_remount) {
2323 			ext4_msg(NULL, KERN_ERR,
2324 				 "Cannot specify journal on remount");
2325 			return -EINVAL;
2326 		}
2327 
2328 		error = fs_lookup_param(fc, param, 1, LOOKUP_FOLLOW, &path);
2329 		if (error) {
2330 			ext4_msg(NULL, KERN_ERR, "error: could not find "
2331 				 "journal device path");
2332 			return -EINVAL;
2333 		}
2334 
2335 		journal_inode = d_inode(path.dentry);
2336 		ctx->journal_devnum = new_encode_dev(journal_inode->i_rdev);
2337 		ctx->spec |= EXT4_SPEC_JOURNAL_DEV;
2338 		path_put(&path);
2339 		return 0;
2340 	}
2341 	case Opt_journal_ioprio:
2342 		if (result.uint_32 > 7) {
2343 			ext4_msg(NULL, KERN_ERR, "Invalid journal IO priority"
2344 				 " (must be 0-7)");
2345 			return -EINVAL;
2346 		}
2347 		ctx->journal_ioprio =
2348 			IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, result.uint_32);
2349 		ctx->spec |= EXT4_SPEC_JOURNAL_IOPRIO;
2350 		return 0;
2351 	case Opt_test_dummy_encryption:
2352 		return ext4_parse_test_dummy_encryption(param, ctx);
2353 	case Opt_dax:
2354 	case Opt_dax_type:
2355 #ifdef CONFIG_FS_DAX
2356 	{
2357 		int type = (token == Opt_dax) ?
2358 			   Opt_dax : result.uint_32;
2359 
2360 		switch (type) {
2361 		case Opt_dax:
2362 		case Opt_dax_always:
2363 			ctx_set_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS);
2364 			ctx_clear_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER);
2365 			break;
2366 		case Opt_dax_never:
2367 			ctx_set_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER);
2368 			ctx_clear_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS);
2369 			break;
2370 		case Opt_dax_inode:
2371 			ctx_clear_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS);
2372 			ctx_clear_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER);
2373 			/* Strictly for printing options */
2374 			ctx_set_mount_opt2(ctx, EXT4_MOUNT2_DAX_INODE);
2375 			break;
2376 		}
2377 		return 0;
2378 	}
2379 #else
2380 		ext4_msg(NULL, KERN_INFO, "dax option not supported");
2381 		return -EINVAL;
2382 #endif
2383 	case Opt_data_err:
2384 		if (result.uint_32 == Opt_data_err_abort)
2385 			ctx_set_mount_opt(ctx, m->mount_opt);
2386 		else if (result.uint_32 == Opt_data_err_ignore)
2387 			ctx_clear_mount_opt(ctx, m->mount_opt);
2388 		return 0;
2389 	case Opt_mb_optimize_scan:
2390 		if (result.int_32 == 1) {
2391 			ctx_set_mount_opt2(ctx, EXT4_MOUNT2_MB_OPTIMIZE_SCAN);
2392 			ctx->spec |= EXT4_SPEC_mb_optimize_scan;
2393 		} else if (result.int_32 == 0) {
2394 			ctx_clear_mount_opt2(ctx, EXT4_MOUNT2_MB_OPTIMIZE_SCAN);
2395 			ctx->spec |= EXT4_SPEC_mb_optimize_scan;
2396 		} else {
2397 			ext4_msg(NULL, KERN_WARNING,
2398 				 "mb_optimize_scan should be set to 0 or 1.");
2399 			return -EINVAL;
2400 		}
2401 		return 0;
2402 	}
2403 
2404 	/*
2405 	 * At this point we should only be getting options requiring MOPT_SET,
2406 	 * or MOPT_CLEAR. Anything else is a bug
2407 	 */
2408 	if (m->token == Opt_err) {
2409 		ext4_msg(NULL, KERN_WARNING, "buggy handling of option %s",
2410 			 param->key);
2411 		WARN_ON(1);
2412 		return -EINVAL;
2413 	}
2414 
2415 	else {
2416 		unsigned int set = 0;
2417 
2418 		if ((param->type == fs_value_is_flag) ||
2419 		    result.uint_32 > 0)
2420 			set = 1;
2421 
2422 		if (m->flags & MOPT_CLEAR)
2423 			set = !set;
2424 		else if (unlikely(!(m->flags & MOPT_SET))) {
2425 			ext4_msg(NULL, KERN_WARNING,
2426 				 "buggy handling of option %s",
2427 				 param->key);
2428 			WARN_ON(1);
2429 			return -EINVAL;
2430 		}
2431 		if (m->flags & MOPT_2) {
2432 			if (set != 0)
2433 				ctx_set_mount_opt2(ctx, m->mount_opt);
2434 			else
2435 				ctx_clear_mount_opt2(ctx, m->mount_opt);
2436 		} else {
2437 			if (set != 0)
2438 				ctx_set_mount_opt(ctx, m->mount_opt);
2439 			else
2440 				ctx_clear_mount_opt(ctx, m->mount_opt);
2441 		}
2442 	}
2443 
2444 	return 0;
2445 }
2446 
parse_options(struct fs_context * fc,char * options)2447 static int parse_options(struct fs_context *fc, char *options)
2448 {
2449 	struct fs_parameter param;
2450 	int ret;
2451 	char *key;
2452 
2453 	if (!options)
2454 		return 0;
2455 
2456 	while ((key = strsep(&options, ",")) != NULL) {
2457 		if (*key) {
2458 			size_t v_len = 0;
2459 			char *value = strchr(key, '=');
2460 
2461 			param.type = fs_value_is_flag;
2462 			param.string = NULL;
2463 
2464 			if (value) {
2465 				if (value == key)
2466 					continue;
2467 
2468 				*value++ = 0;
2469 				v_len = strlen(value);
2470 				param.string = kmemdup_nul(value, v_len,
2471 							   GFP_KERNEL);
2472 				if (!param.string)
2473 					return -ENOMEM;
2474 				param.type = fs_value_is_string;
2475 			}
2476 
2477 			param.key = key;
2478 			param.size = v_len;
2479 
2480 			ret = ext4_parse_param(fc, &param);
2481 			if (param.string)
2482 				kfree(param.string);
2483 			if (ret < 0)
2484 				return ret;
2485 		}
2486 	}
2487 
2488 	ret = ext4_validate_options(fc);
2489 	if (ret < 0)
2490 		return ret;
2491 
2492 	return 0;
2493 }
2494 
parse_apply_sb_mount_options(struct super_block * sb,struct ext4_fs_context * m_ctx)2495 static int parse_apply_sb_mount_options(struct super_block *sb,
2496 					struct ext4_fs_context *m_ctx)
2497 {
2498 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2499 	char *s_mount_opts = NULL;
2500 	struct ext4_fs_context *s_ctx = NULL;
2501 	struct fs_context *fc = NULL;
2502 	int ret = -ENOMEM;
2503 
2504 	if (!sbi->s_es->s_mount_opts[0])
2505 		return 0;
2506 
2507 	s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
2508 				sizeof(sbi->s_es->s_mount_opts),
2509 				GFP_KERNEL);
2510 	if (!s_mount_opts)
2511 		return ret;
2512 
2513 	fc = kzalloc(sizeof(struct fs_context), GFP_KERNEL);
2514 	if (!fc)
2515 		goto out_free;
2516 
2517 	s_ctx = kzalloc(sizeof(struct ext4_fs_context), GFP_KERNEL);
2518 	if (!s_ctx)
2519 		goto out_free;
2520 
2521 	fc->fs_private = s_ctx;
2522 	fc->s_fs_info = sbi;
2523 
2524 	ret = parse_options(fc, s_mount_opts);
2525 	if (ret < 0)
2526 		goto parse_failed;
2527 
2528 	ret = ext4_check_opt_consistency(fc, sb);
2529 	if (ret < 0) {
2530 parse_failed:
2531 		ext4_msg(sb, KERN_WARNING,
2532 			 "failed to parse options in superblock: %s",
2533 			 s_mount_opts);
2534 		ret = 0;
2535 		goto out_free;
2536 	}
2537 
2538 	if (s_ctx->spec & EXT4_SPEC_JOURNAL_DEV)
2539 		m_ctx->journal_devnum = s_ctx->journal_devnum;
2540 	if (s_ctx->spec & EXT4_SPEC_JOURNAL_IOPRIO)
2541 		m_ctx->journal_ioprio = s_ctx->journal_ioprio;
2542 
2543 	ext4_apply_options(fc, sb);
2544 	ret = 0;
2545 
2546 out_free:
2547 	if (fc) {
2548 		ext4_fc_free(fc);
2549 		kfree(fc);
2550 	}
2551 	kfree(s_mount_opts);
2552 	return ret;
2553 }
2554 
ext4_apply_quota_options(struct fs_context * fc,struct super_block * sb)2555 static void ext4_apply_quota_options(struct fs_context *fc,
2556 				     struct super_block *sb)
2557 {
2558 #ifdef CONFIG_QUOTA
2559 	bool quota_feature = ext4_has_feature_quota(sb);
2560 	struct ext4_fs_context *ctx = fc->fs_private;
2561 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2562 	char *qname;
2563 	int i;
2564 
2565 	if (quota_feature)
2566 		return;
2567 
2568 	if (ctx->spec & EXT4_SPEC_JQUOTA) {
2569 		for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2570 			if (!(ctx->qname_spec & (1 << i)))
2571 				continue;
2572 
2573 			qname = ctx->s_qf_names[i]; /* May be NULL */
2574 			if (qname)
2575 				set_opt(sb, QUOTA);
2576 			ctx->s_qf_names[i] = NULL;
2577 			qname = rcu_replace_pointer(sbi->s_qf_names[i], qname,
2578 						lockdep_is_held(&sb->s_umount));
2579 			if (qname)
2580 				kfree_rcu_mightsleep(qname);
2581 		}
2582 	}
2583 
2584 	if (ctx->spec & EXT4_SPEC_JQFMT)
2585 		sbi->s_jquota_fmt = ctx->s_jquota_fmt;
2586 #endif
2587 }
2588 
2589 /*
2590  * Check quota settings consistency.
2591  */
ext4_check_quota_consistency(struct fs_context * fc,struct super_block * sb)2592 static int ext4_check_quota_consistency(struct fs_context *fc,
2593 					struct super_block *sb)
2594 {
2595 #ifdef CONFIG_QUOTA
2596 	struct ext4_fs_context *ctx = fc->fs_private;
2597 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2598 	bool quota_feature = ext4_has_feature_quota(sb);
2599 	bool quota_loaded = sb_any_quota_loaded(sb);
2600 	bool usr_qf_name, grp_qf_name, usrquota, grpquota;
2601 	int quota_flags, i;
2602 
2603 	/*
2604 	 * We do the test below only for project quotas. 'usrquota' and
2605 	 * 'grpquota' mount options are allowed even without quota feature
2606 	 * to support legacy quotas in quota files.
2607 	 */
2608 	if (ctx_test_mount_opt(ctx, EXT4_MOUNT_PRJQUOTA) &&
2609 	    !ext4_has_feature_project(sb)) {
2610 		ext4_msg(NULL, KERN_ERR, "Project quota feature not enabled. "
2611 			 "Cannot enable project quota enforcement.");
2612 		return -EINVAL;
2613 	}
2614 
2615 	quota_flags = EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
2616 		      EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA;
2617 	if (quota_loaded &&
2618 	    ctx->mask_s_mount_opt & quota_flags &&
2619 	    !ctx_test_mount_opt(ctx, quota_flags))
2620 		goto err_quota_change;
2621 
2622 	if (ctx->spec & EXT4_SPEC_JQUOTA) {
2623 
2624 		for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2625 			if (!(ctx->qname_spec & (1 << i)))
2626 				continue;
2627 
2628 			if (quota_loaded &&
2629 			    !!sbi->s_qf_names[i] != !!ctx->s_qf_names[i])
2630 				goto err_jquota_change;
2631 
2632 			if (sbi->s_qf_names[i] && ctx->s_qf_names[i] &&
2633 			    strcmp(get_qf_name(sb, sbi, i),
2634 				   ctx->s_qf_names[i]) != 0)
2635 				goto err_jquota_specified;
2636 		}
2637 
2638 		if (quota_feature) {
2639 			ext4_msg(NULL, KERN_INFO,
2640 				 "Journaled quota options ignored when "
2641 				 "QUOTA feature is enabled");
2642 			return 0;
2643 		}
2644 	}
2645 
2646 	if (ctx->spec & EXT4_SPEC_JQFMT) {
2647 		if (sbi->s_jquota_fmt != ctx->s_jquota_fmt && quota_loaded)
2648 			goto err_jquota_change;
2649 		if (quota_feature) {
2650 			ext4_msg(NULL, KERN_INFO, "Quota format mount options "
2651 				 "ignored when QUOTA feature is enabled");
2652 			return 0;
2653 		}
2654 	}
2655 
2656 	/* Make sure we don't mix old and new quota format */
2657 	usr_qf_name = (get_qf_name(sb, sbi, USRQUOTA) ||
2658 		       ctx->s_qf_names[USRQUOTA]);
2659 	grp_qf_name = (get_qf_name(sb, sbi, GRPQUOTA) ||
2660 		       ctx->s_qf_names[GRPQUOTA]);
2661 
2662 	usrquota = (ctx_test_mount_opt(ctx, EXT4_MOUNT_USRQUOTA) ||
2663 		    test_opt(sb, USRQUOTA));
2664 
2665 	grpquota = (ctx_test_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA) ||
2666 		    test_opt(sb, GRPQUOTA));
2667 
2668 	if (usr_qf_name) {
2669 		ctx_clear_mount_opt(ctx, EXT4_MOUNT_USRQUOTA);
2670 		usrquota = false;
2671 	}
2672 	if (grp_qf_name) {
2673 		ctx_clear_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA);
2674 		grpquota = false;
2675 	}
2676 
2677 	if (usr_qf_name || grp_qf_name) {
2678 		if (usrquota || grpquota) {
2679 			ext4_msg(NULL, KERN_ERR, "old and new quota "
2680 				 "format mixing");
2681 			return -EINVAL;
2682 		}
2683 
2684 		if (!(ctx->spec & EXT4_SPEC_JQFMT || sbi->s_jquota_fmt)) {
2685 			ext4_msg(NULL, KERN_ERR, "journaled quota format "
2686 				 "not specified");
2687 			return -EINVAL;
2688 		}
2689 	}
2690 
2691 	return 0;
2692 
2693 err_quota_change:
2694 	ext4_msg(NULL, KERN_ERR,
2695 		 "Cannot change quota options when quota turned on");
2696 	return -EINVAL;
2697 err_jquota_change:
2698 	ext4_msg(NULL, KERN_ERR, "Cannot change journaled quota "
2699 		 "options when quota turned on");
2700 	return -EINVAL;
2701 err_jquota_specified:
2702 	ext4_msg(NULL, KERN_ERR, "%s quota file already specified",
2703 		 QTYPE2NAME(i));
2704 	return -EINVAL;
2705 #else
2706 	return 0;
2707 #endif
2708 }
2709 
ext4_check_test_dummy_encryption(const struct fs_context * fc,struct super_block * sb)2710 static int ext4_check_test_dummy_encryption(const struct fs_context *fc,
2711 					    struct super_block *sb)
2712 {
2713 	const struct ext4_fs_context *ctx = fc->fs_private;
2714 	const struct ext4_sb_info *sbi = EXT4_SB(sb);
2715 
2716 	if (!fscrypt_is_dummy_policy_set(&ctx->dummy_enc_policy))
2717 		return 0;
2718 
2719 	if (!ext4_has_feature_encrypt(sb)) {
2720 		ext4_msg(NULL, KERN_WARNING,
2721 			 "test_dummy_encryption requires encrypt feature");
2722 		return -EINVAL;
2723 	}
2724 	/*
2725 	 * This mount option is just for testing, and it's not worthwhile to
2726 	 * implement the extra complexity (e.g. RCU protection) that would be
2727 	 * needed to allow it to be set or changed during remount.  We do allow
2728 	 * it to be specified during remount, but only if there is no change.
2729 	 */
2730 	if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE) {
2731 		if (fscrypt_dummy_policies_equal(&sbi->s_dummy_enc_policy,
2732 						 &ctx->dummy_enc_policy))
2733 			return 0;
2734 		ext4_msg(NULL, KERN_WARNING,
2735 			 "Can't set or change test_dummy_encryption on remount");
2736 		return -EINVAL;
2737 	}
2738 	/* Also make sure s_mount_opts didn't contain a conflicting value. */
2739 	if (fscrypt_is_dummy_policy_set(&sbi->s_dummy_enc_policy)) {
2740 		if (fscrypt_dummy_policies_equal(&sbi->s_dummy_enc_policy,
2741 						 &ctx->dummy_enc_policy))
2742 			return 0;
2743 		ext4_msg(NULL, KERN_WARNING,
2744 			 "Conflicting test_dummy_encryption options");
2745 		return -EINVAL;
2746 	}
2747 	return 0;
2748 }
2749 
ext4_apply_test_dummy_encryption(struct ext4_fs_context * ctx,struct super_block * sb)2750 static void ext4_apply_test_dummy_encryption(struct ext4_fs_context *ctx,
2751 					     struct super_block *sb)
2752 {
2753 	if (!fscrypt_is_dummy_policy_set(&ctx->dummy_enc_policy) ||
2754 	    /* if already set, it was already verified to be the same */
2755 	    fscrypt_is_dummy_policy_set(&EXT4_SB(sb)->s_dummy_enc_policy))
2756 		return;
2757 	EXT4_SB(sb)->s_dummy_enc_policy = ctx->dummy_enc_policy;
2758 	memset(&ctx->dummy_enc_policy, 0, sizeof(ctx->dummy_enc_policy));
2759 	ext4_msg(sb, KERN_WARNING, "Test dummy encryption mode enabled");
2760 }
2761 
ext4_check_opt_consistency(struct fs_context * fc,struct super_block * sb)2762 static int ext4_check_opt_consistency(struct fs_context *fc,
2763 				      struct super_block *sb)
2764 {
2765 	struct ext4_fs_context *ctx = fc->fs_private;
2766 	struct ext4_sb_info *sbi = fc->s_fs_info;
2767 	int is_remount = fc->purpose == FS_CONTEXT_FOR_RECONFIGURE;
2768 	int err;
2769 
2770 	if ((ctx->opt_flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
2771 		ext4_msg(NULL, KERN_ERR,
2772 			 "Mount option(s) incompatible with ext2");
2773 		return -EINVAL;
2774 	}
2775 	if ((ctx->opt_flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
2776 		ext4_msg(NULL, KERN_ERR,
2777 			 "Mount option(s) incompatible with ext3");
2778 		return -EINVAL;
2779 	}
2780 
2781 	if (ctx->s_want_extra_isize >
2782 	    (sbi->s_inode_size - EXT4_GOOD_OLD_INODE_SIZE)) {
2783 		ext4_msg(NULL, KERN_ERR,
2784 			 "Invalid want_extra_isize %d",
2785 			 ctx->s_want_extra_isize);
2786 		return -EINVAL;
2787 	}
2788 
2789 	if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DIOREAD_NOLOCK)) {
2790 		int blocksize =
2791 			BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
2792 		if (blocksize < PAGE_SIZE)
2793 			ext4_msg(NULL, KERN_WARNING, "Warning: mounting with an "
2794 				 "experimental mount option 'dioread_nolock' "
2795 				 "for blocksize < PAGE_SIZE");
2796 	}
2797 
2798 	err = ext4_check_test_dummy_encryption(fc, sb);
2799 	if (err)
2800 		return err;
2801 
2802 	if ((ctx->spec & EXT4_SPEC_DATAJ) && is_remount) {
2803 		if (!sbi->s_journal) {
2804 			ext4_msg(NULL, KERN_WARNING,
2805 				 "Remounting file system with no journal "
2806 				 "so ignoring journalled data option");
2807 			ctx_clear_mount_opt(ctx, EXT4_MOUNT_DATA_FLAGS);
2808 		} else if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DATA_FLAGS) !=
2809 			   test_opt(sb, DATA_FLAGS)) {
2810 			ext4_msg(NULL, KERN_ERR, "Cannot change data mode "
2811 				 "on remount");
2812 			return -EINVAL;
2813 		}
2814 	}
2815 
2816 	if (is_remount) {
2817 		if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS) &&
2818 		    (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)) {
2819 			ext4_msg(NULL, KERN_ERR, "can't mount with "
2820 				 "both data=journal and dax");
2821 			return -EINVAL;
2822 		}
2823 
2824 		if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS) &&
2825 		    (!(sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2826 		     (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER))) {
2827 fail_dax_change_remount:
2828 			ext4_msg(NULL, KERN_ERR, "can't change "
2829 				 "dax mount option while remounting");
2830 			return -EINVAL;
2831 		} else if (ctx_test_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER) &&
2832 			 (!(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2833 			  (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS))) {
2834 			goto fail_dax_change_remount;
2835 		} else if (ctx_test_mount_opt2(ctx, EXT4_MOUNT2_DAX_INODE) &&
2836 			   ((sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2837 			    (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2838 			    !(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_INODE))) {
2839 			goto fail_dax_change_remount;
2840 		}
2841 	}
2842 
2843 	return ext4_check_quota_consistency(fc, sb);
2844 }
2845 
ext4_apply_options(struct fs_context * fc,struct super_block * sb)2846 static void ext4_apply_options(struct fs_context *fc, struct super_block *sb)
2847 {
2848 	struct ext4_fs_context *ctx = fc->fs_private;
2849 	struct ext4_sb_info *sbi = fc->s_fs_info;
2850 
2851 	sbi->s_mount_opt &= ~ctx->mask_s_mount_opt;
2852 	sbi->s_mount_opt |= ctx->vals_s_mount_opt;
2853 	sbi->s_mount_opt2 &= ~ctx->mask_s_mount_opt2;
2854 	sbi->s_mount_opt2 |= ctx->vals_s_mount_opt2;
2855 	sb->s_flags &= ~ctx->mask_s_flags;
2856 	sb->s_flags |= ctx->vals_s_flags;
2857 
2858 #define APPLY(X) ({ if (ctx->spec & EXT4_SPEC_##X) sbi->X = ctx->X; })
2859 	APPLY(s_commit_interval);
2860 	APPLY(s_stripe);
2861 	APPLY(s_max_batch_time);
2862 	APPLY(s_min_batch_time);
2863 	APPLY(s_want_extra_isize);
2864 	APPLY(s_inode_readahead_blks);
2865 	APPLY(s_max_dir_size_kb);
2866 	APPLY(s_li_wait_mult);
2867 	APPLY(s_resgid);
2868 	APPLY(s_resuid);
2869 
2870 #ifdef CONFIG_EXT4_DEBUG
2871 	APPLY(s_fc_debug_max_replay);
2872 #endif
2873 
2874 	ext4_apply_quota_options(fc, sb);
2875 	ext4_apply_test_dummy_encryption(ctx, sb);
2876 }
2877 
2878 
ext4_validate_options(struct fs_context * fc)2879 static int ext4_validate_options(struct fs_context *fc)
2880 {
2881 #ifdef CONFIG_QUOTA
2882 	struct ext4_fs_context *ctx = fc->fs_private;
2883 	char *usr_qf_name, *grp_qf_name;
2884 
2885 	usr_qf_name = ctx->s_qf_names[USRQUOTA];
2886 	grp_qf_name = ctx->s_qf_names[GRPQUOTA];
2887 
2888 	if (usr_qf_name || grp_qf_name) {
2889 		if (ctx_test_mount_opt(ctx, EXT4_MOUNT_USRQUOTA) && usr_qf_name)
2890 			ctx_clear_mount_opt(ctx, EXT4_MOUNT_USRQUOTA);
2891 
2892 		if (ctx_test_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA) && grp_qf_name)
2893 			ctx_clear_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA);
2894 
2895 		if (ctx_test_mount_opt(ctx, EXT4_MOUNT_USRQUOTA) ||
2896 		    ctx_test_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA)) {
2897 			ext4_msg(NULL, KERN_ERR, "old and new quota "
2898 				 "format mixing");
2899 			return -EINVAL;
2900 		}
2901 	}
2902 #endif
2903 	return 1;
2904 }
2905 
ext4_show_quota_options(struct seq_file * seq,struct super_block * sb)2906 static inline void ext4_show_quota_options(struct seq_file *seq,
2907 					   struct super_block *sb)
2908 {
2909 #if defined(CONFIG_QUOTA)
2910 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2911 	char *usr_qf_name, *grp_qf_name;
2912 
2913 	if (sbi->s_jquota_fmt) {
2914 		char *fmtname = "";
2915 
2916 		switch (sbi->s_jquota_fmt) {
2917 		case QFMT_VFS_OLD:
2918 			fmtname = "vfsold";
2919 			break;
2920 		case QFMT_VFS_V0:
2921 			fmtname = "vfsv0";
2922 			break;
2923 		case QFMT_VFS_V1:
2924 			fmtname = "vfsv1";
2925 			break;
2926 		}
2927 		seq_printf(seq, ",jqfmt=%s", fmtname);
2928 	}
2929 
2930 	rcu_read_lock();
2931 	usr_qf_name = rcu_dereference(sbi->s_qf_names[USRQUOTA]);
2932 	grp_qf_name = rcu_dereference(sbi->s_qf_names[GRPQUOTA]);
2933 	if (usr_qf_name)
2934 		seq_show_option(seq, "usrjquota", usr_qf_name);
2935 	if (grp_qf_name)
2936 		seq_show_option(seq, "grpjquota", grp_qf_name);
2937 	rcu_read_unlock();
2938 #endif
2939 }
2940 
token2str(int token)2941 static const char *token2str(int token)
2942 {
2943 	const struct fs_parameter_spec *spec;
2944 
2945 	for (spec = ext4_param_specs; spec->name != NULL; spec++)
2946 		if (spec->opt == token && !spec->type)
2947 			break;
2948 	return spec->name;
2949 }
2950 
2951 /*
2952  * Show an option if
2953  *  - it's set to a non-default value OR
2954  *  - if the per-sb default is different from the global default
2955  */
_ext4_show_options(struct seq_file * seq,struct super_block * sb,int nodefs)2956 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2957 			      int nodefs)
2958 {
2959 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2960 	struct ext4_super_block *es = sbi->s_es;
2961 	int def_errors;
2962 	const struct mount_opts *m;
2963 	char sep = nodefs ? '\n' : ',';
2964 
2965 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2966 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2967 
2968 	if (sbi->s_sb_block != 1)
2969 		SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2970 
2971 	for (m = ext4_mount_opts; m->token != Opt_err; m++) {
2972 		int want_set = m->flags & MOPT_SET;
2973 		int opt_2 = m->flags & MOPT_2;
2974 		unsigned int mount_opt, def_mount_opt;
2975 
2976 		if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
2977 		    m->flags & MOPT_SKIP)
2978 			continue;
2979 
2980 		if (opt_2) {
2981 			mount_opt = sbi->s_mount_opt2;
2982 			def_mount_opt = sbi->s_def_mount_opt2;
2983 		} else {
2984 			mount_opt = sbi->s_mount_opt;
2985 			def_mount_opt = sbi->s_def_mount_opt;
2986 		}
2987 		/* skip if same as the default */
2988 		if (!nodefs && !(m->mount_opt & (mount_opt ^ def_mount_opt)))
2989 			continue;
2990 		/* select Opt_noFoo vs Opt_Foo */
2991 		if ((want_set &&
2992 		     (mount_opt & m->mount_opt) != m->mount_opt) ||
2993 		    (!want_set && (mount_opt & m->mount_opt)))
2994 			continue;
2995 		SEQ_OPTS_PRINT("%s", token2str(m->token));
2996 	}
2997 
2998 	if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
2999 	    le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
3000 		SEQ_OPTS_PRINT("resuid=%u",
3001 				from_kuid_munged(&init_user_ns, sbi->s_resuid));
3002 	if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
3003 	    le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
3004 		SEQ_OPTS_PRINT("resgid=%u",
3005 				from_kgid_munged(&init_user_ns, sbi->s_resgid));
3006 	def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
3007 	if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
3008 		SEQ_OPTS_PUTS("errors=remount-ro");
3009 	if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
3010 		SEQ_OPTS_PUTS("errors=continue");
3011 	if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
3012 		SEQ_OPTS_PUTS("errors=panic");
3013 	if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
3014 		SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
3015 	if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
3016 		SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
3017 	if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
3018 		SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
3019 	if (nodefs || sbi->s_stripe)
3020 		SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
3021 	if (nodefs || EXT4_MOUNT_DATA_FLAGS &
3022 			(sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
3023 		if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
3024 			SEQ_OPTS_PUTS("data=journal");
3025 		else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
3026 			SEQ_OPTS_PUTS("data=ordered");
3027 		else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
3028 			SEQ_OPTS_PUTS("data=writeback");
3029 	}
3030 	if (nodefs ||
3031 	    sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
3032 		SEQ_OPTS_PRINT("inode_readahead_blks=%u",
3033 			       sbi->s_inode_readahead_blks);
3034 
3035 	if (test_opt(sb, INIT_INODE_TABLE) && (nodefs ||
3036 		       (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
3037 		SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
3038 	if (nodefs || sbi->s_max_dir_size_kb)
3039 		SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
3040 	if (test_opt(sb, DATA_ERR_ABORT))
3041 		SEQ_OPTS_PUTS("data_err=abort");
3042 
3043 	fscrypt_show_test_dummy_encryption(seq, sep, sb);
3044 
3045 	if (sb->s_flags & SB_INLINECRYPT)
3046 		SEQ_OPTS_PUTS("inlinecrypt");
3047 
3048 	if (test_opt(sb, DAX_ALWAYS)) {
3049 		if (IS_EXT2_SB(sb))
3050 			SEQ_OPTS_PUTS("dax");
3051 		else
3052 			SEQ_OPTS_PUTS("dax=always");
3053 	} else if (test_opt2(sb, DAX_NEVER)) {
3054 		SEQ_OPTS_PUTS("dax=never");
3055 	} else if (test_opt2(sb, DAX_INODE)) {
3056 		SEQ_OPTS_PUTS("dax=inode");
3057 	}
3058 
3059 	if (sbi->s_groups_count >= MB_DEFAULT_LINEAR_SCAN_THRESHOLD &&
3060 			!test_opt2(sb, MB_OPTIMIZE_SCAN)) {
3061 		SEQ_OPTS_PUTS("mb_optimize_scan=0");
3062 	} else if (sbi->s_groups_count < MB_DEFAULT_LINEAR_SCAN_THRESHOLD &&
3063 			test_opt2(sb, MB_OPTIMIZE_SCAN)) {
3064 		SEQ_OPTS_PUTS("mb_optimize_scan=1");
3065 	}
3066 
3067 	ext4_show_quota_options(seq, sb);
3068 	return 0;
3069 }
3070 
ext4_show_options(struct seq_file * seq,struct dentry * root)3071 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
3072 {
3073 	return _ext4_show_options(seq, root->d_sb, 0);
3074 }
3075 
ext4_seq_options_show(struct seq_file * seq,void * offset)3076 int ext4_seq_options_show(struct seq_file *seq, void *offset)
3077 {
3078 	struct super_block *sb = seq->private;
3079 	int rc;
3080 
3081 	seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
3082 	rc = _ext4_show_options(seq, sb, 1);
3083 	seq_puts(seq, "\n");
3084 	return rc;
3085 }
3086 
ext4_setup_super(struct super_block * sb,struct ext4_super_block * es,int read_only)3087 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
3088 			    int read_only)
3089 {
3090 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3091 	int err = 0;
3092 
3093 	if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
3094 		ext4_msg(sb, KERN_ERR, "revision level too high, "
3095 			 "forcing read-only mode");
3096 		err = -EROFS;
3097 		goto done;
3098 	}
3099 	if (read_only)
3100 		goto done;
3101 	if (!(sbi->s_mount_state & EXT4_VALID_FS))
3102 		ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
3103 			 "running e2fsck is recommended");
3104 	else if (sbi->s_mount_state & EXT4_ERROR_FS)
3105 		ext4_msg(sb, KERN_WARNING,
3106 			 "warning: mounting fs with errors, "
3107 			 "running e2fsck is recommended");
3108 	else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
3109 		 le16_to_cpu(es->s_mnt_count) >=
3110 		 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
3111 		ext4_msg(sb, KERN_WARNING,
3112 			 "warning: maximal mount count reached, "
3113 			 "running e2fsck is recommended");
3114 	else if (le32_to_cpu(es->s_checkinterval) &&
3115 		 (ext4_get_tstamp(es, s_lastcheck) +
3116 		  le32_to_cpu(es->s_checkinterval) <= ktime_get_real_seconds()))
3117 		ext4_msg(sb, KERN_WARNING,
3118 			 "warning: checktime reached, "
3119 			 "running e2fsck is recommended");
3120 	if (!sbi->s_journal)
3121 		es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
3122 	if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
3123 		es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
3124 	le16_add_cpu(&es->s_mnt_count, 1);
3125 	ext4_update_tstamp(es, s_mtime);
3126 	if (sbi->s_journal) {
3127 		ext4_set_feature_journal_needs_recovery(sb);
3128 		if (ext4_has_feature_orphan_file(sb))
3129 			ext4_set_feature_orphan_present(sb);
3130 	}
3131 
3132 	err = ext4_commit_super(sb);
3133 done:
3134 	if (test_opt(sb, DEBUG))
3135 		printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
3136 				"bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
3137 			sb->s_blocksize,
3138 			sbi->s_groups_count,
3139 			EXT4_BLOCKS_PER_GROUP(sb),
3140 			EXT4_INODES_PER_GROUP(sb),
3141 			sbi->s_mount_opt, sbi->s_mount_opt2);
3142 
3143 	cleancache_init_fs(sb);
3144 	return err;
3145 }
3146 
ext4_alloc_flex_bg_array(struct super_block * sb,ext4_group_t ngroup)3147 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
3148 {
3149 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3150 	struct flex_groups **old_groups, **new_groups;
3151 	int size, i, j;
3152 
3153 	if (!sbi->s_log_groups_per_flex)
3154 		return 0;
3155 
3156 	size = ext4_flex_group(sbi, ngroup - 1) + 1;
3157 	if (size <= sbi->s_flex_groups_allocated)
3158 		return 0;
3159 
3160 	new_groups = kvzalloc(roundup_pow_of_two(size *
3161 			      sizeof(*sbi->s_flex_groups)), GFP_KERNEL);
3162 	if (!new_groups) {
3163 		ext4_msg(sb, KERN_ERR,
3164 			 "not enough memory for %d flex group pointers", size);
3165 		return -ENOMEM;
3166 	}
3167 	for (i = sbi->s_flex_groups_allocated; i < size; i++) {
3168 		new_groups[i] = kvzalloc(roundup_pow_of_two(
3169 					 sizeof(struct flex_groups)),
3170 					 GFP_KERNEL);
3171 		if (!new_groups[i]) {
3172 			for (j = sbi->s_flex_groups_allocated; j < i; j++)
3173 				kvfree(new_groups[j]);
3174 			kvfree(new_groups);
3175 			ext4_msg(sb, KERN_ERR,
3176 				 "not enough memory for %d flex groups", size);
3177 			return -ENOMEM;
3178 		}
3179 	}
3180 	rcu_read_lock();
3181 	old_groups = rcu_dereference(sbi->s_flex_groups);
3182 	if (old_groups)
3183 		memcpy(new_groups, old_groups,
3184 		       (sbi->s_flex_groups_allocated *
3185 			sizeof(struct flex_groups *)));
3186 	rcu_read_unlock();
3187 	rcu_assign_pointer(sbi->s_flex_groups, new_groups);
3188 	sbi->s_flex_groups_allocated = size;
3189 	if (old_groups)
3190 		ext4_kvfree_array_rcu(old_groups);
3191 	return 0;
3192 }
3193 
ext4_fill_flex_info(struct super_block * sb)3194 static int ext4_fill_flex_info(struct super_block *sb)
3195 {
3196 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3197 	struct ext4_group_desc *gdp = NULL;
3198 	struct flex_groups *fg;
3199 	ext4_group_t flex_group;
3200 	int i, err;
3201 
3202 	sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
3203 	if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
3204 		sbi->s_log_groups_per_flex = 0;
3205 		return 1;
3206 	}
3207 
3208 	err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
3209 	if (err)
3210 		goto failed;
3211 
3212 	for (i = 0; i < sbi->s_groups_count; i++) {
3213 		gdp = ext4_get_group_desc(sb, i, NULL);
3214 
3215 		flex_group = ext4_flex_group(sbi, i);
3216 		fg = sbi_array_rcu_deref(sbi, s_flex_groups, flex_group);
3217 		atomic_add(ext4_free_inodes_count(sb, gdp), &fg->free_inodes);
3218 		atomic64_add(ext4_free_group_clusters(sb, gdp),
3219 			     &fg->free_clusters);
3220 		atomic_add(ext4_used_dirs_count(sb, gdp), &fg->used_dirs);
3221 	}
3222 
3223 	return 1;
3224 failed:
3225 	return 0;
3226 }
3227 
ext4_group_desc_csum(struct super_block * sb,__u32 block_group,struct ext4_group_desc * gdp)3228 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
3229 				   struct ext4_group_desc *gdp)
3230 {
3231 	int offset = offsetof(struct ext4_group_desc, bg_checksum);
3232 	__u16 crc = 0;
3233 	__le32 le_group = cpu_to_le32(block_group);
3234 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3235 
3236 	if (ext4_has_metadata_csum(sbi->s_sb)) {
3237 		/* Use new metadata_csum algorithm */
3238 		__u32 csum32;
3239 		__u16 dummy_csum = 0;
3240 
3241 		csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
3242 				     sizeof(le_group));
3243 		csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
3244 		csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
3245 				     sizeof(dummy_csum));
3246 		offset += sizeof(dummy_csum);
3247 		if (offset < sbi->s_desc_size)
3248 			csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
3249 					     sbi->s_desc_size - offset);
3250 
3251 		crc = csum32 & 0xFFFF;
3252 		goto out;
3253 	}
3254 
3255 	/* old crc16 code */
3256 	if (!ext4_has_feature_gdt_csum(sb))
3257 		return 0;
3258 
3259 	crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
3260 	crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
3261 	crc = crc16(crc, (__u8 *)gdp, offset);
3262 	offset += sizeof(gdp->bg_checksum); /* skip checksum */
3263 	/* for checksum of struct ext4_group_desc do the rest...*/
3264 	if (ext4_has_feature_64bit(sb) && offset < sbi->s_desc_size)
3265 		crc = crc16(crc, (__u8 *)gdp + offset,
3266 			    sbi->s_desc_size - offset);
3267 
3268 out:
3269 	return cpu_to_le16(crc);
3270 }
3271 
ext4_group_desc_csum_verify(struct super_block * sb,__u32 block_group,struct ext4_group_desc * gdp)3272 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
3273 				struct ext4_group_desc *gdp)
3274 {
3275 	if (ext4_has_group_desc_csum(sb) &&
3276 	    (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
3277 		return 0;
3278 
3279 	return 1;
3280 }
3281 
ext4_group_desc_csum_set(struct super_block * sb,__u32 block_group,struct ext4_group_desc * gdp)3282 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
3283 			      struct ext4_group_desc *gdp)
3284 {
3285 	if (!ext4_has_group_desc_csum(sb))
3286 		return;
3287 	gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
3288 }
3289 
3290 /* Called at mount-time, super-block is locked */
ext4_check_descriptors(struct super_block * sb,ext4_fsblk_t sb_block,ext4_group_t * first_not_zeroed)3291 static int ext4_check_descriptors(struct super_block *sb,
3292 				  ext4_fsblk_t sb_block,
3293 				  ext4_group_t *first_not_zeroed)
3294 {
3295 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3296 	ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
3297 	ext4_fsblk_t last_block;
3298 	ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0);
3299 	ext4_fsblk_t block_bitmap;
3300 	ext4_fsblk_t inode_bitmap;
3301 	ext4_fsblk_t inode_table;
3302 	int flexbg_flag = 0;
3303 	ext4_group_t i, grp = sbi->s_groups_count;
3304 
3305 	if (ext4_has_feature_flex_bg(sb))
3306 		flexbg_flag = 1;
3307 
3308 	ext4_debug("Checking group descriptors");
3309 
3310 	for (i = 0; i < sbi->s_groups_count; i++) {
3311 		struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
3312 
3313 		if (i == sbi->s_groups_count - 1 || flexbg_flag)
3314 			last_block = ext4_blocks_count(sbi->s_es) - 1;
3315 		else
3316 			last_block = first_block +
3317 				(EXT4_BLOCKS_PER_GROUP(sb) - 1);
3318 
3319 		if ((grp == sbi->s_groups_count) &&
3320 		   !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3321 			grp = i;
3322 
3323 		block_bitmap = ext4_block_bitmap(sb, gdp);
3324 		if (block_bitmap == sb_block) {
3325 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3326 				 "Block bitmap for group %u overlaps "
3327 				 "superblock", i);
3328 			if (!sb_rdonly(sb))
3329 				return 0;
3330 		}
3331 		if (block_bitmap >= sb_block + 1 &&
3332 		    block_bitmap <= last_bg_block) {
3333 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3334 				 "Block bitmap for group %u overlaps "
3335 				 "block group descriptors", i);
3336 			if (!sb_rdonly(sb))
3337 				return 0;
3338 		}
3339 		if (block_bitmap < first_block || block_bitmap > last_block) {
3340 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3341 			       "Block bitmap for group %u not in group "
3342 			       "(block %llu)!", i, block_bitmap);
3343 			return 0;
3344 		}
3345 		inode_bitmap = ext4_inode_bitmap(sb, gdp);
3346 		if (inode_bitmap == sb_block) {
3347 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3348 				 "Inode bitmap for group %u overlaps "
3349 				 "superblock", i);
3350 			if (!sb_rdonly(sb))
3351 				return 0;
3352 		}
3353 		if (inode_bitmap >= sb_block + 1 &&
3354 		    inode_bitmap <= last_bg_block) {
3355 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3356 				 "Inode bitmap for group %u overlaps "
3357 				 "block group descriptors", i);
3358 			if (!sb_rdonly(sb))
3359 				return 0;
3360 		}
3361 		if (inode_bitmap < first_block || inode_bitmap > last_block) {
3362 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3363 			       "Inode bitmap for group %u not in group "
3364 			       "(block %llu)!", i, inode_bitmap);
3365 			return 0;
3366 		}
3367 		inode_table = ext4_inode_table(sb, gdp);
3368 		if (inode_table == sb_block) {
3369 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3370 				 "Inode table for group %u overlaps "
3371 				 "superblock", i);
3372 			if (!sb_rdonly(sb))
3373 				return 0;
3374 		}
3375 		if (inode_table >= sb_block + 1 &&
3376 		    inode_table <= last_bg_block) {
3377 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3378 				 "Inode table for group %u overlaps "
3379 				 "block group descriptors", i);
3380 			if (!sb_rdonly(sb))
3381 				return 0;
3382 		}
3383 		if (inode_table < first_block ||
3384 		    inode_table + sbi->s_itb_per_group - 1 > last_block) {
3385 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3386 			       "Inode table for group %u not in group "
3387 			       "(block %llu)!", i, inode_table);
3388 			return 0;
3389 		}
3390 		ext4_lock_group(sb, i);
3391 		if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
3392 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3393 				 "Checksum for group %u failed (%u!=%u)",
3394 				 i, le16_to_cpu(ext4_group_desc_csum(sb, i,
3395 				     gdp)), le16_to_cpu(gdp->bg_checksum));
3396 			if (!sb_rdonly(sb)) {
3397 				ext4_unlock_group(sb, i);
3398 				return 0;
3399 			}
3400 		}
3401 		ext4_unlock_group(sb, i);
3402 		if (!flexbg_flag)
3403 			first_block += EXT4_BLOCKS_PER_GROUP(sb);
3404 	}
3405 	if (NULL != first_not_zeroed)
3406 		*first_not_zeroed = grp;
3407 	return 1;
3408 }
3409 
3410 /*
3411  * Maximal extent format file size.
3412  * Resulting logical blkno at s_maxbytes must fit in our on-disk
3413  * extent format containers, within a sector_t, and within i_blocks
3414  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
3415  * so that won't be a limiting factor.
3416  *
3417  * However there is other limiting factor. We do store extents in the form
3418  * of starting block and length, hence the resulting length of the extent
3419  * covering maximum file size must fit into on-disk format containers as
3420  * well. Given that length is always by 1 unit bigger than max unit (because
3421  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
3422  *
3423  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
3424  */
ext4_max_size(int blkbits,int has_huge_files)3425 static loff_t ext4_max_size(int blkbits, int has_huge_files)
3426 {
3427 	loff_t res;
3428 	loff_t upper_limit = MAX_LFS_FILESIZE;
3429 
3430 	BUILD_BUG_ON(sizeof(blkcnt_t) < sizeof(u64));
3431 
3432 	if (!has_huge_files) {
3433 		upper_limit = (1LL << 32) - 1;
3434 
3435 		/* total blocks in file system block size */
3436 		upper_limit >>= (blkbits - 9);
3437 		upper_limit <<= blkbits;
3438 	}
3439 
3440 	/*
3441 	 * 32-bit extent-start container, ee_block. We lower the maxbytes
3442 	 * by one fs block, so ee_len can cover the extent of maximum file
3443 	 * size
3444 	 */
3445 	res = (1LL << 32) - 1;
3446 	res <<= blkbits;
3447 
3448 	/* Sanity check against vm- & vfs- imposed limits */
3449 	if (res > upper_limit)
3450 		res = upper_limit;
3451 
3452 	return res;
3453 }
3454 
3455 /*
3456  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
3457  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
3458  * We need to be 1 filesystem block less than the 2^48 sector limit.
3459  */
ext4_max_bitmap_size(int bits,int has_huge_files)3460 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
3461 {
3462 	loff_t upper_limit, res = EXT4_NDIR_BLOCKS;
3463 	int meta_blocks;
3464 	unsigned int ppb = 1 << (bits - 2);
3465 
3466 	/*
3467 	 * This is calculated to be the largest file size for a dense, block
3468 	 * mapped file such that the file's total number of 512-byte sectors,
3469 	 * including data and all indirect blocks, does not exceed (2^48 - 1).
3470 	 *
3471 	 * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
3472 	 * number of 512-byte sectors of the file.
3473 	 */
3474 	if (!has_huge_files) {
3475 		/*
3476 		 * !has_huge_files or implies that the inode i_block field
3477 		 * represents total file blocks in 2^32 512-byte sectors ==
3478 		 * size of vfs inode i_blocks * 8
3479 		 */
3480 		upper_limit = (1LL << 32) - 1;
3481 
3482 		/* total blocks in file system block size */
3483 		upper_limit >>= (bits - 9);
3484 
3485 	} else {
3486 		/*
3487 		 * We use 48 bit ext4_inode i_blocks
3488 		 * With EXT4_HUGE_FILE_FL set the i_blocks
3489 		 * represent total number of blocks in
3490 		 * file system block size
3491 		 */
3492 		upper_limit = (1LL << 48) - 1;
3493 
3494 	}
3495 
3496 	/* Compute how many blocks we can address by block tree */
3497 	res += ppb;
3498 	res += ppb * ppb;
3499 	res += ((loff_t)ppb) * ppb * ppb;
3500 	/* Compute how many metadata blocks are needed */
3501 	meta_blocks = 1;
3502 	meta_blocks += 1 + ppb;
3503 	meta_blocks += 1 + ppb + ppb * ppb;
3504 	/* Does block tree limit file size? */
3505 	if (res + meta_blocks <= upper_limit)
3506 		goto check_lfs;
3507 
3508 	res = upper_limit;
3509 	/* How many metadata blocks are needed for addressing upper_limit? */
3510 	upper_limit -= EXT4_NDIR_BLOCKS;
3511 	/* indirect blocks */
3512 	meta_blocks = 1;
3513 	upper_limit -= ppb;
3514 	/* double indirect blocks */
3515 	if (upper_limit < ppb * ppb) {
3516 		meta_blocks += 1 + DIV_ROUND_UP_ULL(upper_limit, ppb);
3517 		res -= meta_blocks;
3518 		goto check_lfs;
3519 	}
3520 	meta_blocks += 1 + ppb;
3521 	upper_limit -= ppb * ppb;
3522 	/* tripple indirect blocks for the rest */
3523 	meta_blocks += 1 + DIV_ROUND_UP_ULL(upper_limit, ppb) +
3524 		DIV_ROUND_UP_ULL(upper_limit, ppb*ppb);
3525 	res -= meta_blocks;
3526 check_lfs:
3527 	res <<= bits;
3528 	if (res > MAX_LFS_FILESIZE)
3529 		res = MAX_LFS_FILESIZE;
3530 
3531 	return res;
3532 }
3533 
descriptor_loc(struct super_block * sb,ext4_fsblk_t logical_sb_block,int nr)3534 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
3535 				   ext4_fsblk_t logical_sb_block, int nr)
3536 {
3537 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3538 	ext4_group_t bg, first_meta_bg;
3539 	int has_super = 0;
3540 
3541 	first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
3542 
3543 	if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
3544 		return logical_sb_block + nr + 1;
3545 	bg = sbi->s_desc_per_block * nr;
3546 	if (ext4_bg_has_super(sb, bg))
3547 		has_super = 1;
3548 
3549 	/*
3550 	 * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
3551 	 * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
3552 	 * on modern mke2fs or blksize > 1k on older mke2fs) then we must
3553 	 * compensate.
3554 	 */
3555 	if (sb->s_blocksize == 1024 && nr == 0 &&
3556 	    le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
3557 		has_super++;
3558 
3559 	return (has_super + ext4_group_first_block_no(sb, bg));
3560 }
3561 
3562 /**
3563  * ext4_get_stripe_size: Get the stripe size.
3564  * @sbi: In memory super block info
3565  *
3566  * If we have specified it via mount option, then
3567  * use the mount option value. If the value specified at mount time is
3568  * greater than the blocks per group use the super block value.
3569  * If the super block value is greater than blocks per group return 0.
3570  * Allocator needs it be less than blocks per group.
3571  *
3572  */
ext4_get_stripe_size(struct ext4_sb_info * sbi)3573 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
3574 {
3575 	unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
3576 	unsigned long stripe_width =
3577 			le32_to_cpu(sbi->s_es->s_raid_stripe_width);
3578 	int ret;
3579 
3580 	if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
3581 		ret = sbi->s_stripe;
3582 	else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
3583 		ret = stripe_width;
3584 	else if (stride && stride <= sbi->s_blocks_per_group)
3585 		ret = stride;
3586 	else
3587 		ret = 0;
3588 
3589 	/*
3590 	 * If the stripe width is 1, this makes no sense and
3591 	 * we set it to 0 to turn off stripe handling code.
3592 	 */
3593 	if (ret <= 1)
3594 		ret = 0;
3595 
3596 	return ret;
3597 }
3598 
3599 /*
3600  * Check whether this filesystem can be mounted based on
3601  * the features present and the RDONLY/RDWR mount requested.
3602  * Returns 1 if this filesystem can be mounted as requested,
3603  * 0 if it cannot be.
3604  */
ext4_feature_set_ok(struct super_block * sb,int readonly)3605 int ext4_feature_set_ok(struct super_block *sb, int readonly)
3606 {
3607 	if (ext4_has_unknown_ext4_incompat_features(sb)) {
3608 		ext4_msg(sb, KERN_ERR,
3609 			"Couldn't mount because of "
3610 			"unsupported optional features (%x)",
3611 			(le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
3612 			~EXT4_FEATURE_INCOMPAT_SUPP));
3613 		return 0;
3614 	}
3615 
3616 #if !IS_ENABLED(CONFIG_UNICODE)
3617 	if (ext4_has_feature_casefold(sb)) {
3618 		ext4_msg(sb, KERN_ERR,
3619 			 "Filesystem with casefold feature cannot be "
3620 			 "mounted without CONFIG_UNICODE");
3621 		return 0;
3622 	}
3623 #endif
3624 
3625 	if (readonly)
3626 		return 1;
3627 
3628 	if (ext4_has_feature_readonly(sb)) {
3629 		ext4_msg(sb, KERN_INFO, "filesystem is read-only");
3630 		sb->s_flags |= SB_RDONLY;
3631 		return 1;
3632 	}
3633 
3634 	/* Check that feature set is OK for a read-write mount */
3635 	if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
3636 		ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
3637 			 "unsupported optional features (%x)",
3638 			 (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
3639 				~EXT4_FEATURE_RO_COMPAT_SUPP));
3640 		return 0;
3641 	}
3642 	if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
3643 		ext4_msg(sb, KERN_ERR,
3644 			 "Can't support bigalloc feature without "
3645 			 "extents feature\n");
3646 		return 0;
3647 	}
3648 
3649 #if !IS_ENABLED(CONFIG_QUOTA) || !IS_ENABLED(CONFIG_QFMT_V2)
3650 	if (!readonly && (ext4_has_feature_quota(sb) ||
3651 			  ext4_has_feature_project(sb))) {
3652 		ext4_msg(sb, KERN_ERR,
3653 			 "The kernel was not built with CONFIG_QUOTA and CONFIG_QFMT_V2");
3654 		return 0;
3655 	}
3656 #endif  /* CONFIG_QUOTA */
3657 	return 1;
3658 }
3659 
3660 /*
3661  * This function is called once a day if we have errors logged
3662  * on the file system
3663  */
print_daily_error_info(struct timer_list * t)3664 static void print_daily_error_info(struct timer_list *t)
3665 {
3666 	struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
3667 	struct super_block *sb = sbi->s_sb;
3668 	struct ext4_super_block *es = sbi->s_es;
3669 
3670 	if (es->s_error_count)
3671 		/* fsck newer than v1.41.13 is needed to clean this condition. */
3672 		ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
3673 			 le32_to_cpu(es->s_error_count));
3674 	if (es->s_first_error_time) {
3675 		printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %llu: %.*s:%d",
3676 		       sb->s_id,
3677 		       ext4_get_tstamp(es, s_first_error_time),
3678 		       (int) sizeof(es->s_first_error_func),
3679 		       es->s_first_error_func,
3680 		       le32_to_cpu(es->s_first_error_line));
3681 		if (es->s_first_error_ino)
3682 			printk(KERN_CONT ": inode %u",
3683 			       le32_to_cpu(es->s_first_error_ino));
3684 		if (es->s_first_error_block)
3685 			printk(KERN_CONT ": block %llu", (unsigned long long)
3686 			       le64_to_cpu(es->s_first_error_block));
3687 		printk(KERN_CONT "\n");
3688 	}
3689 	if (es->s_last_error_time) {
3690 		printk(KERN_NOTICE "EXT4-fs (%s): last error at time %llu: %.*s:%d",
3691 		       sb->s_id,
3692 		       ext4_get_tstamp(es, s_last_error_time),
3693 		       (int) sizeof(es->s_last_error_func),
3694 		       es->s_last_error_func,
3695 		       le32_to_cpu(es->s_last_error_line));
3696 		if (es->s_last_error_ino)
3697 			printk(KERN_CONT ": inode %u",
3698 			       le32_to_cpu(es->s_last_error_ino));
3699 		if (es->s_last_error_block)
3700 			printk(KERN_CONT ": block %llu", (unsigned long long)
3701 			       le64_to_cpu(es->s_last_error_block));
3702 		printk(KERN_CONT "\n");
3703 	}
3704 	mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
3705 }
3706 
3707 /* Find next suitable group and run ext4_init_inode_table */
ext4_run_li_request(struct ext4_li_request * elr)3708 static int ext4_run_li_request(struct ext4_li_request *elr)
3709 {
3710 	struct ext4_group_desc *gdp = NULL;
3711 	struct super_block *sb = elr->lr_super;
3712 	ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
3713 	ext4_group_t group = elr->lr_next_group;
3714 	unsigned int prefetch_ios = 0;
3715 	int ret = 0;
3716 	int nr = EXT4_SB(sb)->s_mb_prefetch;
3717 	u64 start_time;
3718 
3719 	if (elr->lr_mode == EXT4_LI_MODE_PREFETCH_BBITMAP) {
3720 		elr->lr_next_group = ext4_mb_prefetch(sb, group, nr, &prefetch_ios);
3721 		ext4_mb_prefetch_fini(sb, elr->lr_next_group, nr);
3722 		trace_ext4_prefetch_bitmaps(sb, group, elr->lr_next_group, nr);
3723 		if (group >= elr->lr_next_group) {
3724 			ret = 1;
3725 			if (elr->lr_first_not_zeroed != ngroups &&
3726 			    !sb_rdonly(sb) && test_opt(sb, INIT_INODE_TABLE)) {
3727 				elr->lr_next_group = elr->lr_first_not_zeroed;
3728 				elr->lr_mode = EXT4_LI_MODE_ITABLE;
3729 				ret = 0;
3730 			}
3731 		}
3732 		return ret;
3733 	}
3734 
3735 	for (; group < ngroups; group++) {
3736 		gdp = ext4_get_group_desc(sb, group, NULL);
3737 		if (!gdp) {
3738 			ret = 1;
3739 			break;
3740 		}
3741 
3742 		if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3743 			break;
3744 	}
3745 
3746 	if (group >= ngroups)
3747 		ret = 1;
3748 
3749 	if (!ret) {
3750 		start_time = ktime_get_real_ns();
3751 		ret = ext4_init_inode_table(sb, group,
3752 					    elr->lr_timeout ? 0 : 1);
3753 		trace_ext4_lazy_itable_init(sb, group);
3754 		if (elr->lr_timeout == 0) {
3755 			elr->lr_timeout = nsecs_to_jiffies((ktime_get_real_ns() - start_time) *
3756 				EXT4_SB(elr->lr_super)->s_li_wait_mult);
3757 		}
3758 		elr->lr_next_sched = jiffies + elr->lr_timeout;
3759 		elr->lr_next_group = group + 1;
3760 	}
3761 	return ret;
3762 }
3763 
3764 /*
3765  * Remove lr_request from the list_request and free the
3766  * request structure. Should be called with li_list_mtx held
3767  */
ext4_remove_li_request(struct ext4_li_request * elr)3768 static void ext4_remove_li_request(struct ext4_li_request *elr)
3769 {
3770 	if (!elr)
3771 		return;
3772 
3773 	list_del(&elr->lr_request);
3774 	EXT4_SB(elr->lr_super)->s_li_request = NULL;
3775 	kfree(elr);
3776 }
3777 
ext4_unregister_li_request(struct super_block * sb)3778 static void ext4_unregister_li_request(struct super_block *sb)
3779 {
3780 	mutex_lock(&ext4_li_mtx);
3781 	if (!ext4_li_info) {
3782 		mutex_unlock(&ext4_li_mtx);
3783 		return;
3784 	}
3785 
3786 	mutex_lock(&ext4_li_info->li_list_mtx);
3787 	ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
3788 	mutex_unlock(&ext4_li_info->li_list_mtx);
3789 	mutex_unlock(&ext4_li_mtx);
3790 }
3791 
3792 static struct task_struct *ext4_lazyinit_task;
3793 
3794 /*
3795  * This is the function where ext4lazyinit thread lives. It walks
3796  * through the request list searching for next scheduled filesystem.
3797  * When such a fs is found, run the lazy initialization request
3798  * (ext4_rn_li_request) and keep track of the time spend in this
3799  * function. Based on that time we compute next schedule time of
3800  * the request. When walking through the list is complete, compute
3801  * next waking time and put itself into sleep.
3802  */
ext4_lazyinit_thread(void * arg)3803 static int ext4_lazyinit_thread(void *arg)
3804 {
3805 	struct ext4_lazy_init *eli = arg;
3806 	struct list_head *pos, *n;
3807 	struct ext4_li_request *elr;
3808 	unsigned long next_wakeup, cur;
3809 
3810 	BUG_ON(NULL == eli);
3811 	set_freezable();
3812 
3813 cont_thread:
3814 	while (true) {
3815 		next_wakeup = MAX_JIFFY_OFFSET;
3816 
3817 		mutex_lock(&eli->li_list_mtx);
3818 		if (list_empty(&eli->li_request_list)) {
3819 			mutex_unlock(&eli->li_list_mtx);
3820 			goto exit_thread;
3821 		}
3822 		list_for_each_safe(pos, n, &eli->li_request_list) {
3823 			int err = 0;
3824 			int progress = 0;
3825 			elr = list_entry(pos, struct ext4_li_request,
3826 					 lr_request);
3827 
3828 			if (time_before(jiffies, elr->lr_next_sched)) {
3829 				if (time_before(elr->lr_next_sched, next_wakeup))
3830 					next_wakeup = elr->lr_next_sched;
3831 				continue;
3832 			}
3833 			if (down_read_trylock(&elr->lr_super->s_umount)) {
3834 				if (sb_start_write_trylock(elr->lr_super)) {
3835 					progress = 1;
3836 					/*
3837 					 * We hold sb->s_umount, sb can not
3838 					 * be removed from the list, it is
3839 					 * now safe to drop li_list_mtx
3840 					 */
3841 					mutex_unlock(&eli->li_list_mtx);
3842 					err = ext4_run_li_request(elr);
3843 					sb_end_write(elr->lr_super);
3844 					mutex_lock(&eli->li_list_mtx);
3845 					n = pos->next;
3846 				}
3847 				up_read((&elr->lr_super->s_umount));
3848 			}
3849 			/* error, remove the lazy_init job */
3850 			if (err) {
3851 				ext4_remove_li_request(elr);
3852 				continue;
3853 			}
3854 			if (!progress) {
3855 				elr->lr_next_sched = jiffies +
3856 					get_random_u32_below(EXT4_DEF_LI_MAX_START_DELAY * HZ);
3857 			}
3858 			if (time_before(elr->lr_next_sched, next_wakeup))
3859 				next_wakeup = elr->lr_next_sched;
3860 		}
3861 		mutex_unlock(&eli->li_list_mtx);
3862 
3863 		try_to_freeze();
3864 
3865 		cur = jiffies;
3866 		if ((time_after_eq(cur, next_wakeup)) ||
3867 		    (MAX_JIFFY_OFFSET == next_wakeup)) {
3868 			cond_resched();
3869 			continue;
3870 		}
3871 
3872 		schedule_timeout_interruptible(next_wakeup - cur);
3873 
3874 		if (kthread_should_stop()) {
3875 			ext4_clear_request_list();
3876 			goto exit_thread;
3877 		}
3878 	}
3879 
3880 exit_thread:
3881 	/*
3882 	 * It looks like the request list is empty, but we need
3883 	 * to check it under the li_list_mtx lock, to prevent any
3884 	 * additions into it, and of course we should lock ext4_li_mtx
3885 	 * to atomically free the list and ext4_li_info, because at
3886 	 * this point another ext4 filesystem could be registering
3887 	 * new one.
3888 	 */
3889 	mutex_lock(&ext4_li_mtx);
3890 	mutex_lock(&eli->li_list_mtx);
3891 	if (!list_empty(&eli->li_request_list)) {
3892 		mutex_unlock(&eli->li_list_mtx);
3893 		mutex_unlock(&ext4_li_mtx);
3894 		goto cont_thread;
3895 	}
3896 	mutex_unlock(&eli->li_list_mtx);
3897 	kfree(ext4_li_info);
3898 	ext4_li_info = NULL;
3899 	mutex_unlock(&ext4_li_mtx);
3900 
3901 	return 0;
3902 }
3903 
ext4_clear_request_list(void)3904 static void ext4_clear_request_list(void)
3905 {
3906 	struct list_head *pos, *n;
3907 	struct ext4_li_request *elr;
3908 
3909 	mutex_lock(&ext4_li_info->li_list_mtx);
3910 	list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3911 		elr = list_entry(pos, struct ext4_li_request,
3912 				 lr_request);
3913 		ext4_remove_li_request(elr);
3914 	}
3915 	mutex_unlock(&ext4_li_info->li_list_mtx);
3916 }
3917 
ext4_run_lazyinit_thread(void)3918 static int ext4_run_lazyinit_thread(void)
3919 {
3920 	ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3921 					 ext4_li_info, "ext4lazyinit");
3922 	if (IS_ERR(ext4_lazyinit_task)) {
3923 		int err = PTR_ERR(ext4_lazyinit_task);
3924 		ext4_clear_request_list();
3925 		kfree(ext4_li_info);
3926 		ext4_li_info = NULL;
3927 		printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3928 				 "initialization thread\n",
3929 				 err);
3930 		return err;
3931 	}
3932 	ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3933 	return 0;
3934 }
3935 
3936 /*
3937  * Check whether it make sense to run itable init. thread or not.
3938  * If there is at least one uninitialized inode table, return
3939  * corresponding group number, else the loop goes through all
3940  * groups and return total number of groups.
3941  */
ext4_has_uninit_itable(struct super_block * sb)3942 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3943 {
3944 	ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3945 	struct ext4_group_desc *gdp = NULL;
3946 
3947 	if (!ext4_has_group_desc_csum(sb))
3948 		return ngroups;
3949 
3950 	for (group = 0; group < ngroups; group++) {
3951 		gdp = ext4_get_group_desc(sb, group, NULL);
3952 		if (!gdp)
3953 			continue;
3954 
3955 		if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3956 			break;
3957 	}
3958 
3959 	return group;
3960 }
3961 
ext4_li_info_new(void)3962 static int ext4_li_info_new(void)
3963 {
3964 	struct ext4_lazy_init *eli = NULL;
3965 
3966 	eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3967 	if (!eli)
3968 		return -ENOMEM;
3969 
3970 	INIT_LIST_HEAD(&eli->li_request_list);
3971 	mutex_init(&eli->li_list_mtx);
3972 
3973 	eli->li_state |= EXT4_LAZYINIT_QUIT;
3974 
3975 	ext4_li_info = eli;
3976 
3977 	return 0;
3978 }
3979 
ext4_li_request_new(struct super_block * sb,ext4_group_t start)3980 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3981 					    ext4_group_t start)
3982 {
3983 	struct ext4_li_request *elr;
3984 
3985 	elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3986 	if (!elr)
3987 		return NULL;
3988 
3989 	elr->lr_super = sb;
3990 	elr->lr_first_not_zeroed = start;
3991 	if (test_opt(sb, NO_PREFETCH_BLOCK_BITMAPS)) {
3992 		elr->lr_mode = EXT4_LI_MODE_ITABLE;
3993 		elr->lr_next_group = start;
3994 	} else {
3995 		elr->lr_mode = EXT4_LI_MODE_PREFETCH_BBITMAP;
3996 	}
3997 
3998 	/*
3999 	 * Randomize first schedule time of the request to
4000 	 * spread the inode table initialization requests
4001 	 * better.
4002 	 */
4003 	elr->lr_next_sched = jiffies + get_random_u32_below(EXT4_DEF_LI_MAX_START_DELAY * HZ);
4004 	return elr;
4005 }
4006 
ext4_register_li_request(struct super_block * sb,ext4_group_t first_not_zeroed)4007 int ext4_register_li_request(struct super_block *sb,
4008 			     ext4_group_t first_not_zeroed)
4009 {
4010 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4011 	struct ext4_li_request *elr = NULL;
4012 	ext4_group_t ngroups = sbi->s_groups_count;
4013 	int ret = 0;
4014 
4015 	mutex_lock(&ext4_li_mtx);
4016 	if (sbi->s_li_request != NULL) {
4017 		/*
4018 		 * Reset timeout so it can be computed again, because
4019 		 * s_li_wait_mult might have changed.
4020 		 */
4021 		sbi->s_li_request->lr_timeout = 0;
4022 		goto out;
4023 	}
4024 
4025 	if (sb_rdonly(sb) ||
4026 	    (test_opt(sb, NO_PREFETCH_BLOCK_BITMAPS) &&
4027 	     (first_not_zeroed == ngroups || !test_opt(sb, INIT_INODE_TABLE))))
4028 		goto out;
4029 
4030 	elr = ext4_li_request_new(sb, first_not_zeroed);
4031 	if (!elr) {
4032 		ret = -ENOMEM;
4033 		goto out;
4034 	}
4035 
4036 	if (NULL == ext4_li_info) {
4037 		ret = ext4_li_info_new();
4038 		if (ret)
4039 			goto out;
4040 	}
4041 
4042 	mutex_lock(&ext4_li_info->li_list_mtx);
4043 	list_add(&elr->lr_request, &ext4_li_info->li_request_list);
4044 	mutex_unlock(&ext4_li_info->li_list_mtx);
4045 
4046 	sbi->s_li_request = elr;
4047 	/*
4048 	 * set elr to NULL here since it has been inserted to
4049 	 * the request_list and the removal and free of it is
4050 	 * handled by ext4_clear_request_list from now on.
4051 	 */
4052 	elr = NULL;
4053 
4054 	if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
4055 		ret = ext4_run_lazyinit_thread();
4056 		if (ret)
4057 			goto out;
4058 	}
4059 out:
4060 	mutex_unlock(&ext4_li_mtx);
4061 	if (ret)
4062 		kfree(elr);
4063 	return ret;
4064 }
4065 
4066 /*
4067  * We do not need to lock anything since this is called on
4068  * module unload.
4069  */
ext4_destroy_lazyinit_thread(void)4070 static void ext4_destroy_lazyinit_thread(void)
4071 {
4072 	/*
4073 	 * If thread exited earlier
4074 	 * there's nothing to be done.
4075 	 */
4076 	if (!ext4_li_info || !ext4_lazyinit_task)
4077 		return;
4078 
4079 	kthread_stop(ext4_lazyinit_task);
4080 }
4081 
set_journal_csum_feature_set(struct super_block * sb)4082 static int set_journal_csum_feature_set(struct super_block *sb)
4083 {
4084 	int ret = 1;
4085 	int compat, incompat;
4086 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4087 
4088 	if (ext4_has_metadata_csum(sb)) {
4089 		/* journal checksum v3 */
4090 		compat = 0;
4091 		incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
4092 	} else {
4093 		/* journal checksum v1 */
4094 		compat = JBD2_FEATURE_COMPAT_CHECKSUM;
4095 		incompat = 0;
4096 	}
4097 
4098 	jbd2_journal_clear_features(sbi->s_journal,
4099 			JBD2_FEATURE_COMPAT_CHECKSUM, 0,
4100 			JBD2_FEATURE_INCOMPAT_CSUM_V3 |
4101 			JBD2_FEATURE_INCOMPAT_CSUM_V2);
4102 	if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4103 		ret = jbd2_journal_set_features(sbi->s_journal,
4104 				compat, 0,
4105 				JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
4106 				incompat);
4107 	} else if (test_opt(sb, JOURNAL_CHECKSUM)) {
4108 		ret = jbd2_journal_set_features(sbi->s_journal,
4109 				compat, 0,
4110 				incompat);
4111 		jbd2_journal_clear_features(sbi->s_journal, 0, 0,
4112 				JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
4113 	} else {
4114 		jbd2_journal_clear_features(sbi->s_journal, 0, 0,
4115 				JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
4116 	}
4117 
4118 	return ret;
4119 }
4120 
4121 /*
4122  * Note: calculating the overhead so we can be compatible with
4123  * historical BSD practice is quite difficult in the face of
4124  * clusters/bigalloc.  This is because multiple metadata blocks from
4125  * different block group can end up in the same allocation cluster.
4126  * Calculating the exact overhead in the face of clustered allocation
4127  * requires either O(all block bitmaps) in memory or O(number of block
4128  * groups**2) in time.  We will still calculate the superblock for
4129  * older file systems --- and if we come across with a bigalloc file
4130  * system with zero in s_overhead_clusters the estimate will be close to
4131  * correct especially for very large cluster sizes --- but for newer
4132  * file systems, it's better to calculate this figure once at mkfs
4133  * time, and store it in the superblock.  If the superblock value is
4134  * present (even for non-bigalloc file systems), we will use it.
4135  */
count_overhead(struct super_block * sb,ext4_group_t grp,char * buf)4136 static int count_overhead(struct super_block *sb, ext4_group_t grp,
4137 			  char *buf)
4138 {
4139 	struct ext4_sb_info	*sbi = EXT4_SB(sb);
4140 	struct ext4_group_desc	*gdp;
4141 	ext4_fsblk_t		first_block, last_block, b;
4142 	ext4_group_t		i, ngroups = ext4_get_groups_count(sb);
4143 	int			s, j, count = 0;
4144 	int			has_super = ext4_bg_has_super(sb, grp);
4145 
4146 	if (!ext4_has_feature_bigalloc(sb))
4147 		return (has_super + ext4_bg_num_gdb(sb, grp) +
4148 			(has_super ? le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) : 0) +
4149 			sbi->s_itb_per_group + 2);
4150 
4151 	first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
4152 		(grp * EXT4_BLOCKS_PER_GROUP(sb));
4153 	last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
4154 	for (i = 0; i < ngroups; i++) {
4155 		gdp = ext4_get_group_desc(sb, i, NULL);
4156 		b = ext4_block_bitmap(sb, gdp);
4157 		if (b >= first_block && b <= last_block) {
4158 			ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
4159 			count++;
4160 		}
4161 		b = ext4_inode_bitmap(sb, gdp);
4162 		if (b >= first_block && b <= last_block) {
4163 			ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
4164 			count++;
4165 		}
4166 		b = ext4_inode_table(sb, gdp);
4167 		if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
4168 			for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
4169 				int c = EXT4_B2C(sbi, b - first_block);
4170 				ext4_set_bit(c, buf);
4171 				count++;
4172 			}
4173 		if (i != grp)
4174 			continue;
4175 		s = 0;
4176 		if (ext4_bg_has_super(sb, grp)) {
4177 			ext4_set_bit(s++, buf);
4178 			count++;
4179 		}
4180 		j = ext4_bg_num_gdb(sb, grp);
4181 		if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
4182 			ext4_error(sb, "Invalid number of block group "
4183 				   "descriptor blocks: %d", j);
4184 			j = EXT4_BLOCKS_PER_GROUP(sb) - s;
4185 		}
4186 		count += j;
4187 		for (; j > 0; j--)
4188 			ext4_set_bit(EXT4_B2C(sbi, s++), buf);
4189 	}
4190 	if (!count)
4191 		return 0;
4192 	return EXT4_CLUSTERS_PER_GROUP(sb) -
4193 		ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
4194 }
4195 
4196 /*
4197  * Compute the overhead and stash it in sbi->s_overhead
4198  */
ext4_calculate_overhead(struct super_block * sb)4199 int ext4_calculate_overhead(struct super_block *sb)
4200 {
4201 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4202 	struct ext4_super_block *es = sbi->s_es;
4203 	struct inode *j_inode;
4204 	unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
4205 	ext4_group_t i, ngroups = ext4_get_groups_count(sb);
4206 	ext4_fsblk_t overhead = 0;
4207 	char *buf = (char *) get_zeroed_page(GFP_NOFS);
4208 
4209 	if (!buf)
4210 		return -ENOMEM;
4211 
4212 	/*
4213 	 * Compute the overhead (FS structures).  This is constant
4214 	 * for a given filesystem unless the number of block groups
4215 	 * changes so we cache the previous value until it does.
4216 	 */
4217 
4218 	/*
4219 	 * All of the blocks before first_data_block are overhead
4220 	 */
4221 	overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
4222 
4223 	/*
4224 	 * Add the overhead found in each block group
4225 	 */
4226 	for (i = 0; i < ngroups; i++) {
4227 		int blks;
4228 
4229 		blks = count_overhead(sb, i, buf);
4230 		overhead += blks;
4231 		if (blks)
4232 			memset(buf, 0, PAGE_SIZE);
4233 		cond_resched();
4234 	}
4235 
4236 	/*
4237 	 * Add the internal journal blocks whether the journal has been
4238 	 * loaded or not
4239 	 */
4240 	if (sbi->s_journal && !sbi->s_journal_bdev)
4241 		overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_total_len);
4242 	else if (ext4_has_feature_journal(sb) && !sbi->s_journal && j_inum) {
4243 		/* j_inum for internal journal is non-zero */
4244 		j_inode = ext4_get_journal_inode(sb, j_inum);
4245 		if (!IS_ERR(j_inode)) {
4246 			j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
4247 			overhead += EXT4_NUM_B2C(sbi, j_blocks);
4248 			iput(j_inode);
4249 		} else {
4250 			ext4_msg(sb, KERN_ERR, "can't get journal size");
4251 		}
4252 	}
4253 	sbi->s_overhead = overhead;
4254 	smp_wmb();
4255 	free_page((unsigned long) buf);
4256 	return 0;
4257 }
4258 
ext4_set_resv_clusters(struct super_block * sb)4259 static void ext4_set_resv_clusters(struct super_block *sb)
4260 {
4261 	ext4_fsblk_t resv_clusters;
4262 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4263 
4264 	/*
4265 	 * There's no need to reserve anything when we aren't using extents.
4266 	 * The space estimates are exact, there are no unwritten extents,
4267 	 * hole punching doesn't need new metadata... This is needed especially
4268 	 * to keep ext2/3 backward compatibility.
4269 	 */
4270 	if (!ext4_has_feature_extents(sb))
4271 		return;
4272 	/*
4273 	 * By default we reserve 2% or 4096 clusters, whichever is smaller.
4274 	 * This should cover the situations where we can not afford to run
4275 	 * out of space like for example punch hole, or converting
4276 	 * unwritten extents in delalloc path. In most cases such
4277 	 * allocation would require 1, or 2 blocks, higher numbers are
4278 	 * very rare.
4279 	 */
4280 	resv_clusters = (ext4_blocks_count(sbi->s_es) >>
4281 			 sbi->s_cluster_bits);
4282 
4283 	do_div(resv_clusters, 50);
4284 	resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
4285 
4286 	atomic64_set(&sbi->s_resv_clusters, resv_clusters);
4287 }
4288 
ext4_quota_mode(struct super_block * sb)4289 static const char *ext4_quota_mode(struct super_block *sb)
4290 {
4291 #ifdef CONFIG_QUOTA
4292 	if (!ext4_quota_capable(sb))
4293 		return "none";
4294 
4295 	if (EXT4_SB(sb)->s_journal && ext4_is_quota_journalled(sb))
4296 		return "journalled";
4297 	else
4298 		return "writeback";
4299 #else
4300 	return "disabled";
4301 #endif
4302 }
4303 
ext4_setup_csum_trigger(struct super_block * sb,enum ext4_journal_trigger_type type,void (* trigger)(struct jbd2_buffer_trigger_type * type,struct buffer_head * bh,void * mapped_data,size_t size))4304 static void ext4_setup_csum_trigger(struct super_block *sb,
4305 				    enum ext4_journal_trigger_type type,
4306 				    void (*trigger)(
4307 					struct jbd2_buffer_trigger_type *type,
4308 					struct buffer_head *bh,
4309 					void *mapped_data,
4310 					size_t size))
4311 {
4312 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4313 
4314 	sbi->s_journal_triggers[type].sb = sb;
4315 	sbi->s_journal_triggers[type].tr_triggers.t_frozen = trigger;
4316 }
4317 
ext4_free_sbi(struct ext4_sb_info * sbi)4318 static void ext4_free_sbi(struct ext4_sb_info *sbi)
4319 {
4320 	if (!sbi)
4321 		return;
4322 
4323 	kfree(sbi->s_blockgroup_lock);
4324 	fs_put_dax(sbi->s_daxdev, NULL);
4325 	kfree(sbi);
4326 }
4327 
ext4_alloc_sbi(struct super_block * sb)4328 static struct ext4_sb_info *ext4_alloc_sbi(struct super_block *sb)
4329 {
4330 	struct ext4_sb_info *sbi;
4331 
4332 	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
4333 	if (!sbi)
4334 		return NULL;
4335 
4336 	sbi->s_daxdev = fs_dax_get_by_bdev(sb->s_bdev, &sbi->s_dax_part_off,
4337 					   NULL, NULL);
4338 
4339 	sbi->s_blockgroup_lock =
4340 		kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
4341 
4342 	if (!sbi->s_blockgroup_lock)
4343 		goto err_out;
4344 
4345 	sb->s_fs_info = sbi;
4346 	sbi->s_sb = sb;
4347 	return sbi;
4348 err_out:
4349 	fs_put_dax(sbi->s_daxdev, NULL);
4350 	kfree(sbi);
4351 	return NULL;
4352 }
4353 
ext4_set_def_opts(struct super_block * sb,struct ext4_super_block * es)4354 static void ext4_set_def_opts(struct super_block *sb,
4355 			      struct ext4_super_block *es)
4356 {
4357 	unsigned long def_mount_opts;
4358 
4359 	/* Set defaults before we parse the mount options */
4360 	def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
4361 	set_opt(sb, INIT_INODE_TABLE);
4362 	if (def_mount_opts & EXT4_DEFM_DEBUG)
4363 		set_opt(sb, DEBUG);
4364 	if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
4365 		set_opt(sb, GRPID);
4366 	if (def_mount_opts & EXT4_DEFM_UID16)
4367 		set_opt(sb, NO_UID32);
4368 	/* xattr user namespace & acls are now defaulted on */
4369 	set_opt(sb, XATTR_USER);
4370 #ifdef CONFIG_EXT4_FS_POSIX_ACL
4371 	set_opt(sb, POSIX_ACL);
4372 #endif
4373 	if (ext4_has_feature_fast_commit(sb))
4374 		set_opt2(sb, JOURNAL_FAST_COMMIT);
4375 	/* don't forget to enable journal_csum when metadata_csum is enabled. */
4376 	if (ext4_has_metadata_csum(sb))
4377 		set_opt(sb, JOURNAL_CHECKSUM);
4378 
4379 	if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
4380 		set_opt(sb, JOURNAL_DATA);
4381 	else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
4382 		set_opt(sb, ORDERED_DATA);
4383 	else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
4384 		set_opt(sb, WRITEBACK_DATA);
4385 
4386 	if (le16_to_cpu(es->s_errors) == EXT4_ERRORS_PANIC)
4387 		set_opt(sb, ERRORS_PANIC);
4388 	else if (le16_to_cpu(es->s_errors) == EXT4_ERRORS_CONTINUE)
4389 		set_opt(sb, ERRORS_CONT);
4390 	else
4391 		set_opt(sb, ERRORS_RO);
4392 	/* block_validity enabled by default; disable with noblock_validity */
4393 	set_opt(sb, BLOCK_VALIDITY);
4394 	if (def_mount_opts & EXT4_DEFM_DISCARD)
4395 		set_opt(sb, DISCARD);
4396 
4397 	if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
4398 		set_opt(sb, BARRIER);
4399 
4400 	/*
4401 	 * enable delayed allocation by default
4402 	 * Use -o nodelalloc to turn it off
4403 	 */
4404 	if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
4405 	    ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
4406 		set_opt(sb, DELALLOC);
4407 
4408 	if (sb->s_blocksize == PAGE_SIZE)
4409 		set_opt(sb, DIOREAD_NOLOCK);
4410 }
4411 
ext4_handle_clustersize(struct super_block * sb)4412 static int ext4_handle_clustersize(struct super_block *sb)
4413 {
4414 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4415 	struct ext4_super_block *es = sbi->s_es;
4416 	int clustersize;
4417 
4418 	/* Handle clustersize */
4419 	clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
4420 	if (ext4_has_feature_bigalloc(sb)) {
4421 		if (clustersize < sb->s_blocksize) {
4422 			ext4_msg(sb, KERN_ERR,
4423 				 "cluster size (%d) smaller than "
4424 				 "block size (%lu)", clustersize, sb->s_blocksize);
4425 			return -EINVAL;
4426 		}
4427 		sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
4428 			le32_to_cpu(es->s_log_block_size);
4429 		sbi->s_clusters_per_group =
4430 			le32_to_cpu(es->s_clusters_per_group);
4431 		if (sbi->s_clusters_per_group > sb->s_blocksize * 8) {
4432 			ext4_msg(sb, KERN_ERR,
4433 				 "#clusters per group too big: %lu",
4434 				 sbi->s_clusters_per_group);
4435 			return -EINVAL;
4436 		}
4437 		if (sbi->s_blocks_per_group !=
4438 		    (sbi->s_clusters_per_group * (clustersize / sb->s_blocksize))) {
4439 			ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
4440 				 "clusters per group (%lu) inconsistent",
4441 				 sbi->s_blocks_per_group,
4442 				 sbi->s_clusters_per_group);
4443 			return -EINVAL;
4444 		}
4445 	} else {
4446 		if (clustersize != sb->s_blocksize) {
4447 			ext4_msg(sb, KERN_ERR,
4448 				 "fragment/cluster size (%d) != "
4449 				 "block size (%lu)", clustersize, sb->s_blocksize);
4450 			return -EINVAL;
4451 		}
4452 		if (sbi->s_blocks_per_group > sb->s_blocksize * 8) {
4453 			ext4_msg(sb, KERN_ERR,
4454 				 "#blocks per group too big: %lu",
4455 				 sbi->s_blocks_per_group);
4456 			return -EINVAL;
4457 		}
4458 		sbi->s_clusters_per_group = sbi->s_blocks_per_group;
4459 		sbi->s_cluster_bits = 0;
4460 	}
4461 	sbi->s_cluster_ratio = clustersize / sb->s_blocksize;
4462 
4463 	/* Do we have standard group size of clustersize * 8 blocks ? */
4464 	if (sbi->s_blocks_per_group == clustersize << 3)
4465 		set_opt2(sb, STD_GROUP_SIZE);
4466 
4467 	return 0;
4468 }
4469 
ext4_fast_commit_init(struct super_block * sb)4470 static void ext4_fast_commit_init(struct super_block *sb)
4471 {
4472 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4473 
4474 	/* Initialize fast commit stuff */
4475 	atomic_set(&sbi->s_fc_subtid, 0);
4476 	INIT_LIST_HEAD(&sbi->s_fc_q[FC_Q_MAIN]);
4477 	INIT_LIST_HEAD(&sbi->s_fc_q[FC_Q_STAGING]);
4478 	INIT_LIST_HEAD(&sbi->s_fc_dentry_q[FC_Q_MAIN]);
4479 	INIT_LIST_HEAD(&sbi->s_fc_dentry_q[FC_Q_STAGING]);
4480 	sbi->s_fc_bytes = 0;
4481 	ext4_clear_mount_flag(sb, EXT4_MF_FC_INELIGIBLE);
4482 	sbi->s_fc_ineligible_tid = 0;
4483 	spin_lock_init(&sbi->s_fc_lock);
4484 	memset(&sbi->s_fc_stats, 0, sizeof(sbi->s_fc_stats));
4485 	sbi->s_fc_replay_state.fc_regions = NULL;
4486 	sbi->s_fc_replay_state.fc_regions_size = 0;
4487 	sbi->s_fc_replay_state.fc_regions_used = 0;
4488 	sbi->s_fc_replay_state.fc_regions_valid = 0;
4489 	sbi->s_fc_replay_state.fc_modified_inodes = NULL;
4490 	sbi->s_fc_replay_state.fc_modified_inodes_size = 0;
4491 	sbi->s_fc_replay_state.fc_modified_inodes_used = 0;
4492 }
4493 
ext4_inode_info_init(struct super_block * sb,struct ext4_super_block * es)4494 static int ext4_inode_info_init(struct super_block *sb,
4495 				struct ext4_super_block *es)
4496 {
4497 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4498 
4499 	if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
4500 		sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
4501 		sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
4502 	} else {
4503 		sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
4504 		sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
4505 		if (sbi->s_first_ino < EXT4_GOOD_OLD_FIRST_INO) {
4506 			ext4_msg(sb, KERN_ERR, "invalid first ino: %u",
4507 				 sbi->s_first_ino);
4508 			return -EINVAL;
4509 		}
4510 		if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
4511 		    (!is_power_of_2(sbi->s_inode_size)) ||
4512 		    (sbi->s_inode_size > sb->s_blocksize)) {
4513 			ext4_msg(sb, KERN_ERR,
4514 			       "unsupported inode size: %d",
4515 			       sbi->s_inode_size);
4516 			ext4_msg(sb, KERN_ERR, "blocksize: %lu", sb->s_blocksize);
4517 			return -EINVAL;
4518 		}
4519 		/*
4520 		 * i_atime_extra is the last extra field available for
4521 		 * [acm]times in struct ext4_inode. Checking for that
4522 		 * field should suffice to ensure we have extra space
4523 		 * for all three.
4524 		 */
4525 		if (sbi->s_inode_size >= offsetof(struct ext4_inode, i_atime_extra) +
4526 			sizeof(((struct ext4_inode *)0)->i_atime_extra)) {
4527 			sb->s_time_gran = 1;
4528 			sb->s_time_max = EXT4_EXTRA_TIMESTAMP_MAX;
4529 		} else {
4530 			sb->s_time_gran = NSEC_PER_SEC;
4531 			sb->s_time_max = EXT4_NON_EXTRA_TIMESTAMP_MAX;
4532 		}
4533 		sb->s_time_min = EXT4_TIMESTAMP_MIN;
4534 	}
4535 
4536 	if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
4537 		sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4538 			EXT4_GOOD_OLD_INODE_SIZE;
4539 		if (ext4_has_feature_extra_isize(sb)) {
4540 			unsigned v, max = (sbi->s_inode_size -
4541 					   EXT4_GOOD_OLD_INODE_SIZE);
4542 
4543 			v = le16_to_cpu(es->s_want_extra_isize);
4544 			if (v > max) {
4545 				ext4_msg(sb, KERN_ERR,
4546 					 "bad s_want_extra_isize: %d", v);
4547 				return -EINVAL;
4548 			}
4549 			if (sbi->s_want_extra_isize < v)
4550 				sbi->s_want_extra_isize = v;
4551 
4552 			v = le16_to_cpu(es->s_min_extra_isize);
4553 			if (v > max) {
4554 				ext4_msg(sb, KERN_ERR,
4555 					 "bad s_min_extra_isize: %d", v);
4556 				return -EINVAL;
4557 			}
4558 			if (sbi->s_want_extra_isize < v)
4559 				sbi->s_want_extra_isize = v;
4560 		}
4561 	}
4562 
4563 	return 0;
4564 }
4565 
4566 #if IS_ENABLED(CONFIG_UNICODE)
ext4_encoding_init(struct super_block * sb,struct ext4_super_block * es)4567 static int ext4_encoding_init(struct super_block *sb, struct ext4_super_block *es)
4568 {
4569 	const struct ext4_sb_encodings *encoding_info;
4570 	struct unicode_map *encoding;
4571 	__u16 encoding_flags = le16_to_cpu(es->s_encoding_flags);
4572 
4573 	if (!ext4_has_feature_casefold(sb) || sb->s_encoding)
4574 		return 0;
4575 
4576 	encoding_info = ext4_sb_read_encoding(es);
4577 	if (!encoding_info) {
4578 		ext4_msg(sb, KERN_ERR,
4579 			"Encoding requested by superblock is unknown");
4580 		return -EINVAL;
4581 	}
4582 
4583 	encoding = utf8_load(encoding_info->version);
4584 	if (IS_ERR(encoding)) {
4585 		ext4_msg(sb, KERN_ERR,
4586 			"can't mount with superblock charset: %s-%u.%u.%u "
4587 			"not supported by the kernel. flags: 0x%x.",
4588 			encoding_info->name,
4589 			unicode_major(encoding_info->version),
4590 			unicode_minor(encoding_info->version),
4591 			unicode_rev(encoding_info->version),
4592 			encoding_flags);
4593 		return -EINVAL;
4594 	}
4595 	ext4_msg(sb, KERN_INFO,"Using encoding defined by superblock: "
4596 		"%s-%u.%u.%u with flags 0x%hx", encoding_info->name,
4597 		unicode_major(encoding_info->version),
4598 		unicode_minor(encoding_info->version),
4599 		unicode_rev(encoding_info->version),
4600 		encoding_flags);
4601 
4602 	sb->s_encoding = encoding;
4603 	sb->s_encoding_flags = encoding_flags;
4604 
4605 	return 0;
4606 }
4607 #else
ext4_encoding_init(struct super_block * sb,struct ext4_super_block * es)4608 static inline int ext4_encoding_init(struct super_block *sb, struct ext4_super_block *es)
4609 {
4610 	return 0;
4611 }
4612 #endif
4613 
ext4_init_metadata_csum(struct super_block * sb,struct ext4_super_block * es)4614 static int ext4_init_metadata_csum(struct super_block *sb, struct ext4_super_block *es)
4615 {
4616 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4617 
4618 	/* Warn if metadata_csum and gdt_csum are both set. */
4619 	if (ext4_has_feature_metadata_csum(sb) &&
4620 	    ext4_has_feature_gdt_csum(sb))
4621 		ext4_warning(sb, "metadata_csum and uninit_bg are "
4622 			     "redundant flags; please run fsck.");
4623 
4624 	/* Check for a known checksum algorithm */
4625 	if (!ext4_verify_csum_type(sb, es)) {
4626 		ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4627 			 "unknown checksum algorithm.");
4628 		return -EINVAL;
4629 	}
4630 	ext4_setup_csum_trigger(sb, EXT4_JTR_ORPHAN_FILE,
4631 				ext4_orphan_file_block_trigger);
4632 
4633 	/* Load the checksum driver */
4634 	sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
4635 	if (IS_ERR(sbi->s_chksum_driver)) {
4636 		int ret = PTR_ERR(sbi->s_chksum_driver);
4637 		ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
4638 		sbi->s_chksum_driver = NULL;
4639 		return ret;
4640 	}
4641 
4642 	/* Check superblock checksum */
4643 	if (!ext4_superblock_csum_verify(sb, es)) {
4644 		ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4645 			 "invalid superblock checksum.  Run e2fsck?");
4646 		return -EFSBADCRC;
4647 	}
4648 
4649 	/* Precompute checksum seed for all metadata */
4650 	if (ext4_has_feature_csum_seed(sb))
4651 		sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
4652 	else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
4653 		sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
4654 					       sizeof(es->s_uuid));
4655 	return 0;
4656 }
4657 
ext4_check_feature_compatibility(struct super_block * sb,struct ext4_super_block * es,int silent)4658 static int ext4_check_feature_compatibility(struct super_block *sb,
4659 					    struct ext4_super_block *es,
4660 					    int silent)
4661 {
4662 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4663 
4664 	if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
4665 	    (ext4_has_compat_features(sb) ||
4666 	     ext4_has_ro_compat_features(sb) ||
4667 	     ext4_has_incompat_features(sb)))
4668 		ext4_msg(sb, KERN_WARNING,
4669 		       "feature flags set on rev 0 fs, "
4670 		       "running e2fsck is recommended");
4671 
4672 	if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
4673 		set_opt2(sb, HURD_COMPAT);
4674 		if (ext4_has_feature_64bit(sb)) {
4675 			ext4_msg(sb, KERN_ERR,
4676 				 "The Hurd can't support 64-bit file systems");
4677 			return -EINVAL;
4678 		}
4679 
4680 		/*
4681 		 * ea_inode feature uses l_i_version field which is not
4682 		 * available in HURD_COMPAT mode.
4683 		 */
4684 		if (ext4_has_feature_ea_inode(sb)) {
4685 			ext4_msg(sb, KERN_ERR,
4686 				 "ea_inode feature is not supported for Hurd");
4687 			return -EINVAL;
4688 		}
4689 	}
4690 
4691 	if (IS_EXT2_SB(sb)) {
4692 		if (ext2_feature_set_ok(sb))
4693 			ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
4694 				 "using the ext4 subsystem");
4695 		else {
4696 			/*
4697 			 * If we're probing be silent, if this looks like
4698 			 * it's actually an ext[34] filesystem.
4699 			 */
4700 			if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4701 				return -EINVAL;
4702 			ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
4703 				 "to feature incompatibilities");
4704 			return -EINVAL;
4705 		}
4706 	}
4707 
4708 	if (IS_EXT3_SB(sb)) {
4709 		if (ext3_feature_set_ok(sb))
4710 			ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
4711 				 "using the ext4 subsystem");
4712 		else {
4713 			/*
4714 			 * If we're probing be silent, if this looks like
4715 			 * it's actually an ext4 filesystem.
4716 			 */
4717 			if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4718 				return -EINVAL;
4719 			ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
4720 				 "to feature incompatibilities");
4721 			return -EINVAL;
4722 		}
4723 	}
4724 
4725 	/*
4726 	 * Check feature flags regardless of the revision level, since we
4727 	 * previously didn't change the revision level when setting the flags,
4728 	 * so there is a chance incompat flags are set on a rev 0 filesystem.
4729 	 */
4730 	if (!ext4_feature_set_ok(sb, (sb_rdonly(sb))))
4731 		return -EINVAL;
4732 
4733 	if (sbi->s_daxdev) {
4734 		if (sb->s_blocksize == PAGE_SIZE)
4735 			set_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags);
4736 		else
4737 			ext4_msg(sb, KERN_ERR, "unsupported blocksize for DAX\n");
4738 	}
4739 
4740 	if (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) {
4741 		if (ext4_has_feature_inline_data(sb)) {
4742 			ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
4743 					" that may contain inline data");
4744 			return -EINVAL;
4745 		}
4746 		if (!test_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags)) {
4747 			ext4_msg(sb, KERN_ERR,
4748 				"DAX unsupported by block device.");
4749 			return -EINVAL;
4750 		}
4751 	}
4752 
4753 	if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
4754 		ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
4755 			 es->s_encryption_level);
4756 		return -EINVAL;
4757 	}
4758 
4759 	return 0;
4760 }
4761 
ext4_check_geometry(struct super_block * sb,struct ext4_super_block * es)4762 static int ext4_check_geometry(struct super_block *sb,
4763 			       struct ext4_super_block *es)
4764 {
4765 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4766 	__u64 blocks_count;
4767 	int err;
4768 
4769 	if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (sb->s_blocksize / 4)) {
4770 		ext4_msg(sb, KERN_ERR,
4771 			 "Number of reserved GDT blocks insanely large: %d",
4772 			 le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
4773 		return -EINVAL;
4774 	}
4775 	/*
4776 	 * Test whether we have more sectors than will fit in sector_t,
4777 	 * and whether the max offset is addressable by the page cache.
4778 	 */
4779 	err = generic_check_addressable(sb->s_blocksize_bits,
4780 					ext4_blocks_count(es));
4781 	if (err) {
4782 		ext4_msg(sb, KERN_ERR, "filesystem"
4783 			 " too large to mount safely on this system");
4784 		return err;
4785 	}
4786 
4787 	/* check blocks count against device size */
4788 	blocks_count = sb_bdev_nr_blocks(sb);
4789 	if (blocks_count && ext4_blocks_count(es) > blocks_count) {
4790 		ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
4791 		       "exceeds size of device (%llu blocks)",
4792 		       ext4_blocks_count(es), blocks_count);
4793 		return -EINVAL;
4794 	}
4795 
4796 	/*
4797 	 * It makes no sense for the first data block to be beyond the end
4798 	 * of the filesystem.
4799 	 */
4800 	if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
4801 		ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4802 			 "block %u is beyond end of filesystem (%llu)",
4803 			 le32_to_cpu(es->s_first_data_block),
4804 			 ext4_blocks_count(es));
4805 		return -EINVAL;
4806 	}
4807 	if ((es->s_first_data_block == 0) && (es->s_log_block_size == 0) &&
4808 	    (sbi->s_cluster_ratio == 1)) {
4809 		ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4810 			 "block is 0 with a 1k block and cluster size");
4811 		return -EINVAL;
4812 	}
4813 
4814 	blocks_count = (ext4_blocks_count(es) -
4815 			le32_to_cpu(es->s_first_data_block) +
4816 			EXT4_BLOCKS_PER_GROUP(sb) - 1);
4817 	do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
4818 	if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
4819 		ext4_msg(sb, KERN_WARNING, "groups count too large: %llu "
4820 		       "(block count %llu, first data block %u, "
4821 		       "blocks per group %lu)", blocks_count,
4822 		       ext4_blocks_count(es),
4823 		       le32_to_cpu(es->s_first_data_block),
4824 		       EXT4_BLOCKS_PER_GROUP(sb));
4825 		return -EINVAL;
4826 	}
4827 	sbi->s_groups_count = blocks_count;
4828 	sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
4829 			(EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
4830 	if (((u64)sbi->s_groups_count * sbi->s_inodes_per_group) !=
4831 	    le32_to_cpu(es->s_inodes_count)) {
4832 		ext4_msg(sb, KERN_ERR, "inodes count not valid: %u vs %llu",
4833 			 le32_to_cpu(es->s_inodes_count),
4834 			 ((u64)sbi->s_groups_count * sbi->s_inodes_per_group));
4835 		return -EINVAL;
4836 	}
4837 
4838 	return 0;
4839 }
4840 
ext4_group_desc_init(struct super_block * sb,struct ext4_super_block * es,ext4_fsblk_t logical_sb_block,ext4_group_t * first_not_zeroed)4841 static int ext4_group_desc_init(struct super_block *sb,
4842 				struct ext4_super_block *es,
4843 				ext4_fsblk_t logical_sb_block,
4844 				ext4_group_t *first_not_zeroed)
4845 {
4846 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4847 	unsigned int db_count;
4848 	ext4_fsblk_t block;
4849 	int i;
4850 
4851 	db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
4852 		   EXT4_DESC_PER_BLOCK(sb);
4853 	if (ext4_has_feature_meta_bg(sb)) {
4854 		if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
4855 			ext4_msg(sb, KERN_WARNING,
4856 				 "first meta block group too large: %u "
4857 				 "(group descriptor block count %u)",
4858 				 le32_to_cpu(es->s_first_meta_bg), db_count);
4859 			return -EINVAL;
4860 		}
4861 	}
4862 	rcu_assign_pointer(sbi->s_group_desc,
4863 			   kvmalloc_array(db_count,
4864 					  sizeof(struct buffer_head *),
4865 					  GFP_KERNEL));
4866 	if (sbi->s_group_desc == NULL) {
4867 		ext4_msg(sb, KERN_ERR, "not enough memory");
4868 		return -ENOMEM;
4869 	}
4870 
4871 	bgl_lock_init(sbi->s_blockgroup_lock);
4872 
4873 	/* Pre-read the descriptors into the buffer cache */
4874 	for (i = 0; i < db_count; i++) {
4875 		block = descriptor_loc(sb, logical_sb_block, i);
4876 		ext4_sb_breadahead_unmovable(sb, block);
4877 	}
4878 
4879 	for (i = 0; i < db_count; i++) {
4880 		struct buffer_head *bh;
4881 
4882 		block = descriptor_loc(sb, logical_sb_block, i);
4883 		bh = ext4_sb_bread_unmovable(sb, block);
4884 		if (IS_ERR(bh)) {
4885 			ext4_msg(sb, KERN_ERR,
4886 			       "can't read group descriptor %d", i);
4887 			sbi->s_gdb_count = i;
4888 			return PTR_ERR(bh);
4889 		}
4890 		rcu_read_lock();
4891 		rcu_dereference(sbi->s_group_desc)[i] = bh;
4892 		rcu_read_unlock();
4893 	}
4894 	sbi->s_gdb_count = db_count;
4895 	if (!ext4_check_descriptors(sb, logical_sb_block, first_not_zeroed)) {
4896 		ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
4897 		return -EFSCORRUPTED;
4898 	}
4899 
4900 	return 0;
4901 }
4902 
ext4_load_and_init_journal(struct super_block * sb,struct ext4_super_block * es,struct ext4_fs_context * ctx)4903 static int ext4_load_and_init_journal(struct super_block *sb,
4904 				      struct ext4_super_block *es,
4905 				      struct ext4_fs_context *ctx)
4906 {
4907 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4908 	int err;
4909 
4910 	err = ext4_load_journal(sb, es, ctx->journal_devnum);
4911 	if (err)
4912 		return err;
4913 
4914 	if (ext4_has_feature_64bit(sb) &&
4915 	    !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4916 				       JBD2_FEATURE_INCOMPAT_64BIT)) {
4917 		ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4918 		goto out;
4919 	}
4920 
4921 	if (!set_journal_csum_feature_set(sb)) {
4922 		ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4923 			 "feature set");
4924 		goto out;
4925 	}
4926 
4927 	if (test_opt2(sb, JOURNAL_FAST_COMMIT) &&
4928 		!jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4929 					  JBD2_FEATURE_INCOMPAT_FAST_COMMIT)) {
4930 		ext4_msg(sb, KERN_ERR,
4931 			"Failed to set fast commit journal feature");
4932 		goto out;
4933 	}
4934 
4935 	/* We have now updated the journal if required, so we can
4936 	 * validate the data journaling mode. */
4937 	switch (test_opt(sb, DATA_FLAGS)) {
4938 	case 0:
4939 		/* No mode set, assume a default based on the journal
4940 		 * capabilities: ORDERED_DATA if the journal can
4941 		 * cope, else JOURNAL_DATA
4942 		 */
4943 		if (jbd2_journal_check_available_features
4944 		    (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4945 			set_opt(sb, ORDERED_DATA);
4946 			sbi->s_def_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
4947 		} else {
4948 			set_opt(sb, JOURNAL_DATA);
4949 			sbi->s_def_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
4950 		}
4951 		break;
4952 
4953 	case EXT4_MOUNT_ORDERED_DATA:
4954 	case EXT4_MOUNT_WRITEBACK_DATA:
4955 		if (!jbd2_journal_check_available_features
4956 		    (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4957 			ext4_msg(sb, KERN_ERR, "Journal does not support "
4958 			       "requested data journaling mode");
4959 			goto out;
4960 		}
4961 		break;
4962 	default:
4963 		break;
4964 	}
4965 
4966 	if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
4967 	    test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4968 		ext4_msg(sb, KERN_ERR, "can't mount with "
4969 			"journal_async_commit in data=ordered mode");
4970 		goto out;
4971 	}
4972 
4973 	set_task_ioprio(sbi->s_journal->j_task, ctx->journal_ioprio);
4974 
4975 	sbi->s_journal->j_submit_inode_data_buffers =
4976 		ext4_journal_submit_inode_data_buffers;
4977 	sbi->s_journal->j_finish_inode_data_buffers =
4978 		ext4_journal_finish_inode_data_buffers;
4979 
4980 	return 0;
4981 
4982 out:
4983 	/* flush s_sb_upd_work before destroying the journal. */
4984 	flush_work(&sbi->s_sb_upd_work);
4985 	jbd2_journal_destroy(sbi->s_journal);
4986 	sbi->s_journal = NULL;
4987 	return -EINVAL;
4988 }
4989 
ext4_check_journal_data_mode(struct super_block * sb)4990 static int ext4_check_journal_data_mode(struct super_block *sb)
4991 {
4992 	if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
4993 		printk_once(KERN_WARNING "EXT4-fs: Warning: mounting with "
4994 			    "data=journal disables delayed allocation, "
4995 			    "dioread_nolock, O_DIRECT and fast_commit support!\n");
4996 		/* can't mount with both data=journal and dioread_nolock. */
4997 		clear_opt(sb, DIOREAD_NOLOCK);
4998 		clear_opt2(sb, JOURNAL_FAST_COMMIT);
4999 		if (test_opt2(sb, EXPLICIT_DELALLOC)) {
5000 			ext4_msg(sb, KERN_ERR, "can't mount with "
5001 				 "both data=journal and delalloc");
5002 			return -EINVAL;
5003 		}
5004 		if (test_opt(sb, DAX_ALWAYS)) {
5005 			ext4_msg(sb, KERN_ERR, "can't mount with "
5006 				 "both data=journal and dax");
5007 			return -EINVAL;
5008 		}
5009 		if (ext4_has_feature_encrypt(sb)) {
5010 			ext4_msg(sb, KERN_WARNING,
5011 				 "encrypted files will use data=ordered "
5012 				 "instead of data journaling mode");
5013 		}
5014 		if (test_opt(sb, DELALLOC))
5015 			clear_opt(sb, DELALLOC);
5016 	} else {
5017 		sb->s_iflags |= SB_I_CGROUPWB;
5018 	}
5019 
5020 	return 0;
5021 }
5022 
ext4_load_super(struct super_block * sb,ext4_fsblk_t * lsb,int silent)5023 static int ext4_load_super(struct super_block *sb, ext4_fsblk_t *lsb,
5024 			   int silent)
5025 {
5026 	struct ext4_sb_info *sbi = EXT4_SB(sb);
5027 	struct ext4_super_block *es;
5028 	ext4_fsblk_t logical_sb_block;
5029 	unsigned long offset = 0;
5030 	struct buffer_head *bh;
5031 	int ret = -EINVAL;
5032 	int blocksize;
5033 
5034 	blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
5035 	if (!blocksize) {
5036 		ext4_msg(sb, KERN_ERR, "unable to set blocksize");
5037 		return -EINVAL;
5038 	}
5039 
5040 	/*
5041 	 * The ext4 superblock will not be buffer aligned for other than 1kB
5042 	 * block sizes.  We need to calculate the offset from buffer start.
5043 	 */
5044 	if (blocksize != EXT4_MIN_BLOCK_SIZE) {
5045 		logical_sb_block = sbi->s_sb_block * EXT4_MIN_BLOCK_SIZE;
5046 		offset = do_div(logical_sb_block, blocksize);
5047 	} else {
5048 		logical_sb_block = sbi->s_sb_block;
5049 	}
5050 
5051 	bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
5052 	if (IS_ERR(bh)) {
5053 		ext4_msg(sb, KERN_ERR, "unable to read superblock");
5054 		return PTR_ERR(bh);
5055 	}
5056 	/*
5057 	 * Note: s_es must be initialized as soon as possible because
5058 	 *       some ext4 macro-instructions depend on its value
5059 	 */
5060 	es = (struct ext4_super_block *) (bh->b_data + offset);
5061 	sbi->s_es = es;
5062 	sb->s_magic = le16_to_cpu(es->s_magic);
5063 	if (sb->s_magic != EXT4_SUPER_MAGIC) {
5064 		if (!silent)
5065 			ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
5066 		goto out;
5067 	}
5068 
5069 	if (le32_to_cpu(es->s_log_block_size) >
5070 	    (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
5071 		ext4_msg(sb, KERN_ERR,
5072 			 "Invalid log block size: %u",
5073 			 le32_to_cpu(es->s_log_block_size));
5074 		goto out;
5075 	}
5076 	if (le32_to_cpu(es->s_log_cluster_size) >
5077 	    (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
5078 		ext4_msg(sb, KERN_ERR,
5079 			 "Invalid log cluster size: %u",
5080 			 le32_to_cpu(es->s_log_cluster_size));
5081 		goto out;
5082 	}
5083 
5084 	blocksize = EXT4_MIN_BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
5085 
5086 	/*
5087 	 * If the default block size is not the same as the real block size,
5088 	 * we need to reload it.
5089 	 */
5090 	if (sb->s_blocksize == blocksize) {
5091 		*lsb = logical_sb_block;
5092 		sbi->s_sbh = bh;
5093 		return 0;
5094 	}
5095 
5096 	/*
5097 	 * bh must be released before kill_bdev(), otherwise
5098 	 * it won't be freed and its page also. kill_bdev()
5099 	 * is called by sb_set_blocksize().
5100 	 */
5101 	brelse(bh);
5102 	/* Validate the filesystem blocksize */
5103 	if (!sb_set_blocksize(sb, blocksize)) {
5104 		ext4_msg(sb, KERN_ERR, "bad block size %d",
5105 				blocksize);
5106 		bh = NULL;
5107 		goto out;
5108 	}
5109 
5110 	logical_sb_block = sbi->s_sb_block * EXT4_MIN_BLOCK_SIZE;
5111 	offset = do_div(logical_sb_block, blocksize);
5112 	bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
5113 	if (IS_ERR(bh)) {
5114 		ext4_msg(sb, KERN_ERR, "Can't read superblock on 2nd try");
5115 		ret = PTR_ERR(bh);
5116 		bh = NULL;
5117 		goto out;
5118 	}
5119 	es = (struct ext4_super_block *)(bh->b_data + offset);
5120 	sbi->s_es = es;
5121 	if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
5122 		ext4_msg(sb, KERN_ERR, "Magic mismatch, very weird!");
5123 		goto out;
5124 	}
5125 	*lsb = logical_sb_block;
5126 	sbi->s_sbh = bh;
5127 	return 0;
5128 out:
5129 	brelse(bh);
5130 	return ret;
5131 }
5132 
ext4_hash_info_init(struct super_block * sb)5133 static void ext4_hash_info_init(struct super_block *sb)
5134 {
5135 	struct ext4_sb_info *sbi = EXT4_SB(sb);
5136 	struct ext4_super_block *es = sbi->s_es;
5137 	unsigned int i;
5138 
5139 	for (i = 0; i < 4; i++)
5140 		sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
5141 
5142 	sbi->s_def_hash_version = es->s_def_hash_version;
5143 	if (ext4_has_feature_dir_index(sb)) {
5144 		i = le32_to_cpu(es->s_flags);
5145 		if (i & EXT2_FLAGS_UNSIGNED_HASH)
5146 			sbi->s_hash_unsigned = 3;
5147 		else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
5148 #ifdef __CHAR_UNSIGNED__
5149 			if (!sb_rdonly(sb))
5150 				es->s_flags |=
5151 					cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
5152 			sbi->s_hash_unsigned = 3;
5153 #else
5154 			if (!sb_rdonly(sb))
5155 				es->s_flags |=
5156 					cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
5157 #endif
5158 		}
5159 	}
5160 }
5161 
ext4_block_group_meta_init(struct super_block * sb,int silent)5162 static int ext4_block_group_meta_init(struct super_block *sb, int silent)
5163 {
5164 	struct ext4_sb_info *sbi = EXT4_SB(sb);
5165 	struct ext4_super_block *es = sbi->s_es;
5166 	int has_huge_files;
5167 
5168 	has_huge_files = ext4_has_feature_huge_file(sb);
5169 	sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
5170 						      has_huge_files);
5171 	sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
5172 
5173 	sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
5174 	if (ext4_has_feature_64bit(sb)) {
5175 		if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
5176 		    sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
5177 		    !is_power_of_2(sbi->s_desc_size)) {
5178 			ext4_msg(sb, KERN_ERR,
5179 			       "unsupported descriptor size %lu",
5180 			       sbi->s_desc_size);
5181 			return -EINVAL;
5182 		}
5183 	} else
5184 		sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
5185 
5186 	sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
5187 	sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
5188 
5189 	sbi->s_inodes_per_block = sb->s_blocksize / EXT4_INODE_SIZE(sb);
5190 	if (sbi->s_inodes_per_block == 0 || sbi->s_blocks_per_group == 0) {
5191 		if (!silent)
5192 			ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
5193 		return -EINVAL;
5194 	}
5195 	if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
5196 	    sbi->s_inodes_per_group > sb->s_blocksize * 8) {
5197 		ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
5198 			 sbi->s_inodes_per_group);
5199 		return -EINVAL;
5200 	}
5201 	sbi->s_itb_per_group = sbi->s_inodes_per_group /
5202 					sbi->s_inodes_per_block;
5203 	sbi->s_desc_per_block = sb->s_blocksize / EXT4_DESC_SIZE(sb);
5204 	sbi->s_mount_state = le16_to_cpu(es->s_state) & ~EXT4_FC_REPLAY;
5205 	sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
5206 	sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
5207 
5208 	return 0;
5209 }
5210 
__ext4_fill_super(struct fs_context * fc,struct super_block * sb)5211 static int __ext4_fill_super(struct fs_context *fc, struct super_block *sb)
5212 {
5213 	struct ext4_super_block *es = NULL;
5214 	struct ext4_sb_info *sbi = EXT4_SB(sb);
5215 	ext4_fsblk_t logical_sb_block;
5216 	struct inode *root;
5217 	int needs_recovery;
5218 	int err;
5219 	ext4_group_t first_not_zeroed;
5220 	struct ext4_fs_context *ctx = fc->fs_private;
5221 	int silent = fc->sb_flags & SB_SILENT;
5222 
5223 	/* Set defaults for the variables that will be set during parsing */
5224 	if (!(ctx->spec & EXT4_SPEC_JOURNAL_IOPRIO))
5225 		ctx->journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
5226 
5227 	sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
5228 	sbi->s_sectors_written_start =
5229 		part_stat_read(sb->s_bdev, sectors[STAT_WRITE]);
5230 
5231 	err = ext4_load_super(sb, &logical_sb_block, silent);
5232 	if (err)
5233 		goto out_fail;
5234 
5235 	es = sbi->s_es;
5236 	sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
5237 
5238 	err = ext4_init_metadata_csum(sb, es);
5239 	if (err)
5240 		goto failed_mount;
5241 
5242 	ext4_set_def_opts(sb, es);
5243 
5244 	sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
5245 	sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
5246 	sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
5247 	sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
5248 	sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
5249 
5250 	/*
5251 	 * set default s_li_wait_mult for lazyinit, for the case there is
5252 	 * no mount option specified.
5253 	 */
5254 	sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
5255 
5256 	err = ext4_inode_info_init(sb, es);
5257 	if (err)
5258 		goto failed_mount;
5259 
5260 	err = parse_apply_sb_mount_options(sb, ctx);
5261 	if (err < 0)
5262 		goto failed_mount;
5263 
5264 	sbi->s_def_mount_opt = sbi->s_mount_opt;
5265 	sbi->s_def_mount_opt2 = sbi->s_mount_opt2;
5266 
5267 	err = ext4_check_opt_consistency(fc, sb);
5268 	if (err < 0)
5269 		goto failed_mount;
5270 
5271 	ext4_apply_options(fc, sb);
5272 
5273 	err = ext4_encoding_init(sb, es);
5274 	if (err)
5275 		goto failed_mount;
5276 
5277 	err = ext4_check_journal_data_mode(sb);
5278 	if (err)
5279 		goto failed_mount;
5280 
5281 	sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
5282 		(test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
5283 
5284 	/* i_version is always enabled now */
5285 	sb->s_flags |= SB_I_VERSION;
5286 
5287 	err = ext4_check_feature_compatibility(sb, es, silent);
5288 	if (err)
5289 		goto failed_mount;
5290 
5291 	err = ext4_block_group_meta_init(sb, silent);
5292 	if (err)
5293 		goto failed_mount;
5294 
5295 	ext4_hash_info_init(sb);
5296 
5297 	err = ext4_handle_clustersize(sb);
5298 	if (err)
5299 		goto failed_mount;
5300 
5301 	err = ext4_check_geometry(sb, es);
5302 	if (err)
5303 		goto failed_mount;
5304 
5305 	timer_setup(&sbi->s_err_report, print_daily_error_info, 0);
5306 	spin_lock_init(&sbi->s_error_lock);
5307 	INIT_WORK(&sbi->s_sb_upd_work, update_super_work);
5308 
5309 	err = ext4_group_desc_init(sb, es, logical_sb_block, &first_not_zeroed);
5310 	if (err)
5311 		goto failed_mount3;
5312 
5313 	err = ext4_es_register_shrinker(sbi);
5314 	if (err)
5315 		goto failed_mount3;
5316 
5317 	sbi->s_stripe = ext4_get_stripe_size(sbi);
5318 	/*
5319 	 * It's hard to get stripe aligned blocks if stripe is not aligned with
5320 	 * cluster, just disable stripe and alert user to simpfy code and avoid
5321 	 * stripe aligned allocation which will rarely successes.
5322 	 */
5323 	if (sbi->s_stripe > 0 && sbi->s_cluster_ratio > 1 &&
5324 	    sbi->s_stripe % sbi->s_cluster_ratio != 0) {
5325 		ext4_msg(sb, KERN_WARNING,
5326 			 "stripe (%lu) is not aligned with cluster size (%u), "
5327 			 "stripe is disabled",
5328 			 sbi->s_stripe, sbi->s_cluster_ratio);
5329 		sbi->s_stripe = 0;
5330 	}
5331 	sbi->s_extent_max_zeroout_kb = 32;
5332 
5333 	/*
5334 	 * set up enough so that it can read an inode
5335 	 */
5336 	sb->s_op = &ext4_sops;
5337 	sb->s_export_op = &ext4_export_ops;
5338 	sb->s_xattr = ext4_xattr_handlers;
5339 #ifdef CONFIG_FS_ENCRYPTION
5340 	sb->s_cop = &ext4_cryptops;
5341 #endif
5342 #ifdef CONFIG_FS_VERITY
5343 	sb->s_vop = &ext4_verityops;
5344 #endif
5345 #ifdef CONFIG_QUOTA
5346 	sb->dq_op = &ext4_quota_operations;
5347 	if (ext4_has_feature_quota(sb))
5348 		sb->s_qcop = &dquot_quotactl_sysfile_ops;
5349 	else
5350 		sb->s_qcop = &ext4_qctl_operations;
5351 	sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
5352 #endif
5353 	memcpy(&sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
5354 
5355 	INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
5356 	mutex_init(&sbi->s_orphan_lock);
5357 
5358 	ext4_fast_commit_init(sb);
5359 
5360 	sb->s_root = NULL;
5361 
5362 	needs_recovery = (es->s_last_orphan != 0 ||
5363 			  ext4_has_feature_orphan_present(sb) ||
5364 			  ext4_has_feature_journal_needs_recovery(sb));
5365 
5366 	if (ext4_has_feature_mmp(sb) && !sb_rdonly(sb)) {
5367 		err = ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block));
5368 		if (err)
5369 			goto failed_mount3a;
5370 	}
5371 
5372 	err = -EINVAL;
5373 	/*
5374 	 * The first inode we look at is the journal inode.  Don't try
5375 	 * root first: it may be modified in the journal!
5376 	 */
5377 	if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
5378 		err = ext4_load_and_init_journal(sb, es, ctx);
5379 		if (err)
5380 			goto failed_mount3a;
5381 	} else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
5382 		   ext4_has_feature_journal_needs_recovery(sb)) {
5383 		ext4_msg(sb, KERN_ERR, "required journal recovery "
5384 		       "suppressed and not mounted read-only");
5385 		goto failed_mount3a;
5386 	} else {
5387 		/* Nojournal mode, all journal mount options are illegal */
5388 		if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5389 			ext4_msg(sb, KERN_ERR, "can't mount with "
5390 				 "journal_async_commit, fs mounted w/o journal");
5391 			goto failed_mount3a;
5392 		}
5393 
5394 		if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
5395 			ext4_msg(sb, KERN_ERR, "can't mount with "
5396 				 "journal_checksum, fs mounted w/o journal");
5397 			goto failed_mount3a;
5398 		}
5399 		if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
5400 			ext4_msg(sb, KERN_ERR, "can't mount with "
5401 				 "commit=%lu, fs mounted w/o journal",
5402 				 sbi->s_commit_interval / HZ);
5403 			goto failed_mount3a;
5404 		}
5405 		if (EXT4_MOUNT_DATA_FLAGS &
5406 		    (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
5407 			ext4_msg(sb, KERN_ERR, "can't mount with "
5408 				 "data=, fs mounted w/o journal");
5409 			goto failed_mount3a;
5410 		}
5411 		sbi->s_def_mount_opt &= ~EXT4_MOUNT_JOURNAL_CHECKSUM;
5412 		clear_opt(sb, JOURNAL_CHECKSUM);
5413 		clear_opt(sb, DATA_FLAGS);
5414 		clear_opt2(sb, JOURNAL_FAST_COMMIT);
5415 		sbi->s_journal = NULL;
5416 		needs_recovery = 0;
5417 	}
5418 
5419 	if (!test_opt(sb, NO_MBCACHE)) {
5420 		sbi->s_ea_block_cache = ext4_xattr_create_cache();
5421 		if (!sbi->s_ea_block_cache) {
5422 			ext4_msg(sb, KERN_ERR,
5423 				 "Failed to create ea_block_cache");
5424 			err = -EINVAL;
5425 			goto failed_mount_wq;
5426 		}
5427 
5428 		if (ext4_has_feature_ea_inode(sb)) {
5429 			sbi->s_ea_inode_cache = ext4_xattr_create_cache();
5430 			if (!sbi->s_ea_inode_cache) {
5431 				ext4_msg(sb, KERN_ERR,
5432 					 "Failed to create ea_inode_cache");
5433 				err = -EINVAL;
5434 				goto failed_mount_wq;
5435 			}
5436 		}
5437 	}
5438 
5439 	/*
5440 	 * Get the # of file system overhead blocks from the
5441 	 * superblock if present.
5442 	 */
5443 	sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
5444 	/* ignore the precalculated value if it is ridiculous */
5445 	if (sbi->s_overhead > ext4_blocks_count(es))
5446 		sbi->s_overhead = 0;
5447 	/*
5448 	 * If the bigalloc feature is not enabled recalculating the
5449 	 * overhead doesn't take long, so we might as well just redo
5450 	 * it to make sure we are using the correct value.
5451 	 */
5452 	if (!ext4_has_feature_bigalloc(sb))
5453 		sbi->s_overhead = 0;
5454 	if (sbi->s_overhead == 0) {
5455 		err = ext4_calculate_overhead(sb);
5456 		if (err)
5457 			goto failed_mount_wq;
5458 	}
5459 
5460 	/*
5461 	 * The maximum number of concurrent works can be high and
5462 	 * concurrency isn't really necessary.  Limit it to 1.
5463 	 */
5464 	EXT4_SB(sb)->rsv_conversion_wq =
5465 		alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
5466 	if (!EXT4_SB(sb)->rsv_conversion_wq) {
5467 		printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
5468 		err = -ENOMEM;
5469 		goto failed_mount4;
5470 	}
5471 
5472 	/*
5473 	 * The jbd2_journal_load will have done any necessary log recovery,
5474 	 * so we can safely mount the rest of the filesystem now.
5475 	 */
5476 
5477 	root = ext4_iget(sb, EXT4_ROOT_INO, EXT4_IGET_SPECIAL);
5478 	if (IS_ERR(root)) {
5479 		ext4_msg(sb, KERN_ERR, "get root inode failed");
5480 		err = PTR_ERR(root);
5481 		root = NULL;
5482 		goto failed_mount4;
5483 	}
5484 	if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
5485 		ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
5486 		iput(root);
5487 		err = -EFSCORRUPTED;
5488 		goto failed_mount4;
5489 	}
5490 
5491 	sb->s_root = d_make_root(root);
5492 	if (!sb->s_root) {
5493 		ext4_msg(sb, KERN_ERR, "get root dentry failed");
5494 		err = -ENOMEM;
5495 		goto failed_mount4;
5496 	}
5497 
5498 	err = ext4_setup_super(sb, es, sb_rdonly(sb));
5499 	if (err == -EROFS) {
5500 		sb->s_flags |= SB_RDONLY;
5501 	} else if (err)
5502 		goto failed_mount4a;
5503 
5504 	ext4_set_resv_clusters(sb);
5505 
5506 	if (test_opt(sb, BLOCK_VALIDITY)) {
5507 		err = ext4_setup_system_zone(sb);
5508 		if (err) {
5509 			ext4_msg(sb, KERN_ERR, "failed to initialize system "
5510 				 "zone (%d)", err);
5511 			goto failed_mount4a;
5512 		}
5513 	}
5514 	ext4_fc_replay_cleanup(sb);
5515 
5516 	ext4_ext_init(sb);
5517 
5518 	/*
5519 	 * Enable optimize_scan if number of groups is > threshold. This can be
5520 	 * turned off by passing "mb_optimize_scan=0". This can also be
5521 	 * turned on forcefully by passing "mb_optimize_scan=1".
5522 	 */
5523 	if (!(ctx->spec & EXT4_SPEC_mb_optimize_scan)) {
5524 		if (sbi->s_groups_count >= MB_DEFAULT_LINEAR_SCAN_THRESHOLD)
5525 			set_opt2(sb, MB_OPTIMIZE_SCAN);
5526 		else
5527 			clear_opt2(sb, MB_OPTIMIZE_SCAN);
5528 	}
5529 
5530 	err = ext4_mb_init(sb);
5531 	if (err) {
5532 		ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
5533 			 err);
5534 		goto failed_mount5;
5535 	}
5536 
5537 	/*
5538 	 * We can only set up the journal commit callback once
5539 	 * mballoc is initialized
5540 	 */
5541 	if (sbi->s_journal)
5542 		sbi->s_journal->j_commit_callback =
5543 			ext4_journal_commit_callback;
5544 
5545 	err = ext4_percpu_param_init(sbi);
5546 	if (err)
5547 		goto failed_mount6;
5548 
5549 	if (ext4_has_feature_flex_bg(sb))
5550 		if (!ext4_fill_flex_info(sb)) {
5551 			ext4_msg(sb, KERN_ERR,
5552 			       "unable to initialize "
5553 			       "flex_bg meta info!");
5554 			err = -ENOMEM;
5555 			goto failed_mount6;
5556 		}
5557 
5558 	err = ext4_register_li_request(sb, first_not_zeroed);
5559 	if (err)
5560 		goto failed_mount6;
5561 
5562 	err = ext4_init_orphan_info(sb);
5563 	if (err)
5564 		goto failed_mount7;
5565 #ifdef CONFIG_QUOTA
5566 	/* Enable quota usage during mount. */
5567 	if (ext4_has_feature_quota(sb) && !sb_rdonly(sb)) {
5568 		err = ext4_enable_quotas(sb);
5569 		if (err)
5570 			goto failed_mount8;
5571 	}
5572 #endif  /* CONFIG_QUOTA */
5573 
5574 	/*
5575 	 * Save the original bdev mapping's wb_err value which could be
5576 	 * used to detect the metadata async write error.
5577 	 */
5578 	spin_lock_init(&sbi->s_bdev_wb_lock);
5579 	errseq_check_and_advance(&sb->s_bdev->bd_inode->i_mapping->wb_err,
5580 				 &sbi->s_bdev_wb_err);
5581 	EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
5582 	ext4_orphan_cleanup(sb, es);
5583 	EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
5584 	/*
5585 	 * Update the checksum after updating free space/inode counters and
5586 	 * ext4_orphan_cleanup. Otherwise the superblock can have an incorrect
5587 	 * checksum in the buffer cache until it is written out and
5588 	 * e2fsprogs programs trying to open a file system immediately
5589 	 * after it is mounted can fail.
5590 	 */
5591 	ext4_superblock_csum_set(sb);
5592 	if (needs_recovery) {
5593 		ext4_msg(sb, KERN_INFO, "recovery complete");
5594 		err = ext4_mark_recovery_complete(sb, es);
5595 		if (err)
5596 			goto failed_mount9;
5597 	}
5598 
5599 	if (test_opt(sb, DISCARD) && !bdev_max_discard_sectors(sb->s_bdev))
5600 		ext4_msg(sb, KERN_WARNING,
5601 			 "mounting with \"discard\" option, but the device does not support discard");
5602 
5603 	if (es->s_error_count)
5604 		mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
5605 
5606 	/* Enable message ratelimiting. Default is 10 messages per 5 secs. */
5607 	ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
5608 	ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
5609 	ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
5610 	atomic_set(&sbi->s_warning_count, 0);
5611 	atomic_set(&sbi->s_msg_count, 0);
5612 
5613 	/* Register sysfs after all initializations are complete. */
5614 	err = ext4_register_sysfs(sb);
5615 	if (err)
5616 		goto failed_mount9;
5617 
5618 	return 0;
5619 
5620 failed_mount9:
5621 	ext4_quotas_off(sb, EXT4_MAXQUOTAS);
5622 failed_mount8: __maybe_unused
5623 	ext4_release_orphan_info(sb);
5624 failed_mount7:
5625 	ext4_unregister_li_request(sb);
5626 failed_mount6:
5627 	ext4_mb_release(sb);
5628 	ext4_flex_groups_free(sbi);
5629 	ext4_percpu_param_destroy(sbi);
5630 failed_mount5:
5631 	ext4_ext_release(sb);
5632 	ext4_release_system_zone(sb);
5633 failed_mount4a:
5634 	dput(sb->s_root);
5635 	sb->s_root = NULL;
5636 failed_mount4:
5637 	ext4_msg(sb, KERN_ERR, "mount failed");
5638 	if (EXT4_SB(sb)->rsv_conversion_wq)
5639 		destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
5640 failed_mount_wq:
5641 	ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
5642 	sbi->s_ea_inode_cache = NULL;
5643 
5644 	ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
5645 	sbi->s_ea_block_cache = NULL;
5646 
5647 	if (sbi->s_journal) {
5648 		/* flush s_sb_upd_work before journal destroy. */
5649 		flush_work(&sbi->s_sb_upd_work);
5650 		jbd2_journal_destroy(sbi->s_journal);
5651 		sbi->s_journal = NULL;
5652 	}
5653 failed_mount3a:
5654 	ext4_es_unregister_shrinker(sbi);
5655 failed_mount3:
5656 	/* flush s_sb_upd_work before sbi destroy */
5657 	flush_work(&sbi->s_sb_upd_work);
5658 	del_timer_sync(&sbi->s_err_report);
5659 	ext4_stop_mmpd(sbi);
5660 	ext4_group_desc_free(sbi);
5661 failed_mount:
5662 	if (sbi->s_chksum_driver)
5663 		crypto_free_shash(sbi->s_chksum_driver);
5664 
5665 #if IS_ENABLED(CONFIG_UNICODE)
5666 	utf8_unload(sb->s_encoding);
5667 #endif
5668 
5669 #ifdef CONFIG_QUOTA
5670 	for (unsigned int i = 0; i < EXT4_MAXQUOTAS; i++)
5671 		kfree(get_qf_name(sb, sbi, i));
5672 #endif
5673 	fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy);
5674 	brelse(sbi->s_sbh);
5675 	if (sbi->s_journal_bdev) {
5676 		invalidate_bdev(sbi->s_journal_bdev);
5677 		blkdev_put(sbi->s_journal_bdev, sb);
5678 	}
5679 out_fail:
5680 	invalidate_bdev(sb->s_bdev);
5681 	sb->s_fs_info = NULL;
5682 	return err;
5683 }
5684 
ext4_fill_super(struct super_block * sb,struct fs_context * fc)5685 static int ext4_fill_super(struct super_block *sb, struct fs_context *fc)
5686 {
5687 	struct ext4_fs_context *ctx = fc->fs_private;
5688 	struct ext4_sb_info *sbi;
5689 	const char *descr;
5690 	int ret;
5691 
5692 	sbi = ext4_alloc_sbi(sb);
5693 	if (!sbi)
5694 		return -ENOMEM;
5695 
5696 	fc->s_fs_info = sbi;
5697 
5698 	/* Cleanup superblock name */
5699 	strreplace(sb->s_id, '/', '!');
5700 
5701 	sbi->s_sb_block = 1;	/* Default super block location */
5702 	if (ctx->spec & EXT4_SPEC_s_sb_block)
5703 		sbi->s_sb_block = ctx->s_sb_block;
5704 
5705 	ret = __ext4_fill_super(fc, sb);
5706 	if (ret < 0)
5707 		goto free_sbi;
5708 
5709 	if (sbi->s_journal) {
5710 		if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
5711 			descr = " journalled data mode";
5712 		else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
5713 			descr = " ordered data mode";
5714 		else
5715 			descr = " writeback data mode";
5716 	} else
5717 		descr = "out journal";
5718 
5719 	if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
5720 		ext4_msg(sb, KERN_INFO, "mounted filesystem %pU %s with%s. "
5721 			 "Quota mode: %s.", &sb->s_uuid,
5722 			 sb_rdonly(sb) ? "ro" : "r/w", descr,
5723 			 ext4_quota_mode(sb));
5724 
5725 	/* Update the s_overhead_clusters if necessary */
5726 	ext4_update_overhead(sb, false);
5727 	return 0;
5728 
5729 free_sbi:
5730 	ext4_free_sbi(sbi);
5731 	fc->s_fs_info = NULL;
5732 	return ret;
5733 }
5734 
ext4_get_tree(struct fs_context * fc)5735 static int ext4_get_tree(struct fs_context *fc)
5736 {
5737 	return get_tree_bdev(fc, ext4_fill_super);
5738 }
5739 
5740 /*
5741  * Setup any per-fs journal parameters now.  We'll do this both on
5742  * initial mount, once the journal has been initialised but before we've
5743  * done any recovery; and again on any subsequent remount.
5744  */
ext4_init_journal_params(struct super_block * sb,journal_t * journal)5745 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
5746 {
5747 	struct ext4_sb_info *sbi = EXT4_SB(sb);
5748 
5749 	journal->j_commit_interval = sbi->s_commit_interval;
5750 	journal->j_min_batch_time = sbi->s_min_batch_time;
5751 	journal->j_max_batch_time = sbi->s_max_batch_time;
5752 	ext4_fc_init(sb, journal);
5753 
5754 	write_lock(&journal->j_state_lock);
5755 	if (test_opt(sb, BARRIER))
5756 		journal->j_flags |= JBD2_BARRIER;
5757 	else
5758 		journal->j_flags &= ~JBD2_BARRIER;
5759 	if (test_opt(sb, DATA_ERR_ABORT))
5760 		journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
5761 	else
5762 		journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
5763 	/*
5764 	 * Always enable journal cycle record option, letting the journal
5765 	 * records log transactions continuously between each mount.
5766 	 */
5767 	journal->j_flags |= JBD2_CYCLE_RECORD;
5768 	write_unlock(&journal->j_state_lock);
5769 }
5770 
ext4_get_journal_inode(struct super_block * sb,unsigned int journal_inum)5771 static struct inode *ext4_get_journal_inode(struct super_block *sb,
5772 					     unsigned int journal_inum)
5773 {
5774 	struct inode *journal_inode;
5775 
5776 	/*
5777 	 * Test for the existence of a valid inode on disk.  Bad things
5778 	 * happen if we iget() an unused inode, as the subsequent iput()
5779 	 * will try to delete it.
5780 	 */
5781 	journal_inode = ext4_iget(sb, journal_inum, EXT4_IGET_SPECIAL);
5782 	if (IS_ERR(journal_inode)) {
5783 		ext4_msg(sb, KERN_ERR, "no journal found");
5784 		return ERR_CAST(journal_inode);
5785 	}
5786 	if (!journal_inode->i_nlink) {
5787 		make_bad_inode(journal_inode);
5788 		iput(journal_inode);
5789 		ext4_msg(sb, KERN_ERR, "journal inode is deleted");
5790 		return ERR_PTR(-EFSCORRUPTED);
5791 	}
5792 	if (!S_ISREG(journal_inode->i_mode) || IS_ENCRYPTED(journal_inode)) {
5793 		ext4_msg(sb, KERN_ERR, "invalid journal inode");
5794 		iput(journal_inode);
5795 		return ERR_PTR(-EFSCORRUPTED);
5796 	}
5797 
5798 	ext4_debug("Journal inode found at %p: %lld bytes\n",
5799 		  journal_inode, journal_inode->i_size);
5800 	return journal_inode;
5801 }
5802 
ext4_journal_bmap(journal_t * journal,sector_t * block)5803 static int ext4_journal_bmap(journal_t *journal, sector_t *block)
5804 {
5805 	struct ext4_map_blocks map;
5806 	int ret;
5807 
5808 	if (journal->j_inode == NULL)
5809 		return 0;
5810 
5811 	map.m_lblk = *block;
5812 	map.m_len = 1;
5813 	ret = ext4_map_blocks(NULL, journal->j_inode, &map, 0);
5814 	if (ret <= 0) {
5815 		ext4_msg(journal->j_inode->i_sb, KERN_CRIT,
5816 			 "journal bmap failed: block %llu ret %d\n",
5817 			 *block, ret);
5818 		jbd2_journal_abort(journal, ret ? ret : -EIO);
5819 		return ret;
5820 	}
5821 	*block = map.m_pblk;
5822 	return 0;
5823 }
5824 
ext4_open_inode_journal(struct super_block * sb,unsigned int journal_inum)5825 static journal_t *ext4_open_inode_journal(struct super_block *sb,
5826 					  unsigned int journal_inum)
5827 {
5828 	struct inode *journal_inode;
5829 	journal_t *journal;
5830 
5831 	journal_inode = ext4_get_journal_inode(sb, journal_inum);
5832 	if (IS_ERR(journal_inode))
5833 		return ERR_CAST(journal_inode);
5834 
5835 	journal = jbd2_journal_init_inode(journal_inode);
5836 	if (IS_ERR(journal)) {
5837 		ext4_msg(sb, KERN_ERR, "Could not load journal inode");
5838 		iput(journal_inode);
5839 		return ERR_CAST(journal);
5840 	}
5841 	journal->j_private = sb;
5842 	journal->j_bmap = ext4_journal_bmap;
5843 	ext4_init_journal_params(sb, journal);
5844 	return journal;
5845 }
5846 
ext4_get_journal_blkdev(struct super_block * sb,dev_t j_dev,ext4_fsblk_t * j_start,ext4_fsblk_t * j_len)5847 static struct block_device *ext4_get_journal_blkdev(struct super_block *sb,
5848 					dev_t j_dev, ext4_fsblk_t *j_start,
5849 					ext4_fsblk_t *j_len)
5850 {
5851 	struct buffer_head *bh;
5852 	struct block_device *bdev;
5853 	int hblock, blocksize;
5854 	ext4_fsblk_t sb_block;
5855 	unsigned long offset;
5856 	struct ext4_super_block *es;
5857 	int errno;
5858 
5859 	/* see get_tree_bdev why this is needed and safe */
5860 	up_write(&sb->s_umount);
5861 	bdev = blkdev_get_by_dev(j_dev, BLK_OPEN_READ | BLK_OPEN_WRITE, sb,
5862 				 &fs_holder_ops);
5863 	down_write(&sb->s_umount);
5864 	if (IS_ERR(bdev)) {
5865 		ext4_msg(sb, KERN_ERR,
5866 			 "failed to open journal device unknown-block(%u,%u) %ld",
5867 			 MAJOR(j_dev), MINOR(j_dev), PTR_ERR(bdev));
5868 		return ERR_CAST(bdev);
5869 	}
5870 
5871 	blocksize = sb->s_blocksize;
5872 	hblock = bdev_logical_block_size(bdev);
5873 	if (blocksize < hblock) {
5874 		ext4_msg(sb, KERN_ERR,
5875 			"blocksize too small for journal device");
5876 		errno = -EINVAL;
5877 		goto out_bdev;
5878 	}
5879 
5880 	sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
5881 	offset = EXT4_MIN_BLOCK_SIZE % blocksize;
5882 	set_blocksize(bdev, blocksize);
5883 	bh = __bread(bdev, sb_block, blocksize);
5884 	if (!bh) {
5885 		ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
5886 		       "external journal");
5887 		errno = -EINVAL;
5888 		goto out_bdev;
5889 	}
5890 
5891 	es = (struct ext4_super_block *) (bh->b_data + offset);
5892 	if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
5893 	    !(le32_to_cpu(es->s_feature_incompat) &
5894 	      EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
5895 		ext4_msg(sb, KERN_ERR, "external journal has bad superblock");
5896 		errno = -EFSCORRUPTED;
5897 		goto out_bh;
5898 	}
5899 
5900 	if ((le32_to_cpu(es->s_feature_ro_compat) &
5901 	     EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
5902 	    es->s_checksum != ext4_superblock_csum(sb, es)) {
5903 		ext4_msg(sb, KERN_ERR, "external journal has corrupt superblock");
5904 		errno = -EFSCORRUPTED;
5905 		goto out_bh;
5906 	}
5907 
5908 	if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
5909 		ext4_msg(sb, KERN_ERR, "journal UUID does not match");
5910 		errno = -EFSCORRUPTED;
5911 		goto out_bh;
5912 	}
5913 
5914 	*j_start = sb_block + 1;
5915 	*j_len = ext4_blocks_count(es);
5916 	brelse(bh);
5917 	return bdev;
5918 
5919 out_bh:
5920 	brelse(bh);
5921 out_bdev:
5922 	blkdev_put(bdev, sb);
5923 	return ERR_PTR(errno);
5924 }
5925 
ext4_open_dev_journal(struct super_block * sb,dev_t j_dev)5926 static journal_t *ext4_open_dev_journal(struct super_block *sb,
5927 					dev_t j_dev)
5928 {
5929 	journal_t *journal;
5930 	ext4_fsblk_t j_start;
5931 	ext4_fsblk_t j_len;
5932 	struct block_device *journal_bdev;
5933 	int errno = 0;
5934 
5935 	journal_bdev = ext4_get_journal_blkdev(sb, j_dev, &j_start, &j_len);
5936 	if (IS_ERR(journal_bdev))
5937 		return ERR_CAST(journal_bdev);
5938 
5939 	journal = jbd2_journal_init_dev(journal_bdev, sb->s_bdev, j_start,
5940 					j_len, sb->s_blocksize);
5941 	if (IS_ERR(journal)) {
5942 		ext4_msg(sb, KERN_ERR, "failed to create device journal");
5943 		errno = PTR_ERR(journal);
5944 		goto out_bdev;
5945 	}
5946 	if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
5947 		ext4_msg(sb, KERN_ERR, "External journal has more than one "
5948 					"user (unsupported) - %d",
5949 			be32_to_cpu(journal->j_superblock->s_nr_users));
5950 		errno = -EINVAL;
5951 		goto out_journal;
5952 	}
5953 	journal->j_private = sb;
5954 	EXT4_SB(sb)->s_journal_bdev = journal_bdev;
5955 	ext4_init_journal_params(sb, journal);
5956 	return journal;
5957 
5958 out_journal:
5959 	jbd2_journal_destroy(journal);
5960 out_bdev:
5961 	blkdev_put(journal_bdev, sb);
5962 	return ERR_PTR(errno);
5963 }
5964 
ext4_load_journal(struct super_block * sb,struct ext4_super_block * es,unsigned long journal_devnum)5965 static int ext4_load_journal(struct super_block *sb,
5966 			     struct ext4_super_block *es,
5967 			     unsigned long journal_devnum)
5968 {
5969 	journal_t *journal;
5970 	unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
5971 	dev_t journal_dev;
5972 	int err = 0;
5973 	int really_read_only;
5974 	int journal_dev_ro;
5975 
5976 	if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5977 		return -EFSCORRUPTED;
5978 
5979 	if (journal_devnum &&
5980 	    journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5981 		ext4_msg(sb, KERN_INFO, "external journal device major/minor "
5982 			"numbers have changed");
5983 		journal_dev = new_decode_dev(journal_devnum);
5984 	} else
5985 		journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
5986 
5987 	if (journal_inum && journal_dev) {
5988 		ext4_msg(sb, KERN_ERR,
5989 			 "filesystem has both journal inode and journal device!");
5990 		return -EINVAL;
5991 	}
5992 
5993 	if (journal_inum) {
5994 		journal = ext4_open_inode_journal(sb, journal_inum);
5995 		if (IS_ERR(journal))
5996 			return PTR_ERR(journal);
5997 	} else {
5998 		journal = ext4_open_dev_journal(sb, journal_dev);
5999 		if (IS_ERR(journal))
6000 			return PTR_ERR(journal);
6001 	}
6002 
6003 	journal_dev_ro = bdev_read_only(journal->j_dev);
6004 	really_read_only = bdev_read_only(sb->s_bdev) | journal_dev_ro;
6005 
6006 	if (journal_dev_ro && !sb_rdonly(sb)) {
6007 		ext4_msg(sb, KERN_ERR,
6008 			 "journal device read-only, try mounting with '-o ro'");
6009 		err = -EROFS;
6010 		goto err_out;
6011 	}
6012 
6013 	/*
6014 	 * Are we loading a blank journal or performing recovery after a
6015 	 * crash?  For recovery, we need to check in advance whether we
6016 	 * can get read-write access to the device.
6017 	 */
6018 	if (ext4_has_feature_journal_needs_recovery(sb)) {
6019 		if (sb_rdonly(sb)) {
6020 			ext4_msg(sb, KERN_INFO, "INFO: recovery "
6021 					"required on readonly filesystem");
6022 			if (really_read_only) {
6023 				ext4_msg(sb, KERN_ERR, "write access "
6024 					"unavailable, cannot proceed "
6025 					"(try mounting with noload)");
6026 				err = -EROFS;
6027 				goto err_out;
6028 			}
6029 			ext4_msg(sb, KERN_INFO, "write access will "
6030 			       "be enabled during recovery");
6031 		}
6032 	}
6033 
6034 	if (!(journal->j_flags & JBD2_BARRIER))
6035 		ext4_msg(sb, KERN_INFO, "barriers disabled");
6036 
6037 	if (!ext4_has_feature_journal_needs_recovery(sb))
6038 		err = jbd2_journal_wipe(journal, !really_read_only);
6039 	if (!err) {
6040 		char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
6041 		__le16 orig_state;
6042 		bool changed = false;
6043 
6044 		if (save)
6045 			memcpy(save, ((char *) es) +
6046 			       EXT4_S_ERR_START, EXT4_S_ERR_LEN);
6047 		err = jbd2_journal_load(journal);
6048 		if (save && memcmp(((char *) es) + EXT4_S_ERR_START,
6049 				   save, EXT4_S_ERR_LEN)) {
6050 			memcpy(((char *) es) + EXT4_S_ERR_START,
6051 			       save, EXT4_S_ERR_LEN);
6052 			changed = true;
6053 		}
6054 		kfree(save);
6055 		orig_state = es->s_state;
6056 		es->s_state |= cpu_to_le16(EXT4_SB(sb)->s_mount_state &
6057 					   EXT4_ERROR_FS);
6058 		if (orig_state != es->s_state)
6059 			changed = true;
6060 		/* Write out restored error information to the superblock */
6061 		if (changed && !really_read_only) {
6062 			int err2;
6063 			err2 = ext4_commit_super(sb);
6064 			err = err ? : err2;
6065 		}
6066 	}
6067 
6068 	if (err) {
6069 		ext4_msg(sb, KERN_ERR, "error loading journal");
6070 		goto err_out;
6071 	}
6072 
6073 	EXT4_SB(sb)->s_journal = journal;
6074 	err = ext4_clear_journal_err(sb, es);
6075 	if (err) {
6076 		EXT4_SB(sb)->s_journal = NULL;
6077 		jbd2_journal_destroy(journal);
6078 		return err;
6079 	}
6080 
6081 	if (!really_read_only && journal_devnum &&
6082 	    journal_devnum != le32_to_cpu(es->s_journal_dev)) {
6083 		es->s_journal_dev = cpu_to_le32(journal_devnum);
6084 		ext4_commit_super(sb);
6085 	}
6086 	if (!really_read_only && journal_inum &&
6087 	    journal_inum != le32_to_cpu(es->s_journal_inum)) {
6088 		es->s_journal_inum = cpu_to_le32(journal_inum);
6089 		ext4_commit_super(sb);
6090 	}
6091 
6092 	return 0;
6093 
6094 err_out:
6095 	jbd2_journal_destroy(journal);
6096 	return err;
6097 }
6098 
6099 /* Copy state of EXT4_SB(sb) into buffer for on-disk superblock */
ext4_update_super(struct super_block * sb)6100 static void ext4_update_super(struct super_block *sb)
6101 {
6102 	struct ext4_sb_info *sbi = EXT4_SB(sb);
6103 	struct ext4_super_block *es = sbi->s_es;
6104 	struct buffer_head *sbh = sbi->s_sbh;
6105 
6106 	lock_buffer(sbh);
6107 	/*
6108 	 * If the file system is mounted read-only, don't update the
6109 	 * superblock write time.  This avoids updating the superblock
6110 	 * write time when we are mounting the root file system
6111 	 * read/only but we need to replay the journal; at that point,
6112 	 * for people who are east of GMT and who make their clock
6113 	 * tick in localtime for Windows bug-for-bug compatibility,
6114 	 * the clock is set in the future, and this will cause e2fsck
6115 	 * to complain and force a full file system check.
6116 	 */
6117 	if (!sb_rdonly(sb))
6118 		ext4_update_tstamp(es, s_wtime);
6119 	es->s_kbytes_written =
6120 		cpu_to_le64(sbi->s_kbytes_written +
6121 		    ((part_stat_read(sb->s_bdev, sectors[STAT_WRITE]) -
6122 		      sbi->s_sectors_written_start) >> 1));
6123 	if (percpu_counter_initialized(&sbi->s_freeclusters_counter))
6124 		ext4_free_blocks_count_set(es,
6125 			EXT4_C2B(sbi, percpu_counter_sum_positive(
6126 				&sbi->s_freeclusters_counter)));
6127 	if (percpu_counter_initialized(&sbi->s_freeinodes_counter))
6128 		es->s_free_inodes_count =
6129 			cpu_to_le32(percpu_counter_sum_positive(
6130 				&sbi->s_freeinodes_counter));
6131 	/* Copy error information to the on-disk superblock */
6132 	spin_lock(&sbi->s_error_lock);
6133 	if (sbi->s_add_error_count > 0) {
6134 		es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
6135 		if (!es->s_first_error_time && !es->s_first_error_time_hi) {
6136 			__ext4_update_tstamp(&es->s_first_error_time,
6137 					     &es->s_first_error_time_hi,
6138 					     sbi->s_first_error_time);
6139 			strncpy(es->s_first_error_func, sbi->s_first_error_func,
6140 				sizeof(es->s_first_error_func));
6141 			es->s_first_error_line =
6142 				cpu_to_le32(sbi->s_first_error_line);
6143 			es->s_first_error_ino =
6144 				cpu_to_le32(sbi->s_first_error_ino);
6145 			es->s_first_error_block =
6146 				cpu_to_le64(sbi->s_first_error_block);
6147 			es->s_first_error_errcode =
6148 				ext4_errno_to_code(sbi->s_first_error_code);
6149 		}
6150 		__ext4_update_tstamp(&es->s_last_error_time,
6151 				     &es->s_last_error_time_hi,
6152 				     sbi->s_last_error_time);
6153 		strncpy(es->s_last_error_func, sbi->s_last_error_func,
6154 			sizeof(es->s_last_error_func));
6155 		es->s_last_error_line = cpu_to_le32(sbi->s_last_error_line);
6156 		es->s_last_error_ino = cpu_to_le32(sbi->s_last_error_ino);
6157 		es->s_last_error_block = cpu_to_le64(sbi->s_last_error_block);
6158 		es->s_last_error_errcode =
6159 				ext4_errno_to_code(sbi->s_last_error_code);
6160 		/*
6161 		 * Start the daily error reporting function if it hasn't been
6162 		 * started already
6163 		 */
6164 		if (!es->s_error_count)
6165 			mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);
6166 		le32_add_cpu(&es->s_error_count, sbi->s_add_error_count);
6167 		sbi->s_add_error_count = 0;
6168 	}
6169 	spin_unlock(&sbi->s_error_lock);
6170 
6171 	ext4_superblock_csum_set(sb);
6172 	unlock_buffer(sbh);
6173 }
6174 
ext4_commit_super(struct super_block * sb)6175 static int ext4_commit_super(struct super_block *sb)
6176 {
6177 	struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
6178 
6179 	if (!sbh)
6180 		return -EINVAL;
6181 	if (block_device_ejected(sb))
6182 		return -ENODEV;
6183 
6184 	ext4_update_super(sb);
6185 
6186 	lock_buffer(sbh);
6187 	/* Buffer got discarded which means block device got invalidated */
6188 	if (!buffer_mapped(sbh)) {
6189 		unlock_buffer(sbh);
6190 		return -EIO;
6191 	}
6192 
6193 	if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
6194 		/*
6195 		 * Oh, dear.  A previous attempt to write the
6196 		 * superblock failed.  This could happen because the
6197 		 * USB device was yanked out.  Or it could happen to
6198 		 * be a transient write error and maybe the block will
6199 		 * be remapped.  Nothing we can do but to retry the
6200 		 * write and hope for the best.
6201 		 */
6202 		ext4_msg(sb, KERN_ERR, "previous I/O error to "
6203 		       "superblock detected");
6204 		clear_buffer_write_io_error(sbh);
6205 		set_buffer_uptodate(sbh);
6206 	}
6207 	get_bh(sbh);
6208 	/* Clear potential dirty bit if it was journalled update */
6209 	clear_buffer_dirty(sbh);
6210 	sbh->b_end_io = end_buffer_write_sync;
6211 	submit_bh(REQ_OP_WRITE | REQ_SYNC |
6212 		  (test_opt(sb, BARRIER) ? REQ_FUA : 0), sbh);
6213 	wait_on_buffer(sbh);
6214 	if (buffer_write_io_error(sbh)) {
6215 		ext4_msg(sb, KERN_ERR, "I/O error while writing "
6216 		       "superblock");
6217 		clear_buffer_write_io_error(sbh);
6218 		set_buffer_uptodate(sbh);
6219 		return -EIO;
6220 	}
6221 	return 0;
6222 }
6223 
6224 /*
6225  * Have we just finished recovery?  If so, and if we are mounting (or
6226  * remounting) the filesystem readonly, then we will end up with a
6227  * consistent fs on disk.  Record that fact.
6228  */
ext4_mark_recovery_complete(struct super_block * sb,struct ext4_super_block * es)6229 static int ext4_mark_recovery_complete(struct super_block *sb,
6230 				       struct ext4_super_block *es)
6231 {
6232 	int err;
6233 	journal_t *journal = EXT4_SB(sb)->s_journal;
6234 
6235 	if (!ext4_has_feature_journal(sb)) {
6236 		if (journal != NULL) {
6237 			ext4_error(sb, "Journal got removed while the fs was "
6238 				   "mounted!");
6239 			return -EFSCORRUPTED;
6240 		}
6241 		return 0;
6242 	}
6243 	jbd2_journal_lock_updates(journal);
6244 	err = jbd2_journal_flush(journal, 0);
6245 	if (err < 0)
6246 		goto out;
6247 
6248 	if (sb_rdonly(sb) && (ext4_has_feature_journal_needs_recovery(sb) ||
6249 	    ext4_has_feature_orphan_present(sb))) {
6250 		if (!ext4_orphan_file_empty(sb)) {
6251 			ext4_error(sb, "Orphan file not empty on read-only fs.");
6252 			err = -EFSCORRUPTED;
6253 			goto out;
6254 		}
6255 		ext4_clear_feature_journal_needs_recovery(sb);
6256 		ext4_clear_feature_orphan_present(sb);
6257 		ext4_commit_super(sb);
6258 	}
6259 out:
6260 	jbd2_journal_unlock_updates(journal);
6261 	return err;
6262 }
6263 
6264 /*
6265  * If we are mounting (or read-write remounting) a filesystem whose journal
6266  * has recorded an error from a previous lifetime, move that error to the
6267  * main filesystem now.
6268  */
ext4_clear_journal_err(struct super_block * sb,struct ext4_super_block * es)6269 static int ext4_clear_journal_err(struct super_block *sb,
6270 				   struct ext4_super_block *es)
6271 {
6272 	journal_t *journal;
6273 	int j_errno;
6274 	const char *errstr;
6275 
6276 	if (!ext4_has_feature_journal(sb)) {
6277 		ext4_error(sb, "Journal got removed while the fs was mounted!");
6278 		return -EFSCORRUPTED;
6279 	}
6280 
6281 	journal = EXT4_SB(sb)->s_journal;
6282 
6283 	/*
6284 	 * Now check for any error status which may have been recorded in the
6285 	 * journal by a prior ext4_error() or ext4_abort()
6286 	 */
6287 
6288 	j_errno = jbd2_journal_errno(journal);
6289 	if (j_errno) {
6290 		char nbuf[16];
6291 
6292 		errstr = ext4_decode_error(sb, j_errno, nbuf);
6293 		ext4_warning(sb, "Filesystem error recorded "
6294 			     "from previous mount: %s", errstr);
6295 
6296 		EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
6297 		es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
6298 		j_errno = ext4_commit_super(sb);
6299 		if (j_errno)
6300 			return j_errno;
6301 		ext4_warning(sb, "Marked fs in need of filesystem check.");
6302 
6303 		jbd2_journal_clear_err(journal);
6304 		jbd2_journal_update_sb_errno(journal);
6305 	}
6306 	return 0;
6307 }
6308 
6309 /*
6310  * Force the running and committing transactions to commit,
6311  * and wait on the commit.
6312  */
ext4_force_commit(struct super_block * sb)6313 int ext4_force_commit(struct super_block *sb)
6314 {
6315 	return ext4_journal_force_commit(EXT4_SB(sb)->s_journal);
6316 }
6317 
ext4_sync_fs(struct super_block * sb,int wait)6318 static int ext4_sync_fs(struct super_block *sb, int wait)
6319 {
6320 	int ret = 0;
6321 	tid_t target;
6322 	bool needs_barrier = false;
6323 	struct ext4_sb_info *sbi = EXT4_SB(sb);
6324 
6325 	if (unlikely(ext4_forced_shutdown(sb)))
6326 		return 0;
6327 
6328 	trace_ext4_sync_fs(sb, wait);
6329 	flush_workqueue(sbi->rsv_conversion_wq);
6330 	/*
6331 	 * Writeback quota in non-journalled quota case - journalled quota has
6332 	 * no dirty dquots
6333 	 */
6334 	dquot_writeback_dquots(sb, -1);
6335 	/*
6336 	 * Data writeback is possible w/o journal transaction, so barrier must
6337 	 * being sent at the end of the function. But we can skip it if
6338 	 * transaction_commit will do it for us.
6339 	 */
6340 	if (sbi->s_journal) {
6341 		target = jbd2_get_latest_transaction(sbi->s_journal);
6342 		if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
6343 		    !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
6344 			needs_barrier = true;
6345 
6346 		if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
6347 			if (wait)
6348 				ret = jbd2_log_wait_commit(sbi->s_journal,
6349 							   target);
6350 		}
6351 	} else if (wait && test_opt(sb, BARRIER))
6352 		needs_barrier = true;
6353 	if (needs_barrier) {
6354 		int err;
6355 		err = blkdev_issue_flush(sb->s_bdev);
6356 		if (!ret)
6357 			ret = err;
6358 	}
6359 
6360 	return ret;
6361 }
6362 
6363 /*
6364  * LVM calls this function before a (read-only) snapshot is created.  This
6365  * gives us a chance to flush the journal completely and mark the fs clean.
6366  *
6367  * Note that only this function cannot bring a filesystem to be in a clean
6368  * state independently. It relies on upper layer to stop all data & metadata
6369  * modifications.
6370  */
ext4_freeze(struct super_block * sb)6371 static int ext4_freeze(struct super_block *sb)
6372 {
6373 	int error = 0;
6374 	journal_t *journal = EXT4_SB(sb)->s_journal;
6375 
6376 	if (journal) {
6377 		/* Now we set up the journal barrier. */
6378 		jbd2_journal_lock_updates(journal);
6379 
6380 		/*
6381 		 * Don't clear the needs_recovery flag if we failed to
6382 		 * flush the journal.
6383 		 */
6384 		error = jbd2_journal_flush(journal, 0);
6385 		if (error < 0)
6386 			goto out;
6387 
6388 		/* Journal blocked and flushed, clear needs_recovery flag. */
6389 		ext4_clear_feature_journal_needs_recovery(sb);
6390 		if (ext4_orphan_file_empty(sb))
6391 			ext4_clear_feature_orphan_present(sb);
6392 	}
6393 
6394 	error = ext4_commit_super(sb);
6395 out:
6396 	if (journal)
6397 		/* we rely on upper layer to stop further updates */
6398 		jbd2_journal_unlock_updates(journal);
6399 	return error;
6400 }
6401 
6402 /*
6403  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
6404  * flag here, even though the filesystem is not technically dirty yet.
6405  */
ext4_unfreeze(struct super_block * sb)6406 static int ext4_unfreeze(struct super_block *sb)
6407 {
6408 	if (ext4_forced_shutdown(sb))
6409 		return 0;
6410 
6411 	if (EXT4_SB(sb)->s_journal) {
6412 		/* Reset the needs_recovery flag before the fs is unlocked. */
6413 		ext4_set_feature_journal_needs_recovery(sb);
6414 		if (ext4_has_feature_orphan_file(sb))
6415 			ext4_set_feature_orphan_present(sb);
6416 	}
6417 
6418 	ext4_commit_super(sb);
6419 	return 0;
6420 }
6421 
6422 /*
6423  * Structure to save mount options for ext4_remount's benefit
6424  */
6425 struct ext4_mount_options {
6426 	unsigned long s_mount_opt;
6427 	unsigned long s_mount_opt2;
6428 	kuid_t s_resuid;
6429 	kgid_t s_resgid;
6430 	unsigned long s_commit_interval;
6431 	u32 s_min_batch_time, s_max_batch_time;
6432 #ifdef CONFIG_QUOTA
6433 	int s_jquota_fmt;
6434 	char *s_qf_names[EXT4_MAXQUOTAS];
6435 #endif
6436 };
6437 
__ext4_remount(struct fs_context * fc,struct super_block * sb)6438 static int __ext4_remount(struct fs_context *fc, struct super_block *sb)
6439 {
6440 	struct ext4_fs_context *ctx = fc->fs_private;
6441 	struct ext4_super_block *es;
6442 	struct ext4_sb_info *sbi = EXT4_SB(sb);
6443 	unsigned long old_sb_flags;
6444 	struct ext4_mount_options old_opts;
6445 	ext4_group_t g;
6446 	int err = 0;
6447 	int alloc_ctx;
6448 #ifdef CONFIG_QUOTA
6449 	int enable_quota = 0;
6450 	int i, j;
6451 	char *to_free[EXT4_MAXQUOTAS];
6452 #endif
6453 
6454 
6455 	/* Store the original options */
6456 	old_sb_flags = sb->s_flags;
6457 	old_opts.s_mount_opt = sbi->s_mount_opt;
6458 	old_opts.s_mount_opt2 = sbi->s_mount_opt2;
6459 	old_opts.s_resuid = sbi->s_resuid;
6460 	old_opts.s_resgid = sbi->s_resgid;
6461 	old_opts.s_commit_interval = sbi->s_commit_interval;
6462 	old_opts.s_min_batch_time = sbi->s_min_batch_time;
6463 	old_opts.s_max_batch_time = sbi->s_max_batch_time;
6464 #ifdef CONFIG_QUOTA
6465 	old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
6466 	for (i = 0; i < EXT4_MAXQUOTAS; i++)
6467 		if (sbi->s_qf_names[i]) {
6468 			char *qf_name = get_qf_name(sb, sbi, i);
6469 
6470 			old_opts.s_qf_names[i] = kstrdup(qf_name, GFP_KERNEL);
6471 			if (!old_opts.s_qf_names[i]) {
6472 				for (j = 0; j < i; j++)
6473 					kfree(old_opts.s_qf_names[j]);
6474 				return -ENOMEM;
6475 			}
6476 		} else
6477 			old_opts.s_qf_names[i] = NULL;
6478 #endif
6479 	if (!(ctx->spec & EXT4_SPEC_JOURNAL_IOPRIO)) {
6480 		if (sbi->s_journal && sbi->s_journal->j_task->io_context)
6481 			ctx->journal_ioprio =
6482 				sbi->s_journal->j_task->io_context->ioprio;
6483 		else
6484 			ctx->journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
6485 
6486 	}
6487 
6488 	/*
6489 	 * Changing the DIOREAD_NOLOCK or DELALLOC mount options may cause
6490 	 * two calls to ext4_should_dioread_nolock() to return inconsistent
6491 	 * values, triggering WARN_ON in ext4_add_complete_io(). we grab
6492 	 * here s_writepages_rwsem to avoid race between writepages ops and
6493 	 * remount.
6494 	 */
6495 	alloc_ctx = ext4_writepages_down_write(sb);
6496 	ext4_apply_options(fc, sb);
6497 	ext4_writepages_up_write(sb, alloc_ctx);
6498 
6499 	if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
6500 	    test_opt(sb, JOURNAL_CHECKSUM)) {
6501 		ext4_msg(sb, KERN_ERR, "changing journal_checksum "
6502 			 "during remount not supported; ignoring");
6503 		sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
6504 	}
6505 
6506 	if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
6507 		if (test_opt2(sb, EXPLICIT_DELALLOC)) {
6508 			ext4_msg(sb, KERN_ERR, "can't mount with "
6509 				 "both data=journal and delalloc");
6510 			err = -EINVAL;
6511 			goto restore_opts;
6512 		}
6513 		if (test_opt(sb, DIOREAD_NOLOCK)) {
6514 			ext4_msg(sb, KERN_ERR, "can't mount with "
6515 				 "both data=journal and dioread_nolock");
6516 			err = -EINVAL;
6517 			goto restore_opts;
6518 		}
6519 	} else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
6520 		if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
6521 			ext4_msg(sb, KERN_ERR, "can't mount with "
6522 				"journal_async_commit in data=ordered mode");
6523 			err = -EINVAL;
6524 			goto restore_opts;
6525 		}
6526 	}
6527 
6528 	if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
6529 		ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
6530 		err = -EINVAL;
6531 		goto restore_opts;
6532 	}
6533 
6534 	if (test_opt2(sb, ABORT))
6535 		ext4_abort(sb, ESHUTDOWN, "Abort forced by user");
6536 
6537 	sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
6538 		(test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
6539 
6540 	es = sbi->s_es;
6541 
6542 	if (sbi->s_journal) {
6543 		ext4_init_journal_params(sb, sbi->s_journal);
6544 		set_task_ioprio(sbi->s_journal->j_task, ctx->journal_ioprio);
6545 	}
6546 
6547 	/* Flush outstanding errors before changing fs state */
6548 	flush_work(&sbi->s_sb_upd_work);
6549 
6550 	if ((bool)(fc->sb_flags & SB_RDONLY) != sb_rdonly(sb)) {
6551 		if (ext4_forced_shutdown(sb)) {
6552 			err = -EROFS;
6553 			goto restore_opts;
6554 		}
6555 
6556 		if (fc->sb_flags & SB_RDONLY) {
6557 			err = sync_filesystem(sb);
6558 			if (err < 0)
6559 				goto restore_opts;
6560 			err = dquot_suspend(sb, -1);
6561 			if (err < 0)
6562 				goto restore_opts;
6563 
6564 			/*
6565 			 * First of all, the unconditional stuff we have to do
6566 			 * to disable replay of the journal when we next remount
6567 			 */
6568 			sb->s_flags |= SB_RDONLY;
6569 
6570 			/*
6571 			 * OK, test if we are remounting a valid rw partition
6572 			 * readonly, and if so set the rdonly flag and then
6573 			 * mark the partition as valid again.
6574 			 */
6575 			if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
6576 			    (sbi->s_mount_state & EXT4_VALID_FS))
6577 				es->s_state = cpu_to_le16(sbi->s_mount_state);
6578 
6579 			if (sbi->s_journal) {
6580 				/*
6581 				 * We let remount-ro finish even if marking fs
6582 				 * as clean failed...
6583 				 */
6584 				ext4_mark_recovery_complete(sb, es);
6585 			}
6586 		} else {
6587 			/* Make sure we can mount this feature set readwrite */
6588 			if (ext4_has_feature_readonly(sb) ||
6589 			    !ext4_feature_set_ok(sb, 0)) {
6590 				err = -EROFS;
6591 				goto restore_opts;
6592 			}
6593 			/*
6594 			 * Make sure the group descriptor checksums
6595 			 * are sane.  If they aren't, refuse to remount r/w.
6596 			 */
6597 			for (g = 0; g < sbi->s_groups_count; g++) {
6598 				struct ext4_group_desc *gdp =
6599 					ext4_get_group_desc(sb, g, NULL);
6600 
6601 				if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
6602 					ext4_msg(sb, KERN_ERR,
6603 	       "ext4_remount: Checksum for group %u failed (%u!=%u)",
6604 		g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
6605 					       le16_to_cpu(gdp->bg_checksum));
6606 					err = -EFSBADCRC;
6607 					goto restore_opts;
6608 				}
6609 			}
6610 
6611 			/*
6612 			 * If we have an unprocessed orphan list hanging
6613 			 * around from a previously readonly bdev mount,
6614 			 * require a full umount/remount for now.
6615 			 */
6616 			if (es->s_last_orphan || !ext4_orphan_file_empty(sb)) {
6617 				ext4_msg(sb, KERN_WARNING, "Couldn't "
6618 				       "remount RDWR because of unprocessed "
6619 				       "orphan inode list.  Please "
6620 				       "umount/remount instead");
6621 				err = -EINVAL;
6622 				goto restore_opts;
6623 			}
6624 
6625 			/*
6626 			 * Mounting a RDONLY partition read-write, so reread
6627 			 * and store the current valid flag.  (It may have
6628 			 * been changed by e2fsck since we originally mounted
6629 			 * the partition.)
6630 			 */
6631 			if (sbi->s_journal) {
6632 				err = ext4_clear_journal_err(sb, es);
6633 				if (err)
6634 					goto restore_opts;
6635 			}
6636 			sbi->s_mount_state = (le16_to_cpu(es->s_state) &
6637 					      ~EXT4_FC_REPLAY);
6638 
6639 			err = ext4_setup_super(sb, es, 0);
6640 			if (err)
6641 				goto restore_opts;
6642 
6643 			sb->s_flags &= ~SB_RDONLY;
6644 			if (ext4_has_feature_mmp(sb)) {
6645 				err = ext4_multi_mount_protect(sb,
6646 						le64_to_cpu(es->s_mmp_block));
6647 				if (err)
6648 					goto restore_opts;
6649 			}
6650 #ifdef CONFIG_QUOTA
6651 			enable_quota = 1;
6652 #endif
6653 		}
6654 	}
6655 
6656 	/*
6657 	 * Handle creation of system zone data early because it can fail.
6658 	 * Releasing of existing data is done when we are sure remount will
6659 	 * succeed.
6660 	 */
6661 	if (test_opt(sb, BLOCK_VALIDITY) && !sbi->s_system_blks) {
6662 		err = ext4_setup_system_zone(sb);
6663 		if (err)
6664 			goto restore_opts;
6665 	}
6666 
6667 	if (sbi->s_journal == NULL && !(old_sb_flags & SB_RDONLY)) {
6668 		err = ext4_commit_super(sb);
6669 		if (err)
6670 			goto restore_opts;
6671 	}
6672 
6673 #ifdef CONFIG_QUOTA
6674 	if (enable_quota) {
6675 		if (sb_any_quota_suspended(sb))
6676 			dquot_resume(sb, -1);
6677 		else if (ext4_has_feature_quota(sb)) {
6678 			err = ext4_enable_quotas(sb);
6679 			if (err)
6680 				goto restore_opts;
6681 		}
6682 	}
6683 	/* Release old quota file names */
6684 	for (i = 0; i < EXT4_MAXQUOTAS; i++)
6685 		kfree(old_opts.s_qf_names[i]);
6686 #endif
6687 	if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
6688 		ext4_release_system_zone(sb);
6689 
6690 	/*
6691 	 * Reinitialize lazy itable initialization thread based on
6692 	 * current settings
6693 	 */
6694 	if (sb_rdonly(sb) || !test_opt(sb, INIT_INODE_TABLE))
6695 		ext4_unregister_li_request(sb);
6696 	else {
6697 		ext4_group_t first_not_zeroed;
6698 		first_not_zeroed = ext4_has_uninit_itable(sb);
6699 		ext4_register_li_request(sb, first_not_zeroed);
6700 	}
6701 
6702 	if (!ext4_has_feature_mmp(sb) || sb_rdonly(sb))
6703 		ext4_stop_mmpd(sbi);
6704 
6705 	return 0;
6706 
6707 restore_opts:
6708 	/*
6709 	 * If there was a failing r/w to ro transition, we may need to
6710 	 * re-enable quota
6711 	 */
6712 	if (sb_rdonly(sb) && !(old_sb_flags & SB_RDONLY) &&
6713 	    sb_any_quota_suspended(sb))
6714 		dquot_resume(sb, -1);
6715 
6716 	alloc_ctx = ext4_writepages_down_write(sb);
6717 	sb->s_flags = old_sb_flags;
6718 	sbi->s_mount_opt = old_opts.s_mount_opt;
6719 	sbi->s_mount_opt2 = old_opts.s_mount_opt2;
6720 	sbi->s_resuid = old_opts.s_resuid;
6721 	sbi->s_resgid = old_opts.s_resgid;
6722 	sbi->s_commit_interval = old_opts.s_commit_interval;
6723 	sbi->s_min_batch_time = old_opts.s_min_batch_time;
6724 	sbi->s_max_batch_time = old_opts.s_max_batch_time;
6725 	ext4_writepages_up_write(sb, alloc_ctx);
6726 
6727 	if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
6728 		ext4_release_system_zone(sb);
6729 #ifdef CONFIG_QUOTA
6730 	sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
6731 	for (i = 0; i < EXT4_MAXQUOTAS; i++) {
6732 		to_free[i] = get_qf_name(sb, sbi, i);
6733 		rcu_assign_pointer(sbi->s_qf_names[i], old_opts.s_qf_names[i]);
6734 	}
6735 	synchronize_rcu();
6736 	for (i = 0; i < EXT4_MAXQUOTAS; i++)
6737 		kfree(to_free[i]);
6738 #endif
6739 	if (!ext4_has_feature_mmp(sb) || sb_rdonly(sb))
6740 		ext4_stop_mmpd(sbi);
6741 	return err;
6742 }
6743 
ext4_reconfigure(struct fs_context * fc)6744 static int ext4_reconfigure(struct fs_context *fc)
6745 {
6746 	struct super_block *sb = fc->root->d_sb;
6747 	int ret;
6748 
6749 	fc->s_fs_info = EXT4_SB(sb);
6750 
6751 	ret = ext4_check_opt_consistency(fc, sb);
6752 	if (ret < 0)
6753 		return ret;
6754 
6755 	ret = __ext4_remount(fc, sb);
6756 	if (ret < 0)
6757 		return ret;
6758 
6759 	ext4_msg(sb, KERN_INFO, "re-mounted %pU %s. Quota mode: %s.",
6760 		 &sb->s_uuid, sb_rdonly(sb) ? "ro" : "r/w",
6761 		 ext4_quota_mode(sb));
6762 
6763 	return 0;
6764 }
6765 
6766 #ifdef CONFIG_QUOTA
ext4_statfs_project(struct super_block * sb,kprojid_t projid,struct kstatfs * buf)6767 static int ext4_statfs_project(struct super_block *sb,
6768 			       kprojid_t projid, struct kstatfs *buf)
6769 {
6770 	struct kqid qid;
6771 	struct dquot *dquot;
6772 	u64 limit;
6773 	u64 curblock;
6774 
6775 	qid = make_kqid_projid(projid);
6776 	dquot = dqget(sb, qid);
6777 	if (IS_ERR(dquot))
6778 		return PTR_ERR(dquot);
6779 	spin_lock(&dquot->dq_dqb_lock);
6780 
6781 	limit = min_not_zero(dquot->dq_dqb.dqb_bsoftlimit,
6782 			     dquot->dq_dqb.dqb_bhardlimit);
6783 	limit >>= sb->s_blocksize_bits;
6784 
6785 	if (limit && buf->f_blocks > limit) {
6786 		curblock = (dquot->dq_dqb.dqb_curspace +
6787 			    dquot->dq_dqb.dqb_rsvspace) >> sb->s_blocksize_bits;
6788 		buf->f_blocks = limit;
6789 		buf->f_bfree = buf->f_bavail =
6790 			(buf->f_blocks > curblock) ?
6791 			 (buf->f_blocks - curblock) : 0;
6792 	}
6793 
6794 	limit = min_not_zero(dquot->dq_dqb.dqb_isoftlimit,
6795 			     dquot->dq_dqb.dqb_ihardlimit);
6796 	if (limit && buf->f_files > limit) {
6797 		buf->f_files = limit;
6798 		buf->f_ffree =
6799 			(buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
6800 			 (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
6801 	}
6802 
6803 	spin_unlock(&dquot->dq_dqb_lock);
6804 	dqput(dquot);
6805 	return 0;
6806 }
6807 #endif
6808 
ext4_statfs(struct dentry * dentry,struct kstatfs * buf)6809 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
6810 {
6811 	struct super_block *sb = dentry->d_sb;
6812 	struct ext4_sb_info *sbi = EXT4_SB(sb);
6813 	struct ext4_super_block *es = sbi->s_es;
6814 	ext4_fsblk_t overhead = 0, resv_blocks;
6815 	s64 bfree;
6816 	resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
6817 
6818 	if (!test_opt(sb, MINIX_DF))
6819 		overhead = sbi->s_overhead;
6820 
6821 	buf->f_type = EXT4_SUPER_MAGIC;
6822 	buf->f_bsize = sb->s_blocksize;
6823 	buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
6824 	bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
6825 		percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
6826 	/* prevent underflow in case that few free space is available */
6827 	buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
6828 	buf->f_bavail = buf->f_bfree -
6829 			(ext4_r_blocks_count(es) + resv_blocks);
6830 	if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
6831 		buf->f_bavail = 0;
6832 	buf->f_files = le32_to_cpu(es->s_inodes_count);
6833 	buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
6834 	buf->f_namelen = EXT4_NAME_LEN;
6835 	buf->f_fsid = uuid_to_fsid(es->s_uuid);
6836 
6837 #ifdef CONFIG_QUOTA
6838 	if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
6839 	    sb_has_quota_limits_enabled(sb, PRJQUOTA))
6840 		ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
6841 #endif
6842 	return 0;
6843 }
6844 
6845 
6846 #ifdef CONFIG_QUOTA
6847 
6848 /*
6849  * Helper functions so that transaction is started before we acquire dqio_sem
6850  * to keep correct lock ordering of transaction > dqio_sem
6851  */
dquot_to_inode(struct dquot * dquot)6852 static inline struct inode *dquot_to_inode(struct dquot *dquot)
6853 {
6854 	return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
6855 }
6856 
ext4_write_dquot(struct dquot * dquot)6857 static int ext4_write_dquot(struct dquot *dquot)
6858 {
6859 	int ret, err;
6860 	handle_t *handle;
6861 	struct inode *inode;
6862 
6863 	inode = dquot_to_inode(dquot);
6864 	handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
6865 				    EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
6866 	if (IS_ERR(handle))
6867 		return PTR_ERR(handle);
6868 	ret = dquot_commit(dquot);
6869 	if (ret < 0)
6870 		ext4_error_err(dquot->dq_sb, -ret,
6871 			       "Failed to commit dquot type %d",
6872 			       dquot->dq_id.type);
6873 	err = ext4_journal_stop(handle);
6874 	if (!ret)
6875 		ret = err;
6876 	return ret;
6877 }
6878 
ext4_acquire_dquot(struct dquot * dquot)6879 static int ext4_acquire_dquot(struct dquot *dquot)
6880 {
6881 	int ret, err;
6882 	handle_t *handle;
6883 
6884 	handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6885 				    EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
6886 	if (IS_ERR(handle))
6887 		return PTR_ERR(handle);
6888 	ret = dquot_acquire(dquot);
6889 	if (ret < 0)
6890 		ext4_error_err(dquot->dq_sb, -ret,
6891 			      "Failed to acquire dquot type %d",
6892 			      dquot->dq_id.type);
6893 	err = ext4_journal_stop(handle);
6894 	if (!ret)
6895 		ret = err;
6896 	return ret;
6897 }
6898 
ext4_release_dquot(struct dquot * dquot)6899 static int ext4_release_dquot(struct dquot *dquot)
6900 {
6901 	int ret, err;
6902 	handle_t *handle;
6903 
6904 	handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6905 				    EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
6906 	if (IS_ERR(handle)) {
6907 		/* Release dquot anyway to avoid endless cycle in dqput() */
6908 		dquot_release(dquot);
6909 		return PTR_ERR(handle);
6910 	}
6911 	ret = dquot_release(dquot);
6912 	if (ret < 0)
6913 		ext4_error_err(dquot->dq_sb, -ret,
6914 			       "Failed to release dquot type %d",
6915 			       dquot->dq_id.type);
6916 	err = ext4_journal_stop(handle);
6917 	if (!ret)
6918 		ret = err;
6919 	return ret;
6920 }
6921 
ext4_mark_dquot_dirty(struct dquot * dquot)6922 static int ext4_mark_dquot_dirty(struct dquot *dquot)
6923 {
6924 	struct super_block *sb = dquot->dq_sb;
6925 
6926 	if (ext4_is_quota_journalled(sb)) {
6927 		dquot_mark_dquot_dirty(dquot);
6928 		return ext4_write_dquot(dquot);
6929 	} else {
6930 		return dquot_mark_dquot_dirty(dquot);
6931 	}
6932 }
6933 
ext4_write_info(struct super_block * sb,int type)6934 static int ext4_write_info(struct super_block *sb, int type)
6935 {
6936 	int ret, err;
6937 	handle_t *handle;
6938 
6939 	/* Data block + inode block */
6940 	handle = ext4_journal_start_sb(sb, EXT4_HT_QUOTA, 2);
6941 	if (IS_ERR(handle))
6942 		return PTR_ERR(handle);
6943 	ret = dquot_commit_info(sb, type);
6944 	err = ext4_journal_stop(handle);
6945 	if (!ret)
6946 		ret = err;
6947 	return ret;
6948 }
6949 
lockdep_set_quota_inode(struct inode * inode,int subclass)6950 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
6951 {
6952 	struct ext4_inode_info *ei = EXT4_I(inode);
6953 
6954 	/* The first argument of lockdep_set_subclass has to be
6955 	 * *exactly* the same as the argument to init_rwsem() --- in
6956 	 * this case, in init_once() --- or lockdep gets unhappy
6957 	 * because the name of the lock is set using the
6958 	 * stringification of the argument to init_rwsem().
6959 	 */
6960 	(void) ei;	/* shut up clang warning if !CONFIG_LOCKDEP */
6961 	lockdep_set_subclass(&ei->i_data_sem, subclass);
6962 }
6963 
6964 /*
6965  * Standard function to be called on quota_on
6966  */
ext4_quota_on(struct super_block * sb,int type,int format_id,const struct path * path)6967 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
6968 			 const struct path *path)
6969 {
6970 	int err;
6971 
6972 	if (!test_opt(sb, QUOTA))
6973 		return -EINVAL;
6974 
6975 	/* Quotafile not on the same filesystem? */
6976 	if (path->dentry->d_sb != sb)
6977 		return -EXDEV;
6978 
6979 	/* Quota already enabled for this file? */
6980 	if (IS_NOQUOTA(d_inode(path->dentry)))
6981 		return -EBUSY;
6982 
6983 	/* Journaling quota? */
6984 	if (EXT4_SB(sb)->s_qf_names[type]) {
6985 		/* Quotafile not in fs root? */
6986 		if (path->dentry->d_parent != sb->s_root)
6987 			ext4_msg(sb, KERN_WARNING,
6988 				"Quota file not on filesystem root. "
6989 				"Journaled quota will not work");
6990 		sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
6991 	} else {
6992 		/*
6993 		 * Clear the flag just in case mount options changed since
6994 		 * last time.
6995 		 */
6996 		sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
6997 	}
6998 
6999 	lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
7000 	err = dquot_quota_on(sb, type, format_id, path);
7001 	if (!err) {
7002 		struct inode *inode = d_inode(path->dentry);
7003 		handle_t *handle;
7004 
7005 		/*
7006 		 * Set inode flags to prevent userspace from messing with quota
7007 		 * files. If this fails, we return success anyway since quotas
7008 		 * are already enabled and this is not a hard failure.
7009 		 */
7010 		inode_lock(inode);
7011 		handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
7012 		if (IS_ERR(handle))
7013 			goto unlock_inode;
7014 		EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
7015 		inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
7016 				S_NOATIME | S_IMMUTABLE);
7017 		err = ext4_mark_inode_dirty(handle, inode);
7018 		ext4_journal_stop(handle);
7019 	unlock_inode:
7020 		inode_unlock(inode);
7021 		if (err)
7022 			dquot_quota_off(sb, type);
7023 	}
7024 	if (err)
7025 		lockdep_set_quota_inode(path->dentry->d_inode,
7026 					     I_DATA_SEM_NORMAL);
7027 	return err;
7028 }
7029 
ext4_check_quota_inum(int type,unsigned long qf_inum)7030 static inline bool ext4_check_quota_inum(int type, unsigned long qf_inum)
7031 {
7032 	switch (type) {
7033 	case USRQUOTA:
7034 		return qf_inum == EXT4_USR_QUOTA_INO;
7035 	case GRPQUOTA:
7036 		return qf_inum == EXT4_GRP_QUOTA_INO;
7037 	case PRJQUOTA:
7038 		return qf_inum >= EXT4_GOOD_OLD_FIRST_INO;
7039 	default:
7040 		BUG();
7041 	}
7042 }
7043 
ext4_quota_enable(struct super_block * sb,int type,int format_id,unsigned int flags)7044 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
7045 			     unsigned int flags)
7046 {
7047 	int err;
7048 	struct inode *qf_inode;
7049 	unsigned long qf_inums[EXT4_MAXQUOTAS] = {
7050 		le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
7051 		le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
7052 		le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
7053 	};
7054 
7055 	BUG_ON(!ext4_has_feature_quota(sb));
7056 
7057 	if (!qf_inums[type])
7058 		return -EPERM;
7059 
7060 	if (!ext4_check_quota_inum(type, qf_inums[type])) {
7061 		ext4_error(sb, "Bad quota inum: %lu, type: %d",
7062 				qf_inums[type], type);
7063 		return -EUCLEAN;
7064 	}
7065 
7066 	qf_inode = ext4_iget(sb, qf_inums[type], EXT4_IGET_SPECIAL);
7067 	if (IS_ERR(qf_inode)) {
7068 		ext4_error(sb, "Bad quota inode: %lu, type: %d",
7069 				qf_inums[type], type);
7070 		return PTR_ERR(qf_inode);
7071 	}
7072 
7073 	/* Don't account quota for quota files to avoid recursion */
7074 	qf_inode->i_flags |= S_NOQUOTA;
7075 	lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
7076 	err = dquot_load_quota_inode(qf_inode, type, format_id, flags);
7077 	if (err)
7078 		lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
7079 	iput(qf_inode);
7080 
7081 	return err;
7082 }
7083 
7084 /* Enable usage tracking for all quota types. */
ext4_enable_quotas(struct super_block * sb)7085 int ext4_enable_quotas(struct super_block *sb)
7086 {
7087 	int type, err = 0;
7088 	unsigned long qf_inums[EXT4_MAXQUOTAS] = {
7089 		le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
7090 		le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
7091 		le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
7092 	};
7093 	bool quota_mopt[EXT4_MAXQUOTAS] = {
7094 		test_opt(sb, USRQUOTA),
7095 		test_opt(sb, GRPQUOTA),
7096 		test_opt(sb, PRJQUOTA),
7097 	};
7098 
7099 	sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
7100 	for (type = 0; type < EXT4_MAXQUOTAS; type++) {
7101 		if (qf_inums[type]) {
7102 			err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
7103 				DQUOT_USAGE_ENABLED |
7104 				(quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
7105 			if (err) {
7106 				ext4_warning(sb,
7107 					"Failed to enable quota tracking "
7108 					"(type=%d, err=%d, ino=%lu). "
7109 					"Please run e2fsck to fix.", type,
7110 					err, qf_inums[type]);
7111 
7112 				ext4_quotas_off(sb, type);
7113 				return err;
7114 			}
7115 		}
7116 	}
7117 	return 0;
7118 }
7119 
ext4_quota_off(struct super_block * sb,int type)7120 static int ext4_quota_off(struct super_block *sb, int type)
7121 {
7122 	struct inode *inode = sb_dqopt(sb)->files[type];
7123 	handle_t *handle;
7124 	int err;
7125 
7126 	/* Force all delayed allocation blocks to be allocated.
7127 	 * Caller already holds s_umount sem */
7128 	if (test_opt(sb, DELALLOC))
7129 		sync_filesystem(sb);
7130 
7131 	if (!inode || !igrab(inode))
7132 		goto out;
7133 
7134 	err = dquot_quota_off(sb, type);
7135 	if (err || ext4_has_feature_quota(sb))
7136 		goto out_put;
7137 	/*
7138 	 * When the filesystem was remounted read-only first, we cannot cleanup
7139 	 * inode flags here. Bad luck but people should be using QUOTA feature
7140 	 * these days anyway.
7141 	 */
7142 	if (sb_rdonly(sb))
7143 		goto out_put;
7144 
7145 	inode_lock(inode);
7146 	/*
7147 	 * Update modification times of quota files when userspace can
7148 	 * start looking at them. If we fail, we return success anyway since
7149 	 * this is not a hard failure and quotas are already disabled.
7150 	 */
7151 	handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
7152 	if (IS_ERR(handle)) {
7153 		err = PTR_ERR(handle);
7154 		goto out_unlock;
7155 	}
7156 	EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
7157 	inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
7158 	inode->i_mtime = inode_set_ctime_current(inode);
7159 	err = ext4_mark_inode_dirty(handle, inode);
7160 	ext4_journal_stop(handle);
7161 out_unlock:
7162 	inode_unlock(inode);
7163 out_put:
7164 	lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
7165 	iput(inode);
7166 	return err;
7167 out:
7168 	return dquot_quota_off(sb, type);
7169 }
7170 
7171 /* Read data from quotafile - avoid pagecache and such because we cannot afford
7172  * acquiring the locks... As quota files are never truncated and quota code
7173  * itself serializes the operations (and no one else should touch the files)
7174  * we don't have to be afraid of races */
ext4_quota_read(struct super_block * sb,int type,char * data,size_t len,loff_t off)7175 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
7176 			       size_t len, loff_t off)
7177 {
7178 	struct inode *inode = sb_dqopt(sb)->files[type];
7179 	ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
7180 	int offset = off & (sb->s_blocksize - 1);
7181 	int tocopy;
7182 	size_t toread;
7183 	struct buffer_head *bh;
7184 	loff_t i_size = i_size_read(inode);
7185 
7186 	if (off > i_size)
7187 		return 0;
7188 	if (off+len > i_size)
7189 		len = i_size-off;
7190 	toread = len;
7191 	while (toread > 0) {
7192 		tocopy = min_t(unsigned long, sb->s_blocksize - offset, toread);
7193 		bh = ext4_bread(NULL, inode, blk, 0);
7194 		if (IS_ERR(bh))
7195 			return PTR_ERR(bh);
7196 		if (!bh)	/* A hole? */
7197 			memset(data, 0, tocopy);
7198 		else
7199 			memcpy(data, bh->b_data+offset, tocopy);
7200 		brelse(bh);
7201 		offset = 0;
7202 		toread -= tocopy;
7203 		data += tocopy;
7204 		blk++;
7205 	}
7206 	return len;
7207 }
7208 
7209 /* Write to quotafile (we know the transaction is already started and has
7210  * enough credits) */
ext4_quota_write(struct super_block * sb,int type,const char * data,size_t len,loff_t off)7211 static ssize_t ext4_quota_write(struct super_block *sb, int type,
7212 				const char *data, size_t len, loff_t off)
7213 {
7214 	struct inode *inode = sb_dqopt(sb)->files[type];
7215 	ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
7216 	int err = 0, err2 = 0, offset = off & (sb->s_blocksize - 1);
7217 	int retries = 0;
7218 	struct buffer_head *bh;
7219 	handle_t *handle = journal_current_handle();
7220 
7221 	if (!handle) {
7222 		ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
7223 			" cancelled because transaction is not started",
7224 			(unsigned long long)off, (unsigned long long)len);
7225 		return -EIO;
7226 	}
7227 	/*
7228 	 * Since we account only one data block in transaction credits,
7229 	 * then it is impossible to cross a block boundary.
7230 	 */
7231 	if (sb->s_blocksize - offset < len) {
7232 		ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
7233 			" cancelled because not block aligned",
7234 			(unsigned long long)off, (unsigned long long)len);
7235 		return -EIO;
7236 	}
7237 
7238 	do {
7239 		bh = ext4_bread(handle, inode, blk,
7240 				EXT4_GET_BLOCKS_CREATE |
7241 				EXT4_GET_BLOCKS_METADATA_NOFAIL);
7242 	} while (PTR_ERR(bh) == -ENOSPC &&
7243 		 ext4_should_retry_alloc(inode->i_sb, &retries));
7244 	if (IS_ERR(bh))
7245 		return PTR_ERR(bh);
7246 	if (!bh)
7247 		goto out;
7248 	BUFFER_TRACE(bh, "get write access");
7249 	err = ext4_journal_get_write_access(handle, sb, bh, EXT4_JTR_NONE);
7250 	if (err) {
7251 		brelse(bh);
7252 		return err;
7253 	}
7254 	lock_buffer(bh);
7255 	memcpy(bh->b_data+offset, data, len);
7256 	flush_dcache_page(bh->b_page);
7257 	unlock_buffer(bh);
7258 	err = ext4_handle_dirty_metadata(handle, NULL, bh);
7259 	brelse(bh);
7260 out:
7261 	if (inode->i_size < off + len) {
7262 		i_size_write(inode, off + len);
7263 		EXT4_I(inode)->i_disksize = inode->i_size;
7264 		err2 = ext4_mark_inode_dirty(handle, inode);
7265 		if (unlikely(err2 && !err))
7266 			err = err2;
7267 	}
7268 	return err ? err : len;
7269 }
7270 #endif
7271 
7272 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
register_as_ext2(void)7273 static inline void register_as_ext2(void)
7274 {
7275 	int err = register_filesystem(&ext2_fs_type);
7276 	if (err)
7277 		printk(KERN_WARNING
7278 		       "EXT4-fs: Unable to register as ext2 (%d)\n", err);
7279 }
7280 
unregister_as_ext2(void)7281 static inline void unregister_as_ext2(void)
7282 {
7283 	unregister_filesystem(&ext2_fs_type);
7284 }
7285 
ext2_feature_set_ok(struct super_block * sb)7286 static inline int ext2_feature_set_ok(struct super_block *sb)
7287 {
7288 	if (ext4_has_unknown_ext2_incompat_features(sb))
7289 		return 0;
7290 	if (sb_rdonly(sb))
7291 		return 1;
7292 	if (ext4_has_unknown_ext2_ro_compat_features(sb))
7293 		return 0;
7294 	return 1;
7295 }
7296 #else
register_as_ext2(void)7297 static inline void register_as_ext2(void) { }
unregister_as_ext2(void)7298 static inline void unregister_as_ext2(void) { }
ext2_feature_set_ok(struct super_block * sb)7299 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
7300 #endif
7301 
register_as_ext3(void)7302 static inline void register_as_ext3(void)
7303 {
7304 	int err = register_filesystem(&ext3_fs_type);
7305 	if (err)
7306 		printk(KERN_WARNING
7307 		       "EXT4-fs: Unable to register as ext3 (%d)\n", err);
7308 }
7309 
unregister_as_ext3(void)7310 static inline void unregister_as_ext3(void)
7311 {
7312 	unregister_filesystem(&ext3_fs_type);
7313 }
7314 
ext3_feature_set_ok(struct super_block * sb)7315 static inline int ext3_feature_set_ok(struct super_block *sb)
7316 {
7317 	if (ext4_has_unknown_ext3_incompat_features(sb))
7318 		return 0;
7319 	if (!ext4_has_feature_journal(sb))
7320 		return 0;
7321 	if (sb_rdonly(sb))
7322 		return 1;
7323 	if (ext4_has_unknown_ext3_ro_compat_features(sb))
7324 		return 0;
7325 	return 1;
7326 }
7327 
ext4_kill_sb(struct super_block * sb)7328 static void ext4_kill_sb(struct super_block *sb)
7329 {
7330 	struct ext4_sb_info *sbi = EXT4_SB(sb);
7331 	struct block_device *journal_bdev = sbi ? sbi->s_journal_bdev : NULL;
7332 
7333 	kill_block_super(sb);
7334 
7335 	if (journal_bdev)
7336 		blkdev_put(journal_bdev, sb);
7337 }
7338 
7339 static struct file_system_type ext4_fs_type = {
7340 	.owner			= THIS_MODULE,
7341 	.name			= "ext4",
7342 	.init_fs_context	= ext4_init_fs_context,
7343 	.parameters		= ext4_param_specs,
7344 	.kill_sb		= ext4_kill_sb,
7345 	.fs_flags		= FS_REQUIRES_DEV | FS_ALLOW_IDMAP,
7346 };
7347 MODULE_ALIAS_FS("ext4");
7348 
7349 /* Shared across all ext4 file systems */
7350 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
7351 
ext4_init_fs(void)7352 static int __init ext4_init_fs(void)
7353 {
7354 	int i, err;
7355 
7356 	ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
7357 	ext4_li_info = NULL;
7358 
7359 	/* Build-time check for flags consistency */
7360 	ext4_check_flag_values();
7361 
7362 	for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
7363 		init_waitqueue_head(&ext4__ioend_wq[i]);
7364 
7365 	err = ext4_init_es();
7366 	if (err)
7367 		return err;
7368 
7369 	err = ext4_init_pending();
7370 	if (err)
7371 		goto out7;
7372 
7373 	err = ext4_init_post_read_processing();
7374 	if (err)
7375 		goto out6;
7376 
7377 	err = ext4_init_pageio();
7378 	if (err)
7379 		goto out5;
7380 
7381 	err = ext4_init_system_zone();
7382 	if (err)
7383 		goto out4;
7384 
7385 	err = ext4_init_sysfs();
7386 	if (err)
7387 		goto out3;
7388 
7389 	err = ext4_init_mballoc();
7390 	if (err)
7391 		goto out2;
7392 	err = init_inodecache();
7393 	if (err)
7394 		goto out1;
7395 
7396 	err = ext4_fc_init_dentry_cache();
7397 	if (err)
7398 		goto out05;
7399 
7400 	register_as_ext3();
7401 	register_as_ext2();
7402 	err = register_filesystem(&ext4_fs_type);
7403 	if (err)
7404 		goto out;
7405 
7406 	return 0;
7407 out:
7408 	unregister_as_ext2();
7409 	unregister_as_ext3();
7410 	ext4_fc_destroy_dentry_cache();
7411 out05:
7412 	destroy_inodecache();
7413 out1:
7414 	ext4_exit_mballoc();
7415 out2:
7416 	ext4_exit_sysfs();
7417 out3:
7418 	ext4_exit_system_zone();
7419 out4:
7420 	ext4_exit_pageio();
7421 out5:
7422 	ext4_exit_post_read_processing();
7423 out6:
7424 	ext4_exit_pending();
7425 out7:
7426 	ext4_exit_es();
7427 
7428 	return err;
7429 }
7430 
ext4_exit_fs(void)7431 static void __exit ext4_exit_fs(void)
7432 {
7433 	ext4_destroy_lazyinit_thread();
7434 	unregister_as_ext2();
7435 	unregister_as_ext3();
7436 	unregister_filesystem(&ext4_fs_type);
7437 	ext4_fc_destroy_dentry_cache();
7438 	destroy_inodecache();
7439 	ext4_exit_mballoc();
7440 	ext4_exit_sysfs();
7441 	ext4_exit_system_zone();
7442 	ext4_exit_pageio();
7443 	ext4_exit_post_read_processing();
7444 	ext4_exit_es();
7445 	ext4_exit_pending();
7446 }
7447 
7448 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
7449 MODULE_DESCRIPTION("Fourth Extended Filesystem");
7450 MODULE_LICENSE("GPL");
7451 MODULE_IMPORT_NS(ANDROID_GKI_VFS_EXPORT_ONLY);
7452 MODULE_SOFTDEP("pre: crc32c");
7453 module_init(ext4_init_fs)
7454 module_exit(ext4_exit_fs)
7455