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1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* -*- mode: c; c-basic-offset: 8; -*-
3  * vim: noexpandtab sw=8 ts=8 sts=0:
4  *
5  * suballoc.c
6  *
7  * metadata alloc and free
8  * Inspired by ext3 block groups.
9  *
10  * Copyright (C) 2002, 2004 Oracle.  All rights reserved.
11  */
12 
13 #include <linux/fs.h>
14 #include <linux/types.h>
15 #include <linux/slab.h>
16 #include <linux/highmem.h>
17 
18 #include <cluster/masklog.h>
19 
20 #include "ocfs2.h"
21 
22 #include "alloc.h"
23 #include "blockcheck.h"
24 #include "dlmglue.h"
25 #include "inode.h"
26 #include "journal.h"
27 #include "localalloc.h"
28 #include "suballoc.h"
29 #include "super.h"
30 #include "sysfile.h"
31 #include "uptodate.h"
32 #include "ocfs2_trace.h"
33 
34 #include "buffer_head_io.h"
35 
36 #define NOT_ALLOC_NEW_GROUP		0
37 #define ALLOC_NEW_GROUP			0x1
38 #define ALLOC_GROUPS_FROM_GLOBAL	0x2
39 
40 #define OCFS2_MAX_TO_STEAL		1024
41 
42 struct ocfs2_suballoc_result {
43 	u64		sr_bg_blkno;	/* The bg we allocated from.  Set
44 					   to 0 when a block group is
45 					   contiguous. */
46 	u64		sr_bg_stable_blkno; /*
47 					     * Doesn't change, always
48 					     * set to target block
49 					     * group descriptor
50 					     * block.
51 					     */
52 	u64		sr_blkno;	/* The first allocated block */
53 	unsigned int	sr_bit_offset;	/* The bit in the bg */
54 	unsigned int	sr_bits;	/* How many bits we claimed */
55 };
56 
ocfs2_group_from_res(struct ocfs2_suballoc_result * res)57 static u64 ocfs2_group_from_res(struct ocfs2_suballoc_result *res)
58 {
59 	if (res->sr_blkno == 0)
60 		return 0;
61 
62 	if (res->sr_bg_blkno)
63 		return res->sr_bg_blkno;
64 
65 	return ocfs2_which_suballoc_group(res->sr_blkno, res->sr_bit_offset);
66 }
67 
68 static inline u16 ocfs2_find_victim_chain(struct ocfs2_chain_list *cl);
69 static int ocfs2_block_group_fill(handle_t *handle,
70 				  struct inode *alloc_inode,
71 				  struct buffer_head *bg_bh,
72 				  u64 group_blkno,
73 				  unsigned int group_clusters,
74 				  u16 my_chain,
75 				  struct ocfs2_chain_list *cl);
76 static int ocfs2_block_group_alloc(struct ocfs2_super *osb,
77 				   struct inode *alloc_inode,
78 				   struct buffer_head *bh,
79 				   u64 max_block,
80 				   u64 *last_alloc_group,
81 				   int flags);
82 
83 static int ocfs2_cluster_group_search(struct inode *inode,
84 				      struct buffer_head *group_bh,
85 				      u32 bits_wanted, u32 min_bits,
86 				      u64 max_block,
87 				      struct ocfs2_suballoc_result *res);
88 static int ocfs2_block_group_search(struct inode *inode,
89 				    struct buffer_head *group_bh,
90 				    u32 bits_wanted, u32 min_bits,
91 				    u64 max_block,
92 				    struct ocfs2_suballoc_result *res);
93 static int ocfs2_claim_suballoc_bits(struct ocfs2_alloc_context *ac,
94 				     handle_t *handle,
95 				     u32 bits_wanted,
96 				     u32 min_bits,
97 				     struct ocfs2_suballoc_result *res);
98 static int ocfs2_test_bg_bit_allocatable(struct buffer_head *bg_bh,
99 					 int nr);
100 static int ocfs2_relink_block_group(handle_t *handle,
101 				    struct inode *alloc_inode,
102 				    struct buffer_head *fe_bh,
103 				    struct buffer_head *bg_bh,
104 				    struct buffer_head *prev_bg_bh,
105 				    u16 chain);
106 static inline int ocfs2_block_group_reasonably_empty(struct ocfs2_group_desc *bg,
107 						     u32 wanted);
108 static inline u32 ocfs2_desc_bitmap_to_cluster_off(struct inode *inode,
109 						   u64 bg_blkno,
110 						   u16 bg_bit_off);
111 static inline void ocfs2_block_to_cluster_group(struct inode *inode,
112 						u64 data_blkno,
113 						u64 *bg_blkno,
114 						u16 *bg_bit_off);
115 static int ocfs2_reserve_clusters_with_limit(struct ocfs2_super *osb,
116 					     u32 bits_wanted, u64 max_block,
117 					     int flags,
118 					     struct ocfs2_alloc_context **ac);
119 
ocfs2_free_ac_resource(struct ocfs2_alloc_context * ac)120 void ocfs2_free_ac_resource(struct ocfs2_alloc_context *ac)
121 {
122 	struct inode *inode = ac->ac_inode;
123 
124 	if (inode) {
125 		if (ac->ac_which != OCFS2_AC_USE_LOCAL)
126 			ocfs2_inode_unlock(inode, 1);
127 
128 		inode_unlock(inode);
129 
130 		iput(inode);
131 		ac->ac_inode = NULL;
132 	}
133 	brelse(ac->ac_bh);
134 	ac->ac_bh = NULL;
135 	ac->ac_resv = NULL;
136 	kfree(ac->ac_find_loc_priv);
137 	ac->ac_find_loc_priv = NULL;
138 }
139 
ocfs2_free_alloc_context(struct ocfs2_alloc_context * ac)140 void ocfs2_free_alloc_context(struct ocfs2_alloc_context *ac)
141 {
142 	ocfs2_free_ac_resource(ac);
143 	kfree(ac);
144 }
145 
ocfs2_bits_per_group(struct ocfs2_chain_list * cl)146 static u32 ocfs2_bits_per_group(struct ocfs2_chain_list *cl)
147 {
148 	return (u32)le16_to_cpu(cl->cl_cpg) * (u32)le16_to_cpu(cl->cl_bpc);
149 }
150 
151 #define do_error(fmt, ...)						\
152 do {									\
153 	if (resize)							\
154 		mlog(ML_ERROR, fmt, ##__VA_ARGS__);			\
155 	else								\
156 		return ocfs2_error(sb, fmt, ##__VA_ARGS__);		\
157 } while (0)
158 
ocfs2_validate_gd_self(struct super_block * sb,struct buffer_head * bh,int resize)159 static int ocfs2_validate_gd_self(struct super_block *sb,
160 				  struct buffer_head *bh,
161 				  int resize)
162 {
163 	struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
164 
165 	if (!OCFS2_IS_VALID_GROUP_DESC(gd)) {
166 		do_error("Group descriptor #%llu has bad signature %.*s\n",
167 			 (unsigned long long)bh->b_blocknr, 7,
168 			 gd->bg_signature);
169 	}
170 
171 	if (le64_to_cpu(gd->bg_blkno) != bh->b_blocknr) {
172 		do_error("Group descriptor #%llu has an invalid bg_blkno of %llu\n",
173 			 (unsigned long long)bh->b_blocknr,
174 			 (unsigned long long)le64_to_cpu(gd->bg_blkno));
175 	}
176 
177 	if (le32_to_cpu(gd->bg_generation) != OCFS2_SB(sb)->fs_generation) {
178 		do_error("Group descriptor #%llu has an invalid fs_generation of #%u\n",
179 			 (unsigned long long)bh->b_blocknr,
180 			 le32_to_cpu(gd->bg_generation));
181 	}
182 
183 	if (le16_to_cpu(gd->bg_free_bits_count) > le16_to_cpu(gd->bg_bits)) {
184 		do_error("Group descriptor #%llu has bit count %u but claims that %u are free\n",
185 			 (unsigned long long)bh->b_blocknr,
186 			 le16_to_cpu(gd->bg_bits),
187 			 le16_to_cpu(gd->bg_free_bits_count));
188 	}
189 
190 	if (le16_to_cpu(gd->bg_bits) > (8 * le16_to_cpu(gd->bg_size))) {
191 		do_error("Group descriptor #%llu has bit count %u but max bitmap bits of %u\n",
192 			 (unsigned long long)bh->b_blocknr,
193 			 le16_to_cpu(gd->bg_bits),
194 			 8 * le16_to_cpu(gd->bg_size));
195 	}
196 
197 	return 0;
198 }
199 
ocfs2_validate_gd_parent(struct super_block * sb,struct ocfs2_dinode * di,struct buffer_head * bh,int resize)200 static int ocfs2_validate_gd_parent(struct super_block *sb,
201 				    struct ocfs2_dinode *di,
202 				    struct buffer_head *bh,
203 				    int resize)
204 {
205 	unsigned int max_bits;
206 	struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
207 
208 	if (di->i_blkno != gd->bg_parent_dinode) {
209 		do_error("Group descriptor #%llu has bad parent pointer (%llu, expected %llu)\n",
210 			 (unsigned long long)bh->b_blocknr,
211 			 (unsigned long long)le64_to_cpu(gd->bg_parent_dinode),
212 			 (unsigned long long)le64_to_cpu(di->i_blkno));
213 	}
214 
215 	max_bits = le16_to_cpu(di->id2.i_chain.cl_cpg) * le16_to_cpu(di->id2.i_chain.cl_bpc);
216 	if (le16_to_cpu(gd->bg_bits) > max_bits) {
217 		do_error("Group descriptor #%llu has bit count of %u\n",
218 			 (unsigned long long)bh->b_blocknr,
219 			 le16_to_cpu(gd->bg_bits));
220 	}
221 
222 	/* In resize, we may meet the case bg_chain == cl_next_free_rec. */
223 	if ((le16_to_cpu(gd->bg_chain) >
224 	     le16_to_cpu(di->id2.i_chain.cl_next_free_rec)) ||
225 	    ((le16_to_cpu(gd->bg_chain) ==
226 	     le16_to_cpu(di->id2.i_chain.cl_next_free_rec)) && !resize)) {
227 		do_error("Group descriptor #%llu has bad chain %u\n",
228 			 (unsigned long long)bh->b_blocknr,
229 			 le16_to_cpu(gd->bg_chain));
230 	}
231 
232 	return 0;
233 }
234 
235 #undef do_error
236 
237 /*
238  * This version only prints errors.  It does not fail the filesystem, and
239  * exists only for resize.
240  */
ocfs2_check_group_descriptor(struct super_block * sb,struct ocfs2_dinode * di,struct buffer_head * bh)241 int ocfs2_check_group_descriptor(struct super_block *sb,
242 				 struct ocfs2_dinode *di,
243 				 struct buffer_head *bh)
244 {
245 	int rc;
246 	struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
247 
248 	BUG_ON(!buffer_uptodate(bh));
249 
250 	/*
251 	 * If the ecc fails, we return the error but otherwise
252 	 * leave the filesystem running.  We know any error is
253 	 * local to this block.
254 	 */
255 	rc = ocfs2_validate_meta_ecc(sb, bh->b_data, &gd->bg_check);
256 	if (rc) {
257 		mlog(ML_ERROR,
258 		     "Checksum failed for group descriptor %llu\n",
259 		     (unsigned long long)bh->b_blocknr);
260 	} else
261 		rc = ocfs2_validate_gd_self(sb, bh, 1);
262 	if (!rc)
263 		rc = ocfs2_validate_gd_parent(sb, di, bh, 1);
264 
265 	return rc;
266 }
267 
ocfs2_validate_group_descriptor(struct super_block * sb,struct buffer_head * bh)268 static int ocfs2_validate_group_descriptor(struct super_block *sb,
269 					   struct buffer_head *bh)
270 {
271 	int rc;
272 	struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
273 
274 	trace_ocfs2_validate_group_descriptor(
275 					(unsigned long long)bh->b_blocknr);
276 
277 	BUG_ON(!buffer_uptodate(bh));
278 
279 	/*
280 	 * If the ecc fails, we return the error but otherwise
281 	 * leave the filesystem running.  We know any error is
282 	 * local to this block.
283 	 */
284 	rc = ocfs2_validate_meta_ecc(sb, bh->b_data, &gd->bg_check);
285 	if (rc)
286 		return rc;
287 
288 	/*
289 	 * Errors after here are fatal.
290 	 */
291 
292 	return ocfs2_validate_gd_self(sb, bh, 0);
293 }
294 
ocfs2_read_group_descriptor(struct inode * inode,struct ocfs2_dinode * di,u64 gd_blkno,struct buffer_head ** bh)295 int ocfs2_read_group_descriptor(struct inode *inode, struct ocfs2_dinode *di,
296 				u64 gd_blkno, struct buffer_head **bh)
297 {
298 	int rc;
299 	struct buffer_head *tmp = *bh;
300 
301 	rc = ocfs2_read_block(INODE_CACHE(inode), gd_blkno, &tmp,
302 			      ocfs2_validate_group_descriptor);
303 	if (rc)
304 		goto out;
305 
306 	rc = ocfs2_validate_gd_parent(inode->i_sb, di, tmp, 0);
307 	if (rc) {
308 		brelse(tmp);
309 		goto out;
310 	}
311 
312 	/* If ocfs2_read_block() got us a new bh, pass it up. */
313 	if (!*bh)
314 		*bh = tmp;
315 
316 out:
317 	return rc;
318 }
319 
ocfs2_bg_discontig_add_extent(struct ocfs2_super * osb,struct ocfs2_group_desc * bg,struct ocfs2_chain_list * cl,u64 p_blkno,unsigned int clusters)320 static void ocfs2_bg_discontig_add_extent(struct ocfs2_super *osb,
321 					  struct ocfs2_group_desc *bg,
322 					  struct ocfs2_chain_list *cl,
323 					  u64 p_blkno, unsigned int clusters)
324 {
325 	struct ocfs2_extent_list *el = &bg->bg_list;
326 	struct ocfs2_extent_rec *rec;
327 
328 	BUG_ON(!ocfs2_supports_discontig_bg(osb));
329 	if (!el->l_next_free_rec)
330 		el->l_count = cpu_to_le16(ocfs2_extent_recs_per_gd(osb->sb));
331 	rec = &el->l_recs[le16_to_cpu(el->l_next_free_rec)];
332 	rec->e_blkno = cpu_to_le64(p_blkno);
333 	rec->e_cpos = cpu_to_le32(le16_to_cpu(bg->bg_bits) /
334 				  le16_to_cpu(cl->cl_bpc));
335 	rec->e_leaf_clusters = cpu_to_le16(clusters);
336 	le16_add_cpu(&bg->bg_bits, clusters * le16_to_cpu(cl->cl_bpc));
337 	le16_add_cpu(&bg->bg_free_bits_count,
338 		     clusters * le16_to_cpu(cl->cl_bpc));
339 	le16_add_cpu(&el->l_next_free_rec, 1);
340 }
341 
ocfs2_block_group_fill(handle_t * handle,struct inode * alloc_inode,struct buffer_head * bg_bh,u64 group_blkno,unsigned int group_clusters,u16 my_chain,struct ocfs2_chain_list * cl)342 static int ocfs2_block_group_fill(handle_t *handle,
343 				  struct inode *alloc_inode,
344 				  struct buffer_head *bg_bh,
345 				  u64 group_blkno,
346 				  unsigned int group_clusters,
347 				  u16 my_chain,
348 				  struct ocfs2_chain_list *cl)
349 {
350 	int status = 0;
351 	struct ocfs2_super *osb = OCFS2_SB(alloc_inode->i_sb);
352 	struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) bg_bh->b_data;
353 	struct super_block * sb = alloc_inode->i_sb;
354 
355 	if (((unsigned long long) bg_bh->b_blocknr) != group_blkno) {
356 		status = ocfs2_error(alloc_inode->i_sb,
357 				     "group block (%llu) != b_blocknr (%llu)\n",
358 				     (unsigned long long)group_blkno,
359 				     (unsigned long long) bg_bh->b_blocknr);
360 		goto bail;
361 	}
362 
363 	status = ocfs2_journal_access_gd(handle,
364 					 INODE_CACHE(alloc_inode),
365 					 bg_bh,
366 					 OCFS2_JOURNAL_ACCESS_CREATE);
367 	if (status < 0) {
368 		mlog_errno(status);
369 		goto bail;
370 	}
371 
372 	memset(bg, 0, sb->s_blocksize);
373 	strcpy(bg->bg_signature, OCFS2_GROUP_DESC_SIGNATURE);
374 	bg->bg_generation = cpu_to_le32(osb->fs_generation);
375 	bg->bg_size = cpu_to_le16(ocfs2_group_bitmap_size(sb, 1,
376 						osb->s_feature_incompat));
377 	bg->bg_chain = cpu_to_le16(my_chain);
378 	bg->bg_next_group = cl->cl_recs[my_chain].c_blkno;
379 	bg->bg_parent_dinode = cpu_to_le64(OCFS2_I(alloc_inode)->ip_blkno);
380 	bg->bg_blkno = cpu_to_le64(group_blkno);
381 	if (group_clusters == le16_to_cpu(cl->cl_cpg))
382 		bg->bg_bits = cpu_to_le16(ocfs2_bits_per_group(cl));
383 	else
384 		ocfs2_bg_discontig_add_extent(osb, bg, cl, group_blkno,
385 					      group_clusters);
386 
387 	/* set the 1st bit in the bitmap to account for the descriptor block */
388 	ocfs2_set_bit(0, (unsigned long *)bg->bg_bitmap);
389 	bg->bg_free_bits_count = cpu_to_le16(le16_to_cpu(bg->bg_bits) - 1);
390 
391 	ocfs2_journal_dirty(handle, bg_bh);
392 
393 	/* There is no need to zero out or otherwise initialize the
394 	 * other blocks in a group - All valid FS metadata in a block
395 	 * group stores the superblock fs_generation value at
396 	 * allocation time. */
397 
398 bail:
399 	if (status)
400 		mlog_errno(status);
401 	return status;
402 }
403 
ocfs2_find_smallest_chain(struct ocfs2_chain_list * cl)404 static inline u16 ocfs2_find_smallest_chain(struct ocfs2_chain_list *cl)
405 {
406 	u16 curr, best;
407 
408 	best = curr = 0;
409 	while (curr < le16_to_cpu(cl->cl_count)) {
410 		if (le32_to_cpu(cl->cl_recs[best].c_total) >
411 		    le32_to_cpu(cl->cl_recs[curr].c_total))
412 			best = curr;
413 		curr++;
414 	}
415 	return best;
416 }
417 
418 static struct buffer_head *
ocfs2_block_group_alloc_contig(struct ocfs2_super * osb,handle_t * handle,struct inode * alloc_inode,struct ocfs2_alloc_context * ac,struct ocfs2_chain_list * cl)419 ocfs2_block_group_alloc_contig(struct ocfs2_super *osb, handle_t *handle,
420 			       struct inode *alloc_inode,
421 			       struct ocfs2_alloc_context *ac,
422 			       struct ocfs2_chain_list *cl)
423 {
424 	int status;
425 	u32 bit_off, num_bits;
426 	u64 bg_blkno;
427 	struct buffer_head *bg_bh;
428 	unsigned int alloc_rec = ocfs2_find_smallest_chain(cl);
429 
430 	status = ocfs2_claim_clusters(handle, ac,
431 				      le16_to_cpu(cl->cl_cpg), &bit_off,
432 				      &num_bits);
433 	if (status < 0) {
434 		if (status != -ENOSPC)
435 			mlog_errno(status);
436 		goto bail;
437 	}
438 
439 	/* setup the group */
440 	bg_blkno = ocfs2_clusters_to_blocks(osb->sb, bit_off);
441 	trace_ocfs2_block_group_alloc_contig(
442 	     (unsigned long long)bg_blkno, alloc_rec);
443 
444 	bg_bh = sb_getblk(osb->sb, bg_blkno);
445 	if (!bg_bh) {
446 		status = -ENOMEM;
447 		mlog_errno(status);
448 		goto bail;
449 	}
450 	ocfs2_set_new_buffer_uptodate(INODE_CACHE(alloc_inode), bg_bh);
451 
452 	status = ocfs2_block_group_fill(handle, alloc_inode, bg_bh,
453 					bg_blkno, num_bits, alloc_rec, cl);
454 	if (status < 0) {
455 		brelse(bg_bh);
456 		mlog_errno(status);
457 	}
458 
459 bail:
460 	return status ? ERR_PTR(status) : bg_bh;
461 }
462 
ocfs2_block_group_claim_bits(struct ocfs2_super * osb,handle_t * handle,struct ocfs2_alloc_context * ac,unsigned int min_bits,u32 * bit_off,u32 * num_bits)463 static int ocfs2_block_group_claim_bits(struct ocfs2_super *osb,
464 					handle_t *handle,
465 					struct ocfs2_alloc_context *ac,
466 					unsigned int min_bits,
467 					u32 *bit_off, u32 *num_bits)
468 {
469 	int status = 0;
470 
471 	while (min_bits) {
472 		status = ocfs2_claim_clusters(handle, ac, min_bits,
473 					      bit_off, num_bits);
474 		if (status != -ENOSPC)
475 			break;
476 
477 		min_bits >>= 1;
478 	}
479 
480 	return status;
481 }
482 
ocfs2_block_group_grow_discontig(handle_t * handle,struct inode * alloc_inode,struct buffer_head * bg_bh,struct ocfs2_alloc_context * ac,struct ocfs2_chain_list * cl,unsigned int min_bits)483 static int ocfs2_block_group_grow_discontig(handle_t *handle,
484 					    struct inode *alloc_inode,
485 					    struct buffer_head *bg_bh,
486 					    struct ocfs2_alloc_context *ac,
487 					    struct ocfs2_chain_list *cl,
488 					    unsigned int min_bits)
489 {
490 	int status;
491 	struct ocfs2_super *osb = OCFS2_SB(alloc_inode->i_sb);
492 	struct ocfs2_group_desc *bg =
493 		(struct ocfs2_group_desc *)bg_bh->b_data;
494 	unsigned int needed = le16_to_cpu(cl->cl_cpg) -
495 			 le16_to_cpu(bg->bg_bits) / le16_to_cpu(cl->cl_bpc);
496 	u32 p_cpos, clusters;
497 	u64 p_blkno;
498 	struct ocfs2_extent_list *el = &bg->bg_list;
499 
500 	status = ocfs2_journal_access_gd(handle,
501 					 INODE_CACHE(alloc_inode),
502 					 bg_bh,
503 					 OCFS2_JOURNAL_ACCESS_CREATE);
504 	if (status < 0) {
505 		mlog_errno(status);
506 		goto bail;
507 	}
508 
509 	while ((needed > 0) && (le16_to_cpu(el->l_next_free_rec) <
510 				le16_to_cpu(el->l_count))) {
511 		if (min_bits > needed)
512 			min_bits = needed;
513 		status = ocfs2_block_group_claim_bits(osb, handle, ac,
514 						      min_bits, &p_cpos,
515 						      &clusters);
516 		if (status < 0) {
517 			if (status != -ENOSPC)
518 				mlog_errno(status);
519 			goto bail;
520 		}
521 		p_blkno = ocfs2_clusters_to_blocks(osb->sb, p_cpos);
522 		ocfs2_bg_discontig_add_extent(osb, bg, cl, p_blkno,
523 					      clusters);
524 
525 		min_bits = clusters;
526 		needed = le16_to_cpu(cl->cl_cpg) -
527 			 le16_to_cpu(bg->bg_bits) / le16_to_cpu(cl->cl_bpc);
528 	}
529 
530 	if (needed > 0) {
531 		/*
532 		 * We have used up all the extent rec but can't fill up
533 		 * the cpg. So bail out.
534 		 */
535 		status = -ENOSPC;
536 		goto bail;
537 	}
538 
539 	ocfs2_journal_dirty(handle, bg_bh);
540 
541 bail:
542 	return status;
543 }
544 
ocfs2_bg_alloc_cleanup(handle_t * handle,struct ocfs2_alloc_context * cluster_ac,struct inode * alloc_inode,struct buffer_head * bg_bh)545 static void ocfs2_bg_alloc_cleanup(handle_t *handle,
546 				   struct ocfs2_alloc_context *cluster_ac,
547 				   struct inode *alloc_inode,
548 				   struct buffer_head *bg_bh)
549 {
550 	int i, ret;
551 	struct ocfs2_group_desc *bg;
552 	struct ocfs2_extent_list *el;
553 	struct ocfs2_extent_rec *rec;
554 
555 	if (!bg_bh)
556 		return;
557 
558 	bg = (struct ocfs2_group_desc *)bg_bh->b_data;
559 	el = &bg->bg_list;
560 	for (i = 0; i < le16_to_cpu(el->l_next_free_rec); i++) {
561 		rec = &el->l_recs[i];
562 		ret = ocfs2_free_clusters(handle, cluster_ac->ac_inode,
563 					  cluster_ac->ac_bh,
564 					  le64_to_cpu(rec->e_blkno),
565 					  le16_to_cpu(rec->e_leaf_clusters));
566 		if (ret)
567 			mlog_errno(ret);
568 		/* Try all the clusters to free */
569 	}
570 
571 	ocfs2_remove_from_cache(INODE_CACHE(alloc_inode), bg_bh);
572 	brelse(bg_bh);
573 }
574 
575 static struct buffer_head *
ocfs2_block_group_alloc_discontig(handle_t * handle,struct inode * alloc_inode,struct ocfs2_alloc_context * ac,struct ocfs2_chain_list * cl)576 ocfs2_block_group_alloc_discontig(handle_t *handle,
577 				  struct inode *alloc_inode,
578 				  struct ocfs2_alloc_context *ac,
579 				  struct ocfs2_chain_list *cl)
580 {
581 	int status;
582 	u32 bit_off, num_bits;
583 	u64 bg_blkno;
584 	unsigned int min_bits = le16_to_cpu(cl->cl_cpg) >> 1;
585 	struct buffer_head *bg_bh = NULL;
586 	unsigned int alloc_rec = ocfs2_find_smallest_chain(cl);
587 	struct ocfs2_super *osb = OCFS2_SB(alloc_inode->i_sb);
588 
589 	if (!ocfs2_supports_discontig_bg(osb)) {
590 		status = -ENOSPC;
591 		goto bail;
592 	}
593 
594 	status = ocfs2_extend_trans(handle,
595 				    ocfs2_calc_bg_discontig_credits(osb->sb));
596 	if (status) {
597 		mlog_errno(status);
598 		goto bail;
599 	}
600 
601 	/*
602 	 * We're going to be grabbing from multiple cluster groups.
603 	 * We don't have enough credits to relink them all, and the
604 	 * cluster groups will be staying in cache for the duration of
605 	 * this operation.
606 	 */
607 	ac->ac_disable_chain_relink = 1;
608 
609 	/* Claim the first region */
610 	status = ocfs2_block_group_claim_bits(osb, handle, ac, min_bits,
611 					      &bit_off, &num_bits);
612 	if (status < 0) {
613 		if (status != -ENOSPC)
614 			mlog_errno(status);
615 		goto bail;
616 	}
617 	min_bits = num_bits;
618 
619 	/* setup the group */
620 	bg_blkno = ocfs2_clusters_to_blocks(osb->sb, bit_off);
621 	trace_ocfs2_block_group_alloc_discontig(
622 				(unsigned long long)bg_blkno, alloc_rec);
623 
624 	bg_bh = sb_getblk(osb->sb, bg_blkno);
625 	if (!bg_bh) {
626 		status = -ENOMEM;
627 		mlog_errno(status);
628 		goto bail;
629 	}
630 	ocfs2_set_new_buffer_uptodate(INODE_CACHE(alloc_inode), bg_bh);
631 
632 	status = ocfs2_block_group_fill(handle, alloc_inode, bg_bh,
633 					bg_blkno, num_bits, alloc_rec, cl);
634 	if (status < 0) {
635 		mlog_errno(status);
636 		goto bail;
637 	}
638 
639 	status = ocfs2_block_group_grow_discontig(handle, alloc_inode,
640 						  bg_bh, ac, cl, min_bits);
641 	if (status)
642 		mlog_errno(status);
643 
644 bail:
645 	if (status)
646 		ocfs2_bg_alloc_cleanup(handle, ac, alloc_inode, bg_bh);
647 	return status ? ERR_PTR(status) : bg_bh;
648 }
649 
650 /*
651  * We expect the block group allocator to already be locked.
652  */
ocfs2_block_group_alloc(struct ocfs2_super * osb,struct inode * alloc_inode,struct buffer_head * bh,u64 max_block,u64 * last_alloc_group,int flags)653 static int ocfs2_block_group_alloc(struct ocfs2_super *osb,
654 				   struct inode *alloc_inode,
655 				   struct buffer_head *bh,
656 				   u64 max_block,
657 				   u64 *last_alloc_group,
658 				   int flags)
659 {
660 	int status, credits;
661 	struct ocfs2_dinode *fe = (struct ocfs2_dinode *) bh->b_data;
662 	struct ocfs2_chain_list *cl;
663 	struct ocfs2_alloc_context *ac = NULL;
664 	handle_t *handle = NULL;
665 	u16 alloc_rec;
666 	struct buffer_head *bg_bh = NULL;
667 	struct ocfs2_group_desc *bg;
668 
669 	BUG_ON(ocfs2_is_cluster_bitmap(alloc_inode));
670 
671 	cl = &fe->id2.i_chain;
672 	status = ocfs2_reserve_clusters_with_limit(osb,
673 						   le16_to_cpu(cl->cl_cpg),
674 						   max_block, flags, &ac);
675 	if (status < 0) {
676 		if (status != -ENOSPC)
677 			mlog_errno(status);
678 		goto bail;
679 	}
680 
681 	credits = ocfs2_calc_group_alloc_credits(osb->sb,
682 						 le16_to_cpu(cl->cl_cpg));
683 	handle = ocfs2_start_trans(osb, credits);
684 	if (IS_ERR(handle)) {
685 		status = PTR_ERR(handle);
686 		handle = NULL;
687 		mlog_errno(status);
688 		goto bail;
689 	}
690 
691 	if (last_alloc_group && *last_alloc_group != 0) {
692 		trace_ocfs2_block_group_alloc(
693 				(unsigned long long)*last_alloc_group);
694 		ac->ac_last_group = *last_alloc_group;
695 	}
696 
697 	bg_bh = ocfs2_block_group_alloc_contig(osb, handle, alloc_inode,
698 					       ac, cl);
699 	if (IS_ERR(bg_bh) && (PTR_ERR(bg_bh) == -ENOSPC))
700 		bg_bh = ocfs2_block_group_alloc_discontig(handle,
701 							  alloc_inode,
702 							  ac, cl);
703 	if (IS_ERR(bg_bh)) {
704 		status = PTR_ERR(bg_bh);
705 		bg_bh = NULL;
706 		if (status != -ENOSPC)
707 			mlog_errno(status);
708 		goto bail;
709 	}
710 	bg = (struct ocfs2_group_desc *) bg_bh->b_data;
711 
712 	status = ocfs2_journal_access_di(handle, INODE_CACHE(alloc_inode),
713 					 bh, OCFS2_JOURNAL_ACCESS_WRITE);
714 	if (status < 0) {
715 		mlog_errno(status);
716 		goto bail;
717 	}
718 
719 	alloc_rec = le16_to_cpu(bg->bg_chain);
720 	le32_add_cpu(&cl->cl_recs[alloc_rec].c_free,
721 		     le16_to_cpu(bg->bg_free_bits_count));
722 	le32_add_cpu(&cl->cl_recs[alloc_rec].c_total,
723 		     le16_to_cpu(bg->bg_bits));
724 	cl->cl_recs[alloc_rec].c_blkno = bg->bg_blkno;
725 	if (le16_to_cpu(cl->cl_next_free_rec) < le16_to_cpu(cl->cl_count))
726 		le16_add_cpu(&cl->cl_next_free_rec, 1);
727 
728 	le32_add_cpu(&fe->id1.bitmap1.i_used, le16_to_cpu(bg->bg_bits) -
729 					le16_to_cpu(bg->bg_free_bits_count));
730 	le32_add_cpu(&fe->id1.bitmap1.i_total, le16_to_cpu(bg->bg_bits));
731 	le32_add_cpu(&fe->i_clusters, le16_to_cpu(cl->cl_cpg));
732 
733 	ocfs2_journal_dirty(handle, bh);
734 
735 	spin_lock(&OCFS2_I(alloc_inode)->ip_lock);
736 	OCFS2_I(alloc_inode)->ip_clusters = le32_to_cpu(fe->i_clusters);
737 	fe->i_size = cpu_to_le64(ocfs2_clusters_to_bytes(alloc_inode->i_sb,
738 					     le32_to_cpu(fe->i_clusters)));
739 	spin_unlock(&OCFS2_I(alloc_inode)->ip_lock);
740 	i_size_write(alloc_inode, le64_to_cpu(fe->i_size));
741 	alloc_inode->i_blocks = ocfs2_inode_sector_count(alloc_inode);
742 	ocfs2_update_inode_fsync_trans(handle, alloc_inode, 0);
743 
744 	status = 0;
745 
746 	/* save the new last alloc group so that the caller can cache it. */
747 	if (last_alloc_group)
748 		*last_alloc_group = ac->ac_last_group;
749 
750 bail:
751 	if (handle)
752 		ocfs2_commit_trans(osb, handle);
753 
754 	if (ac)
755 		ocfs2_free_alloc_context(ac);
756 
757 	brelse(bg_bh);
758 
759 	if (status)
760 		mlog_errno(status);
761 	return status;
762 }
763 
ocfs2_reserve_suballoc_bits(struct ocfs2_super * osb,struct ocfs2_alloc_context * ac,int type,u32 slot,u64 * last_alloc_group,int flags)764 static int ocfs2_reserve_suballoc_bits(struct ocfs2_super *osb,
765 				       struct ocfs2_alloc_context *ac,
766 				       int type,
767 				       u32 slot,
768 				       u64 *last_alloc_group,
769 				       int flags)
770 {
771 	int status;
772 	u32 bits_wanted = ac->ac_bits_wanted;
773 	struct inode *alloc_inode;
774 	struct buffer_head *bh = NULL;
775 	struct ocfs2_dinode *fe;
776 	u32 free_bits;
777 
778 	alloc_inode = ocfs2_get_system_file_inode(osb, type, slot);
779 	if (!alloc_inode) {
780 		mlog_errno(-EINVAL);
781 		return -EINVAL;
782 	}
783 
784 	inode_lock(alloc_inode);
785 
786 	status = ocfs2_inode_lock(alloc_inode, &bh, 1);
787 	if (status < 0) {
788 		inode_unlock(alloc_inode);
789 		iput(alloc_inode);
790 
791 		mlog_errno(status);
792 		return status;
793 	}
794 
795 	ac->ac_inode = alloc_inode;
796 	ac->ac_alloc_slot = slot;
797 
798 	fe = (struct ocfs2_dinode *) bh->b_data;
799 
800 	/* The bh was validated by the inode read inside
801 	 * ocfs2_inode_lock().  Any corruption is a code bug. */
802 	BUG_ON(!OCFS2_IS_VALID_DINODE(fe));
803 
804 	if (!(fe->i_flags & cpu_to_le32(OCFS2_CHAIN_FL))) {
805 		status = ocfs2_error(alloc_inode->i_sb,
806 				     "Invalid chain allocator %llu\n",
807 				     (unsigned long long)le64_to_cpu(fe->i_blkno));
808 		goto bail;
809 	}
810 
811 	free_bits = le32_to_cpu(fe->id1.bitmap1.i_total) -
812 		le32_to_cpu(fe->id1.bitmap1.i_used);
813 
814 	if (bits_wanted > free_bits) {
815 		/* cluster bitmap never grows */
816 		if (ocfs2_is_cluster_bitmap(alloc_inode)) {
817 			trace_ocfs2_reserve_suballoc_bits_nospc(bits_wanted,
818 								free_bits);
819 			status = -ENOSPC;
820 			goto bail;
821 		}
822 
823 		if (!(flags & ALLOC_NEW_GROUP)) {
824 			trace_ocfs2_reserve_suballoc_bits_no_new_group(
825 						slot, bits_wanted, free_bits);
826 			status = -ENOSPC;
827 			goto bail;
828 		}
829 
830 		status = ocfs2_block_group_alloc(osb, alloc_inode, bh,
831 						 ac->ac_max_block,
832 						 last_alloc_group, flags);
833 		if (status < 0) {
834 			if (status != -ENOSPC)
835 				mlog_errno(status);
836 			goto bail;
837 		}
838 		atomic_inc(&osb->alloc_stats.bg_extends);
839 
840 		/* You should never ask for this much metadata */
841 		BUG_ON(bits_wanted >
842 		       (le32_to_cpu(fe->id1.bitmap1.i_total)
843 			- le32_to_cpu(fe->id1.bitmap1.i_used)));
844 	}
845 
846 	get_bh(bh);
847 	ac->ac_bh = bh;
848 bail:
849 	brelse(bh);
850 
851 	if (status)
852 		mlog_errno(status);
853 	return status;
854 }
855 
ocfs2_init_inode_steal_slot(struct ocfs2_super * osb)856 static void ocfs2_init_inode_steal_slot(struct ocfs2_super *osb)
857 {
858 	spin_lock(&osb->osb_lock);
859 	osb->s_inode_steal_slot = OCFS2_INVALID_SLOT;
860 	spin_unlock(&osb->osb_lock);
861 	atomic_set(&osb->s_num_inodes_stolen, 0);
862 }
863 
ocfs2_init_meta_steal_slot(struct ocfs2_super * osb)864 static void ocfs2_init_meta_steal_slot(struct ocfs2_super *osb)
865 {
866 	spin_lock(&osb->osb_lock);
867 	osb->s_meta_steal_slot = OCFS2_INVALID_SLOT;
868 	spin_unlock(&osb->osb_lock);
869 	atomic_set(&osb->s_num_meta_stolen, 0);
870 }
871 
ocfs2_init_steal_slots(struct ocfs2_super * osb)872 void ocfs2_init_steal_slots(struct ocfs2_super *osb)
873 {
874 	ocfs2_init_inode_steal_slot(osb);
875 	ocfs2_init_meta_steal_slot(osb);
876 }
877 
__ocfs2_set_steal_slot(struct ocfs2_super * osb,int slot,int type)878 static void __ocfs2_set_steal_slot(struct ocfs2_super *osb, int slot, int type)
879 {
880 	spin_lock(&osb->osb_lock);
881 	if (type == INODE_ALLOC_SYSTEM_INODE)
882 		osb->s_inode_steal_slot = slot;
883 	else if (type == EXTENT_ALLOC_SYSTEM_INODE)
884 		osb->s_meta_steal_slot = slot;
885 	spin_unlock(&osb->osb_lock);
886 }
887 
__ocfs2_get_steal_slot(struct ocfs2_super * osb,int type)888 static int __ocfs2_get_steal_slot(struct ocfs2_super *osb, int type)
889 {
890 	int slot = OCFS2_INVALID_SLOT;
891 
892 	spin_lock(&osb->osb_lock);
893 	if (type == INODE_ALLOC_SYSTEM_INODE)
894 		slot = osb->s_inode_steal_slot;
895 	else if (type == EXTENT_ALLOC_SYSTEM_INODE)
896 		slot = osb->s_meta_steal_slot;
897 	spin_unlock(&osb->osb_lock);
898 
899 	return slot;
900 }
901 
ocfs2_get_inode_steal_slot(struct ocfs2_super * osb)902 static int ocfs2_get_inode_steal_slot(struct ocfs2_super *osb)
903 {
904 	return __ocfs2_get_steal_slot(osb, INODE_ALLOC_SYSTEM_INODE);
905 }
906 
ocfs2_get_meta_steal_slot(struct ocfs2_super * osb)907 static int ocfs2_get_meta_steal_slot(struct ocfs2_super *osb)
908 {
909 	return __ocfs2_get_steal_slot(osb, EXTENT_ALLOC_SYSTEM_INODE);
910 }
911 
ocfs2_steal_resource(struct ocfs2_super * osb,struct ocfs2_alloc_context * ac,int type)912 static int ocfs2_steal_resource(struct ocfs2_super *osb,
913 				struct ocfs2_alloc_context *ac,
914 				int type)
915 {
916 	int i, status = -ENOSPC;
917 	int slot = __ocfs2_get_steal_slot(osb, type);
918 
919 	/* Start to steal resource from the first slot after ours. */
920 	if (slot == OCFS2_INVALID_SLOT)
921 		slot = osb->slot_num + 1;
922 
923 	for (i = 0; i < osb->max_slots; i++, slot++) {
924 		if (slot == osb->max_slots)
925 			slot = 0;
926 
927 		if (slot == osb->slot_num)
928 			continue;
929 
930 		status = ocfs2_reserve_suballoc_bits(osb, ac,
931 						     type,
932 						     (u32)slot, NULL,
933 						     NOT_ALLOC_NEW_GROUP);
934 		if (status >= 0) {
935 			__ocfs2_set_steal_slot(osb, slot, type);
936 			break;
937 		}
938 
939 		ocfs2_free_ac_resource(ac);
940 	}
941 
942 	return status;
943 }
944 
ocfs2_steal_inode(struct ocfs2_super * osb,struct ocfs2_alloc_context * ac)945 static int ocfs2_steal_inode(struct ocfs2_super *osb,
946 			     struct ocfs2_alloc_context *ac)
947 {
948 	return ocfs2_steal_resource(osb, ac, INODE_ALLOC_SYSTEM_INODE);
949 }
950 
ocfs2_steal_meta(struct ocfs2_super * osb,struct ocfs2_alloc_context * ac)951 static int ocfs2_steal_meta(struct ocfs2_super *osb,
952 			    struct ocfs2_alloc_context *ac)
953 {
954 	return ocfs2_steal_resource(osb, ac, EXTENT_ALLOC_SYSTEM_INODE);
955 }
956 
ocfs2_reserve_new_metadata_blocks(struct ocfs2_super * osb,int blocks,struct ocfs2_alloc_context ** ac)957 int ocfs2_reserve_new_metadata_blocks(struct ocfs2_super *osb,
958 				      int blocks,
959 				      struct ocfs2_alloc_context **ac)
960 {
961 	int status;
962 	int slot = ocfs2_get_meta_steal_slot(osb);
963 
964 	*ac = kzalloc(sizeof(struct ocfs2_alloc_context), GFP_KERNEL);
965 	if (!(*ac)) {
966 		status = -ENOMEM;
967 		mlog_errno(status);
968 		goto bail;
969 	}
970 
971 	(*ac)->ac_bits_wanted = blocks;
972 	(*ac)->ac_which = OCFS2_AC_USE_META;
973 	(*ac)->ac_group_search = ocfs2_block_group_search;
974 
975 	if (slot != OCFS2_INVALID_SLOT &&
976 		atomic_read(&osb->s_num_meta_stolen) < OCFS2_MAX_TO_STEAL)
977 		goto extent_steal;
978 
979 	atomic_set(&osb->s_num_meta_stolen, 0);
980 	status = ocfs2_reserve_suballoc_bits(osb, (*ac),
981 					     EXTENT_ALLOC_SYSTEM_INODE,
982 					     (u32)osb->slot_num, NULL,
983 					     ALLOC_GROUPS_FROM_GLOBAL|ALLOC_NEW_GROUP);
984 
985 
986 	if (status >= 0) {
987 		status = 0;
988 		if (slot != OCFS2_INVALID_SLOT)
989 			ocfs2_init_meta_steal_slot(osb);
990 		goto bail;
991 	} else if (status < 0 && status != -ENOSPC) {
992 		mlog_errno(status);
993 		goto bail;
994 	}
995 
996 	ocfs2_free_ac_resource(*ac);
997 
998 extent_steal:
999 	status = ocfs2_steal_meta(osb, *ac);
1000 	atomic_inc(&osb->s_num_meta_stolen);
1001 	if (status < 0) {
1002 		if (status != -ENOSPC)
1003 			mlog_errno(status);
1004 		goto bail;
1005 	}
1006 
1007 	status = 0;
1008 bail:
1009 	if ((status < 0) && *ac) {
1010 		ocfs2_free_alloc_context(*ac);
1011 		*ac = NULL;
1012 	}
1013 
1014 	if (status)
1015 		mlog_errno(status);
1016 	return status;
1017 }
1018 
ocfs2_reserve_new_metadata(struct ocfs2_super * osb,struct ocfs2_extent_list * root_el,struct ocfs2_alloc_context ** ac)1019 int ocfs2_reserve_new_metadata(struct ocfs2_super *osb,
1020 			       struct ocfs2_extent_list *root_el,
1021 			       struct ocfs2_alloc_context **ac)
1022 {
1023 	return ocfs2_reserve_new_metadata_blocks(osb,
1024 					ocfs2_extend_meta_needed(root_el),
1025 					ac);
1026 }
1027 
ocfs2_reserve_new_inode(struct ocfs2_super * osb,struct ocfs2_alloc_context ** ac)1028 int ocfs2_reserve_new_inode(struct ocfs2_super *osb,
1029 			    struct ocfs2_alloc_context **ac)
1030 {
1031 	int status;
1032 	int slot = ocfs2_get_inode_steal_slot(osb);
1033 	u64 alloc_group;
1034 
1035 	*ac = kzalloc(sizeof(struct ocfs2_alloc_context), GFP_KERNEL);
1036 	if (!(*ac)) {
1037 		status = -ENOMEM;
1038 		mlog_errno(status);
1039 		goto bail;
1040 	}
1041 
1042 	(*ac)->ac_bits_wanted = 1;
1043 	(*ac)->ac_which = OCFS2_AC_USE_INODE;
1044 
1045 	(*ac)->ac_group_search = ocfs2_block_group_search;
1046 
1047 	/*
1048 	 * stat(2) can't handle i_ino > 32bits, so we tell the
1049 	 * lower levels not to allocate us a block group past that
1050 	 * limit.  The 'inode64' mount option avoids this behavior.
1051 	 */
1052 	if (!(osb->s_mount_opt & OCFS2_MOUNT_INODE64))
1053 		(*ac)->ac_max_block = (u32)~0U;
1054 
1055 	/*
1056 	 * slot is set when we successfully steal inode from other nodes.
1057 	 * It is reset in 3 places:
1058 	 * 1. when we flush the truncate log
1059 	 * 2. when we complete local alloc recovery.
1060 	 * 3. when we successfully allocate from our own slot.
1061 	 * After it is set, we will go on stealing inodes until we find the
1062 	 * need to check our slots to see whether there is some space for us.
1063 	 */
1064 	if (slot != OCFS2_INVALID_SLOT &&
1065 	    atomic_read(&osb->s_num_inodes_stolen) < OCFS2_MAX_TO_STEAL)
1066 		goto inode_steal;
1067 
1068 	atomic_set(&osb->s_num_inodes_stolen, 0);
1069 	alloc_group = osb->osb_inode_alloc_group;
1070 	status = ocfs2_reserve_suballoc_bits(osb, *ac,
1071 					     INODE_ALLOC_SYSTEM_INODE,
1072 					     (u32)osb->slot_num,
1073 					     &alloc_group,
1074 					     ALLOC_NEW_GROUP |
1075 					     ALLOC_GROUPS_FROM_GLOBAL);
1076 	if (status >= 0) {
1077 		status = 0;
1078 
1079 		spin_lock(&osb->osb_lock);
1080 		osb->osb_inode_alloc_group = alloc_group;
1081 		spin_unlock(&osb->osb_lock);
1082 		trace_ocfs2_reserve_new_inode_new_group(
1083 			(unsigned long long)alloc_group);
1084 
1085 		/*
1086 		 * Some inodes must be freed by us, so try to allocate
1087 		 * from our own next time.
1088 		 */
1089 		if (slot != OCFS2_INVALID_SLOT)
1090 			ocfs2_init_inode_steal_slot(osb);
1091 		goto bail;
1092 	} else if (status < 0 && status != -ENOSPC) {
1093 		mlog_errno(status);
1094 		goto bail;
1095 	}
1096 
1097 	ocfs2_free_ac_resource(*ac);
1098 
1099 inode_steal:
1100 	status = ocfs2_steal_inode(osb, *ac);
1101 	atomic_inc(&osb->s_num_inodes_stolen);
1102 	if (status < 0) {
1103 		if (status != -ENOSPC)
1104 			mlog_errno(status);
1105 		goto bail;
1106 	}
1107 
1108 	status = 0;
1109 bail:
1110 	if ((status < 0) && *ac) {
1111 		ocfs2_free_alloc_context(*ac);
1112 		*ac = NULL;
1113 	}
1114 
1115 	if (status)
1116 		mlog_errno(status);
1117 	return status;
1118 }
1119 
1120 /* local alloc code has to do the same thing, so rather than do this
1121  * twice.. */
ocfs2_reserve_cluster_bitmap_bits(struct ocfs2_super * osb,struct ocfs2_alloc_context * ac)1122 int ocfs2_reserve_cluster_bitmap_bits(struct ocfs2_super *osb,
1123 				      struct ocfs2_alloc_context *ac)
1124 {
1125 	int status;
1126 
1127 	ac->ac_which = OCFS2_AC_USE_MAIN;
1128 	ac->ac_group_search = ocfs2_cluster_group_search;
1129 
1130 	status = ocfs2_reserve_suballoc_bits(osb, ac,
1131 					     GLOBAL_BITMAP_SYSTEM_INODE,
1132 					     OCFS2_INVALID_SLOT, NULL,
1133 					     ALLOC_NEW_GROUP);
1134 	if (status < 0 && status != -ENOSPC)
1135 		mlog_errno(status);
1136 
1137 	return status;
1138 }
1139 
1140 /* Callers don't need to care which bitmap (local alloc or main) to
1141  * use so we figure it out for them, but unfortunately this clutters
1142  * things a bit. */
ocfs2_reserve_clusters_with_limit(struct ocfs2_super * osb,u32 bits_wanted,u64 max_block,int flags,struct ocfs2_alloc_context ** ac)1143 static int ocfs2_reserve_clusters_with_limit(struct ocfs2_super *osb,
1144 					     u32 bits_wanted, u64 max_block,
1145 					     int flags,
1146 					     struct ocfs2_alloc_context **ac)
1147 {
1148 	int status, ret = 0;
1149 	int retried = 0;
1150 
1151 	*ac = kzalloc(sizeof(struct ocfs2_alloc_context), GFP_KERNEL);
1152 	if (!(*ac)) {
1153 		status = -ENOMEM;
1154 		mlog_errno(status);
1155 		goto bail;
1156 	}
1157 
1158 	(*ac)->ac_bits_wanted = bits_wanted;
1159 	(*ac)->ac_max_block = max_block;
1160 
1161 	status = -ENOSPC;
1162 	if (!(flags & ALLOC_GROUPS_FROM_GLOBAL) &&
1163 	    ocfs2_alloc_should_use_local(osb, bits_wanted)) {
1164 		status = ocfs2_reserve_local_alloc_bits(osb,
1165 							bits_wanted,
1166 							*ac);
1167 		if ((status < 0) && (status != -ENOSPC)) {
1168 			mlog_errno(status);
1169 			goto bail;
1170 		}
1171 	}
1172 
1173 	if (status == -ENOSPC) {
1174 retry:
1175 		status = ocfs2_reserve_cluster_bitmap_bits(osb, *ac);
1176 		/* Retry if there is sufficient space cached in truncate log */
1177 		if (status == -ENOSPC && !retried) {
1178 			retried = 1;
1179 			ocfs2_inode_unlock((*ac)->ac_inode, 1);
1180 			inode_unlock((*ac)->ac_inode);
1181 
1182 			ret = ocfs2_try_to_free_truncate_log(osb, bits_wanted);
1183 			if (ret == 1) {
1184 				iput((*ac)->ac_inode);
1185 				(*ac)->ac_inode = NULL;
1186 				goto retry;
1187 			}
1188 
1189 			if (ret < 0)
1190 				mlog_errno(ret);
1191 
1192 			inode_lock((*ac)->ac_inode);
1193 			ret = ocfs2_inode_lock((*ac)->ac_inode, NULL, 1);
1194 			if (ret < 0) {
1195 				mlog_errno(ret);
1196 				inode_unlock((*ac)->ac_inode);
1197 				iput((*ac)->ac_inode);
1198 				(*ac)->ac_inode = NULL;
1199 				goto bail;
1200 			}
1201 		}
1202 		if (status < 0) {
1203 			if (status != -ENOSPC)
1204 				mlog_errno(status);
1205 			goto bail;
1206 		}
1207 	}
1208 
1209 	status = 0;
1210 bail:
1211 	if ((status < 0) && *ac) {
1212 		ocfs2_free_alloc_context(*ac);
1213 		*ac = NULL;
1214 	}
1215 
1216 	if (status)
1217 		mlog_errno(status);
1218 	return status;
1219 }
1220 
ocfs2_reserve_clusters(struct ocfs2_super * osb,u32 bits_wanted,struct ocfs2_alloc_context ** ac)1221 int ocfs2_reserve_clusters(struct ocfs2_super *osb,
1222 			   u32 bits_wanted,
1223 			   struct ocfs2_alloc_context **ac)
1224 {
1225 	return ocfs2_reserve_clusters_with_limit(osb, bits_wanted, 0,
1226 						 ALLOC_NEW_GROUP, ac);
1227 }
1228 
1229 /*
1230  * More or less lifted from ext3. I'll leave their description below:
1231  *
1232  * "For ext3 allocations, we must not reuse any blocks which are
1233  * allocated in the bitmap buffer's "last committed data" copy.  This
1234  * prevents deletes from freeing up the page for reuse until we have
1235  * committed the delete transaction.
1236  *
1237  * If we didn't do this, then deleting something and reallocating it as
1238  * data would allow the old block to be overwritten before the
1239  * transaction committed (because we force data to disk before commit).
1240  * This would lead to corruption if we crashed between overwriting the
1241  * data and committing the delete.
1242  *
1243  * @@@ We may want to make this allocation behaviour conditional on
1244  * data-writes at some point, and disable it for metadata allocations or
1245  * sync-data inodes."
1246  *
1247  * Note: OCFS2 already does this differently for metadata vs data
1248  * allocations, as those bitmaps are separate and undo access is never
1249  * called on a metadata group descriptor.
1250  */
ocfs2_test_bg_bit_allocatable(struct buffer_head * bg_bh,int nr)1251 static int ocfs2_test_bg_bit_allocatable(struct buffer_head *bg_bh,
1252 					 int nr)
1253 {
1254 	struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) bg_bh->b_data;
1255 	int ret;
1256 
1257 	if (ocfs2_test_bit(nr, (unsigned long *)bg->bg_bitmap))
1258 		return 0;
1259 
1260 	if (!buffer_jbd(bg_bh))
1261 		return 1;
1262 
1263 	jbd_lock_bh_state(bg_bh);
1264 	bg = (struct ocfs2_group_desc *) bh2jh(bg_bh)->b_committed_data;
1265 	if (bg)
1266 		ret = !ocfs2_test_bit(nr, (unsigned long *)bg->bg_bitmap);
1267 	else
1268 		ret = 1;
1269 	jbd_unlock_bh_state(bg_bh);
1270 
1271 	return ret;
1272 }
1273 
ocfs2_block_group_find_clear_bits(struct ocfs2_super * osb,struct buffer_head * bg_bh,unsigned int bits_wanted,unsigned int total_bits,struct ocfs2_suballoc_result * res)1274 static int ocfs2_block_group_find_clear_bits(struct ocfs2_super *osb,
1275 					     struct buffer_head *bg_bh,
1276 					     unsigned int bits_wanted,
1277 					     unsigned int total_bits,
1278 					     struct ocfs2_suballoc_result *res)
1279 {
1280 	void *bitmap;
1281 	u16 best_offset, best_size;
1282 	int offset, start, found, status = 0;
1283 	struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) bg_bh->b_data;
1284 
1285 	/* Callers got this descriptor from
1286 	 * ocfs2_read_group_descriptor().  Any corruption is a code bug. */
1287 	BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(bg));
1288 
1289 	found = start = best_offset = best_size = 0;
1290 	bitmap = bg->bg_bitmap;
1291 
1292 	while((offset = ocfs2_find_next_zero_bit(bitmap, total_bits, start)) != -1) {
1293 		if (offset == total_bits)
1294 			break;
1295 
1296 		if (!ocfs2_test_bg_bit_allocatable(bg_bh, offset)) {
1297 			/* We found a zero, but we can't use it as it
1298 			 * hasn't been put to disk yet! */
1299 			found = 0;
1300 			start = offset + 1;
1301 		} else if (offset == start) {
1302 			/* we found a zero */
1303 			found++;
1304 			/* move start to the next bit to test */
1305 			start++;
1306 		} else {
1307 			/* got a zero after some ones */
1308 			found = 1;
1309 			start = offset + 1;
1310 		}
1311 		if (found > best_size) {
1312 			best_size = found;
1313 			best_offset = start - found;
1314 		}
1315 		/* we got everything we needed */
1316 		if (found == bits_wanted) {
1317 			/* mlog(0, "Found it all!\n"); */
1318 			break;
1319 		}
1320 	}
1321 
1322 	if (best_size) {
1323 		res->sr_bit_offset = best_offset;
1324 		res->sr_bits = best_size;
1325 	} else {
1326 		status = -ENOSPC;
1327 		/* No error log here -- see the comment above
1328 		 * ocfs2_test_bg_bit_allocatable */
1329 	}
1330 
1331 	return status;
1332 }
1333 
ocfs2_block_group_set_bits(handle_t * handle,struct inode * alloc_inode,struct ocfs2_group_desc * bg,struct buffer_head * group_bh,unsigned int bit_off,unsigned int num_bits)1334 int ocfs2_block_group_set_bits(handle_t *handle,
1335 					     struct inode *alloc_inode,
1336 					     struct ocfs2_group_desc *bg,
1337 					     struct buffer_head *group_bh,
1338 					     unsigned int bit_off,
1339 					     unsigned int num_bits)
1340 {
1341 	int status;
1342 	void *bitmap = bg->bg_bitmap;
1343 	int journal_type = OCFS2_JOURNAL_ACCESS_WRITE;
1344 
1345 	/* All callers get the descriptor via
1346 	 * ocfs2_read_group_descriptor().  Any corruption is a code bug. */
1347 	BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(bg));
1348 	BUG_ON(le16_to_cpu(bg->bg_free_bits_count) < num_bits);
1349 
1350 	trace_ocfs2_block_group_set_bits(bit_off, num_bits);
1351 
1352 	if (ocfs2_is_cluster_bitmap(alloc_inode))
1353 		journal_type = OCFS2_JOURNAL_ACCESS_UNDO;
1354 
1355 	status = ocfs2_journal_access_gd(handle,
1356 					 INODE_CACHE(alloc_inode),
1357 					 group_bh,
1358 					 journal_type);
1359 	if (status < 0) {
1360 		mlog_errno(status);
1361 		goto bail;
1362 	}
1363 
1364 	le16_add_cpu(&bg->bg_free_bits_count, -num_bits);
1365 	if (le16_to_cpu(bg->bg_free_bits_count) > le16_to_cpu(bg->bg_bits)) {
1366 		return ocfs2_error(alloc_inode->i_sb, "Group descriptor # %llu has bit count %u but claims %u are freed. num_bits %d\n",
1367 				   (unsigned long long)le64_to_cpu(bg->bg_blkno),
1368 				   le16_to_cpu(bg->bg_bits),
1369 				   le16_to_cpu(bg->bg_free_bits_count),
1370 				   num_bits);
1371 	}
1372 	while(num_bits--)
1373 		ocfs2_set_bit(bit_off++, bitmap);
1374 
1375 	ocfs2_journal_dirty(handle, group_bh);
1376 
1377 bail:
1378 	return status;
1379 }
1380 
1381 /* find the one with the most empty bits */
ocfs2_find_victim_chain(struct ocfs2_chain_list * cl)1382 static inline u16 ocfs2_find_victim_chain(struct ocfs2_chain_list *cl)
1383 {
1384 	u16 curr, best;
1385 
1386 	BUG_ON(!cl->cl_next_free_rec);
1387 
1388 	best = curr = 0;
1389 	while (curr < le16_to_cpu(cl->cl_next_free_rec)) {
1390 		if (le32_to_cpu(cl->cl_recs[curr].c_free) >
1391 		    le32_to_cpu(cl->cl_recs[best].c_free))
1392 			best = curr;
1393 		curr++;
1394 	}
1395 
1396 	BUG_ON(best >= le16_to_cpu(cl->cl_next_free_rec));
1397 	return best;
1398 }
1399 
ocfs2_relink_block_group(handle_t * handle,struct inode * alloc_inode,struct buffer_head * fe_bh,struct buffer_head * bg_bh,struct buffer_head * prev_bg_bh,u16 chain)1400 static int ocfs2_relink_block_group(handle_t *handle,
1401 				    struct inode *alloc_inode,
1402 				    struct buffer_head *fe_bh,
1403 				    struct buffer_head *bg_bh,
1404 				    struct buffer_head *prev_bg_bh,
1405 				    u16 chain)
1406 {
1407 	int status;
1408 	/* there is a really tiny chance the journal calls could fail,
1409 	 * but we wouldn't want inconsistent blocks in *any* case. */
1410 	u64 bg_ptr, prev_bg_ptr;
1411 	struct ocfs2_dinode *fe = (struct ocfs2_dinode *) fe_bh->b_data;
1412 	struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) bg_bh->b_data;
1413 	struct ocfs2_group_desc *prev_bg = (struct ocfs2_group_desc *) prev_bg_bh->b_data;
1414 
1415 	/* The caller got these descriptors from
1416 	 * ocfs2_read_group_descriptor().  Any corruption is a code bug. */
1417 	BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(bg));
1418 	BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(prev_bg));
1419 
1420 	trace_ocfs2_relink_block_group(
1421 		(unsigned long long)le64_to_cpu(fe->i_blkno), chain,
1422 		(unsigned long long)le64_to_cpu(bg->bg_blkno),
1423 		(unsigned long long)le64_to_cpu(prev_bg->bg_blkno));
1424 
1425 	bg_ptr = le64_to_cpu(bg->bg_next_group);
1426 	prev_bg_ptr = le64_to_cpu(prev_bg->bg_next_group);
1427 
1428 	status = ocfs2_journal_access_gd(handle, INODE_CACHE(alloc_inode),
1429 					 prev_bg_bh,
1430 					 OCFS2_JOURNAL_ACCESS_WRITE);
1431 	if (status < 0)
1432 		goto out;
1433 
1434 	prev_bg->bg_next_group = bg->bg_next_group;
1435 	ocfs2_journal_dirty(handle, prev_bg_bh);
1436 
1437 	status = ocfs2_journal_access_gd(handle, INODE_CACHE(alloc_inode),
1438 					 bg_bh, OCFS2_JOURNAL_ACCESS_WRITE);
1439 	if (status < 0)
1440 		goto out_rollback_prev_bg;
1441 
1442 	bg->bg_next_group = fe->id2.i_chain.cl_recs[chain].c_blkno;
1443 	ocfs2_journal_dirty(handle, bg_bh);
1444 
1445 	status = ocfs2_journal_access_di(handle, INODE_CACHE(alloc_inode),
1446 					 fe_bh, OCFS2_JOURNAL_ACCESS_WRITE);
1447 	if (status < 0)
1448 		goto out_rollback_bg;
1449 
1450 	fe->id2.i_chain.cl_recs[chain].c_blkno = bg->bg_blkno;
1451 	ocfs2_journal_dirty(handle, fe_bh);
1452 
1453 out:
1454 	if (status < 0)
1455 		mlog_errno(status);
1456 	return status;
1457 
1458 out_rollback_bg:
1459 	bg->bg_next_group = cpu_to_le64(bg_ptr);
1460 out_rollback_prev_bg:
1461 	prev_bg->bg_next_group = cpu_to_le64(prev_bg_ptr);
1462 	goto out;
1463 }
1464 
ocfs2_block_group_reasonably_empty(struct ocfs2_group_desc * bg,u32 wanted)1465 static inline int ocfs2_block_group_reasonably_empty(struct ocfs2_group_desc *bg,
1466 						     u32 wanted)
1467 {
1468 	return le16_to_cpu(bg->bg_free_bits_count) > wanted;
1469 }
1470 
1471 /* return 0 on success, -ENOSPC to keep searching and any other < 0
1472  * value on error. */
ocfs2_cluster_group_search(struct inode * inode,struct buffer_head * group_bh,u32 bits_wanted,u32 min_bits,u64 max_block,struct ocfs2_suballoc_result * res)1473 static int ocfs2_cluster_group_search(struct inode *inode,
1474 				      struct buffer_head *group_bh,
1475 				      u32 bits_wanted, u32 min_bits,
1476 				      u64 max_block,
1477 				      struct ocfs2_suballoc_result *res)
1478 {
1479 	int search = -ENOSPC;
1480 	int ret;
1481 	u64 blkoff;
1482 	struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *) group_bh->b_data;
1483 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1484 	unsigned int max_bits, gd_cluster_off;
1485 
1486 	BUG_ON(!ocfs2_is_cluster_bitmap(inode));
1487 
1488 	if (gd->bg_free_bits_count) {
1489 		max_bits = le16_to_cpu(gd->bg_bits);
1490 
1491 		/* Tail groups in cluster bitmaps which aren't cpg
1492 		 * aligned are prone to partial extension by a failed
1493 		 * fs resize. If the file system resize never got to
1494 		 * update the dinode cluster count, then we don't want
1495 		 * to trust any clusters past it, regardless of what
1496 		 * the group descriptor says. */
1497 		gd_cluster_off = ocfs2_blocks_to_clusters(inode->i_sb,
1498 							  le64_to_cpu(gd->bg_blkno));
1499 		if ((gd_cluster_off + max_bits) >
1500 		    OCFS2_I(inode)->ip_clusters) {
1501 			max_bits = OCFS2_I(inode)->ip_clusters - gd_cluster_off;
1502 			trace_ocfs2_cluster_group_search_wrong_max_bits(
1503 				(unsigned long long)le64_to_cpu(gd->bg_blkno),
1504 				le16_to_cpu(gd->bg_bits),
1505 				OCFS2_I(inode)->ip_clusters, max_bits);
1506 		}
1507 
1508 		ret = ocfs2_block_group_find_clear_bits(osb,
1509 							group_bh, bits_wanted,
1510 							max_bits, res);
1511 		if (ret)
1512 			return ret;
1513 
1514 		if (max_block) {
1515 			blkoff = ocfs2_clusters_to_blocks(inode->i_sb,
1516 							  gd_cluster_off +
1517 							  res->sr_bit_offset +
1518 							  res->sr_bits);
1519 			trace_ocfs2_cluster_group_search_max_block(
1520 				(unsigned long long)blkoff,
1521 				(unsigned long long)max_block);
1522 			if (blkoff > max_block)
1523 				return -ENOSPC;
1524 		}
1525 
1526 		/* ocfs2_block_group_find_clear_bits() might
1527 		 * return success, but we still want to return
1528 		 * -ENOSPC unless it found the minimum number
1529 		 * of bits. */
1530 		if (min_bits <= res->sr_bits)
1531 			search = 0; /* success */
1532 		else if (res->sr_bits) {
1533 			/*
1534 			 * Don't show bits which we'll be returning
1535 			 * for allocation to the local alloc bitmap.
1536 			 */
1537 			ocfs2_local_alloc_seen_free_bits(osb, res->sr_bits);
1538 		}
1539 	}
1540 
1541 	return search;
1542 }
1543 
ocfs2_block_group_search(struct inode * inode,struct buffer_head * group_bh,u32 bits_wanted,u32 min_bits,u64 max_block,struct ocfs2_suballoc_result * res)1544 static int ocfs2_block_group_search(struct inode *inode,
1545 				    struct buffer_head *group_bh,
1546 				    u32 bits_wanted, u32 min_bits,
1547 				    u64 max_block,
1548 				    struct ocfs2_suballoc_result *res)
1549 {
1550 	int ret = -ENOSPC;
1551 	u64 blkoff;
1552 	struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) group_bh->b_data;
1553 
1554 	BUG_ON(min_bits != 1);
1555 	BUG_ON(ocfs2_is_cluster_bitmap(inode));
1556 
1557 	if (bg->bg_free_bits_count) {
1558 		ret = ocfs2_block_group_find_clear_bits(OCFS2_SB(inode->i_sb),
1559 							group_bh, bits_wanted,
1560 							le16_to_cpu(bg->bg_bits),
1561 							res);
1562 		if (!ret && max_block) {
1563 			blkoff = le64_to_cpu(bg->bg_blkno) +
1564 				res->sr_bit_offset + res->sr_bits;
1565 			trace_ocfs2_block_group_search_max_block(
1566 				(unsigned long long)blkoff,
1567 				(unsigned long long)max_block);
1568 			if (blkoff > max_block)
1569 				ret = -ENOSPC;
1570 		}
1571 	}
1572 
1573 	return ret;
1574 }
1575 
ocfs2_alloc_dinode_update_counts(struct inode * inode,handle_t * handle,struct buffer_head * di_bh,u32 num_bits,u16 chain)1576 int ocfs2_alloc_dinode_update_counts(struct inode *inode,
1577 				       handle_t *handle,
1578 				       struct buffer_head *di_bh,
1579 				       u32 num_bits,
1580 				       u16 chain)
1581 {
1582 	int ret;
1583 	u32 tmp_used;
1584 	struct ocfs2_dinode *di = (struct ocfs2_dinode *) di_bh->b_data;
1585 	struct ocfs2_chain_list *cl = (struct ocfs2_chain_list *) &di->id2.i_chain;
1586 
1587 	ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh,
1588 				      OCFS2_JOURNAL_ACCESS_WRITE);
1589 	if (ret < 0) {
1590 		mlog_errno(ret);
1591 		goto out;
1592 	}
1593 
1594 	tmp_used = le32_to_cpu(di->id1.bitmap1.i_used);
1595 	di->id1.bitmap1.i_used = cpu_to_le32(num_bits + tmp_used);
1596 	le32_add_cpu(&cl->cl_recs[chain].c_free, -num_bits);
1597 	ocfs2_journal_dirty(handle, di_bh);
1598 
1599 out:
1600 	return ret;
1601 }
1602 
ocfs2_rollback_alloc_dinode_counts(struct inode * inode,struct buffer_head * di_bh,u32 num_bits,u16 chain)1603 void ocfs2_rollback_alloc_dinode_counts(struct inode *inode,
1604 				       struct buffer_head *di_bh,
1605 				       u32 num_bits,
1606 				       u16 chain)
1607 {
1608 	u32 tmp_used;
1609 	struct ocfs2_dinode *di = (struct ocfs2_dinode *) di_bh->b_data;
1610 	struct ocfs2_chain_list *cl;
1611 
1612 	cl = (struct ocfs2_chain_list *)&di->id2.i_chain;
1613 	tmp_used = le32_to_cpu(di->id1.bitmap1.i_used);
1614 	di->id1.bitmap1.i_used = cpu_to_le32(tmp_used - num_bits);
1615 	le32_add_cpu(&cl->cl_recs[chain].c_free, num_bits);
1616 }
1617 
ocfs2_bg_discontig_fix_by_rec(struct ocfs2_suballoc_result * res,struct ocfs2_extent_rec * rec,struct ocfs2_chain_list * cl)1618 static int ocfs2_bg_discontig_fix_by_rec(struct ocfs2_suballoc_result *res,
1619 					 struct ocfs2_extent_rec *rec,
1620 					 struct ocfs2_chain_list *cl)
1621 {
1622 	unsigned int bpc = le16_to_cpu(cl->cl_bpc);
1623 	unsigned int bitoff = le32_to_cpu(rec->e_cpos) * bpc;
1624 	unsigned int bitcount = le16_to_cpu(rec->e_leaf_clusters) * bpc;
1625 
1626 	if (res->sr_bit_offset < bitoff)
1627 		return 0;
1628 	if (res->sr_bit_offset >= (bitoff + bitcount))
1629 		return 0;
1630 	res->sr_blkno = le64_to_cpu(rec->e_blkno) +
1631 		(res->sr_bit_offset - bitoff);
1632 	if ((res->sr_bit_offset + res->sr_bits) > (bitoff + bitcount))
1633 		res->sr_bits = (bitoff + bitcount) - res->sr_bit_offset;
1634 	return 1;
1635 }
1636 
ocfs2_bg_discontig_fix_result(struct ocfs2_alloc_context * ac,struct ocfs2_group_desc * bg,struct ocfs2_suballoc_result * res)1637 static void ocfs2_bg_discontig_fix_result(struct ocfs2_alloc_context *ac,
1638 					  struct ocfs2_group_desc *bg,
1639 					  struct ocfs2_suballoc_result *res)
1640 {
1641 	int i;
1642 	u64 bg_blkno = res->sr_bg_blkno;  /* Save off */
1643 	struct ocfs2_extent_rec *rec;
1644 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)ac->ac_bh->b_data;
1645 	struct ocfs2_chain_list *cl = &di->id2.i_chain;
1646 
1647 	if (ocfs2_is_cluster_bitmap(ac->ac_inode)) {
1648 		res->sr_blkno = 0;
1649 		return;
1650 	}
1651 
1652 	res->sr_blkno = res->sr_bg_blkno + res->sr_bit_offset;
1653 	res->sr_bg_blkno = 0;  /* Clear it for contig block groups */
1654 	if (!ocfs2_supports_discontig_bg(OCFS2_SB(ac->ac_inode->i_sb)) ||
1655 	    !bg->bg_list.l_next_free_rec)
1656 		return;
1657 
1658 	for (i = 0; i < le16_to_cpu(bg->bg_list.l_next_free_rec); i++) {
1659 		rec = &bg->bg_list.l_recs[i];
1660 		if (ocfs2_bg_discontig_fix_by_rec(res, rec, cl)) {
1661 			res->sr_bg_blkno = bg_blkno;  /* Restore */
1662 			break;
1663 		}
1664 	}
1665 }
1666 
ocfs2_search_one_group(struct ocfs2_alloc_context * ac,handle_t * handle,u32 bits_wanted,u32 min_bits,struct ocfs2_suballoc_result * res,u16 * bits_left)1667 static int ocfs2_search_one_group(struct ocfs2_alloc_context *ac,
1668 				  handle_t *handle,
1669 				  u32 bits_wanted,
1670 				  u32 min_bits,
1671 				  struct ocfs2_suballoc_result *res,
1672 				  u16 *bits_left)
1673 {
1674 	int ret;
1675 	struct buffer_head *group_bh = NULL;
1676 	struct ocfs2_group_desc *gd;
1677 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)ac->ac_bh->b_data;
1678 	struct inode *alloc_inode = ac->ac_inode;
1679 
1680 	ret = ocfs2_read_group_descriptor(alloc_inode, di,
1681 					  res->sr_bg_blkno, &group_bh);
1682 	if (ret < 0) {
1683 		mlog_errno(ret);
1684 		return ret;
1685 	}
1686 
1687 	gd = (struct ocfs2_group_desc *) group_bh->b_data;
1688 	ret = ac->ac_group_search(alloc_inode, group_bh, bits_wanted, min_bits,
1689 				  ac->ac_max_block, res);
1690 	if (ret < 0) {
1691 		if (ret != -ENOSPC)
1692 			mlog_errno(ret);
1693 		goto out;
1694 	}
1695 
1696 	if (!ret)
1697 		ocfs2_bg_discontig_fix_result(ac, gd, res);
1698 
1699 	/*
1700 	 * sr_bg_blkno might have been changed by
1701 	 * ocfs2_bg_discontig_fix_result
1702 	 */
1703 	res->sr_bg_stable_blkno = group_bh->b_blocknr;
1704 
1705 	if (ac->ac_find_loc_only)
1706 		goto out_loc_only;
1707 
1708 	ret = ocfs2_alloc_dinode_update_counts(alloc_inode, handle, ac->ac_bh,
1709 					       res->sr_bits,
1710 					       le16_to_cpu(gd->bg_chain));
1711 	if (ret < 0) {
1712 		mlog_errno(ret);
1713 		goto out;
1714 	}
1715 
1716 	ret = ocfs2_block_group_set_bits(handle, alloc_inode, gd, group_bh,
1717 					 res->sr_bit_offset, res->sr_bits);
1718 	if (ret < 0) {
1719 		ocfs2_rollback_alloc_dinode_counts(alloc_inode, ac->ac_bh,
1720 					       res->sr_bits,
1721 					       le16_to_cpu(gd->bg_chain));
1722 		mlog_errno(ret);
1723 	}
1724 
1725 out_loc_only:
1726 	*bits_left = le16_to_cpu(gd->bg_free_bits_count);
1727 
1728 out:
1729 	brelse(group_bh);
1730 
1731 	return ret;
1732 }
1733 
ocfs2_search_chain(struct ocfs2_alloc_context * ac,handle_t * handle,u32 bits_wanted,u32 min_bits,struct ocfs2_suballoc_result * res,u16 * bits_left)1734 static int ocfs2_search_chain(struct ocfs2_alloc_context *ac,
1735 			      handle_t *handle,
1736 			      u32 bits_wanted,
1737 			      u32 min_bits,
1738 			      struct ocfs2_suballoc_result *res,
1739 			      u16 *bits_left)
1740 {
1741 	int status;
1742 	u16 chain;
1743 	u64 next_group;
1744 	struct inode *alloc_inode = ac->ac_inode;
1745 	struct buffer_head *group_bh = NULL;
1746 	struct buffer_head *prev_group_bh = NULL;
1747 	struct ocfs2_dinode *fe = (struct ocfs2_dinode *) ac->ac_bh->b_data;
1748 	struct ocfs2_chain_list *cl = (struct ocfs2_chain_list *) &fe->id2.i_chain;
1749 	struct ocfs2_group_desc *bg;
1750 
1751 	chain = ac->ac_chain;
1752 	trace_ocfs2_search_chain_begin(
1753 		(unsigned long long)OCFS2_I(alloc_inode)->ip_blkno,
1754 		bits_wanted, chain);
1755 
1756 	status = ocfs2_read_group_descriptor(alloc_inode, fe,
1757 					     le64_to_cpu(cl->cl_recs[chain].c_blkno),
1758 					     &group_bh);
1759 	if (status < 0) {
1760 		mlog_errno(status);
1761 		goto bail;
1762 	}
1763 	bg = (struct ocfs2_group_desc *) group_bh->b_data;
1764 
1765 	status = -ENOSPC;
1766 	/* for now, the chain search is a bit simplistic. We just use
1767 	 * the 1st group with any empty bits. */
1768 	while ((status = ac->ac_group_search(alloc_inode, group_bh,
1769 					     bits_wanted, min_bits,
1770 					     ac->ac_max_block,
1771 					     res)) == -ENOSPC) {
1772 		if (!bg->bg_next_group)
1773 			break;
1774 
1775 		brelse(prev_group_bh);
1776 		prev_group_bh = NULL;
1777 
1778 		next_group = le64_to_cpu(bg->bg_next_group);
1779 		prev_group_bh = group_bh;
1780 		group_bh = NULL;
1781 		status = ocfs2_read_group_descriptor(alloc_inode, fe,
1782 						     next_group, &group_bh);
1783 		if (status < 0) {
1784 			mlog_errno(status);
1785 			goto bail;
1786 		}
1787 		bg = (struct ocfs2_group_desc *) group_bh->b_data;
1788 	}
1789 	if (status < 0) {
1790 		if (status != -ENOSPC)
1791 			mlog_errno(status);
1792 		goto bail;
1793 	}
1794 
1795 	trace_ocfs2_search_chain_succ(
1796 		(unsigned long long)le64_to_cpu(bg->bg_blkno), res->sr_bits);
1797 
1798 	res->sr_bg_blkno = le64_to_cpu(bg->bg_blkno);
1799 
1800 	BUG_ON(res->sr_bits == 0);
1801 	if (!status)
1802 		ocfs2_bg_discontig_fix_result(ac, bg, res);
1803 
1804 	/*
1805 	 * sr_bg_blkno might have been changed by
1806 	 * ocfs2_bg_discontig_fix_result
1807 	 */
1808 	res->sr_bg_stable_blkno = group_bh->b_blocknr;
1809 
1810 	/*
1811 	 * Keep track of previous block descriptor read. When
1812 	 * we find a target, if we have read more than X
1813 	 * number of descriptors, and the target is reasonably
1814 	 * empty, relink him to top of his chain.
1815 	 *
1816 	 * We've read 0 extra blocks and only send one more to
1817 	 * the transaction, yet the next guy to search has a
1818 	 * much easier time.
1819 	 *
1820 	 * Do this *after* figuring out how many bits we're taking out
1821 	 * of our target group.
1822 	 */
1823 	if (!ac->ac_disable_chain_relink &&
1824 	    (prev_group_bh) &&
1825 	    (ocfs2_block_group_reasonably_empty(bg, res->sr_bits))) {
1826 		status = ocfs2_relink_block_group(handle, alloc_inode,
1827 						  ac->ac_bh, group_bh,
1828 						  prev_group_bh, chain);
1829 		if (status < 0) {
1830 			mlog_errno(status);
1831 			goto bail;
1832 		}
1833 	}
1834 
1835 	if (ac->ac_find_loc_only)
1836 		goto out_loc_only;
1837 
1838 	status = ocfs2_alloc_dinode_update_counts(alloc_inode, handle,
1839 						  ac->ac_bh, res->sr_bits,
1840 						  chain);
1841 	if (status) {
1842 		mlog_errno(status);
1843 		goto bail;
1844 	}
1845 
1846 	status = ocfs2_block_group_set_bits(handle,
1847 					    alloc_inode,
1848 					    bg,
1849 					    group_bh,
1850 					    res->sr_bit_offset,
1851 					    res->sr_bits);
1852 	if (status < 0) {
1853 		ocfs2_rollback_alloc_dinode_counts(alloc_inode,
1854 					ac->ac_bh, res->sr_bits, chain);
1855 		mlog_errno(status);
1856 		goto bail;
1857 	}
1858 
1859 	trace_ocfs2_search_chain_end(
1860 			(unsigned long long)le64_to_cpu(fe->i_blkno),
1861 			res->sr_bits);
1862 
1863 out_loc_only:
1864 	*bits_left = le16_to_cpu(bg->bg_free_bits_count);
1865 bail:
1866 	brelse(group_bh);
1867 	brelse(prev_group_bh);
1868 
1869 	if (status)
1870 		mlog_errno(status);
1871 	return status;
1872 }
1873 
1874 /* will give out up to bits_wanted contiguous bits. */
ocfs2_claim_suballoc_bits(struct ocfs2_alloc_context * ac,handle_t * handle,u32 bits_wanted,u32 min_bits,struct ocfs2_suballoc_result * res)1875 static int ocfs2_claim_suballoc_bits(struct ocfs2_alloc_context *ac,
1876 				     handle_t *handle,
1877 				     u32 bits_wanted,
1878 				     u32 min_bits,
1879 				     struct ocfs2_suballoc_result *res)
1880 {
1881 	int status;
1882 	u16 victim, i;
1883 	u16 bits_left = 0;
1884 	u64 hint = ac->ac_last_group;
1885 	struct ocfs2_chain_list *cl;
1886 	struct ocfs2_dinode *fe;
1887 
1888 	BUG_ON(ac->ac_bits_given >= ac->ac_bits_wanted);
1889 	BUG_ON(bits_wanted > (ac->ac_bits_wanted - ac->ac_bits_given));
1890 	BUG_ON(!ac->ac_bh);
1891 
1892 	fe = (struct ocfs2_dinode *) ac->ac_bh->b_data;
1893 
1894 	/* The bh was validated by the inode read during
1895 	 * ocfs2_reserve_suballoc_bits().  Any corruption is a code bug. */
1896 	BUG_ON(!OCFS2_IS_VALID_DINODE(fe));
1897 
1898 	if (le32_to_cpu(fe->id1.bitmap1.i_used) >=
1899 	    le32_to_cpu(fe->id1.bitmap1.i_total)) {
1900 		status = ocfs2_error(ac->ac_inode->i_sb,
1901 				     "Chain allocator dinode %llu has %u used bits but only %u total\n",
1902 				     (unsigned long long)le64_to_cpu(fe->i_blkno),
1903 				     le32_to_cpu(fe->id1.bitmap1.i_used),
1904 				     le32_to_cpu(fe->id1.bitmap1.i_total));
1905 		goto bail;
1906 	}
1907 
1908 	res->sr_bg_blkno = hint;
1909 	if (res->sr_bg_blkno) {
1910 		/* Attempt to short-circuit the usual search mechanism
1911 		 * by jumping straight to the most recently used
1912 		 * allocation group. This helps us maintain some
1913 		 * contiguousness across allocations. */
1914 		status = ocfs2_search_one_group(ac, handle, bits_wanted,
1915 						min_bits, res, &bits_left);
1916 		if (!status)
1917 			goto set_hint;
1918 		if (status < 0 && status != -ENOSPC) {
1919 			mlog_errno(status);
1920 			goto bail;
1921 		}
1922 	}
1923 
1924 	cl = (struct ocfs2_chain_list *) &fe->id2.i_chain;
1925 
1926 	victim = ocfs2_find_victim_chain(cl);
1927 	ac->ac_chain = victim;
1928 
1929 	status = ocfs2_search_chain(ac, handle, bits_wanted, min_bits,
1930 				    res, &bits_left);
1931 	if (!status) {
1932 		if (ocfs2_is_cluster_bitmap(ac->ac_inode))
1933 			hint = res->sr_bg_blkno;
1934 		else
1935 			hint = ocfs2_group_from_res(res);
1936 		goto set_hint;
1937 	}
1938 	if (status < 0 && status != -ENOSPC) {
1939 		mlog_errno(status);
1940 		goto bail;
1941 	}
1942 
1943 	trace_ocfs2_claim_suballoc_bits(victim);
1944 
1945 	/* If we didn't pick a good victim, then just default to
1946 	 * searching each chain in order. Don't allow chain relinking
1947 	 * because we only calculate enough journal credits for one
1948 	 * relink per alloc. */
1949 	ac->ac_disable_chain_relink = 1;
1950 	for (i = 0; i < le16_to_cpu(cl->cl_next_free_rec); i ++) {
1951 		if (i == victim)
1952 			continue;
1953 		if (!cl->cl_recs[i].c_free)
1954 			continue;
1955 
1956 		ac->ac_chain = i;
1957 		status = ocfs2_search_chain(ac, handle, bits_wanted, min_bits,
1958 					    res, &bits_left);
1959 		if (!status) {
1960 			hint = ocfs2_group_from_res(res);
1961 			break;
1962 		}
1963 		if (status < 0 && status != -ENOSPC) {
1964 			mlog_errno(status);
1965 			goto bail;
1966 		}
1967 	}
1968 
1969 set_hint:
1970 	if (status != -ENOSPC) {
1971 		/* If the next search of this group is not likely to
1972 		 * yield a suitable extent, then we reset the last
1973 		 * group hint so as to not waste a disk read */
1974 		if (bits_left < min_bits)
1975 			ac->ac_last_group = 0;
1976 		else
1977 			ac->ac_last_group = hint;
1978 	}
1979 
1980 bail:
1981 	if (status)
1982 		mlog_errno(status);
1983 	return status;
1984 }
1985 
ocfs2_claim_metadata(handle_t * handle,struct ocfs2_alloc_context * ac,u32 bits_wanted,u64 * suballoc_loc,u16 * suballoc_bit_start,unsigned int * num_bits,u64 * blkno_start)1986 int ocfs2_claim_metadata(handle_t *handle,
1987 			 struct ocfs2_alloc_context *ac,
1988 			 u32 bits_wanted,
1989 			 u64 *suballoc_loc,
1990 			 u16 *suballoc_bit_start,
1991 			 unsigned int *num_bits,
1992 			 u64 *blkno_start)
1993 {
1994 	int status;
1995 	struct ocfs2_suballoc_result res = { .sr_blkno = 0, };
1996 
1997 	BUG_ON(!ac);
1998 	BUG_ON(ac->ac_bits_wanted < (ac->ac_bits_given + bits_wanted));
1999 	BUG_ON(ac->ac_which != OCFS2_AC_USE_META);
2000 
2001 	status = ocfs2_claim_suballoc_bits(ac,
2002 					   handle,
2003 					   bits_wanted,
2004 					   1,
2005 					   &res);
2006 	if (status < 0) {
2007 		mlog_errno(status);
2008 		goto bail;
2009 	}
2010 	atomic_inc(&OCFS2_SB(ac->ac_inode->i_sb)->alloc_stats.bg_allocs);
2011 
2012 	*suballoc_loc = res.sr_bg_blkno;
2013 	*suballoc_bit_start = res.sr_bit_offset;
2014 	*blkno_start = res.sr_blkno;
2015 	ac->ac_bits_given += res.sr_bits;
2016 	*num_bits = res.sr_bits;
2017 	status = 0;
2018 bail:
2019 	if (status)
2020 		mlog_errno(status);
2021 	return status;
2022 }
2023 
ocfs2_init_inode_ac_group(struct inode * dir,struct buffer_head * parent_di_bh,struct ocfs2_alloc_context * ac)2024 static void ocfs2_init_inode_ac_group(struct inode *dir,
2025 				      struct buffer_head *parent_di_bh,
2026 				      struct ocfs2_alloc_context *ac)
2027 {
2028 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)parent_di_bh->b_data;
2029 	/*
2030 	 * Try to allocate inodes from some specific group.
2031 	 *
2032 	 * If the parent dir has recorded the last group used in allocation,
2033 	 * cool, use it. Otherwise if we try to allocate new inode from the
2034 	 * same slot the parent dir belongs to, use the same chunk.
2035 	 *
2036 	 * We are very careful here to avoid the mistake of setting
2037 	 * ac_last_group to a group descriptor from a different (unlocked) slot.
2038 	 */
2039 	if (OCFS2_I(dir)->ip_last_used_group &&
2040 	    OCFS2_I(dir)->ip_last_used_slot == ac->ac_alloc_slot)
2041 		ac->ac_last_group = OCFS2_I(dir)->ip_last_used_group;
2042 	else if (le16_to_cpu(di->i_suballoc_slot) == ac->ac_alloc_slot) {
2043 		if (di->i_suballoc_loc)
2044 			ac->ac_last_group = le64_to_cpu(di->i_suballoc_loc);
2045 		else
2046 			ac->ac_last_group = ocfs2_which_suballoc_group(
2047 					le64_to_cpu(di->i_blkno),
2048 					le16_to_cpu(di->i_suballoc_bit));
2049 	}
2050 }
2051 
ocfs2_save_inode_ac_group(struct inode * dir,struct ocfs2_alloc_context * ac)2052 static inline void ocfs2_save_inode_ac_group(struct inode *dir,
2053 					     struct ocfs2_alloc_context *ac)
2054 {
2055 	OCFS2_I(dir)->ip_last_used_group = ac->ac_last_group;
2056 	OCFS2_I(dir)->ip_last_used_slot = ac->ac_alloc_slot;
2057 }
2058 
ocfs2_find_new_inode_loc(struct inode * dir,struct buffer_head * parent_fe_bh,struct ocfs2_alloc_context * ac,u64 * fe_blkno)2059 int ocfs2_find_new_inode_loc(struct inode *dir,
2060 			     struct buffer_head *parent_fe_bh,
2061 			     struct ocfs2_alloc_context *ac,
2062 			     u64 *fe_blkno)
2063 {
2064 	int ret;
2065 	handle_t *handle = NULL;
2066 	struct ocfs2_suballoc_result *res;
2067 
2068 	BUG_ON(!ac);
2069 	BUG_ON(ac->ac_bits_given != 0);
2070 	BUG_ON(ac->ac_bits_wanted != 1);
2071 	BUG_ON(ac->ac_which != OCFS2_AC_USE_INODE);
2072 
2073 	res = kzalloc(sizeof(*res), GFP_NOFS);
2074 	if (res == NULL) {
2075 		ret = -ENOMEM;
2076 		mlog_errno(ret);
2077 		goto out;
2078 	}
2079 
2080 	ocfs2_init_inode_ac_group(dir, parent_fe_bh, ac);
2081 
2082 	/*
2083 	 * The handle started here is for chain relink. Alternatively,
2084 	 * we could just disable relink for these calls.
2085 	 */
2086 	handle = ocfs2_start_trans(OCFS2_SB(dir->i_sb), OCFS2_SUBALLOC_ALLOC);
2087 	if (IS_ERR(handle)) {
2088 		ret = PTR_ERR(handle);
2089 		handle = NULL;
2090 		mlog_errno(ret);
2091 		goto out;
2092 	}
2093 
2094 	/*
2095 	 * This will instruct ocfs2_claim_suballoc_bits and
2096 	 * ocfs2_search_one_group to search but save actual allocation
2097 	 * for later.
2098 	 */
2099 	ac->ac_find_loc_only = 1;
2100 
2101 	ret = ocfs2_claim_suballoc_bits(ac, handle, 1, 1, res);
2102 	if (ret < 0) {
2103 		mlog_errno(ret);
2104 		goto out;
2105 	}
2106 
2107 	ac->ac_find_loc_priv = res;
2108 	*fe_blkno = res->sr_blkno;
2109 	ocfs2_update_inode_fsync_trans(handle, dir, 0);
2110 out:
2111 	if (handle)
2112 		ocfs2_commit_trans(OCFS2_SB(dir->i_sb), handle);
2113 
2114 	if (ret)
2115 		kfree(res);
2116 
2117 	return ret;
2118 }
2119 
ocfs2_claim_new_inode_at_loc(handle_t * handle,struct inode * dir,struct ocfs2_alloc_context * ac,u64 * suballoc_loc,u16 * suballoc_bit,u64 di_blkno)2120 int ocfs2_claim_new_inode_at_loc(handle_t *handle,
2121 				 struct inode *dir,
2122 				 struct ocfs2_alloc_context *ac,
2123 				 u64 *suballoc_loc,
2124 				 u16 *suballoc_bit,
2125 				 u64 di_blkno)
2126 {
2127 	int ret;
2128 	u16 chain;
2129 	struct ocfs2_suballoc_result *res = ac->ac_find_loc_priv;
2130 	struct buffer_head *bg_bh = NULL;
2131 	struct ocfs2_group_desc *bg;
2132 	struct ocfs2_dinode *di = (struct ocfs2_dinode *) ac->ac_bh->b_data;
2133 
2134 	/*
2135 	 * Since di_blkno is being passed back in, we check for any
2136 	 * inconsistencies which may have happened between
2137 	 * calls. These are code bugs as di_blkno is not expected to
2138 	 * change once returned from ocfs2_find_new_inode_loc()
2139 	 */
2140 	BUG_ON(res->sr_blkno != di_blkno);
2141 
2142 	ret = ocfs2_read_group_descriptor(ac->ac_inode, di,
2143 					  res->sr_bg_stable_blkno, &bg_bh);
2144 	if (ret) {
2145 		mlog_errno(ret);
2146 		goto out;
2147 	}
2148 
2149 	bg = (struct ocfs2_group_desc *) bg_bh->b_data;
2150 	chain = le16_to_cpu(bg->bg_chain);
2151 
2152 	ret = ocfs2_alloc_dinode_update_counts(ac->ac_inode, handle,
2153 					       ac->ac_bh, res->sr_bits,
2154 					       chain);
2155 	if (ret) {
2156 		mlog_errno(ret);
2157 		goto out;
2158 	}
2159 
2160 	ret = ocfs2_block_group_set_bits(handle,
2161 					 ac->ac_inode,
2162 					 bg,
2163 					 bg_bh,
2164 					 res->sr_bit_offset,
2165 					 res->sr_bits);
2166 	if (ret < 0) {
2167 		ocfs2_rollback_alloc_dinode_counts(ac->ac_inode,
2168 					       ac->ac_bh, res->sr_bits, chain);
2169 		mlog_errno(ret);
2170 		goto out;
2171 	}
2172 
2173 	trace_ocfs2_claim_new_inode_at_loc((unsigned long long)di_blkno,
2174 					   res->sr_bits);
2175 
2176 	atomic_inc(&OCFS2_SB(ac->ac_inode->i_sb)->alloc_stats.bg_allocs);
2177 
2178 	BUG_ON(res->sr_bits != 1);
2179 
2180 	*suballoc_loc = res->sr_bg_blkno;
2181 	*suballoc_bit = res->sr_bit_offset;
2182 	ac->ac_bits_given++;
2183 	ocfs2_save_inode_ac_group(dir, ac);
2184 
2185 out:
2186 	brelse(bg_bh);
2187 
2188 	return ret;
2189 }
2190 
ocfs2_claim_new_inode(handle_t * handle,struct inode * dir,struct buffer_head * parent_fe_bh,struct ocfs2_alloc_context * ac,u64 * suballoc_loc,u16 * suballoc_bit,u64 * fe_blkno)2191 int ocfs2_claim_new_inode(handle_t *handle,
2192 			  struct inode *dir,
2193 			  struct buffer_head *parent_fe_bh,
2194 			  struct ocfs2_alloc_context *ac,
2195 			  u64 *suballoc_loc,
2196 			  u16 *suballoc_bit,
2197 			  u64 *fe_blkno)
2198 {
2199 	int status;
2200 	struct ocfs2_suballoc_result res;
2201 
2202 	BUG_ON(!ac);
2203 	BUG_ON(ac->ac_bits_given != 0);
2204 	BUG_ON(ac->ac_bits_wanted != 1);
2205 	BUG_ON(ac->ac_which != OCFS2_AC_USE_INODE);
2206 
2207 	ocfs2_init_inode_ac_group(dir, parent_fe_bh, ac);
2208 
2209 	status = ocfs2_claim_suballoc_bits(ac,
2210 					   handle,
2211 					   1,
2212 					   1,
2213 					   &res);
2214 	if (status < 0) {
2215 		mlog_errno(status);
2216 		goto bail;
2217 	}
2218 	atomic_inc(&OCFS2_SB(ac->ac_inode->i_sb)->alloc_stats.bg_allocs);
2219 
2220 	BUG_ON(res.sr_bits != 1);
2221 
2222 	*suballoc_loc = res.sr_bg_blkno;
2223 	*suballoc_bit = res.sr_bit_offset;
2224 	*fe_blkno = res.sr_blkno;
2225 	ac->ac_bits_given++;
2226 	ocfs2_save_inode_ac_group(dir, ac);
2227 	status = 0;
2228 bail:
2229 	if (status)
2230 		mlog_errno(status);
2231 	return status;
2232 }
2233 
2234 /* translate a group desc. blkno and it's bitmap offset into
2235  * disk cluster offset. */
ocfs2_desc_bitmap_to_cluster_off(struct inode * inode,u64 bg_blkno,u16 bg_bit_off)2236 static inline u32 ocfs2_desc_bitmap_to_cluster_off(struct inode *inode,
2237 						   u64 bg_blkno,
2238 						   u16 bg_bit_off)
2239 {
2240 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
2241 	u32 cluster = 0;
2242 
2243 	BUG_ON(!ocfs2_is_cluster_bitmap(inode));
2244 
2245 	if (bg_blkno != osb->first_cluster_group_blkno)
2246 		cluster = ocfs2_blocks_to_clusters(inode->i_sb, bg_blkno);
2247 	cluster += (u32) bg_bit_off;
2248 	return cluster;
2249 }
2250 
2251 /* given a cluster offset, calculate which block group it belongs to
2252  * and return that block offset. */
ocfs2_which_cluster_group(struct inode * inode,u32 cluster)2253 u64 ocfs2_which_cluster_group(struct inode *inode, u32 cluster)
2254 {
2255 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
2256 	u32 group_no;
2257 
2258 	BUG_ON(!ocfs2_is_cluster_bitmap(inode));
2259 
2260 	group_no = cluster / osb->bitmap_cpg;
2261 	if (!group_no)
2262 		return osb->first_cluster_group_blkno;
2263 	return ocfs2_clusters_to_blocks(inode->i_sb,
2264 					group_no * osb->bitmap_cpg);
2265 }
2266 
2267 /* given the block number of a cluster start, calculate which cluster
2268  * group and descriptor bitmap offset that corresponds to. */
ocfs2_block_to_cluster_group(struct inode * inode,u64 data_blkno,u64 * bg_blkno,u16 * bg_bit_off)2269 static inline void ocfs2_block_to_cluster_group(struct inode *inode,
2270 						u64 data_blkno,
2271 						u64 *bg_blkno,
2272 						u16 *bg_bit_off)
2273 {
2274 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
2275 	u32 data_cluster = ocfs2_blocks_to_clusters(osb->sb, data_blkno);
2276 
2277 	BUG_ON(!ocfs2_is_cluster_bitmap(inode));
2278 
2279 	*bg_blkno = ocfs2_which_cluster_group(inode,
2280 					      data_cluster);
2281 
2282 	if (*bg_blkno == osb->first_cluster_group_blkno)
2283 		*bg_bit_off = (u16) data_cluster;
2284 	else
2285 		*bg_bit_off = (u16) ocfs2_blocks_to_clusters(osb->sb,
2286 							     data_blkno - *bg_blkno);
2287 }
2288 
2289 /*
2290  * min_bits - minimum contiguous chunk from this total allocation we
2291  * can handle. set to what we asked for originally for a full
2292  * contig. allocation, set to '1' to indicate we can deal with extents
2293  * of any size.
2294  */
__ocfs2_claim_clusters(handle_t * handle,struct ocfs2_alloc_context * ac,u32 min_clusters,u32 max_clusters,u32 * cluster_start,u32 * num_clusters)2295 int __ocfs2_claim_clusters(handle_t *handle,
2296 			   struct ocfs2_alloc_context *ac,
2297 			   u32 min_clusters,
2298 			   u32 max_clusters,
2299 			   u32 *cluster_start,
2300 			   u32 *num_clusters)
2301 {
2302 	int status;
2303 	unsigned int bits_wanted = max_clusters;
2304 	struct ocfs2_suballoc_result res = { .sr_blkno = 0, };
2305 	struct ocfs2_super *osb = OCFS2_SB(ac->ac_inode->i_sb);
2306 
2307 	BUG_ON(ac->ac_bits_given >= ac->ac_bits_wanted);
2308 
2309 	BUG_ON(ac->ac_which != OCFS2_AC_USE_LOCAL
2310 	       && ac->ac_which != OCFS2_AC_USE_MAIN);
2311 
2312 	if (ac->ac_which == OCFS2_AC_USE_LOCAL) {
2313 		WARN_ON(min_clusters > 1);
2314 
2315 		status = ocfs2_claim_local_alloc_bits(osb,
2316 						      handle,
2317 						      ac,
2318 						      bits_wanted,
2319 						      cluster_start,
2320 						      num_clusters);
2321 		if (!status)
2322 			atomic_inc(&osb->alloc_stats.local_data);
2323 	} else {
2324 		if (min_clusters > (osb->bitmap_cpg - 1)) {
2325 			/* The only paths asking for contiguousness
2326 			 * should know about this already. */
2327 			mlog(ML_ERROR, "minimum allocation requested %u exceeds "
2328 			     "group bitmap size %u!\n", min_clusters,
2329 			     osb->bitmap_cpg);
2330 			status = -ENOSPC;
2331 			goto bail;
2332 		}
2333 		/* clamp the current request down to a realistic size. */
2334 		if (bits_wanted > (osb->bitmap_cpg - 1))
2335 			bits_wanted = osb->bitmap_cpg - 1;
2336 
2337 		status = ocfs2_claim_suballoc_bits(ac,
2338 						   handle,
2339 						   bits_wanted,
2340 						   min_clusters,
2341 						   &res);
2342 		if (!status) {
2343 			BUG_ON(res.sr_blkno); /* cluster alloc can't set */
2344 			*cluster_start =
2345 				ocfs2_desc_bitmap_to_cluster_off(ac->ac_inode,
2346 								 res.sr_bg_blkno,
2347 								 res.sr_bit_offset);
2348 			atomic_inc(&osb->alloc_stats.bitmap_data);
2349 			*num_clusters = res.sr_bits;
2350 		}
2351 	}
2352 	if (status < 0) {
2353 		if (status != -ENOSPC)
2354 			mlog_errno(status);
2355 		goto bail;
2356 	}
2357 
2358 	ac->ac_bits_given += *num_clusters;
2359 
2360 bail:
2361 	if (status)
2362 		mlog_errno(status);
2363 	return status;
2364 }
2365 
ocfs2_claim_clusters(handle_t * handle,struct ocfs2_alloc_context * ac,u32 min_clusters,u32 * cluster_start,u32 * num_clusters)2366 int ocfs2_claim_clusters(handle_t *handle,
2367 			 struct ocfs2_alloc_context *ac,
2368 			 u32 min_clusters,
2369 			 u32 *cluster_start,
2370 			 u32 *num_clusters)
2371 {
2372 	unsigned int bits_wanted = ac->ac_bits_wanted - ac->ac_bits_given;
2373 
2374 	return __ocfs2_claim_clusters(handle, ac, min_clusters,
2375 				      bits_wanted, cluster_start, num_clusters);
2376 }
2377 
ocfs2_block_group_clear_bits(handle_t * handle,struct inode * alloc_inode,struct ocfs2_group_desc * bg,struct buffer_head * group_bh,unsigned int bit_off,unsigned int num_bits,void (* undo_fn)(unsigned int bit,unsigned long * bmap))2378 static int ocfs2_block_group_clear_bits(handle_t *handle,
2379 					struct inode *alloc_inode,
2380 					struct ocfs2_group_desc *bg,
2381 					struct buffer_head *group_bh,
2382 					unsigned int bit_off,
2383 					unsigned int num_bits,
2384 					void (*undo_fn)(unsigned int bit,
2385 							unsigned long *bmap))
2386 {
2387 	int status;
2388 	unsigned int tmp;
2389 	struct ocfs2_group_desc *undo_bg = NULL;
2390 
2391 	/* The caller got this descriptor from
2392 	 * ocfs2_read_group_descriptor().  Any corruption is a code bug. */
2393 	BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(bg));
2394 
2395 	trace_ocfs2_block_group_clear_bits(bit_off, num_bits);
2396 
2397 	BUG_ON(undo_fn && !ocfs2_is_cluster_bitmap(alloc_inode));
2398 	status = ocfs2_journal_access_gd(handle, INODE_CACHE(alloc_inode),
2399 					 group_bh,
2400 					 undo_fn ?
2401 					 OCFS2_JOURNAL_ACCESS_UNDO :
2402 					 OCFS2_JOURNAL_ACCESS_WRITE);
2403 	if (status < 0) {
2404 		mlog_errno(status);
2405 		goto bail;
2406 	}
2407 
2408 	if (undo_fn) {
2409 		jbd_lock_bh_state(group_bh);
2410 		undo_bg = (struct ocfs2_group_desc *)
2411 					bh2jh(group_bh)->b_committed_data;
2412 		BUG_ON(!undo_bg);
2413 	}
2414 
2415 	tmp = num_bits;
2416 	while(tmp--) {
2417 		ocfs2_clear_bit((bit_off + tmp),
2418 				(unsigned long *) bg->bg_bitmap);
2419 		if (undo_fn)
2420 			undo_fn(bit_off + tmp,
2421 				(unsigned long *) undo_bg->bg_bitmap);
2422 	}
2423 	le16_add_cpu(&bg->bg_free_bits_count, num_bits);
2424 	if (le16_to_cpu(bg->bg_free_bits_count) > le16_to_cpu(bg->bg_bits)) {
2425 		if (undo_fn)
2426 			jbd_unlock_bh_state(group_bh);
2427 		return ocfs2_error(alloc_inode->i_sb, "Group descriptor # %llu has bit count %u but claims %u are freed. num_bits %d\n",
2428 				   (unsigned long long)le64_to_cpu(bg->bg_blkno),
2429 				   le16_to_cpu(bg->bg_bits),
2430 				   le16_to_cpu(bg->bg_free_bits_count),
2431 				   num_bits);
2432 	}
2433 
2434 	if (undo_fn)
2435 		jbd_unlock_bh_state(group_bh);
2436 
2437 	ocfs2_journal_dirty(handle, group_bh);
2438 bail:
2439 	return status;
2440 }
2441 
2442 /*
2443  * expects the suballoc inode to already be locked.
2444  */
_ocfs2_free_suballoc_bits(handle_t * handle,struct inode * alloc_inode,struct buffer_head * alloc_bh,unsigned int start_bit,u64 bg_blkno,unsigned int count,void (* undo_fn)(unsigned int bit,unsigned long * bitmap))2445 static int _ocfs2_free_suballoc_bits(handle_t *handle,
2446 				     struct inode *alloc_inode,
2447 				     struct buffer_head *alloc_bh,
2448 				     unsigned int start_bit,
2449 				     u64 bg_blkno,
2450 				     unsigned int count,
2451 				     void (*undo_fn)(unsigned int bit,
2452 						     unsigned long *bitmap))
2453 {
2454 	int status = 0;
2455 	u32 tmp_used;
2456 	struct ocfs2_dinode *fe = (struct ocfs2_dinode *) alloc_bh->b_data;
2457 	struct ocfs2_chain_list *cl = &fe->id2.i_chain;
2458 	struct buffer_head *group_bh = NULL;
2459 	struct ocfs2_group_desc *group;
2460 
2461 	/* The alloc_bh comes from ocfs2_free_dinode() or
2462 	 * ocfs2_free_clusters().  The callers have all locked the
2463 	 * allocator and gotten alloc_bh from the lock call.  This
2464 	 * validates the dinode buffer.  Any corruption that has happened
2465 	 * is a code bug. */
2466 	BUG_ON(!OCFS2_IS_VALID_DINODE(fe));
2467 	BUG_ON((count + start_bit) > ocfs2_bits_per_group(cl));
2468 
2469 	trace_ocfs2_free_suballoc_bits(
2470 		(unsigned long long)OCFS2_I(alloc_inode)->ip_blkno,
2471 		(unsigned long long)bg_blkno,
2472 		start_bit, count);
2473 
2474 	status = ocfs2_read_group_descriptor(alloc_inode, fe, bg_blkno,
2475 					     &group_bh);
2476 	if (status < 0) {
2477 		mlog_errno(status);
2478 		goto bail;
2479 	}
2480 	group = (struct ocfs2_group_desc *) group_bh->b_data;
2481 
2482 	BUG_ON((count + start_bit) > le16_to_cpu(group->bg_bits));
2483 
2484 	status = ocfs2_block_group_clear_bits(handle, alloc_inode,
2485 					      group, group_bh,
2486 					      start_bit, count, undo_fn);
2487 	if (status < 0) {
2488 		mlog_errno(status);
2489 		goto bail;
2490 	}
2491 
2492 	status = ocfs2_journal_access_di(handle, INODE_CACHE(alloc_inode),
2493 					 alloc_bh, OCFS2_JOURNAL_ACCESS_WRITE);
2494 	if (status < 0) {
2495 		mlog_errno(status);
2496 		ocfs2_block_group_set_bits(handle, alloc_inode, group, group_bh,
2497 				start_bit, count);
2498 		goto bail;
2499 	}
2500 
2501 	le32_add_cpu(&cl->cl_recs[le16_to_cpu(group->bg_chain)].c_free,
2502 		     count);
2503 	tmp_used = le32_to_cpu(fe->id1.bitmap1.i_used);
2504 	fe->id1.bitmap1.i_used = cpu_to_le32(tmp_used - count);
2505 	ocfs2_journal_dirty(handle, alloc_bh);
2506 
2507 bail:
2508 	brelse(group_bh);
2509 
2510 	if (status)
2511 		mlog_errno(status);
2512 	return status;
2513 }
2514 
ocfs2_free_suballoc_bits(handle_t * handle,struct inode * alloc_inode,struct buffer_head * alloc_bh,unsigned int start_bit,u64 bg_blkno,unsigned int count)2515 int ocfs2_free_suballoc_bits(handle_t *handle,
2516 			     struct inode *alloc_inode,
2517 			     struct buffer_head *alloc_bh,
2518 			     unsigned int start_bit,
2519 			     u64 bg_blkno,
2520 			     unsigned int count)
2521 {
2522 	return _ocfs2_free_suballoc_bits(handle, alloc_inode, alloc_bh,
2523 					 start_bit, bg_blkno, count, NULL);
2524 }
2525 
ocfs2_free_dinode(handle_t * handle,struct inode * inode_alloc_inode,struct buffer_head * inode_alloc_bh,struct ocfs2_dinode * di)2526 int ocfs2_free_dinode(handle_t *handle,
2527 		      struct inode *inode_alloc_inode,
2528 		      struct buffer_head *inode_alloc_bh,
2529 		      struct ocfs2_dinode *di)
2530 {
2531 	u64 blk = le64_to_cpu(di->i_blkno);
2532 	u16 bit = le16_to_cpu(di->i_suballoc_bit);
2533 	u64 bg_blkno = ocfs2_which_suballoc_group(blk, bit);
2534 
2535 	if (di->i_suballoc_loc)
2536 		bg_blkno = le64_to_cpu(di->i_suballoc_loc);
2537 	return ocfs2_free_suballoc_bits(handle, inode_alloc_inode,
2538 					inode_alloc_bh, bit, bg_blkno, 1);
2539 }
2540 
_ocfs2_free_clusters(handle_t * handle,struct inode * bitmap_inode,struct buffer_head * bitmap_bh,u64 start_blk,unsigned int num_clusters,void (* undo_fn)(unsigned int bit,unsigned long * bitmap))2541 static int _ocfs2_free_clusters(handle_t *handle,
2542 				struct inode *bitmap_inode,
2543 				struct buffer_head *bitmap_bh,
2544 				u64 start_blk,
2545 				unsigned int num_clusters,
2546 				void (*undo_fn)(unsigned int bit,
2547 						unsigned long *bitmap))
2548 {
2549 	int status;
2550 	u16 bg_start_bit;
2551 	u64 bg_blkno;
2552 
2553 	/* You can't ever have a contiguous set of clusters
2554 	 * bigger than a block group bitmap so we never have to worry
2555 	 * about looping on them.
2556 	 * This is expensive. We can safely remove once this stuff has
2557 	 * gotten tested really well. */
2558 	BUG_ON(start_blk != ocfs2_clusters_to_blocks(bitmap_inode->i_sb,
2559 				ocfs2_blocks_to_clusters(bitmap_inode->i_sb,
2560 							 start_blk)));
2561 
2562 
2563 	ocfs2_block_to_cluster_group(bitmap_inode, start_blk, &bg_blkno,
2564 				     &bg_start_bit);
2565 
2566 	trace_ocfs2_free_clusters((unsigned long long)bg_blkno,
2567 			(unsigned long long)start_blk,
2568 			bg_start_bit, num_clusters);
2569 
2570 	status = _ocfs2_free_suballoc_bits(handle, bitmap_inode, bitmap_bh,
2571 					   bg_start_bit, bg_blkno,
2572 					   num_clusters, undo_fn);
2573 	if (status < 0) {
2574 		mlog_errno(status);
2575 		goto out;
2576 	}
2577 
2578 	ocfs2_local_alloc_seen_free_bits(OCFS2_SB(bitmap_inode->i_sb),
2579 					 num_clusters);
2580 
2581 out:
2582 	if (status)
2583 		mlog_errno(status);
2584 	return status;
2585 }
2586 
ocfs2_free_clusters(handle_t * handle,struct inode * bitmap_inode,struct buffer_head * bitmap_bh,u64 start_blk,unsigned int num_clusters)2587 int ocfs2_free_clusters(handle_t *handle,
2588 			struct inode *bitmap_inode,
2589 			struct buffer_head *bitmap_bh,
2590 			u64 start_blk,
2591 			unsigned int num_clusters)
2592 {
2593 	return _ocfs2_free_clusters(handle, bitmap_inode, bitmap_bh,
2594 				    start_blk, num_clusters,
2595 				    _ocfs2_set_bit);
2596 }
2597 
2598 /*
2599  * Give never-used clusters back to the global bitmap.  We don't need
2600  * to protect these bits in the undo buffer.
2601  */
ocfs2_release_clusters(handle_t * handle,struct inode * bitmap_inode,struct buffer_head * bitmap_bh,u64 start_blk,unsigned int num_clusters)2602 int ocfs2_release_clusters(handle_t *handle,
2603 			   struct inode *bitmap_inode,
2604 			   struct buffer_head *bitmap_bh,
2605 			   u64 start_blk,
2606 			   unsigned int num_clusters)
2607 {
2608 	return _ocfs2_free_clusters(handle, bitmap_inode, bitmap_bh,
2609 				    start_blk, num_clusters,
2610 				    _ocfs2_clear_bit);
2611 }
2612 
2613 /*
2614  * For a given allocation, determine which allocators will need to be
2615  * accessed, and lock them, reserving the appropriate number of bits.
2616  *
2617  * Sparse file systems call this from ocfs2_write_begin_nolock()
2618  * and ocfs2_allocate_unwritten_extents().
2619  *
2620  * File systems which don't support holes call this from
2621  * ocfs2_extend_allocation().
2622  */
ocfs2_lock_allocators(struct inode * inode,struct ocfs2_extent_tree * et,u32 clusters_to_add,u32 extents_to_split,struct ocfs2_alloc_context ** data_ac,struct ocfs2_alloc_context ** meta_ac)2623 int ocfs2_lock_allocators(struct inode *inode,
2624 			  struct ocfs2_extent_tree *et,
2625 			  u32 clusters_to_add, u32 extents_to_split,
2626 			  struct ocfs2_alloc_context **data_ac,
2627 			  struct ocfs2_alloc_context **meta_ac)
2628 {
2629 	int ret = 0, num_free_extents;
2630 	unsigned int max_recs_needed = clusters_to_add + 2 * extents_to_split;
2631 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
2632 
2633 	*meta_ac = NULL;
2634 	if (data_ac)
2635 		*data_ac = NULL;
2636 
2637 	BUG_ON(clusters_to_add != 0 && data_ac == NULL);
2638 
2639 	num_free_extents = ocfs2_num_free_extents(et);
2640 	if (num_free_extents < 0) {
2641 		ret = num_free_extents;
2642 		mlog_errno(ret);
2643 		goto out;
2644 	}
2645 
2646 	/*
2647 	 * Sparse allocation file systems need to be more conservative
2648 	 * with reserving room for expansion - the actual allocation
2649 	 * happens while we've got a journal handle open so re-taking
2650 	 * a cluster lock (because we ran out of room for another
2651 	 * extent) will violate ordering rules.
2652 	 *
2653 	 * Most of the time we'll only be seeing this 1 cluster at a time
2654 	 * anyway.
2655 	 *
2656 	 * Always lock for any unwritten extents - we might want to
2657 	 * add blocks during a split.
2658 	 */
2659 	if (!num_free_extents ||
2660 	    (ocfs2_sparse_alloc(osb) && num_free_extents < max_recs_needed)) {
2661 		ret = ocfs2_reserve_new_metadata(osb, et->et_root_el, meta_ac);
2662 		if (ret < 0) {
2663 			if (ret != -ENOSPC)
2664 				mlog_errno(ret);
2665 			goto out;
2666 		}
2667 	}
2668 
2669 	if (clusters_to_add == 0)
2670 		goto out;
2671 
2672 	ret = ocfs2_reserve_clusters(osb, clusters_to_add, data_ac);
2673 	if (ret < 0) {
2674 		if (ret != -ENOSPC)
2675 			mlog_errno(ret);
2676 		goto out;
2677 	}
2678 
2679 out:
2680 	if (ret) {
2681 		if (*meta_ac) {
2682 			ocfs2_free_alloc_context(*meta_ac);
2683 			*meta_ac = NULL;
2684 		}
2685 
2686 		/*
2687 		 * We cannot have an error and a non null *data_ac.
2688 		 */
2689 	}
2690 
2691 	return ret;
2692 }
2693 
2694 /*
2695  * Read the inode specified by blkno to get suballoc_slot and
2696  * suballoc_bit.
2697  */
ocfs2_get_suballoc_slot_bit(struct ocfs2_super * osb,u64 blkno,u16 * suballoc_slot,u64 * group_blkno,u16 * suballoc_bit)2698 static int ocfs2_get_suballoc_slot_bit(struct ocfs2_super *osb, u64 blkno,
2699 				       u16 *suballoc_slot, u64 *group_blkno,
2700 				       u16 *suballoc_bit)
2701 {
2702 	int status;
2703 	struct buffer_head *inode_bh = NULL;
2704 	struct ocfs2_dinode *inode_fe;
2705 
2706 	trace_ocfs2_get_suballoc_slot_bit((unsigned long long)blkno);
2707 
2708 	/* dirty read disk */
2709 	status = ocfs2_read_blocks_sync(osb, blkno, 1, &inode_bh);
2710 	if (status < 0) {
2711 		mlog(ML_ERROR, "read block %llu failed %d\n",
2712 		     (unsigned long long)blkno, status);
2713 		goto bail;
2714 	}
2715 
2716 	inode_fe = (struct ocfs2_dinode *) inode_bh->b_data;
2717 	if (!OCFS2_IS_VALID_DINODE(inode_fe)) {
2718 		mlog(ML_ERROR, "invalid inode %llu requested\n",
2719 		     (unsigned long long)blkno);
2720 		status = -EINVAL;
2721 		goto bail;
2722 	}
2723 
2724 	if (le16_to_cpu(inode_fe->i_suballoc_slot) != (u16)OCFS2_INVALID_SLOT &&
2725 	    (u32)le16_to_cpu(inode_fe->i_suballoc_slot) > osb->max_slots - 1) {
2726 		mlog(ML_ERROR, "inode %llu has invalid suballoc slot %u\n",
2727 		     (unsigned long long)blkno,
2728 		     (u32)le16_to_cpu(inode_fe->i_suballoc_slot));
2729 		status = -EINVAL;
2730 		goto bail;
2731 	}
2732 
2733 	if (suballoc_slot)
2734 		*suballoc_slot = le16_to_cpu(inode_fe->i_suballoc_slot);
2735 	if (suballoc_bit)
2736 		*suballoc_bit = le16_to_cpu(inode_fe->i_suballoc_bit);
2737 	if (group_blkno)
2738 		*group_blkno = le64_to_cpu(inode_fe->i_suballoc_loc);
2739 
2740 bail:
2741 	brelse(inode_bh);
2742 
2743 	if (status)
2744 		mlog_errno(status);
2745 	return status;
2746 }
2747 
2748 /*
2749  * test whether bit is SET in allocator bitmap or not.  on success, 0
2750  * is returned and *res is 1 for SET; 0 otherwise.  when fails, errno
2751  * is returned and *res is meaningless.  Call this after you have
2752  * cluster locked against suballoc, or you may get a result based on
2753  * non-up2date contents
2754  */
ocfs2_test_suballoc_bit(struct ocfs2_super * osb,struct inode * suballoc,struct buffer_head * alloc_bh,u64 group_blkno,u64 blkno,u16 bit,int * res)2755 static int ocfs2_test_suballoc_bit(struct ocfs2_super *osb,
2756 				   struct inode *suballoc,
2757 				   struct buffer_head *alloc_bh,
2758 				   u64 group_blkno, u64 blkno,
2759 				   u16 bit, int *res)
2760 {
2761 	struct ocfs2_dinode *alloc_di;
2762 	struct ocfs2_group_desc *group;
2763 	struct buffer_head *group_bh = NULL;
2764 	u64 bg_blkno;
2765 	int status;
2766 
2767 	trace_ocfs2_test_suballoc_bit((unsigned long long)blkno,
2768 				      (unsigned int)bit);
2769 
2770 	alloc_di = (struct ocfs2_dinode *)alloc_bh->b_data;
2771 	if ((bit + 1) > ocfs2_bits_per_group(&alloc_di->id2.i_chain)) {
2772 		mlog(ML_ERROR, "suballoc bit %u out of range of %u\n",
2773 		     (unsigned int)bit,
2774 		     ocfs2_bits_per_group(&alloc_di->id2.i_chain));
2775 		status = -EINVAL;
2776 		goto bail;
2777 	}
2778 
2779 	bg_blkno = group_blkno ? group_blkno :
2780 		   ocfs2_which_suballoc_group(blkno, bit);
2781 	status = ocfs2_read_group_descriptor(suballoc, alloc_di, bg_blkno,
2782 					     &group_bh);
2783 	if (status < 0) {
2784 		mlog(ML_ERROR, "read group %llu failed %d\n",
2785 		     (unsigned long long)bg_blkno, status);
2786 		goto bail;
2787 	}
2788 
2789 	group = (struct ocfs2_group_desc *) group_bh->b_data;
2790 	*res = ocfs2_test_bit(bit, (unsigned long *)group->bg_bitmap);
2791 
2792 bail:
2793 	brelse(group_bh);
2794 
2795 	if (status)
2796 		mlog_errno(status);
2797 	return status;
2798 }
2799 
2800 /*
2801  * Test if the bit representing this inode (blkno) is set in the
2802  * suballocator.
2803  *
2804  * On success, 0 is returned and *res is 1 for SET; 0 otherwise.
2805  *
2806  * In the event of failure, a negative value is returned and *res is
2807  * meaningless.
2808  *
2809  * Callers must make sure to hold nfs_sync_lock to prevent
2810  * ocfs2_delete_inode() on another node from accessing the same
2811  * suballocator concurrently.
2812  */
ocfs2_test_inode_bit(struct ocfs2_super * osb,u64 blkno,int * res)2813 int ocfs2_test_inode_bit(struct ocfs2_super *osb, u64 blkno, int *res)
2814 {
2815 	int status;
2816 	u64 group_blkno = 0;
2817 	u16 suballoc_bit = 0, suballoc_slot = 0;
2818 	struct inode *inode_alloc_inode;
2819 	struct buffer_head *alloc_bh = NULL;
2820 
2821 	trace_ocfs2_test_inode_bit((unsigned long long)blkno);
2822 
2823 	status = ocfs2_get_suballoc_slot_bit(osb, blkno, &suballoc_slot,
2824 					     &group_blkno, &suballoc_bit);
2825 	if (status < 0) {
2826 		mlog(ML_ERROR, "get alloc slot and bit failed %d\n", status);
2827 		goto bail;
2828 	}
2829 
2830 	inode_alloc_inode =
2831 		ocfs2_get_system_file_inode(osb, INODE_ALLOC_SYSTEM_INODE,
2832 					    suballoc_slot);
2833 	if (!inode_alloc_inode) {
2834 		/* the error code could be inaccurate, but we are not able to
2835 		 * get the correct one. */
2836 		status = -EINVAL;
2837 		mlog(ML_ERROR, "unable to get alloc inode in slot %u\n",
2838 		     (u32)suballoc_slot);
2839 		goto bail;
2840 	}
2841 
2842 	inode_lock(inode_alloc_inode);
2843 	status = ocfs2_inode_lock(inode_alloc_inode, &alloc_bh, 0);
2844 	if (status < 0) {
2845 		inode_unlock(inode_alloc_inode);
2846 		iput(inode_alloc_inode);
2847 		mlog(ML_ERROR, "lock on alloc inode on slot %u failed %d\n",
2848 		     (u32)suballoc_slot, status);
2849 		goto bail;
2850 	}
2851 
2852 	status = ocfs2_test_suballoc_bit(osb, inode_alloc_inode, alloc_bh,
2853 					 group_blkno, blkno, suballoc_bit, res);
2854 	if (status < 0)
2855 		mlog(ML_ERROR, "test suballoc bit failed %d\n", status);
2856 
2857 	ocfs2_inode_unlock(inode_alloc_inode, 0);
2858 	inode_unlock(inode_alloc_inode);
2859 
2860 	iput(inode_alloc_inode);
2861 	brelse(alloc_bh);
2862 bail:
2863 	if (status)
2864 		mlog_errno(status);
2865 	return status;
2866 }
2867