1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2017-2018 HUAWEI, Inc.
4 * https://www.huawei.com/
5 * Copyright (C) 2021, Alibaba Cloud
6 */
7 #include "xattr.h"
8
9 #include <trace/events/erofs.h>
10
11 /*
12 * if inode is successfully read, return its inode page (or sometimes
13 * the inode payload page if it's an extended inode) in order to fill
14 * inline data if possible.
15 */
erofs_read_inode(struct inode * inode,unsigned int * ofs)16 static struct page *erofs_read_inode(struct inode *inode,
17 unsigned int *ofs)
18 {
19 struct super_block *sb = inode->i_sb;
20 struct erofs_sb_info *sbi = EROFS_SB(sb);
21 struct erofs_inode *vi = EROFS_I(inode);
22 const erofs_off_t inode_loc = iloc(sbi, vi->nid);
23
24 erofs_blk_t blkaddr, nblks = 0;
25 struct page *page;
26 struct erofs_inode_compact *dic;
27 struct erofs_inode_extended *die, *copied = NULL;
28 unsigned int ifmt;
29 int err;
30
31 blkaddr = erofs_blknr(inode_loc);
32 *ofs = erofs_blkoff(inode_loc);
33
34 erofs_dbg("%s, reading inode nid %llu at %u of blkaddr %u",
35 __func__, vi->nid, *ofs, blkaddr);
36
37 page = erofs_get_meta_page(sb, blkaddr);
38 if (IS_ERR(page)) {
39 erofs_err(sb, "failed to get inode (nid: %llu) page, err %ld",
40 vi->nid, PTR_ERR(page));
41 return page;
42 }
43
44 dic = page_address(page) + *ofs;
45 ifmt = le16_to_cpu(dic->i_format);
46
47 if (ifmt & ~EROFS_I_ALL) {
48 erofs_err(inode->i_sb, "unsupported i_format %u of nid %llu",
49 ifmt, vi->nid);
50 err = -EOPNOTSUPP;
51 goto err_out;
52 }
53
54 vi->datalayout = erofs_inode_datalayout(ifmt);
55 if (vi->datalayout >= EROFS_INODE_DATALAYOUT_MAX) {
56 erofs_err(inode->i_sb, "unsupported datalayout %u of nid %llu",
57 vi->datalayout, vi->nid);
58 err = -EOPNOTSUPP;
59 goto err_out;
60 }
61
62 switch (erofs_inode_version(ifmt)) {
63 case EROFS_INODE_LAYOUT_EXTENDED:
64 vi->inode_isize = sizeof(struct erofs_inode_extended);
65 /* check if the inode acrosses page boundary */
66 if (*ofs + vi->inode_isize <= PAGE_SIZE) {
67 *ofs += vi->inode_isize;
68 die = (struct erofs_inode_extended *)dic;
69 } else {
70 const unsigned int gotten = PAGE_SIZE - *ofs;
71
72 copied = kmalloc(vi->inode_isize, GFP_NOFS);
73 if (!copied) {
74 err = -ENOMEM;
75 goto err_out;
76 }
77 memcpy(copied, dic, gotten);
78 unlock_page(page);
79 put_page(page);
80
81 page = erofs_get_meta_page(sb, blkaddr + 1);
82 if (IS_ERR(page)) {
83 erofs_err(sb, "failed to get inode payload page (nid: %llu), err %ld",
84 vi->nid, PTR_ERR(page));
85 kfree(copied);
86 return page;
87 }
88 *ofs = vi->inode_isize - gotten;
89 memcpy((u8 *)copied + gotten, page_address(page), *ofs);
90 die = copied;
91 }
92 vi->xattr_isize = erofs_xattr_ibody_size(die->i_xattr_icount);
93
94 inode->i_mode = le16_to_cpu(die->i_mode);
95 switch (inode->i_mode & S_IFMT) {
96 case S_IFREG:
97 case S_IFDIR:
98 case S_IFLNK:
99 vi->raw_blkaddr = le32_to_cpu(die->i_u.raw_blkaddr);
100 break;
101 case S_IFCHR:
102 case S_IFBLK:
103 inode->i_rdev =
104 new_decode_dev(le32_to_cpu(die->i_u.rdev));
105 break;
106 case S_IFIFO:
107 case S_IFSOCK:
108 inode->i_rdev = 0;
109 break;
110 default:
111 goto bogusimode;
112 }
113 i_uid_write(inode, le32_to_cpu(die->i_uid));
114 i_gid_write(inode, le32_to_cpu(die->i_gid));
115 set_nlink(inode, le32_to_cpu(die->i_nlink));
116
117 /* extended inode has its own timestamp */
118 inode->i_ctime.tv_sec = le64_to_cpu(die->i_ctime);
119 inode->i_ctime.tv_nsec = le32_to_cpu(die->i_ctime_nsec);
120
121 inode->i_size = le64_to_cpu(die->i_size);
122
123 /* total blocks for compressed files */
124 if (erofs_inode_is_data_compressed(vi->datalayout))
125 nblks = le32_to_cpu(die->i_u.compressed_blocks);
126 else if (vi->datalayout == EROFS_INODE_CHUNK_BASED)
127 /* fill chunked inode summary info */
128 vi->chunkformat = le16_to_cpu(die->i_u.c.format);
129 kfree(copied);
130 copied = NULL;
131 break;
132 case EROFS_INODE_LAYOUT_COMPACT:
133 vi->inode_isize = sizeof(struct erofs_inode_compact);
134 *ofs += vi->inode_isize;
135 vi->xattr_isize = erofs_xattr_ibody_size(dic->i_xattr_icount);
136
137 inode->i_mode = le16_to_cpu(dic->i_mode);
138 switch (inode->i_mode & S_IFMT) {
139 case S_IFREG:
140 case S_IFDIR:
141 case S_IFLNK:
142 vi->raw_blkaddr = le32_to_cpu(dic->i_u.raw_blkaddr);
143 break;
144 case S_IFCHR:
145 case S_IFBLK:
146 inode->i_rdev =
147 new_decode_dev(le32_to_cpu(dic->i_u.rdev));
148 break;
149 case S_IFIFO:
150 case S_IFSOCK:
151 inode->i_rdev = 0;
152 break;
153 default:
154 goto bogusimode;
155 }
156 i_uid_write(inode, le16_to_cpu(dic->i_uid));
157 i_gid_write(inode, le16_to_cpu(dic->i_gid));
158 set_nlink(inode, le16_to_cpu(dic->i_nlink));
159
160 /* use build time for compact inodes */
161 inode->i_ctime.tv_sec = sbi->build_time;
162 inode->i_ctime.tv_nsec = sbi->build_time_nsec;
163
164 inode->i_size = le32_to_cpu(dic->i_size);
165 if (erofs_inode_is_data_compressed(vi->datalayout))
166 nblks = le32_to_cpu(dic->i_u.compressed_blocks);
167 else if (vi->datalayout == EROFS_INODE_CHUNK_BASED)
168 vi->chunkformat = le16_to_cpu(dic->i_u.c.format);
169 break;
170 default:
171 erofs_err(inode->i_sb,
172 "unsupported on-disk inode version %u of nid %llu",
173 erofs_inode_version(ifmt), vi->nid);
174 err = -EOPNOTSUPP;
175 goto err_out;
176 }
177
178 if (vi->datalayout == EROFS_INODE_CHUNK_BASED) {
179 if (vi->chunkformat & ~EROFS_CHUNK_FORMAT_ALL) {
180 erofs_err(inode->i_sb,
181 "unsupported chunk format %x of nid %llu",
182 vi->chunkformat, vi->nid);
183 err = -EOPNOTSUPP;
184 goto err_out;
185 }
186 vi->chunkbits = LOG_BLOCK_SIZE +
187 (vi->chunkformat & EROFS_CHUNK_FORMAT_BLKBITS_MASK);
188 }
189 inode->i_mtime.tv_sec = inode->i_ctime.tv_sec;
190 inode->i_atime.tv_sec = inode->i_ctime.tv_sec;
191 inode->i_mtime.tv_nsec = inode->i_ctime.tv_nsec;
192 inode->i_atime.tv_nsec = inode->i_ctime.tv_nsec;
193
194 inode->i_flags &= ~S_DAX;
195 if (test_opt(&sbi->opt, DAX_ALWAYS) && S_ISREG(inode->i_mode) &&
196 (vi->datalayout == EROFS_INODE_FLAT_PLAIN ||
197 vi->datalayout == EROFS_INODE_CHUNK_BASED))
198 inode->i_flags |= S_DAX;
199 if (!nblks)
200 /* measure inode.i_blocks as generic filesystems */
201 inode->i_blocks = roundup(inode->i_size, EROFS_BLKSIZ) >> 9;
202 else
203 inode->i_blocks = nblks << LOG_SECTORS_PER_BLOCK;
204 return page;
205
206 bogusimode:
207 erofs_err(inode->i_sb, "bogus i_mode (%o) @ nid %llu",
208 inode->i_mode, vi->nid);
209 err = -EFSCORRUPTED;
210 err_out:
211 DBG_BUGON(1);
212 kfree(copied);
213 unlock_page(page);
214 put_page(page);
215 return ERR_PTR(err);
216 }
217
erofs_fill_symlink(struct inode * inode,void * data,unsigned int m_pofs)218 static int erofs_fill_symlink(struct inode *inode, void *data,
219 unsigned int m_pofs)
220 {
221 struct erofs_inode *vi = EROFS_I(inode);
222 char *lnk;
223
224 /* if it cannot be handled with fast symlink scheme */
225 if (vi->datalayout != EROFS_INODE_FLAT_INLINE ||
226 inode->i_size >= PAGE_SIZE || inode->i_size < 0) {
227 inode->i_op = &erofs_symlink_iops;
228 return 0;
229 }
230
231 lnk = kmalloc(inode->i_size + 1, GFP_KERNEL);
232 if (!lnk)
233 return -ENOMEM;
234
235 m_pofs += vi->xattr_isize;
236 /* inline symlink data shouldn't cross page boundary as well */
237 if (m_pofs + inode->i_size > PAGE_SIZE) {
238 kfree(lnk);
239 erofs_err(inode->i_sb,
240 "inline data cross block boundary @ nid %llu",
241 vi->nid);
242 DBG_BUGON(1);
243 return -EFSCORRUPTED;
244 }
245
246 memcpy(lnk, data + m_pofs, inode->i_size);
247 lnk[inode->i_size] = '\0';
248
249 inode->i_link = lnk;
250 inode->i_op = &erofs_fast_symlink_iops;
251 return 0;
252 }
253
erofs_fill_inode(struct inode * inode,int isdir)254 static int erofs_fill_inode(struct inode *inode, int isdir)
255 {
256 struct erofs_inode *vi = EROFS_I(inode);
257 struct page *page;
258 unsigned int ofs;
259 int err = 0;
260
261 trace_erofs_fill_inode(inode, isdir);
262
263 /* read inode base data from disk */
264 page = erofs_read_inode(inode, &ofs);
265 if (IS_ERR(page))
266 return PTR_ERR(page);
267
268 /* setup the new inode */
269 switch (inode->i_mode & S_IFMT) {
270 case S_IFREG:
271 inode->i_op = &erofs_generic_iops;
272 if (erofs_inode_is_data_compressed(vi->datalayout))
273 inode->i_fop = &generic_ro_fops;
274 else
275 inode->i_fop = &erofs_file_fops;
276 break;
277 case S_IFDIR:
278 inode->i_op = &erofs_dir_iops;
279 inode->i_fop = &erofs_dir_fops;
280 break;
281 case S_IFLNK:
282 err = erofs_fill_symlink(inode, page_address(page), ofs);
283 if (err)
284 goto out_unlock;
285 inode_nohighmem(inode);
286 break;
287 case S_IFCHR:
288 case S_IFBLK:
289 case S_IFIFO:
290 case S_IFSOCK:
291 inode->i_op = &erofs_generic_iops;
292 init_special_inode(inode, inode->i_mode, inode->i_rdev);
293 goto out_unlock;
294 default:
295 err = -EFSCORRUPTED;
296 goto out_unlock;
297 }
298
299 if (erofs_inode_is_data_compressed(vi->datalayout)) {
300 err = z_erofs_fill_inode(inode);
301 goto out_unlock;
302 }
303 inode->i_mapping->a_ops = &erofs_raw_access_aops;
304
305 out_unlock:
306 unlock_page(page);
307 put_page(page);
308 return err;
309 }
310
311 /*
312 * erofs nid is 64bits, but i_ino is 'unsigned long', therefore
313 * we should do more for 32-bit platform to find the right inode.
314 */
erofs_ilookup_test_actor(struct inode * inode,void * opaque)315 static int erofs_ilookup_test_actor(struct inode *inode, void *opaque)
316 {
317 const erofs_nid_t nid = *(erofs_nid_t *)opaque;
318
319 return EROFS_I(inode)->nid == nid;
320 }
321
erofs_iget_set_actor(struct inode * inode,void * opaque)322 static int erofs_iget_set_actor(struct inode *inode, void *opaque)
323 {
324 const erofs_nid_t nid = *(erofs_nid_t *)opaque;
325
326 inode->i_ino = erofs_inode_hash(nid);
327 return 0;
328 }
329
erofs_iget_locked(struct super_block * sb,erofs_nid_t nid)330 static inline struct inode *erofs_iget_locked(struct super_block *sb,
331 erofs_nid_t nid)
332 {
333 const unsigned long hashval = erofs_inode_hash(nid);
334
335 return iget5_locked(sb, hashval, erofs_ilookup_test_actor,
336 erofs_iget_set_actor, &nid);
337 }
338
erofs_iget(struct super_block * sb,erofs_nid_t nid,bool isdir)339 struct inode *erofs_iget(struct super_block *sb,
340 erofs_nid_t nid,
341 bool isdir)
342 {
343 struct inode *inode = erofs_iget_locked(sb, nid);
344
345 if (!inode)
346 return ERR_PTR(-ENOMEM);
347
348 if (inode->i_state & I_NEW) {
349 int err;
350 struct erofs_inode *vi = EROFS_I(inode);
351
352 vi->nid = nid;
353
354 err = erofs_fill_inode(inode, isdir);
355 if (!err)
356 unlock_new_inode(inode);
357 else {
358 iget_failed(inode);
359 inode = ERR_PTR(err);
360 }
361 }
362 return inode;
363 }
364
erofs_getattr(struct user_namespace * mnt_userns,const struct path * path,struct kstat * stat,u32 request_mask,unsigned int query_flags)365 int erofs_getattr(struct user_namespace *mnt_userns, const struct path *path,
366 struct kstat *stat, u32 request_mask,
367 unsigned int query_flags)
368 {
369 struct inode *const inode = d_inode(path->dentry);
370
371 if (erofs_inode_is_data_compressed(EROFS_I(inode)->datalayout))
372 stat->attributes |= STATX_ATTR_COMPRESSED;
373
374 stat->attributes |= STATX_ATTR_IMMUTABLE;
375 stat->attributes_mask |= (STATX_ATTR_COMPRESSED |
376 STATX_ATTR_IMMUTABLE);
377
378 generic_fillattr(&init_user_ns, inode, stat);
379 return 0;
380 }
381
382 const struct inode_operations erofs_generic_iops = {
383 .getattr = erofs_getattr,
384 .listxattr = erofs_listxattr,
385 .get_acl = erofs_get_acl,
386 .fiemap = erofs_fiemap,
387 };
388
389 const struct inode_operations erofs_symlink_iops = {
390 .get_link = page_get_link,
391 .getattr = erofs_getattr,
392 .listxattr = erofs_listxattr,
393 .get_acl = erofs_get_acl,
394 };
395
396 const struct inode_operations erofs_fast_symlink_iops = {
397 .get_link = simple_get_link,
398 .getattr = erofs_getattr,
399 .listxattr = erofs_listxattr,
400 .get_acl = erofs_get_acl,
401 };
402