Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
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
11static void *erofs_read_inode(struct erofs_buf *buf,
12 struct inode *inode, unsigned int *ofs)
13{
14 struct super_block *sb = inode->i_sb;
15 struct erofs_sb_info *sbi = EROFS_SB(sb);
16 struct erofs_inode *vi = EROFS_I(inode);
17 const erofs_off_t inode_loc = erofs_iloc(inode);
18
19 erofs_blk_t blkaddr, nblks = 0;
20 void *kaddr;
21 struct erofs_inode_compact *dic;
22 struct erofs_inode_extended *die, *copied = NULL;
23 unsigned int ifmt;
24 int err;
25
26 blkaddr = erofs_blknr(sb, inode_loc);
27 *ofs = erofs_blkoff(sb, inode_loc);
28
29 kaddr = erofs_read_metabuf(buf, sb, blkaddr, EROFS_KMAP);
30 if (IS_ERR(kaddr)) {
31 erofs_err(sb, "failed to get inode (nid: %llu) page, err %ld",
32 vi->nid, PTR_ERR(kaddr));
33 return kaddr;
34 }
35
36 dic = kaddr + *ofs;
37 ifmt = le16_to_cpu(dic->i_format);
38
39 if (ifmt & ~EROFS_I_ALL) {
40 erofs_err(inode->i_sb, "unsupported i_format %u of nid %llu",
41 ifmt, vi->nid);
42 err = -EOPNOTSUPP;
43 goto err_out;
44 }
45
46 vi->datalayout = erofs_inode_datalayout(ifmt);
47 if (vi->datalayout >= EROFS_INODE_DATALAYOUT_MAX) {
48 erofs_err(inode->i_sb, "unsupported datalayout %u of nid %llu",
49 vi->datalayout, vi->nid);
50 err = -EOPNOTSUPP;
51 goto err_out;
52 }
53
54 switch (erofs_inode_version(ifmt)) {
55 case EROFS_INODE_LAYOUT_EXTENDED:
56 vi->inode_isize = sizeof(struct erofs_inode_extended);
57 /* check if the extended inode acrosses block boundary */
58 if (*ofs + vi->inode_isize <= sb->s_blocksize) {
59 *ofs += vi->inode_isize;
60 die = (struct erofs_inode_extended *)dic;
61 } else {
62 const unsigned int gotten = sb->s_blocksize - *ofs;
63
64 copied = kmalloc(vi->inode_isize, GFP_NOFS);
65 if (!copied) {
66 err = -ENOMEM;
67 goto err_out;
68 }
69 memcpy(copied, dic, gotten);
70 kaddr = erofs_read_metabuf(buf, sb, blkaddr + 1,
71 EROFS_KMAP);
72 if (IS_ERR(kaddr)) {
73 erofs_err(sb, "failed to get inode payload block (nid: %llu), err %ld",
74 vi->nid, PTR_ERR(kaddr));
75 kfree(copied);
76 return kaddr;
77 }
78 *ofs = vi->inode_isize - gotten;
79 memcpy((u8 *)copied + gotten, kaddr, *ofs);
80 die = copied;
81 }
82 vi->xattr_isize = erofs_xattr_ibody_size(die->i_xattr_icount);
83
84 inode->i_mode = le16_to_cpu(die->i_mode);
85 switch (inode->i_mode & S_IFMT) {
86 case S_IFREG:
87 case S_IFDIR:
88 case S_IFLNK:
89 vi->raw_blkaddr = le32_to_cpu(die->i_u.raw_blkaddr);
90 break;
91 case S_IFCHR:
92 case S_IFBLK:
93 inode->i_rdev =
94 new_decode_dev(le32_to_cpu(die->i_u.rdev));
95 break;
96 case S_IFIFO:
97 case S_IFSOCK:
98 inode->i_rdev = 0;
99 break;
100 default:
101 goto bogusimode;
102 }
103 i_uid_write(inode, le32_to_cpu(die->i_uid));
104 i_gid_write(inode, le32_to_cpu(die->i_gid));
105 set_nlink(inode, le32_to_cpu(die->i_nlink));
106
107 /* extended inode has its own timestamp */
108 inode->i_ctime.tv_sec = le64_to_cpu(die->i_mtime);
109 inode->i_ctime.tv_nsec = le32_to_cpu(die->i_mtime_nsec);
110
111 inode->i_size = le64_to_cpu(die->i_size);
112
113 /* total blocks for compressed files */
114 if (erofs_inode_is_data_compressed(vi->datalayout))
115 nblks = le32_to_cpu(die->i_u.compressed_blocks);
116 else if (vi->datalayout == EROFS_INODE_CHUNK_BASED)
117 /* fill chunked inode summary info */
118 vi->chunkformat = le16_to_cpu(die->i_u.c.format);
119 kfree(copied);
120 copied = NULL;
121 break;
122 case EROFS_INODE_LAYOUT_COMPACT:
123 vi->inode_isize = sizeof(struct erofs_inode_compact);
124 *ofs += vi->inode_isize;
125 vi->xattr_isize = erofs_xattr_ibody_size(dic->i_xattr_icount);
126
127 inode->i_mode = le16_to_cpu(dic->i_mode);
128 switch (inode->i_mode & S_IFMT) {
129 case S_IFREG:
130 case S_IFDIR:
131 case S_IFLNK:
132 vi->raw_blkaddr = le32_to_cpu(dic->i_u.raw_blkaddr);
133 break;
134 case S_IFCHR:
135 case S_IFBLK:
136 inode->i_rdev =
137 new_decode_dev(le32_to_cpu(dic->i_u.rdev));
138 break;
139 case S_IFIFO:
140 case S_IFSOCK:
141 inode->i_rdev = 0;
142 break;
143 default:
144 goto bogusimode;
145 }
146 i_uid_write(inode, le16_to_cpu(dic->i_uid));
147 i_gid_write(inode, le16_to_cpu(dic->i_gid));
148 set_nlink(inode, le16_to_cpu(dic->i_nlink));
149
150 /* use build time for compact inodes */
151 inode->i_ctime.tv_sec = sbi->build_time;
152 inode->i_ctime.tv_nsec = sbi->build_time_nsec;
153
154 inode->i_size = le32_to_cpu(dic->i_size);
155 if (erofs_inode_is_data_compressed(vi->datalayout))
156 nblks = le32_to_cpu(dic->i_u.compressed_blocks);
157 else if (vi->datalayout == EROFS_INODE_CHUNK_BASED)
158 vi->chunkformat = le16_to_cpu(dic->i_u.c.format);
159 break;
160 default:
161 erofs_err(inode->i_sb,
162 "unsupported on-disk inode version %u of nid %llu",
163 erofs_inode_version(ifmt), vi->nid);
164 err = -EOPNOTSUPP;
165 goto err_out;
166 }
167
168 if (vi->datalayout == EROFS_INODE_CHUNK_BASED) {
169 if (vi->chunkformat & ~EROFS_CHUNK_FORMAT_ALL) {
170 erofs_err(inode->i_sb,
171 "unsupported chunk format %x of nid %llu",
172 vi->chunkformat, vi->nid);
173 err = -EOPNOTSUPP;
174 goto err_out;
175 }
176 vi->chunkbits = sb->s_blocksize_bits +
177 (vi->chunkformat & EROFS_CHUNK_FORMAT_BLKBITS_MASK);
178 }
179 inode->i_mtime.tv_sec = inode->i_ctime.tv_sec;
180 inode->i_atime.tv_sec = inode->i_ctime.tv_sec;
181 inode->i_mtime.tv_nsec = inode->i_ctime.tv_nsec;
182 inode->i_atime.tv_nsec = inode->i_ctime.tv_nsec;
183
184 inode->i_flags &= ~S_DAX;
185 if (test_opt(&sbi->opt, DAX_ALWAYS) && S_ISREG(inode->i_mode) &&
186 vi->datalayout == EROFS_INODE_FLAT_PLAIN)
187 inode->i_flags |= S_DAX;
188
189 if (!nblks)
190 /* measure inode.i_blocks as generic filesystems */
191 inode->i_blocks = round_up(inode->i_size, sb->s_blocksize) >> 9;
192 else
193 inode->i_blocks = nblks << (sb->s_blocksize_bits - 9);
194 return kaddr;
195
196bogusimode:
197 erofs_err(inode->i_sb, "bogus i_mode (%o) @ nid %llu",
198 inode->i_mode, vi->nid);
199 err = -EFSCORRUPTED;
200err_out:
201 DBG_BUGON(1);
202 kfree(copied);
203 erofs_put_metabuf(buf);
204 return ERR_PTR(err);
205}
206
207static int erofs_fill_symlink(struct inode *inode, void *kaddr,
208 unsigned int m_pofs)
209{
210 struct erofs_inode *vi = EROFS_I(inode);
211 unsigned int bsz = i_blocksize(inode);
212 char *lnk;
213
214 /* if it cannot be handled with fast symlink scheme */
215 if (vi->datalayout != EROFS_INODE_FLAT_INLINE ||
216 inode->i_size >= bsz || inode->i_size < 0) {
217 inode->i_op = &erofs_symlink_iops;
218 return 0;
219 }
220
221 lnk = kmalloc(inode->i_size + 1, GFP_KERNEL);
222 if (!lnk)
223 return -ENOMEM;
224
225 m_pofs += vi->xattr_isize;
226 /* inline symlink data shouldn't cross block boundary */
227 if (m_pofs + inode->i_size > bsz) {
228 kfree(lnk);
229 erofs_err(inode->i_sb,
230 "inline data cross block boundary @ nid %llu",
231 vi->nid);
232 DBG_BUGON(1);
233 return -EFSCORRUPTED;
234 }
235 memcpy(lnk, kaddr + m_pofs, inode->i_size);
236 lnk[inode->i_size] = '\0';
237
238 inode->i_link = lnk;
239 inode->i_op = &erofs_fast_symlink_iops;
240 return 0;
241}
242
243static int erofs_fill_inode(struct inode *inode)
244{
245 struct erofs_inode *vi = EROFS_I(inode);
246 struct erofs_buf buf = __EROFS_BUF_INITIALIZER;
247 void *kaddr;
248 unsigned int ofs;
249 int err = 0;
250
251 trace_erofs_fill_inode(inode);
252
253 /* read inode base data from disk */
254 kaddr = erofs_read_inode(&buf, inode, &ofs);
255 if (IS_ERR(kaddr))
256 return PTR_ERR(kaddr);
257
258 /* setup the new inode */
259 switch (inode->i_mode & S_IFMT) {
260 case S_IFREG:
261 inode->i_op = &erofs_generic_iops;
262 if (erofs_inode_is_data_compressed(vi->datalayout))
263 inode->i_fop = &generic_ro_fops;
264 else
265 inode->i_fop = &erofs_file_fops;
266 break;
267 case S_IFDIR:
268 inode->i_op = &erofs_dir_iops;
269 inode->i_fop = &erofs_dir_fops;
270 inode_nohighmem(inode);
271 break;
272 case S_IFLNK:
273 err = erofs_fill_symlink(inode, kaddr, ofs);
274 if (err)
275 goto out_unlock;
276 inode_nohighmem(inode);
277 break;
278 case S_IFCHR:
279 case S_IFBLK:
280 case S_IFIFO:
281 case S_IFSOCK:
282 inode->i_op = &erofs_generic_iops;
283 init_special_inode(inode, inode->i_mode, inode->i_rdev);
284 goto out_unlock;
285 default:
286 err = -EFSCORRUPTED;
287 goto out_unlock;
288 }
289
290 if (erofs_inode_is_data_compressed(vi->datalayout)) {
291#ifdef CONFIG_EROFS_FS_ZIP
292 if (!erofs_is_fscache_mode(inode->i_sb) &&
293 inode->i_sb->s_blocksize_bits == PAGE_SHIFT) {
294 inode->i_mapping->a_ops = &z_erofs_aops;
295 err = 0;
296 goto out_unlock;
297 }
298#endif
299 err = -EOPNOTSUPP;
300 goto out_unlock;
301 }
302 inode->i_mapping->a_ops = &erofs_raw_access_aops;
303 mapping_set_large_folios(inode->i_mapping);
304#ifdef CONFIG_EROFS_FS_ONDEMAND
305 if (erofs_is_fscache_mode(inode->i_sb))
306 inode->i_mapping->a_ops = &erofs_fscache_access_aops;
307#endif
308
309out_unlock:
310 erofs_put_metabuf(&buf);
311 return err;
312}
313
314/*
315 * ino_t is 32-bits on 32-bit arch. We have to squash the 64-bit value down
316 * so that it will fit.
317 */
318static ino_t erofs_squash_ino(erofs_nid_t nid)
319{
320 ino_t ino = (ino_t)nid;
321
322 if (sizeof(ino_t) < sizeof(erofs_nid_t))
323 ino ^= nid >> (sizeof(erofs_nid_t) - sizeof(ino_t)) * 8;
324 return ino;
325}
326
327static int erofs_iget5_eq(struct inode *inode, void *opaque)
328{
329 return EROFS_I(inode)->nid == *(erofs_nid_t *)opaque;
330}
331
332static int erofs_iget5_set(struct inode *inode, void *opaque)
333{
334 const erofs_nid_t nid = *(erofs_nid_t *)opaque;
335
336 inode->i_ino = erofs_squash_ino(nid);
337 EROFS_I(inode)->nid = nid;
338 return 0;
339}
340
341struct inode *erofs_iget(struct super_block *sb, erofs_nid_t nid)
342{
343 struct inode *inode;
344
345 inode = iget5_locked(sb, erofs_squash_ino(nid), erofs_iget5_eq,
346 erofs_iget5_set, &nid);
347 if (!inode)
348 return ERR_PTR(-ENOMEM);
349
350 if (inode->i_state & I_NEW) {
351 int err = erofs_fill_inode(inode);
352
353 if (err) {
354 iget_failed(inode);
355 return ERR_PTR(err);
356 }
357 unlock_new_inode(inode);
358 }
359 return inode;
360}
361
362int erofs_getattr(struct mnt_idmap *idmap, const struct path *path,
363 struct kstat *stat, u32 request_mask,
364 unsigned int query_flags)
365{
366 struct inode *const inode = d_inode(path->dentry);
367
368 if (erofs_inode_is_data_compressed(EROFS_I(inode)->datalayout))
369 stat->attributes |= STATX_ATTR_COMPRESSED;
370
371 stat->attributes |= STATX_ATTR_IMMUTABLE;
372 stat->attributes_mask |= (STATX_ATTR_COMPRESSED |
373 STATX_ATTR_IMMUTABLE);
374
375 generic_fillattr(idmap, inode, stat);
376 return 0;
377}
378
379const struct inode_operations erofs_generic_iops = {
380 .getattr = erofs_getattr,
381 .listxattr = erofs_listxattr,
382 .get_inode_acl = erofs_get_acl,
383 .fiemap = erofs_fiemap,
384};
385
386const struct inode_operations erofs_symlink_iops = {
387 .get_link = page_get_link,
388 .getattr = erofs_getattr,
389 .listxattr = erofs_listxattr,
390 .get_inode_acl = erofs_get_acl,
391};
392
393const struct inode_operations erofs_fast_symlink_iops = {
394 .get_link = simple_get_link,
395 .getattr = erofs_getattr,
396 .listxattr = erofs_listxattr,
397 .get_inode_acl = erofs_get_acl,
398};