GNU Linux-libre 5.19-rc6-gnu
[releases.git] / fs / erofs / inode.c
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 static 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 = iloc(sbi, vi->nid);
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(inode_loc);
27         *ofs = erofs_blkoff(inode_loc);
28
29         erofs_dbg("%s, reading inode nid %llu at %u of blkaddr %u",
30                   __func__, vi->nid, *ofs, blkaddr);
31
32         kaddr = erofs_read_metabuf(buf, sb, blkaddr, EROFS_KMAP);
33         if (IS_ERR(kaddr)) {
34                 erofs_err(sb, "failed to get inode (nid: %llu) page, err %ld",
35                           vi->nid, PTR_ERR(kaddr));
36                 return kaddr;
37         }
38
39         dic = kaddr + *ofs;
40         ifmt = le16_to_cpu(dic->i_format);
41
42         if (ifmt & ~EROFS_I_ALL) {
43                 erofs_err(inode->i_sb, "unsupported i_format %u of nid %llu",
44                           ifmt, vi->nid);
45                 err = -EOPNOTSUPP;
46                 goto err_out;
47         }
48
49         vi->datalayout = erofs_inode_datalayout(ifmt);
50         if (vi->datalayout >= EROFS_INODE_DATALAYOUT_MAX) {
51                 erofs_err(inode->i_sb, "unsupported datalayout %u of nid %llu",
52                           vi->datalayout, vi->nid);
53                 err = -EOPNOTSUPP;
54                 goto err_out;
55         }
56
57         switch (erofs_inode_version(ifmt)) {
58         case EROFS_INODE_LAYOUT_EXTENDED:
59                 vi->inode_isize = sizeof(struct erofs_inode_extended);
60                 /* check if the extended inode acrosses block boundary */
61                 if (*ofs + vi->inode_isize <= EROFS_BLKSIZ) {
62                         *ofs += vi->inode_isize;
63                         die = (struct erofs_inode_extended *)dic;
64                 } else {
65                         const unsigned int gotten = EROFS_BLKSIZ - *ofs;
66
67                         copied = kmalloc(vi->inode_isize, GFP_NOFS);
68                         if (!copied) {
69                                 err = -ENOMEM;
70                                 goto err_out;
71                         }
72                         memcpy(copied, dic, gotten);
73                         kaddr = erofs_read_metabuf(buf, sb, blkaddr + 1,
74                                                    EROFS_KMAP);
75                         if (IS_ERR(kaddr)) {
76                                 erofs_err(sb, "failed to get inode payload block (nid: %llu), err %ld",
77                                           vi->nid, PTR_ERR(kaddr));
78                                 kfree(copied);
79                                 return kaddr;
80                         }
81                         *ofs = vi->inode_isize - gotten;
82                         memcpy((u8 *)copied + gotten, kaddr, *ofs);
83                         die = copied;
84                 }
85                 vi->xattr_isize = erofs_xattr_ibody_size(die->i_xattr_icount);
86
87                 inode->i_mode = le16_to_cpu(die->i_mode);
88                 switch (inode->i_mode & S_IFMT) {
89                 case S_IFREG:
90                 case S_IFDIR:
91                 case S_IFLNK:
92                         vi->raw_blkaddr = le32_to_cpu(die->i_u.raw_blkaddr);
93                         break;
94                 case S_IFCHR:
95                 case S_IFBLK:
96                         inode->i_rdev =
97                                 new_decode_dev(le32_to_cpu(die->i_u.rdev));
98                         break;
99                 case S_IFIFO:
100                 case S_IFSOCK:
101                         inode->i_rdev = 0;
102                         break;
103                 default:
104                         goto bogusimode;
105                 }
106                 i_uid_write(inode, le32_to_cpu(die->i_uid));
107                 i_gid_write(inode, le32_to_cpu(die->i_gid));
108                 set_nlink(inode, le32_to_cpu(die->i_nlink));
109
110                 /* extended inode has its own timestamp */
111                 inode->i_ctime.tv_sec = le64_to_cpu(die->i_mtime);
112                 inode->i_ctime.tv_nsec = le32_to_cpu(die->i_mtime_nsec);
113
114                 inode->i_size = le64_to_cpu(die->i_size);
115
116                 /* total blocks for compressed files */
117                 if (erofs_inode_is_data_compressed(vi->datalayout))
118                         nblks = le32_to_cpu(die->i_u.compressed_blocks);
119                 else if (vi->datalayout == EROFS_INODE_CHUNK_BASED)
120                         /* fill chunked inode summary info */
121                         vi->chunkformat = le16_to_cpu(die->i_u.c.format);
122                 kfree(copied);
123                 copied = NULL;
124                 break;
125         case EROFS_INODE_LAYOUT_COMPACT:
126                 vi->inode_isize = sizeof(struct erofs_inode_compact);
127                 *ofs += vi->inode_isize;
128                 vi->xattr_isize = erofs_xattr_ibody_size(dic->i_xattr_icount);
129
130                 inode->i_mode = le16_to_cpu(dic->i_mode);
131                 switch (inode->i_mode & S_IFMT) {
132                 case S_IFREG:
133                 case S_IFDIR:
134                 case S_IFLNK:
135                         vi->raw_blkaddr = le32_to_cpu(dic->i_u.raw_blkaddr);
136                         break;
137                 case S_IFCHR:
138                 case S_IFBLK:
139                         inode->i_rdev =
140                                 new_decode_dev(le32_to_cpu(dic->i_u.rdev));
141                         break;
142                 case S_IFIFO:
143                 case S_IFSOCK:
144                         inode->i_rdev = 0;
145                         break;
146                 default:
147                         goto bogusimode;
148                 }
149                 i_uid_write(inode, le16_to_cpu(dic->i_uid));
150                 i_gid_write(inode, le16_to_cpu(dic->i_gid));
151                 set_nlink(inode, le16_to_cpu(dic->i_nlink));
152
153                 /* use build time for compact inodes */
154                 inode->i_ctime.tv_sec = sbi->build_time;
155                 inode->i_ctime.tv_nsec = sbi->build_time_nsec;
156
157                 inode->i_size = le32_to_cpu(dic->i_size);
158                 if (erofs_inode_is_data_compressed(vi->datalayout))
159                         nblks = le32_to_cpu(dic->i_u.compressed_blocks);
160                 else if (vi->datalayout == EROFS_INODE_CHUNK_BASED)
161                         vi->chunkformat = le16_to_cpu(dic->i_u.c.format);
162                 break;
163         default:
164                 erofs_err(inode->i_sb,
165                           "unsupported on-disk inode version %u of nid %llu",
166                           erofs_inode_version(ifmt), vi->nid);
167                 err = -EOPNOTSUPP;
168                 goto err_out;
169         }
170
171         if (vi->datalayout == EROFS_INODE_CHUNK_BASED) {
172                 if (vi->chunkformat & ~EROFS_CHUNK_FORMAT_ALL) {
173                         erofs_err(inode->i_sb,
174                                   "unsupported chunk format %x of nid %llu",
175                                   vi->chunkformat, vi->nid);
176                         err = -EOPNOTSUPP;
177                         goto err_out;
178                 }
179                 vi->chunkbits = LOG_BLOCK_SIZE +
180                         (vi->chunkformat & EROFS_CHUNK_FORMAT_BLKBITS_MASK);
181         }
182         inode->i_mtime.tv_sec = inode->i_ctime.tv_sec;
183         inode->i_atime.tv_sec = inode->i_ctime.tv_sec;
184         inode->i_mtime.tv_nsec = inode->i_ctime.tv_nsec;
185         inode->i_atime.tv_nsec = inode->i_ctime.tv_nsec;
186
187         inode->i_flags &= ~S_DAX;
188         if (test_opt(&sbi->opt, DAX_ALWAYS) && S_ISREG(inode->i_mode) &&
189             vi->datalayout == EROFS_INODE_FLAT_PLAIN)
190                 inode->i_flags |= S_DAX;
191         if (!nblks)
192                 /* measure inode.i_blocks as generic filesystems */
193                 inode->i_blocks = roundup(inode->i_size, EROFS_BLKSIZ) >> 9;
194         else
195                 inode->i_blocks = nblks << LOG_SECTORS_PER_BLOCK;
196         return kaddr;
197
198 bogusimode:
199         erofs_err(inode->i_sb, "bogus i_mode (%o) @ nid %llu",
200                   inode->i_mode, vi->nid);
201         err = -EFSCORRUPTED;
202 err_out:
203         DBG_BUGON(1);
204         kfree(copied);
205         erofs_put_metabuf(buf);
206         return ERR_PTR(err);
207 }
208
209 static int erofs_fill_symlink(struct inode *inode, void *kaddr,
210                               unsigned int m_pofs)
211 {
212         struct erofs_inode *vi = EROFS_I(inode);
213         char *lnk;
214
215         /* if it cannot be handled with fast symlink scheme */
216         if (vi->datalayout != EROFS_INODE_FLAT_INLINE ||
217             inode->i_size >= EROFS_BLKSIZ) {
218                 inode->i_op = &erofs_symlink_iops;
219                 return 0;
220         }
221
222         lnk = kmalloc(inode->i_size + 1, GFP_KERNEL);
223         if (!lnk)
224                 return -ENOMEM;
225
226         m_pofs += vi->xattr_isize;
227         /* inline symlink data shouldn't cross block boundary */
228         if (m_pofs + inode->i_size > EROFS_BLKSIZ) {
229                 kfree(lnk);
230                 erofs_err(inode->i_sb,
231                           "inline data cross block boundary @ nid %llu",
232                           vi->nid);
233                 DBG_BUGON(1);
234                 return -EFSCORRUPTED;
235         }
236         memcpy(lnk, kaddr + m_pofs, inode->i_size);
237         lnk[inode->i_size] = '\0';
238
239         inode->i_link = lnk;
240         inode->i_op = &erofs_fast_symlink_iops;
241         return 0;
242 }
243
244 static int erofs_fill_inode(struct inode *inode, int isdir)
245 {
246         struct erofs_inode *vi = EROFS_I(inode);
247         struct erofs_buf buf = __EROFS_BUF_INITIALIZER;
248         void *kaddr;
249         unsigned int ofs;
250         int err = 0;
251
252         trace_erofs_fill_inode(inode, isdir);
253
254         /* read inode base data from disk */
255         kaddr = erofs_read_inode(&buf, inode, &ofs);
256         if (IS_ERR(kaddr))
257                 return PTR_ERR(kaddr);
258
259         /* setup the new inode */
260         switch (inode->i_mode & S_IFMT) {
261         case S_IFREG:
262                 inode->i_op = &erofs_generic_iops;
263                 if (erofs_inode_is_data_compressed(vi->datalayout))
264                         inode->i_fop = &generic_ro_fops;
265                 else
266                         inode->i_fop = &erofs_file_fops;
267                 break;
268         case S_IFDIR:
269                 inode->i_op = &erofs_dir_iops;
270                 inode->i_fop = &erofs_dir_fops;
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                 if (!erofs_is_fscache_mode(inode->i_sb))
292                         err = z_erofs_fill_inode(inode);
293                 else
294                         err = -EOPNOTSUPP;
295                 goto out_unlock;
296         }
297         inode->i_mapping->a_ops = &erofs_raw_access_aops;
298 #ifdef CONFIG_EROFS_FS_ONDEMAND
299         if (erofs_is_fscache_mode(inode->i_sb))
300                 inode->i_mapping->a_ops = &erofs_fscache_access_aops;
301 #endif
302
303 out_unlock:
304         erofs_put_metabuf(&buf);
305         return err;
306 }
307
308 /*
309  * erofs nid is 64bits, but i_ino is 'unsigned long', therefore
310  * we should do more for 32-bit platform to find the right inode.
311  */
312 static int erofs_ilookup_test_actor(struct inode *inode, void *opaque)
313 {
314         const erofs_nid_t nid = *(erofs_nid_t *)opaque;
315
316         return EROFS_I(inode)->nid == nid;
317 }
318
319 static int erofs_iget_set_actor(struct inode *inode, void *opaque)
320 {
321         const erofs_nid_t nid = *(erofs_nid_t *)opaque;
322
323         inode->i_ino = erofs_inode_hash(nid);
324         return 0;
325 }
326
327 static inline struct inode *erofs_iget_locked(struct super_block *sb,
328                                               erofs_nid_t nid)
329 {
330         const unsigned long hashval = erofs_inode_hash(nid);
331
332         return iget5_locked(sb, hashval, erofs_ilookup_test_actor,
333                 erofs_iget_set_actor, &nid);
334 }
335
336 struct inode *erofs_iget(struct super_block *sb,
337                          erofs_nid_t nid,
338                          bool isdir)
339 {
340         struct inode *inode = erofs_iget_locked(sb, nid);
341
342         if (!inode)
343                 return ERR_PTR(-ENOMEM);
344
345         if (inode->i_state & I_NEW) {
346                 int err;
347                 struct erofs_inode *vi = EROFS_I(inode);
348
349                 vi->nid = nid;
350
351                 err = erofs_fill_inode(inode, isdir);
352                 if (!err)
353                         unlock_new_inode(inode);
354                 else {
355                         iget_failed(inode);
356                         inode = ERR_PTR(err);
357                 }
358         }
359         return inode;
360 }
361
362 int erofs_getattr(struct user_namespace *mnt_userns, 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(mnt_userns, inode, stat);
376         return 0;
377 }
378
379 const struct inode_operations erofs_generic_iops = {
380         .getattr = erofs_getattr,
381         .listxattr = erofs_listxattr,
382         .get_acl = erofs_get_acl,
383         .fiemap = erofs_fiemap,
384 };
385
386 const struct inode_operations erofs_symlink_iops = {
387         .get_link = page_get_link,
388         .getattr = erofs_getattr,
389         .listxattr = erofs_listxattr,
390         .get_acl = erofs_get_acl,
391 };
392
393 const struct inode_operations erofs_fast_symlink_iops = {
394         .get_link = simple_get_link,
395         .getattr = erofs_getattr,
396         .listxattr = erofs_listxattr,
397         .get_acl = erofs_get_acl,
398 };