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