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
erofs_read_inode(struct erofs_buf * buf,struct inode * inode,unsigned int * ofs)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
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_set_ctime(inode, le64_to_cpu(die->i_mtime),
109 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_set_ctime(inode, sbi->build_time, sbi->build_time_nsec);
152
153 inode->i_size = le32_to_cpu(dic->i_size);
154 if (erofs_inode_is_data_compressed(vi->datalayout))
155 nblks = le32_to_cpu(dic->i_u.compressed_blocks);
156 else if (vi->datalayout == EROFS_INODE_CHUNK_BASED)
157 vi->chunkformat = le16_to_cpu(dic->i_u.c.format);
158 break;
159 default:
160 erofs_err(inode->i_sb,
161 "unsupported on-disk inode version %u of nid %llu",
162 erofs_inode_version(ifmt), vi->nid);
163 err = -EOPNOTSUPP;
164 goto err_out;
165 }
166
167 if (vi->datalayout == EROFS_INODE_CHUNK_BASED) {
168 if (vi->chunkformat & ~EROFS_CHUNK_FORMAT_ALL) {
169 erofs_err(inode->i_sb,
170 "unsupported chunk format %x of nid %llu",
171 vi->chunkformat, vi->nid);
172 err = -EOPNOTSUPP;
173 goto err_out;
174 }
175 vi->chunkbits = sb->s_blocksize_bits +
176 (vi->chunkformat & EROFS_CHUNK_FORMAT_BLKBITS_MASK);
177 }
178 inode->i_mtime = inode->i_atime = inode_get_ctime(inode);
179
180 inode->i_flags &= ~S_DAX;
181 if (test_opt(&sbi->opt, DAX_ALWAYS) && S_ISREG(inode->i_mode) &&
182 (vi->datalayout == EROFS_INODE_FLAT_PLAIN ||
183 vi->datalayout == EROFS_INODE_CHUNK_BASED))
184 inode->i_flags |= S_DAX;
185
186 if (!nblks)
187 /* measure inode.i_blocks as generic filesystems */
188 inode->i_blocks = round_up(inode->i_size, sb->s_blocksize) >> 9;
189 else
190 inode->i_blocks = nblks << (sb->s_blocksize_bits - 9);
191 return kaddr;
192
193 bogusimode:
194 erofs_err(inode->i_sb, "bogus i_mode (%o) @ nid %llu",
195 inode->i_mode, vi->nid);
196 err = -EFSCORRUPTED;
197 err_out:
198 DBG_BUGON(1);
199 kfree(copied);
200 erofs_put_metabuf(buf);
201 return ERR_PTR(err);
202 }
203
erofs_fill_symlink(struct inode * inode,void * kaddr,unsigned int m_pofs)204 static int erofs_fill_symlink(struct inode *inode, void *kaddr,
205 unsigned int m_pofs)
206 {
207 struct erofs_inode *vi = EROFS_I(inode);
208 loff_t off;
209 char *lnk;
210
211 m_pofs += vi->xattr_isize;
212 /* check if it cannot be handled with fast symlink scheme */
213 if (vi->datalayout != EROFS_INODE_FLAT_INLINE || inode->i_size < 0 ||
214 check_add_overflow(m_pofs, inode->i_size, &off) ||
215 off > i_blocksize(inode)) {
216 inode->i_op = &erofs_symlink_iops;
217 return 0;
218 }
219
220 lnk = kmalloc(inode->i_size + 1, GFP_KERNEL);
221 if (!lnk)
222 return -ENOMEM;
223
224 memcpy(lnk, kaddr + m_pofs, inode->i_size);
225 lnk[inode->i_size] = '\0';
226
227 inode->i_link = lnk;
228 inode->i_op = &erofs_fast_symlink_iops;
229 return 0;
230 }
231
erofs_fill_inode(struct inode * inode)232 static int erofs_fill_inode(struct inode *inode)
233 {
234 struct erofs_inode *vi = EROFS_I(inode);
235 struct erofs_buf buf = __EROFS_BUF_INITIALIZER;
236 void *kaddr;
237 unsigned int ofs;
238 int err = 0;
239
240 trace_erofs_fill_inode(inode);
241
242 /* read inode base data from disk */
243 kaddr = erofs_read_inode(&buf, inode, &ofs);
244 if (IS_ERR(kaddr))
245 return PTR_ERR(kaddr);
246
247 /* setup the new inode */
248 switch (inode->i_mode & S_IFMT) {
249 case S_IFREG:
250 inode->i_op = &erofs_generic_iops;
251 if (erofs_inode_is_data_compressed(vi->datalayout))
252 inode->i_fop = &generic_ro_fops;
253 else
254 inode->i_fop = &erofs_file_fops;
255 break;
256 case S_IFDIR:
257 inode->i_op = &erofs_dir_iops;
258 inode->i_fop = &erofs_dir_fops;
259 inode_nohighmem(inode);
260 break;
261 case S_IFLNK:
262 err = erofs_fill_symlink(inode, kaddr, ofs);
263 if (err)
264 goto out_unlock;
265 inode_nohighmem(inode);
266 break;
267 case S_IFCHR:
268 case S_IFBLK:
269 case S_IFIFO:
270 case S_IFSOCK:
271 inode->i_op = &erofs_generic_iops;
272 init_special_inode(inode, inode->i_mode, inode->i_rdev);
273 goto out_unlock;
274 default:
275 err = -EFSCORRUPTED;
276 goto out_unlock;
277 }
278
279 if (erofs_inode_is_data_compressed(vi->datalayout)) {
280 #ifdef CONFIG_EROFS_FS_ZIP
281 if (!erofs_is_fscache_mode(inode->i_sb) &&
282 inode->i_sb->s_blocksize_bits == PAGE_SHIFT) {
283 inode->i_mapping->a_ops = &z_erofs_aops;
284 err = 0;
285 goto out_unlock;
286 }
287 #endif
288 err = -EOPNOTSUPP;
289 goto out_unlock;
290 }
291 inode->i_mapping->a_ops = &erofs_raw_access_aops;
292 mapping_set_large_folios(inode->i_mapping);
293 #ifdef CONFIG_EROFS_FS_ONDEMAND
294 if (erofs_is_fscache_mode(inode->i_sb))
295 inode->i_mapping->a_ops = &erofs_fscache_access_aops;
296 #endif
297
298 out_unlock:
299 erofs_put_metabuf(&buf);
300 return err;
301 }
302
303 /*
304 * ino_t is 32-bits on 32-bit arch. We have to squash the 64-bit value down
305 * so that it will fit.
306 */
erofs_squash_ino(erofs_nid_t nid)307 static ino_t erofs_squash_ino(erofs_nid_t nid)
308 {
309 ino_t ino = (ino_t)nid;
310
311 if (sizeof(ino_t) < sizeof(erofs_nid_t))
312 ino ^= nid >> (sizeof(erofs_nid_t) - sizeof(ino_t)) * 8;
313 return ino;
314 }
315
erofs_iget5_eq(struct inode * inode,void * opaque)316 static int erofs_iget5_eq(struct inode *inode, void *opaque)
317 {
318 return EROFS_I(inode)->nid == *(erofs_nid_t *)opaque;
319 }
320
erofs_iget5_set(struct inode * inode,void * opaque)321 static int erofs_iget5_set(struct inode *inode, void *opaque)
322 {
323 const erofs_nid_t nid = *(erofs_nid_t *)opaque;
324
325 inode->i_ino = erofs_squash_ino(nid);
326 EROFS_I(inode)->nid = nid;
327 return 0;
328 }
329
erofs_iget(struct super_block * sb,erofs_nid_t nid)330 struct inode *erofs_iget(struct super_block *sb, erofs_nid_t nid)
331 {
332 struct inode *inode;
333
334 inode = iget5_locked(sb, erofs_squash_ino(nid), erofs_iget5_eq,
335 erofs_iget5_set, &nid);
336 if (!inode)
337 return ERR_PTR(-ENOMEM);
338
339 if (inode->i_state & I_NEW) {
340 int err = erofs_fill_inode(inode);
341
342 if (err) {
343 iget_failed(inode);
344 return ERR_PTR(err);
345 }
346 unlock_new_inode(inode);
347 }
348 return inode;
349 }
350
erofs_getattr(struct mnt_idmap * idmap,const struct path * path,struct kstat * stat,u32 request_mask,unsigned int query_flags)351 int erofs_getattr(struct mnt_idmap *idmap, const struct path *path,
352 struct kstat *stat, u32 request_mask,
353 unsigned int query_flags)
354 {
355 struct inode *const inode = d_inode(path->dentry);
356
357 if (erofs_inode_is_data_compressed(EROFS_I(inode)->datalayout))
358 stat->attributes |= STATX_ATTR_COMPRESSED;
359
360 stat->attributes |= STATX_ATTR_IMMUTABLE;
361 stat->attributes_mask |= (STATX_ATTR_COMPRESSED |
362 STATX_ATTR_IMMUTABLE);
363
364 generic_fillattr(idmap, request_mask, inode, stat);
365 return 0;
366 }
367
368 const struct inode_operations erofs_generic_iops = {
369 .getattr = erofs_getattr,
370 .listxattr = erofs_listxattr,
371 .get_inode_acl = erofs_get_acl,
372 .fiemap = erofs_fiemap,
373 };
374
375 const struct inode_operations erofs_symlink_iops = {
376 .get_link = page_get_link,
377 .getattr = erofs_getattr,
378 .listxattr = erofs_listxattr,
379 .get_inode_acl = erofs_get_acl,
380 };
381
382 const struct inode_operations erofs_fast_symlink_iops = {
383 .get_link = simple_get_link,
384 .getattr = erofs_getattr,
385 .listxattr = erofs_listxattr,
386 .get_inode_acl = erofs_get_acl,
387 };
388