1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2017-2018 HUAWEI, Inc.
4 * https://www.huawei.com/
5 * Created by Gao Xiang <gaoxiang25@huawei.com>
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
127 kfree(copied);
128 break;
129 case EROFS_INODE_LAYOUT_COMPACT:
130 vi->inode_isize = sizeof(struct erofs_inode_compact);
131 *ofs += vi->inode_isize;
132 vi->xattr_isize = erofs_xattr_ibody_size(dic->i_xattr_icount);
133
134 inode->i_mode = le16_to_cpu(dic->i_mode);
135 switch (inode->i_mode & S_IFMT) {
136 case S_IFREG:
137 case S_IFDIR:
138 case S_IFLNK:
139 vi->raw_blkaddr = le32_to_cpu(dic->i_u.raw_blkaddr);
140 break;
141 case S_IFCHR:
142 case S_IFBLK:
143 inode->i_rdev =
144 new_decode_dev(le32_to_cpu(dic->i_u.rdev));
145 break;
146 case S_IFIFO:
147 case S_IFSOCK:
148 inode->i_rdev = 0;
149 break;
150 default:
151 goto bogusimode;
152 }
153 i_uid_write(inode, le16_to_cpu(dic->i_uid));
154 i_gid_write(inode, le16_to_cpu(dic->i_gid));
155 set_nlink(inode, le16_to_cpu(dic->i_nlink));
156
157 /* use build time for compact inodes */
158 inode->i_ctime.tv_sec = sbi->build_time;
159 inode->i_ctime.tv_nsec = sbi->build_time_nsec;
160
161 inode->i_size = le32_to_cpu(dic->i_size);
162 if (erofs_inode_is_data_compressed(vi->datalayout))
163 nblks = le32_to_cpu(dic->i_u.compressed_blocks);
164 break;
165 default:
166 erofs_err(inode->i_sb,
167 "unsupported on-disk inode version %u of nid %llu",
168 erofs_inode_version(ifmt), vi->nid);
169 err = -EOPNOTSUPP;
170 goto err_out;
171 }
172
173 inode->i_mtime.tv_sec = inode->i_ctime.tv_sec;
174 inode->i_atime.tv_sec = inode->i_ctime.tv_sec;
175 inode->i_mtime.tv_nsec = inode->i_ctime.tv_nsec;
176 inode->i_atime.tv_nsec = inode->i_ctime.tv_nsec;
177
178 if (!nblks)
179 /* measure inode.i_blocks as generic filesystems */
180 inode->i_blocks = roundup(inode->i_size, EROFS_BLKSIZ) >> 9;
181 else
182 inode->i_blocks = nblks << LOG_SECTORS_PER_BLOCK;
183 return page;
184
185 bogusimode:
186 erofs_err(inode->i_sb, "bogus i_mode (%o) @ nid %llu",
187 inode->i_mode, vi->nid);
188 err = -EFSCORRUPTED;
189 err_out:
190 DBG_BUGON(1);
191 kfree(copied);
192 unlock_page(page);
193 put_page(page);
194 return ERR_PTR(err);
195 }
196
erofs_fill_symlink(struct inode * inode,void * data,unsigned int m_pofs)197 static int erofs_fill_symlink(struct inode *inode, void *data,
198 unsigned int m_pofs)
199 {
200 struct erofs_inode *vi = EROFS_I(inode);
201 char *lnk;
202
203 /* if it cannot be handled with fast symlink scheme */
204 if (vi->datalayout != EROFS_INODE_FLAT_INLINE ||
205 inode->i_size >= PAGE_SIZE) {
206 inode->i_op = &erofs_symlink_iops;
207 return 0;
208 }
209
210 lnk = kmalloc(inode->i_size + 1, GFP_KERNEL);
211 if (!lnk)
212 return -ENOMEM;
213
214 m_pofs += vi->xattr_isize;
215 /* inline symlink data shouldn't cross page boundary as well */
216 if (m_pofs + inode->i_size > PAGE_SIZE) {
217 kfree(lnk);
218 erofs_err(inode->i_sb,
219 "inline data cross block boundary @ nid %llu",
220 vi->nid);
221 DBG_BUGON(1);
222 return -EFSCORRUPTED;
223 }
224
225 memcpy(lnk, data + m_pofs, inode->i_size);
226 lnk[inode->i_size] = '\0';
227
228 inode->i_link = lnk;
229 inode->i_op = &erofs_fast_symlink_iops;
230 return 0;
231 }
232
erofs_fill_inode(struct inode * inode,int isdir)233 static int erofs_fill_inode(struct inode *inode, int isdir)
234 {
235 struct erofs_inode *vi = EROFS_I(inode);
236 struct page *page;
237 unsigned int ofs;
238 int err = 0;
239
240 trace_erofs_fill_inode(inode, isdir);
241
242 /* read inode base data from disk */
243 page = erofs_read_inode(inode, &ofs);
244 if (IS_ERR(page))
245 return PTR_ERR(page);
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 inode->i_fop = &generic_ro_fops;
252 break;
253 case S_IFDIR:
254 inode->i_op = &erofs_dir_iops;
255 inode->i_fop = &erofs_dir_fops;
256 break;
257 case S_IFLNK:
258 err = erofs_fill_symlink(inode, page_address(page), ofs);
259 if (err)
260 goto out_unlock;
261 inode_nohighmem(inode);
262 break;
263 case S_IFCHR:
264 case S_IFBLK:
265 case S_IFIFO:
266 case S_IFSOCK:
267 inode->i_op = &erofs_generic_iops;
268 init_special_inode(inode, inode->i_mode, inode->i_rdev);
269 goto out_unlock;
270 default:
271 err = -EFSCORRUPTED;
272 goto out_unlock;
273 }
274
275 if (erofs_inode_is_data_compressed(vi->datalayout)) {
276 err = z_erofs_fill_inode(inode);
277 goto out_unlock;
278 }
279 inode->i_mapping->a_ops = &erofs_raw_access_aops;
280
281 out_unlock:
282 unlock_page(page);
283 put_page(page);
284 return err;
285 }
286
287 /*
288 * erofs nid is 64bits, but i_ino is 'unsigned long', therefore
289 * we should do more for 32-bit platform to find the right inode.
290 */
erofs_ilookup_test_actor(struct inode * inode,void * opaque)291 static int erofs_ilookup_test_actor(struct inode *inode, void *opaque)
292 {
293 const erofs_nid_t nid = *(erofs_nid_t *)opaque;
294
295 return EROFS_I(inode)->nid == nid;
296 }
297
erofs_iget_set_actor(struct inode * inode,void * opaque)298 static int erofs_iget_set_actor(struct inode *inode, void *opaque)
299 {
300 const erofs_nid_t nid = *(erofs_nid_t *)opaque;
301
302 inode->i_ino = erofs_inode_hash(nid);
303 return 0;
304 }
305
erofs_iget_locked(struct super_block * sb,erofs_nid_t nid)306 static inline struct inode *erofs_iget_locked(struct super_block *sb,
307 erofs_nid_t nid)
308 {
309 const unsigned long hashval = erofs_inode_hash(nid);
310
311 return iget5_locked(sb, hashval, erofs_ilookup_test_actor,
312 erofs_iget_set_actor, &nid);
313 }
314
erofs_iget(struct super_block * sb,erofs_nid_t nid,bool isdir)315 struct inode *erofs_iget(struct super_block *sb,
316 erofs_nid_t nid,
317 bool isdir)
318 {
319 struct inode *inode = erofs_iget_locked(sb, nid);
320
321 if (!inode)
322 return ERR_PTR(-ENOMEM);
323
324 if (inode->i_state & I_NEW) {
325 int err;
326 struct erofs_inode *vi = EROFS_I(inode);
327
328 vi->nid = nid;
329
330 err = erofs_fill_inode(inode, isdir);
331 if (!err)
332 unlock_new_inode(inode);
333 else {
334 iget_failed(inode);
335 inode = ERR_PTR(err);
336 }
337 }
338 return inode;
339 }
340
erofs_getattr(const struct path * path,struct kstat * stat,u32 request_mask,unsigned int query_flags)341 int erofs_getattr(const struct path *path, struct kstat *stat,
342 u32 request_mask, unsigned int query_flags)
343 {
344 struct inode *const inode = d_inode(path->dentry);
345
346 if (erofs_inode_is_data_compressed(EROFS_I(inode)->datalayout))
347 stat->attributes |= STATX_ATTR_COMPRESSED;
348
349 stat->attributes |= STATX_ATTR_IMMUTABLE;
350 stat->attributes_mask |= (STATX_ATTR_COMPRESSED |
351 STATX_ATTR_IMMUTABLE);
352
353 generic_fillattr(inode, stat);
354 return 0;
355 }
356
357 const struct inode_operations erofs_generic_iops = {
358 .getattr = erofs_getattr,
359 .listxattr = erofs_listxattr,
360 .get_acl = erofs_get_acl,
361 };
362
363 const struct inode_operations erofs_symlink_iops = {
364 .get_link = page_get_link,
365 .getattr = erofs_getattr,
366 .listxattr = erofs_listxattr,
367 .get_acl = erofs_get_acl,
368 };
369
370 const struct inode_operations erofs_fast_symlink_iops = {
371 .get_link = simple_get_link,
372 .getattr = erofs_getattr,
373 .listxattr = erofs_listxattr,
374 .get_acl = erofs_get_acl,
375 };
376
377