1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * This file contains vfs inode ops for the 9P2000 protocol. |
4 | * |
5 | * Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com> |
6 | * Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov> |
7 | */ |
8 | |
9 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
10 | |
11 | #include <linux/module.h> |
12 | #include <linux/errno.h> |
13 | #include <linux/fs.h> |
14 | #include <linux/file.h> |
15 | #include <linux/pagemap.h> |
16 | #include <linux/stat.h> |
17 | #include <linux/string.h> |
18 | #include <linux/namei.h> |
19 | #include <linux/sched.h> |
20 | #include <linux/slab.h> |
21 | #include <linux/xattr.h> |
22 | #include <linux/posix_acl.h> |
23 | #include <net/9p/9p.h> |
24 | #include <net/9p/client.h> |
25 | |
26 | #include "v9fs.h" |
27 | #include "v9fs_vfs.h" |
28 | #include "fid.h" |
29 | #include "cache.h" |
30 | #include "xattr.h" |
31 | #include "acl.h" |
32 | |
33 | static const struct inode_operations v9fs_dir_inode_operations; |
34 | static const struct inode_operations v9fs_dir_inode_operations_dotu; |
35 | static const struct inode_operations v9fs_file_inode_operations; |
36 | static const struct inode_operations v9fs_symlink_inode_operations; |
37 | |
38 | /** |
39 | * unixmode2p9mode - convert unix mode bits to plan 9 |
40 | * @v9ses: v9fs session information |
41 | * @mode: mode to convert |
42 | * |
43 | */ |
44 | |
45 | static u32 unixmode2p9mode(struct v9fs_session_info *v9ses, umode_t mode) |
46 | { |
47 | int res; |
48 | |
49 | res = mode & 0777; |
50 | if (S_ISDIR(mode)) |
51 | res |= P9_DMDIR; |
52 | if (v9fs_proto_dotu(v9ses)) { |
53 | if (v9ses->nodev == 0) { |
54 | if (S_ISSOCK(mode)) |
55 | res |= P9_DMSOCKET; |
56 | if (S_ISFIFO(mode)) |
57 | res |= P9_DMNAMEDPIPE; |
58 | if (S_ISBLK(mode)) |
59 | res |= P9_DMDEVICE; |
60 | if (S_ISCHR(mode)) |
61 | res |= P9_DMDEVICE; |
62 | } |
63 | |
64 | if ((mode & S_ISUID) == S_ISUID) |
65 | res |= P9_DMSETUID; |
66 | if ((mode & S_ISGID) == S_ISGID) |
67 | res |= P9_DMSETGID; |
68 | if ((mode & S_ISVTX) == S_ISVTX) |
69 | res |= P9_DMSETVTX; |
70 | } |
71 | return res; |
72 | } |
73 | |
74 | /** |
75 | * p9mode2perm- convert plan9 mode bits to unix permission bits |
76 | * @v9ses: v9fs session information |
77 | * @stat: p9_wstat from which mode need to be derived |
78 | * |
79 | */ |
80 | static int p9mode2perm(struct v9fs_session_info *v9ses, |
81 | struct p9_wstat *stat) |
82 | { |
83 | int res; |
84 | int mode = stat->mode; |
85 | |
86 | res = mode & S_IALLUGO; |
87 | if (v9fs_proto_dotu(v9ses)) { |
88 | if ((mode & P9_DMSETUID) == P9_DMSETUID) |
89 | res |= S_ISUID; |
90 | |
91 | if ((mode & P9_DMSETGID) == P9_DMSETGID) |
92 | res |= S_ISGID; |
93 | |
94 | if ((mode & P9_DMSETVTX) == P9_DMSETVTX) |
95 | res |= S_ISVTX; |
96 | } |
97 | return res; |
98 | } |
99 | |
100 | /** |
101 | * p9mode2unixmode- convert plan9 mode bits to unix mode bits |
102 | * @v9ses: v9fs session information |
103 | * @stat: p9_wstat from which mode need to be derived |
104 | * @rdev: major number, minor number in case of device files. |
105 | * |
106 | */ |
107 | static umode_t p9mode2unixmode(struct v9fs_session_info *v9ses, |
108 | struct p9_wstat *stat, dev_t *rdev) |
109 | { |
110 | int res, r; |
111 | u32 mode = stat->mode; |
112 | |
113 | *rdev = 0; |
114 | res = p9mode2perm(v9ses, stat); |
115 | |
116 | if ((mode & P9_DMDIR) == P9_DMDIR) |
117 | res |= S_IFDIR; |
118 | else if ((mode & P9_DMSYMLINK) && (v9fs_proto_dotu(v9ses))) |
119 | res |= S_IFLNK; |
120 | else if ((mode & P9_DMSOCKET) && (v9fs_proto_dotu(v9ses)) |
121 | && (v9ses->nodev == 0)) |
122 | res |= S_IFSOCK; |
123 | else if ((mode & P9_DMNAMEDPIPE) && (v9fs_proto_dotu(v9ses)) |
124 | && (v9ses->nodev == 0)) |
125 | res |= S_IFIFO; |
126 | else if ((mode & P9_DMDEVICE) && (v9fs_proto_dotu(v9ses)) |
127 | && (v9ses->nodev == 0)) { |
128 | char type = 0; |
129 | int major = -1, minor = -1; |
130 | |
131 | r = sscanf(stat->extension, "%c %i %i" , &type, &major, &minor); |
132 | if (r != 3) { |
133 | p9_debug(P9_DEBUG_ERROR, |
134 | "invalid device string, umode will be bogus: %s\n" , |
135 | stat->extension); |
136 | return res; |
137 | } |
138 | switch (type) { |
139 | case 'c': |
140 | res |= S_IFCHR; |
141 | break; |
142 | case 'b': |
143 | res |= S_IFBLK; |
144 | break; |
145 | default: |
146 | p9_debug(P9_DEBUG_ERROR, "Unknown special type %c %s\n" , |
147 | type, stat->extension); |
148 | } |
149 | *rdev = MKDEV(major, minor); |
150 | } else |
151 | res |= S_IFREG; |
152 | |
153 | return res; |
154 | } |
155 | |
156 | /** |
157 | * v9fs_uflags2omode- convert posix open flags to plan 9 mode bits |
158 | * @uflags: flags to convert |
159 | * @extended: if .u extensions are active |
160 | */ |
161 | |
162 | int v9fs_uflags2omode(int uflags, int extended) |
163 | { |
164 | int ret; |
165 | |
166 | switch (uflags&3) { |
167 | default: |
168 | case O_RDONLY: |
169 | ret = P9_OREAD; |
170 | break; |
171 | |
172 | case O_WRONLY: |
173 | ret = P9_OWRITE; |
174 | break; |
175 | |
176 | case O_RDWR: |
177 | ret = P9_ORDWR; |
178 | break; |
179 | } |
180 | |
181 | if (extended) { |
182 | if (uflags & O_EXCL) |
183 | ret |= P9_OEXCL; |
184 | |
185 | if (uflags & O_APPEND) |
186 | ret |= P9_OAPPEND; |
187 | } |
188 | |
189 | return ret; |
190 | } |
191 | |
192 | /** |
193 | * v9fs_blank_wstat - helper function to setup a 9P stat structure |
194 | * @wstat: structure to initialize |
195 | * |
196 | */ |
197 | |
198 | void |
199 | v9fs_blank_wstat(struct p9_wstat *wstat) |
200 | { |
201 | wstat->type = ~0; |
202 | wstat->dev = ~0; |
203 | wstat->qid.type = ~0; |
204 | wstat->qid.version = ~0; |
205 | *((long long *)&wstat->qid.path) = ~0; |
206 | wstat->mode = ~0; |
207 | wstat->atime = ~0; |
208 | wstat->mtime = ~0; |
209 | wstat->length = ~0; |
210 | wstat->name = NULL; |
211 | wstat->uid = NULL; |
212 | wstat->gid = NULL; |
213 | wstat->muid = NULL; |
214 | wstat->n_uid = INVALID_UID; |
215 | wstat->n_gid = INVALID_GID; |
216 | wstat->n_muid = INVALID_UID; |
217 | wstat->extension = NULL; |
218 | } |
219 | |
220 | /** |
221 | * v9fs_alloc_inode - helper function to allocate an inode |
222 | * @sb: The superblock to allocate the inode from |
223 | */ |
224 | struct inode *v9fs_alloc_inode(struct super_block *sb) |
225 | { |
226 | struct v9fs_inode *v9inode; |
227 | |
228 | v9inode = alloc_inode_sb(sb, cache: v9fs_inode_cache, GFP_KERNEL); |
229 | if (!v9inode) |
230 | return NULL; |
231 | v9inode->cache_validity = 0; |
232 | mutex_init(&v9inode->v_mutex); |
233 | return &v9inode->netfs.inode; |
234 | } |
235 | |
236 | /** |
237 | * v9fs_free_inode - destroy an inode |
238 | * @inode: The inode to be freed |
239 | */ |
240 | |
241 | void v9fs_free_inode(struct inode *inode) |
242 | { |
243 | kmem_cache_free(s: v9fs_inode_cache, objp: V9FS_I(inode)); |
244 | } |
245 | |
246 | /* |
247 | * Set parameters for the netfs library |
248 | */ |
249 | static void v9fs_set_netfs_context(struct inode *inode) |
250 | { |
251 | struct v9fs_inode *v9inode = V9FS_I(inode); |
252 | netfs_inode_init(ctx: &v9inode->netfs, ops: &v9fs_req_ops); |
253 | } |
254 | |
255 | int v9fs_init_inode(struct v9fs_session_info *v9ses, |
256 | struct inode *inode, umode_t mode, dev_t rdev) |
257 | { |
258 | int err = 0; |
259 | |
260 | inode_init_owner(idmap: &nop_mnt_idmap, inode, NULL, mode); |
261 | inode->i_blocks = 0; |
262 | inode->i_rdev = rdev; |
263 | simple_inode_init_ts(inode); |
264 | inode->i_mapping->a_ops = &v9fs_addr_operations; |
265 | inode->i_private = NULL; |
266 | |
267 | switch (mode & S_IFMT) { |
268 | case S_IFIFO: |
269 | case S_IFBLK: |
270 | case S_IFCHR: |
271 | case S_IFSOCK: |
272 | if (v9fs_proto_dotl(v9ses)) { |
273 | inode->i_op = &v9fs_file_inode_operations_dotl; |
274 | } else if (v9fs_proto_dotu(v9ses)) { |
275 | inode->i_op = &v9fs_file_inode_operations; |
276 | } else { |
277 | p9_debug(P9_DEBUG_ERROR, |
278 | "special files without extended mode\n" ); |
279 | err = -EINVAL; |
280 | goto error; |
281 | } |
282 | init_special_inode(inode, inode->i_mode, inode->i_rdev); |
283 | break; |
284 | case S_IFREG: |
285 | if (v9fs_proto_dotl(v9ses)) { |
286 | inode->i_op = &v9fs_file_inode_operations_dotl; |
287 | inode->i_fop = &v9fs_file_operations_dotl; |
288 | } else { |
289 | inode->i_op = &v9fs_file_inode_operations; |
290 | inode->i_fop = &v9fs_file_operations; |
291 | } |
292 | |
293 | break; |
294 | case S_IFLNK: |
295 | if (!v9fs_proto_dotu(v9ses) && !v9fs_proto_dotl(v9ses)) { |
296 | p9_debug(P9_DEBUG_ERROR, |
297 | "extended modes used with legacy protocol\n" ); |
298 | err = -EINVAL; |
299 | goto error; |
300 | } |
301 | |
302 | if (v9fs_proto_dotl(v9ses)) |
303 | inode->i_op = &v9fs_symlink_inode_operations_dotl; |
304 | else |
305 | inode->i_op = &v9fs_symlink_inode_operations; |
306 | |
307 | break; |
308 | case S_IFDIR: |
309 | inc_nlink(inode); |
310 | if (v9fs_proto_dotl(v9ses)) |
311 | inode->i_op = &v9fs_dir_inode_operations_dotl; |
312 | else if (v9fs_proto_dotu(v9ses)) |
313 | inode->i_op = &v9fs_dir_inode_operations_dotu; |
314 | else |
315 | inode->i_op = &v9fs_dir_inode_operations; |
316 | |
317 | if (v9fs_proto_dotl(v9ses)) |
318 | inode->i_fop = &v9fs_dir_operations_dotl; |
319 | else |
320 | inode->i_fop = &v9fs_dir_operations; |
321 | |
322 | break; |
323 | default: |
324 | p9_debug(P9_DEBUG_ERROR, "BAD mode 0x%hx S_IFMT 0x%x\n" , |
325 | mode, mode & S_IFMT); |
326 | err = -EINVAL; |
327 | goto error; |
328 | } |
329 | |
330 | v9fs_set_netfs_context(inode); |
331 | error: |
332 | return err; |
333 | |
334 | } |
335 | |
336 | /** |
337 | * v9fs_get_inode - helper function to setup an inode |
338 | * @sb: superblock |
339 | * @mode: mode to setup inode with |
340 | * @rdev: The device numbers to set |
341 | */ |
342 | |
343 | struct inode *v9fs_get_inode(struct super_block *sb, umode_t mode, dev_t rdev) |
344 | { |
345 | int err; |
346 | struct inode *inode; |
347 | struct v9fs_session_info *v9ses = sb->s_fs_info; |
348 | |
349 | p9_debug(P9_DEBUG_VFS, "super block: %p mode: %ho\n" , sb, mode); |
350 | |
351 | inode = new_inode(sb); |
352 | if (!inode) { |
353 | pr_warn("%s (%d): Problem allocating inode\n" , |
354 | __func__, task_pid_nr(current)); |
355 | return ERR_PTR(error: -ENOMEM); |
356 | } |
357 | err = v9fs_init_inode(v9ses, inode, mode, rdev); |
358 | if (err) { |
359 | iput(inode); |
360 | return ERR_PTR(error: err); |
361 | } |
362 | return inode; |
363 | } |
364 | |
365 | /** |
366 | * v9fs_evict_inode - Remove an inode from the inode cache |
367 | * @inode: inode to release |
368 | * |
369 | */ |
370 | void v9fs_evict_inode(struct inode *inode) |
371 | { |
372 | struct v9fs_inode __maybe_unused *v9inode = V9FS_I(inode); |
373 | __le32 __maybe_unused version; |
374 | |
375 | truncate_inode_pages_final(&inode->i_data); |
376 | |
377 | #ifdef CONFIG_9P_FSCACHE |
378 | version = cpu_to_le32(v9inode->qid.version); |
379 | fscache_clear_inode_writeback(cookie: v9fs_inode_cookie(v9inode), inode, |
380 | aux: &version); |
381 | #endif |
382 | |
383 | clear_inode(inode); |
384 | filemap_fdatawrite(&inode->i_data); |
385 | |
386 | #ifdef CONFIG_9P_FSCACHE |
387 | fscache_relinquish_cookie(cookie: v9fs_inode_cookie(v9inode), retire: false); |
388 | #endif |
389 | } |
390 | |
391 | static int v9fs_test_inode(struct inode *inode, void *data) |
392 | { |
393 | int umode; |
394 | dev_t rdev; |
395 | struct v9fs_inode *v9inode = V9FS_I(inode); |
396 | struct p9_wstat *st = (struct p9_wstat *)data; |
397 | struct v9fs_session_info *v9ses = v9fs_inode2v9ses(inode); |
398 | |
399 | umode = p9mode2unixmode(v9ses, stat: st, rdev: &rdev); |
400 | /* don't match inode of different type */ |
401 | if (inode_wrong_type(inode, mode: umode)) |
402 | return 0; |
403 | |
404 | /* compare qid details */ |
405 | if (memcmp(p: &v9inode->qid.version, |
406 | q: &st->qid.version, size: sizeof(v9inode->qid.version))) |
407 | return 0; |
408 | |
409 | if (v9inode->qid.type != st->qid.type) |
410 | return 0; |
411 | |
412 | if (v9inode->qid.path != st->qid.path) |
413 | return 0; |
414 | return 1; |
415 | } |
416 | |
417 | static int v9fs_test_new_inode(struct inode *inode, void *data) |
418 | { |
419 | return 0; |
420 | } |
421 | |
422 | static int v9fs_set_inode(struct inode *inode, void *data) |
423 | { |
424 | struct v9fs_inode *v9inode = V9FS_I(inode); |
425 | struct p9_wstat *st = (struct p9_wstat *)data; |
426 | |
427 | memcpy(&v9inode->qid, &st->qid, sizeof(st->qid)); |
428 | return 0; |
429 | } |
430 | |
431 | static struct inode *v9fs_qid_iget(struct super_block *sb, |
432 | struct p9_qid *qid, |
433 | struct p9_wstat *st, |
434 | int new) |
435 | { |
436 | dev_t rdev; |
437 | int retval; |
438 | umode_t umode; |
439 | unsigned long i_ino; |
440 | struct inode *inode; |
441 | struct v9fs_session_info *v9ses = sb->s_fs_info; |
442 | int (*test)(struct inode *inode, void *data); |
443 | |
444 | if (new) |
445 | test = v9fs_test_new_inode; |
446 | else |
447 | test = v9fs_test_inode; |
448 | |
449 | i_ino = v9fs_qid2ino(qid); |
450 | inode = iget5_locked(sb, i_ino, test, set: v9fs_set_inode, st); |
451 | if (!inode) |
452 | return ERR_PTR(error: -ENOMEM); |
453 | if (!(inode->i_state & I_NEW)) |
454 | return inode; |
455 | /* |
456 | * initialize the inode with the stat info |
457 | * FIXME!! we may need support for stale inodes |
458 | * later. |
459 | */ |
460 | inode->i_ino = i_ino; |
461 | umode = p9mode2unixmode(v9ses, stat: st, rdev: &rdev); |
462 | retval = v9fs_init_inode(v9ses, inode, mode: umode, rdev); |
463 | if (retval) |
464 | goto error; |
465 | |
466 | v9fs_stat2inode(stat: st, inode, sb, flags: 0); |
467 | v9fs_cache_inode_get_cookie(inode); |
468 | unlock_new_inode(inode); |
469 | return inode; |
470 | error: |
471 | iget_failed(inode); |
472 | return ERR_PTR(error: retval); |
473 | |
474 | } |
475 | |
476 | struct inode * |
477 | v9fs_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid, |
478 | struct super_block *sb, int new) |
479 | { |
480 | struct p9_wstat *st; |
481 | struct inode *inode = NULL; |
482 | |
483 | st = p9_client_stat(fid); |
484 | if (IS_ERR(ptr: st)) |
485 | return ERR_CAST(ptr: st); |
486 | |
487 | inode = v9fs_qid_iget(sb, qid: &st->qid, st, new); |
488 | p9stat_free(stbuf: st); |
489 | kfree(objp: st); |
490 | return inode; |
491 | } |
492 | |
493 | /** |
494 | * v9fs_at_to_dotl_flags- convert Linux specific AT flags to |
495 | * plan 9 AT flag. |
496 | * @flags: flags to convert |
497 | */ |
498 | static int v9fs_at_to_dotl_flags(int flags) |
499 | { |
500 | int rflags = 0; |
501 | |
502 | if (flags & AT_REMOVEDIR) |
503 | rflags |= P9_DOTL_AT_REMOVEDIR; |
504 | |
505 | return rflags; |
506 | } |
507 | |
508 | /** |
509 | * v9fs_dec_count - helper functon to drop i_nlink. |
510 | * |
511 | * If a directory had nlink <= 2 (including . and ..), then we should not drop |
512 | * the link count, which indicates the underlying exported fs doesn't maintain |
513 | * nlink accurately. e.g. |
514 | * - overlayfs sets nlink to 1 for merged dir |
515 | * - ext4 (with dir_nlink feature enabled) sets nlink to 1 if a dir has more |
516 | * than EXT4_LINK_MAX (65000) links. |
517 | * |
518 | * @inode: inode whose nlink is being dropped |
519 | */ |
520 | static void v9fs_dec_count(struct inode *inode) |
521 | { |
522 | if (!S_ISDIR(inode->i_mode) || inode->i_nlink > 2) |
523 | drop_nlink(inode); |
524 | } |
525 | |
526 | /** |
527 | * v9fs_remove - helper function to remove files and directories |
528 | * @dir: directory inode that is being deleted |
529 | * @dentry: dentry that is being deleted |
530 | * @flags: removing a directory |
531 | * |
532 | */ |
533 | |
534 | static int v9fs_remove(struct inode *dir, struct dentry *dentry, int flags) |
535 | { |
536 | struct inode *inode; |
537 | int retval = -EOPNOTSUPP; |
538 | struct p9_fid *v9fid, *dfid; |
539 | struct v9fs_session_info *v9ses; |
540 | |
541 | p9_debug(P9_DEBUG_VFS, "inode: %p dentry: %p rmdir: %x\n" , |
542 | dir, dentry, flags); |
543 | |
544 | v9ses = v9fs_inode2v9ses(inode: dir); |
545 | inode = d_inode(dentry); |
546 | dfid = v9fs_parent_fid(dentry); |
547 | if (IS_ERR(ptr: dfid)) { |
548 | retval = PTR_ERR(ptr: dfid); |
549 | p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n" , retval); |
550 | return retval; |
551 | } |
552 | if (v9fs_proto_dotl(v9ses)) |
553 | retval = p9_client_unlinkat(dfid, name: dentry->d_name.name, |
554 | flags: v9fs_at_to_dotl_flags(flags)); |
555 | p9_fid_put(fid: dfid); |
556 | if (retval == -EOPNOTSUPP) { |
557 | /* Try the one based on path */ |
558 | v9fid = v9fs_fid_clone(dentry); |
559 | if (IS_ERR(ptr: v9fid)) |
560 | return PTR_ERR(ptr: v9fid); |
561 | retval = p9_client_remove(fid: v9fid); |
562 | } |
563 | if (!retval) { |
564 | /* |
565 | * directories on unlink should have zero |
566 | * link count |
567 | */ |
568 | if (flags & AT_REMOVEDIR) { |
569 | clear_nlink(inode); |
570 | v9fs_dec_count(inode: dir); |
571 | } else |
572 | v9fs_dec_count(inode); |
573 | |
574 | v9fs_invalidate_inode_attr(inode); |
575 | v9fs_invalidate_inode_attr(inode: dir); |
576 | |
577 | /* invalidate all fids associated with dentry */ |
578 | /* NOTE: This will not include open fids */ |
579 | dentry->d_op->d_release(dentry); |
580 | } |
581 | return retval; |
582 | } |
583 | |
584 | /** |
585 | * v9fs_create - Create a file |
586 | * @v9ses: session information |
587 | * @dir: directory that dentry is being created in |
588 | * @dentry: dentry that is being created |
589 | * @extension: 9p2000.u extension string to support devices, etc. |
590 | * @perm: create permissions |
591 | * @mode: open mode |
592 | * |
593 | */ |
594 | static struct p9_fid * |
595 | v9fs_create(struct v9fs_session_info *v9ses, struct inode *dir, |
596 | struct dentry *dentry, char *extension, u32 perm, u8 mode) |
597 | { |
598 | int err; |
599 | const unsigned char *name; |
600 | struct p9_fid *dfid, *ofid = NULL, *fid = NULL; |
601 | struct inode *inode; |
602 | |
603 | p9_debug(P9_DEBUG_VFS, "name %pd\n" , dentry); |
604 | |
605 | name = dentry->d_name.name; |
606 | dfid = v9fs_parent_fid(dentry); |
607 | if (IS_ERR(ptr: dfid)) { |
608 | err = PTR_ERR(ptr: dfid); |
609 | p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n" , err); |
610 | return ERR_PTR(error: err); |
611 | } |
612 | |
613 | /* clone a fid to use for creation */ |
614 | ofid = clone_fid(fid: dfid); |
615 | if (IS_ERR(ptr: ofid)) { |
616 | err = PTR_ERR(ptr: ofid); |
617 | p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n" , err); |
618 | goto error; |
619 | } |
620 | |
621 | err = p9_client_fcreate(fid: ofid, name, perm, mode, extension); |
622 | if (err < 0) { |
623 | p9_debug(P9_DEBUG_VFS, "p9_client_fcreate failed %d\n" , err); |
624 | goto error; |
625 | } |
626 | |
627 | if (!(perm & P9_DMLINK)) { |
628 | /* now walk from the parent so we can get unopened fid */ |
629 | fid = p9_client_walk(oldfid: dfid, nwname: 1, wnames: &name, clone: 1); |
630 | if (IS_ERR(ptr: fid)) { |
631 | err = PTR_ERR(ptr: fid); |
632 | p9_debug(P9_DEBUG_VFS, |
633 | "p9_client_walk failed %d\n" , err); |
634 | goto error; |
635 | } |
636 | /* |
637 | * instantiate inode and assign the unopened fid to the dentry |
638 | */ |
639 | inode = v9fs_get_new_inode_from_fid(v9ses, fid, sb: dir->i_sb); |
640 | if (IS_ERR(ptr: inode)) { |
641 | err = PTR_ERR(ptr: inode); |
642 | p9_debug(P9_DEBUG_VFS, |
643 | "inode creation failed %d\n" , err); |
644 | goto error; |
645 | } |
646 | v9fs_fid_add(dentry, fid: &fid); |
647 | d_instantiate(dentry, inode); |
648 | } |
649 | p9_fid_put(fid: dfid); |
650 | return ofid; |
651 | error: |
652 | p9_fid_put(fid: dfid); |
653 | p9_fid_put(fid: ofid); |
654 | p9_fid_put(fid); |
655 | return ERR_PTR(error: err); |
656 | } |
657 | |
658 | /** |
659 | * v9fs_vfs_create - VFS hook to create a regular file |
660 | * @idmap: idmap of the mount |
661 | * @dir: The parent directory |
662 | * @dentry: The name of file to be created |
663 | * @mode: The UNIX file mode to set |
664 | * @excl: True if the file must not yet exist |
665 | * |
666 | * open(.., O_CREAT) is handled in v9fs_vfs_atomic_open(). This is only called |
667 | * for mknod(2). |
668 | * |
669 | */ |
670 | |
671 | static int |
672 | v9fs_vfs_create(struct mnt_idmap *idmap, struct inode *dir, |
673 | struct dentry *dentry, umode_t mode, bool excl) |
674 | { |
675 | struct v9fs_session_info *v9ses = v9fs_inode2v9ses(inode: dir); |
676 | u32 perm = unixmode2p9mode(v9ses, mode); |
677 | struct p9_fid *fid; |
678 | |
679 | /* P9_OEXCL? */ |
680 | fid = v9fs_create(v9ses, dir, dentry, NULL, perm, mode: P9_ORDWR); |
681 | if (IS_ERR(ptr: fid)) |
682 | return PTR_ERR(ptr: fid); |
683 | |
684 | v9fs_invalidate_inode_attr(inode: dir); |
685 | p9_fid_put(fid); |
686 | |
687 | return 0; |
688 | } |
689 | |
690 | /** |
691 | * v9fs_vfs_mkdir - VFS mkdir hook to create a directory |
692 | * @idmap: idmap of the mount |
693 | * @dir: inode that is being unlinked |
694 | * @dentry: dentry that is being unlinked |
695 | * @mode: mode for new directory |
696 | * |
697 | */ |
698 | |
699 | static int v9fs_vfs_mkdir(struct mnt_idmap *idmap, struct inode *dir, |
700 | struct dentry *dentry, umode_t mode) |
701 | { |
702 | int err; |
703 | u32 perm; |
704 | struct p9_fid *fid; |
705 | struct v9fs_session_info *v9ses; |
706 | |
707 | p9_debug(P9_DEBUG_VFS, "name %pd\n" , dentry); |
708 | err = 0; |
709 | v9ses = v9fs_inode2v9ses(inode: dir); |
710 | perm = unixmode2p9mode(v9ses, mode: mode | S_IFDIR); |
711 | fid = v9fs_create(v9ses, dir, dentry, NULL, perm, mode: P9_OREAD); |
712 | if (IS_ERR(ptr: fid)) { |
713 | err = PTR_ERR(ptr: fid); |
714 | fid = NULL; |
715 | } else { |
716 | inc_nlink(inode: dir); |
717 | v9fs_invalidate_inode_attr(inode: dir); |
718 | } |
719 | |
720 | if (fid) |
721 | p9_fid_put(fid); |
722 | |
723 | return err; |
724 | } |
725 | |
726 | /** |
727 | * v9fs_vfs_lookup - VFS lookup hook to "walk" to a new inode |
728 | * @dir: inode that is being walked from |
729 | * @dentry: dentry that is being walked to? |
730 | * @flags: lookup flags (unused) |
731 | * |
732 | */ |
733 | |
734 | struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry, |
735 | unsigned int flags) |
736 | { |
737 | struct dentry *res; |
738 | struct v9fs_session_info *v9ses; |
739 | struct p9_fid *dfid, *fid; |
740 | struct inode *inode; |
741 | const unsigned char *name; |
742 | |
743 | p9_debug(P9_DEBUG_VFS, "dir: %p dentry: (%pd) %p flags: %x\n" , |
744 | dir, dentry, dentry, flags); |
745 | |
746 | if (dentry->d_name.len > NAME_MAX) |
747 | return ERR_PTR(error: -ENAMETOOLONG); |
748 | |
749 | v9ses = v9fs_inode2v9ses(inode: dir); |
750 | /* We can walk d_parent because we hold the dir->i_mutex */ |
751 | dfid = v9fs_parent_fid(dentry); |
752 | if (IS_ERR(ptr: dfid)) |
753 | return ERR_CAST(ptr: dfid); |
754 | |
755 | /* |
756 | * Make sure we don't use a wrong inode due to parallel |
757 | * unlink. For cached mode create calls request for new |
758 | * inode. But with cache disabled, lookup should do this. |
759 | */ |
760 | name = dentry->d_name.name; |
761 | fid = p9_client_walk(oldfid: dfid, nwname: 1, wnames: &name, clone: 1); |
762 | p9_fid_put(fid: dfid); |
763 | if (fid == ERR_PTR(error: -ENOENT)) |
764 | inode = NULL; |
765 | else if (IS_ERR(ptr: fid)) |
766 | inode = ERR_CAST(ptr: fid); |
767 | else if (v9ses->cache & (CACHE_META|CACHE_LOOSE)) |
768 | inode = v9fs_get_inode_from_fid(v9ses, fid, sb: dir->i_sb); |
769 | else |
770 | inode = v9fs_get_new_inode_from_fid(v9ses, fid, sb: dir->i_sb); |
771 | /* |
772 | * If we had a rename on the server and a parallel lookup |
773 | * for the new name, then make sure we instantiate with |
774 | * the new name. ie look up for a/b, while on server somebody |
775 | * moved b under k and client parallely did a lookup for |
776 | * k/b. |
777 | */ |
778 | res = d_splice_alias(inode, dentry); |
779 | if (!IS_ERR(ptr: fid)) { |
780 | if (!res) |
781 | v9fs_fid_add(dentry, fid: &fid); |
782 | else if (!IS_ERR(ptr: res)) |
783 | v9fs_fid_add(dentry: res, fid: &fid); |
784 | else |
785 | p9_fid_put(fid); |
786 | } |
787 | return res; |
788 | } |
789 | |
790 | static int |
791 | v9fs_vfs_atomic_open(struct inode *dir, struct dentry *dentry, |
792 | struct file *file, unsigned int flags, umode_t mode) |
793 | { |
794 | int err; |
795 | u32 perm; |
796 | struct v9fs_inode __maybe_unused *v9inode; |
797 | struct v9fs_session_info *v9ses; |
798 | struct p9_fid *fid; |
799 | struct dentry *res = NULL; |
800 | struct inode *inode; |
801 | int p9_omode; |
802 | |
803 | if (d_in_lookup(dentry)) { |
804 | res = v9fs_vfs_lookup(dir, dentry, flags: 0); |
805 | if (IS_ERR(ptr: res)) |
806 | return PTR_ERR(ptr: res); |
807 | |
808 | if (res) |
809 | dentry = res; |
810 | } |
811 | |
812 | /* Only creates */ |
813 | if (!(flags & O_CREAT) || d_really_is_positive(dentry)) |
814 | return finish_no_open(file, dentry: res); |
815 | |
816 | v9ses = v9fs_inode2v9ses(inode: dir); |
817 | perm = unixmode2p9mode(v9ses, mode); |
818 | p9_omode = v9fs_uflags2omode(uflags: flags, extended: v9fs_proto_dotu(v9ses)); |
819 | |
820 | if ((v9ses->cache & CACHE_WRITEBACK) && (p9_omode & P9_OWRITE)) { |
821 | p9_omode = (p9_omode & ~P9_OWRITE) | P9_ORDWR; |
822 | p9_debug(P9_DEBUG_CACHE, |
823 | "write-only file with writeback enabled, creating w/ O_RDWR\n" ); |
824 | } |
825 | fid = v9fs_create(v9ses, dir, dentry, NULL, perm, mode: p9_omode); |
826 | if (IS_ERR(ptr: fid)) { |
827 | err = PTR_ERR(ptr: fid); |
828 | goto error; |
829 | } |
830 | |
831 | v9fs_invalidate_inode_attr(inode: dir); |
832 | inode = d_inode(dentry); |
833 | v9inode = V9FS_I(inode); |
834 | err = finish_open(file, dentry, open: generic_file_open); |
835 | if (err) |
836 | goto error; |
837 | |
838 | file->private_data = fid; |
839 | #ifdef CONFIG_9P_FSCACHE |
840 | if (v9ses->cache & CACHE_FSCACHE) |
841 | fscache_use_cookie(cookie: v9fs_inode_cookie(v9inode), |
842 | will_modify: file->f_mode & FMODE_WRITE); |
843 | #endif |
844 | |
845 | v9fs_fid_add_modes(fid, s_flags: v9ses->flags, s_cache: v9ses->cache, f_flags: file->f_flags); |
846 | v9fs_open_fid_add(inode, fid: &fid); |
847 | |
848 | file->f_mode |= FMODE_CREATED; |
849 | out: |
850 | dput(res); |
851 | return err; |
852 | |
853 | error: |
854 | p9_fid_put(fid); |
855 | goto out; |
856 | } |
857 | |
858 | /** |
859 | * v9fs_vfs_unlink - VFS unlink hook to delete an inode |
860 | * @i: inode that is being unlinked |
861 | * @d: dentry that is being unlinked |
862 | * |
863 | */ |
864 | |
865 | int v9fs_vfs_unlink(struct inode *i, struct dentry *d) |
866 | { |
867 | return v9fs_remove(dir: i, dentry: d, flags: 0); |
868 | } |
869 | |
870 | /** |
871 | * v9fs_vfs_rmdir - VFS unlink hook to delete a directory |
872 | * @i: inode that is being unlinked |
873 | * @d: dentry that is being unlinked |
874 | * |
875 | */ |
876 | |
877 | int v9fs_vfs_rmdir(struct inode *i, struct dentry *d) |
878 | { |
879 | return v9fs_remove(dir: i, dentry: d, AT_REMOVEDIR); |
880 | } |
881 | |
882 | /** |
883 | * v9fs_vfs_rename - VFS hook to rename an inode |
884 | * @idmap: The idmap of the mount |
885 | * @old_dir: old dir inode |
886 | * @old_dentry: old dentry |
887 | * @new_dir: new dir inode |
888 | * @new_dentry: new dentry |
889 | * @flags: RENAME_* flags |
890 | * |
891 | */ |
892 | |
893 | int |
894 | v9fs_vfs_rename(struct mnt_idmap *idmap, struct inode *old_dir, |
895 | struct dentry *old_dentry, struct inode *new_dir, |
896 | struct dentry *new_dentry, unsigned int flags) |
897 | { |
898 | int retval; |
899 | struct inode *old_inode; |
900 | struct inode *new_inode; |
901 | struct v9fs_session_info *v9ses; |
902 | struct p9_fid *oldfid = NULL, *dfid = NULL; |
903 | struct p9_fid *olddirfid = NULL; |
904 | struct p9_fid *newdirfid = NULL; |
905 | struct p9_wstat wstat; |
906 | |
907 | if (flags) |
908 | return -EINVAL; |
909 | |
910 | p9_debug(P9_DEBUG_VFS, "\n" ); |
911 | old_inode = d_inode(dentry: old_dentry); |
912 | new_inode = d_inode(dentry: new_dentry); |
913 | v9ses = v9fs_inode2v9ses(inode: old_inode); |
914 | oldfid = v9fs_fid_lookup(dentry: old_dentry); |
915 | if (IS_ERR(ptr: oldfid)) |
916 | return PTR_ERR(ptr: oldfid); |
917 | |
918 | dfid = v9fs_parent_fid(dentry: old_dentry); |
919 | olddirfid = clone_fid(fid: dfid); |
920 | p9_fid_put(fid: dfid); |
921 | dfid = NULL; |
922 | |
923 | if (IS_ERR(ptr: olddirfid)) { |
924 | retval = PTR_ERR(ptr: olddirfid); |
925 | goto error; |
926 | } |
927 | |
928 | dfid = v9fs_parent_fid(dentry: new_dentry); |
929 | newdirfid = clone_fid(fid: dfid); |
930 | p9_fid_put(fid: dfid); |
931 | dfid = NULL; |
932 | |
933 | if (IS_ERR(ptr: newdirfid)) { |
934 | retval = PTR_ERR(ptr: newdirfid); |
935 | goto error; |
936 | } |
937 | |
938 | down_write(sem: &v9ses->rename_sem); |
939 | if (v9fs_proto_dotl(v9ses)) { |
940 | retval = p9_client_renameat(olddirfid, old_name: old_dentry->d_name.name, |
941 | newdirfid, new_name: new_dentry->d_name.name); |
942 | if (retval == -EOPNOTSUPP) |
943 | retval = p9_client_rename(fid: oldfid, newdirfid, |
944 | name: new_dentry->d_name.name); |
945 | if (retval != -EOPNOTSUPP) |
946 | goto error_locked; |
947 | } |
948 | if (old_dentry->d_parent != new_dentry->d_parent) { |
949 | /* |
950 | * 9P .u can only handle file rename in the same directory |
951 | */ |
952 | |
953 | p9_debug(P9_DEBUG_ERROR, "old dir and new dir are different\n" ); |
954 | retval = -EXDEV; |
955 | goto error_locked; |
956 | } |
957 | v9fs_blank_wstat(wstat: &wstat); |
958 | wstat.muid = v9ses->uname; |
959 | wstat.name = new_dentry->d_name.name; |
960 | retval = p9_client_wstat(fid: oldfid, wst: &wstat); |
961 | |
962 | error_locked: |
963 | if (!retval) { |
964 | if (new_inode) { |
965 | if (S_ISDIR(new_inode->i_mode)) |
966 | clear_nlink(inode: new_inode); |
967 | else |
968 | v9fs_dec_count(inode: new_inode); |
969 | } |
970 | if (S_ISDIR(old_inode->i_mode)) { |
971 | if (!new_inode) |
972 | inc_nlink(inode: new_dir); |
973 | v9fs_dec_count(inode: old_dir); |
974 | } |
975 | v9fs_invalidate_inode_attr(inode: old_inode); |
976 | v9fs_invalidate_inode_attr(inode: old_dir); |
977 | v9fs_invalidate_inode_attr(inode: new_dir); |
978 | |
979 | /* successful rename */ |
980 | d_move(old_dentry, new_dentry); |
981 | } |
982 | up_write(sem: &v9ses->rename_sem); |
983 | |
984 | error: |
985 | p9_fid_put(fid: newdirfid); |
986 | p9_fid_put(fid: olddirfid); |
987 | p9_fid_put(fid: oldfid); |
988 | return retval; |
989 | } |
990 | |
991 | /** |
992 | * v9fs_vfs_getattr - retrieve file metadata |
993 | * @idmap: idmap of the mount |
994 | * @path: Object to query |
995 | * @stat: metadata structure to populate |
996 | * @request_mask: Mask of STATX_xxx flags indicating the caller's interests |
997 | * @flags: AT_STATX_xxx setting |
998 | * |
999 | */ |
1000 | |
1001 | static int |
1002 | v9fs_vfs_getattr(struct mnt_idmap *idmap, const struct path *path, |
1003 | struct kstat *stat, u32 request_mask, unsigned int flags) |
1004 | { |
1005 | struct dentry *dentry = path->dentry; |
1006 | struct inode *inode = d_inode(dentry); |
1007 | struct v9fs_session_info *v9ses; |
1008 | struct p9_fid *fid; |
1009 | struct p9_wstat *st; |
1010 | |
1011 | p9_debug(P9_DEBUG_VFS, "dentry: %p\n" , dentry); |
1012 | v9ses = v9fs_dentry2v9ses(dentry); |
1013 | if (v9ses->cache & (CACHE_META|CACHE_LOOSE)) { |
1014 | generic_fillattr(&nop_mnt_idmap, request_mask, inode, stat); |
1015 | return 0; |
1016 | } else if (v9ses->cache & CACHE_WRITEBACK) { |
1017 | if (S_ISREG(inode->i_mode)) { |
1018 | int retval = filemap_fdatawrite(inode->i_mapping); |
1019 | |
1020 | if (retval) |
1021 | p9_debug(P9_DEBUG_ERROR, |
1022 | "flushing writeback during getattr returned %d\n" , retval); |
1023 | } |
1024 | } |
1025 | fid = v9fs_fid_lookup(dentry); |
1026 | if (IS_ERR(ptr: fid)) |
1027 | return PTR_ERR(ptr: fid); |
1028 | |
1029 | st = p9_client_stat(fid); |
1030 | p9_fid_put(fid); |
1031 | if (IS_ERR(ptr: st)) |
1032 | return PTR_ERR(ptr: st); |
1033 | |
1034 | v9fs_stat2inode(stat: st, inode: d_inode(dentry), sb: dentry->d_sb, flags: 0); |
1035 | generic_fillattr(&nop_mnt_idmap, request_mask, d_inode(dentry), stat); |
1036 | |
1037 | p9stat_free(stbuf: st); |
1038 | kfree(objp: st); |
1039 | return 0; |
1040 | } |
1041 | |
1042 | /** |
1043 | * v9fs_vfs_setattr - set file metadata |
1044 | * @idmap: idmap of the mount |
1045 | * @dentry: file whose metadata to set |
1046 | * @iattr: metadata assignment structure |
1047 | * |
1048 | */ |
1049 | |
1050 | static int v9fs_vfs_setattr(struct mnt_idmap *idmap, |
1051 | struct dentry *dentry, struct iattr *iattr) |
1052 | { |
1053 | int retval, use_dentry = 0; |
1054 | struct inode *inode = d_inode(dentry); |
1055 | struct v9fs_session_info *v9ses; |
1056 | struct p9_fid *fid = NULL; |
1057 | struct p9_wstat wstat; |
1058 | |
1059 | p9_debug(P9_DEBUG_VFS, "\n" ); |
1060 | retval = setattr_prepare(&nop_mnt_idmap, dentry, iattr); |
1061 | if (retval) |
1062 | return retval; |
1063 | |
1064 | v9ses = v9fs_dentry2v9ses(dentry); |
1065 | if (iattr->ia_valid & ATTR_FILE) { |
1066 | fid = iattr->ia_file->private_data; |
1067 | WARN_ON(!fid); |
1068 | } |
1069 | if (!fid) { |
1070 | fid = v9fs_fid_lookup(dentry); |
1071 | use_dentry = 1; |
1072 | } |
1073 | if (IS_ERR(ptr: fid)) |
1074 | return PTR_ERR(ptr: fid); |
1075 | |
1076 | v9fs_blank_wstat(wstat: &wstat); |
1077 | if (iattr->ia_valid & ATTR_MODE) |
1078 | wstat.mode = unixmode2p9mode(v9ses, mode: iattr->ia_mode); |
1079 | |
1080 | if (iattr->ia_valid & ATTR_MTIME) |
1081 | wstat.mtime = iattr->ia_mtime.tv_sec; |
1082 | |
1083 | if (iattr->ia_valid & ATTR_ATIME) |
1084 | wstat.atime = iattr->ia_atime.tv_sec; |
1085 | |
1086 | if (iattr->ia_valid & ATTR_SIZE) |
1087 | wstat.length = iattr->ia_size; |
1088 | |
1089 | if (v9fs_proto_dotu(v9ses)) { |
1090 | if (iattr->ia_valid & ATTR_UID) |
1091 | wstat.n_uid = iattr->ia_uid; |
1092 | |
1093 | if (iattr->ia_valid & ATTR_GID) |
1094 | wstat.n_gid = iattr->ia_gid; |
1095 | } |
1096 | |
1097 | /* Write all dirty data */ |
1098 | if (d_is_reg(dentry)) { |
1099 | retval = filemap_fdatawrite(inode->i_mapping); |
1100 | if (retval) |
1101 | p9_debug(P9_DEBUG_ERROR, |
1102 | "flushing writeback during setattr returned %d\n" , retval); |
1103 | } |
1104 | |
1105 | retval = p9_client_wstat(fid, wst: &wstat); |
1106 | |
1107 | if (use_dentry) |
1108 | p9_fid_put(fid); |
1109 | |
1110 | if (retval < 0) |
1111 | return retval; |
1112 | |
1113 | if ((iattr->ia_valid & ATTR_SIZE) && |
1114 | iattr->ia_size != i_size_read(inode)) { |
1115 | truncate_setsize(inode, newsize: iattr->ia_size); |
1116 | truncate_pagecache(inode, new: iattr->ia_size); |
1117 | |
1118 | #ifdef CONFIG_9P_FSCACHE |
1119 | if (v9ses->cache & CACHE_FSCACHE) { |
1120 | struct v9fs_inode *v9inode = V9FS_I(inode); |
1121 | |
1122 | fscache_resize_cookie(cookie: v9fs_inode_cookie(v9inode), new_size: iattr->ia_size); |
1123 | } |
1124 | #endif |
1125 | } |
1126 | |
1127 | v9fs_invalidate_inode_attr(inode); |
1128 | |
1129 | setattr_copy(&nop_mnt_idmap, inode, attr: iattr); |
1130 | mark_inode_dirty(inode); |
1131 | return 0; |
1132 | } |
1133 | |
1134 | /** |
1135 | * v9fs_stat2inode - populate an inode structure with mistat info |
1136 | * @stat: Plan 9 metadata (mistat) structure |
1137 | * @inode: inode to populate |
1138 | * @sb: superblock of filesystem |
1139 | * @flags: control flags (e.g. V9FS_STAT2INODE_KEEP_ISIZE) |
1140 | * |
1141 | */ |
1142 | |
1143 | void |
1144 | v9fs_stat2inode(struct p9_wstat *stat, struct inode *inode, |
1145 | struct super_block *sb, unsigned int flags) |
1146 | { |
1147 | umode_t mode; |
1148 | struct v9fs_session_info *v9ses = sb->s_fs_info; |
1149 | struct v9fs_inode *v9inode = V9FS_I(inode); |
1150 | |
1151 | set_nlink(inode, nlink: 1); |
1152 | |
1153 | inode_set_atime(inode, sec: stat->atime, nsec: 0); |
1154 | inode_set_mtime(inode, sec: stat->mtime, nsec: 0); |
1155 | inode_set_ctime(inode, sec: stat->mtime, nsec: 0); |
1156 | |
1157 | inode->i_uid = v9ses->dfltuid; |
1158 | inode->i_gid = v9ses->dfltgid; |
1159 | |
1160 | if (v9fs_proto_dotu(v9ses)) { |
1161 | inode->i_uid = stat->n_uid; |
1162 | inode->i_gid = stat->n_gid; |
1163 | } |
1164 | if ((S_ISREG(inode->i_mode)) || (S_ISDIR(inode->i_mode))) { |
1165 | if (v9fs_proto_dotu(v9ses)) { |
1166 | unsigned int i_nlink; |
1167 | /* |
1168 | * Hadlink support got added later to the .u extension. |
1169 | * So there can be a server out there that doesn't |
1170 | * support this even with .u extension. That would |
1171 | * just leave us with stat->extension being an empty |
1172 | * string, though. |
1173 | */ |
1174 | /* HARDLINKCOUNT %u */ |
1175 | if (sscanf(stat->extension, |
1176 | " HARDLINKCOUNT %u" , &i_nlink) == 1) |
1177 | set_nlink(inode, nlink: i_nlink); |
1178 | } |
1179 | } |
1180 | mode = p9mode2perm(v9ses, stat); |
1181 | mode |= inode->i_mode & ~S_IALLUGO; |
1182 | inode->i_mode = mode; |
1183 | |
1184 | if (!(flags & V9FS_STAT2INODE_KEEP_ISIZE)) |
1185 | v9fs_i_size_write(inode, i_size: stat->length); |
1186 | /* not real number of blocks, but 512 byte ones ... */ |
1187 | inode->i_blocks = (stat->length + 512 - 1) >> 9; |
1188 | v9inode->cache_validity &= ~V9FS_INO_INVALID_ATTR; |
1189 | } |
1190 | |
1191 | /** |
1192 | * v9fs_qid2ino - convert qid into inode number |
1193 | * @qid: qid to hash |
1194 | * |
1195 | * BUG: potential for inode number collisions? |
1196 | */ |
1197 | |
1198 | ino_t v9fs_qid2ino(struct p9_qid *qid) |
1199 | { |
1200 | u64 path = qid->path + 2; |
1201 | ino_t i = 0; |
1202 | |
1203 | if (sizeof(ino_t) == sizeof(path)) |
1204 | memcpy(&i, &path, sizeof(ino_t)); |
1205 | else |
1206 | i = (ino_t) (path ^ (path >> 32)); |
1207 | |
1208 | return i; |
1209 | } |
1210 | |
1211 | /** |
1212 | * v9fs_vfs_get_link - follow a symlink path |
1213 | * @dentry: dentry for symlink |
1214 | * @inode: inode for symlink |
1215 | * @done: delayed call for when we are done with the return value |
1216 | */ |
1217 | |
1218 | static const char *v9fs_vfs_get_link(struct dentry *dentry, |
1219 | struct inode *inode, |
1220 | struct delayed_call *done) |
1221 | { |
1222 | struct v9fs_session_info *v9ses; |
1223 | struct p9_fid *fid; |
1224 | struct p9_wstat *st; |
1225 | char *res; |
1226 | |
1227 | if (!dentry) |
1228 | return ERR_PTR(error: -ECHILD); |
1229 | |
1230 | v9ses = v9fs_dentry2v9ses(dentry); |
1231 | if (!v9fs_proto_dotu(v9ses)) |
1232 | return ERR_PTR(error: -EBADF); |
1233 | |
1234 | p9_debug(P9_DEBUG_VFS, "%pd\n" , dentry); |
1235 | fid = v9fs_fid_lookup(dentry); |
1236 | |
1237 | if (IS_ERR(ptr: fid)) |
1238 | return ERR_CAST(ptr: fid); |
1239 | |
1240 | st = p9_client_stat(fid); |
1241 | p9_fid_put(fid); |
1242 | if (IS_ERR(ptr: st)) |
1243 | return ERR_CAST(ptr: st); |
1244 | |
1245 | if (!(st->mode & P9_DMSYMLINK)) { |
1246 | p9stat_free(stbuf: st); |
1247 | kfree(objp: st); |
1248 | return ERR_PTR(error: -EINVAL); |
1249 | } |
1250 | res = st->extension; |
1251 | st->extension = NULL; |
1252 | if (strlen(res) >= PATH_MAX) |
1253 | res[PATH_MAX - 1] = '\0'; |
1254 | |
1255 | p9stat_free(stbuf: st); |
1256 | kfree(objp: st); |
1257 | set_delayed_call(call: done, fn: kfree_link, arg: res); |
1258 | return res; |
1259 | } |
1260 | |
1261 | /** |
1262 | * v9fs_vfs_mkspecial - create a special file |
1263 | * @dir: inode to create special file in |
1264 | * @dentry: dentry to create |
1265 | * @perm: mode to create special file |
1266 | * @extension: 9p2000.u format extension string representing special file |
1267 | * |
1268 | */ |
1269 | |
1270 | static int v9fs_vfs_mkspecial(struct inode *dir, struct dentry *dentry, |
1271 | u32 perm, const char *extension) |
1272 | { |
1273 | struct p9_fid *fid; |
1274 | struct v9fs_session_info *v9ses; |
1275 | |
1276 | v9ses = v9fs_inode2v9ses(inode: dir); |
1277 | if (!v9fs_proto_dotu(v9ses)) { |
1278 | p9_debug(P9_DEBUG_ERROR, "not extended\n" ); |
1279 | return -EPERM; |
1280 | } |
1281 | |
1282 | fid = v9fs_create(v9ses, dir, dentry, extension: (char *) extension, perm, |
1283 | mode: P9_OREAD); |
1284 | if (IS_ERR(ptr: fid)) |
1285 | return PTR_ERR(ptr: fid); |
1286 | |
1287 | v9fs_invalidate_inode_attr(inode: dir); |
1288 | p9_fid_put(fid); |
1289 | return 0; |
1290 | } |
1291 | |
1292 | /** |
1293 | * v9fs_vfs_symlink - helper function to create symlinks |
1294 | * @idmap: idmap of the mount |
1295 | * @dir: directory inode containing symlink |
1296 | * @dentry: dentry for symlink |
1297 | * @symname: symlink data |
1298 | * |
1299 | * See Also: 9P2000.u RFC for more information |
1300 | * |
1301 | */ |
1302 | |
1303 | static int |
1304 | v9fs_vfs_symlink(struct mnt_idmap *idmap, struct inode *dir, |
1305 | struct dentry *dentry, const char *symname) |
1306 | { |
1307 | p9_debug(P9_DEBUG_VFS, " %lu,%pd,%s\n" , |
1308 | dir->i_ino, dentry, symname); |
1309 | |
1310 | return v9fs_vfs_mkspecial(dir, dentry, perm: P9_DMSYMLINK, extension: symname); |
1311 | } |
1312 | |
1313 | #define U32_MAX_DIGITS 10 |
1314 | |
1315 | /** |
1316 | * v9fs_vfs_link - create a hardlink |
1317 | * @old_dentry: dentry for file to link to |
1318 | * @dir: inode destination for new link |
1319 | * @dentry: dentry for link |
1320 | * |
1321 | */ |
1322 | |
1323 | static int |
1324 | v9fs_vfs_link(struct dentry *old_dentry, struct inode *dir, |
1325 | struct dentry *dentry) |
1326 | { |
1327 | int retval; |
1328 | char name[1 + U32_MAX_DIGITS + 2]; /* sign + number + \n + \0 */ |
1329 | struct p9_fid *oldfid; |
1330 | |
1331 | p9_debug(P9_DEBUG_VFS, " %lu,%pd,%pd\n" , |
1332 | dir->i_ino, dentry, old_dentry); |
1333 | |
1334 | oldfid = v9fs_fid_clone(dentry: old_dentry); |
1335 | if (IS_ERR(ptr: oldfid)) |
1336 | return PTR_ERR(ptr: oldfid); |
1337 | |
1338 | sprintf(buf: name, fmt: "%d\n" , oldfid->fid); |
1339 | retval = v9fs_vfs_mkspecial(dir, dentry, perm: P9_DMLINK, extension: name); |
1340 | if (!retval) { |
1341 | v9fs_refresh_inode(fid: oldfid, inode: d_inode(dentry: old_dentry)); |
1342 | v9fs_invalidate_inode_attr(inode: dir); |
1343 | } |
1344 | p9_fid_put(fid: oldfid); |
1345 | return retval; |
1346 | } |
1347 | |
1348 | /** |
1349 | * v9fs_vfs_mknod - create a special file |
1350 | * @idmap: idmap of the mount |
1351 | * @dir: inode destination for new link |
1352 | * @dentry: dentry for file |
1353 | * @mode: mode for creation |
1354 | * @rdev: device associated with special file |
1355 | * |
1356 | */ |
1357 | |
1358 | static int |
1359 | v9fs_vfs_mknod(struct mnt_idmap *idmap, struct inode *dir, |
1360 | struct dentry *dentry, umode_t mode, dev_t rdev) |
1361 | { |
1362 | struct v9fs_session_info *v9ses = v9fs_inode2v9ses(inode: dir); |
1363 | int retval; |
1364 | char name[2 + U32_MAX_DIGITS + 1 + U32_MAX_DIGITS + 1]; |
1365 | u32 perm; |
1366 | |
1367 | p9_debug(P9_DEBUG_VFS, " %lu,%pd mode: %x MAJOR: %u MINOR: %u\n" , |
1368 | dir->i_ino, dentry, mode, |
1369 | MAJOR(rdev), MINOR(rdev)); |
1370 | |
1371 | /* build extension */ |
1372 | if (S_ISBLK(mode)) |
1373 | sprintf(buf: name, fmt: "b %u %u" , MAJOR(rdev), MINOR(rdev)); |
1374 | else if (S_ISCHR(mode)) |
1375 | sprintf(buf: name, fmt: "c %u %u" , MAJOR(rdev), MINOR(rdev)); |
1376 | else |
1377 | *name = 0; |
1378 | |
1379 | perm = unixmode2p9mode(v9ses, mode); |
1380 | retval = v9fs_vfs_mkspecial(dir, dentry, perm, extension: name); |
1381 | |
1382 | return retval; |
1383 | } |
1384 | |
1385 | int v9fs_refresh_inode(struct p9_fid *fid, struct inode *inode) |
1386 | { |
1387 | int umode; |
1388 | dev_t rdev; |
1389 | struct p9_wstat *st; |
1390 | struct v9fs_session_info *v9ses; |
1391 | unsigned int flags; |
1392 | |
1393 | v9ses = v9fs_inode2v9ses(inode); |
1394 | st = p9_client_stat(fid); |
1395 | if (IS_ERR(ptr: st)) |
1396 | return PTR_ERR(ptr: st); |
1397 | /* |
1398 | * Don't update inode if the file type is different |
1399 | */ |
1400 | umode = p9mode2unixmode(v9ses, stat: st, rdev: &rdev); |
1401 | if (inode_wrong_type(inode, mode: umode)) |
1402 | goto out; |
1403 | |
1404 | /* |
1405 | * We don't want to refresh inode->i_size, |
1406 | * because we may have cached data |
1407 | */ |
1408 | flags = (v9ses->cache & CACHE_LOOSE) ? |
1409 | V9FS_STAT2INODE_KEEP_ISIZE : 0; |
1410 | v9fs_stat2inode(stat: st, inode, sb: inode->i_sb, flags); |
1411 | out: |
1412 | p9stat_free(stbuf: st); |
1413 | kfree(objp: st); |
1414 | return 0; |
1415 | } |
1416 | |
1417 | static const struct inode_operations v9fs_dir_inode_operations_dotu = { |
1418 | .create = v9fs_vfs_create, |
1419 | .lookup = v9fs_vfs_lookup, |
1420 | .atomic_open = v9fs_vfs_atomic_open, |
1421 | .symlink = v9fs_vfs_symlink, |
1422 | .link = v9fs_vfs_link, |
1423 | .unlink = v9fs_vfs_unlink, |
1424 | .mkdir = v9fs_vfs_mkdir, |
1425 | .rmdir = v9fs_vfs_rmdir, |
1426 | .mknod = v9fs_vfs_mknod, |
1427 | .rename = v9fs_vfs_rename, |
1428 | .getattr = v9fs_vfs_getattr, |
1429 | .setattr = v9fs_vfs_setattr, |
1430 | }; |
1431 | |
1432 | static const struct inode_operations v9fs_dir_inode_operations = { |
1433 | .create = v9fs_vfs_create, |
1434 | .lookup = v9fs_vfs_lookup, |
1435 | .atomic_open = v9fs_vfs_atomic_open, |
1436 | .unlink = v9fs_vfs_unlink, |
1437 | .mkdir = v9fs_vfs_mkdir, |
1438 | .rmdir = v9fs_vfs_rmdir, |
1439 | .mknod = v9fs_vfs_mknod, |
1440 | .rename = v9fs_vfs_rename, |
1441 | .getattr = v9fs_vfs_getattr, |
1442 | .setattr = v9fs_vfs_setattr, |
1443 | }; |
1444 | |
1445 | static const struct inode_operations v9fs_file_inode_operations = { |
1446 | .getattr = v9fs_vfs_getattr, |
1447 | .setattr = v9fs_vfs_setattr, |
1448 | }; |
1449 | |
1450 | static const struct inode_operations v9fs_symlink_inode_operations = { |
1451 | .get_link = v9fs_vfs_get_link, |
1452 | .getattr = v9fs_vfs_getattr, |
1453 | .setattr = v9fs_vfs_setattr, |
1454 | }; |
1455 | |
1456 | |