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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/inet.h>
19#include <linux/namei.h>
20#include <linux/sched.h>
21#include <linux/slab.h>
22#include <linux/xattr.h>
23#include <linux/posix_acl.h>
24#include <net/9p/9p.h>
25#include <net/9p/client.h>
26
27#include "v9fs.h"
28#include "v9fs_vfs.h"
29#include "fid.h"
30#include "cache.h"
31#include "xattr.h"
32#include "acl.h"
33
34static const struct inode_operations v9fs_dir_inode_operations;
35static const struct inode_operations v9fs_dir_inode_operations_dotu;
36static const struct inode_operations v9fs_file_inode_operations;
37static const struct inode_operations v9fs_symlink_inode_operations;
38
39/**
40 * unixmode2p9mode - convert unix mode bits to plan 9
41 * @v9ses: v9fs session information
42 * @mode: mode to convert
43 *
44 */
45
46static u32 unixmode2p9mode(struct v9fs_session_info *v9ses, umode_t mode)
47{
48 int res;
49
50 res = mode & 0777;
51 if (S_ISDIR(mode))
52 res |= P9_DMDIR;
53 if (v9fs_proto_dotu(v9ses)) {
54 if (v9ses->nodev == 0) {
55 if (S_ISSOCK(mode))
56 res |= P9_DMSOCKET;
57 if (S_ISFIFO(mode))
58 res |= P9_DMNAMEDPIPE;
59 if (S_ISBLK(mode))
60 res |= P9_DMDEVICE;
61 if (S_ISCHR(mode))
62 res |= P9_DMDEVICE;
63 }
64
65 if ((mode & S_ISUID) == S_ISUID)
66 res |= P9_DMSETUID;
67 if ((mode & S_ISGID) == S_ISGID)
68 res |= P9_DMSETGID;
69 if ((mode & S_ISVTX) == S_ISVTX)
70 res |= P9_DMSETVTX;
71 }
72 return res;
73}
74
75/**
76 * p9mode2perm- convert plan9 mode bits to unix permission bits
77 * @v9ses: v9fs session information
78 * @stat: p9_wstat from which mode need to be derived
79 *
80 */
81static int p9mode2perm(struct v9fs_session_info *v9ses,
82 struct p9_wstat *stat)
83{
84 int res;
85 int mode = stat->mode;
86
87 res = mode & S_IALLUGO;
88 if (v9fs_proto_dotu(v9ses)) {
89 if ((mode & P9_DMSETUID) == P9_DMSETUID)
90 res |= S_ISUID;
91
92 if ((mode & P9_DMSETGID) == P9_DMSETGID)
93 res |= S_ISGID;
94
95 if ((mode & P9_DMSETVTX) == P9_DMSETVTX)
96 res |= S_ISVTX;
97 }
98 return res;
99}
100
101/**
102 * p9mode2unixmode- convert plan9 mode bits to unix mode bits
103 * @v9ses: v9fs session information
104 * @stat: p9_wstat from which mode need to be derived
105 * @rdev: major number, minor number in case of device files.
106 *
107 */
108static umode_t p9mode2unixmode(struct v9fs_session_info *v9ses,
109 struct p9_wstat *stat, dev_t *rdev)
110{
111 int res, r;
112 u32 mode = stat->mode;
113
114 *rdev = 0;
115 res = p9mode2perm(v9ses, stat);
116
117 if ((mode & P9_DMDIR) == P9_DMDIR)
118 res |= S_IFDIR;
119 else if ((mode & P9_DMSYMLINK) && (v9fs_proto_dotu(v9ses)))
120 res |= S_IFLNK;
121 else if ((mode & P9_DMSOCKET) && (v9fs_proto_dotu(v9ses))
122 && (v9ses->nodev == 0))
123 res |= S_IFSOCK;
124 else if ((mode & P9_DMNAMEDPIPE) && (v9fs_proto_dotu(v9ses))
125 && (v9ses->nodev == 0))
126 res |= S_IFIFO;
127 else if ((mode & P9_DMDEVICE) && (v9fs_proto_dotu(v9ses))
128 && (v9ses->nodev == 0)) {
129 char type = 0;
130 int major = -1, minor = -1;
131
132 r = sscanf(stat->extension, "%c %i %i", &type, &major, &minor);
133 if (r != 3) {
134 p9_debug(P9_DEBUG_ERROR,
135 "invalid device string, umode will be bogus: %s\n",
136 stat->extension);
137 return res;
138 }
139 switch (type) {
140 case 'c':
141 res |= S_IFCHR;
142 break;
143 case 'b':
144 res |= S_IFBLK;
145 break;
146 default:
147 p9_debug(P9_DEBUG_ERROR, "Unknown special type %c %s\n",
148 type, stat->extension);
149 }
150 *rdev = MKDEV(major, minor);
151 } else
152 res |= S_IFREG;
153
154 return res;
155}
156
157/**
158 * v9fs_uflags2omode- convert posix open flags to plan 9 mode bits
159 * @uflags: flags to convert
160 * @extended: if .u extensions are active
161 */
162
163int v9fs_uflags2omode(int uflags, int extended)
164{
165 int ret;
166
167 ret = 0;
168 switch (uflags&3) {
169 default:
170 case O_RDONLY:
171 ret = P9_OREAD;
172 break;
173
174 case O_WRONLY:
175 ret = P9_OWRITE;
176 break;
177
178 case O_RDWR:
179 ret = P9_ORDWR;
180 break;
181 }
182
183 if (extended) {
184 if (uflags & O_EXCL)
185 ret |= P9_OEXCL;
186
187 if (uflags & O_APPEND)
188 ret |= P9_OAPPEND;
189 }
190
191 return ret;
192}
193
194/**
195 * v9fs_blank_wstat - helper function to setup a 9P stat structure
196 * @wstat: structure to initialize
197 *
198 */
199
200void
201v9fs_blank_wstat(struct p9_wstat *wstat)
202{
203 wstat->type = ~0;
204 wstat->dev = ~0;
205 wstat->qid.type = ~0;
206 wstat->qid.version = ~0;
207 *((long long *)&wstat->qid.path) = ~0;
208 wstat->mode = ~0;
209 wstat->atime = ~0;
210 wstat->mtime = ~0;
211 wstat->length = ~0;
212 wstat->name = NULL;
213 wstat->uid = NULL;
214 wstat->gid = NULL;
215 wstat->muid = NULL;
216 wstat->n_uid = INVALID_UID;
217 wstat->n_gid = INVALID_GID;
218 wstat->n_muid = INVALID_UID;
219 wstat->extension = NULL;
220}
221
222/**
223 * v9fs_alloc_inode - helper function to allocate an inode
224 * @sb: The superblock to allocate the inode from
225 */
226struct inode *v9fs_alloc_inode(struct super_block *sb)
227{
228 struct v9fs_inode *v9inode;
229
230 v9inode = alloc_inode_sb(sb, v9fs_inode_cache, GFP_KERNEL);
231 if (!v9inode)
232 return NULL;
233 v9inode->writeback_fid = NULL;
234 v9inode->cache_validity = 0;
235 mutex_init(&v9inode->v_mutex);
236 return &v9inode->netfs.inode;
237}
238
239/**
240 * v9fs_free_inode - destroy an inode
241 * @inode: The inode to be freed
242 */
243
244void v9fs_free_inode(struct inode *inode)
245{
246 kmem_cache_free(v9fs_inode_cache, V9FS_I(inode));
247}
248
249/*
250 * Set parameters for the netfs library
251 */
252static void v9fs_set_netfs_context(struct inode *inode)
253{
254 struct v9fs_inode *v9inode = V9FS_I(inode);
255 netfs_inode_init(&v9inode->netfs, &v9fs_req_ops);
256}
257
258int v9fs_init_inode(struct v9fs_session_info *v9ses,
259 struct inode *inode, umode_t mode, dev_t rdev)
260{
261 int err = 0;
262
263 inode_init_owner(&init_user_ns, inode, NULL, mode);
264 inode->i_blocks = 0;
265 inode->i_rdev = rdev;
266 inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
267 inode->i_mapping->a_ops = &v9fs_addr_operations;
268 inode->i_private = NULL;
269
270 switch (mode & S_IFMT) {
271 case S_IFIFO:
272 case S_IFBLK:
273 case S_IFCHR:
274 case S_IFSOCK:
275 if (v9fs_proto_dotl(v9ses)) {
276 inode->i_op = &v9fs_file_inode_operations_dotl;
277 } else if (v9fs_proto_dotu(v9ses)) {
278 inode->i_op = &v9fs_file_inode_operations;
279 } else {
280 p9_debug(P9_DEBUG_ERROR,
281 "special files without extended mode\n");
282 err = -EINVAL;
283 goto error;
284 }
285 init_special_inode(inode, inode->i_mode, inode->i_rdev);
286 break;
287 case S_IFREG:
288 if (v9fs_proto_dotl(v9ses)) {
289 inode->i_op = &v9fs_file_inode_operations_dotl;
290 if (v9ses->cache == CACHE_LOOSE ||
291 v9ses->cache == CACHE_FSCACHE)
292 inode->i_fop =
293 &v9fs_cached_file_operations_dotl;
294 else if (v9ses->cache == CACHE_MMAP)
295 inode->i_fop = &v9fs_mmap_file_operations_dotl;
296 else
297 inode->i_fop = &v9fs_file_operations_dotl;
298 } else {
299 inode->i_op = &v9fs_file_inode_operations;
300 if (v9ses->cache == CACHE_LOOSE ||
301 v9ses->cache == CACHE_FSCACHE)
302 inode->i_fop =
303 &v9fs_cached_file_operations;
304 else if (v9ses->cache == CACHE_MMAP)
305 inode->i_fop = &v9fs_mmap_file_operations;
306 else
307 inode->i_fop = &v9fs_file_operations;
308 }
309
310 break;
311 case S_IFLNK:
312 if (!v9fs_proto_dotu(v9ses) && !v9fs_proto_dotl(v9ses)) {
313 p9_debug(P9_DEBUG_ERROR,
314 "extended modes used with legacy protocol\n");
315 err = -EINVAL;
316 goto error;
317 }
318
319 if (v9fs_proto_dotl(v9ses))
320 inode->i_op = &v9fs_symlink_inode_operations_dotl;
321 else
322 inode->i_op = &v9fs_symlink_inode_operations;
323
324 break;
325 case S_IFDIR:
326 inc_nlink(inode);
327 if (v9fs_proto_dotl(v9ses))
328 inode->i_op = &v9fs_dir_inode_operations_dotl;
329 else if (v9fs_proto_dotu(v9ses))
330 inode->i_op = &v9fs_dir_inode_operations_dotu;
331 else
332 inode->i_op = &v9fs_dir_inode_operations;
333
334 if (v9fs_proto_dotl(v9ses))
335 inode->i_fop = &v9fs_dir_operations_dotl;
336 else
337 inode->i_fop = &v9fs_dir_operations;
338
339 break;
340 default:
341 p9_debug(P9_DEBUG_ERROR, "BAD mode 0x%hx S_IFMT 0x%x\n",
342 mode, mode & S_IFMT);
343 err = -EINVAL;
344 goto error;
345 }
346
347 v9fs_set_netfs_context(inode);
348error:
349 return err;
350
351}
352
353/**
354 * v9fs_get_inode - helper function to setup an inode
355 * @sb: superblock
356 * @mode: mode to setup inode with
357 * @rdev: The device numbers to set
358 */
359
360struct inode *v9fs_get_inode(struct super_block *sb, umode_t mode, dev_t rdev)
361{
362 int err;
363 struct inode *inode;
364 struct v9fs_session_info *v9ses = sb->s_fs_info;
365
366 p9_debug(P9_DEBUG_VFS, "super block: %p mode: %ho\n", sb, mode);
367
368 inode = new_inode(sb);
369 if (!inode) {
370 pr_warn("%s (%d): Problem allocating inode\n",
371 __func__, task_pid_nr(current));
372 return ERR_PTR(-ENOMEM);
373 }
374 err = v9fs_init_inode(v9ses, inode, mode, rdev);
375 if (err) {
376 iput(inode);
377 return ERR_PTR(err);
378 }
379 return inode;
380}
381
382/**
383 * v9fs_evict_inode - Remove an inode from the inode cache
384 * @inode: inode to release
385 *
386 */
387void v9fs_evict_inode(struct inode *inode)
388{
389 struct v9fs_inode *v9inode = V9FS_I(inode);
390 __le32 version;
391
392 truncate_inode_pages_final(&inode->i_data);
393 version = cpu_to_le32(v9inode->qid.version);
394 fscache_clear_inode_writeback(v9fs_inode_cookie(v9inode), inode,
395 &version);
396 clear_inode(inode);
397 filemap_fdatawrite(&inode->i_data);
398
399 fscache_relinquish_cookie(v9fs_inode_cookie(v9inode), false);
400 /* clunk the fid stashed in writeback_fid */
401 p9_fid_put(v9inode->writeback_fid);
402 v9inode->writeback_fid = NULL;
403}
404
405static int v9fs_test_inode(struct inode *inode, void *data)
406{
407 int umode;
408 dev_t rdev;
409 struct v9fs_inode *v9inode = V9FS_I(inode);
410 struct p9_wstat *st = (struct p9_wstat *)data;
411 struct v9fs_session_info *v9ses = v9fs_inode2v9ses(inode);
412
413 umode = p9mode2unixmode(v9ses, st, &rdev);
414 /* don't match inode of different type */
415 if (inode_wrong_type(inode, umode))
416 return 0;
417
418 /* compare qid details */
419 if (memcmp(&v9inode->qid.version,
420 &st->qid.version, sizeof(v9inode->qid.version)))
421 return 0;
422
423 if (v9inode->qid.type != st->qid.type)
424 return 0;
425
426 if (v9inode->qid.path != st->qid.path)
427 return 0;
428 return 1;
429}
430
431static int v9fs_test_new_inode(struct inode *inode, void *data)
432{
433 return 0;
434}
435
436static int v9fs_set_inode(struct inode *inode, void *data)
437{
438 struct v9fs_inode *v9inode = V9FS_I(inode);
439 struct p9_wstat *st = (struct p9_wstat *)data;
440
441 memcpy(&v9inode->qid, &st->qid, sizeof(st->qid));
442 return 0;
443}
444
445static struct inode *v9fs_qid_iget(struct super_block *sb,
446 struct p9_qid *qid,
447 struct p9_wstat *st,
448 int new)
449{
450 dev_t rdev;
451 int retval;
452 umode_t umode;
453 unsigned long i_ino;
454 struct inode *inode;
455 struct v9fs_session_info *v9ses = sb->s_fs_info;
456 int (*test)(struct inode *inode, void *data);
457
458 if (new)
459 test = v9fs_test_new_inode;
460 else
461 test = v9fs_test_inode;
462
463 i_ino = v9fs_qid2ino(qid);
464 inode = iget5_locked(sb, i_ino, test, v9fs_set_inode, st);
465 if (!inode)
466 return ERR_PTR(-ENOMEM);
467 if (!(inode->i_state & I_NEW))
468 return inode;
469 /*
470 * initialize the inode with the stat info
471 * FIXME!! we may need support for stale inodes
472 * later.
473 */
474 inode->i_ino = i_ino;
475 umode = p9mode2unixmode(v9ses, st, &rdev);
476 retval = v9fs_init_inode(v9ses, inode, umode, rdev);
477 if (retval)
478 goto error;
479
480 v9fs_stat2inode(st, inode, sb, 0);
481 v9fs_cache_inode_get_cookie(inode);
482 unlock_new_inode(inode);
483 return inode;
484error:
485 iget_failed(inode);
486 return ERR_PTR(retval);
487
488}
489
490struct inode *
491v9fs_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid,
492 struct super_block *sb, int new)
493{
494 struct p9_wstat *st;
495 struct inode *inode = NULL;
496
497 st = p9_client_stat(fid);
498 if (IS_ERR(st))
499 return ERR_CAST(st);
500
501 inode = v9fs_qid_iget(sb, &st->qid, st, new);
502 p9stat_free(st);
503 kfree(st);
504 return inode;
505}
506
507/**
508 * v9fs_at_to_dotl_flags- convert Linux specific AT flags to
509 * plan 9 AT flag.
510 * @flags: flags to convert
511 */
512static int v9fs_at_to_dotl_flags(int flags)
513{
514 int rflags = 0;
515
516 if (flags & AT_REMOVEDIR)
517 rflags |= P9_DOTL_AT_REMOVEDIR;
518
519 return rflags;
520}
521
522/**
523 * v9fs_dec_count - helper functon to drop i_nlink.
524 *
525 * If a directory had nlink <= 2 (including . and ..), then we should not drop
526 * the link count, which indicates the underlying exported fs doesn't maintain
527 * nlink accurately. e.g.
528 * - overlayfs sets nlink to 1 for merged dir
529 * - ext4 (with dir_nlink feature enabled) sets nlink to 1 if a dir has more
530 * than EXT4_LINK_MAX (65000) links.
531 *
532 * @inode: inode whose nlink is being dropped
533 */
534static void v9fs_dec_count(struct inode *inode)
535{
536 if (!S_ISDIR(inode->i_mode) || inode->i_nlink > 2)
537 drop_nlink(inode);
538}
539
540/**
541 * v9fs_remove - helper function to remove files and directories
542 * @dir: directory inode that is being deleted
543 * @dentry: dentry that is being deleted
544 * @flags: removing a directory
545 *
546 */
547
548static int v9fs_remove(struct inode *dir, struct dentry *dentry, int flags)
549{
550 struct inode *inode;
551 int retval = -EOPNOTSUPP;
552 struct p9_fid *v9fid, *dfid;
553 struct v9fs_session_info *v9ses;
554
555 p9_debug(P9_DEBUG_VFS, "inode: %p dentry: %p rmdir: %x\n",
556 dir, dentry, flags);
557
558 v9ses = v9fs_inode2v9ses(dir);
559 inode = d_inode(dentry);
560 dfid = v9fs_parent_fid(dentry);
561 if (IS_ERR(dfid)) {
562 retval = PTR_ERR(dfid);
563 p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", retval);
564 return retval;
565 }
566 if (v9fs_proto_dotl(v9ses))
567 retval = p9_client_unlinkat(dfid, dentry->d_name.name,
568 v9fs_at_to_dotl_flags(flags));
569 p9_fid_put(dfid);
570 if (retval == -EOPNOTSUPP) {
571 /* Try the one based on path */
572 v9fid = v9fs_fid_clone(dentry);
573 if (IS_ERR(v9fid))
574 return PTR_ERR(v9fid);
575 retval = p9_client_remove(v9fid);
576 }
577 if (!retval) {
578 /*
579 * directories on unlink should have zero
580 * link count
581 */
582 if (flags & AT_REMOVEDIR) {
583 clear_nlink(inode);
584 v9fs_dec_count(dir);
585 } else
586 v9fs_dec_count(inode);
587
588 v9fs_invalidate_inode_attr(inode);
589 v9fs_invalidate_inode_attr(dir);
590
591 /* invalidate all fids associated with dentry */
592 /* NOTE: This will not include open fids */
593 dentry->d_op->d_release(dentry);
594 }
595 return retval;
596}
597
598/**
599 * v9fs_create - Create a file
600 * @v9ses: session information
601 * @dir: directory that dentry is being created in
602 * @dentry: dentry that is being created
603 * @extension: 9p2000.u extension string to support devices, etc.
604 * @perm: create permissions
605 * @mode: open mode
606 *
607 */
608static struct p9_fid *
609v9fs_create(struct v9fs_session_info *v9ses, struct inode *dir,
610 struct dentry *dentry, char *extension, u32 perm, u8 mode)
611{
612 int err;
613 const unsigned char *name;
614 struct p9_fid *dfid, *ofid = NULL, *fid = NULL;
615 struct inode *inode;
616
617 p9_debug(P9_DEBUG_VFS, "name %pd\n", dentry);
618
619 err = 0;
620 name = dentry->d_name.name;
621 dfid = v9fs_parent_fid(dentry);
622 if (IS_ERR(dfid)) {
623 err = PTR_ERR(dfid);
624 p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
625 return ERR_PTR(err);
626 }
627
628 /* clone a fid to use for creation */
629 ofid = clone_fid(dfid);
630 if (IS_ERR(ofid)) {
631 err = PTR_ERR(ofid);
632 p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
633 goto error;
634 }
635
636 err = p9_client_fcreate(ofid, name, perm, mode, extension);
637 if (err < 0) {
638 p9_debug(P9_DEBUG_VFS, "p9_client_fcreate failed %d\n", err);
639 goto error;
640 }
641
642 if (!(perm & P9_DMLINK)) {
643 /* now walk from the parent so we can get unopened fid */
644 fid = p9_client_walk(dfid, 1, &name, 1);
645 if (IS_ERR(fid)) {
646 err = PTR_ERR(fid);
647 p9_debug(P9_DEBUG_VFS,
648 "p9_client_walk failed %d\n", err);
649 goto error;
650 }
651 /*
652 * instantiate inode and assign the unopened fid to the dentry
653 */
654 inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
655 if (IS_ERR(inode)) {
656 err = PTR_ERR(inode);
657 p9_debug(P9_DEBUG_VFS,
658 "inode creation failed %d\n", err);
659 goto error;
660 }
661 v9fs_fid_add(dentry, &fid);
662 d_instantiate(dentry, inode);
663 }
664 p9_fid_put(dfid);
665 return ofid;
666error:
667 p9_fid_put(dfid);
668 p9_fid_put(ofid);
669 p9_fid_put(fid);
670 return ERR_PTR(err);
671}
672
673/**
674 * v9fs_vfs_create - VFS hook to create a regular file
675 * @mnt_userns: The user namespace of the mount
676 * @dir: The parent directory
677 * @dentry: The name of file to be created
678 * @mode: The UNIX file mode to set
679 * @excl: True if the file must not yet exist
680 *
681 * open(.., O_CREAT) is handled in v9fs_vfs_atomic_open(). This is only called
682 * for mknod(2).
683 *
684 */
685
686static int
687v9fs_vfs_create(struct user_namespace *mnt_userns, struct inode *dir,
688 struct dentry *dentry, umode_t mode, bool excl)
689{
690 struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dir);
691 u32 perm = unixmode2p9mode(v9ses, mode);
692 struct p9_fid *fid;
693
694 /* P9_OEXCL? */
695 fid = v9fs_create(v9ses, dir, dentry, NULL, perm, P9_ORDWR);
696 if (IS_ERR(fid))
697 return PTR_ERR(fid);
698
699 v9fs_invalidate_inode_attr(dir);
700 p9_fid_put(fid);
701
702 return 0;
703}
704
705/**
706 * v9fs_vfs_mkdir - VFS mkdir hook to create a directory
707 * @mnt_userns: The user namespace of the mount
708 * @dir: inode that is being unlinked
709 * @dentry: dentry that is being unlinked
710 * @mode: mode for new directory
711 *
712 */
713
714static int v9fs_vfs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
715 struct dentry *dentry, umode_t mode)
716{
717 int err;
718 u32 perm;
719 struct p9_fid *fid;
720 struct v9fs_session_info *v9ses;
721
722 p9_debug(P9_DEBUG_VFS, "name %pd\n", dentry);
723 err = 0;
724 v9ses = v9fs_inode2v9ses(dir);
725 perm = unixmode2p9mode(v9ses, mode | S_IFDIR);
726 fid = v9fs_create(v9ses, dir, dentry, NULL, perm, P9_OREAD);
727 if (IS_ERR(fid)) {
728 err = PTR_ERR(fid);
729 fid = NULL;
730 } else {
731 inc_nlink(dir);
732 v9fs_invalidate_inode_attr(dir);
733 }
734
735 if (fid)
736 p9_fid_put(fid);
737
738 return err;
739}
740
741/**
742 * v9fs_vfs_lookup - VFS lookup hook to "walk" to a new inode
743 * @dir: inode that is being walked from
744 * @dentry: dentry that is being walked to?
745 * @flags: lookup flags (unused)
746 *
747 */
748
749struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
750 unsigned int flags)
751{
752 struct dentry *res;
753 struct v9fs_session_info *v9ses;
754 struct p9_fid *dfid, *fid;
755 struct inode *inode;
756 const unsigned char *name;
757
758 p9_debug(P9_DEBUG_VFS, "dir: %p dentry: (%pd) %p flags: %x\n",
759 dir, dentry, dentry, flags);
760
761 if (dentry->d_name.len > NAME_MAX)
762 return ERR_PTR(-ENAMETOOLONG);
763
764 v9ses = v9fs_inode2v9ses(dir);
765 /* We can walk d_parent because we hold the dir->i_mutex */
766 dfid = v9fs_parent_fid(dentry);
767 if (IS_ERR(dfid))
768 return ERR_CAST(dfid);
769
770 /*
771 * Make sure we don't use a wrong inode due to parallel
772 * unlink. For cached mode create calls request for new
773 * inode. But with cache disabled, lookup should do this.
774 */
775 name = dentry->d_name.name;
776 fid = p9_client_walk(dfid, 1, &name, 1);
777 p9_fid_put(dfid);
778 if (fid == ERR_PTR(-ENOENT))
779 inode = NULL;
780 else if (IS_ERR(fid))
781 inode = ERR_CAST(fid);
782 else if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
783 inode = v9fs_get_inode_from_fid(v9ses, fid, dir->i_sb);
784 else
785 inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
786 /*
787 * If we had a rename on the server and a parallel lookup
788 * for the new name, then make sure we instantiate with
789 * the new name. ie look up for a/b, while on server somebody
790 * moved b under k and client parallely did a lookup for
791 * k/b.
792 */
793 res = d_splice_alias(inode, dentry);
794 if (!IS_ERR(fid)) {
795 if (!res)
796 v9fs_fid_add(dentry, &fid);
797 else if (!IS_ERR(res))
798 v9fs_fid_add(res, &fid);
799 else
800 p9_fid_put(fid);
801 }
802 return res;
803}
804
805static int
806v9fs_vfs_atomic_open(struct inode *dir, struct dentry *dentry,
807 struct file *file, unsigned int flags, umode_t mode)
808{
809 int err;
810 u32 perm;
811 struct v9fs_inode *v9inode;
812 struct v9fs_session_info *v9ses;
813 struct p9_fid *fid, *inode_fid;
814 struct dentry *res = NULL;
815 struct inode *inode;
816
817 if (d_in_lookup(dentry)) {
818 res = v9fs_vfs_lookup(dir, dentry, 0);
819 if (IS_ERR(res))
820 return PTR_ERR(res);
821
822 if (res)
823 dentry = res;
824 }
825
826 /* Only creates */
827 if (!(flags & O_CREAT) || d_really_is_positive(dentry))
828 return finish_no_open(file, res);
829
830 err = 0;
831
832 v9ses = v9fs_inode2v9ses(dir);
833 perm = unixmode2p9mode(v9ses, mode);
834 fid = v9fs_create(v9ses, dir, dentry, NULL, perm,
835 v9fs_uflags2omode(flags,
836 v9fs_proto_dotu(v9ses)));
837 if (IS_ERR(fid)) {
838 err = PTR_ERR(fid);
839 goto error;
840 }
841
842 v9fs_invalidate_inode_attr(dir);
843 inode = d_inode(dentry);
844 v9inode = V9FS_I(inode);
845 mutex_lock(&v9inode->v_mutex);
846 if ((v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) &&
847 !v9inode->writeback_fid &&
848 ((flags & O_ACCMODE) != O_RDONLY)) {
849 /*
850 * clone a fid and add it to writeback_fid
851 * we do it during open time instead of
852 * page dirty time via write_begin/page_mkwrite
853 * because we want write after unlink usecase
854 * to work.
855 */
856 inode_fid = v9fs_writeback_fid(dentry);
857 if (IS_ERR(inode_fid)) {
858 err = PTR_ERR(inode_fid);
859 mutex_unlock(&v9inode->v_mutex);
860 goto error;
861 }
862 v9inode->writeback_fid = (void *) inode_fid;
863 }
864 mutex_unlock(&v9inode->v_mutex);
865 err = finish_open(file, dentry, generic_file_open);
866 if (err)
867 goto error;
868
869 file->private_data = fid;
870 if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
871 fscache_use_cookie(v9fs_inode_cookie(v9inode),
872 file->f_mode & FMODE_WRITE);
873 v9fs_open_fid_add(inode, &fid);
874
875 file->f_mode |= FMODE_CREATED;
876out:
877 dput(res);
878 return err;
879
880error:
881 p9_fid_put(fid);
882 goto out;
883}
884
885/**
886 * v9fs_vfs_unlink - VFS unlink hook to delete an inode
887 * @i: inode that is being unlinked
888 * @d: dentry that is being unlinked
889 *
890 */
891
892int v9fs_vfs_unlink(struct inode *i, struct dentry *d)
893{
894 return v9fs_remove(i, d, 0);
895}
896
897/**
898 * v9fs_vfs_rmdir - VFS unlink hook to delete a directory
899 * @i: inode that is being unlinked
900 * @d: dentry that is being unlinked
901 *
902 */
903
904int v9fs_vfs_rmdir(struct inode *i, struct dentry *d)
905{
906 return v9fs_remove(i, d, AT_REMOVEDIR);
907}
908
909/**
910 * v9fs_vfs_rename - VFS hook to rename an inode
911 * @mnt_userns: The user namespace of the mount
912 * @old_dir: old dir inode
913 * @old_dentry: old dentry
914 * @new_dir: new dir inode
915 * @new_dentry: new dentry
916 * @flags: RENAME_* flags
917 *
918 */
919
920int
921v9fs_vfs_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
922 struct dentry *old_dentry, struct inode *new_dir,
923 struct dentry *new_dentry, unsigned int flags)
924{
925 int retval;
926 struct inode *old_inode;
927 struct inode *new_inode;
928 struct v9fs_session_info *v9ses;
929 struct p9_fid *oldfid = NULL, *dfid = NULL;
930 struct p9_fid *olddirfid = NULL;
931 struct p9_fid *newdirfid = NULL;
932 struct p9_wstat wstat;
933
934 if (flags)
935 return -EINVAL;
936
937 p9_debug(P9_DEBUG_VFS, "\n");
938 retval = 0;
939 old_inode = d_inode(old_dentry);
940 new_inode = d_inode(new_dentry);
941 v9ses = v9fs_inode2v9ses(old_inode);
942 oldfid = v9fs_fid_lookup(old_dentry);
943 if (IS_ERR(oldfid))
944 return PTR_ERR(oldfid);
945
946 dfid = v9fs_parent_fid(old_dentry);
947 olddirfid = clone_fid(dfid);
948 p9_fid_put(dfid);
949 dfid = NULL;
950
951 if (IS_ERR(olddirfid)) {
952 retval = PTR_ERR(olddirfid);
953 goto error;
954 }
955
956 dfid = v9fs_parent_fid(new_dentry);
957 newdirfid = clone_fid(dfid);
958 p9_fid_put(dfid);
959 dfid = NULL;
960
961 if (IS_ERR(newdirfid)) {
962 retval = PTR_ERR(newdirfid);
963 goto error;
964 }
965
966 down_write(&v9ses->rename_sem);
967 if (v9fs_proto_dotl(v9ses)) {
968 retval = p9_client_renameat(olddirfid, old_dentry->d_name.name,
969 newdirfid, new_dentry->d_name.name);
970 if (retval == -EOPNOTSUPP)
971 retval = p9_client_rename(oldfid, newdirfid,
972 new_dentry->d_name.name);
973 if (retval != -EOPNOTSUPP)
974 goto error_locked;
975 }
976 if (old_dentry->d_parent != new_dentry->d_parent) {
977 /*
978 * 9P .u can only handle file rename in the same directory
979 */
980
981 p9_debug(P9_DEBUG_ERROR, "old dir and new dir are different\n");
982 retval = -EXDEV;
983 goto error_locked;
984 }
985 v9fs_blank_wstat(&wstat);
986 wstat.muid = v9ses->uname;
987 wstat.name = new_dentry->d_name.name;
988 retval = p9_client_wstat(oldfid, &wstat);
989
990error_locked:
991 if (!retval) {
992 if (new_inode) {
993 if (S_ISDIR(new_inode->i_mode))
994 clear_nlink(new_inode);
995 else
996 v9fs_dec_count(new_inode);
997 }
998 if (S_ISDIR(old_inode->i_mode)) {
999 if (!new_inode)
1000 inc_nlink(new_dir);
1001 v9fs_dec_count(old_dir);
1002 }
1003 v9fs_invalidate_inode_attr(old_inode);
1004 v9fs_invalidate_inode_attr(old_dir);
1005 v9fs_invalidate_inode_attr(new_dir);
1006
1007 /* successful rename */
1008 d_move(old_dentry, new_dentry);
1009 }
1010 up_write(&v9ses->rename_sem);
1011
1012error:
1013 p9_fid_put(newdirfid);
1014 p9_fid_put(olddirfid);
1015 p9_fid_put(oldfid);
1016 return retval;
1017}
1018
1019/**
1020 * v9fs_vfs_getattr - retrieve file metadata
1021 * @mnt_userns: The user namespace of the mount
1022 * @path: Object to query
1023 * @stat: metadata structure to populate
1024 * @request_mask: Mask of STATX_xxx flags indicating the caller's interests
1025 * @flags: AT_STATX_xxx setting
1026 *
1027 */
1028
1029static int
1030v9fs_vfs_getattr(struct user_namespace *mnt_userns, const struct path *path,
1031 struct kstat *stat, u32 request_mask, unsigned int flags)
1032{
1033 struct dentry *dentry = path->dentry;
1034 struct v9fs_session_info *v9ses;
1035 struct p9_fid *fid;
1036 struct p9_wstat *st;
1037
1038 p9_debug(P9_DEBUG_VFS, "dentry: %p\n", dentry);
1039 v9ses = v9fs_dentry2v9ses(dentry);
1040 if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
1041 generic_fillattr(&init_user_ns, d_inode(dentry), stat);
1042 return 0;
1043 }
1044 fid = v9fs_fid_lookup(dentry);
1045 if (IS_ERR(fid))
1046 return PTR_ERR(fid);
1047
1048 st = p9_client_stat(fid);
1049 p9_fid_put(fid);
1050 if (IS_ERR(st))
1051 return PTR_ERR(st);
1052
1053 v9fs_stat2inode(st, d_inode(dentry), dentry->d_sb, 0);
1054 generic_fillattr(&init_user_ns, d_inode(dentry), stat);
1055
1056 p9stat_free(st);
1057 kfree(st);
1058 return 0;
1059}
1060
1061/**
1062 * v9fs_vfs_setattr - set file metadata
1063 * @mnt_userns: The user namespace of the mount
1064 * @dentry: file whose metadata to set
1065 * @iattr: metadata assignment structure
1066 *
1067 */
1068
1069static int v9fs_vfs_setattr(struct user_namespace *mnt_userns,
1070 struct dentry *dentry, struct iattr *iattr)
1071{
1072 int retval, use_dentry = 0;
1073 struct inode *inode = d_inode(dentry);
1074 struct v9fs_inode *v9inode = V9FS_I(inode);
1075 struct v9fs_session_info *v9ses;
1076 struct p9_fid *fid = NULL;
1077 struct p9_wstat wstat;
1078
1079 p9_debug(P9_DEBUG_VFS, "\n");
1080 retval = setattr_prepare(&init_user_ns, dentry, iattr);
1081 if (retval)
1082 return retval;
1083
1084 retval = -EPERM;
1085 v9ses = v9fs_dentry2v9ses(dentry);
1086 if (iattr->ia_valid & ATTR_FILE) {
1087 fid = iattr->ia_file->private_data;
1088 WARN_ON(!fid);
1089 }
1090 if (!fid) {
1091 fid = v9fs_fid_lookup(dentry);
1092 use_dentry = 1;
1093 }
1094 if (IS_ERR(fid))
1095 return PTR_ERR(fid);
1096
1097 v9fs_blank_wstat(&wstat);
1098 if (iattr->ia_valid & ATTR_MODE)
1099 wstat.mode = unixmode2p9mode(v9ses, iattr->ia_mode);
1100
1101 if (iattr->ia_valid & ATTR_MTIME)
1102 wstat.mtime = iattr->ia_mtime.tv_sec;
1103
1104 if (iattr->ia_valid & ATTR_ATIME)
1105 wstat.atime = iattr->ia_atime.tv_sec;
1106
1107 if (iattr->ia_valid & ATTR_SIZE)
1108 wstat.length = iattr->ia_size;
1109
1110 if (v9fs_proto_dotu(v9ses)) {
1111 if (iattr->ia_valid & ATTR_UID)
1112 wstat.n_uid = iattr->ia_uid;
1113
1114 if (iattr->ia_valid & ATTR_GID)
1115 wstat.n_gid = iattr->ia_gid;
1116 }
1117
1118 /* Write all dirty data */
1119 if (d_is_reg(dentry))
1120 filemap_write_and_wait(inode->i_mapping);
1121
1122 retval = p9_client_wstat(fid, &wstat);
1123
1124 if (use_dentry)
1125 p9_fid_put(fid);
1126
1127 if (retval < 0)
1128 return retval;
1129
1130 if ((iattr->ia_valid & ATTR_SIZE) &&
1131 iattr->ia_size != i_size_read(inode)) {
1132 truncate_setsize(inode, iattr->ia_size);
1133 fscache_resize_cookie(v9fs_inode_cookie(v9inode), iattr->ia_size);
1134 }
1135
1136 v9fs_invalidate_inode_attr(inode);
1137
1138 setattr_copy(&init_user_ns, inode, iattr);
1139 mark_inode_dirty(inode);
1140 return 0;
1141}
1142
1143/**
1144 * v9fs_stat2inode - populate an inode structure with mistat info
1145 * @stat: Plan 9 metadata (mistat) structure
1146 * @inode: inode to populate
1147 * @sb: superblock of filesystem
1148 * @flags: control flags (e.g. V9FS_STAT2INODE_KEEP_ISIZE)
1149 *
1150 */
1151
1152void
1153v9fs_stat2inode(struct p9_wstat *stat, struct inode *inode,
1154 struct super_block *sb, unsigned int flags)
1155{
1156 umode_t mode;
1157 struct v9fs_session_info *v9ses = sb->s_fs_info;
1158 struct v9fs_inode *v9inode = V9FS_I(inode);
1159
1160 set_nlink(inode, 1);
1161
1162 inode->i_atime.tv_sec = stat->atime;
1163 inode->i_mtime.tv_sec = stat->mtime;
1164 inode->i_ctime.tv_sec = stat->mtime;
1165
1166 inode->i_uid = v9ses->dfltuid;
1167 inode->i_gid = v9ses->dfltgid;
1168
1169 if (v9fs_proto_dotu(v9ses)) {
1170 inode->i_uid = stat->n_uid;
1171 inode->i_gid = stat->n_gid;
1172 }
1173 if ((S_ISREG(inode->i_mode)) || (S_ISDIR(inode->i_mode))) {
1174 if (v9fs_proto_dotu(v9ses)) {
1175 unsigned int i_nlink;
1176 /*
1177 * Hadlink support got added later to the .u extension.
1178 * So there can be a server out there that doesn't
1179 * support this even with .u extension. That would
1180 * just leave us with stat->extension being an empty
1181 * string, though.
1182 */
1183 /* HARDLINKCOUNT %u */
1184 if (sscanf(stat->extension,
1185 " HARDLINKCOUNT %u", &i_nlink) == 1)
1186 set_nlink(inode, i_nlink);
1187 }
1188 }
1189 mode = p9mode2perm(v9ses, stat);
1190 mode |= inode->i_mode & ~S_IALLUGO;
1191 inode->i_mode = mode;
1192
1193 if (!(flags & V9FS_STAT2INODE_KEEP_ISIZE))
1194 v9fs_i_size_write(inode, stat->length);
1195 /* not real number of blocks, but 512 byte ones ... */
1196 inode->i_blocks = (stat->length + 512 - 1) >> 9;
1197 v9inode->cache_validity &= ~V9FS_INO_INVALID_ATTR;
1198}
1199
1200/**
1201 * v9fs_qid2ino - convert qid into inode number
1202 * @qid: qid to hash
1203 *
1204 * BUG: potential for inode number collisions?
1205 */
1206
1207ino_t v9fs_qid2ino(struct p9_qid *qid)
1208{
1209 u64 path = qid->path + 2;
1210 ino_t i = 0;
1211
1212 if (sizeof(ino_t) == sizeof(path))
1213 memcpy(&i, &path, sizeof(ino_t));
1214 else
1215 i = (ino_t) (path ^ (path >> 32));
1216
1217 return i;
1218}
1219
1220/**
1221 * v9fs_vfs_get_link - follow a symlink path
1222 * @dentry: dentry for symlink
1223 * @inode: inode for symlink
1224 * @done: delayed call for when we are done with the return value
1225 */
1226
1227static const char *v9fs_vfs_get_link(struct dentry *dentry,
1228 struct inode *inode,
1229 struct delayed_call *done)
1230{
1231 struct v9fs_session_info *v9ses;
1232 struct p9_fid *fid;
1233 struct p9_wstat *st;
1234 char *res;
1235
1236 if (!dentry)
1237 return ERR_PTR(-ECHILD);
1238
1239 v9ses = v9fs_dentry2v9ses(dentry);
1240 if (!v9fs_proto_dotu(v9ses))
1241 return ERR_PTR(-EBADF);
1242
1243 p9_debug(P9_DEBUG_VFS, "%pd\n", dentry);
1244 fid = v9fs_fid_lookup(dentry);
1245
1246 if (IS_ERR(fid))
1247 return ERR_CAST(fid);
1248
1249 st = p9_client_stat(fid);
1250 p9_fid_put(fid);
1251 if (IS_ERR(st))
1252 return ERR_CAST(st);
1253
1254 if (!(st->mode & P9_DMSYMLINK)) {
1255 p9stat_free(st);
1256 kfree(st);
1257 return ERR_PTR(-EINVAL);
1258 }
1259 res = st->extension;
1260 st->extension = NULL;
1261 if (strlen(res) >= PATH_MAX)
1262 res[PATH_MAX - 1] = '\0';
1263
1264 p9stat_free(st);
1265 kfree(st);
1266 set_delayed_call(done, kfree_link, res);
1267 return res;
1268}
1269
1270/**
1271 * v9fs_vfs_mkspecial - create a special file
1272 * @dir: inode to create special file in
1273 * @dentry: dentry to create
1274 * @perm: mode to create special file
1275 * @extension: 9p2000.u format extension string representing special file
1276 *
1277 */
1278
1279static int v9fs_vfs_mkspecial(struct inode *dir, struct dentry *dentry,
1280 u32 perm, const char *extension)
1281{
1282 struct p9_fid *fid;
1283 struct v9fs_session_info *v9ses;
1284
1285 v9ses = v9fs_inode2v9ses(dir);
1286 if (!v9fs_proto_dotu(v9ses)) {
1287 p9_debug(P9_DEBUG_ERROR, "not extended\n");
1288 return -EPERM;
1289 }
1290
1291 fid = v9fs_create(v9ses, dir, dentry, (char *) extension, perm,
1292 P9_OREAD);
1293 if (IS_ERR(fid))
1294 return PTR_ERR(fid);
1295
1296 v9fs_invalidate_inode_attr(dir);
1297 p9_fid_put(fid);
1298 return 0;
1299}
1300
1301/**
1302 * v9fs_vfs_symlink - helper function to create symlinks
1303 * @mnt_userns: The user namespace of the mount
1304 * @dir: directory inode containing symlink
1305 * @dentry: dentry for symlink
1306 * @symname: symlink data
1307 *
1308 * See Also: 9P2000.u RFC for more information
1309 *
1310 */
1311
1312static int
1313v9fs_vfs_symlink(struct user_namespace *mnt_userns, struct inode *dir,
1314 struct dentry *dentry, const char *symname)
1315{
1316 p9_debug(P9_DEBUG_VFS, " %lu,%pd,%s\n",
1317 dir->i_ino, dentry, symname);
1318
1319 return v9fs_vfs_mkspecial(dir, dentry, P9_DMSYMLINK, symname);
1320}
1321
1322#define U32_MAX_DIGITS 10
1323
1324/**
1325 * v9fs_vfs_link - create a hardlink
1326 * @old_dentry: dentry for file to link to
1327 * @dir: inode destination for new link
1328 * @dentry: dentry for link
1329 *
1330 */
1331
1332static int
1333v9fs_vfs_link(struct dentry *old_dentry, struct inode *dir,
1334 struct dentry *dentry)
1335{
1336 int retval;
1337 char name[1 + U32_MAX_DIGITS + 2]; /* sign + number + \n + \0 */
1338 struct p9_fid *oldfid;
1339
1340 p9_debug(P9_DEBUG_VFS, " %lu,%pd,%pd\n",
1341 dir->i_ino, dentry, old_dentry);
1342
1343 oldfid = v9fs_fid_clone(old_dentry);
1344 if (IS_ERR(oldfid))
1345 return PTR_ERR(oldfid);
1346
1347 sprintf(name, "%d\n", oldfid->fid);
1348 retval = v9fs_vfs_mkspecial(dir, dentry, P9_DMLINK, name);
1349 if (!retval) {
1350 v9fs_refresh_inode(oldfid, d_inode(old_dentry));
1351 v9fs_invalidate_inode_attr(dir);
1352 }
1353 p9_fid_put(oldfid);
1354 return retval;
1355}
1356
1357/**
1358 * v9fs_vfs_mknod - create a special file
1359 * @mnt_userns: The user namespace of the mount
1360 * @dir: inode destination for new link
1361 * @dentry: dentry for file
1362 * @mode: mode for creation
1363 * @rdev: device associated with special file
1364 *
1365 */
1366
1367static int
1368v9fs_vfs_mknod(struct user_namespace *mnt_userns, struct inode *dir,
1369 struct dentry *dentry, umode_t mode, dev_t rdev)
1370{
1371 struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dir);
1372 int retval;
1373 char name[2 + U32_MAX_DIGITS + 1 + U32_MAX_DIGITS + 1];
1374 u32 perm;
1375
1376 p9_debug(P9_DEBUG_VFS, " %lu,%pd mode: %x MAJOR: %u MINOR: %u\n",
1377 dir->i_ino, dentry, mode,
1378 MAJOR(rdev), MINOR(rdev));
1379
1380 /* build extension */
1381 if (S_ISBLK(mode))
1382 sprintf(name, "b %u %u", MAJOR(rdev), MINOR(rdev));
1383 else if (S_ISCHR(mode))
1384 sprintf(name, "c %u %u", MAJOR(rdev), MINOR(rdev));
1385 else
1386 *name = 0;
1387
1388 perm = unixmode2p9mode(v9ses, mode);
1389 retval = v9fs_vfs_mkspecial(dir, dentry, perm, name);
1390
1391 return retval;
1392}
1393
1394int v9fs_refresh_inode(struct p9_fid *fid, struct inode *inode)
1395{
1396 int umode;
1397 dev_t rdev;
1398 struct p9_wstat *st;
1399 struct v9fs_session_info *v9ses;
1400 unsigned int flags;
1401
1402 v9ses = v9fs_inode2v9ses(inode);
1403 st = p9_client_stat(fid);
1404 if (IS_ERR(st))
1405 return PTR_ERR(st);
1406 /*
1407 * Don't update inode if the file type is different
1408 */
1409 umode = p9mode2unixmode(v9ses, st, &rdev);
1410 if (inode_wrong_type(inode, umode))
1411 goto out;
1412
1413 /*
1414 * We don't want to refresh inode->i_size,
1415 * because we may have cached data
1416 */
1417 flags = (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) ?
1418 V9FS_STAT2INODE_KEEP_ISIZE : 0;
1419 v9fs_stat2inode(st, inode, inode->i_sb, flags);
1420out:
1421 p9stat_free(st);
1422 kfree(st);
1423 return 0;
1424}
1425
1426static const struct inode_operations v9fs_dir_inode_operations_dotu = {
1427 .create = v9fs_vfs_create,
1428 .lookup = v9fs_vfs_lookup,
1429 .atomic_open = v9fs_vfs_atomic_open,
1430 .symlink = v9fs_vfs_symlink,
1431 .link = v9fs_vfs_link,
1432 .unlink = v9fs_vfs_unlink,
1433 .mkdir = v9fs_vfs_mkdir,
1434 .rmdir = v9fs_vfs_rmdir,
1435 .mknod = v9fs_vfs_mknod,
1436 .rename = v9fs_vfs_rename,
1437 .getattr = v9fs_vfs_getattr,
1438 .setattr = v9fs_vfs_setattr,
1439};
1440
1441static const struct inode_operations v9fs_dir_inode_operations = {
1442 .create = v9fs_vfs_create,
1443 .lookup = v9fs_vfs_lookup,
1444 .atomic_open = v9fs_vfs_atomic_open,
1445 .unlink = v9fs_vfs_unlink,
1446 .mkdir = v9fs_vfs_mkdir,
1447 .rmdir = v9fs_vfs_rmdir,
1448 .mknod = v9fs_vfs_mknod,
1449 .rename = v9fs_vfs_rename,
1450 .getattr = v9fs_vfs_getattr,
1451 .setattr = v9fs_vfs_setattr,
1452};
1453
1454static const struct inode_operations v9fs_file_inode_operations = {
1455 .getattr = v9fs_vfs_getattr,
1456 .setattr = v9fs_vfs_setattr,
1457};
1458
1459static const struct inode_operations v9fs_symlink_inode_operations = {
1460 .get_link = v9fs_vfs_get_link,
1461 .getattr = v9fs_vfs_getattr,
1462 .setattr = v9fs_vfs_setattr,
1463};
1464
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * linux/fs/9p/vfs_inode.c
4 *
5 * This file contains vfs inode ops for the 9P2000 protocol.
6 *
7 * Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
8 * Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
9 */
10
11#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
12
13#include <linux/module.h>
14#include <linux/errno.h>
15#include <linux/fs.h>
16#include <linux/file.h>
17#include <linux/pagemap.h>
18#include <linux/stat.h>
19#include <linux/string.h>
20#include <linux/inet.h>
21#include <linux/namei.h>
22#include <linux/idr.h>
23#include <linux/sched.h>
24#include <linux/slab.h>
25#include <linux/xattr.h>
26#include <linux/posix_acl.h>
27#include <net/9p/9p.h>
28#include <net/9p/client.h>
29
30#include "v9fs.h"
31#include "v9fs_vfs.h"
32#include "fid.h"
33#include "cache.h"
34#include "xattr.h"
35#include "acl.h"
36
37static const struct inode_operations v9fs_dir_inode_operations;
38static const struct inode_operations v9fs_dir_inode_operations_dotu;
39static const struct inode_operations v9fs_file_inode_operations;
40static const struct inode_operations v9fs_symlink_inode_operations;
41
42/**
43 * unixmode2p9mode - convert unix mode bits to plan 9
44 * @v9ses: v9fs session information
45 * @mode: mode to convert
46 *
47 */
48
49static u32 unixmode2p9mode(struct v9fs_session_info *v9ses, umode_t mode)
50{
51 int res;
52 res = mode & 0777;
53 if (S_ISDIR(mode))
54 res |= P9_DMDIR;
55 if (v9fs_proto_dotu(v9ses)) {
56 if (v9ses->nodev == 0) {
57 if (S_ISSOCK(mode))
58 res |= P9_DMSOCKET;
59 if (S_ISFIFO(mode))
60 res |= P9_DMNAMEDPIPE;
61 if (S_ISBLK(mode))
62 res |= P9_DMDEVICE;
63 if (S_ISCHR(mode))
64 res |= P9_DMDEVICE;
65 }
66
67 if ((mode & S_ISUID) == S_ISUID)
68 res |= P9_DMSETUID;
69 if ((mode & S_ISGID) == S_ISGID)
70 res |= P9_DMSETGID;
71 if ((mode & S_ISVTX) == S_ISVTX)
72 res |= P9_DMSETVTX;
73 }
74 return res;
75}
76
77/**
78 * p9mode2perm- convert plan9 mode bits to unix permission bits
79 * @v9ses: v9fs session information
80 * @stat: p9_wstat from which mode need to be derived
81 *
82 */
83static int p9mode2perm(struct v9fs_session_info *v9ses,
84 struct p9_wstat *stat)
85{
86 int res;
87 int mode = stat->mode;
88
89 res = mode & S_IALLUGO;
90 if (v9fs_proto_dotu(v9ses)) {
91 if ((mode & P9_DMSETUID) == P9_DMSETUID)
92 res |= S_ISUID;
93
94 if ((mode & P9_DMSETGID) == P9_DMSETGID)
95 res |= S_ISGID;
96
97 if ((mode & P9_DMSETVTX) == P9_DMSETVTX)
98 res |= S_ISVTX;
99 }
100 return res;
101}
102
103/**
104 * p9mode2unixmode- convert plan9 mode bits to unix mode bits
105 * @v9ses: v9fs session information
106 * @stat: p9_wstat from which mode need to be derived
107 * @rdev: major number, minor number in case of device files.
108 *
109 */
110static umode_t p9mode2unixmode(struct v9fs_session_info *v9ses,
111 struct p9_wstat *stat, dev_t *rdev)
112{
113 int res;
114 u32 mode = stat->mode;
115
116 *rdev = 0;
117 res = p9mode2perm(v9ses, stat);
118
119 if ((mode & P9_DMDIR) == P9_DMDIR)
120 res |= S_IFDIR;
121 else if ((mode & P9_DMSYMLINK) && (v9fs_proto_dotu(v9ses)))
122 res |= S_IFLNK;
123 else if ((mode & P9_DMSOCKET) && (v9fs_proto_dotu(v9ses))
124 && (v9ses->nodev == 0))
125 res |= S_IFSOCK;
126 else if ((mode & P9_DMNAMEDPIPE) && (v9fs_proto_dotu(v9ses))
127 && (v9ses->nodev == 0))
128 res |= S_IFIFO;
129 else if ((mode & P9_DMDEVICE) && (v9fs_proto_dotu(v9ses))
130 && (v9ses->nodev == 0)) {
131 char type = 0, ext[32];
132 int major = -1, minor = -1;
133
134 strlcpy(ext, stat->extension, sizeof(ext));
135 sscanf(ext, "%c %i %i", &type, &major, &minor);
136 switch (type) {
137 case 'c':
138 res |= S_IFCHR;
139 break;
140 case 'b':
141 res |= S_IFBLK;
142 break;
143 default:
144 p9_debug(P9_DEBUG_ERROR, "Unknown special type %c %s\n",
145 type, stat->extension);
146 };
147 *rdev = MKDEV(major, minor);
148 } else
149 res |= S_IFREG;
150
151 return res;
152}
153
154/**
155 * v9fs_uflags2omode- convert posix open flags to plan 9 mode bits
156 * @uflags: flags to convert
157 * @extended: if .u extensions are active
158 */
159
160int v9fs_uflags2omode(int uflags, int extended)
161{
162 int ret;
163
164 ret = 0;
165 switch (uflags&3) {
166 default:
167 case O_RDONLY:
168 ret = P9_OREAD;
169 break;
170
171 case O_WRONLY:
172 ret = P9_OWRITE;
173 break;
174
175 case O_RDWR:
176 ret = P9_ORDWR;
177 break;
178 }
179
180 if (extended) {
181 if (uflags & O_EXCL)
182 ret |= P9_OEXCL;
183
184 if (uflags & O_APPEND)
185 ret |= P9_OAPPEND;
186 }
187
188 return ret;
189}
190
191/**
192 * v9fs_blank_wstat - helper function to setup a 9P stat structure
193 * @wstat: structure to initialize
194 *
195 */
196
197void
198v9fs_blank_wstat(struct p9_wstat *wstat)
199{
200 wstat->type = ~0;
201 wstat->dev = ~0;
202 wstat->qid.type = ~0;
203 wstat->qid.version = ~0;
204 *((long long *)&wstat->qid.path) = ~0;
205 wstat->mode = ~0;
206 wstat->atime = ~0;
207 wstat->mtime = ~0;
208 wstat->length = ~0;
209 wstat->name = NULL;
210 wstat->uid = NULL;
211 wstat->gid = NULL;
212 wstat->muid = NULL;
213 wstat->n_uid = INVALID_UID;
214 wstat->n_gid = INVALID_GID;
215 wstat->n_muid = INVALID_UID;
216 wstat->extension = NULL;
217}
218
219/**
220 * v9fs_alloc_inode - helper function to allocate an inode
221 *
222 */
223struct inode *v9fs_alloc_inode(struct super_block *sb)
224{
225 struct v9fs_inode *v9inode;
226 v9inode = (struct v9fs_inode *)kmem_cache_alloc(v9fs_inode_cache,
227 GFP_KERNEL);
228 if (!v9inode)
229 return NULL;
230#ifdef CONFIG_9P_FSCACHE
231 v9inode->fscache = NULL;
232 mutex_init(&v9inode->fscache_lock);
233#endif
234 v9inode->writeback_fid = NULL;
235 v9inode->cache_validity = 0;
236 mutex_init(&v9inode->v_mutex);
237 return &v9inode->vfs_inode;
238}
239
240/**
241 * v9fs_free_inode - destroy an inode
242 *
243 */
244
245void v9fs_free_inode(struct inode *inode)
246{
247 kmem_cache_free(v9fs_inode_cache, V9FS_I(inode));
248}
249
250int v9fs_init_inode(struct v9fs_session_info *v9ses,
251 struct inode *inode, umode_t mode, dev_t rdev)
252{
253 int err = 0;
254
255 inode_init_owner(inode, NULL, mode);
256 inode->i_blocks = 0;
257 inode->i_rdev = rdev;
258 inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
259 inode->i_mapping->a_ops = &v9fs_addr_operations;
260
261 switch (mode & S_IFMT) {
262 case S_IFIFO:
263 case S_IFBLK:
264 case S_IFCHR:
265 case S_IFSOCK:
266 if (v9fs_proto_dotl(v9ses)) {
267 inode->i_op = &v9fs_file_inode_operations_dotl;
268 } else if (v9fs_proto_dotu(v9ses)) {
269 inode->i_op = &v9fs_file_inode_operations;
270 } else {
271 p9_debug(P9_DEBUG_ERROR,
272 "special files without extended mode\n");
273 err = -EINVAL;
274 goto error;
275 }
276 init_special_inode(inode, inode->i_mode, inode->i_rdev);
277 break;
278 case S_IFREG:
279 if (v9fs_proto_dotl(v9ses)) {
280 inode->i_op = &v9fs_file_inode_operations_dotl;
281 if (v9ses->cache == CACHE_LOOSE ||
282 v9ses->cache == CACHE_FSCACHE)
283 inode->i_fop =
284 &v9fs_cached_file_operations_dotl;
285 else if (v9ses->cache == CACHE_MMAP)
286 inode->i_fop = &v9fs_mmap_file_operations_dotl;
287 else
288 inode->i_fop = &v9fs_file_operations_dotl;
289 } else {
290 inode->i_op = &v9fs_file_inode_operations;
291 if (v9ses->cache == CACHE_LOOSE ||
292 v9ses->cache == CACHE_FSCACHE)
293 inode->i_fop =
294 &v9fs_cached_file_operations;
295 else if (v9ses->cache == CACHE_MMAP)
296 inode->i_fop = &v9fs_mmap_file_operations;
297 else
298 inode->i_fop = &v9fs_file_operations;
299 }
300
301 break;
302 case S_IFLNK:
303 if (!v9fs_proto_dotu(v9ses) && !v9fs_proto_dotl(v9ses)) {
304 p9_debug(P9_DEBUG_ERROR,
305 "extended modes used with legacy protocol\n");
306 err = -EINVAL;
307 goto error;
308 }
309
310 if (v9fs_proto_dotl(v9ses))
311 inode->i_op = &v9fs_symlink_inode_operations_dotl;
312 else
313 inode->i_op = &v9fs_symlink_inode_operations;
314
315 break;
316 case S_IFDIR:
317 inc_nlink(inode);
318 if (v9fs_proto_dotl(v9ses))
319 inode->i_op = &v9fs_dir_inode_operations_dotl;
320 else if (v9fs_proto_dotu(v9ses))
321 inode->i_op = &v9fs_dir_inode_operations_dotu;
322 else
323 inode->i_op = &v9fs_dir_inode_operations;
324
325 if (v9fs_proto_dotl(v9ses))
326 inode->i_fop = &v9fs_dir_operations_dotl;
327 else
328 inode->i_fop = &v9fs_dir_operations;
329
330 break;
331 default:
332 p9_debug(P9_DEBUG_ERROR, "BAD mode 0x%hx S_IFMT 0x%x\n",
333 mode, mode & S_IFMT);
334 err = -EINVAL;
335 goto error;
336 }
337error:
338 return err;
339
340}
341
342/**
343 * v9fs_get_inode - helper function to setup an inode
344 * @sb: superblock
345 * @mode: mode to setup inode with
346 *
347 */
348
349struct inode *v9fs_get_inode(struct super_block *sb, umode_t mode, dev_t rdev)
350{
351 int err;
352 struct inode *inode;
353 struct v9fs_session_info *v9ses = sb->s_fs_info;
354
355 p9_debug(P9_DEBUG_VFS, "super block: %p mode: %ho\n", sb, mode);
356
357 inode = new_inode(sb);
358 if (!inode) {
359 pr_warn("%s (%d): Problem allocating inode\n",
360 __func__, task_pid_nr(current));
361 return ERR_PTR(-ENOMEM);
362 }
363 err = v9fs_init_inode(v9ses, inode, mode, rdev);
364 if (err) {
365 iput(inode);
366 return ERR_PTR(err);
367 }
368 return inode;
369}
370
371/*
372static struct v9fs_fid*
373v9fs_clone_walk(struct v9fs_session_info *v9ses, u32 fid, struct dentry *dentry)
374{
375 int err;
376 int nfid;
377 struct v9fs_fid *ret;
378 struct v9fs_fcall *fcall;
379
380 nfid = v9fs_get_idpool(&v9ses->fidpool);
381 if (nfid < 0) {
382 eprintk(KERN_WARNING, "no free fids available\n");
383 return ERR_PTR(-ENOSPC);
384 }
385
386 err = v9fs_t_walk(v9ses, fid, nfid, (char *) dentry->d_name.name,
387 &fcall);
388
389 if (err < 0) {
390 if (fcall && fcall->id == RWALK)
391 goto clunk_fid;
392
393 PRINT_FCALL_ERROR("walk error", fcall);
394 v9fs_put_idpool(nfid, &v9ses->fidpool);
395 goto error;
396 }
397
398 kfree(fcall);
399 fcall = NULL;
400 ret = v9fs_fid_create(v9ses, nfid);
401 if (!ret) {
402 err = -ENOMEM;
403 goto clunk_fid;
404 }
405
406 err = v9fs_fid_insert(ret, dentry);
407 if (err < 0) {
408 v9fs_fid_destroy(ret);
409 goto clunk_fid;
410 }
411
412 return ret;
413
414clunk_fid:
415 v9fs_t_clunk(v9ses, nfid);
416
417error:
418 kfree(fcall);
419 return ERR_PTR(err);
420}
421*/
422
423
424/**
425 * v9fs_clear_inode - release an inode
426 * @inode: inode to release
427 *
428 */
429void v9fs_evict_inode(struct inode *inode)
430{
431 struct v9fs_inode *v9inode = V9FS_I(inode);
432
433 truncate_inode_pages_final(&inode->i_data);
434 clear_inode(inode);
435 filemap_fdatawrite(&inode->i_data);
436
437 v9fs_cache_inode_put_cookie(inode);
438 /* clunk the fid stashed in writeback_fid */
439 if (v9inode->writeback_fid) {
440 p9_client_clunk(v9inode->writeback_fid);
441 v9inode->writeback_fid = NULL;
442 }
443}
444
445static int v9fs_test_inode(struct inode *inode, void *data)
446{
447 int umode;
448 dev_t rdev;
449 struct v9fs_inode *v9inode = V9FS_I(inode);
450 struct p9_wstat *st = (struct p9_wstat *)data;
451 struct v9fs_session_info *v9ses = v9fs_inode2v9ses(inode);
452
453 umode = p9mode2unixmode(v9ses, st, &rdev);
454 /* don't match inode of different type */
455 if ((inode->i_mode & S_IFMT) != (umode & S_IFMT))
456 return 0;
457
458 /* compare qid details */
459 if (memcmp(&v9inode->qid.version,
460 &st->qid.version, sizeof(v9inode->qid.version)))
461 return 0;
462
463 if (v9inode->qid.type != st->qid.type)
464 return 0;
465
466 if (v9inode->qid.path != st->qid.path)
467 return 0;
468 return 1;
469}
470
471static int v9fs_test_new_inode(struct inode *inode, void *data)
472{
473 return 0;
474}
475
476static int v9fs_set_inode(struct inode *inode, void *data)
477{
478 struct v9fs_inode *v9inode = V9FS_I(inode);
479 struct p9_wstat *st = (struct p9_wstat *)data;
480
481 memcpy(&v9inode->qid, &st->qid, sizeof(st->qid));
482 return 0;
483}
484
485static struct inode *v9fs_qid_iget(struct super_block *sb,
486 struct p9_qid *qid,
487 struct p9_wstat *st,
488 int new)
489{
490 dev_t rdev;
491 int retval;
492 umode_t umode;
493 unsigned long i_ino;
494 struct inode *inode;
495 struct v9fs_session_info *v9ses = sb->s_fs_info;
496 int (*test)(struct inode *, void *);
497
498 if (new)
499 test = v9fs_test_new_inode;
500 else
501 test = v9fs_test_inode;
502
503 i_ino = v9fs_qid2ino(qid);
504 inode = iget5_locked(sb, i_ino, test, v9fs_set_inode, st);
505 if (!inode)
506 return ERR_PTR(-ENOMEM);
507 if (!(inode->i_state & I_NEW))
508 return inode;
509 /*
510 * initialize the inode with the stat info
511 * FIXME!! we may need support for stale inodes
512 * later.
513 */
514 inode->i_ino = i_ino;
515 umode = p9mode2unixmode(v9ses, st, &rdev);
516 retval = v9fs_init_inode(v9ses, inode, umode, rdev);
517 if (retval)
518 goto error;
519
520 v9fs_stat2inode(st, inode, sb, 0);
521 v9fs_cache_inode_get_cookie(inode);
522 unlock_new_inode(inode);
523 return inode;
524error:
525 iget_failed(inode);
526 return ERR_PTR(retval);
527
528}
529
530struct inode *
531v9fs_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid,
532 struct super_block *sb, int new)
533{
534 struct p9_wstat *st;
535 struct inode *inode = NULL;
536
537 st = p9_client_stat(fid);
538 if (IS_ERR(st))
539 return ERR_CAST(st);
540
541 inode = v9fs_qid_iget(sb, &st->qid, st, new);
542 p9stat_free(st);
543 kfree(st);
544 return inode;
545}
546
547/**
548 * v9fs_at_to_dotl_flags- convert Linux specific AT flags to
549 * plan 9 AT flag.
550 * @flags: flags to convert
551 */
552static int v9fs_at_to_dotl_flags(int flags)
553{
554 int rflags = 0;
555 if (flags & AT_REMOVEDIR)
556 rflags |= P9_DOTL_AT_REMOVEDIR;
557 return rflags;
558}
559
560/**
561 * v9fs_dec_count - helper functon to drop i_nlink.
562 *
563 * If a directory had nlink <= 2 (including . and ..), then we should not drop
564 * the link count, which indicates the underlying exported fs doesn't maintain
565 * nlink accurately. e.g.
566 * - overlayfs sets nlink to 1 for merged dir
567 * - ext4 (with dir_nlink feature enabled) sets nlink to 1 if a dir has more
568 * than EXT4_LINK_MAX (65000) links.
569 *
570 * @inode: inode whose nlink is being dropped
571 */
572static void v9fs_dec_count(struct inode *inode)
573{
574 if (!S_ISDIR(inode->i_mode) || inode->i_nlink > 2)
575 drop_nlink(inode);
576}
577
578/**
579 * v9fs_remove - helper function to remove files and directories
580 * @dir: directory inode that is being deleted
581 * @dentry: dentry that is being deleted
582 * @flags: removing a directory
583 *
584 */
585
586static int v9fs_remove(struct inode *dir, struct dentry *dentry, int flags)
587{
588 struct inode *inode;
589 int retval = -EOPNOTSUPP;
590 struct p9_fid *v9fid, *dfid;
591 struct v9fs_session_info *v9ses;
592
593 p9_debug(P9_DEBUG_VFS, "inode: %p dentry: %p rmdir: %x\n",
594 dir, dentry, flags);
595
596 v9ses = v9fs_inode2v9ses(dir);
597 inode = d_inode(dentry);
598 dfid = v9fs_parent_fid(dentry);
599 if (IS_ERR(dfid)) {
600 retval = PTR_ERR(dfid);
601 p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", retval);
602 return retval;
603 }
604 if (v9fs_proto_dotl(v9ses))
605 retval = p9_client_unlinkat(dfid, dentry->d_name.name,
606 v9fs_at_to_dotl_flags(flags));
607 if (retval == -EOPNOTSUPP) {
608 /* Try the one based on path */
609 v9fid = v9fs_fid_clone(dentry);
610 if (IS_ERR(v9fid))
611 return PTR_ERR(v9fid);
612 retval = p9_client_remove(v9fid);
613 }
614 if (!retval) {
615 /*
616 * directories on unlink should have zero
617 * link count
618 */
619 if (flags & AT_REMOVEDIR) {
620 clear_nlink(inode);
621 v9fs_dec_count(dir);
622 } else
623 v9fs_dec_count(inode);
624
625 v9fs_invalidate_inode_attr(inode);
626 v9fs_invalidate_inode_attr(dir);
627 }
628 return retval;
629}
630
631/**
632 * v9fs_create - Create a file
633 * @v9ses: session information
634 * @dir: directory that dentry is being created in
635 * @dentry: dentry that is being created
636 * @extension: 9p2000.u extension string to support devices, etc.
637 * @perm: create permissions
638 * @mode: open mode
639 *
640 */
641static struct p9_fid *
642v9fs_create(struct v9fs_session_info *v9ses, struct inode *dir,
643 struct dentry *dentry, char *extension, u32 perm, u8 mode)
644{
645 int err;
646 const unsigned char *name;
647 struct p9_fid *dfid, *ofid, *fid;
648 struct inode *inode;
649
650 p9_debug(P9_DEBUG_VFS, "name %pd\n", dentry);
651
652 err = 0;
653 ofid = NULL;
654 fid = NULL;
655 name = dentry->d_name.name;
656 dfid = v9fs_parent_fid(dentry);
657 if (IS_ERR(dfid)) {
658 err = PTR_ERR(dfid);
659 p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
660 return ERR_PTR(err);
661 }
662
663 /* clone a fid to use for creation */
664 ofid = clone_fid(dfid);
665 if (IS_ERR(ofid)) {
666 err = PTR_ERR(ofid);
667 p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
668 return ERR_PTR(err);
669 }
670
671 err = p9_client_fcreate(ofid, name, perm, mode, extension);
672 if (err < 0) {
673 p9_debug(P9_DEBUG_VFS, "p9_client_fcreate failed %d\n", err);
674 goto error;
675 }
676
677 if (!(perm & P9_DMLINK)) {
678 /* now walk from the parent so we can get unopened fid */
679 fid = p9_client_walk(dfid, 1, &name, 1);
680 if (IS_ERR(fid)) {
681 err = PTR_ERR(fid);
682 p9_debug(P9_DEBUG_VFS,
683 "p9_client_walk failed %d\n", err);
684 fid = NULL;
685 goto error;
686 }
687 /*
688 * instantiate inode and assign the unopened fid to the dentry
689 */
690 inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
691 if (IS_ERR(inode)) {
692 err = PTR_ERR(inode);
693 p9_debug(P9_DEBUG_VFS,
694 "inode creation failed %d\n", err);
695 goto error;
696 }
697 v9fs_fid_add(dentry, fid);
698 d_instantiate(dentry, inode);
699 }
700 return ofid;
701error:
702 if (ofid)
703 p9_client_clunk(ofid);
704
705 if (fid)
706 p9_client_clunk(fid);
707
708 return ERR_PTR(err);
709}
710
711/**
712 * v9fs_vfs_create - VFS hook to create a regular file
713 *
714 * open(.., O_CREAT) is handled in v9fs_vfs_atomic_open(). This is only called
715 * for mknod(2).
716 *
717 * @dir: directory inode that is being created
718 * @dentry: dentry that is being deleted
719 * @mode: create permissions
720 *
721 */
722
723static int
724v9fs_vfs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
725 bool excl)
726{
727 struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dir);
728 u32 perm = unixmode2p9mode(v9ses, mode);
729 struct p9_fid *fid;
730
731 /* P9_OEXCL? */
732 fid = v9fs_create(v9ses, dir, dentry, NULL, perm, P9_ORDWR);
733 if (IS_ERR(fid))
734 return PTR_ERR(fid);
735
736 v9fs_invalidate_inode_attr(dir);
737 p9_client_clunk(fid);
738
739 return 0;
740}
741
742/**
743 * v9fs_vfs_mkdir - VFS mkdir hook to create a directory
744 * @dir: inode that is being unlinked
745 * @dentry: dentry that is being unlinked
746 * @mode: mode for new directory
747 *
748 */
749
750static int v9fs_vfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
751{
752 int err;
753 u32 perm;
754 struct p9_fid *fid;
755 struct v9fs_session_info *v9ses;
756
757 p9_debug(P9_DEBUG_VFS, "name %pd\n", dentry);
758 err = 0;
759 v9ses = v9fs_inode2v9ses(dir);
760 perm = unixmode2p9mode(v9ses, mode | S_IFDIR);
761 fid = v9fs_create(v9ses, dir, dentry, NULL, perm, P9_OREAD);
762 if (IS_ERR(fid)) {
763 err = PTR_ERR(fid);
764 fid = NULL;
765 } else {
766 inc_nlink(dir);
767 v9fs_invalidate_inode_attr(dir);
768 }
769
770 if (fid)
771 p9_client_clunk(fid);
772
773 return err;
774}
775
776/**
777 * v9fs_vfs_lookup - VFS lookup hook to "walk" to a new inode
778 * @dir: inode that is being walked from
779 * @dentry: dentry that is being walked to?
780 * @flags: lookup flags (unused)
781 *
782 */
783
784struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
785 unsigned int flags)
786{
787 struct dentry *res;
788 struct v9fs_session_info *v9ses;
789 struct p9_fid *dfid, *fid;
790 struct inode *inode;
791 const unsigned char *name;
792
793 p9_debug(P9_DEBUG_VFS, "dir: %p dentry: (%pd) %p flags: %x\n",
794 dir, dentry, dentry, flags);
795
796 if (dentry->d_name.len > NAME_MAX)
797 return ERR_PTR(-ENAMETOOLONG);
798
799 v9ses = v9fs_inode2v9ses(dir);
800 /* We can walk d_parent because we hold the dir->i_mutex */
801 dfid = v9fs_parent_fid(dentry);
802 if (IS_ERR(dfid))
803 return ERR_CAST(dfid);
804
805 /*
806 * Make sure we don't use a wrong inode due to parallel
807 * unlink. For cached mode create calls request for new
808 * inode. But with cache disabled, lookup should do this.
809 */
810 name = dentry->d_name.name;
811 fid = p9_client_walk(dfid, 1, &name, 1);
812 if (fid == ERR_PTR(-ENOENT))
813 inode = NULL;
814 else if (IS_ERR(fid))
815 inode = ERR_CAST(fid);
816 else if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
817 inode = v9fs_get_inode_from_fid(v9ses, fid, dir->i_sb);
818 else
819 inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
820 /*
821 * If we had a rename on the server and a parallel lookup
822 * for the new name, then make sure we instantiate with
823 * the new name. ie look up for a/b, while on server somebody
824 * moved b under k and client parallely did a lookup for
825 * k/b.
826 */
827 res = d_splice_alias(inode, dentry);
828 if (!IS_ERR(fid)) {
829 if (!res)
830 v9fs_fid_add(dentry, fid);
831 else if (!IS_ERR(res))
832 v9fs_fid_add(res, fid);
833 else
834 p9_client_clunk(fid);
835 }
836 return res;
837}
838
839static int
840v9fs_vfs_atomic_open(struct inode *dir, struct dentry *dentry,
841 struct file *file, unsigned flags, umode_t mode)
842{
843 int err;
844 u32 perm;
845 struct v9fs_inode *v9inode;
846 struct v9fs_session_info *v9ses;
847 struct p9_fid *fid, *inode_fid;
848 struct dentry *res = NULL;
849
850 if (d_in_lookup(dentry)) {
851 res = v9fs_vfs_lookup(dir, dentry, 0);
852 if (IS_ERR(res))
853 return PTR_ERR(res);
854
855 if (res)
856 dentry = res;
857 }
858
859 /* Only creates */
860 if (!(flags & O_CREAT) || d_really_is_positive(dentry))
861 return finish_no_open(file, res);
862
863 err = 0;
864
865 v9ses = v9fs_inode2v9ses(dir);
866 perm = unixmode2p9mode(v9ses, mode);
867 fid = v9fs_create(v9ses, dir, dentry, NULL, perm,
868 v9fs_uflags2omode(flags,
869 v9fs_proto_dotu(v9ses)));
870 if (IS_ERR(fid)) {
871 err = PTR_ERR(fid);
872 fid = NULL;
873 goto error;
874 }
875
876 v9fs_invalidate_inode_attr(dir);
877 v9inode = V9FS_I(d_inode(dentry));
878 mutex_lock(&v9inode->v_mutex);
879 if ((v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) &&
880 !v9inode->writeback_fid &&
881 ((flags & O_ACCMODE) != O_RDONLY)) {
882 /*
883 * clone a fid and add it to writeback_fid
884 * we do it during open time instead of
885 * page dirty time via write_begin/page_mkwrite
886 * because we want write after unlink usecase
887 * to work.
888 */
889 inode_fid = v9fs_writeback_fid(dentry);
890 if (IS_ERR(inode_fid)) {
891 err = PTR_ERR(inode_fid);
892 mutex_unlock(&v9inode->v_mutex);
893 goto error;
894 }
895 v9inode->writeback_fid = (void *) inode_fid;
896 }
897 mutex_unlock(&v9inode->v_mutex);
898 err = finish_open(file, dentry, generic_file_open);
899 if (err)
900 goto error;
901
902 file->private_data = fid;
903 if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
904 v9fs_cache_inode_set_cookie(d_inode(dentry), file);
905
906 file->f_mode |= FMODE_CREATED;
907out:
908 dput(res);
909 return err;
910
911error:
912 if (fid)
913 p9_client_clunk(fid);
914 goto out;
915}
916
917/**
918 * v9fs_vfs_unlink - VFS unlink hook to delete an inode
919 * @i: inode that is being unlinked
920 * @d: dentry that is being unlinked
921 *
922 */
923
924int v9fs_vfs_unlink(struct inode *i, struct dentry *d)
925{
926 return v9fs_remove(i, d, 0);
927}
928
929/**
930 * v9fs_vfs_rmdir - VFS unlink hook to delete a directory
931 * @i: inode that is being unlinked
932 * @d: dentry that is being unlinked
933 *
934 */
935
936int v9fs_vfs_rmdir(struct inode *i, struct dentry *d)
937{
938 return v9fs_remove(i, d, AT_REMOVEDIR);
939}
940
941/**
942 * v9fs_vfs_rename - VFS hook to rename an inode
943 * @old_dir: old dir inode
944 * @old_dentry: old dentry
945 * @new_dir: new dir inode
946 * @new_dentry: new dentry
947 *
948 */
949
950int
951v9fs_vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
952 struct inode *new_dir, struct dentry *new_dentry,
953 unsigned int flags)
954{
955 int retval;
956 struct inode *old_inode;
957 struct inode *new_inode;
958 struct v9fs_session_info *v9ses;
959 struct p9_fid *oldfid;
960 struct p9_fid *olddirfid;
961 struct p9_fid *newdirfid;
962 struct p9_wstat wstat;
963
964 if (flags)
965 return -EINVAL;
966
967 p9_debug(P9_DEBUG_VFS, "\n");
968 retval = 0;
969 old_inode = d_inode(old_dentry);
970 new_inode = d_inode(new_dentry);
971 v9ses = v9fs_inode2v9ses(old_inode);
972 oldfid = v9fs_fid_lookup(old_dentry);
973 if (IS_ERR(oldfid))
974 return PTR_ERR(oldfid);
975
976 olddirfid = clone_fid(v9fs_parent_fid(old_dentry));
977 if (IS_ERR(olddirfid)) {
978 retval = PTR_ERR(olddirfid);
979 goto done;
980 }
981
982 newdirfid = clone_fid(v9fs_parent_fid(new_dentry));
983 if (IS_ERR(newdirfid)) {
984 retval = PTR_ERR(newdirfid);
985 goto clunk_olddir;
986 }
987
988 down_write(&v9ses->rename_sem);
989 if (v9fs_proto_dotl(v9ses)) {
990 retval = p9_client_renameat(olddirfid, old_dentry->d_name.name,
991 newdirfid, new_dentry->d_name.name);
992 if (retval == -EOPNOTSUPP)
993 retval = p9_client_rename(oldfid, newdirfid,
994 new_dentry->d_name.name);
995 if (retval != -EOPNOTSUPP)
996 goto clunk_newdir;
997 }
998 if (old_dentry->d_parent != new_dentry->d_parent) {
999 /*
1000 * 9P .u can only handle file rename in the same directory
1001 */
1002
1003 p9_debug(P9_DEBUG_ERROR, "old dir and new dir are different\n");
1004 retval = -EXDEV;
1005 goto clunk_newdir;
1006 }
1007 v9fs_blank_wstat(&wstat);
1008 wstat.muid = v9ses->uname;
1009 wstat.name = new_dentry->d_name.name;
1010 retval = p9_client_wstat(oldfid, &wstat);
1011
1012clunk_newdir:
1013 if (!retval) {
1014 if (new_inode) {
1015 if (S_ISDIR(new_inode->i_mode))
1016 clear_nlink(new_inode);
1017 else
1018 v9fs_dec_count(new_inode);
1019 }
1020 if (S_ISDIR(old_inode->i_mode)) {
1021 if (!new_inode)
1022 inc_nlink(new_dir);
1023 v9fs_dec_count(old_dir);
1024 }
1025 v9fs_invalidate_inode_attr(old_inode);
1026 v9fs_invalidate_inode_attr(old_dir);
1027 v9fs_invalidate_inode_attr(new_dir);
1028
1029 /* successful rename */
1030 d_move(old_dentry, new_dentry);
1031 }
1032 up_write(&v9ses->rename_sem);
1033 p9_client_clunk(newdirfid);
1034
1035clunk_olddir:
1036 p9_client_clunk(olddirfid);
1037
1038done:
1039 return retval;
1040}
1041
1042/**
1043 * v9fs_vfs_getattr - retrieve file metadata
1044 * @path: Object to query
1045 * @stat: metadata structure to populate
1046 * @request_mask: Mask of STATX_xxx flags indicating the caller's interests
1047 * @flags: AT_STATX_xxx setting
1048 *
1049 */
1050
1051static int
1052v9fs_vfs_getattr(const struct path *path, struct kstat *stat,
1053 u32 request_mask, unsigned int flags)
1054{
1055 struct dentry *dentry = path->dentry;
1056 struct v9fs_session_info *v9ses;
1057 struct p9_fid *fid;
1058 struct p9_wstat *st;
1059
1060 p9_debug(P9_DEBUG_VFS, "dentry: %p\n", dentry);
1061 v9ses = v9fs_dentry2v9ses(dentry);
1062 if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
1063 generic_fillattr(d_inode(dentry), stat);
1064 return 0;
1065 }
1066 fid = v9fs_fid_lookup(dentry);
1067 if (IS_ERR(fid))
1068 return PTR_ERR(fid);
1069
1070 st = p9_client_stat(fid);
1071 if (IS_ERR(st))
1072 return PTR_ERR(st);
1073
1074 v9fs_stat2inode(st, d_inode(dentry), dentry->d_sb, 0);
1075 generic_fillattr(d_inode(dentry), stat);
1076
1077 p9stat_free(st);
1078 kfree(st);
1079 return 0;
1080}
1081
1082/**
1083 * v9fs_vfs_setattr - set file metadata
1084 * @dentry: file whose metadata to set
1085 * @iattr: metadata assignment structure
1086 *
1087 */
1088
1089static int v9fs_vfs_setattr(struct dentry *dentry, struct iattr *iattr)
1090{
1091 int retval;
1092 struct v9fs_session_info *v9ses;
1093 struct p9_fid *fid;
1094 struct p9_wstat wstat;
1095
1096 p9_debug(P9_DEBUG_VFS, "\n");
1097 retval = setattr_prepare(dentry, iattr);
1098 if (retval)
1099 return retval;
1100
1101 retval = -EPERM;
1102 v9ses = v9fs_dentry2v9ses(dentry);
1103 fid = v9fs_fid_lookup(dentry);
1104 if(IS_ERR(fid))
1105 return PTR_ERR(fid);
1106
1107 v9fs_blank_wstat(&wstat);
1108 if (iattr->ia_valid & ATTR_MODE)
1109 wstat.mode = unixmode2p9mode(v9ses, iattr->ia_mode);
1110
1111 if (iattr->ia_valid & ATTR_MTIME)
1112 wstat.mtime = iattr->ia_mtime.tv_sec;
1113
1114 if (iattr->ia_valid & ATTR_ATIME)
1115 wstat.atime = iattr->ia_atime.tv_sec;
1116
1117 if (iattr->ia_valid & ATTR_SIZE)
1118 wstat.length = iattr->ia_size;
1119
1120 if (v9fs_proto_dotu(v9ses)) {
1121 if (iattr->ia_valid & ATTR_UID)
1122 wstat.n_uid = iattr->ia_uid;
1123
1124 if (iattr->ia_valid & ATTR_GID)
1125 wstat.n_gid = iattr->ia_gid;
1126 }
1127
1128 /* Write all dirty data */
1129 if (d_is_reg(dentry))
1130 filemap_write_and_wait(d_inode(dentry)->i_mapping);
1131
1132 retval = p9_client_wstat(fid, &wstat);
1133 if (retval < 0)
1134 return retval;
1135
1136 if ((iattr->ia_valid & ATTR_SIZE) &&
1137 iattr->ia_size != i_size_read(d_inode(dentry)))
1138 truncate_setsize(d_inode(dentry), iattr->ia_size);
1139
1140 v9fs_invalidate_inode_attr(d_inode(dentry));
1141
1142 setattr_copy(d_inode(dentry), iattr);
1143 mark_inode_dirty(d_inode(dentry));
1144 return 0;
1145}
1146
1147/**
1148 * v9fs_stat2inode - populate an inode structure with mistat info
1149 * @stat: Plan 9 metadata (mistat) structure
1150 * @inode: inode to populate
1151 * @sb: superblock of filesystem
1152 * @flags: control flags (e.g. V9FS_STAT2INODE_KEEP_ISIZE)
1153 *
1154 */
1155
1156void
1157v9fs_stat2inode(struct p9_wstat *stat, struct inode *inode,
1158 struct super_block *sb, unsigned int flags)
1159{
1160 umode_t mode;
1161 char ext[32];
1162 char tag_name[14];
1163 unsigned int i_nlink;
1164 struct v9fs_session_info *v9ses = sb->s_fs_info;
1165 struct v9fs_inode *v9inode = V9FS_I(inode);
1166
1167 set_nlink(inode, 1);
1168
1169 inode->i_atime.tv_sec = stat->atime;
1170 inode->i_mtime.tv_sec = stat->mtime;
1171 inode->i_ctime.tv_sec = stat->mtime;
1172
1173 inode->i_uid = v9ses->dfltuid;
1174 inode->i_gid = v9ses->dfltgid;
1175
1176 if (v9fs_proto_dotu(v9ses)) {
1177 inode->i_uid = stat->n_uid;
1178 inode->i_gid = stat->n_gid;
1179 }
1180 if ((S_ISREG(inode->i_mode)) || (S_ISDIR(inode->i_mode))) {
1181 if (v9fs_proto_dotu(v9ses) && (stat->extension[0] != '\0')) {
1182 /*
1183 * Hadlink support got added later to
1184 * to the .u extension. So there can be
1185 * server out there that doesn't support
1186 * this even with .u extension. So check
1187 * for non NULL stat->extension
1188 */
1189 strlcpy(ext, stat->extension, sizeof(ext));
1190 /* HARDLINKCOUNT %u */
1191 sscanf(ext, "%13s %u", tag_name, &i_nlink);
1192 if (!strncmp(tag_name, "HARDLINKCOUNT", 13))
1193 set_nlink(inode, i_nlink);
1194 }
1195 }
1196 mode = p9mode2perm(v9ses, stat);
1197 mode |= inode->i_mode & ~S_IALLUGO;
1198 inode->i_mode = mode;
1199
1200 if (!(flags & V9FS_STAT2INODE_KEEP_ISIZE))
1201 v9fs_i_size_write(inode, stat->length);
1202 /* not real number of blocks, but 512 byte ones ... */
1203 inode->i_blocks = (stat->length + 512 - 1) >> 9;
1204 v9inode->cache_validity &= ~V9FS_INO_INVALID_ATTR;
1205}
1206
1207/**
1208 * v9fs_qid2ino - convert qid into inode number
1209 * @qid: qid to hash
1210 *
1211 * BUG: potential for inode number collisions?
1212 */
1213
1214ino_t v9fs_qid2ino(struct p9_qid *qid)
1215{
1216 u64 path = qid->path + 2;
1217 ino_t i = 0;
1218
1219 if (sizeof(ino_t) == sizeof(path))
1220 memcpy(&i, &path, sizeof(ino_t));
1221 else
1222 i = (ino_t) (path ^ (path >> 32));
1223
1224 return i;
1225}
1226
1227/**
1228 * v9fs_vfs_get_link - follow a symlink path
1229 * @dentry: dentry for symlink
1230 * @inode: inode for symlink
1231 * @done: delayed call for when we are done with the return value
1232 */
1233
1234static const char *v9fs_vfs_get_link(struct dentry *dentry,
1235 struct inode *inode,
1236 struct delayed_call *done)
1237{
1238 struct v9fs_session_info *v9ses;
1239 struct p9_fid *fid;
1240 struct p9_wstat *st;
1241 char *res;
1242
1243 if (!dentry)
1244 return ERR_PTR(-ECHILD);
1245
1246 v9ses = v9fs_dentry2v9ses(dentry);
1247 fid = v9fs_fid_lookup(dentry);
1248 p9_debug(P9_DEBUG_VFS, "%pd\n", dentry);
1249
1250 if (IS_ERR(fid))
1251 return ERR_CAST(fid);
1252
1253 if (!v9fs_proto_dotu(v9ses))
1254 return ERR_PTR(-EBADF);
1255
1256 st = p9_client_stat(fid);
1257 if (IS_ERR(st))
1258 return ERR_CAST(st);
1259
1260 if (!(st->mode & P9_DMSYMLINK)) {
1261 p9stat_free(st);
1262 kfree(st);
1263 return ERR_PTR(-EINVAL);
1264 }
1265 res = st->extension;
1266 st->extension = NULL;
1267 if (strlen(res) >= PATH_MAX)
1268 res[PATH_MAX - 1] = '\0';
1269
1270 p9stat_free(st);
1271 kfree(st);
1272 set_delayed_call(done, kfree_link, res);
1273 return res;
1274}
1275
1276/**
1277 * v9fs_vfs_mkspecial - create a special file
1278 * @dir: inode to create special file in
1279 * @dentry: dentry to create
1280 * @perm: mode to create special file
1281 * @extension: 9p2000.u format extension string representing special file
1282 *
1283 */
1284
1285static int v9fs_vfs_mkspecial(struct inode *dir, struct dentry *dentry,
1286 u32 perm, const char *extension)
1287{
1288 struct p9_fid *fid;
1289 struct v9fs_session_info *v9ses;
1290
1291 v9ses = v9fs_inode2v9ses(dir);
1292 if (!v9fs_proto_dotu(v9ses)) {
1293 p9_debug(P9_DEBUG_ERROR, "not extended\n");
1294 return -EPERM;
1295 }
1296
1297 fid = v9fs_create(v9ses, dir, dentry, (char *) extension, perm,
1298 P9_OREAD);
1299 if (IS_ERR(fid))
1300 return PTR_ERR(fid);
1301
1302 v9fs_invalidate_inode_attr(dir);
1303 p9_client_clunk(fid);
1304 return 0;
1305}
1306
1307/**
1308 * v9fs_vfs_symlink - helper function to create symlinks
1309 * @dir: directory inode containing symlink
1310 * @dentry: dentry for symlink
1311 * @symname: symlink data
1312 *
1313 * See Also: 9P2000.u RFC for more information
1314 *
1315 */
1316
1317static int
1318v9fs_vfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname)
1319{
1320 p9_debug(P9_DEBUG_VFS, " %lu,%pd,%s\n",
1321 dir->i_ino, dentry, symname);
1322
1323 return v9fs_vfs_mkspecial(dir, dentry, P9_DMSYMLINK, symname);
1324}
1325
1326#define U32_MAX_DIGITS 10
1327
1328/**
1329 * v9fs_vfs_link - create a hardlink
1330 * @old_dentry: dentry for file to link to
1331 * @dir: inode destination for new link
1332 * @dentry: dentry for link
1333 *
1334 */
1335
1336static int
1337v9fs_vfs_link(struct dentry *old_dentry, struct inode *dir,
1338 struct dentry *dentry)
1339{
1340 int retval;
1341 char name[1 + U32_MAX_DIGITS + 2]; /* sign + number + \n + \0 */
1342 struct p9_fid *oldfid;
1343
1344 p9_debug(P9_DEBUG_VFS, " %lu,%pd,%pd\n",
1345 dir->i_ino, dentry, old_dentry);
1346
1347 oldfid = v9fs_fid_clone(old_dentry);
1348 if (IS_ERR(oldfid))
1349 return PTR_ERR(oldfid);
1350
1351 sprintf(name, "%d\n", oldfid->fid);
1352 retval = v9fs_vfs_mkspecial(dir, dentry, P9_DMLINK, name);
1353 if (!retval) {
1354 v9fs_refresh_inode(oldfid, d_inode(old_dentry));
1355 v9fs_invalidate_inode_attr(dir);
1356 }
1357 p9_client_clunk(oldfid);
1358 return retval;
1359}
1360
1361/**
1362 * v9fs_vfs_mknod - create a special file
1363 * @dir: inode destination for new link
1364 * @dentry: dentry for file
1365 * @mode: mode for creation
1366 * @rdev: device associated with special file
1367 *
1368 */
1369
1370static int
1371v9fs_vfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t rdev)
1372{
1373 struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dir);
1374 int retval;
1375 char name[2 + U32_MAX_DIGITS + 1 + U32_MAX_DIGITS + 1];
1376 u32 perm;
1377
1378 p9_debug(P9_DEBUG_VFS, " %lu,%pd mode: %hx MAJOR: %u MINOR: %u\n",
1379 dir->i_ino, dentry, mode,
1380 MAJOR(rdev), MINOR(rdev));
1381
1382 /* build extension */
1383 if (S_ISBLK(mode))
1384 sprintf(name, "b %u %u", MAJOR(rdev), MINOR(rdev));
1385 else if (S_ISCHR(mode))
1386 sprintf(name, "c %u %u", MAJOR(rdev), MINOR(rdev));
1387 else
1388 *name = 0;
1389
1390 perm = unixmode2p9mode(v9ses, mode);
1391 retval = v9fs_vfs_mkspecial(dir, dentry, perm, name);
1392
1393 return retval;
1394}
1395
1396int v9fs_refresh_inode(struct p9_fid *fid, struct inode *inode)
1397{
1398 int umode;
1399 dev_t rdev;
1400 struct p9_wstat *st;
1401 struct v9fs_session_info *v9ses;
1402 unsigned int flags;
1403
1404 v9ses = v9fs_inode2v9ses(inode);
1405 st = p9_client_stat(fid);
1406 if (IS_ERR(st))
1407 return PTR_ERR(st);
1408 /*
1409 * Don't update inode if the file type is different
1410 */
1411 umode = p9mode2unixmode(v9ses, st, &rdev);
1412 if ((inode->i_mode & S_IFMT) != (umode & S_IFMT))
1413 goto out;
1414
1415 /*
1416 * We don't want to refresh inode->i_size,
1417 * because we may have cached data
1418 */
1419 flags = (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) ?
1420 V9FS_STAT2INODE_KEEP_ISIZE : 0;
1421 v9fs_stat2inode(st, inode, inode->i_sb, flags);
1422out:
1423 p9stat_free(st);
1424 kfree(st);
1425 return 0;
1426}
1427
1428static const struct inode_operations v9fs_dir_inode_operations_dotu = {
1429 .create = v9fs_vfs_create,
1430 .lookup = v9fs_vfs_lookup,
1431 .atomic_open = v9fs_vfs_atomic_open,
1432 .symlink = v9fs_vfs_symlink,
1433 .link = v9fs_vfs_link,
1434 .unlink = v9fs_vfs_unlink,
1435 .mkdir = v9fs_vfs_mkdir,
1436 .rmdir = v9fs_vfs_rmdir,
1437 .mknod = v9fs_vfs_mknod,
1438 .rename = v9fs_vfs_rename,
1439 .getattr = v9fs_vfs_getattr,
1440 .setattr = v9fs_vfs_setattr,
1441};
1442
1443static const struct inode_operations v9fs_dir_inode_operations = {
1444 .create = v9fs_vfs_create,
1445 .lookup = v9fs_vfs_lookup,
1446 .atomic_open = v9fs_vfs_atomic_open,
1447 .unlink = v9fs_vfs_unlink,
1448 .mkdir = v9fs_vfs_mkdir,
1449 .rmdir = v9fs_vfs_rmdir,
1450 .mknod = v9fs_vfs_mknod,
1451 .rename = v9fs_vfs_rename,
1452 .getattr = v9fs_vfs_getattr,
1453 .setattr = v9fs_vfs_setattr,
1454};
1455
1456static const struct inode_operations v9fs_file_inode_operations = {
1457 .getattr = v9fs_vfs_getattr,
1458 .setattr = v9fs_vfs_setattr,
1459};
1460
1461static const struct inode_operations v9fs_symlink_inode_operations = {
1462 .get_link = v9fs_vfs_get_link,
1463 .getattr = v9fs_vfs_getattr,
1464 .setattr = v9fs_vfs_setattr,
1465};
1466