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
unixmode2p9mode(struct v9fs_session_info * v9ses,umode_t mode)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 */
p9mode2perm(struct v9fs_session_info * v9ses,struct p9_wstat * stat)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 & 0777; /* S_IRWXUGO */
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 */
p9mode2unixmode(struct v9fs_session_info * v9ses,struct p9_wstat * stat,dev_t * rdev)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
v9fs_uflags2omode(int uflags,int extended)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 (uflags & O_TRUNC)
182 ret |= P9_OTRUNC;
183
184 if (extended) {
185 if (uflags & O_EXCL)
186 ret |= P9_OEXCL;
187
188 if (uflags & O_APPEND)
189 ret |= P9_OAPPEND;
190 }
191
192 return ret;
193 }
194
195 /**
196 * v9fs_blank_wstat - helper function to setup a 9P stat structure
197 * @wstat: structure to initialize
198 *
199 */
200
201 void
v9fs_blank_wstat(struct p9_wstat * wstat)202 v9fs_blank_wstat(struct p9_wstat *wstat)
203 {
204 wstat->type = ~0;
205 wstat->dev = ~0;
206 wstat->qid.type = ~0;
207 wstat->qid.version = ~0;
208 *((long long *)&wstat->qid.path) = ~0;
209 wstat->mode = ~0;
210 wstat->atime = ~0;
211 wstat->mtime = ~0;
212 wstat->length = ~0;
213 wstat->name = NULL;
214 wstat->uid = NULL;
215 wstat->gid = NULL;
216 wstat->muid = NULL;
217 wstat->n_uid = INVALID_UID;
218 wstat->n_gid = INVALID_GID;
219 wstat->n_muid = INVALID_UID;
220 wstat->extension = NULL;
221 }
222
223 /**
224 * v9fs_alloc_inode - helper function to allocate an inode
225 * @sb: The superblock to allocate the inode from
226 */
v9fs_alloc_inode(struct super_block * sb)227 struct inode *v9fs_alloc_inode(struct super_block *sb)
228 {
229 struct v9fs_inode *v9inode;
230
231 v9inode = alloc_inode_sb(sb, v9fs_inode_cache, GFP_KERNEL);
232 if (!v9inode)
233 return 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
v9fs_free_inode(struct inode * inode)244 void 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 */
v9fs_set_netfs_context(struct inode * inode)252 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, true);
256 }
257
v9fs_init_inode(struct v9fs_session_info * v9ses,struct inode * inode,umode_t mode,dev_t rdev)258 int 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(&nop_mnt_idmap, inode, NULL, mode);
264 inode->i_blocks = 0;
265 inode->i_rdev = rdev;
266 simple_inode_init_ts(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 inode->i_fop = &v9fs_file_operations_dotl;
291 } else {
292 inode->i_op = &v9fs_file_inode_operations;
293 inode->i_fop = &v9fs_file_operations;
294 }
295
296 break;
297 case S_IFLNK:
298 if (!v9fs_proto_dotu(v9ses) && !v9fs_proto_dotl(v9ses)) {
299 p9_debug(P9_DEBUG_ERROR,
300 "extended modes used with legacy protocol\n");
301 err = -EINVAL;
302 goto error;
303 }
304
305 if (v9fs_proto_dotl(v9ses)) {
306 inode->i_op = &v9fs_symlink_inode_operations_dotl;
307 inode_nohighmem(inode);
308 } else {
309 inode->i_op = &v9fs_symlink_inode_operations;
310 }
311
312 break;
313 case S_IFDIR:
314 inc_nlink(inode);
315 if (v9fs_proto_dotl(v9ses))
316 inode->i_op = &v9fs_dir_inode_operations_dotl;
317 else if (v9fs_proto_dotu(v9ses))
318 inode->i_op = &v9fs_dir_inode_operations_dotu;
319 else
320 inode->i_op = &v9fs_dir_inode_operations;
321
322 if (v9fs_proto_dotl(v9ses))
323 inode->i_fop = &v9fs_dir_operations_dotl;
324 else
325 inode->i_fop = &v9fs_dir_operations;
326
327 break;
328 default:
329 p9_debug(P9_DEBUG_ERROR, "BAD mode 0x%hx S_IFMT 0x%x\n",
330 mode, mode & S_IFMT);
331 err = -EINVAL;
332 goto error;
333 }
334 error:
335 return err;
336
337 }
338
339 /**
340 * v9fs_evict_inode - Remove an inode from the inode cache
341 * @inode: inode to release
342 *
343 */
v9fs_evict_inode(struct inode * inode)344 void v9fs_evict_inode(struct inode *inode)
345 {
346 struct v9fs_inode __maybe_unused *v9inode = V9FS_I(inode);
347 __le32 __maybe_unused version;
348
349 if (!is_bad_inode(inode)) {
350 netfs_wait_for_outstanding_io(inode);
351 truncate_inode_pages_final(&inode->i_data);
352
353 version = cpu_to_le32(v9inode->qid.version);
354 netfs_clear_inode_writeback(inode, &version);
355
356 clear_inode(inode);
357 filemap_fdatawrite(&inode->i_data);
358
359 #ifdef CONFIG_9P_FSCACHE
360 if (v9fs_inode_cookie(v9inode))
361 fscache_relinquish_cookie(v9fs_inode_cookie(v9inode), false);
362 #endif
363 } else
364 clear_inode(inode);
365 }
366
v9fs_test_inode(struct inode * inode,void * data)367 static int v9fs_test_inode(struct inode *inode, void *data)
368 {
369 int umode;
370 dev_t rdev;
371 struct v9fs_inode *v9inode = V9FS_I(inode);
372 struct p9_wstat *st = (struct p9_wstat *)data;
373 struct v9fs_session_info *v9ses = v9fs_inode2v9ses(inode);
374
375 umode = p9mode2unixmode(v9ses, st, &rdev);
376 /* don't match inode of different type */
377 if (inode_wrong_type(inode, umode))
378 return 0;
379
380 /* compare qid details */
381 if (memcmp(&v9inode->qid.version,
382 &st->qid.version, sizeof(v9inode->qid.version)))
383 return 0;
384
385 if (v9inode->qid.type != st->qid.type)
386 return 0;
387
388 if (v9inode->qid.path != st->qid.path)
389 return 0;
390 return 1;
391 }
392
v9fs_test_new_inode(struct inode * inode,void * data)393 static int v9fs_test_new_inode(struct inode *inode, void *data)
394 {
395 return 0;
396 }
397
v9fs_set_inode(struct inode * inode,void * data)398 static int v9fs_set_inode(struct inode *inode, void *data)
399 {
400 struct v9fs_inode *v9inode = V9FS_I(inode);
401 struct p9_wstat *st = (struct p9_wstat *)data;
402
403 memcpy(&v9inode->qid, &st->qid, sizeof(st->qid));
404 return 0;
405 }
406
v9fs_qid_iget(struct super_block * sb,struct p9_qid * qid,struct p9_wstat * st,int new)407 static struct inode *v9fs_qid_iget(struct super_block *sb,
408 struct p9_qid *qid,
409 struct p9_wstat *st,
410 int new)
411 {
412 dev_t rdev;
413 int retval;
414 umode_t umode;
415 struct inode *inode;
416 struct v9fs_session_info *v9ses = sb->s_fs_info;
417 int (*test)(struct inode *inode, void *data);
418
419 if (new)
420 test = v9fs_test_new_inode;
421 else
422 test = v9fs_test_inode;
423
424 inode = iget5_locked(sb, QID2INO(qid), test, v9fs_set_inode, st);
425 if (!inode)
426 return ERR_PTR(-ENOMEM);
427 if (!(inode_state_read_once(inode) & I_NEW))
428 return inode;
429 /*
430 * initialize the inode with the stat info
431 * FIXME!! we may need support for stale inodes
432 * later.
433 */
434 inode->i_ino = QID2INO(qid);
435 umode = p9mode2unixmode(v9ses, st, &rdev);
436 retval = v9fs_init_inode(v9ses, inode, umode, rdev);
437 if (retval)
438 goto error;
439
440 v9fs_stat2inode(st, inode, sb, 0);
441 v9fs_set_netfs_context(inode);
442 v9fs_cache_inode_get_cookie(inode);
443 unlock_new_inode(inode);
444 return inode;
445 error:
446 iget_failed(inode);
447 return ERR_PTR(retval);
448
449 }
450
451 struct inode *
v9fs_inode_from_fid(struct v9fs_session_info * v9ses,struct p9_fid * fid,struct super_block * sb,int new)452 v9fs_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid,
453 struct super_block *sb, int new)
454 {
455 struct p9_wstat *st;
456 struct inode *inode = NULL;
457
458 st = p9_client_stat(fid);
459 if (IS_ERR(st))
460 return ERR_CAST(st);
461
462 inode = v9fs_qid_iget(sb, &st->qid, st, new);
463 p9stat_free(st);
464 kfree(st);
465 return inode;
466 }
467
468 /**
469 * v9fs_at_to_dotl_flags- convert Linux specific AT flags to
470 * plan 9 AT flag.
471 * @flags: flags to convert
472 */
v9fs_at_to_dotl_flags(int flags)473 static int v9fs_at_to_dotl_flags(int flags)
474 {
475 int rflags = 0;
476
477 if (flags & AT_REMOVEDIR)
478 rflags |= P9_DOTL_AT_REMOVEDIR;
479
480 return rflags;
481 }
482
483 /**
484 * v9fs_dec_count - helper functon to drop i_nlink.
485 *
486 * If a directory had nlink <= 2 (including . and ..), then we should not drop
487 * the link count, which indicates the underlying exported fs doesn't maintain
488 * nlink accurately. e.g.
489 * - overlayfs sets nlink to 1 for merged dir
490 * - ext4 (with dir_nlink feature enabled) sets nlink to 1 if a dir has more
491 * than EXT4_LINK_MAX (65000) links.
492 *
493 * In cacheless mode the server is the source of truth for nlink and the
494 * inode is going away immediately, so locally adjusting i_nlink buys
495 * nothing and races with concurrent metadata fetches that may already
496 * have observed the post-unlink value (nlink == 0).
497 *
498 * @inode: inode whose nlink is being dropped
499 */
v9fs_dec_count(struct inode * inode)500 static void v9fs_dec_count(struct inode *inode)
501 {
502 struct v9fs_session_info *v9ses = v9fs_inode2v9ses(inode);
503
504 if (!(v9ses->cache & (CACHE_META | CACHE_LOOSE)))
505 return;
506 if (!S_ISDIR(inode->i_mode) || inode->i_nlink > 2)
507 drop_nlink(inode);
508 }
509
510 /**
511 * v9fs_remove - helper function to remove files and directories
512 * @dir: directory inode that is being deleted
513 * @dentry: dentry that is being deleted
514 * @flags: removing a directory
515 *
516 */
517
v9fs_remove(struct inode * dir,struct dentry * dentry,int flags)518 static int v9fs_remove(struct inode *dir, struct dentry *dentry, int flags)
519 {
520 struct inode *inode;
521 int retval = -EOPNOTSUPP;
522 struct p9_fid *v9fid, *dfid;
523 struct v9fs_session_info *v9ses;
524
525 p9_debug(P9_DEBUG_VFS, "inode: %p dentry: %p rmdir: %x\n",
526 dir, dentry, flags);
527
528 v9ses = v9fs_inode2v9ses(dir);
529 inode = d_inode(dentry);
530 dfid = v9fs_parent_fid(dentry);
531 if (IS_ERR(dfid)) {
532 retval = PTR_ERR(dfid);
533 p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", retval);
534 return retval;
535 }
536 if (v9fs_proto_dotl(v9ses))
537 retval = p9_client_unlinkat(dfid, dentry->d_name.name,
538 v9fs_at_to_dotl_flags(flags));
539 p9_fid_put(dfid);
540 if (retval == -EOPNOTSUPP) {
541 /* Try the one based on path */
542 v9fid = v9fs_fid_clone(dentry);
543 if (IS_ERR(v9fid))
544 return PTR_ERR(v9fid);
545 retval = p9_client_remove(v9fid);
546 }
547 if (!retval) {
548 /*
549 * directories on unlink should have zero
550 * link count
551 */
552 if (flags & AT_REMOVEDIR) {
553 clear_nlink(inode);
554 v9fs_dec_count(dir);
555 } else
556 v9fs_dec_count(inode);
557
558 v9fs_invalidate_inode_attr(inode);
559 v9fs_invalidate_inode_attr(dir);
560
561 /* invalidate all fids associated with dentry */
562 /* NOTE: This will not include open fids */
563 v9fs_dentry_fid_remove(dentry);
564 }
565 return retval;
566 }
567
568 /**
569 * v9fs_create - Create a file
570 * @v9ses: session information
571 * @dir: directory that dentry is being created in
572 * @dentry: dentry that is being created
573 * @extension: 9p2000.u extension string to support devices, etc.
574 * @perm: create permissions
575 * @mode: open mode
576 *
577 */
578 static struct p9_fid *
v9fs_create(struct v9fs_session_info * v9ses,struct inode * dir,struct dentry * dentry,char * extension,u32 perm,u8 mode)579 v9fs_create(struct v9fs_session_info *v9ses, struct inode *dir,
580 struct dentry *dentry, char *extension, u32 perm, u8 mode)
581 {
582 int err;
583 const unsigned char *name;
584 struct p9_fid *dfid, *ofid = NULL, *fid = NULL;
585 struct inode *inode;
586
587 p9_debug(P9_DEBUG_VFS, "name %pd\n", dentry);
588
589 name = dentry->d_name.name;
590 dfid = v9fs_parent_fid(dentry);
591 if (IS_ERR(dfid)) {
592 err = PTR_ERR(dfid);
593 p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
594 return ERR_PTR(err);
595 }
596
597 /* clone a fid to use for creation */
598 ofid = clone_fid(dfid);
599 if (IS_ERR(ofid)) {
600 err = PTR_ERR(ofid);
601 p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
602 goto error;
603 }
604
605 err = p9_client_fcreate(ofid, name, perm, mode, extension);
606 if (err < 0) {
607 p9_debug(P9_DEBUG_VFS, "p9_client_fcreate failed %d\n", err);
608 goto error;
609 }
610
611 if (!(perm & P9_DMLINK)) {
612 /* now walk from the parent so we can get unopened fid */
613 fid = p9_client_walk(dfid, 1, &name, 1);
614 if (IS_ERR(fid)) {
615 err = PTR_ERR(fid);
616 p9_debug(P9_DEBUG_VFS,
617 "p9_client_walk failed %d\n", err);
618 goto error;
619 }
620 /*
621 * instantiate inode and assign the unopened fid to the dentry
622 */
623 inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
624 if (IS_ERR(inode)) {
625 err = PTR_ERR(inode);
626 p9_debug(P9_DEBUG_VFS,
627 "inode creation failed %d\n", err);
628 goto error;
629 }
630 v9fs_fid_add(dentry, &fid);
631 d_instantiate(dentry, inode);
632 }
633 p9_fid_put(dfid);
634 return ofid;
635 error:
636 p9_fid_put(dfid);
637 p9_fid_put(ofid);
638 p9_fid_put(fid);
639 return ERR_PTR(err);
640 }
641
642 /**
643 * v9fs_vfs_create - VFS hook to create a regular file
644 * @idmap: idmap of the mount
645 * @dir: The parent directory
646 * @dentry: The name of file to be created
647 * @mode: The UNIX file mode to set
648 *
649 * open(.., O_CREAT) is handled in v9fs_vfs_atomic_open(). This is only called
650 * for mknod(2).
651 *
652 */
653
654 static int
v9fs_vfs_create(const struct mnt_idmap * idmap,struct inode * dir,struct dentry * dentry,umode_t mode)655 v9fs_vfs_create(const struct mnt_idmap *idmap, struct inode *dir,
656 struct dentry *dentry, umode_t mode)
657 {
658 struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dir);
659 u32 perm = unixmode2p9mode(v9ses, mode);
660 struct p9_fid *fid;
661
662 /* P9_OEXCL? */
663 fid = v9fs_create(v9ses, dir, dentry, NULL, perm, P9_ORDWR);
664 if (IS_ERR(fid))
665 return PTR_ERR(fid);
666
667 v9fs_invalidate_inode_attr(dir);
668 p9_fid_put(fid);
669
670 return 0;
671 }
672
673 /**
674 * v9fs_vfs_mkdir - VFS mkdir hook to create a directory
675 * @idmap: idmap of the mount
676 * @dir: inode that is being unlinked
677 * @dentry: dentry that is being unlinked
678 * @mode: mode for new directory
679 *
680 */
681
v9fs_vfs_mkdir(const struct mnt_idmap * idmap,struct inode * dir,struct dentry * dentry,umode_t mode)682 static struct dentry *v9fs_vfs_mkdir(const struct mnt_idmap *idmap, struct inode *dir,
683 struct dentry *dentry, umode_t mode)
684 {
685 u32 perm;
686 struct p9_fid *fid;
687 struct v9fs_session_info *v9ses;
688
689 p9_debug(P9_DEBUG_VFS, "name %pd\n", dentry);
690 v9ses = v9fs_inode2v9ses(dir);
691 perm = unixmode2p9mode(v9ses, mode);
692 fid = v9fs_create(v9ses, dir, dentry, NULL, perm, P9_OREAD);
693 if (IS_ERR(fid))
694 return ERR_CAST(fid);
695 inc_nlink(dir);
696 v9fs_invalidate_inode_attr(dir);
697 p9_fid_put(fid);
698 return NULL;
699 }
700
701 /**
702 * v9fs_vfs_lookup - VFS lookup hook to "walk" to a new inode
703 * @dir: inode that is being walked from
704 * @dentry: dentry that is being walked to?
705 * @flags: lookup flags (unused)
706 *
707 */
708
v9fs_vfs_lookup(struct inode * dir,struct dentry * dentry,unsigned int flags)709 struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
710 unsigned int flags)
711 {
712 struct dentry *res;
713 struct v9fs_session_info *v9ses;
714 struct p9_fid *dfid, *fid;
715 struct inode *inode;
716 const unsigned char *name;
717
718 p9_debug(P9_DEBUG_VFS, "dir: %p dentry: (%pd) %p flags: %x\n",
719 dir, dentry, dentry, flags);
720
721 if (dentry->d_name.len > NAME_MAX)
722 return ERR_PTR(-ENAMETOOLONG);
723
724 v9ses = v9fs_inode2v9ses(dir);
725 /* We can walk d_parent because we hold the dir->i_mutex */
726 dfid = v9fs_parent_fid(dentry);
727 if (IS_ERR(dfid))
728 return ERR_CAST(dfid);
729
730 /*
731 * Make sure we don't use a wrong inode due to parallel
732 * unlink. For cached mode create calls request for new
733 * inode. But with cache disabled, lookup should do this.
734 */
735 name = dentry->d_name.name;
736 fid = p9_client_walk(dfid, 1, &name, 1);
737 p9_fid_put(dfid);
738 if (fid == ERR_PTR(-ENOENT)) {
739 inode = NULL;
740 v9fs_ndentry_refresh_timeout(dentry);
741 } else if (IS_ERR(fid)) {
742 inode = ERR_CAST(fid);
743 } else if (v9ses->cache & (CACHE_META|CACHE_LOOSE)) {
744 inode = v9fs_get_inode_from_fid(v9ses, fid, dir->i_sb);
745 } else {
746 inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
747 }
748 /*
749 * If we had a rename on the server and a parallel lookup
750 * for the new name, then make sure we instantiate with
751 * the new name. ie look up for a/b, while on server somebody
752 * moved b under k and client parallely did a lookup for
753 * k/b.
754 */
755 res = d_splice_alias(inode, dentry);
756 if (!IS_ERR(fid)) {
757 if (!res)
758 v9fs_fid_add(dentry, &fid);
759 else if (!IS_ERR(res))
760 v9fs_fid_add(res, &fid);
761 else
762 p9_fid_put(fid);
763 }
764 return res;
765 }
766
767 static int
v9fs_vfs_atomic_open(struct inode * dir,struct dentry * dentry,struct file * file,unsigned int flags,umode_t mode)768 v9fs_vfs_atomic_open(struct inode *dir, struct dentry *dentry,
769 struct file *file, unsigned int flags, umode_t mode)
770 {
771 int err;
772 u32 perm;
773 struct v9fs_inode __maybe_unused *v9inode;
774 struct v9fs_session_info *v9ses;
775 struct p9_fid *fid;
776 struct inode *inode;
777 int p9_omode;
778
779 if (d_in_lookup(dentry)) {
780 struct dentry *res = v9fs_vfs_lookup(dir, dentry, 0);
781 if (res || d_really_is_positive(dentry))
782 return finish_no_open(file, res);
783 }
784
785 /* Only creates */
786 if (!(flags & O_CREAT))
787 return finish_no_open(file, NULL);
788
789 v9ses = v9fs_inode2v9ses(dir);
790 perm = unixmode2p9mode(v9ses, mode);
791 p9_omode = v9fs_uflags2omode(flags, v9fs_proto_dotu(v9ses));
792
793 if ((v9ses->cache & CACHE_WRITEBACK) && (p9_omode & P9_OWRITE)) {
794 p9_omode = (p9_omode & ~(P9_OWRITE | P9_OAPPEND)) | P9_ORDWR;
795 p9_debug(P9_DEBUG_CACHE,
796 "write-only file with writeback enabled, creating w/ O_RDWR\n");
797 }
798 fid = v9fs_create(v9ses, dir, dentry, NULL, perm, p9_omode);
799 if (IS_ERR(fid))
800 return PTR_ERR(fid);
801
802 v9fs_invalidate_inode_attr(dir);
803 inode = d_inode(dentry);
804 v9inode = V9FS_I(inode);
805 err = finish_open(file, dentry, generic_file_open);
806 if (unlikely(err)) {
807 p9_fid_put(fid);
808 return err;
809 }
810
811 file->private_data = fid;
812 #ifdef CONFIG_9P_FSCACHE
813 if (v9ses->cache & CACHE_FSCACHE)
814 fscache_use_cookie(v9fs_inode_cookie(v9inode),
815 file->f_mode & FMODE_WRITE);
816 #endif
817
818 v9fs_fid_add_modes(fid, v9ses->flags, v9ses->cache, file->f_flags);
819 v9fs_open_fid_add(inode, &fid);
820
821 file->f_mode |= FMODE_CREATED;
822 return 0;
823 }
824
825 /**
826 * v9fs_vfs_unlink - VFS unlink hook to delete an inode
827 * @i: inode that is being unlinked
828 * @d: dentry that is being unlinked
829 *
830 */
831
v9fs_vfs_unlink(struct inode * i,struct dentry * d)832 int v9fs_vfs_unlink(struct inode *i, struct dentry *d)
833 {
834 return v9fs_remove(i, d, 0);
835 }
836
837 /**
838 * v9fs_vfs_rmdir - VFS unlink hook to delete a directory
839 * @i: inode that is being unlinked
840 * @d: dentry that is being unlinked
841 *
842 */
843
v9fs_vfs_rmdir(struct inode * i,struct dentry * d)844 int v9fs_vfs_rmdir(struct inode *i, struct dentry *d)
845 {
846 return v9fs_remove(i, d, AT_REMOVEDIR);
847 }
848
849 /**
850 * v9fs_vfs_rename - VFS hook to rename an inode
851 * @idmap: The idmap of the mount
852 * @old_dir: old dir inode
853 * @old_dentry: old dentry
854 * @new_dir: new dir inode
855 * @new_dentry: new dentry
856 * @flags: RENAME_* flags
857 *
858 */
859
860 int
v9fs_vfs_rename(const struct mnt_idmap * idmap,struct inode * old_dir,struct dentry * old_dentry,struct inode * new_dir,struct dentry * new_dentry,unsigned int flags)861 v9fs_vfs_rename(const struct mnt_idmap *idmap, struct inode *old_dir,
862 struct dentry *old_dentry, struct inode *new_dir,
863 struct dentry *new_dentry, unsigned int flags)
864 {
865 int retval;
866 struct inode *old_inode;
867 struct inode *new_inode;
868 struct v9fs_session_info *v9ses;
869 struct p9_fid *oldfid = NULL, *dfid = NULL;
870 struct p9_fid *olddirfid = NULL;
871 struct p9_fid *newdirfid = NULL;
872 struct p9_wstat wstat;
873
874 if (flags)
875 return -EINVAL;
876
877 p9_debug(P9_DEBUG_VFS, "\n");
878 old_inode = d_inode(old_dentry);
879 new_inode = d_inode(new_dentry);
880 v9ses = v9fs_inode2v9ses(old_inode);
881 oldfid = v9fs_fid_lookup(old_dentry);
882 if (IS_ERR(oldfid))
883 return PTR_ERR(oldfid);
884
885 dfid = v9fs_parent_fid(old_dentry);
886 olddirfid = clone_fid(dfid);
887 p9_fid_put(dfid);
888 dfid = NULL;
889
890 if (IS_ERR(olddirfid)) {
891 retval = PTR_ERR(olddirfid);
892 goto error;
893 }
894
895 dfid = v9fs_parent_fid(new_dentry);
896 newdirfid = clone_fid(dfid);
897 p9_fid_put(dfid);
898 dfid = NULL;
899
900 if (IS_ERR(newdirfid)) {
901 retval = PTR_ERR(newdirfid);
902 goto error;
903 }
904
905 down_write(&v9ses->rename_sem);
906 if (v9fs_proto_dotl(v9ses)) {
907 retval = p9_client_renameat(olddirfid, old_dentry->d_name.name,
908 newdirfid, new_dentry->d_name.name);
909 if (retval == -EOPNOTSUPP)
910 retval = p9_client_rename(oldfid, newdirfid,
911 new_dentry->d_name.name);
912 if (retval != -EOPNOTSUPP)
913 goto error_locked;
914 }
915 if (old_dentry->d_parent != new_dentry->d_parent) {
916 /*
917 * 9P .u can only handle file rename in the same directory
918 */
919
920 p9_debug(P9_DEBUG_ERROR, "old dir and new dir are different\n");
921 retval = -EXDEV;
922 goto error_locked;
923 }
924 v9fs_blank_wstat(&wstat);
925 wstat.muid = v9ses->uname;
926 wstat.name = new_dentry->d_name.name;
927 retval = p9_client_wstat(oldfid, &wstat);
928
929 error_locked:
930 if (!retval) {
931 if (new_inode) {
932 if (S_ISDIR(new_inode->i_mode))
933 clear_nlink(new_inode);
934 else
935 v9fs_dec_count(new_inode);
936 }
937 if (S_ISDIR(old_inode->i_mode)) {
938 if (!new_inode)
939 inc_nlink(new_dir);
940 v9fs_dec_count(old_dir);
941 }
942 v9fs_invalidate_inode_attr(old_inode);
943 v9fs_invalidate_inode_attr(old_dir);
944 v9fs_invalidate_inode_attr(new_dir);
945
946 /* successful rename */
947 d_move(old_dentry, new_dentry);
948 }
949 up_write(&v9ses->rename_sem);
950
951 error:
952 p9_fid_put(newdirfid);
953 p9_fid_put(olddirfid);
954 p9_fid_put(oldfid);
955 return retval;
956 }
957
958 /**
959 * v9fs_vfs_getattr - retrieve file metadata
960 * @idmap: idmap of the mount
961 * @path: Object to query
962 * @stat: metadata structure to populate
963 * @request_mask: Mask of STATX_xxx flags indicating the caller's interests
964 * @flags: AT_STATX_xxx setting
965 *
966 */
967
968 static int
v9fs_vfs_getattr(const struct mnt_idmap * idmap,const struct path * path,struct kstat * stat,u32 request_mask,unsigned int flags)969 v9fs_vfs_getattr(const struct mnt_idmap *idmap, const struct path *path,
970 struct kstat *stat, u32 request_mask, unsigned int flags)
971 {
972 struct dentry *dentry = path->dentry;
973 struct inode *inode = d_inode(dentry);
974 struct v9fs_session_info *v9ses;
975 struct p9_fid *fid;
976 struct p9_wstat *st;
977
978 p9_debug(P9_DEBUG_VFS, "dentry: %p\n", dentry);
979 v9ses = v9fs_dentry2v9ses(dentry);
980 if (v9ses->cache & (CACHE_META|CACHE_LOOSE)) {
981 generic_fillattr(&nop_mnt_idmap, request_mask, inode, stat);
982 return 0;
983 } else if (v9ses->cache & CACHE_WRITEBACK) {
984 if (S_ISREG(inode->i_mode)) {
985 int retval = filemap_fdatawrite(inode->i_mapping);
986
987 if (retval)
988 p9_debug(P9_DEBUG_ERROR,
989 "flushing writeback during getattr returned %d\n", retval);
990 }
991 }
992 fid = v9fs_fid_lookup(dentry);
993 if (IS_ERR(fid))
994 return PTR_ERR(fid);
995
996 st = p9_client_stat(fid);
997 p9_fid_put(fid);
998 if (IS_ERR(st))
999 return PTR_ERR(st);
1000
1001 v9fs_stat2inode(st, d_inode(dentry), dentry->d_sb, 0);
1002 generic_fillattr(&nop_mnt_idmap, request_mask, d_inode(dentry), stat);
1003
1004 p9stat_free(st);
1005 kfree(st);
1006 return 0;
1007 }
1008
1009 /**
1010 * v9fs_vfs_setattr - set file metadata
1011 * @idmap: idmap of the mount
1012 * @dentry: file whose metadata to set
1013 * @iattr: metadata assignment structure
1014 *
1015 */
1016
v9fs_vfs_setattr(const struct mnt_idmap * idmap,struct dentry * dentry,struct iattr * iattr)1017 static int v9fs_vfs_setattr(const struct mnt_idmap *idmap,
1018 struct dentry *dentry, struct iattr *iattr)
1019 {
1020 int retval, use_dentry = 0;
1021 struct inode *inode = d_inode(dentry);
1022 struct v9fs_session_info *v9ses;
1023 struct p9_fid *fid = NULL;
1024 struct p9_wstat wstat;
1025 #ifdef CONFIG_9P_FSCACHE
1026 uoff_t old_size = i_size_read(inode);
1027 #endif
1028
1029 p9_debug(P9_DEBUG_VFS, "\n");
1030 retval = setattr_prepare(&nop_mnt_idmap, dentry, iattr);
1031 if (retval)
1032 return retval;
1033
1034 v9ses = v9fs_dentry2v9ses(dentry);
1035 if (iattr->ia_valid & ATTR_FILE) {
1036 fid = iattr->ia_file->private_data;
1037 WARN_ON(!fid);
1038 }
1039 if (!fid) {
1040 fid = v9fs_fid_lookup(dentry);
1041 use_dentry = 1;
1042 }
1043 if (IS_ERR(fid))
1044 return PTR_ERR(fid);
1045
1046 v9fs_blank_wstat(&wstat);
1047 if (iattr->ia_valid & ATTR_MODE)
1048 wstat.mode = unixmode2p9mode(v9ses, iattr->ia_mode);
1049
1050 if (iattr->ia_valid & ATTR_MTIME)
1051 wstat.mtime = iattr->ia_mtime.tv_sec;
1052
1053 if (iattr->ia_valid & ATTR_ATIME)
1054 wstat.atime = iattr->ia_atime.tv_sec;
1055
1056 if (iattr->ia_valid & ATTR_SIZE)
1057 wstat.length = iattr->ia_size;
1058
1059 if (v9fs_proto_dotu(v9ses)) {
1060 if (iattr->ia_valid & ATTR_UID)
1061 wstat.n_uid = iattr->ia_uid;
1062
1063 if (iattr->ia_valid & ATTR_GID)
1064 wstat.n_gid = iattr->ia_gid;
1065 }
1066
1067 /* Write all dirty data */
1068 if (d_is_reg(dentry)) {
1069 retval = filemap_fdatawrite(inode->i_mapping);
1070 if (retval)
1071 p9_debug(P9_DEBUG_ERROR,
1072 "flushing writeback during setattr returned %d\n", retval);
1073 }
1074
1075 retval = p9_client_wstat(fid, &wstat);
1076
1077 if (use_dentry)
1078 p9_fid_put(fid);
1079
1080 if (retval < 0)
1081 return retval;
1082
1083 if ((iattr->ia_valid & ATTR_SIZE) &&
1084 iattr->ia_size != i_size_read(inode)) {
1085 truncate_setsize(inode, iattr->ia_size);
1086 netfs_resize_file(netfs_inode(inode), iattr->ia_size, true);
1087
1088 #ifdef CONFIG_9P_FSCACHE
1089 if (v9ses->cache & CACHE_FSCACHE) {
1090 struct v9fs_inode *v9inode = V9FS_I(inode);
1091
1092 fscache_resize_cookie(v9fs_inode_cookie(v9inode),
1093 iattr->ia_size, iattr->ia_size < old_size);
1094 }
1095 #endif
1096 }
1097
1098 v9fs_invalidate_inode_attr(inode);
1099
1100 setattr_copy(&nop_mnt_idmap, inode, iattr);
1101 mark_inode_dirty(inode);
1102 return 0;
1103 }
1104
1105 /**
1106 * v9fs_stat2inode - populate an inode structure with mistat info
1107 * @stat: Plan 9 metadata (mistat) structure
1108 * @inode: inode to populate
1109 * @sb: superblock of filesystem
1110 * @flags: control flags (e.g. V9FS_STAT2INODE_KEEP_ISIZE)
1111 *
1112 */
1113
1114 void
v9fs_stat2inode(struct p9_wstat * stat,struct inode * inode,struct super_block * sb,unsigned int flags)1115 v9fs_stat2inode(struct p9_wstat *stat, struct inode *inode,
1116 struct super_block *sb, unsigned int flags)
1117 {
1118 umode_t mode;
1119 struct v9fs_session_info *v9ses = sb->s_fs_info;
1120 struct v9fs_inode *v9inode = V9FS_I(inode);
1121
1122 inode_set_atime(inode, stat->atime, 0);
1123 inode_set_mtime(inode, stat->mtime, 0);
1124 inode_set_ctime(inode, stat->mtime, 0);
1125
1126 inode->i_uid = v9ses->dfltuid;
1127 inode->i_gid = v9ses->dfltgid;
1128
1129 if (v9fs_proto_dotu(v9ses)) {
1130 inode->i_uid = stat->n_uid;
1131 inode->i_gid = stat->n_gid;
1132 }
1133 if ((S_ISREG(inode->i_mode)) || (S_ISDIR(inode->i_mode))) {
1134 if (v9fs_proto_dotu(v9ses)) {
1135 unsigned int i_nlink;
1136 /*
1137 * Hadlink support got added later to the .u extension.
1138 * So there can be a server out there that doesn't
1139 * support this even with .u extension. That would
1140 * just leave us with stat->extension being an empty
1141 * string, though.
1142 */
1143 /* HARDLINKCOUNT %u */
1144 if (sscanf(stat->extension,
1145 " HARDLINKCOUNT %u", &i_nlink) == 1)
1146 set_nlink(inode, i_nlink);
1147 }
1148 }
1149 mode = p9mode2perm(v9ses, stat);
1150 mode |= inode->i_mode & ~S_IALLUGO;
1151 inode->i_mode = mode;
1152
1153 spin_lock(&inode->i_lock);
1154 netfs_write_remote_i_size(inode, stat->length);
1155 if (!(flags & V9FS_STAT2INODE_KEEP_ISIZE))
1156 i_size_write(inode, stat->length);
1157 /* not real number of blocks, but 512 byte ones ... */
1158 inode->i_blocks = (stat->length + 512 - 1) >> 9;
1159 spin_unlock(&inode->i_lock);
1160 v9inode->cache_validity &= ~V9FS_INO_INVALID_ATTR;
1161 }
1162
1163 /**
1164 * v9fs_vfs_get_link - follow a symlink path
1165 * @dentry: dentry for symlink
1166 * @inode: inode for symlink
1167 * @done: delayed call for when we are done with the return value
1168 */
1169
v9fs_vfs_get_link(struct dentry * dentry,struct inode * inode,struct delayed_call * done)1170 static const char *v9fs_vfs_get_link(struct dentry *dentry,
1171 struct inode *inode,
1172 struct delayed_call *done)
1173 {
1174 struct v9fs_session_info *v9ses;
1175 struct p9_fid *fid;
1176 struct p9_wstat *st;
1177 char *res;
1178
1179 if (!dentry)
1180 return ERR_PTR(-ECHILD);
1181
1182 v9ses = v9fs_dentry2v9ses(dentry);
1183 if (!v9fs_proto_dotu(v9ses))
1184 return ERR_PTR(-EBADF);
1185
1186 p9_debug(P9_DEBUG_VFS, "%pd\n", dentry);
1187 fid = v9fs_fid_lookup(dentry);
1188
1189 if (IS_ERR(fid))
1190 return ERR_CAST(fid);
1191
1192 st = p9_client_stat(fid);
1193 p9_fid_put(fid);
1194 if (IS_ERR(st))
1195 return ERR_CAST(st);
1196
1197 if (!(st->mode & P9_DMSYMLINK)) {
1198 p9stat_free(st);
1199 kfree(st);
1200 return ERR_PTR(-EINVAL);
1201 }
1202 res = st->extension;
1203 st->extension = NULL;
1204 if (strlen(res) >= PATH_MAX)
1205 res[PATH_MAX - 1] = '\0';
1206
1207 p9stat_free(st);
1208 kfree(st);
1209 set_delayed_call(done, kfree_link, res);
1210 return res;
1211 }
1212
1213 /**
1214 * v9fs_vfs_mkspecial - create a special file
1215 * @dir: inode to create special file in
1216 * @dentry: dentry to create
1217 * @perm: mode to create special file
1218 * @extension: 9p2000.u format extension string representing special file
1219 *
1220 */
1221
v9fs_vfs_mkspecial(struct inode * dir,struct dentry * dentry,u32 perm,const char * extension)1222 static int v9fs_vfs_mkspecial(struct inode *dir, struct dentry *dentry,
1223 u32 perm, const char *extension)
1224 {
1225 struct p9_fid *fid;
1226 struct v9fs_session_info *v9ses;
1227
1228 v9ses = v9fs_inode2v9ses(dir);
1229 if (!v9fs_proto_dotu(v9ses)) {
1230 p9_debug(P9_DEBUG_ERROR, "not extended\n");
1231 return -EPERM;
1232 }
1233
1234 fid = v9fs_create(v9ses, dir, dentry, (char *) extension, perm,
1235 P9_OREAD);
1236 if (IS_ERR(fid))
1237 return PTR_ERR(fid);
1238
1239 v9fs_invalidate_inode_attr(dir);
1240 p9_fid_put(fid);
1241 return 0;
1242 }
1243
1244 /**
1245 * v9fs_vfs_symlink - helper function to create symlinks
1246 * @idmap: idmap of the mount
1247 * @dir: directory inode containing symlink
1248 * @dentry: dentry for symlink
1249 * @symname: symlink data
1250 *
1251 * See Also: 9P2000.u RFC for more information
1252 *
1253 */
1254
1255 static int
v9fs_vfs_symlink(const struct mnt_idmap * idmap,struct inode * dir,struct dentry * dentry,const char * symname)1256 v9fs_vfs_symlink(const struct mnt_idmap *idmap, struct inode *dir,
1257 struct dentry *dentry, const char *symname)
1258 {
1259 p9_debug(P9_DEBUG_VFS, " %llu,%pd,%s\n",
1260 dir->i_ino, dentry, symname);
1261
1262 return v9fs_vfs_mkspecial(dir, dentry, P9_DMSYMLINK, symname);
1263 }
1264
1265 #define U32_MAX_DIGITS 10
1266
1267 /**
1268 * v9fs_vfs_link - create a hardlink
1269 * @old_dentry: dentry for file to link to
1270 * @dir: inode destination for new link
1271 * @dentry: dentry for link
1272 *
1273 */
1274
1275 static int
v9fs_vfs_link(struct dentry * old_dentry,struct inode * dir,struct dentry * dentry)1276 v9fs_vfs_link(struct dentry *old_dentry, struct inode *dir,
1277 struct dentry *dentry)
1278 {
1279 int retval;
1280 char name[1 + U32_MAX_DIGITS + 2]; /* sign + number + \n + \0 */
1281 struct p9_fid *oldfid;
1282
1283 p9_debug(P9_DEBUG_VFS, " %llu,%pd,%pd\n",
1284 dir->i_ino, dentry, old_dentry);
1285
1286 oldfid = v9fs_fid_clone(old_dentry);
1287 if (IS_ERR(oldfid))
1288 return PTR_ERR(oldfid);
1289
1290 sprintf(name, "%d\n", oldfid->fid);
1291 retval = v9fs_vfs_mkspecial(dir, dentry, P9_DMLINK, name);
1292 if (!retval) {
1293 v9fs_refresh_inode(oldfid, d_inode(old_dentry));
1294 v9fs_invalidate_inode_attr(dir);
1295 }
1296 p9_fid_put(oldfid);
1297 return retval;
1298 }
1299
1300 /**
1301 * v9fs_vfs_mknod - create a special file
1302 * @idmap: idmap of the mount
1303 * @dir: inode destination for new link
1304 * @dentry: dentry for file
1305 * @mode: mode for creation
1306 * @rdev: device associated with special file
1307 *
1308 */
1309
1310 static int
v9fs_vfs_mknod(const struct mnt_idmap * idmap,struct inode * dir,struct dentry * dentry,umode_t mode,dev_t rdev)1311 v9fs_vfs_mknod(const struct mnt_idmap *idmap, struct inode *dir,
1312 struct dentry *dentry, umode_t mode, dev_t rdev)
1313 {
1314 struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dir);
1315 int retval;
1316 char name[2 + U32_MAX_DIGITS + 1 + U32_MAX_DIGITS + 1];
1317 u32 perm;
1318
1319 p9_debug(P9_DEBUG_VFS, " %llu,%pd mode: %x MAJOR: %u MINOR: %u\n",
1320 dir->i_ino, dentry, mode,
1321 MAJOR(rdev), MINOR(rdev));
1322
1323 /* build extension */
1324 if (S_ISBLK(mode))
1325 sprintf(name, "b %u %u", MAJOR(rdev), MINOR(rdev));
1326 else if (S_ISCHR(mode))
1327 sprintf(name, "c %u %u", MAJOR(rdev), MINOR(rdev));
1328 else
1329 *name = 0;
1330
1331 perm = unixmode2p9mode(v9ses, mode);
1332 retval = v9fs_vfs_mkspecial(dir, dentry, perm, name);
1333
1334 return retval;
1335 }
1336
v9fs_refresh_inode(struct p9_fid * fid,struct inode * inode)1337 int v9fs_refresh_inode(struct p9_fid *fid, struct inode *inode)
1338 {
1339 int umode;
1340 dev_t rdev;
1341 struct p9_wstat *st;
1342 struct v9fs_session_info *v9ses;
1343 unsigned int flags;
1344
1345 v9ses = v9fs_inode2v9ses(inode);
1346 st = p9_client_stat(fid);
1347 if (IS_ERR(st))
1348 return PTR_ERR(st);
1349 /*
1350 * Don't update inode if the file type is different
1351 */
1352 umode = p9mode2unixmode(v9ses, st, &rdev);
1353 if (inode_wrong_type(inode, umode))
1354 goto out;
1355
1356 /*
1357 * We don't want to refresh inode->i_size,
1358 * because we may have cached data
1359 */
1360 flags = (v9ses->cache & CACHE_LOOSE) ?
1361 V9FS_STAT2INODE_KEEP_ISIZE : 0;
1362 v9fs_stat2inode(st, inode, inode->i_sb, flags);
1363 out:
1364 p9stat_free(st);
1365 kfree(st);
1366 return 0;
1367 }
1368
1369 static const struct inode_operations v9fs_dir_inode_operations_dotu = {
1370 .create = v9fs_vfs_create,
1371 .lookup = v9fs_vfs_lookup,
1372 .atomic_open = v9fs_vfs_atomic_open,
1373 .symlink = v9fs_vfs_symlink,
1374 .link = v9fs_vfs_link,
1375 .unlink = v9fs_vfs_unlink,
1376 .mkdir = v9fs_vfs_mkdir,
1377 .rmdir = v9fs_vfs_rmdir,
1378 .mknod = v9fs_vfs_mknod,
1379 .rename = v9fs_vfs_rename,
1380 .getattr = v9fs_vfs_getattr,
1381 .setattr = v9fs_vfs_setattr,
1382 };
1383
1384 static const struct inode_operations v9fs_dir_inode_operations = {
1385 .create = v9fs_vfs_create,
1386 .lookup = v9fs_vfs_lookup,
1387 .atomic_open = v9fs_vfs_atomic_open,
1388 .unlink = v9fs_vfs_unlink,
1389 .mkdir = v9fs_vfs_mkdir,
1390 .rmdir = v9fs_vfs_rmdir,
1391 .mknod = v9fs_vfs_mknod,
1392 .rename = v9fs_vfs_rename,
1393 .getattr = v9fs_vfs_getattr,
1394 .setattr = v9fs_vfs_setattr,
1395 };
1396
1397 static const struct inode_operations v9fs_file_inode_operations = {
1398 .getattr = v9fs_vfs_getattr,
1399 .setattr = v9fs_vfs_setattr,
1400 };
1401
1402 static const struct inode_operations v9fs_symlink_inode_operations = {
1403 .get_link = v9fs_vfs_get_link,
1404 .getattr = v9fs_vfs_getattr,
1405 .setattr = v9fs_vfs_setattr,
1406 };
1407