xref: /linux/fs/9p/vfs_inode_dotl.c (revision 8137a49e1567726eb10fcf55ad141ac19804ca6b)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  linux/fs/9p/vfs_inode_dotl.c
4  *
5  * This file contains vfs inode ops for the 9P2000.L 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 #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/idr.h>
21 #include <linux/sched.h>
22 #include <linux/slab.h>
23 #include <linux/xattr.h>
24 #include <linux/posix_acl.h>
25 #include <net/9p/9p.h>
26 #include <net/9p/client.h>
27 
28 #include "v9fs.h"
29 #include "v9fs_vfs.h"
30 #include "fid.h"
31 #include "cache.h"
32 #include "xattr.h"
33 #include "acl.h"
34 
35 static int
36 v9fs_vfs_mknod_dotl(struct user_namespace *mnt_userns, struct inode *dir,
37 		    struct dentry *dentry, umode_t omode, dev_t rdev);
38 
39 /**
40  * v9fs_get_fsgid_for_create - Helper function to get the gid for creating a
41  * new file system object. This checks the S_ISGID to determine the owning
42  * group of the new file system object.
43  */
44 
45 static kgid_t v9fs_get_fsgid_for_create(struct inode *dir_inode)
46 {
47 	BUG_ON(dir_inode == NULL);
48 
49 	if (dir_inode->i_mode & S_ISGID) {
50 		/* set_gid bit is set.*/
51 		return dir_inode->i_gid;
52 	}
53 	return current_fsgid();
54 }
55 
56 static int v9fs_test_inode_dotl(struct inode *inode, void *data)
57 {
58 	struct v9fs_inode *v9inode = V9FS_I(inode);
59 	struct p9_stat_dotl *st = (struct p9_stat_dotl *)data;
60 
61 	/* don't match inode of different type */
62 	if (inode_wrong_type(inode, st->st_mode))
63 		return 0;
64 
65 	if (inode->i_generation != st->st_gen)
66 		return 0;
67 
68 	/* compare qid details */
69 	if (memcmp(&v9inode->qid.version,
70 		   &st->qid.version, sizeof(v9inode->qid.version)))
71 		return 0;
72 
73 	if (v9inode->qid.type != st->qid.type)
74 		return 0;
75 
76 	if (v9inode->qid.path != st->qid.path)
77 		return 0;
78 	return 1;
79 }
80 
81 /* Always get a new inode */
82 static int v9fs_test_new_inode_dotl(struct inode *inode, void *data)
83 {
84 	return 0;
85 }
86 
87 static int v9fs_set_inode_dotl(struct inode *inode,  void *data)
88 {
89 	struct v9fs_inode *v9inode = V9FS_I(inode);
90 	struct p9_stat_dotl *st = (struct p9_stat_dotl *)data;
91 
92 	memcpy(&v9inode->qid, &st->qid, sizeof(st->qid));
93 	inode->i_generation = st->st_gen;
94 	return 0;
95 }
96 
97 static struct inode *v9fs_qid_iget_dotl(struct super_block *sb,
98 					struct p9_qid *qid,
99 					struct p9_fid *fid,
100 					struct p9_stat_dotl *st,
101 					int new)
102 {
103 	int retval;
104 	unsigned long i_ino;
105 	struct inode *inode;
106 	struct v9fs_session_info *v9ses = sb->s_fs_info;
107 	int (*test)(struct inode *, void *);
108 
109 	if (new)
110 		test = v9fs_test_new_inode_dotl;
111 	else
112 		test = v9fs_test_inode_dotl;
113 
114 	i_ino = v9fs_qid2ino(qid);
115 	inode = iget5_locked(sb, i_ino, test, v9fs_set_inode_dotl, st);
116 	if (!inode)
117 		return ERR_PTR(-ENOMEM);
118 	if (!(inode->i_state & I_NEW))
119 		return inode;
120 	/*
121 	 * initialize the inode with the stat info
122 	 * FIXME!! we may need support for stale inodes
123 	 * later.
124 	 */
125 	inode->i_ino = i_ino;
126 	retval = v9fs_init_inode(v9ses, inode,
127 				 st->st_mode, new_decode_dev(st->st_rdev));
128 	if (retval)
129 		goto error;
130 
131 	v9fs_stat2inode_dotl(st, inode, 0);
132 	v9fs_cache_inode_get_cookie(inode);
133 	retval = v9fs_get_acl(inode, fid);
134 	if (retval)
135 		goto error;
136 
137 	unlock_new_inode(inode);
138 	return inode;
139 error:
140 	iget_failed(inode);
141 	return ERR_PTR(retval);
142 
143 }
144 
145 struct inode *
146 v9fs_inode_from_fid_dotl(struct v9fs_session_info *v9ses, struct p9_fid *fid,
147 			 struct super_block *sb, int new)
148 {
149 	struct p9_stat_dotl *st;
150 	struct inode *inode = NULL;
151 
152 	st = p9_client_getattr_dotl(fid, P9_STATS_BASIC | P9_STATS_GEN);
153 	if (IS_ERR(st))
154 		return ERR_CAST(st);
155 
156 	inode = v9fs_qid_iget_dotl(sb, &st->qid, fid, st, new);
157 	kfree(st);
158 	return inode;
159 }
160 
161 struct dotl_openflag_map {
162 	int open_flag;
163 	int dotl_flag;
164 };
165 
166 static int v9fs_mapped_dotl_flags(int flags)
167 {
168 	int i;
169 	int rflags = 0;
170 	struct dotl_openflag_map dotl_oflag_map[] = {
171 		{ O_CREAT,	P9_DOTL_CREATE },
172 		{ O_EXCL,	P9_DOTL_EXCL },
173 		{ O_NOCTTY,	P9_DOTL_NOCTTY },
174 		{ O_APPEND,	P9_DOTL_APPEND },
175 		{ O_NONBLOCK,	P9_DOTL_NONBLOCK },
176 		{ O_DSYNC,	P9_DOTL_DSYNC },
177 		{ FASYNC,	P9_DOTL_FASYNC },
178 		{ O_DIRECT,	P9_DOTL_DIRECT },
179 		{ O_LARGEFILE,	P9_DOTL_LARGEFILE },
180 		{ O_DIRECTORY,	P9_DOTL_DIRECTORY },
181 		{ O_NOFOLLOW,	P9_DOTL_NOFOLLOW },
182 		{ O_NOATIME,	P9_DOTL_NOATIME },
183 		{ O_CLOEXEC,	P9_DOTL_CLOEXEC },
184 		{ O_SYNC,	P9_DOTL_SYNC},
185 	};
186 	for (i = 0; i < ARRAY_SIZE(dotl_oflag_map); i++) {
187 		if (flags & dotl_oflag_map[i].open_flag)
188 			rflags |= dotl_oflag_map[i].dotl_flag;
189 	}
190 	return rflags;
191 }
192 
193 /**
194  * v9fs_open_to_dotl_flags- convert Linux specific open flags to
195  * plan 9 open flag.
196  * @flags: flags to convert
197  */
198 int v9fs_open_to_dotl_flags(int flags)
199 {
200 	int rflags = 0;
201 
202 	/*
203 	 * We have same bits for P9_DOTL_READONLY, P9_DOTL_WRONLY
204 	 * and P9_DOTL_NOACCESS
205 	 */
206 	rflags |= flags & O_ACCMODE;
207 	rflags |= v9fs_mapped_dotl_flags(flags);
208 
209 	return rflags;
210 }
211 
212 /**
213  * v9fs_vfs_create_dotl - VFS hook to create files for 9P2000.L protocol.
214  * @dir: directory inode that is being created
215  * @dentry:  dentry that is being deleted
216  * @omode: create permissions
217  *
218  */
219 
220 static int
221 v9fs_vfs_create_dotl(struct user_namespace *mnt_userns, struct inode *dir,
222 		     struct dentry *dentry, umode_t omode, bool excl)
223 {
224 	return v9fs_vfs_mknod_dotl(mnt_userns, dir, dentry, omode, 0);
225 }
226 
227 static int
228 v9fs_vfs_atomic_open_dotl(struct inode *dir, struct dentry *dentry,
229 			  struct file *file, unsigned flags, umode_t omode)
230 {
231 	int err = 0;
232 	kgid_t gid;
233 	umode_t mode;
234 	const unsigned char *name = NULL;
235 	struct p9_qid qid;
236 	struct inode *inode;
237 	struct p9_fid *fid = NULL;
238 	struct v9fs_inode *v9inode;
239 	struct p9_fid *dfid, *ofid, *inode_fid;
240 	struct v9fs_session_info *v9ses;
241 	struct posix_acl *pacl = NULL, *dacl = NULL;
242 	struct dentry *res = NULL;
243 
244 	if (d_in_lookup(dentry)) {
245 		res = v9fs_vfs_lookup(dir, dentry, 0);
246 		if (IS_ERR(res))
247 			return PTR_ERR(res);
248 
249 		if (res)
250 			dentry = res;
251 	}
252 
253 	/* Only creates */
254 	if (!(flags & O_CREAT) || d_really_is_positive(dentry))
255 		return	finish_no_open(file, res);
256 
257 	v9ses = v9fs_inode2v9ses(dir);
258 
259 	name = dentry->d_name.name;
260 	p9_debug(P9_DEBUG_VFS, "name:%s flags:0x%x mode:0x%hx\n",
261 		 name, flags, omode);
262 
263 	dfid = v9fs_parent_fid(dentry);
264 	if (IS_ERR(dfid)) {
265 		err = PTR_ERR(dfid);
266 		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
267 		goto out;
268 	}
269 
270 	/* clone a fid to use for creation */
271 	ofid = clone_fid(dfid);
272 	if (IS_ERR(ofid)) {
273 		err = PTR_ERR(ofid);
274 		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
275 		goto out;
276 	}
277 
278 	gid = v9fs_get_fsgid_for_create(dir);
279 
280 	mode = omode;
281 	/* Update mode based on ACL value */
282 	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
283 	if (err) {
284 		p9_debug(P9_DEBUG_VFS, "Failed to get acl values in creat %d\n",
285 			 err);
286 		goto error;
287 	}
288 	err = p9_client_create_dotl(ofid, name, v9fs_open_to_dotl_flags(flags),
289 				    mode, gid, &qid);
290 	if (err < 0) {
291 		p9_debug(P9_DEBUG_VFS, "p9_client_open_dotl failed in creat %d\n",
292 			 err);
293 		goto error;
294 	}
295 	v9fs_invalidate_inode_attr(dir);
296 
297 	/* instantiate inode and assign the unopened fid to the dentry */
298 	fid = p9_client_walk(dfid, 1, &name, 1);
299 	p9_client_clunk(dfid);
300 	if (IS_ERR(fid)) {
301 		err = PTR_ERR(fid);
302 		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
303 		fid = NULL;
304 		goto error;
305 	}
306 	inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
307 	if (IS_ERR(inode)) {
308 		err = PTR_ERR(inode);
309 		p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n", err);
310 		goto error;
311 	}
312 	/* Now set the ACL based on the default value */
313 	v9fs_set_create_acl(inode, fid, dacl, pacl);
314 
315 	v9fs_fid_add(dentry, fid);
316 	d_instantiate(dentry, inode);
317 
318 	v9inode = V9FS_I(inode);
319 	mutex_lock(&v9inode->v_mutex);
320 	if ((v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) &&
321 	    !v9inode->writeback_fid &&
322 	    ((flags & O_ACCMODE) != O_RDONLY)) {
323 		/*
324 		 * clone a fid and add it to writeback_fid
325 		 * we do it during open time instead of
326 		 * page dirty time via write_begin/page_mkwrite
327 		 * because we want write after unlink usecase
328 		 * to work.
329 		 */
330 		inode_fid = v9fs_writeback_fid(dentry);
331 		if (IS_ERR(inode_fid)) {
332 			err = PTR_ERR(inode_fid);
333 			mutex_unlock(&v9inode->v_mutex);
334 			goto err_clunk_old_fid;
335 		}
336 		v9inode->writeback_fid = (void *) inode_fid;
337 	}
338 	mutex_unlock(&v9inode->v_mutex);
339 	/* Since we are opening a file, assign the open fid to the file */
340 	err = finish_open(file, dentry, generic_file_open);
341 	if (err)
342 		goto err_clunk_old_fid;
343 	file->private_data = ofid;
344 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
345 		v9fs_cache_inode_set_cookie(inode, file);
346 	v9fs_open_fid_add(inode, ofid);
347 	file->f_mode |= FMODE_CREATED;
348 out:
349 	v9fs_put_acl(dacl, pacl);
350 	dput(res);
351 	return err;
352 
353 error:
354 	if (fid)
355 		p9_client_clunk(fid);
356 err_clunk_old_fid:
357 	if (ofid)
358 		p9_client_clunk(ofid);
359 	goto out;
360 }
361 
362 /**
363  * v9fs_vfs_mkdir_dotl - VFS mkdir hook to create a directory
364  * @dir:  inode that is being unlinked
365  * @dentry: dentry that is being unlinked
366  * @omode: mode for new directory
367  *
368  */
369 
370 static int v9fs_vfs_mkdir_dotl(struct user_namespace *mnt_userns,
371 			       struct inode *dir, struct dentry *dentry,
372 			       umode_t omode)
373 {
374 	int err;
375 	struct v9fs_session_info *v9ses;
376 	struct p9_fid *fid = NULL, *dfid = NULL;
377 	kgid_t gid;
378 	const unsigned char *name;
379 	umode_t mode;
380 	struct inode *inode;
381 	struct p9_qid qid;
382 	struct posix_acl *dacl = NULL, *pacl = NULL;
383 
384 	p9_debug(P9_DEBUG_VFS, "name %pd\n", dentry);
385 	err = 0;
386 	v9ses = v9fs_inode2v9ses(dir);
387 
388 	omode |= S_IFDIR;
389 	if (dir->i_mode & S_ISGID)
390 		omode |= S_ISGID;
391 
392 	dfid = v9fs_parent_fid(dentry);
393 	if (IS_ERR(dfid)) {
394 		err = PTR_ERR(dfid);
395 		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
396 		dfid = NULL;
397 		goto error;
398 	}
399 
400 	gid = v9fs_get_fsgid_for_create(dir);
401 	mode = omode;
402 	/* Update mode based on ACL value */
403 	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
404 	if (err) {
405 		p9_debug(P9_DEBUG_VFS, "Failed to get acl values in mkdir %d\n",
406 			 err);
407 		goto error;
408 	}
409 	name = dentry->d_name.name;
410 	err = p9_client_mkdir_dotl(dfid, name, mode, gid, &qid);
411 	if (err < 0)
412 		goto error;
413 	fid = p9_client_walk(dfid, 1, &name, 1);
414 	if (IS_ERR(fid)) {
415 		err = PTR_ERR(fid);
416 		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
417 			 err);
418 		fid = NULL;
419 		goto error;
420 	}
421 
422 	/* instantiate inode and assign the unopened fid to the dentry */
423 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
424 		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
425 		if (IS_ERR(inode)) {
426 			err = PTR_ERR(inode);
427 			p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n",
428 				 err);
429 			goto error;
430 		}
431 		v9fs_fid_add(dentry, fid);
432 		v9fs_set_create_acl(inode, fid, dacl, pacl);
433 		d_instantiate(dentry, inode);
434 		fid = NULL;
435 		err = 0;
436 	} else {
437 		/*
438 		 * Not in cached mode. No need to populate
439 		 * inode with stat. We need to get an inode
440 		 * so that we can set the acl with dentry
441 		 */
442 		inode = v9fs_get_inode(dir->i_sb, mode, 0);
443 		if (IS_ERR(inode)) {
444 			err = PTR_ERR(inode);
445 			goto error;
446 		}
447 		v9fs_set_create_acl(inode, fid, dacl, pacl);
448 		d_instantiate(dentry, inode);
449 	}
450 	inc_nlink(dir);
451 	v9fs_invalidate_inode_attr(dir);
452 error:
453 	if (fid)
454 		p9_client_clunk(fid);
455 	v9fs_put_acl(dacl, pacl);
456 	p9_client_clunk(dfid);
457 	return err;
458 }
459 
460 static int
461 v9fs_vfs_getattr_dotl(struct user_namespace *mnt_userns,
462 		      const struct path *path, struct kstat *stat,
463 		      u32 request_mask, unsigned int flags)
464 {
465 	struct dentry *dentry = path->dentry;
466 	struct v9fs_session_info *v9ses;
467 	struct p9_fid *fid;
468 	struct p9_stat_dotl *st;
469 
470 	p9_debug(P9_DEBUG_VFS, "dentry: %p\n", dentry);
471 	v9ses = v9fs_dentry2v9ses(dentry);
472 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
473 		generic_fillattr(&init_user_ns, d_inode(dentry), stat);
474 		return 0;
475 	}
476 	fid = v9fs_fid_lookup(dentry);
477 	if (IS_ERR(fid))
478 		return PTR_ERR(fid);
479 
480 	/* Ask for all the fields in stat structure. Server will return
481 	 * whatever it supports
482 	 */
483 
484 	st = p9_client_getattr_dotl(fid, P9_STATS_ALL);
485 	p9_client_clunk(fid);
486 	if (IS_ERR(st))
487 		return PTR_ERR(st);
488 
489 	v9fs_stat2inode_dotl(st, d_inode(dentry), 0);
490 	generic_fillattr(&init_user_ns, d_inode(dentry), stat);
491 	/* Change block size to what the server returned */
492 	stat->blksize = st->st_blksize;
493 
494 	kfree(st);
495 	return 0;
496 }
497 
498 /*
499  * Attribute flags.
500  */
501 #define P9_ATTR_MODE		(1 << 0)
502 #define P9_ATTR_UID		(1 << 1)
503 #define P9_ATTR_GID		(1 << 2)
504 #define P9_ATTR_SIZE		(1 << 3)
505 #define P9_ATTR_ATIME		(1 << 4)
506 #define P9_ATTR_MTIME		(1 << 5)
507 #define P9_ATTR_CTIME		(1 << 6)
508 #define P9_ATTR_ATIME_SET	(1 << 7)
509 #define P9_ATTR_MTIME_SET	(1 << 8)
510 
511 struct dotl_iattr_map {
512 	int iattr_valid;
513 	int p9_iattr_valid;
514 };
515 
516 static int v9fs_mapped_iattr_valid(int iattr_valid)
517 {
518 	int i;
519 	int p9_iattr_valid = 0;
520 	struct dotl_iattr_map dotl_iattr_map[] = {
521 		{ ATTR_MODE,		P9_ATTR_MODE },
522 		{ ATTR_UID,		P9_ATTR_UID },
523 		{ ATTR_GID,		P9_ATTR_GID },
524 		{ ATTR_SIZE,		P9_ATTR_SIZE },
525 		{ ATTR_ATIME,		P9_ATTR_ATIME },
526 		{ ATTR_MTIME,		P9_ATTR_MTIME },
527 		{ ATTR_CTIME,		P9_ATTR_CTIME },
528 		{ ATTR_ATIME_SET,	P9_ATTR_ATIME_SET },
529 		{ ATTR_MTIME_SET,	P9_ATTR_MTIME_SET },
530 	};
531 	for (i = 0; i < ARRAY_SIZE(dotl_iattr_map); i++) {
532 		if (iattr_valid & dotl_iattr_map[i].iattr_valid)
533 			p9_iattr_valid |= dotl_iattr_map[i].p9_iattr_valid;
534 	}
535 	return p9_iattr_valid;
536 }
537 
538 /**
539  * v9fs_vfs_setattr_dotl - set file metadata
540  * @dentry: file whose metadata to set
541  * @iattr: metadata assignment structure
542  *
543  */
544 
545 int v9fs_vfs_setattr_dotl(struct user_namespace *mnt_userns,
546 			  struct dentry *dentry, struct iattr *iattr)
547 {
548 	int retval, use_dentry = 0;
549 	struct p9_fid *fid = NULL;
550 	struct p9_iattr_dotl p9attr;
551 	struct inode *inode = d_inode(dentry);
552 
553 	p9_debug(P9_DEBUG_VFS, "\n");
554 
555 	retval = setattr_prepare(&init_user_ns, dentry, iattr);
556 	if (retval)
557 		return retval;
558 
559 	p9attr.valid = v9fs_mapped_iattr_valid(iattr->ia_valid);
560 	p9attr.mode = iattr->ia_mode;
561 	p9attr.uid = iattr->ia_uid;
562 	p9attr.gid = iattr->ia_gid;
563 	p9attr.size = iattr->ia_size;
564 	p9attr.atime_sec = iattr->ia_atime.tv_sec;
565 	p9attr.atime_nsec = iattr->ia_atime.tv_nsec;
566 	p9attr.mtime_sec = iattr->ia_mtime.tv_sec;
567 	p9attr.mtime_nsec = iattr->ia_mtime.tv_nsec;
568 
569 	if (iattr->ia_valid & ATTR_FILE) {
570 		fid = iattr->ia_file->private_data;
571 		WARN_ON(!fid);
572 	}
573 	if (!fid) {
574 		fid = v9fs_fid_lookup(dentry);
575 		use_dentry = 1;
576 	}
577 	if (IS_ERR(fid))
578 		return PTR_ERR(fid);
579 
580 	/* Write all dirty data */
581 	if (S_ISREG(inode->i_mode))
582 		filemap_write_and_wait(inode->i_mapping);
583 
584 	retval = p9_client_setattr(fid, &p9attr);
585 	if (retval < 0) {
586 		if (use_dentry)
587 			p9_client_clunk(fid);
588 		return retval;
589 	}
590 
591 	if ((iattr->ia_valid & ATTR_SIZE) &&
592 	    iattr->ia_size != i_size_read(inode))
593 		truncate_setsize(inode, iattr->ia_size);
594 
595 	v9fs_invalidate_inode_attr(inode);
596 	setattr_copy(&init_user_ns, inode, iattr);
597 	mark_inode_dirty(inode);
598 	if (iattr->ia_valid & ATTR_MODE) {
599 		/* We also want to update ACL when we update mode bits */
600 		retval = v9fs_acl_chmod(inode, fid);
601 		if (retval < 0) {
602 			if (use_dentry)
603 				p9_client_clunk(fid);
604 			return retval;
605 		}
606 	}
607 	if (use_dentry)
608 		p9_client_clunk(fid);
609 
610 	return 0;
611 }
612 
613 /**
614  * v9fs_stat2inode_dotl - populate an inode structure with stat info
615  * @stat: stat structure
616  * @inode: inode to populate
617  * @flags: ctrl flags (e.g. V9FS_STAT2INODE_KEEP_ISIZE)
618  *
619  */
620 
621 void
622 v9fs_stat2inode_dotl(struct p9_stat_dotl *stat, struct inode *inode,
623 		      unsigned int flags)
624 {
625 	umode_t mode;
626 	struct v9fs_inode *v9inode = V9FS_I(inode);
627 
628 	if ((stat->st_result_mask & P9_STATS_BASIC) == P9_STATS_BASIC) {
629 		inode->i_atime.tv_sec = stat->st_atime_sec;
630 		inode->i_atime.tv_nsec = stat->st_atime_nsec;
631 		inode->i_mtime.tv_sec = stat->st_mtime_sec;
632 		inode->i_mtime.tv_nsec = stat->st_mtime_nsec;
633 		inode->i_ctime.tv_sec = stat->st_ctime_sec;
634 		inode->i_ctime.tv_nsec = stat->st_ctime_nsec;
635 		inode->i_uid = stat->st_uid;
636 		inode->i_gid = stat->st_gid;
637 		set_nlink(inode, stat->st_nlink);
638 
639 		mode = stat->st_mode & S_IALLUGO;
640 		mode |= inode->i_mode & ~S_IALLUGO;
641 		inode->i_mode = mode;
642 
643 		if (!(flags & V9FS_STAT2INODE_KEEP_ISIZE))
644 			v9fs_i_size_write(inode, stat->st_size);
645 		inode->i_blocks = stat->st_blocks;
646 	} else {
647 		if (stat->st_result_mask & P9_STATS_ATIME) {
648 			inode->i_atime.tv_sec = stat->st_atime_sec;
649 			inode->i_atime.tv_nsec = stat->st_atime_nsec;
650 		}
651 		if (stat->st_result_mask & P9_STATS_MTIME) {
652 			inode->i_mtime.tv_sec = stat->st_mtime_sec;
653 			inode->i_mtime.tv_nsec = stat->st_mtime_nsec;
654 		}
655 		if (stat->st_result_mask & P9_STATS_CTIME) {
656 			inode->i_ctime.tv_sec = stat->st_ctime_sec;
657 			inode->i_ctime.tv_nsec = stat->st_ctime_nsec;
658 		}
659 		if (stat->st_result_mask & P9_STATS_UID)
660 			inode->i_uid = stat->st_uid;
661 		if (stat->st_result_mask & P9_STATS_GID)
662 			inode->i_gid = stat->st_gid;
663 		if (stat->st_result_mask & P9_STATS_NLINK)
664 			set_nlink(inode, stat->st_nlink);
665 		if (stat->st_result_mask & P9_STATS_MODE) {
666 			mode = stat->st_mode & S_IALLUGO;
667 			mode |= inode->i_mode & ~S_IALLUGO;
668 			inode->i_mode = mode;
669 		}
670 		if (!(flags & V9FS_STAT2INODE_KEEP_ISIZE) &&
671 		    stat->st_result_mask & P9_STATS_SIZE)
672 			v9fs_i_size_write(inode, stat->st_size);
673 		if (stat->st_result_mask & P9_STATS_BLOCKS)
674 			inode->i_blocks = stat->st_blocks;
675 	}
676 	if (stat->st_result_mask & P9_STATS_GEN)
677 		inode->i_generation = stat->st_gen;
678 
679 	/* Currently we don't support P9_STATS_BTIME and P9_STATS_DATA_VERSION
680 	 * because the inode structure does not have fields for them.
681 	 */
682 	v9inode->cache_validity &= ~V9FS_INO_INVALID_ATTR;
683 }
684 
685 static int
686 v9fs_vfs_symlink_dotl(struct user_namespace *mnt_userns, struct inode *dir,
687 		      struct dentry *dentry, const char *symname)
688 {
689 	int err;
690 	kgid_t gid;
691 	const unsigned char *name;
692 	struct p9_qid qid;
693 	struct inode *inode;
694 	struct p9_fid *dfid;
695 	struct p9_fid *fid = NULL;
696 	struct v9fs_session_info *v9ses;
697 
698 	name = dentry->d_name.name;
699 	p9_debug(P9_DEBUG_VFS, "%lu,%s,%s\n", dir->i_ino, name, symname);
700 	v9ses = v9fs_inode2v9ses(dir);
701 
702 	dfid = v9fs_parent_fid(dentry);
703 	if (IS_ERR(dfid)) {
704 		err = PTR_ERR(dfid);
705 		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
706 		return err;
707 	}
708 
709 	gid = v9fs_get_fsgid_for_create(dir);
710 
711 	/* Server doesn't alter fid on TSYMLINK. Hence no need to clone it. */
712 	err = p9_client_symlink(dfid, name, symname, gid, &qid);
713 
714 	if (err < 0) {
715 		p9_debug(P9_DEBUG_VFS, "p9_client_symlink failed %d\n", err);
716 		goto error;
717 	}
718 
719 	v9fs_invalidate_inode_attr(dir);
720 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
721 		/* Now walk from the parent so we can get an unopened fid. */
722 		fid = p9_client_walk(dfid, 1, &name, 1);
723 		if (IS_ERR(fid)) {
724 			err = PTR_ERR(fid);
725 			p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
726 				 err);
727 			fid = NULL;
728 			goto error;
729 		}
730 
731 		/* instantiate inode and assign the unopened fid to dentry */
732 		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
733 		if (IS_ERR(inode)) {
734 			err = PTR_ERR(inode);
735 			p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n",
736 				 err);
737 			goto error;
738 		}
739 		v9fs_fid_add(dentry, fid);
740 		d_instantiate(dentry, inode);
741 		fid = NULL;
742 		err = 0;
743 	} else {
744 		/* Not in cached mode. No need to populate inode with stat */
745 		inode = v9fs_get_inode(dir->i_sb, S_IFLNK, 0);
746 		if (IS_ERR(inode)) {
747 			err = PTR_ERR(inode);
748 			goto error;
749 		}
750 		d_instantiate(dentry, inode);
751 	}
752 
753 error:
754 	if (fid)
755 		p9_client_clunk(fid);
756 
757 	p9_client_clunk(dfid);
758 	return err;
759 }
760 
761 /**
762  * v9fs_vfs_link_dotl - create a hardlink for dotl
763  * @old_dentry: dentry for file to link to
764  * @dir: inode destination for new link
765  * @dentry: dentry for link
766  *
767  */
768 
769 static int
770 v9fs_vfs_link_dotl(struct dentry *old_dentry, struct inode *dir,
771 		struct dentry *dentry)
772 {
773 	int err;
774 	struct p9_fid *dfid, *oldfid;
775 	struct v9fs_session_info *v9ses;
776 
777 	p9_debug(P9_DEBUG_VFS, "dir ino: %lu, old_name: %pd, new_name: %pd\n",
778 		 dir->i_ino, old_dentry, dentry);
779 
780 	v9ses = v9fs_inode2v9ses(dir);
781 	dfid = v9fs_parent_fid(dentry);
782 	if (IS_ERR(dfid))
783 		return PTR_ERR(dfid);
784 
785 	oldfid = v9fs_fid_lookup(old_dentry);
786 	if (IS_ERR(oldfid)) {
787 		p9_client_clunk(dfid);
788 		return PTR_ERR(oldfid);
789 	}
790 
791 	err = p9_client_link(dfid, oldfid, dentry->d_name.name);
792 
793 	p9_client_clunk(dfid);
794 	p9_client_clunk(oldfid);
795 	if (err < 0) {
796 		p9_debug(P9_DEBUG_VFS, "p9_client_link failed %d\n", err);
797 		return err;
798 	}
799 
800 	v9fs_invalidate_inode_attr(dir);
801 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
802 		/* Get the latest stat info from server. */
803 		struct p9_fid *fid;
804 		fid = v9fs_fid_lookup(old_dentry);
805 		if (IS_ERR(fid))
806 			return PTR_ERR(fid);
807 
808 		v9fs_refresh_inode_dotl(fid, d_inode(old_dentry));
809 		p9_client_clunk(fid);
810 	}
811 	ihold(d_inode(old_dentry));
812 	d_instantiate(dentry, d_inode(old_dentry));
813 
814 	return err;
815 }
816 
817 /**
818  * v9fs_vfs_mknod_dotl - create a special file
819  * @dir: inode destination for new link
820  * @dentry: dentry for file
821  * @omode: mode for creation
822  * @rdev: device associated with special file
823  *
824  */
825 static int
826 v9fs_vfs_mknod_dotl(struct user_namespace *mnt_userns, struct inode *dir,
827 		    struct dentry *dentry, umode_t omode, dev_t rdev)
828 {
829 	int err;
830 	kgid_t gid;
831 	const unsigned char *name;
832 	umode_t mode;
833 	struct v9fs_session_info *v9ses;
834 	struct p9_fid *fid = NULL, *dfid = NULL;
835 	struct inode *inode;
836 	struct p9_qid qid;
837 	struct posix_acl *dacl = NULL, *pacl = NULL;
838 
839 	p9_debug(P9_DEBUG_VFS, " %lu,%pd mode: %hx MAJOR: %u MINOR: %u\n",
840 		 dir->i_ino, dentry, omode,
841 		 MAJOR(rdev), MINOR(rdev));
842 
843 	v9ses = v9fs_inode2v9ses(dir);
844 	dfid = v9fs_parent_fid(dentry);
845 	if (IS_ERR(dfid)) {
846 		err = PTR_ERR(dfid);
847 		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
848 		dfid = NULL;
849 		goto error;
850 	}
851 
852 	gid = v9fs_get_fsgid_for_create(dir);
853 	mode = omode;
854 	/* Update mode based on ACL value */
855 	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
856 	if (err) {
857 		p9_debug(P9_DEBUG_VFS, "Failed to get acl values in mknod %d\n",
858 			 err);
859 		goto error;
860 	}
861 	name = dentry->d_name.name;
862 
863 	err = p9_client_mknod_dotl(dfid, name, mode, rdev, gid, &qid);
864 	if (err < 0)
865 		goto error;
866 
867 	v9fs_invalidate_inode_attr(dir);
868 	fid = p9_client_walk(dfid, 1, &name, 1);
869 	if (IS_ERR(fid)) {
870 		err = PTR_ERR(fid);
871 		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
872 			 err);
873 		fid = NULL;
874 		goto error;
875 	}
876 
877 	/* instantiate inode and assign the unopened fid to the dentry */
878 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
879 		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
880 		if (IS_ERR(inode)) {
881 			err = PTR_ERR(inode);
882 			p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n",
883 				 err);
884 			goto error;
885 		}
886 		v9fs_set_create_acl(inode, fid, dacl, pacl);
887 		v9fs_fid_add(dentry, fid);
888 		d_instantiate(dentry, inode);
889 		fid = NULL;
890 		err = 0;
891 	} else {
892 		/*
893 		 * Not in cached mode. No need to populate inode with stat.
894 		 * socket syscall returns a fd, so we need instantiate
895 		 */
896 		inode = v9fs_get_inode(dir->i_sb, mode, rdev);
897 		if (IS_ERR(inode)) {
898 			err = PTR_ERR(inode);
899 			goto error;
900 		}
901 		v9fs_set_create_acl(inode, fid, dacl, pacl);
902 		d_instantiate(dentry, inode);
903 	}
904 error:
905 	if (fid)
906 		p9_client_clunk(fid);
907 	v9fs_put_acl(dacl, pacl);
908 	p9_client_clunk(dfid);
909 
910 	return err;
911 }
912 
913 /**
914  * v9fs_vfs_get_link_dotl - follow a symlink path
915  * @dentry: dentry for symlink
916  * @inode: inode for symlink
917  * @done: destructor for return value
918  */
919 
920 static const char *
921 v9fs_vfs_get_link_dotl(struct dentry *dentry,
922 		       struct inode *inode,
923 		       struct delayed_call *done)
924 {
925 	struct p9_fid *fid;
926 	char *target;
927 	int retval;
928 
929 	if (!dentry)
930 		return ERR_PTR(-ECHILD);
931 
932 	p9_debug(P9_DEBUG_VFS, "%pd\n", dentry);
933 
934 	fid = v9fs_fid_lookup(dentry);
935 	if (IS_ERR(fid))
936 		return ERR_CAST(fid);
937 	retval = p9_client_readlink(fid, &target);
938 	p9_client_clunk(fid);
939 	if (retval)
940 		return ERR_PTR(retval);
941 	set_delayed_call(done, kfree_link, target);
942 	return target;
943 }
944 
945 int v9fs_refresh_inode_dotl(struct p9_fid *fid, struct inode *inode)
946 {
947 	struct p9_stat_dotl *st;
948 	struct v9fs_session_info *v9ses;
949 	unsigned int flags;
950 
951 	v9ses = v9fs_inode2v9ses(inode);
952 	st = p9_client_getattr_dotl(fid, P9_STATS_ALL);
953 	if (IS_ERR(st))
954 		return PTR_ERR(st);
955 	/*
956 	 * Don't update inode if the file type is different
957 	 */
958 	if (inode_wrong_type(inode, st->st_mode))
959 		goto out;
960 
961 	/*
962 	 * We don't want to refresh inode->i_size,
963 	 * because we may have cached data
964 	 */
965 	flags = (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) ?
966 		V9FS_STAT2INODE_KEEP_ISIZE : 0;
967 	v9fs_stat2inode_dotl(st, inode, flags);
968 out:
969 	kfree(st);
970 	return 0;
971 }
972 
973 const struct inode_operations v9fs_dir_inode_operations_dotl = {
974 	.create = v9fs_vfs_create_dotl,
975 	.atomic_open = v9fs_vfs_atomic_open_dotl,
976 	.lookup = v9fs_vfs_lookup,
977 	.link = v9fs_vfs_link_dotl,
978 	.symlink = v9fs_vfs_symlink_dotl,
979 	.unlink = v9fs_vfs_unlink,
980 	.mkdir = v9fs_vfs_mkdir_dotl,
981 	.rmdir = v9fs_vfs_rmdir,
982 	.mknod = v9fs_vfs_mknod_dotl,
983 	.rename = v9fs_vfs_rename,
984 	.getattr = v9fs_vfs_getattr_dotl,
985 	.setattr = v9fs_vfs_setattr_dotl,
986 	.listxattr = v9fs_listxattr,
987 	.get_acl = v9fs_iop_get_acl,
988 };
989 
990 const struct inode_operations v9fs_file_inode_operations_dotl = {
991 	.getattr = v9fs_vfs_getattr_dotl,
992 	.setattr = v9fs_vfs_setattr_dotl,
993 	.listxattr = v9fs_listxattr,
994 	.get_acl = v9fs_iop_get_acl,
995 };
996 
997 const struct inode_operations v9fs_symlink_inode_operations_dotl = {
998 	.get_link = v9fs_vfs_get_link_dotl,
999 	.getattr = v9fs_vfs_getattr_dotl,
1000 	.setattr = v9fs_vfs_setattr_dotl,
1001 	.listxattr = v9fs_listxattr,
1002 };
1003