xref: /linux/fs/9p/vfs_inode_dotl.c (revision 3f41368fbfe1b3d5922d317fe1a0a0cab6846802)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * This file contains vfs inode ops for the 9P2000.L 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 #include <linux/module.h>
10 #include <linux/errno.h>
11 #include <linux/fs.h>
12 #include <linux/file.h>
13 #include <linux/pagemap.h>
14 #include <linux/stat.h>
15 #include <linux/string.h>
16 #include <linux/namei.h>
17 #include <linux/sched.h>
18 #include <linux/slab.h>
19 #include <linux/xattr.h>
20 #include <linux/posix_acl.h>
21 #include <net/9p/9p.h>
22 #include <net/9p/client.h>
23 
24 #include "v9fs.h"
25 #include "v9fs_vfs.h"
26 #include "fid.h"
27 #include "cache.h"
28 #include "xattr.h"
29 #include "acl.h"
30 
31 static int
32 v9fs_vfs_mknod_dotl(struct mnt_idmap *idmap, struct inode *dir,
33 		    struct dentry *dentry, umode_t omode, dev_t rdev);
34 
35 /**
36  * v9fs_get_fsgid_for_create - Helper function to get the gid for a new object
37  * @dir_inode: The directory inode
38  *
39  * Helper function to get the gid for creating a
40  * new file system object. This checks the S_ISGID to determine the owning
41  * group of the new file system object.
42  */
43 
44 static kgid_t v9fs_get_fsgid_for_create(struct inode *dir_inode)
45 {
46 	BUG_ON(dir_inode == NULL);
47 
48 	if (dir_inode->i_mode & S_ISGID) {
49 		/* set_gid bit is set.*/
50 		return dir_inode->i_gid;
51 	}
52 	return current_fsgid();
53 }
54 
55 
56 
57 struct inode *
58 v9fs_fid_iget_dotl(struct super_block *sb, struct p9_fid *fid, bool new)
59 {
60 	int retval;
61 	struct inode *inode;
62 	struct p9_stat_dotl *st;
63 	struct v9fs_session_info *v9ses = sb->s_fs_info;
64 
65 	inode = iget_locked(sb, QID2INO(&fid->qid));
66 	if (unlikely(!inode))
67 		return ERR_PTR(-ENOMEM);
68 	if (!(inode->i_state & I_NEW)) {
69 		if (!new) {
70 			goto done;
71 		} else { /* deal with race condition in inode number reuse */
72 			p9_debug(P9_DEBUG_ERROR, "WARNING: Inode collision %lx\n",
73 						inode->i_ino);
74 			iput(inode);
75 			remove_inode_hash(inode);
76 			inode = iget_locked(sb, QID2INO(&fid->qid));
77 			WARN_ON(!(inode->i_state & I_NEW));
78 		}
79 	}
80 
81 	/*
82 	 * initialize the inode with the stat info
83 	 * FIXME!! we may need support for stale inodes
84 	 * later.
85 	 */
86 	st = p9_client_getattr_dotl(fid, P9_STATS_BASIC | P9_STATS_GEN);
87 	if (IS_ERR(st)) {
88 		retval = PTR_ERR(st);
89 		goto error;
90 	}
91 
92 	retval = v9fs_init_inode(v9ses, inode, &fid->qid,
93 				 st->st_mode, new_decode_dev(st->st_rdev));
94 	v9fs_stat2inode_dotl(st, inode, 0);
95 	kfree(st);
96 	if (retval)
97 		goto error;
98 
99 	v9fs_set_netfs_context(inode);
100 	v9fs_cache_inode_get_cookie(inode);
101 	retval = v9fs_get_acl(inode, fid);
102 	if (retval)
103 		goto error;
104 
105 	unlock_new_inode(inode);
106 done:
107 	return inode;
108 error:
109 	iget_failed(inode);
110 	return ERR_PTR(retval);
111 }
112 
113 struct dotl_openflag_map {
114 	int open_flag;
115 	int dotl_flag;
116 };
117 
118 static int v9fs_mapped_dotl_flags(int flags)
119 {
120 	int i;
121 	int rflags = 0;
122 	struct dotl_openflag_map dotl_oflag_map[] = {
123 		{ O_CREAT,	P9_DOTL_CREATE },
124 		{ O_EXCL,	P9_DOTL_EXCL },
125 		{ O_NOCTTY,	P9_DOTL_NOCTTY },
126 		{ O_APPEND,	P9_DOTL_APPEND },
127 		{ O_NONBLOCK,	P9_DOTL_NONBLOCK },
128 		{ O_DSYNC,	P9_DOTL_DSYNC },
129 		{ FASYNC,	P9_DOTL_FASYNC },
130 		{ O_DIRECT,	P9_DOTL_DIRECT },
131 		{ O_LARGEFILE,	P9_DOTL_LARGEFILE },
132 		{ O_DIRECTORY,	P9_DOTL_DIRECTORY },
133 		{ O_NOFOLLOW,	P9_DOTL_NOFOLLOW },
134 		{ O_NOATIME,	P9_DOTL_NOATIME },
135 		{ O_CLOEXEC,	P9_DOTL_CLOEXEC },
136 		{ O_SYNC,	P9_DOTL_SYNC},
137 	};
138 	for (i = 0; i < ARRAY_SIZE(dotl_oflag_map); i++) {
139 		if (flags & dotl_oflag_map[i].open_flag)
140 			rflags |= dotl_oflag_map[i].dotl_flag;
141 	}
142 	return rflags;
143 }
144 
145 /**
146  * v9fs_open_to_dotl_flags- convert Linux specific open flags to
147  * plan 9 open flag.
148  * @flags: flags to convert
149  */
150 int v9fs_open_to_dotl_flags(int flags)
151 {
152 	int rflags = 0;
153 
154 	/*
155 	 * We have same bits for P9_DOTL_READONLY, P9_DOTL_WRONLY
156 	 * and P9_DOTL_NOACCESS
157 	 */
158 	rflags |= flags & O_ACCMODE;
159 	rflags |= v9fs_mapped_dotl_flags(flags);
160 
161 	return rflags;
162 }
163 
164 /**
165  * v9fs_vfs_create_dotl - VFS hook to create files for 9P2000.L protocol.
166  * @idmap: The user namespace of the mount
167  * @dir: directory inode that is being created
168  * @dentry:  dentry that is being deleted
169  * @omode: create permissions
170  * @excl: True if the file must not yet exist
171  *
172  */
173 static int
174 v9fs_vfs_create_dotl(struct mnt_idmap *idmap, struct inode *dir,
175 		     struct dentry *dentry, umode_t omode, bool excl)
176 {
177 	return v9fs_vfs_mknod_dotl(idmap, dir, dentry, omode, 0);
178 }
179 
180 static int
181 v9fs_vfs_atomic_open_dotl(struct inode *dir, struct dentry *dentry,
182 			  struct file *file, unsigned int flags, umode_t omode)
183 {
184 	int err = 0;
185 	kgid_t gid;
186 	umode_t mode;
187 	int p9_omode = v9fs_open_to_dotl_flags(flags);
188 	const unsigned char *name = NULL;
189 	struct p9_qid qid;
190 	struct inode *inode;
191 	struct p9_fid *fid = NULL;
192 	struct p9_fid *dfid = NULL, *ofid = NULL;
193 	struct v9fs_session_info *v9ses;
194 	struct posix_acl *pacl = NULL, *dacl = NULL;
195 	struct dentry *res = NULL;
196 
197 	if (d_in_lookup(dentry)) {
198 		res = v9fs_vfs_lookup(dir, dentry, 0);
199 		if (IS_ERR(res))
200 			return PTR_ERR(res);
201 
202 		if (res)
203 			dentry = res;
204 	}
205 
206 	/* Only creates */
207 	if (!(flags & O_CREAT) || d_really_is_positive(dentry))
208 		return	finish_no_open(file, res);
209 
210 	v9ses = v9fs_inode2v9ses(dir);
211 
212 	name = dentry->d_name.name;
213 	p9_debug(P9_DEBUG_VFS, "name:%s flags:0x%x mode:0x%x\n",
214 		 name, flags, omode);
215 
216 	dfid = v9fs_parent_fid(dentry);
217 	if (IS_ERR(dfid)) {
218 		err = PTR_ERR(dfid);
219 		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
220 		goto out;
221 	}
222 
223 	/* clone a fid to use for creation */
224 	ofid = clone_fid(dfid);
225 	if (IS_ERR(ofid)) {
226 		err = PTR_ERR(ofid);
227 		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
228 		goto out;
229 	}
230 
231 	gid = v9fs_get_fsgid_for_create(dir);
232 
233 	mode = omode;
234 	/* Update mode based on ACL value */
235 	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
236 	if (err) {
237 		p9_debug(P9_DEBUG_VFS, "Failed to get acl values in create %d\n",
238 			 err);
239 		goto out;
240 	}
241 
242 	if ((v9ses->cache & CACHE_WRITEBACK) && (p9_omode & P9_OWRITE)) {
243 		p9_omode = (p9_omode & ~P9_OWRITE) | P9_ORDWR;
244 		p9_debug(P9_DEBUG_CACHE,
245 			"write-only file with writeback enabled, creating w/ O_RDWR\n");
246 	}
247 	err = p9_client_create_dotl(ofid, name, p9_omode, mode, gid, &qid);
248 	if (err < 0) {
249 		p9_debug(P9_DEBUG_VFS, "p9_client_open_dotl failed in create %d\n",
250 			 err);
251 		goto out;
252 	}
253 	v9fs_invalidate_inode_attr(dir);
254 
255 	/* instantiate inode and assign the unopened fid to the dentry */
256 	fid = p9_client_walk(dfid, 1, &name, 1);
257 	if (IS_ERR(fid)) {
258 		err = PTR_ERR(fid);
259 		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
260 		goto out;
261 	}
262 	inode = v9fs_fid_iget_dotl(dir->i_sb, fid, true);
263 	if (IS_ERR(inode)) {
264 		err = PTR_ERR(inode);
265 		p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n", err);
266 		goto out;
267 	}
268 	/* Now set the ACL based on the default value */
269 	v9fs_set_create_acl(inode, fid, dacl, pacl);
270 
271 	v9fs_fid_add(dentry, &fid);
272 	d_instantiate(dentry, inode);
273 
274 	/* Since we are opening a file, assign the open fid to the file */
275 	err = finish_open(file, dentry, generic_file_open);
276 	if (err)
277 		goto out;
278 	file->private_data = ofid;
279 #ifdef CONFIG_9P_FSCACHE
280 	if (v9ses->cache & CACHE_FSCACHE) {
281 		struct v9fs_inode *v9inode = V9FS_I(inode);
282 		fscache_use_cookie(v9fs_inode_cookie(v9inode),
283 				   file->f_mode & FMODE_WRITE);
284 	}
285 #endif
286 	v9fs_fid_add_modes(ofid, v9ses->flags, v9ses->cache, flags);
287 	v9fs_open_fid_add(inode, &ofid);
288 	file->f_mode |= FMODE_CREATED;
289 out:
290 	p9_fid_put(dfid);
291 	p9_fid_put(ofid);
292 	p9_fid_put(fid);
293 	v9fs_put_acl(dacl, pacl);
294 	dput(res);
295 	return err;
296 }
297 
298 /**
299  * v9fs_vfs_mkdir_dotl - VFS mkdir hook to create a directory
300  * @idmap: The idmap of the mount
301  * @dir:  inode that is being unlinked
302  * @dentry: dentry that is being unlinked
303  * @omode: mode for new directory
304  *
305  */
306 
307 static int v9fs_vfs_mkdir_dotl(struct mnt_idmap *idmap,
308 			       struct inode *dir, struct dentry *dentry,
309 			       umode_t omode)
310 {
311 	int err;
312 	struct p9_fid *fid = NULL, *dfid = NULL;
313 	kgid_t gid;
314 	const unsigned char *name;
315 	umode_t mode;
316 	struct inode *inode;
317 	struct p9_qid qid;
318 	struct posix_acl *dacl = NULL, *pacl = NULL;
319 
320 	p9_debug(P9_DEBUG_VFS, "name %pd\n", dentry);
321 
322 	omode |= S_IFDIR;
323 	if (dir->i_mode & S_ISGID)
324 		omode |= S_ISGID;
325 
326 	dfid = v9fs_parent_fid(dentry);
327 	if (IS_ERR(dfid)) {
328 		err = PTR_ERR(dfid);
329 		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
330 		goto error;
331 	}
332 
333 	gid = v9fs_get_fsgid_for_create(dir);
334 	mode = omode;
335 	/* Update mode based on ACL value */
336 	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
337 	if (err) {
338 		p9_debug(P9_DEBUG_VFS, "Failed to get acl values in mkdir %d\n",
339 			 err);
340 		goto error;
341 	}
342 	name = dentry->d_name.name;
343 	err = p9_client_mkdir_dotl(dfid, name, mode, gid, &qid);
344 	if (err < 0)
345 		goto error;
346 	fid = p9_client_walk(dfid, 1, &name, 1);
347 	if (IS_ERR(fid)) {
348 		err = PTR_ERR(fid);
349 		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
350 			 err);
351 		goto error;
352 	}
353 
354 	/* instantiate inode and assign the unopened fid to the dentry */
355 	inode = v9fs_fid_iget_dotl(dir->i_sb, fid, true);
356 	if (IS_ERR(inode)) {
357 		err = PTR_ERR(inode);
358 		p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n",
359 			 err);
360 		goto error;
361 	}
362 	v9fs_fid_add(dentry, &fid);
363 	v9fs_set_create_acl(inode, fid, dacl, pacl);
364 	d_instantiate(dentry, inode);
365 	err = 0;
366 	inc_nlink(dir);
367 	v9fs_invalidate_inode_attr(dir);
368 error:
369 	p9_fid_put(fid);
370 	v9fs_put_acl(dacl, pacl);
371 	p9_fid_put(dfid);
372 	return err;
373 }
374 
375 static int
376 v9fs_vfs_getattr_dotl(struct mnt_idmap *idmap,
377 		      const struct path *path, struct kstat *stat,
378 		      u32 request_mask, unsigned int flags)
379 {
380 	struct dentry *dentry = path->dentry;
381 	struct v9fs_session_info *v9ses;
382 	struct p9_fid *fid;
383 	struct inode *inode = d_inode(dentry);
384 	struct p9_stat_dotl *st;
385 
386 	p9_debug(P9_DEBUG_VFS, "dentry: %p\n", dentry);
387 	v9ses = v9fs_dentry2v9ses(dentry);
388 	if (v9ses->cache & (CACHE_META|CACHE_LOOSE)) {
389 		generic_fillattr(&nop_mnt_idmap, request_mask, inode, stat);
390 		return 0;
391 	} else if (v9ses->cache) {
392 		if (S_ISREG(inode->i_mode)) {
393 			int retval = filemap_fdatawrite(inode->i_mapping);
394 
395 			if (retval)
396 				p9_debug(P9_DEBUG_ERROR,
397 				    "flushing writeback during getattr returned %d\n", retval);
398 		}
399 	}
400 	fid = v9fs_fid_lookup(dentry);
401 	if (IS_ERR(fid))
402 		return PTR_ERR(fid);
403 
404 	/* Ask for all the fields in stat structure. Server will return
405 	 * whatever it supports
406 	 */
407 
408 	st = p9_client_getattr_dotl(fid, P9_STATS_ALL);
409 	p9_fid_put(fid);
410 	if (IS_ERR(st))
411 		return PTR_ERR(st);
412 
413 	v9fs_stat2inode_dotl(st, d_inode(dentry), 0);
414 	generic_fillattr(&nop_mnt_idmap, request_mask, d_inode(dentry), stat);
415 	/* Change block size to what the server returned */
416 	stat->blksize = st->st_blksize;
417 
418 	kfree(st);
419 	return 0;
420 }
421 
422 /*
423  * Attribute flags.
424  */
425 #define P9_ATTR_MODE		(1 << 0)
426 #define P9_ATTR_UID		(1 << 1)
427 #define P9_ATTR_GID		(1 << 2)
428 #define P9_ATTR_SIZE		(1 << 3)
429 #define P9_ATTR_ATIME		(1 << 4)
430 #define P9_ATTR_MTIME		(1 << 5)
431 #define P9_ATTR_CTIME		(1 << 6)
432 #define P9_ATTR_ATIME_SET	(1 << 7)
433 #define P9_ATTR_MTIME_SET	(1 << 8)
434 
435 struct dotl_iattr_map {
436 	int iattr_valid;
437 	int p9_iattr_valid;
438 };
439 
440 static int v9fs_mapped_iattr_valid(int iattr_valid)
441 {
442 	int i;
443 	int p9_iattr_valid = 0;
444 	struct dotl_iattr_map dotl_iattr_map[] = {
445 		{ ATTR_MODE,		P9_ATTR_MODE },
446 		{ ATTR_UID,		P9_ATTR_UID },
447 		{ ATTR_GID,		P9_ATTR_GID },
448 		{ ATTR_SIZE,		P9_ATTR_SIZE },
449 		{ ATTR_ATIME,		P9_ATTR_ATIME },
450 		{ ATTR_MTIME,		P9_ATTR_MTIME },
451 		{ ATTR_CTIME,		P9_ATTR_CTIME },
452 		{ ATTR_ATIME_SET,	P9_ATTR_ATIME_SET },
453 		{ ATTR_MTIME_SET,	P9_ATTR_MTIME_SET },
454 	};
455 	for (i = 0; i < ARRAY_SIZE(dotl_iattr_map); i++) {
456 		if (iattr_valid & dotl_iattr_map[i].iattr_valid)
457 			p9_iattr_valid |= dotl_iattr_map[i].p9_iattr_valid;
458 	}
459 	return p9_iattr_valid;
460 }
461 
462 /**
463  * v9fs_vfs_setattr_dotl - set file metadata
464  * @idmap: idmap of the mount
465  * @dentry: file whose metadata to set
466  * @iattr: metadata assignment structure
467  *
468  */
469 
470 int v9fs_vfs_setattr_dotl(struct mnt_idmap *idmap,
471 			  struct dentry *dentry, struct iattr *iattr)
472 {
473 	int retval, use_dentry = 0;
474 	struct inode *inode = d_inode(dentry);
475 	struct v9fs_session_info __maybe_unused *v9ses;
476 	struct p9_fid *fid = NULL;
477 	struct p9_iattr_dotl p9attr = {
478 		.uid = INVALID_UID,
479 		.gid = INVALID_GID,
480 	};
481 
482 	p9_debug(P9_DEBUG_VFS, "\n");
483 
484 	retval = setattr_prepare(&nop_mnt_idmap, dentry, iattr);
485 	if (retval)
486 		return retval;
487 
488 	v9ses = v9fs_dentry2v9ses(dentry);
489 
490 	p9attr.valid = v9fs_mapped_iattr_valid(iattr->ia_valid);
491 	if (iattr->ia_valid & ATTR_MODE)
492 		p9attr.mode = iattr->ia_mode;
493 	if (iattr->ia_valid & ATTR_UID)
494 		p9attr.uid = iattr->ia_uid;
495 	if (iattr->ia_valid & ATTR_GID)
496 		p9attr.gid = iattr->ia_gid;
497 	if (iattr->ia_valid & ATTR_SIZE)
498 		p9attr.size = iattr->ia_size;
499 	if (iattr->ia_valid & ATTR_ATIME_SET) {
500 		p9attr.atime_sec = iattr->ia_atime.tv_sec;
501 		p9attr.atime_nsec = iattr->ia_atime.tv_nsec;
502 	}
503 	if (iattr->ia_valid & ATTR_MTIME_SET) {
504 		p9attr.mtime_sec = iattr->ia_mtime.tv_sec;
505 		p9attr.mtime_nsec = iattr->ia_mtime.tv_nsec;
506 	}
507 
508 	if (iattr->ia_valid & ATTR_FILE) {
509 		fid = iattr->ia_file->private_data;
510 		WARN_ON(!fid);
511 	}
512 	if (!fid) {
513 		fid = v9fs_fid_lookup(dentry);
514 		use_dentry = 1;
515 	}
516 	if (IS_ERR(fid))
517 		return PTR_ERR(fid);
518 
519 	/* Write all dirty data */
520 	if (S_ISREG(inode->i_mode)) {
521 		retval = filemap_fdatawrite(inode->i_mapping);
522 		if (retval < 0)
523 			p9_debug(P9_DEBUG_ERROR,
524 			    "Flushing file prior to setattr failed: %d\n", retval);
525 	}
526 
527 	retval = p9_client_setattr(fid, &p9attr);
528 	if (retval < 0) {
529 		if (use_dentry)
530 			p9_fid_put(fid);
531 		return retval;
532 	}
533 
534 	if ((iattr->ia_valid & ATTR_SIZE) && iattr->ia_size !=
535 		 i_size_read(inode)) {
536 		truncate_setsize(inode, iattr->ia_size);
537 		netfs_resize_file(netfs_inode(inode), iattr->ia_size, true);
538 
539 #ifdef CONFIG_9P_FSCACHE
540 		if (v9ses->cache & CACHE_FSCACHE)
541 			fscache_resize_cookie(v9fs_inode_cookie(V9FS_I(inode)),
542 				iattr->ia_size);
543 #endif
544 	}
545 
546 	v9fs_invalidate_inode_attr(inode);
547 	setattr_copy(&nop_mnt_idmap, inode, iattr);
548 	mark_inode_dirty(inode);
549 	if (iattr->ia_valid & ATTR_MODE) {
550 		/* We also want to update ACL when we update mode bits */
551 		retval = v9fs_acl_chmod(inode, fid);
552 		if (retval < 0) {
553 			if (use_dentry)
554 				p9_fid_put(fid);
555 			return retval;
556 		}
557 	}
558 	if (use_dentry)
559 		p9_fid_put(fid);
560 
561 	return 0;
562 }
563 
564 /**
565  * v9fs_stat2inode_dotl - populate an inode structure with stat info
566  * @stat: stat structure
567  * @inode: inode to populate
568  * @flags: ctrl flags (e.g. V9FS_STAT2INODE_KEEP_ISIZE)
569  *
570  */
571 
572 void
573 v9fs_stat2inode_dotl(struct p9_stat_dotl *stat, struct inode *inode,
574 		      unsigned int flags)
575 {
576 	umode_t mode;
577 	struct v9fs_inode *v9inode = V9FS_I(inode);
578 
579 	if ((stat->st_result_mask & P9_STATS_BASIC) == P9_STATS_BASIC) {
580 		inode_set_atime(inode, stat->st_atime_sec,
581 				stat->st_atime_nsec);
582 		inode_set_mtime(inode, stat->st_mtime_sec,
583 				stat->st_mtime_nsec);
584 		inode_set_ctime(inode, stat->st_ctime_sec,
585 				stat->st_ctime_nsec);
586 		inode->i_uid = stat->st_uid;
587 		inode->i_gid = stat->st_gid;
588 		set_nlink(inode, stat->st_nlink);
589 
590 		mode = stat->st_mode & S_IALLUGO;
591 		mode |= inode->i_mode & ~S_IALLUGO;
592 		inode->i_mode = mode;
593 
594 		v9inode->netfs.remote_i_size = stat->st_size;
595 		if (!(flags & V9FS_STAT2INODE_KEEP_ISIZE))
596 			v9fs_i_size_write(inode, stat->st_size);
597 		inode->i_blocks = stat->st_blocks;
598 	} else {
599 		if (stat->st_result_mask & P9_STATS_ATIME) {
600 			inode_set_atime(inode, stat->st_atime_sec,
601 					stat->st_atime_nsec);
602 		}
603 		if (stat->st_result_mask & P9_STATS_MTIME) {
604 			inode_set_mtime(inode, stat->st_mtime_sec,
605 					stat->st_mtime_nsec);
606 		}
607 		if (stat->st_result_mask & P9_STATS_CTIME) {
608 			inode_set_ctime(inode, stat->st_ctime_sec,
609 					stat->st_ctime_nsec);
610 		}
611 		if (stat->st_result_mask & P9_STATS_UID)
612 			inode->i_uid = stat->st_uid;
613 		if (stat->st_result_mask & P9_STATS_GID)
614 			inode->i_gid = stat->st_gid;
615 		if (stat->st_result_mask & P9_STATS_NLINK)
616 			set_nlink(inode, stat->st_nlink);
617 		if (stat->st_result_mask & P9_STATS_MODE) {
618 			mode = stat->st_mode & S_IALLUGO;
619 			mode |= inode->i_mode & ~S_IALLUGO;
620 			inode->i_mode = mode;
621 		}
622 		if (!(flags & V9FS_STAT2INODE_KEEP_ISIZE) &&
623 		    stat->st_result_mask & P9_STATS_SIZE) {
624 			v9inode->netfs.remote_i_size = stat->st_size;
625 			v9fs_i_size_write(inode, stat->st_size);
626 		}
627 		if (stat->st_result_mask & P9_STATS_BLOCKS)
628 			inode->i_blocks = stat->st_blocks;
629 	}
630 	if (stat->st_result_mask & P9_STATS_GEN)
631 		inode->i_generation = stat->st_gen;
632 
633 	/* Currently we don't support P9_STATS_BTIME and P9_STATS_DATA_VERSION
634 	 * because the inode structure does not have fields for them.
635 	 */
636 	v9inode->cache_validity &= ~V9FS_INO_INVALID_ATTR;
637 }
638 
639 static int
640 v9fs_vfs_symlink_dotl(struct mnt_idmap *idmap, struct inode *dir,
641 		      struct dentry *dentry, const char *symname)
642 {
643 	int err;
644 	kgid_t gid;
645 	const unsigned char *name;
646 	struct p9_qid qid;
647 	struct p9_fid *dfid;
648 	struct p9_fid *fid = NULL;
649 
650 	name = dentry->d_name.name;
651 	p9_debug(P9_DEBUG_VFS, "%lu,%s,%s\n", dir->i_ino, name, symname);
652 
653 	dfid = v9fs_parent_fid(dentry);
654 	if (IS_ERR(dfid)) {
655 		err = PTR_ERR(dfid);
656 		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
657 		return err;
658 	}
659 
660 	gid = v9fs_get_fsgid_for_create(dir);
661 
662 	/* Server doesn't alter fid on TSYMLINK. Hence no need to clone it. */
663 	err = p9_client_symlink(dfid, name, symname, gid, &qid);
664 
665 	if (err < 0) {
666 		p9_debug(P9_DEBUG_VFS, "p9_client_symlink failed %d\n", err);
667 		goto error;
668 	}
669 
670 	v9fs_invalidate_inode_attr(dir);
671 
672 error:
673 	p9_fid_put(fid);
674 	p9_fid_put(dfid);
675 	return err;
676 }
677 
678 /**
679  * v9fs_vfs_link_dotl - create a hardlink for dotl
680  * @old_dentry: dentry for file to link to
681  * @dir: inode destination for new link
682  * @dentry: dentry for link
683  *
684  */
685 
686 static int
687 v9fs_vfs_link_dotl(struct dentry *old_dentry, struct inode *dir,
688 		struct dentry *dentry)
689 {
690 	int err;
691 	struct p9_fid *dfid, *oldfid;
692 	struct v9fs_session_info *v9ses;
693 
694 	p9_debug(P9_DEBUG_VFS, "dir ino: %lu, old_name: %pd, new_name: %pd\n",
695 		 dir->i_ino, old_dentry, dentry);
696 
697 	v9ses = v9fs_inode2v9ses(dir);
698 	dfid = v9fs_parent_fid(dentry);
699 	if (IS_ERR(dfid))
700 		return PTR_ERR(dfid);
701 
702 	oldfid = v9fs_fid_lookup(old_dentry);
703 	if (IS_ERR(oldfid)) {
704 		p9_fid_put(dfid);
705 		return PTR_ERR(oldfid);
706 	}
707 
708 	err = p9_client_link(dfid, oldfid, dentry->d_name.name);
709 
710 	p9_fid_put(dfid);
711 	p9_fid_put(oldfid);
712 	if (err < 0) {
713 		p9_debug(P9_DEBUG_VFS, "p9_client_link failed %d\n", err);
714 		return err;
715 	}
716 
717 	v9fs_invalidate_inode_attr(dir);
718 	if (v9ses->cache & (CACHE_META|CACHE_LOOSE)) {
719 		/* Get the latest stat info from server. */
720 		struct p9_fid *fid;
721 
722 		fid = v9fs_fid_lookup(old_dentry);
723 		if (IS_ERR(fid))
724 			return PTR_ERR(fid);
725 
726 		v9fs_refresh_inode_dotl(fid, d_inode(old_dentry));
727 		p9_fid_put(fid);
728 	}
729 	ihold(d_inode(old_dentry));
730 	d_instantiate(dentry, d_inode(old_dentry));
731 
732 	return err;
733 }
734 
735 /**
736  * v9fs_vfs_mknod_dotl - create a special file
737  * @idmap: The idmap of the mount
738  * @dir: inode destination for new link
739  * @dentry: dentry for file
740  * @omode: mode for creation
741  * @rdev: device associated with special file
742  *
743  */
744 static int
745 v9fs_vfs_mknod_dotl(struct mnt_idmap *idmap, struct inode *dir,
746 		    struct dentry *dentry, umode_t omode, dev_t rdev)
747 {
748 	int err;
749 	kgid_t gid;
750 	const unsigned char *name;
751 	umode_t mode;
752 	struct p9_fid *fid = NULL, *dfid = NULL;
753 	struct inode *inode;
754 	struct p9_qid qid;
755 	struct posix_acl *dacl = NULL, *pacl = NULL;
756 
757 	p9_debug(P9_DEBUG_VFS, " %lu,%pd mode: %x MAJOR: %u MINOR: %u\n",
758 		 dir->i_ino, dentry, omode,
759 		 MAJOR(rdev), MINOR(rdev));
760 
761 	dfid = v9fs_parent_fid(dentry);
762 	if (IS_ERR(dfid)) {
763 		err = PTR_ERR(dfid);
764 		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
765 		goto error;
766 	}
767 
768 	gid = v9fs_get_fsgid_for_create(dir);
769 	mode = omode;
770 	/* Update mode based on ACL value */
771 	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
772 	if (err) {
773 		p9_debug(P9_DEBUG_VFS, "Failed to get acl values in mknod %d\n",
774 			 err);
775 		goto error;
776 	}
777 	name = dentry->d_name.name;
778 
779 	err = p9_client_mknod_dotl(dfid, name, mode, rdev, gid, &qid);
780 	if (err < 0)
781 		goto error;
782 
783 	v9fs_invalidate_inode_attr(dir);
784 	fid = p9_client_walk(dfid, 1, &name, 1);
785 	if (IS_ERR(fid)) {
786 		err = PTR_ERR(fid);
787 		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
788 			 err);
789 		goto error;
790 	}
791 	inode = v9fs_fid_iget_dotl(dir->i_sb, fid, true);
792 	if (IS_ERR(inode)) {
793 		err = PTR_ERR(inode);
794 		p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n",
795 			 err);
796 		goto error;
797 	}
798 	v9fs_set_create_acl(inode, fid, dacl, pacl);
799 	v9fs_fid_add(dentry, &fid);
800 	d_instantiate(dentry, inode);
801 	err = 0;
802 error:
803 	p9_fid_put(fid);
804 	v9fs_put_acl(dacl, pacl);
805 	p9_fid_put(dfid);
806 
807 	return err;
808 }
809 
810 /**
811  * v9fs_vfs_get_link_dotl - follow a symlink path
812  * @dentry: dentry for symlink
813  * @inode: inode for symlink
814  * @done: destructor for return value
815  */
816 
817 static const char *
818 v9fs_vfs_get_link_dotl(struct dentry *dentry,
819 		       struct inode *inode,
820 		       struct delayed_call *done)
821 {
822 	struct p9_fid *fid;
823 	char *target;
824 	int retval;
825 
826 	if (!dentry)
827 		return ERR_PTR(-ECHILD);
828 
829 	p9_debug(P9_DEBUG_VFS, "%pd\n", dentry);
830 
831 	fid = v9fs_fid_lookup(dentry);
832 	if (IS_ERR(fid))
833 		return ERR_CAST(fid);
834 	retval = p9_client_readlink(fid, &target);
835 	p9_fid_put(fid);
836 	if (retval)
837 		return ERR_PTR(retval);
838 	set_delayed_call(done, kfree_link, target);
839 	return target;
840 }
841 
842 int v9fs_refresh_inode_dotl(struct p9_fid *fid, struct inode *inode)
843 {
844 	struct p9_stat_dotl *st;
845 	struct v9fs_session_info *v9ses;
846 	unsigned int flags;
847 
848 	v9ses = v9fs_inode2v9ses(inode);
849 	st = p9_client_getattr_dotl(fid, P9_STATS_ALL);
850 	if (IS_ERR(st))
851 		return PTR_ERR(st);
852 	/*
853 	 * Don't update inode if the file type is different
854 	 */
855 	if (inode_wrong_type(inode, st->st_mode))
856 		goto out;
857 
858 	/*
859 	 * We don't want to refresh inode->i_size,
860 	 * because we may have cached data
861 	 */
862 	flags = (v9ses->cache & CACHE_LOOSE) ?
863 		V9FS_STAT2INODE_KEEP_ISIZE : 0;
864 	v9fs_stat2inode_dotl(st, inode, flags);
865 out:
866 	kfree(st);
867 	return 0;
868 }
869 
870 const struct inode_operations v9fs_dir_inode_operations_dotl = {
871 	.create = v9fs_vfs_create_dotl,
872 	.atomic_open = v9fs_vfs_atomic_open_dotl,
873 	.lookup = v9fs_vfs_lookup,
874 	.link = v9fs_vfs_link_dotl,
875 	.symlink = v9fs_vfs_symlink_dotl,
876 	.unlink = v9fs_vfs_unlink,
877 	.mkdir = v9fs_vfs_mkdir_dotl,
878 	.rmdir = v9fs_vfs_rmdir,
879 	.mknod = v9fs_vfs_mknod_dotl,
880 	.rename = v9fs_vfs_rename,
881 	.getattr = v9fs_vfs_getattr_dotl,
882 	.setattr = v9fs_vfs_setattr_dotl,
883 	.listxattr = v9fs_listxattr,
884 	.get_inode_acl = v9fs_iop_get_inode_acl,
885 	.get_acl = v9fs_iop_get_acl,
886 	.set_acl = v9fs_iop_set_acl,
887 };
888 
889 const struct inode_operations v9fs_file_inode_operations_dotl = {
890 	.getattr = v9fs_vfs_getattr_dotl,
891 	.setattr = v9fs_vfs_setattr_dotl,
892 	.listxattr = v9fs_listxattr,
893 	.get_inode_acl = v9fs_iop_get_inode_acl,
894 	.get_acl = v9fs_iop_get_acl,
895 	.set_acl = v9fs_iop_set_acl,
896 };
897 
898 const struct inode_operations v9fs_symlink_inode_operations_dotl = {
899 	.get_link = v9fs_vfs_get_link_dotl,
900 	.getattr = v9fs_vfs_getattr_dotl,
901 	.setattr = v9fs_vfs_setattr_dotl,
902 	.listxattr = v9fs_listxattr,
903 };
904