xref: /openbmc/linux/fs/9p/vfs_inode_dotl.c (revision 84b102f5)
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 inode *dir, struct dentry *dentry, umode_t omode,
37 		    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->i_mode & S_IFMT) != (st->st_mode & S_IFMT))
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 inode *dir, struct dentry *dentry, umode_t omode,
222 		bool excl)
223 {
224 	return v9fs_vfs_mknod_dotl(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 inode *dir,
371 			       struct dentry *dentry, umode_t omode)
372 {
373 	int err;
374 	struct v9fs_session_info *v9ses;
375 	struct p9_fid *fid = NULL, *dfid = NULL;
376 	kgid_t gid;
377 	const unsigned char *name;
378 	umode_t mode;
379 	struct inode *inode;
380 	struct p9_qid qid;
381 	struct posix_acl *dacl = NULL, *pacl = NULL;
382 
383 	p9_debug(P9_DEBUG_VFS, "name %pd\n", dentry);
384 	err = 0;
385 	v9ses = v9fs_inode2v9ses(dir);
386 
387 	omode |= S_IFDIR;
388 	if (dir->i_mode & S_ISGID)
389 		omode |= S_ISGID;
390 
391 	dfid = v9fs_parent_fid(dentry);
392 	if (IS_ERR(dfid)) {
393 		err = PTR_ERR(dfid);
394 		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
395 		dfid = NULL;
396 		goto error;
397 	}
398 
399 	gid = v9fs_get_fsgid_for_create(dir);
400 	mode = omode;
401 	/* Update mode based on ACL value */
402 	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
403 	if (err) {
404 		p9_debug(P9_DEBUG_VFS, "Failed to get acl values in mkdir %d\n",
405 			 err);
406 		goto error;
407 	}
408 	name = dentry->d_name.name;
409 	err = p9_client_mkdir_dotl(dfid, name, mode, gid, &qid);
410 	if (err < 0)
411 		goto error;
412 	fid = p9_client_walk(dfid, 1, &name, 1);
413 	if (IS_ERR(fid)) {
414 		err = PTR_ERR(fid);
415 		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
416 			 err);
417 		fid = NULL;
418 		goto error;
419 	}
420 
421 	/* instantiate inode and assign the unopened fid to the dentry */
422 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
423 		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
424 		if (IS_ERR(inode)) {
425 			err = PTR_ERR(inode);
426 			p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n",
427 				 err);
428 			goto error;
429 		}
430 		v9fs_fid_add(dentry, fid);
431 		v9fs_set_create_acl(inode, fid, dacl, pacl);
432 		d_instantiate(dentry, inode);
433 		fid = NULL;
434 		err = 0;
435 	} else {
436 		/*
437 		 * Not in cached mode. No need to populate
438 		 * inode with stat. We need to get an inode
439 		 * so that we can set the acl with dentry
440 		 */
441 		inode = v9fs_get_inode(dir->i_sb, mode, 0);
442 		if (IS_ERR(inode)) {
443 			err = PTR_ERR(inode);
444 			goto error;
445 		}
446 		v9fs_set_create_acl(inode, fid, dacl, pacl);
447 		d_instantiate(dentry, inode);
448 	}
449 	inc_nlink(dir);
450 	v9fs_invalidate_inode_attr(dir);
451 error:
452 	if (fid)
453 		p9_client_clunk(fid);
454 	v9fs_put_acl(dacl, pacl);
455 	p9_client_clunk(dfid);
456 	return err;
457 }
458 
459 static int
460 v9fs_vfs_getattr_dotl(const struct path *path, struct kstat *stat,
461 		 u32 request_mask, unsigned int flags)
462 {
463 	struct dentry *dentry = path->dentry;
464 	struct v9fs_session_info *v9ses;
465 	struct p9_fid *fid;
466 	struct p9_stat_dotl *st;
467 
468 	p9_debug(P9_DEBUG_VFS, "dentry: %p\n", dentry);
469 	v9ses = v9fs_dentry2v9ses(dentry);
470 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
471 		generic_fillattr(d_inode(dentry), stat);
472 		return 0;
473 	}
474 	fid = v9fs_fid_lookup(dentry);
475 	if (IS_ERR(fid))
476 		return PTR_ERR(fid);
477 
478 	/* Ask for all the fields in stat structure. Server will return
479 	 * whatever it supports
480 	 */
481 
482 	st = p9_client_getattr_dotl(fid, P9_STATS_ALL);
483 	p9_client_clunk(fid);
484 	if (IS_ERR(st))
485 		return PTR_ERR(st);
486 
487 	v9fs_stat2inode_dotl(st, d_inode(dentry), 0);
488 	generic_fillattr(d_inode(dentry), stat);
489 	/* Change block size to what the server returned */
490 	stat->blksize = st->st_blksize;
491 
492 	kfree(st);
493 	return 0;
494 }
495 
496 /*
497  * Attribute flags.
498  */
499 #define P9_ATTR_MODE		(1 << 0)
500 #define P9_ATTR_UID		(1 << 1)
501 #define P9_ATTR_GID		(1 << 2)
502 #define P9_ATTR_SIZE		(1 << 3)
503 #define P9_ATTR_ATIME		(1 << 4)
504 #define P9_ATTR_MTIME		(1 << 5)
505 #define P9_ATTR_CTIME		(1 << 6)
506 #define P9_ATTR_ATIME_SET	(1 << 7)
507 #define P9_ATTR_MTIME_SET	(1 << 8)
508 
509 struct dotl_iattr_map {
510 	int iattr_valid;
511 	int p9_iattr_valid;
512 };
513 
514 static int v9fs_mapped_iattr_valid(int iattr_valid)
515 {
516 	int i;
517 	int p9_iattr_valid = 0;
518 	struct dotl_iattr_map dotl_iattr_map[] = {
519 		{ ATTR_MODE,		P9_ATTR_MODE },
520 		{ ATTR_UID,		P9_ATTR_UID },
521 		{ ATTR_GID,		P9_ATTR_GID },
522 		{ ATTR_SIZE,		P9_ATTR_SIZE },
523 		{ ATTR_ATIME,		P9_ATTR_ATIME },
524 		{ ATTR_MTIME,		P9_ATTR_MTIME },
525 		{ ATTR_CTIME,		P9_ATTR_CTIME },
526 		{ ATTR_ATIME_SET,	P9_ATTR_ATIME_SET },
527 		{ ATTR_MTIME_SET,	P9_ATTR_MTIME_SET },
528 	};
529 	for (i = 0; i < ARRAY_SIZE(dotl_iattr_map); i++) {
530 		if (iattr_valid & dotl_iattr_map[i].iattr_valid)
531 			p9_iattr_valid |= dotl_iattr_map[i].p9_iattr_valid;
532 	}
533 	return p9_iattr_valid;
534 }
535 
536 /**
537  * v9fs_vfs_setattr_dotl - set file metadata
538  * @dentry: file whose metadata to set
539  * @iattr: metadata assignment structure
540  *
541  */
542 
543 int v9fs_vfs_setattr_dotl(struct dentry *dentry, struct iattr *iattr)
544 {
545 	int retval, use_dentry = 0;
546 	struct p9_fid *fid = NULL;
547 	struct p9_iattr_dotl p9attr;
548 	struct inode *inode = d_inode(dentry);
549 
550 	p9_debug(P9_DEBUG_VFS, "\n");
551 
552 	retval = setattr_prepare(dentry, iattr);
553 	if (retval)
554 		return retval;
555 
556 	p9attr.valid = v9fs_mapped_iattr_valid(iattr->ia_valid);
557 	p9attr.mode = iattr->ia_mode;
558 	p9attr.uid = iattr->ia_uid;
559 	p9attr.gid = iattr->ia_gid;
560 	p9attr.size = iattr->ia_size;
561 	p9attr.atime_sec = iattr->ia_atime.tv_sec;
562 	p9attr.atime_nsec = iattr->ia_atime.tv_nsec;
563 	p9attr.mtime_sec = iattr->ia_mtime.tv_sec;
564 	p9attr.mtime_nsec = iattr->ia_mtime.tv_nsec;
565 
566 	if (iattr->ia_valid & ATTR_FILE) {
567 		fid = iattr->ia_file->private_data;
568 		WARN_ON(!fid);
569 	}
570 	if (!fid) {
571 		fid = v9fs_fid_lookup(dentry);
572 		use_dentry = 1;
573 	}
574 	if (IS_ERR(fid))
575 		return PTR_ERR(fid);
576 
577 	/* Write all dirty data */
578 	if (S_ISREG(inode->i_mode))
579 		filemap_write_and_wait(inode->i_mapping);
580 
581 	retval = p9_client_setattr(fid, &p9attr);
582 	if (retval < 0) {
583 		if (use_dentry)
584 			p9_client_clunk(fid);
585 		return retval;
586 	}
587 
588 	if ((iattr->ia_valid & ATTR_SIZE) &&
589 	    iattr->ia_size != i_size_read(inode))
590 		truncate_setsize(inode, iattr->ia_size);
591 
592 	v9fs_invalidate_inode_attr(inode);
593 	setattr_copy(inode, iattr);
594 	mark_inode_dirty(inode);
595 	if (iattr->ia_valid & ATTR_MODE) {
596 		/* We also want to update ACL when we update mode bits */
597 		retval = v9fs_acl_chmod(inode, fid);
598 		if (retval < 0) {
599 			if (use_dentry)
600 				p9_client_clunk(fid);
601 			return retval;
602 		}
603 	}
604 	if (use_dentry)
605 		p9_client_clunk(fid);
606 
607 	return 0;
608 }
609 
610 /**
611  * v9fs_stat2inode_dotl - populate an inode structure with stat info
612  * @stat: stat structure
613  * @inode: inode to populate
614  * @flags: ctrl flags (e.g. V9FS_STAT2INODE_KEEP_ISIZE)
615  *
616  */
617 
618 void
619 v9fs_stat2inode_dotl(struct p9_stat_dotl *stat, struct inode *inode,
620 		      unsigned int flags)
621 {
622 	umode_t mode;
623 	struct v9fs_inode *v9inode = V9FS_I(inode);
624 
625 	if ((stat->st_result_mask & P9_STATS_BASIC) == P9_STATS_BASIC) {
626 		inode->i_atime.tv_sec = stat->st_atime_sec;
627 		inode->i_atime.tv_nsec = stat->st_atime_nsec;
628 		inode->i_mtime.tv_sec = stat->st_mtime_sec;
629 		inode->i_mtime.tv_nsec = stat->st_mtime_nsec;
630 		inode->i_ctime.tv_sec = stat->st_ctime_sec;
631 		inode->i_ctime.tv_nsec = stat->st_ctime_nsec;
632 		inode->i_uid = stat->st_uid;
633 		inode->i_gid = stat->st_gid;
634 		set_nlink(inode, stat->st_nlink);
635 
636 		mode = stat->st_mode & S_IALLUGO;
637 		mode |= inode->i_mode & ~S_IALLUGO;
638 		inode->i_mode = mode;
639 
640 		if (!(flags & V9FS_STAT2INODE_KEEP_ISIZE))
641 			v9fs_i_size_write(inode, stat->st_size);
642 		inode->i_blocks = stat->st_blocks;
643 	} else {
644 		if (stat->st_result_mask & P9_STATS_ATIME) {
645 			inode->i_atime.tv_sec = stat->st_atime_sec;
646 			inode->i_atime.tv_nsec = stat->st_atime_nsec;
647 		}
648 		if (stat->st_result_mask & P9_STATS_MTIME) {
649 			inode->i_mtime.tv_sec = stat->st_mtime_sec;
650 			inode->i_mtime.tv_nsec = stat->st_mtime_nsec;
651 		}
652 		if (stat->st_result_mask & P9_STATS_CTIME) {
653 			inode->i_ctime.tv_sec = stat->st_ctime_sec;
654 			inode->i_ctime.tv_nsec = stat->st_ctime_nsec;
655 		}
656 		if (stat->st_result_mask & P9_STATS_UID)
657 			inode->i_uid = stat->st_uid;
658 		if (stat->st_result_mask & P9_STATS_GID)
659 			inode->i_gid = stat->st_gid;
660 		if (stat->st_result_mask & P9_STATS_NLINK)
661 			set_nlink(inode, stat->st_nlink);
662 		if (stat->st_result_mask & P9_STATS_MODE) {
663 			inode->i_mode = stat->st_mode;
664 			if ((S_ISBLK(inode->i_mode)) ||
665 						(S_ISCHR(inode->i_mode)))
666 				init_special_inode(inode, inode->i_mode,
667 								inode->i_rdev);
668 		}
669 		if (stat->st_result_mask & P9_STATS_RDEV)
670 			inode->i_rdev = new_decode_dev(stat->st_rdev);
671 		if (!(flags & V9FS_STAT2INODE_KEEP_ISIZE) &&
672 		    stat->st_result_mask & P9_STATS_SIZE)
673 			v9fs_i_size_write(inode, stat->st_size);
674 		if (stat->st_result_mask & P9_STATS_BLOCKS)
675 			inode->i_blocks = stat->st_blocks;
676 	}
677 	if (stat->st_result_mask & P9_STATS_GEN)
678 		inode->i_generation = stat->st_gen;
679 
680 	/* Currently we don't support P9_STATS_BTIME and P9_STATS_DATA_VERSION
681 	 * because the inode structure does not have fields for them.
682 	 */
683 	v9inode->cache_validity &= ~V9FS_INO_INVALID_ATTR;
684 }
685 
686 static int
687 v9fs_vfs_symlink_dotl(struct inode *dir, struct dentry *dentry,
688 		const char *symname)
689 {
690 	int err;
691 	kgid_t gid;
692 	const unsigned char *name;
693 	struct p9_qid qid;
694 	struct inode *inode;
695 	struct p9_fid *dfid;
696 	struct p9_fid *fid = NULL;
697 	struct v9fs_session_info *v9ses;
698 
699 	name = dentry->d_name.name;
700 	p9_debug(P9_DEBUG_VFS, "%lu,%s,%s\n", dir->i_ino, name, symname);
701 	v9ses = v9fs_inode2v9ses(dir);
702 
703 	dfid = v9fs_parent_fid(dentry);
704 	if (IS_ERR(dfid)) {
705 		err = PTR_ERR(dfid);
706 		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
707 		return err;
708 	}
709 
710 	gid = v9fs_get_fsgid_for_create(dir);
711 
712 	/* Server doesn't alter fid on TSYMLINK. Hence no need to clone it. */
713 	err = p9_client_symlink(dfid, name, symname, gid, &qid);
714 
715 	if (err < 0) {
716 		p9_debug(P9_DEBUG_VFS, "p9_client_symlink failed %d\n", err);
717 		goto error;
718 	}
719 
720 	v9fs_invalidate_inode_attr(dir);
721 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
722 		/* Now walk from the parent so we can get an unopened fid. */
723 		fid = p9_client_walk(dfid, 1, &name, 1);
724 		if (IS_ERR(fid)) {
725 			err = PTR_ERR(fid);
726 			p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
727 				 err);
728 			fid = NULL;
729 			goto error;
730 		}
731 
732 		/* instantiate inode and assign the unopened fid to dentry */
733 		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
734 		if (IS_ERR(inode)) {
735 			err = PTR_ERR(inode);
736 			p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n",
737 				 err);
738 			goto error;
739 		}
740 		v9fs_fid_add(dentry, fid);
741 		d_instantiate(dentry, inode);
742 		fid = NULL;
743 		err = 0;
744 	} else {
745 		/* Not in cached mode. No need to populate inode with stat */
746 		inode = v9fs_get_inode(dir->i_sb, S_IFLNK, 0);
747 		if (IS_ERR(inode)) {
748 			err = PTR_ERR(inode);
749 			goto error;
750 		}
751 		d_instantiate(dentry, inode);
752 	}
753 
754 error:
755 	if (fid)
756 		p9_client_clunk(fid);
757 
758 	p9_client_clunk(dfid);
759 	return err;
760 }
761 
762 /**
763  * v9fs_vfs_link_dotl - create a hardlink for dotl
764  * @old_dentry: dentry for file to link to
765  * @dir: inode destination for new link
766  * @dentry: dentry for link
767  *
768  */
769 
770 static int
771 v9fs_vfs_link_dotl(struct dentry *old_dentry, struct inode *dir,
772 		struct dentry *dentry)
773 {
774 	int err;
775 	struct p9_fid *dfid, *oldfid;
776 	struct v9fs_session_info *v9ses;
777 
778 	p9_debug(P9_DEBUG_VFS, "dir ino: %lu, old_name: %pd, new_name: %pd\n",
779 		 dir->i_ino, old_dentry, dentry);
780 
781 	v9ses = v9fs_inode2v9ses(dir);
782 	dfid = v9fs_parent_fid(dentry);
783 	if (IS_ERR(dfid))
784 		return PTR_ERR(dfid);
785 
786 	oldfid = v9fs_fid_lookup(old_dentry);
787 	if (IS_ERR(oldfid)) {
788 		p9_client_clunk(dfid);
789 		return PTR_ERR(oldfid);
790 	}
791 
792 	err = p9_client_link(dfid, oldfid, dentry->d_name.name);
793 
794 	p9_client_clunk(dfid);
795 	p9_client_clunk(oldfid);
796 	if (err < 0) {
797 		p9_debug(P9_DEBUG_VFS, "p9_client_link failed %d\n", err);
798 		return err;
799 	}
800 
801 	v9fs_invalidate_inode_attr(dir);
802 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
803 		/* Get the latest stat info from server. */
804 		struct p9_fid *fid;
805 		fid = v9fs_fid_lookup(old_dentry);
806 		if (IS_ERR(fid))
807 			return PTR_ERR(fid);
808 
809 		v9fs_refresh_inode_dotl(fid, d_inode(old_dentry));
810 		p9_client_clunk(fid);
811 	}
812 	ihold(d_inode(old_dentry));
813 	d_instantiate(dentry, d_inode(old_dentry));
814 
815 	return err;
816 }
817 
818 /**
819  * v9fs_vfs_mknod_dotl - create a special file
820  * @dir: inode destination for new link
821  * @dentry: dentry for file
822  * @omode: mode for creation
823  * @rdev: device associated with special file
824  *
825  */
826 static int
827 v9fs_vfs_mknod_dotl(struct inode *dir, struct dentry *dentry, umode_t omode,
828 		dev_t rdev)
829 {
830 	int err;
831 	kgid_t gid;
832 	const unsigned char *name;
833 	umode_t mode;
834 	struct v9fs_session_info *v9ses;
835 	struct p9_fid *fid = NULL, *dfid = NULL;
836 	struct inode *inode;
837 	struct p9_qid qid;
838 	struct posix_acl *dacl = NULL, *pacl = NULL;
839 
840 	p9_debug(P9_DEBUG_VFS, " %lu,%pd mode: %hx MAJOR: %u MINOR: %u\n",
841 		 dir->i_ino, dentry, omode,
842 		 MAJOR(rdev), MINOR(rdev));
843 
844 	v9ses = v9fs_inode2v9ses(dir);
845 	dfid = v9fs_parent_fid(dentry);
846 	if (IS_ERR(dfid)) {
847 		err = PTR_ERR(dfid);
848 		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
849 		dfid = NULL;
850 		goto error;
851 	}
852 
853 	gid = v9fs_get_fsgid_for_create(dir);
854 	mode = omode;
855 	/* Update mode based on ACL value */
856 	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
857 	if (err) {
858 		p9_debug(P9_DEBUG_VFS, "Failed to get acl values in mknod %d\n",
859 			 err);
860 		goto error;
861 	}
862 	name = dentry->d_name.name;
863 
864 	err = p9_client_mknod_dotl(dfid, name, mode, rdev, gid, &qid);
865 	if (err < 0)
866 		goto error;
867 
868 	v9fs_invalidate_inode_attr(dir);
869 	fid = p9_client_walk(dfid, 1, &name, 1);
870 	if (IS_ERR(fid)) {
871 		err = PTR_ERR(fid);
872 		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
873 			 err);
874 		fid = NULL;
875 		goto error;
876 	}
877 
878 	/* instantiate inode and assign the unopened fid to the dentry */
879 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
880 		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
881 		if (IS_ERR(inode)) {
882 			err = PTR_ERR(inode);
883 			p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n",
884 				 err);
885 			goto error;
886 		}
887 		v9fs_set_create_acl(inode, fid, dacl, pacl);
888 		v9fs_fid_add(dentry, fid);
889 		d_instantiate(dentry, inode);
890 		fid = NULL;
891 		err = 0;
892 	} else {
893 		/*
894 		 * Not in cached mode. No need to populate inode with stat.
895 		 * socket syscall returns a fd, so we need instantiate
896 		 */
897 		inode = v9fs_get_inode(dir->i_sb, mode, rdev);
898 		if (IS_ERR(inode)) {
899 			err = PTR_ERR(inode);
900 			goto error;
901 		}
902 		v9fs_set_create_acl(inode, fid, dacl, pacl);
903 		d_instantiate(dentry, inode);
904 	}
905 error:
906 	if (fid)
907 		p9_client_clunk(fid);
908 	v9fs_put_acl(dacl, pacl);
909 	p9_client_clunk(dfid);
910 
911 	return err;
912 }
913 
914 /**
915  * v9fs_vfs_get_link_dotl - follow a symlink path
916  * @dentry: dentry for symlink
917  * @inode: inode for symlink
918  * @done: destructor for return value
919  */
920 
921 static const char *
922 v9fs_vfs_get_link_dotl(struct dentry *dentry,
923 		       struct inode *inode,
924 		       struct delayed_call *done)
925 {
926 	struct p9_fid *fid;
927 	char *target;
928 	int retval;
929 
930 	if (!dentry)
931 		return ERR_PTR(-ECHILD);
932 
933 	p9_debug(P9_DEBUG_VFS, "%pd\n", dentry);
934 
935 	fid = v9fs_fid_lookup(dentry);
936 	if (IS_ERR(fid))
937 		return ERR_CAST(fid);
938 	retval = p9_client_readlink(fid, &target);
939 	p9_client_clunk(fid);
940 	if (retval)
941 		return ERR_PTR(retval);
942 	set_delayed_call(done, kfree_link, target);
943 	return target;
944 }
945 
946 int v9fs_refresh_inode_dotl(struct p9_fid *fid, struct inode *inode)
947 {
948 	struct p9_stat_dotl *st;
949 	struct v9fs_session_info *v9ses;
950 	unsigned int flags;
951 
952 	v9ses = v9fs_inode2v9ses(inode);
953 	st = p9_client_getattr_dotl(fid, P9_STATS_ALL);
954 	if (IS_ERR(st))
955 		return PTR_ERR(st);
956 	/*
957 	 * Don't update inode if the file type is different
958 	 */
959 	if ((inode->i_mode & S_IFMT) != (st->st_mode & S_IFMT))
960 		goto out;
961 
962 	/*
963 	 * We don't want to refresh inode->i_size,
964 	 * because we may have cached data
965 	 */
966 	flags = (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) ?
967 		V9FS_STAT2INODE_KEEP_ISIZE : 0;
968 	v9fs_stat2inode_dotl(st, inode, flags);
969 out:
970 	kfree(st);
971 	return 0;
972 }
973 
974 const struct inode_operations v9fs_dir_inode_operations_dotl = {
975 	.create = v9fs_vfs_create_dotl,
976 	.atomic_open = v9fs_vfs_atomic_open_dotl,
977 	.lookup = v9fs_vfs_lookup,
978 	.link = v9fs_vfs_link_dotl,
979 	.symlink = v9fs_vfs_symlink_dotl,
980 	.unlink = v9fs_vfs_unlink,
981 	.mkdir = v9fs_vfs_mkdir_dotl,
982 	.rmdir = v9fs_vfs_rmdir,
983 	.mknod = v9fs_vfs_mknod_dotl,
984 	.rename = v9fs_vfs_rename,
985 	.getattr = v9fs_vfs_getattr_dotl,
986 	.setattr = v9fs_vfs_setattr_dotl,
987 	.listxattr = v9fs_listxattr,
988 	.get_acl = v9fs_iop_get_acl,
989 };
990 
991 const struct inode_operations v9fs_file_inode_operations_dotl = {
992 	.getattr = v9fs_vfs_getattr_dotl,
993 	.setattr = v9fs_vfs_setattr_dotl,
994 	.listxattr = v9fs_listxattr,
995 	.get_acl = v9fs_iop_get_acl,
996 };
997 
998 const struct inode_operations v9fs_symlink_inode_operations_dotl = {
999 	.get_link = v9fs_vfs_get_link_dotl,
1000 	.getattr = v9fs_vfs_getattr_dotl,
1001 	.setattr = v9fs_vfs_setattr_dotl,
1002 	.listxattr = v9fs_listxattr,
1003 };
1004