xref: /linux/fs/9p/vfs_inode_dotl.c (revision 791d3ef2e11100449837dc0b6fe884e60ca3a484)
1 /*
2  *  linux/fs/9p/vfs_inode_dotl.c
3  *
4  * This file contains vfs inode ops for the 9P2000.L protocol.
5  *
6  *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
7  *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
8  *
9  *  This program is free software; you can redistribute it and/or modify
10  *  it under the terms of the GNU General Public License version 2
11  *  as published by the Free Software Foundation.
12  *
13  *  This program is distributed in the hope that it will be useful,
14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  *  GNU General Public License for more details.
17  *
18  *  You should have received a copy of the GNU General Public License
19  *  along with this program; if not, write to:
20  *  Free Software Foundation
21  *  51 Franklin Street, Fifth Floor
22  *  Boston, MA  02111-1301  USA
23  *
24  */
25 
26 #include <linux/module.h>
27 #include <linux/errno.h>
28 #include <linux/fs.h>
29 #include <linux/file.h>
30 #include <linux/pagemap.h>
31 #include <linux/stat.h>
32 #include <linux/string.h>
33 #include <linux/inet.h>
34 #include <linux/namei.h>
35 #include <linux/idr.h>
36 #include <linux/sched.h>
37 #include <linux/slab.h>
38 #include <linux/xattr.h>
39 #include <linux/posix_acl.h>
40 #include <net/9p/9p.h>
41 #include <net/9p/client.h>
42 
43 #include "v9fs.h"
44 #include "v9fs_vfs.h"
45 #include "fid.h"
46 #include "cache.h"
47 #include "xattr.h"
48 #include "acl.h"
49 
50 static int
51 v9fs_vfs_mknod_dotl(struct inode *dir, struct dentry *dentry, umode_t omode,
52 		    dev_t rdev);
53 
54 /**
55  * v9fs_get_fsgid_for_create - Helper function to get the gid for creating a
56  * new file system object. This checks the S_ISGID to determine the owning
57  * group of the new file system object.
58  */
59 
60 static kgid_t v9fs_get_fsgid_for_create(struct inode *dir_inode)
61 {
62 	BUG_ON(dir_inode == NULL);
63 
64 	if (dir_inode->i_mode & S_ISGID) {
65 		/* set_gid bit is set.*/
66 		return dir_inode->i_gid;
67 	}
68 	return current_fsgid();
69 }
70 
71 static int v9fs_test_inode_dotl(struct inode *inode, void *data)
72 {
73 	struct v9fs_inode *v9inode = V9FS_I(inode);
74 	struct p9_stat_dotl *st = (struct p9_stat_dotl *)data;
75 
76 	/* don't match inode of different type */
77 	if ((inode->i_mode & S_IFMT) != (st->st_mode & S_IFMT))
78 		return 0;
79 
80 	if (inode->i_generation != st->st_gen)
81 		return 0;
82 
83 	/* compare qid details */
84 	if (memcmp(&v9inode->qid.version,
85 		   &st->qid.version, sizeof(v9inode->qid.version)))
86 		return 0;
87 
88 	if (v9inode->qid.type != st->qid.type)
89 		return 0;
90 
91 	if (v9inode->qid.path != st->qid.path)
92 		return 0;
93 	return 1;
94 }
95 
96 /* Always get a new inode */
97 static int v9fs_test_new_inode_dotl(struct inode *inode, void *data)
98 {
99 	return 0;
100 }
101 
102 static int v9fs_set_inode_dotl(struct inode *inode,  void *data)
103 {
104 	struct v9fs_inode *v9inode = V9FS_I(inode);
105 	struct p9_stat_dotl *st = (struct p9_stat_dotl *)data;
106 
107 	memcpy(&v9inode->qid, &st->qid, sizeof(st->qid));
108 	inode->i_generation = st->st_gen;
109 	return 0;
110 }
111 
112 static struct inode *v9fs_qid_iget_dotl(struct super_block *sb,
113 					struct p9_qid *qid,
114 					struct p9_fid *fid,
115 					struct p9_stat_dotl *st,
116 					int new)
117 {
118 	int retval;
119 	unsigned long i_ino;
120 	struct inode *inode;
121 	struct v9fs_session_info *v9ses = sb->s_fs_info;
122 	int (*test)(struct inode *, void *);
123 
124 	if (new)
125 		test = v9fs_test_new_inode_dotl;
126 	else
127 		test = v9fs_test_inode_dotl;
128 
129 	i_ino = v9fs_qid2ino(qid);
130 	inode = iget5_locked(sb, i_ino, test, v9fs_set_inode_dotl, st);
131 	if (!inode)
132 		return ERR_PTR(-ENOMEM);
133 	if (!(inode->i_state & I_NEW))
134 		return inode;
135 	/*
136 	 * initialize the inode with the stat info
137 	 * FIXME!! we may need support for stale inodes
138 	 * later.
139 	 */
140 	inode->i_ino = i_ino;
141 	retval = v9fs_init_inode(v9ses, inode,
142 				 st->st_mode, new_decode_dev(st->st_rdev));
143 	if (retval)
144 		goto error;
145 
146 	v9fs_stat2inode_dotl(st, inode);
147 	v9fs_cache_inode_get_cookie(inode);
148 	retval = v9fs_get_acl(inode, fid);
149 	if (retval)
150 		goto error;
151 
152 	unlock_new_inode(inode);
153 	return inode;
154 error:
155 	iget_failed(inode);
156 	return ERR_PTR(retval);
157 
158 }
159 
160 struct inode *
161 v9fs_inode_from_fid_dotl(struct v9fs_session_info *v9ses, struct p9_fid *fid,
162 			 struct super_block *sb, int new)
163 {
164 	struct p9_stat_dotl *st;
165 	struct inode *inode = NULL;
166 
167 	st = p9_client_getattr_dotl(fid, P9_STATS_BASIC | P9_STATS_GEN);
168 	if (IS_ERR(st))
169 		return ERR_CAST(st);
170 
171 	inode = v9fs_qid_iget_dotl(sb, &st->qid, fid, st, new);
172 	kfree(st);
173 	return inode;
174 }
175 
176 struct dotl_openflag_map {
177 	int open_flag;
178 	int dotl_flag;
179 };
180 
181 static int v9fs_mapped_dotl_flags(int flags)
182 {
183 	int i;
184 	int rflags = 0;
185 	struct dotl_openflag_map dotl_oflag_map[] = {
186 		{ O_CREAT,	P9_DOTL_CREATE },
187 		{ O_EXCL,	P9_DOTL_EXCL },
188 		{ O_NOCTTY,	P9_DOTL_NOCTTY },
189 		{ O_APPEND,	P9_DOTL_APPEND },
190 		{ O_NONBLOCK,	P9_DOTL_NONBLOCK },
191 		{ O_DSYNC,	P9_DOTL_DSYNC },
192 		{ FASYNC,	P9_DOTL_FASYNC },
193 		{ O_DIRECT,	P9_DOTL_DIRECT },
194 		{ O_LARGEFILE,	P9_DOTL_LARGEFILE },
195 		{ O_DIRECTORY,	P9_DOTL_DIRECTORY },
196 		{ O_NOFOLLOW,	P9_DOTL_NOFOLLOW },
197 		{ O_NOATIME,	P9_DOTL_NOATIME },
198 		{ O_CLOEXEC,	P9_DOTL_CLOEXEC },
199 		{ O_SYNC,	P9_DOTL_SYNC},
200 	};
201 	for (i = 0; i < ARRAY_SIZE(dotl_oflag_map); i++) {
202 		if (flags & dotl_oflag_map[i].open_flag)
203 			rflags |= dotl_oflag_map[i].dotl_flag;
204 	}
205 	return rflags;
206 }
207 
208 /**
209  * v9fs_open_to_dotl_flags- convert Linux specific open flags to
210  * plan 9 open flag.
211  * @flags: flags to convert
212  */
213 int v9fs_open_to_dotl_flags(int flags)
214 {
215 	int rflags = 0;
216 
217 	/*
218 	 * We have same bits for P9_DOTL_READONLY, P9_DOTL_WRONLY
219 	 * and P9_DOTL_NOACCESS
220 	 */
221 	rflags |= flags & O_ACCMODE;
222 	rflags |= v9fs_mapped_dotl_flags(flags);
223 
224 	return rflags;
225 }
226 
227 /**
228  * v9fs_vfs_create_dotl - VFS hook to create files for 9P2000.L protocol.
229  * @dir: directory inode that is being created
230  * @dentry:  dentry that is being deleted
231  * @omode: create permissions
232  *
233  */
234 
235 static int
236 v9fs_vfs_create_dotl(struct inode *dir, struct dentry *dentry, umode_t omode,
237 		bool excl)
238 {
239 	return v9fs_vfs_mknod_dotl(dir, dentry, omode, 0);
240 }
241 
242 static int
243 v9fs_vfs_atomic_open_dotl(struct inode *dir, struct dentry *dentry,
244 			  struct file *file, unsigned flags, umode_t omode,
245 			  int *opened)
246 {
247 	int err = 0;
248 	kgid_t gid;
249 	umode_t mode;
250 	const unsigned char *name = NULL;
251 	struct p9_qid qid;
252 	struct inode *inode;
253 	struct p9_fid *fid = NULL;
254 	struct v9fs_inode *v9inode;
255 	struct p9_fid *dfid, *ofid, *inode_fid;
256 	struct v9fs_session_info *v9ses;
257 	struct posix_acl *pacl = NULL, *dacl = NULL;
258 	struct dentry *res = NULL;
259 
260 	if (d_in_lookup(dentry)) {
261 		res = v9fs_vfs_lookup(dir, dentry, 0);
262 		if (IS_ERR(res))
263 			return PTR_ERR(res);
264 
265 		if (res)
266 			dentry = res;
267 	}
268 
269 	/* Only creates */
270 	if (!(flags & O_CREAT) || d_really_is_positive(dentry))
271 		return	finish_no_open(file, res);
272 
273 	v9ses = v9fs_inode2v9ses(dir);
274 
275 	name = dentry->d_name.name;
276 	p9_debug(P9_DEBUG_VFS, "name:%s flags:0x%x mode:0x%hx\n",
277 		 name, flags, omode);
278 
279 	dfid = v9fs_parent_fid(dentry);
280 	if (IS_ERR(dfid)) {
281 		err = PTR_ERR(dfid);
282 		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
283 		goto out;
284 	}
285 
286 	/* clone a fid to use for creation */
287 	ofid = clone_fid(dfid);
288 	if (IS_ERR(ofid)) {
289 		err = PTR_ERR(ofid);
290 		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
291 		goto out;
292 	}
293 
294 	gid = v9fs_get_fsgid_for_create(dir);
295 
296 	mode = omode;
297 	/* Update mode based on ACL value */
298 	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
299 	if (err) {
300 		p9_debug(P9_DEBUG_VFS, "Failed to get acl values in creat %d\n",
301 			 err);
302 		goto error;
303 	}
304 	err = p9_client_create_dotl(ofid, name, v9fs_open_to_dotl_flags(flags),
305 				    mode, gid, &qid);
306 	if (err < 0) {
307 		p9_debug(P9_DEBUG_VFS, "p9_client_open_dotl failed in creat %d\n",
308 			 err);
309 		goto error;
310 	}
311 	v9fs_invalidate_inode_attr(dir);
312 
313 	/* instantiate inode and assign the unopened fid to the dentry */
314 	fid = p9_client_walk(dfid, 1, &name, 1);
315 	if (IS_ERR(fid)) {
316 		err = PTR_ERR(fid);
317 		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
318 		fid = NULL;
319 		goto error;
320 	}
321 	inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
322 	if (IS_ERR(inode)) {
323 		err = PTR_ERR(inode);
324 		p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n", err);
325 		goto error;
326 	}
327 	/* Now set the ACL based on the default value */
328 	v9fs_set_create_acl(inode, fid, dacl, pacl);
329 
330 	v9fs_fid_add(dentry, fid);
331 	d_instantiate(dentry, inode);
332 
333 	v9inode = V9FS_I(inode);
334 	mutex_lock(&v9inode->v_mutex);
335 	if ((v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) &&
336 	    !v9inode->writeback_fid &&
337 	    ((flags & O_ACCMODE) != O_RDONLY)) {
338 		/*
339 		 * clone a fid and add it to writeback_fid
340 		 * we do it during open time instead of
341 		 * page dirty time via write_begin/page_mkwrite
342 		 * because we want write after unlink usecase
343 		 * to work.
344 		 */
345 		inode_fid = v9fs_writeback_fid(dentry);
346 		if (IS_ERR(inode_fid)) {
347 			err = PTR_ERR(inode_fid);
348 			mutex_unlock(&v9inode->v_mutex);
349 			goto err_clunk_old_fid;
350 		}
351 		v9inode->writeback_fid = (void *) inode_fid;
352 	}
353 	mutex_unlock(&v9inode->v_mutex);
354 	/* Since we are opening a file, assign the open fid to the file */
355 	err = finish_open(file, dentry, generic_file_open, opened);
356 	if (err)
357 		goto err_clunk_old_fid;
358 	file->private_data = ofid;
359 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
360 		v9fs_cache_inode_set_cookie(inode, file);
361 	*opened |= FILE_CREATED;
362 out:
363 	v9fs_put_acl(dacl, pacl);
364 	dput(res);
365 	return err;
366 
367 error:
368 	if (fid)
369 		p9_client_clunk(fid);
370 err_clunk_old_fid:
371 	if (ofid)
372 		p9_client_clunk(ofid);
373 	goto out;
374 }
375 
376 /**
377  * v9fs_vfs_mkdir_dotl - VFS mkdir hook to create a directory
378  * @dir:  inode that is being unlinked
379  * @dentry: dentry that is being unlinked
380  * @omode: mode for new directory
381  *
382  */
383 
384 static int v9fs_vfs_mkdir_dotl(struct inode *dir,
385 			       struct dentry *dentry, umode_t omode)
386 {
387 	int err;
388 	struct v9fs_session_info *v9ses;
389 	struct p9_fid *fid = NULL, *dfid = NULL;
390 	kgid_t gid;
391 	const unsigned char *name;
392 	umode_t mode;
393 	struct inode *inode;
394 	struct p9_qid qid;
395 	struct posix_acl *dacl = NULL, *pacl = NULL;
396 
397 	p9_debug(P9_DEBUG_VFS, "name %pd\n", dentry);
398 	err = 0;
399 	v9ses = v9fs_inode2v9ses(dir);
400 
401 	omode |= S_IFDIR;
402 	if (dir->i_mode & S_ISGID)
403 		omode |= S_ISGID;
404 
405 	dfid = v9fs_parent_fid(dentry);
406 	if (IS_ERR(dfid)) {
407 		err = PTR_ERR(dfid);
408 		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
409 		dfid = NULL;
410 		goto error;
411 	}
412 
413 	gid = v9fs_get_fsgid_for_create(dir);
414 	mode = omode;
415 	/* Update mode based on ACL value */
416 	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
417 	if (err) {
418 		p9_debug(P9_DEBUG_VFS, "Failed to get acl values in mkdir %d\n",
419 			 err);
420 		goto error;
421 	}
422 	name = dentry->d_name.name;
423 	err = p9_client_mkdir_dotl(dfid, name, mode, gid, &qid);
424 	if (err < 0)
425 		goto error;
426 
427 	fid = p9_client_walk(dfid, 1, &name, 1);
428 	if (IS_ERR(fid)) {
429 		err = PTR_ERR(fid);
430 		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
431 			 err);
432 		fid = NULL;
433 		goto error;
434 	}
435 
436 	/* instantiate inode and assign the unopened fid to the dentry */
437 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
438 		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
439 		if (IS_ERR(inode)) {
440 			err = PTR_ERR(inode);
441 			p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n",
442 				 err);
443 			goto error;
444 		}
445 		v9fs_fid_add(dentry, fid);
446 		v9fs_set_create_acl(inode, fid, dacl, pacl);
447 		d_instantiate(dentry, inode);
448 		fid = NULL;
449 		err = 0;
450 	} else {
451 		/*
452 		 * Not in cached mode. No need to populate
453 		 * inode with stat. We need to get an inode
454 		 * so that we can set the acl with dentry
455 		 */
456 		inode = v9fs_get_inode(dir->i_sb, mode, 0);
457 		if (IS_ERR(inode)) {
458 			err = PTR_ERR(inode);
459 			goto error;
460 		}
461 		v9fs_set_create_acl(inode, fid, dacl, pacl);
462 		d_instantiate(dentry, inode);
463 	}
464 	inc_nlink(dir);
465 	v9fs_invalidate_inode_attr(dir);
466 error:
467 	if (fid)
468 		p9_client_clunk(fid);
469 	v9fs_put_acl(dacl, pacl);
470 	return err;
471 }
472 
473 static int
474 v9fs_vfs_getattr_dotl(const struct path *path, struct kstat *stat,
475 		 u32 request_mask, unsigned int flags)
476 {
477 	struct dentry *dentry = path->dentry;
478 	struct v9fs_session_info *v9ses;
479 	struct p9_fid *fid;
480 	struct p9_stat_dotl *st;
481 
482 	p9_debug(P9_DEBUG_VFS, "dentry: %p\n", dentry);
483 	v9ses = v9fs_dentry2v9ses(dentry);
484 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
485 		generic_fillattr(d_inode(dentry), stat);
486 		return 0;
487 	}
488 	fid = v9fs_fid_lookup(dentry);
489 	if (IS_ERR(fid))
490 		return PTR_ERR(fid);
491 
492 	/* Ask for all the fields in stat structure. Server will return
493 	 * whatever it supports
494 	 */
495 
496 	st = p9_client_getattr_dotl(fid, P9_STATS_ALL);
497 	if (IS_ERR(st))
498 		return PTR_ERR(st);
499 
500 	v9fs_stat2inode_dotl(st, d_inode(dentry));
501 	generic_fillattr(d_inode(dentry), stat);
502 	/* Change block size to what the server returned */
503 	stat->blksize = st->st_blksize;
504 
505 	kfree(st);
506 	return 0;
507 }
508 
509 /*
510  * Attribute flags.
511  */
512 #define P9_ATTR_MODE		(1 << 0)
513 #define P9_ATTR_UID		(1 << 1)
514 #define P9_ATTR_GID		(1 << 2)
515 #define P9_ATTR_SIZE		(1 << 3)
516 #define P9_ATTR_ATIME		(1 << 4)
517 #define P9_ATTR_MTIME		(1 << 5)
518 #define P9_ATTR_CTIME		(1 << 6)
519 #define P9_ATTR_ATIME_SET	(1 << 7)
520 #define P9_ATTR_MTIME_SET	(1 << 8)
521 
522 struct dotl_iattr_map {
523 	int iattr_valid;
524 	int p9_iattr_valid;
525 };
526 
527 static int v9fs_mapped_iattr_valid(int iattr_valid)
528 {
529 	int i;
530 	int p9_iattr_valid = 0;
531 	struct dotl_iattr_map dotl_iattr_map[] = {
532 		{ ATTR_MODE,		P9_ATTR_MODE },
533 		{ ATTR_UID,		P9_ATTR_UID },
534 		{ ATTR_GID,		P9_ATTR_GID },
535 		{ ATTR_SIZE,		P9_ATTR_SIZE },
536 		{ ATTR_ATIME,		P9_ATTR_ATIME },
537 		{ ATTR_MTIME,		P9_ATTR_MTIME },
538 		{ ATTR_CTIME,		P9_ATTR_CTIME },
539 		{ ATTR_ATIME_SET,	P9_ATTR_ATIME_SET },
540 		{ ATTR_MTIME_SET,	P9_ATTR_MTIME_SET },
541 	};
542 	for (i = 0; i < ARRAY_SIZE(dotl_iattr_map); i++) {
543 		if (iattr_valid & dotl_iattr_map[i].iattr_valid)
544 			p9_iattr_valid |= dotl_iattr_map[i].p9_iattr_valid;
545 	}
546 	return p9_iattr_valid;
547 }
548 
549 /**
550  * v9fs_vfs_setattr_dotl - set file metadata
551  * @dentry: file whose metadata to set
552  * @iattr: metadata assignment structure
553  *
554  */
555 
556 int v9fs_vfs_setattr_dotl(struct dentry *dentry, struct iattr *iattr)
557 {
558 	int retval;
559 	struct p9_fid *fid;
560 	struct p9_iattr_dotl p9attr;
561 	struct inode *inode = d_inode(dentry);
562 
563 	p9_debug(P9_DEBUG_VFS, "\n");
564 
565 	retval = setattr_prepare(dentry, iattr);
566 	if (retval)
567 		return retval;
568 
569 	p9attr.valid = v9fs_mapped_iattr_valid(iattr->ia_valid);
570 	p9attr.mode = iattr->ia_mode;
571 	p9attr.uid = iattr->ia_uid;
572 	p9attr.gid = iattr->ia_gid;
573 	p9attr.size = iattr->ia_size;
574 	p9attr.atime_sec = iattr->ia_atime.tv_sec;
575 	p9attr.atime_nsec = iattr->ia_atime.tv_nsec;
576 	p9attr.mtime_sec = iattr->ia_mtime.tv_sec;
577 	p9attr.mtime_nsec = iattr->ia_mtime.tv_nsec;
578 
579 	fid = v9fs_fid_lookup(dentry);
580 	if (IS_ERR(fid))
581 		return PTR_ERR(fid);
582 
583 	/* Write all dirty data */
584 	if (S_ISREG(inode->i_mode))
585 		filemap_write_and_wait(inode->i_mapping);
586 
587 	retval = p9_client_setattr(fid, &p9attr);
588 	if (retval < 0)
589 		return retval;
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(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 			return retval;
603 	}
604 	return 0;
605 }
606 
607 /**
608  * v9fs_stat2inode_dotl - populate an inode structure with stat info
609  * @stat: stat structure
610  * @inode: inode to populate
611  *
612  */
613 
614 void
615 v9fs_stat2inode_dotl(struct p9_stat_dotl *stat, struct inode *inode)
616 {
617 	umode_t mode;
618 	struct v9fs_inode *v9inode = V9FS_I(inode);
619 
620 	if ((stat->st_result_mask & P9_STATS_BASIC) == P9_STATS_BASIC) {
621 		inode->i_atime.tv_sec = stat->st_atime_sec;
622 		inode->i_atime.tv_nsec = stat->st_atime_nsec;
623 		inode->i_mtime.tv_sec = stat->st_mtime_sec;
624 		inode->i_mtime.tv_nsec = stat->st_mtime_nsec;
625 		inode->i_ctime.tv_sec = stat->st_ctime_sec;
626 		inode->i_ctime.tv_nsec = stat->st_ctime_nsec;
627 		inode->i_uid = stat->st_uid;
628 		inode->i_gid = stat->st_gid;
629 		set_nlink(inode, stat->st_nlink);
630 
631 		mode = stat->st_mode & S_IALLUGO;
632 		mode |= inode->i_mode & ~S_IALLUGO;
633 		inode->i_mode = mode;
634 
635 		i_size_write(inode, stat->st_size);
636 		inode->i_blocks = stat->st_blocks;
637 	} else {
638 		if (stat->st_result_mask & P9_STATS_ATIME) {
639 			inode->i_atime.tv_sec = stat->st_atime_sec;
640 			inode->i_atime.tv_nsec = stat->st_atime_nsec;
641 		}
642 		if (stat->st_result_mask & P9_STATS_MTIME) {
643 			inode->i_mtime.tv_sec = stat->st_mtime_sec;
644 			inode->i_mtime.tv_nsec = stat->st_mtime_nsec;
645 		}
646 		if (stat->st_result_mask & P9_STATS_CTIME) {
647 			inode->i_ctime.tv_sec = stat->st_ctime_sec;
648 			inode->i_ctime.tv_nsec = stat->st_ctime_nsec;
649 		}
650 		if (stat->st_result_mask & P9_STATS_UID)
651 			inode->i_uid = stat->st_uid;
652 		if (stat->st_result_mask & P9_STATS_GID)
653 			inode->i_gid = stat->st_gid;
654 		if (stat->st_result_mask & P9_STATS_NLINK)
655 			set_nlink(inode, stat->st_nlink);
656 		if (stat->st_result_mask & P9_STATS_MODE) {
657 			inode->i_mode = stat->st_mode;
658 			if ((S_ISBLK(inode->i_mode)) ||
659 						(S_ISCHR(inode->i_mode)))
660 				init_special_inode(inode, inode->i_mode,
661 								inode->i_rdev);
662 		}
663 		if (stat->st_result_mask & P9_STATS_RDEV)
664 			inode->i_rdev = new_decode_dev(stat->st_rdev);
665 		if (stat->st_result_mask & P9_STATS_SIZE)
666 			i_size_write(inode, stat->st_size);
667 		if (stat->st_result_mask & P9_STATS_BLOCKS)
668 			inode->i_blocks = stat->st_blocks;
669 	}
670 	if (stat->st_result_mask & P9_STATS_GEN)
671 		inode->i_generation = stat->st_gen;
672 
673 	/* Currently we don't support P9_STATS_BTIME and P9_STATS_DATA_VERSION
674 	 * because the inode structure does not have fields for them.
675 	 */
676 	v9inode->cache_validity &= ~V9FS_INO_INVALID_ATTR;
677 }
678 
679 static int
680 v9fs_vfs_symlink_dotl(struct inode *dir, struct dentry *dentry,
681 		const char *symname)
682 {
683 	int err;
684 	kgid_t gid;
685 	const unsigned char *name;
686 	struct p9_qid qid;
687 	struct inode *inode;
688 	struct p9_fid *dfid;
689 	struct p9_fid *fid = NULL;
690 	struct v9fs_session_info *v9ses;
691 
692 	name = dentry->d_name.name;
693 	p9_debug(P9_DEBUG_VFS, "%lu,%s,%s\n", dir->i_ino, name, symname);
694 	v9ses = v9fs_inode2v9ses(dir);
695 
696 	dfid = v9fs_parent_fid(dentry);
697 	if (IS_ERR(dfid)) {
698 		err = PTR_ERR(dfid);
699 		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
700 		return err;
701 	}
702 
703 	gid = v9fs_get_fsgid_for_create(dir);
704 
705 	/* Server doesn't alter fid on TSYMLINK. Hence no need to clone it. */
706 	err = p9_client_symlink(dfid, name, symname, gid, &qid);
707 
708 	if (err < 0) {
709 		p9_debug(P9_DEBUG_VFS, "p9_client_symlink failed %d\n", err);
710 		goto error;
711 	}
712 
713 	v9fs_invalidate_inode_attr(dir);
714 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
715 		/* Now walk from the parent so we can get an unopened fid. */
716 		fid = p9_client_walk(dfid, 1, &name, 1);
717 		if (IS_ERR(fid)) {
718 			err = PTR_ERR(fid);
719 			p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
720 				 err);
721 			fid = NULL;
722 			goto error;
723 		}
724 
725 		/* instantiate inode and assign the unopened fid to dentry */
726 		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
727 		if (IS_ERR(inode)) {
728 			err = PTR_ERR(inode);
729 			p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n",
730 				 err);
731 			goto error;
732 		}
733 		v9fs_fid_add(dentry, fid);
734 		d_instantiate(dentry, inode);
735 		fid = NULL;
736 		err = 0;
737 	} else {
738 		/* Not in cached mode. No need to populate inode with stat */
739 		inode = v9fs_get_inode(dir->i_sb, S_IFLNK, 0);
740 		if (IS_ERR(inode)) {
741 			err = PTR_ERR(inode);
742 			goto error;
743 		}
744 		d_instantiate(dentry, inode);
745 	}
746 
747 error:
748 	if (fid)
749 		p9_client_clunk(fid);
750 
751 	return err;
752 }
753 
754 /**
755  * v9fs_vfs_link_dotl - create a hardlink for dotl
756  * @old_dentry: dentry for file to link to
757  * @dir: inode destination for new link
758  * @dentry: dentry for link
759  *
760  */
761 
762 static int
763 v9fs_vfs_link_dotl(struct dentry *old_dentry, struct inode *dir,
764 		struct dentry *dentry)
765 {
766 	int err;
767 	struct p9_fid *dfid, *oldfid;
768 	struct v9fs_session_info *v9ses;
769 
770 	p9_debug(P9_DEBUG_VFS, "dir ino: %lu, old_name: %pd, new_name: %pd\n",
771 		 dir->i_ino, old_dentry, dentry);
772 
773 	v9ses = v9fs_inode2v9ses(dir);
774 	dfid = v9fs_parent_fid(dentry);
775 	if (IS_ERR(dfid))
776 		return PTR_ERR(dfid);
777 
778 	oldfid = v9fs_fid_lookup(old_dentry);
779 	if (IS_ERR(oldfid))
780 		return PTR_ERR(oldfid);
781 
782 	err = p9_client_link(dfid, oldfid, dentry->d_name.name);
783 
784 	if (err < 0) {
785 		p9_debug(P9_DEBUG_VFS, "p9_client_link failed %d\n", err);
786 		return err;
787 	}
788 
789 	v9fs_invalidate_inode_attr(dir);
790 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
791 		/* Get the latest stat info from server. */
792 		struct p9_fid *fid;
793 		fid = v9fs_fid_lookup(old_dentry);
794 		if (IS_ERR(fid))
795 			return PTR_ERR(fid);
796 
797 		v9fs_refresh_inode_dotl(fid, d_inode(old_dentry));
798 	}
799 	ihold(d_inode(old_dentry));
800 	d_instantiate(dentry, d_inode(old_dentry));
801 
802 	return err;
803 }
804 
805 /**
806  * v9fs_vfs_mknod_dotl - create a special file
807  * @dir: inode destination for new link
808  * @dentry: dentry for file
809  * @omode: mode for creation
810  * @rdev: device associated with special file
811  *
812  */
813 static int
814 v9fs_vfs_mknod_dotl(struct inode *dir, struct dentry *dentry, umode_t omode,
815 		dev_t rdev)
816 {
817 	int err;
818 	kgid_t gid;
819 	const unsigned char *name;
820 	umode_t mode;
821 	struct v9fs_session_info *v9ses;
822 	struct p9_fid *fid = NULL, *dfid = NULL;
823 	struct inode *inode;
824 	struct p9_qid qid;
825 	struct posix_acl *dacl = NULL, *pacl = NULL;
826 
827 	p9_debug(P9_DEBUG_VFS, " %lu,%pd mode: %hx MAJOR: %u MINOR: %u\n",
828 		 dir->i_ino, dentry, omode,
829 		 MAJOR(rdev), MINOR(rdev));
830 
831 	v9ses = v9fs_inode2v9ses(dir);
832 	dfid = v9fs_parent_fid(dentry);
833 	if (IS_ERR(dfid)) {
834 		err = PTR_ERR(dfid);
835 		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
836 		dfid = NULL;
837 		goto error;
838 	}
839 
840 	gid = v9fs_get_fsgid_for_create(dir);
841 	mode = omode;
842 	/* Update mode based on ACL value */
843 	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
844 	if (err) {
845 		p9_debug(P9_DEBUG_VFS, "Failed to get acl values in mknod %d\n",
846 			 err);
847 		goto error;
848 	}
849 	name = dentry->d_name.name;
850 
851 	err = p9_client_mknod_dotl(dfid, name, mode, rdev, gid, &qid);
852 	if (err < 0)
853 		goto error;
854 
855 	v9fs_invalidate_inode_attr(dir);
856 	fid = p9_client_walk(dfid, 1, &name, 1);
857 	if (IS_ERR(fid)) {
858 		err = PTR_ERR(fid);
859 		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
860 			 err);
861 		fid = NULL;
862 		goto error;
863 	}
864 
865 	/* instantiate inode and assign the unopened fid to the dentry */
866 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
867 		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
868 		if (IS_ERR(inode)) {
869 			err = PTR_ERR(inode);
870 			p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n",
871 				 err);
872 			goto error;
873 		}
874 		v9fs_set_create_acl(inode, fid, dacl, pacl);
875 		v9fs_fid_add(dentry, fid);
876 		d_instantiate(dentry, inode);
877 		fid = NULL;
878 		err = 0;
879 	} else {
880 		/*
881 		 * Not in cached mode. No need to populate inode with stat.
882 		 * socket syscall returns a fd, so we need instantiate
883 		 */
884 		inode = v9fs_get_inode(dir->i_sb, mode, rdev);
885 		if (IS_ERR(inode)) {
886 			err = PTR_ERR(inode);
887 			goto error;
888 		}
889 		v9fs_set_create_acl(inode, fid, dacl, pacl);
890 		d_instantiate(dentry, inode);
891 	}
892 error:
893 	if (fid)
894 		p9_client_clunk(fid);
895 	v9fs_put_acl(dacl, pacl);
896 	return err;
897 }
898 
899 /**
900  * v9fs_vfs_get_link_dotl - follow a symlink path
901  * @dentry: dentry for symlink
902  * @inode: inode for symlink
903  * @done: destructor for return value
904  */
905 
906 static const char *
907 v9fs_vfs_get_link_dotl(struct dentry *dentry,
908 		       struct inode *inode,
909 		       struct delayed_call *done)
910 {
911 	struct p9_fid *fid;
912 	char *target;
913 	int retval;
914 
915 	if (!dentry)
916 		return ERR_PTR(-ECHILD);
917 
918 	p9_debug(P9_DEBUG_VFS, "%pd\n", dentry);
919 
920 	fid = v9fs_fid_lookup(dentry);
921 	if (IS_ERR(fid))
922 		return ERR_CAST(fid);
923 	retval = p9_client_readlink(fid, &target);
924 	if (retval)
925 		return ERR_PTR(retval);
926 	set_delayed_call(done, kfree_link, target);
927 	return target;
928 }
929 
930 int v9fs_refresh_inode_dotl(struct p9_fid *fid, struct inode *inode)
931 {
932 	loff_t i_size;
933 	struct p9_stat_dotl *st;
934 	struct v9fs_session_info *v9ses;
935 
936 	v9ses = v9fs_inode2v9ses(inode);
937 	st = p9_client_getattr_dotl(fid, P9_STATS_ALL);
938 	if (IS_ERR(st))
939 		return PTR_ERR(st);
940 	/*
941 	 * Don't update inode if the file type is different
942 	 */
943 	if ((inode->i_mode & S_IFMT) != (st->st_mode & S_IFMT))
944 		goto out;
945 
946 	spin_lock(&inode->i_lock);
947 	/*
948 	 * We don't want to refresh inode->i_size,
949 	 * because we may have cached data
950 	 */
951 	i_size = inode->i_size;
952 	v9fs_stat2inode_dotl(st, inode);
953 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
954 		inode->i_size = i_size;
955 	spin_unlock(&inode->i_lock);
956 out:
957 	kfree(st);
958 	return 0;
959 }
960 
961 const struct inode_operations v9fs_dir_inode_operations_dotl = {
962 	.create = v9fs_vfs_create_dotl,
963 	.atomic_open = v9fs_vfs_atomic_open_dotl,
964 	.lookup = v9fs_vfs_lookup,
965 	.link = v9fs_vfs_link_dotl,
966 	.symlink = v9fs_vfs_symlink_dotl,
967 	.unlink = v9fs_vfs_unlink,
968 	.mkdir = v9fs_vfs_mkdir_dotl,
969 	.rmdir = v9fs_vfs_rmdir,
970 	.mknod = v9fs_vfs_mknod_dotl,
971 	.rename = v9fs_vfs_rename,
972 	.getattr = v9fs_vfs_getattr_dotl,
973 	.setattr = v9fs_vfs_setattr_dotl,
974 	.listxattr = v9fs_listxattr,
975 	.get_acl = v9fs_iop_get_acl,
976 };
977 
978 const struct inode_operations v9fs_file_inode_operations_dotl = {
979 	.getattr = v9fs_vfs_getattr_dotl,
980 	.setattr = v9fs_vfs_setattr_dotl,
981 	.listxattr = v9fs_listxattr,
982 	.get_acl = v9fs_iop_get_acl,
983 };
984 
985 const struct inode_operations v9fs_symlink_inode_operations_dotl = {
986 	.get_link = v9fs_vfs_get_link_dotl,
987 	.getattr = v9fs_vfs_getattr_dotl,
988 	.setattr = v9fs_vfs_setattr_dotl,
989 	.listxattr = v9fs_listxattr,
990 };
991