xref: /linux/fs/9p/vfs_inode_dotl.c (revision f2ee442115c9b6219083c019939a9cc0c9abb2f8)
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, int 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 gid_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 /**
72  * v9fs_dentry_from_dir_inode - helper function to get the dentry from
73  * dir inode.
74  *
75  */
76 
77 static struct dentry *v9fs_dentry_from_dir_inode(struct inode *inode)
78 {
79 	struct dentry *dentry;
80 
81 	spin_lock(&inode->i_lock);
82 	/* Directory should have only one entry. */
83 	BUG_ON(S_ISDIR(inode->i_mode) && !list_is_singular(&inode->i_dentry));
84 	dentry = list_entry(inode->i_dentry.next, struct dentry, d_alias);
85 	spin_unlock(&inode->i_lock);
86 	return dentry;
87 }
88 
89 static int v9fs_test_inode_dotl(struct inode *inode, void *data)
90 {
91 	struct v9fs_inode *v9inode = V9FS_I(inode);
92 	struct p9_stat_dotl *st = (struct p9_stat_dotl *)data;
93 
94 	/* don't match inode of different type */
95 	if ((inode->i_mode & S_IFMT) != (st->st_mode & S_IFMT))
96 		return 0;
97 
98 	if (inode->i_generation != st->st_gen)
99 		return 0;
100 
101 	/* compare qid details */
102 	if (memcmp(&v9inode->qid.version,
103 		   &st->qid.version, sizeof(v9inode->qid.version)))
104 		return 0;
105 
106 	if (v9inode->qid.type != st->qid.type)
107 		return 0;
108 	return 1;
109 }
110 
111 /* Always get a new inode */
112 static int v9fs_test_new_inode_dotl(struct inode *inode, void *data)
113 {
114 	return 0;
115 }
116 
117 static int v9fs_set_inode_dotl(struct inode *inode,  void *data)
118 {
119 	struct v9fs_inode *v9inode = V9FS_I(inode);
120 	struct p9_stat_dotl *st = (struct p9_stat_dotl *)data;
121 
122 	memcpy(&v9inode->qid, &st->qid, sizeof(st->qid));
123 	inode->i_generation = st->st_gen;
124 	return 0;
125 }
126 
127 static struct inode *v9fs_qid_iget_dotl(struct super_block *sb,
128 					struct p9_qid *qid,
129 					struct p9_fid *fid,
130 					struct p9_stat_dotl *st,
131 					int new)
132 {
133 	int retval;
134 	unsigned long i_ino;
135 	struct inode *inode;
136 	struct v9fs_session_info *v9ses = sb->s_fs_info;
137 	int (*test)(struct inode *, void *);
138 
139 	if (new)
140 		test = v9fs_test_new_inode_dotl;
141 	else
142 		test = v9fs_test_inode_dotl;
143 
144 	i_ino = v9fs_qid2ino(qid);
145 	inode = iget5_locked(sb, i_ino, test, v9fs_set_inode_dotl, st);
146 	if (!inode)
147 		return ERR_PTR(-ENOMEM);
148 	if (!(inode->i_state & I_NEW))
149 		return inode;
150 	/*
151 	 * initialize the inode with the stat info
152 	 * FIXME!! we may need support for stale inodes
153 	 * later.
154 	 */
155 	inode->i_ino = i_ino;
156 	retval = v9fs_init_inode(v9ses, inode,
157 				 st->st_mode, new_decode_dev(st->st_rdev));
158 	if (retval)
159 		goto error;
160 
161 	v9fs_stat2inode_dotl(st, inode);
162 #ifdef CONFIG_9P_FSCACHE
163 	v9fs_cache_inode_get_cookie(inode);
164 #endif
165 	retval = v9fs_get_acl(inode, fid);
166 	if (retval)
167 		goto error;
168 
169 	unlock_new_inode(inode);
170 	return inode;
171 error:
172 	unlock_new_inode(inode);
173 	iput(inode);
174 	return ERR_PTR(retval);
175 
176 }
177 
178 struct inode *
179 v9fs_inode_from_fid_dotl(struct v9fs_session_info *v9ses, struct p9_fid *fid,
180 			 struct super_block *sb, int new)
181 {
182 	struct p9_stat_dotl *st;
183 	struct inode *inode = NULL;
184 
185 	st = p9_client_getattr_dotl(fid, P9_STATS_BASIC | P9_STATS_GEN);
186 	if (IS_ERR(st))
187 		return ERR_CAST(st);
188 
189 	inode = v9fs_qid_iget_dotl(sb, &st->qid, fid, st, new);
190 	kfree(st);
191 	return inode;
192 }
193 
194 struct dotl_openflag_map {
195 	int open_flag;
196 	int dotl_flag;
197 };
198 
199 static int v9fs_mapped_dotl_flags(int flags)
200 {
201 	int i;
202 	int rflags = 0;
203 	struct dotl_openflag_map dotl_oflag_map[] = {
204 		{ O_CREAT,	P9_DOTL_CREATE },
205 		{ O_EXCL,	P9_DOTL_EXCL },
206 		{ O_NOCTTY,	P9_DOTL_NOCTTY },
207 		{ O_TRUNC,	P9_DOTL_TRUNC },
208 		{ O_APPEND,	P9_DOTL_APPEND },
209 		{ O_NONBLOCK,	P9_DOTL_NONBLOCK },
210 		{ O_DSYNC,	P9_DOTL_DSYNC },
211 		{ FASYNC,	P9_DOTL_FASYNC },
212 		{ O_DIRECT,	P9_DOTL_DIRECT },
213 		{ O_LARGEFILE,	P9_DOTL_LARGEFILE },
214 		{ O_DIRECTORY,	P9_DOTL_DIRECTORY },
215 		{ O_NOFOLLOW,	P9_DOTL_NOFOLLOW },
216 		{ O_NOATIME,	P9_DOTL_NOATIME },
217 		{ O_CLOEXEC,	P9_DOTL_CLOEXEC },
218 		{ O_SYNC,	P9_DOTL_SYNC},
219 	};
220 	for (i = 0; i < ARRAY_SIZE(dotl_oflag_map); i++) {
221 		if (flags & dotl_oflag_map[i].open_flag)
222 			rflags |= dotl_oflag_map[i].dotl_flag;
223 	}
224 	return rflags;
225 }
226 
227 /**
228  * v9fs_open_to_dotl_flags- convert Linux specific open flags to
229  * plan 9 open flag.
230  * @flags: flags to convert
231  */
232 int v9fs_open_to_dotl_flags(int flags)
233 {
234 	int rflags = 0;
235 
236 	/*
237 	 * We have same bits for P9_DOTL_READONLY, P9_DOTL_WRONLY
238 	 * and P9_DOTL_NOACCESS
239 	 */
240 	rflags |= flags & O_ACCMODE;
241 	rflags |= v9fs_mapped_dotl_flags(flags);
242 
243 	return rflags;
244 }
245 
246 /**
247  * v9fs_vfs_create_dotl - VFS hook to create files for 9P2000.L protocol.
248  * @dir: directory inode that is being created
249  * @dentry:  dentry that is being deleted
250  * @mode: create permissions
251  * @nd: path information
252  *
253  */
254 
255 static int
256 v9fs_vfs_create_dotl(struct inode *dir, struct dentry *dentry, int omode,
257 		struct nameidata *nd)
258 {
259 	int err = 0;
260 	gid_t gid;
261 	int flags;
262 	umode_t mode;
263 	char *name = NULL;
264 	struct file *filp;
265 	struct p9_qid qid;
266 	struct inode *inode;
267 	struct p9_fid *fid = NULL;
268 	struct v9fs_inode *v9inode;
269 	struct p9_fid *dfid, *ofid, *inode_fid;
270 	struct v9fs_session_info *v9ses;
271 	struct posix_acl *pacl = NULL, *dacl = NULL;
272 
273 	v9ses = v9fs_inode2v9ses(dir);
274 	if (nd)
275 		flags = nd->intent.open.flags;
276 	else {
277 		/*
278 		 * create call without LOOKUP_OPEN is due
279 		 * to mknod of regular files. So use mknod
280 		 * operation.
281 		 */
282 		return v9fs_vfs_mknod_dotl(dir, dentry, omode, 0);
283 	}
284 
285 	name = (char *) dentry->d_name.name;
286 	P9_DPRINTK(P9_DEBUG_VFS, "v9fs_vfs_create_dotl: name:%s flags:0x%x "
287 			"mode:0x%x\n", name, flags, omode);
288 
289 	dfid = v9fs_fid_lookup(dentry->d_parent);
290 	if (IS_ERR(dfid)) {
291 		err = PTR_ERR(dfid);
292 		P9_DPRINTK(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
293 		return err;
294 	}
295 
296 	/* clone a fid to use for creation */
297 	ofid = p9_client_walk(dfid, 0, NULL, 1);
298 	if (IS_ERR(ofid)) {
299 		err = PTR_ERR(ofid);
300 		P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
301 		return err;
302 	}
303 
304 	gid = v9fs_get_fsgid_for_create(dir);
305 
306 	mode = omode;
307 	/* Update mode based on ACL value */
308 	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
309 	if (err) {
310 		P9_DPRINTK(P9_DEBUG_VFS,
311 			   "Failed to get acl values in creat %d\n", err);
312 		goto error;
313 	}
314 	err = p9_client_create_dotl(ofid, name, v9fs_open_to_dotl_flags(flags),
315 				    mode, gid, &qid);
316 	if (err < 0) {
317 		P9_DPRINTK(P9_DEBUG_VFS,
318 				"p9_client_open_dotl failed in creat %d\n",
319 				err);
320 		goto error;
321 	}
322 	v9fs_invalidate_inode_attr(dir);
323 
324 	/* instantiate inode and assign the unopened fid to the dentry */
325 	fid = p9_client_walk(dfid, 1, &name, 1);
326 	if (IS_ERR(fid)) {
327 		err = PTR_ERR(fid);
328 		P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
329 		fid = NULL;
330 		goto error;
331 	}
332 	inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
333 	if (IS_ERR(inode)) {
334 		err = PTR_ERR(inode);
335 		P9_DPRINTK(P9_DEBUG_VFS, "inode creation failed %d\n", err);
336 		goto error;
337 	}
338 	err = v9fs_fid_add(dentry, fid);
339 	if (err < 0)
340 		goto error;
341 	d_instantiate(dentry, inode);
342 
343 	/* Now set the ACL based on the default value */
344 	v9fs_set_create_acl(dentry, &dacl, &pacl);
345 
346 	v9inode = V9FS_I(inode);
347 	mutex_lock(&v9inode->v_mutex);
348 	if (v9ses->cache && !v9inode->writeback_fid &&
349 	    ((flags & O_ACCMODE) != O_RDONLY)) {
350 		/*
351 		 * clone a fid and add it to writeback_fid
352 		 * we do it during open time instead of
353 		 * page dirty time via write_begin/page_mkwrite
354 		 * because we want write after unlink usecase
355 		 * to work.
356 		 */
357 		inode_fid = v9fs_writeback_fid(dentry);
358 		if (IS_ERR(inode_fid)) {
359 			err = PTR_ERR(inode_fid);
360 			mutex_unlock(&v9inode->v_mutex);
361 			goto err_clunk_old_fid;
362 		}
363 		v9inode->writeback_fid = (void *) inode_fid;
364 	}
365 	mutex_unlock(&v9inode->v_mutex);
366 	/* Since we are opening a file, assign the open fid to the file */
367 	filp = lookup_instantiate_filp(nd, dentry, generic_file_open);
368 	if (IS_ERR(filp)) {
369 		err = PTR_ERR(filp);
370 		goto err_clunk_old_fid;
371 	}
372 	filp->private_data = ofid;
373 #ifdef CONFIG_9P_FSCACHE
374 	if (v9ses->cache)
375 		v9fs_cache_inode_set_cookie(inode, filp);
376 #endif
377 	return 0;
378 
379 error:
380 	if (fid)
381 		p9_client_clunk(fid);
382 err_clunk_old_fid:
383 	if (ofid)
384 		p9_client_clunk(ofid);
385 	v9fs_set_create_acl(NULL, &dacl, &pacl);
386 	return err;
387 }
388 
389 /**
390  * v9fs_vfs_mkdir_dotl - VFS mkdir hook to create a directory
391  * @dir:  inode that is being unlinked
392  * @dentry: dentry that is being unlinked
393  * @mode: mode for new directory
394  *
395  */
396 
397 static int v9fs_vfs_mkdir_dotl(struct inode *dir,
398 			       struct dentry *dentry, int omode)
399 {
400 	int err;
401 	struct v9fs_session_info *v9ses;
402 	struct p9_fid *fid = NULL, *dfid = NULL;
403 	gid_t gid;
404 	char *name;
405 	umode_t mode;
406 	struct inode *inode;
407 	struct p9_qid qid;
408 	struct dentry *dir_dentry;
409 	struct posix_acl *dacl = NULL, *pacl = NULL;
410 
411 	P9_DPRINTK(P9_DEBUG_VFS, "name %s\n", dentry->d_name.name);
412 	err = 0;
413 	v9ses = v9fs_inode2v9ses(dir);
414 
415 	omode |= S_IFDIR;
416 	if (dir->i_mode & S_ISGID)
417 		omode |= S_ISGID;
418 
419 	dir_dentry = v9fs_dentry_from_dir_inode(dir);
420 	dfid = v9fs_fid_lookup(dir_dentry);
421 	if (IS_ERR(dfid)) {
422 		err = PTR_ERR(dfid);
423 		P9_DPRINTK(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
424 		dfid = NULL;
425 		goto error;
426 	}
427 
428 	gid = v9fs_get_fsgid_for_create(dir);
429 	mode = omode;
430 	/* Update mode based on ACL value */
431 	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
432 	if (err) {
433 		P9_DPRINTK(P9_DEBUG_VFS,
434 			   "Failed to get acl values in mkdir %d\n", err);
435 		goto error;
436 	}
437 	name = (char *) dentry->d_name.name;
438 	err = p9_client_mkdir_dotl(dfid, name, mode, gid, &qid);
439 	if (err < 0)
440 		goto error;
441 
442 	/* instantiate inode and assign the unopened fid to the dentry */
443 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
444 		fid = p9_client_walk(dfid, 1, &name, 1);
445 		if (IS_ERR(fid)) {
446 			err = PTR_ERR(fid);
447 			P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
448 				err);
449 			fid = NULL;
450 			goto error;
451 		}
452 
453 		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
454 		if (IS_ERR(inode)) {
455 			err = PTR_ERR(inode);
456 			P9_DPRINTK(P9_DEBUG_VFS, "inode creation failed %d\n",
457 				err);
458 			goto error;
459 		}
460 		err = v9fs_fid_add(dentry, fid);
461 		if (err < 0)
462 			goto error;
463 		d_instantiate(dentry, inode);
464 		fid = NULL;
465 	} else {
466 		/*
467 		 * Not in cached mode. No need to populate
468 		 * inode with stat. We need to get an inode
469 		 * so that we can set the acl with dentry
470 		 */
471 		inode = v9fs_get_inode(dir->i_sb, mode, 0);
472 		if (IS_ERR(inode)) {
473 			err = PTR_ERR(inode);
474 			goto error;
475 		}
476 		d_instantiate(dentry, inode);
477 	}
478 	/* Now set the ACL based on the default value */
479 	v9fs_set_create_acl(dentry, &dacl, &pacl);
480 	inc_nlink(dir);
481 	v9fs_invalidate_inode_attr(dir);
482 error:
483 	if (fid)
484 		p9_client_clunk(fid);
485 	v9fs_set_create_acl(NULL, &dacl, &pacl);
486 	return err;
487 }
488 
489 static int
490 v9fs_vfs_getattr_dotl(struct vfsmount *mnt, struct dentry *dentry,
491 		 struct kstat *stat)
492 {
493 	int err;
494 	struct v9fs_session_info *v9ses;
495 	struct p9_fid *fid;
496 	struct p9_stat_dotl *st;
497 
498 	P9_DPRINTK(P9_DEBUG_VFS, "dentry: %p\n", dentry);
499 	err = -EPERM;
500 	v9ses = v9fs_dentry2v9ses(dentry);
501 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
502 		generic_fillattr(dentry->d_inode, stat);
503 		return 0;
504 	}
505 	fid = v9fs_fid_lookup(dentry);
506 	if (IS_ERR(fid))
507 		return PTR_ERR(fid);
508 
509 	/* Ask for all the fields in stat structure. Server will return
510 	 * whatever it supports
511 	 */
512 
513 	st = p9_client_getattr_dotl(fid, P9_STATS_ALL);
514 	if (IS_ERR(st))
515 		return PTR_ERR(st);
516 
517 	v9fs_stat2inode_dotl(st, dentry->d_inode);
518 	generic_fillattr(dentry->d_inode, stat);
519 	/* Change block size to what the server returned */
520 	stat->blksize = st->st_blksize;
521 
522 	kfree(st);
523 	return 0;
524 }
525 
526 /**
527  * v9fs_vfs_setattr_dotl - set file metadata
528  * @dentry: file whose metadata to set
529  * @iattr: metadata assignment structure
530  *
531  */
532 
533 int v9fs_vfs_setattr_dotl(struct dentry *dentry, struct iattr *iattr)
534 {
535 	int retval;
536 	struct v9fs_session_info *v9ses;
537 	struct p9_fid *fid;
538 	struct p9_iattr_dotl p9attr;
539 
540 	P9_DPRINTK(P9_DEBUG_VFS, "\n");
541 
542 	retval = inode_change_ok(dentry->d_inode, iattr);
543 	if (retval)
544 		return retval;
545 
546 	p9attr.valid = iattr->ia_valid;
547 	p9attr.mode = iattr->ia_mode;
548 	p9attr.uid = iattr->ia_uid;
549 	p9attr.gid = iattr->ia_gid;
550 	p9attr.size = iattr->ia_size;
551 	p9attr.atime_sec = iattr->ia_atime.tv_sec;
552 	p9attr.atime_nsec = iattr->ia_atime.tv_nsec;
553 	p9attr.mtime_sec = iattr->ia_mtime.tv_sec;
554 	p9attr.mtime_nsec = iattr->ia_mtime.tv_nsec;
555 
556 	retval = -EPERM;
557 	v9ses = v9fs_dentry2v9ses(dentry);
558 	fid = v9fs_fid_lookup(dentry);
559 	if (IS_ERR(fid))
560 		return PTR_ERR(fid);
561 
562 	/* Write all dirty data */
563 	if (S_ISREG(dentry->d_inode->i_mode))
564 		filemap_write_and_wait(dentry->d_inode->i_mapping);
565 
566 	retval = p9_client_setattr(fid, &p9attr);
567 	if (retval < 0)
568 		return retval;
569 
570 	if ((iattr->ia_valid & ATTR_SIZE) &&
571 	    iattr->ia_size != i_size_read(dentry->d_inode))
572 		truncate_setsize(dentry->d_inode, iattr->ia_size);
573 
574 	v9fs_invalidate_inode_attr(dentry->d_inode);
575 	setattr_copy(dentry->d_inode, iattr);
576 	mark_inode_dirty(dentry->d_inode);
577 	if (iattr->ia_valid & ATTR_MODE) {
578 		/* We also want to update ACL when we update mode bits */
579 		retval = v9fs_acl_chmod(dentry);
580 		if (retval < 0)
581 			return retval;
582 	}
583 	return 0;
584 }
585 
586 /**
587  * v9fs_stat2inode_dotl - populate an inode structure with stat info
588  * @stat: stat structure
589  * @inode: inode to populate
590  * @sb: superblock of filesystem
591  *
592  */
593 
594 void
595 v9fs_stat2inode_dotl(struct p9_stat_dotl *stat, struct inode *inode)
596 {
597 	mode_t mode;
598 	struct v9fs_inode *v9inode = V9FS_I(inode);
599 
600 	if ((stat->st_result_mask & P9_STATS_BASIC) == P9_STATS_BASIC) {
601 		inode->i_atime.tv_sec = stat->st_atime_sec;
602 		inode->i_atime.tv_nsec = stat->st_atime_nsec;
603 		inode->i_mtime.tv_sec = stat->st_mtime_sec;
604 		inode->i_mtime.tv_nsec = stat->st_mtime_nsec;
605 		inode->i_ctime.tv_sec = stat->st_ctime_sec;
606 		inode->i_ctime.tv_nsec = stat->st_ctime_nsec;
607 		inode->i_uid = stat->st_uid;
608 		inode->i_gid = stat->st_gid;
609 		set_nlink(inode, stat->st_nlink);
610 
611 		mode = stat->st_mode & S_IALLUGO;
612 		mode |= inode->i_mode & ~S_IALLUGO;
613 		inode->i_mode = mode;
614 
615 		i_size_write(inode, stat->st_size);
616 		inode->i_blocks = stat->st_blocks;
617 	} else {
618 		if (stat->st_result_mask & P9_STATS_ATIME) {
619 			inode->i_atime.tv_sec = stat->st_atime_sec;
620 			inode->i_atime.tv_nsec = stat->st_atime_nsec;
621 		}
622 		if (stat->st_result_mask & P9_STATS_MTIME) {
623 			inode->i_mtime.tv_sec = stat->st_mtime_sec;
624 			inode->i_mtime.tv_nsec = stat->st_mtime_nsec;
625 		}
626 		if (stat->st_result_mask & P9_STATS_CTIME) {
627 			inode->i_ctime.tv_sec = stat->st_ctime_sec;
628 			inode->i_ctime.tv_nsec = stat->st_ctime_nsec;
629 		}
630 		if (stat->st_result_mask & P9_STATS_UID)
631 			inode->i_uid = stat->st_uid;
632 		if (stat->st_result_mask & P9_STATS_GID)
633 			inode->i_gid = stat->st_gid;
634 		if (stat->st_result_mask & P9_STATS_NLINK)
635 			set_nlink(inode, stat->st_nlink);
636 		if (stat->st_result_mask & P9_STATS_MODE) {
637 			inode->i_mode = stat->st_mode;
638 			if ((S_ISBLK(inode->i_mode)) ||
639 						(S_ISCHR(inode->i_mode)))
640 				init_special_inode(inode, inode->i_mode,
641 								inode->i_rdev);
642 		}
643 		if (stat->st_result_mask & P9_STATS_RDEV)
644 			inode->i_rdev = new_decode_dev(stat->st_rdev);
645 		if (stat->st_result_mask & P9_STATS_SIZE)
646 			i_size_write(inode, stat->st_size);
647 		if (stat->st_result_mask & P9_STATS_BLOCKS)
648 			inode->i_blocks = stat->st_blocks;
649 	}
650 	if (stat->st_result_mask & P9_STATS_GEN)
651 		inode->i_generation = stat->st_gen;
652 
653 	/* Currently we don't support P9_STATS_BTIME and P9_STATS_DATA_VERSION
654 	 * because the inode structure does not have fields for them.
655 	 */
656 	v9inode->cache_validity &= ~V9FS_INO_INVALID_ATTR;
657 }
658 
659 static int
660 v9fs_vfs_symlink_dotl(struct inode *dir, struct dentry *dentry,
661 		const char *symname)
662 {
663 	int err;
664 	gid_t gid;
665 	char *name;
666 	struct p9_qid qid;
667 	struct inode *inode;
668 	struct p9_fid *dfid;
669 	struct p9_fid *fid = NULL;
670 	struct v9fs_session_info *v9ses;
671 
672 	name = (char *) dentry->d_name.name;
673 	P9_DPRINTK(P9_DEBUG_VFS, "v9fs_vfs_symlink_dotl : %lu,%s,%s\n",
674 			dir->i_ino, name, symname);
675 	v9ses = v9fs_inode2v9ses(dir);
676 
677 	dfid = v9fs_fid_lookup(dentry->d_parent);
678 	if (IS_ERR(dfid)) {
679 		err = PTR_ERR(dfid);
680 		P9_DPRINTK(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
681 		return err;
682 	}
683 
684 	gid = v9fs_get_fsgid_for_create(dir);
685 
686 	/* Server doesn't alter fid on TSYMLINK. Hence no need to clone it. */
687 	err = p9_client_symlink(dfid, name, (char *)symname, gid, &qid);
688 
689 	if (err < 0) {
690 		P9_DPRINTK(P9_DEBUG_VFS, "p9_client_symlink failed %d\n", err);
691 		goto error;
692 	}
693 
694 	v9fs_invalidate_inode_attr(dir);
695 	if (v9ses->cache) {
696 		/* Now walk from the parent so we can get an unopened fid. */
697 		fid = p9_client_walk(dfid, 1, &name, 1);
698 		if (IS_ERR(fid)) {
699 			err = PTR_ERR(fid);
700 			P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
701 					err);
702 			fid = NULL;
703 			goto error;
704 		}
705 
706 		/* instantiate inode and assign the unopened fid to dentry */
707 		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
708 		if (IS_ERR(inode)) {
709 			err = PTR_ERR(inode);
710 			P9_DPRINTK(P9_DEBUG_VFS, "inode creation failed %d\n",
711 					err);
712 			goto error;
713 		}
714 		err = v9fs_fid_add(dentry, fid);
715 		if (err < 0)
716 			goto error;
717 		d_instantiate(dentry, inode);
718 		fid = NULL;
719 	} else {
720 		/* Not in cached mode. No need to populate inode with stat */
721 		inode = v9fs_get_inode(dir->i_sb, S_IFLNK, 0);
722 		if (IS_ERR(inode)) {
723 			err = PTR_ERR(inode);
724 			goto error;
725 		}
726 		d_instantiate(dentry, inode);
727 	}
728 
729 error:
730 	if (fid)
731 		p9_client_clunk(fid);
732 
733 	return err;
734 }
735 
736 /**
737  * v9fs_vfs_link_dotl - create a hardlink for dotl
738  * @old_dentry: dentry for file to link to
739  * @dir: inode destination for new link
740  * @dentry: dentry for link
741  *
742  */
743 
744 static int
745 v9fs_vfs_link_dotl(struct dentry *old_dentry, struct inode *dir,
746 		struct dentry *dentry)
747 {
748 	int err;
749 	char *name;
750 	struct dentry *dir_dentry;
751 	struct p9_fid *dfid, *oldfid;
752 	struct v9fs_session_info *v9ses;
753 
754 	P9_DPRINTK(P9_DEBUG_VFS, "dir ino: %lu, old_name: %s, new_name: %s\n",
755 			dir->i_ino, old_dentry->d_name.name,
756 			dentry->d_name.name);
757 
758 	v9ses = v9fs_inode2v9ses(dir);
759 	dir_dentry = v9fs_dentry_from_dir_inode(dir);
760 	dfid = v9fs_fid_lookup(dir_dentry);
761 	if (IS_ERR(dfid))
762 		return PTR_ERR(dfid);
763 
764 	oldfid = v9fs_fid_lookup(old_dentry);
765 	if (IS_ERR(oldfid))
766 		return PTR_ERR(oldfid);
767 
768 	name = (char *) dentry->d_name.name;
769 
770 	err = p9_client_link(dfid, oldfid, (char *)dentry->d_name.name);
771 
772 	if (err < 0) {
773 		P9_DPRINTK(P9_DEBUG_VFS, "p9_client_link failed %d\n", err);
774 		return err;
775 	}
776 
777 	v9fs_invalidate_inode_attr(dir);
778 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
779 		/* Get the latest stat info from server. */
780 		struct p9_fid *fid;
781 		fid = v9fs_fid_lookup(old_dentry);
782 		if (IS_ERR(fid))
783 			return PTR_ERR(fid);
784 
785 		v9fs_refresh_inode_dotl(fid, old_dentry->d_inode);
786 	}
787 	ihold(old_dentry->d_inode);
788 	d_instantiate(dentry, old_dentry->d_inode);
789 
790 	return err;
791 }
792 
793 /**
794  * v9fs_vfs_mknod_dotl - create a special file
795  * @dir: inode destination for new link
796  * @dentry: dentry for file
797  * @mode: mode for creation
798  * @rdev: device associated with special file
799  *
800  */
801 static int
802 v9fs_vfs_mknod_dotl(struct inode *dir, struct dentry *dentry, int omode,
803 		dev_t rdev)
804 {
805 	int err;
806 	gid_t gid;
807 	char *name;
808 	umode_t mode;
809 	struct v9fs_session_info *v9ses;
810 	struct p9_fid *fid = NULL, *dfid = NULL;
811 	struct inode *inode;
812 	struct p9_qid qid;
813 	struct dentry *dir_dentry;
814 	struct posix_acl *dacl = NULL, *pacl = NULL;
815 
816 	P9_DPRINTK(P9_DEBUG_VFS,
817 		" %lu,%s mode: %x MAJOR: %u MINOR: %u\n", dir->i_ino,
818 		dentry->d_name.name, omode, MAJOR(rdev), MINOR(rdev));
819 
820 	if (!new_valid_dev(rdev))
821 		return -EINVAL;
822 
823 	v9ses = v9fs_inode2v9ses(dir);
824 	dir_dentry = v9fs_dentry_from_dir_inode(dir);
825 	dfid = v9fs_fid_lookup(dir_dentry);
826 	if (IS_ERR(dfid)) {
827 		err = PTR_ERR(dfid);
828 		P9_DPRINTK(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
829 		dfid = NULL;
830 		goto error;
831 	}
832 
833 	gid = v9fs_get_fsgid_for_create(dir);
834 	mode = omode;
835 	/* Update mode based on ACL value */
836 	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
837 	if (err) {
838 		P9_DPRINTK(P9_DEBUG_VFS,
839 			   "Failed to get acl values in mknod %d\n", err);
840 		goto error;
841 	}
842 	name = (char *) dentry->d_name.name;
843 
844 	err = p9_client_mknod_dotl(dfid, name, mode, rdev, gid, &qid);
845 	if (err < 0)
846 		goto error;
847 
848 	v9fs_invalidate_inode_attr(dir);
849 	/* instantiate inode and assign the unopened fid to the dentry */
850 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
851 		fid = p9_client_walk(dfid, 1, &name, 1);
852 		if (IS_ERR(fid)) {
853 			err = PTR_ERR(fid);
854 			P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
855 				err);
856 			fid = NULL;
857 			goto error;
858 		}
859 
860 		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
861 		if (IS_ERR(inode)) {
862 			err = PTR_ERR(inode);
863 			P9_DPRINTK(P9_DEBUG_VFS, "inode creation failed %d\n",
864 				err);
865 			goto error;
866 		}
867 		err = v9fs_fid_add(dentry, fid);
868 		if (err < 0)
869 			goto error;
870 		d_instantiate(dentry, inode);
871 		fid = NULL;
872 	} else {
873 		/*
874 		 * Not in cached mode. No need to populate inode with stat.
875 		 * socket syscall returns a fd, so we need instantiate
876 		 */
877 		inode = v9fs_get_inode(dir->i_sb, mode, rdev);
878 		if (IS_ERR(inode)) {
879 			err = PTR_ERR(inode);
880 			goto error;
881 		}
882 		d_instantiate(dentry, inode);
883 	}
884 	/* Now set the ACL based on the default value */
885 	v9fs_set_create_acl(dentry, &dacl, &pacl);
886 error:
887 	if (fid)
888 		p9_client_clunk(fid);
889 	v9fs_set_create_acl(NULL, &dacl, &pacl);
890 	return err;
891 }
892 
893 /**
894  * v9fs_vfs_follow_link_dotl - follow a symlink path
895  * @dentry: dentry for symlink
896  * @nd: nameidata
897  *
898  */
899 
900 static void *
901 v9fs_vfs_follow_link_dotl(struct dentry *dentry, struct nameidata *nd)
902 {
903 	int retval;
904 	struct p9_fid *fid;
905 	char *link = __getname();
906 	char *target;
907 
908 	P9_DPRINTK(P9_DEBUG_VFS, "%s\n", dentry->d_name.name);
909 
910 	if (!link) {
911 		link = ERR_PTR(-ENOMEM);
912 		goto ndset;
913 	}
914 	fid = v9fs_fid_lookup(dentry);
915 	if (IS_ERR(fid)) {
916 		__putname(link);
917 		link = ERR_CAST(fid);
918 		goto ndset;
919 	}
920 	retval = p9_client_readlink(fid, &target);
921 	if (!retval) {
922 		strcpy(link, target);
923 		kfree(target);
924 		goto ndset;
925 	}
926 	__putname(link);
927 	link = ERR_PTR(retval);
928 ndset:
929 	nd_set_link(nd, link);
930 	return NULL;
931 }
932 
933 int v9fs_refresh_inode_dotl(struct p9_fid *fid, struct inode *inode)
934 {
935 	loff_t i_size;
936 	struct p9_stat_dotl *st;
937 	struct v9fs_session_info *v9ses;
938 
939 	v9ses = v9fs_inode2v9ses(inode);
940 	st = p9_client_getattr_dotl(fid, P9_STATS_ALL);
941 	if (IS_ERR(st))
942 		return PTR_ERR(st);
943 	/*
944 	 * Don't update inode if the file type is different
945 	 */
946 	if ((inode->i_mode & S_IFMT) != (st->st_mode & S_IFMT))
947 		goto out;
948 
949 	spin_lock(&inode->i_lock);
950 	/*
951 	 * We don't want to refresh inode->i_size,
952 	 * because we may have cached data
953 	 */
954 	i_size = inode->i_size;
955 	v9fs_stat2inode_dotl(st, inode);
956 	if (v9ses->cache)
957 		inode->i_size = i_size;
958 	spin_unlock(&inode->i_lock);
959 out:
960 	kfree(st);
961 	return 0;
962 }
963 
964 const struct inode_operations v9fs_dir_inode_operations_dotl = {
965 	.create = v9fs_vfs_create_dotl,
966 	.lookup = v9fs_vfs_lookup,
967 	.link = v9fs_vfs_link_dotl,
968 	.symlink = v9fs_vfs_symlink_dotl,
969 	.unlink = v9fs_vfs_unlink,
970 	.mkdir = v9fs_vfs_mkdir_dotl,
971 	.rmdir = v9fs_vfs_rmdir,
972 	.mknod = v9fs_vfs_mknod_dotl,
973 	.rename = v9fs_vfs_rename,
974 	.getattr = v9fs_vfs_getattr_dotl,
975 	.setattr = v9fs_vfs_setattr_dotl,
976 	.setxattr = generic_setxattr,
977 	.getxattr = generic_getxattr,
978 	.removexattr = generic_removexattr,
979 	.listxattr = v9fs_listxattr,
980 	.get_acl = v9fs_iop_get_acl,
981 };
982 
983 const struct inode_operations v9fs_file_inode_operations_dotl = {
984 	.getattr = v9fs_vfs_getattr_dotl,
985 	.setattr = v9fs_vfs_setattr_dotl,
986 	.setxattr = generic_setxattr,
987 	.getxattr = generic_getxattr,
988 	.removexattr = generic_removexattr,
989 	.listxattr = v9fs_listxattr,
990 	.get_acl = v9fs_iop_get_acl,
991 };
992 
993 const struct inode_operations v9fs_symlink_inode_operations_dotl = {
994 	.readlink = generic_readlink,
995 	.follow_link = v9fs_vfs_follow_link_dotl,
996 	.put_link = v9fs_vfs_put_link,
997 	.getattr = v9fs_vfs_getattr_dotl,
998 	.setattr = v9fs_vfs_setattr_dotl,
999 	.setxattr = generic_setxattr,
1000 	.getxattr = generic_getxattr,
1001 	.removexattr = generic_removexattr,
1002 	.listxattr = v9fs_listxattr,
1003 };
1004