xref: /openbmc/linux/fs/9p/vfs_inode_dotl.c (revision 455f9726)
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 	return 1;
91 }
92 
93 /* Always get a new inode */
94 static int v9fs_test_new_inode_dotl(struct inode *inode, void *data)
95 {
96 	return 0;
97 }
98 
99 static int v9fs_set_inode_dotl(struct inode *inode,  void *data)
100 {
101 	struct v9fs_inode *v9inode = V9FS_I(inode);
102 	struct p9_stat_dotl *st = (struct p9_stat_dotl *)data;
103 
104 	memcpy(&v9inode->qid, &st->qid, sizeof(st->qid));
105 	inode->i_generation = st->st_gen;
106 	return 0;
107 }
108 
109 static struct inode *v9fs_qid_iget_dotl(struct super_block *sb,
110 					struct p9_qid *qid,
111 					struct p9_fid *fid,
112 					struct p9_stat_dotl *st,
113 					int new)
114 {
115 	int retval;
116 	unsigned long i_ino;
117 	struct inode *inode;
118 	struct v9fs_session_info *v9ses = sb->s_fs_info;
119 	int (*test)(struct inode *, void *);
120 
121 	if (new)
122 		test = v9fs_test_new_inode_dotl;
123 	else
124 		test = v9fs_test_inode_dotl;
125 
126 	i_ino = v9fs_qid2ino(qid);
127 	inode = iget5_locked(sb, i_ino, test, v9fs_set_inode_dotl, st);
128 	if (!inode)
129 		return ERR_PTR(-ENOMEM);
130 	if (!(inode->i_state & I_NEW))
131 		return inode;
132 	/*
133 	 * initialize the inode with the stat info
134 	 * FIXME!! we may need support for stale inodes
135 	 * later.
136 	 */
137 	inode->i_ino = i_ino;
138 	retval = v9fs_init_inode(v9ses, inode,
139 				 st->st_mode, new_decode_dev(st->st_rdev));
140 	if (retval)
141 		goto error;
142 
143 	v9fs_stat2inode_dotl(st, inode);
144 	v9fs_cache_inode_get_cookie(inode);
145 	retval = v9fs_get_acl(inode, fid);
146 	if (retval)
147 		goto error;
148 
149 	unlock_new_inode(inode);
150 	return inode;
151 error:
152 	unlock_new_inode(inode);
153 	iput(inode);
154 	return ERR_PTR(retval);
155 
156 }
157 
158 struct inode *
159 v9fs_inode_from_fid_dotl(struct v9fs_session_info *v9ses, struct p9_fid *fid,
160 			 struct super_block *sb, int new)
161 {
162 	struct p9_stat_dotl *st;
163 	struct inode *inode = NULL;
164 
165 	st = p9_client_getattr_dotl(fid, P9_STATS_BASIC | P9_STATS_GEN);
166 	if (IS_ERR(st))
167 		return ERR_CAST(st);
168 
169 	inode = v9fs_qid_iget_dotl(sb, &st->qid, fid, st, new);
170 	kfree(st);
171 	return inode;
172 }
173 
174 struct dotl_openflag_map {
175 	int open_flag;
176 	int dotl_flag;
177 };
178 
179 static int v9fs_mapped_dotl_flags(int flags)
180 {
181 	int i;
182 	int rflags = 0;
183 	struct dotl_openflag_map dotl_oflag_map[] = {
184 		{ O_CREAT,	P9_DOTL_CREATE },
185 		{ O_EXCL,	P9_DOTL_EXCL },
186 		{ O_NOCTTY,	P9_DOTL_NOCTTY },
187 		{ O_APPEND,	P9_DOTL_APPEND },
188 		{ O_NONBLOCK,	P9_DOTL_NONBLOCK },
189 		{ O_DSYNC,	P9_DOTL_DSYNC },
190 		{ FASYNC,	P9_DOTL_FASYNC },
191 		{ O_DIRECT,	P9_DOTL_DIRECT },
192 		{ O_LARGEFILE,	P9_DOTL_LARGEFILE },
193 		{ O_DIRECTORY,	P9_DOTL_DIRECTORY },
194 		{ O_NOFOLLOW,	P9_DOTL_NOFOLLOW },
195 		{ O_NOATIME,	P9_DOTL_NOATIME },
196 		{ O_CLOEXEC,	P9_DOTL_CLOEXEC },
197 		{ O_SYNC,	P9_DOTL_SYNC},
198 	};
199 	for (i = 0; i < ARRAY_SIZE(dotl_oflag_map); i++) {
200 		if (flags & dotl_oflag_map[i].open_flag)
201 			rflags |= dotl_oflag_map[i].dotl_flag;
202 	}
203 	return rflags;
204 }
205 
206 /**
207  * v9fs_open_to_dotl_flags- convert Linux specific open flags to
208  * plan 9 open flag.
209  * @flags: flags to convert
210  */
211 int v9fs_open_to_dotl_flags(int flags)
212 {
213 	int rflags = 0;
214 
215 	/*
216 	 * We have same bits for P9_DOTL_READONLY, P9_DOTL_WRONLY
217 	 * and P9_DOTL_NOACCESS
218 	 */
219 	rflags |= flags & O_ACCMODE;
220 	rflags |= v9fs_mapped_dotl_flags(flags);
221 
222 	return rflags;
223 }
224 
225 /**
226  * v9fs_vfs_create_dotl - VFS hook to create files for 9P2000.L protocol.
227  * @dir: directory inode that is being created
228  * @dentry:  dentry that is being deleted
229  * @omode: create permissions
230  *
231  */
232 
233 static int
234 v9fs_vfs_create_dotl(struct inode *dir, struct dentry *dentry, umode_t omode,
235 		bool excl)
236 {
237 	return v9fs_vfs_mknod_dotl(dir, dentry, omode, 0);
238 }
239 
240 static int
241 v9fs_vfs_atomic_open_dotl(struct inode *dir, struct dentry *dentry,
242 			  struct file *file, unsigned flags, umode_t omode,
243 			  int *opened)
244 {
245 	int err = 0;
246 	kgid_t gid;
247 	umode_t mode;
248 	char *name = NULL;
249 	struct p9_qid qid;
250 	struct inode *inode;
251 	struct p9_fid *fid = NULL;
252 	struct v9fs_inode *v9inode;
253 	struct p9_fid *dfid, *ofid, *inode_fid;
254 	struct v9fs_session_info *v9ses;
255 	struct posix_acl *pacl = NULL, *dacl = NULL;
256 	struct dentry *res = NULL;
257 
258 	if (d_unhashed(dentry)) {
259 		res = v9fs_vfs_lookup(dir, dentry, 0);
260 		if (IS_ERR(res))
261 			return PTR_ERR(res);
262 
263 		if (res)
264 			dentry = res;
265 	}
266 
267 	/* Only creates */
268 	if (!(flags & O_CREAT) || dentry->d_inode)
269 		return	finish_no_open(file, res);
270 
271 	v9ses = v9fs_inode2v9ses(dir);
272 
273 	name = (char *) dentry->d_name.name;
274 	p9_debug(P9_DEBUG_VFS, "name:%s flags:0x%x mode:0x%hx\n",
275 		 name, flags, omode);
276 
277 	dfid = v9fs_fid_lookup(dentry->d_parent);
278 	if (IS_ERR(dfid)) {
279 		err = PTR_ERR(dfid);
280 		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
281 		goto out;
282 	}
283 
284 	/* clone a fid to use for creation */
285 	ofid = p9_client_walk(dfid, 0, NULL, 1);
286 	if (IS_ERR(ofid)) {
287 		err = PTR_ERR(ofid);
288 		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
289 		goto out;
290 	}
291 
292 	gid = v9fs_get_fsgid_for_create(dir);
293 
294 	mode = omode;
295 	/* Update mode based on ACL value */
296 	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
297 	if (err) {
298 		p9_debug(P9_DEBUG_VFS, "Failed to get acl values in creat %d\n",
299 			 err);
300 		goto error;
301 	}
302 	err = p9_client_create_dotl(ofid, name, v9fs_open_to_dotl_flags(flags),
303 				    mode, gid, &qid);
304 	if (err < 0) {
305 		p9_debug(P9_DEBUG_VFS, "p9_client_open_dotl failed in creat %d\n",
306 			 err);
307 		goto error;
308 	}
309 	v9fs_invalidate_inode_attr(dir);
310 
311 	/* instantiate inode and assign the unopened fid to the dentry */
312 	fid = p9_client_walk(dfid, 1, &name, 1);
313 	if (IS_ERR(fid)) {
314 		err = PTR_ERR(fid);
315 		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
316 		fid = NULL;
317 		goto error;
318 	}
319 	inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
320 	if (IS_ERR(inode)) {
321 		err = PTR_ERR(inode);
322 		p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n", err);
323 		goto error;
324 	}
325 	/* Now set the ACL based on the default value */
326 	v9fs_set_create_acl(inode, fid, dacl, pacl);
327 
328 	v9fs_fid_add(dentry, fid);
329 	d_instantiate(dentry, inode);
330 
331 	v9inode = V9FS_I(inode);
332 	mutex_lock(&v9inode->v_mutex);
333 	if ((v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) &&
334 	    !v9inode->writeback_fid &&
335 	    ((flags & O_ACCMODE) != O_RDONLY)) {
336 		/*
337 		 * clone a fid and add it to writeback_fid
338 		 * we do it during open time instead of
339 		 * page dirty time via write_begin/page_mkwrite
340 		 * because we want write after unlink usecase
341 		 * to work.
342 		 */
343 		inode_fid = v9fs_writeback_fid(dentry);
344 		if (IS_ERR(inode_fid)) {
345 			err = PTR_ERR(inode_fid);
346 			mutex_unlock(&v9inode->v_mutex);
347 			goto err_clunk_old_fid;
348 		}
349 		v9inode->writeback_fid = (void *) inode_fid;
350 	}
351 	mutex_unlock(&v9inode->v_mutex);
352 	/* Since we are opening a file, assign the open fid to the file */
353 	err = finish_open(file, dentry, generic_file_open, opened);
354 	if (err)
355 		goto err_clunk_old_fid;
356 	file->private_data = ofid;
357 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
358 		v9fs_cache_inode_set_cookie(inode, file);
359 	*opened |= FILE_CREATED;
360 out:
361 	v9fs_put_acl(dacl, pacl);
362 	dput(res);
363 	return err;
364 
365 error:
366 	if (fid)
367 		p9_client_clunk(fid);
368 err_clunk_old_fid:
369 	if (ofid)
370 		p9_client_clunk(ofid);
371 	goto out;
372 }
373 
374 /**
375  * v9fs_vfs_mkdir_dotl - VFS mkdir hook to create a directory
376  * @dir:  inode that is being unlinked
377  * @dentry: dentry that is being unlinked
378  * @omode: mode for new directory
379  *
380  */
381 
382 static int v9fs_vfs_mkdir_dotl(struct inode *dir,
383 			       struct dentry *dentry, umode_t omode)
384 {
385 	int err;
386 	struct v9fs_session_info *v9ses;
387 	struct p9_fid *fid = NULL, *dfid = NULL;
388 	kgid_t gid;
389 	char *name;
390 	umode_t mode;
391 	struct inode *inode;
392 	struct p9_qid qid;
393 	struct dentry *dir_dentry;
394 	struct posix_acl *dacl = NULL, *pacl = NULL;
395 
396 	p9_debug(P9_DEBUG_VFS, "name %s\n", dentry->d_name.name);
397 	err = 0;
398 	v9ses = v9fs_inode2v9ses(dir);
399 
400 	omode |= S_IFDIR;
401 	if (dir->i_mode & S_ISGID)
402 		omode |= S_ISGID;
403 
404 	dir_dentry = dentry->d_parent;
405 	dfid = v9fs_fid_lookup(dir_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 = (char *) 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(struct vfsmount *mnt, struct dentry *dentry,
475 		 struct kstat *stat)
476 {
477 	struct v9fs_session_info *v9ses;
478 	struct p9_fid *fid;
479 	struct p9_stat_dotl *st;
480 
481 	p9_debug(P9_DEBUG_VFS, "dentry: %p\n", dentry);
482 	v9ses = v9fs_dentry2v9ses(dentry);
483 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
484 		generic_fillattr(dentry->d_inode, stat);
485 		return 0;
486 	}
487 	fid = v9fs_fid_lookup(dentry);
488 	if (IS_ERR(fid))
489 		return PTR_ERR(fid);
490 
491 	/* Ask for all the fields in stat structure. Server will return
492 	 * whatever it supports
493 	 */
494 
495 	st = p9_client_getattr_dotl(fid, P9_STATS_ALL);
496 	if (IS_ERR(st))
497 		return PTR_ERR(st);
498 
499 	v9fs_stat2inode_dotl(st, dentry->d_inode);
500 	generic_fillattr(dentry->d_inode, stat);
501 	/* Change block size to what the server returned */
502 	stat->blksize = st->st_blksize;
503 
504 	kfree(st);
505 	return 0;
506 }
507 
508 /*
509  * Attribute flags.
510  */
511 #define P9_ATTR_MODE		(1 << 0)
512 #define P9_ATTR_UID		(1 << 1)
513 #define P9_ATTR_GID		(1 << 2)
514 #define P9_ATTR_SIZE		(1 << 3)
515 #define P9_ATTR_ATIME		(1 << 4)
516 #define P9_ATTR_MTIME		(1 << 5)
517 #define P9_ATTR_CTIME		(1 << 6)
518 #define P9_ATTR_ATIME_SET	(1 << 7)
519 #define P9_ATTR_MTIME_SET	(1 << 8)
520 
521 struct dotl_iattr_map {
522 	int iattr_valid;
523 	int p9_iattr_valid;
524 };
525 
526 static int v9fs_mapped_iattr_valid(int iattr_valid)
527 {
528 	int i;
529 	int p9_iattr_valid = 0;
530 	struct dotl_iattr_map dotl_iattr_map[] = {
531 		{ ATTR_MODE,		P9_ATTR_MODE },
532 		{ ATTR_UID,		P9_ATTR_UID },
533 		{ ATTR_GID,		P9_ATTR_GID },
534 		{ ATTR_SIZE,		P9_ATTR_SIZE },
535 		{ ATTR_ATIME,		P9_ATTR_ATIME },
536 		{ ATTR_MTIME,		P9_ATTR_MTIME },
537 		{ ATTR_CTIME,		P9_ATTR_CTIME },
538 		{ ATTR_ATIME_SET,	P9_ATTR_ATIME_SET },
539 		{ ATTR_MTIME_SET,	P9_ATTR_MTIME_SET },
540 	};
541 	for (i = 0; i < ARRAY_SIZE(dotl_iattr_map); i++) {
542 		if (iattr_valid & dotl_iattr_map[i].iattr_valid)
543 			p9_iattr_valid |= dotl_iattr_map[i].p9_iattr_valid;
544 	}
545 	return p9_iattr_valid;
546 }
547 
548 /**
549  * v9fs_vfs_setattr_dotl - set file metadata
550  * @dentry: file whose metadata to set
551  * @iattr: metadata assignment structure
552  *
553  */
554 
555 int v9fs_vfs_setattr_dotl(struct dentry *dentry, struct iattr *iattr)
556 {
557 	int retval;
558 	struct p9_fid *fid;
559 	struct p9_iattr_dotl p9attr;
560 	struct inode *inode = dentry->d_inode;
561 
562 	p9_debug(P9_DEBUG_VFS, "\n");
563 
564 	retval = inode_change_ok(inode, iattr);
565 	if (retval)
566 		return retval;
567 
568 	p9attr.valid = v9fs_mapped_iattr_valid(iattr->ia_valid);
569 	p9attr.mode = iattr->ia_mode;
570 	p9attr.uid = iattr->ia_uid;
571 	p9attr.gid = iattr->ia_gid;
572 	p9attr.size = iattr->ia_size;
573 	p9attr.atime_sec = iattr->ia_atime.tv_sec;
574 	p9attr.atime_nsec = iattr->ia_atime.tv_nsec;
575 	p9attr.mtime_sec = iattr->ia_mtime.tv_sec;
576 	p9attr.mtime_nsec = iattr->ia_mtime.tv_nsec;
577 
578 	fid = v9fs_fid_lookup(dentry);
579 	if (IS_ERR(fid))
580 		return PTR_ERR(fid);
581 
582 	/* Write all dirty data */
583 	if (S_ISREG(inode->i_mode))
584 		filemap_write_and_wait(inode->i_mapping);
585 
586 	retval = p9_client_setattr(fid, &p9attr);
587 	if (retval < 0)
588 		return retval;
589 
590 	if ((iattr->ia_valid & ATTR_SIZE) &&
591 	    iattr->ia_size != i_size_read(inode))
592 		truncate_setsize(inode, iattr->ia_size);
593 
594 	v9fs_invalidate_inode_attr(inode);
595 	setattr_copy(inode, iattr);
596 	mark_inode_dirty(inode);
597 	if (iattr->ia_valid & ATTR_MODE) {
598 		/* We also want to update ACL when we update mode bits */
599 		retval = v9fs_acl_chmod(inode, fid);
600 		if (retval < 0)
601 			return retval;
602 	}
603 	return 0;
604 }
605 
606 /**
607  * v9fs_stat2inode_dotl - populate an inode structure with stat info
608  * @stat: stat structure
609  * @inode: inode to populate
610  *
611  */
612 
613 void
614 v9fs_stat2inode_dotl(struct p9_stat_dotl *stat, struct inode *inode)
615 {
616 	umode_t mode;
617 	struct v9fs_inode *v9inode = V9FS_I(inode);
618 
619 	if ((stat->st_result_mask & P9_STATS_BASIC) == P9_STATS_BASIC) {
620 		inode->i_atime.tv_sec = stat->st_atime_sec;
621 		inode->i_atime.tv_nsec = stat->st_atime_nsec;
622 		inode->i_mtime.tv_sec = stat->st_mtime_sec;
623 		inode->i_mtime.tv_nsec = stat->st_mtime_nsec;
624 		inode->i_ctime.tv_sec = stat->st_ctime_sec;
625 		inode->i_ctime.tv_nsec = stat->st_ctime_nsec;
626 		inode->i_uid = stat->st_uid;
627 		inode->i_gid = stat->st_gid;
628 		set_nlink(inode, stat->st_nlink);
629 
630 		mode = stat->st_mode & S_IALLUGO;
631 		mode |= inode->i_mode & ~S_IALLUGO;
632 		inode->i_mode = mode;
633 
634 		i_size_write(inode, stat->st_size);
635 		inode->i_blocks = stat->st_blocks;
636 	} else {
637 		if (stat->st_result_mask & P9_STATS_ATIME) {
638 			inode->i_atime.tv_sec = stat->st_atime_sec;
639 			inode->i_atime.tv_nsec = stat->st_atime_nsec;
640 		}
641 		if (stat->st_result_mask & P9_STATS_MTIME) {
642 			inode->i_mtime.tv_sec = stat->st_mtime_sec;
643 			inode->i_mtime.tv_nsec = stat->st_mtime_nsec;
644 		}
645 		if (stat->st_result_mask & P9_STATS_CTIME) {
646 			inode->i_ctime.tv_sec = stat->st_ctime_sec;
647 			inode->i_ctime.tv_nsec = stat->st_ctime_nsec;
648 		}
649 		if (stat->st_result_mask & P9_STATS_UID)
650 			inode->i_uid = stat->st_uid;
651 		if (stat->st_result_mask & P9_STATS_GID)
652 			inode->i_gid = stat->st_gid;
653 		if (stat->st_result_mask & P9_STATS_NLINK)
654 			set_nlink(inode, stat->st_nlink);
655 		if (stat->st_result_mask & P9_STATS_MODE) {
656 			inode->i_mode = stat->st_mode;
657 			if ((S_ISBLK(inode->i_mode)) ||
658 						(S_ISCHR(inode->i_mode)))
659 				init_special_inode(inode, inode->i_mode,
660 								inode->i_rdev);
661 		}
662 		if (stat->st_result_mask & P9_STATS_RDEV)
663 			inode->i_rdev = new_decode_dev(stat->st_rdev);
664 		if (stat->st_result_mask & P9_STATS_SIZE)
665 			i_size_write(inode, stat->st_size);
666 		if (stat->st_result_mask & P9_STATS_BLOCKS)
667 			inode->i_blocks = stat->st_blocks;
668 	}
669 	if (stat->st_result_mask & P9_STATS_GEN)
670 		inode->i_generation = stat->st_gen;
671 
672 	/* Currently we don't support P9_STATS_BTIME and P9_STATS_DATA_VERSION
673 	 * because the inode structure does not have fields for them.
674 	 */
675 	v9inode->cache_validity &= ~V9FS_INO_INVALID_ATTR;
676 }
677 
678 static int
679 v9fs_vfs_symlink_dotl(struct inode *dir, struct dentry *dentry,
680 		const char *symname)
681 {
682 	int err;
683 	kgid_t gid;
684 	char *name;
685 	struct p9_qid qid;
686 	struct inode *inode;
687 	struct p9_fid *dfid;
688 	struct p9_fid *fid = NULL;
689 	struct v9fs_session_info *v9ses;
690 
691 	name = (char *) dentry->d_name.name;
692 	p9_debug(P9_DEBUG_VFS, "%lu,%s,%s\n", dir->i_ino, name, symname);
693 	v9ses = v9fs_inode2v9ses(dir);
694 
695 	dfid = v9fs_fid_lookup(dentry->d_parent);
696 	if (IS_ERR(dfid)) {
697 		err = PTR_ERR(dfid);
698 		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
699 		return err;
700 	}
701 
702 	gid = v9fs_get_fsgid_for_create(dir);
703 
704 	/* Server doesn't alter fid on TSYMLINK. Hence no need to clone it. */
705 	err = p9_client_symlink(dfid, name, (char *)symname, gid, &qid);
706 
707 	if (err < 0) {
708 		p9_debug(P9_DEBUG_VFS, "p9_client_symlink failed %d\n", err);
709 		goto error;
710 	}
711 
712 	v9fs_invalidate_inode_attr(dir);
713 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
714 		/* Now walk from the parent so we can get an unopened fid. */
715 		fid = p9_client_walk(dfid, 1, &name, 1);
716 		if (IS_ERR(fid)) {
717 			err = PTR_ERR(fid);
718 			p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
719 				 err);
720 			fid = NULL;
721 			goto error;
722 		}
723 
724 		/* instantiate inode and assign the unopened fid to dentry */
725 		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
726 		if (IS_ERR(inode)) {
727 			err = PTR_ERR(inode);
728 			p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n",
729 				 err);
730 			goto error;
731 		}
732 		v9fs_fid_add(dentry, fid);
733 		d_instantiate(dentry, inode);
734 		fid = NULL;
735 		err = 0;
736 	} else {
737 		/* Not in cached mode. No need to populate inode with stat */
738 		inode = v9fs_get_inode(dir->i_sb, S_IFLNK, 0);
739 		if (IS_ERR(inode)) {
740 			err = PTR_ERR(inode);
741 			goto error;
742 		}
743 		d_instantiate(dentry, inode);
744 	}
745 
746 error:
747 	if (fid)
748 		p9_client_clunk(fid);
749 
750 	return err;
751 }
752 
753 /**
754  * v9fs_vfs_link_dotl - create a hardlink for dotl
755  * @old_dentry: dentry for file to link to
756  * @dir: inode destination for new link
757  * @dentry: dentry for link
758  *
759  */
760 
761 static int
762 v9fs_vfs_link_dotl(struct dentry *old_dentry, struct inode *dir,
763 		struct dentry *dentry)
764 {
765 	int err;
766 	struct dentry *dir_dentry;
767 	struct p9_fid *dfid, *oldfid;
768 	struct v9fs_session_info *v9ses;
769 
770 	p9_debug(P9_DEBUG_VFS, "dir ino: %lu, old_name: %s, new_name: %s\n",
771 		 dir->i_ino, old_dentry->d_name.name, dentry->d_name.name);
772 
773 	v9ses = v9fs_inode2v9ses(dir);
774 	dir_dentry = dentry->d_parent;
775 	dfid = v9fs_fid_lookup(dir_dentry);
776 	if (IS_ERR(dfid))
777 		return PTR_ERR(dfid);
778 
779 	oldfid = v9fs_fid_lookup(old_dentry);
780 	if (IS_ERR(oldfid))
781 		return PTR_ERR(oldfid);
782 
783 	err = p9_client_link(dfid, oldfid, (char *)dentry->d_name.name);
784 
785 	if (err < 0) {
786 		p9_debug(P9_DEBUG_VFS, "p9_client_link failed %d\n", err);
787 		return err;
788 	}
789 
790 	v9fs_invalidate_inode_attr(dir);
791 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
792 		/* Get the latest stat info from server. */
793 		struct p9_fid *fid;
794 		fid = v9fs_fid_lookup(old_dentry);
795 		if (IS_ERR(fid))
796 			return PTR_ERR(fid);
797 
798 		v9fs_refresh_inode_dotl(fid, old_dentry->d_inode);
799 	}
800 	ihold(old_dentry->d_inode);
801 	d_instantiate(dentry, old_dentry->d_inode);
802 
803 	return err;
804 }
805 
806 /**
807  * v9fs_vfs_mknod_dotl - create a special file
808  * @dir: inode destination for new link
809  * @dentry: dentry for file
810  * @omode: mode for creation
811  * @rdev: device associated with special file
812  *
813  */
814 static int
815 v9fs_vfs_mknod_dotl(struct inode *dir, struct dentry *dentry, umode_t omode,
816 		dev_t rdev)
817 {
818 	int err;
819 	kgid_t gid;
820 	char *name;
821 	umode_t mode;
822 	struct v9fs_session_info *v9ses;
823 	struct p9_fid *fid = NULL, *dfid = NULL;
824 	struct inode *inode;
825 	struct p9_qid qid;
826 	struct dentry *dir_dentry;
827 	struct posix_acl *dacl = NULL, *pacl = NULL;
828 
829 	p9_debug(P9_DEBUG_VFS, " %lu,%s mode: %hx MAJOR: %u MINOR: %u\n",
830 		 dir->i_ino, dentry->d_name.name, omode,
831 		 MAJOR(rdev), MINOR(rdev));
832 
833 	if (!new_valid_dev(rdev))
834 		return -EINVAL;
835 
836 	v9ses = v9fs_inode2v9ses(dir);
837 	dir_dentry = dentry->d_parent;
838 	dfid = v9fs_fid_lookup(dir_dentry);
839 	if (IS_ERR(dfid)) {
840 		err = PTR_ERR(dfid);
841 		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
842 		dfid = NULL;
843 		goto error;
844 	}
845 
846 	gid = v9fs_get_fsgid_for_create(dir);
847 	mode = omode;
848 	/* Update mode based on ACL value */
849 	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
850 	if (err) {
851 		p9_debug(P9_DEBUG_VFS, "Failed to get acl values in mknod %d\n",
852 			 err);
853 		goto error;
854 	}
855 	name = (char *) dentry->d_name.name;
856 
857 	err = p9_client_mknod_dotl(dfid, name, mode, rdev, gid, &qid);
858 	if (err < 0)
859 		goto error;
860 
861 	v9fs_invalidate_inode_attr(dir);
862 	fid = p9_client_walk(dfid, 1, &name, 1);
863 	if (IS_ERR(fid)) {
864 		err = PTR_ERR(fid);
865 		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
866 			 err);
867 		fid = NULL;
868 		goto error;
869 	}
870 
871 	/* instantiate inode and assign the unopened fid to the dentry */
872 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
873 		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
874 		if (IS_ERR(inode)) {
875 			err = PTR_ERR(inode);
876 			p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n",
877 				 err);
878 			goto error;
879 		}
880 		v9fs_set_create_acl(inode, fid, dacl, pacl);
881 		v9fs_fid_add(dentry, fid);
882 		d_instantiate(dentry, inode);
883 		fid = NULL;
884 		err = 0;
885 	} else {
886 		/*
887 		 * Not in cached mode. No need to populate inode with stat.
888 		 * socket syscall returns a fd, so we need instantiate
889 		 */
890 		inode = v9fs_get_inode(dir->i_sb, mode, rdev);
891 		if (IS_ERR(inode)) {
892 			err = PTR_ERR(inode);
893 			goto error;
894 		}
895 		v9fs_set_create_acl(inode, fid, dacl, pacl);
896 		d_instantiate(dentry, inode);
897 	}
898 error:
899 	if (fid)
900 		p9_client_clunk(fid);
901 	v9fs_put_acl(dacl, pacl);
902 	return err;
903 }
904 
905 /**
906  * v9fs_vfs_follow_link_dotl - follow a symlink path
907  * @dentry: dentry for symlink
908  * @nd: nameidata
909  *
910  */
911 
912 static void *
913 v9fs_vfs_follow_link_dotl(struct dentry *dentry, struct nameidata *nd)
914 {
915 	int retval;
916 	struct p9_fid *fid;
917 	char *link = __getname();
918 	char *target;
919 
920 	p9_debug(P9_DEBUG_VFS, "%s\n", dentry->d_name.name);
921 
922 	if (!link) {
923 		link = ERR_PTR(-ENOMEM);
924 		goto ndset;
925 	}
926 	fid = v9fs_fid_lookup(dentry);
927 	if (IS_ERR(fid)) {
928 		__putname(link);
929 		link = ERR_CAST(fid);
930 		goto ndset;
931 	}
932 	retval = p9_client_readlink(fid, &target);
933 	if (!retval) {
934 		strcpy(link, target);
935 		kfree(target);
936 		goto ndset;
937 	}
938 	__putname(link);
939 	link = ERR_PTR(retval);
940 ndset:
941 	nd_set_link(nd, link);
942 	return NULL;
943 }
944 
945 int v9fs_refresh_inode_dotl(struct p9_fid *fid, struct inode *inode)
946 {
947 	loff_t i_size;
948 	struct p9_stat_dotl *st;
949 	struct v9fs_session_info *v9ses;
950 
951 	v9ses = v9fs_inode2v9ses(inode);
952 	st = p9_client_getattr_dotl(fid, P9_STATS_ALL);
953 	if (IS_ERR(st))
954 		return PTR_ERR(st);
955 	/*
956 	 * Don't update inode if the file type is different
957 	 */
958 	if ((inode->i_mode & S_IFMT) != (st->st_mode & S_IFMT))
959 		goto out;
960 
961 	spin_lock(&inode->i_lock);
962 	/*
963 	 * We don't want to refresh inode->i_size,
964 	 * because we may have cached data
965 	 */
966 	i_size = inode->i_size;
967 	v9fs_stat2inode_dotl(st, inode);
968 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
969 		inode->i_size = i_size;
970 	spin_unlock(&inode->i_lock);
971 out:
972 	kfree(st);
973 	return 0;
974 }
975 
976 const struct inode_operations v9fs_dir_inode_operations_dotl = {
977 	.create = v9fs_vfs_create_dotl,
978 	.atomic_open = v9fs_vfs_atomic_open_dotl,
979 	.lookup = v9fs_vfs_lookup,
980 	.link = v9fs_vfs_link_dotl,
981 	.symlink = v9fs_vfs_symlink_dotl,
982 	.unlink = v9fs_vfs_unlink,
983 	.mkdir = v9fs_vfs_mkdir_dotl,
984 	.rmdir = v9fs_vfs_rmdir,
985 	.mknod = v9fs_vfs_mknod_dotl,
986 	.rename = v9fs_vfs_rename,
987 	.getattr = v9fs_vfs_getattr_dotl,
988 	.setattr = v9fs_vfs_setattr_dotl,
989 	.setxattr = generic_setxattr,
990 	.getxattr = generic_getxattr,
991 	.removexattr = generic_removexattr,
992 	.listxattr = v9fs_listxattr,
993 	.get_acl = v9fs_iop_get_acl,
994 };
995 
996 const struct inode_operations v9fs_file_inode_operations_dotl = {
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 	.get_acl = v9fs_iop_get_acl,
1004 };
1005 
1006 const struct inode_operations v9fs_symlink_inode_operations_dotl = {
1007 	.readlink = generic_readlink,
1008 	.follow_link = v9fs_vfs_follow_link_dotl,
1009 	.put_link = v9fs_vfs_put_link,
1010 	.getattr = v9fs_vfs_getattr_dotl,
1011 	.setattr = v9fs_vfs_setattr_dotl,
1012 	.setxattr = generic_setxattr,
1013 	.getxattr = generic_getxattr,
1014 	.removexattr = generic_removexattr,
1015 	.listxattr = v9fs_listxattr,
1016 };
1017