xref: /openbmc/linux/fs/9p/vfs_inode_dotl.c (revision 930beb5a)
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  * @mode: 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 && !v9inode->writeback_fid &&
334 	    ((flags & O_ACCMODE) != O_RDONLY)) {
335 		/*
336 		 * clone a fid and add it to writeback_fid
337 		 * we do it during open time instead of
338 		 * page dirty time via write_begin/page_mkwrite
339 		 * because we want write after unlink usecase
340 		 * to work.
341 		 */
342 		inode_fid = v9fs_writeback_fid(dentry);
343 		if (IS_ERR(inode_fid)) {
344 			err = PTR_ERR(inode_fid);
345 			mutex_unlock(&v9inode->v_mutex);
346 			goto err_clunk_old_fid;
347 		}
348 		v9inode->writeback_fid = (void *) inode_fid;
349 	}
350 	mutex_unlock(&v9inode->v_mutex);
351 	/* Since we are opening a file, assign the open fid to the file */
352 	err = finish_open(file, dentry, generic_file_open, opened);
353 	if (err)
354 		goto err_clunk_old_fid;
355 	file->private_data = ofid;
356 	if (v9ses->cache)
357 		v9fs_cache_inode_set_cookie(inode, file);
358 	*opened |= FILE_CREATED;
359 out:
360 	v9fs_put_acl(dacl, pacl);
361 	dput(res);
362 	return err;
363 
364 error:
365 	if (fid)
366 		p9_client_clunk(fid);
367 err_clunk_old_fid:
368 	if (ofid)
369 		p9_client_clunk(ofid);
370 	goto out;
371 }
372 
373 /**
374  * v9fs_vfs_mkdir_dotl - VFS mkdir hook to create a directory
375  * @dir:  inode that is being unlinked
376  * @dentry: dentry that is being unlinked
377  * @mode: mode for new directory
378  *
379  */
380 
381 static int v9fs_vfs_mkdir_dotl(struct inode *dir,
382 			       struct dentry *dentry, umode_t omode)
383 {
384 	int err;
385 	struct v9fs_session_info *v9ses;
386 	struct p9_fid *fid = NULL, *dfid = NULL;
387 	kgid_t gid;
388 	char *name;
389 	umode_t mode;
390 	struct inode *inode;
391 	struct p9_qid qid;
392 	struct dentry *dir_dentry;
393 	struct posix_acl *dacl = NULL, *pacl = NULL;
394 
395 	p9_debug(P9_DEBUG_VFS, "name %s\n", dentry->d_name.name);
396 	err = 0;
397 	v9ses = v9fs_inode2v9ses(dir);
398 
399 	omode |= S_IFDIR;
400 	if (dir->i_mode & S_ISGID)
401 		omode |= S_ISGID;
402 
403 	dir_dentry = dentry->d_parent;
404 	dfid = v9fs_fid_lookup(dir_dentry);
405 	if (IS_ERR(dfid)) {
406 		err = PTR_ERR(dfid);
407 		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
408 		dfid = NULL;
409 		goto error;
410 	}
411 
412 	gid = v9fs_get_fsgid_for_create(dir);
413 	mode = omode;
414 	/* Update mode based on ACL value */
415 	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
416 	if (err) {
417 		p9_debug(P9_DEBUG_VFS, "Failed to get acl values in mkdir %d\n",
418 			 err);
419 		goto error;
420 	}
421 	name = (char *) dentry->d_name.name;
422 	err = p9_client_mkdir_dotl(dfid, name, mode, gid, &qid);
423 	if (err < 0)
424 		goto error;
425 
426 	fid = p9_client_walk(dfid, 1, &name, 1);
427 	if (IS_ERR(fid)) {
428 		err = PTR_ERR(fid);
429 		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
430 			 err);
431 		fid = NULL;
432 		goto error;
433 	}
434 
435 	/* instantiate inode and assign the unopened fid to the dentry */
436 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
437 		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
438 		if (IS_ERR(inode)) {
439 			err = PTR_ERR(inode);
440 			p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n",
441 				 err);
442 			goto error;
443 		}
444 		v9fs_fid_add(dentry, fid);
445 		v9fs_set_create_acl(inode, fid, dacl, pacl);
446 		d_instantiate(dentry, inode);
447 		fid = NULL;
448 		err = 0;
449 	} else {
450 		/*
451 		 * Not in cached mode. No need to populate
452 		 * inode with stat. We need to get an inode
453 		 * so that we can set the acl with dentry
454 		 */
455 		inode = v9fs_get_inode(dir->i_sb, mode, 0);
456 		if (IS_ERR(inode)) {
457 			err = PTR_ERR(inode);
458 			goto error;
459 		}
460 		v9fs_set_create_acl(inode, fid, dacl, pacl);
461 		d_instantiate(dentry, inode);
462 	}
463 	inc_nlink(dir);
464 	v9fs_invalidate_inode_attr(dir);
465 error:
466 	if (fid)
467 		p9_client_clunk(fid);
468 	v9fs_put_acl(dacl, pacl);
469 	return err;
470 }
471 
472 static int
473 v9fs_vfs_getattr_dotl(struct vfsmount *mnt, struct dentry *dentry,
474 		 struct kstat *stat)
475 {
476 	int err;
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 	err = -EPERM;
483 	v9ses = v9fs_dentry2v9ses(dentry);
484 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
485 		generic_fillattr(dentry->d_inode, 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, dentry->d_inode);
501 	generic_fillattr(dentry->d_inode, 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 v9fs_session_info *v9ses;
560 	struct p9_fid *fid;
561 	struct p9_iattr_dotl p9attr;
562 	struct inode *inode = dentry->d_inode;
563 
564 	p9_debug(P9_DEBUG_VFS, "\n");
565 
566 	retval = inode_change_ok(inode, iattr);
567 	if (retval)
568 		return retval;
569 
570 	p9attr.valid = v9fs_mapped_iattr_valid(iattr->ia_valid);
571 	p9attr.mode = iattr->ia_mode;
572 	p9attr.uid = iattr->ia_uid;
573 	p9attr.gid = iattr->ia_gid;
574 	p9attr.size = iattr->ia_size;
575 	p9attr.atime_sec = iattr->ia_atime.tv_sec;
576 	p9attr.atime_nsec = iattr->ia_atime.tv_nsec;
577 	p9attr.mtime_sec = iattr->ia_mtime.tv_sec;
578 	p9attr.mtime_nsec = iattr->ia_mtime.tv_nsec;
579 
580 	retval = -EPERM;
581 	v9ses = v9fs_dentry2v9ses(dentry);
582 	fid = v9fs_fid_lookup(dentry);
583 	if (IS_ERR(fid))
584 		return PTR_ERR(fid);
585 
586 	/* Write all dirty data */
587 	if (S_ISREG(inode->i_mode))
588 		filemap_write_and_wait(inode->i_mapping);
589 
590 	retval = p9_client_setattr(fid, &p9attr);
591 	if (retval < 0)
592 		return retval;
593 
594 	if ((iattr->ia_valid & ATTR_SIZE) &&
595 	    iattr->ia_size != i_size_read(inode))
596 		truncate_setsize(inode, iattr->ia_size);
597 
598 	v9fs_invalidate_inode_attr(inode);
599 	setattr_copy(inode, iattr);
600 	mark_inode_dirty(inode);
601 	if (iattr->ia_valid & ATTR_MODE) {
602 		/* We also want to update ACL when we update mode bits */
603 		retval = v9fs_acl_chmod(inode, fid);
604 		if (retval < 0)
605 			return retval;
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  * @sb: superblock of filesystem
615  *
616  */
617 
618 void
619 v9fs_stat2inode_dotl(struct p9_stat_dotl *stat, struct inode *inode)
620 {
621 	umode_t mode;
622 	struct v9fs_inode *v9inode = V9FS_I(inode);
623 
624 	if ((stat->st_result_mask & P9_STATS_BASIC) == P9_STATS_BASIC) {
625 		inode->i_atime.tv_sec = stat->st_atime_sec;
626 		inode->i_atime.tv_nsec = stat->st_atime_nsec;
627 		inode->i_mtime.tv_sec = stat->st_mtime_sec;
628 		inode->i_mtime.tv_nsec = stat->st_mtime_nsec;
629 		inode->i_ctime.tv_sec = stat->st_ctime_sec;
630 		inode->i_ctime.tv_nsec = stat->st_ctime_nsec;
631 		inode->i_uid = stat->st_uid;
632 		inode->i_gid = stat->st_gid;
633 		set_nlink(inode, stat->st_nlink);
634 
635 		mode = stat->st_mode & S_IALLUGO;
636 		mode |= inode->i_mode & ~S_IALLUGO;
637 		inode->i_mode = mode;
638 
639 		i_size_write(inode, stat->st_size);
640 		inode->i_blocks = stat->st_blocks;
641 	} else {
642 		if (stat->st_result_mask & P9_STATS_ATIME) {
643 			inode->i_atime.tv_sec = stat->st_atime_sec;
644 			inode->i_atime.tv_nsec = stat->st_atime_nsec;
645 		}
646 		if (stat->st_result_mask & P9_STATS_MTIME) {
647 			inode->i_mtime.tv_sec = stat->st_mtime_sec;
648 			inode->i_mtime.tv_nsec = stat->st_mtime_nsec;
649 		}
650 		if (stat->st_result_mask & P9_STATS_CTIME) {
651 			inode->i_ctime.tv_sec = stat->st_ctime_sec;
652 			inode->i_ctime.tv_nsec = stat->st_ctime_nsec;
653 		}
654 		if (stat->st_result_mask & P9_STATS_UID)
655 			inode->i_uid = stat->st_uid;
656 		if (stat->st_result_mask & P9_STATS_GID)
657 			inode->i_gid = stat->st_gid;
658 		if (stat->st_result_mask & P9_STATS_NLINK)
659 			set_nlink(inode, stat->st_nlink);
660 		if (stat->st_result_mask & P9_STATS_MODE) {
661 			inode->i_mode = stat->st_mode;
662 			if ((S_ISBLK(inode->i_mode)) ||
663 						(S_ISCHR(inode->i_mode)))
664 				init_special_inode(inode, inode->i_mode,
665 								inode->i_rdev);
666 		}
667 		if (stat->st_result_mask & P9_STATS_RDEV)
668 			inode->i_rdev = new_decode_dev(stat->st_rdev);
669 		if (stat->st_result_mask & P9_STATS_SIZE)
670 			i_size_write(inode, stat->st_size);
671 		if (stat->st_result_mask & P9_STATS_BLOCKS)
672 			inode->i_blocks = stat->st_blocks;
673 	}
674 	if (stat->st_result_mask & P9_STATS_GEN)
675 		inode->i_generation = stat->st_gen;
676 
677 	/* Currently we don't support P9_STATS_BTIME and P9_STATS_DATA_VERSION
678 	 * because the inode structure does not have fields for them.
679 	 */
680 	v9inode->cache_validity &= ~V9FS_INO_INVALID_ATTR;
681 }
682 
683 static int
684 v9fs_vfs_symlink_dotl(struct inode *dir, struct dentry *dentry,
685 		const char *symname)
686 {
687 	int err;
688 	kgid_t gid;
689 	char *name;
690 	struct p9_qid qid;
691 	struct inode *inode;
692 	struct p9_fid *dfid;
693 	struct p9_fid *fid = NULL;
694 	struct v9fs_session_info *v9ses;
695 
696 	name = (char *) dentry->d_name.name;
697 	p9_debug(P9_DEBUG_VFS, "%lu,%s,%s\n", dir->i_ino, name, symname);
698 	v9ses = v9fs_inode2v9ses(dir);
699 
700 	dfid = v9fs_fid_lookup(dentry->d_parent);
701 	if (IS_ERR(dfid)) {
702 		err = PTR_ERR(dfid);
703 		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
704 		return err;
705 	}
706 
707 	gid = v9fs_get_fsgid_for_create(dir);
708 
709 	/* Server doesn't alter fid on TSYMLINK. Hence no need to clone it. */
710 	err = p9_client_symlink(dfid, name, (char *)symname, gid, &qid);
711 
712 	if (err < 0) {
713 		p9_debug(P9_DEBUG_VFS, "p9_client_symlink failed %d\n", err);
714 		goto error;
715 	}
716 
717 	v9fs_invalidate_inode_attr(dir);
718 	if (v9ses->cache) {
719 		/* Now walk from the parent so we can get an unopened fid. */
720 		fid = p9_client_walk(dfid, 1, &name, 1);
721 		if (IS_ERR(fid)) {
722 			err = PTR_ERR(fid);
723 			p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
724 				 err);
725 			fid = NULL;
726 			goto error;
727 		}
728 
729 		/* instantiate inode and assign the unopened fid to dentry */
730 		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
731 		if (IS_ERR(inode)) {
732 			err = PTR_ERR(inode);
733 			p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n",
734 				 err);
735 			goto error;
736 		}
737 		v9fs_fid_add(dentry, fid);
738 		d_instantiate(dentry, inode);
739 		fid = NULL;
740 		err = 0;
741 	} else {
742 		/* Not in cached mode. No need to populate inode with stat */
743 		inode = v9fs_get_inode(dir->i_sb, S_IFLNK, 0);
744 		if (IS_ERR(inode)) {
745 			err = PTR_ERR(inode);
746 			goto error;
747 		}
748 		d_instantiate(dentry, inode);
749 	}
750 
751 error:
752 	if (fid)
753 		p9_client_clunk(fid);
754 
755 	return err;
756 }
757 
758 /**
759  * v9fs_vfs_link_dotl - create a hardlink for dotl
760  * @old_dentry: dentry for file to link to
761  * @dir: inode destination for new link
762  * @dentry: dentry for link
763  *
764  */
765 
766 static int
767 v9fs_vfs_link_dotl(struct dentry *old_dentry, struct inode *dir,
768 		struct dentry *dentry)
769 {
770 	int err;
771 	char *name;
772 	struct dentry *dir_dentry;
773 	struct p9_fid *dfid, *oldfid;
774 	struct v9fs_session_info *v9ses;
775 
776 	p9_debug(P9_DEBUG_VFS, "dir ino: %lu, old_name: %s, new_name: %s\n",
777 		 dir->i_ino, old_dentry->d_name.name, dentry->d_name.name);
778 
779 	v9ses = v9fs_inode2v9ses(dir);
780 	dir_dentry = dentry->d_parent;
781 	dfid = v9fs_fid_lookup(dir_dentry);
782 	if (IS_ERR(dfid))
783 		return PTR_ERR(dfid);
784 
785 	oldfid = v9fs_fid_lookup(old_dentry);
786 	if (IS_ERR(oldfid))
787 		return PTR_ERR(oldfid);
788 
789 	name = (char *) dentry->d_name.name;
790 
791 	err = p9_client_link(dfid, oldfid, (char *)dentry->d_name.name);
792 
793 	if (err < 0) {
794 		p9_debug(P9_DEBUG_VFS, "p9_client_link failed %d\n", err);
795 		return err;
796 	}
797 
798 	v9fs_invalidate_inode_attr(dir);
799 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
800 		/* Get the latest stat info from server. */
801 		struct p9_fid *fid;
802 		fid = v9fs_fid_lookup(old_dentry);
803 		if (IS_ERR(fid))
804 			return PTR_ERR(fid);
805 
806 		v9fs_refresh_inode_dotl(fid, old_dentry->d_inode);
807 	}
808 	ihold(old_dentry->d_inode);
809 	d_instantiate(dentry, old_dentry->d_inode);
810 
811 	return err;
812 }
813 
814 /**
815  * v9fs_vfs_mknod_dotl - create a special file
816  * @dir: inode destination for new link
817  * @dentry: dentry for file
818  * @mode: mode for creation
819  * @rdev: device associated with special file
820  *
821  */
822 static int
823 v9fs_vfs_mknod_dotl(struct inode *dir, struct dentry *dentry, umode_t omode,
824 		dev_t rdev)
825 {
826 	int err;
827 	kgid_t gid;
828 	char *name;
829 	umode_t mode;
830 	struct v9fs_session_info *v9ses;
831 	struct p9_fid *fid = NULL, *dfid = NULL;
832 	struct inode *inode;
833 	struct p9_qid qid;
834 	struct dentry *dir_dentry;
835 	struct posix_acl *dacl = NULL, *pacl = NULL;
836 
837 	p9_debug(P9_DEBUG_VFS, " %lu,%s mode: %hx MAJOR: %u MINOR: %u\n",
838 		 dir->i_ino, dentry->d_name.name, omode,
839 		 MAJOR(rdev), MINOR(rdev));
840 
841 	if (!new_valid_dev(rdev))
842 		return -EINVAL;
843 
844 	v9ses = v9fs_inode2v9ses(dir);
845 	dir_dentry = dentry->d_parent;
846 	dfid = v9fs_fid_lookup(dir_dentry);
847 	if (IS_ERR(dfid)) {
848 		err = PTR_ERR(dfid);
849 		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
850 		dfid = NULL;
851 		goto error;
852 	}
853 
854 	gid = v9fs_get_fsgid_for_create(dir);
855 	mode = omode;
856 	/* Update mode based on ACL value */
857 	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
858 	if (err) {
859 		p9_debug(P9_DEBUG_VFS, "Failed to get acl values in mknod %d\n",
860 			 err);
861 		goto error;
862 	}
863 	name = (char *) dentry->d_name.name;
864 
865 	err = p9_client_mknod_dotl(dfid, name, mode, rdev, gid, &qid);
866 	if (err < 0)
867 		goto error;
868 
869 	v9fs_invalidate_inode_attr(dir);
870 	fid = p9_client_walk(dfid, 1, &name, 1);
871 	if (IS_ERR(fid)) {
872 		err = PTR_ERR(fid);
873 		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
874 			 err);
875 		fid = NULL;
876 		goto error;
877 	}
878 
879 	/* instantiate inode and assign the unopened fid to the dentry */
880 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
881 		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
882 		if (IS_ERR(inode)) {
883 			err = PTR_ERR(inode);
884 			p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n",
885 				 err);
886 			goto error;
887 		}
888 		v9fs_set_create_acl(inode, fid, dacl, pacl);
889 		v9fs_fid_add(dentry, fid);
890 		d_instantiate(dentry, inode);
891 		fid = NULL;
892 		err = 0;
893 	} else {
894 		/*
895 		 * Not in cached mode. No need to populate inode with stat.
896 		 * socket syscall returns a fd, so we need instantiate
897 		 */
898 		inode = v9fs_get_inode(dir->i_sb, mode, rdev);
899 		if (IS_ERR(inode)) {
900 			err = PTR_ERR(inode);
901 			goto error;
902 		}
903 		v9fs_set_create_acl(inode, fid, dacl, pacl);
904 		d_instantiate(dentry, inode);
905 	}
906 error:
907 	if (fid)
908 		p9_client_clunk(fid);
909 	v9fs_put_acl(dacl, pacl);
910 	return err;
911 }
912 
913 /**
914  * v9fs_vfs_follow_link_dotl - follow a symlink path
915  * @dentry: dentry for symlink
916  * @nd: nameidata
917  *
918  */
919 
920 static void *
921 v9fs_vfs_follow_link_dotl(struct dentry *dentry, struct nameidata *nd)
922 {
923 	int retval;
924 	struct p9_fid *fid;
925 	char *link = __getname();
926 	char *target;
927 
928 	p9_debug(P9_DEBUG_VFS, "%s\n", dentry->d_name.name);
929 
930 	if (!link) {
931 		link = ERR_PTR(-ENOMEM);
932 		goto ndset;
933 	}
934 	fid = v9fs_fid_lookup(dentry);
935 	if (IS_ERR(fid)) {
936 		__putname(link);
937 		link = ERR_CAST(fid);
938 		goto ndset;
939 	}
940 	retval = p9_client_readlink(fid, &target);
941 	if (!retval) {
942 		strcpy(link, target);
943 		kfree(target);
944 		goto ndset;
945 	}
946 	__putname(link);
947 	link = ERR_PTR(retval);
948 ndset:
949 	nd_set_link(nd, link);
950 	return NULL;
951 }
952 
953 int v9fs_refresh_inode_dotl(struct p9_fid *fid, struct inode *inode)
954 {
955 	loff_t i_size;
956 	struct p9_stat_dotl *st;
957 	struct v9fs_session_info *v9ses;
958 
959 	v9ses = v9fs_inode2v9ses(inode);
960 	st = p9_client_getattr_dotl(fid, P9_STATS_ALL);
961 	if (IS_ERR(st))
962 		return PTR_ERR(st);
963 	/*
964 	 * Don't update inode if the file type is different
965 	 */
966 	if ((inode->i_mode & S_IFMT) != (st->st_mode & S_IFMT))
967 		goto out;
968 
969 	spin_lock(&inode->i_lock);
970 	/*
971 	 * We don't want to refresh inode->i_size,
972 	 * because we may have cached data
973 	 */
974 	i_size = inode->i_size;
975 	v9fs_stat2inode_dotl(st, inode);
976 	if (v9ses->cache)
977 		inode->i_size = i_size;
978 	spin_unlock(&inode->i_lock);
979 out:
980 	kfree(st);
981 	return 0;
982 }
983 
984 const struct inode_operations v9fs_dir_inode_operations_dotl = {
985 	.create = v9fs_vfs_create_dotl,
986 	.atomic_open = v9fs_vfs_atomic_open_dotl,
987 	.lookup = v9fs_vfs_lookup,
988 	.link = v9fs_vfs_link_dotl,
989 	.symlink = v9fs_vfs_symlink_dotl,
990 	.unlink = v9fs_vfs_unlink,
991 	.mkdir = v9fs_vfs_mkdir_dotl,
992 	.rmdir = v9fs_vfs_rmdir,
993 	.mknod = v9fs_vfs_mknod_dotl,
994 	.rename = v9fs_vfs_rename,
995 	.getattr = v9fs_vfs_getattr_dotl,
996 	.setattr = v9fs_vfs_setattr_dotl,
997 	.setxattr = generic_setxattr,
998 	.getxattr = generic_getxattr,
999 	.removexattr = generic_removexattr,
1000 	.listxattr = v9fs_listxattr,
1001 	.get_acl = v9fs_iop_get_acl,
1002 };
1003 
1004 const struct inode_operations v9fs_file_inode_operations_dotl = {
1005 	.getattr = v9fs_vfs_getattr_dotl,
1006 	.setattr = v9fs_vfs_setattr_dotl,
1007 	.setxattr = generic_setxattr,
1008 	.getxattr = generic_getxattr,
1009 	.removexattr = generic_removexattr,
1010 	.listxattr = v9fs_listxattr,
1011 	.get_acl = v9fs_iop_get_acl,
1012 };
1013 
1014 const struct inode_operations v9fs_symlink_inode_operations_dotl = {
1015 	.readlink = generic_readlink,
1016 	.follow_link = v9fs_vfs_follow_link_dotl,
1017 	.put_link = v9fs_vfs_put_link,
1018 	.getattr = v9fs_vfs_getattr_dotl,
1019 	.setattr = v9fs_vfs_setattr_dotl,
1020 	.setxattr = generic_setxattr,
1021 	.getxattr = generic_getxattr,
1022 	.removexattr = generic_removexattr,
1023 	.listxattr = v9fs_listxattr,
1024 };
1025