xref: /openbmc/linux/fs/9p/vfs_inode.c (revision baa7eb025ab14f3cba2e35c0a8648f9c9f01d24f)
1 /*
2  *  linux/fs/9p/vfs_inode.c
3  *
4  * This file contains vfs inode ops for the 9P2000 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 const struct inode_operations v9fs_dir_inode_operations;
51 static const struct inode_operations v9fs_dir_inode_operations_dotu;
52 static const struct inode_operations v9fs_dir_inode_operations_dotl;
53 static const struct inode_operations v9fs_file_inode_operations;
54 static const struct inode_operations v9fs_file_inode_operations_dotl;
55 static const struct inode_operations v9fs_symlink_inode_operations;
56 static const struct inode_operations v9fs_symlink_inode_operations_dotl;
57 
58 static int
59 v9fs_vfs_mknod_dotl(struct inode *dir, struct dentry *dentry, int omode,
60 		    dev_t rdev);
61 
62 /**
63  * unixmode2p9mode - convert unix mode bits to plan 9
64  * @v9ses: v9fs session information
65  * @mode: mode to convert
66  *
67  */
68 
69 static int unixmode2p9mode(struct v9fs_session_info *v9ses, int mode)
70 {
71 	int res;
72 	res = mode & 0777;
73 	if (S_ISDIR(mode))
74 		res |= P9_DMDIR;
75 	if (v9fs_proto_dotu(v9ses)) {
76 		if (S_ISLNK(mode))
77 			res |= P9_DMSYMLINK;
78 		if (v9ses->nodev == 0) {
79 			if (S_ISSOCK(mode))
80 				res |= P9_DMSOCKET;
81 			if (S_ISFIFO(mode))
82 				res |= P9_DMNAMEDPIPE;
83 			if (S_ISBLK(mode))
84 				res |= P9_DMDEVICE;
85 			if (S_ISCHR(mode))
86 				res |= P9_DMDEVICE;
87 		}
88 
89 		if ((mode & S_ISUID) == S_ISUID)
90 			res |= P9_DMSETUID;
91 		if ((mode & S_ISGID) == S_ISGID)
92 			res |= P9_DMSETGID;
93 		if ((mode & S_ISVTX) == S_ISVTX)
94 			res |= P9_DMSETVTX;
95 		if ((mode & P9_DMLINK))
96 			res |= P9_DMLINK;
97 	}
98 
99 	return res;
100 }
101 
102 /**
103  * p9mode2unixmode- convert plan9 mode bits to unix mode bits
104  * @v9ses: v9fs session information
105  * @mode: mode to convert
106  *
107  */
108 
109 static int p9mode2unixmode(struct v9fs_session_info *v9ses, int mode)
110 {
111 	int res;
112 
113 	res = mode & 0777;
114 
115 	if ((mode & P9_DMDIR) == P9_DMDIR)
116 		res |= S_IFDIR;
117 	else if ((mode & P9_DMSYMLINK) && (v9fs_proto_dotu(v9ses)))
118 		res |= S_IFLNK;
119 	else if ((mode & P9_DMSOCKET) && (v9fs_proto_dotu(v9ses))
120 		 && (v9ses->nodev == 0))
121 		res |= S_IFSOCK;
122 	else if ((mode & P9_DMNAMEDPIPE) && (v9fs_proto_dotu(v9ses))
123 		 && (v9ses->nodev == 0))
124 		res |= S_IFIFO;
125 	else if ((mode & P9_DMDEVICE) && (v9fs_proto_dotu(v9ses))
126 		 && (v9ses->nodev == 0))
127 		res |= S_IFBLK;
128 	else
129 		res |= S_IFREG;
130 
131 	if (v9fs_proto_dotu(v9ses)) {
132 		if ((mode & P9_DMSETUID) == P9_DMSETUID)
133 			res |= S_ISUID;
134 
135 		if ((mode & P9_DMSETGID) == P9_DMSETGID)
136 			res |= S_ISGID;
137 
138 		if ((mode & P9_DMSETVTX) == P9_DMSETVTX)
139 			res |= S_ISVTX;
140 	}
141 
142 	return res;
143 }
144 
145 /**
146  * v9fs_uflags2omode- convert posix open flags to plan 9 mode bits
147  * @uflags: flags to convert
148  * @extended: if .u extensions are active
149  */
150 
151 int v9fs_uflags2omode(int uflags, int extended)
152 {
153 	int ret;
154 
155 	ret = 0;
156 	switch (uflags&3) {
157 	default:
158 	case O_RDONLY:
159 		ret = P9_OREAD;
160 		break;
161 
162 	case O_WRONLY:
163 		ret = P9_OWRITE;
164 		break;
165 
166 	case O_RDWR:
167 		ret = P9_ORDWR;
168 		break;
169 	}
170 
171 	if (uflags & O_TRUNC)
172 		ret |= P9_OTRUNC;
173 
174 	if (extended) {
175 		if (uflags & O_EXCL)
176 			ret |= P9_OEXCL;
177 
178 		if (uflags & O_APPEND)
179 			ret |= P9_OAPPEND;
180 	}
181 
182 	return ret;
183 }
184 
185 /**
186  * v9fs_blank_wstat - helper function to setup a 9P stat structure
187  * @wstat: structure to initialize
188  *
189  */
190 
191 void
192 v9fs_blank_wstat(struct p9_wstat *wstat)
193 {
194 	wstat->type = ~0;
195 	wstat->dev = ~0;
196 	wstat->qid.type = ~0;
197 	wstat->qid.version = ~0;
198 	*((long long *)&wstat->qid.path) = ~0;
199 	wstat->mode = ~0;
200 	wstat->atime = ~0;
201 	wstat->mtime = ~0;
202 	wstat->length = ~0;
203 	wstat->name = NULL;
204 	wstat->uid = NULL;
205 	wstat->gid = NULL;
206 	wstat->muid = NULL;
207 	wstat->n_uid = ~0;
208 	wstat->n_gid = ~0;
209 	wstat->n_muid = ~0;
210 	wstat->extension = NULL;
211 }
212 
213 #ifdef CONFIG_9P_FSCACHE
214 /**
215  * v9fs_alloc_inode - helper function to allocate an inode
216  * This callback is executed before setting up the inode so that we
217  * can associate a vcookie with each inode.
218  *
219  */
220 
221 struct inode *v9fs_alloc_inode(struct super_block *sb)
222 {
223 	struct v9fs_cookie *vcookie;
224 	vcookie = (struct v9fs_cookie *)kmem_cache_alloc(vcookie_cache,
225 							 GFP_KERNEL);
226 	if (!vcookie)
227 		return NULL;
228 
229 	vcookie->fscache = NULL;
230 	vcookie->qid = NULL;
231 	spin_lock_init(&vcookie->lock);
232 	return &vcookie->inode;
233 }
234 
235 /**
236  * v9fs_destroy_inode - destroy an inode
237  *
238  */
239 
240 void v9fs_destroy_inode(struct inode *inode)
241 {
242 	kmem_cache_free(vcookie_cache, v9fs_inode2cookie(inode));
243 }
244 #endif
245 
246 /**
247  * v9fs_get_fsgid_for_create - Helper function to get the gid for creating a
248  * new file system object. This checks the S_ISGID to determine the owning
249  * group of the new file system object.
250  */
251 
252 static gid_t v9fs_get_fsgid_for_create(struct inode *dir_inode)
253 {
254 	BUG_ON(dir_inode == NULL);
255 
256 	if (dir_inode->i_mode & S_ISGID) {
257 		/* set_gid bit is set.*/
258 		return dir_inode->i_gid;
259 	}
260 	return current_fsgid();
261 }
262 
263 /**
264  * v9fs_dentry_from_dir_inode - helper function to get the dentry from
265  * dir inode.
266  *
267  */
268 
269 static struct dentry *v9fs_dentry_from_dir_inode(struct inode *inode)
270 {
271 	struct dentry *dentry;
272 
273 	spin_lock(&dcache_lock);
274 	/* Directory should have only one entry. */
275 	BUG_ON(S_ISDIR(inode->i_mode) && !list_is_singular(&inode->i_dentry));
276 	dentry = list_entry(inode->i_dentry.next, struct dentry, d_alias);
277 	spin_unlock(&dcache_lock);
278 	return dentry;
279 }
280 
281 /**
282  * v9fs_get_inode - helper function to setup an inode
283  * @sb: superblock
284  * @mode: mode to setup inode with
285  *
286  */
287 
288 struct inode *v9fs_get_inode(struct super_block *sb, int mode)
289 {
290 	int err;
291 	struct inode *inode;
292 	struct v9fs_session_info *v9ses = sb->s_fs_info;
293 
294 	P9_DPRINTK(P9_DEBUG_VFS, "super block: %p mode: %o\n", sb, mode);
295 
296 	inode = new_inode(sb);
297 	if (!inode) {
298 		P9_EPRINTK(KERN_WARNING, "Problem allocating inode\n");
299 		return ERR_PTR(-ENOMEM);
300 	}
301 
302 	inode_init_owner(inode, NULL, mode);
303 	inode->i_blocks = 0;
304 	inode->i_rdev = 0;
305 	inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
306 	inode->i_mapping->a_ops = &v9fs_addr_operations;
307 
308 	switch (mode & S_IFMT) {
309 	case S_IFIFO:
310 	case S_IFBLK:
311 	case S_IFCHR:
312 	case S_IFSOCK:
313 		if (v9fs_proto_dotl(v9ses)) {
314 			inode->i_op = &v9fs_file_inode_operations_dotl;
315 			inode->i_fop = &v9fs_file_operations_dotl;
316 		} else if (v9fs_proto_dotu(v9ses)) {
317 			inode->i_op = &v9fs_file_inode_operations;
318 			inode->i_fop = &v9fs_file_operations;
319 		} else {
320 			P9_DPRINTK(P9_DEBUG_ERROR,
321 				   "special files without extended mode\n");
322 			err = -EINVAL;
323 			goto error;
324 		}
325 		init_special_inode(inode, inode->i_mode, inode->i_rdev);
326 		break;
327 	case S_IFREG:
328 		if (v9fs_proto_dotl(v9ses)) {
329 			inode->i_op = &v9fs_file_inode_operations_dotl;
330 			inode->i_fop = &v9fs_file_operations_dotl;
331 		} else {
332 			inode->i_op = &v9fs_file_inode_operations;
333 			inode->i_fop = &v9fs_file_operations;
334 		}
335 
336 		break;
337 
338 	case S_IFLNK:
339 		if (!v9fs_proto_dotu(v9ses) && !v9fs_proto_dotl(v9ses)) {
340 			P9_DPRINTK(P9_DEBUG_ERROR, "extended modes used with "
341 						"legacy protocol.\n");
342 			err = -EINVAL;
343 			goto error;
344 		}
345 
346 		if (v9fs_proto_dotl(v9ses))
347 			inode->i_op = &v9fs_symlink_inode_operations_dotl;
348 		else
349 			inode->i_op = &v9fs_symlink_inode_operations;
350 
351 		break;
352 	case S_IFDIR:
353 		inc_nlink(inode);
354 		if (v9fs_proto_dotl(v9ses))
355 			inode->i_op = &v9fs_dir_inode_operations_dotl;
356 		else if (v9fs_proto_dotu(v9ses))
357 			inode->i_op = &v9fs_dir_inode_operations_dotu;
358 		else
359 			inode->i_op = &v9fs_dir_inode_operations;
360 
361 		if (v9fs_proto_dotl(v9ses))
362 			inode->i_fop = &v9fs_dir_operations_dotl;
363 		else
364 			inode->i_fop = &v9fs_dir_operations;
365 
366 		break;
367 	default:
368 		P9_DPRINTK(P9_DEBUG_ERROR, "BAD mode 0x%x S_IFMT 0x%x\n",
369 			   mode, mode & S_IFMT);
370 		err = -EINVAL;
371 		goto error;
372 	}
373 
374 	return inode;
375 
376 error:
377 	iput(inode);
378 	return ERR_PTR(err);
379 }
380 
381 /*
382 static struct v9fs_fid*
383 v9fs_clone_walk(struct v9fs_session_info *v9ses, u32 fid, struct dentry *dentry)
384 {
385 	int err;
386 	int nfid;
387 	struct v9fs_fid *ret;
388 	struct v9fs_fcall *fcall;
389 
390 	nfid = v9fs_get_idpool(&v9ses->fidpool);
391 	if (nfid < 0) {
392 		eprintk(KERN_WARNING, "no free fids available\n");
393 		return ERR_PTR(-ENOSPC);
394 	}
395 
396 	err = v9fs_t_walk(v9ses, fid, nfid, (char *) dentry->d_name.name,
397 		&fcall);
398 
399 	if (err < 0) {
400 		if (fcall && fcall->id == RWALK)
401 			goto clunk_fid;
402 
403 		PRINT_FCALL_ERROR("walk error", fcall);
404 		v9fs_put_idpool(nfid, &v9ses->fidpool);
405 		goto error;
406 	}
407 
408 	kfree(fcall);
409 	fcall = NULL;
410 	ret = v9fs_fid_create(v9ses, nfid);
411 	if (!ret) {
412 		err = -ENOMEM;
413 		goto clunk_fid;
414 	}
415 
416 	err = v9fs_fid_insert(ret, dentry);
417 	if (err < 0) {
418 		v9fs_fid_destroy(ret);
419 		goto clunk_fid;
420 	}
421 
422 	return ret;
423 
424 clunk_fid:
425 	v9fs_t_clunk(v9ses, nfid);
426 
427 error:
428 	kfree(fcall);
429 	return ERR_PTR(err);
430 }
431 */
432 
433 
434 /**
435  * v9fs_clear_inode - release an inode
436  * @inode: inode to release
437  *
438  */
439 void v9fs_evict_inode(struct inode *inode)
440 {
441 	truncate_inode_pages(inode->i_mapping, 0);
442 	end_writeback(inode);
443 	filemap_fdatawrite(inode->i_mapping);
444 
445 #ifdef CONFIG_9P_FSCACHE
446 	v9fs_cache_inode_put_cookie(inode);
447 #endif
448 }
449 
450 static struct inode *
451 v9fs_inode(struct v9fs_session_info *v9ses, struct p9_fid *fid,
452 	struct super_block *sb)
453 {
454 	int err, umode;
455 	struct inode *ret = NULL;
456 	struct p9_wstat *st;
457 
458 	st = p9_client_stat(fid);
459 	if (IS_ERR(st))
460 		return ERR_CAST(st);
461 
462 	umode = p9mode2unixmode(v9ses, st->mode);
463 	ret = v9fs_get_inode(sb, umode);
464 	if (IS_ERR(ret)) {
465 		err = PTR_ERR(ret);
466 		goto error;
467 	}
468 
469 	v9fs_stat2inode(st, ret, sb);
470 	ret->i_ino = v9fs_qid2ino(&st->qid);
471 
472 #ifdef CONFIG_9P_FSCACHE
473 	v9fs_vcookie_set_qid(ret, &st->qid);
474 	v9fs_cache_inode_get_cookie(ret);
475 #endif
476 	p9stat_free(st);
477 	kfree(st);
478 	return ret;
479 error:
480 	p9stat_free(st);
481 	kfree(st);
482 	return ERR_PTR(err);
483 }
484 
485 static struct inode *
486 v9fs_inode_dotl(struct v9fs_session_info *v9ses, struct p9_fid *fid,
487 	struct super_block *sb)
488 {
489 	struct inode *ret = NULL;
490 	int err;
491 	struct p9_stat_dotl *st;
492 
493 	st = p9_client_getattr_dotl(fid, P9_STATS_BASIC);
494 	if (IS_ERR(st))
495 		return ERR_CAST(st);
496 
497 	ret = v9fs_get_inode(sb, st->st_mode);
498 	if (IS_ERR(ret)) {
499 		err = PTR_ERR(ret);
500 		goto error;
501 	}
502 
503 	v9fs_stat2inode_dotl(st, ret);
504 	ret->i_ino = v9fs_qid2ino(&st->qid);
505 #ifdef CONFIG_9P_FSCACHE
506 	v9fs_vcookie_set_qid(ret, &st->qid);
507 	v9fs_cache_inode_get_cookie(ret);
508 #endif
509 	err = v9fs_get_acl(ret, fid);
510 	if (err) {
511 		iput(ret);
512 		goto error;
513 	}
514 	kfree(st);
515 	return ret;
516 error:
517 	kfree(st);
518 	return ERR_PTR(err);
519 }
520 
521 /**
522  * v9fs_inode_from_fid - Helper routine to populate an inode by
523  * issuing a attribute request
524  * @v9ses: session information
525  * @fid: fid to issue attribute request for
526  * @sb: superblock on which to create inode
527  *
528  */
529 static inline struct inode *
530 v9fs_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid,
531 			struct super_block *sb)
532 {
533 	if (v9fs_proto_dotl(v9ses))
534 		return v9fs_inode_dotl(v9ses, fid, sb);
535 	else
536 		return v9fs_inode(v9ses, fid, sb);
537 }
538 
539 /**
540  * v9fs_remove - helper function to remove files and directories
541  * @dir: directory inode that is being deleted
542  * @file:  dentry that is being deleted
543  * @rmdir: removing a directory
544  *
545  */
546 
547 static int v9fs_remove(struct inode *dir, struct dentry *file, int rmdir)
548 {
549 	int retval;
550 	struct inode *file_inode;
551 	struct p9_fid *v9fid;
552 
553 	P9_DPRINTK(P9_DEBUG_VFS, "inode: %p dentry: %p rmdir: %d\n", dir, file,
554 		rmdir);
555 
556 	file_inode = file->d_inode;
557 	v9fid = v9fs_fid_clone(file);
558 	if (IS_ERR(v9fid))
559 		return PTR_ERR(v9fid);
560 
561 	retval = p9_client_remove(v9fid);
562 	if (!retval)
563 		drop_nlink(file_inode);
564 	return retval;
565 }
566 
567 /**
568  * v9fs_create - Create a file
569  * @v9ses: session information
570  * @dir: directory that dentry is being created in
571  * @dentry:  dentry that is being created
572  * @extension: 9p2000.u extension string to support devices, etc.
573  * @perm: create permissions
574  * @mode: open mode
575  *
576  */
577 static struct p9_fid *
578 v9fs_create(struct v9fs_session_info *v9ses, struct inode *dir,
579 		struct dentry *dentry, char *extension, u32 perm, u8 mode)
580 {
581 	int err;
582 	char *name;
583 	struct p9_fid *dfid, *ofid, *fid;
584 	struct inode *inode;
585 
586 	P9_DPRINTK(P9_DEBUG_VFS, "name %s\n", dentry->d_name.name);
587 
588 	err = 0;
589 	ofid = NULL;
590 	fid = NULL;
591 	name = (char *) dentry->d_name.name;
592 	dfid = v9fs_fid_lookup(dentry->d_parent);
593 	if (IS_ERR(dfid)) {
594 		err = PTR_ERR(dfid);
595 		P9_DPRINTK(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
596 		return ERR_PTR(err);
597 	}
598 
599 	/* clone a fid to use for creation */
600 	ofid = p9_client_walk(dfid, 0, NULL, 1);
601 	if (IS_ERR(ofid)) {
602 		err = PTR_ERR(ofid);
603 		P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
604 		return ERR_PTR(err);
605 	}
606 
607 	err = p9_client_fcreate(ofid, name, perm, mode, extension);
608 	if (err < 0) {
609 		P9_DPRINTK(P9_DEBUG_VFS, "p9_client_fcreate failed %d\n", err);
610 		goto error;
611 	}
612 
613 	/* now walk from the parent so we can get unopened fid */
614 	fid = p9_client_walk(dfid, 1, &name, 1);
615 	if (IS_ERR(fid)) {
616 		err = PTR_ERR(fid);
617 		P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
618 		fid = NULL;
619 		goto error;
620 	}
621 
622 	/* instantiate inode and assign the unopened fid to the dentry */
623 	inode = v9fs_inode_from_fid(v9ses, fid, dir->i_sb);
624 	if (IS_ERR(inode)) {
625 		err = PTR_ERR(inode);
626 		P9_DPRINTK(P9_DEBUG_VFS, "inode creation failed %d\n", err);
627 		goto error;
628 	}
629 
630 	if (v9ses->cache)
631 		dentry->d_op = &v9fs_cached_dentry_operations;
632 	else
633 		dentry->d_op = &v9fs_dentry_operations;
634 
635 	d_instantiate(dentry, inode);
636 	err = v9fs_fid_add(dentry, fid);
637 	if (err < 0)
638 		goto error;
639 
640 	return ofid;
641 
642 error:
643 	if (ofid)
644 		p9_client_clunk(ofid);
645 
646 	if (fid)
647 		p9_client_clunk(fid);
648 
649 	return ERR_PTR(err);
650 }
651 
652 /**
653  * v9fs_vfs_create_dotl - VFS hook to create files for 9P2000.L protocol.
654  * @dir: directory inode that is being created
655  * @dentry:  dentry that is being deleted
656  * @mode: create permissions
657  * @nd: path information
658  *
659  */
660 
661 static int
662 v9fs_vfs_create_dotl(struct inode *dir, struct dentry *dentry, int omode,
663 		struct nameidata *nd)
664 {
665 	int err = 0;
666 	char *name = NULL;
667 	gid_t gid;
668 	int flags;
669 	mode_t mode;
670 	struct v9fs_session_info *v9ses;
671 	struct p9_fid *fid = NULL;
672 	struct p9_fid *dfid, *ofid;
673 	struct file *filp;
674 	struct p9_qid qid;
675 	struct inode *inode;
676 	struct posix_acl *pacl = NULL, *dacl = NULL;
677 
678 	v9ses = v9fs_inode2v9ses(dir);
679 	if (nd && nd->flags & LOOKUP_OPEN)
680 		flags = nd->intent.open.flags - 1;
681 	else {
682 		/*
683 		 * create call without LOOKUP_OPEN is due
684 		 * to mknod of regular files. So use mknod
685 		 * operation.
686 		 */
687 		return v9fs_vfs_mknod_dotl(dir, dentry, omode, 0);
688 	}
689 
690 	name = (char *) dentry->d_name.name;
691 	P9_DPRINTK(P9_DEBUG_VFS, "v9fs_vfs_create_dotl: name:%s flags:0x%x "
692 			"mode:0x%x\n", name, flags, omode);
693 
694 	dfid = v9fs_fid_lookup(dentry->d_parent);
695 	if (IS_ERR(dfid)) {
696 		err = PTR_ERR(dfid);
697 		P9_DPRINTK(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
698 		return err;
699 	}
700 
701 	/* clone a fid to use for creation */
702 	ofid = p9_client_walk(dfid, 0, NULL, 1);
703 	if (IS_ERR(ofid)) {
704 		err = PTR_ERR(ofid);
705 		P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
706 		return err;
707 	}
708 
709 	gid = v9fs_get_fsgid_for_create(dir);
710 
711 	mode = omode;
712 	/* Update mode based on ACL value */
713 	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
714 	if (err) {
715 		P9_DPRINTK(P9_DEBUG_VFS,
716 			   "Failed to get acl values in creat %d\n", err);
717 		goto error;
718 	}
719 	err = p9_client_create_dotl(ofid, name, flags, mode, gid, &qid);
720 	if (err < 0) {
721 		P9_DPRINTK(P9_DEBUG_VFS,
722 				"p9_client_open_dotl failed in creat %d\n",
723 				err);
724 		goto error;
725 	}
726 	/* instantiate inode and assign the unopened fid to the dentry */
727 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE ||
728 	    (nd && nd->flags & LOOKUP_OPEN)) {
729 		fid = p9_client_walk(dfid, 1, &name, 1);
730 		if (IS_ERR(fid)) {
731 			err = PTR_ERR(fid);
732 			P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
733 				err);
734 			fid = NULL;
735 			goto error;
736 		}
737 
738 		inode = v9fs_inode_from_fid(v9ses, fid, dir->i_sb);
739 		if (IS_ERR(inode)) {
740 			err = PTR_ERR(inode);
741 			P9_DPRINTK(P9_DEBUG_VFS, "inode creation failed %d\n",
742 				err);
743 			goto error;
744 		}
745 		dentry->d_op = &v9fs_cached_dentry_operations;
746 		d_instantiate(dentry, inode);
747 		err = v9fs_fid_add(dentry, fid);
748 		if (err < 0)
749 			goto error;
750 		/* The fid would get clunked via a dput */
751 		fid = NULL;
752 	} else {
753 		/*
754 		 * Not in cached mode. No need to populate
755 		 * inode with stat. We need to get an inode
756 		 * so that we can set the acl with dentry
757 		 */
758 		inode = v9fs_get_inode(dir->i_sb, mode);
759 		if (IS_ERR(inode)) {
760 			err = PTR_ERR(inode);
761 			goto error;
762 		}
763 		dentry->d_op = &v9fs_dentry_operations;
764 		d_instantiate(dentry, inode);
765 	}
766 	/* Now set the ACL based on the default value */
767 	v9fs_set_create_acl(dentry, dacl, pacl);
768 
769 	/* if we are opening a file, assign the open fid to the file */
770 	if (nd && nd->flags & LOOKUP_OPEN) {
771 		filp = lookup_instantiate_filp(nd, dentry, generic_file_open);
772 		if (IS_ERR(filp)) {
773 			p9_client_clunk(ofid);
774 			return PTR_ERR(filp);
775 		}
776 		filp->private_data = ofid;
777 	} else
778 		p9_client_clunk(ofid);
779 
780 	return 0;
781 
782 error:
783 	if (ofid)
784 		p9_client_clunk(ofid);
785 	if (fid)
786 		p9_client_clunk(fid);
787 	return err;
788 }
789 
790 /**
791  * v9fs_vfs_create - VFS hook to create files
792  * @dir: directory inode that is being created
793  * @dentry:  dentry that is being deleted
794  * @mode: create permissions
795  * @nd: path information
796  *
797  */
798 
799 static int
800 v9fs_vfs_create(struct inode *dir, struct dentry *dentry, int mode,
801 		struct nameidata *nd)
802 {
803 	int err;
804 	u32 perm;
805 	int flags;
806 	struct v9fs_session_info *v9ses;
807 	struct p9_fid *fid;
808 	struct file *filp;
809 
810 	err = 0;
811 	fid = NULL;
812 	v9ses = v9fs_inode2v9ses(dir);
813 	perm = unixmode2p9mode(v9ses, mode);
814 	if (nd && nd->flags & LOOKUP_OPEN)
815 		flags = nd->intent.open.flags - 1;
816 	else
817 		flags = O_RDWR;
818 
819 	fid = v9fs_create(v9ses, dir, dentry, NULL, perm,
820 				v9fs_uflags2omode(flags,
821 						v9fs_proto_dotu(v9ses)));
822 	if (IS_ERR(fid)) {
823 		err = PTR_ERR(fid);
824 		fid = NULL;
825 		goto error;
826 	}
827 
828 	/* if we are opening a file, assign the open fid to the file */
829 	if (nd && nd->flags & LOOKUP_OPEN) {
830 		filp = lookup_instantiate_filp(nd, dentry, generic_file_open);
831 		if (IS_ERR(filp)) {
832 			err = PTR_ERR(filp);
833 			goto error;
834 		}
835 
836 		filp->private_data = fid;
837 	} else
838 		p9_client_clunk(fid);
839 
840 	return 0;
841 
842 error:
843 	if (fid)
844 		p9_client_clunk(fid);
845 
846 	return err;
847 }
848 
849 /**
850  * v9fs_vfs_mkdir - VFS mkdir hook to create a directory
851  * @dir:  inode that is being unlinked
852  * @dentry: dentry that is being unlinked
853  * @mode: mode for new directory
854  *
855  */
856 
857 static int v9fs_vfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
858 {
859 	int err;
860 	u32 perm;
861 	struct v9fs_session_info *v9ses;
862 	struct p9_fid *fid;
863 
864 	P9_DPRINTK(P9_DEBUG_VFS, "name %s\n", dentry->d_name.name);
865 	err = 0;
866 	v9ses = v9fs_inode2v9ses(dir);
867 	perm = unixmode2p9mode(v9ses, mode | S_IFDIR);
868 	fid = v9fs_create(v9ses, dir, dentry, NULL, perm, P9_OREAD);
869 	if (IS_ERR(fid)) {
870 		err = PTR_ERR(fid);
871 		fid = NULL;
872 	}
873 
874 	if (fid)
875 		p9_client_clunk(fid);
876 
877 	return err;
878 }
879 
880 
881 /**
882  * v9fs_vfs_mkdir_dotl - VFS mkdir hook to create a directory
883  * @dir:  inode that is being unlinked
884  * @dentry: dentry that is being unlinked
885  * @mode: mode for new directory
886  *
887  */
888 
889 static int v9fs_vfs_mkdir_dotl(struct inode *dir,
890 			       struct dentry *dentry, int omode)
891 {
892 	int err;
893 	struct v9fs_session_info *v9ses;
894 	struct p9_fid *fid = NULL, *dfid = NULL;
895 	gid_t gid;
896 	char *name;
897 	mode_t mode;
898 	struct inode *inode;
899 	struct p9_qid qid;
900 	struct dentry *dir_dentry;
901 	struct posix_acl *dacl = NULL, *pacl = NULL;
902 
903 	P9_DPRINTK(P9_DEBUG_VFS, "name %s\n", dentry->d_name.name);
904 	err = 0;
905 	v9ses = v9fs_inode2v9ses(dir);
906 
907 	omode |= S_IFDIR;
908 	if (dir->i_mode & S_ISGID)
909 		omode |= S_ISGID;
910 
911 	dir_dentry = v9fs_dentry_from_dir_inode(dir);
912 	dfid = v9fs_fid_lookup(dir_dentry);
913 	if (IS_ERR(dfid)) {
914 		err = PTR_ERR(dfid);
915 		P9_DPRINTK(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
916 		dfid = NULL;
917 		goto error;
918 	}
919 
920 	gid = v9fs_get_fsgid_for_create(dir);
921 	mode = omode;
922 	/* Update mode based on ACL value */
923 	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
924 	if (err) {
925 		P9_DPRINTK(P9_DEBUG_VFS,
926 			   "Failed to get acl values in mkdir %d\n", err);
927 		goto error;
928 	}
929 	name = (char *) dentry->d_name.name;
930 	err = p9_client_mkdir_dotl(dfid, name, mode, gid, &qid);
931 	if (err < 0)
932 		goto error;
933 
934 	/* instantiate inode and assign the unopened fid to the dentry */
935 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
936 		fid = p9_client_walk(dfid, 1, &name, 1);
937 		if (IS_ERR(fid)) {
938 			err = PTR_ERR(fid);
939 			P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
940 				err);
941 			fid = NULL;
942 			goto error;
943 		}
944 
945 		inode = v9fs_inode_from_fid(v9ses, fid, dir->i_sb);
946 		if (IS_ERR(inode)) {
947 			err = PTR_ERR(inode);
948 			P9_DPRINTK(P9_DEBUG_VFS, "inode creation failed %d\n",
949 				err);
950 			goto error;
951 		}
952 		dentry->d_op = &v9fs_cached_dentry_operations;
953 		d_instantiate(dentry, inode);
954 		err = v9fs_fid_add(dentry, fid);
955 		if (err < 0)
956 			goto error;
957 		fid = NULL;
958 	} else {
959 		/*
960 		 * Not in cached mode. No need to populate
961 		 * inode with stat. We need to get an inode
962 		 * so that we can set the acl with dentry
963 		 */
964 		inode = v9fs_get_inode(dir->i_sb, mode);
965 		if (IS_ERR(inode)) {
966 			err = PTR_ERR(inode);
967 			goto error;
968 		}
969 		dentry->d_op = &v9fs_dentry_operations;
970 		d_instantiate(dentry, inode);
971 	}
972 	/* Now set the ACL based on the default value */
973 	v9fs_set_create_acl(dentry, dacl, pacl);
974 
975 error:
976 	if (fid)
977 		p9_client_clunk(fid);
978 	return err;
979 }
980 
981 /**
982  * v9fs_vfs_lookup - VFS lookup hook to "walk" to a new inode
983  * @dir:  inode that is being walked from
984  * @dentry: dentry that is being walked to?
985  * @nameidata: path data
986  *
987  */
988 
989 static struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
990 				      struct nameidata *nameidata)
991 {
992 	struct super_block *sb;
993 	struct v9fs_session_info *v9ses;
994 	struct p9_fid *dfid, *fid;
995 	struct inode *inode;
996 	char *name;
997 	int result = 0;
998 
999 	P9_DPRINTK(P9_DEBUG_VFS, "dir: %p dentry: (%s) %p nameidata: %p\n",
1000 		dir, dentry->d_name.name, dentry, nameidata);
1001 
1002 	if (dentry->d_name.len > NAME_MAX)
1003 		return ERR_PTR(-ENAMETOOLONG);
1004 
1005 	sb = dir->i_sb;
1006 	v9ses = v9fs_inode2v9ses(dir);
1007 	/* We can walk d_parent because we hold the dir->i_mutex */
1008 	dfid = v9fs_fid_lookup(dentry->d_parent);
1009 	if (IS_ERR(dfid))
1010 		return ERR_CAST(dfid);
1011 
1012 	name = (char *) dentry->d_name.name;
1013 	fid = p9_client_walk(dfid, 1, &name, 1);
1014 	if (IS_ERR(fid)) {
1015 		result = PTR_ERR(fid);
1016 		if (result == -ENOENT) {
1017 			inode = NULL;
1018 			goto inst_out;
1019 		}
1020 
1021 		return ERR_PTR(result);
1022 	}
1023 
1024 	inode = v9fs_inode_from_fid(v9ses, fid, dir->i_sb);
1025 	if (IS_ERR(inode)) {
1026 		result = PTR_ERR(inode);
1027 		inode = NULL;
1028 		goto error;
1029 	}
1030 
1031 	result = v9fs_fid_add(dentry, fid);
1032 	if (result < 0)
1033 		goto error_iput;
1034 
1035 inst_out:
1036 	if (v9ses->cache)
1037 		dentry->d_op = &v9fs_cached_dentry_operations;
1038 	else
1039 		dentry->d_op = &v9fs_dentry_operations;
1040 
1041 	d_add(dentry, inode);
1042 	return NULL;
1043 
1044 error_iput:
1045 	iput(inode);
1046 error:
1047 	p9_client_clunk(fid);
1048 
1049 	return ERR_PTR(result);
1050 }
1051 
1052 /**
1053  * v9fs_vfs_unlink - VFS unlink hook to delete an inode
1054  * @i:  inode that is being unlinked
1055  * @d: dentry that is being unlinked
1056  *
1057  */
1058 
1059 static int v9fs_vfs_unlink(struct inode *i, struct dentry *d)
1060 {
1061 	return v9fs_remove(i, d, 0);
1062 }
1063 
1064 /**
1065  * v9fs_vfs_rmdir - VFS unlink hook to delete a directory
1066  * @i:  inode that is being unlinked
1067  * @d: dentry that is being unlinked
1068  *
1069  */
1070 
1071 static int v9fs_vfs_rmdir(struct inode *i, struct dentry *d)
1072 {
1073 	return v9fs_remove(i, d, 1);
1074 }
1075 
1076 /**
1077  * v9fs_vfs_rename - VFS hook to rename an inode
1078  * @old_dir:  old dir inode
1079  * @old_dentry: old dentry
1080  * @new_dir: new dir inode
1081  * @new_dentry: new dentry
1082  *
1083  */
1084 
1085 static int
1086 v9fs_vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
1087 		struct inode *new_dir, struct dentry *new_dentry)
1088 {
1089 	struct inode *old_inode;
1090 	struct v9fs_session_info *v9ses;
1091 	struct p9_fid *oldfid;
1092 	struct p9_fid *olddirfid;
1093 	struct p9_fid *newdirfid;
1094 	struct p9_wstat wstat;
1095 	int retval;
1096 
1097 	P9_DPRINTK(P9_DEBUG_VFS, "\n");
1098 	retval = 0;
1099 	old_inode = old_dentry->d_inode;
1100 	v9ses = v9fs_inode2v9ses(old_inode);
1101 	oldfid = v9fs_fid_lookup(old_dentry);
1102 	if (IS_ERR(oldfid))
1103 		return PTR_ERR(oldfid);
1104 
1105 	olddirfid = v9fs_fid_clone(old_dentry->d_parent);
1106 	if (IS_ERR(olddirfid)) {
1107 		retval = PTR_ERR(olddirfid);
1108 		goto done;
1109 	}
1110 
1111 	newdirfid = v9fs_fid_clone(new_dentry->d_parent);
1112 	if (IS_ERR(newdirfid)) {
1113 		retval = PTR_ERR(newdirfid);
1114 		goto clunk_olddir;
1115 	}
1116 
1117 	down_write(&v9ses->rename_sem);
1118 	if (v9fs_proto_dotl(v9ses)) {
1119 		retval = p9_client_rename(oldfid, newdirfid,
1120 					(char *) new_dentry->d_name.name);
1121 		if (retval != -ENOSYS)
1122 			goto clunk_newdir;
1123 	}
1124 	if (old_dentry->d_parent != new_dentry->d_parent) {
1125 		/*
1126 		 * 9P .u can only handle file rename in the same directory
1127 		 */
1128 
1129 		P9_DPRINTK(P9_DEBUG_ERROR,
1130 				"old dir and new dir are different\n");
1131 		retval = -EXDEV;
1132 		goto clunk_newdir;
1133 	}
1134 	v9fs_blank_wstat(&wstat);
1135 	wstat.muid = v9ses->uname;
1136 	wstat.name = (char *) new_dentry->d_name.name;
1137 	retval = p9_client_wstat(oldfid, &wstat);
1138 
1139 clunk_newdir:
1140 	if (!retval)
1141 		/* successful rename */
1142 		d_move(old_dentry, new_dentry);
1143 	up_write(&v9ses->rename_sem);
1144 	p9_client_clunk(newdirfid);
1145 
1146 clunk_olddir:
1147 	p9_client_clunk(olddirfid);
1148 
1149 done:
1150 	return retval;
1151 }
1152 
1153 /**
1154  * v9fs_vfs_getattr - retrieve file metadata
1155  * @mnt: mount information
1156  * @dentry: file to get attributes on
1157  * @stat: metadata structure to populate
1158  *
1159  */
1160 
1161 static int
1162 v9fs_vfs_getattr(struct vfsmount *mnt, struct dentry *dentry,
1163 		 struct kstat *stat)
1164 {
1165 	int err;
1166 	struct v9fs_session_info *v9ses;
1167 	struct p9_fid *fid;
1168 	struct p9_wstat *st;
1169 
1170 	P9_DPRINTK(P9_DEBUG_VFS, "dentry: %p\n", dentry);
1171 	err = -EPERM;
1172 	v9ses = v9fs_inode2v9ses(dentry->d_inode);
1173 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
1174 		return simple_getattr(mnt, dentry, stat);
1175 
1176 	fid = v9fs_fid_lookup(dentry);
1177 	if (IS_ERR(fid))
1178 		return PTR_ERR(fid);
1179 
1180 	st = p9_client_stat(fid);
1181 	if (IS_ERR(st))
1182 		return PTR_ERR(st);
1183 
1184 	v9fs_stat2inode(st, dentry->d_inode, dentry->d_inode->i_sb);
1185 		generic_fillattr(dentry->d_inode, stat);
1186 
1187 	p9stat_free(st);
1188 	kfree(st);
1189 	return 0;
1190 }
1191 
1192 static int
1193 v9fs_vfs_getattr_dotl(struct vfsmount *mnt, struct dentry *dentry,
1194 		 struct kstat *stat)
1195 {
1196 	int err;
1197 	struct v9fs_session_info *v9ses;
1198 	struct p9_fid *fid;
1199 	struct p9_stat_dotl *st;
1200 
1201 	P9_DPRINTK(P9_DEBUG_VFS, "dentry: %p\n", dentry);
1202 	err = -EPERM;
1203 	v9ses = v9fs_inode2v9ses(dentry->d_inode);
1204 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
1205 		return simple_getattr(mnt, dentry, stat);
1206 
1207 	fid = v9fs_fid_lookup(dentry);
1208 	if (IS_ERR(fid))
1209 		return PTR_ERR(fid);
1210 
1211 	/* Ask for all the fields in stat structure. Server will return
1212 	 * whatever it supports
1213 	 */
1214 
1215 	st = p9_client_getattr_dotl(fid, P9_STATS_ALL);
1216 	if (IS_ERR(st))
1217 		return PTR_ERR(st);
1218 
1219 	v9fs_stat2inode_dotl(st, dentry->d_inode);
1220 	generic_fillattr(dentry->d_inode, stat);
1221 	/* Change block size to what the server returned */
1222 	stat->blksize = st->st_blksize;
1223 
1224 	kfree(st);
1225 	return 0;
1226 }
1227 
1228 /**
1229  * v9fs_vfs_setattr - set file metadata
1230  * @dentry: file whose metadata to set
1231  * @iattr: metadata assignment structure
1232  *
1233  */
1234 
1235 static int v9fs_vfs_setattr(struct dentry *dentry, struct iattr *iattr)
1236 {
1237 	int retval;
1238 	struct v9fs_session_info *v9ses;
1239 	struct p9_fid *fid;
1240 	struct p9_wstat wstat;
1241 
1242 	P9_DPRINTK(P9_DEBUG_VFS, "\n");
1243 	retval = -EPERM;
1244 	v9ses = v9fs_inode2v9ses(dentry->d_inode);
1245 	fid = v9fs_fid_lookup(dentry);
1246 	if(IS_ERR(fid))
1247 		return PTR_ERR(fid);
1248 
1249 	v9fs_blank_wstat(&wstat);
1250 	if (iattr->ia_valid & ATTR_MODE)
1251 		wstat.mode = unixmode2p9mode(v9ses, iattr->ia_mode);
1252 
1253 	if (iattr->ia_valid & ATTR_MTIME)
1254 		wstat.mtime = iattr->ia_mtime.tv_sec;
1255 
1256 	if (iattr->ia_valid & ATTR_ATIME)
1257 		wstat.atime = iattr->ia_atime.tv_sec;
1258 
1259 	if (iattr->ia_valid & ATTR_SIZE)
1260 		wstat.length = iattr->ia_size;
1261 
1262 	if (v9fs_proto_dotu(v9ses)) {
1263 		if (iattr->ia_valid & ATTR_UID)
1264 			wstat.n_uid = iattr->ia_uid;
1265 
1266 		if (iattr->ia_valid & ATTR_GID)
1267 			wstat.n_gid = iattr->ia_gid;
1268 	}
1269 
1270 	retval = p9_client_wstat(fid, &wstat);
1271 	if (retval < 0)
1272 		return retval;
1273 
1274 	if ((iattr->ia_valid & ATTR_SIZE) &&
1275 	    iattr->ia_size != i_size_read(dentry->d_inode)) {
1276 		retval = vmtruncate(dentry->d_inode, iattr->ia_size);
1277 		if (retval)
1278 			return retval;
1279 	}
1280 
1281 	setattr_copy(dentry->d_inode, iattr);
1282 	mark_inode_dirty(dentry->d_inode);
1283 	return 0;
1284 }
1285 
1286 /**
1287  * v9fs_vfs_setattr_dotl - set file metadata
1288  * @dentry: file whose metadata to set
1289  * @iattr: metadata assignment structure
1290  *
1291  */
1292 
1293 int v9fs_vfs_setattr_dotl(struct dentry *dentry, struct iattr *iattr)
1294 {
1295 	int retval;
1296 	struct v9fs_session_info *v9ses;
1297 	struct p9_fid *fid;
1298 	struct p9_iattr_dotl p9attr;
1299 
1300 	P9_DPRINTK(P9_DEBUG_VFS, "\n");
1301 
1302 	retval = inode_change_ok(dentry->d_inode, iattr);
1303 	if (retval)
1304 		return retval;
1305 
1306 	p9attr.valid = iattr->ia_valid;
1307 	p9attr.mode = iattr->ia_mode;
1308 	p9attr.uid = iattr->ia_uid;
1309 	p9attr.gid = iattr->ia_gid;
1310 	p9attr.size = iattr->ia_size;
1311 	p9attr.atime_sec = iattr->ia_atime.tv_sec;
1312 	p9attr.atime_nsec = iattr->ia_atime.tv_nsec;
1313 	p9attr.mtime_sec = iattr->ia_mtime.tv_sec;
1314 	p9attr.mtime_nsec = iattr->ia_mtime.tv_nsec;
1315 
1316 	retval = -EPERM;
1317 	v9ses = v9fs_inode2v9ses(dentry->d_inode);
1318 	fid = v9fs_fid_lookup(dentry);
1319 	if (IS_ERR(fid))
1320 		return PTR_ERR(fid);
1321 
1322 	retval = p9_client_setattr(fid, &p9attr);
1323 	if (retval < 0)
1324 		return retval;
1325 
1326 	if ((iattr->ia_valid & ATTR_SIZE) &&
1327 	    iattr->ia_size != i_size_read(dentry->d_inode)) {
1328 		retval = vmtruncate(dentry->d_inode, iattr->ia_size);
1329 		if (retval)
1330 			return retval;
1331 	}
1332 
1333 	setattr_copy(dentry->d_inode, iattr);
1334 	mark_inode_dirty(dentry->d_inode);
1335 	if (iattr->ia_valid & ATTR_MODE) {
1336 		/* We also want to update ACL when we update mode bits */
1337 		retval = v9fs_acl_chmod(dentry);
1338 		if (retval < 0)
1339 			return retval;
1340 	}
1341 	return 0;
1342 }
1343 
1344 /**
1345  * v9fs_stat2inode - populate an inode structure with mistat info
1346  * @stat: Plan 9 metadata (mistat) structure
1347  * @inode: inode to populate
1348  * @sb: superblock of filesystem
1349  *
1350  */
1351 
1352 void
1353 v9fs_stat2inode(struct p9_wstat *stat, struct inode *inode,
1354 	struct super_block *sb)
1355 {
1356 	char ext[32];
1357 	char tag_name[14];
1358 	unsigned int i_nlink;
1359 	struct v9fs_session_info *v9ses = sb->s_fs_info;
1360 
1361 	inode->i_nlink = 1;
1362 
1363 	inode->i_atime.tv_sec = stat->atime;
1364 	inode->i_mtime.tv_sec = stat->mtime;
1365 	inode->i_ctime.tv_sec = stat->mtime;
1366 
1367 	inode->i_uid = v9ses->dfltuid;
1368 	inode->i_gid = v9ses->dfltgid;
1369 
1370 	if (v9fs_proto_dotu(v9ses)) {
1371 		inode->i_uid = stat->n_uid;
1372 		inode->i_gid = stat->n_gid;
1373 	}
1374 	if ((S_ISREG(inode->i_mode)) || (S_ISDIR(inode->i_mode))) {
1375 		if (v9fs_proto_dotu(v9ses) && (stat->extension[0] != '\0')) {
1376 			/*
1377 			 * Hadlink support got added later to
1378 			 * to the .u extension. So there can be
1379 			 * server out there that doesn't support
1380 			 * this even with .u extension. So check
1381 			 * for non NULL stat->extension
1382 			 */
1383 			strncpy(ext, stat->extension, sizeof(ext));
1384 			/* HARDLINKCOUNT %u */
1385 			sscanf(ext, "%13s %u", tag_name, &i_nlink);
1386 			if (!strncmp(tag_name, "HARDLINKCOUNT", 13))
1387 				inode->i_nlink = i_nlink;
1388 		}
1389 	}
1390 	inode->i_mode = p9mode2unixmode(v9ses, stat->mode);
1391 	if ((S_ISBLK(inode->i_mode)) || (S_ISCHR(inode->i_mode))) {
1392 		char type = 0;
1393 		int major = -1;
1394 		int minor = -1;
1395 
1396 		strncpy(ext, stat->extension, sizeof(ext));
1397 		sscanf(ext, "%c %u %u", &type, &major, &minor);
1398 		switch (type) {
1399 		case 'c':
1400 			inode->i_mode &= ~S_IFBLK;
1401 			inode->i_mode |= S_IFCHR;
1402 			break;
1403 		case 'b':
1404 			break;
1405 		default:
1406 			P9_DPRINTK(P9_DEBUG_ERROR,
1407 				"Unknown special type %c %s\n", type,
1408 				stat->extension);
1409 		};
1410 		inode->i_rdev = MKDEV(major, minor);
1411 		init_special_inode(inode, inode->i_mode, inode->i_rdev);
1412 	} else
1413 		inode->i_rdev = 0;
1414 
1415 	i_size_write(inode, stat->length);
1416 
1417 	/* not real number of blocks, but 512 byte ones ... */
1418 	inode->i_blocks = (i_size_read(inode) + 512 - 1) >> 9;
1419 }
1420 
1421 /**
1422  * v9fs_stat2inode_dotl - populate an inode structure with stat info
1423  * @stat: stat structure
1424  * @inode: inode to populate
1425  * @sb: superblock of filesystem
1426  *
1427  */
1428 
1429 void
1430 v9fs_stat2inode_dotl(struct p9_stat_dotl *stat, struct inode *inode)
1431 {
1432 
1433 	if ((stat->st_result_mask & P9_STATS_BASIC) == P9_STATS_BASIC) {
1434 		inode->i_atime.tv_sec = stat->st_atime_sec;
1435 		inode->i_atime.tv_nsec = stat->st_atime_nsec;
1436 		inode->i_mtime.tv_sec = stat->st_mtime_sec;
1437 		inode->i_mtime.tv_nsec = stat->st_mtime_nsec;
1438 		inode->i_ctime.tv_sec = stat->st_ctime_sec;
1439 		inode->i_ctime.tv_nsec = stat->st_ctime_nsec;
1440 		inode->i_uid = stat->st_uid;
1441 		inode->i_gid = stat->st_gid;
1442 		inode->i_nlink = stat->st_nlink;
1443 		inode->i_mode = stat->st_mode;
1444 		inode->i_rdev = new_decode_dev(stat->st_rdev);
1445 
1446 		if ((S_ISBLK(inode->i_mode)) || (S_ISCHR(inode->i_mode)))
1447 			init_special_inode(inode, inode->i_mode, inode->i_rdev);
1448 
1449 		i_size_write(inode, stat->st_size);
1450 		inode->i_blocks = stat->st_blocks;
1451 	} else {
1452 		if (stat->st_result_mask & P9_STATS_ATIME) {
1453 			inode->i_atime.tv_sec = stat->st_atime_sec;
1454 			inode->i_atime.tv_nsec = stat->st_atime_nsec;
1455 		}
1456 		if (stat->st_result_mask & P9_STATS_MTIME) {
1457 			inode->i_mtime.tv_sec = stat->st_mtime_sec;
1458 			inode->i_mtime.tv_nsec = stat->st_mtime_nsec;
1459 		}
1460 		if (stat->st_result_mask & P9_STATS_CTIME) {
1461 			inode->i_ctime.tv_sec = stat->st_ctime_sec;
1462 			inode->i_ctime.tv_nsec = stat->st_ctime_nsec;
1463 		}
1464 		if (stat->st_result_mask & P9_STATS_UID)
1465 			inode->i_uid = stat->st_uid;
1466 		if (stat->st_result_mask & P9_STATS_GID)
1467 			inode->i_gid = stat->st_gid;
1468 		if (stat->st_result_mask & P9_STATS_NLINK)
1469 			inode->i_nlink = stat->st_nlink;
1470 		if (stat->st_result_mask & P9_STATS_MODE) {
1471 			inode->i_mode = stat->st_mode;
1472 			if ((S_ISBLK(inode->i_mode)) ||
1473 						(S_ISCHR(inode->i_mode)))
1474 				init_special_inode(inode, inode->i_mode,
1475 								inode->i_rdev);
1476 		}
1477 		if (stat->st_result_mask & P9_STATS_RDEV)
1478 			inode->i_rdev = new_decode_dev(stat->st_rdev);
1479 		if (stat->st_result_mask & P9_STATS_SIZE)
1480 			i_size_write(inode, stat->st_size);
1481 		if (stat->st_result_mask & P9_STATS_BLOCKS)
1482 			inode->i_blocks = stat->st_blocks;
1483 	}
1484 	if (stat->st_result_mask & P9_STATS_GEN)
1485 			inode->i_generation = stat->st_gen;
1486 
1487 	/* Currently we don't support P9_STATS_BTIME and P9_STATS_DATA_VERSION
1488 	 * because the inode structure does not have fields for them.
1489 	 */
1490 }
1491 
1492 /**
1493  * v9fs_qid2ino - convert qid into inode number
1494  * @qid: qid to hash
1495  *
1496  * BUG: potential for inode number collisions?
1497  */
1498 
1499 ino_t v9fs_qid2ino(struct p9_qid *qid)
1500 {
1501 	u64 path = qid->path + 2;
1502 	ino_t i = 0;
1503 
1504 	if (sizeof(ino_t) == sizeof(path))
1505 		memcpy(&i, &path, sizeof(ino_t));
1506 	else
1507 		i = (ino_t) (path ^ (path >> 32));
1508 
1509 	return i;
1510 }
1511 
1512 /**
1513  * v9fs_readlink - read a symlink's location (internal version)
1514  * @dentry: dentry for symlink
1515  * @buffer: buffer to load symlink location into
1516  * @buflen: length of buffer
1517  *
1518  */
1519 
1520 static int v9fs_readlink(struct dentry *dentry, char *buffer, int buflen)
1521 {
1522 	int retval;
1523 
1524 	struct v9fs_session_info *v9ses;
1525 	struct p9_fid *fid;
1526 	struct p9_wstat *st;
1527 
1528 	P9_DPRINTK(P9_DEBUG_VFS, " %s\n", dentry->d_name.name);
1529 	retval = -EPERM;
1530 	v9ses = v9fs_inode2v9ses(dentry->d_inode);
1531 	fid = v9fs_fid_lookup(dentry);
1532 	if (IS_ERR(fid))
1533 		return PTR_ERR(fid);
1534 
1535 	if (!v9fs_proto_dotu(v9ses))
1536 		return -EBADF;
1537 
1538 	st = p9_client_stat(fid);
1539 	if (IS_ERR(st))
1540 		return PTR_ERR(st);
1541 
1542 	if (!(st->mode & P9_DMSYMLINK)) {
1543 		retval = -EINVAL;
1544 		goto done;
1545 	}
1546 
1547 	/* copy extension buffer into buffer */
1548 	strncpy(buffer, st->extension, buflen);
1549 
1550 	P9_DPRINTK(P9_DEBUG_VFS,
1551 		"%s -> %s (%s)\n", dentry->d_name.name, st->extension, buffer);
1552 
1553 	retval = strnlen(buffer, buflen);
1554 done:
1555 	p9stat_free(st);
1556 	kfree(st);
1557 	return retval;
1558 }
1559 
1560 /**
1561  * v9fs_vfs_follow_link - follow a symlink path
1562  * @dentry: dentry for symlink
1563  * @nd: nameidata
1564  *
1565  */
1566 
1567 static void *v9fs_vfs_follow_link(struct dentry *dentry, struct nameidata *nd)
1568 {
1569 	int len = 0;
1570 	char *link = __getname();
1571 
1572 	P9_DPRINTK(P9_DEBUG_VFS, "%s n", dentry->d_name.name);
1573 
1574 	if (!link)
1575 		link = ERR_PTR(-ENOMEM);
1576 	else {
1577 		len = v9fs_readlink(dentry, link, PATH_MAX);
1578 
1579 		if (len < 0) {
1580 			__putname(link);
1581 			link = ERR_PTR(len);
1582 		} else
1583 			link[min(len, PATH_MAX-1)] = 0;
1584 	}
1585 	nd_set_link(nd, link);
1586 
1587 	return NULL;
1588 }
1589 
1590 /**
1591  * v9fs_vfs_put_link - release a symlink path
1592  * @dentry: dentry for symlink
1593  * @nd: nameidata
1594  * @p: unused
1595  *
1596  */
1597 
1598 static void
1599 v9fs_vfs_put_link(struct dentry *dentry, struct nameidata *nd, void *p)
1600 {
1601 	char *s = nd_get_link(nd);
1602 
1603 	P9_DPRINTK(P9_DEBUG_VFS, " %s %s\n", dentry->d_name.name,
1604 		IS_ERR(s) ? "<error>" : s);
1605 	if (!IS_ERR(s))
1606 		__putname(s);
1607 }
1608 
1609 /**
1610  * v9fs_vfs_mkspecial - create a special file
1611  * @dir: inode to create special file in
1612  * @dentry: dentry to create
1613  * @mode: mode to create special file
1614  * @extension: 9p2000.u format extension string representing special file
1615  *
1616  */
1617 
1618 static int v9fs_vfs_mkspecial(struct inode *dir, struct dentry *dentry,
1619 	int mode, const char *extension)
1620 {
1621 	u32 perm;
1622 	struct v9fs_session_info *v9ses;
1623 	struct p9_fid *fid;
1624 
1625 	v9ses = v9fs_inode2v9ses(dir);
1626 	if (!v9fs_proto_dotu(v9ses)) {
1627 		P9_DPRINTK(P9_DEBUG_ERROR, "not extended\n");
1628 		return -EPERM;
1629 	}
1630 
1631 	perm = unixmode2p9mode(v9ses, mode);
1632 	fid = v9fs_create(v9ses, dir, dentry, (char *) extension, perm,
1633 								P9_OREAD);
1634 	if (IS_ERR(fid))
1635 		return PTR_ERR(fid);
1636 
1637 	p9_client_clunk(fid);
1638 	return 0;
1639 }
1640 
1641 /**
1642  * v9fs_vfs_symlink_dotl - helper function to create symlinks
1643  * @dir: directory inode containing symlink
1644  * @dentry: dentry for symlink
1645  * @symname: symlink data
1646  *
1647  * See Also: 9P2000.L RFC for more information
1648  *
1649  */
1650 
1651 static int
1652 v9fs_vfs_symlink_dotl(struct inode *dir, struct dentry *dentry,
1653 		const char *symname)
1654 {
1655 	struct v9fs_session_info *v9ses;
1656 	struct p9_fid *dfid;
1657 	struct p9_fid *fid = NULL;
1658 	struct inode *inode;
1659 	struct p9_qid qid;
1660 	char *name;
1661 	int err;
1662 	gid_t gid;
1663 
1664 	name = (char *) dentry->d_name.name;
1665 	P9_DPRINTK(P9_DEBUG_VFS, "v9fs_vfs_symlink_dotl : %lu,%s,%s\n",
1666 			dir->i_ino, name, symname);
1667 	v9ses = v9fs_inode2v9ses(dir);
1668 
1669 	dfid = v9fs_fid_lookup(dentry->d_parent);
1670 	if (IS_ERR(dfid)) {
1671 		err = PTR_ERR(dfid);
1672 		P9_DPRINTK(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
1673 		return err;
1674 	}
1675 
1676 	gid = v9fs_get_fsgid_for_create(dir);
1677 
1678 	/* Server doesn't alter fid on TSYMLINK. Hence no need to clone it. */
1679 	err = p9_client_symlink(dfid, name, (char *)symname, gid, &qid);
1680 
1681 	if (err < 0) {
1682 		P9_DPRINTK(P9_DEBUG_VFS, "p9_client_symlink failed %d\n", err);
1683 		goto error;
1684 	}
1685 
1686 	if (v9ses->cache) {
1687 		/* Now walk from the parent so we can get an unopened fid. */
1688 		fid = p9_client_walk(dfid, 1, &name, 1);
1689 		if (IS_ERR(fid)) {
1690 			err = PTR_ERR(fid);
1691 			P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
1692 					err);
1693 			fid = NULL;
1694 			goto error;
1695 		}
1696 
1697 		/* instantiate inode and assign the unopened fid to dentry */
1698 		inode = v9fs_inode_from_fid(v9ses, fid, dir->i_sb);
1699 		if (IS_ERR(inode)) {
1700 			err = PTR_ERR(inode);
1701 			P9_DPRINTK(P9_DEBUG_VFS, "inode creation failed %d\n",
1702 					err);
1703 			goto error;
1704 		}
1705 		dentry->d_op = &v9fs_cached_dentry_operations;
1706 		d_instantiate(dentry, inode);
1707 		err = v9fs_fid_add(dentry, fid);
1708 		if (err < 0)
1709 			goto error;
1710 		fid = NULL;
1711 	} else {
1712 		/* Not in cached mode. No need to populate inode with stat */
1713 		inode = v9fs_get_inode(dir->i_sb, S_IFLNK);
1714 		if (IS_ERR(inode)) {
1715 			err = PTR_ERR(inode);
1716 			goto error;
1717 		}
1718 		dentry->d_op = &v9fs_dentry_operations;
1719 		d_instantiate(dentry, inode);
1720 	}
1721 
1722 error:
1723 	if (fid)
1724 		p9_client_clunk(fid);
1725 
1726 	return err;
1727 }
1728 
1729 /**
1730  * v9fs_vfs_symlink - helper function to create symlinks
1731  * @dir: directory inode containing symlink
1732  * @dentry: dentry for symlink
1733  * @symname: symlink data
1734  *
1735  * See Also: 9P2000.u RFC for more information
1736  *
1737  */
1738 
1739 static int
1740 v9fs_vfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname)
1741 {
1742 	P9_DPRINTK(P9_DEBUG_VFS, " %lu,%s,%s\n", dir->i_ino,
1743 					dentry->d_name.name, symname);
1744 
1745 	return v9fs_vfs_mkspecial(dir, dentry, S_IFLNK, symname);
1746 }
1747 
1748 /**
1749  * v9fs_vfs_link - create a hardlink
1750  * @old_dentry: dentry for file to link to
1751  * @dir: inode destination for new link
1752  * @dentry: dentry for link
1753  *
1754  */
1755 
1756 static int
1757 v9fs_vfs_link(struct dentry *old_dentry, struct inode *dir,
1758 	      struct dentry *dentry)
1759 {
1760 	int retval;
1761 	struct p9_fid *oldfid;
1762 	char *name;
1763 
1764 	P9_DPRINTK(P9_DEBUG_VFS,
1765 		" %lu,%s,%s\n", dir->i_ino, dentry->d_name.name,
1766 		old_dentry->d_name.name);
1767 
1768 	oldfid = v9fs_fid_clone(old_dentry);
1769 	if (IS_ERR(oldfid))
1770 		return PTR_ERR(oldfid);
1771 
1772 	name = __getname();
1773 	if (unlikely(!name)) {
1774 		retval = -ENOMEM;
1775 		goto clunk_fid;
1776 	}
1777 
1778 	sprintf(name, "%d\n", oldfid->fid);
1779 	retval = v9fs_vfs_mkspecial(dir, dentry, P9_DMLINK, name);
1780 	__putname(name);
1781 
1782 clunk_fid:
1783 	p9_client_clunk(oldfid);
1784 	return retval;
1785 }
1786 
1787 /**
1788  * v9fs_vfs_link_dotl - create a hardlink for dotl
1789  * @old_dentry: dentry for file to link to
1790  * @dir: inode destination for new link
1791  * @dentry: dentry for link
1792  *
1793  */
1794 
1795 static int
1796 v9fs_vfs_link_dotl(struct dentry *old_dentry, struct inode *dir,
1797 		struct dentry *dentry)
1798 {
1799 	int err;
1800 	struct p9_fid *dfid, *oldfid;
1801 	char *name;
1802 	struct v9fs_session_info *v9ses;
1803 	struct dentry *dir_dentry;
1804 
1805 	P9_DPRINTK(P9_DEBUG_VFS, "dir ino: %lu, old_name: %s, new_name: %s\n",
1806 			dir->i_ino, old_dentry->d_name.name,
1807 			dentry->d_name.name);
1808 
1809 	v9ses = v9fs_inode2v9ses(dir);
1810 	dir_dentry = v9fs_dentry_from_dir_inode(dir);
1811 	dfid = v9fs_fid_lookup(dir_dentry);
1812 	if (IS_ERR(dfid))
1813 		return PTR_ERR(dfid);
1814 
1815 	oldfid = v9fs_fid_lookup(old_dentry);
1816 	if (IS_ERR(oldfid))
1817 		return PTR_ERR(oldfid);
1818 
1819 	name = (char *) dentry->d_name.name;
1820 
1821 	err = p9_client_link(dfid, oldfid, (char *)dentry->d_name.name);
1822 
1823 	if (err < 0) {
1824 		P9_DPRINTK(P9_DEBUG_VFS, "p9_client_link failed %d\n", err);
1825 		return err;
1826 	}
1827 
1828 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
1829 		/* Get the latest stat info from server. */
1830 		struct p9_fid *fid;
1831 		struct p9_stat_dotl *st;
1832 
1833 		fid = v9fs_fid_lookup(old_dentry);
1834 		if (IS_ERR(fid))
1835 			return PTR_ERR(fid);
1836 
1837 		st = p9_client_getattr_dotl(fid, P9_STATS_BASIC);
1838 		if (IS_ERR(st))
1839 			return PTR_ERR(st);
1840 
1841 		v9fs_stat2inode_dotl(st, old_dentry->d_inode);
1842 
1843 		kfree(st);
1844 	} else {
1845 		/* Caching disabled. No need to get upto date stat info.
1846 		 * This dentry will be released immediately. So, just hold the
1847 		 * inode
1848 		 */
1849 		ihold(old_dentry->d_inode);
1850 	}
1851 
1852 	dentry->d_op = old_dentry->d_op;
1853 	d_instantiate(dentry, old_dentry->d_inode);
1854 
1855 	return err;
1856 }
1857 
1858 /**
1859  * v9fs_vfs_mknod - create a special file
1860  * @dir: inode destination for new link
1861  * @dentry: dentry for file
1862  * @mode: mode for creation
1863  * @rdev: device associated with special file
1864  *
1865  */
1866 
1867 static int
1868 v9fs_vfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t rdev)
1869 {
1870 	int retval;
1871 	char *name;
1872 
1873 	P9_DPRINTK(P9_DEBUG_VFS,
1874 		" %lu,%s mode: %x MAJOR: %u MINOR: %u\n", dir->i_ino,
1875 		dentry->d_name.name, mode, MAJOR(rdev), MINOR(rdev));
1876 
1877 	if (!new_valid_dev(rdev))
1878 		return -EINVAL;
1879 
1880 	name = __getname();
1881 	if (!name)
1882 		return -ENOMEM;
1883 	/* build extension */
1884 	if (S_ISBLK(mode))
1885 		sprintf(name, "b %u %u", MAJOR(rdev), MINOR(rdev));
1886 	else if (S_ISCHR(mode))
1887 		sprintf(name, "c %u %u", MAJOR(rdev), MINOR(rdev));
1888 	else if (S_ISFIFO(mode))
1889 		*name = 0;
1890 	else if (S_ISSOCK(mode))
1891 		*name = 0;
1892 	else {
1893 		__putname(name);
1894 		return -EINVAL;
1895 	}
1896 
1897 	retval = v9fs_vfs_mkspecial(dir, dentry, mode, name);
1898 	__putname(name);
1899 
1900 	return retval;
1901 }
1902 
1903 /**
1904  * v9fs_vfs_mknod_dotl - create a special file
1905  * @dir: inode destination for new link
1906  * @dentry: dentry for file
1907  * @mode: mode for creation
1908  * @rdev: device associated with special file
1909  *
1910  */
1911 static int
1912 v9fs_vfs_mknod_dotl(struct inode *dir, struct dentry *dentry, int omode,
1913 		dev_t rdev)
1914 {
1915 	int err;
1916 	char *name;
1917 	mode_t mode;
1918 	struct v9fs_session_info *v9ses;
1919 	struct p9_fid *fid = NULL, *dfid = NULL;
1920 	struct inode *inode;
1921 	gid_t gid;
1922 	struct p9_qid qid;
1923 	struct dentry *dir_dentry;
1924 	struct posix_acl *dacl = NULL, *pacl = NULL;
1925 
1926 	P9_DPRINTK(P9_DEBUG_VFS,
1927 		" %lu,%s mode: %x MAJOR: %u MINOR: %u\n", dir->i_ino,
1928 		dentry->d_name.name, omode, MAJOR(rdev), MINOR(rdev));
1929 
1930 	if (!new_valid_dev(rdev))
1931 		return -EINVAL;
1932 
1933 	v9ses = v9fs_inode2v9ses(dir);
1934 	dir_dentry = v9fs_dentry_from_dir_inode(dir);
1935 	dfid = v9fs_fid_lookup(dir_dentry);
1936 	if (IS_ERR(dfid)) {
1937 		err = PTR_ERR(dfid);
1938 		P9_DPRINTK(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
1939 		dfid = NULL;
1940 		goto error;
1941 	}
1942 
1943 	gid = v9fs_get_fsgid_for_create(dir);
1944 	mode = omode;
1945 	/* Update mode based on ACL value */
1946 	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
1947 	if (err) {
1948 		P9_DPRINTK(P9_DEBUG_VFS,
1949 			   "Failed to get acl values in mknod %d\n", err);
1950 		goto error;
1951 	}
1952 	name = (char *) dentry->d_name.name;
1953 
1954 	err = p9_client_mknod_dotl(dfid, name, mode, rdev, gid, &qid);
1955 	if (err < 0)
1956 		goto error;
1957 
1958 	/* instantiate inode and assign the unopened fid to the dentry */
1959 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
1960 		fid = p9_client_walk(dfid, 1, &name, 1);
1961 		if (IS_ERR(fid)) {
1962 			err = PTR_ERR(fid);
1963 			P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
1964 				err);
1965 			fid = NULL;
1966 			goto error;
1967 		}
1968 
1969 		inode = v9fs_inode_from_fid(v9ses, fid, dir->i_sb);
1970 		if (IS_ERR(inode)) {
1971 			err = PTR_ERR(inode);
1972 			P9_DPRINTK(P9_DEBUG_VFS, "inode creation failed %d\n",
1973 				err);
1974 			goto error;
1975 		}
1976 		dentry->d_op = &v9fs_cached_dentry_operations;
1977 		d_instantiate(dentry, inode);
1978 		err = v9fs_fid_add(dentry, fid);
1979 		if (err < 0)
1980 			goto error;
1981 		fid = NULL;
1982 	} else {
1983 		/*
1984 		 * Not in cached mode. No need to populate inode with stat.
1985 		 * socket syscall returns a fd, so we need instantiate
1986 		 */
1987 		inode = v9fs_get_inode(dir->i_sb, mode);
1988 		if (IS_ERR(inode)) {
1989 			err = PTR_ERR(inode);
1990 			goto error;
1991 		}
1992 		dentry->d_op = &v9fs_dentry_operations;
1993 		d_instantiate(dentry, inode);
1994 	}
1995 	/* Now set the ACL based on the default value */
1996 	v9fs_set_create_acl(dentry, dacl, pacl);
1997 error:
1998 	if (fid)
1999 		p9_client_clunk(fid);
2000 	return err;
2001 }
2002 
2003 static int
2004 v9fs_vfs_readlink_dotl(struct dentry *dentry, char *buffer, int buflen)
2005 {
2006 	int retval;
2007 	struct p9_fid *fid;
2008 	char *target = NULL;
2009 
2010 	P9_DPRINTK(P9_DEBUG_VFS, " %s\n", dentry->d_name.name);
2011 	retval = -EPERM;
2012 	fid = v9fs_fid_lookup(dentry);
2013 	if (IS_ERR(fid))
2014 		return PTR_ERR(fid);
2015 
2016 	retval = p9_client_readlink(fid, &target);
2017 	if (retval < 0)
2018 		return retval;
2019 
2020 	strncpy(buffer, target, buflen);
2021 	P9_DPRINTK(P9_DEBUG_VFS, "%s -> %s\n", dentry->d_name.name, buffer);
2022 
2023 	retval = strnlen(buffer, buflen);
2024 	return retval;
2025 }
2026 
2027 /**
2028  * v9fs_vfs_follow_link_dotl - follow a symlink path
2029  * @dentry: dentry for symlink
2030  * @nd: nameidata
2031  *
2032  */
2033 
2034 static void *
2035 v9fs_vfs_follow_link_dotl(struct dentry *dentry, struct nameidata *nd)
2036 {
2037 	int len = 0;
2038 	char *link = __getname();
2039 
2040 	P9_DPRINTK(P9_DEBUG_VFS, "%s n", dentry->d_name.name);
2041 
2042 	if (!link)
2043 		link = ERR_PTR(-ENOMEM);
2044 	else {
2045 		len = v9fs_vfs_readlink_dotl(dentry, link, PATH_MAX);
2046 		if (len < 0) {
2047 			__putname(link);
2048 			link = ERR_PTR(len);
2049 		} else
2050 			link[min(len, PATH_MAX-1)] = 0;
2051 	}
2052 	nd_set_link(nd, link);
2053 
2054 	return NULL;
2055 }
2056 
2057 static const struct inode_operations v9fs_dir_inode_operations_dotu = {
2058 	.create = v9fs_vfs_create,
2059 	.lookup = v9fs_vfs_lookup,
2060 	.symlink = v9fs_vfs_symlink,
2061 	.link = v9fs_vfs_link,
2062 	.unlink = v9fs_vfs_unlink,
2063 	.mkdir = v9fs_vfs_mkdir,
2064 	.rmdir = v9fs_vfs_rmdir,
2065 	.mknod = v9fs_vfs_mknod,
2066 	.rename = v9fs_vfs_rename,
2067 	.getattr = v9fs_vfs_getattr,
2068 	.setattr = v9fs_vfs_setattr,
2069 };
2070 
2071 static const struct inode_operations v9fs_dir_inode_operations_dotl = {
2072 	.create = v9fs_vfs_create_dotl,
2073 	.lookup = v9fs_vfs_lookup,
2074 	.link = v9fs_vfs_link_dotl,
2075 	.symlink = v9fs_vfs_symlink_dotl,
2076 	.unlink = v9fs_vfs_unlink,
2077 	.mkdir = v9fs_vfs_mkdir_dotl,
2078 	.rmdir = v9fs_vfs_rmdir,
2079 	.mknod = v9fs_vfs_mknod_dotl,
2080 	.rename = v9fs_vfs_rename,
2081 	.getattr = v9fs_vfs_getattr_dotl,
2082 	.setattr = v9fs_vfs_setattr_dotl,
2083 	.setxattr = generic_setxattr,
2084 	.getxattr = generic_getxattr,
2085 	.removexattr = generic_removexattr,
2086 	.listxattr = v9fs_listxattr,
2087 	.check_acl = v9fs_check_acl,
2088 };
2089 
2090 static const struct inode_operations v9fs_dir_inode_operations = {
2091 	.create = v9fs_vfs_create,
2092 	.lookup = v9fs_vfs_lookup,
2093 	.unlink = v9fs_vfs_unlink,
2094 	.mkdir = v9fs_vfs_mkdir,
2095 	.rmdir = v9fs_vfs_rmdir,
2096 	.mknod = v9fs_vfs_mknod,
2097 	.rename = v9fs_vfs_rename,
2098 	.getattr = v9fs_vfs_getattr,
2099 	.setattr = v9fs_vfs_setattr,
2100 };
2101 
2102 static const struct inode_operations v9fs_file_inode_operations = {
2103 	.getattr = v9fs_vfs_getattr,
2104 	.setattr = v9fs_vfs_setattr,
2105 };
2106 
2107 static const struct inode_operations v9fs_file_inode_operations_dotl = {
2108 	.getattr = v9fs_vfs_getattr_dotl,
2109 	.setattr = v9fs_vfs_setattr_dotl,
2110 	.setxattr = generic_setxattr,
2111 	.getxattr = generic_getxattr,
2112 	.removexattr = generic_removexattr,
2113 	.listxattr = v9fs_listxattr,
2114 	.check_acl = v9fs_check_acl,
2115 };
2116 
2117 static const struct inode_operations v9fs_symlink_inode_operations = {
2118 	.readlink = generic_readlink,
2119 	.follow_link = v9fs_vfs_follow_link,
2120 	.put_link = v9fs_vfs_put_link,
2121 	.getattr = v9fs_vfs_getattr,
2122 	.setattr = v9fs_vfs_setattr,
2123 };
2124 
2125 static const struct inode_operations v9fs_symlink_inode_operations_dotl = {
2126 	.readlink = v9fs_vfs_readlink_dotl,
2127 	.follow_link = v9fs_vfs_follow_link_dotl,
2128 	.put_link = v9fs_vfs_put_link,
2129 	.getattr = v9fs_vfs_getattr_dotl,
2130 	.setattr = v9fs_vfs_setattr_dotl,
2131 	.setxattr = generic_setxattr,
2132 	.getxattr = generic_getxattr,
2133 	.removexattr = generic_removexattr,
2134 	.listxattr = v9fs_listxattr,
2135 };
2136