xref: /openbmc/linux/fs/9p/vfs_inode_dotl.c (revision df2634f43f5106947f3735a0b61a6527a4b278cd)
1 /*
2  *  linux/fs/9p/vfs_inode_dotl.c
3  *
4  * This file contains vfs inode ops for the 9P2000.L protocol.
5  *
6  *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
7  *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
8  *
9  *  This program is free software; you can redistribute it and/or modify
10  *  it under the terms of the GNU General Public License version 2
11  *  as published by the Free Software Foundation.
12  *
13  *  This program is distributed in the hope that it will be useful,
14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  *  GNU General Public License for more details.
17  *
18  *  You should have received a copy of the GNU General Public License
19  *  along with this program; if not, write to:
20  *  Free Software Foundation
21  *  51 Franklin Street, Fifth Floor
22  *  Boston, MA  02111-1301  USA
23  *
24  */
25 
26 #include <linux/module.h>
27 #include <linux/errno.h>
28 #include <linux/fs.h>
29 #include <linux/file.h>
30 #include <linux/pagemap.h>
31 #include <linux/stat.h>
32 #include <linux/string.h>
33 #include <linux/inet.h>
34 #include <linux/namei.h>
35 #include <linux/idr.h>
36 #include <linux/sched.h>
37 #include <linux/slab.h>
38 #include <linux/xattr.h>
39 #include <linux/posix_acl.h>
40 #include <net/9p/9p.h>
41 #include <net/9p/client.h>
42 
43 #include "v9fs.h"
44 #include "v9fs_vfs.h"
45 #include "fid.h"
46 #include "cache.h"
47 #include "xattr.h"
48 #include "acl.h"
49 
50 static int
51 v9fs_vfs_mknod_dotl(struct inode *dir, struct dentry *dentry, int omode,
52 		    dev_t rdev);
53 
54 /**
55  * v9fs_get_fsgid_for_create - Helper function to get the gid for creating a
56  * new file system object. This checks the S_ISGID to determine the owning
57  * group of the new file system object.
58  */
59 
60 static gid_t v9fs_get_fsgid_for_create(struct inode *dir_inode)
61 {
62 	BUG_ON(dir_inode == NULL);
63 
64 	if (dir_inode->i_mode & S_ISGID) {
65 		/* set_gid bit is set.*/
66 		return dir_inode->i_gid;
67 	}
68 	return current_fsgid();
69 }
70 
71 /**
72  * v9fs_dentry_from_dir_inode - helper function to get the dentry from
73  * dir inode.
74  *
75  */
76 
77 static struct dentry *v9fs_dentry_from_dir_inode(struct inode *inode)
78 {
79 	struct dentry *dentry;
80 
81 	spin_lock(&inode->i_lock);
82 	/* Directory should have only one entry. */
83 	BUG_ON(S_ISDIR(inode->i_mode) && !list_is_singular(&inode->i_dentry));
84 	dentry = list_entry(inode->i_dentry.next, struct dentry, d_alias);
85 	spin_unlock(&inode->i_lock);
86 	return dentry;
87 }
88 
89 struct inode *
90 v9fs_inode_dotl(struct v9fs_session_info *v9ses, struct p9_fid *fid,
91 	struct super_block *sb)
92 {
93 	struct inode *ret = NULL;
94 	int err;
95 	struct p9_stat_dotl *st;
96 
97 	st = p9_client_getattr_dotl(fid, P9_STATS_BASIC);
98 	if (IS_ERR(st))
99 		return ERR_CAST(st);
100 
101 	ret = v9fs_get_inode(sb, st->st_mode);
102 	if (IS_ERR(ret)) {
103 		err = PTR_ERR(ret);
104 		goto error;
105 	}
106 
107 	v9fs_stat2inode_dotl(st, ret);
108 	ret->i_ino = v9fs_qid2ino(&st->qid);
109 #ifdef CONFIG_9P_FSCACHE
110 	v9fs_vcookie_set_qid(ret, &st->qid);
111 	v9fs_cache_inode_get_cookie(ret);
112 #endif
113 	err = v9fs_get_acl(ret, fid);
114 	if (err) {
115 		iput(ret);
116 		goto error;
117 	}
118 	kfree(st);
119 	return ret;
120 error:
121 	kfree(st);
122 	return ERR_PTR(err);
123 }
124 
125 /**
126  * v9fs_vfs_create_dotl - VFS hook to create files for 9P2000.L protocol.
127  * @dir: directory inode that is being created
128  * @dentry:  dentry that is being deleted
129  * @mode: create permissions
130  * @nd: path information
131  *
132  */
133 
134 static int
135 v9fs_vfs_create_dotl(struct inode *dir, struct dentry *dentry, int omode,
136 		struct nameidata *nd)
137 {
138 	int err = 0;
139 	char *name = NULL;
140 	gid_t gid;
141 	int flags;
142 	mode_t mode;
143 	struct v9fs_session_info *v9ses;
144 	struct p9_fid *fid = NULL;
145 	struct p9_fid *dfid, *ofid;
146 	struct file *filp;
147 	struct p9_qid qid;
148 	struct inode *inode;
149 	struct posix_acl *pacl = NULL, *dacl = NULL;
150 
151 	v9ses = v9fs_inode2v9ses(dir);
152 	if (nd && nd->flags & LOOKUP_OPEN)
153 		flags = nd->intent.open.flags - 1;
154 	else {
155 		/*
156 		 * create call without LOOKUP_OPEN is due
157 		 * to mknod of regular files. So use mknod
158 		 * operation.
159 		 */
160 		return v9fs_vfs_mknod_dotl(dir, dentry, omode, 0);
161 	}
162 
163 	name = (char *) dentry->d_name.name;
164 	P9_DPRINTK(P9_DEBUG_VFS, "v9fs_vfs_create_dotl: name:%s flags:0x%x "
165 			"mode:0x%x\n", name, flags, omode);
166 
167 	dfid = v9fs_fid_lookup(dentry->d_parent);
168 	if (IS_ERR(dfid)) {
169 		err = PTR_ERR(dfid);
170 		P9_DPRINTK(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
171 		return err;
172 	}
173 
174 	/* clone a fid to use for creation */
175 	ofid = p9_client_walk(dfid, 0, NULL, 1);
176 	if (IS_ERR(ofid)) {
177 		err = PTR_ERR(ofid);
178 		P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
179 		return err;
180 	}
181 
182 	gid = v9fs_get_fsgid_for_create(dir);
183 
184 	mode = omode;
185 	/* Update mode based on ACL value */
186 	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
187 	if (err) {
188 		P9_DPRINTK(P9_DEBUG_VFS,
189 			   "Failed to get acl values in creat %d\n", err);
190 		goto error;
191 	}
192 	err = p9_client_create_dotl(ofid, name, flags, mode, gid, &qid);
193 	if (err < 0) {
194 		P9_DPRINTK(P9_DEBUG_VFS,
195 				"p9_client_open_dotl failed in creat %d\n",
196 				err);
197 		goto error;
198 	}
199 
200 	/* instantiate inode and assign the unopened fid to the dentry */
201 	fid = p9_client_walk(dfid, 1, &name, 1);
202 	if (IS_ERR(fid)) {
203 		err = PTR_ERR(fid);
204 		P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
205 		fid = NULL;
206 		goto error;
207 	}
208 	inode = v9fs_inode_from_fid(v9ses, fid, dir->i_sb);
209 	if (IS_ERR(inode)) {
210 		err = PTR_ERR(inode);
211 		P9_DPRINTK(P9_DEBUG_VFS, "inode creation failed %d\n", err);
212 		goto error;
213 	}
214 	d_instantiate(dentry, inode);
215 	err = v9fs_fid_add(dentry, fid);
216 	if (err < 0)
217 		goto error;
218 
219 	/* Now set the ACL based on the default value */
220 	v9fs_set_create_acl(dentry, dacl, pacl);
221 
222 	/* Since we are opening a file, assign the open fid to the file */
223 	filp = lookup_instantiate_filp(nd, dentry, generic_file_open);
224 	if (IS_ERR(filp)) {
225 		p9_client_clunk(ofid);
226 		return PTR_ERR(filp);
227 	}
228 	filp->private_data = ofid;
229 	return 0;
230 
231 error:
232 	if (ofid)
233 		p9_client_clunk(ofid);
234 	if (fid)
235 		p9_client_clunk(fid);
236 	return err;
237 }
238 
239 /**
240  * v9fs_vfs_mkdir_dotl - VFS mkdir hook to create a directory
241  * @dir:  inode that is being unlinked
242  * @dentry: dentry that is being unlinked
243  * @mode: mode for new directory
244  *
245  */
246 
247 static int v9fs_vfs_mkdir_dotl(struct inode *dir,
248 			       struct dentry *dentry, int omode)
249 {
250 	int err;
251 	struct v9fs_session_info *v9ses;
252 	struct p9_fid *fid = NULL, *dfid = NULL;
253 	gid_t gid;
254 	char *name;
255 	mode_t mode;
256 	struct inode *inode;
257 	struct p9_qid qid;
258 	struct dentry *dir_dentry;
259 	struct posix_acl *dacl = NULL, *pacl = NULL;
260 
261 	P9_DPRINTK(P9_DEBUG_VFS, "name %s\n", dentry->d_name.name);
262 	err = 0;
263 	v9ses = v9fs_inode2v9ses(dir);
264 
265 	omode |= S_IFDIR;
266 	if (dir->i_mode & S_ISGID)
267 		omode |= S_ISGID;
268 
269 	dir_dentry = v9fs_dentry_from_dir_inode(dir);
270 	dfid = v9fs_fid_lookup(dir_dentry);
271 	if (IS_ERR(dfid)) {
272 		err = PTR_ERR(dfid);
273 		P9_DPRINTK(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
274 		dfid = NULL;
275 		goto error;
276 	}
277 
278 	gid = v9fs_get_fsgid_for_create(dir);
279 	mode = omode;
280 	/* Update mode based on ACL value */
281 	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
282 	if (err) {
283 		P9_DPRINTK(P9_DEBUG_VFS,
284 			   "Failed to get acl values in mkdir %d\n", err);
285 		goto error;
286 	}
287 	name = (char *) dentry->d_name.name;
288 	err = p9_client_mkdir_dotl(dfid, name, mode, gid, &qid);
289 	if (err < 0)
290 		goto error;
291 
292 	/* instantiate inode and assign the unopened fid to the dentry */
293 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
294 		fid = p9_client_walk(dfid, 1, &name, 1);
295 		if (IS_ERR(fid)) {
296 			err = PTR_ERR(fid);
297 			P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
298 				err);
299 			fid = NULL;
300 			goto error;
301 		}
302 
303 		inode = v9fs_inode_from_fid(v9ses, fid, dir->i_sb);
304 		if (IS_ERR(inode)) {
305 			err = PTR_ERR(inode);
306 			P9_DPRINTK(P9_DEBUG_VFS, "inode creation failed %d\n",
307 				err);
308 			goto error;
309 		}
310 		d_instantiate(dentry, inode);
311 		err = v9fs_fid_add(dentry, fid);
312 		if (err < 0)
313 			goto error;
314 		fid = NULL;
315 	} else {
316 		/*
317 		 * Not in cached mode. No need to populate
318 		 * inode with stat. We need to get an inode
319 		 * so that we can set the acl with dentry
320 		 */
321 		inode = v9fs_get_inode(dir->i_sb, mode);
322 		if (IS_ERR(inode)) {
323 			err = PTR_ERR(inode);
324 			goto error;
325 		}
326 		d_instantiate(dentry, inode);
327 	}
328 	/* Now set the ACL based on the default value */
329 	v9fs_set_create_acl(dentry, dacl, pacl);
330 
331 error:
332 	if (fid)
333 		p9_client_clunk(fid);
334 	return err;
335 }
336 
337 static int
338 v9fs_vfs_getattr_dotl(struct vfsmount *mnt, struct dentry *dentry,
339 		 struct kstat *stat)
340 {
341 	int err;
342 	struct v9fs_session_info *v9ses;
343 	struct p9_fid *fid;
344 	struct p9_stat_dotl *st;
345 
346 	P9_DPRINTK(P9_DEBUG_VFS, "dentry: %p\n", dentry);
347 	err = -EPERM;
348 	v9ses = v9fs_inode2v9ses(dentry->d_inode);
349 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
350 		return simple_getattr(mnt, dentry, stat);
351 
352 	fid = v9fs_fid_lookup(dentry);
353 	if (IS_ERR(fid))
354 		return PTR_ERR(fid);
355 
356 	/* Ask for all the fields in stat structure. Server will return
357 	 * whatever it supports
358 	 */
359 
360 	st = p9_client_getattr_dotl(fid, P9_STATS_ALL);
361 	if (IS_ERR(st))
362 		return PTR_ERR(st);
363 
364 	v9fs_stat2inode_dotl(st, dentry->d_inode);
365 	generic_fillattr(dentry->d_inode, stat);
366 	/* Change block size to what the server returned */
367 	stat->blksize = st->st_blksize;
368 
369 	kfree(st);
370 	return 0;
371 }
372 
373 /**
374  * v9fs_vfs_setattr_dotl - set file metadata
375  * @dentry: file whose metadata to set
376  * @iattr: metadata assignment structure
377  *
378  */
379 
380 int v9fs_vfs_setattr_dotl(struct dentry *dentry, struct iattr *iattr)
381 {
382 	int retval;
383 	struct v9fs_session_info *v9ses;
384 	struct p9_fid *fid;
385 	struct p9_iattr_dotl p9attr;
386 
387 	P9_DPRINTK(P9_DEBUG_VFS, "\n");
388 
389 	retval = inode_change_ok(dentry->d_inode, iattr);
390 	if (retval)
391 		return retval;
392 
393 	p9attr.valid = iattr->ia_valid;
394 	p9attr.mode = iattr->ia_mode;
395 	p9attr.uid = iattr->ia_uid;
396 	p9attr.gid = iattr->ia_gid;
397 	p9attr.size = iattr->ia_size;
398 	p9attr.atime_sec = iattr->ia_atime.tv_sec;
399 	p9attr.atime_nsec = iattr->ia_atime.tv_nsec;
400 	p9attr.mtime_sec = iattr->ia_mtime.tv_sec;
401 	p9attr.mtime_nsec = iattr->ia_mtime.tv_nsec;
402 
403 	retval = -EPERM;
404 	v9ses = v9fs_inode2v9ses(dentry->d_inode);
405 	fid = v9fs_fid_lookup(dentry);
406 	if (IS_ERR(fid))
407 		return PTR_ERR(fid);
408 
409 	retval = p9_client_setattr(fid, &p9attr);
410 	if (retval < 0)
411 		return retval;
412 
413 	if ((iattr->ia_valid & ATTR_SIZE) &&
414 	    iattr->ia_size != i_size_read(dentry->d_inode)) {
415 		retval = vmtruncate(dentry->d_inode, iattr->ia_size);
416 		if (retval)
417 			return retval;
418 	}
419 
420 	setattr_copy(dentry->d_inode, iattr);
421 	mark_inode_dirty(dentry->d_inode);
422 	if (iattr->ia_valid & ATTR_MODE) {
423 		/* We also want to update ACL when we update mode bits */
424 		retval = v9fs_acl_chmod(dentry);
425 		if (retval < 0)
426 			return retval;
427 	}
428 	return 0;
429 }
430 
431 /**
432  * v9fs_stat2inode_dotl - populate an inode structure with stat info
433  * @stat: stat structure
434  * @inode: inode to populate
435  * @sb: superblock of filesystem
436  *
437  */
438 
439 void
440 v9fs_stat2inode_dotl(struct p9_stat_dotl *stat, struct inode *inode)
441 {
442 
443 	if ((stat->st_result_mask & P9_STATS_BASIC) == P9_STATS_BASIC) {
444 		inode->i_atime.tv_sec = stat->st_atime_sec;
445 		inode->i_atime.tv_nsec = stat->st_atime_nsec;
446 		inode->i_mtime.tv_sec = stat->st_mtime_sec;
447 		inode->i_mtime.tv_nsec = stat->st_mtime_nsec;
448 		inode->i_ctime.tv_sec = stat->st_ctime_sec;
449 		inode->i_ctime.tv_nsec = stat->st_ctime_nsec;
450 		inode->i_uid = stat->st_uid;
451 		inode->i_gid = stat->st_gid;
452 		inode->i_nlink = stat->st_nlink;
453 		inode->i_mode = stat->st_mode;
454 		inode->i_rdev = new_decode_dev(stat->st_rdev);
455 
456 		if ((S_ISBLK(inode->i_mode)) || (S_ISCHR(inode->i_mode)))
457 			init_special_inode(inode, inode->i_mode, inode->i_rdev);
458 
459 		i_size_write(inode, stat->st_size);
460 		inode->i_blocks = stat->st_blocks;
461 	} else {
462 		if (stat->st_result_mask & P9_STATS_ATIME) {
463 			inode->i_atime.tv_sec = stat->st_atime_sec;
464 			inode->i_atime.tv_nsec = stat->st_atime_nsec;
465 		}
466 		if (stat->st_result_mask & P9_STATS_MTIME) {
467 			inode->i_mtime.tv_sec = stat->st_mtime_sec;
468 			inode->i_mtime.tv_nsec = stat->st_mtime_nsec;
469 		}
470 		if (stat->st_result_mask & P9_STATS_CTIME) {
471 			inode->i_ctime.tv_sec = stat->st_ctime_sec;
472 			inode->i_ctime.tv_nsec = stat->st_ctime_nsec;
473 		}
474 		if (stat->st_result_mask & P9_STATS_UID)
475 			inode->i_uid = stat->st_uid;
476 		if (stat->st_result_mask & P9_STATS_GID)
477 			inode->i_gid = stat->st_gid;
478 		if (stat->st_result_mask & P9_STATS_NLINK)
479 			inode->i_nlink = stat->st_nlink;
480 		if (stat->st_result_mask & P9_STATS_MODE) {
481 			inode->i_mode = stat->st_mode;
482 			if ((S_ISBLK(inode->i_mode)) ||
483 						(S_ISCHR(inode->i_mode)))
484 				init_special_inode(inode, inode->i_mode,
485 								inode->i_rdev);
486 		}
487 		if (stat->st_result_mask & P9_STATS_RDEV)
488 			inode->i_rdev = new_decode_dev(stat->st_rdev);
489 		if (stat->st_result_mask & P9_STATS_SIZE)
490 			i_size_write(inode, stat->st_size);
491 		if (stat->st_result_mask & P9_STATS_BLOCKS)
492 			inode->i_blocks = stat->st_blocks;
493 	}
494 	if (stat->st_result_mask & P9_STATS_GEN)
495 			inode->i_generation = stat->st_gen;
496 
497 	/* Currently we don't support P9_STATS_BTIME and P9_STATS_DATA_VERSION
498 	 * because the inode structure does not have fields for them.
499 	 */
500 }
501 
502 static int
503 v9fs_vfs_symlink_dotl(struct inode *dir, struct dentry *dentry,
504 		const char *symname)
505 {
506 	struct v9fs_session_info *v9ses;
507 	struct p9_fid *dfid;
508 	struct p9_fid *fid = NULL;
509 	struct inode *inode;
510 	struct p9_qid qid;
511 	char *name;
512 	int err;
513 	gid_t gid;
514 
515 	name = (char *) dentry->d_name.name;
516 	P9_DPRINTK(P9_DEBUG_VFS, "v9fs_vfs_symlink_dotl : %lu,%s,%s\n",
517 			dir->i_ino, name, symname);
518 	v9ses = v9fs_inode2v9ses(dir);
519 
520 	dfid = v9fs_fid_lookup(dentry->d_parent);
521 	if (IS_ERR(dfid)) {
522 		err = PTR_ERR(dfid);
523 		P9_DPRINTK(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
524 		return err;
525 	}
526 
527 	gid = v9fs_get_fsgid_for_create(dir);
528 
529 	/* Server doesn't alter fid on TSYMLINK. Hence no need to clone it. */
530 	err = p9_client_symlink(dfid, name, (char *)symname, gid, &qid);
531 
532 	if (err < 0) {
533 		P9_DPRINTK(P9_DEBUG_VFS, "p9_client_symlink failed %d\n", err);
534 		goto error;
535 	}
536 
537 	if (v9ses->cache) {
538 		/* Now walk from the parent so we can get an unopened fid. */
539 		fid = p9_client_walk(dfid, 1, &name, 1);
540 		if (IS_ERR(fid)) {
541 			err = PTR_ERR(fid);
542 			P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
543 					err);
544 			fid = NULL;
545 			goto error;
546 		}
547 
548 		/* instantiate inode and assign the unopened fid to dentry */
549 		inode = v9fs_inode_from_fid(v9ses, fid, dir->i_sb);
550 		if (IS_ERR(inode)) {
551 			err = PTR_ERR(inode);
552 			P9_DPRINTK(P9_DEBUG_VFS, "inode creation failed %d\n",
553 					err);
554 			goto error;
555 		}
556 		d_instantiate(dentry, inode);
557 		err = v9fs_fid_add(dentry, fid);
558 		if (err < 0)
559 			goto error;
560 		fid = NULL;
561 	} else {
562 		/* Not in cached mode. No need to populate inode with stat */
563 		inode = v9fs_get_inode(dir->i_sb, S_IFLNK);
564 		if (IS_ERR(inode)) {
565 			err = PTR_ERR(inode);
566 			goto error;
567 		}
568 		d_instantiate(dentry, inode);
569 	}
570 
571 error:
572 	if (fid)
573 		p9_client_clunk(fid);
574 
575 	return err;
576 }
577 
578 /**
579  * v9fs_vfs_link_dotl - create a hardlink for dotl
580  * @old_dentry: dentry for file to link to
581  * @dir: inode destination for new link
582  * @dentry: dentry for link
583  *
584  */
585 
586 static int
587 v9fs_vfs_link_dotl(struct dentry *old_dentry, struct inode *dir,
588 		struct dentry *dentry)
589 {
590 	int err;
591 	struct p9_fid *dfid, *oldfid;
592 	char *name;
593 	struct v9fs_session_info *v9ses;
594 	struct dentry *dir_dentry;
595 
596 	P9_DPRINTK(P9_DEBUG_VFS, "dir ino: %lu, old_name: %s, new_name: %s\n",
597 			dir->i_ino, old_dentry->d_name.name,
598 			dentry->d_name.name);
599 
600 	v9ses = v9fs_inode2v9ses(dir);
601 	dir_dentry = v9fs_dentry_from_dir_inode(dir);
602 	dfid = v9fs_fid_lookup(dir_dentry);
603 	if (IS_ERR(dfid))
604 		return PTR_ERR(dfid);
605 
606 	oldfid = v9fs_fid_lookup(old_dentry);
607 	if (IS_ERR(oldfid))
608 		return PTR_ERR(oldfid);
609 
610 	name = (char *) dentry->d_name.name;
611 
612 	err = p9_client_link(dfid, oldfid, (char *)dentry->d_name.name);
613 
614 	if (err < 0) {
615 		P9_DPRINTK(P9_DEBUG_VFS, "p9_client_link failed %d\n", err);
616 		return err;
617 	}
618 
619 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
620 		/* Get the latest stat info from server. */
621 		struct p9_fid *fid;
622 		struct p9_stat_dotl *st;
623 
624 		fid = v9fs_fid_lookup(old_dentry);
625 		if (IS_ERR(fid))
626 			return PTR_ERR(fid);
627 
628 		st = p9_client_getattr_dotl(fid, P9_STATS_BASIC);
629 		if (IS_ERR(st))
630 			return PTR_ERR(st);
631 
632 		v9fs_stat2inode_dotl(st, old_dentry->d_inode);
633 
634 		kfree(st);
635 	} else {
636 		/* Caching disabled. No need to get upto date stat info.
637 		 * This dentry will be released immediately. So, just hold the
638 		 * inode
639 		 */
640 		ihold(old_dentry->d_inode);
641 	}
642 	d_instantiate(dentry, old_dentry->d_inode);
643 
644 	return err;
645 }
646 
647 /**
648  * v9fs_vfs_mknod_dotl - create a special file
649  * @dir: inode destination for new link
650  * @dentry: dentry for file
651  * @mode: mode for creation
652  * @rdev: device associated with special file
653  *
654  */
655 static int
656 v9fs_vfs_mknod_dotl(struct inode *dir, struct dentry *dentry, int omode,
657 		dev_t rdev)
658 {
659 	int err;
660 	char *name;
661 	mode_t mode;
662 	struct v9fs_session_info *v9ses;
663 	struct p9_fid *fid = NULL, *dfid = NULL;
664 	struct inode *inode;
665 	gid_t gid;
666 	struct p9_qid qid;
667 	struct dentry *dir_dentry;
668 	struct posix_acl *dacl = NULL, *pacl = NULL;
669 
670 	P9_DPRINTK(P9_DEBUG_VFS,
671 		" %lu,%s mode: %x MAJOR: %u MINOR: %u\n", dir->i_ino,
672 		dentry->d_name.name, omode, MAJOR(rdev), MINOR(rdev));
673 
674 	if (!new_valid_dev(rdev))
675 		return -EINVAL;
676 
677 	v9ses = v9fs_inode2v9ses(dir);
678 	dir_dentry = v9fs_dentry_from_dir_inode(dir);
679 	dfid = v9fs_fid_lookup(dir_dentry);
680 	if (IS_ERR(dfid)) {
681 		err = PTR_ERR(dfid);
682 		P9_DPRINTK(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
683 		dfid = NULL;
684 		goto error;
685 	}
686 
687 	gid = v9fs_get_fsgid_for_create(dir);
688 	mode = omode;
689 	/* Update mode based on ACL value */
690 	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
691 	if (err) {
692 		P9_DPRINTK(P9_DEBUG_VFS,
693 			   "Failed to get acl values in mknod %d\n", err);
694 		goto error;
695 	}
696 	name = (char *) dentry->d_name.name;
697 
698 	err = p9_client_mknod_dotl(dfid, name, mode, rdev, gid, &qid);
699 	if (err < 0)
700 		goto error;
701 
702 	/* instantiate inode and assign the unopened fid to the dentry */
703 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
704 		fid = p9_client_walk(dfid, 1, &name, 1);
705 		if (IS_ERR(fid)) {
706 			err = PTR_ERR(fid);
707 			P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
708 				err);
709 			fid = NULL;
710 			goto error;
711 		}
712 
713 		inode = v9fs_inode_from_fid(v9ses, fid, dir->i_sb);
714 		if (IS_ERR(inode)) {
715 			err = PTR_ERR(inode);
716 			P9_DPRINTK(P9_DEBUG_VFS, "inode creation failed %d\n",
717 				err);
718 			goto error;
719 		}
720 		d_instantiate(dentry, inode);
721 		err = v9fs_fid_add(dentry, fid);
722 		if (err < 0)
723 			goto error;
724 		fid = NULL;
725 	} else {
726 		/*
727 		 * Not in cached mode. No need to populate inode with stat.
728 		 * socket syscall returns a fd, so we need instantiate
729 		 */
730 		inode = v9fs_get_inode(dir->i_sb, mode);
731 		if (IS_ERR(inode)) {
732 			err = PTR_ERR(inode);
733 			goto error;
734 		}
735 		d_instantiate(dentry, inode);
736 	}
737 	/* Now set the ACL based on the default value */
738 	v9fs_set_create_acl(dentry, dacl, pacl);
739 error:
740 	if (fid)
741 		p9_client_clunk(fid);
742 	return err;
743 }
744 
745 /**
746  * v9fs_vfs_follow_link_dotl - follow a symlink path
747  * @dentry: dentry for symlink
748  * @nd: nameidata
749  *
750  */
751 
752 static void *
753 v9fs_vfs_follow_link_dotl(struct dentry *dentry, struct nameidata *nd)
754 {
755 	int retval;
756 	struct p9_fid *fid;
757 	char *link = __getname();
758 	char *target;
759 
760 	P9_DPRINTK(P9_DEBUG_VFS, "%s\n", dentry->d_name.name);
761 
762 	if (!link) {
763 		link = ERR_PTR(-ENOMEM);
764 		goto ndset;
765 	}
766 	fid = v9fs_fid_lookup(dentry);
767 	if (IS_ERR(fid)) {
768 		__putname(link);
769 		link = ERR_PTR(PTR_ERR(fid));
770 		goto ndset;
771 	}
772 	retval = p9_client_readlink(fid, &target);
773 	if (!retval) {
774 		strcpy(link, target);
775 		kfree(target);
776 		goto ndset;
777 	}
778 	__putname(link);
779 	link = ERR_PTR(retval);
780 ndset:
781 	nd_set_link(nd, link);
782 	return NULL;
783 }
784 
785 const struct inode_operations v9fs_dir_inode_operations_dotl = {
786 	.create = v9fs_vfs_create_dotl,
787 	.lookup = v9fs_vfs_lookup,
788 	.link = v9fs_vfs_link_dotl,
789 	.symlink = v9fs_vfs_symlink_dotl,
790 	.unlink = v9fs_vfs_unlink,
791 	.mkdir = v9fs_vfs_mkdir_dotl,
792 	.rmdir = v9fs_vfs_rmdir,
793 	.mknod = v9fs_vfs_mknod_dotl,
794 	.rename = v9fs_vfs_rename,
795 	.getattr = v9fs_vfs_getattr_dotl,
796 	.setattr = v9fs_vfs_setattr_dotl,
797 	.setxattr = generic_setxattr,
798 	.getxattr = generic_getxattr,
799 	.removexattr = generic_removexattr,
800 	.listxattr = v9fs_listxattr,
801 	.check_acl = v9fs_check_acl,
802 };
803 
804 const struct inode_operations v9fs_file_inode_operations_dotl = {
805 	.getattr = v9fs_vfs_getattr_dotl,
806 	.setattr = v9fs_vfs_setattr_dotl,
807 	.setxattr = generic_setxattr,
808 	.getxattr = generic_getxattr,
809 	.removexattr = generic_removexattr,
810 	.listxattr = v9fs_listxattr,
811 	.check_acl = v9fs_check_acl,
812 };
813 
814 const struct inode_operations v9fs_symlink_inode_operations_dotl = {
815 	.readlink = generic_readlink,
816 	.follow_link = v9fs_vfs_follow_link_dotl,
817 	.put_link = v9fs_vfs_put_link,
818 	.getattr = v9fs_vfs_getattr_dotl,
819 	.setattr = v9fs_vfs_setattr_dotl,
820 	.setxattr = generic_setxattr,
821 	.getxattr = generic_getxattr,
822 	.removexattr = generic_removexattr,
823 	.listxattr = v9fs_listxattr,
824 };
825