xref: /openbmc/linux/fs/9p/vfs_inode_dotl.c (revision 3ce7547e)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * This file contains vfs inode ops for the 9P2000.L protocol.
4  *
5  *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
6  *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
7  */
8 
9 #include <linux/module.h>
10 #include <linux/errno.h>
11 #include <linux/fs.h>
12 #include <linux/file.h>
13 #include <linux/pagemap.h>
14 #include <linux/stat.h>
15 #include <linux/string.h>
16 #include <linux/inet.h>
17 #include <linux/namei.h>
18 #include <linux/idr.h>
19 #include <linux/sched.h>
20 #include <linux/slab.h>
21 #include <linux/xattr.h>
22 #include <linux/posix_acl.h>
23 #include <net/9p/9p.h>
24 #include <net/9p/client.h>
25 
26 #include "v9fs.h"
27 #include "v9fs_vfs.h"
28 #include "fid.h"
29 #include "cache.h"
30 #include "xattr.h"
31 #include "acl.h"
32 
33 static int
34 v9fs_vfs_mknod_dotl(struct user_namespace *mnt_userns, struct inode *dir,
35 		    struct dentry *dentry, umode_t omode, dev_t rdev);
36 
37 /**
38  * v9fs_get_fsgid_for_create - Helper function to get the gid for a new object
39  * @dir_inode: The directory inode
40  *
41  * Helper function to get the gid for creating a
42  * new file system object. This checks the S_ISGID to determine the owning
43  * group of the new file system object.
44  */
45 
46 static kgid_t v9fs_get_fsgid_for_create(struct inode *dir_inode)
47 {
48 	BUG_ON(dir_inode == NULL);
49 
50 	if (dir_inode->i_mode & S_ISGID) {
51 		/* set_gid bit is set.*/
52 		return dir_inode->i_gid;
53 	}
54 	return current_fsgid();
55 }
56 
57 static int v9fs_test_inode_dotl(struct inode *inode, void *data)
58 {
59 	struct v9fs_inode *v9inode = V9FS_I(inode);
60 	struct p9_stat_dotl *st = (struct p9_stat_dotl *)data;
61 
62 	/* don't match inode of different type */
63 	if (inode_wrong_type(inode, st->st_mode))
64 		return 0;
65 
66 	if (inode->i_generation != st->st_gen)
67 		return 0;
68 
69 	/* compare qid details */
70 	if (memcmp(&v9inode->qid.version,
71 		   &st->qid.version, sizeof(v9inode->qid.version)))
72 		return 0;
73 
74 	if (v9inode->qid.type != st->qid.type)
75 		return 0;
76 
77 	if (v9inode->qid.path != st->qid.path)
78 		return 0;
79 	return 1;
80 }
81 
82 /* Always get a new inode */
83 static int v9fs_test_new_inode_dotl(struct inode *inode, void *data)
84 {
85 	return 0;
86 }
87 
88 static int v9fs_set_inode_dotl(struct inode *inode,  void *data)
89 {
90 	struct v9fs_inode *v9inode = V9FS_I(inode);
91 	struct p9_stat_dotl *st = (struct p9_stat_dotl *)data;
92 
93 	memcpy(&v9inode->qid, &st->qid, sizeof(st->qid));
94 	inode->i_generation = st->st_gen;
95 	return 0;
96 }
97 
98 static struct inode *v9fs_qid_iget_dotl(struct super_block *sb,
99 					struct p9_qid *qid,
100 					struct p9_fid *fid,
101 					struct p9_stat_dotl *st,
102 					int new)
103 {
104 	int retval;
105 	unsigned long i_ino;
106 	struct inode *inode;
107 	struct v9fs_session_info *v9ses = sb->s_fs_info;
108 	int (*test)(struct inode *inode, void *data);
109 
110 	if (new)
111 		test = v9fs_test_new_inode_dotl;
112 	else
113 		test = v9fs_test_inode_dotl;
114 
115 	i_ino = v9fs_qid2ino(qid);
116 	inode = iget5_locked(sb, i_ino, test, v9fs_set_inode_dotl, st);
117 	if (!inode)
118 		return ERR_PTR(-ENOMEM);
119 	if (!(inode->i_state & I_NEW))
120 		return inode;
121 	/*
122 	 * initialize the inode with the stat info
123 	 * FIXME!! we may need support for stale inodes
124 	 * later.
125 	 */
126 	inode->i_ino = i_ino;
127 	retval = v9fs_init_inode(v9ses, inode,
128 				 st->st_mode, new_decode_dev(st->st_rdev));
129 	if (retval)
130 		goto error;
131 
132 	v9fs_stat2inode_dotl(st, inode, 0);
133 	v9fs_cache_inode_get_cookie(inode);
134 	retval = v9fs_get_acl(inode, fid);
135 	if (retval)
136 		goto error;
137 
138 	unlock_new_inode(inode);
139 	return inode;
140 error:
141 	iget_failed(inode);
142 	return ERR_PTR(retval);
143 
144 }
145 
146 struct inode *
147 v9fs_inode_from_fid_dotl(struct v9fs_session_info *v9ses, struct p9_fid *fid,
148 			 struct super_block *sb, int new)
149 {
150 	struct p9_stat_dotl *st;
151 	struct inode *inode = NULL;
152 
153 	st = p9_client_getattr_dotl(fid, P9_STATS_BASIC | P9_STATS_GEN);
154 	if (IS_ERR(st))
155 		return ERR_CAST(st);
156 
157 	inode = v9fs_qid_iget_dotl(sb, &st->qid, fid, st, new);
158 	kfree(st);
159 	return inode;
160 }
161 
162 struct dotl_openflag_map {
163 	int open_flag;
164 	int dotl_flag;
165 };
166 
167 static int v9fs_mapped_dotl_flags(int flags)
168 {
169 	int i;
170 	int rflags = 0;
171 	struct dotl_openflag_map dotl_oflag_map[] = {
172 		{ O_CREAT,	P9_DOTL_CREATE },
173 		{ O_EXCL,	P9_DOTL_EXCL },
174 		{ O_NOCTTY,	P9_DOTL_NOCTTY },
175 		{ O_APPEND,	P9_DOTL_APPEND },
176 		{ O_NONBLOCK,	P9_DOTL_NONBLOCK },
177 		{ O_DSYNC,	P9_DOTL_DSYNC },
178 		{ FASYNC,	P9_DOTL_FASYNC },
179 		{ O_DIRECT,	P9_DOTL_DIRECT },
180 		{ O_LARGEFILE,	P9_DOTL_LARGEFILE },
181 		{ O_DIRECTORY,	P9_DOTL_DIRECTORY },
182 		{ O_NOFOLLOW,	P9_DOTL_NOFOLLOW },
183 		{ O_NOATIME,	P9_DOTL_NOATIME },
184 		{ O_CLOEXEC,	P9_DOTL_CLOEXEC },
185 		{ O_SYNC,	P9_DOTL_SYNC},
186 	};
187 	for (i = 0; i < ARRAY_SIZE(dotl_oflag_map); i++) {
188 		if (flags & dotl_oflag_map[i].open_flag)
189 			rflags |= dotl_oflag_map[i].dotl_flag;
190 	}
191 	return rflags;
192 }
193 
194 /**
195  * v9fs_open_to_dotl_flags- convert Linux specific open flags to
196  * plan 9 open flag.
197  * @flags: flags to convert
198  */
199 int v9fs_open_to_dotl_flags(int flags)
200 {
201 	int rflags = 0;
202 
203 	/*
204 	 * We have same bits for P9_DOTL_READONLY, P9_DOTL_WRONLY
205 	 * and P9_DOTL_NOACCESS
206 	 */
207 	rflags |= flags & O_ACCMODE;
208 	rflags |= v9fs_mapped_dotl_flags(flags);
209 
210 	return rflags;
211 }
212 
213 /**
214  * v9fs_vfs_create_dotl - VFS hook to create files for 9P2000.L protocol.
215  * @mnt_userns: The user namespace of the mount
216  * @dir: directory inode that is being created
217  * @dentry:  dentry that is being deleted
218  * @omode: create permissions
219  * @excl: True if the file must not yet exist
220  *
221  */
222 static int
223 v9fs_vfs_create_dotl(struct user_namespace *mnt_userns, struct inode *dir,
224 		     struct dentry *dentry, umode_t omode, bool excl)
225 {
226 	return v9fs_vfs_mknod_dotl(mnt_userns, dir, dentry, omode, 0);
227 }
228 
229 static int
230 v9fs_vfs_atomic_open_dotl(struct inode *dir, struct dentry *dentry,
231 			  struct file *file, unsigned int flags, umode_t omode)
232 {
233 	int err = 0;
234 	kgid_t gid;
235 	umode_t mode;
236 	const unsigned char *name = NULL;
237 	struct p9_qid qid;
238 	struct inode *inode;
239 	struct p9_fid *fid = NULL;
240 	struct v9fs_inode *v9inode;
241 	struct p9_fid *dfid, *ofid, *inode_fid;
242 	struct v9fs_session_info *v9ses;
243 	struct posix_acl *pacl = NULL, *dacl = NULL;
244 	struct dentry *res = NULL;
245 
246 	if (d_in_lookup(dentry)) {
247 		res = v9fs_vfs_lookup(dir, dentry, 0);
248 		if (IS_ERR(res))
249 			return PTR_ERR(res);
250 
251 		if (res)
252 			dentry = res;
253 	}
254 
255 	/* Only creates */
256 	if (!(flags & O_CREAT) || d_really_is_positive(dentry))
257 		return	finish_no_open(file, res);
258 
259 	v9ses = v9fs_inode2v9ses(dir);
260 
261 	name = dentry->d_name.name;
262 	p9_debug(P9_DEBUG_VFS, "name:%s flags:0x%x mode:0x%x\n",
263 		 name, flags, omode);
264 
265 	dfid = v9fs_parent_fid(dentry);
266 	if (IS_ERR(dfid)) {
267 		err = PTR_ERR(dfid);
268 		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
269 		goto out;
270 	}
271 
272 	/* clone a fid to use for creation */
273 	ofid = clone_fid(dfid);
274 	if (IS_ERR(ofid)) {
275 		err = PTR_ERR(ofid);
276 		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
277 		p9_client_clunk(dfid);
278 		goto out;
279 	}
280 
281 	gid = v9fs_get_fsgid_for_create(dir);
282 
283 	mode = omode;
284 	/* Update mode based on ACL value */
285 	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
286 	if (err) {
287 		p9_debug(P9_DEBUG_VFS, "Failed to get acl values in creat %d\n",
288 			 err);
289 		p9_client_clunk(dfid);
290 		goto error;
291 	}
292 	err = p9_client_create_dotl(ofid, name, v9fs_open_to_dotl_flags(flags),
293 				    mode, gid, &qid);
294 	if (err < 0) {
295 		p9_debug(P9_DEBUG_VFS, "p9_client_open_dotl failed in creat %d\n",
296 			 err);
297 		p9_client_clunk(dfid);
298 		goto error;
299 	}
300 	v9fs_invalidate_inode_attr(dir);
301 
302 	/* instantiate inode and assign the unopened fid to the dentry */
303 	fid = p9_client_walk(dfid, 1, &name, 1);
304 	p9_client_clunk(dfid);
305 	if (IS_ERR(fid)) {
306 		err = PTR_ERR(fid);
307 		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
308 		fid = NULL;
309 		goto error;
310 	}
311 	inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
312 	if (IS_ERR(inode)) {
313 		err = PTR_ERR(inode);
314 		p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n", err);
315 		goto error;
316 	}
317 	/* Now set the ACL based on the default value */
318 	v9fs_set_create_acl(inode, fid, dacl, pacl);
319 
320 	v9fs_fid_add(dentry, fid);
321 	d_instantiate(dentry, inode);
322 
323 	v9inode = V9FS_I(inode);
324 	mutex_lock(&v9inode->v_mutex);
325 	if ((v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) &&
326 	    !v9inode->writeback_fid &&
327 	    ((flags & O_ACCMODE) != O_RDONLY)) {
328 		/*
329 		 * clone a fid and add it to writeback_fid
330 		 * we do it during open time instead of
331 		 * page dirty time via write_begin/page_mkwrite
332 		 * because we want write after unlink usecase
333 		 * to work.
334 		 */
335 		inode_fid = v9fs_writeback_fid(dentry);
336 		if (IS_ERR(inode_fid)) {
337 			err = PTR_ERR(inode_fid);
338 			mutex_unlock(&v9inode->v_mutex);
339 			goto err_clunk_old_fid;
340 		}
341 		v9inode->writeback_fid = (void *) inode_fid;
342 	}
343 	mutex_unlock(&v9inode->v_mutex);
344 	/* Since we are opening a file, assign the open fid to the file */
345 	err = finish_open(file, dentry, generic_file_open);
346 	if (err)
347 		goto err_clunk_old_fid;
348 	file->private_data = ofid;
349 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
350 		fscache_use_cookie(v9fs_inode_cookie(v9inode),
351 				   file->f_mode & FMODE_WRITE);
352 	v9fs_open_fid_add(inode, ofid);
353 	file->f_mode |= FMODE_CREATED;
354 out:
355 	v9fs_put_acl(dacl, pacl);
356 	dput(res);
357 	return err;
358 
359 error:
360 	if (fid)
361 		p9_client_clunk(fid);
362 err_clunk_old_fid:
363 	if (ofid)
364 		p9_client_clunk(ofid);
365 	goto out;
366 }
367 
368 /**
369  * v9fs_vfs_mkdir_dotl - VFS mkdir hook to create a directory
370  * @mnt_userns: The user namespace of the mount
371  * @dir:  inode that is being unlinked
372  * @dentry: dentry that is being unlinked
373  * @omode: mode for new directory
374  *
375  */
376 
377 static int v9fs_vfs_mkdir_dotl(struct user_namespace *mnt_userns,
378 			       struct inode *dir, struct dentry *dentry,
379 			       umode_t omode)
380 {
381 	int err;
382 	struct v9fs_session_info *v9ses;
383 	struct p9_fid *fid = NULL, *dfid = NULL;
384 	kgid_t gid;
385 	const unsigned char *name;
386 	umode_t mode;
387 	struct inode *inode;
388 	struct p9_qid qid;
389 	struct posix_acl *dacl = NULL, *pacl = NULL;
390 
391 	p9_debug(P9_DEBUG_VFS, "name %pd\n", dentry);
392 	err = 0;
393 	v9ses = v9fs_inode2v9ses(dir);
394 
395 	omode |= S_IFDIR;
396 	if (dir->i_mode & S_ISGID)
397 		omode |= S_ISGID;
398 
399 	dfid = v9fs_parent_fid(dentry);
400 	if (IS_ERR(dfid)) {
401 		err = PTR_ERR(dfid);
402 		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
403 		dfid = NULL;
404 		goto error;
405 	}
406 
407 	gid = v9fs_get_fsgid_for_create(dir);
408 	mode = omode;
409 	/* Update mode based on ACL value */
410 	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
411 	if (err) {
412 		p9_debug(P9_DEBUG_VFS, "Failed to get acl values in mkdir %d\n",
413 			 err);
414 		goto error;
415 	}
416 	name = dentry->d_name.name;
417 	err = p9_client_mkdir_dotl(dfid, name, mode, gid, &qid);
418 	if (err < 0)
419 		goto error;
420 	fid = p9_client_walk(dfid, 1, &name, 1);
421 	if (IS_ERR(fid)) {
422 		err = PTR_ERR(fid);
423 		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
424 			 err);
425 		fid = NULL;
426 		goto error;
427 	}
428 
429 	/* instantiate inode and assign the unopened fid to the dentry */
430 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
431 		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
432 		if (IS_ERR(inode)) {
433 			err = PTR_ERR(inode);
434 			p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n",
435 				 err);
436 			goto error;
437 		}
438 		v9fs_fid_add(dentry, fid);
439 		v9fs_set_create_acl(inode, fid, dacl, pacl);
440 		d_instantiate(dentry, inode);
441 		fid = NULL;
442 		err = 0;
443 	} else {
444 		/*
445 		 * Not in cached mode. No need to populate
446 		 * inode with stat. We need to get an inode
447 		 * so that we can set the acl with dentry
448 		 */
449 		inode = v9fs_get_inode(dir->i_sb, mode, 0);
450 		if (IS_ERR(inode)) {
451 			err = PTR_ERR(inode);
452 			goto error;
453 		}
454 		v9fs_set_create_acl(inode, fid, dacl, pacl);
455 		d_instantiate(dentry, inode);
456 	}
457 	inc_nlink(dir);
458 	v9fs_invalidate_inode_attr(dir);
459 error:
460 	if (fid)
461 		p9_client_clunk(fid);
462 	v9fs_put_acl(dacl, pacl);
463 	p9_client_clunk(dfid);
464 	return err;
465 }
466 
467 static int
468 v9fs_vfs_getattr_dotl(struct user_namespace *mnt_userns,
469 		      const struct path *path, struct kstat *stat,
470 		      u32 request_mask, unsigned int flags)
471 {
472 	struct dentry *dentry = path->dentry;
473 	struct v9fs_session_info *v9ses;
474 	struct p9_fid *fid;
475 	struct p9_stat_dotl *st;
476 
477 	p9_debug(P9_DEBUG_VFS, "dentry: %p\n", dentry);
478 	v9ses = v9fs_dentry2v9ses(dentry);
479 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
480 		generic_fillattr(&init_user_ns, d_inode(dentry), stat);
481 		return 0;
482 	}
483 	fid = v9fs_fid_lookup(dentry);
484 	if (IS_ERR(fid))
485 		return PTR_ERR(fid);
486 
487 	/* Ask for all the fields in stat structure. Server will return
488 	 * whatever it supports
489 	 */
490 
491 	st = p9_client_getattr_dotl(fid, P9_STATS_ALL);
492 	p9_client_clunk(fid);
493 	if (IS_ERR(st))
494 		return PTR_ERR(st);
495 
496 	v9fs_stat2inode_dotl(st, d_inode(dentry), 0);
497 	generic_fillattr(&init_user_ns, d_inode(dentry), stat);
498 	/* Change block size to what the server returned */
499 	stat->blksize = st->st_blksize;
500 
501 	kfree(st);
502 	return 0;
503 }
504 
505 /*
506  * Attribute flags.
507  */
508 #define P9_ATTR_MODE		(1 << 0)
509 #define P9_ATTR_UID		(1 << 1)
510 #define P9_ATTR_GID		(1 << 2)
511 #define P9_ATTR_SIZE		(1 << 3)
512 #define P9_ATTR_ATIME		(1 << 4)
513 #define P9_ATTR_MTIME		(1 << 5)
514 #define P9_ATTR_CTIME		(1 << 6)
515 #define P9_ATTR_ATIME_SET	(1 << 7)
516 #define P9_ATTR_MTIME_SET	(1 << 8)
517 
518 struct dotl_iattr_map {
519 	int iattr_valid;
520 	int p9_iattr_valid;
521 };
522 
523 static int v9fs_mapped_iattr_valid(int iattr_valid)
524 {
525 	int i;
526 	int p9_iattr_valid = 0;
527 	struct dotl_iattr_map dotl_iattr_map[] = {
528 		{ ATTR_MODE,		P9_ATTR_MODE },
529 		{ ATTR_UID,		P9_ATTR_UID },
530 		{ ATTR_GID,		P9_ATTR_GID },
531 		{ ATTR_SIZE,		P9_ATTR_SIZE },
532 		{ ATTR_ATIME,		P9_ATTR_ATIME },
533 		{ ATTR_MTIME,		P9_ATTR_MTIME },
534 		{ ATTR_CTIME,		P9_ATTR_CTIME },
535 		{ ATTR_ATIME_SET,	P9_ATTR_ATIME_SET },
536 		{ ATTR_MTIME_SET,	P9_ATTR_MTIME_SET },
537 	};
538 	for (i = 0; i < ARRAY_SIZE(dotl_iattr_map); i++) {
539 		if (iattr_valid & dotl_iattr_map[i].iattr_valid)
540 			p9_iattr_valid |= dotl_iattr_map[i].p9_iattr_valid;
541 	}
542 	return p9_iattr_valid;
543 }
544 
545 /**
546  * v9fs_vfs_setattr_dotl - set file metadata
547  * @mnt_userns: The user namespace of the mount
548  * @dentry: file whose metadata to set
549  * @iattr: metadata assignment structure
550  *
551  */
552 
553 int v9fs_vfs_setattr_dotl(struct user_namespace *mnt_userns,
554 			  struct dentry *dentry, struct iattr *iattr)
555 {
556 	int retval, use_dentry = 0;
557 	struct p9_fid *fid = NULL;
558 	struct p9_iattr_dotl p9attr = {
559 		.uid = INVALID_UID,
560 		.gid = INVALID_GID,
561 	};
562 	struct inode *inode = d_inode(dentry);
563 
564 	p9_debug(P9_DEBUG_VFS, "\n");
565 
566 	retval = setattr_prepare(&init_user_ns, dentry, iattr);
567 	if (retval)
568 		return retval;
569 
570 	p9attr.valid = v9fs_mapped_iattr_valid(iattr->ia_valid);
571 	if (iattr->ia_valid & ATTR_MODE)
572 		p9attr.mode = iattr->ia_mode;
573 	if (iattr->ia_valid & ATTR_UID)
574 		p9attr.uid = iattr->ia_uid;
575 	if (iattr->ia_valid & ATTR_GID)
576 		p9attr.gid = iattr->ia_gid;
577 	if (iattr->ia_valid & ATTR_SIZE)
578 		p9attr.size = iattr->ia_size;
579 	if (iattr->ia_valid & ATTR_ATIME_SET) {
580 		p9attr.atime_sec = iattr->ia_atime.tv_sec;
581 		p9attr.atime_nsec = iattr->ia_atime.tv_nsec;
582 	}
583 	if (iattr->ia_valid & ATTR_MTIME_SET) {
584 		p9attr.mtime_sec = iattr->ia_mtime.tv_sec;
585 		p9attr.mtime_nsec = iattr->ia_mtime.tv_nsec;
586 	}
587 
588 	if (iattr->ia_valid & ATTR_FILE) {
589 		fid = iattr->ia_file->private_data;
590 		WARN_ON(!fid);
591 	}
592 	if (!fid) {
593 		fid = v9fs_fid_lookup(dentry);
594 		use_dentry = 1;
595 	}
596 	if (IS_ERR(fid))
597 		return PTR_ERR(fid);
598 
599 	/* Write all dirty data */
600 	if (S_ISREG(inode->i_mode))
601 		filemap_write_and_wait(inode->i_mapping);
602 
603 	retval = p9_client_setattr(fid, &p9attr);
604 	if (retval < 0) {
605 		if (use_dentry)
606 			p9_client_clunk(fid);
607 		return retval;
608 	}
609 
610 	if ((iattr->ia_valid & ATTR_SIZE) &&
611 	    iattr->ia_size != i_size_read(inode))
612 		truncate_setsize(inode, iattr->ia_size);
613 
614 	v9fs_invalidate_inode_attr(inode);
615 	setattr_copy(&init_user_ns, inode, iattr);
616 	mark_inode_dirty(inode);
617 	if (iattr->ia_valid & ATTR_MODE) {
618 		/* We also want to update ACL when we update mode bits */
619 		retval = v9fs_acl_chmod(inode, fid);
620 		if (retval < 0) {
621 			if (use_dentry)
622 				p9_client_clunk(fid);
623 			return retval;
624 		}
625 	}
626 	if (use_dentry)
627 		p9_client_clunk(fid);
628 
629 	return 0;
630 }
631 
632 /**
633  * v9fs_stat2inode_dotl - populate an inode structure with stat info
634  * @stat: stat structure
635  * @inode: inode to populate
636  * @flags: ctrl flags (e.g. V9FS_STAT2INODE_KEEP_ISIZE)
637  *
638  */
639 
640 void
641 v9fs_stat2inode_dotl(struct p9_stat_dotl *stat, struct inode *inode,
642 		      unsigned int flags)
643 {
644 	umode_t mode;
645 	struct v9fs_inode *v9inode = V9FS_I(inode);
646 
647 	if ((stat->st_result_mask & P9_STATS_BASIC) == P9_STATS_BASIC) {
648 		inode->i_atime.tv_sec = stat->st_atime_sec;
649 		inode->i_atime.tv_nsec = stat->st_atime_nsec;
650 		inode->i_mtime.tv_sec = stat->st_mtime_sec;
651 		inode->i_mtime.tv_nsec = stat->st_mtime_nsec;
652 		inode->i_ctime.tv_sec = stat->st_ctime_sec;
653 		inode->i_ctime.tv_nsec = stat->st_ctime_nsec;
654 		inode->i_uid = stat->st_uid;
655 		inode->i_gid = stat->st_gid;
656 		set_nlink(inode, stat->st_nlink);
657 
658 		mode = stat->st_mode & S_IALLUGO;
659 		mode |= inode->i_mode & ~S_IALLUGO;
660 		inode->i_mode = mode;
661 
662 		if (!(flags & V9FS_STAT2INODE_KEEP_ISIZE))
663 			v9fs_i_size_write(inode, stat->st_size);
664 		inode->i_blocks = stat->st_blocks;
665 	} else {
666 		if (stat->st_result_mask & P9_STATS_ATIME) {
667 			inode->i_atime.tv_sec = stat->st_atime_sec;
668 			inode->i_atime.tv_nsec = stat->st_atime_nsec;
669 		}
670 		if (stat->st_result_mask & P9_STATS_MTIME) {
671 			inode->i_mtime.tv_sec = stat->st_mtime_sec;
672 			inode->i_mtime.tv_nsec = stat->st_mtime_nsec;
673 		}
674 		if (stat->st_result_mask & P9_STATS_CTIME) {
675 			inode->i_ctime.tv_sec = stat->st_ctime_sec;
676 			inode->i_ctime.tv_nsec = stat->st_ctime_nsec;
677 		}
678 		if (stat->st_result_mask & P9_STATS_UID)
679 			inode->i_uid = stat->st_uid;
680 		if (stat->st_result_mask & P9_STATS_GID)
681 			inode->i_gid = stat->st_gid;
682 		if (stat->st_result_mask & P9_STATS_NLINK)
683 			set_nlink(inode, stat->st_nlink);
684 		if (stat->st_result_mask & P9_STATS_MODE) {
685 			mode = stat->st_mode & S_IALLUGO;
686 			mode |= inode->i_mode & ~S_IALLUGO;
687 			inode->i_mode = mode;
688 		}
689 		if (!(flags & V9FS_STAT2INODE_KEEP_ISIZE) &&
690 		    stat->st_result_mask & P9_STATS_SIZE)
691 			v9fs_i_size_write(inode, stat->st_size);
692 		if (stat->st_result_mask & P9_STATS_BLOCKS)
693 			inode->i_blocks = stat->st_blocks;
694 	}
695 	if (stat->st_result_mask & P9_STATS_GEN)
696 		inode->i_generation = stat->st_gen;
697 
698 	/* Currently we don't support P9_STATS_BTIME and P9_STATS_DATA_VERSION
699 	 * because the inode structure does not have fields for them.
700 	 */
701 	v9inode->cache_validity &= ~V9FS_INO_INVALID_ATTR;
702 }
703 
704 static int
705 v9fs_vfs_symlink_dotl(struct user_namespace *mnt_userns, struct inode *dir,
706 		      struct dentry *dentry, const char *symname)
707 {
708 	int err;
709 	kgid_t gid;
710 	const unsigned char *name;
711 	struct p9_qid qid;
712 	struct inode *inode;
713 	struct p9_fid *dfid;
714 	struct p9_fid *fid = NULL;
715 	struct v9fs_session_info *v9ses;
716 
717 	name = dentry->d_name.name;
718 	p9_debug(P9_DEBUG_VFS, "%lu,%s,%s\n", dir->i_ino, name, symname);
719 	v9ses = v9fs_inode2v9ses(dir);
720 
721 	dfid = v9fs_parent_fid(dentry);
722 	if (IS_ERR(dfid)) {
723 		err = PTR_ERR(dfid);
724 		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
725 		return err;
726 	}
727 
728 	gid = v9fs_get_fsgid_for_create(dir);
729 
730 	/* Server doesn't alter fid on TSYMLINK. Hence no need to clone it. */
731 	err = p9_client_symlink(dfid, name, symname, gid, &qid);
732 
733 	if (err < 0) {
734 		p9_debug(P9_DEBUG_VFS, "p9_client_symlink failed %d\n", err);
735 		goto error;
736 	}
737 
738 	v9fs_invalidate_inode_attr(dir);
739 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
740 		/* Now walk from the parent so we can get an unopened fid. */
741 		fid = p9_client_walk(dfid, 1, &name, 1);
742 		if (IS_ERR(fid)) {
743 			err = PTR_ERR(fid);
744 			p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
745 				 err);
746 			fid = NULL;
747 			goto error;
748 		}
749 
750 		/* instantiate inode and assign the unopened fid to dentry */
751 		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
752 		if (IS_ERR(inode)) {
753 			err = PTR_ERR(inode);
754 			p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n",
755 				 err);
756 			goto error;
757 		}
758 		v9fs_fid_add(dentry, fid);
759 		d_instantiate(dentry, inode);
760 		fid = NULL;
761 		err = 0;
762 	} else {
763 		/* Not in cached mode. No need to populate inode with stat */
764 		inode = v9fs_get_inode(dir->i_sb, S_IFLNK, 0);
765 		if (IS_ERR(inode)) {
766 			err = PTR_ERR(inode);
767 			goto error;
768 		}
769 		d_instantiate(dentry, inode);
770 	}
771 
772 error:
773 	if (fid)
774 		p9_client_clunk(fid);
775 
776 	p9_client_clunk(dfid);
777 	return err;
778 }
779 
780 /**
781  * v9fs_vfs_link_dotl - create a hardlink for dotl
782  * @old_dentry: dentry for file to link to
783  * @dir: inode destination for new link
784  * @dentry: dentry for link
785  *
786  */
787 
788 static int
789 v9fs_vfs_link_dotl(struct dentry *old_dentry, struct inode *dir,
790 		struct dentry *dentry)
791 {
792 	int err;
793 	struct p9_fid *dfid, *oldfid;
794 	struct v9fs_session_info *v9ses;
795 
796 	p9_debug(P9_DEBUG_VFS, "dir ino: %lu, old_name: %pd, new_name: %pd\n",
797 		 dir->i_ino, old_dentry, dentry);
798 
799 	v9ses = v9fs_inode2v9ses(dir);
800 	dfid = v9fs_parent_fid(dentry);
801 	if (IS_ERR(dfid))
802 		return PTR_ERR(dfid);
803 
804 	oldfid = v9fs_fid_lookup(old_dentry);
805 	if (IS_ERR(oldfid)) {
806 		p9_client_clunk(dfid);
807 		return PTR_ERR(oldfid);
808 	}
809 
810 	err = p9_client_link(dfid, oldfid, dentry->d_name.name);
811 
812 	p9_client_clunk(dfid);
813 	p9_client_clunk(oldfid);
814 	if (err < 0) {
815 		p9_debug(P9_DEBUG_VFS, "p9_client_link failed %d\n", err);
816 		return err;
817 	}
818 
819 	v9fs_invalidate_inode_attr(dir);
820 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
821 		/* Get the latest stat info from server. */
822 		struct p9_fid *fid;
823 
824 		fid = v9fs_fid_lookup(old_dentry);
825 		if (IS_ERR(fid))
826 			return PTR_ERR(fid);
827 
828 		v9fs_refresh_inode_dotl(fid, d_inode(old_dentry));
829 		p9_client_clunk(fid);
830 	}
831 	ihold(d_inode(old_dentry));
832 	d_instantiate(dentry, d_inode(old_dentry));
833 
834 	return err;
835 }
836 
837 /**
838  * v9fs_vfs_mknod_dotl - create a special file
839  * @mnt_userns: The user namespace of the mount
840  * @dir: inode destination for new link
841  * @dentry: dentry for file
842  * @omode: mode for creation
843  * @rdev: device associated with special file
844  *
845  */
846 static int
847 v9fs_vfs_mknod_dotl(struct user_namespace *mnt_userns, struct inode *dir,
848 		    struct dentry *dentry, umode_t omode, dev_t rdev)
849 {
850 	int err;
851 	kgid_t gid;
852 	const unsigned char *name;
853 	umode_t mode;
854 	struct v9fs_session_info *v9ses;
855 	struct p9_fid *fid = NULL, *dfid = NULL;
856 	struct inode *inode;
857 	struct p9_qid qid;
858 	struct posix_acl *dacl = NULL, *pacl = NULL;
859 
860 	p9_debug(P9_DEBUG_VFS, " %lu,%pd mode: %x MAJOR: %u MINOR: %u\n",
861 		 dir->i_ino, dentry, omode,
862 		 MAJOR(rdev), MINOR(rdev));
863 
864 	v9ses = v9fs_inode2v9ses(dir);
865 	dfid = v9fs_parent_fid(dentry);
866 	if (IS_ERR(dfid)) {
867 		err = PTR_ERR(dfid);
868 		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
869 		dfid = NULL;
870 		goto error;
871 	}
872 
873 	gid = v9fs_get_fsgid_for_create(dir);
874 	mode = omode;
875 	/* Update mode based on ACL value */
876 	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
877 	if (err) {
878 		p9_debug(P9_DEBUG_VFS, "Failed to get acl values in mknod %d\n",
879 			 err);
880 		goto error;
881 	}
882 	name = dentry->d_name.name;
883 
884 	err = p9_client_mknod_dotl(dfid, name, mode, rdev, gid, &qid);
885 	if (err < 0)
886 		goto error;
887 
888 	v9fs_invalidate_inode_attr(dir);
889 	fid = p9_client_walk(dfid, 1, &name, 1);
890 	if (IS_ERR(fid)) {
891 		err = PTR_ERR(fid);
892 		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
893 			 err);
894 		fid = NULL;
895 		goto error;
896 	}
897 
898 	/* instantiate inode and assign the unopened fid to the dentry */
899 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
900 		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
901 		if (IS_ERR(inode)) {
902 			err = PTR_ERR(inode);
903 			p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n",
904 				 err);
905 			goto error;
906 		}
907 		v9fs_set_create_acl(inode, fid, dacl, pacl);
908 		v9fs_fid_add(dentry, fid);
909 		d_instantiate(dentry, inode);
910 		fid = NULL;
911 		err = 0;
912 	} else {
913 		/*
914 		 * Not in cached mode. No need to populate inode with stat.
915 		 * socket syscall returns a fd, so we need instantiate
916 		 */
917 		inode = v9fs_get_inode(dir->i_sb, mode, rdev);
918 		if (IS_ERR(inode)) {
919 			err = PTR_ERR(inode);
920 			goto error;
921 		}
922 		v9fs_set_create_acl(inode, fid, dacl, pacl);
923 		d_instantiate(dentry, inode);
924 	}
925 error:
926 	if (fid)
927 		p9_client_clunk(fid);
928 	v9fs_put_acl(dacl, pacl);
929 	p9_client_clunk(dfid);
930 
931 	return err;
932 }
933 
934 /**
935  * v9fs_vfs_get_link_dotl - follow a symlink path
936  * @dentry: dentry for symlink
937  * @inode: inode for symlink
938  * @done: destructor for return value
939  */
940 
941 static const char *
942 v9fs_vfs_get_link_dotl(struct dentry *dentry,
943 		       struct inode *inode,
944 		       struct delayed_call *done)
945 {
946 	struct p9_fid *fid;
947 	char *target;
948 	int retval;
949 
950 	if (!dentry)
951 		return ERR_PTR(-ECHILD);
952 
953 	p9_debug(P9_DEBUG_VFS, "%pd\n", dentry);
954 
955 	fid = v9fs_fid_lookup(dentry);
956 	if (IS_ERR(fid))
957 		return ERR_CAST(fid);
958 	retval = p9_client_readlink(fid, &target);
959 	p9_client_clunk(fid);
960 	if (retval)
961 		return ERR_PTR(retval);
962 	set_delayed_call(done, kfree_link, target);
963 	return target;
964 }
965 
966 int v9fs_refresh_inode_dotl(struct p9_fid *fid, struct inode *inode)
967 {
968 	struct p9_stat_dotl *st;
969 	struct v9fs_session_info *v9ses;
970 	unsigned int flags;
971 
972 	v9ses = v9fs_inode2v9ses(inode);
973 	st = p9_client_getattr_dotl(fid, P9_STATS_ALL);
974 	if (IS_ERR(st))
975 		return PTR_ERR(st);
976 	/*
977 	 * Don't update inode if the file type is different
978 	 */
979 	if (inode_wrong_type(inode, st->st_mode))
980 		goto out;
981 
982 	/*
983 	 * We don't want to refresh inode->i_size,
984 	 * because we may have cached data
985 	 */
986 	flags = (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) ?
987 		V9FS_STAT2INODE_KEEP_ISIZE : 0;
988 	v9fs_stat2inode_dotl(st, inode, flags);
989 out:
990 	kfree(st);
991 	return 0;
992 }
993 
994 const struct inode_operations v9fs_dir_inode_operations_dotl = {
995 	.create = v9fs_vfs_create_dotl,
996 	.atomic_open = v9fs_vfs_atomic_open_dotl,
997 	.lookup = v9fs_vfs_lookup,
998 	.link = v9fs_vfs_link_dotl,
999 	.symlink = v9fs_vfs_symlink_dotl,
1000 	.unlink = v9fs_vfs_unlink,
1001 	.mkdir = v9fs_vfs_mkdir_dotl,
1002 	.rmdir = v9fs_vfs_rmdir,
1003 	.mknod = v9fs_vfs_mknod_dotl,
1004 	.rename = v9fs_vfs_rename,
1005 	.getattr = v9fs_vfs_getattr_dotl,
1006 	.setattr = v9fs_vfs_setattr_dotl,
1007 	.listxattr = v9fs_listxattr,
1008 	.get_acl = v9fs_iop_get_acl,
1009 };
1010 
1011 const struct inode_operations v9fs_file_inode_operations_dotl = {
1012 	.getattr = v9fs_vfs_getattr_dotl,
1013 	.setattr = v9fs_vfs_setattr_dotl,
1014 	.listxattr = v9fs_listxattr,
1015 	.get_acl = v9fs_iop_get_acl,
1016 };
1017 
1018 const struct inode_operations v9fs_symlink_inode_operations_dotl = {
1019 	.get_link = v9fs_vfs_get_link_dotl,
1020 	.getattr = v9fs_vfs_getattr_dotl,
1021 	.setattr = v9fs_vfs_setattr_dotl,
1022 	.listxattr = v9fs_listxattr,
1023 };
1024