xref: /linux/fs/9p/vfs_inode_dotl.c (revision f2527d8f566a45fa00ee5abd04d1c9476d4d704f)
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/sched.h>
19 #include <linux/slab.h>
20 #include <linux/xattr.h>
21 #include <linux/posix_acl.h>
22 #include <net/9p/9p.h>
23 #include <net/9p/client.h>
24 
25 #include "v9fs.h"
26 #include "v9fs_vfs.h"
27 #include "fid.h"
28 #include "cache.h"
29 #include "xattr.h"
30 #include "acl.h"
31 
32 static int
33 v9fs_vfs_mknod_dotl(struct user_namespace *mnt_userns, struct inode *dir,
34 		    struct dentry *dentry, umode_t omode, dev_t rdev);
35 
36 /**
37  * v9fs_get_fsgid_for_create - Helper function to get the gid for a new object
38  * @dir_inode: The directory inode
39  *
40  * Helper function to get the gid for creating a
41  * new file system object. This checks the S_ISGID to determine the owning
42  * group of the new file system object.
43  */
44 
45 static kgid_t v9fs_get_fsgid_for_create(struct inode *dir_inode)
46 {
47 	BUG_ON(dir_inode == NULL);
48 
49 	if (dir_inode->i_mode & S_ISGID) {
50 		/* set_gid bit is set.*/
51 		return dir_inode->i_gid;
52 	}
53 	return current_fsgid();
54 }
55 
56 static int v9fs_test_inode_dotl(struct inode *inode, void *data)
57 {
58 	struct v9fs_inode *v9inode = V9FS_I(inode);
59 	struct p9_stat_dotl *st = (struct p9_stat_dotl *)data;
60 
61 	/* don't match inode of different type */
62 	if (inode_wrong_type(inode, st->st_mode))
63 		return 0;
64 
65 	if (inode->i_generation != st->st_gen)
66 		return 0;
67 
68 	/* compare qid details */
69 	if (memcmp(&v9inode->qid.version,
70 		   &st->qid.version, sizeof(v9inode->qid.version)))
71 		return 0;
72 
73 	if (v9inode->qid.type != st->qid.type)
74 		return 0;
75 
76 	if (v9inode->qid.path != st->qid.path)
77 		return 0;
78 	return 1;
79 }
80 
81 /* Always get a new inode */
82 static int v9fs_test_new_inode_dotl(struct inode *inode, void *data)
83 {
84 	return 0;
85 }
86 
87 static int v9fs_set_inode_dotl(struct inode *inode,  void *data)
88 {
89 	struct v9fs_inode *v9inode = V9FS_I(inode);
90 	struct p9_stat_dotl *st = (struct p9_stat_dotl *)data;
91 
92 	memcpy(&v9inode->qid, &st->qid, sizeof(st->qid));
93 	inode->i_generation = st->st_gen;
94 	return 0;
95 }
96 
97 static struct inode *v9fs_qid_iget_dotl(struct super_block *sb,
98 					struct p9_qid *qid,
99 					struct p9_fid *fid,
100 					struct p9_stat_dotl *st,
101 					int new)
102 {
103 	int retval;
104 	unsigned long i_ino;
105 	struct inode *inode;
106 	struct v9fs_session_info *v9ses = sb->s_fs_info;
107 	int (*test)(struct inode *inode, void *data);
108 
109 	if (new)
110 		test = v9fs_test_new_inode_dotl;
111 	else
112 		test = v9fs_test_inode_dotl;
113 
114 	i_ino = v9fs_qid2ino(qid);
115 	inode = iget5_locked(sb, i_ino, test, v9fs_set_inode_dotl, st);
116 	if (!inode)
117 		return ERR_PTR(-ENOMEM);
118 	if (!(inode->i_state & I_NEW))
119 		return inode;
120 	/*
121 	 * initialize the inode with the stat info
122 	 * FIXME!! we may need support for stale inodes
123 	 * later.
124 	 */
125 	inode->i_ino = i_ino;
126 	retval = v9fs_init_inode(v9ses, inode,
127 				 st->st_mode, new_decode_dev(st->st_rdev));
128 	if (retval)
129 		goto error;
130 
131 	v9fs_stat2inode_dotl(st, inode, 0);
132 	v9fs_cache_inode_get_cookie(inode);
133 	retval = v9fs_get_acl(inode, fid);
134 	if (retval)
135 		goto error;
136 
137 	unlock_new_inode(inode);
138 	return inode;
139 error:
140 	iget_failed(inode);
141 	return ERR_PTR(retval);
142 
143 }
144 
145 struct inode *
146 v9fs_inode_from_fid_dotl(struct v9fs_session_info *v9ses, struct p9_fid *fid,
147 			 struct super_block *sb, int new)
148 {
149 	struct p9_stat_dotl *st;
150 	struct inode *inode = NULL;
151 
152 	st = p9_client_getattr_dotl(fid, P9_STATS_BASIC | P9_STATS_GEN);
153 	if (IS_ERR(st))
154 		return ERR_CAST(st);
155 
156 	inode = v9fs_qid_iget_dotl(sb, &st->qid, fid, st, new);
157 	kfree(st);
158 	return inode;
159 }
160 
161 struct dotl_openflag_map {
162 	int open_flag;
163 	int dotl_flag;
164 };
165 
166 static int v9fs_mapped_dotl_flags(int flags)
167 {
168 	int i;
169 	int rflags = 0;
170 	struct dotl_openflag_map dotl_oflag_map[] = {
171 		{ O_CREAT,	P9_DOTL_CREATE },
172 		{ O_EXCL,	P9_DOTL_EXCL },
173 		{ O_NOCTTY,	P9_DOTL_NOCTTY },
174 		{ O_APPEND,	P9_DOTL_APPEND },
175 		{ O_NONBLOCK,	P9_DOTL_NONBLOCK },
176 		{ O_DSYNC,	P9_DOTL_DSYNC },
177 		{ FASYNC,	P9_DOTL_FASYNC },
178 		{ O_DIRECT,	P9_DOTL_DIRECT },
179 		{ O_LARGEFILE,	P9_DOTL_LARGEFILE },
180 		{ O_DIRECTORY,	P9_DOTL_DIRECTORY },
181 		{ O_NOFOLLOW,	P9_DOTL_NOFOLLOW },
182 		{ O_NOATIME,	P9_DOTL_NOATIME },
183 		{ O_CLOEXEC,	P9_DOTL_CLOEXEC },
184 		{ O_SYNC,	P9_DOTL_SYNC},
185 	};
186 	for (i = 0; i < ARRAY_SIZE(dotl_oflag_map); i++) {
187 		if (flags & dotl_oflag_map[i].open_flag)
188 			rflags |= dotl_oflag_map[i].dotl_flag;
189 	}
190 	return rflags;
191 }
192 
193 /**
194  * v9fs_open_to_dotl_flags- convert Linux specific open flags to
195  * plan 9 open flag.
196  * @flags: flags to convert
197  */
198 int v9fs_open_to_dotl_flags(int flags)
199 {
200 	int rflags = 0;
201 
202 	/*
203 	 * We have same bits for P9_DOTL_READONLY, P9_DOTL_WRONLY
204 	 * and P9_DOTL_NOACCESS
205 	 */
206 	rflags |= flags & O_ACCMODE;
207 	rflags |= v9fs_mapped_dotl_flags(flags);
208 
209 	return rflags;
210 }
211 
212 /**
213  * v9fs_vfs_create_dotl - VFS hook to create files for 9P2000.L protocol.
214  * @mnt_userns: The user namespace of the mount
215  * @dir: directory inode that is being created
216  * @dentry:  dentry that is being deleted
217  * @omode: create permissions
218  * @excl: True if the file must not yet exist
219  *
220  */
221 static int
222 v9fs_vfs_create_dotl(struct user_namespace *mnt_userns, struct inode *dir,
223 		     struct dentry *dentry, umode_t omode, bool excl)
224 {
225 	return v9fs_vfs_mknod_dotl(mnt_userns, dir, dentry, omode, 0);
226 }
227 
228 static int
229 v9fs_vfs_atomic_open_dotl(struct inode *dir, struct dentry *dentry,
230 			  struct file *file, unsigned int flags, umode_t omode)
231 {
232 	int err = 0;
233 	kgid_t gid;
234 	umode_t mode;
235 	const unsigned char *name = NULL;
236 	struct p9_qid qid;
237 	struct inode *inode;
238 	struct p9_fid *fid = NULL;
239 	struct v9fs_inode *v9inode;
240 	struct p9_fid *dfid = NULL, *ofid = NULL, *inode_fid = NULL;
241 	struct v9fs_session_info *v9ses;
242 	struct posix_acl *pacl = NULL, *dacl = NULL;
243 	struct dentry *res = NULL;
244 
245 	if (d_in_lookup(dentry)) {
246 		res = v9fs_vfs_lookup(dir, dentry, 0);
247 		if (IS_ERR(res))
248 			return PTR_ERR(res);
249 
250 		if (res)
251 			dentry = res;
252 	}
253 
254 	/* Only creates */
255 	if (!(flags & O_CREAT) || d_really_is_positive(dentry))
256 		return	finish_no_open(file, res);
257 
258 	v9ses = v9fs_inode2v9ses(dir);
259 
260 	name = dentry->d_name.name;
261 	p9_debug(P9_DEBUG_VFS, "name:%s flags:0x%x mode:0x%x\n",
262 		 name, flags, omode);
263 
264 	dfid = v9fs_parent_fid(dentry);
265 	if (IS_ERR(dfid)) {
266 		err = PTR_ERR(dfid);
267 		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
268 		goto out;
269 	}
270 
271 	/* clone a fid to use for creation */
272 	ofid = clone_fid(dfid);
273 	if (IS_ERR(ofid)) {
274 		err = PTR_ERR(ofid);
275 		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
276 		goto out;
277 	}
278 
279 	gid = v9fs_get_fsgid_for_create(dir);
280 
281 	mode = omode;
282 	/* Update mode based on ACL value */
283 	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
284 	if (err) {
285 		p9_debug(P9_DEBUG_VFS, "Failed to get acl values in creat %d\n",
286 			 err);
287 		goto out;
288 	}
289 	err = p9_client_create_dotl(ofid, name, v9fs_open_to_dotl_flags(flags),
290 				    mode, gid, &qid);
291 	if (err < 0) {
292 		p9_debug(P9_DEBUG_VFS, "p9_client_open_dotl failed in creat %d\n",
293 			 err);
294 		goto out;
295 	}
296 	v9fs_invalidate_inode_attr(dir);
297 
298 	/* instantiate inode and assign the unopened fid to the dentry */
299 	fid = p9_client_walk(dfid, 1, &name, 1);
300 	if (IS_ERR(fid)) {
301 		err = PTR_ERR(fid);
302 		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
303 		goto out;
304 	}
305 	inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
306 	if (IS_ERR(inode)) {
307 		err = PTR_ERR(inode);
308 		p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n", err);
309 		goto out;
310 	}
311 	/* Now set the ACL based on the default value */
312 	v9fs_set_create_acl(inode, fid, dacl, pacl);
313 
314 	v9fs_fid_add(dentry, &fid);
315 	d_instantiate(dentry, inode);
316 
317 	v9inode = V9FS_I(inode);
318 	mutex_lock(&v9inode->v_mutex);
319 	if ((v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) &&
320 	    !v9inode->writeback_fid &&
321 	    ((flags & O_ACCMODE) != O_RDONLY)) {
322 		/*
323 		 * clone a fid and add it to writeback_fid
324 		 * we do it during open time instead of
325 		 * page dirty time via write_begin/page_mkwrite
326 		 * because we want write after unlink usecase
327 		 * to work.
328 		 */
329 		inode_fid = v9fs_writeback_fid(dentry);
330 		if (IS_ERR(inode_fid)) {
331 			err = PTR_ERR(inode_fid);
332 			mutex_unlock(&v9inode->v_mutex);
333 			goto out;
334 		}
335 		v9inode->writeback_fid = (void *) inode_fid;
336 	}
337 	mutex_unlock(&v9inode->v_mutex);
338 	/* Since we are opening a file, assign the open fid to the file */
339 	err = finish_open(file, dentry, generic_file_open);
340 	if (err)
341 		goto out;
342 	file->private_data = ofid;
343 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
344 		fscache_use_cookie(v9fs_inode_cookie(v9inode),
345 				   file->f_mode & FMODE_WRITE);
346 	v9fs_open_fid_add(inode, &ofid);
347 	file->f_mode |= FMODE_CREATED;
348 out:
349 	p9_fid_put(dfid);
350 	p9_fid_put(ofid);
351 	p9_fid_put(fid);
352 	v9fs_put_acl(dacl, pacl);
353 	dput(res);
354 	return err;
355 }
356 
357 /**
358  * v9fs_vfs_mkdir_dotl - VFS mkdir hook to create a directory
359  * @mnt_userns: The user namespace of the mount
360  * @dir:  inode that is being unlinked
361  * @dentry: dentry that is being unlinked
362  * @omode: mode for new directory
363  *
364  */
365 
366 static int v9fs_vfs_mkdir_dotl(struct user_namespace *mnt_userns,
367 			       struct inode *dir, struct dentry *dentry,
368 			       umode_t omode)
369 {
370 	int err;
371 	struct v9fs_session_info *v9ses;
372 	struct p9_fid *fid = NULL, *dfid = NULL;
373 	kgid_t gid;
374 	const unsigned char *name;
375 	umode_t mode;
376 	struct inode *inode;
377 	struct p9_qid qid;
378 	struct posix_acl *dacl = NULL, *pacl = NULL;
379 
380 	p9_debug(P9_DEBUG_VFS, "name %pd\n", dentry);
381 	err = 0;
382 	v9ses = v9fs_inode2v9ses(dir);
383 
384 	omode |= S_IFDIR;
385 	if (dir->i_mode & S_ISGID)
386 		omode |= S_ISGID;
387 
388 	dfid = v9fs_parent_fid(dentry);
389 	if (IS_ERR(dfid)) {
390 		err = PTR_ERR(dfid);
391 		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
392 		goto error;
393 	}
394 
395 	gid = v9fs_get_fsgid_for_create(dir);
396 	mode = omode;
397 	/* Update mode based on ACL value */
398 	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
399 	if (err) {
400 		p9_debug(P9_DEBUG_VFS, "Failed to get acl values in mkdir %d\n",
401 			 err);
402 		goto error;
403 	}
404 	name = dentry->d_name.name;
405 	err = p9_client_mkdir_dotl(dfid, name, mode, gid, &qid);
406 	if (err < 0)
407 		goto error;
408 	fid = p9_client_walk(dfid, 1, &name, 1);
409 	if (IS_ERR(fid)) {
410 		err = PTR_ERR(fid);
411 		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
412 			 err);
413 		goto error;
414 	}
415 
416 	/* instantiate inode and assign the unopened fid to the dentry */
417 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
418 		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
419 		if (IS_ERR(inode)) {
420 			err = PTR_ERR(inode);
421 			p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n",
422 				 err);
423 			goto error;
424 		}
425 		v9fs_fid_add(dentry, &fid);
426 		v9fs_set_create_acl(inode, fid, dacl, pacl);
427 		d_instantiate(dentry, inode);
428 		err = 0;
429 	} else {
430 		/*
431 		 * Not in cached mode. No need to populate
432 		 * inode with stat. We need to get an inode
433 		 * so that we can set the acl with dentry
434 		 */
435 		inode = v9fs_get_inode(dir->i_sb, mode, 0);
436 		if (IS_ERR(inode)) {
437 			err = PTR_ERR(inode);
438 			goto error;
439 		}
440 		v9fs_set_create_acl(inode, fid, dacl, pacl);
441 		d_instantiate(dentry, inode);
442 	}
443 	inc_nlink(dir);
444 	v9fs_invalidate_inode_attr(dir);
445 error:
446 	p9_fid_put(fid);
447 	v9fs_put_acl(dacl, pacl);
448 	p9_fid_put(dfid);
449 	return err;
450 }
451 
452 static int
453 v9fs_vfs_getattr_dotl(struct user_namespace *mnt_userns,
454 		      const struct path *path, struct kstat *stat,
455 		      u32 request_mask, unsigned int flags)
456 {
457 	struct dentry *dentry = path->dentry;
458 	struct v9fs_session_info *v9ses;
459 	struct p9_fid *fid;
460 	struct p9_stat_dotl *st;
461 
462 	p9_debug(P9_DEBUG_VFS, "dentry: %p\n", dentry);
463 	v9ses = v9fs_dentry2v9ses(dentry);
464 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
465 		generic_fillattr(&init_user_ns, d_inode(dentry), stat);
466 		return 0;
467 	}
468 	fid = v9fs_fid_lookup(dentry);
469 	if (IS_ERR(fid))
470 		return PTR_ERR(fid);
471 
472 	/* Ask for all the fields in stat structure. Server will return
473 	 * whatever it supports
474 	 */
475 
476 	st = p9_client_getattr_dotl(fid, P9_STATS_ALL);
477 	p9_fid_put(fid);
478 	if (IS_ERR(st))
479 		return PTR_ERR(st);
480 
481 	v9fs_stat2inode_dotl(st, d_inode(dentry), 0);
482 	generic_fillattr(&init_user_ns, d_inode(dentry), stat);
483 	/* Change block size to what the server returned */
484 	stat->blksize = st->st_blksize;
485 
486 	kfree(st);
487 	return 0;
488 }
489 
490 /*
491  * Attribute flags.
492  */
493 #define P9_ATTR_MODE		(1 << 0)
494 #define P9_ATTR_UID		(1 << 1)
495 #define P9_ATTR_GID		(1 << 2)
496 #define P9_ATTR_SIZE		(1 << 3)
497 #define P9_ATTR_ATIME		(1 << 4)
498 #define P9_ATTR_MTIME		(1 << 5)
499 #define P9_ATTR_CTIME		(1 << 6)
500 #define P9_ATTR_ATIME_SET	(1 << 7)
501 #define P9_ATTR_MTIME_SET	(1 << 8)
502 
503 struct dotl_iattr_map {
504 	int iattr_valid;
505 	int p9_iattr_valid;
506 };
507 
508 static int v9fs_mapped_iattr_valid(int iattr_valid)
509 {
510 	int i;
511 	int p9_iattr_valid = 0;
512 	struct dotl_iattr_map dotl_iattr_map[] = {
513 		{ ATTR_MODE,		P9_ATTR_MODE },
514 		{ ATTR_UID,		P9_ATTR_UID },
515 		{ ATTR_GID,		P9_ATTR_GID },
516 		{ ATTR_SIZE,		P9_ATTR_SIZE },
517 		{ ATTR_ATIME,		P9_ATTR_ATIME },
518 		{ ATTR_MTIME,		P9_ATTR_MTIME },
519 		{ ATTR_CTIME,		P9_ATTR_CTIME },
520 		{ ATTR_ATIME_SET,	P9_ATTR_ATIME_SET },
521 		{ ATTR_MTIME_SET,	P9_ATTR_MTIME_SET },
522 	};
523 	for (i = 0; i < ARRAY_SIZE(dotl_iattr_map); i++) {
524 		if (iattr_valid & dotl_iattr_map[i].iattr_valid)
525 			p9_iattr_valid |= dotl_iattr_map[i].p9_iattr_valid;
526 	}
527 	return p9_iattr_valid;
528 }
529 
530 /**
531  * v9fs_vfs_setattr_dotl - set file metadata
532  * @mnt_userns: The user namespace of the mount
533  * @dentry: file whose metadata to set
534  * @iattr: metadata assignment structure
535  *
536  */
537 
538 int v9fs_vfs_setattr_dotl(struct user_namespace *mnt_userns,
539 			  struct dentry *dentry, struct iattr *iattr)
540 {
541 	int retval, use_dentry = 0;
542 	struct p9_fid *fid = NULL;
543 	struct p9_iattr_dotl p9attr = {
544 		.uid = INVALID_UID,
545 		.gid = INVALID_GID,
546 	};
547 	struct inode *inode = d_inode(dentry);
548 
549 	p9_debug(P9_DEBUG_VFS, "\n");
550 
551 	retval = setattr_prepare(&init_user_ns, dentry, iattr);
552 	if (retval)
553 		return retval;
554 
555 	p9attr.valid = v9fs_mapped_iattr_valid(iattr->ia_valid);
556 	if (iattr->ia_valid & ATTR_MODE)
557 		p9attr.mode = iattr->ia_mode;
558 	if (iattr->ia_valid & ATTR_UID)
559 		p9attr.uid = iattr->ia_uid;
560 	if (iattr->ia_valid & ATTR_GID)
561 		p9attr.gid = iattr->ia_gid;
562 	if (iattr->ia_valid & ATTR_SIZE)
563 		p9attr.size = iattr->ia_size;
564 	if (iattr->ia_valid & ATTR_ATIME_SET) {
565 		p9attr.atime_sec = iattr->ia_atime.tv_sec;
566 		p9attr.atime_nsec = iattr->ia_atime.tv_nsec;
567 	}
568 	if (iattr->ia_valid & ATTR_MTIME_SET) {
569 		p9attr.mtime_sec = iattr->ia_mtime.tv_sec;
570 		p9attr.mtime_nsec = iattr->ia_mtime.tv_nsec;
571 	}
572 
573 	if (iattr->ia_valid & ATTR_FILE) {
574 		fid = iattr->ia_file->private_data;
575 		WARN_ON(!fid);
576 	}
577 	if (!fid) {
578 		fid = v9fs_fid_lookup(dentry);
579 		use_dentry = 1;
580 	}
581 	if (IS_ERR(fid))
582 		return PTR_ERR(fid);
583 
584 	/* Write all dirty data */
585 	if (S_ISREG(inode->i_mode))
586 		filemap_write_and_wait(inode->i_mapping);
587 
588 	retval = p9_client_setattr(fid, &p9attr);
589 	if (retval < 0) {
590 		if (use_dentry)
591 			p9_fid_put(fid);
592 		return retval;
593 	}
594 
595 	if ((iattr->ia_valid & ATTR_SIZE) &&
596 	    iattr->ia_size != i_size_read(inode))
597 		truncate_setsize(inode, iattr->ia_size);
598 
599 	v9fs_invalidate_inode_attr(inode);
600 	setattr_copy(&init_user_ns, inode, iattr);
601 	mark_inode_dirty(inode);
602 	if (iattr->ia_valid & ATTR_MODE) {
603 		/* We also want to update ACL when we update mode bits */
604 		retval = v9fs_acl_chmod(inode, fid);
605 		if (retval < 0) {
606 			if (use_dentry)
607 				p9_fid_put(fid);
608 			return retval;
609 		}
610 	}
611 	if (use_dentry)
612 		p9_fid_put(fid);
613 
614 	return 0;
615 }
616 
617 /**
618  * v9fs_stat2inode_dotl - populate an inode structure with stat info
619  * @stat: stat structure
620  * @inode: inode to populate
621  * @flags: ctrl flags (e.g. V9FS_STAT2INODE_KEEP_ISIZE)
622  *
623  */
624 
625 void
626 v9fs_stat2inode_dotl(struct p9_stat_dotl *stat, struct inode *inode,
627 		      unsigned int flags)
628 {
629 	umode_t mode;
630 	struct v9fs_inode *v9inode = V9FS_I(inode);
631 
632 	if ((stat->st_result_mask & P9_STATS_BASIC) == P9_STATS_BASIC) {
633 		inode->i_atime.tv_sec = stat->st_atime_sec;
634 		inode->i_atime.tv_nsec = stat->st_atime_nsec;
635 		inode->i_mtime.tv_sec = stat->st_mtime_sec;
636 		inode->i_mtime.tv_nsec = stat->st_mtime_nsec;
637 		inode->i_ctime.tv_sec = stat->st_ctime_sec;
638 		inode->i_ctime.tv_nsec = stat->st_ctime_nsec;
639 		inode->i_uid = stat->st_uid;
640 		inode->i_gid = stat->st_gid;
641 		set_nlink(inode, stat->st_nlink);
642 
643 		mode = stat->st_mode & S_IALLUGO;
644 		mode |= inode->i_mode & ~S_IALLUGO;
645 		inode->i_mode = mode;
646 
647 		if (!(flags & V9FS_STAT2INODE_KEEP_ISIZE))
648 			v9fs_i_size_write(inode, stat->st_size);
649 		inode->i_blocks = stat->st_blocks;
650 	} else {
651 		if (stat->st_result_mask & P9_STATS_ATIME) {
652 			inode->i_atime.tv_sec = stat->st_atime_sec;
653 			inode->i_atime.tv_nsec = stat->st_atime_nsec;
654 		}
655 		if (stat->st_result_mask & P9_STATS_MTIME) {
656 			inode->i_mtime.tv_sec = stat->st_mtime_sec;
657 			inode->i_mtime.tv_nsec = stat->st_mtime_nsec;
658 		}
659 		if (stat->st_result_mask & P9_STATS_CTIME) {
660 			inode->i_ctime.tv_sec = stat->st_ctime_sec;
661 			inode->i_ctime.tv_nsec = stat->st_ctime_nsec;
662 		}
663 		if (stat->st_result_mask & P9_STATS_UID)
664 			inode->i_uid = stat->st_uid;
665 		if (stat->st_result_mask & P9_STATS_GID)
666 			inode->i_gid = stat->st_gid;
667 		if (stat->st_result_mask & P9_STATS_NLINK)
668 			set_nlink(inode, stat->st_nlink);
669 		if (stat->st_result_mask & P9_STATS_MODE) {
670 			mode = stat->st_mode & S_IALLUGO;
671 			mode |= inode->i_mode & ~S_IALLUGO;
672 			inode->i_mode = mode;
673 		}
674 		if (!(flags & V9FS_STAT2INODE_KEEP_ISIZE) &&
675 		    stat->st_result_mask & P9_STATS_SIZE)
676 			v9fs_i_size_write(inode, stat->st_size);
677 		if (stat->st_result_mask & P9_STATS_BLOCKS)
678 			inode->i_blocks = stat->st_blocks;
679 	}
680 	if (stat->st_result_mask & P9_STATS_GEN)
681 		inode->i_generation = stat->st_gen;
682 
683 	/* Currently we don't support P9_STATS_BTIME and P9_STATS_DATA_VERSION
684 	 * because the inode structure does not have fields for them.
685 	 */
686 	v9inode->cache_validity &= ~V9FS_INO_INVALID_ATTR;
687 }
688 
689 static int
690 v9fs_vfs_symlink_dotl(struct user_namespace *mnt_userns, struct inode *dir,
691 		      struct dentry *dentry, const char *symname)
692 {
693 	int err;
694 	kgid_t gid;
695 	const unsigned char *name;
696 	struct p9_qid qid;
697 	struct inode *inode;
698 	struct p9_fid *dfid;
699 	struct p9_fid *fid = NULL;
700 	struct v9fs_session_info *v9ses;
701 
702 	name = dentry->d_name.name;
703 	p9_debug(P9_DEBUG_VFS, "%lu,%s,%s\n", dir->i_ino, name, symname);
704 	v9ses = v9fs_inode2v9ses(dir);
705 
706 	dfid = v9fs_parent_fid(dentry);
707 	if (IS_ERR(dfid)) {
708 		err = PTR_ERR(dfid);
709 		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
710 		return err;
711 	}
712 
713 	gid = v9fs_get_fsgid_for_create(dir);
714 
715 	/* Server doesn't alter fid on TSYMLINK. Hence no need to clone it. */
716 	err = p9_client_symlink(dfid, name, symname, gid, &qid);
717 
718 	if (err < 0) {
719 		p9_debug(P9_DEBUG_VFS, "p9_client_symlink failed %d\n", err);
720 		goto error;
721 	}
722 
723 	v9fs_invalidate_inode_attr(dir);
724 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
725 		/* Now walk from the parent so we can get an unopened fid. */
726 		fid = p9_client_walk(dfid, 1, &name, 1);
727 		if (IS_ERR(fid)) {
728 			err = PTR_ERR(fid);
729 			p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
730 				 err);
731 			goto error;
732 		}
733 
734 		/* instantiate inode and assign the unopened fid to dentry */
735 		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
736 		if (IS_ERR(inode)) {
737 			err = PTR_ERR(inode);
738 			p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n",
739 				 err);
740 			goto error;
741 		}
742 		v9fs_fid_add(dentry, &fid);
743 		d_instantiate(dentry, inode);
744 		err = 0;
745 	} else {
746 		/* Not in cached mode. No need to populate inode with stat */
747 		inode = v9fs_get_inode(dir->i_sb, S_IFLNK, 0);
748 		if (IS_ERR(inode)) {
749 			err = PTR_ERR(inode);
750 			goto error;
751 		}
752 		d_instantiate(dentry, inode);
753 	}
754 
755 error:
756 	p9_fid_put(fid);
757 	p9_fid_put(dfid);
758 	return err;
759 }
760 
761 /**
762  * v9fs_vfs_link_dotl - create a hardlink for dotl
763  * @old_dentry: dentry for file to link to
764  * @dir: inode destination for new link
765  * @dentry: dentry for link
766  *
767  */
768 
769 static int
770 v9fs_vfs_link_dotl(struct dentry *old_dentry, struct inode *dir,
771 		struct dentry *dentry)
772 {
773 	int err;
774 	struct p9_fid *dfid, *oldfid;
775 	struct v9fs_session_info *v9ses;
776 
777 	p9_debug(P9_DEBUG_VFS, "dir ino: %lu, old_name: %pd, new_name: %pd\n",
778 		 dir->i_ino, old_dentry, dentry);
779 
780 	v9ses = v9fs_inode2v9ses(dir);
781 	dfid = v9fs_parent_fid(dentry);
782 	if (IS_ERR(dfid))
783 		return PTR_ERR(dfid);
784 
785 	oldfid = v9fs_fid_lookup(old_dentry);
786 	if (IS_ERR(oldfid)) {
787 		p9_fid_put(dfid);
788 		return PTR_ERR(oldfid);
789 	}
790 
791 	err = p9_client_link(dfid, oldfid, dentry->d_name.name);
792 
793 	p9_fid_put(dfid);
794 	p9_fid_put(oldfid);
795 	if (err < 0) {
796 		p9_debug(P9_DEBUG_VFS, "p9_client_link failed %d\n", err);
797 		return err;
798 	}
799 
800 	v9fs_invalidate_inode_attr(dir);
801 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
802 		/* Get the latest stat info from server. */
803 		struct p9_fid *fid;
804 
805 		fid = v9fs_fid_lookup(old_dentry);
806 		if (IS_ERR(fid))
807 			return PTR_ERR(fid);
808 
809 		v9fs_refresh_inode_dotl(fid, d_inode(old_dentry));
810 		p9_fid_put(fid);
811 	}
812 	ihold(d_inode(old_dentry));
813 	d_instantiate(dentry, d_inode(old_dentry));
814 
815 	return err;
816 }
817 
818 /**
819  * v9fs_vfs_mknod_dotl - create a special file
820  * @mnt_userns: The user namespace of the mount
821  * @dir: inode destination for new link
822  * @dentry: dentry for file
823  * @omode: mode for creation
824  * @rdev: device associated with special file
825  *
826  */
827 static int
828 v9fs_vfs_mknod_dotl(struct user_namespace *mnt_userns, struct inode *dir,
829 		    struct dentry *dentry, umode_t omode, dev_t rdev)
830 {
831 	int err;
832 	kgid_t gid;
833 	const unsigned char *name;
834 	umode_t mode;
835 	struct v9fs_session_info *v9ses;
836 	struct p9_fid *fid = NULL, *dfid = NULL;
837 	struct inode *inode;
838 	struct p9_qid qid;
839 	struct posix_acl *dacl = NULL, *pacl = NULL;
840 
841 	p9_debug(P9_DEBUG_VFS, " %lu,%pd mode: %x MAJOR: %u MINOR: %u\n",
842 		 dir->i_ino, dentry, omode,
843 		 MAJOR(rdev), MINOR(rdev));
844 
845 	v9ses = v9fs_inode2v9ses(dir);
846 	dfid = v9fs_parent_fid(dentry);
847 	if (IS_ERR(dfid)) {
848 		err = PTR_ERR(dfid);
849 		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
850 		goto error;
851 	}
852 
853 	gid = v9fs_get_fsgid_for_create(dir);
854 	mode = omode;
855 	/* Update mode based on ACL value */
856 	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
857 	if (err) {
858 		p9_debug(P9_DEBUG_VFS, "Failed to get acl values in mknod %d\n",
859 			 err);
860 		goto error;
861 	}
862 	name = dentry->d_name.name;
863 
864 	err = p9_client_mknod_dotl(dfid, name, mode, rdev, gid, &qid);
865 	if (err < 0)
866 		goto error;
867 
868 	v9fs_invalidate_inode_attr(dir);
869 	fid = p9_client_walk(dfid, 1, &name, 1);
870 	if (IS_ERR(fid)) {
871 		err = PTR_ERR(fid);
872 		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
873 			 err);
874 		goto error;
875 	}
876 
877 	/* instantiate inode and assign the unopened fid to the dentry */
878 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
879 		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
880 		if (IS_ERR(inode)) {
881 			err = PTR_ERR(inode);
882 			p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n",
883 				 err);
884 			goto error;
885 		}
886 		v9fs_set_create_acl(inode, fid, dacl, pacl);
887 		v9fs_fid_add(dentry, &fid);
888 		d_instantiate(dentry, inode);
889 		err = 0;
890 	} else {
891 		/*
892 		 * Not in cached mode. No need to populate inode with stat.
893 		 * socket syscall returns a fd, so we need instantiate
894 		 */
895 		inode = v9fs_get_inode(dir->i_sb, mode, rdev);
896 		if (IS_ERR(inode)) {
897 			err = PTR_ERR(inode);
898 			goto error;
899 		}
900 		v9fs_set_create_acl(inode, fid, dacl, pacl);
901 		d_instantiate(dentry, inode);
902 	}
903 error:
904 	p9_fid_put(fid);
905 	v9fs_put_acl(dacl, pacl);
906 	p9_fid_put(dfid);
907 
908 	return err;
909 }
910 
911 /**
912  * v9fs_vfs_get_link_dotl - follow a symlink path
913  * @dentry: dentry for symlink
914  * @inode: inode for symlink
915  * @done: destructor for return value
916  */
917 
918 static const char *
919 v9fs_vfs_get_link_dotl(struct dentry *dentry,
920 		       struct inode *inode,
921 		       struct delayed_call *done)
922 {
923 	struct p9_fid *fid;
924 	char *target;
925 	int retval;
926 
927 	if (!dentry)
928 		return ERR_PTR(-ECHILD);
929 
930 	p9_debug(P9_DEBUG_VFS, "%pd\n", dentry);
931 
932 	fid = v9fs_fid_lookup(dentry);
933 	if (IS_ERR(fid))
934 		return ERR_CAST(fid);
935 	retval = p9_client_readlink(fid, &target);
936 	p9_fid_put(fid);
937 	if (retval)
938 		return ERR_PTR(retval);
939 	set_delayed_call(done, kfree_link, target);
940 	return target;
941 }
942 
943 int v9fs_refresh_inode_dotl(struct p9_fid *fid, struct inode *inode)
944 {
945 	struct p9_stat_dotl *st;
946 	struct v9fs_session_info *v9ses;
947 	unsigned int flags;
948 
949 	v9ses = v9fs_inode2v9ses(inode);
950 	st = p9_client_getattr_dotl(fid, P9_STATS_ALL);
951 	if (IS_ERR(st))
952 		return PTR_ERR(st);
953 	/*
954 	 * Don't update inode if the file type is different
955 	 */
956 	if (inode_wrong_type(inode, st->st_mode))
957 		goto out;
958 
959 	/*
960 	 * We don't want to refresh inode->i_size,
961 	 * because we may have cached data
962 	 */
963 	flags = (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) ?
964 		V9FS_STAT2INODE_KEEP_ISIZE : 0;
965 	v9fs_stat2inode_dotl(st, inode, flags);
966 out:
967 	kfree(st);
968 	return 0;
969 }
970 
971 const struct inode_operations v9fs_dir_inode_operations_dotl = {
972 	.create = v9fs_vfs_create_dotl,
973 	.atomic_open = v9fs_vfs_atomic_open_dotl,
974 	.lookup = v9fs_vfs_lookup,
975 	.link = v9fs_vfs_link_dotl,
976 	.symlink = v9fs_vfs_symlink_dotl,
977 	.unlink = v9fs_vfs_unlink,
978 	.mkdir = v9fs_vfs_mkdir_dotl,
979 	.rmdir = v9fs_vfs_rmdir,
980 	.mknod = v9fs_vfs_mknod_dotl,
981 	.rename = v9fs_vfs_rename,
982 	.getattr = v9fs_vfs_getattr_dotl,
983 	.setattr = v9fs_vfs_setattr_dotl,
984 	.listxattr = v9fs_listxattr,
985 	.get_inode_acl = v9fs_iop_get_inode_acl,
986 	.get_acl = v9fs_iop_get_acl,
987 	.set_acl = v9fs_iop_set_acl,
988 };
989 
990 const struct inode_operations v9fs_file_inode_operations_dotl = {
991 	.getattr = v9fs_vfs_getattr_dotl,
992 	.setattr = v9fs_vfs_setattr_dotl,
993 	.listxattr = v9fs_listxattr,
994 	.get_inode_acl = v9fs_iop_get_inode_acl,
995 	.get_acl = v9fs_iop_get_acl,
996 	.set_acl = v9fs_iop_set_acl,
997 };
998 
999 const struct inode_operations v9fs_symlink_inode_operations_dotl = {
1000 	.get_link = v9fs_vfs_get_link_dotl,
1001 	.getattr = v9fs_vfs_getattr_dotl,
1002 	.setattr = v9fs_vfs_setattr_dotl,
1003 	.listxattr = v9fs_listxattr,
1004 };
1005