xref: /openbmc/linux/fs/9p/vfs_inode_dotl.c (revision e40573a4)
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 = NULL, *ofid = NULL, *inode_fid = NULL;
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 		goto out;
278 	}
279 
280 	gid = v9fs_get_fsgid_for_create(dir);
281 
282 	mode = omode;
283 	/* Update mode based on ACL value */
284 	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
285 	if (err) {
286 		p9_debug(P9_DEBUG_VFS, "Failed to get acl values in creat %d\n",
287 			 err);
288 		goto out;
289 	}
290 	err = p9_client_create_dotl(ofid, name, v9fs_open_to_dotl_flags(flags),
291 				    mode, gid, &qid);
292 	if (err < 0) {
293 		p9_debug(P9_DEBUG_VFS, "p9_client_open_dotl failed in creat %d\n",
294 			 err);
295 		goto out;
296 	}
297 	v9fs_invalidate_inode_attr(dir);
298 
299 	/* instantiate inode and assign the unopened fid to the dentry */
300 	fid = p9_client_walk(dfid, 1, &name, 1);
301 	if (IS_ERR(fid)) {
302 		err = PTR_ERR(fid);
303 		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
304 		goto out;
305 	}
306 	inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
307 	if (IS_ERR(inode)) {
308 		err = PTR_ERR(inode);
309 		p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n", err);
310 		goto out;
311 	}
312 	/* Now set the ACL based on the default value */
313 	v9fs_set_create_acl(inode, fid, dacl, pacl);
314 
315 	v9fs_fid_add(dentry, &fid);
316 	d_instantiate(dentry, inode);
317 
318 	v9inode = V9FS_I(inode);
319 	mutex_lock(&v9inode->v_mutex);
320 	if ((v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) &&
321 	    !v9inode->writeback_fid &&
322 	    ((flags & O_ACCMODE) != O_RDONLY)) {
323 		/*
324 		 * clone a fid and add it to writeback_fid
325 		 * we do it during open time instead of
326 		 * page dirty time via write_begin/page_mkwrite
327 		 * because we want write after unlink usecase
328 		 * to work.
329 		 */
330 		inode_fid = v9fs_writeback_fid(dentry);
331 		if (IS_ERR(inode_fid)) {
332 			err = PTR_ERR(inode_fid);
333 			mutex_unlock(&v9inode->v_mutex);
334 			goto out;
335 		}
336 		v9inode->writeback_fid = (void *) inode_fid;
337 	}
338 	mutex_unlock(&v9inode->v_mutex);
339 	/* Since we are opening a file, assign the open fid to the file */
340 	err = finish_open(file, dentry, generic_file_open);
341 	if (err)
342 		goto out;
343 	file->private_data = ofid;
344 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
345 		fscache_use_cookie(v9fs_inode_cookie(v9inode),
346 				   file->f_mode & FMODE_WRITE);
347 	v9fs_open_fid_add(inode, &ofid);
348 	file->f_mode |= FMODE_CREATED;
349 out:
350 	p9_fid_put(dfid);
351 	p9_fid_put(ofid);
352 	p9_fid_put(fid);
353 	v9fs_put_acl(dacl, pacl);
354 	dput(res);
355 	return err;
356 }
357 
358 /**
359  * v9fs_vfs_mkdir_dotl - VFS mkdir hook to create a directory
360  * @mnt_userns: The user namespace of the mount
361  * @dir:  inode that is being unlinked
362  * @dentry: dentry that is being unlinked
363  * @omode: mode for new directory
364  *
365  */
366 
367 static int v9fs_vfs_mkdir_dotl(struct user_namespace *mnt_userns,
368 			       struct inode *dir, struct dentry *dentry,
369 			       umode_t omode)
370 {
371 	int err;
372 	struct v9fs_session_info *v9ses;
373 	struct p9_fid *fid = NULL, *dfid = NULL;
374 	kgid_t gid;
375 	const unsigned char *name;
376 	umode_t mode;
377 	struct inode *inode;
378 	struct p9_qid qid;
379 	struct posix_acl *dacl = NULL, *pacl = NULL;
380 
381 	p9_debug(P9_DEBUG_VFS, "name %pd\n", dentry);
382 	err = 0;
383 	v9ses = v9fs_inode2v9ses(dir);
384 
385 	omode |= S_IFDIR;
386 	if (dir->i_mode & S_ISGID)
387 		omode |= S_ISGID;
388 
389 	dfid = v9fs_parent_fid(dentry);
390 	if (IS_ERR(dfid)) {
391 		err = PTR_ERR(dfid);
392 		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
393 		goto error;
394 	}
395 
396 	gid = v9fs_get_fsgid_for_create(dir);
397 	mode = omode;
398 	/* Update mode based on ACL value */
399 	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
400 	if (err) {
401 		p9_debug(P9_DEBUG_VFS, "Failed to get acl values in mkdir %d\n",
402 			 err);
403 		goto error;
404 	}
405 	name = dentry->d_name.name;
406 	err = p9_client_mkdir_dotl(dfid, name, mode, gid, &qid);
407 	if (err < 0)
408 		goto error;
409 	fid = p9_client_walk(dfid, 1, &name, 1);
410 	if (IS_ERR(fid)) {
411 		err = PTR_ERR(fid);
412 		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
413 			 err);
414 		goto error;
415 	}
416 
417 	/* instantiate inode and assign the unopened fid to the dentry */
418 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
419 		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
420 		if (IS_ERR(inode)) {
421 			err = PTR_ERR(inode);
422 			p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n",
423 				 err);
424 			goto error;
425 		}
426 		v9fs_fid_add(dentry, &fid);
427 		v9fs_set_create_acl(inode, fid, dacl, pacl);
428 		d_instantiate(dentry, inode);
429 		err = 0;
430 	} else {
431 		/*
432 		 * Not in cached mode. No need to populate
433 		 * inode with stat. We need to get an inode
434 		 * so that we can set the acl with dentry
435 		 */
436 		inode = v9fs_get_inode(dir->i_sb, mode, 0);
437 		if (IS_ERR(inode)) {
438 			err = PTR_ERR(inode);
439 			goto error;
440 		}
441 		v9fs_set_create_acl(inode, fid, dacl, pacl);
442 		d_instantiate(dentry, inode);
443 	}
444 	inc_nlink(dir);
445 	v9fs_invalidate_inode_attr(dir);
446 error:
447 	p9_fid_put(fid);
448 	v9fs_put_acl(dacl, pacl);
449 	p9_fid_put(dfid);
450 	return err;
451 }
452 
453 static int
454 v9fs_vfs_getattr_dotl(struct user_namespace *mnt_userns,
455 		      const struct path *path, struct kstat *stat,
456 		      u32 request_mask, unsigned int flags)
457 {
458 	struct dentry *dentry = path->dentry;
459 	struct v9fs_session_info *v9ses;
460 	struct p9_fid *fid;
461 	struct p9_stat_dotl *st;
462 
463 	p9_debug(P9_DEBUG_VFS, "dentry: %p\n", dentry);
464 	v9ses = v9fs_dentry2v9ses(dentry);
465 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
466 		generic_fillattr(&init_user_ns, d_inode(dentry), stat);
467 		return 0;
468 	}
469 	fid = v9fs_fid_lookup(dentry);
470 	if (IS_ERR(fid))
471 		return PTR_ERR(fid);
472 
473 	/* Ask for all the fields in stat structure. Server will return
474 	 * whatever it supports
475 	 */
476 
477 	st = p9_client_getattr_dotl(fid, P9_STATS_ALL);
478 	p9_fid_put(fid);
479 	if (IS_ERR(st))
480 		return PTR_ERR(st);
481 
482 	v9fs_stat2inode_dotl(st, d_inode(dentry), 0);
483 	generic_fillattr(&init_user_ns, d_inode(dentry), stat);
484 	/* Change block size to what the server returned */
485 	stat->blksize = st->st_blksize;
486 
487 	kfree(st);
488 	return 0;
489 }
490 
491 /*
492  * Attribute flags.
493  */
494 #define P9_ATTR_MODE		(1 << 0)
495 #define P9_ATTR_UID		(1 << 1)
496 #define P9_ATTR_GID		(1 << 2)
497 #define P9_ATTR_SIZE		(1 << 3)
498 #define P9_ATTR_ATIME		(1 << 4)
499 #define P9_ATTR_MTIME		(1 << 5)
500 #define P9_ATTR_CTIME		(1 << 6)
501 #define P9_ATTR_ATIME_SET	(1 << 7)
502 #define P9_ATTR_MTIME_SET	(1 << 8)
503 
504 struct dotl_iattr_map {
505 	int iattr_valid;
506 	int p9_iattr_valid;
507 };
508 
509 static int v9fs_mapped_iattr_valid(int iattr_valid)
510 {
511 	int i;
512 	int p9_iattr_valid = 0;
513 	struct dotl_iattr_map dotl_iattr_map[] = {
514 		{ ATTR_MODE,		P9_ATTR_MODE },
515 		{ ATTR_UID,		P9_ATTR_UID },
516 		{ ATTR_GID,		P9_ATTR_GID },
517 		{ ATTR_SIZE,		P9_ATTR_SIZE },
518 		{ ATTR_ATIME,		P9_ATTR_ATIME },
519 		{ ATTR_MTIME,		P9_ATTR_MTIME },
520 		{ ATTR_CTIME,		P9_ATTR_CTIME },
521 		{ ATTR_ATIME_SET,	P9_ATTR_ATIME_SET },
522 		{ ATTR_MTIME_SET,	P9_ATTR_MTIME_SET },
523 	};
524 	for (i = 0; i < ARRAY_SIZE(dotl_iattr_map); i++) {
525 		if (iattr_valid & dotl_iattr_map[i].iattr_valid)
526 			p9_iattr_valid |= dotl_iattr_map[i].p9_iattr_valid;
527 	}
528 	return p9_iattr_valid;
529 }
530 
531 /**
532  * v9fs_vfs_setattr_dotl - set file metadata
533  * @mnt_userns: The user namespace of the mount
534  * @dentry: file whose metadata to set
535  * @iattr: metadata assignment structure
536  *
537  */
538 
539 int v9fs_vfs_setattr_dotl(struct user_namespace *mnt_userns,
540 			  struct dentry *dentry, struct iattr *iattr)
541 {
542 	int retval, use_dentry = 0;
543 	struct p9_fid *fid = NULL;
544 	struct p9_iattr_dotl p9attr = {
545 		.uid = INVALID_UID,
546 		.gid = INVALID_GID,
547 	};
548 	struct inode *inode = d_inode(dentry);
549 
550 	p9_debug(P9_DEBUG_VFS, "\n");
551 
552 	retval = setattr_prepare(&init_user_ns, dentry, iattr);
553 	if (retval)
554 		return retval;
555 
556 	p9attr.valid = v9fs_mapped_iattr_valid(iattr->ia_valid);
557 	if (iattr->ia_valid & ATTR_MODE)
558 		p9attr.mode = iattr->ia_mode;
559 	if (iattr->ia_valid & ATTR_UID)
560 		p9attr.uid = iattr->ia_uid;
561 	if (iattr->ia_valid & ATTR_GID)
562 		p9attr.gid = iattr->ia_gid;
563 	if (iattr->ia_valid & ATTR_SIZE)
564 		p9attr.size = iattr->ia_size;
565 	if (iattr->ia_valid & ATTR_ATIME_SET) {
566 		p9attr.atime_sec = iattr->ia_atime.tv_sec;
567 		p9attr.atime_nsec = iattr->ia_atime.tv_nsec;
568 	}
569 	if (iattr->ia_valid & ATTR_MTIME_SET) {
570 		p9attr.mtime_sec = iattr->ia_mtime.tv_sec;
571 		p9attr.mtime_nsec = iattr->ia_mtime.tv_nsec;
572 	}
573 
574 	if (iattr->ia_valid & ATTR_FILE) {
575 		fid = iattr->ia_file->private_data;
576 		WARN_ON(!fid);
577 	}
578 	if (!fid) {
579 		fid = v9fs_fid_lookup(dentry);
580 		use_dentry = 1;
581 	}
582 	if (IS_ERR(fid))
583 		return PTR_ERR(fid);
584 
585 	/* Write all dirty data */
586 	if (S_ISREG(inode->i_mode))
587 		filemap_write_and_wait(inode->i_mapping);
588 
589 	retval = p9_client_setattr(fid, &p9attr);
590 	if (retval < 0) {
591 		if (use_dentry)
592 			p9_fid_put(fid);
593 		return retval;
594 	}
595 
596 	if ((iattr->ia_valid & ATTR_SIZE) &&
597 	    iattr->ia_size != i_size_read(inode))
598 		truncate_setsize(inode, iattr->ia_size);
599 
600 	v9fs_invalidate_inode_attr(inode);
601 	setattr_copy(&init_user_ns, inode, iattr);
602 	mark_inode_dirty(inode);
603 	if (iattr->ia_valid & ATTR_MODE) {
604 		/* We also want to update ACL when we update mode bits */
605 		retval = v9fs_acl_chmod(inode, fid);
606 		if (retval < 0) {
607 			if (use_dentry)
608 				p9_fid_put(fid);
609 			return retval;
610 		}
611 	}
612 	if (use_dentry)
613 		p9_fid_put(fid);
614 
615 	return 0;
616 }
617 
618 /**
619  * v9fs_stat2inode_dotl - populate an inode structure with stat info
620  * @stat: stat structure
621  * @inode: inode to populate
622  * @flags: ctrl flags (e.g. V9FS_STAT2INODE_KEEP_ISIZE)
623  *
624  */
625 
626 void
627 v9fs_stat2inode_dotl(struct p9_stat_dotl *stat, struct inode *inode,
628 		      unsigned int flags)
629 {
630 	umode_t mode;
631 	struct v9fs_inode *v9inode = V9FS_I(inode);
632 
633 	if ((stat->st_result_mask & P9_STATS_BASIC) == P9_STATS_BASIC) {
634 		inode->i_atime.tv_sec = stat->st_atime_sec;
635 		inode->i_atime.tv_nsec = stat->st_atime_nsec;
636 		inode->i_mtime.tv_sec = stat->st_mtime_sec;
637 		inode->i_mtime.tv_nsec = stat->st_mtime_nsec;
638 		inode->i_ctime.tv_sec = stat->st_ctime_sec;
639 		inode->i_ctime.tv_nsec = stat->st_ctime_nsec;
640 		inode->i_uid = stat->st_uid;
641 		inode->i_gid = stat->st_gid;
642 		set_nlink(inode, stat->st_nlink);
643 
644 		mode = stat->st_mode & S_IALLUGO;
645 		mode |= inode->i_mode & ~S_IALLUGO;
646 		inode->i_mode = mode;
647 
648 		if (!(flags & V9FS_STAT2INODE_KEEP_ISIZE))
649 			v9fs_i_size_write(inode, stat->st_size);
650 		inode->i_blocks = stat->st_blocks;
651 	} else {
652 		if (stat->st_result_mask & P9_STATS_ATIME) {
653 			inode->i_atime.tv_sec = stat->st_atime_sec;
654 			inode->i_atime.tv_nsec = stat->st_atime_nsec;
655 		}
656 		if (stat->st_result_mask & P9_STATS_MTIME) {
657 			inode->i_mtime.tv_sec = stat->st_mtime_sec;
658 			inode->i_mtime.tv_nsec = stat->st_mtime_nsec;
659 		}
660 		if (stat->st_result_mask & P9_STATS_CTIME) {
661 			inode->i_ctime.tv_sec = stat->st_ctime_sec;
662 			inode->i_ctime.tv_nsec = stat->st_ctime_nsec;
663 		}
664 		if (stat->st_result_mask & P9_STATS_UID)
665 			inode->i_uid = stat->st_uid;
666 		if (stat->st_result_mask & P9_STATS_GID)
667 			inode->i_gid = stat->st_gid;
668 		if (stat->st_result_mask & P9_STATS_NLINK)
669 			set_nlink(inode, stat->st_nlink);
670 		if (stat->st_result_mask & P9_STATS_MODE) {
671 			mode = stat->st_mode & S_IALLUGO;
672 			mode |= inode->i_mode & ~S_IALLUGO;
673 			inode->i_mode = mode;
674 		}
675 		if (!(flags & V9FS_STAT2INODE_KEEP_ISIZE) &&
676 		    stat->st_result_mask & P9_STATS_SIZE)
677 			v9fs_i_size_write(inode, stat->st_size);
678 		if (stat->st_result_mask & P9_STATS_BLOCKS)
679 			inode->i_blocks = stat->st_blocks;
680 	}
681 	if (stat->st_result_mask & P9_STATS_GEN)
682 		inode->i_generation = stat->st_gen;
683 
684 	/* Currently we don't support P9_STATS_BTIME and P9_STATS_DATA_VERSION
685 	 * because the inode structure does not have fields for them.
686 	 */
687 	v9inode->cache_validity &= ~V9FS_INO_INVALID_ATTR;
688 }
689 
690 static int
691 v9fs_vfs_symlink_dotl(struct user_namespace *mnt_userns, struct inode *dir,
692 		      struct dentry *dentry, const char *symname)
693 {
694 	int err;
695 	kgid_t gid;
696 	const unsigned char *name;
697 	struct p9_qid qid;
698 	struct inode *inode;
699 	struct p9_fid *dfid;
700 	struct p9_fid *fid = NULL;
701 	struct v9fs_session_info *v9ses;
702 
703 	name = dentry->d_name.name;
704 	p9_debug(P9_DEBUG_VFS, "%lu,%s,%s\n", dir->i_ino, name, symname);
705 	v9ses = v9fs_inode2v9ses(dir);
706 
707 	dfid = v9fs_parent_fid(dentry);
708 	if (IS_ERR(dfid)) {
709 		err = PTR_ERR(dfid);
710 		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
711 		return err;
712 	}
713 
714 	gid = v9fs_get_fsgid_for_create(dir);
715 
716 	/* Server doesn't alter fid on TSYMLINK. Hence no need to clone it. */
717 	err = p9_client_symlink(dfid, name, symname, gid, &qid);
718 
719 	if (err < 0) {
720 		p9_debug(P9_DEBUG_VFS, "p9_client_symlink failed %d\n", err);
721 		goto error;
722 	}
723 
724 	v9fs_invalidate_inode_attr(dir);
725 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
726 		/* Now walk from the parent so we can get an unopened fid. */
727 		fid = p9_client_walk(dfid, 1, &name, 1);
728 		if (IS_ERR(fid)) {
729 			err = PTR_ERR(fid);
730 			p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
731 				 err);
732 			goto error;
733 		}
734 
735 		/* instantiate inode and assign the unopened fid to dentry */
736 		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
737 		if (IS_ERR(inode)) {
738 			err = PTR_ERR(inode);
739 			p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n",
740 				 err);
741 			goto error;
742 		}
743 		v9fs_fid_add(dentry, &fid);
744 		d_instantiate(dentry, inode);
745 		err = 0;
746 	} else {
747 		/* Not in cached mode. No need to populate inode with stat */
748 		inode = v9fs_get_inode(dir->i_sb, S_IFLNK, 0);
749 		if (IS_ERR(inode)) {
750 			err = PTR_ERR(inode);
751 			goto error;
752 		}
753 		d_instantiate(dentry, inode);
754 	}
755 
756 error:
757 	p9_fid_put(fid);
758 	p9_fid_put(dfid);
759 	return err;
760 }
761 
762 /**
763  * v9fs_vfs_link_dotl - create a hardlink for dotl
764  * @old_dentry: dentry for file to link to
765  * @dir: inode destination for new link
766  * @dentry: dentry for link
767  *
768  */
769 
770 static int
771 v9fs_vfs_link_dotl(struct dentry *old_dentry, struct inode *dir,
772 		struct dentry *dentry)
773 {
774 	int err;
775 	struct p9_fid *dfid, *oldfid;
776 	struct v9fs_session_info *v9ses;
777 
778 	p9_debug(P9_DEBUG_VFS, "dir ino: %lu, old_name: %pd, new_name: %pd\n",
779 		 dir->i_ino, old_dentry, dentry);
780 
781 	v9ses = v9fs_inode2v9ses(dir);
782 	dfid = v9fs_parent_fid(dentry);
783 	if (IS_ERR(dfid))
784 		return PTR_ERR(dfid);
785 
786 	oldfid = v9fs_fid_lookup(old_dentry);
787 	if (IS_ERR(oldfid)) {
788 		p9_fid_put(dfid);
789 		return PTR_ERR(oldfid);
790 	}
791 
792 	err = p9_client_link(dfid, oldfid, dentry->d_name.name);
793 
794 	p9_fid_put(dfid);
795 	p9_fid_put(oldfid);
796 	if (err < 0) {
797 		p9_debug(P9_DEBUG_VFS, "p9_client_link failed %d\n", err);
798 		return err;
799 	}
800 
801 	v9fs_invalidate_inode_attr(dir);
802 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
803 		/* Get the latest stat info from server. */
804 		struct p9_fid *fid;
805 
806 		fid = v9fs_fid_lookup(old_dentry);
807 		if (IS_ERR(fid))
808 			return PTR_ERR(fid);
809 
810 		v9fs_refresh_inode_dotl(fid, d_inode(old_dentry));
811 		p9_fid_put(fid);
812 	}
813 	ihold(d_inode(old_dentry));
814 	d_instantiate(dentry, d_inode(old_dentry));
815 
816 	return err;
817 }
818 
819 /**
820  * v9fs_vfs_mknod_dotl - create a special file
821  * @mnt_userns: The user namespace of the mount
822  * @dir: inode destination for new link
823  * @dentry: dentry for file
824  * @omode: mode for creation
825  * @rdev: device associated with special file
826  *
827  */
828 static int
829 v9fs_vfs_mknod_dotl(struct user_namespace *mnt_userns, struct inode *dir,
830 		    struct dentry *dentry, umode_t omode, dev_t rdev)
831 {
832 	int err;
833 	kgid_t gid;
834 	const unsigned char *name;
835 	umode_t mode;
836 	struct v9fs_session_info *v9ses;
837 	struct p9_fid *fid = NULL, *dfid = NULL;
838 	struct inode *inode;
839 	struct p9_qid qid;
840 	struct posix_acl *dacl = NULL, *pacl = NULL;
841 
842 	p9_debug(P9_DEBUG_VFS, " %lu,%pd mode: %x MAJOR: %u MINOR: %u\n",
843 		 dir->i_ino, dentry, omode,
844 		 MAJOR(rdev), MINOR(rdev));
845 
846 	v9ses = v9fs_inode2v9ses(dir);
847 	dfid = v9fs_parent_fid(dentry);
848 	if (IS_ERR(dfid)) {
849 		err = PTR_ERR(dfid);
850 		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
851 		goto error;
852 	}
853 
854 	gid = v9fs_get_fsgid_for_create(dir);
855 	mode = omode;
856 	/* Update mode based on ACL value */
857 	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
858 	if (err) {
859 		p9_debug(P9_DEBUG_VFS, "Failed to get acl values in mknod %d\n",
860 			 err);
861 		goto error;
862 	}
863 	name = dentry->d_name.name;
864 
865 	err = p9_client_mknod_dotl(dfid, name, mode, rdev, gid, &qid);
866 	if (err < 0)
867 		goto error;
868 
869 	v9fs_invalidate_inode_attr(dir);
870 	fid = p9_client_walk(dfid, 1, &name, 1);
871 	if (IS_ERR(fid)) {
872 		err = PTR_ERR(fid);
873 		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
874 			 err);
875 		goto error;
876 	}
877 
878 	/* instantiate inode and assign the unopened fid to the dentry */
879 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
880 		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
881 		if (IS_ERR(inode)) {
882 			err = PTR_ERR(inode);
883 			p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n",
884 				 err);
885 			goto error;
886 		}
887 		v9fs_set_create_acl(inode, fid, dacl, pacl);
888 		v9fs_fid_add(dentry, &fid);
889 		d_instantiate(dentry, inode);
890 		err = 0;
891 	} else {
892 		/*
893 		 * Not in cached mode. No need to populate inode with stat.
894 		 * socket syscall returns a fd, so we need instantiate
895 		 */
896 		inode = v9fs_get_inode(dir->i_sb, mode, rdev);
897 		if (IS_ERR(inode)) {
898 			err = PTR_ERR(inode);
899 			goto error;
900 		}
901 		v9fs_set_create_acl(inode, fid, dacl, pacl);
902 		d_instantiate(dentry, inode);
903 	}
904 error:
905 	p9_fid_put(fid);
906 	v9fs_put_acl(dacl, pacl);
907 	p9_fid_put(dfid);
908 
909 	return err;
910 }
911 
912 /**
913  * v9fs_vfs_get_link_dotl - follow a symlink path
914  * @dentry: dentry for symlink
915  * @inode: inode for symlink
916  * @done: destructor for return value
917  */
918 
919 static const char *
920 v9fs_vfs_get_link_dotl(struct dentry *dentry,
921 		       struct inode *inode,
922 		       struct delayed_call *done)
923 {
924 	struct p9_fid *fid;
925 	char *target;
926 	int retval;
927 
928 	if (!dentry)
929 		return ERR_PTR(-ECHILD);
930 
931 	p9_debug(P9_DEBUG_VFS, "%pd\n", dentry);
932 
933 	fid = v9fs_fid_lookup(dentry);
934 	if (IS_ERR(fid))
935 		return ERR_CAST(fid);
936 	retval = p9_client_readlink(fid, &target);
937 	p9_fid_put(fid);
938 	if (retval)
939 		return ERR_PTR(retval);
940 	set_delayed_call(done, kfree_link, target);
941 	return target;
942 }
943 
944 int v9fs_refresh_inode_dotl(struct p9_fid *fid, struct inode *inode)
945 {
946 	struct p9_stat_dotl *st;
947 	struct v9fs_session_info *v9ses;
948 	unsigned int flags;
949 
950 	v9ses = v9fs_inode2v9ses(inode);
951 	st = p9_client_getattr_dotl(fid, P9_STATS_ALL);
952 	if (IS_ERR(st))
953 		return PTR_ERR(st);
954 	/*
955 	 * Don't update inode if the file type is different
956 	 */
957 	if (inode_wrong_type(inode, st->st_mode))
958 		goto out;
959 
960 	/*
961 	 * We don't want to refresh inode->i_size,
962 	 * because we may have cached data
963 	 */
964 	flags = (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) ?
965 		V9FS_STAT2INODE_KEEP_ISIZE : 0;
966 	v9fs_stat2inode_dotl(st, inode, flags);
967 out:
968 	kfree(st);
969 	return 0;
970 }
971 
972 const struct inode_operations v9fs_dir_inode_operations_dotl = {
973 	.create = v9fs_vfs_create_dotl,
974 	.atomic_open = v9fs_vfs_atomic_open_dotl,
975 	.lookup = v9fs_vfs_lookup,
976 	.link = v9fs_vfs_link_dotl,
977 	.symlink = v9fs_vfs_symlink_dotl,
978 	.unlink = v9fs_vfs_unlink,
979 	.mkdir = v9fs_vfs_mkdir_dotl,
980 	.rmdir = v9fs_vfs_rmdir,
981 	.mknod = v9fs_vfs_mknod_dotl,
982 	.rename = v9fs_vfs_rename,
983 	.getattr = v9fs_vfs_getattr_dotl,
984 	.setattr = v9fs_vfs_setattr_dotl,
985 	.listxattr = v9fs_listxattr,
986 	.get_acl = v9fs_iop_get_acl,
987 };
988 
989 const struct inode_operations v9fs_file_inode_operations_dotl = {
990 	.getattr = v9fs_vfs_getattr_dotl,
991 	.setattr = v9fs_vfs_setattr_dotl,
992 	.listxattr = v9fs_listxattr,
993 	.get_acl = v9fs_iop_get_acl,
994 };
995 
996 const struct inode_operations v9fs_symlink_inode_operations_dotl = {
997 	.get_link = v9fs_vfs_get_link_dotl,
998 	.getattr = v9fs_vfs_getattr_dotl,
999 	.setattr = v9fs_vfs_setattr_dotl,
1000 	.listxattr = v9fs_listxattr,
1001 };
1002