xref: /openbmc/linux/fs/9p/vfs_inode_dotl.c (revision f68f2ff9)
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 		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 error;
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 error;
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 	p9_client_clunk(dfid);
302 	if (IS_ERR(fid)) {
303 		err = PTR_ERR(fid);
304 		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
305 		fid = NULL;
306 		goto error;
307 	}
308 	inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
309 	if (IS_ERR(inode)) {
310 		err = PTR_ERR(inode);
311 		p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n", err);
312 		goto error;
313 	}
314 	/* Now set the ACL based on the default value */
315 	v9fs_set_create_acl(inode, fid, dacl, pacl);
316 
317 	v9fs_fid_add(dentry, fid);
318 	d_instantiate(dentry, inode);
319 
320 	v9inode = V9FS_I(inode);
321 	mutex_lock(&v9inode->v_mutex);
322 	if ((v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) &&
323 	    !v9inode->writeback_fid &&
324 	    ((flags & O_ACCMODE) != O_RDONLY)) {
325 		/*
326 		 * clone a fid and add it to writeback_fid
327 		 * we do it during open time instead of
328 		 * page dirty time via write_begin/page_mkwrite
329 		 * because we want write after unlink usecase
330 		 * to work.
331 		 */
332 		inode_fid = v9fs_writeback_fid(dentry);
333 		if (IS_ERR(inode_fid)) {
334 			err = PTR_ERR(inode_fid);
335 			mutex_unlock(&v9inode->v_mutex);
336 			goto err_clunk_old_fid;
337 		}
338 		v9inode->writeback_fid = (void *) inode_fid;
339 	}
340 	mutex_unlock(&v9inode->v_mutex);
341 	/* Since we are opening a file, assign the open fid to the file */
342 	err = finish_open(file, dentry, generic_file_open);
343 	if (err)
344 		goto err_clunk_old_fid;
345 	file->private_data = ofid;
346 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
347 		fscache_use_cookie(v9fs_inode_cookie(v9inode),
348 				   file->f_mode & FMODE_WRITE);
349 	v9fs_open_fid_add(inode, ofid);
350 	file->f_mode |= FMODE_CREATED;
351 out:
352 	v9fs_put_acl(dacl, pacl);
353 	dput(res);
354 	return err;
355 
356 error:
357 	if (fid)
358 		p9_client_clunk(fid);
359 err_clunk_old_fid:
360 	if (ofid)
361 		p9_client_clunk(ofid);
362 	goto out;
363 }
364 
365 /**
366  * v9fs_vfs_mkdir_dotl - VFS mkdir hook to create a directory
367  * @mnt_userns: The user namespace of the mount
368  * @dir:  inode that is being unlinked
369  * @dentry: dentry that is being unlinked
370  * @omode: mode for new directory
371  *
372  */
373 
374 static int v9fs_vfs_mkdir_dotl(struct user_namespace *mnt_userns,
375 			       struct inode *dir, struct dentry *dentry,
376 			       umode_t omode)
377 {
378 	int err;
379 	struct v9fs_session_info *v9ses;
380 	struct p9_fid *fid = NULL, *dfid = NULL;
381 	kgid_t gid;
382 	const unsigned char *name;
383 	umode_t mode;
384 	struct inode *inode;
385 	struct p9_qid qid;
386 	struct posix_acl *dacl = NULL, *pacl = NULL;
387 
388 	p9_debug(P9_DEBUG_VFS, "name %pd\n", dentry);
389 	err = 0;
390 	v9ses = v9fs_inode2v9ses(dir);
391 
392 	omode |= S_IFDIR;
393 	if (dir->i_mode & S_ISGID)
394 		omode |= S_ISGID;
395 
396 	dfid = v9fs_parent_fid(dentry);
397 	if (IS_ERR(dfid)) {
398 		err = PTR_ERR(dfid);
399 		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
400 		dfid = NULL;
401 		goto error;
402 	}
403 
404 	gid = v9fs_get_fsgid_for_create(dir);
405 	mode = omode;
406 	/* Update mode based on ACL value */
407 	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
408 	if (err) {
409 		p9_debug(P9_DEBUG_VFS, "Failed to get acl values in mkdir %d\n",
410 			 err);
411 		goto error;
412 	}
413 	name = dentry->d_name.name;
414 	err = p9_client_mkdir_dotl(dfid, name, mode, gid, &qid);
415 	if (err < 0)
416 		goto error;
417 	fid = p9_client_walk(dfid, 1, &name, 1);
418 	if (IS_ERR(fid)) {
419 		err = PTR_ERR(fid);
420 		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
421 			 err);
422 		fid = NULL;
423 		goto error;
424 	}
425 
426 	/* instantiate inode and assign the unopened fid to the dentry */
427 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
428 		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
429 		if (IS_ERR(inode)) {
430 			err = PTR_ERR(inode);
431 			p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n",
432 				 err);
433 			goto error;
434 		}
435 		v9fs_fid_add(dentry, fid);
436 		v9fs_set_create_acl(inode, fid, dacl, pacl);
437 		d_instantiate(dentry, inode);
438 		fid = NULL;
439 		err = 0;
440 	} else {
441 		/*
442 		 * Not in cached mode. No need to populate
443 		 * inode with stat. We need to get an inode
444 		 * so that we can set the acl with dentry
445 		 */
446 		inode = v9fs_get_inode(dir->i_sb, mode, 0);
447 		if (IS_ERR(inode)) {
448 			err = PTR_ERR(inode);
449 			goto error;
450 		}
451 		v9fs_set_create_acl(inode, fid, dacl, pacl);
452 		d_instantiate(dentry, inode);
453 	}
454 	inc_nlink(dir);
455 	v9fs_invalidate_inode_attr(dir);
456 error:
457 	if (fid)
458 		p9_client_clunk(fid);
459 	v9fs_put_acl(dacl, pacl);
460 	p9_client_clunk(dfid);
461 	return err;
462 }
463 
464 static int
465 v9fs_vfs_getattr_dotl(struct user_namespace *mnt_userns,
466 		      const struct path *path, struct kstat *stat,
467 		      u32 request_mask, unsigned int flags)
468 {
469 	struct dentry *dentry = path->dentry;
470 	struct v9fs_session_info *v9ses;
471 	struct p9_fid *fid;
472 	struct p9_stat_dotl *st;
473 
474 	p9_debug(P9_DEBUG_VFS, "dentry: %p\n", dentry);
475 	v9ses = v9fs_dentry2v9ses(dentry);
476 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
477 		generic_fillattr(&init_user_ns, d_inode(dentry), stat);
478 		return 0;
479 	}
480 	fid = v9fs_fid_lookup(dentry);
481 	if (IS_ERR(fid))
482 		return PTR_ERR(fid);
483 
484 	/* Ask for all the fields in stat structure. Server will return
485 	 * whatever it supports
486 	 */
487 
488 	st = p9_client_getattr_dotl(fid, P9_STATS_ALL);
489 	p9_client_clunk(fid);
490 	if (IS_ERR(st))
491 		return PTR_ERR(st);
492 
493 	v9fs_stat2inode_dotl(st, d_inode(dentry), 0);
494 	generic_fillattr(&init_user_ns, d_inode(dentry), stat);
495 	/* Change block size to what the server returned */
496 	stat->blksize = st->st_blksize;
497 
498 	kfree(st);
499 	return 0;
500 }
501 
502 /*
503  * Attribute flags.
504  */
505 #define P9_ATTR_MODE		(1 << 0)
506 #define P9_ATTR_UID		(1 << 1)
507 #define P9_ATTR_GID		(1 << 2)
508 #define P9_ATTR_SIZE		(1 << 3)
509 #define P9_ATTR_ATIME		(1 << 4)
510 #define P9_ATTR_MTIME		(1 << 5)
511 #define P9_ATTR_CTIME		(1 << 6)
512 #define P9_ATTR_ATIME_SET	(1 << 7)
513 #define P9_ATTR_MTIME_SET	(1 << 8)
514 
515 struct dotl_iattr_map {
516 	int iattr_valid;
517 	int p9_iattr_valid;
518 };
519 
520 static int v9fs_mapped_iattr_valid(int iattr_valid)
521 {
522 	int i;
523 	int p9_iattr_valid = 0;
524 	struct dotl_iattr_map dotl_iattr_map[] = {
525 		{ ATTR_MODE,		P9_ATTR_MODE },
526 		{ ATTR_UID,		P9_ATTR_UID },
527 		{ ATTR_GID,		P9_ATTR_GID },
528 		{ ATTR_SIZE,		P9_ATTR_SIZE },
529 		{ ATTR_ATIME,		P9_ATTR_ATIME },
530 		{ ATTR_MTIME,		P9_ATTR_MTIME },
531 		{ ATTR_CTIME,		P9_ATTR_CTIME },
532 		{ ATTR_ATIME_SET,	P9_ATTR_ATIME_SET },
533 		{ ATTR_MTIME_SET,	P9_ATTR_MTIME_SET },
534 	};
535 	for (i = 0; i < ARRAY_SIZE(dotl_iattr_map); i++) {
536 		if (iattr_valid & dotl_iattr_map[i].iattr_valid)
537 			p9_iattr_valid |= dotl_iattr_map[i].p9_iattr_valid;
538 	}
539 	return p9_iattr_valid;
540 }
541 
542 /**
543  * v9fs_vfs_setattr_dotl - set file metadata
544  * @mnt_userns: The user namespace of the mount
545  * @dentry: file whose metadata to set
546  * @iattr: metadata assignment structure
547  *
548  */
549 
550 int v9fs_vfs_setattr_dotl(struct user_namespace *mnt_userns,
551 			  struct dentry *dentry, struct iattr *iattr)
552 {
553 	int retval, use_dentry = 0;
554 	struct p9_fid *fid = NULL;
555 	struct p9_iattr_dotl p9attr = {
556 		.uid = INVALID_UID,
557 		.gid = INVALID_GID,
558 	};
559 	struct inode *inode = d_inode(dentry);
560 
561 	p9_debug(P9_DEBUG_VFS, "\n");
562 
563 	retval = setattr_prepare(&init_user_ns, dentry, iattr);
564 	if (retval)
565 		return retval;
566 
567 	p9attr.valid = v9fs_mapped_iattr_valid(iattr->ia_valid);
568 	if (iattr->ia_valid & ATTR_MODE)
569 		p9attr.mode = iattr->ia_mode;
570 	if (iattr->ia_valid & ATTR_UID)
571 		p9attr.uid = iattr->ia_uid;
572 	if (iattr->ia_valid & ATTR_GID)
573 		p9attr.gid = iattr->ia_gid;
574 	if (iattr->ia_valid & ATTR_SIZE)
575 		p9attr.size = iattr->ia_size;
576 	if (iattr->ia_valid & ATTR_ATIME_SET) {
577 		p9attr.atime_sec = iattr->ia_atime.tv_sec;
578 		p9attr.atime_nsec = iattr->ia_atime.tv_nsec;
579 	}
580 	if (iattr->ia_valid & ATTR_MTIME_SET) {
581 		p9attr.mtime_sec = iattr->ia_mtime.tv_sec;
582 		p9attr.mtime_nsec = iattr->ia_mtime.tv_nsec;
583 	}
584 
585 	if (iattr->ia_valid & ATTR_FILE) {
586 		fid = iattr->ia_file->private_data;
587 		WARN_ON(!fid);
588 	}
589 	if (!fid) {
590 		fid = v9fs_fid_lookup(dentry);
591 		use_dentry = 1;
592 	}
593 	if (IS_ERR(fid))
594 		return PTR_ERR(fid);
595 
596 	/* Write all dirty data */
597 	if (S_ISREG(inode->i_mode))
598 		filemap_write_and_wait(inode->i_mapping);
599 
600 	retval = p9_client_setattr(fid, &p9attr);
601 	if (retval < 0) {
602 		if (use_dentry)
603 			p9_client_clunk(fid);
604 		return retval;
605 	}
606 
607 	if ((iattr->ia_valid & ATTR_SIZE) &&
608 	    iattr->ia_size != i_size_read(inode))
609 		truncate_setsize(inode, iattr->ia_size);
610 
611 	v9fs_invalidate_inode_attr(inode);
612 	setattr_copy(&init_user_ns, inode, iattr);
613 	mark_inode_dirty(inode);
614 	if (iattr->ia_valid & ATTR_MODE) {
615 		/* We also want to update ACL when we update mode bits */
616 		retval = v9fs_acl_chmod(inode, fid);
617 		if (retval < 0) {
618 			if (use_dentry)
619 				p9_client_clunk(fid);
620 			return retval;
621 		}
622 	}
623 	if (use_dentry)
624 		p9_client_clunk(fid);
625 
626 	return 0;
627 }
628 
629 /**
630  * v9fs_stat2inode_dotl - populate an inode structure with stat info
631  * @stat: stat structure
632  * @inode: inode to populate
633  * @flags: ctrl flags (e.g. V9FS_STAT2INODE_KEEP_ISIZE)
634  *
635  */
636 
637 void
638 v9fs_stat2inode_dotl(struct p9_stat_dotl *stat, struct inode *inode,
639 		      unsigned int flags)
640 {
641 	umode_t mode;
642 	struct v9fs_inode *v9inode = V9FS_I(inode);
643 
644 	if ((stat->st_result_mask & P9_STATS_BASIC) == P9_STATS_BASIC) {
645 		inode->i_atime.tv_sec = stat->st_atime_sec;
646 		inode->i_atime.tv_nsec = stat->st_atime_nsec;
647 		inode->i_mtime.tv_sec = stat->st_mtime_sec;
648 		inode->i_mtime.tv_nsec = stat->st_mtime_nsec;
649 		inode->i_ctime.tv_sec = stat->st_ctime_sec;
650 		inode->i_ctime.tv_nsec = stat->st_ctime_nsec;
651 		inode->i_uid = stat->st_uid;
652 		inode->i_gid = stat->st_gid;
653 		set_nlink(inode, stat->st_nlink);
654 
655 		mode = stat->st_mode & S_IALLUGO;
656 		mode |= inode->i_mode & ~S_IALLUGO;
657 		inode->i_mode = mode;
658 
659 		if (!(flags & V9FS_STAT2INODE_KEEP_ISIZE))
660 			v9fs_i_size_write(inode, stat->st_size);
661 		inode->i_blocks = stat->st_blocks;
662 	} else {
663 		if (stat->st_result_mask & P9_STATS_ATIME) {
664 			inode->i_atime.tv_sec = stat->st_atime_sec;
665 			inode->i_atime.tv_nsec = stat->st_atime_nsec;
666 		}
667 		if (stat->st_result_mask & P9_STATS_MTIME) {
668 			inode->i_mtime.tv_sec = stat->st_mtime_sec;
669 			inode->i_mtime.tv_nsec = stat->st_mtime_nsec;
670 		}
671 		if (stat->st_result_mask & P9_STATS_CTIME) {
672 			inode->i_ctime.tv_sec = stat->st_ctime_sec;
673 			inode->i_ctime.tv_nsec = stat->st_ctime_nsec;
674 		}
675 		if (stat->st_result_mask & P9_STATS_UID)
676 			inode->i_uid = stat->st_uid;
677 		if (stat->st_result_mask & P9_STATS_GID)
678 			inode->i_gid = stat->st_gid;
679 		if (stat->st_result_mask & P9_STATS_NLINK)
680 			set_nlink(inode, stat->st_nlink);
681 		if (stat->st_result_mask & P9_STATS_MODE) {
682 			mode = stat->st_mode & S_IALLUGO;
683 			mode |= inode->i_mode & ~S_IALLUGO;
684 			inode->i_mode = mode;
685 		}
686 		if (!(flags & V9FS_STAT2INODE_KEEP_ISIZE) &&
687 		    stat->st_result_mask & P9_STATS_SIZE)
688 			v9fs_i_size_write(inode, stat->st_size);
689 		if (stat->st_result_mask & P9_STATS_BLOCKS)
690 			inode->i_blocks = stat->st_blocks;
691 	}
692 	if (stat->st_result_mask & P9_STATS_GEN)
693 		inode->i_generation = stat->st_gen;
694 
695 	/* Currently we don't support P9_STATS_BTIME and P9_STATS_DATA_VERSION
696 	 * because the inode structure does not have fields for them.
697 	 */
698 	v9inode->cache_validity &= ~V9FS_INO_INVALID_ATTR;
699 }
700 
701 static int
702 v9fs_vfs_symlink_dotl(struct user_namespace *mnt_userns, struct inode *dir,
703 		      struct dentry *dentry, const char *symname)
704 {
705 	int err;
706 	kgid_t gid;
707 	const unsigned char *name;
708 	struct p9_qid qid;
709 	struct inode *inode;
710 	struct p9_fid *dfid;
711 	struct p9_fid *fid = NULL;
712 	struct v9fs_session_info *v9ses;
713 
714 	name = dentry->d_name.name;
715 	p9_debug(P9_DEBUG_VFS, "%lu,%s,%s\n", dir->i_ino, name, symname);
716 	v9ses = v9fs_inode2v9ses(dir);
717 
718 	dfid = v9fs_parent_fid(dentry);
719 	if (IS_ERR(dfid)) {
720 		err = PTR_ERR(dfid);
721 		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
722 		return err;
723 	}
724 
725 	gid = v9fs_get_fsgid_for_create(dir);
726 
727 	/* Server doesn't alter fid on TSYMLINK. Hence no need to clone it. */
728 	err = p9_client_symlink(dfid, name, symname, gid, &qid);
729 
730 	if (err < 0) {
731 		p9_debug(P9_DEBUG_VFS, "p9_client_symlink failed %d\n", err);
732 		goto error;
733 	}
734 
735 	v9fs_invalidate_inode_attr(dir);
736 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
737 		/* Now walk from the parent so we can get an unopened fid. */
738 		fid = p9_client_walk(dfid, 1, &name, 1);
739 		if (IS_ERR(fid)) {
740 			err = PTR_ERR(fid);
741 			p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
742 				 err);
743 			fid = NULL;
744 			goto error;
745 		}
746 
747 		/* instantiate inode and assign the unopened fid to dentry */
748 		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
749 		if (IS_ERR(inode)) {
750 			err = PTR_ERR(inode);
751 			p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n",
752 				 err);
753 			goto error;
754 		}
755 		v9fs_fid_add(dentry, fid);
756 		d_instantiate(dentry, inode);
757 		fid = NULL;
758 		err = 0;
759 	} else {
760 		/* Not in cached mode. No need to populate inode with stat */
761 		inode = v9fs_get_inode(dir->i_sb, S_IFLNK, 0);
762 		if (IS_ERR(inode)) {
763 			err = PTR_ERR(inode);
764 			goto error;
765 		}
766 		d_instantiate(dentry, inode);
767 	}
768 
769 error:
770 	if (fid)
771 		p9_client_clunk(fid);
772 
773 	p9_client_clunk(dfid);
774 	return err;
775 }
776 
777 /**
778  * v9fs_vfs_link_dotl - create a hardlink for dotl
779  * @old_dentry: dentry for file to link to
780  * @dir: inode destination for new link
781  * @dentry: dentry for link
782  *
783  */
784 
785 static int
786 v9fs_vfs_link_dotl(struct dentry *old_dentry, struct inode *dir,
787 		struct dentry *dentry)
788 {
789 	int err;
790 	struct p9_fid *dfid, *oldfid;
791 	struct v9fs_session_info *v9ses;
792 
793 	p9_debug(P9_DEBUG_VFS, "dir ino: %lu, old_name: %pd, new_name: %pd\n",
794 		 dir->i_ino, old_dentry, dentry);
795 
796 	v9ses = v9fs_inode2v9ses(dir);
797 	dfid = v9fs_parent_fid(dentry);
798 	if (IS_ERR(dfid))
799 		return PTR_ERR(dfid);
800 
801 	oldfid = v9fs_fid_lookup(old_dentry);
802 	if (IS_ERR(oldfid)) {
803 		p9_client_clunk(dfid);
804 		return PTR_ERR(oldfid);
805 	}
806 
807 	err = p9_client_link(dfid, oldfid, dentry->d_name.name);
808 
809 	p9_client_clunk(dfid);
810 	p9_client_clunk(oldfid);
811 	if (err < 0) {
812 		p9_debug(P9_DEBUG_VFS, "p9_client_link failed %d\n", err);
813 		return err;
814 	}
815 
816 	v9fs_invalidate_inode_attr(dir);
817 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
818 		/* Get the latest stat info from server. */
819 		struct p9_fid *fid;
820 
821 		fid = v9fs_fid_lookup(old_dentry);
822 		if (IS_ERR(fid))
823 			return PTR_ERR(fid);
824 
825 		v9fs_refresh_inode_dotl(fid, d_inode(old_dentry));
826 		p9_client_clunk(fid);
827 	}
828 	ihold(d_inode(old_dentry));
829 	d_instantiate(dentry, d_inode(old_dentry));
830 
831 	return err;
832 }
833 
834 /**
835  * v9fs_vfs_mknod_dotl - create a special file
836  * @mnt_userns: The user namespace of the mount
837  * @dir: inode destination for new link
838  * @dentry: dentry for file
839  * @omode: mode for creation
840  * @rdev: device associated with special file
841  *
842  */
843 static int
844 v9fs_vfs_mknod_dotl(struct user_namespace *mnt_userns, struct inode *dir,
845 		    struct dentry *dentry, umode_t omode, dev_t rdev)
846 {
847 	int err;
848 	kgid_t gid;
849 	const unsigned char *name;
850 	umode_t mode;
851 	struct v9fs_session_info *v9ses;
852 	struct p9_fid *fid = NULL, *dfid = NULL;
853 	struct inode *inode;
854 	struct p9_qid qid;
855 	struct posix_acl *dacl = NULL, *pacl = NULL;
856 
857 	p9_debug(P9_DEBUG_VFS, " %lu,%pd mode: %x MAJOR: %u MINOR: %u\n",
858 		 dir->i_ino, dentry, omode,
859 		 MAJOR(rdev), MINOR(rdev));
860 
861 	v9ses = v9fs_inode2v9ses(dir);
862 	dfid = v9fs_parent_fid(dentry);
863 	if (IS_ERR(dfid)) {
864 		err = PTR_ERR(dfid);
865 		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
866 		dfid = NULL;
867 		goto error;
868 	}
869 
870 	gid = v9fs_get_fsgid_for_create(dir);
871 	mode = omode;
872 	/* Update mode based on ACL value */
873 	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
874 	if (err) {
875 		p9_debug(P9_DEBUG_VFS, "Failed to get acl values in mknod %d\n",
876 			 err);
877 		goto error;
878 	}
879 	name = dentry->d_name.name;
880 
881 	err = p9_client_mknod_dotl(dfid, name, mode, rdev, gid, &qid);
882 	if (err < 0)
883 		goto error;
884 
885 	v9fs_invalidate_inode_attr(dir);
886 	fid = p9_client_walk(dfid, 1, &name, 1);
887 	if (IS_ERR(fid)) {
888 		err = PTR_ERR(fid);
889 		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
890 			 err);
891 		fid = NULL;
892 		goto error;
893 	}
894 
895 	/* instantiate inode and assign the unopened fid to the dentry */
896 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
897 		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
898 		if (IS_ERR(inode)) {
899 			err = PTR_ERR(inode);
900 			p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n",
901 				 err);
902 			goto error;
903 		}
904 		v9fs_set_create_acl(inode, fid, dacl, pacl);
905 		v9fs_fid_add(dentry, fid);
906 		d_instantiate(dentry, inode);
907 		fid = NULL;
908 		err = 0;
909 	} else {
910 		/*
911 		 * Not in cached mode. No need to populate inode with stat.
912 		 * socket syscall returns a fd, so we need instantiate
913 		 */
914 		inode = v9fs_get_inode(dir->i_sb, mode, rdev);
915 		if (IS_ERR(inode)) {
916 			err = PTR_ERR(inode);
917 			goto error;
918 		}
919 		v9fs_set_create_acl(inode, fid, dacl, pacl);
920 		d_instantiate(dentry, inode);
921 	}
922 error:
923 	if (fid)
924 		p9_client_clunk(fid);
925 	v9fs_put_acl(dacl, pacl);
926 	p9_client_clunk(dfid);
927 
928 	return err;
929 }
930 
931 /**
932  * v9fs_vfs_get_link_dotl - follow a symlink path
933  * @dentry: dentry for symlink
934  * @inode: inode for symlink
935  * @done: destructor for return value
936  */
937 
938 static const char *
939 v9fs_vfs_get_link_dotl(struct dentry *dentry,
940 		       struct inode *inode,
941 		       struct delayed_call *done)
942 {
943 	struct p9_fid *fid;
944 	char *target;
945 	int retval;
946 
947 	if (!dentry)
948 		return ERR_PTR(-ECHILD);
949 
950 	p9_debug(P9_DEBUG_VFS, "%pd\n", dentry);
951 
952 	fid = v9fs_fid_lookup(dentry);
953 	if (IS_ERR(fid))
954 		return ERR_CAST(fid);
955 	retval = p9_client_readlink(fid, &target);
956 	p9_client_clunk(fid);
957 	if (retval)
958 		return ERR_PTR(retval);
959 	set_delayed_call(done, kfree_link, target);
960 	return target;
961 }
962 
963 int v9fs_refresh_inode_dotl(struct p9_fid *fid, struct inode *inode)
964 {
965 	struct p9_stat_dotl *st;
966 	struct v9fs_session_info *v9ses;
967 	unsigned int flags;
968 
969 	v9ses = v9fs_inode2v9ses(inode);
970 	st = p9_client_getattr_dotl(fid, P9_STATS_ALL);
971 	if (IS_ERR(st))
972 		return PTR_ERR(st);
973 	/*
974 	 * Don't update inode if the file type is different
975 	 */
976 	if (inode_wrong_type(inode, st->st_mode))
977 		goto out;
978 
979 	/*
980 	 * We don't want to refresh inode->i_size,
981 	 * because we may have cached data
982 	 */
983 	flags = (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) ?
984 		V9FS_STAT2INODE_KEEP_ISIZE : 0;
985 	v9fs_stat2inode_dotl(st, inode, flags);
986 out:
987 	kfree(st);
988 	return 0;
989 }
990 
991 const struct inode_operations v9fs_dir_inode_operations_dotl = {
992 	.create = v9fs_vfs_create_dotl,
993 	.atomic_open = v9fs_vfs_atomic_open_dotl,
994 	.lookup = v9fs_vfs_lookup,
995 	.link = v9fs_vfs_link_dotl,
996 	.symlink = v9fs_vfs_symlink_dotl,
997 	.unlink = v9fs_vfs_unlink,
998 	.mkdir = v9fs_vfs_mkdir_dotl,
999 	.rmdir = v9fs_vfs_rmdir,
1000 	.mknod = v9fs_vfs_mknod_dotl,
1001 	.rename = v9fs_vfs_rename,
1002 	.getattr = v9fs_vfs_getattr_dotl,
1003 	.setattr = v9fs_vfs_setattr_dotl,
1004 	.listxattr = v9fs_listxattr,
1005 	.get_acl = v9fs_iop_get_acl,
1006 };
1007 
1008 const struct inode_operations v9fs_file_inode_operations_dotl = {
1009 	.getattr = v9fs_vfs_getattr_dotl,
1010 	.setattr = v9fs_vfs_setattr_dotl,
1011 	.listxattr = v9fs_listxattr,
1012 	.get_acl = v9fs_iop_get_acl,
1013 };
1014 
1015 const struct inode_operations v9fs_symlink_inode_operations_dotl = {
1016 	.get_link = v9fs_vfs_get_link_dotl,
1017 	.getattr = v9fs_vfs_getattr_dotl,
1018 	.setattr = v9fs_vfs_setattr_dotl,
1019 	.listxattr = v9fs_listxattr,
1020 };
1021