1 // SPDX-License-Identifier: GPL-2.0-only
3 * This file contains vfs inode ops for the 9P2000 protocol.
5 * Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
6 * Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
9 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
11 #include <linux/module.h>
12 #include <linux/errno.h>
14 #include <linux/file.h>
15 #include <linux/pagemap.h>
16 #include <linux/stat.h>
17 #include <linux/string.h>
18 #include <linux/inet.h>
19 #include <linux/namei.h>
20 #include <linux/idr.h>
21 #include <linux/sched.h>
22 #include <linux/slab.h>
23 #include <linux/xattr.h>
24 #include <linux/posix_acl.h>
25 #include <net/9p/9p.h>
26 #include <net/9p/client.h>
35 static const struct inode_operations v9fs_dir_inode_operations;
36 static const struct inode_operations v9fs_dir_inode_operations_dotu;
37 static const struct inode_operations v9fs_file_inode_operations;
38 static const struct inode_operations v9fs_symlink_inode_operations;
41 * unixmode2p9mode - convert unix mode bits to plan 9
42 * @v9ses: v9fs session information
43 * @mode: mode to convert
47 static u32 unixmode2p9mode(struct v9fs_session_info *v9ses, umode_t mode)
54 if (v9fs_proto_dotu(v9ses)) {
55 if (v9ses->nodev == 0) {
59 res |= P9_DMNAMEDPIPE;
66 if ((mode & S_ISUID) == S_ISUID)
68 if ((mode & S_ISGID) == S_ISGID)
70 if ((mode & S_ISVTX) == S_ISVTX)
77 * p9mode2perm- convert plan9 mode bits to unix permission bits
78 * @v9ses: v9fs session information
79 * @stat: p9_wstat from which mode need to be derived
82 static int p9mode2perm(struct v9fs_session_info *v9ses,
83 struct p9_wstat *stat)
86 int mode = stat->mode;
88 res = mode & S_IALLUGO;
89 if (v9fs_proto_dotu(v9ses)) {
90 if ((mode & P9_DMSETUID) == P9_DMSETUID)
93 if ((mode & P9_DMSETGID) == P9_DMSETGID)
96 if ((mode & P9_DMSETVTX) == P9_DMSETVTX)
103 * p9mode2unixmode- convert plan9 mode bits to unix mode bits
104 * @v9ses: v9fs session information
105 * @stat: p9_wstat from which mode need to be derived
106 * @rdev: major number, minor number in case of device files.
109 static umode_t p9mode2unixmode(struct v9fs_session_info *v9ses,
110 struct p9_wstat *stat, dev_t *rdev)
113 u32 mode = stat->mode;
116 res = p9mode2perm(v9ses, stat);
118 if ((mode & P9_DMDIR) == P9_DMDIR)
120 else if ((mode & P9_DMSYMLINK) && (v9fs_proto_dotu(v9ses)))
122 else if ((mode & P9_DMSOCKET) && (v9fs_proto_dotu(v9ses))
123 && (v9ses->nodev == 0))
125 else if ((mode & P9_DMNAMEDPIPE) && (v9fs_proto_dotu(v9ses))
126 && (v9ses->nodev == 0))
128 else if ((mode & P9_DMDEVICE) && (v9fs_proto_dotu(v9ses))
129 && (v9ses->nodev == 0)) {
131 int major = -1, minor = -1;
133 r = sscanf(stat->extension, "%c %i %i", &type, &major, &minor);
135 p9_debug(P9_DEBUG_ERROR,
136 "invalid device string, umode will be bogus: %s\n",
148 p9_debug(P9_DEBUG_ERROR, "Unknown special type %c %s\n",
149 type, stat->extension);
151 *rdev = MKDEV(major, minor);
159 * v9fs_uflags2omode- convert posix open flags to plan 9 mode bits
160 * @uflags: flags to convert
161 * @extended: if .u extensions are active
164 int v9fs_uflags2omode(int uflags, int extended)
188 if (uflags & O_APPEND)
196 * v9fs_blank_wstat - helper function to setup a 9P stat structure
197 * @wstat: structure to initialize
202 v9fs_blank_wstat(struct p9_wstat *wstat)
206 wstat->qid.type = ~0;
207 wstat->qid.version = ~0;
208 *((long long *)&wstat->qid.path) = ~0;
217 wstat->n_uid = INVALID_UID;
218 wstat->n_gid = INVALID_GID;
219 wstat->n_muid = INVALID_UID;
220 wstat->extension = NULL;
224 * v9fs_alloc_inode - helper function to allocate an inode
225 * @sb: The superblock to allocate the inode from
227 struct inode *v9fs_alloc_inode(struct super_block *sb)
229 struct v9fs_inode *v9inode;
231 v9inode = kmem_cache_alloc(v9fs_inode_cache, GFP_KERNEL);
234 #ifdef CONFIG_9P_FSCACHE
235 v9inode->fscache = NULL;
237 v9inode->writeback_fid = NULL;
238 v9inode->cache_validity = 0;
239 mutex_init(&v9inode->v_mutex);
240 return &v9inode->vfs_inode;
244 * v9fs_free_inode - destroy an inode
245 * @inode: The inode to be freed
248 void v9fs_free_inode(struct inode *inode)
250 kmem_cache_free(v9fs_inode_cache, V9FS_I(inode));
253 int v9fs_init_inode(struct v9fs_session_info *v9ses,
254 struct inode *inode, umode_t mode, dev_t rdev)
258 inode_init_owner(&init_user_ns, inode, NULL, mode);
260 inode->i_rdev = rdev;
261 inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
262 inode->i_mapping->a_ops = &v9fs_addr_operations;
263 inode->i_private = NULL;
265 switch (mode & S_IFMT) {
270 if (v9fs_proto_dotl(v9ses)) {
271 inode->i_op = &v9fs_file_inode_operations_dotl;
272 } else if (v9fs_proto_dotu(v9ses)) {
273 inode->i_op = &v9fs_file_inode_operations;
275 p9_debug(P9_DEBUG_ERROR,
276 "special files without extended mode\n");
280 init_special_inode(inode, inode->i_mode, inode->i_rdev);
283 if (v9fs_proto_dotl(v9ses)) {
284 inode->i_op = &v9fs_file_inode_operations_dotl;
285 if (v9ses->cache == CACHE_LOOSE ||
286 v9ses->cache == CACHE_FSCACHE)
288 &v9fs_cached_file_operations_dotl;
289 else if (v9ses->cache == CACHE_MMAP)
290 inode->i_fop = &v9fs_mmap_file_operations_dotl;
292 inode->i_fop = &v9fs_file_operations_dotl;
294 inode->i_op = &v9fs_file_inode_operations;
295 if (v9ses->cache == CACHE_LOOSE ||
296 v9ses->cache == CACHE_FSCACHE)
298 &v9fs_cached_file_operations;
299 else if (v9ses->cache == CACHE_MMAP)
300 inode->i_fop = &v9fs_mmap_file_operations;
302 inode->i_fop = &v9fs_file_operations;
307 if (!v9fs_proto_dotu(v9ses) && !v9fs_proto_dotl(v9ses)) {
308 p9_debug(P9_DEBUG_ERROR,
309 "extended modes used with legacy protocol\n");
314 if (v9fs_proto_dotl(v9ses))
315 inode->i_op = &v9fs_symlink_inode_operations_dotl;
317 inode->i_op = &v9fs_symlink_inode_operations;
322 if (v9fs_proto_dotl(v9ses))
323 inode->i_op = &v9fs_dir_inode_operations_dotl;
324 else if (v9fs_proto_dotu(v9ses))
325 inode->i_op = &v9fs_dir_inode_operations_dotu;
327 inode->i_op = &v9fs_dir_inode_operations;
329 if (v9fs_proto_dotl(v9ses))
330 inode->i_fop = &v9fs_dir_operations_dotl;
332 inode->i_fop = &v9fs_dir_operations;
336 p9_debug(P9_DEBUG_ERROR, "BAD mode 0x%hx S_IFMT 0x%x\n",
337 mode, mode & S_IFMT);
347 * v9fs_get_inode - helper function to setup an inode
349 * @mode: mode to setup inode with
350 * @rdev: The device numbers to set
353 struct inode *v9fs_get_inode(struct super_block *sb, umode_t mode, dev_t rdev)
357 struct v9fs_session_info *v9ses = sb->s_fs_info;
359 p9_debug(P9_DEBUG_VFS, "super block: %p mode: %ho\n", sb, mode);
361 inode = new_inode(sb);
363 pr_warn("%s (%d): Problem allocating inode\n",
364 __func__, task_pid_nr(current));
365 return ERR_PTR(-ENOMEM);
367 err = v9fs_init_inode(v9ses, inode, mode, rdev);
376 * v9fs_evict_inode - Remove an inode from the inode cache
377 * @inode: inode to release
380 void v9fs_evict_inode(struct inode *inode)
382 struct v9fs_inode *v9inode = V9FS_I(inode);
385 truncate_inode_pages_final(&inode->i_data);
386 version = cpu_to_le32(v9inode->qid.version);
387 fscache_clear_inode_writeback(v9fs_inode_cookie(v9inode), inode,
390 filemap_fdatawrite(&inode->i_data);
392 fscache_relinquish_cookie(v9fs_inode_cookie(v9inode), false);
393 /* clunk the fid stashed in writeback_fid */
394 if (v9inode->writeback_fid) {
395 p9_client_clunk(v9inode->writeback_fid);
396 v9inode->writeback_fid = NULL;
400 static int v9fs_test_inode(struct inode *inode, void *data)
404 struct v9fs_inode *v9inode = V9FS_I(inode);
405 struct p9_wstat *st = (struct p9_wstat *)data;
406 struct v9fs_session_info *v9ses = v9fs_inode2v9ses(inode);
408 umode = p9mode2unixmode(v9ses, st, &rdev);
409 /* don't match inode of different type */
410 if (inode_wrong_type(inode, umode))
413 /* compare qid details */
414 if (memcmp(&v9inode->qid.version,
415 &st->qid.version, sizeof(v9inode->qid.version)))
418 if (v9inode->qid.type != st->qid.type)
421 if (v9inode->qid.path != st->qid.path)
426 static int v9fs_test_new_inode(struct inode *inode, void *data)
431 static int v9fs_set_inode(struct inode *inode, void *data)
433 struct v9fs_inode *v9inode = V9FS_I(inode);
434 struct p9_wstat *st = (struct p9_wstat *)data;
436 memcpy(&v9inode->qid, &st->qid, sizeof(st->qid));
440 static struct inode *v9fs_qid_iget(struct super_block *sb,
450 struct v9fs_session_info *v9ses = sb->s_fs_info;
451 int (*test)(struct inode *inode, void *data);
454 test = v9fs_test_new_inode;
456 test = v9fs_test_inode;
458 i_ino = v9fs_qid2ino(qid);
459 inode = iget5_locked(sb, i_ino, test, v9fs_set_inode, st);
461 return ERR_PTR(-ENOMEM);
462 if (!(inode->i_state & I_NEW))
465 * initialize the inode with the stat info
466 * FIXME!! we may need support for stale inodes
469 inode->i_ino = i_ino;
470 umode = p9mode2unixmode(v9ses, st, &rdev);
471 retval = v9fs_init_inode(v9ses, inode, umode, rdev);
475 v9fs_stat2inode(st, inode, sb, 0);
476 v9fs_cache_inode_get_cookie(inode);
477 unlock_new_inode(inode);
481 return ERR_PTR(retval);
486 v9fs_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid,
487 struct super_block *sb, int new)
490 struct inode *inode = NULL;
492 st = p9_client_stat(fid);
496 inode = v9fs_qid_iget(sb, &st->qid, st, new);
503 * v9fs_at_to_dotl_flags- convert Linux specific AT flags to
505 * @flags: flags to convert
507 static int v9fs_at_to_dotl_flags(int flags)
511 if (flags & AT_REMOVEDIR)
512 rflags |= P9_DOTL_AT_REMOVEDIR;
518 * v9fs_dec_count - helper functon to drop i_nlink.
520 * If a directory had nlink <= 2 (including . and ..), then we should not drop
521 * the link count, which indicates the underlying exported fs doesn't maintain
522 * nlink accurately. e.g.
523 * - overlayfs sets nlink to 1 for merged dir
524 * - ext4 (with dir_nlink feature enabled) sets nlink to 1 if a dir has more
525 * than EXT4_LINK_MAX (65000) links.
527 * @inode: inode whose nlink is being dropped
529 static void v9fs_dec_count(struct inode *inode)
531 if (!S_ISDIR(inode->i_mode) || inode->i_nlink > 2)
536 * v9fs_remove - helper function to remove files and directories
537 * @dir: directory inode that is being deleted
538 * @dentry: dentry that is being deleted
539 * @flags: removing a directory
543 static int v9fs_remove(struct inode *dir, struct dentry *dentry, int flags)
546 int retval = -EOPNOTSUPP;
547 struct p9_fid *v9fid, *dfid;
548 struct v9fs_session_info *v9ses;
550 p9_debug(P9_DEBUG_VFS, "inode: %p dentry: %p rmdir: %x\n",
553 v9ses = v9fs_inode2v9ses(dir);
554 inode = d_inode(dentry);
555 dfid = v9fs_parent_fid(dentry);
557 retval = PTR_ERR(dfid);
558 p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", retval);
561 if (v9fs_proto_dotl(v9ses))
562 retval = p9_client_unlinkat(dfid, dentry->d_name.name,
563 v9fs_at_to_dotl_flags(flags));
564 p9_client_clunk(dfid);
565 if (retval == -EOPNOTSUPP) {
566 /* Try the one based on path */
567 v9fid = v9fs_fid_clone(dentry);
569 return PTR_ERR(v9fid);
570 retval = p9_client_remove(v9fid);
574 * directories on unlink should have zero
577 if (flags & AT_REMOVEDIR) {
581 v9fs_dec_count(inode);
583 v9fs_invalidate_inode_attr(inode);
584 v9fs_invalidate_inode_attr(dir);
586 /* invalidate all fids associated with dentry */
587 /* NOTE: This will not include open fids */
588 dentry->d_op->d_release(dentry);
594 * v9fs_create - Create a file
595 * @v9ses: session information
596 * @dir: directory that dentry is being created in
597 * @dentry: dentry that is being created
598 * @extension: 9p2000.u extension string to support devices, etc.
599 * @perm: create permissions
603 static struct p9_fid *
604 v9fs_create(struct v9fs_session_info *v9ses, struct inode *dir,
605 struct dentry *dentry, char *extension, u32 perm, u8 mode)
608 const unsigned char *name;
609 struct p9_fid *dfid, *ofid = NULL, *fid = NULL;
612 p9_debug(P9_DEBUG_VFS, "name %pd\n", dentry);
615 name = dentry->d_name.name;
616 dfid = v9fs_parent_fid(dentry);
619 p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
623 /* clone a fid to use for creation */
624 ofid = clone_fid(dfid);
627 p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
628 p9_client_clunk(dfid);
632 err = p9_client_fcreate(ofid, name, perm, mode, extension);
634 p9_debug(P9_DEBUG_VFS, "p9_client_fcreate failed %d\n", err);
635 p9_client_clunk(dfid);
639 if (!(perm & P9_DMLINK)) {
640 /* now walk from the parent so we can get unopened fid */
641 fid = p9_client_walk(dfid, 1, &name, 1);
644 p9_debug(P9_DEBUG_VFS,
645 "p9_client_walk failed %d\n", err);
647 p9_client_clunk(dfid);
651 * instantiate inode and assign the unopened fid to the dentry
653 inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
655 err = PTR_ERR(inode);
656 p9_debug(P9_DEBUG_VFS,
657 "inode creation failed %d\n", err);
658 p9_client_clunk(dfid);
661 v9fs_fid_add(dentry, fid);
662 d_instantiate(dentry, inode);
664 p9_client_clunk(dfid);
668 p9_client_clunk(ofid);
671 p9_client_clunk(fid);
677 * v9fs_vfs_create - VFS hook to create a regular file
678 * @mnt_userns: The user namespace of the mount
679 * @dir: The parent directory
680 * @dentry: The name of file to be created
681 * @mode: The UNIX file mode to set
682 * @excl: True if the file must not yet exist
684 * open(.., O_CREAT) is handled in v9fs_vfs_atomic_open(). This is only called
690 v9fs_vfs_create(struct user_namespace *mnt_userns, struct inode *dir,
691 struct dentry *dentry, umode_t mode, bool excl)
693 struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dir);
694 u32 perm = unixmode2p9mode(v9ses, mode);
698 fid = v9fs_create(v9ses, dir, dentry, NULL, perm, P9_ORDWR);
702 v9fs_invalidate_inode_attr(dir);
703 p9_client_clunk(fid);
709 * v9fs_vfs_mkdir - VFS mkdir hook to create a directory
710 * @mnt_userns: The user namespace of the mount
711 * @dir: inode that is being unlinked
712 * @dentry: dentry that is being unlinked
713 * @mode: mode for new directory
717 static int v9fs_vfs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
718 struct dentry *dentry, umode_t mode)
723 struct v9fs_session_info *v9ses;
725 p9_debug(P9_DEBUG_VFS, "name %pd\n", dentry);
727 v9ses = v9fs_inode2v9ses(dir);
728 perm = unixmode2p9mode(v9ses, mode | S_IFDIR);
729 fid = v9fs_create(v9ses, dir, dentry, NULL, perm, P9_OREAD);
735 v9fs_invalidate_inode_attr(dir);
739 p9_client_clunk(fid);
745 * v9fs_vfs_lookup - VFS lookup hook to "walk" to a new inode
746 * @dir: inode that is being walked from
747 * @dentry: dentry that is being walked to?
748 * @flags: lookup flags (unused)
752 struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
756 struct v9fs_session_info *v9ses;
757 struct p9_fid *dfid, *fid;
759 const unsigned char *name;
761 p9_debug(P9_DEBUG_VFS, "dir: %p dentry: (%pd) %p flags: %x\n",
762 dir, dentry, dentry, flags);
764 if (dentry->d_name.len > NAME_MAX)
765 return ERR_PTR(-ENAMETOOLONG);
767 v9ses = v9fs_inode2v9ses(dir);
768 /* We can walk d_parent because we hold the dir->i_mutex */
769 dfid = v9fs_parent_fid(dentry);
771 return ERR_CAST(dfid);
774 * Make sure we don't use a wrong inode due to parallel
775 * unlink. For cached mode create calls request for new
776 * inode. But with cache disabled, lookup should do this.
778 name = dentry->d_name.name;
779 fid = p9_client_walk(dfid, 1, &name, 1);
780 p9_client_clunk(dfid);
781 if (fid == ERR_PTR(-ENOENT))
783 else if (IS_ERR(fid))
784 inode = ERR_CAST(fid);
785 else if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
786 inode = v9fs_get_inode_from_fid(v9ses, fid, dir->i_sb);
788 inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
790 * If we had a rename on the server and a parallel lookup
791 * for the new name, then make sure we instantiate with
792 * the new name. ie look up for a/b, while on server somebody
793 * moved b under k and client parallely did a lookup for
796 res = d_splice_alias(inode, dentry);
799 v9fs_fid_add(dentry, fid);
800 else if (!IS_ERR(res))
801 v9fs_fid_add(res, fid);
803 p9_client_clunk(fid);
809 v9fs_vfs_atomic_open(struct inode *dir, struct dentry *dentry,
810 struct file *file, unsigned int flags, umode_t mode)
814 struct v9fs_inode *v9inode;
815 struct v9fs_session_info *v9ses;
816 struct p9_fid *fid, *inode_fid;
817 struct dentry *res = NULL;
820 if (d_in_lookup(dentry)) {
821 res = v9fs_vfs_lookup(dir, dentry, 0);
830 if (!(flags & O_CREAT) || d_really_is_positive(dentry))
831 return finish_no_open(file, res);
835 v9ses = v9fs_inode2v9ses(dir);
836 perm = unixmode2p9mode(v9ses, mode);
837 fid = v9fs_create(v9ses, dir, dentry, NULL, perm,
838 v9fs_uflags2omode(flags,
839 v9fs_proto_dotu(v9ses)));
846 v9fs_invalidate_inode_attr(dir);
847 inode = d_inode(dentry);
848 v9inode = V9FS_I(inode);
849 mutex_lock(&v9inode->v_mutex);
850 if ((v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) &&
851 !v9inode->writeback_fid &&
852 ((flags & O_ACCMODE) != O_RDONLY)) {
854 * clone a fid and add it to writeback_fid
855 * we do it during open time instead of
856 * page dirty time via write_begin/page_mkwrite
857 * because we want write after unlink usecase
860 inode_fid = v9fs_writeback_fid(dentry);
861 if (IS_ERR(inode_fid)) {
862 err = PTR_ERR(inode_fid);
863 mutex_unlock(&v9inode->v_mutex);
866 v9inode->writeback_fid = (void *) inode_fid;
868 mutex_unlock(&v9inode->v_mutex);
869 err = finish_open(file, dentry, generic_file_open);
873 file->private_data = fid;
874 if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
875 fscache_use_cookie(v9fs_inode_cookie(v9inode),
876 file->f_mode & FMODE_WRITE);
877 v9fs_open_fid_add(inode, fid);
879 file->f_mode |= FMODE_CREATED;
886 p9_client_clunk(fid);
891 * v9fs_vfs_unlink - VFS unlink hook to delete an inode
892 * @i: inode that is being unlinked
893 * @d: dentry that is being unlinked
897 int v9fs_vfs_unlink(struct inode *i, struct dentry *d)
899 return v9fs_remove(i, d, 0);
903 * v9fs_vfs_rmdir - VFS unlink hook to delete a directory
904 * @i: inode that is being unlinked
905 * @d: dentry that is being unlinked
909 int v9fs_vfs_rmdir(struct inode *i, struct dentry *d)
911 return v9fs_remove(i, d, AT_REMOVEDIR);
915 * v9fs_vfs_rename - VFS hook to rename an inode
916 * @mnt_userns: The user namespace of the mount
917 * @old_dir: old dir inode
918 * @old_dentry: old dentry
919 * @new_dir: new dir inode
920 * @new_dentry: new dentry
921 * @flags: RENAME_* flags
926 v9fs_vfs_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
927 struct dentry *old_dentry, struct inode *new_dir,
928 struct dentry *new_dentry, unsigned int flags)
931 struct inode *old_inode;
932 struct inode *new_inode;
933 struct v9fs_session_info *v9ses;
934 struct p9_fid *oldfid, *dfid;
935 struct p9_fid *olddirfid;
936 struct p9_fid *newdirfid;
937 struct p9_wstat wstat;
942 p9_debug(P9_DEBUG_VFS, "\n");
944 old_inode = d_inode(old_dentry);
945 new_inode = d_inode(new_dentry);
946 v9ses = v9fs_inode2v9ses(old_inode);
947 oldfid = v9fs_fid_lookup(old_dentry);
949 return PTR_ERR(oldfid);
951 dfid = v9fs_parent_fid(old_dentry);
952 olddirfid = clone_fid(dfid);
953 if (dfid && !IS_ERR(dfid))
954 p9_client_clunk(dfid);
956 if (IS_ERR(olddirfid)) {
957 retval = PTR_ERR(olddirfid);
961 dfid = v9fs_parent_fid(new_dentry);
962 newdirfid = clone_fid(dfid);
963 p9_client_clunk(dfid);
965 if (IS_ERR(newdirfid)) {
966 retval = PTR_ERR(newdirfid);
970 down_write(&v9ses->rename_sem);
971 if (v9fs_proto_dotl(v9ses)) {
972 retval = p9_client_renameat(olddirfid, old_dentry->d_name.name,
973 newdirfid, new_dentry->d_name.name);
974 if (retval == -EOPNOTSUPP)
975 retval = p9_client_rename(oldfid, newdirfid,
976 new_dentry->d_name.name);
977 if (retval != -EOPNOTSUPP)
980 if (old_dentry->d_parent != new_dentry->d_parent) {
982 * 9P .u can only handle file rename in the same directory
985 p9_debug(P9_DEBUG_ERROR, "old dir and new dir are different\n");
989 v9fs_blank_wstat(&wstat);
990 wstat.muid = v9ses->uname;
991 wstat.name = new_dentry->d_name.name;
992 retval = p9_client_wstat(oldfid, &wstat);
997 if (S_ISDIR(new_inode->i_mode))
998 clear_nlink(new_inode);
1000 v9fs_dec_count(new_inode);
1002 if (S_ISDIR(old_inode->i_mode)) {
1005 v9fs_dec_count(old_dir);
1007 v9fs_invalidate_inode_attr(old_inode);
1008 v9fs_invalidate_inode_attr(old_dir);
1009 v9fs_invalidate_inode_attr(new_dir);
1011 /* successful rename */
1012 d_move(old_dentry, new_dentry);
1014 up_write(&v9ses->rename_sem);
1015 p9_client_clunk(newdirfid);
1018 p9_client_clunk(olddirfid);
1021 p9_client_clunk(oldfid);
1026 * v9fs_vfs_getattr - retrieve file metadata
1027 * @mnt_userns: The user namespace of the mount
1028 * @path: Object to query
1029 * @stat: metadata structure to populate
1030 * @request_mask: Mask of STATX_xxx flags indicating the caller's interests
1031 * @flags: AT_STATX_xxx setting
1036 v9fs_vfs_getattr(struct user_namespace *mnt_userns, const struct path *path,
1037 struct kstat *stat, u32 request_mask, unsigned int flags)
1039 struct dentry *dentry = path->dentry;
1040 struct v9fs_session_info *v9ses;
1042 struct p9_wstat *st;
1044 p9_debug(P9_DEBUG_VFS, "dentry: %p\n", dentry);
1045 v9ses = v9fs_dentry2v9ses(dentry);
1046 if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
1047 generic_fillattr(&init_user_ns, d_inode(dentry), stat);
1050 fid = v9fs_fid_lookup(dentry);
1052 return PTR_ERR(fid);
1054 st = p9_client_stat(fid);
1055 p9_client_clunk(fid);
1059 v9fs_stat2inode(st, d_inode(dentry), dentry->d_sb, 0);
1060 generic_fillattr(&init_user_ns, d_inode(dentry), stat);
1068 * v9fs_vfs_setattr - set file metadata
1069 * @mnt_userns: The user namespace of the mount
1070 * @dentry: file whose metadata to set
1071 * @iattr: metadata assignment structure
1075 static int v9fs_vfs_setattr(struct user_namespace *mnt_userns,
1076 struct dentry *dentry, struct iattr *iattr)
1078 int retval, use_dentry = 0;
1079 struct inode *inode = d_inode(dentry);
1080 struct v9fs_inode *v9inode = V9FS_I(inode);
1081 struct v9fs_session_info *v9ses;
1082 struct p9_fid *fid = NULL;
1083 struct p9_wstat wstat;
1085 p9_debug(P9_DEBUG_VFS, "\n");
1086 retval = setattr_prepare(&init_user_ns, dentry, iattr);
1091 v9ses = v9fs_dentry2v9ses(dentry);
1092 if (iattr->ia_valid & ATTR_FILE) {
1093 fid = iattr->ia_file->private_data;
1097 fid = v9fs_fid_lookup(dentry);
1101 return PTR_ERR(fid);
1103 v9fs_blank_wstat(&wstat);
1104 if (iattr->ia_valid & ATTR_MODE)
1105 wstat.mode = unixmode2p9mode(v9ses, iattr->ia_mode);
1107 if (iattr->ia_valid & ATTR_MTIME)
1108 wstat.mtime = iattr->ia_mtime.tv_sec;
1110 if (iattr->ia_valid & ATTR_ATIME)
1111 wstat.atime = iattr->ia_atime.tv_sec;
1113 if (iattr->ia_valid & ATTR_SIZE)
1114 wstat.length = iattr->ia_size;
1116 if (v9fs_proto_dotu(v9ses)) {
1117 if (iattr->ia_valid & ATTR_UID)
1118 wstat.n_uid = iattr->ia_uid;
1120 if (iattr->ia_valid & ATTR_GID)
1121 wstat.n_gid = iattr->ia_gid;
1124 /* Write all dirty data */
1125 if (d_is_reg(dentry))
1126 filemap_write_and_wait(inode->i_mapping);
1128 retval = p9_client_wstat(fid, &wstat);
1131 p9_client_clunk(fid);
1136 if ((iattr->ia_valid & ATTR_SIZE) &&
1137 iattr->ia_size != i_size_read(inode)) {
1138 truncate_setsize(inode, iattr->ia_size);
1139 fscache_resize_cookie(v9fs_inode_cookie(v9inode), iattr->ia_size);
1142 v9fs_invalidate_inode_attr(inode);
1144 setattr_copy(&init_user_ns, inode, iattr);
1145 mark_inode_dirty(inode);
1150 * v9fs_stat2inode - populate an inode structure with mistat info
1151 * @stat: Plan 9 metadata (mistat) structure
1152 * @inode: inode to populate
1153 * @sb: superblock of filesystem
1154 * @flags: control flags (e.g. V9FS_STAT2INODE_KEEP_ISIZE)
1159 v9fs_stat2inode(struct p9_wstat *stat, struct inode *inode,
1160 struct super_block *sb, unsigned int flags)
1163 struct v9fs_session_info *v9ses = sb->s_fs_info;
1164 struct v9fs_inode *v9inode = V9FS_I(inode);
1166 set_nlink(inode, 1);
1168 inode->i_atime.tv_sec = stat->atime;
1169 inode->i_mtime.tv_sec = stat->mtime;
1170 inode->i_ctime.tv_sec = stat->mtime;
1172 inode->i_uid = v9ses->dfltuid;
1173 inode->i_gid = v9ses->dfltgid;
1175 if (v9fs_proto_dotu(v9ses)) {
1176 inode->i_uid = stat->n_uid;
1177 inode->i_gid = stat->n_gid;
1179 if ((S_ISREG(inode->i_mode)) || (S_ISDIR(inode->i_mode))) {
1180 if (v9fs_proto_dotu(v9ses)) {
1181 unsigned int i_nlink;
1183 * Hadlink support got added later to the .u extension.
1184 * So there can be a server out there that doesn't
1185 * support this even with .u extension. That would
1186 * just leave us with stat->extension being an empty
1189 /* HARDLINKCOUNT %u */
1190 if (sscanf(stat->extension,
1191 " HARDLINKCOUNT %u", &i_nlink) == 1)
1192 set_nlink(inode, i_nlink);
1195 mode = p9mode2perm(v9ses, stat);
1196 mode |= inode->i_mode & ~S_IALLUGO;
1197 inode->i_mode = mode;
1199 if (!(flags & V9FS_STAT2INODE_KEEP_ISIZE))
1200 v9fs_i_size_write(inode, stat->length);
1201 /* not real number of blocks, but 512 byte ones ... */
1202 inode->i_blocks = (stat->length + 512 - 1) >> 9;
1203 v9inode->cache_validity &= ~V9FS_INO_INVALID_ATTR;
1207 * v9fs_qid2ino - convert qid into inode number
1210 * BUG: potential for inode number collisions?
1213 ino_t v9fs_qid2ino(struct p9_qid *qid)
1215 u64 path = qid->path + 2;
1218 if (sizeof(ino_t) == sizeof(path))
1219 memcpy(&i, &path, sizeof(ino_t));
1221 i = (ino_t) (path ^ (path >> 32));
1227 * v9fs_vfs_get_link - follow a symlink path
1228 * @dentry: dentry for symlink
1229 * @inode: inode for symlink
1230 * @done: delayed call for when we are done with the return value
1233 static const char *v9fs_vfs_get_link(struct dentry *dentry,
1234 struct inode *inode,
1235 struct delayed_call *done)
1237 struct v9fs_session_info *v9ses;
1239 struct p9_wstat *st;
1243 return ERR_PTR(-ECHILD);
1245 v9ses = v9fs_dentry2v9ses(dentry);
1246 fid = v9fs_fid_lookup(dentry);
1247 p9_debug(P9_DEBUG_VFS, "%pd\n", dentry);
1250 return ERR_CAST(fid);
1252 if (!v9fs_proto_dotu(v9ses))
1253 return ERR_PTR(-EBADF);
1255 st = p9_client_stat(fid);
1256 p9_client_clunk(fid);
1258 return ERR_CAST(st);
1260 if (!(st->mode & P9_DMSYMLINK)) {
1263 return ERR_PTR(-EINVAL);
1265 res = st->extension;
1266 st->extension = NULL;
1267 if (strlen(res) >= PATH_MAX)
1268 res[PATH_MAX - 1] = '\0';
1272 set_delayed_call(done, kfree_link, res);
1277 * v9fs_vfs_mkspecial - create a special file
1278 * @dir: inode to create special file in
1279 * @dentry: dentry to create
1280 * @perm: mode to create special file
1281 * @extension: 9p2000.u format extension string representing special file
1285 static int v9fs_vfs_mkspecial(struct inode *dir, struct dentry *dentry,
1286 u32 perm, const char *extension)
1289 struct v9fs_session_info *v9ses;
1291 v9ses = v9fs_inode2v9ses(dir);
1292 if (!v9fs_proto_dotu(v9ses)) {
1293 p9_debug(P9_DEBUG_ERROR, "not extended\n");
1297 fid = v9fs_create(v9ses, dir, dentry, (char *) extension, perm,
1300 return PTR_ERR(fid);
1302 v9fs_invalidate_inode_attr(dir);
1303 p9_client_clunk(fid);
1308 * v9fs_vfs_symlink - helper function to create symlinks
1309 * @mnt_userns: The user namespace of the mount
1310 * @dir: directory inode containing symlink
1311 * @dentry: dentry for symlink
1312 * @symname: symlink data
1314 * See Also: 9P2000.u RFC for more information
1319 v9fs_vfs_symlink(struct user_namespace *mnt_userns, struct inode *dir,
1320 struct dentry *dentry, const char *symname)
1322 p9_debug(P9_DEBUG_VFS, " %lu,%pd,%s\n",
1323 dir->i_ino, dentry, symname);
1325 return v9fs_vfs_mkspecial(dir, dentry, P9_DMSYMLINK, symname);
1328 #define U32_MAX_DIGITS 10
1331 * v9fs_vfs_link - create a hardlink
1332 * @old_dentry: dentry for file to link to
1333 * @dir: inode destination for new link
1334 * @dentry: dentry for link
1339 v9fs_vfs_link(struct dentry *old_dentry, struct inode *dir,
1340 struct dentry *dentry)
1343 char name[1 + U32_MAX_DIGITS + 2]; /* sign + number + \n + \0 */
1344 struct p9_fid *oldfid;
1346 p9_debug(P9_DEBUG_VFS, " %lu,%pd,%pd\n",
1347 dir->i_ino, dentry, old_dentry);
1349 oldfid = v9fs_fid_clone(old_dentry);
1351 return PTR_ERR(oldfid);
1353 sprintf(name, "%d\n", oldfid->fid);
1354 retval = v9fs_vfs_mkspecial(dir, dentry, P9_DMLINK, name);
1356 v9fs_refresh_inode(oldfid, d_inode(old_dentry));
1357 v9fs_invalidate_inode_attr(dir);
1359 p9_client_clunk(oldfid);
1364 * v9fs_vfs_mknod - create a special file
1365 * @mnt_userns: The user namespace of the mount
1366 * @dir: inode destination for new link
1367 * @dentry: dentry for file
1368 * @mode: mode for creation
1369 * @rdev: device associated with special file
1374 v9fs_vfs_mknod(struct user_namespace *mnt_userns, struct inode *dir,
1375 struct dentry *dentry, umode_t mode, dev_t rdev)
1377 struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dir);
1379 char name[2 + U32_MAX_DIGITS + 1 + U32_MAX_DIGITS + 1];
1382 p9_debug(P9_DEBUG_VFS, " %lu,%pd mode: %x MAJOR: %u MINOR: %u\n",
1383 dir->i_ino, dentry, mode,
1384 MAJOR(rdev), MINOR(rdev));
1386 /* build extension */
1388 sprintf(name, "b %u %u", MAJOR(rdev), MINOR(rdev));
1389 else if (S_ISCHR(mode))
1390 sprintf(name, "c %u %u", MAJOR(rdev), MINOR(rdev));
1394 perm = unixmode2p9mode(v9ses, mode);
1395 retval = v9fs_vfs_mkspecial(dir, dentry, perm, name);
1400 int v9fs_refresh_inode(struct p9_fid *fid, struct inode *inode)
1404 struct p9_wstat *st;
1405 struct v9fs_session_info *v9ses;
1408 v9ses = v9fs_inode2v9ses(inode);
1409 st = p9_client_stat(fid);
1413 * Don't update inode if the file type is different
1415 umode = p9mode2unixmode(v9ses, st, &rdev);
1416 if (inode_wrong_type(inode, umode))
1420 * We don't want to refresh inode->i_size,
1421 * because we may have cached data
1423 flags = (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) ?
1424 V9FS_STAT2INODE_KEEP_ISIZE : 0;
1425 v9fs_stat2inode(st, inode, inode->i_sb, flags);
1432 static const struct inode_operations v9fs_dir_inode_operations_dotu = {
1433 .create = v9fs_vfs_create,
1434 .lookup = v9fs_vfs_lookup,
1435 .atomic_open = v9fs_vfs_atomic_open,
1436 .symlink = v9fs_vfs_symlink,
1437 .link = v9fs_vfs_link,
1438 .unlink = v9fs_vfs_unlink,
1439 .mkdir = v9fs_vfs_mkdir,
1440 .rmdir = v9fs_vfs_rmdir,
1441 .mknod = v9fs_vfs_mknod,
1442 .rename = v9fs_vfs_rename,
1443 .getattr = v9fs_vfs_getattr,
1444 .setattr = v9fs_vfs_setattr,
1447 static const struct inode_operations v9fs_dir_inode_operations = {
1448 .create = v9fs_vfs_create,
1449 .lookup = v9fs_vfs_lookup,
1450 .atomic_open = v9fs_vfs_atomic_open,
1451 .unlink = v9fs_vfs_unlink,
1452 .mkdir = v9fs_vfs_mkdir,
1453 .rmdir = v9fs_vfs_rmdir,
1454 .mknod = v9fs_vfs_mknod,
1455 .rename = v9fs_vfs_rename,
1456 .getattr = v9fs_vfs_getattr,
1457 .setattr = v9fs_vfs_setattr,
1460 static const struct inode_operations v9fs_file_inode_operations = {
1461 .getattr = v9fs_vfs_getattr,
1462 .setattr = v9fs_vfs_setattr,
1465 static const struct inode_operations v9fs_symlink_inode_operations = {
1466 .get_link = v9fs_vfs_get_link,
1467 .getattr = v9fs_vfs_getattr,
1468 .setattr = v9fs_vfs_setattr,