2 * linux/fs/9p/vfs_inode.c
4 * This file contains vfs inode ops for the 9P2000 protocol.
6 * Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
7 * Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2
11 * as published by the Free Software Foundation.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to:
20 * Free Software Foundation
21 * 51 Franklin Street, Fifth Floor
22 * Boston, MA 02111-1301 USA
26 #include <linux/module.h>
27 #include <linux/errno.h>
29 #include <linux/file.h>
30 #include <linux/pagemap.h>
31 #include <linux/stat.h>
32 #include <linux/string.h>
33 #include <linux/inet.h>
34 #include <linux/namei.h>
35 #include <linux/idr.h>
36 #include <linux/sched.h>
37 #include <linux/slab.h>
38 #include <linux/xattr.h>
39 #include <linux/posix_acl.h>
40 #include <net/9p/9p.h>
41 #include <net/9p/client.h>
50 static const struct inode_operations v9fs_dir_inode_operations;
51 static const struct inode_operations v9fs_dir_inode_operations_dotu;
52 static const struct inode_operations v9fs_file_inode_operations;
53 static const struct inode_operations v9fs_symlink_inode_operations;
56 * unixmode2p9mode - convert unix mode bits to plan 9
57 * @v9ses: v9fs session information
58 * @mode: mode to convert
62 static int unixmode2p9mode(struct v9fs_session_info *v9ses, int mode)
68 if (v9fs_proto_dotu(v9ses)) {
71 if (v9ses->nodev == 0) {
75 res |= P9_DMNAMEDPIPE;
82 if ((mode & S_ISUID) == S_ISUID)
84 if ((mode & S_ISGID) == S_ISGID)
86 if ((mode & S_ISVTX) == S_ISVTX)
88 if ((mode & P9_DMLINK))
96 * p9mode2unixmode- convert plan9 mode bits to unix mode bits
97 * @v9ses: v9fs session information
98 * @mode: mode to convert
102 static int p9mode2unixmode(struct v9fs_session_info *v9ses, int mode)
108 if ((mode & P9_DMDIR) == P9_DMDIR)
110 else if ((mode & P9_DMSYMLINK) && (v9fs_proto_dotu(v9ses)))
112 else if ((mode & P9_DMSOCKET) && (v9fs_proto_dotu(v9ses))
113 && (v9ses->nodev == 0))
115 else if ((mode & P9_DMNAMEDPIPE) && (v9fs_proto_dotu(v9ses))
116 && (v9ses->nodev == 0))
118 else if ((mode & P9_DMDEVICE) && (v9fs_proto_dotu(v9ses))
119 && (v9ses->nodev == 0))
124 if (v9fs_proto_dotu(v9ses)) {
125 if ((mode & P9_DMSETUID) == P9_DMSETUID)
128 if ((mode & P9_DMSETGID) == P9_DMSETGID)
131 if ((mode & P9_DMSETVTX) == P9_DMSETVTX)
139 * v9fs_uflags2omode- convert posix open flags to plan 9 mode bits
140 * @uflags: flags to convert
141 * @extended: if .u extensions are active
144 int v9fs_uflags2omode(int uflags, int extended)
164 if (uflags & O_TRUNC)
171 if (uflags & O_APPEND)
179 * v9fs_blank_wstat - helper function to setup a 9P stat structure
180 * @wstat: structure to initialize
185 v9fs_blank_wstat(struct p9_wstat *wstat)
189 wstat->qid.type = ~0;
190 wstat->qid.version = ~0;
191 *((long long *)&wstat->qid.path) = ~0;
203 wstat->extension = NULL;
206 #ifdef CONFIG_9P_FSCACHE
208 * v9fs_alloc_inode - helper function to allocate an inode
209 * This callback is executed before setting up the inode so that we
210 * can associate a vcookie with each inode.
214 struct inode *v9fs_alloc_inode(struct super_block *sb)
216 struct v9fs_cookie *vcookie;
217 vcookie = (struct v9fs_cookie *)kmem_cache_alloc(vcookie_cache,
222 vcookie->fscache = NULL;
224 spin_lock_init(&vcookie->lock);
225 return &vcookie->inode;
229 * v9fs_destroy_inode - destroy an inode
233 static void v9fs_i_callback(struct rcu_head *head)
235 struct inode *inode = container_of(head, struct inode, i_rcu);
236 INIT_LIST_HEAD(&inode->i_dentry);
237 kmem_cache_free(vcookie_cache, v9fs_inode2cookie(inode));
240 void v9fs_destroy_inode(struct inode *inode)
242 call_rcu(&inode->i_rcu, v9fs_i_callback);
247 * v9fs_get_inode - helper function to setup an inode
249 * @mode: mode to setup inode with
253 struct inode *v9fs_get_inode(struct super_block *sb, int mode)
257 struct v9fs_session_info *v9ses = sb->s_fs_info;
259 P9_DPRINTK(P9_DEBUG_VFS, "super block: %p mode: %o\n", sb, mode);
261 inode = new_inode(sb);
263 P9_EPRINTK(KERN_WARNING, "Problem allocating inode\n");
264 return ERR_PTR(-ENOMEM);
267 inode_init_owner(inode, NULL, mode);
270 inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
271 inode->i_mapping->a_ops = &v9fs_addr_operations;
273 switch (mode & S_IFMT) {
278 if (v9fs_proto_dotl(v9ses)) {
279 inode->i_op = &v9fs_file_inode_operations_dotl;
280 inode->i_fop = &v9fs_file_operations_dotl;
281 } else if (v9fs_proto_dotu(v9ses)) {
282 inode->i_op = &v9fs_file_inode_operations;
283 inode->i_fop = &v9fs_file_operations;
285 P9_DPRINTK(P9_DEBUG_ERROR,
286 "special files without extended mode\n");
290 init_special_inode(inode, inode->i_mode, inode->i_rdev);
293 if (v9fs_proto_dotl(v9ses)) {
294 inode->i_op = &v9fs_file_inode_operations_dotl;
295 inode->i_fop = &v9fs_file_operations_dotl;
297 inode->i_op = &v9fs_file_inode_operations;
298 inode->i_fop = &v9fs_file_operations;
304 if (!v9fs_proto_dotu(v9ses) && !v9fs_proto_dotl(v9ses)) {
305 P9_DPRINTK(P9_DEBUG_ERROR, "extended modes used with "
306 "legacy protocol.\n");
311 if (v9fs_proto_dotl(v9ses))
312 inode->i_op = &v9fs_symlink_inode_operations_dotl;
314 inode->i_op = &v9fs_symlink_inode_operations;
319 if (v9fs_proto_dotl(v9ses))
320 inode->i_op = &v9fs_dir_inode_operations_dotl;
321 else if (v9fs_proto_dotu(v9ses))
322 inode->i_op = &v9fs_dir_inode_operations_dotu;
324 inode->i_op = &v9fs_dir_inode_operations;
326 if (v9fs_proto_dotl(v9ses))
327 inode->i_fop = &v9fs_dir_operations_dotl;
329 inode->i_fop = &v9fs_dir_operations;
333 P9_DPRINTK(P9_DEBUG_ERROR, "BAD mode 0x%x S_IFMT 0x%x\n",
334 mode, mode & S_IFMT);
347 static struct v9fs_fid*
348 v9fs_clone_walk(struct v9fs_session_info *v9ses, u32 fid, struct dentry *dentry)
352 struct v9fs_fid *ret;
353 struct v9fs_fcall *fcall;
355 nfid = v9fs_get_idpool(&v9ses->fidpool);
357 eprintk(KERN_WARNING, "no free fids available\n");
358 return ERR_PTR(-ENOSPC);
361 err = v9fs_t_walk(v9ses, fid, nfid, (char *) dentry->d_name.name,
365 if (fcall && fcall->id == RWALK)
368 PRINT_FCALL_ERROR("walk error", fcall);
369 v9fs_put_idpool(nfid, &v9ses->fidpool);
375 ret = v9fs_fid_create(v9ses, nfid);
381 err = v9fs_fid_insert(ret, dentry);
383 v9fs_fid_destroy(ret);
390 v9fs_t_clunk(v9ses, nfid);
400 * v9fs_clear_inode - release an inode
401 * @inode: inode to release
404 void v9fs_evict_inode(struct inode *inode)
406 truncate_inode_pages(inode->i_mapping, 0);
407 end_writeback(inode);
408 filemap_fdatawrite(inode->i_mapping);
410 #ifdef CONFIG_9P_FSCACHE
411 v9fs_cache_inode_put_cookie(inode);
416 v9fs_inode(struct v9fs_session_info *v9ses, struct p9_fid *fid,
417 struct super_block *sb)
420 struct inode *ret = NULL;
423 st = p9_client_stat(fid);
427 umode = p9mode2unixmode(v9ses, st->mode);
428 ret = v9fs_get_inode(sb, umode);
434 v9fs_stat2inode(st, ret, sb);
435 ret->i_ino = v9fs_qid2ino(&st->qid);
437 #ifdef CONFIG_9P_FSCACHE
438 v9fs_vcookie_set_qid(ret, &st->qid);
439 v9fs_cache_inode_get_cookie(ret);
451 * v9fs_remove - helper function to remove files and directories
452 * @dir: directory inode that is being deleted
453 * @file: dentry that is being deleted
454 * @rmdir: removing a directory
458 static int v9fs_remove(struct inode *dir, struct dentry *file, int rmdir)
461 struct inode *file_inode;
462 struct p9_fid *v9fid;
464 P9_DPRINTK(P9_DEBUG_VFS, "inode: %p dentry: %p rmdir: %d\n", dir, file,
467 file_inode = file->d_inode;
468 v9fid = v9fs_fid_clone(file);
470 return PTR_ERR(v9fid);
472 retval = p9_client_remove(v9fid);
474 drop_nlink(file_inode);
479 * v9fs_create - Create a file
480 * @v9ses: session information
481 * @dir: directory that dentry is being created in
482 * @dentry: dentry that is being created
483 * @extension: 9p2000.u extension string to support devices, etc.
484 * @perm: create permissions
488 static struct p9_fid *
489 v9fs_create(struct v9fs_session_info *v9ses, struct inode *dir,
490 struct dentry *dentry, char *extension, u32 perm, u8 mode)
494 struct p9_fid *dfid, *ofid, *fid;
497 P9_DPRINTK(P9_DEBUG_VFS, "name %s\n", dentry->d_name.name);
502 name = (char *) dentry->d_name.name;
503 dfid = v9fs_fid_lookup(dentry->d_parent);
506 P9_DPRINTK(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
510 /* clone a fid to use for creation */
511 ofid = p9_client_walk(dfid, 0, NULL, 1);
514 P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
518 err = p9_client_fcreate(ofid, name, perm, mode, extension);
520 P9_DPRINTK(P9_DEBUG_VFS, "p9_client_fcreate failed %d\n", err);
524 /* now walk from the parent so we can get unopened fid */
525 fid = p9_client_walk(dfid, 1, &name, 1);
528 P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
533 /* instantiate inode and assign the unopened fid to the dentry */
534 inode = v9fs_inode_from_fid(v9ses, fid, dir->i_sb);
536 err = PTR_ERR(inode);
537 P9_DPRINTK(P9_DEBUG_VFS, "inode creation failed %d\n", err);
540 d_instantiate(dentry, inode);
541 err = v9fs_fid_add(dentry, fid);
549 p9_client_clunk(ofid);
552 p9_client_clunk(fid);
558 * v9fs_vfs_create - VFS hook to create files
559 * @dir: directory inode that is being created
560 * @dentry: dentry that is being deleted
561 * @mode: create permissions
562 * @nd: path information
567 v9fs_vfs_create(struct inode *dir, struct dentry *dentry, int mode,
568 struct nameidata *nd)
573 struct v9fs_session_info *v9ses;
579 v9ses = v9fs_inode2v9ses(dir);
580 perm = unixmode2p9mode(v9ses, mode);
581 if (nd && nd->flags & LOOKUP_OPEN)
582 flags = nd->intent.open.flags - 1;
586 fid = v9fs_create(v9ses, dir, dentry, NULL, perm,
587 v9fs_uflags2omode(flags,
588 v9fs_proto_dotu(v9ses)));
595 /* if we are opening a file, assign the open fid to the file */
596 if (nd && nd->flags & LOOKUP_OPEN) {
597 filp = lookup_instantiate_filp(nd, dentry, generic_file_open);
603 filp->private_data = fid;
605 p9_client_clunk(fid);
611 p9_client_clunk(fid);
617 * v9fs_vfs_mkdir - VFS mkdir hook to create a directory
618 * @dir: inode that is being unlinked
619 * @dentry: dentry that is being unlinked
620 * @mode: mode for new directory
624 static int v9fs_vfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
628 struct v9fs_session_info *v9ses;
631 P9_DPRINTK(P9_DEBUG_VFS, "name %s\n", dentry->d_name.name);
633 v9ses = v9fs_inode2v9ses(dir);
634 perm = unixmode2p9mode(v9ses, mode | S_IFDIR);
635 fid = v9fs_create(v9ses, dir, dentry, NULL, perm, P9_OREAD);
642 p9_client_clunk(fid);
648 * v9fs_vfs_lookup - VFS lookup hook to "walk" to a new inode
649 * @dir: inode that is being walked from
650 * @dentry: dentry that is being walked to?
651 * @nameidata: path data
655 struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
656 struct nameidata *nameidata)
658 struct super_block *sb;
659 struct v9fs_session_info *v9ses;
660 struct p9_fid *dfid, *fid;
665 P9_DPRINTK(P9_DEBUG_VFS, "dir: %p dentry: (%s) %p nameidata: %p\n",
666 dir, dentry->d_name.name, dentry, nameidata);
668 if (dentry->d_name.len > NAME_MAX)
669 return ERR_PTR(-ENAMETOOLONG);
672 v9ses = v9fs_inode2v9ses(dir);
673 /* We can walk d_parent because we hold the dir->i_mutex */
674 dfid = v9fs_fid_lookup(dentry->d_parent);
676 return ERR_CAST(dfid);
678 name = (char *) dentry->d_name.name;
679 fid = p9_client_walk(dfid, 1, &name, 1);
681 result = PTR_ERR(fid);
682 if (result == -ENOENT) {
687 return ERR_PTR(result);
690 inode = v9fs_inode_from_fid(v9ses, fid, dir->i_sb);
692 result = PTR_ERR(inode);
697 result = v9fs_fid_add(dentry, fid);
703 d_set_d_op(dentry, &v9fs_cached_dentry_operations);
705 d_set_d_op(dentry, &v9fs_dentry_operations);
707 d_add(dentry, inode);
713 p9_client_clunk(fid);
715 return ERR_PTR(result);
719 * v9fs_vfs_unlink - VFS unlink hook to delete an inode
720 * @i: inode that is being unlinked
721 * @d: dentry that is being unlinked
725 int v9fs_vfs_unlink(struct inode *i, struct dentry *d)
727 return v9fs_remove(i, d, 0);
731 * v9fs_vfs_rmdir - VFS unlink hook to delete a directory
732 * @i: inode that is being unlinked
733 * @d: dentry that is being unlinked
737 int v9fs_vfs_rmdir(struct inode *i, struct dentry *d)
739 return v9fs_remove(i, d, 1);
743 * v9fs_vfs_rename - VFS hook to rename an inode
744 * @old_dir: old dir inode
745 * @old_dentry: old dentry
746 * @new_dir: new dir inode
747 * @new_dentry: new dentry
752 v9fs_vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
753 struct inode *new_dir, struct dentry *new_dentry)
755 struct inode *old_inode;
756 struct v9fs_session_info *v9ses;
757 struct p9_fid *oldfid;
758 struct p9_fid *olddirfid;
759 struct p9_fid *newdirfid;
760 struct p9_wstat wstat;
763 P9_DPRINTK(P9_DEBUG_VFS, "\n");
765 old_inode = old_dentry->d_inode;
766 v9ses = v9fs_inode2v9ses(old_inode);
767 oldfid = v9fs_fid_lookup(old_dentry);
769 return PTR_ERR(oldfid);
771 olddirfid = v9fs_fid_clone(old_dentry->d_parent);
772 if (IS_ERR(olddirfid)) {
773 retval = PTR_ERR(olddirfid);
777 newdirfid = v9fs_fid_clone(new_dentry->d_parent);
778 if (IS_ERR(newdirfid)) {
779 retval = PTR_ERR(newdirfid);
783 down_write(&v9ses->rename_sem);
784 if (v9fs_proto_dotl(v9ses)) {
785 retval = p9_client_rename(oldfid, newdirfid,
786 (char *) new_dentry->d_name.name);
787 if (retval != -ENOSYS)
790 if (old_dentry->d_parent != new_dentry->d_parent) {
792 * 9P .u can only handle file rename in the same directory
795 P9_DPRINTK(P9_DEBUG_ERROR,
796 "old dir and new dir are different\n");
800 v9fs_blank_wstat(&wstat);
801 wstat.muid = v9ses->uname;
802 wstat.name = (char *) new_dentry->d_name.name;
803 retval = p9_client_wstat(oldfid, &wstat);
807 /* successful rename */
808 d_move(old_dentry, new_dentry);
809 up_write(&v9ses->rename_sem);
810 p9_client_clunk(newdirfid);
813 p9_client_clunk(olddirfid);
820 * v9fs_vfs_getattr - retrieve file metadata
821 * @mnt: mount information
822 * @dentry: file to get attributes on
823 * @stat: metadata structure to populate
828 v9fs_vfs_getattr(struct vfsmount *mnt, struct dentry *dentry,
832 struct v9fs_session_info *v9ses;
836 P9_DPRINTK(P9_DEBUG_VFS, "dentry: %p\n", dentry);
838 v9ses = v9fs_inode2v9ses(dentry->d_inode);
839 if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
840 return simple_getattr(mnt, dentry, stat);
842 fid = v9fs_fid_lookup(dentry);
846 st = p9_client_stat(fid);
850 v9fs_stat2inode(st, dentry->d_inode, dentry->d_inode->i_sb);
851 generic_fillattr(dentry->d_inode, stat);
859 * v9fs_vfs_setattr - set file metadata
860 * @dentry: file whose metadata to set
861 * @iattr: metadata assignment structure
865 static int v9fs_vfs_setattr(struct dentry *dentry, struct iattr *iattr)
868 struct v9fs_session_info *v9ses;
870 struct p9_wstat wstat;
872 P9_DPRINTK(P9_DEBUG_VFS, "\n");
874 v9ses = v9fs_inode2v9ses(dentry->d_inode);
875 fid = v9fs_fid_lookup(dentry);
879 v9fs_blank_wstat(&wstat);
880 if (iattr->ia_valid & ATTR_MODE)
881 wstat.mode = unixmode2p9mode(v9ses, iattr->ia_mode);
883 if (iattr->ia_valid & ATTR_MTIME)
884 wstat.mtime = iattr->ia_mtime.tv_sec;
886 if (iattr->ia_valid & ATTR_ATIME)
887 wstat.atime = iattr->ia_atime.tv_sec;
889 if (iattr->ia_valid & ATTR_SIZE)
890 wstat.length = iattr->ia_size;
892 if (v9fs_proto_dotu(v9ses)) {
893 if (iattr->ia_valid & ATTR_UID)
894 wstat.n_uid = iattr->ia_uid;
896 if (iattr->ia_valid & ATTR_GID)
897 wstat.n_gid = iattr->ia_gid;
900 retval = p9_client_wstat(fid, &wstat);
904 if ((iattr->ia_valid & ATTR_SIZE) &&
905 iattr->ia_size != i_size_read(dentry->d_inode)) {
906 retval = vmtruncate(dentry->d_inode, iattr->ia_size);
911 setattr_copy(dentry->d_inode, iattr);
912 mark_inode_dirty(dentry->d_inode);
917 * v9fs_stat2inode - populate an inode structure with mistat info
918 * @stat: Plan 9 metadata (mistat) structure
919 * @inode: inode to populate
920 * @sb: superblock of filesystem
925 v9fs_stat2inode(struct p9_wstat *stat, struct inode *inode,
926 struct super_block *sb)
930 unsigned int i_nlink;
931 struct v9fs_session_info *v9ses = sb->s_fs_info;
935 inode->i_atime.tv_sec = stat->atime;
936 inode->i_mtime.tv_sec = stat->mtime;
937 inode->i_ctime.tv_sec = stat->mtime;
939 inode->i_uid = v9ses->dfltuid;
940 inode->i_gid = v9ses->dfltgid;
942 if (v9fs_proto_dotu(v9ses)) {
943 inode->i_uid = stat->n_uid;
944 inode->i_gid = stat->n_gid;
946 if ((S_ISREG(inode->i_mode)) || (S_ISDIR(inode->i_mode))) {
947 if (v9fs_proto_dotu(v9ses) && (stat->extension[0] != '\0')) {
949 * Hadlink support got added later to
950 * to the .u extension. So there can be
951 * server out there that doesn't support
952 * this even with .u extension. So check
953 * for non NULL stat->extension
955 strncpy(ext, stat->extension, sizeof(ext));
956 /* HARDLINKCOUNT %u */
957 sscanf(ext, "%13s %u", tag_name, &i_nlink);
958 if (!strncmp(tag_name, "HARDLINKCOUNT", 13))
959 inode->i_nlink = i_nlink;
962 inode->i_mode = p9mode2unixmode(v9ses, stat->mode);
963 if ((S_ISBLK(inode->i_mode)) || (S_ISCHR(inode->i_mode))) {
968 strncpy(ext, stat->extension, sizeof(ext));
969 sscanf(ext, "%c %u %u", &type, &major, &minor);
972 inode->i_mode &= ~S_IFBLK;
973 inode->i_mode |= S_IFCHR;
978 P9_DPRINTK(P9_DEBUG_ERROR,
979 "Unknown special type %c %s\n", type,
982 inode->i_rdev = MKDEV(major, minor);
983 init_special_inode(inode, inode->i_mode, inode->i_rdev);
987 i_size_write(inode, stat->length);
989 /* not real number of blocks, but 512 byte ones ... */
990 inode->i_blocks = (i_size_read(inode) + 512 - 1) >> 9;
994 * v9fs_qid2ino - convert qid into inode number
997 * BUG: potential for inode number collisions?
1000 ino_t v9fs_qid2ino(struct p9_qid *qid)
1002 u64 path = qid->path + 2;
1005 if (sizeof(ino_t) == sizeof(path))
1006 memcpy(&i, &path, sizeof(ino_t));
1008 i = (ino_t) (path ^ (path >> 32));
1014 * v9fs_readlink - read a symlink's location (internal version)
1015 * @dentry: dentry for symlink
1016 * @buffer: buffer to load symlink location into
1017 * @buflen: length of buffer
1021 static int v9fs_readlink(struct dentry *dentry, char *buffer, int buflen)
1025 struct v9fs_session_info *v9ses;
1027 struct p9_wstat *st;
1029 P9_DPRINTK(P9_DEBUG_VFS, " %s\n", dentry->d_name.name);
1031 v9ses = v9fs_inode2v9ses(dentry->d_inode);
1032 fid = v9fs_fid_lookup(dentry);
1034 return PTR_ERR(fid);
1036 if (!v9fs_proto_dotu(v9ses))
1039 st = p9_client_stat(fid);
1043 if (!(st->mode & P9_DMSYMLINK)) {
1048 /* copy extension buffer into buffer */
1049 strncpy(buffer, st->extension, buflen);
1051 P9_DPRINTK(P9_DEBUG_VFS,
1052 "%s -> %s (%s)\n", dentry->d_name.name, st->extension, buffer);
1054 retval = strnlen(buffer, buflen);
1062 * v9fs_vfs_follow_link - follow a symlink path
1063 * @dentry: dentry for symlink
1068 static void *v9fs_vfs_follow_link(struct dentry *dentry, struct nameidata *nd)
1071 char *link = __getname();
1073 P9_DPRINTK(P9_DEBUG_VFS, "%s n", dentry->d_name.name);
1076 link = ERR_PTR(-ENOMEM);
1078 len = v9fs_readlink(dentry, link, PATH_MAX);
1082 link = ERR_PTR(len);
1084 link[min(len, PATH_MAX-1)] = 0;
1086 nd_set_link(nd, link);
1092 * v9fs_vfs_put_link - release a symlink path
1093 * @dentry: dentry for symlink
1100 v9fs_vfs_put_link(struct dentry *dentry, struct nameidata *nd, void *p)
1102 char *s = nd_get_link(nd);
1104 P9_DPRINTK(P9_DEBUG_VFS, " %s %s\n", dentry->d_name.name,
1105 IS_ERR(s) ? "<error>" : s);
1111 * v9fs_vfs_mkspecial - create a special file
1112 * @dir: inode to create special file in
1113 * @dentry: dentry to create
1114 * @mode: mode to create special file
1115 * @extension: 9p2000.u format extension string representing special file
1119 static int v9fs_vfs_mkspecial(struct inode *dir, struct dentry *dentry,
1120 int mode, const char *extension)
1123 struct v9fs_session_info *v9ses;
1126 v9ses = v9fs_inode2v9ses(dir);
1127 if (!v9fs_proto_dotu(v9ses)) {
1128 P9_DPRINTK(P9_DEBUG_ERROR, "not extended\n");
1132 perm = unixmode2p9mode(v9ses, mode);
1133 fid = v9fs_create(v9ses, dir, dentry, (char *) extension, perm,
1136 return PTR_ERR(fid);
1138 p9_client_clunk(fid);
1143 * v9fs_vfs_symlink - helper function to create symlinks
1144 * @dir: directory inode containing symlink
1145 * @dentry: dentry for symlink
1146 * @symname: symlink data
1148 * See Also: 9P2000.u RFC for more information
1153 v9fs_vfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname)
1155 P9_DPRINTK(P9_DEBUG_VFS, " %lu,%s,%s\n", dir->i_ino,
1156 dentry->d_name.name, symname);
1158 return v9fs_vfs_mkspecial(dir, dentry, S_IFLNK, symname);
1162 * v9fs_vfs_link - create a hardlink
1163 * @old_dentry: dentry for file to link to
1164 * @dir: inode destination for new link
1165 * @dentry: dentry for link
1170 v9fs_vfs_link(struct dentry *old_dentry, struct inode *dir,
1171 struct dentry *dentry)
1174 struct p9_fid *oldfid;
1177 P9_DPRINTK(P9_DEBUG_VFS,
1178 " %lu,%s,%s\n", dir->i_ino, dentry->d_name.name,
1179 old_dentry->d_name.name);
1181 oldfid = v9fs_fid_clone(old_dentry);
1183 return PTR_ERR(oldfid);
1186 if (unlikely(!name)) {
1191 sprintf(name, "%d\n", oldfid->fid);
1192 retval = v9fs_vfs_mkspecial(dir, dentry, P9_DMLINK, name);
1196 p9_client_clunk(oldfid);
1201 * v9fs_vfs_mknod - create a special file
1202 * @dir: inode destination for new link
1203 * @dentry: dentry for file
1204 * @mode: mode for creation
1205 * @rdev: device associated with special file
1210 v9fs_vfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t rdev)
1215 P9_DPRINTK(P9_DEBUG_VFS,
1216 " %lu,%s mode: %x MAJOR: %u MINOR: %u\n", dir->i_ino,
1217 dentry->d_name.name, mode, MAJOR(rdev), MINOR(rdev));
1219 if (!new_valid_dev(rdev))
1225 /* build extension */
1227 sprintf(name, "b %u %u", MAJOR(rdev), MINOR(rdev));
1228 else if (S_ISCHR(mode))
1229 sprintf(name, "c %u %u", MAJOR(rdev), MINOR(rdev));
1230 else if (S_ISFIFO(mode))
1232 else if (S_ISSOCK(mode))
1239 retval = v9fs_vfs_mkspecial(dir, dentry, mode, name);
1245 static const struct inode_operations v9fs_dir_inode_operations_dotu = {
1246 .create = v9fs_vfs_create,
1247 .lookup = v9fs_vfs_lookup,
1248 .symlink = v9fs_vfs_symlink,
1249 .link = v9fs_vfs_link,
1250 .unlink = v9fs_vfs_unlink,
1251 .mkdir = v9fs_vfs_mkdir,
1252 .rmdir = v9fs_vfs_rmdir,
1253 .mknod = v9fs_vfs_mknod,
1254 .rename = v9fs_vfs_rename,
1255 .getattr = v9fs_vfs_getattr,
1256 .setattr = v9fs_vfs_setattr,
1259 static const struct inode_operations v9fs_dir_inode_operations = {
1260 .create = v9fs_vfs_create,
1261 .lookup = v9fs_vfs_lookup,
1262 .unlink = v9fs_vfs_unlink,
1263 .mkdir = v9fs_vfs_mkdir,
1264 .rmdir = v9fs_vfs_rmdir,
1265 .mknod = v9fs_vfs_mknod,
1266 .rename = v9fs_vfs_rename,
1267 .getattr = v9fs_vfs_getattr,
1268 .setattr = v9fs_vfs_setattr,
1271 static const struct inode_operations v9fs_file_inode_operations = {
1272 .getattr = v9fs_vfs_getattr,
1273 .setattr = v9fs_vfs_setattr,
1276 static const struct inode_operations v9fs_symlink_inode_operations = {
1277 .readlink = generic_readlink,
1278 .follow_link = v9fs_vfs_follow_link,
1279 .put_link = v9fs_vfs_put_link,
1280 .getattr = v9fs_vfs_getattr,
1281 .setattr = v9fs_vfs_setattr,