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);
246 int v9fs_init_inode(struct v9fs_session_info *v9ses,
247 struct inode *inode, int mode)
251 inode_init_owner(inode, NULL, mode);
254 inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
255 inode->i_mapping->a_ops = &v9fs_addr_operations;
257 switch (mode & S_IFMT) {
262 if (v9fs_proto_dotl(v9ses)) {
263 inode->i_op = &v9fs_file_inode_operations_dotl;
264 inode->i_fop = &v9fs_file_operations_dotl;
265 } else if (v9fs_proto_dotu(v9ses)) {
266 inode->i_op = &v9fs_file_inode_operations;
267 inode->i_fop = &v9fs_file_operations;
269 P9_DPRINTK(P9_DEBUG_ERROR,
270 "special files without extended mode\n");
274 init_special_inode(inode, inode->i_mode, inode->i_rdev);
277 if (v9fs_proto_dotl(v9ses)) {
278 inode->i_op = &v9fs_file_inode_operations_dotl;
281 &v9fs_cached_file_operations_dotl;
283 inode->i_fop = &v9fs_file_operations_dotl;
285 inode->i_op = &v9fs_file_inode_operations;
287 inode->i_fop = &v9fs_cached_file_operations;
289 inode->i_fop = &v9fs_file_operations;
294 if (!v9fs_proto_dotu(v9ses) && !v9fs_proto_dotl(v9ses)) {
295 P9_DPRINTK(P9_DEBUG_ERROR, "extended modes used with "
296 "legacy protocol.\n");
301 if (v9fs_proto_dotl(v9ses))
302 inode->i_op = &v9fs_symlink_inode_operations_dotl;
304 inode->i_op = &v9fs_symlink_inode_operations;
309 if (v9fs_proto_dotl(v9ses))
310 inode->i_op = &v9fs_dir_inode_operations_dotl;
311 else if (v9fs_proto_dotu(v9ses))
312 inode->i_op = &v9fs_dir_inode_operations_dotu;
314 inode->i_op = &v9fs_dir_inode_operations;
316 if (v9fs_proto_dotl(v9ses))
317 inode->i_fop = &v9fs_dir_operations_dotl;
319 inode->i_fop = &v9fs_dir_operations;
323 P9_DPRINTK(P9_DEBUG_ERROR, "BAD mode 0x%x S_IFMT 0x%x\n",
324 mode, mode & S_IFMT);
334 * v9fs_get_inode - helper function to setup an inode
336 * @mode: mode to setup inode with
340 struct inode *v9fs_get_inode(struct super_block *sb, int mode)
344 struct v9fs_session_info *v9ses = sb->s_fs_info;
346 P9_DPRINTK(P9_DEBUG_VFS, "super block: %p mode: %o\n", sb, mode);
348 inode = new_inode(sb);
350 P9_EPRINTK(KERN_WARNING, "Problem allocating inode\n");
351 return ERR_PTR(-ENOMEM);
353 err = v9fs_init_inode(v9ses, inode, mode);
362 static struct v9fs_fid*
363 v9fs_clone_walk(struct v9fs_session_info *v9ses, u32 fid, struct dentry *dentry)
367 struct v9fs_fid *ret;
368 struct v9fs_fcall *fcall;
370 nfid = v9fs_get_idpool(&v9ses->fidpool);
372 eprintk(KERN_WARNING, "no free fids available\n");
373 return ERR_PTR(-ENOSPC);
376 err = v9fs_t_walk(v9ses, fid, nfid, (char *) dentry->d_name.name,
380 if (fcall && fcall->id == RWALK)
383 PRINT_FCALL_ERROR("walk error", fcall);
384 v9fs_put_idpool(nfid, &v9ses->fidpool);
390 ret = v9fs_fid_create(v9ses, nfid);
396 err = v9fs_fid_insert(ret, dentry);
398 v9fs_fid_destroy(ret);
405 v9fs_t_clunk(v9ses, nfid);
415 * v9fs_clear_inode - release an inode
416 * @inode: inode to release
419 void v9fs_evict_inode(struct inode *inode)
421 truncate_inode_pages(inode->i_mapping, 0);
422 end_writeback(inode);
423 filemap_fdatawrite(inode->i_mapping);
425 #ifdef CONFIG_9P_FSCACHE
426 v9fs_cache_inode_put_cookie(inode);
428 /* clunk the fid stashed in inode->i_private */
429 if (inode->i_private) {
430 p9_client_clunk((struct p9_fid *)inode->i_private);
431 inode->i_private = NULL;
435 static struct inode *v9fs_qid_iget(struct super_block *sb,
442 struct v9fs_session_info *v9ses = sb->s_fs_info;
444 i_ino = v9fs_qid2ino(qid);
445 inode = iget_locked(sb, i_ino);
447 return ERR_PTR(-ENOMEM);
448 if (!(inode->i_state & I_NEW))
451 * initialize the inode with the stat info
452 * FIXME!! we may need support for stale inodes
455 umode = p9mode2unixmode(v9ses, st->mode);
456 retval = v9fs_init_inode(v9ses, inode, umode);
460 v9fs_stat2inode(st, inode, sb);
461 #ifdef CONFIG_9P_FSCACHE
462 v9fs_vcookie_set_qid(ret, &st->qid);
463 v9fs_cache_inode_get_cookie(inode);
465 unlock_new_inode(inode);
468 unlock_new_inode(inode);
470 return ERR_PTR(retval);
475 v9fs_inode(struct v9fs_session_info *v9ses, struct p9_fid *fid,
476 struct super_block *sb)
479 struct inode *inode = NULL;
481 st = p9_client_stat(fid);
485 inode = v9fs_qid_iget(sb, &st->qid, st);
492 * v9fs_remove - helper function to remove files and directories
493 * @dir: directory inode that is being deleted
494 * @file: dentry that is being deleted
495 * @rmdir: removing a directory
499 static int v9fs_remove(struct inode *dir, struct dentry *file, int rmdir)
502 struct inode *file_inode;
503 struct p9_fid *v9fid;
505 P9_DPRINTK(P9_DEBUG_VFS, "inode: %p dentry: %p rmdir: %d\n", dir, file,
508 file_inode = file->d_inode;
509 v9fid = v9fs_fid_clone(file);
511 return PTR_ERR(v9fid);
513 retval = p9_client_remove(v9fid);
515 drop_nlink(file_inode);
520 * v9fs_create - Create a file
521 * @v9ses: session information
522 * @dir: directory that dentry is being created in
523 * @dentry: dentry that is being created
524 * @extension: 9p2000.u extension string to support devices, etc.
525 * @perm: create permissions
529 static struct p9_fid *
530 v9fs_create(struct v9fs_session_info *v9ses, struct inode *dir,
531 struct dentry *dentry, char *extension, u32 perm, u8 mode)
535 struct p9_fid *dfid, *ofid, *fid;
538 P9_DPRINTK(P9_DEBUG_VFS, "name %s\n", dentry->d_name.name);
543 name = (char *) dentry->d_name.name;
544 dfid = v9fs_fid_lookup(dentry->d_parent);
547 P9_DPRINTK(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
551 /* clone a fid to use for creation */
552 ofid = p9_client_walk(dfid, 0, NULL, 1);
555 P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
559 err = p9_client_fcreate(ofid, name, perm, mode, extension);
561 P9_DPRINTK(P9_DEBUG_VFS, "p9_client_fcreate failed %d\n", err);
565 /* now walk from the parent so we can get unopened fid */
566 fid = p9_client_walk(dfid, 1, &name, 1);
569 P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
574 /* instantiate inode and assign the unopened fid to the dentry */
575 inode = v9fs_inode_from_fid(v9ses, fid, dir->i_sb);
577 err = PTR_ERR(inode);
578 P9_DPRINTK(P9_DEBUG_VFS, "inode creation failed %d\n", err);
581 d_instantiate(dentry, inode);
582 err = v9fs_fid_add(dentry, fid);
590 p9_client_clunk(ofid);
593 p9_client_clunk(fid);
599 * v9fs_vfs_create - VFS hook to create files
600 * @dir: directory inode that is being created
601 * @dentry: dentry that is being deleted
602 * @mode: create permissions
603 * @nd: path information
608 v9fs_vfs_create(struct inode *dir, struct dentry *dentry, int mode,
609 struct nameidata *nd)
614 struct v9fs_session_info *v9ses;
615 struct p9_fid *fid, *inode_fid;
620 v9ses = v9fs_inode2v9ses(dir);
621 perm = unixmode2p9mode(v9ses, mode);
622 if (nd && nd->flags & LOOKUP_OPEN)
623 flags = nd->intent.open.flags - 1;
627 fid = v9fs_create(v9ses, dir, dentry, NULL, perm,
628 v9fs_uflags2omode(flags,
629 v9fs_proto_dotu(v9ses)));
636 /* if we are opening a file, assign the open fid to the file */
637 if (nd && nd->flags & LOOKUP_OPEN) {
638 if (v9ses->cache && !dentry->d_inode->i_private) {
640 * clone a fid and add it to inode->i_private
641 * we do it during open time instead of
642 * page dirty time via write_begin/page_mkwrite
643 * because we want write after unlink usecase
646 inode_fid = v9fs_writeback_fid(dentry);
647 if (IS_ERR(inode_fid)) {
648 err = PTR_ERR(inode_fid);
651 dentry->d_inode->i_private = (void *) inode_fid;
653 filp = lookup_instantiate_filp(nd, dentry, generic_file_open);
659 filp->private_data = fid;
660 #ifdef CONFIG_9P_FSCACHE
662 v9fs_cache_inode_set_cookie(dentry->d_inode, filp);
665 p9_client_clunk(fid);
671 p9_client_clunk(fid);
677 * v9fs_vfs_mkdir - VFS mkdir hook to create a directory
678 * @dir: inode that is being unlinked
679 * @dentry: dentry that is being unlinked
680 * @mode: mode for new directory
684 static int v9fs_vfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
688 struct v9fs_session_info *v9ses;
691 P9_DPRINTK(P9_DEBUG_VFS, "name %s\n", dentry->d_name.name);
693 v9ses = v9fs_inode2v9ses(dir);
694 perm = unixmode2p9mode(v9ses, mode | S_IFDIR);
695 fid = v9fs_create(v9ses, dir, dentry, NULL, perm, P9_OREAD);
702 p9_client_clunk(fid);
708 * v9fs_vfs_lookup - VFS lookup hook to "walk" to a new inode
709 * @dir: inode that is being walked from
710 * @dentry: dentry that is being walked to?
711 * @nameidata: path data
715 struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
716 struct nameidata *nameidata)
718 struct super_block *sb;
719 struct v9fs_session_info *v9ses;
720 struct p9_fid *dfid, *fid;
725 P9_DPRINTK(P9_DEBUG_VFS, "dir: %p dentry: (%s) %p nameidata: %p\n",
726 dir, dentry->d_name.name, dentry, nameidata);
728 if (dentry->d_name.len > NAME_MAX)
729 return ERR_PTR(-ENAMETOOLONG);
732 v9ses = v9fs_inode2v9ses(dir);
733 /* We can walk d_parent because we hold the dir->i_mutex */
734 dfid = v9fs_fid_lookup(dentry->d_parent);
736 return ERR_CAST(dfid);
738 name = (char *) dentry->d_name.name;
739 fid = p9_client_walk(dfid, 1, &name, 1);
741 result = PTR_ERR(fid);
742 if (result == -ENOENT) {
747 return ERR_PTR(result);
750 inode = v9fs_inode_from_fid(v9ses, fid, dir->i_sb);
752 result = PTR_ERR(inode);
757 result = v9fs_fid_add(dentry, fid);
762 d_add(dentry, inode);
768 p9_client_clunk(fid);
770 return ERR_PTR(result);
774 * v9fs_vfs_unlink - VFS unlink hook to delete an inode
775 * @i: inode that is being unlinked
776 * @d: dentry that is being unlinked
780 int v9fs_vfs_unlink(struct inode *i, struct dentry *d)
782 return v9fs_remove(i, d, 0);
786 * v9fs_vfs_rmdir - VFS unlink hook to delete a directory
787 * @i: inode that is being unlinked
788 * @d: dentry that is being unlinked
792 int v9fs_vfs_rmdir(struct inode *i, struct dentry *d)
794 return v9fs_remove(i, d, 1);
798 * v9fs_vfs_rename - VFS hook to rename an inode
799 * @old_dir: old dir inode
800 * @old_dentry: old dentry
801 * @new_dir: new dir inode
802 * @new_dentry: new dentry
807 v9fs_vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
808 struct inode *new_dir, struct dentry *new_dentry)
810 struct inode *old_inode;
811 struct v9fs_session_info *v9ses;
812 struct p9_fid *oldfid;
813 struct p9_fid *olddirfid;
814 struct p9_fid *newdirfid;
815 struct p9_wstat wstat;
818 P9_DPRINTK(P9_DEBUG_VFS, "\n");
820 old_inode = old_dentry->d_inode;
821 v9ses = v9fs_inode2v9ses(old_inode);
822 oldfid = v9fs_fid_lookup(old_dentry);
824 return PTR_ERR(oldfid);
826 olddirfid = v9fs_fid_clone(old_dentry->d_parent);
827 if (IS_ERR(olddirfid)) {
828 retval = PTR_ERR(olddirfid);
832 newdirfid = v9fs_fid_clone(new_dentry->d_parent);
833 if (IS_ERR(newdirfid)) {
834 retval = PTR_ERR(newdirfid);
838 down_write(&v9ses->rename_sem);
839 if (v9fs_proto_dotl(v9ses)) {
840 retval = p9_client_rename(oldfid, newdirfid,
841 (char *) new_dentry->d_name.name);
842 if (retval != -ENOSYS)
845 if (old_dentry->d_parent != new_dentry->d_parent) {
847 * 9P .u can only handle file rename in the same directory
850 P9_DPRINTK(P9_DEBUG_ERROR,
851 "old dir and new dir are different\n");
855 v9fs_blank_wstat(&wstat);
856 wstat.muid = v9ses->uname;
857 wstat.name = (char *) new_dentry->d_name.name;
858 retval = p9_client_wstat(oldfid, &wstat);
862 /* successful rename */
863 d_move(old_dentry, new_dentry);
864 up_write(&v9ses->rename_sem);
865 p9_client_clunk(newdirfid);
868 p9_client_clunk(olddirfid);
875 * v9fs_vfs_getattr - retrieve file metadata
876 * @mnt: mount information
877 * @dentry: file to get attributes on
878 * @stat: metadata structure to populate
883 v9fs_vfs_getattr(struct vfsmount *mnt, struct dentry *dentry,
887 struct v9fs_session_info *v9ses;
891 P9_DPRINTK(P9_DEBUG_VFS, "dentry: %p\n", dentry);
893 v9ses = v9fs_inode2v9ses(dentry->d_inode);
894 if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
895 return simple_getattr(mnt, dentry, stat);
897 fid = v9fs_fid_lookup(dentry);
901 st = p9_client_stat(fid);
905 v9fs_stat2inode(st, dentry->d_inode, dentry->d_inode->i_sb);
906 generic_fillattr(dentry->d_inode, stat);
914 * v9fs_vfs_setattr - set file metadata
915 * @dentry: file whose metadata to set
916 * @iattr: metadata assignment structure
920 static int v9fs_vfs_setattr(struct dentry *dentry, struct iattr *iattr)
923 struct v9fs_session_info *v9ses;
925 struct p9_wstat wstat;
927 P9_DPRINTK(P9_DEBUG_VFS, "\n");
929 v9ses = v9fs_inode2v9ses(dentry->d_inode);
930 fid = v9fs_fid_lookup(dentry);
934 v9fs_blank_wstat(&wstat);
935 if (iattr->ia_valid & ATTR_MODE)
936 wstat.mode = unixmode2p9mode(v9ses, iattr->ia_mode);
938 if (iattr->ia_valid & ATTR_MTIME)
939 wstat.mtime = iattr->ia_mtime.tv_sec;
941 if (iattr->ia_valid & ATTR_ATIME)
942 wstat.atime = iattr->ia_atime.tv_sec;
944 if (iattr->ia_valid & ATTR_SIZE)
945 wstat.length = iattr->ia_size;
947 if (v9fs_proto_dotu(v9ses)) {
948 if (iattr->ia_valid & ATTR_UID)
949 wstat.n_uid = iattr->ia_uid;
951 if (iattr->ia_valid & ATTR_GID)
952 wstat.n_gid = iattr->ia_gid;
955 retval = p9_client_wstat(fid, &wstat);
959 if ((iattr->ia_valid & ATTR_SIZE) &&
960 iattr->ia_size != i_size_read(dentry->d_inode)) {
961 retval = vmtruncate(dentry->d_inode, iattr->ia_size);
966 setattr_copy(dentry->d_inode, iattr);
967 mark_inode_dirty(dentry->d_inode);
972 * v9fs_stat2inode - populate an inode structure with mistat info
973 * @stat: Plan 9 metadata (mistat) structure
974 * @inode: inode to populate
975 * @sb: superblock of filesystem
980 v9fs_stat2inode(struct p9_wstat *stat, struct inode *inode,
981 struct super_block *sb)
985 unsigned int i_nlink;
986 struct v9fs_session_info *v9ses = sb->s_fs_info;
990 inode->i_atime.tv_sec = stat->atime;
991 inode->i_mtime.tv_sec = stat->mtime;
992 inode->i_ctime.tv_sec = stat->mtime;
994 inode->i_uid = v9ses->dfltuid;
995 inode->i_gid = v9ses->dfltgid;
997 if (v9fs_proto_dotu(v9ses)) {
998 inode->i_uid = stat->n_uid;
999 inode->i_gid = stat->n_gid;
1001 if ((S_ISREG(inode->i_mode)) || (S_ISDIR(inode->i_mode))) {
1002 if (v9fs_proto_dotu(v9ses) && (stat->extension[0] != '\0')) {
1004 * Hadlink support got added later to
1005 * to the .u extension. So there can be
1006 * server out there that doesn't support
1007 * this even with .u extension. So check
1008 * for non NULL stat->extension
1010 strncpy(ext, stat->extension, sizeof(ext));
1011 /* HARDLINKCOUNT %u */
1012 sscanf(ext, "%13s %u", tag_name, &i_nlink);
1013 if (!strncmp(tag_name, "HARDLINKCOUNT", 13))
1014 inode->i_nlink = i_nlink;
1017 inode->i_mode = p9mode2unixmode(v9ses, stat->mode);
1018 if ((S_ISBLK(inode->i_mode)) || (S_ISCHR(inode->i_mode))) {
1023 strncpy(ext, stat->extension, sizeof(ext));
1024 sscanf(ext, "%c %u %u", &type, &major, &minor);
1027 inode->i_mode &= ~S_IFBLK;
1028 inode->i_mode |= S_IFCHR;
1033 P9_DPRINTK(P9_DEBUG_ERROR,
1034 "Unknown special type %c %s\n", type,
1037 inode->i_rdev = MKDEV(major, minor);
1038 init_special_inode(inode, inode->i_mode, inode->i_rdev);
1042 i_size_write(inode, stat->length);
1044 /* not real number of blocks, but 512 byte ones ... */
1045 inode->i_blocks = (i_size_read(inode) + 512 - 1) >> 9;
1049 * v9fs_qid2ino - convert qid into inode number
1052 * BUG: potential for inode number collisions?
1055 ino_t v9fs_qid2ino(struct p9_qid *qid)
1057 u64 path = qid->path + 2;
1060 if (sizeof(ino_t) == sizeof(path))
1061 memcpy(&i, &path, sizeof(ino_t));
1063 i = (ino_t) (path ^ (path >> 32));
1069 * v9fs_readlink - read a symlink's location (internal version)
1070 * @dentry: dentry for symlink
1071 * @buffer: buffer to load symlink location into
1072 * @buflen: length of buffer
1076 static int v9fs_readlink(struct dentry *dentry, char *buffer, int buflen)
1080 struct v9fs_session_info *v9ses;
1082 struct p9_wstat *st;
1084 P9_DPRINTK(P9_DEBUG_VFS, " %s\n", dentry->d_name.name);
1086 v9ses = v9fs_inode2v9ses(dentry->d_inode);
1087 fid = v9fs_fid_lookup(dentry);
1089 return PTR_ERR(fid);
1091 if (!v9fs_proto_dotu(v9ses))
1094 st = p9_client_stat(fid);
1098 if (!(st->mode & P9_DMSYMLINK)) {
1103 /* copy extension buffer into buffer */
1104 strncpy(buffer, st->extension, buflen);
1106 P9_DPRINTK(P9_DEBUG_VFS,
1107 "%s -> %s (%s)\n", dentry->d_name.name, st->extension, buffer);
1109 retval = strnlen(buffer, buflen);
1117 * v9fs_vfs_follow_link - follow a symlink path
1118 * @dentry: dentry for symlink
1123 static void *v9fs_vfs_follow_link(struct dentry *dentry, struct nameidata *nd)
1126 char *link = __getname();
1128 P9_DPRINTK(P9_DEBUG_VFS, "%s n", dentry->d_name.name);
1131 link = ERR_PTR(-ENOMEM);
1133 len = v9fs_readlink(dentry, link, PATH_MAX);
1137 link = ERR_PTR(len);
1139 link[min(len, PATH_MAX-1)] = 0;
1141 nd_set_link(nd, link);
1147 * v9fs_vfs_put_link - release a symlink path
1148 * @dentry: dentry for symlink
1155 v9fs_vfs_put_link(struct dentry *dentry, struct nameidata *nd, void *p)
1157 char *s = nd_get_link(nd);
1159 P9_DPRINTK(P9_DEBUG_VFS, " %s %s\n", dentry->d_name.name,
1160 IS_ERR(s) ? "<error>" : s);
1166 * v9fs_vfs_mkspecial - create a special file
1167 * @dir: inode to create special file in
1168 * @dentry: dentry to create
1169 * @mode: mode to create special file
1170 * @extension: 9p2000.u format extension string representing special file
1174 static int v9fs_vfs_mkspecial(struct inode *dir, struct dentry *dentry,
1175 int mode, const char *extension)
1178 struct v9fs_session_info *v9ses;
1181 v9ses = v9fs_inode2v9ses(dir);
1182 if (!v9fs_proto_dotu(v9ses)) {
1183 P9_DPRINTK(P9_DEBUG_ERROR, "not extended\n");
1187 perm = unixmode2p9mode(v9ses, mode);
1188 fid = v9fs_create(v9ses, dir, dentry, (char *) extension, perm,
1191 return PTR_ERR(fid);
1193 p9_client_clunk(fid);
1198 * v9fs_vfs_symlink - helper function to create symlinks
1199 * @dir: directory inode containing symlink
1200 * @dentry: dentry for symlink
1201 * @symname: symlink data
1203 * See Also: 9P2000.u RFC for more information
1208 v9fs_vfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname)
1210 P9_DPRINTK(P9_DEBUG_VFS, " %lu,%s,%s\n", dir->i_ino,
1211 dentry->d_name.name, symname);
1213 return v9fs_vfs_mkspecial(dir, dentry, S_IFLNK, symname);
1217 * v9fs_vfs_link - create a hardlink
1218 * @old_dentry: dentry for file to link to
1219 * @dir: inode destination for new link
1220 * @dentry: dentry for link
1225 v9fs_vfs_link(struct dentry *old_dentry, struct inode *dir,
1226 struct dentry *dentry)
1229 struct p9_fid *oldfid;
1232 P9_DPRINTK(P9_DEBUG_VFS,
1233 " %lu,%s,%s\n", dir->i_ino, dentry->d_name.name,
1234 old_dentry->d_name.name);
1236 oldfid = v9fs_fid_clone(old_dentry);
1238 return PTR_ERR(oldfid);
1241 if (unlikely(!name)) {
1246 sprintf(name, "%d\n", oldfid->fid);
1247 retval = v9fs_vfs_mkspecial(dir, dentry, P9_DMLINK, name);
1251 p9_client_clunk(oldfid);
1256 * v9fs_vfs_mknod - create a special file
1257 * @dir: inode destination for new link
1258 * @dentry: dentry for file
1259 * @mode: mode for creation
1260 * @rdev: device associated with special file
1265 v9fs_vfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t rdev)
1270 P9_DPRINTK(P9_DEBUG_VFS,
1271 " %lu,%s mode: %x MAJOR: %u MINOR: %u\n", dir->i_ino,
1272 dentry->d_name.name, mode, MAJOR(rdev), MINOR(rdev));
1274 if (!new_valid_dev(rdev))
1280 /* build extension */
1282 sprintf(name, "b %u %u", MAJOR(rdev), MINOR(rdev));
1283 else if (S_ISCHR(mode))
1284 sprintf(name, "c %u %u", MAJOR(rdev), MINOR(rdev));
1285 else if (S_ISFIFO(mode))
1287 else if (S_ISSOCK(mode))
1294 retval = v9fs_vfs_mkspecial(dir, dentry, mode, name);
1300 static const struct inode_operations v9fs_dir_inode_operations_dotu = {
1301 .create = v9fs_vfs_create,
1302 .lookup = v9fs_vfs_lookup,
1303 .symlink = v9fs_vfs_symlink,
1304 .link = v9fs_vfs_link,
1305 .unlink = v9fs_vfs_unlink,
1306 .mkdir = v9fs_vfs_mkdir,
1307 .rmdir = v9fs_vfs_rmdir,
1308 .mknod = v9fs_vfs_mknod,
1309 .rename = v9fs_vfs_rename,
1310 .getattr = v9fs_vfs_getattr,
1311 .setattr = v9fs_vfs_setattr,
1314 static const struct inode_operations v9fs_dir_inode_operations = {
1315 .create = v9fs_vfs_create,
1316 .lookup = v9fs_vfs_lookup,
1317 .unlink = v9fs_vfs_unlink,
1318 .mkdir = v9fs_vfs_mkdir,
1319 .rmdir = v9fs_vfs_rmdir,
1320 .mknod = v9fs_vfs_mknod,
1321 .rename = v9fs_vfs_rename,
1322 .getattr = v9fs_vfs_getattr,
1323 .setattr = v9fs_vfs_setattr,
1326 static const struct inode_operations v9fs_file_inode_operations = {
1327 .getattr = v9fs_vfs_getattr,
1328 .setattr = v9fs_vfs_setattr,
1331 static const struct inode_operations v9fs_symlink_inode_operations = {
1332 .readlink = generic_readlink,
1333 .follow_link = v9fs_vfs_follow_link,
1334 .put_link = v9fs_vfs_put_link,
1335 .getattr = v9fs_vfs_getattr,
1336 .setattr = v9fs_vfs_setattr,