4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
22 * Copyright (C) 2011 Lawrence Livermore National Security, LLC.
23 * Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER).
25 * Rewritten for Linux by:
26 * Rohan Puri <rohan.puri15@gmail.com>
27 * Brian Behlendorf <behlendorf1@llnl.gov>
30 #include <sys/zfs_vfsops.h>
31 #include <sys/zfs_vnops.h>
32 #include <sys/zfs_znode.h>
33 #include <sys/zfs_ctldir.h>
37 * Common open routine. Disallow any write access.
41 zpl_common_open(struct inode *ip, struct file *filp)
43 if (filp->f_mode & FMODE_WRITE)
46 return generic_file_open(ip, filp);
50 zpl_common_readdir(struct file *filp, void *dirent, filldir_t filldir)
52 struct dentry *dentry = filp->f_path.dentry;
53 struct inode *ip = dentry->d_inode;
56 switch (filp->f_pos) {
58 error = filldir(dirent, ".", 1, 0, ip->i_ino, DT_DIR);
65 error = filldir(dirent, "..", 2, 1, parent_ino(dentry), DT_DIR);
79 * Get root directory contents.
82 zpl_root_readdir(struct file *filp, void *dirent, filldir_t filldir)
84 struct dentry *dentry = filp->f_path.dentry;
85 struct inode *ip = dentry->d_inode;
86 zfs_sb_t *zsb = ITOZSB(ip);
91 switch (filp->f_pos) {
93 error = filldir(dirent, ".", 1, 0, ip->i_ino, DT_DIR);
100 error = filldir(dirent, "..", 2, 1, parent_ino(dentry), DT_DIR);
107 error = filldir(dirent, ZFS_SNAPDIR_NAME,
108 strlen(ZFS_SNAPDIR_NAME), 2, ZFSCTL_INO_SNAPDIR, DT_DIR);
115 error = filldir(dirent, ZFS_SHAREDIR_NAME,
116 strlen(ZFS_SHAREDIR_NAME), 3, ZFSCTL_INO_SHARES, DT_DIR);
130 * Get root directory attributes.
134 zpl_root_getattr(struct vfsmount *mnt, struct dentry *dentry,
139 error = simple_getattr(mnt, dentry, stat);
140 stat->atime = CURRENT_TIME;
145 static struct dentry *
146 zpl_root_lookup(struct inode *dip, struct dentry *dentry, struct nameidata *nd)
153 error = -zfsctl_root_lookup(dip, dname(dentry), &ip, 0, cr, NULL, NULL);
154 ASSERT3S(error, <=, 0);
158 if (error == -ENOENT)
159 return d_splice_alias(NULL, dentry);
161 return ERR_PTR(error);
164 return d_splice_alias(ip, dentry);
168 * The '.zfs' control directory file and inode operations.
170 const struct file_operations zpl_fops_root = {
171 .open = zpl_common_open,
172 .llseek = generic_file_llseek,
173 .read = generic_read_dir,
174 .readdir = zpl_root_readdir,
177 const struct inode_operations zpl_ops_root = {
178 .lookup = zpl_root_lookup,
179 .getattr = zpl_root_getattr,
182 static struct dentry *
183 zpl_snapdir_lookup(struct inode *dip, struct dentry *dentry,
184 struct nameidata *nd)
191 error = -zfsctl_snapdir_lookup(dip, dname(dentry), &ip,
193 ASSERT3S(error, <=, 0);
197 if (error == -ENOENT)
198 return d_splice_alias(NULL, dentry);
200 return ERR_PTR(error);
204 * Auto mounting of snapshots is only supported for 2.6.37 and
205 * newer kernels. Prior to this kernel the ops->follow_link()
206 * callback was used as a hack to trigger the mount. The
207 * resulting vfsmount was then explicitly grafted in to the
208 * name space. While it might be possible to add compatibility
209 * code to accomplish this it would require considerable care.
211 #ifdef HAVE_AUTOMOUNT
212 dentry->d_op = &zpl_dops_snapdirs;
213 #endif /* HAVE_AUTOMOUNT */
215 return d_splice_alias(ip, dentry);
220 zpl_snapdir_readdir(struct file *filp, void *dirent, filldir_t filldir)
222 struct dentry *dentry = filp->f_path.dentry;
223 struct inode *dip = dentry->d_inode;
224 zfs_sb_t *zsb = ITOZSB(dip);
225 char snapname[MAXNAMELEN];
227 boolean_t case_conflict;
232 cookie = filp->f_pos;
233 switch (filp->f_pos) {
235 error = filldir(dirent, ".", 1, 0, dip->i_ino, DT_DIR);
242 error = filldir(dirent, "..", 2, 1, parent_ino(dentry), DT_DIR);
250 error = -dmu_snapshot_list_next(zsb->z_os, MAXNAMELEN,
251 snapname, &id, &cookie, &case_conflict);
255 error = filldir(dirent, snapname, strlen(snapname),
256 filp->f_pos, ZFSCTL_INO_SHARES - id, DT_DIR);
260 filp->f_pos = cookie;
266 if (error == -ENOENT)
273 zpl_snapdir_rename(struct inode *sdip, struct dentry *sdentry,
274 struct inode *tdip, struct dentry *tdentry)
280 error = -zfsctl_snapdir_rename(sdip, dname(sdentry),
281 tdip, dname(tdentry), cr, 0);
282 ASSERT3S(error, <=, 0);
289 zpl_snapdir_rmdir(struct inode *dip, struct dentry *dentry)
295 error = -zfsctl_snapdir_remove(dip, dname(dentry), cr, 0);
296 ASSERT3S(error, <=, 0);
303 zpl_snapdir_mkdir(struct inode *dip, struct dentry *dentry, zpl_umode_t mode)
311 vap = kmem_zalloc(sizeof(vattr_t), KM_SLEEP);
312 zpl_vap_init(vap, dip, dentry, mode | S_IFDIR, cr);
314 error = -zfsctl_snapdir_mkdir(dip, dname(dentry), vap, &ip, cr, 0);
316 #ifdef HAVE_AUTOMOUNT
317 dentry->d_op = &zpl_dops_snapdirs;
318 #endif /* HAVE_AUTOMOUNT */
319 d_instantiate(dentry, ip);
322 kmem_free(vap, sizeof(vattr_t));
323 ASSERT3S(error, <=, 0);
329 #ifdef HAVE_AUTOMOUNT
330 static struct vfsmount *
331 zpl_snapdir_automount(struct path *path)
333 struct dentry *dentry = path->dentry;
337 * We must briefly disable automounts for this dentry because the
338 * user space mount utility will trigger another lookup on this
339 * directory. That will result in zpl_snapdir_automount() being
340 * called repeatedly. The DCACHE_NEED_AUTOMOUNT flag can be
341 * safely reset once the mount completes.
343 dentry->d_flags &= ~DCACHE_NEED_AUTOMOUNT;
344 error = -zfsctl_mount_snapshot(path, 0);
345 dentry->d_flags |= DCACHE_NEED_AUTOMOUNT;
347 return ERR_PTR(error);
350 * Rather than returning the new vfsmount for the snapshot we must
351 * return NULL to indicate a mount collision. This is done because
352 * the user space mount calls do_add_mount() which adds the vfsmount
353 * to the name space. If we returned the new mount here it would be
354 * added again to the vfsmount list resulting in list corruption.
358 #endif /* HAVE_AUTOMOUNT */
361 * Get snapshot directory attributes.
365 zpl_snapdir_getattr(struct vfsmount *mnt, struct dentry *dentry,
368 zfs_sb_t *zsb = ITOZSB(dentry->d_inode);
372 error = simple_getattr(mnt, dentry, stat);
373 stat->nlink = stat->size = avl_numnodes(&zsb->z_ctldir_snaps) + 2;
374 stat->ctime = stat->mtime = dmu_objset_snap_cmtime(zsb->z_os);
375 stat->atime = CURRENT_TIME;
382 * The '.zfs/snapshot' directory file operations. These mainly control
383 * generating the list of available snapshots when doing an 'ls' in the
384 * directory. See zpl_snapdir_readdir().
386 const struct file_operations zpl_fops_snapdir = {
387 .open = zpl_common_open,
388 .llseek = generic_file_llseek,
389 .read = generic_read_dir,
390 .readdir = zpl_snapdir_readdir,
394 * The '.zfs/snapshot' directory inode operations. These mainly control
395 * creating an inode for a snapshot directory and initializing the needed
396 * infrastructure to automount the snapshot. See zpl_snapdir_lookup().
398 const struct inode_operations zpl_ops_snapdir = {
399 .lookup = zpl_snapdir_lookup,
400 .getattr = zpl_snapdir_getattr,
401 .rename = zpl_snapdir_rename,
402 .rmdir = zpl_snapdir_rmdir,
403 .mkdir = zpl_snapdir_mkdir,
406 #ifdef HAVE_AUTOMOUNT
407 const struct dentry_operations zpl_dops_snapdirs = {
408 .d_automount = zpl_snapdir_automount,
410 #endif /* HAVE_AUTOMOUNT */
412 static struct dentry *
413 zpl_shares_lookup(struct inode *dip, struct dentry *dentry,
414 struct nameidata *nd)
417 struct inode *ip = NULL;
421 error = -zfsctl_shares_lookup(dip, dname(dentry), &ip,
423 ASSERT3S(error, <=, 0);
427 if (error == -ENOENT)
428 return d_splice_alias(NULL, dentry);
430 return ERR_PTR(error);
433 return d_splice_alias(ip, dentry);
438 zpl_shares_readdir(struct file *filp, void *dirent, filldir_t filldir)
441 struct dentry *dentry = filp->f_path.dentry;
442 struct inode *ip = dentry->d_inode;
443 zfs_sb_t *zsb = ITOZSB(ip);
449 if (zsb->z_shares_dir == 0) {
450 error = zpl_common_readdir(filp, dirent, filldir);
455 error = -zfs_zget(zsb, zsb->z_shares_dir, &dzp);
462 error = -zfs_readdir(ZTOI(dzp), dirent, filldir, &filp->f_pos, cr);
467 ASSERT3S(error, <=, 0);
474 zpl_shares_getattr(struct vfsmount *mnt, struct dentry *dentry,
477 struct inode *ip = dentry->d_inode;
478 zfs_sb_t *zsb = ITOZSB(ip);
484 if (zsb->z_shares_dir == 0) {
485 error = simple_getattr(mnt, dentry, stat);
486 stat->nlink = stat->size = 2;
487 stat->atime = CURRENT_TIME;
492 error = -zfs_zget(zsb, zsb->z_shares_dir, &dzp);
494 error = -zfs_getattr_fast(dentry->d_inode, stat);
498 ASSERT3S(error, <=, 0);
504 * The '.zfs/shares' directory file operations.
506 const struct file_operations zpl_fops_shares = {
507 .open = zpl_common_open,
508 .llseek = generic_file_llseek,
509 .read = generic_read_dir,
510 .readdir = zpl_shares_readdir,
514 * The '.zfs/shares' directory inode operations.
516 const struct inode_operations zpl_ops_shares = {
517 .lookup = zpl_shares_lookup,
518 .getattr = zpl_shares_getattr,