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 #ifdef HAVE_LOOKUP_NAMEIDATA
147 zpl_root_lookup(struct inode *dip, struct dentry *dentry, struct nameidata *nd)
149 zpl_root_lookup(struct inode *dip, struct dentry *dentry, unsigned int flags)
157 error = -zfsctl_root_lookup(dip, dname(dentry), &ip, 0, cr, NULL, NULL);
158 ASSERT3S(error, <=, 0);
162 if (error == -ENOENT)
163 return d_splice_alias(NULL, dentry);
165 return ERR_PTR(error);
168 return d_splice_alias(ip, dentry);
172 * The '.zfs' control directory file and inode operations.
174 const struct file_operations zpl_fops_root = {
175 .open = zpl_common_open,
176 .llseek = generic_file_llseek,
177 .read = generic_read_dir,
178 .readdir = zpl_root_readdir,
181 const struct inode_operations zpl_ops_root = {
182 .lookup = zpl_root_lookup,
183 .getattr = zpl_root_getattr,
186 static struct dentry *
187 #ifdef HAVE_LOOKUP_NAMEIDATA
188 zpl_snapdir_lookup(struct inode *dip, struct dentry *dentry,
189 struct nameidata *nd)
191 zpl_snapdir_lookup(struct inode *dip, struct dentry *dentry,
201 error = -zfsctl_snapdir_lookup(dip, dname(dentry), &ip,
203 ASSERT3S(error, <=, 0);
207 if (error == -ENOENT)
208 return d_splice_alias(NULL, dentry);
210 return ERR_PTR(error);
214 * Auto mounting of snapshots is only supported for 2.6.37 and
215 * newer kernels. Prior to this kernel the ops->follow_link()
216 * callback was used as a hack to trigger the mount. The
217 * resulting vfsmount was then explicitly grafted in to the
218 * name space. While it might be possible to add compatibility
219 * code to accomplish this it would require considerable care.
221 #ifdef HAVE_AUTOMOUNT
222 dentry->d_op = &zpl_dops_snapdirs;
223 #endif /* HAVE_AUTOMOUNT */
225 return d_splice_alias(ip, dentry);
230 zpl_snapdir_readdir(struct file *filp, void *dirent, filldir_t filldir)
232 struct dentry *dentry = filp->f_path.dentry;
233 struct inode *dip = dentry->d_inode;
234 zfs_sb_t *zsb = ITOZSB(dip);
235 char snapname[MAXNAMELEN];
237 boolean_t case_conflict;
242 cookie = filp->f_pos;
243 switch (filp->f_pos) {
245 error = filldir(dirent, ".", 1, 0, dip->i_ino, DT_DIR);
252 error = filldir(dirent, "..", 2, 1, parent_ino(dentry), DT_DIR);
260 error = -dmu_snapshot_list_next(zsb->z_os, MAXNAMELEN,
261 snapname, &id, &cookie, &case_conflict);
265 error = filldir(dirent, snapname, strlen(snapname),
266 filp->f_pos, ZFSCTL_INO_SHARES - id, DT_DIR);
270 filp->f_pos = cookie;
276 if (error == -ENOENT)
283 zpl_snapdir_rename(struct inode *sdip, struct dentry *sdentry,
284 struct inode *tdip, struct dentry *tdentry)
290 error = -zfsctl_snapdir_rename(sdip, dname(sdentry),
291 tdip, dname(tdentry), cr, 0);
292 ASSERT3S(error, <=, 0);
299 zpl_snapdir_rmdir(struct inode *dip, struct dentry *dentry)
305 error = -zfsctl_snapdir_remove(dip, dname(dentry), cr, 0);
306 ASSERT3S(error, <=, 0);
313 zpl_snapdir_mkdir(struct inode *dip, struct dentry *dentry, zpl_umode_t mode)
321 vap = kmem_zalloc(sizeof(vattr_t), KM_SLEEP);
322 zpl_vap_init(vap, dip, dentry, mode | S_IFDIR, cr);
324 error = -zfsctl_snapdir_mkdir(dip, dname(dentry), vap, &ip, cr, 0);
326 #ifdef HAVE_AUTOMOUNT
327 dentry->d_op = &zpl_dops_snapdirs;
328 #endif /* HAVE_AUTOMOUNT */
329 d_instantiate(dentry, ip);
332 kmem_free(vap, sizeof(vattr_t));
333 ASSERT3S(error, <=, 0);
339 #ifdef HAVE_AUTOMOUNT
340 static struct vfsmount *
341 zpl_snapdir_automount(struct path *path)
343 struct dentry *dentry = path->dentry;
347 * We must briefly disable automounts for this dentry because the
348 * user space mount utility will trigger another lookup on this
349 * directory. That will result in zpl_snapdir_automount() being
350 * called repeatedly. The DCACHE_NEED_AUTOMOUNT flag can be
351 * safely reset once the mount completes.
353 dentry->d_flags &= ~DCACHE_NEED_AUTOMOUNT;
354 error = -zfsctl_mount_snapshot(path, 0);
355 dentry->d_flags |= DCACHE_NEED_AUTOMOUNT;
357 return ERR_PTR(error);
360 * Ensure path->dentry points to the dentry for the root of the
361 * newly-mounted snapshot, otherwise this function may be called
362 * repeatedly which can lead to an incorrect ELOOP error return.
367 * Rather than returning the new vfsmount for the snapshot we must
368 * return NULL to indicate a mount collision. This is done because
369 * the user space mount calls do_add_mount() which adds the vfsmount
370 * to the name space. If we returned the new mount here it would be
371 * added again to the vfsmount list resulting in list corruption.
375 #endif /* HAVE_AUTOMOUNT */
378 * Get snapshot directory attributes.
382 zpl_snapdir_getattr(struct vfsmount *mnt, struct dentry *dentry,
385 zfs_sb_t *zsb = ITOZSB(dentry->d_inode);
389 error = simple_getattr(mnt, dentry, stat);
390 stat->nlink = stat->size = avl_numnodes(&zsb->z_ctldir_snaps) + 2;
391 stat->ctime = stat->mtime = dmu_objset_snap_cmtime(zsb->z_os);
392 stat->atime = CURRENT_TIME;
399 * The '.zfs/snapshot' directory file operations. These mainly control
400 * generating the list of available snapshots when doing an 'ls' in the
401 * directory. See zpl_snapdir_readdir().
403 const struct file_operations zpl_fops_snapdir = {
404 .open = zpl_common_open,
405 .llseek = generic_file_llseek,
406 .read = generic_read_dir,
407 .readdir = zpl_snapdir_readdir,
411 * The '.zfs/snapshot' directory inode operations. These mainly control
412 * creating an inode for a snapshot directory and initializing the needed
413 * infrastructure to automount the snapshot. See zpl_snapdir_lookup().
415 const struct inode_operations zpl_ops_snapdir = {
416 .lookup = zpl_snapdir_lookup,
417 .getattr = zpl_snapdir_getattr,
418 .rename = zpl_snapdir_rename,
419 .rmdir = zpl_snapdir_rmdir,
420 .mkdir = zpl_snapdir_mkdir,
423 #ifdef HAVE_AUTOMOUNT
424 const struct dentry_operations zpl_dops_snapdirs = {
425 .d_automount = zpl_snapdir_automount,
427 #endif /* HAVE_AUTOMOUNT */
429 static struct dentry *
430 #ifdef HAVE_LOOKUP_NAMEIDATA
431 zpl_shares_lookup(struct inode *dip, struct dentry *dentry,
432 struct nameidata *nd)
434 zpl_shares_lookup(struct inode *dip, struct dentry *dentry,
439 struct inode *ip = NULL;
443 error = -zfsctl_shares_lookup(dip, dname(dentry), &ip,
445 ASSERT3S(error, <=, 0);
449 if (error == -ENOENT)
450 return d_splice_alias(NULL, dentry);
452 return ERR_PTR(error);
455 return d_splice_alias(ip, dentry);
460 zpl_shares_readdir(struct file *filp, void *dirent, filldir_t filldir)
463 struct dentry *dentry = filp->f_path.dentry;
464 struct inode *ip = dentry->d_inode;
465 zfs_sb_t *zsb = ITOZSB(ip);
471 if (zsb->z_shares_dir == 0) {
472 error = zpl_common_readdir(filp, dirent, filldir);
477 error = -zfs_zget(zsb, zsb->z_shares_dir, &dzp);
484 error = -zfs_readdir(ZTOI(dzp), dirent, filldir, &filp->f_pos, cr);
489 ASSERT3S(error, <=, 0);
496 zpl_shares_getattr(struct vfsmount *mnt, struct dentry *dentry,
499 struct inode *ip = dentry->d_inode;
500 zfs_sb_t *zsb = ITOZSB(ip);
506 if (zsb->z_shares_dir == 0) {
507 error = simple_getattr(mnt, dentry, stat);
508 stat->nlink = stat->size = 2;
509 stat->atime = CURRENT_TIME;
514 error = -zfs_zget(zsb, zsb->z_shares_dir, &dzp);
516 error = -zfs_getattr_fast(dentry->d_inode, stat);
520 ASSERT3S(error, <=, 0);
526 * The '.zfs/shares' directory file operations.
528 const struct file_operations zpl_fops_shares = {
529 .open = zpl_common_open,
530 .llseek = generic_file_llseek,
531 .read = generic_read_dir,
532 .readdir = zpl_shares_readdir,
536 * The '.zfs/shares' directory inode operations.
538 const struct inode_operations zpl_ops_shares = {
539 .lookup = zpl_shares_lookup,
540 .getattr = zpl_shares_getattr,