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 * Get root directory contents.
53 zpl_root_iterate(struct file *filp, struct dir_context *ctx)
55 zfs_sb_t *zsb = ITOZSB(filp->f_path.dentry->d_inode);
60 if (!dir_emit_dots(filp, ctx))
64 if (!dir_emit(ctx, ZFS_SNAPDIR_NAME, strlen(ZFS_SNAPDIR_NAME),
65 ZFSCTL_INO_SNAPDIR, DT_DIR))
72 if (!dir_emit(ctx, ZFS_SHAREDIR_NAME, strlen(ZFS_SHAREDIR_NAME),
73 ZFSCTL_INO_SHARES, DT_DIR))
84 #if !defined(HAVE_VFS_ITERATE)
86 zpl_root_readdir(struct file *filp, void *dirent, filldir_t filldir)
88 struct dir_context ctx = DIR_CONTEXT_INIT(dirent, filldir, filp->f_pos);
91 error = zpl_root_iterate(filp, &ctx);
92 filp->f_pos = ctx.pos;
96 #endif /* HAVE_VFS_ITERATE */
99 * Get root directory attributes.
103 zpl_root_getattr(struct vfsmount *mnt, struct dentry *dentry,
108 error = simple_getattr(mnt, dentry, stat);
109 stat->atime = CURRENT_TIME;
114 static struct dentry *
115 #ifdef HAVE_LOOKUP_NAMEIDATA
116 zpl_root_lookup(struct inode *dip, struct dentry *dentry, struct nameidata *nd)
118 zpl_root_lookup(struct inode *dip, struct dentry *dentry, unsigned int flags)
126 error = -zfsctl_root_lookup(dip, dname(dentry), &ip, 0, cr, NULL, NULL);
127 ASSERT3S(error, <=, 0);
131 if (error == -ENOENT)
132 return d_splice_alias(NULL, dentry);
134 return ERR_PTR(error);
137 return d_splice_alias(ip, dentry);
141 * The '.zfs' control directory file and inode operations.
143 const struct file_operations zpl_fops_root = {
144 .open = zpl_common_open,
145 .llseek = generic_file_llseek,
146 .read = generic_read_dir,
147 #ifdef HAVE_VFS_ITERATE
148 .iterate = zpl_root_iterate,
150 .readdir = zpl_root_readdir,
154 const struct inode_operations zpl_ops_root = {
155 .lookup = zpl_root_lookup,
156 .getattr = zpl_root_getattr,
159 #ifdef HAVE_AUTOMOUNT
160 static struct vfsmount *
161 zpl_snapdir_automount(struct path *path)
163 struct dentry *dentry = path->dentry;
167 * We must briefly disable automounts for this dentry because the
168 * user space mount utility will trigger another lookup on this
169 * directory. That will result in zpl_snapdir_automount() being
170 * called repeatedly. The DCACHE_NEED_AUTOMOUNT flag can be
171 * safely reset once the mount completes.
173 dentry->d_flags &= ~DCACHE_NEED_AUTOMOUNT;
174 error = -zfsctl_mount_snapshot(path, 0);
175 dentry->d_flags |= DCACHE_NEED_AUTOMOUNT;
177 return ERR_PTR(error);
180 * Rather than returning the new vfsmount for the snapshot we must
181 * return NULL to indicate a mount collision. This is done because
182 * the user space mount calls do_add_mount() which adds the vfsmount
183 * to the name space. If we returned the new mount here it would be
184 * added again to the vfsmount list resulting in list corruption.
188 #endif /* HAVE_AUTOMOUNT */
191 * Revalidate any dentry in the snapshot directory on lookup, since a snapshot
192 * having the same name have been created or destroyed since it was cached.
195 #ifdef HAVE_D_REVALIDATE_NAMEIDATA
196 zpl_snapdir_revalidate(struct dentry *dentry, struct nameidata *i)
198 zpl_snapdir_revalidate(struct dentry *dentry, unsigned int flags)
204 dentry_operations_t zpl_dops_snapdirs = {
206 * Auto mounting of snapshots is only supported for 2.6.37 and
207 * newer kernels. Prior to this kernel the ops->follow_link()
208 * callback was used as a hack to trigger the mount. The
209 * resulting vfsmount was then explicitly grafted in to the
210 * name space. While it might be possible to add compatibility
211 * code to accomplish this it would require considerable care.
213 #ifdef HAVE_AUTOMOUNT
214 .d_automount = zpl_snapdir_automount,
215 #endif /* HAVE_AUTOMOUNT */
216 .d_revalidate = zpl_snapdir_revalidate,
219 static struct dentry *
220 #ifdef HAVE_LOOKUP_NAMEIDATA
221 zpl_snapdir_lookup(struct inode *dip, struct dentry *dentry,
222 struct nameidata *nd)
224 zpl_snapdir_lookup(struct inode *dip, struct dentry *dentry,
230 struct inode *ip = NULL;
234 error = -zfsctl_snapdir_lookup(dip, dname(dentry), &ip,
236 ASSERT3S(error, <=, 0);
239 if (error && error != -ENOENT)
240 return ERR_PTR(error);
242 ASSERT(error == 0 || ip == NULL);
243 d_clear_d_op(dentry);
244 d_set_d_op(dentry, &zpl_dops_snapdirs);
246 return d_splice_alias(ip, dentry);
250 zpl_snapdir_iterate(struct file *filp, struct dir_context *ctx)
252 zfs_sb_t *zsb = ITOZSB(filp->f_path.dentry->d_inode);
253 char snapname[MAXNAMELEN];
254 boolean_t case_conflict;
260 if (!dir_emit_dots(filp, ctx))
264 error = -dmu_snapshot_list_next(zsb->z_os, MAXNAMELEN,
265 snapname, &id, &(ctx->pos), &case_conflict);
269 if (!dir_emit(ctx, snapname, strlen(snapname),
270 ZFSCTL_INO_SHARES - id, DT_DIR))
276 if (error == -ENOENT)
282 #if !defined(HAVE_VFS_ITERATE)
284 zpl_snapdir_readdir(struct file *filp, void *dirent, filldir_t filldir)
286 struct dir_context ctx = DIR_CONTEXT_INIT(dirent, filldir, filp->f_pos);
289 error = zpl_snapdir_iterate(filp, &ctx);
290 filp->f_pos = ctx.pos;
294 #endif /* HAVE_VFS_ITERATE */
297 zpl_snapdir_rename(struct inode *sdip, struct dentry *sdentry,
298 struct inode *tdip, struct dentry *tdentry)
304 error = -zfsctl_snapdir_rename(sdip, dname(sdentry),
305 tdip, dname(tdentry), cr, 0);
306 ASSERT3S(error, <=, 0);
313 zpl_snapdir_rmdir(struct inode *dip, struct dentry *dentry)
319 error = -zfsctl_snapdir_remove(dip, dname(dentry), cr, 0);
320 ASSERT3S(error, <=, 0);
327 zpl_snapdir_mkdir(struct inode *dip, struct dentry *dentry, zpl_umode_t mode)
335 vap = kmem_zalloc(sizeof(vattr_t), KM_SLEEP);
336 zpl_vap_init(vap, dip, mode | S_IFDIR, cr);
338 error = -zfsctl_snapdir_mkdir(dip, dname(dentry), vap, &ip, cr, 0);
340 d_clear_d_op(dentry);
341 d_set_d_op(dentry, &zpl_dops_snapdirs);
342 d_instantiate(dentry, ip);
345 kmem_free(vap, sizeof(vattr_t));
346 ASSERT3S(error, <=, 0);
353 * Get snapshot directory attributes.
357 zpl_snapdir_getattr(struct vfsmount *mnt, struct dentry *dentry,
360 zfs_sb_t *zsb = ITOZSB(dentry->d_inode);
364 error = simple_getattr(mnt, dentry, stat);
365 stat->nlink = stat->size = avl_numnodes(&zsb->z_ctldir_snaps) + 2;
366 stat->ctime = stat->mtime = dmu_objset_snap_cmtime(zsb->z_os);
367 stat->atime = CURRENT_TIME;
374 * The '.zfs/snapshot' directory file operations. These mainly control
375 * generating the list of available snapshots when doing an 'ls' in the
376 * directory. See zpl_snapdir_readdir().
378 const struct file_operations zpl_fops_snapdir = {
379 .open = zpl_common_open,
380 .llseek = generic_file_llseek,
381 .read = generic_read_dir,
382 #ifdef HAVE_VFS_ITERATE
383 .iterate = zpl_snapdir_iterate,
385 .readdir = zpl_snapdir_readdir,
391 * The '.zfs/snapshot' directory inode operations. These mainly control
392 * creating an inode for a snapshot directory and initializing the needed
393 * infrastructure to automount the snapshot. See zpl_snapdir_lookup().
395 const struct inode_operations zpl_ops_snapdir = {
396 .lookup = zpl_snapdir_lookup,
397 .getattr = zpl_snapdir_getattr,
398 .rename = zpl_snapdir_rename,
399 .rmdir = zpl_snapdir_rmdir,
400 .mkdir = zpl_snapdir_mkdir,
403 static struct dentry *
404 #ifdef HAVE_LOOKUP_NAMEIDATA
405 zpl_shares_lookup(struct inode *dip, struct dentry *dentry,
406 struct nameidata *nd)
408 zpl_shares_lookup(struct inode *dip, struct dentry *dentry,
413 struct inode *ip = NULL;
417 error = -zfsctl_shares_lookup(dip, dname(dentry), &ip,
419 ASSERT3S(error, <=, 0);
423 if (error == -ENOENT)
424 return d_splice_alias(NULL, dentry);
426 return ERR_PTR(error);
429 return d_splice_alias(ip, dentry);
433 zpl_shares_iterate(struct file *filp, struct dir_context *ctx)
436 zfs_sb_t *zsb = ITOZSB(filp->f_path.dentry->d_inode);
442 if (zsb->z_shares_dir == 0) {
443 dir_emit_dots(filp, ctx);
447 error = -zfs_zget(zsb, zsb->z_shares_dir, &dzp);
452 error = -zfs_readdir(ZTOI(dzp), ctx, cr);
458 ASSERT3S(error, <=, 0);
463 #if !defined(HAVE_VFS_ITERATE)
465 zpl_shares_readdir(struct file *filp, void *dirent, filldir_t filldir)
467 struct dir_context ctx = DIR_CONTEXT_INIT(dirent, filldir, filp->f_pos);
470 error = zpl_shares_iterate(filp, &ctx);
471 filp->f_pos = ctx.pos;
475 #endif /* HAVE_VFS_ITERATE */
479 zpl_shares_getattr(struct vfsmount *mnt, struct dentry *dentry,
482 struct inode *ip = dentry->d_inode;
483 zfs_sb_t *zsb = ITOZSB(ip);
489 if (zsb->z_shares_dir == 0) {
490 error = simple_getattr(mnt, dentry, stat);
491 stat->nlink = stat->size = 2;
492 stat->atime = CURRENT_TIME;
497 error = -zfs_zget(zsb, zsb->z_shares_dir, &dzp);
499 error = -zfs_getattr_fast(dentry->d_inode, stat);
503 ASSERT3S(error, <=, 0);
509 * The '.zfs/shares' directory file operations.
511 const struct file_operations zpl_fops_shares = {
512 .open = zpl_common_open,
513 .llseek = generic_file_llseek,
514 .read = generic_read_dir,
515 #ifdef HAVE_VFS_ITERATE
516 .iterate = zpl_shares_iterate,
518 .readdir = zpl_shares_readdir,
524 * The '.zfs/shares' directory inode operations.
526 const struct inode_operations zpl_ops_shares = {
527 .lookup = zpl_shares_lookup,
528 .getattr = zpl_shares_getattr,