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.
26 #include <sys/zfs_vfsops.h>
27 #include <sys/zfs_vnops.h>
28 #include <sys/zfs_znode.h>
29 #include <sys/zfs_ctldir.h>
34 zpl_inode_alloc(struct super_block *sb)
38 VERIFY3S(zfs_inode_alloc(sb, &ip), ==, 0);
45 zpl_inode_destroy(struct inode *ip)
47 ASSERT(atomic_read(&ip->i_count) == 0);
48 zfs_inode_destroy(ip);
52 * When ->drop_inode() is called its return value indicates if the
53 * inode should be evicted from the inode cache. If the inode is
54 * unhashed and has no links the default policy is to evict it
57 * Prior to 2.6.36 this eviction was accomplished by the vfs calling
58 * ->delete_inode(). It was ->delete_inode()'s responsibility to
59 * truncate the inode pages and call clear_inode(). The call to
60 * clear_inode() synchronously invalidates all the buffers and
61 * calls ->clear_inode(). It was ->clear_inode()'s responsibility
62 * to cleanup and filesystem specific data before freeing the inode.
64 * This elaborate mechanism was replaced by ->evict_inode() which
65 * does the job of both ->delete_inode() and ->clear_inode(). It
66 * will be called exactly once, and when it returns the inode must
67 * be in a state where it can simply be freed.i
69 * The ->evict_inode() callback must minimally truncate the inode pages,
70 * and call clear_inode(). For 2.6.35 and later kernels this will
71 * simply update the inode state, with the sync occurring before the
72 * truncate in evict(). For earlier kernels clear_inode() maps to
73 * end_writeback() which is responsible for completing all outstanding
74 * write back. In either case, once this is done it is safe to cleanup
75 * any remaining inode specific data via zfs_inactive().
76 * remaining filesystem specific data.
78 #ifdef HAVE_EVICT_INODE
80 zpl_evict_inode(struct inode *ip)
82 truncate_setsize(ip, 0);
90 zpl_clear_inode(struct inode *ip)
96 zpl_inode_delete(struct inode *ip)
98 truncate_setsize(ip, 0);
102 #endif /* HAVE_EVICT_INODE */
105 zpl_put_super(struct super_block *sb)
109 error = -zfs_umount(sb);
110 ASSERT3S(error, <=, 0);
114 zpl_sync_fs(struct super_block *sb, int wait)
120 error = -zfs_sync(sb, wait, cr);
122 ASSERT3S(error, <=, 0);
128 zpl_statfs(struct dentry *dentry, struct kstatfs *statp)
132 error = -zfs_statvfs(dentry, statp);
133 ASSERT3S(error, <=, 0);
139 zpl_remount_fs(struct super_block *sb, int *flags, char *data)
142 error = -zfs_remount(sb, flags, data);
143 ASSERT3S(error, <=, 0);
149 zpl_umount_begin(struct super_block *sb)
151 zfs_sb_t *zsb = sb->s_fs_info;
155 * Best effort to unmount snapshots in .zfs/snapshot/. Normally this
156 * isn't required because snapshots have the MNT_SHRINKABLE flag set.
159 (void) zfsctl_unmount_snapshots(zsb, MNT_FORCE, &count);
163 * The Linux VFS automatically handles the following flags:
164 * MNT_NOSUID, MNT_NODEV, MNT_NOEXEC, MNT_NOATIME, MNT_READONLY
166 #ifdef HAVE_SHOW_OPTIONS_WITH_DENTRY
168 zpl_show_options(struct seq_file *seq, struct dentry *root)
170 zfs_sb_t *zsb = root->d_sb->s_fs_info;
172 seq_printf(seq, ",%s", zsb->z_flags & ZSB_XATTR ? "xattr" : "noxattr");
178 zpl_show_options(struct seq_file *seq, struct vfsmount *vfsp)
180 zfs_sb_t *zsb = vfsp->mnt_sb->s_fs_info;
182 seq_printf(seq, ",%s", zsb->z_flags & ZSB_XATTR ? "xattr" : "noxattr");
186 #endif /* HAVE_SHOW_OPTIONS_WITH_DENTRY */
189 zpl_fill_super(struct super_block *sb, void *data, int silent)
193 error = -zfs_domount(sb, data, silent);
194 ASSERT3S(error, <=, 0);
199 #ifdef HAVE_MOUNT_NODEV
200 static struct dentry *
201 zpl_mount(struct file_system_type *fs_type, int flags,
202 const char *osname, void *data)
204 zpl_mount_data_t zmd = { osname, data };
206 return mount_nodev(fs_type, flags, &zmd, zpl_fill_super);
210 zpl_get_sb(struct file_system_type *fs_type, int flags,
211 const char *osname, void *data, struct vfsmount *mnt)
213 zpl_mount_data_t zmd = { osname, data };
215 return get_sb_nodev(fs_type, flags, &zmd, zpl_fill_super, mnt);
217 #endif /* HAVE_MOUNT_NODEV */
220 zpl_kill_sb(struct super_block *sb)
228 * Linux 3.1 - 3.x API
230 * The Linux 3.1 API introduced per-sb cache shrinkers to replace the
231 * global ones. This allows us a mechanism to cleanly target a specific
232 * zfs file system when the dnode and inode caches grow too large.
234 * In addition, the 3.0 kernel added the iterate_supers_type() helper
235 * function which is used to safely walk all of the zfs file systems.
238 zpl_prune_sb(struct super_block *sb, void *arg)
243 error = -zfs_sb_prune(sb, *(unsigned long *)arg, &objects);
244 ASSERT3S(error, <=, 0);
250 zpl_prune_sbs(int64_t bytes_to_scan, void *private)
252 unsigned long nr_to_scan = (bytes_to_scan / sizeof(znode_t));
254 iterate_supers_type(&zpl_fs_type, zpl_prune_sb, &nr_to_scan);
259 * Linux 2.6.x - 3.0 API
261 * These are best effort interfaces are provided by the SPL to induce
262 * the Linux VM subsystem to reclaim a fraction of the both dnode and
263 * inode caches. Ideally, we want to just target the zfs file systems
264 * however our only option is to reclaim from them all.
267 zpl_prune_sbs(int64_t bytes_to_scan, void *private)
269 unsigned long nr_to_scan = (bytes_to_scan / sizeof(znode_t));
271 shrink_dcache_memory(nr_to_scan, GFP_KERNEL);
272 shrink_icache_memory(nr_to_scan, GFP_KERNEL);
275 #endif /* HAVE_SHRINK */
277 #ifdef HAVE_NR_CACHED_OBJECTS
279 zpl_nr_cached_objects(struct super_block *sb)
281 zfs_sb_t *zsb = sb->s_fs_info;
284 mutex_enter(&zsb->z_znodes_lock);
285 nr = zsb->z_nr_znodes;
286 mutex_exit(&zsb->z_znodes_lock);
290 #endif /* HAVE_NR_CACHED_OBJECTS */
292 #ifdef HAVE_FREE_CACHED_OBJECTS
294 * Attempt to evict some meta data from the cache. The ARC operates in
295 * terms of bytes while the Linux VFS uses objects. Now because this is
296 * just a best effort eviction and the exact values aren't critical so we
297 * extrapolate from an object count to a byte size using the znode_t size.
300 zpl_free_cached_objects(struct super_block *sb, int nr_to_scan)
302 arc_adjust_meta(nr_to_scan * sizeof(znode_t), B_FALSE);
304 #endif /* HAVE_FREE_CACHED_OBJECTS */
306 const struct super_operations zpl_super_operations = {
307 .alloc_inode = zpl_inode_alloc,
308 .destroy_inode = zpl_inode_destroy,
312 #ifdef HAVE_EVICT_INODE
313 .evict_inode = zpl_evict_inode,
315 .clear_inode = zpl_clear_inode,
316 .delete_inode = zpl_inode_delete,
317 #endif /* HAVE_EVICT_INODE */
318 .put_super = zpl_put_super,
319 .sync_fs = zpl_sync_fs,
320 .statfs = zpl_statfs,
321 .remount_fs = zpl_remount_fs,
322 .umount_begin = zpl_umount_begin,
323 .show_options = zpl_show_options,
325 #ifdef HAVE_NR_CACHED_OBJECTS
326 .nr_cached_objects = zpl_nr_cached_objects,
327 #endif /* HAVE_NR_CACHED_OBJECTS */
328 #ifdef HAVE_FREE_CACHED_OBJECTS
329 .free_cached_objects = zpl_free_cached_objects,
330 #endif /* HAVE_FREE_CACHED_OBJECTS */
333 struct file_system_type zpl_fs_type = {
334 .owner = THIS_MODULE,
336 #ifdef HAVE_MOUNT_NODEV
339 .get_sb = zpl_get_sb,
340 #endif /* HAVE_MOUNT_NODEV */
341 .kill_sb = zpl_kill_sb,