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>
33 zpl_inode_alloc(struct super_block *sb)
37 VERIFY3S(zfs_inode_alloc(sb, &ip), ==, 0);
44 zpl_inode_destroy(struct inode *ip)
46 ASSERT(atomic_read(&ip->i_count) == 0);
47 zfs_inode_destroy(ip);
51 * When ->drop_inode() is called its return value indicates if the
52 * inode should be evicted from the inode cache. If the inode is
53 * unhashed and has no links the default policy is to evict it
56 * Prior to 2.6.36 this eviction was accomplished by the vfs calling
57 * ->delete_inode(). It was ->delete_inode()'s responsibility to
58 * truncate the inode pages and call clear_inode(). The call to
59 * clear_inode() synchronously invalidates all the buffers and
60 * calls ->clear_inode(). It was ->clear_inode()'s responsibility
61 * to cleanup and filesystem specific data before freeing the inode.
63 * This elaborate mechanism was replaced by ->evict_inode() which
64 * does the job of both ->delete_inode() and ->clear_inode(). It
65 * will be called exactly once, and when it returns the inode must
66 * be in a state where it can simply be freed. The ->evict_inode()
67 * callback must minimally truncate the inode pages, and call
68 * end_writeback() to complete all outstanding writeback for the
69 * inode. After this is complete evict inode can cleanup any
70 * remaining filesystem specific data.
72 #ifdef HAVE_EVICT_INODE
74 zpl_evict_inode(struct inode *ip)
76 truncate_setsize(ip, 0);
84 zpl_clear_inode(struct inode *ip)
90 zpl_inode_delete(struct inode *ip)
92 truncate_setsize(ip, 0);
96 #endif /* HAVE_EVICT_INODE */
99 zpl_put_super(struct super_block *sb)
103 error = -zfs_umount(sb);
104 ASSERT3S(error, <=, 0);
108 zpl_sync_fs(struct super_block *sb, int wait)
114 error = -zfs_sync(sb, wait, cr);
116 ASSERT3S(error, <=, 0);
122 zpl_statfs(struct dentry *dentry, struct kstatfs *statp)
126 error = -zfs_statvfs(dentry, statp);
127 ASSERT3S(error, <=, 0);
133 zpl_remount_fs(struct super_block *sb, int *flags, char *data)
136 error = -zfs_remount(sb, flags, data);
137 ASSERT3S(error, <=, 0);
143 * The Linux VFS automatically handles the following flags:
144 * MNT_NOSUID, MNT_NODEV, MNT_NOEXEC, MNT_NOATIME, MNT_READONLY
146 #ifdef HAVE_SHOW_OPTIONS_WITH_DENTRY
148 zpl_show_options(struct seq_file *seq, struct dentry *root)
150 zfs_sb_t *zsb = root->d_sb->s_fs_info;
152 seq_printf(seq, ",%s", zsb->z_flags & ZSB_XATTR ? "xattr" : "noxattr");
158 zpl_show_options(struct seq_file *seq, struct vfsmount *vfsp)
160 zfs_sb_t *zsb = vfsp->mnt_sb->s_fs_info;
162 seq_printf(seq, ",%s", zsb->z_flags & ZSB_XATTR ? "xattr" : "noxattr");
166 #endif /* HAVE_SHOW_OPTIONS_WITH_DENTRY */
169 zpl_fill_super(struct super_block *sb, void *data, int silent)
173 error = -zfs_domount(sb, data, silent);
174 ASSERT3S(error, <=, 0);
179 #ifdef HAVE_MOUNT_NODEV
180 static struct dentry *
181 zpl_mount(struct file_system_type *fs_type, int flags,
182 const char *osname, void *data)
184 zpl_mount_data_t zmd = { osname, data };
186 return mount_nodev(fs_type, flags, &zmd, zpl_fill_super);
190 zpl_get_sb(struct file_system_type *fs_type, int flags,
191 const char *osname, void *data, struct vfsmount *mnt)
193 zpl_mount_data_t zmd = { osname, data };
195 return get_sb_nodev(fs_type, flags, &zmd, zpl_fill_super, mnt);
197 #endif /* HAVE_MOUNT_NODEV */
200 zpl_kill_sb(struct super_block *sb)
203 zfs_sb_t *zsb = sb->s_fs_info;
205 if (zsb && dmu_objset_is_snapshot(zsb->z_os))
206 zfs_snap_destroy(zsb);
207 #endif /* HAVE_SNAPSHOT */
214 * Linux 3.1 - 3.x API
216 * The Linux 3.1 API introduced per-sb cache shrinkers to replace the
217 * global ones. This allows us a mechanism to cleanly target a specific
218 * zfs file system when the dnode and inode caches grow too large.
220 * In addition, the 3.0 kernel added the iterate_supers_type() helper
221 * function which is used to safely walk all of the zfs file systems.
224 zpl_prune_sb(struct super_block *sb, void *arg)
229 error = -zfs_sb_prune(sb, *(unsigned long *)arg, &objects);
230 ASSERT3S(error, <=, 0);
236 zpl_prune_sbs(int64_t bytes_to_scan, void *private)
238 unsigned long nr_to_scan = (bytes_to_scan / sizeof(znode_t));
240 iterate_supers_type(&zpl_fs_type, zpl_prune_sb, &nr_to_scan);
245 * Linux 2.6.x - 3.0 API
247 * These are best effort interfaces are provided by the SPL to induce
248 * the Linux VM subsystem to reclaim a fraction of the both dnode and
249 * inode caches. Ideally, we want to just target the zfs file systems
250 * however our only option is to reclaim from them all.
253 zpl_prune_sbs(int64_t bytes_to_scan, void *private)
255 unsigned long nr_to_scan = (bytes_to_scan / sizeof(znode_t));
257 shrink_dcache_memory(nr_to_scan, GFP_KERNEL);
258 shrink_icache_memory(nr_to_scan, GFP_KERNEL);
261 #endif /* HAVE_SHRINK */
263 #ifdef HAVE_NR_CACHED_OBJECTS
265 zpl_nr_cached_objects(struct super_block *sb)
267 zfs_sb_t *zsb = sb->s_fs_info;
270 mutex_enter(&zsb->z_znodes_lock);
271 nr = zsb->z_nr_znodes;
272 mutex_exit(&zsb->z_znodes_lock);
276 #endif /* HAVE_NR_CACHED_OBJECTS */
278 #ifdef HAVE_FREE_CACHED_OBJECTS
280 * Attempt to evict some meta data from the cache. The ARC operates in
281 * terms of bytes while the Linux VFS uses objects. Now because this is
282 * just a best effort eviction and the exact values aren't critical so we
283 * extrapolate from an object count to a byte size using the znode_t size.
286 zpl_free_cached_objects(struct super_block *sb, int nr_to_scan)
288 arc_adjust_meta(nr_to_scan * sizeof(znode_t), B_FALSE);
290 #endif /* HAVE_FREE_CACHED_OBJECTS */
292 const struct super_operations zpl_super_operations = {
293 .alloc_inode = zpl_inode_alloc,
294 .destroy_inode = zpl_inode_destroy,
298 #ifdef HAVE_EVICT_INODE
299 .evict_inode = zpl_evict_inode,
301 .clear_inode = zpl_clear_inode,
302 .delete_inode = zpl_inode_delete,
303 #endif /* HAVE_EVICT_INODE */
304 .put_super = zpl_put_super,
306 .sync_fs = zpl_sync_fs,
307 .statfs = zpl_statfs,
308 .remount_fs = zpl_remount_fs,
309 .show_options = zpl_show_options,
311 #ifdef HAVE_NR_CACHED_OBJECTS
312 .nr_cached_objects = zpl_nr_cached_objects,
313 #endif /* HAVE_NR_CACHED_OBJECTS */
314 #ifdef HAVE_FREE_CACHED_OBJECTS
315 .free_cached_objects = zpl_free_cached_objects,
316 #endif /* HAVE_FREE_CACHED_OBJECTS */
319 struct file_system_type zpl_fs_type = {
320 .owner = THIS_MODULE,
322 #ifdef HAVE_MOUNT_NODEV
325 .get_sb = zpl_get_sb,
326 #endif /* HAVE_MOUNT_NODEV */
327 .kill_sb = zpl_kill_sb,