1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
2 * vim:expandtab:shiftwidth=8:tabstop=8:
5 * Lustre filesystem abstraction routines
7 * Copyright (C) 2004 Cluster File Systems, Inc.
9 * This file is part of Lustre, http://www.lustre.org.
11 * Lustre is free software; you can redistribute it and/or
12 * modify it under the terms of version 2 of the GNU General Public
13 * License as published by the Free Software Foundation.
15 * Lustre is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
20 * You should have received a copy of the GNU General Public License
21 * along with Lustre; if not, write to the Free Software
22 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
25 #define DEBUG_SUBSYSTEM S_SM
27 #include <linux/kmod.h>
28 #include <linux/init.h>
30 #include <linux/slab.h>
31 #include <linux/string.h>
32 #include <linux/obd_class.h>
33 #include <linux/obd_support.h>
34 #include <linux/lustre_lib.h>
35 #include <linux/lustre_idl.h>
36 #include <linux/lustre_fsfilt.h>
37 #include <linux/lustre_smfs.h>
38 #include "smfs_internal.h"
40 static void smfs_init_inode_info(struct inode *inode, void *opaque)
43 struct inode *cache_inode = NULL;
44 struct smfs_iget_args *sargs;
47 sargs = (struct smfs_iget_args *)opaque;
49 /* getting backing fs inode. */
50 ino = sargs ? sargs->s_ino : inode->i_ino;
51 cache_inode = iget(S2CSB(inode->i_sb), ino);
53 OBD_ALLOC(inode->u.generic_ip,
54 sizeof(struct smfs_inode_info));
56 LASSERT(inode->u.generic_ip);
57 I2CI(inode) = cache_inode;
59 CDEBUG(D_INODE, "cache_inode i_count ino %lu i_count %d\n",
60 cache_inode->i_ino, atomic_read(&cache_inode->i_count));
62 post_smfs_inode(inode, cache_inode);
63 sm_set_inode_ops(cache_inode, inode);
66 struct inode *dir = sargs->s_inode;
68 I2SMI(inode)->smi_flags = I2SMI(dir)->smi_flags;
73 static void smfs_clear_inode_info(struct inode *inode)
76 struct inode *cache_inode = I2CI(inode);
78 LASSERTF(((atomic_read(&cache_inode->i_count) == 1) ||
79 cache_inode == cache_inode->i_sb->s_root->d_inode),
80 "inode %p cache inode %p %lu i_count %d != 0 \n",
81 inode, cache_inode, cache_inode->i_ino,
82 atomic_read(&cache_inode->i_count));
84 if (cache_inode != cache_inode->i_sb->s_root->d_inode)
87 OBD_FREE(inode->u.generic_ip,
88 sizeof(struct smfs_inode_info));
89 inode->u.generic_ip = NULL;
93 static void smfs_read_inode2(struct inode *inode, void *opaque)
102 CDEBUG(D_INODE, "read_inode ino %lu\n", inode->i_ino);
103 smfs_init_inode_info(inode, opaque);
104 CDEBUG(D_INODE, "read_inode ino %lu icount %d \n",
105 inode->i_ino, atomic_read(&inode->i_count));
109 #if (LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0))
110 static int smfs_test_inode(struct inode *inode, unsigned long ino,
113 static int smfs_test_inode(struct inode *inode, void *opaque)
116 struct smfs_iget_args *sargs = (struct smfs_iget_args*)opaque;
123 if (inode->i_ino != sargs->s_ino)
127 if (SMFS_DO_COW(S2SMI(inode->i_sb)) &&
128 !smfs_snap_test_inode(inode, opaque))
132 struct inode *cache_inode = I2CI(inode);
134 /* this is needed to make symatry between smfs_put_inode(). */
135 LASSERT(cache_inode != NULL);
138 LASSERTF(cache_inode->i_ino == inode->i_ino,
139 "inode ino %lu != cache ino %lu",
140 cache_inode->i_ino, inode->i_ino);
142 smfs_init_inode_info(inode, opaque);
148 #if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,5,0))
149 int smfs_set_inode(struct inode *inode, void *opaque)
151 smfs_read_inode2(inode, opaque);
155 struct inode *smfs_iget(struct super_block *sb, ino_t hash,
156 struct smfs_iget_args *sargs)
161 inode = iget5_locked(sb, hash, smfs_test_inode,
162 smfs_set_inode, sargs);
164 if (inode->i_state & I_NEW)
165 unlock_new_inode(inode);
166 CDEBUG(D_VFSTRACE, "inode: %lu/%u(%p) index %d "
167 "ino %d\n", inode->i_ino, inode->i_generation,
168 inode, sargs->s_index, sargs->s_ino);
174 struct inode *smfs_iget(struct super_block *sb, ino_t hash,
175 struct smfs_iget_args *sargs)
180 inode = iget4(sb, hash, smfs_test_inode, sargs);
182 struct inode *cache_inode = I2CI(inode);
183 LASSERTF((inode->i_ino == cache_inode->i_ino),
184 "inode %p ino %lu != cache inode %p ino %lu",
185 inode, inode->i_ino, cache_inode, cache_inode->i_ino);
186 CDEBUG(D_VFSTRACE, "inode: %lu/%u(%p)\n", inode->i_ino,
187 inode->i_generation, inode);
193 struct inode *smfs_get_inode(struct super_block *sb, ino_t hash,
194 struct inode *dir, int index)
196 struct smfs_iget_args sargs;
202 sargs.s_index = index;
203 inode = smfs_iget(sb, hash, &sargs);
208 static void smfs_delete_inode(struct inode *inode)
215 static void smfs_write_inode(struct inode *inode, int wait)
217 struct inode *cache_inode;
220 cache_inode = I2CI(inode);
221 LASSERT(cache_inode != NULL);
223 pre_smfs_inode(inode, cache_inode);
224 if (S2CSB(inode->i_sb)->s_op->write_inode)
225 S2CSB(inode->i_sb)->s_op->write_inode(cache_inode, wait);
227 post_smfs_inode(inode, cache_inode);
231 static void smfs_dirty_inode(struct inode *inode)
233 struct inode *cache_inode;
236 cache_inode = I2CI(inode);
237 if (!cache_inode || !S2CSB(inode->i_sb)) {
242 pre_smfs_inode(inode, cache_inode);
243 if (S2CSB(inode->i_sb)->s_op->dirty_inode)
244 S2CSB(inode->i_sb)->s_op->dirty_inode(cache_inode);
246 post_smfs_inode(inode, cache_inode);
250 static void smfs_put_inode(struct inode *inode)
252 struct inode *cache_inode;
255 cache_inode = I2CI(inode);
256 LASSERT(cache_inode != NULL);
258 if (atomic_read(&cache_inode->i_count) > 1)
262 * check if we have to release backend inode. As iput() calls fs
263 * specific ->put_inode() first and than decrements inode rerfcount, we
264 * should check here ->i_count for 1, not for 0.
266 * In principle we could rely on ->clear_inode(), but it will be called
267 * later, and thus we will have iputing of @inode and @cache_inode in
268 * different control paths, this is why we do it here. --umka
270 if (atomic_read(&inode->i_count) == 1 &&
271 cache_inode->i_sb->s_root->d_inode != cache_inode)
272 smfs_clear_inode_info(inode);
277 static void smfs_clear_inode(struct inode *inode)
280 smfs_clear_inode_info(inode);
284 static void smfs_write_super(struct super_block *sb)
293 if (S2CSB(sb)->s_op->write_super)
294 S2CSB(sb)->s_op->write_super(S2CSB(sb));
295 duplicate_sb(sb, S2CSB(sb));
299 static void smfs_write_super_lockfs(struct super_block *sb)
301 struct super_block *cache_sb;
304 cache_sb = S2CSB(sb);
310 if (cache_sb->s_op->write_super_lockfs)
311 cache_sb->s_op->write_super_lockfs(cache_sb);
313 duplicate_sb(sb, cache_sb);
317 static void smfs_unlockfs(struct super_block *sb)
319 struct super_block *cache_sb;
322 cache_sb = S2CSB(sb);
328 if (cache_sb->s_op->unlockfs)
329 cache_sb->s_op->unlockfs(cache_sb);
331 duplicate_sb(sb, cache_sb);
335 #if (LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0))
336 static int smfs_statfs(struct super_block *sb, struct statfs *buf)
338 static int smfs_statfs(struct super_block *sb, struct kstatfs *buf)
341 struct super_block *cache_sb;
345 cache_sb = S2CSB(sb);
349 if (cache_sb->s_op->statfs)
350 rc = cache_sb->s_op->statfs(cache_sb, buf);
352 duplicate_sb(sb, cache_sb);
355 static int smfs_remount(struct super_block *sb, int *flags, char *data)
357 struct super_block *cache_sb;
361 cache_sb = S2CSB(sb);
366 if (cache_sb->s_op->remount_fs)
367 rc = cache_sb->s_op->remount_fs(cache_sb, flags, data);
369 duplicate_sb(sb, cache_sb);
373 struct super_operations smfs_super_ops = {
374 #if (LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0))
375 .read_inode2 = smfs_read_inode2,
377 .clear_inode = smfs_clear_inode,
378 .put_super = smfs_put_super,
379 .delete_inode = smfs_delete_inode,
380 .write_inode = smfs_write_inode,
381 .dirty_inode = smfs_dirty_inode, /* BKL not held. */
382 .put_inode = smfs_put_inode, /* BKL not held. */
383 .write_super = smfs_write_super, /* BKL held */
384 .write_super_lockfs = smfs_write_super_lockfs, /* BKL not held. */
385 .unlockfs = smfs_unlockfs, /* BKL not held. */
386 .statfs = smfs_statfs, /* BKL held */
387 .remount_fs = smfs_remount, /* BKL held */
390 int is_smfs_sb(struct super_block *sb)
392 return (sb->s_op->put_super == smfs_super_ops.put_super);
394 EXPORT_SYMBOL(is_smfs_sb);