2 * Copyright (C) 2005-2010 Junjiro R. Okajima
4 * This program, aufs is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
20 * superblock private data
23 #include <linux/jiffies.h>
27 * they are necessary regardless sysfs is disabled.
29 void au_si_free(struct kobject *kobj)
31 struct au_sbinfo *sbinfo;
32 char *locked __maybe_unused; /* debug only */
34 sbinfo = container_of(kobj, struct au_sbinfo, si_kobj);
35 AuDebugOn(!list_empty(&sbinfo->si_plink.head));
36 AuDebugOn(atomic_read(&sbinfo->si_nowait.nw_len));
38 au_rw_write_lock(&sbinfo->si_rwsem);
40 au_rw_write_unlock(&sbinfo->si_rwsem);
42 AuDebugOn(radix_tree_gang_lookup
43 (&sbinfo->au_si_pid.tree, (void **)&locked,
44 /*first_index*/PID_MAX_DEFAULT - 1,
45 /*max_items*/sizeof(locked)/sizeof(*locked)));
47 kfree(sbinfo->si_branch);
48 kfree(sbinfo->au_si_pid.bitmap);
49 mutex_destroy(&sbinfo->si_xib_mtx);
50 AuRwDestroy(&sbinfo->si_rwsem);
55 int au_si_alloc(struct super_block *sb)
58 struct au_sbinfo *sbinfo;
59 static struct lock_class_key aufs_si;
62 sbinfo = kzalloc(sizeof(*sbinfo), GFP_NOFS);
63 if (unlikely(!sbinfo))
66 BUILD_BUG_ON(sizeof(unsigned long) !=
67 sizeof(*sbinfo->au_si_pid.bitmap));
68 sbinfo->au_si_pid.bitmap = kcalloc(BITS_TO_LONGS(PID_MAX_DEFAULT),
69 sizeof(*sbinfo->au_si_pid.bitmap),
71 if (unlikely(!sbinfo->au_si_pid.bitmap))
74 /* will be reallocated separately */
75 sbinfo->si_branch = kzalloc(sizeof(*sbinfo->si_branch), GFP_NOFS);
76 if (unlikely(!sbinfo->si_branch))
79 err = sysaufs_si_init(sbinfo);
83 au_nwt_init(&sbinfo->si_nowait);
84 au_rw_init_wlock(&sbinfo->si_rwsem);
85 au_rw_class(&sbinfo->si_rwsem, &aufs_si);
86 spin_lock_init(&sbinfo->au_si_pid.tree_lock);
87 INIT_RADIX_TREE(&sbinfo->au_si_pid.tree, GFP_ATOMIC | __GFP_NOFAIL);
89 atomic_long_set(&sbinfo->si_ninodes, 0);
91 atomic_long_set(&sbinfo->si_nfiles, 0);
95 sbinfo->si_wbr_copyup = AuWbrCopyup_Def;
96 sbinfo->si_wbr_create = AuWbrCreate_Def;
97 sbinfo->si_wbr_copyup_ops = au_wbr_copyup_ops + sbinfo->si_wbr_copyup;
98 sbinfo->si_wbr_create_ops = au_wbr_create_ops + sbinfo->si_wbr_create;
100 sbinfo->si_mntflags = au_opts_plink(AuOpt_Def);
102 mutex_init(&sbinfo->si_xib_mtx);
103 sbinfo->si_xino_brid = -1;
104 /* leave si_xib_last_pindex and si_xib_next_bit */
106 sbinfo->si_rdcache = msecs_to_jiffies(AUFS_RDCACHE_DEF * MSEC_PER_SEC);
107 sbinfo->si_rdblk = AUFS_RDBLK_DEF;
108 sbinfo->si_rdhash = AUFS_RDHASH_DEF;
109 sbinfo->si_dirwh = AUFS_DIRWH_DEF;
111 au_spl_init(&sbinfo->si_plink);
112 init_waitqueue_head(&sbinfo->si_plink_wq);
113 spin_lock_init(&sbinfo->si_plink_maint_lock);
115 /* leave other members for sysaufs and si_mnt. */
117 sb->s_fs_info = sbinfo;
119 au_debug_sbinfo_init(sbinfo);
120 return 0; /* success */
123 kfree(sbinfo->si_branch);
125 kfree(sbinfo->au_si_pid.bitmap);
132 int au_sbr_realloc(struct au_sbinfo *sbinfo, int nbr)
135 struct au_branch **brp;
137 AuRwMustWriteLock(&sbinfo->si_rwsem);
140 sz = sizeof(*brp) * (sbinfo->si_bend + 1);
143 brp = au_kzrealloc(sbinfo->si_branch, sz, sizeof(*brp) * nbr, GFP_NOFS);
145 sbinfo->si_branch = brp;
152 /* ---------------------------------------------------------------------- */
154 unsigned int au_sigen_inc(struct super_block *sb)
160 gen = ++au_sbi(sb)->si_generation;
161 au_update_digen(sb->s_root);
162 au_update_iigen(sb->s_root->d_inode);
163 sb->s_root->d_inode->i_version++;
167 aufs_bindex_t au_new_br_id(struct super_block *sb)
171 struct au_sbinfo *sbinfo;
176 for (i = 0; i <= AUFS_BRANCH_MAX; i++) {
177 br_id = ++sbinfo->si_last_br_id;
178 AuDebugOn(br_id < 0);
179 if (br_id && au_br_index(sb, br_id) < 0)
186 /* ---------------------------------------------------------------------- */
188 /* it is ok that new 'nwt' tasks are appended while we are sleeping */
189 int si_read_lock(struct super_block *sb, int flags)
194 if (au_ftest_lock(flags, FLUSH))
195 au_nwt_flush(&au_sbi(sb)->si_nowait);
197 si_noflush_read_lock(sb);
198 err = au_plink_maint(sb, flags);
205 int si_write_lock(struct super_block *sb, int flags)
209 if (au_ftest_lock(flags, FLUSH))
210 au_nwt_flush(&au_sbi(sb)->si_nowait);
212 si_noflush_write_lock(sb);
213 err = au_plink_maint(sb, flags);
220 /* dentry and super_block lock. call at entry point */
221 int aufs_read_lock(struct dentry *dentry, int flags)
225 err = si_read_lock(dentry->d_sb, flags);
227 if (au_ftest_lock(flags, DW))
228 di_write_lock_child(dentry);
230 di_read_lock_child(dentry, flags);
236 void aufs_read_unlock(struct dentry *dentry, int flags)
238 if (au_ftest_lock(flags, DW))
239 di_write_unlock(dentry);
241 di_read_unlock(dentry, flags);
242 si_read_unlock(dentry->d_sb);
245 void aufs_write_lock(struct dentry *dentry)
247 si_write_lock(dentry->d_sb, AuLock_FLUSH | AuLock_NOPLMW);
248 di_write_lock_child(dentry);
251 void aufs_write_unlock(struct dentry *dentry)
253 di_write_unlock(dentry);
254 si_write_unlock(dentry->d_sb);
257 int aufs_read_and_write_lock2(struct dentry *d1, struct dentry *d2, int flags)
261 err = si_read_lock(d1->d_sb, flags);
263 di_write_lock2_child(d1, d2, au_ftest_lock(flags, DIR));
267 void aufs_read_and_write_unlock2(struct dentry *d1, struct dentry *d2)
269 di_write_unlock2(d1, d2);
270 si_read_unlock(d1->d_sb);
273 /* ---------------------------------------------------------------------- */
275 int si_pid_test_slow(struct super_block *sb)
280 p = radix_tree_lookup(&au_sbi(sb)->au_si_pid.tree, current->pid);
286 void si_pid_set_slow(struct super_block *sb)
289 struct au_sbinfo *sbinfo;
291 AuDebugOn(si_pid_test_slow(sb));
294 err = radix_tree_preload(GFP_NOFS | __GFP_NOFAIL);
296 spin_lock(&sbinfo->au_si_pid.tree_lock);
297 err = radix_tree_insert(&sbinfo->au_si_pid.tree, current->pid,
299 spin_unlock(&sbinfo->au_si_pid.tree_lock);
301 radix_tree_preload_end();
304 void si_pid_clr_slow(struct super_block *sb)
307 struct au_sbinfo *sbinfo;
309 AuDebugOn(!si_pid_test_slow(sb));
312 spin_lock(&sbinfo->au_si_pid.tree_lock);
313 p = radix_tree_delete(&sbinfo->au_si_pid.tree, current->pid);
314 spin_unlock(&sbinfo->au_si_pid.tree_lock);
315 AuDebugOn(1 != (long)p);