2 * Copyright (C) 2005-2012 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
26 * they are necessary regardless sysfs is disabled.
28 void au_si_free(struct kobject *kobj)
30 struct au_sbinfo *sbinfo;
31 char *locked __maybe_unused; /* debug only */
33 sbinfo = container_of(kobj, struct au_sbinfo, si_kobj);
34 AuDebugOn(!list_empty(&sbinfo->si_plink.head));
35 AuDebugOn(atomic_read(&sbinfo->si_nowait.nw_len));
37 au_rw_write_lock(&sbinfo->si_rwsem);
39 au_rw_write_unlock(&sbinfo->si_rwsem);
41 AuDebugOn(radix_tree_gang_lookup
42 (&sbinfo->au_si_pid.tree, (void **)&locked,
43 /*first_index*/PID_MAX_DEFAULT - 1,
44 /*max_items*/sizeof(locked)/sizeof(*locked)));
46 kfree(sbinfo->si_branch);
47 kfree(sbinfo->au_si_pid.bitmap);
48 mutex_destroy(&sbinfo->si_xib_mtx);
49 AuRwDestroy(&sbinfo->si_rwsem);
54 int au_si_alloc(struct super_block *sb)
57 struct au_sbinfo *sbinfo;
58 static struct lock_class_key aufs_si;
61 sbinfo = kzalloc(sizeof(*sbinfo), GFP_NOFS);
62 if (unlikely(!sbinfo))
65 BUILD_BUG_ON(sizeof(unsigned long) !=
66 sizeof(*sbinfo->au_si_pid.bitmap));
67 sbinfo->au_si_pid.bitmap = kcalloc(BITS_TO_LONGS(PID_MAX_DEFAULT),
68 sizeof(*sbinfo->au_si_pid.bitmap),
70 if (unlikely(!sbinfo->au_si_pid.bitmap))
73 /* will be reallocated separately */
74 sbinfo->si_branch = kzalloc(sizeof(*sbinfo->si_branch), GFP_NOFS);
75 if (unlikely(!sbinfo->si_branch))
78 err = sysaufs_si_init(sbinfo);
82 au_nwt_init(&sbinfo->si_nowait);
83 au_rw_init_wlock(&sbinfo->si_rwsem);
84 au_rw_class(&sbinfo->si_rwsem, &aufs_si);
85 spin_lock_init(&sbinfo->au_si_pid.tree_lock);
86 INIT_RADIX_TREE(&sbinfo->au_si_pid.tree, GFP_ATOMIC | __GFP_NOFAIL);
88 atomic_long_set(&sbinfo->si_ninodes, 0);
89 atomic_long_set(&sbinfo->si_nfiles, 0);
93 sbinfo->si_wbr_copyup = AuWbrCopyup_Def;
94 sbinfo->si_wbr_create = AuWbrCreate_Def;
95 sbinfo->si_wbr_copyup_ops = au_wbr_copyup_ops + sbinfo->si_wbr_copyup;
96 sbinfo->si_wbr_create_ops = au_wbr_create_ops + sbinfo->si_wbr_create;
98 sbinfo->si_mntflags = au_opts_plink(AuOpt_Def);
100 mutex_init(&sbinfo->si_xib_mtx);
101 sbinfo->si_xino_brid = -1;
102 /* leave si_xib_last_pindex and si_xib_next_bit */
104 sbinfo->si_rdcache = msecs_to_jiffies(AUFS_RDCACHE_DEF * MSEC_PER_SEC);
105 sbinfo->si_rdblk = AUFS_RDBLK_DEF;
106 sbinfo->si_rdhash = AUFS_RDHASH_DEF;
107 sbinfo->si_dirwh = AUFS_DIRWH_DEF;
109 au_spl_init(&sbinfo->si_plink);
110 init_waitqueue_head(&sbinfo->si_plink_wq);
111 spin_lock_init(&sbinfo->si_plink_maint_lock);
113 /* leave other members for sysaufs and si_mnt. */
115 sb->s_fs_info = sbinfo;
117 au_debug_sbinfo_init(sbinfo);
118 return 0; /* success */
121 kfree(sbinfo->si_branch);
123 kfree(sbinfo->au_si_pid.bitmap);
130 int au_sbr_realloc(struct au_sbinfo *sbinfo, int nbr)
133 struct au_branch **brp;
135 AuRwMustWriteLock(&sbinfo->si_rwsem);
138 sz = sizeof(*brp) * (sbinfo->si_bend + 1);
141 brp = au_kzrealloc(sbinfo->si_branch, sz, sizeof(*brp) * nbr, GFP_NOFS);
143 sbinfo->si_branch = brp;
150 /* ---------------------------------------------------------------------- */
152 unsigned int au_sigen_inc(struct super_block *sb)
158 gen = ++au_sbi(sb)->si_generation;
159 au_update_digen(sb->s_root);
160 au_update_iigen(sb->s_root->d_inode);
161 sb->s_root->d_inode->i_version++;
165 aufs_bindex_t au_new_br_id(struct super_block *sb)
169 struct au_sbinfo *sbinfo;
174 for (i = 0; i <= AUFS_BRANCH_MAX; i++) {
175 br_id = ++sbinfo->si_last_br_id;
176 AuDebugOn(br_id < 0);
177 if (br_id && au_br_index(sb, br_id) < 0)
184 /* ---------------------------------------------------------------------- */
186 /* it is ok that new 'nwt' tasks are appended while we are sleeping */
187 int si_read_lock(struct super_block *sb, int flags)
192 if (au_ftest_lock(flags, FLUSH))
193 au_nwt_flush(&au_sbi(sb)->si_nowait);
195 si_noflush_read_lock(sb);
196 err = au_plink_maint(sb, flags);
203 int si_write_lock(struct super_block *sb, int flags)
207 if (au_ftest_lock(flags, FLUSH))
208 au_nwt_flush(&au_sbi(sb)->si_nowait);
210 si_noflush_write_lock(sb);
211 err = au_plink_maint(sb, flags);
218 /* dentry and super_block lock. call at entry point */
219 int aufs_read_lock(struct dentry *dentry, int flags)
222 struct super_block *sb;
225 err = si_read_lock(sb, flags);
229 if (au_ftest_lock(flags, DW))
230 di_write_lock_child(dentry);
232 di_read_lock_child(dentry, flags);
234 if (au_ftest_lock(flags, GEN)) {
235 err = au_digen_test(dentry, au_sigen(sb));
236 AuDebugOn(!err && au_dbrange_test(dentry));
238 aufs_read_unlock(dentry, flags);
245 void aufs_read_unlock(struct dentry *dentry, int flags)
247 if (au_ftest_lock(flags, DW))
248 di_write_unlock(dentry);
250 di_read_unlock(dentry, flags);
251 si_read_unlock(dentry->d_sb);
254 void aufs_write_lock(struct dentry *dentry)
256 si_write_lock(dentry->d_sb, AuLock_FLUSH | AuLock_NOPLMW);
257 di_write_lock_child(dentry);
260 void aufs_write_unlock(struct dentry *dentry)
262 di_write_unlock(dentry);
263 si_write_unlock(dentry->d_sb);
266 int aufs_read_and_write_lock2(struct dentry *d1, struct dentry *d2, int flags)
270 struct super_block *sb;
273 err = si_read_lock(sb, flags);
277 di_write_lock2_child(d1, d2, au_ftest_lock(flags, DIR));
279 if (au_ftest_lock(flags, GEN)) {
280 sigen = au_sigen(sb);
281 err = au_digen_test(d1, sigen);
282 AuDebugOn(!err && au_dbrange_test(d1));
284 err = au_digen_test(d2, sigen);
285 AuDebugOn(!err && au_dbrange_test(d2));
288 aufs_read_and_write_unlock2(d1, d2);
295 void aufs_read_and_write_unlock2(struct dentry *d1, struct dentry *d2)
297 di_write_unlock2(d1, d2);
298 si_read_unlock(d1->d_sb);
301 /* ---------------------------------------------------------------------- */
303 int si_pid_test_slow(struct super_block *sb)
308 p = radix_tree_lookup(&au_sbi(sb)->au_si_pid.tree, current->pid);
314 void si_pid_set_slow(struct super_block *sb)
317 struct au_sbinfo *sbinfo;
319 AuDebugOn(si_pid_test_slow(sb));
322 err = radix_tree_preload(GFP_NOFS | __GFP_NOFAIL);
324 spin_lock(&sbinfo->au_si_pid.tree_lock);
325 err = radix_tree_insert(&sbinfo->au_si_pid.tree, current->pid,
326 /*any valid ptr*/sb);
327 spin_unlock(&sbinfo->au_si_pid.tree_lock);
329 radix_tree_preload_end();
332 void si_pid_clr_slow(struct super_block *sb)
335 struct au_sbinfo *sbinfo;
337 AuDebugOn(!si_pid_test_slow(sb));
340 spin_lock(&sbinfo->au_si_pid.tree_lock);
341 p = radix_tree_delete(&sbinfo->au_si_pid.tree, current->pid);
342 spin_unlock(&sbinfo->au_si_pid.tree_lock);