2 * Copyright (C) 2005-2013 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)
31 struct au_sbinfo *sbinfo;
32 char *locked __maybe_unused; /* debug only */
34 sbinfo = container_of(kobj, struct au_sbinfo, si_kobj);
35 for (i = 0; i < AuPlink_NHASH; i++)
36 AuDebugOn(!hlist_empty(&sbinfo->si_plink[i].head));
37 AuDebugOn(atomic_read(&sbinfo->si_nowait.nw_len));
39 au_rw_write_lock(&sbinfo->si_rwsem);
41 au_rw_write_unlock(&sbinfo->si_rwsem);
43 AuDebugOn(radix_tree_gang_lookup
44 (&sbinfo->au_si_pid.tree, (void **)&locked,
45 /*first_index*/PID_MAX_DEFAULT - 1,
46 /*max_items*/sizeof(locked)/sizeof(*locked)));
48 kfree(sbinfo->si_branch);
49 kfree(sbinfo->au_si_pid.bitmap);
50 mutex_destroy(&sbinfo->si_xib_mtx);
51 AuRwDestroy(&sbinfo->si_rwsem);
56 int au_si_alloc(struct super_block *sb)
59 struct au_sbinfo *sbinfo;
60 static struct lock_class_key aufs_si;
63 sbinfo = kzalloc(sizeof(*sbinfo), GFP_NOFS);
64 if (unlikely(!sbinfo))
67 BUILD_BUG_ON(sizeof(unsigned long) !=
68 sizeof(*sbinfo->au_si_pid.bitmap));
69 sbinfo->au_si_pid.bitmap = kcalloc(BITS_TO_LONGS(PID_MAX_DEFAULT),
70 sizeof(*sbinfo->au_si_pid.bitmap),
72 if (unlikely(!sbinfo->au_si_pid.bitmap))
75 /* will be reallocated separately */
76 sbinfo->si_branch = kzalloc(sizeof(*sbinfo->si_branch), GFP_NOFS);
77 if (unlikely(!sbinfo->si_branch))
80 err = sysaufs_si_init(sbinfo);
84 au_nwt_init(&sbinfo->si_nowait);
85 au_rw_init_wlock(&sbinfo->si_rwsem);
86 au_rw_class(&sbinfo->si_rwsem, &aufs_si);
87 spin_lock_init(&sbinfo->au_si_pid.tree_lock);
88 INIT_RADIX_TREE(&sbinfo->au_si_pid.tree, GFP_ATOMIC | __GFP_NOFAIL);
90 atomic_long_set(&sbinfo->si_ninodes, 0);
91 atomic_long_set(&sbinfo->si_nfiles, 0);
94 sbinfo->si_last_br_id = AUFS_BRANCH_MAX / 2;
96 sbinfo->si_wbr_copyup = AuWbrCopyup_Def;
97 sbinfo->si_wbr_create = AuWbrCreate_Def;
98 sbinfo->si_wbr_copyup_ops = au_wbr_copyup_ops + sbinfo->si_wbr_copyup;
99 sbinfo->si_wbr_create_ops = au_wbr_create_ops + sbinfo->si_wbr_create;
101 sbinfo->si_mntflags = au_opts_plink(AuOpt_Def);
103 sbinfo->si_xino_jiffy = jiffies;
104 sbinfo->si_xino_expire
105 = msecs_to_jiffies(AUFS_XINO_DEF_SEC * MSEC_PER_SEC);
106 mutex_init(&sbinfo->si_xib_mtx);
107 sbinfo->si_xino_brid = -1;
108 /* leave si_xib_last_pindex and si_xib_next_bit */
110 sbinfo->si_rdcache = msecs_to_jiffies(AUFS_RDCACHE_DEF * MSEC_PER_SEC);
111 sbinfo->si_rdblk = AUFS_RDBLK_DEF;
112 sbinfo->si_rdhash = AUFS_RDHASH_DEF;
113 sbinfo->si_dirwh = AUFS_DIRWH_DEF;
115 for (i = 0; i < AuPlink_NHASH; i++)
116 au_sphl_init(sbinfo->si_plink + i);
117 init_waitqueue_head(&sbinfo->si_plink_wq);
118 spin_lock_init(&sbinfo->si_plink_maint_lock);
120 /* leave other members for sysaufs and si_mnt. */
122 sb->s_fs_info = sbinfo;
124 au_debug_sbinfo_init(sbinfo);
125 return 0; /* success */
128 kfree(sbinfo->si_branch);
130 kfree(sbinfo->au_si_pid.bitmap);
137 int au_sbr_realloc(struct au_sbinfo *sbinfo, int nbr)
140 struct au_branch **brp;
142 AuRwMustWriteLock(&sbinfo->si_rwsem);
145 sz = sizeof(*brp) * (sbinfo->si_bend + 1);
148 brp = au_kzrealloc(sbinfo->si_branch, sz, sizeof(*brp) * nbr, GFP_NOFS);
150 sbinfo->si_branch = brp;
157 /* ---------------------------------------------------------------------- */
159 unsigned int au_sigen_inc(struct super_block *sb)
165 gen = ++au_sbi(sb)->si_generation;
166 au_update_digen(sb->s_root);
167 au_update_iigen(sb->s_root->d_inode, /*half*/0);
168 sb->s_root->d_inode->i_version++;
172 aufs_bindex_t au_new_br_id(struct super_block *sb)
176 struct au_sbinfo *sbinfo;
181 for (i = 0; i <= AUFS_BRANCH_MAX; i++) {
182 br_id = ++sbinfo->si_last_br_id;
183 AuDebugOn(br_id < 0);
184 if (br_id && au_br_index(sb, br_id) < 0)
191 /* ---------------------------------------------------------------------- */
193 /* it is ok that new 'nwt' tasks are appended while we are sleeping */
194 int si_read_lock(struct super_block *sb, int flags)
199 if (au_ftest_lock(flags, FLUSH))
200 au_nwt_flush(&au_sbi(sb)->si_nowait);
202 si_noflush_read_lock(sb);
203 err = au_plink_maint(sb, flags);
210 int si_write_lock(struct super_block *sb, int flags)
214 if (au_ftest_lock(flags, FLUSH))
215 au_nwt_flush(&au_sbi(sb)->si_nowait);
217 si_noflush_write_lock(sb);
218 err = au_plink_maint(sb, flags);
225 /* dentry and super_block lock. call at entry point */
226 int aufs_read_lock(struct dentry *dentry, int flags)
229 struct super_block *sb;
232 err = si_read_lock(sb, flags);
236 if (au_ftest_lock(flags, DW))
237 di_write_lock_child(dentry);
239 di_read_lock_child(dentry, flags);
241 if (au_ftest_lock(flags, GEN)) {
242 err = au_digen_test(dentry, au_sigen(sb));
243 AuDebugOn(!err && au_dbrange_test(dentry));
245 aufs_read_unlock(dentry, flags);
252 void aufs_read_unlock(struct dentry *dentry, int flags)
254 if (au_ftest_lock(flags, DW))
255 di_write_unlock(dentry);
257 di_read_unlock(dentry, flags);
258 si_read_unlock(dentry->d_sb);
261 void aufs_write_lock(struct dentry *dentry)
263 si_write_lock(dentry->d_sb, AuLock_FLUSH | AuLock_NOPLMW);
264 di_write_lock_child(dentry);
267 void aufs_write_unlock(struct dentry *dentry)
269 di_write_unlock(dentry);
270 si_write_unlock(dentry->d_sb);
273 int aufs_read_and_write_lock2(struct dentry *d1, struct dentry *d2, int flags)
277 struct super_block *sb;
280 err = si_read_lock(sb, flags);
284 di_write_lock2_child(d1, d2, au_ftest_lock(flags, DIR));
286 if (au_ftest_lock(flags, GEN)) {
287 sigen = au_sigen(sb);
288 err = au_digen_test(d1, sigen);
289 AuDebugOn(!err && au_dbrange_test(d1));
291 err = au_digen_test(d2, sigen);
292 AuDebugOn(!err && au_dbrange_test(d2));
295 aufs_read_and_write_unlock2(d1, d2);
302 void aufs_read_and_write_unlock2(struct dentry *d1, struct dentry *d2)
304 di_write_unlock2(d1, d2);
305 si_read_unlock(d1->d_sb);
308 /* ---------------------------------------------------------------------- */
310 int si_pid_test_slow(struct super_block *sb)
315 p = radix_tree_lookup(&au_sbi(sb)->au_si_pid.tree, current->pid);
321 void si_pid_set_slow(struct super_block *sb)
324 struct au_sbinfo *sbinfo;
326 AuDebugOn(si_pid_test_slow(sb));
329 err = radix_tree_preload(GFP_NOFS | __GFP_NOFAIL);
331 spin_lock(&sbinfo->au_si_pid.tree_lock);
332 err = radix_tree_insert(&sbinfo->au_si_pid.tree, current->pid,
333 /*any valid ptr*/sb);
334 spin_unlock(&sbinfo->au_si_pid.tree_lock);
336 radix_tree_preload_end();
339 void si_pid_clr_slow(struct super_block *sb)
342 struct au_sbinfo *sbinfo;
344 AuDebugOn(!si_pid_test_slow(sb));
347 spin_lock(&sbinfo->au_si_pid.tree_lock);
348 p = radix_tree_delete(&sbinfo->au_si_pid.tree, current->pid);
349 spin_unlock(&sbinfo->au_si_pid.tree_lock);