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 * lookup and dentry operations
23 #ifndef __AUFS_DENTRY_H__
24 #define __AUFS_DENTRY_H__
28 #include <linux/dcache.h>
32 struct dentry *hd_dentry;
37 atomic_t di_generation;
39 struct au_rwsem di_rwsem;
40 aufs_bindex_t di_bstart, di_bend, di_bwh, di_bdiropq;
41 struct au_hdentry *di_hdentry;
42 } ____cacheline_aligned_in_smp;
44 /* ---------------------------------------------------------------------- */
47 extern const struct dentry_operations aufs_dop;
49 struct dentry *au_lkup_one(struct qstr *name, struct dentry *h_parent,
50 struct au_branch *br, struct nameidata *nd);
51 struct dentry *au_sio_lkup_one(struct qstr *name, struct dentry *parent,
52 struct au_branch *br);
53 int au_h_verify(struct dentry *h_dentry, unsigned int udba, struct inode *h_dir,
54 struct dentry *h_parent, struct au_branch *br);
56 int au_lkup_dentry(struct dentry *dentry, aufs_bindex_t bstart, mode_t type,
57 struct nameidata *nd);
58 int au_lkup_neg(struct dentry *dentry, aufs_bindex_t bindex, int wh);
59 int au_refresh_dentry(struct dentry *dentry, struct dentry *parent);
60 int au_reval_dpath(struct dentry *dentry, unsigned int sigen);
63 void au_di_init_once(void *_di);
64 struct au_dinfo *au_di_alloc(struct super_block *sb, unsigned int lsc);
65 void au_di_free(struct au_dinfo *dinfo);
66 void au_di_swap(struct au_dinfo *a, struct au_dinfo *b);
67 void au_di_cp(struct au_dinfo *dst, struct au_dinfo *src);
68 int au_di_init(struct dentry *dentry);
69 void au_di_fin(struct dentry *dentry);
70 int au_di_realloc(struct au_dinfo *dinfo, int nbr);
72 void di_read_lock(struct dentry *d, int flags, unsigned int lsc);
73 void di_read_unlock(struct dentry *d, int flags);
74 void di_downgrade_lock(struct dentry *d, int flags);
75 void di_write_lock(struct dentry *d, unsigned int lsc);
76 void di_write_unlock(struct dentry *d);
77 void di_write_lock2_child(struct dentry *d1, struct dentry *d2, int isdir);
78 void di_write_lock2_parent(struct dentry *d1, struct dentry *d2, int isdir);
79 void di_write_unlock2(struct dentry *d1, struct dentry *d2);
81 struct dentry *au_h_dptr(struct dentry *dentry, aufs_bindex_t bindex);
82 struct dentry *au_h_d_alias(struct dentry *dentry, aufs_bindex_t bindex);
83 aufs_bindex_t au_dbtail(struct dentry *dentry);
84 aufs_bindex_t au_dbtaildir(struct dentry *dentry);
86 void au_set_h_dptr(struct dentry *dentry, aufs_bindex_t bindex,
87 struct dentry *h_dentry);
88 int au_digen_test(struct dentry *dentry, unsigned int sigen);
89 int au_dbrange_test(struct dentry *dentry);
90 void au_update_digen(struct dentry *dentry);
91 void au_update_dbrange(struct dentry *dentry, int do_put_zero);
92 void au_update_dbstart(struct dentry *dentry);
93 void au_update_dbend(struct dentry *dentry);
94 int au_find_dbindex(struct dentry *dentry, struct dentry *h_dentry);
96 /* ---------------------------------------------------------------------- */
98 static inline struct au_dinfo *au_di(struct dentry *dentry)
100 return dentry->d_fsdata;
103 /* ---------------------------------------------------------------------- */
105 /* lock subclass for dinfo */
107 AuLsc_DI_CHILD, /* child first */
108 AuLsc_DI_CHILD2, /* rename(2), link(2), and cpup at hnotify */
109 AuLsc_DI_CHILD3, /* copyup dirs */
113 AuLsc_DI_TMP /* temp for replacing dinfo */
117 * di_read_lock_child, di_write_lock_child,
118 * di_read_lock_child2, di_write_lock_child2,
119 * di_read_lock_child3, di_write_lock_child3,
120 * di_read_lock_parent, di_write_lock_parent,
121 * di_read_lock_parent2, di_write_lock_parent2,
122 * di_read_lock_parent3, di_write_lock_parent3,
124 #define AuReadLockFunc(name, lsc) \
125 static inline void di_read_lock_##name(struct dentry *d, int flags) \
126 { di_read_lock(d, flags, AuLsc_DI_##lsc); }
128 #define AuWriteLockFunc(name, lsc) \
129 static inline void di_write_lock_##name(struct dentry *d) \
130 { di_write_lock(d, AuLsc_DI_##lsc); }
132 #define AuRWLockFuncs(name, lsc) \
133 AuReadLockFunc(name, lsc) \
134 AuWriteLockFunc(name, lsc)
136 AuRWLockFuncs(child, CHILD);
137 AuRWLockFuncs(child2, CHILD2);
138 AuRWLockFuncs(child3, CHILD3);
139 AuRWLockFuncs(parent, PARENT);
140 AuRWLockFuncs(parent2, PARENT2);
141 AuRWLockFuncs(parent3, PARENT3);
143 #undef AuReadLockFunc
144 #undef AuWriteLockFunc
147 #define DiMustNoWaiters(d) AuRwMustNoWaiters(&au_di(d)->di_rwsem)
148 #define DiMustAnyLock(d) AuRwMustAnyLock(&au_di(d)->di_rwsem)
149 #define DiMustWriteLock(d) AuRwMustWriteLock(&au_di(d)->di_rwsem)
151 /* ---------------------------------------------------------------------- */
153 /* todo: memory barrier? */
154 static inline unsigned int au_digen(struct dentry *d)
156 return atomic_read(&au_di(d)->di_generation);
159 static inline void au_h_dentry_init(struct au_hdentry *hdentry)
161 hdentry->hd_dentry = NULL;
164 static inline void au_hdput(struct au_hdentry *hd)
170 static inline aufs_bindex_t au_dbstart(struct dentry *dentry)
172 DiMustAnyLock(dentry);
173 return au_di(dentry)->di_bstart;
176 static inline aufs_bindex_t au_dbend(struct dentry *dentry)
178 DiMustAnyLock(dentry);
179 return au_di(dentry)->di_bend;
182 static inline aufs_bindex_t au_dbwh(struct dentry *dentry)
184 DiMustAnyLock(dentry);
185 return au_di(dentry)->di_bwh;
188 static inline aufs_bindex_t au_dbdiropq(struct dentry *dentry)
190 DiMustAnyLock(dentry);
191 return au_di(dentry)->di_bdiropq;
194 /* todo: hard/soft set? */
195 static inline void au_set_dbstart(struct dentry *dentry, aufs_bindex_t bindex)
197 DiMustWriteLock(dentry);
198 au_di(dentry)->di_bstart = bindex;
201 static inline void au_set_dbend(struct dentry *dentry, aufs_bindex_t bindex)
203 DiMustWriteLock(dentry);
204 au_di(dentry)->di_bend = bindex;
207 static inline void au_set_dbwh(struct dentry *dentry, aufs_bindex_t bindex)
209 DiMustWriteLock(dentry);
210 /* dbwh can be outside of bstart - bend range */
211 au_di(dentry)->di_bwh = bindex;
214 static inline void au_set_dbdiropq(struct dentry *dentry, aufs_bindex_t bindex)
216 DiMustWriteLock(dentry);
217 au_di(dentry)->di_bdiropq = bindex;
220 /* ---------------------------------------------------------------------- */
222 #ifdef CONFIG_AUFS_HNOTIFY
223 static inline void au_digen_dec(struct dentry *d)
225 atomic_dec(&au_di(d)->di_generation);
228 static inline void au_hn_di_reinit(struct dentry *dentry)
230 dentry->d_fsdata = NULL;
233 AuStubVoid(au_hn_di_reinit, struct dentry *dentry __maybe_unused)
234 #endif /* CONFIG_AUFS_HNOTIFY */
236 #endif /* __KERNEL__ */
237 #endif /* __AUFS_DENTRY_H__ */