| /* |
| * Copyright (C) 2005-2013 Junjiro R. Okajima |
| * |
| * This program, aufs is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA |
| */ |
| |
| /* |
| * lookup and dentry operations |
| */ |
| |
| #ifndef __AUFS_DENTRY_H__ |
| #define __AUFS_DENTRY_H__ |
| |
| #ifdef __KERNEL__ |
| |
| #include <linux/dcache.h> |
| #include "rwsem.h" |
| |
| struct au_hdentry { |
| struct dentry *hd_dentry; |
| aufs_bindex_t hd_id; |
| }; |
| |
| struct au_dinfo { |
| atomic_t di_generation; |
| |
| struct au_rwsem di_rwsem; |
| aufs_bindex_t di_bstart, di_bend, di_bwh, di_bdiropq; |
| struct au_hdentry *di_hdentry; |
| } ____cacheline_aligned_in_smp; |
| |
| /* ---------------------------------------------------------------------- */ |
| |
| /* dentry.c */ |
| extern const struct dentry_operations aufs_dop; |
| struct au_branch; |
| struct dentry *au_sio_lkup_one(struct qstr *name, struct dentry *parent, |
| struct au_branch *br); |
| int au_h_verify(struct dentry *h_dentry, unsigned int udba, struct inode *h_dir, |
| struct dentry *h_parent, struct au_branch *br); |
| |
| int au_lkup_dentry(struct dentry *dentry, aufs_bindex_t bstart, mode_t type); |
| int au_lkup_neg(struct dentry *dentry, aufs_bindex_t bindex, int wh); |
| int au_refresh_dentry(struct dentry *dentry, struct dentry *parent); |
| int au_reval_dpath(struct dentry *dentry, unsigned int sigen); |
| |
| /* dinfo.c */ |
| void au_di_init_once(void *_di); |
| struct au_dinfo *au_di_alloc(struct super_block *sb, unsigned int lsc); |
| void au_di_free(struct au_dinfo *dinfo); |
| void au_di_swap(struct au_dinfo *a, struct au_dinfo *b); |
| void au_di_cp(struct au_dinfo *dst, struct au_dinfo *src); |
| int au_di_init(struct dentry *dentry); |
| void au_di_fin(struct dentry *dentry); |
| int au_di_realloc(struct au_dinfo *dinfo, int nbr); |
| |
| void di_read_lock(struct dentry *d, int flags, unsigned int lsc); |
| void di_read_unlock(struct dentry *d, int flags); |
| void di_downgrade_lock(struct dentry *d, int flags); |
| void di_write_lock(struct dentry *d, unsigned int lsc); |
| void di_write_unlock(struct dentry *d); |
| void di_write_lock2_child(struct dentry *d1, struct dentry *d2, int isdir); |
| void di_write_lock2_parent(struct dentry *d1, struct dentry *d2, int isdir); |
| void di_write_unlock2(struct dentry *d1, struct dentry *d2); |
| |
| struct dentry *au_h_dptr(struct dentry *dentry, aufs_bindex_t bindex); |
| struct dentry *au_h_d_alias(struct dentry *dentry, aufs_bindex_t bindex); |
| aufs_bindex_t au_dbtail(struct dentry *dentry); |
| aufs_bindex_t au_dbtaildir(struct dentry *dentry); |
| |
| void au_set_h_dptr(struct dentry *dentry, aufs_bindex_t bindex, |
| struct dentry *h_dentry); |
| int au_digen_test(struct dentry *dentry, unsigned int sigen); |
| int au_dbrange_test(struct dentry *dentry); |
| void au_update_digen(struct dentry *dentry); |
| void au_update_dbrange(struct dentry *dentry, int do_put_zero); |
| void au_update_dbstart(struct dentry *dentry); |
| void au_update_dbend(struct dentry *dentry); |
| int au_find_dbindex(struct dentry *dentry, struct dentry *h_dentry); |
| |
| /* ---------------------------------------------------------------------- */ |
| |
| static inline struct au_dinfo *au_di(struct dentry *dentry) |
| { |
| return dentry->d_fsdata; |
| } |
| |
| /* ---------------------------------------------------------------------- */ |
| |
| /* lock subclass for dinfo */ |
| enum { |
| AuLsc_DI_CHILD, /* child first */ |
| AuLsc_DI_CHILD2, /* rename(2), link(2), and cpup at hnotify */ |
| AuLsc_DI_CHILD3, /* copyup dirs */ |
| AuLsc_DI_PARENT, |
| AuLsc_DI_PARENT2, |
| AuLsc_DI_PARENT3, |
| AuLsc_DI_TMP /* temp for replacing dinfo */ |
| }; |
| |
| /* |
| * di_read_lock_child, di_write_lock_child, |
| * di_read_lock_child2, di_write_lock_child2, |
| * di_read_lock_child3, di_write_lock_child3, |
| * di_read_lock_parent, di_write_lock_parent, |
| * di_read_lock_parent2, di_write_lock_parent2, |
| * di_read_lock_parent3, di_write_lock_parent3, |
| */ |
| #define AuReadLockFunc(name, lsc) \ |
| static inline void di_read_lock_##name(struct dentry *d, int flags) \ |
| { di_read_lock(d, flags, AuLsc_DI_##lsc); } |
| |
| #define AuWriteLockFunc(name, lsc) \ |
| static inline void di_write_lock_##name(struct dentry *d) \ |
| { di_write_lock(d, AuLsc_DI_##lsc); } |
| |
| #define AuRWLockFuncs(name, lsc) \ |
| AuReadLockFunc(name, lsc) \ |
| AuWriteLockFunc(name, lsc) |
| |
| AuRWLockFuncs(child, CHILD); |
| AuRWLockFuncs(child2, CHILD2); |
| AuRWLockFuncs(child3, CHILD3); |
| AuRWLockFuncs(parent, PARENT); |
| AuRWLockFuncs(parent2, PARENT2); |
| AuRWLockFuncs(parent3, PARENT3); |
| |
| #undef AuReadLockFunc |
| #undef AuWriteLockFunc |
| #undef AuRWLockFuncs |
| |
| #define DiMustNoWaiters(d) AuRwMustNoWaiters(&au_di(d)->di_rwsem) |
| #define DiMustAnyLock(d) AuRwMustAnyLock(&au_di(d)->di_rwsem) |
| #define DiMustWriteLock(d) AuRwMustWriteLock(&au_di(d)->di_rwsem) |
| |
| /* ---------------------------------------------------------------------- */ |
| |
| /* todo: memory barrier? */ |
| static inline unsigned int au_digen(struct dentry *d) |
| { |
| return atomic_read(&au_di(d)->di_generation); |
| } |
| |
| static inline void au_h_dentry_init(struct au_hdentry *hdentry) |
| { |
| hdentry->hd_dentry = NULL; |
| } |
| |
| static inline void au_hdput(struct au_hdentry *hd) |
| { |
| if (hd) |
| dput(hd->hd_dentry); |
| } |
| |
| static inline aufs_bindex_t au_dbstart(struct dentry *dentry) |
| { |
| DiMustAnyLock(dentry); |
| return au_di(dentry)->di_bstart; |
| } |
| |
| static inline aufs_bindex_t au_dbend(struct dentry *dentry) |
| { |
| DiMustAnyLock(dentry); |
| return au_di(dentry)->di_bend; |
| } |
| |
| static inline aufs_bindex_t au_dbwh(struct dentry *dentry) |
| { |
| DiMustAnyLock(dentry); |
| return au_di(dentry)->di_bwh; |
| } |
| |
| static inline aufs_bindex_t au_dbdiropq(struct dentry *dentry) |
| { |
| DiMustAnyLock(dentry); |
| return au_di(dentry)->di_bdiropq; |
| } |
| |
| /* todo: hard/soft set? */ |
| static inline void au_set_dbstart(struct dentry *dentry, aufs_bindex_t bindex) |
| { |
| DiMustWriteLock(dentry); |
| au_di(dentry)->di_bstart = bindex; |
| } |
| |
| static inline void au_set_dbend(struct dentry *dentry, aufs_bindex_t bindex) |
| { |
| DiMustWriteLock(dentry); |
| au_di(dentry)->di_bend = bindex; |
| } |
| |
| static inline void au_set_dbwh(struct dentry *dentry, aufs_bindex_t bindex) |
| { |
| DiMustWriteLock(dentry); |
| /* dbwh can be outside of bstart - bend range */ |
| au_di(dentry)->di_bwh = bindex; |
| } |
| |
| static inline void au_set_dbdiropq(struct dentry *dentry, aufs_bindex_t bindex) |
| { |
| DiMustWriteLock(dentry); |
| au_di(dentry)->di_bdiropq = bindex; |
| } |
| |
| /* ---------------------------------------------------------------------- */ |
| |
| #ifdef CONFIG_AUFS_HNOTIFY |
| static inline void au_digen_dec(struct dentry *d) |
| { |
| atomic_dec(&au_di(d)->di_generation); |
| } |
| |
| static inline void au_hn_di_reinit(struct dentry *dentry) |
| { |
| dentry->d_fsdata = NULL; |
| } |
| #else |
| AuStubVoid(au_hn_di_reinit, struct dentry *dentry __maybe_unused) |
| #endif /* CONFIG_AUFS_HNOTIFY */ |
| |
| #endif /* __KERNEL__ */ |
| #endif /* __AUFS_DENTRY_H__ */ |
