diff options
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/dcache.h | 103 |
1 files changed, 96 insertions, 7 deletions
diff --git a/include/linux/dcache.h b/include/linux/dcache.h index 92c08cf7670e..d8358799c594 100644 --- a/include/linux/dcache.h +++ b/include/linux/dcache.h @@ -215,13 +215,16 @@ struct dentry_operations { #define DCACHE_LRU_LIST 0x00080000 #define DCACHE_ENTRY_TYPE 0x00700000 -#define DCACHE_MISS_TYPE 0x00000000 /* Negative dentry */ -#define DCACHE_DIRECTORY_TYPE 0x00100000 /* Normal directory */ -#define DCACHE_AUTODIR_TYPE 0x00200000 /* Lookupless directory (presumed automount) */ -#define DCACHE_SYMLINK_TYPE 0x00300000 /* Symlink */ -#define DCACHE_FILE_TYPE 0x00400000 /* Other file type */ +#define DCACHE_MISS_TYPE 0x00000000 /* Negative dentry (maybe fallthru to nowhere) */ +#define DCACHE_WHITEOUT_TYPE 0x00100000 /* Whiteout dentry (stop pathwalk) */ +#define DCACHE_DIRECTORY_TYPE 0x00200000 /* Normal directory */ +#define DCACHE_AUTODIR_TYPE 0x00300000 /* Lookupless directory (presumed automount) */ +#define DCACHE_REGULAR_TYPE 0x00400000 /* Regular file type (or fallthru to such) */ +#define DCACHE_SPECIAL_TYPE 0x00500000 /* Other file type (or fallthru to such) */ +#define DCACHE_SYMLINK_TYPE 0x00600000 /* Symlink (or fallthru to such) */ #define DCACHE_MAY_FREE 0x00800000 +#define DCACHE_FALLTHRU 0x01000000 /* Fall through to lower layer */ extern seqlock_t rename_lock; @@ -423,6 +426,16 @@ static inline unsigned __d_entry_type(const struct dentry *dentry) return dentry->d_flags & DCACHE_ENTRY_TYPE; } +static inline bool d_is_miss(const struct dentry *dentry) +{ + return __d_entry_type(dentry) == DCACHE_MISS_TYPE; +} + +static inline bool d_is_whiteout(const struct dentry *dentry) +{ + return __d_entry_type(dentry) == DCACHE_WHITEOUT_TYPE; +} + static inline bool d_can_lookup(const struct dentry *dentry) { return __d_entry_type(dentry) == DCACHE_DIRECTORY_TYPE; @@ -443,14 +456,25 @@ static inline bool d_is_symlink(const struct dentry *dentry) return __d_entry_type(dentry) == DCACHE_SYMLINK_TYPE; } +static inline bool d_is_reg(const struct dentry *dentry) +{ + return __d_entry_type(dentry) == DCACHE_REGULAR_TYPE; +} + +static inline bool d_is_special(const struct dentry *dentry) +{ + return __d_entry_type(dentry) == DCACHE_SPECIAL_TYPE; +} + static inline bool d_is_file(const struct dentry *dentry) { - return __d_entry_type(dentry) == DCACHE_FILE_TYPE; + return d_is_reg(dentry) || d_is_special(dentry); } static inline bool d_is_negative(const struct dentry *dentry) { - return __d_entry_type(dentry) == DCACHE_MISS_TYPE; + // TODO: check d_is_whiteout(dentry) also. + return d_is_miss(dentry); } static inline bool d_is_positive(const struct dentry *dentry) @@ -458,10 +482,75 @@ static inline bool d_is_positive(const struct dentry *dentry) return !d_is_negative(dentry); } +extern void d_set_fallthru(struct dentry *dentry); + +static inline bool d_is_fallthru(const struct dentry *dentry) +{ + return dentry->d_flags & DCACHE_FALLTHRU; +} + + extern int sysctl_vfs_cache_pressure; static inline unsigned long vfs_pressure_ratio(unsigned long val) { return mult_frac(val, sysctl_vfs_cache_pressure, 100); } + +/** + * d_inode - Get the actual inode of this dentry + * @dentry: The dentry to query + * + * This is the helper normal filesystems should use to get at their own inodes + * in their own dentries and ignore the layering superimposed upon them. + */ +static inline struct inode *d_inode(const struct dentry *dentry) +{ + return dentry->d_inode; +} + +/** + * d_inode_rcu - Get the actual inode of this dentry with ACCESS_ONCE() + * @dentry: The dentry to query + * + * This is the helper normal filesystems should use to get at their own inodes + * in their own dentries and ignore the layering superimposed upon them. + */ +static inline struct inode *d_inode_rcu(const struct dentry *dentry) +{ + return ACCESS_ONCE(dentry->d_inode); +} + +/** + * d_backing_inode - Get upper or lower inode we should be using + * @upper: The upper layer + * + * This is the helper that should be used to get at the inode that will be used + * if this dentry were to be opened as a file. The inode may be on the upper + * dentry or it may be on a lower dentry pinned by the upper. + * + * Normal filesystems should not use this to access their own inodes. + */ +static inline struct inode *d_backing_inode(const struct dentry *upper) +{ + struct inode *inode = upper->d_inode; + + return inode; +} + +/** + * d_backing_dentry - Get upper or lower dentry we should be using + * @upper: The upper layer + * + * This is the helper that should be used to get the dentry of the inode that + * will be used if this dentry were opened as a file. It may be the upper + * dentry or it may be a lower dentry pinned by the upper. + * + * Normal filesystems should not use this to access their own dentries. + */ +static inline struct dentry *d_backing_dentry(struct dentry *upper) +{ + return upper; +} + #endif /* __LINUX_DCACHE_H */ |