From b18825a7c8e37a7cf6abb97a12a6ad71af160de7 Mon Sep 17 00:00:00 2001 From: David Howells Date: Thu, 12 Sep 2013 19:22:53 +0100 Subject: VFS: Put a small type field into struct dentry::d_flags Put a type field into struct dentry::d_flags to indicate if the dentry is one of the following types that relate particularly to pathwalk: Miss (negative dentry) Directory "Automount" directory (defective - no i_op->lookup()) Symlink Other (regular, socket, fifo, device) The type field is set to one of the first five types on a dentry by calls to __d_instantiate() and d_obtain_alias() from information in the inode (if one is given). The type is cleared by dentry_unlink_inode() when it reconstitutes an existing dentry as a negative dentry. Accessors provided are: d_set_type(dentry, type) d_is_directory(dentry) d_is_autodir(dentry) d_is_symlink(dentry) d_is_file(dentry) d_is_negative(dentry) d_is_positive(dentry) A bunch of checks in pathname resolution switched to those. Signed-off-by: David Howells Signed-off-by: Al Viro --- include/linux/dcache.h | 103 +++++++++++++++++++++++++++++++++++++++---------- 1 file changed, 83 insertions(+), 20 deletions(-) (limited to 'include/linux/dcache.h') diff --git a/include/linux/dcache.h b/include/linux/dcache.h index 716c3760ee3..57e87e749a4 100644 --- a/include/linux/dcache.h +++ b/include/linux/dcache.h @@ -169,13 +169,13 @@ struct dentry_operations { */ /* d_flags entries */ -#define DCACHE_OP_HASH 0x0001 -#define DCACHE_OP_COMPARE 0x0002 -#define DCACHE_OP_REVALIDATE 0x0004 -#define DCACHE_OP_DELETE 0x0008 -#define DCACHE_OP_PRUNE 0x0010 +#define DCACHE_OP_HASH 0x00000001 +#define DCACHE_OP_COMPARE 0x00000002 +#define DCACHE_OP_REVALIDATE 0x00000004 +#define DCACHE_OP_DELETE 0x00000008 +#define DCACHE_OP_PRUNE 0x00000010 -#define DCACHE_DISCONNECTED 0x0020 +#define DCACHE_DISCONNECTED 0x00000020 /* This dentry is possibly not currently connected to the dcache tree, in * which case its parent will either be itself, or will have this flag as * well. nfsd will not use a dentry with this bit set, but will first @@ -186,30 +186,38 @@ struct dentry_operations { * dentry into place and return that dentry rather than the passed one, * typically using d_splice_alias. */ -#define DCACHE_REFERENCED 0x0040 /* Recently used, don't discard. */ -#define DCACHE_RCUACCESS 0x0080 /* Entry has ever been RCU-visible */ +#define DCACHE_REFERENCED 0x00000040 /* Recently used, don't discard. */ +#define DCACHE_RCUACCESS 0x00000080 /* Entry has ever been RCU-visible */ -#define DCACHE_CANT_MOUNT 0x0100 -#define DCACHE_GENOCIDE 0x0200 -#define DCACHE_SHRINK_LIST 0x0400 +#define DCACHE_CANT_MOUNT 0x00000100 +#define DCACHE_GENOCIDE 0x00000200 +#define DCACHE_SHRINK_LIST 0x00000400 -#define DCACHE_OP_WEAK_REVALIDATE 0x0800 +#define DCACHE_OP_WEAK_REVALIDATE 0x00000800 -#define DCACHE_NFSFS_RENAMED 0x1000 +#define DCACHE_NFSFS_RENAMED 0x00001000 /* this dentry has been "silly renamed" and has to be deleted on the last * dput() */ -#define DCACHE_COOKIE 0x2000 /* For use by dcookie subsystem */ -#define DCACHE_FSNOTIFY_PARENT_WATCHED 0x4000 +#define DCACHE_COOKIE 0x00002000 /* For use by dcookie subsystem */ +#define DCACHE_FSNOTIFY_PARENT_WATCHED 0x00004000 /* Parent inode is watched by some fsnotify listener */ -#define DCACHE_MOUNTED 0x10000 /* is a mountpoint */ -#define DCACHE_NEED_AUTOMOUNT 0x20000 /* handle automount on this dir */ -#define DCACHE_MANAGE_TRANSIT 0x40000 /* manage transit from this dirent */ +#define DCACHE_DENTRY_KILLED 0x00008000 + +#define DCACHE_MOUNTED 0x00010000 /* is a mountpoint */ +#define DCACHE_NEED_AUTOMOUNT 0x00020000 /* handle automount on this dir */ +#define DCACHE_MANAGE_TRANSIT 0x00040000 /* manage transit from this dirent */ #define DCACHE_MANAGED_DENTRY \ (DCACHE_MOUNTED|DCACHE_NEED_AUTOMOUNT|DCACHE_MANAGE_TRANSIT) -#define DCACHE_LRU_LIST 0x80000 -#define DCACHE_DENTRY_KILLED 0x100000 +#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 */ extern seqlock_t rename_lock; @@ -394,6 +402,61 @@ static inline bool d_mountpoint(const struct dentry *dentry) return dentry->d_flags & DCACHE_MOUNTED; } +/* + * Directory cache entry type accessor functions. + */ +static inline void __d_set_type(struct dentry *dentry, unsigned type) +{ + dentry->d_flags = (dentry->d_flags & ~DCACHE_ENTRY_TYPE) | type; +} + +static inline void __d_clear_type(struct dentry *dentry) +{ + __d_set_type(dentry, DCACHE_MISS_TYPE); +} + +static inline void d_set_type(struct dentry *dentry, unsigned type) +{ + spin_lock(&dentry->d_lock); + __d_set_type(dentry, type); + spin_unlock(&dentry->d_lock); +} + +static inline unsigned __d_entry_type(const struct dentry *dentry) +{ + return dentry->d_flags & DCACHE_ENTRY_TYPE; +} + +static inline bool d_is_directory(const struct dentry *dentry) +{ + return __d_entry_type(dentry) == DCACHE_DIRECTORY_TYPE; +} + +static inline bool d_is_autodir(const struct dentry *dentry) +{ + return __d_entry_type(dentry) == DCACHE_AUTODIR_TYPE; +} + +static inline bool d_is_symlink(const struct dentry *dentry) +{ + return __d_entry_type(dentry) == DCACHE_SYMLINK_TYPE; +} + +static inline bool d_is_file(const struct dentry *dentry) +{ + return __d_entry_type(dentry) == DCACHE_FILE_TYPE; +} + +static inline bool d_is_negative(const struct dentry *dentry) +{ + return __d_entry_type(dentry) == DCACHE_MISS_TYPE; +} + +static inline bool d_is_positive(const struct dentry *dentry) +{ + return !d_is_negative(dentry); +} + extern int sysctl_vfs_cache_pressure; static inline unsigned long vfs_pressure_ratio(unsigned long val) -- cgit v1.2.3-70-g09d2