--- zzzz-none-000/linux-3.10.107/include/linux/dcache.h 2017-06-27 09:49:32.000000000 +0000 +++ scorpion-7490-727/linux-3.10.107/include/linux/dcache.h 2021-02-04 17:41:59.000000000 +0000 @@ -9,8 +9,8 @@ #include #include #include +#include -struct nameidata; struct path; struct vfsmount; @@ -28,8 +28,10 @@ /* The hash is always the low bits of hash_len */ #ifdef __LITTLE_ENDIAN #define HASH_LEN_DECLARE u32 hash; u32 len; + #define bytemask_from_count(cnt) (~(~0ul << (cnt)*8)) #else #define HASH_LEN_DECLARE u32 len; u32 hash; + #define bytemask_from_count(cnt) (~(~0ul >> (cnt)*8)) #endif /* @@ -52,13 +54,14 @@ #define QSTR_INIT(n,l) { { { .len = l } }, .name = n } #define hashlen_hash(hashlen) ((u32) (hashlen)) #define hashlen_len(hashlen) ((u32)((hashlen) >> 32)) +#define hashlen_create(hash,len) (((u64)(len)<<32)|(u32)(hash)) struct dentry_stat_t { - int nr_dentry; - int nr_unused; - int age_limit; /* age in seconds */ - int want_pages; /* pages requested by system */ - int dummy[2]; + long nr_dentry; + long nr_unused; + long age_limit; /* age in seconds */ + long want_pages; /* pages requested by system */ + long dummy[2]; }; extern struct dentry_stat_t dentry_stat; @@ -100,6 +103,8 @@ # endif #endif +#define d_lock d_lockref.lock + struct dentry { /* RCU lookup touched fields */ unsigned int d_flags; /* protected by d_lock */ @@ -112,8 +117,7 @@ unsigned char d_iname[DNAME_INLINE_LEN]; /* small names */ /* Ref lookup also touches following */ - unsigned int d_count; /* protected by d_lock */ - spinlock_t d_lock; /* per dentry lock */ + struct lockref d_lockref; /* per-dentry lock and refcount */ const struct dentry_operations *d_op; struct super_block *d_sb; /* The root of the dentry tree */ unsigned long d_time; /* used by d_revalidate */ @@ -146,10 +150,8 @@ struct dentry_operations { int (*d_revalidate)(struct dentry *, unsigned int); int (*d_weak_revalidate)(struct dentry *, unsigned int); - int (*d_hash)(const struct dentry *, const struct inode *, - struct qstr *); - int (*d_compare)(const struct dentry *, const struct inode *, - const struct dentry *, const struct inode *, + int (*d_hash)(const struct dentry *, struct qstr *); + int (*d_compare)(const struct dentry *, const struct dentry *, unsigned int, const char *, const struct qstr *); int (*d_delete)(const struct dentry *); void (*d_release)(struct dentry *); @@ -158,6 +160,8 @@ char *(*d_dname)(struct dentry *, char *, int); struct vfsmount *(*d_automount)(struct path *); int (*d_manage)(struct dentry *, bool); + struct inode *(*d_select_inode)(struct dentry *, unsigned); + struct dentry *(*d_real)(struct dentry *, struct inode *); } ____cacheline_aligned; /* @@ -169,13 +173,13 @@ */ /* 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 @@ -186,43 +190,55 @@ * 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_FSNOTIFY_PARENT_WATCHED_RECURSIVLY 0x10000000 + +#define DCACHE_DENTRY_KILLED 0x00008000 -#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_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_DENTRY_KILLED 0x100000 +#define DCACHE_LRU_LIST 0x00080000 -extern seqlock_t rename_lock; +#define DCACHE_ENTRY_TYPE 0x00700000 +#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 */ +#define DCACHE_OP_SELECT_INODE 0x02000000 /* Unioned entry: dcache op selects inode */ +#define DCACHE_OP_REAL 0x08000000 -static inline int dname_external(struct dentry *dentry) -{ - return dentry->d_name.name != dentry->d_iname; -} +extern seqlock_t rename_lock; /* * These are the low-level FS interfaces to the dcache.. */ extern void d_instantiate(struct dentry *, struct inode *); extern struct dentry * d_instantiate_unique(struct dentry *, struct inode *); -extern struct dentry * d_materialise_unique(struct dentry *, struct inode *); +extern int d_instantiate_no_diralias(struct dentry *, struct inode *); extern void __d_drop(struct dentry *dentry); extern void d_drop(struct dentry *dentry); extern void d_delete(struct dentry *); @@ -235,10 +251,11 @@ extern struct dentry * d_add_ci(struct dentry *, struct inode *, struct qstr *); extern struct dentry *d_find_any_alias(struct inode *inode); extern struct dentry * d_obtain_alias(struct inode *); +extern struct dentry * d_obtain_root(struct inode *); extern void shrink_dcache_sb(struct super_block *); extern void shrink_dcache_parent(struct dentry *); extern void shrink_dcache_for_umount(struct super_block *); -extern int d_invalidate(struct dentry *); +extern void d_invalidate(struct dentry *); /* only used at mount-time */ extern struct dentry * d_make_root(struct inode *); @@ -246,6 +263,8 @@ /* - the ramfs-type tree */ extern void d_genocide(struct dentry *); +extern void d_tmpfile(struct dentry *, struct inode *); + extern struct dentry *d_find_alias(struct inode *); extern void d_prune_aliases(struct inode *); @@ -293,6 +312,7 @@ /* used for rename() and baskets */ extern void d_move(struct dentry *, struct dentry *); +extern void d_exchange(struct dentry *, struct dentry *); extern struct dentry *d_ancestor(struct dentry *, struct dentry *); /* appendix may either be NULL or be used for transname suffixes */ @@ -300,38 +320,18 @@ extern struct dentry *d_hash_and_lookup(struct dentry *, struct qstr *); extern struct dentry *__d_lookup(const struct dentry *, const struct qstr *); extern struct dentry *__d_lookup_rcu(const struct dentry *parent, - const struct qstr *name, - unsigned *seq, struct inode *inode); + const struct qstr *name, unsigned *seq); -/** - * __d_rcu_to_refcount - take a refcount on dentry if sequence check is ok - * @dentry: dentry to take a ref on - * @seq: seqcount to verify against - * Returns: 0 on failure, else 1. - * - * __d_rcu_to_refcount operates on a dentry,seq pair that was returned - * by __d_lookup_rcu, to get a reference on an rcu-walk dentry. - */ -static inline int __d_rcu_to_refcount(struct dentry *dentry, unsigned seq) +static inline unsigned d_count(const struct dentry *dentry) { - int ret = 0; - - assert_spin_locked(&dentry->d_lock); - if (!read_seqcount_retry(&dentry->d_seq, seq)) { - ret = 1; - dentry->d_count++; - } - - return ret; + return dentry->d_lockref.count; } -/* validate "insecure" dentry pointer */ -extern int d_validate(struct dentry *, struct dentry *); - /* * helper function for dentry_operations.d_dname() members */ -extern char *dynamic_dname(struct dentry *, char *, int, const char *, ...); +extern __printf(4, 5) +char *dynamic_dname(struct dentry *, char *, int, const char *, ...); extern char *simple_dname(struct dentry *, char *, int); extern char *__d_path(const struct path *, const struct path *, char *, int); @@ -353,17 +353,14 @@ static inline struct dentry *dget_dlock(struct dentry *dentry) { if (dentry) - dentry->d_count++; + dentry->d_lockref.count++; return dentry; } static inline struct dentry *dget(struct dentry *dentry) { - if (dentry) { - spin_lock(&dentry->d_lock); - dget_dlock(dentry); - spin_unlock(&dentry->d_lock); - } + if (dentry) + lockref_get(&dentry->d_lockref); return dentry; } @@ -376,17 +373,17 @@ * Returns true if the dentry passed is not currently hashed. */ -static inline int d_unhashed(struct dentry *dentry) +static inline int d_unhashed(const struct dentry *dentry) { return hlist_bl_unhashed(&dentry->d_hash); } -static inline int d_unlinked(struct dentry *dentry) +static inline int d_unlinked(const struct dentry *dentry) { return d_unhashed(dentry) && !IS_ROOT(dentry); } -static inline int cant_mount(struct dentry *dentry) +static inline int cant_mount(const struct dentry *dentry) { return (dentry->d_flags & DCACHE_CANT_MOUNT); } @@ -400,16 +397,230 @@ extern void dput(struct dentry *); -static inline bool d_managed(struct dentry *dentry) +static inline bool d_managed(const struct dentry *dentry) { return dentry->d_flags & DCACHE_MANAGED_DENTRY; } -static inline bool d_mountpoint(struct dentry *dentry) +static inline bool d_mountpoint(const struct dentry *dentry) { return dentry->d_flags & DCACHE_MOUNTED; } +/* + * Directory cache entry type accessor functions. + */ +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; +} + +static inline bool d_is_autodir(const struct dentry *dentry) +{ + return __d_entry_type(dentry) == DCACHE_AUTODIR_TYPE; +} + +static inline bool d_is_dir(const struct dentry *dentry) +{ + return d_can_lookup(dentry) || d_is_autodir(dentry); +} + +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_is_reg(dentry) || d_is_special(dentry); +} + +static inline bool d_is_negative(const struct dentry *dentry) +{ + // TODO: check d_is_whiteout(dentry) also. + return d_is_miss(dentry); +} + +static inline bool d_is_positive(const struct dentry *dentry) +{ + return !d_is_negative(dentry); +} + +/** + * d_really_is_negative - Determine if a dentry is really negative (ignoring fallthroughs) + * @dentry: The dentry in question + * + * Returns true if the dentry represents either an absent name or a name that + * doesn't map to an inode (ie. ->d_inode is NULL). The dentry could represent + * a true miss, a whiteout that isn't represented by a 0,0 chardev or a + * fallthrough marker in an opaque directory. + * + * Note! (1) This should be used *only* by a filesystem to examine its own + * dentries. It should not be used to look at some other filesystem's + * dentries. (2) It should also be used in combination with d_inode() to get + * the inode. (3) The dentry may have something attached to ->d_lower and the + * type field of the flags may be set to something other than miss or whiteout. + */ +static inline bool d_really_is_negative(const struct dentry *dentry) +{ + return dentry->d_inode == NULL; +} + +/** + * d_really_is_positive - Determine if a dentry is really positive (ignoring fallthroughs) + * @dentry: The dentry in question + * + * Returns true if the dentry represents a name that maps to an inode + * (ie. ->d_inode is not NULL). The dentry might still represent a whiteout if + * that is represented on medium as a 0,0 chardev. + * + * Note! (1) This should be used *only* by a filesystem to examine its own + * dentries. It should not be used to look at some other filesystem's + * dentries. (2) It should also be used in combination with d_inode() to get + * the inode. + */ +static inline bool d_really_is_positive(const struct dentry *dentry) +{ + return dentry->d_inode != NULL; +} + +static inline int simple_positive(struct dentry *dentry) +{ + return d_really_is_positive(dentry) && !d_unhashed(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; +} + +static inline struct dentry *d_real(struct dentry *dentry) +{ + if (unlikely(dentry->d_flags & DCACHE_OP_REAL)) + return dentry->d_op->d_real(dentry, NULL); + else + return dentry; +} + +static inline struct inode *vfs_select_inode(struct dentry *dentry, + unsigned open_flags) +{ + struct inode *inode = d_inode(dentry); + + if (inode && unlikely(dentry->d_flags & DCACHE_OP_SELECT_INODE)) + inode = dentry->d_op->d_select_inode(dentry, open_flags); + + return inode; +} + +/** + * d_real_inode - Return the real inode + * @dentry: The dentry to query + * + * If dentry is on an union/overlay, then return the underlying, real inode. + * Otherwise return d_inode(). + */ +static inline struct inode *d_real_inode(struct dentry *dentry) +{ + return d_backing_inode(d_real(dentry)); +} + +struct name_snapshot { + const char *name; + char inline_name[DNAME_INLINE_LEN]; +}; +void take_dentry_name_snapshot(struct name_snapshot *, struct dentry *); +void release_dentry_name_snapshot(struct name_snapshot *); + #endif /* __LINUX_DCACHE_H */