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Diffstat (limited to 'include/linux/dcache.h')
-rw-r--r--include/linux/dcache.h101
1 files changed, 57 insertions, 44 deletions
diff --git a/include/linux/dcache.h b/include/linux/dcache.h
index 7e9422cb5989..5ff3e9a4fe5f 100644
--- a/include/linux/dcache.h
+++ b/include/linux/dcache.h
@@ -10,6 +10,7 @@
#include <linux/cache.h>
#include <linux/rcupdate.h>
#include <linux/lockref.h>
+#include <linux/stringhash.h>
struct path;
struct vfsmount;
@@ -52,9 +53,6 @@ struct qstr {
};
#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 {
long nr_dentry;
@@ -65,29 +63,6 @@ struct dentry_stat_t {
};
extern struct dentry_stat_t dentry_stat;
-/* Name hashing routines. Initial hash value */
-/* Hash courtesy of the R5 hash in reiserfs modulo sign bits */
-#define init_name_hash() 0
-
-/* partial hash update function. Assume roughly 4 bits per character */
-static inline unsigned long
-partial_name_hash(unsigned long c, unsigned long prevhash)
-{
- return (prevhash + (c << 4) + (c >> 4)) * 11;
-}
-
-/*
- * Finally: cut down the number of bits to a int value (and try to avoid
- * losing bits)
- */
-static inline unsigned long end_name_hash(unsigned long hash)
-{
- return (unsigned int) hash;
-}
-
-/* Compute the hash for a name string. */
-extern unsigned int full_name_hash(const unsigned char *, unsigned int);
-
/*
* Try to keep struct dentry aligned on 64 byte cachelines (this will
* give reasonable cacheline footprint with larger lines without the
@@ -123,7 +98,10 @@ struct dentry {
unsigned long d_time; /* used by d_revalidate */
void *d_fsdata; /* fs-specific data */
- struct list_head d_lru; /* LRU list */
+ union {
+ struct list_head d_lru; /* LRU list */
+ wait_queue_head_t *d_wait; /* in-lookup ones only */
+ };
struct list_head d_child; /* child of parent list */
struct list_head d_subdirs; /* our children */
/*
@@ -131,6 +109,7 @@ struct dentry {
*/
union {
struct hlist_node d_alias; /* inode alias list */
+ struct hlist_bl_node d_in_lookup_hash; /* only for in-lookup ones */
struct rcu_head d_rcu;
} d_u;
};
@@ -151,17 +130,18 @@ struct dentry_operations {
int (*d_revalidate)(struct dentry *, unsigned int);
int (*d_weak_revalidate)(struct dentry *, unsigned int);
int (*d_hash)(const struct dentry *, struct qstr *);
- int (*d_compare)(const struct dentry *, const struct dentry *,
+ int (*d_compare)(const struct dentry *,
unsigned int, const char *, const struct qstr *);
int (*d_delete)(const struct dentry *);
+ int (*d_init)(struct dentry *);
void (*d_release)(struct dentry *);
void (*d_prune)(struct dentry *);
void (*d_iput)(struct dentry *, struct inode *);
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 *);
+ struct dentry *(*d_real)(struct dentry *, const struct inode *,
+ unsigned int);
} ____cacheline_aligned;
/*
@@ -227,10 +207,11 @@ struct dentry_operations {
#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_ENCRYPTED_WITH_KEY 0x02000000 /* dir is encrypted with a valid key */
+#define DCACHE_OP_REAL 0x04000000
-#define DCACHE_ENCRYPTED_WITH_KEY 0x04000000 /* dir is encrypted with a valid key */
-#define DCACHE_OP_REAL 0x08000000
+#define DCACHE_PAR_LOOKUP 0x10000000 /* being looked up (with parent locked shared) */
+#define DCACHE_DENTRY_CURSOR 0x20000000
extern seqlock_t rename_lock;
@@ -248,6 +229,8 @@ extern void d_set_d_op(struct dentry *dentry, const struct dentry_operations *op
/* allocate/de-allocate */
extern struct dentry * d_alloc(struct dentry *, const struct qstr *);
extern struct dentry * d_alloc_pseudo(struct super_block *, const struct qstr *);
+extern struct dentry * d_alloc_parallel(struct dentry *, const struct qstr *,
+ wait_queue_head_t *);
extern struct dentry * d_splice_alias(struct inode *, struct dentry *);
extern struct dentry * d_add_ci(struct dentry *, struct inode *, struct qstr *);
extern struct dentry * d_exact_alias(struct dentry *, struct inode *);
@@ -280,7 +263,7 @@ extern void d_rehash(struct dentry *);
extern void d_add(struct dentry *, struct inode *);
-extern void dentry_update_name_case(struct dentry *, struct qstr *);
+extern void dentry_update_name_case(struct dentry *, const struct qstr *);
/* used for rename() and baskets */
extern void d_move(struct dentry *, struct dentry *);
@@ -367,6 +350,22 @@ static inline void dont_mount(struct dentry *dentry)
spin_unlock(&dentry->d_lock);
}
+extern void __d_lookup_done(struct dentry *);
+
+static inline int d_in_lookup(struct dentry *dentry)
+{
+ return dentry->d_flags & DCACHE_PAR_LOOKUP;
+}
+
+static inline void d_lookup_done(struct dentry *dentry)
+{
+ if (unlikely(d_in_lookup(dentry))) {
+ spin_lock(&dentry->d_lock);
+ __d_lookup_done(dentry);
+ spin_unlock(&dentry->d_lock);
+ }
+}
+
extern void dput(struct dentry *);
static inline bool d_managed(const struct dentry *dentry)
@@ -557,23 +556,37 @@ static inline struct dentry *d_backing_dentry(struct dentry *upper)
return upper;
}
-static inline struct dentry *d_real(struct dentry *dentry)
+/**
+ * d_real - Return the real dentry
+ * @dentry: the dentry to query
+ * @inode: inode to select the dentry from multiple layers (can be NULL)
+ * @flags: open flags to control copy-up behavior
+ *
+ * If dentry is on an union/overlay, then return the underlying, real dentry.
+ * Otherwise return the dentry itself.
+ *
+ * See also: Documentation/filesystems/vfs.txt
+ */
+static inline struct dentry *d_real(struct dentry *dentry,
+ const struct inode *inode,
+ unsigned int flags)
{
if (unlikely(dentry->d_flags & DCACHE_OP_REAL))
- return dentry->d_op->d_real(dentry, NULL);
+ return dentry->d_op->d_real(dentry, inode, flags);
else
return dentry;
}
-static inline struct inode *vfs_select_inode(struct dentry *dentry,
- unsigned open_flags)
+/**
+ * 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)
{
- 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;
+ return d_backing_inode(d_real(dentry, NULL, 0));
}