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#ifndef __LINUX_DCACHE_H
#define __LINUX_DCACHE_H
#include <linux/atomic.h>
#include <linux/list.h>
#include <linux/rculist.h>
#include <linux/rculist_bl.h>
#include <linux/spinlock.h>
#include <linux/seqlock.h>
#include <linux/cache.h>
#include <linux/rcupdate.h>
struct nameidata;
struct path;
struct vfsmount;
/*
* linux/include/linux/dcache.h
*
* Dirent cache data structures
*
* (C) Copyright 1997 Thomas Schoebel-Theuer,
* with heavy changes by Linus Torvalds
*/
#define IS_ROOT(x) ((x) == (x)->d_parent)
struct qstr {
unsigned int hash;
unsigned int len;
const unsigned char *name;
};
struct dentry_stat_t {
int nr_dentry;
int nr_unused;
int age_limit;
int want_pages;
int dummy[2];
};
extern struct dentry_stat_t dentry_stat;
#define init_name_hash() 0
static inline unsigned long
partial_name_hash(unsigned long c, unsigned long prevhash)
{
return (prevhash + (c << 4) + (c >> 4)) * 11;
}
static inline unsigned long end_name_hash(unsigned long hash)
{
return (unsigned int) hash;
}
extern unsigned int full_name_hash(const unsigned char *, unsigned int);
#ifdef CONFIG_64BIT
# define DNAME_INLINE_LEN 32
#else
# ifdef CONFIG_SMP
# define DNAME_INLINE_LEN 36
# else
# define DNAME_INLINE_LEN 40
# endif
#endif
struct dentry {
unsigned int d_flags;
seqcount_t d_seq;
struct hlist_bl_node d_hash;
struct dentry *d_parent;
struct qstr d_name;
struct inode *d_inode;
unsigned char d_iname[DNAME_INLINE_LEN];
unsigned int d_count;
spinlock_t d_lock;
const struct dentry_operations *d_op;
struct super_block *d_sb;
unsigned long d_time;
void *d_fsdata;
struct list_head d_lru;
union {
struct list_head d_child;
struct rcu_head d_rcu;
} d_u;
struct list_head d_subdirs;
struct list_head d_alias;
};
enum dentry_d_lock_class
{
DENTRY_D_LOCK_NORMAL,
DENTRY_D_LOCK_NESTED
};
struct dentry_operations {
int (*d_revalidate)(struct dentry *, struct nameidata *);
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 *,
unsigned int, const char *, const struct qstr *);
int (*d_delete)(const 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);
} ____cacheline_aligned;
#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_DISCONNECTED 0x0020
#define DCACHE_REFERENCED 0x0040
#define DCACHE_RCUACCESS 0x0080
#define DCACHE_CANT_MOUNT 0x0100
#define DCACHE_GENOCIDE 0x0200
#define DCACHE_SHRINK_LIST 0x0400
#define DCACHE_NFSFS_RENAMED 0x1000
#define DCACHE_COOKIE 0x2000
#define DCACHE_FSNOTIFY_PARENT_WATCHED 0x4000
#define DCACHE_MOUNTED 0x10000
#define DCACHE_NEED_AUTOMOUNT 0x20000
#define DCACHE_MANAGE_TRANSIT 0x40000
#define DCACHE_NEED_LOOKUP 0x80000
#define DCACHE_MANAGED_DENTRY \
(DCACHE_MOUNTED|DCACHE_NEED_AUTOMOUNT|DCACHE_MANAGE_TRANSIT)
extern seqlock_t rename_lock;
static inline int dname_external(struct dentry *dentry)
{
return dentry->d_name.name != dentry->d_iname;
}
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 void __d_drop(struct dentry *dentry);
extern void d_drop(struct dentry *dentry);
extern void d_delete(struct dentry *);
extern void d_set_d_op(struct dentry *dentry, const struct dentry_operations *op);
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_splice_alias(struct inode *, struct dentry *);
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 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 struct dentry * d_make_root(struct inode *);
extern void d_genocide(struct dentry *);
extern struct dentry *d_find_alias(struct inode *);
extern void d_prune_aliases(struct inode *);
extern int have_submounts(struct dentry *);
extern void d_rehash(struct dentry *);
static inline void d_add(struct dentry *entry, struct inode *inode)
{
d_instantiate(entry, inode);
d_rehash(entry);
}
static inline struct dentry *d_add_unique(struct dentry *entry, struct inode *inode)
{
struct dentry *res;
res = d_instantiate_unique(entry, inode);
d_rehash(res != NULL ? res : entry);
return res;
}
extern void dentry_update_name_case(struct dentry *, struct qstr *);
extern void d_move(struct dentry *, struct dentry *);
extern struct dentry *d_ancestor(struct dentry *, struct dentry *);
extern struct dentry *d_lookup(struct dentry *, struct qstr *);
extern struct dentry *d_hash_and_lookup(struct dentry *, struct qstr *);
extern struct dentry *__d_lookup(struct dentry *, struct qstr *);
extern struct dentry *__d_lookup_rcu(const struct dentry *parent,
const struct qstr *name,
unsigned *seq, struct inode **inode);
static inline int __d_rcu_to_refcount(struct dentry *dentry, unsigned seq)
{
int ret = 0;
assert_spin_locked(&dentry->d_lock);
if (!read_seqcount_retry(&dentry->d_seq, seq)) {
ret = 1;
dentry->d_count++;
}
return ret;
}
extern int d_validate(struct dentry *, struct dentry *);
extern char *dynamic_dname(struct dentry *, char *, int, const char *, ...);
extern char *__d_path(const struct path *, const struct path *, char *, int);
extern char *d_absolute_path(const struct path *, char *, int);
extern char *d_path(const struct path *, char *, int);
extern char *d_path_with_unreachable(const struct path *, char *, int);
extern char *dentry_path_raw(struct dentry *, char *, int);
extern char *dentry_path(struct dentry *, char *, int);
static inline struct dentry *dget_dlock(struct dentry *dentry)
{
if (dentry)
dentry->d_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);
}
return dentry;
}
extern struct dentry *dget_parent(struct dentry *dentry);
static inline int d_unhashed(struct dentry *dentry)
{
return hlist_bl_unhashed(&dentry->d_hash);
}
static inline int d_unlinked(struct dentry *dentry)
{
return d_unhashed(dentry) && !IS_ROOT(dentry);
}
static inline int cant_mount(struct dentry *dentry)
{
return (dentry->d_flags & DCACHE_CANT_MOUNT);
}
static inline void dont_mount(struct dentry *dentry)
{
spin_lock(&dentry->d_lock);
dentry->d_flags |= DCACHE_CANT_MOUNT;
spin_unlock(&dentry->d_lock);
}
extern void dput(struct dentry *);
static inline bool d_managed(struct dentry *dentry)
{
return dentry->d_flags & DCACHE_MANAGED_DENTRY;
}
static inline bool d_mountpoint(struct dentry *dentry)
{
return dentry->d_flags & DCACHE_MOUNTED;
}
static inline bool d_need_lookup(struct dentry *dentry)
{
return dentry->d_flags & DCACHE_NEED_LOOKUP;
}
extern void d_clear_need_lookup(struct dentry *dentry);
extern int sysctl_vfs_cache_pressure;
#endif
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