[GitHub/LineageOS/android_kernel_motorola_exynos9610.git] / include / linux / file.h

/*
 * Wrapper functions for accessing the file_struct fd array.
 */

#ifndef __LINUX_FILE_H
#define __LINUX_FILE_H

#include <asm/atomic.h>
#include <linux/posix_types.h>
#include <linux/compiler.h>
#include <linux/spinlock.h>
#include <linux/rcupdate.h>
#include <linux/types.h>

/*
 * The default fd array needs to be at least BITS_PER_LONG,
 * as this is the granularity returned by copy_fdset().
 */
#define NR_OPEN_DEFAULT BITS_PER_LONG

/*
 * The embedded_fd_set is a small fd_set,
 * suitable for most tasks (which open <= BITS_PER_LONG files)
 */
struct embedded_fd_set {
	unsigned long fds_bits[1];
};

struct fdtable {
	unsigned int max_fds;
	struct file ** fd;      /* current fd array */
	fd_set *close_on_exec;
	fd_set *open_fds;
	struct rcu_head rcu;
	struct fdtable *next;
};

/*
 * Open file table structure
 */
struct files_struct {
  /*
   * read mostly part
   */
	atomic_t count;
	struct fdtable *fdt;
	struct fdtable fdtab;
  /*
   * written part on a separate cache line in SMP
   */
	spinlock_t file_lock ____cacheline_aligned_in_smp;
	int next_fd;
	struct embedded_fd_set close_on_exec_init;
	struct embedded_fd_set open_fds_init;
	struct file * fd_array[NR_OPEN_DEFAULT];
};

#define files_fdtable(files) (rcu_dereference((files)->fdt))

extern struct kmem_cache *filp_cachep;

extern void FASTCALL(__fput(struct file *));
extern void FASTCALL(fput(struct file *));

struct file_operations;
struct vfsmount;
struct dentry;
extern int init_file(struct file *, struct vfsmount *mnt,
		struct dentry *dentry, mode_t mode,
		const struct file_operations *fop);
extern struct file *alloc_file(struct vfsmount *, struct dentry *dentry,
		mode_t mode, const struct file_operations *fop);

static inline void fput_light(struct file *file, int fput_needed)
{
	if (unlikely(fput_needed))
		fput(file);
}

extern struct file * FASTCALL(fget(unsigned int fd));
extern struct file * FASTCALL(fget_light(unsigned int fd, int *fput_needed));
extern void FASTCALL(set_close_on_exec(unsigned int fd, int flag));
extern void put_filp(struct file *);
extern int get_unused_fd(void);
extern int get_unused_fd_flags(int flags);
extern void FASTCALL(put_unused_fd(unsigned int fd));
struct kmem_cache;

extern int expand_files(struct files_struct *, int nr);
extern void free_fdtable_rcu(struct rcu_head *rcu);
extern void __init files_defer_init(void);

static inline void free_fdtable(struct fdtable *fdt)
{
	call_rcu(&fdt->rcu, free_fdtable_rcu);
}

static inline struct file * fcheck_files(struct files_struct *files, unsigned int fd)
{
	struct file * file = NULL;
	struct fdtable *fdt = files_fdtable(files);

	if (fd < fdt->max_fds)
		file = rcu_dereference(fdt->fd[fd]);
	return file;
}

/*
 * Check whether the specified fd has an open file.
 */
#define fcheck(fd)	fcheck_files(current->files, fd)

extern void FASTCALL(fd_install(unsigned int fd, struct file * file));

struct task_struct;

struct files_struct *get_files_struct(struct task_struct *);
void FASTCALL(put_files_struct(struct files_struct *fs));
void reset_files_struct(struct task_struct *, struct files_struct *);

extern struct kmem_cache *files_cachep;

#endif /* __LINUX_FILE_H */
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Wrapper functions for accessing the file_struct fd array.
	3	*/
	4
	5	#ifndef __LINUX_FILE_H
	6	#define __LINUX_FILE_H
	7
	8	#include <asm/atomic.h>
	9	#include <linux/posix_types.h>
	10	#include <linux/compiler.h>
	11	#include <linux/spinlock.h>
ab2af1f5	12	#include <linux/rcupdate.h>
0c9e63fd	13	#include <linux/types.h>
1da177e4 LT	14
	15	/*
	16	* The default fd array needs to be at least BITS_PER_LONG,
	17	* as this is the granularity returned by copy_fdset().
	18	*/
	19	#define NR_OPEN_DEFAULT BITS_PER_LONG
	20
0c9e63fd ED	21	/*
	22	* The embedded_fd_set is a small fd_set,
	23	* suitable for most tasks (which open <= BITS_PER_LONG files)
	24	*/
	25	struct embedded_fd_set {
	26	unsigned long fds_bits[1];
	27	};
	28
badf1662 DS	29	struct fdtable {
badf1662 DS	30	unsigned int max_fds;
badf1662 DS	31	struct file ** fd; /* current fd array */
	32	fd_set *close_on_exec;
	33	fd_set *open_fds;
ab2af1f5	34	struct rcu_head rcu;
ab2af1f5	35	struct fdtable *next;
badf1662 DS	36	};
badf1662 DS	37
1da177e4 LT	38	/*
	39	* Open file table structure
	40	*/
	41	struct files_struct {
0c9e63fd ED	42	/*
	43	* read mostly part
	44	*/
95e861db	45	atomic_t count;
ab2af1f5	46	struct fdtable *fdt;
badf1662	47	struct fdtable fdtab;
0c9e63fd ED	48	/*
	49	* written part on a separate cache line in SMP
	50	*/
	51	spinlock_t file_lock ____cacheline_aligned_in_smp;
	52	int next_fd;
	53	struct embedded_fd_set close_on_exec_init;
	54	struct embedded_fd_set open_fds_init;
95e861db	55	struct file * fd_array[NR_OPEN_DEFAULT];
1da177e4 LT	56	};
1da177e4 LT	57
ab2af1f5	58	#define files_fdtable(files) (rcu_dereference((files)->fdt))
badf1662	59
8b7d91eb CL	60	extern struct kmem_cache *filp_cachep;
8b7d91eb CL	61
1da177e4 LT	62	extern void FASTCALL(__fput(struct file *));
	63	extern void FASTCALL(fput(struct file *));
	64
ce8d2cdf DH	65	struct file_operations;
	66	struct vfsmount;
	67	struct dentry;
	68	extern int init_file(struct file , struct vfsmount mnt,
	69	struct dentry *dentry, mode_t mode,
	70	const struct file_operations *fop);
	71	extern struct file alloc_file(struct vfsmount , struct dentry *dentry,
	72	mode_t mode, const struct file_operations *fop);
	73
1da177e4 LT	74	static inline void fput_light(struct file *file, int fput_needed)
	75	{
	76	if (unlikely(fput_needed))
	77	fput(file);
	78	}
	79
	80	extern struct file * FASTCALL(fget(unsigned int fd));
	81	extern struct file * FASTCALL(fget_light(unsigned int fd, int *fput_needed));
	82	extern void FASTCALL(set_close_on_exec(unsigned int fd, int flag));
	83	extern void put_filp(struct file *);
	84	extern int get_unused_fd(void);
4a19542e	85	extern int get_unused_fd_flags(int flags);
1da177e4	86	extern void FASTCALL(put_unused_fd(unsigned int fd));
2109a2d1	87	struct kmem_cache;
1da177e4	88
1da177e4	89	extern int expand_files(struct files_struct *, int nr);
4fd45812	90	extern void free_fdtable_rcu(struct rcu_head *rcu);
ab2af1f5	91	extern void __init files_defer_init(void);
1da177e4	92
01b2d93c VL	93	static inline void free_fdtable(struct fdtable *fdt)
	94	{
	95	call_rcu(&fdt->rcu, free_fdtable_rcu);
	96	}
	97
1da177e4 LT	98	static inline struct file * fcheck_files(struct files_struct *files, unsigned int fd)
	99	{
	100	struct file * file = NULL;
badf1662	101	struct fdtable *fdt = files_fdtable(files);
1da177e4	102
badf1662	103	if (fd < fdt->max_fds)
ab2af1f5	104	file = rcu_dereference(fdt->fd[fd]);
1da177e4 LT	105	return file;
	106	}
	107
	108	/*
	109	* Check whether the specified fd has an open file.
	110	*/
	111	#define fcheck(fd) fcheck_files(current->files, fd)
	112
	113	extern void FASTCALL(fd_install(unsigned int fd, struct file * file));
	114
	115	struct task_struct;
	116
	117	struct files_struct get_files_struct(struct task_struct );
	118	void FASTCALL(put_files_struct(struct files_struct *fs));
3b9b8ab6	119	void reset_files_struct(struct task_struct , struct files_struct );
1da177e4	120
5d6538fc CL	121	extern struct kmem_cache *files_cachep;
5d6538fc CL	122
1da177e4	123	#endif /* __LINUX_FILE_H */