[linux-2.6-block.git] / include / linux / poll.h

#ifndef _LINUX_POLL_H
#define _LINUX_POLL_H

#include <asm/poll.h>

#ifdef __KERNEL__

#include <linux/compiler.h>
#include <linux/ktime.h>
#include <linux/wait.h>
#include <linux/string.h>
#include <linux/fs.h>
#include <asm/uaccess.h>

/* ~832 bytes of stack space used max in sys_select/sys_poll before allocating
   additional memory. */
#define MAX_STACK_ALLOC 832
#define FRONTEND_STACK_ALLOC	256
#define SELECT_STACK_ALLOC	FRONTEND_STACK_ALLOC
#define POLL_STACK_ALLOC	FRONTEND_STACK_ALLOC
#define WQUEUES_STACK_ALLOC	(MAX_STACK_ALLOC - FRONTEND_STACK_ALLOC)
#define N_INLINE_POLL_ENTRIES	(WQUEUES_STACK_ALLOC / sizeof(struct poll_table_entry))

#define DEFAULT_POLLMASK (POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM)

struct poll_table_struct;

/* 
 * structures and helpers for f_op->poll implementations
 */
typedef void (*poll_queue_proc)(struct file *, wait_queue_head_t *, struct poll_table_struct *);

typedef struct poll_table_struct {
	poll_queue_proc qproc;
	unsigned long key;
} poll_table;

static inline void poll_wait(struct file * filp, wait_queue_head_t * wait_address, poll_table *p)
{
	if (p && wait_address)
		p->qproc(filp, wait_address, p);
}

static inline void init_poll_funcptr(poll_table *pt, poll_queue_proc qproc)
{
	pt->qproc = qproc;
	pt->key   = ~0UL; /* all events enabled */
}

struct poll_table_entry {
	struct file *filp;
	unsigned long key;
	wait_queue_t wait;
	wait_queue_head_t *wait_address;
};

/*
 * Structures and helpers for sys_poll/sys_poll
 */
struct poll_wqueues {
	poll_table pt;
	struct poll_table_page *table;
	struct task_struct *polling_task;
	int triggered;
	int error;
	int inline_index;
	struct poll_table_entry inline_entries[N_INLINE_POLL_ENTRIES];
};

extern void poll_initwait(struct poll_wqueues *pwq);
extern void poll_freewait(struct poll_wqueues *pwq);
extern int poll_schedule_timeout(struct poll_wqueues *pwq, int state,
				 ktime_t *expires, unsigned long slack);

static inline int poll_schedule(struct poll_wqueues *pwq, int state)
{
	return poll_schedule_timeout(pwq, state, NULL, 0);
}

/*
 * Scaleable version of the fd_set.
 */

typedef struct {
	unsigned long *in, *out, *ex;
	unsigned long *res_in, *res_out, *res_ex;
} fd_set_bits;

/*
 * How many longwords for "nr" bits?
 */
#define FDS_BITPERLONG	(8*sizeof(long))
#define FDS_LONGS(nr)	(((nr)+FDS_BITPERLONG-1)/FDS_BITPERLONG)
#define FDS_BYTES(nr)	(FDS_LONGS(nr)*sizeof(long))

/*
 * We do a VERIFY_WRITE here even though we are only reading this time:
 * we'll write to it eventually..
 *
 * Use "unsigned long" accesses to let user-mode fd_set's be long-aligned.
 */
static inline
int get_fd_set(unsigned long nr, void __user *ufdset, unsigned long *fdset)
{
	nr = FDS_BYTES(nr);
	if (ufdset)
		return copy_from_user(fdset, ufdset, nr) ? -EFAULT : 0;

	memset(fdset, 0, nr);
	return 0;
}

static inline unsigned long __must_check
set_fd_set(unsigned long nr, void __user *ufdset, unsigned long *fdset)
{
	if (ufdset)
		return __copy_to_user(ufdset, fdset, FDS_BYTES(nr));
	return 0;
}

static inline
void zero_fd_set(unsigned long nr, unsigned long *fdset)
{
	memset(fdset, 0, FDS_BYTES(nr));
}

#define MAX_INT64_SECONDS (((s64)(~((u64)0)>>1)/HZ)-1)

extern int do_select(int n, fd_set_bits *fds, struct timespec *end_time);
extern int do_sys_poll(struct pollfd __user * ufds, unsigned int nfds,
		       struct timespec *end_time);
extern int core_sys_select(int n, fd_set __user *inp, fd_set __user *outp,
			   fd_set __user *exp, struct timespec *end_time);

extern int poll_select_set_timeout(struct timespec *to, long sec, long nsec);

#endif /* KERNEL */

#endif /* _LINUX_POLL_H */
Commit	Line	Data
1da177e4 LT	1	#ifndef _LINUX_POLL_H
	2	#define _LINUX_POLL_H
	3
	4	#include <asm/poll.h>
	5
	6	#ifdef __KERNEL__
	7
	8	#include <linux/compiler.h>
a99bbaf5	9	#include <linux/ktime.h>
1da177e4 LT	10	#include <linux/wait.h>
1da177e4 LT	11	#include <linux/string.h>
f23f6e08	12	#include <linux/fs.h>
1da177e4 LT	13	#include <asm/uaccess.h>
1da177e4 LT	14
70674f95 AK	15	/* ~832 bytes of stack space used max in sys_select/sys_poll before allocating
	16	additional memory. */
	17	#define MAX_STACK_ALLOC 832
	18	#define FRONTEND_STACK_ALLOC 256
	19	#define SELECT_STACK_ALLOC FRONTEND_STACK_ALLOC
	20	#define POLL_STACK_ALLOC FRONTEND_STACK_ALLOC
	21	#define WQUEUES_STACK_ALLOC (MAX_STACK_ALLOC - FRONTEND_STACK_ALLOC)
	22	#define N_INLINE_POLL_ENTRIES (WQUEUES_STACK_ALLOC / sizeof(struct poll_table_entry))
	23
dd23aae4 AD	24	#define DEFAULT_POLLMASK (POLLIN \| POLLOUT \| POLLRDNORM \| POLLWRNORM)
dd23aae4 AD	25
1da177e4 LT	26	struct poll_table_struct;
	27
	28	/*
	29	* structures and helpers for f_op->poll implementations
	30	*/
	31	typedef void (poll_queue_proc)(struct file , wait_queue_head_t , struct poll_table_struct );
	32
	33	typedef struct poll_table_struct {
	34	poll_queue_proc qproc;
4938d7e0	35	unsigned long key;
1da177e4 LT	36	} poll_table;
	37
	38	static inline void poll_wait(struct file * filp, wait_queue_head_t * wait_address, poll_table *p)
	39	{
	40	if (p && wait_address)
	41	p->qproc(filp, wait_address, p);
	42	}
	43
	44	static inline void init_poll_funcptr(poll_table *pt, poll_queue_proc qproc)
	45	{
	46	pt->qproc = qproc;
4938d7e0	47	pt->key = ~0UL; /* all events enabled */
1da177e4 LT	48	}
1da177e4 LT	49
70674f95	50	struct poll_table_entry {
5f820f64	51	struct file *filp;
4938d7e0	52	unsigned long key;
70674f95	53	wait_queue_t wait;
5f820f64	54	wait_queue_head_t *wait_address;
70674f95 AK	55	};
70674f95 AK	56
1da177e4 LT	57	/*
	58	* Structures and helpers for sys_poll/sys_poll
	59	*/
	60	struct poll_wqueues {
	61	poll_table pt;
5f820f64 TH	62	struct poll_table_page *table;
	63	struct task_struct *polling_task;
	64	int triggered;
1da177e4	65	int error;
70674f95 AK	66	int inline_index;
70674f95 AK	67	struct poll_table_entry inline_entries[N_INLINE_POLL_ENTRIES];
1da177e4 LT	68	};
	69
	70	extern void poll_initwait(struct poll_wqueues *pwq);
	71	extern void poll_freewait(struct poll_wqueues *pwq);
5f820f64 TH	72	extern int poll_schedule_timeout(struct poll_wqueues *pwq, int state,
	73	ktime_t *expires, unsigned long slack);
	74
	75	static inline int poll_schedule(struct poll_wqueues *pwq, int state)
	76	{
	77	return poll_schedule_timeout(pwq, state, NULL, 0);
	78	}
1da177e4 LT	79
	80	/*
	81	* Scaleable version of the fd_set.
	82	*/
	83
	84	typedef struct {
	85	unsigned long in, out, *ex;
	86	unsigned long res_in, res_out, *res_ex;
	87	} fd_set_bits;
	88
	89	/*
	90	* How many longwords for "nr" bits?
	91	*/
	92	#define FDS_BITPERLONG (8*sizeof(long))
	93	#define FDS_LONGS(nr) (((nr)+FDS_BITPERLONG-1)/FDS_BITPERLONG)
	94	#define FDS_BYTES(nr) (FDS_LONGS(nr)*sizeof(long))
	95
	96	/*
	97	* We do a VERIFY_WRITE here even though we are only reading this time:
	98	* we'll write to it eventually..
	99	*
	100	* Use "unsigned long" accesses to let user-mode fd_set's be long-aligned.
	101	*/
	102	static inline
	103	int get_fd_set(unsigned long nr, void __user ufdset, unsigned long fdset)
	104	{
	105	nr = FDS_BYTES(nr);
	106	if (ufdset)
	107	return copy_from_user(fdset, ufdset, nr) ? -EFAULT : 0;
	108
	109	memset(fdset, 0, nr);
	110	return 0;
	111	}
	112
	113	static inline unsigned long __must_check
	114	set_fd_set(unsigned long nr, void __user ufdset, unsigned long fdset)
	115	{
	116	if (ufdset)
	117	return __copy_to_user(ufdset, fdset, FDS_BYTES(nr));
	118	return 0;
	119	}
	120
	121	static inline
	122	void zero_fd_set(unsigned long nr, unsigned long *fdset)
	123	{
	124	memset(fdset, 0, FDS_BYTES(nr));
	125	}
	126
9f72949f DW	127	#define MAX_INT64_SECONDS (((s64)(~((u64)0)>>1)/HZ)-1)
9f72949f DW	128
8ff3e8e8	129	extern int do_select(int n, fd_set_bits fds, struct timespec end_time);
9f72949f	130	extern int do_sys_poll(struct pollfd __user * ufds, unsigned int nfds,
8ff3e8e8	131	struct timespec *end_time);
a2dcb44c	132	extern int core_sys_select(int n, fd_set __user inp, fd_set __user outp,
8ff3e8e8	133	fd_set __user exp, struct timespec end_time);
1da177e4	134
b773ad40 TG	135	extern int poll_select_set_timeout(struct timespec *to, long sec, long nsec);
b773ad40 TG	136
1da177e4 LT	137	#endif /* KERNEL */
	138
	139	#endif /* _LINUX_POLL_H */