#ifndef __LINUX__AIO_H
#define __LINUX__AIO_H
#include <linux/list.h>
#include <linux/workqueue.h>
#include <linux/aio_abi.h>
#include <asm/atomic.h>
#define AIO_MAXSEGS 4
#define AIO_KIOGRP_NR_ATOMIC 8
struct kioctx;
/* Notes on cancelling a kiocb:
* If a kiocb is cancelled, aio_complete may return 0 to indicate
* that cancel has not yet disposed of the kiocb. All cancel
* operations *must* call aio_put_req to dispose of the kiocb
* to guard against races with the completion code.
*/
#define KIOCB_C_CANCELLED 0x01
#define KIOCB_C_COMPLETE 0x02
#define KIOCB_SYNC_KEY (~0U)
/* ki_flags bits */
#define KIF_LOCKED 0
#define KIF_KICKED 1
#define KIF_CANCELLED 2
#define kiocbTryLock(iocb) test_and_set_bit(KIF_LOCKED, &(iocb)->ki_flags)
#define kiocbTryKick(iocb) test_and_set_bit(KIF_KICKED, &(iocb)->ki_flags)
#define kiocbSetLocked(iocb) set_bit(KIF_LOCKED, &(iocb)->ki_flags)
#define kiocbSetKicked(iocb) set_bit(KIF_KICKED, &(iocb)->ki_flags)
#define kiocbSetCancelled(iocb) set_bit(KIF_CANCELLED, &(iocb)->ki_flags)
#define kiocbClearLocked(iocb) clear_bit(KIF_LOCKED, &(iocb)->ki_flags)
#define kiocbClearKicked(iocb) clear_bit(KIF_KICKED, &(iocb)->ki_flags)
#define kiocbClearCancelled(iocb) clear_bit(KIF_CANCELLED, &(iocb)->ki_flags)
#define kiocbIsLocked(iocb) test_bit(KIF_LOCKED, &(iocb)->ki_flags)
#define kiocbIsKicked(iocb) test_bit(KIF_KICKED, &(iocb)->ki_flags)
#define kiocbIsCancelled(iocb) test_bit(KIF_CANCELLED, &(iocb)->ki_flags)
struct kiocb {
struct list_head ki_run_list;
long ki_flags;
int ki_users;
unsigned ki_key; /* id of this request */
struct file *ki_filp;
struct kioctx *ki_ctx; /* may be NULL for sync ops */
int (*ki_cancel)(struct kiocb *, struct io_event *);
ssize_t (*ki_retry)(struct kiocb *);
void (*ki_dtor)(struct kiocb *);
struct list_head ki_list; /* the aio core uses this
* for cancellation */
union {
void __user *user;
struct task_struct *tsk;
} ki_obj;
__u64 ki_user_data; /* user's data for completion */
loff_t ki_pos;
/* State that we remember to be able to restart/retry */
unsigned short ki_opcode;
size_t ki_nbytes; /* copy of iocb->aio_nbytes */
char __user *ki_buf; /* remaining iocb->aio_buf */
size_t ki_left; /* remaining bytes */
wait_queue_t ki_wait;
long ki_retried; /* just for testing */
long ki_kicked; /* just for testing */
long ki_queued; /* just for testing */
void *private;
};
#define is_sync_kiocb(iocb) ((iocb)->ki_key == KIOCB_SYNC_KEY)
#define init_sync_kiocb(x, filp) \
do { \
struct task_struct *tsk = current; \
(x)->ki_flags = 0; \
(x)->ki_users = 1; \
(x)->ki_key = KIOCB_SYNC_KEY; \
(x)->ki_filp = (filp); \
(x)->ki_ctx = &tsk->active_mm->default_kioctx; \
(x)->ki_cancel = NULL; \
(x)->ki_dtor = NULL; \
(x)->ki_obj.tsk = tsk; \
(x)->ki_user_data = 0; \
init_wait((&(x)->ki_wait)); \
} while (0)
#define AIO_RING_MAGIC 0xa10a10a1
#define AIO_RING_COMPAT_FEATURES 1
#define AIO_RING_INCOMPAT_FEATURES 0
struct aio_ring {
unsigned id; /* kernel internal index number */
unsigned nr; /* number of io_events */
unsigned head;
unsigned tail;
unsigned magic;
unsigned compat_features;
unsigned incompat_features;
unsigned header_length; /* size of aio_ring */
struct io_event io_events[0];
}; /* 128 bytes + ring size */
#define aio_ring_avail(info, ring) (((ring)->head + (info)->nr - 1 - (ring)->tail) % (info)->nr)
#define AIO_RING_PAGES 8
struct aio_ring_info {
unsigned long mmap_base;
unsigned long mmap_size;
struct page **ring_pages;
spinlock_t ring_lock;
long nr_pages;
unsigned nr, tail;
struct page *internal_pages[AIO_RING_PAGES];
};
struct kioctx {
atomic_t users;
int dead;
struct mm_struct *mm;
/* This needs improving */
unsigned long user_id;
struct kioctx *next;
wait_queue_head_t wait;
spinlock_t ctx_lock;
int reqs_active;
struct list_head active_reqs; /* used for cancellation */
struct list_head run_list; /* used for kicked reqs */
unsigned max_reqs;
struct aio_ring_info ring_info;
struct work_struct wq;
};
/* prototypes */
extern unsigned aio_max_size;
extern ssize_t FASTCALL(wait_on_sync_kiocb(struct kiocb *iocb));
extern int FASTCALL(aio_put_req(struct kiocb *iocb));
extern void FASTCALL(kick_iocb(struct kiocb *iocb));
extern int FASTCALL(aio_complete(struct kiocb *iocb, long res, long res2));
extern void FASTCALL(__put_ioctx(struct kioctx *ctx));
struct mm_struct;
extern void FASTCALL(exit_aio(struct mm_struct *mm));
extern struct kioctx *lookup_ioctx(unsigned long ctx_id);
extern int FASTCALL(io_submit_one(struct kioctx *ctx,
struct iocb __user *user_iocb, struct iocb *iocb));
/* semi private, but used by the 32bit emulations: */
struct kioctx *lookup_ioctx(unsigned long ctx_id);
int FASTCALL(io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb,
struct iocb *iocb));
#define get_ioctx(kioctx) do { if (unlikely(atomic_read(&(kioctx)->users) <= 0)) BUG(); atomic_inc(&(kioctx)->users); } while (0)
#define put_ioctx(kioctx) do { if (unlikely(atomic_dec_and_test(&(kioctx)->users))) __put_ioctx(kioctx); else if (unlikely(atomic_read(&(kioctx)->users) < 0)) BUG(); } while (0)
#define in_aio() !is_sync_wait(current->io_wait)
/* may be used for debugging */
#define warn_if_async() \
do { \
if (in_aio()) { \
printk(KERN_ERR "%s(%s:%d) called in async context!\n", \
__FUNCTION__, __FILE__, __LINE__); \
dump_stack(); \
} \
} while (0)
#define io_wait_to_kiocb(wait) container_of(wait, struct kiocb, ki_wait)
#define is_retried_kiocb(iocb) ((iocb)->ki_retried > 1)
#include <linux/aio_abi.h>
static inline struct kiocb *list_kiocb(struct list_head *h)
{
return list_entry(h, struct kiocb, ki_list);
}
/* for sysctl: */
extern atomic_t aio_nr;
extern unsigned aio_max_nr;
#endif /* __LINUX__AIO_H */
