#include <linux/list.h>
#include <linux/workqueue.h>
#include <linux/aio_abi.h>
+#include <linux/uio.h>
#include <asm/atomic.h>
+#include <linux/uio.h>
#define AIO_MAXSEGS 4
#define AIO_KIOGRP_NR_ATOMIC 8
#define KIOCB_SYNC_KEY (~0U)
-#define KIOCB_PRIVATE_SIZE (24 * sizeof(long))
-
/* ki_flags bits */
-#define KIF_LOCKED 0
+/*
+ * This may be used for cancel/retry serialization in the future, but
+ * for now it's unused and we probably don't want modules to even
+ * think they can use it.
+ */
+/* #define KIF_LOCKED 0 */
#define KIF_KICKED 1
#define KIF_CANCELLED 2
#define kiocbIsKicked(iocb) test_bit(KIF_KICKED, &(iocb)->ki_flags)
#define kiocbIsCancelled(iocb) test_bit(KIF_CANCELLED, &(iocb)->ki_flags)
+/* is there a better place to document function pointer methods? */
+/**
+ * ki_retry - iocb forward progress callback
+ * @kiocb: The kiocb struct to advance by performing an operation.
+ *
+ * This callback is called when the AIO core wants a given AIO operation
+ * to make forward progress. The kiocb argument describes the operation
+ * that is to be performed. As the operation proceeds, perhaps partially,
+ * ki_retry is expected to update the kiocb with progress made. Typically
+ * ki_retry is set in the AIO core and it itself calls file_operations
+ * helpers.
+ *
+ * ki_retry's return value determines when the AIO operation is completed
+ * and an event is generated in the AIO event ring. Except the special
+ * return values described below, the value that is returned from ki_retry
+ * is transferred directly into the completion ring as the operation's
+ * resulting status. Once this has happened ki_retry *MUST NOT* reference
+ * the kiocb pointer again.
+ *
+ * If ki_retry returns -EIOCBQUEUED it has made a promise that aio_complete()
+ * will be called on the kiocb pointer in the future. The AIO core will
+ * not ask the method again -- ki_retry must ensure forward progress.
+ * aio_complete() must be called once and only once in the future, multiple
+ * calls may result in undefined behaviour.
+ *
+ * If ki_retry returns -EIOCBRETRY it has made a promise that kick_iocb()
+ * will be called on the kiocb pointer in the future. This may happen
+ * through generic helpers that associate kiocb->ki_wait with a wait
+ * queue head that ki_retry uses via current->io_wait. It can also happen
+ * with custom tracking and manual calls to kick_iocb(), though that is
+ * discouraged. In either case, kick_iocb() must be called once and only
+ * once. ki_retry must ensure forward progress, the AIO core will wait
+ * indefinitely for kick_iocb() to be called.
+ */
struct kiocb {
struct list_head ki_run_list;
long ki_flags;
struct file *ki_filp;
struct kioctx *ki_ctx; /* may be NULL for sync ops */
int (*ki_cancel)(struct kiocb *, struct io_event *);
- long (*ki_retry)(struct kiocb *);
-
- struct list_head ki_list; /* the aio core uses this
- * for cancellation */
+ ssize_t (*ki_retry)(struct kiocb *);
+ void (*ki_dtor)(struct kiocb *);
union {
void __user *user;
struct task_struct *tsk;
} ki_obj;
+
__u64 ki_user_data; /* user's data for completion */
+ wait_queue_t ki_wait;
loff_t ki_pos;
- char private[KIOCB_PRIVATE_SIZE];
+ atomic_t ki_bio_count; /* num bio used for this iocb */
+ void *private;
+ /* 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 */
+ struct iovec ki_inline_vec; /* inline vector */
+ struct iovec *ki_iovec;
+ unsigned long ki_nr_segs;
+ unsigned long ki_cur_seg;
+
+ struct list_head ki_list; /* the aio core uses this
+ * for cancellation */
};
#define is_sync_kiocb(iocb) ((iocb)->ki_key == KIOCB_SYNC_KEY)
(x)->ki_users = 1; \
(x)->ki_key = KIOCB_SYNC_KEY; \
(x)->ki_filp = (filp); \
- (x)->ki_ctx = &tsk->active_mm->default_kioctx; \
+ (x)->ki_ctx = NULL; \
(x)->ki_cancel = NULL; \
+ (x)->ki_retry = 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
struct list_head active_reqs; /* used for cancellation */
struct list_head run_list; /* used for kicked reqs */
+ /* sys_io_setup currently limits this to an unsigned int */
unsigned max_reqs;
struct aio_ring_info ring_info;
- struct work_struct wq;
+ struct delayed_work wq;
};
/* prototypes */
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 get_ioctx(kioctx) do { \
+ BUG_ON(atomic_read(&(kioctx)->users) <= 0); \
+ atomic_inc(&(kioctx)->users); \
+} while (0)
+#define put_ioctx(kioctx) do { \
+ BUG_ON(atomic_read(&(kioctx)->users) <= 0); \
+ if (unlikely(atomic_dec_and_test(&(kioctx)->users))) \
+ __put_ioctx(kioctx); \
+} 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)
#include <linux/aio_abi.h>
}
/* for sysctl: */
-extern atomic_t aio_nr;
-extern unsigned aio_max_nr;
+extern unsigned long aio_nr;
+extern unsigned long aio_max_nr;
#endif /* __LINUX__AIO_H */
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