Merge branch 'akpm' (incoming from Andrew)

Merge more incoming from Andrew Morton:

 - Various fixes which were stalled or which I picked up recently

 - A large rotorooting of the AIO code.  Allegedly to improve
   performance but I don't really have good performance numbers (I might
   have lost the email) and I can't raise Kent today.  I held this out
   of 3.9 and we could give it another cycle if it's all too late/scary.

I ended up taking only the first two thirds of the AIO rotorooting.  I
left the percpu parts and the batch completion for later.  - Linus

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (33 commits)
  aio: don't include aio.h in sched.h
  aio: kill ki_retry
  aio: kill ki_key
  aio: give shared kioctx fields their own cachelines
  aio: kill struct aio_ring_info
  aio: kill batch allocation
  aio: change reqs_active to include unreaped completions
  aio: use cancellation list lazily
  aio: use flush_dcache_page()
  aio: make aio_read_evt() more efficient, convert to hrtimers
  wait: add wait_event_hrtimeout()
  aio: refcounting cleanup
  aio: make aio_put_req() lockless
  aio: do fget() after aio_get_req()
  aio: dprintk() -> pr_debug()
  aio: move private stuff out of aio.h
  aio: add kiocb_cancel()
  aio: kill return value of aio_complete()
  char: add aio_{read,write} to /dev/{null,zero}
  aio: remove retry-based AIO
  ...

41 files changed, 602 insertions, 1077 deletions

diff --git a/fs/9p/vfs_addr.c b/fs/9p/vfs_addr.c
index 0ad61c6a65a..055562c580b 100644
--- a/fs/9p/vfs_addr.c
+++ b/fs/9p/vfs_addr.c
@@ -33,6 +33,7 @@
 #include <linux/pagemap.h>
 #include <linux/idr.h>
 #include <linux/sched.h>
+#include <linux/aio.h>
 #include <net/9p/9p.h>
 #include <net/9p/client.h>
 
diff --git a/fs/afs/write.c b/fs/afs/write.c
index 7e03eadb40c..a890db4b989 100644
--- a/fs/afs/write.c
+++ b/fs/afs/write.c
@@ -14,6 +14,7 @@
 #include <linux/pagemap.h>
 #include <linux/writeback.h>
 #include <linux/pagevec.h>
+#include <linux/aio.h>
 #include "internal.h"
 
 static int afs_write_back_from_locked_page(struct afs_writeback *wb,
diff --git a/fs/aio.c b/fs/aio.c
index 351afe7ac78..c5b1a8c1041 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -8,6 +8,8 @@
  *
  *	See ../COPYING for licensing terms.
  */
+#define pr_fmt(fmt) "%s: " fmt, __func__
+
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/errno.h>
@@ -18,8 +20,6 @@
 #include <linux/backing-dev.h>
 #include <linux/uio.h>
 
-#define DEBUG 0
-
 #include <linux/sched.h>
 #include <linux/fs.h>
 #include <linux/file.h>
@@ -39,11 +39,76 @@
 #include <asm/kmap_types.h>
 #include <asm/uaccess.h>
 
-#if DEBUG > 1
-#define dprintk		printk
-#else
-#define dprintk(x...)	do { ; } while (0)
-#endif
+#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_PAGES	8
+
+struct kioctx {
+	atomic_t		users;
+	atomic_t		dead;
+
+	/* This needs improving */
+	unsigned long		user_id;
+	struct hlist_node	list;
+
+	/*
+	 * This is what userspace passed to io_setup(), it's not used for
+	 * anything but counting against the global max_reqs quota.
+	 *
+	 * The real limit is nr_events - 1, which will be larger (see
+	 * aio_setup_ring())
+	 */
+	unsigned		max_reqs;
+
+	/* Size of ringbuffer, in units of struct io_event */
+	unsigned		nr_events;
+
+	unsigned long		mmap_base;
+	unsigned long		mmap_size;
+
+	struct page		**ring_pages;
+	long			nr_pages;
+
+	struct rcu_head		rcu_head;
+	struct work_struct	rcu_work;
+
+	struct {
+		atomic_t	reqs_active;
+	} ____cacheline_aligned_in_smp;
+
+	struct {
+		spinlock_t	ctx_lock;
+		struct list_head active_reqs;	/* used for cancellation */
+	} ____cacheline_aligned_in_smp;
+
+	struct {
+		struct mutex	ring_lock;
+		wait_queue_head_t wait;
+	} ____cacheline_aligned_in_smp;
+
+	struct {
+		unsigned	tail;
+		spinlock_t	completion_lock;
+	} ____cacheline_aligned_in_smp;
+
+	struct page		*internal_pages[AIO_RING_PAGES];
+};
 
 /*------ sysctl variables----*/
 static DEFINE_SPINLOCK(aio_nr_lock);
@@ -54,11 +119,6 @@ unsigned long aio_max_nr = 0x10000; /* system wide maximum number of aio request
 static struct kmem_cache	*kiocb_cachep;
 static struct kmem_cache	*kioctx_cachep;
 
-static struct workqueue_struct *aio_wq;
-
-static void aio_kick_handler(struct work_struct *);
-static void aio_queue_work(struct kioctx *);
-
 /* aio_setup
  *	Creates the slab caches used by the aio routines, panic on
  *	failure as this is done early during the boot sequence.
@@ -68,10 +128,7 @@ static int __init aio_setup(void)
 	kiocb_cachep = KMEM_CACHE(kiocb, SLAB_HWCACHE_ALIGN|SLAB_PANIC);
 	kioctx_cachep = KMEM_CACHE(kioctx,SLAB_HWCACHE_ALIGN|SLAB_PANIC);
 
-	aio_wq = alloc_workqueue("aio", 0, 1);	/* used to limit concurrency */
-	BUG_ON(!aio_wq);
-
-	pr_debug("aio_setup: sizeof(struct page) = %d\n", (int)sizeof(struct page));
+	pr_debug("sizeof(struct page) = %zu\n", sizeof(struct page));
 
 	return 0;
 }
@@ -79,28 +136,23 @@ __initcall(aio_setup);
 
 static void aio_free_ring(struct kioctx *ctx)
 {
-	struct aio_ring_info *info = &ctx->ring_info;
 	long i;
 
-	for (i=0; i<info->nr_pages; i++)
-		put_page(info->ring_pages[i]);
+	for (i = 0; i < ctx->nr_pages; i++)
+		put_page(ctx->ring_pages[i]);
 
-	if (info->mmap_size) {
-		BUG_ON(ctx->mm != current->mm);
-		vm_munmap(info->mmap_base, info->mmap_size);
-	}
+	if (ctx->mmap_size)
+		vm_munmap(ctx->mmap_base, ctx->mmap_size);
 
-	if (info->ring_pages && info->ring_pages != info->internal_pages)
-		kfree(info->ring_pages);
-	info->ring_pages = NULL;
-	info->nr = 0;
+	if (ctx->ring_pages && ctx->ring_pages != ctx->internal_pages)
+		kfree(ctx->ring_pages);
 }
 
 static int aio_setup_ring(struct kioctx *ctx)
 {
 	struct aio_ring *ring;
-	struct aio_ring_info *info = &ctx->ring_info;
 	unsigned nr_events = ctx->max_reqs;
+	struct mm_struct *mm = current->mm;
 	unsigned long size, populate;
 	int nr_pages;
 
@@ -116,46 +168,44 @@ static int aio_setup_ring(struct kioctx *ctx)
 
 	nr_events = (PAGE_SIZE * nr_pages - sizeof(struct aio_ring)) / sizeof(struct io_event);
 
-	info->nr = 0;
-	info->ring_pages = info->internal_pages;
+	ctx->nr_events = 0;
+	ctx->ring_pages = ctx->internal_pages;
 	if (nr_pages > AIO_RING_PAGES) {
-		info->ring_pages = kcalloc(nr_pages, sizeof(struct page *), GFP_KERNEL);
-		if (!info->ring_pages)
+		ctx->ring_pages = kcalloc(nr_pages, sizeof(struct page *),
+					  GFP_KERNEL);
+		if (!ctx->ring_pages)
 			return -ENOMEM;
 	}
 
-	info->mmap_size = nr_pages * PAGE_SIZE;
-	dprintk("attempting mmap of %lu bytes\n", info->mmap_size);
-	down_write(&ctx->mm->mmap_sem);
-	info->mmap_base = do_mmap_pgoff(NULL, 0, info->mmap_size, 
-					PROT_READ|PROT_WRITE,
-					MAP_ANONYMOUS|MAP_PRIVATE, 0,
-					&populate);
-	if (IS_ERR((void *)info->mmap_base)) {
-		up_write(&ctx->mm->mmap_sem);
-		info->mmap_size = 0;
+	ctx->mmap_size = nr_pages * PAGE_SIZE;
+	pr_debug("attempting mmap of %lu bytes\n", ctx->mmap_size);
+	down_write(&mm->mmap_sem);
+	ctx->mmap_base = do_mmap_pgoff(NULL, 0, ctx->mmap_size,
+				       PROT_READ|PROT_WRITE,
+				       MAP_ANONYMOUS|MAP_PRIVATE, 0, &populate);
+	if (IS_ERR((void *)ctx->mmap_base)) {
+		up_write(&mm->mmap_sem);
+		ctx->mmap_size = 0;
 		aio_free_ring(ctx);
 		return -EAGAIN;
 	}
 
-	dprintk("mmap address: 0x%08lx\n", info->mmap_base);
-	info->nr_pages = get_user_pages(current, ctx->mm,
-					info->mmap_base, nr_pages, 
-					1, 0, info->ring_pages, NULL);
-	up_write(&ctx->mm->mmap_sem);
+	pr_debug("mmap address: 0x%08lx\n", ctx->mmap_base);
+	ctx->nr_pages = get_user_pages(current, mm, ctx->mmap_base, nr_pages,
+				       1, 0, ctx->ring_pages, NULL);
+	up_write(&mm->mmap_sem);
 
-	if (unlikely(info->nr_pages != nr_pages)) {
+	if (unlikely(ctx->nr_pages != nr_pages)) {
 		aio_free_ring(ctx);
 		return -EAGAIN;
 	}
 	if (populate)
-		mm_populate(info->mmap_base, populate);
+		mm_populate(ctx->mmap_base, populate);
 
-	ctx->user_id = info->mmap_base;
+	ctx->user_id = ctx->mmap_base;
+	ctx->nr_events = nr_events; /* trusted copy */
 
-	info->nr = nr_events;		/* trusted copy */
-
-	ring = kmap_atomic(info->ring_pages[0]);
+	ring = kmap_atomic(ctx->ring_pages[0]);
 	ring->nr = nr_events;	/* user copy */
 	ring->id = ctx->user_id;
 	ring->head = ring->tail = 0;
@@ -164,72 +214,133 @@ static int aio_setup_ring(struct kioctx *ctx)
 	ring->incompat_features = AIO_RING_INCOMPAT_FEATURES;
 	ring->header_length = sizeof(struct aio_ring);
 	kunmap_atomic(ring);
+	flush_dcache_page(ctx->ring_pages[0]);
 
 	return 0;
 }
 
-
-/* aio_ring_event: returns a pointer to the event at the given index from
- * kmap_atomic().  Release the pointer with put_aio_ring_event();
- */
 #define AIO_EVENTS_PER_PAGE	(PAGE_SIZE / sizeof(struct io_event))
 #define AIO_EVENTS_FIRST_PAGE	((PAGE_SIZE - sizeof(struct aio_ring)) / sizeof(struct io_event))
 #define AIO_EVENTS_OFFSET	(AIO_EVENTS_PER_PAGE - AIO_EVENTS_FIRST_PAGE)
 
-#define aio_ring_event(info, nr) ({					\
-	unsigned pos = (nr) + AIO_EVENTS_OFFSET;			\
-	struct io_event *__event;					\
-	__event = kmap_atomic(						\
-			(info)->ring_pages[pos / AIO_EVENTS_PER_PAGE]); \
-	__event += pos % AIO_EVENTS_PER_PAGE;				\
-	__event;							\
-})
-
-#define put_aio_ring_event(event) do {		\
-	struct io_event *__event = (event);	\
-	(void)__event;				\
-	kunmap_atomic((void *)((unsigned long)__event & PAGE_MASK)); \
-} while(0)
-
-static void ctx_rcu_free(struct rcu_head *head)
+void kiocb_set_cancel_fn(struct kiocb *req, kiocb_cancel_fn *cancel)
+{
+	struct kioctx *ctx = req->ki_ctx;
+	unsigned long flags;
+
+	spin_lock_irqsave(&ctx->ctx_lock, flags);
+
+	if (!req->ki_list.next)
+		list_add(&req->ki_list, &ctx->active_reqs);
+
+	req->ki_cancel = cancel;
+
+	spin_unlock_irqrestore(&ctx->ctx_lock, flags);
+}
+EXPORT_SYMBOL(kiocb_set_cancel_fn);
+
+static int kiocb_cancel(struct kioctx *ctx, struct kiocb *kiocb,
+			struct io_event *res)
+{
+	kiocb_cancel_fn *old, *cancel;
+	int ret = -EINVAL;
+
+	/*
+	 * Don't want to set kiocb->ki_cancel = KIOCB_CANCELLED unless it
+	 * actually has a cancel function, hence the cmpxchg()
+	 */
+
+	cancel = ACCESS_ONCE(kiocb->ki_cancel);
+	do {
+		if (!cancel || cancel == KIOCB_CANCELLED)
+			return ret;
+
+		old = cancel;
+		cancel = cmpxchg(&kiocb->ki_cancel, old, KIOCB_CANCELLED);
+	} while (cancel != old);
+
+	atomic_inc(&kiocb->ki_users);
+	spin_unlock_irq(&ctx->ctx_lock);
+
+	memset(res, 0, sizeof(*res));
+	res->obj = (u64)(unsigned long)kiocb->ki_obj.user;
+	res->data = kiocb->ki_user_data;
+	ret = cancel(kiocb, res);
+
+	spin_lock_irq(&ctx->ctx_lock);
+
+	return ret;
+}
+
+static void free_ioctx_rcu(struct rcu_head *head)
 {
 	struct kioctx *ctx = container_of(head, struct kioctx, rcu_head);
 	kmem_cache_free(kioctx_cachep, ctx);
 }
 
-/* __put_ioctx
- *	Called when the last user of an aio context has gone away,
- *	and the struct needs to be freed.
+/*
+ * When this function runs, the kioctx has been removed from the "hash table"
+ * and ctx->users has dropped to 0, so we know no more kiocbs can be submitted -
+ * now it's safe to cancel any that need to be.
  */
-static void __put_ioctx(struct kioctx *ctx)
+static void free_ioctx(struct kioctx *ctx)
 {
-	unsigned nr_events = ctx->max_reqs;
-	BUG_ON(ctx->reqs_active);
+	struct aio_ring *ring;
+	struct io_event res;
+	struct kiocb *req;
+	unsigned head, avail;
 
-	cancel_delayed_work_sync(&ctx->wq);
-	aio_free_ring(ctx);
-	mmdrop(ctx->mm);
-	ctx->mm = NULL;
-	if (nr_events) {
-		spin_lock(&aio_nr_lock);
-		BUG_ON(aio_nr - nr_events > aio_nr);
-		aio_nr -= nr_events;
-		spin_unlock(&aio_nr_lock);
+	spin_lock_irq(&ctx->ctx_lock);
+
+	while (!list_empty(&ctx->active_reqs)) {
+		req = list_first_entry(&ctx->active_reqs,
+				       struct kiocb, ki_list);
+
+		list_del_init(&req->ki_list);
+		kiocb_cancel(ctx, req, &res);
 	}
-	pr_debug("__put_ioctx: freeing %p\n", ctx);
-	call_rcu(&ctx->rcu_head, ctx_rcu_free);
-}
 
-static inline int try_get_ioctx(struct kioctx *kioctx)
-{
-	return atomic_inc_not_zero(&kioctx->users);
+	spin_unlock_irq(&ctx->ctx_lock);
+
+	ring = kmap_atomic(ctx->ring_pages[0]);
+	head = ring->head;
+	kunmap_atomic(ring);
+
+	while (atomic_read(&ctx->reqs_active) > 0) {
+		wait_event(ctx->wait, head != ctx->tail);
+
+		avail = (head <= ctx->tail ? ctx->tail : ctx->nr_events) - head;
+
+		atomic_sub(avail, &ctx->reqs_active);
+		head += avail;
+		head %= ctx->nr_events;
+	}
+
+	WARN_ON(atomic_read(&ctx->reqs_active) < 0);
+
+	aio_free_ring(ctx);
+
+	spin_lock(&aio_nr_lock);
+	BUG_ON(aio_nr - ctx->max_reqs > aio_nr);
+	aio_nr -= ctx->max_reqs;
+	spin_unlock(&aio_nr_lock);
+
+	pr_debug("freeing %p\n", ctx);
+
+	/*
+	 * Here the call_rcu() is between the wait_event() for reqs_active to
+	 * hit 0, and freeing the ioctx.
+	 *
+	 * aio_complete() decrements reqs_active, but it has to touch the ioctx
+	 * after to issue a wakeup so we use rcu.
+	 */
+	call_rcu(&ctx->rcu_head, free_ioctx_rcu);
 }
 
-static inline void put_ioctx(struct kioctx *kioctx)
+static void put_ioctx(struct kioctx *ctx)
 {
-	BUG_ON(atomic_read(&kioctx->users) <= 0);
-	if (unlikely(atomic_dec_and_test(&kioctx->users)))
-		__put_ioctx(kioctx);
+	if (unlikely(atomic_dec_and_test(&ctx->users)))
+		free_ioctx(ctx);
 }
 
 /* ioctx_alloc
@@ -237,7 +348,7 @@ static inline void put_ioctx(struct kioctx *kioctx)
  */
 static struct kioctx *ioctx_alloc(unsigned nr_events)
 {
-	struct mm_struct *mm;
+	struct mm_struct *mm = current->mm;
 	struct kioctx *ctx;
 	int err = -ENOMEM;
 
@@ -256,17 +367,15 @@ static struct kioctx *ioctx_alloc(unsigned nr_events)
 		return ERR_PTR(-ENOMEM);
 
 	ctx->max_reqs = nr_events;
-	mm = ctx->mm = current->mm;
-	atomic_inc(&mm->mm_count);
 
 	atomic_set(&ctx->users, 2);
+	atomic_set(&ctx->dead, 0);
 	spin_lock_init(&ctx->ctx_lock);
-	spin_lock_init(&ctx->ring_info.ring_lock);
+	spin_lock_init(&ctx->completion_lock);
+	mutex_init(&ctx->ring_lock);
 	init_waitqueue_head(&ctx->wait);
 
 	INIT_LIST_HEAD(&ctx->active_reqs);
-	INIT_LIST_HEAD(&ctx->run_list);
-	INIT_DELAYED_WORK(&ctx->wq, aio_kick_handler);
 
 	if (aio_setup_ring(ctx) < 0)
 		goto out_freectx;
@@ -286,64 +395,56 @@ static struct kioctx *ioctx_alloc(unsigned nr_events)
 	hlist_add_head_rcu(&ctx->list, &mm->ioctx_list);
 	spin_unlock(&mm->ioctx_lock);
 
-	dprintk("aio: allocated ioctx %p[%ld]: mm=%p mask=0x%x\n",
-		ctx, ctx->user_id, current->mm, ctx->ring_info.nr);
+	pr_debug("allocated ioctx %p[%ld]: mm=%p mask=0x%x\n",
+		 ctx, ctx->user_id, mm, ctx->nr_events);
 	return ctx;
 
 out_cleanup:
 	err = -EAGAIN;
 	aio_free_ring(ctx);
 out_freectx:
-	mmdrop(mm);
 	kmem_cache_free(kioctx_cachep, ctx);
-	dprintk("aio: error allocating ioctx %d\n", err);
+	pr_debug("error allocating ioctx %d\n", err);
 	return ERR_PTR(err);
 }
 
-/* kill_ctx
- *	Cancels all outstanding aio requests on an aio context.  Used 
- *	when the processes owning a context have all exited to encourage 
- *	the rapid destruction of the kioctx.
- */
-static void kill_ctx(struct kioctx *ctx)
+static void kill_ioctx_work(struct work_struct *work)
 {
-	int (*cancel)(struct kiocb *, struct io_event *);
-	struct task_struct *tsk = current;
-	DECLARE_WAITQUEUE(wait, tsk);
-	struct io_event res;
+	struct kioctx *ctx = container_of(work, struct kioctx, rcu_work);
 
-	spin_lock_irq(&ctx->ctx_lock);
-	ctx->dead = 1;
-	while (!list_empty(&ctx->active_reqs)) {
-		struct list_head *pos = ctx->active_reqs.next;
-		struct kiocb *iocb = list_kiocb(pos);
-		list_del_init(&iocb->ki_list);
-		cancel = iocb->ki_cancel;
-		kiocbSetCancelled(iocb);
-		if (cancel) {
-			iocb->ki_users++;
-			spin_unlock_irq(&ctx->ctx_lock);
-			cancel(iocb, &res);
-			spin_lock_irq(&ctx->ctx_lock);
-		}
-	}
+	wake_up_all(&ctx->wait);
+	put_ioctx(ctx);
+}
 
-	if (!ctx->reqs_active)
-		goto out;
+static void kill_ioctx_rcu(struct rcu_head *head)
+{
+	struct kioctx *ctx = container_of(head, struct kioctx, rcu_head);
 
-	add_wait_queue(&ctx->wait, &wait);
-	set_task_state(tsk, TASK_UNINTERRUPTIBLE);
-	while (ctx->reqs_active) {
-		spin_unlock_irq(&ctx->ctx_lock);
-		io_schedule();
-		set_task_state(tsk, TASK_UNINTERRUPTIBLE);
-		spin_lock_irq(&ctx->ctx_lock);
-	}
-	__set_task_state(tsk, TASK_RUNNING);
-	remove_wait_queue(&ctx->wait, &wait);
+	INIT_WORK(&ctx->rcu_work, kill_ioctx_work);
+	schedule_work(&ctx->rcu_work);
+}
 
-out:
-	spin_unlock_irq(&ctx->ctx_lock);
+/* kill_ioctx
+ *	Cancels all outstanding aio requests on an aio context.  Used
+ *	when the processes owning a context have all exited to encourage
+ *	the rapid destruction of the kioctx.
+ */
+static void kill_ioctx(struct kioctx *ctx)
+{
+	if (!atomic_xchg(&ctx->dead, 1)) {
+		hlist_del_rcu(&ctx->list);
+		/* Between hlist_del_rcu() and dropping the initial ref */
+		synchronize_rcu();
+
+		/*
+		 * We can't punt to workqueue here because put_ioctx() ->
+		 * free_ioctx() will unmap the ringbuffer, and that has to be
+		 * done in the original process's context. kill_ioctx_rcu/work()
+		 * exist for exit_aio(), as in that path free_ioctx() won't do
+		 * the unmap.
+		 */
+		kill_ioctx_work(&ctx->rcu_work);
+	}
 }
 
 /* wait_on_sync_kiocb:
@@ -351,9 +452,9 @@ out:
  */
 ssize_t wait_on_sync_kiocb(struct kiocb *iocb)
 {
-	while (iocb->ki_users) {
+	while (atomic_read(&iocb->ki_users)) {
 		set_current_state(TASK_UNINTERRUPTIBLE);
-		if (!iocb->ki_users)
+		if (!atomic_read(&iocb->ki_users))
 			break;
 		io_schedule();
 	}
@@ -362,28 +463,26 @@ ssize_t wait_on_sync_kiocb(struct kiocb *iocb)
 }
 EXPORT_SYMBOL(wait_on_sync_kiocb);
 
-/* exit_aio: called when the last user of mm goes away.  At this point, 
- * there is no way for any new requests to be submited or any of the 
- * io_* syscalls to be called on the context.  However, there may be 
- * outstanding requests which hold references to the context; as they 
- * go away, they will call put_ioctx and release any pinned memory
- * associated with the request (held via struct page * references).
+/*
+ * exit_aio: called when the last user of mm goes away.  At this point, there is
+ * no way for any new requests to be submited or any of the io_* syscalls to be
+ * called on the context.
+ *
+ * There may be outstanding kiocbs, but free_ioctx() will explicitly wait on
+ * them.
  */
 void exit_aio(struct mm_struct *mm)
 {
 	struct kioctx *ctx;
+	struct hlist_node *n;
 
-	while (!hlist_empty(&mm->ioctx_list)) {
-		ctx = hlist_entry(mm->ioctx_list.first, struct kioctx, list);
-		hlist_del_rcu(&ctx->list);
-
-		kill_ctx(ctx);
-
+	hlist_for_each_entry_safe(ctx, n, &mm->ioctx_list, list) {
 		if (1 != atomic_read(&ctx->users))
 			printk(KERN_DEBUG
 				"exit_aio:ioctx still alive: %d %d %d\n",
-				atomic_read(&ctx->users), ctx->dead,
-				ctx->reqs_active);
+				atomic_read(&ctx->users),
+				atomic_read(&ctx->dead),
+				atomic_read(&ctx->reqs_active));
 		/*
 		 * We don't need to bother with munmap() here -
 		 * exit_mmap(mm) is coming and it'll unmap everything.
@@ -391,150 +490,53 @@ void exit_aio(struct mm_struct *mm)
 		 * as indicator that it needs to unmap the area,
 		 * just set it to 0; aio_free_ring() is the only
 		 * place that uses ->mmap_size, so it's safe.
-		 * That way we get all munmap done to current->mm -
-		 * all other callers have ctx->mm == current->mm.
 		 */
-		ctx->ring_info.mmap_size = 0;
-		put_ioctx(ctx);
+		ctx->mmap_size = 0;
+
+		if (!atomic_xchg(&ctx->dead, 1)) {
+			hlist_del_rcu(&ctx->list);
+			call_rcu(&ctx->rcu_head, kill_ioctx_rcu);
+		}
 	}
 }
 
 /* aio_get_req
- *	Allocate a slot for an aio request.  Increments the users count
+ *	Allocate a slot for an aio request.  Increments the ki_users count
  * of the kioctx so that the kioctx stays around until all requests are
  * complete.  Returns NULL if no requests are free.
  *
- * Returns with kiocb->users set to 2.  The io submit code path holds
+ * Returns with kiocb->ki_users set to 2.  The io submit code path holds
  * an extra reference while submitting the i/o.
  * This prevents races between the aio code path referencing the
  * req (after submitting it) and aio_complete() freeing the req.
  */
-static struct kiocb *__aio_get_req(struct kioctx *ctx)
+static inline struct kiocb *aio_get_req(struct kioctx *ctx)
 {
-	struct kiocb *req = NULL;
+	struct kiocb *req;
 
-	req = kmem_cache_alloc(kiocb_cachep, GFP_KERNEL);
-	if (unlikely(!req))
+	if (atomic_read(&ctx->reqs_active) >= ctx->nr_events)
 		return NULL;
 
-	req->ki_flags = 0;
-	req->ki_users = 2;
-	req->ki_key = 0;
-	req->ki_ctx = ctx;
-	req->ki_cancel = NULL;
-	req->ki_retry = NULL;
-	req->ki_dtor = NULL;
-	req->private = NULL;
-	req->ki_iovec = NULL;
-	INIT_LIST_HEAD(&req->ki_run_list);
-	req->ki_eventfd = NULL;
-
-	return req;
-}
-
-/*
- * struct kiocb's are allocated in batches to reduce the number of
- * times the ctx lock is acquired and released.
- */
-#define KIOCB_BATCH_SIZE	32L
-struct kiocb_batch {
-	struct list_head head;
-	long count; /* number of requests left to allocate */
-};
-
-static void kiocb_batch_init(struct kiocb_batch *batch, long total)
-{
-	INIT_LIST_HEAD(&batch->head);
-	batch->count = total;
-}
-
-static void kiocb_batch_free(struct kioctx *ctx, struct kiocb_batch *batch)
-{
-	struct kiocb *req, *n;
-
-	if (list_empty(&batch->head))
-		return;
-
-	spin_lock_irq(&ctx->ctx_lock);
-	list_for_each_entry_safe(req, n, &batch->head, ki_batch) {
-		list_del(&req->ki_batch);
-		list_del(&req->ki_list);
-		kmem_cache_free(kiocb_cachep, req);
-		ctx->reqs_active--;
-	}
-	if (unlikely(!ctx->reqs_active && ctx->dead))
-		wake_up_all(&ctx->wait);
-	spin_unlock_irq(&ctx->ctx_lock);
-}
-
-/*
- * Allocate a batch of kiocbs.  This avoids taking and dropping the
- * context lock a lot during setup.
- */
-static int kiocb_batch_refill(struct kioctx *ctx, struct kiocb_batch *batch)
-{
-	unsigned short allocated, to_alloc;
-	long avail;
-	struct kiocb *req, *n;
-	struct aio_ring *ring;
-
-	to_alloc = min(batch->count, KIOCB_BATCH_SIZE);
-	for (allocated = 0; allocated < to_alloc; allocated++) {
-		req = __aio_get_req(ctx);
-		if (!req)
-			/* allocation failed, go with what we've got */
-			break;
-		list_add(&req->ki_batch, &batch->head);
-	}
-
-	if (allocated == 0)
-		goto out;
-
-	spin_lock_irq(&ctx->ctx_lock);
-	ring = kmap_atomic(ctx->ring_info.ring_pages[0]);
-
-	avail = aio_ring_avail(&ctx->ring_info, ring) - ctx->reqs_active;
-	BUG_ON(avail < 0);
-	if (avail < allocated) {
-		/* Trim back the number of requests. */
-		list_for_each_entry_safe(req, n, &batch->head, ki_batch) {
-			list_del(&req->ki_batch);
-			kmem_cache_free(kiocb_cachep, req);
-			if (--allocated <= avail)
-				break;
-		}
-	}
-
-	batch->count -= allocated;
-	list_for_each_entry(req, &batch->head, ki_batch) {
-		list_add(&req->ki_list, &ctx->active_reqs);
-		ctx->reqs_active++;
-	}
+	if (atomic_inc_return(&ctx->reqs_active) > ctx->nr_events - 1)
+		goto out_put;
 
-	kunmap_atomic(ring);
-	spin_unlock_irq(&ctx->ctx_lock);
-
-out:
-	return allocated;
-}
+	req = kmem_cache_alloc(kiocb_cachep, GFP_KERNEL|__GFP_ZERO);
+	if (unlikely(!req))
+		goto out_put;
 
-static inline struct kiocb *aio_get_req(struct kioctx *ctx,
-					struct kiocb_batch *batch)
-{
-	struct kiocb *req;
+	atomic_set(&req->ki_users, 2);
+	req->ki_ctx = ctx;
 
-	if (list_empty(&batch->head))
-		if (kiocb_batch_refill(ctx, batch) == 0)
-			return NULL;
-	req = list_first_entry(&batch->head, struct kiocb, ki_batch);
-	list_del(&req->ki_batch);
 	return req;
+out_put:
+	atomic_dec(&ctx->reqs_active);
+	return NULL;
 }
 
-static inline void really_put_req(struct kioctx *ctx, struct kiocb *req)
+static void kiocb_free(struct kiocb *req)
 {
-	assert_spin_locked(&ctx->ctx_lock);
-
+	if (req->ki_filp)
+		fput(req->ki_filp);
 	if (req->ki_eventfd != NULL)
 		eventfd_ctx_put(req->ki_eventfd);
 	if (req->ki_dtor)
@@ -542,48 +544,12 @@ static inline void really_put_req(struct kioctx *ctx, struct kiocb *req)
 	if (req->ki_iovec != &req->ki_inline_vec)
 		kfree(req->ki_iovec);
 	kmem_cache_free(kiocb_cachep, req);
-	ctx->reqs_active--;
-
-	if (unlikely(!ctx->reqs_active && ctx->dead))
-		wake_up_all(&ctx->wait);
 }
 
-/* __aio_put_req
- *	Returns true if this put was the last user of the request.
- */
-static int __aio_put_req(struct kioctx *ctx, struct kiocb *req)
+void aio_put_req(struct kiocb *req)
 {
-	dprintk(KERN_DEBUG "aio_put(%p): f_count=%ld\n",
-		req, atomic_long_read(&req->ki_filp->f_count));
-
-	assert_spin_locked(&ctx->ctx_lock);
-
-	req->ki_users--;
-	BUG_ON(req->ki_users < 0);
-	if (likely(req->ki_users))
-		return 0;
-	list_del(&req->ki_list);		/* remove from active_reqs */
-	req->ki_cancel = NULL;
-	req->ki_retry = NULL;
-
-	fput(req->ki_filp);
-	req->ki_filp = NULL;
-	really_put_req(ctx, req);
-	return 1;
-}
-
-/* aio_put_req
- *	Returns true if this put was the last user of the kiocb,
- *	false if the request is still in use.
- */
-int aio_put_req(struct kiocb *req)
-{
-	struct kioctx *ctx = req->ki_ctx;
-	int ret;
-	spin_lock_irq(&ctx->ctx_lock);
-	ret = __aio_put_req(ctx, req);
-	spin_unlock_irq(&ctx->ctx_lock);
-	return ret;
+	if (atomic_dec_and_test(&req->ki_users))
+		kiocb_free(req);
 }
 EXPORT_SYMBOL(aio_put_req);
 
@@ -595,13 +561,8 @@ static struct kioctx *lookup_ioctx(unsigned long ctx_id)
 	rcu_read_lock();
 
 	hlist_for_each_entry_rcu(ctx, &mm->ioctx_list, list) {
-		/*
-		 * RCU protects us against accessing freed memory but
-		 * we have to be careful not to get a reference when the
-		 * reference count already dropped to 0 (ctx->dead test
-		 * is unreliable because of races).
-		 */
-		if (ctx->user_id == ctx_id && !ctx->dead && try_get_ioctx(ctx)){
+		if (ctx->user_id == ctx_id) {
+			atomic_inc(&ctx->users);
 			ret = ctx;
 			break;
 		}
@@ -611,295 +572,16 @@ static struct kioctx *lookup_ioctx(unsigned long ctx_id)
 	return ret;
 }
 
-/*
- * Queue up a kiocb to be retried. Assumes that the kiocb
- * has already been marked as kicked, and places it on
- * the retry run list for the corresponding ioctx, if it
- * isn't already queued. Returns 1 if it actually queued
- * the kiocb (to tell the caller to activate the work
- * queue to process it), or 0, if it found that it was
- * already queued.
- */
-static inline int __queue_kicked_iocb(struct kiocb *iocb)
-{
-	struct kioctx *ctx = iocb->ki_ctx;
-
-	assert_spin_locked(&ctx->ctx_lock);
-
-	if (list_empty(&iocb->ki_run_list)) {
-		list_add_tail(&iocb->ki_run_list,
-			&ctx->run_list);
-		return 1;
-	}
-	return 0;
-}
-
-/* aio_run_iocb
- *	This is the core aio execution routine. It is
- *	invoked both for initial i/o submission and
- *	subsequent retries via the aio_kick_handler.
- *	Expects to be invoked with iocb->ki_ctx->lock
- *	already held. The lock is released and reacquired
- *	as needed during processing.
- *
- * Calls the iocb retry method (already setup for the
- * iocb on initial submission) for operation specific
- * handling, but takes care of most of common retry
- * execution details for a given iocb. The retry method
- * needs to be non-blocking as far as possible, to avoid
- * holding up other iocbs waiting to be serviced by the
- * retry kernel thread.
- *
- * The trickier parts in this code have to do with
- * ensuring that only one retry instance is in progress
- * for a given iocb at any time. Providing that guarantee
- * simplifies the coding of individual aio operations as
- * it avoids various potential races.
- */
-static ssize_t aio_run_iocb(struct kiocb *iocb)
-{
-	struct kioctx	*ctx = iocb->ki_ctx;
-	ssize_t (*retry)(struct kiocb *);
-	ssize_t ret;
-
-	if (!(retry = iocb->ki_retry)) {
-		printk("aio_run_iocb: iocb->ki_retry = NULL\n");
-		return 0;
-	}
-
-	/*
-	 * We don't want the next retry iteration for this
-	 * operation to start until this one has returned and
-	 * updated the iocb state. However, wait_queue functions
-	 * can trigger a kick_iocb from interrupt context in the
-	 * meantime, indicating that data is available for the next
-	 * iteration. We want to remember that and enable the
-	 * next retry iteration _after_ we are through with
-	 * this one.
-	 *
-	 * So, in order to be able to register a "kick", but
-	 * prevent it from being queued now, we clear the kick
-	 * flag, but make the kick code *think* that the iocb is
-	 * still on the run list until we are actually done.
-	 * When we are done with this iteration, we check if
-	 * the iocb was kicked in the meantime and if so, queue
-	 * it up afresh.
-	 */
-
-	kiocbClearKicked(iocb);
-
-	/*
-	 * This is so that aio_complete knows it doesn't need to
-	 * pull the iocb off the run list (We can't just call
-	 * INIT_LIST_HEAD because we don't want a kick_iocb to
-	 * queue this on the run list yet)
-	 */
-	iocb->ki_run_list.next = iocb->ki_run_list.prev = NULL;
-	spin_unlock_irq(&ctx->ctx_lock);
-
-	/* Quit retrying if the i/o has been cancelled */
-	if (kiocbIsCancelled(iocb)) {
-		ret = -EINTR;
-		aio_complete(iocb, ret, 0);
-		/* must not access the iocb after this */
-		goto out;
-	}
-
-	/*
-	 * Now we are all set to call the retry method in async
-	 * context.
-	 */
-	ret = retry(iocb);
-
-	if (ret != -EIOCBRETRY && ret != -EIOCBQUEUED) {
-		/*
-		 * There's no easy way to restart the syscall since other AIO's
-		 * may be already running. Just fail this IO with EINTR.
-		 */
-		if (unlikely(ret == -ERESTARTSYS || ret == -ERESTARTNOINTR ||
-			     ret == -ERESTARTNOHAND || ret == -ERESTART_RESTARTBLOCK))
-			ret = -EINTR;
-		aio_complete(iocb, ret, 0);
-	}
-out:
-	spin_lock_irq(&ctx->ctx_lock);
-
-	if (-EIOCBRETRY == ret) {
-		/*
-		 * OK, now that we are done with this iteration
-		 * and know that there is more left to go,
-		 * this is where we let go so that a subsequent
-		 * "kick" can start the next iteration
-		 */
-
-		/* will make __queue_kicked_iocb succeed from here on */
-		INIT_LIST_HEAD(&iocb->ki_run_list);
-		/* we must queue the next iteration ourselves, if it
-		 * has already been kicked */
-		if (kiocbIsKicked(iocb)) {
-			__queue_kicked_iocb(iocb);
-
-			/*
-			 * __queue_kicked_iocb will always return 1 here, because
-			 * iocb->ki_run_list is empty at this point so it should
-			 * be safe to unconditionally queue the context into the
-			 * work queue.
-			 */
-			aio_queue_work(ctx);
-		}
-	}
-	return ret;
-}
-
-/*
- * __aio_run_iocbs:
- * 	Process all pending retries queued on the ioctx
- * 	run list.
- * Assumes it is operating within the aio issuer's mm
- * context.
- */
-static int __aio_run_iocbs(struct kioctx *ctx)
-{
-	struct kiocb *iocb;
-	struct list_head run_list;
-
-	assert_spin_locked(&ctx->ctx_lock);
-
-	list_replace_init(&ctx->run_list, &run_list);
-	while (!list_empty(&run_list)) {
-		iocb = list_entry(run_list.next, struct kiocb,
-			ki_run_list);
-		list_del(&iocb->ki_run_list);
-		/*
-		 * Hold an extra reference while retrying i/o.
-		 */
-		iocb->ki_users++;       /* grab extra reference */
-		aio_run_iocb(iocb);
-		__aio_put_req(ctx, iocb);
- 	}
-	if (!list_empty(&ctx->run_list))
-		return 1;
-	return 0;
-}
-
-static void aio_queue_work(struct kioctx * ctx)
-{
-	unsigned long timeout;
-	/*
-	 * if someone is waiting, get the work started right
-	 * away, otherwise, use a longer delay
-	 */
-	smp_mb();
-	if (waitqueue_active(&ctx->wait))
-		timeout = 1;
-	else
-		timeout = HZ/10;
-	queue_delayed_work(aio_wq, &ctx->wq, timeout);
-}
-
-/*
- * aio_run_all_iocbs:
- *	Process all pending retries queued on the ioctx
- *	run list, and keep running them until the list
- *	stays empty.
- * Assumes it is operating within the aio issuer's mm context.
- */
-static inline void aio_run_all_iocbs(struct kioctx *ctx)
-{
-	spin_lock_irq(&ctx->ctx_lock);
-	while (__aio_run_iocbs(ctx))
-		;
-	spin_unlock_irq(&ctx->ctx_lock);
-}
-
-/*
- * aio_kick_handler:
- * 	Work queue handler triggered to process pending
- * 	retries on an ioctx. Takes on the aio issuer's
- *	mm context before running the iocbs, so that
- *	copy_xxx_user operates on the issuer's address
- *      space.
- * Run on aiod's context.
- */
-static void aio_kick_handler(struct work_struct *work)
-{
-	struct kioctx *ctx = container_of(work, struct kioctx, wq.work);
-	mm_segment_t oldfs = get_fs();
-	struct mm_struct *mm;
-	int requeue;
-
-	set_fs(USER_DS);
-	use_mm(ctx->mm);
-	spin_lock_irq(&ctx->ctx_lock);
-	requeue =__aio_run_iocbs(ctx);
-	mm = ctx->mm;
-	spin_unlock_irq(&ctx->ctx_lock);
- 	unuse_mm(mm);
-	set_fs(oldfs);
-	/*
-	 * we're in a worker thread already; no point using non-zero delay
-	 */
-	if (requeue)
-		queue_delayed_work(aio_wq, &ctx->wq, 0);
-}
-
-
-/*
- * Called by kick_iocb to queue the kiocb for retry
- * and if required activate the aio work queue to process
- * it
- */
-static void try_queue_kicked_iocb(struct kiocb *iocb)
-{
- 	struct kioctx	*ctx = iocb->ki_ctx;
-	unsigned long flags;
-	int run = 0;
-
-	spin_lock_irqsave(&ctx->ctx_lock, flags);
-	/* set this inside the lock so that we can't race with aio_run_iocb()
-	 * testing it and putting the iocb on the run list under the lock */
-	if (!kiocbTryKick(iocb))
-		run = __queue_kicked_iocb(iocb);
-	spin_unlock_irqrestore(&ctx->ctx_lock, flags);
-	if (run)
-		aio_queue_work(ctx);
-}
-
-/*
- * kick_iocb:
- *      Called typically from a wait queue callback context
- *      to trigger a retry of the iocb.
- *      The retry is usually executed by aio workqueue
- *      threads (See aio_kick_handler).
- */
-void kick_iocb(struct kiocb *iocb)
-{
-	/* sync iocbs are easy: they can only ever be executing from a 
-	 * single context. */
-	if (is_sync_kiocb(iocb)) {
-		kiocbSetKicked(iocb);
-	        wake_up_process(iocb->ki_obj.tsk);
-		return;
-	}
-
-	try_queue_kicked_iocb(iocb);
-}
-EXPORT_SYMBOL(kick_iocb);
-
 /* aio_complete
  *	Called when the io request on the given iocb is complete.
- *	Returns true if this is the last user of the request.  The 
- *	only other user of the request can be the cancellation code.
  */
-int aio_complete(struct kiocb *iocb, long res, long res2)
+void aio_complete(struct kiocb *iocb, long res, long res2)
 {
 	struct kioctx	*ctx = iocb->ki_ctx;
-	struct aio_ring_info	*info;
 	struct aio_ring	*ring;
-	struct io_event	*event;
+	struct io_event	*ev_page, *event;
 	unsigned long	flags;
-	unsigned long	tail;
-	int		ret;
+	unsigned tail, pos;
 
 	/*
 	 * Special case handling for sync iocbs:
@@ -909,61 +591,81 @@ int aio_complete(struct kiocb *iocb, long res, long res2)
 	 *  - the sync task helpfully left a reference to itself in the iocb
 	 */
 	if (is_sync_kiocb(iocb)) {
-		BUG_ON(iocb->ki_users != 1);
+		BUG_ON(atomic_read(&iocb->ki_users) != 1);
 		iocb->ki_user_data = res;
-		iocb->ki_users = 0;
+		atomic_set(&iocb->ki_users, 0);
 		wake_up_process(iocb->ki_obj.tsk);
-		return 1;
+		return;
 	}
 
-	info = &ctx->ring_info;
-
-	/* add a completion event to the ring buffer.
-	 * must be done holding ctx->ctx_lock to prevent
-	 * other code from messing with the tail
-	 * pointer since we might be called from irq
-	 * context.
+	/*
+	 * Take rcu_read_lock() in case the kioctx is being destroyed, as we
+	 * need to issue a wakeup after decrementing reqs_active.
 	 */
-	spin_lock_irqsave(&ctx->ctx_lock, flags);
+	rcu_read_lock();
 
-	if (iocb->ki_run_list.prev && !list_empty(&iocb->ki_run_list))
-		list_del_init(&iocb->ki_run_list);
+	if (iocb->ki_list.next) {
+		unsigned long flags;
+
+		spin_lock_irqsave(&ctx->ctx_lock, flags);
+		list_del(&iocb->ki_list);
+		spin_unlock_irqrestore(&ctx->ctx_lock, flags);
+	}
 
 	/*
 	 * cancelled requests don't get events, userland was given one
 	 * when the event got cancelled.
 	 */
-	if (kiocbIsCancelled(iocb))
+	if (unlikely(xchg(&iocb->ki_cancel,
+			  KIOCB_CANCELLED) == KIOCB_CANCELLED)) {
+		atomic_dec(&ctx->reqs_active);
+		/* Still need the wake_up in case free_ioctx is waiting */
 		goto put_rq;
+	}
 
-	ring = kmap_atomic(info->ring_pages[0]);
+	/*
+	 * Add a completion event to the ring buffer. Must be done holding
+	 * ctx->ctx_lock to prevent other code from messing with the tail
+	 * pointer since we might be called from irq context.
+	 */
+	spin_lock_irqsave(&ctx->completion_lock, flags);
 
-	tail = info->tail;
-	event = aio_ring_event(info, tail);
-	if (++tail >= info->nr)
+	tail = ctx->tail;
+	pos = tail + AIO_EVENTS_OFFSET;
+
+	if (++tail >= ctx->nr_events)
 		tail = 0;
 
+	ev_page = kmap_atomic(ctx->ring_pages[pos / AIO_EVENTS_PER_PAGE]);
+	event = ev_page + pos % AIO_EVENTS_PER_PAGE;
+
 	event->obj = (u64)(unsigned long)iocb->ki_obj.user;
 	event->data = iocb->ki_user_data;
 	event->res = res;
 	event->res2 = res2;
 
-	dprintk("aio_complete: %p[%lu]: %p: %p %Lx %lx %lx\n",
-		ctx, tail, iocb, iocb->ki_obj.user, iocb->ki_user_data,
-		res, res2);
+	kunmap_atomic(ev_page);
+	flush_dcache_page(ctx->ring_pages[pos / AIO_EVENTS_PER_PAGE]);
+
+	pr_debug("%p[%u]: %p: %p %Lx %lx %lx\n",
+		 ctx, tail, iocb, iocb->ki_obj.user, iocb->ki_user_data,
+		 res, res2);
 
 	/* after flagging the request as done, we
 	 * must never even look at it again
 	 */
 	smp_wmb();	/* make event visible before updating tail */
 
-	info->tail = tail;
-	ring->tail = tail;
+	ctx->tail = tail;
 
-	put_aio_ring_event(event);
+	ring = kmap_atomic(ctx->ring_pages[0]);
+	ring->tail = tail;
 	kunmap_atomic(ring);
+	flush_dcache_page(ctx->ring_pages[0]);
+
+	spin_unlock_irqrestore(&ctx->completion_lock, flags);
 
-	pr_debug("added to ring %p at [%lu]\n", iocb, tail);
+	pr_debug("added to ring %p at [%u]\n", iocb, tail);
 
 	/*
 	 * Check if the user asked us to deliver the result through an
@@ -975,7 +677,7 @@ int aio_complete(struct kiocb *iocb, long res, long res2)
 
 put_rq:
 	/* everything turned out well, dispose of the aiocb. */
-	ret = __aio_put_req(ctx, iocb);
+	aio_put_req(iocb);
 
 	/*
 	 * We have to order our ring_info tail store above and test
@@ -988,233 +690,133 @@ put_rq:
 	if (waitqueue_active(&ctx->wait))
 		wake_up(&ctx->wait);
 
-	spin_unlock_irqrestore(&ctx->ctx_lock, flags);
-	return ret;
+	rcu_read_unlock();
 }
 EXPORT_SYMBOL(aio_complete);
 
-/* aio_read_evt
- *	Pull an event off of the ioctx's event ring.  Returns the number of 
- *	events fetched (0 or 1 ;-)
- *	FIXME: make this use cmpxchg.
- *	TODO: make the ringbuffer user mmap()able (requires FIXME).
+/* aio_read_events
+ *	Pull an event off of the ioctx's event ring.  Returns the number of
+ *	events fetched
  */
-static int aio_read_evt(struct kioctx *ioctx, struct io_event *ent)
+static long aio_read_events_ring(struct kioctx *ctx,
+				 struct io_event __user *event, long nr)
 {
-	struct aio_ring_info *info = &ioctx->ring_info;
 	struct aio_ring *ring;
-	unsigned long head;
-	int ret = 0;
-
-	ring = kmap_atomic(info->ring_pages[0]);
-	dprintk("in aio_read_evt h%lu t%lu m%lu\n",
-		 (unsigned long)ring->head, (unsigned long)ring->tail,
-		 (unsigned long)ring->nr);
-
-	if (ring->head == ring->tail)
-		goto out;
+	unsigned head, pos;
+	long ret = 0;
+	int copy_ret;
 
-	spin_lock(&info->ring_lock);
-
-	head = ring->head % info->nr;
-	if (head != ring->tail) {
-		struct io_event *evp = aio_ring_event(info, head);
-		*ent = *evp;
-		head = (head + 1) % info->nr;
-		smp_mb(); /* finish reading the event before updatng the head */
-		ring->head = head;
-		ret = 1;
-		put_aio_ring_event(evp);
-	}
-	spin_unlock(&info->ring_lock);
+	mutex_lock(&ctx->ring_lock);
 
-out:
-	dprintk("leaving aio_read_evt: %d  h%lu t%lu\n", ret,
-		 (unsigned long)ring->head, (unsigned long)ring->tail);
+	ring = kmap_atomic(ctx->ring_pages[0]);
+	head = ring->head;
 	kunmap_atomic(ring);
-	return ret;
-}
 
-struct aio_timeout {
-	struct timer_list	timer;
-	int			timed_out;
-	struct task_struct	*p;
-};
+	pr_debug("h%u t%u m%u\n", head, ctx->tail, ctx->nr_events);
 
-static void timeout_func(unsigned long data)
-{
-	struct aio_timeout *to = (struct aio_timeout *)data;
+	if (head == ctx->tail)
+		goto out;
 
-	to->timed_out = 1;
-	wake_up_process(to->p);
-}
+	while (ret < nr) {
+		long avail;
+		struct io_event *ev;
+		struct page *page;
 
-static inline void init_timeout(struct aio_timeout *to)
-{
-	setup_timer_on_stack(&to->timer, timeout_func, (unsigned long) to);
-	to->timed_out = 0;
-	to->p = current;
-}
+		avail = (head <= ctx->tail ? ctx->tail : ctx->nr_events) - head;
+		if (head == ctx->tail)
+			break;
 
-static inline void set_timeout(long start_jiffies, struct aio_timeout *to,
-			       const struct timespec *ts)
-{
-	to->timer.expires = start_jiffies + timespec_to_jiffies(ts);
-	if (time_after(to->timer.expires, jiffies))
-		add_timer(&to->timer);
-	else
-		to->timed_out = 1;
-}
+		avail = min(avail, nr - ret);
+		avail = min_t(long, avail, AIO_EVENTS_PER_PAGE -
+			    ((head + AIO_EVENTS_OFFSET) % AIO_EVENTS_PER_PAGE));
 
-static inline void clear_timeout(struct aio_timeout *to)
-{
-	del_singleshot_timer_sync(&to->timer);
-}
+		pos = head + AIO_EVENTS_OFFSET;
+		page = ctx->ring_pages[pos / AIO_EVENTS_PER_PAGE];
+		pos %= AIO_EVENTS_PER_PAGE;
 
-static int read_events(struct kioctx *ctx,
-			long min_nr, long nr,
-			struct io_event __user *event,
-			struct timespec __user *timeout)
-{
-	long			start_jiffies = jiffies;
-	struct task_struct	*tsk = current;
-	DECLARE_WAITQUEUE(wait, tsk);
-	int			ret;
-	int			i = 0;
-	struct io_event		ent;
-	struct aio_timeout	to;
-	int			retry = 0;
-
-	/* needed to zero any padding within an entry (there shouldn't be 
-	 * any, but C is fun!
-	 */
-	memset(&ent, 0, sizeof(ent));
-retry:
-	ret = 0;
-	while (likely(i < nr)) {
-		ret = aio_read_evt(ctx, &ent);
-		if (unlikely(ret <= 0))
-			break;
-
-		dprintk("read event: %Lx %Lx %Lx %Lx\n",
-			ent.data, ent.obj, ent.res, ent.res2);
+		ev = kmap(page);
+		copy_ret = copy_to_user(event + ret, ev + pos,
+					sizeof(*ev) * avail);
+		kunmap(page);
 
-		/* Could we split the check in two? */
-		ret = -EFAULT;
-		if (unlikely(copy_to_user(event, &ent, sizeof(ent)))) {
-			dprintk("aio: lost an event due to EFAULT.\n");
-			break;
+		if (unlikely(copy_ret)) {
+			ret = -EFAULT;
+			goto out;
 		}
-		ret = 0;
 
-		/* Good, event copied to userland, update counts. */
-		event ++;
-		i ++;
+		ret += avail;
+		head += avail;
+		head %= ctx->nr_events;
 	}
 
-	if (min_nr <= i)
-		return i;
-	if (ret)
-		return ret;
+	ring = kmap_atomic(ctx->ring_pages[0]);
+	ring->head = head;
+	kunmap_atomic(ring);
+	flush_dcache_page(ctx->ring_pages[0]);
 
-	/* End fast path */
+	pr_debug("%li  h%u t%u\n", ret, head, ctx->tail);
 
-	/* racey check, but it gets redone */
-	if (!retry && unlikely(!list_empty(&ctx->run_list))) {
-		retry = 1;
-		aio_run_all_iocbs(ctx);
-		goto retry;
-	}
+	atomic_sub(ret, &ctx->reqs_active);
+out:
+	mutex_unlock(&ctx->ring_lock);
 
-	init_timeout(&to);
-	if (timeout) {
-		struct timespec	ts;
-		ret = -EFAULT;
-		if (unlikely(copy_from_user(&ts, timeout, sizeof(ts))))
-			goto out;
+	return ret;
+}
 
-		set_timeout(start_jiffies, &to, &ts);
-	}
+static bool aio_read_events(struct kioctx *ctx, long min_nr, long nr,
+			    struct io_event __user *event, long *i)
+{
+	long ret = aio_read_events_ring(ctx, event + *i, nr - *i);
 
-	while (likely(i < nr)) {
-		add_wait_queue_exclusive(&ctx->wait, &wait);
-		do {
-			set_task_state(tsk, TASK_INTERRUPTIBLE);
-			ret = aio_read_evt(ctx, &ent);
-			if (ret)
-				break;
-			if (min_nr <= i)
-				break;
-			if (unlikely(ctx->dead)) {
-				ret = -EINVAL;
-				break;
-			}
-			if (to.timed_out)	/* Only check after read evt */
-				break;
-			/* Try to only show up in io wait if there are ops
-			 *  in flight */
-			if (ctx->reqs_active)
-				io_schedule();
-			else
-				schedule();
-			if (signal_pending(tsk)) {
-				ret = -EINTR;
-				break;
-			}
-			/*ret = aio_read_evt(ctx, &ent);*/
-		} while (1) ;
-
-		set_task_state(tsk, TASK_RUNNING);
-		remove_wait_queue(&ctx->wait, &wait);
-
-		if (unlikely(ret <= 0))
-			break;
+	if (ret > 0)
+		*i += ret;
 
-		ret = -EFAULT;
-		if (unlikely(copy_to_user(event, &ent, sizeof(ent)))) {
-			dprintk("aio: lost an event due to EFAULT.\n");
-			break;
-		}
+	if (unlikely(atomic_read(&ctx->dead)))
+		ret = -EINVAL;
 
-		/* Good, event copied to userland, update counts. */
-		event ++;
-		i ++;
-	}
+	if (!*i)
+		*i = ret;
 
-	if (timeout)
-		clear_timeout(&to);
-out:
-	destroy_timer_on_stack(&to.timer);
-	return i ? i : ret;
+	return ret < 0 || *i >= min_nr;
 }
 
-/* Take an ioctx and remove it from the list of ioctx's.  Protects 
- * against races with itself via ->dead.
- */
-static void io_destroy(struct kioctx *ioctx)
+static long read_events(struct kioctx *ctx, long min_nr, long nr,
+			struct io_event __user *event,
+			struct timespec __user *timeout)
 {
-	struct mm_struct *mm = current->mm;
-	int was_dead;
+	ktime_t until = { .tv64 = KTIME_MAX };
+	long ret = 0;
 
-	/* delete the entry from the list is someone else hasn't already */
-	spin_lock(&mm->ioctx_lock);
-	was_dead = ioctx->dead;
-	ioctx->dead = 1;
-	hlist_del_rcu(&ioctx->list);
-	spin_unlock(&mm->ioctx_lock);
+	if (timeout) {
+		struct timespec	ts;
 
-	dprintk("aio_release(%p)\n", ioctx);
-	if (likely(!was_dead))
-		put_ioctx(ioctx);	/* twice for the list */
+		if (unlikely(copy_from_user(&ts, timeout, sizeof(ts))))
+			return -EFAULT;
 
-	kill_ctx(ioctx);
+		until = timespec_to_ktime(ts);
+	}
 
 	/*
-	 * Wake up any waiters.  The setting of ctx->dead must be seen
-	 * by other CPUs at this point.  Right now, we rely on the
-	 * locking done by the above calls to ensure this consistency.
+	 * Note that aio_read_events() is being called as the conditional - i.e.
+	 * we're calling it after prepare_to_wait() has set task state to
+	 * TASK_INTERRUPTIBLE.
+	 *
+	 * But aio_read_events() can block, and if it blocks it's going to flip
+	 * the task state back to TASK_RUNNING.
+	 *
+	 * This should be ok, provided it doesn't flip the state back to
+	 * TASK_RUNNING and return 0 too much - that causes us to spin. That
+	 * will only happen if the mutex_lock() call blocks, and we then find
+	 * the ringbuffer empty. So in practice we should be ok, but it's
+	 * something to be aware of when touching this code.
 	 */
-	wake_up_all(&ioctx->wait);
+	wait_event_interruptible_hrtimeout(ctx->wait,
+			aio_read_events(ctx, min_nr, nr, event, &ret), until);
+
+	if (!ret && signal_pending(current))
+		ret = -EINTR;
+
+	return ret;
 }
 
 /* sys_io_setup:
@@ -1252,7 +854,7 @@ SYSCALL_DEFINE2(io_setup, unsigned, nr_events, aio_context_t __user *, ctxp)
 	if (!IS_ERR(ioctx)) {
 		ret = put_user(ioctx->user_id, ctxp);
 		if (ret)
-			io_destroy(ioctx);
+			kill_ioctx(ioctx);
 		put_ioctx(ioctx);
 	}
 
@@ -1270,7 +872,7 @@ SYSCALL_DEFINE1(io_destroy, aio_context_t, ctx)
 {
 	struct kioctx *ioctx = lookup_ioctx(ctx);
 	if (likely(NULL != ioctx)) {
-		io_destroy(ioctx);
+		kill_ioctx(ioctx);
 		put_ioctx(ioctx);
 		return 0;
 	}
@@ -1301,30 +903,21 @@ static void aio_advance_iovec(struct kiocb *iocb, ssize_t ret)
 	BUG_ON(ret > 0 && iocb->ki_left == 0);
 }
 
-static ssize_t aio_rw_vect_retry(struct kiocb *iocb)
+typedef ssize_t (aio_rw_op)(struct kiocb *, const struct iovec *,
+			    unsigned long, loff_t);
+
+static ssize_t aio_rw_vect_retry(struct kiocb *iocb, int rw, aio_rw_op *rw_op)
 {
 	struct file *file = iocb->ki_filp;
 	struct address_space *mapping = file->f_mapping;
 	struct inode *inode = mapping->host;
-	ssize_t (*rw_op)(struct kiocb *, const struct iovec *,
-			 unsigned long, loff_t);
 	ssize_t ret = 0;
-	unsigned short opcode;
-
-	if ((iocb->ki_opcode == IOCB_CMD_PREADV) ||
-		(iocb->ki_opcode == IOCB_CMD_PREAD)) {
-		rw_op = file->f_op->aio_read;
-		opcode = IOCB_CMD_PREADV;
-	} else {
-		rw_op = file->f_op->aio_write;
-		opcode = IOCB_CMD_PWRITEV;
-	}
 
 	/* This matches the pread()/pwrite() logic */
 	if (iocb->ki_pos < 0)
 		return -EINVAL;
 
-	if (opcode == IOCB_CMD_PWRITEV)
+	if (rw == WRITE)
 		file_start_write(file);
 	do {
 		ret = rw_op(iocb, &iocb->ki_iovec[iocb->ki_cur_seg],
@@ -1336,9 +929,9 @@ static ssize_t aio_rw_vect_retry(struct kiocb *iocb)
 	/* retry all partial writes.  retry partial reads as long as its a
 	 * regular file. */
 	} while (ret > 0 && iocb->ki_left > 0 &&
-		 (opcode == IOCB_CMD_PWRITEV ||
+		 (rw == WRITE ||
 		  (!S_ISFIFO(inode->i_mode) && !S_ISSOCK(inode->i_mode))));
-	if (opcode == IOCB_CMD_PWRITEV)
+	if (rw == WRITE)
 		file_end_write(file);
 
 	/* This means we must have transferred all that we could */
@@ -1348,81 +941,49 @@ static ssize_t aio_rw_vect_retry(struct kiocb *iocb)
 
 	/* If we managed to write some out we return that, rather than
 	 * the eventual error. */
-	if (opcode == IOCB_CMD_PWRITEV
-	    && ret < 0 && ret != -EIOCBQUEUED && ret != -EIOCBRETRY
+	if (rw == WRITE
+	    && ret < 0 && ret != -EIOCBQUEUED
 	    && iocb->ki_nbytes - iocb->ki_left)
 		ret = iocb->ki_nbytes - iocb->ki_left;
 
 	return ret;
 }
 
-static ssize_t aio_fdsync(struct kiocb *iocb)
-{
-	struct file *file = iocb->ki_filp;
-	ssize_t ret = -EINVAL;
-
-	if (file->f_op->aio_fsync)
-		ret = file->f_op->aio_fsync(iocb, 1);
-	return ret;
-}
-
-static ssize_t aio_fsync(struct kiocb *iocb)
-{
-	struct file *file = iocb->ki_filp;
-	ssize_t ret = -EINVAL;
-
-	if (file->f_op->aio_fsync)
-		ret = file->f_op->aio_fsync(iocb, 0);
-	return ret;
-}
-
-static ssize_t aio_setup_vectored_rw(int type, struct kiocb *kiocb, bool compat)
+static ssize_t aio_setup_vectored_rw(int rw, struct kiocb *kiocb, bool compat)
 {
 	ssize_t ret;
 
+	kiocb->ki_nr_segs = kiocb->ki_nbytes;
+
 #ifdef CONFIG_COMPAT
 	if (compat)
-		ret = compat_rw_copy_check_uvector(type,
+		ret = compat_rw_copy_check_uvector(rw,
 				(struct compat_iovec __user *)kiocb->ki_buf,
-				kiocb->ki_nbytes, 1, &kiocb->ki_inline_vec,
+				kiocb->ki_nr_segs, 1, &kiocb->ki_inline_vec,
 				&kiocb->ki_iovec);
 	else
 #endif
-		ret = rw_copy_check_uvector(type,
+		ret = rw_copy_check_uvector(rw,
 				(struct iovec __user *)kiocb->ki_buf,
-				kiocb->ki_nbytes, 1, &kiocb->ki_inline_vec,
+				kiocb->ki_nr_segs, 1, &kiocb->ki_inline_vec,
 				&kiocb->ki_iovec);
 	if (ret < 0)
-		goto out;
-
-	ret = rw_verify_area(type, kiocb->ki_filp, &kiocb->ki_pos, ret);
-	if (ret < 0)
-		goto out;
+		return ret;
 
-	kiocb->ki_nr_segs = kiocb->ki_nbytes;
-	kiocb->ki_cur_seg = 0;
-	/* ki_nbytes/left now reflect bytes instead of segs */
+	/* ki_nbytes now reflect bytes instead of segs */
 	kiocb->ki_nbytes = ret;
-	kiocb->ki_left = ret;
-
-	ret = 0;
-out:
-	return ret;
+	return 0;
 }
 
-static ssize_t aio_setup_single_vector(int type, struct file * file, struct kiocb *kiocb)
+static ssize_t aio_setup_single_vector(int rw, struct kiocb *kiocb)
 {
-	int bytes;
-
-	bytes = rw_verify_area(type, file, &kiocb->ki_pos, kiocb->ki_left);
-	if (bytes < 0)
-		return bytes;
+	if (unlikely(!access_ok(!rw, kiocb->ki_buf, kiocb->ki_nbytes)))
+		return -EFAULT;
 
 	kiocb->ki_iovec = &kiocb->ki_inline_vec;
 	kiocb->ki_iovec->iov_base = kiocb->ki_buf;
-	kiocb->ki_iovec->iov_len = bytes;
+	kiocb->ki_iovec->iov_len = kiocb->ki_nbytes;
 	kiocb->ki_nr_segs = 1;
-	kiocb->ki_cur_seg = 0;
 	return 0;
 }
 
@@ -1431,96 +992,95 @@ static ssize_t aio_setup_single_vector(int type, struct file * file, struct kioc
  *	Performs the initial checks and aio retry method
  *	setup for the kiocb at the time of io submission.
  */
-static ssize_t aio_setup_iocb(struct kiocb *kiocb, bool compat)
+static ssize_t aio_run_iocb(struct kiocb *req, bool compat)
 {
-	struct file *file = kiocb->ki_filp;
-	ssize_t ret = 0;
+	struct file *file = req->ki_filp;
+	ssize_t ret;
+	int rw;
+	fmode_t mode;
+	aio_rw_op *rw_op;
 
-	switch (kiocb->ki_opcode) {
+	switch (req->ki_opcode) {
 	case IOCB_CMD_PREAD:
-		ret = -EBADF;
-		if (unlikely(!(file->f_mode & FMODE_READ)))
-			break;
-		ret = -EFAULT;
-		if (unlikely(!access_ok(VERIFY_WRITE, kiocb->ki_buf,
-			kiocb->ki_left)))
-			break;
-		ret = aio_setup_single_vector(READ, file, kiocb);
-		if (ret)
-			break;
-		ret = -EINVAL;
-		if (file->f_op->aio_read)
-			kiocb->ki_retry = aio_rw_vect_retry;
-		break;
-	case IOCB_CMD_PWRITE:
-		ret = -EBADF;
-		if (unlikely(!(file->f_mode & FMODE_WRITE)))
-			break;
-		ret = -EFAULT;
-		if (unlikely(!access_ok(VERIFY_READ, kiocb->ki_buf,
-			kiocb->ki_left)))
-			break;
-		ret = aio_setup_single_vector(WRITE, file, kiocb);
-		if (ret)
-			break;
-		ret = -EINVAL;
-		if (file->f_op->aio_write)
-			kiocb->ki_retry = aio_rw_vect_retry;
-		break;
 	case IOCB_CMD_PREADV:
-		ret = -EBADF;
-		if (unlikely(!(file->f_mode & FMODE_READ)))
-			break;
-		ret = aio_setup_vectored_rw(READ, kiocb, compat);
-		if (ret)
-			break;
-		ret = -EINVAL;
-		if (file->f_op->aio_read)
-			kiocb->ki_retry = aio_rw_vect_retry;
-		break;
+		mode	= FMODE_READ;
+		rw	= READ;
+		rw_op	= file->f_op->aio_read;
+		goto rw_common;
+
+	case IOCB_CMD_PWRITE:
 	case IOCB_CMD_PWRITEV:
-		ret = -EBADF;
-		if (unlikely(!(file->f_mode & FMODE_WRITE)))
-			break;
-		ret = aio_setup_vectored_rw(WRITE, kiocb, compat);
+		mode	= FMODE_WRITE;
+		rw	= WRITE;
+		rw_op	= file->f_op->aio_write;
+		goto rw_common;
+rw_common:
+		if (unlikely(!(file->f_mode & mode)))
+			return -EBADF;
+
+		if (!rw_op)
+			return -EINVAL;
+
+		ret = (req->ki_opcode == IOCB_CMD_PREADV ||
+		       req->ki_opcode == IOCB_CMD_PWRITEV)
+			? aio_setup_vectored_rw(rw, req, compat)
+			: aio_setup_single_vector(rw, req);
 		if (ret)
-			break;
-		ret = -EINVAL;
-		if (file->f_op->aio_write)
-			kiocb->ki_retry = aio_rw_vect_retry;
+			return ret;
+
+		ret = rw_verify_area(rw, file, &req->ki_pos, req->ki_nbytes);
+		if (ret < 0)
+			return ret;
+
+		req->ki_nbytes = ret;
+		req->ki_left = ret;
+
+		ret = aio_rw_vect_retry(req, rw, rw_op);
 		break;
+
 	case IOCB_CMD_FDSYNC:
-		ret = -EINVAL;
-		if (file->f_op->aio_fsync)
-			kiocb->ki_retry = aio_fdsync;
+		if (!file->f_op->aio_fsync)
+			return -EINVAL;
+
+		ret = file->f_op->aio_fsync(req, 1);
 		break;
+
 	case IOCB_CMD_FSYNC:
-		ret = -EINVAL;
-		if (file->f_op->aio_fsync)
-			kiocb->ki_retry = aio_fsync;
+		if (!file->f_op->aio_fsync)
+			return -EINVAL;
+
+		ret = file->f_op->aio_fsync(req, 0);
 		break;
+
 	default:
-		dprintk("EINVAL: io_submit: no operation provided\n");
-		ret = -EINVAL;
+		pr_debug("EINVAL: no operation provided\n");
+		return -EINVAL;
 	}
 
-	if (!kiocb->ki_retry)
-		return ret;
+	if (ret != -EIOCBQUEUED) {
+		/*
+		 * There's no easy way to restart the syscall since other AIO's
+		 * may be already running. Just fail this IO with EINTR.
+		 */
+		if (unlikely(ret == -ERESTARTSYS || ret == -ERESTARTNOINTR ||
+			     ret == -ERESTARTNOHAND ||
+			     ret == -ERESTART_RESTARTBLOCK))
+			ret = -EINTR;
+		aio_complete(req, ret, 0);
+	}
 
 	return 0;
 }
 
 static int io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb,
-			 struct iocb *iocb, struct kiocb_batch *batch,
-			 bool compat)
+			 struct iocb *iocb, bool compat)
 {
 	struct kiocb *req;
-	struct file *file;
 	ssize_t ret;
 
 	/* enforce forwards compatibility on users */
 	if (unlikely(iocb->aio_reserved1 || iocb->aio_reserved2)) {
-		pr_debug("EINVAL: io_submit: reserve field set\n");
+		pr_debug("EINVAL: reserve field set\n");
 		return -EINVAL;
 	}
 
@@ -1534,16 +1094,16 @@ static int io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb,
 		return -EINVAL;
 	}
 
-	file = fget(iocb->aio_fildes);
-	if (unlikely(!file))
-		return -EBADF;
-
-	req = aio_get_req(ctx, batch);  /* returns with 2 references to req */
-	if (unlikely(!req)) {
-		fput(file);
+	req = aio_get_req(ctx);
+	if (unlikely(!req))
 		return -EAGAIN;
+
+	req->ki_filp = fget(iocb->aio_fildes);
+	if (unlikely(!req->ki_filp)) {
+		ret = -EBADF;
+		goto out_put_req;
 	}
-	req->ki_filp = file;
+
 	if (iocb->aio_flags & IOCB_FLAG_RESFD) {
 		/*
 		 * If the IOCB_FLAG_RESFD flag of aio_flags is set, get an
@@ -1559,9 +1119,9 @@ static int io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb,
 		}
 	}
 
-	ret = put_user(req->ki_key, &user_iocb->aio_key);
+	ret = put_user(KIOCB_KEY, &user_iocb->aio_key);
 	if (unlikely(ret)) {
-		dprintk("EFAULT: aio_key\n");
+		pr_debug("EFAULT: aio_key\n");
 		goto out_put_req;
 	}
 
@@ -1573,41 +1133,14 @@ static int io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb,
 	req->ki_left = req->ki_nbytes = iocb->aio_nbytes;
 	req->ki_opcode = iocb->aio_lio_opcode;
 
-	ret = aio_setup_iocb(req, compat);
-
+	ret = aio_run_iocb(req, compat);
 	if (ret)
 		goto out_put_req;
 
-	spin_lock_irq(&ctx->ctx_lock);
-	/*
-	 * We could have raced with io_destroy() and are currently holding a
-	 * reference to ctx which should be destroyed. We cannot submit IO
-	 * since ctx gets freed as soon as io_submit() puts its reference.  The
-	 * check here is reliable: io_destroy() sets ctx->dead before waiting
-	 * for outstanding IO and the barrier between these two is realized by
-	 * unlock of mm->ioctx_lock and lock of ctx->ctx_lock.  Analogously we
-	 * increment ctx->reqs_active before checking for ctx->dead and the
-	 * barrier is realized by unlock and lock of ctx->ctx_lock. Thus if we
-	 * don't see ctx->dead set here, io_destroy() waits for our IO to
-	 * finish.
-	 */
-	if (ctx->dead) {
-		spin_unlock_irq(&ctx->ctx_lock);
-		ret = -EINVAL;
-		goto out_put_req;
-	}
-	aio_run_iocb(req);
-	if (!list_empty(&ctx->run_list)) {
-		/* drain the run list */
-		while (__aio_run_iocbs(ctx))
-			;
-	}
-	spin_unlock_irq(&ctx->ctx_lock);
-
 	aio_put_req(req);	/* drop extra ref to req */
 	return 0;
-
 out_put_req:
+	atomic_dec(&ctx->reqs_active);
 	aio_put_req(req);	/* drop extra ref to req */
 	aio_put_req(req);	/* drop i/o ref to req */
 	return ret;
@@ -1620,7 +1153,6 @@ long do_io_submit(aio_context_t ctx_id, long nr,
 	long ret = 0;
 	int i = 0;
 	struct blk_plug plug;
-	struct kiocb_batch batch;
 
 	if (unlikely(nr < 0))
 		return -EINVAL;
@@ -1633,12 +1165,10 @@ long do_io_submit(aio_context_t ctx_id, long nr,
 
 	ctx = lookup_ioctx(ctx_id);
 	if (unlikely(!ctx)) {
-		pr_debug("EINVAL: io_submit: invalid context id\n");
+		pr_debug("EINVAL: invalid context id\n");
 		return -EINVAL;
 	}
 
-	kiocb_batch_init(&batch, nr);
-
 	blk_start_plug(&plug);
 
 	/*
@@ -1659,13 +1189,12 @@ long do_io_submit(aio_context_t ctx_id, long nr,
 			break;
 		}
 
-		ret = io_submit_one(ctx, user_iocb, &tmp, &batch, compat);
+		ret = io_submit_one(ctx, user_iocb, &tmp, compat);
 		if (ret)
 			break;
 	}
 	blk_finish_plug(&plug);
 
-	kiocb_batch_free(ctx, &batch);
 	put_ioctx(ctx);
 	return i ? i : ret;
 }
@@ -1698,10 +1227,13 @@ static struct kiocb *lookup_kiocb(struct kioctx *ctx, struct iocb __user *iocb,
 
 	assert_spin_locked(&ctx->ctx_lock);
 
+	if (key != KIOCB_KEY)
+		return NULL;
+
 	/* TODO: use a hash or array, this sucks. */
 	list_for_each(pos, &ctx->active_reqs) {
 		struct kiocb *kiocb = list_kiocb(pos);
-		if (kiocb->ki_obj.user == iocb && kiocb->ki_key == key)
+		if (kiocb->ki_obj.user == iocb)
 			return kiocb;
 	}
 	return NULL;
@@ -1720,7 +1252,7 @@ static struct kiocb *lookup_kiocb(struct kioctx *ctx, struct iocb __user *iocb,
 SYSCALL_DEFINE3(io_cancel, aio_context_t, ctx_id, struct iocb __user *, iocb,
 		struct io_event __user *, result)
 {
-	int (*cancel)(struct kiocb *iocb, struct io_event *res);
+	struct io_event res;
 	struct kioctx *ctx;
 	struct kiocb *kiocb;
 	u32 key;
@@ -1735,32 +1267,22 @@ SYSCALL_DEFINE3(io_cancel, aio_context_t, ctx_id, struct iocb __user *, iocb,
 		return -EINVAL;
 
 	spin_lock_irq(&ctx->ctx_lock);
-	ret = -EAGAIN;
+
 	kiocb = lookup_kiocb(ctx, iocb, key);
-	if (kiocb && kiocb->ki_cancel) {
-		cancel = kiocb->ki_cancel;
-		kiocb->ki_users ++;
-		kiocbSetCancelled(kiocb);
-	} else
-		cancel = NULL;
+	if (kiocb)
+		ret = kiocb_cancel(ctx, kiocb, &res);
+	else
+		ret = -EINVAL;
+
 	spin_unlock_irq(&ctx->ctx_lock);
 
-	if (NULL != cancel) {
-		struct io_event tmp;
-		pr_debug("calling cancel\n");
-		memset(&tmp, 0, sizeof(tmp));
-		tmp.obj = (u64)(unsigned long)kiocb->ki_obj.user;
-		tmp.data = kiocb->ki_user_data;
-		ret = cancel(kiocb, &tmp);
-		if (!ret) {
-			/* Cancellation succeeded -- copy the result
-			 * into the user's buffer.
-			 */
-			if (copy_to_user(result, &tmp, sizeof(tmp)))
-				ret = -EFAULT;
-		}
-	} else
-		ret = -EINVAL;
+	if (!ret) {
+		/* Cancellation succeeded -- copy the result
+		 * into the user's buffer.
+		 */
+		if (copy_to_user(result, &res, sizeof(res)))
+			ret = -EFAULT;
+	}
 
 	put_ioctx(ctx);
 
diff --git a/fs/bio.c b/fs/bio.c
index b96fc6ce485..954d73124b4 100644
--- a/fs/bio.c
+++ b/fs/bio.c
@@ -19,6 +19,7 @@
 #include <linux/swap.h>
 #include <linux/bio.h>
 #include <linux/blkdev.h>
+#include <linux/uio.h>
 #include <linux/iocontext.h>
 #include <linux/slab.h>
 #include <linux/init.h>
diff --git a/fs/block_dev.c b/fs/block_dev.c
index 3823d3ffb76..d9871c1f089 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -27,6 +27,7 @@
 #include <linux/namei.h>
 #include <linux/log2.h>
 #include <linux/cleancache.h>
+#include <linux/aio.h>
 #include <asm/uaccess.h>
 #include "internal.h"
 
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index bb8b7a0e28a..bc4d54c465a 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -24,6 +24,7 @@
 #include <linux/string.h>
 #include <linux/backing-dev.h>
 #include <linux/mpage.h>
+#include <linux/aio.h>
 #include <linux/falloc.h>
 #include <linux/swap.h>
 #include <linux/writeback.h>
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 09c58a35b42..898da0a01e0 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -32,6 +32,7 @@
 #include <linux/writeback.h>
 #include <linux/statfs.h>
 #include <linux/compat.h>
+#include <linux/aio.h>
 #include <linux/bit_spinlock.h>
 #include <linux/xattr.h>
 #include <linux/posix_acl.h>
diff --git a/fs/ceph/file.c b/fs/ceph/file.c
index d70830c6683..656e1690743 100644
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -7,6 +7,7 @@
 #include <linux/mount.h>
 #include <linux/namei.h>
 #include <linux/writeback.h>
+#include <linux/aio.h>
 
 #include "super.h"
 #include "mds_client.h"
diff --git a/fs/compat.c b/fs/compat.c
index 93f7d021b71..fc3b55dce18 100644
--- a/fs/compat.c
+++ b/fs/compat.c
@@ -47,6 +47,7 @@
 #include <linux/fs_struct.h>
 #include <linux/slab.h>
 #include <linux/pagemap.h>
+#include <linux/aio.h>
 
 #include <asm/uaccess.h>
 #include <asm/mmu_context.h>
diff --git a/fs/direct-io.c b/fs/direct-io.c
index cfb816dc6d9..51d16e067d6 100644
--- a/fs/direct-io.c
+++ b/fs/direct-io.c
@@ -37,6 +37,7 @@
 #include <linux/uio.h>
 #include <linux/atomic.h>
 #include <linux/prefetch.h>
+#include <linux/aio.h>
 
 /*
  * How many user pages to map in one call to get_user_pages().  This determines
diff --git a/fs/ecryptfs/file.c b/fs/ecryptfs/file.c
index 63b1f54b6a1..201f0a0d6b0 100644
--- a/fs/ecryptfs/file.c
+++ b/fs/ecryptfs/file.c
@@ -31,6 +31,7 @@
 #include <linux/security.h>
 #include <linux/compat.h>
 #include <linux/fs_stack.h>
+#include <linux/aio.h>
 #include "ecryptfs_kernel.h"
 
 /**
diff --git a/fs/ext2/inode.c b/fs/ext2/inode.c
index fe60cc1117d..0a87bb10998 100644
--- a/fs/ext2/inode.c
+++ b/fs/ext2/inode.c
@@ -31,6 +31,7 @@
 #include <linux/mpage.h>
 #include <linux/fiemap.h>
 #include <linux/namei.h>
+#include <linux/aio.h>
 #include "ext2.h"
 #include "acl.h"
 #include "xip.h"
diff --git a/fs/ext3/inode.c b/fs/ext3/inode.c
index d706dbfa622..23c71282564 100644
--- a/fs/ext3/inode.c
+++ b/fs/ext3/inode.c
@@ -27,6 +27,7 @@
 #include <linux/writeback.h>
 #include <linux/mpage.h>
 #include <linux/namei.h>
+#include <linux/aio.h>
 #include "ext3.h"
 #include "xattr.h"
 #include "acl.h"
diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index 64848b595b2..4959e29573b 100644
--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c
@@ -23,6 +23,7 @@
 #include <linux/jbd2.h>
 #include <linux/mount.h>
 #include <linux/path.h>
+#include <linux/aio.h>
 #include <linux/quotaops.h>
 #include <linux/pagevec.h>
 #include "ext4.h"
diff --git a/fs/ext4/indirect.c b/fs/ext4/indirect.c
index 98be6f69746..b8d5d351e24 100644
--- a/fs/ext4/indirect.c
+++ b/fs/ext4/indirect.c
@@ -20,6 +20,7 @@
  *	(sct@redhat.com), 1993, 1998
  */
 
+#include <linux/aio.h>
 #include "ext4_jbd2.h"
 #include "truncate.h"
 #include "ext4_extents.h"	/* Needed for EXT_MAX_BLOCKS */
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 793d44b84d7..0723774bdfb 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -37,6 +37,7 @@
 #include <linux/printk.h>
 #include <linux/slab.h>
 #include <linux/ratelimit.h>
+#include <linux/aio.h>
 
 #include "ext4_jbd2.h"
 #include "xattr.h"
diff --git a/fs/ext4/page-io.c b/fs/ext4/page-io.c
index 5929cd0baa2..19599bded62 100644
--- a/fs/ext4/page-io.c
+++ b/fs/ext4/page-io.c
@@ -18,6 +18,7 @@
 #include <linux/pagevec.h>
 #include <linux/mpage.h>
 #include <linux/namei.h>
+#include <linux/aio.h>
 #include <linux/uio.h>
 #include <linux/bio.h>
 #include <linux/workqueue.h>
diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 7bd22a20112..d0ed4ba4b61 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -12,6 +12,7 @@
 #include <linux/f2fs_fs.h>
 #include <linux/buffer_head.h>
 #include <linux/mpage.h>
+#include <linux/aio.h>
 #include <linux/writeback.h>
 #include <linux/backing-dev.h>
 #include <linux/blkdev.h>
diff --git a/fs/fat/inode.c b/fs/fat/inode.c
index 4ff901632b2..dfce656ddb3 100644
--- a/fs/fat/inode.c
+++ b/fs/fat/inode.c
@@ -19,6 +19,7 @@
 #include <linux/mpage.h>
 #include <linux/buffer_head.h>
 #include <linux/mount.h>
+#include <linux/aio.h>
 #include <linux/vfs.h>
 #include <linux/parser.h>
 #include <linux/uio.h>
diff --git a/fs/fuse/cuse.c b/fs/fuse/cuse.c
index b3aaf7b3578..aef34b1e635 100644
--- a/fs/fuse/cuse.c
+++ b/fs/fuse/cuse.c
@@ -38,6 +38,7 @@
 #include <linux/device.h>
 #include <linux/file.h>
 #include <linux/fs.h>
+#include <linux/aio.h>
 #include <linux/kdev_t.h>
 #include <linux/kthread.h>
 #include <linux/list.h>
diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index a6c1664e330..1d55f946540 100644
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -19,6 +19,7 @@
 #include <linux/pipe_fs_i.h>
 #include <linux/swap.h>
 #include <linux/splice.h>
+#include <linux/aio.h>
 
 MODULE_ALIAS_MISCDEV(FUSE_MINOR);
 MODULE_ALIAS("devname:fuse");
diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index 4655e59d545..d1c9b85b3f5 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -15,6 +15,7 @@
 #include <linux/module.h>
 #include <linux/compat.h>
 #include <linux/swap.h>
+#include <linux/aio.h>
 
 static const struct file_operations fuse_direct_io_file_operations;
 
diff --git a/fs/gfs2/aops.c b/fs/gfs2/aops.c
index 9883694f1e7..0bad69ed633 100644
--- a/fs/gfs2/aops.c
+++ b/fs/gfs2/aops.c
@@ -20,6 +20,7 @@
 #include <linux/swap.h>
 #include <linux/gfs2_ondisk.h>
 #include <linux/backing-dev.h>
+#include <linux/aio.h>
 
 #include "gfs2.h"
 #include "incore.h"
diff --git a/fs/gfs2/file.c b/fs/gfs2/file.c
index d79c2dadc53..acd16764b13 100644
--- a/fs/gfs2/file.c
+++ b/fs/gfs2/file.c
@@ -25,6 +25,7 @@
 #include <asm/uaccess.h>
 #include <linux/dlm.h>
 #include <linux/dlm_plock.h>
+#include <linux/aio.h>
 
 #include "gfs2.h"
 #include "incore.h"
diff --git a/fs/hfs/inode.c b/fs/hfs/inode.c
index 716e1aafb2e..f9299d8a64e 100644
--- a/fs/hfs/inode.c
+++ b/fs/hfs/inode.c
@@ -14,6 +14,7 @@
 #include <linux/pagemap.h>
 #include <linux/mpage.h>
 #include <linux/sched.h>
+#include <linux/aio.h>
 
 #include "hfs_fs.h"
 #include "btree.h"
diff --git a/fs/hfsplus/inode.c b/fs/hfsplus/inode.c
index 7faaa964968..f833d35630a 100644
--- a/fs/hfsplus/inode.c
+++ b/fs/hfsplus/inode.c
@@ -14,6 +14,7 @@
 #include <linux/pagemap.h>
 #include <linux/mpage.h>
 #include <linux/sched.h>
+#include <linux/aio.h>
 
 #include "hfsplus_fs.h"
 #include "hfsplus_raw.h"
diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index 523464e6284..a3f868ae3fd 100644
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -909,11 +909,8 @@ static int can_do_hugetlb_shm(void)
 
 static int get_hstate_idx(int page_size_log)
 {
-	struct hstate *h;
+	struct hstate *h = hstate_sizelog(page_size_log);
 
-	if (!page_size_log)
-		return default_hstate_idx;
-	h = size_to_hstate(1 << page_size_log);
 	if (!h)
 		return -1;
 	return h - hstates;
@@ -929,9 +926,12 @@ static struct dentry_operations anon_ops = {
 	.d_dname = hugetlb_dname
 };
 
-struct file *hugetlb_file_setup(const char *name, unsigned long addr,
-				size_t size, vm_flags_t acctflag,
-				struct user_struct **user,
+/*
+ * Note that size should be aligned to proper hugepage size in caller side,
+ * otherwise hugetlb_reserve_pages reserves one less hugepages than intended.
+ */
+struct file *hugetlb_file_setup(const char *name, size_t size,
+				vm_flags_t acctflag, struct user_struct **user,
 				int creat_flags, int page_size_log)
 {
 	struct file *file = ERR_PTR(-ENOMEM);
@@ -939,8 +939,6 @@ struct file *hugetlb_file_setup(const char *name, unsigned long addr,
 	struct path path;
 	struct super_block *sb;
 	struct qstr quick_string;
-	struct hstate *hstate;
-	unsigned long num_pages;
 	int hstate_idx;
 
 	hstate_idx = get_hstate_idx(page_size_log);
@@ -980,12 +978,10 @@ struct file *hugetlb_file_setup(const char *name, unsigned long addr,
 	if (!inode)
 		goto out_dentry;
 
-	hstate = hstate_inode(inode);
-	size += addr & ~huge_page_mask(hstate);
-	num_pages = ALIGN(size, huge_page_size(hstate)) >>
-			huge_page_shift(hstate);
 	file = ERR_PTR(-ENOMEM);
-	if (hugetlb_reserve_pages(inode, 0, num_pages, NULL, acctflag))
+	if (hugetlb_reserve_pages(inode, 0,
+			size >> huge_page_shift(hstate_inode(inode)), NULL,
+			acctflag))
 		goto out_inode;
 
 	d_instantiate(path.dentry, inode);
diff --git a/fs/jfs/inode.c b/fs/jfs/inode.c
index 77554b61d12..730f24e282a 100644
--- a/fs/jfs/inode.c
+++ b/fs/jfs/inode.c
@@ -23,6 +23,7 @@
 #include <linux/pagemap.h>
 #include <linux/quotaops.h>
 #include <linux/writeback.h>
+#include <linux/aio.h>
 #include "jfs_incore.h"
 #include "jfs_inode.h"
 #include "jfs_filsys.h"
diff --git a/fs/nilfs2/inode.c b/fs/nilfs2/inode.c
index cf02f553071..689fb608648 100644
--- a/fs/nilfs2/inode.c
+++ b/fs/nilfs2/inode.c
@@ -25,7 +25,7 @@
 #include <linux/gfp.h>
 #include <linux/mpage.h>
 #include <linux/writeback.h>
-#include <linux/uio.h>
+#include <linux/aio.h>
 #include "nilfs.h"
 #include "btnode.h"
 #include "segment.h"
diff --git a/fs/ntfs/file.c b/fs/ntfs/file.c
index 1da4b81e6f7..c5670b8d198 100644
--- a/fs/ntfs/file.c
+++ b/fs/ntfs/file.c
@@ -27,6 +27,7 @@
 #include <linux/swap.h>
 #include <linux/uio.h>
 #include <linux/writeback.h>
+#include <linux/aio.h>
 
 #include <asm/page.h>
 #include <asm/uaccess.h>
diff --git a/fs/ntfs/inode.c b/fs/ntfs/inode.c
index d3e118cc6ff..2778b0255dc 100644
--- a/fs/ntfs/inode.c
+++ b/fs/ntfs/inode.c
@@ -28,6 +28,7 @@
 #include <linux/quotaops.h>
 #include <linux/slab.h>
 #include <linux/log2.h>
+#include <linux/aio.h>
 
 #include "aops.h"
 #include "attrib.h"
diff --git a/fs/ocfs2/aops.h b/fs/ocfs2/aops.h
index ffb2da370a9..f671e49beb3 100644
--- a/fs/ocfs2/aops.h
+++ b/fs/ocfs2/aops.h
@@ -22,6 +22,8 @@
 #ifndef OCFS2_AOPS_H
 #define OCFS2_AOPS_H
 
+#include <linux/aio.h>
+
 handle_t *ocfs2_start_walk_page_trans(struct inode *inode,
 							 struct page *page,
 							 unsigned from,
diff --git a/fs/ocfs2/dlmglue.c b/fs/ocfs2/dlmglue.c
index 12ae194ac94..3a44a648dae 100644
--- a/fs/ocfs2/dlmglue.c
+++ b/fs/ocfs2/dlmglue.c
@@ -2322,7 +2322,7 @@ int ocfs2_inode_lock_full_nested(struct inode *inode,
 	status = __ocfs2_cluster_lock(osb, lockres, level, dlm_flags,
 				      arg_flags, subclass, _RET_IP_);
 	if (status < 0) {
-		if (status != -EAGAIN && status != -EIOCBRETRY)
+		if (status != -EAGAIN)
 			mlog_errno(status);
 		goto bail;
 	}
diff --git a/fs/ocfs2/inode.h b/fs/ocfs2/inode.h
index 88924a3133f..621fc73bf23 100644
--- a/fs/ocfs2/inode.h
+++ b/fs/ocfs2/inode.h
@@ -147,8 +147,6 @@ void ocfs2_refresh_inode(struct inode *inode,
 int ocfs2_mark_inode_dirty(handle_t *handle,
 			   struct inode *inode,
 			   struct buffer_head *bh);
-int ocfs2_aio_read(struct file *file, struct kiocb *req, struct iocb *iocb);
-int ocfs2_aio_write(struct file *file, struct kiocb *req, struct iocb *iocb);
 struct buffer_head *ocfs2_bread(struct inode *inode,
 				int block, int *err, int reada);
 
diff --git a/fs/pipe.c b/fs/pipe.c
index a029a14bacf..d2c45e14e6d 100644
--- a/fs/pipe.c
+++ b/fs/pipe.c
@@ -21,6 +21,7 @@
 #include <linux/audit.h>
 #include <linux/syscalls.h>
 #include <linux/fcntl.h>
+#include <linux/aio.h>
 
 #include <asm/uaccess.h>
 #include <asm/ioctls.h>
diff --git a/fs/read_write.c b/fs/read_write.c
index 90ba3b350e5..03430008704 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -9,6 +9,7 @@
 #include <linux/fcntl.h>
 #include <linux/file.h>
 #include <linux/uio.h>
+#include <linux/aio.h>
 #include <linux/fsnotify.h>
 #include <linux/security.h>
 #include <linux/export.h>
@@ -329,16 +330,6 @@ int rw_verify_area(int read_write, struct file *file, loff_t *ppos, size_t count
 	return count > MAX_RW_COUNT ? MAX_RW_COUNT : count;
 }
 
-static void wait_on_retry_sync_kiocb(struct kiocb *iocb)
-{
-	set_current_state(TASK_UNINTERRUPTIBLE);
-	if (!kiocbIsKicked(iocb))
-		schedule();
-	else
-		kiocbClearKicked(iocb);
-	__set_current_state(TASK_RUNNING);
-}
-
 ssize_t do_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos)
 {
 	struct iovec iov = { .iov_base = buf, .iov_len = len };
@@ -350,13 +341,7 @@ ssize_t do_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *pp
 	kiocb.ki_left = len;
 	kiocb.ki_nbytes = len;
 
-	for (;;) {
-		ret = filp->f_op->aio_read(&kiocb, &iov, 1, kiocb.ki_pos);
-		if (ret != -EIOCBRETRY)
-			break;
-		wait_on_retry_sync_kiocb(&kiocb);
-	}
-
+	ret = filp->f_op->aio_read(&kiocb, &iov, 1, kiocb.ki_pos);
 	if (-EIOCBQUEUED == ret)
 		ret = wait_on_sync_kiocb(&kiocb);
 	*ppos = kiocb.ki_pos;
@@ -406,13 +391,7 @@ ssize_t do_sync_write(struct file *filp, const char __user *buf, size_t len, lof
 	kiocb.ki_left = len;
 	kiocb.ki_nbytes = len;
 
-	for (;;) {
-		ret = filp->f_op->aio_write(&kiocb, &iov, 1, kiocb.ki_pos);
-		if (ret != -EIOCBRETRY)
-			break;
-		wait_on_retry_sync_kiocb(&kiocb);
-	}
-
+	ret = filp->f_op->aio_write(&kiocb, &iov, 1, kiocb.ki_pos);
 	if (-EIOCBQUEUED == ret)
 		ret = wait_on_sync_kiocb(&kiocb);
 	*ppos = kiocb.ki_pos;
@@ -592,13 +571,7 @@ static ssize_t do_sync_readv_writev(struct file *filp, const struct iovec *iov,
 	kiocb.ki_left = len;
 	kiocb.ki_nbytes = len;
 
-	for (;;) {
-		ret = fn(&kiocb, iov, nr_segs, kiocb.ki_pos);
-		if (ret != -EIOCBRETRY)
-			break;
-		wait_on_retry_sync_kiocb(&kiocb);
-	}
-
+	ret = fn(&kiocb, iov, nr_segs, kiocb.ki_pos);
 	if (ret == -EIOCBQUEUED)
 		ret = wait_on_sync_kiocb(&kiocb);
 	*ppos = kiocb.ki_pos;
diff --git a/fs/reiserfs/inode.c b/fs/reiserfs/inode.c
index ea5061fd4f3..77d6d47abc8 100644
--- a/fs/reiserfs/inode.c
+++ b/fs/reiserfs/inode.c
@@ -18,6 +18,7 @@
 #include <linux/writeback.h>
 #include <linux/quotaops.h>
 #include <linux/swap.h>
+#include <linux/aio.h>
 
 int reiserfs_commit_write(struct file *f, struct page *page,
 			  unsigned from, unsigned to);
diff --git a/fs/ubifs/file.c b/fs/ubifs/file.c
index f12189d2db1..14374530784 100644
--- a/fs/ubifs/file.c
+++ b/fs/ubifs/file.c
@@ -50,6 +50,7 @@
  */
 
 #include "ubifs.h"
+#include <linux/aio.h>
 #include <linux/mount.h>
 #include <linux/namei.h>
 #include <linux/slab.h>
diff --git a/fs/udf/inode.c b/fs/udf/inode.c
index 7a12e48ad81..b6d15d34981 100644
--- a/fs/udf/inode.c
+++ b/fs/udf/inode.c
@@ -38,6 +38,7 @@
 #include <linux/slab.h>
 #include <linux/crc-itu-t.h>
 #include <linux/mpage.h>
+#include <linux/aio.h>
 
 #include "udf_i.h"
 #include "udf_sb.h"
diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c
index 3244c988d37..2b2691b7342 100644
--- a/fs/xfs/xfs_aops.c
+++ b/fs/xfs/xfs_aops.c
@@ -31,6 +31,7 @@
 #include "xfs_vnodeops.h"
 #include "xfs_trace.h"
 #include "xfs_bmap.h"
+#include <linux/aio.h>
 #include <linux/gfp.h>
 #include <linux/mpage.h>
 #include <linux/pagevec.h>
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index 054d60c0ac5..a5f2042aec8 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -36,6 +36,7 @@
 #include "xfs_ioctl.h"
 #include "xfs_trace.h"
 
+#include <linux/aio.h>
 #include <linux/dcache.h>
 #include <linux/falloc.h>
 #include <linux/pagevec.h>