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-rw-r--r--fs/aio.c65
1 files changed, 36 insertions, 29 deletions
diff --git a/fs/aio.c b/fs/aio.c
index 78c514cfd21..5b600cb8779 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -160,7 +160,7 @@ static int aio_setup_ring(struct kioctx *ctx)
info->nr = nr_events; /* trusted copy */
- ring = kmap_atomic(info->ring_pages[0], KM_USER0);
+ ring = kmap_atomic(info->ring_pages[0]);
ring->nr = nr_events; /* user copy */
ring->id = ctx->user_id;
ring->head = ring->tail = 0;
@@ -168,32 +168,32 @@ static int aio_setup_ring(struct kioctx *ctx)
ring->compat_features = AIO_RING_COMPAT_FEATURES;
ring->incompat_features = AIO_RING_INCOMPAT_FEATURES;
ring->header_length = sizeof(struct aio_ring);
- kunmap_atomic(ring, KM_USER0);
+ kunmap_atomic(ring);
return 0;
}
/* aio_ring_event: returns a pointer to the event at the given index from
- * kmap_atomic(, km). Release the pointer with put_aio_ring_event();
+ * 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, km) ({ \
+#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], km); \
+ (info)->ring_pages[pos / AIO_EVENTS_PER_PAGE]); \
__event += pos % AIO_EVENTS_PER_PAGE; \
__event; \
})
-#define put_aio_ring_event(event, km) do { \
+#define put_aio_ring_event(event) do { \
struct io_event *__event = (event); \
(void)__event; \
- kunmap_atomic((void *)((unsigned long)__event & PAGE_MASK), km); \
+ kunmap_atomic((void *)((unsigned long)__event & PAGE_MASK)); \
} while(0)
static void ctx_rcu_free(struct rcu_head *head)
@@ -228,12 +228,6 @@ static void __put_ioctx(struct kioctx *ctx)
call_rcu(&ctx->rcu_head, ctx_rcu_free);
}
-static inline void get_ioctx(struct kioctx *kioctx)
-{
- BUG_ON(atomic_read(&kioctx->users) <= 0);
- atomic_inc(&kioctx->users);
-}
-
static inline int try_get_ioctx(struct kioctx *kioctx)
{
return atomic_inc_not_zero(&kioctx->users);
@@ -273,7 +267,7 @@ static struct kioctx *ioctx_alloc(unsigned nr_events)
mm = ctx->mm = current->mm;
atomic_inc(&mm->mm_count);
- atomic_set(&ctx->users, 1);
+ atomic_set(&ctx->users, 2);
spin_lock_init(&ctx->ctx_lock);
spin_lock_init(&ctx->ring_info.ring_lock);
init_waitqueue_head(&ctx->wait);
@@ -476,14 +470,23 @@ static void kiocb_batch_init(struct kiocb_batch *batch, long total)
batch->count = total;
}
-static void kiocb_batch_free(struct kiocb_batch *batch)
+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);
}
/*
@@ -600,11 +603,16 @@ static void aio_fput_routine(struct work_struct *data)
fput(req->ki_filp);
/* Link the iocb into the context's free list */
+ rcu_read_lock();
spin_lock_irq(&ctx->ctx_lock);
really_put_req(ctx, req);
+ /*
+ * at that point ctx might've been killed, but actual
+ * freeing is RCU'd
+ */
spin_unlock_irq(&ctx->ctx_lock);
+ rcu_read_unlock();
- put_ioctx(ctx);
spin_lock_irq(&fput_lock);
}
spin_unlock_irq(&fput_lock);
@@ -635,7 +643,6 @@ static int __aio_put_req(struct kioctx *ctx, struct kiocb *req)
* this function will be executed w/out any aio kthread wakeup.
*/
if (unlikely(!fput_atomic(req->ki_filp))) {
- get_ioctx(ctx);
spin_lock(&fput_lock);
list_add(&req->ki_list, &fput_head);
spin_unlock(&fput_lock);
@@ -1012,10 +1019,10 @@ int aio_complete(struct kiocb *iocb, long res, long res2)
if (kiocbIsCancelled(iocb))
goto put_rq;
- ring = kmap_atomic(info->ring_pages[0], KM_IRQ1);
+ ring = kmap_atomic(info->ring_pages[0]);
tail = info->tail;
- event = aio_ring_event(info, tail, KM_IRQ0);
+ event = aio_ring_event(info, tail);
if (++tail >= info->nr)
tail = 0;
@@ -1036,8 +1043,8 @@ int aio_complete(struct kiocb *iocb, long res, long res2)
info->tail = tail;
ring->tail = tail;
- put_aio_ring_event(event, KM_IRQ0);
- kunmap_atomic(ring, KM_IRQ1);
+ put_aio_ring_event(event);
+ kunmap_atomic(ring);
pr_debug("added to ring %p at [%lu]\n", iocb, tail);
@@ -1082,7 +1089,7 @@ static int aio_read_evt(struct kioctx *ioctx, struct io_event *ent)
unsigned long head;
int ret = 0;
- ring = kmap_atomic(info->ring_pages[0], KM_USER0);
+ 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);
@@ -1094,18 +1101,18 @@ static int aio_read_evt(struct kioctx *ioctx, struct io_event *ent)
head = ring->head % info->nr;
if (head != ring->tail) {
- struct io_event *evp = aio_ring_event(info, head, KM_USER1);
+ 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, KM_USER1);
+ put_aio_ring_event(evp);
}
spin_unlock(&info->ring_lock);
out:
- kunmap_atomic(ring, KM_USER0);
+ kunmap_atomic(ring);
dprintk("leaving aio_read_evt: %d h%lu t%lu\n", ret,
(unsigned long)ring->head, (unsigned long)ring->tail);
return ret;
@@ -1329,10 +1336,10 @@ SYSCALL_DEFINE2(io_setup, unsigned, nr_events, aio_context_t __user *, ctxp)
ret = PTR_ERR(ioctx);
if (!IS_ERR(ioctx)) {
ret = put_user(ioctx->user_id, ctxp);
- if (!ret)
+ if (!ret) {
+ put_ioctx(ioctx);
return 0;
-
- get_ioctx(ioctx); /* io_destroy() expects us to hold a ref */
+ }
io_destroy(ioctx);
}
@@ -1742,7 +1749,7 @@ long do_io_submit(aio_context_t ctx_id, long nr,
}
blk_finish_plug(&plug);
- kiocb_batch_free(&batch);
+ kiocb_batch_free(ctx, &batch);
put_ioctx(ctx);
return i ? i : ret;
}