1 files changed, 39 insertions, 28 deletions

diff --git a/fs/aio.c b/fs/aio.c
index ae94e1dea266..81c01290939b 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -191,6 +191,43 @@ static int aio_setup_ring(struct kioctx *ctx)
         kunmap_atomic((void *)((unsigned long)__event & PAGE_MASK), km); \
 } while(0)
 
+
+/* __put_ioctx
+ *      Called when the last user of an aio context has gone away,
+ *      and the struct needs to be freed.
+ */
+static void __put_ioctx(struct kioctx *ctx)
+{
+        unsigned nr_events = ctx->max_reqs;
+
+        BUG_ON(ctx->reqs_active);
+
+        cancel_delayed_work(&ctx->wq);
+        cancel_work_sync(&ctx->wq.work);
+        aio_free_ring(ctx);
+        mmdrop(ctx->mm);
+        ctx->mm = NULL;
+        pr_debug("__put_ioctx: freeing %p\n", ctx);
+        kmem_cache_free(kioctx_cachep, ctx);
+
+        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);
+        }
+}
+
+#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)
+
 /* ioctx_alloc
  *      Allocates and initializes an ioctx.  Returns an ERR_PTR if it failed.
  */
@@ -361,32 +398,6 @@ void exit_aio(struct mm_struct *mm)
         }
 }
 
-/* __put_ioctx
- *      Called when the last user of an aio context has gone away,
- *      and the struct needs to be freed.
- */
-void __put_ioctx(struct kioctx *ctx)
-{
-        unsigned nr_events = ctx->max_reqs;
-
-        BUG_ON(ctx->reqs_active);
-
-        cancel_delayed_work(&ctx->wq);
-        cancel_work_sync(&ctx->wq.work);
-        aio_free_ring(ctx);
-        mmdrop(ctx->mm);
-        ctx->mm = NULL;
-        pr_debug("__put_ioctx: freeing %p\n", ctx);
-        kmem_cache_free(kioctx_cachep, ctx);
-
-        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);
-        }
-}
-
 /* aio_get_req
  *      Allocate a slot for an aio request.  Increments the users count
  * of the kioctx so that the kioctx stays around until all requests are
@@ -545,7 +556,7 @@ int aio_put_req(struct kiocb *req)
 /*      Lookup an ioctx id.  ioctx_list is lockless for reads.
  *      FIXME: this is O(n) and is only suitable for development.
  */
-struct kioctx *lookup_ioctx(unsigned long ctx_id)
+static struct kioctx *lookup_ioctx(unsigned long ctx_id)
 {
         struct kioctx *ioctx;
         struct mm_struct *mm;
@@ -1552,7 +1563,7 @@ static int aio_wake_function(wait_queue_t *wait, unsigned mode,
         return 1;
 }
 
-int io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb,
+static int io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb,
                          struct iocb *iocb)
 {
         struct kiocb *req;