aio: add kiocb_cancel()

Minor refactoring, to get rid of some duplicated code [akpm@linux-foundation.org: fix warning] Signed-off-by: Kent Overstreet <koverstreet@google.com> Cc: Zach Brown <zab@redhat.com> Cc: Felipe Balbi <balbi@ti.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Jens Axboe <axboe@kernel.dk> Cc: Asai Thambi S P <asamymuthupa@micron.com> Cc: Selvan Mani <smani@micron.com> Cc: Sam Bradshaw <sbradshaw@micron.com> Acked-by: Jeff Moyer <jmoyer@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Benjamin LaHaise <bcrl@kvack.org> Reviewed-by: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

aio: add kiocb_cancel()
Minor refactoring, to get rid of some duplicated code [akpm@linux-foundation.org: fix warning] Signed-off-by: Kent Overstreet <koverstreet@google.com> Cc: Zach Brown <zab@redhat.com> Cc: Felipe Balbi <balbi@ti.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Jens Axboe <axboe@kernel.dk> Cc: Asai Thambi S P <asamymuthupa@micron.com> Cc: Selvan Mani <smani@micron.com> Cc: Sam Bradshaw <sbradshaw@micron.com> Acked-by: Jeff Moyer <jmoyer@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Benjamin LaHaise <bcrl@kvack.org> Reviewed-by: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Kent Overstreet · Linus Torvalds
1 parent 2d68449e86
Showing 1 changed file with 43 additions and 36 deletions Side-by-side Diff
fs/aio.c
@@ -220,6 +220,29 @@
 		__put_ioctx(kioctx);
 }
  
+static int kiocb_cancel(struct kioctx *ctx, struct kiocb *kiocb,
+			struct io_event *res)
+{
+	int (*cancel)(struct kiocb *, struct io_event *);
+	int ret = -EINVAL;
+
+	cancel = kiocb->ki_cancel;
+	kiocbSetCancelled(kiocb);
+	if (cancel) {
+		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;
+}
+
 /* ioctx_alloc
  *	Allocates and initializes an ioctx.  Returns an ERR_PTR if it failed.
  */
  
  
@@ -290,25 +313,19 @@
  */
 static void kill_ctx(struct kioctx *ctx)
 {
-	int (*cancel)(struct kiocb *, struct io_event *);
 	struct task_struct *tsk = current;
 	DECLARE_WAITQUEUE(wait, tsk);
 	struct io_event res;
+	struct kiocb *req;
  
 	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);
-		}
+		req = list_first_entry(&ctx->active_reqs,
+					struct kiocb, ki_list);
+
+		list_del_init(&req->ki_list);
+		kiocb_cancel(ctx, req, &res);
 	}
  
 	if (!ctx->reqs_active)
@@ -1416,7 +1433,7 @@
 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;
  
  
@@ -1431,32 +1448,22 @@
 		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);
...	...	@@ -220,6 +220,29 @@
220	220	__put_ioctx(kioctx);
221	221	}
222	222
	223	+static int kiocb_cancel(struct kioctx ctx, struct kiocb kiocb,
	224	+ struct io_event *res)
	225	+{
	226	+ int (cancel)(struct kiocb , struct io_event *);
	227	+ int ret = -EINVAL;
	228	+
	229	+ cancel = kiocb->ki_cancel;
	230	+ kiocbSetCancelled(kiocb);
	231	+ if (cancel) {
	232	+ kiocb->ki_users++;
	233	+ spin_unlock_irq(&ctx->ctx_lock);
	234	+
	235	+ memset(res, 0, sizeof(*res));
	236	+ res->obj = (u64)(unsigned long)kiocb->ki_obj.user;
	237	+ res->data = kiocb->ki_user_data;
	238	+ ret = cancel(kiocb, res);
	239	+
	240	+ spin_lock_irq(&ctx->ctx_lock);
	241	+ }
	242	+
	243	+ return ret;
	244	+}
	245	+
223	246	/* ioctx_alloc
224	247	* Allocates and initializes an ioctx. Returns an ERR_PTR if it failed.
225	248	*/
226	249
227	250
...	...	@@ -290,25 +313,19 @@
290	313	*/
291	314	static void kill_ctx(struct kioctx *ctx)
292	315	{
293		- int (cancel)(struct kiocb , struct io_event *);
294	316	struct task_struct *tsk = current;
295	317	DECLARE_WAITQUEUE(wait, tsk);
296	318	struct io_event res;
	319	+ struct kiocb *req;
297	320
298	321	spin_lock_irq(&ctx->ctx_lock);
299	322	ctx->dead = 1;
300	323	while (!list_empty(&ctx->active_reqs)) {
301		- struct list_head *pos = ctx->active_reqs.next;
302		- struct kiocb *iocb = list_kiocb(pos);
303		- list_del_init(&iocb->ki_list);
304		- cancel = iocb->ki_cancel;
305		- kiocbSetCancelled(iocb);
306		- if (cancel) {
307		- iocb->ki_users++;
308		- spin_unlock_irq(&ctx->ctx_lock);
309		- cancel(iocb, &res);
310		- spin_lock_irq(&ctx->ctx_lock);
311		- }
	324	+ req = list_first_entry(&ctx->active_reqs,
	325	+ struct kiocb, ki_list);
	326	+
	327	+ list_del_init(&req->ki_list);
	328	+ kiocb_cancel(ctx, req, &res);
312	329	}
313	330
314	331	if (!ctx->reqs_active)
...	...	@@ -1416,7 +1433,7 @@
1416	1433	SYSCALL_DEFINE3(io_cancel, aio_context_t, ctx_id, struct iocb __user *, iocb,
1417	1434	struct io_event __user *, result)
1418	1435	{
1419		- int (cancel)(struct kiocb iocb, struct io_event *res);
	1436	+ struct io_event res;
1420	1437	struct kioctx *ctx;
1421	1438	struct kiocb *kiocb;
1422	1439	u32 key;
1423	1440
1424	1441
...	...	@@ -1431,32 +1448,22 @@
1431	1448	return -EINVAL;
1432	1449
1433	1450	spin_lock_irq(&ctx->ctx_lock);
1434		- ret = -EAGAIN;
	1451	+
1435	1452	kiocb = lookup_kiocb(ctx, iocb, key);
1436		- if (kiocb && kiocb->ki_cancel) {
1437		- cancel = kiocb->ki_cancel;
1438		- kiocb->ki_users ++;
1439		- kiocbSetCancelled(kiocb);
1440		- } else
1441		- cancel = NULL;
	1453	+ if (kiocb)
	1454	+ ret = kiocb_cancel(ctx, kiocb, &res);
	1455	+ else
	1456	+ ret = -EINVAL;
	1457	+
1442	1458	spin_unlock_irq(&ctx->ctx_lock);
1443	1459
1444		- if (NULL != cancel) {
1445		- struct io_event tmp;
1446		- pr_debug("calling cancel\n");
1447		- memset(&tmp, 0, sizeof(tmp));
1448		- tmp.obj = (u64)(unsigned long)kiocb->ki_obj.user;
1449		- tmp.data = kiocb->ki_user_data;
1450		- ret = cancel(kiocb, &tmp);
1451		- if (!ret) {
1452		- /* Cancellation succeeded -- copy the result
1453		- * into the user's buffer.
1454		- */
1455		- if (copy_to_user(result, &tmp, sizeof(tmp)))
1456		- ret = -EFAULT;
1457		- }
1458		- } else
1459		- ret = -EINVAL;
	1460	+ if (!ret) {
	1461	+ /* Cancellation succeeded -- copy the result
	1462	+ * into the user's buffer.
	1463	+ */
	1464	+ if (copy_to_user(result, &res, sizeof(res)))
	1465	+ ret = -EFAULT;
	1466	+ }
1460	1467
1461	1468	put_ioctx(ctx);
1462	1469