From: Alessio Balsini <bals...@android.com>
[ Upstream commit fdbe4eeeb1aac219b14f10c0ed31ae5d1123e9b8 ]
Enabling Direct I/O with loop devices helps reducing memory usage by
avoiding double caching. 32 bit applications running on 64 bits systems
are currently not able to request direct I/O because is missing from the
lo_compat_ioctl.
This patch fixes the compatibility issue mentioned above by exporting
LOOP_SET_DIRECT_IO as additional lo_compat_ioctl() entry.
The input argument for this ioctl is a single long converted to a 1-bit
boolean, so compatibility is preserved.
Cc: Jens Axboe <ax...@kernel.dk>
Signed-off-by: Alessio Balsini <bals...@android.com>
Signed-off-by: Jens Axboe <ax...@kernel.dk>
Signed-off-by: Sasha Levin <sas...@kernel.org>
---
drivers/block/loop.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index cef8e00c9d9d6..126c2c5146732 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -1719,6 +1719,7 @@ static int lo_compat_ioctl(struct block_device *bdev,
fmode_t mode,
case LOOP_SET_FD:
case LOOP_CHANGE_FD:
case LOOP_SET_BLOCK_SIZE:
+ case LOOP_SET_DIRECT_IO:
err = lo_ioctl(bdev, mode, cmd, arg);
break;
default:
--
2.20.1
