diff options
| -rw-r--r-- | drivers/block/loop.c | 19 | ||||
| -rw-r--r-- | include/uapi/linux/loop.h | 1 |
2 files changed, 20 insertions, 0 deletions
diff --git a/drivers/block/loop.c b/drivers/block/loop.c index 06cad7edc0d3..75db3b98ec2b 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -1228,6 +1228,20 @@ static int loop_set_capacity(struct loop_device *lo, struct block_device *bdev) return figure_loop_size(lo, lo->lo_offset, lo->lo_sizelimit); } +static int loop_set_dio(struct loop_device *lo, unsigned long arg) +{ + int error = -ENXIO; + if (lo->lo_state != Lo_bound) + goto out; + + __loop_update_dio(lo, !!arg); + if (lo->use_dio == !!arg) + return 0; + error = -EINVAL; + out: + return error; +} + static int lo_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd, unsigned long arg) { @@ -1271,6 +1285,11 @@ static int lo_ioctl(struct block_device *bdev, fmode_t mode, if ((mode & FMODE_WRITE) || capable(CAP_SYS_ADMIN)) err = loop_set_capacity(lo, bdev); break; + case LOOP_SET_DIRECT_IO: + err = -EPERM; + if ((mode & FMODE_WRITE) || capable(CAP_SYS_ADMIN)) + err = loop_set_dio(lo, arg); + break; default: err = lo->ioctl ? lo->ioctl(lo, cmd, arg) : -EINVAL; } diff --git a/include/uapi/linux/loop.h b/include/uapi/linux/loop.h index 949851ce681f..c8125ec1f4f2 100644 --- a/include/uapi/linux/loop.h +++ b/include/uapi/linux/loop.h @@ -87,6 +87,7 @@ struct loop_info64 { #define LOOP_GET_STATUS64 0x4C05 #define LOOP_CHANGE_FD 0x4C06 #define LOOP_SET_CAPACITY 0x4C07 +#define LOOP_SET_DIRECT_IO 0x4C08 /* /dev/loop-control interface */ #define LOOP_CTL_ADD 0x4C80 |