summaryrefslogtreecommitdiffstats
path: root/drivers/block/rbd.c
diff options
context:
space:
mode:
authorIlya Dryomov <idryomov@gmail.com>2017-10-12 12:35:19 +0200
committerIlya Dryomov <idryomov@gmail.com>2017-11-13 12:11:41 +0100
commit1de797bb248d2276337139fecaffbd3bbc0f736d (patch)
treec8ee0b09435866327547ce07b5603346588e079a /drivers/block/rbd.c
parentbb0581f01c38ff525295fc6128bc3a49202dabae (diff)
downloadlinux-1de797bb248d2276337139fecaffbd3bbc0f736d.tar.bz2
rbd: fix and simplify rbd_ioctl_set_ro()
->open_count/-EBUSY check is bogus and wrong: when an open device is set read-only, blkdev_write_iter() refuses further writes with -EPERM. This is standard behaviour and all other block devices allow this. set_disk_ro() call is also problematic: we affect the entire device when called on a single partition. All rbd_ioctl_set_ro() needs to do is refuse ro -> rw transition for mapped snapshots. Everything else can be handled by generic code. Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Diffstat (limited to 'drivers/block/rbd.c')
-rw-r--r--drivers/block/rbd.c34
1 files changed, 6 insertions, 28 deletions
diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index adc877dfef5c..fb7cb38a6d83 100644
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -640,46 +640,24 @@ static void rbd_release(struct gendisk *disk, fmode_t mode)
static int rbd_ioctl_set_ro(struct rbd_device *rbd_dev, unsigned long arg)
{
- int ret = 0;
- int val;
- bool ro;
- bool ro_changed = false;
+ int ro;
- /* get_user() may sleep, so call it before taking rbd_dev->lock */
- if (get_user(val, (int __user *)(arg)))
+ if (get_user(ro, (int __user *)arg))
return -EFAULT;
- ro = val ? true : false;
- /* Snapshot doesn't allow to write*/
+ /* Snapshots can't be marked read-write */
if (rbd_dev->spec->snap_id != CEPH_NOSNAP && !ro)
return -EROFS;
- spin_lock_irq(&rbd_dev->lock);
- /* prevent others open this device */
- if (rbd_dev->open_count > 1) {
- ret = -EBUSY;
- goto out;
- }
-
- if (rbd_dev->mapping.read_only != ro) {
- rbd_dev->mapping.read_only = ro;
- ro_changed = true;
- }
-
-out:
- spin_unlock_irq(&rbd_dev->lock);
- /* set_disk_ro() may sleep, so call it after releasing rbd_dev->lock */
- if (ret == 0 && ro_changed)
- set_disk_ro(rbd_dev->disk, ro ? 1 : 0);
-
- return ret;
+ /* Let blkdev_roset() handle it */
+ return -ENOTTY;
}
static int rbd_ioctl(struct block_device *bdev, fmode_t mode,
unsigned int cmd, unsigned long arg)
{
struct rbd_device *rbd_dev = bdev->bd_disk->private_data;
- int ret = 0;
+ int ret;
switch (cmd) {
case BLKROSET: