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author | Ratna Manoj Bolla <manoj.br@gmail.com> | 2017-03-24 14:08:29 -0400 |
---|---|---|
committer | Jens Axboe <axboe@fb.com> | 2017-03-24 15:42:47 -0600 |
commit | abbbdf12497d36b001e0865bc5bc6cc363f3a5e1 (patch) | |
tree | e0534687a8cf3b686bcff619320ec3258c8986bc /drivers/block/nbd.c | |
parent | f8586855031a1d6b243f013c3082631346fddfad (diff) | |
download | lwn-abbbdf12497d36b001e0865bc5bc6cc363f3a5e1.tar.gz lwn-abbbdf12497d36b001e0865bc5bc6cc363f3a5e1.zip |
nbd: replace kill_bdev() with __invalidate_device()
When a filesystem is mounted on a nbd device and on a disconnect, because
of kill_bdev(), and resetting bdev size to zero, buffer_head mappings are
getting destroyed under mounted filesystem.
After a bdev size reset(i.e bdev->bd_inode->i_size = 0) on a disconnect,
followed by a sys_umount(),
generic_shutdown_super()->...
->__sync_blockdev()->...
-blkdev_writepages()->...
->do_invalidatepage()->...
-discard_buffer() is discarding superblock buffer_head assumed
to be in mapped state by ext4_commit_super().
[mlin: ported to 4.11-rc2]
Signed-off-by: Ratna Manoj Bolla <manoj.br@gmail.com
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Diffstat (limited to 'drivers/block/nbd.c')
-rw-r--r-- | drivers/block/nbd.c | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c index b0003dab90b9..d8a23561b4cb 100644 --- a/drivers/block/nbd.c +++ b/drivers/block/nbd.c @@ -126,7 +126,8 @@ static const char *nbdcmd_to_ascii(int cmd) static int nbd_size_clear(struct nbd_device *nbd, struct block_device *bdev) { - bd_set_size(bdev, 0); + if (bdev->bd_openers <= 1) + bd_set_size(bdev, 0); set_capacity(nbd->disk, 0); kobject_uevent(&nbd_to_dev(nbd)->kobj, KOBJ_CHANGE); @@ -665,6 +666,8 @@ static void nbd_reset(struct nbd_device *nbd) static void nbd_bdev_reset(struct block_device *bdev) { + if (bdev->bd_openers > 1) + return; set_device_ro(bdev, false); bdev->bd_inode->i_size = 0; if (max_part > 0) { @@ -728,7 +731,8 @@ static int nbd_clear_sock(struct nbd_device *nbd, struct block_device *bdev) { sock_shutdown(nbd); nbd_clear_que(nbd); - kill_bdev(bdev); + + __invalidate_device(bdev, true); nbd_bdev_reset(bdev); /* * We want to give the run thread a chance to wait for everybody |