p71924506
/
linux_old1
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

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>
This commit is contained in:
Ratna Manoj Bolla 2017-03-24 14:08:29 -04:00 committed by Jens Axboe
parent f858685503
commit abbbdf1249
1 changed files with 6 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
drivers/block/nbd.c
View File

@ -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