btrfs: use device_list_mutex when removing stale devices

[ Upstream commit 7bcb8164ad9435068d9bc3b83b8a002c64d63ff6 ]

btrfs_free_stale_devices() finds a stale (not opened) device matching
path in the fs_uuid list. We are already under uuid_mutex so when we
check for each fs_devices, hold the device_list_mutex too.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Anand Jain 2018-05-29 17:23:20 +08:00 committed by Greg Kroah-Hartman
parent b57a7b0d41
commit 40ce21951a

View File

@ -640,8 +640,11 @@ static void btrfs_free_stale_devices(const char *path,
struct btrfs_device *device, *tmp_device;
list_for_each_entry_safe(fs_devices, tmp_fs_devices, &fs_uuids, fs_list) {
if (fs_devices->opened)
mutex_lock(&fs_devices->device_list_mutex);
if (fs_devices->opened) {
mutex_unlock(&fs_devices->device_list_mutex);
continue;
}
list_for_each_entry_safe(device, tmp_device,
&fs_devices->devices, dev_list) {
@ -661,16 +664,18 @@ static void btrfs_free_stale_devices(const char *path,
continue;
/* delete the stale device */
if (fs_devices->num_devices == 1) {
btrfs_sysfs_remove_fsid(fs_devices);
list_del(&fs_devices->fs_list);
free_fs_devices(fs_devices);
fs_devices->num_devices--;
list_del(&device->dev_list);
btrfs_free_device(device);
if (fs_devices->num_devices == 0)
break;
} else {
fs_devices->num_devices--;
list_del(&device->dev_list);
btrfs_free_device(device);
}
}
mutex_unlock(&fs_devices->device_list_mutex);
if (fs_devices->num_devices == 0) {
btrfs_sysfs_remove_fsid(fs_devices);
list_del(&fs_devices->fs_list);
free_fs_devices(fs_devices);
}
}
}