Btrfs: fix unprotected device's variants on 32bits machine
->total_bytes,->disk_total_bytes,->bytes_used is protected by chunk
lock when we change them, but sometimes we read them without any lock,
and we might get unexpected value. We fix this problem like inode's
i_size.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index f60d1ca..0ff2127 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -1553,7 +1553,7 @@
goto out_free;
}
- old_size = device->total_bytes;
+ old_size = btrfs_device_get_total_bytes(device);
if (mod < 0) {
if (new_size > old_size) {
@@ -2740,8 +2740,8 @@
}
di_args->devid = dev->devid;
- di_args->bytes_used = dev->bytes_used;
- di_args->total_bytes = dev->total_bytes;
+ di_args->bytes_used = btrfs_device_get_bytes_used(dev);
+ di_args->total_bytes = btrfs_device_get_total_bytes(dev);
memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
if (dev->name) {
struct rcu_string *name;