On 1/26/21 3:33 AM, Qu Wenruo wrote:

For the incoming subpage support, UNMAPPED extent buffer will have
different behavior in btrfs_release_extent_buffer().

This means we need to set UNMAPPED bit early before calling
btrfs_release_extent_buffer().

Currently there is only one caller which relies on
btrfs_release_extent_buffer() in its error path while set UNMAPPED bit
late:
- btrfs_clone_extent_buffer()

Make it subpage compatible by setting the UNMAPPED bit early, since
we're here, also move the UPTODATE bit early.

There is another caller, __alloc_dummy_extent_buffer(), setting UNAMPPED
bit late, but that function clean up the allocated page manually, thus
no need for any modification.

Signed-off-by: Qu Wenruo <redacted>

Reviewed-by: Josef Bacik <josef@toxicpanda.com>

Thanks,

Josef