On Wed, Nov 21, 2018 at 02:59:08PM +0100, Christoph Hellwig wrote:

bio_readpage_error currently uses bi_vcnt to decide if it is worth
retrying an I/O.  But the vector count is mostly an implementation
artifact - it really should figure out if there is more than a
single sector worth retrying.  Use bi_size for that and shift by
PAGE_SHIFT.  This really should be blocks/sectors, but given that
btrfs doesn't support a sector size different from the PAGE_SIZE
using the page size keeps the changes to a minimum.

Signed-off-by: Christoph Hellwig <hch@lst.de>

Reviewed-by: David Sterba <dsterba@suse.com>