[PATCH 3/4] erofs: specify accurate nr_iovecs for compressed bios

[Gao Xiang]

On Fri, Sep 18, 2020 at 09:54:35PM +0800, Gao Xiang wrote:
> Use more accurate compressed page count
> instead of BIO_MAX_PAGES unconditionally.
> 
> Signed-off-by: Gao Xiang <hsiangkao at redhat.com>

Found by ro_fsstress, the submission chain could be extended
by other threads, so this patch wouldn't work with the tail
merging strategy. Please ignore this and I will drop it and
send the next version instead.

Thanks,
Gao Xiang