On Tue, May 02, 2017 at 01:42:24PM +1000, NeilBrown wrote:

"flags" arguments are often seen as good API design as they allow
easy extensibility.
bioset_create_nobvec() is implemented internally as a variation in
flags passed to __bioset_create().

From driver's view, this flag has document benifit too.

To support future extension, make the internal structure part of the
API.
i.e. add a 'flags' argument to bioset_create() and discard
bioset_create_nobvec().

Note that the bio_split allocations in drivers/md/raid* do not need
the bvec mempool - they should have used bioset_create_nobvec().

Suggested-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: NeilBrown <redacted>

Reviewed-by: Ming Lei <redacted>

Thanks,
Ming