tree 90b902fe8797c11d4f76d08353e44bbf82a850e1
parent aa8b57aa3d1c06ca53312294ee6dfc767ee3ddb3
author Kent Overstreet <koverstreet@google.com> 1346797238 -0700
committer Kent Overstreet <koverstreet@google.com> 1364073330 -0700

block: Change bio_split() to respect the current value of bi_idx

In the current code bio_split() won't be seeing partially completed bios
so this doesn't change any behaviour, but this makes the code a bit
clearer as to what bio_split() actually requires.

The immediate purpose of the patch is removing unnecessary bi_idx
references, but the end goal is to allow partial completed bios to be
submitted, which along with immutable biovecs enables effecient bio
splitting.

Some of the callers were (double) checking that bios could be split, so
update their checks too.

Signed-off-by: Kent Overstreet <koverstreet@google.com>
CC: Jens Axboe <axboe@kernel.dk>
CC: Lars Ellenberg <drbd-dev@lists.linbit.com>
CC: Neil Brown <neilb@suse.de>
CC: Martin K. Petersen <martin.petersen@oracle.com>