Commit 23c560a9 authored Apr 15, 2009 by Tejun Heo Committed by Jens Axboe Apr 22, 2009

scatterlist: make sure sg_miter_next() doesn't return 0 sized mappings



Impact: fix not-so-critical but annoying bug

sg_miter_next() returns 0 sized mapping if there is an zero sized sg
entry in the list or at the end of each iteration.  As the users
always check the ->length field, this bug shouldn't be critical other
than causing unnecessary iteration.

Fix it.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

parent 09106974

lib/scatterlist.c

+6 −3

Original line number	Diff line number	Diff line
		@@ -347,9 +347,12 @@ bool sg_miter_next(struct sg_mapping_iter *miter)
		sg_miter_stop(miter);

		/* get to the next sg if necessary. __offset is adjusted by stop */
		if (miter->__offset == miter->__sg->length && --miter->__nents) {
		while (miter->__offset == miter->__sg->length) {
		if (--miter->__nents) {
		miter->__sg = sg_next(miter->__sg);
		miter->__offset = 0;
		} else
		return false;
		}

		/* map the next page */