[LU-1693] filter_do_bio() and osd_do_bio() should set bi_rw before calling bio_add_page()

Sat, 22 Dec 2012 10:47:11 +0000

filter_do_bio() calls bio_add_page() without setting the direction of the bio. In bio_add_page() the direction is passed on to the merge_bvec_fn() if defined. raid5_mergeable_bvec() does check the direction and setting it correctly improves write bandwidth by allowing for full stripe writes.

I assume that this is equally true of osd_do_bio().

Whamcloud Community JIRA

[LU-1693] filter_do_bio() and osd_do_bio() should set bi_rw before calling bio_add_page()