On Tue, Apr 5, 2016 at 8:49 PM, Christoph Hellwig <hch@xxxxxxxxxxxxx> wrote: > On Tue, Apr 05, 2016 at 07:56:56PM +0800, Ming Lei wrote: >> diff --git a/drivers/md/bcache/io.c b/drivers/md/bcache/io.c >> index 86a0bb8..1c48462 100644 >> --- a/drivers/md/bcache/io.c >> +++ b/drivers/md/bcache/io.c >> @@ -26,8 +26,7 @@ struct bio *bch_bbio_alloc(struct cache_set *c) >> >> bio_init(bio); >> bio->bi_flags |= BIO_POOL_NONE << BIO_POOL_OFFSET; >> - bio->bi_max_vecs = bucket_pages(c); >> - bio->bi_io_vec = bio->bi_inline_vecs; >> + bio_set_vec_table(bio, bio->bi_inline_vecs, bucket_pages(c)); > > All this bcache code needs to move away from bio_init on a bio > embedded in a driver private structure toward properly using > bio_alloc / bio_alloc_bioset. That will also fix the crash > with bcache over md that Shaohua reported, so I'd suggest to fast > track this part of the series. I suggest to keep this usage for the following reasons: - bio can be embedded into one biger instance, which is often allocated dynamically, so one extra allocation for bio can be avoided. - we should support arbitrary bio size by this way, at least bio_add_page() supports this usage. Also code gets lots of simplication with arbitrary bio size support, such as prio_io(): bcache BTW, the root cause for bcache crash still isn't clear now because blk_bio_segment_split() should split big bio into proper size with all queue's limits. Maybe the max segment limit isn't figured out correctly. Thanks, Ming Lei -- To unsubscribe from this list: send the line "unsubscribe linux-block" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
