On Mon, Jul 30, 2012 at 03:14:28PM +0800, majianpeng wrote: > When exec bio_alloc, the bi_rw is zero.But after calling bio_add_page,
What about submit_bio? That sets the bi_rw as well? > it will use bi_rw. > Fox example, in functiion __bio_add_page,it will call merge_bvec_fn(). function. > The merge_bvec_fn of raid456 will use the bi_rw to judge the merge. > >> if ((bvm->bi_rw & 1) == WRITE) > >> return biovec->bv_len; /* always allow writes to be mergeable */ So what does that mean? Without this patch what happens? > > > Jianpeng Ma (8): Can you collapse all of this in just one patch? > Evalue bio->bi_rw after calling bio_alloc() and before calling It is 'evaluate' > bio_add_page(). > Evalue bio->bi_rw after calling bio_alloc() and before calling > bio_add_page(). > Evalue bio->bi_rw after calling bio_alloc() and before calling > bio_add_page(). > Evalue bio->bi_rw after calling bio_alloc() and before calling > bio_add_page(). > Evalue bio->bi_rw after calling bio_alloc() and before calling > bio_add_page(). > Evalue bio->bi_rw after calling bio_alloc() and before calling > bio_add_page(). > Evalue bio->bi_rw after calling bio_alloc() and before calling > bio_add_page(). > Evalue bio->bi_rw after calling bio_alloc() and before calling > bio_add_page(). > > block/blk-lib.c | 1 + > drivers/block/xen-blkback/blkback.c | 1 + I am not really sure if that is correct. Does 'submit_bio' not do the job properly? > fs/btrfs/check-integrity.c | 1 + > fs/direct-io.c | 1 + > fs/ext4/page-io.c | 1 + > fs/jfs/jfs_metapage.c | 1 + > fs/ocfs2/cluster/heartbeat.c | 8 +++++--- > fs/xfs/xfs_aops.c | 2 ++ > fs/xfs/xfs_buf.c | 1 + > 9 files changed, 14 insertions(+), 3 deletions(-) > > -- > 1.7.9.5 ------------------------------------------------------------------------------ Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ _______________________________________________ Jfs-discussion mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/jfs-discussion
