Hi Guys, It is always not a good practice to access bio->bi_vcnt and bio->bi_io_vec from drivers directly. Also this kind of direct access will cause trouble when converting to multipage bvecs. The 1st patch introduces the following 4 bio helpers which can be used inside drivers for avoiding direct access to .bi_vcnt and .bi_io_vec. bio_pages() bio_is_full() bio_get_base_vec() bio_set_vec_table() Both bio_pages() and bio_is_full() can be easy to convert to multipage bvecs. For bio_get_base_vec() and bio_set_vec_table(), they are often used during initializing a new bio or in case of single bvec bio. With the two new helpers, it becomes quite easy to audit access to .bi_io_vec and .bi_vcnt. Most of the other patches use the 4 helpers to clean up most of direct access to .bi_vcnt and .bi_io_vec from drivers, except for MD and btrfs, which two subsystems will be done in the future. Also bio_add_page() is used in floppy, dm-crypt and fs/logfs to avoiding direct access to .bi_vcnt & .bi_io_vec. Thanks, Ming Ming Lei (27): block: bio: introduce 4 helpers for cleanup block: drbd: use bio_get_base_vec() to retrieve the 1st bvec block: drbd: remove impossible failure handling block: loop: use bio_get_base_vec() to retrive bvec table block: pktcdvd: use bio_get_base_vec() to retrive bvec table block: floppy: use bio_set_vec_table() block: floppy: use bio_add_page() staging: lustre: avoid to use bio->bi_vcnt directly target: use bio_is_full() bcache: debug: avoid to access .bi_io_vec directly bcache: io.c: use bio_set_vec_table bcache: journal.c: use bio_set_vec_table() bcache: movinggc: use bio_set_vec_table() bcache: writeback: use bio_set_vec_table() bcache: super: use bio_set_vec_table() bcache: super: use bio_get_base_vec dm: crypt: use bio_add_page() dm: dm-io.c: use bio_get_base_vec() dm: dm.c: replace 'bio->bi_vcnt == 1' with !bio_multiple_segments dm: dm-bufio.c: use bio_set_vec_table() fs: logfs: use bio_set_vec_table() fs: logfs: convert to bio_add_page() in sync_request() fs: logfs: use bio_add_page() in __bdev_writeseg() fs: logfs: use bio_add_page() in do_erase() fs: logfs: remove unnecesary check kernel/power/swap.c: use bio_get_base_vec() mm: page_io.c: use bio_get_base_vec() drivers/block/drbd/drbd_bitmap.c | 4 +- drivers/block/drbd/drbd_receiver.c | 14 +--- drivers/block/floppy.c | 9 +-- drivers/block/loop.c | 5 +- drivers/block/pktcdvd.c | 3 +- drivers/md/bcache/debug.c | 11 ++- drivers/md/bcache/io.c | 3 +- drivers/md/bcache/journal.c | 3 +- drivers/md/bcache/movinggc.c | 6 +- drivers/md/bcache/super.c | 28 +++++--- drivers/md/bcache/writeback.c | 4 +- drivers/md/dm-bufio.c | 3 +- drivers/md/dm-crypt.c | 8 +-- drivers/md/dm-io.c | 7 +- drivers/md/dm.c | 3 +- drivers/staging/lustre/lustre/llite/lloop.c | 9 +-- drivers/target/target_core_pscsi.c | 2 +- fs/logfs/dev_bdev.c | 107 +++++++++++----------------- include/linux/bio.h | 28 ++++++++ kernel/power/swap.c | 10 ++- mm/page_io.c | 18 ++++- 21 files changed, 156 insertions(+), 129 deletions(-) -- 1.9.1 -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel