[PATCH v2 0/8] Add support for segments smaller than one page

Bart Van Assche
2022-11-23T20:58:21Z

Hi Jens,

Several embedded storage controllers need support for DMA segments that are
smaller than the size of one virtual memory page. Hence this patch series.
Please consider this patch series for the next merge window.

Thanks,

Bart.

Changes compared to v1:
- Added a CONFIG variable that controls whether or not small segment support
is enabled.
- Improved patch descriptions.

Bart Van Assche (8):
block: Introduce CONFIG_BLK_SUB_PAGE_SEGMENTS and
QUEUE_FLAG_SUB_PAGE_SEGMENTS
block: Support configuring limits below the page size
block: Support submitting passthrough requests with small segments
block: Add support for filesystem requests and small segments
block: Add support for small segments in blk_rq_map_user_iov()
scsi: core: Set the SUB_PAGE_SEGMENTS request queue flag
scsi_debug: Support configuring the maximum segment size
null_blk: Support configuring the maximum segment size

block/Kconfig | 9 +++++++
block/blk-map.c | 43 ++++++++++++++++++++++++++-----
block/blk-merge.c | 6 +++--
block/blk-mq.c | 2 ++
block/blk-settings.c | 20 ++++++++------
block/blk.h | 14 +++++++++-
drivers/block/null_blk/main.c | 20 +++++++++++---
drivers/block/null_blk/null_blk.h | 1 +
drivers/scsi/scsi_debug.c | 3 +++
drivers/scsi/scsi_lib.c | 2 ++
include/linux/blkdev.h | 7 +++++
11 files changed, 107 insertions(+), 20 deletions(-)