[PATCH v2 00/11] Zoned block device support improvements

Damien Le Moal
2018-10-11T07:09:41Z

This series improves zoned block device support (reduce overhead) and
introduces many simplifications to the code (overall, there are more deletions
than insertions).

In more details:
* Patches 1 to 3 are SCSI side (sd driver) cleanups and improvements reducing
the overhead of report zones command execution during disk scan and
revalidation.
* Patches 4 to 9 improve the useability and user API of zoned block devices.
* Patch 10 is the main part of this series. This patch replaces the
REQ_OP_ZONE_REPORT BIO/request operation for executing report zones commands
with a block device file operation, removing the need for the command reply
payload in-place rewriting in the BIO buffer. This leads to major
simplification of the code in many places.
* Patch 11 further simplifies the code of low level drivers by providing a
generic implementation of zoned block device request queue zone bitmaps
initialization and revalidation.

Please consider the addition of these patches in 4.20.
Comments are as always welcome.

Changes from v1:
* Addressed Christoph's and Bart's comments
* Fixed several compilation errors with zoned block device support disabled
* Rebased on latest rc including the most recent dm patches

Christoph Hellwig (1):
block: add a report_zones method

Damien Le Moal (10):
scsi: sd_zbc: Rearrange code
scsi: sd_zbc: Reduce boot device scan and revalidate time
scsi: sd_zbc: Fix sd_zbc_check_zones() error checks
block: Introduce blkdev_nr_zones() helper
block: Limit allocation of zone descriptors for report zones
block: Introduce BLKGETZONESZ ioctl
block: Introduce BLKGETNRZONES ioctl
block: Improve zone reset execution
block: Expose queue nr_zones in sysfs
block: Introduce blk_revalidate_disk_zones()

block/blk-core.c | 1 -
block/blk-lib.c | 13 +-
block/blk-mq-debugfs.c | 1 -
block/blk-sysfs.c | 13 +
block/blk-zoned.c | 359 +++++++++++++++---------
block/blk.h | 8 +
block/ioctl.c | 4 +
drivers/block/null_blk.h | 11 +-
drivers/block/null_blk_main.c | 30 +-
drivers/block/null_blk_zoned.c | 57 +---
drivers/md/dm-flakey.c | 30 +-
drivers/md/dm-linear.c | 35 ++-
drivers/md/dm-table.c | 10 +
drivers/md/dm-zoned-target.c | 3 +-
drivers/md/dm.c | 169 ++++++-----
drivers/scsi/sd.c | 15 +-
drivers/scsi/sd.h | 15 +-
drivers/scsi/sd_zbc.c | 497 +++++++++------------------------
include/linux/blk_types.h | 2 -
include/linux/blkdev.h | 22 +-
include/linux/device-mapper.h | 12 +-
include/trace/events/f2fs.h | 1 -
include/uapi/linux/blkzoned.h | 3 +
23 files changed, 591 insertions(+), 720 deletions(-)

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2.17.1