Jens, This series provides fixes and improvements for null_blk. The first two patches are bug fixes which likely should go into 5.10. The first patch fixes a problem with zone initialization when the device capacity is not a multiple of the zone size and the second patch fixes zone append handling. The following patches are improvements and cleanups: * Patch 3 makes sure that the device max_sectors limit is aligned to the block size. * Patch 4 improves zone locking overall, and especially the memory backing disabled case by introducing a spinlock array to implement a per zone lock in place of a global lock. With this patch, write performance remains mostly unchanged, but read performance with a multi-queue setup more than double from 1.3 MIOPS to 3.3 MIOPS (4K random reads to zones with fio zonemode=zbd). * Patch 5 improves implicit zone close * Patch 6 and 7 cleanup discard handling code and use that code to free the memory backing a zone that is being reset. * Patch 8 adds the max_sectors configuration option to allow changing the max_sectors/max_hw_sectors of the device. * Finally, patch 9 moves nullblk into its own directory under drivers/block/null_blk/ Comments are as always welcome. Changes from v3: * Use inline function for zone res lock instead of macro as suggested by Christoph. * Added Reviewed-by tags Changes from v2: * Make patch 3 a generic blk-settings fix * Reworked patch 4 zone locking as suggested by Christoph * Small change in patch 6 as suggested by Christoph Changes from v1: * Added patch 2, 3 and 8. * Fix the last patch as suggested by Bart (file names under driver/block/null_blk/) * Reworded patch 1 commit message to more correctly describe the problem. Damien Le Moal (9): null_blk: Fix zone size initialization null_blk: Fail zone append to conventional zones block: Align max_hw_sectors to logical blocksize null_blk: improve zone locking null_blk: Improve implicit zone close null_blk: cleanup discard handling null_blk: discard zones on reset null_blk: Allow controlling max_hw_sectors limit null_blk: Move driver into its own directory block/blk-settings.c | 23 +- drivers/block/Kconfig | 8 +- drivers/block/Makefile | 7 +- drivers/block/null_blk/Kconfig | 12 + drivers/block/null_blk/Makefile | 11 + .../{null_blk_main.c => null_blk/main.c} | 63 ++-- drivers/block/{ => null_blk}/null_blk.h | 32 +- .../{null_blk_trace.c => null_blk/trace.c} | 2 +- .../{null_blk_trace.h => null_blk/trace.h} | 2 +- .../{null_blk_zoned.c => null_blk/zoned.c} | 333 +++++++++++------- 10 files changed, 317 insertions(+), 176 deletions(-) create mode 100644 drivers/block/null_blk/Kconfig create mode 100644 drivers/block/null_blk/Makefile rename drivers/block/{null_blk_main.c => null_blk/main.c} (97%) rename drivers/block/{ => null_blk}/null_blk.h (83%) rename drivers/block/{null_blk_trace.c => null_blk/trace.c} (93%) rename drivers/block/{null_blk_trace.h => null_blk/trace.h} (97%) rename drivers/block/{null_blk_zoned.c => null_blk/zoned.c} (68%) -- 2.28.0