On 10/6/22 14:05, Chaitanya Kulkarni wrote:
> For a Zoned Block Device zone reset all is emulated if underlaying
> device doesn't support REQ_OP_ZONE_RESET_ALL operation. In null_blk
> Zoned mode there is no way to test zone reset all emulation present in
> the block layer since we enable it by default :-
>
> blkdev_zone_mgmt()
> blkdev_zone_reset_all_emulation() <---
> blkdev_zone_reset_all()
>
> Add a module parameter zone_reset_all to enable or disable
> REQ_OP_ZONE_RESET_ALL, enable it by default to retain the existing
> behaviour.
>
> Signed-off-by: Chaitanya Kulkarni <kch@xxxxxxxxxx>
> ---
> # git log -1
> commit 8ca0bd53a9c9e2f58c4fc9e38e3f5f82d26d3851 (HEAD -> for-next)
> Author: Chaitanya Kulkarni <kch@xxxxxxxxxx>
> Date: Wed Oct 5 21:57:00 2022 -0700
>
> null_blk: allow REQ_OP_ZONE_RESET_ALL to configure
>
> For a Zoned Block Device zone reset all is emulated if underlaying
> device doesn't support REQ_OP_ZONE_RESET_ALL operation. In null_blk
> Zoned mode there is no way to test zone reset all emulation present in
> the block layer since we enable it by default :-
>
> blkdev_zone_mgmt()
> blkdev_zone_reset_all_emulation() <---
> blkdev_zone_reset_all()
>
> Add a module parameter zone_reset_all to enable or disable
> REQ_OP_ZONE_RESET_ALL, enable it by default to retain the existing
> behaviour.
>
> Signed-off-by: Chaitanya Kulkarni <kch@xxxxxxxxxx>
> # ./compile_nullb.sh
> + umount /mnt/nullb0
> umount: /mnt/nullb0: not mounted.
> + rmdir 'config/nullb/nullb*'
> rmdir: failed to remove 'config/nullb/nullb*': No such file or directory
> + dmesg -c
> + modprobe -r null_blk
> + lsmod
> + grep null_blk
> ++ nproc
> + make -j 48 M=drivers/block modules
> + HOST=drivers/block/null_blk/
> ++ uname -r
> + HOST_DEST=/lib/modules/6.0.0-rc7blk+/kernel/drivers/block/null_blk/
> + cp drivers/block/null_blk//null_blk.ko /lib/modules/6.0.0-rc7blk+/kernel/drivers/block/null_blk//
> + ls -lrth /lib/modules/6.0.0-rc7blk+/kernel/drivers/block/null_blk//null_blk.ko
> -rw-r--r--. 1 root root 1.2M Oct 5 21:57 /lib/modules/6.0.0-rc7blk+/kernel/drivers/block/null_blk//null_blk.ko
> + sleep 1
> + dmesg -c
> # modprobe null_blk gb=1 zoned=1 zone_size=128 <---
> # lsblk
> NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
> sda 8:0 0 50G 0 disk
> ├─sda1 8:1 0 1G 0 part /boot
> └─sda2 8:2 0 49G 0 part /home
> sdb 8:16 0 100G 0 disk /mnt/data
> sr0 11:0 1 1024M 0 rom
> nullb0 250:0 0 1G 0 disk
> zram0 251:0 0 8G 0 disk [SWAP]
> vda 252:0 0 512M 0 disk
> nvme0n1 259:0 0 1G 0 disk
> # blkzone reset /dev/nullb0
> # dmesg -c
> [ 397.079221] null_blk: disk nullb0 created
> [ 397.079226] null_blk: module loaded
> [ 406.626500] blkdev_zone_reset_all 237 <---
> # modprobe -r null_blk
> #
> #
> #
> # modprobe null_blk gb=1 zoned=1 zone_size=128 zone_reset_all=0 <---
> # lsblk
> NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
> sda 8:0 0 50G 0 disk
> ├─sda1 8:1 0 1G 0 part /boot
> └─sda2 8:2 0 49G 0 part /home
> sdb 8:16 0 100G 0 disk /mnt/data
> sr0 11:0 1 1024M 0 rom
> nullb0 250:0 0 1G 0 disk
> zram0 251:0 0 8G 0 disk [SWAP]
> vda 252:0 0 512M 0 disk
> nvme0n1 259:0 0 1G 0 disk
> # blkzone reset /dev/nullb0
> # dmesg -c
> [ 425.456187] null_blk: disk nullb0 created
> [ 425.456192] null_blk: module loaded
> [ 438.419529] blkdev_zone_reset_all_emulated 197 <---
> # modprobe -r null_blk
> #
> ---
> drivers/block/null_blk/main.c | 5 +++++
> drivers/block/null_blk/null_blk.h | 1 +
> drivers/block/null_blk/zoned.c | 3 ++-
> 3 files changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/block/null_blk/main.c b/drivers/block/null_blk/main.c
> index 8b7f42024f14..a0572e6c28ce 100644
> --- a/drivers/block/null_blk/main.c
> +++ b/drivers/block/null_blk/main.c
> @@ -260,6 +260,10 @@ static unsigned int g_zone_max_active;
> module_param_named(zone_max_active, g_zone_max_active, uint, 0444);
> MODULE_PARM_DESC(zone_max_active, "Maximum number of active zones when block device is zoned. Default: 0 (no limit)");
>
> +static bool g_zone_reset_all = true;
> +module_param_named(zone_reset_all, g_zone_reset_all, bool, 0444);
Nit: Why read-only ? You can make it writable without any issue, no ?
> +MODULE_PARM_DESC(zone_reset_all, "Allow REQ_OP_ZONE_RESET_ALL. Default: true");
> +
> static struct nullb_device *null_alloc_dev(void);
> static void null_free_dev(struct nullb_device *dev);
> static void null_del_dev(struct nullb *nullb);
> @@ -715,6 +719,7 @@ static struct nullb_device *null_alloc_dev(void)
> dev->zone_nr_conv = g_zone_nr_conv;
> dev->zone_max_open = g_zone_max_open;
> dev->zone_max_active = g_zone_max_active;
> + dev->zone_reset_all = g_zone_reset_all;
> dev->virt_boundary = g_virt_boundary;
> dev->no_sched = g_no_sched;
> dev->shared_tag_bitmap = g_shared_tag_bitmap;
> diff --git a/drivers/block/null_blk/null_blk.h b/drivers/block/null_blk/null_blk.h
> index e692c2a7369e..e7efe8de4ebf 100644
> --- a/drivers/block/null_blk/null_blk.h
> +++ b/drivers/block/null_blk/null_blk.h
> @@ -115,6 +115,7 @@ struct nullb_device {
> bool discard; /* if support discard */
> bool write_zeroes; /* if support write_zeroes */
> bool zoned; /* if device is zoned */
> + bool zone_reset_all; /* if support REQ_OP_ZONE_RESET_ALL */
> bool virt_boundary; /* virtual boundary on/off for the device */
> bool no_sched; /* no IO scheduler for the device */
> bool shared_tag_bitmap; /* use hostwide shared tags */
> diff --git a/drivers/block/null_blk/zoned.c b/drivers/block/null_blk/zoned.c
> index 55a69e48ef8b..7310d1c3f9ec 100644
> --- a/drivers/block/null_blk/zoned.c
> +++ b/drivers/block/null_blk/zoned.c
> @@ -160,7 +160,8 @@ int null_register_zoned_dev(struct nullb *nullb)
> struct request_queue *q = nullb->q;
>
> disk_set_zoned(nullb->disk, BLK_ZONED_HM);
> - blk_queue_flag_set(QUEUE_FLAG_ZONE_RESETALL, q);
> + if (dev->zone_reset_all)
> + blk_queue_flag_set(QUEUE_FLAG_ZONE_RESETALL, q);
> blk_queue_required_elevator_features(q, ELEVATOR_F_ZBD_SEQ_WRITE);
>
> if (queue_is_mq(q)) {
--
Damien Le Moal
Western Digital Research
