On 10/22/2018 01:25 PM, Masato Suzuki wrote:
> Allow the creation of conventional zones by adding the nr_conv_zones
> configuration attribute. This new attribute is used only for zoned devices and
> indicates the number of conventional zones to create. The default value is 0.
> Since host-managed zoned block devices must always have at least one sequential
> zone, if the value of nr_conv_zones is larger than or equal to the total number
> of zones of the device nr_zones, nr_conv_zones is automatically changed to
> nr_zones - 1.
>
> Signed-off-by: Masato Suzuki <masato.suzuki@xxxxxxx>
> ---
> drivers/block/null_blk.h | 1 +
> drivers/block/null_blk_main.c | 7 +++++++
> drivers/block/null_blk_zoned.c | 27 ++++++++++++++++++++++++++-
> 3 files changed, 34 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/block/null_blk.h b/drivers/block/null_blk.h
> index 34e0030f0592..b9d0b57d3642 100644
> --- a/drivers/block/null_blk.h
> +++ b/drivers/block/null_blk.h
> @@ -49,6 +49,7 @@ struct nullb_device {
> unsigned long completion_nsec; /* time in ns to complete a request */
> unsigned long cache_size; /* disk cache size in MB */
> unsigned long zone_size; /* zone size in MB if device is zoned */
> + unsigned int nr_conv_zones; /* number of conventional zones */
> unsigned int submit_queues; /* number of submission queues */
> unsigned int home_node; /* home node for the device */
> unsigned int queue_mode; /* block interface */
> diff --git a/drivers/block/null_blk_main.c b/drivers/block/null_blk_main.c
> index 093b614d6524..ce6fa0ddc9f9 100644
> --- a/drivers/block/null_blk_main.c
> +++ b/drivers/block/null_blk_main.c
> @@ -188,6 +188,10 @@ static unsigned long g_zone_size = 256;
> module_param_named(zone_size, g_zone_size, ulong, S_IRUGO);
> MODULE_PARM_DESC(zone_size, "Zone size in MB when block device is zoned. Must be power-of-two: Default: 256");
>
> +static unsigned int g_nr_conv_zones;
> +module_param_named(nr_conv_zones, g_nr_conv_zones, uint, S_IRUGO);
> +MODULE_PARM_DESC(nr_conv_zones, "Number of conventional zones when block device is zoned. Default: 0");
> +
> 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);
> @@ -293,6 +297,7 @@ NULLB_DEVICE_ATTR(mbps, uint);
> NULLB_DEVICE_ATTR(cache_size, ulong);
> NULLB_DEVICE_ATTR(zoned, bool);
> NULLB_DEVICE_ATTR(zone_size, ulong);
> +NULLB_DEVICE_ATTR(nr_conv_zones, uint);
>
> static ssize_t nullb_device_power_show(struct config_item *item, char *page)
> {
> @@ -407,6 +412,7 @@ static struct configfs_attribute *nullb_device_attrs[] = {
> &nullb_device_attr_badblocks,
> &nullb_device_attr_zoned,
> &nullb_device_attr_zone_size,
> + &nullb_device_attr_nr_conv_zones,
> NULL,
> };
>
> @@ -520,6 +526,7 @@ static struct nullb_device *null_alloc_dev(void)
> dev->use_per_node_hctx = g_use_per_node_hctx;
> dev->zoned = g_zoned;
> dev->zone_size = g_zone_size;
> + dev->nr_conv_zones = g_nr_conv_zones;
> return dev;
> }
>
> diff --git a/drivers/block/null_blk_zoned.c b/drivers/block/null_blk_zoned.c
> index 7c6b86d98700..cf0d07491d29 100644
> --- a/drivers/block/null_blk_zoned.c
> +++ b/drivers/block/null_blk_zoned.c
> @@ -29,7 +29,25 @@ int null_zone_init(struct nullb_device *dev)
> if (!dev->zones)
> return -ENOMEM;
>
> - for (i = 0; i < dev->nr_zones; i++) {
> + if (dev->nr_conv_zones >= dev->nr_zones) {
> + dev->nr_conv_zones = dev->nr_zones - 1;
> + pr_info("null_blk: changed the number of conventional zones to %u",
> + dev->nr_conv_zones);
> + }
> +
> + for (i = 0; i < dev->nr_conv_zones; i++ ) {
> + struct blk_zone *zone = &dev->zones[i];
> +
> + zone->start = sector;
> + zone->len = dev->zone_size_sects;
> + zone->wp = zone->start + zone->len;
> + zone->type = BLK_ZONE_TYPE_CONVENTIONAL;
> + zone->cond = BLK_ZONE_COND_NOT_WP;
> +
> + sector += dev->zone_size_sects;
> + }
> +
> + for (i = dev->nr_conv_zones; i < dev->nr_zones; i++) {
> struct blk_zone *zone = &dev->zones[i];
>
> zone->start = zone->wp = sector;
> @@ -125,6 +143,8 @@ void null_zone_write(struct nullb_cmd *cmd, sector_t sector,
> if (zone->wp == zone->start + zone->len)
> zone->cond = BLK_ZONE_COND_FULL;
> break;
> + case BLK_ZONE_COND_NOT_WP:
> + break;
> default:
> /* Invalid zone condition */
> cmd->error = BLK_STS_IOERR;
> @@ -138,6 +158,11 @@ void null_zone_reset(struct nullb_cmd *cmd, sector_t sector)
> unsigned int zno = null_zone_no(dev, sector);
> struct blk_zone *zone = &dev->zones[zno];
>
> + if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL) {
> + cmd->error = BLK_STS_IOERR;
> + return;
> + }
> +
> zone->cond = BLK_ZONE_COND_EMPTY;
> zone->wp = zone->start;
> }
>
Looks good to me. One nitpick, might be better to rename the sysfs
attribute nr_conv_zones to zone_nr_conv or similar to keep the zone
attributes grouped together.
I'll let Jens be the judge.
Reviewed-by: Matias Bjørling <matias.bjorling@xxxxxxx>
