From ca4b2a011948fae4e4d31490107db4926385a983 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Matias=20Bj=C3=B8rling?= Date: Fri, 6 Jul 2018 19:38:39 +0200 Subject: [PATCH] null_blk: add zone support MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Adds support for exposing a null_blk device through the zone device interface. The interface is managed with the parameters zoned and zone_size. If zoned is set, the null_blk instance registers as a zoned block device. The zone_size parameter defines how big each zone will be. Signed-off-by: Matias Bjørling Signed-off-by: Bart Van Assche Signed-off-by: Damien Le Moal Signed-off-by: Jens Axboe --- Documentation/block/null_blk.txt | 7 ++ drivers/block/Makefile | 5 +- drivers/block/null_blk.c | 48 +++++++++- drivers/block/null_blk.h | 28 ++++++ drivers/block/null_blk_zoned.c | 149 +++++++++++++++++++++++++++++++ 5 files changed, 234 insertions(+), 3 deletions(-) create mode 100644 drivers/block/null_blk_zoned.c diff --git a/Documentation/block/null_blk.txt b/Documentation/block/null_blk.txt index 07f147381f32..ea2dafe49ae8 100644 --- a/Documentation/block/null_blk.txt +++ b/Documentation/block/null_blk.txt @@ -85,3 +85,10 @@ shared_tags=[0/1]: Default: 0 0: Tag set is not shared. 1: Tag set shared between devices for blk-mq. Only makes sense with nr_devices > 1, otherwise there's no tag set to share. + +zoned=[0/1]: Default: 0 + 0: Block device is exposed as a random-access block device. + 1: Block device is exposed as a host-managed zoned block device. + +zone_size=[MB]: Default: 256 + Per zone size when exposed as a zoned block device. Must be a power of two. diff --git a/drivers/block/Makefile b/drivers/block/Makefile index dc061158b403..a0d88aa0c05d 100644 --- a/drivers/block/Makefile +++ b/drivers/block/Makefile @@ -36,8 +36,11 @@ obj-$(CONFIG_BLK_DEV_RBD) += rbd.o obj-$(CONFIG_BLK_DEV_PCIESSD_MTIP32XX) += mtip32xx/ obj-$(CONFIG_BLK_DEV_RSXX) += rsxx/ -obj-$(CONFIG_BLK_DEV_NULL_BLK) += null_blk.o obj-$(CONFIG_ZRAM) += zram/ +obj-$(CONFIG_BLK_DEV_NULL_BLK) += null_blk_mod.o +null_blk_mod-objs := null_blk.o +null_blk_mod-$(CONFIG_BLK_DEV_ZONED) += null_blk_zoned.o + skd-y := skd_main.o swim_mod-y := swim.o swim_asm.o diff --git a/drivers/block/null_blk.c b/drivers/block/null_blk.c index 47dd08499145..86cafa6d3b41 100644 --- a/drivers/block/null_blk.c +++ b/drivers/block/null_blk.c @@ -180,6 +180,14 @@ static bool g_use_per_node_hctx; module_param_named(use_per_node_hctx, g_use_per_node_hctx, bool, 0444); MODULE_PARM_DESC(use_per_node_hctx, "Use per-node allocation for hardware context queues. Default: false"); +static bool g_zoned; +module_param_named(zoned, g_zoned, bool, S_IRUGO); +MODULE_PARM_DESC(zoned, "Make device as a host-managed zoned block device. Default: false"); + +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 struct nullb_device *null_alloc_dev(void); static void null_free_dev(struct nullb_device *dev); static void null_del_dev(struct nullb *nullb); @@ -283,6 +291,8 @@ NULLB_DEVICE_ATTR(memory_backed, bool); NULLB_DEVICE_ATTR(discard, bool); NULLB_DEVICE_ATTR(mbps, uint); NULLB_DEVICE_ATTR(cache_size, ulong); +NULLB_DEVICE_ATTR(zoned, bool); +NULLB_DEVICE_ATTR(zone_size, ulong); static ssize_t nullb_device_power_show(struct config_item *item, char *page) { @@ -395,6 +405,8 @@ static struct configfs_attribute *nullb_device_attrs[] = { &nullb_device_attr_mbps, &nullb_device_attr_cache_size, &nullb_device_attr_badblocks, + &nullb_device_attr_zoned, + &nullb_device_attr_zone_size, NULL, }; @@ -447,7 +459,7 @@ nullb_group_drop_item(struct config_group *group, struct config_item *item) static ssize_t memb_group_features_show(struct config_item *item, char *page) { - return snprintf(page, PAGE_SIZE, "memory_backed,discard,bandwidth,cache,badblocks\n"); + return snprintf(page, PAGE_SIZE, "memory_backed,discard,bandwidth,cache,badblocks,zoned,zone_size\n"); } CONFIGFS_ATTR_RO(memb_group_, features); @@ -506,6 +518,8 @@ static struct nullb_device *null_alloc_dev(void) dev->hw_queue_depth = g_hw_queue_depth; dev->blocking = g_blocking; dev->use_per_node_hctx = g_use_per_node_hctx; + dev->zoned = g_zoned; + dev->zone_size = g_zone_size; return dev; } @@ -514,6 +528,7 @@ static void null_free_dev(struct nullb_device *dev) if (!dev) return; + null_zone_exit(dev); badblocks_exit(&dev->badblocks); kfree(dev); } @@ -1146,6 +1161,11 @@ static blk_status_t null_handle_cmd(struct nullb_cmd *cmd) struct nullb *nullb = dev->nullb; int err = 0; + if (req_op(cmd->rq) == REQ_OP_ZONE_REPORT) { + cmd->error = null_zone_report(nullb, cmd); + goto out; + } + if (test_bit(NULLB_DEV_FL_THROTTLED, &dev->flags)) { struct request *rq = cmd->rq; @@ -1210,6 +1230,13 @@ static blk_status_t null_handle_cmd(struct nullb_cmd *cmd) } } cmd->error = errno_to_blk_status(err); + + if (!cmd->error && dev->zoned) { + if (req_op(cmd->rq) == REQ_OP_WRITE) + null_zone_write(cmd); + else if (req_op(cmd->rq) == REQ_OP_ZONE_RESET) + null_zone_reset(cmd); + } out: /* Complete IO by inline, softirq or timer */ switch (dev->irqmode) { @@ -1737,6 +1764,15 @@ static int null_add_dev(struct nullb_device *dev) blk_queue_flush_queueable(nullb->q, true); } + if (dev->zoned) { + rv = null_zone_init(dev); + if (rv) + goto out_cleanup_blk_queue; + + blk_queue_chunk_sectors(nullb->q, dev->zone_size_sects); + nullb->q->limits.zoned = BLK_ZONED_HM; + } + nullb->q->queuedata = nullb; blk_queue_flag_set(QUEUE_FLAG_NONROT, nullb->q); blk_queue_flag_clear(QUEUE_FLAG_ADD_RANDOM, nullb->q); @@ -1755,13 +1791,16 @@ static int null_add_dev(struct nullb_device *dev) rv = null_gendisk_register(nullb); if (rv) - goto out_cleanup_blk_queue; + goto out_cleanup_zone; mutex_lock(&lock); list_add_tail(&nullb->list, &nullb_list); mutex_unlock(&lock); return 0; +out_cleanup_zone: + if (dev->zoned) + null_zone_exit(dev); out_cleanup_blk_queue: blk_cleanup_queue(nullb->q); out_cleanup_tags: @@ -1788,6 +1827,11 @@ static int __init null_init(void) g_bs = PAGE_SIZE; } + if (!is_power_of_2(g_zone_size)) { + pr_err("null_blk: zone_size must be power-of-two\n"); + return -EINVAL; + } + if (g_queue_mode == NULL_Q_MQ && g_use_per_node_hctx) { if (g_submit_queues != nr_online_nodes) { pr_warn("null_blk: submit_queues param is set to %u.\n", diff --git a/drivers/block/null_blk.h b/drivers/block/null_blk.h index d82c5501806d..d81781f22dba 100644 --- a/drivers/block/null_blk.h +++ b/drivers/block/null_blk.h @@ -41,9 +41,14 @@ struct nullb_device { unsigned int curr_cache; struct badblocks badblocks; + unsigned int nr_zones; + struct blk_zone *zones; + sector_t zone_size_sects; + unsigned long size; /* device size in MB */ 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 submit_queues; /* number of submission queues */ unsigned int home_node; /* home node for the device */ unsigned int queue_mode; /* block interface */ @@ -57,6 +62,7 @@ struct nullb_device { bool power; /* power on/off the device */ bool memory_backed; /* if data is stored in memory */ bool discard; /* if support discard */ + bool zoned; /* if device is zoned */ }; struct nullb { @@ -77,4 +83,26 @@ struct nullb { unsigned int nr_queues; char disk_name[DISK_NAME_LEN]; }; + +#ifdef CONFIG_BLK_DEV_ZONED +int null_zone_init(struct nullb_device *dev); +void null_zone_exit(struct nullb_device *dev); +blk_status_t null_zone_report(struct nullb *nullb, + struct nullb_cmd *cmd); +void null_zone_write(struct nullb_cmd *cmd); +void null_zone_reset(struct nullb_cmd *cmd); +#else +static inline int null_zone_init(struct nullb_device *dev) +{ + return -EINVAL; +} +static inline void null_zone_exit(struct nullb_device *dev) {} +static inline blk_status_t null_zone_report(struct nullb *nullb, + struct nullb_cmd *cmd) +{ + return BLK_STS_NOTSUPP; +} +static inline void null_zone_write(struct nullb_cmd *cmd) {} +static inline void null_zone_reset(struct nullb_cmd *cmd) {} +#endif /* CONFIG_BLK_DEV_ZONED */ #endif /* __NULL_BLK_H */ diff --git a/drivers/block/null_blk_zoned.c b/drivers/block/null_blk_zoned.c new file mode 100644 index 000000000000..a979ca00d7be --- /dev/null +++ b/drivers/block/null_blk_zoned.c @@ -0,0 +1,149 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include "null_blk.h" + +/* zone_size in MBs to sectors. */ +#define ZONE_SIZE_SHIFT 11 + +static inline unsigned int null_zone_no(struct nullb_device *dev, sector_t sect) +{ + return sect >> ilog2(dev->zone_size_sects); +} + +int null_zone_init(struct nullb_device *dev) +{ + sector_t dev_size = (sector_t)dev->size * 1024 * 1024; + sector_t sector = 0; + unsigned int i; + + if (!is_power_of_2(dev->zone_size)) { + pr_err("null_blk: zone_size must be power-of-two\n"); + return -EINVAL; + } + + dev->zone_size_sects = dev->zone_size << ZONE_SIZE_SHIFT; + dev->nr_zones = dev_size >> + (SECTOR_SHIFT + ilog2(dev->zone_size_sects)); + dev->zones = kvmalloc_array(dev->nr_zones, sizeof(struct blk_zone), + GFP_KERNEL | __GFP_ZERO); + if (!dev->zones) + return -ENOMEM; + + for (i = 0; i < dev->nr_zones; i++) { + struct blk_zone *zone = &dev->zones[i]; + + zone->start = zone->wp = sector; + zone->len = dev->zone_size_sects; + zone->type = BLK_ZONE_TYPE_SEQWRITE_REQ; + zone->cond = BLK_ZONE_COND_EMPTY; + + sector += dev->zone_size_sects; + } + + return 0; +} + +void null_zone_exit(struct nullb_device *dev) +{ + kvfree(dev->zones); +} + +static void null_zone_fill_rq(struct nullb_device *dev, struct request *rq, + unsigned int zno, unsigned int nr_zones) +{ + struct blk_zone_report_hdr *hdr = NULL; + struct bio_vec bvec; + struct bvec_iter iter; + void *addr; + unsigned int zones_to_cpy; + + bio_for_each_segment(bvec, rq->bio, iter) { + addr = kmap_atomic(bvec.bv_page); + + zones_to_cpy = bvec.bv_len / sizeof(struct blk_zone); + + if (!hdr) { + hdr = (struct blk_zone_report_hdr *)addr; + hdr->nr_zones = nr_zones; + zones_to_cpy--; + addr += sizeof(struct blk_zone_report_hdr); + } + + zones_to_cpy = min_t(unsigned int, zones_to_cpy, nr_zones); + + memcpy(addr, &dev->zones[zno], + zones_to_cpy * sizeof(struct blk_zone)); + + kunmap_atomic(addr); + + nr_zones -= zones_to_cpy; + zno += zones_to_cpy; + + if (!nr_zones) + break; + } +} + +blk_status_t null_zone_report(struct nullb *nullb, + struct nullb_cmd *cmd) +{ + struct nullb_device *dev = nullb->dev; + struct request *rq = cmd->rq; + unsigned int zno = null_zone_no(dev, blk_rq_pos(rq)); + unsigned int nr_zones = dev->nr_zones - zno; + unsigned int max_zones = (blk_rq_bytes(rq) / + sizeof(struct blk_zone)) - 1; + + nr_zones = min_t(unsigned int, nr_zones, max_zones); + + null_zone_fill_rq(nullb->dev, rq, zno, nr_zones); + + return BLK_STS_OK; +} + +void null_zone_write(struct nullb_cmd *cmd) +{ + struct nullb_device *dev = cmd->nq->dev; + struct request *rq = cmd->rq; + sector_t sector = blk_rq_pos(rq); + unsigned int rq_sectors = blk_rq_sectors(rq); + unsigned int zno = null_zone_no(dev, sector); + struct blk_zone *zone = &dev->zones[zno]; + + switch (zone->cond) { + case BLK_ZONE_COND_FULL: + /* Cannot write to a full zone */ + cmd->error = BLK_STS_IOERR; + break; + case BLK_ZONE_COND_EMPTY: + case BLK_ZONE_COND_IMP_OPEN: + /* Writes must be at the write pointer position */ + if (blk_rq_pos(rq) != zone->wp) { + cmd->error = BLK_STS_IOERR; + break; + } + + if (zone->cond == BLK_ZONE_COND_EMPTY) + zone->cond = BLK_ZONE_COND_IMP_OPEN; + + zone->wp += rq_sectors; + if (zone->wp == zone->start + zone->len) + zone->cond = BLK_ZONE_COND_FULL; + break; + default: + /* Invalid zone condition */ + cmd->error = BLK_STS_IOERR; + break; + } +} + +void null_zone_reset(struct nullb_cmd *cmd) +{ + struct nullb_device *dev = cmd->nq->dev; + struct request *rq = cmd->rq; + unsigned int zno = null_zone_no(dev, blk_rq_pos(rq)); + struct blk_zone *zone = &dev->zones[zno]; + + zone->cond = BLK_ZONE_COND_EMPTY; + zone->wp = zone->start; +} -- 2.30.2