From 6a0cb1bc106fc07ce0443303bcdb7f7da5131e5c Mon Sep 17 00:00:00 2001 From: Hannes Reinecke Date: Tue, 18 Oct 2016 15:40:33 +0900 Subject: [PATCH] block: Implement support for zoned block devices Implement zoned block device zone information reporting and reset. Zone information are reported as struct blk_zone. This implementation does not differentiate between host-aware and host-managed device models and is valid for both. Two functions are provided: blkdev_report_zones for discovering the zone configuration of a zoned block device, and blkdev_reset_zones for resetting the write pointer of sequential zones. The helper function blk_queue_zone_size and bdev_zone_size are also provided for, as the name suggest, obtaining the zone size (in 512B sectors) of the zones of the device. Signed-off-by: Hannes Reinecke [Damien: * Removed the zone cache * Implement report zones operation based on earlier proposal by Shaun Tancheff ] Signed-off-by: Damien Le Moal Reviewed-by: Christoph Hellwig Reviewed-by: Martin K. Petersen Reviewed-by: Shaun Tancheff Tested-by: Shaun Tancheff Signed-off-by: Jens Axboe --- block/Kconfig | 8 ++ block/Makefile | 1 + block/blk-zoned.c | 257 ++++++++++++++++++++++++++++++++++++++++++ include/linux/blkdev.h | 31 +++++ include/uapi/linux/Kbuild | 1 + include/uapi/linux/blkzoned.h | 103 +++++++++++++++++ 6 files changed, 401 insertions(+) create mode 100644 block/blk-zoned.c create mode 100644 include/uapi/linux/blkzoned.h diff --git a/block/Kconfig b/block/Kconfig index 1d4d624..6b0ad08 100644 --- a/block/Kconfig +++ b/block/Kconfig @@ -89,6 +89,14 @@ config BLK_DEV_INTEGRITY T10/SCSI Data Integrity Field or the T13/ATA External Path Protection. If in doubt, say N. +config BLK_DEV_ZONED + bool "Zoned block device support" + ---help--- + Block layer zoned block device support. This option enables + support for ZAC/ZBC host-managed and host-aware zoned block devices. + + Say yes here if you have a ZAC or ZBC storage device. + config BLK_DEV_THROTTLING bool "Block layer bio throttling support" depends on BLK_CGROUP=y diff --git a/block/Makefile b/block/Makefile index 36acdd7..934dac7 100644 --- a/block/Makefile +++ b/block/Makefile @@ -23,3 +23,4 @@ obj-$(CONFIG_BLOCK_COMPAT) += compat_ioctl.o obj-$(CONFIG_BLK_CMDLINE_PARSER) += cmdline-parser.o obj-$(CONFIG_BLK_DEV_INTEGRITY) += bio-integrity.o blk-integrity.o t10-pi.o obj-$(CONFIG_BLK_MQ_PCI) += blk-mq-pci.o +obj-$(CONFIG_BLK_DEV_ZONED) += blk-zoned.o diff --git a/block/blk-zoned.c b/block/blk-zoned.c new file mode 100644 index 0000000..1603573 --- /dev/null +++ b/block/blk-zoned.c @@ -0,0 +1,257 @@ +/* + * Zoned block device handling + * + * Copyright (c) 2015, Hannes Reinecke + * Copyright (c) 2015, SUSE Linux GmbH + * + * Copyright (c) 2016, Damien Le Moal + * Copyright (c) 2016, Western Digital + */ + +#include +#include +#include +#include + +static inline sector_t blk_zone_start(struct request_queue *q, + sector_t sector) +{ + sector_t zone_mask = blk_queue_zone_size(q) - 1; + + return sector & ~zone_mask; +} + +/* + * Check that a zone report belongs to the partition. + * If yes, fix its start sector and write pointer, copy it in the + * zone information array and return true. Return false otherwise. + */ +static bool blkdev_report_zone(struct block_device *bdev, + struct blk_zone *rep, + struct blk_zone *zone) +{ + sector_t offset = get_start_sect(bdev); + + if (rep->start < offset) + return false; + + rep->start -= offset; + if (rep->start + rep->len > bdev->bd_part->nr_sects) + return false; + + if (rep->type == BLK_ZONE_TYPE_CONVENTIONAL) + rep->wp = rep->start + rep->len; + else + rep->wp -= offset; + memcpy(zone, rep, sizeof(struct blk_zone)); + + return true; +} + +/** + * blkdev_report_zones - Get zones information + * @bdev: Target block device + * @sector: Sector from which to report zones + * @zones: Array of zone structures where to return the zones information + * @nr_zones: Number of zone structures in the zone array + * @gfp_mask: Memory allocation flags (for bio_alloc) + * + * Description: + * Get zone information starting from the zone containing @sector. + * The number of zone information reported may be less than the number + * requested by @nr_zones. The number of zones actually reported is + * returned in @nr_zones. + */ +int blkdev_report_zones(struct block_device *bdev, + sector_t sector, + struct blk_zone *zones, + unsigned int *nr_zones, + gfp_t gfp_mask) +{ + struct request_queue *q = bdev_get_queue(bdev); + struct blk_zone_report_hdr *hdr; + unsigned int nrz = *nr_zones; + struct page *page; + unsigned int nr_rep; + size_t rep_bytes; + unsigned int nr_pages; + struct bio *bio; + struct bio_vec *bv; + unsigned int i, n, nz; + unsigned int ofst; + void *addr; + int ret = 0; + + if (!q) + return -ENXIO; + + if (!blk_queue_is_zoned(q)) + return -EOPNOTSUPP; + + if (!nrz) + return 0; + + if (sector > bdev->bd_part->nr_sects) { + *nr_zones = 0; + return 0; + } + + /* + * The zone report has a header. So make room for it in the + * payload. Also make sure that the report fits in a single BIO + * that will not be split down the stack. + */ + rep_bytes = sizeof(struct blk_zone_report_hdr) + + sizeof(struct blk_zone) * nrz; + rep_bytes = (rep_bytes + PAGE_SIZE - 1) & PAGE_MASK; + if (rep_bytes > (queue_max_sectors(q) << 9)) + rep_bytes = queue_max_sectors(q) << 9; + + nr_pages = min_t(unsigned int, BIO_MAX_PAGES, + rep_bytes >> PAGE_SHIFT); + nr_pages = min_t(unsigned int, nr_pages, + queue_max_segments(q)); + + bio = bio_alloc(gfp_mask, nr_pages); + if (!bio) + return -ENOMEM; + + bio->bi_bdev = bdev; + bio->bi_iter.bi_sector = blk_zone_start(q, sector); + bio_set_op_attrs(bio, REQ_OP_ZONE_REPORT, 0); + + for (i = 0; i < nr_pages; i++) { + page = alloc_page(gfp_mask); + if (!page) { + ret = -ENOMEM; + goto out; + } + if (!bio_add_page(bio, page, PAGE_SIZE, 0)) { + __free_page(page); + break; + } + } + + if (i == 0) + ret = -ENOMEM; + else + ret = submit_bio_wait(bio); + if (ret) + goto out; + + /* + * Process the report result: skip the header and go through the + * reported zones to fixup and fixup the zone information for + * partitions. At the same time, return the zone information into + * the zone array. + */ + n = 0; + nz = 0; + nr_rep = 0; + bio_for_each_segment_all(bv, bio, i) { + + if (!bv->bv_page) + break; + + addr = kmap_atomic(bv->bv_page); + + /* Get header in the first page */ + ofst = 0; + if (!nr_rep) { + hdr = (struct blk_zone_report_hdr *) addr; + nr_rep = hdr->nr_zones; + ofst = sizeof(struct blk_zone_report_hdr); + } + + /* Fixup and report zones */ + while (ofst < bv->bv_len && + n < nr_rep && nz < nrz) { + if (blkdev_report_zone(bdev, addr + ofst, &zones[nz])) + nz++; + ofst += sizeof(struct blk_zone); + n++; + } + + kunmap_atomic(addr); + + if (n >= nr_rep || nz >= nrz) + break; + + } + +out: + bio_for_each_segment_all(bv, bio, i) + __free_page(bv->bv_page); + bio_put(bio); + + if (ret == 0) + *nr_zones = nz; + + return ret; +} +EXPORT_SYMBOL_GPL(blkdev_report_zones); + +/** + * blkdev_reset_zones - Reset zones write pointer + * @bdev: Target block device + * @sector: Start sector of the first zone to reset + * @nr_sectors: Number of sectors, at least the length of one zone + * @gfp_mask: Memory allocation flags (for bio_alloc) + * + * Description: + * Reset the write pointer of the zones contained in the range + * @sector..@sector+@nr_sectors. Specifying the entire disk sector range + * is valid, but the specified range should not contain conventional zones. + */ +int blkdev_reset_zones(struct block_device *bdev, + sector_t sector, sector_t nr_sectors, + gfp_t gfp_mask) +{ + struct request_queue *q = bdev_get_queue(bdev); + sector_t zone_sectors; + sector_t end_sector = sector + nr_sectors; + struct bio *bio; + int ret; + + if (!q) + return -ENXIO; + + if (!blk_queue_is_zoned(q)) + return -EOPNOTSUPP; + + if (end_sector > bdev->bd_part->nr_sects) + /* Out of range */ + return -EINVAL; + + /* Check alignment (handle eventual smaller last zone) */ + zone_sectors = blk_queue_zone_size(q); + if (sector & (zone_sectors - 1)) + return -EINVAL; + + if ((nr_sectors & (zone_sectors - 1)) && + end_sector != bdev->bd_part->nr_sects) + return -EINVAL; + + while (sector < end_sector) { + + bio = bio_alloc(gfp_mask, 0); + bio->bi_iter.bi_sector = sector; + bio->bi_bdev = bdev; + bio_set_op_attrs(bio, REQ_OP_ZONE_RESET, 0); + + ret = submit_bio_wait(bio); + bio_put(bio); + + if (ret) + return ret; + + sector += zone_sectors; + + /* This may take a while, so be nice to others */ + cond_resched(); + + } + + return 0; +} +EXPORT_SYMBOL_GPL(blkdev_reset_zones); diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index f19e16b..252043f 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -24,6 +24,7 @@ #include #include #include +#include struct module; struct scsi_ioctl_command; @@ -302,6 +303,21 @@ struct queue_limits { enum blk_zoned_model zoned; }; +#ifdef CONFIG_BLK_DEV_ZONED + +struct blk_zone_report_hdr { + unsigned int nr_zones; + u8 padding[60]; +}; + +extern int blkdev_report_zones(struct block_device *bdev, + sector_t sector, struct blk_zone *zones, + unsigned int *nr_zones, gfp_t gfp_mask); +extern int blkdev_reset_zones(struct block_device *bdev, sector_t sectors, + sector_t nr_sectors, gfp_t gfp_mask); + +#endif /* CONFIG_BLK_DEV_ZONED */ + struct request_queue { /* * Together with queue_head for cacheline sharing @@ -654,6 +670,11 @@ static inline bool blk_queue_is_zoned(struct request_queue *q) } } +static inline unsigned int blk_queue_zone_size(struct request_queue *q) +{ + return blk_queue_is_zoned(q) ? q->limits.chunk_sectors : 0; +} + /* * We regard a request as sync, if either a read or a sync write */ @@ -1401,6 +1422,16 @@ static inline bool bdev_is_zoned(struct block_device *bdev) return false; } +static inline unsigned int bdev_zone_size(struct block_device *bdev) +{ + struct request_queue *q = bdev_get_queue(bdev); + + if (q) + return blk_queue_zone_size(q); + + return 0; +} + static inline int queue_dma_alignment(struct request_queue *q) { return q ? q->dma_alignment : 511; diff --git a/include/uapi/linux/Kbuild b/include/uapi/linux/Kbuild index 6965d09..b2166f2 100644 --- a/include/uapi/linux/Kbuild +++ b/include/uapi/linux/Kbuild @@ -70,6 +70,7 @@ header-y += bfs_fs.h header-y += binfmts.h header-y += blkpg.h header-y += blktrace_api.h +header-y += blkzoned.h header-y += bpf_common.h header-y += bpf_perf_event.h header-y += bpf.h diff --git a/include/uapi/linux/blkzoned.h b/include/uapi/linux/blkzoned.h new file mode 100644 index 0000000..a381721 --- /dev/null +++ b/include/uapi/linux/blkzoned.h @@ -0,0 +1,103 @@ +/* + * Zoned block devices handling. + * + * Copyright (C) 2015 Seagate Technology PLC + * + * Written by: Shaun Tancheff + * + * Modified by: Damien Le Moal + * Copyright (C) 2016 Western Digital + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ +#ifndef _UAPI_BLKZONED_H +#define _UAPI_BLKZONED_H + +#include + +/** + * enum blk_zone_type - Types of zones allowed in a zoned device. + * + * @BLK_ZONE_TYPE_CONVENTIONAL: The zone has no write pointer and can be writen + * randomly. Zone reset has no effect on the zone. + * @BLK_ZONE_TYPE_SEQWRITE_REQ: The zone must be written sequentially + * @BLK_ZONE_TYPE_SEQWRITE_PREF: The zone can be written non-sequentially + * + * Any other value not defined is reserved and must be considered as invalid. + */ +enum blk_zone_type { + BLK_ZONE_TYPE_CONVENTIONAL = 0x1, + BLK_ZONE_TYPE_SEQWRITE_REQ = 0x2, + BLK_ZONE_TYPE_SEQWRITE_PREF = 0x3, +}; + +/** + * enum blk_zone_cond - Condition [state] of a zone in a zoned device. + * + * @BLK_ZONE_COND_NOT_WP: The zone has no write pointer, it is conventional. + * @BLK_ZONE_COND_EMPTY: The zone is empty. + * @BLK_ZONE_COND_IMP_OPEN: The zone is open, but not explicitly opened. + * @BLK_ZONE_COND_EXP_OPEN: The zones was explicitly opened by an + * OPEN ZONE command. + * @BLK_ZONE_COND_CLOSED: The zone was [explicitly] closed after writing. + * @BLK_ZONE_COND_FULL: The zone is marked as full, possibly by a zone + * FINISH ZONE command. + * @BLK_ZONE_COND_READONLY: The zone is read-only. + * @BLK_ZONE_COND_OFFLINE: The zone is offline (sectors cannot be read/written). + * + * The Zone Condition state machine in the ZBC/ZAC standards maps the above + * deinitions as: + * - ZC1: Empty | BLK_ZONE_EMPTY + * - ZC2: Implicit Open | BLK_ZONE_COND_IMP_OPEN + * - ZC3: Explicit Open | BLK_ZONE_COND_EXP_OPEN + * - ZC4: Closed | BLK_ZONE_CLOSED + * - ZC5: Full | BLK_ZONE_FULL + * - ZC6: Read Only | BLK_ZONE_READONLY + * - ZC7: Offline | BLK_ZONE_OFFLINE + * + * Conditions 0x5 to 0xC are reserved by the current ZBC/ZAC spec and should + * be considered invalid. + */ +enum blk_zone_cond { + BLK_ZONE_COND_NOT_WP = 0x0, + BLK_ZONE_COND_EMPTY = 0x1, + BLK_ZONE_COND_IMP_OPEN = 0x2, + BLK_ZONE_COND_EXP_OPEN = 0x3, + BLK_ZONE_COND_CLOSED = 0x4, + BLK_ZONE_COND_READONLY = 0xD, + BLK_ZONE_COND_FULL = 0xE, + BLK_ZONE_COND_OFFLINE = 0xF, +}; + +/** + * struct blk_zone - Zone descriptor for BLKREPORTZONE ioctl. + * + * @start: Zone start in 512 B sector units + * @len: Zone length in 512 B sector units + * @wp: Zone write pointer location in 512 B sector units + * @type: see enum blk_zone_type for possible values + * @cond: see enum blk_zone_cond for possible values + * @non_seq: Flag indicating that the zone is using non-sequential resources + * (for host-aware zoned block devices only). + * @reset: Flag indicating that a zone reset is recommended. + * @reserved: Padding to 64 B to match the ZBC/ZAC defined zone descriptor size. + * + * start, len and wp use the regular 512 B sector unit, regardless of the + * device logical block size. The overall structure size is 64 B to match the + * ZBC/ZAC defined zone descriptor and allow support for future additional + * zone information. + */ +struct blk_zone { + __u64 start; /* Zone start sector */ + __u64 len; /* Zone length in number of sectors */ + __u64 wp; /* Zone write pointer position */ + __u8 type; /* Zone type */ + __u8 cond; /* Zone condition */ + __u8 non_seq; /* Non-sequential write resources active */ + __u8 reset; /* Reset write pointer recommended */ + __u8 reserved[36]; +}; + +#endif /* _UAPI_BLKZONED_H */ -- 2.7.4