[PATCH V7 4/6] nvmet: add ZBD over ZNS backend support
Damien Le Moal
Damien.LeMoal at wdc.com
Tue Dec 15 04:06:33 EST 2020
On 2020/12/15 15:03, Chaitanya Kulkarni wrote:
> NVMe TP 4053 – Zoned Namespaces (ZNS) allows host software to
> communicate with a non-volatile memory subsystem using zones for
> NVMe protocol based controllers. NVMeOF already support the ZNS NVMe
> Protocol compliant devices on the target in the passthru mode. There
> are Generic zoned block devices like Shingled Magnetic Recording (SMR)
> HDDs which are not based on the NVMe protocol.
>
> This patch adds ZNS backend to support the ZBDs for NVMeOF target.
>
> This support includes implementing the new command set NVME_CSI_ZNS,
> adding different command handlers for ZNS command set such as
> NVMe Identify Controller, NVMe Identify Namespace, NVMe Zone Append,
> NVMe Zone Management Send and NVMe Zone Management Receive.
>
> With new command set identifier we also update the target command effects
> logs to reflect the ZNS compliant commands.
>
> Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni at wdc.com>
> ---
> drivers/nvme/target/Makefile | 1 +
> drivers/nvme/target/admin-cmd.c | 26 +++
> drivers/nvme/target/core.c | 1 +
> drivers/nvme/target/io-cmd-bdev.c | 33 ++-
> drivers/nvme/target/nvmet.h | 38 ++++
> drivers/nvme/target/zns.c | 342 ++++++++++++++++++++++++++++++
> 6 files changed, 433 insertions(+), 8 deletions(-)
> create mode 100644 drivers/nvme/target/zns.c
>
> diff --git a/drivers/nvme/target/Makefile b/drivers/nvme/target/Makefile
> index ebf91fc4c72e..9837e580fa7e 100644
> --- a/drivers/nvme/target/Makefile
> +++ b/drivers/nvme/target/Makefile
> @@ -12,6 +12,7 @@ obj-$(CONFIG_NVME_TARGET_TCP) += nvmet-tcp.o
> nvmet-y += core.o configfs.o admin-cmd.o fabrics-cmd.o \
> discovery.o io-cmd-file.o io-cmd-bdev.o
> nvmet-$(CONFIG_NVME_TARGET_PASSTHRU) += passthru.o
> +nvmet-$(CONFIG_BLK_DEV_ZONED) += zns.o
> nvme-loop-y += loop.o
> nvmet-rdma-y += rdma.o
> nvmet-fc-y += fc.o
> diff --git a/drivers/nvme/target/admin-cmd.c b/drivers/nvme/target/admin-cmd.c
> index f4c0f3aca485..6f5279b15aa6 100644
> --- a/drivers/nvme/target/admin-cmd.c
> +++ b/drivers/nvme/target/admin-cmd.c
> @@ -192,6 +192,15 @@ static void nvmet_execute_get_log_cmd_effects_ns(struct nvmet_req *req)
> log->iocs[nvme_cmd_dsm] = cpu_to_le32(1 << 0);
> log->iocs[nvme_cmd_write_zeroes] = cpu_to_le32(1 << 0);
> break;
> + case NVME_CSI_ZNS:
> + if (IS_ENABLED(CONFIG_BLK_DEV_ZONED)) {
> + u32 *iocs = log->iocs;
> +
> + iocs[nvme_cmd_zone_append] = cpu_to_le32(1 << 0);
> + iocs[nvme_cmd_zone_mgmt_send] = cpu_to_le32(1 << 0);
> + iocs[nvme_cmd_zone_mgmt_recv] = cpu_to_le32(1 << 0);
> + }
> + break;
> default:
> status = NVME_SC_INVALID_LOG_PAGE;
> break;
> @@ -614,6 +623,7 @@ static u16 nvmet_copy_ns_identifier(struct nvmet_req *req, u8 type, u8 len,
>
> static void nvmet_execute_identify_desclist(struct nvmet_req *req)
> {
> + u16 nvme_cis_zns = NVME_CSI_ZNS;
> u16 status = 0;
> off_t off = 0;
>
> @@ -638,6 +648,14 @@ static void nvmet_execute_identify_desclist(struct nvmet_req *req)
> if (status)
> goto out;
> }
> + if (IS_ENABLED(CONFIG_BLK_DEV_ZONED)) {
> + if (req->ns->csi == NVME_CSI_ZNS)
> + status = nvmet_copy_ns_identifier(req, NVME_NIDT_CSI,
> + NVME_NIDT_CSI_LEN,
> + &nvme_cis_zns, &off);
> + if (status)
> + goto out;
> + }
>
> if (sg_zero_buffer(req->sg, req->sg_cnt, NVME_IDENTIFY_DATA_SIZE - off,
> off) != NVME_IDENTIFY_DATA_SIZE - off)
> @@ -655,8 +673,16 @@ static void nvmet_execute_identify(struct nvmet_req *req)
> switch (req->cmd->identify.cns) {
> case NVME_ID_CNS_NS:
> return nvmet_execute_identify_ns(req);
> + case NVME_ID_CNS_CS_NS:
> + if (req->cmd->identify.csi == NVME_CSI_ZNS)
> + return nvmet_execute_identify_cns_cs_ns(req);
> + break;
> case NVME_ID_CNS_CTRL:
> return nvmet_execute_identify_ctrl(req);
> + case NVME_ID_CNS_CS_CTRL:
> + if (req->cmd->identify.csi == NVME_CSI_ZNS)
> + return nvmet_execute_identify_cns_cs_ctrl(req);
> + break;
> case NVME_ID_CNS_NS_ACTIVE_LIST:
> return nvmet_execute_identify_nslist(req);
> case NVME_ID_CNS_NS_DESC_LIST:
> diff --git a/drivers/nvme/target/core.c b/drivers/nvme/target/core.c
> index 672e4009f8d6..17a99c7134dc 100644
> --- a/drivers/nvme/target/core.c
> +++ b/drivers/nvme/target/core.c
> @@ -1107,6 +1107,7 @@ static inline u8 nvmet_cc_iocqes(u32 cc)
> static inline bool nvmet_cc_css_check(u8 cc_css)
> {
> switch (cc_css <<= NVME_CC_CSS_SHIFT) {
> + case NVME_CC_CSS_CSI:
> case NVME_CC_CSS_NVM:
> return true;
> default:
> diff --git a/drivers/nvme/target/io-cmd-bdev.c b/drivers/nvme/target/io-cmd-bdev.c
> index 23095bdfce06..6178ef643962 100644
> --- a/drivers/nvme/target/io-cmd-bdev.c
> +++ b/drivers/nvme/target/io-cmd-bdev.c
> @@ -63,6 +63,14 @@ static void nvmet_bdev_ns_enable_integrity(struct nvmet_ns *ns)
> }
> }
>
> +void nvmet_bdev_ns_disable(struct nvmet_ns *ns)
> +{
> + if (ns->bdev) {
> + blkdev_put(ns->bdev, FMODE_WRITE | FMODE_READ);
> + ns->bdev = NULL;
> + }
> +}
> +
> int nvmet_bdev_ns_enable(struct nvmet_ns *ns)
> {
> int ret;
> @@ -86,15 +94,15 @@ int nvmet_bdev_ns_enable(struct nvmet_ns *ns)
> if (IS_ENABLED(CONFIG_BLK_DEV_INTEGRITY_T10))
> nvmet_bdev_ns_enable_integrity(ns);
>
> - return 0;
> -}
> -
> -void nvmet_bdev_ns_disable(struct nvmet_ns *ns)
> -{
> - if (ns->bdev) {
> - blkdev_put(ns->bdev, FMODE_WRITE | FMODE_READ);
> - ns->bdev = NULL;
> + if (IS_ENABLED(CONFIG_BLK_DEV_ZONED) && bdev_is_zoned(ns->bdev)) {
> + if (!nvmet_bdev_zns_enable(ns)) {
> + nvmet_bdev_ns_disable(ns);
> + return -EINVAL;
> + }
> + ns->csi = NVME_CSI_ZNS;
> }
> +
> + return 0;
> }
>
> void nvmet_bdev_ns_revalidate(struct nvmet_ns *ns)
> @@ -448,6 +456,15 @@ u16 nvmet_bdev_parse_io_cmd(struct nvmet_req *req)
> case nvme_cmd_write_zeroes:
> req->execute = nvmet_bdev_execute_write_zeroes;
> return 0;
> + case nvme_cmd_zone_append:
> + req->execute = nvmet_bdev_execute_zone_append;
> + return 0;
> + case nvme_cmd_zone_mgmt_recv:
> + req->execute = nvmet_bdev_execute_zone_mgmt_recv;
> + return 0;
> + case nvme_cmd_zone_mgmt_send:
> + req->execute = nvmet_bdev_execute_zone_mgmt_send;
> + return 0;
> default:
> pr_err("unhandled cmd %d on qid %d\n", cmd->common.opcode,
> req->sq->qid);
> diff --git a/drivers/nvme/target/nvmet.h b/drivers/nvme/target/nvmet.h
> index 476b3cd91c65..7361665585a2 100644
> --- a/drivers/nvme/target/nvmet.h
> +++ b/drivers/nvme/target/nvmet.h
> @@ -252,6 +252,10 @@ struct nvmet_subsys {
> unsigned int admin_timeout;
> unsigned int io_timeout;
> #endif /* CONFIG_NVME_TARGET_PASSTHRU */
> +
> +#ifdef CONFIG_BLK_DEV_ZONED
> + u8 zasl;
> +#endif /* CONFIG_BLK_DEV_ZONED */
> };
>
> static inline struct nvmet_subsys *to_subsys(struct config_item *item)
> @@ -614,4 +618,38 @@ static inline sector_t nvmet_lba_to_sect(struct nvmet_ns *ns, __le64 lba)
> return le64_to_cpu(lba) << (ns->blksize_shift - SECTOR_SHIFT);
> }
>
> +#ifdef CONFIG_BLK_DEV_ZONED
> +bool nvmet_bdev_zns_enable(struct nvmet_ns *ns);
> +void nvmet_execute_identify_cns_cs_ctrl(struct nvmet_req *req);
> +void nvmet_execute_identify_cns_cs_ns(struct nvmet_req *req);
> +void nvmet_bdev_execute_zone_mgmt_recv(struct nvmet_req *req);
> +void nvmet_bdev_execute_zone_mgmt_send(struct nvmet_req *req);
> +void nvmet_bdev_execute_zone_append(struct nvmet_req *req);
> +#else /* CONFIG_BLK_DEV_ZONED */
> +static inline bool nvmet_bdev_zns_enable(struct nvmet_ns *ns)
> +{
> + return false;
> +}
> +static inline void
> +nvmet_execute_identify_cns_cs_ctrl(struct nvmet_req *req)
> +{
> +}
> +static inline void
> +nvmet_execute_identify_cns_cs_ns(struct nvmet_req *req)
> +{
> +}
> +static inline void
> +nvmet_bdev_execute_zone_mgmt_recv(struct nvmet_req *req)
> +{
> +}
> +static inline void
> +nvmet_bdev_execute_zone_mgmt_send(struct nvmet_req *req)
> +{
> +}
> +static inline void
> +nvmet_bdev_execute_zone_append(struct nvmet_req *req)
> +{
> +}
> +#endif /* CONFIG_BLK_DEV_ZONED */
> +
> #endif /* _NVMET_H */
> diff --git a/drivers/nvme/target/zns.c b/drivers/nvme/target/zns.c
> new file mode 100644
> index 000000000000..3981baa647b2
> --- /dev/null
> +++ b/drivers/nvme/target/zns.c
> @@ -0,0 +1,342 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * NVMe ZNS-ZBD command implementation.
> + * Copyright (c) 2020-2021 HGST, a Western Digital Company.
> + */
> +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
> +#include <linux/nvme.h>
> +#include <linux/blkdev.h>
> +#include "nvmet.h"
> +
> +/*
> + * We set the Memory Page Size Minimum (MPSMIN) for target controller to 0
> + * which gets added by 12 in the nvme_enable_ctrl() which results in 2^12 = 4k
> + * as page_shift value. When calculating the ZASL use shift by 12.
> + */
> +#define NVMET_MPSMIN_SHIFT 12
> +
> +static u16 nvmet_bdev_zns_checks(struct nvmet_req *req)
> +{
> + u16 status = NVME_SC_SUCCESS;
> +
> + if (!bdev_is_zoned(req->ns->bdev)) {
> + status = NVME_SC_INVALID_NS | NVME_SC_DNR;
> + goto out;
> + }
> +
> + if (req->cmd->zmr.zra != NVME_ZRA_ZONE_REPORT) {
> + status = NVME_SC_INVALID_FIELD;
> + goto out;
> + }
> +
> + if (req->cmd->zmr.zrasf != NVME_ZRASF_ZONE_REPORT_ALL) {
> + status = NVME_SC_INVALID_FIELD;
> + goto out;
> + }
> +
> + if (req->cmd->zmr.pr != NVME_REPORT_ZONE_PARTIAL)
> + status = NVME_SC_INVALID_FIELD;
> +
> +out:
> + return status;
> +}
> +
> +/*
> + * ZNS related command implementation and helpers.
> + */
> +
> +static inline u8 nvmet_zasl(unsigned int zone_append_sects)
> +{
> + /*
> + * Zone Append Size Limit is the value experessed in the units
> + * of minimum memory page size (i.e. 12) and is reported power of 2.
> + */
> + return ilog2((zone_append_sects << 9) >> NVMET_MPSMIN_SHIFT);
> +}
> +
> +static inline bool nvmet_zns_update_zasl(struct nvmet_ns *ns)
> +{
> + struct request_queue *q = ns->bdev->bd_disk->queue;
> + u8 zasl = nvmet_zasl(queue_max_zone_append_sectors(q));
> +
> + if (ns->subsys->zasl)
> + return ns->subsys->zasl < zasl ? false : true;
> +
> + ns->subsys->zasl = zasl;
> + return true;
> +}
> +
> +
> +static int nvmet_bdev_validate_zns_zones_cb(struct blk_zone *z,
> + unsigned int idx, void *data)
> +{
> + if (z->type == BLK_ZONE_TYPE_CONVENTIONAL)
> + return -EOPNOTSUPP;
> + return 0;
> +}
> +
> +static bool nvmet_bdev_has_conv_zones(struct block_device *bdev)
> +{
> + int ret;
> +
> + if (bdev->bd_disk->queue->conv_zones_bitmap)
> + return true;
> +
> + ret = blkdev_report_zones(bdev, 0, blkdev_nr_zones(bdev->bd_disk),
> + nvmet_bdev_validate_zns_zones_cb, NULL);
> +
> + return ret < 0 ? true : false;
> +}
> +
> +bool nvmet_bdev_zns_enable(struct nvmet_ns *ns)
> +{
> + if (nvmet_bdev_has_conv_zones(ns->bdev))
> + return false;
> +
> + /*
> + * For ZBC and ZAC devices, writes into sequential zones must be aligned
> + * to the device physical block size. So use this value as the logical
> + * block size to avoid errors.
> + */
> + ns->blksize_shift = blksize_bits(bdev_physical_block_size(ns->bdev));
> +
> + if (!nvmet_zns_update_zasl(ns))
> + return false;
> +
> + return !(get_capacity(ns->bdev->bd_disk) &
> + (bdev_zone_sectors(ns->bdev) - 1));
> +}
> +
> +/*
> + * ZNS related Admin and I/O command handlers.
> + */
> +void nvmet_execute_identify_cns_cs_ctrl(struct nvmet_req *req)
> +{
> + u8 zasl = req->sq->ctrl->subsys->zasl;
> + struct nvmet_ctrl *ctrl = req->sq->ctrl;
> + struct nvme_id_ctrl_zns *id;
> + u16 status;
> +
> + id = kzalloc(sizeof(*id), GFP_KERNEL);
> + if (!id) {
> + status = NVME_SC_INTERNAL;
> + goto out;
> + }
> +
> + if (ctrl->ops->get_mdts)
> + id->zasl = min_t(u8, ctrl->ops->get_mdts(ctrl), zasl);
> + else
> + id->zasl = zasl;
> +
> + status = nvmet_copy_to_sgl(req, 0, id, sizeof(*id));
> +
> + kfree(id);
> +out:
> + nvmet_req_complete(req, status);
> +}
> +
> +void nvmet_execute_identify_cns_cs_ns(struct nvmet_req *req)
> +{
> + struct nvme_id_ns_zns *id_zns;
> + u16 status = NVME_SC_SUCCESS;
> + u64 zsze;
> +
> + if (le32_to_cpu(req->cmd->identify.nsid) == NVME_NSID_ALL) {
> + req->error_loc = offsetof(struct nvme_identify, nsid);
> + status = NVME_SC_INVALID_NS | NVME_SC_DNR;
> + goto out;
> + }
> +
> + id_zns = kzalloc(sizeof(*id_zns), GFP_KERNEL);
> + if (!id_zns) {
> + status = NVME_SC_INTERNAL;
> + goto out;
> + }
> +
> + req->ns = nvmet_find_namespace(req->sq->ctrl, req->cmd->identify.nsid);
> + if (!req->ns) {
> + status = NVME_SC_INTERNAL;
> + goto done;
> + }
> +
> + if (!bdev_is_zoned(req->ns->bdev)) {
> + req->error_loc = offsetof(struct nvme_identify, nsid);
> + status = NVME_SC_INVALID_NS | NVME_SC_DNR;
> + goto done;
> + }
> +
> + nvmet_ns_revalidate(req->ns);
> + zsze = (bdev_zone_sectors(req->ns->bdev) << 9) >>
> + req->ns->blksize_shift;
> + id_zns->lbafe[0].zsze = cpu_to_le64(zsze);
> + id_zns->mor = cpu_to_le32(bdev_max_open_zones(req->ns->bdev));
> + id_zns->mar = cpu_to_le32(bdev_max_active_zones(req->ns->bdev));
> +
> +done:
> + status = nvmet_copy_to_sgl(req, 0, id_zns, sizeof(*id_zns));
> + kfree(id_zns);
> +out:
> + nvmet_req_complete(req, status);
> +}
> +
> +struct nvmet_report_zone_data {
> + struct nvmet_ns *ns;
> + struct nvme_zone_report *rz;
> +};
> +
> +static int nvmet_bdev_report_zone_cb(struct blk_zone *z, unsigned int idx,
> + void *data)
> +{
> + struct nvmet_report_zone_data *report_zone_data = data;
> + struct nvme_zone_descriptor *entries = report_zone_data->rz->entries;
> + struct nvmet_ns *ns = report_zone_data->ns;
> +
> + entries[idx].zcap = nvmet_sect_to_lba(ns, z->capacity);
> + entries[idx].zslba = nvmet_sect_to_lba(ns, z->start);
> + entries[idx].wp = nvmet_sect_to_lba(ns, z->wp);
> + entries[idx].za = z->reset ? 1 << 2 : 0;
> + entries[idx].zt = z->type;
> + entries[idx].zs = z->cond << 4;
> +
> + return 0;
> +}
> +
> +void nvmet_bdev_execute_zone_mgmt_recv(struct nvmet_req *req)
> +{
> + sector_t sect = nvmet_lba_to_sect(req->ns, req->cmd->zmr.slba);
> + u32 bufsize = (le32_to_cpu(req->cmd->zmr.numd) + 1) << 2;
> + struct nvmet_report_zone_data data = { .ns = req->ns };
> + unsigned int nr_zones;
> + int reported_zones;
> + u16 status;
> +
> + nr_zones = (bufsize - sizeof(struct nvme_zone_report)) /
> + sizeof(struct nvme_zone_descriptor);
You could move this right before the vmalloc call since it is first used there.
> +
> + status = nvmet_bdev_zns_checks(req);
> + if (status)
> + goto out;
> +
> + data.rz = __vmalloc(bufsize, GFP_KERNEL | __GFP_NORETRY | __GFP_ZERO);
> + if (!data.rz) {
> + status = NVME_SC_INTERNAL;
> + goto out;
> + }
> +
> + reported_zones = blkdev_report_zones(req->ns->bdev, sect, nr_zones,
> + nvmet_bdev_report_zone_cb,
> + &data);
> + if (reported_zones < 0) {
> + status = NVME_SC_INTERNAL;
> + goto out_free_report_zones;
> + }
> +
> + data.rz->nr_zones = cpu_to_le64(reported_zones);
> +
> + status = nvmet_copy_to_sgl(req, 0, data.rz, bufsize);
> +
> +out_free_report_zones:
> + kvfree(data.rz);
> +out:
> + nvmet_req_complete(req, status);
> +}
> +
> +void nvmet_bdev_execute_zone_mgmt_send(struct nvmet_req *req)
> +{
> + sector_t sect = nvmet_lba_to_sect(req->ns, req->cmd->zms.slba);
> + sector_t nr_sect = bdev_zone_sectors(req->ns->bdev);
> + u16 status = NVME_SC_SUCCESS;
> + enum req_opf op;
> + int ret;
> +
> + if (req->cmd->zms.select_all)
> + nr_sect = get_capacity(req->ns->bdev->bd_disk);
> +
> + switch (req->cmd->zms.zsa) {
> + case NVME_ZONE_OPEN:
> + op = REQ_OP_ZONE_OPEN;
> + break;
> + case NVME_ZONE_CLOSE:
> + op = REQ_OP_ZONE_CLOSE;
> + break;
> + case NVME_ZONE_FINISH:
> + op = REQ_OP_ZONE_FINISH;
> + break;
> + case NVME_ZONE_RESET:
> + op = REQ_OP_ZONE_RESET;
> + break;
> + default:
> + status = NVME_SC_INVALID_FIELD;
> + goto out;
> + }
> +
> + ret = blkdev_zone_mgmt(req->ns->bdev, op, sect, nr_sect, GFP_KERNEL);
> + if (ret)
> + status = NVME_SC_INTERNAL;
> +out:
> + nvmet_req_complete(req, status);
> +}
> +
> +void nvmet_bdev_execute_zone_append(struct nvmet_req *req)
> +{
> + sector_t sect = nvmet_lba_to_sect(req->ns, req->cmd->rw.slba);
> + struct request_queue *q = req->ns->bdev->bd_disk->queue;
> + unsigned int max_sects = queue_max_zone_append_sectors(q);
> + u16 status = NVME_SC_SUCCESS;
> + unsigned int total_len = 0;
> + struct scatterlist *sg;
> + int ret = 0, sg_cnt;
> + struct bio *bio;
> +
> + if (!nvmet_check_transfer_len(req, nvmet_rw_data_len(req)))
> + return;
> +
> + if (!req->sg_cnt) {
> + nvmet_req_complete(req, 0);
> + return;
> + }
> +
> + if (req->transfer_len <= NVMET_MAX_INLINE_DATA_LEN) {
> + bio = &req->b.inline_bio;
> + bio_init(bio, req->inline_bvec, ARRAY_SIZE(req->inline_bvec));
> + } else {
> + bio = bio_alloc(GFP_KERNEL, req->sg_cnt);
> + }
> +
> + bio_set_dev(bio, req->ns->bdev);
> + bio->bi_iter.bi_sector = sect;
> + bio->bi_opf = REQ_OP_ZONE_APPEND | REQ_SYNC | REQ_IDLE;
> + if (req->cmd->rw.control & cpu_to_le16(NVME_RW_FUA))
> + bio->bi_opf |= REQ_FUA;
> +
> + for_each_sg(req->sg, sg, req->sg_cnt, sg_cnt) {
> + struct page *p = sg_page(sg);
> + unsigned int l = sg->length;
> + unsigned int o = sg->offset;
> + bool same_page = false;
> +
> + ret = bio_add_hw_page(q, bio, p, l, o, max_sects, &same_page);
> + if (ret != sg->length) {
> + status = NVME_SC_INTERNAL;
> + goto out_bio_put;
> + }
> + if (same_page)
> + put_page(p);
> +
> + total_len += sg->length;
> + }
> +
> + if (total_len != nvmet_rw_data_len(req)) {
> + status = NVME_SC_INTERNAL | NVME_SC_DNR;
> + goto out_bio_put;
> + }
> +
> + ret = submit_bio_wait(bio);
> + req->cqe->result.u64 = nvmet_sect_to_lba(req->ns,
> + bio->bi_iter.bi_sector);
> +
> +out_bio_put:
> + if (bio != &req->b.inline_bio)
> + bio_put(bio);
> + nvmet_req_complete(req, ret < 0 ? NVME_SC_INTERNAL : status);
> +}
Wasn't it the plan to integrate this function into the normal read-write
proccessing ? I remember Christoph commenting on that.
>
--
Damien Le Moal
Western Digital Research
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