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green245.sa.corp.samsungelectronics.net (unknown [107.99.41.245]) by epsmtip2.samsung.com (KnoxPortal) with ESMTPA id 20231222062153epsmtip2458d39b115507ab8971489f478b6b9ab~jEyBP8YTh0362603626epsmtip2S; Fri, 22 Dec 2023 06:21:53 +0000 (GMT) From: Nitesh Shetty To: Jens Axboe , Jonathan Corbet , Alasdair Kergon , Mike Snitzer , Mikulas Patocka , dm-devel@lists.linux.dev, Keith Busch , Christoph Hellwig , Sagi Grimberg , Chaitanya Kulkarni , Alexander Viro , Christian Brauner Cc: martin.petersen@oracle.com, linux-scsi@vger.kernel.org, nitheshshetty@gmail.com, anuj1072538@gmail.com, gost.dev@samsung.com, mcgrof@kernel.org, Nitesh Shetty , Hannes Reinecke , Kanchan Joshi , =?utf-8?q?Javier_Gonz=C3=A1lez?= , Anuj Gupta , linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-nvme@lists.infradead.org, linux-fsdevel@vger.kernel.org Subject: [PATCH v19 07/12] nvme: add copy offload support Date: Fri, 22 Dec 2023 11:43:01 +0530 Message-Id: <20231222061313.12260-8-nj.shetty@samsung.com> X-Mailer: git-send-email 2.35.1.500.gb896f729e2 In-Reply-To: <20231222061313.12260-1-nj.shetty@samsung.com> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Brightmail-Tracker: H4sIAAAAAAAAA01Ta1ATVxTu3d1sAjW6RqsXRGViW6oIJBrojQh1xNZtYRg6Hdsp0ykNZAUE kjQPseIUkIcahrcohKIIaUVAUaCUp5WXUaBSyxAaKiA1VBGpAlVnQKSEQOu/75zvfPd859w5 HJz3PdueEy5TM0qZJJJP2hI1rZudXLI8kxjBT+MYqui4jqOJpzMEOpoxi6OygXQSjbVOAmS+ dgygwqICApmu1WGosSgLQxfK2jF0784UG7XPjZMoq8UI0EivDkNN/c7oXLKeQI1NNwnUU/8d ic7+MMJGKX21JDpveImh3zNGAMo83ouhWnM8QDUzZ3F0aewxgW70r0PdswbWLge6TjfAprsH rxB0zy8aurL0BElX6WPpB1V5gG4wxZF0cVo2i05N+JukJ0b6Cfrx1V6STqsuBXRVZww9VbmB rjSPYwErAiN2hjESKaN0ZGQhcmm4LNSL7/tJkE+Qu4dA6CIUo3f5jjJJFOPF3+MX4PJBeOT8 cviOByWRmvlUgESl4rt571TKNWrGMUyuUnvxGYU0UiFSuKokUSqNLNRVxqh3CAWCbe7zhV9F hL34Q6HQ+x1qLvyVHQfKvLXAhgMpEWyMP0FqgS2HRzUA+PPJM4Q1mARwurkGWINnAP6VocWW 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We receive a request with REQ_OP_COPY_DST. Parse this request which consists of dst(1st) and src(2nd) bios. Form a copy command (TP 4065) trace event support for nvme_copy_cmd. Set the device copy limits to queue limits. Reviewed-by: Hannes Reinecke Signed-off-by: Kanchan Joshi Signed-off-by: Nitesh Shetty Signed-off-by: Javier González Signed-off-by: Anuj Gupta --- drivers/nvme/host/constants.c | 1 + drivers/nvme/host/core.c | 79 +++++++++++++++++++++++++++++++++++ drivers/nvme/host/trace.c | 19 +++++++++ include/linux/blkdev.h | 1 + include/linux/nvme.h | 43 +++++++++++++++++-- 5 files changed, 140 insertions(+), 3 deletions(-) diff --git a/drivers/nvme/host/constants.c b/drivers/nvme/host/constants.c index 20f46c230885..2f504a2b1fe8 100644 --- a/drivers/nvme/host/constants.c +++ b/drivers/nvme/host/constants.c @@ -19,6 +19,7 @@ static const char * const nvme_ops[] = { [nvme_cmd_resv_report] = "Reservation Report", [nvme_cmd_resv_acquire] = "Reservation Acquire", [nvme_cmd_resv_release] = "Reservation Release", + [nvme_cmd_copy] = "Copy Offload", [nvme_cmd_zone_mgmt_send] = "Zone Management Send", [nvme_cmd_zone_mgmt_recv] = "Zone Management Receive", [nvme_cmd_zone_append] = "Zone Append", diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c index 8ebdfd623e0f..c398546e4edc 100644 --- a/drivers/nvme/host/core.c +++ b/drivers/nvme/host/core.c @@ -765,6 +765,63 @@ static inline void nvme_setup_flush(struct nvme_ns *ns, cmnd->common.nsid = cpu_to_le32(ns->head->ns_id); } +static inline blk_status_t nvme_setup_copy_offload(struct nvme_ns *ns, + struct request *req, + struct nvme_command *cmnd) +{ + struct nvme_copy_range *range = NULL; + struct bio *bio; + u64 dst_lba = 0, src_lba = 0, n_lba = 0; + u16 nr_range = 1, control = 0, seg = 1; + + if (blk_rq_nr_phys_segments(req) != BLK_COPY_MAX_SEGMENTS) + return BLK_STS_IOERR; + + /* + * First bio contains information about destination and last bio + * contains information about source. + */ + __rq_for_each_bio(bio, req) { + if (seg == blk_rq_nr_phys_segments(req)) { + src_lba = nvme_sect_to_lba(ns, bio->bi_iter.bi_sector); + if (n_lba != bio->bi_iter.bi_size >> ns->lba_shift) + return BLK_STS_IOERR; + } else { + dst_lba = nvme_sect_to_lba(ns, bio->bi_iter.bi_sector); + n_lba = bio->bi_iter.bi_size >> ns->lba_shift; + } + seg++; + } + + if (req->cmd_flags & REQ_FUA) + control |= NVME_RW_FUA; + + if (req->cmd_flags & REQ_FAILFAST_DEV) + control |= NVME_RW_LR; + + memset(cmnd, 0, sizeof(*cmnd)); + cmnd->copy.opcode = nvme_cmd_copy; + cmnd->copy.nsid = cpu_to_le32(ns->head->ns_id); + cmnd->copy.control = cpu_to_le16(control); + cmnd->copy.sdlba = cpu_to_le64(dst_lba); + cmnd->copy.nr_range = 0; + + range = kmalloc_array(nr_range, sizeof(*range), + GFP_ATOMIC | __GFP_NOWARN); + if (!range) + return BLK_STS_RESOURCE; + + range[0].slba = cpu_to_le64(src_lba); + range[0].nlb = cpu_to_le16(n_lba - 1); + + req->special_vec.bv_page = virt_to_page(range); + req->special_vec.bv_offset = offset_in_page(range); + req->special_vec.bv_len = sizeof(*range) * nr_range; + req->rq_flags |= RQF_SPECIAL_PAYLOAD; + + return BLK_STS_OK; +} + static blk_status_t nvme_setup_discard(struct nvme_ns *ns, struct request *req, struct nvme_command *cmnd) { @@ -1007,6 +1064,11 @@ blk_status_t nvme_setup_cmd(struct nvme_ns *ns, struct request *req) case REQ_OP_ZONE_APPEND: ret = nvme_setup_rw(ns, req, cmd, nvme_cmd_zone_append); break; + case REQ_OP_COPY_DST: + ret = nvme_setup_copy_offload(ns, req, cmd); + break; + case REQ_OP_COPY_SRC: + return BLK_STS_IOERR; default: WARN_ON_ONCE(1); return BLK_STS_IOERR; @@ -1758,6 +1820,21 @@ static void nvme_config_discard(struct gendisk *disk, struct nvme_ns *ns) blk_queue_max_write_zeroes_sectors(queue, UINT_MAX); } +static void nvme_config_copy(struct gendisk *disk, struct nvme_ns *ns, + struct nvme_id_ns *id) +{ + struct nvme_ctrl *ctrl = ns->ctrl; + struct request_queue *q = disk->queue; + + if (!(ctrl->oncs & NVME_CTRL_ONCS_COPY)) { + blk_queue_max_copy_hw_sectors(q, 0); + return; + } + + blk_queue_max_copy_hw_sectors(q, nvme_lba_to_sect(ns, + le16_to_cpu(id->mssrl))); +} + static bool nvme_ns_ids_equal(struct nvme_ns_ids *a, struct nvme_ns_ids *b) { return uuid_equal(&a->uuid, &b->uuid) && @@ -1961,6 +2038,7 @@ static void nvme_update_disk_info(struct gendisk *disk, set_capacity_and_notify(disk, capacity); nvme_config_discard(disk, ns); + nvme_config_copy(disk, ns, id); blk_queue_max_write_zeroes_sectors(disk->queue, ns->ctrl->max_zeroes_sectors); } @@ -4708,6 +4786,7 @@ static inline void _nvme_check_size(void) BUILD_BUG_ON(sizeof(struct nvme_download_firmware) != 64); BUILD_BUG_ON(sizeof(struct nvme_format_cmd) != 64); BUILD_BUG_ON(sizeof(struct nvme_dsm_cmd) != 64); + BUILD_BUG_ON(sizeof(struct nvme_copy_command) != 64); BUILD_BUG_ON(sizeof(struct nvme_write_zeroes_cmd) != 64); BUILD_BUG_ON(sizeof(struct nvme_abort_cmd) != 64); BUILD_BUG_ON(sizeof(struct nvme_get_log_page_command) != 64); diff --git a/drivers/nvme/host/trace.c b/drivers/nvme/host/trace.c index 1c36fcedea20..82c6aef77c31 100644 --- a/drivers/nvme/host/trace.c +++ b/drivers/nvme/host/trace.c @@ -150,6 +150,23 @@ static const char *nvme_trace_read_write(struct trace_seq *p, u8 *cdw10) return ret; } +static const char *nvme_trace_copy(struct trace_seq *p, u8 *cdw10) +{ + const char *ret = trace_seq_buffer_ptr(p); + u64 sdlba = get_unaligned_le64(cdw10); + u8 nr_range = get_unaligned_le16(cdw10 + 8); + u16 control = get_unaligned_le16(cdw10 + 10); + u32 dsmgmt = get_unaligned_le32(cdw10 + 12); + u32 reftag = get_unaligned_le32(cdw10 + 16); + + trace_seq_printf(p, + "sdlba=%llu, nr_range=%u, ctrl=0x%x, dsmgmt=%u, reftag=%u", + sdlba, nr_range, control, dsmgmt, reftag); + trace_seq_putc(p, 0); + + return ret; +} + static const char *nvme_trace_dsm(struct trace_seq *p, u8 *cdw10) { const char *ret = trace_seq_buffer_ptr(p); @@ -243,6 +260,8 @@ const char *nvme_trace_parse_nvm_cmd(struct trace_seq *p, return nvme_trace_zone_mgmt_send(p, cdw10); case nvme_cmd_zone_mgmt_recv: return nvme_trace_zone_mgmt_recv(p, cdw10); + case nvme_cmd_copy: + return nvme_trace_copy(p, cdw10); default: return nvme_trace_common(p, cdw10); } diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 80867c9fd602..24016fbcd409 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1226,6 +1226,7 @@ static inline unsigned int bdev_discard_granularity(struct block_device *bdev) /* maximum copy offload length, this is set to 128MB based on current testing */ #define BLK_COPY_MAX_BYTES (1 << 27) +#define BLK_COPY_MAX_SEGMENTS 2 static inline unsigned int bdev_max_copy_sectors(struct block_device *bdev) { diff --git a/include/linux/nvme.h b/include/linux/nvme.h index 44325c068b6a..4afd2cd1a629 100644 --- a/include/linux/nvme.h +++ b/include/linux/nvme.h @@ -344,7 +344,7 @@ struct nvme_id_ctrl { __u8 nvscc; __u8 nwpc; __le16 acwu; - __u8 rsvd534[2]; + __le16 ocfs; __le32 sgls; __le32 mnan; __u8 rsvd544[224]; @@ -372,6 +372,7 @@ enum { NVME_CTRL_ONCS_WRITE_ZEROES = 1 << 3, NVME_CTRL_ONCS_RESERVATIONS = 1 << 5, NVME_CTRL_ONCS_TIMESTAMP = 1 << 6, + NVME_CTRL_ONCS_COPY = 1 << 8, NVME_CTRL_VWC_PRESENT = 1 << 0, NVME_CTRL_OACS_SEC_SUPP = 1 << 0, NVME_CTRL_OACS_NS_MNGT_SUPP = 1 << 3, @@ -421,7 +422,10 @@ struct nvme_id_ns { __le16 npdg; __le16 npda; __le16 nows; - __u8 rsvd74[18]; + __le16 mssrl; + __le32 mcl; + __u8 msrc; + __u8 rsvd91[11]; __le32 anagrpid; __u8 rsvd96[3]; __u8 nsattr; @@ -838,6 +842,7 @@ enum nvme_opcode { nvme_cmd_resv_report = 0x0e, nvme_cmd_resv_acquire = 0x11, nvme_cmd_resv_release = 0x15, + nvme_cmd_copy = 0x19, nvme_cmd_zone_mgmt_send = 0x79, nvme_cmd_zone_mgmt_recv = 0x7a, nvme_cmd_zone_append = 0x7d, @@ -861,7 +866,8 @@ enum nvme_opcode { nvme_opcode_name(nvme_cmd_resv_release), \ nvme_opcode_name(nvme_cmd_zone_mgmt_send), \ nvme_opcode_name(nvme_cmd_zone_mgmt_recv), \ - nvme_opcode_name(nvme_cmd_zone_append)) + nvme_opcode_name(nvme_cmd_zone_append), \ + nvme_opcode_name(nvme_cmd_copy)) @@ -1038,6 +1044,36 @@ struct nvme_dsm_range { __le64 slba; }; +struct nvme_copy_command { + __u8 opcode; + __u8 flags; + __u16 command_id; + __le32 nsid; + __u64 rsvd2; + __le64 metadata; + union nvme_data_ptr dptr; + __le64 sdlba; + __u8 nr_range; + __u8 rsvd12; + __le16 control; + __le16 rsvd13; + __le16 dspec; + __le32 ilbrt; + __le16 lbat; + __le16 lbatm; +}; + +struct nvme_copy_range { + __le64 rsvd0; + __le64 slba; + __le16 nlb; + __le16 rsvd18; + __le32 rsvd20; + __le32 eilbrt; + __le16 elbat; + __le16 elbatm; +}; + struct nvme_write_zeroes_cmd { __u8 opcode; __u8 flags; @@ -1802,6 +1838,7 @@ struct nvme_command { struct nvme_download_firmware dlfw; struct nvme_format_cmd format; struct nvme_dsm_cmd dsm; + struct nvme_copy_command copy; struct nvme_write_zeroes_cmd write_zeroes; struct nvme_zone_mgmt_send_cmd zms; struct nvme_zone_mgmt_recv_cmd zmr;