[PATCH v15 08/12] nvmet: add copy command support for bdev and file ns

Nitesh Shetty
2023-09-06T17:55:31Z

Add support for handling nvme_cmd_copy command on target.

For bdev-ns if backing device supports copy offload we call device copy
offload (blkdev_copy_offload).
In case of partial completion from above or absence of device copy offload
capability, we fallback to copy emulation (blkdev_copy_emulation)

For file-ns we call vfs_copy_file_range to service our request.

Currently target always shows copy capability by setting
NVME_CTRL_ONCS_COPY in controller ONCS.

loop target has copy support, which can be used to test copy offload.
trace event support for nvme_cmd_copy.

Signed-off-by: Nitesh Shetty <nj.shetty@samsung.com>
Signed-off-by: Anuj Gupta <anuj20.g@samsung.com>
---
drivers/nvme/target/admin-cmd.c | 9 ++-
drivers/nvme/target/io-cmd-bdev.c | 97 +++++++++++++++++++++++++++++++
drivers/nvme/target/io-cmd-file.c | 50 ++++++++++++++++
drivers/nvme/target/nvmet.h | 4 ++
drivers/nvme/target/trace.c | 19 ++++++
5 files changed, 177 insertions(+), 2 deletions(-)

diff --git a/drivers/nvme/target/admin-cmd.c b/drivers/nvme/target/admin-cmd.c
index 39cb570f833d..4e1a6ca09937 100644
--- a/drivers/nvme/target/admin-cmd.c
+++ b/drivers/nvme/target/admin-cmd.c
@@ -433,8 +433,7 @@ static void nvmet_execute_identify_ctrl(struct nvmet_req *req)
id->nn = cpu_to_le32(NVMET_MAX_NAMESPACES);
id->mnan = cpu_to_le32(NVMET_MAX_NAMESPACES);
id->oncs = cpu_to_le16(NVME_CTRL_ONCS_DSM |
- NVME_CTRL_ONCS_WRITE_ZEROES);
-
+ NVME_CTRL_ONCS_WRITE_ZEROES | NVME_CTRL_ONCS_COPY);
/* XXX: don't report vwc if the underlying device is write through */
id->vwc = NVME_CTRL_VWC_PRESENT;

@@ -536,6 +535,12 @@ static void nvmet_execute_identify_ns(struct nvmet_req *req)

if (req->ns->bdev)
nvmet_bdev_set_limits(req->ns->bdev, id);
+ else {
+ id->msrc = (__force u8)to0based(BIO_MAX_VECS - 1);
+ id->mssrl = cpu_to_le16(BIO_MAX_VECS <<
+ (PAGE_SHIFT - SECTOR_SHIFT));
+ id->mcl = cpu_to_le32(le16_to_cpu(id->mssrl));
+ }

/*
* We just provide a single LBA format that matches what the
diff --git a/drivers/nvme/target/io-cmd-bdev.c b/drivers/nvme/target/io-cmd-bdev.c
index 468833675cc9..444447df9222 100644
--- a/drivers/nvme/target/io-cmd-bdev.c
+++ b/drivers/nvme/target/io-cmd-bdev.c
@@ -46,6 +46,18 @@ void nvmet_bdev_set_limits(struct block_device *bdev, struct nvme_id_ns *id)
id->npda = id->npdg;
/* NOWS = Namespace Optimal Write Size */
id->nows = to0based(bdev_io_opt(bdev) / bdev_logical_block_size(bdev));
+
+ if (bdev_max_copy_sectors(bdev)) {
+ id->msrc = id->msrc;
+ id->mssrl = cpu_to_le16((bdev_max_copy_sectors(bdev) <<
+ SECTOR_SHIFT) / bdev_logical_block_size(bdev));
+ id->mcl = cpu_to_le32((__force u32)id->mssrl);
+ } else {
+ id->msrc = (__force u8)to0based(BIO_MAX_VECS - 1);
+ id->mssrl = cpu_to_le16((BIO_MAX_VECS << PAGE_SHIFT) /
+ bdev_logical_block_size(bdev));
+ id->mcl = cpu_to_le32((__force u32)id->mssrl);
+ }
}

void nvmet_bdev_ns_disable(struct nvmet_ns *ns)
@@ -449,6 +461,87 @@ static void nvmet_bdev_execute_write_zeroes(struct nvmet_req *req)
}
}

+static void nvmet_bdev_copy_emulation_endio(void *private, int status,
+ ssize_t copied)
+{
+ struct nvmet_req *rq = (struct nvmet_req *)private;
+ u16 nvme_status;
+
+ if (rq->copied + copied == rq->copy_len)
+ rq->cqe->result.u32 = cpu_to_le32(1);
+ else
+ rq->cqe->result.u32 = cpu_to_le32(0);
+
+ nvme_status = errno_to_nvme_status(rq, status);
+ nvmet_req_complete(rq, nvme_status);
+}
+
+static void nvmet_bdev_copy_offload_endio(void *private, int status,
+ ssize_t copied)
+{
+ struct nvmet_req *rq = (struct nvmet_req *)private;
+ u16 nvme_status;
+ ssize_t ret;
+
+ if (copied == rq->copy_len) {
+ rq->cqe->result.u32 = cpu_to_le32(1);
+ nvme_status = errno_to_nvme_status(rq, status);
+ } else {
+ rq->copied = copied;
+ ret = blkdev_copy_emulation(rq->ns->bdev, rq->copy_dst + copied,
+ rq->ns->bdev, rq->copy_src + copied,
+ rq->copy_len - copied,
+ nvmet_bdev_copy_emulation_endio,
+ (void *)rq, GFP_KERNEL);
+ if (ret == -EIOCBQUEUED)
+ return;
+ rq->cqe->result.u32 = cpu_to_le32(0);
+ nvme_status = errno_to_nvme_status(rq, status);
+ }
+ nvmet_req_complete(rq, nvme_status);
+}
+
+/*
+ * At present we handle only one range entry, since copy offload is aligned with
+ * copy_file_range, only one entry is passed from block layer.
+ */
+static void nvmet_bdev_execute_copy(struct nvmet_req *rq)
+{
+ struct nvme_copy_range range;
+ struct nvme_command *cmd = rq->cmd;
+ ssize_t ret;
+ u16 status;
+
+ status = nvmet_copy_from_sgl(rq, 0, &range, sizeof(range));
+ if (status)
+ goto err_rq_complete;
+
+ rq->copy_dst = le64_to_cpu(cmd->copy.sdlba) << rq->ns->blksize_shift;
+ rq->copy_src = le64_to_cpu(range.slba) << rq->ns->blksize_shift;
+ rq->copy_len = (range.nlb + 1) << rq->ns->blksize_shift;
+ rq->copied = 0;
+
+ if (bdev_max_copy_sectors(rq->ns->bdev)) {
+ ret = blkdev_copy_offload(rq->ns->bdev, rq->copy_dst,
+ rq->copy_src, rq->copy_len,
+ nvmet_bdev_copy_offload_endio,
+ (void *)rq, GFP_KERNEL);
+ if (ret == -EIOCBQUEUED)
+ return;
+ }
+ ret = blkdev_copy_emulation(rq->ns->bdev, rq->copy_dst, rq->ns->bdev,
+ rq->copy_src, rq->copy_len,
+ nvmet_bdev_copy_emulation_endio, (void *)rq,
+ GFP_KERNEL);
+ if (ret == -EIOCBQUEUED)
+ return;
+
+ rq->cqe->result.u32 = cpu_to_le32(0);
+ status = blk_to_nvme_status(rq, ret);
+err_rq_complete:
+ nvmet_req_complete(rq, status);
+}
+
u16 nvmet_bdev_parse_io_cmd(struct nvmet_req *req)
{
switch (req->cmd->common.opcode) {
@@ -467,6 +560,10 @@ 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_copy:
+ req->execute = nvmet_bdev_execute_copy;
+ return 0;
+
default:
return nvmet_report_invalid_opcode(req);
}
diff --git a/drivers/nvme/target/io-cmd-file.c b/drivers/nvme/target/io-cmd-file.c
index 2d068439b129..4524cfffa4c6 100644
--- a/drivers/nvme/target/io-cmd-file.c
+++ b/drivers/nvme/target/io-cmd-file.c
@@ -322,6 +322,47 @@ static void nvmet_file_dsm_work(struct work_struct *w)
}
}

+static void nvmet_file_copy_work(struct work_struct *w)
+{
+ struct nvmet_req *req = container_of(w, struct nvmet_req, f.work);
+ int nr_range = req->cmd->copy.nr_range + 1;
+ u16 status = 0;
+ int src, id;
+ ssize_t len, ret;
+ loff_t pos;
+
+ pos = le64_to_cpu(req->cmd->copy.sdlba) << req->ns->blksize_shift;
+ if (unlikely(pos + req->transfer_len > req->ns->size)) {
+ nvmet_req_complete(req, errno_to_nvme_status(req, -ENOSPC));
+ return;
+ }
+
+ for (id = 0 ; id < nr_range; id++) {
+ struct nvme_copy_range range;
+
+ status = nvmet_copy_from_sgl(req, id * sizeof(range), &range,
+ sizeof(range));
+ if (status)
+ break;
+
+ src = (le64_to_cpu(range.slba) << (req->ns->blksize_shift));
+ len = (le16_to_cpu(range.nlb) + 1) << (req->ns->blksize_shift);
+ ret = vfs_copy_file_range(req->ns->file, src, req->ns->file,
+ pos, len, 0);
+ pos += ret;
+ if (ret != len) {
+ req->cqe->result.u32 = cpu_to_le32(id);
+ if (ret < 0)
+ status = errno_to_nvme_status(req, ret);
+ else
+ status = errno_to_nvme_status(req, -EIO);
+ break;
+ }
+ }
+
+ nvmet_req_complete(req, status);
+}
+
static void nvmet_file_execute_dsm(struct nvmet_req *req)
{
if (!nvmet_check_data_len_lte(req, nvmet_dsm_len(req)))
@@ -330,6 +371,12 @@ static void nvmet_file_execute_dsm(struct nvmet_req *req)
queue_work(nvmet_wq, &req->f.work);
}

+static void nvmet_file_execute_copy(struct nvmet_req *req)
+{
+ INIT_WORK(&req->f.work, nvmet_file_copy_work);
+ queue_work(nvmet_wq, &req->f.work);
+}
+
static void nvmet_file_write_zeroes_work(struct work_struct *w)
{
struct nvmet_req *req = container_of(w, struct nvmet_req, f.work);
@@ -376,6 +423,9 @@ u16 nvmet_file_parse_io_cmd(struct nvmet_req *req)
case nvme_cmd_write_zeroes:
req->execute = nvmet_file_execute_write_zeroes;
return 0;
+ case nvme_cmd_copy:
+ req->execute = nvmet_file_execute_copy;
+ return 0;
default:
return nvmet_report_invalid_opcode(req);
}
diff --git a/drivers/nvme/target/nvmet.h b/drivers/nvme/target/nvmet.h
index 8cfd60f3b564..42aa7bac6f7a 100644
--- a/drivers/nvme/target/nvmet.h
+++ b/drivers/nvme/target/nvmet.h
@@ -393,6 +393,10 @@ struct nvmet_req {
struct device *p2p_client;
u16 error_loc;
u64 error_slba;
+ off_t copy_dst;
+ off_t copy_src;
+ size_t copy_len;
+ size_t copied;
};

#define NVMET_MAX_MPOOL_BVEC 16
diff --git a/drivers/nvme/target/trace.c b/drivers/nvme/target/trace.c
index bff454d46255..551fdf029381 100644
--- a/drivers/nvme/target/trace.c
+++ b/drivers/nvme/target/trace.c
@@ -92,6 +92,23 @@ static const char *nvmet_trace_dsm(struct trace_seq *p, u8 *cdw10)
return ret;
}

+static const char *nvmet_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=1x%x, dsmgmt=%u, reftag=%u",
+ sdlba, nr_range, control, dsmgmt, reftag);
+ trace_seq_putc(p, 0);
+
+ return ret;
+}
+
static const char *nvmet_trace_common(struct trace_seq *p, u8 *cdw10)
{
const char *ret = trace_seq_buffer_ptr(p);
@@ -129,6 +146,8 @@ const char *nvmet_trace_parse_nvm_cmd(struct trace_seq *p,
return nvmet_trace_read_write(p, cdw10);
case nvme_cmd_dsm:
return nvmet_trace_dsm(p, cdw10);
+ case nvme_cmd_copy:
+ return nvmet_trace_copy(p, cdw10);
default:
return nvmet_trace_common(p, cdw10);
}
--
2.35.1.500.gb896f729e2