[PATCH V2 5/5] nvmet: add support for the Write Zeroes command
From: Chaitanya Kulkarni <hidden>
Date: 2016-11-30 20:29:34
Also in:
linux-nvme
Subsystem:
nvm express target driver, the rest · Maintainers:
Christoph Hellwig, Sagi Grimberg, Chaitanya Kulkarni, Linus Torvalds
Add support for handling write zeroes command on target. Call into __blkdev_issue_zeroout, which the block layer expands into the best suitable variant of zeroing the LBAs. Allow write zeroes operation to deallocate the LBAs when calling __blkdev_issue_zeroout. Signed-off-by: Chaitanya Kulkarni <redacted> --- drivers/nvme/target/admin-cmd.c | 3 ++- drivers/nvme/target/io-cmd.c | 29 +++++++++++++++++++++++++++++ 2 files changed, 31 insertions(+), 1 deletion(-)
diff --git a/drivers/nvme/target/admin-cmd.c b/drivers/nvme/target/admin-cmd.c
index 6fe4c48..ec1ad2a 100644
--- a/drivers/nvme/target/admin-cmd.c
+++ b/drivers/nvme/target/admin-cmd.c@@ -237,7 +237,8 @@ static void nvmet_execute_identify_ctrl(struct nvmet_req *req) id->maxcmd = cpu_to_le16(NVMET_MAX_CMD); id->nn = cpu_to_le32(ctrl->subsys->max_nsid); - id->oncs = cpu_to_le16(NVME_CTRL_ONCS_DSM); + id->oncs = cpu_to_le16(NVME_CTRL_ONCS_DSM | + NVME_CTRL_ONCS_WRITE_ZEROES); /* XXX: don't report vwc if the underlying device is write through */ id->vwc = NVME_CTRL_VWC_PRESENT;
diff --git a/drivers/nvme/target/io-cmd.c b/drivers/nvme/target/io-cmd.c
index ef52b1e..b3d21b0 100644
--- a/drivers/nvme/target/io-cmd.c
+++ b/drivers/nvme/target/io-cmd.c@@ -172,6 +172,32 @@ static void nvmet_execute_dsm(struct nvmet_req *req) } } +static void nvmet_execute_write_zeroes(struct nvmet_req *req) +{ + struct nvme_write_zeroes_cmd *write_zeroes = &req->cmd->write_zeroes; + struct bio *bio = NULL; + u16 status = NVME_SC_SUCCESS; + sector_t sector; + sector_t nr_sector; + + sector = le64_to_cpu(write_zeroes->slba) << + (req->ns->blksize_shift - 9); + nr_sector = (((sector_t)le32_to_cpu(write_zeroes->length)) << + (req->ns->blksize_shift - 9)) + 1; + + if (__blkdev_issue_zeroout(req->ns->bdev, sector, nr_sector, + GFP_KERNEL, &bio, true)) + status = NVME_SC_INTERNAL | NVME_SC_DNR; + + if (bio) { + bio->bi_private = req; + bio->bi_end_io = nvmet_bio_done; + submit_bio(bio); + } else { + nvmet_req_complete(req, status); + } +} + int nvmet_parse_io_cmd(struct nvmet_req *req) { struct nvme_command *cmd = req->cmd;
@@ -209,6 +235,9 @@ int nvmet_parse_io_cmd(struct nvmet_req *req) req->data_len = le32_to_cpu(cmd->dsm.nr + 1) * sizeof(struct nvme_dsm_range); return 0; + case nvme_cmd_write_zeroes: + req->execute = nvmet_execute_write_zeroes; + return 0; default: pr_err("nvmet: unhandled cmd %d\n", cmd->common.opcode); return NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
--
1.8.3.1