nvmet: add support for the Write Zeroes command

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 <chaitanya.kulkarni@hgst.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
This commit is contained in:
Chaitanya Kulkarni 2016-11-30 12:29:02 -08:00 committed by Jens Axboe
parent 6d31e3ba23
commit d262920998
2 changed files with 31 additions and 1 deletions

View File

@ -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;

View File

@ -170,6 +170,32 @@ 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;
@ -207,6 +233,9 @@ 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;