diff options
Diffstat (limited to 'drivers/nvme/target/io-cmd.c')
| -rw-r--r-- | drivers/nvme/target/io-cmd.c | 215 |
1 files changed, 215 insertions, 0 deletions
diff --git a/drivers/nvme/target/io-cmd.c b/drivers/nvme/target/io-cmd.c new file mode 100644 index 000000000000..2cd069b691ae --- /dev/null +++ b/drivers/nvme/target/io-cmd.c @@ -0,0 +1,215 @@ +/* + * NVMe I/O command implementation. + * Copyright (c) 2015-2016 HGST, a Western Digital Company. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + */ +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt +#include <linux/blkdev.h> +#include <linux/module.h> +#include "nvmet.h" + +static void nvmet_bio_done(struct bio *bio) +{ + struct nvmet_req *req = bio->bi_private; + + nvmet_req_complete(req, + bio->bi_error ? NVME_SC_INTERNAL | NVME_SC_DNR : 0); + + if (bio != &req->inline_bio) + bio_put(bio); +} + +static inline u32 nvmet_rw_len(struct nvmet_req *req) +{ + return ((u32)le16_to_cpu(req->cmd->rw.length) + 1) << + req->ns->blksize_shift; +} + +static void nvmet_inline_bio_init(struct nvmet_req *req) +{ + struct bio *bio = &req->inline_bio; + + bio_init(bio); + bio->bi_max_vecs = NVMET_MAX_INLINE_BIOVEC; + bio->bi_io_vec = req->inline_bvec; +} + +static void nvmet_execute_rw(struct nvmet_req *req) +{ + int sg_cnt = req->sg_cnt; + struct scatterlist *sg; + struct bio *bio; + sector_t sector; + blk_qc_t cookie; + int op, op_flags = 0, i; + + if (!req->sg_cnt) { + nvmet_req_complete(req, 0); + return; + } + + if (req->cmd->rw.opcode == nvme_cmd_write) { + op = REQ_OP_WRITE; + if (req->cmd->rw.control & cpu_to_le16(NVME_RW_FUA)) + op_flags |= REQ_FUA; + } else { + op = REQ_OP_READ; + } + + sector = le64_to_cpu(req->cmd->rw.slba); + sector <<= (req->ns->blksize_shift - 9); + + nvmet_inline_bio_init(req); + bio = &req->inline_bio; + bio->bi_bdev = req->ns->bdev; + bio->bi_iter.bi_sector = sector; + bio->bi_private = req; + bio->bi_end_io = nvmet_bio_done; + bio_set_op_attrs(bio, op, op_flags); + + for_each_sg(req->sg, sg, req->sg_cnt, i) { + while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset) + != sg->length) { + struct bio *prev = bio; + + bio = bio_alloc(GFP_KERNEL, min(sg_cnt, BIO_MAX_PAGES)); + bio->bi_bdev = req->ns->bdev; + bio->bi_iter.bi_sector = sector; + bio_set_op_attrs(bio, op, op_flags); + + bio_chain(bio, prev); + cookie = submit_bio(prev); + } + + sector += sg->length >> 9; + sg_cnt--; + } + + cookie = submit_bio(bio); + + blk_poll(bdev_get_queue(req->ns->bdev), cookie); +} + +static void nvmet_execute_flush(struct nvmet_req *req) +{ + struct bio *bio; + + nvmet_inline_bio_init(req); + bio = &req->inline_bio; + + bio->bi_bdev = req->ns->bdev; + bio->bi_private = req; + bio->bi_end_io = nvmet_bio_done; + bio_set_op_attrs(bio, REQ_OP_WRITE, WRITE_FLUSH); + + submit_bio(bio); +} + +static u16 nvmet_discard_range(struct nvmet_ns *ns, + struct nvme_dsm_range *range, struct bio **bio) +{ + if (__blkdev_issue_discard(ns->bdev, + le64_to_cpu(range->slba) << (ns->blksize_shift - 9), + le32_to_cpu(range->nlb) << (ns->blksize_shift - 9), + GFP_KERNEL, 0, bio)) + return NVME_SC_INTERNAL | NVME_SC_DNR; + return 0; +} + +static void nvmet_execute_discard(struct nvmet_req *req) +{ + struct nvme_dsm_range range; + struct bio *bio = NULL; + int i; + u16 status; + + for (i = 0; i <= le32_to_cpu(req->cmd->dsm.nr); i++) { + status = nvmet_copy_from_sgl(req, i * sizeof(range), &range, + sizeof(range)); + if (status) + break; + + status = nvmet_discard_range(req->ns, &range, &bio); + if (status) + break; + } + + if (bio) { + bio->bi_private = req; + bio->bi_end_io = nvmet_bio_done; + if (status) { + bio->bi_error = -EIO; + bio_endio(bio); + } else { + submit_bio(bio); + } + } else { + nvmet_req_complete(req, status); + } +} + +static void nvmet_execute_dsm(struct nvmet_req *req) +{ + switch (le32_to_cpu(req->cmd->dsm.attributes)) { + case NVME_DSMGMT_AD: + nvmet_execute_discard(req); + return; + case NVME_DSMGMT_IDR: + case NVME_DSMGMT_IDW: + default: + /* Not supported yet */ + nvmet_req_complete(req, 0); + return; + } +} + +int nvmet_parse_io_cmd(struct nvmet_req *req) +{ + struct nvme_command *cmd = req->cmd; + + if (unlikely(!(req->sq->ctrl->cc & NVME_CC_ENABLE))) { + pr_err("nvmet: got io cmd %d while CC.EN == 0\n", + cmd->common.opcode); + req->ns = NULL; + return NVME_SC_CMD_SEQ_ERROR | NVME_SC_DNR; + } + + if (unlikely(!(req->sq->ctrl->csts & NVME_CSTS_RDY))) { + pr_err("nvmet: got io cmd %d while CSTS.RDY == 0\n", + cmd->common.opcode); + req->ns = NULL; + return NVME_SC_CMD_SEQ_ERROR | NVME_SC_DNR; + } + + req->ns = nvmet_find_namespace(req->sq->ctrl, cmd->rw.nsid); + if (!req->ns) + return NVME_SC_INVALID_NS | NVME_SC_DNR; + + switch (cmd->common.opcode) { + case nvme_cmd_read: + case nvme_cmd_write: + req->execute = nvmet_execute_rw; + req->data_len = nvmet_rw_len(req); + return 0; + case nvme_cmd_flush: + req->execute = nvmet_execute_flush; + req->data_len = 0; + return 0; + case nvme_cmd_dsm: + req->execute = nvmet_execute_dsm; + req->data_len = le32_to_cpu(cmd->dsm.nr) * + sizeof(struct nvme_dsm_range); + return 0; + default: + pr_err("nvmet: unhandled cmd %d\n", cmd->common.opcode); + return NVME_SC_INVALID_OPCODE | NVME_SC_DNR; + } +} |