drivers/nvme/target/io-cmd-bdev.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * NVMe I/O command implementation.
   4  * Copyright (c) 2015-2016 HGST, a Western Digital Company.
   5  */
   6 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
   7 #include <linux/blkdev.h>
   8 #include <linux/module.h>
   9 #include "nvmet.h"
  10
  11 int nvmet_bdev_ns_enable(struct nvmet_ns *ns)
  12 {
  13         int ret;
  14
  15         ns->bdev = blkdev_get_by_path(ns->device_path,
  16                         FMODE_READ | FMODE_WRITE, NULL);
  17         if (IS_ERR(ns->bdev)) {
  18                 ret = PTR_ERR(ns->bdev);
  19                 if (ret != -ENOTBLK) {
  20                         pr_err("failed to open block device %s: (%ld)\n",
  21                                         ns->device_path, PTR_ERR(ns->bdev));
  22                 }
  23                 ns->bdev = NULL;
  24                 return ret;
  25         }
  26         ns->size = i_size_read(ns->bdev->bd_inode);
  27         ns->blksize_shift = blksize_bits(bdev_logical_block_size(ns->bdev));
  28         return 0;
  29 }
  30
  31 void nvmet_bdev_ns_disable(struct nvmet_ns *ns)
  32 {
  33         if (ns->bdev) {
  34                 blkdev_put(ns->bdev, FMODE_WRITE | FMODE_READ);
  35                 ns->bdev = NULL;
  36         }
  37 }
  38
  39 static u16 blk_to_nvme_status(struct nvmet_req *req, blk_status_t blk_sts)
  40 {
  41         u16 status = NVME_SC_SUCCESS;
  42
  43         if (likely(blk_sts == BLK_STS_OK))
  44                 return status;
  45         /*
  46          * Right now there exists M : 1 mapping between block layer error
  47          * to the NVMe status code (see nvme_error_status()). For consistency,
  48          * when we reverse map we use most appropriate NVMe Status code from
  49          * the group of the NVMe staus codes used in the nvme_error_status().
  50          */
  51         switch (blk_sts) {
  52         case BLK_STS_NOSPC:
  53                 status = NVME_SC_CAP_EXCEEDED | NVME_SC_DNR;
  54                 req->error_loc = offsetof(struct nvme_rw_command, length);
  55                 break;
  56         case BLK_STS_TARGET:
  57                 status = NVME_SC_LBA_RANGE | NVME_SC_DNR;
  58                 req->error_loc = offsetof(struct nvme_rw_command, slba);
  59                 break;
  60         case BLK_STS_NOTSUPP:
  61                 req->error_loc = offsetof(struct nvme_common_command, opcode);
  62                 switch (req->cmd->common.opcode) {
  63                 case nvme_cmd_dsm:
  64                 case nvme_cmd_write_zeroes:
  65                         status = NVME_SC_ONCS_NOT_SUPPORTED | NVME_SC_DNR;
  66                         break;
  67                 default:
  68                         status = NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
  69                 }
  70                 break;
  71         case BLK_STS_MEDIUM:
  72                 status = NVME_SC_ACCESS_DENIED;
  73                 req->error_loc = offsetof(struct nvme_rw_command, nsid);
  74                 break;
  75         case BLK_STS_IOERR:
  76                 /* fallthru */
  77         default:
  78                 status = NVME_SC_INTERNAL | NVME_SC_DNR;
  79                 req->error_loc = offsetof(struct nvme_common_command, opcode);
  80         }
  81
  82         switch (req->cmd->common.opcode) {
  83         case nvme_cmd_read:
  84         case nvme_cmd_write:
  85                 req->error_slba = le64_to_cpu(req->cmd->rw.slba);
  86                 break;
  87         case nvme_cmd_write_zeroes:
  88                 req->error_slba =
  89                         le64_to_cpu(req->cmd->write_zeroes.slba);
  90                 break;
  91         default:
  92                 req->error_slba = 0;
  93         }
  94         return status;
  95 }
  96
  97 static void nvmet_bio_done(struct bio *bio)
  98 {
  99         struct nvmet_req *req = bio->bi_private;
 100
 101         nvmet_req_complete(req, blk_to_nvme_status(req, bio->bi_status));
 102         if (bio != &req->b.inline_bio)
 103                 bio_put(bio);
 104 }
 105
 106 static void nvmet_bdev_execute_rw(struct nvmet_req *req)
 107 {
 108         int sg_cnt = req->sg_cnt;
 109         struct bio *bio;
 110         struct scatterlist *sg;
 111         sector_t sector;
 112         int op, op_flags = 0, i;
 113
 114         if (!req->sg_cnt) {
 115                 nvmet_req_complete(req, 0);
 116                 return;
 117         }
 118
 119         if (req->cmd->rw.opcode == nvme_cmd_write) {
 120                 op = REQ_OP_WRITE;
 121                 op_flags = REQ_SYNC | REQ_IDLE;
 122                 if (req->cmd->rw.control & cpu_to_le16(NVME_RW_FUA))
 123                         op_flags |= REQ_FUA;
 124         } else {
 125                 op = REQ_OP_READ;
 126         }
 127
 128         if (is_pci_p2pdma_page(sg_page(req->sg)))
 129                 op_flags |= REQ_NOMERGE;
 130
 131         sector = le64_to_cpu(req->cmd->rw.slba);
 132         sector <<= (req->ns->blksize_shift - 9);
 133
 134         if (req->data_len <= NVMET_MAX_INLINE_DATA_LEN) {
 135                 bio = &req->b.inline_bio;
 136                 bio_init(bio, req->inline_bvec, ARRAY_SIZE(req->inline_bvec));
 137         } else {
 138                 bio = bio_alloc(GFP_KERNEL, min(sg_cnt, BIO_MAX_PAGES));
 139         }
 140         bio_set_dev(bio, req->ns->bdev);
 141         bio->bi_iter.bi_sector = sector;
 142         bio->bi_private = req;
 143         bio->bi_end_io = nvmet_bio_done;
 144         bio_set_op_attrs(bio, op, op_flags);
 145
 146         for_each_sg(req->sg, sg, req->sg_cnt, i) {
 147                 while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset)
 148                                 != sg->length) {
 149                         struct bio *prev = bio;
 150
 151                         bio = bio_alloc(GFP_KERNEL, min(sg_cnt, BIO_MAX_PAGES));
 152                         bio_set_dev(bio, req->ns->bdev);
 153                         bio->bi_iter.bi_sector = sector;
 154                         bio_set_op_attrs(bio, op, op_flags);
 155
 156                         bio_chain(bio, prev);
 157                         submit_bio(prev);
 158                 }
 159
 160                 sector += sg->length >> 9;
 161                 sg_cnt--;
 162         }
 163
 164         submit_bio(bio);
 165 }
 166
 167 static void nvmet_bdev_execute_flush(struct nvmet_req *req)
 168 {
 169         struct bio *bio = &req->b.inline_bio;
 170
 171         bio_init(bio, req->inline_bvec, ARRAY_SIZE(req->inline_bvec));
 172         bio_set_dev(bio, req->ns->bdev);
 173         bio->bi_private = req;
 174         bio->bi_end_io = nvmet_bio_done;
 175         bio->bi_opf = REQ_OP_WRITE | REQ_PREFLUSH;
 176
 177         submit_bio(bio);
 178 }
 179
 180 u16 nvmet_bdev_flush(struct nvmet_req *req)
 181 {
 182         if (blkdev_issue_flush(req->ns->bdev, GFP_KERNEL, NULL))
 183                 return NVME_SC_INTERNAL | NVME_SC_DNR;
 184         return 0;
 185 }
 186
 187 static u16 nvmet_bdev_discard_range(struct nvmet_req *req,
 188                 struct nvme_dsm_range *range, struct bio **bio)
 189 {
 190         struct nvmet_ns *ns = req->ns;
 191         int ret;
 192
 193         ret = __blkdev_issue_discard(ns->bdev,
 194                         le64_to_cpu(range->slba) << (ns->blksize_shift - 9),
 195                         le32_to_cpu(range->nlb) << (ns->blksize_shift - 9),
 196                         GFP_KERNEL, 0, bio);
 197         if (ret && ret != -EOPNOTSUPP) {
 198                 req->error_slba = le64_to_cpu(range->slba);
 199                 return errno_to_nvme_status(req, ret);
 200         }
 201         return NVME_SC_SUCCESS;
 202 }
 203
 204 static void nvmet_bdev_execute_discard(struct nvmet_req *req)
 205 {
 206         struct nvme_dsm_range range;
 207         struct bio *bio = NULL;
 208         int i;
 209         u16 status;
 210
 211         for (i = 0; i <= le32_to_cpu(req->cmd->dsm.nr); i++) {
 212                 status = nvmet_copy_from_sgl(req, i * sizeof(range), &range,
 213                                 sizeof(range));
 214                 if (status)
 215                         break;
 216
 217                 status = nvmet_bdev_discard_range(req, &range, &bio);
 218                 if (status)
 219                         break;
 220         }
 221
 222         if (bio) {
 223                 bio->bi_private = req;
 224                 bio->bi_end_io = nvmet_bio_done;
 225                 if (status) {
 226                         bio->bi_status = BLK_STS_IOERR;
 227                         bio_endio(bio);
 228                 } else {
 229                         submit_bio(bio);
 230                 }
 231         } else {
 232                 nvmet_req_complete(req, status);
 233         }
 234 }
 235
 236 static void nvmet_bdev_execute_dsm(struct nvmet_req *req)
 237 {
 238         switch (le32_to_cpu(req->cmd->dsm.attributes)) {
 239         case NVME_DSMGMT_AD:
 240                 nvmet_bdev_execute_discard(req);
 241                 return;
 242         case NVME_DSMGMT_IDR:
 243         case NVME_DSMGMT_IDW:
 244         default:
 245                 /* Not supported yet */
 246                 nvmet_req_complete(req, 0);
 247                 return;
 248         }
 249 }
 250
 251 static void nvmet_bdev_execute_write_zeroes(struct nvmet_req *req)
 252 {
 253         struct nvme_write_zeroes_cmd *write_zeroes = &req->cmd->write_zeroes;
 254         struct bio *bio = NULL;
 255         sector_t sector;
 256         sector_t nr_sector;
 257         int ret;
 258
 259         sector = le64_to_cpu(write_zeroes->slba) <<
 260                 (req->ns->blksize_shift - 9);
 261         nr_sector = (((sector_t)le16_to_cpu(write_zeroes->length) + 1) <<
 262                 (req->ns->blksize_shift - 9));
 263
 264         ret = __blkdev_issue_zeroout(req->ns->bdev, sector, nr_sector,
 265                         GFP_KERNEL, &bio, 0);
 266         if (bio) {
 267                 bio->bi_private = req;
 268                 bio->bi_end_io = nvmet_bio_done;
 269                 submit_bio(bio);
 270         } else {
 271                 nvmet_req_complete(req, errno_to_nvme_status(req, ret));
 272         }
 273 }
 274
 275 u16 nvmet_bdev_parse_io_cmd(struct nvmet_req *req)
 276 {
 277         struct nvme_command *cmd = req->cmd;
 278
 279         switch (cmd->common.opcode) {
 280         case nvme_cmd_read:
 281         case nvme_cmd_write:
 282                 req->execute = nvmet_bdev_execute_rw;
 283                 req->data_len = nvmet_rw_len(req);
 284                 return 0;
 285         case nvme_cmd_flush:
 286                 req->execute = nvmet_bdev_execute_flush;
 287                 req->data_len = 0;
 288                 return 0;
 289         case nvme_cmd_dsm:
 290                 req->execute = nvmet_bdev_execute_dsm;
 291                 req->data_len = (le32_to_cpu(cmd->dsm.nr) + 1) *
 292                         sizeof(struct nvme_dsm_range);
 293                 return 0;
 294         case nvme_cmd_write_zeroes:
 295                 req->execute = nvmet_bdev_execute_write_zeroes;
 296                 return 0;
 297         default:
 298                 pr_err("unhandled cmd %d on qid %d\n", cmd->common.opcode,
 299                        req->sq->qid);
 300                 req->error_loc = offsetof(struct nvme_common_command, opcode);
 301                 return NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
 302         }
 303 }