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

DEFINITIONS

1. nvmet_bdev_set_limits
2. nvmet_bdev_ns_enable
3. nvmet_bdev_ns_disable
4. blk_to_nvme_status
5. nvmet_bio_done
6. nvmet_bdev_execute_rw
7. nvmet_bdev_execute_flush
8. nvmet_bdev_flush
9. nvmet_bdev_discard_range
10. nvmet_bdev_execute_discard
11. nvmet_bdev_execute_dsm
12. nvmet_bdev_execute_write_zeroes
13. nvmet_bdev_parse_io_cmd

   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 void nvmet_bdev_set_limits(struct block_device *bdev, struct nvme_id_ns *id)
  12 {
  13         const struct queue_limits *ql = &bdev_get_queue(bdev)->limits;
  14         /* Number of logical blocks per physical block. */
  15         const u32 lpp = ql->physical_block_size / ql->logical_block_size;
  16         /* Logical blocks per physical block, 0's based. */
  17         const __le16 lpp0b = to0based(lpp);
  18 
  19         /*
  20          * For NVMe 1.2 and later, bit 1 indicates that the fields NAWUN,
  21          * NAWUPF, and NACWU are defined for this namespace and should be
  22          * used by the host for this namespace instead of the AWUN, AWUPF,
  23          * and ACWU fields in the Identify Controller data structure. If
  24          * any of these fields are zero that means that the corresponding
  25          * field from the identify controller data structure should be used.
  26          */
  27         id->nsfeat |= 1 << 1;
  28         id->nawun = lpp0b;
  29         id->nawupf = lpp0b;
  30         id->nacwu = lpp0b;
  31 
  32         /*
  33          * Bit 4 indicates that the fields NPWG, NPWA, NPDG, NPDA, and
  34          * NOWS are defined for this namespace and should be used by
  35          * the host for I/O optimization.
  36          */
  37         id->nsfeat |= 1 << 4;
  38         /* NPWG = Namespace Preferred Write Granularity. 0's based */
  39         id->npwg = lpp0b;
  40         /* NPWA = Namespace Preferred Write Alignment. 0's based */
  41         id->npwa = id->npwg;
  42         /* NPDG = Namespace Preferred Deallocate Granularity. 0's based */
  43         id->npdg = to0based(ql->discard_granularity / ql->logical_block_size);
  44         /* NPDG = Namespace Preferred Deallocate Alignment */
  45         id->npda = id->npdg;
  46         /* NOWS = Namespace Optimal Write Size */
  47         id->nows = to0based(ql->io_opt / ql->logical_block_size);
  48 }
  49 
  50 int nvmet_bdev_ns_enable(struct nvmet_ns *ns)
  51 {
  52         int ret;
  53 
  54         ns->bdev = blkdev_get_by_path(ns->device_path,
  55                         FMODE_READ | FMODE_WRITE, NULL);
  56         if (IS_ERR(ns->bdev)) {
  57                 ret = PTR_ERR(ns->bdev);
  58                 if (ret != -ENOTBLK) {
  59                         pr_err("failed to open block device %s: (%ld)\n",
  60                                         ns->device_path, PTR_ERR(ns->bdev));
  61                 }
  62                 ns->bdev = NULL;
  63                 return ret;
  64         }
  65         ns->size = i_size_read(ns->bdev->bd_inode);
  66         ns->blksize_shift = blksize_bits(bdev_logical_block_size(ns->bdev));
  67         return 0;
  68 }
  69 
  70 void nvmet_bdev_ns_disable(struct nvmet_ns *ns)
  71 {
  72         if (ns->bdev) {
  73                 blkdev_put(ns->bdev, FMODE_WRITE | FMODE_READ);
  74                 ns->bdev = NULL;
  75         }
  76 }
  77 
  78 static u16 blk_to_nvme_status(struct nvmet_req *req, blk_status_t blk_sts)
  79 {
  80         u16 status = NVME_SC_SUCCESS;
  81 
  82         if (likely(blk_sts == BLK_STS_OK))
  83                 return status;
  84         /*
  85          * Right now there exists M : 1 mapping between block layer error
  86          * to the NVMe status code (see nvme_error_status()). For consistency,
  87          * when we reverse map we use most appropriate NVMe Status code from
  88          * the group of the NVMe staus codes used in the nvme_error_status().
  89          */
  90         switch (blk_sts) {
  91         case BLK_STS_NOSPC:
  92                 status = NVME_SC_CAP_EXCEEDED | NVME_SC_DNR;
  93                 req->error_loc = offsetof(struct nvme_rw_command, length);
  94                 break;
  95         case BLK_STS_TARGET:
  96                 status = NVME_SC_LBA_RANGE | NVME_SC_DNR;
  97                 req->error_loc = offsetof(struct nvme_rw_command, slba);
  98                 break;
  99         case BLK_STS_NOTSUPP:
 100                 req->error_loc = offsetof(struct nvme_common_command, opcode);
 101                 switch (req->cmd->common.opcode) {
 102                 case nvme_cmd_dsm:
 103                 case nvme_cmd_write_zeroes:
 104                         status = NVME_SC_ONCS_NOT_SUPPORTED | NVME_SC_DNR;
 105                         break;
 106                 default:
 107                         status = NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
 108                 }
 109                 break;
 110         case BLK_STS_MEDIUM:
 111                 status = NVME_SC_ACCESS_DENIED;
 112                 req->error_loc = offsetof(struct nvme_rw_command, nsid);
 113                 break;
 114         case BLK_STS_IOERR:
 115                 /* fallthru */
 116         default:
 117                 status = NVME_SC_INTERNAL | NVME_SC_DNR;
 118                 req->error_loc = offsetof(struct nvme_common_command, opcode);
 119         }
 120 
 121         switch (req->cmd->common.opcode) {
 122         case nvme_cmd_read:
 123         case nvme_cmd_write:
 124                 req->error_slba = le64_to_cpu(req->cmd->rw.slba);
 125                 break;
 126         case nvme_cmd_write_zeroes:
 127                 req->error_slba =
 128                         le64_to_cpu(req->cmd->write_zeroes.slba);
 129                 break;
 130         default:
 131                 req->error_slba = 0;
 132         }
 133         return status;
 134 }
 135 
 136 static void nvmet_bio_done(struct bio *bio)
 137 {
 138         struct nvmet_req *req = bio->bi_private;
 139 
 140         nvmet_req_complete(req, blk_to_nvme_status(req, bio->bi_status));
 141         if (bio != &req->b.inline_bio)
 142                 bio_put(bio);
 143 }
 144 
 145 static void nvmet_bdev_execute_rw(struct nvmet_req *req)
 146 {
 147         int sg_cnt = req->sg_cnt;
 148         struct bio *bio;
 149         struct scatterlist *sg;
 150         sector_t sector;
 151         int op, op_flags = 0, i;
 152 
 153         if (!req->sg_cnt) {
 154                 nvmet_req_complete(req, 0);
 155                 return;
 156         }
 157 
 158         if (req->cmd->rw.opcode == nvme_cmd_write) {
 159                 op = REQ_OP_WRITE;
 160                 op_flags = REQ_SYNC | REQ_IDLE;
 161                 if (req->cmd->rw.control & cpu_to_le16(NVME_RW_FUA))
 162                         op_flags |= REQ_FUA;
 163         } else {
 164                 op = REQ_OP_READ;
 165         }
 166 
 167         if (is_pci_p2pdma_page(sg_page(req->sg)))
 168                 op_flags |= REQ_NOMERGE;
 169 
 170         sector = le64_to_cpu(req->cmd->rw.slba);
 171         sector <<= (req->ns->blksize_shift - 9);
 172 
 173         if (req->data_len <= NVMET_MAX_INLINE_DATA_LEN) {
 174                 bio = &req->b.inline_bio;
 175                 bio_init(bio, req->inline_bvec, ARRAY_SIZE(req->inline_bvec));
 176         } else {
 177                 bio = bio_alloc(GFP_KERNEL, min(sg_cnt, BIO_MAX_PAGES));
 178         }
 179         bio_set_dev(bio, req->ns->bdev);
 180         bio->bi_iter.bi_sector = sector;
 181         bio->bi_private = req;
 182         bio->bi_end_io = nvmet_bio_done;
 183         bio_set_op_attrs(bio, op, op_flags);
 184 
 185         for_each_sg(req->sg, sg, req->sg_cnt, i) {
 186                 while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset)
 187                                 != sg->length) {
 188                         struct bio *prev = bio;
 189 
 190                         bio = bio_alloc(GFP_KERNEL, min(sg_cnt, BIO_MAX_PAGES));
 191                         bio_set_dev(bio, req->ns->bdev);
 192                         bio->bi_iter.bi_sector = sector;
 193                         bio_set_op_attrs(bio, op, op_flags);
 194 
 195                         bio_chain(bio, prev);
 196                         submit_bio(prev);
 197                 }
 198 
 199                 sector += sg->length >> 9;
 200                 sg_cnt--;
 201         }
 202 
 203         submit_bio(bio);
 204 }
 205 
 206 static void nvmet_bdev_execute_flush(struct nvmet_req *req)
 207 {
 208         struct bio *bio = &req->b.inline_bio;
 209 
 210         bio_init(bio, req->inline_bvec, ARRAY_SIZE(req->inline_bvec));
 211         bio_set_dev(bio, req->ns->bdev);
 212         bio->bi_private = req;
 213         bio->bi_end_io = nvmet_bio_done;
 214         bio->bi_opf = REQ_OP_WRITE | REQ_PREFLUSH;
 215 
 216         submit_bio(bio);
 217 }
 218 
 219 u16 nvmet_bdev_flush(struct nvmet_req *req)
 220 {
 221         if (blkdev_issue_flush(req->ns->bdev, GFP_KERNEL, NULL))
 222                 return NVME_SC_INTERNAL | NVME_SC_DNR;
 223         return 0;
 224 }
 225 
 226 static u16 nvmet_bdev_discard_range(struct nvmet_req *req,
 227                 struct nvme_dsm_range *range, struct bio **bio)
 228 {
 229         struct nvmet_ns *ns = req->ns;
 230         int ret;
 231 
 232         ret = __blkdev_issue_discard(ns->bdev,
 233                         le64_to_cpu(range->slba) << (ns->blksize_shift - 9),
 234                         le32_to_cpu(range->nlb) << (ns->blksize_shift - 9),
 235                         GFP_KERNEL, 0, bio);
 236         if (ret && ret != -EOPNOTSUPP) {
 237                 req->error_slba = le64_to_cpu(range->slba);
 238                 return errno_to_nvme_status(req, ret);
 239         }
 240         return NVME_SC_SUCCESS;
 241 }
 242 
 243 static void nvmet_bdev_execute_discard(struct nvmet_req *req)
 244 {
 245         struct nvme_dsm_range range;
 246         struct bio *bio = NULL;
 247         int i;
 248         u16 status;
 249 
 250         for (i = 0; i <= le32_to_cpu(req->cmd->dsm.nr); i++) {
 251                 status = nvmet_copy_from_sgl(req, i * sizeof(range), &range,
 252                                 sizeof(range));
 253                 if (status)
 254                         break;
 255 
 256                 status = nvmet_bdev_discard_range(req, &range, &bio);
 257                 if (status)
 258                         break;
 259         }
 260 
 261         if (bio) {
 262                 bio->bi_private = req;
 263                 bio->bi_end_io = nvmet_bio_done;
 264                 if (status) {
 265                         bio->bi_status = BLK_STS_IOERR;
 266                         bio_endio(bio);
 267                 } else {
 268                         submit_bio(bio);
 269                 }
 270         } else {
 271                 nvmet_req_complete(req, status);
 272         }
 273 }
 274 
 275 static void nvmet_bdev_execute_dsm(struct nvmet_req *req)
 276 {
 277         switch (le32_to_cpu(req->cmd->dsm.attributes)) {
 278         case NVME_DSMGMT_AD:
 279                 nvmet_bdev_execute_discard(req);
 280                 return;
 281         case NVME_DSMGMT_IDR:
 282         case NVME_DSMGMT_IDW:
 283         default:
 284                 /* Not supported yet */
 285                 nvmet_req_complete(req, 0);
 286                 return;
 287         }
 288 }
 289 
 290 static void nvmet_bdev_execute_write_zeroes(struct nvmet_req *req)
 291 {
 292         struct nvme_write_zeroes_cmd *write_zeroes = &req->cmd->write_zeroes;
 293         struct bio *bio = NULL;
 294         sector_t sector;
 295         sector_t nr_sector;
 296         int ret;
 297 
 298         sector = le64_to_cpu(write_zeroes->slba) <<
 299                 (req->ns->blksize_shift - 9);
 300         nr_sector = (((sector_t)le16_to_cpu(write_zeroes->length) + 1) <<
 301                 (req->ns->blksize_shift - 9));
 302 
 303         ret = __blkdev_issue_zeroout(req->ns->bdev, sector, nr_sector,
 304                         GFP_KERNEL, &bio, 0);
 305         if (bio) {
 306                 bio->bi_private = req;
 307                 bio->bi_end_io = nvmet_bio_done;
 308                 submit_bio(bio);
 309         } else {
 310                 nvmet_req_complete(req, errno_to_nvme_status(req, ret));
 311         }
 312 }
 313 
 314 u16 nvmet_bdev_parse_io_cmd(struct nvmet_req *req)
 315 {
 316         struct nvme_command *cmd = req->cmd;
 317 
 318         switch (cmd->common.opcode) {
 319         case nvme_cmd_read:
 320         case nvme_cmd_write:
 321                 req->execute = nvmet_bdev_execute_rw;
 322                 req->data_len = nvmet_rw_len(req);
 323                 return 0;
 324         case nvme_cmd_flush:
 325                 req->execute = nvmet_bdev_execute_flush;
 326                 req->data_len = 0;
 327                 return 0;
 328         case nvme_cmd_dsm:
 329                 req->execute = nvmet_bdev_execute_dsm;
 330                 req->data_len = (le32_to_cpu(cmd->dsm.nr) + 1) *
 331                         sizeof(struct nvme_dsm_range);
 332                 return 0;
 333         case nvme_cmd_write_zeroes:
 334                 req->execute = nvmet_bdev_execute_write_zeroes;
 335                 req->data_len = 0;
 336                 return 0;
 337         default:
 338                 pr_err("unhandled cmd %d on qid %d\n", cmd->common.opcode,
 339                        req->sq->qid);
 340                 req->error_loc = offsetof(struct nvme_common_command, opcode);
 341                 return NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
 342         }
 343 }