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 } 304