drivers/nvme/host/pr.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (c) 2015 Intel Corporation
   4  *      Keith Busch <[email protected]>
   5  */
   6 #include <linux/blkdev.h>
   7 #include <linux/pr.h>
   8 #include <linux/unaligned.h>
   9
  10 #include "nvme.h"
  11
  12 static enum nvme_pr_type nvme_pr_type_from_blk(enum pr_type type)
  13 {
  14         switch (type) {
  15         case PR_WRITE_EXCLUSIVE:
  16                 return NVME_PR_WRITE_EXCLUSIVE;
  17         case PR_EXCLUSIVE_ACCESS:
  18                 return NVME_PR_EXCLUSIVE_ACCESS;
  19         case PR_WRITE_EXCLUSIVE_REG_ONLY:
  20                 return NVME_PR_WRITE_EXCLUSIVE_REG_ONLY;
  21         case PR_EXCLUSIVE_ACCESS_REG_ONLY:
  22                 return NVME_PR_EXCLUSIVE_ACCESS_REG_ONLY;
  23         case PR_WRITE_EXCLUSIVE_ALL_REGS:
  24                 return NVME_PR_WRITE_EXCLUSIVE_ALL_REGS;
  25         case PR_EXCLUSIVE_ACCESS_ALL_REGS:
  26                 return NVME_PR_EXCLUSIVE_ACCESS_ALL_REGS;
  27         }
  28
  29         return 0;
  30 }
  31
  32 static enum pr_type block_pr_type_from_nvme(enum nvme_pr_type type)
  33 {
  34         switch (type) {
  35         case NVME_PR_WRITE_EXCLUSIVE:
  36                 return PR_WRITE_EXCLUSIVE;
  37         case NVME_PR_EXCLUSIVE_ACCESS:
  38                 return PR_EXCLUSIVE_ACCESS;
  39         case NVME_PR_WRITE_EXCLUSIVE_REG_ONLY:
  40                 return PR_WRITE_EXCLUSIVE_REG_ONLY;
  41         case NVME_PR_EXCLUSIVE_ACCESS_REG_ONLY:
  42                 return PR_EXCLUSIVE_ACCESS_REG_ONLY;
  43         case NVME_PR_WRITE_EXCLUSIVE_ALL_REGS:
  44                 return PR_WRITE_EXCLUSIVE_ALL_REGS;
  45         case NVME_PR_EXCLUSIVE_ACCESS_ALL_REGS:
  46                 return PR_EXCLUSIVE_ACCESS_ALL_REGS;
  47         }
  48
  49         return 0;
  50 }
  51
  52 static int nvme_send_ns_head_pr_command(struct block_device *bdev,
  53                 struct nvme_command *c, void *data, unsigned int data_len)
  54 {
  55         struct nvme_ns_head *head = bdev->bd_disk->private_data;
  56         int srcu_idx = srcu_read_lock(&head->srcu);
  57         struct nvme_ns *ns = nvme_find_path(head);
  58         int ret = -EWOULDBLOCK;
  59
  60         if (ns) {
  61                 c->common.nsid = cpu_to_le32(ns->head->ns_id);
  62                 ret = nvme_submit_sync_cmd(ns->queue, c, data, data_len);
  63         }
  64         srcu_read_unlock(&head->srcu, srcu_idx);
  65         return ret;
  66 }
  67
  68 static int nvme_send_ns_pr_command(struct nvme_ns *ns, struct nvme_command *c,
  69                 void *data, unsigned int data_len)
  70 {
  71         c->common.nsid = cpu_to_le32(ns->head->ns_id);
  72         return nvme_submit_sync_cmd(ns->queue, c, data, data_len);
  73 }
  74
  75 static int nvme_status_to_pr_err(int status)
  76 {
  77         if (nvme_is_path_error(status))
  78                 return PR_STS_PATH_FAILED;
  79
  80         switch (status & NVME_SCT_SC_MASK) {
  81         case NVME_SC_SUCCESS:
  82                 return PR_STS_SUCCESS;
  83         case NVME_SC_RESERVATION_CONFLICT:
  84                 return PR_STS_RESERVATION_CONFLICT;
  85         case NVME_SC_ONCS_NOT_SUPPORTED:
  86                 return -EOPNOTSUPP;
  87         case NVME_SC_BAD_ATTRIBUTES:
  88         case NVME_SC_INVALID_OPCODE:
  89         case NVME_SC_INVALID_FIELD:
  90         case NVME_SC_INVALID_NS:
  91                 return -EINVAL;
  92         default:
  93                 return PR_STS_IOERR;
  94         }
  95 }
  96
  97 static int __nvme_send_pr_command(struct block_device *bdev, u32 cdw10,
  98                 u32 cdw11, u8 op, void *data, unsigned int data_len)
  99 {
 100         struct nvme_command c = { 0 };
 101
 102         c.common.opcode = op;
 103         c.common.cdw10 = cpu_to_le32(cdw10);
 104         c.common.cdw11 = cpu_to_le32(cdw11);
 105
 106         if (nvme_disk_is_ns_head(bdev->bd_disk))
 107                 return nvme_send_ns_head_pr_command(bdev, &c, data, data_len);
 108         return nvme_send_ns_pr_command(bdev->bd_disk->private_data, &c,
 109                                 data, data_len);
 110 }
 111
 112 static int nvme_send_pr_command(struct block_device *bdev, u32 cdw10, u32 cdw11,
 113                 u8 op, void *data, unsigned int data_len)
 114 {
 115         int ret;
 116
 117         ret = __nvme_send_pr_command(bdev, cdw10, cdw11, op, data, data_len);
 118         return ret < 0 ? ret : nvme_status_to_pr_err(ret);
 119 }
 120
 121 static int nvme_pr_register(struct block_device *bdev, u64 old_key, u64 new_key,
 122                 unsigned int flags)
 123 {
 124         struct nvmet_pr_register_data data = { 0 };
 125         u32 cdw10;
 126
 127         if (flags & ~PR_FL_IGNORE_KEY)
 128                 return -EOPNOTSUPP;
 129
 130         data.crkey = cpu_to_le64(old_key);
 131         data.nrkey = cpu_to_le64(new_key);
 132
 133         cdw10 = old_key ? NVME_PR_REGISTER_ACT_REPLACE :
 134                 NVME_PR_REGISTER_ACT_REG;
 135         cdw10 |= (flags & PR_FL_IGNORE_KEY) ? NVME_PR_IGNORE_KEY : 0;
 136         cdw10 |= NVME_PR_CPTPL_PERSIST;
 137
 138         return nvme_send_pr_command(bdev, cdw10, 0, nvme_cmd_resv_register,
 139                         &data, sizeof(data));
 140 }
 141
 142 static int nvme_pr_reserve(struct block_device *bdev, u64 key,
 143                 enum pr_type type, unsigned flags)
 144 {
 145         struct nvmet_pr_acquire_data data = { 0 };
 146         u32 cdw10;
 147
 148         if (flags & ~PR_FL_IGNORE_KEY)
 149                 return -EOPNOTSUPP;
 150
 151         data.crkey = cpu_to_le64(key);
 152
 153         cdw10 = NVME_PR_ACQUIRE_ACT_ACQUIRE;
 154         cdw10 |= nvme_pr_type_from_blk(type) << 8;
 155         cdw10 |= (flags & PR_FL_IGNORE_KEY) ? NVME_PR_IGNORE_KEY : 0;
 156
 157         return nvme_send_pr_command(bdev, cdw10, 0, nvme_cmd_resv_acquire,
 158                         &data, sizeof(data));
 159 }
 160
 161 static int nvme_pr_preempt(struct block_device *bdev, u64 old, u64 new,
 162                 enum pr_type type, bool abort)
 163 {
 164         struct nvmet_pr_acquire_data data = { 0 };
 165         u32 cdw10;
 166
 167         data.crkey = cpu_to_le64(old);
 168         data.prkey = cpu_to_le64(new);
 169
 170         cdw10 = abort ? NVME_PR_ACQUIRE_ACT_PREEMPT_AND_ABORT :
 171                         NVME_PR_ACQUIRE_ACT_PREEMPT;
 172         cdw10 |= nvme_pr_type_from_blk(type) << 8;
 173
 174         return nvme_send_pr_command(bdev, cdw10, 0, nvme_cmd_resv_acquire,
 175                         &data, sizeof(data));
 176 }
 177
 178 static int nvme_pr_clear(struct block_device *bdev, u64 key)
 179 {
 180         struct nvmet_pr_release_data data = { 0 };
 181         u32 cdw10;
 182
 183         data.crkey = cpu_to_le64(key);
 184
 185         cdw10 = NVME_PR_RELEASE_ACT_CLEAR;
 186         cdw10 |= key ? 0 : NVME_PR_IGNORE_KEY;
 187
 188         return nvme_send_pr_command(bdev, cdw10, 0, nvme_cmd_resv_release,
 189                         &data, sizeof(data));
 190 }
 191
 192 static int nvme_pr_release(struct block_device *bdev, u64 key, enum pr_type type)
 193 {
 194         struct nvmet_pr_release_data data = { 0 };
 195         u32 cdw10;
 196
 197         data.crkey = cpu_to_le64(key);
 198
 199         cdw10 = NVME_PR_RELEASE_ACT_RELEASE;
 200         cdw10 |= nvme_pr_type_from_blk(type) << 8;
 201         cdw10 |= key ? 0 : NVME_PR_IGNORE_KEY;
 202
 203         return nvme_send_pr_command(bdev, cdw10, 0, nvme_cmd_resv_release,
 204                         &data, sizeof(data));
 205 }
 206
 207 static int nvme_pr_resv_report(struct block_device *bdev, void *data,
 208                 u32 data_len, bool *eds)
 209 {
 210         u32 cdw10, cdw11;
 211         int ret;
 212
 213         cdw10 = nvme_bytes_to_numd(data_len);
 214         cdw11 = NVME_EXTENDED_DATA_STRUCT;
 215         *eds = true;
 216
 217 retry:
 218         ret = __nvme_send_pr_command(bdev, cdw10, cdw11, nvme_cmd_resv_report,
 219                         data, data_len);
 220         if (ret == NVME_SC_HOST_ID_INCONSIST &&
 221             cdw11 == NVME_EXTENDED_DATA_STRUCT) {
 222                 cdw11 = 0;
 223                 *eds = false;
 224                 goto retry;
 225         }
 226
 227         return ret < 0 ? ret : nvme_status_to_pr_err(ret);
 228 }
 229
 230 static int nvme_pr_read_keys(struct block_device *bdev,
 231                 struct pr_keys *keys_info)
 232 {
 233         u32 rse_len, num_keys = keys_info->num_keys;
 234         struct nvme_reservation_status_ext *rse;
 235         int ret, i;
 236         bool eds;
 237
 238         /*
 239          * Assume we are using 128-bit host IDs and allocate a buffer large
 240          * enough to get enough keys to fill the return keys buffer.
 241          */
 242         rse_len = struct_size(rse, regctl_eds, num_keys);
 243         rse = kzalloc(rse_len, GFP_KERNEL);
 244         if (!rse)
 245                 return -ENOMEM;
 246
 247         ret = nvme_pr_resv_report(bdev, rse, rse_len, &eds);
 248         if (ret)
 249                 goto free_rse;
 250
 251         keys_info->generation = le32_to_cpu(rse->gen);
 252         keys_info->num_keys = get_unaligned_le16(&rse->regctl);
 253
 254         num_keys = min(num_keys, keys_info->num_keys);
 255         for (i = 0; i < num_keys; i++) {
 256                 if (eds) {
 257                         keys_info->keys[i] =
 258                                         le64_to_cpu(rse->regctl_eds[i].rkey);
 259                 } else {
 260                         struct nvme_reservation_status *rs;
 261
 262                         rs = (struct nvme_reservation_status *)rse;
 263                         keys_info->keys[i] = le64_to_cpu(rs->regctl_ds[i].rkey);
 264                 }
 265         }
 266
 267 free_rse:
 268         kfree(rse);
 269         return ret;
 270 }
 271
 272 static int nvme_pr_read_reservation(struct block_device *bdev,
 273                 struct pr_held_reservation *resv)
 274 {
 275         struct nvme_reservation_status_ext tmp_rse, *rse;
 276         int ret, i, num_regs;
 277         u32 rse_len;
 278         bool eds;
 279
 280 get_num_regs:
 281         /*
 282          * Get the number of registrations so we know how big to allocate
 283          * the response buffer.
 284          */
 285         ret = nvme_pr_resv_report(bdev, &tmp_rse, sizeof(tmp_rse), &eds);
 286         if (ret)
 287                 return ret;
 288
 289         num_regs = get_unaligned_le16(&tmp_rse.regctl);
 290         if (!num_regs) {
 291                 resv->generation = le32_to_cpu(tmp_rse.gen);
 292                 return 0;
 293         }
 294
 295         rse_len = struct_size(rse, regctl_eds, num_regs);
 296         rse = kzalloc(rse_len, GFP_KERNEL);
 297         if (!rse)
 298                 return -ENOMEM;
 299
 300         ret = nvme_pr_resv_report(bdev, rse, rse_len, &eds);
 301         if (ret)
 302                 goto free_rse;
 303
 304         if (num_regs != get_unaligned_le16(&rse->regctl)) {
 305                 kfree(rse);
 306                 goto get_num_regs;
 307         }
 308
 309         resv->generation = le32_to_cpu(rse->gen);
 310         resv->type = block_pr_type_from_nvme(rse->rtype);
 311
 312         for (i = 0; i < num_regs; i++) {
 313                 if (eds) {
 314                         if (rse->regctl_eds[i].rcsts) {
 315                                 resv->key = le64_to_cpu(rse->regctl_eds[i].rkey);
 316                                 break;
 317                         }
 318                 } else {
 319                         struct nvme_reservation_status *rs;
 320
 321                         rs = (struct nvme_reservation_status *)rse;
 322                         if (rs->regctl_ds[i].rcsts) {
 323                                 resv->key = le64_to_cpu(rs->regctl_ds[i].rkey);
 324                                 break;
 325                         }
 326                 }
 327         }
 328
 329 free_rse:
 330         kfree(rse);
 331         return ret;
 332 }
 333
 334 const struct pr_ops nvme_pr_ops = {
 335         .pr_register    = nvme_pr_register,
 336         .pr_reserve     = nvme_pr_reserve,
 337         .pr_release     = nvme_pr_release,
 338         .pr_preempt     = nvme_pr_preempt,
 339         .pr_clear       = nvme_pr_clear,
 340         .pr_read_keys   = nvme_pr_read_keys,
 341         .pr_read_reservation = nvme_pr_read_reservation,
 342 };