drivers/nvme/host/pr.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (c) 2015 Intel Corporation
   4  *      Keith Busch <kbusch@kernel.org>
   5  */
   6 #include <linux/blkdev.h>
   7 #include <linux/pr.h>
   8 #include <asm/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_sc_to_pr_err(int nvme_sc)
  76 {
  77         if (nvme_is_path_error(nvme_sc))
  78                 return PR_STS_PATH_FAILED;
  79
  80         switch (nvme_sc) {
  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,
  98                 struct nvme_command *c, void *data, unsigned int data_len)
  99 {
 100         if (IS_ENABLED(CONFIG_NVME_MULTIPATH) &&
 101             nvme_disk_is_ns_head(bdev->bd_disk))
 102                 return nvme_send_ns_head_pr_command(bdev, c, data, data_len);
 103
 104         return nvme_send_ns_pr_command(bdev->bd_disk->private_data, c, data,
 105                                        data_len);
 106 }
 107
 108 static int nvme_pr_command(struct block_device *bdev, u32 cdw10,
 109                                 u64 key, u64 sa_key, u8 op)
 110 {
 111         struct nvme_command c = { };
 112         u8 data[16] = { 0, };
 113         int ret;
 114
 115         put_unaligned_le64(key, &data[0]);
 116         put_unaligned_le64(sa_key, &data[8]);
 117
 118         c.common.opcode = op;
 119         c.common.cdw10 = cpu_to_le32(cdw10);
 120
 121         ret = nvme_send_pr_command(bdev, &c, data, sizeof(data));
 122         if (ret < 0)
 123                 return ret;
 124
 125         return nvme_sc_to_pr_err(ret);
 126 }
 127
 128 static int nvme_pr_register(struct block_device *bdev, u64 old,
 129                 u64 new, unsigned flags)
 130 {
 131         u32 cdw10;
 132
 133         if (flags & ~PR_FL_IGNORE_KEY)
 134                 return -EOPNOTSUPP;
 135
 136         cdw10 = old ? 2 : 0;
 137         cdw10 |= (flags & PR_FL_IGNORE_KEY) ? 1 << 3 : 0;
 138         cdw10 |= (1 << 30) | (1 << 31); /* PTPL=1 */
 139         return nvme_pr_command(bdev, cdw10, old, new, nvme_cmd_resv_register);
 140 }
 141
 142 static int nvme_pr_reserve(struct block_device *bdev, u64 key,
 143                 enum pr_type type, unsigned flags)
 144 {
 145         u32 cdw10;
 146
 147         if (flags & ~PR_FL_IGNORE_KEY)
 148                 return -EOPNOTSUPP;
 149
 150         cdw10 = nvme_pr_type_from_blk(type) << 8;
 151         cdw10 |= ((flags & PR_FL_IGNORE_KEY) ? 1 << 3 : 0);
 152         return nvme_pr_command(bdev, cdw10, key, 0, nvme_cmd_resv_acquire);
 153 }
 154
 155 static int nvme_pr_preempt(struct block_device *bdev, u64 old, u64 new,
 156                 enum pr_type type, bool abort)
 157 {
 158         u32 cdw10 = nvme_pr_type_from_blk(type) << 8 | (abort ? 2 : 1);
 159
 160         return nvme_pr_command(bdev, cdw10, old, new, nvme_cmd_resv_acquire);
 161 }
 162
 163 static int nvme_pr_clear(struct block_device *bdev, u64 key)
 164 {
 165         u32 cdw10 = 1 | (key ? 0 : 1 << 3);
 166
 167         return nvme_pr_command(bdev, cdw10, key, 0, nvme_cmd_resv_release);
 168 }
 169
 170 static int nvme_pr_release(struct block_device *bdev, u64 key, enum pr_type type)
 171 {
 172         u32 cdw10 = nvme_pr_type_from_blk(type) << 8 | (key ? 0 : 1 << 3);
 173
 174         return nvme_pr_command(bdev, cdw10, key, 0, nvme_cmd_resv_release);
 175 }
 176
 177 static int nvme_pr_resv_report(struct block_device *bdev, void *data,
 178                 u32 data_len, bool *eds)
 179 {
 180         struct nvme_command c = { };
 181         int ret;
 182
 183         c.common.opcode = nvme_cmd_resv_report;
 184         c.common.cdw10 = cpu_to_le32(nvme_bytes_to_numd(data_len));
 185         c.common.cdw11 = cpu_to_le32(NVME_EXTENDED_DATA_STRUCT);
 186         *eds = true;
 187
 188 retry:
 189         ret = nvme_send_pr_command(bdev, &c, data, data_len);
 190         if (ret == NVME_SC_HOST_ID_INCONSIST &&
 191             c.common.cdw11 == cpu_to_le32(NVME_EXTENDED_DATA_STRUCT)) {
 192                 c.common.cdw11 = 0;
 193                 *eds = false;
 194                 goto retry;
 195         }
 196
 197         if (ret < 0)
 198                 return ret;
 199
 200         return nvme_sc_to_pr_err(ret);
 201 }
 202
 203 static int nvme_pr_read_keys(struct block_device *bdev,
 204                 struct pr_keys *keys_info)
 205 {
 206         u32 rse_len, num_keys = keys_info->num_keys;
 207         struct nvme_reservation_status_ext *rse;
 208         int ret, i;
 209         bool eds;
 210
 211         /*
 212          * Assume we are using 128-bit host IDs and allocate a buffer large
 213          * enough to get enough keys to fill the return keys buffer.
 214          */
 215         rse_len = struct_size(rse, regctl_eds, num_keys);
 216         rse = kzalloc(rse_len, GFP_KERNEL);
 217         if (!rse)
 218                 return -ENOMEM;
 219
 220         ret = nvme_pr_resv_report(bdev, rse, rse_len, &eds);
 221         if (ret)
 222                 goto free_rse;
 223
 224         keys_info->generation = le32_to_cpu(rse->gen);
 225         keys_info->num_keys = get_unaligned_le16(&rse->regctl);
 226
 227         num_keys = min(num_keys, keys_info->num_keys);
 228         for (i = 0; i < num_keys; i++) {
 229                 if (eds) {
 230                         keys_info->keys[i] =
 231                                         le64_to_cpu(rse->regctl_eds[i].rkey);
 232                 } else {
 233                         struct nvme_reservation_status *rs;
 234
 235                         rs = (struct nvme_reservation_status *)rse;
 236                         keys_info->keys[i] = le64_to_cpu(rs->regctl_ds[i].rkey);
 237                 }
 238         }
 239
 240 free_rse:
 241         kfree(rse);
 242         return ret;
 243 }
 244
 245 static int nvme_pr_read_reservation(struct block_device *bdev,
 246                 struct pr_held_reservation *resv)
 247 {
 248         struct nvme_reservation_status_ext tmp_rse, *rse;
 249         int ret, i, num_regs;
 250         u32 rse_len;
 251         bool eds;
 252
 253 get_num_regs:
 254         /*
 255          * Get the number of registrations so we know how big to allocate
 256          * the response buffer.
 257          */
 258         ret = nvme_pr_resv_report(bdev, &tmp_rse, sizeof(tmp_rse), &eds);
 259         if (ret)
 260                 return ret;
 261
 262         num_regs = get_unaligned_le16(&tmp_rse.regctl);
 263         if (!num_regs) {
 264                 resv->generation = le32_to_cpu(tmp_rse.gen);
 265                 return 0;
 266         }
 267
 268         rse_len = struct_size(rse, regctl_eds, num_regs);
 269         rse = kzalloc(rse_len, GFP_KERNEL);
 270         if (!rse)
 271                 return -ENOMEM;
 272
 273         ret = nvme_pr_resv_report(bdev, rse, rse_len, &eds);
 274         if (ret)
 275                 goto free_rse;
 276
 277         if (num_regs != get_unaligned_le16(&rse->regctl)) {
 278                 kfree(rse);
 279                 goto get_num_regs;
 280         }
 281
 282         resv->generation = le32_to_cpu(rse->gen);
 283         resv->type = block_pr_type_from_nvme(rse->rtype);
 284
 285         for (i = 0; i < num_regs; i++) {
 286                 if (eds) {
 287                         if (rse->regctl_eds[i].rcsts) {
 288                                 resv->key = le64_to_cpu(rse->regctl_eds[i].rkey);
 289                                 break;
 290                         }
 291                 } else {
 292                         struct nvme_reservation_status *rs;
 293
 294                         rs = (struct nvme_reservation_status *)rse;
 295                         if (rs->regctl_ds[i].rcsts) {
 296                                 resv->key = le64_to_cpu(rs->regctl_ds[i].rkey);
 297                                 break;
 298                         }
 299                 }
 300         }
 301
 302 free_rse:
 303         kfree(rse);
 304         return ret;
 305 }
 306
 307 const struct pr_ops nvme_pr_ops = {
 308         .pr_register    = nvme_pr_register,
 309         .pr_reserve     = nvme_pr_reserve,
 310         .pr_release     = nvme_pr_release,
 311         .pr_preempt     = nvme_pr_preempt,
 312         .pr_clear       = nvme_pr_clear,
 313         .pr_read_keys   = nvme_pr_read_keys,
 314         .pr_read_reservation = nvme_pr_read_reservation,
 315 };