drivers/nvdimm/btt_devs.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright(c) 2013-2015 Intel Corporation. All rights reserved.
   4  */
   5 #include <linux/blkdev.h>
   6 #include <linux/device.h>
   7 #include <linux/sizes.h>
   8 #include <linux/slab.h>
   9 #include <linux/fs.h>
  10 #include <linux/mm.h>
  11 #include "nd-core.h"
  12 #include "btt.h"
  13 #include "nd.h"
  14
  15 static void nd_btt_release(struct device *dev)
  16 {
  17         struct nd_region *nd_region = to_nd_region(dev->parent);
  18         struct nd_btt *nd_btt = to_nd_btt(dev);
  19
  20         dev_dbg(dev, "trace\n");
  21         nd_detach_ndns(&nd_btt->dev, &nd_btt->ndns);
  22         ida_free(&nd_region->btt_ida, nd_btt->id);
  23         kfree(nd_btt->uuid);
  24         kfree(nd_btt);
  25 }
  26
  27 struct nd_btt *to_nd_btt(struct device *dev)
  28 {
  29         struct nd_btt *nd_btt = container_of(dev, struct nd_btt, dev);
  30
  31         WARN_ON(!is_nd_btt(dev));
  32         return nd_btt;
  33 }
  34 EXPORT_SYMBOL(to_nd_btt);
  35
  36 static const unsigned long btt_lbasize_supported[] = { 512, 520, 528,
  37         4096, 4104, 4160, 4224, 0 };
  38
  39 static ssize_t sector_size_show(struct device *dev,
  40                 struct device_attribute *attr, char *buf)
  41 {
  42         struct nd_btt *nd_btt = to_nd_btt(dev);
  43
  44         return nd_size_select_show(nd_btt->lbasize, btt_lbasize_supported, buf);
  45 }
  46
  47 static ssize_t sector_size_store(struct device *dev,
  48                 struct device_attribute *attr, const char *buf, size_t len)
  49 {
  50         struct nd_btt *nd_btt = to_nd_btt(dev);
  51         ssize_t rc;
  52
  53         device_lock(dev);
  54         nvdimm_bus_lock(dev);
  55         rc = nd_size_select_store(dev, buf, &nd_btt->lbasize,
  56                         btt_lbasize_supported);
  57         dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf,
  58                         buf[len - 1] == '\n' ? "" : "\n");
  59         nvdimm_bus_unlock(dev);
  60         device_unlock(dev);
  61
  62         return rc ? rc : len;
  63 }
  64 static DEVICE_ATTR_RW(sector_size);
  65
  66 static ssize_t uuid_show(struct device *dev,
  67                 struct device_attribute *attr, char *buf)
  68 {
  69         struct nd_btt *nd_btt = to_nd_btt(dev);
  70
  71         if (nd_btt->uuid)
  72                 return sprintf(buf, "%pUb\n", nd_btt->uuid);
  73         return sprintf(buf, "\n");
  74 }
  75
  76 static ssize_t uuid_store(struct device *dev,
  77                 struct device_attribute *attr, const char *buf, size_t len)
  78 {
  79         struct nd_btt *nd_btt = to_nd_btt(dev);
  80         ssize_t rc;
  81
  82         device_lock(dev);
  83         rc = nd_uuid_store(dev, &nd_btt->uuid, buf, len);
  84         dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf,
  85                         buf[len - 1] == '\n' ? "" : "\n");
  86         device_unlock(dev);
  87
  88         return rc ? rc : len;
  89 }
  90 static DEVICE_ATTR_RW(uuid);
  91
  92 static ssize_t namespace_show(struct device *dev,
  93                 struct device_attribute *attr, char *buf)
  94 {
  95         struct nd_btt *nd_btt = to_nd_btt(dev);
  96         ssize_t rc;
  97
  98         nvdimm_bus_lock(dev);
  99         rc = sprintf(buf, "%s\n", nd_btt->ndns
 100                         ? dev_name(&nd_btt->ndns->dev) : "");
 101         nvdimm_bus_unlock(dev);
 102         return rc;
 103 }
 104
 105 static ssize_t namespace_store(struct device *dev,
 106                 struct device_attribute *attr, const char *buf, size_t len)
 107 {
 108         struct nd_btt *nd_btt = to_nd_btt(dev);
 109         ssize_t rc;
 110
 111         device_lock(dev);
 112         nvdimm_bus_lock(dev);
 113         rc = nd_namespace_store(dev, &nd_btt->ndns, buf, len);
 114         dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf,
 115                         buf[len - 1] == '\n' ? "" : "\n");
 116         nvdimm_bus_unlock(dev);
 117         device_unlock(dev);
 118
 119         return rc;
 120 }
 121 static DEVICE_ATTR_RW(namespace);
 122
 123 static ssize_t size_show(struct device *dev,
 124                 struct device_attribute *attr, char *buf)
 125 {
 126         struct nd_btt *nd_btt = to_nd_btt(dev);
 127         ssize_t rc;
 128
 129         device_lock(dev);
 130         if (dev->driver)
 131                 rc = sprintf(buf, "%llu\n", nd_btt->size);
 132         else {
 133                 /* no size to convey if the btt instance is disabled */
 134                 rc = -ENXIO;
 135         }
 136         device_unlock(dev);
 137
 138         return rc;
 139 }
 140 static DEVICE_ATTR_RO(size);
 141
 142 static ssize_t log_zero_flags_show(struct device *dev,
 143                 struct device_attribute *attr, char *buf)
 144 {
 145         return sprintf(buf, "Y\n");
 146 }
 147 static DEVICE_ATTR_RO(log_zero_flags);
 148
 149 static struct attribute *nd_btt_attributes[] = {
 150         &dev_attr_sector_size.attr,
 151         &dev_attr_namespace.attr,
 152         &dev_attr_uuid.attr,
 153         &dev_attr_size.attr,
 154         &dev_attr_log_zero_flags.attr,
 155         NULL,
 156 };
 157
 158 static struct attribute_group nd_btt_attribute_group = {
 159         .attrs = nd_btt_attributes,
 160 };
 161
 162 static const struct attribute_group *nd_btt_attribute_groups[] = {
 163         &nd_btt_attribute_group,
 164         &nd_device_attribute_group,
 165         &nd_numa_attribute_group,
 166         NULL,
 167 };
 168
 169 static const struct device_type nd_btt_device_type = {
 170         .name = "nd_btt",
 171         .release = nd_btt_release,
 172         .groups = nd_btt_attribute_groups,
 173 };
 174
 175 bool is_nd_btt(struct device *dev)
 176 {
 177         return dev->type == &nd_btt_device_type;
 178 }
 179 EXPORT_SYMBOL(is_nd_btt);
 180
 181 static struct lock_class_key nvdimm_btt_key;
 182
 183 static struct device *__nd_btt_create(struct nd_region *nd_region,
 184                                       unsigned long lbasize, uuid_t *uuid,
 185                                       struct nd_namespace_common *ndns)
 186 {
 187         struct nd_btt *nd_btt;
 188         struct device *dev;
 189
 190         nd_btt = kzalloc(sizeof(*nd_btt), GFP_KERNEL);
 191         if (!nd_btt)
 192                 return NULL;
 193
 194         nd_btt->id = ida_alloc(&nd_region->btt_ida, GFP_KERNEL);
 195         if (nd_btt->id < 0)
 196                 goto out_nd_btt;
 197
 198         nd_btt->lbasize = lbasize;
 199         if (uuid) {
 200                 uuid = kmemdup(uuid, 16, GFP_KERNEL);
 201                 if (!uuid)
 202                         goto out_put_id;
 203         }
 204         nd_btt->uuid = uuid;
 205         dev = &nd_btt->dev;
 206         dev_set_name(dev, "btt%d.%d", nd_region->id, nd_btt->id);
 207         dev->parent = &nd_region->dev;
 208         dev->type = &nd_btt_device_type;
 209         device_initialize(&nd_btt->dev);
 210         lockdep_set_class(&nd_btt->dev.mutex, &nvdimm_btt_key);
 211         if (ndns && !__nd_attach_ndns(&nd_btt->dev, ndns, &nd_btt->ndns)) {
 212                 dev_dbg(&ndns->dev, "failed, already claimed by %s\n",
 213                                 dev_name(ndns->claim));
 214                 put_device(dev);
 215                 return NULL;
 216         }
 217         return dev;
 218
 219 out_put_id:
 220         ida_free(&nd_region->btt_ida, nd_btt->id);
 221
 222 out_nd_btt:
 223         kfree(nd_btt);
 224         return NULL;
 225 }
 226
 227 struct device *nd_btt_create(struct nd_region *nd_region)
 228 {
 229         struct device *dev = __nd_btt_create(nd_region, 0, NULL, NULL);
 230
 231         nd_device_register(dev);
 232         return dev;
 233 }
 234
 235 /**
 236  * nd_btt_arena_is_valid - check if the metadata layout is valid
 237  * @nd_btt:     device with BTT geometry and backing device info
 238  * @super:      pointer to the arena's info block being tested
 239  *
 240  * Check consistency of the btt info block with itself by validating
 241  * the checksum, and with the parent namespace by verifying the
 242  * parent_uuid contained in the info block with the one supplied in.
 243  *
 244  * Returns:
 245  * false for an invalid info block, true for a valid one
 246  */
 247 bool nd_btt_arena_is_valid(struct nd_btt *nd_btt, struct btt_sb *super)
 248 {
 249         const uuid_t *ns_uuid = nd_dev_to_uuid(&nd_btt->ndns->dev);
 250         uuid_t parent_uuid;
 251         u64 checksum;
 252
 253         if (memcmp(super->signature, BTT_SIG, BTT_SIG_LEN) != 0)
 254                 return false;
 255
 256         import_uuid(&parent_uuid, super->parent_uuid);
 257         if (!uuid_is_null(&parent_uuid))
 258                 if (!uuid_equal(&parent_uuid, ns_uuid))
 259                         return false;
 260
 261         checksum = le64_to_cpu(super->checksum);
 262         super->checksum = 0;
 263         if (checksum != nd_sb_checksum((struct nd_gen_sb *) super))
 264                 return false;
 265         super->checksum = cpu_to_le64(checksum);
 266
 267         /* TODO: figure out action for this */
 268         if ((le32_to_cpu(super->flags) & IB_FLAG_ERROR_MASK) != 0)
 269                 dev_info(&nd_btt->dev, "Found arena with an error flag\n");
 270
 271         return true;
 272 }
 273 EXPORT_SYMBOL(nd_btt_arena_is_valid);
 274
 275 int nd_btt_version(struct nd_btt *nd_btt, struct nd_namespace_common *ndns,
 276                 struct btt_sb *btt_sb)
 277 {
 278         if (ndns->claim_class == NVDIMM_CCLASS_BTT2) {
 279                 /* Probe/setup for BTT v2.0 */
 280                 nd_btt->initial_offset = 0;
 281                 nd_btt->version_major = 2;
 282                 nd_btt->version_minor = 0;
 283                 if (nvdimm_read_bytes(ndns, 0, btt_sb, sizeof(*btt_sb), 0))
 284                         return -ENXIO;
 285                 if (!nd_btt_arena_is_valid(nd_btt, btt_sb))
 286                         return -ENODEV;
 287                 if ((le16_to_cpu(btt_sb->version_major) != 2) ||
 288                                 (le16_to_cpu(btt_sb->version_minor) != 0))
 289                         return -ENODEV;
 290         } else {
 291                 /*
 292                  * Probe/setup for BTT v1.1 (NVDIMM_CCLASS_NONE or
 293                  * NVDIMM_CCLASS_BTT)
 294                  */
 295                 nd_btt->initial_offset = SZ_4K;
 296                 nd_btt->version_major = 1;
 297                 nd_btt->version_minor = 1;
 298                 if (nvdimm_read_bytes(ndns, SZ_4K, btt_sb, sizeof(*btt_sb), 0))
 299                         return -ENXIO;
 300                 if (!nd_btt_arena_is_valid(nd_btt, btt_sb))
 301                         return -ENODEV;
 302                 if ((le16_to_cpu(btt_sb->version_major) != 1) ||
 303                                 (le16_to_cpu(btt_sb->version_minor) != 1))
 304                         return -ENODEV;
 305         }
 306         return 0;
 307 }
 308 EXPORT_SYMBOL(nd_btt_version);
 309
 310 static int __nd_btt_probe(struct nd_btt *nd_btt,
 311                 struct nd_namespace_common *ndns, struct btt_sb *btt_sb)
 312 {
 313         int rc;
 314
 315         if (!btt_sb || !ndns || !nd_btt)
 316                 return -ENODEV;
 317
 318         if (nvdimm_namespace_capacity(ndns) < SZ_16M)
 319                 return -ENXIO;
 320
 321         rc = nd_btt_version(nd_btt, ndns, btt_sb);
 322         if (rc < 0)
 323                 return rc;
 324
 325         nd_btt->lbasize = le32_to_cpu(btt_sb->external_lbasize);
 326         nd_btt->uuid = kmemdup(&btt_sb->uuid, sizeof(uuid_t), GFP_KERNEL);
 327         if (!nd_btt->uuid)
 328                 return -ENOMEM;
 329
 330         nd_device_register(&nd_btt->dev);
 331
 332         return 0;
 333 }
 334
 335 int nd_btt_probe(struct device *dev, struct nd_namespace_common *ndns)
 336 {
 337         int rc;
 338         struct device *btt_dev;
 339         struct btt_sb *btt_sb;
 340         struct nd_region *nd_region = to_nd_region(ndns->dev.parent);
 341
 342         if (ndns->force_raw)
 343                 return -ENODEV;
 344
 345         switch (ndns->claim_class) {
 346         case NVDIMM_CCLASS_NONE:
 347         case NVDIMM_CCLASS_BTT:
 348         case NVDIMM_CCLASS_BTT2:
 349                 break;
 350         default:
 351                 return -ENODEV;
 352         }
 353
 354         nvdimm_bus_lock(&ndns->dev);
 355         btt_dev = __nd_btt_create(nd_region, 0, NULL, ndns);
 356         nvdimm_bus_unlock(&ndns->dev);
 357         if (!btt_dev)
 358                 return -ENOMEM;
 359         btt_sb = devm_kzalloc(dev, sizeof(*btt_sb), GFP_KERNEL);
 360         rc = __nd_btt_probe(to_nd_btt(btt_dev), ndns, btt_sb);
 361         dev_dbg(dev, "btt: %s\n", rc == 0 ? dev_name(btt_dev) : "<none>");
 362         if (rc < 0) {
 363                 struct nd_btt *nd_btt = to_nd_btt(btt_dev);
 364
 365                 nd_detach_ndns(btt_dev, &nd_btt->ndns);
 366                 put_device(btt_dev);
 367         }
 368
 369         return rc;
 370 }
 371 EXPORT_SYMBOL(nd_btt_probe);