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_simple_remove(&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         nd_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         nd_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         nd_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         nd_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         nd_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         nd_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         nd_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         nd_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 device *__nd_btt_create(struct nd_region *nd_region,
 182                                       unsigned long lbasize, uuid_t *uuid,
 183                                       struct nd_namespace_common *ndns)
 184 {
 185         struct nd_btt *nd_btt;
 186         struct device *dev;
 187
 188         nd_btt = kzalloc(sizeof(*nd_btt), GFP_KERNEL);
 189         if (!nd_btt)
 190                 return NULL;
 191
 192         nd_btt->id = ida_simple_get(&nd_region->btt_ida, 0, 0, GFP_KERNEL);
 193         if (nd_btt->id < 0)
 194                 goto out_nd_btt;
 195
 196         nd_btt->lbasize = lbasize;
 197         if (uuid) {
 198                 uuid = kmemdup(uuid, 16, GFP_KERNEL);
 199                 if (!uuid)
 200                         goto out_put_id;
 201         }
 202         nd_btt->uuid = uuid;
 203         dev = &nd_btt->dev;
 204         dev_set_name(dev, "btt%d.%d", nd_region->id, nd_btt->id);
 205         dev->parent = &nd_region->dev;
 206         dev->type = &nd_btt_device_type;
 207         device_initialize(&nd_btt->dev);
 208         if (ndns && !__nd_attach_ndns(&nd_btt->dev, ndns, &nd_btt->ndns)) {
 209                 dev_dbg(&ndns->dev, "failed, already claimed by %s\n",
 210                                 dev_name(ndns->claim));
 211                 put_device(dev);
 212                 return NULL;
 213         }
 214         return dev;
 215
 216 out_put_id:
 217         ida_simple_remove(&nd_region->btt_ida, nd_btt->id);
 218
 219 out_nd_btt:
 220         kfree(nd_btt);
 221         return NULL;
 222 }
 223
 224 struct device *nd_btt_create(struct nd_region *nd_region)
 225 {
 226         struct device *dev = __nd_btt_create(nd_region, 0, NULL, NULL);
 227
 228         __nd_device_register(dev);
 229         return dev;
 230 }
 231
 232 /**
 233  * nd_btt_arena_is_valid - check if the metadata layout is valid
 234  * @nd_btt:     device with BTT geometry and backing device info
 235  * @super:      pointer to the arena's info block being tested
 236  *
 237  * Check consistency of the btt info block with itself by validating
 238  * the checksum, and with the parent namespace by verifying the
 239  * parent_uuid contained in the info block with the one supplied in.
 240  *
 241  * Returns:
 242  * false for an invalid info block, true for a valid one
 243  */
 244 bool nd_btt_arena_is_valid(struct nd_btt *nd_btt, struct btt_sb *super)
 245 {
 246         const uuid_t *ns_uuid = nd_dev_to_uuid(&nd_btt->ndns->dev);
 247         uuid_t parent_uuid;
 248         u64 checksum;
 249
 250         if (memcmp(super->signature, BTT_SIG, BTT_SIG_LEN) != 0)
 251                 return false;
 252
 253         import_uuid(&parent_uuid, super->parent_uuid);
 254         if (!uuid_is_null(&parent_uuid))
 255                 if (!uuid_equal(&parent_uuid, ns_uuid))
 256                         return false;
 257
 258         checksum = le64_to_cpu(super->checksum);
 259         super->checksum = 0;
 260         if (checksum != nd_sb_checksum((struct nd_gen_sb *) super))
 261                 return false;
 262         super->checksum = cpu_to_le64(checksum);
 263
 264         /* TODO: figure out action for this */
 265         if ((le32_to_cpu(super->flags) & IB_FLAG_ERROR_MASK) != 0)
 266                 dev_info(&nd_btt->dev, "Found arena with an error flag\n");
 267
 268         return true;
 269 }
 270 EXPORT_SYMBOL(nd_btt_arena_is_valid);
 271
 272 int nd_btt_version(struct nd_btt *nd_btt, struct nd_namespace_common *ndns,
 273                 struct btt_sb *btt_sb)
 274 {
 275         if (ndns->claim_class == NVDIMM_CCLASS_BTT2) {
 276                 /* Probe/setup for BTT v2.0 */
 277                 nd_btt->initial_offset = 0;
 278                 nd_btt->version_major = 2;
 279                 nd_btt->version_minor = 0;
 280                 if (nvdimm_read_bytes(ndns, 0, btt_sb, sizeof(*btt_sb), 0))
 281                         return -ENXIO;
 282                 if (!nd_btt_arena_is_valid(nd_btt, btt_sb))
 283                         return -ENODEV;
 284                 if ((le16_to_cpu(btt_sb->version_major) != 2) ||
 285                                 (le16_to_cpu(btt_sb->version_minor) != 0))
 286                         return -ENODEV;
 287         } else {
 288                 /*
 289                  * Probe/setup for BTT v1.1 (NVDIMM_CCLASS_NONE or
 290                  * NVDIMM_CCLASS_BTT)
 291                  */
 292                 nd_btt->initial_offset = SZ_4K;
 293                 nd_btt->version_major = 1;
 294                 nd_btt->version_minor = 1;
 295                 if (nvdimm_read_bytes(ndns, SZ_4K, btt_sb, sizeof(*btt_sb), 0))
 296                         return -ENXIO;
 297                 if (!nd_btt_arena_is_valid(nd_btt, btt_sb))
 298                         return -ENODEV;
 299                 if ((le16_to_cpu(btt_sb->version_major) != 1) ||
 300                                 (le16_to_cpu(btt_sb->version_minor) != 1))
 301                         return -ENODEV;
 302         }
 303         return 0;
 304 }
 305 EXPORT_SYMBOL(nd_btt_version);
 306
 307 static int __nd_btt_probe(struct nd_btt *nd_btt,
 308                 struct nd_namespace_common *ndns, struct btt_sb *btt_sb)
 309 {
 310         int rc;
 311
 312         if (!btt_sb || !ndns || !nd_btt)
 313                 return -ENODEV;
 314
 315         if (nvdimm_namespace_capacity(ndns) < SZ_16M)
 316                 return -ENXIO;
 317
 318         rc = nd_btt_version(nd_btt, ndns, btt_sb);
 319         if (rc < 0)
 320                 return rc;
 321
 322         nd_btt->lbasize = le32_to_cpu(btt_sb->external_lbasize);
 323         nd_btt->uuid = kmemdup(&btt_sb->uuid, sizeof(uuid_t), GFP_KERNEL);
 324         if (!nd_btt->uuid)
 325                 return -ENOMEM;
 326
 327         __nd_device_register(&nd_btt->dev);
 328
 329         return 0;
 330 }
 331
 332 int nd_btt_probe(struct device *dev, struct nd_namespace_common *ndns)
 333 {
 334         int rc;
 335         struct device *btt_dev;
 336         struct btt_sb *btt_sb;
 337         struct nd_region *nd_region = to_nd_region(ndns->dev.parent);
 338
 339         if (ndns->force_raw)
 340                 return -ENODEV;
 341
 342         switch (ndns->claim_class) {
 343         case NVDIMM_CCLASS_NONE:
 344         case NVDIMM_CCLASS_BTT:
 345         case NVDIMM_CCLASS_BTT2:
 346                 break;
 347         default:
 348                 return -ENODEV;
 349         }
 350
 351         nvdimm_bus_lock(&ndns->dev);
 352         btt_dev = __nd_btt_create(nd_region, 0, NULL, ndns);
 353         nvdimm_bus_unlock(&ndns->dev);
 354         if (!btt_dev)
 355                 return -ENOMEM;
 356         btt_sb = devm_kzalloc(dev, sizeof(*btt_sb), GFP_KERNEL);
 357         rc = __nd_btt_probe(to_nd_btt(btt_dev), ndns, btt_sb);
 358         dev_dbg(dev, "btt: %s\n", rc == 0 ? dev_name(btt_dev) : "<none>");
 359         if (rc < 0) {
 360                 struct nd_btt *nd_btt = to_nd_btt(btt_dev);
 361
 362                 nd_detach_ndns(btt_dev, &nd_btt->ndns);
 363                 put_device(btt_dev);
 364         }
 365
 366         return rc;
 367 }
 368 EXPORT_SYMBOL(nd_btt_probe);