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/genhd.h>
   8 #include <linux/sizes.h>
   9 #include <linux/slab.h>
  10 #include <linux/fs.h>
  11 #include <linux/mm.h>
  12 #include "nd-core.h"
  13 #include "btt.h"
  14 #include "nd.h"
  15
  16 static void nd_btt_release(struct device *dev)
  17 {
  18         struct nd_region *nd_region = to_nd_region(dev->parent);
  19         struct nd_btt *nd_btt = to_nd_btt(dev);
  20
  21         dev_dbg(dev, "trace\n");
  22         nd_detach_ndns(&nd_btt->dev, &nd_btt->ndns);
  23         ida_simple_remove(&nd_region->btt_ida, nd_btt->id);
  24         kfree(nd_btt->uuid);
  25         kfree(nd_btt);
  26 }
  27
  28 static struct device_type nd_btt_device_type = {
  29         .name = "nd_btt",
  30         .release = nd_btt_release,
  31 };
  32
  33 bool is_nd_btt(struct device *dev)
  34 {
  35         return dev->type == &nd_btt_device_type;
  36 }
  37 EXPORT_SYMBOL(is_nd_btt);
  38
  39 struct nd_btt *to_nd_btt(struct device *dev)
  40 {
  41         struct nd_btt *nd_btt = container_of(dev, struct nd_btt, dev);
  42
  43         WARN_ON(!is_nd_btt(dev));
  44         return nd_btt;
  45 }
  46 EXPORT_SYMBOL(to_nd_btt);
  47
  48 static const unsigned long btt_lbasize_supported[] = { 512, 520, 528,
  49         4096, 4104, 4160, 4224, 0 };
  50
  51 static ssize_t sector_size_show(struct device *dev,
  52                 struct device_attribute *attr, char *buf)
  53 {
  54         struct nd_btt *nd_btt = to_nd_btt(dev);
  55
  56         return nd_size_select_show(nd_btt->lbasize, btt_lbasize_supported, buf);
  57 }
  58
  59 static ssize_t sector_size_store(struct device *dev,
  60                 struct device_attribute *attr, const char *buf, size_t len)
  61 {
  62         struct nd_btt *nd_btt = to_nd_btt(dev);
  63         ssize_t rc;
  64
  65         nd_device_lock(dev);
  66         nvdimm_bus_lock(dev);
  67         rc = nd_size_select_store(dev, buf, &nd_btt->lbasize,
  68                         btt_lbasize_supported);
  69         dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf,
  70                         buf[len - 1] == '\n' ? "" : "\n");
  71         nvdimm_bus_unlock(dev);
  72         nd_device_unlock(dev);
  73
  74         return rc ? rc : len;
  75 }
  76 static DEVICE_ATTR_RW(sector_size);
  77
  78 static ssize_t uuid_show(struct device *dev,
  79                 struct device_attribute *attr, char *buf)
  80 {
  81         struct nd_btt *nd_btt = to_nd_btt(dev);
  82
  83         if (nd_btt->uuid)
  84                 return sprintf(buf, "%pUb\n", nd_btt->uuid);
  85         return sprintf(buf, "\n");
  86 }
  87
  88 static ssize_t uuid_store(struct device *dev,
  89                 struct device_attribute *attr, const char *buf, size_t len)
  90 {
  91         struct nd_btt *nd_btt = to_nd_btt(dev);
  92         ssize_t rc;
  93
  94         nd_device_lock(dev);
  95         rc = nd_uuid_store(dev, &nd_btt->uuid, buf, len);
  96         dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf,
  97                         buf[len - 1] == '\n' ? "" : "\n");
  98         nd_device_unlock(dev);
  99
 100         return rc ? rc : len;
 101 }
 102 static DEVICE_ATTR_RW(uuid);
 103
 104 static ssize_t namespace_show(struct device *dev,
 105                 struct device_attribute *attr, char *buf)
 106 {
 107         struct nd_btt *nd_btt = to_nd_btt(dev);
 108         ssize_t rc;
 109
 110         nvdimm_bus_lock(dev);
 111         rc = sprintf(buf, "%s\n", nd_btt->ndns
 112                         ? dev_name(&nd_btt->ndns->dev) : "");
 113         nvdimm_bus_unlock(dev);
 114         return rc;
 115 }
 116
 117 static ssize_t namespace_store(struct device *dev,
 118                 struct device_attribute *attr, const char *buf, size_t len)
 119 {
 120         struct nd_btt *nd_btt = to_nd_btt(dev);
 121         ssize_t rc;
 122
 123         nd_device_lock(dev);
 124         nvdimm_bus_lock(dev);
 125         rc = nd_namespace_store(dev, &nd_btt->ndns, buf, len);
 126         dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf,
 127                         buf[len - 1] == '\n' ? "" : "\n");
 128         nvdimm_bus_unlock(dev);
 129         nd_device_unlock(dev);
 130
 131         return rc;
 132 }
 133 static DEVICE_ATTR_RW(namespace);
 134
 135 static ssize_t size_show(struct device *dev,
 136                 struct device_attribute *attr, char *buf)
 137 {
 138         struct nd_btt *nd_btt = to_nd_btt(dev);
 139         ssize_t rc;
 140
 141         nd_device_lock(dev);
 142         if (dev->driver)
 143                 rc = sprintf(buf, "%llu\n", nd_btt->size);
 144         else {
 145                 /* no size to convey if the btt instance is disabled */
 146                 rc = -ENXIO;
 147         }
 148         nd_device_unlock(dev);
 149
 150         return rc;
 151 }
 152 static DEVICE_ATTR_RO(size);
 153
 154 static ssize_t log_zero_flags_show(struct device *dev,
 155                 struct device_attribute *attr, char *buf)
 156 {
 157         return sprintf(buf, "Y\n");
 158 }
 159 static DEVICE_ATTR_RO(log_zero_flags);
 160
 161 static struct attribute *nd_btt_attributes[] = {
 162         &dev_attr_sector_size.attr,
 163         &dev_attr_namespace.attr,
 164         &dev_attr_uuid.attr,
 165         &dev_attr_size.attr,
 166         &dev_attr_log_zero_flags.attr,
 167         NULL,
 168 };
 169
 170 static struct attribute_group nd_btt_attribute_group = {
 171         .attrs = nd_btt_attributes,
 172 };
 173
 174 static const struct attribute_group *nd_btt_attribute_groups[] = {
 175         &nd_btt_attribute_group,
 176         &nd_device_attribute_group,
 177         &nd_numa_attribute_group,
 178         NULL,
 179 };
 180
 181 static struct device *__nd_btt_create(struct nd_region *nd_region,
 182                 unsigned long lbasize, u8 *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         dev->groups = nd_btt_attribute_groups;
 208         device_initialize(&nd_btt->dev);
 209         if (ndns && !__nd_attach_ndns(&nd_btt->dev, ndns, &nd_btt->ndns)) {
 210                 dev_dbg(&ndns->dev, "failed, already claimed by %s\n",
 211                                 dev_name(ndns->claim));
 212                 put_device(dev);
 213                 return NULL;
 214         }
 215         return dev;
 216
 217 out_put_id:
 218         ida_simple_remove(&nd_region->btt_ida, nd_btt->id);
 219
 220 out_nd_btt:
 221         kfree(nd_btt);
 222         return NULL;
 223 }
 224
 225 struct device *nd_btt_create(struct nd_region *nd_region)
 226 {
 227         struct device *dev = __nd_btt_create(nd_region, 0, NULL, NULL);
 228
 229         __nd_device_register(dev);
 230         return dev;
 231 }
 232
 233 /**
 234  * nd_btt_arena_is_valid - check if the metadata layout is valid
 235  * @nd_btt:     device with BTT geometry and backing device info
 236  * @super:      pointer to the arena's info block being tested
 237  *
 238  * Check consistency of the btt info block with itself by validating
 239  * the checksum, and with the parent namespace by verifying the
 240  * parent_uuid contained in the info block with the one supplied in.
 241  *
 242  * Returns:
 243  * false for an invalid info block, true for a valid one
 244  */
 245 bool nd_btt_arena_is_valid(struct nd_btt *nd_btt, struct btt_sb *super)
 246 {
 247         const u8 *parent_uuid = nd_dev_to_uuid(&nd_btt->ndns->dev);
 248         u64 checksum;
 249
 250         if (memcmp(super->signature, BTT_SIG, BTT_SIG_LEN) != 0)
 251                 return false;
 252
 253         if (!guid_is_null((guid_t *)&super->parent_uuid))
 254                 if (memcmp(super->parent_uuid, parent_uuid, 16) != 0)
 255                         return false;
 256
 257         checksum = le64_to_cpu(super->checksum);
 258         super->checksum = 0;
 259         if (checksum != nd_sb_checksum((struct nd_gen_sb *) super))
 260                 return false;
 261         super->checksum = cpu_to_le64(checksum);
 262
 263         /* TODO: figure out action for this */
 264         if ((le32_to_cpu(super->flags) & IB_FLAG_ERROR_MASK) != 0)
 265                 dev_info(&nd_btt->dev, "Found arena with an error flag\n");
 266
 267         return true;
 268 }
 269 EXPORT_SYMBOL(nd_btt_arena_is_valid);
 270
 271 int nd_btt_version(struct nd_btt *nd_btt, struct nd_namespace_common *ndns,
 272                 struct btt_sb *btt_sb)
 273 {
 274         if (ndns->claim_class == NVDIMM_CCLASS_BTT2) {
 275                 /* Probe/setup for BTT v2.0 */
 276                 nd_btt->initial_offset = 0;
 277                 nd_btt->version_major = 2;
 278                 nd_btt->version_minor = 0;
 279                 if (nvdimm_read_bytes(ndns, 0, btt_sb, sizeof(*btt_sb), 0))
 280                         return -ENXIO;
 281                 if (!nd_btt_arena_is_valid(nd_btt, btt_sb))
 282                         return -ENODEV;
 283                 if ((le16_to_cpu(btt_sb->version_major) != 2) ||
 284                                 (le16_to_cpu(btt_sb->version_minor) != 0))
 285                         return -ENODEV;
 286         } else {
 287                 /*
 288                  * Probe/setup for BTT v1.1 (NVDIMM_CCLASS_NONE or
 289                  * NVDIMM_CCLASS_BTT)
 290                  */
 291                 nd_btt->initial_offset = SZ_4K;
 292                 nd_btt->version_major = 1;
 293                 nd_btt->version_minor = 1;
 294                 if (nvdimm_read_bytes(ndns, SZ_4K, btt_sb, sizeof(*btt_sb), 0))
 295                         return -ENXIO;
 296                 if (!nd_btt_arena_is_valid(nd_btt, btt_sb))
 297                         return -ENODEV;
 298                 if ((le16_to_cpu(btt_sb->version_major) != 1) ||
 299                                 (le16_to_cpu(btt_sb->version_minor) != 1))
 300                         return -ENODEV;
 301         }
 302         return 0;
 303 }
 304 EXPORT_SYMBOL(nd_btt_version);
 305
 306 static int __nd_btt_probe(struct nd_btt *nd_btt,
 307                 struct nd_namespace_common *ndns, struct btt_sb *btt_sb)
 308 {
 309         int rc;
 310
 311         if (!btt_sb || !ndns || !nd_btt)
 312                 return -ENODEV;
 313
 314         if (nvdimm_namespace_capacity(ndns) < SZ_16M)
 315                 return -ENXIO;
 316
 317         rc = nd_btt_version(nd_btt, ndns, btt_sb);
 318         if (rc < 0)
 319                 return rc;
 320
 321         nd_btt->lbasize = le32_to_cpu(btt_sb->external_lbasize);
 322         nd_btt->uuid = kmemdup(btt_sb->uuid, 16, GFP_KERNEL);
 323         if (!nd_btt->uuid)
 324                 return -ENOMEM;
 325
 326         __nd_device_register(&nd_btt->dev);
 327
 328         return 0;
 329 }
 330
 331 int nd_btt_probe(struct device *dev, struct nd_namespace_common *ndns)
 332 {
 333         int rc;
 334         struct device *btt_dev;
 335         struct btt_sb *btt_sb;
 336         struct nd_region *nd_region = to_nd_region(ndns->dev.parent);
 337
 338         if (ndns->force_raw)
 339                 return -ENODEV;
 340
 341         switch (ndns->claim_class) {
 342         case NVDIMM_CCLASS_NONE:
 343         case NVDIMM_CCLASS_BTT:
 344         case NVDIMM_CCLASS_BTT2:
 345                 break;
 346         default:
 347                 return -ENODEV;
 348         }
 349
 350         nvdimm_bus_lock(&ndns->dev);
 351         btt_dev = __nd_btt_create(nd_region, 0, NULL, ndns);
 352         nvdimm_bus_unlock(&ndns->dev);
 353         if (!btt_dev)
 354                 return -ENOMEM;
 355         btt_sb = devm_kzalloc(dev, sizeof(*btt_sb), GFP_KERNEL);
 356         rc = __nd_btt_probe(to_nd_btt(btt_dev), ndns, btt_sb);
 357         dev_dbg(dev, "btt: %s\n", rc == 0 ? dev_name(btt_dev) : "<none>");
 358         if (rc < 0) {
 359                 struct nd_btt *nd_btt = to_nd_btt(btt_dev);
 360
 361                 nd_detach_ndns(btt_dev, &nd_btt->ndns);
 362                 put_device(btt_dev);
 363         }
 364
 365         return rc;
 366 }
 367 EXPORT_SYMBOL(nd_btt_probe);