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 struct nd_btt *to_nd_btt(struct device *dev)
  29 {
  30         struct nd_btt *nd_btt = container_of(dev, struct nd_btt, dev);
  31
  32         WARN_ON(!is_nd_btt(dev));
  33         return nd_btt;
  34 }
  35 EXPORT_SYMBOL(to_nd_btt);
  36
  37 static const unsigned long btt_lbasize_supported[] = { 512, 520, 528,
  38         4096, 4104, 4160, 4224, 0 };
  39
  40 static ssize_t sector_size_show(struct device *dev,
  41                 struct device_attribute *attr, char *buf)
  42 {
  43         struct nd_btt *nd_btt = to_nd_btt(dev);
  44
  45         return nd_size_select_show(nd_btt->lbasize, btt_lbasize_supported, buf);
  46 }
  47
  48 static ssize_t sector_size_store(struct device *dev,
  49                 struct device_attribute *attr, const char *buf, size_t len)
  50 {
  51         struct nd_btt *nd_btt = to_nd_btt(dev);
  52         ssize_t rc;
  53
  54         nd_device_lock(dev);
  55         nvdimm_bus_lock(dev);
  56         rc = nd_size_select_store(dev, buf, &nd_btt->lbasize,
  57                         btt_lbasize_supported);
  58         dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf,
  59                         buf[len - 1] == '\n' ? "" : "\n");
  60         nvdimm_bus_unlock(dev);
  61         nd_device_unlock(dev);
  62
  63         return rc ? rc : len;
  64 }
  65 static DEVICE_ATTR_RW(sector_size);
  66
  67 static ssize_t uuid_show(struct device *dev,
  68                 struct device_attribute *attr, char *buf)
  69 {
  70         struct nd_btt *nd_btt = to_nd_btt(dev);
  71
  72         if (nd_btt->uuid)
  73                 return sprintf(buf, "%pUb\n", nd_btt->uuid);
  74         return sprintf(buf, "\n");
  75 }
  76
  77 static ssize_t uuid_store(struct device *dev,
  78                 struct device_attribute *attr, const char *buf, size_t len)
  79 {
  80         struct nd_btt *nd_btt = to_nd_btt(dev);
  81         ssize_t rc;
  82
  83         nd_device_lock(dev);
  84         rc = nd_uuid_store(dev, &nd_btt->uuid, buf, len);
  85         dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf,
  86                         buf[len - 1] == '\n' ? "" : "\n");
  87         nd_device_unlock(dev);
  88
  89         return rc ? rc : len;
  90 }
  91 static DEVICE_ATTR_RW(uuid);
  92
  93 static ssize_t namespace_show(struct device *dev,
  94                 struct device_attribute *attr, char *buf)
  95 {
  96         struct nd_btt *nd_btt = to_nd_btt(dev);
  97         ssize_t rc;
  98
  99         nvdimm_bus_lock(dev);
 100         rc = sprintf(buf, "%s\n", nd_btt->ndns
 101                         ? dev_name(&nd_btt->ndns->dev) : "");
 102         nvdimm_bus_unlock(dev);
 103         return rc;
 104 }
 105
 106 static ssize_t namespace_store(struct device *dev,
 107                 struct device_attribute *attr, const char *buf, size_t len)
 108 {
 109         struct nd_btt *nd_btt = to_nd_btt(dev);
 110         ssize_t rc;
 111
 112         nd_device_lock(dev);
 113         nvdimm_bus_lock(dev);
 114         rc = nd_namespace_store(dev, &nd_btt->ndns, buf, len);
 115         dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf,
 116                         buf[len - 1] == '\n' ? "" : "\n");
 117         nvdimm_bus_unlock(dev);
 118         nd_device_unlock(dev);
 119
 120         return rc;
 121 }
 122 static DEVICE_ATTR_RW(namespace);
 123
 124 static ssize_t size_show(struct device *dev,
 125                 struct device_attribute *attr, char *buf)
 126 {
 127         struct nd_btt *nd_btt = to_nd_btt(dev);
 128         ssize_t rc;
 129
 130         nd_device_lock(dev);
 131         if (dev->driver)
 132                 rc = sprintf(buf, "%llu\n", nd_btt->size);
 133         else {
 134                 /* no size to convey if the btt instance is disabled */
 135                 rc = -ENXIO;
 136         }
 137         nd_device_unlock(dev);
 138
 139         return rc;
 140 }
 141 static DEVICE_ATTR_RO(size);
 142
 143 static ssize_t log_zero_flags_show(struct device *dev,
 144                 struct device_attribute *attr, char *buf)
 145 {
 146         return sprintf(buf, "Y\n");
 147 }
 148 static DEVICE_ATTR_RO(log_zero_flags);
 149
 150 static struct attribute *nd_btt_attributes[] = {
 151         &dev_attr_sector_size.attr,
 152         &dev_attr_namespace.attr,
 153         &dev_attr_uuid.attr,
 154         &dev_attr_size.attr,
 155         &dev_attr_log_zero_flags.attr,
 156         NULL,
 157 };
 158
 159 static struct attribute_group nd_btt_attribute_group = {
 160         .attrs = nd_btt_attributes,
 161 };
 162
 163 static const struct attribute_group *nd_btt_attribute_groups[] = {
 164         &nd_btt_attribute_group,
 165         &nd_device_attribute_group,
 166         &nd_numa_attribute_group,
 167         NULL,
 168 };
 169
 170 static const struct device_type nd_btt_device_type = {
 171         .name = "nd_btt",
 172         .release = nd_btt_release,
 173         .groups = nd_btt_attribute_groups,
 174 };
 175
 176 bool is_nd_btt(struct device *dev)
 177 {
 178         return dev->type == &nd_btt_device_type;
 179 }
 180 EXPORT_SYMBOL(is_nd_btt);
 181
 182 static struct device *__nd_btt_create(struct nd_region *nd_region,
 183                 unsigned long lbasize, u8 *uuid,
 184                 struct nd_namespace_common *ndns)
 185 {
 186         struct nd_btt *nd_btt;
 187         struct device *dev;
 188
 189         nd_btt = kzalloc(sizeof(*nd_btt), GFP_KERNEL);
 190         if (!nd_btt)
 191                 return NULL;
 192
 193         nd_btt->id = ida_simple_get(&nd_region->btt_ida, 0, 0, GFP_KERNEL);
 194         if (nd_btt->id < 0)
 195                 goto out_nd_btt;
 196
 197         nd_btt->lbasize = lbasize;
 198         if (uuid) {
 199                 uuid = kmemdup(uuid, 16, GFP_KERNEL);
 200                 if (!uuid)
 201                         goto out_put_id;
 202         }
 203         nd_btt->uuid = uuid;
 204         dev = &nd_btt->dev;
 205         dev_set_name(dev, "btt%d.%d", nd_region->id, nd_btt->id);
 206         dev->parent = &nd_region->dev;
 207         dev->type = &nd_btt_device_type;
 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);