drivers/nvdimm/core.c

   1 /*
   2  * Copyright(c) 2013-2015 Intel Corporation. All rights reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of version 2 of the GNU General Public License as
   6  * published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful, but
   9  * WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11  * General Public License for more details.
  12  */
  13 #include <linux/libnvdimm.h>
  14 #include <linux/export.h>
  15 #include <linux/module.h>
  16 #include <linux/blkdev.h>
  17 #include <linux/device.h>
  18 #include <linux/ctype.h>
  19 #include <linux/ndctl.h>
  20 #include <linux/mutex.h>
  21 #include <linux/slab.h>
  22 #include "nd-core.h"
  23 #include "nd.h"
  24
  25 LIST_HEAD(nvdimm_bus_list);
  26 DEFINE_MUTEX(nvdimm_bus_list_mutex);
  27 static DEFINE_IDA(nd_ida);
  28
  29 void nvdimm_bus_lock(struct device *dev)
  30 {
  31         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
  32
  33         if (!nvdimm_bus)
  34                 return;
  35         mutex_lock(&nvdimm_bus->reconfig_mutex);
  36 }
  37 EXPORT_SYMBOL(nvdimm_bus_lock);
  38
  39 void nvdimm_bus_unlock(struct device *dev)
  40 {
  41         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
  42
  43         if (!nvdimm_bus)
  44                 return;
  45         mutex_unlock(&nvdimm_bus->reconfig_mutex);
  46 }
  47 EXPORT_SYMBOL(nvdimm_bus_unlock);
  48
  49 bool is_nvdimm_bus_locked(struct device *dev)
  50 {
  51         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
  52
  53         if (!nvdimm_bus)
  54                 return false;
  55         return mutex_is_locked(&nvdimm_bus->reconfig_mutex);
  56 }
  57 EXPORT_SYMBOL(is_nvdimm_bus_locked);
  58
  59 u64 nd_fletcher64(void *addr, size_t len, bool le)
  60 {
  61         u32 *buf = addr;
  62         u32 lo32 = 0;
  63         u64 hi32 = 0;
  64         int i;
  65
  66         for (i = 0; i < len / sizeof(u32); i++) {
  67                 lo32 += le ? le32_to_cpu((__le32) buf[i]) : buf[i];
  68                 hi32 += lo32;
  69         }
  70
  71         return hi32 << 32 | lo32;
  72 }
  73 EXPORT_SYMBOL_GPL(nd_fletcher64);
  74
  75 static void nvdimm_bus_release(struct device *dev)
  76 {
  77         struct nvdimm_bus *nvdimm_bus;
  78
  79         nvdimm_bus = container_of(dev, struct nvdimm_bus, dev);
  80         ida_simple_remove(&nd_ida, nvdimm_bus->id);
  81         kfree(nvdimm_bus);
  82 }
  83
  84 struct nvdimm_bus *to_nvdimm_bus(struct device *dev)
  85 {
  86         struct nvdimm_bus *nvdimm_bus;
  87
  88         nvdimm_bus = container_of(dev, struct nvdimm_bus, dev);
  89         WARN_ON(nvdimm_bus->dev.release != nvdimm_bus_release);
  90         return nvdimm_bus;
  91 }
  92 EXPORT_SYMBOL_GPL(to_nvdimm_bus);
  93
  94 struct nvdimm_bus_descriptor *to_nd_desc(struct nvdimm_bus *nvdimm_bus)
  95 {
  96         /* struct nvdimm_bus definition is private to libnvdimm */
  97         return nvdimm_bus->nd_desc;
  98 }
  99 EXPORT_SYMBOL_GPL(to_nd_desc);
 100
 101 struct nvdimm_bus *walk_to_nvdimm_bus(struct device *nd_dev)
 102 {
 103         struct device *dev;
 104
 105         for (dev = nd_dev; dev; dev = dev->parent)
 106                 if (dev->release == nvdimm_bus_release)
 107                         break;
 108         dev_WARN_ONCE(nd_dev, !dev, "invalid dev, not on nd bus\n");
 109         if (dev)
 110                 return to_nvdimm_bus(dev);
 111         return NULL;
 112 }
 113
 114 static bool is_uuid_sep(char sep)
 115 {
 116         if (sep == '\n' || sep == '-' || sep == ':' || sep == '\0')
 117                 return true;
 118         return false;
 119 }
 120
 121 static int nd_uuid_parse(struct device *dev, u8 *uuid_out, const char *buf,
 122                 size_t len)
 123 {
 124         const char *str = buf;
 125         u8 uuid[16];
 126         int i;
 127
 128         for (i = 0; i < 16; i++) {
 129                 if (!isxdigit(str[0]) || !isxdigit(str[1])) {
 130                         dev_dbg(dev, "%s: pos: %d buf[%zd]: %c buf[%zd]: %c\n",
 131                                         __func__, i, str - buf, str[0],
 132                                         str + 1 - buf, str[1]);
 133                         return -EINVAL;
 134                 }
 135
 136                 uuid[i] = (hex_to_bin(str[0]) << 4) | hex_to_bin(str[1]);
 137                 str += 2;
 138                 if (is_uuid_sep(*str))
 139                         str++;
 140         }
 141
 142         memcpy(uuid_out, uuid, sizeof(uuid));
 143         return 0;
 144 }
 145
 146 /**
 147  * nd_uuid_store: common implementation for writing 'uuid' sysfs attributes
 148  * @dev: container device for the uuid property
 149  * @uuid_out: uuid buffer to replace
 150  * @buf: raw sysfs buffer to parse
 151  *
 152  * Enforce that uuids can only be changed while the device is disabled
 153  * (driver detached)
 154  * LOCKING: expects device_lock() is held on entry
 155  */
 156 int nd_uuid_store(struct device *dev, u8 **uuid_out, const char *buf,
 157                 size_t len)
 158 {
 159         u8 uuid[16];
 160         int rc;
 161
 162         if (dev->driver)
 163                 return -EBUSY;
 164
 165         rc = nd_uuid_parse(dev, uuid, buf, len);
 166         if (rc)
 167                 return rc;
 168
 169         kfree(*uuid_out);
 170         *uuid_out = kmemdup(uuid, sizeof(uuid), GFP_KERNEL);
 171         if (!(*uuid_out))
 172                 return -ENOMEM;
 173
 174         return 0;
 175 }
 176
 177 ssize_t nd_sector_size_show(unsigned long current_lbasize,
 178                 const unsigned long *supported, char *buf)
 179 {
 180         ssize_t len = 0;
 181         int i;
 182
 183         for (i = 0; supported[i]; i++)
 184                 if (current_lbasize == supported[i])
 185                         len += sprintf(buf + len, "[%ld] ", supported[i]);
 186                 else
 187                         len += sprintf(buf + len, "%ld ", supported[i]);
 188         len += sprintf(buf + len, "\n");
 189         return len;
 190 }
 191
 192 ssize_t nd_sector_size_store(struct device *dev, const char *buf,
 193                 unsigned long *current_lbasize, const unsigned long *supported)
 194 {
 195         unsigned long lbasize;
 196         int rc, i;
 197
 198         if (dev->driver)
 199                 return -EBUSY;
 200
 201         rc = kstrtoul(buf, 0, &lbasize);
 202         if (rc)
 203                 return rc;
 204
 205         for (i = 0; supported[i]; i++)
 206                 if (lbasize == supported[i])
 207                         break;
 208
 209         if (supported[i]) {
 210                 *current_lbasize = lbasize;
 211                 return 0;
 212         } else {
 213                 return -EINVAL;
 214         }
 215 }
 216
 217 static ssize_t commands_show(struct device *dev,
 218                 struct device_attribute *attr, char *buf)
 219 {
 220         int cmd, len = 0;
 221         struct nvdimm_bus *nvdimm_bus = to_nvdimm_bus(dev);
 222         struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
 223
 224         for_each_set_bit(cmd, &nd_desc->dsm_mask, BITS_PER_LONG)
 225                 len += sprintf(buf + len, "%s ", nvdimm_bus_cmd_name(cmd));
 226         len += sprintf(buf + len, "\n");
 227         return len;
 228 }
 229 static DEVICE_ATTR_RO(commands);
 230
 231 static const char *nvdimm_bus_provider(struct nvdimm_bus *nvdimm_bus)
 232 {
 233         struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
 234         struct device *parent = nvdimm_bus->dev.parent;
 235
 236         if (nd_desc->provider_name)
 237                 return nd_desc->provider_name;
 238         else if (parent)
 239                 return dev_name(parent);
 240         else
 241                 return "unknown";
 242 }
 243
 244 static ssize_t provider_show(struct device *dev,
 245                 struct device_attribute *attr, char *buf)
 246 {
 247         struct nvdimm_bus *nvdimm_bus = to_nvdimm_bus(dev);
 248
 249         return sprintf(buf, "%s\n", nvdimm_bus_provider(nvdimm_bus));
 250 }
 251 static DEVICE_ATTR_RO(provider);
 252
 253 static int flush_namespaces(struct device *dev, void *data)
 254 {
 255         device_lock(dev);
 256         device_unlock(dev);
 257         return 0;
 258 }
 259
 260 static int flush_regions_dimms(struct device *dev, void *data)
 261 {
 262         device_lock(dev);
 263         device_unlock(dev);
 264         device_for_each_child(dev, NULL, flush_namespaces);
 265         return 0;
 266 }
 267
 268 static ssize_t wait_probe_show(struct device *dev,
 269                 struct device_attribute *attr, char *buf)
 270 {
 271         nd_synchronize();
 272         device_for_each_child(dev, NULL, flush_regions_dimms);
 273         return sprintf(buf, "1\n");
 274 }
 275 static DEVICE_ATTR_RO(wait_probe);
 276
 277 static struct attribute *nvdimm_bus_attributes[] = {
 278         &dev_attr_commands.attr,
 279         &dev_attr_wait_probe.attr,
 280         &dev_attr_provider.attr,
 281         NULL,
 282 };
 283
 284 struct attribute_group nvdimm_bus_attribute_group = {
 285         .attrs = nvdimm_bus_attributes,
 286 };
 287 EXPORT_SYMBOL_GPL(nvdimm_bus_attribute_group);
 288
 289 struct nvdimm_bus *__nvdimm_bus_register(struct device *parent,
 290                 struct nvdimm_bus_descriptor *nd_desc, struct module *module)
 291 {
 292         struct nvdimm_bus *nvdimm_bus;
 293         int rc;
 294
 295         nvdimm_bus = kzalloc(sizeof(*nvdimm_bus), GFP_KERNEL);
 296         if (!nvdimm_bus)
 297                 return NULL;
 298         INIT_LIST_HEAD(&nvdimm_bus->list);
 299         init_waitqueue_head(&nvdimm_bus->probe_wait);
 300         nvdimm_bus->id = ida_simple_get(&nd_ida, 0, 0, GFP_KERNEL);
 301         mutex_init(&nvdimm_bus->reconfig_mutex);
 302         if (nvdimm_bus->id < 0) {
 303                 kfree(nvdimm_bus);
 304                 return NULL;
 305         }
 306         nvdimm_bus->nd_desc = nd_desc;
 307         nvdimm_bus->module = module;
 308         nvdimm_bus->dev.parent = parent;
 309         nvdimm_bus->dev.release = nvdimm_bus_release;
 310         nvdimm_bus->dev.groups = nd_desc->attr_groups;
 311         dev_set_name(&nvdimm_bus->dev, "ndbus%d", nvdimm_bus->id);
 312         rc = device_register(&nvdimm_bus->dev);
 313         if (rc) {
 314                 dev_dbg(&nvdimm_bus->dev, "registration failed: %d\n", rc);
 315                 goto err;
 316         }
 317
 318         rc = nvdimm_bus_create_ndctl(nvdimm_bus);
 319         if (rc)
 320                 goto err;
 321
 322         mutex_lock(&nvdimm_bus_list_mutex);
 323         list_add_tail(&nvdimm_bus->list, &nvdimm_bus_list);
 324         mutex_unlock(&nvdimm_bus_list_mutex);
 325
 326         return nvdimm_bus;
 327  err:
 328         put_device(&nvdimm_bus->dev);
 329         return NULL;
 330 }
 331 EXPORT_SYMBOL_GPL(__nvdimm_bus_register);
 332
 333 static int child_unregister(struct device *dev, void *data)
 334 {
 335         /*
 336          * the singular ndctl class device per bus needs to be
 337          * "device_destroy"ed, so skip it here
 338          *
 339          * i.e. remove classless children
 340          */
 341         if (dev->class)
 342                 /* pass */;
 343         else
 344                 nd_device_unregister(dev, ND_SYNC);
 345         return 0;
 346 }
 347
 348 void nvdimm_bus_unregister(struct nvdimm_bus *nvdimm_bus)
 349 {
 350         if (!nvdimm_bus)
 351                 return;
 352
 353         mutex_lock(&nvdimm_bus_list_mutex);
 354         list_del_init(&nvdimm_bus->list);
 355         mutex_unlock(&nvdimm_bus_list_mutex);
 356
 357         nd_synchronize();
 358         device_for_each_child(&nvdimm_bus->dev, NULL, child_unregister);
 359         nvdimm_bus_destroy_ndctl(nvdimm_bus);
 360
 361         device_unregister(&nvdimm_bus->dev);
 362 }
 363 EXPORT_SYMBOL_GPL(nvdimm_bus_unregister);
 364
 365 #ifdef CONFIG_BLK_DEV_INTEGRITY
 366 static int nd_pi_nop_generate_verify(struct blk_integrity_iter *iter)
 367 {
 368         return 0;
 369 }
 370
 371 int nd_integrity_init(struct gendisk *disk, unsigned long meta_size)
 372 {
 373         struct blk_integrity integrity = {
 374                 .name = "ND-PI-NOP",
 375                 .generate_fn = nd_pi_nop_generate_verify,
 376                 .verify_fn = nd_pi_nop_generate_verify,
 377                 .tuple_size = meta_size,
 378                 .tag_size = meta_size,
 379         };
 380         int ret;
 381
 382         if (meta_size == 0)
 383                 return 0;
 384
 385         ret = blk_integrity_register(disk, &integrity);
 386         if (ret)
 387                 return ret;
 388
 389         blk_queue_max_integrity_segments(disk->queue, 1);
 390
 391         return 0;
 392 }
 393 EXPORT_SYMBOL(nd_integrity_init);
 394
 395 #else /* CONFIG_BLK_DEV_INTEGRITY */
 396 int nd_integrity_init(struct gendisk *disk, unsigned long meta_size)
 397 {
 398         return 0;
 399 }
 400 EXPORT_SYMBOL(nd_integrity_init);
 401
 402 #endif
 403
 404 static __init int libnvdimm_init(void)
 405 {
 406         int rc;
 407
 408         rc = nvdimm_bus_init();
 409         if (rc)
 410                 return rc;
 411         rc = nvdimm_init();
 412         if (rc)
 413                 goto err_dimm;
 414         rc = nd_region_init();
 415         if (rc)
 416                 goto err_region;
 417         return 0;
 418  err_region:
 419         nvdimm_exit();
 420  err_dimm:
 421         nvdimm_bus_exit();
 422         return rc;
 423 }
 424
 425 static __exit void libnvdimm_exit(void)
 426 {
 427         WARN_ON(!list_empty(&nvdimm_bus_list));
 428         nd_region_exit();
 429         nvdimm_exit();
 430         nvdimm_bus_exit();
 431 }
 432
 433 MODULE_LICENSE("GPL v2");
 434 MODULE_AUTHOR("Intel Corporation");
 435 subsys_initcall(libnvdimm_init);
 436 module_exit(libnvdimm_exit);