drivers/nvdimm/bus.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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  14 #include <linux/vmalloc.h>
  15 #include <linux/uaccess.h>
  16 #include <linux/module.h>
  17 #include <linux/blkdev.h>
  18 #include <linux/fcntl.h>
  19 #include <linux/async.h>
  20 #include <linux/genhd.h>
  21 #include <linux/ndctl.h>
  22 #include <linux/sched.h>
  23 #include <linux/slab.h>
  24 #include <linux/fs.h>
  25 #include <linux/io.h>
  26 #include <linux/mm.h>
  27 #include <linux/nd.h>
  28 #include "nd-core.h"
  29 #include "nd.h"
  30
  31 int nvdimm_major;
  32 static int nvdimm_bus_major;
  33 static struct class *nd_class;
  34
  35 static int to_nd_device_type(struct device *dev)
  36 {
  37         if (is_nvdimm(dev))
  38                 return ND_DEVICE_DIMM;
  39         else if (is_nd_pmem(dev))
  40                 return ND_DEVICE_REGION_PMEM;
  41         else if (is_nd_blk(dev))
  42                 return ND_DEVICE_REGION_BLK;
  43         else if (is_nd_dax(dev))
  44                 return ND_DEVICE_DAX_PMEM;
  45         else if (is_nd_pmem(dev->parent) || is_nd_blk(dev->parent))
  46                 return nd_region_to_nstype(to_nd_region(dev->parent));
  47
  48         return 0;
  49 }
  50
  51 static int nvdimm_bus_uevent(struct device *dev, struct kobj_uevent_env *env)
  52 {
  53         /*
  54          * Ensure that region devices always have their numa node set as
  55          * early as possible.
  56          */
  57         if (is_nd_pmem(dev) || is_nd_blk(dev))
  58                 set_dev_node(dev, to_nd_region(dev)->numa_node);
  59         return add_uevent_var(env, "MODALIAS=" ND_DEVICE_MODALIAS_FMT,
  60                         to_nd_device_type(dev));
  61 }
  62
  63 static int nvdimm_bus_match(struct device *dev, struct device_driver *drv)
  64 {
  65         struct nd_device_driver *nd_drv = to_nd_device_driver(drv);
  66
  67         return !!test_bit(to_nd_device_type(dev), &nd_drv->type);
  68 }
  69
  70 static struct module *to_bus_provider(struct device *dev)
  71 {
  72         /* pin bus providers while regions are enabled */
  73         if (is_nd_pmem(dev) || is_nd_blk(dev)) {
  74                 struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
  75
  76                 return nvdimm_bus->module;
  77         }
  78         return NULL;
  79 }
  80
  81 static void nvdimm_bus_probe_start(struct nvdimm_bus *nvdimm_bus)
  82 {
  83         nvdimm_bus_lock(&nvdimm_bus->dev);
  84         nvdimm_bus->probe_active++;
  85         nvdimm_bus_unlock(&nvdimm_bus->dev);
  86 }
  87
  88 static void nvdimm_bus_probe_end(struct nvdimm_bus *nvdimm_bus)
  89 {
  90         nvdimm_bus_lock(&nvdimm_bus->dev);
  91         if (--nvdimm_bus->probe_active == 0)
  92                 wake_up(&nvdimm_bus->probe_wait);
  93         nvdimm_bus_unlock(&nvdimm_bus->dev);
  94 }
  95
  96 static int nvdimm_bus_probe(struct device *dev)
  97 {
  98         struct nd_device_driver *nd_drv = to_nd_device_driver(dev->driver);
  99         struct module *provider = to_bus_provider(dev);
 100         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
 101         int rc;
 102
 103         if (!try_module_get(provider))
 104                 return -ENXIO;
 105
 106         nvdimm_bus_probe_start(nvdimm_bus);
 107         rc = nd_drv->probe(dev);
 108         if (rc == 0)
 109                 nd_region_probe_success(nvdimm_bus, dev);
 110         else
 111                 nd_region_disable(nvdimm_bus, dev);
 112         nvdimm_bus_probe_end(nvdimm_bus);
 113
 114         dev_dbg(&nvdimm_bus->dev, "%s.probe(%s) = %d\n", dev->driver->name,
 115                         dev_name(dev), rc);
 116
 117         if (rc != 0)
 118                 module_put(provider);
 119         return rc;
 120 }
 121
 122 static int nvdimm_bus_remove(struct device *dev)
 123 {
 124         struct nd_device_driver *nd_drv = to_nd_device_driver(dev->driver);
 125         struct module *provider = to_bus_provider(dev);
 126         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
 127         int rc;
 128
 129         rc = nd_drv->remove(dev);
 130         nd_region_disable(nvdimm_bus, dev);
 131
 132         dev_dbg(&nvdimm_bus->dev, "%s.remove(%s) = %d\n", dev->driver->name,
 133                         dev_name(dev), rc);
 134         module_put(provider);
 135         return rc;
 136 }
 137
 138 void nd_device_notify(struct device *dev, enum nvdimm_event event)
 139 {
 140         device_lock(dev);
 141         if (dev->driver) {
 142                 struct nd_device_driver *nd_drv;
 143
 144                 nd_drv = to_nd_device_driver(dev->driver);
 145                 if (nd_drv->notify)
 146                         nd_drv->notify(dev, event);
 147         }
 148         device_unlock(dev);
 149 }
 150 EXPORT_SYMBOL(nd_device_notify);
 151
 152 void nvdimm_region_notify(struct nd_region *nd_region, enum nvdimm_event event)
 153 {
 154         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(&nd_region->dev);
 155
 156         if (!nvdimm_bus)
 157                 return;
 158
 159         /* caller is responsible for holding a reference on the device */
 160         nd_device_notify(&nd_region->dev, event);
 161 }
 162 EXPORT_SYMBOL_GPL(nvdimm_region_notify);
 163
 164 long nvdimm_clear_poison(struct device *dev, phys_addr_t phys,
 165                 unsigned int len)
 166 {
 167         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
 168         struct nvdimm_bus_descriptor *nd_desc;
 169         struct nd_cmd_clear_error clear_err;
 170         struct nd_cmd_ars_cap ars_cap;
 171         u32 clear_err_unit, mask;
 172         int cmd_rc, rc;
 173
 174         if (!nvdimm_bus)
 175                 return -ENXIO;
 176
 177         nd_desc = nvdimm_bus->nd_desc;
 178         if (!nd_desc->ndctl)
 179                 return -ENXIO;
 180
 181         memset(&ars_cap, 0, sizeof(ars_cap));
 182         ars_cap.address = phys;
 183         ars_cap.length = len;
 184         rc = nd_desc->ndctl(nd_desc, NULL, ND_CMD_ARS_CAP, &ars_cap,
 185                         sizeof(ars_cap), &cmd_rc);
 186         if (rc < 0)
 187                 return rc;
 188         if (cmd_rc < 0)
 189                 return cmd_rc;
 190         clear_err_unit = ars_cap.clear_err_unit;
 191         if (!clear_err_unit || !is_power_of_2(clear_err_unit))
 192                 return -ENXIO;
 193
 194         mask = clear_err_unit - 1;
 195         if ((phys | len) & mask)
 196                 return -ENXIO;
 197         memset(&clear_err, 0, sizeof(clear_err));
 198         clear_err.address = phys;
 199         clear_err.length = len;
 200         rc = nd_desc->ndctl(nd_desc, NULL, ND_CMD_CLEAR_ERROR, &clear_err,
 201                         sizeof(clear_err), &cmd_rc);
 202         if (rc < 0)
 203                 return rc;
 204         if (cmd_rc < 0)
 205                 return cmd_rc;
 206         return clear_err.cleared;
 207 }
 208 EXPORT_SYMBOL_GPL(nvdimm_clear_poison);
 209
 210 static struct bus_type nvdimm_bus_type = {
 211         .name = "nd",
 212         .uevent = nvdimm_bus_uevent,
 213         .match = nvdimm_bus_match,
 214         .probe = nvdimm_bus_probe,
 215         .remove = nvdimm_bus_remove,
 216 };
 217
 218 static ASYNC_DOMAIN_EXCLUSIVE(nd_async_domain);
 219
 220 void nd_synchronize(void)
 221 {
 222         async_synchronize_full_domain(&nd_async_domain);
 223 }
 224 EXPORT_SYMBOL_GPL(nd_synchronize);
 225
 226 static void nd_async_device_register(void *d, async_cookie_t cookie)
 227 {
 228         struct device *dev = d;
 229
 230         if (device_add(dev) != 0) {
 231                 dev_err(dev, "%s: failed\n", __func__);
 232                 put_device(dev);
 233         }
 234         put_device(dev);
 235 }
 236
 237 static void nd_async_device_unregister(void *d, async_cookie_t cookie)
 238 {
 239         struct device *dev = d;
 240
 241         /* flush bus operations before delete */
 242         nvdimm_bus_lock(dev);
 243         nvdimm_bus_unlock(dev);
 244
 245         device_unregister(dev);
 246         put_device(dev);
 247 }
 248
 249 void __nd_device_register(struct device *dev)
 250 {
 251         if (!dev)
 252                 return;
 253         dev->bus = &nvdimm_bus_type;
 254         get_device(dev);
 255         async_schedule_domain(nd_async_device_register, dev,
 256                         &nd_async_domain);
 257 }
 258
 259 void nd_device_register(struct device *dev)
 260 {
 261         device_initialize(dev);
 262         __nd_device_register(dev);
 263 }
 264 EXPORT_SYMBOL(nd_device_register);
 265
 266 void nd_device_unregister(struct device *dev, enum nd_async_mode mode)
 267 {
 268         switch (mode) {
 269         case ND_ASYNC:
 270                 get_device(dev);
 271                 async_schedule_domain(nd_async_device_unregister, dev,
 272                                 &nd_async_domain);
 273                 break;
 274         case ND_SYNC:
 275                 nd_synchronize();
 276                 device_unregister(dev);
 277                 break;
 278         }
 279 }
 280 EXPORT_SYMBOL(nd_device_unregister);
 281
 282 /**
 283  * __nd_driver_register() - register a region or a namespace driver
 284  * @nd_drv: driver to register
 285  * @owner: automatically set by nd_driver_register() macro
 286  * @mod_name: automatically set by nd_driver_register() macro
 287  */
 288 int __nd_driver_register(struct nd_device_driver *nd_drv, struct module *owner,
 289                 const char *mod_name)
 290 {
 291         struct device_driver *drv = &nd_drv->drv;
 292
 293         if (!nd_drv->type) {
 294                 pr_debug("driver type bitmask not set (%pf)\n",
 295                                 __builtin_return_address(0));
 296                 return -EINVAL;
 297         }
 298
 299         if (!nd_drv->probe || !nd_drv->remove) {
 300                 pr_debug("->probe() and ->remove() must be specified\n");
 301                 return -EINVAL;
 302         }
 303
 304         drv->bus = &nvdimm_bus_type;
 305         drv->owner = owner;
 306         drv->mod_name = mod_name;
 307
 308         return driver_register(drv);
 309 }
 310 EXPORT_SYMBOL(__nd_driver_register);
 311
 312 int nvdimm_revalidate_disk(struct gendisk *disk)
 313 {
 314         struct device *dev = disk->driverfs_dev;
 315         struct nd_region *nd_region = to_nd_region(dev->parent);
 316         const char *pol = nd_region->ro ? "only" : "write";
 317
 318         if (nd_region->ro == get_disk_ro(disk))
 319                 return 0;
 320
 321         dev_info(dev, "%s read-%s, marking %s read-%s\n",
 322                         dev_name(&nd_region->dev), pol, disk->disk_name, pol);
 323         set_disk_ro(disk, nd_region->ro);
 324
 325         return 0;
 326
 327 }
 328 EXPORT_SYMBOL(nvdimm_revalidate_disk);
 329
 330 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
 331                 char *buf)
 332 {
 333         return sprintf(buf, ND_DEVICE_MODALIAS_FMT "\n",
 334                         to_nd_device_type(dev));
 335 }
 336 static DEVICE_ATTR_RO(modalias);
 337
 338 static ssize_t devtype_show(struct device *dev, struct device_attribute *attr,
 339                 char *buf)
 340 {
 341         return sprintf(buf, "%s\n", dev->type->name);
 342 }
 343 static DEVICE_ATTR_RO(devtype);
 344
 345 static struct attribute *nd_device_attributes[] = {
 346         &dev_attr_modalias.attr,
 347         &dev_attr_devtype.attr,
 348         NULL,
 349 };
 350
 351 /**
 352  * nd_device_attribute_group - generic attributes for all devices on an nd bus
 353  */
 354 struct attribute_group nd_device_attribute_group = {
 355         .attrs = nd_device_attributes,
 356 };
 357 EXPORT_SYMBOL_GPL(nd_device_attribute_group);
 358
 359 static ssize_t numa_node_show(struct device *dev,
 360                 struct device_attribute *attr, char *buf)
 361 {
 362         return sprintf(buf, "%d\n", dev_to_node(dev));
 363 }
 364 static DEVICE_ATTR_RO(numa_node);
 365
 366 static struct attribute *nd_numa_attributes[] = {
 367         &dev_attr_numa_node.attr,
 368         NULL,
 369 };
 370
 371 static umode_t nd_numa_attr_visible(struct kobject *kobj, struct attribute *a,
 372                 int n)
 373 {
 374         if (!IS_ENABLED(CONFIG_NUMA))
 375                 return 0;
 376
 377         return a->mode;
 378 }
 379
 380 /**
 381  * nd_numa_attribute_group - NUMA attributes for all devices on an nd bus
 382  */
 383 struct attribute_group nd_numa_attribute_group = {
 384         .attrs = nd_numa_attributes,
 385         .is_visible = nd_numa_attr_visible,
 386 };
 387 EXPORT_SYMBOL_GPL(nd_numa_attribute_group);
 388
 389 int nvdimm_bus_create_ndctl(struct nvdimm_bus *nvdimm_bus)
 390 {
 391         dev_t devt = MKDEV(nvdimm_bus_major, nvdimm_bus->id);
 392         struct device *dev;
 393
 394         dev = device_create(nd_class, &nvdimm_bus->dev, devt, nvdimm_bus,
 395                         "ndctl%d", nvdimm_bus->id);
 396
 397         if (IS_ERR(dev)) {
 398                 dev_dbg(&nvdimm_bus->dev, "failed to register ndctl%d: %ld\n",
 399                                 nvdimm_bus->id, PTR_ERR(dev));
 400                 return PTR_ERR(dev);
 401         }
 402         return 0;
 403 }
 404
 405 void nvdimm_bus_destroy_ndctl(struct nvdimm_bus *nvdimm_bus)
 406 {
 407         device_destroy(nd_class, MKDEV(nvdimm_bus_major, nvdimm_bus->id));
 408 }
 409
 410 static const struct nd_cmd_desc __nd_cmd_dimm_descs[] = {
 411         [ND_CMD_IMPLEMENTED] = { },
 412         [ND_CMD_SMART] = {
 413                 .out_num = 2,
 414                 .out_sizes = { 4, 128, },
 415         },
 416         [ND_CMD_SMART_THRESHOLD] = {
 417                 .out_num = 2,
 418                 .out_sizes = { 4, 8, },
 419         },
 420         [ND_CMD_DIMM_FLAGS] = {
 421                 .out_num = 2,
 422                 .out_sizes = { 4, 4 },
 423         },
 424         [ND_CMD_GET_CONFIG_SIZE] = {
 425                 .out_num = 3,
 426                 .out_sizes = { 4, 4, 4, },
 427         },
 428         [ND_CMD_GET_CONFIG_DATA] = {
 429                 .in_num = 2,
 430                 .in_sizes = { 4, 4, },
 431                 .out_num = 2,
 432                 .out_sizes = { 4, UINT_MAX, },
 433         },
 434         [ND_CMD_SET_CONFIG_DATA] = {
 435                 .in_num = 3,
 436                 .in_sizes = { 4, 4, UINT_MAX, },
 437                 .out_num = 1,
 438                 .out_sizes = { 4, },
 439         },
 440         [ND_CMD_VENDOR] = {
 441                 .in_num = 3,
 442                 .in_sizes = { 4, 4, UINT_MAX, },
 443                 .out_num = 3,
 444                 .out_sizes = { 4, 4, UINT_MAX, },
 445         },
 446 };
 447
 448 const struct nd_cmd_desc *nd_cmd_dimm_desc(int cmd)
 449 {
 450         if (cmd < ARRAY_SIZE(__nd_cmd_dimm_descs))
 451                 return &__nd_cmd_dimm_descs[cmd];
 452         return NULL;
 453 }
 454 EXPORT_SYMBOL_GPL(nd_cmd_dimm_desc);
 455
 456 static const struct nd_cmd_desc __nd_cmd_bus_descs[] = {
 457         [ND_CMD_IMPLEMENTED] = { },
 458         [ND_CMD_ARS_CAP] = {
 459                 .in_num = 2,
 460                 .in_sizes = { 8, 8, },
 461                 .out_num = 4,
 462                 .out_sizes = { 4, 4, 4, 4, },
 463         },
 464         [ND_CMD_ARS_START] = {
 465                 .in_num = 5,
 466                 .in_sizes = { 8, 8, 2, 1, 5, },
 467                 .out_num = 2,
 468                 .out_sizes = { 4, 4, },
 469         },
 470         [ND_CMD_ARS_STATUS] = {
 471                 .out_num = 3,
 472                 .out_sizes = { 4, 4, UINT_MAX, },
 473         },
 474         [ND_CMD_CLEAR_ERROR] = {
 475                 .in_num = 2,
 476                 .in_sizes = { 8, 8, },
 477                 .out_num = 3,
 478                 .out_sizes = { 4, 4, 8, },
 479         },
 480 };
 481
 482 const struct nd_cmd_desc *nd_cmd_bus_desc(int cmd)
 483 {
 484         if (cmd < ARRAY_SIZE(__nd_cmd_bus_descs))
 485                 return &__nd_cmd_bus_descs[cmd];
 486         return NULL;
 487 }
 488 EXPORT_SYMBOL_GPL(nd_cmd_bus_desc);
 489
 490 u32 nd_cmd_in_size(struct nvdimm *nvdimm, int cmd,
 491                 const struct nd_cmd_desc *desc, int idx, void *buf)
 492 {
 493         if (idx >= desc->in_num)
 494                 return UINT_MAX;
 495
 496         if (desc->in_sizes[idx] < UINT_MAX)
 497                 return desc->in_sizes[idx];
 498
 499         if (nvdimm && cmd == ND_CMD_SET_CONFIG_DATA && idx == 2) {
 500                 struct nd_cmd_set_config_hdr *hdr = buf;
 501
 502                 return hdr->in_length;
 503         } else if (nvdimm && cmd == ND_CMD_VENDOR && idx == 2) {
 504                 struct nd_cmd_vendor_hdr *hdr = buf;
 505
 506                 return hdr->in_length;
 507         }
 508
 509         return UINT_MAX;
 510 }
 511 EXPORT_SYMBOL_GPL(nd_cmd_in_size);
 512
 513 u32 nd_cmd_out_size(struct nvdimm *nvdimm, int cmd,
 514                 const struct nd_cmd_desc *desc, int idx, const u32 *in_field,
 515                 const u32 *out_field)
 516 {
 517         if (idx >= desc->out_num)
 518                 return UINT_MAX;
 519
 520         if (desc->out_sizes[idx] < UINT_MAX)
 521                 return desc->out_sizes[idx];
 522
 523         if (nvdimm && cmd == ND_CMD_GET_CONFIG_DATA && idx == 1)
 524                 return in_field[1];
 525         else if (nvdimm && cmd == ND_CMD_VENDOR && idx == 2)
 526                 return out_field[1];
 527         else if (!nvdimm && cmd == ND_CMD_ARS_STATUS && idx == 2)
 528                 return out_field[1] - 8;
 529
 530         return UINT_MAX;
 531 }
 532 EXPORT_SYMBOL_GPL(nd_cmd_out_size);
 533
 534 void wait_nvdimm_bus_probe_idle(struct device *dev)
 535 {
 536         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
 537
 538         do {
 539                 if (nvdimm_bus->probe_active == 0)
 540                         break;
 541                 nvdimm_bus_unlock(&nvdimm_bus->dev);
 542                 wait_event(nvdimm_bus->probe_wait,
 543                                 nvdimm_bus->probe_active == 0);
 544                 nvdimm_bus_lock(&nvdimm_bus->dev);
 545         } while (true);
 546 }
 547
 548 static int pmem_active(struct device *dev, void *data)
 549 {
 550         if (is_nd_pmem(dev) && dev->driver)
 551                 return -EBUSY;
 552         return 0;
 553 }
 554
 555 /* set_config requires an idle interleave set */
 556 static int nd_cmd_clear_to_send(struct nvdimm_bus *nvdimm_bus,
 557                 struct nvdimm *nvdimm, unsigned int cmd)
 558 {
 559         struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
 560
 561         /* ask the bus provider if it would like to block this request */
 562         if (nd_desc->clear_to_send) {
 563                 int rc = nd_desc->clear_to_send(nd_desc, nvdimm, cmd);
 564
 565                 if (rc)
 566                         return rc;
 567         }
 568
 569         /* require clear error to go through the pmem driver */
 570         if (!nvdimm && cmd == ND_CMD_CLEAR_ERROR)
 571                 return device_for_each_child(&nvdimm_bus->dev, NULL,
 572                                 pmem_active);
 573
 574         if (!nvdimm || cmd != ND_CMD_SET_CONFIG_DATA)
 575                 return 0;
 576
 577         /* prevent label manipulation while the kernel owns label updates */
 578         wait_nvdimm_bus_probe_idle(&nvdimm_bus->dev);
 579         if (atomic_read(&nvdimm->busy))
 580                 return -EBUSY;
 581         return 0;
 582 }
 583
 584 static int __nd_ioctl(struct nvdimm_bus *nvdimm_bus, struct nvdimm *nvdimm,
 585                 int read_only, unsigned int ioctl_cmd, unsigned long arg)
 586 {
 587         struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
 588         size_t buf_len = 0, in_len = 0, out_len = 0;
 589         static char out_env[ND_CMD_MAX_ENVELOPE];
 590         static char in_env[ND_CMD_MAX_ENVELOPE];
 591         const struct nd_cmd_desc *desc = NULL;
 592         unsigned int cmd = _IOC_NR(ioctl_cmd);
 593         void __user *p = (void __user *) arg;
 594         struct device *dev = &nvdimm_bus->dev;
 595         const char *cmd_name, *dimm_name;
 596         unsigned long dsm_mask;
 597         void *buf;
 598         int rc, i;
 599
 600         if (nvdimm) {
 601                 desc = nd_cmd_dimm_desc(cmd);
 602                 cmd_name = nvdimm_cmd_name(cmd);
 603                 dsm_mask = nvdimm->dsm_mask ? *(nvdimm->dsm_mask) : 0;
 604                 dimm_name = dev_name(&nvdimm->dev);
 605         } else {
 606                 desc = nd_cmd_bus_desc(cmd);
 607                 cmd_name = nvdimm_bus_cmd_name(cmd);
 608                 dsm_mask = nd_desc->dsm_mask;
 609                 dimm_name = "bus";
 610         }
 611
 612         if (!desc || (desc->out_num + desc->in_num == 0) ||
 613                         !test_bit(cmd, &dsm_mask))
 614                 return -ENOTTY;
 615
 616         /* fail write commands (when read-only) */
 617         if (read_only)
 618                 switch (cmd) {
 619                 case ND_CMD_VENDOR:
 620                 case ND_CMD_SET_CONFIG_DATA:
 621                 case ND_CMD_ARS_START:
 622                 case ND_CMD_CLEAR_ERROR:
 623                         dev_dbg(&nvdimm_bus->dev, "'%s' command while read-only.\n",
 624                                         nvdimm ? nvdimm_cmd_name(cmd)
 625                                         : nvdimm_bus_cmd_name(cmd));
 626                         return -EPERM;
 627                 default:
 628                         break;
 629                 }
 630
 631         /* process an input envelope */
 632         for (i = 0; i < desc->in_num; i++) {
 633                 u32 in_size, copy;
 634
 635                 in_size = nd_cmd_in_size(nvdimm, cmd, desc, i, in_env);
 636                 if (in_size == UINT_MAX) {
 637                         dev_err(dev, "%s:%s unknown input size cmd: %s field: %d\n",
 638                                         __func__, dimm_name, cmd_name, i);
 639                         return -ENXIO;
 640                 }
 641                 if (in_len < sizeof(in_env))
 642                         copy = min_t(u32, sizeof(in_env) - in_len, in_size);
 643                 else
 644                         copy = 0;
 645                 if (copy && copy_from_user(&in_env[in_len], p + in_len, copy))
 646                         return -EFAULT;
 647                 in_len += in_size;
 648         }
 649
 650         /* process an output envelope */
 651         for (i = 0; i < desc->out_num; i++) {
 652                 u32 out_size = nd_cmd_out_size(nvdimm, cmd, desc, i,
 653                                 (u32 *) in_env, (u32 *) out_env);
 654                 u32 copy;
 655
 656                 if (out_size == UINT_MAX) {
 657                         dev_dbg(dev, "%s:%s unknown output size cmd: %s field: %d\n",
 658                                         __func__, dimm_name, cmd_name, i);
 659                         return -EFAULT;
 660                 }
 661                 if (out_len < sizeof(out_env))
 662                         copy = min_t(u32, sizeof(out_env) - out_len, out_size);
 663                 else
 664                         copy = 0;
 665                 if (copy && copy_from_user(&out_env[out_len],
 666                                         p + in_len + out_len, copy))
 667                         return -EFAULT;
 668                 out_len += out_size;
 669         }
 670
 671         buf_len = out_len + in_len;
 672         if (buf_len > ND_IOCTL_MAX_BUFLEN) {
 673                 dev_dbg(dev, "%s:%s cmd: %s buf_len: %zu > %d\n", __func__,
 674                                 dimm_name, cmd_name, buf_len,
 675                                 ND_IOCTL_MAX_BUFLEN);
 676                 return -EINVAL;
 677         }
 678
 679         buf = vmalloc(buf_len);
 680         if (!buf)
 681                 return -ENOMEM;
 682
 683         if (copy_from_user(buf, p, buf_len)) {
 684                 rc = -EFAULT;
 685                 goto out;
 686         }
 687
 688         nvdimm_bus_lock(&nvdimm_bus->dev);
 689         rc = nd_cmd_clear_to_send(nvdimm_bus, nvdimm, cmd);
 690         if (rc)
 691                 goto out_unlock;
 692
 693         rc = nd_desc->ndctl(nd_desc, nvdimm, cmd, buf, buf_len, NULL);
 694         if (rc < 0)
 695                 goto out_unlock;
 696         if (copy_to_user(p, buf, buf_len))
 697                 rc = -EFAULT;
 698  out_unlock:
 699         nvdimm_bus_unlock(&nvdimm_bus->dev);
 700  out:
 701         vfree(buf);
 702         return rc;
 703 }
 704
 705 static long nd_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 706 {
 707         long id = (long) file->private_data;
 708         int rc = -ENXIO, ro;
 709         struct nvdimm_bus *nvdimm_bus;
 710
 711         ro = ((file->f_flags & O_ACCMODE) == O_RDONLY);
 712         mutex_lock(&nvdimm_bus_list_mutex);
 713         list_for_each_entry(nvdimm_bus, &nvdimm_bus_list, list) {
 714                 if (nvdimm_bus->id == id) {
 715                         rc = __nd_ioctl(nvdimm_bus, NULL, ro, cmd, arg);
 716                         break;
 717                 }
 718         }
 719         mutex_unlock(&nvdimm_bus_list_mutex);
 720
 721         return rc;
 722 }
 723
 724 static int match_dimm(struct device *dev, void *data)
 725 {
 726         long id = (long) data;
 727
 728         if (is_nvdimm(dev)) {
 729                 struct nvdimm *nvdimm = to_nvdimm(dev);
 730
 731                 return nvdimm->id == id;
 732         }
 733
 734         return 0;
 735 }
 736
 737 static long nvdimm_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 738 {
 739         int rc = -ENXIO, ro;
 740         struct nvdimm_bus *nvdimm_bus;
 741
 742         ro = ((file->f_flags & O_ACCMODE) == O_RDONLY);
 743         mutex_lock(&nvdimm_bus_list_mutex);
 744         list_for_each_entry(nvdimm_bus, &nvdimm_bus_list, list) {
 745                 struct device *dev = device_find_child(&nvdimm_bus->dev,
 746                                 file->private_data, match_dimm);
 747                 struct nvdimm *nvdimm;
 748
 749                 if (!dev)
 750                         continue;
 751
 752                 nvdimm = to_nvdimm(dev);
 753                 rc = __nd_ioctl(nvdimm_bus, nvdimm, ro, cmd, arg);
 754                 put_device(dev);
 755                 break;
 756         }
 757         mutex_unlock(&nvdimm_bus_list_mutex);
 758
 759         return rc;
 760 }
 761
 762 static int nd_open(struct inode *inode, struct file *file)
 763 {
 764         long minor = iminor(inode);
 765
 766         file->private_data = (void *) minor;
 767         return 0;
 768 }
 769
 770 static const struct file_operations nvdimm_bus_fops = {
 771         .owner = THIS_MODULE,
 772         .open = nd_open,
 773         .unlocked_ioctl = nd_ioctl,
 774         .compat_ioctl = nd_ioctl,
 775         .llseek = noop_llseek,
 776 };
 777
 778 static const struct file_operations nvdimm_fops = {
 779         .owner = THIS_MODULE,
 780         .open = nd_open,
 781         .unlocked_ioctl = nvdimm_ioctl,
 782         .compat_ioctl = nvdimm_ioctl,
 783         .llseek = noop_llseek,
 784 };
 785
 786 int __init nvdimm_bus_init(void)
 787 {
 788         int rc;
 789
 790         BUILD_BUG_ON(sizeof(struct nd_smart_payload) != 128);
 791         BUILD_BUG_ON(sizeof(struct nd_smart_threshold_payload) != 8);
 792
 793         rc = bus_register(&nvdimm_bus_type);
 794         if (rc)
 795                 return rc;
 796
 797         rc = register_chrdev(0, "ndctl", &nvdimm_bus_fops);
 798         if (rc < 0)
 799                 goto err_bus_chrdev;
 800         nvdimm_bus_major = rc;
 801
 802         rc = register_chrdev(0, "dimmctl", &nvdimm_fops);
 803         if (rc < 0)
 804                 goto err_dimm_chrdev;
 805         nvdimm_major = rc;
 806
 807         nd_class = class_create(THIS_MODULE, "nd");
 808         if (IS_ERR(nd_class)) {
 809                 rc = PTR_ERR(nd_class);
 810                 goto err_class;
 811         }
 812
 813         return 0;
 814
 815  err_class:
 816         unregister_chrdev(nvdimm_major, "dimmctl");
 817  err_dimm_chrdev:
 818         unregister_chrdev(nvdimm_bus_major, "ndctl");
 819  err_bus_chrdev:
 820         bus_unregister(&nvdimm_bus_type);
 821
 822         return rc;
 823 }
 824
 825 void nvdimm_bus_exit(void)
 826 {
 827         class_destroy(nd_class);
 828         unregister_chrdev(nvdimm_bus_major, "ndctl");
 829         unregister_chrdev(nvdimm_major, "dimmctl");
 830         bus_unregister(&nvdimm_bus_type);
 831 }