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 = 0;
 128
 129         if (nd_drv->remove)
 130                 rc = nd_drv->remove(dev);
 131         nd_region_disable(nvdimm_bus, dev);
 132
 133         dev_dbg(&nvdimm_bus->dev, "%s.remove(%s) = %d\n", dev->driver->name,
 134                         dev_name(dev), rc);
 135         module_put(provider);
 136         return rc;
 137 }
 138
 139 static void nvdimm_bus_shutdown(struct device *dev)
 140 {
 141         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
 142         struct nd_device_driver *nd_drv = NULL;
 143
 144         if (dev->driver)
 145                 nd_drv = to_nd_device_driver(dev->driver);
 146
 147         if (nd_drv && nd_drv->shutdown) {
 148                 nd_drv->shutdown(dev);
 149                 dev_dbg(&nvdimm_bus->dev, "%s.shutdown(%s)\n",
 150                                 dev->driver->name, dev_name(dev));
 151         }
 152 }
 153
 154 void nd_device_notify(struct device *dev, enum nvdimm_event event)
 155 {
 156         device_lock(dev);
 157         if (dev->driver) {
 158                 struct nd_device_driver *nd_drv;
 159
 160                 nd_drv = to_nd_device_driver(dev->driver);
 161                 if (nd_drv->notify)
 162                         nd_drv->notify(dev, event);
 163         }
 164         device_unlock(dev);
 165 }
 166 EXPORT_SYMBOL(nd_device_notify);
 167
 168 void nvdimm_region_notify(struct nd_region *nd_region, enum nvdimm_event event)
 169 {
 170         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(&nd_region->dev);
 171
 172         if (!nvdimm_bus)
 173                 return;
 174
 175         /* caller is responsible for holding a reference on the device */
 176         nd_device_notify(&nd_region->dev, event);
 177 }
 178 EXPORT_SYMBOL_GPL(nvdimm_region_notify);
 179
 180 long nvdimm_clear_poison(struct device *dev, phys_addr_t phys,
 181                 unsigned int len)
 182 {
 183         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
 184         struct nvdimm_bus_descriptor *nd_desc;
 185         struct nd_cmd_clear_error clear_err;
 186         struct nd_cmd_ars_cap ars_cap;
 187         u32 clear_err_unit, mask;
 188         int cmd_rc, rc;
 189
 190         if (!nvdimm_bus)
 191                 return -ENXIO;
 192
 193         nd_desc = nvdimm_bus->nd_desc;
 194         if (!nd_desc->ndctl)
 195                 return -ENXIO;
 196
 197         memset(&ars_cap, 0, sizeof(ars_cap));
 198         ars_cap.address = phys;
 199         ars_cap.length = len;
 200         rc = nd_desc->ndctl(nd_desc, NULL, ND_CMD_ARS_CAP, &ars_cap,
 201                         sizeof(ars_cap), &cmd_rc);
 202         if (rc < 0)
 203                 return rc;
 204         if (cmd_rc < 0)
 205                 return cmd_rc;
 206         clear_err_unit = ars_cap.clear_err_unit;
 207         if (!clear_err_unit || !is_power_of_2(clear_err_unit))
 208                 return -ENXIO;
 209
 210         mask = clear_err_unit - 1;
 211         if ((phys | len) & mask)
 212                 return -ENXIO;
 213         memset(&clear_err, 0, sizeof(clear_err));
 214         clear_err.address = phys;
 215         clear_err.length = len;
 216         rc = nd_desc->ndctl(nd_desc, NULL, ND_CMD_CLEAR_ERROR, &clear_err,
 217                         sizeof(clear_err), &cmd_rc);
 218         if (rc < 0)
 219                 return rc;
 220         if (cmd_rc < 0)
 221                 return cmd_rc;
 222         return clear_err.cleared;
 223 }
 224 EXPORT_SYMBOL_GPL(nvdimm_clear_poison);
 225
 226 static struct bus_type nvdimm_bus_type = {
 227         .name = "nd",
 228         .uevent = nvdimm_bus_uevent,
 229         .match = nvdimm_bus_match,
 230         .probe = nvdimm_bus_probe,
 231         .remove = nvdimm_bus_remove,
 232         .shutdown = nvdimm_bus_shutdown,
 233 };
 234
 235 static ASYNC_DOMAIN_EXCLUSIVE(nd_async_domain);
 236
 237 void nd_synchronize(void)
 238 {
 239         async_synchronize_full_domain(&nd_async_domain);
 240 }
 241 EXPORT_SYMBOL_GPL(nd_synchronize);
 242
 243 static void nd_async_device_register(void *d, async_cookie_t cookie)
 244 {
 245         struct device *dev = d;
 246
 247         if (device_add(dev) != 0) {
 248                 dev_err(dev, "%s: failed\n", __func__);
 249                 put_device(dev);
 250         }
 251         put_device(dev);
 252 }
 253
 254 static void nd_async_device_unregister(void *d, async_cookie_t cookie)
 255 {
 256         struct device *dev = d;
 257
 258         /* flush bus operations before delete */
 259         nvdimm_bus_lock(dev);
 260         nvdimm_bus_unlock(dev);
 261
 262         device_unregister(dev);
 263         put_device(dev);
 264 }
 265
 266 void __nd_device_register(struct device *dev)
 267 {
 268         if (!dev)
 269                 return;
 270         dev->bus = &nvdimm_bus_type;
 271         get_device(dev);
 272         async_schedule_domain(nd_async_device_register, dev,
 273                         &nd_async_domain);
 274 }
 275
 276 void nd_device_register(struct device *dev)
 277 {
 278         device_initialize(dev);
 279         __nd_device_register(dev);
 280 }
 281 EXPORT_SYMBOL(nd_device_register);
 282
 283 void nd_device_unregister(struct device *dev, enum nd_async_mode mode)
 284 {
 285         switch (mode) {
 286         case ND_ASYNC:
 287                 get_device(dev);
 288                 async_schedule_domain(nd_async_device_unregister, dev,
 289                                 &nd_async_domain);
 290                 break;
 291         case ND_SYNC:
 292                 nd_synchronize();
 293                 device_unregister(dev);
 294                 break;
 295         }
 296 }
 297 EXPORT_SYMBOL(nd_device_unregister);
 298
 299 /**
 300  * __nd_driver_register() - register a region or a namespace driver
 301  * @nd_drv: driver to register
 302  * @owner: automatically set by nd_driver_register() macro
 303  * @mod_name: automatically set by nd_driver_register() macro
 304  */
 305 int __nd_driver_register(struct nd_device_driver *nd_drv, struct module *owner,
 306                 const char *mod_name)
 307 {
 308         struct device_driver *drv = &nd_drv->drv;
 309
 310         if (!nd_drv->type) {
 311                 pr_debug("driver type bitmask not set (%pf)\n",
 312                                 __builtin_return_address(0));
 313                 return -EINVAL;
 314         }
 315
 316         if (!nd_drv->probe) {
 317                 pr_debug("%s ->probe() must be specified\n", mod_name);
 318                 return -EINVAL;
 319         }
 320
 321         drv->bus = &nvdimm_bus_type;
 322         drv->owner = owner;
 323         drv->mod_name = mod_name;
 324
 325         return driver_register(drv);
 326 }
 327 EXPORT_SYMBOL(__nd_driver_register);
 328
 329 int nvdimm_revalidate_disk(struct gendisk *disk)
 330 {
 331         struct device *dev = disk->driverfs_dev;
 332         struct nd_region *nd_region = to_nd_region(dev->parent);
 333         const char *pol = nd_region->ro ? "only" : "write";
 334
 335         if (nd_region->ro == get_disk_ro(disk))
 336                 return 0;
 337
 338         dev_info(dev, "%s read-%s, marking %s read-%s\n",
 339                         dev_name(&nd_region->dev), pol, disk->disk_name, pol);
 340         set_disk_ro(disk, nd_region->ro);
 341
 342         return 0;
 343
 344 }
 345 EXPORT_SYMBOL(nvdimm_revalidate_disk);
 346
 347 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
 348                 char *buf)
 349 {
 350         return sprintf(buf, ND_DEVICE_MODALIAS_FMT "\n",
 351                         to_nd_device_type(dev));
 352 }
 353 static DEVICE_ATTR_RO(modalias);
 354
 355 static ssize_t devtype_show(struct device *dev, struct device_attribute *attr,
 356                 char *buf)
 357 {
 358         return sprintf(buf, "%s\n", dev->type->name);
 359 }
 360 static DEVICE_ATTR_RO(devtype);
 361
 362 static struct attribute *nd_device_attributes[] = {
 363         &dev_attr_modalias.attr,
 364         &dev_attr_devtype.attr,
 365         NULL,
 366 };
 367
 368 /**
 369  * nd_device_attribute_group - generic attributes for all devices on an nd bus
 370  */
 371 struct attribute_group nd_device_attribute_group = {
 372         .attrs = nd_device_attributes,
 373 };
 374 EXPORT_SYMBOL_GPL(nd_device_attribute_group);
 375
 376 static ssize_t numa_node_show(struct device *dev,
 377                 struct device_attribute *attr, char *buf)
 378 {
 379         return sprintf(buf, "%d\n", dev_to_node(dev));
 380 }
 381 static DEVICE_ATTR_RO(numa_node);
 382
 383 static struct attribute *nd_numa_attributes[] = {
 384         &dev_attr_numa_node.attr,
 385         NULL,
 386 };
 387
 388 static umode_t nd_numa_attr_visible(struct kobject *kobj, struct attribute *a,
 389                 int n)
 390 {
 391         if (!IS_ENABLED(CONFIG_NUMA))
 392                 return 0;
 393
 394         return a->mode;
 395 }
 396
 397 /**
 398  * nd_numa_attribute_group - NUMA attributes for all devices on an nd bus
 399  */
 400 struct attribute_group nd_numa_attribute_group = {
 401         .attrs = nd_numa_attributes,
 402         .is_visible = nd_numa_attr_visible,
 403 };
 404 EXPORT_SYMBOL_GPL(nd_numa_attribute_group);
 405
 406 int nvdimm_bus_create_ndctl(struct nvdimm_bus *nvdimm_bus)
 407 {
 408         dev_t devt = MKDEV(nvdimm_bus_major, nvdimm_bus->id);
 409         struct device *dev;
 410
 411         dev = device_create(nd_class, &nvdimm_bus->dev, devt, nvdimm_bus,
 412                         "ndctl%d", nvdimm_bus->id);
 413
 414         if (IS_ERR(dev))
 415                 dev_dbg(&nvdimm_bus->dev, "failed to register ndctl%d: %ld\n",
 416                                 nvdimm_bus->id, PTR_ERR(dev));
 417         return PTR_ERR_OR_ZERO(dev);
 418 }
 419
 420 void nvdimm_bus_destroy_ndctl(struct nvdimm_bus *nvdimm_bus)
 421 {
 422         device_destroy(nd_class, MKDEV(nvdimm_bus_major, nvdimm_bus->id));
 423 }
 424
 425 static const struct nd_cmd_desc __nd_cmd_dimm_descs[] = {
 426         [ND_CMD_IMPLEMENTED] = { },
 427         [ND_CMD_SMART] = {
 428                 .out_num = 2,
 429                 .out_sizes = { 4, 128, },
 430         },
 431         [ND_CMD_SMART_THRESHOLD] = {
 432                 .out_num = 2,
 433                 .out_sizes = { 4, 8, },
 434         },
 435         [ND_CMD_DIMM_FLAGS] = {
 436                 .out_num = 2,
 437                 .out_sizes = { 4, 4 },
 438         },
 439         [ND_CMD_GET_CONFIG_SIZE] = {
 440                 .out_num = 3,
 441                 .out_sizes = { 4, 4, 4, },
 442         },
 443         [ND_CMD_GET_CONFIG_DATA] = {
 444                 .in_num = 2,
 445                 .in_sizes = { 4, 4, },
 446                 .out_num = 2,
 447                 .out_sizes = { 4, UINT_MAX, },
 448         },
 449         [ND_CMD_SET_CONFIG_DATA] = {
 450                 .in_num = 3,
 451                 .in_sizes = { 4, 4, UINT_MAX, },
 452                 .out_num = 1,
 453                 .out_sizes = { 4, },
 454         },
 455         [ND_CMD_VENDOR] = {
 456                 .in_num = 3,
 457                 .in_sizes = { 4, 4, UINT_MAX, },
 458                 .out_num = 3,
 459                 .out_sizes = { 4, 4, UINT_MAX, },
 460         },
 461         [ND_CMD_CALL] = {
 462                 .in_num = 2,
 463                 .in_sizes = { sizeof(struct nd_cmd_pkg), UINT_MAX, },
 464                 .out_num = 1,
 465                 .out_sizes = { UINT_MAX, },
 466         },
 467 };
 468
 469 const struct nd_cmd_desc *nd_cmd_dimm_desc(int cmd)
 470 {
 471         if (cmd < ARRAY_SIZE(__nd_cmd_dimm_descs))
 472                 return &__nd_cmd_dimm_descs[cmd];
 473         return NULL;
 474 }
 475 EXPORT_SYMBOL_GPL(nd_cmd_dimm_desc);
 476
 477 static const struct nd_cmd_desc __nd_cmd_bus_descs[] = {
 478         [ND_CMD_IMPLEMENTED] = { },
 479         [ND_CMD_ARS_CAP] = {
 480                 .in_num = 2,
 481                 .in_sizes = { 8, 8, },
 482                 .out_num = 4,
 483                 .out_sizes = { 4, 4, 4, 4, },
 484         },
 485         [ND_CMD_ARS_START] = {
 486                 .in_num = 5,
 487                 .in_sizes = { 8, 8, 2, 1, 5, },
 488                 .out_num = 2,
 489                 .out_sizes = { 4, 4, },
 490         },
 491         [ND_CMD_ARS_STATUS] = {
 492                 .out_num = 3,
 493                 .out_sizes = { 4, 4, UINT_MAX, },
 494         },
 495         [ND_CMD_CLEAR_ERROR] = {
 496                 .in_num = 2,
 497                 .in_sizes = { 8, 8, },
 498                 .out_num = 3,
 499                 .out_sizes = { 4, 4, 8, },
 500         },
 501         [ND_CMD_CALL] = {
 502                 .in_num = 2,
 503                 .in_sizes = { sizeof(struct nd_cmd_pkg), UINT_MAX, },
 504                 .out_num = 1,
 505                 .out_sizes = { UINT_MAX, },
 506         },
 507 };
 508
 509 const struct nd_cmd_desc *nd_cmd_bus_desc(int cmd)
 510 {
 511         if (cmd < ARRAY_SIZE(__nd_cmd_bus_descs))
 512                 return &__nd_cmd_bus_descs[cmd];
 513         return NULL;
 514 }
 515 EXPORT_SYMBOL_GPL(nd_cmd_bus_desc);
 516
 517 u32 nd_cmd_in_size(struct nvdimm *nvdimm, int cmd,
 518                 const struct nd_cmd_desc *desc, int idx, void *buf)
 519 {
 520         if (idx >= desc->in_num)
 521                 return UINT_MAX;
 522
 523         if (desc->in_sizes[idx] < UINT_MAX)
 524                 return desc->in_sizes[idx];
 525
 526         if (nvdimm && cmd == ND_CMD_SET_CONFIG_DATA && idx == 2) {
 527                 struct nd_cmd_set_config_hdr *hdr = buf;
 528
 529                 return hdr->in_length;
 530         } else if (nvdimm && cmd == ND_CMD_VENDOR && idx == 2) {
 531                 struct nd_cmd_vendor_hdr *hdr = buf;
 532
 533                 return hdr->in_length;
 534         } else if (cmd == ND_CMD_CALL) {
 535                 struct nd_cmd_pkg *pkg = buf;
 536
 537                 return pkg->nd_size_in;
 538         }
 539
 540         return UINT_MAX;
 541 }
 542 EXPORT_SYMBOL_GPL(nd_cmd_in_size);
 543
 544 u32 nd_cmd_out_size(struct nvdimm *nvdimm, int cmd,
 545                 const struct nd_cmd_desc *desc, int idx, const u32 *in_field,
 546                 const u32 *out_field)
 547 {
 548         if (idx >= desc->out_num)
 549                 return UINT_MAX;
 550
 551         if (desc->out_sizes[idx] < UINT_MAX)
 552                 return desc->out_sizes[idx];
 553
 554         if (nvdimm && cmd == ND_CMD_GET_CONFIG_DATA && idx == 1)
 555                 return in_field[1];
 556         else if (nvdimm && cmd == ND_CMD_VENDOR && idx == 2)
 557                 return out_field[1];
 558         else if (!nvdimm && cmd == ND_CMD_ARS_STATUS && idx == 2)
 559                 return out_field[1] - 8;
 560         else if (cmd == ND_CMD_CALL) {
 561                 struct nd_cmd_pkg *pkg = (struct nd_cmd_pkg *) in_field;
 562
 563                 return pkg->nd_size_out;
 564         }
 565
 566
 567         return UINT_MAX;
 568 }
 569 EXPORT_SYMBOL_GPL(nd_cmd_out_size);
 570
 571 void wait_nvdimm_bus_probe_idle(struct device *dev)
 572 {
 573         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
 574
 575         do {
 576                 if (nvdimm_bus->probe_active == 0)
 577                         break;
 578                 nvdimm_bus_unlock(&nvdimm_bus->dev);
 579                 wait_event(nvdimm_bus->probe_wait,
 580                                 nvdimm_bus->probe_active == 0);
 581                 nvdimm_bus_lock(&nvdimm_bus->dev);
 582         } while (true);
 583 }
 584
 585 static int pmem_active(struct device *dev, void *data)
 586 {
 587         if (is_nd_pmem(dev) && dev->driver)
 588                 return -EBUSY;
 589         return 0;
 590 }
 591
 592 /* set_config requires an idle interleave set */
 593 static int nd_cmd_clear_to_send(struct nvdimm_bus *nvdimm_bus,
 594                 struct nvdimm *nvdimm, unsigned int cmd)
 595 {
 596         struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
 597
 598         /* ask the bus provider if it would like to block this request */
 599         if (nd_desc->clear_to_send) {
 600                 int rc = nd_desc->clear_to_send(nd_desc, nvdimm, cmd);
 601
 602                 if (rc)
 603                         return rc;
 604         }
 605
 606         /* require clear error to go through the pmem driver */
 607         if (!nvdimm && cmd == ND_CMD_CLEAR_ERROR)
 608                 return device_for_each_child(&nvdimm_bus->dev, NULL,
 609                                 pmem_active);
 610
 611         if (!nvdimm || cmd != ND_CMD_SET_CONFIG_DATA)
 612                 return 0;
 613
 614         /* prevent label manipulation while the kernel owns label updates */
 615         wait_nvdimm_bus_probe_idle(&nvdimm_bus->dev);
 616         if (atomic_read(&nvdimm->busy))
 617                 return -EBUSY;
 618         return 0;
 619 }
 620
 621 static int __nd_ioctl(struct nvdimm_bus *nvdimm_bus, struct nvdimm *nvdimm,
 622                 int read_only, unsigned int ioctl_cmd, unsigned long arg)
 623 {
 624         struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
 625         size_t buf_len = 0, in_len = 0, out_len = 0;
 626         static char out_env[ND_CMD_MAX_ENVELOPE];
 627         static char in_env[ND_CMD_MAX_ENVELOPE];
 628         const struct nd_cmd_desc *desc = NULL;
 629         unsigned int cmd = _IOC_NR(ioctl_cmd);
 630         void __user *p = (void __user *) arg;
 631         struct device *dev = &nvdimm_bus->dev;
 632         struct nd_cmd_pkg pkg;
 633         const char *cmd_name, *dimm_name;
 634         unsigned long cmd_mask;
 635         void *buf;
 636         int rc, i;
 637
 638         if (nvdimm) {
 639                 desc = nd_cmd_dimm_desc(cmd);
 640                 cmd_name = nvdimm_cmd_name(cmd);
 641                 cmd_mask = nvdimm->cmd_mask;
 642                 dimm_name = dev_name(&nvdimm->dev);
 643         } else {
 644                 desc = nd_cmd_bus_desc(cmd);
 645                 cmd_name = nvdimm_bus_cmd_name(cmd);
 646                 cmd_mask = nd_desc->cmd_mask;
 647                 dimm_name = "bus";
 648         }
 649
 650         if (cmd == ND_CMD_CALL) {
 651                 if (copy_from_user(&pkg, p, sizeof(pkg)))
 652                         return -EFAULT;
 653         }
 654
 655         if (!desc || (desc->out_num + desc->in_num == 0) ||
 656                         !test_bit(cmd, &cmd_mask))
 657                 return -ENOTTY;
 658
 659         /* fail write commands (when read-only) */
 660         if (read_only)
 661                 switch (cmd) {
 662                 case ND_CMD_VENDOR:
 663                 case ND_CMD_SET_CONFIG_DATA:
 664                 case ND_CMD_ARS_START:
 665                 case ND_CMD_CLEAR_ERROR:
 666                 case ND_CMD_CALL:
 667                         dev_dbg(&nvdimm_bus->dev, "'%s' command while read-only.\n",
 668                                         nvdimm ? nvdimm_cmd_name(cmd)
 669                                         : nvdimm_bus_cmd_name(cmd));
 670                         return -EPERM;
 671                 default:
 672                         break;
 673                 }
 674
 675         /* process an input envelope */
 676         for (i = 0; i < desc->in_num; i++) {
 677                 u32 in_size, copy;
 678
 679                 in_size = nd_cmd_in_size(nvdimm, cmd, desc, i, in_env);
 680                 if (in_size == UINT_MAX) {
 681                         dev_err(dev, "%s:%s unknown input size cmd: %s field: %d\n",
 682                                         __func__, dimm_name, cmd_name, i);
 683                         return -ENXIO;
 684                 }
 685                 if (in_len < sizeof(in_env))
 686                         copy = min_t(u32, sizeof(in_env) - in_len, in_size);
 687                 else
 688                         copy = 0;
 689                 if (copy && copy_from_user(&in_env[in_len], p + in_len, copy))
 690                         return -EFAULT;
 691                 in_len += in_size;
 692         }
 693
 694         if (cmd == ND_CMD_CALL) {
 695                 dev_dbg(dev, "%s:%s, idx: %llu, in: %zu, out: %zu, len %zu\n",
 696                                 __func__, dimm_name, pkg.nd_command,
 697                                 in_len, out_len, buf_len);
 698
 699                 for (i = 0; i < ARRAY_SIZE(pkg.nd_reserved2); i++)
 700                         if (pkg.nd_reserved2[i])
 701                                 return -EINVAL;
 702         }
 703
 704         /* process an output envelope */
 705         for (i = 0; i < desc->out_num; i++) {
 706                 u32 out_size = nd_cmd_out_size(nvdimm, cmd, desc, i,
 707                                 (u32 *) in_env, (u32 *) out_env);
 708                 u32 copy;
 709
 710                 if (out_size == UINT_MAX) {
 711                         dev_dbg(dev, "%s:%s unknown output size cmd: %s field: %d\n",
 712                                         __func__, dimm_name, cmd_name, i);
 713                         return -EFAULT;
 714                 }
 715                 if (out_len < sizeof(out_env))
 716                         copy = min_t(u32, sizeof(out_env) - out_len, out_size);
 717                 else
 718                         copy = 0;
 719                 if (copy && copy_from_user(&out_env[out_len],
 720                                         p + in_len + out_len, copy))
 721                         return -EFAULT;
 722                 out_len += out_size;
 723         }
 724
 725         buf_len = out_len + in_len;
 726         if (buf_len > ND_IOCTL_MAX_BUFLEN) {
 727                 dev_dbg(dev, "%s:%s cmd: %s buf_len: %zu > %d\n", __func__,
 728                                 dimm_name, cmd_name, buf_len,
 729                                 ND_IOCTL_MAX_BUFLEN);
 730                 return -EINVAL;
 731         }
 732
 733         buf = vmalloc(buf_len);
 734         if (!buf)
 735                 return -ENOMEM;
 736
 737         if (copy_from_user(buf, p, buf_len)) {
 738                 rc = -EFAULT;
 739                 goto out;
 740         }
 741
 742         nvdimm_bus_lock(&nvdimm_bus->dev);
 743         rc = nd_cmd_clear_to_send(nvdimm_bus, nvdimm, cmd);
 744         if (rc)
 745                 goto out_unlock;
 746
 747         rc = nd_desc->ndctl(nd_desc, nvdimm, cmd, buf, buf_len, NULL);
 748         if (rc < 0)
 749                 goto out_unlock;
 750         if (copy_to_user(p, buf, buf_len))
 751                 rc = -EFAULT;
 752  out_unlock:
 753         nvdimm_bus_unlock(&nvdimm_bus->dev);
 754  out:
 755         vfree(buf);
 756         return rc;
 757 }
 758
 759 static long nd_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 760 {
 761         long id = (long) file->private_data;
 762         int rc = -ENXIO, ro;
 763         struct nvdimm_bus *nvdimm_bus;
 764
 765         ro = ((file->f_flags & O_ACCMODE) == O_RDONLY);
 766         mutex_lock(&nvdimm_bus_list_mutex);
 767         list_for_each_entry(nvdimm_bus, &nvdimm_bus_list, list) {
 768                 if (nvdimm_bus->id == id) {
 769                         rc = __nd_ioctl(nvdimm_bus, NULL, ro, cmd, arg);
 770                         break;
 771                 }
 772         }
 773         mutex_unlock(&nvdimm_bus_list_mutex);
 774
 775         return rc;
 776 }
 777
 778 static int match_dimm(struct device *dev, void *data)
 779 {
 780         long id = (long) data;
 781
 782         if (is_nvdimm(dev)) {
 783                 struct nvdimm *nvdimm = to_nvdimm(dev);
 784
 785                 return nvdimm->id == id;
 786         }
 787
 788         return 0;
 789 }
 790
 791 static long nvdimm_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 792 {
 793         int rc = -ENXIO, ro;
 794         struct nvdimm_bus *nvdimm_bus;
 795
 796         ro = ((file->f_flags & O_ACCMODE) == O_RDONLY);
 797         mutex_lock(&nvdimm_bus_list_mutex);
 798         list_for_each_entry(nvdimm_bus, &nvdimm_bus_list, list) {
 799                 struct device *dev = device_find_child(&nvdimm_bus->dev,
 800                                 file->private_data, match_dimm);
 801                 struct nvdimm *nvdimm;
 802
 803                 if (!dev)
 804                         continue;
 805
 806                 nvdimm = to_nvdimm(dev);
 807                 rc = __nd_ioctl(nvdimm_bus, nvdimm, ro, cmd, arg);
 808                 put_device(dev);
 809                 break;
 810         }
 811         mutex_unlock(&nvdimm_bus_list_mutex);
 812
 813         return rc;
 814 }
 815
 816 static int nd_open(struct inode *inode, struct file *file)
 817 {
 818         long minor = iminor(inode);
 819
 820         file->private_data = (void *) minor;
 821         return 0;
 822 }
 823
 824 static const struct file_operations nvdimm_bus_fops = {
 825         .owner = THIS_MODULE,
 826         .open = nd_open,
 827         .unlocked_ioctl = nd_ioctl,
 828         .compat_ioctl = nd_ioctl,
 829         .llseek = noop_llseek,
 830 };
 831
 832 static const struct file_operations nvdimm_fops = {
 833         .owner = THIS_MODULE,
 834         .open = nd_open,
 835         .unlocked_ioctl = nvdimm_ioctl,
 836         .compat_ioctl = nvdimm_ioctl,
 837         .llseek = noop_llseek,
 838 };
 839
 840 int __init nvdimm_bus_init(void)
 841 {
 842         int rc;
 843
 844         BUILD_BUG_ON(sizeof(struct nd_smart_payload) != 128);
 845         BUILD_BUG_ON(sizeof(struct nd_smart_threshold_payload) != 8);
 846
 847         rc = bus_register(&nvdimm_bus_type);
 848         if (rc)
 849                 return rc;
 850
 851         rc = register_chrdev(0, "ndctl", &nvdimm_bus_fops);
 852         if (rc < 0)
 853                 goto err_bus_chrdev;
 854         nvdimm_bus_major = rc;
 855
 856         rc = register_chrdev(0, "dimmctl", &nvdimm_fops);
 857         if (rc < 0)
 858                 goto err_dimm_chrdev;
 859         nvdimm_major = rc;
 860
 861         nd_class = class_create(THIS_MODULE, "nd");
 862         if (IS_ERR(nd_class)) {
 863                 rc = PTR_ERR(nd_class);
 864                 goto err_class;
 865         }
 866
 867         return 0;
 868
 869  err_class:
 870         unregister_chrdev(nvdimm_major, "dimmctl");
 871  err_dimm_chrdev:
 872         unregister_chrdev(nvdimm_bus_major, "ndctl");
 873  err_bus_chrdev:
 874         bus_unregister(&nvdimm_bus_type);
 875
 876         return rc;
 877 }
 878
 879 void nvdimm_bus_exit(void)
 880 {
 881         class_destroy(nd_class);
 882         unregister_chrdev(nvdimm_bus_major, "ndctl");
 883         unregister_chrdev(nvdimm_major, "dimmctl");
 884         bus_unregister(&nvdimm_bus_type);
 885 }