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