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 static DEFINE_IDA(nd_ida);
  35
  36 static int to_nd_device_type(struct device *dev)
  37 {
  38         if (is_nvdimm(dev))
  39                 return ND_DEVICE_DIMM;
  40         else if (is_nd_pmem(dev))
  41                 return ND_DEVICE_REGION_PMEM;
  42         else if (is_nd_blk(dev))
  43                 return ND_DEVICE_REGION_BLK;
  44         else if (is_nd_dax(dev))
  45                 return ND_DEVICE_DAX_PMEM;
  46         else if (is_nd_pmem(dev->parent) || is_nd_blk(dev->parent))
  47                 return nd_region_to_nstype(to_nd_region(dev->parent));
  48
  49         return 0;
  50 }
  51
  52 static int nvdimm_bus_uevent(struct device *dev, struct kobj_uevent_env *env)
  53 {
  54         /*
  55          * Ensure that region devices always have their numa node set as
  56          * early as possible.
  57          */
  58         if (is_nd_pmem(dev) || is_nd_blk(dev))
  59                 set_dev_node(dev, to_nd_region(dev)->numa_node);
  60         return add_uevent_var(env, "MODALIAS=" ND_DEVICE_MODALIAS_FMT,
  61                         to_nd_device_type(dev));
  62 }
  63
  64 static struct module *to_bus_provider(struct device *dev)
  65 {
  66         /* pin bus providers while regions are enabled */
  67         if (is_nd_pmem(dev) || is_nd_blk(dev)) {
  68                 struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
  69
  70                 return nvdimm_bus->nd_desc->module;
  71         }
  72         return NULL;
  73 }
  74
  75 static void nvdimm_bus_probe_start(struct nvdimm_bus *nvdimm_bus)
  76 {
  77         nvdimm_bus_lock(&nvdimm_bus->dev);
  78         nvdimm_bus->probe_active++;
  79         nvdimm_bus_unlock(&nvdimm_bus->dev);
  80 }
  81
  82 static void nvdimm_bus_probe_end(struct nvdimm_bus *nvdimm_bus)
  83 {
  84         nvdimm_bus_lock(&nvdimm_bus->dev);
  85         if (--nvdimm_bus->probe_active == 0)
  86                 wake_up(&nvdimm_bus->probe_wait);
  87         nvdimm_bus_unlock(&nvdimm_bus->dev);
  88 }
  89
  90 static int nvdimm_bus_probe(struct device *dev)
  91 {
  92         struct nd_device_driver *nd_drv = to_nd_device_driver(dev->driver);
  93         struct module *provider = to_bus_provider(dev);
  94         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
  95         int rc;
  96
  97         if (!try_module_get(provider))
  98                 return -ENXIO;
  99
 100         nvdimm_bus_probe_start(nvdimm_bus);
 101         rc = nd_drv->probe(dev);
 102         if (rc == 0)
 103                 nd_region_probe_success(nvdimm_bus, dev);
 104         else
 105                 nd_region_disable(nvdimm_bus, dev);
 106         nvdimm_bus_probe_end(nvdimm_bus);
 107
 108         dev_dbg(&nvdimm_bus->dev, "%s.probe(%s) = %d\n", dev->driver->name,
 109                         dev_name(dev), rc);
 110
 111         if (rc != 0)
 112                 module_put(provider);
 113         return rc;
 114 }
 115
 116 static int nvdimm_bus_remove(struct device *dev)
 117 {
 118         struct nd_device_driver *nd_drv = to_nd_device_driver(dev->driver);
 119         struct module *provider = to_bus_provider(dev);
 120         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
 121         int rc = 0;
 122
 123         if (nd_drv->remove)
 124                 rc = nd_drv->remove(dev);
 125         nd_region_disable(nvdimm_bus, dev);
 126
 127         dev_dbg(&nvdimm_bus->dev, "%s.remove(%s) = %d\n", dev->driver->name,
 128                         dev_name(dev), rc);
 129         module_put(provider);
 130         return rc;
 131 }
 132
 133 static void nvdimm_bus_shutdown(struct device *dev)
 134 {
 135         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
 136         struct nd_device_driver *nd_drv = NULL;
 137
 138         if (dev->driver)
 139                 nd_drv = to_nd_device_driver(dev->driver);
 140
 141         if (nd_drv && nd_drv->shutdown) {
 142                 nd_drv->shutdown(dev);
 143                 dev_dbg(&nvdimm_bus->dev, "%s.shutdown(%s)\n",
 144                                 dev->driver->name, dev_name(dev));
 145         }
 146 }
 147
 148 void nd_device_notify(struct device *dev, enum nvdimm_event event)
 149 {
 150         device_lock(dev);
 151         if (dev->driver) {
 152                 struct nd_device_driver *nd_drv;
 153
 154                 nd_drv = to_nd_device_driver(dev->driver);
 155                 if (nd_drv->notify)
 156                         nd_drv->notify(dev, event);
 157         }
 158         device_unlock(dev);
 159 }
 160 EXPORT_SYMBOL(nd_device_notify);
 161
 162 void nvdimm_region_notify(struct nd_region *nd_region, enum nvdimm_event event)
 163 {
 164         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(&nd_region->dev);
 165
 166         if (!nvdimm_bus)
 167                 return;
 168
 169         /* caller is responsible for holding a reference on the device */
 170         nd_device_notify(&nd_region->dev, event);
 171 }
 172 EXPORT_SYMBOL_GPL(nvdimm_region_notify);
 173
 174 long nvdimm_clear_poison(struct device *dev, phys_addr_t phys,
 175                 unsigned int len)
 176 {
 177         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
 178         struct nvdimm_bus_descriptor *nd_desc;
 179         struct nd_cmd_clear_error clear_err;
 180         struct nd_cmd_ars_cap ars_cap;
 181         u32 clear_err_unit, mask;
 182         int cmd_rc, rc;
 183
 184         if (!nvdimm_bus)
 185                 return -ENXIO;
 186
 187         nd_desc = nvdimm_bus->nd_desc;
 188         /*
 189          * if ndctl does not exist, it's PMEM_LEGACY and
 190          * we want to just pretend everything is handled.
 191          */
 192         if (!nd_desc->ndctl)
 193                 return len;
 194
 195         memset(&ars_cap, 0, sizeof(ars_cap));
 196         ars_cap.address = phys;
 197         ars_cap.length = len;
 198         rc = nd_desc->ndctl(nd_desc, NULL, ND_CMD_ARS_CAP, &ars_cap,
 199                         sizeof(ars_cap), &cmd_rc);
 200         if (rc < 0)
 201                 return rc;
 202         if (cmd_rc < 0)
 203                 return cmd_rc;
 204         clear_err_unit = ars_cap.clear_err_unit;
 205         if (!clear_err_unit || !is_power_of_2(clear_err_unit))
 206                 return -ENXIO;
 207
 208         mask = clear_err_unit - 1;
 209         if ((phys | len) & mask)
 210                 return -ENXIO;
 211         memset(&clear_err, 0, sizeof(clear_err));
 212         clear_err.address = phys;
 213         clear_err.length = len;
 214         rc = nd_desc->ndctl(nd_desc, NULL, ND_CMD_CLEAR_ERROR, &clear_err,
 215                         sizeof(clear_err), &cmd_rc);
 216         if (rc < 0)
 217                 return rc;
 218         if (cmd_rc < 0)
 219                 return cmd_rc;
 220
 221         if (clear_err.cleared > 0)
 222                 nvdimm_clear_from_poison_list(nvdimm_bus, phys,
 223                                               clear_err.cleared);
 224
 225         return clear_err.cleared;
 226 }
 227 EXPORT_SYMBOL_GPL(nvdimm_clear_poison);
 228
 229 static int nvdimm_bus_match(struct device *dev, struct device_driver *drv);
 230
 231 static struct bus_type nvdimm_bus_type = {
 232         .name = "nd",
 233         .uevent = nvdimm_bus_uevent,
 234         .match = nvdimm_bus_match,
 235         .probe = nvdimm_bus_probe,
 236         .remove = nvdimm_bus_remove,
 237         .shutdown = nvdimm_bus_shutdown,
 238 };
 239
 240 static void nvdimm_bus_release(struct device *dev)
 241 {
 242         struct nvdimm_bus *nvdimm_bus;
 243
 244         nvdimm_bus = container_of(dev, struct nvdimm_bus, dev);
 245         ida_simple_remove(&nd_ida, nvdimm_bus->id);
 246         kfree(nvdimm_bus);
 247 }
 248
 249 static bool is_nvdimm_bus(struct device *dev)
 250 {
 251         return dev->release == nvdimm_bus_release;
 252 }
 253
 254 struct nvdimm_bus *walk_to_nvdimm_bus(struct device *nd_dev)
 255 {
 256         struct device *dev;
 257
 258         for (dev = nd_dev; dev; dev = dev->parent)
 259                 if (is_nvdimm_bus(dev))
 260                         break;
 261         dev_WARN_ONCE(nd_dev, !dev, "invalid dev, not on nd bus\n");
 262         if (dev)
 263                 return to_nvdimm_bus(dev);
 264         return NULL;
 265 }
 266
 267 struct nvdimm_bus *to_nvdimm_bus(struct device *dev)
 268 {
 269         struct nvdimm_bus *nvdimm_bus;
 270
 271         nvdimm_bus = container_of(dev, struct nvdimm_bus, dev);
 272         WARN_ON(!is_nvdimm_bus(dev));
 273         return nvdimm_bus;
 274 }
 275 EXPORT_SYMBOL_GPL(to_nvdimm_bus);
 276
 277 struct nvdimm_bus *nvdimm_bus_register(struct device *parent,
 278                 struct nvdimm_bus_descriptor *nd_desc)
 279 {
 280         struct nvdimm_bus *nvdimm_bus;
 281         int rc;
 282
 283         nvdimm_bus = kzalloc(sizeof(*nvdimm_bus), GFP_KERNEL);
 284         if (!nvdimm_bus)
 285                 return NULL;
 286         INIT_LIST_HEAD(&nvdimm_bus->list);
 287         INIT_LIST_HEAD(&nvdimm_bus->mapping_list);
 288         INIT_LIST_HEAD(&nvdimm_bus->poison_list);
 289         init_waitqueue_head(&nvdimm_bus->probe_wait);
 290         nvdimm_bus->id = ida_simple_get(&nd_ida, 0, 0, GFP_KERNEL);
 291         mutex_init(&nvdimm_bus->reconfig_mutex);
 292         if (nvdimm_bus->id < 0) {
 293                 kfree(nvdimm_bus);
 294                 return NULL;
 295         }
 296         nvdimm_bus->nd_desc = nd_desc;
 297         nvdimm_bus->dev.parent = parent;
 298         nvdimm_bus->dev.release = nvdimm_bus_release;
 299         nvdimm_bus->dev.groups = nd_desc->attr_groups;
 300         nvdimm_bus->dev.bus = &nvdimm_bus_type;
 301         dev_set_name(&nvdimm_bus->dev, "ndbus%d", nvdimm_bus->id);
 302         rc = device_register(&nvdimm_bus->dev);
 303         if (rc) {
 304                 dev_dbg(&nvdimm_bus->dev, "registration failed: %d\n", rc);
 305                 goto err;
 306         }
 307
 308         return nvdimm_bus;
 309  err:
 310         put_device(&nvdimm_bus->dev);
 311         return NULL;
 312 }
 313 EXPORT_SYMBOL_GPL(nvdimm_bus_register);
 314
 315 void nvdimm_bus_unregister(struct nvdimm_bus *nvdimm_bus)
 316 {
 317         if (!nvdimm_bus)
 318                 return;
 319         device_unregister(&nvdimm_bus->dev);
 320 }
 321 EXPORT_SYMBOL_GPL(nvdimm_bus_unregister);
 322
 323 static int child_unregister(struct device *dev, void *data)
 324 {
 325         /*
 326          * the singular ndctl class device per bus needs to be
 327          * "device_destroy"ed, so skip it here
 328          *
 329          * i.e. remove classless children
 330          */
 331         if (dev->class)
 332                 /* pass */;
 333         else
 334                 nd_device_unregister(dev, ND_SYNC);
 335         return 0;
 336 }
 337
 338 static void free_poison_list(struct list_head *poison_list)
 339 {
 340         struct nd_poison *pl, *next;
 341
 342         list_for_each_entry_safe(pl, next, poison_list, list) {
 343                 list_del(&pl->list);
 344                 kfree(pl);
 345         }
 346         list_del_init(poison_list);
 347 }
 348
 349 static int nd_bus_remove(struct device *dev)
 350 {
 351         struct nvdimm_bus *nvdimm_bus = to_nvdimm_bus(dev);
 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
 360         nvdimm_bus_lock(&nvdimm_bus->dev);
 361         free_poison_list(&nvdimm_bus->poison_list);
 362         nvdimm_bus_unlock(&nvdimm_bus->dev);
 363
 364         nvdimm_bus_destroy_ndctl(nvdimm_bus);
 365
 366         return 0;
 367 }
 368
 369 static int nd_bus_probe(struct device *dev)
 370 {
 371         struct nvdimm_bus *nvdimm_bus = to_nvdimm_bus(dev);
 372         int rc;
 373
 374         rc = nvdimm_bus_create_ndctl(nvdimm_bus);
 375         if (rc)
 376                 return rc;
 377
 378         mutex_lock(&nvdimm_bus_list_mutex);
 379         list_add_tail(&nvdimm_bus->list, &nvdimm_bus_list);
 380         mutex_unlock(&nvdimm_bus_list_mutex);
 381
 382         /* enable bus provider attributes to look up their local context */
 383         dev_set_drvdata(dev, nvdimm_bus->nd_desc);
 384
 385         return 0;
 386 }
 387
 388 static struct nd_device_driver nd_bus_driver = {
 389         .probe = nd_bus_probe,
 390         .remove = nd_bus_remove,
 391         .drv = {
 392                 .name = "nd_bus",
 393                 .suppress_bind_attrs = true,
 394                 .bus = &nvdimm_bus_type,
 395                 .owner = THIS_MODULE,
 396                 .mod_name = KBUILD_MODNAME,
 397         },
 398 };
 399
 400 static int nvdimm_bus_match(struct device *dev, struct device_driver *drv)
 401 {
 402         struct nd_device_driver *nd_drv = to_nd_device_driver(drv);
 403
 404         if (is_nvdimm_bus(dev) && nd_drv == &nd_bus_driver)
 405                 return true;
 406
 407         return !!test_bit(to_nd_device_type(dev), &nd_drv->type);
 408 }
 409
 410 static ASYNC_DOMAIN_EXCLUSIVE(nd_async_domain);
 411
 412 void nd_synchronize(void)
 413 {
 414         async_synchronize_full_domain(&nd_async_domain);
 415 }
 416 EXPORT_SYMBOL_GPL(nd_synchronize);
 417
 418 static void nd_async_device_register(void *d, async_cookie_t cookie)
 419 {
 420         struct device *dev = d;
 421
 422         if (device_add(dev) != 0) {
 423                 dev_err(dev, "%s: failed\n", __func__);
 424                 put_device(dev);
 425         }
 426         put_device(dev);
 427         if (dev->parent)
 428                 put_device(dev->parent);
 429 }
 430
 431 static void nd_async_device_unregister(void *d, async_cookie_t cookie)
 432 {
 433         struct device *dev = d;
 434
 435         /* flush bus operations before delete */
 436         nvdimm_bus_lock(dev);
 437         nvdimm_bus_unlock(dev);
 438
 439         device_unregister(dev);
 440         put_device(dev);
 441 }
 442
 443 void __nd_device_register(struct device *dev)
 444 {
 445         if (!dev)
 446                 return;
 447         dev->bus = &nvdimm_bus_type;
 448         if (dev->parent)
 449                 get_device(dev->parent);
 450         get_device(dev);
 451         async_schedule_domain(nd_async_device_register, dev,
 452                         &nd_async_domain);
 453 }
 454
 455 void nd_device_register(struct device *dev)
 456 {
 457         device_initialize(dev);
 458         __nd_device_register(dev);
 459 }
 460 EXPORT_SYMBOL(nd_device_register);
 461
 462 void nd_device_unregister(struct device *dev, enum nd_async_mode mode)
 463 {
 464         switch (mode) {
 465         case ND_ASYNC:
 466                 get_device(dev);
 467                 async_schedule_domain(nd_async_device_unregister, dev,
 468                                 &nd_async_domain);
 469                 break;
 470         case ND_SYNC:
 471                 nd_synchronize();
 472                 device_unregister(dev);
 473                 break;
 474         }
 475 }
 476 EXPORT_SYMBOL(nd_device_unregister);
 477
 478 /**
 479  * __nd_driver_register() - register a region or a namespace driver
 480  * @nd_drv: driver to register
 481  * @owner: automatically set by nd_driver_register() macro
 482  * @mod_name: automatically set by nd_driver_register() macro
 483  */
 484 int __nd_driver_register(struct nd_device_driver *nd_drv, struct module *owner,
 485                 const char *mod_name)
 486 {
 487         struct device_driver *drv = &nd_drv->drv;
 488
 489         if (!nd_drv->type) {
 490                 pr_debug("driver type bitmask not set (%pf)\n",
 491                                 __builtin_return_address(0));
 492                 return -EINVAL;
 493         }
 494
 495         if (!nd_drv->probe) {
 496                 pr_debug("%s ->probe() must be specified\n", mod_name);
 497                 return -EINVAL;
 498         }
 499
 500         drv->bus = &nvdimm_bus_type;
 501         drv->owner = owner;
 502         drv->mod_name = mod_name;
 503
 504         return driver_register(drv);
 505 }
 506 EXPORT_SYMBOL(__nd_driver_register);
 507
 508 int nvdimm_revalidate_disk(struct gendisk *disk)
 509 {
 510         struct device *dev = disk_to_dev(disk)->parent;
 511         struct nd_region *nd_region = to_nd_region(dev->parent);
 512         int disk_ro = get_disk_ro(disk);
 513
 514         /*
 515          * Upgrade to read-only if the region is read-only preserve as
 516          * read-only if the disk is already read-only.
 517          */
 518         if (disk_ro || nd_region->ro == disk_ro)
 519                 return 0;
 520
 521         dev_info(dev, "%s read-only, marking %s read-only\n",
 522                         dev_name(&nd_region->dev), disk->disk_name);
 523         set_disk_ro(disk, 1);
 524
 525         return 0;
 526
 527 }
 528 EXPORT_SYMBOL(nvdimm_revalidate_disk);
 529
 530 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
 531                 char *buf)
 532 {
 533         return sprintf(buf, ND_DEVICE_MODALIAS_FMT "\n",
 534                         to_nd_device_type(dev));
 535 }
 536 static DEVICE_ATTR_RO(modalias);
 537
 538 static ssize_t devtype_show(struct device *dev, struct device_attribute *attr,
 539                 char *buf)
 540 {
 541         return sprintf(buf, "%s\n", dev->type->name);
 542 }
 543 static DEVICE_ATTR_RO(devtype);
 544
 545 static struct attribute *nd_device_attributes[] = {
 546         &dev_attr_modalias.attr,
 547         &dev_attr_devtype.attr,
 548         NULL,
 549 };
 550
 551 /**
 552  * nd_device_attribute_group - generic attributes for all devices on an nd bus
 553  */
 554 struct attribute_group nd_device_attribute_group = {
 555         .attrs = nd_device_attributes,
 556 };
 557 EXPORT_SYMBOL_GPL(nd_device_attribute_group);
 558
 559 static ssize_t numa_node_show(struct device *dev,
 560                 struct device_attribute *attr, char *buf)
 561 {
 562         return sprintf(buf, "%d\n", dev_to_node(dev));
 563 }
 564 static DEVICE_ATTR_RO(numa_node);
 565
 566 static struct attribute *nd_numa_attributes[] = {
 567         &dev_attr_numa_node.attr,
 568         NULL,
 569 };
 570
 571 static umode_t nd_numa_attr_visible(struct kobject *kobj, struct attribute *a,
 572                 int n)
 573 {
 574         if (!IS_ENABLED(CONFIG_NUMA))
 575                 return 0;
 576
 577         return a->mode;
 578 }
 579
 580 /**
 581  * nd_numa_attribute_group - NUMA attributes for all devices on an nd bus
 582  */
 583 struct attribute_group nd_numa_attribute_group = {
 584         .attrs = nd_numa_attributes,
 585         .is_visible = nd_numa_attr_visible,
 586 };
 587 EXPORT_SYMBOL_GPL(nd_numa_attribute_group);
 588
 589 int nvdimm_bus_create_ndctl(struct nvdimm_bus *nvdimm_bus)
 590 {
 591         dev_t devt = MKDEV(nvdimm_bus_major, nvdimm_bus->id);
 592         struct device *dev;
 593
 594         dev = device_create(nd_class, &nvdimm_bus->dev, devt, nvdimm_bus,
 595                         "ndctl%d", nvdimm_bus->id);
 596
 597         if (IS_ERR(dev))
 598                 dev_dbg(&nvdimm_bus->dev, "failed to register ndctl%d: %ld\n",
 599                                 nvdimm_bus->id, PTR_ERR(dev));
 600         return PTR_ERR_OR_ZERO(dev);
 601 }
 602
 603 void nvdimm_bus_destroy_ndctl(struct nvdimm_bus *nvdimm_bus)
 604 {
 605         device_destroy(nd_class, MKDEV(nvdimm_bus_major, nvdimm_bus->id));
 606 }
 607
 608 static const struct nd_cmd_desc __nd_cmd_dimm_descs[] = {
 609         [ND_CMD_IMPLEMENTED] = { },
 610         [ND_CMD_SMART] = {
 611                 .out_num = 2,
 612                 .out_sizes = { 4, 128, },
 613         },
 614         [ND_CMD_SMART_THRESHOLD] = {
 615                 .out_num = 2,
 616                 .out_sizes = { 4, 8, },
 617         },
 618         [ND_CMD_DIMM_FLAGS] = {
 619                 .out_num = 2,
 620                 .out_sizes = { 4, 4 },
 621         },
 622         [ND_CMD_GET_CONFIG_SIZE] = {
 623                 .out_num = 3,
 624                 .out_sizes = { 4, 4, 4, },
 625         },
 626         [ND_CMD_GET_CONFIG_DATA] = {
 627                 .in_num = 2,
 628                 .in_sizes = { 4, 4, },
 629                 .out_num = 2,
 630                 .out_sizes = { 4, UINT_MAX, },
 631         },
 632         [ND_CMD_SET_CONFIG_DATA] = {
 633                 .in_num = 3,
 634                 .in_sizes = { 4, 4, UINT_MAX, },
 635                 .out_num = 1,
 636                 .out_sizes = { 4, },
 637         },
 638         [ND_CMD_VENDOR] = {
 639                 .in_num = 3,
 640                 .in_sizes = { 4, 4, UINT_MAX, },
 641                 .out_num = 3,
 642                 .out_sizes = { 4, 4, UINT_MAX, },
 643         },
 644         [ND_CMD_CALL] = {
 645                 .in_num = 2,
 646                 .in_sizes = { sizeof(struct nd_cmd_pkg), UINT_MAX, },
 647                 .out_num = 1,
 648                 .out_sizes = { UINT_MAX, },
 649         },
 650 };
 651
 652 const struct nd_cmd_desc *nd_cmd_dimm_desc(int cmd)
 653 {
 654         if (cmd < ARRAY_SIZE(__nd_cmd_dimm_descs))
 655                 return &__nd_cmd_dimm_descs[cmd];
 656         return NULL;
 657 }
 658 EXPORT_SYMBOL_GPL(nd_cmd_dimm_desc);
 659
 660 static const struct nd_cmd_desc __nd_cmd_bus_descs[] = {
 661         [ND_CMD_IMPLEMENTED] = { },
 662         [ND_CMD_ARS_CAP] = {
 663                 .in_num = 2,
 664                 .in_sizes = { 8, 8, },
 665                 .out_num = 4,
 666                 .out_sizes = { 4, 4, 4, 4, },
 667         },
 668         [ND_CMD_ARS_START] = {
 669                 .in_num = 5,
 670                 .in_sizes = { 8, 8, 2, 1, 5, },
 671                 .out_num = 2,
 672                 .out_sizes = { 4, 4, },
 673         },
 674         [ND_CMD_ARS_STATUS] = {
 675                 .out_num = 3,
 676                 .out_sizes = { 4, 4, UINT_MAX, },
 677         },
 678         [ND_CMD_CLEAR_ERROR] = {
 679                 .in_num = 2,
 680                 .in_sizes = { 8, 8, },
 681                 .out_num = 3,
 682                 .out_sizes = { 4, 4, 8, },
 683         },
 684         [ND_CMD_CALL] = {
 685                 .in_num = 2,
 686                 .in_sizes = { sizeof(struct nd_cmd_pkg), UINT_MAX, },
 687                 .out_num = 1,
 688                 .out_sizes = { UINT_MAX, },
 689         },
 690 };
 691
 692 const struct nd_cmd_desc *nd_cmd_bus_desc(int cmd)
 693 {
 694         if (cmd < ARRAY_SIZE(__nd_cmd_bus_descs))
 695                 return &__nd_cmd_bus_descs[cmd];
 696         return NULL;
 697 }
 698 EXPORT_SYMBOL_GPL(nd_cmd_bus_desc);
 699
 700 u32 nd_cmd_in_size(struct nvdimm *nvdimm, int cmd,
 701                 const struct nd_cmd_desc *desc, int idx, void *buf)
 702 {
 703         if (idx >= desc->in_num)
 704                 return UINT_MAX;
 705
 706         if (desc->in_sizes[idx] < UINT_MAX)
 707                 return desc->in_sizes[idx];
 708
 709         if (nvdimm && cmd == ND_CMD_SET_CONFIG_DATA && idx == 2) {
 710                 struct nd_cmd_set_config_hdr *hdr = buf;
 711
 712                 return hdr->in_length;
 713         } else if (nvdimm && cmd == ND_CMD_VENDOR && idx == 2) {
 714                 struct nd_cmd_vendor_hdr *hdr = buf;
 715
 716                 return hdr->in_length;
 717         } else if (cmd == ND_CMD_CALL) {
 718                 struct nd_cmd_pkg *pkg = buf;
 719
 720                 return pkg->nd_size_in;
 721         }
 722
 723         return UINT_MAX;
 724 }
 725 EXPORT_SYMBOL_GPL(nd_cmd_in_size);
 726
 727 u32 nd_cmd_out_size(struct nvdimm *nvdimm, int cmd,
 728                 const struct nd_cmd_desc *desc, int idx, const u32 *in_field,
 729                 const u32 *out_field, unsigned long remainder)
 730 {
 731         if (idx >= desc->out_num)
 732                 return UINT_MAX;
 733
 734         if (desc->out_sizes[idx] < UINT_MAX)
 735                 return desc->out_sizes[idx];
 736
 737         if (nvdimm && cmd == ND_CMD_GET_CONFIG_DATA && idx == 1)
 738                 return in_field[1];
 739         else if (nvdimm && cmd == ND_CMD_VENDOR && idx == 2)
 740                 return out_field[1];
 741         else if (!nvdimm && cmd == ND_CMD_ARS_STATUS && idx == 2) {
 742                 /*
 743                  * Per table 9-276 ARS Data in ACPI 6.1, out_field[1] is
 744                  * "Size of Output Buffer in bytes, including this
 745                  * field."
 746                  */
 747                 if (out_field[1] < 4)
 748                         return 0;
 749                 /*
 750                  * ACPI 6.1 is ambiguous if 'status' is included in the
 751                  * output size. If we encounter an output size that
 752                  * overshoots the remainder by 4 bytes, assume it was
 753                  * including 'status'.
 754                  */
 755                 if (out_field[1] - 4 == remainder)
 756                         return remainder;
 757                 return out_field[1] - 8;
 758         } else if (cmd == ND_CMD_CALL) {
 759                 struct nd_cmd_pkg *pkg = (struct nd_cmd_pkg *) in_field;
 760
 761                 return pkg->nd_size_out;
 762         }
 763
 764
 765         return UINT_MAX;
 766 }
 767 EXPORT_SYMBOL_GPL(nd_cmd_out_size);
 768
 769 void wait_nvdimm_bus_probe_idle(struct device *dev)
 770 {
 771         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
 772
 773         do {
 774                 if (nvdimm_bus->probe_active == 0)
 775                         break;
 776                 nvdimm_bus_unlock(&nvdimm_bus->dev);
 777                 wait_event(nvdimm_bus->probe_wait,
 778                                 nvdimm_bus->probe_active == 0);
 779                 nvdimm_bus_lock(&nvdimm_bus->dev);
 780         } while (true);
 781 }
 782
 783 static int pmem_active(struct device *dev, void *data)
 784 {
 785         if (is_nd_pmem(dev) && dev->driver)
 786                 return -EBUSY;
 787         return 0;
 788 }
 789
 790 /* set_config requires an idle interleave set */
 791 static int nd_cmd_clear_to_send(struct nvdimm_bus *nvdimm_bus,
 792                 struct nvdimm *nvdimm, unsigned int cmd)
 793 {
 794         struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
 795
 796         /* ask the bus provider if it would like to block this request */
 797         if (nd_desc->clear_to_send) {
 798                 int rc = nd_desc->clear_to_send(nd_desc, nvdimm, cmd);
 799
 800                 if (rc)
 801                         return rc;
 802         }
 803
 804         /* require clear error to go through the pmem driver */
 805         if (!nvdimm && cmd == ND_CMD_CLEAR_ERROR)
 806                 return device_for_each_child(&nvdimm_bus->dev, NULL,
 807                                 pmem_active);
 808
 809         if (!nvdimm || cmd != ND_CMD_SET_CONFIG_DATA)
 810                 return 0;
 811
 812         /* prevent label manipulation while the kernel owns label updates */
 813         wait_nvdimm_bus_probe_idle(&nvdimm_bus->dev);
 814         if (atomic_read(&nvdimm->busy))
 815                 return -EBUSY;
 816         return 0;
 817 }
 818
 819 static int __nd_ioctl(struct nvdimm_bus *nvdimm_bus, struct nvdimm *nvdimm,
 820                 int read_only, unsigned int ioctl_cmd, unsigned long arg)
 821 {
 822         struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
 823         static char out_env[ND_CMD_MAX_ENVELOPE];
 824         static char in_env[ND_CMD_MAX_ENVELOPE];
 825         const struct nd_cmd_desc *desc = NULL;
 826         unsigned int cmd = _IOC_NR(ioctl_cmd);
 827         void __user *p = (void __user *) arg;
 828         struct device *dev = &nvdimm_bus->dev;
 829         const char *cmd_name, *dimm_name;
 830         u32 in_len = 0, out_len = 0;
 831         unsigned long cmd_mask;
 832         struct nd_cmd_pkg pkg;
 833         u64 buf_len = 0;
 834         void *buf;
 835         int rc, i;
 836
 837         if (nvdimm) {
 838                 desc = nd_cmd_dimm_desc(cmd);
 839                 cmd_name = nvdimm_cmd_name(cmd);
 840                 cmd_mask = nvdimm->cmd_mask;
 841                 dimm_name = dev_name(&nvdimm->dev);
 842         } else {
 843                 desc = nd_cmd_bus_desc(cmd);
 844                 cmd_name = nvdimm_bus_cmd_name(cmd);
 845                 cmd_mask = nd_desc->cmd_mask;
 846                 dimm_name = "bus";
 847         }
 848
 849         if (cmd == ND_CMD_CALL) {
 850                 if (copy_from_user(&pkg, p, sizeof(pkg)))
 851                         return -EFAULT;
 852         }
 853
 854         if (!desc ||
 855             (desc->out_num + desc->in_num == 0) ||
 856             cmd > ND_CMD_CALL ||
 857             !test_bit(cmd, &cmd_mask))
 858                 return -ENOTTY;
 859
 860         /* fail write commands (when read-only) */
 861         if (read_only)
 862                 switch (cmd) {
 863                 case ND_CMD_VENDOR:
 864                 case ND_CMD_SET_CONFIG_DATA:
 865                 case ND_CMD_ARS_START:
 866                 case ND_CMD_CLEAR_ERROR:
 867                 case ND_CMD_CALL:
 868                         dev_dbg(&nvdimm_bus->dev, "'%s' command while read-only.\n",
 869                                         nvdimm ? nvdimm_cmd_name(cmd)
 870                                         : nvdimm_bus_cmd_name(cmd));
 871                         return -EPERM;
 872                 default:
 873                         break;
 874                 }
 875
 876         /* process an input envelope */
 877         for (i = 0; i < desc->in_num; i++) {
 878                 u32 in_size, copy;
 879
 880                 in_size = nd_cmd_in_size(nvdimm, cmd, desc, i, in_env);
 881                 if (in_size == UINT_MAX) {
 882                         dev_err(dev, "%s:%s unknown input size cmd: %s field: %d\n",
 883                                         __func__, dimm_name, cmd_name, i);
 884                         return -ENXIO;
 885                 }
 886                 if (in_len < sizeof(in_env))
 887                         copy = min_t(u32, sizeof(in_env) - in_len, in_size);
 888                 else
 889                         copy = 0;
 890                 if (copy && copy_from_user(&in_env[in_len], p + in_len, copy))
 891                         return -EFAULT;
 892                 in_len += in_size;
 893         }
 894
 895         if (cmd == ND_CMD_CALL) {
 896                 dev_dbg(dev, "%s:%s, idx: %llu, in: %u, out: %u, len %llu\n",
 897                                 __func__, dimm_name, pkg.nd_command,
 898                                 in_len, out_len, buf_len);
 899
 900                 for (i = 0; i < ARRAY_SIZE(pkg.nd_reserved2); i++)
 901                         if (pkg.nd_reserved2[i])
 902                                 return -EINVAL;
 903         }
 904
 905         /* process an output envelope */
 906         for (i = 0; i < desc->out_num; i++) {
 907                 u32 out_size = nd_cmd_out_size(nvdimm, cmd, desc, i,
 908                                 (u32 *) in_env, (u32 *) out_env, 0);
 909                 u32 copy;
 910
 911                 if (out_size == UINT_MAX) {
 912                         dev_dbg(dev, "%s:%s unknown output size cmd: %s field: %d\n",
 913                                         __func__, dimm_name, cmd_name, i);
 914                         return -EFAULT;
 915                 }
 916                 if (out_len < sizeof(out_env))
 917                         copy = min_t(u32, sizeof(out_env) - out_len, out_size);
 918                 else
 919                         copy = 0;
 920                 if (copy && copy_from_user(&out_env[out_len],
 921                                         p + in_len + out_len, copy))
 922                         return -EFAULT;
 923                 out_len += out_size;
 924         }
 925
 926         buf_len = (u64) out_len + (u64) in_len;
 927         if (buf_len > ND_IOCTL_MAX_BUFLEN) {
 928                 dev_dbg(dev, "%s:%s cmd: %s buf_len: %llu > %d\n", __func__,
 929                                 dimm_name, cmd_name, buf_len,
 930                                 ND_IOCTL_MAX_BUFLEN);
 931                 return -EINVAL;
 932         }
 933
 934         buf = vmalloc(buf_len);
 935         if (!buf)
 936                 return -ENOMEM;
 937
 938         if (copy_from_user(buf, p, buf_len)) {
 939                 rc = -EFAULT;
 940                 goto out;
 941         }
 942
 943         nvdimm_bus_lock(&nvdimm_bus->dev);
 944         rc = nd_cmd_clear_to_send(nvdimm_bus, nvdimm, cmd);
 945         if (rc)
 946                 goto out_unlock;
 947
 948         rc = nd_desc->ndctl(nd_desc, nvdimm, cmd, buf, buf_len, NULL);
 949         if (rc < 0)
 950                 goto out_unlock;
 951         nvdimm_bus_unlock(&nvdimm_bus->dev);
 952
 953         if (copy_to_user(p, buf, buf_len))
 954                 rc = -EFAULT;
 955
 956         vfree(buf);
 957         return rc;
 958
 959  out_unlock:
 960         nvdimm_bus_unlock(&nvdimm_bus->dev);
 961  out:
 962         vfree(buf);
 963         return rc;
 964 }
 965
 966 static long nd_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 967 {
 968         long id = (long) file->private_data;
 969         int rc = -ENXIO, ro;
 970         struct nvdimm_bus *nvdimm_bus;
 971
 972         ro = ((file->f_flags & O_ACCMODE) == O_RDONLY);
 973         mutex_lock(&nvdimm_bus_list_mutex);
 974         list_for_each_entry(nvdimm_bus, &nvdimm_bus_list, list) {
 975                 if (nvdimm_bus->id == id) {
 976                         rc = __nd_ioctl(nvdimm_bus, NULL, ro, cmd, arg);
 977                         break;
 978                 }
 979         }
 980         mutex_unlock(&nvdimm_bus_list_mutex);
 981
 982         return rc;
 983 }
 984
 985 static int match_dimm(struct device *dev, void *data)
 986 {
 987         long id = (long) data;
 988
 989         if (is_nvdimm(dev)) {
 990                 struct nvdimm *nvdimm = to_nvdimm(dev);
 991
 992                 return nvdimm->id == id;
 993         }
 994
 995         return 0;
 996 }
 997
 998 static long nvdimm_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 999 {
1000         int rc = -ENXIO, ro;
1001         struct nvdimm_bus *nvdimm_bus;
1002
1003         ro = ((file->f_flags & O_ACCMODE) == O_RDONLY);
1004         mutex_lock(&nvdimm_bus_list_mutex);
1005         list_for_each_entry(nvdimm_bus, &nvdimm_bus_list, list) {
1006                 struct device *dev = device_find_child(&nvdimm_bus->dev,
1007                                 file->private_data, match_dimm);
1008                 struct nvdimm *nvdimm;
1009
1010                 if (!dev)
1011                         continue;
1012
1013                 nvdimm = to_nvdimm(dev);
1014                 rc = __nd_ioctl(nvdimm_bus, nvdimm, ro, cmd, arg);
1015                 put_device(dev);
1016                 break;
1017         }
1018         mutex_unlock(&nvdimm_bus_list_mutex);
1019
1020         return rc;
1021 }
1022
1023 static int nd_open(struct inode *inode, struct file *file)
1024 {
1025         long minor = iminor(inode);
1026
1027         file->private_data = (void *) minor;
1028         return 0;
1029 }
1030
1031 static const struct file_operations nvdimm_bus_fops = {
1032         .owner = THIS_MODULE,
1033         .open = nd_open,
1034         .unlocked_ioctl = nd_ioctl,
1035         .compat_ioctl = nd_ioctl,
1036         .llseek = noop_llseek,
1037 };
1038
1039 static const struct file_operations nvdimm_fops = {
1040         .owner = THIS_MODULE,
1041         .open = nd_open,
1042         .unlocked_ioctl = nvdimm_ioctl,
1043         .compat_ioctl = nvdimm_ioctl,
1044         .llseek = noop_llseek,
1045 };
1046
1047 int __init nvdimm_bus_init(void)
1048 {
1049         int rc;
1050
1051         BUILD_BUG_ON(sizeof(struct nd_smart_payload) != 128);
1052         BUILD_BUG_ON(sizeof(struct nd_smart_threshold_payload) != 8);
1053
1054         rc = bus_register(&nvdimm_bus_type);
1055         if (rc)
1056                 return rc;
1057
1058         rc = register_chrdev(0, "ndctl", &nvdimm_bus_fops);
1059         if (rc < 0)
1060                 goto err_bus_chrdev;
1061         nvdimm_bus_major = rc;
1062
1063         rc = register_chrdev(0, "dimmctl", &nvdimm_fops);
1064         if (rc < 0)
1065                 goto err_dimm_chrdev;
1066         nvdimm_major = rc;
1067
1068         nd_class = class_create(THIS_MODULE, "nd");
1069         if (IS_ERR(nd_class)) {
1070                 rc = PTR_ERR(nd_class);
1071                 goto err_class;
1072         }
1073
1074         rc = driver_register(&nd_bus_driver.drv);
1075         if (rc)
1076                 goto err_nd_bus;
1077
1078         return 0;
1079
1080  err_nd_bus:
1081         class_destroy(nd_class);
1082  err_class:
1083         unregister_chrdev(nvdimm_major, "dimmctl");
1084  err_dimm_chrdev:
1085         unregister_chrdev(nvdimm_bus_major, "ndctl");
1086  err_bus_chrdev:
1087         bus_unregister(&nvdimm_bus_type);
1088
1089         return rc;
1090 }
1091
1092 void nvdimm_bus_exit(void)
1093 {
1094         driver_unregister(&nd_bus_driver.drv);
1095         class_destroy(nd_class);
1096         unregister_chrdev(nvdimm_bus_major, "ndctl");
1097         unregister_chrdev(nvdimm_major, "dimmctl");
1098         bus_unregister(&nvdimm_bus_type);
1099         ida_destroy(&nd_ida);
1100 }