drivers/gpu/drm/drm_bufs.c

   1 /*
   2  * Legacy: Generic DRM Buffer Management
   3  *
   4  * Copyright 1999, 2000 Precision Insight, Inc., Cedar Park, Texas.
   5  * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
   6  * All Rights Reserved.
   7  *
   8  * Author: Rickard E. (Rik) Faith <faith@valinux.com>
   9  * Author: Gareth Hughes <gareth@valinux.com>
  10  *
  11  * Permission is hereby granted, free of charge, to any person obtaining a
  12  * copy of this software and associated documentation files (the "Software"),
  13  * to deal in the Software without restriction, including without limitation
  14  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  15  * and/or sell copies of the Software, and to permit persons to whom the
  16  * Software is furnished to do so, subject to the following conditions:
  17  *
  18  * The above copyright notice and this permission notice (including the next
  19  * paragraph) shall be included in all copies or substantial portions of the
  20  * Software.
  21  *
  22  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  23  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  24  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  25  * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
  26  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  27  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  28  * OTHER DEALINGS IN THE SOFTWARE.
  29  */
  30
  31 #include <linux/vmalloc.h>
  32 #include <linux/slab.h>
  33 #include <linux/log2.h>
  34 #include <linux/export.h>
  35 #include <asm/shmparam.h>
  36 #include <drm/drmP.h>
  37 #include "drm_legacy.h"
  38
  39 #include <linux/nospec.h>
  40
  41 static struct drm_map_list *drm_find_matching_map(struct drm_device *dev,
  42                                                   struct drm_local_map *map)
  43 {
  44         struct drm_map_list *entry;
  45         list_for_each_entry(entry, &dev->maplist, head) {
  46                 /*
  47                  * Because the kernel-userspace ABI is fixed at a 32-bit offset
  48                  * while PCI resources may live above that, we only compare the
  49                  * lower 32 bits of the map offset for maps of type
  50                  * _DRM_FRAMEBUFFER or _DRM_REGISTERS.
  51                  * It is assumed that if a driver have more than one resource
  52                  * of each type, the lower 32 bits are different.
  53                  */
  54                 if (!entry->map ||
  55                     map->type != entry->map->type ||
  56                     entry->master != dev->master)
  57                         continue;
  58                 switch (map->type) {
  59                 case _DRM_SHM:
  60                         if (map->flags != _DRM_CONTAINS_LOCK)
  61                                 break;
  62                         return entry;
  63                 case _DRM_REGISTERS:
  64                 case _DRM_FRAME_BUFFER:
  65                         if ((entry->map->offset & 0xffffffff) ==
  66                             (map->offset & 0xffffffff))
  67                                 return entry;
  68                 default: /* Make gcc happy */
  69                         ;
  70                 }
  71                 if (entry->map->offset == map->offset)
  72                         return entry;
  73         }
  74
  75         return NULL;
  76 }
  77
  78 static int drm_map_handle(struct drm_device *dev, struct drm_hash_item *hash,
  79                           unsigned long user_token, int hashed_handle, int shm)
  80 {
  81         int use_hashed_handle, shift;
  82         unsigned long add;
  83
  84 #if (BITS_PER_LONG == 64)
  85         use_hashed_handle = ((user_token & 0xFFFFFFFF00000000UL) || hashed_handle);
  86 #elif (BITS_PER_LONG == 32)
  87         use_hashed_handle = hashed_handle;
  88 #else
  89 #error Unsupported long size. Neither 64 nor 32 bits.
  90 #endif
  91
  92         if (!use_hashed_handle) {
  93                 int ret;
  94                 hash->key = user_token >> PAGE_SHIFT;
  95                 ret = drm_ht_insert_item(&dev->map_hash, hash);
  96                 if (ret != -EINVAL)
  97                         return ret;
  98         }
  99
 100         shift = 0;
 101         add = DRM_MAP_HASH_OFFSET >> PAGE_SHIFT;
 102         if (shm && (SHMLBA > PAGE_SIZE)) {
 103                 int bits = ilog2(SHMLBA >> PAGE_SHIFT) + 1;
 104
 105                 /* For shared memory, we have to preserve the SHMLBA
 106                  * bits of the eventual vma->vm_pgoff value during
 107                  * mmap().  Otherwise we run into cache aliasing problems
 108                  * on some platforms.  On these platforms, the pgoff of
 109                  * a mmap() request is used to pick a suitable virtual
 110                  * address for the mmap() region such that it will not
 111                  * cause cache aliasing problems.
 112                  *
 113                  * Therefore, make sure the SHMLBA relevant bits of the
 114                  * hash value we use are equal to those in the original
 115                  * kernel virtual address.
 116                  */
 117                 shift = bits;
 118                 add |= ((user_token >> PAGE_SHIFT) & ((1UL << bits) - 1UL));
 119         }
 120
 121         return drm_ht_just_insert_please(&dev->map_hash, hash,
 122                                          user_token, 32 - PAGE_SHIFT - 3,
 123                                          shift, add);
 124 }
 125
 126 /**
 127  * Core function to create a range of memory available for mapping by a
 128  * non-root process.
 129  *
 130  * Adjusts the memory offset to its absolute value according to the mapping
 131  * type.  Adds the map to the map list drm_device::maplist. Adds MTRR's where
 132  * applicable and if supported by the kernel.
 133  */
 134 static int drm_addmap_core(struct drm_device *dev, resource_size_t offset,
 135                            unsigned int size, enum drm_map_type type,
 136                            enum drm_map_flags flags,
 137                            struct drm_map_list **maplist)
 138 {
 139         struct drm_local_map *map;
 140         struct drm_map_list *list;
 141         drm_dma_handle_t *dmah;
 142         unsigned long user_token;
 143         int ret;
 144
 145         map = kmalloc(sizeof(*map), GFP_KERNEL);
 146         if (!map)
 147                 return -ENOMEM;
 148
 149         map->offset = offset;
 150         map->size = size;
 151         map->flags = flags;
 152         map->type = type;
 153
 154         /* Only allow shared memory to be removable since we only keep enough
 155          * book keeping information about shared memory to allow for removal
 156          * when processes fork.
 157          */
 158         if ((map->flags & _DRM_REMOVABLE) && map->type != _DRM_SHM) {
 159                 kfree(map);
 160                 return -EINVAL;
 161         }
 162         DRM_DEBUG("offset = 0x%08llx, size = 0x%08lx, type = %d\n",
 163                   (unsigned long long)map->offset, map->size, map->type);
 164
 165         /* page-align _DRM_SHM maps. They are allocated here so there is no security
 166          * hole created by that and it works around various broken drivers that use
 167          * a non-aligned quantity to map the SAREA. --BenH
 168          */
 169         if (map->type == _DRM_SHM)
 170                 map->size = PAGE_ALIGN(map->size);
 171
 172         if ((map->offset & (~(resource_size_t)PAGE_MASK)) || (map->size & (~PAGE_MASK))) {
 173                 kfree(map);
 174                 return -EINVAL;
 175         }
 176         map->mtrr = -1;
 177         map->handle = NULL;
 178
 179         switch (map->type) {
 180         case _DRM_REGISTERS:
 181         case _DRM_FRAME_BUFFER:
 182 #if !defined(__sparc__) && !defined(__alpha__) && !defined(__ia64__) && !defined(__powerpc64__) && !defined(__x86_64__) && !defined(__arm__)
 183                 if (map->offset + (map->size-1) < map->offset ||
 184                     map->offset < virt_to_phys(high_memory)) {
 185                         kfree(map);
 186                         return -EINVAL;
 187                 }
 188 #endif
 189                 /* Some drivers preinitialize some maps, without the X Server
 190                  * needing to be aware of it.  Therefore, we just return success
 191                  * when the server tries to create a duplicate map.
 192                  */
 193                 list = drm_find_matching_map(dev, map);
 194                 if (list != NULL) {
 195                         if (list->map->size != map->size) {
 196                                 DRM_DEBUG("Matching maps of type %d with "
 197                                           "mismatched sizes, (%ld vs %ld)\n",
 198                                           map->type, map->size,
 199                                           list->map->size);
 200                                 list->map->size = map->size;
 201                         }
 202
 203                         kfree(map);
 204                         *maplist = list;
 205                         return 0;
 206                 }
 207
 208                 if (map->type == _DRM_FRAME_BUFFER ||
 209                     (map->flags & _DRM_WRITE_COMBINING)) {
 210                         map->mtrr =
 211                                 arch_phys_wc_add(map->offset, map->size);
 212                 }
 213                 if (map->type == _DRM_REGISTERS) {
 214                         if (map->flags & _DRM_WRITE_COMBINING)
 215                                 map->handle = ioremap_wc(map->offset,
 216                                                          map->size);
 217                         else
 218                                 map->handle = ioremap(map->offset, map->size);
 219                         if (!map->handle) {
 220                                 kfree(map);
 221                                 return -ENOMEM;
 222                         }
 223                 }
 224
 225                 break;
 226         case _DRM_SHM:
 227                 list = drm_find_matching_map(dev, map);
 228                 if (list != NULL) {
 229                         if (list->map->size != map->size) {
 230                                 DRM_DEBUG("Matching maps of type %d with "
 231                                           "mismatched sizes, (%ld vs %ld)\n",
 232                                           map->type, map->size, list->map->size);
 233                                 list->map->size = map->size;
 234                         }
 235
 236                         kfree(map);
 237                         *maplist = list;
 238                         return 0;
 239                 }
 240                 map->handle = vmalloc_user(map->size);
 241                 DRM_DEBUG("%lu %d %p\n",
 242                           map->size, order_base_2(map->size), map->handle);
 243                 if (!map->handle) {
 244                         kfree(map);
 245                         return -ENOMEM;
 246                 }
 247                 map->offset = (unsigned long)map->handle;
 248                 if (map->flags & _DRM_CONTAINS_LOCK) {
 249                         /* Prevent a 2nd X Server from creating a 2nd lock */
 250                         if (dev->master->lock.hw_lock != NULL) {
 251                                 vfree(map->handle);
 252                                 kfree(map);
 253                                 return -EBUSY;
 254                         }
 255                         dev->sigdata.lock = dev->master->lock.hw_lock = map->handle;    /* Pointer to lock */
 256                 }
 257                 break;
 258         case _DRM_AGP: {
 259                 struct drm_agp_mem *entry;
 260                 int valid = 0;
 261
 262                 if (!dev->agp) {
 263                         kfree(map);
 264                         return -EINVAL;
 265                 }
 266 #ifdef __alpha__
 267                 map->offset += dev->hose->mem_space->start;
 268 #endif
 269                 /* In some cases (i810 driver), user space may have already
 270                  * added the AGP base itself, because dev->agp->base previously
 271                  * only got set during AGP enable.  So, only add the base
 272                  * address if the map's offset isn't already within the
 273                  * aperture.
 274                  */
 275                 if (map->offset < dev->agp->base ||
 276                     map->offset > dev->agp->base +
 277                     dev->agp->agp_info.aper_size * 1024 * 1024 - 1) {
 278                         map->offset += dev->agp->base;
 279                 }
 280                 map->mtrr = dev->agp->agp_mtrr; /* for getmap */
 281
 282                 /* This assumes the DRM is in total control of AGP space.
 283                  * It's not always the case as AGP can be in the control
 284                  * of user space (i.e. i810 driver). So this loop will get
 285                  * skipped and we double check that dev->agp->memory is
 286                  * actually set as well as being invalid before EPERM'ing
 287                  */
 288                 list_for_each_entry(entry, &dev->agp->memory, head) {
 289                         if ((map->offset >= entry->bound) &&
 290                             (map->offset + map->size <= entry->bound + entry->pages * PAGE_SIZE)) {
 291                                 valid = 1;
 292                                 break;
 293                         }
 294                 }
 295                 if (!list_empty(&dev->agp->memory) && !valid) {
 296                         kfree(map);
 297                         return -EPERM;
 298                 }
 299                 DRM_DEBUG("AGP offset = 0x%08llx, size = 0x%08lx\n",
 300                           (unsigned long long)map->offset, map->size);
 301
 302                 break;
 303         }
 304         case _DRM_SCATTER_GATHER:
 305                 if (!dev->sg) {
 306                         kfree(map);
 307                         return -EINVAL;
 308                 }
 309                 map->offset += (unsigned long)dev->sg->virtual;
 310                 break;
 311         case _DRM_CONSISTENT:
 312                 /* dma_addr_t is 64bit on i386 with CONFIG_HIGHMEM64G,
 313                  * As we're limiting the address to 2^32-1 (or less),
 314                  * casting it down to 32 bits is no problem, but we
 315                  * need to point to a 64bit variable first. */
 316                 dmah = drm_pci_alloc(dev, map->size, map->size);
 317                 if (!dmah) {
 318                         kfree(map);
 319                         return -ENOMEM;
 320                 }
 321                 map->handle = dmah->vaddr;
 322                 map->offset = (unsigned long)dmah->busaddr;
 323                 kfree(dmah);
 324                 break;
 325         default:
 326                 kfree(map);
 327                 return -EINVAL;
 328         }
 329
 330         list = kzalloc(sizeof(*list), GFP_KERNEL);
 331         if (!list) {
 332                 if (map->type == _DRM_REGISTERS)
 333                         iounmap(map->handle);
 334                 kfree(map);
 335                 return -EINVAL;
 336         }
 337         list->map = map;
 338
 339         mutex_lock(&dev->struct_mutex);
 340         list_add(&list->head, &dev->maplist);
 341
 342         /* Assign a 32-bit handle */
 343         /* We do it here so that dev->struct_mutex protects the increment */
 344         user_token = (map->type == _DRM_SHM) ? (unsigned long)map->handle :
 345                 map->offset;
 346         ret = drm_map_handle(dev, &list->hash, user_token, 0,
 347                              (map->type == _DRM_SHM));
 348         if (ret) {
 349                 if (map->type == _DRM_REGISTERS)
 350                         iounmap(map->handle);
 351                 kfree(map);
 352                 kfree(list);
 353                 mutex_unlock(&dev->struct_mutex);
 354                 return ret;
 355         }
 356
 357         list->user_token = list->hash.key << PAGE_SHIFT;
 358         mutex_unlock(&dev->struct_mutex);
 359
 360         if (!(map->flags & _DRM_DRIVER))
 361                 list->master = dev->master;
 362         *maplist = list;
 363         return 0;
 364 }
 365
 366 int drm_legacy_addmap(struct drm_device *dev, resource_size_t offset,
 367                       unsigned int size, enum drm_map_type type,
 368                       enum drm_map_flags flags, struct drm_local_map **map_ptr)
 369 {
 370         struct drm_map_list *list;
 371         int rc;
 372
 373         rc = drm_addmap_core(dev, offset, size, type, flags, &list);
 374         if (!rc)
 375                 *map_ptr = list->map;
 376         return rc;
 377 }
 378 EXPORT_SYMBOL(drm_legacy_addmap);
 379
 380 struct drm_local_map *drm_legacy_findmap(struct drm_device *dev,
 381                                          unsigned int token)
 382 {
 383         struct drm_map_list *_entry;
 384         list_for_each_entry(_entry, &dev->maplist, head)
 385                 if (_entry->user_token == token)
 386                         return _entry->map;
 387         return NULL;
 388 }
 389 EXPORT_SYMBOL(drm_legacy_findmap);
 390
 391 /**
 392  * Ioctl to specify a range of memory that is available for mapping by a
 393  * non-root process.
 394  *
 395  * \param inode device inode.
 396  * \param file_priv DRM file private.
 397  * \param cmd command.
 398  * \param arg pointer to a drm_map structure.
 399  * \return zero on success or a negative value on error.
 400  *
 401  */
 402 int drm_legacy_addmap_ioctl(struct drm_device *dev, void *data,
 403                             struct drm_file *file_priv)
 404 {
 405         struct drm_map *map = data;
 406         struct drm_map_list *maplist;
 407         int err;
 408
 409         if (!(capable(CAP_SYS_ADMIN) || map->type == _DRM_AGP || map->type == _DRM_SHM))
 410                 return -EPERM;
 411
 412         if (!drm_core_check_feature(dev, DRIVER_KMS_LEGACY_CONTEXT) &&
 413             !drm_core_check_feature(dev, DRIVER_LEGACY))
 414                 return -EOPNOTSUPP;
 415
 416         err = drm_addmap_core(dev, map->offset, map->size, map->type,
 417                               map->flags, &maplist);
 418
 419         if (err)
 420                 return err;
 421
 422         /* avoid a warning on 64-bit, this casting isn't very nice, but the API is set so too late */
 423         map->handle = (void *)(unsigned long)maplist->user_token;
 424
 425         /*
 426          * It appears that there are no users of this value whatsoever --
 427          * drmAddMap just discards it.  Let's not encourage its use.
 428          * (Keeping drm_addmap_core's returned mtrr value would be wrong --
 429          *  it's not a real mtrr index anymore.)
 430          */
 431         map->mtrr = -1;
 432
 433         return 0;
 434 }
 435
 436 /*
 437  * Get a mapping information.
 438  *
 439  * \param inode device inode.
 440  * \param file_priv DRM file private.
 441  * \param cmd command.
 442  * \param arg user argument, pointing to a drm_map structure.
 443  *
 444  * \return zero on success or a negative number on failure.
 445  *
 446  * Searches for the mapping with the specified offset and copies its information
 447  * into userspace
 448  */
 449 int drm_legacy_getmap_ioctl(struct drm_device *dev, void *data,
 450                             struct drm_file *file_priv)
 451 {
 452         struct drm_map *map = data;
 453         struct drm_map_list *r_list = NULL;
 454         struct list_head *list;
 455         int idx;
 456         int i;
 457
 458         if (!drm_core_check_feature(dev, DRIVER_KMS_LEGACY_CONTEXT) &&
 459             !drm_core_check_feature(dev, DRIVER_LEGACY))
 460                 return -EOPNOTSUPP;
 461
 462         idx = map->offset;
 463         if (idx < 0)
 464                 return -EINVAL;
 465
 466         i = 0;
 467         mutex_lock(&dev->struct_mutex);
 468         list_for_each(list, &dev->maplist) {
 469                 if (i == idx) {
 470                         r_list = list_entry(list, struct drm_map_list, head);
 471                         break;
 472                 }
 473                 i++;
 474         }
 475         if (!r_list || !r_list->map) {
 476                 mutex_unlock(&dev->struct_mutex);
 477                 return -EINVAL;
 478         }
 479
 480         map->offset = r_list->map->offset;
 481         map->size = r_list->map->size;
 482         map->type = r_list->map->type;
 483         map->flags = r_list->map->flags;
 484         map->handle = (void *)(unsigned long) r_list->user_token;
 485         map->mtrr = arch_phys_wc_index(r_list->map->mtrr);
 486
 487         mutex_unlock(&dev->struct_mutex);
 488
 489         return 0;
 490 }
 491
 492 /**
 493  * Remove a map private from list and deallocate resources if the mapping
 494  * isn't in use.
 495  *
 496  * Searches the map on drm_device::maplist, removes it from the list, see if
 497  * it's being used, and free any associated resource (such as MTRR's) if it's not
 498  * being on use.
 499  *
 500  * \sa drm_legacy_addmap
 501  */
 502 int drm_legacy_rmmap_locked(struct drm_device *dev, struct drm_local_map *map)
 503 {
 504         struct drm_map_list *r_list = NULL, *list_t;
 505         drm_dma_handle_t dmah;
 506         int found = 0;
 507         struct drm_master *master;
 508
 509         /* Find the list entry for the map and remove it */
 510         list_for_each_entry_safe(r_list, list_t, &dev->maplist, head) {
 511                 if (r_list->map == map) {
 512                         master = r_list->master;
 513                         list_del(&r_list->head);
 514                         drm_ht_remove_key(&dev->map_hash,
 515                                           r_list->user_token >> PAGE_SHIFT);
 516                         kfree(r_list);
 517                         found = 1;
 518                         break;
 519                 }
 520         }
 521
 522         if (!found)
 523                 return -EINVAL;
 524
 525         switch (map->type) {
 526         case _DRM_REGISTERS:
 527                 iounmap(map->handle);
 528                 /* FALLTHROUGH */
 529         case _DRM_FRAME_BUFFER:
 530                 arch_phys_wc_del(map->mtrr);
 531                 break;
 532         case _DRM_SHM:
 533                 vfree(map->handle);
 534                 if (master) {
 535                         if (dev->sigdata.lock == master->lock.hw_lock)
 536                                 dev->sigdata.lock = NULL;
 537                         master->lock.hw_lock = NULL;   /* SHM removed */
 538                         master->lock.file_priv = NULL;
 539                         wake_up_interruptible_all(&master->lock.lock_queue);
 540                 }
 541                 break;
 542         case _DRM_AGP:
 543         case _DRM_SCATTER_GATHER:
 544                 break;
 545         case _DRM_CONSISTENT:
 546                 dmah.vaddr = map->handle;
 547                 dmah.busaddr = map->offset;
 548                 dmah.size = map->size;
 549                 __drm_legacy_pci_free(dev, &dmah);
 550                 break;
 551         }
 552         kfree(map);
 553
 554         return 0;
 555 }
 556 EXPORT_SYMBOL(drm_legacy_rmmap_locked);
 557
 558 void drm_legacy_rmmap(struct drm_device *dev, struct drm_local_map *map)
 559 {
 560         if (!drm_core_check_feature(dev, DRIVER_KMS_LEGACY_CONTEXT) &&
 561             !drm_core_check_feature(dev, DRIVER_LEGACY))
 562                 return;
 563
 564         mutex_lock(&dev->struct_mutex);
 565         drm_legacy_rmmap_locked(dev, map);
 566         mutex_unlock(&dev->struct_mutex);
 567 }
 568 EXPORT_SYMBOL(drm_legacy_rmmap);
 569
 570 void drm_legacy_master_rmmaps(struct drm_device *dev, struct drm_master *master)
 571 {
 572         struct drm_map_list *r_list, *list_temp;
 573
 574         if (!drm_core_check_feature(dev, DRIVER_LEGACY))
 575                 return;
 576
 577         mutex_lock(&dev->struct_mutex);
 578         list_for_each_entry_safe(r_list, list_temp, &dev->maplist, head) {
 579                 if (r_list->master == master) {
 580                         drm_legacy_rmmap_locked(dev, r_list->map);
 581                         r_list = NULL;
 582                 }
 583         }
 584         mutex_unlock(&dev->struct_mutex);
 585 }
 586
 587 void drm_legacy_rmmaps(struct drm_device *dev)
 588 {
 589         struct drm_map_list *r_list, *list_temp;
 590
 591         list_for_each_entry_safe(r_list, list_temp, &dev->maplist, head)
 592                 drm_legacy_rmmap(dev, r_list->map);
 593 }
 594
 595 /* The rmmap ioctl appears to be unnecessary.  All mappings are torn down on
 596  * the last close of the device, and this is necessary for cleanup when things
 597  * exit uncleanly.  Therefore, having userland manually remove mappings seems
 598  * like a pointless exercise since they're going away anyway.
 599  *
 600  * One use case might be after addmap is allowed for normal users for SHM and
 601  * gets used by drivers that the server doesn't need to care about.  This seems
 602  * unlikely.
 603  *
 604  * \param inode device inode.
 605  * \param file_priv DRM file private.
 606  * \param cmd command.
 607  * \param arg pointer to a struct drm_map structure.
 608  * \return zero on success or a negative value on error.
 609  */
 610 int drm_legacy_rmmap_ioctl(struct drm_device *dev, void *data,
 611                            struct drm_file *file_priv)
 612 {
 613         struct drm_map *request = data;
 614         struct drm_local_map *map = NULL;
 615         struct drm_map_list *r_list;
 616         int ret;
 617
 618         if (!drm_core_check_feature(dev, DRIVER_KMS_LEGACY_CONTEXT) &&
 619             !drm_core_check_feature(dev, DRIVER_LEGACY))
 620                 return -EOPNOTSUPP;
 621
 622         mutex_lock(&dev->struct_mutex);
 623         list_for_each_entry(r_list, &dev->maplist, head) {
 624                 if (r_list->map &&
 625                     r_list->user_token == (unsigned long)request->handle &&
 626                     r_list->map->flags & _DRM_REMOVABLE) {
 627                         map = r_list->map;
 628                         break;
 629                 }
 630         }
 631
 632         /* List has wrapped around to the head pointer, or it's empty we didn't
 633          * find anything.
 634          */
 635         if (list_empty(&dev->maplist) || !map) {
 636                 mutex_unlock(&dev->struct_mutex);
 637                 return -EINVAL;
 638         }
 639
 640         /* Register and framebuffer maps are permanent */
 641         if ((map->type == _DRM_REGISTERS) || (map->type == _DRM_FRAME_BUFFER)) {
 642                 mutex_unlock(&dev->struct_mutex);
 643                 return 0;
 644         }
 645
 646         ret = drm_legacy_rmmap_locked(dev, map);
 647
 648         mutex_unlock(&dev->struct_mutex);
 649
 650         return ret;
 651 }
 652
 653 /**
 654  * Cleanup after an error on one of the addbufs() functions.
 655  *
 656  * \param dev DRM device.
 657  * \param entry buffer entry where the error occurred.
 658  *
 659  * Frees any pages and buffers associated with the given entry.
 660  */
 661 static void drm_cleanup_buf_error(struct drm_device *dev,
 662                                   struct drm_buf_entry *entry)
 663 {
 664         int i;
 665
 666         if (entry->seg_count) {
 667                 for (i = 0; i < entry->seg_count; i++) {
 668                         if (entry->seglist[i]) {
 669                                 drm_pci_free(dev, entry->seglist[i]);
 670                         }
 671                 }
 672                 kfree(entry->seglist);
 673
 674                 entry->seg_count = 0;
 675         }
 676
 677         if (entry->buf_count) {
 678                 for (i = 0; i < entry->buf_count; i++) {
 679                         kfree(entry->buflist[i].dev_private);
 680                 }
 681                 kfree(entry->buflist);
 682
 683                 entry->buf_count = 0;
 684         }
 685 }
 686
 687 #if IS_ENABLED(CONFIG_AGP)
 688 /**
 689  * Add AGP buffers for DMA transfers.
 690  *
 691  * \param dev struct drm_device to which the buffers are to be added.
 692  * \param request pointer to a struct drm_buf_desc describing the request.
 693  * \return zero on success or a negative number on failure.
 694  *
 695  * After some sanity checks creates a drm_buf structure for each buffer and
 696  * reallocates the buffer list of the same size order to accommodate the new
 697  * buffers.
 698  */
 699 int drm_legacy_addbufs_agp(struct drm_device *dev,
 700                            struct drm_buf_desc *request)
 701 {
 702         struct drm_device_dma *dma = dev->dma;
 703         struct drm_buf_entry *entry;
 704         struct drm_agp_mem *agp_entry;
 705         struct drm_buf *buf;
 706         unsigned long offset;
 707         unsigned long agp_offset;
 708         int count;
 709         int order;
 710         int size;
 711         int alignment;
 712         int page_order;
 713         int total;
 714         int byte_count;
 715         int i, valid;
 716         struct drm_buf **temp_buflist;
 717
 718         if (!dma)
 719                 return -EINVAL;
 720
 721         count = request->count;
 722         order = order_base_2(request->size);
 723         size = 1 << order;
 724
 725         alignment = (request->flags & _DRM_PAGE_ALIGN)
 726             ? PAGE_ALIGN(size) : size;
 727         page_order = order - PAGE_SHIFT > 0 ? order - PAGE_SHIFT : 0;
 728         total = PAGE_SIZE << page_order;
 729
 730         byte_count = 0;
 731         agp_offset = dev->agp->base + request->agp_start;
 732
 733         DRM_DEBUG("count:      %d\n", count);
 734         DRM_DEBUG("order:      %d\n", order);
 735         DRM_DEBUG("size:       %d\n", size);
 736         DRM_DEBUG("agp_offset: %lx\n", agp_offset);
 737         DRM_DEBUG("alignment:  %d\n", alignment);
 738         DRM_DEBUG("page_order: %d\n", page_order);
 739         DRM_DEBUG("total:      %d\n", total);
 740
 741         if (order < DRM_MIN_ORDER || order > DRM_MAX_ORDER)
 742                 return -EINVAL;
 743
 744         /* Make sure buffers are located in AGP memory that we own */
 745         valid = 0;
 746         list_for_each_entry(agp_entry, &dev->agp->memory, head) {
 747                 if ((agp_offset >= agp_entry->bound) &&
 748                     (agp_offset + total * count <= agp_entry->bound + agp_entry->pages * PAGE_SIZE)) {
 749                         valid = 1;
 750                         break;
 751                 }
 752         }
 753         if (!list_empty(&dev->agp->memory) && !valid) {
 754                 DRM_DEBUG("zone invalid\n");
 755                 return -EINVAL;
 756         }
 757         spin_lock(&dev->buf_lock);
 758         if (dev->buf_use) {
 759                 spin_unlock(&dev->buf_lock);
 760                 return -EBUSY;
 761         }
 762         atomic_inc(&dev->buf_alloc);
 763         spin_unlock(&dev->buf_lock);
 764
 765         mutex_lock(&dev->struct_mutex);
 766         entry = &dma->bufs[order];
 767         if (entry->buf_count) {
 768                 mutex_unlock(&dev->struct_mutex);
 769                 atomic_dec(&dev->buf_alloc);
 770                 return -ENOMEM; /* May only call once for each order */
 771         }
 772
 773         if (count < 0 || count > 4096) {
 774                 mutex_unlock(&dev->struct_mutex);
 775                 atomic_dec(&dev->buf_alloc);
 776                 return -EINVAL;
 777         }
 778
 779         entry->buflist = kcalloc(count, sizeof(*entry->buflist), GFP_KERNEL);
 780         if (!entry->buflist) {
 781                 mutex_unlock(&dev->struct_mutex);
 782                 atomic_dec(&dev->buf_alloc);
 783                 return -ENOMEM;
 784         }
 785
 786         entry->buf_size = size;
 787         entry->page_order = page_order;
 788
 789         offset = 0;
 790
 791         while (entry->buf_count < count) {
 792                 buf = &entry->buflist[entry->buf_count];
 793                 buf->idx = dma->buf_count + entry->buf_count;
 794                 buf->total = alignment;
 795                 buf->order = order;
 796                 buf->used = 0;
 797
 798                 buf->offset = (dma->byte_count + offset);
 799                 buf->bus_address = agp_offset + offset;
 800                 buf->address = (void *)(agp_offset + offset);
 801                 buf->next = NULL;
 802                 buf->waiting = 0;
 803                 buf->pending = 0;
 804                 buf->file_priv = NULL;
 805
 806                 buf->dev_priv_size = dev->driver->dev_priv_size;
 807                 buf->dev_private = kzalloc(buf->dev_priv_size, GFP_KERNEL);
 808                 if (!buf->dev_private) {
 809                         /* Set count correctly so we free the proper amount. */
 810                         entry->buf_count = count;
 811                         drm_cleanup_buf_error(dev, entry);
 812                         mutex_unlock(&dev->struct_mutex);
 813                         atomic_dec(&dev->buf_alloc);
 814                         return -ENOMEM;
 815                 }
 816
 817                 DRM_DEBUG("buffer %d @ %p\n", entry->buf_count, buf->address);
 818
 819                 offset += alignment;
 820                 entry->buf_count++;
 821                 byte_count += PAGE_SIZE << page_order;
 822         }
 823
 824         DRM_DEBUG("byte_count: %d\n", byte_count);
 825
 826         temp_buflist = krealloc(dma->buflist,
 827                                 (dma->buf_count + entry->buf_count) *
 828                                 sizeof(*dma->buflist), GFP_KERNEL);
 829         if (!temp_buflist) {
 830                 /* Free the entry because it isn't valid */
 831                 drm_cleanup_buf_error(dev, entry);
 832                 mutex_unlock(&dev->struct_mutex);
 833                 atomic_dec(&dev->buf_alloc);
 834                 return -ENOMEM;
 835         }
 836         dma->buflist = temp_buflist;
 837
 838         for (i = 0; i < entry->buf_count; i++) {
 839                 dma->buflist[i + dma->buf_count] = &entry->buflist[i];
 840         }
 841
 842         dma->buf_count += entry->buf_count;
 843         dma->seg_count += entry->seg_count;
 844         dma->page_count += byte_count >> PAGE_SHIFT;
 845         dma->byte_count += byte_count;
 846
 847         DRM_DEBUG("dma->buf_count : %d\n", dma->buf_count);
 848         DRM_DEBUG("entry->buf_count : %d\n", entry->buf_count);
 849
 850         mutex_unlock(&dev->struct_mutex);
 851
 852         request->count = entry->buf_count;
 853         request->size = size;
 854
 855         dma->flags = _DRM_DMA_USE_AGP;
 856
 857         atomic_dec(&dev->buf_alloc);
 858         return 0;
 859 }
 860 EXPORT_SYMBOL(drm_legacy_addbufs_agp);
 861 #endif /* CONFIG_AGP */
 862
 863 int drm_legacy_addbufs_pci(struct drm_device *dev,
 864                            struct drm_buf_desc *request)
 865 {
 866         struct drm_device_dma *dma = dev->dma;
 867         int count;
 868         int order;
 869         int size;
 870         int total;
 871         int page_order;
 872         struct drm_buf_entry *entry;
 873         drm_dma_handle_t *dmah;
 874         struct drm_buf *buf;
 875         int alignment;
 876         unsigned long offset;
 877         int i;
 878         int byte_count;
 879         int page_count;
 880         unsigned long *temp_pagelist;
 881         struct drm_buf **temp_buflist;
 882
 883         if (!drm_core_check_feature(dev, DRIVER_PCI_DMA))
 884                 return -EOPNOTSUPP;
 885
 886         if (!dma)
 887                 return -EINVAL;
 888
 889         if (!capable(CAP_SYS_ADMIN))
 890                 return -EPERM;
 891
 892         count = request->count;
 893         order = order_base_2(request->size);
 894         size = 1 << order;
 895
 896         DRM_DEBUG("count=%d, size=%d (%d), order=%d\n",
 897                   request->count, request->size, size, order);
 898
 899         if (order < DRM_MIN_ORDER || order > DRM_MAX_ORDER)
 900                 return -EINVAL;
 901
 902         alignment = (request->flags & _DRM_PAGE_ALIGN)
 903             ? PAGE_ALIGN(size) : size;
 904         page_order = order - PAGE_SHIFT > 0 ? order - PAGE_SHIFT : 0;
 905         total = PAGE_SIZE << page_order;
 906
 907         spin_lock(&dev->buf_lock);
 908         if (dev->buf_use) {
 909                 spin_unlock(&dev->buf_lock);
 910                 return -EBUSY;
 911         }
 912         atomic_inc(&dev->buf_alloc);
 913         spin_unlock(&dev->buf_lock);
 914
 915         mutex_lock(&dev->struct_mutex);
 916         entry = &dma->bufs[order];
 917         if (entry->buf_count) {
 918                 mutex_unlock(&dev->struct_mutex);
 919                 atomic_dec(&dev->buf_alloc);
 920                 return -ENOMEM; /* May only call once for each order */
 921         }
 922
 923         if (count < 0 || count > 4096) {
 924                 mutex_unlock(&dev->struct_mutex);
 925                 atomic_dec(&dev->buf_alloc);
 926                 return -EINVAL;
 927         }
 928
 929         entry->buflist = kcalloc(count, sizeof(*entry->buflist), GFP_KERNEL);
 930         if (!entry->buflist) {
 931                 mutex_unlock(&dev->struct_mutex);
 932                 atomic_dec(&dev->buf_alloc);
 933                 return -ENOMEM;
 934         }
 935
 936         entry->seglist = kcalloc(count, sizeof(*entry->seglist), GFP_KERNEL);
 937         if (!entry->seglist) {
 938                 kfree(entry->buflist);
 939                 mutex_unlock(&dev->struct_mutex);
 940                 atomic_dec(&dev->buf_alloc);
 941                 return -ENOMEM;
 942         }
 943
 944         /* Keep the original pagelist until we know all the allocations
 945          * have succeeded
 946          */
 947         temp_pagelist = kmalloc_array(dma->page_count + (count << page_order),
 948                                       sizeof(*dma->pagelist),
 949                                       GFP_KERNEL);
 950         if (!temp_pagelist) {
 951                 kfree(entry->buflist);
 952                 kfree(entry->seglist);
 953                 mutex_unlock(&dev->struct_mutex);
 954                 atomic_dec(&dev->buf_alloc);
 955                 return -ENOMEM;
 956         }
 957         memcpy(temp_pagelist,
 958                dma->pagelist, dma->page_count * sizeof(*dma->pagelist));
 959         DRM_DEBUG("pagelist: %d entries\n",
 960                   dma->page_count + (count << page_order));
 961
 962         entry->buf_size = size;
 963         entry->page_order = page_order;
 964         byte_count = 0;
 965         page_count = 0;
 966
 967         while (entry->buf_count < count) {
 968
 969                 dmah = drm_pci_alloc(dev, PAGE_SIZE << page_order, 0x1000);
 970
 971                 if (!dmah) {
 972                         /* Set count correctly so we free the proper amount. */
 973                         entry->buf_count = count;
 974                         entry->seg_count = count;
 975                         drm_cleanup_buf_error(dev, entry);
 976                         kfree(temp_pagelist);
 977                         mutex_unlock(&dev->struct_mutex);
 978                         atomic_dec(&dev->buf_alloc);
 979                         return -ENOMEM;
 980                 }
 981                 entry->seglist[entry->seg_count++] = dmah;
 982                 for (i = 0; i < (1 << page_order); i++) {
 983                         DRM_DEBUG("page %d @ 0x%08lx\n",
 984                                   dma->page_count + page_count,
 985                                   (unsigned long)dmah->vaddr + PAGE_SIZE * i);
 986                         temp_pagelist[dma->page_count + page_count++]
 987                                 = (unsigned long)dmah->vaddr + PAGE_SIZE * i;
 988                 }
 989                 for (offset = 0;
 990                      offset + size <= total && entry->buf_count < count;
 991                      offset += alignment, ++entry->buf_count) {
 992                         buf = &entry->buflist[entry->buf_count];
 993                         buf->idx = dma->buf_count + entry->buf_count;
 994                         buf->total = alignment;
 995                         buf->order = order;
 996                         buf->used = 0;
 997                         buf->offset = (dma->byte_count + byte_count + offset);
 998                         buf->address = (void *)(dmah->vaddr + offset);
 999                         buf->bus_address = dmah->busaddr + offset;
1000                         buf->next = NULL;
1001                         buf->waiting = 0;
1002                         buf->pending = 0;
1003                         buf->file_priv = NULL;
1004
1005                         buf->dev_priv_size = dev->driver->dev_priv_size;
1006                         buf->dev_private = kzalloc(buf->dev_priv_size,
1007                                                 GFP_KERNEL);
1008                         if (!buf->dev_private) {
1009                                 /* Set count correctly so we free the proper amount. */
1010                                 entry->buf_count = count;
1011                                 entry->seg_count = count;
1012                                 drm_cleanup_buf_error(dev, entry);
1013                                 kfree(temp_pagelist);
1014                                 mutex_unlock(&dev->struct_mutex);
1015                                 atomic_dec(&dev->buf_alloc);
1016                                 return -ENOMEM;
1017                         }
1018
1019                         DRM_DEBUG("buffer %d @ %p\n",
1020                                   entry->buf_count, buf->address);
1021                 }
1022                 byte_count += PAGE_SIZE << page_order;
1023         }
1024
1025         temp_buflist = krealloc(dma->buflist,
1026                                 (dma->buf_count + entry->buf_count) *
1027                                 sizeof(*dma->buflist), GFP_KERNEL);
1028         if (!temp_buflist) {
1029                 /* Free the entry because it isn't valid */
1030                 drm_cleanup_buf_error(dev, entry);
1031                 kfree(temp_pagelist);
1032                 mutex_unlock(&dev->struct_mutex);
1033                 atomic_dec(&dev->buf_alloc);
1034                 return -ENOMEM;
1035         }
1036         dma->buflist = temp_buflist;
1037
1038         for (i = 0; i < entry->buf_count; i++) {
1039                 dma->buflist[i + dma->buf_count] = &entry->buflist[i];
1040         }
1041
1042         /* No allocations failed, so now we can replace the original pagelist
1043          * with the new one.
1044          */
1045         if (dma->page_count) {
1046                 kfree(dma->pagelist);
1047         }
1048         dma->pagelist = temp_pagelist;
1049
1050         dma->buf_count += entry->buf_count;
1051         dma->seg_count += entry->seg_count;
1052         dma->page_count += entry->seg_count << page_order;
1053         dma->byte_count += PAGE_SIZE * (entry->seg_count << page_order);
1054
1055         mutex_unlock(&dev->struct_mutex);
1056
1057         request->count = entry->buf_count;
1058         request->size = size;
1059
1060         if (request->flags & _DRM_PCI_BUFFER_RO)
1061                 dma->flags = _DRM_DMA_USE_PCI_RO;
1062
1063         atomic_dec(&dev->buf_alloc);
1064         return 0;
1065
1066 }
1067 EXPORT_SYMBOL(drm_legacy_addbufs_pci);
1068
1069 static int drm_legacy_addbufs_sg(struct drm_device *dev,
1070                                  struct drm_buf_desc *request)
1071 {
1072         struct drm_device_dma *dma = dev->dma;
1073         struct drm_buf_entry *entry;
1074         struct drm_buf *buf;
1075         unsigned long offset;
1076         unsigned long agp_offset;
1077         int count;
1078         int order;
1079         int size;
1080         int alignment;
1081         int page_order;
1082         int total;
1083         int byte_count;
1084         int i;
1085         struct drm_buf **temp_buflist;
1086
1087         if (!drm_core_check_feature(dev, DRIVER_SG))
1088                 return -EOPNOTSUPP;
1089
1090         if (!dma)
1091                 return -EINVAL;
1092
1093         if (!capable(CAP_SYS_ADMIN))
1094                 return -EPERM;
1095
1096         count = request->count;
1097         order = order_base_2(request->size);
1098         size = 1 << order;
1099
1100         alignment = (request->flags & _DRM_PAGE_ALIGN)
1101             ? PAGE_ALIGN(size) : size;
1102         page_order = order - PAGE_SHIFT > 0 ? order - PAGE_SHIFT : 0;
1103         total = PAGE_SIZE << page_order;
1104
1105         byte_count = 0;
1106         agp_offset = request->agp_start;
1107
1108         DRM_DEBUG("count:      %d\n", count);
1109         DRM_DEBUG("order:      %d\n", order);
1110         DRM_DEBUG("size:       %d\n", size);
1111         DRM_DEBUG("agp_offset: %lu\n", agp_offset);
1112         DRM_DEBUG("alignment:  %d\n", alignment);
1113         DRM_DEBUG("page_order: %d\n", page_order);
1114         DRM_DEBUG("total:      %d\n", total);
1115
1116         if (order < DRM_MIN_ORDER || order > DRM_MAX_ORDER)
1117                 return -EINVAL;
1118
1119         spin_lock(&dev->buf_lock);
1120         if (dev->buf_use) {
1121                 spin_unlock(&dev->buf_lock);
1122                 return -EBUSY;
1123         }
1124         atomic_inc(&dev->buf_alloc);
1125         spin_unlock(&dev->buf_lock);
1126
1127         mutex_lock(&dev->struct_mutex);
1128         entry = &dma->bufs[order];
1129         if (entry->buf_count) {
1130                 mutex_unlock(&dev->struct_mutex);
1131                 atomic_dec(&dev->buf_alloc);
1132                 return -ENOMEM; /* May only call once for each order */
1133         }
1134
1135         if (count < 0 || count > 4096) {
1136                 mutex_unlock(&dev->struct_mutex);
1137                 atomic_dec(&dev->buf_alloc);
1138                 return -EINVAL;
1139         }
1140
1141         entry->buflist = kcalloc(count, sizeof(*entry->buflist), GFP_KERNEL);
1142         if (!entry->buflist) {
1143                 mutex_unlock(&dev->struct_mutex);
1144                 atomic_dec(&dev->buf_alloc);
1145                 return -ENOMEM;
1146         }
1147
1148         entry->buf_size = size;
1149         entry->page_order = page_order;
1150
1151         offset = 0;
1152
1153         while (entry->buf_count < count) {
1154                 buf = &entry->buflist[entry->buf_count];
1155                 buf->idx = dma->buf_count + entry->buf_count;
1156                 buf->total = alignment;
1157                 buf->order = order;
1158                 buf->used = 0;
1159
1160                 buf->offset = (dma->byte_count + offset);
1161                 buf->bus_address = agp_offset + offset;
1162                 buf->address = (void *)(agp_offset + offset
1163                                         + (unsigned long)dev->sg->virtual);
1164                 buf->next = NULL;
1165                 buf->waiting = 0;
1166                 buf->pending = 0;
1167                 buf->file_priv = NULL;
1168
1169                 buf->dev_priv_size = dev->driver->dev_priv_size;
1170                 buf->dev_private = kzalloc(buf->dev_priv_size, GFP_KERNEL);
1171                 if (!buf->dev_private) {
1172                         /* Set count correctly so we free the proper amount. */
1173                         entry->buf_count = count;
1174                         drm_cleanup_buf_error(dev, entry);
1175                         mutex_unlock(&dev->struct_mutex);
1176                         atomic_dec(&dev->buf_alloc);
1177                         return -ENOMEM;
1178                 }
1179
1180                 DRM_DEBUG("buffer %d @ %p\n", entry->buf_count, buf->address);
1181
1182                 offset += alignment;
1183                 entry->buf_count++;
1184                 byte_count += PAGE_SIZE << page_order;
1185         }
1186
1187         DRM_DEBUG("byte_count: %d\n", byte_count);
1188
1189         temp_buflist = krealloc(dma->buflist,
1190                                 (dma->buf_count + entry->buf_count) *
1191                                 sizeof(*dma->buflist), GFP_KERNEL);
1192         if (!temp_buflist) {
1193                 /* Free the entry because it isn't valid */
1194                 drm_cleanup_buf_error(dev, entry);
1195                 mutex_unlock(&dev->struct_mutex);
1196                 atomic_dec(&dev->buf_alloc);
1197                 return -ENOMEM;
1198         }
1199         dma->buflist = temp_buflist;
1200
1201         for (i = 0; i < entry->buf_count; i++) {
1202                 dma->buflist[i + dma->buf_count] = &entry->buflist[i];
1203         }
1204
1205         dma->buf_count += entry->buf_count;
1206         dma->seg_count += entry->seg_count;
1207         dma->page_count += byte_count >> PAGE_SHIFT;
1208         dma->byte_count += byte_count;
1209
1210         DRM_DEBUG("dma->buf_count : %d\n", dma->buf_count);
1211         DRM_DEBUG("entry->buf_count : %d\n", entry->buf_count);
1212
1213         mutex_unlock(&dev->struct_mutex);
1214
1215         request->count = entry->buf_count;
1216         request->size = size;
1217
1218         dma->flags = _DRM_DMA_USE_SG;
1219
1220         atomic_dec(&dev->buf_alloc);
1221         return 0;
1222 }
1223
1224 /**
1225  * Add buffers for DMA transfers (ioctl).
1226  *
1227  * \param inode device inode.
1228  * \param file_priv DRM file private.
1229  * \param cmd command.
1230  * \param arg pointer to a struct drm_buf_desc request.
1231  * \return zero on success or a negative number on failure.
1232  *
1233  * According with the memory type specified in drm_buf_desc::flags and the
1234  * build options, it dispatches the call either to addbufs_agp(),
1235  * addbufs_sg() or addbufs_pci() for AGP, scatter-gather or consistent
1236  * PCI memory respectively.
1237  */
1238 int drm_legacy_addbufs(struct drm_device *dev, void *data,
1239                        struct drm_file *file_priv)
1240 {
1241         struct drm_buf_desc *request = data;
1242         int ret;
1243
1244         if (!drm_core_check_feature(dev, DRIVER_LEGACY))
1245                 return -EOPNOTSUPP;
1246
1247         if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA))
1248                 return -EOPNOTSUPP;
1249
1250 #if IS_ENABLED(CONFIG_AGP)
1251         if (request->flags & _DRM_AGP_BUFFER)
1252                 ret = drm_legacy_addbufs_agp(dev, request);
1253         else
1254 #endif
1255         if (request->flags & _DRM_SG_BUFFER)
1256                 ret = drm_legacy_addbufs_sg(dev, request);
1257         else if (request->flags & _DRM_FB_BUFFER)
1258                 ret = -EINVAL;
1259         else
1260                 ret = drm_legacy_addbufs_pci(dev, request);
1261
1262         return ret;
1263 }
1264
1265 /**
1266  * Get information about the buffer mappings.
1267  *
1268  * This was originally mean for debugging purposes, or by a sophisticated
1269  * client library to determine how best to use the available buffers (e.g.,
1270  * large buffers can be used for image transfer).
1271  *
1272  * \param inode device inode.
1273  * \param file_priv DRM file private.
1274  * \param cmd command.
1275  * \param arg pointer to a drm_buf_info structure.
1276  * \return zero on success or a negative number on failure.
1277  *
1278  * Increments drm_device::buf_use while holding the drm_device::buf_lock
1279  * lock, preventing of allocating more buffers after this call. Information
1280  * about each requested buffer is then copied into user space.
1281  */
1282 int __drm_legacy_infobufs(struct drm_device *dev,
1283                         void *data, int *p,
1284                         int (*f)(void *, int, struct drm_buf_entry *))
1285 {
1286         struct drm_device_dma *dma = dev->dma;
1287         int i;
1288         int count;
1289
1290         if (!drm_core_check_feature(dev, DRIVER_LEGACY))
1291                 return -EOPNOTSUPP;
1292
1293         if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA))
1294                 return -EOPNOTSUPP;
1295
1296         if (!dma)
1297                 return -EINVAL;
1298
1299         spin_lock(&dev->buf_lock);
1300         if (atomic_read(&dev->buf_alloc)) {
1301                 spin_unlock(&dev->buf_lock);
1302                 return -EBUSY;
1303         }
1304         ++dev->buf_use;         /* Can't allocate more after this call */
1305         spin_unlock(&dev->buf_lock);
1306
1307         for (i = 0, count = 0; i < DRM_MAX_ORDER + 1; i++) {
1308                 if (dma->bufs[i].buf_count)
1309                         ++count;
1310         }
1311
1312         DRM_DEBUG("count = %d\n", count);
1313
1314         if (*p >= count) {
1315                 for (i = 0, count = 0; i < DRM_MAX_ORDER + 1; i++) {
1316                         struct drm_buf_entry *from = &dma->bufs[i];
1317                         if (from->buf_count) {
1318                                 if (f(data, count, from) < 0)
1319                                         return -EFAULT;
1320                                 DRM_DEBUG("%d %d %d %d %d\n",
1321                                           i,
1322                                           dma->bufs[i].buf_count,
1323                                           dma->bufs[i].buf_size,
1324                                           dma->bufs[i].low_mark,
1325                                           dma->bufs[i].high_mark);
1326                                 ++count;
1327                         }
1328                 }
1329         }
1330         *p = count;
1331
1332         return 0;
1333 }
1334
1335 static int copy_one_buf(void *data, int count, struct drm_buf_entry *from)
1336 {
1337         struct drm_buf_info *request = data;
1338         struct drm_buf_desc __user *to = &request->list[count];
1339         struct drm_buf_desc v = {.count = from->buf_count,
1340                                  .size = from->buf_size,
1341                                  .low_mark = from->low_mark,
1342                                  .high_mark = from->high_mark};
1343
1344         if (copy_to_user(to, &v, offsetof(struct drm_buf_desc, flags)))
1345                 return -EFAULT;
1346         return 0;
1347 }
1348
1349 int drm_legacy_infobufs(struct drm_device *dev, void *data,
1350                         struct drm_file *file_priv)
1351 {
1352         struct drm_buf_info *request = data;
1353         return __drm_legacy_infobufs(dev, data, &request->count, copy_one_buf);
1354 }
1355
1356 /**
1357  * Specifies a low and high water mark for buffer allocation
1358  *
1359  * \param inode device inode.
1360  * \param file_priv DRM file private.
1361  * \param cmd command.
1362  * \param arg a pointer to a drm_buf_desc structure.
1363  * \return zero on success or a negative number on failure.
1364  *
1365  * Verifies that the size order is bounded between the admissible orders and
1366  * updates the respective drm_device_dma::bufs entry low and high water mark.
1367  *
1368  * \note This ioctl is deprecated and mostly never used.
1369  */
1370 int drm_legacy_markbufs(struct drm_device *dev, void *data,
1371                         struct drm_file *file_priv)
1372 {
1373         struct drm_device_dma *dma = dev->dma;
1374         struct drm_buf_desc *request = data;
1375         int order;
1376         struct drm_buf_entry *entry;
1377
1378         if (!drm_core_check_feature(dev, DRIVER_LEGACY))
1379                 return -EOPNOTSUPP;
1380
1381         if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA))
1382                 return -EOPNOTSUPP;
1383
1384         if (!dma)
1385                 return -EINVAL;
1386
1387         DRM_DEBUG("%d, %d, %d\n",
1388                   request->size, request->low_mark, request->high_mark);
1389         order = order_base_2(request->size);
1390         if (order < DRM_MIN_ORDER || order > DRM_MAX_ORDER)
1391                 return -EINVAL;
1392         entry = &dma->bufs[order];
1393
1394         if (request->low_mark < 0 || request->low_mark > entry->buf_count)
1395                 return -EINVAL;
1396         if (request->high_mark < 0 || request->high_mark > entry->buf_count)
1397                 return -EINVAL;
1398
1399         entry->low_mark = request->low_mark;
1400         entry->high_mark = request->high_mark;
1401
1402         return 0;
1403 }
1404
1405 /**
1406  * Unreserve the buffers in list, previously reserved using drmDMA.
1407  *
1408  * \param inode device inode.
1409  * \param file_priv DRM file private.
1410  * \param cmd command.
1411  * \param arg pointer to a drm_buf_free structure.
1412  * \return zero on success or a negative number on failure.
1413  *
1414  * Calls free_buffer() for each used buffer.
1415  * This function is primarily used for debugging.
1416  */
1417 int drm_legacy_freebufs(struct drm_device *dev, void *data,
1418                         struct drm_file *file_priv)
1419 {
1420         struct drm_device_dma *dma = dev->dma;
1421         struct drm_buf_free *request = data;
1422         int i;
1423         int idx;
1424         struct drm_buf *buf;
1425
1426         if (!drm_core_check_feature(dev, DRIVER_LEGACY))
1427                 return -EOPNOTSUPP;
1428
1429         if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA))
1430                 return -EOPNOTSUPP;
1431
1432         if (!dma)
1433                 return -EINVAL;
1434
1435         DRM_DEBUG("%d\n", request->count);
1436         for (i = 0; i < request->count; i++) {
1437                 if (copy_from_user(&idx, &request->list[i], sizeof(idx)))
1438                         return -EFAULT;
1439                 if (idx < 0 || idx >= dma->buf_count) {
1440                         DRM_ERROR("Index %d (of %d max)\n",
1441                                   idx, dma->buf_count - 1);
1442                         return -EINVAL;
1443                 }
1444                 idx = array_index_nospec(idx, dma->buf_count);
1445                 buf = dma->buflist[idx];
1446                 if (buf->file_priv != file_priv) {
1447                         DRM_ERROR("Process %d freeing buffer not owned\n",
1448                                   task_pid_nr(current));
1449                         return -EINVAL;
1450                 }
1451                 drm_legacy_free_buffer(dev, buf);
1452         }
1453
1454         return 0;
1455 }
1456
1457 /**
1458  * Maps all of the DMA buffers into client-virtual space (ioctl).
1459  *
1460  * \param inode device inode.
1461  * \param file_priv DRM file private.
1462  * \param cmd command.
1463  * \param arg pointer to a drm_buf_map structure.
1464  * \return zero on success or a negative number on failure.
1465  *
1466  * Maps the AGP, SG or PCI buffer region with vm_mmap(), and copies information
1467  * about each buffer into user space. For PCI buffers, it calls vm_mmap() with
1468  * offset equal to 0, which drm_mmap() interpretes as PCI buffers and calls
1469  * drm_mmap_dma().
1470  */
1471 int __drm_legacy_mapbufs(struct drm_device *dev, void *data, int *p,
1472                          void __user **v,
1473                          int (*f)(void *, int, unsigned long,
1474                                  struct drm_buf *),
1475                                  struct drm_file *file_priv)
1476 {
1477         struct drm_device_dma *dma = dev->dma;
1478         int retcode = 0;
1479         unsigned long virtual;
1480         int i;
1481
1482         if (!drm_core_check_feature(dev, DRIVER_LEGACY))
1483                 return -EOPNOTSUPP;
1484
1485         if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA))
1486                 return -EOPNOTSUPP;
1487
1488         if (!dma)
1489                 return -EINVAL;
1490
1491         spin_lock(&dev->buf_lock);
1492         if (atomic_read(&dev->buf_alloc)) {
1493                 spin_unlock(&dev->buf_lock);
1494                 return -EBUSY;
1495         }
1496         dev->buf_use++;         /* Can't allocate more after this call */
1497         spin_unlock(&dev->buf_lock);
1498
1499         if (*p >= dma->buf_count) {
1500                 if ((dev->agp && (dma->flags & _DRM_DMA_USE_AGP))
1501                     || (drm_core_check_feature(dev, DRIVER_SG)
1502                         && (dma->flags & _DRM_DMA_USE_SG))) {
1503                         struct drm_local_map *map = dev->agp_buffer_map;
1504                         unsigned long token = dev->agp_buffer_token;
1505
1506                         if (!map) {
1507                                 retcode = -EINVAL;
1508                                 goto done;
1509                         }
1510                         virtual = vm_mmap(file_priv->filp, 0, map->size,
1511                                           PROT_READ | PROT_WRITE,
1512                                           MAP_SHARED,
1513                                           token);
1514                 } else {
1515                         virtual = vm_mmap(file_priv->filp, 0, dma->byte_count,
1516                                           PROT_READ | PROT_WRITE,
1517                                           MAP_SHARED, 0);
1518                 }
1519                 if (virtual > -1024UL) {
1520                         /* Real error */
1521                         retcode = (signed long)virtual;
1522                         goto done;
1523                 }
1524                 *v = (void __user *)virtual;
1525
1526                 for (i = 0; i < dma->buf_count; i++) {
1527                         if (f(data, i, virtual, dma->buflist[i]) < 0) {
1528                                 retcode = -EFAULT;
1529                                 goto done;
1530                         }
1531                 }
1532         }
1533       done:
1534         *p = dma->buf_count;
1535         DRM_DEBUG("%d buffers, retcode = %d\n", *p, retcode);
1536
1537         return retcode;
1538 }
1539
1540 static int map_one_buf(void *data, int idx, unsigned long virtual,
1541                         struct drm_buf *buf)
1542 {
1543         struct drm_buf_map *request = data;
1544         unsigned long address = virtual + buf->offset;  /* *** */
1545
1546         if (copy_to_user(&request->list[idx].idx, &buf->idx,
1547                          sizeof(request->list[0].idx)))
1548                 return -EFAULT;
1549         if (copy_to_user(&request->list[idx].total, &buf->total,
1550                          sizeof(request->list[0].total)))
1551                 return -EFAULT;
1552         if (clear_user(&request->list[idx].used, sizeof(int)))
1553                 return -EFAULT;
1554         if (copy_to_user(&request->list[idx].address, &address,
1555                          sizeof(address)))
1556                 return -EFAULT;
1557         return 0;
1558 }
1559
1560 int drm_legacy_mapbufs(struct drm_device *dev, void *data,
1561                        struct drm_file *file_priv)
1562 {
1563         struct drm_buf_map *request = data;
1564         return __drm_legacy_mapbufs(dev, data, &request->count,
1565                                     &request->virtual, map_one_buf,
1566                                     file_priv);
1567 }
1568
1569 int drm_legacy_dma_ioctl(struct drm_device *dev, void *data,
1570                   struct drm_file *file_priv)
1571 {
1572         if (!drm_core_check_feature(dev, DRIVER_LEGACY))
1573                 return -EOPNOTSUPP;
1574
1575         if (dev->driver->dma_ioctl)
1576                 return dev->driver->dma_ioctl(dev, data, file_priv);
1577         else
1578                 return -EINVAL;
1579 }
1580
1581 struct drm_local_map *drm_legacy_getsarea(struct drm_device *dev)
1582 {
1583         struct drm_map_list *entry;
1584
1585         list_for_each_entry(entry, &dev->maplist, head) {
1586                 if (entry->map && entry->map->type == _DRM_SHM &&
1587                     (entry->map->flags & _DRM_CONTAINS_LOCK)) {
1588                         return entry->map;
1589                 }
1590         }
1591         return NULL;
1592 }
1593 EXPORT_SYMBOL(drm_legacy_getsarea);