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      1 /*	$NetBSD: drm_bufs.c,v 1.16 2021/12/19 12:30:04 riastradh Exp $	*/
      2 
      3 /*
      4  * Legacy: Generic DRM Buffer Management
      5  *
      6  * Copyright 1999, 2000 Precision Insight, Inc., Cedar Park, Texas.
      7  * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
      8  * All Rights Reserved.
      9  *
     10  * Author: Rickard E. (Rik) Faith <faith (at) valinux.com>
     11  * Author: Gareth Hughes <gareth (at) valinux.com>
     12  *
     13  * Permission is hereby granted, free of charge, to any person obtaining a
     14  * copy of this software and associated documentation files (the "Software"),
     15  * to deal in the Software without restriction, including without limitation
     16  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
     17  * and/or sell copies of the Software, and to permit persons to whom the
     18  * Software is furnished to do so, subject to the following conditions:
     19  *
     20  * The above copyright notice and this permission notice (including the next
     21  * paragraph) shall be included in all copies or substantial portions of the
     22  * Software.
     23  *
     24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
     25  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
     26  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
     27  * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
     28  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
     29  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
     30  * OTHER DEALINGS IN THE SOFTWARE.
     31  */
     32 
     33 #include <sys/cdefs.h>
     34 __KERNEL_RCSID(0, "$NetBSD: drm_bufs.c,v 1.16 2021/12/19 12:30:04 riastradh Exp $");
     35 
     36 #include <linux/export.h>
     37 #include <linux/log2.h>
     38 #include <linux/mm.h>
     39 #include <linux/mman.h>
     40 #include <linux/nospec.h>
     41 #include <linux/slab.h>
     42 #include <linux/uaccess.h>
     43 #include <linux/vmalloc.h>
     44 
     45 #include <asm/shmparam.h>
     46 
     47 #include <drm/drm_agpsupport.h>
     48 #include <drm/drm_device.h>
     49 #include <drm/drm_drv.h>
     50 #include <drm/drm_file.h>
     51 #include <drm/drm_pci.h>
     52 #include <drm/drm_print.h>
     53 
     54 #include "drm_legacy.h"
     55 
     56 
     57 static struct drm_map_list *drm_find_matching_map(struct drm_device *dev,
     58 						  struct drm_local_map *map)
     59 {
     60 	struct drm_map_list *entry;
     61 	list_for_each_entry(entry, &dev->maplist, head) {
     62 		/*
     63 		 * Because the kernel-userspace ABI is fixed at a 32-bit offset
     64 		 * while PCI resources may live above that, we only compare the
     65 		 * lower 32 bits of the map offset for maps of type
     66 		 * _DRM_FRAMEBUFFER or _DRM_REGISTERS.
     67 		 * It is assumed that if a driver have more than one resource
     68 		 * of each type, the lower 32 bits are different.
     69 		 */
     70 		if (!entry->map ||
     71 		    map->type != entry->map->type ||
     72 		    entry->master != dev->master)
     73 			continue;
     74 		switch (map->type) {
     75 		case _DRM_SHM:
     76 			if (map->flags != _DRM_CONTAINS_LOCK)
     77 				break;
     78 			return entry;
     79 		case _DRM_REGISTERS:
     80 		case _DRM_FRAME_BUFFER:
     81 			if ((entry->map->offset & 0xffffffff) ==
     82 			    (map->offset & 0xffffffff))
     83 				return entry;
     84 		default: /* Make gcc happy */
     85 			;
     86 		}
     87 		if (entry->map->offset == map->offset)
     88 			return entry;
     89 	}
     90 
     91 	return NULL;
     92 }
     93 
     94 static int drm_map_handle(struct drm_device *dev, struct drm_hash_item *hash,
     95 			  unsigned long user_token, int hashed_handle, int shm)
     96 {
     97 	int use_hashed_handle, shift;
     98 	unsigned long add;
     99 
    100 	use_hashed_handle = (user_token &~ 0xffffffffUL) || hashed_handle;
    101 	if (!use_hashed_handle) {
    102 		int ret;
    103 		hash->key = user_token >> PAGE_SHIFT;
    104 		ret = drm_ht_insert_item(&dev->map_hash, hash);
    105 		if (ret != -EINVAL)
    106 			return ret;
    107 	}
    108 
    109 	shift = 0;
    110 	add = DRM_MAP_HASH_OFFSET >> PAGE_SHIFT;
    111 	if (shm && (SHMLBA > PAGE_SIZE)) {
    112 		int bits = ilog2(SHMLBA >> PAGE_SHIFT) + 1;
    113 
    114 		/* For shared memory, we have to preserve the SHMLBA
    115 		 * bits of the eventual vma->vm_pgoff value during
    116 		 * mmap().  Otherwise we run into cache aliasing problems
    117 		 * on some platforms.  On these platforms, the pgoff of
    118 		 * a mmap() request is used to pick a suitable virtual
    119 		 * address for the mmap() region such that it will not
    120 		 * cause cache aliasing problems.
    121 		 *
    122 		 * Therefore, make sure the SHMLBA relevant bits of the
    123 		 * hash value we use are equal to those in the original
    124 		 * kernel virtual address.
    125 		 */
    126 		shift = bits;
    127 		add |= ((user_token >> PAGE_SHIFT) & ((1UL << bits) - 1UL));
    128 	}
    129 
    130 	return drm_ht_just_insert_please(&dev->map_hash, hash,
    131 					 user_token, 32 - PAGE_SHIFT - 3,
    132 					 shift, add);
    133 }
    134 
    135 /**
    136  * Core function to create a range of memory available for mapping by a
    137  * non-root process.
    138  *
    139  * Adjusts the memory offset to its absolute value according to the mapping
    140  * type.  Adds the map to the map list drm_device::maplist. Adds MTRR's where
    141  * applicable and if supported by the kernel.
    142  */
    143 static int drm_addmap_core(struct drm_device *dev, resource_size_t offset,
    144 			   unsigned int size, enum drm_map_type type,
    145 			   enum drm_map_flags flags,
    146 			   struct drm_map_list **maplist)
    147 {
    148 	struct drm_local_map *map;
    149 	struct drm_map_list *list;
    150 	drm_dma_handle_t *dmah;
    151 	unsigned long user_token;
    152 	int ret;
    153 
    154 	map = kmalloc(sizeof(*map), GFP_KERNEL);
    155 	if (!map)
    156 		return -ENOMEM;
    157 
    158 	map->offset = offset;
    159 	map->size = size;
    160 	map->flags = flags;
    161 	map->type = type;
    162 
    163 	/* Only allow shared memory to be removable since we only keep enough
    164 	 * book keeping information about shared memory to allow for removal
    165 	 * when processes fork.
    166 	 */
    167 	if ((map->flags & _DRM_REMOVABLE) && map->type != _DRM_SHM) {
    168 		kfree(map);
    169 		return -EINVAL;
    170 	}
    171 	DRM_DEBUG("offset = 0x%08llx, size = 0x%08lx, type = %d\n",
    172 		  (unsigned long long)map->offset, map->size, map->type);
    173 
    174 	/* page-align _DRM_SHM maps. They are allocated here so there is no security
    175 	 * hole created by that and it works around various broken drivers that use
    176 	 * a non-aligned quantity to map the SAREA. --BenH
    177 	 */
    178 	if (map->type == _DRM_SHM)
    179 		map->size = PAGE_ALIGN(map->size);
    180 
    181 	if ((map->offset & (~(resource_size_t)PAGE_MASK)) || (map->size & (~PAGE_MASK))) {
    182 		kfree(map);
    183 		return -EINVAL;
    184 	}
    185 	map->mtrr = -1;
    186 	map->handle = NULL;
    187 
    188 	switch (map->type) {
    189 	case _DRM_REGISTERS:
    190 	case _DRM_FRAME_BUFFER:
    191 #ifndef __NetBSD__		/* XXX No idea what this is for...  */
    192 #if !defined(__sparc__) && !defined(__alpha__) && !defined(__ia64__) && !defined(__powerpc64__) && !defined(__x86_64__) && !defined(__arm__)
    193 		if (map->offset + (map->size-1) < map->offset ||
    194 		    map->offset < virt_to_phys(high_memory)) {
    195 			kfree(map);
    196 			return -EINVAL;
    197 		}
    198 #endif
    199 #endif
    200 		/* Some drivers preinitialize some maps, without the X Server
    201 		 * needing to be aware of it.  Therefore, we just return success
    202 		 * when the server tries to create a duplicate map.
    203 		 */
    204 		list = drm_find_matching_map(dev, map);
    205 		if (list != NULL) {
    206 			if (list->map->size != map->size) {
    207 				DRM_DEBUG("Matching maps of type %d with "
    208 					  "mismatched sizes, (%ld vs %ld)\n",
    209 					  map->type, map->size,
    210 					  list->map->size);
    211 				list->map->size = map->size;
    212 			}
    213 
    214 			kfree(map);
    215 			*maplist = list;
    216 			return 0;
    217 		}
    218 
    219 		if (map->type == _DRM_FRAME_BUFFER ||
    220 		    (map->flags & _DRM_WRITE_COMBINING)) {
    221 			map->mtrr =
    222 				arch_phys_wc_add(map->offset, map->size);
    223 		}
    224 		if (map->type == _DRM_REGISTERS) {
    225 #ifdef __NetBSD__
    226 			drm_legacy_ioremap(map, dev);
    227 #else
    228 			if (map->flags & _DRM_WRITE_COMBINING)
    229 				map->handle = ioremap_wc(map->offset,
    230 							 map->size);
    231 			else
    232 				map->handle = ioremap(map->offset, map->size);
    233 #endif
    234 			if (!map->handle) {
    235 				kfree(map);
    236 				return -ENOMEM;
    237 			}
    238 		}
    239 
    240 		break;
    241 	case _DRM_SHM:
    242 		list = drm_find_matching_map(dev, map);
    243 		if (list != NULL) {
    244 			if (list->map->size != map->size) {
    245 				DRM_DEBUG("Matching maps of type %d with "
    246 					  "mismatched sizes, (%ld vs %ld)\n",
    247 					  map->type, map->size, list->map->size);
    248 				list->map->size = map->size;
    249 			}
    250 
    251 			kfree(map);
    252 			*maplist = list;
    253 			return 0;
    254 		}
    255 		map->handle = vmalloc_user(map->size);
    256 		DRM_DEBUG("%lu %d %p\n",
    257 			  map->size, order_base_2(map->size), map->handle);
    258 		if (!map->handle) {
    259 			kfree(map);
    260 			return -ENOMEM;
    261 		}
    262 		map->offset = (unsigned long)map->handle;
    263 		if (map->flags & _DRM_CONTAINS_LOCK) {
    264 			/* Prevent a 2nd X Server from creating a 2nd lock */
    265 			spin_lock(&dev->master->lock.spinlock);
    266 			if (dev->master->lock.hw_lock != NULL) {
    267 				spin_unlock(&dev->master->lock.spinlock);
    268 				vfree(map->handle);
    269 				kfree(map);
    270 				return -EBUSY;
    271 			}
    272 			spin_unlock(&dev->master->lock.spinlock);
    273 			dev->sigdata.lock = dev->master->lock.hw_lock = map->handle;	/* Pointer to lock */
    274 		}
    275 		break;
    276 	case _DRM_AGP: {
    277 		struct drm_agp_mem *entry;
    278 		int valid = 0;
    279 
    280 		if (!dev->agp) {
    281 			kfree(map);
    282 			return -EINVAL;
    283 		}
    284 #ifdef __alpha__
    285 		map->offset += dev->hose->mem_space->start;
    286 #endif
    287 		/* In some cases (i810 driver), user space may have already
    288 		 * added the AGP base itself, because dev->agp->base previously
    289 		 * only got set during AGP enable.  So, only add the base
    290 		 * address if the map's offset isn't already within the
    291 		 * aperture.
    292 		 */
    293 #ifdef __NetBSD__
    294 		if (map->offset < dev->agp->base ||
    295 		    map->offset > dev->agp->base +
    296 		    dev->agp->agp_info.aki_info.ai_aperture_size - 1) {
    297 			map->offset += dev->agp->base;
    298 		}
    299 #else
    300 		if (map->offset < dev->agp->base ||
    301 		    map->offset > dev->agp->base +
    302 		    dev->agp->agp_info.aper_size * 1024 * 1024 - 1) {
    303 			map->offset += dev->agp->base;
    304 		}
    305 #endif
    306 		map->mtrr = dev->agp->agp_mtrr;	/* for getmap */
    307 
    308 		/* This assumes the DRM is in total control of AGP space.
    309 		 * It's not always the case as AGP can be in the control
    310 		 * of user space (i.e. i810 driver). So this loop will get
    311 		 * skipped and we double check that dev->agp->memory is
    312 		 * actually set as well as being invalid before EPERM'ing
    313 		 */
    314 		list_for_each_entry(entry, &dev->agp->memory, head) {
    315 			if ((map->offset >= entry->bound) &&
    316 			    (map->offset + map->size <= entry->bound + entry->pages * PAGE_SIZE)) {
    317 				valid = 1;
    318 				break;
    319 			}
    320 		}
    321 		if (!list_empty(&dev->agp->memory) && !valid) {
    322 			kfree(map);
    323 			return -EPERM;
    324 		}
    325 		DRM_DEBUG("AGP offset = 0x%08llx, size = 0x%08lx\n",
    326 			  (unsigned long long)map->offset, map->size);
    327 
    328 		break;
    329 	}
    330 	case _DRM_SCATTER_GATHER:
    331 		if (!dev->sg) {
    332 			kfree(map);
    333 			return -EINVAL;
    334 		}
    335 		map->offset += (unsigned long)dev->sg->virtual;
    336 		break;
    337 	case _DRM_CONSISTENT:
    338 		/* dma_addr_t is 64bit on i386 with CONFIG_HIGHMEM64G,
    339 		 * As we're limiting the address to 2^32-1 (or less),
    340 		 * casting it down to 32 bits is no problem, but we
    341 		 * need to point to a 64bit variable first. */
    342 		dmah = drm_pci_alloc(dev, map->size, map->size);
    343 		if (!dmah) {
    344 			kfree(map);
    345 			return -ENOMEM;
    346 		}
    347 		map->handle = dmah->vaddr;
    348 		map->offset = (unsigned long)dmah->busaddr;
    349 #ifdef __NetBSD__
    350 		map->lm_data.dmah = dmah;
    351 #else
    352 		kfree(dmah);
    353 #endif
    354 		break;
    355 	default:
    356 		kfree(map);
    357 		return -EINVAL;
    358 	}
    359 
    360 	list = kzalloc(sizeof(*list), GFP_KERNEL);
    361 	if (!list) {
    362 		if (map->type == _DRM_REGISTERS)
    363 #ifdef __NetBSD__
    364 			drm_legacy_ioremapfree(map, dev);
    365 #else
    366 			iounmap(map->handle);
    367 #endif
    368 		kfree(map);
    369 		return -EINVAL;
    370 	}
    371 	list->map = map;
    372 
    373 	mutex_lock(&dev->struct_mutex);
    374 	list_add(&list->head, &dev->maplist);
    375 
    376 	/* Assign a 32-bit handle */
    377 	/* We do it here so that dev->struct_mutex protects the increment */
    378 	user_token = (map->type == _DRM_SHM) ? (unsigned long)map->handle :
    379 		map->offset;
    380 	ret = drm_map_handle(dev, &list->hash, user_token, 0,
    381 			     (map->type == _DRM_SHM));
    382 	if (ret) {
    383 		if (map->type == _DRM_REGISTERS)
    384 #ifdef __NetBSD__		/* XXX What about other map types...?  */
    385 			drm_legacy_ioremapfree(map, dev);
    386 #else
    387 			iounmap(map->handle);
    388 #endif
    389 		kfree(map);
    390 		kfree(list);
    391 		mutex_unlock(&dev->struct_mutex);
    392 		return ret;
    393 	}
    394 
    395 	list->user_token = list->hash.key << PAGE_SHIFT;
    396 	mutex_unlock(&dev->struct_mutex);
    397 
    398 	if (!(map->flags & _DRM_DRIVER))
    399 		list->master = dev->master;
    400 	*maplist = list;
    401 	return 0;
    402 }
    403 
    404 int drm_legacy_addmap(struct drm_device *dev, resource_size_t offset,
    405 		      unsigned int size, enum drm_map_type type,
    406 		      enum drm_map_flags flags, struct drm_local_map **map_ptr)
    407 {
    408 	struct drm_map_list *list;
    409 	int rc;
    410 
    411 	rc = drm_addmap_core(dev, offset, size, type, flags, &list);
    412 	if (!rc)
    413 		*map_ptr = list->map;
    414 	return rc;
    415 }
    416 EXPORT_SYMBOL(drm_legacy_addmap);
    417 
    418 struct drm_local_map *drm_legacy_findmap(struct drm_device *dev,
    419 					 unsigned int token)
    420 {
    421 	struct drm_map_list *_entry;
    422 	list_for_each_entry(_entry, &dev->maplist, head)
    423 		if (_entry->user_token == token)
    424 			return _entry->map;
    425 	return NULL;
    426 }
    427 EXPORT_SYMBOL(drm_legacy_findmap);
    428 
    429 /**
    430  * Ioctl to specify a range of memory that is available for mapping by a
    431  * non-root process.
    432  *
    433  * \param inode device inode.
    434  * \param file_priv DRM file private.
    435  * \param cmd command.
    436  * \param arg pointer to a drm_map structure.
    437  * \return zero on success or a negative value on error.
    438  *
    439  */
    440 int drm_legacy_addmap_ioctl(struct drm_device *dev, void *data,
    441 			    struct drm_file *file_priv)
    442 {
    443 	struct drm_map *map = data;
    444 	struct drm_map_list *maplist;
    445 	int err;
    446 
    447 	if (!(capable(CAP_SYS_ADMIN) || map->type == _DRM_AGP || map->type == _DRM_SHM))
    448 		return -EPERM;
    449 
    450 	if (!drm_core_check_feature(dev, DRIVER_KMS_LEGACY_CONTEXT) &&
    451 	    !drm_core_check_feature(dev, DRIVER_LEGACY))
    452 		return -EOPNOTSUPP;
    453 
    454 	err = drm_addmap_core(dev, map->offset, map->size, map->type,
    455 			      map->flags, &maplist);
    456 
    457 	if (err)
    458 		return err;
    459 
    460 	/* avoid a warning on 64-bit, this casting isn't very nice, but the API is set so too late */
    461 	map->handle = (void *)(unsigned long)maplist->user_token;
    462 
    463 	/*
    464 	 * It appears that there are no users of this value whatsoever --
    465 	 * drmAddMap just discards it.  Let's not encourage its use.
    466 	 * (Keeping drm_addmap_core's returned mtrr value would be wrong --
    467 	 *  it's not a real mtrr index anymore.)
    468 	 */
    469 	map->mtrr = -1;
    470 
    471 	return 0;
    472 }
    473 
    474 /*
    475  * Get a mapping information.
    476  *
    477  * \param inode device inode.
    478  * \param file_priv DRM file private.
    479  * \param cmd command.
    480  * \param arg user argument, pointing to a drm_map structure.
    481  *
    482  * \return zero on success or a negative number on failure.
    483  *
    484  * Searches for the mapping with the specified offset and copies its information
    485  * into userspace
    486  */
    487 int drm_legacy_getmap_ioctl(struct drm_device *dev, void *data,
    488 			    struct drm_file *file_priv)
    489 {
    490 	struct drm_map *map = data;
    491 	struct drm_map_list *r_list = NULL;
    492 	struct list_head *list;
    493 	int idx;
    494 	int i;
    495 
    496 	if (!drm_core_check_feature(dev, DRIVER_KMS_LEGACY_CONTEXT) &&
    497 	    !drm_core_check_feature(dev, DRIVER_LEGACY))
    498 		return -EOPNOTSUPP;
    499 
    500 	idx = map->offset;
    501 	if (idx < 0)
    502 		return -EINVAL;
    503 
    504 	i = 0;
    505 	mutex_lock(&dev->struct_mutex);
    506 	list_for_each(list, &dev->maplist) {
    507 		if (i == idx) {
    508 			r_list = list_entry(list, struct drm_map_list, head);
    509 			break;
    510 		}
    511 		i++;
    512 	}
    513 	if (!r_list || !r_list->map) {
    514 		mutex_unlock(&dev->struct_mutex);
    515 		return -EINVAL;
    516 	}
    517 
    518 	map->offset = r_list->map->offset;
    519 	map->size = r_list->map->size;
    520 	map->type = r_list->map->type;
    521 	map->flags = r_list->map->flags;
    522 	map->handle = (void *)(unsigned long) r_list->user_token;
    523 	map->mtrr = arch_phys_wc_index(r_list->map->mtrr);
    524 
    525 	mutex_unlock(&dev->struct_mutex);
    526 
    527 	return 0;
    528 }
    529 
    530 /**
    531  * Remove a map private from list and deallocate resources if the mapping
    532  * isn't in use.
    533  *
    534  * Searches the map on drm_device::maplist, removes it from the list, see if
    535  * it's being used, and free any associated resource (such as MTRR's) if it's not
    536  * being on use.
    537  *
    538  * \sa drm_legacy_addmap
    539  */
    540 int drm_legacy_rmmap_locked(struct drm_device *dev, struct drm_local_map *map)
    541 {
    542 	struct drm_map_list *r_list = NULL, *list_t;
    543 #ifndef __NetBSD__
    544 	drm_dma_handle_t dmah;
    545 #endif
    546 	int found = 0;
    547 	struct drm_master *master;
    548 
    549 	/* Find the list entry for the map and remove it */
    550 	list_for_each_entry_safe(r_list, list_t, &dev->maplist, head) {
    551 		if (r_list->map == map) {
    552 			master = r_list->master;
    553 			list_del(&r_list->head);
    554 			drm_ht_remove_key(&dev->map_hash,
    555 					  r_list->user_token >> PAGE_SHIFT);
    556 			kfree(r_list);
    557 			found = 1;
    558 			break;
    559 		}
    560 	}
    561 
    562 	if (!found)
    563 		return -EINVAL;
    564 
    565 	switch (map->type) {
    566 	case _DRM_REGISTERS:
    567 #ifdef __NetBSD__
    568 		drm_legacy_ioremapfree(map, dev);
    569 #else
    570 		iounmap(map->handle);
    571 #endif
    572 		/* FALLTHROUGH */
    573 	case _DRM_FRAME_BUFFER:
    574 		arch_phys_wc_del(map->mtrr);
    575 		break;
    576 	case _DRM_SHM:
    577 		if (master && (map->flags & _DRM_CONTAINS_LOCK)) {
    578 			spin_lock(&master->lock.spinlock);
    579 			/*
    580 			 * If we successfully removed this mapping,
    581 			 * then the mapping must have been there in the
    582 			 * first place, and we must have had a
    583 			 * heavyweight lock, so we assert here instead
    584 			 * of just checking and failing.
    585 			 *
    586 			 * XXX What about the _DRM_CONTAINS_LOCK flag?
    587 			 * Where is that supposed to be set?  Is it
    588 			 * equivalent to having a master set?
    589 			 *
    590 			 * XXX There is copypasta of this in
    591 			 * drm_lock.c, drm_legacy_lock_master_cleanup.
    592 			 */
    593 			BUG_ON(master->lock.hw_lock == NULL);
    594 			if (dev->sigdata.lock == master->lock.hw_lock)
    595 				dev->sigdata.lock = NULL;
    596 			master->lock.hw_lock = NULL;   /* SHM removed */
    597 			master->lock.file_priv = NULL;
    598 #ifdef __NetBSD__
    599 			DRM_SPIN_WAKEUP_ALL(&master->lock.lock_queue,
    600 			    &master->lock.spinlock);
    601 #else
    602 			wake_up_interruptible_all(&master->lock.lock_queue);
    603 #endif
    604 			spin_unlock(&master->lock.spinlock);
    605 		}
    606 		vfree(map->handle);
    607 		break;
    608 	case _DRM_AGP:
    609 	case _DRM_SCATTER_GATHER:
    610 		break;
    611 	case _DRM_CONSISTENT:
    612 #ifdef __NetBSD__
    613 		drm_pci_free(dev, map->lm_data.dmah);
    614 #else
    615 		dmah.vaddr = map->handle;
    616 		dmah.busaddr = map->offset;
    617 		dmah.size = map->size;
    618 		__drm_legacy_pci_free(dev, &dmah);
    619 #endif
    620 		break;
    621 	}
    622 	kfree(map);
    623 
    624 	return 0;
    625 }
    626 EXPORT_SYMBOL(drm_legacy_rmmap_locked);
    627 
    628 void drm_legacy_rmmap(struct drm_device *dev, struct drm_local_map *map)
    629 {
    630 	if (!drm_core_check_feature(dev, DRIVER_KMS_LEGACY_CONTEXT) &&
    631 	    !drm_core_check_feature(dev, DRIVER_LEGACY))
    632 		return;
    633 
    634 	mutex_lock(&dev->struct_mutex);
    635 	drm_legacy_rmmap_locked(dev, map);
    636 	mutex_unlock(&dev->struct_mutex);
    637 }
    638 EXPORT_SYMBOL(drm_legacy_rmmap);
    639 
    640 void drm_legacy_master_rmmaps(struct drm_device *dev, struct drm_master *master)
    641 {
    642 	struct drm_map_list *r_list, *list_temp;
    643 
    644 	if (!drm_core_check_feature(dev, DRIVER_LEGACY))
    645 		return;
    646 
    647 	mutex_lock(&dev->struct_mutex);
    648 	list_for_each_entry_safe(r_list, list_temp, &dev->maplist, head) {
    649 		if (r_list->master == master) {
    650 			drm_legacy_rmmap_locked(dev, r_list->map);
    651 			r_list = NULL;
    652 		}
    653 	}
    654 	mutex_unlock(&dev->struct_mutex);
    655 }
    656 
    657 void drm_legacy_rmmaps(struct drm_device *dev)
    658 {
    659 	struct drm_map_list *r_list, *list_temp;
    660 
    661 	list_for_each_entry_safe(r_list, list_temp, &dev->maplist, head)
    662 		drm_legacy_rmmap(dev, r_list->map);
    663 }
    664 
    665 /* The rmmap ioctl appears to be unnecessary.  All mappings are torn down on
    666  * the last close of the device, and this is necessary for cleanup when things
    667  * exit uncleanly.  Therefore, having userland manually remove mappings seems
    668  * like a pointless exercise since they're going away anyway.
    669  *
    670  * One use case might be after addmap is allowed for normal users for SHM and
    671  * gets used by drivers that the server doesn't need to care about.  This seems
    672  * unlikely.
    673  *
    674  * \param inode device inode.
    675  * \param file_priv DRM file private.
    676  * \param cmd command.
    677  * \param arg pointer to a struct drm_map structure.
    678  * \return zero on success or a negative value on error.
    679  */
    680 int drm_legacy_rmmap_ioctl(struct drm_device *dev, void *data,
    681 			   struct drm_file *file_priv)
    682 {
    683 	struct drm_map *request = data;
    684 	struct drm_local_map *map = NULL;
    685 	struct drm_map_list *r_list;
    686 	int ret;
    687 
    688 	if (!drm_core_check_feature(dev, DRIVER_KMS_LEGACY_CONTEXT) &&
    689 	    !drm_core_check_feature(dev, DRIVER_LEGACY))
    690 		return -EOPNOTSUPP;
    691 
    692 	mutex_lock(&dev->struct_mutex);
    693 	list_for_each_entry(r_list, &dev->maplist, head) {
    694 		if (r_list->map &&
    695 		    r_list->user_token == (unsigned long)request->handle &&
    696 		    r_list->map->flags & _DRM_REMOVABLE) {
    697 			map = r_list->map;
    698 			break;
    699 		}
    700 	}
    701 
    702 	/* List has wrapped around to the head pointer, or it's empty we didn't
    703 	 * find anything.
    704 	 */
    705 	if (list_empty(&dev->maplist) || !map) {
    706 		mutex_unlock(&dev->struct_mutex);
    707 		return -EINVAL;
    708 	}
    709 
    710 	/* Register and framebuffer maps are permanent */
    711 	if ((map->type == _DRM_REGISTERS) || (map->type == _DRM_FRAME_BUFFER)) {
    712 		mutex_unlock(&dev->struct_mutex);
    713 		return 0;
    714 	}
    715 
    716 	ret = drm_legacy_rmmap_locked(dev, map);
    717 
    718 	mutex_unlock(&dev->struct_mutex);
    719 
    720 	return ret;
    721 }
    722 
    723 /**
    724  * Cleanup after an error on one of the addbufs() functions.
    725  *
    726  * \param dev DRM device.
    727  * \param entry buffer entry where the error occurred.
    728  *
    729  * Frees any pages and buffers associated with the given entry.
    730  */
    731 static void drm_cleanup_buf_error(struct drm_device *dev,
    732 				  struct drm_buf_entry *entry)
    733 {
    734 	int i;
    735 
    736 	if (entry->seg_count) {
    737 		for (i = 0; i < entry->seg_count; i++) {
    738 			if (entry->seglist[i]) {
    739 				drm_pci_free(dev, entry->seglist[i]);
    740 			}
    741 		}
    742 		kfree(entry->seglist);
    743 
    744 		entry->seg_count = 0;
    745 	}
    746 
    747 	if (entry->buf_count) {
    748 		for (i = 0; i < entry->buf_count; i++) {
    749 			kfree(entry->buflist[i].dev_private);
    750 		}
    751 		kfree(entry->buflist);
    752 
    753 		entry->buf_count = 0;
    754 	}
    755 }
    756 
    757 #if IS_ENABLED(CONFIG_AGP)
    758 /**
    759  * Add AGP buffers for DMA transfers.
    760  *
    761  * \param dev struct drm_device to which the buffers are to be added.
    762  * \param request pointer to a struct drm_buf_desc describing the request.
    763  * \return zero on success or a negative number on failure.
    764  *
    765  * After some sanity checks creates a drm_buf structure for each buffer and
    766  * reallocates the buffer list of the same size order to accommodate the new
    767  * buffers.
    768  */
    769 int drm_legacy_addbufs_agp(struct drm_device *dev,
    770 			   struct drm_buf_desc *request)
    771 {
    772 	struct drm_device_dma *dma = dev->dma;
    773 	struct drm_buf_entry *entry;
    774 	struct drm_agp_mem *agp_entry;
    775 	struct drm_buf *buf;
    776 	unsigned long offset;
    777 	unsigned long agp_offset;
    778 	int count;
    779 	int order;
    780 	int size;
    781 	int alignment;
    782 	int page_order;
    783 	int total;
    784 	int byte_count;
    785 	int i, valid;
    786 	struct drm_buf **temp_buflist;
    787 
    788 	if (!dma)
    789 		return -EINVAL;
    790 
    791 	count = request->count;
    792 	order = order_base_2(request->size);
    793 	size = 1 << order;
    794 
    795 	alignment = (request->flags & _DRM_PAGE_ALIGN)
    796 	    ? PAGE_ALIGN(size) : size;
    797 	page_order = order - PAGE_SHIFT > 0 ? order - PAGE_SHIFT : 0;
    798 	total = PAGE_SIZE << page_order;
    799 
    800 	byte_count = 0;
    801 	agp_offset = dev->agp->base + request->agp_start;
    802 
    803 	DRM_DEBUG("count:      %d\n", count);
    804 	DRM_DEBUG("order:      %d\n", order);
    805 	DRM_DEBUG("size:       %d\n", size);
    806 	DRM_DEBUG("agp_offset: %lx\n", agp_offset);
    807 	DRM_DEBUG("alignment:  %d\n", alignment);
    808 	DRM_DEBUG("page_order: %d\n", page_order);
    809 	DRM_DEBUG("total:      %d\n", total);
    810 
    811 	if (order < DRM_MIN_ORDER || order > DRM_MAX_ORDER)
    812 		return -EINVAL;
    813 
    814 	/* Make sure buffers are located in AGP memory that we own */
    815 	valid = 0;
    816 	list_for_each_entry(agp_entry, &dev->agp->memory, head) {
    817 		if ((agp_offset >= agp_entry->bound) &&
    818 		    (agp_offset + total * count <= agp_entry->bound + agp_entry->pages * PAGE_SIZE)) {
    819 			valid = 1;
    820 			break;
    821 		}
    822 	}
    823 	if (!list_empty(&dev->agp->memory) && !valid) {
    824 		DRM_DEBUG("zone invalid\n");
    825 		return -EINVAL;
    826 	}
    827 	spin_lock(&dev->buf_lock);
    828 	if (dev->buf_use) {
    829 		spin_unlock(&dev->buf_lock);
    830 		return -EBUSY;
    831 	}
    832 	atomic_inc(&dev->buf_alloc);
    833 	spin_unlock(&dev->buf_lock);
    834 
    835 	mutex_lock(&dev->struct_mutex);
    836 	entry = &dma->bufs[order];
    837 	if (entry->buf_count) {
    838 		mutex_unlock(&dev->struct_mutex);
    839 		atomic_dec(&dev->buf_alloc);
    840 		return -ENOMEM;	/* May only call once for each order */
    841 	}
    842 
    843 	if (count < 0 || count > 4096) {
    844 		mutex_unlock(&dev->struct_mutex);
    845 		atomic_dec(&dev->buf_alloc);
    846 		return -EINVAL;
    847 	}
    848 
    849 	entry->buflist = kcalloc(count, sizeof(*entry->buflist), GFP_KERNEL);
    850 	if (!entry->buflist) {
    851 		mutex_unlock(&dev->struct_mutex);
    852 		atomic_dec(&dev->buf_alloc);
    853 		return -ENOMEM;
    854 	}
    855 
    856 	entry->buf_size = size;
    857 	entry->page_order = page_order;
    858 
    859 	offset = 0;
    860 
    861 	while (entry->buf_count < count) {
    862 		buf = &entry->buflist[entry->buf_count];
    863 		buf->idx = dma->buf_count + entry->buf_count;
    864 		buf->total = alignment;
    865 		buf->order = order;
    866 		buf->used = 0;
    867 
    868 		buf->offset = (dma->byte_count + offset);
    869 		buf->bus_address = agp_offset + offset;
    870 		buf->address = (void *)(agp_offset + offset);
    871 		buf->next = NULL;
    872 		buf->waiting = 0;
    873 		buf->pending = 0;
    874 		buf->file_priv = NULL;
    875 
    876 		buf->dev_priv_size = dev->driver->dev_priv_size;
    877 		buf->dev_private = kzalloc(buf->dev_priv_size, GFP_KERNEL);
    878 		if (!buf->dev_private) {
    879 			/* Set count correctly so we free the proper amount. */
    880 			entry->buf_count = count;
    881 			drm_cleanup_buf_error(dev, entry);
    882 			mutex_unlock(&dev->struct_mutex);
    883 			atomic_dec(&dev->buf_alloc);
    884 			return -ENOMEM;
    885 		}
    886 
    887 		DRM_DEBUG("buffer %d @ %p\n", entry->buf_count, buf->address);
    888 
    889 		offset += alignment;
    890 		entry->buf_count++;
    891 		byte_count += PAGE_SIZE << page_order;
    892 	}
    893 
    894 	DRM_DEBUG("byte_count: %d\n", byte_count);
    895 
    896 	temp_buflist = krealloc(dma->buflist,
    897 				(dma->buf_count + entry->buf_count) *
    898 				sizeof(*dma->buflist), GFP_KERNEL);
    899 	if (!temp_buflist) {
    900 		/* Free the entry because it isn't valid */
    901 		drm_cleanup_buf_error(dev, entry);
    902 		mutex_unlock(&dev->struct_mutex);
    903 		atomic_dec(&dev->buf_alloc);
    904 		return -ENOMEM;
    905 	}
    906 	dma->buflist = temp_buflist;
    907 
    908 	for (i = 0; i < entry->buf_count; i++) {
    909 		dma->buflist[i + dma->buf_count] = &entry->buflist[i];
    910 	}
    911 
    912 	dma->buf_count += entry->buf_count;
    913 	dma->seg_count += entry->seg_count;
    914 	dma->page_count += byte_count >> PAGE_SHIFT;
    915 	dma->byte_count += byte_count;
    916 
    917 	DRM_DEBUG("dma->buf_count : %d\n", dma->buf_count);
    918 	DRM_DEBUG("entry->buf_count : %d\n", entry->buf_count);
    919 
    920 	mutex_unlock(&dev->struct_mutex);
    921 
    922 	request->count = entry->buf_count;
    923 	request->size = size;
    924 
    925 	dma->flags = _DRM_DMA_USE_AGP;
    926 
    927 	atomic_dec(&dev->buf_alloc);
    928 	return 0;
    929 }
    930 EXPORT_SYMBOL(drm_legacy_addbufs_agp);
    931 #endif /* CONFIG_AGP */
    932 
    933 int drm_legacy_addbufs_pci(struct drm_device *dev,
    934 			   struct drm_buf_desc *request)
    935 {
    936 	struct drm_device_dma *dma = dev->dma;
    937 	int count;
    938 	int order;
    939 	int size;
    940 	int total;
    941 	int page_order;
    942 	struct drm_buf_entry *entry;
    943 	drm_dma_handle_t *dmah;
    944 	struct drm_buf *buf;
    945 	int alignment;
    946 	unsigned long offset;
    947 	int i;
    948 	int byte_count;
    949 	int page_count;
    950 	unsigned long *temp_pagelist;
    951 	struct drm_buf **temp_buflist;
    952 
    953 	if (!drm_core_check_feature(dev, DRIVER_PCI_DMA))
    954 		return -EOPNOTSUPP;
    955 
    956 	if (!dma)
    957 		return -EINVAL;
    958 
    959 	if (!capable(CAP_SYS_ADMIN))
    960 		return -EPERM;
    961 
    962 	count = request->count;
    963 	order = order_base_2(request->size);
    964 	size = 1 << order;
    965 
    966 	DRM_DEBUG("count=%d, size=%d (%d), order=%d\n",
    967 		  request->count, request->size, size, order);
    968 
    969 	if (order < DRM_MIN_ORDER || order > DRM_MAX_ORDER)
    970 		return -EINVAL;
    971 
    972 	alignment = (request->flags & _DRM_PAGE_ALIGN)
    973 	    ? PAGE_ALIGN(size) : size;
    974 	page_order = order - PAGE_SHIFT > 0 ? order - PAGE_SHIFT : 0;
    975 	total = PAGE_SIZE << page_order;
    976 
    977 	spin_lock(&dev->buf_lock);
    978 	if (dev->buf_use) {
    979 		spin_unlock(&dev->buf_lock);
    980 		return -EBUSY;
    981 	}
    982 	atomic_inc(&dev->buf_alloc);
    983 	spin_unlock(&dev->buf_lock);
    984 
    985 	mutex_lock(&dev->struct_mutex);
    986 	entry = &dma->bufs[order];
    987 	if (entry->buf_count) {
    988 		mutex_unlock(&dev->struct_mutex);
    989 		atomic_dec(&dev->buf_alloc);
    990 		return -ENOMEM;	/* May only call once for each order */
    991 	}
    992 
    993 	if (count < 0 || count > 4096) {
    994 		mutex_unlock(&dev->struct_mutex);
    995 		atomic_dec(&dev->buf_alloc);
    996 		return -EINVAL;
    997 	}
    998 
    999 	entry->buflist = kcalloc(count, sizeof(*entry->buflist), GFP_KERNEL);
   1000 	if (!entry->buflist) {
   1001 		mutex_unlock(&dev->struct_mutex);
   1002 		atomic_dec(&dev->buf_alloc);
   1003 		return -ENOMEM;
   1004 	}
   1005 
   1006 	entry->seglist = kcalloc(count, sizeof(*entry->seglist), GFP_KERNEL);
   1007 	if (!entry->seglist) {
   1008 		kfree(entry->buflist);
   1009 		mutex_unlock(&dev->struct_mutex);
   1010 		atomic_dec(&dev->buf_alloc);
   1011 		return -ENOMEM;
   1012 	}
   1013 
   1014 	/* Keep the original pagelist until we know all the allocations
   1015 	 * have succeeded
   1016 	 */
   1017 	temp_pagelist = kmalloc_array(dma->page_count + (count << page_order),
   1018 				      sizeof(*dma->pagelist),
   1019 				      GFP_KERNEL);
   1020 	if (!temp_pagelist) {
   1021 		kfree(entry->buflist);
   1022 		kfree(entry->seglist);
   1023 		mutex_unlock(&dev->struct_mutex);
   1024 		atomic_dec(&dev->buf_alloc);
   1025 		return -ENOMEM;
   1026 	}
   1027 	memcpy(temp_pagelist,
   1028 	       dma->pagelist, dma->page_count * sizeof(*dma->pagelist));
   1029 	DRM_DEBUG("pagelist: %d entries\n",
   1030 		  dma->page_count + (count << page_order));
   1031 
   1032 	entry->buf_size = size;
   1033 	entry->page_order = page_order;
   1034 	byte_count = 0;
   1035 	page_count = 0;
   1036 
   1037 	while (entry->buf_count < count) {
   1038 
   1039 		dmah = drm_pci_alloc(dev, PAGE_SIZE << page_order, 0x1000);
   1040 
   1041 		if (!dmah) {
   1042 			/* Set count correctly so we free the proper amount. */
   1043 			entry->buf_count = count;
   1044 			entry->seg_count = count;
   1045 			drm_cleanup_buf_error(dev, entry);
   1046 			kfree(temp_pagelist);
   1047 			mutex_unlock(&dev->struct_mutex);
   1048 			atomic_dec(&dev->buf_alloc);
   1049 			return -ENOMEM;
   1050 		}
   1051 		entry->seglist[entry->seg_count++] = dmah;
   1052 		for (i = 0; i < (1 << page_order); i++) {
   1053 			DRM_DEBUG("page %d @ 0x%08lx\n",
   1054 				  dma->page_count + page_count,
   1055 				  (unsigned long)dmah->vaddr + PAGE_SIZE * i);
   1056 			temp_pagelist[dma->page_count + page_count++]
   1057 				= (unsigned long)dmah->vaddr + PAGE_SIZE * i;
   1058 		}
   1059 		for (offset = 0;
   1060 		     offset + size <= total && entry->buf_count < count;
   1061 		     offset += alignment, ++entry->buf_count) {
   1062 			buf = &entry->buflist[entry->buf_count];
   1063 			buf->idx = dma->buf_count + entry->buf_count;
   1064 			buf->total = alignment;
   1065 			buf->order = order;
   1066 			buf->used = 0;
   1067 			buf->offset = (dma->byte_count + byte_count + offset);
   1068 			buf->address = (void *)(dmah->vaddr + offset);
   1069 			buf->bus_address = dmah->busaddr + offset;
   1070 			buf->next = NULL;
   1071 			buf->waiting = 0;
   1072 			buf->pending = 0;
   1073 			buf->file_priv = NULL;
   1074 
   1075 			buf->dev_priv_size = dev->driver->dev_priv_size;
   1076 			buf->dev_private = kzalloc(buf->dev_priv_size,
   1077 						GFP_KERNEL);
   1078 			if (!buf->dev_private) {
   1079 				/* Set count correctly so we free the proper amount. */
   1080 				entry->buf_count = count;
   1081 				entry->seg_count = count;
   1082 				drm_cleanup_buf_error(dev, entry);
   1083 				kfree(temp_pagelist);
   1084 				mutex_unlock(&dev->struct_mutex);
   1085 				atomic_dec(&dev->buf_alloc);
   1086 				return -ENOMEM;
   1087 			}
   1088 
   1089 			DRM_DEBUG("buffer %d @ %p\n",
   1090 				  entry->buf_count, buf->address);
   1091 		}
   1092 		byte_count += PAGE_SIZE << page_order;
   1093 	}
   1094 
   1095 	temp_buflist = krealloc(dma->buflist,
   1096 				(dma->buf_count + entry->buf_count) *
   1097 				sizeof(*dma->buflist), GFP_KERNEL);
   1098 	if (!temp_buflist) {
   1099 		/* Free the entry because it isn't valid */
   1100 		drm_cleanup_buf_error(dev, entry);
   1101 		kfree(temp_pagelist);
   1102 		mutex_unlock(&dev->struct_mutex);
   1103 		atomic_dec(&dev->buf_alloc);
   1104 		return -ENOMEM;
   1105 	}
   1106 	dma->buflist = temp_buflist;
   1107 
   1108 	for (i = 0; i < entry->buf_count; i++) {
   1109 		dma->buflist[i + dma->buf_count] = &entry->buflist[i];
   1110 	}
   1111 
   1112 	/* No allocations failed, so now we can replace the original pagelist
   1113 	 * with the new one.
   1114 	 */
   1115 	if (dma->page_count) {
   1116 		kfree(dma->pagelist);
   1117 	}
   1118 	dma->pagelist = temp_pagelist;
   1119 
   1120 	dma->buf_count += entry->buf_count;
   1121 	dma->seg_count += entry->seg_count;
   1122 	dma->page_count += entry->seg_count << page_order;
   1123 	dma->byte_count += PAGE_SIZE * (entry->seg_count << page_order);
   1124 
   1125 	mutex_unlock(&dev->struct_mutex);
   1126 
   1127 	request->count = entry->buf_count;
   1128 	request->size = size;
   1129 
   1130 	if (request->flags & _DRM_PCI_BUFFER_RO)
   1131 		dma->flags = _DRM_DMA_USE_PCI_RO;
   1132 
   1133 	atomic_dec(&dev->buf_alloc);
   1134 	return 0;
   1135 
   1136 }
   1137 EXPORT_SYMBOL(drm_legacy_addbufs_pci);
   1138 
   1139 static int drm_legacy_addbufs_sg(struct drm_device *dev,
   1140 				 struct drm_buf_desc *request)
   1141 {
   1142 	struct drm_device_dma *dma = dev->dma;
   1143 	struct drm_buf_entry *entry;
   1144 	struct drm_buf *buf;
   1145 	unsigned long offset;
   1146 	unsigned long agp_offset;
   1147 	int count;
   1148 	int order;
   1149 	int size;
   1150 	int alignment;
   1151 	int page_order;
   1152 	int total;
   1153 	int byte_count;
   1154 	int i;
   1155 	struct drm_buf **temp_buflist;
   1156 
   1157 	if (!drm_core_check_feature(dev, DRIVER_SG))
   1158 		return -EOPNOTSUPP;
   1159 
   1160 	if (!dma)
   1161 		return -EINVAL;
   1162 
   1163 	if (!capable(CAP_SYS_ADMIN))
   1164 		return -EPERM;
   1165 
   1166 	count = request->count;
   1167 	order = order_base_2(request->size);
   1168 	size = 1 << order;
   1169 
   1170 	alignment = (request->flags & _DRM_PAGE_ALIGN)
   1171 	    ? PAGE_ALIGN(size) : size;
   1172 	page_order = order - PAGE_SHIFT > 0 ? order - PAGE_SHIFT : 0;
   1173 	total = PAGE_SIZE << page_order;
   1174 
   1175 	byte_count = 0;
   1176 	agp_offset = request->agp_start;
   1177 
   1178 	DRM_DEBUG("count:      %d\n", count);
   1179 	DRM_DEBUG("order:      %d\n", order);
   1180 	DRM_DEBUG("size:       %d\n", size);
   1181 	DRM_DEBUG("agp_offset: %lu\n", agp_offset);
   1182 	DRM_DEBUG("alignment:  %d\n", alignment);
   1183 	DRM_DEBUG("page_order: %d\n", page_order);
   1184 	DRM_DEBUG("total:      %d\n", total);
   1185 
   1186 	if (order < DRM_MIN_ORDER || order > DRM_MAX_ORDER)
   1187 		return -EINVAL;
   1188 
   1189 	spin_lock(&dev->buf_lock);
   1190 	if (dev->buf_use) {
   1191 		spin_unlock(&dev->buf_lock);
   1192 		return -EBUSY;
   1193 	}
   1194 	atomic_inc(&dev->buf_alloc);
   1195 	spin_unlock(&dev->buf_lock);
   1196 
   1197 	mutex_lock(&dev->struct_mutex);
   1198 	entry = &dma->bufs[order];
   1199 	if (entry->buf_count) {
   1200 		mutex_unlock(&dev->struct_mutex);
   1201 		atomic_dec(&dev->buf_alloc);
   1202 		return -ENOMEM;	/* May only call once for each order */
   1203 	}
   1204 
   1205 	if (count < 0 || count > 4096) {
   1206 		mutex_unlock(&dev->struct_mutex);
   1207 		atomic_dec(&dev->buf_alloc);
   1208 		return -EINVAL;
   1209 	}
   1210 
   1211 	entry->buflist = kcalloc(count, sizeof(*entry->buflist), GFP_KERNEL);
   1212 	if (!entry->buflist) {
   1213 		mutex_unlock(&dev->struct_mutex);
   1214 		atomic_dec(&dev->buf_alloc);
   1215 		return -ENOMEM;
   1216 	}
   1217 
   1218 	entry->buf_size = size;
   1219 	entry->page_order = page_order;
   1220 
   1221 	offset = 0;
   1222 
   1223 	while (entry->buf_count < count) {
   1224 		buf = &entry->buflist[entry->buf_count];
   1225 		buf->idx = dma->buf_count + entry->buf_count;
   1226 		buf->total = alignment;
   1227 		buf->order = order;
   1228 		buf->used = 0;
   1229 
   1230 		buf->offset = (dma->byte_count + offset);
   1231 		buf->bus_address = agp_offset + offset;
   1232 		buf->address = (void *)(agp_offset + offset
   1233 					+ (unsigned long)dev->sg->virtual);
   1234 		buf->next = NULL;
   1235 		buf->waiting = 0;
   1236 		buf->pending = 0;
   1237 		buf->file_priv = NULL;
   1238 
   1239 		buf->dev_priv_size = dev->driver->dev_priv_size;
   1240 		buf->dev_private = kzalloc(buf->dev_priv_size, GFP_KERNEL);
   1241 		if (!buf->dev_private) {
   1242 			/* Set count correctly so we free the proper amount. */
   1243 			entry->buf_count = count;
   1244 			drm_cleanup_buf_error(dev, entry);
   1245 			mutex_unlock(&dev->struct_mutex);
   1246 			atomic_dec(&dev->buf_alloc);
   1247 			return -ENOMEM;
   1248 		}
   1249 
   1250 		DRM_DEBUG("buffer %d @ %p\n", entry->buf_count, buf->address);
   1251 
   1252 		offset += alignment;
   1253 		entry->buf_count++;
   1254 		byte_count += PAGE_SIZE << page_order;
   1255 	}
   1256 
   1257 	DRM_DEBUG("byte_count: %d\n", byte_count);
   1258 
   1259 	temp_buflist = krealloc(dma->buflist,
   1260 				(dma->buf_count + entry->buf_count) *
   1261 				sizeof(*dma->buflist), GFP_KERNEL);
   1262 	if (!temp_buflist) {
   1263 		/* Free the entry because it isn't valid */
   1264 		drm_cleanup_buf_error(dev, entry);
   1265 		mutex_unlock(&dev->struct_mutex);
   1266 		atomic_dec(&dev->buf_alloc);
   1267 		return -ENOMEM;
   1268 	}
   1269 	dma->buflist = temp_buflist;
   1270 
   1271 	for (i = 0; i < entry->buf_count; i++) {
   1272 		dma->buflist[i + dma->buf_count] = &entry->buflist[i];
   1273 	}
   1274 
   1275 	dma->buf_count += entry->buf_count;
   1276 	dma->seg_count += entry->seg_count;
   1277 	dma->page_count += byte_count >> PAGE_SHIFT;
   1278 	dma->byte_count += byte_count;
   1279 
   1280 	DRM_DEBUG("dma->buf_count : %d\n", dma->buf_count);
   1281 	DRM_DEBUG("entry->buf_count : %d\n", entry->buf_count);
   1282 
   1283 	mutex_unlock(&dev->struct_mutex);
   1284 
   1285 	request->count = entry->buf_count;
   1286 	request->size = size;
   1287 
   1288 	dma->flags = _DRM_DMA_USE_SG;
   1289 
   1290 	atomic_dec(&dev->buf_alloc);
   1291 	return 0;
   1292 }
   1293 
   1294 /**
   1295  * Add buffers for DMA transfers (ioctl).
   1296  *
   1297  * \param inode device inode.
   1298  * \param file_priv DRM file private.
   1299  * \param cmd command.
   1300  * \param arg pointer to a struct drm_buf_desc request.
   1301  * \return zero on success or a negative number on failure.
   1302  *
   1303  * According with the memory type specified in drm_buf_desc::flags and the
   1304  * build options, it dispatches the call either to addbufs_agp(),
   1305  * addbufs_sg() or addbufs_pci() for AGP, scatter-gather or consistent
   1306  * PCI memory respectively.
   1307  */
   1308 int drm_legacy_addbufs(struct drm_device *dev, void *data,
   1309 		       struct drm_file *file_priv)
   1310 {
   1311 	struct drm_buf_desc *request = data;
   1312 	int ret;
   1313 
   1314 	if (!drm_core_check_feature(dev, DRIVER_LEGACY))
   1315 		return -EOPNOTSUPP;
   1316 
   1317 	if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA))
   1318 		return -EOPNOTSUPP;
   1319 
   1320 #if IS_ENABLED(CONFIG_AGP)
   1321 	if (request->flags & _DRM_AGP_BUFFER)
   1322 		ret = drm_legacy_addbufs_agp(dev, request);
   1323 	else
   1324 #endif
   1325 	if (request->flags & _DRM_SG_BUFFER)
   1326 		ret = drm_legacy_addbufs_sg(dev, request);
   1327 	else if (request->flags & _DRM_FB_BUFFER)
   1328 		ret = -EINVAL;
   1329 	else
   1330 		ret = drm_legacy_addbufs_pci(dev, request);
   1331 
   1332 	return ret;
   1333 }
   1334 
   1335 /**
   1336  * Get information about the buffer mappings.
   1337  *
   1338  * This was originally mean for debugging purposes, or by a sophisticated
   1339  * client library to determine how best to use the available buffers (e.g.,
   1340  * large buffers can be used for image transfer).
   1341  *
   1342  * \param inode device inode.
   1343  * \param file_priv DRM file private.
   1344  * \param cmd command.
   1345  * \param arg pointer to a drm_buf_info structure.
   1346  * \return zero on success or a negative number on failure.
   1347  *
   1348  * Increments drm_device::buf_use while holding the drm_device::buf_lock
   1349  * lock, preventing of allocating more buffers after this call. Information
   1350  * about each requested buffer is then copied into user space.
   1351  */
   1352 int __drm_legacy_infobufs(struct drm_device *dev,
   1353 			void *data, int *p,
   1354 			int (*f)(void *, int, struct drm_buf_entry *))
   1355 {
   1356 	struct drm_device_dma *dma = dev->dma;
   1357 	int i;
   1358 	int count;
   1359 
   1360 	if (!drm_core_check_feature(dev, DRIVER_LEGACY))
   1361 		return -EOPNOTSUPP;
   1362 
   1363 	if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA))
   1364 		return -EOPNOTSUPP;
   1365 
   1366 	if (!dma)
   1367 		return -EINVAL;
   1368 
   1369 	spin_lock(&dev->buf_lock);
   1370 	if (atomic_read(&dev->buf_alloc)) {
   1371 		spin_unlock(&dev->buf_lock);
   1372 		return -EBUSY;
   1373 	}
   1374 	++dev->buf_use;		/* Can't allocate more after this call */
   1375 	spin_unlock(&dev->buf_lock);
   1376 
   1377 	for (i = 0, count = 0; i < DRM_MAX_ORDER + 1; i++) {
   1378 		if (dma->bufs[i].buf_count)
   1379 			++count;
   1380 	}
   1381 
   1382 	DRM_DEBUG("count = %d\n", count);
   1383 
   1384 	if (*p >= count) {
   1385 		for (i = 0, count = 0; i < DRM_MAX_ORDER + 1; i++) {
   1386 			struct drm_buf_entry *from = &dma->bufs[i];
   1387 			if (from->buf_count) {
   1388 				if (f(data, count, from) < 0)
   1389 					return -EFAULT;
   1390 				DRM_DEBUG("%d %d %d %d %d\n",
   1391 					  i,
   1392 					  dma->bufs[i].buf_count,
   1393 					  dma->bufs[i].buf_size,
   1394 					  dma->bufs[i].low_mark,
   1395 					  dma->bufs[i].high_mark);
   1396 				++count;
   1397 			}
   1398 		}
   1399 	}
   1400 	*p = count;
   1401 
   1402 	return 0;
   1403 }
   1404 
   1405 static int copy_one_buf(void *data, int count, struct drm_buf_entry *from)
   1406 {
   1407 	struct drm_buf_info *request = data;
   1408 	struct drm_buf_desc __user *to = &request->list[count];
   1409 	struct drm_buf_desc v = {.count = from->buf_count,
   1410 				 .size = from->buf_size,
   1411 				 .low_mark = from->low_mark,
   1412 				 .high_mark = from->high_mark};
   1413 
   1414 	if (copy_to_user(to, &v, offsetof(struct drm_buf_desc, flags)))
   1415 		return -EFAULT;
   1416 	return 0;
   1417 }
   1418 
   1419 int drm_legacy_infobufs(struct drm_device *dev, void *data,
   1420 			struct drm_file *file_priv)
   1421 {
   1422 	struct drm_buf_info *request = data;
   1423 	return __drm_legacy_infobufs(dev, data, &request->count, copy_one_buf);
   1424 }
   1425 
   1426 /**
   1427  * Specifies a low and high water mark for buffer allocation
   1428  *
   1429  * \param inode device inode.
   1430  * \param file_priv DRM file private.
   1431  * \param cmd command.
   1432  * \param arg a pointer to a drm_buf_desc structure.
   1433  * \return zero on success or a negative number on failure.
   1434  *
   1435  * Verifies that the size order is bounded between the admissible orders and
   1436  * updates the respective drm_device_dma::bufs entry low and high water mark.
   1437  *
   1438  * \note This ioctl is deprecated and mostly never used.
   1439  */
   1440 int drm_legacy_markbufs(struct drm_device *dev, void *data,
   1441 			struct drm_file *file_priv)
   1442 {
   1443 	struct drm_device_dma *dma = dev->dma;
   1444 	struct drm_buf_desc *request = data;
   1445 	int order;
   1446 	struct drm_buf_entry *entry;
   1447 
   1448 	if (!drm_core_check_feature(dev, DRIVER_LEGACY))
   1449 		return -EOPNOTSUPP;
   1450 
   1451 	if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA))
   1452 		return -EOPNOTSUPP;
   1453 
   1454 	if (!dma)
   1455 		return -EINVAL;
   1456 
   1457 	DRM_DEBUG("%d, %d, %d\n",
   1458 		  request->size, request->low_mark, request->high_mark);
   1459 	order = order_base_2(request->size);
   1460 	if (order < DRM_MIN_ORDER || order > DRM_MAX_ORDER)
   1461 		return -EINVAL;
   1462 	entry = &dma->bufs[order];
   1463 
   1464 	if (request->low_mark < 0 || request->low_mark > entry->buf_count)
   1465 		return -EINVAL;
   1466 	if (request->high_mark < 0 || request->high_mark > entry->buf_count)
   1467 		return -EINVAL;
   1468 
   1469 	entry->low_mark = request->low_mark;
   1470 	entry->high_mark = request->high_mark;
   1471 
   1472 	return 0;
   1473 }
   1474 
   1475 /**
   1476  * Unreserve the buffers in list, previously reserved using drmDMA.
   1477  *
   1478  * \param inode device inode.
   1479  * \param file_priv DRM file private.
   1480  * \param cmd command.
   1481  * \param arg pointer to a drm_buf_free structure.
   1482  * \return zero on success or a negative number on failure.
   1483  *
   1484  * Calls free_buffer() for each used buffer.
   1485  * This function is primarily used for debugging.
   1486  */
   1487 int drm_legacy_freebufs(struct drm_device *dev, void *data,
   1488 			struct drm_file *file_priv)
   1489 {
   1490 	struct drm_device_dma *dma = dev->dma;
   1491 	struct drm_buf_free *request = data;
   1492 	int i;
   1493 	int idx;
   1494 	struct drm_buf *buf;
   1495 
   1496 	if (!drm_core_check_feature(dev, DRIVER_LEGACY))
   1497 		return -EOPNOTSUPP;
   1498 
   1499 	if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA))
   1500 		return -EOPNOTSUPP;
   1501 
   1502 	if (!dma)
   1503 		return -EINVAL;
   1504 
   1505 	DRM_DEBUG("%d\n", request->count);
   1506 	for (i = 0; i < request->count; i++) {
   1507 		if (copy_from_user(&idx, &request->list[i], sizeof(idx)))
   1508 			return -EFAULT;
   1509 		if (idx < 0 || idx >= dma->buf_count) {
   1510 			DRM_ERROR("Index %d (of %d max)\n",
   1511 				  idx, dma->buf_count - 1);
   1512 			return -EINVAL;
   1513 		}
   1514 		idx = array_index_nospec(idx, dma->buf_count);
   1515 		buf = dma->buflist[idx];
   1516 		if (buf->file_priv != file_priv) {
   1517 #ifdef __NetBSD__
   1518 			DRM_ERROR("Process %d freeing buffer not owned\n",
   1519 				  (int)curproc->p_pid);
   1520 #else
   1521 			DRM_ERROR("Process %d freeing buffer not owned\n",
   1522 				  task_pid_nr(current));
   1523 #endif
   1524 			return -EINVAL;
   1525 		}
   1526 		drm_legacy_free_buffer(dev, buf);
   1527 	}
   1528 
   1529 	return 0;
   1530 }
   1531 
   1532 /**
   1533  * Maps all of the DMA buffers into client-virtual space (ioctl).
   1534  *
   1535  * \param inode device inode.
   1536  * \param file_priv DRM file private.
   1537  * \param cmd command.
   1538  * \param arg pointer to a drm_buf_map structure.
   1539  * \return zero on success or a negative number on failure.
   1540  *
   1541  * Maps the AGP, SG or PCI buffer region with vm_mmap(), and copies information
   1542  * about each buffer into user space. For PCI buffers, it calls vm_mmap() with
   1543  * offset equal to 0, which drm_mmap() interpretes as PCI buffers and calls
   1544  * drm_mmap_dma().
   1545  */
   1546 int __drm_legacy_mapbufs(struct drm_device *dev, void *data, int *p,
   1547 			 void __user **v,
   1548 			 int (*f)(void *, int, unsigned long,
   1549 				 struct drm_buf *),
   1550 				 struct drm_file *file_priv)
   1551 {
   1552 	struct drm_device_dma *dma = dev->dma;
   1553 	int retcode = 0;
   1554 	unsigned long virtual;
   1555 	int i;
   1556 
   1557 	if (!drm_core_check_feature(dev, DRIVER_LEGACY))
   1558 		return -EOPNOTSUPP;
   1559 
   1560 	if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA))
   1561 		return -EOPNOTSUPP;
   1562 
   1563 	if (!dma)
   1564 		return -EINVAL;
   1565 
   1566 	spin_lock(&dev->buf_lock);
   1567 	if (atomic_read(&dev->buf_alloc)) {
   1568 		spin_unlock(&dev->buf_lock);
   1569 		return -EBUSY;
   1570 	}
   1571 	dev->buf_use++;		/* Can't allocate more after this call */
   1572 	spin_unlock(&dev->buf_lock);
   1573 
   1574 	if (*p >= dma->buf_count) {
   1575 		if ((dev->agp && (dma->flags & _DRM_DMA_USE_AGP))
   1576 		    || (drm_core_check_feature(dev, DRIVER_SG)
   1577 			&& (dma->flags & _DRM_DMA_USE_SG))) {
   1578 			struct drm_local_map *map = dev->agp_buffer_map;
   1579 			unsigned long token = dev->agp_buffer_token;
   1580 
   1581 			if (!map) {
   1582 				retcode = -EINVAL;
   1583 				goto done;
   1584 			}
   1585 			virtual = vm_mmap(file_priv->filp, 0, map->size,
   1586 					  PROT_READ | PROT_WRITE,
   1587 					  MAP_SHARED,
   1588 					  token);
   1589 		} else {
   1590 			virtual = vm_mmap(file_priv->filp, 0, dma->byte_count,
   1591 					  PROT_READ | PROT_WRITE,
   1592 					  MAP_SHARED, 0);
   1593 		}
   1594 		if (virtual > -1024UL) {
   1595 			/* Real error */
   1596 			retcode = (signed long)virtual;
   1597 			goto done;
   1598 		}
   1599 		*v = (void __user *)virtual;
   1600 
   1601 		for (i = 0; i < dma->buf_count; i++) {
   1602 			if (f(data, i, virtual, dma->buflist[i]) < 0) {
   1603 				retcode = -EFAULT;
   1604 				goto done;
   1605 			}
   1606 		}
   1607 	}
   1608       done:
   1609 	*p = dma->buf_count;
   1610 	DRM_DEBUG("%d buffers, retcode = %d\n", *p, retcode);
   1611 
   1612 	return retcode;
   1613 }
   1614 
   1615 static int map_one_buf(void *data, int idx, unsigned long virtual,
   1616 			struct drm_buf *buf)
   1617 {
   1618 	struct drm_buf_map *request = data;
   1619 	unsigned long address = virtual + buf->offset;	/* *** */
   1620 
   1621 	if (copy_to_user(&request->list[idx].idx, &buf->idx,
   1622 			 sizeof(request->list[0].idx)))
   1623 		return -EFAULT;
   1624 	if (copy_to_user(&request->list[idx].total, &buf->total,
   1625 			 sizeof(request->list[0].total)))
   1626 		return -EFAULT;
   1627 	if (clear_user(&request->list[idx].used, sizeof(int)))
   1628 		return -EFAULT;
   1629 	if (copy_to_user(&request->list[idx].address, &address,
   1630 			 sizeof(address)))
   1631 		return -EFAULT;
   1632 	return 0;
   1633 }
   1634 
   1635 int drm_legacy_mapbufs(struct drm_device *dev, void *data,
   1636 		       struct drm_file *file_priv)
   1637 {
   1638 	struct drm_buf_map *request = data;
   1639 	return __drm_legacy_mapbufs(dev, data, &request->count,
   1640 				    &request->virtual, map_one_buf,
   1641 				    file_priv);
   1642 }
   1643 
   1644 int drm_legacy_dma_ioctl(struct drm_device *dev, void *data,
   1645 		  struct drm_file *file_priv)
   1646 {
   1647 	if (!drm_core_check_feature(dev, DRIVER_LEGACY))
   1648 		return -EOPNOTSUPP;
   1649 
   1650 	if (dev->driver->dma_ioctl)
   1651 		return dev->driver->dma_ioctl(dev, data, file_priv);
   1652 	else
   1653 		return -EINVAL;
   1654 }
   1655 
   1656 struct drm_local_map *drm_legacy_getsarea(struct drm_device *dev)
   1657 {
   1658 	struct drm_map_list *entry;
   1659 
   1660 	list_for_each_entry(entry, &dev->maplist, head) {
   1661 		if (entry->map && entry->map->type == _DRM_SHM &&
   1662 		    (entry->map->flags & _DRM_CONTAINS_LOCK)) {
   1663 			return entry->map;
   1664 		}
   1665 	}
   1666 	return NULL;
   1667 }
   1668 EXPORT_SYMBOL(drm_legacy_getsarea);
   1669