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linux/drivers/gpu/drm/drm_bufs.c

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/**
* \file drm_bufs.c
* Generic buffer template
*
* \author Rickard E. (Rik) Faith <faith@valinux.com>
* \author Gareth Hughes <gareth@valinux.com>
*/
/*
* Created: Thu Nov 23 03:10:50 2000 by gareth@valinux.com
*
* Copyright 1999, 2000 Precision Insight, Inc., Cedar Park, Texas.
* Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
* All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
* OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*/
#include <linux/vmalloc.h>
#include <linux/slab.h>
#include <linux/log2.h>
#include <linux/export.h>
#include <asm/shmparam.h>
#include "drmP.h"
static struct drm_map_list *drm_find_matching_map(struct drm_device *dev,
struct drm_local_map *map)
{
struct drm_map_list *entry;
list_for_each_entry(entry, &dev->maplist, head) {
/*
* Because the kernel-userspace ABI is fixed at a 32-bit offset
* while PCI resources may live above that, we only compare the
* lower 32 bits of the map offset for maps of type
* _DRM_FRAMEBUFFER or _DRM_REGISTERS.
* It is assumed that if a driver have more than one resource
* of each type, the lower 32 bits are different.
*/
if (!entry->map ||
map->type != entry->map->type ||
entry->master != dev->primary->master)
continue;
switch (map->type) {
case _DRM_SHM:
if (map->flags != _DRM_CONTAINS_LOCK)
break;
return entry;
case _DRM_REGISTERS:
case _DRM_FRAME_BUFFER:
if ((entry->map->offset & 0xffffffff) ==
(map->offset & 0xffffffff))
return entry;
default: /* Make gcc happy */
;
}
if (entry->map->offset == map->offset)
return entry;
}
return NULL;
}
static int drm_map_handle(struct drm_device *dev, struct drm_hash_item *hash,
unsigned long user_token, int hashed_handle, int shm)
{
int use_hashed_handle, shift;
unsigned long add;
#if (BITS_PER_LONG == 64)
use_hashed_handle = ((user_token & 0xFFFFFFFF00000000UL) || hashed_handle);
#elif (BITS_PER_LONG == 32)
use_hashed_handle = hashed_handle;
#else
#error Unsupported long size. Neither 64 nor 32 bits.
#endif
if (!use_hashed_handle) {
int ret;
hash->key = user_token >> PAGE_SHIFT;
ret = drm_ht_insert_item(&dev->map_hash, hash);
if (ret != -EINVAL)
return ret;
}
shift = 0;
add = DRM_MAP_HASH_OFFSET >> PAGE_SHIFT;
if (shm && (SHMLBA > PAGE_SIZE)) {
int bits = ilog2(SHMLBA >> PAGE_SHIFT) + 1;
/* For shared memory, we have to preserve the SHMLBA
* bits of the eventual vma->vm_pgoff value during
* mmap(). Otherwise we run into cache aliasing problems
* on some platforms. On these platforms, the pgoff of
* a mmap() request is used to pick a suitable virtual
* address for the mmap() region such that it will not
* cause cache aliasing problems.
*
* Therefore, make sure the SHMLBA relevant bits of the
* hash value we use are equal to those in the original
* kernel virtual address.
*/
shift = bits;
add |= ((user_token >> PAGE_SHIFT) & ((1UL << bits) - 1UL));
}
return drm_ht_just_insert_please(&dev->map_hash, hash,
user_token, 32 - PAGE_SHIFT - 3,
shift, add);
}
/**
* Core function to create a range of memory available for mapping by a
* non-root process.
*
* Adjusts the memory offset to its absolute value according to the mapping
* type. Adds the map to the map list drm_device::maplist. Adds MTRR's where
* applicable and if supported by the kernel.
*/
static int drm_addmap_core(struct drm_device * dev, resource_size_t offset,
unsigned int size, enum drm_map_type type,
enum drm_map_flags flags,
struct drm_map_list ** maplist)
{
struct drm_local_map *map;
struct drm_map_list *list;
drm_dma_handle_t *dmah;
unsigned long user_token;
int ret;
map = kmalloc(sizeof(*map), GFP_KERNEL);
if (!map)
return -ENOMEM;
map->offset = offset;
map->size = size;
map->flags = flags;
map->type = type;
/* Only allow shared memory to be removable since we only keep enough
* book keeping information about shared memory to allow for removal
* when processes fork.
*/
if ((map->flags & _DRM_REMOVABLE) && map->type != _DRM_SHM) {
kfree(map);
return -EINVAL;
}
DRM_DEBUG("offset = 0x%08llx, size = 0x%08lx, type = %d\n",
(unsigned long long)map->offset, map->size, map->type);
/* page-align _DRM_SHM maps. They are allocated here so there is no security
* hole created by that and it works around various broken drivers that use
* a non-aligned quantity to map the SAREA. --BenH
*/
if (map->type == _DRM_SHM)
map->size = PAGE_ALIGN(map->size);
if ((map->offset & (~(resource_size_t)PAGE_MASK)) || (map->size & (~PAGE_MASK))) {
kfree(map);
return -EINVAL;
}
map->mtrr = -1;
map->handle = NULL;
switch (map->type) {
case _DRM_REGISTERS:
case _DRM_FRAME_BUFFER:
#if !defined(__sparc__) && !defined(__alpha__) && !defined(__ia64__) && !defined(__powerpc64__) && !defined(__x86_64__) && !defined(__arm__)
if (map->offset + (map->size-1) < map->offset ||
map->offset < virt_to_phys(high_memory)) {
kfree(map);
return -EINVAL;
}
#endif
/* Some drivers preinitialize some maps, without the X Server
* needing to be aware of it. Therefore, we just return success
* when the server tries to create a duplicate map.
*/
list = drm_find_matching_map(dev, map);
if (list != NULL) {
if (list->map->size != map->size) {
DRM_DEBUG("Matching maps of type %d with "
"mismatched sizes, (%ld vs %ld)\n",
map->type, map->size,
list->map->size);
list->map->size = map->size;
}
kfree(map);
*maplist = list;
return 0;
}
if (drm_core_has_MTRR(dev)) {
if (map->type == _DRM_FRAME_BUFFER ||
(map->flags & _DRM_WRITE_COMBINING)) {
map->mtrr = mtrr_add(map->offset, map->size,
MTRR_TYPE_WRCOMB, 1);
}
}
if (map->type == _DRM_REGISTERS) {
map->handle = ioremap(map->offset, map->size);
if (!map->handle) {
kfree(map);
return -ENOMEM;
}
}
break;
case _DRM_SHM:
list = drm_find_matching_map(dev, map);
if (list != NULL) {
if(list->map->size != map->size) {
DRM_DEBUG("Matching maps of type %d with "
"mismatched sizes, (%ld vs %ld)\n",
map->type, map->size, list->map->size);
list->map->size = map->size;
}
kfree(map);
*maplist = list;
return 0;
}
map->handle = vmalloc_user(map->size);
DRM_DEBUG("%lu %d %p\n",
map->size, drm_order(map->size), map->handle);
if (!map->handle) {
kfree(map);
return -ENOMEM;
}
map->offset = (unsigned long)map->handle;
if (map->flags & _DRM_CONTAINS_LOCK) {
/* Prevent a 2nd X Server from creating a 2nd lock */
if (dev->primary->master->lock.hw_lock != NULL) {
vfree(map->handle);
kfree(map);
return -EBUSY;
}
dev->sigdata.lock = dev->primary->master->lock.hw_lock = map->handle; /* Pointer to lock */
}
break;
case _DRM_AGP: {
struct drm_agp_mem *entry;
int valid = 0;
if (!drm_core_has_AGP(dev)) {
kfree(map);
return -EINVAL;
}
#ifdef __alpha__
map->offset += dev->hose->mem_space->start;
#endif
/* In some cases (i810 driver), user space may have already
* added the AGP base itself, because dev->agp->base previously
* only got set during AGP enable. So, only add the base
* address if the map's offset isn't already within the
* aperture.
*/
if (map->offset < dev->agp->base ||
map->offset > dev->agp->base +
dev->agp->agp_info.aper_size * 1024 * 1024 - 1) {
map->offset += dev->agp->base;
}
map->mtrr = dev->agp->agp_mtrr; /* for getmap */
/* This assumes the DRM is in total control of AGP space.
* It's not always the case as AGP can be in the control
* of user space (i.e. i810 driver). So this loop will get
* skipped and we double check that dev->agp->memory is
* actually set as well as being invalid before EPERM'ing
*/
list_for_each_entry(entry, &dev->agp->memory, head) {
if ((map->offset >= entry->bound) &&
(map->offset + map->size <= entry->bound + entry->pages * PAGE_SIZE)) {
valid = 1;
break;
}
}
if (!list_empty(&dev->agp->memory) && !valid) {
kfree(map);
return -EPERM;
}
DRM_DEBUG("AGP offset = 0x%08llx, size = 0x%08lx\n",
(unsigned long long)map->offset, map->size);
break;
}
case _DRM_GEM:
DRM_ERROR("tried to addmap GEM object\n");
break;
case _DRM_SCATTER_GATHER:
if (!dev->sg) {
kfree(map);
return -EINVAL;
}
map->offset += (unsigned long)dev->sg->virtual;
break;
case _DRM_CONSISTENT:
/* dma_addr_t is 64bit on i386 with CONFIG_HIGHMEM64G,
* As we're limiting the address to 2^32-1 (or less),
* casting it down to 32 bits is no problem, but we
* need to point to a 64bit variable first. */
dmah = drm_pci_alloc(dev, map->size, map->size);
if (!dmah) {
kfree(map);
return -ENOMEM;
}
map->handle = dmah->vaddr;
map->offset = (unsigned long)dmah->busaddr;
kfree(dmah);
break;
default:
kfree(map);
return -EINVAL;
}
list = kzalloc(sizeof(*list), GFP_KERNEL);
if (!list) {
if (map->type == _DRM_REGISTERS)
iounmap(map->handle);
kfree(map);
return -EINVAL;
}
list->map = map;
mutex_lock(&dev->struct_mutex);
list_add(&list->head, &dev->maplist);
/* Assign a 32-bit handle */
/* We do it here so that dev->struct_mutex protects the increment */
user_token = (map->type == _DRM_SHM) ? (unsigned long)map->handle :
map->offset;
ret = drm_map_handle(dev, &list->hash, user_token, 0,
(map->type == _DRM_SHM));
if (ret) {
if (map->type == _DRM_REGISTERS)
iounmap(map->handle);
kfree(map);
kfree(list);
mutex_unlock(&dev->struct_mutex);
return ret;
}
list->user_token = list->hash.key << PAGE_SHIFT;
mutex_unlock(&dev->struct_mutex);
if (!(map->flags & _DRM_DRIVER))
list->master = dev->primary->master;
*maplist = list;
return 0;
}
int drm_addmap(struct drm_device * dev, resource_size_t offset,
unsigned int size, enum drm_map_type type,
enum drm_map_flags flags, struct drm_local_map ** map_ptr)
{
struct drm_map_list *list;
int rc;
rc = drm_addmap_core(dev, offset, size, type, flags, &list);
if (!rc)
*map_ptr = list->map;
return rc;
}
EXPORT_SYMBOL(drm_addmap);
/**
* Ioctl to specify a range of memory that is available for mapping by a
* non-root process.
*
* \param inode device inode.
* \param file_priv DRM file private.
* \param cmd command.
* \param arg pointer to a drm_map structure.
* \return zero on success or a negative value on error.
*
*/
int drm_addmap_ioctl(struct drm_device *dev, void *data,
struct drm_file *file_priv)
{
struct drm_map *map = data;
struct drm_map_list *maplist;
int err;
if (!(capable(CAP_SYS_ADMIN) || map->type == _DRM_AGP || map->type == _DRM_SHM))
return -EPERM;
err = drm_addmap_core(dev, map->offset, map->size, map->type,
map->flags, &maplist);
if (err)
return err;
/* avoid a warning on 64-bit, this casting isn't very nice, but the API is set so too late */
map->handle = (void *)(unsigned long)maplist->user_token;
return 0;
}
/**
* Remove a map private from list and deallocate resources if the mapping
* isn't in use.
*
* Searches the map on drm_device::maplist, removes it from the list, see if
* its being used, and free any associate resource (such as MTRR's) if it's not
* being on use.
*
* \sa drm_addmap
*/
int drm_rmmap_locked(struct drm_device *dev, struct drm_local_map *map)
{
struct drm_map_list *r_list = NULL, *list_t;
drm_dma_handle_t dmah;
int found = 0;
struct drm_master *master;
/* Find the list entry for the map and remove it */
list_for_each_entry_safe(r_list, list_t, &dev->maplist, head) {
if (r_list->map == map) {
master = r_list->master;
list_del(&r_list->head);
drm_ht_remove_key(&dev->map_hash,
r_list->user_token >> PAGE_SHIFT);
kfree(r_list);
found = 1;
break;
}
}
if (!found)
return -EINVAL;
switch (map->type) {
case _DRM_REGISTERS:
iounmap(map->handle);
/* FALLTHROUGH */
case _DRM_FRAME_BUFFER:
if (drm_core_has_MTRR(dev) && map->mtrr >= 0) {
int retcode;
retcode = mtrr_del(map->mtrr, map->offset, map->size);
DRM_DEBUG("mtrr_del=%d\n", retcode);
}
break;
case _DRM_SHM:
vfree(map->handle);
if (master) {
if (dev->sigdata.lock == master->lock.hw_lock)
dev->sigdata.lock = NULL;
master->lock.hw_lock = NULL; /* SHM removed */
master->lock.file_priv = NULL;
wake_up_interruptible_all(&master->lock.lock_queue);
}
break;
case _DRM_AGP:
case _DRM_SCATTER_GATHER:
break;
case _DRM_CONSISTENT:
dmah.vaddr = map->handle;
dmah.busaddr = map->offset;
dmah.size = map->size;
__drm_pci_free(dev, &dmah);
break;
case _DRM_GEM:
DRM_ERROR("tried to rmmap GEM object\n");
break;
}
kfree(map);
return 0;
}
EXPORT_SYMBOL(drm_rmmap_locked);
int drm_rmmap(struct drm_device *dev, struct drm_local_map *map)
{
int ret;
mutex_lock(&dev->struct_mutex);
ret = drm_rmmap_locked(dev, map);
mutex_unlock(&dev->struct_mutex);
return ret;
}
EXPORT_SYMBOL(drm_rmmap);
/* The rmmap ioctl appears to be unnecessary. All mappings are torn down on
* the last close of the device, and this is necessary for cleanup when things
* exit uncleanly. Therefore, having userland manually remove mappings seems
* like a pointless exercise since they're going away anyway.
*
* One use case might be after addmap is allowed for normal users for SHM and
* gets used by drivers that the server doesn't need to care about. This seems
* unlikely.
*
* \param inode device inode.
* \param file_priv DRM file private.
* \param cmd command.
* \param arg pointer to a struct drm_map structure.
* \return zero on success or a negative value on error.
*/
int drm_rmmap_ioctl(struct drm_device *dev, void *data,
struct drm_file *file_priv)
{
struct drm_map *request = data;
struct drm_local_map *map = NULL;
struct drm_map_list *r_list;
int ret;
mutex_lock(&dev->struct_mutex);
list_for_each_entry(r_list, &dev->maplist, head) {
if (r_list->map &&
r_list->user_token == (unsigned long)request->handle &&
r_list->map->flags & _DRM_REMOVABLE) {
map = r_list->map;
break;
}
}
/* List has wrapped around to the head pointer, or its empty we didn't
* find anything.
*/
if (list_empty(&dev->maplist) || !map) {
mutex_unlock(&dev->struct_mutex);
return -EINVAL;
}
/* Register and framebuffer maps are permanent */
if ((map->type == _DRM_REGISTERS) || (map->type == _DRM_FRAME_BUFFER)) {
mutex_unlock(&dev->struct_mutex);
return 0;
}
ret = drm_rmmap_locked(dev, map);
mutex_unlock(&dev->struct_mutex);
return ret;
}
/**
* Cleanup after an error on one of the addbufs() functions.
*
* \param dev DRM device.
* \param entry buffer entry where the error occurred.
*
* Frees any pages and buffers associated with the given entry.
*/
static void drm_cleanup_buf_error(struct drm_device * dev,
struct drm_buf_entry * entry)
{
int i;
if (entry->seg_count) {
for (i = 0; i < entry->seg_count; i++) {
if (entry->seglist[i]) {
drm_pci_free(dev, entry->seglist[i]);
}
}
kfree(entry->seglist);
entry->seg_count = 0;
}
if (entry->buf_count) {
for (i = 0; i < entry->buf_count; i++) {
kfree(entry->buflist[i].dev_private);
}
kfree(entry->buflist);
entry->buf_count = 0;
}
}
#if __OS_HAS_AGP
/**
* Add AGP buffers for DMA transfers.
*
* \param dev struct drm_device to which the buffers are to be added.
* \param request pointer to a struct drm_buf_desc describing the request.
* \return zero on success or a negative number on failure.
*
* After some sanity checks creates a drm_buf structure for each buffer and
* reallocates the buffer list of the same size order to accommodate the new
* buffers.
*/
int drm_addbufs_agp(struct drm_device * dev, struct drm_buf_desc * request)
{
struct drm_device_dma *dma = dev->dma;
struct drm_buf_entry *entry;
struct drm_agp_mem *agp_entry;
struct drm_buf *buf;
unsigned long offset;
unsigned long agp_offset;
int count;
int order;
int size;
int alignment;
int page_order;
int total;
int byte_count;
int i, valid;
struct drm_buf **temp_buflist;
if (!dma)
return -EINVAL;
count = request->count;
order = drm_order(request->size);
size = 1 << order;
alignment = (request->flags & _DRM_PAGE_ALIGN)
? PAGE_ALIGN(size) : size;
page_order = order - PAGE_SHIFT > 0 ? order - PAGE_SHIFT : 0;
total = PAGE_SIZE << page_order;
byte_count = 0;
agp_offset = dev->agp->base + request->agp_start;
DRM_DEBUG("count: %d\n", count);
DRM_DEBUG("order: %d\n", order);
DRM_DEBUG("size: %d\n", size);
DRM_DEBUG("agp_offset: %lx\n", agp_offset);
DRM_DEBUG("alignment: %d\n", alignment);
DRM_DEBUG("page_order: %d\n", page_order);
DRM_DEBUG("total: %d\n", total);
if (order < DRM_MIN_ORDER || order > DRM_MAX_ORDER)
return -EINVAL;
if (dev->queue_count)
return -EBUSY; /* Not while in use */
/* Make sure buffers are located in AGP memory that we own */
valid = 0;
list_for_each_entry(agp_entry, &dev->agp->memory, head) {
if ((agp_offset >= agp_entry->bound) &&
(agp_offset + total * count <= agp_entry->bound + agp_entry->pages * PAGE_SIZE)) {
valid = 1;
break;
}
}
if (!list_empty(&dev->agp->memory) && !valid) {
DRM_DEBUG("zone invalid\n");
return -EINVAL;
}
spin_lock(&dev->count_lock);
if (dev->buf_use) {
spin_unlock(&dev->count_lock);
return -EBUSY;
}
atomic_inc(&dev->buf_alloc);
spin_unlock(&dev->count_lock);
mutex_lock(&dev->struct_mutex);
entry = &dma->bufs[order];
if (entry->buf_count) {
mutex_unlock(&dev->struct_mutex);
atomic_dec(&dev->buf_alloc);
return -ENOMEM; /* May only call once for each order */
}
if (count < 0 || count > 4096) {
mutex_unlock(&dev->struct_mutex);
atomic_dec(&dev->buf_alloc);
return -EINVAL;
}
entry->buflist = kzalloc(count * sizeof(*entry->buflist), GFP_KERNEL);
if (!entry->buflist) {
mutex_unlock(&dev->struct_mutex);
atomic_dec(&dev->buf_alloc);
return -ENOMEM;
}
entry->buf_size = size;
entry->page_order = page_order;
offset = 0;
while (entry->buf_count < count) {
buf = &entry->buflist[entry->buf_count];
buf->idx = dma->buf_count + entry->buf_count;
buf->total = alignment;
buf->order = order;
buf->used = 0;
buf->offset = (dma->byte_count + offset);
buf->bus_address = agp_offset + offset;
buf->address = (void *)(agp_offset + offset);
buf->next = NULL;
buf->waiting = 0;
buf->pending = 0;
init_waitqueue_head(&buf->dma_wait);
buf->file_priv = NULL;
buf->dev_priv_size = dev->driver->dev_priv_size;
buf->dev_private = kzalloc(buf->dev_priv_size, GFP_KERNEL);
if (!buf->dev_private) {
/* Set count correctly so we free the proper amount. */
entry->buf_count = count;
drm_cleanup_buf_error(dev, entry);
mutex_unlock(&dev->struct_mutex);
atomic_dec(&dev->buf_alloc);
return -ENOMEM;
}
DRM_DEBUG("buffer %d @ %p\n", entry->buf_count, buf->address);
offset += alignment;
entry->buf_count++;
byte_count += PAGE_SIZE << page_order;
}
DRM_DEBUG("byte_count: %d\n", byte_count);
temp_buflist = krealloc(dma->buflist,
(dma->buf_count + entry->buf_count) *
sizeof(*dma->buflist), GFP_KERNEL);
if (!temp_buflist) {
/* Free the entry because it isn't valid */
drm_cleanup_buf_error(dev, entry);
mutex_unlock(&dev->struct_mutex);
atomic_dec(&dev->buf_alloc);
return -ENOMEM;
}
dma->buflist = temp_buflist;
for (i = 0; i < entry->buf_count; i++) {
dma->buflist[i + dma->buf_count] = &entry->buflist[i];
}
dma->buf_count += entry->buf_count;
dma->seg_count += entry->seg_count;
dma->page_count += byte_count >> PAGE_SHIFT;
dma->byte_count += byte_count;
DRM_DEBUG("dma->buf_count : %d\n", dma->buf_count);
DRM_DEBUG("entry->buf_count : %d\n", entry->buf_count);
mutex_unlock(&dev->struct_mutex);
request->count = entry->buf_count;
request->size = size;
dma->flags = _DRM_DMA_USE_AGP;
atomic_dec(&dev->buf_alloc);
return 0;
}
EXPORT_SYMBOL(drm_addbufs_agp);
#endif /* __OS_HAS_AGP */
int drm_addbufs_pci(struct drm_device * dev, struct drm_buf_desc * request)
{
struct drm_device_dma *dma = dev->dma;
int count;
int order;
int size;
int total;
int page_order;
struct drm_buf_entry *entry;
drm_dma_handle_t *dmah;
struct drm_buf *buf;
int alignment;
unsigned long offset;
int i;
int byte_count;
int page_count;
unsigned long *temp_pagelist;
struct drm_buf **temp_buflist;
if (!drm_core_check_feature(dev, DRIVER_PCI_DMA))
return -EINVAL;
if (!dma)
return -EINVAL;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
count = request->count;
order = drm_order(request->size);
size = 1 << order;
DRM_DEBUG("count=%d, size=%d (%d), order=%d, queue_count=%d\n",
request->count, request->size, size, order, dev->queue_count);
if (order < DRM_MIN_ORDER || order > DRM_MAX_ORDER)
return -EINVAL;
if (dev->queue_count)
return -EBUSY; /* Not while in use */
alignment = (request->flags & _DRM_PAGE_ALIGN)
? PAGE_ALIGN(size) : size;
page_order = order - PAGE_SHIFT > 0 ? order - PAGE_SHIFT : 0;
total = PAGE_SIZE << page_order;
spin_lock(&dev->count_lock);
if (dev->buf_use) {
spin_unlock(&dev->count_lock);
return -EBUSY;
}
atomic_inc(&dev->buf_alloc);
spin_unlock(&dev->count_lock);
mutex_lock(&dev->struct_mutex);
entry = &dma->bufs[order];
if (entry->buf_count) {
mutex_unlock(&dev->struct_mutex);
atomic_dec(&dev->buf_alloc);
return -ENOMEM; /* May only call once for each order */
}
if (count < 0 || count > 4096) {
mutex_unlock(&dev->struct_mutex);
atomic_dec(&dev->buf_alloc);
return -EINVAL;
}
entry->buflist = kzalloc(count * sizeof(*entry->buflist), GFP_KERNEL);
if (!entry->buflist) {
mutex_unlock(&dev->struct_mutex);
atomic_dec(&dev->buf_alloc);
return -ENOMEM;
}
entry->seglist = kzalloc(count * sizeof(*entry->seglist), GFP_KERNEL);
if (!entry->seglist) {
kfree(entry->buflist);
mutex_unlock(&dev->struct_mutex);
atomic_dec(&dev->buf_alloc);
return -ENOMEM;
}
/* Keep the original pagelist until we know all the allocations
* have succeeded
*/
temp_pagelist = kmalloc((dma->page_count + (count << page_order)) *
sizeof(*dma->pagelist), GFP_KERNEL);
if (!temp_pagelist) {
kfree(entry->buflist);
kfree(entry->seglist);
mutex_unlock(&dev->struct_mutex);
atomic_dec(&dev->buf_alloc);
return -ENOMEM;
}
memcpy(temp_pagelist,
dma->pagelist, dma->page_count * sizeof(*dma->pagelist));
DRM_DEBUG("pagelist: %d entries\n",
dma->page_count + (count << page_order));
entry->buf_size = size;
entry->page_order = page_order;
byte_count = 0;
page_count = 0;
while (entry->buf_count < count) {
dmah = drm_pci_alloc(dev, PAGE_SIZE << page_order, 0x1000);
if (!dmah) {
/* Set count correctly so we free the proper amount. */
entry->buf_count = count;
entry->seg_count = count;
drm_cleanup_buf_error(dev, entry);
kfree(temp_pagelist);
mutex_unlock(&dev->struct_mutex);
atomic_dec(&dev->buf_alloc);
return -ENOMEM;
}
entry->seglist[entry->seg_count++] = dmah;
for (i = 0; i < (1 << page_order); i++) {
DRM_DEBUG("page %d @ 0x%08lx\n",
dma->page_count + page_count,
(unsigned long)dmah->vaddr + PAGE_SIZE * i);
temp_pagelist[dma->page_count + page_count++]
= (unsigned long)dmah->vaddr + PAGE_SIZE * i;
}
for (offset = 0;
offset + size <= total && entry->buf_count < count;
offset += alignment, ++entry->buf_count) {
buf = &entry->buflist[entry->buf_count];
buf->idx = dma->buf_count + entry->buf_count;
buf->total = alignment;
buf->order = order;
buf->used = 0;
buf->offset = (dma->byte_count + byte_count + offset);
buf->address = (void *)(dmah->vaddr + offset);
buf->bus_address = dmah->busaddr + offset;
buf->next = NULL;
buf->waiting = 0;
buf->pending = 0;
init_waitqueue_head(&buf->dma_wait);
buf->file_priv = NULL;
buf->dev_priv_size = dev->driver->dev_priv_size;
buf->dev_private = kzalloc(buf->dev_priv_size,
GFP_KERNEL);
if (!buf->dev_private) {
/* Set count correctly so we free the proper amount. */
entry->buf_count = count;
entry->seg_count = count;
drm_cleanup_buf_error(dev, entry);
kfree(temp_pagelist);
mutex_unlock(&dev->struct_mutex);
atomic_dec(&dev->buf_alloc);
return -ENOMEM;
}
DRM_DEBUG("buffer %d @ %p\n",
entry->buf_count, buf->address);
}
byte_count += PAGE_SIZE << page_order;
}
temp_buflist = krealloc(dma->buflist,
(dma->buf_count + entry->buf_count) *
sizeof(*dma->buflist), GFP_KERNEL);
if (!temp_buflist) {
/* Free the entry because it isn't valid */
drm_cleanup_buf_error(dev, entry);
kfree(temp_pagelist);
mutex_unlock(&dev->struct_mutex);
atomic_dec(&dev->buf_alloc);
return -ENOMEM;
}
dma->buflist = temp_buflist;
for (i = 0; i < entry->buf_count; i++) {
dma->buflist[i + dma->buf_count] = &entry->buflist[i];
}
/* No allocations failed, so now we can replace the original pagelist
* with the new one.
*/
if (dma->page_count) {
kfree(dma->pagelist);
}
dma->pagelist = temp_pagelist;
dma->buf_count += entry->buf_count;
dma->seg_count += entry->seg_count;
dma->page_count += entry->seg_count << page_order;
dma->byte_count += PAGE_SIZE * (entry->seg_count << page_order);
mutex_unlock(&dev->struct_mutex);
request->count = entry->buf_count;
request->size = size;
if (request->flags & _DRM_PCI_BUFFER_RO)
dma->flags = _DRM_DMA_USE_PCI_RO;
atomic_dec(&dev->buf_alloc);
return 0;
}
EXPORT_SYMBOL(drm_addbufs_pci);
static int drm_addbufs_sg(struct drm_device * dev, struct drm_buf_desc * request)
{
struct drm_device_dma *dma = dev->dma;
struct drm_buf_entry *entry;
struct drm_buf *buf;
unsigned long offset;
unsigned long agp_offset;
int count;
int order;
int size;
int alignment;
int page_order;
int total;
int byte_count;
int i;
struct drm_buf **temp_buflist;
if (!drm_core_check_feature(dev, DRIVER_SG))
return -EINVAL;
if (!dma)
return -EINVAL;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
count = request->count;
order = drm_order(request->size);
size = 1 << order;
alignment = (request->flags & _DRM_PAGE_ALIGN)
? PAGE_ALIGN(size) : size;
page_order = order - PAGE_SHIFT > 0 ? order - PAGE_SHIFT : 0;
total = PAGE_SIZE << page_order;
byte_count = 0;
agp_offset = request->agp_start;
DRM_DEBUG("count: %d\n", count);
DRM_DEBUG("order: %d\n", order);
DRM_DEBUG("size: %d\n", size);
DRM_DEBUG("agp_offset: %lu\n", agp_offset);
DRM_DEBUG("alignment: %d\n", alignment);
DRM_DEBUG("page_order: %d\n", page_order);
DRM_DEBUG("total: %d\n", total);
if (order < DRM_MIN_ORDER || order > DRM_MAX_ORDER)
return -EINVAL;
if (dev->queue_count)
return -EBUSY; /* Not while in use */
spin_lock(&dev->count_lock);
if (dev->buf_use) {
spin_unlock(&dev->count_lock);
return -EBUSY;
}
atomic_inc(&dev->buf_alloc);
spin_unlock(&dev->count_lock);
mutex_lock(&dev->struct_mutex);
entry = &dma->bufs[order];
if (entry->buf_count) {
mutex_unlock(&dev->struct_mutex);
atomic_dec(&dev->buf_alloc);
return -ENOMEM; /* May only call once for each order */
}
if (count < 0 || count > 4096) {
mutex_unlock(&dev->struct_mutex);
atomic_dec(&dev->buf_alloc);
return -EINVAL;
}
entry->buflist = kzalloc(count * sizeof(*entry->buflist),
GFP_KERNEL);
if (!entry->buflist) {
mutex_unlock(&dev->struct_mutex);
atomic_dec(&dev->buf_alloc);
return -ENOMEM;
}
entry->buf_size = size;
entry->page_order = page_order;
offset = 0;
while (entry->buf_count < count) {
buf = &entry->buflist[entry->buf_count];
buf->idx = dma->buf_count + entry->buf_count;
buf->total = alignment;
buf->order = order;
buf->used = 0;
buf->offset = (dma->byte_count + offset);
buf->bus_address = agp_offset + offset;
buf->address = (void *)(agp_offset + offset
+ (unsigned long)dev->sg->virtual);
buf->next = NULL;
buf->waiting = 0;
buf->pending = 0;
init_waitqueue_head(&buf->dma_wait);
buf->file_priv = NULL;
buf->dev_priv_size = dev->driver->dev_priv_size;
buf->dev_private = kzalloc(buf->dev_priv_size, GFP_KERNEL);
if (!buf->dev_private) {
/* Set count correctly so we free the proper amount. */
entry->buf_count = count;
drm_cleanup_buf_error(dev, entry);
mutex_unlock(&dev->struct_mutex);
atomic_dec(&dev->buf_alloc);
return -ENOMEM;
}
DRM_DEBUG("buffer %d @ %p\n", entry->buf_count, buf->address);
offset += alignment;
entry->buf_count++;
byte_count += PAGE_SIZE << page_order;
}
DRM_DEBUG("byte_count: %d\n", byte_count);
temp_buflist = krealloc(dma->buflist,
(dma->buf_count + entry->buf_count) *
sizeof(*dma->buflist), GFP_KERNEL);
if (!temp_buflist) {
/* Free the entry because it isn't valid */
drm_cleanup_buf_error(dev, entry);
mutex_unlock(&dev->struct_mutex);
atomic_dec(&dev->buf_alloc);
return -ENOMEM;
}
dma->buflist = temp_buflist;
for (i = 0; i < entry->buf_count; i++) {
dma->buflist[i + dma->buf_count] = &entry->buflist[i];
}
dma->buf_count += entry->buf_count;
dma->seg_count += entry->seg_count;
dma->page_count += byte_count >> PAGE_SHIFT;
dma->byte_count += byte_count;
DRM_DEBUG("dma->buf_count : %d\n", dma->buf_count);
DRM_DEBUG("entry->buf_count : %d\n", entry->buf_count);
mutex_unlock(&dev->struct_mutex);
request->count = entry->buf_count;
request->size = size;
dma->flags = _DRM_DMA_USE_SG;
atomic_dec(&dev->buf_alloc);
return 0;
}
static int drm_addbufs_fb(struct drm_device * dev, struct drm_buf_desc * request)
{
struct drm_device_dma *dma = dev->dma;
struct drm_buf_entry *entry;
struct drm_buf *buf;
unsigned long offset;
unsigned long agp_offset;
int count;
int order;
int size;
int alignment;
int page_order;
int total;
int byte_count;
int i;
struct drm_buf **temp_buflist;
if (!drm_core_check_feature(dev, DRIVER_FB_DMA))
return -EINVAL;
if (!dma)
return -EINVAL;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
count = request->count;
order = drm_order(request->size);
size = 1 << order;
alignment = (request->flags & _DRM_PAGE_ALIGN)
? PAGE_ALIGN(size) : size;
page_order = order - PAGE_SHIFT > 0 ? order - PAGE_SHIFT : 0;
total = PAGE_SIZE << page_order;
byte_count = 0;
agp_offset = request->agp_start;
DRM_DEBUG("count: %d\n", count);
DRM_DEBUG("order: %d\n", order);
DRM_DEBUG("size: %d\n", size);
DRM_DEBUG("agp_offset: %lu\n", agp_offset);
DRM_DEBUG("alignment: %d\n", alignment);
DRM_DEBUG("page_order: %d\n", page_order);
DRM_DEBUG("total: %d\n", total);
if (order < DRM_MIN_ORDER || order > DRM_MAX_ORDER)
return -EINVAL;
if (dev->queue_count)
return -EBUSY; /* Not while in use */
spin_lock(&dev->count_lock);
if (dev->buf_use) {
spin_unlock(&dev->count_lock);
return -EBUSY;
}
atomic_inc(&dev->buf_alloc);
spin_unlock(&dev->count_lock);
mutex_lock(&dev->struct_mutex);
entry = &dma->bufs[order];
if (entry->buf_count) {
mutex_unlock(&dev->struct_mutex);
atomic_dec(&dev->buf_alloc);
return -ENOMEM; /* May only call once for each order */
}
if (count < 0 || count > 4096) {
mutex_unlock(&dev->struct_mutex);
atomic_dec(&dev->buf_alloc);
return -EINVAL;
}
entry->buflist = kzalloc(count * sizeof(*entry->buflist),
GFP_KERNEL);
if (!entry->buflist) {
mutex_unlock(&dev->struct_mutex);
atomic_dec(&dev->buf_alloc);
return -ENOMEM;
}
entry->buf_size = size;
entry->page_order = page_order;
offset = 0;
while (entry->buf_count < count) {
buf = &entry->buflist[entry->buf_count];
buf->idx = dma->buf_count + entry->buf_count;
buf->total = alignment;
buf->order = order;
buf->used = 0;
buf->offset = (dma->byte_count + offset);
buf->bus_address = agp_offset + offset;
buf->address = (void *)(agp_offset + offset);
buf->next = NULL;
buf->waiting = 0;
buf->pending = 0;
init_waitqueue_head(&buf->dma_wait);
buf->file_priv = NULL;
buf->dev_priv_size = dev->driver->dev_priv_size;
buf->dev_private = kzalloc(buf->dev_priv_size, GFP_KERNEL);
if (!buf->dev_private) {
/* Set count correctly so we free the proper amount. */
entry->buf_count = count;
drm_cleanup_buf_error(dev, entry);
mutex_unlock(&dev->struct_mutex);
atomic_dec(&dev->buf_alloc);
return -ENOMEM;
}
DRM_DEBUG("buffer %d @ %p\n", entry->buf_count, buf->address);
offset += alignment;
entry->buf_count++;
byte_count += PAGE_SIZE << page_order;
}
DRM_DEBUG("byte_count: %d\n", byte_count);
temp_buflist = krealloc(dma->buflist,
(dma->buf_count + entry->buf_count) *
sizeof(*dma->buflist), GFP_KERNEL);
if (!temp_buflist) {
/* Free the entry because it isn't valid */
drm_cleanup_buf_error(dev, entry);
mutex_unlock(&dev->struct_mutex);
atomic_dec(&dev->buf_alloc);
return -ENOMEM;
}
dma->buflist = temp_buflist;
for (i = 0; i < entry->buf_count; i++) {
dma->buflist[i + dma->buf_count] = &entry->buflist[i];
}
dma->buf_count += entry->buf_count;
dma->seg_count += entry->seg_count;
dma->page_count += byte_count >> PAGE_SHIFT;
dma->byte_count += byte_count;
DRM_DEBUG("dma->buf_count : %d\n", dma->buf_count);
DRM_DEBUG("entry->buf_count : %d\n", entry->buf_count);
mutex_unlock(&dev->struct_mutex);
request->count = entry->buf_count;
request->size = size;
dma->flags = _DRM_DMA_USE_FB;
atomic_dec(&dev->buf_alloc);
return 0;
}
/**
* Add buffers for DMA transfers (ioctl).
*
* \param inode device inode.
* \param file_priv DRM file private.
* \param cmd command.
* \param arg pointer to a struct drm_buf_desc request.
* \return zero on success or a negative number on failure.
*
* According with the memory type specified in drm_buf_desc::flags and the
* build options, it dispatches the call either to addbufs_agp(),
* addbufs_sg() or addbufs_pci() for AGP, scatter-gather or consistent
* PCI memory respectively.
*/
int drm_addbufs(struct drm_device *dev, void *data,
struct drm_file *file_priv)
{
struct drm_buf_desc *request = data;
int ret;
if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA))
return -EINVAL;
#if __OS_HAS_AGP
if (request->flags & _DRM_AGP_BUFFER)
ret = drm_addbufs_agp(dev, request);
else
#endif
if (request->flags & _DRM_SG_BUFFER)
ret = drm_addbufs_sg(dev, request);
else if (request->flags & _DRM_FB_BUFFER)
ret = drm_addbufs_fb(dev, request);
else
ret = drm_addbufs_pci(dev, request);
return ret;
}
/**
* Get information about the buffer mappings.
*
* This was originally mean for debugging purposes, or by a sophisticated
* client library to determine how best to use the available buffers (e.g.,
* large buffers can be used for image transfer).
*
* \param inode device inode.
* \param file_priv DRM file private.
* \param cmd command.
* \param arg pointer to a drm_buf_info structure.
* \return zero on success or a negative number on failure.
*
* Increments drm_device::buf_use while holding the drm_device::count_lock
* lock, preventing of allocating more buffers after this call. Information
* about each requested buffer is then copied into user space.
*/
int drm_infobufs(struct drm_device *dev, void *data,
struct drm_file *file_priv)
{
struct drm_device_dma *dma = dev->dma;
struct drm_buf_info *request = data;
int i;
int count;
if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA))
return -EINVAL;
if (!dma)
return -EINVAL;
spin_lock(&dev->count_lock);
if (atomic_read(&dev->buf_alloc)) {
spin_unlock(&dev->count_lock);
return -EBUSY;
}
++dev->buf_use; /* Can't allocate more after this call */
spin_unlock(&dev->count_lock);
for (i = 0, count = 0; i < DRM_MAX_ORDER + 1; i++) {
if (dma->bufs[i].buf_count)
++count;
}
DRM_DEBUG("count = %d\n", count);
if (request->count >= count) {
for (i = 0, count = 0; i < DRM_MAX_ORDER + 1; i++) {
if (dma->bufs[i].buf_count) {
struct drm_buf_desc __user *to =
&request->list[count];
struct drm_buf_entry *from = &dma->bufs[i];
struct drm_freelist *list = &dma->bufs[i].freelist;
if (copy_to_user(&to->count,
&from->buf_count,
sizeof(from->buf_count)) ||
copy_to_user(&to->size,
&from->buf_size,
sizeof(from->buf_size)) ||
copy_to_user(&to->low_mark,
&list->low_mark,
sizeof(list->low_mark)) ||
copy_to_user(&to->high_mark,
&list->high_mark,
sizeof(list->high_mark)))
return -EFAULT;
DRM_DEBUG("%d %d %d %d %d\n",
i,
dma->bufs[i].buf_count,
dma->bufs[i].buf_size,
dma->bufs[i].freelist.low_mark,
dma->bufs[i].freelist.high_mark);
++count;
}
}
}
request->count = count;
return 0;
}
/**
* Specifies a low and high water mark for buffer allocation
*
* \param inode device inode.
* \param file_priv DRM file private.
* \param cmd command.
* \param arg a pointer to a drm_buf_desc structure.
* \return zero on success or a negative number on failure.
*
* Verifies that the size order is bounded between the admissible orders and
* updates the respective drm_device_dma::bufs entry low and high water mark.
*
* \note This ioctl is deprecated and mostly never used.
*/
int drm_markbufs(struct drm_device *dev, void *data,
struct drm_file *file_priv)
{
struct drm_device_dma *dma = dev->dma;
struct drm_buf_desc *request = data;
int order;
struct drm_buf_entry *entry;
if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA))
return -EINVAL;
if (!dma)
return -EINVAL;
DRM_DEBUG("%d, %d, %d\n",
request->size, request->low_mark, request->high_mark);
order = drm_order(request->size);
if (order < DRM_MIN_ORDER || order > DRM_MAX_ORDER)
return -EINVAL;
entry = &dma->bufs[order];
if (request->low_mark < 0 || request->low_mark > entry->buf_count)
return -EINVAL;
if (request->high_mark < 0 || request->high_mark > entry->buf_count)
return -EINVAL;
entry->freelist.low_mark = request->low_mark;
entry->freelist.high_mark = request->high_mark;
return 0;
}
/**
* Unreserve the buffers in list, previously reserved using drmDMA.
*
* \param inode device inode.
* \param file_priv DRM file private.
* \param cmd command.
* \param arg pointer to a drm_buf_free structure.
* \return zero on success or a negative number on failure.
*
* Calls free_buffer() for each used buffer.
* This function is primarily used for debugging.
*/
int drm_freebufs(struct drm_device *dev, void *data,
struct drm_file *file_priv)
{
struct drm_device_dma *dma = dev->dma;
struct drm_buf_free *request = data;
int i;
int idx;
struct drm_buf *buf;
if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA))
return -EINVAL;
if (!dma)
return -EINVAL;
DRM_DEBUG("%d\n", request->count);
for (i = 0; i < request->count; i++) {
if (copy_from_user(&idx, &request->list[i], sizeof(idx)))
return -EFAULT;
if (idx < 0 || idx >= dma->buf_count) {
DRM_ERROR("Index %d (of %d max)\n",
idx, dma->buf_count - 1);
return -EINVAL;
}
buf = dma->buflist[idx];
if (buf->file_priv != file_priv) {
DRM_ERROR("Process %d freeing buffer not owned\n",
task_pid_nr(current));
return -EINVAL;
}
drm_free_buffer(dev, buf);
}
return 0;
}
/**
* Maps all of the DMA buffers into client-virtual space (ioctl).
*
* \param inode device inode.
* \param file_priv DRM file private.
* \param cmd command.
* \param arg pointer to a drm_buf_map structure.
* \return zero on success or a negative number on failure.
*
* Maps the AGP, SG or PCI buffer region with do_mmap(), and copies information
* about each buffer into user space. For PCI buffers, it calls do_mmap() with
* offset equal to 0, which drm_mmap() interpretes as PCI buffers and calls
* drm_mmap_dma().
*/
int drm_mapbufs(struct drm_device *dev, void *data,
struct drm_file *file_priv)
{
struct drm_device_dma *dma = dev->dma;
int retcode = 0;
const int zero = 0;
unsigned long virtual;
unsigned long address;
struct drm_buf_map *request = data;
int i;
if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA))
return -EINVAL;
if (!dma)
return -EINVAL;
spin_lock(&dev->count_lock);
if (atomic_read(&dev->buf_alloc)) {
spin_unlock(&dev->count_lock);
return -EBUSY;
}
dev->buf_use++; /* Can't allocate more after this call */
spin_unlock(&dev->count_lock);
if (request->count >= dma->buf_count) {
if ((drm_core_has_AGP(dev) && (dma->flags & _DRM_DMA_USE_AGP))
|| (drm_core_check_feature(dev, DRIVER_SG)
&& (dma->flags & _DRM_DMA_USE_SG))
|| (drm_core_check_feature(dev, DRIVER_FB_DMA)
&& (dma->flags & _DRM_DMA_USE_FB))) {
struct drm_local_map *map = dev->agp_buffer_map;
unsigned long token = dev->agp_buffer_token;
if (!map) {
retcode = -EINVAL;
goto done;
}
down_write(&current->mm->mmap_sem);
virtual = do_mmap(file_priv->filp, 0, map->size,
PROT_READ | PROT_WRITE,
MAP_SHARED,
token);
up_write(&current->mm->mmap_sem);
} else {
down_write(&current->mm->mmap_sem);
virtual = do_mmap(file_priv->filp, 0, dma->byte_count,
PROT_READ | PROT_WRITE,
MAP_SHARED, 0);
up_write(&current->mm->mmap_sem);
}
if (virtual > -1024UL) {
/* Real error */
retcode = (signed long)virtual;
goto done;
}
request->virtual = (void __user *)virtual;
for (i = 0; i < dma->buf_count; i++) {
if (copy_to_user(&request->list[i].idx,
&dma->buflist[i]->idx,
sizeof(request->list[0].idx))) {
retcode = -EFAULT;
goto done;
}
if (copy_to_user(&request->list[i].total,
&dma->buflist[i]->total,
sizeof(request->list[0].total))) {
retcode = -EFAULT;
goto done;
}
if (copy_to_user(&request->list[i].used,
&zero, sizeof(zero))) {
retcode = -EFAULT;
goto done;
}
address = virtual + dma->buflist[i]->offset; /* *** */
if (copy_to_user(&request->list[i].address,
&address, sizeof(address))) {
retcode = -EFAULT;
goto done;
}
}
}
done:
request->count = dma->buf_count;
DRM_DEBUG("%d buffers, retcode = %d\n", request->count, retcode);
return retcode;
}
/**
* Compute size order. Returns the exponent of the smaller power of two which
* is greater or equal to given number.
*
* \param size size.
* \return order.
*
* \todo Can be made faster.
*/
int drm_order(unsigned long size)
{
int order;
unsigned long tmp;
for (order = 0, tmp = size >> 1; tmp; tmp >>= 1, order++) ;
if (size & (size - 1))
++order;
return order;
}
EXPORT_SYMBOL(drm_order);
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