linux/drivers/gpu/drm/drm_memory.c
Dan Carpenter 404b017d00 drivers/gpu/drm/drm_memory.c: fix check for end of loop
"agpmem" is never NULL here.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Cc: Eric Anholt <eric@anholt.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-04-28 18:41:51 +10:00

169 lines
4.9 KiB
C

/**
* \file drm_memory.c
* Memory management wrappers for DRM
*
* \author Rickard E. (Rik) Faith <faith@valinux.com>
* \author Gareth Hughes <gareth@valinux.com>
*/
/*
* Created: Thu Feb 4 14:00:34 1999 by faith@valinux.com
*
* Copyright 1999 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/highmem.h>
#include "drmP.h"
/**
* Called when "/proc/dri/%dev%/mem" is read.
*
* \param buf output buffer.
* \param start start of output data.
* \param offset requested start offset.
* \param len requested number of bytes.
* \param eof whether there is no more data to return.
* \param data private data.
* \return number of written bytes.
*
* No-op.
*/
int drm_mem_info(char *buf, char **start, off_t offset,
int len, int *eof, void *data)
{
return 0;
}
#if __OS_HAS_AGP
static void *agp_remap(unsigned long offset, unsigned long size,
struct drm_device * dev)
{
unsigned long i, num_pages =
PAGE_ALIGN(size) / PAGE_SIZE;
struct drm_agp_mem *agpmem;
struct page **page_map;
struct page **phys_page_map;
void *addr;
size = PAGE_ALIGN(size);
#ifdef __alpha__
offset -= dev->hose->mem_space->start;
#endif
list_for_each_entry(agpmem, &dev->agp->memory, head)
if (agpmem->bound <= offset
&& (agpmem->bound + (agpmem->pages << PAGE_SHIFT)) >=
(offset + size))
break;
if (&agpmem->head == &dev->agp->memory)
return NULL;
/*
* OK, we're mapping AGP space on a chipset/platform on which memory accesses by
* the CPU do not get remapped by the GART. We fix this by using the kernel's
* page-table instead (that's probably faster anyhow...).
*/
/* note: use vmalloc() because num_pages could be large... */
page_map = vmalloc(num_pages * sizeof(struct page *));
if (!page_map)
return NULL;
phys_page_map = (agpmem->memory->pages + (offset - agpmem->bound) / PAGE_SIZE);
for (i = 0; i < num_pages; ++i)
page_map[i] = phys_page_map[i];
addr = vmap(page_map, num_pages, VM_IOREMAP, PAGE_AGP);
vfree(page_map);
return addr;
}
/** Wrapper around agp_allocate_memory() */
DRM_AGP_MEM *drm_alloc_agp(struct drm_device * dev, int pages, u32 type)
{
return drm_agp_allocate_memory(dev->agp->bridge, pages, type);
}
/** Wrapper around agp_free_memory() */
int drm_free_agp(DRM_AGP_MEM * handle, int pages)
{
return drm_agp_free_memory(handle) ? 0 : -EINVAL;
}
EXPORT_SYMBOL(drm_free_agp);
/** Wrapper around agp_bind_memory() */
int drm_bind_agp(DRM_AGP_MEM * handle, unsigned int start)
{
return drm_agp_bind_memory(handle, start);
}
/** Wrapper around agp_unbind_memory() */
int drm_unbind_agp(DRM_AGP_MEM * handle)
{
return drm_agp_unbind_memory(handle);
}
EXPORT_SYMBOL(drm_unbind_agp);
#else /* __OS_HAS_AGP */
static inline void *agp_remap(unsigned long offset, unsigned long size,
struct drm_device * dev)
{
return NULL;
}
#endif /* agp */
void drm_core_ioremap(struct drm_local_map *map, struct drm_device *dev)
{
if (drm_core_has_AGP(dev) &&
dev->agp && dev->agp->cant_use_aperture && map->type == _DRM_AGP)
map->handle = agp_remap(map->offset, map->size, dev);
else
map->handle = ioremap(map->offset, map->size);
}
EXPORT_SYMBOL(drm_core_ioremap);
void drm_core_ioremap_wc(struct drm_local_map *map, struct drm_device *dev)
{
if (drm_core_has_AGP(dev) &&
dev->agp && dev->agp->cant_use_aperture && map->type == _DRM_AGP)
map->handle = agp_remap(map->offset, map->size, dev);
else
map->handle = ioremap_wc(map->offset, map->size);
}
EXPORT_SYMBOL(drm_core_ioremap_wc);
void drm_core_ioremapfree(struct drm_local_map *map, struct drm_device *dev)
{
if (!map->handle || !map->size)
return;
if (drm_core_has_AGP(dev) &&
dev->agp && dev->agp->cant_use_aperture && map->type == _DRM_AGP)
vunmap(map->handle);
else
iounmap(map->handle);
}
EXPORT_SYMBOL(drm_core_ioremapfree);