swh:1:snp:32555a3fd8878f019c2ebd6c964bc1edcaeff337
Tip revision: 7d194c2100ad2a6dded545887d02754948ca5241 authored by Linus Torvalds on 20 October 2019, 19:56:22 UTC
Linux 5.4-rc4
Linux 5.4-rc4
Tip revision: 7d194c2
drm_memory.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/export.h>
#include <linux/highmem.h>
#include <linux/pci.h>
#include <linux/vmalloc.h>
#include <xen/xen.h>
#include <drm/drm_agpsupport.h>
#include <drm/drm_device.h>
#include "drm_legacy.h"
#if IS_ENABLED(CONFIG_AGP)
#ifdef HAVE_PAGE_AGP
# include <asm/agp.h>
#else
# ifdef __powerpc__
# define PAGE_AGP pgprot_noncached_wc(PAGE_KERNEL)
# else
# define PAGE_AGP PAGE_KERNEL
# endif
#endif
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(array_size(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_free_memory() */
void drm_free_agp(struct agp_memory *handle, int pages)
{
agp_free_memory(handle);
}
/** Wrapper around agp_bind_memory() */
int drm_bind_agp(struct agp_memory *handle, unsigned int start)
{
return agp_bind_memory(handle, start);
}
/** Wrapper around agp_unbind_memory() */
int drm_unbind_agp(struct agp_memory *handle)
{
return agp_unbind_memory(handle);
}
#else /* CONFIG_AGP */
static inline void *agp_remap(unsigned long offset, unsigned long size,
struct drm_device *dev)
{
return NULL;
}
#endif /* CONFIG_AGP */
void drm_legacy_ioremap(struct drm_local_map *map, struct drm_device *dev)
{
if (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_legacy_ioremap);
void drm_legacy_ioremap_wc(struct drm_local_map *map, struct drm_device *dev)
{
if (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_legacy_ioremap_wc);
void drm_legacy_ioremapfree(struct drm_local_map *map, struct drm_device *dev)
{
if (!map->handle || !map->size)
return;
if (dev->agp && dev->agp->cant_use_aperture && map->type == _DRM_AGP)
vunmap(map->handle);
else
iounmap(map->handle);
}
EXPORT_SYMBOL(drm_legacy_ioremapfree);
bool drm_need_swiotlb(int dma_bits)
{
struct resource *tmp;
resource_size_t max_iomem = 0;
/*
* Xen paravirtual hosts require swiotlb regardless of requested dma
* transfer size.
*
* NOTE: Really, what it requires is use of the dma_alloc_coherent
* allocator used in ttm_dma_populate() instead of
* ttm_populate_and_map_pages(), which bounce buffers so much in
* Xen it leads to swiotlb buffer exhaustion.
*/
if (xen_pv_domain())
return true;
/*
* Enforce dma_alloc_coherent when memory encryption is active as well
* for the same reasons as for Xen paravirtual hosts.
*/
if (mem_encrypt_active())
return true;
for (tmp = iomem_resource.child; tmp; tmp = tmp->sibling) {
max_iomem = max(max_iomem, tmp->end);
}
return max_iomem > ((u64)1 << dma_bits);
}
EXPORT_SYMBOL(drm_need_swiotlb);