drivers/char/drm/drm_memory.c

   1 /**
   2  * \file drm_memory.c
   3  * Memory management wrappers for DRM
   4  *
   5  * \author Rickard E. (Rik) Faith <faith@valinux.com>
   6  * \author Gareth Hughes <gareth@valinux.com>
   7  */
   8
   9 /*
  10  * Created: Thu Feb  4 14:00:34 1999 by faith@valinux.com
  11  *
  12  * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
  13  * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
  14  * All Rights Reserved.
  15  *
  16  * Permission is hereby granted, free of charge, to any person obtaining a
  17  * copy of this software and associated documentation files (the "Software"),
  18  * to deal in the Software without restriction, including without limitation
  19  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  20  * and/or sell copies of the Software, and to permit persons to whom the
  21  * Software is furnished to do so, subject to the following conditions:
  22  *
  23  * The above copyright notice and this permission notice (including the next
  24  * paragraph) shall be included in all copies or substantial portions of the
  25  * Software.
  26  *
  27  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  28  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  29  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  30  * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
  31  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  32  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  33  * OTHER DEALINGS IN THE SOFTWARE.
  34  */
  35
  36 #include <linux/highmem.h>
  37 #include "drmP.h"
  38
  39 #ifdef DEBUG_MEMORY
  40 #include "drm_memory_debug.h"
  41 #else
  42
  43 /** No-op. */
  44 void drm_mem_init(void)
  45 {
  46 }
  47
  48 /**
  49  * Called when "/proc/dri/%dev%/mem" is read.
  50  *
  51  * \param buf output buffer.
  52  * \param start start of output data.
  53  * \param offset requested start offset.
  54  * \param len requested number of bytes.
  55  * \param eof whether there is no more data to return.
  56  * \param data private data.
  57  * \return number of written bytes.
  58  *
  59  * No-op.
  60  */
  61 int drm_mem_info(char *buf, char **start, off_t offset,
  62                  int len, int *eof, void *data)
  63 {
  64         return 0;
  65 }
  66
  67 /** Wrapper around kmalloc() and kfree() */
  68 void *drm_realloc(void *oldpt, size_t oldsize, size_t size, int area)
  69 {
  70         void *pt;
  71
  72         if (!(pt = kmalloc(size, GFP_KERNEL)))
  73                 return NULL;
  74         if (oldpt && oldsize) {
  75                 memcpy(pt, oldpt, oldsize);
  76                 kfree(oldpt);
  77         }
  78         return pt;
  79 }
  80
  81 #if __OS_HAS_AGP
  82 static void *agp_remap(unsigned long offset, unsigned long size,
  83                        struct drm_device * dev)
  84 {
  85         unsigned long *phys_addr_map, i, num_pages =
  86             PAGE_ALIGN(size) / PAGE_SIZE;
  87         struct drm_agp_mem *agpmem;
  88         struct page **page_map;
  89         void *addr;
  90
  91         size = PAGE_ALIGN(size);
  92
  93 #ifdef __alpha__
  94         offset -= dev->hose->mem_space->start;
  95 #endif
  96
  97         list_for_each_entry(agpmem, &dev->agp->memory, head)
  98                 if (agpmem->bound <= offset
  99                     && (agpmem->bound + (agpmem->pages << PAGE_SHIFT)) >=
 100                     (offset + size))
 101                         break;
 102         if (!agpmem)
 103                 return NULL;
 104
 105         /*
 106          * OK, we're mapping AGP space on a chipset/platform on which memory accesses by
 107          * the CPU do not get remapped by the GART.  We fix this by using the kernel's
 108          * page-table instead (that's probably faster anyhow...).
 109          */
 110         /* note: use vmalloc() because num_pages could be large... */
 111         page_map = vmalloc(num_pages * sizeof(struct page *));
 112         if (!page_map)
 113                 return NULL;
 114
 115         phys_addr_map =
 116             agpmem->memory->memory + (offset - agpmem->bound) / PAGE_SIZE;
 117         for (i = 0; i < num_pages; ++i)
 118                 page_map[i] = pfn_to_page(phys_addr_map[i] >> PAGE_SHIFT);
 119         addr = vmap(page_map, num_pages, VM_IOREMAP, PAGE_AGP);
 120         vfree(page_map);
 121
 122         return addr;
 123 }
 124
 125 /** Wrapper around agp_allocate_memory() */
 126 DRM_AGP_MEM *drm_alloc_agp(struct drm_device * dev, int pages, u32 type)
 127 {
 128         return drm_agp_allocate_memory(dev->agp->bridge, pages, type);
 129 }
 130
 131 /** Wrapper around agp_free_memory() */
 132 int drm_free_agp(DRM_AGP_MEM * handle, int pages)
 133 {
 134         return drm_agp_free_memory(handle) ? 0 : -EINVAL;
 135 }
 136
 137 /** Wrapper around agp_bind_memory() */
 138 int drm_bind_agp(DRM_AGP_MEM * handle, unsigned int start)
 139 {
 140         return drm_agp_bind_memory(handle, start);
 141 }
 142
 143 /** Wrapper around agp_unbind_memory() */
 144 int drm_unbind_agp(DRM_AGP_MEM * handle)
 145 {
 146         return drm_agp_unbind_memory(handle);
 147 }
 148
 149 #else  /*  __OS_HAS_AGP  */
 150 static inline void *agp_remap(unsigned long offset, unsigned long size,
 151                               struct drm_device * dev)
 152 {
 153         return NULL;
 154 }
 155
 156 #endif                          /* agp */
 157
 158 #endif                          /* debug_memory */
 159
 160 void drm_core_ioremap(struct drm_map *map, struct drm_device *dev)
 161 {
 162         if (drm_core_has_AGP(dev) &&
 163             dev->agp && dev->agp->cant_use_aperture && map->type == _DRM_AGP)
 164                 map->handle = agp_remap(map->offset, map->size, dev);
 165         else
 166                 map->handle = ioremap(map->offset, map->size);
 167 }
 168 EXPORT_SYMBOL(drm_core_ioremap);
 169
 170 void drm_core_ioremapfree(struct drm_map *map, struct drm_device *dev)
 171 {
 172         if (!map->handle || !map->size)
 173                 return;
 174
 175         if (drm_core_has_AGP(dev) &&
 176             dev->agp && dev->agp->cant_use_aperture && map->type == _DRM_AGP)
 177                 vunmap(map->handle);
 178         else
 179                 iounmap(map->handle);
 180 }
 181 EXPORT_SYMBOL(drm_core_ioremapfree);
 182