drivers/char/drm/drm_pci.c

   1 /* drm_pci.h -- PCI DMA memory management wrappers for DRM -*- linux-c -*- */
   2 /**
   3  * \file drm_pci.c
   4  * \brief Functions and ioctls to manage PCI memory
   5  *
   6  * \warning These interfaces aren't stable yet.
   7  *
   8  * \todo Implement the remaining ioctl's for the PCI pools.
   9  * \todo The wrappers here are so thin that they would be better off inlined..
  10  *
  11  * \author Jose Fonseca <jrfonseca@tungstengraphics.com>
  12  * \author Leif Delgass <ldelgass@retinalburn.net>
  13  */
  14
  15 /*
  16  * Copyright 2003 Jos�Fonseca.
  17  * Copyright 2003 Leif Delgass.
  18  * All Rights Reserved.
  19  *
  20  * Permission is hereby granted, free of charge, to any person obtaining a
  21  * copy of this software and associated documentation files (the "Software"),
  22  * to deal in the Software without restriction, including without limitation
  23  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  24  * and/or sell copies of the Software, and to permit persons to whom the
  25  * Software is furnished to do so, subject to the following conditions:
  26  *
  27  * The above copyright notice and this permission notice (including the next
  28  * paragraph) shall be included in all copies or substantial portions of the
  29  * Software.
  30  *
  31  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  32  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  33  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
  34  * AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  35  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  36  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  37  */
  38
  39 #include <linux/pci.h>
  40 #include "drmP.h"
  41
  42 /**********************************************************************/
  43 /** \name PCI memory */
  44 /*@{*/
  45
  46 /**
  47  * \brief Allocate a PCI consistent memory block, for DMA.
  48  */
  49 void *drm_pci_alloc(drm_device_t * dev, size_t size, size_t align,
  50                     dma_addr_t maxaddr, dma_addr_t * busaddr)
  51 {
  52         void *address;
  53 #if DRM_DEBUG_MEMORY
  54         int area = DRM_MEM_DMA;
  55
  56         spin_lock(&drm_mem_lock);
  57         if ((drm_ram_used >> PAGE_SHIFT)
  58             > (DRM_RAM_PERCENT * drm_ram_available) / 100) {
  59                 spin_unlock(&drm_mem_lock);
  60                 return 0;
  61         }
  62         spin_unlock(&drm_mem_lock);
  63 #endif
  64
  65         /* pci_alloc_consistent only guarantees alignment to the smallest
  66          * PAGE_SIZE order which is greater than or equal to the requested size.
  67          * Return NULL here for now to make sure nobody tries for larger alignment
  68          */
  69         if (align > size)
  70                 return NULL;
  71
  72         if (pci_set_dma_mask(dev->pdev, maxaddr) != 0) {
  73                 DRM_ERROR("Setting pci dma mask failed\n");
  74                 return NULL;
  75         }
  76
  77         address = pci_alloc_consistent(dev->pdev, size, busaddr);
  78
  79 #if DRM_DEBUG_MEMORY
  80         if (address == NULL) {
  81                 spin_lock(&drm_mem_lock);
  82                 ++drm_mem_stats[area].fail_count;
  83                 spin_unlock(&drm_mem_lock);
  84                 return NULL;
  85         }
  86
  87         spin_lock(&drm_mem_lock);
  88         ++drm_mem_stats[area].succeed_count;
  89         drm_mem_stats[area].bytes_allocated += size;
  90         drm_ram_used += size;
  91         spin_unlock(&drm_mem_lock);
  92 #else
  93         if (address == NULL)
  94                 return NULL;
  95 #endif
  96
  97         memset(address, 0, size);
  98
  99         return address;
 100 }
 101 EXPORT_SYMBOL(drm_pci_alloc);
 102
 103 /**
 104  * \brief Free a PCI consistent memory block.
 105  */
 106 void
 107 drm_pci_free(drm_device_t * dev, size_t size, void *vaddr, dma_addr_t busaddr)
 108 {
 109 #if DRM_DEBUG_MEMORY
 110         int area = DRM_MEM_DMA;
 111         int alloc_count;
 112         int free_count;
 113 #endif
 114
 115         if (!vaddr) {
 116 #if DRM_DEBUG_MEMORY
 117                 DRM_MEM_ERROR(area, "Attempt to free address 0\n");
 118 #endif
 119         } else {
 120                 pci_free_consistent(dev->pdev, size, vaddr, busaddr);
 121         }
 122
 123 #if DRM_DEBUG_MEMORY
 124         spin_lock(&drm_mem_lock);
 125         free_count = ++drm_mem_stats[area].free_count;
 126         alloc_count = drm_mem_stats[area].succeed_count;
 127         drm_mem_stats[area].bytes_freed += size;
 128         drm_ram_used -= size;
 129         spin_unlock(&drm_mem_lock);
 130         if (free_count > alloc_count) {
 131                 DRM_MEM_ERROR(area,
 132                               "Excess frees: %d frees, %d allocs\n",
 133                               free_count, alloc_count);
 134         }
 135 #endif
 136
 137 }
 138 EXPORT_SYMBOL(drm_pci_free);
 139
 140 /*@}*/