sys/dev/drm/drm_dma.c

   1 /**
   2  * \file drm_dma.c
   3  * DMA IOCTL and function support
   4  *
   5  * \author Rickard E. (Rik) Faith <faith@valinux.com>
   6  * \author Gareth Hughes <gareth@valinux.com>
   7  */
   8
   9 /*
  10  * Created: Fri Mar 19 14:30:16 1999 by faith@valinux.com
  11  *
  12  * Copyright 1999, 2000 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/export.h>
  37 #include <drm/drmP.h>
  38 #include "drm_legacy.h"
  39
  40 /**
  41  * Initialize the DMA data.
  42  *
  43  * \param dev DRM device.
  44  * \return zero on success or a negative value on failure.
  45  *
  46  * Allocate and initialize a drm_device_dma structure.
  47  */
  48 int drm_legacy_dma_setup(struct drm_device *dev)
  49 {
  50         int i;
  51
  52         if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA) ||
  53             !drm_core_check_feature(dev, DRIVER_LEGACY))
  54                 return 0;
  55
  56         dev->buf_use = 0;
  57         atomic_set(&dev->buf_alloc, 0);
  58
  59         dev->dma = kzalloc(sizeof(*dev->dma), GFP_KERNEL);
  60         if (!dev->dma)
  61                 return -ENOMEM;
  62
  63         for (i = 0; i <= DRM_MAX_ORDER; i++)
  64                 memset(&dev->dma->bufs[i], 0, sizeof(dev->dma->bufs[0]));
  65
  66         return 0;
  67 }
  68
  69 /**
  70  * Cleanup the DMA resources.
  71  *
  72  * \param dev DRM device.
  73  *
  74  * Free all pages associated with DMA buffers, the buffers and pages lists, and
  75  * finally the drm_device::dma structure itself.
  76  */
  77 void drm_legacy_dma_takedown(struct drm_device *dev)
  78 {
  79         struct drm_device_dma *dma = dev->dma;
  80         int i, j;
  81
  82         if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA) ||
  83             !drm_core_check_feature(dev, DRIVER_LEGACY))
  84                 return;
  85
  86         if (!dma)
  87                 return;
  88
  89         /* Clear dma buffers */
  90         for (i = 0; i <= DRM_MAX_ORDER; i++) {
  91                 if (dma->bufs[i].seg_count) {
  92                         DRM_DEBUG("order %d: buf_count = %d,"
  93                                   " seg_count = %d\n",
  94                                   i,
  95                                   dma->bufs[i].buf_count,
  96                                   dma->bufs[i].seg_count);
  97                         for (j = 0; j < dma->bufs[i].seg_count; j++) {
  98                                 if (dma->bufs[i].seglist[j]) {
  99                                         drm_pci_free(dev, dma->bufs[i].seglist[j]);
 100                                 }
 101                         }
 102                         kfree(dma->bufs[i].seglist);
 103                 }
 104                 if (dma->bufs[i].buf_count) {
 105                         for (j = 0; j < dma->bufs[i].buf_count; j++) {
 106                                 kfree(dma->bufs[i].buflist[j].dev_private);
 107                         }
 108                         kfree(dma->bufs[i].buflist);
 109                 }
 110         }
 111
 112         kfree(dma->buflist);
 113         kfree(dma->pagelist);
 114         kfree(dev->dma);
 115         dev->dma = NULL;
 116 }
 117
 118 /**
 119  * Free a buffer.
 120  *
 121  * \param dev DRM device.
 122  * \param buf buffer to free.
 123  *
 124  * Resets the fields of \p buf.
 125  */
 126 void drm_legacy_free_buffer(struct drm_device *dev, struct drm_buf * buf)
 127 {
 128         if (!buf)
 129                 return;
 130
 131         buf->waiting = 0;
 132         buf->pending = 0;
 133         buf->file_priv = NULL;
 134         buf->used = 0;
 135 }
 136
 137 /**
 138  * Reclaim the buffers.
 139  *
 140  * \param file_priv DRM file private.
 141  *
 142  * Frees each buffer associated with \p file_priv not already on the hardware.
 143  */
 144 void drm_legacy_reclaim_buffers(struct drm_device *dev,
 145                                 struct drm_file *file_priv)
 146 {
 147         struct drm_device_dma *dma = dev->dma;
 148         int i;
 149
 150         if (!dma)
 151                 return;
 152         for (i = 0; i < dma->buf_count; i++) {
 153                 if (dma->buflist[i]->file_priv == file_priv) {
 154                         switch (dma->buflist[i]->list) {
 155                         case DRM_LIST_NONE:
 156                                 drm_legacy_free_buffer(dev, dma->buflist[i]);
 157                                 break;
 158                         case DRM_LIST_WAIT:
 159                                 dma->buflist[i]->list = DRM_LIST_RECLAIM;
 160                                 break;
 161                         default:
 162                                 /* Buffer already on hardware. */
 163                                 break;
 164                         }
 165                 }
 166         }
 167 }