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
  51         if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA) ||
  52             drm_core_check_feature(dev, DRIVER_MODESET)) {
  53                 return 0;
  54         }
  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         spin_init(&dev->dma_lock, "drmdma_lock");
  64
  65         return 0;
  66 }
  67
  68 /**
  69  * Cleanup the DMA resources.
  70  *
  71  * \param dev DRM device.
  72  *
  73  * Free all pages associated with DMA buffers, the buffers and pages lists, and
  74  * finally the drm_device::dma structure itself.
  75  */
  76 void drm_legacy_dma_takedown(struct drm_device *dev)
  77 {
  78         struct drm_device_dma *dma = dev->dma;
  79         int i, j;
  80
  81         if (dma == NULL)
  82                 return;
  83
  84         /* Clear dma buffers */
  85         for (i = 0; i <= DRM_MAX_ORDER; i++) {
  86                 if (dma->bufs[i].seg_count) {
  87                         DRM_DEBUG("order %d: buf_count = %d,"
  88                             " seg_count = %d\n", i, dma->bufs[i].buf_count,
  89                             dma->bufs[i].seg_count);
  90                         for (j = 0; j < dma->bufs[i].seg_count; j++) {
  91                                 drm_pci_free(dev, dma->bufs[i].seglist[j]);
  92                         }
  93                         kfree(dma->bufs[i].seglist);
  94                 }
  95                 if (dma->bufs[i].buf_count) {
  96                         for (j = 0; j < dma->bufs[i].buf_count; j++) {
  97                                 kfree(dma->bufs[i].buflist[j].dev_private);
  98                         }
  99                         kfree(dma->bufs[i].buflist);
 100                 }
 101         }
 102
 103         kfree(dma->buflist);
 104         kfree(dma->pagelist);
 105         kfree(dev->dma);
 106         dev->dma = NULL;
 107         spin_uninit(&dev->dma_lock);
 108 }
 109
 110 /**
 111  * Free a buffer.
 112  *
 113  * \param dev DRM device.
 114  * \param buf buffer to free.
 115  *
 116  * Resets the fields of \p buf.
 117  */
 118 void drm_legacy_free_buffer(struct drm_device *dev, struct drm_buf * buf)
 119 {
 120         if (!buf)
 121                 return;
 122
 123         buf->pending = 0;
 124         buf->file_priv = NULL;
 125         buf->used = 0;
 126 }
 127
 128 /**
 129  * Reclaim the buffers.
 130  *
 131  * \param file_priv DRM file private.
 132  *
 133  * Frees each buffer associated with \p file_priv not already on the hardware.
 134  */
 135 void drm_legacy_reclaim_buffers(struct drm_device *dev,
 136                                 struct drm_file *file_priv)
 137 {
 138         struct drm_device_dma *dma = dev->dma;
 139         int i;
 140
 141         if (!dma)
 142                 return;
 143         for (i = 0; i < dma->buf_count; i++) {
 144                 if (dma->buflist[i]->file_priv == file_priv) {
 145                         switch (dma->buflist[i]->list) {
 146                         case DRM_LIST_NONE:
 147                                 drm_legacy_free_buffer(dev, dma->buflist[i]);
 148                                 break;
 149                         case DRM_LIST_WAIT:
 150                                 dma->buflist[i]->list = DRM_LIST_RECLAIM;
 151                                 break;
 152                         default:
 153                                 /* Buffer already on hardware. */
 154                                 break;
 155                         }
 156                 }
 157         }
 158 }