usb-storage: redo incorrect reads
[zen-stable.git] / drivers / gpu / drm / drm_dma.c
blob252cbd74df0e6b862e07d340ba617cac165f1759
1 /**
2 * \file drm_dma.c
3 * DMA IOCTL and function support
5 * \author Rickard E. (Rik) Faith <faith@valinux.com>
6 * \author Gareth Hughes <gareth@valinux.com>
7 */
9 /*
10 * Created: Fri Mar 19 14:30:16 1999 by faith@valinux.com
12 * Copyright 1999, 2000 Precision Insight, Inc., Cedar Park, Texas.
13 * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
14 * All Rights Reserved.
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:
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.
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.
36 #include "drmP.h"
38 /**
39 * Initialize the DMA data.
41 * \param dev DRM device.
42 * \return zero on success or a negative value on failure.
44 * Allocate and initialize a drm_device_dma structure.
46 int drm_dma_setup(struct drm_device *dev)
48 int i;
50 dev->dma = kzalloc(sizeof(*dev->dma), GFP_KERNEL);
51 if (!dev->dma)
52 return -ENOMEM;
54 for (i = 0; i <= DRM_MAX_ORDER; i++)
55 memset(&dev->dma->bufs[i], 0, sizeof(dev->dma->bufs[0]));
57 return 0;
60 /**
61 * Cleanup the DMA resources.
63 * \param dev DRM device.
65 * Free all pages associated with DMA buffers, the buffers and pages lists, and
66 * finally the drm_device::dma structure itself.
68 void drm_dma_takedown(struct drm_device *dev)
70 struct drm_device_dma *dma = dev->dma;
71 int i, j;
73 if (!dma)
74 return;
76 /* Clear dma buffers */
77 for (i = 0; i <= DRM_MAX_ORDER; i++) {
78 if (dma->bufs[i].seg_count) {
79 DRM_DEBUG("order %d: buf_count = %d,"
80 " seg_count = %d\n",
82 dma->bufs[i].buf_count,
83 dma->bufs[i].seg_count);
84 for (j = 0; j < dma->bufs[i].seg_count; j++) {
85 if (dma->bufs[i].seglist[j]) {
86 drm_pci_free(dev, dma->bufs[i].seglist[j]);
89 kfree(dma->bufs[i].seglist);
91 if (dma->bufs[i].buf_count) {
92 for (j = 0; j < dma->bufs[i].buf_count; j++) {
93 kfree(dma->bufs[i].buflist[j].dev_private);
95 kfree(dma->bufs[i].buflist);
99 kfree(dma->buflist);
100 kfree(dma->pagelist);
101 kfree(dev->dma);
102 dev->dma = NULL;
106 * Free a buffer.
108 * \param dev DRM device.
109 * \param buf buffer to free.
111 * Resets the fields of \p buf.
113 void drm_free_buffer(struct drm_device *dev, struct drm_buf * buf)
115 if (!buf)
116 return;
118 buf->waiting = 0;
119 buf->pending = 0;
120 buf->file_priv = NULL;
121 buf->used = 0;
123 if (drm_core_check_feature(dev, DRIVER_DMA_QUEUE)
124 && waitqueue_active(&buf->dma_wait)) {
125 wake_up_interruptible(&buf->dma_wait);
130 * Reclaim the buffers.
132 * \param file_priv DRM file private.
134 * Frees each buffer associated with \p file_priv not already on the hardware.
136 void drm_core_reclaim_buffers(struct drm_device *dev,
137 struct drm_file *file_priv)
139 struct drm_device_dma *dma = dev->dma;
140 int i;
142 if (!dma)
143 return;
144 for (i = 0; i < dma->buf_count; i++) {
145 if (dma->buflist[i]->file_priv == file_priv) {
146 switch (dma->buflist[i]->list) {
147 case DRM_LIST_NONE:
148 drm_free_buffer(dev, dma->buflist[i]);
149 break;
150 case DRM_LIST_WAIT:
151 dma->buflist[i]->list = DRM_LIST_RECLAIM;
152 break;
153 default:
154 /* Buffer already on hardware. */
155 break;
161 EXPORT_SYMBOL(drm_core_reclaim_buffers);