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 <linux/pci.h>
38 
39 #include <drm/drm_drv.h>
40 #include <drm/drm_print.h>
41 
42 #include "drm_legacy.h"
43 
44 /**
45  * drm_legacy_dma_setup() - Initialize the DMA data.
46  *
47  * @dev: DRM device.
48  * Return: zero on success or a negative value on failure.
49  *
50  * Allocate and initialize a drm_device_dma structure.
51  */
drm_legacy_dma_setup(struct drm_device * dev)52 int drm_legacy_dma_setup(struct drm_device *dev)
53 {
54 	int i;
55 
56 	if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA) ||
57 	    !drm_core_check_feature(dev, DRIVER_LEGACY))
58 		return 0;
59 
60 	dev->buf_use = 0;
61 	atomic_set(&dev->buf_alloc, 0);
62 
63 	dev->dma = kzalloc(sizeof(*dev->dma), GFP_KERNEL);
64 	if (!dev->dma)
65 		return -ENOMEM;
66 
67 	for (i = 0; i <= DRM_MAX_ORDER; i++)
68 		memset(&dev->dma->bufs[i], 0, sizeof(dev->dma->bufs[0]));
69 
70 	return 0;
71 }
72 
73 /**
74  * drm_legacy_dma_takedown() - Cleanup the DMA resources.
75  *
76  * @dev: DRM device.
77  *
78  * Free all pages associated with DMA buffers, the buffers and pages lists, and
79  * finally the drm_device::dma structure itself.
80  */
drm_legacy_dma_takedown(struct drm_device * dev)81 void drm_legacy_dma_takedown(struct drm_device *dev)
82 {
83 	struct drm_device_dma *dma = dev->dma;
84 	drm_dma_handle_t *dmah;
85 	int i, j;
86 
87 	if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA) ||
88 	    !drm_core_check_feature(dev, DRIVER_LEGACY))
89 		return;
90 
91 	if (!dma)
92 		return;
93 
94 	/* Clear dma buffers */
95 	for (i = 0; i <= DRM_MAX_ORDER; i++) {
96 		if (dma->bufs[i].seg_count) {
97 			DRM_DEBUG("order %d: buf_count = %d,"
98 				  " seg_count = %d\n",
99 				  i,
100 				  dma->bufs[i].buf_count,
101 				  dma->bufs[i].seg_count);
102 			for (j = 0; j < dma->bufs[i].seg_count; j++) {
103 				if (dma->bufs[i].seglist[j]) {
104 					dmah = dma->bufs[i].seglist[j];
105 					dma_free_coherent(dev->dev,
106 							  dmah->size,
107 							  dmah->vaddr,
108 							  dmah->busaddr);
109 					kfree(dmah);
110 				}
111 			}
112 			kfree(dma->bufs[i].seglist);
113 		}
114 		if (dma->bufs[i].buf_count) {
115 			for (j = 0; j < dma->bufs[i].buf_count; j++) {
116 				kfree(dma->bufs[i].buflist[j].dev_private);
117 			}
118 			kfree(dma->bufs[i].buflist);
119 		}
120 	}
121 
122 	kfree(dma->buflist);
123 	kfree(dma->pagelist);
124 	kfree(dev->dma);
125 	dev->dma = NULL;
126 }
127 
128 /**
129  * drm_legacy_free_buffer() - Free a buffer.
130  *
131  * @dev: DRM device.
132  * @buf: buffer to free.
133  *
134  * Resets the fields of \p buf.
135  */
drm_legacy_free_buffer(struct drm_device * dev,struct drm_buf * buf)136 void drm_legacy_free_buffer(struct drm_device *dev, struct drm_buf * buf)
137 {
138 	if (!buf)
139 		return;
140 
141 	buf->waiting = 0;
142 	buf->pending = 0;
143 	buf->file_priv = NULL;
144 	buf->used = 0;
145 }
146 
147 /**
148  * drm_legacy_reclaim_buffers() - Reclaim the buffers.
149  *
150  * @dev: DRM device.
151  * @file_priv: DRM file private.
152  *
153  * Frees each buffer associated with \p file_priv not already on the hardware.
154  */
drm_legacy_reclaim_buffers(struct drm_device * dev,struct drm_file * file_priv)155 void drm_legacy_reclaim_buffers(struct drm_device *dev,
156 				struct drm_file *file_priv)
157 {
158 	struct drm_device_dma *dma = dev->dma;
159 	int i;
160 
161 	if (!dma)
162 		return;
163 	for (i = 0; i < dma->buf_count; i++) {
164 		if (dma->buflist[i]->file_priv == file_priv) {
165 			switch (dma->buflist[i]->list) {
166 			case DRM_LIST_NONE:
167 				drm_legacy_free_buffer(dev, dma->buflist[i]);
168 				break;
169 			case DRM_LIST_WAIT:
170 				dma->buflist[i]->list = DRM_LIST_RECLAIM;
171 				break;
172 			default:
173 				/* Buffer already on hardware. */
174 				break;
175 			}
176 		}
177 	}
178 }
179