summaryrefslogtreecommitdiff
path: root/linux-core/drm_context.c
blob: 6bbcfca8bd35fc430f90d9f917db5d3f7f855931 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
/* drm_context.h -- IOCTLs for generic contexts -*- linux-c -*-
 * Created: Fri Nov 24 18:31:37 2000 by gareth@valinux.com
 *
 * Copyright 1999, 2000 Precision Insight, Inc., Cedar Park, Texas.
 * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
 * All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 *
 * Authors:
 *    Rickard E. (Rik) Faith <faith@valinux.com>
 *    Gareth Hughes <gareth@valinux.com>
 */

/* ================================================================
 * Context bitmap support
 */

void DRM(ctxbitmap_free)( drm_device_t *dev, int ctx_handle )
{
	if ( ctx_handle < 0 ) goto failed;

	if ( ctx_handle < DRM_MAX_CTXBITMAP ) {
		clear_bit( ctx_handle, dev->ctx_bitmap );
		return;
	}
failed:
       	DRM_ERROR( "Attempt to free invalid context handle: %d\n",
		   ctx_handle );
       	return;
}

int DRM(ctxbitmap_next)( drm_device_t *dev )
{
	int bit;

	bit = find_first_zero_bit( dev->ctx_bitmap, DRM_MAX_CTXBITMAP );
	if ( bit < DRM_MAX_CTXBITMAP ) {
		set_bit( bit, dev->ctx_bitmap );
	   	DRM_DEBUG( "drm_ctxbitmap_next bit : %d\n", bit );
		return bit;
	}
	return -1;
}

int DRM(ctxbitmap_init)( drm_device_t *dev )
{
	int i;
   	int temp;

	dev->ctx_bitmap = (unsigned long *) DRM(alloc)( PAGE_SIZE,
							DRM_MEM_CTXBITMAP );
	if ( dev->ctx_bitmap == NULL ) {
		return -ENOMEM;
	}
	memset( (void *)dev->ctx_bitmap, 0, PAGE_SIZE );
	for ( i = 0 ; i < DRM_RESERVED_CONTEXTS ; i++ ) {
		temp = DRM(ctxbitmap_next)( dev );
	   	DRM_DEBUG( "drm_ctxbitmap_init : %d\n", temp );
	}

	return 0;
}

void DRM(ctxbitmap_cleanup)( drm_device_t *dev )
{
	DRM(free)( (void *)dev->ctx_bitmap, PAGE_SIZE, DRM_MEM_CTXBITMAP );
}


/* ================================================================
 * The actual DRM context handling routines
 */

int DRM(context_switch)( drm_device_t *dev, int old, int new )
{
        char buf[64];

        if ( test_and_set_bit( 0, &dev->context_flag ) ) {
                DRM_ERROR( "Reentering -- FIXME\n" );
                return -EBUSY;
        }

#if DRM_DMA_HISTOGRAM
        dev->ctx_start = get_cycles();
#endif

        DRM_DEBUG( "Context switch from %d to %d\n", old, new );

        if ( new == dev->last_context ) {
                clear_bit( 0, &dev->context_flag );
                return 0;
        }

        if ( DRM(flags) & DRM_FLAG_NOCTX ) {
                DRM(context_switch_complete)( dev, new );
        } else {
                sprintf( buf, "C %d %d\n", old, new );
                DRM(write_string)( dev, buf );
        }

        return 0;
}

int DRM(context_switch_complete)( drm_device_t *dev, int new )
{
        dev->last_context = new;  /* PRE/POST: This is the _only_ writer. */
        dev->last_switch  = jiffies;

        if ( !_DRM_LOCK_IS_HELD(dev->lock.hw_lock->lock) ) {
                DRM_ERROR( "Lock isn't held after context switch\n" );
        }

				/* If a context switch is ever initiated
                                   when the kernel holds the lock, release
                                   that lock here. */
#if DRM_DMA_HISTOGRAM
        atomic_inc( &dev->histo.ctx[DRM(histogram_slot)(get_cycles()
							- dev->ctx_start)] );

#endif
        clear_bit( 0, &dev->context_flag );
        wake_up( &dev->context_wait );

        return 0;
}

int DRM(resctx)( struct inode *inode, struct file *filp,
		 unsigned int cmd, unsigned long arg )
{
	drm_ctx_res_t res;
	drm_ctx_t ctx;
	int i;

	if ( copy_from_user( &res, (drm_ctx_res_t *)arg, sizeof(res) ) )
		return -EFAULT;

	if ( res.count >= DRM_RESERVED_CONTEXTS ) {
		memset( &ctx, 0, sizeof(ctx) );
		for ( i = 0 ; i < DRM_RESERVED_CONTEXTS ; i++ ) {
			ctx.handle = i;
			if ( copy_to_user( &res.contexts[i],
					   &i, sizeof(i) ) )
				return -EFAULT;
		}
	}
	res.count = DRM_RESERVED_CONTEXTS;

	if ( copy_to_user( (drm_ctx_res_t *)arg, &res, sizeof(res) ) )
		return -EFAULT;
	return 0;
}

int DRM(addctx)( struct inode *inode, struct file *filp,
		 unsigned int cmd, unsigned long arg )
{
	drm_file_t *priv = filp->private_data;
	drm_device_t *dev = priv->dev;
	drm_ctx_t ctx;

	if ( copy_from_user( &ctx, (drm_ctx_t *)arg, sizeof(ctx) ) )
		return -EFAULT;

	ctx.handle = DRM(ctxbitmap_next)( dev );
	if ( ctx.handle == DRM_KERNEL_CONTEXT ) {
				/* Skip kernel's context and get a new one. */
		ctx.handle = DRM(ctxbitmap_next)( dev );
	}
	DRM_DEBUG( "%d\n", ctx.handle );
	if ( ctx.handle == -1 ) {
		DRM_DEBUG( "Not enough free contexts.\n" );
				/* Should this return -EBUSY instead? */
		return -ENOMEM;
	}

	if ( copy_to_user( (drm_ctx_t *)arg, &ctx, sizeof(ctx) ) )
		return -EFAULT;
	return 0;
}

int DRM(modctx)( struct inode *inode, struct file *filp,
		 unsigned int cmd, unsigned long arg )
{
	/* This does nothing */
	return 0;
}

int DRM(getctx)( struct inode *inode, struct file *filp,
		 unsigned int cmd, unsigned long arg )
{
	drm_ctx_t ctx;

	if ( copy_from_user( &ctx, (drm_ctx_t*)arg, sizeof(ctx) ) )
		return -EFAULT;

	/* This is 0, because we don't handle any context flags */
	ctx.flags = 0;

	if ( copy_to_user( (drm_ctx_t*)arg, &ctx, sizeof(ctx) ) )
		return -EFAULT;
	return 0;
}

int DRM(switchctx)( struct inode *inode, struct file *filp,
		    unsigned int cmd, unsigned long arg )
{
	drm_file_t *priv = filp->private_data;
	drm_device_t *dev = priv->dev;
	drm_ctx_t ctx;

	if ( copy_from_user( &ctx, (drm_ctx_t *)arg, sizeof(ctx) ) )
		return -EFAULT;

	DRM_DEBUG( "%d\n", ctx.handle );
	return DRM(context_switch)( dev, dev->last_context, ctx.handle );
}

int DRM(newctx)( struct inode *inode, struct file *filp,
		 unsigned int cmd, unsigned long arg )
{
	drm_file_t *priv = filp->private_data;
	drm_device_t *dev = priv->dev;
	drm_ctx_t ctx;

	if ( copy_from_user( &ctx, (drm_ctx_t *)arg, sizeof(ctx) ) )
		return -EFAULT;

	DRM_DEBUG( "%d\n", ctx.handle );
	DRM(context_switch_complete)( dev, ctx.handle );

	return 0;
}

int DRM(rmctx)( struct inode *inode, struct file *filp,
		unsigned int cmd, unsigned long arg )
{
	drm_file_t *priv = filp->private_data;
	drm_device_t *dev = priv->dev;
	drm_ctx_t ctx;

	if ( copy_from_user( &ctx, (drm_ctx_t *)arg, sizeof(ctx) ) )
		return -EFAULT;

	DRM_DEBUG( "%d\n", ctx.handle );
	if ( ctx.handle == DRM_KERNEL_CONTEXT + 1 ) {
		priv->remove_auth_on_close = 1;
	}
	if ( ctx.handle != DRM_KERNEL_CONTEXT ) {
		DRM(ctxbitmap_free)( dev, ctx.handle );
	}

	return 0;
}