1 /* context.c -- IOCTLs for contexts and DMA queues -*- linux-c -*-
2  * Created: Tue Feb  2 08:37:54 1999 by faith@precisioninsight.com
3  *
4  * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
5  * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
6  * All Rights Reserved.
7  *
8  * Permission is hereby granted, free of charge, to any person obtaining a
9  * copy of this software and associated documentation files (the "Software"),
10  * to deal in the Software without restriction, including without limitation
11  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
12  * and/or sell copies of the Software, and to permit persons to whom the
13  * Software is furnished to do so, subject to the following conditions:
14  *
15  * The above copyright notice and this permission notice (including the next
16  * paragraph) shall be included in all copies or substantial portions of the
17  * Software.
18  *
19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
20  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
21  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
22  * PRECISION INSIGHT AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
23  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
24  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
25  * DEALINGS IN THE SOFTWARE.
26  *
27  * Authors:
28  *    Rickard E. (Rik) Faith <faith@valinux.com>
29  *
30  */
31 
32 #define __NO_VERSION__
33 #include "drmP.h"
34 
drm_init_queue(drm_device_t * dev,drm_queue_t * q,drm_ctx_t * ctx)35 static int drm_init_queue(drm_device_t *dev, drm_queue_t *q, drm_ctx_t *ctx)
36 {
37 	DRM_DEBUG("\n");
38 
39 	if (atomic_read(&q->use_count) != 1
40 	    || atomic_read(&q->finalization)
41 	    || atomic_read(&q->block_count)) {
42 		DRM_ERROR("New queue is already in use: u%d f%d b%d\n",
43 			  atomic_read(&q->use_count),
44 			  atomic_read(&q->finalization),
45 			  atomic_read(&q->block_count));
46 	}
47 
48 	atomic_set(&q->finalization,  0);
49 	atomic_set(&q->block_count,   0);
50 	atomic_set(&q->block_read,    0);
51 	atomic_set(&q->block_write,   0);
52 	atomic_set(&q->total_queued,  0);
53 	atomic_set(&q->total_flushed, 0);
54 	atomic_set(&q->total_locks,   0);
55 
56 	init_waitqueue_head(&q->write_queue);
57 	init_waitqueue_head(&q->read_queue);
58 	init_waitqueue_head(&q->flush_queue);
59 
60 	q->flags = ctx->flags;
61 
62 	drm_waitlist_create(&q->waitlist, dev->dma->buf_count);
63 
64 	return 0;
65 }
66 
67 
68 /* drm_alloc_queue:
69 PRE: 1) dev->queuelist[0..dev->queue_count] is allocated and will not
70 	disappear (so all deallocation must be done after IOCTLs are off)
71      2) dev->queue_count < dev->queue_slots
72      3) dev->queuelist[i].use_count == 0 and
73 	dev->queuelist[i].finalization == 0 if i not in use
74 POST: 1) dev->queuelist[i].use_count == 1
75       2) dev->queue_count < dev->queue_slots */
76 
drm_alloc_queue(drm_device_t * dev)77 static int drm_alloc_queue(drm_device_t *dev)
78 {
79 	int	    i;
80 	drm_queue_t *queue;
81 	int	    oldslots;
82 	int	    newslots;
83 				/* Check for a free queue */
84 	for (i = 0; i < dev->queue_count; i++) {
85 		atomic_inc(&dev->queuelist[i]->use_count);
86 		if (atomic_read(&dev->queuelist[i]->use_count) == 1
87 		    && !atomic_read(&dev->queuelist[i]->finalization)) {
88 			DRM_DEBUG("%d (free)\n", i);
89 			return i;
90 		}
91 		atomic_dec(&dev->queuelist[i]->use_count);
92 	}
93 				/* Allocate a new queue */
94 
95 	queue = drm_alloc(sizeof(*queue), DRM_MEM_QUEUES);
96 	if(queue == NULL)
97 		return -ENOMEM;
98 
99 	memset(queue, 0, sizeof(*queue));
100 	down(&dev->struct_sem);
101 	atomic_set(&queue->use_count, 1);
102 
103 	++dev->queue_count;
104 	if (dev->queue_count >= dev->queue_slots) {
105 		oldslots = dev->queue_slots * sizeof(*dev->queuelist);
106 		if (!dev->queue_slots) dev->queue_slots = 1;
107 		dev->queue_slots *= 2;
108 		newslots = dev->queue_slots * sizeof(*dev->queuelist);
109 
110 		dev->queuelist = drm_realloc(dev->queuelist,
111 					     oldslots,
112 					     newslots,
113 					     DRM_MEM_QUEUES);
114 		if (!dev->queuelist) {
115 			up(&dev->struct_sem);
116 			DRM_DEBUG("out of memory\n");
117 			return -ENOMEM;
118 		}
119 	}
120 	dev->queuelist[dev->queue_count-1] = queue;
121 
122 	up(&dev->struct_sem);
123 	DRM_DEBUG("%d (new)\n", dev->queue_count - 1);
124 	return dev->queue_count - 1;
125 }
126 
drm_resctx(struct inode * inode,struct file * filp,unsigned int cmd,unsigned long arg)127 int drm_resctx(struct inode *inode, struct file *filp, unsigned int cmd,
128 	       unsigned long arg)
129 {
130 	drm_ctx_res_t	res;
131 	drm_ctx_t	ctx;
132 	int		i;
133 
134 	DRM_DEBUG("%d\n", DRM_RESERVED_CONTEXTS);
135 	if (copy_from_user(&res, (drm_ctx_res_t *)arg, sizeof(res)))
136 		return -EFAULT;
137 	if (res.count >= DRM_RESERVED_CONTEXTS) {
138 		memset(&ctx, 0, sizeof(ctx));
139 		for (i = 0; i < DRM_RESERVED_CONTEXTS; i++) {
140 			ctx.handle = i;
141 			if (copy_to_user(&res.contexts[i],
142 					 &i,
143 					 sizeof(i)))
144 				return -EFAULT;
145 		}
146 	}
147 	res.count = DRM_RESERVED_CONTEXTS;
148 	if (copy_to_user((drm_ctx_res_t *)arg, &res, sizeof(res)))
149 		return -EFAULT;
150 	return 0;
151 }
152 
153 
drm_addctx(struct inode * inode,struct file * filp,unsigned int cmd,unsigned long arg)154 int drm_addctx(struct inode *inode, struct file *filp, unsigned int cmd,
155 	       unsigned long arg)
156 {
157 	drm_file_t	*priv	= filp->private_data;
158 	drm_device_t	*dev	= priv->dev;
159 	drm_ctx_t	ctx;
160 
161 	if (copy_from_user(&ctx, (drm_ctx_t *)arg, sizeof(ctx)))
162 		return -EFAULT;
163 	if ((ctx.handle = drm_alloc_queue(dev)) == DRM_KERNEL_CONTEXT) {
164 				/* Init kernel's context and get a new one. */
165 		drm_init_queue(dev, dev->queuelist[ctx.handle], &ctx);
166 		ctx.handle = drm_alloc_queue(dev);
167 	}
168 	drm_init_queue(dev, dev->queuelist[ctx.handle], &ctx);
169 	DRM_DEBUG("%d\n", ctx.handle);
170 	if (copy_to_user((drm_ctx_t *)arg, &ctx, sizeof(ctx)))
171 		return -EFAULT;
172 	return 0;
173 }
174 
drm_modctx(struct inode * inode,struct file * filp,unsigned int cmd,unsigned long arg)175 int drm_modctx(struct inode *inode, struct file *filp, unsigned int cmd,
176 	       unsigned long arg)
177 {
178 	drm_file_t	*priv	= filp->private_data;
179 	drm_device_t	*dev	= priv->dev;
180 	drm_ctx_t	ctx;
181 	drm_queue_t	*q;
182 
183 	if (copy_from_user(&ctx, (drm_ctx_t *)arg, sizeof(ctx)))
184 		return -EFAULT;
185 
186 	DRM_DEBUG("%d\n", ctx.handle);
187 
188 	if (ctx.handle < 0 || ctx.handle >= dev->queue_count) return -EINVAL;
189 	q = dev->queuelist[ctx.handle];
190 
191 	atomic_inc(&q->use_count);
192 	if (atomic_read(&q->use_count) == 1) {
193 				/* No longer in use */
194 		atomic_dec(&q->use_count);
195 		return -EINVAL;
196 	}
197 
198 	if (DRM_BUFCOUNT(&q->waitlist)) {
199 		atomic_dec(&q->use_count);
200 		return -EBUSY;
201 	}
202 
203 	q->flags = ctx.flags;
204 
205 	atomic_dec(&q->use_count);
206 	return 0;
207 }
208 
drm_getctx(struct inode * inode,struct file * filp,unsigned int cmd,unsigned long arg)209 int drm_getctx(struct inode *inode, struct file *filp, unsigned int cmd,
210 	       unsigned long arg)
211 {
212 	drm_file_t	*priv	= filp->private_data;
213 	drm_device_t	*dev	= priv->dev;
214 	drm_ctx_t	ctx;
215 	drm_queue_t	*q;
216 
217 	if (copy_from_user(&ctx, (drm_ctx_t *)arg, sizeof(ctx)))
218 		return -EFAULT;
219 
220 	DRM_DEBUG("%d\n", ctx.handle);
221 
222 	if (ctx.handle >= dev->queue_count) return -EINVAL;
223 	q = dev->queuelist[ctx.handle];
224 
225 	atomic_inc(&q->use_count);
226 	if (atomic_read(&q->use_count) == 1) {
227 				/* No longer in use */
228 		atomic_dec(&q->use_count);
229 		return -EINVAL;
230 	}
231 
232 	ctx.flags = q->flags;
233 	atomic_dec(&q->use_count);
234 
235 	if (copy_to_user((drm_ctx_t *)arg, &ctx, sizeof(ctx)))
236 		return -EFAULT;
237 
238 	return 0;
239 }
240 
drm_switchctx(struct inode * inode,struct file * filp,unsigned int cmd,unsigned long arg)241 int drm_switchctx(struct inode *inode, struct file *filp, unsigned int cmd,
242 		  unsigned long arg)
243 {
244 	drm_file_t	*priv	= filp->private_data;
245 	drm_device_t	*dev	= priv->dev;
246 	drm_ctx_t	ctx;
247 
248 	if (copy_from_user(&ctx, (drm_ctx_t *)arg, sizeof(ctx)))
249 		return -EFAULT;
250 	DRM_DEBUG("%d\n", ctx.handle);
251 	return drm_context_switch(dev, dev->last_context, ctx.handle);
252 }
253 
drm_newctx(struct inode * inode,struct file * filp,unsigned int cmd,unsigned long arg)254 int drm_newctx(struct inode *inode, struct file *filp, unsigned int cmd,
255 	       unsigned long arg)
256 {
257 	drm_file_t	*priv	= filp->private_data;
258 	drm_device_t	*dev	= priv->dev;
259 	drm_ctx_t	ctx;
260 
261 	if (copy_from_user(&ctx, (drm_ctx_t *)arg, sizeof(ctx)))
262 		return -EFAULT;
263 	DRM_DEBUG("%d\n", ctx.handle);
264 	drm_context_switch_complete(dev, ctx.handle);
265 
266 	return 0;
267 }
268 
drm_rmctx(struct inode * inode,struct file * filp,unsigned int cmd,unsigned long arg)269 int drm_rmctx(struct inode *inode, struct file *filp, unsigned int cmd,
270 	      unsigned long arg)
271 {
272 	drm_file_t	*priv	= filp->private_data;
273 	drm_device_t	*dev	= priv->dev;
274 	drm_ctx_t	ctx;
275 	drm_queue_t	*q;
276 	drm_buf_t	*buf;
277 
278 	if (copy_from_user(&ctx, (drm_ctx_t *)arg, sizeof(ctx)))
279 		return -EFAULT;
280 	DRM_DEBUG("%d\n", ctx.handle);
281 
282 	if (ctx.handle >= dev->queue_count) return -EINVAL;
283 	q = dev->queuelist[ctx.handle];
284 
285 	atomic_inc(&q->use_count);
286 	if (atomic_read(&q->use_count) == 1) {
287 				/* No longer in use */
288 		atomic_dec(&q->use_count);
289 		return -EINVAL;
290 	}
291 
292 	atomic_inc(&q->finalization); /* Mark queue in finalization state */
293 	atomic_sub(2, &q->use_count); /* Mark queue as unused (pending
294 					 finalization) */
295 
296 	while (test_and_set_bit(0, &dev->interrupt_flag)) {
297 		schedule();
298 		if (signal_pending(current)) {
299 			clear_bit(0, &dev->interrupt_flag);
300 			return -EINTR;
301 		}
302 	}
303 				/* Remove queued buffers */
304 	while ((buf = drm_waitlist_get(&q->waitlist))) {
305 		drm_free_buffer(dev, buf);
306 	}
307 	clear_bit(0, &dev->interrupt_flag);
308 
309 				/* Wakeup blocked processes */
310 	wake_up_interruptible(&q->read_queue);
311 	wake_up_interruptible(&q->write_queue);
312 	wake_up_interruptible(&q->flush_queue);
313 
314 				/* Finalization over.  Queue is made
315 				   available when both use_count and
316 				   finalization become 0, which won't
317 				   happen until all the waiting processes
318 				   stop waiting. */
319 	atomic_dec(&q->finalization);
320 	return 0;
321 }
322