xref: /openbsd-src/sys/dev/pci/drm/drm_context.c (revision 850e275390052b330d93020bf619a739a3c277ac)
1 /*-
2  * Copyright 1999, 2000 Precision Insight, Inc., Cedar Park, Texas.
3  * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
4  * All Rights Reserved.
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a
7  * copy of this software and associated documentation files (the "Software"),
8  * to deal in the Software without restriction, including without limitation
9  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10  * and/or sell copies of the Software, and to permit persons to whom the
11  * Software is furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice (including the next
14  * paragraph) shall be included in all copies or substantial portions of the
15  * Software.
16  *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
20  * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
21  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
22  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
23  * OTHER DEALINGS IN THE SOFTWARE.
24  *
25  * Authors:
26  *    Rickard E. (Rik) Faith <faith@valinux.com>
27  *    Gareth Hughes <gareth@valinux.com>
28  *
29  */
30 
31 /** @file drm_context.c
32  * Implementation of the context management ioctls.
33  */
34 
35 #include "drmP.h"
36 
37 /* ================================================================
38  * Context bitmap support
39  */
40 
41 void
42 drm_ctxbitmap_free(struct drm_device *dev, int ctx_handle)
43 {
44 	if (ctx_handle < 0 || ctx_handle >= DRM_MAX_CTXBITMAP ||
45 	    dev->ctx_bitmap == NULL) {
46 		DRM_ERROR("Attempt to free invalid context handle: %d\n",
47 		   ctx_handle);
48 		return;
49 	}
50 
51 	DRM_LOCK();
52 	clear_bit(ctx_handle, dev->ctx_bitmap);
53 	DRM_UNLOCK();
54 	return;
55 }
56 
57 int
58 drm_ctxbitmap_next(struct drm_device *dev)
59 {
60 	int bit;
61 
62 	if (dev->ctx_bitmap == NULL)
63 		return -1;
64 
65 	DRM_LOCK();
66 	bit = find_first_zero_bit(dev->ctx_bitmap, DRM_MAX_CTXBITMAP);
67 	if (bit >= DRM_MAX_CTXBITMAP) {
68 		DRM_UNLOCK();
69 		return -1;
70 	}
71 
72 	set_bit(bit, dev->ctx_bitmap);
73 	DRM_DEBUG("drm_ctxbitmap_next bit : %d\n", bit);
74 	DRM_UNLOCK();
75 	return bit;
76 }
77 
78 int
79 drm_ctxbitmap_init(struct drm_device *dev)
80 {
81 	atomic_t	*bitmap;
82 	int		 i, temp;
83 
84 
85 	bitmap = drm_calloc(1, PAGE_SIZE, DRM_MEM_CTXBITMAP);
86 	if (bitmap == NULL)
87 		return (ENOMEM);
88 	DRM_LOCK();
89 	dev->ctx_bitmap = bitmap;
90 	DRM_UNLOCK();
91 
92 	for (i = 0; i < DRM_RESERVED_CONTEXTS; i++) {
93 		temp = drm_ctxbitmap_next(dev);
94 	   	DRM_DEBUG("drm_ctxbitmap_init : %d\n", temp);
95 	}
96 
97 	return 0;
98 }
99 
100 void
101 drm_ctxbitmap_cleanup(struct drm_device *dev)
102 {
103 	atomic_t *bitmap;
104 
105 	DRM_LOCK();
106 	bitmap = dev->ctx_bitmap;
107 	dev->ctx_bitmap = NULL;
108 	DRM_UNLOCK();
109 	drm_free(bitmap, PAGE_SIZE, DRM_MEM_CTXBITMAP);
110 }
111 
112 int
113 drm_resctx(struct drm_device *dev, void *data, struct drm_file *file_priv)
114 {
115 	struct drm_ctx_res	*res = data;
116 	struct drm_ctx		 ctx;
117 	int			 i;
118 
119 	if (res->count >= DRM_RESERVED_CONTEXTS) {
120 		bzero(&ctx, sizeof(ctx));
121 		for (i = 0; i < DRM_RESERVED_CONTEXTS; i++) {
122 			ctx.handle = i;
123 			if (DRM_COPY_TO_USER(&res->contexts[i],
124 			    &ctx, sizeof(ctx)))
125 				return EFAULT;
126 		}
127 	}
128 	res->count = DRM_RESERVED_CONTEXTS;
129 
130 	return 0;
131 }
132 
133 int
134 drm_addctx(struct drm_device *dev, void *data, struct drm_file *file_priv)
135 {
136 	struct drm_ctx	*ctx = data;
137 
138 	ctx->handle = drm_ctxbitmap_next(dev);
139 	if (ctx->handle == DRM_KERNEL_CONTEXT) {
140 		/* Skip kernel's context and get a new one. */
141 		ctx->handle = drm_ctxbitmap_next(dev);
142 	}
143 	DRM_DEBUG("%d\n", ctx->handle);
144 	if (ctx->handle == -1) {
145 		DRM_DEBUG("Not enough free contexts.\n");
146 		/* Should this return -EBUSY instead? */
147 		return ENOMEM;
148 	}
149 
150 	if (dev->driver.context_ctor && ctx->handle != DRM_KERNEL_CONTEXT)
151 		dev->driver.context_ctor(dev, ctx->handle);
152 
153 	return 0;
154 }
155 
156 int
157 drm_getctx(struct drm_device *dev, void *data, struct drm_file *file_priv)
158 {
159 	struct drm_ctx	*ctx = data;
160 
161 	/* This is 0, because we don't handle any context flags */
162 	ctx->flags = 0;
163 
164 	return 0;
165 }
166 
167 int
168 drm_rmctx(struct drm_device *dev, void *data, struct drm_file *file_priv)
169 {
170 	struct drm_ctx	*ctx = data;
171 
172 	DRM_DEBUG("%d\n", ctx->handle);
173 	if (ctx->handle != DRM_KERNEL_CONTEXT) {
174 		if (dev->driver.context_dtor)
175 			dev->driver.context_dtor(dev, ctx->handle);
176 
177 		drm_ctxbitmap_free(dev, ctx->handle);
178 	}
179 
180 	return 0;
181 }
182