1 /* $OpenBSD: drm_context.c,v 1.15 2011/06/02 18:22:00 weerd Exp $ */ 2 /*- 3 * Copyright 1999, 2000 Precision Insight, Inc., Cedar Park, Texas. 4 * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California. 5 * All Rights Reserved. 6 * 7 * Permission is hereby granted, free of charge, to any person obtaining a 8 * copy of this software and associated documentation files (the "Software"), 9 * to deal in the Software without restriction, including without limitation 10 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 11 * and/or sell copies of the Software, and to permit persons to whom the 12 * Software is furnished to do so, subject to the following conditions: 13 * 14 * The above copyright notice and this permission notice (including the next 15 * paragraph) shall be included in all copies or substantial portions of the 16 * Software. 17 * 18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 20 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 21 * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR 22 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 23 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR 24 * OTHER DEALINGS IN THE SOFTWARE. 25 * 26 * Authors: 27 * Rickard E. (Rik) Faith <faith@valinux.com> 28 * Gareth Hughes <gareth@valinux.com> 29 * 30 */ 31 32 /** @file drm_context.c 33 * Implementation of the context management ioctls. 34 */ 35 36 #include "drmP.h" 37 38 /* ================================================================ 39 * Context bitmap support 40 */ 41 42 void 43 drm_ctxbitmap_free(struct drm_device *dev, int ctx_handle) 44 { 45 if (ctx_handle < 0 || ctx_handle >= DRM_MAX_CTXBITMAP || 46 dev->ctx_bitmap == NULL) { 47 DRM_ERROR("Attempt to free invalid context handle: %d\n", 48 ctx_handle); 49 return; 50 } 51 52 DRM_LOCK(); 53 clear_bit(ctx_handle, dev->ctx_bitmap); 54 DRM_UNLOCK(); 55 return; 56 } 57 58 int 59 drm_ctxbitmap_next(struct drm_device *dev) 60 { 61 int bit; 62 63 if (dev->ctx_bitmap == NULL) 64 return (-1); 65 66 DRM_LOCK(); 67 bit = find_first_zero_bit(dev->ctx_bitmap, DRM_MAX_CTXBITMAP); 68 if (bit >= DRM_MAX_CTXBITMAP) { 69 DRM_UNLOCK(); 70 return (-1); 71 } 72 73 set_bit(bit, dev->ctx_bitmap); 74 DRM_DEBUG("drm_ctxbitmap_next bit : %d\n", bit); 75 DRM_UNLOCK(); 76 return (bit); 77 } 78 79 int 80 drm_ctxbitmap_init(struct drm_device *dev) 81 { 82 atomic_t *bitmap; 83 int i, temp; 84 85 86 if ((bitmap = drm_calloc(1, PAGE_SIZE)) == 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); 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 return (0); 151 } 152 153 int 154 drm_getctx(struct drm_device *dev, void *data, struct drm_file *file_priv) 155 { 156 struct drm_ctx *ctx = data; 157 158 /* This is 0, because we don't handle any context flags */ 159 ctx->flags = 0; 160 161 return (0); 162 } 163 164 int 165 drm_rmctx(struct drm_device *dev, void *data, struct drm_file *file_priv) 166 { 167 struct drm_ctx *ctx = data; 168 169 DRM_DEBUG("%d\n", ctx->handle); 170 if (ctx->handle != DRM_KERNEL_CONTEXT) 171 drm_ctxbitmap_free(dev, ctx->handle); 172 173 return (0); 174 } 175