1 // SPDX-License-Identifier: MIT 2 /* 3 * Copyright © 2021 Intel Corporation 4 */ 5 #include <drm/ttm/ttm_bo_driver.h> 6 #include <drm/ttm/ttm_device.h> 7 #include <drm/ttm/ttm_range_manager.h> 8 9 #include "i915_drv.h" 10 #include "i915_scatterlist.h" 11 #include "i915_ttm_buddy_manager.h" 12 13 #include "intel_region_ttm.h" 14 15 #include "gem/i915_gem_ttm.h" /* For the funcs/ops export only */ 16 /** 17 * DOC: TTM support structure 18 * 19 * The code in this file deals with setting up memory managers for TTM 20 * LMEM and MOCK regions and converting the output from 21 * the managers to struct sg_table, Basically providing the mapping from 22 * i915 GEM regions to TTM memory types and resource managers. 23 */ 24 25 /** 26 * intel_region_ttm_device_init - Initialize a TTM device 27 * @dev_priv: Pointer to an i915 device private structure. 28 * 29 * Return: 0 on success, negative error code on failure. 30 */ 31 int intel_region_ttm_device_init(struct drm_i915_private *dev_priv) 32 { 33 struct drm_device *drm = &dev_priv->drm; 34 35 return ttm_device_init(&dev_priv->bdev, i915_ttm_driver(), 36 drm->dev, drm->anon_inode->i_mapping, 37 drm->vma_offset_manager, false, false); 38 } 39 40 /** 41 * intel_region_ttm_device_fini - Finalize a TTM device 42 * @dev_priv: Pointer to an i915 device private structure. 43 */ 44 void intel_region_ttm_device_fini(struct drm_i915_private *dev_priv) 45 { 46 ttm_device_fini(&dev_priv->bdev); 47 } 48 49 /* 50 * Map the i915 memory regions to TTM memory types. We use the 51 * driver-private types for now, reserving TTM_PL_VRAM for stolen 52 * memory and TTM_PL_TT for GGTT use if decided to implement this. 53 */ 54 int intel_region_to_ttm_type(const struct intel_memory_region *mem) 55 { 56 int type; 57 58 GEM_BUG_ON(mem->type != INTEL_MEMORY_LOCAL && 59 mem->type != INTEL_MEMORY_MOCK && 60 mem->type != INTEL_MEMORY_SYSTEM); 61 62 if (mem->type == INTEL_MEMORY_SYSTEM) 63 return TTM_PL_SYSTEM; 64 65 type = mem->instance + TTM_PL_PRIV; 66 GEM_BUG_ON(type >= TTM_NUM_MEM_TYPES); 67 68 return type; 69 } 70 71 /** 72 * intel_region_ttm_init - Initialize a memory region for TTM. 73 * @mem: The region to initialize. 74 * 75 * This function initializes a suitable TTM resource manager for the 76 * region, and if it's a LMEM region type, attaches it to the TTM 77 * device. MOCK regions are NOT attached to the TTM device, since we don't 78 * have one for the mock selftests. 79 * 80 * Return: 0 on success, negative error code on failure. 81 */ 82 int intel_region_ttm_init(struct intel_memory_region *mem) 83 { 84 struct ttm_device *bdev = &mem->i915->bdev; 85 int mem_type = intel_region_to_ttm_type(mem); 86 int ret; 87 88 ret = i915_ttm_buddy_man_init(bdev, mem_type, false, 89 resource_size(&mem->region), 90 mem->min_page_size, PAGE_SIZE); 91 if (ret) 92 return ret; 93 94 mem->region_private = ttm_manager_type(bdev, mem_type); 95 96 return 0; 97 } 98 99 /** 100 * intel_region_ttm_fini - Finalize a TTM region. 101 * @mem: The memory region 102 * 103 * This functions takes down the TTM resource manager associated with the 104 * memory region, and if it was registered with the TTM device, 105 * removes that registration. 106 */ 107 int intel_region_ttm_fini(struct intel_memory_region *mem) 108 { 109 struct ttm_resource_manager *man = mem->region_private; 110 int ret = -EBUSY; 111 int count; 112 113 /* 114 * Put the region's move fences. This releases requests that 115 * may hold on to contexts and vms that may hold on to buffer 116 * objects placed in this region. 117 */ 118 if (man) 119 ttm_resource_manager_cleanup(man); 120 121 /* Flush objects from region. */ 122 for (count = 0; count < 10; ++count) { 123 i915_gem_flush_free_objects(mem->i915); 124 125 mutex_lock(&mem->objects.lock); 126 if (list_empty(&mem->objects.list)) 127 ret = 0; 128 mutex_unlock(&mem->objects.lock); 129 if (!ret) 130 break; 131 132 msleep(20); 133 flush_delayed_work(&mem->i915->bdev.wq); 134 } 135 136 /* If we leaked objects, Don't free the region causing use after free */ 137 if (ret || !man) 138 return ret; 139 140 ret = i915_ttm_buddy_man_fini(&mem->i915->bdev, 141 intel_region_to_ttm_type(mem)); 142 GEM_WARN_ON(ret); 143 mem->region_private = NULL; 144 145 return ret; 146 } 147 148 /** 149 * intel_region_ttm_resource_to_rsgt - 150 * Convert an opaque TTM resource manager resource to a refcounted sg_table. 151 * @mem: The memory region. 152 * @res: The resource manager resource obtained from the TTM resource manager. 153 * 154 * The gem backends typically use sg-tables for operations on the underlying 155 * io_memory. So provide a way for the backends to translate the 156 * nodes they are handed from TTM to sg-tables. 157 * 158 * Return: A malloced sg_table on success, an error pointer on failure. 159 */ 160 struct i915_refct_sgt * 161 intel_region_ttm_resource_to_rsgt(struct intel_memory_region *mem, 162 struct ttm_resource *res) 163 { 164 if (mem->is_range_manager) { 165 struct ttm_range_mgr_node *range_node = 166 to_ttm_range_mgr_node(res); 167 168 return i915_rsgt_from_mm_node(&range_node->mm_nodes[0], 169 mem->region.start); 170 } else { 171 return i915_rsgt_from_buddy_resource(res, mem->region.start); 172 } 173 } 174 175 #ifdef CONFIG_DRM_I915_SELFTEST 176 /** 177 * intel_region_ttm_resource_alloc - Allocate memory resources from a region 178 * @mem: The memory region, 179 * @size: The requested size in bytes 180 * @flags: Allocation flags 181 * 182 * This functionality is provided only for callers that need to allocate 183 * memory from standalone TTM range managers, without the TTM eviction 184 * functionality. Don't use if you are not completely sure that's the 185 * case. The returned opaque node can be converted to an sg_table using 186 * intel_region_ttm_resource_to_st(), and can be freed using 187 * intel_region_ttm_resource_free(). 188 * 189 * Return: A valid pointer on success, an error pointer on failure. 190 */ 191 struct ttm_resource * 192 intel_region_ttm_resource_alloc(struct intel_memory_region *mem, 193 resource_size_t size, 194 unsigned int flags) 195 { 196 struct ttm_resource_manager *man = mem->region_private; 197 struct ttm_place place = {}; 198 struct ttm_buffer_object mock_bo = {}; 199 struct ttm_resource *res; 200 int ret; 201 202 mock_bo.base.size = size; 203 mock_bo.bdev = &mem->i915->bdev; 204 place.flags = flags; 205 206 ret = man->func->alloc(man, &mock_bo, &place, &res); 207 if (ret == -ENOSPC) 208 ret = -ENXIO; 209 if (!ret) 210 res->bo = NULL; /* Rather blow up, then some uaf */ 211 return ret ? ERR_PTR(ret) : res; 212 } 213 214 #endif 215 216 /** 217 * intel_region_ttm_resource_free - Free a resource allocated from a resource manager 218 * @mem: The region the resource was allocated from. 219 * @res: The opaque resource representing an allocation. 220 */ 221 void intel_region_ttm_resource_free(struct intel_memory_region *mem, 222 struct ttm_resource *res) 223 { 224 struct ttm_resource_manager *man = mem->region_private; 225 struct ttm_buffer_object mock_bo = {}; 226 227 mock_bo.base.size = res->num_pages << PAGE_SHIFT; 228 mock_bo.bdev = &mem->i915->bdev; 229 res->bo = &mock_bo; 230 231 man->func->free(man, res); 232 } 233