1 // SPDX-License-Identifier: GPL-2.0 2 /* Copyright 2019 Linaro, Ltd, Rob Herring <robh@kernel.org> */ 3 4 #include <linux/err.h> 5 #include <linux/slab.h> 6 #include <linux/dma-buf.h> 7 #include <linux/dma-mapping.h> 8 9 #include <drm/panfrost_drm.h> 10 #include "panfrost_device.h" 11 #include "panfrost_gem.h" 12 #include "panfrost_mmu.h" 13 14 /* Called DRM core on the last userspace/kernel unreference of the 15 * BO. 16 */ 17 static void panfrost_gem_free_object(struct drm_gem_object *obj) 18 { 19 struct panfrost_gem_object *bo = to_panfrost_bo(obj); 20 struct panfrost_device *pfdev = obj->dev->dev_private; 21 22 /* 23 * Make sure the BO is no longer inserted in the shrinker list before 24 * taking care of the destruction itself. If we don't do that we have a 25 * race condition between this function and what's done in 26 * panfrost_gem_shrinker_scan(). 27 */ 28 mutex_lock(&pfdev->shrinker_lock); 29 list_del_init(&bo->base.madv_list); 30 mutex_unlock(&pfdev->shrinker_lock); 31 32 /* 33 * If we still have mappings attached to the BO, there's a problem in 34 * our refcounting. 35 */ 36 WARN_ON_ONCE(!list_empty(&bo->mappings.list)); 37 38 if (bo->sgts) { 39 int i; 40 int n_sgt = bo->base.base.size / SZ_2M; 41 42 for (i = 0; i < n_sgt; i++) { 43 if (bo->sgts[i].sgl) { 44 dma_unmap_sgtable(pfdev->dev, &bo->sgts[i], 45 DMA_BIDIRECTIONAL, 0); 46 sg_free_table(&bo->sgts[i]); 47 } 48 } 49 kvfree(bo->sgts); 50 } 51 52 drm_gem_shmem_free(&bo->base); 53 } 54 55 struct panfrost_gem_mapping * 56 panfrost_gem_mapping_get(struct panfrost_gem_object *bo, 57 struct panfrost_file_priv *priv) 58 { 59 struct panfrost_gem_mapping *iter, *mapping = NULL; 60 61 mutex_lock(&bo->mappings.lock); 62 list_for_each_entry(iter, &bo->mappings.list, node) { 63 if (iter->mmu == priv->mmu) { 64 kref_get(&iter->refcount); 65 mapping = iter; 66 break; 67 } 68 } 69 mutex_unlock(&bo->mappings.lock); 70 71 return mapping; 72 } 73 74 static void 75 panfrost_gem_teardown_mapping(struct panfrost_gem_mapping *mapping) 76 { 77 if (mapping->active) 78 panfrost_mmu_unmap(mapping); 79 80 spin_lock(&mapping->mmu->mm_lock); 81 if (drm_mm_node_allocated(&mapping->mmnode)) 82 drm_mm_remove_node(&mapping->mmnode); 83 spin_unlock(&mapping->mmu->mm_lock); 84 } 85 86 static void panfrost_gem_mapping_release(struct kref *kref) 87 { 88 struct panfrost_gem_mapping *mapping; 89 90 mapping = container_of(kref, struct panfrost_gem_mapping, refcount); 91 92 panfrost_gem_teardown_mapping(mapping); 93 drm_gem_object_put(&mapping->obj->base.base); 94 panfrost_mmu_ctx_put(mapping->mmu); 95 kfree(mapping); 96 } 97 98 void panfrost_gem_mapping_put(struct panfrost_gem_mapping *mapping) 99 { 100 if (!mapping) 101 return; 102 103 kref_put(&mapping->refcount, panfrost_gem_mapping_release); 104 } 105 106 void panfrost_gem_teardown_mappings_locked(struct panfrost_gem_object *bo) 107 { 108 struct panfrost_gem_mapping *mapping; 109 110 list_for_each_entry(mapping, &bo->mappings.list, node) 111 panfrost_gem_teardown_mapping(mapping); 112 } 113 114 int panfrost_gem_open(struct drm_gem_object *obj, struct drm_file *file_priv) 115 { 116 int ret; 117 size_t size = obj->size; 118 u64 align; 119 struct panfrost_gem_object *bo = to_panfrost_bo(obj); 120 unsigned long color = bo->noexec ? PANFROST_BO_NOEXEC : 0; 121 struct panfrost_file_priv *priv = file_priv->driver_priv; 122 struct panfrost_gem_mapping *mapping; 123 124 mapping = kzalloc(sizeof(*mapping), GFP_KERNEL); 125 if (!mapping) 126 return -ENOMEM; 127 128 INIT_LIST_HEAD(&mapping->node); 129 kref_init(&mapping->refcount); 130 drm_gem_object_get(obj); 131 mapping->obj = bo; 132 133 /* 134 * Executable buffers cannot cross a 16MB boundary as the program 135 * counter is 24-bits. We assume executable buffers will be less than 136 * 16MB and aligning executable buffers to their size will avoid 137 * crossing a 16MB boundary. 138 */ 139 if (!bo->noexec) 140 align = size >> PAGE_SHIFT; 141 else 142 align = size >= SZ_2M ? SZ_2M >> PAGE_SHIFT : 0; 143 144 mapping->mmu = panfrost_mmu_ctx_get(priv->mmu); 145 spin_lock(&mapping->mmu->mm_lock); 146 ret = drm_mm_insert_node_generic(&mapping->mmu->mm, &mapping->mmnode, 147 size >> PAGE_SHIFT, align, color, 0); 148 spin_unlock(&mapping->mmu->mm_lock); 149 if (ret) 150 goto err; 151 152 if (!bo->is_heap) { 153 ret = panfrost_mmu_map(mapping); 154 if (ret) 155 goto err; 156 } 157 158 mutex_lock(&bo->mappings.lock); 159 WARN_ON(bo->base.madv != PANFROST_MADV_WILLNEED); 160 list_add_tail(&mapping->node, &bo->mappings.list); 161 mutex_unlock(&bo->mappings.lock); 162 163 err: 164 if (ret) 165 panfrost_gem_mapping_put(mapping); 166 return ret; 167 } 168 169 void panfrost_gem_close(struct drm_gem_object *obj, struct drm_file *file_priv) 170 { 171 struct panfrost_file_priv *priv = file_priv->driver_priv; 172 struct panfrost_gem_object *bo = to_panfrost_bo(obj); 173 struct panfrost_gem_mapping *mapping = NULL, *iter; 174 175 mutex_lock(&bo->mappings.lock); 176 list_for_each_entry(iter, &bo->mappings.list, node) { 177 if (iter->mmu == priv->mmu) { 178 mapping = iter; 179 list_del(&iter->node); 180 break; 181 } 182 } 183 mutex_unlock(&bo->mappings.lock); 184 185 panfrost_gem_mapping_put(mapping); 186 } 187 188 static int panfrost_gem_pin(struct drm_gem_object *obj) 189 { 190 struct panfrost_gem_object *bo = to_panfrost_bo(obj); 191 192 if (bo->is_heap) 193 return -EINVAL; 194 195 return drm_gem_shmem_pin(&bo->base); 196 } 197 198 static const struct drm_gem_object_funcs panfrost_gem_funcs = { 199 .free = panfrost_gem_free_object, 200 .open = panfrost_gem_open, 201 .close = panfrost_gem_close, 202 .print_info = drm_gem_shmem_object_print_info, 203 .pin = panfrost_gem_pin, 204 .unpin = drm_gem_shmem_object_unpin, 205 .get_sg_table = drm_gem_shmem_object_get_sg_table, 206 .vmap = drm_gem_shmem_object_vmap, 207 .vunmap = drm_gem_shmem_object_vunmap, 208 .mmap = drm_gem_shmem_object_mmap, 209 .vm_ops = &drm_gem_shmem_vm_ops, 210 }; 211 212 /** 213 * panfrost_gem_create_object - Implementation of driver->gem_create_object. 214 * @dev: DRM device 215 * @size: Size in bytes of the memory the object will reference 216 * 217 * This lets the GEM helpers allocate object structs for us, and keep 218 * our BO stats correct. 219 */ 220 struct drm_gem_object *panfrost_gem_create_object(struct drm_device *dev, size_t size) 221 { 222 struct panfrost_device *pfdev = dev->dev_private; 223 struct panfrost_gem_object *obj; 224 225 obj = kzalloc(sizeof(*obj), GFP_KERNEL); 226 if (!obj) 227 return ERR_PTR(-ENOMEM); 228 229 INIT_LIST_HEAD(&obj->mappings.list); 230 mutex_init(&obj->mappings.lock); 231 obj->base.base.funcs = &panfrost_gem_funcs; 232 obj->base.map_wc = !pfdev->coherent; 233 234 return &obj->base.base; 235 } 236 237 struct panfrost_gem_object * 238 panfrost_gem_create(struct drm_device *dev, size_t size, u32 flags) 239 { 240 struct drm_gem_shmem_object *shmem; 241 struct panfrost_gem_object *bo; 242 243 /* Round up heap allocations to 2MB to keep fault handling simple */ 244 if (flags & PANFROST_BO_HEAP) 245 size = roundup(size, SZ_2M); 246 247 shmem = drm_gem_shmem_create(dev, size); 248 if (IS_ERR(shmem)) 249 return ERR_CAST(shmem); 250 251 bo = to_panfrost_bo(&shmem->base); 252 bo->noexec = !!(flags & PANFROST_BO_NOEXEC); 253 bo->is_heap = !!(flags & PANFROST_BO_HEAP); 254 255 return bo; 256 } 257 258 struct drm_gem_object * 259 panfrost_gem_prime_import_sg_table(struct drm_device *dev, 260 struct dma_buf_attachment *attach, 261 struct sg_table *sgt) 262 { 263 struct drm_gem_object *obj; 264 struct panfrost_gem_object *bo; 265 266 obj = drm_gem_shmem_prime_import_sg_table(dev, attach, sgt); 267 if (IS_ERR(obj)) 268 return ERR_CAST(obj); 269 270 bo = to_panfrost_bo(obj); 271 bo->noexec = true; 272 273 return obj; 274 } 275