1 // SPDX-License-Identifier: GPL-2.0+ 2 /* Copyright (C) 2015-2018 Broadcom */ 3 4 /** 5 * DOC: V3D GEM BO management support 6 * 7 * Compared to VC4 (V3D 2.x), V3D 3.3 introduces an MMU between the 8 * GPU and the bus, allowing us to use shmem objects for our storage 9 * instead of CMA. 10 * 11 * Physically contiguous objects may still be imported to V3D, but the 12 * driver doesn't allocate physically contiguous objects on its own. 13 * Display engines requiring physically contiguous allocations should 14 * look into Mesa's "renderonly" support (as used by the Mesa pl111 15 * driver) for an example of how to integrate with V3D. 16 * 17 * Long term, we should support evicting pages from the MMU when under 18 * memory pressure (thus the v3d_bo_get_pages() refcounting), but 19 * that's not a high priority since our systems tend to not have swap. 20 */ 21 22 #include <linux/dma-buf.h> 23 #include <linux/pfn_t.h> 24 25 #include "v3d_drv.h" 26 #include "uapi/drm/v3d_drm.h" 27 28 /* Called DRM core on the last userspace/kernel unreference of the 29 * BO. 30 */ 31 void v3d_free_object(struct drm_gem_object *obj) 32 { 33 struct v3d_dev *v3d = to_v3d_dev(obj->dev); 34 struct v3d_bo *bo = to_v3d_bo(obj); 35 36 v3d_mmu_remove_ptes(bo); 37 38 mutex_lock(&v3d->bo_lock); 39 v3d->bo_stats.num_allocated--; 40 v3d->bo_stats.pages_allocated -= obj->size >> PAGE_SHIFT; 41 mutex_unlock(&v3d->bo_lock); 42 43 spin_lock(&v3d->mm_lock); 44 drm_mm_remove_node(&bo->node); 45 spin_unlock(&v3d->mm_lock); 46 47 /* GPU execution may have dirtied any pages in the BO. */ 48 bo->base.pages_mark_dirty_on_put = true; 49 50 drm_gem_shmem_free_object(obj); 51 } 52 53 static const struct drm_gem_object_funcs v3d_gem_funcs = { 54 .free = v3d_free_object, 55 .print_info = drm_gem_shmem_print_info, 56 .pin = drm_gem_shmem_pin, 57 .unpin = drm_gem_shmem_unpin, 58 .get_sg_table = drm_gem_shmem_get_sg_table, 59 .vmap = drm_gem_shmem_vmap, 60 .vunmap = drm_gem_shmem_vunmap, 61 .vm_ops = &drm_gem_shmem_vm_ops, 62 }; 63 64 /* gem_create_object function for allocating a BO struct and doing 65 * early setup. 66 */ 67 struct drm_gem_object *v3d_create_object(struct drm_device *dev, size_t size) 68 { 69 struct v3d_bo *bo; 70 struct drm_gem_object *obj; 71 72 if (size == 0) 73 return NULL; 74 75 bo = kzalloc(sizeof(*bo), GFP_KERNEL); 76 if (!bo) 77 return NULL; 78 obj = &bo->base.base; 79 80 obj->funcs = &v3d_gem_funcs; 81 82 INIT_LIST_HEAD(&bo->unref_head); 83 84 return &bo->base.base; 85 } 86 87 static int 88 v3d_bo_create_finish(struct drm_gem_object *obj) 89 { 90 struct v3d_dev *v3d = to_v3d_dev(obj->dev); 91 struct v3d_bo *bo = to_v3d_bo(obj); 92 struct sg_table *sgt; 93 int ret; 94 95 /* So far we pin the BO in the MMU for its lifetime, so use 96 * shmem's helper for getting a lifetime sgt. 97 */ 98 sgt = drm_gem_shmem_get_pages_sgt(&bo->base.base); 99 if (IS_ERR(sgt)) 100 return PTR_ERR(sgt); 101 102 spin_lock(&v3d->mm_lock); 103 /* Allocate the object's space in the GPU's page tables. 104 * Inserting PTEs will happen later, but the offset is for the 105 * lifetime of the BO. 106 */ 107 ret = drm_mm_insert_node_generic(&v3d->mm, &bo->node, 108 obj->size >> PAGE_SHIFT, 109 GMP_GRANULARITY >> PAGE_SHIFT, 0, 0); 110 spin_unlock(&v3d->mm_lock); 111 if (ret) 112 return ret; 113 114 /* Track stats for /debug/dri/n/bo_stats. */ 115 mutex_lock(&v3d->bo_lock); 116 v3d->bo_stats.num_allocated++; 117 v3d->bo_stats.pages_allocated += obj->size >> PAGE_SHIFT; 118 mutex_unlock(&v3d->bo_lock); 119 120 v3d_mmu_insert_ptes(bo); 121 122 return 0; 123 } 124 125 struct v3d_bo *v3d_bo_create(struct drm_device *dev, struct drm_file *file_priv, 126 size_t unaligned_size) 127 { 128 struct drm_gem_shmem_object *shmem_obj; 129 struct v3d_bo *bo; 130 int ret; 131 132 shmem_obj = drm_gem_shmem_create(dev, unaligned_size); 133 if (IS_ERR(shmem_obj)) 134 return ERR_CAST(shmem_obj); 135 bo = to_v3d_bo(&shmem_obj->base); 136 137 ret = v3d_bo_create_finish(&shmem_obj->base); 138 if (ret) 139 goto free_obj; 140 141 return bo; 142 143 free_obj: 144 drm_gem_shmem_free_object(&shmem_obj->base); 145 return ERR_PTR(ret); 146 } 147 148 struct drm_gem_object * 149 v3d_prime_import_sg_table(struct drm_device *dev, 150 struct dma_buf_attachment *attach, 151 struct sg_table *sgt) 152 { 153 struct drm_gem_object *obj; 154 int ret; 155 156 obj = drm_gem_shmem_prime_import_sg_table(dev, attach, sgt); 157 if (IS_ERR(obj)) 158 return obj; 159 160 ret = v3d_bo_create_finish(obj); 161 if (ret) { 162 drm_gem_shmem_free_object(obj); 163 return ERR_PTR(ret); 164 } 165 166 return obj; 167 } 168 169 int v3d_create_bo_ioctl(struct drm_device *dev, void *data, 170 struct drm_file *file_priv) 171 { 172 struct drm_v3d_create_bo *args = data; 173 struct v3d_bo *bo = NULL; 174 int ret; 175 176 if (args->flags != 0) { 177 DRM_INFO("unknown create_bo flags: %d\n", args->flags); 178 return -EINVAL; 179 } 180 181 bo = v3d_bo_create(dev, file_priv, PAGE_ALIGN(args->size)); 182 if (IS_ERR(bo)) 183 return PTR_ERR(bo); 184 185 args->offset = bo->node.start << PAGE_SHIFT; 186 187 ret = drm_gem_handle_create(file_priv, &bo->base.base, &args->handle); 188 drm_gem_object_put_unlocked(&bo->base.base); 189 190 return ret; 191 } 192 193 int v3d_mmap_bo_ioctl(struct drm_device *dev, void *data, 194 struct drm_file *file_priv) 195 { 196 struct drm_v3d_mmap_bo *args = data; 197 struct drm_gem_object *gem_obj; 198 199 if (args->flags != 0) { 200 DRM_INFO("unknown mmap_bo flags: %d\n", args->flags); 201 return -EINVAL; 202 } 203 204 gem_obj = drm_gem_object_lookup(file_priv, args->handle); 205 if (!gem_obj) { 206 DRM_DEBUG("Failed to look up GEM BO %d\n", args->handle); 207 return -ENOENT; 208 } 209 210 args->offset = drm_vma_node_offset_addr(&gem_obj->vma_node); 211 drm_gem_object_put_unlocked(gem_obj); 212 213 return 0; 214 } 215 216 int v3d_get_bo_offset_ioctl(struct drm_device *dev, void *data, 217 struct drm_file *file_priv) 218 { 219 struct drm_v3d_get_bo_offset *args = data; 220 struct drm_gem_object *gem_obj; 221 struct v3d_bo *bo; 222 223 gem_obj = drm_gem_object_lookup(file_priv, args->handle); 224 if (!gem_obj) { 225 DRM_DEBUG("Failed to look up GEM BO %d\n", args->handle); 226 return -ENOENT; 227 } 228 bo = to_v3d_bo(gem_obj); 229 230 args->offset = bo->node.start << PAGE_SHIFT; 231 232 drm_gem_object_put_unlocked(gem_obj); 233 return 0; 234 } 235