1 /* 2 * SPDX-License-Identifier: MIT 3 * 4 * Copyright © 2014-2016 Intel Corporation 5 */ 6 7 #include <linux/highmem.h> 8 #include <linux/shmem_fs.h> 9 #include <linux/swap.h> 10 11 #include <drm/drm.h> /* for drm_legacy.h! */ 12 #include <drm/drm_cache.h> 13 14 #include "gt/intel_gt.h" 15 #include "i915_drv.h" 16 #include "i915_gem_object.h" 17 #include "i915_gem_region.h" 18 #include "i915_scatterlist.h" 19 20 static int i915_gem_object_get_pages_phys(struct drm_i915_gem_object *obj) 21 { 22 struct address_space *mapping = obj->base.filp->f_mapping; 23 struct scatterlist *sg; 24 struct sg_table *st; 25 dma_addr_t dma; 26 void *vaddr; 27 void *dst; 28 int i; 29 30 if (GEM_WARN_ON(i915_gem_object_needs_bit17_swizzle(obj))) 31 return -EINVAL; 32 33 /* 34 * Always aligning to the object size, allows a single allocation 35 * to handle all possible callers, and given typical object sizes, 36 * the alignment of the buddy allocation will naturally match. 37 */ 38 vaddr = dma_alloc_coherent(&obj->base.dev->pdev->dev, 39 roundup_pow_of_two(obj->base.size), 40 &dma, GFP_KERNEL); 41 if (!vaddr) 42 return -ENOMEM; 43 44 st = kmalloc(sizeof(*st), GFP_KERNEL); 45 if (!st) 46 goto err_pci; 47 48 if (sg_alloc_table(st, 1, GFP_KERNEL)) 49 goto err_st; 50 51 sg = st->sgl; 52 sg->offset = 0; 53 sg->length = obj->base.size; 54 55 sg_assign_page(sg, (struct page *)vaddr); 56 sg_dma_address(sg) = dma; 57 sg_dma_len(sg) = obj->base.size; 58 59 dst = vaddr; 60 for (i = 0; i < obj->base.size / PAGE_SIZE; i++) { 61 struct page *page; 62 void *src; 63 64 page = shmem_read_mapping_page(mapping, i); 65 if (IS_ERR(page)) 66 goto err_st; 67 68 src = kmap_atomic(page); 69 memcpy(dst, src, PAGE_SIZE); 70 drm_clflush_virt_range(dst, PAGE_SIZE); 71 kunmap_atomic(src); 72 73 put_page(page); 74 dst += PAGE_SIZE; 75 } 76 77 intel_gt_chipset_flush(&to_i915(obj->base.dev)->gt); 78 79 __i915_gem_object_set_pages(obj, st, sg->length); 80 81 return 0; 82 83 err_st: 84 kfree(st); 85 err_pci: 86 dma_free_coherent(&obj->base.dev->pdev->dev, 87 roundup_pow_of_two(obj->base.size), 88 vaddr, dma); 89 return -ENOMEM; 90 } 91 92 static void 93 i915_gem_object_put_pages_phys(struct drm_i915_gem_object *obj, 94 struct sg_table *pages) 95 { 96 dma_addr_t dma = sg_dma_address(pages->sgl); 97 void *vaddr = sg_page(pages->sgl); 98 99 __i915_gem_object_release_shmem(obj, pages, false); 100 101 if (obj->mm.dirty) { 102 struct address_space *mapping = obj->base.filp->f_mapping; 103 void *src = vaddr; 104 int i; 105 106 for (i = 0; i < obj->base.size / PAGE_SIZE; i++) { 107 struct page *page; 108 char *dst; 109 110 page = shmem_read_mapping_page(mapping, i); 111 if (IS_ERR(page)) 112 continue; 113 114 dst = kmap_atomic(page); 115 drm_clflush_virt_range(src, PAGE_SIZE); 116 memcpy(dst, src, PAGE_SIZE); 117 kunmap_atomic(dst); 118 119 set_page_dirty(page); 120 if (obj->mm.madv == I915_MADV_WILLNEED) 121 mark_page_accessed(page); 122 put_page(page); 123 124 src += PAGE_SIZE; 125 } 126 obj->mm.dirty = false; 127 } 128 129 sg_free_table(pages); 130 kfree(pages); 131 132 dma_free_coherent(&obj->base.dev->pdev->dev, 133 roundup_pow_of_two(obj->base.size), 134 vaddr, dma); 135 } 136 137 static int 138 phys_pwrite(struct drm_i915_gem_object *obj, 139 const struct drm_i915_gem_pwrite *args) 140 { 141 void *vaddr = sg_page(obj->mm.pages->sgl) + args->offset; 142 char __user *user_data = u64_to_user_ptr(args->data_ptr); 143 int err; 144 145 err = i915_gem_object_wait(obj, 146 I915_WAIT_INTERRUPTIBLE | 147 I915_WAIT_ALL, 148 MAX_SCHEDULE_TIMEOUT); 149 if (err) 150 return err; 151 152 /* 153 * We manually control the domain here and pretend that it 154 * remains coherent i.e. in the GTT domain, like shmem_pwrite. 155 */ 156 i915_gem_object_invalidate_frontbuffer(obj, ORIGIN_CPU); 157 158 if (copy_from_user(vaddr, user_data, args->size)) 159 return -EFAULT; 160 161 drm_clflush_virt_range(vaddr, args->size); 162 intel_gt_chipset_flush(&to_i915(obj->base.dev)->gt); 163 164 i915_gem_object_flush_frontbuffer(obj, ORIGIN_CPU); 165 return 0; 166 } 167 168 static int 169 phys_pread(struct drm_i915_gem_object *obj, 170 const struct drm_i915_gem_pread *args) 171 { 172 void *vaddr = sg_page(obj->mm.pages->sgl) + args->offset; 173 char __user *user_data = u64_to_user_ptr(args->data_ptr); 174 int err; 175 176 err = i915_gem_object_wait(obj, 177 I915_WAIT_INTERRUPTIBLE, 178 MAX_SCHEDULE_TIMEOUT); 179 if (err) 180 return err; 181 182 drm_clflush_virt_range(vaddr, args->size); 183 if (copy_to_user(user_data, vaddr, args->size)) 184 return -EFAULT; 185 186 return 0; 187 } 188 189 static void phys_release(struct drm_i915_gem_object *obj) 190 { 191 fput(obj->base.filp); 192 } 193 194 static const struct drm_i915_gem_object_ops i915_gem_phys_ops = { 195 .name = "i915_gem_object_phys", 196 .get_pages = i915_gem_object_get_pages_phys, 197 .put_pages = i915_gem_object_put_pages_phys, 198 199 .pread = phys_pread, 200 .pwrite = phys_pwrite, 201 202 .release = phys_release, 203 }; 204 205 int i915_gem_object_attach_phys(struct drm_i915_gem_object *obj, int align) 206 { 207 struct sg_table *pages; 208 int err; 209 210 if (align > obj->base.size) 211 return -EINVAL; 212 213 if (obj->ops == &i915_gem_phys_ops) 214 return 0; 215 216 if (obj->ops != &i915_gem_shmem_ops) 217 return -EINVAL; 218 219 err = i915_gem_object_unbind(obj, I915_GEM_OBJECT_UNBIND_ACTIVE); 220 if (err) 221 return err; 222 223 mutex_lock_nested(&obj->mm.lock, I915_MM_GET_PAGES); 224 225 if (obj->mm.madv != I915_MADV_WILLNEED) { 226 err = -EFAULT; 227 goto err_unlock; 228 } 229 230 if (obj->mm.quirked) { 231 err = -EFAULT; 232 goto err_unlock; 233 } 234 235 if (obj->mm.mapping) { 236 err = -EBUSY; 237 goto err_unlock; 238 } 239 240 pages = __i915_gem_object_unset_pages(obj); 241 242 obj->ops = &i915_gem_phys_ops; 243 244 err = ____i915_gem_object_get_pages(obj); 245 if (err) 246 goto err_xfer; 247 248 /* Perma-pin (until release) the physical set of pages */ 249 __i915_gem_object_pin_pages(obj); 250 251 if (!IS_ERR_OR_NULL(pages)) 252 i915_gem_shmem_ops.put_pages(obj, pages); 253 254 i915_gem_object_release_memory_region(obj); 255 256 mutex_unlock(&obj->mm.lock); 257 return 0; 258 259 err_xfer: 260 obj->ops = &i915_gem_shmem_ops; 261 if (!IS_ERR_OR_NULL(pages)) { 262 unsigned int sg_page_sizes = i915_sg_page_sizes(pages->sgl); 263 264 __i915_gem_object_set_pages(obj, pages, sg_page_sizes); 265 } 266 err_unlock: 267 mutex_unlock(&obj->mm.lock); 268 return err; 269 } 270 271 #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST) 272 #include "selftests/i915_gem_phys.c" 273 #endif 274