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_cache.h> 12 13 #include "gt/intel_gt.h" 14 #include "i915_drv.h" 15 #include "i915_gem_object.h" 16 #include "i915_gem_object_frontbuffer.h" 17 #include "i915_gem_region.h" 18 #include "i915_gem_tiling.h" 19 #include "i915_scatterlist.h" 20 21 static int i915_gem_object_get_pages_phys(struct drm_i915_gem_object *obj) 22 { 23 struct address_space *mapping = obj->base.filp->f_mapping; 24 struct drm_i915_private *i915 = to_i915(obj->base.dev); 25 struct scatterlist *sg; 26 struct sg_table *st; 27 dma_addr_t dma; 28 void *vaddr; 29 void *dst; 30 int i; 31 32 /* Contiguous chunk, with a single scatterlist element */ 33 if (overflows_type(obj->base.size, sg->length)) 34 return -E2BIG; 35 36 if (GEM_WARN_ON(i915_gem_object_needs_bit17_swizzle(obj))) 37 return -EINVAL; 38 39 /* 40 * Always aligning to the object size, allows a single allocation 41 * to handle all possible callers, and given typical object sizes, 42 * the alignment of the buddy allocation will naturally match. 43 */ 44 vaddr = dma_alloc_coherent(obj->base.dev->dev, 45 roundup_pow_of_two(obj->base.size), 46 &dma, GFP_KERNEL); 47 if (!vaddr) 48 return -ENOMEM; 49 50 st = kmalloc(sizeof(*st), GFP_KERNEL); 51 if (!st) 52 goto err_pci; 53 54 if (sg_alloc_table(st, 1, GFP_KERNEL)) 55 goto err_st; 56 57 sg = st->sgl; 58 sg->offset = 0; 59 sg->length = obj->base.size; 60 61 sg_assign_page(sg, (struct page *)vaddr); 62 sg_dma_address(sg) = dma; 63 sg_dma_len(sg) = obj->base.size; 64 65 dst = vaddr; 66 for (i = 0; i < obj->base.size / PAGE_SIZE; i++) { 67 struct page *page; 68 69 page = shmem_read_mapping_page(mapping, i); 70 if (IS_ERR(page)) 71 goto err_st; 72 73 memcpy_from_page(dst, page, 0, PAGE_SIZE); 74 drm_clflush_virt_range(dst, PAGE_SIZE); 75 76 put_page(page); 77 dst += PAGE_SIZE; 78 } 79 80 intel_gt_chipset_flush(to_gt(i915)); 81 82 /* We're no longer struct page backed */ 83 obj->mem_flags &= ~I915_BO_FLAG_STRUCT_PAGE; 84 __i915_gem_object_set_pages(obj, st); 85 86 return 0; 87 88 err_st: 89 kfree(st); 90 err_pci: 91 dma_free_coherent(obj->base.dev->dev, 92 roundup_pow_of_two(obj->base.size), 93 vaddr, dma); 94 return -ENOMEM; 95 } 96 97 void 98 i915_gem_object_put_pages_phys(struct drm_i915_gem_object *obj, 99 struct sg_table *pages) 100 { 101 dma_addr_t dma = sg_dma_address(pages->sgl); 102 void *vaddr = sg_page(pages->sgl); 103 104 __i915_gem_object_release_shmem(obj, pages, false); 105 106 if (obj->mm.dirty) { 107 struct address_space *mapping = obj->base.filp->f_mapping; 108 void *src = vaddr; 109 int i; 110 111 for (i = 0; i < obj->base.size / PAGE_SIZE; i++) { 112 struct page *page; 113 114 page = shmem_read_mapping_page(mapping, i); 115 if (IS_ERR(page)) 116 continue; 117 118 drm_clflush_virt_range(src, PAGE_SIZE); 119 memcpy_to_page(page, 0, src, PAGE_SIZE); 120 121 set_page_dirty(page); 122 if (obj->mm.madv == I915_MADV_WILLNEED) 123 mark_page_accessed(page); 124 put_page(page); 125 126 src += PAGE_SIZE; 127 } 128 obj->mm.dirty = false; 129 } 130 131 sg_free_table(pages); 132 kfree(pages); 133 134 dma_free_coherent(obj->base.dev->dev, 135 roundup_pow_of_two(obj->base.size), 136 vaddr, dma); 137 } 138 139 int i915_gem_object_pwrite_phys(struct drm_i915_gem_object *obj, 140 const struct drm_i915_gem_pwrite *args) 141 { 142 void *vaddr = sg_page(obj->mm.pages->sgl) + args->offset; 143 char __user *user_data = u64_to_user_ptr(args->data_ptr); 144 struct drm_i915_private *i915 = to_i915(obj->base.dev); 145 int err; 146 147 err = i915_gem_object_wait(obj, 148 I915_WAIT_INTERRUPTIBLE | 149 I915_WAIT_ALL, 150 MAX_SCHEDULE_TIMEOUT); 151 if (err) 152 return err; 153 154 /* 155 * We manually control the domain here and pretend that it 156 * remains coherent i.e. in the GTT domain, like shmem_pwrite. 157 */ 158 i915_gem_object_invalidate_frontbuffer(obj, ORIGIN_CPU); 159 160 if (copy_from_user(vaddr, user_data, args->size)) 161 return -EFAULT; 162 163 drm_clflush_virt_range(vaddr, args->size); 164 intel_gt_chipset_flush(to_gt(i915)); 165 166 i915_gem_object_flush_frontbuffer(obj, ORIGIN_CPU); 167 return 0; 168 } 169 170 int i915_gem_object_pread_phys(struct drm_i915_gem_object *obj, 171 const struct drm_i915_gem_pread *args) 172 { 173 void *vaddr = sg_page(obj->mm.pages->sgl) + args->offset; 174 char __user *user_data = u64_to_user_ptr(args->data_ptr); 175 int err; 176 177 err = i915_gem_object_wait(obj, 178 I915_WAIT_INTERRUPTIBLE, 179 MAX_SCHEDULE_TIMEOUT); 180 if (err) 181 return err; 182 183 drm_clflush_virt_range(vaddr, args->size); 184 if (copy_to_user(user_data, vaddr, args->size)) 185 return -EFAULT; 186 187 return 0; 188 } 189 190 static int i915_gem_object_shmem_to_phys(struct drm_i915_gem_object *obj) 191 { 192 struct sg_table *pages; 193 int err; 194 195 pages = __i915_gem_object_unset_pages(obj); 196 197 err = i915_gem_object_get_pages_phys(obj); 198 if (err) 199 goto err_xfer; 200 201 /* Perma-pin (until release) the physical set of pages */ 202 __i915_gem_object_pin_pages(obj); 203 204 if (!IS_ERR_OR_NULL(pages)) 205 i915_gem_object_put_pages_shmem(obj, pages); 206 207 i915_gem_object_release_memory_region(obj); 208 return 0; 209 210 err_xfer: 211 if (!IS_ERR_OR_NULL(pages)) 212 __i915_gem_object_set_pages(obj, pages); 213 return err; 214 } 215 216 int i915_gem_object_attach_phys(struct drm_i915_gem_object *obj, int align) 217 { 218 int err; 219 220 assert_object_held(obj); 221 222 if (align > obj->base.size) 223 return -EINVAL; 224 225 if (!i915_gem_object_is_shmem(obj)) 226 return -EINVAL; 227 228 if (!i915_gem_object_has_struct_page(obj)) 229 return 0; 230 231 err = i915_gem_object_unbind(obj, I915_GEM_OBJECT_UNBIND_ACTIVE); 232 if (err) 233 return err; 234 235 if (obj->mm.madv != I915_MADV_WILLNEED) 236 return -EFAULT; 237 238 if (i915_gem_object_has_tiling_quirk(obj)) 239 return -EFAULT; 240 241 if (obj->mm.mapping || i915_gem_object_has_pinned_pages(obj)) 242 return -EBUSY; 243 244 if (unlikely(obj->mm.madv != I915_MADV_WILLNEED)) { 245 drm_dbg(obj->base.dev, 246 "Attempting to obtain a purgeable object\n"); 247 return -EFAULT; 248 } 249 250 return i915_gem_object_shmem_to_phys(obj); 251 } 252 253 #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST) 254 #include "selftests/i915_gem_phys.c" 255 #endif 256