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 void *src; 69 70 page = shmem_read_mapping_page(mapping, i); 71 if (IS_ERR(page)) 72 goto err_st; 73 74 src = kmap_atomic(page); 75 memcpy(dst, src, PAGE_SIZE); 76 drm_clflush_virt_range(dst, PAGE_SIZE); 77 kunmap_atomic(src); 78 79 put_page(page); 80 dst += PAGE_SIZE; 81 } 82 83 intel_gt_chipset_flush(to_gt(i915)); 84 85 /* We're no longer struct page backed */ 86 obj->mem_flags &= ~I915_BO_FLAG_STRUCT_PAGE; 87 __i915_gem_object_set_pages(obj, st); 88 89 return 0; 90 91 err_st: 92 kfree(st); 93 err_pci: 94 dma_free_coherent(obj->base.dev->dev, 95 roundup_pow_of_two(obj->base.size), 96 vaddr, dma); 97 return -ENOMEM; 98 } 99 100 void 101 i915_gem_object_put_pages_phys(struct drm_i915_gem_object *obj, 102 struct sg_table *pages) 103 { 104 dma_addr_t dma = sg_dma_address(pages->sgl); 105 void *vaddr = sg_page(pages->sgl); 106 107 __i915_gem_object_release_shmem(obj, pages, false); 108 109 if (obj->mm.dirty) { 110 struct address_space *mapping = obj->base.filp->f_mapping; 111 void *src = vaddr; 112 int i; 113 114 for (i = 0; i < obj->base.size / PAGE_SIZE; i++) { 115 struct page *page; 116 char *dst; 117 118 page = shmem_read_mapping_page(mapping, i); 119 if (IS_ERR(page)) 120 continue; 121 122 dst = kmap_atomic(page); 123 drm_clflush_virt_range(src, PAGE_SIZE); 124 memcpy(dst, src, PAGE_SIZE); 125 kunmap_atomic(dst); 126 127 set_page_dirty(page); 128 if (obj->mm.madv == I915_MADV_WILLNEED) 129 mark_page_accessed(page); 130 put_page(page); 131 132 src += PAGE_SIZE; 133 } 134 obj->mm.dirty = false; 135 } 136 137 sg_free_table(pages); 138 kfree(pages); 139 140 dma_free_coherent(obj->base.dev->dev, 141 roundup_pow_of_two(obj->base.size), 142 vaddr, dma); 143 } 144 145 int i915_gem_object_pwrite_phys(struct drm_i915_gem_object *obj, 146 const struct drm_i915_gem_pwrite *args) 147 { 148 void *vaddr = sg_page(obj->mm.pages->sgl) + args->offset; 149 char __user *user_data = u64_to_user_ptr(args->data_ptr); 150 struct drm_i915_private *i915 = to_i915(obj->base.dev); 151 int err; 152 153 err = i915_gem_object_wait(obj, 154 I915_WAIT_INTERRUPTIBLE | 155 I915_WAIT_ALL, 156 MAX_SCHEDULE_TIMEOUT); 157 if (err) 158 return err; 159 160 /* 161 * We manually control the domain here and pretend that it 162 * remains coherent i.e. in the GTT domain, like shmem_pwrite. 163 */ 164 i915_gem_object_invalidate_frontbuffer(obj, ORIGIN_CPU); 165 166 if (copy_from_user(vaddr, user_data, args->size)) 167 return -EFAULT; 168 169 drm_clflush_virt_range(vaddr, args->size); 170 intel_gt_chipset_flush(to_gt(i915)); 171 172 i915_gem_object_flush_frontbuffer(obj, ORIGIN_CPU); 173 return 0; 174 } 175 176 int i915_gem_object_pread_phys(struct drm_i915_gem_object *obj, 177 const struct drm_i915_gem_pread *args) 178 { 179 void *vaddr = sg_page(obj->mm.pages->sgl) + args->offset; 180 char __user *user_data = u64_to_user_ptr(args->data_ptr); 181 int err; 182 183 err = i915_gem_object_wait(obj, 184 I915_WAIT_INTERRUPTIBLE, 185 MAX_SCHEDULE_TIMEOUT); 186 if (err) 187 return err; 188 189 drm_clflush_virt_range(vaddr, args->size); 190 if (copy_to_user(user_data, vaddr, args->size)) 191 return -EFAULT; 192 193 return 0; 194 } 195 196 static int i915_gem_object_shmem_to_phys(struct drm_i915_gem_object *obj) 197 { 198 struct sg_table *pages; 199 int err; 200 201 pages = __i915_gem_object_unset_pages(obj); 202 203 err = i915_gem_object_get_pages_phys(obj); 204 if (err) 205 goto err_xfer; 206 207 /* Perma-pin (until release) the physical set of pages */ 208 __i915_gem_object_pin_pages(obj); 209 210 if (!IS_ERR_OR_NULL(pages)) 211 i915_gem_object_put_pages_shmem(obj, pages); 212 213 i915_gem_object_release_memory_region(obj); 214 return 0; 215 216 err_xfer: 217 if (!IS_ERR_OR_NULL(pages)) 218 __i915_gem_object_set_pages(obj, pages); 219 return err; 220 } 221 222 int i915_gem_object_attach_phys(struct drm_i915_gem_object *obj, int align) 223 { 224 int err; 225 226 assert_object_held(obj); 227 228 if (align > obj->base.size) 229 return -EINVAL; 230 231 if (!i915_gem_object_is_shmem(obj)) 232 return -EINVAL; 233 234 if (!i915_gem_object_has_struct_page(obj)) 235 return 0; 236 237 err = i915_gem_object_unbind(obj, I915_GEM_OBJECT_UNBIND_ACTIVE); 238 if (err) 239 return err; 240 241 if (obj->mm.madv != I915_MADV_WILLNEED) 242 return -EFAULT; 243 244 if (i915_gem_object_has_tiling_quirk(obj)) 245 return -EFAULT; 246 247 if (obj->mm.mapping || i915_gem_object_has_pinned_pages(obj)) 248 return -EBUSY; 249 250 if (unlikely(obj->mm.madv != I915_MADV_WILLNEED)) { 251 drm_dbg(obj->base.dev, 252 "Attempting to obtain a purgeable object\n"); 253 return -EFAULT; 254 } 255 256 return i915_gem_object_shmem_to_phys(obj); 257 } 258 259 #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST) 260 #include "selftests/i915_gem_phys.c" 261 #endif 262