drivers/gpu/drm/i915/gem/i915_gem_phys.c

   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