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.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