drivers/gpu/drm/armada/armada_gem.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2012 Russell King
   4  */
   5
   6 #include <linux/dma-buf.h>
   7 #include <linux/dma-mapping.h>
   8 #include <linux/mman.h>
   9 #include <linux/shmem_fs.h>
  10
  11 #include <drm/armada_drm.h>
  12 #include <drm/drm_prime.h>
  13
  14 #include "armada_drm.h"
  15 #include "armada_gem.h"
  16 #include "armada_ioctlP.h"
  17
  18 static vm_fault_t armada_gem_vm_fault(struct vm_fault *vmf)
  19 {
  20         struct drm_gem_object *gobj = vmf->vma->vm_private_data;
  21         struct armada_gem_object *obj = drm_to_armada_gem(gobj);
  22         unsigned long pfn = obj->phys_addr >> PAGE_SHIFT;
  23
  24         pfn += (vmf->address - vmf->vma->vm_start) >> PAGE_SHIFT;
  25         return vmf_insert_pfn(vmf->vma, vmf->address, pfn);
  26 }
  27
  28 static const struct vm_operations_struct armada_gem_vm_ops = {
  29         .fault  = armada_gem_vm_fault,
  30         .open   = drm_gem_vm_open,
  31         .close  = drm_gem_vm_close,
  32 };
  33
  34 static size_t roundup_gem_size(size_t size)
  35 {
  36         return roundup(size, PAGE_SIZE);
  37 }
  38
  39 void armada_gem_free_object(struct drm_gem_object *obj)
  40 {
  41         struct armada_gem_object *dobj = drm_to_armada_gem(obj);
  42         struct armada_private *priv = drm_to_armada_dev(obj->dev);
  43
  44         DRM_DEBUG_DRIVER("release obj %p\n", dobj);
  45
  46         drm_gem_free_mmap_offset(&dobj->obj);
  47
  48         might_lock(&priv->linear_lock);
  49
  50         if (dobj->page) {
  51                 /* page backed memory */
  52                 unsigned int order = get_order(dobj->obj.size);
  53                 __free_pages(dobj->page, order);
  54         } else if (dobj->linear) {
  55                 /* linear backed memory */
  56                 mutex_lock(&priv->linear_lock);
  57                 drm_mm_remove_node(dobj->linear);
  58                 mutex_unlock(&priv->linear_lock);
  59                 kfree(dobj->linear);
  60                 if (dobj->addr)
  61                         iounmap(dobj->addr);
  62         }
  63
  64         if (dobj->obj.import_attach) {
  65                 /* We only ever display imported data */
  66                 if (dobj->sgt)
  67                         dma_buf_unmap_attachment(dobj->obj.import_attach,
  68                                                  dobj->sgt, DMA_TO_DEVICE);
  69                 drm_prime_gem_destroy(&dobj->obj, NULL);
  70         }
  71
  72         drm_gem_object_release(&dobj->obj);
  73
  74         kfree(dobj);
  75 }
  76
  77 int
  78 armada_gem_linear_back(struct drm_device *dev, struct armada_gem_object *obj)
  79 {
  80         struct armada_private *priv = drm_to_armada_dev(dev);
  81         size_t size = obj->obj.size;
  82
  83         if (obj->page || obj->linear)
  84                 return 0;
  85
  86         /*
  87          * If it is a small allocation (typically cursor, which will
  88          * be 32x64 or 64x32 ARGB pixels) try to get it from the system.
  89          * Framebuffers will never be this small (our minimum size for
  90          * framebuffers is larger than this anyway.)  Such objects are
  91          * only accessed by the CPU so we don't need any special handing
  92          * here.
  93          */
  94         if (size <= 8192) {
  95                 unsigned int order = get_order(size);
  96                 struct page *p = alloc_pages(GFP_KERNEL, order);
  97
  98                 if (p) {
  99                         obj->addr = page_address(p);
 100                         obj->phys_addr = page_to_phys(p);
 101                         obj->page = p;
 102
 103                         memset(obj->addr, 0, PAGE_ALIGN(size));
 104                 }
 105         }
 106
 107         /*
 108          * We could grab something from CMA if it's enabled, but that
 109          * involves building in a problem:
 110          *
 111          * CMA's interface uses dma_alloc_coherent(), which provides us
 112          * with an CPU virtual address and a device address.
 113          *
 114          * The CPU virtual address may be either an address in the kernel
 115          * direct mapped region (for example, as it would be on x86) or
 116          * it may be remapped into another part of kernel memory space
 117          * (eg, as it would be on ARM.)  This means virt_to_phys() on the
 118          * returned virtual address is invalid depending on the architecture
 119          * implementation.
 120          *
 121          * The device address may also not be a physical address; it may
 122          * be that there is some kind of remapping between the device and
 123          * system RAM, which makes the use of the device address also
 124          * unsafe to re-use as a physical address.
 125          *
 126          * This makes DRM usage of dma_alloc_coherent() in a generic way
 127          * at best very questionable and unsafe.
 128          */
 129
 130         /* Otherwise, grab it from our linear allocation */
 131         if (!obj->page) {
 132                 struct drm_mm_node *node;
 133                 unsigned align = min_t(unsigned, size, SZ_2M);
 134                 void __iomem *ptr;
 135                 int ret;
 136
 137                 node = kzalloc(sizeof(*node), GFP_KERNEL);
 138                 if (!node)
 139                         return -ENOSPC;
 140
 141                 mutex_lock(&priv->linear_lock);
 142                 ret = drm_mm_insert_node_generic(&priv->linear, node,
 143                                                  size, align, 0, 0);
 144                 mutex_unlock(&priv->linear_lock);
 145                 if (ret) {
 146                         kfree(node);
 147                         return ret;
 148                 }
 149
 150                 obj->linear = node;
 151
 152                 /* Ensure that the memory we're returning is cleared. */
 153                 ptr = ioremap_wc(obj->linear->start, size);
 154                 if (!ptr) {
 155                         mutex_lock(&priv->linear_lock);
 156                         drm_mm_remove_node(obj->linear);
 157                         mutex_unlock(&priv->linear_lock);
 158                         kfree(obj->linear);
 159                         obj->linear = NULL;
 160                         return -ENOMEM;
 161                 }
 162
 163                 memset_io(ptr, 0, size);
 164                 iounmap(ptr);
 165
 166                 obj->phys_addr = obj->linear->start;
 167                 obj->dev_addr = obj->linear->start;
 168                 obj->mapped = true;
 169         }
 170
 171         DRM_DEBUG_DRIVER("obj %p phys %#llx dev %#llx\n", obj,
 172                          (unsigned long long)obj->phys_addr,
 173                          (unsigned long long)obj->dev_addr);
 174
 175         return 0;
 176 }
 177
 178 void *
 179 armada_gem_map_object(struct drm_device *dev, struct armada_gem_object *dobj)
 180 {
 181         /* only linear objects need to be ioremap'd */
 182         if (!dobj->addr && dobj->linear)
 183                 dobj->addr = ioremap_wc(dobj->phys_addr, dobj->obj.size);
 184         return dobj->addr;
 185 }
 186
 187 static const struct drm_gem_object_funcs armada_gem_object_funcs = {
 188         .free = armada_gem_free_object,
 189         .export = armada_gem_prime_export,
 190         .vm_ops = &armada_gem_vm_ops,
 191 };
 192
 193 struct armada_gem_object *
 194 armada_gem_alloc_private_object(struct drm_device *dev, size_t size)
 195 {
 196         struct armada_gem_object *obj;
 197
 198         size = roundup_gem_size(size);
 199
 200         obj = kzalloc(sizeof(*obj), GFP_KERNEL);
 201         if (!obj)
 202                 return NULL;
 203
 204         obj->obj.funcs = &armada_gem_object_funcs;
 205
 206         drm_gem_private_object_init(dev, &obj->obj, size);
 207
 208         DRM_DEBUG_DRIVER("alloc private obj %p size %zu\n", obj, size);
 209
 210         return obj;
 211 }
 212
 213 static struct armada_gem_object *armada_gem_alloc_object(struct drm_device *dev,
 214         size_t size)
 215 {
 216         struct armada_gem_object *obj;
 217         struct address_space *mapping;
 218
 219         size = roundup_gem_size(size);
 220
 221         obj = kzalloc(sizeof(*obj), GFP_KERNEL);
 222         if (!obj)
 223                 return NULL;
 224
 225         obj->obj.funcs = &armada_gem_object_funcs;
 226
 227         if (drm_gem_object_init(dev, &obj->obj, size)) {
 228                 kfree(obj);
 229                 return NULL;
 230         }
 231
 232         mapping = obj->obj.filp->f_mapping;
 233         mapping_set_gfp_mask(mapping, GFP_HIGHUSER | __GFP_RECLAIMABLE);
 234
 235         DRM_DEBUG_DRIVER("alloc obj %p size %zu\n", obj, size);
 236
 237         return obj;
 238 }
 239
 240 /* Dumb alloc support */
 241 int armada_gem_dumb_create(struct drm_file *file, struct drm_device *dev,
 242         struct drm_mode_create_dumb *args)
 243 {
 244         struct armada_gem_object *dobj;
 245         u32 handle;
 246         size_t size;
 247         int ret;
 248
 249         args->pitch = armada_pitch(args->width, args->bpp);
 250         args->size = size = args->pitch * args->height;
 251
 252         dobj = armada_gem_alloc_private_object(dev, size);
 253         if (dobj == NULL)
 254                 return -ENOMEM;
 255
 256         ret = armada_gem_linear_back(dev, dobj);
 257         if (ret)
 258                 goto err;
 259
 260         ret = drm_gem_handle_create(file, &dobj->obj, &handle);
 261         if (ret)
 262                 goto err;
 263
 264         args->handle = handle;
 265
 266         /* drop reference from allocate - handle holds it now */
 267         DRM_DEBUG_DRIVER("obj %p size %zu handle %#x\n", dobj, size, handle);
 268  err:
 269         drm_gem_object_put(&dobj->obj);
 270         return ret;
 271 }
 272
 273 /* Private driver gem ioctls */
 274 int armada_gem_create_ioctl(struct drm_device *dev, void *data,
 275         struct drm_file *file)
 276 {
 277         struct drm_armada_gem_create *args = data;
 278         struct armada_gem_object *dobj;
 279         size_t size;
 280         u32 handle;
 281         int ret;
 282
 283         if (args->size == 0)
 284                 return -ENOMEM;
 285
 286         size = args->size;
 287
 288         dobj = armada_gem_alloc_object(dev, size);
 289         if (dobj == NULL)
 290                 return -ENOMEM;
 291
 292         ret = drm_gem_handle_create(file, &dobj->obj, &handle);
 293         if (ret)
 294                 goto err;
 295
 296         args->handle = handle;
 297
 298         /* drop reference from allocate - handle holds it now */
 299         DRM_DEBUG_DRIVER("obj %p size %zu handle %#x\n", dobj, size, handle);
 300  err:
 301         drm_gem_object_put(&dobj->obj);
 302         return ret;
 303 }
 304
 305 /* Map a shmem-backed object into process memory space */
 306 int armada_gem_mmap_ioctl(struct drm_device *dev, void *data,
 307         struct drm_file *file)
 308 {
 309         struct drm_armada_gem_mmap *args = data;
 310         struct armada_gem_object *dobj;
 311         unsigned long addr;
 312
 313         dobj = armada_gem_object_lookup(file, args->handle);
 314         if (dobj == NULL)
 315                 return -ENOENT;
 316
 317         if (!dobj->obj.filp) {
 318                 drm_gem_object_put(&dobj->obj);
 319                 return -EINVAL;
 320         }
 321
 322         addr = vm_mmap(dobj->obj.filp, 0, args->size, PROT_READ | PROT_WRITE,
 323                        MAP_SHARED, args->offset);
 324         drm_gem_object_put(&dobj->obj);
 325         if (IS_ERR_VALUE(addr))
 326                 return addr;
 327
 328         args->addr = addr;
 329
 330         return 0;
 331 }
 332
 333 int armada_gem_pwrite_ioctl(struct drm_device *dev, void *data,
 334         struct drm_file *file)
 335 {
 336         struct drm_armada_gem_pwrite *args = data;
 337         struct armada_gem_object *dobj;
 338         char __user *ptr;
 339         int ret;
 340
 341         DRM_DEBUG_DRIVER("handle %u off %u size %u ptr 0x%llx\n",
 342                 args->handle, args->offset, args->size, args->ptr);
 343
 344         if (args->size == 0)
 345                 return 0;
 346
 347         ptr = (char __user *)(uintptr_t)args->ptr;
 348
 349         if (!access_ok(ptr, args->size))
 350                 return -EFAULT;
 351
 352         ret = fault_in_pages_readable(ptr, args->size);
 353         if (ret)
 354                 return ret;
 355
 356         dobj = armada_gem_object_lookup(file, args->handle);
 357         if (dobj == NULL)
 358                 return -ENOENT;
 359
 360         /* Must be a kernel-mapped object */
 361         if (!dobj->addr)
 362                 return -EINVAL;
 363
 364         if (args->offset > dobj->obj.size ||
 365             args->size > dobj->obj.size - args->offset) {
 366                 DRM_ERROR("invalid size: object size %u\n", dobj->obj.size);
 367                 ret = -EINVAL;
 368                 goto unref;
 369         }
 370
 371         if (copy_from_user(dobj->addr + args->offset, ptr, args->size)) {
 372                 ret = -EFAULT;
 373         } else if (dobj->update) {
 374                 dobj->update(dobj->update_data);
 375                 ret = 0;
 376         }
 377
 378  unref:
 379         drm_gem_object_put(&dobj->obj);
 380         return ret;
 381 }
 382
 383 /* Prime support */
 384 static struct sg_table *
 385 armada_gem_prime_map_dma_buf(struct dma_buf_attachment *attach,
 386         enum dma_data_direction dir)
 387 {
 388         struct drm_gem_object *obj = attach->dmabuf->priv;
 389         struct armada_gem_object *dobj = drm_to_armada_gem(obj);
 390         struct scatterlist *sg;
 391         struct sg_table *sgt;
 392         int i;
 393
 394         sgt = kmalloc(sizeof(*sgt), GFP_KERNEL);
 395         if (!sgt)
 396                 return NULL;
 397
 398         if (dobj->obj.filp) {
 399                 struct address_space *mapping;
 400                 int count;
 401
 402                 count = dobj->obj.size / PAGE_SIZE;
 403                 if (sg_alloc_table(sgt, count, GFP_KERNEL))
 404                         goto free_sgt;
 405
 406                 mapping = dobj->obj.filp->f_mapping;
 407
 408                 for_each_sgtable_sg(sgt, sg, i) {
 409                         struct page *page;
 410
 411                         page = shmem_read_mapping_page(mapping, i);
 412                         if (IS_ERR(page))
 413                                 goto release;
 414
 415                         sg_set_page(sg, page, PAGE_SIZE, 0);
 416                 }
 417
 418                 if (dma_map_sgtable(attach->dev, sgt, dir, 0))
 419                         goto release;
 420         } else if (dobj->page) {
 421                 /* Single contiguous page */
 422                 if (sg_alloc_table(sgt, 1, GFP_KERNEL))
 423                         goto free_sgt;
 424
 425                 sg_set_page(sgt->sgl, dobj->page, dobj->obj.size, 0);
 426
 427                 if (dma_map_sgtable(attach->dev, sgt, dir, 0))
 428                         goto free_table;
 429         } else if (dobj->linear) {
 430                 /* Single contiguous physical region - no struct page */
 431                 if (sg_alloc_table(sgt, 1, GFP_KERNEL))
 432                         goto free_sgt;
 433                 sg_dma_address(sgt->sgl) = dobj->dev_addr;
 434                 sg_dma_len(sgt->sgl) = dobj->obj.size;
 435         } else {
 436                 goto free_sgt;
 437         }
 438         return sgt;
 439
 440  release:
 441         for_each_sgtable_sg(sgt, sg, i)
 442                 if (sg_page(sg))
 443                         put_page(sg_page(sg));
 444  free_table:
 445         sg_free_table(sgt);
 446  free_sgt:
 447         kfree(sgt);
 448         return NULL;
 449 }
 450
 451 static void armada_gem_prime_unmap_dma_buf(struct dma_buf_attachment *attach,
 452         struct sg_table *sgt, enum dma_data_direction dir)
 453 {
 454         struct drm_gem_object *obj = attach->dmabuf->priv;
 455         struct armada_gem_object *dobj = drm_to_armada_gem(obj);
 456         int i;
 457
 458         if (!dobj->linear)
 459                 dma_unmap_sgtable(attach->dev, sgt, dir, 0);
 460
 461         if (dobj->obj.filp) {
 462                 struct scatterlist *sg;
 463
 464                 for_each_sgtable_sg(sgt, sg, i)
 465                         put_page(sg_page(sg));
 466         }
 467
 468         sg_free_table(sgt);
 469         kfree(sgt);
 470 }
 471
 472 static int
 473 armada_gem_dmabuf_mmap(struct dma_buf *buf, struct vm_area_struct *vma)
 474 {
 475         return -EINVAL;
 476 }
 477
 478 static const struct dma_buf_ops armada_gem_prime_dmabuf_ops = {
 479         .map_dma_buf    = armada_gem_prime_map_dma_buf,
 480         .unmap_dma_buf  = armada_gem_prime_unmap_dma_buf,
 481         .release        = drm_gem_dmabuf_release,
 482         .mmap           = armada_gem_dmabuf_mmap,
 483 };
 484
 485 struct dma_buf *
 486 armada_gem_prime_export(struct drm_gem_object *obj, int flags)
 487 {
 488         DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
 489
 490         exp_info.ops = &armada_gem_prime_dmabuf_ops;
 491         exp_info.size = obj->size;
 492         exp_info.flags = O_RDWR;
 493         exp_info.priv = obj;
 494
 495         return drm_gem_dmabuf_export(obj->dev, &exp_info);
 496 }
 497
 498 struct drm_gem_object *
 499 armada_gem_prime_import(struct drm_device *dev, struct dma_buf *buf)
 500 {
 501         struct dma_buf_attachment *attach;
 502         struct armada_gem_object *dobj;
 503
 504         if (buf->ops == &armada_gem_prime_dmabuf_ops) {
 505                 struct drm_gem_object *obj = buf->priv;
 506                 if (obj->dev == dev) {
 507                         /*
 508                          * Importing our own dmabuf(s) increases the
 509                          * refcount on the gem object itself.
 510                          */
 511                         drm_gem_object_get(obj);
 512                         return obj;
 513                 }
 514         }
 515
 516         attach = dma_buf_attach(buf, dev->dev);
 517         if (IS_ERR(attach))
 518                 return ERR_CAST(attach);
 519
 520         dobj = armada_gem_alloc_private_object(dev, buf->size);
 521         if (!dobj) {
 522                 dma_buf_detach(buf, attach);
 523                 return ERR_PTR(-ENOMEM);
 524         }
 525
 526         dobj->obj.import_attach = attach;
 527         get_dma_buf(buf);
 528
 529         /*
 530          * Don't call dma_buf_map_attachment() here - it maps the
 531          * scatterlist immediately for DMA, and this is not always
 532          * an appropriate thing to do.
 533          */
 534         return &dobj->obj;
 535 }
 536
 537 int armada_gem_map_import(struct armada_gem_object *dobj)
 538 {
 539         int ret;
 540
 541         dobj->sgt = dma_buf_map_attachment(dobj->obj.import_attach,
 542                                            DMA_TO_DEVICE);
 543         if (IS_ERR(dobj->sgt)) {
 544                 ret = PTR_ERR(dobj->sgt);
 545                 dobj->sgt = NULL;
 546                 DRM_ERROR("dma_buf_map_attachment() error: %d\n", ret);
 547                 return ret;
 548         }
 549         if (dobj->sgt->nents > 1) {
 550                 DRM_ERROR("dma_buf_map_attachment() returned an (unsupported) scattered list\n");
 551                 return -EINVAL;
 552         }
 553         if (sg_dma_len(dobj->sgt->sgl) < dobj->obj.size) {
 554                 DRM_ERROR("dma_buf_map_attachment() returned a small buffer\n");
 555                 return -EINVAL;
 556         }
 557         dobj->dev_addr = sg_dma_address(dobj->sgt->sgl);
 558         dobj->mapped = true;
 559         return 0;
 560 }