drivers/gpu/drm/vgem/vgem_drv.c

   1 /*
   2  * Copyright 2011 Red Hat, Inc.
   3  * Copyright © 2014 The Chromium OS Authors
   4  *
   5  * Permission is hereby granted, free of charge, to any person obtaining a
   6  * copy of this software and associated documentation files (the "Software")
   7  * to deal in the software without restriction, including without limitation
   8  * on the rights to use, copy, modify, merge, publish, distribute, sub
   9  * license, and/or sell copies of the Software, and to permit persons to whom
  10  * them Software is furnished to do so, subject to the following conditions:
  11  *
  12  * The above copyright notice and this permission notice (including the next
  13  * paragraph) shall be included in all copies or substantial portions of the
  14  * Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTIBILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.  IN NO EVENT SHALL
  19  * THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES, OR OTHER LIABILITY, WHETHER
  20  * IN AN ACTION OF CONTRACT, TORT, OR OTHERWISE, ARISING FROM, OUT OF OR IN
  21  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  22  *
  23  * Authors:
  24  *      Adam Jackson <ajax@redhat.com>
  25  *      Ben Widawsky <ben@bwidawsk.net>
  26  */
  27
  28 /**
  29  * This is vgem, a (non-hardware-backed) GEM service.  This is used by Mesa's
  30  * software renderer and the X server for efficient buffer sharing.
  31  */
  32
  33 #include <linux/module.h>
  34 #include <linux/ramfs.h>
  35 #include <linux/shmem_fs.h>
  36 #include <linux/dma-buf.h>
  37 #include "vgem_drv.h"
  38
  39 #define DRIVER_NAME     "vgem"
  40 #define DRIVER_DESC     "Virtual GEM provider"
  41 #define DRIVER_DATE     "20120112"
  42 #define DRIVER_MAJOR    1
  43 #define DRIVER_MINOR    0
  44
  45 static struct vgem_device {
  46         struct drm_device drm;
  47         struct platform_device *platform;
  48 } *vgem_device;
  49
  50 static void vgem_gem_free_object(struct drm_gem_object *obj)
  51 {
  52         struct drm_vgem_gem_object *vgem_obj = to_vgem_bo(obj);
  53
  54         kvfree(vgem_obj->pages);
  55
  56         if (obj->import_attach)
  57                 drm_prime_gem_destroy(obj, vgem_obj->table);
  58
  59         drm_gem_object_release(obj);
  60         kfree(vgem_obj);
  61 }
  62
  63 static int vgem_gem_fault(struct vm_fault *vmf)
  64 {
  65         struct vm_area_struct *vma = vmf->vma;
  66         struct drm_vgem_gem_object *obj = vma->vm_private_data;
  67         /* We don't use vmf->pgoff since that has the fake offset */
  68         unsigned long vaddr = vmf->address;
  69         int ret;
  70         loff_t num_pages;
  71         pgoff_t page_offset;
  72         page_offset = (vaddr - vma->vm_start) >> PAGE_SHIFT;
  73
  74         num_pages = DIV_ROUND_UP(obj->base.size, PAGE_SIZE);
  75
  76         if (page_offset > num_pages)
  77                 return VM_FAULT_SIGBUS;
  78
  79         if (obj->pages) {
  80                 get_page(obj->pages[page_offset]);
  81                 vmf->page = obj->pages[page_offset];
  82                 ret = 0;
  83         } else {
  84                 struct page *page;
  85
  86                 page = shmem_read_mapping_page(
  87                                         file_inode(obj->base.filp)->i_mapping,
  88                                         page_offset);
  89                 if (!IS_ERR(page)) {
  90                         vmf->page = page;
  91                         ret = 0;
  92                 } else switch (PTR_ERR(page)) {
  93                         case -ENOSPC:
  94                         case -ENOMEM:
  95                                 ret = VM_FAULT_OOM;
  96                                 break;
  97                         case -EBUSY:
  98                                 ret = VM_FAULT_RETRY;
  99                                 break;
 100                         case -EFAULT:
 101                         case -EINVAL:
 102                                 ret = VM_FAULT_SIGBUS;
 103                                 break;
 104                         default:
 105                                 WARN_ON(PTR_ERR(page));
 106                                 ret = VM_FAULT_SIGBUS;
 107                                 break;
 108                 }
 109
 110         }
 111         return ret;
 112 }
 113
 114 static const struct vm_operations_struct vgem_gem_vm_ops = {
 115         .fault = vgem_gem_fault,
 116         .open = drm_gem_vm_open,
 117         .close = drm_gem_vm_close,
 118 };
 119
 120 static int vgem_open(struct drm_device *dev, struct drm_file *file)
 121 {
 122         struct vgem_file *vfile;
 123         int ret;
 124
 125         vfile = kzalloc(sizeof(*vfile), GFP_KERNEL);
 126         if (!vfile)
 127                 return -ENOMEM;
 128
 129         file->driver_priv = vfile;
 130
 131         ret = vgem_fence_open(vfile);
 132         if (ret) {
 133                 kfree(vfile);
 134                 return ret;
 135         }
 136
 137         return 0;
 138 }
 139
 140 static void vgem_postclose(struct drm_device *dev, struct drm_file *file)
 141 {
 142         struct vgem_file *vfile = file->driver_priv;
 143
 144         vgem_fence_close(vfile);
 145         kfree(vfile);
 146 }
 147
 148 static struct drm_vgem_gem_object *__vgem_gem_create(struct drm_device *dev,
 149                                                 unsigned long size)
 150 {
 151         struct drm_vgem_gem_object *obj;
 152         int ret;
 153
 154         obj = kzalloc(sizeof(*obj), GFP_KERNEL);
 155         if (!obj)
 156                 return ERR_PTR(-ENOMEM);
 157
 158         ret = drm_gem_object_init(dev, &obj->base, roundup(size, PAGE_SIZE));
 159         if (ret) {
 160                 kfree(obj);
 161                 return ERR_PTR(ret);
 162         }
 163
 164         return obj;
 165 }
 166
 167 static void __vgem_gem_destroy(struct drm_vgem_gem_object *obj)
 168 {
 169         drm_gem_object_release(&obj->base);
 170         kfree(obj);
 171 }
 172
 173 static struct drm_gem_object *vgem_gem_create(struct drm_device *dev,
 174                                               struct drm_file *file,
 175                                               unsigned int *handle,
 176                                               unsigned long size)
 177 {
 178         struct drm_vgem_gem_object *obj;
 179         int ret;
 180
 181         obj = __vgem_gem_create(dev, size);
 182         if (IS_ERR(obj))
 183                 return ERR_CAST(obj);
 184
 185         ret = drm_gem_handle_create(file, &obj->base, handle);
 186         drm_gem_object_unreference_unlocked(&obj->base);
 187         if (ret)
 188                 goto err;
 189
 190         return &obj->base;
 191
 192 err:
 193         __vgem_gem_destroy(obj);
 194         return ERR_PTR(ret);
 195 }
 196
 197 static int vgem_gem_dumb_create(struct drm_file *file, struct drm_device *dev,
 198                                 struct drm_mode_create_dumb *args)
 199 {
 200         struct drm_gem_object *gem_object;
 201         u64 pitch, size;
 202
 203         pitch = args->width * DIV_ROUND_UP(args->bpp, 8);
 204         size = args->height * pitch;
 205         if (size == 0)
 206                 return -EINVAL;
 207
 208         gem_object = vgem_gem_create(dev, file, &args->handle, size);
 209         if (IS_ERR(gem_object))
 210                 return PTR_ERR(gem_object);
 211
 212         args->size = gem_object->size;
 213         args->pitch = pitch;
 214
 215         DRM_DEBUG_DRIVER("Created object of size %lld\n", size);
 216
 217         return 0;
 218 }
 219
 220 static int vgem_gem_dumb_map(struct drm_file *file, struct drm_device *dev,
 221                              uint32_t handle, uint64_t *offset)
 222 {
 223         struct drm_gem_object *obj;
 224         int ret;
 225
 226         obj = drm_gem_object_lookup(file, handle);
 227         if (!obj)
 228                 return -ENOENT;
 229
 230         if (!obj->filp) {
 231                 ret = -EINVAL;
 232                 goto unref;
 233         }
 234
 235         ret = drm_gem_create_mmap_offset(obj);
 236         if (ret)
 237                 goto unref;
 238
 239         *offset = drm_vma_node_offset_addr(&obj->vma_node);
 240 unref:
 241         drm_gem_object_unreference_unlocked(obj);
 242
 243         return ret;
 244 }
 245
 246 static struct drm_ioctl_desc vgem_ioctls[] = {
 247         DRM_IOCTL_DEF_DRV(VGEM_FENCE_ATTACH, vgem_fence_attach_ioctl, DRM_AUTH|DRM_RENDER_ALLOW),
 248         DRM_IOCTL_DEF_DRV(VGEM_FENCE_SIGNAL, vgem_fence_signal_ioctl, DRM_AUTH|DRM_RENDER_ALLOW),
 249 };
 250
 251 static int vgem_mmap(struct file *filp, struct vm_area_struct *vma)
 252 {
 253         unsigned long flags = vma->vm_flags;
 254         int ret;
 255
 256         ret = drm_gem_mmap(filp, vma);
 257         if (ret)
 258                 return ret;
 259
 260         /* Keep the WC mmaping set by drm_gem_mmap() but our pages
 261          * are ordinary and not special.
 262          */
 263         vma->vm_flags = flags | VM_DONTEXPAND | VM_DONTDUMP;
 264         return 0;
 265 }
 266
 267 static const struct file_operations vgem_driver_fops = {
 268         .owner          = THIS_MODULE,
 269         .open           = drm_open,
 270         .mmap           = vgem_mmap,
 271         .poll           = drm_poll,
 272         .read           = drm_read,
 273         .unlocked_ioctl = drm_ioctl,
 274         .release        = drm_release,
 275 };
 276
 277 static int vgem_prime_pin(struct drm_gem_object *obj)
 278 {
 279         long n_pages = obj->size >> PAGE_SHIFT;
 280         struct page **pages;
 281
 282         /* Flush the object from the CPU cache so that importers can rely
 283          * on coherent indirect access via the exported dma-address.
 284          */
 285         pages = drm_gem_get_pages(obj);
 286         if (IS_ERR(pages))
 287                 return PTR_ERR(pages);
 288
 289         drm_clflush_pages(pages, n_pages);
 290         drm_gem_put_pages(obj, pages, true, false);
 291
 292         return 0;
 293 }
 294
 295 static struct sg_table *vgem_prime_get_sg_table(struct drm_gem_object *obj)
 296 {
 297         struct sg_table *st;
 298         struct page **pages;
 299
 300         pages = drm_gem_get_pages(obj);
 301         if (IS_ERR(pages))
 302                 return ERR_CAST(pages);
 303
 304         st = drm_prime_pages_to_sg(pages, obj->size >> PAGE_SHIFT);
 305         drm_gem_put_pages(obj, pages, false, false);
 306
 307         return st;
 308 }
 309
 310 static struct drm_gem_object* vgem_prime_import(struct drm_device *dev,
 311                                                 struct dma_buf *dma_buf)
 312 {
 313         struct vgem_device *vgem = container_of(dev, typeof(*vgem), drm);
 314
 315         return drm_gem_prime_import_dev(dev, dma_buf, &vgem->platform->dev);
 316 }
 317
 318 static struct drm_gem_object *vgem_prime_import_sg_table(struct drm_device *dev,
 319                         struct dma_buf_attachment *attach, struct sg_table *sg)
 320 {
 321         struct drm_vgem_gem_object *obj;
 322         int npages;
 323
 324         obj = __vgem_gem_create(dev, attach->dmabuf->size);
 325         if (IS_ERR(obj))
 326                 return ERR_CAST(obj);
 327
 328         npages = PAGE_ALIGN(attach->dmabuf->size) / PAGE_SIZE;
 329
 330         obj->table = sg;
 331         obj->pages = kvmalloc_array(npages, sizeof(struct page *), GFP_KERNEL);
 332         if (!obj->pages) {
 333                 __vgem_gem_destroy(obj);
 334                 return ERR_PTR(-ENOMEM);
 335         }
 336         drm_prime_sg_to_page_addr_arrays(obj->table, obj->pages, NULL,
 337                                         npages);
 338         return &obj->base;
 339 }
 340
 341 static void *vgem_prime_vmap(struct drm_gem_object *obj)
 342 {
 343         long n_pages = obj->size >> PAGE_SHIFT;
 344         struct page **pages;
 345         void *addr;
 346
 347         pages = drm_gem_get_pages(obj);
 348         if (IS_ERR(pages))
 349                 return NULL;
 350
 351         addr = vmap(pages, n_pages, 0, pgprot_writecombine(PAGE_KERNEL));
 352         drm_gem_put_pages(obj, pages, false, false);
 353
 354         return addr;
 355 }
 356
 357 static void vgem_prime_vunmap(struct drm_gem_object *obj, void *vaddr)
 358 {
 359         vunmap(vaddr);
 360 }
 361
 362 static int vgem_prime_mmap(struct drm_gem_object *obj,
 363                            struct vm_area_struct *vma)
 364 {
 365         int ret;
 366
 367         if (obj->size < vma->vm_end - vma->vm_start)
 368                 return -EINVAL;
 369
 370         if (!obj->filp)
 371                 return -ENODEV;
 372
 373         ret = call_mmap(obj->filp, vma);
 374         if (ret)
 375                 return ret;
 376
 377         fput(vma->vm_file);
 378         vma->vm_file = get_file(obj->filp);
 379         vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
 380         vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags));
 381
 382         return 0;
 383 }
 384
 385 static void vgem_release(struct drm_device *dev)
 386 {
 387         struct vgem_device *vgem = container_of(dev, typeof(*vgem), drm);
 388
 389         platform_device_unregister(vgem->platform);
 390         drm_dev_fini(&vgem->drm);
 391
 392         kfree(vgem);
 393 }
 394
 395 static struct drm_driver vgem_driver = {
 396         .driver_features                = DRIVER_GEM | DRIVER_PRIME,
 397         .release                        = vgem_release,
 398         .open                           = vgem_open,
 399         .postclose                      = vgem_postclose,
 400         .gem_free_object_unlocked       = vgem_gem_free_object,
 401         .gem_vm_ops                     = &vgem_gem_vm_ops,
 402         .ioctls                         = vgem_ioctls,
 403         .num_ioctls                     = ARRAY_SIZE(vgem_ioctls),
 404         .fops                           = &vgem_driver_fops,
 405
 406         .dumb_create                    = vgem_gem_dumb_create,
 407         .dumb_map_offset                = vgem_gem_dumb_map,
 408
 409         .prime_handle_to_fd = drm_gem_prime_handle_to_fd,
 410         .prime_fd_to_handle = drm_gem_prime_fd_to_handle,
 411         .gem_prime_pin = vgem_prime_pin,
 412         .gem_prime_import = vgem_prime_import,
 413         .gem_prime_export = drm_gem_prime_export,
 414         .gem_prime_import_sg_table = vgem_prime_import_sg_table,
 415         .gem_prime_get_sg_table = vgem_prime_get_sg_table,
 416         .gem_prime_vmap = vgem_prime_vmap,
 417         .gem_prime_vunmap = vgem_prime_vunmap,
 418         .gem_prime_mmap = vgem_prime_mmap,
 419
 420         .name   = DRIVER_NAME,
 421         .desc   = DRIVER_DESC,
 422         .date   = DRIVER_DATE,
 423         .major  = DRIVER_MAJOR,
 424         .minor  = DRIVER_MINOR,
 425 };
 426
 427 static int __init vgem_init(void)
 428 {
 429         int ret;
 430
 431         vgem_device = kzalloc(sizeof(*vgem_device), GFP_KERNEL);
 432         if (!vgem_device)
 433                 return -ENOMEM;
 434
 435         ret = drm_dev_init(&vgem_device->drm, &vgem_driver, NULL);
 436         if (ret)
 437                 goto out_free;
 438
 439         vgem_device->platform =
 440                 platform_device_register_simple("vgem", -1, NULL, 0);
 441         if (IS_ERR(vgem_device->platform)) {
 442                 ret = PTR_ERR(vgem_device->platform);
 443                 goto out_fini;
 444         }
 445
 446         dma_coerce_mask_and_coherent(&vgem_device->platform->dev,
 447                                      DMA_BIT_MASK(64));
 448
 449         /* Final step: expose the device/driver to userspace */
 450         ret  = drm_dev_register(&vgem_device->drm, 0);
 451         if (ret)
 452                 goto out_unregister;
 453
 454         return 0;
 455
 456 out_unregister:
 457         platform_device_unregister(vgem_device->platform);
 458 out_fini:
 459         drm_dev_fini(&vgem_device->drm);
 460 out_free:
 461         kfree(vgem_device);
 462         return ret;
 463 }
 464
 465 static void __exit vgem_exit(void)
 466 {
 467         drm_dev_unregister(&vgem_device->drm);
 468         drm_dev_unref(&vgem_device->drm);
 469 }
 470
 471 module_init(vgem_init);
 472 module_exit(vgem_exit);
 473
 474 MODULE_AUTHOR("Red Hat, Inc.");
 475 MODULE_AUTHOR("Intel Corporation");
 476 MODULE_DESCRIPTION(DRIVER_DESC);
 477 MODULE_LICENSE("GPL and additional rights");