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 platform_device *vgem_platform;
  46
  47 static void vgem_gem_free_object(struct drm_gem_object *obj)
  48 {
  49         struct drm_vgem_gem_object *vgem_obj = to_vgem_bo(obj);
  50
  51         drm_free_large(vgem_obj->pages);
  52
  53         if (obj->import_attach)
  54                 drm_prime_gem_destroy(obj, vgem_obj->table);
  55
  56         drm_gem_object_release(obj);
  57         kfree(vgem_obj);
  58 }
  59
  60 static int vgem_gem_fault(struct vm_fault *vmf)
  61 {
  62         struct vm_area_struct *vma = vmf->vma;
  63         struct drm_vgem_gem_object *obj = vma->vm_private_data;
  64         /* We don't use vmf->pgoff since that has the fake offset */
  65         unsigned long vaddr = vmf->address;
  66         int ret;
  67         loff_t num_pages;
  68         pgoff_t page_offset;
  69         page_offset = (vaddr - vma->vm_start) >> PAGE_SHIFT;
  70
  71         num_pages = DIV_ROUND_UP(obj->base.size, PAGE_SIZE);
  72
  73         if (page_offset > num_pages)
  74                 return VM_FAULT_SIGBUS;
  75
  76         if (obj->pages) {
  77                 get_page(obj->pages[page_offset]);
  78                 vmf->page = obj->pages[page_offset];
  79                 ret = 0;
  80         } else {
  81                 struct page *page;
  82
  83                 page = shmem_read_mapping_page(
  84                                         file_inode(obj->base.filp)->i_mapping,
  85                                         page_offset);
  86                 if (!IS_ERR(page)) {
  87                         vmf->page = page;
  88                         ret = 0;
  89                 } else switch (PTR_ERR(page)) {
  90                         case -ENOSPC:
  91                         case -ENOMEM:
  92                                 ret = VM_FAULT_OOM;
  93                                 break;
  94                         case -EBUSY:
  95                                 ret = VM_FAULT_RETRY;
  96                                 break;
  97                         case -EFAULT:
  98                         case -EINVAL:
  99                                 ret = VM_FAULT_SIGBUS;
 100                                 break;
 101                         default:
 102                                 WARN_ON(PTR_ERR(page));
 103                                 ret = VM_FAULT_SIGBUS;
 104                                 break;
 105                 }
 106
 107         }
 108         return ret;
 109 }
 110
 111 static const struct vm_operations_struct vgem_gem_vm_ops = {
 112         .fault = vgem_gem_fault,
 113         .open = drm_gem_vm_open,
 114         .close = drm_gem_vm_close,
 115 };
 116
 117 static int vgem_open(struct drm_device *dev, struct drm_file *file)
 118 {
 119         struct vgem_file *vfile;
 120         int ret;
 121
 122         vfile = kzalloc(sizeof(*vfile), GFP_KERNEL);
 123         if (!vfile)
 124                 return -ENOMEM;
 125
 126         file->driver_priv = vfile;
 127
 128         ret = vgem_fence_open(vfile);
 129         if (ret) {
 130                 kfree(vfile);
 131                 return ret;
 132         }
 133
 134         return 0;
 135 }
 136
 137 static void vgem_postclose(struct drm_device *dev, struct drm_file *file)
 138 {
 139         struct vgem_file *vfile = file->driver_priv;
 140
 141         vgem_fence_close(vfile);
 142         kfree(vfile);
 143 }
 144
 145 static struct drm_vgem_gem_object *__vgem_gem_create(struct drm_device *dev,
 146                                                 unsigned long size)
 147 {
 148         struct drm_vgem_gem_object *obj;
 149         int ret;
 150
 151         obj = kzalloc(sizeof(*obj), GFP_KERNEL);
 152         if (!obj)
 153                 return ERR_PTR(-ENOMEM);
 154
 155         ret = drm_gem_object_init(dev, &obj->base, roundup(size, PAGE_SIZE));
 156         if (ret) {
 157                 kfree(obj);
 158                 return ERR_PTR(ret);
 159         }
 160
 161         return obj;
 162 }
 163
 164 static void __vgem_gem_destroy(struct drm_vgem_gem_object *obj)
 165 {
 166         drm_gem_object_release(&obj->base);
 167         kfree(obj);
 168 }
 169
 170 static struct drm_gem_object *vgem_gem_create(struct drm_device *dev,
 171                                               struct drm_file *file,
 172                                               unsigned int *handle,
 173                                               unsigned long size)
 174 {
 175         struct drm_vgem_gem_object *obj;
 176         int ret;
 177
 178         obj = __vgem_gem_create(dev, size);
 179         if (IS_ERR(obj))
 180                 return ERR_CAST(obj);
 181
 182         ret = drm_gem_handle_create(file, &obj->base, handle);
 183         drm_gem_object_unreference_unlocked(&obj->base);
 184         if (ret)
 185                 goto err;
 186
 187         return &obj->base;
 188
 189 err:
 190         __vgem_gem_destroy(obj);
 191         return ERR_PTR(ret);
 192 }
 193
 194 static int vgem_gem_dumb_create(struct drm_file *file, struct drm_device *dev,
 195                                 struct drm_mode_create_dumb *args)
 196 {
 197         struct drm_gem_object *gem_object;
 198         u64 pitch, size;
 199
 200         pitch = args->width * DIV_ROUND_UP(args->bpp, 8);
 201         size = args->height * pitch;
 202         if (size == 0)
 203                 return -EINVAL;
 204
 205         gem_object = vgem_gem_create(dev, file, &args->handle, size);
 206         if (IS_ERR(gem_object))
 207                 return PTR_ERR(gem_object);
 208
 209         args->size = gem_object->size;
 210         args->pitch = pitch;
 211
 212         DRM_DEBUG_DRIVER("Created object of size %lld\n", size);
 213
 214         return 0;
 215 }
 216
 217 static int vgem_gem_dumb_map(struct drm_file *file, struct drm_device *dev,
 218                              uint32_t handle, uint64_t *offset)
 219 {
 220         struct drm_gem_object *obj;
 221         int ret;
 222
 223         obj = drm_gem_object_lookup(file, handle);
 224         if (!obj)
 225                 return -ENOENT;
 226
 227         if (!obj->filp) {
 228                 ret = -EINVAL;
 229                 goto unref;
 230         }
 231
 232         ret = drm_gem_create_mmap_offset(obj);
 233         if (ret)
 234                 goto unref;
 235
 236         *offset = drm_vma_node_offset_addr(&obj->vma_node);
 237 unref:
 238         drm_gem_object_unreference_unlocked(obj);
 239
 240         return ret;
 241 }
 242
 243 static struct drm_ioctl_desc vgem_ioctls[] = {
 244         DRM_IOCTL_DEF_DRV(VGEM_FENCE_ATTACH, vgem_fence_attach_ioctl, DRM_AUTH|DRM_RENDER_ALLOW),
 245         DRM_IOCTL_DEF_DRV(VGEM_FENCE_SIGNAL, vgem_fence_signal_ioctl, DRM_AUTH|DRM_RENDER_ALLOW),
 246 };
 247
 248 static int vgem_mmap(struct file *filp, struct vm_area_struct *vma)
 249 {
 250         unsigned long flags = vma->vm_flags;
 251         int ret;
 252
 253         ret = drm_gem_mmap(filp, vma);
 254         if (ret)
 255                 return ret;
 256
 257         /* Keep the WC mmaping set by drm_gem_mmap() but our pages
 258          * are ordinary and not special.
 259          */
 260         vma->vm_flags = flags | VM_DONTEXPAND | VM_DONTDUMP;
 261         return 0;
 262 }
 263
 264 static const struct file_operations vgem_driver_fops = {
 265         .owner          = THIS_MODULE,
 266         .open           = drm_open,
 267         .mmap           = vgem_mmap,
 268         .poll           = drm_poll,
 269         .read           = drm_read,
 270         .unlocked_ioctl = drm_ioctl,
 271         .release        = drm_release,
 272 };
 273
 274 static int vgem_prime_pin(struct drm_gem_object *obj)
 275 {
 276         long n_pages = obj->size >> PAGE_SHIFT;
 277         struct page **pages;
 278
 279         /* Flush the object from the CPU cache so that importers can rely
 280          * on coherent indirect access via the exported dma-address.
 281          */
 282         pages = drm_gem_get_pages(obj);
 283         if (IS_ERR(pages))
 284                 return PTR_ERR(pages);
 285
 286         drm_clflush_pages(pages, n_pages);
 287         drm_gem_put_pages(obj, pages, true, false);
 288
 289         return 0;
 290 }
 291
 292 static struct sg_table *vgem_prime_get_sg_table(struct drm_gem_object *obj)
 293 {
 294         struct sg_table *st;
 295         struct page **pages;
 296
 297         pages = drm_gem_get_pages(obj);
 298         if (IS_ERR(pages))
 299                 return ERR_CAST(pages);
 300
 301         st = drm_prime_pages_to_sg(pages, obj->size >> PAGE_SHIFT);
 302         drm_gem_put_pages(obj, pages, false, false);
 303
 304         return st;
 305 }
 306
 307 static struct drm_gem_object* vgem_prime_import(struct drm_device *dev,
 308                                                 struct dma_buf *dma_buf)
 309 {
 310         return drm_gem_prime_import_dev(dev, dma_buf, &vgem_platform->dev);
 311 }
 312
 313 static struct drm_gem_object *vgem_prime_import_sg_table(struct drm_device *dev,
 314                         struct dma_buf_attachment *attach, struct sg_table *sg)
 315 {
 316         struct drm_vgem_gem_object *obj;
 317         int npages;
 318
 319         obj = __vgem_gem_create(dev, attach->dmabuf->size);
 320         if (IS_ERR(obj))
 321                 return ERR_CAST(obj);
 322
 323         npages = PAGE_ALIGN(attach->dmabuf->size) / PAGE_SIZE;
 324
 325         obj->table = sg;
 326         obj->pages = drm_malloc_ab(npages, sizeof(struct page *));
 327         if (!obj->pages) {
 328                 __vgem_gem_destroy(obj);
 329                 return ERR_PTR(-ENOMEM);
 330         }
 331         drm_prime_sg_to_page_addr_arrays(obj->table, obj->pages, NULL,
 332                                         npages);
 333         return &obj->base;
 334 }
 335
 336 static void *vgem_prime_vmap(struct drm_gem_object *obj)
 337 {
 338         long n_pages = obj->size >> PAGE_SHIFT;
 339         struct page **pages;
 340         void *addr;
 341
 342         pages = drm_gem_get_pages(obj);
 343         if (IS_ERR(pages))
 344                 return NULL;
 345
 346         addr = vmap(pages, n_pages, 0, pgprot_writecombine(PAGE_KERNEL));
 347         drm_gem_put_pages(obj, pages, false, false);
 348
 349         return addr;
 350 }
 351
 352 static void vgem_prime_vunmap(struct drm_gem_object *obj, void *vaddr)
 353 {
 354         vunmap(vaddr);
 355 }
 356
 357 static int vgem_prime_mmap(struct drm_gem_object *obj,
 358                            struct vm_area_struct *vma)
 359 {
 360         int ret;
 361
 362         if (obj->size < vma->vm_end - vma->vm_start)
 363                 return -EINVAL;
 364
 365         if (!obj->filp)
 366                 return -ENODEV;
 367
 368         ret = call_mmap(obj->filp, vma);
 369         if (ret)
 370                 return ret;
 371
 372         fput(vma->vm_file);
 373         vma->vm_file = get_file(obj->filp);
 374         vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
 375         vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags));
 376
 377         return 0;
 378 }
 379
 380 static struct drm_driver vgem_driver = {
 381         .driver_features                = DRIVER_GEM | DRIVER_PRIME,
 382         .open                           = vgem_open,
 383         .postclose                      = vgem_postclose,
 384         .gem_free_object_unlocked       = vgem_gem_free_object,
 385         .gem_vm_ops                     = &vgem_gem_vm_ops,
 386         .ioctls                         = vgem_ioctls,
 387         .num_ioctls                     = ARRAY_SIZE(vgem_ioctls),
 388         .fops                           = &vgem_driver_fops,
 389
 390         .dumb_create                    = vgem_gem_dumb_create,
 391         .dumb_map_offset                = vgem_gem_dumb_map,
 392
 393         .prime_handle_to_fd = drm_gem_prime_handle_to_fd,
 394         .prime_fd_to_handle = drm_gem_prime_fd_to_handle,
 395         .gem_prime_pin = vgem_prime_pin,
 396         .gem_prime_import = vgem_prime_import,
 397         .gem_prime_export = drm_gem_prime_export,
 398         .gem_prime_import_sg_table = vgem_prime_import_sg_table,
 399         .gem_prime_get_sg_table = vgem_prime_get_sg_table,
 400         .gem_prime_vmap = vgem_prime_vmap,
 401         .gem_prime_vunmap = vgem_prime_vunmap,
 402         .gem_prime_mmap = vgem_prime_mmap,
 403
 404         .name   = DRIVER_NAME,
 405         .desc   = DRIVER_DESC,
 406         .date   = DRIVER_DATE,
 407         .major  = DRIVER_MAJOR,
 408         .minor  = DRIVER_MINOR,
 409 };
 410
 411 static struct drm_device *vgem_device;
 412
 413 static int __init vgem_init(void)
 414 {
 415         int ret;
 416
 417         vgem_device = drm_dev_alloc(&vgem_driver, NULL);
 418         if (IS_ERR(vgem_device))
 419                 return PTR_ERR(vgem_device);
 420
 421         vgem_platform = platform_device_register_simple("vgem",
 422                                         -1, NULL, 0);
 423
 424         if (!vgem_platform) {
 425                 ret = -ENODEV;
 426                 goto out;
 427         }
 428
 429         dma_coerce_mask_and_coherent(&vgem_platform->dev,
 430                                         DMA_BIT_MASK(64));
 431
 432         ret  = drm_dev_register(vgem_device, 0);
 433         if (ret)
 434                 goto out_unref;
 435
 436         return 0;
 437
 438 out_unref:
 439         platform_device_unregister(vgem_platform);
 440 out:
 441         drm_dev_unref(vgem_device);
 442         return ret;
 443 }
 444
 445 static void __exit vgem_exit(void)
 446 {
 447         platform_device_unregister(vgem_platform);
 448         drm_dev_unregister(vgem_device);
 449         drm_dev_unref(vgem_device);
 450 }
 451
 452 module_init(vgem_init);
 453 module_exit(vgem_exit);
 454
 455 MODULE_AUTHOR("Red Hat, Inc.");
 456 MODULE_AUTHOR("Intel Corporation");
 457 MODULE_DESCRIPTION(DRIVER_DESC);
 458 MODULE_LICENSE("GPL and additional rights");