2 * Copyright 2011 Red Hat, Inc.
3 * Copyright © 2014 The Chromium OS Authors
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:
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
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.
24 * Adam Jackson <ajax@redhat.com>
25 * Ben Widawsky <ben@bwidawsk.net>
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.
33 #include <linux/dma-buf.h>
34 #include <linux/module.h>
35 #include <linux/platform_device.h>
36 #include <linux/shmem_fs.h>
37 #include <linux/vmalloc.h>
39 #include <drm/drm_drv.h>
40 #include <drm/drm_file.h>
41 #include <drm/drm_ioctl.h>
42 #include <drm/drm_prime.h>
46 #define DRIVER_NAME "vgem"
47 #define DRIVER_DESC "Virtual GEM provider"
48 #define DRIVER_DATE "20120112"
49 #define DRIVER_MAJOR 1
50 #define DRIVER_MINOR 0
52 static struct vgem_device {
53 struct drm_device drm;
54 struct platform_device *platform;
57 static void vgem_gem_free_object(struct drm_gem_object *obj)
59 struct drm_vgem_gem_object *vgem_obj = to_vgem_bo(obj);
61 kvfree(vgem_obj->pages);
62 mutex_destroy(&vgem_obj->pages_lock);
64 if (obj->import_attach)
65 drm_prime_gem_destroy(obj, vgem_obj->table);
67 drm_gem_object_release(obj);
71 static vm_fault_t vgem_gem_fault(struct vm_fault *vmf)
73 struct vm_area_struct *vma = vmf->vma;
74 struct drm_vgem_gem_object *obj = vma->vm_private_data;
75 /* We don't use vmf->pgoff since that has the fake offset */
76 unsigned long vaddr = vmf->address;
77 vm_fault_t ret = VM_FAULT_SIGBUS;
80 page_offset = (vaddr - vma->vm_start) >> PAGE_SHIFT;
82 num_pages = DIV_ROUND_UP(obj->base.size, PAGE_SIZE);
84 if (page_offset >= num_pages)
85 return VM_FAULT_SIGBUS;
87 mutex_lock(&obj->pages_lock);
89 get_page(obj->pages[page_offset]);
90 vmf->page = obj->pages[page_offset];
93 mutex_unlock(&obj->pages_lock);
97 page = shmem_read_mapping_page(
98 file_inode(obj->base.filp)->i_mapping,
103 } else switch (PTR_ERR(page)) {
109 ret = VM_FAULT_RETRY;
113 ret = VM_FAULT_SIGBUS;
116 WARN_ON(PTR_ERR(page));
117 ret = VM_FAULT_SIGBUS;
125 static const struct vm_operations_struct vgem_gem_vm_ops = {
126 .fault = vgem_gem_fault,
127 .open = drm_gem_vm_open,
128 .close = drm_gem_vm_close,
131 static int vgem_open(struct drm_device *dev, struct drm_file *file)
133 struct vgem_file *vfile;
136 vfile = kzalloc(sizeof(*vfile), GFP_KERNEL);
140 file->driver_priv = vfile;
142 ret = vgem_fence_open(vfile);
151 static void vgem_postclose(struct drm_device *dev, struct drm_file *file)
153 struct vgem_file *vfile = file->driver_priv;
155 vgem_fence_close(vfile);
159 static struct drm_vgem_gem_object *__vgem_gem_create(struct drm_device *dev,
162 struct drm_vgem_gem_object *obj;
165 obj = kzalloc(sizeof(*obj), GFP_KERNEL);
167 return ERR_PTR(-ENOMEM);
169 ret = drm_gem_object_init(dev, &obj->base, roundup(size, PAGE_SIZE));
175 mutex_init(&obj->pages_lock);
180 static void __vgem_gem_destroy(struct drm_vgem_gem_object *obj)
182 drm_gem_object_release(&obj->base);
186 static struct drm_gem_object *vgem_gem_create(struct drm_device *dev,
187 struct drm_file *file,
188 unsigned int *handle,
191 struct drm_vgem_gem_object *obj;
194 obj = __vgem_gem_create(dev, size);
196 return ERR_CAST(obj);
198 ret = drm_gem_handle_create(file, &obj->base, handle);
200 drm_gem_object_put_unlocked(&obj->base);
207 static int vgem_gem_dumb_create(struct drm_file *file, struct drm_device *dev,
208 struct drm_mode_create_dumb *args)
210 struct drm_gem_object *gem_object;
213 pitch = args->width * DIV_ROUND_UP(args->bpp, 8);
214 size = args->height * pitch;
218 gem_object = vgem_gem_create(dev, file, &args->handle, size);
219 if (IS_ERR(gem_object))
220 return PTR_ERR(gem_object);
222 args->size = gem_object->size;
225 drm_gem_object_put_unlocked(gem_object);
227 DRM_DEBUG("Created object of size %llu\n", args->size);
232 static int vgem_gem_dumb_map(struct drm_file *file, struct drm_device *dev,
233 uint32_t handle, uint64_t *offset)
235 struct drm_gem_object *obj;
238 obj = drm_gem_object_lookup(file, handle);
247 ret = drm_gem_create_mmap_offset(obj);
251 *offset = drm_vma_node_offset_addr(&obj->vma_node);
253 drm_gem_object_put_unlocked(obj);
258 static struct drm_ioctl_desc vgem_ioctls[] = {
259 DRM_IOCTL_DEF_DRV(VGEM_FENCE_ATTACH, vgem_fence_attach_ioctl, DRM_RENDER_ALLOW),
260 DRM_IOCTL_DEF_DRV(VGEM_FENCE_SIGNAL, vgem_fence_signal_ioctl, DRM_RENDER_ALLOW),
263 static int vgem_mmap(struct file *filp, struct vm_area_struct *vma)
265 unsigned long flags = vma->vm_flags;
268 ret = drm_gem_mmap(filp, vma);
272 /* Keep the WC mmaping set by drm_gem_mmap() but our pages
273 * are ordinary and not special.
275 vma->vm_flags = flags | VM_DONTEXPAND | VM_DONTDUMP;
279 static const struct file_operations vgem_driver_fops = {
280 .owner = THIS_MODULE,
285 .unlocked_ioctl = drm_ioctl,
286 .compat_ioctl = drm_compat_ioctl,
287 .release = drm_release,
290 static struct page **vgem_pin_pages(struct drm_vgem_gem_object *bo)
292 mutex_lock(&bo->pages_lock);
293 if (bo->pages_pin_count++ == 0) {
296 pages = drm_gem_get_pages(&bo->base);
298 bo->pages_pin_count--;
299 mutex_unlock(&bo->pages_lock);
305 mutex_unlock(&bo->pages_lock);
310 static void vgem_unpin_pages(struct drm_vgem_gem_object *bo)
312 mutex_lock(&bo->pages_lock);
313 if (--bo->pages_pin_count == 0) {
314 drm_gem_put_pages(&bo->base, bo->pages, true, true);
317 mutex_unlock(&bo->pages_lock);
320 static int vgem_prime_pin(struct drm_gem_object *obj)
322 struct drm_vgem_gem_object *bo = to_vgem_bo(obj);
323 long n_pages = obj->size >> PAGE_SHIFT;
326 pages = vgem_pin_pages(bo);
328 return PTR_ERR(pages);
330 /* Flush the object from the CPU cache so that importers can rely
331 * on coherent indirect access via the exported dma-address.
333 drm_clflush_pages(pages, n_pages);
338 static void vgem_prime_unpin(struct drm_gem_object *obj)
340 struct drm_vgem_gem_object *bo = to_vgem_bo(obj);
342 vgem_unpin_pages(bo);
345 static struct sg_table *vgem_prime_get_sg_table(struct drm_gem_object *obj)
347 struct drm_vgem_gem_object *bo = to_vgem_bo(obj);
349 return drm_prime_pages_to_sg(bo->pages, bo->base.size >> PAGE_SHIFT);
352 static struct drm_gem_object* vgem_prime_import(struct drm_device *dev,
353 struct dma_buf *dma_buf)
355 struct vgem_device *vgem = container_of(dev, typeof(*vgem), drm);
357 return drm_gem_prime_import_dev(dev, dma_buf, &vgem->platform->dev);
360 static struct drm_gem_object *vgem_prime_import_sg_table(struct drm_device *dev,
361 struct dma_buf_attachment *attach, struct sg_table *sg)
363 struct drm_vgem_gem_object *obj;
366 obj = __vgem_gem_create(dev, attach->dmabuf->size);
368 return ERR_CAST(obj);
370 npages = PAGE_ALIGN(attach->dmabuf->size) / PAGE_SIZE;
373 obj->pages = kvmalloc_array(npages, sizeof(struct page *), GFP_KERNEL);
375 __vgem_gem_destroy(obj);
376 return ERR_PTR(-ENOMEM);
379 obj->pages_pin_count++; /* perma-pinned */
380 drm_prime_sg_to_page_addr_arrays(obj->table, obj->pages, NULL,
385 static void *vgem_prime_vmap(struct drm_gem_object *obj)
387 struct drm_vgem_gem_object *bo = to_vgem_bo(obj);
388 long n_pages = obj->size >> PAGE_SHIFT;
391 pages = vgem_pin_pages(bo);
395 return vmap(pages, n_pages, 0, pgprot_writecombine(PAGE_KERNEL));
398 static void vgem_prime_vunmap(struct drm_gem_object *obj, void *vaddr)
400 struct drm_vgem_gem_object *bo = to_vgem_bo(obj);
403 vgem_unpin_pages(bo);
406 static int vgem_prime_mmap(struct drm_gem_object *obj,
407 struct vm_area_struct *vma)
411 if (obj->size < vma->vm_end - vma->vm_start)
417 ret = call_mmap(obj->filp, vma);
422 vma->vm_file = get_file(obj->filp);
423 vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
424 vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags));
429 static void vgem_release(struct drm_device *dev)
431 struct vgem_device *vgem = container_of(dev, typeof(*vgem), drm);
433 platform_device_unregister(vgem->platform);
434 drm_dev_fini(&vgem->drm);
439 static struct drm_driver vgem_driver = {
440 .driver_features = DRIVER_GEM | DRIVER_RENDER,
441 .release = vgem_release,
443 .postclose = vgem_postclose,
444 .gem_free_object_unlocked = vgem_gem_free_object,
445 .gem_vm_ops = &vgem_gem_vm_ops,
446 .ioctls = vgem_ioctls,
447 .num_ioctls = ARRAY_SIZE(vgem_ioctls),
448 .fops = &vgem_driver_fops,
450 .dumb_create = vgem_gem_dumb_create,
451 .dumb_map_offset = vgem_gem_dumb_map,
453 .prime_handle_to_fd = drm_gem_prime_handle_to_fd,
454 .prime_fd_to_handle = drm_gem_prime_fd_to_handle,
455 .gem_prime_pin = vgem_prime_pin,
456 .gem_prime_unpin = vgem_prime_unpin,
457 .gem_prime_import = vgem_prime_import,
458 .gem_prime_import_sg_table = vgem_prime_import_sg_table,
459 .gem_prime_get_sg_table = vgem_prime_get_sg_table,
460 .gem_prime_vmap = vgem_prime_vmap,
461 .gem_prime_vunmap = vgem_prime_vunmap,
462 .gem_prime_mmap = vgem_prime_mmap,
467 .major = DRIVER_MAJOR,
468 .minor = DRIVER_MINOR,
471 static int __init vgem_init(void)
475 vgem_device = kzalloc(sizeof(*vgem_device), GFP_KERNEL);
479 vgem_device->platform =
480 platform_device_register_simple("vgem", -1, NULL, 0);
481 if (IS_ERR(vgem_device->platform)) {
482 ret = PTR_ERR(vgem_device->platform);
486 dma_coerce_mask_and_coherent(&vgem_device->platform->dev,
488 ret = drm_dev_init(&vgem_device->drm, &vgem_driver,
489 &vgem_device->platform->dev);
493 /* Final step: expose the device/driver to userspace */
494 ret = drm_dev_register(&vgem_device->drm, 0);
501 drm_dev_fini(&vgem_device->drm);
503 platform_device_unregister(vgem_device->platform);
509 static void __exit vgem_exit(void)
511 drm_dev_unregister(&vgem_device->drm);
512 drm_dev_put(&vgem_device->drm);
515 module_init(vgem_init);
516 module_exit(vgem_exit);
518 MODULE_AUTHOR("Red Hat, Inc.");
519 MODULE_AUTHOR("Intel Corporation");
520 MODULE_DESCRIPTION(DRIVER_DESC);
521 MODULE_LICENSE("GPL and additional rights");