Hi Am 25.02.21 um 11:23 schrieb Daniel Vetter: > Aside from deleting lots of code the real motivation here is to switch > the mmap over to VM_PFNMAP, to be more consistent with what real gpu > drivers do. They're all VM_PFNMP, which means get_user_pages doesn't > work, and even if you try and there's a struct page behind that, > touching it and mucking around with its refcount can upset drivers > real bad. > > v2: Review from Thomas: > - sort #include > - drop more dead code that I didn't spot somehow > > v3: select DRM_GEM_SHMEM_HELPER to make it build (intel-gfx-ci) Since you're working on it, could you move the config item into a Kconfig file under vgem? Best regards Thomas > > Cc: Thomas Zimmermann > Acked-by: Thomas Zimmermann > Cc: John Stultz > Cc: Sumit Semwal > Cc: "Christian König" > Signed-off-by: Daniel Vetter > Cc: Melissa Wen > Cc: Chris Wilson > --- > drivers/gpu/drm/Kconfig | 1 + > drivers/gpu/drm/vgem/vgem_drv.c | 340 +------------------------------- > 2 files changed, 4 insertions(+), 337 deletions(-) > > diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig > index 8e73311de583..94e4ac830283 100644 > --- a/drivers/gpu/drm/Kconfig > +++ b/drivers/gpu/drm/Kconfig > @@ -274,6 +274,7 @@ source "drivers/gpu/drm/kmb/Kconfig" > config DRM_VGEM > tristate "Virtual GEM provider" > depends on DRM > + select DRM_GEM_SHMEM_HELPER > help > Choose this option to get a virtual graphics memory manager, > as used by Mesa's software renderer for enhanced performance. > diff --git a/drivers/gpu/drm/vgem/vgem_drv.c b/drivers/gpu/drm/vgem/vgem_drv.c > index a0e75f1d5d01..b1b3a5ffc542 100644 > --- a/drivers/gpu/drm/vgem/vgem_drv.c > +++ b/drivers/gpu/drm/vgem/vgem_drv.c > @@ -38,6 +38,7 @@ > > #include > #include > +#include > #include > #include > #include > @@ -50,87 +51,11 @@ > #define DRIVER_MAJOR 1 > #define DRIVER_MINOR 0 > > -static const struct drm_gem_object_funcs vgem_gem_object_funcs; > - > static struct vgem_device { > struct drm_device drm; > struct platform_device *platform; > } *vgem_device; > > -static void vgem_gem_free_object(struct drm_gem_object *obj) > -{ > - struct drm_vgem_gem_object *vgem_obj = to_vgem_bo(obj); > - > - kvfree(vgem_obj->pages); > - mutex_destroy(&vgem_obj->pages_lock); > - > - if (obj->import_attach) > - drm_prime_gem_destroy(obj, vgem_obj->table); > - > - drm_gem_object_release(obj); > - kfree(vgem_obj); > -} > - > -static vm_fault_t vgem_gem_fault(struct vm_fault *vmf) > -{ > - struct vm_area_struct *vma = vmf->vma; > - struct drm_vgem_gem_object *obj = vma->vm_private_data; > - /* We don't use vmf->pgoff since that has the fake offset */ > - unsigned long vaddr = vmf->address; > - vm_fault_t ret = VM_FAULT_SIGBUS; > - loff_t num_pages; > - pgoff_t page_offset; > - page_offset = (vaddr - vma->vm_start) >> PAGE_SHIFT; > - > - num_pages = DIV_ROUND_UP(obj->base.size, PAGE_SIZE); > - > - if (page_offset >= num_pages) > - return VM_FAULT_SIGBUS; > - > - mutex_lock(&obj->pages_lock); > - if (obj->pages) { > - get_page(obj->pages[page_offset]); > - vmf->page = obj->pages[page_offset]; > - ret = 0; > - } > - mutex_unlock(&obj->pages_lock); > - if (ret) { > - struct page *page; > - > - page = shmem_read_mapping_page( > - file_inode(obj->base.filp)->i_mapping, > - page_offset); > - if (!IS_ERR(page)) { > - vmf->page = page; > - ret = 0; > - } else switch (PTR_ERR(page)) { > - case -ENOSPC: > - case -ENOMEM: > - ret = VM_FAULT_OOM; > - break; > - case -EBUSY: > - ret = VM_FAULT_RETRY; > - break; > - case -EFAULT: > - case -EINVAL: > - ret = VM_FAULT_SIGBUS; > - break; > - default: > - WARN_ON(PTR_ERR(page)); > - ret = VM_FAULT_SIGBUS; > - break; > - } > - > - } > - return ret; > -} > - > -static const struct vm_operations_struct vgem_gem_vm_ops = { > - .fault = vgem_gem_fault, > - .open = drm_gem_vm_open, > - .close = drm_gem_vm_close, > -}; > - > static int vgem_open(struct drm_device *dev, struct drm_file *file) > { > struct vgem_file *vfile; > @@ -159,265 +84,12 @@ static void vgem_postclose(struct drm_device *dev, struct drm_file *file) > kfree(vfile); > } > > -static struct drm_vgem_gem_object *__vgem_gem_create(struct drm_device *dev, > - unsigned long size) > -{ > - struct drm_vgem_gem_object *obj; > - int ret; > - > - obj = kzalloc(sizeof(*obj), GFP_KERNEL); > - if (!obj) > - return ERR_PTR(-ENOMEM); > - > - obj->base.funcs = &vgem_gem_object_funcs; > - > - ret = drm_gem_object_init(dev, &obj->base, roundup(size, PAGE_SIZE)); > - if (ret) { > - kfree(obj); > - return ERR_PTR(ret); > - } > - > - mutex_init(&obj->pages_lock); > - > - return obj; > -} > - > -static void __vgem_gem_destroy(struct drm_vgem_gem_object *obj) > -{ > - drm_gem_object_release(&obj->base); > - kfree(obj); > -} > - > -static struct drm_gem_object *vgem_gem_create(struct drm_device *dev, > - struct drm_file *file, > - unsigned int *handle, > - unsigned long size) > -{ > - struct drm_vgem_gem_object *obj; > - int ret; > - > - obj = __vgem_gem_create(dev, size); > - if (IS_ERR(obj)) > - return ERR_CAST(obj); > - > - ret = drm_gem_handle_create(file, &obj->base, handle); > - if (ret) { > - drm_gem_object_put(&obj->base); > - return ERR_PTR(ret); > - } > - > - return &obj->base; > -} > - > -static int vgem_gem_dumb_create(struct drm_file *file, struct drm_device *dev, > - struct drm_mode_create_dumb *args) > -{ > - struct drm_gem_object *gem_object; > - u64 pitch, size; > - > - pitch = args->width * DIV_ROUND_UP(args->bpp, 8); > - size = args->height * pitch; > - if (size == 0) > - return -EINVAL; > - > - gem_object = vgem_gem_create(dev, file, &args->handle, size); > - if (IS_ERR(gem_object)) > - return PTR_ERR(gem_object); > - > - args->size = gem_object->size; > - args->pitch = pitch; > - > - drm_gem_object_put(gem_object); > - > - DRM_DEBUG("Created object of size %llu\n", args->size); > - > - return 0; > -} > - > static struct drm_ioctl_desc vgem_ioctls[] = { > DRM_IOCTL_DEF_DRV(VGEM_FENCE_ATTACH, vgem_fence_attach_ioctl, DRM_RENDER_ALLOW), > DRM_IOCTL_DEF_DRV(VGEM_FENCE_SIGNAL, vgem_fence_signal_ioctl, DRM_RENDER_ALLOW), > }; > > -static int vgem_mmap(struct file *filp, struct vm_area_struct *vma) > -{ > - unsigned long flags = vma->vm_flags; > - int ret; > - > - ret = drm_gem_mmap(filp, vma); > - if (ret) > - return ret; > - > - /* Keep the WC mmaping set by drm_gem_mmap() but our pages > - * are ordinary and not special. > - */ > - vma->vm_flags = flags | VM_DONTEXPAND | VM_DONTDUMP; > - return 0; > -} > - > -static const struct file_operations vgem_driver_fops = { > - .owner = THIS_MODULE, > - .open = drm_open, > - .mmap = vgem_mmap, > - .poll = drm_poll, > - .read = drm_read, > - .unlocked_ioctl = drm_ioctl, > - .compat_ioctl = drm_compat_ioctl, > - .release = drm_release, > -}; > - > -static struct page **vgem_pin_pages(struct drm_vgem_gem_object *bo) > -{ > - mutex_lock(&bo->pages_lock); > - if (bo->pages_pin_count++ == 0) { > - struct page **pages; > - > - pages = drm_gem_get_pages(&bo->base); > - if (IS_ERR(pages)) { > - bo->pages_pin_count--; > - mutex_unlock(&bo->pages_lock); > - return pages; > - } > - > - bo->pages = pages; > - } > - mutex_unlock(&bo->pages_lock); > - > - return bo->pages; > -} > - > -static void vgem_unpin_pages(struct drm_vgem_gem_object *bo) > -{ > - mutex_lock(&bo->pages_lock); > - if (--bo->pages_pin_count == 0) { > - drm_gem_put_pages(&bo->base, bo->pages, true, true); > - bo->pages = NULL; > - } > - mutex_unlock(&bo->pages_lock); > -} > - > -static int vgem_prime_pin(struct drm_gem_object *obj) > -{ > - struct drm_vgem_gem_object *bo = to_vgem_bo(obj); > - long n_pages = obj->size >> PAGE_SHIFT; > - struct page **pages; > - > - pages = vgem_pin_pages(bo); > - if (IS_ERR(pages)) > - return PTR_ERR(pages); > - > - /* Flush the object from the CPU cache so that importers can rely > - * on coherent indirect access via the exported dma-address. > - */ > - drm_clflush_pages(pages, n_pages); > - > - return 0; > -} > - > -static void vgem_prime_unpin(struct drm_gem_object *obj) > -{ > - struct drm_vgem_gem_object *bo = to_vgem_bo(obj); > - > - vgem_unpin_pages(bo); > -} > - > -static struct sg_table *vgem_prime_get_sg_table(struct drm_gem_object *obj) > -{ > - struct drm_vgem_gem_object *bo = to_vgem_bo(obj); > - > - return drm_prime_pages_to_sg(obj->dev, bo->pages, bo->base.size >> PAGE_SHIFT); > -} > - > -static struct drm_gem_object* vgem_prime_import(struct drm_device *dev, > - struct dma_buf *dma_buf) > -{ > - struct vgem_device *vgem = container_of(dev, typeof(*vgem), drm); > - > - return drm_gem_prime_import_dev(dev, dma_buf, &vgem->platform->dev); > -} > - > -static struct drm_gem_object *vgem_prime_import_sg_table(struct drm_device *dev, > - struct dma_buf_attachment *attach, struct sg_table *sg) > -{ > - struct drm_vgem_gem_object *obj; > - int npages; > - > - obj = __vgem_gem_create(dev, attach->dmabuf->size); > - if (IS_ERR(obj)) > - return ERR_CAST(obj); > - > - npages = PAGE_ALIGN(attach->dmabuf->size) / PAGE_SIZE; > - > - obj->table = sg; > - obj->pages = kvmalloc_array(npages, sizeof(struct page *), GFP_KERNEL); > - if (!obj->pages) { > - __vgem_gem_destroy(obj); > - return ERR_PTR(-ENOMEM); > - } > - > - obj->pages_pin_count++; /* perma-pinned */ > - drm_prime_sg_to_page_array(obj->table, obj->pages, npages); > - return &obj->base; > -} > - > -static int vgem_prime_vmap(struct drm_gem_object *obj, struct dma_buf_map *map) > -{ > - struct drm_vgem_gem_object *bo = to_vgem_bo(obj); > - long n_pages = obj->size >> PAGE_SHIFT; > - struct page **pages; > - void *vaddr; > - > - pages = vgem_pin_pages(bo); > - if (IS_ERR(pages)) > - return PTR_ERR(pages); > - > - vaddr = vmap(pages, n_pages, 0, pgprot_writecombine(PAGE_KERNEL)); > - if (!vaddr) > - return -ENOMEM; > - dma_buf_map_set_vaddr(map, vaddr); > - > - return 0; > -} > - > -static void vgem_prime_vunmap(struct drm_gem_object *obj, struct dma_buf_map *map) > -{ > - struct drm_vgem_gem_object *bo = to_vgem_bo(obj); > - > - vunmap(map->vaddr); > - vgem_unpin_pages(bo); > -} > - > -static int vgem_prime_mmap(struct drm_gem_object *obj, > - struct vm_area_struct *vma) > -{ > - int ret; > - > - if (obj->size < vma->vm_end - vma->vm_start) > - return -EINVAL; > - > - if (!obj->filp) > - return -ENODEV; > - > - ret = call_mmap(obj->filp, vma); > - if (ret) > - return ret; > - > - vma_set_file(vma, obj->filp); > - vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP; > - vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags)); > - > - return 0; > -} > - > -static const struct drm_gem_object_funcs vgem_gem_object_funcs = { > - .free = vgem_gem_free_object, > - .pin = vgem_prime_pin, > - .unpin = vgem_prime_unpin, > - .get_sg_table = vgem_prime_get_sg_table, > - .vmap = vgem_prime_vmap, > - .vunmap = vgem_prime_vunmap, > - .vm_ops = &vgem_gem_vm_ops, > -}; > +DEFINE_DRM_GEM_FOPS(vgem_driver_fops); > > static const struct drm_driver vgem_driver = { > .driver_features = DRIVER_GEM | DRIVER_RENDER, > @@ -427,13 +99,7 @@ static const struct drm_driver vgem_driver = { > .num_ioctls = ARRAY_SIZE(vgem_ioctls), > .fops = &vgem_driver_fops, > > - .dumb_create = vgem_gem_dumb_create, > - > - .prime_handle_to_fd = drm_gem_prime_handle_to_fd, > - .prime_fd_to_handle = drm_gem_prime_fd_to_handle, > - .gem_prime_import = vgem_prime_import, > - .gem_prime_import_sg_table = vgem_prime_import_sg_table, > - .gem_prime_mmap = vgem_prime_mmap, > + DRM_GEM_SHMEM_DRIVER_OPS, > > .name = DRIVER_NAME, > .desc = DRIVER_DESC, > -- Thomas Zimmermann Graphics Driver Developer SUSE Software Solutions Germany GmbH Maxfeldstr. 5, 90409 Nürnberg, Germany (HRB 36809, AG Nürnberg) Geschäftsführer: Felix Imendörffer