diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c index efc79bbf3c73..933fc89dd648 100644 --- a/drivers/gpu/drm/drm_gem.c +++ b/drivers/gpu/drm/drm_gem.c @@ -36,6 +36,7 @@ #include #include #include +#include #include #include #include @@ -1177,36 +1178,27 @@ int drm_gem_mmap_obj(struct drm_gem_object *obj, unsigned long obj_size, } EXPORT_SYMBOL(drm_gem_mmap_obj); -/** - * drm_gem_mmap - memory map routine for GEM objects - * @filp: DRM file pointer - * @vma: VMA for the area to be mapped - * - * If a driver supports GEM object mapping, mmap calls on the DRM file - * descriptor will end up here. - * - * Look up the GEM object based on the offset passed in (vma->vm_pgoff will - * contain the fake offset we created when the GTT map ioctl was called on - * the object) and map it with a call to drm_gem_mmap_obj(). - * - * If the caller is not granted access to the buffer object, the mmap will fail - * with EACCES. Please see the vma manager for more information. +/* + * Look up a GEM object in offset space based on the exact start address. The + * caller must be granted access to the object. Returns a GEM object on success + * or a negative error code on failure. The returned GEM object needs to be + * released with drm_gem_object_put(). */ -int drm_gem_mmap(struct file *filp, struct vm_area_struct *vma) +static struct drm_gem_object * +drm_gem_object_lookup_at_offset(struct file *filp, unsigned long start, + unsigned long pages) { struct drm_file *priv = filp->private_data; struct drm_device *dev = priv->minor->dev; struct drm_gem_object *obj = NULL; struct drm_vma_offset_node *node; - int ret; if (drm_dev_is_unplugged(dev)) - return -ENODEV; + return ERR_PTR(-ENODEV); drm_vma_offset_lock_lookup(dev->vma_offset_manager); node = drm_vma_offset_exact_lookup_locked(dev->vma_offset_manager, - vma->vm_pgoff, - vma_pages(vma)); + start, pages); if (likely(node)) { obj = container_of(node, struct drm_gem_object, vma_node); /* @@ -1225,14 +1217,86 @@ int drm_gem_mmap(struct file *filp, struct vm_area_struct *vma) drm_vma_offset_unlock_lookup(dev->vma_offset_manager); if (!obj) - return -EINVAL; + return ERR_PTR(-EINVAL); if (!drm_vma_node_is_allowed(node, priv)) { drm_gem_object_put(obj); - return -EACCES; + return ERR_PTR(-EACCES); } - ret = drm_gem_mmap_obj(obj, drm_vma_node_size(node) << PAGE_SHIFT, + return obj; +} + +/** + * drm_gem_get_unmapped_area - get memory mapping region routine for GEM objects + * @filp: DRM file pointer + * @uaddr: User address hint + * @len: Mapping length + * @pgoff: Offset (in pages) + * @flags: Mapping flags + * + * If a driver supports GEM object mapping, before ending up in drm_gem_mmap(), + * mmap calls on the DRM file descriptor will first try to find a free linear + * address space large enough for a mapping. Since GEM objects are backed by + * shmem buffers, this should preferably be handled by the shmem virtual memory + * filesystem which can appropriately align addresses to huge page sizes when + * needed. + * + * Look up the GEM object based on the offset passed in (vma->vm_pgoff will + * contain the fake offset we created) and call shmem_get_unmapped_area() with + * the right file pointer. + * + * If a GEM object is not available at the given offset or if the caller is not + * granted access to it, fall back to mm_get_unmapped_area(). + */ +unsigned long drm_gem_get_unmapped_area(struct file *filp, unsigned long uaddr, + unsigned long len, unsigned long pgoff, + unsigned long flags) +{ + struct drm_gem_object *obj; + unsigned long ret; + + obj = drm_gem_object_lookup_at_offset(filp, pgoff, len >> PAGE_SHIFT); + if (IS_ERR(obj) || !obj->filp || !obj->filp->f_op->get_unmapped_area) + return mm_get_unmapped_area(current->mm, filp, uaddr, len, 0, + flags); + + ret = obj->filp->f_op->get_unmapped_area(obj->filp, uaddr, len, 0, + flags); + + drm_gem_object_put(obj); + + return ret; +} +EXPORT_SYMBOL_GPL(drm_gem_get_unmapped_area); + +/** + * drm_gem_mmap - memory map routine for GEM objects + * @filp: DRM file pointer + * @vma: VMA for the area to be mapped + * + * If a driver supports GEM object mapping, mmap calls on the DRM file + * descriptor will end up here. + * + * Look up the GEM object based on the offset passed in (vma->vm_pgoff will + * contain the fake offset we created) and map it with a call to + * drm_gem_mmap_obj(). + * + * If the caller is not granted access to the buffer object, the mmap will fail + * with EACCES. Please see the vma manager for more information. + */ +int drm_gem_mmap(struct file *filp, struct vm_area_struct *vma) +{ + struct drm_gem_object *obj; + int ret; + + obj = drm_gem_object_lookup_at_offset(filp, vma->vm_pgoff, + vma_pages(vma)); + if (IS_ERR(obj)) + return PTR_ERR(obj); + + ret = drm_gem_mmap_obj(obj, + drm_vma_node_size(&obj->vma_node) << PAGE_SHIFT, vma); drm_gem_object_put(obj); diff --git a/include/drm/drm_gem.h b/include/drm/drm_gem.h index 8d48d2af2649..7c8bd67d087c 100644 --- a/include/drm/drm_gem.h +++ b/include/drm/drm_gem.h @@ -469,6 +469,7 @@ struct drm_gem_object { .poll = drm_poll,\ .read = drm_read,\ .llseek = noop_llseek,\ + .get_unmapped_area = drm_gem_get_unmapped_area,\ .mmap = drm_gem_mmap, \ .fop_flags = FOP_UNSIGNED_OFFSET @@ -506,6 +507,9 @@ void drm_gem_vm_close(struct vm_area_struct *vma); int drm_gem_mmap_obj(struct drm_gem_object *obj, unsigned long obj_size, struct vm_area_struct *vma); int drm_gem_mmap(struct file *filp, struct vm_area_struct *vma); +unsigned long drm_gem_get_unmapped_area(struct file *filp, unsigned long uaddr, + unsigned long len, unsigned long pgoff, + unsigned long flags); /** * drm_gem_object_get - acquire a GEM buffer object reference