1 files changed, 168 insertions, 0 deletions
diff --git a/include/drm/drm_gem_shmem_helper.h b/include/drm/drm_gem_shmem_helper.h
new file mode 100644
index 000000000..5381f0c8c
--- /dev/null
+++ b/include/drm/drm_gem_shmem_helper.h
@@ -0,0 +1,168 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef __DRM_GEM_SHMEM_HELPER_H__
+#define __DRM_GEM_SHMEM_HELPER_H__
+
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/mutex.h>
+
+#include <drm/drm_file.h>
+#include <drm/drm_gem.h>
+#include <drm/drm_ioctl.h>
+#include <drm/drm_prime.h>
+
+struct dma_buf_attachment;
+struct drm_mode_create_dumb;
+struct drm_printer;
+struct sg_table;
+
+/**
+ * struct drm_gem_shmem_object - GEM object backed by shmem
+ */
+struct drm_gem_shmem_object {
+	/**
+	 * @base: Base GEM object
+	 */
+	struct drm_gem_object base;
+
+	/**
+	 * @pages_lock: Protects the page table and use count
+	 */
+	struct mutex pages_lock;
+
+	/**
+	 * @pages: Page table
+	 */
+	struct page **pages;
+
+	/**
+	 * @pages_use_count:
+	 *
+	 * Reference count on the pages table.
+	 * The pages are put when the count reaches zero.
+	 */
+	unsigned int pages_use_count;
+
+	/**
+	 * @madv: State for madvise
+	 *
+	 * 0 is active/inuse.
+	 * A negative value is the object is purged.
+	 * Positive values are driver specific and not used by the helpers.
+	 */
+	int madv;
+
+	/**
+	 * @madv_list: List entry for madvise tracking
+	 *
+	 * Typically used by drivers to track purgeable objects
+	 */
+	struct list_head madv_list;
+
+	/**
+	 * @pages_mark_dirty_on_put:
+	 *
+	 * Mark pages as dirty when they are put.
+	 */
+	unsigned int pages_mark_dirty_on_put    : 1;
+
+	/**
+	 * @pages_mark_accessed_on_put:
+	 *
+	 * Mark pages as accessed when they are put.
+	 */
+	unsigned int pages_mark_accessed_on_put : 1;
+
+	/**
+	 * @sgt: Scatter/gather table for imported PRIME buffers
+	 */
+	struct sg_table *sgt;
+
+	/**
+	 * @vmap_lock: Protects the vmap address and use count
+	 */
+	struct mutex vmap_lock;
+
+	/**
+	 * @vaddr: Kernel virtual address of the backing memory
+	 */
+	void *vaddr;
+
+	/**
+	 * @vmap_use_count:
+	 *
+	 * Reference count on the virtual address.
+	 * The address are un-mapped when the count reaches zero.
+	 */
+	unsigned int vmap_use_count;
+
+	/**
+	 * @map_cached: map object cached (instead of using writecombine).
+	 */
+	bool map_cached;
+};
+
+#define to_drm_gem_shmem_obj(obj) \
+	container_of(obj, struct drm_gem_shmem_object, base)
+
+struct drm_gem_shmem_object *drm_gem_shmem_create(struct drm_device *dev, size_t size);
+void drm_gem_shmem_free_object(struct drm_gem_object *obj);
+
+int drm_gem_shmem_get_pages(struct drm_gem_shmem_object *shmem);
+void drm_gem_shmem_put_pages(struct drm_gem_shmem_object *shmem);
+int drm_gem_shmem_pin(struct drm_gem_object *obj);
+void drm_gem_shmem_unpin(struct drm_gem_object *obj);
+void *drm_gem_shmem_vmap(struct drm_gem_object *obj);
+void drm_gem_shmem_vunmap(struct drm_gem_object *obj, void *vaddr);
+
+int drm_gem_shmem_madvise(struct drm_gem_object *obj, int madv);
+
+static inline bool drm_gem_shmem_is_purgeable(struct drm_gem_shmem_object *shmem)
+{
+	return (shmem->madv > 0) &&
+		!shmem->vmap_use_count && shmem->sgt &&
+		!shmem->base.dma_buf && !shmem->base.import_attach;
+}
+
+void drm_gem_shmem_purge_locked(struct drm_gem_object *obj);
+bool drm_gem_shmem_purge(struct drm_gem_object *obj);
+
+struct drm_gem_shmem_object *
+drm_gem_shmem_create_with_handle(struct drm_file *file_priv,
+				 struct drm_device *dev, size_t size,
+				 uint32_t *handle);
+
+struct drm_gem_object *
+drm_gem_shmem_create_object_cached(struct drm_device *dev, size_t size);
+
+int drm_gem_shmem_dumb_create(struct drm_file *file, struct drm_device *dev,
+			      struct drm_mode_create_dumb *args);
+
+int drm_gem_shmem_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma);
+
+void drm_gem_shmem_print_info(struct drm_printer *p, unsigned int indent,
+			      const struct drm_gem_object *obj);
+
+struct sg_table *drm_gem_shmem_get_sg_table(struct drm_gem_object *obj);
+struct drm_gem_object *
+drm_gem_shmem_prime_import_sg_table(struct drm_device *dev,
+				    struct dma_buf_attachment *attach,
+				    struct sg_table *sgt);
+
+struct sg_table *drm_gem_shmem_get_pages_sgt(struct drm_gem_object *obj);
+
+/**
+ * DRM_GEM_SHMEM_DRIVER_OPS - Default shmem GEM operations
+ *
+ * This macro provides a shortcut for setting the shmem GEM operations in
+ * the &drm_driver structure.
+ */
+#define DRM_GEM_SHMEM_DRIVER_OPS \
+	.prime_handle_to_fd	= drm_gem_prime_handle_to_fd, \
+	.prime_fd_to_handle	= drm_gem_prime_fd_to_handle, \
+	.gem_prime_import_sg_table = drm_gem_shmem_prime_import_sg_table, \
+	.gem_prime_mmap		= drm_gem_prime_mmap, \
+	.dumb_create		= drm_gem_shmem_dumb_create
+
+#endif /* __DRM_GEM_SHMEM_HELPER_H__ */