linux/include/drm/drm_gem_shmem_helper.h
Thomas Zimmermann a193f3b4e0 drm/shmem-helper: Pass GEM shmem object in public interfaces
Change all GEM SHMEM object functions that receive a GEM object
of type struct drm_gem_object to expect an object of type
struct drm_gem_shmem_object instead.

This change reduces the number of upcasts from struct drm_gem_object
by moving them into callers. The C compiler can now verify that the
GEM SHMEM functions are called with the correct type.

For consistency, the patch also renames drm_gem_shmem_free_object to
drm_gem_shmem_free. It further updates documentation for a number of
functions.

v3:
	* fix docs for drm_gem_shmem_object_free()
v2:
	* mention _object_ callbacks in docs (Daniel)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20211108093149.7226-4-tzimmermann@suse.de
2021-11-15 11:46:13 +01:00

294 lines
8.3 KiB
C

/* 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_wc: map object write-combined (instead of using shmem defaults).
*/
bool map_wc;
};
#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(struct drm_gem_shmem_object *shmem);
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_shmem_object *shmem);
void drm_gem_shmem_unpin(struct drm_gem_shmem_object *shmem);
int drm_gem_shmem_vmap(struct drm_gem_shmem_object *shmem, struct dma_buf_map *map);
void drm_gem_shmem_vunmap(struct drm_gem_shmem_object *shmem, struct dma_buf_map *map);
int drm_gem_shmem_mmap(struct drm_gem_shmem_object *shmem, struct vm_area_struct *vma);
int drm_gem_shmem_madvise(struct drm_gem_shmem_object *shmem, 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_shmem_object *shmem);
bool drm_gem_shmem_purge(struct drm_gem_shmem_object *shmem);
struct sg_table *drm_gem_shmem_get_sg_table(struct drm_gem_shmem_object *shmem);
struct sg_table *drm_gem_shmem_get_pages_sgt(struct drm_gem_shmem_object *shmem);
void drm_gem_shmem_print_info(const struct drm_gem_shmem_object *shmem,
struct drm_printer *p, unsigned int indent);
/*
* GEM object functions
*/
/**
* drm_gem_shmem_object_free - GEM object function for drm_gem_shmem_free()
* @obj: GEM object to free
*
* This function wraps drm_gem_shmem_free(). Drivers that employ the shmem helpers
* should use it as their &drm_gem_object_funcs.free handler.
*/
static inline void drm_gem_shmem_object_free(struct drm_gem_object *obj)
{
struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
drm_gem_shmem_free(shmem);
}
/**
* drm_gem_shmem_object_print_info() - Print &drm_gem_shmem_object info for debugfs
* @p: DRM printer
* @indent: Tab indentation level
* @obj: GEM object
*
* This function wraps drm_gem_shmem_print_info(). Drivers that employ the shmem helpers should
* use this function as their &drm_gem_object_funcs.print_info handler.
*/
static inline void drm_gem_shmem_object_print_info(struct drm_printer *p, unsigned int indent,
const struct drm_gem_object *obj)
{
const struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
drm_gem_shmem_print_info(shmem, p, indent);
}
/**
* drm_gem_shmem_object_pin - GEM object function for drm_gem_shmem_pin()
* @obj: GEM object
*
* This function wraps drm_gem_shmem_pin(). Drivers that employ the shmem helpers should
* use it as their &drm_gem_object_funcs.pin handler.
*/
static inline int drm_gem_shmem_object_pin(struct drm_gem_object *obj)
{
struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
return drm_gem_shmem_pin(shmem);
}
/**
* drm_gem_shmem_object_unpin - GEM object function for drm_gem_shmem_unpin()
* @obj: GEM object
*
* This function wraps drm_gem_shmem_unpin(). Drivers that employ the shmem helpers should
* use it as their &drm_gem_object_funcs.unpin handler.
*/
static inline void drm_gem_shmem_object_unpin(struct drm_gem_object *obj)
{
struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
drm_gem_shmem_unpin(shmem);
}
/**
* drm_gem_shmem_object_get_sg_table - GEM object function for drm_gem_shmem_get_sg_table()
* @obj: GEM object
*
* This function wraps drm_gem_shmem_get_sg_table(). Drivers that employ the shmem helpers should
* use it as their &drm_gem_object_funcs.get_sg_table handler.
*
* Returns:
* A pointer to the scatter/gather table of pinned pages or NULL on failure.
*/
static inline struct sg_table *drm_gem_shmem_object_get_sg_table(struct drm_gem_object *obj)
{
struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
return drm_gem_shmem_get_sg_table(shmem);
}
/*
* drm_gem_shmem_object_vmap - GEM object function for drm_gem_shmem_vmap()
* @obj: GEM object
* @map: Returns the kernel virtual address of the SHMEM GEM object's backing store.
*
* This function wraps drm_gem_shmem_vmap(). Drivers that employ the shmem helpers should
* use it as their &drm_gem_object_funcs.vmap handler.
*
* Returns:
* 0 on success or a negative error code on failure.
*/
static inline int drm_gem_shmem_object_vmap(struct drm_gem_object *obj, struct dma_buf_map *map)
{
struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
return drm_gem_shmem_vmap(shmem, map);
}
/*
* drm_gem_shmem_object_vunmap - GEM object function for drm_gem_shmem_vunmap()
* @obj: GEM object
* @map: Kernel virtual address where the SHMEM GEM object was mapped
*
* This function wraps drm_gem_shmem_vunmap(). Drivers that employ the shmem helpers should
* use it as their &drm_gem_object_funcs.vunmap handler.
*/
static inline void drm_gem_shmem_object_vunmap(struct drm_gem_object *obj, struct dma_buf_map *map)
{
struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
drm_gem_shmem_vunmap(shmem, map);
}
/**
* drm_gem_shmem_object_mmap - GEM object function for drm_gem_shmem_mmap()
* @obj: GEM object
* @vma: VMA for the area to be mapped
*
* This function wraps drm_gem_shmem_mmap(). Drivers that employ the shmem helpers should
* use it as their &drm_gem_object_funcs.mmap handler.
*
* Returns:
* 0 on success or a negative error code on failure.
*/
static inline int drm_gem_shmem_object_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma)
{
struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
return drm_gem_shmem_mmap(shmem, vma);
}
/*
* Driver ops
*/
struct drm_gem_object *
drm_gem_shmem_prime_import_sg_table(struct drm_device *dev,
struct dma_buf_attachment *attach,
struct sg_table *sgt);
int drm_gem_shmem_dumb_create(struct drm_file *file, struct drm_device *dev,
struct drm_mode_create_dumb *args);
/**
* 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__ */