linux/include/drm/drm_gem_shmem_helper.h
Noralf Trønnes 2194a63a81 drm: Add library for shmem backed GEM objects
This adds a library for shmem backed GEM objects.

v8:
- export drm_gem_shmem_create_with_handle
- call mapping_set_gfp_mask to set default zone to GFP_HIGHUSER
- Add helper drm_gem_shmem_get_pages_sgt()

v7:
- Use write-combine for mmap instead. This is the more common
  case. (robher)

v6:
- Fix uninitialized variable issue in an error path (anholt).
- Add a drm_gem_shmem_vm_open() to the fops to get proper refcounting
  of the pages (anholt).

v5:
- Drop drm_gem_shmem_prime_mmap() (Daniel Vetter)
- drm_gem_shmem_mmap(): Subtract drm_vma_node_start() to get the real
  vma->vm_pgoff
- drm_gem_shmem_fault(): Use vmf->pgoff now that vma->vm_pgoff is correct

v4:
- Drop cache modes (Thomas Hellstrom)
- Add a GEM attached vtable

v3:
- Grammar (Sam Ravnborg)
- s/drm_gem_shmem_put_pages_unlocked/drm_gem_shmem_put_pages_locked/
  (Sam Ravnborg)
- Add debug output in error path (Sam Ravnborg)

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Eric Anholt <eric@anholt.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20190313004344.24169-1-robh@kernel.org
2019-03-14 12:06:44 -07:00

160 lines
4.4 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;
/**
* @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;
};
#define to_drm_gem_shmem_obj(obj) \
container_of(obj, struct drm_gem_shmem_object, base)
/**
* DEFINE_DRM_GEM_SHMEM_FOPS() - Macro to generate file operations for shmem drivers
* @name: name for the generated structure
*
* This macro autogenerates a suitable &struct file_operations for shmem based
* drivers, which can be assigned to &drm_driver.fops. Note that this structure
* cannot be shared between drivers, because it contains a reference to the
* current module using THIS_MODULE.
*
* Note that the declaration is already marked as static - if you need a
* non-static version of this you're probably doing it wrong and will break the
* THIS_MODULE reference by accident.
*/
#define DEFINE_DRM_GEM_SHMEM_FOPS(name) \
static const struct file_operations name = {\
.owner = THIS_MODULE,\
.open = drm_open,\
.release = drm_release,\
.unlocked_ioctl = drm_ioctl,\
.compat_ioctl = drm_compat_ioctl,\
.poll = drm_poll,\
.read = drm_read,\
.llseek = noop_llseek,\
.mmap = drm_gem_shmem_mmap, \
}
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);
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);
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 file *filp, struct vm_area_struct *vma);
extern const struct vm_operations_struct drm_gem_shmem_vm_ops;
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__ */