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/**************************************************************************
*
* Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
* All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sub license, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice (including the
* next paragraph) shall be included in all copies or substantial portions
* of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
* THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
* DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
* OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
* USE OR OTHER DEALINGS IN THE SOFTWARE.
*
**************************************************************************/
/*
* Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
*/
#ifndef _TTM_BO_API_H_
#define _TTM_BO_API_H_
#include <drm/drm_gem.h>
#include <drm/drm_hashtab.h>
#include <drm/drm_vma_manager.h>
#include <linux/kref.h>
#include <linux/list.h>
#include <linux/wait.h>
#include <linux/mutex.h>
#include <linux/mm.h>
#include <linux/bitmap.h>
#include <linux/dma-resv.h>
struct ttm_bo_global;
struct ttm_bo_device;
struct drm_mm_node;
struct ttm_placement;
struct ttm_place;
struct ttm_lru_bulk_move;
/**
* struct ttm_bus_placement
*
* @addr: mapped virtual address
* @base: bus base address
* @is_iomem: is this io memory ?
* @size: size in byte
* @offset: offset from the base address
* @io_reserved_vm: The VM system has a refcount in @io_reserved_count
* @io_reserved_count: Refcounting the numbers of callers to ttm_mem_io_reserve
*
* Structure indicating the bus placement of an object.
*/
struct ttm_bus_placement {
void *addr;
phys_addr_t base;
unsigned long size;
unsigned long offset;
bool is_iomem;
bool io_reserved_vm;
uint64_t io_reserved_count;
};
/**
* struct ttm_mem_reg
*
* @mm_node: Memory manager node.
* @size: Requested size of memory region.
* @num_pages: Actual size of memory region in pages.
* @page_alignment: Page alignment.
* @placement: Placement flags.
* @bus: Placement on io bus accessible to the CPU
*
* Structure indicating the placement and space resources used by a
* buffer object.
*/
struct ttm_mem_reg {
void *mm_node;
unsigned long start;
unsigned long size;
unsigned long num_pages;
uint32_t page_alignment;
uint32_t mem_type;
uint32_t placement;
struct ttm_bus_placement bus;
};
/**
* enum ttm_bo_type
*
* @ttm_bo_type_device: These are 'normal' buffers that can
* be mmapped by user space. Each of these bos occupy a slot in the
* device address space, that can be used for normal vm operations.
*
* @ttm_bo_type_kernel: These buffers are like ttm_bo_type_device buffers,
* but they cannot be accessed from user-space. For kernel-only use.
*
* @ttm_bo_type_sg: Buffer made from dmabuf sg table shared with another
* driver.
*/
enum ttm_bo_type {
ttm_bo_type_device,
ttm_bo_type_kernel,
ttm_bo_type_sg
};
struct ttm_tt;
/**
* struct ttm_buffer_object
*
* @base: drm_gem_object superclass data.
* @bdev: Pointer to the buffer object device structure.
* @type: The bo type.
* @destroy: Destruction function. If NULL, kfree is used.
* @num_pages: Actual number of pages.
* @acc_size: Accounted size for this object.
* @kref: Reference count of this buffer object. When this refcount reaches
* zero, the object is put on the delayed delete list.
* @list_kref: List reference count of this buffer object. This member is
* used to avoid destruction while the buffer object is still on a list.
* Lru lists may keep one refcount, the delayed delete list, and kref != 0
* keeps one refcount. When this refcount reaches zero,
* the object is destroyed.
* @mem: structure describing current placement.
* @persistent_swap_storage: Usually the swap storage is deleted for buffers
* pinned in physical memory. If this behaviour is not desired, this member
* holds a pointer to a persistent shmem object.
* @ttm: TTM structure holding system pages.
* @evicted: Whether the object was evicted without user-space knowing.
* @cpu_writes: For synchronization. Number of cpu writers.
* @lru: List head for the lru list.
* @ddestroy: List head for the delayed destroy list.
* @swap: List head for swap LRU list.
* @moving: Fence set when BO is moving
* @offset: The current GPU offset, which can have different meanings
* depending on the memory type. For SYSTEM type memory, it should be 0.
* @cur_placement: Hint of current placement.
* @wu_mutex: Wait unreserved mutex.
*
* Base class for TTM buffer object, that deals with data placement and CPU
* mappings. GPU mappings are really up to the driver, but for simpler GPUs
* the driver can usually use the placement offset @offset directly as the
* GPU virtual address. For drivers implementing multiple
* GPU memory manager contexts, the driver should manage the address space
* in these contexts separately and use these objects to get the correct
* placement and caching for these GPU maps. This makes it possible to use
* these objects for even quite elaborate memory management schemes.
* The destroy member, the API visibility of this object makes it possible
* to derive driver specific types.
*/
struct ttm_buffer_object {
struct drm_gem_object base;
/**
* Members constant at init.
*/
struct ttm_bo_device *bdev;
enum ttm_bo_type type;
void (*destroy) (struct ttm_buffer_object *);
unsigned long num_pages;
size_t acc_size;
/**
* Members not needing protection.
*/
struct kref kref;
struct kref list_kref;
/**
* Members protected by the bo::resv::reserved lock.
*/
struct ttm_mem_reg mem;
struct file *persistent_swap_storage;
struct ttm_tt *ttm;
bool evicted;
/**
* Members protected by the bo::reserved lock only when written to.
*/
atomic_t cpu_writers;
/**
* Members protected by the bdev::lru_lock.
*/
struct list_head lru;
struct list_head ddestroy;
struct list_head swap;
struct list_head io_reserve_lru;
/**
* Members protected by a bo reservation.
*/
struct dma_fence *moving;
unsigned priority;
/**
* Special members that are protected by the reserve lock
* and the bo::lock when written to. Can be read with
* either of these locks held.
*/
uint64_t offset; /* GPU address space is independent of CPU word size */
struct sg_table *sg;
struct mutex wu_mutex;
};
/**
* struct ttm_bo_kmap_obj
*
* @virtual: The current kernel virtual address.
* @page: The page when kmap'ing a single page.
* @bo_kmap_type: Type of bo_kmap.
*
* Object describing a kernel mapping. Since a TTM bo may be located
* in various memory types with various caching policies, the
* mapping can either be an ioremap, a vmap, a kmap or part of a
* premapped region.
*/
#define TTM_BO_MAP_IOMEM_MASK 0x80
struct ttm_bo_kmap_obj {
void *virtual;
struct page *page;
enum {
ttm_bo_map_iomap = 1 | TTM_BO_MAP_IOMEM_MASK,
ttm_bo_map_vmap = 2,
ttm_bo_map_kmap = 3,
ttm_bo_map_premapped = 4 | TTM_BO_MAP_IOMEM_MASK,
} bo_kmap_type;
struct ttm_buffer_object *bo;
};
/**
* struct ttm_operation_ctx
*
* @interruptible: Sleep interruptible if sleeping.
* @no_wait_gpu: Return immediately if the GPU is busy.
* @resv: Reservation object to allow reserved evictions with.
* @flags: Including the following flags
*
* Context for TTM operations like changing buffer placement or general memory
* allocation.
*/
struct ttm_operation_ctx {
bool interruptible;
bool no_wait_gpu;
struct dma_resv *resv;
uint64_t bytes_moved;
uint32_t flags;
};
/* Allow eviction of reserved BOs */
#define TTM_OPT_FLAG_ALLOW_RES_EVICT 0x1
/* when serving page fault or suspend, allow alloc anyway */
#define TTM_OPT_FLAG_FORCE_ALLOC 0x2
/**
* ttm_bo_get - reference a struct ttm_buffer_object
*
* @bo: The buffer object.
*/
static inline void ttm_bo_get(struct ttm_buffer_object *bo)
{
kref_get(&bo->kref);
}
/**
* ttm_bo_get_unless_zero - reference a struct ttm_buffer_object unless
* its refcount has already reached zero.
* @bo: The buffer object.
*
* Used to reference a TTM buffer object in lookups where the object is removed
* from the lookup structure during the destructor and for RCU lookups.
*
* Returns: @bo if the referencing was successful, NULL otherwise.
*/
static inline __must_check struct ttm_buffer_object *
ttm_bo_get_unless_zero(struct ttm_buffer_object *bo)
{
if (!kref_get_unless_zero(&bo->kref))
return NULL;
return bo;
}
/**
* ttm_bo_wait - wait for buffer idle.
*
* @bo: The buffer object.
* @interruptible: Use interruptible wait.
* @no_wait: Return immediately if buffer is busy.
*
* This function must be called with the bo::mutex held, and makes
* sure any previous rendering to the buffer is completed.
* Note: It might be necessary to block validations before the
* wait by reserving the buffer.
* Returns -EBUSY if no_wait is true and the buffer is busy.
* Returns -ERESTARTSYS if interrupted by a signal.
*/
int ttm_bo_wait(struct ttm_buffer_object *bo, bool interruptible, bool no_wait);
/**
* ttm_bo_mem_compat - Check if proposed placement is compatible with a bo
*
* @placement: Return immediately if buffer is busy.
* @mem: The struct ttm_mem_reg indicating the region where the bo resides
* @new_flags: Describes compatible placement found
*
* Returns true if the placement is compatible
*/
bool ttm_bo_mem_compat(struct ttm_placement *placement, struct ttm_mem_reg *mem,
uint32_t *new_flags);
/**
* ttm_bo_validate
*
* @bo: The buffer object.
* @placement: Proposed placement for the buffer object.
* @ctx: validation parameters.
*
* Changes placement and caching policy of the buffer object
* according proposed placement.
* Returns
* -EINVAL on invalid proposed placement.
* -ENOMEM on out-of-memory condition.
* -EBUSY if no_wait is true and buffer busy.
* -ERESTARTSYS if interrupted by a signal.
*/
int ttm_bo_validate(struct ttm_buffer_object *bo,
struct ttm_placement *placement,
struct ttm_operation_ctx *ctx);
/**
* ttm_bo_put
*
* @bo: The buffer object.
*
* Unreference a buffer object.
*/
void
|