/**************************************************************************
*
* 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 <linux/kref.h>
#include <linux/list.h>
#include "ttm_device.h"
/* Default number of pre-faulted pages in the TTM fault handler */
#define TTM_BO_VM_NUM_PREFAULT 16
struct iosys_map;
struct ttm_global;
struct ttm_device;
struct ttm_placement;
struct ttm_place;
struct ttm_resource;
struct ttm_resource_manager;
struct ttm_tt;
/**
* 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_buffer_object
*
* @base: drm_gem_object superclass data.
* @bdev: Pointer to the buffer object device structure.
* @type: The bo type.
* @page_alignment: Page alignment.
* @destroy: Destruction function. If NULL, kfree is used.
* @kref: Reference count of this buffer object. When this refcount reaches
* zero, the object is destroyed or put on the delayed delete list.
* @resource: structure describing current placement.
* @ttm: TTM structure holding system pages.
* @deleted: True if the object is only a zombie and already deleted.
* @bulk_move: The bulk move object.
* @priority: Priority for LRU, BOs with lower priority are evicted first.
* @pin_count: Pin count.
*
* 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_device *bdev;
enum ttm_bo_type type;
uint32_t page_alignment;
void (*destroy) (struct ttm_buffer_object *);
/*
* Members not needing protection.
*/
struct kref kref;
/*
* Members protected by the bo::resv::reserved lock.
*/
struct ttm_resource *resource;
struct ttm_tt *ttm;
bool deleted;
struct ttm_lru_bulk_move *bulk_move;
unsigned priority;
unsigned pin_count;
/**
* @delayed_delete: Work item used when we can't delete the BO
* immediately
*/
struct work_struct delayed_delete;
/**
* @sg: external source of pages and DMA addresses, protected by the
* reservation lock.
*/
struct sg_table *sg;
};
#define TTM_BO_MAP_IOMEM_MASK 0x80
/**
* 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.
* @bo: The TTM BO.
*
* 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.
*/
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.
* @gfp_retry_mayfail: Set the __GFP_RETRY_MAYFAIL when allocation pages.
* @allow_res_evict: Allow eviction of reserved BOs. Can be used when multiple
* BOs share the same reservation object.
* @force_alloc: Don't check the memory account during suspend or CPU page
* faults. Should only be used by TTM internally.
* @resv: Reservation object to allow reserved evictions with.
* @bytes_moved: Statistics on how many bytes have been moved.
*
* Context for TTM operations like changing buffer placement or general memory
* allocation.
*/
struct ttm_operation_ctx {
bool interruptible;
bool no_wait_gpu;
bool gfp_retry_mayfail;
bool allow_res_evict;
bool force_alloc;
struct dma_resv *resv;
uint64_t bytes_moved;
};
struct ttm_lru_walk;
/** struct ttm_lru_walk_ops - Operations for a LRU walk. */
struct ttm_lru_walk_ops {
/**
* process_bo - Process this bo.
* @walk: struct ttm_lru_walk describing the walk.
* @bo: A locked and referenced buffer object.
*
* Return: Negative error code on error, User-defined positive value
* (typically, but not always, size of the processed bo) on success.
* On success, the returned values are summed by the walk and the
* walk exits when its target is met.
* 0 also indicates success, -EBUSY means this bo was skipped.
*/
s64 (*process_bo)(struct ttm_lru_walk *walk, struct ttm_buffer_object *bo);
};
/**
* struct ttm_lru_walk - Structure describing a LRU walk.
*/
struct ttm_lru_walk {
/** @ops: Pointer to the ops structure. */
const struct ttm_lru_walk_ops *ops;
/** @ctx: Pointer to the struct ttm_operation_ctx. */
struct ttm_operation_ctx *ctx;
/** @ticket: The struct ww_acquire_ctx if any. */
struct ww_acquire_ctx *ticket;
/** @trylock_only: Only use trylock for locking. */
bool trylock_only;
};
s64 ttm_lru_walk_for_evict(struct ttm_lru_walk *walk, struct ttm_device *bdev,
struct ttm_resource_manager *man, s64 target);
/**
* 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_reserve:
*
* @bo: A pointer to a struct ttm_buffer_object.
* @interruptible: Sleep interruptible if waiting.
* @no_wait: Don't sleep while trying to reserve, rather return -EBUSY.
* @ticket: ticket used to acquire the ww_mutex.
*
* Locks a buffer object for validation. (Or prevents other processes from
* locking it for validation), while taking a number of measures to prevent
* deadlocks.
*
* Returns:
* -EDEADLK: The reservation may cause a deadlock.
* Release all buffer reservations, wait for @bo to become unreserved and
* try again.
* -ERESTARTSYS: A wait for the buffer to become unreserved was interrupted by
* a signal. Release all buffer reservations and return to user-space.
* -EBUSY: The function needed to sleep, but @no_wait was true
* -EALREADY: Bo already reserved using @ticket. This error code will only
* be returned if @use_ticket is set to true.
*/
static inline int ttm_bo_reserve(struct ttm_buffer_object *bo,
bool interruptible, bool no_wait,
struct ww_acquire_ctx *ticket)
{
int ret = 0;
if (no_wait) {
bool success;
if (WARN_ON(ticket))
return -EBUSY;
success = dma_resv_trylock(bo->base.resv);
return success ? 0 : -EBUSY;
}
if (interruptible)
ret = dma_resv_lock_interruptible(bo->base.resv, ticket);
else
ret = dma_resv_lock(bo->base.resv, ticket);
if (ret == -EINTR)
return -ERESTARTSYS;
return ret;
}
/**
* ttm_bo_reserve_slowpath:
* @bo: A pointer to a struct ttm_buffer_object.
* @interruptible: Sleep interruptible if waiting.
* @ticket: Ticket used to acquire the ww_mutex.
*
* This is called after ttm_bo_reserve returns -EAGAIN and we backed off
* from all our other reservations. Because there are no other reservations
* held by us, this function cannot deadlock any more.
*/
static inline int ttm_bo_reserve_slowpath(struct ttm_buffer_object *bo,
bool interruptible,
struct ww_acquire_ctx *ticket)
{
if (interruptible) {
int ret = dma_resv_lock_slow_interruptible(bo->base.resv,
ticket);
if (ret == -EINTR)
ret = -ERESTARTSYS;
return ret;
}
dma_resv_lock_slow(bo->base.resv, ticket);
return 0;
}
void ttm_bo_move_to_lru_tail(struct ttm_buffer_object *bo);
static inline void
ttm_bo_move_to_lru_tail_unlocked(struct ttm_buffer_object *bo)
{
spin_lock(&bo->bdev->lru_lock);
ttm_bo_move_to_lru_tail(bo);
spin_unlock(&bo->bdev->lru_lock);
}
static inline void ttm_bo_assign_mem(struct ttm_buffer_object *bo,
struct ttm_resource *new_mem)
{
WARN_ON(bo->resource);
bo->resource = new_mem;
}
/**
* ttm_bo_move_null - assign memory for a buffer object.
* @bo: The bo to assign the memory to
* @new_mem: The memory to be assigned.
*
* Assign the memory from new_mem to the memory of the buffer object bo.
*/
static inline void ttm_bo_move_null(struct ttm_buffer_object *bo,
struct ttm_resource *new_mem)
{
ttm_resource_free(bo, &bo->resource);
ttm_bo_assign_mem(bo, new_mem);
}
/**
* ttm_bo_unreserve
*
* @bo: A pointer to a struct ttm_buffer_object.
*
* Unreserve a previous reservation of @bo.
*/
static inline void ttm_bo_unreserve(struct ttm_buffer_object *bo)
{
ttm_bo_move_to_lru_tail_unlocked(bo);
dma_resv_unlock(bo->base.resv);
}
/**
* ttm_kmap_obj_virtual
*
* @map: A struct ttm_bo_kmap_obj returned from ttm_bo_kmap.
* @is_iomem: Pointer to an integer that on return indicates 1 if the
* virtual map is io memory, 0 if normal memory.
*
* Returns the virtual address of a buffer object area mapped by ttm_bo_kmap.
* If *is_iomem is 1 on return, the virtual address points to an io memory area,
* that should strictly be accessed by the iowriteXX() and similar functions.
*/
static inline void *ttm_kmap_obj_virtual(struct ttm_bo_kmap_obj *map,
bool *is_iomem)
{
*is_iomem = !!(map->bo_kmap_type & TTM_BO_MAP_IOMEM_MASK);
return map->virtual;
}
int ttm_bo_wait_ctx(struct ttm_buffer_object *bo,
struct ttm_operation_ctx *ctx);
int ttm_bo_validate(struct ttm_buffer_object *bo,
struct ttm_placement *placement,
struct ttm_operation_ctx *ctx);
void ttm_bo_put(struct ttm_buffer_object *bo);
void ttm_bo_set_bulk_move(struct ttm_buffer_object *bo,
struct ttm_lru_bulk_move *bulk);
bool ttm_bo_eviction_valuable(struct ttm_buffer_object *bo,
const struct ttm_place *place);
int ttm_bo_init_reserved(struct ttm_device *bdev, struct ttm_buffer_object *bo,
enum ttm_bo_type type, struct ttm_placement *placement,
uint32_t alignment, struct ttm_operation_ctx *ctx,
struct sg_table *sg, struct dma_resv *resv,
void (*destroy)(struct ttm_buffer_object *));
int ttm_bo_init_validate(struct ttm_device *bdev, struct ttm_buffer_object *bo,
enum ttm_bo_type type, struct ttm_placement *placement,
uint32_t alignment, bool interruptible,
struct sg_table *sg, struct dma_resv *resv,
void (*destroy)(struct ttm_buffer_object *));
int ttm_bo_kmap(struct ttm_buffer_object *bo, unsigned long start_page,
unsigned long num_pages, struct ttm_bo_kmap_obj *map);
void ttm_bo_kunmap(struct ttm_bo_kmap_obj *map);
int ttm_bo_vmap(struct ttm_buffer_object *bo, struct iosys_map *map);
void ttm_bo_vunmap(struct ttm_buffer_object *bo, struct iosys_map *map);
int ttm_bo_mmap_obj(struct vm_area_struct *vma, struct ttm_buffer_object *bo);
s64 ttm_bo_swapout(struct ttm_device *bdev, struct ttm_operation_ctx *ctx,
struct ttm_resource_manager *man, gfp_t gfp_flags,
s64 target);
void ttm_bo_pin(struct ttm_buffer_object *bo);
void ttm_bo_unpin(struct ttm_buffer_object *bo);
int ttm_bo_evict_first(struct ttm_device *bdev,
struct ttm_resource_manager *man,
struct ttm_operation_ctx *ctx);
vm_fault_t ttm_bo_vm_reserve(struct ttm_buffer_object *bo,
struct vm_fault *vmf);
vm_fault_t ttm_bo_vm_fault_reserved(struct vm_fault *vmf,
pgprot_t prot,
pgoff_t num_prefault);
vm_fault_t ttm_bo_vm_fault(struct vm_fault *vmf);
void ttm_bo_vm_open(struct vm_area_struct *vma);
void ttm_bo_vm_close(struct vm_area_struct *vma);
int ttm_bo_vm_access(struct vm_area_struct *vma, unsigned long addr,
void *buf, int len, int write);
vm_fault_t ttm_bo_vm_dummy_page(struct vm_fault *vmf, pgprot_t prot);
int ttm_bo_mem_space(struct ttm_buffer_object *bo,
struct ttm_placement *placement,
struct ttm_resource **mem,
struct ttm_operation_ctx *ctx);
void ttm_bo_unmap_virtual(struct ttm_buffer_object *bo);
/*
* ttm_bo_util.c
*/
int ttm_mem_io_reserve(struct ttm_device *bdev,
struct ttm_resource *mem);
void ttm_mem_io_free(struct ttm_device *bdev,
struct ttm_resource *mem);
void ttm_move_memcpy(bool clear, u32 num_pages,
struct ttm_kmap_iter *dst_iter,
struct ttm_kmap_iter *src_iter);
int ttm_bo_move_memcpy(struct ttm_buffer_object *bo,
struct ttm_operation_ctx *ctx,
struct ttm_resource *new_mem);
int ttm_bo_move_accel_cleanup(struct ttm_buffer_object *bo,
struct dma_fence *fence, bool evict,
bool pipeline,
struct ttm_resource *new_mem);
void ttm_bo_move_sync_cleanup(struct ttm_buffer_object *bo,
struct ttm_resource *new_mem);
int ttm_bo_pipeline_gutting(struct ttm_buffer_object *bo);
pgprot_t ttm_io_prot(struct ttm_buffer_object *bo, struct ttm_resource *res,
pgprot_t tmp);
void ttm_bo_tt_destroy(struct ttm_buffer_object *bo);
#endif
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