swh:1:snp:32555a3fd8878f019c2ebd6c964bc1edcaeff337
Tip revision: 5816b3e6577eaa676ceb00a848f0fd65fe2adc29 authored by Linus Torvalds on 26 September 2021, 21:08:19 UTC
Linux 5.15-rc3
Linux 5.15-rc3
Tip revision: 5816b3e
ttm_bo_api.h
/**************************************************************************
*
* 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>
#include "ttm_resource.h"
struct ttm_global;
struct ttm_device;
struct dma_buf_map;
struct drm_mm_node;
struct ttm_placement;
struct ttm_place;
struct ttm_lru_bulk_move;
/**
* 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.
* @page_alignment: Page alignment.
* @destroy: Destruction function. If NULL, kfree is used.
* @num_pages: Actual number of pages.
* @kref: Reference count of this buffer object. When this refcount reaches
* zero, the object is destroyed or put on the delayed delete list.
* @mem: structure describing current placement.
* @ttm: TTM structure holding system pages.
* @evicted: Whether the object was evicted without user-space knowing.
* @deleted: True if the object is only a zombie and already deleted.
* @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.
*
* 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;
/**
* Members protected by the bdev::lru_lock.
*/
struct list_head lru;
struct list_head ddestroy;
/**
* Members protected by a bo reservation.
*/
struct dma_fence *moving;
unsigned priority;
unsigned pin_count;
/**
* 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.
*/
struct sg_table *sg;
};
/**
* 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.
* @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.
*
* 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;
};
/**
* 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);
static inline int ttm_bo_wait_ctx(struct ttm_buffer_object *bo, struct ttm_operation_ctx *ctx)
{
return ttm_bo_wait(bo, ctx->interruptible, ctx->no_wait_gpu);
}
/**
* ttm_bo_mem_compat - Check if proposed placement is compatible with a bo
*
* @placement: Return immediately if buffer is busy.
* @mem: The struct ttm_resource 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_resource *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 ttm_bo_put(struct ttm_buffer_object *bo);
/**
* ttm_bo_move_to_lru_tail
*
* @bo: The buffer object.
* @mem: Resource object.
* @bulk: optional bulk move structure to remember BO positions
*
* Move this BO to the tail of all lru lists used to lookup and reserve an
* object. This function must be called with struct ttm_global::lru_lock
* held, and is used to make a BO less likely to be considered for eviction.
*/
void ttm_bo_move_to_lru_tail(struct ttm_buffer_object *bo,
struct ttm_resource *mem,
struct ttm_lru_bulk_move *bulk);
/**
* ttm_bo_bulk_move_lru_tail
*
* @bulk: bulk move structure
*
* Bulk move BOs to the LRU tail, only valid to use when driver makes sure that
* BO order never changes. Should be called with ttm_global::lru_lock held.
*/
void ttm_bo_bulk_move_lru_tail(struct ttm_lru_bulk_move *bulk);
/**
* ttm_bo_lock_delayed_workqueue
*
* Prevent the delayed workqueue from running.
* Returns
* True if the workqueue was queued at the time
*/
int ttm_bo_lock_delayed_workqueue(struct ttm_device *bdev);
/**
* ttm_bo_unlock_delayed_workqueue
*
* Allows the delayed workqueue to run.
*/
void ttm_bo_unlock_delayed_workqueue(struct ttm_device *bdev, int resched);
/**
* ttm_bo_eviction_valuable
*
* @bo: The buffer object to evict
* @place: the placement we need to make room for
*
* Check if it is valuable to evict the BO to make room for the given placement.
*/
bool ttm_bo_eviction_valuable(struct ttm_buffer_object *bo,
const struct ttm_place *place);
/**
* ttm_bo_init_reserved
*
* @bdev: Pointer to a ttm_device struct.
* @bo: Pointer to a ttm_buffer_object to be initialized.
* @size: Requested size of buffer object.
* @type: Requested type of buffer object.
* @flags: Initial placement flags.
* @page_alignment: Data alignment in pages.
* @ctx: TTM operation context for memory allocation.
* @resv: Pointer to a dma_resv, or NULL to let ttm allocate one.
* @destroy: Destroy function. Use NULL for kfree().
*
* This function initializes a pre-allocated struct ttm_buffer_object.
* As this object may be part of a larger structure, this function,
* together with the @destroy function,
* enables driver-specific objects derived from a ttm_buffer_object.
*
* On successful return, the caller owns an object kref to @bo. The kref and
* list_kref are usually set to 1, but note that in some situations, other
* tasks may already be holding references to @bo as well.
* Furthermore, if resv == NULL, the buffer's reservation lock will be held,
* and it is the caller's responsibility to call ttm_bo_unreserve.
*
* If a failure occurs, the function will call the @destroy function, or
* kfree() if @destroy is NULL. Thus, after a failure, dereferencing @bo is
* illegal and will likely cause memory corruption.
*
* Returns
* -ENOMEM: Out of memory.
* -EINVAL: Invalid placement flags.
* -ERESTARTSYS: Interrupted by signal while sleeping waiting for resources.
*/
int ttm_bo_init_reserved(struct ttm_device *bdev,
struct ttm_buffer_object *bo,
size_t size, enum ttm_bo_type type,
struct ttm_placement *placement,
uint32_t page_alignment,
struct ttm_operation_ctx *ctx,
struct sg_table *sg, struct dma_resv *resv,
void (*destroy) (struct ttm_buffer_object *));
/**
* ttm_bo_init
*
* @bdev: Pointer to a ttm_device struct.
* @bo: Pointer to a ttm_buffer_object to be initialized.
* @size: Requested size of buffer object.
* @type: Requested type of buffer object.
* @flags: Initial placement flags.
* @page_alignment: Data alignment in pages.
* @interruptible: If needing to sleep to wait for GPU resources,
* sleep interruptible.
* pinned in physical memory. If this behaviour is not desired, this member
* holds a pointer to a persistent shmem object. Typically, this would
* point to the shmem object backing a GEM object if TTM is used to back a
* GEM user interface.
* @resv: Pointer to a dma_resv, or NULL to let ttm allocate one.
* @destroy: Destroy function. Use NULL for kfree().
*
* This function initializes a pre-allocated struct ttm_buffer_object.
* As this object may be part of a larger structure, this function,
* together with the @destroy function,
* enables driver-specific objects derived from a ttm_buffer_object.
*
* On successful return, the caller owns an object kref to @bo. The kref and
* list_kref are usually set to 1, but note that in some situations, other
* tasks may already be holding references to @bo as well.
*
* If a failure occurs, the function will call the @destroy function, or
* kfree() if @destroy is NULL. Thus, after a failure, dereferencing @bo is
* illegal and will likely cause memory corruption.
*
* Returns
* -ENOMEM: Out of memory.
* -EINVAL: Invalid placement flags.
* -ERESTARTSYS: Interrupted by signal while sleeping waiting for resources.
*/
int ttm_bo_init(struct ttm_device *bdev, struct ttm_buffer_object *bo,
size_t size, enum ttm_bo_type type,
struct ttm_placement *placement,
uint32_t page_alignment, bool interrubtible,
struct sg_table *sg, struct dma_resv *resv,
void (*destroy) (struct ttm_buffer_object *));
/**
* 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;
}
/**
* ttm_bo_kmap
*
* @bo: The buffer object.
* @start_page: The first page to map.
* @num_pages: Number of pages to map.
* @map: pointer to a struct ttm_bo_kmap_obj representing the map.
*
* Sets up a kernel virtual mapping, using ioremap, vmap or kmap to the
* data in the buffer object. The ttm_kmap_obj_virtual function can then be
* used to obtain a virtual address to the data.
*
* Returns
* -ENOMEM: Out of memory.
* -EINVAL: Invalid range.
*/
int ttm_bo_kmap(struct ttm_buffer_object *bo, unsigned long start_page,
unsigned long num_pages, struct ttm_bo_kmap_obj *map);
/**
* ttm_bo_kunmap
*
* @map: Object describing the map to unmap.
*
* Unmaps a kernel map set up by ttm_bo_kmap.
*/
void ttm_bo_kunmap(struct ttm_bo_kmap_obj *map);
/**
* ttm_bo_vmap
*
* @bo: The buffer object.
* @map: pointer to a struct dma_buf_map representing the map.
*
* Sets up a kernel virtual mapping, using ioremap or vmap to the
* data in the buffer object. The parameter @map returns the virtual
* address as struct dma_buf_map. Unmap the buffer with ttm_bo_vunmap().
*
* Returns
* -ENOMEM: Out of memory.
* -EINVAL: Invalid range.
*/
int ttm_bo_vmap(struct ttm_buffer_object *bo, struct dma_buf_map *map);
/**
* ttm_bo_vunmap
*
* @bo: The buffer object.
* @map: Object describing the map to unmap.
*
* Unmaps a kernel map set up by ttm_bo_vmap().
*/
void ttm_bo_vunmap(struct ttm_buffer_object *bo, struct dma_buf_map *map);
/**
* ttm_bo_mmap_obj - mmap memory backed by a ttm buffer object.
*
* @vma: vma as input from the fbdev mmap method.
* @bo: The bo backing the address space.
*
* Maps a buffer object.
*/
int ttm_bo_mmap_obj(struct vm_area_struct *vma, struct ttm_buffer_object *bo);
/**
* ttm_bo_io
*
* @bdev: Pointer to the struct ttm_device.
* @filp: Pointer to the struct file attempting to read / write.
* @wbuf: User-space pointer to address of buffer to write. NULL on read.
* @rbuf: User-space pointer to address of buffer to read into.
* Null on write.
* @count: Number of bytes to read / write.
* @f_pos: Pointer to current file position.
* @write: 1 for read, 0 for write.
*
* This function implements read / write into ttm buffer objects, and is
* intended to
* be called from the fops::read and fops::write method.
* Returns:
* See man (2) write, man(2) read. In particular,
* the function may return -ERESTARTSYS if
* interrupted by a signal.
*/
ssize_t ttm_bo_io(struct ttm_device *bdev, struct file *filp,
const char __user *wbuf, char __user *rbuf,
size_t count, loff_t *f_pos, bool write);
int ttm_bo_swapout(struct ttm_buffer_object *bo, struct ttm_operation_ctx *ctx,
gfp_t gfp_flags);
/**
* ttm_bo_pin - Pin the buffer object.
* @bo: The buffer object to pin
*
* Make sure the buffer is not evicted any more during memory pressure.
*/
static inline void ttm_bo_pin(struct ttm_buffer_object *bo)
{
dma_resv_assert_held(bo->base.resv);
WARN_ON_ONCE(!kref_read(&bo->kref));
++bo->pin_count;
}
/**
* ttm_bo_unpin - Unpin the buffer object.
* @bo: The buffer object to unpin
*
* Allows the buffer object to be evicted again during memory pressure.
*/
static inline void ttm_bo_unpin(struct ttm_buffer_object *bo)
{
dma_resv_assert_held(bo->base.resv);
WARN_ON_ONCE(!kref_read(&bo->kref));
if (bo->pin_count)
--bo->pin_count;
else
WARN_ON_ONCE(true);
}
int ttm_mem_evict_first(struct ttm_device *bdev,
struct ttm_resource_manager *man,
const struct ttm_place *place,
struct ttm_operation_ctx *ctx,
struct ww_acquire_ctx *ticket);
/* Default number of pre-faulted pages in the TTM fault handler */
#define TTM_BO_VM_NUM_PREFAULT 16
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,
pgoff_t fault_page_size);
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);
bool ttm_bo_delayed_delete(struct ttm_device *bdev, bool remove_all);
vm_fault_t ttm_bo_vm_dummy_page(struct vm_fault *vmf, pgprot_t prot);
#endif