/**************************************************************************
*
* 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_DRIVER_H_
#define _TTM_BO_DRIVER_H_
#include "ttm/ttm_bo_api.h"
#include "ttm/ttm_memory.h"
#include "ttm/ttm_module.h"
#include "drm_mm.h"
#include "drm_global.h"
#include "linux/workqueue.h"
#include "linux/fs.h"
#include "linux/spinlock.h"
struct ttm_backend;
struct ttm_backend_func {
/**
* struct ttm_backend_func member populate
*
* @backend: Pointer to a struct ttm_backend.
* @num_pages: Number of pages to populate.
* @pages: Array of pointers to ttm pages.
* @dummy_read_page: Page to be used instead of NULL pages in the
* array @pages.
*
* Populate the backend with ttm pages. Depending on the backend,
* it may or may not copy the @pages array.
*/
int (*populate) (struct ttm_backend *backend,
unsigned long num_pages, struct page **pages,
struct page *dummy_read_page);
/**
* struct ttm_backend_func member clear
*
* @backend: Pointer to a struct ttm_backend.
*
* This is an "unpopulate" function. Release all resources
* allocated with populate.
*/
void (*clear) (struct ttm_backend *backend);
/**
* struct ttm_backend_func member bind
*
* @backend: Pointer to a struct ttm_backend.
* @bo_mem: Pointer to a struct ttm_mem_reg describing the
* memory type and location for binding.
*
* Bind the backend pages into the aperture in the location
* indicated by @bo_mem. This function should be able to handle
* differences between aperture- and system page sizes.
*/
int (*bind) (struct ttm_backend *backend, struct ttm_mem_reg *bo_mem);
/**
* struct ttm_backend_func member unbind
*
* @backend: Pointer to a struct ttm_backend.
*
* Unbind previously bound backend pages. This function should be
* able to handle differences between aperture- and system page sizes.
*/
int (*unbind) (struct ttm_backend *backend);
/**
* struct ttm_backend_func member destroy
*
* @backend: Pointer to a struct ttm_backend.
*
* Destroy the backend.
*/
void (*destroy) (struct ttm_backend *backend);
};
/**
* struct ttm_backend
*
* @bdev: Pointer to a struct ttm_bo_device.
* @flags: For driver use.
* @func: Pointer to a struct ttm_backend_func that describes
* the backend methods.
*
*/
struct ttm_backend {
struct ttm_bo_device *bdev;
uint32_t flags;
struct ttm_backend_func *func;
};
#define TTM_PAGE_FLAG_USER (1 << 1)
#define TTM_PAGE_FLAG_USER_DIRTY (1 << 2)
#define TTM_PAGE_FLAG_WRITE (1 << 3)
#define TTM_PAGE_FLAG_SWAPPED (1 << 4)
#define TTM_PAGE_FLAG_PERSISTANT_SWAP (1 << 5)
#define TTM_PAGE_FLAG_ZERO_ALLOC (1 << 6)
#define TTM_PAGE_FLAG_DMA32 (1 << 7)
enum ttm_caching_state {
tt_uncached,
tt_wc,
tt_cached
};
/**
* struct ttm_tt
*
* @dummy_read_page: Page to map where the ttm_tt page array contains a NULL
* pointer.
* @pages: Array of pages backing the data.
* @first_himem_page: Himem pages are put last in the page array, which
* enables us to run caching attribute changes on only the first part
* of the page array containing lomem pages. This is the index of the
* first himem page.
* @last_lomem_page: Index of the last lomem page in the page array.
* @num_pages: Number of pages in the page array.
* @bdev: Pointer to the current struct ttm_bo_device.
* @be: Pointer to the ttm backend.
* @tsk: The task for user ttm.
* @start: virtual address for user ttm.
* @swap_storage: Pointer to shmem struct file for swap storage.
* @caching_state: The current caching state of the pages.
* @state: The current binding state of the pages.
*
* This is a structure holding the pages, caching- and aperture binding
* status for a buffer object that isn't backed by fixed (VRAM / AGP)
* memory.
*/
struct ttm_tt {
struct page *dummy_read_page;
struct page **pages;
long first_himem_page;
long last_lomem_page;
uint32_t page_flags;
unsigned long num_pages;
struct ttm_bo_global *glob;
struct ttm_backend *be;
struct task_struct *tsk;
unsigned long start;
struct file *swap_storage;
enum ttm_caching_state caching_state;
enum {
tt_bound,
tt_unbound,
tt_unpopulated,
} state;
};
#define TTM_MEMTYPE_FLAG_FIXED (1 << 0) /* Fixed (on-card) PCI memory */
#define TTM_MEMTYPE_FLAG_MAPPABLE (1 << 1) /* Memory mappable */
#define TTM_MEMTYPE_FLAG_CMA (1 << 3) /* Can't map aperture */
/**
* struct ttm_mem_type_manager
*
* @has_type: The memory type has been initialized.
* @use_type: The memory type is enabled.
* @flags: TTM_MEMTYPE_XX flags identifying the traits of the memory
* managed by this memory type.
* @gpu_offset: If used, the GPU offset of the first managed page of
* fixed memory or the first managed location in an aperture.
* @size: Size of the managed region.
* @available_caching: A mask of available caching types, TTM_PL_FLAG_XX,
* as defined in ttm_placement_common.h
* @default_caching: The default caching policy used for a buffer object
* placed in this memory type if the user doesn't provide one.
* @manager: The range manager used for this memory type. FIXME: If the aperture
* has a page size different from the underlying system, the granularity
* of this manager should take care of this. But the range allocating code
* in ttm_bo.c needs to be modified for this.
* @lru: The lru list for this memory type.
*
* This structure is used to identify and manage memory types for a device.
* It's set up by the ttm_bo_driver::init_mem_type method.
*/
struct ttm_mem_type_manager;
struct ttm_mem_type_manager_func {
int (*init)(struct ttm_mem_type_manager *man, unsigned long p_size);
int (*takedown)(struct ttm_mem_type_manager *man);
int (*get_node)(struct ttm_mem_type_manager *man,
struct ttm_buffer_object *bo,
struct ttm_placement *placement,
struct ttm_mem_reg *mem);
void (*put_node)(struct ttm_mem_type_manager *man,
struct ttm_mem_reg *mem);
void (*debug)(struct ttm_mem_type_manager *man, const char *prefix);
};
struct ttm_mem_type_manager {
struct ttm_bo_device *bdev;
/*
* No protection. Constant from start.
*/
bool has_type;
bool use_type;
uint32_t flags;
unsigned long gpu_offset;
uint64_t size;
uint32_t available_caching;
uint32_t default_caching;
/*
* Protected by the bdev->lru_lock.
* TODO: Consider one lru_lock per ttm_mem_type_manager.
* Plays ill with list removal, though.
*/
const struct ttm_mem_type_manager_func *func;
void *priv;
struct list_head lru;
};
/**
* struct ttm_bo_driver
*
* @create_ttm_backend_entry: Callback to create a struct ttm_backend.
* @invalidate_caches: Callback to invalidate read caches when a buffer object
* has been evicted.
* @init_mem_type: Callback to initialize a struct ttm_mem_type_manager
* structure.
* @evict_flags: Callback to obtain placement flags when a buffer is evicted.
* @move: Callback for a driver to hook in accelerated functions to
* move a buffer.
* If set to NULL, a potentially slow memcpy() move is used.
* @sync_obj_signaled: See ttm_fence_api.h
* @sync_obj_wait: See ttm_fence_api.h
* @sync_obj_flush: See ttm_fence_api.h
* @sync_obj_unref: See ttm_fence_api.h
* @sync_obj_ref: See ttm_fence_api.h
*/
struct ttm_bo_driver {
/**
* struct ttm_bo_driver member create_ttm_backend_entry
*
* @bdev: The buffer object device.
*
* Create a driver specific struct ttm_backend.
*/
struct ttm_backend *(*create_ttm_backend_entry)
(struct ttm_bo_device *bdev);
/**
* struct ttm_bo_driver member invalidate_caches
*
* @bdev: the buffer object device.
* @flags: new placement of the rebound buffer object.
*
* A previosly evicted buffer has been rebound in a
* potentially new location. Tell the driver that it might
* consider invalidating read (texture) caches on the next command
* submission as a consequence.
*/
int (*invalidate_caches) (struct ttm_bo_device *bdev, uint32_t flags);
int (*init_mem_type) (struct ttm_bo_device *bdev, uint32_t type,
struct ttm_mem_type_manager *man);
/**
* struct ttm_bo_driver member evict_flags:
*
* @bo: the buffer object to be evicted
*
* Return the bo flags for a buffer which is not mapped to the hardware.
* These will be placed in proposed_flags so that when the move is
* finished, they'll end up in bo->mem.flags
*/
void(*evict_flags) (struct ttm_buffer_object *bo,
struct ttm_placement *placement);
/**
* struct ttm_bo_driver member move:
*
* @bo: the buffer to move
* @evict: whether this motion is evicting the buffer from
* the graphics address space
* @interruptible: Use interruptible sleeps if possible when sleeping.
* @no_wait: whether this should give up and return -EBUSY
* if this move would require sleeping
* @new_mem: the new memory region receiving the buffer
*
* Move a buffer between two memory regions.
*/
int (*move) (struct ttm_buffer_object *bo,
bool evict, bool interruptible,
bool no_wait_reserve, bool no_wait_gpu,
struct ttm_mem_reg *new_mem);
/**
* struct ttm_bo_driver_member verify_access
*
* @bo: Pointer to a buffer object.
* @filp: Pointer to a struct file trying to access the object.
*
* Called from the map / write / read methods to verify that the
* caller is permitted to access the buffer object.
* This member may be set to NULL, which will refuse this kind of
* access for all buffer objects.
* This function should return 0 if access is granted, -EPERM otherwise.
*/
int (*verify_access) (struct ttm_buffer_object *bo,
struct file *filp);
/**
* In case a driver writer dislikes the TTM fence objects,
* the driver writer can replace those with sync objects of
* his / her own. If it turns out that no driver writer is
* using these. I suggest we remove these hooks and plug in
* fences directly. The bo driver needs the following functionality:
* See the corresponding functions in the fence object API
* documentation.
*/
bool (*sync_obj_signaled) (void *sync_obj, void *sync_arg);
int (*sync_obj_wait) (void *sync_obj, void *sync_arg,
bool lazy, bool interruptible);
int (*sync_obj_flush) (void *sync_obj, void *sync_arg);
void (*sync_obj_unref) (void **sync_obj);
void *(*sync_obj_ref) (void *sync_obj);
/* hook to notify driver about a driver move so it
* can do tiling things */
void (*move_notify)(struct ttm_buffer_object *bo,
struct ttm_mem_reg *new_mem);
/* notify the driver we are taking a fault on this BO
* and have reserved it */
int (*fault_reserve_notify)(struct ttm_buffer_object *bo);
/**
* notify the driver that we're about to swap out this bo
*/
void (*swap_notify) (struct ttm_buffer_object *bo);
/**
* Driver callback on when mapping io memory (for bo_move_memcpy
* for instance). TTM will take care to call io_mem_free whenever
* the mapping is not use anymore. io_mem_reserve & io_mem_free
* are balanced.
*/
int (*io_mem_reserve)(struct ttm_bo_device *bdev, struct ttm_mem_reg *mem);
void (*io_mem_free)(struct ttm_bo_device *bdev, struct ttm_mem_reg *mem);
};
/**
* struct ttm_bo_global_ref - Argument to initialize a struct ttm_bo_global.
*/
struct ttm_bo_global_ref {
struct drm_global_reference ref;
struct ttm_mem_global *mem_glob;
};
/**
* struct ttm_bo_global - Buffer object driver global data.
*
* @mem_glob: Pointer to a struct ttm_mem_global object for accounting.
* @dummy_read_page: Pointer to a dummy page used for mapping requests
* of unpopulated pages.
* @shrink: A shrink callback object used for buffer object swap.
* @ttm_bo_extra_size: Extra size (sizeof(struct ttm_buffer_object) excluded)
* used by a buffer object. This is excluding page arrays and backing pages.
* @ttm_bo_size: This is @ttm_bo_extra_size + sizeof(struct ttm_buffer_object).
* @device_list_mutex: Mutex protecting the device list.
* This mutex is held while traversing the device list for pm options.
* @lru_lock: Spinlock protecting the bo subsystem lru lists.
* @device_list: List of buffer object devices.
* @swap_lru: Lru list of buffer objects used for swapping.
*/
struct ttm_bo_global {
/**
* Constant after init.
*/
struct kobject kobj;
struct ttm_mem_global *mem_glob;
struct page *dummy_read_page;
struct ttm_mem_shrink shrink;
size_t ttm_bo_extra_size;
size_t ttm_bo_size;
struct mutex device_list_mutex;
spinlock_t lru_lock;
/**
* Protected by device_list_mutex.
*/
struct list_head device_list;
/**
* Protected by the lru_lock.
*/
struct list_head swap_lru;
/**
* Internal protection.
*/
atomic_t bo_count;
};
#define TTM_NUM_MEM_TYPES 8
#define TTM_BO_PRIV_FLAG_MOVING 0 /* Buffer object is moving and needs
idling before CPU mapping */
#define TTM_BO_PRIV_FLAG_MAX 1
/**
* struct ttm_bo_device - Buffer object driver device-specific data.
*
* @driver: Pointer to a struct ttm_bo_driver struct setup by the driver.
* @man: An array of mem_type_managers.
* @addr_space_mm: Range manager for the device address space.
* lru_lock: Spinlock that protects the buffer+device lru lists and
* ddestroy lists.
* @nice_mode: Try nicely to wait for buffer idle when cleaning a manager.
* If a GPU lockup has been detected, this is forced to 0.
* @dev_mapping: A pointer to the struct address_space representing the
* device address space.
* @wq: Work queue structure for the delayed delete workqueue.
*
*/
struct ttm_bo_device {
/*
* Constant after bo device init / atomic.
*/
struct list_head device_list;
struct ttm_bo_global *glob;
struct ttm_bo_driver *driver;
rwlock_t vm_lock;
struct ttm_mem_type_manager man[TTM_NUM_MEM_TYPES];
/*
* Protected by the vm lock.
*/
struct rb_root addr_space_rb;
struct drm_mm addr_space_mm;
/*
* Protected by the global:lru lock.
*/
struct list_head ddestroy;
/*
* Protected by load / firstopen / lastclose /unload sync.
*/
bool nice_mode;
struct address_space *dev_mapping;
/*
* Internal protection.
*/
struct delayed_work wq;
bool need_dma32;
};
/**
* ttm_flag_masked
*
* @old: Pointer to the result and original value.
* @new: New value of bits.
* @mask: Mask of bits to change.
*
* Convenience function to change a number of bits identified by a mask.
*/
static inline uint32_t
ttm_flag_masked(uint32_t *old, uint32_t new, uint32_t mask)
{
*old ^= (*old ^ new) & mask;
return *old;
}
/**
* ttm_tt_create
*
* @bdev: pointer to a struct ttm_bo_device:
* @size: Size of the data needed backing.
* @page_flags: Page flags as identified by TTM_PAGE_FLAG_XX flags.
* @dummy_read_page: See struct ttm_bo_device.
*
* Create a struct ttm_tt to back data with system memory pages.
* No pages are actually allocated.
* Returns:
* NULL: Out of memory.
*/
extern struct ttm_tt *ttm_tt_create(struct ttm_bo_device *bdev,
unsigned long size,
uint32_t page_flags,
struct page *dummy_read_page);
/**
* ttm_tt_set_user:
*
* @ttm: The struct ttm_tt to populate.
* @tsk: A struct task_struct for which @start is a valid user-space address.
* @start: A valid user-space address.
* @num_pages: Size in pages of the user memory area.
*
* Populate a struct ttm_tt with a user-space memory area after first pinning
* the pages backing it.
* Returns:
* !0: Error.
*/
extern int ttm_tt_set_user(struct ttm_tt *ttm,
struct task_struct *tsk,
unsigned long start, unsigned long num_pages);
/**
* ttm_ttm_bind:
*
* @ttm: The struct ttm_tt containing backing pages.
* @bo_mem: The struct ttm_mem_reg identifying the binding location.
*
* Bind the pages of @ttm to an aperture location identified by @bo_mem
*/
extern int ttm_tt_bind(struct ttm_tt *ttm, struct ttm_mem_reg *bo_mem);
/**
* ttm_tt_populate:
*
* @ttm: The struct ttm_tt to contain the backing pages.
*
* Add backing pages to all of @ttm
*/
extern int ttm_tt_populate(struct ttm_tt *ttm);
/**
* ttm_ttm_destroy:
*
* @ttm: The struct ttm_tt.
*
* Unbind, unpopulate and destroy a struct ttm_tt.
*/
extern void ttm_tt_destroy(struct ttm_tt *ttm);
/**
* ttm_ttm_unbind:
*
* @ttm: The struct ttm_tt.
*
* Unbind a struct ttm_tt.
*/
extern void ttm_tt_unbind(struct ttm_tt *ttm);
/**
* ttm_ttm_destroy:
*
* @ttm: The struct ttm_tt.
* @index: Index of the desired page.
*
* Return a pointer to the struct page backing @ttm at page
* index @index. If the page is unpopulated, one will be allocated to
* populate that index.
*
* Returns:
* NULL on OOM.
*/
extern struct page *ttm_tt_get_page(struct ttm_tt *ttm, int index);
/**
* ttm_tt_cache_flush:
*
* @pages: An array of pointers to struct page:s to flush.
* @num_pages: Number of pages to flush.
*
* Flush the data of the indicated pages from the cpu caches.
* This is used when changing caching attributes of the pages from
* cache-coherent.
*/
extern void ttm_tt_cache_flush(struct page *pages[], unsigned long num_pages);
/**
* ttm_tt_set_placement_caching:
*
* @ttm A struct ttm_tt the backing pages of which will change caching policy.
* @placement: Flag indicating the desired caching policy.
*
* This function will change caching policy of any default kernel mappings of
* the pages backing @ttm. If changing from cached to uncached or
* write-combined,
* all CPU caches will first be flushed to make sure the data of the pages
* hit RAM. This function may be very costly as it involves global TLB
* and cache flushes and potential page splitting / combining.
*/
extern int ttm_tt_set_placement_caching(struct ttm_tt *ttm, uint32_t placement);
extern int ttm_tt_swapout(struct ttm_tt *ttm,
struct file *persistant_swap_storage);
/*
* ttm_bo.c
*/
/**
* ttm_mem_reg_is_pci
*
* @bdev: Pointer to a struct ttm_bo_device.
* @mem: A valid struct ttm_mem_reg.
*
* Returns true if the memory described by @mem is PCI memory,
* false otherwise.
*/
extern bool ttm_mem_reg_is_pci(struct ttm_bo_device *bdev,
struct ttm_mem_reg *mem);
/**
* ttm_bo_mem_space
*
* @bo: Pointer to a struct ttm_buffer_object. the data of which
* we want to allocate space for.
* @proposed_placement: Proposed new placement for the buffer object.
* @mem: A struct ttm_mem_reg.
* @interruptible: Sleep interruptible when sliping.
* @no_wait_reserve: Return immediately if other buffers are busy.
* @no_wait_gpu: Return immediately if the GPU is busy.
*
* Allocate memory space for the buffer object pointed to by @bo, using
* the placement flags in @mem, potentially evicting other idle buffer objects.
* This function may sleep while waiting for space to become available.
* Returns:
* -EBUSY: No space available (only if no_wait == 1).
* -ENOMEM: Could not allocate memory for the buffer object, either due to
* fragmentation or concurrent allocators.
* -ERESTARTSYS: An interruptible sleep was interrupted by a signal.
*/
extern int ttm_bo_mem_space(struct ttm_buffer_object *bo,
struct ttm_placement *placement,
struct ttm_mem_reg *mem,
bool interruptible,
bool no_wait_reserve, bool no_wait_gpu);
extern void ttm_bo_mem_put(struct ttm_buffer_object *bo,
struct ttm_mem_reg *mem);
extern void ttm_bo_mem_put_locked(struct ttm_buffer_object *bo,
struct ttm_mem_reg *mem);
/**
* ttm_bo_wait_for_cpu
*
* @bo: Pointer to a struct ttm_buffer_object.
* @no_wait: Don't sleep while waiting.
*
* Wait until a buffer object is no longer sync'ed for CPU access.
* Returns:
* -EBUSY: Buffer object was sync'ed for CPU access. (only if no_wait == 1).
* -ERESTARTSYS: An interruptible sleep was interrupted by a signal.
*/
extern int ttm_bo_wait_cpu(struct ttm_buffer_object *bo, bool no_wait);
/**
* ttm_bo_pci_offset - Get the PCI offset for the buffer object memory.
*
* @bo Pointer to a struct ttm_buffer_object.
* @bus_base On return the base of the PCI region
* @bus_offset On return the byte offset into the PCI region
* @bus_size On return the byte size of the buffer object or zero if
* the buffer object memory is not accessible through a PCI region.
*
* Returns:
* -EINVAL if the buffer object is currently not mappable.
* 0 otherwise.
*/
extern int ttm_bo_pci_offset(struct ttm_bo_device *bdev,
struct ttm_mem_reg *mem,
unsigned long *bus_base,
unsigned long *bus_offset,
unsigned long *bus_size);
extern int ttm_mem_io_reserve(struct ttm_bo_device *bdev,
struct ttm_mem_reg *mem);
extern void ttm_mem_io_free(struct ttm_bo_device *bdev,
struct ttm_mem_reg *mem);
extern void ttm_bo_global_release(struct drm_global_reference *ref);
extern int ttm_bo_global_init(struct drm_global_reference *ref);
extern int ttm_bo_device_release(struct ttm_bo_device *bdev);
/**
* ttm_bo_device_init
*
* @bdev: A pointer to a struct ttm_bo_device to initialize.
* @mem_global: A pointer to an initialized struct ttm_mem_global.
* @driver: A pointer to a struct ttm_bo_driver set up by the caller.
* @file_page_offset: Offset into the device address space that is available
* for buffer data. This ensures compatibility with other users of the
* address space.
*
* Initializes a struct ttm_bo_device:
* Returns:
* !0: Failure.
*/
extern int ttm_bo_device_init(struct ttm_bo_device *bdev,
struct ttm_bo_global *glob,
struct ttm_bo_driver *driver,
uint64_t file_page_offset, bool need_dma32);
/**
* ttm_bo_unmap_virtual
*
* @bo: tear down the virtual mappings for this BO
*/
extern void ttm_bo_unmap_virtual(struct ttm_buffer_object *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.
* @use_sequence: If @bo is already reserved, Only sleep waiting for
* it to become unreserved if @sequence < (@bo)->sequence.
*
* Locks a buffer object for validation. (Or prevents other processes from
* locking it for validation) and removes it from lru lists, while taking
* a number of measures to prevent deadlocks.
*
* Deadlocks may occur when two processes try to reserve multiple buffers in
* different order, either by will or as a result of a buffer being evicted
* to make room for a buffer already reserved. (Buffers are reserved before
* they are evicted). The following algorithm prevents such deadlocks from
* occuring:
* 1) Buffers are reserved with the lru spinlock held. Upon successful
* reservation they are removed from the lru list. This stops a reserved buffer
* from being evicted. However the lru spinlock is released between the time
* a buffer is selected for eviction and the time it is reserved.
* Therefore a check is made when a buffer is reserved for eviction, that it
* is still the first buffer in the lru list, before it is removed from the
* list. @check_lru == 1 forces this check. If it fails, the function returns
* -EINVAL, and the caller should then choose a new buffer to evict and repeat
* the procedure.
* 2) Processes attempting to reserve multiple buffers other than for eviction,
* (typically execbuf), should first obtain a unique 32-bit
* validation sequence number,
* and call this function with @use_sequence == 1 and @sequence == the unique
* sequence number. If upon call of this function, the buffer object is already
* reserved, the validation sequence is checked against the validation
* sequence of the process currently reserving the buffer,
* and if the current validation sequence is greater than that of the process
* holding the reservation, the function returns -EAGAIN. Otherwise it sleeps
* waiting for the buffer to become unreserved, after which it retries
* reserving.
* The caller should, when receiving an -EAGAIN error
* release all its buffer reservations, wait for @bo to become unreserved, and
* then rerun the validation with the same validation sequence. This procedure
* will always guarantee that the process with the lowest validation sequence
* will eventually succeed, preventing both deadlocks and starvation.
*
* Returns:
* -EAGAIN: The reservation may cause a deadlock.
* Release all buffer reservations, wait for @bo to become unreserved and
* try again. (only if use_sequence == 1).
* -ERESTARTSYS: A wait for the buffer to become unreserved was interrupted by
* a signal. Release all buffer reservations and return to user-space.
*/
extern int ttm_bo_reserve(struct ttm_buffer_object *bo,
bool interruptible,
bool no_wait, bool use_sequence, uint32_t sequence);
/**
* ttm_bo_unreserve
*
* @bo: A pointer to a struct ttm_buffer_object.
*
* Unreserve a previous reservation of @bo.
*/
extern void ttm_bo_unreserve(struct ttm_buffer_object *bo);
/**
* ttm_bo_wait_unreserved
*
* @bo: A pointer to a struct ttm_buffer_object.
*
* Wait for a struct ttm_buffer_object to become unreserved.
* This is typically used in the execbuf code to relax cpu-usage when
* a potential deadlock condition backoff.
*/
extern int ttm_bo_wait_unreserved(struct ttm_buffer_object *bo,
bool interruptible);
/*
* ttm_bo_util.c
*/
/**
* ttm_bo_move_ttm
*
* @bo: A pointer to a struct ttm_buffer_object.
* @evict: 1: This is an eviction. Don't try to pipeline.
* @no_wait_reserve: Return immediately if other buffers are busy.
* @no_wait_gpu: Return immediately if the GPU is busy.
* @new_mem: struct ttm_mem_reg indicating where to move.
*
* Optimized move function for a buffer object with both old and
* new placement backed by a TTM. The function will, if successful,
* free any old aperture space, and set (@new_mem)->mm_node to NULL,
* and update the (@bo)->mem placement flags. If unsuccessful, the old
* data remains untouched, and it's up to the caller to free the
* memory space indicated by @new_mem.
* Returns:
* !0: Failure.
*/
extern int ttm_bo_move_ttm(struct ttm_buffer_object *bo,
bool evict, bool no_wait_reserve,
bool no_wait_gpu, struct ttm_mem_reg *new_mem);
/**
* ttm_bo_move_memcpy
*
* @bo: A pointer to a struct ttm_buffer_object.
* @evict: 1: This is an eviction. Don't try to pipeline.
* @no_wait_reserve: Return immediately if other buffers are busy.
* @no_wait_gpu: Return immediately if the GPU is busy.
* @new_mem: struct ttm_mem_reg indicating where to move.
*
* Fallback move function for a mappable buffer object in mappable memory.
* The function will, if successful,
* free any old aperture space, and set (@new_mem)->mm_node to NULL,
* and update the (@bo)->mem placement flags. If unsuccessful, the old
* data remains untouched, and it's up to the caller to free the
* memory space indicated by @new_mem.
* Returns:
* !0: Failure.
*/
extern int ttm_bo_move_memcpy(struct ttm_buffer_object *bo,
bool evict, bool no_wait_reserve,
bool no_wait_gpu, struct ttm_mem_reg *new_mem);
/**
* ttm_bo_free_old_node
*
* @bo: A pointer to a struct ttm_buffer_object.
*
* Utility function to free an old placement after a successful move.
*/
extern void ttm_bo_free_old_node(struct ttm_buffer_object *bo);
/**
* ttm_bo_move_accel_cleanup.
*
* @bo: A pointer to a struct ttm_buffer_object.
* @sync_obj: A sync object that signals when moving is complete.
* @sync_obj_arg: An argument to pass to the sync object idle / wait
* functions.
* @evict: This is an evict move. Don't return until the buffer is idle.
* @no_wait_reserve: Return immediately if other buffers are busy.
* @no_wait_gpu: Return immediately if the GPU is busy.
* @new_mem: struct ttm_mem_reg indicating where to move.
*
* Accelerated move function to be called when an accelerated move
* has been scheduled. The function will create a new temporary buffer object
* representing the old placement, and put the sync object on both buffer
* objects. After that the newly created buffer object is unref'd to be
* destroyed when the move is complete. This will help pipeline
* buffer moves.
*/
extern int ttm_bo_move_accel_cleanup(struct ttm_buffer_object *bo,
void *sync_obj,
void *sync_obj_arg,
bool evict, bool no_wait_reserve,
bool no_wait_gpu,
struct ttm_mem_reg *new_mem);
/**
* ttm_io_prot
*
* @c_state: Caching state.
* @tmp: Page protection flag for a normal, cached mapping.
*
* Utility function that returns the pgprot_t that should be used for
* setting up a PTE with the caching model indicated by @c_state.
*/
extern pgprot_t ttm_io_prot(uint32_t caching_flags, pgprot_t tmp);
extern const struct ttm_mem_type_manager_func ttm_bo_manager_func;
#if (defined(CONFIG_AGP) || (defined(CONFIG_AGP_MODULE) && defined(MODULE)))
#define TTM_HAS_AGP
#include <linux/agp_backend.h>
/**
* ttm_agp_backend_init
*
* @bdev: Pointer to a struct ttm_bo_device.
* @bridge: The agp bridge this device is sitting on.
*
* Create a TTM backend that uses the indicated AGP bridge as an aperture
* for TT memory. This function uses the linux agpgart interface to
* bind and unbind memory backing a ttm_tt.
*/
extern struct ttm_backend *ttm_agp_backend_init(struct ttm_bo_device *bdev,
struct agp_bridge_data *bridge);
#endif
#endif
