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Diffstat (limited to 'include/drm/ttm/ttm_bo_api.h')
| -rw-r--r-- | include/drm/ttm/ttm_bo_api.h | 767 |
1 files changed, 767 insertions, 0 deletions
diff --git a/include/drm/ttm/ttm_bo_api.h b/include/drm/ttm/ttm_bo_api.h new file mode 100644 index 000000000..a01ba2032 --- /dev/null +++ b/include/drm/ttm/ttm_bo_api.h @@ -0,0 +1,767 @@ +/************************************************************************** + * + * 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_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/reservation.h> + +struct ttm_bo_global; + +struct ttm_bo_device; + +struct drm_mm_node; + +struct ttm_placement; + +struct ttm_place; + +/** + * 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 + * + * @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 + * @vma_node: Address space manager node. + * @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 { + /** + * 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; + + struct drm_vma_offset_node vma_node; + + 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 reservation_object *resv; + struct reservation_object ttm_resv; + 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 reservation_object *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_reference - reference a struct ttm_buffer_object + * + * @bo: The buffer object. + * + * Returns a refcounted pointer to a buffer object. + * + * This function is deprecated. Use @ttm_bo_get instead. + */ + +static inline struct ttm_buffer_object * +ttm_bo_reference(struct ttm_buffer_object *bo) +{ + ttm_bo_get(bo); + 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 ttm_bo_put(struct ttm_buffer_object *bo); + +/** + * ttm_bo_unref + * + * @bo: The buffer object. + * + * Unreference and clear a pointer to a buffer object. + * + * This function is deprecated. Use @ttm_bo_put instead. + */ +void ttm_bo_unref(struct ttm_buffer_object **bo); + +/** + * ttm_bo_add_to_lru + * + * @bo: The buffer object. + * + * Add this bo to the relevant mem type lru and, if it's backed by + * system pages (ttms) to the swap list. + * This function must be called with struct ttm_bo_global::lru_lock held, and + * is typically called immediately prior to unreserving a bo. + */ +void ttm_bo_add_to_lru(struct ttm_buffer_object *bo); + +/** + * ttm_bo_del_from_lru + * + * @bo: The buffer object. + * + * Remove this bo from all lru lists used to lookup and reserve an object. + * This function must be called with struct ttm_bo_global::lru_lock held, + * and is usually called just immediately after the bo has been reserved to + * avoid recursive reservation from lru lists. + */ +void ttm_bo_del_from_lru(struct ttm_buffer_object *bo); + +/** + * ttm_bo_move_to_lru_tail + * + * @bo: The buffer object. + * + * 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_bo_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); + +/** + * 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_bo_device *bdev); + +/** + * ttm_bo_unlock_delayed_workqueue + * + * Allows the delayed workqueue to run. + */ +void ttm_bo_unlock_delayed_workqueue(struct ttm_bo_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_synccpu_write_grab + * + * @bo: The buffer object: + * @no_wait: Return immediately if buffer is busy. + * + * Synchronizes a buffer object for CPU RW access. This means + * command submission that affects the buffer will return -EBUSY + * until ttm_bo_synccpu_write_release is called. + * + * Returns + * -EBUSY if the buffer is busy and no_wait is true. + * -ERESTARTSYS if interrupted by a signal. + */ +int ttm_bo_synccpu_write_grab(struct ttm_buffer_object *bo, bool no_wait); + +/** + * ttm_bo_synccpu_write_release: + * + * @bo : The buffer object. + * + * Releases a synccpu lock. + */ +void ttm_bo_synccpu_write_release(struct ttm_buffer_object *bo); + +/** + * ttm_bo_acc_size + * + * @bdev: Pointer to a ttm_bo_device struct. + * @bo_size: size of the buffer object in byte. + * @struct_size: size of the structure holding buffer object datas + * + * Returns size to account for a buffer object + */ +size_t ttm_bo_acc_size(struct ttm_bo_device *bdev, + unsigned long bo_size, + unsigned struct_size); +size_t ttm_bo_dma_acc_size(struct ttm_bo_device *bdev, + unsigned long bo_size, + unsigned struct_size); + +/** + * ttm_bo_init_reserved + * + * @bdev: Pointer to a ttm_bo_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. + * @acc_size: Accounted size for this object. + * @resv: Pointer to a reservation_object, 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_bo_device *bdev, + struct ttm_buffer_object *bo, + unsigned long size, + enum ttm_bo_type type, + struct ttm_placement *placement, + uint32_t page_alignment, + struct ttm_operation_ctx *ctx, + size_t acc_size, + struct sg_table *sg, + struct reservation_object *resv, + void (*destroy) (struct ttm_buffer_object *)); + +/** + * ttm_bo_init + * + * @bdev: Pointer to a ttm_bo_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. + * @acc_size: Accounted size for this object. + * @resv: Pointer to a reservation_object, 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_bo_device *bdev, struct ttm_buffer_object *bo, + unsigned long size, enum ttm_bo_type type, + struct ttm_placement *placement, + uint32_t page_alignment, bool interrubtible, size_t acc_size, + struct sg_table *sg, struct reservation_object *resv, + void (*destroy) (struct ttm_buffer_object *)); + +/** + * ttm_bo_create + * + * @bdev: Pointer to a ttm_bo_device struct. + * @size: Requested size of buffer object. + * @type: Requested type of buffer object. + * @placement: Initial placement. + * @page_alignment: Data alignment in pages. + * @interruptible: If needing to sleep while waiting for GPU resources, + * sleep interruptible. + * @p_bo: On successful completion *p_bo points to the created object. + * + * This function allocates a ttm_buffer_object, and then calls ttm_bo_init + * on that object. The destroy function is set to kfree(). + * Returns + * -ENOMEM: Out of memory. + * -EINVAL: Invalid placement flags. + * -ERESTARTSYS: Interrupted by signal while waiting for resources. + */ +int ttm_bo_create(struct ttm_bo_device *bdev, unsigned long size, + enum ttm_bo_type type, struct ttm_placement *placement, + uint32_t page_alignment, bool interruptible, + struct ttm_buffer_object **p_bo); + +/** + * ttm_bo_init_mm + * + * @bdev: Pointer to a ttm_bo_device struct. + * @mem_type: The memory type. + * @p_size: size managed area in pages. + * + * Initialize a manager for a given memory type. + * Note: if part of driver firstopen, it must be protected from a + * potentially racing lastclose. + * Returns: + * -EINVAL: invalid size or memory type. + * -ENOMEM: Not enough memory. + * May also return driver-specified errors. + */ +int ttm_bo_init_mm(struct ttm_bo_device *bdev, unsigned type, + unsigned long p_size); + +/** + * ttm_bo_clean_mm + * + * @bdev: Pointer to a ttm_bo_device struct. + * @mem_type: The memory type. + * + * Take down a manager for a given memory type after first walking + * the LRU list to evict any buffers left alive. + * + * Normally, this function is part of lastclose() or unload(), and at that + * point there shouldn't be any buffers left created by user-space, since + * there should've been removed by the file descriptor release() method. + * However, before this function is run, make sure to signal all sync objects, + * and verify that the delayed delete queue is empty. The driver must also + * make sure that there are no NO_EVICT buffers present in this memory type + * when the call is made. + * + * If this function is part of a VT switch, the caller must make sure that + * there are no appications currently validating buffers before this + * function is called. The caller can do that by first taking the + * struct ttm_bo_device::ttm_lock in write mode. + * + * Returns: + * -EINVAL: invalid or uninitialized memory type. + * -EBUSY: There are still buffers left in this memory type. + */ +int ttm_bo_clean_mm(struct ttm_bo_device *bdev, unsigned mem_type); + +/** + * ttm_bo_evict_mm + * + * @bdev: Pointer to a ttm_bo_device struct. + * @mem_type: The memory type. + * + * Evicts all buffers on the lru list of the memory type. + * This is normally part of a VT switch or an + * out-of-memory-space-due-to-fragmentation handler. + * The caller must make sure that there are no other processes + * currently validating buffers, and can do that by taking the + * struct ttm_bo_device::ttm_lock in write mode. + * + * Returns: + * -EINVAL: Invalid or uninitialized memory type. + * -ERESTARTSYS: The call was interrupted by a signal while waiting to + * evict a buffer. + */ +int ttm_bo_evict_mm(struct ttm_bo_device *bdev, unsigned mem_type); + +/** + * 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_fbdev_mmap - mmap fbdev memory backed by a ttm buffer object. + * + * @vma: vma as input from the fbdev mmap method. + * @bo: The bo backing the address space. The address space will + * have the same size as the bo, and start at offset 0. + * + * This function is intended to be called by the fbdev mmap method + * if the fbdev address space is to be backed by a bo. + */ +int ttm_fbdev_mmap(struct vm_area_struct *vma, struct ttm_buffer_object *bo); + +/** + * ttm_bo_mmap - mmap out of the ttm device address space. + * + * @filp: filp as input from the mmap method. + * @vma: vma as input from the mmap method. + * @bdev: Pointer to the ttm_bo_device with the address space manager. + * + * This function is intended to be called by the device mmap method. + * if the device address space is to be backed by the bo manager. + */ +int ttm_bo_mmap(struct file *filp, struct vm_area_struct *vma, + struct ttm_bo_device *bdev); + +void *ttm_kmap_atomic_prot(struct page *page, pgprot_t prot); + +void ttm_kunmap_atomic_prot(void *addr, pgprot_t prot); + +/** + * ttm_bo_io + * + * @bdev: Pointer to the struct ttm_bo_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_bo_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_bo_global *glob, + struct ttm_operation_ctx *ctx); +void ttm_bo_swapout_all(struct ttm_bo_device *bdev); +int ttm_bo_wait_unreserved(struct ttm_buffer_object *bo); +#endif |