/************************************************************************** * * 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_device; struct drm_mm_node; /** * struct ttm_place * * @fpfn: first valid page frame number to put the object * @lpfn: last valid page frame number to put the object * @flags: memory domain and caching flags for the object * * Structure indicating a possible place to put an object. */ struct ttm_place { unsigned fpfn; unsigned lpfn; uint32_t flags; }; /** * struct ttm_placement * * @num_placement: number of preferred placements * @placement: preferred placements * @num_busy_placement: number of preferred placements when need to evict buffer * @busy_placement: preferred placements when need to evict buffer * * Structure indicating the placement you request for an object. */ struct ttm_placement { unsigned num_placement; const struct ttm_place *placement; unsigned num_busy_placement; const struct ttm_place *busy_placement; }; /** * 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; unsigned long 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. * @priv_flags: Flags describing buffer object internal state. * @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_global *glob; 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. */ unsigned long priv_flags; struct drm_vma_offset_node vma_node; /** * 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 */ uint32_t cur_placement; 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; }; /** * ttm_bo_reference - reference a struct ttm_buffer_object * * @bo: The buffer object. * * Returns a refcounted pointer to a buffer object. */ static inline struct ttm_buffer_object * ttm_bo_reference(struct ttm_buffer_object *bo) { kref_get(&bo->kref); 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. */ extern int ttm_bo_wait(struct ttm_buffer_object *bo, bool lazy, bool interruptible, bool no_wait); /** * ttm_bo_validate * * @bo: The buffer object. * @placement: Proposed placement for the buffer object. * @interruptible: Sleep interruptible if sleeping. * @no_wait_gpu: Return immediately if the GPU is busy. * * 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. */ extern int ttm_bo_validate(struct ttm_buffer_object *bo, struct ttm_placement *placement, bool interruptible, bool no_wait_gpu); /** * ttm_bo_unref * * @bo: The buffer object. * * Unreference and clear a pointer to a buffer object. */ extern void ttm_bo_unref(struct ttm_buffer_object **bo); /** * ttm_bo_list_ref_sub * * @bo: The buffer object. * @count: The number of references with which to decrease @bo::list_kref; * @never_free: The refcount should not reach zero with this operation. * * Release @count lru list references to this buffer object. */ extern void ttm_bo_list_ref_sub(struct ttm_buffer_object *bo, int count, bool never_free); /** * 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. */ extern 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. */ extern int ttm_bo_del_from_lru(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 */ extern int ttm_bo_lock_delayed_workqueue(struct ttm_bo_device *bdev); /** * ttm_bo_unlock_delayed_workqueue * * Allows the delayed workqueue to run. */ extern void ttm_bo_unlock_delayed_workqueue(struct ttm_bo_device *bdev, int resched); /** * 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. */ extern 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. */ extern 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 * * @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. * @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. 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 object kref and list_kref are set to 1. * 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. */ extern 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, struct file *persistent_swap_storage, 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. * @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. Typically, this would * point to the shmem object backing a GEM object if TTM is used to back a * GEM user interface. * @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. */ extern 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 file *persistent_swap_storage, 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. */ extern 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. */ extern 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. */ extern 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. */ extern 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. */ extern 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. */ extern 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. */ extern int ttm_bo_mmap(struct file *filp, struct vm_area_struct *vma, struct ttm_bo_device *bdev); /** * 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. */ extern 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); extern void ttm_bo_swapout_all(struct ttm_bo_device *bdev); extern int ttm_bo_wait_unreserved(struct ttm_buffer_object *bo); #endif