1  /* SPDX-License-Identifier: MIT */
2  /*
3   * Copyright © 2021 Intel Corporation
4   */
5  #ifndef __TTM_KMAP_ITER_H__
6  #define __TTM_KMAP_ITER_H__
7  
8  #include <linux/types.h>
9  
10  struct ttm_kmap_iter;
11  struct iosys_map;
12  
13  /**
14   * struct ttm_kmap_iter_ops - Ops structure for a struct
15   * ttm_kmap_iter.
16   * @maps_tt: Whether the iterator maps TT memory directly, as opposed
17   * mapping a TT through an aperture. Both these modes have
18   * struct ttm_resource_manager::use_tt set, but the latter typically
19   * returns is_iomem == true from ttm_mem_io_reserve.
20   */
21  struct ttm_kmap_iter_ops {
22  	/**
23  	 * @map_local: Map a PAGE_SIZE part of the resource using
24  	 * kmap_local semantics.
25  	 * @res_iter: Pointer to the struct ttm_kmap_iter representing
26  	 * the resource.
27  	 * @dmap: The struct iosys_map holding the virtual address after
28  	 * the operation.
29  	 * @i: The location within the resource to map. PAGE_SIZE granularity.
30  	 */
31  	void (*map_local)(struct ttm_kmap_iter *res_iter,
32  			  struct iosys_map *dmap, pgoff_t i);
33  	/**
34  	 * @unmap_local: Unmap a PAGE_SIZE part of the resource previously
35  	 * mapped using kmap_local.
36  	 * @res_iter: Pointer to the struct ttm_kmap_iter representing
37  	 * the resource.
38  	 * @dmap: The struct iosys_map holding the virtual address after
39  	 * the operation.
40  	 */
41  	void (*unmap_local)(struct ttm_kmap_iter *res_iter,
42  			    struct iosys_map *dmap);
43  	bool maps_tt;
44  };
45  
46  /**
47   * struct ttm_kmap_iter - Iterator for kmap_local type operations on a
48   * resource.
49   * @ops: Pointer to the operations struct.
50   *
51   * This struct is intended to be embedded in a resource-specific specialization
52   * implementing operations for the resource.
53   *
54   * Nothing stops us from extending the operations to vmap, vmap_pfn etc,
55   * replacing some or parts of the ttm_bo_util. cpu-map functionality.
56   */
57  struct ttm_kmap_iter {
58  	const struct ttm_kmap_iter_ops *ops;
59  };
60  
61  #endif /* __TTM_KMAP_ITER_H__ */
62