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1/* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
2/*
3 * Copyright (c) 2007 Cisco Systems. All rights reserved.
4 * Copyright (c) 2020 Intel Corporation. All rights reserved.
5 */
6
7#ifndef IB_UMEM_H
8#define IB_UMEM_H
9
10#include <linux/list.h>
11#include <linux/scatterlist.h>
12#include <linux/workqueue.h>
13#include <rdma/ib_verbs.h>
14
15struct ib_ucontext;
16struct ib_umem_odp;
17struct dma_buf_attach_ops;
18
19struct ib_umem {
20 struct ib_device *ibdev;
21 struct mm_struct *owning_mm;
22 u64 iova;
23 size_t length;
24 unsigned long address;
25 u32 writable : 1;
26 u32 is_odp : 1;
27 u32 is_dmabuf : 1;
28 struct work_struct work;
29 struct sg_table sg_head;
30 int nmap;
31 unsigned int sg_nents;
32};
33
34struct ib_umem_dmabuf {
35 struct ib_umem umem;
36 struct dma_buf_attachment *attach;
37 struct sg_table *sgt;
38 struct scatterlist *first_sg;
39 struct scatterlist *last_sg;
40 unsigned long first_sg_offset;
41 unsigned long last_sg_trim;
42 void *private;
43};
44
45static inline struct ib_umem_dmabuf *to_ib_umem_dmabuf(struct ib_umem *umem)
46{
47 return container_of(umem, struct ib_umem_dmabuf, umem);
48}
49
50/* Returns the offset of the umem start relative to the first page. */
51static inline int ib_umem_offset(struct ib_umem *umem)
52{
53 return umem->address & ~PAGE_MASK;
54}
55
56static inline unsigned long ib_umem_dma_offset(struct ib_umem *umem,
57 unsigned long pgsz)
58{
59 return (sg_dma_address(umem->sg_head.sgl) + ib_umem_offset(umem)) &
60 (pgsz - 1);
61}
62
63static inline size_t ib_umem_num_dma_blocks(struct ib_umem *umem,
64 unsigned long pgsz)
65{
66 return (size_t)((ALIGN(umem->iova + umem->length, pgsz) -
67 ALIGN_DOWN(umem->iova, pgsz))) /
68 pgsz;
69}
70
71static inline size_t ib_umem_num_pages(struct ib_umem *umem)
72{
73 return ib_umem_num_dma_blocks(umem, PAGE_SIZE);
74}
75
76static inline void __rdma_umem_block_iter_start(struct ib_block_iter *biter,
77 struct ib_umem *umem,
78 unsigned long pgsz)
79{
80 __rdma_block_iter_start(biter, umem->sg_head.sgl, umem->nmap, pgsz);
81}
82
83/**
84 * rdma_umem_for_each_dma_block - iterate over contiguous DMA blocks of the umem
85 * @umem: umem to iterate over
86 * @pgsz: Page size to split the list into
87 *
88 * pgsz must be <= PAGE_SIZE or computed by ib_umem_find_best_pgsz(). The
89 * returned DMA blocks will be aligned to pgsz and span the range:
90 * ALIGN_DOWN(umem->address, pgsz) to ALIGN(umem->address + umem->length, pgsz)
91 *
92 * Performs exactly ib_umem_num_dma_blocks() iterations.
93 */
94#define rdma_umem_for_each_dma_block(umem, biter, pgsz) \
95 for (__rdma_umem_block_iter_start(biter, umem, pgsz); \
96 __rdma_block_iter_next(biter);)
97
98#ifdef CONFIG_INFINIBAND_USER_MEM
99
100struct ib_umem *ib_umem_get(struct ib_device *device, unsigned long addr,
101 size_t size, int access);
102void ib_umem_release(struct ib_umem *umem);
103int ib_umem_copy_from(void *dst, struct ib_umem *umem, size_t offset,
104 size_t length);
105unsigned long ib_umem_find_best_pgsz(struct ib_umem *umem,
106 unsigned long pgsz_bitmap,
107 unsigned long virt);
108
109/**
110 * ib_umem_find_best_pgoff - Find best HW page size
111 *
112 * @umem: umem struct
113 * @pgsz_bitmap bitmap of HW supported page sizes
114 * @pgoff_bitmask: Mask of bits that can be represented with an offset
115 *
116 * This is very similar to ib_umem_find_best_pgsz() except instead of accepting
117 * an IOVA it accepts a bitmask specifying what address bits can be represented
118 * with a page offset.
119 *
120 * For instance if the HW has multiple page sizes, requires 64 byte alignemnt,
121 * and can support aligned offsets up to 4032 then pgoff_bitmask would be
122 * "111111000000".
123 *
124 * If the pgoff_bitmask requires either alignment in the low bit or an
125 * unavailable page size for the high bits, this function returns 0.
126 */
127static inline unsigned long ib_umem_find_best_pgoff(struct ib_umem *umem,
128 unsigned long pgsz_bitmap,
129 u64 pgoff_bitmask)
130{
131 struct scatterlist *sg = umem->sg_head.sgl;
132 dma_addr_t dma_addr;
133
134 dma_addr = sg_dma_address(sg) + (umem->address & ~PAGE_MASK);
135 return ib_umem_find_best_pgsz(umem, pgsz_bitmap,
136 dma_addr & pgoff_bitmask);
137}
138
139struct ib_umem_dmabuf *ib_umem_dmabuf_get(struct ib_device *device,
140 unsigned long offset, size_t size,
141 int fd, int access,
142 const struct dma_buf_attach_ops *ops);
143int ib_umem_dmabuf_map_pages(struct ib_umem_dmabuf *umem_dmabuf);
144void ib_umem_dmabuf_unmap_pages(struct ib_umem_dmabuf *umem_dmabuf);
145void ib_umem_dmabuf_release(struct ib_umem_dmabuf *umem_dmabuf);
146
147#else /* CONFIG_INFINIBAND_USER_MEM */
148
149#include <linux/err.h>
150
151static inline struct ib_umem *ib_umem_get(struct ib_device *device,
152 unsigned long addr, size_t size,
153 int access)
154{
155 return ERR_PTR(-EOPNOTSUPP);
156}
157static inline void ib_umem_release(struct ib_umem *umem) { }
158static inline int ib_umem_copy_from(void *dst, struct ib_umem *umem, size_t offset,
159 size_t length) {
160 return -EOPNOTSUPP;
161}
162static inline unsigned long ib_umem_find_best_pgsz(struct ib_umem *umem,
163 unsigned long pgsz_bitmap,
164 unsigned long virt)
165{
166 return 0;
167}
168static inline unsigned long ib_umem_find_best_pgoff(struct ib_umem *umem,
169 unsigned long pgsz_bitmap,
170 u64 pgoff_bitmask)
171{
172 return 0;
173}
174static inline
175struct ib_umem_dmabuf *ib_umem_dmabuf_get(struct ib_device *device,
176 unsigned long offset,
177 size_t size, int fd,
178 int access,
179 struct dma_buf_attach_ops *ops)
180{
181 return ERR_PTR(-EOPNOTSUPP);
182}
183static inline int ib_umem_dmabuf_map_pages(struct ib_umem_dmabuf *umem_dmabuf)
184{
185 return -EOPNOTSUPP;
186}
187static inline void ib_umem_dmabuf_unmap_pages(struct ib_umem_dmabuf *umem_dmabuf) { }
188static inline void ib_umem_dmabuf_release(struct ib_umem_dmabuf *umem_dmabuf) { }
189
190#endif /* CONFIG_INFINIBAND_USER_MEM */
191#endif /* IB_UMEM_H */