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 sg_append_table sgt_append;
29};
30
31struct ib_umem_dmabuf {
32 struct ib_umem umem;
33 struct dma_buf_attachment *attach;
34 struct sg_table *sgt;
35 struct scatterlist *first_sg;
36 struct scatterlist *last_sg;
37 unsigned long first_sg_offset;
38 unsigned long last_sg_trim;
39 void *private;
40 u8 pinned : 1;
41};
42
43static inline struct ib_umem_dmabuf *to_ib_umem_dmabuf(struct ib_umem *umem)
44{
45 return container_of(umem, struct ib_umem_dmabuf, umem);
46}
47
48/* Returns the offset of the umem start relative to the first page. */
49static inline int ib_umem_offset(struct ib_umem *umem)
50{
51 return umem->address & ~PAGE_MASK;
52}
53
54static inline unsigned long ib_umem_dma_offset(struct ib_umem *umem,
55 unsigned long pgsz)
56{
57 return (sg_dma_address(umem->sgt_append.sgt.sgl) + ib_umem_offset(umem)) &
58 (pgsz - 1);
59}
60
61static inline size_t ib_umem_num_dma_blocks(struct ib_umem *umem,
62 unsigned long pgsz)
63{
64 return (size_t)((ALIGN(umem->iova + umem->length, pgsz) -
65 ALIGN_DOWN(umem->iova, pgsz))) /
66 pgsz;
67}
68
69static inline size_t ib_umem_num_pages(struct ib_umem *umem)
70{
71 return ib_umem_num_dma_blocks(umem, PAGE_SIZE);
72}
73
74static inline void __rdma_umem_block_iter_start(struct ib_block_iter *biter,
75 struct ib_umem *umem,
76 unsigned long pgsz)
77{
78 __rdma_block_iter_start(biter, sglist: umem->sgt_append.sgt.sgl,
79 nents: umem->sgt_append.sgt.nents, pgsz);
80}
81
82/**
83 * rdma_umem_for_each_dma_block - iterate over contiguous DMA blocks of the umem
84 * @umem: umem to iterate over
85 * @pgsz: Page size to split the list into
86 *
87 * pgsz must be <= PAGE_SIZE or computed by ib_umem_find_best_pgsz(). The
88 * returned DMA blocks will be aligned to pgsz and span the range:
89 * ALIGN_DOWN(umem->address, pgsz) to ALIGN(umem->address + umem->length, pgsz)
90 *
91 * Performs exactly ib_umem_num_dma_blocks() iterations.
92 */
93#define rdma_umem_for_each_dma_block(umem, biter, pgsz) \
94 for (__rdma_umem_block_iter_start(biter, umem, pgsz); \
95 __rdma_block_iter_next(biter);)
96
97#ifdef CONFIG_INFINIBAND_USER_MEM
98
99struct ib_umem *ib_umem_get(struct ib_device *device, unsigned long addr,
100 size_t size, int access);
101void ib_umem_release(struct ib_umem *umem);
102int ib_umem_copy_from(void *dst, struct ib_umem *umem, size_t offset,
103 size_t length);
104unsigned long ib_umem_find_best_pgsz(struct ib_umem *umem,
105 unsigned long pgsz_bitmap,
106 unsigned long virt);
107
108/**
109 * ib_umem_find_best_pgoff - Find best HW page size
110 *
111 * @umem: umem struct
112 * @pgsz_bitmap bitmap of HW supported page sizes
113 * @pgoff_bitmask: Mask of bits that can be represented with an offset
114 *
115 * This is very similar to ib_umem_find_best_pgsz() except instead of accepting
116 * an IOVA it accepts a bitmask specifying what address bits can be represented
117 * with a page offset.
118 *
119 * For instance if the HW has multiple page sizes, requires 64 byte alignemnt,
120 * and can support aligned offsets up to 4032 then pgoff_bitmask would be
121 * "111111000000".
122 *
123 * If the pgoff_bitmask requires either alignment in the low bit or an
124 * unavailable page size for the high bits, this function returns 0.
125 */
126static inline unsigned long ib_umem_find_best_pgoff(struct ib_umem *umem,
127 unsigned long pgsz_bitmap,
128 u64 pgoff_bitmask)
129{
130 struct scatterlist *sg = umem->sgt_append.sgt.sgl;
131 dma_addr_t dma_addr;
132
133 dma_addr = sg_dma_address(sg) + (umem->address & ~PAGE_MASK);
134 return ib_umem_find_best_pgsz(umem, pgsz_bitmap,
135 virt: dma_addr & pgoff_bitmask);
136}
137
138struct ib_umem_dmabuf *ib_umem_dmabuf_get(struct ib_device *device,
139 unsigned long offset, size_t size,
140 int fd, int access,
141 const struct dma_buf_attach_ops *ops);
142struct ib_umem_dmabuf *ib_umem_dmabuf_get_pinned(struct ib_device *device,
143 unsigned long offset,
144 size_t size, int fd,
145 int access);
146int ib_umem_dmabuf_map_pages(struct ib_umem_dmabuf *umem_dmabuf);
147void ib_umem_dmabuf_unmap_pages(struct ib_umem_dmabuf *umem_dmabuf);
148void ib_umem_dmabuf_release(struct ib_umem_dmabuf *umem_dmabuf);
149
150#else /* CONFIG_INFINIBAND_USER_MEM */
151
152#include <linux/err.h>
153
154static inline struct ib_umem *ib_umem_get(struct ib_device *device,
155 unsigned long addr, size_t size,
156 int access)
157{
158 return ERR_PTR(-EOPNOTSUPP);
159}
160static inline void ib_umem_release(struct ib_umem *umem) { }
161static inline int ib_umem_copy_from(void *dst, struct ib_umem *umem, size_t offset,
162 size_t length) {
163 return -EOPNOTSUPP;
164}
165static inline unsigned long ib_umem_find_best_pgsz(struct ib_umem *umem,
166 unsigned long pgsz_bitmap,
167 unsigned long virt)
168{
169 return 0;
170}
171static inline unsigned long ib_umem_find_best_pgoff(struct ib_umem *umem,
172 unsigned long pgsz_bitmap,
173 u64 pgoff_bitmask)
174{
175 return 0;
176}
177static inline
178struct ib_umem_dmabuf *ib_umem_dmabuf_get(struct ib_device *device,
179 unsigned long offset,
180 size_t size, int fd,
181 int access,
182 struct dma_buf_attach_ops *ops)
183{
184 return ERR_PTR(-EOPNOTSUPP);
185}
186static inline struct ib_umem_dmabuf *
187ib_umem_dmabuf_get_pinned(struct ib_device *device, unsigned long offset,
188 size_t size, int fd, int access)
189{
190 return ERR_PTR(-EOPNOTSUPP);
191}
192static inline int ib_umem_dmabuf_map_pages(struct ib_umem_dmabuf *umem_dmabuf)
193{
194 return -EOPNOTSUPP;
195}
196static inline void ib_umem_dmabuf_unmap_pages(struct ib_umem_dmabuf *umem_dmabuf) { }
197static inline void ib_umem_dmabuf_release(struct ib_umem_dmabuf *umem_dmabuf) { }
198
199#endif /* CONFIG_INFINIBAND_USER_MEM */
200#endif /* IB_UMEM_H */
201

source code of linux/include/rdma/ib_umem.h