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 biter->__sg_advance = ib_umem_offset(umem) & ~(pgsz - 1);
81 biter->__sg_numblocks = ib_umem_num_dma_blocks(umem, pgsz);
82}
83
84static inline bool __rdma_umem_block_iter_next(struct ib_block_iter *biter)
85{
86 return __rdma_block_iter_next(biter) && biter->__sg_numblocks--;
87}
88
89/**
90 * rdma_umem_for_each_dma_block - iterate over contiguous DMA blocks of the umem
91 * @umem: umem to iterate over
92 * @pgsz: Page size to split the list into
93 *
94 * pgsz must be <= PAGE_SIZE or computed by ib_umem_find_best_pgsz(). The
95 * returned DMA blocks will be aligned to pgsz and span the range:
96 * ALIGN_DOWN(umem->address, pgsz) to ALIGN(umem->address + umem->length, pgsz)
97 *
98 * Performs exactly ib_umem_num_dma_blocks() iterations.
99 */
100#define rdma_umem_for_each_dma_block(umem, biter, pgsz) \
101 for (__rdma_umem_block_iter_start(biter, umem, pgsz); \
102 __rdma_umem_block_iter_next(biter);)
103
104#ifdef CONFIG_INFINIBAND_USER_MEM
105
106struct ib_umem *ib_umem_get(struct ib_device *device, unsigned long addr,
107 size_t size, int access);
108void ib_umem_release(struct ib_umem *umem);
109int ib_umem_copy_from(void *dst, struct ib_umem *umem, size_t offset,
110 size_t length);
111unsigned long ib_umem_find_best_pgsz(struct ib_umem *umem,
112 unsigned long pgsz_bitmap,
113 unsigned long virt);
114
115/**
116 * ib_umem_find_best_pgoff - Find best HW page size
117 *
118 * @umem: umem struct
119 * @pgsz_bitmap bitmap of HW supported page sizes
120 * @pgoff_bitmask: Mask of bits that can be represented with an offset
121 *
122 * This is very similar to ib_umem_find_best_pgsz() except instead of accepting
123 * an IOVA it accepts a bitmask specifying what address bits can be represented
124 * with a page offset.
125 *
126 * For instance if the HW has multiple page sizes, requires 64 byte alignemnt,
127 * and can support aligned offsets up to 4032 then pgoff_bitmask would be
128 * "111111000000".
129 *
130 * If the pgoff_bitmask requires either alignment in the low bit or an
131 * unavailable page size for the high bits, this function returns 0.
132 */
133static inline unsigned long ib_umem_find_best_pgoff(struct ib_umem *umem,
134 unsigned long pgsz_bitmap,
135 u64 pgoff_bitmask)
136{
137 struct scatterlist *sg = umem->sgt_append.sgt.sgl;
138 dma_addr_t dma_addr;
139
140 dma_addr = sg_dma_address(sg) + (umem->address & ~PAGE_MASK);
141 return ib_umem_find_best_pgsz(umem, pgsz_bitmap,
142 virt: dma_addr & pgoff_bitmask);
143}
144
145struct ib_umem_dmabuf *ib_umem_dmabuf_get(struct ib_device *device,
146 unsigned long offset, size_t size,
147 int fd, int access,
148 const struct dma_buf_attach_ops *ops);
149struct ib_umem_dmabuf *ib_umem_dmabuf_get_pinned(struct ib_device *device,
150 unsigned long offset,
151 size_t size, int fd,
152 int access);
153int ib_umem_dmabuf_map_pages(struct ib_umem_dmabuf *umem_dmabuf);
154void ib_umem_dmabuf_unmap_pages(struct ib_umem_dmabuf *umem_dmabuf);
155void ib_umem_dmabuf_release(struct ib_umem_dmabuf *umem_dmabuf);
156
157#else /* CONFIG_INFINIBAND_USER_MEM */
158
159#include <linux/err.h>
160
161static inline struct ib_umem *ib_umem_get(struct ib_device *device,
162 unsigned long addr, size_t size,
163 int access)
164{
165 return ERR_PTR(-EOPNOTSUPP);
166}
167static inline void ib_umem_release(struct ib_umem *umem) { }
168static inline int ib_umem_copy_from(void *dst, struct ib_umem *umem, size_t offset,
169 size_t length) {
170 return -EOPNOTSUPP;
171}
172static inline unsigned long ib_umem_find_best_pgsz(struct ib_umem *umem,
173 unsigned long pgsz_bitmap,
174 unsigned long virt)
175{
176 return 0;
177}
178static inline unsigned long ib_umem_find_best_pgoff(struct ib_umem *umem,
179 unsigned long pgsz_bitmap,
180 u64 pgoff_bitmask)
181{
182 return 0;
183}
184static inline
185struct ib_umem_dmabuf *ib_umem_dmabuf_get(struct ib_device *device,
186 unsigned long offset,
187 size_t size, int fd,
188 int access,
189 struct dma_buf_attach_ops *ops)
190{
191 return ERR_PTR(-EOPNOTSUPP);
192}
193static inline struct ib_umem_dmabuf *
194ib_umem_dmabuf_get_pinned(struct ib_device *device, unsigned long offset,
195 size_t size, int fd, int access)
196{
197 return ERR_PTR(-EOPNOTSUPP);
198}
199static inline int ib_umem_dmabuf_map_pages(struct ib_umem_dmabuf *umem_dmabuf)
200{
201 return -EOPNOTSUPP;
202}
203static inline void ib_umem_dmabuf_unmap_pages(struct ib_umem_dmabuf *umem_dmabuf) { }
204static inline void ib_umem_dmabuf_release(struct ib_umem_dmabuf *umem_dmabuf) { }
205
206#endif /* CONFIG_INFINIBAND_USER_MEM */
207#endif /* IB_UMEM_H */
208

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