ib_umem.h revision 331769 
1/*
2 * Copyright (c) 2007 Cisco Systems.  All rights reserved.
3 *
4 * This software is available to you under a choice of one of two
5 * licenses.  You may choose to be licensed under the terms of the GNU
6 * General Public License (GPL) Version 2, available from the file
7 * COPYING in the main directory of this source tree, or the
8 * OpenIB.org BSD license below:
9 *
10 *     Redistribution and use in source and binary forms, with or
11 *     without modification, are permitted provided that the following
12 *     conditions are met:
13 *
14 *      - Redistributions of source code must retain the above
15 *        copyright notice, this list of conditions and the following
16 *        disclaimer.
17 *
18 *      - Redistributions in binary form must reproduce the above
19 *        copyright notice, this list of conditions and the following
20 *        disclaimer in the documentation and/or other materials
21 *        provided with the distribution.
22 *
23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30 * SOFTWARE.
31 */
32
33#ifndef IB_UMEM_H
34#define IB_UMEM_H
35
36#include <linux/list.h>
37#include <linux/scatterlist.h>
38#include <linux/workqueue.h>
39
40struct ib_ucontext;
41struct ib_umem_odp;
42
43struct ib_umem {
44	struct ib_ucontext     *context;
45	size_t			length;
46	unsigned long		address;
47	int			page_size;
48	int                     writable;
49	struct work_struct	work;
50	pid_t			pid;
51	struct mm_struct       *mm;
52	unsigned long		diff;
53	struct ib_umem_odp     *odp_data;
54	struct sg_table sg_head;
55	int             nmap;
56	int             npages;
57};
58
59/* Returns the offset of the umem start relative to the first page. */
60static inline int ib_umem_offset(struct ib_umem *umem)
61{
62	return umem->address & ((unsigned long)umem->page_size - 1);
63}
64
65/* Returns the first page of an ODP umem. */
66static inline unsigned long ib_umem_start(struct ib_umem *umem)
67{
68	return umem->address - ib_umem_offset(umem);
69}
70
71/* Returns the address of the page after the last one of an ODP umem. */
72static inline unsigned long ib_umem_end(struct ib_umem *umem)
73{
74	return PAGE_ALIGN(umem->address + umem->length);
75}
76
77static inline size_t ib_umem_num_pages(struct ib_umem *umem)
78{
79	return (ib_umem_end(umem) - ib_umem_start(umem)) >> PAGE_SHIFT;
80}
81
82#ifdef CONFIG_INFINIBAND_USER_MEM
83
84struct ib_umem *ib_umem_get(struct ib_ucontext *context, unsigned long addr,
85			    size_t size, int access, int dmasync);
86void ib_umem_release(struct ib_umem *umem);
87int ib_umem_page_count(struct ib_umem *umem);
88int ib_umem_copy_from(void *dst, struct ib_umem *umem, size_t offset,
89		      size_t length);
90
91#else /* CONFIG_INFINIBAND_USER_MEM */
92
93#include <linux/err.h>
94
95static inline struct ib_umem *ib_umem_get(struct ib_ucontext *context,
96					  unsigned long addr, size_t size,
97					  int access, int dmasync) {
98	return ERR_PTR(-EINVAL);
99}
100static inline void ib_umem_release(struct ib_umem *umem) { }
101static inline int ib_umem_page_count(struct ib_umem *umem) { return 0; }
102static inline int ib_umem_copy_from(void *dst, struct ib_umem *umem, size_t offset,
103		      		    size_t length) {
104	return -EINVAL;
105}
106#endif /* CONFIG_INFINIBAND_USER_MEM */
107
108#endif /* IB_UMEM_H */
109