xref: /openbmc/linux/include/rdma/ib_umem.h (revision d0e22329)
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 
40 struct ib_ucontext;
41 struct ib_umem_odp;
42 
43 struct ib_umem {
44 	struct ib_ucontext     *context;
45 	struct mm_struct       *owning_mm;
46 	size_t			length;
47 	unsigned long		address;
48 	int			page_shift;
49 	u32 writable : 1;
50 	u32 hugetlb : 1;
51 	u32 is_odp : 1;
52 	struct work_struct	work;
53 	struct sg_table sg_head;
54 	int             nmap;
55 	int             npages;
56 };
57 
58 /* Returns the offset of the umem start relative to the first page. */
59 static inline int ib_umem_offset(struct ib_umem *umem)
60 {
61 	return umem->address & (BIT(umem->page_shift) - 1);
62 }
63 
64 /* Returns the first page of an ODP umem. */
65 static inline unsigned long ib_umem_start(struct ib_umem *umem)
66 {
67 	return umem->address - ib_umem_offset(umem);
68 }
69 
70 /* Returns the address of the page after the last one of an ODP umem. */
71 static inline unsigned long ib_umem_end(struct ib_umem *umem)
72 {
73 	return ALIGN(umem->address + umem->length, BIT(umem->page_shift));
74 }
75 
76 static inline size_t ib_umem_num_pages(struct ib_umem *umem)
77 {
78 	return (ib_umem_end(umem) - ib_umem_start(umem)) >> umem->page_shift;
79 }
80 
81 #ifdef CONFIG_INFINIBAND_USER_MEM
82 
83 struct ib_umem *ib_umem_get(struct ib_ucontext *context, unsigned long addr,
84 			    size_t size, int access, int dmasync);
85 void ib_umem_release(struct ib_umem *umem);
86 int ib_umem_page_count(struct ib_umem *umem);
87 int ib_umem_copy_from(void *dst, struct ib_umem *umem, size_t offset,
88 		      size_t length);
89 
90 #else /* CONFIG_INFINIBAND_USER_MEM */
91 
92 #include <linux/err.h>
93 
94 static inline struct ib_umem *ib_umem_get(struct ib_ucontext *context,
95 					  unsigned long addr, size_t size,
96 					  int access, int dmasync) {
97 	return ERR_PTR(-EINVAL);
98 }
99 static inline void ib_umem_release(struct ib_umem *umem) { }
100 static inline int ib_umem_page_count(struct ib_umem *umem) { return 0; }
101 static inline int ib_umem_copy_from(void *dst, struct ib_umem *umem, size_t offset,
102 		      		    size_t length) {
103 	return -EINVAL;
104 }
105 #endif /* CONFIG_INFINIBAND_USER_MEM */
106 
107 #endif /* IB_UMEM_H */
108