xref: /linux/include/rdma/ib_umem.h (revision 52338415)
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 #include <rdma/ib_verbs.h>
40 
41 struct ib_ucontext;
42 struct ib_umem_odp;
43 
44 struct ib_umem {
45 	struct ib_device       *ibdev;
46 	struct mm_struct       *owning_mm;
47 	size_t			length;
48 	unsigned long		address;
49 	u32 writable : 1;
50 	u32 is_odp : 1;
51 	struct work_struct	work;
52 	struct sg_table sg_head;
53 	int             nmap;
54 	unsigned int    sg_nents;
55 };
56 
57 /* Returns the offset of the umem start relative to the first page. */
58 static inline int ib_umem_offset(struct ib_umem *umem)
59 {
60 	return umem->address & ~PAGE_MASK;
61 }
62 
63 static inline size_t ib_umem_num_pages(struct ib_umem *umem)
64 {
65 	return (ALIGN(umem->address + umem->length, PAGE_SIZE) -
66 		ALIGN_DOWN(umem->address, PAGE_SIZE)) >>
67 	       PAGE_SHIFT;
68 }
69 
70 #ifdef CONFIG_INFINIBAND_USER_MEM
71 
72 struct ib_umem *ib_umem_get(struct ib_udata *udata, unsigned long addr,
73 			    size_t size, int access, int dmasync);
74 void ib_umem_release(struct ib_umem *umem);
75 int ib_umem_page_count(struct ib_umem *umem);
76 int ib_umem_copy_from(void *dst, struct ib_umem *umem, size_t offset,
77 		      size_t length);
78 unsigned long ib_umem_find_best_pgsz(struct ib_umem *umem,
79 				     unsigned long pgsz_bitmap,
80 				     unsigned long virt);
81 
82 #else /* CONFIG_INFINIBAND_USER_MEM */
83 
84 #include <linux/err.h>
85 
86 static inline struct ib_umem *ib_umem_get(struct ib_udata *udata,
87 					  unsigned long addr, size_t size,
88 					  int access, int dmasync)
89 {
90 	return ERR_PTR(-EINVAL);
91 }
92 static inline void ib_umem_release(struct ib_umem *umem) { }
93 static inline int ib_umem_page_count(struct ib_umem *umem) { return 0; }
94 static inline int ib_umem_copy_from(void *dst, struct ib_umem *umem, size_t offset,
95 		      		    size_t length) {
96 	return -EINVAL;
97 }
98 static inline int ib_umem_find_best_pgsz(struct ib_umem *umem,
99 					 unsigned long pgsz_bitmap,
100 					 unsigned long virt) {
101 	return -EINVAL;
102 }
103 
104 #endif /* CONFIG_INFINIBAND_USER_MEM */
105 
106 #endif /* IB_UMEM_H */
107