include/rdma/ib_umem.h

   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         size_t                  length;
  46         unsigned long           address;
  47         int                     page_shift;
  48         int                     writable;
  49         int                     hugetlb;
  50         struct work_struct      work;
  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. */
  60 static inline int ib_umem_offset(struct ib_umem *umem)
  61 {
  62         return umem->address & (BIT(umem->page_shift) - 1);
  63 }
  64
  65 /* Returns the first page of an ODP umem. */
  66 static 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. */
  72 static inline unsigned long ib_umem_end(struct ib_umem *umem)
  73 {
  74         return ALIGN(umem->address + umem->length, BIT(umem->page_shift));
  75 }
  76
  77 static inline size_t ib_umem_num_pages(struct ib_umem *umem)
  78 {
  79         return (ib_umem_end(umem) - ib_umem_start(umem)) >> umem->page_shift;
  80 }
  81
  82 #ifdef CONFIG_INFINIBAND_USER_MEM
  83
  84 struct ib_umem *ib_umem_get(struct ib_ucontext *context, unsigned long addr,
  85                             size_t size, int access, int dmasync);
  86 void ib_umem_release(struct ib_umem *umem);
  87 int ib_umem_page_count(struct ib_umem *umem);
  88 int 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
  95 static 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 }
 100 static inline void ib_umem_release(struct ib_umem *umem) { }
 101 static inline int ib_umem_page_count(struct ib_umem *umem) { return 0; }
 102 static 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 */