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
  39 struct ib_ucontext;
  40
  41 struct ib_umem {
  42         struct ib_ucontext     *context;
  43         size_t                  length;
  44         int                     offset;
  45         int                     page_size;
  46         int                     writable;
  47         struct list_head        chunk_list;
  48 };
  49
  50 struct ib_umem_chunk {
  51         struct list_head        list;
  52         int                     nents;
  53         int                     nmap;
  54         struct scatterlist      page_list[0];
  55 };
  56
  57 #ifdef CONFIG_INFINIBAND_USER_MEM
  58
  59 struct ib_umem *ib_umem_get(struct ib_ucontext *context, unsigned long addr,
  60                             size_t size, int access);
  61 void ib_umem_release(struct ib_umem *umem);
  62 int ib_umem_page_count(struct ib_umem *umem);
  63
  64 #else /* CONFIG_INFINIBAND_USER_MEM */
  65
  66 #include <linux/err.h>
  67
  68 static inline struct ib_umem *ib_umem_get(struct ib_ucontext *context,
  69                                           unsigned long addr, size_t size,
  70                                           int access) {
  71         return ERR_PTR(-EINVAL);
  72 }
  73 static inline void ib_umem_release(struct ib_umem *umem) { }
  74 static inline int ib_umem_page_count(struct ib_umem *umem) { return 0; }
  75
  76 #endif /* CONFIG_INFINIBAND_USER_MEM */
  77
  78 #endif /* IB_UMEM_H */