wrapper/page_alloc.h

   1 #ifndef _LTTNG_WRAPPER_PAGE_ALLOC_H
   2 #define _LTTNG_WRAPPER_PAGE_ALLOC_H
   3
   4 /*
   5  * wrapper/page_alloc.h
   6  *
   7  * wrapper around get_pfnblock_flags_mask. Using KALLSYMS to get its address
   8  * when available, else we need to have a kernel that exports this function to
   9  * GPL modules.
  10  *
  11  * Copyright (C) 2015 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
  12  *
  13  * This library is free software; you can redistribute it and/or
  14  * modify it under the terms of the GNU Lesser General Public
  15  * License as published by the Free Software Foundation; only
  16  * version 2.1 of the License.
  17  *
  18  * This library is distributed in the hope that it will be useful,
  19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  21  * Lesser General Public License for more details.
  22  *
  23  * You should have received a copy of the GNU Lesser General Public
  24  * License along with this library; if not, write to the Free Software
  25  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  26  */
  27
  28 #include "../lttng-kernel-version.h"
  29
  30 /*
  31  * We need to redefine get_pfnblock_flags_mask to our wrapper, because
  32  * the get_pageblock_migratetype() macro uses it.
  33  */
  34 #if defined(CONFIG_KALLSYMS) && (LINUX_VERSION_CODE >= KERNEL_VERSION(3,19,2))
  35
  36 #define get_pfnblock_flags_mask         wrapper_get_pfnblock_flags_mask
  37
  38 #include <linux/mm_types.h>
  39
  40 int wrapper_get_pfnblock_flags_mask_init(void);
  41
  42 #else
  43
  44 #include <linux/mm_types.h>
  45
  46 static inline
  47 int wrapper_get_pfnblock_flags_mask_init(void)
  48 {
  49         return 0;
  50 }
  51
  52 #endif
  53
  54 /*
  55  * For a specific range of Ubuntu 3.13 kernels, we need to redefine
  56  * get_pageblock_flags_mask to our wrapper, because the
  57  * get_pageblock_migratetype() macro uses it. This function has been
  58  * introduced into mainline within commit
  59  * e58469bafd0524e848c3733bc3918d854595e20f, but never actually showed
  60  * up in a stable kernel version, since it has been changed by commit
  61  * dc4b0caff24d9b2918e9f27bc65499ee63187eba. Since Ubuntu chose to only
  62  * backport the former commit but not the latter, we need to do a
  63  * special case to cover this.
  64  */
  65 #if (defined(CONFIG_KALLSYMS) \
  66         && LTTNG_UBUNTU_KERNEL_RANGE(3,13,11,50, 3,14,0,0))
  67
  68 #define get_pageblock_flags_mask        wrapper_get_pageblock_flags_mask
  69
  70 #include <linux/mm_types.h>
  71
  72 int wrapper_get_pageblock_flags_mask_init(void);
  73
  74 #else
  75
  76 #include <linux/mm_types.h>
  77
  78 static inline
  79 int wrapper_get_pageblock_flags_mask_init(void)
  80 {
  81         return 0;
  82 }
  83
  84 #endif
  85
  86 #endif /* _LTTNG_WRAPPER_PAGE_ALLOC_H */