wrapper/page_alloc.h

   1 /* SPDX-License-Identifier: (GPL-2.0 or LGPL-2.1)
   2  *
   3  * wrapper/page_alloc.h
   4  *
   5  * wrapper around get_pfnblock_flags_mask. Using KALLSYMS to get its address
   6  * when available, else we need to have a kernel that exports this function to
   7  * GPL modules.
   8  *
   9  * Copyright (C) 2015 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
  10  */
  11
  12 #ifndef _LTTNG_WRAPPER_PAGE_ALLOC_H
  13 #define _LTTNG_WRAPPER_PAGE_ALLOC_H
  14
  15 #include <lttng-kernel-version.h>
  16
  17 /*
  18  * We need to redefine get_pfnblock_flags_mask to our wrapper, because
  19  * the get_pageblock_migratetype() macro uses it.
  20  */
  21 #if (defined(CONFIG_KALLSYMS) \
  22         && (LINUX_VERSION_CODE >= KERNEL_VERSION(3,19,2)        \
  23                 || LTTNG_KERNEL_RANGE(3,14,36, 3,15,0)          \
  24                 || LTTNG_KERNEL_RANGE(3,18,10, 3,19,0)          \
  25                 || LTTNG_DEBIAN_KERNEL_RANGE(3,16,7,9,0,0, 3,17,0,0,0,0) \
  26                 || LTTNG_UBUNTU_KERNEL_RANGE(3,16,7,34, 3,17,0,0)))
  27
  28 #define get_pfnblock_flags_mask         wrapper_get_pfnblock_flags_mask
  29
  30 #include <linux/mm_types.h>
  31
  32 int wrapper_get_pfnblock_flags_mask_init(void);
  33
  34 #else
  35
  36 #include <linux/mm_types.h>
  37
  38 static inline
  39 int wrapper_get_pfnblock_flags_mask_init(void)
  40 {
  41         return 0;
  42 }
  43
  44 #endif
  45
  46 /*
  47  * For a specific range of Ubuntu 3.13 kernels, we need to redefine
  48  * get_pageblock_flags_mask to our wrapper, because the
  49  * get_pageblock_migratetype() macro uses it. This function has been
  50  * introduced into mainline within commit
  51  * e58469bafd0524e848c3733bc3918d854595e20f, but never actually showed
  52  * up in a stable kernel version, since it has been changed by commit
  53  * dc4b0caff24d9b2918e9f27bc65499ee63187eba. Since Ubuntu chose to only
  54  * backport the former commit but not the latter, we need to do a
  55  * special case to cover this.
  56  */
  57 #if (defined(CONFIG_KALLSYMS) \
  58         && LTTNG_UBUNTU_KERNEL_RANGE(3,13,11,50, 3,14,0,0))
  59
  60 #define get_pageblock_flags_mask        wrapper_get_pageblock_flags_mask
  61
  62 #include <linux/mm_types.h>
  63
  64 int wrapper_get_pageblock_flags_mask_init(void);
  65
  66 #else
  67
  68 #include <linux/mm_types.h>
  69
  70 static inline
  71 int wrapper_get_pageblock_flags_mask_init(void)
  72 {
  73         return 0;
  74 }
  75
  76 #endif
  77
  78 #endif /* _LTTNG_WRAPPER_PAGE_ALLOC_H */