1 /* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only)
4 * wrapper around get_pfnblock_flags_mask and Ubuntu
5 * get_pageblock_flags_mask. Using KALLSYMS to get their address when
6 * available, else we need to have a kernel that exports this function
9 * Copyright (C) 2015 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
12 #ifdef CONFIG_KALLSYMS
14 #include <linux/kallsyms.h>
15 #include <linux/mm_types.h>
16 #include <linux/module.h>
17 #include <wrapper/kallsyms.h>
18 #include <wrapper/page_alloc.h>
21 unsigned long (*get_pfnblock_flags_mask_sym
)(struct page
*page
,
23 unsigned long end_bitidx
,
26 unsigned long wrapper_get_pfnblock_flags_mask(struct page
*page
,
28 unsigned long end_bitidx
,
31 WARN_ON_ONCE(!get_pfnblock_flags_mask_sym
);
32 if (get_pfnblock_flags_mask_sym
) {
33 struct irq_ibt_state irq_ibt_state
;
36 irq_ibt_state
= wrapper_irq_ibt_save();
37 ret
= get_pfnblock_flags_mask_sym(page
, pfn
, end_bitidx
, mask
);
38 wrapper_irq_ibt_restore(irq_ibt_state
);
44 EXPORT_SYMBOL_GPL(wrapper_get_pfnblock_flags_mask
);
46 int wrapper_get_pfnblock_flags_mask_init(void)
48 get_pfnblock_flags_mask_sym
=
49 (void *) kallsyms_lookup_funcptr("get_pfnblock_flags_mask");
50 if (!get_pfnblock_flags_mask_sym
)
54 EXPORT_SYMBOL_GPL(wrapper_get_pfnblock_flags_mask_init
);
57 * Canary function to check for 'get_pfnblock_flags_mask()' at compile time.
59 * From 'include/linux/pageblock-flags.h':
61 * unsigned long get_pfnblock_flags_mask(struct page *page,
63 * unsigned long end_bitidx,
64 * unsigned long mask);
66 __attribute__((unused
)) static
67 unsigned long __canary__get_pfnblock_flags_mask(struct page
*page
,
69 unsigned long end_bitidx
,
72 return get_pfnblock_flags_mask(page
, pfn
, end_bitidx
, mask
);
77 #include <linux/pageblock-flags.h>