[lttng-modules.git] / src / wrapper / page_alloc.c

/* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only)
 * wrapper/page_alloc.c
 *
 * wrapper around get_pfnblock_flags_mask and Ubuntu
 * get_pageblock_flags_mask. Using KALLSYMS to get their address when
 * available, else we need to have a kernel that exports this function
 * to GPL modules.
 *
 * Copyright (C) 2015 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 */

#include <lttng/kernel-version.h>

#if (defined(CONFIG_KALLSYMS) \
	&& (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(3,19,2)	\
		|| LTTNG_KERNEL_RANGE(3,14,36, 3,15,0)		\
		|| LTTNG_KERNEL_RANGE(3,18,10, 3,19,0)		\
		|| LTTNG_DEBIAN_KERNEL_RANGE(3,16,7,9,0,0, 3,17,0,0,0,0) \
		|| LTTNG_UBUNTU_KERNEL_RANGE(3,16,7,34, 3,17,0,0)))

#include <linux/kallsyms.h>
#include <linux/mm_types.h>
#include <linux/module.h>
#include <wrapper/kallsyms.h>
#include <wrapper/page_alloc.h>

static
unsigned long (*get_pfnblock_flags_mask_sym)(struct page *page,
		unsigned long pfn,
		unsigned long end_bitidx,
		unsigned long mask);

unsigned long wrapper_get_pfnblock_flags_mask(struct page *page,
		unsigned long pfn,
		unsigned long end_bitidx,
		unsigned long mask)
{
	WARN_ON_ONCE(!get_pfnblock_flags_mask_sym);
	if (get_pfnblock_flags_mask_sym) {
		struct irq_ibt_state irq_ibt_state;
		unsigned long ret;

		irq_ibt_state = wrapper_irq_ibt_save();
		ret = get_pfnblock_flags_mask_sym(page, pfn, end_bitidx, mask);
		wrapper_irq_ibt_restore(irq_ibt_state);
		return ret;
	} else {
		return -ENOSYS;
	}
}
EXPORT_SYMBOL_GPL(wrapper_get_pfnblock_flags_mask);

int wrapper_get_pfnblock_flags_mask_init(void)
{
	get_pfnblock_flags_mask_sym =
		(void *) kallsyms_lookup_funcptr("get_pfnblock_flags_mask");
	if (!get_pfnblock_flags_mask_sym)
		return -1;
	return 0;
}
EXPORT_SYMBOL_GPL(wrapper_get_pfnblock_flags_mask_init);

/*
 * Canary function to check for 'get_pfnblock_flags_mask()' at compile time.
 *
 * From 'include/linux/pageblock-flags.h':
 *
 *   unsigned long get_pfnblock_flags_mask(struct page *page,
 *                                         unsigned long pfn,
 *                                         unsigned long end_bitidx,
 *                                         unsigned long mask);
 */
__attribute__((unused)) static
unsigned long __canary__get_pfnblock_flags_mask(struct page *page,
						unsigned long pfn,
						unsigned long end_bitidx,
						unsigned long mask)
{
	return get_pfnblock_flags_mask(page, pfn, end_bitidx, mask);
}

#else

#include <linux/pageblock-flags.h>

#endif

#if (defined(CONFIG_KALLSYMS) \
	&& LTTNG_UBUNTU_KERNEL_RANGE(3,13,11,50, 3,14,0,0))

#include <linux/kallsyms.h>
#include <linux/mm_types.h>
#include <linux/module.h>
#include <wrapper/kallsyms.h>
#include <wrapper/page_alloc.h>

static
unsigned long (*get_pageblock_flags_mask_sym)(struct page *page,
		unsigned long end_bitidx,
		unsigned long mask);

unsigned long wrapper_get_pageblock_flags_mask(struct page *page,
		unsigned long end_bitidx,
		unsigned long mask)
{
	WARN_ON_ONCE(!get_pageblock_flags_mask_sym);
	if (get_pageblock_flags_mask_sym) {
		return get_pageblock_flags_mask_sym(page, end_bitidx, mask);
	} else {
		return -ENOSYS;
	}
}
EXPORT_SYMBOL_GPL(wrapper_get_pageblock_flags_mask);

int wrapper_get_pageblock_flags_mask_init(void)
{
	get_pageblock_flags_mask_sym =
		(void *) kallsyms_lookup_funcptr("get_pageblock_flags_mask");
	if (!get_pageblock_flags_mask_sym)
		return -1;
	return 0;
}
EXPORT_SYMBOL_GPL(wrapper_get_pfnblock_flags_mask_init);

#else

#include <linux/pageblock-flags.h>

#endif
Commit	Line	Data
b7cdc182	1	/* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only)
389d7070 MD	2	* wrapper/page_alloc.c
389d7070 MD	3	*
0e14d6e7 MD	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
	7	* to GPL modules.
389d7070 MD	8	*
389d7070 MD	9	* Copyright (C) 2015 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
389d7070 MD	10	*/
389d7070 MD	11
2df37e95	12	#include <lttng/kernel-version.h>
389d7070	13
ffc696db	14	#if (defined(CONFIG_KALLSYMS) \
5f4c791e	15	&& (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(3,19,2) \
36561775 MD	16	\|\| LTTNG_KERNEL_RANGE(3,14,36, 3,15,0) \
36561775 MD	17	\|\| LTTNG_KERNEL_RANGE(3,18,10, 3,19,0) \
397c12b4 MD	18	\|\| LTTNG_DEBIAN_KERNEL_RANGE(3,16,7,9,0,0, 3,17,0,0,0,0) \
397c12b4 MD	19	\|\| LTTNG_UBUNTU_KERNEL_RANGE(3,16,7,34, 3,17,0,0)))
389d7070 MD	20
	21	#include <linux/kallsyms.h>
	22	#include <linux/mm_types.h>
	23	#include <linux/module.h>
5a2f5e92 MD	24	#include <wrapper/kallsyms.h>
5a2f5e92 MD	25	#include <wrapper/page_alloc.h>
389d7070 MD	26
	27	static
	28	unsigned long (get_pfnblock_flags_mask_sym)(struct page page,
	29	unsigned long pfn,
	30	unsigned long end_bitidx,
	31	unsigned long mask);
	32
	33	unsigned long wrapper_get_pfnblock_flags_mask(struct page *page,
	34	unsigned long pfn,
	35	unsigned long end_bitidx,
	36	unsigned long mask)
	37	{
	38	WARN_ON_ONCE(!get_pfnblock_flags_mask_sym);
	39	if (get_pfnblock_flags_mask_sym) {
41cbf575 MD	40	struct irq_ibt_state irq_ibt_state;
	41	unsigned long ret;
	42
	43	irq_ibt_state = wrapper_irq_ibt_save();
	44	ret = get_pfnblock_flags_mask_sym(page, pfn, end_bitidx, mask);
	45	wrapper_irq_ibt_restore(irq_ibt_state);
	46	return ret;
389d7070 MD	47	} else {
	48	return -ENOSYS;
	49	}
	50	}
	51	EXPORT_SYMBOL_GPL(wrapper_get_pfnblock_flags_mask);
	52
	53	int wrapper_get_pfnblock_flags_mask_init(void)
	54	{
	55	get_pfnblock_flags_mask_sym =
	56	(void *) kallsyms_lookup_funcptr("get_pfnblock_flags_mask");
	57	if (!get_pfnblock_flags_mask_sym)
	58	return -1;
	59	return 0;
	60	}
1c999280	61	EXPORT_SYMBOL_GPL(wrapper_get_pfnblock_flags_mask_init);
389d7070	62
3dfec228 MJ	63	/*
	64	* Canary function to check for 'get_pfnblock_flags_mask()' at compile time.
	65	*
	66	* From 'include/linux/pageblock-flags.h':
	67	*
	68	* unsigned long get_pfnblock_flags_mask(struct page *page,
	69	* unsigned long pfn,
	70	* unsigned long end_bitidx,
	71	* unsigned long mask);
	72	*/
	73	__attribute__((unused)) static
	74	unsigned long __canary__get_pfnblock_flags_mask(struct page *page,
	75	unsigned long pfn,
	76	unsigned long end_bitidx,
	77	unsigned long mask)
	78	{
	79	return get_pfnblock_flags_mask(page, pfn, end_bitidx, mask);
	80	}
	81
0e14d6e7	82	#else
389d7070 MD	83
	84	#include <linux/pageblock-flags.h>
	85
0e14d6e7 MD	86	#endif
	87
	88	#if (defined(CONFIG_KALLSYMS) \
	89	&& LTTNG_UBUNTU_KERNEL_RANGE(3,13,11,50, 3,14,0,0))
	90
	91	#include <linux/kallsyms.h>
	92	#include <linux/mm_types.h>
	93	#include <linux/module.h>
5a2f5e92 MD	94	#include <wrapper/kallsyms.h>
5a2f5e92 MD	95	#include <wrapper/page_alloc.h>
0e14d6e7 MD	96
	97	static
	98	unsigned long (get_pageblock_flags_mask_sym)(struct page page,
	99	unsigned long end_bitidx,
	100	unsigned long mask);
	101
	102	unsigned long wrapper_get_pageblock_flags_mask(struct page *page,
	103	unsigned long end_bitidx,
	104	unsigned long mask)
	105	{
	106	WARN_ON_ONCE(!get_pageblock_flags_mask_sym);
	107	if (get_pageblock_flags_mask_sym) {
	108	return get_pageblock_flags_mask_sym(page, end_bitidx, mask);
	109	} else {
	110	return -ENOSYS;
	111	}
	112	}
	113	EXPORT_SYMBOL_GPL(wrapper_get_pageblock_flags_mask);
	114
	115	int wrapper_get_pageblock_flags_mask_init(void)
	116	{
	117	get_pageblock_flags_mask_sym =
	118	(void *) kallsyms_lookup_funcptr("get_pageblock_flags_mask");
	119	if (!get_pageblock_flags_mask_sym)
	120	return -1;
	121	return 0;
	122	}
1c999280	123	EXPORT_SYMBOL_GPL(wrapper_get_pfnblock_flags_mask_init);
0e14d6e7 MD	124
	125	#else
	126
	127	#include <linux/pageblock-flags.h>
	128
	129	#endif