[lttng-modules.git] / include / wrapper / vmalloc.h

/* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only)
 *
 * wrapper/vmalloc.h
 *
 * wrapper around vmalloc_sync_all. Using KALLSYMS to get its address when
 * available, else we need to have a kernel that exports this function to GPL
 * modules.
 *
 * Copyright (C) 2011-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 */

#ifndef _LTTNG_WRAPPER_VMALLOC_H
#define _LTTNG_WRAPPER_VMALLOC_H

#include <linux/version.h>
#include <linux/vmalloc.h>
#include <linux/mm.h>

#ifdef CONFIG_KALLSYMS

#include <linux/kallsyms.h>
#include <wrapper/kallsyms.h>
#include <lttng/kernel-version.h>

#if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,6,0) \
  || LTTNG_KERNEL_RANGE(5,5,12, 5,6,0)            \
  || LTTNG_KERNEL_RANGE(5,4,28, 5,5,0)            \
  || LTTNG_KERNEL_RANGE(5,2,37, 5,3,0)            \
  || LTTNG_KERNEL_RANGE(4,19,113, 4,20,0)         \
  || LTTNG_KERNEL_RANGE(4,14,175, 4,15,0)         \
  || LTTNG_KERNEL_RANGE(4,9,218, 4,10,0)          \
  || LTTNG_KERNEL_RANGE(4,4,218, 4,5,0))	  \
  || LTTNG_UBUNTU_KERNEL_RANGE(4,15,18,97, 4,16,0,0) \
  || LTTNG_UBUNTU_KERNEL_RANGE(5,0,21,48, 5,1,0,0)   \
  || LTTNG_UBUNTU_KERNEL_RANGE(5,3,18,52, 5,4,0,0)

static inline
void wrapper_vmalloc_sync_mappings(void)
{
	void (*vmalloc_sync_mappings_sym)(void);

	vmalloc_sync_mappings_sym = (void *) kallsyms_lookup_funcptr("vmalloc_sync_mappings");
	if (vmalloc_sync_mappings_sym) {
		vmalloc_sync_mappings_sym();
	} else {
#ifdef CONFIG_X86
		/*
		 * Only x86 needs vmalloc_sync_mappings to make sure LTTng does not
		 * trigger recursive page faults.
		 */
		printk_once(KERN_WARNING "LTTng: vmalloc_sync_mappings symbol lookup failed.\n");
		printk_once(KERN_WARNING "Page fault handler and NMI tracing might trigger faults.\n");
#endif
	}
}

#else /* #if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,6,0)) */

/*
 * Map vmalloc_sync_mappings to vmalloc_sync_all() on kernels before 5.7.
 */
static inline
void wrapper_vmalloc_sync_mappings(void)
{
	void (*vmalloc_sync_all_sym)(void);

	vmalloc_sync_all_sym = (void *) kallsyms_lookup_funcptr("vmalloc_sync_all");
	if (vmalloc_sync_all_sym) {
		vmalloc_sync_all_sym();
	} else {
#ifdef CONFIG_X86
		/*
		 * Only x86 needs vmalloc_sync_all to make sure LTTng does not
		 * trigger recursive page faults.
		 */
		printk_once(KERN_WARNING "LTTng: vmalloc_sync_all symbol lookup failed.\n");
		printk_once(KERN_WARNING "Page fault handler and NMI tracing might trigger faults.\n");
#endif
	}
}

#endif /* #else #if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,6,0)) */

#else

#if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,6,0) \
  || LTTNG_KERNEL_RANGE(5,5,12, 5,6,0)            \
  || LTTNG_KERNEL_RANGE(5,4,28, 5,5,0)            \
  || LTTNG_KERNEL_RANGE(5,2,37, 5,3,0)            \
  || LTTNG_KERNEL_RANGE(4,19,113, 4,20,0)         \
  || LTTNG_KERNEL_RANGE(4,14,175, 4,15,0)         \
  || LTTNG_KERNEL_RANGE(4,9,218, 4,10,0)          \
  || LTTNG_KERNEL_RANGE(4,4,218, 4,5,0))	  \
  || LTTNG_UBUNTU_KERNEL_RANGE(4,15,18,97, 4,18,0,0) \
  || LTTNG_UBUNTU_KERNEL_RANGE(5,0,21,48, 5,1,0,0)   \
  || LTTNG_UBUNTU_KERNEL_RANGE(5,3,18,52, 5,4,0,0)

static inline
void wrapper_vmalloc_sync_mappings(void)
{
	return vmalloc_sync_mappings();
}

#else /* #if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,6,0)) */

static inline
void wrapper_vmalloc_sync_mappings(void)
{
	return vmalloc_sync_all();
}

#endif /* #else #if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,6,0)) */

#endif

#if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,12,0))
static inline
void *lttng_kvmalloc_node(unsigned long size, gfp_t flags, int node)
{
	void *ret;

	ret = kvmalloc_node(size, flags, node);
	if (is_vmalloc_addr(ret)) {
		/*
		 * Make sure we don't trigger recursive page faults in the
		 * tracing fast path.
		 */
		wrapper_vmalloc_sync_mappings();
	}
	return ret;
}

static inline
void *lttng_kvzalloc_node(unsigned long size, gfp_t flags, int node)
{
	return lttng_kvmalloc_node(size, flags | __GFP_ZERO, node);
}

static inline
void *lttng_kvmalloc(unsigned long size, gfp_t flags)
{
	return lttng_kvmalloc_node(size, flags, NUMA_NO_NODE);
}

static inline
void *lttng_kvzalloc(unsigned long size, gfp_t flags)
{
	return lttng_kvzalloc_node(size, flags, NUMA_NO_NODE);
}

static inline
void lttng_kvfree(const void *addr)
{
	kvfree(addr);
}

#else

#include <linux/slab.h>

static inline
void print_vmalloc_node_range_warning(void)
{
	printk_once(KERN_WARNING "LTTng: __vmalloc_node_range symbol lookup failed.\n");
	printk_once(KERN_WARNING "Tracer performance will be degraded on NUMA systems.\n");
	printk_once(KERN_WARNING "Please rebuild your kernel with CONFIG_KALLSYMS enabled.\n");
}

/*
 * kallsyms wrapper of __vmalloc_node with a fallback to kmalloc_node.
 */
static inline
void *__lttng_vmalloc_node_range(unsigned long size, unsigned long align,
			unsigned long start, unsigned long end, gfp_t gfp_mask,
			pgprot_t prot, unsigned long vm_flags, int node,
			const void *caller)
{
#ifdef CONFIG_KALLSYMS
	/*
	 * If we have KALLSYMS, get * __vmalloc_node_range which is not exported.
	 */
	void *(*lttng__vmalloc_node_range)(unsigned long size, unsigned long align,
			unsigned long start, unsigned long end, gfp_t gfp_mask,
			pgprot_t prot, unsigned long vm_flags, int node,
			const void *caller);

	lttng__vmalloc_node_range = (void *) kallsyms_lookup_funcptr("__vmalloc_node_range");
	if (lttng__vmalloc_node_range)
		return lttng__vmalloc_node_range(size, align, start, end, gfp_mask, prot,
				vm_flags, node, caller);
#endif
	if (node != NUMA_NO_NODE)
		print_vmalloc_node_range_warning();
	return __vmalloc(size, gfp_mask, prot);
}

/**
 * lttng_kvmalloc_node - attempt to allocate physically contiguous memory, but upon
 * failure, fall back to non-contiguous (vmalloc) allocation.
 * @size: size of the request.
 * @flags: gfp mask for the allocation - must be compatible with GFP_KERNEL.
 *
 * Uses kmalloc to get the memory but if the allocation fails then falls back
 * to the vmalloc allocator. Use lttng_kvfree to free the memory.
 *
 * Reclaim modifiers - __GFP_NORETRY, __GFP_REPEAT and __GFP_NOFAIL are not supported
 */
static inline
void *lttng_kvmalloc_node(unsigned long size, gfp_t flags, int node)
{
	void *ret;

	/*
	 * vmalloc uses GFP_KERNEL for some internal allocations (e.g page tables)
	 * so the given set of flags has to be compatible.
	 */
	WARN_ON_ONCE((flags & GFP_KERNEL) != GFP_KERNEL);

	/*
	 * If the allocation fits in a single page, do not fallback.
	 */
	if (size <= PAGE_SIZE) {
		return kmalloc_node(size, flags, node);
	}

	/*
	 * Make sure that larger requests are not too disruptive - no OOM
	 * killer and no allocation failure warnings as we have a fallback
	 */
	ret = kmalloc_node(size, flags | __GFP_NOWARN | __GFP_NORETRY, node);
	if (!ret) {
		ret = __lttng_vmalloc_node_range(size, 1,
				VMALLOC_START, VMALLOC_END,
				flags | __GFP_HIGHMEM, PAGE_KERNEL, 0,
				node, __builtin_return_address(0));
		/*
		 * Make sure we don't trigger recursive page faults in the
		 * tracing fast path.
		 */
		wrapper_vmalloc_sync_mappings();
	}
	return ret;
}

static inline
void *lttng_kvzalloc_node(unsigned long size, gfp_t flags, int node)
{
	return lttng_kvmalloc_node(size, flags | __GFP_ZERO, node);
}

static inline
void *lttng_kvmalloc(unsigned long size, gfp_t flags)
{
	return lttng_kvmalloc_node(size, flags, NUMA_NO_NODE);
}

static inline
void *lttng_kvzalloc(unsigned long size, gfp_t flags)
{
	return lttng_kvzalloc_node(size, flags, NUMA_NO_NODE);
}

static inline
void lttng_kvfree(const void *addr)
{
	if (is_vmalloc_addr(addr)) {
		vfree(addr);
	} else {
		kfree(addr);
	}
}
#endif

#endif /* _LTTNG_WRAPPER_VMALLOC_H */
Commit	Line	Data
b7cdc182	1	/* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only)
9f36eaed	2	*
886d51a3	3	* wrapper/vmalloc.h
6d2a620c MD	4	*
	5	* wrapper around vmalloc_sync_all. Using KALLSYMS to get its address when
	6	* available, else we need to have a kernel that exports this function to GPL
	7	* modules.
	8	*
886d51a3	9	* Copyright (C) 2011-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
6d2a620c MD	10	*/
6d2a620c MD	11
9f36eaed MJ	12	#ifndef _LTTNG_WRAPPER_VMALLOC_H
	13	#define _LTTNG_WRAPPER_VMALLOC_H
	14
48f5e0b5 MJ	15	#include <linux/version.h>
48f5e0b5 MJ	16	#include <linux/vmalloc.h>
01ab5113	17	#include <linux/mm.h>
48f5e0b5	18
6d2a620c MD	19	#ifdef CONFIG_KALLSYMS
	20
	21	#include <linux/kallsyms.h>
5a2f5e92	22	#include <wrapper/kallsyms.h>
2b3dbafc	23	#include <lttng/kernel-version.h>
6d2a620c	24
2b3dbafc	25	#if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,6,0) \
9bfe744a	26	\|\| LTTNG_KERNEL_RANGE(5,5,12, 5,6,0) \
2b3dbafc OP	27	\|\| LTTNG_KERNEL_RANGE(5,4,28, 5,5,0) \
	28	\|\| LTTNG_KERNEL_RANGE(5,2,37, 5,3,0) \
	29	\|\| LTTNG_KERNEL_RANGE(4,19,113, 4,20,0) \
	30	\|\| LTTNG_KERNEL_RANGE(4,14,175, 4,15,0) \
	31	\|\| LTTNG_KERNEL_RANGE(4,9,218, 4,10,0) \
2e4c781e SB	32	\|\| LTTNG_KERNEL_RANGE(4,4,218, 4,5,0)) \
	33	\|\| LTTNG_UBUNTU_KERNEL_RANGE(4,15,18,97, 4,16,0,0) \
	34	\|\| LTTNG_UBUNTU_KERNEL_RANGE(5,0,21,48, 5,1,0,0) \
	35	\|\| LTTNG_UBUNTU_KERNEL_RANGE(5,3,18,52, 5,4,0,0)
263b6c88 MD	36
	37	static inline
	38	void wrapper_vmalloc_sync_mappings(void)
	39	{
	40	void (*vmalloc_sync_mappings_sym)(void);
	41
	42	vmalloc_sync_mappings_sym = (void *) kallsyms_lookup_funcptr("vmalloc_sync_mappings");
	43	if (vmalloc_sync_mappings_sym) {
	44	vmalloc_sync_mappings_sym();
	45	} else {
	46	#ifdef CONFIG_X86
	47	/*
	48	* Only x86 needs vmalloc_sync_mappings to make sure LTTng does not
	49	* trigger recursive page faults.
	50	*/
	51	printk_once(KERN_WARNING "LTTng: vmalloc_sync_mappings symbol lookup failed.\n");
	52	printk_once(KERN_WARNING "Page fault handler and NMI tracing might trigger faults.\n");
	53	#endif
	54	}
	55	}
	56
1d618748	57	#else /* #if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,6,0)) */
263b6c88 MD	58
	59	/*
	60	* Map vmalloc_sync_mappings to vmalloc_sync_all() on kernels before 5.7.
	61	*/
6d2a620c	62	static inline
263b6c88	63	void wrapper_vmalloc_sync_mappings(void)
6d2a620c MD	64	{
	65	void (*vmalloc_sync_all_sym)(void);
	66
c539a324	67	vmalloc_sync_all_sym = (void *) kallsyms_lookup_funcptr("vmalloc_sync_all");
6d2a620c MD	68	if (vmalloc_sync_all_sym) {
	69	vmalloc_sync_all_sym();
	70	} else {
	71	#ifdef CONFIG_X86
	72	/*
	73	* Only x86 needs vmalloc_sync_all to make sure LTTng does not
	74	* trigger recursive page faults.
	75	*/
e36de50d MD	76	printk_once(KERN_WARNING "LTTng: vmalloc_sync_all symbol lookup failed.\n");
e36de50d MD	77	printk_once(KERN_WARNING "Page fault handler and NMI tracing might trigger faults.\n");
6d2a620c MD	78	#endif
	79	}
	80	}
263b6c88	81
1d618748	82	#endif /* #else #if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,6,0)) */
263b6c88	83
6d2a620c MD	84	#else
6d2a620c MD	85
2b3dbafc	86	#if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,6,0) \
9bfe744a	87	\|\| LTTNG_KERNEL_RANGE(5,5,12, 5,6,0) \
2b3dbafc OP	88	\|\| LTTNG_KERNEL_RANGE(5,4,28, 5,5,0) \
	89	\|\| LTTNG_KERNEL_RANGE(5,2,37, 5,3,0) \
	90	\|\| LTTNG_KERNEL_RANGE(4,19,113, 4,20,0) \
	91	\|\| LTTNG_KERNEL_RANGE(4,14,175, 4,15,0) \
	92	\|\| LTTNG_KERNEL_RANGE(4,9,218, 4,10,0) \
2e4c781e SB	93	\|\| LTTNG_KERNEL_RANGE(4,4,218, 4,5,0)) \
	94	\|\| LTTNG_UBUNTU_KERNEL_RANGE(4,15,18,97, 4,18,0,0) \
	95	\|\| LTTNG_UBUNTU_KERNEL_RANGE(5,0,21,48, 5,1,0,0) \
	96	\|\| LTTNG_UBUNTU_KERNEL_RANGE(5,3,18,52, 5,4,0,0)
263b6c88	97
6d2a620c	98	static inline
263b6c88 MD	99	void wrapper_vmalloc_sync_mappings(void)
	100	{
	101	return vmalloc_sync_mappings();
	102	}
	103
1d618748	104	#else /* #if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,6,0)) */
263b6c88 MD	105
	106	static inline
	107	void wrapper_vmalloc_sync_mappings(void)
6d2a620c MD	108	{
	109	return vmalloc_sync_all();
	110	}
263b6c88	111
1d618748	112	#endif /* #else #if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,6,0)) */
263b6c88	113
6d2a620c	114	#endif
b13f3ebe	115
48f5e0b5 MJ	116	#if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,12,0))
	117	static inline
	118	void *lttng_kvmalloc_node(unsigned long size, gfp_t flags, int node)
	119	{
	120	void *ret;
	121
	122	ret = kvmalloc_node(size, flags, node);
	123	if (is_vmalloc_addr(ret)) {
	124	/*
	125	* Make sure we don't trigger recursive page faults in the
	126	* tracing fast path.
	127	*/
263b6c88	128	wrapper_vmalloc_sync_mappings();
48f5e0b5 MJ	129	}
	130	return ret;
	131	}
	132
	133	static inline
	134	void *lttng_kvzalloc_node(unsigned long size, gfp_t flags, int node)
	135	{
	136	return lttng_kvmalloc_node(size, flags \| __GFP_ZERO, node);
	137	}
	138
	139	static inline
	140	void *lttng_kvmalloc(unsigned long size, gfp_t flags)
	141	{
	142	return lttng_kvmalloc_node(size, flags, NUMA_NO_NODE);
	143	}
	144
	145	static inline
	146	void *lttng_kvzalloc(unsigned long size, gfp_t flags)
	147	{
	148	return lttng_kvzalloc_node(size, flags, NUMA_NO_NODE);
	149	}
	150
	151	static inline
	152	void lttng_kvfree(const void *addr)
	153	{
	154	kvfree(addr);
	155	}
	156
	157	#else
	158
	159	#include <linux/slab.h>
48f5e0b5	160
20eb87c9 MD	161	static inline
	162	void print_vmalloc_node_range_warning(void)
	163	{
	164	printk_once(KERN_WARNING "LTTng: __vmalloc_node_range symbol lookup failed.\n");
	165	printk_once(KERN_WARNING "Tracer performance will be degraded on NUMA systems.\n");
	166	printk_once(KERN_WARNING "Please rebuild your kernel with CONFIG_KALLSYMS enabled.\n");
	167	}
	168
48f5e0b5 MJ	169	/*
	170	* kallsyms wrapper of __vmalloc_node with a fallback to kmalloc_node.
	171	*/
	172	static inline
20eb87c9 MD	173	void *__lttng_vmalloc_node_range(unsigned long size, unsigned long align,
	174	unsigned long start, unsigned long end, gfp_t gfp_mask,
	175	pgprot_t prot, unsigned long vm_flags, int node,
	176	const void *caller)
48f5e0b5	177	{
48f5e0b5 MJ	178	#ifdef CONFIG_KALLSYMS
48f5e0b5 MJ	179	/*
20eb87c9	180	* If we have KALLSYMS, get * __vmalloc_node_range which is not exported.
48f5e0b5	181	*/
20eb87c9 MD	182	void (lttng__vmalloc_node_range)(unsigned long size, unsigned long align,
	183	unsigned long start, unsigned long end, gfp_t gfp_mask,
	184	pgprot_t prot, unsigned long vm_flags, int node,
	185	const void *caller);
	186
	187	lttng__vmalloc_node_range = (void *) kallsyms_lookup_funcptr("__vmalloc_node_range");
	188	if (lttng__vmalloc_node_range)
	189	return lttng__vmalloc_node_range(size, align, start, end, gfp_mask, prot,
	190	vm_flags, node, caller);
48f5e0b5	191	#endif
20eb87c9 MD	192	if (node != NUMA_NO_NODE)
	193	print_vmalloc_node_range_warning();
	194	return __vmalloc(size, gfp_mask, prot);
48f5e0b5 MJ	195	}
	196
	197	/**
	198	* lttng_kvmalloc_node - attempt to allocate physically contiguous memory, but upon
	199	* failure, fall back to non-contiguous (vmalloc) allocation.
	200	* @size: size of the request.
	201	* @flags: gfp mask for the allocation - must be compatible with GFP_KERNEL.
	202	*
	203	* Uses kmalloc to get the memory but if the allocation fails then falls back
	204	* to the vmalloc allocator. Use lttng_kvfree to free the memory.
	205	*
	206	* Reclaim modifiers - __GFP_NORETRY, __GFP_REPEAT and __GFP_NOFAIL are not supported
	207	*/
	208	static inline
	209	void *lttng_kvmalloc_node(unsigned long size, gfp_t flags, int node)
	210	{
	211	void *ret;
	212
	213	/*
	214	* vmalloc uses GFP_KERNEL for some internal allocations (e.g page tables)
	215	* so the given set of flags has to be compatible.
	216	*/
	217	WARN_ON_ONCE((flags & GFP_KERNEL) != GFP_KERNEL);
	218
	219	/*
	220	* If the allocation fits in a single page, do not fallback.
	221	*/
	222	if (size <= PAGE_SIZE) {
	223	return kmalloc_node(size, flags, node);
	224	}
	225
	226	/*
	227	* Make sure that larger requests are not too disruptive - no OOM
	228	* killer and no allocation failure warnings as we have a fallback
	229	*/
	230	ret = kmalloc_node(size, flags \| __GFP_NOWARN \| __GFP_NORETRY, node);
	231	if (!ret) {
20eb87c9 MD	232	ret = __lttng_vmalloc_node_range(size, 1,
	233	VMALLOC_START, VMALLOC_END,
	234	flags \| __GFP_HIGHMEM, PAGE_KERNEL, 0,
	235	node, __builtin_return_address(0));
48f5e0b5 MJ	236	/*
	237	* Make sure we don't trigger recursive page faults in the
	238	* tracing fast path.
	239	*/
f3e4ba5d	240	wrapper_vmalloc_sync_mappings();
48f5e0b5 MJ	241	}
	242	return ret;
	243	}
	244
	245	static inline
	246	void *lttng_kvzalloc_node(unsigned long size, gfp_t flags, int node)
	247	{
	248	return lttng_kvmalloc_node(size, flags \| __GFP_ZERO, node);
	249	}
	250
	251	static inline
	252	void *lttng_kvmalloc(unsigned long size, gfp_t flags)
	253	{
	254	return lttng_kvmalloc_node(size, flags, NUMA_NO_NODE);
	255	}
	256
	257	static inline
	258	void *lttng_kvzalloc(unsigned long size, gfp_t flags)
	259	{
	260	return lttng_kvzalloc_node(size, flags, NUMA_NO_NODE);
	261	}
	262
	263	static inline
	264	void lttng_kvfree(const void *addr)
	265	{
	266	if (is_vmalloc_addr(addr)) {
	267	vfree(addr);
	268	} else {
	269	kfree(addr);
	270	}
	271	}
	272	#endif
	273
a90917c3	274	#endif /* _LTTNG_WRAPPER_VMALLOC_H */