[linux-block.git] / mm / util.c

#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/export.h>
#include <linux/err.h>
#include <linux/sched.h>
#include <linux/security.h>
#include <asm/uaccess.h>

#include "internal.h"

#define CREATE_TRACE_POINTS
#include <trace/events/kmem.h>

/**
 * kstrdup - allocate space for and copy an existing string
 * @s: the string to duplicate
 * @gfp: the GFP mask used in the kmalloc() call when allocating memory
 */
char *kstrdup(const char *s, gfp_t gfp)
{
	size_t len;
	char *buf;

	if (!s)
		return NULL;

	len = strlen(s) + 1;
	buf = kmalloc_track_caller(len, gfp);
	if (buf)
		memcpy(buf, s, len);
	return buf;
}
EXPORT_SYMBOL(kstrdup);

/**
 * kstrndup - allocate space for and copy an existing string
 * @s: the string to duplicate
 * @max: read at most @max chars from @s
 * @gfp: the GFP mask used in the kmalloc() call when allocating memory
 */
char *kstrndup(const char *s, size_t max, gfp_t gfp)
{
	size_t len;
	char *buf;

	if (!s)
		return NULL;

	len = strnlen(s, max);
	buf = kmalloc_track_caller(len+1, gfp);
	if (buf) {
		memcpy(buf, s, len);
		buf[len] = '\0';
	}
	return buf;
}
EXPORT_SYMBOL(kstrndup);

/**
 * kmemdup - duplicate region of memory
 *
 * @src: memory region to duplicate
 * @len: memory region length
 * @gfp: GFP mask to use
 */
void *kmemdup(const void *src, size_t len, gfp_t gfp)
{
	void *p;

	p = kmalloc_track_caller(len, gfp);
	if (p)
		memcpy(p, src, len);
	return p;
}
EXPORT_SYMBOL(kmemdup);

/**
 * memdup_user - duplicate memory region from user space
 *
 * @src: source address in user space
 * @len: number of bytes to copy
 *
 * Returns an ERR_PTR() on failure.
 */
void *memdup_user(const void __user *src, size_t len)
{
	void *p;

	/*
	 * Always use GFP_KERNEL, since copy_from_user() can sleep and
	 * cause pagefault, which makes it pointless to use GFP_NOFS
	 * or GFP_ATOMIC.
	 */
	p = kmalloc_track_caller(len, GFP_KERNEL);
	if (!p)
		return ERR_PTR(-ENOMEM);

	if (copy_from_user(p, src, len)) {
		kfree(p);
		return ERR_PTR(-EFAULT);
	}

	return p;
}
EXPORT_SYMBOL(memdup_user);

static __always_inline void *__do_krealloc(const void *p, size_t new_size,
					   gfp_t flags)
{
	void *ret;
	size_t ks = 0;

	if (p)
		ks = ksize(p);

	if (ks >= new_size)
		return (void *)p;

	ret = kmalloc_track_caller(new_size, flags);
	if (ret && p)
		memcpy(ret, p, ks);

	return ret;
}

/**
 * __krealloc - like krealloc() but don't free @p.
 * @p: object to reallocate memory for.
 * @new_size: how many bytes of memory are required.
 * @flags: the type of memory to allocate.
 *
 * This function is like krealloc() except it never frees the originally
 * allocated buffer. Use this if you don't want to free the buffer immediately
 * like, for example, with RCU.
 */
void *__krealloc(const void *p, size_t new_size, gfp_t flags)
{
	if (unlikely(!new_size))
		return ZERO_SIZE_PTR;

	return __do_krealloc(p, new_size, flags);

}
EXPORT_SYMBOL(__krealloc);

/**
 * krealloc - reallocate memory. The contents will remain unchanged.
 * @p: object to reallocate memory for.
 * @new_size: how many bytes of memory are required.
 * @flags: the type of memory to allocate.
 *
 * The contents of the object pointed to are preserved up to the
 * lesser of the new and old sizes.  If @p is %NULL, krealloc()
 * behaves exactly like kmalloc().  If @new_size is 0 and @p is not a
 * %NULL pointer, the object pointed to is freed.
 */
void *krealloc(const void *p, size_t new_size, gfp_t flags)
{
	void *ret;

	if (unlikely(!new_size)) {
		kfree(p);
		return ZERO_SIZE_PTR;
	}

	ret = __do_krealloc(p, new_size, flags);
	if (ret && p != ret)
		kfree(p);

	return ret;
}
EXPORT_SYMBOL(krealloc);

/**
 * kzfree - like kfree but zero memory
 * @p: object to free memory of
 *
 * The memory of the object @p points to is zeroed before freed.
 * If @p is %NULL, kzfree() does nothing.
 *
 * Note: this function zeroes the whole allocated buffer which can be a good
 * deal bigger than the requested buffer size passed to kmalloc(). So be
 * careful when using this function in performance sensitive code.
 */
void kzfree(const void *p)
{
	size_t ks;
	void *mem = (void *)p;

	if (unlikely(ZERO_OR_NULL_PTR(mem)))
		return;
	ks = ksize(mem);
	memset(mem, 0, ks);
	kfree(mem);
}
EXPORT_SYMBOL(kzfree);

/*
 * strndup_user - duplicate an existing string from user space
 * @s: The string to duplicate
 * @n: Maximum number of bytes to copy, including the trailing NUL.
 */
char *strndup_user(const char __user *s, long n)
{
	char *p;
	long length;

	length = strnlen_user(s, n);

	if (!length)
		return ERR_PTR(-EFAULT);

	if (length > n)
		return ERR_PTR(-EINVAL);

	p = memdup_user(s, length);

	if (IS_ERR(p))
		return p;

	p[length - 1] = '\0';

	return p;
}
EXPORT_SYMBOL(strndup_user);

void __vma_link_list(struct mm_struct *mm, struct vm_area_struct *vma,
		struct vm_area_struct *prev, struct rb_node *rb_parent)
{
	struct vm_area_struct *next;

	vma->vm_prev = prev;
	if (prev) {
		next = prev->vm_next;
		prev->vm_next = vma;
	} else {
		mm->mmap = vma;
		if (rb_parent)
			next = rb_entry(rb_parent,
					struct vm_area_struct, vm_rb);
		else
			next = NULL;
	}
	vma->vm_next = next;
	if (next)
		next->vm_prev = vma;
}

/* Check if the vma is being used as a stack by this task */
static int vm_is_stack_for_task(struct task_struct *t,
				struct vm_area_struct *vma)
{
	return (vma->vm_start <= KSTK_ESP(t) && vma->vm_end >= KSTK_ESP(t));
}

/*
 * Check if the vma is being used as a stack.
 * If is_group is non-zero, check in the entire thread group or else
 * just check in the current task. Returns the pid of the task that
 * the vma is stack for.
 */
pid_t vm_is_stack(struct task_struct *task,
		  struct vm_area_struct *vma, int in_group)
{
	pid_t ret = 0;

	if (vm_is_stack_for_task(task, vma))
		return task->pid;

	if (in_group) {
		struct task_struct *t;
		rcu_read_lock();
		if (!pid_alive(task))
			goto done;

		t = task;
		do {
			if (vm_is_stack_for_task(t, vma)) {
				ret = t->pid;
				goto done;
			}
		} while_each_thread(task, t);
done:
		rcu_read_unlock();
	}

	return ret;
}

#if defined(CONFIG_MMU) && !defined(HAVE_ARCH_PICK_MMAP_LAYOUT)
void arch_pick_mmap_layout(struct mm_struct *mm)
{
	mm->mmap_base = TASK_UNMAPPED_BASE;
	mm->get_unmapped_area = arch_get_unmapped_area;
	mm->unmap_area = arch_unmap_area;
}
#endif

/*
 * Like get_user_pages_fast() except its IRQ-safe in that it won't fall
 * back to the regular GUP.
 * If the architecture not support this function, simply return with no
 * page pinned
 */
int __attribute__((weak)) __get_user_pages_fast(unsigned long start,
				 int nr_pages, int write, struct page **pages)
{
	return 0;
}
EXPORT_SYMBOL_GPL(__get_user_pages_fast);

/**
 * get_user_pages_fast() - pin user pages in memory
 * @start:	starting user address
 * @nr_pages:	number of pages from start to pin
 * @write:	whether pages will be written to
 * @pages:	array that receives pointers to the pages pinned.
 *		Should be at least nr_pages long.
 *
 * Returns number of pages pinned. This may be fewer than the number
 * requested. If nr_pages is 0 or negative, returns 0. If no pages
 * were pinned, returns -errno.
 *
 * get_user_pages_fast provides equivalent functionality to get_user_pages,
 * operating on current and current->mm, with force=0 and vma=NULL. However
 * unlike get_user_pages, it must be called without mmap_sem held.
 *
 * get_user_pages_fast may take mmap_sem and page table locks, so no
 * assumptions can be made about lack of locking. get_user_pages_fast is to be
 * implemented in a way that is advantageous (vs get_user_pages()) when the
 * user memory area is already faulted in and present in ptes. However if the
 * pages have to be faulted in, it may turn out to be slightly slower so
 * callers need to carefully consider what to use. On many architectures,
 * get_user_pages_fast simply falls back to get_user_pages.
 */
int __attribute__((weak)) get_user_pages_fast(unsigned long start,
				int nr_pages, int write, struct page **pages)
{
	struct mm_struct *mm = current->mm;
	int ret;

	down_read(&mm->mmap_sem);
	ret = get_user_pages(current, mm, start, nr_pages,
					write, 0, pages, NULL);
	up_read(&mm->mmap_sem);

	return ret;
}
EXPORT_SYMBOL_GPL(get_user_pages_fast);

unsigned long vm_mmap_pgoff(struct file *file, unsigned long addr,
	unsigned long len, unsigned long prot,
	unsigned long flag, unsigned long pgoff)
{
	unsigned long ret;
	struct mm_struct *mm = current->mm;
	unsigned long populate;

	ret = security_mmap_file(file, prot, flag);
	if (!ret) {
		down_write(&mm->mmap_sem);
		ret = do_mmap_pgoff(file, addr, len, prot, flag, pgoff,
				    &populate);
		up_write(&mm->mmap_sem);
		if (populate)
			mm_populate(ret, populate);
	}
	return ret;
}

unsigned long vm_mmap(struct file *file, unsigned long addr,
	unsigned long len, unsigned long prot,
	unsigned long flag, unsigned long offset)
{
	if (unlikely(offset + PAGE_ALIGN(len) < offset))
		return -EINVAL;
	if (unlikely(offset & ~PAGE_MASK))
		return -EINVAL;

	return vm_mmap_pgoff(file, addr, len, prot, flag, offset >> PAGE_SHIFT);
}
EXPORT_SYMBOL(vm_mmap);

/* Tracepoints definitions. */
EXPORT_TRACEPOINT_SYMBOL(kmalloc);
EXPORT_TRACEPOINT_SYMBOL(kmem_cache_alloc);
EXPORT_TRACEPOINT_SYMBOL(kmalloc_node);
EXPORT_TRACEPOINT_SYMBOL(kmem_cache_alloc_node);
EXPORT_TRACEPOINT_SYMBOL(kfree);
EXPORT_TRACEPOINT_SYMBOL(kmem_cache_free);
Commit	Line	Data
16d69265	1	#include <linux/mm.h>
30992c97 MM	2	#include <linux/slab.h>
30992c97 MM	3	#include <linux/string.h>
b95f1b31	4	#include <linux/export.h>
96840aa0	5	#include <linux/err.h>
3b8f14b4	6	#include <linux/sched.h>
eb36c587	7	#include <linux/security.h>
96840aa0	8	#include <asm/uaccess.h>
30992c97	9
6038def0 NK	10	#include "internal.h"
6038def0 NK	11
a8d154b0	12	#define CREATE_TRACE_POINTS
ad8d75ff	13	#include <trace/events/kmem.h>
a8d154b0	14
30992c97	15	/**
30992c97	16	* kstrdup - allocate space for and copy an existing string
30992c97 MM	17	* @s: the string to duplicate
	18	* @gfp: the GFP mask used in the kmalloc() call when allocating memory
	19	*/
	20	char kstrdup(const char s, gfp_t gfp)
	21	{
	22	size_t len;
	23	char *buf;
	24
	25	if (!s)
	26	return NULL;
	27
	28	len = strlen(s) + 1;
1d2c8eea	29	buf = kmalloc_track_caller(len, gfp);
30992c97 MM	30	if (buf)
	31	memcpy(buf, s, len);
	32	return buf;
	33	}
	34	EXPORT_SYMBOL(kstrdup);
96840aa0	35
1e66df3e JF	36	/**
	37	* kstrndup - allocate space for and copy an existing string
	38	* @s: the string to duplicate
	39	* @max: read at most @max chars from @s
	40	* @gfp: the GFP mask used in the kmalloc() call when allocating memory
	41	*/
	42	char kstrndup(const char s, size_t max, gfp_t gfp)
	43	{
	44	size_t len;
	45	char *buf;
	46
	47	if (!s)
	48	return NULL;
	49
	50	len = strnlen(s, max);
	51	buf = kmalloc_track_caller(len+1, gfp);
	52	if (buf) {
	53	memcpy(buf, s, len);
	54	buf[len] = '\0';
	55	}
	56	return buf;
	57	}
	58	EXPORT_SYMBOL(kstrndup);
	59
1a2f67b4 AD	60	/**
	61	* kmemdup - duplicate region of memory
	62	*
	63	* @src: memory region to duplicate
	64	* @len: memory region length
	65	* @gfp: GFP mask to use
	66	*/
	67	void kmemdup(const void src, size_t len, gfp_t gfp)
	68	{
	69	void *p;
	70
1d2c8eea	71	p = kmalloc_track_caller(len, gfp);
1a2f67b4 AD	72	if (p)
	73	memcpy(p, src, len);
	74	return p;
	75	}
	76	EXPORT_SYMBOL(kmemdup);
	77
610a77e0 LZ	78	/**
	79	* memdup_user - duplicate memory region from user space
	80	*
	81	* @src: source address in user space
	82	* @len: number of bytes to copy
	83	*
	84	* Returns an ERR_PTR() on failure.
	85	*/
	86	void memdup_user(const void __user src, size_t len)
	87	{
	88	void *p;
	89
	90	/*
	91	* Always use GFP_KERNEL, since copy_from_user() can sleep and
	92	* cause pagefault, which makes it pointless to use GFP_NOFS
	93	* or GFP_ATOMIC.
	94	*/
	95	p = kmalloc_track_caller(len, GFP_KERNEL);
	96	if (!p)
	97	return ERR_PTR(-ENOMEM);
	98
	99	if (copy_from_user(p, src, len)) {
	100	kfree(p);
	101	return ERR_PTR(-EFAULT);
	102	}
	103
	104	return p;
	105	}
	106	EXPORT_SYMBOL(memdup_user);
	107
e21827aa EG	108	static __always_inline void __do_krealloc(const void p, size_t new_size,
	109	gfp_t flags)
	110	{
	111	void *ret;
	112	size_t ks = 0;
	113
	114	if (p)
	115	ks = ksize(p);
	116
	117	if (ks >= new_size)
	118	return (void *)p;
	119
	120	ret = kmalloc_track_caller(new_size, flags);
	121	if (ret && p)
	122	memcpy(ret, p, ks);
	123
	124	return ret;
	125	}
	126
ef2ad80c	127	/**
93bc4e89	128	* __krealloc - like krealloc() but don't free @p.
ef2ad80c CL	129	* @p: object to reallocate memory for.
	130	* @new_size: how many bytes of memory are required.
	131	* @flags: the type of memory to allocate.
	132	*
93bc4e89 PE	133	* This function is like krealloc() except it never frees the originally
	134	* allocated buffer. Use this if you don't want to free the buffer immediately
	135	* like, for example, with RCU.
ef2ad80c	136	*/
93bc4e89	137	void __krealloc(const void p, size_t new_size, gfp_t flags)
ef2ad80c	138	{
93bc4e89	139	if (unlikely(!new_size))
6cb8f913	140	return ZERO_SIZE_PTR;
ef2ad80c	141
e21827aa	142	return __do_krealloc(p, new_size, flags);
ef8b4520	143
93bc4e89 PE	144	}
	145	EXPORT_SYMBOL(__krealloc);
	146
	147	/**
	148	* krealloc - reallocate memory. The contents will remain unchanged.
	149	* @p: object to reallocate memory for.
	150	* @new_size: how many bytes of memory are required.
	151	* @flags: the type of memory to allocate.
	152	*
	153	* The contents of the object pointed to are preserved up to the
	154	* lesser of the new and old sizes. If @p is %NULL, krealloc()
0db10c8e	155	* behaves exactly like kmalloc(). If @new_size is 0 and @p is not a
93bc4e89 PE	156	* %NULL pointer, the object pointed to is freed.
	157	*/
	158	void krealloc(const void p, size_t new_size, gfp_t flags)
	159	{
	160	void *ret;
	161
	162	if (unlikely(!new_size)) {
ef2ad80c	163	kfree(p);
93bc4e89	164	return ZERO_SIZE_PTR;
ef2ad80c	165	}
93bc4e89	166
e21827aa	167	ret = __do_krealloc(p, new_size, flags);
93bc4e89 PE	168	if (ret && p != ret)
	169	kfree(p);
	170
ef2ad80c CL	171	return ret;
	172	}
	173	EXPORT_SYMBOL(krealloc);
	174
3ef0e5ba JW	175	/**
	176	* kzfree - like kfree but zero memory
	177	* @p: object to free memory of
	178	*
	179	* The memory of the object @p points to is zeroed before freed.
	180	* If @p is %NULL, kzfree() does nothing.
a234bdc9 PE	181	*
	182	* Note: this function zeroes the whole allocated buffer which can be a good
	183	* deal bigger than the requested buffer size passed to kmalloc(). So be
	184	* careful when using this function in performance sensitive code.
3ef0e5ba JW	185	*/
	186	void kzfree(const void *p)
	187	{
	188	size_t ks;
	189	void mem = (void )p;
	190
	191	if (unlikely(ZERO_OR_NULL_PTR(mem)))
	192	return;
	193	ks = ksize(mem);
	194	memset(mem, 0, ks);
	195	kfree(mem);
	196	}
	197	EXPORT_SYMBOL(kzfree);
	198
96840aa0 DA	199	/*
96840aa0 DA	200	* strndup_user - duplicate an existing string from user space
96840aa0 DA	201	* @s: The string to duplicate
	202	* @n: Maximum number of bytes to copy, including the trailing NUL.
	203	*/
	204	char strndup_user(const char __user s, long n)
	205	{
	206	char *p;
	207	long length;
	208
	209	length = strnlen_user(s, n);
	210
	211	if (!length)
	212	return ERR_PTR(-EFAULT);
	213
	214	if (length > n)
	215	return ERR_PTR(-EINVAL);
	216
90d74045	217	p = memdup_user(s, length);
96840aa0	218
90d74045 JL	219	if (IS_ERR(p))
90d74045 JL	220	return p;
96840aa0 DA	221
	222	p[length - 1] = '\0';
	223
	224	return p;
	225	}
	226	EXPORT_SYMBOL(strndup_user);
16d69265	227
6038def0 NK	228	void __vma_link_list(struct mm_struct mm, struct vm_area_struct vma,
	229	struct vm_area_struct prev, struct rb_node rb_parent)
	230	{
	231	struct vm_area_struct *next;
	232
	233	vma->vm_prev = prev;
	234	if (prev) {
	235	next = prev->vm_next;
	236	prev->vm_next = vma;
	237	} else {
	238	mm->mmap = vma;
	239	if (rb_parent)
	240	next = rb_entry(rb_parent,
	241	struct vm_area_struct, vm_rb);
	242	else
	243	next = NULL;
	244	}
	245	vma->vm_next = next;
	246	if (next)
	247	next->vm_prev = vma;
	248	}
	249
b7643757 SP	250	/* Check if the vma is being used as a stack by this task */
	251	static int vm_is_stack_for_task(struct task_struct *t,
	252	struct vm_area_struct *vma)
	253	{
	254	return (vma->vm_start <= KSTK_ESP(t) && vma->vm_end >= KSTK_ESP(t));
	255	}
	256
	257	/*
	258	* Check if the vma is being used as a stack.
	259	* If is_group is non-zero, check in the entire thread group or else
	260	* just check in the current task. Returns the pid of the task that
	261	* the vma is stack for.
	262	*/
	263	pid_t vm_is_stack(struct task_struct *task,
	264	struct vm_area_struct *vma, int in_group)
	265	{
	266	pid_t ret = 0;
	267
	268	if (vm_is_stack_for_task(task, vma))
	269	return task->pid;
	270
	271	if (in_group) {
	272	struct task_struct *t;
	273	rcu_read_lock();
	274	if (!pid_alive(task))
	275	goto done;
	276
	277	t = task;
	278	do {
	279	if (vm_is_stack_for_task(t, vma)) {
	280	ret = t->pid;
	281	goto done;
	282	}
	283	} while_each_thread(task, t);
	284	done:
	285	rcu_read_unlock();
	286	}
	287
	288	return ret;
	289	}
	290
efc1a3b1	291	#if defined(CONFIG_MMU) && !defined(HAVE_ARCH_PICK_MMAP_LAYOUT)
16d69265 AM	292	void arch_pick_mmap_layout(struct mm_struct *mm)
	293	{
	294	mm->mmap_base = TASK_UNMAPPED_BASE;
	295	mm->get_unmapped_area = arch_get_unmapped_area;
	296	mm->unmap_area = arch_unmap_area;
	297	}
	298	#endif
912985dc	299
45888a0c XG	300	/*
	301	* Like get_user_pages_fast() except its IRQ-safe in that it won't fall
	302	* back to the regular GUP.
25985edc	303	* If the architecture not support this function, simply return with no
45888a0c XG	304	* page pinned
	305	*/
	306	int __attribute__((weak)) __get_user_pages_fast(unsigned long start,
	307	int nr_pages, int write, struct page **pages)
	308	{
	309	return 0;
	310	}
	311	EXPORT_SYMBOL_GPL(__get_user_pages_fast);
	312
9de100d0 AG	313	/**
	314	* get_user_pages_fast() - pin user pages in memory
	315	* @start: starting user address
	316	* @nr_pages: number of pages from start to pin
	317	* @write: whether pages will be written to
	318	* @pages: array that receives pointers to the pages pinned.
	319	* Should be at least nr_pages long.
	320	*
9de100d0 AG	321	* Returns number of pages pinned. This may be fewer than the number
	322	* requested. If nr_pages is 0 or negative, returns 0. If no pages
	323	* were pinned, returns -errno.
d2bf6be8 NP	324	*
	325	* get_user_pages_fast provides equivalent functionality to get_user_pages,
	326	* operating on current and current->mm, with force=0 and vma=NULL. However
	327	* unlike get_user_pages, it must be called without mmap_sem held.
	328	*
	329	* get_user_pages_fast may take mmap_sem and page table locks, so no
	330	* assumptions can be made about lack of locking. get_user_pages_fast is to be
	331	* implemented in a way that is advantageous (vs get_user_pages()) when the
	332	* user memory area is already faulted in and present in ptes. However if the
	333	* pages have to be faulted in, it may turn out to be slightly slower so
	334	* callers need to carefully consider what to use. On many architectures,
	335	* get_user_pages_fast simply falls back to get_user_pages.
9de100d0	336	*/
912985dc RR	337	int __attribute__((weak)) get_user_pages_fast(unsigned long start,
	338	int nr_pages, int write, struct page **pages)
	339	{
	340	struct mm_struct *mm = current->mm;
	341	int ret;
	342
	343	down_read(&mm->mmap_sem);
	344	ret = get_user_pages(current, mm, start, nr_pages,
	345	write, 0, pages, NULL);
	346	up_read(&mm->mmap_sem);
	347
	348	return ret;
	349	}
	350	EXPORT_SYMBOL_GPL(get_user_pages_fast);
ca2b84cb	351
eb36c587 AV	352	unsigned long vm_mmap_pgoff(struct file *file, unsigned long addr,
	353	unsigned long len, unsigned long prot,
	354	unsigned long flag, unsigned long pgoff)
	355	{
	356	unsigned long ret;
	357	struct mm_struct *mm = current->mm;
41badc15	358	unsigned long populate;
eb36c587 AV	359
	360	ret = security_mmap_file(file, prot, flag);
	361	if (!ret) {
	362	down_write(&mm->mmap_sem);
bebeb3d6 ML	363	ret = do_mmap_pgoff(file, addr, len, prot, flag, pgoff,
bebeb3d6 ML	364	&populate);
eb36c587	365	up_write(&mm->mmap_sem);
41badc15 ML	366	if (populate)
41badc15 ML	367	mm_populate(ret, populate);
eb36c587 AV	368	}
	369	return ret;
	370	}
	371
	372	unsigned long vm_mmap(struct file *file, unsigned long addr,
	373	unsigned long len, unsigned long prot,
	374	unsigned long flag, unsigned long offset)
	375	{
	376	if (unlikely(offset + PAGE_ALIGN(len) < offset))
	377	return -EINVAL;
	378	if (unlikely(offset & ~PAGE_MASK))
	379	return -EINVAL;
	380
	381	return vm_mmap_pgoff(file, addr, len, prot, flag, offset >> PAGE_SHIFT);
	382	}
	383	EXPORT_SYMBOL(vm_mmap);
	384
ca2b84cb	385	/* Tracepoints definitions. */
ca2b84cb EGM	386	EXPORT_TRACEPOINT_SYMBOL(kmalloc);
	387	EXPORT_TRACEPOINT_SYMBOL(kmem_cache_alloc);
	388	EXPORT_TRACEPOINT_SYMBOL(kmalloc_node);
	389	EXPORT_TRACEPOINT_SYMBOL(kmem_cache_alloc_node);
	390	EXPORT_TRACEPOINT_SYMBOL(kfree);
	391	EXPORT_TRACEPOINT_SYMBOL(kmem_cache_free);