[linux-2.6-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 <linux/swap.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);

struct address_space *page_mapping(struct page *page)
{
	struct address_space *mapping = page->mapping;

	VM_BUG_ON(PageSlab(page));
#ifdef CONFIG_SWAP
	if (unlikely(PageSwapCache(page)))
		mapping = &swapper_space;
	else
#endif
	if ((unsigned long)mapping & PAGE_MAPPING_ANON)
		mapping = NULL;
	return mapping;
}

/* 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>
9800339b	8	#include <linux/swap.h>
96840aa0	9	#include <asm/uaccess.h>
30992c97	10
6038def0 NK	11	#include "internal.h"
6038def0 NK	12
a8d154b0	13	#define CREATE_TRACE_POINTS
ad8d75ff	14	#include <trace/events/kmem.h>
a8d154b0	15
30992c97	16	/**
30992c97	17	* kstrdup - allocate space for and copy an existing string
30992c97 MM	18	* @s: the string to duplicate
	19	* @gfp: the GFP mask used in the kmalloc() call when allocating memory
	20	*/
	21	char kstrdup(const char s, gfp_t gfp)
	22	{
	23	size_t len;
	24	char *buf;
	25
	26	if (!s)
	27	return NULL;
	28
	29	len = strlen(s) + 1;
1d2c8eea	30	buf = kmalloc_track_caller(len, gfp);
30992c97 MM	31	if (buf)
	32	memcpy(buf, s, len);
	33	return buf;
	34	}
	35	EXPORT_SYMBOL(kstrdup);
96840aa0	36
1e66df3e JF	37	/**
	38	* kstrndup - allocate space for and copy an existing string
	39	* @s: the string to duplicate
	40	* @max: read at most @max chars from @s
	41	* @gfp: the GFP mask used in the kmalloc() call when allocating memory
	42	*/
	43	char kstrndup(const char s, size_t max, gfp_t gfp)
	44	{
	45	size_t len;
	46	char *buf;
	47
	48	if (!s)
	49	return NULL;
	50
	51	len = strnlen(s, max);
	52	buf = kmalloc_track_caller(len+1, gfp);
	53	if (buf) {
	54	memcpy(buf, s, len);
	55	buf[len] = '\0';
	56	}
	57	return buf;
	58	}
	59	EXPORT_SYMBOL(kstrndup);
	60
1a2f67b4 AD	61	/**
	62	* kmemdup - duplicate region of memory
	63	*
	64	* @src: memory region to duplicate
	65	* @len: memory region length
	66	* @gfp: GFP mask to use
	67	*/
	68	void kmemdup(const void src, size_t len, gfp_t gfp)
	69	{
	70	void *p;
	71
1d2c8eea	72	p = kmalloc_track_caller(len, gfp);
1a2f67b4 AD	73	if (p)
	74	memcpy(p, src, len);
	75	return p;
	76	}
	77	EXPORT_SYMBOL(kmemdup);
	78
610a77e0 LZ	79	/**
	80	* memdup_user - duplicate memory region from user space
	81	*
	82	* @src: source address in user space
	83	* @len: number of bytes to copy
	84	*
	85	* Returns an ERR_PTR() on failure.
	86	*/
	87	void memdup_user(const void __user src, size_t len)
	88	{
	89	void *p;
	90
	91	/*
	92	* Always use GFP_KERNEL, since copy_from_user() can sleep and
	93	* cause pagefault, which makes it pointless to use GFP_NOFS
	94	* or GFP_ATOMIC.
	95	*/
	96	p = kmalloc_track_caller(len, GFP_KERNEL);
	97	if (!p)
	98	return ERR_PTR(-ENOMEM);
	99
	100	if (copy_from_user(p, src, len)) {
	101	kfree(p);
	102	return ERR_PTR(-EFAULT);
	103	}
	104
	105	return p;
	106	}
	107	EXPORT_SYMBOL(memdup_user);
	108
e21827aa EG	109	static __always_inline void __do_krealloc(const void p, size_t new_size,
	110	gfp_t flags)
	111	{
	112	void *ret;
	113	size_t ks = 0;
	114
	115	if (p)
	116	ks = ksize(p);
	117
	118	if (ks >= new_size)
	119	return (void *)p;
	120
	121	ret = kmalloc_track_caller(new_size, flags);
	122	if (ret && p)
	123	memcpy(ret, p, ks);
	124
	125	return ret;
	126	}
	127
ef2ad80c	128	/**
93bc4e89	129	* __krealloc - like krealloc() but don't free @p.
ef2ad80c CL	130	* @p: object to reallocate memory for.
	131	* @new_size: how many bytes of memory are required.
	132	* @flags: the type of memory to allocate.
	133	*
93bc4e89 PE	134	* This function is like krealloc() except it never frees the originally
	135	* allocated buffer. Use this if you don't want to free the buffer immediately
	136	* like, for example, with RCU.
ef2ad80c	137	*/
93bc4e89	138	void __krealloc(const void p, size_t new_size, gfp_t flags)
ef2ad80c	139	{
93bc4e89	140	if (unlikely(!new_size))
6cb8f913	141	return ZERO_SIZE_PTR;
ef2ad80c	142
e21827aa	143	return __do_krealloc(p, new_size, flags);
ef8b4520	144
93bc4e89 PE	145	}
	146	EXPORT_SYMBOL(__krealloc);
	147
	148	/**
	149	* krealloc - reallocate memory. The contents will remain unchanged.
	150	* @p: object to reallocate memory for.
	151	* @new_size: how many bytes of memory are required.
	152	* @flags: the type of memory to allocate.
	153	*
	154	* The contents of the object pointed to are preserved up to the
	155	* lesser of the new and old sizes. If @p is %NULL, krealloc()
0db10c8e	156	* behaves exactly like kmalloc(). If @new_size is 0 and @p is not a
93bc4e89 PE	157	* %NULL pointer, the object pointed to is freed.
	158	*/
	159	void krealloc(const void p, size_t new_size, gfp_t flags)
	160	{
	161	void *ret;
	162
	163	if (unlikely(!new_size)) {
ef2ad80c	164	kfree(p);
93bc4e89	165	return ZERO_SIZE_PTR;
ef2ad80c	166	}
93bc4e89	167
e21827aa	168	ret = __do_krealloc(p, new_size, flags);
93bc4e89 PE	169	if (ret && p != ret)
	170	kfree(p);
	171
ef2ad80c CL	172	return ret;
	173	}
	174	EXPORT_SYMBOL(krealloc);
	175
3ef0e5ba JW	176	/**
	177	* kzfree - like kfree but zero memory
	178	* @p: object to free memory of
	179	*
	180	* The memory of the object @p points to is zeroed before freed.
	181	* If @p is %NULL, kzfree() does nothing.
a234bdc9 PE	182	*
	183	* Note: this function zeroes the whole allocated buffer which can be a good
	184	* deal bigger than the requested buffer size passed to kmalloc(). So be
	185	* careful when using this function in performance sensitive code.
3ef0e5ba JW	186	*/
	187	void kzfree(const void *p)
	188	{
	189	size_t ks;
	190	void mem = (void )p;
	191
	192	if (unlikely(ZERO_OR_NULL_PTR(mem)))
	193	return;
	194	ks = ksize(mem);
	195	memset(mem, 0, ks);
	196	kfree(mem);
	197	}
	198	EXPORT_SYMBOL(kzfree);
	199
96840aa0 DA	200	/*
96840aa0 DA	201	* strndup_user - duplicate an existing string from user space
96840aa0 DA	202	* @s: The string to duplicate
	203	* @n: Maximum number of bytes to copy, including the trailing NUL.
	204	*/
	205	char strndup_user(const char __user s, long n)
	206	{
	207	char *p;
	208	long length;
	209
	210	length = strnlen_user(s, n);
	211
	212	if (!length)
	213	return ERR_PTR(-EFAULT);
	214
	215	if (length > n)
	216	return ERR_PTR(-EINVAL);
	217
90d74045	218	p = memdup_user(s, length);
96840aa0	219
90d74045 JL	220	if (IS_ERR(p))
90d74045 JL	221	return p;
96840aa0 DA	222
	223	p[length - 1] = '\0';
	224
	225	return p;
	226	}
	227	EXPORT_SYMBOL(strndup_user);
16d69265	228
6038def0 NK	229	void __vma_link_list(struct mm_struct mm, struct vm_area_struct vma,
	230	struct vm_area_struct prev, struct rb_node rb_parent)
	231	{
	232	struct vm_area_struct *next;
	233
	234	vma->vm_prev = prev;
	235	if (prev) {
	236	next = prev->vm_next;
	237	prev->vm_next = vma;
	238	} else {
	239	mm->mmap = vma;
	240	if (rb_parent)
	241	next = rb_entry(rb_parent,
	242	struct vm_area_struct, vm_rb);
	243	else
	244	next = NULL;
	245	}
	246	vma->vm_next = next;
	247	if (next)
	248	next->vm_prev = vma;
	249	}
	250
b7643757 SP	251	/* Check if the vma is being used as a stack by this task */
	252	static int vm_is_stack_for_task(struct task_struct *t,
	253	struct vm_area_struct *vma)
	254	{
	255	return (vma->vm_start <= KSTK_ESP(t) && vma->vm_end >= KSTK_ESP(t));
	256	}
	257
	258	/*
	259	* Check if the vma is being used as a stack.
	260	* If is_group is non-zero, check in the entire thread group or else
	261	* just check in the current task. Returns the pid of the task that
	262	* the vma is stack for.
	263	*/
	264	pid_t vm_is_stack(struct task_struct *task,
	265	struct vm_area_struct *vma, int in_group)
	266	{
	267	pid_t ret = 0;
	268
	269	if (vm_is_stack_for_task(task, vma))
	270	return task->pid;
	271
	272	if (in_group) {
	273	struct task_struct *t;
	274	rcu_read_lock();
	275	if (!pid_alive(task))
	276	goto done;
	277
	278	t = task;
	279	do {
	280	if (vm_is_stack_for_task(t, vma)) {
	281	ret = t->pid;
	282	goto done;
	283	}
	284	} while_each_thread(task, t);
	285	done:
	286	rcu_read_unlock();
	287	}
	288
	289	return ret;
	290	}
	291
efc1a3b1	292	#if defined(CONFIG_MMU) && !defined(HAVE_ARCH_PICK_MMAP_LAYOUT)
16d69265 AM	293	void arch_pick_mmap_layout(struct mm_struct *mm)
	294	{
	295	mm->mmap_base = TASK_UNMAPPED_BASE;
	296	mm->get_unmapped_area = arch_get_unmapped_area;
	297	mm->unmap_area = arch_unmap_area;
	298	}
	299	#endif
912985dc	300
45888a0c XG	301	/*
	302	* Like get_user_pages_fast() except its IRQ-safe in that it won't fall
	303	* back to the regular GUP.
25985edc	304	* If the architecture not support this function, simply return with no
45888a0c XG	305	* page pinned
	306	*/
	307	int __attribute__((weak)) __get_user_pages_fast(unsigned long start,
	308	int nr_pages, int write, struct page **pages)
	309	{
	310	return 0;
	311	}
	312	EXPORT_SYMBOL_GPL(__get_user_pages_fast);
	313
9de100d0 AG	314	/**
	315	* get_user_pages_fast() - pin user pages in memory
	316	* @start: starting user address
	317	* @nr_pages: number of pages from start to pin
	318	* @write: whether pages will be written to
	319	* @pages: array that receives pointers to the pages pinned.
	320	* Should be at least nr_pages long.
	321	*
9de100d0 AG	322	* Returns number of pages pinned. This may be fewer than the number
	323	* requested. If nr_pages is 0 or negative, returns 0. If no pages
	324	* were pinned, returns -errno.
d2bf6be8 NP	325	*
	326	* get_user_pages_fast provides equivalent functionality to get_user_pages,
	327	* operating on current and current->mm, with force=0 and vma=NULL. However
	328	* unlike get_user_pages, it must be called without mmap_sem held.
	329	*
	330	* get_user_pages_fast may take mmap_sem and page table locks, so no
	331	* assumptions can be made about lack of locking. get_user_pages_fast is to be
	332	* implemented in a way that is advantageous (vs get_user_pages()) when the
	333	* user memory area is already faulted in and present in ptes. However if the
	334	* pages have to be faulted in, it may turn out to be slightly slower so
	335	* callers need to carefully consider what to use. On many architectures,
	336	* get_user_pages_fast simply falls back to get_user_pages.
9de100d0	337	*/
912985dc RR	338	int __attribute__((weak)) get_user_pages_fast(unsigned long start,
	339	int nr_pages, int write, struct page **pages)
	340	{
	341	struct mm_struct *mm = current->mm;
	342	int ret;
	343
	344	down_read(&mm->mmap_sem);
	345	ret = get_user_pages(current, mm, start, nr_pages,
	346	write, 0, pages, NULL);
	347	up_read(&mm->mmap_sem);
	348
	349	return ret;
	350	}
	351	EXPORT_SYMBOL_GPL(get_user_pages_fast);
ca2b84cb	352
eb36c587 AV	353	unsigned long vm_mmap_pgoff(struct file *file, unsigned long addr,
	354	unsigned long len, unsigned long prot,
	355	unsigned long flag, unsigned long pgoff)
	356	{
	357	unsigned long ret;
	358	struct mm_struct *mm = current->mm;
41badc15	359	unsigned long populate;
eb36c587 AV	360
	361	ret = security_mmap_file(file, prot, flag);
	362	if (!ret) {
	363	down_write(&mm->mmap_sem);
bebeb3d6 ML	364	ret = do_mmap_pgoff(file, addr, len, prot, flag, pgoff,
bebeb3d6 ML	365	&populate);
eb36c587	366	up_write(&mm->mmap_sem);
41badc15 ML	367	if (populate)
41badc15 ML	368	mm_populate(ret, populate);
eb36c587 AV	369	}
	370	return ret;
	371	}
	372
	373	unsigned long vm_mmap(struct file *file, unsigned long addr,
	374	unsigned long len, unsigned long prot,
	375	unsigned long flag, unsigned long offset)
	376	{
	377	if (unlikely(offset + PAGE_ALIGN(len) < offset))
	378	return -EINVAL;
	379	if (unlikely(offset & ~PAGE_MASK))
	380	return -EINVAL;
	381
	382	return vm_mmap_pgoff(file, addr, len, prot, flag, offset >> PAGE_SHIFT);
	383	}
	384	EXPORT_SYMBOL(vm_mmap);
	385
9800339b SL	386	struct address_space page_mapping(struct page page)
	387	{
	388	struct address_space *mapping = page->mapping;
	389
	390	VM_BUG_ON(PageSlab(page));
	391	#ifdef CONFIG_SWAP
	392	if (unlikely(PageSwapCache(page)))
	393	mapping = &swapper_space;
	394	else
	395	#endif
	396	if ((unsigned long)mapping & PAGE_MAPPING_ANON)
	397	mapping = NULL;
	398	return mapping;
	399	}
	400
ca2b84cb	401	/* Tracepoints definitions. */
ca2b84cb EGM	402	EXPORT_TRACEPOINT_SYMBOL(kmalloc);
	403	EXPORT_TRACEPOINT_SYMBOL(kmem_cache_alloc);
	404	EXPORT_TRACEPOINT_SYMBOL(kmalloc_node);
	405	EXPORT_TRACEPOINT_SYMBOL(kmem_cache_alloc_node);
	406	EXPORT_TRACEPOINT_SYMBOL(kfree);
	407	EXPORT_TRACEPOINT_SYMBOL(kmem_cache_free);