[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 <linux/swapops.h>
#include <linux/mman.h>
#include <linux/hugetlb.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;
}
#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));
	if (unlikely(PageSwapCache(page))) {
		swp_entry_t entry;

		entry.val = page_private(page);
		mapping = swap_address_space(entry);
	} else if ((unsigned long)mapping & PAGE_MAPPING_ANON)
		mapping = NULL;
	return mapping;
}

/*
 * Committed memory limit enforced when OVERCOMMIT_NEVER policy is used
 */
unsigned long vm_commit_limit(void)
{
	return ((totalram_pages - hugetlb_total_pages())
		* sysctl_overcommit_ratio / 100) + total_swap_pages;
}


/* 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>
33806f06	9	#include <linux/swapops.h>
00619bcc JM	10	#include <linux/mman.h>
	11	#include <linux/hugetlb.h>
	12
96840aa0	13	#include <asm/uaccess.h>
30992c97	14
6038def0 NK	15	#include "internal.h"
6038def0 NK	16
a8d154b0	17	#define CREATE_TRACE_POINTS
ad8d75ff	18	#include <trace/events/kmem.h>
a8d154b0	19
30992c97	20	/**
30992c97	21	* kstrdup - allocate space for and copy an existing string
30992c97 MM	22	* @s: the string to duplicate
	23	* @gfp: the GFP mask used in the kmalloc() call when allocating memory
	24	*/
	25	char kstrdup(const char s, gfp_t gfp)
	26	{
	27	size_t len;
	28	char *buf;
	29
	30	if (!s)
	31	return NULL;
	32
	33	len = strlen(s) + 1;
1d2c8eea	34	buf = kmalloc_track_caller(len, gfp);
30992c97 MM	35	if (buf)
	36	memcpy(buf, s, len);
	37	return buf;
	38	}
	39	EXPORT_SYMBOL(kstrdup);
96840aa0	40
1e66df3e JF	41	/**
	42	* kstrndup - allocate space for and copy an existing string
	43	* @s: the string to duplicate
	44	* @max: read at most @max chars from @s
	45	* @gfp: the GFP mask used in the kmalloc() call when allocating memory
	46	*/
	47	char kstrndup(const char s, size_t max, gfp_t gfp)
	48	{
	49	size_t len;
	50	char *buf;
	51
	52	if (!s)
	53	return NULL;
	54
	55	len = strnlen(s, max);
	56	buf = kmalloc_track_caller(len+1, gfp);
	57	if (buf) {
	58	memcpy(buf, s, len);
	59	buf[len] = '\0';
	60	}
	61	return buf;
	62	}
	63	EXPORT_SYMBOL(kstrndup);
	64
1a2f67b4 AD	65	/**
	66	* kmemdup - duplicate region of memory
	67	*
	68	* @src: memory region to duplicate
	69	* @len: memory region length
	70	* @gfp: GFP mask to use
	71	*/
	72	void kmemdup(const void src, size_t len, gfp_t gfp)
	73	{
	74	void *p;
	75
1d2c8eea	76	p = kmalloc_track_caller(len, gfp);
1a2f67b4 AD	77	if (p)
	78	memcpy(p, src, len);
	79	return p;
	80	}
	81	EXPORT_SYMBOL(kmemdup);
	82
610a77e0 LZ	83	/**
	84	* memdup_user - duplicate memory region from user space
	85	*
	86	* @src: source address in user space
	87	* @len: number of bytes to copy
	88	*
	89	* Returns an ERR_PTR() on failure.
	90	*/
	91	void memdup_user(const void __user src, size_t len)
	92	{
	93	void *p;
	94
	95	/*
	96	* Always use GFP_KERNEL, since copy_from_user() can sleep and
	97	* cause pagefault, which makes it pointless to use GFP_NOFS
	98	* or GFP_ATOMIC.
	99	*/
	100	p = kmalloc_track_caller(len, GFP_KERNEL);
	101	if (!p)
	102	return ERR_PTR(-ENOMEM);
	103
	104	if (copy_from_user(p, src, len)) {
	105	kfree(p);
	106	return ERR_PTR(-EFAULT);
	107	}
	108
	109	return p;
	110	}
	111	EXPORT_SYMBOL(memdup_user);
	112
e21827aa EG	113	static __always_inline void __do_krealloc(const void p, size_t new_size,
	114	gfp_t flags)
	115	{
	116	void *ret;
	117	size_t ks = 0;
	118
	119	if (p)
	120	ks = ksize(p);
	121
	122	if (ks >= new_size)
	123	return (void *)p;
	124
	125	ret = kmalloc_track_caller(new_size, flags);
	126	if (ret && p)
	127	memcpy(ret, p, ks);
	128
	129	return ret;
	130	}
	131
ef2ad80c	132	/**
93bc4e89	133	* __krealloc - like krealloc() but don't free @p.
ef2ad80c CL	134	* @p: object to reallocate memory for.
	135	* @new_size: how many bytes of memory are required.
	136	* @flags: the type of memory to allocate.
	137	*
93bc4e89 PE	138	* This function is like krealloc() except it never frees the originally
	139	* allocated buffer. Use this if you don't want to free the buffer immediately
	140	* like, for example, with RCU.
ef2ad80c	141	*/
93bc4e89	142	void __krealloc(const void p, size_t new_size, gfp_t flags)
ef2ad80c	143	{
93bc4e89	144	if (unlikely(!new_size))
6cb8f913	145	return ZERO_SIZE_PTR;
ef2ad80c	146
e21827aa	147	return __do_krealloc(p, new_size, flags);
ef8b4520	148
93bc4e89 PE	149	}
	150	EXPORT_SYMBOL(__krealloc);
	151
	152	/**
	153	* krealloc - reallocate memory. The contents will remain unchanged.
	154	* @p: object to reallocate memory for.
	155	* @new_size: how many bytes of memory are required.
	156	* @flags: the type of memory to allocate.
	157	*
	158	* The contents of the object pointed to are preserved up to the
	159	* lesser of the new and old sizes. If @p is %NULL, krealloc()
0db10c8e	160	* behaves exactly like kmalloc(). If @new_size is 0 and @p is not a
93bc4e89 PE	161	* %NULL pointer, the object pointed to is freed.
	162	*/
	163	void krealloc(const void p, size_t new_size, gfp_t flags)
	164	{
	165	void *ret;
	166
	167	if (unlikely(!new_size)) {
ef2ad80c	168	kfree(p);
93bc4e89	169	return ZERO_SIZE_PTR;
ef2ad80c	170	}
93bc4e89	171
e21827aa	172	ret = __do_krealloc(p, new_size, flags);
93bc4e89 PE	173	if (ret && p != ret)
	174	kfree(p);
	175
ef2ad80c CL	176	return ret;
	177	}
	178	EXPORT_SYMBOL(krealloc);
	179
3ef0e5ba JW	180	/**
	181	* kzfree - like kfree but zero memory
	182	* @p: object to free memory of
	183	*
	184	* The memory of the object @p points to is zeroed before freed.
	185	* If @p is %NULL, kzfree() does nothing.
a234bdc9 PE	186	*
	187	* Note: this function zeroes the whole allocated buffer which can be a good
	188	* deal bigger than the requested buffer size passed to kmalloc(). So be
	189	* careful when using this function in performance sensitive code.
3ef0e5ba JW	190	*/
	191	void kzfree(const void *p)
	192	{
	193	size_t ks;
	194	void mem = (void )p;
	195
	196	if (unlikely(ZERO_OR_NULL_PTR(mem)))
	197	return;
	198	ks = ksize(mem);
	199	memset(mem, 0, ks);
	200	kfree(mem);
	201	}
	202	EXPORT_SYMBOL(kzfree);
	203
96840aa0 DA	204	/*
96840aa0 DA	205	* strndup_user - duplicate an existing string from user space
96840aa0 DA	206	* @s: The string to duplicate
	207	* @n: Maximum number of bytes to copy, including the trailing NUL.
	208	*/
	209	char strndup_user(const char __user s, long n)
	210	{
	211	char *p;
	212	long length;
	213
	214	length = strnlen_user(s, n);
	215
	216	if (!length)
	217	return ERR_PTR(-EFAULT);
	218
	219	if (length > n)
	220	return ERR_PTR(-EINVAL);
	221
90d74045	222	p = memdup_user(s, length);
96840aa0	223
90d74045 JL	224	if (IS_ERR(p))
90d74045 JL	225	return p;
96840aa0 DA	226
	227	p[length - 1] = '\0';
	228
	229	return p;
	230	}
	231	EXPORT_SYMBOL(strndup_user);
16d69265	232
6038def0 NK	233	void __vma_link_list(struct mm_struct mm, struct vm_area_struct vma,
	234	struct vm_area_struct prev, struct rb_node rb_parent)
	235	{
	236	struct vm_area_struct *next;
	237
	238	vma->vm_prev = prev;
	239	if (prev) {
	240	next = prev->vm_next;
	241	prev->vm_next = vma;
	242	} else {
	243	mm->mmap = vma;
	244	if (rb_parent)
	245	next = rb_entry(rb_parent,
	246	struct vm_area_struct, vm_rb);
	247	else
	248	next = NULL;
	249	}
	250	vma->vm_next = next;
	251	if (next)
	252	next->vm_prev = vma;
	253	}
	254
b7643757 SP	255	/* Check if the vma is being used as a stack by this task */
	256	static int vm_is_stack_for_task(struct task_struct *t,
	257	struct vm_area_struct *vma)
	258	{
	259	return (vma->vm_start <= KSTK_ESP(t) && vma->vm_end >= KSTK_ESP(t));
	260	}
	261
	262	/*
	263	* Check if the vma is being used as a stack.
	264	* If is_group is non-zero, check in the entire thread group or else
	265	* just check in the current task. Returns the pid of the task that
	266	* the vma is stack for.
	267	*/
	268	pid_t vm_is_stack(struct task_struct *task,
	269	struct vm_area_struct *vma, int in_group)
	270	{
	271	pid_t ret = 0;
	272
	273	if (vm_is_stack_for_task(task, vma))
	274	return task->pid;
	275
	276	if (in_group) {
	277	struct task_struct *t;
	278	rcu_read_lock();
	279	if (!pid_alive(task))
	280	goto done;
	281
	282	t = task;
	283	do {
	284	if (vm_is_stack_for_task(t, vma)) {
	285	ret = t->pid;
	286	goto done;
	287	}
	288	} while_each_thread(task, t);
	289	done:
	290	rcu_read_unlock();
	291	}
	292
	293	return ret;
	294	}
	295
efc1a3b1	296	#if defined(CONFIG_MMU) && !defined(HAVE_ARCH_PICK_MMAP_LAYOUT)
16d69265 AM	297	void arch_pick_mmap_layout(struct mm_struct *mm)
	298	{
	299	mm->mmap_base = TASK_UNMAPPED_BASE;
	300	mm->get_unmapped_area = arch_get_unmapped_area;
16d69265 AM	301	}
16d69265 AM	302	#endif
912985dc	303
45888a0c XG	304	/*
	305	* Like get_user_pages_fast() except its IRQ-safe in that it won't fall
	306	* back to the regular GUP.
25985edc	307	* If the architecture not support this function, simply return with no
45888a0c XG	308	* page pinned
	309	*/
	310	int __attribute__((weak)) __get_user_pages_fast(unsigned long start,
	311	int nr_pages, int write, struct page **pages)
	312	{
	313	return 0;
	314	}
	315	EXPORT_SYMBOL_GPL(__get_user_pages_fast);
	316
9de100d0 AG	317	/**
	318	* get_user_pages_fast() - pin user pages in memory
	319	* @start: starting user address
	320	* @nr_pages: number of pages from start to pin
	321	* @write: whether pages will be written to
	322	* @pages: array that receives pointers to the pages pinned.
	323	* Should be at least nr_pages long.
	324	*
9de100d0 AG	325	* Returns number of pages pinned. This may be fewer than the number
	326	* requested. If nr_pages is 0 or negative, returns 0. If no pages
	327	* were pinned, returns -errno.
d2bf6be8 NP	328	*
	329	* get_user_pages_fast provides equivalent functionality to get_user_pages,
	330	* operating on current and current->mm, with force=0 and vma=NULL. However
	331	* unlike get_user_pages, it must be called without mmap_sem held.
	332	*
	333	* get_user_pages_fast may take mmap_sem and page table locks, so no
	334	* assumptions can be made about lack of locking. get_user_pages_fast is to be
	335	* implemented in a way that is advantageous (vs get_user_pages()) when the
	336	* user memory area is already faulted in and present in ptes. However if the
	337	* pages have to be faulted in, it may turn out to be slightly slower so
	338	* callers need to carefully consider what to use. On many architectures,
	339	* get_user_pages_fast simply falls back to get_user_pages.
9de100d0	340	*/
912985dc RR	341	int __attribute__((weak)) get_user_pages_fast(unsigned long start,
	342	int nr_pages, int write, struct page **pages)
	343	{
	344	struct mm_struct *mm = current->mm;
	345	int ret;
	346
	347	down_read(&mm->mmap_sem);
	348	ret = get_user_pages(current, mm, start, nr_pages,
	349	write, 0, pages, NULL);
	350	up_read(&mm->mmap_sem);
	351
	352	return ret;
	353	}
	354	EXPORT_SYMBOL_GPL(get_user_pages_fast);
ca2b84cb	355
eb36c587 AV	356	unsigned long vm_mmap_pgoff(struct file *file, unsigned long addr,
	357	unsigned long len, unsigned long prot,
	358	unsigned long flag, unsigned long pgoff)
	359	{
	360	unsigned long ret;
	361	struct mm_struct *mm = current->mm;
41badc15	362	unsigned long populate;
eb36c587 AV	363
	364	ret = security_mmap_file(file, prot, flag);
	365	if (!ret) {
	366	down_write(&mm->mmap_sem);
bebeb3d6 ML	367	ret = do_mmap_pgoff(file, addr, len, prot, flag, pgoff,
bebeb3d6 ML	368	&populate);
eb36c587	369	up_write(&mm->mmap_sem);
41badc15 ML	370	if (populate)
41badc15 ML	371	mm_populate(ret, populate);
eb36c587 AV	372	}
	373	return ret;
	374	}
	375
	376	unsigned long vm_mmap(struct file *file, unsigned long addr,
	377	unsigned long len, unsigned long prot,
	378	unsigned long flag, unsigned long offset)
	379	{
	380	if (unlikely(offset + PAGE_ALIGN(len) < offset))
	381	return -EINVAL;
	382	if (unlikely(offset & ~PAGE_MASK))
	383	return -EINVAL;
	384
	385	return vm_mmap_pgoff(file, addr, len, prot, flag, offset >> PAGE_SHIFT);
	386	}
	387	EXPORT_SYMBOL(vm_mmap);
	388
9800339b SL	389	struct address_space page_mapping(struct page page)
	390	{
	391	struct address_space *mapping = page->mapping;
	392
	393	VM_BUG_ON(PageSlab(page));
33806f06 SL	394	if (unlikely(PageSwapCache(page))) {
	395	swp_entry_t entry;
	396
	397	entry.val = page_private(page);
	398	mapping = swap_address_space(entry);
d2cf5ad6	399	} else if ((unsigned long)mapping & PAGE_MAPPING_ANON)
9800339b SL	400	mapping = NULL;
	401	return mapping;
	402	}
	403
00619bcc JM	404	/*
	405	* Committed memory limit enforced when OVERCOMMIT_NEVER policy is used
	406	*/
	407	unsigned long vm_commit_limit(void)
	408	{
	409	return ((totalram_pages - hugetlb_total_pages())
	410	* sysctl_overcommit_ratio / 100) + total_swap_pages;
	411	}
	412
	413
ca2b84cb	414	/* Tracepoints definitions. */
ca2b84cb EGM	415	EXPORT_TRACEPOINT_SYMBOL(kmalloc);
	416	EXPORT_TRACEPOINT_SYMBOL(kmem_cache_alloc);
	417	EXPORT_TRACEPOINT_SYMBOL(kmalloc_node);
	418	EXPORT_TRACEPOINT_SYMBOL(kmem_cache_alloc_node);
	419	EXPORT_TRACEPOINT_SYMBOL(kfree);
	420	EXPORT_TRACEPOINT_SYMBOL(kmem_cache_free);