page_aligned.cpp File Reference

#include "precompiled.h"
#include "lib/allocators/page_aligned.h"
#include "lib/alignment.h"
#include "lib/sysdep/cpu.h"

Go to the source code of this file.

Macros
#define	MAP_ANONYMOUS   MAP_ANON

Functions
static Status	StatusFromMap (void *ret)
Status	mem_Reserve (size_t size, u8 **pp)
Status	mem_Release (u8 *p, size_t size)
Status	mem_Commit (u8 *p, size_t size, int prot)
Status	mem_Decommit (u8 *p, size_t size)
Status	mem_Protect (u8 *p, size_t size, int prot)
void *	page_aligned_alloc (size_t size)
	allocate memory aligned to the system page size. More...
void	page_aligned_free (void *p, size_t size)
	free a previously allocated page-aligned region. More...

Variables
static const int	mmap_flags = MAP_PRIVATE|MAP_ANONYMOUS

Macro Definition Documentation

#define MAP_ANONYMOUS   MAP_ANON

Definition at line 44 of file page_aligned.cpp.

Function Documentation

Status mem_Commit	(	u8 *	p,
		size_t	size,
		int	prot
	)

Definition at line 65 of file page_aligned.cpp.

Status mem_Decommit	(	u8 *	p,
		size_t	size
	)

Definition at line 76 of file page_aligned.cpp.

Status mem_Protect	(	u8 *	p,
		size_t	size,
		int	prot
	)

Definition at line 83 of file page_aligned.cpp.

Status mem_Release	(	u8 *	p,
		size_t	size
	)

Definition at line 57 of file page_aligned.cpp.

Status mem_Reserve	(	size_t	size,
		u8 **	pp
	)

Definition at line 49 of file page_aligned.cpp.

void* page_aligned_alloc

(

size_t

unaligned_size

)

allocate memory aligned to the system page size.

this is useful for file_cache_alloc, which uses this allocator to get sector-aligned (hopefully; see sys_max_sector_size) IO buffers.

note that this allocator is stateless and very little error checking can be performed.

the memory is initially writable and you can use mprotect to set other access permissions if desired.

Parameters

unaligned_size

minimum size [bytes] to allocate.

Returns

page-aligned and -padded memory or 0 on error / out of memory.

Definition at line 95 of file page_aligned.cpp.

void page_aligned_free	(	void *	p,
		size_t	unaligned_size
	)

free a previously allocated page-aligned region.

Parameters

p	Exact value returned from page_aligned_alloc
unaligned_size	Exact value passed to page_aligned_alloc

Definition at line 105 of file page_aligned.cpp.

static Status StatusFromMap ( void *  ret )

inlinestatic

Definition at line 32 of file page_aligned.cpp.

Variable Documentation

const int mmap_flags = MAP_PRIVATE|MAP_ANONYMOUS

static

Definition at line 47 of file page_aligned.cpp.