Memory Blocks

Memory allocation and pools. More...

Files
file	mem.h
	pipewire/mem.h

Data Structures
struct	pw_mempool
	A memory pool is a collection of pw_memblocks. More...
struct	pw_memblock
	Memory block structure. More...
struct	pw_memmap
	a mapped region of a pw_memblock More...
struct	pw_mempool_events
struct	pw_map_range
	parameters to map a memory range More...
struct	pw_memchunk

Enumerations
enum	pw_memblock_flags {   PW_MEMBLOCK_FLAG_NONE = 0 , PW_MEMBLOCK_FLAG_READABLE = (1 << 0) , PW_MEMBLOCK_FLAG_WRITABLE = (1 << 1) , PW_MEMBLOCK_FLAG_SEAL = (1 << 2) ,   PW_MEMBLOCK_FLAG_MAP = (1 << 3) , PW_MEMBLOCK_FLAG_DONT_CLOSE = (1 << 4) , PW_MEMBLOCK_FLAG_DONT_NOTIFY = (1 << 5) , PW_MEMBLOCK_FLAG_UNMAPPABLE = (1 << 6) ,   PW_MEMBLOCK_FLAG_READWRITE = PW_MEMBLOCK_FLAG_READABLE | PW_MEMBLOCK_FLAG_WRITABLE }
	Flags passed to pw_mempool_alloc() More...
enum	pw_memmap_flags {   PW_MEMMAP_FLAG_NONE = 0 , PW_MEMMAP_FLAG_READ = (1 << 0) , PW_MEMMAP_FLAG_WRITE = (1 << 1) , PW_MEMMAP_FLAG_TWICE = (1 << 2) ,   PW_MEMMAP_FLAG_PRIVATE = (1 << 3) , PW_MEMMAP_FLAG_LOCKED = (1 << 4) , PW_MEMMAP_FLAG_READWRITE = PW_MEMMAP_FLAG_READ | PW_MEMMAP_FLAG_WRITE }

Macros
#define	PW_VERSION_MEMPOOL_EVENTS   0
#define	PW_MAP_RANGE_INIT   (struct pw_map_range){ 0, }

Functions
struct pw_mempool *	pw_mempool_new (struct pw_properties *props)
	Create a new memory pool.
void	pw_mempool_add_listener (struct pw_mempool *pool, struct spa_hook *listener, const struct pw_mempool_events *events, void *data)
	Listen for events.
void	pw_mempool_clear (struct pw_mempool *pool)
	Clear a pool.
void	pw_mempool_destroy (struct pw_mempool *pool)
	Clear and destroy a pool.
struct pw_memblock *	pw_mempool_alloc (struct pw_mempool *pool, enum pw_memblock_flags flags, uint32_t type, size_t size)
	Allocate a memory block from the pool.
struct pw_memblock *	pw_mempool_import_block (struct pw_mempool *pool, struct pw_memblock *mem)
	Import a block from another pool.
struct pw_memblock *	pw_mempool_import (struct pw_mempool *pool, enum pw_memblock_flags flags, uint32_t type, int fd)
	Import an fd into the pool.
void	pw_memblock_free (struct pw_memblock *mem)
	Free a memblock regardless of the refcount and destroy all mappings.
static void	pw_memblock_unref (struct pw_memblock *mem)
	Unref a memblock.
int	pw_mempool_remove_id (struct pw_mempool *pool, uint32_t id)
	Remove a memblock for given id.
struct pw_memblock *	pw_mempool_find_ptr (struct pw_mempool *pool, const void *ptr)
	Find memblock for given ptr.
struct pw_memblock *	pw_mempool_find_id (struct pw_mempool *pool, uint32_t id)
	Find memblock for given id.
struct pw_memblock *	pw_mempool_find_fd (struct pw_mempool *pool, int fd)
	Find memblock for given fd.
struct pw_memmap *	pw_memblock_map (struct pw_memblock *block, enum pw_memmap_flags flags, uint32_t offset, uint32_t size, uint32_t tag[5])
	Map a region of a memory block.
struct pw_memmap *	pw_mempool_map_id (struct pw_mempool *pool, uint32_t id, enum pw_memmap_flags flags, uint32_t offset, uint32_t size, uint32_t tag[5])
	Map a region of a memory block with id.
struct pw_memmap *	pw_mempool_import_map (struct pw_mempool *pool, struct pw_mempool *other, void *data, uint32_t size, uint32_t tag[5])
struct pw_memmap *	pw_mempool_find_tag (struct pw_mempool *pool, uint32_t tag[5], size_t size)
	find a map with the given tag
int	pw_memmap_free (struct pw_memmap *map)
	Unmap a region.
static void	pw_map_range_init (struct pw_map_range *range, uint32_t offset, uint32_t size, uint32_t page_size)
	Calculate parameters to mmap() memory into range so that size bytes at offset can be mapped with mmap().

Detailed Description

Memory allocation and pools.

Enumeration Type Documentation

pw_memblock_flags

enum pw_memblock_flags

Flags passed to pw_mempool_alloc()

Enumerator
PW_MEMBLOCK_FLAG_NONE
PW_MEMBLOCK_FLAG_READABLE	memory is readable
PW_MEMBLOCK_FLAG_WRITABLE	memory is writable
PW_MEMBLOCK_FLAG_SEAL	seal the fd
PW_MEMBLOCK_FLAG_MAP	mmap the fd
PW_MEMBLOCK_FLAG_DONT_CLOSE	don't close fd
PW_MEMBLOCK_FLAG_DONT_NOTIFY	don't notify events
PW_MEMBLOCK_FLAG_UNMAPPABLE	the fd can not be mmapped
PW_MEMBLOCK_FLAG_READWRITE

pw_memmap_flags

enum pw_memmap_flags

Enumerator
PW_MEMMAP_FLAG_NONE
PW_MEMMAP_FLAG_READ	map in read mode
PW_MEMMAP_FLAG_WRITE	map in write mode
PW_MEMMAP_FLAG_TWICE	map the same area twice after each other, creating a circular ringbuffer
PW_MEMMAP_FLAG_PRIVATE	writes will be private
PW_MEMMAP_FLAG_LOCKED	lock the memory into RAM
PW_MEMMAP_FLAG_READWRITE

Macro Definition Documentation

PW_VERSION_MEMPOOL_EVENTS

#define PW_VERSION_MEMPOOL_EVENTS   0

PW_MAP_RANGE_INIT

#define PW_MAP_RANGE_INIT   (struct pw_map_range){ 0, }

Function Documentation

pw_mempool_new()

struct pw_mempool * pw_mempool_new

(

struct pw_properties *

props

)

Create a new memory pool.

pw_mempool_add_listener()

void pw_mempool_add_listener	(	struct pw_mempool *	pool,
		struct spa_hook *	listener,
		const struct pw_mempool_events *	events,
		void *	data )

Listen for events.

pw_mempool_clear()

void pw_mempool_clear

(

struct pw_mempool *

pool

)

Clear a pool.

pw_mempool_destroy()

void pw_mempool_destroy

(

struct pw_mempool *

pool

)

Clear and destroy a pool.

pw_mempool_alloc()

struct pw_memblock * pw_mempool_alloc	(	struct pw_mempool *	pool,
		enum pw_memblock_flags	flags,
		uint32_t	type,
		size_t	size )

Allocate a memory block from the pool.

Allocate a memory block from the pool.

Parameters

pool	the pool to use
flags	memblock flags
type	the requested memory type one of enum spa_data_type
size	size to allocate

Returns

a memblock structure or NULL with errno on error

pw_mempool_import_block()

struct pw_memblock * pw_mempool_import_block	(	struct pw_mempool *	pool,
		struct pw_memblock *	mem )

Import a block from another pool.

pw_mempool_import()

struct pw_memblock * pw_mempool_import	(	struct pw_mempool *	pool,
		enum pw_memblock_flags	flags,
		uint32_t	type,
		int	fd )

Import an fd into the pool.

pw_memblock_free()

void pw_memblock_free

(

struct pw_memblock *

block

)

Free a memblock regardless of the refcount and destroy all mappings.

Free a memblock regardless of the refcount and destroy all mappings.

Parameters

block

a memblock

pw_memblock_unref()

static void pw_memblock_unref ( struct pw_memblock * mem )

inlinestatic

Unref a memblock.

pw_mempool_remove_id()

int pw_mempool_remove_id	(	struct pw_mempool *	pool,
		uint32_t	id )

Remove a memblock for given id.

pw_mempool_find_ptr()

struct pw_memblock * pw_mempool_find_ptr	(	struct pw_mempool *	pool,
		const void *	ptr )

Find memblock for given ptr.

pw_mempool_find_id()

struct pw_memblock * pw_mempool_find_id	(	struct pw_mempool *	pool,
		uint32_t	id )

Find memblock for given id.

pw_mempool_find_fd()

struct pw_memblock * pw_mempool_find_fd	(	struct pw_mempool *	pool,
		int	fd )

Find memblock for given fd.

pw_memblock_map()

struct pw_memmap * pw_memblock_map	(	struct pw_memblock *	block,
		enum pw_memmap_flags	flags,
		uint32_t	offset,
		uint32_t	size,
		uint32_t	tag[5] )

Map a region of a memory block.

pw_mempool_map_id()

struct pw_memmap * pw_mempool_map_id	(	struct pw_mempool *	pool,
		uint32_t	id,
		enum pw_memmap_flags	flags,
		uint32_t	offset,
		uint32_t	size,
		uint32_t	tag[5] )

Map a region of a memory block with id.

pw_mempool_import_map()

struct pw_memmap * pw_mempool_import_map	(	struct pw_mempool *	pool,
		struct pw_mempool *	other,
		void *	data,
		uint32_t	size,
		uint32_t	tag[5] )

pw_mempool_find_tag()

struct pw_memmap * pw_mempool_find_tag	(	struct pw_mempool *	pool,
		uint32_t	tag[5],
		size_t	size )

find a map with the given tag

pw_memmap_free()

int pw_memmap_free

(

struct pw_memmap *

map

)

Unmap a region.

pw_map_range_init()

static void pw_map_range_init ( struct pw_map_range * range, uint32_t offset, uint32_t size, uint32_t page_size )

inlinestatic

Calculate parameters to mmap() memory into range so that size bytes at offset can be mapped with mmap().