rtl-allocator.h File Reference

RTEMS Run-Time Linker Allocator. More...

#include <stdbool.h>
#include "rtl-indirect-ptr.h"

Go to the source code of this file.

Data Structures
struct	rtems_rtl_alloc_data

Macros
#define	RTEMS_RTL_ALLOC_TAGS   ((size_t) (RTEMS_RTL_ALLOC_READ_EXEC + 1))

Typedefs
typedef enum rtems_rtl_alloc_tags	rtems_rtl_alloc_tag
typedef enum rtems_rtl_alloc_cmd	rtems_rtl_alloc_cmd
typedef void(*	rtems_rtl_allocator) (rtems_rtl_alloc_cmd cmd, rtems_rtl_alloc_tag tag, void **address, size_t size)
typedef struct rtems_rtl_alloc_data	rtems_rtl_alloc_data

Enumerations
enum	rtems_rtl_alloc_tags {   RTEMS_RTL_ALLOC_OBJECT , RTEMS_RTL_ALLOC_SYMBOL , RTEMS_RTL_ALLOC_EXTERNAL , RTEMS_RTL_ALLOC_READ ,   RTEMS_RTL_ALLOC_READ_WRITE , RTEMS_RTL_ALLOC_READ_EXEC }
enum	rtems_rtl_alloc_cmd {   RTEMS_RTL_ALLOC_NEW , RTEMS_RTL_ALLOC_DEL , RTEMS_RTL_ALLOC_RESIZE , RTEMS_RTL_ALLOC_LOCK ,   RTEMS_RTL_ALLOC_UNLOCK , RTEMS_RTL_ALLOC_WR_ENABLE , RTEMS_RTL_ALLOC_WR_DISABLE }

Functions
void	rtems_rtl_alloc_initialise (rtems_rtl_alloc_data *data)
void *	rtems_rtl_alloc_new (rtems_rtl_alloc_tag tag, size_t size, bool zero)
void	rtems_rtl_alloc_del (rtems_rtl_alloc_tag tag, void *address)
void *	rtems_rtl_alloc_resize (rtems_rtl_alloc_tag tag, void *address, size_t size, bool zero)
void	rtems_rtl_alloc_lock (void)
void	rtems_rtl_alloc_unlock (void)
void	rtems_rtl_alloc_wr_enable (rtems_rtl_alloc_tag tag, void *address)
void	rtems_rtl_alloc_wr_disable (rtems_rtl_alloc_tag tag, void *address)
rtems_rtl_allocator	rtems_rtl_alloc_hook (rtems_rtl_allocator handler)
void	rtems_rtl_alloc_indirect_new (rtems_rtl_alloc_tag tag, rtems_rtl_ptr *handle, size_t size)
void	rtems_rtl_alloc_indirect_del (rtems_rtl_alloc_tag tag, rtems_rtl_ptr *handle)
rtems_rtl_alloc_tag	rtems_rtl_alloc_text_tag (void)
rtems_rtl_alloc_tag	rtems_rtl_alloc_const_tag (void)
rtems_rtl_alloc_tag	rtems_rtl_alloc_eh_tag (void)
rtems_rtl_alloc_tag	rtems_rtl_alloc_data_tag (void)
rtems_rtl_alloc_tag	rtems_rtl_alloc_bss_tag (void)
bool	rtems_rtl_alloc_module_new (void **text_base, size_t text_size, void **const_base, size_t const_size, void **eh_base, size_t eh_size, void **data_base, size_t data_size, void **bss_base, size_t bss_size)
bool	rtems_rtl_alloc_module_resize (void **text_base, size_t text_size, void **const_base, size_t const_size, void **eh_base, size_t eh_size, void **data_base, size_t data_size, void **bss_base, size_t bss_size)
void	rtems_rtl_alloc_module_del (void **text_base, void **const_base, void **eh_base, void **data_base, void **bss_base)

Detailed Description

RTEMS Run-Time Linker Allocator.

Macro Definition Documentation

RTEMS_RTL_ALLOC_TAGS

#define RTEMS_RTL_ALLOC_TAGS   ((size_t) (RTEMS_RTL_ALLOC_READ_EXEC + 1))

The number of tags.

Typedef Documentation

rtems_rtl_alloc_cmd

typedef enum rtems_rtl_alloc_cmd rtems_rtl_alloc_cmd

The allocator command type.

rtems_rtl_alloc_tag

typedef enum rtems_rtl_alloc_tags rtems_rtl_alloc_tag

The allocator tag type.

rtems_rtl_allocator

typedef void(* rtems_rtl_allocator) (rtems_rtl_alloc_cmd cmd, rtems_rtl_alloc_tag tag, void **address, size_t size)

Allocator handler handles all RTL allocations. It can be hooked and overridded for customised allocation schemes or memory maps.

Parameters

allocation	The request command.
tag	The type of allocation request.
address	Pointer to the memory address. If an allocation the value is unspecific on entry and the allocated address or NULL on exit. The NULL value means the allocation failed. If a delete or free request the memory address is the block to free. A free request of NULL is silently ignored.
size	The size of the allocation if an allocation request and not used if deleting or freeing a previous allocation.

Enumeration Type Documentation

rtems_rtl_alloc_cmd

enum rtems_rtl_alloc_cmd

Define the allocation command the loader requires.

Enumerator
RTEMS_RTL_ALLOC_NEW	Allocate new memory.
RTEMS_RTL_ALLOC_DEL	Delete allocated memory.
RTEMS_RTL_ALLOC_RESIZE	Resize allocated memory.
RTEMS_RTL_ALLOC_LOCK	Lock the allocator.
RTEMS_RTL_ALLOC_UNLOCK	Unlock the allocator.
RTEMS_RTL_ALLOC_WR_ENABLE	Enable writes to the memory.
RTEMS_RTL_ALLOC_WR_DISABLE	Disable writes to the memory.

rtems_rtl_alloc_tags

enum rtems_rtl_alloc_tags

Define the types of allocation the loader requires.

Note

It is best to use the object tag for general memory allocation and to leave the tags with specific access properties to the module data

Enumerator
RTEMS_RTL_ALLOC_OBJECT	A generic memory object.
RTEMS_RTL_ALLOC_SYMBOL	Memory used for symbols.
RTEMS_RTL_ALLOC_EXTERNAL	Memory used for external symbols.
RTEMS_RTL_ALLOC_READ	The memory is read only.
RTEMS_RTL_ALLOC_READ_WRITE	The memory is read and write.
RTEMS_RTL_ALLOC_READ_EXEC	The memory is read and executable.

Function Documentation

rtems_rtl_alloc_bss_tag()

rtems_rtl_alloc_tag rtems_rtl_alloc_bss_tag

(

void

)

Return the default tag for bss sections.

Returns

The bss tag.

rtems_rtl_alloc_const_tag()

rtems_rtl_alloc_tag rtems_rtl_alloc_const_tag

(

void

)

Return the default tag for const sections.

Returns

The const tag.

rtems_rtl_alloc_data_tag()

rtems_rtl_alloc_tag rtems_rtl_alloc_data_tag

(

void

)

Return the default tag for data sections.

Returns

The data tag.

rtems_rtl_alloc_del()

void rtems_rtl_alloc_del	(	rtems_rtl_alloc_tag	tag,
		void *	address
	)

The Runtime Loader allocator delete deletes allocated memory.

Parameters

tag	The type of allocation request.
address	The memory address to delete. A NULL is ignored.

rtems_rtl_alloc_eh_tag()

rtems_rtl_alloc_tag rtems_rtl_alloc_eh_tag

(

void

)

Return the default tag for exception sections.

Returns

The eh tag.

rtems_rtl_alloc_hook()

rtems_rtl_allocator rtems_rtl_alloc_hook

(

rtems_rtl_allocator

handler

)

Hook the Runtime Loader allocatior. A handler can call the previous handler in the chain to use it for specific tags. The default handler uses the system heap. Do not unhook your handler if memory it allocates has not been returned.

Parameters

handler

The handler to use as the allocator.

Returns

rtems_rtl_alloc_handler The previous handler.

rtems_rtl_alloc_indirect_del()

void rtems_rtl_alloc_indirect_del	(	rtems_rtl_alloc_tag	tag,
		rtems_rtl_ptr *	handle
	)

Free memory from an indirect handle.

Parameters

tag	The type of allocation request.
handle	The handle to free the memory from.

rtems_rtl_alloc_indirect_new()

void rtems_rtl_alloc_indirect_new	(	rtems_rtl_alloc_tag	tag,
		rtems_rtl_ptr *	handle,
		size_t	size
	)

Allocate memory to an indirect handle.

Parameters

tag	The type of allocation request.
handle	The handle to allocate the memory to.
size	The size of the allocation.

rtems_rtl_alloc_initialise()

void rtems_rtl_alloc_initialise

(

rtems_rtl_alloc_data *

data

)

Initialise the allocate data.

Parameters

data	The data to initialise.

rtems_rtl_alloc_lock()

void rtems_rtl_alloc_lock

(

void

)

The Runtime Loader allocator lock. An allocator that depends on a separate allocation process, for example the heap, may need to be locked during loading of an object file to make sure the locality of the memory. This call be used to lock such an allocator. Allocator calls in this interface are protected by the RTL lock.

rtems_rtl_alloc_module_del()

void rtems_rtl_alloc_module_del	(	void **	text_base,
		void **	const_base,
		void **	eh_base,
		void **	data_base,
		void **	bss_base
	)

Free the memory allocated to a module.

Parameters

text_base	Pointer to the text base pointer.
const_base	Pointer to the const base pointer.
eh_base	Pointer to the eh base pointer.
data_base	Pointer to the data base pointer.
bss_base	Pointer to the bss base pointer.

rtems_rtl_alloc_module_new()

bool rtems_rtl_alloc_module_new	(	void **	text_base,
		size_t	text_size,
		void **	const_base,
		size_t	const_size,
		void **	eh_base,
		size_t	eh_size,
		void **	data_base,
		size_t	data_size,
		void **	bss_base,
		size_t	bss_size
	)

Allocate the memory for a module given the size of the text, const, data and bss sections. If any part of the allocation fails the no memory is allocated.

Parameters

text_base	Pointer to the text base pointer.
text_size	The size of the read/exec section.
const_base	Pointer to the const base pointer.
const_size	The size of the read only section.
eh_base	Pointer to the eh base pointer.
eh_size	The size of the eh section.
data_base	Pointer to the data base pointer.
data_size	The size of the read/write secton.
bss_base	Pointer to the bss base pointer.
bss_size	The size of the read/write.

Return values

true	The memory has been allocated.
false	The allocation of memory has failed.

rtems_rtl_alloc_module_resize()

bool rtems_rtl_alloc_module_resize	(	void **	text_base,
		size_t	text_size,
		void **	const_base,
		size_t	const_size,
		void **	eh_base,
		size_t	eh_size,
		void **	data_base,
		size_t	data_size,
		void **	bss_base,
		size_t	bss_size
	)

Resize the allocated memory for a module given the new size of the text, const, data and bss sections. If any part of the allocation fails the allocated is deleted.

Parameters

text_base	Pointer to the text base pointer.
text_size	The size of the read/exec section.
const_base	Pointer to the const base pointer.
const_size	The size of the read only section.
eh_base	Pointer to the eh base pointer.
eh_size	The size of the eh section.
data_base	Pointer to the data base pointer.
data_size	The size of the read/write secton.
bss_base	Pointer to the bss base pointer.
bss_size	The size of the read/write.

Return values

true	The memory has been allocated.
false	The allocation of memory has failed.

rtems_rtl_alloc_new()

void * rtems_rtl_alloc_new	(	rtems_rtl_alloc_tag	tag,
		size_t	size,
		bool	zero
	)

The Runtime Loader allocator new allocates new memory and optionally clear the memory if requested.

Parameters

tag	The type of allocation request.
size	The size of the allocation.
zero	If true the memory is cleared.

Returns

void* The memory address or NULL is not memory available.

rtems_rtl_alloc_resize()

void * rtems_rtl_alloc_resize	(	rtems_rtl_alloc_tag	tag,
		void *	address,
		size_t	size,
		bool	zero
	)

The Runtime Loader allocator resize resizes allocated memory.

This call resizes a previously allocated block of memory. If the provided address cannot be resized it is deleted and a new block is allocated and the contents of the existing memory is copied.

Parameters

tag	The type of allocation request.
address	The memory address to resize. A NULL is ignored.
size	The size of the allocation.
zero	If true the memory is cleared.

Returns

void* The memory address or NULL is not memory available.

rtems_rtl_alloc_text_tag()

rtems_rtl_alloc_tag rtems_rtl_alloc_text_tag

(

void

)

Return the default tag for text sections.

Returns

The text tag.

rtems_rtl_alloc_unlock()

void rtems_rtl_alloc_unlock

(

void

)

The Runtime Loader allocator unlock. An allocator that depends on a separate allocation process, for example the heap, may need to be locked during loading of an object file to make sure the locality of the memory. This call can be used to unlock such an allocator. Allocator calls in this interface are protected by the RTL lock.

rtems_rtl_alloc_wr_disable()

void rtems_rtl_alloc_wr_disable	(	rtems_rtl_alloc_tag	tag,
		void *	address
	)

The Runtime Loader allocator disable write on a bloc of allocated memory.

Parameters

tag	The type of allocation request. Must match the address.
address	The memory address to write disable. A NULL is ignored.

rtems_rtl_alloc_wr_enable()

void rtems_rtl_alloc_wr_enable	(	rtems_rtl_alloc_tag	tag,
		void *	address
	)

The Runtime Loader allocator enable write on a bloc of allocated memory.

Parameters

tag	The type of allocation request. Must match the address.
address	The memory address to write enable. A NULL is ignored.