Sparse Disk Device

Files
file	sparse-disk.h
	Sparse disk block device API.
file	sparse-disk.c
	Sparse disk block device implementation.

Data Structures
struct	rtems_sparse_disk_key
struct	rtems_sparse_disk

Typedefs
typedef struct rtems_sparse_disk	rtems_sparse_disk
typedef void(*	rtems_sparse_disk_delete_handler) (rtems_sparse_disk *sparse_disk)

Functions
rtems_status_code	rtems_sparse_disk_create_and_register (const char *device_file_name, uint32_t media_block_size, rtems_blkdev_bnum blocks_with_buffer, rtems_blkdev_bnum media_block_count, uint8_t fill_pattern)
	Creates and registers a sparse disk.
void	rtems_sparse_disk_free (rtems_sparse_disk *sparse_disk)
	Frees a sparse disk.
rtems_status_code	rtems_sparse_disk_register (const char *device_file_name, rtems_sparse_disk *sparse_disk, uint32_t media_block_size, rtems_blkdev_bnum blocks_with_buffer, rtems_blkdev_bnum media_block_count, uint8_t fill_pattern, rtems_sparse_disk_delete_handler sparse_disk_delete)
	Initializes and registers a sparse disk.

Detailed Description

Function Documentation

rtems_sparse_disk_create_and_register()

rtems_status_code rtems_sparse_disk_create_and_register	(	const char *	device_file_name,
		uint32_t	media_block_size,
		rtems_blkdev_bnum	blocks_with_buffer,
		rtems_blkdev_bnum	media_block_count,
		uint8_t	fill_pattern
	)

Creates and registers a sparse disk.

Parameters

[in]	device_file_name	The device file name path.
[in]	media_block_size	The media block size in bytes.
[in]	blocks_with_buffer	Blocks of the device with a buffer. Other blocks can store only fill pattern value bytes.
[in]	block_count	The media block count of the device. It is the sum of blocks with buffer and blocks that contain only fill pattern value bytes.
[in]	fill_pattern	The fill pattern specifies the byte value of blocks without a buffer. It is also the initial value for blocks with a buffer.

Return values

RTEMS_SUCCESSFUL	Successful operation.
RTEMS_INVALID_NUMBER	Media block size or media block count is not positive. The blocks with buffer count is greater than the media block count.
RTEMS_NO_MEMORY	Not enough memory.
RTEMS_TOO_MANY	Cannot create semaphore.
RTEMS_UNSATISFIED	Cannot create generic device node.

See also

rtems_sparse_disk_register().

rtems_sparse_disk_free()

void rtems_sparse_disk_free

(

rtems_sparse_disk *

sparse_disk

)

Frees a sparse disk.

Calls free() on the sparse disk pointer.

rtems_sparse_disk_register()

rtems_status_code rtems_sparse_disk_register	(	const char *	device_file_name,
		rtems_sparse_disk *	sparse_disk,
		uint32_t	media_block_size,
		rtems_blkdev_bnum	blocks_with_buffer,
		rtems_blkdev_bnum	media_block_count,
		uint8_t	fill_pattern,
		rtems_sparse_disk_delete_handler	sparse_disk_delete
	)

Initializes and registers a sparse disk.

This will create one semaphore for mutual exclusion.

Parameters

[in]	device_file_name	The device file name path.
[in,out]	sparse_disk	The sparse disk.
[in]	media_block_size	The media block size in bytes.
[in]	blocks_with_buffer	Blocks of the device with a buffer. Other blocks can store only fill pattern value bytes.
[in]	block_count	The media block count of the device. It is the sum of blocks with buffer and blocks that contain only fill pattern value bytes.
[in]	fill_pattern	The fill pattern specifies the byte value of blocks without a buffer. It is also the initial value for blocks with a buffer.
[in]	sparse_disk_delete	The sparse disk delete handler.

Return values

RTEMS_SUCCESSFUL	Successful operation.
RTEMS_INVALID_NUMBER	Media block size or media block count is not positive. The blocks with buffer count is greater than the media block count.
RTEMS_INVALID_ADDRESS	Invalid sparse disk address.
RTEMS_TOO_MANY	Cannot create semaphore.
RTEMS_UNSATISFIED	Cannot create generic device node.