This module provides functions to manage disk devices. More...

Collaboration diagram for Block Device Disk Management:

Files
file	diskdevs.h
	Block Device Disk Management API.

file	diskdevs-init.c
	Block Device Disk Management Initialize.

file	diskdevs.c
	Block device disk management implementation.

Data Structures
struct	rtems_blkdev_read_ahead
	Block device read-ahead control. More...

struct	rtems_blkdev_stats
	Block device statistics. More...

struct	rtems_disk_device
	Description of a disk device (logical and physical disks). More...

Macros
#define	RTEMS_DISK_READ_AHEAD_NO_TRIGGER ((rtems_blkdev_bnum) -1)
	Trigger value to disable further read-ahead requests.

Typedefs
typedef uint32_t	rtems_blkdev_bnum
	Block device block index type.

typedef int(*	rtems_block_device_ioctl) (rtems_disk_device dd, uint32_t req, void argp)
	Block device IO control handler type.

Disk Device Maintainance
rtems_status_code	rtems_disk_create_phys (dev_t dev, uint32_t block_size, rtems_blkdev_bnum block_count, rtems_block_device_ioctl handler, void driver_data, const char name)
	Creates a physical disk with device identifier dev. More...

rtems_status_code	rtems_disk_create_log (dev_t dev, dev_t phys, rtems_blkdev_bnum block_begin, rtems_blkdev_bnum block_count, const char *name)
	Creates a logical disk with device identifier dev. More...

rtems_status_code	rtems_disk_delete (dev_t dev)
	Deletes a physical or logical disk device with identifier dev. More...

rtems_disk_device *	rtems_disk_obtain (dev_t dev)
	Returns the disk device descriptor for the device identifier dev. More...

rtems_status_code	rtems_disk_release (rtems_disk_device *dd)
	Releases the disk device descriptor dd. More...

Disk Management
rtems_status_code	rtems_disk_io_initialize (void)
	Initializes the disk device management. More...

rtems_status_code	rtems_disk_io_done (void)
	Releases all resources allocated for disk device management. More...

Detailed Description

This module provides functions to manage disk devices.

A disk is a set of blocks which are identified by a consecutive set of non-negative integers starting at zero. There are also logical disks which contain a subset of consecutive disk blocks. The logical disks are used to represent the partitions of a disk. The disk devices are accessed via the block device buffer module.

Function Documentation

◆ rtems_disk_create_log()

rtems_status_code rtems_disk_create_log	(	dev_t	dev,
		dev_t	phys,
		rtems_blkdev_bnum	block_begin,
		rtems_blkdev_bnum	block_count,
		const char *	name
	)

Creates a logical disk with device identifier dev.

A logical disk manages a subset of consecutive blocks contained in the physical disk with identifier phys. The start block index of the logical disk device is block_begin. The block count of the logcal disk will be block_count. The blocks must be within the range of blocks managed by the associated physical disk device. A device node will be registered in the file system with absolute path name, if name is not NULL. The block size and IO control handler are inherited by the physical disk.

Return values

RTEMS_SUCCESSFUL	Successful operation.
RTEMS_NOT_CONFIGURED	Cannot lock disk device operation mutex.
RTEMS_INVALID_ID	Specified physical disk identifier does not correspond to a physical disk.
RTEMS_INVALID_NUMBER	Begin block or block count are out of range.
RTEMS_NO_MEMORY	Not enough memory.
RTEMS_RESOURCE_IN_USE	Disk device descriptor for logical disk identifier is already in use.
RTEMS_UNSATISFIED	Cannot create device node.

References RTEMS_SUCCESSFUL.

◆ rtems_disk_create_phys()

rtems_status_code rtems_disk_create_phys	(	dev_t	dev,
		uint32_t	block_size,
		rtems_blkdev_bnum	block_count,
		rtems_block_device_ioctl	handler,
		void *	driver_data,
		const char *	name
	)

Creates a physical disk with device identifier dev.

The block size block_size must be positive. The disk will have block_count blocks. The block index starts with zero. The associated disk device driver will be invoked via the IO control handler handler. A device node will be registered in the file system with absolute path name, if name is not NULL. This function is usually invoked from a block device driver during initialization when a physical device is detected in the system. The device driver provides an IO control handler to allow block device operations.

Return values

RTEMS_SUCCESSFUL	Successful operation.
RTEMS_NOT_CONFIGURED	Cannot lock disk device operation mutex.
RTEMS_INVALID_ADDRESS	IO control handler is `NULL`.
RTEMS_INVALID_NUMBER	Block size is invalid.
RTEMS_NO_MEMORY	Not enough memory.
RTEMS_RESOURCE_IN_USE	Disk device descriptor is already in use.
RTEMS_UNSATISFIED	Cannot create device node.

References RTEMS_INVALID_ADDRESS, and RTEMS_SUCCESSFUL.

◆ rtems_disk_delete()

rtems_status_code rtems_disk_delete ( dev_t dev )

Deletes a physical or logical disk device with identifier dev.

Marks the disk device as deleted. When a physical disk device is deleted, all corresponding logical disk devices will marked as deleted too. Disks that are marked as deleted and have a usage counter of zero will be deleted. The corresponding device nodes will be removed from the file system. In case of a physical disk deletion the IO control handler will be invoked with a RTEMS_BLKIO_DELETED request. Disks that are still in use will be deleted upon release.

Return values

RTEMS_SUCCESSFUL	Successful operation.
RTEMS_NOT_CONFIGURED	Cannot lock disk device operation mutex.
RTEMS_INVALID_ID	No disk for specified device identifier.

References RTEMS_SUCCESSFUL.

Referenced by rtems_disk_release().

◆ rtems_disk_io_done()

rtems_status_code rtems_disk_io_done ( void )

Releases all resources allocated for disk device management.

There is no protection against concurrent access. If parts of the system are still in use the behaviour is undefined.

Return values

RTEMS_SUCCESSFUL Successful operation.

◆ rtems_disk_io_initialize()

rtems_status_code rtems_disk_io_initialize ( void )

Initializes the disk device management.

This functions returns successful if the disk device management is already initialized. There is no protection against concurrent access.

Return values

RTEMS_SUCCESSFUL	Successful initialization.
RTEMS_NO_MEMORY	Not enough memory or no semaphore available.
RTEMS_UNSATISFIED	Block device buffer initialization failed.

References RTEMS_SUCCESSFUL.

◆ rtems_disk_obtain()

rtems_disk_device* rtems_disk_obtain ( dev_t dev )

Returns the disk device descriptor for the device identifier dev.

Increments usage counter by one. You should release the disk device descriptor with rtems_disk_release().

Returns: Pointer to the disk device descriptor or NULL if no corresponding disk exists.

References rtems_interrupt_lock_acquire, and RTEMS_SUCCESSFUL.

◆ rtems_disk_release()

rtems_status_code rtems_disk_release ( rtems_disk_device * dd )

Releases the disk device descriptor dd.

Decrements usage counter by one.

Return values

RTEMS_SUCCESSFUL Successful operation.

References rtems_disk_device::deleted, rtems_disk_device::dev, rtems_disk_delete(), rtems_interrupt_lock_acquire, rtems_interrupt_lock_release, RTEMS_SUCCESSFUL, and rtems_disk_device::uses.

Files

Data Structures

Macros

Typedefs

Disk Device Maintainance

Disk Management

Detailed Description

Function Documentation

◆ rtems_disk_create_log()

◆ rtems_disk_create_phys()

◆ rtems_disk_delete()

◆ rtems_disk_io_done()

◆ rtems_disk_io_initialize()

◆ rtems_disk_obtain()

◆ rtems_disk_release()