reduce.h File Reference

SPDK block compression. More...

Data Structures
struct	spdk_reduce_vol_params
	Describes the parameters of an spdk_reduce_vol. More...
struct	spdk_reduce_vol_cb_args
struct	spdk_reduce_backing_io
struct	spdk_reduce_backing_dev

Macros
#define	REDUCE_MAX_IOVECS   33

Typedefs
typedef void(*	spdk_reduce_vol_op_complete) (void *ctx, int reduce_errno)
typedef void(*	spdk_reduce_vol_op_with_handle_complete) (void *ctx, struct spdk_reduce_vol *vol, int reduce_errno)
typedef void(*	spdk_reduce_dev_cpl) (void *cb_arg, int reduce_errno)
	Defines function type for callback functions called when backing_dev operations are complete.

Enumerations
enum	spdk_reduce_backing_io_type { SPDK_REDUCE_BACKING_IO_WRITE , SPDK_REDUCE_BACKING_IO_READ , SPDK_REDUCE_BACKING_IO_UNMAP }

Functions
const struct spdk_uuid *	spdk_reduce_vol_get_uuid (struct spdk_reduce_vol *vol)
	Get the UUID for a libreduce compressed volume.
void	spdk_reduce_vol_init (struct spdk_reduce_vol_params *params, struct spdk_reduce_backing_dev *backing_dev, const char *pm_file_dir, spdk_reduce_vol_op_with_handle_complete cb_fn, void *cb_arg)
	Initialize a new libreduce compressed volume.
void	spdk_reduce_vol_load (struct spdk_reduce_backing_dev *backing_dev, spdk_reduce_vol_op_with_handle_complete cb_fn, void *cb_arg)
	Load an existing libreduce compressed volume.
void	spdk_reduce_vol_unload (struct spdk_reduce_vol *vol, spdk_reduce_vol_op_complete cb_fn, void *cb_arg)
	Unload a previously initialized or loaded libreduce compressed volume.
void	spdk_reduce_vol_destroy (struct spdk_reduce_backing_dev *backing_dev, spdk_reduce_vol_op_complete cb_fn, void *cb_arg)
	Destroy an existing libreduce compressed volume.
void	spdk_reduce_vol_readv (struct spdk_reduce_vol *vol, struct iovec *iov, int iovcnt, uint64_t offset, uint64_t length, spdk_reduce_vol_op_complete cb_fn, void *cb_arg)
	Read data from a libreduce compressed volume.
void	spdk_reduce_vol_writev (struct spdk_reduce_vol *vol, struct iovec *iov, int iovcnt, uint64_t offset, uint64_t length, spdk_reduce_vol_op_complete cb_fn, void *cb_arg)
	Write data to a libreduce compressed volume.
const struct spdk_reduce_vol_params *	spdk_reduce_vol_get_params (struct spdk_reduce_vol *vol)
	Get the params structure for a libreduce compressed volume.
void	spdk_reduce_vol_print_info (struct spdk_reduce_vol *vol)
	Dump out key information for a libreduce compressed volume and its PMEM.
const char *	spdk_reduce_vol_get_pm_path (const struct spdk_reduce_vol *vol)
	Get the pm path for a libreduce compressed volume.

Detailed Description

SPDK block compression.

Typedef Documentation

spdk_reduce_dev_cpl

typedef void(* spdk_reduce_dev_cpl) (void *cb_arg, int reduce_errno)

Defines function type for callback functions called when backing_dev operations are complete.

Parameters

cb_arg	Callback argument
reduce_errno	Completion status of backing_dev operation Negative values indicate negated errno value 0 indicates successful readv/writev/unmap operation Positive value indicates successful compress/decompress operations; number indicates number of bytes written to destination iovs

Function Documentation

spdk_reduce_vol_destroy()

void spdk_reduce_vol_destroy	(	struct spdk_reduce_backing_dev *	backing_dev,
		spdk_reduce_vol_op_complete	cb_fn,
		void *	cb_arg )

Destroy an existing libreduce compressed volume.

This will zero the metadata region on the backing device and delete the associated pm metadata file. If the backing device does not contain a compressed volume, the cb_fn will be called with error status without modifying the backing device nor deleting a pm file.

Parameters

backing_dev	Structure describing the backing device containing the compressed volume.
cb_fn	Callback function to signal completion of the destruction process.
cb_arg	Argument to pass to the callback function.

spdk_reduce_vol_get_params()

const struct spdk_reduce_vol_params * spdk_reduce_vol_get_params

(

struct spdk_reduce_vol *

vol

)

Get the params structure for a libreduce compressed volume.

This function will populate the given params structure for a given volume.

Parameters

vol	Previously loaded or initialized compressed volume.

Returns

params structure for the compressed volume.

spdk_reduce_vol_get_pm_path()

const char * spdk_reduce_vol_get_pm_path

(

const struct spdk_reduce_vol *

vol

)

Get the pm path for a libreduce compressed volume.

Parameters

vol	Previously loaded or initialized compressed volume.

Returns

pm path for the compressed volume.

spdk_reduce_vol_get_uuid()

const struct spdk_uuid * spdk_reduce_vol_get_uuid

(

struct spdk_reduce_vol *

vol

)

Get the UUID for a libreduce compressed volume.

Parameters

vol	Previously loaded or initialized compressed volume.

Returns

UUID for the compressed volume.

spdk_reduce_vol_init()

void spdk_reduce_vol_init	(	struct spdk_reduce_vol_params *	params,
		struct spdk_reduce_backing_dev *	backing_dev,
		const char *	pm_file_dir,
		spdk_reduce_vol_op_with_handle_complete	cb_fn,
		void *	cb_arg )

Initialize a new libreduce compressed volume.

Parameters

params	Parameters for the new volume.
backing_dev	Structure describing the backing device to use for the new volume.
pm_file_dir	Directory to use for creation of the persistent memory file to use for the new volume. This function will append the UUID as the filename to create in this directory.
cb_fn	Callback function to signal completion of the initialization process.
cb_arg	Argument to pass to the callback function.

spdk_reduce_vol_load()

void spdk_reduce_vol_load	(	struct spdk_reduce_backing_dev *	backing_dev,
		spdk_reduce_vol_op_with_handle_complete	cb_fn,
		void *	cb_arg )

Load an existing libreduce compressed volume.

Parameters

backing_dev	Structure describing the backing device containing the compressed volume.
cb_fn	Callback function to signal completion of the loading process.
cb_arg	Argument to pass to the callback function.

spdk_reduce_vol_print_info()

void spdk_reduce_vol_print_info

(

struct spdk_reduce_vol *

vol

)

Dump out key information for a libreduce compressed volume and its PMEM.

This function will print key information for a given volume its PMEM.

Parameters

vol	Previously loaded or initialized compressed volume.

spdk_reduce_vol_readv()

void spdk_reduce_vol_readv	(	struct spdk_reduce_vol *	vol,
		struct iovec *	iov,
		int	iovcnt,
		uint64_t	offset,
		uint64_t	length,
		spdk_reduce_vol_op_complete	cb_fn,
		void *	cb_arg )

Read data from a libreduce compressed volume.

This function will only read from logical blocks on the comparessed volume that fall within the same chunk.

Parameters

vol	Volume to read data.
iov	iovec array describing the data to be read
iovcnt	Number of elements in the iovec array
offset	Offset (in logical blocks) to read the data on the compressed volume
length	Length (in logical blocks) of the data to read
cb_fn	Callback function to signal completion of the readv operation.
cb_arg	Argument to pass to the callback function.

spdk_reduce_vol_unload()

void spdk_reduce_vol_unload	(	struct spdk_reduce_vol *	vol,
		spdk_reduce_vol_op_complete	cb_fn,
		void *	cb_arg )

Unload a previously initialized or loaded libreduce compressed volume.

Parameters

vol	Volume to unload.
cb_fn	Callback function to signal completion of the unload process.
cb_arg	Argument to pass to the callback function.

spdk_reduce_vol_writev()

void spdk_reduce_vol_writev	(	struct spdk_reduce_vol *	vol,
		struct iovec *	iov,
		int	iovcnt,
		uint64_t	offset,
		uint64_t	length,
		spdk_reduce_vol_op_complete	cb_fn,
		void *	cb_arg )

Write data to a libreduce compressed volume.

This function will only write to logical blocks on the comparessed volume that fall within the same chunk.

Parameters

vol	Volume to write data.
iov	iovec array describing the data to be written
iovcnt	Number of elements in the iovec array
offset	Offset (in logical blocks) to write the data on the compressed volume
length	Length (in logical blocks) of the data to write
cb_fn	Callback function to signal completion of the writev operation.
cb_arg	Argument to pass to the callback function.