Block device abstraction layer. More...

Data Structures
struct	spdk_bdev_media_event
	Media management event details. More...

struct	spdk_bdev_enable_histogram_opts
	Structure with optional enable histogram parameters. More...

struct	spdk_bdev_io_stat

struct	spdk_bdev_opts

union	spdk_bdev_nvme_ctratt
	Union for controller attributes field, to list whether bdev supports fdp etc. More...

union	spdk_bdev_nvme_cdw12
	Union for command dword 12, which by convention matches the NVMe command dword 12 definition. More...

union	spdk_bdev_nvme_cdw13
	Union for command dword 13, which by convention matches the NVMe command dword 13 definition. More...

struct	spdk_bdev_ext_io_opts
	Structure with optional IO request parameters. More...

struct	spdk_bdev_open_async_opts
	Structure with optional asynchronous bdev open parameters. More...

struct	spdk_bdev_io_wait_entry
	Structure to register a callback when an spdk_bdev_io becomes available. More...

Macros
#define	SPDK_BDEV_SMALL_BUF_MAX_SIZE 8192

#define	SPDK_BDEV_LARGE_BUF_MAX_SIZE (64 * 1024)

#define	SPDK_BDEV_MAX_INTERLEAVED_MD_SIZE (64)

#define	SPDK_BDEV_BUF_SIZE_WITH_MD(x) (((x) / 512) * (512 + SPDK_BDEV_MAX_INTERLEAVED_MD_SIZE))

Typedefs
typedef void(*	spdk_bdev_remove_cb_t) (void *remove_ctx)
	Block device remove callback.

typedef void(*	spdk_bdev_event_cb_t) (enum spdk_bdev_event_type type, struct spdk_bdev bdev, void event_ctx)
	Block device event callback.

typedef void(*	spdk_bdev_io_completion_cb) (struct spdk_bdev_io bdev_io, bool success, void cb_arg)
	Block device completion callback.

typedef void(*	spdk_bdev_wait_for_examine_cb) (void *arg)

typedef void(*	spdk_bdev_init_cb) (void *cb_arg, int rc)
	Block device initialization callback.

typedef void(*	spdk_bdev_fini_cb) (void *cb_arg)
	Block device finish callback.

typedef void(*	spdk_bdev_get_device_stat_cb) (struct spdk_bdev bdev, struct spdk_bdev_io_stat stat, void *cb_arg, int rc)

typedef void(*	spdk_bdev_io_timeout_cb) (void cb_arg, struct spdk_bdev_io bdev_io)
	Block device channel IO timeout callback.

typedef void(*	spdk_bdev_open_async_cb_t) (struct spdk_bdev_desc desc, int rc, void cb_arg)
	Block device asynchronous open callback.

typedef int(*	spdk_for_each_bdev_fn) (void ctx, struct spdk_bdev bdev)
	Callback function for spdk_for_each_bdev() and spdk_for_each_bdev_leaf().

typedef void(*	spdk_bdev_io_wait_cb) (void *cb_arg)
	Block device I/O wait callback.

typedef void(*	spdk_bdev_histogram_status_cb) (void *cb_arg, int status)

typedef void(*	spdk_bdev_histogram_data_cb) (void cb_arg, int status, struct spdk_histogram_data histogram)

typedef void(*	spdk_bdev_for_each_channel_msg) (struct spdk_bdev_channel_iter i, struct spdk_bdev bdev, struct spdk_io_channel ch, void ctx)
	Called on the appropriate thread for each channel associated with the given bdev.

typedef void(*	spdk_bdev_for_each_channel_done) (struct spdk_bdev bdev, void ctx, int status)
	spdk_bdev_for_each_channel() function's final callback with the given bdev.

Enumerations
enum	spdk_bdev_event_type { SPDK_BDEV_EVENT_REMOVE , SPDK_BDEV_EVENT_RESIZE , SPDK_BDEV_EVENT_MEDIA_MANAGEMENT }
	Asynchronous event type.

enum	spdk_bdev_status { SPDK_BDEV_STATUS_INVALID , SPDK_BDEV_STATUS_READY , SPDK_BDEV_STATUS_UNREGISTERING , SPDK_BDEV_STATUS_REMOVING }
	bdev status

enum	spdk_bdev_io_type { SPDK_BDEV_IO_TYPE_INVALID = 0 , SPDK_BDEV_IO_TYPE_READ , SPDK_BDEV_IO_TYPE_WRITE , SPDK_BDEV_IO_TYPE_UNMAP , SPDK_BDEV_IO_TYPE_FLUSH , SPDK_BDEV_IO_TYPE_RESET , SPDK_BDEV_IO_TYPE_NVME_ADMIN , SPDK_BDEV_IO_TYPE_NVME_IO , SPDK_BDEV_IO_TYPE_NVME_IO_MD , SPDK_BDEV_IO_TYPE_WRITE_ZEROES , SPDK_BDEV_IO_TYPE_ZCOPY , SPDK_BDEV_IO_TYPE_GET_ZONE_INFO , SPDK_BDEV_IO_TYPE_ZONE_MANAGEMENT , SPDK_BDEV_IO_TYPE_ZONE_APPEND , SPDK_BDEV_IO_TYPE_COMPARE , SPDK_BDEV_IO_TYPE_COMPARE_AND_WRITE , SPDK_BDEV_IO_TYPE_ABORT , SPDK_BDEV_IO_TYPE_SEEK_HOLE , SPDK_BDEV_IO_TYPE_SEEK_DATA , SPDK_BDEV_IO_TYPE_COPY , SPDK_BDEV_IO_TYPE_NVME_IOV_MD , SPDK_BDEV_NUM_IO_TYPES }
	bdev I/O type

enum	spdk_bdev_qos_rate_limit_type { SPDK_BDEV_QOS_RW_IOPS_RATE_LIMIT = 0 , SPDK_BDEV_QOS_RW_BPS_RATE_LIMIT , SPDK_BDEV_QOS_R_BPS_RATE_LIMIT , SPDK_BDEV_QOS_W_BPS_RATE_LIMIT , SPDK_BDEV_QOS_NUM_RATE_LIMIT_TYPES }
	bdev QoS rate limit type More...

Functions
	SPDK_STATIC_ASSERT (sizeof(struct spdk_bdev_enable_histogram_opts)==9, "Incorrect size")

	SPDK_STATIC_ASSERT (sizeof(struct spdk_bdev_opts)==32, "Incorrect size")

	SPDK_STATIC_ASSERT (sizeof(union spdk_bdev_nvme_ctratt)==4, "Incorrect size")

	SPDK_STATIC_ASSERT (sizeof(union spdk_bdev_nvme_cdw12)==4, "Incorrect size")

	SPDK_STATIC_ASSERT (sizeof(union spdk_bdev_nvme_cdw13)==4, "Incorrect size")

	SPDK_STATIC_ASSERT (sizeof(struct spdk_bdev_ext_io_opts)==52, "Incorrect size")

void	spdk_bdev_get_opts (struct spdk_bdev_opts *opts, size_t opts_size)
	Get the options for the bdev module.

int	spdk_bdev_set_opts (struct spdk_bdev_opts *opts)

int	spdk_bdev_wait_for_examine (spdk_bdev_wait_for_examine_cb cb_fn, void *cb_arg)
	Report when all bdevs finished the examine process.

int	spdk_bdev_examine (const char *name)
	Examine a block device explicitly.

void	spdk_bdev_initialize (spdk_bdev_init_cb cb_fn, void *cb_arg)
	Initialize block device modules.

void	spdk_bdev_finish (spdk_bdev_fini_cb cb_fn, void *cb_arg)
	Perform cleanup work to remove the registered block device modules.

void	spdk_bdev_subsystem_config_json (struct spdk_json_write_ctx *w)
	Get the full configuration options for the registered block device modules and created bdevs.

const char *	spdk_bdev_get_module_name (const struct spdk_bdev *bdev)
	Get block device module name.

struct spdk_bdev *	spdk_bdev_get_by_name (const char *bdev_name)
	Get block device by the block device name.

struct spdk_bdev *	spdk_bdev_first (void)
	Get the first registered block device.

struct spdk_bdev *	spdk_bdev_next (struct spdk_bdev *prev)
	Get the next registered block device.

struct spdk_bdev *	spdk_bdev_first_leaf (void)
	Get the first block device without virtual block devices on top.

struct spdk_bdev *	spdk_bdev_next_leaf (struct spdk_bdev *prev)
	Get the next block device without virtual block devices on top.

int	spdk_bdev_open_ext (const char bdev_name, bool write, spdk_bdev_event_cb_t event_cb, void event_ctx, struct spdk_bdev_desc **desc)
	Open a block device for I/O operations.

	SPDK_STATIC_ASSERT (sizeof(struct spdk_bdev_open_async_opts)==16, "Incorrect size")

int	spdk_bdev_open_async (const char bdev_name, bool write, spdk_bdev_event_cb_t event_cb, void event_ctx, struct spdk_bdev_open_async_opts opts, spdk_bdev_open_async_cb_t open_cb, void open_cb_arg)
	Open a block device for I/O operations asynchronously with options.

void	spdk_bdev_close (struct spdk_bdev_desc *desc)
	Close a previously opened block device.

int32_t	spdk_bdev_get_numa_id (struct spdk_bdev *bdev)
	Get the NUMA node ID for the specified bdev.

int	spdk_for_each_bdev (void *ctx, spdk_for_each_bdev_fn fn)
	Call the provided callback function for every registered block device.

int	spdk_for_each_bdev_leaf (void *ctx, spdk_for_each_bdev_fn fn)
	Call the provided callback function for every block device without virtual block devices on top.

struct spdk_bdev *	spdk_bdev_desc_get_bdev (struct spdk_bdev_desc *desc)
	Get the bdev associated with a bdev descriptor.

int	spdk_bdev_set_timeout (struct spdk_bdev_desc desc, uint64_t timeout_in_sec, spdk_bdev_io_timeout_cb cb_fn, void cb_arg)
	Set a time limit for the timeout IO of the bdev and timeout callback.

bool	spdk_bdev_io_type_supported (struct spdk_bdev *bdev, enum spdk_bdev_io_type io_type)
	Check whether the block device supports the I/O type.

const char *	spdk_bdev_get_io_type_name (enum spdk_bdev_io_type io_type)
	return the name of an IO type based on the io_type.

int	spdk_bdev_get_io_type (const char *io_type_string)
	Return the io_type based on the io_type_string.

int	spdk_bdev_dump_info_json (struct spdk_bdev bdev, struct spdk_json_write_ctx w)
	Output driver-specific information to a JSON stream.

const char *	spdk_bdev_get_name (const struct spdk_bdev *bdev)
	Get block device name.

const char *	spdk_bdev_get_product_name (const struct spdk_bdev *bdev)
	Get block device product name.

uint32_t	spdk_bdev_get_block_size (const struct spdk_bdev *bdev)
	Get block device logical block size.

uint32_t	spdk_bdev_get_write_unit_size (const struct spdk_bdev *bdev)
	Get the write unit size for this bdev.

uint64_t	spdk_bdev_get_num_blocks (const struct spdk_bdev *bdev)
	Get size of block device in logical blocks.

const char *	spdk_bdev_get_qos_rpc_type (enum spdk_bdev_qos_rate_limit_type type)
	Get the string of quality of service rate limit.

void	spdk_bdev_get_qos_rate_limits (struct spdk_bdev bdev, uint64_t limits)
	Get the quality of service rate limits on a bdev.

void	spdk_bdev_set_qos_rate_limits (struct spdk_bdev bdev, uint64_t limits, void(cb_fn)(void cb_arg, int status), void *cb_arg)
	Set the quality of service rate limits on a bdev.

size_t	spdk_bdev_get_buf_align (const struct spdk_bdev *bdev)
	Get minimum I/O buffer address alignment for a bdev.

uint32_t	spdk_bdev_get_optimal_io_boundary (const struct spdk_bdev *bdev)
	Get optimal I/O boundary for a bdev.

bool	spdk_bdev_has_write_cache (const struct spdk_bdev *bdev)
	Query whether block device has an enabled write cache.

const struct spdk_uuid *	spdk_bdev_get_uuid (const struct spdk_bdev *bdev)
	Get a bdev's UUID.

uint16_t	spdk_bdev_get_acwu (const struct spdk_bdev *bdev)
	Get block device atomic compare and write unit.

uint32_t	spdk_bdev_get_md_size (const struct spdk_bdev *bdev)
	Get block device metadata size.

bool	spdk_bdev_is_md_interleaved (const struct spdk_bdev *bdev)
	Query whether metadata is interleaved with block data or separated with block data.

bool	spdk_bdev_is_md_separate (const struct spdk_bdev *bdev)
	Query whether metadata is interleaved with block data or separated from block data.

bool	spdk_bdev_is_zoned (const struct spdk_bdev *bdev)
	Checks if bdev supports zoned namespace semantics.

uint32_t	spdk_bdev_get_data_block_size (const struct spdk_bdev *bdev)
	Get block device data block size.

uint32_t	spdk_bdev_get_physical_block_size (const struct spdk_bdev *bdev)
	Get block device physical block size.

enum spdk_dif_type	spdk_bdev_get_dif_type (const struct spdk_bdev *bdev)
	Get DIF type of the block device.

enum spdk_dif_pi_format	spdk_bdev_get_dif_pi_format (const struct spdk_bdev *bdev)
	Get DIF protection information format of the block device.

bool	spdk_bdev_is_dif_head_of_md (const struct spdk_bdev *bdev)
	Check whether DIF is set in the first 8/16 bytes or the last 8/16 bytes of metadata.

bool	spdk_bdev_is_dif_check_enabled (const struct spdk_bdev *bdev, enum spdk_dif_check_type check_type)
	Check whether the DIF check type is enabled.

uint32_t	spdk_bdev_get_max_copy (const struct spdk_bdev *bdev)
	Get block device max copy size.

uint64_t	spdk_bdev_get_qd (const struct spdk_bdev *bdev)
	Get the most recently measured queue depth from a bdev.

uint64_t	spdk_bdev_get_qd_sampling_period (const struct spdk_bdev *bdev)
	Get the queue depth polling period.

void	spdk_bdev_set_qd_sampling_period (struct spdk_bdev *bdev, uint64_t period)
	Enable or disable queue depth sampling for this bdev.

uint64_t	spdk_bdev_get_io_time (const struct spdk_bdev *bdev)
	Get the time spent processing IO for this device.

uint64_t	spdk_bdev_get_weighted_io_time (const struct spdk_bdev *bdev)
	Get the weighted IO processing time for this bdev.

struct spdk_io_channel *	spdk_bdev_get_io_channel (struct spdk_bdev_desc *desc)
	Obtain an I/O channel for the block device opened by the specified descriptor.

void *	spdk_bdev_get_module_ctx (struct spdk_bdev_desc *desc)
	Obtain a bdev module context for the block device opened by the specified descriptor.

int	spdk_bdev_seek_data (struct spdk_bdev_desc desc, struct spdk_io_channel ch, uint64_t offset_blocks, spdk_bdev_io_completion_cb cb, void *cb_arg)
	Submit a data seek request to the bdev on the given channel.

int	spdk_bdev_seek_hole (struct spdk_bdev_desc desc, struct spdk_io_channel ch, uint64_t offset_blocks, spdk_bdev_io_completion_cb cb, void *cb_arg)
	Submit a hole seek request to the bdev on the given channel.

int	spdk_bdev_read (struct spdk_bdev_desc desc, struct spdk_io_channel ch, void buf, uint64_t offset, uint64_t nbytes, spdk_bdev_io_completion_cb cb, void cb_arg)
	Submit a read request to the bdev on the given channel.

int	spdk_bdev_read_blocks (struct spdk_bdev_desc desc, struct spdk_io_channel ch, void buf, uint64_t offset_blocks, uint64_t num_blocks, spdk_bdev_io_completion_cb cb, void cb_arg)
	Submit a read request to the bdev on the given channel.

int	spdk_bdev_read_blocks_with_md (struct spdk_bdev_desc desc, struct spdk_io_channel ch, void buf, void md, uint64_t offset_blocks, uint64_t num_blocks, spdk_bdev_io_completion_cb cb, void *cb_arg)
	Submit a read request to the bdev on the given channel.

int	spdk_bdev_readv (struct spdk_bdev_desc desc, struct spdk_io_channel ch, struct iovec iov, int iovcnt, uint64_t offset, uint64_t nbytes, spdk_bdev_io_completion_cb cb, void cb_arg)
	Submit a read request to the bdev on the given channel.

int	spdk_bdev_readv_blocks (struct spdk_bdev_desc desc, struct spdk_io_channel ch, struct iovec iov, int iovcnt, uint64_t offset_blocks, uint64_t num_blocks, spdk_bdev_io_completion_cb cb, void cb_arg)
	Submit a read request to the bdev on the given channel.

int	spdk_bdev_readv_blocks_with_md (struct spdk_bdev_desc desc, struct spdk_io_channel ch, struct iovec iov, int iovcnt, void md, uint64_t offset_blocks, uint64_t num_blocks, spdk_bdev_io_completion_cb cb, void *cb_arg)
	Submit a read request to the bdev on the given channel.

int	spdk_bdev_readv_blocks_ext (struct spdk_bdev_desc desc, struct spdk_io_channel ch, struct iovec iov, int iovcnt, uint64_t offset_blocks, uint64_t num_blocks, spdk_bdev_io_completion_cb cb, void cb_arg, struct spdk_bdev_ext_io_opts *opts)
	Submit a read request to the bdev on the given channel.

int	spdk_bdev_write (struct spdk_bdev_desc desc, struct spdk_io_channel ch, void buf, uint64_t offset, uint64_t nbytes, spdk_bdev_io_completion_cb cb, void cb_arg)
	Submit a write request to the bdev on the given channel.

int	spdk_bdev_write_blocks (struct spdk_bdev_desc desc, struct spdk_io_channel ch, void buf, uint64_t offset_blocks, uint64_t num_blocks, spdk_bdev_io_completion_cb cb, void cb_arg)
	Submit a write request to the bdev on the given channel.

int	spdk_bdev_write_blocks_with_md (struct spdk_bdev_desc desc, struct spdk_io_channel ch, void buf, void md, uint64_t offset_blocks, uint64_t num_blocks, spdk_bdev_io_completion_cb cb, void *cb_arg)
	Submit a write request to the bdev on the given channel.

int	spdk_bdev_writev (struct spdk_bdev_desc desc, struct spdk_io_channel ch, struct iovec iov, int iovcnt, uint64_t offset, uint64_t len, spdk_bdev_io_completion_cb cb, void cb_arg)
	Submit a write request to the bdev on the given channel.

int	spdk_bdev_writev_blocks (struct spdk_bdev_desc desc, struct spdk_io_channel ch, struct iovec iov, int iovcnt, uint64_t offset_blocks, uint64_t num_blocks, spdk_bdev_io_completion_cb cb, void cb_arg)
	Submit a write request to the bdev on the given channel.

int	spdk_bdev_writev_blocks_with_md (struct spdk_bdev_desc desc, struct spdk_io_channel ch, struct iovec iov, int iovcnt, void md, uint64_t offset_blocks, uint64_t num_blocks, spdk_bdev_io_completion_cb cb, void *cb_arg)
	Submit a write request to the bdev on the given channel.

int	spdk_bdev_writev_blocks_ext (struct spdk_bdev_desc desc, struct spdk_io_channel ch, struct iovec iov, int iovcnt, uint64_t offset_blocks, uint64_t num_blocks, spdk_bdev_io_completion_cb cb, void cb_arg, struct spdk_bdev_ext_io_opts *opts)
	Submit a write request to the bdev on the given channel.

int	spdk_bdev_compare_blocks (struct spdk_bdev_desc desc, struct spdk_io_channel ch, void buf, uint64_t offset_blocks, uint64_t num_blocks, spdk_bdev_io_completion_cb cb, void cb_arg)
	Submit a compare request to the bdev on the given channel.

int	spdk_bdev_compare_blocks_with_md (struct spdk_bdev_desc desc, struct spdk_io_channel ch, void buf, void md, uint64_t offset_blocks, uint64_t num_blocks, spdk_bdev_io_completion_cb cb, void *cb_arg)
	Submit a compare request to the bdev on the given channel.

int	spdk_bdev_comparev_blocks (struct spdk_bdev_desc desc, struct spdk_io_channel ch, struct iovec iov, int iovcnt, uint64_t offset_blocks, uint64_t num_blocks, spdk_bdev_io_completion_cb cb, void cb_arg)
	Submit a compare request to the bdev on the given channel.

int	spdk_bdev_comparev_blocks_with_md (struct spdk_bdev_desc desc, struct spdk_io_channel ch, struct iovec iov, int iovcnt, void md, uint64_t offset_blocks, uint64_t num_blocks, spdk_bdev_io_completion_cb cb, void *cb_arg)
	Submit a compare request to the bdev on the given channel.

int	spdk_bdev_comparev_and_writev_blocks (struct spdk_bdev_desc desc, struct spdk_io_channel ch, struct iovec compare_iov, int compare_iovcnt, struct iovec write_iov, int write_iovcnt, uint64_t offset_blocks, uint64_t num_blocks, spdk_bdev_io_completion_cb cb, void *cb_arg)
	Submit an atomic compare-and-write request to the bdev on the given channel.

int	spdk_bdev_zcopy_start (struct spdk_bdev_desc desc, struct spdk_io_channel ch, struct iovec iov, int iovcnt, uint64_t offset_blocks, uint64_t num_blocks, bool populate, spdk_bdev_io_completion_cb cb, void cb_arg)
	Submit a request to acquire a data buffer that represents the given range of blocks.

int	spdk_bdev_zcopy_end (struct spdk_bdev_io bdev_io, bool commit, spdk_bdev_io_completion_cb cb, void cb_arg)
	Submit a request to release a data buffer representing a range of blocks.

int	spdk_bdev_write_zeroes (struct spdk_bdev_desc desc, struct spdk_io_channel ch, uint64_t offset, uint64_t len, spdk_bdev_io_completion_cb cb, void *cb_arg)
	Submit a write zeroes request to the bdev on the given channel.

int	spdk_bdev_write_zeroes_blocks (struct spdk_bdev_desc desc, struct spdk_io_channel ch, uint64_t offset_blocks, uint64_t num_blocks, spdk_bdev_io_completion_cb cb, void *cb_arg)
	Submit a write zeroes request to the bdev on the given channel.

int	spdk_bdev_unmap (struct spdk_bdev_desc desc, struct spdk_io_channel ch, uint64_t offset, uint64_t nbytes, spdk_bdev_io_completion_cb cb, void *cb_arg)
	Submit an unmap request to the block device.

int	spdk_bdev_unmap_blocks (struct spdk_bdev_desc desc, struct spdk_io_channel ch, uint64_t offset_blocks, uint64_t num_blocks, spdk_bdev_io_completion_cb cb, void *cb_arg)
	Submit an unmap request to the block device.

int	spdk_bdev_flush (struct spdk_bdev_desc desc, struct spdk_io_channel ch, uint64_t offset, uint64_t length, spdk_bdev_io_completion_cb cb, void *cb_arg)
	Submit a flush request to the bdev on the given channel.

int	spdk_bdev_flush_blocks (struct spdk_bdev_desc desc, struct spdk_io_channel ch, uint64_t offset_blocks, uint64_t num_blocks, spdk_bdev_io_completion_cb cb, void *cb_arg)
	Submit a flush request to the bdev on the given channel.

int	spdk_bdev_reset (struct spdk_bdev_desc desc, struct spdk_io_channel ch, spdk_bdev_io_completion_cb cb, void *cb_arg)
	Submit a reset request to the bdev on the given channel.

int	spdk_bdev_abort (struct spdk_bdev_desc desc, struct spdk_io_channel ch, void bio_cb_arg, spdk_bdev_io_completion_cb cb, void cb_arg)
	Submit abort requests to abort all I/Os which has bio_cb_arg as its callback context to the bdev on the given channel.

int	spdk_bdev_nvme_admin_passthru (struct spdk_bdev_desc desc, struct spdk_io_channel ch, const struct spdk_nvme_cmd cmd, void buf, size_t nbytes, spdk_bdev_io_completion_cb cb, void *cb_arg)
	Submit an NVMe Admin command to the bdev.

int	spdk_bdev_nvme_io_passthru (struct spdk_bdev_desc bdev_desc, struct spdk_io_channel ch, const struct spdk_nvme_cmd cmd, void buf, size_t nbytes, spdk_bdev_io_completion_cb cb, void *cb_arg)
	Submit an NVMe I/O command to the bdev.

int	spdk_bdev_nvme_io_passthru_md (struct spdk_bdev_desc bdev_desc, struct spdk_io_channel ch, const struct spdk_nvme_cmd cmd, void buf, size_t nbytes, void md_buf, size_t md_len, spdk_bdev_io_completion_cb cb, void cb_arg)
	Submit an NVMe I/O command to the bdev.

int	spdk_bdev_nvme_iov_passthru_md (struct spdk_bdev_desc desc, struct spdk_io_channel ch, const struct spdk_nvme_cmd cmd, struct iovec iov, int iovcnt, size_t nbytes, void md_buf, size_t md_len, spdk_bdev_io_completion_cb cb, void cb_arg)
	Submit an NVMe I/O command to the bdev.

int	spdk_bdev_copy_blocks (struct spdk_bdev_desc desc, struct spdk_io_channel ch, uint64_t dst_offset_blocks, uint64_t src_offset_blocks, uint64_t num_blocks, spdk_bdev_io_completion_cb cb, void *cb_arg)
	Submit a copy request to the block device.

void	spdk_bdev_free_io (struct spdk_bdev_io *bdev_io)
	Free an I/O request.

int	spdk_bdev_queue_io_wait (struct spdk_bdev bdev, struct spdk_io_channel ch, struct spdk_bdev_io_wait_entry *entry)
	Add an entry into the calling thread's queue to be notified when an spdk_bdev_io becomes available.

void	spdk_bdev_get_io_stat (struct spdk_bdev bdev, struct spdk_io_channel ch, struct spdk_bdev_io_stat *stat)
	Return I/O statistics for this channel.

void	spdk_bdev_get_device_stat (struct spdk_bdev bdev, struct spdk_bdev_io_stat stat, spdk_bdev_get_device_stat_cb cb, void *cb_arg)
	Return I/O statistics for this bdev.

void	spdk_bdev_io_get_nvme_status (const struct spdk_bdev_io bdev_io, uint32_t cdw0, int sct, int sc)
	Get the status of bdev_io as an NVMe status code and command specific completion queue value.

void	spdk_bdev_io_get_nvme_fused_status (const struct spdk_bdev_io bdev_io, uint32_t cdw0, int first_sct, int first_sc, int second_sct, int second_sc)
	Get the status of bdev_io as an NVMe status codes and command specific completion queue value for fused operations such as compare-and-write.

void	spdk_bdev_io_get_scsi_status (const struct spdk_bdev_io bdev_io, int sc, int sk, int asc, int *ascq)
	Get the status of bdev_io as a SCSI status code.

void	spdk_bdev_io_get_aio_status (const struct spdk_bdev_io bdev_io, int aio_result)
	Get the status of bdev_io as aio errno.

void	spdk_bdev_io_get_iovec (struct spdk_bdev_io bdev_io, struct iovec iovp, int iovcntp)
	Get the iovec describing the data buffer of a bdev_io.

void *	spdk_bdev_io_get_md_buf (struct spdk_bdev_io *bdev_io)
	Get metadata buffer.

void *	spdk_bdev_io_get_cb_arg (struct spdk_bdev_io *bdev_io)
	Get the callback argument of bdev_io to abort it by spdk_bdev_abort.

uint64_t	spdk_bdev_io_get_seek_offset (const struct spdk_bdev_io *bdev_io)
	Get the result of a previous seek function.

void	spdk_bdev_histogram_enable (struct spdk_bdev bdev, spdk_bdev_histogram_status_cb cb_fn, void cb_arg, bool enable)
	Enable or disable collecting histogram data on a bdev.

void	spdk_bdev_histogram_enable_ext (struct spdk_bdev bdev, spdk_bdev_histogram_status_cb cb_fn, void cb_arg, bool enable, struct spdk_bdev_enable_histogram_opts *opts)
	Enable or disable collecting histogram data on a bdev.

void	spdk_bdev_enable_histogram_opts_init (struct spdk_bdev_enable_histogram_opts *opts, size_t size)
	Initialize bdev enable histogram options structure.

void	spdk_bdev_histogram_get (struct spdk_bdev bdev, struct spdk_histogram_data histogram, spdk_bdev_histogram_data_cb cb_fn, void *cb_arg)
	Get aggregated histogram data from a bdev.

void	spdk_bdev_channel_get_histogram (struct spdk_io_channel ch, spdk_bdev_histogram_data_cb cb_fn, void cb_arg)
	Get histogram data of the specified channel for a bdev.

size_t	spdk_bdev_get_media_events (struct spdk_bdev_desc bdev_desc, struct spdk_bdev_media_event events, size_t max_events)
	Retrieves media events.

int	spdk_bdev_get_memory_domains (struct spdk_bdev bdev, struct spdk_memory_domain *domains, int array_size)
	Get SPDK memory domains used by the given bdev.

void	spdk_bdev_for_each_channel_continue (struct spdk_bdev_channel_iter *i, int status)
	Helper function to iterate the next channel for spdk_bdev_for_each_channel().

void	spdk_bdev_for_each_channel (struct spdk_bdev bdev, spdk_bdev_for_each_channel_msg fn, void ctx, spdk_bdev_for_each_channel_done cpl)
	Call 'fn' on each channel associated with the given bdev.

union spdk_bdev_nvme_ctratt	spdk_bdev_get_nvme_ctratt (struct spdk_bdev *bdev)
	Get controller attributes for the bdev.

Detailed Description

Block device abstraction layer.

Typedef Documentation

◆ spdk_bdev_event_cb_t

typedef void(* spdk_bdev_event_cb_t) (enum spdk_bdev_event_type type, struct spdk_bdev *bdev, void *event_ctx)

Block device event callback.

Parameters

type	Event type.
bdev	Block device that triggered event.
event_ctx	Context for the block device event.

◆ spdk_bdev_fini_cb

typedef void(* spdk_bdev_fini_cb) (void *cb_arg)

Block device finish callback.

Parameters

cb_arg Callback argument.

◆ spdk_bdev_for_each_channel_done

typedef void(* spdk_bdev_for_each_channel_done) (struct spdk_bdev *bdev, void *ctx, int status)

spdk_bdev_for_each_channel() function's final callback with the given bdev.

Parameters

bdev	Block device.
ctx	context of the bdev channel iterator.
status	0 if it completed successfully, or negative errno if it failed.

◆ spdk_bdev_for_each_channel_msg

typedef void(* spdk_bdev_for_each_channel_msg) (struct spdk_bdev_channel_iter *i, struct spdk_bdev *bdev, struct spdk_io_channel *ch, void *ctx)

Called on the appropriate thread for each channel associated with the given bdev.

Parameters

i	bdev channel iterator.
bdev	Block device.
ch	I/O channel.
ctx	context of the bdev channel iterator.

◆ spdk_bdev_init_cb

typedef void(* spdk_bdev_init_cb) (void *cb_arg, int rc)

Block device initialization callback.

Parameters

cb_arg	Callback argument.
rc	0 if block device initialized successfully or negative errno if it failed.

◆ spdk_bdev_io_completion_cb

typedef void(* spdk_bdev_io_completion_cb) (struct spdk_bdev_io *bdev_io, bool success, void *cb_arg)

Block device completion callback.

Parameters

bdev_io	Block device I/O that has completed.
success	True if I/O completed successfully or false if it failed; additional error information may be retrieved from bdev_io by calling spdk_bdev_io_get_nvme_status() or spdk_bdev_io_get_scsi_status().
cb_arg	Callback argument specified when bdev_io was submitted.

◆ spdk_bdev_io_timeout_cb

typedef void(* spdk_bdev_io_timeout_cb) (void *cb_arg, struct spdk_bdev_io *bdev_io)

Block device channel IO timeout callback.

Parameters

cb_arg	Callback argument
bdev_io	The IO cause the timeout

◆ spdk_bdev_io_wait_cb

typedef void(* spdk_bdev_io_wait_cb) (void *cb_arg)

Block device I/O wait callback.

Callback function to notify when an spdk_bdev_io structure is available to satisfy a call to one of the bdev I/O Submit Functions.

◆ spdk_bdev_open_async_cb_t

typedef void(* spdk_bdev_open_async_cb_t) (struct spdk_bdev_desc *desc, int rc, void *cb_arg)

Block device asynchronous open callback.

Parameters

desc	Output parameter for the descriptor when operation is successful.
rc	0 if block device is opened successfully or negated errno if failed.
cb_arg	Callback argument.

◆ spdk_bdev_remove_cb_t

typedef void(* spdk_bdev_remove_cb_t) (void *remove_ctx)

Block device remove callback.

Parameters

remove_ctx Context for the removed block device.

◆ spdk_for_each_bdev_fn

typedef int(* spdk_for_each_bdev_fn) (void *ctx, struct spdk_bdev *bdev)

Callback function for spdk_for_each_bdev() and spdk_for_each_bdev_leaf().

Parameters

ctx	Context passed to the callback.
bdev	Block device the callback handles.

Enumeration Type Documentation

◆ spdk_bdev_qos_rate_limit_type

enum spdk_bdev_qos_rate_limit_type

bdev QoS rate limit type

Enumerator
SPDK_BDEV_QOS_RW_IOPS_RATE_LIMIT	IOPS rate limit for both read and write.
SPDK_BDEV_QOS_RW_BPS_RATE_LIMIT	Byte per second rate limit for both read and write.
SPDK_BDEV_QOS_R_BPS_RATE_LIMIT	Byte per second rate limit for read only.
SPDK_BDEV_QOS_W_BPS_RATE_LIMIT	Byte per second rate limit for write only.
SPDK_BDEV_QOS_NUM_RATE_LIMIT_TYPES	Keep last.

Function Documentation

◆ spdk_bdev_channel_get_histogram()

void spdk_bdev_channel_get_histogram	(	struct spdk_io_channel *	ch,
		spdk_bdev_histogram_data_cb	cb_fn,
		void *	cb_arg )

Get histogram data of the specified channel for a bdev.

The histogram passed to cb_fn is only valid during the execution of cb_fn. Referencing the histogram after cb_fn returns is not supported and yields undetermined behavior.

Parameters

ch	IO channel of bdev.
cb_fn	Callback function to process the histogram of the channel.
cb_arg	Argument to pass to cb_fn.

◆ spdk_bdev_close()

void spdk_bdev_close ( struct spdk_bdev_desc * desc )

Close a previously opened block device.

Must be called on the same thread that the spdk_bdev_open_ext() was performed on.

Parameters

desc	Block device descriptor to close.

◆ spdk_bdev_desc_get_bdev()

struct spdk_bdev * spdk_bdev_desc_get_bdev ( struct spdk_bdev_desc * desc )

Get the bdev associated with a bdev descriptor.

Parameters

desc	Open block device descriptor

Returns: bdev associated with the descriptor

◆ spdk_bdev_dump_info_json()

int spdk_bdev_dump_info_json	(	struct spdk_bdev *	bdev,
		struct spdk_json_write_ctx *	w )

Output driver-specific information to a JSON stream.

The JSON write context will be initialized with an open object, so the bdev driver should write a name(based on the driver name) followed by a JSON value (most likely another nested object).

Parameters

bdev	Block device to query.
w	JSON write context. It will store the driver-specific configuration context.

Returns: 0 on success, negated errno on failure.

◆ spdk_bdev_enable_histogram_opts_init()

void spdk_bdev_enable_histogram_opts_init	(	struct spdk_bdev_enable_histogram_opts *	opts,
		size_t	size )

Initialize bdev enable histogram options structure.

Parameters

opts	The structure to initialize.
size	The size of *opts.

◆ spdk_bdev_examine()

int spdk_bdev_examine ( const char * name )

Examine a block device explicitly.

This function must be called from the SPDK app thread.

Parameters

name	the name or alias of the block device

Returns: 0 if block device was examined successfully, suitable errno value otherwise

◆ spdk_bdev_finish()

void spdk_bdev_finish	(	spdk_bdev_fini_cb	cb_fn,
		void *	cb_arg )

Perform cleanup work to remove the registered block device modules.

Parameters

cb_fn	Called when the removal is complete.
cb_arg	Argument passed to function cb_fn.

◆ spdk_bdev_first()

struct spdk_bdev * spdk_bdev_first ( void )

Get the first registered block device.

Returns: The first registered block device.

◆ spdk_bdev_first_leaf()

struct spdk_bdev * spdk_bdev_first_leaf ( void )

Get the first block device without virtual block devices on top.

This function only traverses over block devices which have no virtual block devices on top of them, then get the first one.

Returns: The first block device without virtual block devices on top.

◆ spdk_bdev_for_each_channel()

void spdk_bdev_for_each_channel	(	struct spdk_bdev *	bdev,
		spdk_bdev_for_each_channel_msg	fn,
		void *	ctx,
		spdk_bdev_for_each_channel_done	cpl )

Call 'fn' on each channel associated with the given bdev.

This happens asynchronously, so fn may be called after spdk_bdev_for_each_channel returns. 'fn' will be called for each channel serially, such that two calls to 'fn' will not overlap in time. After 'fn' has been called, call spdk_bdev_for_each_channel_continue() to continue iterating. Note that the spdk_bdev_for_each_channel_continue() function can be called asynchronously.

Parameters

bdev	'fn' will be called on each channel associated with this given bdev.
fn	Called on the appropriate thread for each channel associated with the given bdev.
ctx	Context for the caller.
cpl	Called on the thread that spdk_bdev_for_each_channel was initially called from when 'fn' has been called on each channel.

◆ spdk_bdev_for_each_channel_continue()

void spdk_bdev_for_each_channel_continue	(	struct spdk_bdev_channel_iter *	i,
		int	status )

Helper function to iterate the next channel for spdk_bdev_for_each_channel().

Parameters

i	bdev channel iterator.
status	Status for the bdev channel iterator; for non 0 status remaining iterations are terminated.

◆ spdk_bdev_free_io()

void spdk_bdev_free_io ( struct spdk_bdev_io * bdev_io )

Free an I/O request.

This should only be called after the completion callback for the I/O has been called and notifies the bdev layer that memory may now be released.

Parameters

bdev_io I/O request.

◆ spdk_bdev_get_acwu()

uint16_t spdk_bdev_get_acwu ( const struct spdk_bdev * bdev )

Get block device atomic compare and write unit.

Parameters

bdev	Block device to query.

Returns: Atomic compare and write unit for this bdev in blocks.

◆ spdk_bdev_get_block_size()

uint32_t spdk_bdev_get_block_size ( const struct spdk_bdev * bdev )

Get block device logical block size.

Parameters

bdev	Block device to query.

Returns: Size of logical block for this bdev in bytes.

◆ spdk_bdev_get_buf_align()

size_t spdk_bdev_get_buf_align ( const struct spdk_bdev * bdev )

Get minimum I/O buffer address alignment for a bdev.

Parameters

bdev	Block device to query.

Returns: Required alignment of I/O buffers in bytes.

◆ spdk_bdev_get_by_name()

struct spdk_bdev * spdk_bdev_get_by_name ( const char * bdev_name )

Get block device by the block device name.

Parameters

bdev_name The name of the block device.

Returns: Block device associated with the name or NULL if no block device with bdev_name is currently registered.

◆ spdk_bdev_get_data_block_size()

uint32_t spdk_bdev_get_data_block_size ( const struct spdk_bdev * bdev )

Get block device data block size.

Data block size is equal to block size if there is no metadata or metadata is separated with block data, or equal to block size minus metadata size if there is metadata and it is interleaved with block data.

Parameters

bdev	Block device to query.

Returns: Size of data block for this bdev in bytes.

◆ spdk_bdev_get_device_stat()

void spdk_bdev_get_device_stat	(	struct spdk_bdev *	bdev,
		struct spdk_bdev_io_stat *	stat,
		spdk_bdev_get_device_stat_cb	cb,
		void *	cb_arg )

Return I/O statistics for this bdev.

All the required information will be passed via the callback function.

Parameters

bdev	Block device to query.
stat	Structure for aggregating collected statistics. Passed as argument to cb.
cb	Called when this operation completes.
cb_arg	Argument passed to callback function.

◆ spdk_bdev_get_dif_pi_format()

enum spdk_dif_pi_format spdk_bdev_get_dif_pi_format ( const struct spdk_bdev * bdev )

Get DIF protection information format of the block device.

Note that this function is valid only if DIF type is not SPDK_DIF_DISABLE.

Parameters

bdev	Block device to query.

Returns: DIF protection information format of the block device.

◆ spdk_bdev_get_dif_type()

enum spdk_dif_type spdk_bdev_get_dif_type ( const struct spdk_bdev * bdev )

Get DIF type of the block device.

Parameters

bdev	Block device to query.

Returns: DIF type of the block device.

◆ spdk_bdev_get_io_channel()

struct spdk_io_channel * spdk_bdev_get_io_channel ( struct spdk_bdev_desc * desc )

Obtain an I/O channel for the block device opened by the specified descriptor.

I/O channels are bound to threads, so the resulting I/O channel may only be used from the thread it was originally obtained from.

Parameters

desc	Block device descriptor.

Returns: A handle to the I/O channel or NULL on failure.

◆ spdk_bdev_get_io_stat()

void spdk_bdev_get_io_stat	(	struct spdk_bdev *	bdev,
		struct spdk_io_channel *	ch,
		struct spdk_bdev_io_stat *	stat )

Return I/O statistics for this channel.

Parameters

bdev	Block device.
ch	I/O channel. Obtained by calling spdk_bdev_get_io_channel().
stat	The per-channel statistics.

◆ spdk_bdev_get_io_time()

uint64_t spdk_bdev_get_io_time ( const struct spdk_bdev * bdev )

Get the time spent processing IO for this device.

This value is dependent upon the queue depth sampling period and is incremented at sampling time by the sampling period only if the measured queue depth is greater than 0.

The disk utilization can be calculated by the following formula: disk_util = (io_time_2 - io_time_1) / elapsed_time. The user is responsible for tracking the elapsed time between two measurements.

Parameters

bdev	Block device to query.

Returns: The io time for this device in microseconds.

◆ spdk_bdev_get_io_type()

int spdk_bdev_get_io_type ( const char * io_type_string )

Return the io_type based on the io_type_string.

Parameters

io_type_string Name of the IO type as a null-terminated string.

Returns: io_type The specific I/O type like read, write, flush, unmap etc. This will map to enum spdk_bdev_io_type.

◆ spdk_bdev_get_io_type_name()

const char * spdk_bdev_get_io_type_name ( enum spdk_bdev_io_type io_type )

return the name of an IO type based on the io_type.

Parameters

io_type The specific I/O type like read, write, flush, unmap.

Returns: Name of the IO type as a null-terminated string.

◆ spdk_bdev_get_max_copy()

uint32_t spdk_bdev_get_max_copy ( const struct spdk_bdev * bdev )

Get block device max copy size.

Parameters

bdev	Block device to query.

Returns: Max copy size for this bdev in blocks. 0 means unlimited.

◆ spdk_bdev_get_md_size()

uint32_t spdk_bdev_get_md_size ( const struct spdk_bdev * bdev )

Get block device metadata size.

Parameters

bdev	Block device to query.

Returns: Size of metadata for this bdev in bytes.

◆ spdk_bdev_get_media_events()

size_t spdk_bdev_get_media_events	(	struct spdk_bdev_desc *	bdev_desc,
		struct spdk_bdev_media_event *	events,
		size_t	max_events )

Retrieves media events.

Can only be called from the context of SPDK_BDEV_EVENT_MEDIA_MANAGEMENT event callback. These events are sent by devices exposing raw access to the physical medium (e.g. Open Channel SSD).

Parameters

bdev_desc	Block device descriptor
events	Array of media management event descriptors
max_events	Size of the events array

Returns: number of events retrieved

◆ spdk_bdev_get_memory_domains()

int spdk_bdev_get_memory_domains	(	struct spdk_bdev *	bdev,
		struct spdk_memory_domain **	domains,
		int	array_size )

Get SPDK memory domains used by the given bdev.

If bdev reports that it uses memory domains that means that it can work with data buffers located in those memory domains.

The user can call this function with domains set to NULL and array_size set to 0 to get the number of memory domains used by bdev

Parameters

bdev	Block device
domains	Pointer to an array of memory domains to be filled by this function. The user should allocate big enough array to keep all memory domains used by bdev and all underlying bdevs
array_size	size of domains array

Returns: the number of entries in domains array or negated errno. If returned value is bigger than array_size passed by the user then the user should increase the size of domains array and call this function again. There is no guarantees that the content of domains array is valid in that case. -EINVAL if input parameters were invalid

◆ spdk_bdev_get_module_ctx()

void * spdk_bdev_get_module_ctx ( struct spdk_bdev_desc * desc )

Obtain a bdev module context for the block device opened by the specified descriptor.

Parameters

desc	Block device descriptor.

Returns: A bdev module context or NULL on failure.

◆ spdk_bdev_get_module_name()

const char * spdk_bdev_get_module_name ( const struct spdk_bdev * bdev )

Get block device module name.

Parameters

bdev	Block device to query.

Returns: Name of bdev module as a null-terminated string.

◆ spdk_bdev_get_name()

const char * spdk_bdev_get_name ( const struct spdk_bdev * bdev )

Get block device name.

Parameters

bdev	Block device to query.

Returns: Name of bdev as a null-terminated string.

◆ spdk_bdev_get_num_blocks()

uint64_t spdk_bdev_get_num_blocks ( const struct spdk_bdev * bdev )

Get size of block device in logical blocks.

Parameters

bdev	Block device to query.

Returns: Size of bdev in logical blocks.

Logical blocks are numbered from 0 to spdk_bdev_get_num_blocks(bdev) - 1, inclusive.

◆ spdk_bdev_get_numa_id()

int32_t spdk_bdev_get_numa_id ( struct spdk_bdev * bdev )

Get the NUMA node ID for the specified bdev.

Parameters

bdev	Block device to get the NUMA node ID for

Returns: NUMA node ID for the bdev, SPDK_ENV_NODE_ID_ANY if the ID ID is unknown.

◆ spdk_bdev_get_nvme_ctratt()

union spdk_bdev_nvme_ctratt spdk_bdev_get_nvme_ctratt ( struct spdk_bdev * bdev )

Get controller attributes for the bdev.

Parameters

bdev	Block device to query.

Returns: controller attributes for the bdev.

◆ spdk_bdev_get_optimal_io_boundary()

uint32_t spdk_bdev_get_optimal_io_boundary ( const struct spdk_bdev * bdev )

Get optimal I/O boundary for a bdev.

Parameters

bdev	Block device to query.

Returns: Optimal I/O boundary in blocks that should not be crossed for best performance, or 0 if no optimal boundary is reported.

◆ spdk_bdev_get_opts()

void spdk_bdev_get_opts	(	struct spdk_bdev_opts *	opts,
		size_t	opts_size )

Get the options for the bdev module.

Parameters

opts	Output parameter for options.
opts_size	sizeof(*opts)

◆ spdk_bdev_get_physical_block_size()

uint32_t spdk_bdev_get_physical_block_size ( const struct spdk_bdev * bdev )

Get block device physical block size.

Parameters

bdev	Block device to query.

Returns: Size of physical block size for this bdev in bytes.

◆ spdk_bdev_get_product_name()

const char * spdk_bdev_get_product_name ( const struct spdk_bdev * bdev )

Get block device product name.

Parameters

bdev	Block device to query.

Returns: Product name of bdev as a null-terminated string.

◆ spdk_bdev_get_qd()

uint64_t spdk_bdev_get_qd ( const struct spdk_bdev * bdev )

Get the most recently measured queue depth from a bdev.

The reported queue depth is the aggregate of outstanding I/O across all open channels associated with this bdev.

Parameters

bdev	Block device to query.

Returns: The most recent queue depth measurement for the bdev. If tracking is not enabled, the function will return UINT64_MAX It is also possible to receive UINT64_MAX after enabling tracking but before the first period has expired.

◆ spdk_bdev_get_qd_sampling_period()

uint64_t spdk_bdev_get_qd_sampling_period ( const struct spdk_bdev * bdev )

Get the queue depth polling period.

The return value of this function is only valid if the bdev's queue depth tracking status is set to true.

Parameters

bdev	Block device to query.

Returns: The period at which this bdev's gueue depth is being refreshed.

◆ spdk_bdev_get_qos_rate_limits()

void spdk_bdev_get_qos_rate_limits	(	struct spdk_bdev *	bdev,
		uint64_t *	limits )

Get the quality of service rate limits on a bdev.

Parameters

bdev	Block device to query.
limits	Pointer to the QoS rate limits array which holding the limits.

The limits are ordered based on the spdk_bdev_qos_rate_limit_type enum.

◆ spdk_bdev_get_qos_rpc_type()

const char * spdk_bdev_get_qos_rpc_type ( enum spdk_bdev_qos_rate_limit_type type )

Get the string of quality of service rate limit.

Parameters

type	Type of rate limit to query.

Returns: String of QoS type.

◆ spdk_bdev_get_uuid()

const struct spdk_uuid * spdk_bdev_get_uuid ( const struct spdk_bdev * bdev )

Get a bdev's UUID.

Parameters

bdev	Block device to query.

Returns: Pointer to UUID.

All bdevs will have a UUID, but not all UUIDs will be persistent across application runs.

◆ spdk_bdev_get_weighted_io_time()

uint64_t spdk_bdev_get_weighted_io_time ( const struct spdk_bdev * bdev )

Get the weighted IO processing time for this bdev.

This value is dependent upon the queue depth sampling period and is equal to the time spent reading from or writing to a device times the measured queue depth during each sampling period.

The average queue depth can be calculated by the following formula: queue_depth = (weighted_io_time_2 - weighted_io_time_1) / elapsed_time. The user is responsible for tracking the elapsed time between two measurements.

Parameters

bdev	Block device to query.

Returns: The weighted io time for this device in microseconds.

◆ spdk_bdev_get_write_unit_size()

uint32_t spdk_bdev_get_write_unit_size ( const struct spdk_bdev * bdev )

Get the write unit size for this bdev.

Write unit size is required number of logical blocks to perform write operation on block device.

Unit of write unit size is logical block and the minimum of write unit size is one. Write operations must be multiple of write unit size.

Parameters

bdev	Block device to query.

Returns: The write unit size in logical blocks.

◆ spdk_bdev_has_write_cache()

bool spdk_bdev_has_write_cache ( const struct spdk_bdev * bdev )

Query whether block device has an enabled write cache.

Parameters

bdev	Block device to query.

Returns: true if block device has a volatile write cache enabled.

If this function returns true, written data may not be persistent until a flush command is issued.

◆ spdk_bdev_histogram_enable()

void spdk_bdev_histogram_enable	(	struct spdk_bdev *	bdev,
		spdk_bdev_histogram_status_cb	cb_fn,
		void *	cb_arg,
		bool	enable )

Enable or disable collecting histogram data on a bdev.

Parameters

bdev	Block device.
cb_fn	Callback function to be called when histograms are enabled.
cb_arg	Argument to pass to cb_fn.
enable	Enable/disable flag

◆ spdk_bdev_histogram_enable_ext()

void spdk_bdev_histogram_enable_ext	(	struct spdk_bdev *	bdev,
		spdk_bdev_histogram_status_cb	cb_fn,
		void *	cb_arg,
		bool	enable,
		struct spdk_bdev_enable_histogram_opts *	opts )

Enable or disable collecting histogram data on a bdev.

This differs from spdk_bdev_histogram_enable by allowing Optional structure with extended enable histogram options.

Parameters

bdev	Block device.
cb_fn	Callback function to be called when histograms are enabled.
cb_arg	Argument to pass to cb_fn.
enable	Enable/disable flag
opts	Optional structure with extended enable histogram options. `size` member of this structure is used for ABI compatibility and must be set to sizeof(struct spdk_bdev_enable_histogram_opts).

◆ spdk_bdev_histogram_get()

void spdk_bdev_histogram_get	(	struct spdk_bdev *	bdev,
		struct spdk_histogram_data *	histogram,
		spdk_bdev_histogram_data_cb	cb_fn,
		void *	cb_arg )

Get aggregated histogram data from a bdev.

Callback provides merged histogram for specified bdev.

Parameters

bdev	Block device.
histogram	Histogram for aggregated data
cb_fn	Callback function to be called with data collected on bdev.
cb_arg	Argument to pass to cb_fn.

◆ spdk_bdev_initialize()

void spdk_bdev_initialize	(	spdk_bdev_init_cb	cb_fn,
		void *	cb_arg )

Initialize block device modules.

Parameters

cb_fn	Called when the initialization is complete.
cb_arg	Argument passed to function cb_fn.

◆ spdk_bdev_io_get_aio_status()

void spdk_bdev_io_get_aio_status	(	const struct spdk_bdev_io *	bdev_io,
		int *	aio_result )

Get the status of bdev_io as aio errno.

Parameters

bdev_io	I/O to get the status from.
aio_result	Negative errno returned from AIO.

◆ spdk_bdev_io_get_cb_arg()

void * spdk_bdev_io_get_cb_arg ( struct spdk_bdev_io * bdev_io )

Get the callback argument of bdev_io to abort it by spdk_bdev_abort.

Parameters

bdev_io I/O to get the callback argument from.

Returns: Callback argument of bdev_io.

◆ spdk_bdev_io_get_iovec()

void spdk_bdev_io_get_iovec	(	struct spdk_bdev_io *	bdev_io,
		struct iovec **	iovp,
		int *	iovcntp )

Get the iovec describing the data buffer of a bdev_io.

Parameters

bdev_io	I/O to describe with iovec.
iovp	Pointer to be filled with iovec.
iovcntp	Pointer to be filled with number of iovec entries.

◆ spdk_bdev_io_get_md_buf()

void * spdk_bdev_io_get_md_buf ( struct spdk_bdev_io * bdev_io )

Get metadata buffer.

Only makes sense if the IO uses separate buffer for metadata transfer.

Parameters

bdev_io I/O to retrieve the buffer from.

Returns: Pointer to metadata buffer, NULL if the IO doesn't use separate buffer for metadata transfer.

◆ spdk_bdev_io_get_nvme_fused_status()

void spdk_bdev_io_get_nvme_fused_status	(	const struct spdk_bdev_io *	bdev_io,
		uint32_t *	cdw0,
		int *	first_sct,
		int *	first_sc,
		int *	second_sct,
		int *	second_sc )

Get the status of bdev_io as an NVMe status codes and command specific completion queue value for fused operations such as compare-and-write.

Parameters

bdev_io	I/O to get the status from.
cdw0	Command specific completion queue value
first_sct	Status Code Type return value for the first operation, as defined by the NVMe specification.
first_sc	Status Code return value for the first operation, as defined by the NVMe specification.
second_sct	Status Code Type return value for the second operation, as defined by the NVMe specification.
second_sc	Status Code return value for the second operation, as defined by the NVMe specification.

◆ spdk_bdev_io_get_nvme_status()

void spdk_bdev_io_get_nvme_status	(	const struct spdk_bdev_io *	bdev_io,
		uint32_t *	cdw0,
		int *	sct,
		int *	sc )

Get the status of bdev_io as an NVMe status code and command specific completion queue value.

Parameters

bdev_io	I/O to get the status from.
cdw0	Command specific completion queue value
sct	Status Code Type return value, as defined by the NVMe specification.
sc	Status Code return value, as defined by the NVMe specification.

◆ spdk_bdev_io_get_scsi_status()

void spdk_bdev_io_get_scsi_status	(	const struct spdk_bdev_io *	bdev_io,
		int *	sc,
		int *	sk,
		int *	asc,
		int *	ascq )

Get the status of bdev_io as a SCSI status code.

Parameters

bdev_io	I/O to get the status from.
sc	SCSI Status Code.
sk	SCSI Sense Key.
asc	SCSI Additional Sense Code.
ascq	SCSI Additional Sense Code Qualifier.

◆ spdk_bdev_io_get_seek_offset()

uint64_t spdk_bdev_io_get_seek_offset ( const struct spdk_bdev_io * bdev_io )

Get the result of a previous seek function.

After calling spdk_bdev_seek_data or spdk_bdev_seek_hole, call this function to retrieve the offset of next allocated data or next unallocated hole.

Parameters

bdev_io I/O to get the status from.

Returns: data/hole offset in blocks or UINT64_MAX if not found

◆ spdk_bdev_io_type_supported()

bool spdk_bdev_io_type_supported	(	struct spdk_bdev *	bdev,
		enum spdk_bdev_io_type	io_type )

Check whether the block device supports the I/O type.

Parameters

bdev	Block device to check.
io_type	The specific I/O type like read, write, flush, unmap.

Returns: true if support, false otherwise.

◆ spdk_bdev_is_dif_check_enabled()

bool spdk_bdev_is_dif_check_enabled	(	const struct spdk_bdev *	bdev,
		enum spdk_dif_check_type	check_type )

Check whether the DIF check type is enabled.

Parameters

bdev	Block device to query.
check_type	The specific DIF check type.

Returns: true if enabled, false otherwise.

◆ spdk_bdev_is_dif_head_of_md()

bool spdk_bdev_is_dif_head_of_md ( const struct spdk_bdev * bdev )

Check whether DIF is set in the first 8/16 bytes or the last 8/16 bytes of metadata.

Parameters

bdev	Block device to query.

Returns: true if DIF is set in the first 8/16 bytes of metadata, or false if DIF is set in the last 8/16 bytes of metadata.

Note that this function is valid only if DIF type is not SPDK_DIF_DISABLE.

◆ spdk_bdev_is_md_interleaved()

bool spdk_bdev_is_md_interleaved ( const struct spdk_bdev * bdev )

Query whether metadata is interleaved with block data or separated with block data.

Parameters

bdev	Block device to query.

Returns: true if metadata is interleaved with block data or false if metadata is separated with block data.

Note this function is valid only if there is metadata.

◆ spdk_bdev_is_md_separate()

bool spdk_bdev_is_md_separate ( const struct spdk_bdev * bdev )

Query whether metadata is interleaved with block data or separated from block data.

Parameters

bdev	Block device to query.

Returns: true if metadata is separated from block data, false otherwise.

Note this function is valid only if there is metadata.

◆ spdk_bdev_is_zoned()

bool spdk_bdev_is_zoned ( const struct spdk_bdev * bdev )

Checks if bdev supports zoned namespace semantics.

Parameters

bdev	Block device to query.

Returns: true if device supports zoned namespace semantics.

◆ spdk_bdev_next()

struct spdk_bdev * spdk_bdev_next ( struct spdk_bdev * prev )

Get the next registered block device.

Parameters

prev	The current block device.

Returns: The next registered block device.

◆ spdk_bdev_next_leaf()

struct spdk_bdev * spdk_bdev_next_leaf ( struct spdk_bdev * prev )

Get the next block device without virtual block devices on top.

This function only traverses over block devices which have no virtual block devices on top of them, then get the next one.

Parameters

prev	The current block device.

Returns: The next block device without virtual block devices on top.

◆ spdk_bdev_open_async()

int spdk_bdev_open_async	(	const char *	bdev_name,
		bool	write,
		spdk_bdev_event_cb_t	event_cb,
		void *	event_ctx,
		struct spdk_bdev_open_async_opts *	opts,
		spdk_bdev_open_async_cb_t	open_cb,
		void *	open_cb_arg )

Open a block device for I/O operations asynchronously with options.

Parameters

bdev_name	Block device name to open.
write	true is read/write access requested, false if read-only
event_cb	Notification callback to be called when the bdev triggers asynchronous event such as bdev removal. This will always be called on the same thread that spdk_bdev_open_async() was called on. In case of removal event the descriptor will have to be manually closed to make the bdev unregister proceed.
event_ctx	param for event_cb.
opts	Options for asynchronous block device open. If NULL, default values are used.
open_cb	Open callback.
open_cb_arg	Parameter for open_cb.

Returns: 0 if operation started successfully, suitable errno value otherwise

◆ spdk_bdev_open_ext()

int spdk_bdev_open_ext	(	const char *	bdev_name,
		bool	write,
		spdk_bdev_event_cb_t	event_cb,
		void *	event_ctx,
		struct spdk_bdev_desc **	desc )

Open a block device for I/O operations.

Parameters

bdev_name	Block device name to open.
write	true is read/write access requested, false if read-only
event_cb	notification callback to be called when the bdev triggers asynchronous event such as bdev removal. This will always be called on the same thread that spdk_bdev_open_ext() was called on. In case of removal event the descriptor will have to be manually closed to make the bdev unregister proceed.
event_ctx	param for event_cb.
desc	output parameter for the descriptor when operation is successful

Returns: 0 if operation is successful, suitable errno value otherwise

◆ spdk_bdev_queue_io_wait()

int spdk_bdev_queue_io_wait	(	struct spdk_bdev *	bdev,
		struct spdk_io_channel *	ch,
		struct spdk_bdev_io_wait_entry *	entry )

Add an entry into the calling thread's queue to be notified when an spdk_bdev_io becomes available.

When one of the bdev I/O Submit Functions returns -ENOMEM, it means the spdk_bdev_io buffer pool has no available buffers. This function may be called to register a callback to be notified when a buffer becomes available on the calling thread.

The callback function will always be called on the same thread as this function was called.

This function must only be called immediately after one of the bdev I/O Submit Functions returns -ENOMEM.

Parameters

bdev	Block device. The block device that the caller will submit an I/O to when the callback is invoked. Must match the bdev member in the entry parameter.
ch	I/O channel. Obtained by calling spdk_bdev_get_io_channel().
entry	Data structure allocated by the caller specifying the callback function and argument.

Returns: 0 on success. -EINVAL if bdev parameter does not match bdev member in entry -EINVAL if an spdk_bdev_io structure was available on this thread.

◆ spdk_bdev_set_qd_sampling_period()

void spdk_bdev_set_qd_sampling_period	(	struct spdk_bdev *	bdev,
		uint64_t	period )

Enable or disable queue depth sampling for this bdev.

Enables queue depth sampling when period is greater than 0. Disables it when the period is equal to zero. The resulting queue depth is stored in the spdk_bdev object as measured_queue_depth.

Parameters

bdev	Block device on which to enable queue depth tracking.
period	The period at which to poll this bdev's queue depth. If this is set to zero, polling will be disabled.

◆ spdk_bdev_set_qos_rate_limits()

void spdk_bdev_set_qos_rate_limits	(	struct spdk_bdev *	bdev,
		uint64_t *	limits,
		void()(void cb_arg, int status)	cb_fn,
		void *	cb_arg )

Set the quality of service rate limits on a bdev.

Parameters

bdev	Block device.
limits	Pointer to the QoS rate limits array which holding the limits.
cb_fn	Callback function to be called when the QoS limit has been updated.
cb_arg	Argument to pass to cb_fn.

The limits are ordered based on the spdk_bdev_qos_rate_limit_type enum.

◆ spdk_bdev_set_timeout()

int spdk_bdev_set_timeout	(	struct spdk_bdev_desc *	desc,
		uint64_t	timeout_in_sec,
		spdk_bdev_io_timeout_cb	cb_fn,
		void *	cb_arg )

Set a time limit for the timeout IO of the bdev and timeout callback.

We can use this function to enable/disable the timeout handler. If the timeout_in_sec > 0 then it means to enable the timeout IO handling or change the time limit. If the timeout_in_sec == 0 it means to disable the timeout IO handling. If you want to enable or change the timeout IO handle you need to specify the spdk_bdev_io_timeout_cb it means the upper user determines what to do if you meet the timeout IO, for example, you can reset the device or abort the IO. Note: This function must run in the desc's thread.

Parameters

desc	Block device descriptor.
timeout_in_sec	Timeout value
cb_fn	Bdev IO timeout callback
cb_arg	Callback argument

Returns: 0 on success, negated errno on failure.

◆ spdk_bdev_subsystem_config_json()

void spdk_bdev_subsystem_config_json ( struct spdk_json_write_ctx * w )

Get the full configuration options for the registered block device modules and created bdevs.

Parameters

w	pointer to a JSON write context where the configuration will be written.

◆ spdk_bdev_wait_for_examine()

int spdk_bdev_wait_for_examine	(	spdk_bdev_wait_for_examine_cb	cb_fn,
		void *	cb_arg )

Report when all bdevs finished the examine process.

The registered cb_fn will be called just once. This function needs to be called again to receive further reports on examine process.

Parameters

cb_fn	Callback function.
cb_arg	Callback argument.

Returns: 0 if function was registered, suitable errno value otherwise

◆ spdk_bdev_zcopy_end()

int spdk_bdev_zcopy_end	(	struct spdk_bdev_io *	bdev_io,
		bool	commit,
		spdk_bdev_io_completion_cb	cb,
		void *	cb_arg )

Submit a request to release a data buffer representing a range of blocks.

Parameters

bdev_io	I/O request returned in the completion callback of spdk_bdev_zcopy_start().
commit	Whether to commit the data in the buffers to the blocks before releasing. The data does not need to be committed if it was not modified.
cb	Called when the request is complete.
cb_arg	Argument passed to cb.

Returns: 0 on success. On success, the callback will always be called (even if the request ultimately failed). Return negated errno on failure, in which case the callback will not be called.

◆ spdk_bdev_zcopy_start()

int spdk_bdev_zcopy_start	(	struct spdk_bdev_desc *	desc,
		struct spdk_io_channel *	ch,
		struct iovec *	iov,
		int	iovcnt,
		uint64_t	offset_blocks,
		uint64_t	num_blocks,
		bool	populate,
		spdk_bdev_io_completion_cb	cb,
		void *	cb_arg )

Submit a request to acquire a data buffer that represents the given range of blocks.

The data buffer is placed in the spdk_bdev_io structure and can be obtained by calling spdk_bdev_io_get_iovec().

Parameters

desc	Block device descriptor
ch	I/O channel. Obtained by calling spdk_bdev_get_io_channel().
iov	A scatter gather list to be populated with the buffers
iovcnt	The maximum number of elements in iov.
offset_blocks	The offset, in blocks, from the start of the block device.
num_blocks	The number of blocks.
populate	Whether the data buffer should be populated with the data at the given blocks. Populating the data buffer can be skipped if the user writes new data to the entire buffer.
cb	Called when the request is complete.
cb_arg	Argument passed to cb.

Returns: 0 on success. On success, the callback will always be called (even if the request ultimately failed). Return negated errno on failure, in which case the callback will not be called.

◆ spdk_for_each_bdev()

int spdk_for_each_bdev	(	void *	ctx,
		spdk_for_each_bdev_fn	fn )

Call the provided callback function for every registered block device.

If fn returns negated errno, spdk_for_each_bdev() terminates iteration.

spdk_for_each_bdev() opens before and closes after executing the provided callback function for each bdev internally.

Parameters

ctx	Context passed to the callback function.
fn	Callback function for each block device.

Returns: 0 if operation is successful, or suitable errno value one of the callback returned otherwise.

◆ spdk_for_each_bdev_leaf()

int spdk_for_each_bdev_leaf	(	void *	ctx,
		spdk_for_each_bdev_fn	fn )

Call the provided callback function for every block device without virtual block devices on top.

spdk_for_each_bdev_leaf() opens before and closes after executing the provided callback function for each unclaimed bdev internally.

Parameters

ctx	Context passed to the callback function.
fn	Callback function for each block device without virtual block devices on top.

Returns: 0 if operation is successful, or suitable errno value one of the callback returned otherwise.

Data Structures

Macros

Typedefs

Enumerations

Functions

Detailed Description

Typedef Documentation

◆ spdk_bdev_event_cb_t

◆ spdk_bdev_fini_cb

◆ spdk_bdev_for_each_channel_done

◆ spdk_bdev_for_each_channel_msg

◆ spdk_bdev_init_cb

◆ spdk_bdev_io_completion_cb

◆ spdk_bdev_io_timeout_cb

◆ spdk_bdev_io_wait_cb

◆ spdk_bdev_open_async_cb_t

◆ spdk_bdev_remove_cb_t

◆ spdk_for_each_bdev_fn

Enumeration Type Documentation

◆ spdk_bdev_qos_rate_limit_type

Function Documentation

◆ spdk_bdev_channel_get_histogram()

◆ spdk_bdev_close()

◆ spdk_bdev_desc_get_bdev()

◆ spdk_bdev_dump_info_json()

◆ spdk_bdev_enable_histogram_opts_init()

◆ spdk_bdev_examine()

◆ spdk_bdev_finish()

◆ spdk_bdev_first()

◆ spdk_bdev_first_leaf()

◆ spdk_bdev_for_each_channel()

◆ spdk_bdev_for_each_channel_continue()

◆ spdk_bdev_free_io()

◆ spdk_bdev_get_acwu()

◆ spdk_bdev_get_block_size()

◆ spdk_bdev_get_buf_align()

◆ spdk_bdev_get_by_name()

◆ spdk_bdev_get_data_block_size()

◆ spdk_bdev_get_device_stat()

◆ spdk_bdev_get_dif_pi_format()

◆ spdk_bdev_get_dif_type()

◆ spdk_bdev_get_io_channel()

◆ spdk_bdev_get_io_stat()

◆ spdk_bdev_get_io_time()

◆ spdk_bdev_get_io_type()

◆ spdk_bdev_get_io_type_name()

◆ spdk_bdev_get_max_copy()

◆ spdk_bdev_get_md_size()

◆ spdk_bdev_get_media_events()

◆ spdk_bdev_get_memory_domains()

◆ spdk_bdev_get_module_ctx()

◆ spdk_bdev_get_module_name()

◆ spdk_bdev_get_name()

◆ spdk_bdev_get_num_blocks()

◆ spdk_bdev_get_numa_id()

◆ spdk_bdev_get_nvme_ctratt()

◆ spdk_bdev_get_optimal_io_boundary()

◆ spdk_bdev_get_opts()

◆ spdk_bdev_get_physical_block_size()

◆ spdk_bdev_get_product_name()

◆ spdk_bdev_get_qd()

◆ spdk_bdev_get_qd_sampling_period()

◆ spdk_bdev_get_qos_rate_limits()

◆ spdk_bdev_get_qos_rpc_type()

◆ spdk_bdev_get_uuid()

◆ spdk_bdev_get_weighted_io_time()

◆ spdk_bdev_get_write_unit_size()

◆ spdk_bdev_has_write_cache()

◆ spdk_bdev_histogram_enable()

◆ spdk_bdev_histogram_enable_ext()

◆ spdk_bdev_histogram_get()

◆ spdk_bdev_initialize()

◆ spdk_bdev_io_get_aio_status()

◆ spdk_bdev_io_get_cb_arg()

◆ spdk_bdev_io_get_iovec()

◆ spdk_bdev_io_get_md_buf()

◆ spdk_bdev_io_get_nvme_fused_status()

◆ spdk_bdev_io_get_nvme_status()

◆ spdk_bdev_io_get_scsi_status()

◆ spdk_bdev_io_get_seek_offset()