numam-spdk/include/spdk/bdev.h
Jim Harris be9a3b9f69 bdev: pass descriptors for I/O operations
This enables checking permissions - for example,
spdk_bdev_write will fail if the descriptor was not
created with write permissions.

Signed-off-by: Jim Harris <james.r.harris@intel.com>
Change-Id: I68b65a560f471f2e0f71a7f42cfa6689b911110f

Reviewed-on: https://review.gerrithub.io/369493
Tested-by: SPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
Reviewed-by: Daniel Verkamp <daniel.verkamp@intel.com>
2017-07-14 13:31:30 -04:00

502 lines
18 KiB
C

/*-
* BSD LICENSE
*
* Copyright (C) 2008-2012 Daisuke Aoyama <aoyama@peach.ne.jp>.
* Copyright (c) Intel Corporation.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* * Neither the name of Intel Corporation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/** \file
* Block device abstraction layer
*/
#ifndef SPDK_BDEV_H_
#define SPDK_BDEV_H_
#include "spdk/stdinc.h"
#include "spdk/scsi_spec.h"
#include "spdk/nvme_spec.h"
#define SPDK_BDEV_SMALL_BUF_MAX_SIZE 8192
#define SPDK_BDEV_LARGE_BUF_MAX_SIZE (64 * 1024)
typedef void (*spdk_bdev_remove_cb_t)(void *remove_ctx);
/**
* Block device I/O
*
* This is an I/O that is passed to an spdk_bdev.
*/
struct spdk_bdev_io;
struct spdk_bdev_fn_table;
struct spdk_io_channel;
struct spdk_json_write_ctx;
/** bdev status */
enum spdk_bdev_status {
SPDK_BDEV_STATUS_INVALID,
SPDK_BDEV_STATUS_READY,
SPDK_BDEV_STATUS_REMOVING,
};
/**
* \brief SPDK block device.
*
* This is a virtual representation of a block device that is exported by the backend.
*/
struct spdk_bdev;
/**
* \brief Handle to an opened SPDK block device.
*/
struct spdk_bdev_desc;
/** bdev I/O type */
enum spdk_bdev_io_type {
SPDK_BDEV_IO_TYPE_READ = 1,
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,
};
/**
* Block device completion callback
*
* \param bdev_io Block device I/O that has completed.
* \param 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().
* \param cb_arg Callback argument specified when bdev_io was submitted.
*/
typedef void (*spdk_bdev_io_completion_cb)(struct spdk_bdev_io *bdev_io,
bool success,
void *cb_arg);
struct spdk_bdev_io_stat {
uint64_t bytes_read;
uint64_t num_read_ops;
uint64_t bytes_written;
uint64_t num_write_ops;
};
struct spdk_bdev_poller;
typedef void (*spdk_bdev_init_cb)(void *cb_arg, int rc);
typedef void (*spdk_bdev_poller_fn)(void *arg);
typedef void (*spdk_bdev_poller_start_cb)(struct spdk_bdev_poller **ppoller,
spdk_bdev_poller_fn fn,
void *arg,
uint32_t lcore,
uint64_t period_microseconds);
typedef void (*spdk_bdev_poller_stop_cb)(struct spdk_bdev_poller **ppoller);
void spdk_bdev_initialize(spdk_bdev_init_cb cb_fn, void *cb_arg,
spdk_bdev_poller_start_cb start_poller_fn,
spdk_bdev_poller_stop_cb stop_poller_fn);
int spdk_bdev_finish(void);
void spdk_bdev_config_text(FILE *fp);
struct spdk_bdev *spdk_bdev_get_by_name(const char *bdev_name);
/**
* These two functions iterate the full list of bdevs, including bdevs
* that have virtual bdevs on top of them.
*/
struct spdk_bdev *spdk_bdev_first(void);
struct spdk_bdev *spdk_bdev_next(struct spdk_bdev *prev);
/**
* These two functions only iterate over bdevs which have no virtual
* bdevs on top of them.
*/
struct spdk_bdev *spdk_bdev_first_leaf(void);
struct spdk_bdev *spdk_bdev_next_leaf(struct spdk_bdev *prev);
/**
* Open a block device for I/O operations.
*
* \param bdev Block device to open.
* \param write true is read/write access requested, false if read-only
* \param remove_cb callback function for hot remove the device.
* \param remove_ctx param for hot removal callback function.
* \param desc output parameter for the descriptor when operation is successful
* \return 0 if operation is successful, suitable errno value otherwise
*/
int spdk_bdev_open(struct spdk_bdev *bdev, bool write, spdk_bdev_remove_cb_t remove_cb,
void *remove_ctx, struct spdk_bdev_desc **desc);
/**
* Close a previously opened block device.
*
* \param desc Block device descriptor to close.
*/
void spdk_bdev_close(struct spdk_bdev_desc *desc);
/**
* Get the bdev associated with a bdev descriptor.
*
* \param desc Open block device desciptor
* \return bdev associated with the descriptor
*/
struct spdk_bdev *spdk_bdev_desc_get_bdev(struct spdk_bdev_desc *desc);
bool spdk_bdev_io_type_supported(struct spdk_bdev *bdev, enum spdk_bdev_io_type io_type);
int spdk_bdev_dump_config_json(struct spdk_bdev *bdev, struct spdk_json_write_ctx *w);
/**
* Get block device name.
*
* \param bdev Block device to query.
* \return Name of bdev as a null-terminated string.
*/
const char *spdk_bdev_get_name(const struct spdk_bdev *bdev);
/**
* Get block device product name.
*
* \param bdev Block device to query.
* \return Product name of bdev as a null-terminated string.
*/
const char *spdk_bdev_get_product_name(const struct spdk_bdev *bdev);
/**
* Get block device logical block size.
*
* \param bdev Block device to query.
* \return Size of logical block for this bdev in bytes.
*/
uint32_t spdk_bdev_get_block_size(const struct spdk_bdev *bdev);
/**
* Get size of block device in logical blocks.
*
* \param bdev Block device to query.
* \return Size of bdev in logical blocks.
*
* Logical blocks are numbered from 0 to spdk_bdev_get_num_blocks(bdev) - 1, inclusive.
*/
uint64_t spdk_bdev_get_num_blocks(const struct spdk_bdev *bdev);
/**
* Get maximum number of descriptors per unmap request.
*
* \param bdev Block device to query.
* \return Maximum number of unmap descriptors per request.
*/
uint32_t spdk_bdev_get_max_unmap_descriptors(const struct spdk_bdev *bdev);
/**
* Get minimum I/O buffer address alignment for a bdev.
*
* \param bdev Block device to query.
* \return Required alignment of I/O buffers in bytes.
*/
size_t spdk_bdev_get_buf_align(const struct spdk_bdev *bdev);
/**
* Query whether block device has an enabled write cache.
*
* \param bdev Block device to query.
* \return 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.
*/
bool spdk_bdev_has_write_cache(const struct spdk_bdev *bdev);
/**
* 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.
*
* \param desc Block device descriptor
*
* \return A handle to the I/O channel or NULL on failure.
*/
struct spdk_io_channel *spdk_bdev_get_io_channel(struct spdk_bdev_desc *desc);
/**
* Submit a read request to the bdev on the given channel.
*
* \param bdev Block device
* \param ch I/O channel. Obtained by calling spdk_bdev_get_io_channel().
* \param buf Data buffer to read into.
* \param offset The offset, in bytes, from the start of the block device.
* \param nbytes The number of bytes to read.
* \param cb Called when the request is complete.
* \param cb_arg Argument passed to cb.
*
* \return 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.
*/
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. This differs from
* spdk_bdev_read by allowing the data buffer to be described in a scatter
* gather list. Some physical devices place memory alignment requirements on
* data and may not be able to directly transfer into the buffers provided. In
* this case, the request may fail.
*
* \param bdev Block device
* \param ch I/O channel. Obtained by calling spdk_bdev_get_io_channel().
* \param iov A scatter gather list of buffers to be read into.
* \param iovcnt The number of elements in iov.
* \param offset The offset, in bytes, from the start of the block device.
* \param nbytes The number of bytes to read.
* \param cb Called when the request is complete.
* \param cb_arg Argument passed to cb.
*
* \return 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.
*/
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 write request to the bdev on the given channel.
*
* \param bdev Block device
* \param ch I/O channel. Obtained by calling spdk_bdev_get_io_channel().
* \param buf Data buffer to written from.
* \param offset The offset, in bytes, from the start of the block device.
* \param nbytes The number of bytes to write. buf must be greater than or equal to this size.
* \param cb Called when the request is complete.
* \param cb_arg Argument passed to cb.
*
* \return 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.
*/
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. This differs from
* spdk_bdev_write by allowing the data buffer to be described in a scatter
* gather list. Some physical devices place memory alignment requirements on
* data and may not be able to directly transfer out of the buffers provided. In
* this case, the request may fail.
*
* \param bdev Block device
* \param ch I/O channel. Obtained by calling spdk_bdev_get_io_channel().
* \param iov A scatter gather list of buffers to be written from.
* \param iovcnt The number of elements in iov.
* \param offset The offset, in bytes, from the start of the block device.
* \param nbytes The number of bytes to read. buf must be greater than or equal to this size.
* \param cb Called when the request is complete.
* \param cb_arg Argument passed to cb.
*
* \return 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.
*/
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 an unmap request to the block device. Unmap is sometimes also called trim or
* deallocate. This notifies the device that the data in the blocks described is no
* longer valid. Reading blocks that have been unmapped results in indeterminate data.
*
* \param bdev Block device
* \param ch I/O channel. Obtained by calling spdk_bdev_get_io_channel().
* \param unmap_d An array of unmap descriptors.
* \param bdesc_count The number of elements in unmap_d.
* \param cb Called when the request is complete.
* \param cb_arg Argument passed to cb.
*
* \return 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.
*/
int spdk_bdev_unmap(struct spdk_bdev_desc *desc, struct spdk_io_channel *ch,
struct spdk_scsi_unmap_bdesc *unmap_d,
uint16_t bdesc_count,
spdk_bdev_io_completion_cb cb, void *cb_arg);
/**
* Submit a flush request to the bdev on the given channel. For devices with volatile
* caches, data is not guaranteed to be persistent until the completion of a flush
* request. Call spdk_bdev_has_write_cache() to check if the bdev has a volatile cache.
*
* \param bdev Block device
* \param ch I/O channel. Obtained by calling spdk_bdev_get_io_channel().
* \param offset The offset, in bytes, from the start of the block device.
* \param length The number of bytes.
* \param cb Called when the request is complete.
* \param cb_arg Argument passed to cb.
*
* \return 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.
*/
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 reset request to the bdev on the given channel.
*
* \param bdev Block device
* \param ch I/O channel. Obtained by calling spdk_bdev_get_io_channel().
* \param cb Called when the request is complete.
* \param cb_arg Argument passed to cb.
*
* \return 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.
*/
int spdk_bdev_reset(struct spdk_bdev_desc *desc, struct spdk_io_channel *ch,
spdk_bdev_io_completion_cb cb, void *cb_arg);
/**
* Submit an NVMe Admin command to the bdev. This passes directly through
* the block layer to the device. Support for NVMe passthru is optional,
* indicated by calling spdk_bdev_io_type_supported().
*
* The SGL/PRP will be automated generated based on the given buffer,
* so that portion of the command may be left empty.
*
* \param bdev Block device
* \param ch I/O channel. Obtained by calling spdk_bdev_get_io_channel().
* \param cmd The raw NVMe command. Must be an admin command.
* \param buf Data buffer to written from.
* \param nbytes The number of bytes to transfer. buf must be greater than or equal to this size.
* \param cb Called when the request is complete.
* \param cb_arg Argument passed to cb.
*
* \return 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.
*/
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 I/O command to the bdev. This passes directly through
* the block layer to the device. Support for NVMe passthru is optional,
* indicated by calling spdk_bdev_io_type_supported().
*
* The SGL/PRP will be automated generated based on the given buffer,
* so that portion of the command may be left empty. Also, the namespace
* id (nsid) will be populated automatically.
*
* \param bdev Block device
* \param ch I/O channel. Obtained by calling spdk_bdev_get_io_channel().
* \param cmd The raw NVMe command. Must be in the NVM command set.
* \param buf Data buffer to written from.
* \param nbytes The number of bytes to transfer. buf must be greater than or equal to this size.
* \param cb Called when the request is complete.
* \param cb_arg Argument passed to cb.
*
* \return 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.
*/
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);
/**
* Free an I/O request. This should be called after the callback for the I/O has
* been called and notifies the bdev layer that memory may now be released.
*
* \param bdev_io I/O request
*
* \return -1 on failure, 0 on success.
*/
int spdk_bdev_free_io(struct spdk_bdev_io *bdev_io);
/**
* Return I/O statistics for this channel. After returning stats, zero out
* the current state of the statistics.
*
* \param bdev Block device
* \param ch I/O channel. Obtained by calling spdk_bdev_get_io_channel().
* \param stat The per-channel statistics.
*
*/
void spdk_bdev_get_io_stat(struct spdk_bdev *bdev, struct spdk_io_channel *ch,
struct spdk_bdev_io_stat *stat);
/**
* Get the status of bdev_io as an NVMe status code.
*
* \param bdev_io I/O to get the status from.
* \param sct Status Code Type return value, as defined by the NVMe specification.
* \param sc Status Code return value, as defined by the NVMe specification.
*/
void spdk_bdev_io_get_nvme_status(const struct spdk_bdev_io *bdev_io, int *sct, int *sc);
/**
* Get the status of bdev_io as a SCSI status code.
*
* \param bdev_io I/O to get the status from.
* \param sc SCSI Status Code.
* \param sk SCSI Sense Key.
* \param asc SCSI Additional Sense Code.
* \param ascq SCSI Additional Sense Code Qualifier.
*/
void spdk_bdev_io_get_scsi_status(const struct spdk_bdev_io *bdev_io,
int *sc, int *sk, int *asc, int *ascq);
/**
* Get the iovec describing the data buffer of a bdev_io.
*
* \param bdev_io I/O to describe with iovec.
* \param iovp Pointer to be filled with iovec.
* \param iovcntp Pointer to be filled with number of iovec entries.
*/
void spdk_bdev_io_get_iovec(struct spdk_bdev_io *bdev_io, struct iovec **iovp, int *iovcntp);
#endif /* SPDK_BDEV_H_ */