numam-spdk/lib/bdev/virtio/bdev_virtio.h
Dariusz Stojaczyk 1ce0368f99 bdev/virtio: cleanup public API
Cleaned up and expanded documentation
of virtio bdev module.

Change-Id: I4b989ed8b4d5e0bc66c0f0706e61219daf4e2869
Signed-off-by: Dariusz Stojaczyk <dariuszx.stojaczyk@intel.com>
Reviewed-on: https://review.gerrithub.io/390107
Tested-by: SPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: Daniel Verkamp <daniel.verkamp@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
2017-12-05 23:06:38 -05:00

77 lines
3.5 KiB
C

/*-
* BSD LICENSE
*
* 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
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* * Redistributions in binary form must reproduce the above copyright
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* 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
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* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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*/
#ifndef SPDK_BDEV_VIRTIO_H
#define SPDK_BDEV_VIRTIO_H
#include "spdk/bdev.h"
/**
* Callback for creating virtio bdevs.
*
* \param ctx opaque context set by the user
* \param errnum error code. 0 on success, negative errno on error.
* \param bdevs contiguous array of created bdevs
* \param bdev_cnt number of bdevs in the `bdevs` array
*/
typedef void (*bdev_virtio_create_cb)(void *ctx, int errnum,
struct spdk_bdev **bdevs, size_t bdev_cnt);
/**
* Connect to a vhost-user Unix domain socket and create a Virtio SCSI device.
* If the connection is successful, the device will be automatically scanned.
* The scan consists of probing the targets on the device and will result in
* creating possibly multiple Virtio SCSI bdevs - one for each target. Currently
* only one LUN per target is detected - LUN0. Note that the bdev creation is
* run asynchronously in the background. After it's finished, the `cb_fn`
* callback is called.
*
* \param name name for the virtio device. It will be inherited by all created
* bdevs, which are named in the following format: <name>t<target_id>
* \param path path to the socket
* \param num_queues max number of request virtqueues (I/O queues) to use.
* If given value exceeds a hard limit of the physical (host) device, this
* function will return with error.
* \param queue_size depth of each queue
* \param cb_fn function to be called after scanning all targets on the virtio
* device. It's optional, can be NULL. See \c bdev_virtio_create_cb.
* \param cb_arg argument for the `cb_fn`
* \return zero on success (device scan is started) or negative error code.
* In case of error the \c cb_fn is not called.
*/
int bdev_virtio_scsi_dev_create(const char *name, const char *path,
unsigned num_queues, unsigned queue_size,
bdev_virtio_create_cb cb_fn, void *cb_arg);
#endif /* SPDK_BDEV_VIRTIO_H */