ceph/src/spdk/include/spdk/nbd.h

   1 /*-
   2  *   BSD LICENSE
   3  *
   4  *   Copyright (c) Intel Corporation.
   5  *   All rights reserved.
   6  *
   7  *   Redistribution and use in source and binary forms, with or without
   8  *   modification, are permitted provided that the following conditions
   9  *   are met:
  10  *
  11  *     * Redistributions of source code must retain the above copyright
  12  *       notice, this list of conditions and the following disclaimer.
  13  *     * Redistributions in binary form must reproduce the above copyright
  14  *       notice, this list of conditions and the following disclaimer in
  15  *       the documentation and/or other materials provided with the
  16  *       distribution.
  17  *     * Neither the name of Intel Corporation nor the names of its
  18  *       contributors may be used to endorse or promote products derived
  19  *       from this software without specific prior written permission.
  20  *
  21  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  24  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  25  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  26  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  27  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  28  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  29  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  30  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  32  */
  33
  34 /** \file
  35  * Network block device layer
  36  */
  37
  38 #ifndef SPDK_NBD_H_
  39 #define SPDK_NBD_H_
  40
  41 #ifdef __cplusplus
  42 extern "C" {
  43 #endif
  44
  45 struct spdk_bdev;
  46 struct spdk_nbd_disk;
  47 struct spdk_json_write_ctx;
  48
  49 /**
  50  * Initialize the network block device layer.
  51  *
  52  * \return 0 on success.
  53  */
  54 int spdk_nbd_init(void);
  55
  56 /**
  57  * Stop and close all the running network block devices.
  58  */
  59 void spdk_nbd_fini(void);
  60
  61 /**
  62  * Called when an NBD device has been started.
  63  * On success, rc is assigned 0; On failure, rc is assigned negated errno.
  64  */
  65 typedef void (*spdk_nbd_start_cb)(void *cb_arg, struct spdk_nbd_disk *nbd,
  66                                   int rc);
  67
  68 /**
  69  * Start a network block device backed by the bdev.
  70  *
  71  * \param bdev_name Name of bdev exposed as a network block device.
  72  * \param nbd_path Path to the registered network block device.
  73  * \param cb_fn Callback to be always called.
  74  * \param cb_arg Passed to cb_fn.
  75  */
  76 void spdk_nbd_start(const char *bdev_name, const char *nbd_path,
  77                     spdk_nbd_start_cb cb_fn, void *cb_arg);
  78
  79 /**
  80  * Stop the running network block device safely.
  81  *
  82  * \param nbd A pointer to the network block device to stop.
  83  */
  84 void spdk_nbd_stop(struct spdk_nbd_disk *nbd);
  85
  86 /**
  87  * Get the local filesystem path used for the network block device.
  88  */
  89 const char *spdk_nbd_get_path(struct spdk_nbd_disk *nbd);
  90
  91 /**
  92  * Write NBD subsystem configuration into provided JSON context.
  93  *
  94  * \param w JSON write context
  95  */
  96 void spdk_nbd_write_config_json(struct spdk_json_write_ctx *w);
  97
  98 #ifdef __cplusplus
  99 }
 100 #endif
 101
 102 #endif