drivers/infiniband/ulp/rtrs/rtrs.h

   1 /* SPDX-License-Identifier: GPL-2.0-or-later */
   2 /*
   3  * RDMA Transport Layer
   4  *
   5  * Copyright (c) 2014 - 2018 ProfitBricks GmbH. All rights reserved.
   6  * Copyright (c) 2018 - 2019 1&1 IONOS Cloud GmbH. All rights reserved.
   7  * Copyright (c) 2019 - 2020 1&1 IONOS SE. All rights reserved.
   8  */
   9 #ifndef RTRS_H
  10 #define RTRS_H
  11
  12 #include <linux/socket.h>
  13 #include <linux/scatterlist.h>
  14
  15 struct rtrs_permit;
  16 struct rtrs_clt;
  17 struct rtrs_srv_ctx;
  18 struct rtrs_srv;
  19 struct rtrs_srv_op;
  20
  21 /*
  22  * RDMA transport (RTRS) client API
  23  */
  24
  25 /**
  26  * enum rtrs_clt_link_ev - Events about connectivity state of a client
  27  * @RTRS_CLT_LINK_EV_RECONNECTED        Client was reconnected.
  28  * @RTRS_CLT_LINK_EV_DISCONNECTED       Client was disconnected.
  29  */
  30 enum rtrs_clt_link_ev {
  31         RTRS_CLT_LINK_EV_RECONNECTED,
  32         RTRS_CLT_LINK_EV_DISCONNECTED,
  33 };
  34
  35 /**
  36  * Source and destination address of a path to be established
  37  */
  38 struct rtrs_addr {
  39         struct sockaddr_storage *src;
  40         struct sockaddr_storage *dst;
  41 };
  42
  43 /**
  44  * rtrs_clt_ops - it holds the link event callback and private pointer.
  45  * @priv: User supplied private data.
  46  * @link_ev: Event notification callback function for connection state changes
  47  *      @priv: User supplied data that was passed to rtrs_clt_open()
  48  *      @ev: Occurred event
  49  */
  50 struct rtrs_clt_ops {
  51         void    *priv;
  52         void    (*link_ev)(void *priv, enum rtrs_clt_link_ev ev);
  53 };
  54
  55 struct rtrs_clt *rtrs_clt_open(struct rtrs_clt_ops *ops,
  56                                  const char *sessname,
  57                                  const struct rtrs_addr *paths,
  58                                  size_t path_cnt, u16 port,
  59                                  size_t pdu_sz, u8 reconnect_delay_sec,
  60                                  u16 max_segments,
  61                                  size_t max_segment_size,
  62                                  s16 max_reconnect_attempts);
  63
  64 void rtrs_clt_close(struct rtrs_clt *sess);
  65
  66 enum {
  67         RTRS_PERMIT_NOWAIT = 0,
  68         RTRS_PERMIT_WAIT   = 1,
  69 };
  70
  71 /**
  72  * enum rtrs_clt_con_type() type of ib connection to use with a given
  73  * rtrs_permit
  74  * @ADMIN_CON - use connection reserved for "service" messages
  75  * @IO_CON - use a connection reserved for IO
  76  */
  77 enum rtrs_clt_con_type {
  78         RTRS_ADMIN_CON,
  79         RTRS_IO_CON
  80 };
  81
  82 struct rtrs_permit *rtrs_clt_get_permit(struct rtrs_clt *sess,
  83                                     enum rtrs_clt_con_type con_type,
  84                                     int wait);
  85
  86 void rtrs_clt_put_permit(struct rtrs_clt *sess, struct rtrs_permit *permit);
  87
  88 /**
  89  * rtrs_clt_req_ops - it holds the request confirmation callback
  90  * and a private pointer.
  91  * @priv: User supplied private data.
  92  * @conf_fn:    callback function to be called as confirmation
  93  *      @priv:  User provided data, passed back with corresponding
  94  *              @(conf) confirmation.
  95  *      @errno: error number.
  96  */
  97 struct rtrs_clt_req_ops {
  98         void    *priv;
  99         void    (*conf_fn)(void *priv, int errno);
 100 };
 101
 102 int rtrs_clt_request(int dir, struct rtrs_clt_req_ops *ops,
 103                      struct rtrs_clt *sess, struct rtrs_permit *permit,
 104                      const struct kvec *vec, size_t nr, size_t len,
 105                      struct scatterlist *sg, unsigned int sg_cnt);
 106
 107 /**
 108  * rtrs_attrs - RTRS session attributes
 109  */
 110 struct rtrs_attrs {
 111         u32             queue_depth;
 112         u32             max_io_size;
 113         u8              sessname[NAME_MAX];
 114         struct kobject  *sess_kobj;
 115 };
 116
 117 int rtrs_clt_query(struct rtrs_clt *sess, struct rtrs_attrs *attr);
 118
 119 /*
 120  * Here goes RTRS server API
 121  */
 122
 123 /**
 124  * enum rtrs_srv_link_ev - Server link events
 125  * @RTRS_SRV_LINK_EV_CONNECTED: Connection from client established
 126  * @RTRS_SRV_LINK_EV_DISCONNECTED:      Connection was disconnected, all
 127  *                                      connection RTRS resources were freed.
 128  */
 129 enum rtrs_srv_link_ev {
 130         RTRS_SRV_LINK_EV_CONNECTED,
 131         RTRS_SRV_LINK_EV_DISCONNECTED,
 132 };
 133
 134 struct rtrs_srv_ops {
 135         /**
 136          * rdma_ev():           Event notification for RDMA operations
 137          *                      If the callback returns a value != 0, an error
 138          *                      message for the data transfer will be sent to
 139          *                      the client.
 140
 141          *      @sess:          Session
 142          *      @priv:          Private data set by rtrs_srv_set_sess_priv()
 143          *      @id:            internal RTRS operation id
 144          *      @dir:           READ/WRITE
 145          *      @data:          Pointer to (bidirectional) rdma memory area:
 146          *                      - in case of %RTRS_SRV_RDMA_EV_RECV contains
 147          *                      data sent by the client
 148          *                      - in case of %RTRS_SRV_RDMA_EV_WRITE_REQ points
 149          *                      to the memory area where the response is to be
 150          *                      written to
 151          *      @datalen:       Size of the memory area in @data
 152          *      @usr:           The extra user message sent by the client (%vec)
 153          *      @usrlen:        Size of the user message
 154          */
 155         int (*rdma_ev)(struct rtrs_srv *sess, void *priv,
 156                        struct rtrs_srv_op *id, int dir,
 157                        void *data, size_t datalen, const void *usr,
 158                        size_t usrlen);
 159         /**
 160          * link_ev():           Events about connectivity state changes
 161          *                      If the callback returns != 0 and the event
 162          *                      %RTRS_SRV_LINK_EV_CONNECTED the corresponding
 163          *                      session will be destroyed.
 164          *      @sess:          Session
 165          *      @ev:            event
 166          *      @priv:          Private data from user if previously set with
 167          *                      rtrs_srv_set_sess_priv()
 168          */
 169         int (*link_ev)(struct rtrs_srv *sess, enum rtrs_srv_link_ev ev,
 170                        void *priv);
 171 };
 172
 173 struct rtrs_srv_ctx *rtrs_srv_open(struct rtrs_srv_ops *ops, u16 port);
 174
 175 void rtrs_srv_close(struct rtrs_srv_ctx *ctx);
 176
 177 bool rtrs_srv_resp_rdma(struct rtrs_srv_op *id, int errno);
 178
 179 void rtrs_srv_set_sess_priv(struct rtrs_srv *sess, void *priv);
 180
 181 int rtrs_srv_get_sess_name(struct rtrs_srv *sess, char *sessname, size_t len);
 182
 183 int rtrs_srv_get_queue_depth(struct rtrs_srv *sess);
 184
 185 int rtrs_addr_to_sockaddr(const char *str, size_t len, u16 port,
 186                           struct rtrs_addr *addr);
 187
 188 int sockaddr_to_str(const struct sockaddr *addr, char *buf, size_t len);
 189 #endif