include/linux/sunrpc/svc_rdma.h

   1 /* SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause */
   2 /*
   3  * Copyright (c) 2005-2006 Network Appliance, Inc. All rights reserved.
   4  *
   5  * This software is available to you under a choice of one of two
   6  * licenses.  You may choose to be licensed under the terms of the GNU
   7  * General Public License (GPL) Version 2, available from the file
   8  * COPYING in the main directory of this source tree, or the BSD-type
   9  * license below:
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  *
  15  *      Redistributions of source code must retain the above copyright
  16  *      notice, this list of conditions and the following disclaimer.
  17  *
  18  *      Redistributions in binary form must reproduce the above
  19  *      copyright notice, this list of conditions and the following
  20  *      disclaimer in the documentation and/or other materials provided
  21  *      with the distribution.
  22  *
  23  *      Neither the name of the Network Appliance, Inc. nor the names of
  24  *      its contributors may be used to endorse or promote products
  25  *      derived from this software without specific prior written
  26  *      permission.
  27  *
  28  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  29  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  30  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  31  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  32  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  33  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  34  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  35  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  36  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  37  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  38  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  39  *
  40  * Author: Tom Tucker <tom@opengridcomputing.com>
  41  */
  42
  43 #ifndef SVC_RDMA_H
  44 #define SVC_RDMA_H
  45 #include <linux/llist.h>
  46 #include <linux/sunrpc/xdr.h>
  47 #include <linux/sunrpc/svcsock.h>
  48 #include <linux/sunrpc/rpc_rdma.h>
  49 #include <linux/sunrpc/rpc_rdma_cid.h>
  50 #include <linux/sunrpc/svc_rdma_pcl.h>
  51 #include <linux/sunrpc/rdma_rn.h>
  52
  53 #include <linux/percpu_counter.h>
  54 #include <rdma/ib_verbs.h>
  55 #include <rdma/rdma_cm.h>
  56
  57 /* Default and maximum inline threshold sizes */
  58 enum {
  59         RPCRDMA_PULLUP_THRESH = RPCRDMA_V1_DEF_INLINE_SIZE >> 1,
  60         RPCRDMA_DEF_INLINE_THRESH = 4096,
  61         RPCRDMA_MAX_INLINE_THRESH = 65536
  62 };
  63
  64 /* RPC/RDMA parameters and stats */
  65 extern unsigned int svcrdma_ord;
  66 extern unsigned int svcrdma_max_requests;
  67 extern unsigned int svcrdma_max_bc_requests;
  68 extern unsigned int svcrdma_max_req_size;
  69 extern struct workqueue_struct *svcrdma_wq;
  70
  71 extern struct percpu_counter svcrdma_stat_read;
  72 extern struct percpu_counter svcrdma_stat_recv;
  73 extern struct percpu_counter svcrdma_stat_sq_starve;
  74 extern struct percpu_counter svcrdma_stat_write;
  75
  76 struct svcxprt_rdma {
  77         struct svc_xprt      sc_xprt;           /* SVC transport structure */
  78         struct rdma_cm_id    *sc_cm_id;         /* RDMA connection id */
  79         struct list_head     sc_accept_q;       /* Conn. waiting accept */
  80         struct rpcrdma_notification sc_rn;      /* removal notification */
  81         int                  sc_ord;            /* RDMA read limit */
  82         int                  sc_max_send_sges;
  83         bool                 sc_snd_w_inv;      /* OK to use Send With Invalidate */
  84
  85         atomic_t             sc_sq_avail;       /* SQEs ready to be consumed */
  86         unsigned int         sc_sq_depth;       /* Depth of SQ */
  87         __be32               sc_fc_credits;     /* Forward credits */
  88         u32                  sc_max_requests;   /* Max requests */
  89         u32                  sc_max_bc_requests;/* Backward credits */
  90         int                  sc_max_req_size;   /* Size of each RQ WR buf */
  91         u8                   sc_port_num;
  92
  93         struct ib_pd         *sc_pd;
  94
  95         spinlock_t           sc_send_lock;
  96         struct llist_head    sc_send_ctxts;
  97         spinlock_t           sc_rw_ctxt_lock;
  98         struct llist_head    sc_rw_ctxts;
  99
 100         u32                  sc_pending_recvs;
 101         u32                  sc_recv_batch;
 102         struct list_head     sc_rq_dto_q;
 103         struct list_head     sc_read_complete_q;
 104         spinlock_t           sc_rq_dto_lock;
 105         struct ib_qp         *sc_qp;
 106         struct ib_cq         *sc_rq_cq;
 107         struct ib_cq         *sc_sq_cq;
 108
 109         spinlock_t           sc_lock;           /* transport lock */
 110
 111         wait_queue_head_t    sc_send_wait;      /* SQ exhaustion waitlist */
 112         unsigned long        sc_flags;
 113         struct work_struct   sc_work;
 114
 115         struct llist_head    sc_recv_ctxts;
 116
 117         atomic_t             sc_completion_ids;
 118 };
 119 /* sc_flags */
 120 #define RDMAXPRT_CONN_PENDING   3
 121
 122 static inline struct svcxprt_rdma *svc_rdma_rqst_rdma(struct svc_rqst *rqstp)
 123 {
 124         struct svc_xprt *xprt = rqstp->rq_xprt;
 125
 126         return container_of(xprt, struct svcxprt_rdma, sc_xprt);
 127 }
 128
 129 /*
 130  * Default connection parameters
 131  */
 132 enum {
 133         RPCRDMA_LISTEN_BACKLOG  = 10,
 134         RPCRDMA_MAX_REQUESTS    = 64,
 135         RPCRDMA_MAX_BC_REQUESTS = 2,
 136 };
 137
 138 #define RPCSVC_MAXPAYLOAD_RDMA  RPCSVC_MAXPAYLOAD
 139
 140 /**
 141  * svc_rdma_send_cid_init - Initialize a Receive Queue completion ID
 142  * @rdma: controlling transport
 143  * @cid: completion ID to initialize
 144  */
 145 static inline void svc_rdma_recv_cid_init(struct svcxprt_rdma *rdma,
 146                                           struct rpc_rdma_cid *cid)
 147 {
 148         cid->ci_queue_id = rdma->sc_rq_cq->res.id;
 149         cid->ci_completion_id = atomic_inc_return(&rdma->sc_completion_ids);
 150 }
 151
 152 /**
 153  * svc_rdma_send_cid_init - Initialize a Send Queue completion ID
 154  * @rdma: controlling transport
 155  * @cid: completion ID to initialize
 156  */
 157 static inline void svc_rdma_send_cid_init(struct svcxprt_rdma *rdma,
 158                                           struct rpc_rdma_cid *cid)
 159 {
 160         cid->ci_queue_id = rdma->sc_sq_cq->res.id;
 161         cid->ci_completion_id = atomic_inc_return(&rdma->sc_completion_ids);
 162 }
 163
 164 /*
 165  * A chunk context tracks all I/O for moving one Read or Write
 166  * chunk. This is a set of rdma_rw's that handle data movement
 167  * for all segments of one chunk.
 168  */
 169 struct svc_rdma_chunk_ctxt {
 170         struct rpc_rdma_cid     cc_cid;
 171         struct ib_cqe           cc_cqe;
 172         struct list_head        cc_rwctxts;
 173         ktime_t                 cc_posttime;
 174         int                     cc_sqecount;
 175 };
 176
 177 struct svc_rdma_recv_ctxt {
 178         struct llist_node       rc_node;
 179         struct list_head        rc_list;
 180         struct ib_recv_wr       rc_recv_wr;
 181         struct ib_cqe           rc_cqe;
 182         struct rpc_rdma_cid     rc_cid;
 183         struct ib_sge           rc_recv_sge;
 184         void                    *rc_recv_buf;
 185         struct xdr_stream       rc_stream;
 186         u32                     rc_byte_len;
 187         u32                     rc_inv_rkey;
 188         __be32                  rc_msgtype;
 189
 190         /* State for pulling a Read chunk */
 191         unsigned int            rc_pageoff;
 192         unsigned int            rc_curpage;
 193         unsigned int            rc_readbytes;
 194         struct xdr_buf          rc_saved_arg;
 195         struct svc_rdma_chunk_ctxt      rc_cc;
 196
 197         struct svc_rdma_pcl     rc_call_pcl;
 198
 199         struct svc_rdma_pcl     rc_read_pcl;
 200         struct svc_rdma_chunk   *rc_cur_result_payload;
 201         struct svc_rdma_pcl     rc_write_pcl;
 202         struct svc_rdma_pcl     rc_reply_pcl;
 203
 204         unsigned int            rc_page_count;
 205         struct page             *rc_pages[RPCSVC_MAXPAGES];
 206 };
 207
 208 /*
 209  * State for sending a Write chunk.
 210  *  - Tracks progress of writing one chunk over all its segments
 211  *  - Stores arguments for the SGL constructor functions
 212  */
 213 struct svc_rdma_write_info {
 214         struct svcxprt_rdma     *wi_rdma;
 215
 216         const struct svc_rdma_chunk     *wi_chunk;
 217
 218         /* write state of this chunk */
 219         unsigned int            wi_seg_off;
 220         unsigned int            wi_seg_no;
 221
 222         /* SGL constructor arguments */
 223         const struct xdr_buf    *wi_xdr;
 224         unsigned char           *wi_base;
 225         unsigned int            wi_next_off;
 226
 227         struct svc_rdma_chunk_ctxt      wi_cc;
 228         struct work_struct      wi_work;
 229 };
 230
 231 struct svc_rdma_send_ctxt {
 232         struct llist_node       sc_node;
 233         struct rpc_rdma_cid     sc_cid;
 234         struct work_struct      sc_work;
 235
 236         struct svcxprt_rdma     *sc_rdma;
 237         struct ib_send_wr       sc_send_wr;
 238         struct ib_send_wr       *sc_wr_chain;
 239         int                     sc_sqecount;
 240         struct ib_cqe           sc_cqe;
 241         struct xdr_buf          sc_hdrbuf;
 242         struct xdr_stream       sc_stream;
 243         struct svc_rdma_write_info sc_reply_info;
 244         void                    *sc_xprt_buf;
 245         int                     sc_page_count;
 246         int                     sc_cur_sge_no;
 247         struct page             *sc_pages[RPCSVC_MAXPAGES];
 248         struct ib_sge           sc_sges[];
 249 };
 250
 251 /* svc_rdma_backchannel.c */
 252 extern void svc_rdma_handle_bc_reply(struct svc_rqst *rqstp,
 253                                      struct svc_rdma_recv_ctxt *rctxt);
 254
 255 /* svc_rdma_recvfrom.c */
 256 extern void svc_rdma_recv_ctxts_destroy(struct svcxprt_rdma *rdma);
 257 extern bool svc_rdma_post_recvs(struct svcxprt_rdma *rdma);
 258 extern struct svc_rdma_recv_ctxt *
 259                 svc_rdma_recv_ctxt_get(struct svcxprt_rdma *rdma);
 260 extern void svc_rdma_recv_ctxt_put(struct svcxprt_rdma *rdma,
 261                                    struct svc_rdma_recv_ctxt *ctxt);
 262 extern void svc_rdma_flush_recv_queues(struct svcxprt_rdma *rdma);
 263 extern void svc_rdma_release_ctxt(struct svc_xprt *xprt, void *ctxt);
 264 extern int svc_rdma_recvfrom(struct svc_rqst *);
 265
 266 /* svc_rdma_rw.c */
 267 extern void svc_rdma_cc_init(struct svcxprt_rdma *rdma,
 268                              struct svc_rdma_chunk_ctxt *cc);
 269 extern void svc_rdma_destroy_rw_ctxts(struct svcxprt_rdma *rdma);
 270 extern void svc_rdma_cc_init(struct svcxprt_rdma *rdma,
 271                              struct svc_rdma_chunk_ctxt *cc);
 272 extern void svc_rdma_cc_release(struct svcxprt_rdma *rdma,
 273                                 struct svc_rdma_chunk_ctxt *cc,
 274                                 enum dma_data_direction dir);
 275 extern void svc_rdma_reply_chunk_release(struct svcxprt_rdma *rdma,
 276                                          struct svc_rdma_send_ctxt *ctxt);
 277 extern int svc_rdma_send_write_list(struct svcxprt_rdma *rdma,
 278                                     const struct svc_rdma_recv_ctxt *rctxt,
 279                                     const struct xdr_buf *xdr);
 280 extern int svc_rdma_prepare_reply_chunk(struct svcxprt_rdma *rdma,
 281                                         const struct svc_rdma_pcl *write_pcl,
 282                                         const struct svc_rdma_pcl *reply_pcl,
 283                                         struct svc_rdma_send_ctxt *sctxt,
 284                                         const struct xdr_buf *xdr);
 285 extern int svc_rdma_process_read_list(struct svcxprt_rdma *rdma,
 286                                       struct svc_rqst *rqstp,
 287                                       struct svc_rdma_recv_ctxt *head);
 288
 289 /* svc_rdma_sendto.c */
 290 extern void svc_rdma_send_ctxts_destroy(struct svcxprt_rdma *rdma);
 291 extern struct svc_rdma_send_ctxt *
 292                 svc_rdma_send_ctxt_get(struct svcxprt_rdma *rdma);
 293 extern void svc_rdma_send_ctxt_put(struct svcxprt_rdma *rdma,
 294                                    struct svc_rdma_send_ctxt *ctxt);
 295 extern int svc_rdma_post_send(struct svcxprt_rdma *rdma,
 296                               struct svc_rdma_send_ctxt *ctxt);
 297 extern int svc_rdma_map_reply_msg(struct svcxprt_rdma *rdma,
 298                                   struct svc_rdma_send_ctxt *sctxt,
 299                                   const struct svc_rdma_pcl *write_pcl,
 300                                   const struct svc_rdma_pcl *reply_pcl,
 301                                   const struct xdr_buf *xdr);
 302 extern void svc_rdma_send_error_msg(struct svcxprt_rdma *rdma,
 303                                     struct svc_rdma_send_ctxt *sctxt,
 304                                     struct svc_rdma_recv_ctxt *rctxt,
 305                                     int status);
 306 extern void svc_rdma_wake_send_waiters(struct svcxprt_rdma *rdma, int avail);
 307 extern int svc_rdma_sendto(struct svc_rqst *);
 308 extern int svc_rdma_result_payload(struct svc_rqst *rqstp, unsigned int offset,
 309                                    unsigned int length);
 310
 311 /* svc_rdma_transport.c */
 312 extern struct svc_xprt_class svc_rdma_class;
 313 #ifdef CONFIG_SUNRPC_BACKCHANNEL
 314 extern struct svc_xprt_class svc_rdma_bc_class;
 315 #endif
 316
 317 /* svc_rdma.c */
 318 extern int svc_rdma_init(void);
 319 extern void svc_rdma_cleanup(void);
 320
 321 #endif