LXR linux/include/linux/sunrpc/svc

   1/*
   2 * Copyright (c) 2005-2006 Network Appliance, Inc. All rights reserved.
   3 *
   4 * This software is available to you under a choice of one of two
   5 * licenses.  You may choose to be licensed under the terms of the GNU
   6 * General Public License (GPL) Version 2, available from the file
   7 * COPYING in the main directory of this source tree, or the BSD-type
   8 * license below:
   9 *
  10 * Redistribution and use in source and binary forms, with or without
  11 * modification, are permitted provided that the following conditions
  12 * are met:
  13 *
  14 *      Redistributions of source code must retain the above copyright
  15 *      notice, this list of conditions and the following disclaimer.
  16 *
  17 *      Redistributions in binary form must reproduce the above
  18 *      copyright notice, this list of conditions and the following
  19 *      disclaimer in the documentation and/or other materials provided
  20 *      with the distribution.
  21 *
  22 *      Neither the name of the Network Appliance, Inc. nor the names of
  23 *      its contributors may be used to endorse or promote products
  24 *      derived from this software without specific prior written
  25 *      permission.
  26 *
  27 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  28 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  29 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  30 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  31 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  32 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  33 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  34 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  35 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  36 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  37 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  38 *
  39 * Author: Tom Tucker <tom@opengridcomputing.com>
  40 */
  41
  42#ifndef SVC_RDMA_H
  43#define SVC_RDMA_H
  44#include <linux/sunrpc/xdr.h>
  45#include <linux/sunrpc/svcsock.h>
  46#include <linux/sunrpc/rpc_rdma.h>
  47#include <rdma/ib_verbs.h>
  48#include <rdma/rdma_cm.h>
  49#define SVCRDMA_DEBUG
  50
  51/* Default and maximum inline threshold sizes */
  52enum {
  53        RPCRDMA_DEF_INLINE_THRESH = 4096,
  54        RPCRDMA_MAX_INLINE_THRESH = 65536
  55};
  56
  57/* RPC/RDMA parameters and stats */
  58extern unsigned int svcrdma_ord;
  59extern unsigned int svcrdma_max_requests;
  60extern unsigned int svcrdma_max_bc_requests;
  61extern unsigned int svcrdma_max_req_size;
  62
  63extern atomic_t rdma_stat_recv;
  64extern atomic_t rdma_stat_read;
  65extern atomic_t rdma_stat_write;
  66extern atomic_t rdma_stat_sq_starve;
  67extern atomic_t rdma_stat_rq_starve;
  68extern atomic_t rdma_stat_rq_poll;
  69extern atomic_t rdma_stat_rq_prod;
  70extern atomic_t rdma_stat_sq_poll;
  71extern atomic_t rdma_stat_sq_prod;
  72
  73/*
  74 * Contexts are built when an RDMA request is created and are a
  75 * record of the resources that can be recovered when the request
  76 * completes.
  77 */
  78struct svc_rdma_op_ctxt {
  79        struct list_head list;
  80        struct xdr_buf arg;
  81        struct ib_cqe cqe;
  82        u32 byte_len;
  83        struct svcxprt_rdma *xprt;
  84        enum dma_data_direction direction;
  85        int count;
  86        unsigned int mapped_sges;
  87        int hdr_count;
  88        struct ib_send_wr send_wr;
  89        struct ib_sge sge[1 + RPCRDMA_MAX_INLINE_THRESH / PAGE_SIZE];
  90        struct page *pages[RPCSVC_MAXPAGES];
  91};
  92
  93struct svcxprt_rdma {
  94        struct svc_xprt      sc_xprt;           /* SVC transport structure */
  95        struct rdma_cm_id    *sc_cm_id;         /* RDMA connection id */
  96        struct list_head     sc_accept_q;       /* Conn. waiting accept */
  97        int                  sc_ord;            /* RDMA read limit */
  98        int                  sc_max_sge;
  99        bool                 sc_snd_w_inv;      /* OK to use Send With Invalidate */
 100
 101        atomic_t             sc_sq_avail;       /* SQEs ready to be consumed */
 102        unsigned int         sc_sq_depth;       /* Depth of SQ */
 103        unsigned int         sc_rq_depth;       /* Depth of RQ */
 104        __be32               sc_fc_credits;     /* Forward credits */
 105        u32                  sc_max_requests;   /* Max requests */
 106        u32                  sc_max_bc_requests;/* Backward credits */
 107        int                  sc_max_req_size;   /* Size of each RQ WR buf */
 108        u8                   sc_port_num;
 109
 110        struct ib_pd         *sc_pd;
 111
 112        spinlock_t           sc_ctxt_lock;
 113        struct list_head     sc_ctxts;
 114        int                  sc_ctxt_used;
 115        spinlock_t           sc_rw_ctxt_lock;
 116        struct list_head     sc_rw_ctxts;
 117
 118        struct list_head     sc_rq_dto_q;
 119        spinlock_t           sc_rq_dto_lock;
 120        struct ib_qp         *sc_qp;
 121        struct ib_cq         *sc_rq_cq;
 122        struct ib_cq         *sc_sq_cq;
 123
 124        spinlock_t           sc_lock;           /* transport lock */
 125
 126        wait_queue_head_t    sc_send_wait;      /* SQ exhaustion waitlist */
 127        unsigned long        sc_flags;
 128        struct list_head     sc_read_complete_q;
 129        struct work_struct   sc_work;
 130};
 131/* sc_flags */
 132#define RDMAXPRT_CONN_PENDING   3
 133
 134#define RPCRDMA_LISTEN_BACKLOG  10
 135/* The default ORD value is based on two outstanding full-size writes with a
 136 * page size of 4k, or 32k * 2 ops / 4k = 16 outstanding RDMA_READ.  */
 137#define RPCRDMA_ORD             (64/4)
 138#define RPCRDMA_MAX_REQUESTS    32
 139
 140/* Typical ULP usage of BC requests is NFSv4.1 backchannel. Our
 141 * current NFSv4.1 implementation supports one backchannel slot.
 142 */
 143#define RPCRDMA_MAX_BC_REQUESTS 2
 144
 145#define RPCSVC_MAXPAYLOAD_RDMA  RPCSVC_MAXPAYLOAD
 146
 147/* Track DMA maps for this transport and context */
 148static inline void svc_rdma_count_mappings(struct svcxprt_rdma *rdma,
 149                                           struct svc_rdma_op_ctxt *ctxt)
 150{
 151        ctxt->mapped_sges++;
 152}
 153
 154/* svc_rdma_backchannel.c */
 155extern int svc_rdma_handle_bc_reply(struct rpc_xprt *xprt,
 156                                    __be32 *rdma_resp,
 157                                    struct xdr_buf *rcvbuf);
 158
 159/* svc_rdma_recvfrom.c */
 160extern int svc_rdma_recvfrom(struct svc_rqst *);
 161
 162/* svc_rdma_rw.c */
 163extern void svc_rdma_destroy_rw_ctxts(struct svcxprt_rdma *rdma);
 164extern int svc_rdma_recv_read_chunk(struct svcxprt_rdma *rdma,
 165                                    struct svc_rqst *rqstp,
 166                                    struct svc_rdma_op_ctxt *head, __be32 *p);
 167extern int svc_rdma_send_write_chunk(struct svcxprt_rdma *rdma,
 168                                     __be32 *wr_ch, struct xdr_buf *xdr);
 169extern int svc_rdma_send_reply_chunk(struct svcxprt_rdma *rdma,
 170                                     __be32 *rp_ch, bool writelist,
 171                                     struct xdr_buf *xdr);
 172
 173/* svc_rdma_sendto.c */
 174extern int svc_rdma_map_reply_hdr(struct svcxprt_rdma *rdma,
 175                                  struct svc_rdma_op_ctxt *ctxt,
 176                                  __be32 *rdma_resp, unsigned int len);
 177extern int svc_rdma_post_send_wr(struct svcxprt_rdma *rdma,
 178                                 struct svc_rdma_op_ctxt *ctxt,
 179                                 int num_sge, u32 inv_rkey);
 180extern int svc_rdma_sendto(struct svc_rqst *);
 181
 182/* svc_rdma_transport.c */
 183extern void svc_rdma_wc_send(struct ib_cq *, struct ib_wc *);
 184extern void svc_rdma_wc_reg(struct ib_cq *, struct ib_wc *);
 185extern void svc_rdma_wc_read(struct ib_cq *, struct ib_wc *);
 186extern void svc_rdma_wc_inv(struct ib_cq *, struct ib_wc *);
 187extern int svc_rdma_send(struct svcxprt_rdma *, struct ib_send_wr *);
 188extern int svc_rdma_create_listen(struct svc_serv *, int, struct sockaddr *);
 189extern struct svc_rdma_op_ctxt *svc_rdma_get_context(struct svcxprt_rdma *);
 190extern void svc_rdma_put_context(struct svc_rdma_op_ctxt *, int);
 191extern void svc_rdma_unmap_dma(struct svc_rdma_op_ctxt *ctxt);
 192extern void svc_sq_reap(struct svcxprt_rdma *);
 193extern void svc_rq_reap(struct svcxprt_rdma *);
 194extern void svc_rdma_prep_reply_hdr(struct svc_rqst *);
 195
 196extern struct svc_xprt_class svc_rdma_class;
 197#ifdef CONFIG_SUNRPC_BACKCHANNEL
 198extern struct svc_xprt_class svc_rdma_bc_class;
 199#endif
 200
 201/* svc_rdma.c */
 202extern struct workqueue_struct *svc_rdma_wq;
 203extern int svc_rdma_init(void);
 204extern void svc_rdma_cleanup(void);
 205
 206#endif
 207