net/sunrpc/xprtrdma/xprt_rdma.h

   1 /*
   2  * Copyright (c) 2014-2017 Oracle.  All rights reserved.
   3  * Copyright (c) 2003-2007 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
  41 #ifndef _LINUX_SUNRPC_XPRT_RDMA_H
  42 #define _LINUX_SUNRPC_XPRT_RDMA_H
  43
  44 #include <linux/wait.h>                 /* wait_queue_head_t, etc */
  45 #include <linux/spinlock.h>             /* spinlock_t, etc */
  46 #include <linux/atomic.h>                       /* atomic_t, etc */
  47 #include <linux/workqueue.h>            /* struct work_struct */
  48
  49 #include <rdma/rdma_cm.h>               /* RDMA connection api */
  50 #include <rdma/ib_verbs.h>              /* RDMA verbs api */
  51
  52 #include <linux/sunrpc/clnt.h>          /* rpc_xprt */
  53 #include <linux/sunrpc/rpc_rdma.h>      /* RPC/RDMA protocol */
  54 #include <linux/sunrpc/xprtrdma.h>      /* xprt parameters */
  55
  56 #define RDMA_RESOLVE_TIMEOUT    (5000)  /* 5 seconds */
  57 #define RDMA_CONNECT_RETRY_MAX  (2)     /* retries if no listener backlog */
  58
  59 #define RPCRDMA_BIND_TO         (60U * HZ)
  60 #define RPCRDMA_INIT_REEST_TO   (5U * HZ)
  61 #define RPCRDMA_MAX_REEST_TO    (30U * HZ)
  62 #define RPCRDMA_IDLE_DISC_TO    (5U * 60 * HZ)
  63
  64 /*
  65  * Interface Adapter -- one per transport instance
  66  */
  67 struct rpcrdma_ia {
  68         const struct rpcrdma_memreg_ops *ri_ops;
  69         struct ib_device        *ri_device;
  70         struct rdma_cm_id       *ri_id;
  71         struct ib_pd            *ri_pd;
  72         struct completion       ri_done;
  73         struct completion       ri_remove_done;
  74         int                     ri_async_rc;
  75         unsigned int            ri_max_segs;
  76         unsigned int            ri_max_frmr_depth;
  77         unsigned int            ri_max_inline_write;
  78         unsigned int            ri_max_inline_read;
  79         unsigned int            ri_max_send_sges;
  80         bool                    ri_reminv_expected;
  81         bool                    ri_implicit_roundup;
  82         enum ib_mr_type         ri_mrtype;
  83         unsigned long           ri_flags;
  84         struct ib_qp_attr       ri_qp_attr;
  85         struct ib_qp_init_attr  ri_qp_init_attr;
  86 };
  87
  88 enum {
  89         RPCRDMA_IAF_REMOVING = 0,
  90 };
  91
  92 /*
  93  * RDMA Endpoint -- one per transport instance
  94  */
  95
  96 struct rpcrdma_ep {
  97         unsigned int            rep_send_count;
  98         unsigned int            rep_send_batch;
  99         int                     rep_connected;
 100         struct ib_qp_init_attr  rep_attr;
 101         wait_queue_head_t       rep_connect_wait;
 102         struct rpcrdma_connect_private  rep_cm_private;
 103         struct rdma_conn_param  rep_remote_cma;
 104         struct sockaddr_storage rep_remote_addr;
 105         struct delayed_work     rep_connect_worker;
 106 };
 107
 108 /* Pre-allocate extra Work Requests for handling backward receives
 109  * and sends. This is a fixed value because the Work Queues are
 110  * allocated when the forward channel is set up.
 111  */
 112 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
 113 #define RPCRDMA_BACKWARD_WRS            (8)
 114 #else
 115 #define RPCRDMA_BACKWARD_WRS            (0)
 116 #endif
 117
 118 /* Registered buffer -- registered kmalloc'd memory for RDMA SEND/RECV
 119  *
 120  * The below structure appears at the front of a large region of kmalloc'd
 121  * memory, which always starts on a good alignment boundary.
 122  */
 123
 124 struct rpcrdma_regbuf {
 125         struct ib_sge           rg_iov;
 126         struct ib_device        *rg_device;
 127         enum dma_data_direction rg_direction;
 128         __be32                  rg_base[0] __attribute__ ((aligned(256)));
 129 };
 130
 131 static inline u64
 132 rdmab_addr(struct rpcrdma_regbuf *rb)
 133 {
 134         return rb->rg_iov.addr;
 135 }
 136
 137 static inline u32
 138 rdmab_length(struct rpcrdma_regbuf *rb)
 139 {
 140         return rb->rg_iov.length;
 141 }
 142
 143 static inline u32
 144 rdmab_lkey(struct rpcrdma_regbuf *rb)
 145 {
 146         return rb->rg_iov.lkey;
 147 }
 148
 149 static inline struct ib_device *
 150 rdmab_device(struct rpcrdma_regbuf *rb)
 151 {
 152         return rb->rg_device;
 153 }
 154
 155 #define RPCRDMA_DEF_GFP         (GFP_NOIO | __GFP_NOWARN)
 156
 157 /* To ensure a transport can always make forward progress,
 158  * the number of RDMA segments allowed in header chunk lists
 159  * is capped at 8. This prevents less-capable devices and
 160  * memory registrations from overrunning the Send buffer
 161  * while building chunk lists.
 162  *
 163  * Elements of the Read list take up more room than the
 164  * Write list or Reply chunk. 8 read segments means the Read
 165  * list (or Write list or Reply chunk) cannot consume more
 166  * than
 167  *
 168  * ((8 + 2) * read segment size) + 1 XDR words, or 244 bytes.
 169  *
 170  * And the fixed part of the header is another 24 bytes.
 171  *
 172  * The smallest inline threshold is 1024 bytes, ensuring that
 173  * at least 750 bytes are available for RPC messages.
 174  */
 175 enum {
 176         RPCRDMA_MAX_HDR_SEGS = 8,
 177         RPCRDMA_HDRBUF_SIZE = 256,
 178 };
 179
 180 /*
 181  * struct rpcrdma_rep -- this structure encapsulates state required
 182  * to receive and complete an RPC Reply, asychronously. It needs
 183  * several pieces of state:
 184  *
 185  *   o receive buffer and ib_sge (donated to provider)
 186  *   o status of receive (success or not, length, inv rkey)
 187  *   o bookkeeping state to get run by reply handler (XDR stream)
 188  *
 189  * These structures are allocated during transport initialization.
 190  * N of these are associated with a transport instance, managed by
 191  * struct rpcrdma_buffer. N is the max number of outstanding RPCs.
 192  */
 193
 194 struct rpcrdma_rep {
 195         struct ib_cqe           rr_cqe;
 196         __be32                  rr_xid;
 197         __be32                  rr_vers;
 198         __be32                  rr_proc;
 199         int                     rr_wc_flags;
 200         u32                     rr_inv_rkey;
 201         struct rpcrdma_regbuf   *rr_rdmabuf;
 202         struct rpcrdma_xprt     *rr_rxprt;
 203         struct work_struct      rr_work;
 204         struct xdr_buf          rr_hdrbuf;
 205         struct xdr_stream       rr_stream;
 206         struct rpc_rqst         *rr_rqst;
 207         struct list_head        rr_list;
 208         struct ib_recv_wr       rr_recv_wr;
 209 };
 210
 211 /* struct rpcrdma_sendctx - DMA mapped SGEs to unmap after Send completes
 212  */
 213 struct rpcrdma_req;
 214 struct rpcrdma_xprt;
 215 struct rpcrdma_sendctx {
 216         struct ib_send_wr       sc_wr;
 217         struct ib_cqe           sc_cqe;
 218         struct rpcrdma_xprt     *sc_xprt;
 219         struct rpcrdma_req      *sc_req;
 220         unsigned int            sc_unmap_count;
 221         struct ib_sge           sc_sges[];
 222 };
 223
 224 /* Limit the number of SGEs that can be unmapped during one
 225  * Send completion. This caps the amount of work a single
 226  * completion can do before returning to the provider.
 227  *
 228  * Setting this to zero disables Send completion batching.
 229  */
 230 enum {
 231         RPCRDMA_MAX_SEND_BATCH = 7,
 232 };
 233
 234 /*
 235  * struct rpcrdma_mw - external memory region metadata
 236  *
 237  * An external memory region is any buffer or page that is registered
 238  * on the fly (ie, not pre-registered).
 239  *
 240  * Each rpcrdma_buffer has a list of free MWs anchored in rb_mws. During
 241  * call_allocate, rpcrdma_buffer_get() assigns one to each segment in
 242  * an rpcrdma_req. Then rpcrdma_register_external() grabs these to keep
 243  * track of registration metadata while each RPC is pending.
 244  * rpcrdma_deregister_external() uses this metadata to unmap and
 245  * release these resources when an RPC is complete.
 246  */
 247 enum rpcrdma_frmr_state {
 248         FRMR_IS_INVALID,        /* ready to be used */
 249         FRMR_IS_VALID,          /* in use */
 250         FRMR_FLUSHED_FR,        /* flushed FASTREG WR */
 251         FRMR_FLUSHED_LI,        /* flushed LOCALINV WR */
 252 };
 253
 254 struct rpcrdma_frmr {
 255         struct ib_mr                    *fr_mr;
 256         struct ib_cqe                   fr_cqe;
 257         enum rpcrdma_frmr_state         fr_state;
 258         struct completion               fr_linv_done;
 259         union {
 260                 struct ib_reg_wr        fr_regwr;
 261                 struct ib_send_wr       fr_invwr;
 262         };
 263 };
 264
 265 struct rpcrdma_fmr {
 266         struct ib_fmr           *fm_mr;
 267         u64                     *fm_physaddrs;
 268 };
 269
 270 struct rpcrdma_mw {
 271         struct list_head        mw_list;
 272         struct scatterlist      *mw_sg;
 273         int                     mw_nents;
 274         enum dma_data_direction mw_dir;
 275         unsigned long           mw_flags;
 276         union {
 277                 struct rpcrdma_fmr      fmr;
 278                 struct rpcrdma_frmr     frmr;
 279         };
 280         struct rpcrdma_xprt     *mw_xprt;
 281         u32                     mw_handle;
 282         u32                     mw_length;
 283         u64                     mw_offset;
 284         struct list_head        mw_all;
 285 };
 286
 287 /* mw_flags */
 288 enum {
 289         RPCRDMA_MW_F_RI         = 1,
 290 };
 291
 292 /*
 293  * struct rpcrdma_req -- structure central to the request/reply sequence.
 294  *
 295  * N of these are associated with a transport instance, and stored in
 296  * struct rpcrdma_buffer. N is the max number of outstanding requests.
 297  *
 298  * It includes pre-registered buffer memory for send AND recv.
 299  * The recv buffer, however, is not owned by this structure, and
 300  * is "donated" to the hardware when a recv is posted. When a
 301  * reply is handled, the recv buffer used is given back to the
 302  * struct rpcrdma_req associated with the request.
 303  *
 304  * In addition to the basic memory, this structure includes an array
 305  * of iovs for send operations. The reason is that the iovs passed to
 306  * ib_post_{send,recv} must not be modified until the work request
 307  * completes.
 308  */
 309
 310 /* Maximum number of page-sized "segments" per chunk list to be
 311  * registered or invalidated. Must handle a Reply chunk:
 312  */
 313 enum {
 314         RPCRDMA_MAX_IOV_SEGS    = 3,
 315         RPCRDMA_MAX_DATA_SEGS   = ((1 * 1024 * 1024) / PAGE_SIZE) + 1,
 316         RPCRDMA_MAX_SEGS        = RPCRDMA_MAX_DATA_SEGS +
 317                                   RPCRDMA_MAX_IOV_SEGS,
 318 };
 319
 320 struct rpcrdma_mr_seg {         /* chunk descriptors */
 321         u32             mr_len;         /* length of chunk or segment */
 322         struct page     *mr_page;       /* owning page, if any */
 323         char            *mr_offset;     /* kva if no page, else offset */
 324 };
 325
 326 /* The Send SGE array is provisioned to send a maximum size
 327  * inline request:
 328  * - RPC-over-RDMA header
 329  * - xdr_buf head iovec
 330  * - RPCRDMA_MAX_INLINE bytes, in pages
 331  * - xdr_buf tail iovec
 332  *
 333  * The actual number of array elements consumed by each RPC
 334  * depends on the device's max_sge limit.
 335  */
 336 enum {
 337         RPCRDMA_MIN_SEND_SGES = 3,
 338         RPCRDMA_MAX_PAGE_SGES = RPCRDMA_MAX_INLINE >> PAGE_SHIFT,
 339         RPCRDMA_MAX_SEND_SGES = 1 + 1 + RPCRDMA_MAX_PAGE_SGES + 1,
 340 };
 341
 342 struct rpcrdma_buffer;
 343 struct rpcrdma_req {
 344         struct list_head        rl_list;
 345         unsigned int            rl_connect_cookie;
 346         struct rpcrdma_buffer   *rl_buffer;
 347         struct rpcrdma_rep      *rl_reply;
 348         struct xdr_stream       rl_stream;
 349         struct xdr_buf          rl_hdrbuf;
 350         struct rpcrdma_sendctx  *rl_sendctx;
 351         struct rpcrdma_regbuf   *rl_rdmabuf;    /* xprt header */
 352         struct rpcrdma_regbuf   *rl_sendbuf;    /* rq_snd_buf */
 353         struct rpcrdma_regbuf   *rl_recvbuf;    /* rq_rcv_buf */
 354
 355         struct list_head        rl_all;
 356         unsigned long           rl_flags;
 357
 358         struct list_head        rl_registered;  /* registered segments */
 359         struct rpcrdma_mr_seg   rl_segments[RPCRDMA_MAX_SEGS];
 360 };
 361
 362 /* rl_flags */
 363 enum {
 364         RPCRDMA_REQ_F_BACKCHANNEL = 0,
 365         RPCRDMA_REQ_F_PENDING,
 366         RPCRDMA_REQ_F_TX_RESOURCES,
 367 };
 368
 369 static inline void
 370 rpcrdma_set_xprtdata(struct rpc_rqst *rqst, struct rpcrdma_req *req)
 371 {
 372         rqst->rq_xprtdata = req;
 373 }
 374
 375 static inline struct rpcrdma_req *
 376 rpcr_to_rdmar(struct rpc_rqst *rqst)
 377 {
 378         return rqst->rq_xprtdata;
 379 }
 380
 381 static inline void
 382 rpcrdma_push_mw(struct rpcrdma_mw *mw, struct list_head *list)
 383 {
 384         list_add_tail(&mw->mw_list, list);
 385 }
 386
 387 static inline struct rpcrdma_mw *
 388 rpcrdma_pop_mw(struct list_head *list)
 389 {
 390         struct rpcrdma_mw *mw;
 391
 392         mw = list_first_entry(list, struct rpcrdma_mw, mw_list);
 393         list_del(&mw->mw_list);
 394         return mw;
 395 }
 396
 397 /*
 398  * struct rpcrdma_buffer -- holds list/queue of pre-registered memory for
 399  * inline requests/replies, and client/server credits.
 400  *
 401  * One of these is associated with a transport instance
 402  */
 403 struct rpcrdma_buffer {
 404         spinlock_t              rb_mwlock;      /* protect rb_mws list */
 405         struct list_head        rb_mws;
 406         struct list_head        rb_all;
 407
 408         unsigned long           rb_sc_head;
 409         unsigned long           rb_sc_tail;
 410         unsigned long           rb_sc_last;
 411         struct rpcrdma_sendctx  **rb_sc_ctxs;
 412
 413         spinlock_t              rb_lock;        /* protect buf lists */
 414         int                     rb_send_count, rb_recv_count;
 415         struct list_head        rb_send_bufs;
 416         struct list_head        rb_recv_bufs;
 417         u32                     rb_max_requests;
 418         u32                     rb_credits;     /* most recent credit grant */
 419
 420         u32                     rb_bc_srv_max_requests;
 421         spinlock_t              rb_reqslock;    /* protect rb_allreqs */
 422         struct list_head        rb_allreqs;
 423
 424         u32                     rb_bc_max_requests;
 425
 426         spinlock_t              rb_recovery_lock; /* protect rb_stale_mrs */
 427         struct list_head        rb_stale_mrs;
 428         struct delayed_work     rb_recovery_worker;
 429         struct delayed_work     rb_refresh_worker;
 430 };
 431 #define rdmab_to_ia(b) (&container_of((b), struct rpcrdma_xprt, rx_buf)->rx_ia)
 432
 433 /*
 434  * Internal structure for transport instance creation. This
 435  * exists primarily for modularity.
 436  *
 437  * This data should be set with mount options
 438  */
 439 struct rpcrdma_create_data_internal {
 440         struct sockaddr_storage addr;   /* RDMA server address */
 441         unsigned int    max_requests;   /* max requests (slots) in flight */
 442         unsigned int    rsize;          /* mount rsize - max read hdr+data */
 443         unsigned int    wsize;          /* mount wsize - max write hdr+data */
 444         unsigned int    inline_rsize;   /* max non-rdma read data payload */
 445         unsigned int    inline_wsize;   /* max non-rdma write data payload */
 446         unsigned int    padding;        /* non-rdma write header padding */
 447 };
 448
 449 /*
 450  * Statistics for RPCRDMA
 451  */
 452 struct rpcrdma_stats {
 453         /* accessed when sending a call */
 454         unsigned long           read_chunk_count;
 455         unsigned long           write_chunk_count;
 456         unsigned long           reply_chunk_count;
 457         unsigned long long      total_rdma_request;
 458
 459         /* rarely accessed error counters */
 460         unsigned long long      pullup_copy_count;
 461         unsigned long           hardway_register_count;
 462         unsigned long           failed_marshal_count;
 463         unsigned long           bad_reply_count;
 464         unsigned long           mrs_recovered;
 465         unsigned long           mrs_orphaned;
 466         unsigned long           mrs_allocated;
 467         unsigned long           empty_sendctx_q;
 468
 469         /* accessed when receiving a reply */
 470         unsigned long long      total_rdma_reply;
 471         unsigned long long      fixup_copy_count;
 472         unsigned long           reply_waits_for_send;
 473         unsigned long           local_inv_needed;
 474         unsigned long           nomsg_call_count;
 475         unsigned long           bcall_count;
 476 };
 477
 478 /*
 479  * Per-registration mode operations
 480  */
 481 struct rpcrdma_xprt;
 482 struct rpcrdma_memreg_ops {
 483         struct rpcrdma_mr_seg *
 484                         (*ro_map)(struct rpcrdma_xprt *,
 485                                   struct rpcrdma_mr_seg *, int, bool,
 486                                   struct rpcrdma_mw **);
 487         void            (*ro_unmap_sync)(struct rpcrdma_xprt *,
 488                                          struct list_head *);
 489         void            (*ro_recover_mr)(struct rpcrdma_mw *);
 490         int             (*ro_open)(struct rpcrdma_ia *,
 491                                    struct rpcrdma_ep *,
 492                                    struct rpcrdma_create_data_internal *);
 493         size_t          (*ro_maxpages)(struct rpcrdma_xprt *);
 494         int             (*ro_init_mr)(struct rpcrdma_ia *,
 495                                       struct rpcrdma_mw *);
 496         void            (*ro_release_mr)(struct rpcrdma_mw *);
 497         const char      *ro_displayname;
 498         const int       ro_send_w_inv_ok;
 499 };
 500
 501 extern const struct rpcrdma_memreg_ops rpcrdma_fmr_memreg_ops;
 502 extern const struct rpcrdma_memreg_ops rpcrdma_frwr_memreg_ops;
 503
 504 /*
 505  * RPCRDMA transport -- encapsulates the structures above for
 506  * integration with RPC.
 507  *
 508  * The contained structures are embedded, not pointers,
 509  * for convenience. This structure need not be visible externally.
 510  *
 511  * It is allocated and initialized during mount, and released
 512  * during unmount.
 513  */
 514 struct rpcrdma_xprt {
 515         struct rpc_xprt         rx_xprt;
 516         struct rpcrdma_ia       rx_ia;
 517         struct rpcrdma_ep       rx_ep;
 518         struct rpcrdma_buffer   rx_buf;
 519         struct rpcrdma_create_data_internal rx_data;
 520         struct delayed_work     rx_connect_worker;
 521         struct rpcrdma_stats    rx_stats;
 522 };
 523
 524 #define rpcx_to_rdmax(x) container_of(x, struct rpcrdma_xprt, rx_xprt)
 525 #define rpcx_to_rdmad(x) (rpcx_to_rdmax(x)->rx_data)
 526
 527 /* Setting this to 0 ensures interoperability with early servers.
 528  * Setting this to 1 enhances certain unaligned read/write performance.
 529  * Default is 0, see sysctl entry and rpc_rdma.c rpcrdma_convert_iovs() */
 530 extern int xprt_rdma_pad_optimize;
 531
 532 /* This setting controls the hunt for a supported memory
 533  * registration strategy.
 534  */
 535 extern unsigned int xprt_rdma_memreg_strategy;
 536
 537 /*
 538  * Interface Adapter calls - xprtrdma/verbs.c
 539  */
 540 int rpcrdma_ia_open(struct rpcrdma_xprt *xprt, struct sockaddr *addr);
 541 void rpcrdma_ia_remove(struct rpcrdma_ia *ia);
 542 void rpcrdma_ia_close(struct rpcrdma_ia *);
 543 bool frwr_is_supported(struct rpcrdma_ia *);
 544 bool fmr_is_supported(struct rpcrdma_ia *);
 545
 546 extern struct workqueue_struct *rpcrdma_receive_wq;
 547
 548 /*
 549  * Endpoint calls - xprtrdma/verbs.c
 550  */
 551 int rpcrdma_ep_create(struct rpcrdma_ep *, struct rpcrdma_ia *,
 552                                 struct rpcrdma_create_data_internal *);
 553 void rpcrdma_ep_destroy(struct rpcrdma_ep *, struct rpcrdma_ia *);
 554 int rpcrdma_ep_connect(struct rpcrdma_ep *, struct rpcrdma_ia *);
 555 void rpcrdma_conn_func(struct rpcrdma_ep *ep);
 556 void rpcrdma_ep_disconnect(struct rpcrdma_ep *, struct rpcrdma_ia *);
 557
 558 int rpcrdma_ep_post(struct rpcrdma_ia *, struct rpcrdma_ep *,
 559                                 struct rpcrdma_req *);
 560 int rpcrdma_ep_post_recv(struct rpcrdma_ia *, struct rpcrdma_rep *);
 561
 562 /*
 563  * Buffer calls - xprtrdma/verbs.c
 564  */
 565 struct rpcrdma_req *rpcrdma_create_req(struct rpcrdma_xprt *);
 566 struct rpcrdma_rep *rpcrdma_create_rep(struct rpcrdma_xprt *);
 567 void rpcrdma_destroy_req(struct rpcrdma_req *);
 568 int rpcrdma_buffer_create(struct rpcrdma_xprt *);
 569 void rpcrdma_buffer_destroy(struct rpcrdma_buffer *);
 570 struct rpcrdma_sendctx *rpcrdma_sendctx_get_locked(struct rpcrdma_buffer *buf);
 571 void rpcrdma_sendctx_put_locked(struct rpcrdma_sendctx *sc);
 572
 573 struct rpcrdma_mw *rpcrdma_get_mw(struct rpcrdma_xprt *);
 574 void rpcrdma_put_mw(struct rpcrdma_xprt *, struct rpcrdma_mw *);
 575 struct rpcrdma_req *rpcrdma_buffer_get(struct rpcrdma_buffer *);
 576 void rpcrdma_buffer_put(struct rpcrdma_req *);
 577 void rpcrdma_recv_buffer_get(struct rpcrdma_req *);
 578 void rpcrdma_recv_buffer_put(struct rpcrdma_rep *);
 579
 580 void rpcrdma_defer_mr_recovery(struct rpcrdma_mw *);
 581
 582 struct rpcrdma_regbuf *rpcrdma_alloc_regbuf(size_t, enum dma_data_direction,
 583                                             gfp_t);
 584 bool __rpcrdma_dma_map_regbuf(struct rpcrdma_ia *, struct rpcrdma_regbuf *);
 585 void rpcrdma_free_regbuf(struct rpcrdma_regbuf *);
 586
 587 static inline bool
 588 rpcrdma_regbuf_is_mapped(struct rpcrdma_regbuf *rb)
 589 {
 590         return rb->rg_device != NULL;
 591 }
 592
 593 static inline bool
 594 rpcrdma_dma_map_regbuf(struct rpcrdma_ia *ia, struct rpcrdma_regbuf *rb)
 595 {
 596         if (likely(rpcrdma_regbuf_is_mapped(rb)))
 597                 return true;
 598         return __rpcrdma_dma_map_regbuf(ia, rb);
 599 }
 600
 601 int rpcrdma_ep_post_extra_recv(struct rpcrdma_xprt *, unsigned int);
 602
 603 int rpcrdma_alloc_wq(void);
 604 void rpcrdma_destroy_wq(void);
 605
 606 /*
 607  * Wrappers for chunk registration, shared by read/write chunk code.
 608  */
 609
 610 static inline enum dma_data_direction
 611 rpcrdma_data_dir(bool writing)
 612 {
 613         return writing ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
 614 }
 615
 616 /*
 617  * RPC/RDMA protocol calls - xprtrdma/rpc_rdma.c
 618  */
 619
 620 enum rpcrdma_chunktype {
 621         rpcrdma_noch = 0,
 622         rpcrdma_readch,
 623         rpcrdma_areadch,
 624         rpcrdma_writech,
 625         rpcrdma_replych
 626 };
 627
 628 int rpcrdma_prepare_send_sges(struct rpcrdma_xprt *r_xprt,
 629                               struct rpcrdma_req *req, u32 hdrlen,
 630                               struct xdr_buf *xdr,
 631                               enum rpcrdma_chunktype rtype);
 632 void rpcrdma_unmap_sendctx(struct rpcrdma_sendctx *sc);
 633 int rpcrdma_marshal_req(struct rpcrdma_xprt *r_xprt, struct rpc_rqst *rqst);
 634 void rpcrdma_set_max_header_sizes(struct rpcrdma_xprt *);
 635 void rpcrdma_complete_rqst(struct rpcrdma_rep *rep);
 636 void rpcrdma_reply_handler(struct rpcrdma_rep *rep);
 637 void rpcrdma_release_rqst(struct rpcrdma_xprt *r_xprt,
 638                           struct rpcrdma_req *req);
 639 void rpcrdma_deferred_completion(struct work_struct *work);
 640
 641 static inline void rpcrdma_set_xdrlen(struct xdr_buf *xdr, size_t len)
 642 {
 643         xdr->head[0].iov_len = len;
 644         xdr->len = len;
 645 }
 646
 647 /* RPC/RDMA module init - xprtrdma/transport.c
 648  */
 649 extern unsigned int xprt_rdma_max_inline_read;
 650 void xprt_rdma_format_addresses(struct rpc_xprt *xprt, struct sockaddr *sap);
 651 void xprt_rdma_free_addresses(struct rpc_xprt *xprt);
 652 void rpcrdma_connect_worker(struct work_struct *work);
 653 void xprt_rdma_print_stats(struct rpc_xprt *xprt, struct seq_file *seq);
 654 int xprt_rdma_init(void);
 655 void xprt_rdma_cleanup(void);
 656
 657 /* Backchannel calls - xprtrdma/backchannel.c
 658  */
 659 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
 660 int xprt_rdma_bc_setup(struct rpc_xprt *, unsigned int);
 661 int xprt_rdma_bc_up(struct svc_serv *, struct net *);
 662 size_t xprt_rdma_bc_maxpayload(struct rpc_xprt *);
 663 int rpcrdma_bc_post_recv(struct rpcrdma_xprt *, unsigned int);
 664 void rpcrdma_bc_receive_call(struct rpcrdma_xprt *, struct rpcrdma_rep *);
 665 int rpcrdma_bc_marshal_reply(struct rpc_rqst *);
 666 void xprt_rdma_bc_free_rqst(struct rpc_rqst *);
 667 void xprt_rdma_bc_destroy(struct rpc_xprt *, unsigned int);
 668 #endif  /* CONFIG_SUNRPC_BACKCHANNEL */
 669
 670 extern struct xprt_class xprt_rdma_bc;
 671
 672 #endif                          /* _LINUX_SUNRPC_XPRT_RDMA_H */