include/rdma/rdmavt_qp.h

   1 #ifndef DEF_RDMAVT_INCQP_H
   2 #define DEF_RDMAVT_INCQP_H
   3
   4 /*
   5  * Copyright(c) 2016, 2017 Intel Corporation.
   6  *
   7  * This file is provided under a dual BSD/GPLv2 license.  When using or
   8  * redistributing this file, you may do so under either license.
   9  *
  10  * GPL LICENSE SUMMARY
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of version 2 of the GNU General Public License as
  14  * published by the Free Software Foundation.
  15  *
  16  * This program is distributed in the hope that it will be useful, but
  17  * WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  19  * General Public License for more details.
  20  *
  21  * BSD LICENSE
  22  *
  23  * Redistribution and use in source and binary forms, with or without
  24  * modification, are permitted provided that the following conditions
  25  * are met:
  26  *
  27  *  - Redistributions of source code must retain the above copyright
  28  *    notice, this list of conditions and the following disclaimer.
  29  *  - Redistributions in binary form must reproduce the above copyright
  30  *    notice, this list of conditions and the following disclaimer in
  31  *    the documentation and/or other materials provided with the
  32  *    distribution.
  33  *  - Neither the name of Intel Corporation nor the names of its
  34  *    contributors may be used to endorse or promote products derived
  35  *    from this software without specific prior written permission.
  36  *
  37  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  38  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  39  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  40  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  41  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  42  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  43  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  44  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  45  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  46  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  47  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  48  *
  49  */
  50
  51 #include <rdma/rdma_vt.h>
  52 #include <rdma/ib_pack.h>
  53 #include <rdma/ib_verbs.h>
  54 #include <rdma/rdmavt_cq.h>
  55 /*
  56  * Atomic bit definitions for r_aflags.
  57  */
  58 #define RVT_R_WRID_VALID        0
  59 #define RVT_R_REWIND_SGE        1
  60
  61 /*
  62  * Bit definitions for r_flags.
  63  */
  64 #define RVT_R_REUSE_SGE 0x01
  65 #define RVT_R_RDMAR_SEQ 0x02
  66 #define RVT_R_RSP_NAK   0x04
  67 #define RVT_R_RSP_SEND  0x08
  68 #define RVT_R_COMM_EST  0x10
  69
  70 /*
  71  * Bit definitions for s_flags.
  72  *
  73  * RVT_S_SIGNAL_REQ_WR - set if QP send WRs contain completion signaled
  74  * RVT_S_BUSY - send tasklet is processing the QP
  75  * RVT_S_TIMER - the RC retry timer is active
  76  * RVT_S_ACK_PENDING - an ACK is waiting to be sent after RDMA read/atomics
  77  * RVT_S_WAIT_FENCE - waiting for all prior RDMA read or atomic SWQEs
  78  *                         before processing the next SWQE
  79  * RVT_S_WAIT_RDMAR - waiting for a RDMA read or atomic SWQE to complete
  80  *                         before processing the next SWQE
  81  * RVT_S_WAIT_RNR - waiting for RNR timeout
  82  * RVT_S_WAIT_SSN_CREDIT - waiting for RC credits to process next SWQE
  83  * RVT_S_WAIT_DMA - waiting for send DMA queue to drain before generating
  84  *                  next send completion entry not via send DMA
  85  * RVT_S_WAIT_PIO - waiting for a send buffer to be available
  86  * RVT_S_WAIT_PIO_DRAIN - waiting for a qp to drain pio packets
  87  * RVT_S_WAIT_TX - waiting for a struct verbs_txreq to be available
  88  * RVT_S_WAIT_DMA_DESC - waiting for DMA descriptors to be available
  89  * RVT_S_WAIT_KMEM - waiting for kernel memory to be available
  90  * RVT_S_WAIT_PSN - waiting for a packet to exit the send DMA queue
  91  * RVT_S_WAIT_ACK - waiting for an ACK packet before sending more requests
  92  * RVT_S_SEND_ONE - send one packet, request ACK, then wait for ACK
  93  * RVT_S_ECN - a BECN was queued to the send engine
  94  */
  95 #define RVT_S_SIGNAL_REQ_WR     0x0001
  96 #define RVT_S_BUSY              0x0002
  97 #define RVT_S_TIMER             0x0004
  98 #define RVT_S_RESP_PENDING      0x0008
  99 #define RVT_S_ACK_PENDING       0x0010
 100 #define RVT_S_WAIT_FENCE        0x0020
 101 #define RVT_S_WAIT_RDMAR        0x0040
 102 #define RVT_S_WAIT_RNR          0x0080
 103 #define RVT_S_WAIT_SSN_CREDIT   0x0100
 104 #define RVT_S_WAIT_DMA          0x0200
 105 #define RVT_S_WAIT_PIO          0x0400
 106 #define RVT_S_WAIT_PIO_DRAIN    0x0800
 107 #define RVT_S_WAIT_TX           0x1000
 108 #define RVT_S_WAIT_DMA_DESC     0x2000
 109 #define RVT_S_WAIT_KMEM         0x4000
 110 #define RVT_S_WAIT_PSN          0x8000
 111 #define RVT_S_WAIT_ACK          0x10000
 112 #define RVT_S_SEND_ONE          0x20000
 113 #define RVT_S_UNLIMITED_CREDIT  0x40000
 114 #define RVT_S_AHG_VALID         0x80000
 115 #define RVT_S_AHG_CLEAR         0x100000
 116 #define RVT_S_ECN               0x200000
 117
 118 /*
 119  * Wait flags that would prevent any packet type from being sent.
 120  */
 121 #define RVT_S_ANY_WAIT_IO \
 122         (RVT_S_WAIT_PIO | RVT_S_WAIT_PIO_DRAIN | RVT_S_WAIT_TX | \
 123          RVT_S_WAIT_DMA_DESC | RVT_S_WAIT_KMEM)
 124
 125 /*
 126  * Wait flags that would prevent send work requests from making progress.
 127  */
 128 #define RVT_S_ANY_WAIT_SEND (RVT_S_WAIT_FENCE | RVT_S_WAIT_RDMAR | \
 129         RVT_S_WAIT_RNR | RVT_S_WAIT_SSN_CREDIT | RVT_S_WAIT_DMA | \
 130         RVT_S_WAIT_PSN | RVT_S_WAIT_ACK)
 131
 132 #define RVT_S_ANY_WAIT (RVT_S_ANY_WAIT_IO | RVT_S_ANY_WAIT_SEND)
 133
 134 /* Number of bits to pay attention to in the opcode for checking qp type */
 135 #define RVT_OPCODE_QP_MASK 0xE0
 136
 137 /* Flags for checking QP state (see ib_rvt_state_ops[]) */
 138 #define RVT_POST_SEND_OK                0x01
 139 #define RVT_POST_RECV_OK                0x02
 140 #define RVT_PROCESS_RECV_OK             0x04
 141 #define RVT_PROCESS_SEND_OK             0x08
 142 #define RVT_PROCESS_NEXT_SEND_OK        0x10
 143 #define RVT_FLUSH_SEND                  0x20
 144 #define RVT_FLUSH_RECV                  0x40
 145 #define RVT_PROCESS_OR_FLUSH_SEND \
 146         (RVT_PROCESS_SEND_OK | RVT_FLUSH_SEND)
 147 #define RVT_SEND_OR_FLUSH_OR_RECV_OK \
 148         (RVT_PROCESS_SEND_OK | RVT_FLUSH_SEND | RVT_PROCESS_RECV_OK)
 149
 150 /*
 151  * Internal send flags
 152  */
 153 #define RVT_SEND_RESERVE_USED           IB_SEND_RESERVED_START
 154 #define RVT_SEND_COMPLETION_ONLY        (IB_SEND_RESERVED_START << 1)
 155
 156 /*
 157  * Send work request queue entry.
 158  * The size of the sg_list is determined when the QP is created and stored
 159  * in qp->s_max_sge.
 160  */
 161 struct rvt_swqe {
 162         union {
 163                 struct ib_send_wr wr;   /* don't use wr.sg_list */
 164                 struct ib_ud_wr ud_wr;
 165                 struct ib_reg_wr reg_wr;
 166                 struct ib_rdma_wr rdma_wr;
 167                 struct ib_atomic_wr atomic_wr;
 168         };
 169         u32 psn;                /* first packet sequence number */
 170         u32 lpsn;               /* last packet sequence number */
 171         u32 ssn;                /* send sequence number */
 172         u32 length;             /* total length of data in sg_list */
 173         struct rvt_sge sg_list[0];
 174 };
 175
 176 /*
 177  * Receive work request queue entry.
 178  * The size of the sg_list is determined when the QP (or SRQ) is created
 179  * and stored in qp->r_rq.max_sge (or srq->rq.max_sge).
 180  */
 181 struct rvt_rwqe {
 182         u64 wr_id;
 183         u8 num_sge;
 184         struct ib_sge sg_list[0];
 185 };
 186
 187 /*
 188  * This structure is used to contain the head pointer, tail pointer,
 189  * and receive work queue entries as a single memory allocation so
 190  * it can be mmap'ed into user space.
 191  * Note that the wq array elements are variable size so you can't
 192  * just index into the array to get the N'th element;
 193  * use get_rwqe_ptr() instead.
 194  */
 195 struct rvt_rwq {
 196         u32 head;               /* new work requests posted to the head */
 197         u32 tail;               /* receives pull requests from here. */
 198         struct rvt_rwqe wq[0];
 199 };
 200
 201 struct rvt_rq {
 202         struct rvt_rwq *wq;
 203         u32 size;               /* size of RWQE array */
 204         u8 max_sge;
 205         /* protect changes in this struct */
 206         spinlock_t lock ____cacheline_aligned_in_smp;
 207 };
 208
 209 /*
 210  * This structure is used by rvt_mmap() to validate an offset
 211  * when an mmap() request is made.  The vm_area_struct then uses
 212  * this as its vm_private_data.
 213  */
 214 struct rvt_mmap_info {
 215         struct list_head pending_mmaps;
 216         struct ib_ucontext *context;
 217         void *obj;
 218         __u64 offset;
 219         struct kref ref;
 220         unsigned size;
 221 };
 222
 223 /*
 224  * This structure holds the information that the send tasklet needs
 225  * to send a RDMA read response or atomic operation.
 226  */
 227 struct rvt_ack_entry {
 228         struct rvt_sge rdma_sge;
 229         u64 atomic_data;
 230         u32 psn;
 231         u32 lpsn;
 232         u8 opcode;
 233         u8 sent;
 234 };
 235
 236 #define RC_QP_SCALING_INTERVAL  5
 237
 238 #define RVT_OPERATION_PRIV        0x00000001
 239 #define RVT_OPERATION_ATOMIC      0x00000002
 240 #define RVT_OPERATION_ATOMIC_SGE  0x00000004
 241 #define RVT_OPERATION_LOCAL       0x00000008
 242 #define RVT_OPERATION_USE_RESERVE 0x00000010
 243
 244 #define RVT_OPERATION_MAX (IB_WR_RESERVED10 + 1)
 245
 246 /**
 247  * rvt_operation_params - op table entry
 248  * @length - the length to copy into the swqe entry
 249  * @qpt_support - a bit mask indicating QP type support
 250  * @flags - RVT_OPERATION flags (see above)
 251  *
 252  * This supports table driven post send so that
 253  * the driver can have differing an potentially
 254  * different sets of operations.
 255  *
 256  **/
 257
 258 struct rvt_operation_params {
 259         size_t length;
 260         u32 qpt_support;
 261         u32 flags;
 262 };
 263
 264 /*
 265  * Common variables are protected by both r_rq.lock and s_lock in that order
 266  * which only happens in modify_qp() or changing the QP 'state'.
 267  */
 268 struct rvt_qp {
 269         struct ib_qp ibqp;
 270         void *priv; /* Driver private data */
 271         /* read mostly fields above and below */
 272         struct rdma_ah_attr remote_ah_attr;
 273         struct rdma_ah_attr alt_ah_attr;
 274         struct rvt_qp __rcu *next;           /* link list for QPN hash table */
 275         struct rvt_swqe *s_wq;  /* send work queue */
 276         struct rvt_mmap_info *ip;
 277
 278         unsigned long timeout_jiffies;  /* computed from timeout */
 279
 280         int srate_mbps;         /* s_srate (below) converted to Mbit/s */
 281         pid_t pid;              /* pid for user mode QPs */
 282         u32 remote_qpn;
 283         u32 qkey;               /* QKEY for this QP (for UD or RD) */
 284         u32 s_size;             /* send work queue size */
 285         u32 s_ahgpsn;           /* set to the psn in the copy of the header */
 286
 287         u16 pmtu;               /* decoded from path_mtu */
 288         u8 log_pmtu;            /* shift for pmtu */
 289         u8 state;               /* QP state */
 290         u8 allowed_ops;         /* high order bits of allowed opcodes */
 291         u8 qp_access_flags;
 292         u8 alt_timeout;         /* Alternate path timeout for this QP */
 293         u8 timeout;             /* Timeout for this QP */
 294         u8 s_srate;
 295         u8 s_mig_state;
 296         u8 port_num;
 297         u8 s_pkey_index;        /* PKEY index to use */
 298         u8 s_alt_pkey_index;    /* Alternate path PKEY index to use */
 299         u8 r_max_rd_atomic;     /* max number of RDMA read/atomic to receive */
 300         u8 s_max_rd_atomic;     /* max number of RDMA read/atomic to send */
 301         u8 s_retry_cnt;         /* number of times to retry */
 302         u8 s_rnr_retry_cnt;
 303         u8 r_min_rnr_timer;     /* retry timeout value for RNR NAKs */
 304         u8 s_max_sge;           /* size of s_wq->sg_list */
 305         u8 s_draining;
 306
 307         /* start of read/write fields */
 308         atomic_t refcount ____cacheline_aligned_in_smp;
 309         wait_queue_head_t wait;
 310
 311         struct rvt_ack_entry *s_ack_queue;
 312         struct rvt_sge_state s_rdma_read_sge;
 313
 314         spinlock_t r_lock ____cacheline_aligned_in_smp;      /* used for APM */
 315         u32 r_psn;              /* expected rcv packet sequence number */
 316         unsigned long r_aflags;
 317         u64 r_wr_id;            /* ID for current receive WQE */
 318         u32 r_ack_psn;          /* PSN for next ACK or atomic ACK */
 319         u32 r_len;              /* total length of r_sge */
 320         u32 r_rcv_len;          /* receive data len processed */
 321         u32 r_msn;              /* message sequence number */
 322
 323         u8 r_state;             /* opcode of last packet received */
 324         u8 r_flags;
 325         u8 r_head_ack_queue;    /* index into s_ack_queue[] */
 326         u8 r_adefered;          /* defered ack count */
 327
 328         struct list_head rspwait;       /* link for waiting to respond */
 329
 330         struct rvt_sge_state r_sge;     /* current receive data */
 331         struct rvt_rq r_rq;             /* receive work queue */
 332
 333         /* post send line */
 334         spinlock_t s_hlock ____cacheline_aligned_in_smp;
 335         u32 s_head;             /* new entries added here */
 336         u32 s_next_psn;         /* PSN for next request */
 337         u32 s_avail;            /* number of entries avail */
 338         u32 s_ssn;              /* SSN of tail entry */
 339         atomic_t s_reserved_used; /* reserved entries in use */
 340
 341         spinlock_t s_lock ____cacheline_aligned_in_smp;
 342         u32 s_flags;
 343         struct rvt_sge_state *s_cur_sge;
 344         struct rvt_swqe *s_wqe;
 345         struct rvt_sge_state s_sge;     /* current send request data */
 346         struct rvt_mregion *s_rdma_mr;
 347         u32 s_cur_size;         /* size of send packet in bytes */
 348         u32 s_len;              /* total length of s_sge */
 349         u32 s_rdma_read_len;    /* total length of s_rdma_read_sge */
 350         u32 s_last_psn;         /* last response PSN processed */
 351         u32 s_sending_psn;      /* lowest PSN that is being sent */
 352         u32 s_sending_hpsn;     /* highest PSN that is being sent */
 353         u32 s_psn;              /* current packet sequence number */
 354         u32 s_ack_rdma_psn;     /* PSN for sending RDMA read responses */
 355         u32 s_ack_psn;          /* PSN for acking sends and RDMA writes */
 356         u32 s_tail;             /* next entry to process */
 357         u32 s_cur;              /* current work queue entry */
 358         u32 s_acked;            /* last un-ACK'ed entry */
 359         u32 s_last;             /* last completed entry */
 360         u32 s_lsn;              /* limit sequence number (credit) */
 361         u16 s_hdrwords;         /* size of s_hdr in 32 bit words */
 362         u16 s_rdma_ack_cnt;
 363         s8 s_ahgidx;
 364         u8 s_state;             /* opcode of last packet sent */
 365         u8 s_ack_state;         /* opcode of packet to ACK */
 366         u8 s_nak_state;         /* non-zero if NAK is pending */
 367         u8 r_nak_state;         /* non-zero if NAK is pending */
 368         u8 s_retry;             /* requester retry counter */
 369         u8 s_rnr_retry;         /* requester RNR retry counter */
 370         u8 s_num_rd_atomic;     /* number of RDMA read/atomic pending */
 371         u8 s_tail_ack_queue;    /* index into s_ack_queue[] */
 372
 373         struct rvt_sge_state s_ack_rdma_sge;
 374         struct timer_list s_timer;
 375         struct hrtimer s_rnr_timer;
 376
 377         atomic_t local_ops_pending; /* number of fast_reg/local_inv reqs */
 378
 379         /*
 380          * This sge list MUST be last. Do not add anything below here.
 381          */
 382         struct rvt_sge r_sg_list[0] /* verified SGEs */
 383                 ____cacheline_aligned_in_smp;
 384 };
 385
 386 struct rvt_srq {
 387         struct ib_srq ibsrq;
 388         struct rvt_rq rq;
 389         struct rvt_mmap_info *ip;
 390         /* send signal when number of RWQEs < limit */
 391         u32 limit;
 392 };
 393
 394 #define RVT_QPN_MAX                 BIT(24)
 395 #define RVT_QPNMAP_ENTRIES          (RVT_QPN_MAX / PAGE_SIZE / BITS_PER_BYTE)
 396 #define RVT_BITS_PER_PAGE           (PAGE_SIZE * BITS_PER_BYTE)
 397 #define RVT_BITS_PER_PAGE_MASK      (RVT_BITS_PER_PAGE - 1)
 398 #define RVT_QPN_MASK                IB_QPN_MASK
 399
 400 /*
 401  * QPN-map pages start out as NULL, they get allocated upon
 402  * first use and are never deallocated. This way,
 403  * large bitmaps are not allocated unless large numbers of QPs are used.
 404  */
 405 struct rvt_qpn_map {
 406         void *page;
 407 };
 408
 409 struct rvt_qpn_table {
 410         spinlock_t lock; /* protect changes to the qp table */
 411         unsigned flags;         /* flags for QP0/1 allocated for each port */
 412         u32 last;               /* last QP number allocated */
 413         u32 nmaps;              /* size of the map table */
 414         u16 limit;
 415         u8  incr;
 416         /* bit map of free QP numbers other than 0/1 */
 417         struct rvt_qpn_map map[RVT_QPNMAP_ENTRIES];
 418 };
 419
 420 struct rvt_qp_ibdev {
 421         u32 qp_table_size;
 422         u32 qp_table_bits;
 423         struct rvt_qp __rcu **qp_table;
 424         spinlock_t qpt_lock; /* qptable lock */
 425         struct rvt_qpn_table qpn_table;
 426 };
 427
 428 /*
 429  * There is one struct rvt_mcast for each multicast GID.
 430  * All attached QPs are then stored as a list of
 431  * struct rvt_mcast_qp.
 432  */
 433 struct rvt_mcast_qp {
 434         struct list_head list;
 435         struct rvt_qp *qp;
 436 };
 437
 438 struct rvt_mcast_addr {
 439         union ib_gid mgid;
 440         u16 lid;
 441 };
 442
 443 struct rvt_mcast {
 444         struct rb_node rb_node;
 445         struct rvt_mcast_addr mcast_addr;
 446         struct list_head qp_list;
 447         wait_queue_head_t wait;
 448         atomic_t refcount;
 449         int n_attached;
 450 };
 451
 452 /*
 453  * Since struct rvt_swqe is not a fixed size, we can't simply index into
 454  * struct rvt_qp.s_wq.  This function does the array index computation.
 455  */
 456 static inline struct rvt_swqe *rvt_get_swqe_ptr(struct rvt_qp *qp,
 457                                                 unsigned n)
 458 {
 459         return (struct rvt_swqe *)((char *)qp->s_wq +
 460                                      (sizeof(struct rvt_swqe) +
 461                                       qp->s_max_sge *
 462                                       sizeof(struct rvt_sge)) * n);
 463 }
 464
 465 /*
 466  * Since struct rvt_rwqe is not a fixed size, we can't simply index into
 467  * struct rvt_rwq.wq.  This function does the array index computation.
 468  */
 469 static inline struct rvt_rwqe *rvt_get_rwqe_ptr(struct rvt_rq *rq, unsigned n)
 470 {
 471         return (struct rvt_rwqe *)
 472                 ((char *)rq->wq->wq +
 473                  (sizeof(struct rvt_rwqe) +
 474                   rq->max_sge * sizeof(struct ib_sge)) * n);
 475 }
 476
 477 /**
 478  * rvt_is_user_qp - return if this is user mode QP
 479  * @qp - the target QP
 480  */
 481 static inline bool rvt_is_user_qp(struct rvt_qp *qp)
 482 {
 483         return !!qp->pid;
 484 }
 485
 486 /**
 487  * rvt_get_qp - get a QP reference
 488  * @qp - the QP to hold
 489  */
 490 static inline void rvt_get_qp(struct rvt_qp *qp)
 491 {
 492         atomic_inc(&qp->refcount);
 493 }
 494
 495 /**
 496  * rvt_put_qp - release a QP reference
 497  * @qp - the QP to release
 498  */
 499 static inline void rvt_put_qp(struct rvt_qp *qp)
 500 {
 501         if (qp && atomic_dec_and_test(&qp->refcount))
 502                 wake_up(&qp->wait);
 503 }
 504
 505 /**
 506  * rvt_put_swqe - drop mr refs held by swqe
 507  * @wqe - the send wqe
 508  *
 509  * This drops any mr references held by the swqe
 510  */
 511 static inline void rvt_put_swqe(struct rvt_swqe *wqe)
 512 {
 513         int i;
 514
 515         for (i = 0; i < wqe->wr.num_sge; i++) {
 516                 struct rvt_sge *sge = &wqe->sg_list[i];
 517
 518                 rvt_put_mr(sge->mr);
 519         }
 520 }
 521
 522 /**
 523  * rvt_qp_wqe_reserve - reserve operation
 524  * @qp - the rvt qp
 525  * @wqe - the send wqe
 526  *
 527  * This routine used in post send to record
 528  * a wqe relative reserved operation use.
 529  */
 530 static inline void rvt_qp_wqe_reserve(
 531         struct rvt_qp *qp,
 532         struct rvt_swqe *wqe)
 533 {
 534         atomic_inc(&qp->s_reserved_used);
 535 }
 536
 537 /**
 538  * rvt_qp_wqe_unreserve - clean reserved operation
 539  * @qp - the rvt qp
 540  * @wqe - the send wqe
 541  *
 542  * This decrements the reserve use count.
 543  *
 544  * This call MUST precede the change to
 545  * s_last to insure that post send sees a stable
 546  * s_avail.
 547  *
 548  * An smp_mp__after_atomic() is used to insure
 549  * the compiler does not juggle the order of the s_last
 550  * ring index and the decrementing of s_reserved_used.
 551  */
 552 static inline void rvt_qp_wqe_unreserve(
 553         struct rvt_qp *qp,
 554         struct rvt_swqe *wqe)
 555 {
 556         if (unlikely(wqe->wr.send_flags & RVT_SEND_RESERVE_USED)) {
 557                 atomic_dec(&qp->s_reserved_used);
 558                 /* insure no compiler re-order up to s_last change */
 559                 smp_mb__after_atomic();
 560         }
 561 }
 562
 563 extern const enum ib_wc_opcode ib_rvt_wc_opcode[];
 564
 565 /**
 566  * rvt_qp_swqe_complete() - insert send completion
 567  * @qp - the qp
 568  * @wqe - the send wqe
 569  * @status - completion status
 570  *
 571  * Insert a send completion into the completion
 572  * queue if the qp indicates it should be done.
 573  *
 574  * See IBTA 10.7.3.1 for info on completion
 575  * control.
 576  */
 577 static inline void rvt_qp_swqe_complete(
 578         struct rvt_qp *qp,
 579         struct rvt_swqe *wqe,
 580         enum ib_wc_opcode opcode,
 581         enum ib_wc_status status)
 582 {
 583         if (unlikely(wqe->wr.send_flags & RVT_SEND_RESERVE_USED))
 584                 return;
 585         if (!(qp->s_flags & RVT_S_SIGNAL_REQ_WR) ||
 586             (wqe->wr.send_flags & IB_SEND_SIGNALED) ||
 587              status != IB_WC_SUCCESS) {
 588                 struct ib_wc wc;
 589
 590                 memset(&wc, 0, sizeof(wc));
 591                 wc.wr_id = wqe->wr.wr_id;
 592                 wc.status = status;
 593                 wc.opcode = opcode;
 594                 wc.qp = &qp->ibqp;
 595                 wc.byte_len = wqe->length;
 596                 rvt_cq_enter(ibcq_to_rvtcq(qp->ibqp.send_cq), &wc,
 597                              status != IB_WC_SUCCESS);
 598         }
 599 }
 600
 601 /*
 602  * Compare the lower 24 bits of the msn values.
 603  * Returns an integer <, ==, or > than zero.
 604  */
 605 static inline int rvt_cmp_msn(u32 a, u32 b)
 606 {
 607         return (((int)a) - ((int)b)) << 8;
 608 }
 609
 610 /**
 611  * rvt_compute_aeth - compute the AETH (syndrome + MSN)
 612  * @qp: the queue pair to compute the AETH for
 613  *
 614  * Returns the AETH.
 615  */
 616 __be32 rvt_compute_aeth(struct rvt_qp *qp);
 617
 618 /**
 619  * rvt_get_credit - flush the send work queue of a QP
 620  * @qp: the qp who's send work queue to flush
 621  * @aeth: the Acknowledge Extended Transport Header
 622  *
 623  * The QP s_lock should be held.
 624  */
 625 void rvt_get_credit(struct rvt_qp *qp, u32 aeth);
 626
 627 /**
 628  * @qp - the qp pair
 629  * @len - the length
 630  *
 631  * Perform a shift based mtu round up divide
 632  */
 633 static inline u32 rvt_div_round_up_mtu(struct rvt_qp *qp, u32 len)
 634 {
 635         return (len + qp->pmtu - 1) >> qp->log_pmtu;
 636 }
 637
 638 /**
 639  * @qp - the qp pair
 640  * @len - the length
 641  *
 642  * Perform a shift based mtu divide
 643  */
 644 static inline u32 rvt_div_mtu(struct rvt_qp *qp, u32 len)
 645 {
 646         return len >> qp->log_pmtu;
 647 }
 648
 649 /**
 650  * rvt_timeout_to_jiffies - Convert a ULP timeout input into jiffies
 651  * @timeout - timeout input(0 - 31).
 652  *
 653  * Return a timeout value in jiffies.
 654  */
 655 static inline unsigned long rvt_timeout_to_jiffies(u8 timeout)
 656 {
 657         if (timeout > 31)
 658                 timeout = 31;
 659
 660         return usecs_to_jiffies(1U << timeout) * 4096UL / 1000UL;
 661 }
 662
 663 extern const int  ib_rvt_state_ops[];
 664
 665 struct rvt_dev_info;
 666 void rvt_comm_est(struct rvt_qp *qp);
 667 int rvt_error_qp(struct rvt_qp *qp, enum ib_wc_status err);
 668 void rvt_rc_error(struct rvt_qp *qp, enum ib_wc_status err);
 669 unsigned long rvt_rnr_tbl_to_usec(u32 index);
 670 enum hrtimer_restart rvt_rc_rnr_retry(struct hrtimer *t);
 671 void rvt_add_rnr_timer(struct rvt_qp *qp, u32 aeth);
 672 void rvt_del_timers_sync(struct rvt_qp *qp);
 673 void rvt_stop_rc_timers(struct rvt_qp *qp);
 674 void rvt_add_retry_timer(struct rvt_qp *qp);
 675
 676 /**
 677  * struct rvt_qp_iter - the iterator for QPs
 678  * @qp - the current QP
 679  *
 680  * This structure defines the current iterator
 681  * state for sequenced access to all QPs relative
 682  * to an rvt_dev_info.
 683  */
 684 struct rvt_qp_iter {
 685         struct rvt_qp *qp;
 686         /* private: backpointer */
 687         struct rvt_dev_info *rdi;
 688         /* private: callback routine */
 689         void (*cb)(struct rvt_qp *qp, u64 v);
 690         /* private: for arg to callback routine */
 691         u64 v;
 692         /* private: number of SMI,GSI QPs for device */
 693         int specials;
 694         /* private: current iterator index */
 695         int n;
 696 };
 697
 698 struct rvt_qp_iter *rvt_qp_iter_init(struct rvt_dev_info *rdi,
 699                                      u64 v,
 700                                      void (*cb)(struct rvt_qp *qp, u64 v));
 701 int rvt_qp_iter_next(struct rvt_qp_iter *iter);
 702 void rvt_qp_iter(struct rvt_dev_info *rdi,
 703                  u64 v,
 704                  void (*cb)(struct rvt_qp *qp, u64 v));
 705 void rvt_qp_mr_clean(struct rvt_qp *qp, u32 lkey);
 706 #endif          /* DEF_RDMAVT_INCQP_H */