include/rdma/rdmavt_qp.h

   1 #ifndef DEF_RDMAVT_INCQP_H
   2 #define DEF_RDMAVT_INCQP_H
   3
   4 /*
   5  * Copyright(c) 2016 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 /*
  55  * Atomic bit definitions for r_aflags.
  56  */
  57 #define RVT_R_WRID_VALID        0
  58 #define RVT_R_REWIND_SGE        1
  59
  60 /*
  61  * Bit definitions for r_flags.
  62  */
  63 #define RVT_R_REUSE_SGE 0x01
  64 #define RVT_R_RDMAR_SEQ 0x02
  65 #define RVT_R_RSP_NAK   0x04
  66 #define RVT_R_RSP_SEND  0x08
  67 #define RVT_R_COMM_EST  0x10
  68
  69 /*
  70  * Bit definitions for s_flags.
  71  *
  72  * RVT_S_SIGNAL_REQ_WR - set if QP send WRs contain completion signaled
  73  * RVT_S_BUSY - send tasklet is processing the QP
  74  * RVT_S_TIMER - the RC retry timer is active
  75  * RVT_S_ACK_PENDING - an ACK is waiting to be sent after RDMA read/atomics
  76  * RVT_S_WAIT_FENCE - waiting for all prior RDMA read or atomic SWQEs
  77  *                         before processing the next SWQE
  78  * RVT_S_WAIT_RDMAR - waiting for a RDMA read or atomic SWQE to complete
  79  *                         before processing the next SWQE
  80  * RVT_S_WAIT_RNR - waiting for RNR timeout
  81  * RVT_S_WAIT_SSN_CREDIT - waiting for RC credits to process next SWQE
  82  * RVT_S_WAIT_DMA - waiting for send DMA queue to drain before generating
  83  *                  next send completion entry not via send DMA
  84  * RVT_S_WAIT_PIO - waiting for a send buffer to be available
  85  * RVT_S_WAIT_PIO_DRAIN - waiting for a qp to drain pio packets
  86  * RVT_S_WAIT_TX - waiting for a struct verbs_txreq to be available
  87  * RVT_S_WAIT_DMA_DESC - waiting for DMA descriptors to be available
  88  * RVT_S_WAIT_KMEM - waiting for kernel memory to be available
  89  * RVT_S_WAIT_PSN - waiting for a packet to exit the send DMA queue
  90  * RVT_S_WAIT_ACK - waiting for an ACK packet before sending more requests
  91  * RVT_S_SEND_ONE - send one packet, request ACK, then wait for ACK
  92  * RVT_S_ECN - a BECN was queued to the send engine
  93  */
  94 #define RVT_S_SIGNAL_REQ_WR     0x0001
  95 #define RVT_S_BUSY              0x0002
  96 #define RVT_S_TIMER             0x0004
  97 #define RVT_S_RESP_PENDING      0x0008
  98 #define RVT_S_ACK_PENDING       0x0010
  99 #define RVT_S_WAIT_FENCE        0x0020
 100 #define RVT_S_WAIT_RDMAR        0x0040
 101 #define RVT_S_WAIT_RNR          0x0080
 102 #define RVT_S_WAIT_SSN_CREDIT   0x0100
 103 #define RVT_S_WAIT_DMA          0x0200
 104 #define RVT_S_WAIT_PIO          0x0400
 105 #define RVT_S_WAIT_PIO_DRAIN    0x0800
 106 #define RVT_S_WAIT_TX           0x1000
 107 #define RVT_S_WAIT_DMA_DESC     0x2000
 108 #define RVT_S_WAIT_KMEM         0x4000
 109 #define RVT_S_WAIT_PSN          0x8000
 110 #define RVT_S_WAIT_ACK          0x10000
 111 #define RVT_S_SEND_ONE          0x20000
 112 #define RVT_S_UNLIMITED_CREDIT  0x40000
 113 #define RVT_S_AHG_VALID         0x80000
 114 #define RVT_S_AHG_CLEAR         0x100000
 115 #define RVT_S_ECN               0x200000
 116
 117 /*
 118  * Wait flags that would prevent any packet type from being sent.
 119  */
 120 #define RVT_S_ANY_WAIT_IO \
 121         (RVT_S_WAIT_PIO | RVT_S_WAIT_PIO_DRAIN | RVT_S_WAIT_TX | \
 122          RVT_S_WAIT_DMA_DESC | RVT_S_WAIT_KMEM)
 123
 124 /*
 125  * Wait flags that would prevent send work requests from making progress.
 126  */
 127 #define RVT_S_ANY_WAIT_SEND (RVT_S_WAIT_FENCE | RVT_S_WAIT_RDMAR | \
 128         RVT_S_WAIT_RNR | RVT_S_WAIT_SSN_CREDIT | RVT_S_WAIT_DMA | \
 129         RVT_S_WAIT_PSN | RVT_S_WAIT_ACK)
 130
 131 #define RVT_S_ANY_WAIT (RVT_S_ANY_WAIT_IO | RVT_S_ANY_WAIT_SEND)
 132
 133 /* Number of bits to pay attention to in the opcode for checking qp type */
 134 #define RVT_OPCODE_QP_MASK 0xE0
 135
 136 /* Flags for checking QP state (see ib_rvt_state_ops[]) */
 137 #define RVT_POST_SEND_OK                0x01
 138 #define RVT_POST_RECV_OK                0x02
 139 #define RVT_PROCESS_RECV_OK             0x04
 140 #define RVT_PROCESS_SEND_OK             0x08
 141 #define RVT_PROCESS_NEXT_SEND_OK        0x10
 142 #define RVT_FLUSH_SEND                  0x20
 143 #define RVT_FLUSH_RECV                  0x40
 144 #define RVT_PROCESS_OR_FLUSH_SEND \
 145         (RVT_PROCESS_SEND_OK | RVT_FLUSH_SEND)
 146
 147 /*
 148  * Internal send flags
 149  */
 150 #define RVT_SEND_RESERVE_USED           IB_SEND_RESERVED_START
 151 #define RVT_SEND_COMPLETION_ONLY        (IB_SEND_RESERVED_START << 1)
 152
 153 /*
 154  * Send work request queue entry.
 155  * The size of the sg_list is determined when the QP is created and stored
 156  * in qp->s_max_sge.
 157  */
 158 struct rvt_swqe {
 159         union {
 160                 struct ib_send_wr wr;   /* don't use wr.sg_list */
 161                 struct ib_ud_wr ud_wr;
 162                 struct ib_reg_wr reg_wr;
 163                 struct ib_rdma_wr rdma_wr;
 164                 struct ib_atomic_wr atomic_wr;
 165         };
 166         u32 psn;                /* first packet sequence number */
 167         u32 lpsn;               /* last packet sequence number */
 168         u32 ssn;                /* send sequence number */
 169         u32 length;             /* total length of data in sg_list */
 170         struct rvt_sge sg_list[0];
 171 };
 172
 173 /*
 174  * Receive work request queue entry.
 175  * The size of the sg_list is determined when the QP (or SRQ) is created
 176  * and stored in qp->r_rq.max_sge (or srq->rq.max_sge).
 177  */
 178 struct rvt_rwqe {
 179         u64 wr_id;
 180         u8 num_sge;
 181         struct ib_sge sg_list[0];
 182 };
 183
 184 /*
 185  * This structure is used to contain the head pointer, tail pointer,
 186  * and receive work queue entries as a single memory allocation so
 187  * it can be mmap'ed into user space.
 188  * Note that the wq array elements are variable size so you can't
 189  * just index into the array to get the N'th element;
 190  * use get_rwqe_ptr() instead.
 191  */
 192 struct rvt_rwq {
 193         u32 head;               /* new work requests posted to the head */
 194         u32 tail;               /* receives pull requests from here. */
 195         struct rvt_rwqe wq[0];
 196 };
 197
 198 struct rvt_rq {
 199         struct rvt_rwq *wq;
 200         u32 size;               /* size of RWQE array */
 201         u8 max_sge;
 202         /* protect changes in this struct */
 203         spinlock_t lock ____cacheline_aligned_in_smp;
 204 };
 205
 206 /*
 207  * This structure is used by rvt_mmap() to validate an offset
 208  * when an mmap() request is made.  The vm_area_struct then uses
 209  * this as its vm_private_data.
 210  */
 211 struct rvt_mmap_info {
 212         struct list_head pending_mmaps;
 213         struct ib_ucontext *context;
 214         void *obj;
 215         __u64 offset;
 216         struct kref ref;
 217         unsigned size;
 218 };
 219
 220 /*
 221  * This structure holds the information that the send tasklet needs
 222  * to send a RDMA read response or atomic operation.
 223  */
 224 struct rvt_ack_entry {
 225         struct rvt_sge rdma_sge;
 226         u64 atomic_data;
 227         u32 psn;
 228         u32 lpsn;
 229         u8 opcode;
 230         u8 sent;
 231 };
 232
 233 #define RC_QP_SCALING_INTERVAL  5
 234
 235 #define RVT_OPERATION_PRIV        0x00000001
 236 #define RVT_OPERATION_ATOMIC      0x00000002
 237 #define RVT_OPERATION_ATOMIC_SGE  0x00000004
 238 #define RVT_OPERATION_LOCAL       0x00000008
 239 #define RVT_OPERATION_USE_RESERVE 0x00000010
 240
 241 #define RVT_OPERATION_MAX (IB_WR_RESERVED10 + 1)
 242
 243 /**
 244  * rvt_operation_params - op table entry
 245  * @length - the length to copy into the swqe entry
 246  * @qpt_support - a bit mask indicating QP type support
 247  * @flags - RVT_OPERATION flags (see above)
 248  *
 249  * This supports table driven post send so that
 250  * the driver can have differing an potentially
 251  * different sets of operations.
 252  *
 253  **/
 254
 255 struct rvt_operation_params {
 256         size_t length;
 257         u32 qpt_support;
 258         u32 flags;
 259 };
 260
 261 /*
 262  * Common variables are protected by both r_rq.lock and s_lock in that order
 263  * which only happens in modify_qp() or changing the QP 'state'.
 264  */
 265 struct rvt_qp {
 266         struct ib_qp ibqp;
 267         void *priv; /* Driver private data */
 268         /* read mostly fields above and below */
 269         struct ib_ah_attr remote_ah_attr;
 270         struct ib_ah_attr alt_ah_attr;
 271         struct rvt_qp __rcu *next;           /* link list for QPN hash table */
 272         struct rvt_swqe *s_wq;  /* send work queue */
 273         struct rvt_mmap_info *ip;
 274
 275         unsigned long timeout_jiffies;  /* computed from timeout */
 276
 277         enum ib_mtu path_mtu;
 278         int srate_mbps;         /* s_srate (below) converted to Mbit/s */
 279         pid_t pid;              /* pid for user mode QPs */
 280         u32 remote_qpn;
 281         u32 qkey;               /* QKEY for this QP (for UD or RD) */
 282         u32 s_size;             /* send work queue size */
 283         u32 s_ahgpsn;           /* set to the psn in the copy of the header */
 284
 285         u16 pmtu;               /* decoded from path_mtu */
 286         u8 log_pmtu;            /* shift for pmtu */
 287         u8 state;               /* QP state */
 288         u8 allowed_ops;         /* high order bits of allowed opcodes */
 289         u8 qp_access_flags;
 290         u8 alt_timeout;         /* Alternate path timeout for this QP */
 291         u8 timeout;             /* Timeout for this QP */
 292         u8 s_srate;
 293         u8 s_mig_state;
 294         u8 port_num;
 295         u8 s_pkey_index;        /* PKEY index to use */
 296         u8 s_alt_pkey_index;    /* Alternate path PKEY index to use */
 297         u8 r_max_rd_atomic;     /* max number of RDMA read/atomic to receive */
 298         u8 s_max_rd_atomic;     /* max number of RDMA read/atomic to send */
 299         u8 s_retry_cnt;         /* number of times to retry */
 300         u8 s_rnr_retry_cnt;
 301         u8 r_min_rnr_timer;     /* retry timeout value for RNR NAKs */
 302         u8 s_max_sge;           /* size of s_wq->sg_list */
 303         u8 s_draining;
 304
 305         /* start of read/write fields */
 306         atomic_t refcount ____cacheline_aligned_in_smp;
 307         wait_queue_head_t wait;
 308
 309         struct rvt_ack_entry *s_ack_queue;
 310         struct rvt_sge_state s_rdma_read_sge;
 311
 312         spinlock_t r_lock ____cacheline_aligned_in_smp;      /* used for APM */
 313         u32 r_psn;              /* expected rcv packet sequence number */
 314         unsigned long r_aflags;
 315         u64 r_wr_id;            /* ID for current receive WQE */
 316         u32 r_ack_psn;          /* PSN for next ACK or atomic ACK */
 317         u32 r_len;              /* total length of r_sge */
 318         u32 r_rcv_len;          /* receive data len processed */
 319         u32 r_msn;              /* message sequence number */
 320
 321         u8 r_state;             /* opcode of last packet received */
 322         u8 r_flags;
 323         u8 r_head_ack_queue;    /* index into s_ack_queue[] */
 324
 325         struct list_head rspwait;       /* link for waiting to respond */
 326
 327         struct rvt_sge_state r_sge;     /* current receive data */
 328         struct rvt_rq r_rq;             /* receive work queue */
 329
 330         /* post send line */
 331         spinlock_t s_hlock ____cacheline_aligned_in_smp;
 332         u32 s_head;             /* new entries added here */
 333         u32 s_next_psn;         /* PSN for next request */
 334         u32 s_avail;            /* number of entries avail */
 335         u32 s_ssn;              /* SSN of tail entry */
 336         atomic_t s_reserved_used; /* reserved entries in use */
 337
 338         spinlock_t s_lock ____cacheline_aligned_in_smp;
 339         u32 s_flags;
 340         struct rvt_sge_state *s_cur_sge;
 341         struct rvt_swqe *s_wqe;
 342         struct rvt_sge_state s_sge;     /* current send request data */
 343         struct rvt_mregion *s_rdma_mr;
 344         u32 s_cur_size;         /* size of send packet in bytes */
 345         u32 s_len;              /* total length of s_sge */
 346         u32 s_rdma_read_len;    /* total length of s_rdma_read_sge */
 347         u32 s_last_psn;         /* last response PSN processed */
 348         u32 s_sending_psn;      /* lowest PSN that is being sent */
 349         u32 s_sending_hpsn;     /* highest PSN that is being sent */
 350         u32 s_psn;              /* current packet sequence number */
 351         u32 s_ack_rdma_psn;     /* PSN for sending RDMA read responses */
 352         u32 s_ack_psn;          /* PSN for acking sends and RDMA writes */
 353         u32 s_tail;             /* next entry to process */
 354         u32 s_cur;              /* current work queue entry */
 355         u32 s_acked;            /* last un-ACK'ed entry */
 356         u32 s_last;             /* last completed entry */
 357         u32 s_lsn;              /* limit sequence number (credit) */
 358         u16 s_hdrwords;         /* size of s_hdr in 32 bit words */
 359         u16 s_rdma_ack_cnt;
 360         s8 s_ahgidx;
 361         u8 s_state;             /* opcode of last packet sent */
 362         u8 s_ack_state;         /* opcode of packet to ACK */
 363         u8 s_nak_state;         /* non-zero if NAK is pending */
 364         u8 r_nak_state;         /* non-zero if NAK is pending */
 365         u8 s_retry;             /* requester retry counter */
 366         u8 s_rnr_retry;         /* requester RNR retry counter */
 367         u8 s_num_rd_atomic;     /* number of RDMA read/atomic pending */
 368         u8 s_tail_ack_queue;    /* index into s_ack_queue[] */
 369
 370         struct rvt_sge_state s_ack_rdma_sge;
 371         struct timer_list s_timer;
 372
 373         atomic_t local_ops_pending; /* number of fast_reg/local_inv reqs */
 374
 375         /*
 376          * This sge list MUST be last. Do not add anything below here.
 377          */
 378         struct rvt_sge r_sg_list[0] /* verified SGEs */
 379                 ____cacheline_aligned_in_smp;
 380 };
 381
 382 struct rvt_srq {
 383         struct ib_srq ibsrq;
 384         struct rvt_rq rq;
 385         struct rvt_mmap_info *ip;
 386         /* send signal when number of RWQEs < limit */
 387         u32 limit;
 388 };
 389
 390 #define RVT_QPN_MAX                 BIT(24)
 391 #define RVT_QPNMAP_ENTRIES          (RVT_QPN_MAX / PAGE_SIZE / BITS_PER_BYTE)
 392 #define RVT_BITS_PER_PAGE           (PAGE_SIZE * BITS_PER_BYTE)
 393 #define RVT_BITS_PER_PAGE_MASK      (RVT_BITS_PER_PAGE - 1)
 394 #define RVT_QPN_MASK                0xFFFFFF
 395
 396 /*
 397  * QPN-map pages start out as NULL, they get allocated upon
 398  * first use and are never deallocated. This way,
 399  * large bitmaps are not allocated unless large numbers of QPs are used.
 400  */
 401 struct rvt_qpn_map {
 402         void *page;
 403 };
 404
 405 struct rvt_qpn_table {
 406         spinlock_t lock; /* protect changes to the qp table */
 407         unsigned flags;         /* flags for QP0/1 allocated for each port */
 408         u32 last;               /* last QP number allocated */
 409         u32 nmaps;              /* size of the map table */
 410         u16 limit;
 411         u8  incr;
 412         /* bit map of free QP numbers other than 0/1 */
 413         struct rvt_qpn_map map[RVT_QPNMAP_ENTRIES];
 414 };
 415
 416 struct rvt_qp_ibdev {
 417         u32 qp_table_size;
 418         u32 qp_table_bits;
 419         struct rvt_qp __rcu **qp_table;
 420         spinlock_t qpt_lock; /* qptable lock */
 421         struct rvt_qpn_table qpn_table;
 422 };
 423
 424 /*
 425  * There is one struct rvt_mcast for each multicast GID.
 426  * All attached QPs are then stored as a list of
 427  * struct rvt_mcast_qp.
 428  */
 429 struct rvt_mcast_qp {
 430         struct list_head list;
 431         struct rvt_qp *qp;
 432 };
 433
 434 struct rvt_mcast {
 435         struct rb_node rb_node;
 436         union ib_gid mgid;
 437         struct list_head qp_list;
 438         wait_queue_head_t wait;
 439         atomic_t refcount;
 440         int n_attached;
 441 };
 442
 443 /*
 444  * Since struct rvt_swqe is not a fixed size, we can't simply index into
 445  * struct rvt_qp.s_wq.  This function does the array index computation.
 446  */
 447 static inline struct rvt_swqe *rvt_get_swqe_ptr(struct rvt_qp *qp,
 448                                                 unsigned n)
 449 {
 450         return (struct rvt_swqe *)((char *)qp->s_wq +
 451                                      (sizeof(struct rvt_swqe) +
 452                                       qp->s_max_sge *
 453                                       sizeof(struct rvt_sge)) * n);
 454 }
 455
 456 /*
 457  * Since struct rvt_rwqe is not a fixed size, we can't simply index into
 458  * struct rvt_rwq.wq.  This function does the array index computation.
 459  */
 460 static inline struct rvt_rwqe *rvt_get_rwqe_ptr(struct rvt_rq *rq, unsigned n)
 461 {
 462         return (struct rvt_rwqe *)
 463                 ((char *)rq->wq->wq +
 464                  (sizeof(struct rvt_rwqe) +
 465                   rq->max_sge * sizeof(struct ib_sge)) * n);
 466 }
 467
 468 /**
 469  * rvt_get_qp - get a QP reference
 470  * @qp - the QP to hold
 471  */
 472 static inline void rvt_get_qp(struct rvt_qp *qp)
 473 {
 474         atomic_inc(&qp->refcount);
 475 }
 476
 477 /**
 478  * rvt_put_qp - release a QP reference
 479  * @qp - the QP to release
 480  */
 481 static inline void rvt_put_qp(struct rvt_qp *qp)
 482 {
 483         if (qp && atomic_dec_and_test(&qp->refcount))
 484                 wake_up(&qp->wait);
 485 }
 486
 487 /**
 488  * rvt_qp_wqe_reserve - reserve operation
 489  * @qp - the rvt qp
 490  * @wqe - the send wqe
 491  *
 492  * This routine used in post send to record
 493  * a wqe relative reserved operation use.
 494  */
 495 static inline void rvt_qp_wqe_reserve(
 496         struct rvt_qp *qp,
 497         struct rvt_swqe *wqe)
 498 {
 499         wqe->wr.send_flags |= RVT_SEND_RESERVE_USED;
 500         atomic_inc(&qp->s_reserved_used);
 501 }
 502
 503 /**
 504  * rvt_qp_wqe_unreserve - clean reserved operation
 505  * @qp - the rvt qp
 506  * @wqe - the send wqe
 507  *
 508  * This decrements the reserve use count.
 509  *
 510  * This call MUST precede the change to
 511  * s_last to insure that post send sees a stable
 512  * s_avail.
 513  *
 514  * An smp_mp__after_atomic() is used to insure
 515  * the compiler does not juggle the order of the s_last
 516  * ring index and the decrementing of s_reserved_used.
 517  */
 518 static inline void rvt_qp_wqe_unreserve(
 519         struct rvt_qp *qp,
 520         struct rvt_swqe *wqe)
 521 {
 522         if (unlikely(wqe->wr.send_flags & RVT_SEND_RESERVE_USED)) {
 523                 wqe->wr.send_flags &= ~RVT_SEND_RESERVE_USED;
 524                 atomic_dec(&qp->s_reserved_used);
 525                 /* insure no compiler re-order up to s_last change */
 526                 smp_mb__after_atomic();
 527         }
 528 }
 529
 530 extern const int  ib_rvt_state_ops[];
 531
 532 struct rvt_dev_info;
 533 int rvt_error_qp(struct rvt_qp *qp, enum ib_wc_status err);
 534
 535 #endif          /* DEF_RDMAVT_INCQP_H */