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  * Send work request queue entry.
 149  * The size of the sg_list is determined when the QP is created and stored
 150  * in qp->s_max_sge.
 151  */
 152 struct rvt_swqe {
 153         union {
 154                 struct ib_send_wr wr;   /* don't use wr.sg_list */
 155                 struct ib_ud_wr ud_wr;
 156                 struct ib_reg_wr reg_wr;
 157                 struct ib_rdma_wr rdma_wr;
 158                 struct ib_atomic_wr atomic_wr;
 159         };
 160         u32 psn;                /* first packet sequence number */
 161         u32 lpsn;               /* last packet sequence number */
 162         u32 ssn;                /* send sequence number */
 163         u32 length;             /* total length of data in sg_list */
 164         struct rvt_sge sg_list[0];
 165 };
 166
 167 /*
 168  * Receive work request queue entry.
 169  * The size of the sg_list is determined when the QP (or SRQ) is created
 170  * and stored in qp->r_rq.max_sge (or srq->rq.max_sge).
 171  */
 172 struct rvt_rwqe {
 173         u64 wr_id;
 174         u8 num_sge;
 175         struct ib_sge sg_list[0];
 176 };
 177
 178 /*
 179  * This structure is used to contain the head pointer, tail pointer,
 180  * and receive work queue entries as a single memory allocation so
 181  * it can be mmap'ed into user space.
 182  * Note that the wq array elements are variable size so you can't
 183  * just index into the array to get the N'th element;
 184  * use get_rwqe_ptr() instead.
 185  */
 186 struct rvt_rwq {
 187         u32 head;               /* new work requests posted to the head */
 188         u32 tail;               /* receives pull requests from here. */
 189         struct rvt_rwqe wq[0];
 190 };
 191
 192 struct rvt_rq {
 193         struct rvt_rwq *wq;
 194         u32 size;               /* size of RWQE array */
 195         u8 max_sge;
 196         /* protect changes in this struct */
 197         spinlock_t lock ____cacheline_aligned_in_smp;
 198 };
 199
 200 /*
 201  * This structure is used by rvt_mmap() to validate an offset
 202  * when an mmap() request is made.  The vm_area_struct then uses
 203  * this as its vm_private_data.
 204  */
 205 struct rvt_mmap_info {
 206         struct list_head pending_mmaps;
 207         struct ib_ucontext *context;
 208         void *obj;
 209         __u64 offset;
 210         struct kref ref;
 211         unsigned size;
 212 };
 213
 214 #define RVT_MAX_RDMA_ATOMIC     16
 215
 216 /*
 217  * This structure holds the information that the send tasklet needs
 218  * to send a RDMA read response or atomic operation.
 219  */
 220 struct rvt_ack_entry {
 221         u8 opcode;
 222         u8 sent;
 223         u32 psn;
 224         u32 lpsn;
 225         union {
 226                 struct rvt_sge rdma_sge;
 227                 u64 atomic_data;
 228         };
 229 };
 230
 231 #define RC_QP_SCALING_INTERVAL  5
 232
 233 /*
 234  * Variables prefixed with s_ are for the requester (sender).
 235  * Variables prefixed with r_ are for the responder (receiver).
 236  * Variables prefixed with ack_ are for responder replies.
 237  *
 238  * Common variables are protected by both r_rq.lock and s_lock in that order
 239  * which only happens in modify_qp() or changing the QP 'state'.
 240  */
 241 struct rvt_qp {
 242         struct ib_qp ibqp;
 243         void *priv; /* Driver private data */
 244         /* read mostly fields above and below */
 245         struct ib_ah_attr remote_ah_attr;
 246         struct ib_ah_attr alt_ah_attr;
 247         struct rvt_qp __rcu *next;           /* link list for QPN hash table */
 248         struct rvt_swqe *s_wq;  /* send work queue */
 249         struct rvt_mmap_info *ip;
 250
 251         unsigned long timeout_jiffies;  /* computed from timeout */
 252
 253         enum ib_mtu path_mtu;
 254         int srate_mbps;         /* s_srate (below) converted to Mbit/s */
 255         pid_t pid;              /* pid for user mode QPs */
 256         u32 remote_qpn;
 257         u32 qkey;               /* QKEY for this QP (for UD or RD) */
 258         u32 s_size;             /* send work queue size */
 259         u32 s_ahgpsn;           /* set to the psn in the copy of the header */
 260
 261         u16 pmtu;               /* decoded from path_mtu */
 262         u8 log_pmtu;            /* shift for pmtu */
 263         u8 state;               /* QP state */
 264         u8 allowed_ops;         /* high order bits of allowed opcodes */
 265         u8 qp_access_flags;
 266         u8 alt_timeout;         /* Alternate path timeout for this QP */
 267         u8 timeout;             /* Timeout for this QP */
 268         u8 s_srate;
 269         u8 s_mig_state;
 270         u8 port_num;
 271         u8 s_pkey_index;        /* PKEY index to use */
 272         u8 s_alt_pkey_index;    /* Alternate path PKEY index to use */
 273         u8 r_max_rd_atomic;     /* max number of RDMA read/atomic to receive */
 274         u8 s_max_rd_atomic;     /* max number of RDMA read/atomic to send */
 275         u8 s_retry_cnt;         /* number of times to retry */
 276         u8 s_rnr_retry_cnt;
 277         u8 r_min_rnr_timer;     /* retry timeout value for RNR NAKs */
 278         u8 s_max_sge;           /* size of s_wq->sg_list */
 279         u8 s_draining;
 280
 281         /* start of read/write fields */
 282         atomic_t refcount ____cacheline_aligned_in_smp;
 283         wait_queue_head_t wait;
 284
 285         struct rvt_ack_entry s_ack_queue[RVT_MAX_RDMA_ATOMIC + 1]
 286                 ____cacheline_aligned_in_smp;
 287         struct rvt_sge_state s_rdma_read_sge;
 288
 289         spinlock_t r_lock ____cacheline_aligned_in_smp;      /* used for APM */
 290         u32 r_psn;              /* expected rcv packet sequence number */
 291         unsigned long r_aflags;
 292         u64 r_wr_id;            /* ID for current receive WQE */
 293         u32 r_ack_psn;          /* PSN for next ACK or atomic ACK */
 294         u32 r_len;              /* total length of r_sge */
 295         u32 r_rcv_len;          /* receive data len processed */
 296         u32 r_msn;              /* message sequence number */
 297
 298         u8 r_state;             /* opcode of last packet received */
 299         u8 r_flags;
 300         u8 r_head_ack_queue;    /* index into s_ack_queue[] */
 301
 302         struct list_head rspwait;       /* link for waiting to respond */
 303
 304         struct rvt_sge_state r_sge;     /* current receive data */
 305         struct rvt_rq r_rq;             /* receive work queue */
 306
 307         /* post send line */
 308         spinlock_t s_hlock ____cacheline_aligned_in_smp;
 309         u32 s_head;             /* new entries added here */
 310         u32 s_next_psn;         /* PSN for next request */
 311         u32 s_avail;            /* number of entries avail */
 312         u32 s_ssn;              /* SSN of tail entry */
 313
 314         spinlock_t s_lock ____cacheline_aligned_in_smp;
 315         u32 s_flags;
 316         struct rvt_sge_state *s_cur_sge;
 317         struct rvt_swqe *s_wqe;
 318         struct rvt_sge_state s_sge;     /* current send request data */
 319         struct rvt_mregion *s_rdma_mr;
 320         u32 s_cur_size;         /* size of send packet in bytes */
 321         u32 s_len;              /* total length of s_sge */
 322         u32 s_rdma_read_len;    /* total length of s_rdma_read_sge */
 323         u32 s_last_psn;         /* last response PSN processed */
 324         u32 s_sending_psn;      /* lowest PSN that is being sent */
 325         u32 s_sending_hpsn;     /* highest PSN that is being sent */
 326         u32 s_psn;              /* current packet sequence number */
 327         u32 s_ack_rdma_psn;     /* PSN for sending RDMA read responses */
 328         u32 s_ack_psn;          /* PSN for acking sends and RDMA writes */
 329         u32 s_tail;             /* next entry to process */
 330         u32 s_cur;              /* current work queue entry */
 331         u32 s_acked;            /* last un-ACK'ed entry */
 332         u32 s_last;             /* last completed entry */
 333         u32 s_lsn;              /* limit sequence number (credit) */
 334         u16 s_hdrwords;         /* size of s_hdr in 32 bit words */
 335         u16 s_rdma_ack_cnt;
 336         s8 s_ahgidx;
 337         u8 s_state;             /* opcode of last packet sent */
 338         u8 s_ack_state;         /* opcode of packet to ACK */
 339         u8 s_nak_state;         /* non-zero if NAK is pending */
 340         u8 r_nak_state;         /* non-zero if NAK is pending */
 341         u8 s_retry;             /* requester retry counter */
 342         u8 s_rnr_retry;         /* requester RNR retry counter */
 343         u8 s_num_rd_atomic;     /* number of RDMA read/atomic pending */
 344         u8 s_tail_ack_queue;    /* index into s_ack_queue[] */
 345
 346         struct rvt_sge_state s_ack_rdma_sge;
 347         struct timer_list s_timer;
 348
 349         /*
 350          * This sge list MUST be last. Do not add anything below here.
 351          */
 352         struct rvt_sge r_sg_list[0] /* verified SGEs */
 353                 ____cacheline_aligned_in_smp;
 354 };
 355
 356 struct rvt_srq {
 357         struct ib_srq ibsrq;
 358         struct rvt_rq rq;
 359         struct rvt_mmap_info *ip;
 360         /* send signal when number of RWQEs < limit */
 361         u32 limit;
 362 };
 363
 364 #define RVT_QPN_MAX                 BIT(24)
 365 #define RVT_QPNMAP_ENTRIES          (RVT_QPN_MAX / PAGE_SIZE / BITS_PER_BYTE)
 366 #define RVT_BITS_PER_PAGE           (PAGE_SIZE * BITS_PER_BYTE)
 367 #define RVT_BITS_PER_PAGE_MASK      (RVT_BITS_PER_PAGE - 1)
 368 #define RVT_QPN_MASK                0xFFFFFF
 369
 370 /*
 371  * QPN-map pages start out as NULL, they get allocated upon
 372  * first use and are never deallocated. This way,
 373  * large bitmaps are not allocated unless large numbers of QPs are used.
 374  */
 375 struct rvt_qpn_map {
 376         void *page;
 377 };
 378
 379 struct rvt_qpn_table {
 380         spinlock_t lock; /* protect changes to the qp table */
 381         unsigned flags;         /* flags for QP0/1 allocated for each port */
 382         u32 last;               /* last QP number allocated */
 383         u32 nmaps;              /* size of the map table */
 384         u16 limit;
 385         u8  incr;
 386         /* bit map of free QP numbers other than 0/1 */
 387         struct rvt_qpn_map map[RVT_QPNMAP_ENTRIES];
 388 };
 389
 390 struct rvt_qp_ibdev {
 391         u32 qp_table_size;
 392         u32 qp_table_bits;
 393         struct rvt_qp __rcu **qp_table;
 394         spinlock_t qpt_lock; /* qptable lock */
 395         struct rvt_qpn_table qpn_table;
 396 };
 397
 398 /*
 399  * There is one struct rvt_mcast for each multicast GID.
 400  * All attached QPs are then stored as a list of
 401  * struct rvt_mcast_qp.
 402  */
 403 struct rvt_mcast_qp {
 404         struct list_head list;
 405         struct rvt_qp *qp;
 406 };
 407
 408 struct rvt_mcast {
 409         struct rb_node rb_node;
 410         union ib_gid mgid;
 411         struct list_head qp_list;
 412         wait_queue_head_t wait;
 413         atomic_t refcount;
 414         int n_attached;
 415 };
 416
 417 /*
 418  * Since struct rvt_swqe is not a fixed size, we can't simply index into
 419  * struct rvt_qp.s_wq.  This function does the array index computation.
 420  */
 421 static inline struct rvt_swqe *rvt_get_swqe_ptr(struct rvt_qp *qp,
 422                                                 unsigned n)
 423 {
 424         return (struct rvt_swqe *)((char *)qp->s_wq +
 425                                      (sizeof(struct rvt_swqe) +
 426                                       qp->s_max_sge *
 427                                       sizeof(struct rvt_sge)) * n);
 428 }
 429
 430 /*
 431  * Since struct rvt_rwqe is not a fixed size, we can't simply index into
 432  * struct rvt_rwq.wq.  This function does the array index computation.
 433  */
 434 static inline struct rvt_rwqe *rvt_get_rwqe_ptr(struct rvt_rq *rq, unsigned n)
 435 {
 436         return (struct rvt_rwqe *)
 437                 ((char *)rq->wq->wq +
 438                  (sizeof(struct rvt_rwqe) +
 439                   rq->max_sge * sizeof(struct ib_sge)) * n);
 440 }
 441
 442 extern const int  ib_rvt_state_ops[];
 443
 444 struct rvt_dev_info;
 445 int rvt_error_qp(struct rvt_qp *qp, enum ib_wc_status err);
 446
 447 #endif          /* DEF_RDMAVT_INCQP_H */