net/smc/smc_wr.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * Shared Memory Communications over RDMA (SMC-R) and RoCE
   4  *
   5  * Work Requests exploiting Infiniband API
   6  *
   7  * Copyright IBM Corp. 2016
   8  *
   9  * Author(s):  Steffen Maier <maier@linux.vnet.ibm.com>
  10  */
  11
  12 #ifndef SMC_WR_H
  13 #define SMC_WR_H
  14
  15 #include <linux/atomic.h>
  16 #include <rdma/ib_verbs.h>
  17 #include <asm/div64.h>
  18
  19 #include "smc.h"
  20 #include "smc_core.h"
  21
  22 #define SMC_WR_BUF_CNT 16       /* # of ctrl buffers per link */
  23
  24 #define SMC_WR_TX_WAIT_FREE_SLOT_TIME   (10 * HZ)
  25
  26 #define SMC_WR_TX_SIZE 44 /* actual size of wr_send data (<=SMC_WR_BUF_SIZE) */
  27
  28 #define SMC_WR_TX_PEND_PRIV_SIZE 32
  29
  30 struct smc_wr_tx_pend_priv {
  31         u8                      priv[SMC_WR_TX_PEND_PRIV_SIZE];
  32 };
  33
  34 typedef void (*smc_wr_tx_handler)(struct smc_wr_tx_pend_priv *,
  35                                   struct smc_link *,
  36                                   enum ib_wc_status);
  37
  38 typedef bool (*smc_wr_tx_filter)(struct smc_wr_tx_pend_priv *,
  39                                  unsigned long);
  40
  41 typedef void (*smc_wr_tx_dismisser)(struct smc_wr_tx_pend_priv *);
  42
  43 struct smc_wr_rx_handler {
  44         struct hlist_node       list;   /* hash table collision resolution */
  45         void                    (*handler)(struct ib_wc *, void *);
  46         u8                      type;
  47 };
  48
  49 /* Only used by RDMA write WRs.
  50  * All other WRs (CDC/LLC) use smc_wr_tx_send handling WR_ID implicitly
  51  */
  52 static inline long smc_wr_tx_get_next_wr_id(struct smc_link *link)
  53 {
  54         return atomic_long_inc_return(&link->wr_tx_id);
  55 }
  56
  57 static inline void smc_wr_tx_set_wr_id(atomic_long_t *wr_tx_id, long val)
  58 {
  59         atomic_long_set(wr_tx_id, val);
  60 }
  61
  62 static inline bool smc_wr_tx_link_hold(struct smc_link *link)
  63 {
  64         if (!smc_link_sendable(link))
  65                 return false;
  66         atomic_inc(&link->wr_tx_refcnt);
  67         return true;
  68 }
  69
  70 static inline void smc_wr_tx_link_put(struct smc_link *link)
  71 {
  72         if (atomic_dec_and_test(&link->wr_tx_refcnt))
  73                 wake_up_all(&link->wr_tx_wait);
  74 }
  75
  76 static inline void smc_wr_wakeup_tx_wait(struct smc_link *lnk)
  77 {
  78         wake_up_all(&lnk->wr_tx_wait);
  79 }
  80
  81 static inline void smc_wr_wakeup_reg_wait(struct smc_link *lnk)
  82 {
  83         wake_up(&lnk->wr_reg_wait);
  84 }
  85
  86 /* post a new receive work request to fill a completed old work request entry */
  87 static inline int smc_wr_rx_post(struct smc_link *link)
  88 {
  89         int rc;
  90         u64 wr_id, temp_wr_id;
  91         u32 index;
  92
  93         wr_id = ++link->wr_rx_id; /* tasklet context, thus not atomic */
  94         temp_wr_id = wr_id;
  95         index = do_div(temp_wr_id, link->wr_rx_cnt);
  96         link->wr_rx_ibs[index].wr_id = wr_id;
  97         rc = ib_post_recv(link->roce_qp, &link->wr_rx_ibs[index], NULL);
  98         return rc;
  99 }
 100
 101 int smc_wr_create_link(struct smc_link *lnk);
 102 int smc_wr_alloc_link_mem(struct smc_link *lnk);
 103 int smc_wr_alloc_lgr_mem(struct smc_link_group *lgr);
 104 void smc_wr_free_link(struct smc_link *lnk);
 105 void smc_wr_free_link_mem(struct smc_link *lnk);
 106 void smc_wr_free_lgr_mem(struct smc_link_group *lgr);
 107 void smc_wr_remember_qp_attr(struct smc_link *lnk);
 108 void smc_wr_remove_dev(struct smc_ib_device *smcibdev);
 109 void smc_wr_add_dev(struct smc_ib_device *smcibdev);
 110
 111 int smc_wr_tx_get_free_slot(struct smc_link *link, smc_wr_tx_handler handler,
 112                             struct smc_wr_buf **wr_buf,
 113                             struct smc_rdma_wr **wrs,
 114                             struct smc_wr_tx_pend_priv **wr_pend_priv);
 115 int smc_wr_tx_get_v2_slot(struct smc_link *link,
 116                           smc_wr_tx_handler handler,
 117                           struct smc_wr_v2_buf **wr_buf,
 118                           struct smc_wr_tx_pend_priv **wr_pend_priv);
 119 int smc_wr_tx_put_slot(struct smc_link *link,
 120                        struct smc_wr_tx_pend_priv *wr_pend_priv);
 121 int smc_wr_tx_send(struct smc_link *link,
 122                    struct smc_wr_tx_pend_priv *wr_pend_priv);
 123 int smc_wr_tx_v2_send(struct smc_link *link,
 124                       struct smc_wr_tx_pend_priv *priv, int len);
 125 int smc_wr_tx_send_wait(struct smc_link *link, struct smc_wr_tx_pend_priv *priv,
 126                         unsigned long timeout);
 127 void smc_wr_tx_cq_handler(struct ib_cq *ib_cq, void *cq_context);
 128 void smc_wr_tx_wait_no_pending_sends(struct smc_link *link);
 129
 130 int smc_wr_rx_register_handler(struct smc_wr_rx_handler *handler);
 131 int smc_wr_rx_post_init(struct smc_link *link);
 132 void smc_wr_rx_cq_handler(struct ib_cq *ib_cq, void *cq_context);
 133 int smc_wr_reg_send(struct smc_link *link, struct ib_mr *mr);
 134
 135 #endif /* SMC_WR_H */