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         percpu_ref_get(&link->wr_tx_refs);
  67         return true;
  68 }
  69
  70 static inline void smc_wr_tx_link_put(struct smc_link *link)
  71 {
  72         percpu_ref_put(&link->wr_tx_refs);
  73 }
  74
  75 static inline void smc_wr_drain_cq(struct smc_link *lnk)
  76 {
  77         wait_event(lnk->wr_rx_empty_wait, lnk->wr_rx_id_compl == lnk->wr_rx_id);
  78 }
  79
  80 static inline void smc_wr_wakeup_tx_wait(struct smc_link *lnk)
  81 {
  82         wake_up_all(&lnk->wr_tx_wait);
  83 }
  84
  85 static inline void smc_wr_wakeup_reg_wait(struct smc_link *lnk)
  86 {
  87         wake_up(&lnk->wr_reg_wait);
  88 }
  89
  90 /* post a new receive work request to fill a completed old work request entry */
  91 static inline int smc_wr_rx_post(struct smc_link *link)
  92 {
  93         int rc;
  94         u64 wr_id, temp_wr_id;
  95         u32 index;
  96
  97         wr_id = ++link->wr_rx_id; /* tasklet context, thus not atomic */
  98         temp_wr_id = wr_id;
  99         index = do_div(temp_wr_id, link->wr_rx_cnt);
 100         link->wr_rx_ibs[index].wr_id = wr_id;
 101         rc = ib_post_recv(link->roce_qp, &link->wr_rx_ibs[index], NULL);
 102         return rc;
 103 }
 104
 105 int smc_wr_create_link(struct smc_link *lnk);
 106 int smc_wr_alloc_link_mem(struct smc_link *lnk);
 107 int smc_wr_alloc_lgr_mem(struct smc_link_group *lgr);
 108 void smc_wr_free_link(struct smc_link *lnk);
 109 void smc_wr_free_link_mem(struct smc_link *lnk);
 110 void smc_wr_free_lgr_mem(struct smc_link_group *lgr);
 111 void smc_wr_remember_qp_attr(struct smc_link *lnk);
 112 void smc_wr_remove_dev(struct smc_ib_device *smcibdev);
 113 void smc_wr_add_dev(struct smc_ib_device *smcibdev);
 114
 115 int smc_wr_tx_get_free_slot(struct smc_link *link, smc_wr_tx_handler handler,
 116                             struct smc_wr_buf **wr_buf,
 117                             struct smc_rdma_wr **wrs,
 118                             struct smc_wr_tx_pend_priv **wr_pend_priv);
 119 int smc_wr_tx_get_v2_slot(struct smc_link *link,
 120                           smc_wr_tx_handler handler,
 121                           struct smc_wr_v2_buf **wr_buf,
 122                           struct smc_wr_tx_pend_priv **wr_pend_priv);
 123 int smc_wr_tx_put_slot(struct smc_link *link,
 124                        struct smc_wr_tx_pend_priv *wr_pend_priv);
 125 int smc_wr_tx_send(struct smc_link *link,
 126                    struct smc_wr_tx_pend_priv *wr_pend_priv);
 127 int smc_wr_tx_v2_send(struct smc_link *link,
 128                       struct smc_wr_tx_pend_priv *priv, int len);
 129 int smc_wr_tx_send_wait(struct smc_link *link, struct smc_wr_tx_pend_priv *priv,
 130                         unsigned long timeout);
 131 void smc_wr_tx_cq_handler(struct ib_cq *ib_cq, void *cq_context);
 132 void smc_wr_tx_wait_no_pending_sends(struct smc_link *link);
 133
 134 int smc_wr_rx_register_handler(struct smc_wr_rx_handler *handler);
 135 int smc_wr_rx_post_init(struct smc_link *link);
 136 void smc_wr_rx_cq_handler(struct ib_cq *ib_cq, void *cq_context);
 137 int smc_wr_reg_send(struct smc_link *link, struct ib_mr *mr);
 138
 139 #endif /* SMC_WR_H */