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_MAX_CQE 32768    /* max. # of completion queue elements */
  23 #define SMC_WR_BUF_CNT 16       /* # of ctrl buffers per link */
  24
  25 #define SMC_WR_TX_WAIT_FREE_SLOT_TIME   (10 * HZ)
  26 #define SMC_WR_TX_WAIT_PENDING_TIME     (5 * HZ)
  27
  28 #define SMC_WR_TX_SIZE 44 /* actual size of wr_send data (<=SMC_WR_BUF_SIZE) */
  29
  30 #define SMC_WR_TX_PEND_PRIV_SIZE 32
  31
  32 struct smc_wr_tx_pend_priv {
  33         u8                      priv[SMC_WR_TX_PEND_PRIV_SIZE];
  34 };
  35
  36 typedef void (*smc_wr_tx_handler)(struct smc_wr_tx_pend_priv *,
  37                                   struct smc_link *,
  38                                   enum ib_wc_status);
  39
  40 typedef bool (*smc_wr_tx_filter)(struct smc_wr_tx_pend_priv *,
  41                                  unsigned long);
  42
  43 typedef void (*smc_wr_tx_dismisser)(struct smc_wr_tx_pend_priv *);
  44
  45 struct smc_wr_rx_handler {
  46         struct hlist_node       list;   /* hash table collision resolution */
  47         void                    (*handler)(struct ib_wc *, void *);
  48         u8                      type;
  49 };
  50
  51 /* Only used by RDMA write WRs.
  52  * All other WRs (CDC/LLC) use smc_wr_tx_send handling WR_ID implicitly
  53  */
  54 static inline long smc_wr_tx_get_next_wr_id(struct smc_link *link)
  55 {
  56         return atomic_long_inc_return(&link->wr_tx_id);
  57 }
  58
  59 static inline void smc_wr_tx_set_wr_id(atomic_long_t *wr_tx_id, long val)
  60 {
  61         atomic_long_set(wr_tx_id, val);
  62 }
  63
  64 /* post a new receive work request to fill a completed old work request entry */
  65 static inline int smc_wr_rx_post(struct smc_link *link)
  66 {
  67         struct ib_recv_wr *bad_recv_wr = NULL;
  68         int rc;
  69         u64 wr_id, temp_wr_id;
  70         u32 index;
  71
  72         wr_id = ++link->wr_rx_id; /* tasklet context, thus not atomic */
  73         temp_wr_id = wr_id;
  74         index = do_div(temp_wr_id, link->wr_rx_cnt);
  75         link->wr_rx_ibs[index].wr_id = wr_id;
  76         rc = ib_post_recv(link->roce_qp, &link->wr_rx_ibs[index], &bad_recv_wr);
  77         return rc;
  78 }
  79
  80 int smc_wr_create_link(struct smc_link *lnk);
  81 int smc_wr_alloc_link_mem(struct smc_link *lnk);
  82 void smc_wr_free_link(struct smc_link *lnk);
  83 void smc_wr_free_link_mem(struct smc_link *lnk);
  84 void smc_wr_remember_qp_attr(struct smc_link *lnk);
  85 void smc_wr_remove_dev(struct smc_ib_device *smcibdev);
  86 void smc_wr_add_dev(struct smc_ib_device *smcibdev);
  87
  88 int smc_wr_tx_get_free_slot(struct smc_link *link, smc_wr_tx_handler handler,
  89                             struct smc_wr_buf **wr_buf,
  90                             struct smc_wr_tx_pend_priv **wr_pend_priv);
  91 int smc_wr_tx_put_slot(struct smc_link *link,
  92                        struct smc_wr_tx_pend_priv *wr_pend_priv);
  93 int smc_wr_tx_send(struct smc_link *link,
  94                    struct smc_wr_tx_pend_priv *wr_pend_priv);
  95 void smc_wr_tx_cq_handler(struct ib_cq *ib_cq, void *cq_context);
  96 void smc_wr_tx_dismiss_slots(struct smc_link *lnk, u8 wr_rx_hdr_type,
  97                              smc_wr_tx_filter filter,
  98                              smc_wr_tx_dismisser dismisser,
  99                              unsigned long data);
 100
 101 int smc_wr_rx_register_handler(struct smc_wr_rx_handler *handler);
 102 int smc_wr_rx_post_init(struct smc_link *link);
 103 void smc_wr_rx_cq_handler(struct ib_cq *ib_cq, void *cq_context);
 104 int smc_wr_reg_send(struct smc_link *link, struct ib_mr *mr);
 105
 106 #endif /* SMC_WR_H */