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_TX_WAIT_FREE_SLOT_TIME	(10 * HZ)
 23
 24#define SMC_WR_TX_SIZE 44 /* actual size of wr_send data (<=SMC_WR_BUF_SIZE) */
 25
 26#define SMC_WR_TX_PEND_PRIV_SIZE 32
 27
 28struct smc_wr_tx_pend_priv {
 29	u8			priv[SMC_WR_TX_PEND_PRIV_SIZE];
 30};
 31
 32typedef void (*smc_wr_tx_handler)(struct smc_wr_tx_pend_priv *,
 33				  struct smc_link *,
 34				  enum ib_wc_status);
 35
 36typedef bool (*smc_wr_tx_filter)(struct smc_wr_tx_pend_priv *,
 37				 unsigned long);
 38
 39typedef void (*smc_wr_tx_dismisser)(struct smc_wr_tx_pend_priv *);
 40
 41struct smc_wr_rx_handler {
 42	struct hlist_node	list;	/* hash table collision resolution */
 43	void			(*handler)(struct ib_wc *, void *);
 44	u8			type;
 45};
 46
 47/* Only used by RDMA write WRs.
 48 * All other WRs (CDC/LLC) use smc_wr_tx_send handling WR_ID implicitly
 49 */
 50static inline long smc_wr_tx_get_next_wr_id(struct smc_link *link)
 51{
 52	return atomic_long_inc_return(&link->wr_tx_id);
 53}
 54
 55static inline void smc_wr_tx_set_wr_id(atomic_long_t *wr_tx_id, long val)
 56{
 57	atomic_long_set(wr_tx_id, val);
 58}
 59
 60static inline bool smc_wr_tx_link_hold(struct smc_link *link)
 61{
 62	if (!smc_link_sendable(link))
 63		return false;
 64	percpu_ref_get(&link->wr_tx_refs);
 65	return true;
 66}
 67
 68static inline void smc_wr_tx_link_put(struct smc_link *link)
 69{
 70	percpu_ref_put(&link->wr_tx_refs);
 71}
 72
 73static inline void smc_wr_drain_cq(struct smc_link *lnk)
 74{
 75	wait_event(lnk->wr_rx_empty_wait, lnk->wr_rx_id_compl == lnk->wr_rx_id);
 76}
 77
 78static inline void smc_wr_wakeup_tx_wait(struct smc_link *lnk)
 79{
 80	wake_up_all(&lnk->wr_tx_wait);
 81}
 82
 83static inline void smc_wr_wakeup_reg_wait(struct smc_link *lnk)
 84{
 85	wake_up(&lnk->wr_reg_wait);
 86}
 87
 88/* post a new receive work request to fill a completed old work request entry */
 89static inline int smc_wr_rx_post(struct smc_link *link)
 90{
 91	int rc;
 92	u64 wr_id, temp_wr_id;
 93	u32 index;
 94
 95	wr_id = ++link->wr_rx_id; /* tasklet context, thus not atomic */
 96	temp_wr_id = wr_id;
 97	index = do_div(temp_wr_id, link->wr_rx_cnt);
 98	link->wr_rx_ibs[index].wr_id = wr_id;
 99	rc = ib_post_recv(link->roce_qp, &link->wr_rx_ibs[index], NULL);
100	return rc;
101}
102
103int smc_wr_create_link(struct smc_link *lnk);
104int smc_wr_alloc_link_mem(struct smc_link *lnk);
105int smc_wr_alloc_lgr_mem(struct smc_link_group *lgr);
106void smc_wr_free_link(struct smc_link *lnk);
107void smc_wr_free_link_mem(struct smc_link *lnk);
108void smc_wr_free_lgr_mem(struct smc_link_group *lgr);
109void smc_wr_remember_qp_attr(struct smc_link *lnk);
110void smc_wr_remove_dev(struct smc_ib_device *smcibdev);
111void smc_wr_add_dev(struct smc_ib_device *smcibdev);
112
113int smc_wr_tx_get_free_slot(struct smc_link *link, smc_wr_tx_handler handler,
114			    struct smc_wr_buf **wr_buf,
115			    struct smc_rdma_wr **wrs,
116			    struct smc_wr_tx_pend_priv **wr_pend_priv);
117int smc_wr_tx_get_v2_slot(struct smc_link *link,
118			  smc_wr_tx_handler handler,
119			  struct smc_wr_v2_buf **wr_buf,
120			  struct smc_wr_tx_pend_priv **wr_pend_priv);
121int smc_wr_tx_put_slot(struct smc_link *link,
122		       struct smc_wr_tx_pend_priv *wr_pend_priv);
123int smc_wr_tx_send(struct smc_link *link,
124		   struct smc_wr_tx_pend_priv *wr_pend_priv);
125int smc_wr_tx_v2_send(struct smc_link *link,
126		      struct smc_wr_tx_pend_priv *priv, int len);
127int smc_wr_tx_send_wait(struct smc_link *link, struct smc_wr_tx_pend_priv *priv,
128			unsigned long timeout);
129void smc_wr_tx_cq_handler(struct ib_cq *ib_cq, void *cq_context);
130void smc_wr_tx_wait_no_pending_sends(struct smc_link *link);
131
132int smc_wr_rx_register_handler(struct smc_wr_rx_handler *handler);
133int smc_wr_rx_post_init(struct smc_link *link);
134void smc_wr_rx_cq_handler(struct ib_cq *ib_cq, void *cq_context);
135int smc_wr_reg_send(struct smc_link *link, struct ib_mr *mr);
136
137#endif /* SMC_WR_H */