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(v: &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(v: wr_tx_id, i: val);
58}
59
60static inline bool smc_wr_tx_link_hold(struct smc_link *link)
61{
62 if (!smc_link_sendable(lnk: link))
63 return false;
64 percpu_ref_get(ref: &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(ref: &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(qp: link->roce_qp, recv_wr: &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 */
138

source code of linux/net/smc/smc_wr.h