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 */
smc_wr_tx_get_next_wr_id(struct smc_link * link)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
smc_wr_tx_set_wr_id(atomic_long_t * wr_tx_id,long val)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
smc_wr_tx_link_hold(struct smc_link * link)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
smc_wr_tx_link_put(struct smc_link * link)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
smc_wr_wakeup_tx_wait(struct smc_link * lnk)76 static inline void smc_wr_wakeup_tx_wait(struct smc_link *lnk)
77 {
78 wake_up_all(&lnk->wr_tx_wait);
79 }
80
smc_wr_wakeup_reg_wait(struct smc_link * lnk)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 */
smc_wr_rx_post(struct smc_link * link)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 void smc_wr_free_link(struct smc_link *lnk);
104 void smc_wr_free_link_mem(struct smc_link *lnk);
105 void smc_wr_remember_qp_attr(struct smc_link *lnk);
106 void smc_wr_remove_dev(struct smc_ib_device *smcibdev);
107 void smc_wr_add_dev(struct smc_ib_device *smcibdev);
108
109 int smc_wr_tx_get_free_slot(struct smc_link *link, smc_wr_tx_handler handler,
110 struct smc_wr_buf **wr_buf,
111 struct smc_rdma_wr **wrs,
112 struct smc_wr_tx_pend_priv **wr_pend_priv);
113 int smc_wr_tx_put_slot(struct smc_link *link,
114 struct smc_wr_tx_pend_priv *wr_pend_priv);
115 int smc_wr_tx_send(struct smc_link *link,
116 struct smc_wr_tx_pend_priv *wr_pend_priv);
117 int smc_wr_tx_send_wait(struct smc_link *link, struct smc_wr_tx_pend_priv *priv,
118 unsigned long timeout);
119 void smc_wr_tx_cq_handler(struct ib_cq *ib_cq, void *cq_context);
120 void smc_wr_tx_dismiss_slots(struct smc_link *lnk, u8 wr_rx_hdr_type,
121 smc_wr_tx_filter filter,
122 smc_wr_tx_dismisser dismisser,
123 unsigned long data);
124 void smc_wr_tx_wait_no_pending_sends(struct smc_link *link);
125
126 int smc_wr_rx_register_handler(struct smc_wr_rx_handler *handler);
127 int smc_wr_rx_post_init(struct smc_link *link);
128 void smc_wr_rx_cq_handler(struct ib_cq *ib_cq, void *cq_context);
129 int smc_wr_reg_send(struct smc_link *link, struct ib_mr *mr);
130
131 #endif /* SMC_WR_H */
132