1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0 */
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * Shared Memory Communications over RDMA (SMC-R) and RoCE
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * Work Requests exploiting Infiniband API
6*4882a593Smuzhiyun *
7*4882a593Smuzhiyun * Copyright IBM Corp. 2016
8*4882a593Smuzhiyun *
9*4882a593Smuzhiyun * Author(s): Steffen Maier <maier@linux.vnet.ibm.com>
10*4882a593Smuzhiyun */
11*4882a593Smuzhiyun
12*4882a593Smuzhiyun #ifndef SMC_WR_H
13*4882a593Smuzhiyun #define SMC_WR_H
14*4882a593Smuzhiyun
15*4882a593Smuzhiyun #include <linux/atomic.h>
16*4882a593Smuzhiyun #include <rdma/ib_verbs.h>
17*4882a593Smuzhiyun #include <asm/div64.h>
18*4882a593Smuzhiyun
19*4882a593Smuzhiyun #include "smc.h"
20*4882a593Smuzhiyun #include "smc_core.h"
21*4882a593Smuzhiyun
22*4882a593Smuzhiyun #define SMC_WR_BUF_CNT 16 /* # of ctrl buffers per link */
23*4882a593Smuzhiyun
24*4882a593Smuzhiyun #define SMC_WR_TX_WAIT_FREE_SLOT_TIME (10 * HZ)
25*4882a593Smuzhiyun
26*4882a593Smuzhiyun #define SMC_WR_TX_SIZE 44 /* actual size of wr_send data (<=SMC_WR_BUF_SIZE) */
27*4882a593Smuzhiyun
28*4882a593Smuzhiyun #define SMC_WR_TX_PEND_PRIV_SIZE 32
29*4882a593Smuzhiyun
30*4882a593Smuzhiyun struct smc_wr_tx_pend_priv {
31*4882a593Smuzhiyun u8 priv[SMC_WR_TX_PEND_PRIV_SIZE];
32*4882a593Smuzhiyun };
33*4882a593Smuzhiyun
34*4882a593Smuzhiyun typedef void (*smc_wr_tx_handler)(struct smc_wr_tx_pend_priv *,
35*4882a593Smuzhiyun struct smc_link *,
36*4882a593Smuzhiyun enum ib_wc_status);
37*4882a593Smuzhiyun
38*4882a593Smuzhiyun typedef bool (*smc_wr_tx_filter)(struct smc_wr_tx_pend_priv *,
39*4882a593Smuzhiyun unsigned long);
40*4882a593Smuzhiyun
41*4882a593Smuzhiyun typedef void (*smc_wr_tx_dismisser)(struct smc_wr_tx_pend_priv *);
42*4882a593Smuzhiyun
43*4882a593Smuzhiyun struct smc_wr_rx_handler {
44*4882a593Smuzhiyun struct hlist_node list; /* hash table collision resolution */
45*4882a593Smuzhiyun void (*handler)(struct ib_wc *, void *);
46*4882a593Smuzhiyun u8 type;
47*4882a593Smuzhiyun };
48*4882a593Smuzhiyun
49*4882a593Smuzhiyun /* Only used by RDMA write WRs.
50*4882a593Smuzhiyun * All other WRs (CDC/LLC) use smc_wr_tx_send handling WR_ID implicitly
51*4882a593Smuzhiyun */
smc_wr_tx_get_next_wr_id(struct smc_link * link)52*4882a593Smuzhiyun static inline long smc_wr_tx_get_next_wr_id(struct smc_link *link)
53*4882a593Smuzhiyun {
54*4882a593Smuzhiyun return atomic_long_inc_return(&link->wr_tx_id);
55*4882a593Smuzhiyun }
56*4882a593Smuzhiyun
smc_wr_tx_set_wr_id(atomic_long_t * wr_tx_id,long val)57*4882a593Smuzhiyun static inline void smc_wr_tx_set_wr_id(atomic_long_t *wr_tx_id, long val)
58*4882a593Smuzhiyun {
59*4882a593Smuzhiyun atomic_long_set(wr_tx_id, val);
60*4882a593Smuzhiyun }
61*4882a593Smuzhiyun
smc_wr_tx_link_hold(struct smc_link * link)62*4882a593Smuzhiyun static inline bool smc_wr_tx_link_hold(struct smc_link *link)
63*4882a593Smuzhiyun {
64*4882a593Smuzhiyun if (!smc_link_sendable(link))
65*4882a593Smuzhiyun return false;
66*4882a593Smuzhiyun atomic_inc(&link->wr_tx_refcnt);
67*4882a593Smuzhiyun return true;
68*4882a593Smuzhiyun }
69*4882a593Smuzhiyun
smc_wr_tx_link_put(struct smc_link * link)70*4882a593Smuzhiyun static inline void smc_wr_tx_link_put(struct smc_link *link)
71*4882a593Smuzhiyun {
72*4882a593Smuzhiyun if (atomic_dec_and_test(&link->wr_tx_refcnt))
73*4882a593Smuzhiyun wake_up_all(&link->wr_tx_wait);
74*4882a593Smuzhiyun }
75*4882a593Smuzhiyun
smc_wr_wakeup_tx_wait(struct smc_link * lnk)76*4882a593Smuzhiyun static inline void smc_wr_wakeup_tx_wait(struct smc_link *lnk)
77*4882a593Smuzhiyun {
78*4882a593Smuzhiyun wake_up_all(&lnk->wr_tx_wait);
79*4882a593Smuzhiyun }
80*4882a593Smuzhiyun
smc_wr_wakeup_reg_wait(struct smc_link * lnk)81*4882a593Smuzhiyun static inline void smc_wr_wakeup_reg_wait(struct smc_link *lnk)
82*4882a593Smuzhiyun {
83*4882a593Smuzhiyun wake_up(&lnk->wr_reg_wait);
84*4882a593Smuzhiyun }
85*4882a593Smuzhiyun
86*4882a593Smuzhiyun /* post a new receive work request to fill a completed old work request entry */
smc_wr_rx_post(struct smc_link * link)87*4882a593Smuzhiyun static inline int smc_wr_rx_post(struct smc_link *link)
88*4882a593Smuzhiyun {
89*4882a593Smuzhiyun int rc;
90*4882a593Smuzhiyun u64 wr_id, temp_wr_id;
91*4882a593Smuzhiyun u32 index;
92*4882a593Smuzhiyun
93*4882a593Smuzhiyun wr_id = ++link->wr_rx_id; /* tasklet context, thus not atomic */
94*4882a593Smuzhiyun temp_wr_id = wr_id;
95*4882a593Smuzhiyun index = do_div(temp_wr_id, link->wr_rx_cnt);
96*4882a593Smuzhiyun link->wr_rx_ibs[index].wr_id = wr_id;
97*4882a593Smuzhiyun rc = ib_post_recv(link->roce_qp, &link->wr_rx_ibs[index], NULL);
98*4882a593Smuzhiyun return rc;
99*4882a593Smuzhiyun }
100*4882a593Smuzhiyun
101*4882a593Smuzhiyun int smc_wr_create_link(struct smc_link *lnk);
102*4882a593Smuzhiyun int smc_wr_alloc_link_mem(struct smc_link *lnk);
103*4882a593Smuzhiyun void smc_wr_free_link(struct smc_link *lnk);
104*4882a593Smuzhiyun void smc_wr_free_link_mem(struct smc_link *lnk);
105*4882a593Smuzhiyun void smc_wr_remember_qp_attr(struct smc_link *lnk);
106*4882a593Smuzhiyun void smc_wr_remove_dev(struct smc_ib_device *smcibdev);
107*4882a593Smuzhiyun void smc_wr_add_dev(struct smc_ib_device *smcibdev);
108*4882a593Smuzhiyun
109*4882a593Smuzhiyun int smc_wr_tx_get_free_slot(struct smc_link *link, smc_wr_tx_handler handler,
110*4882a593Smuzhiyun struct smc_wr_buf **wr_buf,
111*4882a593Smuzhiyun struct smc_rdma_wr **wrs,
112*4882a593Smuzhiyun struct smc_wr_tx_pend_priv **wr_pend_priv);
113*4882a593Smuzhiyun int smc_wr_tx_put_slot(struct smc_link *link,
114*4882a593Smuzhiyun struct smc_wr_tx_pend_priv *wr_pend_priv);
115*4882a593Smuzhiyun int smc_wr_tx_send(struct smc_link *link,
116*4882a593Smuzhiyun struct smc_wr_tx_pend_priv *wr_pend_priv);
117*4882a593Smuzhiyun int smc_wr_tx_send_wait(struct smc_link *link, struct smc_wr_tx_pend_priv *priv,
118*4882a593Smuzhiyun unsigned long timeout);
119*4882a593Smuzhiyun void smc_wr_tx_cq_handler(struct ib_cq *ib_cq, void *cq_context);
120*4882a593Smuzhiyun void smc_wr_tx_dismiss_slots(struct smc_link *lnk, u8 wr_rx_hdr_type,
121*4882a593Smuzhiyun smc_wr_tx_filter filter,
122*4882a593Smuzhiyun smc_wr_tx_dismisser dismisser,
123*4882a593Smuzhiyun unsigned long data);
124*4882a593Smuzhiyun void smc_wr_tx_wait_no_pending_sends(struct smc_link *link);
125*4882a593Smuzhiyun
126*4882a593Smuzhiyun int smc_wr_rx_register_handler(struct smc_wr_rx_handler *handler);
127*4882a593Smuzhiyun int smc_wr_rx_post_init(struct smc_link *link);
128*4882a593Smuzhiyun void smc_wr_rx_cq_handler(struct ib_cq *ib_cq, void *cq_context);
129*4882a593Smuzhiyun int smc_wr_reg_send(struct smc_link *link, struct ib_mr *mr);
130*4882a593Smuzhiyun
131*4882a593Smuzhiyun #endif /* SMC_WR_H */
132