1 /* SPDX-License-Identifier: GPL-2.0 */
3 * Shared Memory Communications over RDMA (SMC-R) and RoCE
5 * Definitions for SMC Connections, Link Groups and Links
7 * Copyright IBM Corp. 2016
9 * Author(s): Ursula Braun <ubraun@linux.vnet.ibm.com>
15 #include <linux/atomic.h>
16 #include <rdma/ib_verbs.h>
21 #define SMC_RMBS_PER_LGR_MAX 255 /* max. # of RMBs per link group */
23 struct smc_lgr_list { /* list of link group definition */
24 struct list_head list;
25 spinlock_t lock; /* protects list of link groups */
28 extern struct smc_lgr_list smc_lgr_list; /* list of link groups */
30 enum smc_lgr_role { /* possible roles of a link group */
31 SMC_CLNT, /* client */
35 #define SMC_WR_BUF_SIZE 48 /* size of work request buffer */
38 u8 raw[SMC_WR_BUF_SIZE];
41 #define SMC_WR_REG_MR_WAIT_TIME (5 * HZ)/* wait time for ib_wr_reg_mr result */
43 enum smc_wr_reg_state {
44 POSTED, /* ib_wr_reg_mr request posted */
45 CONFIRMED, /* ib_wr_reg_mr response: successful */
46 FAILED /* ib_wr_reg_mr response: failure */
50 struct smc_ib_device *smcibdev; /* ib-device */
51 u8 ibport; /* port - values 1 | 2 */
52 struct ib_pd *roce_pd; /* IB protection domain,
53 * unique for every RoCE QP
55 struct ib_qp *roce_qp; /* IB queue pair */
56 struct ib_qp_attr qp_attr; /* IB queue pair attributes */
58 struct smc_wr_buf *wr_tx_bufs; /* WR send payload buffers */
59 struct ib_send_wr *wr_tx_ibs; /* WR send meta data */
60 struct ib_sge *wr_tx_sges; /* WR send gather meta data */
61 struct smc_wr_tx_pend *wr_tx_pends; /* WR send waiting for CQE */
62 /* above four vectors have wr_tx_cnt elements and use the same index */
63 dma_addr_t wr_tx_dma_addr; /* DMA address of wr_tx_bufs */
64 atomic_long_t wr_tx_id; /* seq # of last sent WR */
65 unsigned long *wr_tx_mask; /* bit mask of used indexes */
66 u32 wr_tx_cnt; /* number of WR send buffers */
67 wait_queue_head_t wr_tx_wait; /* wait for free WR send buf */
69 struct smc_wr_buf *wr_rx_bufs; /* WR recv payload buffers */
70 struct ib_recv_wr *wr_rx_ibs; /* WR recv meta data */
71 struct ib_sge *wr_rx_sges; /* WR recv scatter meta data */
72 /* above three vectors have wr_rx_cnt elements and use the same index */
73 dma_addr_t wr_rx_dma_addr; /* DMA address of wr_rx_bufs */
74 u64 wr_rx_id; /* seq # of last recv WR */
75 u32 wr_rx_cnt; /* number of WR recv buffers */
77 struct ib_reg_wr wr_reg; /* WR register memory region */
78 wait_queue_head_t wr_reg_wait; /* wait for wr_reg result */
79 enum smc_wr_reg_state wr_reg_state; /* state of wr_reg request */
81 union ib_gid gid; /* gid matching used vlan id */
82 u32 peer_qpn; /* QP number of peer */
83 enum ib_mtu path_mtu; /* used mtu */
84 enum ib_mtu peer_mtu; /* mtu size of peer */
85 u32 psn_initial; /* QP tx initial packet seqno */
86 u32 peer_psn; /* QP rx initial packet seqno */
87 u8 peer_mac[ETH_ALEN]; /* = gid[8:10||13:15] */
88 u8 peer_gid[sizeof(union ib_gid)]; /* gid of peer*/
89 u8 link_id; /* unique # within link group */
90 struct completion llc_confirm; /* wait for rx of conf link */
91 struct completion llc_confirm_resp; /* wait 4 rx of cnf lnk rsp */
92 int llc_confirm_rc; /* rc from confirm link msg */
93 int llc_confirm_resp_rc; /* rc from conf_resp msg */
96 /* For now we just allow one parallel link per link group. The SMC protocol
97 * allows more (up to 8).
99 #define SMC_LINKS_PER_LGR_MAX 1
100 #define SMC_SINGLE_LINK 0
102 #define SMC_FIRST_CONTACT 1 /* first contact to a peer */
103 #define SMC_REUSE_CONTACT 0 /* follow-on contact to a peer*/
105 /* tx/rx buffer list element for sndbufs list and rmbs list of a lgr */
106 struct smc_buf_desc {
107 struct list_head list;
108 void *cpu_addr; /* virtual address of buffer */
109 struct sg_table sgt[SMC_LINKS_PER_LGR_MAX];/* virtual buffer */
110 struct ib_mr *mr_rx[SMC_LINKS_PER_LGR_MAX];
111 /* for rmb only: memory region
112 * incl. rkey provided to peer
114 u32 order; /* allocation order */
115 u32 used; /* currently used / unused */
116 bool reused; /* new created / reused */
119 struct smc_rtoken { /* address/key of remote RMB */
124 #define SMC_LGR_ID_SIZE 4
126 struct smc_link_group {
127 struct list_head list;
128 enum smc_lgr_role role; /* client or server */
129 struct smc_link lnk[SMC_LINKS_PER_LGR_MAX]; /* smc link */
130 char peer_systemid[SMC_SYSTEMID_LEN];
131 /* unique system_id of peer */
132 struct rb_root conns_all; /* connection tree */
133 rwlock_t conns_lock; /* protects conns_all */
134 unsigned int conns_num; /* current # of connections */
135 unsigned short vlan_id; /* vlan id of link group */
137 struct list_head sndbufs[SMC_RMBE_SIZES];/* tx buffers */
138 rwlock_t sndbufs_lock; /* protects tx buffers */
139 struct list_head rmbs[SMC_RMBE_SIZES]; /* rx buffers */
140 rwlock_t rmbs_lock; /* protects rx buffers */
141 struct smc_rtoken rtokens[SMC_RMBS_PER_LGR_MAX]
142 [SMC_LINKS_PER_LGR_MAX];
143 /* remote addr/key pairs */
144 unsigned long rtokens_used_mask[BITS_TO_LONGS(
145 SMC_RMBS_PER_LGR_MAX)];
146 /* used rtoken elements */
148 u8 id[SMC_LGR_ID_SIZE]; /* unique lgr id */
149 struct delayed_work free_work; /* delayed freeing of an lgr */
150 bool sync_err; /* lgr no longer fits to peer */
153 /* Find the connection associated with the given alert token in the link group.
154 * To use rbtrees we have to implement our own search core.
155 * Requires @conns_lock
156 * @token alert token to search for
157 * @lgr link group to search in
158 * Returns connection associated with token if found, NULL otherwise.
160 static inline struct smc_connection *smc_lgr_find_conn(
161 u32 token, struct smc_link_group *lgr)
163 struct smc_connection *res = NULL;
164 struct rb_node *node;
166 node = lgr->conns_all.rb_node;
168 struct smc_connection *cur = rb_entry(node,
169 struct smc_connection, alert_node);
171 if (cur->alert_token_local > token) {
172 node = node->rb_left;
174 if (cur->alert_token_local < token) {
175 node = node->rb_right;
187 struct smc_clc_msg_accept_confirm;
189 void smc_lgr_free(struct smc_link_group *lgr);
190 void smc_lgr_terminate(struct smc_link_group *lgr);
191 int smc_buf_create(struct smc_sock *smc);
192 int smc_rmb_rtoken_handling(struct smc_connection *conn,
193 struct smc_clc_msg_accept_confirm *clc);
194 int smc_rtoken_add(struct smc_link_group *lgr, __be64 nw_vaddr, __be32 nw_rkey);
195 int smc_rtoken_delete(struct smc_link_group *lgr, __be32 nw_rkey);
196 void smc_sndbuf_sync_sg_for_cpu(struct smc_connection *conn);
197 void smc_sndbuf_sync_sg_for_device(struct smc_connection *conn);
198 void smc_rmb_sync_sg_for_cpu(struct smc_connection *conn);
199 void smc_rmb_sync_sg_for_device(struct smc_connection *conn);