smc.h

  1/* SPDX-License-Identifier: GPL-2.0 */
  2/*
  3 *  Shared Memory Communications over RDMA (SMC-R) and RoCE
  4 *
  5 *  Definitions for the SMC module (socket related)
  6 *
  7 *  Copyright IBM Corp. 2016
  8 *
  9 *  Author(s):  Ursula Braun <ubraun@linux.vnet.ibm.com>
 10 */
 11#ifndef _SMC_H
 12#define _SMC_H
 13
 14#include <linux/device.h>
 15#include <linux/spinlock.h>
 16#include <linux/types.h>
 17#include <linux/wait.h>
 18#include <linux/dibs.h>
 19
 20struct tcp_sock;
 21struct inet_request_sock;
 22struct sock;
 23
 24#define SMC_MAX_PNETID_LEN	16	/* Max. length of PNET id */
 25
 26struct smc_hashinfo {
 27	rwlock_t lock;
 28	struct hlist_head ht;
 29};
 30
 31/* SMCD/ISM device driver interface */
 32#define ISM_RESERVED_VLANID	0x1FFF
 33
 34struct smcd_gid {
 35	u64	gid;
 36	u64	gid_ext;
 37};
 38
 39struct smcd_dev {
 40	struct dibs_dev *dibs;
 41	struct list_head list;
 42	spinlock_t lock;
 43	struct smc_connection **conn;
 44	struct list_head vlan;
 45	struct workqueue_struct *event_wq;
 46	u8 pnetid[SMC_MAX_PNETID_LEN];
 47	bool pnetid_by_user;
 48	struct list_head lgr_list;
 49	spinlock_t lgr_lock;
 50	atomic_t lgr_cnt;
 51	wait_queue_head_t lgrs_deleted;
 52	u8 going_away : 1;
 53};
 54
 55#define SMC_HS_CTRL_NAME_MAX 16
 56
 57enum {
 58	/* ops can be inherit from init_net */
 59	SMC_HS_CTRL_FLAG_INHERITABLE = 0x1,
 60
 61	SMC_HS_CTRL_ALL_FLAGS = SMC_HS_CTRL_FLAG_INHERITABLE,
 62};
 63
 64struct smc_hs_ctrl {
 65	/* private */
 66
 67	struct list_head list;
 68	struct module *owner;
 69
 70	/* public */
 71
 72	/* unique name */
 73	char name[SMC_HS_CTRL_NAME_MAX];
 74	int flags;
 75
 76	/* Invoked before computing SMC option for SYN packets.
 77	 * We can control whether to set SMC options by returning various value.
 78	 * Return 0 to disable SMC, or return any other value to enable it.
 79	 */
 80	int (*syn_option)(struct tcp_sock *tp);
 81
 82	/* Invoked before Set up SMC options for SYN-ACK packets
 83	 * We can control whether to respond SMC options by returning various
 84	 * value. Return 0 to disable SMC, or return any other value to enable
 85	 * it.
 86	 */
 87	int (*synack_option)(const struct tcp_sock *tp,
 88			     struct inet_request_sock *ireq);
 89};
 90
 91#if IS_ENABLED(CONFIG_SMC_HS_CTRL_BPF)
 92#define smc_call_hsbpf(init_val, tp, func, ...) ({				\
 93	typeof(init_val) __ret = (init_val);					\
 94	struct smc_hs_ctrl *ctrl;						\
 95	rcu_read_lock();							\
 96	ctrl = rcu_dereference(sock_net((struct sock *)(tp))->smc.hs_ctrl);	\
 97	if (ctrl && ctrl->func)							\
 98		__ret = ctrl->func(tp, ##__VA_ARGS__);				\
 99	rcu_read_unlock();							\
100	__ret;									\
101})
102#else
103#define smc_call_hsbpf(init_val, tp, ...)  ({ (void)(tp); (init_val); })
104#endif /* CONFIG_SMC_HS_CTRL_BPF */
105
106#endif	/* _SMC_H */