https://github.com/torvalds/linux
Tip revision: 30a0b95b1335e12efef89dd78518ed3e4a71a763 authored by Linus Torvalds on 30 October 2022, 22:19:28 UTC
Linux 6.1-rc3
Linux 6.1-rc3
Tip revision: 30a0b95
smc.h
/* SPDX-License-Identifier: GPL-2.0 */
/*
* Shared Memory Communications over RDMA (SMC-R) and RoCE
*
* Definitions for the SMC module (socket related)
*
* Copyright IBM Corp. 2016
*
* Author(s): Ursula Braun <ubraun@linux.vnet.ibm.com>
*/
#ifndef __SMC_H
#define __SMC_H
#include <linux/socket.h>
#include <linux/types.h>
#include <linux/compiler.h> /* __aligned */
#include <net/genetlink.h>
#include <net/sock.h>
#include "smc_ib.h"
#define SMC_V1 1 /* SMC version V1 */
#define SMC_V2 2 /* SMC version V2 */
#define SMC_RELEASE 0
#define SMCPROTO_SMC 0 /* SMC protocol, IPv4 */
#define SMCPROTO_SMC6 1 /* SMC protocol, IPv6 */
#define SMC_MAX_ISM_DEVS 8 /* max # of proposed non-native ISM
* devices
*/
#define SMC_AUTOCORKING_DEFAULT_SIZE 0x10000 /* 64K by default */
extern struct proto smc_proto;
extern struct proto smc_proto6;
#ifdef ATOMIC64_INIT
#define KERNEL_HAS_ATOMIC64
#endif
enum smc_state { /* possible states of an SMC socket */
SMC_ACTIVE = 1,
SMC_INIT = 2,
SMC_CLOSED = 7,
SMC_LISTEN = 10,
/* normal close */
SMC_PEERCLOSEWAIT1 = 20,
SMC_PEERCLOSEWAIT2 = 21,
SMC_APPFINCLOSEWAIT = 24,
SMC_APPCLOSEWAIT1 = 22,
SMC_APPCLOSEWAIT2 = 23,
SMC_PEERFINCLOSEWAIT = 25,
/* abnormal close */
SMC_PEERABORTWAIT = 26,
SMC_PROCESSABORT = 27,
};
struct smc_link_group;
struct smc_wr_rx_hdr { /* common prefix part of LLC and CDC to demultiplex */
union {
u8 type;
#if defined(__BIG_ENDIAN_BITFIELD)
struct {
u8 llc_version:4,
llc_type:4;
};
#elif defined(__LITTLE_ENDIAN_BITFIELD)
struct {
u8 llc_type:4,
llc_version:4;
};
#endif
};
} __aligned(1);
struct smc_cdc_conn_state_flags {
#if defined(__BIG_ENDIAN_BITFIELD)
u8 peer_done_writing : 1; /* Sending done indicator */
u8 peer_conn_closed : 1; /* Peer connection closed indicator */
u8 peer_conn_abort : 1; /* Abnormal close indicator */
u8 reserved : 5;
#elif defined(__LITTLE_ENDIAN_BITFIELD)
u8 reserved : 5;
u8 peer_conn_abort : 1;
u8 peer_conn_closed : 1;
u8 peer_done_writing : 1;
#endif
};
struct smc_cdc_producer_flags {
#if defined(__BIG_ENDIAN_BITFIELD)
u8 write_blocked : 1; /* Writing Blocked, no rx buf space */
u8 urg_data_pending : 1; /* Urgent Data Pending */
u8 urg_data_present : 1; /* Urgent Data Present */
u8 cons_curs_upd_req : 1; /* cursor update requested */
u8 failover_validation : 1;/* message replay due to failover */
u8 reserved : 3;
#elif defined(__LITTLE_ENDIAN_BITFIELD)
u8 reserved : 3;
u8 failover_validation : 1;
u8 cons_curs_upd_req : 1;
u8 urg_data_present : 1;
u8 urg_data_pending : 1;
u8 write_blocked : 1;
#endif
};
/* in host byte order */
union smc_host_cursor { /* SMC cursor - an offset in an RMBE */
struct {
u16 reserved;
u16 wrap; /* window wrap sequence number */
u32 count; /* cursor (= offset) part */
};
#ifdef KERNEL_HAS_ATOMIC64
atomic64_t acurs; /* for atomic processing */
#else
u64 acurs; /* for atomic processing */
#endif
} __aligned(8);
/* in host byte order, except for flag bitfields in network byte order */
struct smc_host_cdc_msg { /* Connection Data Control message */
struct smc_wr_rx_hdr common; /* .type = 0xFE */
u8 len; /* length = 44 */
u16 seqno; /* connection seq # */
u32 token; /* alert_token */
union smc_host_cursor prod; /* producer cursor */
union smc_host_cursor cons; /* consumer cursor,
* piggy backed "ack"
*/
struct smc_cdc_producer_flags prod_flags; /* conn. tx/rx status */
struct smc_cdc_conn_state_flags conn_state_flags; /* peer conn. status*/
u8 reserved[18];
} __aligned(8);
enum smc_urg_state {
SMC_URG_VALID = 1, /* data present */
SMC_URG_NOTYET = 2, /* data pending */
SMC_URG_READ = 3, /* data was already read */
};
struct smc_mark_woken {
bool woken;
void *key;
wait_queue_entry_t wait_entry;
};
struct smc_connection {
struct rb_node alert_node;
struct smc_link_group *lgr; /* link group of connection */
struct smc_link *lnk; /* assigned SMC-R link */
u32 alert_token_local; /* unique conn. id */
u8 peer_rmbe_idx; /* from tcp handshake */
int peer_rmbe_size; /* size of peer rx buffer */
atomic_t peer_rmbe_space;/* remaining free bytes in peer
* rmbe
*/
int rtoken_idx; /* idx to peer RMB rkey/addr */
struct smc_buf_desc *sndbuf_desc; /* send buffer descriptor */
struct smc_buf_desc *rmb_desc; /* RMBE descriptor */
int rmbe_size_short;/* compressed notation */
int rmbe_update_limit;
/* lower limit for consumer
* cursor update
*/
struct smc_host_cdc_msg local_tx_ctrl; /* host byte order staging
* buffer for CDC msg send
* .prod cf. TCP snd_nxt
* .cons cf. TCP sends ack
*/
union smc_host_cursor local_tx_ctrl_fin;
/* prod crsr - confirmed by peer
*/
union smc_host_cursor tx_curs_prep; /* tx - prepared data
* snd_max..wmem_alloc
*/
union smc_host_cursor tx_curs_sent; /* tx - sent data
* snd_nxt ?
*/
union smc_host_cursor tx_curs_fin; /* tx - confirmed by peer
* snd-wnd-begin ?
*/
atomic_t sndbuf_space; /* remaining space in sndbuf */
u16 tx_cdc_seq; /* sequence # for CDC send */
u16 tx_cdc_seq_fin; /* sequence # - tx completed */
spinlock_t send_lock; /* protect wr_sends */
atomic_t cdc_pend_tx_wr; /* number of pending tx CDC wqe
* - inc when post wqe,
* - dec on polled tx cqe
*/
wait_queue_head_t cdc_pend_tx_wq; /* wakeup on no cdc_pend_tx_wr*/
atomic_t tx_pushing; /* nr_threads trying tx push */
struct delayed_work tx_work; /* retry of smc_cdc_msg_send */
u32 tx_off; /* base offset in peer rmb */
struct smc_host_cdc_msg local_rx_ctrl; /* filled during event_handl.
* .prod cf. TCP rcv_nxt
* .cons cf. TCP snd_una
*/
union smc_host_cursor rx_curs_confirmed; /* confirmed to peer
* source of snd_una ?
*/
union smc_host_cursor urg_curs; /* points at urgent byte */
enum smc_urg_state urg_state;
bool urg_tx_pend; /* urgent data staged */
bool urg_rx_skip_pend;
/* indicate urgent oob data
* read, but previous regular
* data still pending
*/
char urg_rx_byte; /* urgent byte */
bool tx_in_release_sock;
/* flush pending tx data in
* sock release_cb()
*/
atomic_t bytes_to_rcv; /* arrived data,
* not yet received
*/
atomic_t splice_pending; /* number of spliced bytes
* pending processing
*/
#ifndef KERNEL_HAS_ATOMIC64
spinlock_t acurs_lock; /* protect cursors */
#endif
struct work_struct close_work; /* peer sent some closing */
struct work_struct abort_work; /* abort the connection */
struct tasklet_struct rx_tsklet; /* Receiver tasklet for SMC-D */
u8 rx_off; /* receive offset:
* 0 for SMC-R, 32 for SMC-D
*/
u64 peer_token; /* SMC-D token of peer */
u8 killed : 1; /* abnormal termination */
u8 freed : 1; /* normal termiation */
u8 out_of_sync : 1; /* out of sync with peer */
};
struct smc_sock { /* smc sock container */
struct sock sk;
struct socket *clcsock; /* internal tcp socket */
void (*clcsk_state_change)(struct sock *sk);
/* original stat_change fct. */
void (*clcsk_data_ready)(struct sock *sk);
/* original data_ready fct. */
void (*clcsk_write_space)(struct sock *sk);
/* original write_space fct. */
void (*clcsk_error_report)(struct sock *sk);
/* original error_report fct. */
struct smc_connection conn; /* smc connection */
struct smc_sock *listen_smc; /* listen parent */
struct work_struct connect_work; /* handle non-blocking connect*/
struct work_struct tcp_listen_work;/* handle tcp socket accepts */
struct work_struct smc_listen_work;/* prepare new accept socket */
struct list_head accept_q; /* sockets to be accepted */
spinlock_t accept_q_lock; /* protects accept_q */
bool limit_smc_hs; /* put constraint on handshake */
bool use_fallback; /* fallback to tcp */
int fallback_rsn; /* reason for fallback */
u32 peer_diagnosis; /* decline reason from peer */
atomic_t queued_smc_hs; /* queued smc handshakes */
struct inet_connection_sock_af_ops af_ops;
const struct inet_connection_sock_af_ops *ori_af_ops;
/* original af ops */
int sockopt_defer_accept;
/* sockopt TCP_DEFER_ACCEPT
* value
*/
u8 wait_close_tx_prepared : 1;
/* shutdown wr or close
* started, waiting for unsent
* data to be sent
*/
u8 connect_nonblock : 1;
/* non-blocking connect in
* flight
*/
struct mutex clcsock_release_lock;
/* protects clcsock of a listen
* socket
* */
};
static inline struct smc_sock *smc_sk(const struct sock *sk)
{
return (struct smc_sock *)sk;
}
static inline void smc_init_saved_callbacks(struct smc_sock *smc)
{
smc->clcsk_state_change = NULL;
smc->clcsk_data_ready = NULL;
smc->clcsk_write_space = NULL;
smc->clcsk_error_report = NULL;
}
static inline struct smc_sock *smc_clcsock_user_data(const struct sock *clcsk)
{
return (struct smc_sock *)
((uintptr_t)clcsk->sk_user_data & ~SK_USER_DATA_NOCOPY);
}
/* save target_cb in saved_cb, and replace target_cb with new_cb */
static inline void smc_clcsock_replace_cb(void (**target_cb)(struct sock *),
void (*new_cb)(struct sock *),
void (**saved_cb)(struct sock *))
{
/* only save once */
if (!*saved_cb)
*saved_cb = *target_cb;
*target_cb = new_cb;
}
/* restore target_cb to saved_cb, and reset saved_cb to NULL */
static inline void smc_clcsock_restore_cb(void (**target_cb)(struct sock *),
void (**saved_cb)(struct sock *))
{
if (!*saved_cb)
return;
*target_cb = *saved_cb;
*saved_cb = NULL;
}
extern struct workqueue_struct *smc_hs_wq; /* wq for handshake work */
extern struct workqueue_struct *smc_close_wq; /* wq for close work */
#define SMC_SYSTEMID_LEN 8
extern u8 local_systemid[SMC_SYSTEMID_LEN]; /* unique system identifier */
#define ntohll(x) be64_to_cpu(x)
#define htonll(x) cpu_to_be64(x)
/* convert an u32 value into network byte order, store it into a 3 byte field */
static inline void hton24(u8 *net, u32 host)
{
__be32 t;
t = cpu_to_be32(host);
memcpy(net, ((u8 *)&t) + 1, 3);
}
/* convert a received 3 byte field into host byte order*/
static inline u32 ntoh24(u8 *net)
{
__be32 t = 0;
memcpy(((u8 *)&t) + 1, net, 3);
return be32_to_cpu(t);
}
#ifdef CONFIG_XFRM
static inline bool using_ipsec(struct smc_sock *smc)
{
return (smc->clcsock->sk->sk_policy[0] ||
smc->clcsock->sk->sk_policy[1]) ? true : false;
}
#else
static inline bool using_ipsec(struct smc_sock *smc)
{
return false;
}
#endif
struct smc_gidlist;
struct sock *smc_accept_dequeue(struct sock *parent, struct socket *new_sock);
void smc_close_non_accepted(struct sock *sk);
void smc_fill_gid_list(struct smc_link_group *lgr,
struct smc_gidlist *gidlist,
struct smc_ib_device *known_dev, u8 *known_gid);
/* smc handshake limitation interface for netlink */
int smc_nl_dump_hs_limitation(struct sk_buff *skb, struct netlink_callback *cb);
int smc_nl_enable_hs_limitation(struct sk_buff *skb, struct genl_info *info);
int smc_nl_disable_hs_limitation(struct sk_buff *skb, struct genl_info *info);
#endif /* __SMC_H */