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Release 4.11 net/smc/smc.h

Directory: net/smc
/*
 *  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/sock.h>

#include "smc_ib.h"


#define SMCPROTO_SMC		0	
/* SMC protocol */


#define SMC_MAX_PORTS		2	
/* Max # of ports */

extern struct proto smc_proto;

#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 */
	
u8			type;
} __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);


struct smc_connection {
	
struct rb_node		alert_node;
	
struct smc_link_group	*lgr;		/* link group of connection */
	
u32			alert_token_local; /* unique conn. id */
	
u8			peer_conn_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 */
	
int			sndbuf_size;	/* sndbuf size <== sock wmem */
	
struct smc_buf_desc	*rmb_desc;	/* RMBE descriptor */
	
int			rmbe_size;	/* RMBE size <== sock rmem */
	
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	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 */
	
spinlock_t		send_lock;	/* protect wr_sends */
	
struct work_struct	tx_work;	/* retry of smc_cdc_msg_send */

	
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 ?
                                                    */
	
atomic_t		bytes_to_rcv;	/* arrived data,
                                                 * not yet received
                                                 */
#ifndef KERNEL_HAS_ATOMIC64
	
spinlock_t		acurs_lock;	/* protect cursors */
#endif
};


struct smc_sock {				/* smc sock container */
	
struct sock		sk;
	
struct socket		*clcsock;	/* internal tcp socket */
	
struct smc_connection	conn;		/* smc connection */
	
struct sockaddr		*addr;		/* inet connect address */
	
struct smc_sock		*listen_smc;	/* listen parent */
	
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 */
	
struct delayed_work	sock_put_work;	/* final socket freeing */
	
bool			use_fallback;	/* fallback to tcp */
	
u8			wait_close_tx_prepared : 1;
						/* shutdown wr or close
                                                 * started, waiting for unsent
                                                 * data to be sent
                                                 */
};


static inline struct smc_sock *smc_sk(const struct sock *sk) { return (struct smc_sock *)sk; }

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#define SMC_SYSTEMID_LEN 8 extern u8 local_systemid[SMC_SYSTEMID_LEN]; /* unique system identifier */ /* 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); }

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/* 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); }

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#define SMC_BUF_MIN_SIZE 16384 /* minimum size of an RMB */ #define SMC_RMBE_SIZES 16 /* number of distinct sizes for an RMBE */ /* theoretically, the RFC states that largest size would be 512K, * i.e. compressed 5 and thus 6 sizes (0..5), despite * struct smc_clc_msg_accept_confirm.rmbe_size being a 4 bit value (0..15) */ /* convert the RMB size into the compressed notation - minimum 16K. * In contrast to plain ilog2, this rounds towards the next power of 2, * so the socket application gets at least its desired sndbuf / rcvbuf size. */
static inline u8 smc_compress_bufsize(int size) { u8 compressed; if (size <= SMC_BUF_MIN_SIZE) return 0; size = (size - 1) >> 14; compressed = ilog2(size) + 1; if (compressed >= SMC_RMBE_SIZES) compressed = SMC_RMBE_SIZES - 1; return compressed; }

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/* convert the RMB size from compressed notation into integer */
static inline int smc_uncompress_bufsize(u8 compressed) { u32 size; size = 0x00000001 << (((int)compressed) + 14); return (int)size; }

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#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]) ? 1 : 0; }

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#else
static inline bool using_ipsec(struct smc_sock *smc) { return 0; }

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#endif struct smc_clc_msg_local; int smc_netinfo_by_tcpsk(struct socket *clcsock, __be32 *subnet, u8 *prefix_len); void smc_conn_free(struct smc_connection *conn); int smc_conn_create(struct smc_sock *smc, __be32 peer_in_addr, struct smc_ib_device *smcibdev, u8 ibport, struct smc_clc_msg_local *lcl, int srv_first_contact); struct sock *smc_accept_dequeue(struct sock *parent, struct socket *new_sock); void smc_close_non_accepted(struct sock *sk); #endif /* __SMC_H */

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Directory: net/smc
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