/* * iSCSI Initiator TCP Transport * Copyright (C) 2004 Dmitry Yusupov * Copyright (C) 2004 Alex Aizman * Copyright (C) 2005 - 2006 Mike Christie * Copyright (C) 2006 Red Hat, Inc. All rights reserved. * maintained by open-iscsi@googlegroups.com * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published * by the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * See the file COPYING included with this distribution for more details. */ #ifndef ISCSI_TCP_H #define ISCSI_TCP_H #include <scsi/libiscsi.h> /* Socket's Receive state machine */ #define IN_PROGRESS_WAIT_HEADER 0x0 #define IN_PROGRESS_HEADER_GATHER 0x1 #define IN_PROGRESS_DATA_RECV 0x2 #define IN_PROGRESS_DDIGEST_RECV 0x3 /* xmit state machine */ #define XMSTATE_IDLE 0x0 #define XMSTATE_R_HDR 0x1 #define XMSTATE_W_HDR 0x2 #define XMSTATE_IMM_HDR 0x4 #define XMSTATE_IMM_DATA 0x8 #define XMSTATE_UNS_INIT 0x10 #define XMSTATE_UNS_HDR 0x20 #define XMSTATE_UNS_DATA 0x40 #define XMSTATE_SOL_HDR 0x80 #define XMSTATE_SOL_DATA 0x100 #define XMSTATE_W_PAD 0x200 #define XMSTATE_W_RESEND_PAD 0x400 #define XMSTATE_W_RESEND_DATA_DIGEST 0x800 #define ISCSI_PAD_LEN 4 #define ISCSI_SG_TABLESIZE SG_ALL #define ISCSI_TCP_MAX_CMD_LEN 16 struct crypto_hash; struct socket; /* Socket connection recieve helper */ struct iscsi_tcp_recv { struct iscsi_hdr *hdr; struct sk_buff *skb; int offset; int len; int hdr_offset; int copy; int copied; int padding; struct iscsi_cmd_task *ctask; /* current cmd in progress */ /* copied and flipped values */ int datalen; int datadgst; char zero_copy_hdr; }; struct iscsi_tcp_conn { struct iscsi_conn *iscsi_conn; struct socket *sock; struct iscsi_hdr hdr; /* header placeholder */ char hdrext[4*sizeof(__u16) + sizeof(__u32)]; int data_copied; int stop_stage; /* conn_stop() flag: * * stop to recover, * * stop to terminate */ /* iSCSI connection-wide sequencing */ int hdr_size; /* PDU header size */ /* control data */ struct iscsi_tcp_recv in; /* TCP receive context */ int in_progress; /* connection state machine */ /* old values for socket callbacks */ void (*old_data_ready)(struct sock *, int); void (*old_state_change)(struct sock *); void (*old_write_space)(struct sock *); /* data and header digests */ struct hash_desc tx_hash; /* CRC32C (Tx) */ struct hash_desc rx_hash; /* CRC32C (Rx) */ /* MIB custom statistics */ uint32_t sendpage_failures_cnt; uint32_t discontiguous_hdr_cnt; ssize_t (*sendpage)(struct socket *, struct page *, int, size_t, int); }; struct iscsi_buf { struct scatterlist sg; unsigned int sent; char use_sendmsg; }; struct iscsi_data_task { struct iscsi_data hdr; /* PDU */ char hdrext[sizeof(__u32)]; /* Header-Digest */ struct iscsi_buf digestbuf; /* digest buffer */ uint32_t digest; /* data digest */ }; struct iscsi_tcp_mgmt_task { struct iscsi_hdr hdr; char hdrext[sizeof(__u32)]; /* Header-Digest */ int xmstate; /* mgmt xmit progress */ struct iscsi_buf headbuf; /* header buffer */ struct iscsi_buf sendbuf; /* in progress buffer */ int sent; }; struct iscsi_r2t_info { __be32 ttt; /* copied from R2T */ __be32 exp_statsn; /* copied from R2T */ uint32_t data_length; /* copied from R2T */ uint32_t data_offset; /* copied from R2T */ struct iscsi_buf headbuf; /* Data-Out Header Buffer */ struct iscsi_buf sendbuf; /* Data-Out in progress buffer*/ int sent; /* R2T sequence progress */ int data_count; /* DATA-Out payload progress */ struct scatterlist *sg; /* per-R2T SG list */ int solicit_datasn; struct iscsi_data_task dtask; /* which data task */ }; struct iscsi_tcp_cmd_task { struct iscsi_cmd hdr; char hdrext[4*sizeof(__u16)+ /* AHS */ sizeof(__u32)]; /* HeaderDigest */ char pad[ISCSI_PAD_LEN]; int pad_count; /* padded bytes */ struct iscsi_buf headbuf; /* header buf (xmit) */ struct iscsi_buf sendbuf; /* in progress buffer*/ int xmstate; /* xmit xtate machine */ int sent; struct scatterlist *sg; /* per-cmd SG list */ struct scatterlist *bad_sg; /* assert statement */ int sg_count; /* SG's to process */ uint32_t exp_r2tsn; int data_offset; struct iscsi_r2t_info *r2t; /* in progress R2T */ struct iscsi_queue r2tpool; struct kfifo *r2tqueue; struct iscsi_r2t_info **r2ts; int digest_count; uint32_t immdigest; /* for imm data */ struct iscsi_buf immbuf; /* for imm data digest */ struct iscsi_data_task unsol_dtask; /* unsol data task */ }; #endif /* ISCSI_H */