1 /* 2 * iSCSI Initiator TCP Transport 3 * Copyright (C) 2004 Dmitry Yusupov 4 * Copyright (C) 2004 Alex Aizman 5 * Copyright (C) 2005 - 2006 Mike Christie 6 * Copyright (C) 2006 Red Hat, Inc. All rights reserved. 7 * maintained by open-iscsi@googlegroups.com 8 * 9 * This program is free software; you can redistribute it and/or modify 10 * it under the terms of the GNU General Public License as published 11 * by the Free Software Foundation; either version 2 of the License, or 12 * (at your option) any later version. 13 * 14 * This program is distributed in the hope that it will be useful, but 15 * WITHOUT ANY WARRANTY; without even the implied warranty of 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 17 * General Public License for more details. 18 * 19 * See the file COPYING included with this distribution for more details. 20 */ 21 22 #ifndef ISCSI_TCP_H 23 #define ISCSI_TCP_H 24 25 #include <scsi/libiscsi.h> 26 27 struct crypto_hash; 28 struct socket; 29 struct iscsi_tcp_conn; 30 struct iscsi_segment; 31 32 typedef int iscsi_segment_done_fn_t(struct iscsi_tcp_conn *, 33 struct iscsi_segment *); 34 35 struct iscsi_segment { 36 unsigned char *data; 37 unsigned int size; 38 unsigned int copied; 39 unsigned int total_size; 40 unsigned int total_copied; 41 42 struct hash_desc *hash; 43 unsigned char recv_digest[ISCSI_DIGEST_SIZE]; 44 unsigned char digest[ISCSI_DIGEST_SIZE]; 45 unsigned int digest_len; 46 47 struct scatterlist *sg; 48 void *sg_mapped; 49 unsigned int sg_offset; 50 51 iscsi_segment_done_fn_t *done; 52 }; 53 54 /* Socket connection recieve helper */ 55 struct iscsi_tcp_recv { 56 struct iscsi_hdr *hdr; 57 struct iscsi_segment segment; 58 59 /* Allocate buffer for BHS + AHS */ 60 uint32_t hdr_buf[64]; 61 62 /* copied and flipped values */ 63 int datalen; 64 }; 65 66 /* Socket connection send helper */ 67 struct iscsi_tcp_send { 68 struct iscsi_hdr *hdr; 69 struct iscsi_segment segment; 70 struct iscsi_segment data_segment; 71 }; 72 73 struct iscsi_tcp_conn { 74 struct iscsi_conn *iscsi_conn; 75 struct socket *sock; 76 int stop_stage; /* conn_stop() flag: * 77 * stop to recover, * 78 * stop to terminate */ 79 /* control data */ 80 struct iscsi_tcp_recv in; /* TCP receive context */ 81 struct iscsi_tcp_send out; /* TCP send context */ 82 83 /* old values for socket callbacks */ 84 void (*old_data_ready)(struct sock *, int); 85 void (*old_state_change)(struct sock *); 86 void (*old_write_space)(struct sock *); 87 88 /* data and header digests */ 89 struct hash_desc tx_hash; /* CRC32C (Tx) */ 90 struct hash_desc rx_hash; /* CRC32C (Rx) */ 91 92 /* MIB custom statistics */ 93 uint32_t sendpage_failures_cnt; 94 uint32_t discontiguous_hdr_cnt; 95 96 int error; 97 98 ssize_t (*sendpage)(struct socket *, struct page *, int, size_t, int); 99 }; 100 101 struct iscsi_data_task { 102 struct iscsi_data hdr; /* PDU */ 103 char hdrext[ISCSI_DIGEST_SIZE];/* Header-Digest */ 104 }; 105 106 struct iscsi_r2t_info { 107 __be32 ttt; /* copied from R2T */ 108 __be32 exp_statsn; /* copied from R2T */ 109 uint32_t data_length; /* copied from R2T */ 110 uint32_t data_offset; /* copied from R2T */ 111 int sent; /* R2T sequence progress */ 112 int data_count; /* DATA-Out payload progress */ 113 int solicit_datasn; 114 struct iscsi_data_task dtask; /* Data-Out header buf */ 115 }; 116 117 struct iscsi_tcp_task { 118 struct iscsi_hdr_buff { 119 struct iscsi_cmd cmd_hdr; 120 char hdrextbuf[ISCSI_MAX_AHS_SIZE + 121 ISCSI_DIGEST_SIZE]; 122 } hdr; 123 124 int sent; 125 uint32_t exp_datasn; /* expected target's R2TSN/DataSN */ 126 int data_offset; 127 struct iscsi_r2t_info *r2t; /* in progress R2T */ 128 struct iscsi_pool r2tpool; 129 struct kfifo *r2tqueue; 130 struct iscsi_data_task unsol_dtask; /* Data-Out header buf */ 131 }; 132 133 #endif /* ISCSI_H */ 134