1 /* 2 * iSCSI over TCP/IP Data-Path lib 3 * 4 * Copyright (C) 2008 Mike Christie 5 * Copyright (C) 2008 Red Hat, Inc. All rights reserved. 6 * maintained by open-iscsi@googlegroups.com 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License as published 10 * by the Free Software Foundation; either version 2 of the License, or 11 * (at your option) any later version. 12 * 13 * This program is distributed in the hope that it will be useful, but 14 * WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 16 * General Public License for more details. 17 * 18 * See the file COPYING included with this distribution for more details. 19 */ 20 21 #ifndef LIBISCSI_TCP_H 22 #define LIBISCSI_TCP_H 23 24 #include <scsi/libiscsi.h> 25 26 struct iscsi_tcp_conn; 27 struct iscsi_segment; 28 struct sk_buff; 29 struct hash_desc; 30 31 typedef int iscsi_segment_done_fn_t(struct iscsi_tcp_conn *, 32 struct iscsi_segment *); 33 34 struct iscsi_segment { 35 unsigned char *data; 36 unsigned int size; 37 unsigned int copied; 38 unsigned int total_size; 39 unsigned int total_copied; 40 41 struct hash_desc *hash; 42 unsigned char padbuf[ISCSI_PAD_LEN]; 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 struct iscsi_tcp_conn { 67 struct iscsi_conn *iscsi_conn; 68 void *dd_data; 69 int stop_stage; /* conn_stop() flag: * 70 * stop to recover, * 71 * stop to terminate */ 72 /* control data */ 73 struct iscsi_tcp_recv in; /* TCP receive context */ 74 /* CRC32C (Rx) LLD should set this is they do not offload */ 75 struct hash_desc *rx_hash; 76 }; 77 78 struct iscsi_tcp_task { 79 uint32_t exp_datasn; /* expected target's R2TSN/DataSN */ 80 int data_offset; 81 struct iscsi_r2t_info *r2t; /* in progress solict R2T */ 82 struct iscsi_pool r2tpool; 83 struct kfifo r2tqueue; 84 void *dd_data; 85 }; 86 87 enum { 88 ISCSI_TCP_SEGMENT_DONE, /* curr seg has been processed */ 89 ISCSI_TCP_SKB_DONE, /* skb is out of data */ 90 ISCSI_TCP_CONN_ERR, /* iscsi layer has fired a conn err */ 91 ISCSI_TCP_SUSPENDED, /* conn is suspended */ 92 }; 93 94 extern void iscsi_tcp_hdr_recv_prep(struct iscsi_tcp_conn *tcp_conn); 95 extern int iscsi_tcp_recv_skb(struct iscsi_conn *conn, struct sk_buff *skb, 96 unsigned int offset, bool offloaded, int *status); 97 extern void iscsi_tcp_cleanup_task(struct iscsi_task *task); 98 extern int iscsi_tcp_task_init(struct iscsi_task *task); 99 extern int iscsi_tcp_task_xmit(struct iscsi_task *task); 100 101 /* segment helpers */ 102 extern int iscsi_tcp_recv_segment_is_hdr(struct iscsi_tcp_conn *tcp_conn); 103 extern int iscsi_tcp_segment_done(struct iscsi_tcp_conn *tcp_conn, 104 struct iscsi_segment *segment, int recv, 105 unsigned copied); 106 extern void iscsi_tcp_segment_unmap(struct iscsi_segment *segment); 107 108 extern void iscsi_segment_init_linear(struct iscsi_segment *segment, 109 void *data, size_t size, 110 iscsi_segment_done_fn_t *done, 111 struct hash_desc *hash); 112 extern int 113 iscsi_segment_seek_sg(struct iscsi_segment *segment, 114 struct scatterlist *sg_list, unsigned int sg_count, 115 unsigned int offset, size_t size, 116 iscsi_segment_done_fn_t *done, struct hash_desc *hash); 117 118 /* digest helpers */ 119 extern void iscsi_tcp_dgst_header(struct hash_desc *hash, const void *hdr, 120 size_t hdrlen, 121 unsigned char digest[ISCSI_DIGEST_SIZE]); 122 extern struct iscsi_cls_conn * 123 iscsi_tcp_conn_setup(struct iscsi_cls_session *cls_session, int dd_data_size, 124 uint32_t conn_idx); 125 extern void iscsi_tcp_conn_teardown(struct iscsi_cls_conn *cls_conn); 126 127 /* misc helpers */ 128 extern int iscsi_tcp_r2tpool_alloc(struct iscsi_session *session); 129 extern void iscsi_tcp_r2tpool_free(struct iscsi_session *session); 130 131 extern void iscsi_tcp_conn_get_stats(struct iscsi_cls_conn *cls_conn, 132 struct iscsi_stats *stats); 133 #endif /* LIBISCSI_TCP_H */ 134