/* * iSCSI Initiator TCP Transport * Copyright (C) 2004 Dmitry Yusupov * Copyright (C) 2004 Alex Aizman * Copyright (C) 2005 Mike Christie * 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 /* Session's states */ #define ISCSI_STATE_FREE 1 #define ISCSI_STATE_LOGGED_IN 2 #define ISCSI_STATE_FAILED 3 #define ISCSI_STATE_TERMINATE 4 /* Connection's states */ #define ISCSI_CONN_INITIAL_STAGE 0 #define ISCSI_CONN_STARTED 1 #define ISCSI_CONN_STOPPED 2 #define ISCSI_CONN_CLEANUP_WAIT 3 /* Connection suspend "bit" */ #define SUSPEND_BIT 1 /* 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 /* Task Mgmt states */ #define TMABORT_INITIAL 0x0 #define TMABORT_SUCCESS 0x1 #define TMABORT_FAILED 0x2 #define TMABORT_TIMEDOUT 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_DATA_DIGEST 0x400 #define ISCSI_CONN_MAX 1 #define ISCSI_CONN_RCVBUF_MIN 262144 #define ISCSI_CONN_SNDBUF_MIN 262144 #define ISCSI_PAD_LEN 4 #define ISCSI_R2T_MAX 16 #define ISCSI_XMIT_CMDS_MAX 128 /* must be power of 2 */ #define ISCSI_MGMT_CMDS_MAX 32 /* must be power of 2 */ #define ISCSI_MGMT_ITT_OFFSET 0xa00 #define ISCSI_SG_TABLESIZE SG_ALL #define ISCSI_DEF_CMD_PER_LUN 32 #define ISCSI_MAX_CMD_PER_LUN 128 #define ISCSI_TCP_MAX_CMD_LEN 16 #define ITT_MASK (0xfff) #define CID_SHIFT 12 #define CID_MASK (0xffff<<CID_SHIFT) #define AGE_SHIFT 28 #define AGE_MASK (0xf<<AGE_SHIFT) struct iscsi_queue { struct kfifo *queue; /* FIFO Queue */ void **pool; /* Pool of elements */ int max; /* Max number of elements */ }; struct iscsi_session; struct iscsi_cmd_task; struct iscsi_mgmt_task; /* 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 opcode; int flags; int cmd_status; int ahslen; int datalen; uint32_t itt; int datadgst; }; struct iscsi_cls_conn; struct iscsi_conn { struct iscsi_cls_conn *cls_conn; /* ptr to class connection */ struct iscsi_hdr hdr; /* header placeholder */ char hdrext[4*sizeof(__u16) + sizeof(__u32)]; int data_copied; char *data; /* data placeholder */ struct socket *sock; /* TCP socket */ int data_size; /* actual recv_dlength */ int stop_stage; /* conn_stop() flag: * * stop to recover, * * stop to terminate */ /* iSCSI connection-wide sequencing */ uint32_t exp_statsn; int hdr_size; /* PDU header size */ unsigned long suspend_rx; /* suspend Rx */ struct crypto_tfm *rx_tfm; /* CRC32C (Rx) */ struct crypto_tfm *data_rx_tfm; /* CRC32C (Rx) for data */ /* control data */ int senselen; /* scsi sense length */ int id; /* CID */ struct iscsi_tcp_recv in; /* TCP receive context */ struct iscsi_session *session; /* parent session */ struct list_head item; /* maintains list of conns */ int in_progress; /* connection state machine */ int c_stage; /* connection state */ struct iscsi_mgmt_task *login_mtask; /* mtask used for login/text */ struct iscsi_mgmt_task *mtask; /* xmit mtask in progress */ struct iscsi_cmd_task *ctask; /* xmit ctask in progress */ /* old values for socket callbacks */ void (*old_data_ready)(struct sock *, int); void (*old_state_change)(struct sock *); void (*old_write_space)(struct sock *); /* xmit */ struct crypto_tfm *tx_tfm; /* CRC32C (Tx) */ struct crypto_tfm *data_tx_tfm; /* CRC32C (Tx) for data */ struct kfifo *writequeue; /* write cmds for Data-Outs */ struct kfifo *immqueue; /* immediate xmit queue */ struct kfifo *mgmtqueue; /* mgmt (control) xmit queue */ struct kfifo *xmitqueue; /* data-path cmd queue */ struct work_struct xmitwork; /* per-conn. xmit workqueue */ struct mutex xmitmutex; /* serializes connection xmit, * access to kfifos: * * xmitqueue, writequeue, * * immqueue, mgmtqueue */ unsigned long suspend_tx; /* suspend Tx */ /* abort */ wait_queue_head_t ehwait; /* used in eh_abort() */ struct iscsi_tm tmhdr; struct timer_list tmabort_timer; /* abort timer */ int tmabort_state; /* see TMABORT_INITIAL, etc.*/ /* negotiated params */ int max_recv_dlength; int max_xmit_dlength; int hdrdgst_en; int datadgst_en; /* MIB-statistics */ uint64_t txdata_octets; uint64_t rxdata_octets; uint32_t scsicmd_pdus_cnt; uint32_t dataout_pdus_cnt; uint32_t scsirsp_pdus_cnt; uint32_t datain_pdus_cnt; uint32_t r2t_pdus_cnt; uint32_t tmfcmd_pdus_cnt; int32_t tmfrsp_pdus_cnt; /* custom statistics */ uint32_t sendpage_failures_cnt; uint32_t discontiguous_hdr_cnt; uint32_t eh_abort_cnt; ssize_t (*sendpage)(struct socket *, struct page *, int, size_t, int); }; struct iscsi_session { /* iSCSI session-wide sequencing */ uint32_t cmdsn; uint32_t exp_cmdsn; uint32_t max_cmdsn; /* configuration */ int initial_r2t_en; int max_r2t; int imm_data_en; int first_burst; int max_burst; int time2wait; int time2retain; int pdu_inorder_en; int dataseq_inorder_en; int erl; int ifmarker_en; int ofmarker_en; /* control data */ struct Scsi_Host *host; int id; struct iscsi_conn *leadconn; /* leading connection */ spinlock_t lock; /* protects session state, * * sequence numbers, * * session resources: * * - cmdpool, * * - mgmtpool, * * - r2tpool */ int state; /* session state */ struct list_head item; void *auth_client; int conn_cnt; int age; /* counts session re-opens */ struct list_head connections; /* list of connections */ int cmds_max; /* size of cmds array */ struct iscsi_cmd_task **cmds; /* Original Cmds arr */ struct iscsi_queue cmdpool; /* PDU's pool */ int mgmtpool_max; /* size of mgmt array */ struct iscsi_mgmt_task **mgmt_cmds; /* Original mgmt arr */ struct iscsi_queue mgmtpool; /* Mgmt PDU's pool */ }; 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 list_head item; /* data queue item */ struct iscsi_buf digestbuf; /* digest buffer */ uint32_t digest; /* data digest */ }; #define ISCSI_DTASK_DEFAULT_MAX ISCSI_SG_TABLESIZE * PAGE_SIZE / 512 struct iscsi_mgmt_task { struct iscsi_hdr hdr; /* mgmt. PDU */ char hdrext[sizeof(__u32)]; /* Header-Digest */ char *data; /* mgmt payload */ int xmstate; /* mgmt xmit progress */ int data_count; /* counts data to be sent */ struct iscsi_buf headbuf; /* header buffer */ struct iscsi_buf sendbuf; /* in progress buffer */ int sent; uint32_t itt; /* this ITT */ }; 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_cmd_task { struct iscsi_cmd hdr; /* iSCSI PDU header */ char hdrext[4*sizeof(__u16)+ /* AHS */ sizeof(__u32)]; /* HeaderDigest */ char pad[ISCSI_PAD_LEN]; int itt; /* this ITT */ int datasn; /* DataSN */ struct iscsi_buf headbuf; /* header buf (xmit) */ struct iscsi_buf sendbuf; /* in progress buffer*/ int sent; struct scatterlist *sg; /* per-cmd SG list */ struct scatterlist *bad_sg; /* assert statement */ int sg_count; /* SG's to process */ uint32_t unsol_datasn; uint32_t exp_r2tsn; int xmstate; /* xmit xtate machine */ int imm_count; /* imm-data (bytes) */ int unsol_count; /* unsolicited (bytes)*/ int r2t_data_count; /* R2T Data-Out bytes */ int data_count; /* remaining Data-Out */ int pad_count; /* padded bytes */ struct scsi_cmnd *sc; /* associated SCSI cmd*/ int total_length; int data_offset; struct iscsi_conn *conn; /* used connection */ struct iscsi_mgmt_task *mtask; /* tmf mtask in progr */ struct iscsi_r2t_info *r2t; /* in progress R2T */ struct iscsi_queue r2tpool; struct kfifo *r2tqueue; struct iscsi_r2t_info **r2ts; struct list_head dataqueue; /* Data-Out dataqueue */ mempool_t *datapool; uint32_t datadigest; /* for recover digest */ int digest_count; uint32_t immdigest; /* for imm data */ struct iscsi_buf immbuf; /* for imm data digest */ struct iscsi_data_task *dtask; /* data task in progress*/ int digest_offset; /* for partial buff digest */ }; #endif /* ISCSI_H */