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freescale-linux-fslc/drivers/scsi/iscsi_tcp.h
Mike Christie 30a6c65236 [SCSI] iscsi: fix up iscsi eh
The current iscsi_tcp eh is not nicely setup for dm-multipath
and performs some extra task management functions when they
are not needed.

The attached patch:

- Fixes the TMF issues. If a session is rebuilt
then we do not send aborts.

- Fixes the problem where if the host reset fired, we would
return SUCCESS even though we had not really done anything
yet. This ends up causing problem with scsi_error.c's TUR.

- If someone has turned on the userspace nop daemon code to try
and detect network problems before the scsi command timeout
we can now drop and clean up the session before the scsi command
timesout and fires the eh speeding up the time it takes for a
command to go from one patch to another. For network problems
we fail the command with DID_BUS_BUSY so if failfast is set
scsi_decide_disposition fails the command up to dm for it to
try on another path.

- And we had to add some basic iscsi session block code. Previously
if we were trying to repair a session we would retrun a MLQUEUE code
in the queuecommand. This worked but it was not the most efficient
or pretty thing to do since it would take a while to relogin
to the target. For iscsi_tcp/open-iscsi a lot of the iscsi error handler
is in userspace the block code is pretty bare. We will be
adding to that for qla4xxx.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-04-14 14:05:09 -05:00

331 lines
9.9 KiB
C

/*
* 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 list_head run_list; /* list of cmds in progress */
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 */
int recovery_failed;
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 list_head running; /* running cmd list */
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 */