[SCSI] libiscsi, iscsi_tcp: add device support

This patch adds logical unit reset support. This should work for ib_iser,
but I have not finished testing that driver so it is not hooked in yet.

This patch also temporarily reverts the iscsi_tcp r2t write out patch.
That code is completely rewritten in this patchset.
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

drivers/infiniband/ulp/iser/iscsi_iser.c

@@ -220,12 +220,6 @@ iscsi_iser_ctask_xmit(struct iscsi_conn *conn,
 	debug_scsi("ctask deq [cid %d itt 0x%x]\n",
 		   conn->id, ctask->itt);
 
-	/*
-	 * serialize with TMF AbortTask
-	 */
-	if (ctask->mtask)
-		return error;
-
 	/* Send the cmd PDU */
 	if (!iser_ctask->command_sent) {
 		error = iser_send_command(conn, ctask);

drivers/scsi/iscsi_tcp.h

@@ -32,21 +32,21 @@
 #define IN_PROGRESS_PAD_RECV		0x4
 
 /* xmit state machine */
-#define XMSTATE_VALUE_IDLE			0
-#define XMSTATE_BIT_CMD_HDR_INIT		0
-#define XMSTATE_BIT_CMD_HDR_XMIT		1
-#define XMSTATE_BIT_IMM_HDR			2
-#define XMSTATE_BIT_IMM_DATA			3
-#define XMSTATE_BIT_UNS_INIT			4
-#define XMSTATE_BIT_UNS_HDR			5
-#define XMSTATE_BIT_UNS_DATA			6
-#define XMSTATE_BIT_SOL_HDR			7
-#define XMSTATE_BIT_SOL_DATA			8
-#define XMSTATE_BIT_W_PAD			9
-#define XMSTATE_BIT_W_RESEND_PAD		10
-#define XMSTATE_BIT_W_RESEND_DATA_DIGEST	11
-#define XMSTATE_BIT_IMM_HDR_INIT		12
-#define XMSTATE_BIT_SOL_HDR_INIT		13
+#define XMSTATE_IDLE			0x0
+#define XMSTATE_CMD_HDR_INIT		0x1
+#define XMSTATE_CMD_HDR_XMIT		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 XMSTATE_IMM_HDR_INIT		0x1000
+#define XMSTATE_SOL_HDR_INIT		0x2000
 
 #define ISCSI_PAD_LEN			4
 #define ISCSI_SG_TABLESIZE		SG_ALL
@@ -122,7 +122,7 @@ struct iscsi_data_task {
 struct iscsi_tcp_mgmt_task {
 	struct iscsi_hdr	hdr;
 	char			hdrext[sizeof(__u32)]; /* Header-Digest */
-	unsigned long		xmstate;	/* mgmt xmit progress */
+	int			xmstate;	/* mgmt xmit progress */
 	struct iscsi_buf	headbuf;	/* header buffer */
 	struct iscsi_buf	sendbuf;	/* in progress buffer */
 	int			sent;
@@ -150,7 +150,7 @@ struct iscsi_tcp_cmd_task {
 	int			pad_count;		/* padded bytes */
 	struct iscsi_buf	headbuf;		/* header buf (xmit) */
 	struct iscsi_buf	sendbuf;		/* in progress buffer*/
-	unsigned long		xmstate;		/* xmit xtate machine */
+	int			xmstate;		/* xmit xtate machine */
 	int			sent;
 	struct scatterlist	*sg;			/* per-cmd SG list  */
 	struct scatterlist	*bad_sg;		/* assert statement */

drivers/scsi/scsi_transport_iscsi.c

@@ -30,7 +30,7 @@
 #include <scsi/scsi_transport_iscsi.h>
 #include <scsi/iscsi_if.h>
 
-#define ISCSI_SESSION_ATTRS 15
+#define ISCSI_SESSION_ATTRS 16
 #define ISCSI_CONN_ATTRS 11
 #define ISCSI_HOST_ATTRS 4
 #define ISCSI_TRANSPORT_VERSION "2.0-724"
@@ -1218,6 +1218,7 @@ iscsi_session_attr(username, ISCSI_PARAM_USERNAME, 1);
 iscsi_session_attr(username_in, ISCSI_PARAM_USERNAME_IN, 1);
 iscsi_session_attr(password, ISCSI_PARAM_PASSWORD, 1);
 iscsi_session_attr(password_in, ISCSI_PARAM_PASSWORD_IN, 1);
+iscsi_session_attr(fast_abort, ISCSI_PARAM_FAST_ABORT, 1);
 
 #define iscsi_priv_session_attr_show(field, format)			\
 static ssize_t								\
@@ -1439,6 +1440,7 @@ iscsi_register_transport(struct iscsi_transport *tt)
 	SETUP_SESSION_RD_ATTR(password_in, ISCSI_USERNAME_IN);
 	SETUP_SESSION_RD_ATTR(username, ISCSI_PASSWORD);
 	SETUP_SESSION_RD_ATTR(username_in, ISCSI_PASSWORD_IN);
+	SETUP_SESSION_RD_ATTR(fast_abort, ISCSI_FAST_ABORT);
 	SETUP_PRIV_SESSION_RD_ATTR(recovery_tmo);
 
 	BUG_ON(count > ISCSI_SESSION_ATTRS);

include/scsi/iscsi_if.h

@@ -236,6 +236,7 @@ enum iscsi_param {
 	ISCSI_PARAM_PASSWORD,
 	ISCSI_PARAM_PASSWORD_IN,
 
+	ISCSI_PARAM_FAST_ABORT,
 	/* must always be last */
 	ISCSI_PARAM_MAX,
 };
@@ -266,6 +267,7 @@ enum iscsi_param {
 #define ISCSI_USERNAME_IN		(1 << ISCSI_PARAM_USERNAME_IN)
 #define ISCSI_PASSWORD			(1 << ISCSI_PARAM_PASSWORD)
 #define ISCSI_PASSWORD_IN		(1 << ISCSI_PARAM_PASSWORD_IN)
+#define ISCSI_FAST_ABORT		(1 << ISCSI_PARAM_FAST_ABORT)
 
 /* iSCSI HBA params */
 enum iscsi_host_param {

include/scsi/iscsi_proto.h

@@ -600,6 +600,8 @@ struct iscsi_reject {
 #define ISCSI_MIN_MAX_BURST_LEN			512
 #define ISCSI_MAX_MAX_BURST_LEN			16777215
 
+#define ISCSI_DEF_TIME2WAIT			2
+
 /************************* RFC 3720 End *****************************/
 
 #endif /* ISCSI_PROTO_H */

include/scsi/libiscsi.h

@@ -57,11 +57,14 @@ struct iscsi_nopin;
 #define ISCSI_MAX_CMD_PER_LUN		128
 
 /* Task Mgmt states */
-#define TMABORT_INITIAL			0x0
-#define TMABORT_SUCCESS			0x1
-#define TMABORT_FAILED			0x2
-#define TMABORT_TIMEDOUT		0x3
-#define TMABORT_NOT_FOUND		0x4
+enum {
+	TMF_INITIAL,
+	TMF_QUEUED,
+	TMF_SUCCESS,
+	TMF_FAILED,
+	TMF_TIMEDOUT,
+	TMF_NOT_FOUND,
+};
 
 /* Connection suspend "bit" */
 #define ISCSI_SUSPEND_BIT		1
@@ -91,7 +94,6 @@ enum {
 	ISCSI_TASK_COMPLETED,
 	ISCSI_TASK_PENDING,
 	ISCSI_TASK_RUNNING,
-	ISCSI_TASK_ABORTING,
 };
 
 struct iscsi_cmd_task {
@@ -110,7 +112,6 @@ struct iscsi_cmd_task {
 	unsigned		data_count;	/* remaining Data-Out */
 	struct scsi_cmnd	*sc;		/* associated SCSI cmd*/
 	struct iscsi_conn	*conn;		/* used connection    */
-	struct iscsi_mgmt_task	*mtask;		/* tmf mtask in progr */
 
 	/* state set/tested under session->lock */
 	int			state;
@@ -152,10 +153,11 @@ struct iscsi_conn {
 	struct iscsi_cmd_task	*ctask;		/* xmit ctask in progress */
 
 	/* xmit */
-	struct kfifo		*mgmtqueue;	/* mgmt (control) xmit queue */
+	struct list_head	mgmtqueue;	/* mgmt (control) xmit queue */
 	struct list_head	mgmt_run_list;	/* list of control tasks */
 	struct list_head	xmitqueue;	/* data-path cmd queue */
 	struct list_head	run_list;	/* list of cmds in progress */
+	struct list_head	requeue;	/* tasks needing another run */
 	struct work_struct	xmitwork;	/* per-conn. xmit workqueue */
 	unsigned long		suspend_tx;	/* suspend Tx */
 	unsigned long		suspend_rx;	/* suspend Rx */
@@ -163,8 +165,8 @@ struct iscsi_conn {
 	/* abort */
 	wait_queue_head_t	ehwait;		/* used in eh_abort() */
 	struct iscsi_tm		tmhdr;
-	struct timer_list	tmabort_timer;
-	int			tmabort_state;	/* see TMABORT_INITIAL, etc.*/
+	struct timer_list	tmf_timer;
+	int			tmf_state;	/* see TMF_INITIAL, etc.*/
 
 	/* negotiated params */
 	unsigned		max_recv_dlength; /* initiator_max_recv_dsl*/
@@ -231,6 +233,7 @@ struct iscsi_session {
 	int			pdu_inorder_en;
 	int			dataseq_inorder_en;
 	int			erl;
+	int			fast_abort;
 	int			tpgt;
 	char			*username;
 	char			*username_in;
@@ -268,6 +271,7 @@ struct iscsi_session {
 extern int iscsi_change_queue_depth(struct scsi_device *sdev, int depth);
 extern int iscsi_eh_abort(struct scsi_cmnd *sc);
 extern int iscsi_eh_host_reset(struct scsi_cmnd *sc);
+extern int iscsi_eh_device_reset(struct scsi_cmnd *sc);
 extern int iscsi_queuecommand(struct scsi_cmnd *sc,
 			      void (*done)(struct scsi_cmnd *));
 
@@ -326,6 +330,7 @@ extern int __iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
 				char *, int);
 extern int iscsi_verify_itt(struct iscsi_conn *, struct iscsi_hdr *,
 			    uint32_t *);
+extern void iscsi_requeue_ctask(struct iscsi_cmd_task *ctask);
 
 /*
  * generic helpers