iscsi-target: Add iSCSI fabric support for target v4.1

The Linux-iSCSI.org target module is a full featured in-kernel
software implementation of iSCSI target mode (RFC-3720) for the
current WIP mainline target v4.1 infrastructure code for the v3.1
kernel.  More information can be found here:

http://linux-iscsi.org/wiki/ISCSI

This includes support for:

   * RFC-3720 defined request / response state machines and support for
     all defined iSCSI operation codes from Section 10.2.1.2 using libiscsi
     include/scsi/iscsi_proto.h PDU definitions
   * Target v4.1 compatible control plane using the generic layout in
     target_core_fabric_configfs.c and fabric dependent attributes
     within /sys/kernel/config/target/iscsi/ subdirectories.
   * Target v4.1 compatible iSCSI statistics based on RFC-4544 (iSCSI MIBS)
   * Support for IPv6 and IPv4 network portals in M:N mapping to TPGs
   * iSCSI Error Recovery Hierarchy support
   * Per iSCSI connection RX/TX thread pair scheduling affinity
   * crc32c + crc32c_intel SSEv4 instruction offload support using libcrypto
   * CHAP Authentication support using libcrypto
   * Conversion to use internal SGl allocation with iscsit_alloc_buffs() ->
     transport_generic_map_mem_to_cmd()

(nab: Fix iscsi_proto.h struct scsi_lun usage from linux-next in commit:
      iscsi: Use struct scsi_lun in iscsi structs instead of u8[8])
(nab: Fix 32-bit compile warnings)

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Andy Grover <agrover@redhat.com>
Acked-by: Roland Dreier <roland@kernel.org>
Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>

1 files changed, 86 insertions, 0 deletions

diff --git a/drivers/target/iscsi/iscsi_target_seq_pdu_list.h b/drivers/target/iscsi/iscsi_target_seq_pdu_list.h
new file mode 100644
index 00000000000..0d52a10e306
--- /dev/null
+++ b/drivers/target/iscsi/iscsi_target_seq_pdu_list.h
@@ -0,0 +1,86 @@
+#ifndef ISCSI_SEQ_AND_PDU_LIST_H
+#define ISCSI_SEQ_AND_PDU_LIST_H
+
+/* struct iscsi_pdu->status */
+#define DATAOUT_PDU_SENT			1
+
+/* struct iscsi_seq->type */
+#define SEQTYPE_IMMEDIATE			1
+#define SEQTYPE_UNSOLICITED			2
+#define SEQTYPE_NORMAL				3
+
+/* struct iscsi_seq->status */
+#define DATAOUT_SEQUENCE_GOT_R2T		1
+#define DATAOUT_SEQUENCE_WITHIN_COMMAND_RECOVERY 2
+#define DATAOUT_SEQUENCE_COMPLETE		3
+
+/* iscsi_determine_counts_for_list() type */
+#define PDULIST_NORMAL				1
+#define PDULIST_IMMEDIATE			2
+#define PDULIST_UNSOLICITED			3
+#define PDULIST_IMMEDIATE_AND_UNSOLICITED	4
+
+/* struct iscsi_pdu->type */
+#define PDUTYPE_IMMEDIATE			1
+#define PDUTYPE_UNSOLICITED			2
+#define PDUTYPE_NORMAL				3
+
+/* struct iscsi_pdu->status */
+#define ISCSI_PDU_NOT_RECEIVED			0
+#define ISCSI_PDU_RECEIVED_OK			1
+#define ISCSI_PDU_CRC_FAILED			2
+#define ISCSI_PDU_TIMED_OUT			3
+
+/* struct iscsi_build_list->randomize */
+#define RANDOM_DATAIN_PDU_OFFSETS		0x01
+#define RANDOM_DATAIN_SEQ_OFFSETS		0x02
+#define RANDOM_DATAOUT_PDU_OFFSETS		0x04
+#define RANDOM_R2T_OFFSETS			0x08
+
+/* struct iscsi_build_list->data_direction */
+#define ISCSI_PDU_READ				0x01
+#define ISCSI_PDU_WRITE				0x02
+
+struct iscsi_build_list {
+	int		data_direction;
+	int		randomize;
+	int		type;
+	int		immediate_data_length;
+};
+
+struct iscsi_pdu {
+	int		status;
+	int		type;
+	u8		flags;
+	u32		data_sn;
+	u32		length;
+	u32		offset;
+	u32		pdu_send_order;
+	u32		seq_no;
+} ____cacheline_aligned;
+
+struct iscsi_seq {
+	int		sent;
+	int		status;
+	int		type;
+	u32		data_sn;
+	u32		first_datasn;
+	u32		last_datasn;
+	u32		next_burst_len;
+	u32		pdu_start;
+	u32		pdu_count;
+	u32		offset;
+	u32		orig_offset;
+	u32		pdu_send_order;
+	u32		r2t_sn;
+	u32		seq_send_order;
+	u32		seq_no;
+	u32		xfer_len;
+} ____cacheline_aligned;
+
+extern int iscsit_do_build_list(struct iscsi_cmd *, struct iscsi_build_list *);
+extern struct iscsi_pdu *iscsit_get_pdu_holder(struct iscsi_cmd *, u32, u32);
+extern struct iscsi_pdu *iscsit_get_pdu_holder_for_seq(struct iscsi_cmd *, struct iscsi_seq *);
+extern struct iscsi_seq *iscsit_get_seq_holder(struct iscsi_cmd *, u32, u32);
+
+#endif /* ISCSI_SEQ_AND_PDU_LIST_H */