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[12/14] ./block/iscsi/*.h

Message ID 1291374593-17448-13-git-send-email-ronniesahlberg@gmail.com
State New
Headers show

Commit Message

ronnie sahlberg Dec. 3, 2010, 11:09 a.m. UTC
From: Ronnie Sahlberg <ronniesahlberg@gmail.com>

iscsi  client library  : *.h
These files contain the heade declaraions, typedefs and useful macros
used by the iscsi client library.

...

./block/iscsi/ contains a copy of a general purpose iscsi client
library which is aimed at providing a clientside api for iscsi
for both qemu/kvm as well as otther scsi related utilities.

As such, there is need to make merging across various consumers,
qemu/kvm being one of many here, as easy as possible when features
are added to the library.
As such, no consumer/qemu specific code is used in this library as well
as coding guidelined might not be adhered to 100%

It is the intention that this library will be useful for many
and that iscsi use spawned from this will flourish.

Signed-off-by: Ronnie Sahlberg <ronniesahlberg@gmail.com>
---
 block/iscsi/iscsi-private.h |  172 +++++++++++++++++
 block/iscsi/iscsi.h         |  433 +++++++++++++++++++++++++++++++++++++++++++
 block/iscsi/scsi-lowlevel.h |  369 ++++++++++++++++++++++++++++++++++++
 block/iscsi/slist.h         |   51 +++++
 4 files changed, 1025 insertions(+), 0 deletions(-)
 create mode 100644 block/iscsi/iscsi-private.h
 create mode 100644 block/iscsi/iscsi.h
 create mode 100644 block/iscsi/scsi-lowlevel.h
 create mode 100644 block/iscsi/slist.h
diff mbox

Patch

diff --git a/block/iscsi/iscsi-private.h b/block/iscsi/iscsi-private.h
new file mode 100644
index 0000000..ef1d02f
--- /dev/null
+++ b/block/iscsi/iscsi-private.h
@@ -0,0 +1,172 @@ 
+/*
+   Copyright (C) 2010 by Ronnie Sahlberg <ronniesahlberg@gmail.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.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include <stdint.h>
+
+#ifndef discard_const
+#define discard_const(ptr) ((void *)((intptr_t)(ptr)))
+#endif
+
+struct iscsi_context {
+	const char *initiator_name;
+	const char *target_name;
+	const char *alias;
+	enum iscsi_session_type session_type;
+	unsigned char isid[6];
+	uint32_t itt;
+	uint32_t cmdsn;
+	uint32_t statsn;
+	enum iscsi_header_digest want_header_digest;
+	enum iscsi_header_digest header_digest;
+
+	char *error_string;
+
+	int fd;
+	int is_connected;
+	int is_loggedin;
+
+	iscsi_command_cb connect_cb;
+	void *connect_data;
+
+	struct iscsi_pdu *outqueue;
+	struct iscsi_pdu *waitpdu;
+
+	int insize;
+	int inpos;
+	unsigned char *inbuf;
+};
+
+#define ISCSI_RAW_HEADER_SIZE			48
+
+#define ISCSI_HEADER_SIZE (ISCSI_RAW_HEADER_SIZE	\
+  + (iscsi->header_digest == ISCSI_HEADER_DIGEST_NONE?0:4))
+
+#define ISCSI_PDU_IMMEDIATE		       0x40
+
+#define ISCSI_PDU_TEXT_FINAL		       0x80
+#define ISCSI_PDU_TEXT_CONTINUE		       0x40
+
+#define ISCSI_PDU_LOGIN_TRANSIT		       0x80
+#define ISCSI_PDU_LOGIN_CONTINUE	       0x40
+#define ISCSI_PDU_LOGIN_CSG_SECNEG	       0x00
+#define ISCSI_PDU_LOGIN_CSG_OPNEG	       0x04
+#define ISCSI_PDU_LOGIN_CSG_FF		       0x0c
+#define ISCSI_PDU_LOGIN_NSG_SECNEG	       0x00
+#define ISCSI_PDU_LOGIN_NSG_OPNEG	       0x01
+#define ISCSI_PDU_LOGIN_NSG_FF		       0x03
+
+#define ISCSI_PDU_SCSI_FINAL		       0x80
+#define ISCSI_PDU_SCSI_READ		       0x40
+#define ISCSI_PDU_SCSI_WRITE		       0x20
+#define ISCSI_PDU_SCSI_ATTR_UNTAGGED	       0x00
+#define ISCSI_PDU_SCSI_ATTR_SIMPLE	       0x01
+#define ISCSI_PDU_SCSI_ATTR_ORDERED	       0x02
+#define ISCSI_PDU_SCSI_ATTR_HEADOFQUEUE	       0x03
+#define ISCSI_PDU_SCSI_ATTR_ACA		       0x04
+
+#define ISCSI_PDU_DATA_FINAL		       0x80
+#define ISCSI_PDU_DATA_ACK_REQUESTED	       0x40
+#define ISCSI_PDU_DATA_BIDIR_OVERFLOW  	       0x10
+#define ISCSI_PDU_DATA_BIDIR_UNDERFLOW         0x08
+#define ISCSI_PDU_DATA_RESIDUAL_OVERFLOW       0x04
+#define ISCSI_PDU_DATA_RESIDUAL_UNDERFLOW      0x02
+#define ISCSI_PDU_DATA_CONTAINS_STATUS	       0x01
+
+enum iscsi_opcode {
+	ISCSI_PDU_NOP_OUT         = 0x00,
+	ISCSI_PDU_SCSI_REQUEST    = 0x01,
+	ISCSI_PDU_LOGIN_REQUEST   = 0x03,
+	ISCSI_PDU_TEXT_REQUEST    = 0x04,
+	ISCSI_PDU_LOGOUT_REQUEST  = 0x06,
+	ISCSI_PDU_NOP_IN          = 0x20,
+	ISCSI_PDU_SCSI_RESPONSE   = 0x21,
+	ISCSI_PDU_LOGIN_RESPONSE  = 0x23,
+	ISCSI_PDU_TEXT_RESPONSE   = 0x24,
+	ISCSI_PDU_DATA_IN         = 0x25,
+	ISCSI_PDU_LOGOUT_RESPONSE = 0x26
+};
+
+struct iscsi_pdu {
+	struct iscsi_pdu *next;
+
+	uint32_t itt;
+	uint32_t cmdsn;
+	enum iscsi_opcode response_opcode;
+
+	iscsi_command_cb callback;
+	void *private_data;
+
+	int written;
+	struct iscsi_data outdata;
+	struct iscsi_data indata;
+
+	struct iscsi_scsi_cbdata *scsi_cbdata;
+};
+
+void iscsi_free_scsi_cbdata(struct iscsi_scsi_cbdata *scsi_cbdata);
+
+struct iscsi_pdu *iscsi_allocate_pdu(struct iscsi_context *iscsi,
+				     enum iscsi_opcode opcode,
+				     enum iscsi_opcode response_opcode);
+void iscsi_free_pdu(struct iscsi_context *iscsi, struct iscsi_pdu *pdu);
+void iscsi_pdu_set_pduflags(struct iscsi_pdu *pdu, unsigned char flags);
+void iscsi_pdu_set_immediate(struct iscsi_pdu *pdu);
+void iscsi_pdu_set_ttt(struct iscsi_pdu *pdu, uint32_t ttt);
+void iscsi_pdu_set_cmdsn(struct iscsi_pdu *pdu, uint32_t cmdsn);
+void iscsi_pdu_set_lun(struct iscsi_pdu *pdu, uint32_t lun);
+void iscsi_pdu_set_expstatsn(struct iscsi_pdu *pdu, uint32_t expstatsnsn);
+void iscsi_pdu_set_expxferlen(struct iscsi_pdu *pdu, uint32_t expxferlen);
+int iscsi_pdu_add_data(struct iscsi_context *iscsi, struct iscsi_pdu *pdu,
+		       unsigned char *dptr, int dsize);
+int iscsi_queue_pdu(struct iscsi_context *iscsi, struct iscsi_pdu *pdu);
+int iscsi_add_data(struct iscsi_context *iscsi, struct iscsi_data *data,
+		   unsigned char *dptr, int dsize, int pdualignment);
+int iscsi_set_random_isid(struct iscsi_context *iscsi);
+
+struct scsi_task;
+void iscsi_pdu_set_cdb(struct iscsi_pdu *pdu, struct scsi_task *task);
+
+int iscsi_get_pdu_size(struct iscsi_context *iscsi, const unsigned char *hdr);
+int iscsi_process_pdu(struct iscsi_context *iscsi, const unsigned char *hdr,
+		      int size);
+
+int iscsi_process_login_reply(struct iscsi_context *iscsi,
+			      struct iscsi_pdu *pdu,
+			      const unsigned char *hdr, int size);
+int iscsi_process_text_reply(struct iscsi_context *iscsi,
+			     struct iscsi_pdu *pdu,
+			     const unsigned char *hdr, int size);
+int iscsi_process_logout_reply(struct iscsi_context *iscsi,
+			       struct iscsi_pdu *pdu,
+			       const unsigned char *hdr, int size);
+int iscsi_process_scsi_reply(struct iscsi_context *iscsi,
+			     struct iscsi_pdu *pdu,
+			     const unsigned char *hdr, int size);
+int iscsi_process_scsi_data_in(struct iscsi_context *iscsi,
+			       struct iscsi_pdu *pdu,
+			       const unsigned char *hdr, int size,
+			       int *is_finished);
+int iscsi_process_nop_out_reply(struct iscsi_context *iscsi,
+				struct iscsi_pdu *pdu,
+				const unsigned char *hdr, int size);
+
+void iscsi_set_error(struct iscsi_context *iscsi, const char *error_string,
+		     ...);
+
+unsigned long crc32c(char *buf, int len);
+
+void iscsi_cbdata_steal_scsi_task(struct scsi_task *task);
diff --git a/block/iscsi/iscsi.h b/block/iscsi/iscsi.h
new file mode 100644
index 0000000..5e4c2cc
--- /dev/null
+++ b/block/iscsi/iscsi.h
@@ -0,0 +1,433 @@ 
+/*
+   Copyright (C) 2010 by Ronnie Sahlberg <ronniesahlberg@gmail.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.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, see <http://www.gnu.org/licenses/>.
+*/
+
+struct iscsi_context;
+struct sockaddr;
+
+
+char *iscsi_get_error(struct iscsi_context *iscsi);
+
+/*
+ * Returns the file descriptor that libiscsi uses.
+ */
+int iscsi_get_fd(struct iscsi_context *iscsi);
+
+/*
+ * Returns which events that we need to poll for for the iscsi file descriptor.
+ */
+int iscsi_which_events(struct iscsi_context *iscsi);
+
+/*
+ * Called to process the events when events become available for the iscsi
+ * file descriptor.
+ */
+int iscsi_service(struct iscsi_context *iscsi, int revents);
+
+
+
+/*
+ * Create a context for an ISCSI session.
+ * Initiator_name is the iqn name we want to identify to the target as.
+ *
+ * Returns:
+ *  0: success
+ * <0: error
+ */
+struct iscsi_context *iscsi_create_context(const char *initiator_name);
+
+/*
+ * Destroy an existing ISCSI context and tear down any existing connection.
+ * Callbacks for any command in flight will be invoked with
+ * ISCSI_STATUS_CANCELLED.
+ *
+ * Returns:
+ *  0: success
+ * <0: error
+ */
+int iscsi_destroy_context(struct iscsi_context *iscsi);
+
+/*
+ * Set an optional alias name to identify with when connecting to the target
+ *
+ * Returns:
+ *  0: success
+ * <0: error
+ */
+int iscsi_set_alias(struct iscsi_context *iscsi, const char *alias);
+
+/*
+ * Set the iqn name of the taqget to login to.
+ * The target name must be set before a normal-login can be initiated.
+ * Only discovery-logins are possible without setting the target iqn name.
+ *
+ * Returns:
+ *  0: success
+ * <0: error
+ */
+int iscsi_set_targetname(struct iscsi_context *iscsi, const char *targetname);
+
+
+/* Types of icsi sessions. Discovery sessions are used to query for what
+ * targets exist behin the portal connected to. Normal sessions are used to
+ * log in and do I/O to the SCSI LUNs
+ */
+enum iscsi_session_type {
+	ISCSI_SESSION_DISCOVERY = 1,
+	ISCSI_SESSION_NORMAL    = 2
+};
+
+/*
+ * Set the session type for a scsi context.
+ * Session type can only be set/changed while the iscsi context is not
+ * logged in to a target.
+ *
+ * Returns:
+ *  0: success
+ * <0: error
+ */
+int iscsi_set_session_type(struct iscsi_context *iscsi,
+			   enum iscsi_session_type session_type);
+
+
+/*
+ * Types of header digest we support. Default is NONE
+ */
+enum iscsi_header_digest {
+	ISCSI_HEADER_DIGEST_NONE        = 0,
+	ISCSI_HEADER_DIGEST_NONE_CRC32C = 1,
+	ISCSI_HEADER_DIGEST_CRC32C_NONE = 2,
+	ISCSI_HEADER_DIGEST_CRC32C      = 3
+};
+
+/*
+ * Set the desired header digest for a scsi context.
+ * Header digest can only be set/changed while the iscsi context is not
+ * logged in to a target.
+ *
+ * Returns:
+ *  0: success
+ * <0: error
+ */
+int iscsi_set_header_digest(struct iscsi_context *iscsi,
+			    enum iscsi_header_digest header_digest);
+
+
+/*
+ * check if the context is logged in or not
+ */
+int iscsi_is_logged_in(struct iscsi_context *iscsi);
+
+
+enum scsi_status {
+	SCSI_STATUS_GOOD            = 0,
+	SCSI_STATUS_CHECK_CONDITION = 2,
+	SCSI_STATUS_CANCELLED       = 0x0f000000,
+	SCSI_STATUS_ERROR           = 0x0f000001
+};
+
+
+/*
+ * Generic callback for completion of iscsi_*_async().
+ * command_data depends on status.
+ */
+typedef void (*iscsi_command_cb)(struct iscsi_context *iscsi, int status,
+				 void *command_data, void *private_data);
+
+
+
+/*
+ * Asynchronous call to connect a TCP connection to the target-host/port
+ *
+ * Returns:
+ *  0 if the call was initiated and a connection will be attempted. Result of
+ * the connection will be reported through the callback function.
+ * <0 if there was an error. The callback function will not be invoked.
+ *
+ * This command is unique in that the callback can be invoked twice.
+ *
+ * Callback parameters :
+ * status can be either of :
+ *    ISCSI_STATUS_GOOD     : Connection was successful. Command_data is NULL.
+ *                            In this case the callback will be invoked a
+ *                            second time once the connection is torn down.
+ *
+ *    ISCSI_STATUS_ERROR    : Either failed to establish the connection, or
+ *                            an already established connection has failed
+ *                            with an error.
+ *
+ * The callback will NOT be invoked if the session is explicitely torn down
+ * through a call to iscsi_disconnect() or iscsi_destroy_context().
+ */
+int iscsi_connect_async(struct iscsi_context *iscsi, const char *portal,
+			iscsi_command_cb cb, void *private_data);
+
+/*
+ * Synchronous call to connect a TCP connection to the target-host/port
+ *
+ * Returns:
+ *  0 if connected successfully.
+ * <0 if there was an error.
+ *
+ */
+int iscsi_connect_sync(struct iscsi_context *iscsi, const char *portal);
+
+
+/*
+ * Asynchronous call to connect a lun
+ * This function will connect to the portal, login, and verify that the lun
+ * is available.
+ *
+ * Returns:
+ *  0 if the call was initiated and a connection will be attempted. Result
+ *    of the connection will be reported through the callback function.
+ * <0 if there was an error. The callback function will not be invoked.
+ *
+ * This command is unique in that the callback can be invoked twice.
+ *
+ * Callback parameters :
+ * status can be either of :
+ *    ISCSI_STATUS_GOOD     : Connection was successful. Command_data is NULL.
+ *                            In this case the callback will be invoked a
+ *                            second time once the connection is torn down.
+ *
+ *    ISCSI_STATUS_ERROR    : Either failed to establish the connection, or
+ *                            an already established connection has failed
+ *                            with an error.
+ *
+ * The callback will NOT be invoked if the session is explicitely torn down
+ * through a call to iscsi_disconnect() or iscsi_destroy_context().
+ */
+int iscsi_full_connect_async(struct iscsi_context *iscsi, const char *portal,
+			     int lun, iscsi_command_cb cb, void *private_data);
+
+/*
+ * Synchronous call to connect a lun
+ * This function will connect to the portal, login, and verify that the lun
+ * is available.
+ *
+ * Returns:
+ *  0 if the cconnect was successful.
+ * <0 if there was an error.
+ */
+int iscsi_full_connect_sync(struct iscsi_context *iscsi, const char *portal,
+			    int lun);
+
+/*
+ * Disconnect a connection to a target.
+ * You can not disconnect while being logged in to a target.
+ *
+ * Returns:
+ *  0 disconnect was successful
+ * <0 error
+ */
+int iscsi_disconnect(struct iscsi_context *iscsi);
+
+/*
+ * Asynchronous call to perform an ISCSI login.
+ *
+ * Returns:
+ *  0 if the call was initiated and a login will be attempted. Result of the
+ *    login will be reported through the callback function.
+ * <0 if there was an error. The callback function will not be invoked.
+ *
+ * Callback parameters :
+ * status can be either of :
+ *    ISCSI_STATUS_GOOD     : login was successful. Command_data is always
+ *                            NULL.
+ *    ISCSI_STATUS_CANCELLED: login was aborted. Command_data is NULL.
+ *    ISCSI_STATUS_ERROR    : login failed. Command_data is NULL.
+ */
+int iscsi_login_async(struct iscsi_context *iscsi, iscsi_command_cb cb,
+		      void *private_data);
+
+/*
+ * Synchronous call to perform an ISCSI login.
+ *
+ * Returns:
+ *  0 if the login was successful
+ * <0 if there was an error.
+ */
+int iscsi_login_sync(struct iscsi_context *iscsi);
+
+
+/*
+ * Asynchronous call to perform an ISCSI logout.
+ *
+ * Returns:
+ *  0 if the call was initiated and a logout will be attempted. Result of the
+ *    logout will be reported through the callback function.
+ * <0 if there was an error. The callback function will not be invoked.
+ *
+ * Callback parameters :
+ * status can be either of :
+ *    ISCSI_STATUS_GOOD     : logout was successful. Command_data is always
+ *                            NULL.
+ *    ISCSI_STATUS_CANCELLED: logout was aborted. Command_data is NULL.
+ */
+int iscsi_logout_async(struct iscsi_context *iscsi, iscsi_command_cb cb,
+		       void *private_data);
+
+/*
+ * Synchronous call to perform an ISCSI logout.
+ *
+ * Returns:
+ *  0 if the logout was successful
+ * <0 if there was an error.
+ */
+int iscsi_logout_sync(struct iscsi_context *iscsi);
+
+
+/*
+ * Asynchronous call to perform an ISCSI discovery.
+ *
+ * discoveries can only be done on connected and logged in discovery sessions.
+ *
+ * Returns:
+ *  0 if the call was initiated and a discovery  will be attempted. Result
+ *    of the logout will be reported through the callback function.
+ * <0 if there was an error. The callback function will not be invoked.
+ *
+ * Callback parameters :
+ * status can be either of :
+ *    ISCSI_STATUS_GOOD     : Discovery was successful. Command_data is a
+ *                            pointer to a iscsi_discovery_address list of
+ *                            structures.
+ *                            This list of structures is only valid for the
+ *                            duration of the callback and all data will be
+ *                            freed once the callback returns.
+ *    ISCSI_STATUS_CANCELLED: Discovery was aborted. Command_data is NULL.
+ */
+int iscsi_discovery_async(struct iscsi_context *iscsi, iscsi_command_cb cb,
+			  void *private_data);
+
+struct iscsi_discovery_address {
+       struct iscsi_discovery_address *next;
+       const char *target_name;
+       const char *target_address;
+};
+
+/*
+ * Asynchronous call to perform an ISCSI NOP-OUT call
+ *
+ * Returns:
+ *  0 if the call was initiated and a nop-out will be attempted. Result will
+ *    be reported through the callback function.
+ * <0 if there was an error. The callback function will not be invoked.
+ *
+ * Callback parameters :
+ * status can be either of :
+ *    ISCSI_STATUS_GOOD     : NOP-OUT was successful and the server responded
+ *                            with a NOP-IN callback_data is a iscsi_data
+ *                            structure containing the data returned from
+ *                            the server.
+ *    ISCSI_STATUS_CANCELLED: Discovery was aborted. Command_data is NULL.
+ */
+int iscsi_nop_out_async(struct iscsi_context *iscsi, iscsi_command_cb cb,
+			unsigned char *data, int len, void *private_data);
+
+
+/* These are the possible status values for the callbacks for scsi commands.
+ * The content of command_data depends on the status type.
+ *
+ * status :
+ *   ISCSI_STATUS_GOOD the scsi command completed successfullt on the target.
+ *   If this scsi command returns DATA-IN, that data is stored in an scsi_task
+ *   structure returned in the command_data parameter. This buffer will be
+ *   automatically freed once the callback returns.
+ *
+ *   ISCSI_STATUS_CHECK_CONDITION the scsi command failed with a scsi sense.
+ *   Command_data contains a struct scsi_task. When the callback returns,
+ *   this buffer will automatically become freed.
+ *
+ *   ISCSI_STATUS_CANCELLED the scsi command was aborted. Command_data is
+ *   NULL.
+ *
+ *   ISCSI_STATUS_ERROR the command failed. Command_data is NULL.
+ */
+
+
+
+struct iscsi_data {
+       int size;
+       unsigned char *data;
+};
+
+
+/*
+ * Async commands for SCSI
+ */
+struct scsi_task;
+int iscsi_scsi_command_async(struct iscsi_context *iscsi, int lun,
+			     struct scsi_task *task, iscsi_command_cb cb,
+			     struct iscsi_data *data, void *private_data);
+
+int iscsi_reportluns_async(struct iscsi_context *iscsi, int report_type,
+			   int alloc_len, iscsi_command_cb cb,
+			   void *private_data);
+int iscsi_testunitready_async(struct iscsi_context *iscsi, int lun,
+			      iscsi_command_cb cb, void *private_data);
+int iscsi_inquiry_async(struct iscsi_context *iscsi, int lun, int evpd,
+			int page_code, int maxsize, iscsi_command_cb cb,
+			void *private_data);
+int iscsi_readcapacity10_async(struct iscsi_context *iscsi, int lun, int lba,
+			       int pmi, iscsi_command_cb cb,
+			       void *private_data);
+int iscsi_synchronizecache10_async(struct iscsi_context *iscsi, int lun,
+				   int lba, int num_blocks, int syncnv,
+				   int immed, iscsi_command_cb cb,
+				   void *private_data);
+
+int iscsi_read10_async(struct iscsi_context *iscsi, int lun, int lba,
+		       int datalen, int blocksize, iscsi_command_cb cb,
+		       void *private_data);
+int iscsi_write10_async(struct iscsi_context *iscsi, int lun,
+			unsigned char *data, int datalen, int lba, int fua,
+			int fuanv, int blocksize, iscsi_command_cb cb,
+			void *private_data);
+int iscsi_modesense6_async(struct iscsi_context *iscsi, int lun, int dbd,
+			   int pc, int page_code, int sub_page_code,
+			   unsigned char alloc_len, iscsi_command_cb cb,
+			   void *private_data);
+
+
+
+
+/*
+ * Sync commands for SCSI
+ */
+struct scsi_task *
+iscsi_scsi_command_sync(struct iscsi_context *iscsi, int lun,
+			struct scsi_task *task, struct iscsi_data *data);
+
+struct scsi_task *
+iscsi_reportluns_sync(struct iscsi_context *iscsi, int report_type,
+		      int alloc_len);
+
+struct scsi_task *
+iscsi_testunitready_sync(struct iscsi_context *iscsi, int lun);
+
+struct scsi_task *
+iscsi_inquiry_sync(struct iscsi_context *iscsi, int lun, int evpd,
+		   int page_code, int maxsize);
+
+struct scsi_task *
+iscsi_readcapacity10_sync(struct iscsi_context *iscsi, int lun, int lba,
+			  int pmi);
+
+struct scsi_task *
+iscsi_synchronizecache10_sync(struct iscsi_context *iscsi, int lun, int lba,
+			      int num_blocks, int syncnv, int immed);
diff --git a/block/iscsi/scsi-lowlevel.h b/block/iscsi/scsi-lowlevel.h
new file mode 100644
index 0000000..3778e13
--- /dev/null
+++ b/block/iscsi/scsi-lowlevel.h
@@ -0,0 +1,369 @@ 
+/*
+   Copyright (C) 2010 by Ronnie Sahlberg <ronniesahlberg@gmail.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.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, see <http://www.gnu.org/licenses/>.
+*/
+
+#define SCSI_CDB_MAX_SIZE			16
+
+enum scsi_opcode {
+	SCSI_OPCODE_TESTUNITREADY      = 0x00,
+	SCSI_OPCODE_INQUIRY            = 0x12,
+	SCSI_OPCODE_MODESENSE6         = 0x1a,
+	SCSI_OPCODE_READCAPACITY10     = 0x25,
+	SCSI_OPCODE_READ10             = 0x28,
+	SCSI_OPCODE_WRITE10            = 0x2A,
+	SCSI_OPCODE_SYNCHRONIZECACHE10 = 0x35,
+	SCSI_OPCODE_REPORTLUNS         = 0xA0
+};
+
+/* sense keys */
+enum scsi_sense_key {
+	SCSI_SENSE_NO_SENSE            = 0x00,
+	SCSI_SENSE_RECOVERED_ERROR     = 0x01,
+	SCSI_SENSE_NOT_READY           = 0x02,
+	SCSI_SENSE_MEDIUM_ERROR        = 0x03,
+	SCSI_SENSE_HARDWARE_ERROR      = 0x04,
+	SCSI_SENSE_ILLEGAL_REQUEST     = 0x05,
+	SCSI_SENSE_UNIT_ATTENTION      = 0x06,
+	SCSI_SENSE_DATA_PROTECTION     = 0x07,
+	SCSI_SENSE_BLANK_CHECK         = 0x08,
+	SCSI_SENSE_VENDOR_SPECIFIC     = 0x09,
+	SCSI_SENSE_COPY_ABORTED        = 0x0a,
+	SCSI_SENSE_COMMAND_ABORTED     = 0x0b,
+	SCSI_SENSE_OBSOLETE_ERROR_CODE = 0x0c,
+	SCSI_SENSE_OVERFLOW_COMMAND    = 0x0d,
+	SCSI_SENSE_MISCOMPARE          = 0x0e
+};
+
+const char *scsi_sense_key_str(int key);
+
+/* ascq */
+#define SCSI_SENSE_ASCQ_INVALID_FIELD_IN_CDB		0x2400
+#define SCSI_SENSE_ASCQ_LOGICAL_UNIT_NOT_SUPPORTED	0x2500
+#define SCSI_SENSE_ASCQ_BUS_RESET			0x2900
+
+const char *scsi_sense_ascq_str(int ascq);
+
+
+enum scsi_xfer_dir {
+	SCSI_XFER_NONE  = 0,
+	SCSI_XFER_READ  = 1,
+	SCSI_XFER_WRITE = 2
+};
+
+struct scsi_reportluns_params {
+	int report_type;
+};
+struct scsi_readcapacity10_params {
+	int lba;
+	int pmi;
+};
+struct scsi_inquiry_params {
+	int evpd;
+	int page_code;
+};
+struct scsi_modesense6_params {
+	int dbd;
+	int pc;
+	int page_code;
+	int sub_page_code;
+};
+
+struct scsi_sense {
+	unsigned char       error_type;
+	enum scsi_sense_key key;
+	int                 ascq;
+};
+
+struct scsi_data {
+	int            size;
+	unsigned char *data;
+};
+
+struct scsi_allocated_memory {
+	struct scsi_allocated_memory *next;
+	void                         *ptr;
+};
+
+struct scsi_task {
+	int status;
+
+	int cdb_size;
+	int xfer_dir;
+	int expxferlen;
+	unsigned char cdb[SCSI_CDB_MAX_SIZE];
+	union {
+		struct scsi_readcapacity10_params readcapacity10;
+		struct scsi_reportluns_params     reportluns;
+		struct scsi_inquiry_params        inquiry;
+		struct scsi_modesense6_params     modesense6;
+	} params;
+
+	struct scsi_sense sense;
+	struct scsi_data datain;
+	struct scsi_allocated_memory *mem;
+
+	void *ptr;
+};
+
+void scsi_free_scsi_task(struct scsi_task *task);
+void scsi_set_task_private_ptr(struct scsi_task *task, void *ptr);
+void *scsi_get_task_private_ptr(struct scsi_task *task);
+
+/*
+ * TESTUNITREADY
+ */
+struct scsi_task *scsi_cdb_testunitready(void);
+
+
+/*
+ * REPORTLUNS
+ */
+#define SCSI_REPORTLUNS_REPORT_ALL_LUNS				0x00
+#define SCSI_REPORTLUNS_REPORT_WELL_KNOWN_ONLY			0x01
+#define SCSI_REPORTLUNS_REPORT_AVAILABLE_LUNS_ONLY		0x02
+
+struct scsi_reportluns_list {
+	uint32_t num;
+	uint16_t luns[0];
+};
+
+struct scsi_task *scsi_reportluns_cdb(int report_type, int alloc_len);
+
+/*
+ * READCAPACITY10
+ */
+struct scsi_readcapacity10 {
+	uint32_t lba;
+	uint32_t block_size;
+};
+struct scsi_task *scsi_cdb_readcapacity10(int lba, int pmi);
+
+
+/*
+ * INQUIRY
+ */
+enum scsi_inquiry_peripheral_qualifier {
+	SCSI_INQUIRY_PERIPHERAL_QUALIFIER_CONNECTED     = 0x00,
+	SCSI_INQUIRY_PERIPHERAL_QUALIFIER_DISCONNECTED  = 0x01,
+	SCSI_INQUIRY_PERIPHERAL_QUALIFIER_NOT_SUPPORTED = 0x03
+};
+
+const char *scsi_devqualifier_to_str(
+			enum scsi_inquiry_peripheral_qualifier qualifier);
+
+enum scsi_inquiry_peripheral_device_type {
+	SCSI_INQUIRY_PERIPHERAL_DEVICE_TYPE_DIRECT_ACCESS            = 0x00,
+	SCSI_INQUIRY_PERIPHERAL_DEVICE_TYPE_SEQUENTIAL_ACCESS        = 0x01,
+	SCSI_INQUIRY_PERIPHERAL_DEVICE_TYPE_PRINTER                  = 0x02,
+	SCSI_INQUIRY_PERIPHERAL_DEVICE_TYPE_PROCESSOR                = 0x03,
+	SCSI_INQUIRY_PERIPHERAL_DEVICE_TYPE_WRITE_ONCE               = 0x04,
+	SCSI_INQUIRY_PERIPHERAL_DEVICE_TYPE_MMC                      = 0x05,
+	SCSI_INQUIRY_PERIPHERAL_DEVICE_TYPE_SCANNER                  = 0x06,
+	SCSI_INQUIRY_PERIPHERAL_DEVICE_TYPE_OPTICAL_MEMORY           = 0x07,
+	SCSI_INQUIRY_PERIPHERAL_DEVICE_TYPE_MEDIA_CHANGER            = 0x08,
+	SCSI_INQUIRY_PERIPHERAL_DEVICE_TYPE_COMMUNICATIONS           = 0x09,
+	SCSI_INQUIRY_PERIPHERAL_DEVICE_TYPE_STORAGE_ARRAY_CONTROLLER = 0x0c,
+	SCSI_INQUIRY_PERIPHERAL_DEVICE_TYPE_ENCLOSURE_SERVICES       = 0x0d,
+	SCSI_INQUIRY_PERIPHERAL_DEVICE_TYPE_SIMPLIFIED_DIRECT_ACCESS = 0x0e,
+	SCSI_INQUIRY_PERIPHERAL_DEVICE_TYPE_OPTICAL_CARD_READER      = 0x0f,
+	SCSI_INQUIRY_PERIPHERAL_DEVICE_TYPE_BRIDGE_CONTROLLER        = 0x10,
+	SCSI_INQUIRY_PERIPHERAL_DEVICE_TYPE_OSD                      = 0x11,
+	SCSI_INQUIRY_PERIPHERAL_DEVICE_TYPE_AUTOMATION               = 0x12,
+	SCSI_INQUIRY_PERIPHERAL_DEVICE_TYPE_SEQURITY_MANAGER         = 0x13,
+	SCSI_INQUIRY_PERIPHERAL_DEVICE_TYPE_WELL_KNOWN_LUN           = 0x1e,
+	SCSI_INQUIRY_PERIPHERAL_DEVICE_TYPE_UNKNOWN                  = 0x1f
+};
+
+const char *scsi_devtype_to_str(enum scsi_inquiry_peripheral_device_type type);
+
+enum scsi_version {
+	SCSI_VERSION_SPC  = 0x03,
+	SCSI_VERSION_SPC2 = 0x04,
+	SCSI_VERSION_SPC3 = 0x05
+};
+
+const char *scsi_version_to_str(enum scsi_version version);
+
+enum scsi_inquiry_tpgs {
+	SCSI_INQUIRY_TPGS_NO_SUPPORT            = 0x00,
+	SCSI_INQUIRY_TPGS_IMPLICIT              = 0x01,
+	SCSI_INQUIRY_TPGS_EXPLICIT              = 0x02,
+	SCSI_INQUIRY_TPGS_IMPLICIT_AND_EXPLICIT = 0x03
+};
+
+struct scsi_inquiry_standard {
+	enum scsi_inquiry_peripheral_qualifier periperal_qualifier;
+	enum scsi_inquiry_peripheral_device_type periperal_device_type;
+	int rmb;
+	int version;
+	int normaca;
+	int hisup;
+	int response_data_format;
+
+	int sccs;
+	int acc;
+	int tpgs;
+	int threepc;
+	int protect;
+
+	int encserv;
+	int multip;
+	int addr16;
+	int wbus16;
+	int sync;
+	int cmdque;
+
+	int clocking;
+	int qas;
+	int ius;
+
+	char vendor_identification[8+1];
+	char product_identification[16+1];
+	char product_revision_level[4+1];
+};
+
+enum scsi_inquiry_pagecode {
+	SCSI_INQUIRY_PAGECODE_SUPPORTED_VPD_PAGES          = 0x00,
+	SCSI_INQUIRY_PAGECODE_UNIT_SERIAL_NUMBER           = 0x80,
+	SCSI_INQUIRY_PAGECODE_DEVICE_IDENTIFICATION        = 0x83,
+	SCSI_INQUIRY_PAGECODE_BLOCK_DEVICE_CHARACTERISTICS = 0xB1
+};
+
+const char *scsi_inquiry_pagecode_to_str(int pagecode);
+
+struct scsi_inquiry_supported_pages {
+	enum scsi_inquiry_peripheral_qualifier periperal_qualifier;
+	enum scsi_inquiry_peripheral_device_type periperal_device_type;
+	enum scsi_inquiry_pagecode pagecode;
+
+	int num_pages;
+	unsigned char *pages;
+};
+
+struct scsi_inquiry_block_device_characteristics {
+	enum scsi_inquiry_peripheral_qualifier periperal_qualifier;
+	enum scsi_inquiry_peripheral_device_type periperal_device_type;
+	enum scsi_inquiry_pagecode pagecode;
+
+	int medium_rotation_rate;
+};
+
+struct scsi_task *scsi_cdb_inquiry(int evpd, int page_code, int alloc_len);
+
+struct scsi_inquiry_unit_serial_number {
+	enum scsi_inquiry_peripheral_qualifier periperal_qualifier;
+	enum scsi_inquiry_peripheral_device_type periperal_device_type;
+	enum scsi_inquiry_pagecode pagecode;
+
+	char *usn;
+};
+
+enum scsi_protocol_identifier {
+	SCSI_PROTOCOL_IDENTIFIER_FIBRE_CHANNEL = 0x00,
+	SCSI_PROTOCOL_IDENTIFIER_PARALLEL_SCSI = 0x01,
+	SCSI_PROTOCOL_IDENTIFIER_SSA           = 0x02,
+	SCSI_PROTOCOL_IDENTIFIER_IEEE_1394     = 0x03,
+	SCSI_PROTOCOL_IDENTIFIER_RDMA          = 0x04,
+	SCSI_PROTOCOL_IDENTIFIER_ISCSI         = 0x05,
+	SCSI_PROTOCOL_IDENTIFIER_SAS           = 0x06,
+	SCSI_PROTOCOL_IDENTIFIER_ADT           = 0x07,
+	SCSI_PROTOCOL_IDENTIFIER_ATA           = 0x08
+};
+
+const char *scsi_protocol_identifier_to_str(int identifier);
+
+enum scsi_codeset {
+	SCSI_CODESET_BINARY = 0x01,
+	SCSI_CODESET_ASCII  = 0x02,
+	SCSI_CODESET_UTF8   = 0x03
+};
+
+const char *scsi_codeset_to_str(int codeset);
+
+enum scsi_association {
+	SCSI_ASSOCIATION_LOGICAL_UNIT  = 0x00,
+	SCSI_ASSOCIATION_TARGET_PORT   = 0x01,
+	SCSI_ASSOCIATION_TARGET_DEVICE = 0x02
+};
+
+const char *scsi_association_to_str(int association);
+
+enum scsi_designator_type {
+	SCSI_DESIGNATOR_TYPE_VENDOR_SPECIFIC             = 0x00,
+	SCSI_DESIGNATOR_TYPE_T10_VENDORT_ID              = 0x01,
+	SCSI_DESIGNATOR_TYPE_EUI_64                      = 0x02,
+	SCSI_DESIGNATOR_TYPE_NAA                         = 0x03,
+	SCSI_DESIGNATOR_TYPE_RELATIVE_TARGET_PORT        = 0x04,
+	SCSI_DESIGNATOR_TYPE_TARGET_PORT_GROUP           = 0x05,
+	SCSI_DESIGNATOR_TYPE_LOGICAL_UNIT_GROUP          = 0x06,
+	SCSI_DESIGNATOR_TYPE_MD5_LOGICAL_UNIT_IDENTIFIER = 0x07,
+	SCSI_DESIGNATOR_TYPE_SCSI_NAME_STRING            = 0x08
+};
+
+const char *scsi_designator_type_to_str(int association);
+
+struct scsi_inquiry_device_designator {
+	struct scsi_inquiry_device_designator *next;
+
+	enum scsi_protocol_identifier protocol_identifier;
+	enum scsi_codeset code_set;
+	int piv;
+	enum scsi_association association;
+	enum scsi_designator_type designator_type;
+	int designator_length;
+	char *designator;
+};
+
+struct scsi_inquiry_device_identification {
+	enum scsi_inquiry_peripheral_qualifier periperal_qualifier;
+	enum scsi_inquiry_peripheral_device_type periperal_device_type;
+	enum scsi_inquiry_pagecode pagecode;
+
+	struct scsi_inquiry_device_designator *designators;
+};
+
+/*
+ * MODESENSE6
+ */
+enum scsi_modesense_page_control {
+	SCSI_MODESENSE_PC_CURRENT    = 0x00,
+	SCSI_MODESENSE_PC_CHANGEABLE = 0x01,
+	SCSI_MODESENSE_PC_DEFAULT    = 0x02,
+	SCSI_MODESENSE_PC_SAVED      = 0x03
+};
+
+enum scsi_modesense_page_code {
+	SCSI_MODESENSE_PAGECODE_RETURN_ALL_PAGES = 0x3f
+};
+
+struct scsi_task *scsi_cdb_modesense6(int dbd,
+			enum scsi_modesense_page_control pc,
+			enum scsi_modesense_page_code page_code,
+			int sub_page_code,
+			unsigned char alloc_len);
+
+
+
+
+int scsi_datain_getfullsize(struct scsi_task *task);
+void *scsi_datain_unmarshall(struct scsi_task *task);
+
+struct scsi_task *scsi_cdb_read10(int lba, int xferlen, int blocksize);
+struct scsi_task *scsi_cdb_write10(int lba, int xferlen, int fua, int fuanv,
+			int blocksize);
+
+struct scsi_task *scsi_cdb_synchronizecache10(int lba, int num_blocks,
+			int syncnv, int immed);
diff --git a/block/iscsi/slist.h b/block/iscsi/slist.h
new file mode 100644
index 0000000..0e9dc42
--- /dev/null
+++ b/block/iscsi/slist.h
@@ -0,0 +1,51 @@ 
+/*
+   Copyright (C) 2010 by Ronnie Sahlberg <ronniesahlberg@gmail.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.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, see <http://www.gnu.org/licenses/>.
+*/
+
+#define SLIST_ADD(list, item) \
+	do {							\
+		(item)->next = (*list);				\
+		(*list) = (item);				\
+	} while (0);
+
+#define SLIST_ADD_END(list, item)				\
+	if ((*list) == NULL) {	 				\
+	   SLIST_ADD((list), (item));				\
+	} else {						\
+	   void *head = (*list);				\
+	   while ((*list)->next)				\
+	     (*list) = (*list)->next;				\
+	   (*list)->next = (item);				\
+	   (item)->next = NULL;					\
+	   (*list) = head;					\
+	}
+
+#define SLIST_REMOVE(list, item) \
+	if ((*list) == (item)) { 				\
+	   (*list) = (item)->next;				\
+	} else {						\
+	   void *head = (*list);				\
+	   while ((*list)->next && (*list)->next != (item))     \
+	     (*list) = (*list)->next;				\
+	   if ((*list)->next != NULL) {		    	    	\
+	      (*list)->next = (*list)->next->next;		\
+	   }  		      					\
+	   (*list) = head;					\
+	}
+
+
+
+