[RFC 20/22] tcm: Add generic ProtoID and TransportID fabric handlers for SAS, FC, and iSCSI

From: Nicholas A. Bellinger
Date: Mon Aug 30 2010 - 05:23:16 EST


From: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx>

This patch adds a set of generic SAS, FC and iSCSI handlers into target_core_fabric_lib.c
that contain fabric dependent logic for ProtocolID (PIV) and TransportID processing
releated to >= SPC-3 persistent reservation SCSI Initiator and Target Port WWNs. These
generic handlers follow SPC-4 and are based on protocol dependent code in TCM_Loop, TCM_FC
and LIO-Target modules.

This a patch also allows TCM fabric modules to optionally support more than a single SCSI protcol
on a per fabric target endpoint (WWN+TPGT) context basis.

Signed-off-by: Nicholas A. Bellinger <nab@xxxxxxxxxxxxxxx>
---
drivers/target/target_core_fabric_lib.c | 452 +++++++++++++++++++++++++++++++
include/target/target_core_fabric_lib.h | 28 ++
2 files changed, 480 insertions(+), 0 deletions(-)
create mode 100644 drivers/target/target_core_fabric_lib.c
create mode 100644 include/target/target_core_fabric_lib.h

diff --git a/drivers/target/target_core_fabric_lib.c b/drivers/target/target_core_fabric_lib.c
new file mode 100644
index 0000000..b594b22
--- /dev/null
+++ b/drivers/target/target_core_fabric_lib.c
@@ -0,0 +1,452 @@
+/*******************************************************************************
+ * Filename: target_core_fabric_lib.c
+ *
+ * This file contains generic high level protocol identifier and PR
+ * handlers for TCM fabric modules
+ *
+ * Copyright (c) 2010 Rising Tide Systems, Inc.
+ * Copyright (c) 2010 Linux-iSCSI.org
+ *
+ * Nicholas A. Bellinger <nab@xxxxxxxxxxxxxxx>
+ *
+ * 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, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ ******************************************************************************/
+
+#include <linux/string.h>
+#include <linux/ctype.h>
+#include <linux/spinlock.h>
+#include <linux/smp_lock.h>
+#include <scsi/scsi.h>
+#include <scsi/scsi_cmnd.h>
+
+#include <target/target_core_base.h>
+#include <target/target_core_device.h>
+#include <target/target_core_transport.h>
+#include <target/target_core_fabric_ops.h>
+#include <target/target_core_configfs.h>
+
+#include "target_core_hba.h"
+#include "target_core_pr.h"
+
+/*
+ * Handlers for Serial Attached SCSI (SAS)
+ */
+u8 sas_get_fabric_proto_ident(struct se_portal_group *se_tpg)
+{
+ /*
+ * Return a SAS Serial SCSI Protocol identifier for loopback operations
+ * This is defined in section 7.5.1 Table 362 in spc4r17
+ */
+ return 0x6;
+}
+EXPORT_SYMBOL(sas_get_fabric_proto_ident);
+
+u32 sas_get_pr_transport_id(
+ struct se_portal_group *se_tpg,
+ struct se_node_acl *se_nacl,
+ struct t10_pr_registration *pr_reg,
+ int *format_code,
+ unsigned char *buf)
+{
+ unsigned char binary, *ptr;
+ int i;
+ u32 off = 4;
+ /*
+ * Set PROTOCOL IDENTIFIER to 6h for SAS
+ */
+ buf[0] = 0x06;
+ /*
+ * From spc4r17, 7.5.4.7 TransportID for initiator ports using SCSI
+ * over SAS Serial SCSI Protocol
+ */
+ ptr = &se_nacl->initiatorname[4]; /* Skip over 'naa. prefix */
+
+ for (i = 0; i < 16; i += 2) {
+ binary = transport_asciihex_to_binaryhex(&ptr[i]);
+ buf[off++] = binary;
+ }
+ /*
+ * The SAS Transport ID is a hardcoded 24-byte length
+ */
+ return 24;
+}
+EXPORT_SYMBOL(sas_get_pr_transport_id);
+
+u32 sas_get_pr_transport_id_len(
+ struct se_portal_group *se_tpg,
+ struct se_node_acl *se_nacl,
+ struct t10_pr_registration *pr_reg,
+ int *format_code)
+{
+ *format_code = 0;
+ /*
+ * From spc4r17, 7.5.4.7 TransportID for initiator ports using SCSI
+ * over SAS Serial SCSI Protocol
+ *
+ * The SAS Transport ID is a hardcoded 24-byte length
+ */
+ return 24;
+}
+EXPORT_SYMBOL(sas_get_pr_transport_id_len);
+
+/*
+ * Used for handling SCSI fabric dependent TransportIDs in SPC-3 and above
+ * Persistent Reservation SPEC_I_PT=1 and PROUT REGISTER_AND_MOVE operations.
+ */
+char *sas_parse_pr_out_transport_id(
+ struct se_portal_group *se_tpg,
+ const char *buf,
+ u32 *out_tid_len,
+ char **port_nexus_ptr)
+{
+ /*
+ * Assume the FORMAT CODE 00b from spc4r17, 7.5.4.7 TransportID
+ * for initiator ports using SCSI over SAS Serial SCSI Protocol
+ *
+ * The TransportID for a SAS Initiator Port is of fixed size of
+ * 24 bytes, and SAS does not contain a I_T nexus identifier,
+ * so we return the **port_nexus_ptr set to NULL.
+ */
+ *port_nexus_ptr = NULL;
+ *out_tid_len = 24;
+
+ return (char *)&buf[4];
+}
+EXPORT_SYMBOL(sas_parse_pr_out_transport_id);
+
+/*
+ * Handlers for Fibre Channel Protocol (FCP)
+ */
+u8 fc_get_fabric_proto_ident(struct se_portal_group *se_tpg)
+{
+ return 0x0; /* 0 = fcp-2 per SPC4 section 7.5.1 */
+}
+EXPORT_SYMBOL(fc_get_fabric_proto_ident);
+
+u32 fc_get_pr_transport_id_len(
+ struct se_portal_group *se_tpg,
+ struct se_node_acl *se_nacl,
+ struct t10_pr_registration *pr_reg,
+ int *format_code)
+{
+ *format_code = 0;
+ /*
+ * The FC Transport ID is a hardcoded 24-byte length
+ */
+ return 24;
+}
+EXPORT_SYMBOL(fc_get_pr_transport_id_len);
+
+u32 fc_get_pr_transport_id(
+ struct se_portal_group *se_tpg,
+ struct se_node_acl *se_nacl,
+ struct t10_pr_registration *pr_reg,
+ int *format_code,
+ unsigned char *buf)
+{
+ unsigned char binary, *ptr;
+ int i;
+ u32 off = 8;
+ /*
+ * PROTOCOL IDENTIFIER is 0h for FCP-2
+ *
+ * From spc4r17, 7.5.4.2 TransportID for initiator ports using
+ * SCSI over Fibre Channel
+ *
+ * We convert the ASCII formatted N Port name into a binary
+ * encoded TransportID.
+ */
+ ptr = &se_nacl->initiatorname[0];
+
+ for (i = 0; i < 24; ) {
+ if (!(strncmp(&ptr[i], ":", 1))) {
+ i++;
+ continue;
+ }
+ binary = transport_asciihex_to_binaryhex(&ptr[i]);
+ buf[off++] = binary;
+ i += 2;
+ }
+ /*
+ * The FC Transport ID is a hardcoded 24-byte length
+ */
+ return 24;
+}
+EXPORT_SYMBOL(fc_get_pr_transport_id);
+
+char *fc_parse_pr_out_transport_id(
+ struct se_portal_group *se_tpg,
+ const char *buf,
+ u32 *out_tid_len,
+ char **port_nexus_ptr)
+{
+ /*
+ * The TransportID for a FC N Port is of fixed size of
+ * 24 bytes, and FC does not contain a I_T nexus identifier,
+ * so we return the **port_nexus_ptr set to NULL.
+ */
+ *port_nexus_ptr = NULL;
+ *out_tid_len = 24;
+
+ return (char *)&buf[8];
+}
+EXPORT_SYMBOL(fc_parse_pr_out_transport_id);
+
+/*
+ * Handlers for Internet Small Computer Systems Interface (iSCSI)
+ */
+
+u8 iscsi_get_fabric_proto_ident(struct se_portal_group *se_tpg)
+{
+ /*
+ * This value is defined for "Internet SCSI (iSCSI)"
+ * in spc4r17 section 7.5.1 Table 362
+ */
+ return 0x5;
+}
+EXPORT_SYMBOL(iscsi_get_fabric_proto_ident);
+
+u32 iscsi_get_pr_transport_id(
+ struct se_portal_group *se_tpg,
+ struct se_node_acl *se_nacl,
+ struct t10_pr_registration *pr_reg,
+ int *format_code,
+ unsigned char *buf)
+{
+ u32 off = 4, padding = 0;
+ u16 len = 0;
+
+ spin_lock(&se_nacl->nacl_sess_lock);
+ /*
+ * Set PROTOCOL IDENTIFIER to 5h for iSCSI
+ */
+ buf[0] = 0x05;
+ /*
+ * From spc4r17 Section 7.5.4.6: TransportID for initiator
+ * ports using SCSI over iSCSI.
+ *
+ * The null-terminated, null-padded (see 4.4.2) ISCSI NAME field
+ * shall contain the iSCSI name of an iSCSI initiator node (see
+ * RFC 3720). The first ISCSI NAME field byte containing an ASCII
+ * null character terminates the ISCSI NAME field without regard for
+ * the specified length of the iSCSI TransportID or the contents of
+ * the ADDITIONAL LENGTH field.
+ */
+ len = sprintf(&buf[off], "%s", se_nacl->initiatorname);
+ /*
+ * Add Extra byte for NULL terminator
+ */
+ len++;
+ /*
+ * If there is ISID present with the registration and *format code == 1
+ * 1, use iSCSI Initiator port TransportID format.
+ *
+ * Otherwise use iSCSI Initiator device TransportID format that
+ * does not contain the ASCII encoded iSCSI Initiator iSID value
+ * provied by the iSCSi Initiator during the iSCSI login process.
+ */
+ if ((*format_code == 1) &&
+ (pr_reg->pr_reg_flags & PRF_ISID_PRESENT_AT_REG)) {
+ /*
+ * Set FORMAT CODE 01b for iSCSI Initiator port TransportID
+ * format.
+ */
+ buf[0] |= 0x40;
+ /*
+ * From spc4r17 Section 7.5.4.6: TransportID for initiator
+ * ports using SCSI over iSCSI. Table 390
+ *
+ * The SEPARATOR field shall contain the five ASCII
+ * characters ",i,0x".
+ *
+ * The null-terminated, null-padded ISCSI INITIATOR SESSION ID
+ * field shall contain the iSCSI initiator session identifier
+ * (see RFC 3720) in the form of ASCII characters that are the
+ * hexadecimal digits converted from the binary iSCSI initiator
+ * session identifier value. The first ISCSI INITIATOR SESSION
+ * ID field byte containing an ASCII null character
+ */
+ buf[off+len] = 0x2c; off++; /* ASCII Character: "," */
+ buf[off+len] = 0x69; off++; /* ASCII Character: "i" */
+ buf[off+len] = 0x2c; off++; /* ASCII Character: "," */
+ buf[off+len] = 0x30; off++; /* ASCII Character: "0" */
+ buf[off+len] = 0x78; off++; /* ASCII Character: "x" */
+ len += 5;
+ buf[off+len] = pr_reg->pr_reg_isid[0]; off++;
+ buf[off+len] = pr_reg->pr_reg_isid[1]; off++;
+ buf[off+len] = pr_reg->pr_reg_isid[2]; off++;
+ buf[off+len] = pr_reg->pr_reg_isid[3]; off++;
+ buf[off+len] = pr_reg->pr_reg_isid[4]; off++;
+ buf[off+len] = pr_reg->pr_reg_isid[5]; off++;
+ buf[off+len] = '\0'; off++;
+ len += 7;
+ }
+ spin_unlock(&se_nacl->nacl_sess_lock);
+ /*
+ * The ADDITIONAL LENGTH field specifies the number of bytes that follow
+ * in the TransportID. The additional length shall be at least 20 and
+ * shall be a multiple of four.
+ */
+ padding = ((-len) & 3);
+ if (padding != 0)
+ len += padding;
+
+ buf[2] = ((len >> 8) & 0xff);
+ buf[3] = (len & 0xff);
+ /*
+ * Increment value for total payload + header length for
+ * full status descriptor
+ */
+ len += 4;
+
+ return len;
+}
+EXPORT_SYMBOL(iscsi_get_pr_transport_id);
+
+u32 iscsi_get_pr_transport_id_len(
+ struct se_portal_group *se_tpg,
+ struct se_node_acl *se_nacl,
+ struct t10_pr_registration *pr_reg,
+ int *format_code)
+{
+ u32 len = 0, padding = 0;
+
+ spin_lock(&se_nacl->nacl_sess_lock);
+ len = strlen(se_nacl->initiatorname);
+ /*
+ * Add extra byte for NULL terminator
+ */
+ len++;
+ /*
+ * If there is ISID present with the registration, use format code:
+ * 01b: iSCSI Initiator port TransportID format
+ *
+ * If there is not an active iSCSI session, use format code:
+ * 00b: iSCSI Initiator device TransportID format
+ */
+ if (pr_reg->pr_reg_flags & PRF_ISID_PRESENT_AT_REG) {
+ len += 5; /* For ",i,0x" ASCII seperator */
+ len += 7; /* For iSCSI Initiator Session ID + Null terminator */
+ *format_code = 1;
+ } else
+ *format_code = 0;
+ spin_unlock(&se_nacl->nacl_sess_lock);
+ /*
+ * The ADDITIONAL LENGTH field specifies the number of bytes that follow
+ * in the TransportID. The additional length shall be at least 20 and
+ * shall be a multiple of four.
+ */
+ padding = ((-len) & 3);
+ if (padding != 0)
+ len += padding;
+ /*
+ * Increment value for total payload + header length for
+ * full status descriptor
+ */
+ len += 4;
+
+ return len;
+}
+EXPORT_SYMBOL(iscsi_get_pr_transport_id_len);
+
+char *iscsi_parse_pr_out_transport_id(
+ struct se_portal_group *se_tpg,
+ const char *buf,
+ u32 *out_tid_len,
+ char **port_nexus_ptr)
+{
+ char *p;
+ u32 tid_len, padding;
+ int i;
+ u16 add_len;
+ u8 format_code = (buf[0] & 0xc0);
+ /*
+ * Check for FORMAT CODE 00b or 01b from spc4r17, section 7.5.4.6:
+ *
+ * TransportID for initiator ports using SCSI over iSCSI,
+ * from Table 388 -- iSCSI TransportID formats.
+ *
+ * 00b Initiator port is identified using the world wide unique
+ * SCSI device name of the iSCSI initiator
+ * device containing the initiator port (see table 389).
+ * 01b Initiator port is identified using the world wide unique
+ * initiator port identifier (see table 390).10b to 11b
+ * Reserved
+ */
+ if ((format_code != 0x00) && (format_code != 0x40)) {
+ printk(KERN_ERR "Illegal format code: 0x%02x for iSCSI"
+ " Initiator Transport ID\n", format_code);
+ return NULL;
+ }
+ /*
+ * If the caller wants the TransportID Length, we set that value for the
+ * entire iSCSI Tarnsport ID now.
+ */
+ if (out_tid_len != NULL) {
+ add_len = ((buf[2] >> 8) & 0xff);
+ add_len |= (buf[3] & 0xff);
+
+ tid_len = strlen((char *)&buf[4]);
+ tid_len += 4; /* Add four bytes for iSCSI Transport ID header */
+ tid_len += 1; /* Add one byte for NULL terminator */
+ padding = ((-tid_len) & 3);
+ if (padding != 0)
+ tid_len += padding;
+
+ if ((add_len + 4) != tid_len) {
+ printk(KERN_INFO "LIO-Target Extracted add_len: %hu "
+ "does not match calculated tid_len: %u,"
+ " using tid_len instead\n", add_len+4, tid_len);
+ *out_tid_len = tid_len;
+ } else
+ *out_tid_len = (add_len + 4);
+ }
+ /*
+ * Check for ',i,0x' seperator between iSCSI Name and iSCSI Initiator
+ * Session ID as defined in Table 390 - iSCSI initiator port TransportID
+ * format.
+ */
+ if (format_code == 0x40) {
+ p = strstr((char *)&buf[4], ",i,0x");
+ if (!(p)) {
+ printk(KERN_ERR "Unable to locate \",i,0x\" seperator"
+ " for Initiator port identifier: %s\n",
+ (char *)&buf[4]);
+ return NULL;
+ }
+ *p = '\0'; /* Terminate iSCSI Name */
+ p += 5; /* Skip over ",i,0x" seperator */
+
+ *port_nexus_ptr = p;
+ /*
+ * Go ahead and do the lower case conversion of the received
+ * 12 ASCII characters representing the ISID in the TransportID
+ * for comparision against the running iSCSI session's ISID from
+ * iscsi_target.c:lio_sess_get_initiator_sid()
+ */
+ for (i = 0; i < 12; i++) {
+ if (isdigit(*p)) {
+ p++;
+ continue;
+ }
+ *p = tolower(*p);
+ p++;
+ }
+ }
+
+ return (char *)&buf[4];
+}
+EXPORT_SYMBOL(iscsi_parse_pr_out_transport_id);
diff --git a/include/target/target_core_fabric_lib.h b/include/target/target_core_fabric_lib.h
new file mode 100644
index 0000000..c2f8d0e
--- /dev/null
+++ b/include/target/target_core_fabric_lib.h
@@ -0,0 +1,28 @@
+#ifndef TARGET_CORE_FABRIC_LIB_H
+#define TARGET_CORE_FABRIC_LIB_H
+
+extern u8 sas_get_fabric_proto_ident(struct se_portal_group *);
+extern u32 sas_get_pr_transport_id(struct se_portal_group *, struct se_node_acl *,
+ struct t10_pr_registration *, int *, unsigned char *);
+extern u32 sas_get_pr_transport_id_len(struct se_portal_group *, struct se_node_acl *,
+ struct t10_pr_registration *, int *);
+extern char *sas_parse_pr_out_transport_id(struct se_portal_group *,
+ const char *, u32 *, char **);
+
+extern u8 fc_get_fabric_proto_ident(struct se_portal_group *);
+extern u32 fc_get_pr_transport_id(struct se_portal_group *, struct se_node_acl *,
+ struct t10_pr_registration *, int *, unsigned char *);
+extern u32 fc_get_pr_transport_id_len(struct se_portal_group *, struct se_node_acl *,
+ struct t10_pr_registration *, int *);
+extern char *fc_parse_pr_out_transport_id(struct se_portal_group *,
+ const char *, u32 *, char **);
+
+extern u8 iscsi_get_fabric_proto_ident(struct se_portal_group *);
+extern u32 iscsi_get_pr_transport_id(struct se_portal_group *, struct se_node_acl *,
+ struct t10_pr_registration *, int *, unsigned char *);
+extern u32 iscsi_get_pr_transport_id_len(struct se_portal_group *, struct se_node_acl *,
+ struct t10_pr_registration *, int *);
+extern char *iscsi_parse_pr_out_transport_id(struct se_portal_group *,
+ const char *, u32 *, char **);
+
+#endif /* TARGET_CORE_FABRIC_LIB_H */
--
1.7.2.2

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