[SCSI] iscsi class: add bsg support to iscsi class

This patch adds bsg support to the iscsi class. There is only
1 request, the host vendor one, supported. It is expected that
this would be used for things like flash updates.

This patch is made over this one
http://marc.info/?l=linux-scsi&m=131149780020992&w=2

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

2 files changed, 116 insertions, 1 deletions

diff --git a/include/scsi/scsi_bsg_iscsi.h b/include/scsi/scsi_bsg_iscsi.h
new file mode 100644
index 000000000000..fd5689d4c052
--- /dev/null
+++ b/include/scsi/scsi_bsg_iscsi.h
@@ -0,0 +1,110 @@
+/*
+ *  iSCSI Transport BSG Interface
+ *
+ *  Copyright (C) 2009   James Smart, Emulex Corporation
+ *
+ *  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
+ *
+ */
+
+#ifndef SCSI_BSG_ISCSI_H
+#define SCSI_BSG_ISCSI_H
+
+/*
+ * This file intended to be included by both kernel and user space
+ */
+
+#include <scsi/scsi.h>
+
+/*
+ * iSCSI Transport SGIO v4 BSG Message Support
+ */
+
+/* Default BSG request timeout (in seconds) */
+#define ISCSI_DEFAULT_BSG_TIMEOUT      (10 * HZ)
+
+
+/*
+ * Request Message Codes supported by the iSCSI Transport
+ */
+
+/* define the class masks for the message codes */
+#define ISCSI_BSG_CLS_MASK     0xF0000000      /* find object class */
+#define ISCSI_BSG_HST_MASK     0x80000000      /* iscsi host class */
+
+/* iscsi host Message Codes */
+#define ISCSI_BSG_HST_VENDOR           (ISCSI_BSG_HST_MASK | 0x000000FF)
+
+
+/*
+ * iSCSI Host Messages
+ */
+
+/* ISCSI_BSG_HST_VENDOR : */
+
+/* Request:
+ * Note: When specifying vendor_id, be sure to read the Vendor Type and ID
+ *   formatting requirements specified in scsi_netlink.h
+ */
+struct iscsi_bsg_host_vendor {
+	/*
+	 * Identifies the vendor that the message is formatted for. This
+	 * should be the recipient of the message.
+	 */
+	uint64_t vendor_id;
+
+	/* start of vendor command area */
+	uint32_t vendor_cmd[0];
+};
+
+/* Response:
+ */
+struct iscsi_bsg_host_vendor_reply {
+	/* start of vendor response area */
+	uint32_t vendor_rsp[0];
+};
+
+
+/* request (CDB) structure of the sg_io_v4 */
+struct iscsi_bsg_request {
+	uint32_t msgcode;
+	union {
+		struct iscsi_bsg_host_vendor    h_vendor;
+	} rqst_data;
+} __attribute__((packed));
+
+
+/* response (request sense data) structure of the sg_io_v4 */
+struct iscsi_bsg_reply {
+	/*
+	 * The completion result. Result exists in two forms:
+	 * if negative, it is an -Exxx system errno value. There will
+	 * be no further reply information supplied.
+	 * else, it's the 4-byte scsi error result, with driver, host,
+	 * msg and status fields. The per-msgcode reply structure
+	 * will contain valid data.
+	 */
+	uint32_t result;
+
+	/* If there was reply_payload, how much was recevied ? */
+	uint32_t reply_payload_rcv_len;
+
+	union {
+		struct iscsi_bsg_host_vendor_reply      vendor_reply;
+	} reply_data;
+};
+
+
+#endif /* SCSI_BSG_ISCSI_H */
diff --git a/include/scsi/scsi_transport_iscsi.h b/include/scsi/scsi_transport_iscsi.h
index 77e6dd60fb4b..4a3edeeae8f6 100644
--- a/include/scsi/scsi_transport_iscsi.h
+++ b/include/scsi/scsi_transport_iscsi.h
@@ -38,6 +38,7 @@ struct iscsi_conn;
 struct iscsi_task;
 struct sockaddr;
 struct iscsi_iface;
+struct bsg_job;
 
 /**
  * struct iscsi_transport - iSCSI Transport template
@@ -141,9 +142,9 @@ struct iscsi_transport {
 				enum iscsi_param_type param_type,
 				int param, char *buf);
 	mode_t (*attr_is_visible)(int param_type, int param);
+	int (*bsg_request)(struct bsg_job *job);
 };
 
-
 /*
  * transport registration upcalls
  */
@@ -227,8 +228,12 @@ struct iscsi_cls_session {
 struct iscsi_cls_host {
 	atomic_t nr_scans;
 	struct mutex mutex;
+	struct request_queue *bsg_q;
 };
 
+#define iscsi_job_to_shost(_job) \
+        dev_to_shost(_job->dev)
+
 extern void iscsi_host_for_each_session(struct Scsi_Host *shost,
 				void (*fn)(struct iscsi_cls_session *));