Add SCSI transport attributes

From: 	Martin Hicks <mort@wildopensource.com>

Transport attributes are classes which can be
attached to by a scsi driver to export (and
later control) transport based properties.

drivers/scsi/Kconfig

@@ -196,6 +196,25 @@ config SCSI_LOGGING
 	  there should be no noticeable performance impact as long as you have
 	  logging turned off.
 
+menu "SCSI Transport Attributes"
+	depends on SCSI
+
+config SCSI_SPI_ATTRS
+	tristate "Parallel SCSI (SPI) Transport Attributes"
+	depends on SCSI
+	help
+	  If you wish to export transport-specific information about
+	  each attached SCSI device to sysfs, say Y.  Otherwise, say N.
+
+config SCSI_FC_ATTRS
+	tristate "FiberChannel Transport Attributes"
+	depends on SCSI
+	help
+	  If you wish to export transport-specific information about
+	  each attached FiberChannel device to sysfs, say Y.
+	  Otherwise, say N.
+
+endmenu
 
 menu "SCSI low-level drivers"
 	depends on SCSI!=n

drivers/scsi/Makefile

@@ -22,6 +22,14 @@ subdir-$(CONFIG_PCMCIA)		+= pcmcia
 
 obj-$(CONFIG_SCSI)		+= scsi_mod.o
 
+# --- NOTE ORDERING HERE ---
+# For kernel non-modular link, transport attributes need to
+# be initialised before drivers
+# --------------------------
+obj-$(CONFIG_SCSI_SPI_ATTRS)	+= scsi_transport_spi.o
+obj-$(CONFIG_SCSI_FC_ATTRS) 	+= scsi_transport_fc.o
+
+
 obj-$(CONFIG_SCSI_AMIGA7XX)	+= amiga7xx.o	53c7xx.o
 obj-$(CONFIG_A3000_SCSI)	+= a3000.o	wd33c93.o
 obj-$(CONFIG_A2091_SCSI)	+= a2091.o	wd33c93.o

drivers/scsi/hosts.c

@@ -32,6 +32,7 @@
 #include <linux/unistd.h>
 
 #include <scsi/scsi_host.h>
+#include <scsi/scsi_transport.h>
 #include "scsi.h"
 
 #include "scsi_priv.h"
@@ -222,6 +223,11 @@ struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *sht, int privsize)
 	shost->max_id = 8;
 	shost->max_lun = 8;
 
+	/* Give each shost a default transportt if the driver
+	 * doesn't yet support Transport Attributes */
+	if (!shost->transportt) 
+		shost->transportt = &blank_transport_template;
+
 	/*
 	 * All drivers right now should be able to handle 12 byte
 	 * commands.  Every so often there are requests for 16 byte

drivers/scsi/scsi_priv.h

@@ -156,6 +156,7 @@ extern int scsi_sysfs_add_sdev(struct scsi_device *);
 extern int scsi_sysfs_add_host(struct Scsi_Host *);
 extern int scsi_sysfs_register(void);
 extern void scsi_sysfs_unregister(void);
+extern struct scsi_transport_template blank_transport_template;
 
 extern struct class sdev_class;
 extern struct bus_type scsi_bus_type;

drivers/scsi/scsi_scan.c

@@ -35,6 +35,7 @@
 #include <scsi/scsi_driver.h>
 #include <scsi/scsi_devinfo.h>
 #include <scsi/scsi_host.h>
+#include <scsi/scsi_transport.h>
 #include "scsi.h"
 
 #include "scsi_priv.h"
@@ -192,7 +193,7 @@ static struct scsi_device *scsi_alloc_sdev(struct Scsi_Host *shost,
 	struct scsi_device *sdev, *device;
 	unsigned long flags;
 
-	sdev = kmalloc(sizeof(*sdev), GFP_ATOMIC);
+	sdev = kmalloc(sizeof(*sdev) + shost->transportt->size, GFP_ATOMIC);
 	if (!sdev)
 		goto out;
 
@@ -237,6 +238,11 @@ static struct scsi_device *scsi_alloc_sdev(struct Scsi_Host *shost,
 			goto out_free_queue;
 	}
 
+	if (shost->transportt->setup) {
+		if (shost->transportt->setup(sdev))
+			goto out_cleanup_slave;
+	}
+
 	if (get_device(&sdev->host->shost_gendev)) {
 
 		device_initialize(&sdev->sdev_gendev);
@@ -253,8 +259,15 @@ static struct scsi_device *scsi_alloc_sdev(struct Scsi_Host *shost,
 		snprintf(sdev->sdev_classdev.class_id, BUS_ID_SIZE,
 			 "%d:%d:%d:%d", sdev->host->host_no,
 			 sdev->channel, sdev->id, sdev->lun);
+
+		class_device_initialize(&sdev->transport_classdev);
+		sdev->transport_classdev.dev = &sdev->sdev_gendev;
+		sdev->transport_classdev.class = sdev->host->transportt->class;
+		snprintf(sdev->transport_classdev.class_id, BUS_ID_SIZE,
+			 "%d:%d:%d:%d", sdev->host->host_no,
+			 sdev->channel, sdev->id, sdev->lun);
 	} else
-		goto out_cleanup_slave;
+		goto out_cleanup_transport;
 
 	/*
 	 * If there are any same target siblings, add this to the
@@ -283,6 +296,9 @@ static struct scsi_device *scsi_alloc_sdev(struct Scsi_Host *shost,
 	spin_unlock_irqrestore(shost->host_lock, flags);
 	return sdev;
 
+out_cleanup_transport:
+	if (shost->transportt->cleanup)
+		shost->transportt->cleanup(sdev);
 out_cleanup_slave:
 	if (shost->hostt->slave_destroy)
 		shost->hostt->slave_destroy(sdev);
@@ -744,6 +760,8 @@ static int scsi_probe_and_add_lun(struct Scsi_Host *host,
 	} else {
 		if (sdev->host->hostt->slave_destroy)
 			sdev->host->hostt->slave_destroy(sdev);
+		if (sdev->host->transportt->cleanup)
+			sdev->host->transportt->cleanup(sdev);
 		put_device(&sdev->sdev_gendev);
 	}
  out:
@@ -1300,5 +1318,7 @@ void scsi_free_host_dev(struct scsi_device *sdev)
 
 	if (sdev->host->hostt->slave_destroy)
 		sdev->host->hostt->slave_destroy(sdev);
+	if (sdev->host->transportt->cleanup)
+		sdev->host->transportt->cleanup(sdev);
 	put_device(&sdev->sdev_gendev);
 }

drivers/scsi/scsi_sysfs.c

@@ -13,6 +13,7 @@
 #include <linux/device.h>
 
 #include <scsi/scsi_host.h>
+#include <scsi/scsi_transport.h>
 #include "scsi.h"
 
 #include "scsi_priv.h"
@@ -349,6 +350,7 @@ static int attr_add(struct device *dev, struct device_attribute *attr)
  **/
 int scsi_sysfs_add_sdev(struct scsi_device *sdev)
 {
+	struct class_device_attribute **attrs;
 	int error = -EINVAL, i;
 
 	if (sdev->sdev_state != SDEV_CREATED)
@@ -368,6 +370,12 @@ int scsi_sysfs_add_sdev(struct scsi_device *sdev)
 		goto clean_device;
 	}
 
+	if (sdev->transport_classdev.class) {
+		error = class_device_add(&sdev->transport_classdev);
+		if (error)
+			goto clean_device2;
+	}
+
 	get_device(&sdev->sdev_gendev);
 
 	if (sdev->host->hostt->sdev_attrs) {
@@ -393,10 +401,24 @@ int scsi_sysfs_add_sdev(struct scsi_device *sdev)
 		}
 	}
 
+ 	if (sdev->transport_classdev.class) {
+ 		attrs = sdev->host->transportt->attrs;
+ 		for (i = 0; attrs[i]; i++) {
+ 			error = class_device_create_file(&sdev->transport_classdev,
+ 							 attrs[i]);
+ 			if (error) {
+ 				scsi_remove_device(sdev);
+				goto out;
+			}
+ 		}
+ 	}
+
  out:
 	return error;
 
-clean_device:
+ clean_device2:
+	class_device_del(&sdev->sdev_classdev);
+ clean_device:
 	sdev->sdev_state = SDEV_CANCEL;
 
 	device_del(&sdev->sdev_gendev);
@@ -414,9 +436,12 @@ void scsi_remove_device(struct scsi_device *sdev)
 	if (sdev->sdev_state == SDEV_RUNNING || sdev->sdev_state == SDEV_CANCEL) {
 		sdev->sdev_state = SDEV_DEL;
 		class_device_unregister(&sdev->sdev_classdev);
+		class_device_unregister(&sdev->transport_classdev);
 		device_del(&sdev->sdev_gendev);
 		if (sdev->host->hostt->slave_destroy)
 			sdev->host->hostt->slave_destroy(sdev);
+		if (sdev->host->transportt->cleanup)
+			sdev->host->transportt->cleanup(sdev);
 		put_device(&sdev->sdev_gendev);
 	}
 }
@@ -503,3 +528,7 @@ int scsi_sysfs_add_host(struct Scsi_Host *shost)
 
 	return 0;
 }
+
+/* A blank transport template that is used in drivers that don't
+ * yet implement Transport Attributes */
+struct scsi_transport_template blank_transport_template = { 0, };

drivers/scsi/scsi_transport_fc.c

+/* 
+ *  FiberChannel transport specific attributes exported to sysfs.
+ *
+ *  Copyright (c) 2003 Silicon Graphics, Inc.  All rights reserved.
+ *
+ *  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/module.h>
+#include <linux/init.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_host.h>
+#include <scsi/scsi_transport.h>
+#include <scsi/scsi_transport_fc.h>
+
+static void transport_class_release(struct class_device *class_dev);
+
+struct class fc_transport_class = {
+	.name = "fc_transport",
+	.release = transport_class_release,
+};
+
+static __init int fc_transport_init(void)
+{
+	return class_register(&fc_transport_class);
+}
+
+static void __exit fc_transport_exit(void)
+{
+	class_unregister(&fc_transport_class);
+}
+
+static int fc_setup_transport_attrs(struct scsi_device *sdev)
+{
+	/* FIXME: Callback into the driver */
+	fc_node_name(sdev) = -1;
+	fc_port_name(sdev) = -1;
+	fc_port_id(sdev) = -1;
+
+	return 0;
+}
+
+static void transport_class_release(struct class_device *class_dev)
+{
+	struct scsi_device *sdev = transport_class_to_sdev(class_dev);
+	put_device(&sdev->sdev_gendev);
+}
+
+#define fc_transport_show_function(field, format_string, cast)			\
+static ssize_t									\
+show_fc_transport_##field (struct class_device *cdev, char *buf)		\
+{										\
+	struct scsi_device *sdev = transport_class_to_sdev(cdev);		\
+	struct fc_transport_attrs *tp;						\
+	tp = (struct fc_transport_attrs *)&sdev->transport_data;		\
+	return snprintf(buf, 20, format_string, cast tp->field);		\
+}
+
+#define fc_transport_rd_attr(field, format_string)				\
+	fc_transport_show_function(field, format_string, )			\
+static CLASS_DEVICE_ATTR( field, S_IRUGO, show_fc_transport_##field, NULL)
+
+#define fc_transport_rd_attr_cast(field, format_string, cast)			\
+	fc_transport_show_function(field, format_string, (cast))		\
+static CLASS_DEVICE_ATTR( field, S_IRUGO, show_fc_transport_##field, NULL)
+
+/* the FiberChannel Tranport Attributes: */
+fc_transport_rd_attr_cast(node_name, "0x%llx\n", unsigned long long);
+fc_transport_rd_attr_cast(port_name, "0x%llx\n", unsigned long long);
+fc_transport_rd_attr(port_id, "0x%06x\n");
+
+struct class_device_attribute *fc_transport_attrs[] = {
+	&class_device_attr_node_name,
+	&class_device_attr_port_name,
+	&class_device_attr_port_id,
+	NULL
+};
+
+struct scsi_transport_template fc_transport_template = {
+	.attrs = fc_transport_attrs,
+	.class = &fc_transport_class,
+	.setup = &fc_setup_transport_attrs,
+	.cleanup = NULL,
+	.size = sizeof(struct fc_transport_attrs) - sizeof(unsigned long),
+};
+EXPORT_SYMBOL(fc_transport_template);
+
+MODULE_AUTHOR("Martin Hicks");
+MODULE_DESCRIPTION("FC Transport Attributes");
+MODULE_LICENSE("GPL");
+
+module_init(fc_transport_init);
+module_exit(fc_transport_exit);

drivers/scsi/scsi_transport_spi.c

+/* 
+ *  Parallel SCSI (SPI) transport specific attributes exported to sysfs.
+ *
+ *  Copyright (c) 2003 Silicon Graphics, Inc.  All rights reserved.
+ *
+ *  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/module.h>
+#include <linux/init.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_host.h>
+#include <scsi/scsi_transport.h>
+#include <scsi/scsi_transport_spi.h>
+
+static void transport_class_release(struct class_device *class_dev);
+
+struct class spi_transport_class = {
+	.name = "spi_transport",
+	.release = transport_class_release,
+};
+
+static __init int spi_transport_init(void)
+{
+	return class_register(&spi_transport_class);
+}
+
+static void __exit spi_transport_exit(void)
+{
+	class_unregister(&spi_transport_class);
+}
+
+static int spi_setup_transport_attrs(struct scsi_device *sdev)
+{
+	/* FIXME: should callback into the driver to get these values */
+	spi_period(sdev) = -1;
+	spi_offset(sdev) = -1;
+
+	return 0;
+}
+
+static void transport_class_release(struct class_device *class_dev)
+{
+	struct scsi_device *sdev = transport_class_to_sdev(class_dev);
+	put_device(&sdev->sdev_gendev);
+}
+
+#define spi_transport_show_function(field, format_string)			\
+static ssize_t									\
+show_spi_transport_##field (struct class_device *cdev, char *buf)		\
+{										\
+	struct scsi_device *sdev = transport_class_to_sdev(cdev);		\
+	struct spi_transport_attrs *tp;						\
+	tp = (struct spi_transport_attrs *)&sdev->transport_data;		\
+	return snprintf(buf, 20, format_string, tp->field);			\
+}
+
+#define spi_transport_rd_attr(field, format_string)				\
+	spi_transport_show_function(field, format_string)			\
+static CLASS_DEVICE_ATTR( field, S_IRUGO, show_spi_transport_##field, NULL)
+
+/* The Parallel SCSI Tranport Attributes: */
+spi_transport_rd_attr(period, "%d\n");
+spi_transport_rd_attr(offset, "%d\n");
+
+struct class_device_attribute *spi_transport_attrs[] = {
+	&class_device_attr_period,
+	&class_device_attr_offset,
+	NULL
+};
+
+struct scsi_transport_template spi_transport_template = {
+	.attrs = spi_transport_attrs,
+	.class = &spi_transport_class,
+	.setup = &spi_setup_transport_attrs,
+	.cleanup = NULL,
+	.size = sizeof(struct spi_transport_attrs) - sizeof(unsigned long),
+};
+EXPORT_SYMBOL(spi_transport_template);
+
+MODULE_AUTHOR("Martin Hicks");
+MODULE_DESCRIPTION("SPI Transport Attributes");
+MODULE_LICENSE("GPL");
+
+module_init(spi_transport_init);
+module_exit(spi_transport_exit);

include/scsi/scsi_device.h

@@ -104,12 +104,17 @@ struct scsi_device {
 	struct device		sdev_gendev;
 	struct class_device	sdev_classdev;
 
+	struct class_device	transport_classdev;
+
 	enum scsi_device_state sdev_state;
-};
+	unsigned long		transport_data[0];
+} __attribute__((aligned(sizeof(unsigned long))));
 #define	to_scsi_device(d)	\
 	container_of(d, struct scsi_device, sdev_gendev)
 #define	class_to_sdev(d)	\
 	container_of(d, struct scsi_device, sdev_classdev)
+#define transport_class_to_sdev(class_dev) \
+	container_of(class_dev, struct scsi_device, transport_classdev)
 
 extern struct scsi_device *scsi_add_device(struct Scsi_Host *,
 		uint, uint, uint);

include/scsi/scsi_host.h

@@ -11,6 +11,7 @@ struct scsi_cmnd;
 struct scsi_device;
 struct Scsi_Host;
 struct scsi_host_cmd_pool;
+struct scsi_transport_template;
 
 
 /*
@@ -395,6 +396,7 @@ struct Scsi_Host {
 	unsigned int            eh_kill:1; /* set when killing the eh thread */
 	wait_queue_head_t       host_wait;
 	struct scsi_host_template *hostt;
+	struct scsi_transport_template *transportt;
 	volatile unsigned short host_busy;   /* commands actually active on low-level */
 	volatile unsigned short host_failed; /* commands that failed. */
     

include/scsi/scsi_transport.h

+/* 
+ *  Transport specific attributes.
+ *
+ *  Copyright (c) 2003 Silicon Graphics, Inc.  All rights reserved.
+ *
+ *  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_TRANSPORT_H
+#define SCSI_TRANSPORT_H
+
+struct scsi_transport_template {
+	/* The NULL terminated list of transport attributes
+	 * that should be exported.
+	 */
+	struct class_device_attribute **attrs;
+
+	/* The transport class that the device is in */
+	struct class *class;
+
+	/* Constructor/Destructor functions */
+	int (* setup)(struct scsi_device *);
+	void (* cleanup)(struct scsi_device *);
+	/* The size of the specific transport attribute structure (a
+	 * space of this size will be left at the end of the
+	 * scsi_device structure */
+	int	size;
+};
+
+#endif /* SCSI_TRANSPORT_H */

include/scsi/scsi_transport_fc.h

+/* 
+ *  FiberChannel transport specific attributes exported to sysfs.
+ *
+ *  Copyright (c) 2003 Silicon Graphics, Inc.  All rights reserved.
+ *
+ *  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_TRANSPORT_FC_H
+#define SCSI_TRANSPORT_FC_H
+
+struct scsi_transport_template;
+
+struct fc_transport_attrs {
+	int port_id;
+	uint64_t node_name;
+	uint64_t port_name;
+};
+
+/* accessor functions */
+#define fc_port_id(x)	(((struct fc_transport_attrs *)&(x)->transport_data)->port_id)
+#define fc_node_name(x)	(((struct fc_transport_attrs *)&(x)->transport_data)->node_name)
+#define fc_port_name(x)	(((struct fc_transport_attrs *)&(x)->transport_data)->port_name)
+
+extern struct scsi_transport_template fc_transport_template;
+
+#endif /* SCSI_TRANSPORT_FC_H */

include/scsi/scsi_transport_spi.h

+/* 
+ *  Parallel SCSI (SPI) transport specific attributes exported to sysfs.
+ *
+ *  Copyright (c) 2003 Silicon Graphics, Inc.  All rights reserved.
+ *
+ *  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_TRANSPORT_SPI_H
+#define SCSI_TRANSPORT_SPI_H
+
+#include <linux/config.h>
+
+struct scsi_transport_template;
+
+struct spi_transport_attrs {
+	int period;
+	int offset;
+};
+
+/* accessor functions */
+#define spi_period(x)	(((struct spi_transport_attrs *)&(x)->transport_data)->period)
+#define spi_offset(x)	(((struct spi_transport_attrs *)&(x)->transport_data)->offset)
+
+extern struct scsi_transport_template spi_transport_template;
+
+#endif /* SCSI_TRANSPORT_SPI_H */