Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-post-merge-2.6

>>>>>>>>>> The TCM v4 fabric module script generator <<<<<<<<<<

Greetings all,

This document is intended to be a mini-HOWTO for using the tcm_mod_builder.py

script to generate a brand new functional TCM v4 fabric .ko module of your very own,

that once built can be immediately be loaded to start access the new TCM/ConfigFS

fabric skeleton, by simply using:

	modprobe $TCM_NEW_MOD

	mkdir -p /sys/kernel/config/target/$TCM_NEW_MOD

This script will create a new drivers/target/$TCM_NEW_MOD/, and will do the following

	*) Generate new API callers for drivers/target/target_core_fabric_configs.c logic

	   ->make_nodeacl(), ->drop_nodeacl(), ->make_tpg(), ->drop_tpg()

	   ->make_wwn(), ->drop_wwn().  These are created into $TCM_NEW_MOD/$TCM_NEW_MOD_configfs.c

	*) Generate basic infrastructure for loading/unloading LKMs and TCM/ConfigFS fabric module

	   using a skeleton struct target_core_fabric_ops API template.

	*) Based on user defined T10 Proto_Ident for the new fabric module being built,

	   the TransportID / Initiator and Target WWPN related handlers for

	   SPC-3 persistent reservation are automatically generated in $TCM_NEW_MOD/$TCM_NEW_MOD_fabric.c

	   using drivers/target/target_core_fabric_lib.c logic.

	*) NOP API calls for all other Data I/O path and fabric dependent attribute logic

	   in $TCM_NEW_MOD/$TCM_NEW_MOD_fabric.c

tcm_mod_builder.py depends upon the mandatory '-p $PROTO_IDENT' and '-m

$FABRIC_MOD_name' parameters, and actually running the script looks like:

target:/mnt/sdb/lio-core-2.6.git/Documentation/target# python tcm_mod_builder.py -p iSCSI -m tcm_nab5000

tcm_dir: /mnt/sdb/lio-core-2.6.git/Documentation/target/../../

Set fabric_mod_name: tcm_nab5000

Set fabric_mod_dir:

/mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000

Using proto_ident: iSCSI

Creating fabric_mod_dir:

/mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000

Writing file:

/mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000/tcm_nab5000_base.h

Using tcm_mod_scan_fabric_ops:

/mnt/sdb/lio-core-2.6.git/Documentation/target/../../include/target/target_core_fabric_ops.h

Writing file:

/mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000/tcm_nab5000_fabric.c

Writing file:

/mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000/tcm_nab5000_fabric.h

Writing file:

/mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000/tcm_nab5000_configfs.c

Writing file:

/mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000/Kbuild

Writing file:

/mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000/Kconfig

Would you like to add tcm_nab5000to drivers/target/Kbuild..? [yes,no]: yes

Would you like to add tcm_nab5000to drivers/target/Kconfig..? [yes,no]: yes

At the end of tcm_mod_builder.py. the script will ask to add the following

line to drivers/target/Kbuild:

	obj-$(CONFIG_TCM_NAB5000)       += tcm_nab5000/

and the same for drivers/target/Kconfig:

	source "drivers/target/tcm_nab5000/Kconfig"

*) Run 'make menuconfig' and select the new CONFIG_TCM_NAB5000 item:

	<M>   TCM_NAB5000 fabric module

*) Build using 'make modules', once completed you will have:

target:/mnt/sdb/lio-core-2.6.git# ls -la drivers/target/tcm_nab5000/

total 1348

drwxr-xr-x 2 root root   4096 2010-10-05 03:23 .

drwxr-xr-x 9 root root   4096 2010-10-05 03:22 ..

-rw-r--r-- 1 root root    282 2010-10-05 03:22 Kbuild

-rw-r--r-- 1 root root    171 2010-10-05 03:22 Kconfig

-rw-r--r-- 1 root root     49 2010-10-05 03:23 modules.order

-rw-r--r-- 1 root root    738 2010-10-05 03:22 tcm_nab5000_base.h

-rw-r--r-- 1 root root   9096 2010-10-05 03:22 tcm_nab5000_configfs.c

-rw-r--r-- 1 root root 191200 2010-10-05 03:23 tcm_nab5000_configfs.o

-rw-r--r-- 1 root root  40504 2010-10-05 03:23 .tcm_nab5000_configfs.o.cmd

-rw-r--r-- 1 root root   5414 2010-10-05 03:22 tcm_nab5000_fabric.c

-rw-r--r-- 1 root root   2016 2010-10-05 03:22 tcm_nab5000_fabric.h

-rw-r--r-- 1 root root 190932 2010-10-05 03:23 tcm_nab5000_fabric.o

-rw-r--r-- 1 root root  40713 2010-10-05 03:23 .tcm_nab5000_fabric.o.cmd

-rw-r--r-- 1 root root 401861 2010-10-05 03:23 tcm_nab5000.ko

-rw-r--r-- 1 root root    265 2010-10-05 03:23 .tcm_nab5000.ko.cmd

-rw-r--r-- 1 root root    459 2010-10-05 03:23 tcm_nab5000.mod.c

-rw-r--r-- 1 root root  23896 2010-10-05 03:23 tcm_nab5000.mod.o

-rw-r--r-- 1 root root  22655 2010-10-05 03:23 .tcm_nab5000.mod.o.cmd

-rw-r--r-- 1 root root 379022 2010-10-05 03:23 tcm_nab5000.o

-rw-r--r-- 1 root root    211 2010-10-05 03:23 .tcm_nab5000.o.cmd

*) Load the new module, create a lun_0 configfs group, and add new TCM Core

   IBLOCK backstore symlink to port:

target:/mnt/sdb/lio-core-2.6.git# insmod drivers/target/tcm_nab5000.ko

target:/mnt/sdb/lio-core-2.6.git# mkdir -p /sys/kernel/config/target/nab5000/iqn.foo/tpgt_1/lun/lun_0

target:/mnt/sdb/lio-core-2.6.git# cd /sys/kernel/config/target/nab5000/iqn.foo/tpgt_1/lun/lun_0/

target:/sys/kernel/config/target/nab5000/iqn.foo/tpgt_1/lun/lun_0# ln -s /sys/kernel/config/target/core/iblock_0/lvm_test0 nab5000_port

target:/sys/kernel/config/target/nab5000/iqn.foo/tpgt_1/lun/lun_0# cd -

target:/mnt/sdb/lio-core-2.6.git# tree /sys/kernel/config/target/nab5000/

/sys/kernel/config/target/nab5000/

|-- discovery_auth

|-- iqn.foo

|   `-- tpgt_1

|       |-- acls

|       |-- attrib

|       |-- lun

|       |   `-- lun_0

|       |       |-- alua_tg_pt_gp

|       |       |-- alua_tg_pt_offline

|       |       |-- alua_tg_pt_status

|       |       |-- alua_tg_pt_write_md

|	|	`-- nab5000_port -> ../../../../../../target/core/iblock_0/lvm_test0

|       |-- np

|       `-- param

`-- version

target:/mnt/sdb/lio-core-2.6.git# lsmod

Module                  Size  Used by

tcm_nab5000             3935  4

iscsi_target_mod      193211  0

target_core_stgt        8090  0

target_core_pscsi      11122  1

target_core_file        9172  2

target_core_iblock      9280  1

target_core_mod       228575  31

tcm_nab5000,iscsi_target_mod,target_core_stgt,target_core_pscsi,target_core_file,target_core_iblock

libfc                  73681  0

scsi_debug             56265  0

scsi_tgt                8666  1 target_core_stgt

configfs               20644  2 target_core_mod

----------------------------------------------------------------------

Future TODO items:

	*) Add more T10 proto_idents

	*) Make tcm_mod_dump_fabric_ops() smarter and generate function pointer

	   defs directly from include/target/target_core_fabric_ops.h:struct target_core_fabric_ops

	   structure members.

October 5th, 2010

Nicholas A. Bellinger <nab@linux-iscsi.org>

source "drivers/md/Kconfig"

source "drivers/target/Kconfig"

source "drivers/message/fusion/Kconfig"

source "drivers/firewire/Kconfig"

obj-$(CONFIG_IDE)		+= ide/

obj-$(CONFIG_SCSI)		+= scsi/

obj-$(CONFIG_ATA)		+= ata/

obj-$(CONFIG_TARGET_CORE)	+= target/

obj-$(CONFIG_MTD)		+= mtd/

obj-$(CONFIG_SPI)		+= spi/

obj-y				+= net/

static void set_media_not_present(struct scsi_disk *sdkp)

{

	if (sdkp->media_present)

		sdkp->device->changed = 1;

	if (sdkp->device->removable) {

		sdkp->media_present = 0;

		sdkp->capacity = 0;

	sdkp->device->changed = 1;

	}

}

static int media_not_present(struct scsi_disk *sdkp,

			     struct scsi_sense_hdr *sshdr)

{

	if (!scsi_sense_valid(sshdr))

		return 0;

	/* not invoked for commands that could return deferred errors */

	switch (sshdr->sense_key) {

	case UNIT_ATTENTION:

	case NOT_READY:

		/* medium not present */

		if (sshdr->asc == 0x3A) {

			set_media_not_present(sdkp);

			return 1;

		}

	}

	return 0;

}

/**

 *	sd_media_changed - check if our medium changed

 *	sd_check_events - check media events

 *	@disk: kernel device descriptor

 *	@clearing: disk events currently being cleared

 *

 *	Returns 0 if not applicable or no change; 1 if change

 *	Returns mask of DISK_EVENT_*.

 *

 *	Note: this function is invoked from the block subsystem.

 **/

static int sd_media_changed(struct gendisk *disk)

static unsigned int sd_check_events(struct gendisk *disk, unsigned int clearing)

{

	struct scsi_disk *sdkp = scsi_disk(disk);

	struct scsi_device *sdp = sdkp->device;

	struct scsi_sense_hdr *sshdr = NULL;

	int retval;

	SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_media_changed\n"));

	if (!sdp->removable)

		return 0;

	SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_check_events\n"));

	/*

	 * If the device is offline, don't send any commands - just pretend as

					      sshdr);

	}

	if (retval) {

	/* failed to execute TUR, assume media not present */

	if (host_byte(retval)) {

		set_media_not_present(sdkp);

		goto out;

	}

	if (media_not_present(sdkp, sshdr))

		goto out;

	/*

	 * For removable scsi disk we have to recognise the presence

	 * of a disk in the drive. This is kept in the struct scsi_disk

	 * struct and tested at open !  Daniel Roche (dan@lectra.fr)

	 * of a disk in the drive.

	 */

	if (!sdkp->media_present)

		sdp->changed = 1;

	sdkp->media_present = 1;

out:

	/*

	 * Report a media change under the following conditions:

	 *

	 *	Medium is present now and wasn't present before.

	 *	Medium wasn't present before and is present now.

	 *	Medium was present at all times, but it changed while

	 *		we weren't looking (sdp->changed is set).

	 * sdp->changed is set under the following conditions:

	 *

	 * If there was no medium before and there is no medium now then

	 * don't report a change, even if a medium was inserted and removed

	 * while we weren't looking.

	 *	Medium present state has changed in either direction.

	 *	Device has indicated UNIT_ATTENTION.

	 */

	retval = (sdkp->media_present != sdkp->previous_state ||

			(sdkp->media_present && sdp->changed));

	if (retval)

		sdev_evt_send_simple(sdp, SDEV_EVT_MEDIA_CHANGE, GFP_KERNEL);

	sdkp->previous_state = sdkp->media_present;

	/* sdp->changed indicates medium was changed or is not present */

	sdp->changed = !sdkp->media_present;

	kfree(sshdr);

	retval = sdp->changed ? DISK_EVENT_MEDIA_CHANGE : 0;

	sdp->changed = 0;

	return retval;

}

#ifdef CONFIG_COMPAT

	.compat_ioctl		= sd_compat_ioctl,

#endif

	.media_changed		= sd_media_changed,

	.check_events		= sd_check_events,

	.revalidate_disk	= sd_revalidate_disk,

	.unlock_native_capacity	= sd_unlock_native_capacity,

};

	return good_bytes;

}

static int media_not_present(struct scsi_disk *sdkp,

			     struct scsi_sense_hdr *sshdr)

{

	if (!scsi_sense_valid(sshdr))

		return 0;

	/* not invoked for commands that could return deferred errors */

	if (sshdr->sense_key != NOT_READY &&

	    sshdr->sense_key != UNIT_ATTENTION)

		return 0;

	if (sshdr->asc != 0x3A) /* medium not present */

		return 0;

	set_media_not_present(sdkp);

	return 1;

}

/*

 * spinup disk - called only in sd_revalidate_disk()

 */

	 */

	if (sdp->removable &&

	    sense_valid && sshdr->sense_key == NOT_READY)

		sdp->changed = 1;

		set_media_not_present(sdkp);

	/*

	 * We used to set media_present to 0 here to indicate no media

	gd->driverfs_dev = &sdp->sdev_gendev;

	gd->flags = GENHD_FL_EXT_DEVT;

	if (sdp->removable)

	if (sdp->removable) {

		gd->flags |= GENHD_FL_REMOVABLE;

		gd->events |= DISK_EVENT_MEDIA_CHANGE;

	}

	add_disk(gd);

	sd_dif_config_host(sdkp);

	sdkp->disk = gd;

	sdkp->index = index;

	atomic_set(&sdkp->openers, 0);

	sdkp->previous_state = 1;

	if (!sdp->request_queue->rq_timeout) {

		if (sdp->type != TYPE_MOD)