Firmware: add iSCSI iBFT Support

Add /sysfs/firmware/ibft/[initiator|targetX|ethernetX] directories along with
text properties which export the the iSCSI Boot Firmware Table (iBFT)
structure.

What is iSCSI Boot Firmware Table?  It is a mechanism for the iSCSI tools to
extract from the machine NICs the iSCSI connection information so that they
can automagically mount the iSCSI share/target.  Currently the iSCSI
information is hard-coded in the initrd.  The /sysfs entries are read-only
one-name-and-value fields.

The usual set of data exposed is:

# for a in `find /sys/firmware/ibft/ -type f -print`; do  echo -n "$a: ";  cat $a; done
/sys/firmware/ibft/target0/target-name: iqn.2007.com.intel-sbx44:storage-10gb
/sys/firmware/ibft/target0/nic-assoc: 0
/sys/firmware/ibft/target0/chap-type: 0
/sys/firmware/ibft/target0/lun: 00000000
/sys/firmware/ibft/target0/port: 3260
/sys/firmware/ibft/target0/ip-addr: 192.168.79.116
/sys/firmware/ibft/target0/flags: 3
/sys/firmware/ibft/target0/index: 0
/sys/firmware/ibft/ethernet0/mac: 00:11:25:9d:8b:01
/sys/firmware/ibft/ethernet0/vlan: 0
/sys/firmware/ibft/ethernet0/gateway: 192.168.79.254
/sys/firmware/ibft/ethernet0/origin: 0
/sys/firmware/ibft/ethernet0/subnet-mask: 255.255.252.0
/sys/firmware/ibft/ethernet0/ip-addr: 192.168.77.41
/sys/firmware/ibft/ethernet0/flags: 7
/sys/firmware/ibft/ethernet0/index: 0
/sys/firmware/ibft/initiator/initiator-name: iqn.2007-07.com:konrad.initiator
/sys/firmware/ibft/initiator/flags: 3
/sys/firmware/ibft/initiator/index: 0

For full details of the IBFT structure please take a look at:
ftp://ftp.software.ibm.com/systems/support/system_x_pdf/ibm_iscsi_boot_firmware_table_v1.02.pdf

[akpm@linux-foundation.org: fix build]
Signed-off-by: Konrad Rzeszutek <konradr@linux.vnet.ibm.com>
Cc: Mike Christie <michaelc@cs.wisc.edu>
Cc: Peter Jones <pjones@redhat.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 23 insertions, 0 deletions

diff --git a/Documentation/ABI/testing/sysfs-ibft b/Documentation/ABI/testing/sysfs-ibft
new file mode 100644
index 000000000000..c2b7d1154bec
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-ibft
@@ -0,0 +1,23 @@
+What:           /sys/firmware/ibft/initiator
+Date:           November 2007
+Contact:        Konrad Rzeszutek <ketuzsezr@darnok.org>
+Description:    The /sys/firmware/ibft/initiator directory will contain
+                files that expose the iSCSI Boot Firmware Table initiator data.
+                Usually this contains the Initiator name.
+
+What:           /sys/firmware/ibft/targetX
+Date:           November 2007
+Contact:        Konrad Rzeszutek <ketuzsezr@darnok.org>
+Description:    The /sys/firmware/ibft/targetX directory will contain
+                files that expose the iSCSI Boot Firmware Table target data.
+                Usually this contains the target's IP address, boot LUN,
+                target name, and what NIC it is associated with. It can also
+                contain the CHAP name (and password), the reverse CHAP
+                name (and password)
+
+What:           /sys/firmware/ibft/ethernetX
+Date:           November 2007
+Contact:        Konrad Rzeszutek <ketuzsezr@darnok.org>
+Description:    The /sys/firmware/ibft/ethernetX directory will contain
+                files that expose the iSCSI Boot Firmware Table NIC data.
+                This can this can the IP address, MAC, and gateway of the NIC.