libfcoe, fcoe, bnx2fc: Add new fcoe control interface

This patch does a few things.

1) Makes /sys/bus/fcoe/ctlr_{create,destroy} interfaces.
   These interfaces take an <ifname> and will either
   create an FCoE Controller or destroy an FCoE
   Controller depending on which file is written to.

   The new FCoE Controller will start in a DISABLED
   state and will not do discovery or login until it
   is ENABLED. This pause will allow us to configure
   the FCoE Controller before enabling it.

2) Makes the 'mode' attribute of a fcoe_ctlr_device
   writale. This allows the user to configure the mode
   in which the FCoE Controller will start in when it
   is ENABLED.

   Possible modes are 'Fabric', or 'VN2VN'.

   The default mode for a fcoe_ctlr{,_device} is 'Fabric'.
   Drivers must implement the set_fcoe_ctlr_mode routine
   to support this feature.

   libfcoe offers an exported routine to set a FCoE
   Controller's mode. The mode can only be changed
   when the FCoE Controller is DISABLED.

   This patch also removes the get_fcoe_ctlr_mode pointer
   in the fcoe_sysfs function template, the code in
   fcoe_ctlr.c to get the mode and the assignment of
   the fcoe_sysfs function pointer to the fcoe_ctlr.c
   implementation (in fcoe and bnx2fc). fcoe_sysfs can
   return that value for the mode without consulting the
   LLD.

3) Make a 'enabled' attribute of a fcoe_ctlr_device. On a
   read, fcoe_sysfs will return the attribute's value. On
   a write, fcoe_sysfs will call the LLD (if there is a
   callback) to notifiy that the enalbed state has changed.

This patch maintains the old FCoE control interfaces as
module parameters, but it adds comments pointing out that
the old interfaces are deprecated.

Signed-off-by: Robert Love <robert.w.love@intel.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>

1 files changed, 40 insertions, 1 deletions

diff --git a/Documentation/ABI/testing/sysfs-bus-fcoe b/Documentation/ABI/testing/sysfs-bus-fcoe
index 971dc22e6c2a..21640eaad371 100644
--- a/Documentation/ABI/testing/sysfs-bus-fcoe
+++ b/Documentation/ABI/testing/sysfs-bus-fcoe
@@ -1,14 +1,53 @@
+What:           /sys/bus/fcoe/
+Date:           August 2012
+KernelVersion:  TBD
+Contact:        Robert Love <robert.w.love@intel.com>, devel@open-fcoe.org
+Description:    The FCoE bus. Attributes in this directory are control interfaces.
+Attributes:
+
+        ctlr_create: 'FCoE Controller' instance creation interface. Writing an
+                     <ifname> to this file will allocate and populate sysfs with a
+                     fcoe_ctlr_device (ctlr_X). The user can then configure any
+                     per-port settings and finally write to the fcoe_ctlr_device's
+                     'start' attribute to begin the kernel's discovery and login
+                     process.
+
+        ctlr_destroy: 'FCoE Controller' instance removal interface. Writing a
+                       fcoe_ctlr_device's sysfs name to this file will log the
+                       fcoe_ctlr_device out of the fabric or otherwise connected
+                       FCoE devices. It will also free all kernel memory allocated
+                       for this fcoe_ctlr_device and any structures associated
+                       with it, this includes the scsi_host.
+
 What:           /sys/bus/fcoe/devices/ctlr_X
 Date:           March 2012
 KernelVersion:  TBD
 Contact:        Robert Love <robert.w.love@intel.com>, devel@open-fcoe.org
-Description:    'FCoE Controller' instances on the fcoe bus
+Description:    'FCoE Controller' instances on the fcoe bus.
+                The FCoE Controller now has a three stage creation process.
+                1) Write interface name to ctlr_create 2) Configure the FCoE
+                Controller (ctlr_X) 3) Enable the FCoE Controller to begin
+                discovery and login. The FCoE Controller is destroyed by
+                writing it's name, i.e. ctlr_X to the ctlr_delete file.
+
 Attributes:
 
         fcf_dev_loss_tmo: Device loss timeout peroid (see below). Changing
                           this value will change the dev_loss_tmo for all
                           FCFs discovered by this controller.
 
+        mode:             Display or change the FCoE Controller's mode. Possible
+                          modes are 'Fabric' and 'VN2VN'. If a FCoE Controller
+                          is started in 'Fabric' mode then FIP FCF discovery is
+                          initiated and ultimately a fabric login is attempted.
+                          If a FCoE Controller is started in 'VN2VN' mode then
+                          FIP VN2VN discovery and login is performed. A FCoE
+                          Controller only supports one mode at a time.
+
+        enabled:          Whether an FCoE controller is enabled or disabled.
+                          0 if disabled, 1 if enabled. Writing either 0 or 1
+                          to this file will enable or disable the FCoE controller.
+
         lesb/link_fail:   Link Error Status Block (LESB) link failure count.
 
         lesb/vlink_fail:  Link Error Status Block (LESB) virtual link