Recently had this Oops reported to me on the 3.10 kernel:

[  807.554955] BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
[  807.562799] IP: [<ffffffff814e6fc7>] skb_dequeue+0x47/0x70
[  807.568296] PGD 20c889067 PUD 20c8b8067 PMD 0
[  807.572769] Oops: 0002 [#1] SMP
[  807.655597] Hardware name: Dell Inc. PowerEdge R415/0DDT2D, BIOS 1.8.6 12/06/2011
[  807.663079] Workqueue: events fcoe_ctlr_recv_work [libfcoe]
[  807.668656] task: ffff88020b42a160 ti: ffff88020ae6c000 task.ti: ffff88020ae6c000
[  807.676126] RIP: 0010:[<ffffffff814e6fc7>]  [<ffffffff814e6fc7>] skb_dequeue+0x47/0x70
[  807.684046] RSP: 0000:ffff88020ae6dd70  EFLAGS: 00010097
[  807.689349] RAX: 0000000000000246 RBX: ffff8801d04d6700 RCX: 0000000000000000
[  807.696474] RDX: 0000000000000000 RSI: 0000000000000246 RDI: ffff88020df26434
[  807.703598] RBP: ffff88020ae6dd88 R08: 00000000000173e0 R09: ffff880216e173e0
[  807.710723] R10: ffffffff814e5897 R11: ffffea0007413580 R12: ffff88020df26420
[  807.717847] R13: ffff88020df26434 R14: 0000000000000004 R15: ffff8801d04c42ce
[  807.724972] FS:  00007fdaab6048c0(0000) GS:ffff880216e00000(0000) knlGS:0000000000000000
[  807.733049] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[  807.738785] CR2: 0000000000000008 CR3: 000000020cbc9000 CR4: 00000000000006f0
[  807.745910] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  807.753033] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[  807.760156] Stack:
[  807.762162]  ffff8801d04d6700 0000000000000001 ffff88020df26400 ffff88020ae6de20
[  807.769586]  ffffffffa0444409 ffff88020b046a00 ffff88020ae6dde8 ffffffff810105be
[  807.777008]  ffff88020b42a868 0000000000000000 ffff88020df264a8 ffff88020df26348
[  807.784431] Call Trace:
[  807.786885]  [<ffffffffa0444409>] fcoe_ctlr_recv_work+0x59/0x9a0 [libfcoe]
[  807.793755]  [<ffffffff810105be>] ? __switch_to+0x13e/0x4a0
[  807.799324]  [<ffffffff8107d0e6>] process_one_work+0x176/0x420
[  807.805151]  [<ffffffff8107dd0b>] worker_thread+0x11b/0x3a0
[  807.810717]  [<ffffffff8107dbf0>] ? rescuer_thread+0x350/0x350
[  807.816545]  [<ffffffff810842b0>] kthread+0xc0/0xd0
[  807.821416]  [<ffffffff810841f0>] ? insert_kthread_work+0x40/0x40
[  807.827503]  [<ffffffff8160ce2c>] ret_from_fork+0x7c/0xb0
[  807.832897]  [<ffffffff810841f0>] ? insert_kthread_work+0x40/0x40
[  807.858500] RIP  [<ffffffff814e6fc7>] skb_dequeue+0x47/0x70
[  807.864076]  RSP <ffff88020ae6dd70>
[  807.867558] CR2: 0000000000000008

Looks like the root cause is the fact that the packet recieve function
fcoe_ctlr_recv enqueues the skb to a sk_buff_head_list prior to ensuring that
the skb is unshared.  This can happen when multiple packet listeners recieve an
skb, as the deliver_skb function just increments skb->users for each handler.
As a result, having multiple users of a single skb results in multiple
manipulators of its methods, implying list corruption, and the oops recorded
above.

The fix is pretty easy, just make sure that we clone the skb if its got multiple
users with the skb_share_check function, like other protocols do.
Signed-off-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>

When repeatedly doing rmmod and modprobe on the ixgbe
driver while FCoE is active in a VN2VN configuration,
memory leaks would be discovered by kmemleak with the
following backtrace:

unreferenced object 0xffff88003d076000 (size 1024):
  comm "kworker/0:3", pid 2998, jiffies 4295436448 (age 1015.332s)
  hex dump (first 32 bytes):
    48 8a fe 6f 00 88 ff ff 00 00 00 00 00 00 00 00  H..o............
    01 00 00 00 02 00 00 00 7b ac 87 21 1b 00 00 10  ........{..!....
  backtrace:
    [<ffffffff814b308b>] kmemleak_alloc+0x5b/0xc0
    [<ffffffff8115c6e8>] __kmalloc+0xd8/0x1b0
    [<ffffffffa0216638>] fc_rport_create+0x48/0x1f0 [libfc]
    [<ffffffffa023cd86>] fcoe_ctlr_vn_add.isra.10+0x56/0x1a0 [libfcoe]
    [<ffffffffa023f440>] fcoe_ctlr_vn_recv+0x8b0/0xab0 [libfcoe]
    [<ffffffffa023fb06>] fcoe_ctlr_recv_work+0x4c6/0xf60 [libfcoe]
    [<ffffffff81067404>] process_one_work+0x1e4/0x4d0
    [<ffffffff81068def>] worker_thread+0x10f/0x380
    [<ffffffff8107019a>] kthread+0xea/0xf0
    [<ffffffff814d32ec>] ret_from_fork+0x7c/0xb0
    [<ffffffffffffffff>] 0xffffffffffffffff

This patch stops the leak of the fc_rport_priv structure.
Signed-off-by: NMark Rustad <mark.d.rustad@intel.com>
Tested-by: NJack Morgan <jack.morgan@intel.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>

When multiple FCFs in use, and first FIP Advertisement received is
with "Available for Login" i.e A bit set to 0, FCF selection will fail.
The fix is to remove the assumption in the code that first FCF is only
allowed selectable FCF.
Consider the scenario fip->fcfs contains FCF1(fabricname X, marked A=0)
FCF2(fabricname Y, marked A=1). list_first_entry(first) points to FCF1
and 1st iteration we ignore the FCF and on 2nd iteration we compare
FCF1 & FCF2 fabric name and we fails to perform FCF selection.
Signed-off-by: NKrishna Mohan <krmohan@cisco.com>
Reviewed-by: NBhanu Prakash Gollapudi <bprakash@broadcom.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>

Use preferable function name which implies using a pseudo-random
number generator.
Signed-off-by: NAkinobu Mita <akinobu.mita@gmail.com>
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Cc: Robert Love <robert.w.love@intel.com>
Cc: James Smart <james.smart@emulex.com>
Cc: Andrew Vasquez <andrew.vasquez@qlogic.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The libfc discovery layer is being initialized in the
'create' paths for both legacy libfcoe module parameters
and fcoe_sysfs control interfaces. The problem is that
for VN2VN mode the discovery layer is initialized as if
it were in 'fabric' mode and it is not re-configured when
the mode is changed to 'vn2vn'.

This patch splits out code that needs to be initialized
once and code that can, and should be, re-configured when
the mode changes. Additionally this patch makes that change
so that the discovery layer can be reconfigured to the
libfcoe implementation when in 'vn2vn' mode.
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Tested-by: NJack Morgan <jack.morgan@intel.com>
Reviewed-by: NBhanu Prakash Gollapudi <bprakash@broadcom.com>

Split discovery initialization in code that is setup once (fcoe_disc_init)
and code that can be re-configured (fcoe_disc_config).
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Tested-by: NJack Morgan <jack.morgan@intel.com>
Reviewed-by: NBhanu Prakash Gollapudi <bprakash@broadcom.com>

Currently libfcoe is doing some libfc discovery layer initialization outside of
libfc. This patch moves this code into libfc and sets up a split in discovery
(one time) initialization code and (re-configurable) settings that will come in
the next patch.
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Tested-by: NJack Morgan <jack.morgan@intel.com>
Reviewed-by: NBhanu Prakash Gollapudi <bprakash@broadcom.com>

When there are multiple FCFs in the fabric, and one of them becomes
unavailable, the fabric name for the unavailable FCF becomes 0 along
with FIP_FL_AVAIL getting reset. In this case, FCF selection logic does
not select any FCF as it first checks for conflicting FCFs (since fabric
name is 0, it fails the condition), instead of first checking if it is
usable or not. Fix it by first checking if FCF is usable and skip that
FCF, and go to the next one in the list to check if it can be selected.
Signed-off-by: NBhanu Prakash Gollapudi <bprakash@broadcom.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>

When a CVL is received while we wait to select best FCF, we drop it
without handling it. This causes initiator and the switch to go
out-of-sync. Initiator proceeds selecting one of the FCFs and tries to
send FIP FLOGI. However the switch may reject the FLOGI, as it has
cleared its internal state, and expects the initiator to start FIP
discovery protocol. Fix this condition by resetting the fcoe
controller.
Signed-off-by: NBhanu Prakash Gollapudi <bprakash@broadcom.com>
Reviewed-by: NYi Zou <yi.zou@intel.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>

This renames all random32 functions to have 'prandom_' prefix as follows:

  void prandom_seed(u32 seed);	/* rename from srandom32() */
  u32 prandom_u32(void);		/* rename from random32() */
  void prandom_seed_state(struct rnd_state *state, u64 seed);
  				/* rename from prandom32_seed() */
  u32 prandom_u32_state(struct rnd_state *state);
  				/* rename from prandom32() */

The purpose of this renaming is to prevent some kernel developers from
assuming that prandom32() and random32() might imply that only
prandom32() was the one using a pseudo-random number generator by
prandom32's "p", and the result may be a very embarassing security
exposure.  This concern was expressed by Theodore Ts'o.

And furthermore, I'm going to introduce new functions for getting the
requested number of pseudo-random bytes.  If I continue to use both
prandom32 and random32 prefixes for these functions, the confusion
is getting worse.

As a result of this renaming, "prandom_" is the common prefix for
pseudo-random number library.

Currently, srandom32() and random32() are preserved because it is
difficult to rename too many users at once.
Signed-off-by: NAkinobu Mita <akinobu.mita@gmail.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Robert Love <robert.w.love@intel.com>
Cc: Michel Lespinasse <walken@google.com>
Cc: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Cc: David Laight <david.laight@aculab.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Artem Bityutskiy <dedekind1@gmail.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch adds support for the new fcoe_sysfs
control interface to fcoe.ko. It keeps the deprecated
interface in tact and therefore either the legacy
or the new control interfaces can be used. A mixed mode
is not supported. A user must either use the new
interfaces or the old ones, but not both.

The fcoe_ctlr's link state is now driven by both the
netdev link state as well as the fcoe_ctlr_device's
enabled attribute. The link must be up and the
fcoe_ctlr_device must be enabled before the FCoE
Controller starts discovery or login.
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Acked-by: NNeil Horman <nhorman@tuxdriver.com>

The libfc is used by fcoe but fcoe agnostic,
and therefore should not have any fcoe references.

So renaming fcoe_dev_stats from libfc as its for fc_stats.
After that libfc is fcoe string free except some strings for
Open-FCoE.org.
Signed-off-by: NVasu Dev <vasu.dev@intel.com>
Acked-by : Robert Love <robert.w.love@intel.com>
Tested-by: NRoss Brattain <ross.b.brattain@intel.com>
Acked-by: NBhanu Prakash Gollapudi <bprakash@broadcom.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

This patch has the SW FCoE driver and the bnx2fc
driver make use of the new fcoe_sysfs API added
earlier in this patch series.

After this patch a fcoe_ctlr_device is allocated with
private data in this order.

+------------------+   +------------------+
| fcoe_ctlr_device |   | fcoe_ctlr_device |
+------------------+   +------------------+
| fcoe_ctlr        |   | fcoe_ctlr        |
+------------------+   +------------------+
| fcoe_interface   |   | bnx2fc_interface |
+------------------+   +------------------+

libfcoe also takes part in this new model since it
discovers and manages fcoe_fcf instances. The memory
allocation is different for FCFs. I didn't want to
impact libfcoe's fcoe_fcf processing, so this patch
creates fcoe_fcf_device instances for each discovered
fcoe_fcf. The two are paired using a (void * priv)
member of the fcoe_ctlr_device. This allows libfcoe
to continue maintaining its list of fcoe_fcf instances
and simply attaches and detaches them from existing
or new fcoe_fcf_device instances.
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Tested-by: NRoss Brattain <ross.b.brattain@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

FC-BB-6 v1.04 7.9.8.14 N_Port_ID Beacon:

"A N_Port_ID Beacon is multicast and uses the VN_Port MAC address as source
address."

Currently, libfcoe is using ENode MAC, this seems ok and functionality wise
not a problem in my back to back testing setup, however, just fix this to
make libfcoe VN2VN support more spec compliant.
Signed-off-by: NYi Zou <yi.zou@intel.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Some switch implementations (eg., HP virtual connect FlexFabric) send two MAC
descriptors in FIP FLOGI response, with first MAC descriptor (granted_mac) used
as FPMA, and the second one (fcoe_mac) used as destination address for
sending/receiving FCoE packets. fip_mac continues to be used for FIP traffic.
This patch introduces fcoe_mac in fcoe_fcf structure. For regular switches,
both fcoe_mac and fip_mac will be the same. For the switches that send
additional MAC descriptor, fcoe_mac is updated.
Signed-off-by: NBhanu Prakash Gollapudi <bprakash@broadcom.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

When handling CVL with no Vx port descriptors, lports for NPIV ports are reset
before issuing the ctlr_reset. This causes FDISCs to be issued before
successful FLOGI. Fix it by resetting the controller before resetting the
lports.
Signed-off-by: NBhanu Prakash Gollapudi <bprakash@broadcom.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Use DCB notifiers to set the skb priority to allow packets
to be steered and tagged correctly over DCB enabled drivers
that setup traffic classes.

This allows queue_mapping() routines to be removed in these
drivers that were previously inspecting the ethertype of
every skb to mark FCoE/FIP frames.
Signed-off-by: NJohn Fastabend <john.r.fastabend@intel.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Host doesnt handle CVL to NPIV instantiated ports correctly.
- As per FC-BB-5 Rev 2 CVLs with no VN_Port descriptors shall be treated as
  implicit logout of ALL vn_ports.
- CVL for NPIV ports should be handled before physical port even if descriptor
  for physical port appears before NPIV ports
Signed-off-by: NBhanu Prakash Gollapudi <bprakash@broadcom.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <jbottomley@parallels.com>

Signed-off-by: NKirill A. Shutemov <kirill@shutemov.name>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

Fixes generated by 'codespell' and manually reviewed.
Signed-off-by: NLucas De Marchi <lucas.demarchi@profusion.mobi>

Now we can include the fcoe_transport.c to the build of the kernel libfcoe
module. Move the module information to fcoe_transport, and it will have
all the module parameters later for the create/destroy/enable/disable of an
FCoE instance.
Signed-off-by: NYi Zou <yi.zou@intel.com>
Signed-off-by: NBhanu Prakash Gollapudi <bprakash@broadcom.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

The existing libfcoe.c is mostly for FIP support, rename it to reflect that
fact and so we can add fcoe_transport.c to the make file to include both
into the libfcoe kernel module.

[ Minor modifications by Robert Love converting a few
  "__attribute__((packed))" modifiers to "__packed" to remove new
  checkpatch.pl WARNINGS ]
Signed-off-by: NYi Zou <yi.zou@intel.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

libfcoe kernel module debug macros will used by the fcoe transport code
as well when later it gets added.
Signed-off-by: NYi Zou <yi.zou@intel.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

Neaten several calls to fip_select() by having it return the
pointer to the new FCF.
Signed-off-by: NJoe Eykholt <jeykholt@cisco.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

When there are several FCFs to choose from, the one most likely
to accept a FLOGI on certian switches is the one that last
answered a multicast solicit.

So, when receiving an advertisement, move the FCF to the front
of the list so that it gets chosen first among those with the
same priority.

Without this, more FLOGIs need to be sent in a test with
multiple FCFs and a switch in NPV mode, but it still
eventually finds one that accepts the FLOGI.
Signed-off-by: NJoe Eykholt <jeykholt@cisco.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

When multiple FCFs to the same fabric exist, the debug messages
all look alike.   Change the message to include the MAC address.
Signed-off-by: NJoe Eykholt <jeykholt@cisco.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

Switches using multiple-FCFs may reject FLOGI in order to
balance the load between multiple FCFs.  Even though the FCF
was available, it may have more load at the point we actually
send the FLOGI.

If the FLOGI fails, select a different FCF
if possible, among those with the same priority.  If no other
FCF is available, just deliver the reject to libfc for retry.
Signed-off-by: NJoe Eykholt <jeykholt@cisco.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

The check for conflicting fabrics in fcoe_ctlr_select()
ignores any FCFs that aren't usable.  This is a minor
problem now but becomes more pronounced after later patches.
Signed-off-by: NJoe Eykholt <jeykholt@cisco.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

Move some of the code in fcoe_ctlr_timer_work() to
fcoe_ctlr_select() so that it can be shared
with another function in a forthcoming patch.
Signed-off-by: NJoe Eykholt <jeykholt@cisco.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

Move the announcement code to a separate function for reuse in
a forthcoming patch.

For messages regarding FCF timeout and selection, use the
previously-announced FCF MAC address (dest_addr) in the fcoe_ctlr struct.
Only print (announce) the FCF if it is new.   Print MAC for
timed-out or deselected FCFs.
Signed-off-by: NJoe Eykholt <jeykholt@cisco.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

Add missing newlines.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

Fix: When FIP frame is received, function fcoe_ctlr_vn_recv calls function
fcoe_ctlr_vn_parse which does memset for addr (&buf.rdata) which leads to
memory corruption. Code was trying to treat "buf" as struct but it was defined
as union. Fix is to change from union to struct for "buf" in function fcoe_ctlr_vn_recv.

Technical Details: N/A
Signed-off-by: NKiran Patil <kiran.patil@intel.com>
Acked-by: NJoe Eykholt <jeykholt@cisco.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

This check prevents FCF selection in NPV mode due to zero fabric name
in that case and in turn flogi fails. Though NPV mode should not have
this zero and should be fixed there also but spec also does not require
initiator to ensure that fabric name must be non-zero, therefore dropping
this check to get flogi working in NPV mode.
Signed-off-by: NVasu Dev <vasu.dev@intel.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

Incoming requests shouldn't require a local exchange if we're
just going to reply with one or two frames and don't expect
anything further.  Don't allocate exchanges for such requests
until requested by the upper-layer protocol.

The sequence is always NULL for new requests, so remove
that as an argument to request handlers.

Also change the first argument to lport->tt.seq_els_rsp_send
from the sequence pointer to the received frame pointer, to
supply the exchange IDs and destination ID info.
Signed-off-by: NJoe Eykholt <jeykholt@cisco.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

In VN2VN mode, map_dest means to use the default VN2VN OUI.
Change code that uses the default FCoE OUI to use the one
set in the fcoe_ctlr struct.
Signed-off-by: NJoe Eykholt <jeykholt@cisco.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

When sending a FLOGI LS_ACC, which we only do in point-to-multipoint
mode, the MAC descriptor should have the granted MAC set to
0x0efd00 || D_ID.

When sending an LS_RJT, there should be no MAC descriptor.

When sending either an LS_ACC or LS_RJT, the subcode should indicate
an reply, not a request.
Signed-off-by: NJoe Eykholt <jeykholt@cisco.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

The FC-BB-6 committee is proposing a new FIP usage model called
VN_port to VN_port mode.  It allows VN_ports to discover each other
over a loss-free L2 Ethernet without any FCF or Fibre-channel fabric
services.  This is point-to-multipoint.  There is also a variant
of this called point-to-point which provides for making sure there
is just one pair of ports operating over the Ethernet fabric.

We add these new states:  VNMP_START, _PROBE1, _PROBE2, _CLAIM, and _UP.
These usually go quickly in that sequence.  After waiting a random
amount of time up to 100 ms in START, we select a pseudo-random
proposed locally-unique port ID and send out probes in states PROBE1
and PROBE2, 100 ms apart.  If no probe responses are heard, we
proceed to CLAIM state 400 ms later and send a claim notification.
We wait another 400 ms to receive claim responses, which give us
a list of the other nodes on the network, including their FC-4
capabilities.  After another 400 ms we go to VNMP_UP state and
should start interoperating with any of the nodes for whic we
receivec claim responses.  More details are in the spec.j

Add the new mode as FIP_MODE_VN2VN.  The driver must specify
explicitly that it wants to operate in this mode.  There is
no automatic detection between point-to-multipoint and fabric
mode, and the local port initialization is affected, so it isn't
anticipated that there will ever be any such automatic switchover.

It may eventually be possible to have both fabric and VN2VN
modes on the same L2 network, which may be done by two separate
local VN_ports (lports).

When in VN2VN mode, FIP replaces libfc's fabric-oriented discovery
module with its own simple code that adds remote ports as they
are discovered from incoming claim notifications and responses.
These hooks are placed by fcoe_disc_init().

A linear list of discovered vn_ports is maintained under the
fcoe_ctlr struct.  It is expected to be short for now, and
accessed infrequently.  It is kept under RCU for lock-ordering
reasons.  The lport and/or rport mutexes may be held when we
need to lookup a fcoe_vnport during an ELS send.

Change fcoe_ctlr_encaps() to lookup the destination vn_port in
the list of peers for the destination MAC address of the
FIP-encapsulated frame.

Add a new function fcoe_disc_init() to initialize just the
discovery portion of libfcoe for VN2VN mode.
Signed-off-by: NJoe Eykholt <jeykholt@cisco.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

Enhancement: add debug messages at all state transitions.
Signed-off-by: NJoe Eykholt <jeykholt@cisco.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

There are three modes that libfcoe currently supports, and a new one
is coming.  Change the fcoe_ctlr_init() interface to add the mode
desired.  This should not change any functionality.
Signed-off-by: NJoe Eykholt <jeykholt@cisco.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

It turns out most of the FIP work is now done from worker threads
or process context now, so there's no need to use a spin lock.

Change to use mutex instead of spin lock and delayed_work instead
of a timer.

This will make it nicer for the VN_port to VN_port feature that
will interact more with the libfc layers requiring that
spinlocks not be held.
Signed-off-by: NJoe Eykholt <jeykholt@cisco.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>