The driver creates its own per-CPU threads which are updated based on
CPU hotplug events. It is also possible to use kworkers and remove some
of the kthread infrastrucure.

The code checked ->thread to decide if there is an active per-CPU
thread. By using the kworker infrastructure this is no longer
possible (or required). The thread pointer is saved in `kthread' instead
of `thread' so anything trying to use thread is caught by the
compiler. Currently only the bnx2fc driver is using struct fcoe_percpu_s
and the kthread member.

After a CPU went offline, we may still enqueue items on the "offline"
CPU. This isn't much of a problem. The work will be done on a random
CPU. The allocated crc_eof_page page won't be cleaned up. It is probably
expected that the CPU comes up at some point so it should not be a
problem. The crc_eof_page memory is released of course once the module
is removed.

This patch was only compile-tested due to -ENODEV.

Cc: Vasu Dev <vasu.dev@intel.com>
Cc: "James E.J. Bottomley" <jejb@linux.vnet.ibm.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: fcoe-devel@open-fcoe.org
Cc: linux-scsi@vger.kernel.org
Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Tested-by: NJohannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

When setting up CRC offload set ip_summed to CHECKSUM_PARTIAL
instead of CHECKSUM_UNNECESSARY. This is consistent with the
definition of CHECKSUM_PARTIAL.

The only driver that seems to be advertising NETIF_F_FCOE_CRC is
ixgbe. AFICT the driver does not look at ip_summed for FCOE and
just assumes that CRC is being offloaded.
Signed-off-by: NTom Herbert <tom@herbertland.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch changes the !blk-mq path to the same defaults as the blk-mq
I/O path by always enabling block tagging, and always using host wide
tags.  We've had blk-mq available for a few releases so bugs with
this mode should have been ironed out, and this ensures we get better
coverage of over tagging setup over different configs.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Acked-by: NJens Axboe <axboe@kernel.dk>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NJames Bottomley <JBottomley@Odin.com>

There is a label pointing to the start of a while loop and a goto
nested only in the loop. The goto jumps to the label in some cases.
Replace the goto and the label by simple continue.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Acked-by: NVasu Dev <vasu.dev@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Odin.com>

In little endian cases, the macro htons unfolds to __swab16 which
provides special case for constants. In big endian cases,
__constant_htons and htons expand directly to the same expression.
So, replace __constant_htons with htons with the goal of getting
rid of the definition of __constant_htons completely.

The semantic patch that performs this transformation is as follows:

@@expression x;@@

- __constant_htons(x)
+ htons(x)
Signed-off-by: NVaishali Thakkar <vthakkar1994@gmail.com>
Acked-by: NVasu Dev <vasu.dev@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Odin.com>

Since we got rid of ordered tag support in 2010 the prime use case of
switching on and off ordered tags has been obsolete.  The other function
of enabling/disabling tagging entirely has only been correctly implemented
by the 53c700 driver and isn't generally useful.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NBart Van Assche <bvanassche@acm.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com
Reviewed-by: NHannes Reinecke <hare@suse.de>

Drop the now unused reason argument from the ->change_queue_depth method.
Also add a return value to scsi_adjust_queue_depth, and rename it to
scsi_change_queue_depth now that it can be used as the default
->change_queue_depth implementation.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMike Christie <michaelc@cs.wisc.edu>
Reviewed-by: NHannes Reinecke <hare@suse.de>

All drivers use the implementation for ramping the queue up and down, so
instead of overloading the change_queue_depth method call the
implementation diretly if the driver opts into it by setting the
track_queue_depth flag in the host template.

Note that a few drivers validated the new queue depth in their
change_queue_depth method, but as we never go over the queue depth
set during slave_configure or the sysfs file this isn't nessecary
and can safely be removed.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMike Christie <michaelc@cs.wisc.edu>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Reviewed-by: NVenkatesh Srinivas <venkateshs@google.com>

Always returns the same skb it gets, so change to void.
Signed-off-by: NJiri Pirko <jiri@resnulli.us>
Acked-by: NPravin B Shelar <pshelar@nicira.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Allow a driver to ask for block layer tags by setting .use_blk_tags in the
host template, in which case it will always see a valid value in
request->tag, similar to the behavior when using blk-mq.  This means even
SCSI "untagged" commands will now have a tag, which is especially useful
when using a host-wide tag map.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMike Christie <michaelc@cs.wisc.edu>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: NHannes Reinecke <hare@suse.de>

Most drivers use exactly the same implementation, so provide it as a
library function.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NBart Van Assche <bvanassche@acm.org>
Reviewed-by: NMike Christie <michaelc@cs.wisc.edu>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: NHannes Reinecke <hare@suse.de>

schedule(), io_schedule() and schedule_timeout() always return
with TASK_RUNNING state set, so one more setting is unnecessary.

(All places in patch are visible good, only exception is
 kiblnd_scheduler() from:

      drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd_cb.c

 Its schedule() is one line above standard 3 lines of unified diff)

No places where set_current_state() is used for mb().
Signed-off-by: NKirill Tkhai <ktkhai@parallels.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1410529254.3569.23.camel@tkhai
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Anil Belur <askb23@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dave Kleikamp <shaggy@kernel.org>
Cc: David Airlie <airlied@linux.ie>
Cc: David Howells <dhowells@redhat.com>
Cc: Dmitry Eremin <dmitry.eremin@intel.com>
Cc: Frank Blaschka <blaschka@linux.vnet.ibm.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Isaac Huang <he.huang@intel.com>
Cc: James E.J. Bottomley <JBottomley@parallels.com>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: J. Bruce Fields <bfields@fieldses.org>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Laura Abbott <lauraa@codeaurora.org>
Cc: Liang Zhen <liang.zhen@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Masaru Nomura <massa.nomura@gmail.com>
Cc: Michael Opdenacker <michael.opdenacker@free-electrons.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Neil Brown <neilb@suse.de>
Cc: Oleg Drokin <green@linuxhacker.ru>
Cc: Peng Tao <bergwolf@gmail.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Robert Love <robert.w.love@intel.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: Ursula Braun <ursula.braun@de.ibm.com>
Cc: Zi Shen Lim <zlim.lnx@gmail.com>
Cc: devel@driverdev.osuosl.org
Cc: dm-devel@redhat.com
Cc: dri-devel@lists.freedesktop.org
Cc: fcoe-devel@open-fcoe.org
Cc: jfs-discussion@lists.sourceforge.net
Cc: linux390@de.ibm.com
Cc: linux-afs@lists.infradead.org
Cc: linux-cris-kernel@axis.com
Cc: linux-kernel@vger.kernel.org
Cc: linux-nfs@vger.kernel.org
Cc: linux-parisc@vger.kernel.org
Cc: linux-raid@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: linux-scsi@vger.kernel.org
Cc: qla2xxx-upstream@qlogic.com
Cc: user-mode-linux-devel@lists.sourceforge.net
Cc: user-mode-linux-user@lists.sourceforge.net
Signed-off-by: NIngo Molnar <mingo@kernel.org>

Replace various -20/+19 hardcoded nice values with MIN_NICE/MAX_NICE.
Signed-off-by: NDongsheng Yang <yangds.fnst@cn.fujitsu.com>
Acked-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NPeter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/ff13819fd09b7a5dba5ab5ae797f2e7019bdfa17.1394532288.git.yangds.fnst@cn.fujitsu.com
Cc: devel@driverdev.osuosl.org
Cc: devicetree@vger.kernel.org
Cc: fcoe-devel@open-fcoe.org
Cc: linux390@de.ibm.com
Cc: linux-kernel@vger.kernel.org
Cc: linux-mm@kvack.org
Cc: linux-s390@vger.kernel.org
Cc: linux-scsi@vger.kernel.org
Cc: nbd-general@lists.sourceforge.net
Cc: ocfs2-devel@oss.oracle.com
Cc: openipmi-developer@lists.sourceforge.net
Cc: qla2xxx-upstream@qlogic.com
Cc: linux-arch@vger.kernel.org
[ Consolidated the patches, twiddled the changelog. ]
Signed-off-by: NIngo Molnar <mingo@kernel.org>

Subsystems that want to register CPU hotplug callbacks, as well as perform
initialization for the CPUs that are already online, often do it as shown
below:

	get_online_cpus();

	for_each_online_cpu(cpu)
		init_cpu(cpu);

	register_cpu_notifier(&foobar_cpu_notifier);

	put_online_cpus();

This is wrong, since it is prone to ABBA deadlocks involving the
cpu_add_remove_lock and the cpu_hotplug.lock (when running concurrently
with CPU hotplug operations).

Instead, the correct and race-free way of performing the callback
registration is:

	cpu_notifier_register_begin();

	for_each_online_cpu(cpu)
		init_cpu(cpu);

	/* Note the use of the double underscored version of the API */
	__register_cpu_notifier(&foobar_cpu_notifier);

	cpu_notifier_register_done();

Fix the fcoe code in scsi by using this latter form of callback registration.

Cc: Robert Love <robert.w.love@intel.com>
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: NSrivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Preliminary to removing compare_ether_addr altogether:

Use the new bool function ether_addr_equal to add
some clarity and reduce the likelihood for misuse
of compare_ether_addr for sorting.

Done via cocci script:

$ cat compare_ether_addr.cocci
@@
expression a,b;
@@
-	!compare_ether_addr(a, b)
+	ether_addr_equal(a, b)

@@
expression a,b;
@@
-	compare_ether_addr(a, b)
+	!ether_addr_equal(a, b)

@@
expression a,b;
@@
-	!ether_addr_equal(a, b) == 0
+	ether_addr_equal(a, b)

@@
expression a,b;
@@
-	!ether_addr_equal(a, b) != 0
+	!ether_addr_equal(a, b)

@@
expression a,b;
@@
-	ether_addr_equal(a, b) == 0
+	!ether_addr_equal(a, b)

@@
expression a,b;
@@
-	ether_addr_equal(a, b) != 0
+	ether_addr_equal(a, b)

@@
expression a,b;
@@
-	!!ether_addr_equal(a, b)
+	ether_addr_equal(a, b)
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>

fnic doesn't use any of the create/destroy/enable/disable interfaces
either from the (legacy) module paramaters or the (new) fcoe_sysfs
interfaces. When fcoe_sysfs was introduced fnic wasn't changed since
it wasn't using the interfaces. libfcoe incorrectly assumed that that
all of its users were using fcoe_sysfs and when adding and deleting
FCFs would assume the existance of a fcoe_ctlr_device. fnic was not
allocating this structure because it doesn't care about the standard
user interfaces (fnic starts on link only). If/When libfcoe tried to use
the fcoe_ctlr_device's lock for the first time a NULL pointer exception
would be triggered.

Since fnic doesn't care about sysfs or user interfaces, the solution
is to drop libfcoe's assumption that all drivers are using fcoe_sysfs.

This patch accomplishes this by changing some of the structure
relationships.

We need a way to determine when a LLD is using fcoe_sysfs or not and
we can do that by checking for the existance of the fcoe_ctlr_device.
Prior to this patch, it was assumed that the fcoe_ctlr structure was
allocated with the fcoe_ctlr_device and immediately followed it in
memory. To reach the fcoe_ctlr_device we would simply go back in memory
from the fcoe_ctlr to get the fcoe_ctlr_device.

Since fnic doesn't allocate the fcoe_ctlr_device, we cannot keep that
assumption. This patch adds a pointer from the fcoe_ctlr to the
fcoe_ctlr_device. For bnx2fc and fcoe we will continue to allocate the
two structures together, but then we'll set the ctlr->cdev pointer
to point at the fcoe_ctlr_device. fnic will not change and will continue
to allocate the fcoe_ctlr itself, and ctlr->cdev will remain NULL.

When libfcoe adds fcoe_fcf's to the fcoe_ctlr it will check if ctlr->cdev
is set and only if so will it continue to interact with fcoe_sysfs.
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Acked-by: NNeil Horman <nhorman@tuxdriver.com>
Tested-by: NHiral Patel <hiralpat@cisco.com>

FCoE debug statements must end in a newline. Add one where it is missing.
Signed-off-by: NBart Van Assche <bvanassche@acm.org>
Cc: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>

the return codes from fcoe_rcv should be NET_RX_*, not 0 or -1.
Signed-off-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>

Based on my last patch I noticed that fcoe_rcv has a simmilar problem, in that
it manipulates the passed in skb without checking to see if it has other users.
Making manipulations to a shared skb can result in various corruptions.

Easy fix, just make sure the skb is unshared prior to doing anything with it.
Signed-off-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>

This patch fixes a smatch warning as below:

smatch warnings:
drivers/scsi/fcoe/fcoe.c:782 fcoe_fdmi_info() warn: 'fdmi' puts 896 bytes on
stack
Reported-by: NFengguang Wu <fengguang.wu@intel.com>
Signed-off-by: NNeerav Parikh <Neerav.Parikh@intel.com>
Tested-by: NJack Morgan <jack.morgan@intel.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>

fcoe_xmit was coded such that it would skip the vlan net device/layer
and instead set some vlan flags and transmit on the real net device.
The real net device has code that would add the vlan tag for fcoe skbs.
This avoids some extra processing for data frames and provides a small
performance improvement.

Since fcoe_xmit was not using the vlan net device, __vlan_put_tag
within the real net device's xmit routine was ultimately being
called to set the vlan tag.

With the below change the behavior of __vlan_put_tag changed slightly,
it now sets the skb->protocol = vlan_proto. vlan_proto was not a field
being set by fcoe_xmit, so the skb->protocol is now not being set to
ETH_P_8021Q, as it should be.

This patch converts fcoe_xmit to use the vlan_put_tag routine which
will tag the skb and fcoe will continue to transmit fcoe skbs on the
real net device.

For reference, the below change was the one that altered the
__vlan_put_tag behavior.

  commit 86a9bad3
  Author: Patrick McHardy <kaber@trash.net>
  Date:   Fri Apr 19 02:04:30 2013 +0000

      net: vlan: add protocol argument to packet tagging functions

      Add a protocol argument to the VLAN packet tagging functions. In case of HW
      tagging, we need that protocol available in the ndo_start_xmit functions,
      so it is stored in a new field in the skb. The new field fits into a hole
      (on 64 bit) and doesn't increase the sks's size.
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Acked-by: NNeil Horman <nhorman@tuxdriver.com>
Acked-by: NJohn Fastabend <john.r.fastabend@intel.com>

So far, only net_device * could be passed along with netdevice notifier
event. This patch provides a possibility to pass custom structure
able to provide info that event listener needs to know.
Signed-off-by: NJiri Pirko <jiri@resnulli.us>

v2->v3: fix typo on simeth
	shortened dev_getter
	shortened notifier_info struct name
v1->v2: fix notifier_call parameter in call_netdevice_notifier()
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Rename the hardware VLAN acceleration features to include "CTAG" to indicate
that they only support CTAGs. Follow up patches will introduce 802.1ad
server provider tagging (STAGs) and require the distinction for hardware not
supporting acclerating both.
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We can deadlock (s_active and fcoe_config_mutex) if a
port is being destroyed at the same time one is being created.

[ 4200.503113] ======================================================
[ 4200.503114] [ INFO: possible circular locking dependency detected ]
[ 4200.503116] 3.8.0-rc5+ #8 Not tainted
[ 4200.503117] -------------------------------------------------------
[ 4200.503118] kworker/3:2/2492 is trying to acquire lock:
[ 4200.503119]  (s_active#292){++++.+}, at: [<ffffffff8122d20b>] sysfs_addrm_finish+0x3b/0x70
[ 4200.503127]
but task is already holding lock:
[ 4200.503128]  (fcoe_config_mutex){+.+.+.}, at: [<ffffffffa02f3338>] fcoe_destroy_work+0xe8/0x120 [fcoe]
[ 4200.503133]
which lock already depends on the new lock.

[ 4200.503135]
the existing dependency chain (in reverse order) is:
[ 4200.503136]
-> #1 (fcoe_config_mutex){+.+.+.}:
[ 4200.503139]        [<ffffffff810c7711>] lock_acquire+0xa1/0x140
[ 4200.503143]        [<ffffffff816ca7be>] mutex_lock_nested+0x6e/0x360
[ 4200.503146]        [<ffffffffa02f11bd>] fcoe_enable+0x1d/0xb0 [fcoe]
[ 4200.503148]        [<ffffffffa02f127d>] fcoe_ctlr_enabled+0x2d/0x50 [fcoe]
[ 4200.503151]        [<ffffffffa02ffbe8>] store_ctlr_enabled+0x38/0x90 [libfcoe]
[ 4200.503154]        [<ffffffff81424878>] dev_attr_store+0x18/0x30
[ 4200.503157]        [<ffffffff8122b750>] sysfs_write_file+0xe0/0x150
[ 4200.503160]        [<ffffffff811b334c>] vfs_write+0xac/0x180
[ 4200.503162]        [<ffffffff811b3692>] sys_write+0x52/0xa0
[ 4200.503164]        [<ffffffff816d7159>] system_call_fastpath+0x16/0x1b
[ 4200.503167]
-> #0 (s_active#292){++++.+}:
[ 4200.503170]        [<ffffffff810c680f>] __lock_acquire+0x135f/0x1c90
[ 4200.503172]        [<ffffffff810c7711>] lock_acquire+0xa1/0x140
[ 4200.503174]        [<ffffffff8122c626>] sysfs_deactivate+0x116/0x160
[ 4200.503176]        [<ffffffff8122d20b>] sysfs_addrm_finish+0x3b/0x70
[ 4200.503178]        [<ffffffff8122b2eb>] sysfs_hash_and_remove+0x5b/0xb0
[ 4200.503180]        [<ffffffff8122f3d1>] sysfs_remove_group+0x61/0x100
[ 4200.503183]        [<ffffffff814251eb>] device_remove_groups+0x3b/0x60
[ 4200.503185]        [<ffffffff81425534>] device_remove_attrs+0x44/0x80
[ 4200.503187]        [<ffffffff81425e97>] device_del+0x127/0x1c0
[ 4200.503189]        [<ffffffff81425f52>] device_unregister+0x22/0x60
[ 4200.503191]        [<ffffffffa0300970>] fcoe_ctlr_device_delete+0xe0/0xf0 [libfcoe]
[ 4200.503194]        [<ffffffffa02f1b5c>] fcoe_interface_cleanup+0x6c/0xa0 [fcoe]
[ 4200.503196]        [<ffffffffa02f3355>] fcoe_destroy_work+0x105/0x120 [fcoe]
[ 4200.503198]        [<ffffffff8107ee91>] process_one_work+0x1a1/0x580
[ 4200.503203]        [<ffffffff81080c6e>] worker_thread+0x15e/0x440
[ 4200.503205]        [<ffffffff8108715a>] kthread+0xea/0xf0
[ 4200.503207]        [<ffffffff816d70ac>] ret_from_fork+0x7c/0xb0

[ 4200.503209]
other info that might help us debug this:

[ 4200.503211]  Possible unsafe locking scenario:

[ 4200.503212]        CPU0                    CPU1
[ 4200.503213]        ----                    ----
[ 4200.503214]   lock(fcoe_config_mutex);
[ 4200.503215]                                lock(s_active#292);
[ 4200.503218]                                lock(fcoe_config_mutex);
[ 4200.503219]   lock(s_active#292);
[ 4200.503221]
 *** DEADLOCK ***

[ 4200.503223] 3 locks held by kworker/3:2/2492:
[ 4200.503224]  #0:  (fcoe){.+.+.+}, at: [<ffffffff8107ee2b>] process_one_work+0x13b/0x580
[ 4200.503228]  #1:  ((&port->destroy_work)){+.+.+.}, at: [<ffffffff8107ee2b>] process_one_work+0x13b/0x580
[ 4200.503232]  #2:  (fcoe_config_mutex){+.+.+.}, at: [<ffffffffa02f3338>] fcoe_destroy_work+0xe8/0x120 [fcoe]
[ 4200.503236]
stack backtrace:
[ 4200.503238] Pid: 2492, comm: kworker/3:2 Not tainted 3.8.0-rc5+ #8
[ 4200.503240] Call Trace:
[ 4200.503243]  [<ffffffff816c2f09>] print_circular_bug+0x1fb/0x20c
[ 4200.503246]  [<ffffffff810c680f>] __lock_acquire+0x135f/0x1c90
[ 4200.503248]  [<ffffffff810c463a>] ? debug_check_no_locks_freed+0x9a/0x180
[ 4200.503250]  [<ffffffff810c7711>] lock_acquire+0xa1/0x140
[ 4200.503253]  [<ffffffff8122d20b>] ? sysfs_addrm_finish+0x3b/0x70
[ 4200.503255]  [<ffffffff8122c626>] sysfs_deactivate+0x116/0x160
[ 4200.503258]  [<ffffffff8122d20b>] ? sysfs_addrm_finish+0x3b/0x70
[ 4200.503260]  [<ffffffff8122d20b>] sysfs_addrm_finish+0x3b/0x70
[ 4200.503262]  [<ffffffff8122b2eb>] sysfs_hash_and_remove+0x5b/0xb0
[ 4200.503265]  [<ffffffff8122f3d1>] sysfs_remove_group+0x61/0x100
[ 4200.503273]  [<ffffffff814251eb>] device_remove_groups+0x3b/0x60
[ 4200.503275]  [<ffffffff81425534>] device_remove_attrs+0x44/0x80
[ 4200.503277]  [<ffffffff81425e97>] device_del+0x127/0x1c0
[ 4200.503279]  [<ffffffff81425f52>] device_unregister+0x22/0x60
[ 4200.503282]  [<ffffffffa0300970>] fcoe_ctlr_device_delete+0xe0/0xf0 [libfcoe]
[ 4200.503285]  [<ffffffffa02f1b5c>] fcoe_interface_cleanup+0x6c/0xa0 [fcoe]
[ 4200.503287]  [<ffffffffa02f3355>] fcoe_destroy_work+0x105/0x120 [fcoe]
[ 4200.503290]  [<ffffffff8107ee91>] process_one_work+0x1a1/0x580
[ 4200.503292]  [<ffffffff8107ee2b>] ? process_one_work+0x13b/0x580
[ 4200.503295]  [<ffffffffa02f3250>] ? fcoe_if_destroy+0x230/0x230 [fcoe]
[ 4200.503297]  [<ffffffff81080c6e>] worker_thread+0x15e/0x440
[ 4200.503299]  [<ffffffff81080b10>] ? busy_worker_rebind_fn+0x100/0x100
[ 4200.503301]  [<ffffffff8108715a>] kthread+0xea/0xf0
[ 4200.503304]  [<ffffffff81087070>] ? kthread_create_on_node+0x160/0x160
[ 4200.503306]  [<ffffffff816d70ac>] ret_from_fork+0x7c/0xb0
[ 4200.503308]  [<ffffffff81087070>] ? kthread_create_on_node+0x160/0x160
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Tested-by: NJack Morgan <jack.morgan@intel.com>

This patch fixes following deadlock caused by destroying of
an FCoE interface with active NPIV ports on that interface.

    Call Trace:
    [<ffffffff814b7e88>] schedule+0x64/0x66
    [<ffffffff814b6b4f>] schedule_timeout+0x36/0xe3
    [<ffffffff81070c55>] ? update_curr+0xd6/0x110
    [<ffffffff81071f6b>] ? hrtick_update+0x1b/0x4d
    [<ffffffff81072405>] ? dequeue_task_fair+0x1ca/0x1d9
    [<ffffffff8106a369>] ? need_resched+0x1e/0x28
    [<ffffffff814b7d14>] wait_for_common+0x9b/0xf1
    [<ffffffff8106e7be>] ? try_to_wake_up+0x1e0/0x1e0
    [<ffffffff814b7e22>] wait_for_completion+0x1d/0x1f
    [<ffffffff8105ae82>] flush_workqueue+0x116/0x2a1
    [<ffffffff8105b357>] drain_workqueue+0x66/0x14c
    [<ffffffff8105b8ef>] destroy_workqueue+0x1a/0xcf
    [<ffffffffa009211e>] fc_remove_host+0x154/0x17f [scsi_transport_fc]
    [<ffffffffa00edbb8>] fcoe_if_destroy+0x184/0x1c9 [fcoe]
    [<ffffffffa00edc28>] fcoe_destroy_work+0x2b/0x44 [fcoe]
    [<ffffffff8105a82a>] process_one_work+0x1a8/0x2a4
    [<ffffffffa00edbfd>] ? fcoe_if_destroy+0x1c9/0x1c9 [fcoe]
    [<ffffffff8105c396>] worker_thread+0x1db/0x268
    [<ffffffff810604a3>] ? wake_up_bit+0x2a/0x2a
    [<ffffffff8105c1bb>] ? manage_workers.clone.16+0x1f6/0x1f6
    [<ffffffff8105ffd6>] kthread+0x6f/0x77
    [<ffffffff814c0304>] kernel_thread_helper+0x4/0x10
    [<ffffffff8105ff67>] ? kthread_freezable_should_stop+0x4b/0x4b

    Call Trace:
    [<ffffffff814b7e88>] schedule+0x64/0x66
    [<ffffffff814b8041>] schedule_preempt_disabled+0xe/0x10
    [<ffffffff814b70a1>] __mutex_lock_common.clone.5+0x117/0x17a
    [<ffffffff814b7117>] __mutex_lock_slowpath+0x13/0x15
    [<ffffffff814b6f76>] mutex_lock+0x23/0x37
    [<ffffffff8125b890>] ? list_del+0x11/0x30
    [<ffffffffa00edc84>] fcoe_vport_destroy+0x43/0x5f [fcoe]
    [<ffffffffa009130a>] fc_vport_terminate+0x48/0x110 [scsi_transport_fc]
    [<ffffffffa00913ef>] fc_vport_sched_delete+0x1d/0x79 [scsi_transport_fc]
    [<ffffffff8105a82a>] process_one_work+0x1a8/0x2a4
    [<ffffffffa00913d2>] ? fc_vport_terminate+0x110/0x110 [scsi_transport_fc]
    [<ffffffff8105c396>] worker_thread+0x1db/0x268
    [<ffffffff8105c1bb>] ? manage_workers.clone.16+0x1f6/0x1f6
    [<ffffffff8105ffd6>] kthread+0x6f/0x77
    [<ffffffff814c0304>] kernel_thread_helper+0x4/0x10
    [<ffffffff8105ff67>] ? kthread_freezable_should_stop+0x4b/0x4b
    [<ffffffff814c0300>] ? gs_change+0x13/0x13

A prior attempt to fix this issue is posted here:
http://lists.open-fcoe.org/pipermail/devel/2012-October/012318.html
or
http://article.gmane.org/gmane.linux.scsi.open-fcoe.devel/11924

Based on feedback and discussion with Neil Horman it seems that the above patch
may have a case where the fcoe_vport_destroy() and fcoe_destroy_work() can
race; hence that patch has been withdrawn with this patch that is trying to
solve the same problem in a different way.

In the current approach instead of removing the fcoe_config_mutex from the
vport_delete callback function; I've chosen to delete all the NPIV ports first
on a given root lport before continuing with the removal of the root lport.
Signed-off-by: NNeerav Parikh <Neerav.Parikh@intel.com>
Tested-by: NMarcus Dennis <marcusx.e.dennis@intel.com>
Acked-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>

When creating an fcoe interfce, we call fcoe_link_speed_update before we add the
lports fcoe interface to the fc_hostlist.  Since network device events like
NETDEV_CHANGE are only processed if an fcoe interface is found with an
underlying netdev that matches the netdev of the event.  Since this processing
in fcoe_device_notification is how link_speed changes get communicated to the
libfc  code (via fcoe_link_speed_update), we have a race condition - if a
NETDEV_CHANGE event is sent after the call to fcoe_link_speed_update in
fcoe_netdev_config, but before we add the interface to the fc_hostlist, we will
loose the event and attributes like /sys/class/fc_host/hostX/speed will not get
updated properly.

Fix this by moving the add to the fc_hostlist above the serialized call to
fcoe_netdev_config, ensuring that we catch netdev envents before we make a
direct call to fcoe_link_speed_update.

Also use this opportunity to clean up access to the fc_hostlist a bit by
creating a fcoe_hostlist_del accessor and replacing the cleanup in fcoe_exit to
use it properly.

Tested by myself successfully

[ Comment over 80 chars broken into multi-line by Robert Love to
  satisfy checkpatch.pl ]
Signed-off-by: NNeil Horman <nhorman@tuxdriver.com>
Reviewed-by: NYi Zou <yi.zou@intel.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>

Similarly they can be moved into libfcoe instead of being private to fcoe now.
Also add comments particularly on the term LESB to the corresponding function.
Signed-off-by: NYi Zou <yi.zou@intel.com>
Cc: Bhanu Prakash Gollapudi <bprakash@broadcom.com>
Tested-by: NMarcus Dennis <marcusx.e.dennis@intel.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>

With the previous patch, fcoe_link_speed_update() can be moved into libfcoe and
exported to used by fcoe, bnx2fc, and etc.
Signed-off-by: NYi Zou <yi.zou@intel.com>
Cc: Bhanu Prakash Gollapudi <bprakash@broadcom.com>
Tested-by: NMarcus Dennis <marcusx.e.dennis@intel.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>

Adds support to fcoe_port's newly added get_netdev fucntion pointer.
Signed-off-by: NYi Zou <yi.zou@intel.com>
Cc: Bhanu Prakash Gollapudi <bprakash@broadcom.com>
Tested-by: NMarcus Dennis <marcusx.e.dennis@intel.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>

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>

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: NRobert Love <robert.w.love@intel.com>
Acked-by: NNeil Horman <nhorman@tuxdriver.com>

SCSI errors were generated while writing to LUNs
connected via NPIV ports.

Debugging this it was found that the FCoE packets
transmitted via the NPIV ports were not tagged with
correct user priority as negotiated with peer by DCB
agent. This resulted in FCoE traffic going with priority
zero(0) that did not have priority flow control (PFC)
enabled for it. The initiator after transferring data
to the target never saw any reply indicating the transfer
was complete. This resulted in error recovery (ABTS) and
SCSI command retries by the scsi-mid layer; eventually
resulting in I/O errors.

This patch fixes this issue by keeping the FCoE user
priority information in the fcoe_interface instance
that is common for both the physical port as well as
NPIV ports connected to that physical port; instead
of storing it in fcoe_port structure that has a per
port instance.
Signed-off-by: NNeerav Parikh <Neerav.Parikh@intel.com>
Acked-by: NYi Zou <yi.zou@intel.com>
Acked-by: NJohn Fastabend <john.r.fastabend@intel.com>
Tested-by: NMarcus Dennis <marcusx.e.dennis@intel.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Noticed that we can shuffle the code around in fcoe_percpu_receive_thread a bit
and avoid taking the fcoe_rx_list lock twice per iteration.  This should improve
throughput somewhat.  With this change we take the lock, and check for new
frames in a single critical section.  Only if the list is empty do we drop the
lock and re-acquire it after being signaled to wake up.

Change Notes:
v2) did some further cleanup on the patch by replacing the 2nd call of
spin_lock/splice_init with a goto to the top of the outer loop.  This allows me
to change the inner while loop to an if conditional and remove the sencond check
of kthread_should_stop.  Based on suggestion from Vasu Dev.
Signed-off-by: NNeil Horman <nhorman@tuxdriver.com>
Acked-by: NVasu Dev <vasu.dev@intel.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.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>

Currently the fcoe_ctlr associated with an interface is allocated
as a member of struct fcoe_interface. This causes problems when
attempting to use the new fcoe_sysfs APIs which allow us to allocate
the fcoe_interface as private data to the fcoe_ctlr_device instance.
The problem is that libfcoe wants to be able use pointer math to find a
fcoe_ctlr's fcoe_ctlr_device as well as finding a fcoe_ctlr_device's
assocated fcoe_ctlr. To do this we need to allocate the
fcoe_ctlr_device, with private data for the LLD. The private data
contains the fcoe_ctlr and its private data is the fcoe_interface.
This patch only allocates the fcoe_interface with the fcoe_ctlr, the
fcoe_ctlr_device will be added in a later patch, which will complete
the below diagram-

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

This prep work will allow us to go from a fcoe_ctlr_device instance
to its fcoe_ctlr as well as from a fcoe_ctlr to its fcoe_ctlr_device
once the fcoe_sysfs API is in use (later patches in this series).
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>

We moved the locking in dd060e74 "[SCSI] fcoe: remove frame dropping
code from fcoe_percpu_clean" but this unlock was missed.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

The rtnl_mutex was held to protect calls to dev_uc_add
and dev_uc_del. Holding rtnl is not required as those
functions make use of the netif_addr_lock* API to
protect the MAC changing.

This change fixes the following regression by removing
the rtnl usage when fcoe_update_src_mac is called.

https://bugzilla.kernel.org/show_bug.cgi?id=42918

the existing dependency chain (in reverse order) is:

-> #1 (&fip->ctlr_mutex){+.+...}:
       [<c1091f70>] lock_acquire+0x80/0x1b0
       [<c147655d>] mutex_lock_nested+0x6d/0x340
       [<f8970c32>] fcoe_ctlr_link_up+0x22/0x180 [libfcoe]
       [<f894620e>] fcoe_create+0x47e/0x6e0 [fcoe]
       [<f8973dd3>] fcoe_transport_create+0x143/0x250 [libfcoe]
       [<c10527e0>] param_attr_store+0x30/0x60
       [<c1052696>] module_attr_store+0x26/0x40
       [<c11a201e>] sysfs_write_file+0xae/0x100
       [<c11449df>] vfs_write+0x8f/0x160
       [<c1144cbd>] sys_write+0x3d/0x70
       [<c147a0c4>] syscall_call+0x7/0xb

-> #0 (rtnl_mutex){+.+.+.}:
       [<c109164b>] __lock_acquire+0x140b/0x1720
       [<c1091f70>] lock_acquire+0x80/0x1b0
       [<c147655d>] mutex_lock_nested+0x6d/0x340
       [<c13a10c4>] rtnl_lock+0x14/0x20
       [<f89445ac>] fcoe_update_src_mac+0x2c/0xb0 [fcoe]
       [<f8971712>] fcoe_ctlr_timer_work+0x712/0xb60 [libfcoe]
       [<c104fb69>] process_one_work+0x179/0x5d0
       [<c10502f1>] worker_thread+0x121/0x2d0
       [<c10550ed>] kthread+0x7d/0x90
       [<c1481a82>] kernel_thread_helper+0x6/0x10

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&fip->ctlr_mutex);
                               lock(rtnl_mutex);
                               lock(&fip->ctlr_mutex);
  lock(rtnl_mutex);

 *** DEADLOCK ***
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Tested-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

The fcoe controller has back references, therefore defer
releasing master lport which gets freed along scsi_host_put
and then free it once fcoe interface is fully cleaned.
Signed-off-by: NVasu Dev <vasu.dev@intel.com>
Acked-by: NNeil Horman <nhorman@tuxdriver.com>
Tested-by: NRoss Brattain <ross.b.brattain@intel.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Remove lport from net device and then do synchronize net device to flush
inflight rx frames for the lport before doing fcoe_percpu_clean.

In case of master lport, remove all rx packet handlers completely and
then only do fcoe_percpu_clean. This required splitting fcoe_interface_cleanup
to do remove part separately and for that added func fcoe_interface_remove
and then  call it from fcoe_if_destory before doing fcoe_percpu_clean.
However if fcoe_interface_remove() is already called then
don't call again from fcoe_interface_cleanup() to preserve its
existing flows.

This patch along with Neil's other patch to avoid soft irq context
on ingress will avoid passing up frames on disabled lport as
discussed in this mail thread:-
http://lists.open-fcoe.org/pipermail/devel/2012-February/011947.htmlSigned-off-by: NVasu Dev <vasu.dev@intel.com>
Acked-by: NNeil Horman <nhorman@tuxdriver.com>
Tested-by: NRoss Brattain <ross.b.brattain@intel.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>