Commit Graph

122 Commits

Author SHA1 Message Date
Vasu Dev 5919a59503 [SCSI] fcoe: prep work to completely remove fc_transport_fcoe code
The fcoe transport code was added for generic FCoE transport
infrastructure to allow additional offload related module loading
on demand, this is not required anymore after recently added
different offload approach by having offload related func ops
in netdev.

This patch removes fcoe transport related code use, calls functions
directly between existing libfcoe.c and fcoe_sw.c for now, for
example fcoe_sw_destroy and fcoe_sw_create calling.

The fcoe_sw.c and libfcoe.c code will be further consolidated in
later patches and then also the default fcoe sw transport code
file fcoe_sw.c will be completely removed.

The fcoe transport code files are completely removed in next
patch to keep this patch simple for reviewing.

[This patch is an update to a previous patch. This update
resolves a build error as well as fixes a defect related to
not calling fc_release_transport().]

Signed-off-by: Vasu Dev <vasu.dev@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-04-03 09:23:00 -05:00
Robert Love 8976f424d4 [SCSI] fcoe: create/destroy fcoe Rx threads on CPU hotplug events
This patch adds support for dynamically created Rx threads
upon CPU hotplug events.

There were existing synchronization problems that this patch
attempts to resolve. The main problem had to do with fcoe_rcv()
running in a different context than the hotplug notifications.
This opened the possiblity that fcoe_rcv() would target a Rx
thread for a skb. However, that thread could become NULL if
the CPU was made offline.

This patch uses the Rx queue's (a skb_queue) lock to protect
the thread it's associated with and we use the 'thread' member
of the fcoe_percpu_s to determine if the thread is ready to
accept new skbs.

The patch also attempts to do a better job of cleaning up, both
if hotplug registration fails as well as when the module is
removed.

Contribution provided by Joe Eykholt <jeykholt@cisco.com> to
fix incorrect use of __cpuinitdata.

Signed-off-by: Yi Zou <yi.zou@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-04-03 09:22:59 -05:00
Robert Love 582b45bc57 [SCSI] fcoe: Use per-CPU kernel function for dev_stats instead of an array
Remove the hotplug creation of dev_stats, we allocate for all possible CPUs
now when we allocate the lport.

v2: Durring the 2.6.30 merge window, before these patches were comitted,
'percpu_ptr' was renamed 'per_cpu_ptr'. This latest update updates this
patch for the name change.

Signed-off-by: Yi Zou <yi.zou@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-04-03 09:22:58 -05:00
Robert Love 5e5e92df49 [SCSI] fcoe: Use percpu kernel funcs for struct fcoe_percpu_s
Convert fcoe_percpu array to use the per-cpu variables
that the kernel provides. Use the kernel's functions to
access this structure.

The cpu member of the fcoe_percpu_s is no longer needed,
so this patch removes it too.

Signed-off-by: Yi Zou <yi.zou@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-04-03 09:22:57 -05:00
Robert Love 38eccabd10 [SCSI] fcoe: Initialize all possilbe skb_queue(s) when module is loaded
Currently the skb_queue is initialized every time the associated
CPU goes online. This patch has libfcoe initializing the skb_queue
for all possible CPUs when the module is loaded.

This patch also re-orders some declarations in the fcoe_rcv()
function so the structure declarations are grouped before
the primitive declarations.

Lastly, this patch converts all CPU indicies to use unsigned int
since CPU indicies should not be negative.

Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-04-03 09:22:57 -05:00
Yi Zou 07c00ec449 [SCSI] fcoe: fcoe fc crc offload indication by skb->ip_summed
If LLD supports FCCRC offload, it should set ip_summed to be
CHECKSUM_UNNECESSARY so we don't have to do CRC check again.

Signed-off-by: Yi Zou <yi.zou@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-13 15:15:48 -05:00
Yi Zou e056200736 [SCSI] fcoe: add support to FCoE offload support in fcoe_sw through net_device
This adds implementation of ddp_setup()/ddp_done() in fcoe_sw for its
fcoe_sw_libfc_fcn_templ.

Signed-off-by: Yi Zou <yi.zou@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-13 15:15:31 -05:00
Yi Zou 39ca9a065a [SCSI] fcoe: add support to large send by gso through net_device for fcoe_sw
Change fcoe_xmit to setup gso for LLD LSO offload as well as CRC offload

Signed-off-by: Yi Zou <yi.zou@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-13 15:14:54 -05:00
Yi Zou ea1e9a9df5 [SCSI] fcoe, libfc: check offload features from LLD through netdev
This checks if net_devices supports FCoE offload ops in netdev_ops and it
if it does, then sets up the corresponding flags in the associated fc_lport.

For large send offload, the maximum length supported in one large send is now
described by the added lso_max in fc_lport, which is setup initially from
netdev->gso_max_size.

Signed-off-by: Yi Zou <yi.zou@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-13 15:13:48 -05:00
Yi Zou 211c738d86 [SCSI] net, fcoe: add ETH_P_FCOE for Fibre Channel over Ethernet (FCoE)
This adds eth type ETH_P_FCOE for Fibre Channel over Ethernet (FCoE),
consequently, the ETH_P_FCOE from fc_fcoe.h and fcoe skb->protocol
is not set as ETH_P_FCOE.

Signed-off-by: Yi Zou <yi.zou@intel.com>
Acked-by: David Miller <davem@davemloft.net>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-13 15:09:00 -05:00
Robert Love 4469c195da [SCSI] fcoe: Change fcoe receive thread nice value from 19 (lowest priority) to -20
This change makes the fcoe Rx threads have the same nice value
as lpfc and qla2xxx Rx threads.

Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-10 09:10:02 -05:00
Chris Leech 55c8bafba5 [SCSI] fcoe: fix handling of pending queue, prevent out of order frames (v3)
In fcoe_check_wait_queue() the queue length could temporarily drop to 0,
before the last frame was successfully sent.  This resulted in out of order
data frames within a single sequence, leading to IO timeout errors.

This builds on the approach from Vasu Dev to only fix the queue management in
fcoe_check_wait_queue, where my first patch added locking to the transmit
path even when the pending queue was not in use.

This patch continues to use fcoe_pending_queue.qlen instead of introducing a
new length counter, but takes precautions to ensure it never drops to 0 before
the final frame in the queue has successfully been passed to the netdev qdisc
layer.  It also includes some cleanup of fcoe_check_wait_queue and removes the
fcoe_insert_wait_queue(_head) wrapper functions.

Signed-off-by: Chris Leech <christopher.leech@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-10 09:09:40 -05:00
Vasu Dev c826a31457 [SCSI] fcoe: Out of order tx frames was causing several check condition SCSI status
frames followed by these errors in log.

	[sdp] Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE,SUGGEST_OK
	[sdp] Sense Key : Aborted Command [current]
	[sdp] Add. Sense: Data phase error

This was causing some test apps to exit due to write failure under heavy
load.

This was due to a race around adding and removing tx frame skb in
fcoe_pending_queue, Chris Leech helped me to find that brief unlocking
period when pulling skb from fcoe_pending_queue in various contexts
(fcoe_watchdog and fcoe_xmit) and then adding skb back into fcoe_pending_queue
up on a failed fcoe_start_io could change skb/tx frame order in
fcoe_pending_queue. Thanks Chris.

This patch allows only single context to pull skb from fcoe_pending_queue
at any time to prevent above described ordering issue/race by use of
fcoe_pending_queue_active flag.

This patch simplified fcoe_watchdog with modified fcoe_check_wait_queue by
use of FCOE_LOW_QUEUE_DEPTH instead previously used several conditionals
to clear and set lp->qfull.

I think FCOE_MAX_QUEUE_DEPTH with FCOE_LOW_QUEUE_DEPTH  will work better
in re/setting lp->qfull and these could be fine tuned for performance.

Signed-off-by: Vasu Dev <vasu.dev@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-10 09:09:21 -05:00
Roel Kluin e904158159 [SCSI] fcoe: fix kfree(skb)
Use kfree_skb instead of kfree for struct sk_buff pointers.

Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-10 09:09:01 -05:00
Robert Love 03ec862dff [SCSI] fcoe: Correct fcoe_transports initialization vs. registration
The registration function shouldn't initialize the mutex or
list head. The fcoe SW transport should initialize itself
before registering.

Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-10 09:06:17 -05:00
Robert Love a468f328ad [SCSI] fcoe: Use setup_timer() and mod_timer()
Use helper functions for watchdog timer setup.

Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-10 09:05:57 -05:00
Robert Love fc47ff6b1b [SCSI] libfc, fcoe: Remove unnecessary cast by removing inline wrapper
Comment from "Andrew Morton <akpm@linux-foundation.org>"

> +{
> +     return (struct fcoe_softc *)lport_priv(lp);

unneeded/undesirable cast of void*.  There are probably zillions of
instances of this - there always are.

This whole inline function was unnecessary. The FCoE layer knows
that it's data structure is stored in the lport private data, it
can just access it from lport_priv().

Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-10 09:05:35 -05:00
Robert Love b2ab99c9a3 [SCSI] libfc, fcoe: Cleanup function formatting and minor typos
1) There were a few functions with a strange layout, i.e. all
   arguments on the second line, when not necessary.

   Where ever possible I moved the return value to the same line
   as the function name. However, when the line was too long
   to have a single argument on the same line I moved the
   return value to above line. For example:

   <short return> <function name>(<arg 1>, <arg2>)

   and

   <very long return value>
   <function name>(<arg1>,
		   <arg2>)

2) Removed one extra whitespace line

3) Fixed two typos

Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-10 09:05:09 -05:00
Robert Love 34f42a070f [SCSI] libfc, fcoe: Fix kerneldoc comments
1) Added '()' for function names in kerneldoc comments

2) Changed comment bookends from '**/' to '*/'. The comment on the the
   mailing list was that '**/' "is consistently unconventional.  Not
   wrong, just odd." The Documentation/kernel-doc-nano-HOWTO.txt
   states that kerneldoc comment blocks should end with '**/' but most
   (if not all) instance I found under drivers/scsi/ were only using
   the '*/' so I converted to that style.

3) Removed incorrect linebreaks in kerneldoc comments where found

4) Removed a few unnecessary blank comment lines in kerneldoc comment
   blocks

Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-10 09:04:40 -05:00
Vasu Dev bc0e17f691 [SCSI] libfc, fcoe: fixed locking issues with lport->lp_mutex around lport->link_status
The fcoe_xmit could call fc_pause in case the pending skb queue len is larger
than FCOE_MAX_QUEUE_DEPTH, the fc_pause was trying to grab lport->lp_muex to
change lport->link_status and that had these issues :-

1. The fcoe_xmit was getting called with bh disabled, thus causing
"BUG: scheduling while atomic" when grabbing lport->lp_muex with bh disabled.

2. fc_linkup and fc_linkdown function calls lport_enter function with
lport->lp_mutex held and these enter function in turn calls fcoe_xmit to send
lport related FC frame, e.g. fc_linkup => fc_lport_enter_flogi to send flogi
req. In this case grabbing the same lport->lp_mutex again in fc_puase from
fcoe_xmit would cause deadlock.

The lport->lp_mutex was used for setting FC_PAUSE in fcoe_xmit path but
FC_PAUSE bit was not used anywhere beside just setting and clear this
bit in lport->link_status, instead used a separate field qfull in fc_lport
to eliminate need for lport->lp_mutex to track pending queue full condition
and in turn avoid above described two locking issues.

Also added check for lp->qfull in fc_fcp_lport_queue_ready to trigger
SCSI_MLQUEUE_HOST_BUSY when lp->qfull is set to prevent more scsi-ml cmds
while lp->qfull is set.

This patch eliminated FC_LINK_UP and FC_PAUSE and instead used dedicated
fields in fc_lport for this, this simplified all related conditional
code.

Also removed fc_pause and fc_unpause functions and instead used newly added
lport->qfull directly in fcoe.

Signed-off-by: Vasu Dev <vasu.dev@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-03-06 15:37:49 -06:00
James Bottomley 56b854bb31 [SCSI] fcoe: fix incorrect use of struct module
This structure may not be defined if CONFIG_MODULE=n, so never deref
it.  Change uses of module->name to module_name(module) and corrects
some dyslexic printks and docbook comments.

Reported-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-12-30 13:08:37 -06:00
Robert Love 85b4aa4926 [SCSI] fcoe: Fibre Channel over Ethernet
Encapsulation protocol for running Fibre Channel over Ethernet interfaces.
Creates virtual Fibre Channel host adapters using libfc.

This layer is the LLD to the scsi-ml. It allocates the Scsi_Host, utilizes
libfc for Fibre Channel protocol processing and interacts with netdev to
send/receive Ethernet packets.

Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-12-29 11:24:33 -06:00