Critical Errors:
- Correctly handle non-zero return lpfc_workq_post_event and return ENOMEM
- Save the irq level when locking the host_lock in lpfc_findnode_did
Bug Fixes:
- Adjust payload_length and request_length for sli4_config mailbox commands.
- Add the freed sgl/XRI to the tail of the list rather than to the head.
- Set the FC_VPORT_NEEDS_INIT_VPI on vport deletes and check it before
issuing a fdisc on an els retry.
- Only call lpfc_hba_init_link() if phba->cfg_suppress_link_up
is LPFC_INITIALIZE_LINK.
- Add support for SLI-4 Performance Hints
Signed-off-by: Alex Iannicelli <alex.iannicelli@emulex.com>
Signed-off-by: James Smart <james.smart@emulex.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
'!' has higher precedence than '&'. CFGTBL_ChangeReq is 0x1 so the
original code is equivelent to if (!doorbell_value) {...
Signed-off-by: Dan Carpenter <error27@gmail.com>
Acked-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
We can get completions left over from before the attempted reset which
will interfere with the kdump. Better to just not make the attempt in
that case.
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Controller will transfer only 32-bits on completion if it
knows we are only using 32-bit tags. Also, some newer controllers
apparently (and erroneously) require that we only use 32-bit tags,
and that we inform the controller of this.
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
It's not enough to simple avoid putting the board into performant
mode, as we have to set up the interrupts differently, etc. When
I originally tested this module parameter, I tested it incorrectly
without realizing it, and the driver was running in performant mode
the whole time unbeknownst to me.
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Driver's internal queues should be FIFO, not LIFO.
This is a port of an almost identical patch from cciss by Jens Axboe.
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
In a multiple configuration change scenario a remove notification can be
followed by an immediate add notification for the same device, which
will cause the device to be removed but never added back. This patch
fixes the problem by ensuring that in such situations the device will be
added back.
Signed-off-by: Kleber Sacilotto de Souza <klebers@linux.vnet.ibm.com>
Acked-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
The conversion is quite complex given that the libata new error
handler has to be hooked into the current libsas timeout and error
handling. The way this is done is to process all the failed commands
via libsas first, but if they have no underlying sas task (and they're
on a sata device) assume they are destined for the libata error
handler and send them accordingly.
Finally, activate the port recovery of the libata error handler for
each port known to the host. This is somewhat suboptimal, since that
port may not need recovering, but given the current architecture of
the libata error handler, it's the only way; and the spurious
activation is harmless.
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Right at the moment, the libata error handler is incredibly
monolithic. This makes it impossible to use from composite drivers
like libsas and ipr which have to handle error themselves in the first
instance.
The essence of the change is to split the monolithic error handler
into two components: one which handles a queue of ata commands for
processing and the other which handles the back end of readying a
port. This allows the upper error handler fine grained control in
calling libsas functions (and making sure they only get called for ATA
commands whose lower errors have been fixed up).
Cc: Tejun Heo <tj@kernel.org>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
The SCSI host eh_cmd_q should be protected by the host lock (not the
port lock). This probably doesn't matter that much at the moment,
since we try to serialise the add and eh pieces, but it might matter
in future for more convenient error handling. Plus this switches
libata to the standard eh pattern where you lock, remove from the cmd
queue to a local list and unlock and then operate on the local list.
Cc: Tejun Heo <tj@kernel.org>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
For historical reasons, libsas uses the scsi host lock as the ata port
lock, and libata always uses the ata host. For the old eh, this was
largely irrelevant since the two locks were never mixed inside the
code. However, the new eh has a case where it nests acquisition of
the host lock inside the port lock (this does look rather deadlock
prone). Obviously this would be an instant deadlock if the port lock
were the host lock, so switch the libsas paths to use the ata host
lock as well.
Cc: Tejun Heo <tj@kernel.org>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
The function ata_sas_port_init() has always really done its own thing.
However, as a precursor to moving to the libata new eh, it has to be
properly using the standard libata scan paths. This means separating
the current libata scan paths into pieces which can be shared with
libsas and pieces which cant (really just the async call and the host
scan).
Cc: Tejun Heo <tj@kernel.org>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Adding MODULE_VERSION for scsi_dh_rdac. This will be helpful sometimes
to get the code level without looking at the code.
Signed-off-by: Babu Moger <babu.moger@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
instead of doing sizeof(struct X) it's better to do sizeof(*v) where v
is the variable pointing to struct X.
Signed-off-by: Hillf Danton <dhillf@gmail.com>
Signed-off-by: Babu Moger <babu.moger@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
During one of our testing, we noticed that mode select command sent
from the host did not have the lun_table updated.
Problem is root caused to the way lun table is updated. Lun table
update was done after the call to blk_rq_map_kern is made. This was
causing problem because kernel uses bounce buffer(bio_copy_kern) if
the address is not aligned. The command buffer updated after the
call(blk_rq_map_kern) was not going on the wire. Moved the code to
update the lun_table before the call to fix the problem.
Signed-off-by: Babu Moger <babu.moger@lsi.com>
Signed-off-by: Somasundaram Krishnasamy <Somasundaram.Krishnasamy@lsi.com>
Signed-off-by: Yanling Qi <Yanling.Qi@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Bus reset is not required for SAS Controller. It is valid for mptspi
and mptfc, but for mptsas it is not required. It is an extra work for
Error handling escallation for mptsas. Removing bus reset from error
handling will eventually speedup Error handling for SAS controller.
Signed-off-by: Kashyap Desai <kashyap.desai@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
SAS1.0 Controller was not able to detect SAS2.0 Expanders due to Link
RATE detection was limited to 1.5 Gbps and 3.0 Gbps for SAS1
controllers. Added detection for 6.0 Gbps link. Now, user can mix-up
6.0 Gpbs links with SAS1.0 controller.
e.g SAS1.0 HBA <----> SAS2.0 Expander <------> SAS2.0 Expander <--------> SAS1.0 Drive.
Signed-off-by: Kashyap Desai <kashyap.desai@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
To facilitate LLDDs to reuse the code, skb queue related functions are moved to
libfcoe, so that both fcoe and bnx2fc drivers can use them. The common structures
fcoe_port, fcoe_percpu_s are moved to libfcoe. fcoe_port will now have an
opaque pointer that points to corresponding driver's interface structure.
Also, fcoe_start_io and fcoe_fc_crc are moved to libfcoe.
As part of this change, fixed fcoe_start_io to return ENOMEM if
skb_clone fails.
Signed-off-by: Bhanu Prakash Gollapudi <bprakash@broadcom.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
fcoe uses the system_wq to destroy ports and the work items need to be
flushed before the driver is unloaded. As the work items free the
containing data structure, they can't be flushed directly. The
workqueue should be flushed instead.
Also, the destruction works can be chained - ie. destruction of a port
may lead to destruction of another port where the work item for the
former queues the work for the latter. Currently, the depth of chain
can be at most two and fcoe_exit() makes sure everything is complete
by calling flush_scheduled_work() twice.
With commit c8efcc25 (workqueue: allow chained queueing during
destruction), destroy_workqueue() can take care of chained works on
workqueue destruction. Add and use fcoe_wq instead. Simply
destroying fcoe_wq on driver unload takes care of flushing.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
This patch enables LLD to listen to rport events and perform LLD
specific operations based on the rport event. This patch also stores
sp_features and spp_type in rdata for further reference by LLD.
Signed-off-by: Bhanu Prakash Gollapudi <bprakash@broadcom.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Problem:
From initaitor machine, when queried role of target (other end of connection),
it is "initiator", hence SCSI-ml doesn't send any LUN Inquiry commands.
Fix:
If there is a registered target for FC_TYPE_FCP, extend lport's params
(capability) to be target as well, By default lport params are
INITIATOR only. Having this fix, caused initiator to send SCSI LUN
inquiry command to target.
Signed-off-by: Kiran Patil <kiran.patil@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Remove the existing sysfs entry points of the fcoe.ko module parameters that
are used to create/destroy/enable/disable an FCoE instance, rather, use the
newly added fcoe transport code to attach itself as an FCoE transport provider
when fcoe.ko gets loaded. There is no functionality change on the logic of
fcoe interacts with upper libfc and lower netdev. The fcoe transport only acts
as thin layer to provide a unified interface for all fcoe transport providers
so all FCoE instances on any network interfaces from all vendors can be
managed through the same Open-FCoE.org's user space tool package, which also
has full DCB support.
Signed-off-by: Yi Zou <yi.zou@intel.com>
Signed-off-by: Bhanu Prakash Gollapudi <bprakash@broadcom.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Prepare the fcoe to convert it to use the newly added fcoe transport, making
it as the default fcoe transport provider for libfcoe. This patch is to rename
some of the variables to avoid any confusing names later as now there are
several transports in the same file.
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@suse.de>
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: Yi Zou <yi.zou@intel.com>
Signed-off-by: Bhanu Prakash Gollapudi <bprakash@broadcom.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James 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: Yi Zou <yi.zou@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Add the new fcoe_transport.c file that implements basic fcoe transport
interface. Eventually, the sysfs entries to create/destroy/enable/disable
an FCoE instance will be coming to the fcoe transport layer, who does a
look-up to find the corresponding transport provide and pass the corresponding
action over to the identified provider.
The fcoe.ko will become the default fcoe transport provider that can support
FCoE on any given netdev interfaces, as the Open-FCoE.org's default software
FCoE HBA solution. Any vendor specific FCoE HBA driver that is built on top
of Open-FCoE's kernel stack of libfc & libfcoe as well as the user land tool
of fcoe-utils can easily plug-in and start running FCoE on their network
interfaces. The fcoe.ko will be converted to act as the default provider if
no vendor specific transport provider is found, as it is always added to the
very end of the list of attached transports.
Signed-off-by: Yi Zou <yi.zou@intel.com>
Signed-off-by: Bhanu Prakash Gollapudi <bprakash@broadcom.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
add the fcoe_transport struct to the common libfcoe.h header so all fcoe
transport provides can use it to attach itself as an fcoe transport. This
is the header part, and the next patch will be the transport code itself.
Signed-off-by: Yi Zou <yi.zou@intel.com>
Signed-off-by: Bhanu Prakash Gollapudi <bprakash@broadcom.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James 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: Yi Zou <yi.zou@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Problem:
In case of exchange responder case, EMA selection was defaulted to the
last EMA from EMA list (lport.ema_list). If exchange ID is selected
from offload pool and not setup DDP, resulting into incorrect
selection of EMA, and eventually dropping the packet because unable to
find exchange.
Fix:
Enhanced the exchange ID selection (depending upon request type and
exchange responder) Made necessary enhancement in EMA selection
algorithm.
Signed-off-by: Kiran Patil <kiran.patil@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Target modules using lport->tt.seq_assign() get a hold on the
exchange but have no way of releasing it. Add that.
Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
This patch removes the use of the Scsi_Host's host_lock
within fc_queuecommand. It also removes the DEF_SCSI_QCMD
usage so that libfc has fully moved on to the new
queuecommand interface.
Signed-off-by: Robert Love <robert.w.love@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Reviewed-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
When sending an outgoing PRLI as an initiator, get the parameters
from registered providers so that they all get a chance to decide
on roles.
The passive provider is called last, and could override the
initiator role.
Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
When an SCST provider is registered, it needs to know what
local ports are available for configuration as targets.
Add a notifier chain that is invoked when any local port
that is added or deleted.
Maintain a global list of local ports and add an
interator function that calls a given function for
every existing local port. This is used when first
loading a provider.
Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
The target provider needs a per-instance lookup table
or other way to lookup sessions quickly without going through
a linear list or serializing too much.
Add a simple void * array indexed by FC-4 type to the fc_lport.
Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Committed-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Add a method for setting handler for incoming exchange.
For multi-sequence exchanges, this allows the target driver
to add a response handler for handling subsequent sequences,
and exchange manager resets.
The new function is called fc_seq_set_resp().
Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Allow FC-4 provider modules to hook into libfc, mostly for targets.
This should allow any FC-4 module to handle PRLI requests and maintain
process-association states.
Each provider registers its ops with libfc and then will be called for
any incoming PRLI for that FC-4 type on any instance. The provider
can decide whether to handle that particular instance using any method
it likes, such as ACLs or other configuration information.
A count is kept of the number of successful PRLIs from the remote port.
Providers are called back with an implicit PRLO when the remote port
is about to be deleted or has been reset.
fc_lport_recv_req() now sends incoming FC-4 requests to FC-4 providers,
and there is a built-in provider always registered for handling
incoming ELS requests.
The call to provider recv() routines uses rcu_read_lock()
so that providers aren't removed during the call. That lock is very
cheap and shouldn't affect any performance on ELS requests.
Providers can rely on the RCU lock to protect a session lookup as well.
Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Fix sparse warning for non-ANSI function declaration.
Declare workqueue structs as static.
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Robert Love <robert.w.love@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Allowing FCoE LOGO followed by CVL in this case prevents
FIP login back to the FCF and then keeps lport offline,
only FIP LOGO and CLV needs to be processed while in
FIP mode, therefore this patch drops FCoE LOGO in FIP mode.
Added fcoe_filter_frames() to filter out above mentioned LOGO
in fcoe rx path along with other existing filtering in code
for bad CRC frames. Adding separate fcoe_filter_frames function
helped with better code indentations and if needed then same
will allow adding more filters at one place in future.
This LOGO drop is added after FCP frames passed up to avoid
any additional checks on fast path for this.
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@suse.de>
vports are not grabbing module references but are
releasing them. This causes the module reference count
to decrement too many times and it wraps around past 0.
The solution is to do a module_put() in
fcoe_interface_release() so that the reference is only
released when the fcoe_interface is released. There is a
one-to-one relationship between the N_Port and the
fcoe_interface, so the module reference will only be
dropped when the N_Port is destroyed
To create symetry in the code this patch moves the
try_module_get() call into fcoe_interface_create(). This
means that only the N_Port will grab a reference to the
module when its corresponding fcoe_interface is created.
This patch also makes it so that the fcoe_interface_create()
routine encodes any error codes in the fcoe_interface
pointer returned. This way its caller, fcoe_create(), can
return an accurate error code.
Signed-off-by: Robert Love <robert.w.love@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Signed-off-by: Venkata Siva Vijayendra Bhamidipati <vbhamidi@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Fix memory leak arising due to incorrect freeing of allocated memory
for vnic stats when unregistering a vnic.
Signed-off-by: Abhijeet Joglekar <abjoglek@cisco.com>
Signed-off-by: Venkata Siva Vijayendra Bhamidipati <vbhamidi@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
If we goto out, then it tries to call kfree_skb() on an ERR_PTR which
will oops. Just return directly.
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
This patch makes it so that we only have one call to
fc_rport_error. This patch does not completely
consolidate return statements, there is still one return
used when not calling fc_rport_error, but alternative
solutions made the code more confusing.
[ Patch modified by Robert Love ]
[ Patch title and commit message edited by Robert Love
to make it more relevant ]
Signed-off-by: Hillf Danton <dhillf@gmail.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Here ticks_left is added to record the result of
wait_for_completion_timeout().
[ Patch title and description edited by Robert Love
to make it more descriptive ]
Signed-off-by: Hillf Danton <dhillf@gmail.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
The fsp's xfer_ddp is used as indication of the exchange id for the DDPed
I/O. We should always initialize it as FC_XID_UNKNOWN for a newly allocated
fsp, otherwise the fsp allocated in fc_fcp, i.e., not from queuecommand like
LUN RESET that is not doing DDP may still think DDP is setup for it since xid
0 is valid and goes on to call fc_fcp_ddp_done() in fc_fcp_resp() from
fc_tm_done(). So, set xfer_ddp as FC_XID_UNKNOWN in fc_fcp_pkt_alloc() now.
Also removes the setting of fsp->lp as it's already done when fsp is allocated.
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@suse.de>
Classify severity of I/O errors for target, nexus, and
transport errors.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Acked-by: Jens Axboe <jaxboe@fusionio.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
DM now has more information about the nature of the underlying storage
failure. Path failure is avoided if a request failed due to a target
error. Instead the target error is immediately passed up the stack.
Discard requests that fail due to non-target errors may now be retried.
Errors restricted to the path will be retried or returned if no
paths are available, irregarding the no_path_retry setting.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Acked-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Instead of just passing 'EIO' for any I/O error we should be
notifying the upper layers with more details about the cause
of this error.
Update the possible I/O errors to:
- ENOLINK: Link failure between host and target
- EIO: Retryable I/O error
- EREMOTEIO: Non-retryable I/O error
- EBADE: I/O error restricted to the I_T_L nexus
'Retryable' in this context means that an I/O error _might_ be
restricted to the I_T_L nexus (vulgo: path), so retrying on another
nexus / path might succeed.
'Non-retryable' in general refers to a target failure, so this
error will always be generated regardless of the I_T_L nexus
it was send on.
I/O errors restricted to the I_T_L nexus might be retried
on another nexus / path, but they should _not_ be queued
if no paths are available.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
The use of blk_execute_rq_nowait() implies __blk_put_request() is needed
in start_stop_endio() rather than blk_put_request() --
blk_finish_request() is called with queue lock already held.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
