When the FCoE sending side becomes congested libfc tries to reduce the
queue depth on the host; however due to the built-in lag before
attempting to ramp down the queue depth _again_ the message log is
flooded with the following message:

	libfc: queue full, reducing can_queue to 512

With this patch the message is printed only once (ie when it's
actually changed).
Signed-off-by: NHannes Reinecke <hare@suse.com>
Reviewed-by: NBart Van Assche <Bart.VanAssche@sandisk.com>
Acked-by: NJohannes Thumshirn <jth@kernel.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

refcount_t type and corresponding API should be used instead of atomic_t
when the variable is used as a reference counter. This allows to avoid
accidental refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: NElena Reshetova <elena.reshetova@intel.com>
Signed-off-by: NHans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NDavid Windsor <dwindsor@gmail.com>
Acked-by: NJohannes Thumshirn <jth@kernel.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The ->seq_start_next callback only ever had one implementation,
so call the function directly and drop the callback.
Signed-off-by: NHannes Reinecke <hare@suse.com>
Acked-by: NJohannes Thumshirn <jth@kernel.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The ->exch_done callback only ever had one implementation,
so we can as well call it directly and drop the callback.
Signed-off-by: NHannes Reinecke <hare@suse.com>
Acked-by: NJohannes Thumshirn <jth@kernel.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The ->seq_exch_abort callback only ever had one implementation,
so we can as well call it directly and drop the callback.
Signed-off-by: NHannes Reinecke <hare@suse.com>
Acked-by: NJohannes Thumshirn <jth@kernel.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The ->seq_send callback only ever had one implementation,
so we can as well call it directly and drop the callback.
Signed-off-by: NHannes Reinecke <hare@suse.com>
Acked-by: NJohannes Thumshirn <jth@kernel.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The ->exch_seq_send callback only ever had one implementation,
so we can call the function directly and drop the callback.
Signed-off-by: NHannes Reinecke <hare@suse.com>
Acked-by: NJohannes Thumshirn <jth@kernel.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The ->lport_reset callback only ever had one implementation,
which already is exported. So remove it and use the function
directly.
Signed-off-by: NHannes Reinecke <hare@suse.com>
Acked-by: NJohannes Thumshirn <jth@kernel.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

When detecting an out-of-order sequence we should be waiting for
E_D_TOV before trying to abort the sequence.
The response might still be stuck in the queue somewhere.
Signed-off-by: NHannes Reinecke <hare@suse.com>
Reviewed-by: NBart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

When we're receiving a timeout we should be checking for queue
full status; if there are still some packets pending we should
be resetting the counter to ensure we're not missing out any
packets which are still queued.
Signed-off-by: NHannes Reinecke <hare@suse.com>
Acked-by: NJohannes Thumshirn <jth@kernel.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

If a sequence should be aborted the exchange might already
be completed (eg if the response is still queued in the rx
queue), so this shouldn't considered as an error.
Signed-off-by: NHannes Reinecke <hare@suse.com>
Acked-by: NJohannes Thumshirn <jth@kernel.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

When a sequence times out we have no idea what happened to the
frame. And we do not know if we will ever receive the frame.
Hence we cannot re-use the xid as we would risk data corruption
if the xid had been re-used and the timed out frame would be
received after that.
So we need to quarantine the xid until the lport is reset.
Yes, I know this will (eventually) deplete the xid pool.
But for now it's the safest method.
Signed-off-by: NHannes Reinecke <hare@suse.com>
Reviewed-by: NBart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

When the queue depth is reduced we should print out the reason
for this; it might be due to a queue full condition.
Signed-off-by: NHannes Reinecke <hare@suse.com>
Acked-by: NJohannes Thumshirn <jth@kernel.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

When a command is aborted it might already have the DID_TIME_OUT
status set, so we shouldn't be overwriting that.
Signed-off-by: NHannes Reinecke <hare@suse.com>
Acked-by: NJohannes Thumshirn <jth@kernel.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

When setting the FCP timeout we need to ensure a lower boundary
for E_D_TOV and R_A_TOV, otherwise we'd be getting spurious I/O
issues due to the fcp timer firing too early.
Signed-off-by: NHannes Reinecke <hare@suse.com>
Acked-by: NJohannes Thumshirn <jth@kernel.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

If a command times out libfc is sending an REC, which also
might fail (due to frames being lost or something).
If no data has been transferred we can simply retry
the command, but the current code sets a state of FC_ERROR,
which then is being translated into DID_ERROR, resulting
in an I/O error.
So to handle this properly we need to set a separate
state FC_TRANS_RESET and mapping it onto DID_SOFT_RETRY.
Signed-off-by: NHannes Reinecke <hare@suse.de>
Acked-by: NJohannes Thumshirn <jth@kernel.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Signed-off-by: NHannes Reinecke <hare@suse.com>
Acked-by: NJohannes Thumshirn <jth@kernel.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Since fc_fcp_cleanup_cmd() can sleep this function must not
be called while holding a spinlock. This patch avoids that
fc_fcp_cleanup_each_cmd() triggers the following bug:

BUG: scheduling while atomic: sg_reset/1512/0x00000202
1 lock held by sg_reset/1512:
 #0:  (&(&fsp->scsi_pkt_lock)->rlock){+.-...}, at: [<ffffffffc0225cd5>] fc_fcp_cleanup_each_cmd.isra.21+0xa5/0x150 [libfc]
Preemption disabled at:[<ffffffffc0225cd5>] fc_fcp_cleanup_each_cmd.isra.21+0xa5/0x150 [libfc]
Call Trace:
 [<ffffffff816c612c>] dump_stack+0x4f/0x7b
 [<ffffffff810828bc>] __schedule_bug+0x6c/0xd0
 [<ffffffff816c87aa>] __schedule+0x71a/0xa10
 [<ffffffff816c8ad2>] schedule+0x32/0x80
 [<ffffffffc0217eac>] fc_seq_set_resp+0xac/0x100 [libfc]
 [<ffffffffc0218b11>] fc_exch_done+0x41/0x60 [libfc]
 [<ffffffffc0225cff>] fc_fcp_cleanup_each_cmd.isra.21+0xcf/0x150 [libfc]
 [<ffffffffc0225f43>] fc_eh_device_reset+0x1c3/0x270 [libfc]
 [<ffffffff814a2cc9>] scsi_try_bus_device_reset+0x29/0x60
 [<ffffffff814a3908>] scsi_ioctl_reset+0x258/0x2d0
 [<ffffffff814a2650>] scsi_ioctl+0x150/0x440
 [<ffffffff814b3a9d>] sd_ioctl+0xad/0x120
 [<ffffffff8132f266>] blkdev_ioctl+0x1b6/0x810
 [<ffffffff811da608>] block_ioctl+0x38/0x40
 [<ffffffff811b4e08>] do_vfs_ioctl+0x2f8/0x530
 [<ffffffff811b50c1>] SyS_ioctl+0x81/0xa0
 [<ffffffff816cf8b2>] system_call_fastpath+0x16/0x7a
Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NVasu Dev <vasu.dev@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Odin.com>

Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: NVasu Dev <vasu.dev@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Odin.com>

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>

Remove the tagged argument from scsi_adjust_queue_depth, and just let it
handle the queue depth.  For most drivers those two are fairly separate,
given that most modern drivers don't care about the SCSI "tagged" status
of a command at all, and many old drivers allow queuing of multiple
untagged commands in the driver.

Instead we start out with the ->simple_tags flag set before calling
->slave_configure, which is how all drivers actually looking at
->simple_tags except for one worke anyway.  The one other case looks
broken, but I've kept the behavior as-is for now.

Except for that we only change ->simple_tags from the ->change_queue_type,
and when rejecting a tag message in a single driver, so keeping this
churn out of scsi_adjust_queue_depth is a clear win.

Now that the usage of scsi_adjust_queue_depth is more obvious we can
also remove all the trivial instances in ->slave_alloc or ->slave_configure
that just set it to the cmd_per_lun default.
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: NMartin K. Petersen <martin.petersen@oracle.com>

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>

This patch avoids that the FCoE initiator sends a REC message after
having received a SCSI response with non-zero status and non-zero
DATA IN buffer length.
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>

Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Currently fc_fcp_timeout doesn't check FC_RP_FLAGS_REC_SUPPORTED
flag first, this prevents REC request ever going out at all
to the target having REC support. So this patches fixes the
fc_fcp_timeout by checking FC_RP_FLAGS_REC_SUPPORTED flag first.

The changed order won't cause any issue during clearing
FC_RP_FLAGS_REC_SUPPORTED on failed IO with target not supporting
FC_RP_FLAGS_REC_SUPPORTED, since retry on failed IO would succeed.
Signed-off-by: NVasu Dev <vasu.dev@intel.com>
Tested-by: NRoss Brattain <ross.b.brattain@intel.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>

In LUN RESET testing involving NetApp targets, it is observed that LUN
RESET is failing. The fc_fcp_resp() is not completing the completion
for the LUN RESET task since fc_fcp_resp assumes that the FCP_RSP_INFO
is 8 bytes with the 4 byte reserved field, where in case of NetApp targets
the FCP_RSP to LUN RESET only has 4 bytes of FCP_RSP_INFO. This leads
fc_fcp_resp to error out w/o completing the task completion, eventually
causing LUN RESET to be escalated to host reset, which is not very nice.

Per FCP-3 r04, clause 9.5.15 and Table 23, the FCP_RSP_INFO field can be either
4 bytes or 8 bytes, with the last 4 bytes as "Reserved (if any)". Therefore it
is valid to have 4 bytes FCP_RSP_INFO like some of the NetApp targets behave.
Fixing this by validating the FCP_RSP_INFO against both the two spec allowed
length.
Reported-by: NFrank Zhang <frank_1.zhang@intel.com>
Signed-off-by: NYi Zou <yi.zou@intel.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>

This is exposed in the case the FCP_DATA frames somehow got lost and fc_fcp got
the FCP_RSP, in fc_fcp_recv_resp(), since xfer_len is less than the expected_len
it resets the the timer to wait to 2 more jiffies in case the data frames are
already queued locally. However, for target does not support REC, it would just
send RJT w/ ELS_RJT_UNSUP. The rec response handler thus only clears the rport
flag for not doing REC later, but does not do fcp_io_complete() on the
associated fsp.

The fix is just check status of FCP_RSP being received already, i.e. using the
FC_SRB_RCV_STATUS flag, in fc_fcp_timeout before start sending REC. We should
have waited long enough if there is truely data frames queued locally.
Signed-off-by: NYi Zou <yi.zou@intel.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>

Adds stats to track FCP pkt and frame alloc
failure.
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>
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>

Signed-off-by: NCong Wang <amwang@redhat.com>

This allows us to use scsilun_to_int without an ugly cast.

Fix up places that use scsilun_to_int on fcp->fc_lun accordingly.

In fc target, this leaves ft_cmd.lun unused, so remove it.
Signed-off-by: NAndy Grover <agrover@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Kiran Patil <kiran.patil@intel.com>
Cc: James Bottomley <JBottomley@Parallels.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

The fcp timer is already initialized when it gets allocated.
Signed-off-by: NYi Zou <yi.zou@intel.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>

Re-arrange its fields to avoid padding and have better
cacheline alignments.

Removed not used start_time, end_time and last_pkt_time
fields.

This all reduced this struct size to 448 from 480 and
that also reduced one cacheline on x86_64 beside
eliminating 8 pads. However kept logical fields together.
Signed-off-by: NVasu Dev <vasu.dev@intel.com>
Tested-by: NRoss Brattain <ross.b.brattain@intel.com>
Signed-off-by: NYi Zou <yi.zou@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Call fc_block_scsi_eh() in all fcoe eh to blocks
the scsi_eh thread for blocked rports.
Signed-off-by: NVasu Dev <vasu.dev@intel.com>
Tested-by: NRoss Brattain <ross.b.brattain@intel.com>
Reviewed-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>

fc_queuecommand() allocates an FCP packet for each SCSI command and sends
it out on the wire. In the process it stores the reference to the FCP packet
in the scsi_cmnd structure.
Now, in case under stress testing the libfc exchange layer runs out of
exchanges the fc_queuecommand() may not be able to send out commands out on
the wire. In such a scenario if there is an error in sending the FCP packet
out the wire; fc_queuecommand() deletes the FCP packet from internal queue,
releases the FCP packet and returns a SCSI_MLQUEUE_HOST_BUSY status to the
scsi-ml. But, the reference to the FCP packet set in the scsi_cmnd is not
removed from the scsi_cmnd in this code path.

This might lead to a crash under stress testing where the scsi_cmnd failed by
fc_queuecommand() comes up to fc_eh_abort() via scsi eh thread. fc_eh_abort()
will get reference to the FCP packet to be aborted from the scsi_cmnd for
further FCP abort related processing and then try to release the FCP packet
that has already been released.

This patch removes the FCP packet reference from the scsi_cmnd before returning
back from fc_queuecommand() in case of an error in sending out the FCP packet.
Signed-off-by: NNeerav Parikh <Neerav.Parikh@intel.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>

The variable on stack, namely cdb_op, is not used but removed.

[ Patch reworked by Robert Love due to invalid patch format ]
Signed-off-by: NHillf Danton <dhillf@gmail.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

One change is to cleanup typo in comment for fc_fcp_recv(), another corrects
the misleading comment for fc_fcp_abts_resp().

[ Patch reworked by Robert Love due to invalid patch format ]
Signed-off-by: NHillf Danton <dhillf@gmail.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Though defined, FC_MAX_ERROR_CNT is not used. It is used now for CRC error in
the path of receiving FCP frame.
Signed-off-by: NHillf Danton <dhillf@gmail.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>