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>

Currently, when seq_send() fails in fc_fcp_send_data(),
fc_fcp_retry_cmd() would complete this failed I/O directly and let
scsi-ml retry. However, target side is not notified which may hang the
target. Instead, we should just bail out from from fc_fcp_send_data
and let scsi-ml times it out and aborts this I/O instead.
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>

In this case fsp was freed before error handler was invoked,
this is fixed by having SRR fsp reference freed by exch
destructor so that fsp will be always held until it exch
is freed.

Also don't reset fsp->recov_seq since this is needed by
SRR error handler to do exch done.
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>
Signed-off-by: NJames Bottomley <jbottomley@parallels.com>

In case frame_send() fails, make sure to let the underlying HW release the DDP
context that has already been set up before calling frame_send().
Signed-off-by: NYi Zou <yi.zou@intel.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <jbottomley@parallels.com>

Added REC_TOV_CONST intent was to have rec tov as e_d_tov + 1s
but currently it is e_d_tov + 1ms since e_d_tov is stored in ms
unit.

Also returned rec tov by get_fsp_rec_tov is in ms and this ms tov
is used as-is with fc_fcp_timer_set expecting jiffies tov.

Fixed this by having get_fsp_rec_tov return rec tov in jiffies
as e_d_tov + 1s and then use jiffies tov w/ fc_fcp_timer_set.

Also some cleanup, no need to cache get_fsp_rec_tov return value
in local rec_tov at various places.
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>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

The host_lock is still used to protect the can_queue
value in the Scsi_Host, but it doesn't need to be held
and released by each caller. This patch moves the lock
usage into the fc_fcp_can_queue_ramp_up and
fc_fcp_can_queue_ramp_down routines.
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Tested-by: NRoss Brattain <ross.b.brattain@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

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

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: NRobert Love <robert.w.love@intel.com>
Tested-by: NRoss Brattain <ross.b.brattain@intel.com>
Reviewed-by: NNicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

Fix sparse warning for non-ANSI function declaration.
Declare workqueue structs as static.
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Cc:	Robert Love <robert.w.love@intel.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames 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: NDan Carpenter <error27@gmail.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames 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: NHillf Danton <dhillf@gmail.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames 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: NYi Zou <yi.zou@intel.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

The statistics for InputMegabytes and OutputMegabytes are
misnamed.  They're accumulating bytes, not megabytes.

The statistic returned via /sys must be in megabytes, however,
which is what the HBA-API wants.  The FCP code needs to accumulate
it in bytes and then divide by 1,000,000 (not 2^20) before it
presented via sysfs.

This affects fcoe.ko only, not fnic.  The fnic driver
correctly by accumulating bytes and then converts to megabytes.

I checked that libhbalinux is using the /sys file directly without
conversion.

BTW, qla2xxx does divide by 2^20, which I'm not fixing here.
Signed-off-by: NJoe Eykholt <jeykholt@cisco.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

Frame should be freed in fc_tm_done, this is an updated patch on the one
initially submitted by Hillf Danton.
Signed-off-by: NHillf Danton <dhillf@gmail.com>
Signed-off-by: NYi Zou <yi.zou@intel.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

The timeout for the exchange carrying REC itself is 2 * R_A_TOV_els.
Signed-off-by: NYi Zou <yi.zou@intel.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

Do not call fc_io_compl() on fsp w/o any scsi_cmnd, e.g., lun reset is built
inside fc_fcp, not from a scsi command from queuecommnd from scsi-ml, so in
in case target is buggy that is invalid flags in the FCP_RSP, as we have seen
in some SAN Blaze target where all bits in flags are 0, we do not want to call
io_compl on this fsp.

[ Comment block added by Robert Love ]
Signed-off-by: NYi Zou <yi.zou@intel.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

We can easily remove the tgt_flags from fc_fcp_pkt struct
and use rpriv->tgt_flags directly where needed.
Signed-off-by: NJohn Fastabend <john.r.fastabend@intel.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

Use the rport value for rec_tov for timeout values when
sending fcp commands. Currently, defaults are being used
which may or may not match the advertised values.

The default may cause i/o to timeout on networks that
set this value larger then the default value. To make
the timeout more configurable in the non-REC mode we
remove the FC_SCSI_ER_TIMEOUT completely allowing the
scsi-ml to do the timeout. This removes an unneeded
timer and allows the i/o timeout to be configured
using the scsi-ml knobs.
Signed-off-by: NJohn Fastabend <john.r.fastabend@intel.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

The fcp packet recovery handler fc_fcp_recover() is called
when errors occurr in a fcp session. Currently it is
generically setting the status code to FC_CMD_RECOVERY for
all error types. This results in DID_BUS_BUSY errors
being returned to the scsi-ml.

DID_BUS_BUSY errors indicate "BUS stayed busy through time
out period" according to scsi.h. Many of the error reported
by fc_rcp_recovery() are pkt errors. Here we update
fc_fcp_recovery to use better host byte codes.

With certain FAST FAIL flags set DID_BUS_BUSY and DID_ERROR
will have different behaviors this was causing dm multipath
to fail quickly in some cases where a retry would be a
better action.
Signed-off-by: NJohn Fastabend <john.r.fastabend@intel.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

There seems accumulation needed.
Signed-off-by: NHillf Danton <dhillf@gmail.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

The error handler grabs the si->scsi_queue_lock, but
in the case where the fsp pointer is NULL it releases
the scsi_host lock. This can lead to a variety of
system hangs depending on which is used first- the
scsi_host lock or the scsi_queue_lock.

This patch simply unlocks the correct lock when fcp
is NULL.
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Tested-by: NRoss Brattain <ross.b.brattain@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

Move the mid-layer's ->queuecommand() invocation from being locked
with the host lock to being unlocked to facilitate speeding up the
critical path for drivers who don't need this lock taken anyway.

The patch below presents a simple SCSI host lock push-down as an
equivalent transformation.  No locking or other behavior should change
with this patch.  All existing bugs and locking orders are preserved.

Additionally, add one parameter to queuecommand,
	struct Scsi_Host *
and remove one parameter from queuecommand,
	void (*done)(struct scsi_cmnd *)

Scsi_Host* is a convenient pointer that most host drivers need anyway,
and 'done' is redundant to struct scsi_cmnd->scsi_done.

Minimal code disturbance was attempted with this change.  Most drivers
needed only two one-line modifications for their host lock push-down.
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>
Acked-by: NJames Bottomley <James.Bottomley@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

"gadget", "through", "command", "maintain", "maintain", "controller", "address",
"between", "initiali[zs]e", "instead", "function", "select", "already",
"equal", "access", "management", "hierarchy", "registration", "interest",
"relative", "memory", "offset", "already",
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

It is unlikely but in case if it hits then it would cause panic
due to null cmd ptr, so far only one instance seen recently with
ESX though this was introduced long ago with this commit:-

commit c1ecb90a
Author: Chris Leech <christopher.leech@intel.com>
Date:   Thu Dec 10 09:59:26 2009 -0800
[SCSI] libfc: reduce hold time on SCSI host lock

Currently fsp->cmd is set to NULL w/o scsi_queue_lock before
dequeuing from scsi_pkt_queue and that could cause NULL
fsp->cmd in fc_fcp_cleanup_each_cmd for cmd completing
with fsp->cmd = NULL after fc_fcp_cleanup_each_cmd taken
reference. No need to set fsp->cmd to NULL as this is also
protected by fc_fcp_lock_pkt(), for above race the
fc_fcp_lock_pkt() in fc_fcp_cleanup_each_cmd() will fail
as that cmd is  already done.

Mike mentioned same issue at
http://www.open-fcoe.org/pipermail/devel/2010-September/010533.html

Similarly moved sc_cmd->SCp.ptr = NULL under scsi_queue_lock so
that scsi abort error handler won't abort on completed cmds.
Signed-off-by: NVasu Dev <vasu.dev@intel.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

This is per Mile Christie feedback since in this case IO
could get retried for tape devices and therefore DID_REQUEUE
cannot be used, more details in this thread.

http://marc.info/?l=linux-scsi&m=127970522630136&w=2Signed-off-by: NVasu Dev <vasu.dev@intel.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

The rport port state and flags are set under the host lock,
so this patch calls fc_remote_port_chkready with the host lock
held like is also done in the other fc drivers.
Signed-off-by: NMike Christie <michaelc@cs.wisc.edu>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

Add functions to fill in an FC header given a request header.
These reduces code lines in fc_lport and fc_rport and works
without an exchange/sequence assigned.

fc_fill_reply_hdr() fills a header for a final reply frame.

fc_fill_hdr() which is similar but allows specifying the
f_ctl parameter.

Add defines for F_CTL values FC_FCTL_REQ and FC_FCTL_RESP.
These can be used for most request and response sequences.

v2 of patch adds a line to copy the frame encapsulation
info from the received frame.
Signed-off-by: NJoe Eykholt <jeykholt@cisco.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

In this case, sync IO fails with EIO(5) errors as:-

"Thread:1 System call error:5 - Input/output error (::pwrite() failed)".

This is due to IO time out while libfc doing link down processing
to block all rports and if timed out IO was at last retry
attempt then it fails to user with EIO error followed by
these log messages.

[77848.612169] host2: rport bf0015: Delete port
[77848.612221] host2: rport e10aef: work delete
[77848.612232] host2: rport e10002: work event 3
[77848.612422] sd 2:0:1:1: [sdi] Unhandled error code
[77848.612426] sd 2:0:1:1: [sdi] Result: hostbyte=DID_ERROR
driverbyte=DRIVER_OK
[77848.612431] sd 2:0:1:1: [sdi] CDB: Write(10): 2a 00 00 00 11 20 00 00 20 00
[77848.612445] end_request: I/O error, dev sdi, sector 4384
[77848.612553] sd 2:0:1:2: [sdj] Unhandled error code

To fix these EIO errors, such timed out incomplete IOs needs
to be re-queued without counting retry attempt and this patch
does that using DID_REQUEUE scsi code.
Signed-off-by: NVasu Dev <vasu.dev@intel.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

This is exposed by a mpio test using EMC CLARiiON targets when LUN
tresspassing happens, the burst length from the XFER_READY for the
MODE SELECT(10) is 19 bytes, much smaller than FC_MIN_MAX_PAYLOAD as
256 bytes. This patch removes the related two WARN_ON()s.
Signed-off-by: NYi Zou <yi.zou@intel.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

lport state is enum not bit mask.
Signed-off-by: NYi Zou <yi.zou@intel.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

This patch creates a port_id member in struct fc_lport.
This allows libfc to just deal with fc_lport instances
instead of calling into the fc_host to get the port_id.

This change helps in only using symbols necessary for
operation from the libfc structures. libfc still needs
to change the fc_host_port_id() if the port_id changes
so the presentation layer (scsi_transport_fc) can provide
the user with the correct value, but libfc shouldn't
rely on the presentation layer for operational values.
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

Most of the prints of fabric IDs were specified as %6x, which will not
print any leading 0s.  It's nice to see leading 0s for identifiers
like this, which are a fixed length.  This patch sets the precision
modifier as well, making the specifier %6.6x, which forces the
printing of leading 0s.
Signed-off-by: NChris Leech <christopher.leech@intel.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

fc_fcp_resp is assuming when FCP_SNS_LEN_VAL is set, the FCP_RSP_LEN_VAL
is not, which is not true. This leads to not copying the sense data and
error out a valid FCP_RSP.
Signed-off-by: NYi Zou <yi.zou@intel.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

When the kernel is configured for preemption, using smp_processor_id()
when preemption is enabled causes a warning backtrace and is wrong
since we could move off of that CPU as soon as we get the ID,
and we would be referencing the wrong CPU, and possibly an invalid one
if it could be hotswapped out.

Remove the fc_lport_get_stats() function and explicitly use per_cpu_ptr()
to get the statistics.  Where preemption has been disabled by holding
a _bh lock continue to use smp_processor_id(), but otherwise use
get_cpu()/put_cpu().

In fcoe_recv_frame() also changed the cases where we return in the
middle to do a goto to the code which bumps ErrorFrames and does
a put_cpu().  Two of these cases didn't bump ErrorFrames before, but
doing so is harmless because they "can't happen", due to prior length
checks.

Also rearranged code in fcoe_recv_frame() to have only one call to
fc_exch_recv().  It's just as efficient and saves a call to put_cpu().

In fc_fcp.c, adjusted a FIXME comment for code which doesn't need fixing.
Signed-off-by: NJoe Eykholt <jeykholt@cisco.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

DID_ERROR cases can be ambigouos. Debugging FCP error cases
will be much easier if we have debug statements when we hit
these error conditions.

This patch simply adds debug messages using the FC_FCP_DBG
macro when we return DID_ERROR to SCSI. This way if a DID_ERROR
is reproducible turning on debug_logging will give a clue
to developers as to what the problem might be.
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>