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>

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>