History log of /drivers/scsi/libfc/fc_fcp.c
Revision Date Author Comments (<<< Hide modified files) (Show modified files >>>)
76ffe8a3f766358a0ade543153625b3e4e66159d 14-Jan-2012 Yi Zou <yi.zou@intel.com> [SCSI] libfc: remove redundant timer init for fcp

The fcp timer is already initialized when it gets allocated.

Signed-off-by: Yi Zou <yi.zou@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
/drivers/scsi/libfc/fc_fcp.c
ec7ae517537ae5c7b0b2cd7f562dfa3e7a05b954 29-Oct-2011 Linus Torvalds <torvalds@linux-foundation.org> Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6

* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6: (204 commits)
[SCSI] qla4xxx: export address/port of connection (fix udev disk names)
[SCSI] ipr: Fix BUG on adapter dump timeout
[SCSI] megaraid_sas: Fix instance access in megasas_reset_timer
[SCSI] hpsa: change confusing message to be more clear
[SCSI] iscsi class: fix vlan configuration
[SCSI] qla4xxx: fix data alignment and use nl helpers
[SCSI] iscsi class: fix link local mispelling
[SCSI] iscsi class: Replace iscsi_get_next_target_id with IDA
[SCSI] aacraid: use lower snprintf() limit
[SCSI] lpfc 8.3.27: Change driver version to 8.3.27
[SCSI] lpfc 8.3.27: T10 additions for SLI4
[SCSI] lpfc 8.3.27: Fix queue allocation failure recovery
[SCSI] lpfc 8.3.27: Change algorithm for getting physical port name
[SCSI] lpfc 8.3.27: Changed worst case mailbox timeout
[SCSI] lpfc 8.3.27: Miscellanous logic and interface fixes
[SCSI] megaraid_sas: Changelog and version update
[SCSI] megaraid_sas: Add driver workaround for PERC5/1068 kdump kernel panic
[SCSI] megaraid_sas: Add multiple MSI-X vector/multiple reply queue support
[SCSI] megaraid_sas: Add support for MegaRAID 9360/9380 12GB/s controllers
[SCSI] megaraid_sas: Clear FUSION_IN_RESET before enabling interrupts
...
ed26cfece6177310ad8f5896651a3187ce02711c 28-Sep-2011 Vasu Dev <vasu.dev@intel.com> [SCSI] libfc: cache align struct fc_fcp_pkt fields

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: Vasu Dev <vasu.dev@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Yi Zou <yi.zou@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
/drivers/scsi/libfc/fc_fcp.c
21cc0bd3a9e524b44a4f0ff05ac612aa0ff1a26e 25-Aug-2011 Vasu Dev <vasu.dev@intel.com> [SCSI] libfc: block SCSI eh thread for blocked rports

Call fc_block_scsi_eh() in all fcoe eh to blocks
the scsi_eh thread for blocked rports.

Signed-off-by: Vasu Dev <vasu.dev@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Reviewed-by: Yi Zou <yi.zou@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
/drivers/scsi/libfc/fc_fcp.c
c9d24a76184b3ecbedc66d45f840c3dfd921f12b 28-Jul-2011 Neerav Parikh <Neerav.Parikh@intel.com> [SCSI] libfc: Remove the reference to FCP packet from scsi_cmnd in case of error

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: Neerav Parikh <Neerav.Parikh@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
/drivers/scsi/libfc/fc_fcp.c
85982127273be0474e9505c0aac35973a0a013f8 28-Jul-2011 Hillf Danton <dhillf@gmail.com> [SCSI] libfc: cleanup sending SRR request

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: Hillf Danton <dhillf@gmail.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
/drivers/scsi/libfc/fc_fcp.c
547fb12b7a1c8de6bb57a68553f2319430a3541a 28-Jul-2011 Hillf Danton <dhillf@gmail.com> [SCSI] libfc: two minor changes in comments

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: Hillf Danton <dhillf@gmail.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
/drivers/scsi/libfc/fc_fcp.c
688fd36427050a87b19f6830c882ee77bb851ecf 28-Jul-2011 Hillf Danton <dhillf@gmail.com> [SCSI] libfc: use FC_MAX_ERROR_CNT

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: Hillf Danton <dhillf@gmail.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
/drivers/scsi/libfc/fc_fcp.c
8467b96c035a45418c5db2619f396b7131b4efa8 17-May-2011 Yi Zou <yi.zou@intel.com> [SCSI] libfc: do not immediately retry the cmd when seq_send fails in fc_fcp_send_data

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: Yi Zou <yi.zou@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <jbottomley@parallels.com>
/drivers/scsi/libfc/fc_fcp.c
0a219edb263ef93e4fd7a83804bea667e72a7bfa 17-May-2011 Vasu Dev <vasu.dev@intel.com> [SCSI] libfc: fix race in SRR response

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: Vasu Dev <vasu.dev@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <jbottomley@parallels.com>
/drivers/scsi/libfc/fc_fcp.c
6a716a8535ea8ed7676cea1e122f1c3d02e55b6b 17-May-2011 Yi Zou <yi.zou@intel.com> [SCSI] libfc: release DDP context if frame_send() fails

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: Yi Zou <yi.zou@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <jbottomley@parallels.com>
/drivers/scsi/libfc/fc_fcp.c
f2817ec2e0faece03959888050730ed35e5f2bd2 02-Apr-2011 Vasu Dev <vasu.dev@intel.com> [SCSI] libfc: rec tov value and REC_TOV_CONST units usages is incorrect

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: Vasu Dev <vasu.dev@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
/drivers/scsi/libfc/fc_fcp.c
9c8cce8e416b3286720379b5efa1c7fa81b2ec36 02-Apr-2011 Robert Love <robert.w.love@intel.com> [SCSI] libfc: Move host_lock usage into ramp_up/down routines

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: 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>
/drivers/scsi/libfc/fc_fcp.c
25985edcedea6396277003854657b5f3cb31a628 31-Mar-2011 Lucas De Marchi <lucas.demarchi@profusion.mobi> Fix common misspellings

Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
/drivers/scsi/libfc/fc_fcp.c
04885b16a1ec86b4670702b99a81805e66bf9f30 29-Jan-2011 Robert Love <robert.w.love@intel.com> [SCSI] libfc: Remove usage of the Scsi_Host's host_lock

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>
/drivers/scsi/libfc/fc_fcp.c
55204909bb687c997d5601e9f24a25cf9e915d78 29-Jan-2011 Randy Dunlap <randy.dunlap@oracle.com> [SCSI] libfc: fix sparse static and non-ANSI warnings

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>
/drivers/scsi/libfc/fc_fcp.c
e4a9a98289606392f2b1b24b4ca4e29154ec4d15 29-Jan-2011 Dan Carpenter <error27@gmail.com> [SCSI] libfc:prevent dereferencing ERR_PTR in fc_tm_done()

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>
/drivers/scsi/libfc/fc_fcp.c
fa79dbdbdd166025b5835bddaff152bb57c4440a 29-Jan-2011 Hillf Danton <dhillf@gmail.com> [SCSI] libfc: Return a valid return code in fc_fcp_pkt_abort()

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>
/drivers/scsi/libfc/fc_fcp.c
f56635a8695f6b4fccf546cb2d5cf246d1892a0f 29-Jan-2011 Yi Zou <yi.zou@intel.com> [SCSI] libfc: always initialize the FCoE DDP exchange id for fsp as FC_XID_UNKNOWN

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>
/drivers/scsi/libfc/fc_fcp.c
008d23e4852d78bb2618f2035f8b2110b6a6b968 13-Jan-2011 Linus Torvalds <torvalds@linux-foundation.org> Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (43 commits)
Documentation/trace/events.txt: Remove obsolete sched_signal_send.
writeback: fix global_dirty_limits comment runtime -> real-time
ppc: fix comment typo singal -> signal
drivers: fix comment typo diable -> disable.
m68k: fix comment typo diable -> disable.
wireless: comment typo fix diable -> disable.
media: comment typo fix diable -> disable.
remove doc for obsolete dynamic-printk kernel-parameter
remove extraneous 'is' from Documentation/iostats.txt
Fix spelling milisec -> ms in snd_ps3 module parameter description
Fix spelling mistakes in comments
Revert conflicting V4L changes
i7core_edac: fix typos in comments
mm/rmap.c: fix comment
sound, ca0106: Fix assignment to 'channel'.
hrtimer: fix a typo in comment
init/Kconfig: fix typo
anon_inodes: fix wrong function name in comment
fix comment typos concerning "consistent"
poll: fix a typo in comment
...

Fix up trivial conflicts in:
- drivers/net/wireless/iwlwifi/iwl-core.c (moved to iwl-legacy.c)
- fs/ext4/ext4.h

Also fix missed 'diabled' typo in drivers/net/bnx2x/bnx2x.h while at it.
4b7bd364700d9ac8372eff48832062b936d0793b 22-Dec-2010 Jiri Kosina <jkosina@suse.cz> Merge branch 'master' into for-next

Conflicts:
MAINTAINERS
arch/arm/mach-omap2/pm24xx.c
drivers/scsi/bfa/bfa_fcpim.c

Needed to update to apply fixes for which the old branch was too
outdated.
5f0e385fdafb7d6c8ded6464fa6421c735d96caf 01-Dec-2010 Joe Eykholt <jeykholt@cisco.com> [SCSI] libfc: fix statistics for FCP input/output megabytes

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: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
/drivers/scsi/libfc/fc_fcp.c
b5fe5e953c65cd0ec4e9ffd001072700e5b89317 01-Dec-2010 Yi Zou <yi.zou@intel.com> [SCSI] libfc: fix fc_tm_done not freeing the allocated fsp pkt

Frame should be freed in fc_tm_done, this is an updated patch on the one
initially submitted by Hillf Danton.

Signed-off-by: Hillf Danton <dhillf@gmail.com>
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>
/drivers/scsi/libfc/fc_fcp.c
3a91090fe0df10091c5612db8528ee7a822ab83d 01-Dec-2010 Yi Zou <yi.zou@intel.com> [SCSI] libfc: the timeout for the REC itself is 2 * R_A_TOV_els

The timeout for the exchange carrying REC itself is 2 * R_A_TOV_els.

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>
/drivers/scsi/libfc/fc_fcp.c
d889b30a9196c453120ca54323fe80acb4c27b94 01-Dec-2010 Yi Zou <yi.zou@intel.com> [SCSI] libfc: do not fc_io_compl on fsp w/o any scsi_cmnd associated

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: 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>
/drivers/scsi/libfc/fc_fcp.c
05fee645e96e732a79ad083cab8ddd4efd108e2c 01-Dec-2010 john fastabend <john.r.fastabend@intel.com> [SCSI] libfc: remove tgt_flags from fc_fcp_pkt struct

We can easily remove the tgt_flags from fc_fcp_pkt struct
and use rpriv->tgt_flags directly where needed.

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
/drivers/scsi/libfc/fc_fcp.c
e0883a3c3e7766b390971a49bf728004816c9520 01-Dec-2010 john fastabend <john.r.fastabend@intel.com> [SCSI] libfc: use rport timeout values for fcp recovery

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: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
/drivers/scsi/libfc/fc_fcp.c
ac17ea8d7d45d0495316edff13faa0dfd6bb2225 01-Dec-2010 john fastabend <john.r.fastabend@intel.com> [SCSI] libfc: incorrect scsi host byte codes returned to scsi-ml

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: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
/drivers/scsi/libfc/fc_fcp.c
e90ff5ef0aab1d40f0e92a44d66f8d45a20d8c95 01-Dec-2010 Hillf Danton <dhillf@gmail.com> [SCSI] libfc: fix stats computation in fc_queuecommand()

There seems accumulation needed.

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>
/drivers/scsi/libfc/fc_fcp.c
3c2c3bf23cbef8eed6cf815715d0bece5cb7b5ec 01-Dec-2010 Robert Love <robert.w.love@intel.com> [SCSI] libfc: Fix incorrect locking and unlocking in FCP

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: 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>
/drivers/scsi/libfc/fc_fcp.c
f281233d3eba15fb225d21ae2e228fd4553d824a 16-Nov-2010 Jeff Garzik <jeff@garzik.org> SCSI host lock push-down

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: Jeff Garzik <jgarzik@redhat.com>
Acked-by: James Bottomley <James.Bottomley@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
/drivers/scsi/libfc/fc_fcp.c
b595076a180a56d1bb170e6eceda6eb9d76f4cd3 01-Nov-2010 Uwe Kleine-König <u.kleine-koenig@pengutronix.de> tree-wide: fix comment/printk typos

"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: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
/drivers/scsi/libfc/fc_fcp.c
8b7ac2bb07bbadb0636f21f51564e6d363bb6d20 09-Oct-2010 Vasu Dev <vasu.dev@intel.com> [SCSI] libfc: possible race could panic system due to NULL fsp->cmd

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 c1ecb90a66c5afc7cc5c9349f9c3714eef4a5cfb
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: 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>
/drivers/scsi/libfc/fc_fcp.c
75eee7252466342e0dfa6675106bcd3955090f67 09-Oct-2010 Vasu Dev <vasu.dev@intel.com> [SCSI] libfc: use DID_TRANSPORT_DISRUPTED while lport not ready

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=2

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>
/drivers/scsi/libfc/fc_fcp.c
be948fc30dabc347e4fba4daf4da9fd83d2abf49 02-Aug-2010 Mike Christie <michaelc@cs.wisc.edu> [SCSI] libfc: call fc_remote_port_chkready under the host lock.

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: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
/drivers/scsi/libfc/fc_fcp.c
24f089e2f2c800f88039e9d536d558ec6e349fad 21-Jul-2010 Joe Eykholt <jeykholt@cisco.com> [SCSI] libfc: add fc_fill_reply_hdr() and fc_fill_hdr()

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: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
/drivers/scsi/libfc/fc_fcp.c
e0d93c5bc47ae270ea38192c9a49f660e0406060 21-Jul-2010 Vasu Dev <vasu.dev@intel.com> [SCSI] libfc: IO errors on link down due to cable unplug

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: 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>
/drivers/scsi/libfc/fc_fcp.c
ba402804ac2447ad41f4919603bf3e6f6db63110 21-Jul-2010 Yi Zou <yi.zou@intel.com> [SCSI] libfc: fix slowpath error from WARN_ON in fc_fcp_send_data

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: 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>
/drivers/scsi/libfc/fc_fcp.c
1c4bfe6305215f09f3e80a14a824e4ae45b2c7ed 12-Jun-2010 Yi Zou <yi.zou@intel.com> [SCSI] libfc: lport state is enum not bit mask

lport state is enum not bit mask.

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>
/drivers/scsi/libfc/fc_fcp.c
7b2787ec15b9d1c2f716da61b0eec21a3f5e6520 08-May-2010 Robert Love <robert.w.love@intel.com> [SCSI] libfc: Move the port_id into lport

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: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
/drivers/scsi/libfc/fc_fcp.c
ce8b5df04292e93a117d9f863af206245bf61271 09-Apr-2010 Chris Leech <christopher.leech@intel.com> [SCSI] libfc: set both precision and field with when printing FC IDs

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: Chris Leech <christopher.leech@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
/drivers/scsi/libfc/fc_fcp.c
63ac4bbffb40f2cb3bc7e8b11bac47598813ea13 09-Apr-2010 Yi Zou <yi.zou@intel.com> [SCSI] libfc: bug in erroring out upon FCP_RSP_LEN_VAL in fc_fcp_resp

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: 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>
/drivers/scsi/libfc/fc_fcp.c
f018b73af6db4f330ad5da9ac53997a699c30c42 13-Mar-2010 Joe Eykholt <jeykholt@cisco.com> [SCSI] libfc, libfcoe, fcoe: use smp_processor_id() only when preempt disabled

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: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
/drivers/scsi/libfc/fc_fcp.c
b3ef990c1514859bffae221b9e82e46a38f1e7bf 13-Mar-2010 Robert Love <robert.w.love@intel.com> [SCSI] libfc: Add debug statements when fc_fcp returns DID_ERROR to scsi-ml

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: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
/drivers/scsi/libfc/fc_fcp.c
5c12c418e905aac2826bb70f947648944c079ed9 13-Mar-2010 Vasu Dev <vasu.dev@intel.com> [SCSI] libfc: fix fcp pkt recovery in fc_fcp_recv_data

Currently fc_fcp_recv_data calls fc_fcp_retry_cmd to
retry failed IO but in this case tgt is still sending
data frames, therefore exchange needs to be aborted
first before initiating retry. So this patch fixes
this by aborting exchange first then have retry.

Renames fc_timeout_error to fc_fcp_recovery since
fc_timeout_error is already called from several other
places beside from fcp timeout handler and then
used fc_fcp_recovery for abort & retry from
fc_fcp_recv_data, this rename also required renaming
FC_CMD_TIME_OUT status to FC_CMD_RECOVERY to be
consistent with new fc_fcp_recovery.

Data frames are not expected for an DDPed exchange and
potentially it could be tampered data frame, so does
recovery in this case by calling fc_fcp_recovery.

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>
/drivers/scsi/libfc/fc_fcp.c
5a0e3ad6af8660be21ca98a971cd00f331318c05 24-Mar-2010 Tejun Heo <tj@kernel.org> include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.

2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).

* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
/drivers/scsi/libfc/fc_fcp.c
318ae2edc3b29216abd8a2510f3f80b764f06858 08-Mar-2010 Jiri Kosina <jkosina@suse.cz> Merge branch 'for-next' into for-linus

Conflicts:
Documentation/filesystems/proc.txt
arch/arm/mach-u300/include/mach/debug-macro.S
drivers/net/qlge/qlge_ethtool.c
drivers/net/qlge/qlge_main.c
drivers/net/typhoon.c
10897ae71dd6e205969726e0f817f3327ef32f83 21-Jan-2010 Vasu Dev <vasu.dev@intel.com> [SCSI] libfc: call ddp setup for only FCP reads to avoid accessing junk fsp pointer

Adds check to call fc_fcp_ddp_setup for only FCP read cmds to avoid
accessing junk fsp pointer at least in ESX since non FCP frame had
junk fsp value, though fsp is implicitly initialized to null
by __alloc_skb but with this patch no more relying on fsp
initialized to null value and hitting junk fsp ptr access.

Removes fsp pointer checking in fc_fcp_ddp_setup as this is not
needed any more since its only caller for FCP read will always
have a valid fsp.

Reported by: Frank Zhang <frank_1.zhang@intel.com>
Reported by: Rob Love <robert.w.love@intel.com>
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>
/drivers/scsi/libfc/fc_fcp.c
3ad2f3fbb961429d2aa627465ae4829758bc7e07 03-Feb-2010 Daniel Mack <daniel@caiaq.de> tree-wide: Assorted spelling fixes

In particular, several occurances of funny versions of 'success',
'unknown', 'therefore', 'acknowledge', 'argument', 'achieve', 'address',
'beginning', 'desirable', 'separate' and 'necessary' are fixed.

Signed-off-by: Daniel Mack <daniel@caiaq.de>
Cc: Joe Perches <joe@perches.com>
Cc: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
/drivers/scsi/libfc/fc_fcp.c
9ddc5b6f18fbac07d2746566b73b89e89fdd4e6a 20-Jan-2010 Uwe Kleine-König <u.kleine-koenig@pengutronix.de> tree-wide: fix typos "ammount" -> "amount"

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
/drivers/scsi/libfc/fc_fcp.c
c1ecb90a66c5afc7cc5c9349f9c3714eef4a5cfb 10-Dec-2009 Chris Leech <christopher.leech@intel.com> [SCSI] libfc: reduce hold time on SCSI host lock

Introduce a new lock to protect the list of fc_fcp_pkt structs in libfc
instead of using the host lock. This reduces the contention of this heavily
used lock, and I see up to a 25% performance gain in CPU bound small I/O
tests when scaling out across multiple quad-core CPUs.

The big win is in removing the host lock from the completion path
completely, as it does not need to be held around the call to scsi_done.

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@suse.de>
/drivers/scsi/libfc/fc_fcp.c
18fa11efc279c20af5eefff2bbe814ca067e51ae 03-Nov-2009 Chris Leech <christopher.leech@intel.com> [SCSI] libfc, fcoe: fixes for highmem skb linearize panics

There are cases outside of our control that may result in a transmit
skb being linearized in dev_queue_xmit. There are a couple of bugs
in libfc/fcoe that can result in a panic at that point. This patch
contains two fixes to prevent those panics.

1) use fast cloning instead of shared skbs with dev_queue_xmit

dev_queue_xmit doen't want shared skbuffs being passed in, and
__skb_linearize will BUG if the skb is shared. FCoE is holding an extra
reference around the call to dev_queue_xmit, so that when it returns an
error code indicating the frame has been dropped it can maintain it's
own backlog and retransmit. Switch to using fast skb cloning for this
instead.

2) don't append compound pages as > PAGE_SIZE skb fragments

fc_fcp_send_data will append pages from a scatterlist to the nr_frags[]
if the netdev supports it. But, it's using > PAGE_SIZE compound pages
as a single skb_frag. In the highmem linearize case that page will be
passed to kmap_atomic to get a mapping to copy out of, but
kmap_atomic will only allow access to the first PAGE_SIZE part.
The memcpy will keep going and cause a page fault once is crosses the
first boundary.

If fc_fcp_send_data uses linear buffers from the start, it calls
kmap_atomic one PAGE_SIZE at a time. That same logic needs to be
applied when setting up skb_frags.

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@suse.de>
/drivers/scsi/libfc/fc_fcp.c
349e11faa84ebdd6e484572cfe66f2cf4cb483a1 03-Nov-2009 Mike Christie <michaelc@cs.wisc.edu> [SCSI] libfc: do not use DID_NO_CONNECT for pkt alloc failures.

DID_NO_CONNECT is not a nice value to use for pkt alloc failures,
because you can probably retry and IO will become available again.
For the device reset callout, we do not want to set the scsi command
result for the above reason, and because we do not need to set
the scsi_cmd->result in this path. We and other drivers do not set it
for success for example, and we do not set it for other failure.
And scsi-ml does not send every command through this path, and it is
not expecting us to use the scsi_cmnd struct like a cmd coming thruogh
queuecommand. I think it is more for storage in case we need a cmd
struct for a tmf and to give us certain params like the LUN.

Patch was made over scsi-misc today.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
/drivers/scsi/libfc/fc_fcp.c
84c3e1ad08d4be018a95e7a9964bf3dbc8cf8857 03-Nov-2009 Vasu Dev <vasu.dev@intel.com> [SCSI] libfc: adds can_queue ramp up

Adds last_can_queue_ramp_down_time and updates this on every
ramp down. If last_can_queue_ramp_down_time is not zero then
do ramp up on any IO completion in added fc_fcp_can_queue_ramp_up.

Reset last_can_queue_ramp_down_time to zero once can_queue
is ramped up to added max_can_queue limit, this is to avoid any
more ramp up attempts on subsequent IO completion.

The ramp down and up are skipped for FC_CAN_QUEUE_PERIOD
to avoid infrequent changes to can_queue, this required
keeping track of ramp up time also in last_can_queue_ramp_up_time.

Adds code to ramp down can_queue if lp->qfull is set, with added
new ramp up code the can_queue will be increased after
FC_CAN_QUEUE_PERIOD, therefore it is safe to do ramp down
without fsp in this case and will avoid thrash. This required
fc_fcp_can_queue_ramp_down locking change so that it can be
called with Scsi_Host lock held.

Removes si->throttled and fsp state FC_SRB_NOMEM, not needed with
added ramp up code.

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>
/drivers/scsi/libfc/fc_fcp.c
c46be11a683acc1ccf86883ea906f171b90ff29a 03-Nov-2009 Vasu Dev <vasu.dev@intel.com> [SCSI] libfc: reduce can_queue for all FCP frame allocation failures

Currently can_queue is reduced only if frame alloc fails
during fc_fcp_send_data but frame alloc can fail at several
other places in FCP data path and can_queue needs to be
reduced for any FCP frame alloc failure.

This patch adds fc_fcp_frame_alloc for all FCP frame allocations
and if fc_frame_alloc fails in fc_fcp_frame_alloc then reduce
can_queue in fc_fcp_frame_alloc, this will reduce can_queue for
all FCP frame alloc failures.

This required moving fc_fcp_reduce_can_queue up, to build without
adding its prototype. Also renamed fc_fcp_reduce_can_queue to
fc_fcp_can_queue_ramp_down.

Removes fc_fcp_reduce_can_queue calling from fc_fcp_recv since
not needed with added fc_fcp_frame_alloc reducing can_queue.

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>
/drivers/scsi/libfc/fc_fcp.c
a7bbc7f40aa01eefef3d367349e1e6e87881a305 03-Nov-2009 Vasu Dev <vasu.dev@intel.com> [SCSI] fcoe, libfc: use single frame allocation API

Cleans up frame allocation APIs to have just single fc_frame_alloc API.

Removes _fc_frame_alloc, renames __fc_frame_alloc to _fc_frame_alloc.

Modifies fc_fcp_send_data for removed _fc_frame_alloc, fc_fcp_send_data
was the only user of removed _fc_frame_alloc.

Also Adds check in fc_frame_alloc to do mod by 4 for only non-zero
len value.

This patch is prep work to fix can_queue reducing in next patch.
Single fc_frame_alloc API helps in fixing can_queue reducing in
next patch.

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>
/drivers/scsi/libfc/fc_fcp.c
3a3b42bf89a9b90ae9ed2c57fdc378e5473a0ef9 03-Nov-2009 Robert Love <robert.w.love@intel.com> [SCSI] libfc: Formatting cleanups across libfc

This patch makes a variety of cleanup changes to all libfc files.

This patch adds kernel-doc headers to all functions lacking them
and attempts to better format existing headers. It also add kernel-doc
headers to structures.

This patch ensures that the current naming conventions for local ports,
remote ports and remote port private data is upheld in the following
manner.

struct instance (i.e. variable name)
--------------------------------------------------
fc_lport lport
fc_rport rport
fc_rport_libfc_priv rpriv
fc_rport_priv rdata

I also renamed dns_rp and ptp_rp to dns_rdata and ptp_rdata
respectively.

I used emacs 'indent-region' and 'tabify' on all libfc files
to correct spacing alignments.

I feel sorry for anyone attempting to review this patch.

Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
/drivers/scsi/libfc/fc_fcp.c
5868287460b0fc243e828a0b856cd53d8bf45739 03-Nov-2009 Robert Love <robert.w.love@intel.com> [SCSI] libfc: Add routine to copy data from a buffer to a SG list

When handling the multi-frame responses of fc pass-thru requests,
a code segment similar to fc_fcp_recv_data (routine to receive
inbound SCSI data) is used in the response handler. This patch
is to add a routine, called fc_copy_buffer_to_sglist(), to handle
the common function of copying data from a buffer to a scatter-
gather list in order to avoid code duplication.

Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
/drivers/scsi/libfc/fc_fcp.c
93e6d5ab9969a9200752658677eafd96772302f0 03-Nov-2009 Robert Love <robert.w.love@intel.com> [SCSI] libfc: Move libfc_init and libfc_exit to fc_libfc.c

These routines are for the libfc kernel module and should be in
the libfc .c file.

Moving the libfc __init routine into fc_libfc.c caused the creation
of the fc_setup_fcp() and fc_destroy_fcp() routines so that
scsi_pkt_cachep was not exposed outside of fc_fcp.c.

Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
/drivers/scsi/libfc/fc_fcp.c
8866a5d9075b7129194576f5f810e85a693c40ba 03-Nov-2009 Robert Love <robert.w.love@intel.com> [SCSI] libfc: Add libfc/fc_libfc.[ch] for libfc internal routines

include/scsi/libfc.h is currently loaded with common code
shared between libfc's sub-modules as well as shared between
libfc and fcoe. Previous patches attempted to move out
non-common code. This patch creates two files for common
libfc routines that will not be shared with fcoe, fnic or
any other LLDs.

Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
/drivers/scsi/libfc/fc_fcp.c
255f6386b816b2bc0c251af0ee4985ad5a8461b7 03-Nov-2009 Robert Love <robert.w.love@intel.com> [SCSI] libfc: Remove fc_fcp_complete

This function is never used, let's remove it.

Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
/drivers/scsi/libfc/fc_fcp.c
229b8d72f3eccf97e8a9e22436e8fc303b3483cd 16-Oct-2009 Vasu Dev <vasu.dev@intel.com> [SCSI] libfc: add queue_depth ramp up

Adjust queue_depth on fc_change_queue_depth call back
with reason SCSI_QDEPTH_RAMP_UP, no additional resource
adjustments necessary for libfc.

Signed-off-by: Vasu Dev <vasu.dev@intel.com>
Acked-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
/drivers/scsi/libfc/fc_fcp.c
14caf44c69184ed72d46a2f883311daf27a4192f 16-Oct-2009 Vasu Dev <vasu.dev@intel.com> [SCSI] fcoe, libfc: fix an libfc issue with queue ramp down in libfc

The cmd_per_lun value is used by scsi-ml as fall back lowest
queue_depth value but in case of libfc cmd_per_lun is set to
same value as max queue_depth = 32.

So this patch reduces cmd_per_lun value to 3 and configures
each lun with default max queue_depth 32 in fc_slave_alloc.

Signed-off-by: Vasu Dev <vasu.dev@intel.com>
Acked-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
/drivers/scsi/libfc/fc_fcp.c
5c20848a096fb1880ded99816be79d78ca1cd696 16-Oct-2009 Mike Christie <michaelc@cs.wisc.edu> [SCSI] libfc: convert to scsi_track_queue_full

This converts the libfc using scsi_track_queue_full to
track the queue full from the change_queue_depth callback.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Vasu Dev <vasu.dev@intel.com>
Acked-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
/drivers/scsi/libfc/fc_fcp.c
e881a172dac4d9ea3b2a1540041d872963c269bd 16-Oct-2009 Mike Christie <michaelc@cs.wisc.edu> [SCSI] modify change_queue_depth to take in reason why it is being called

This patch modifies scsi_host_template->change_queue_depth so that
it takes an argument indicating why it is being called. This will be
used so that if a LLD needs to do some extra processing when
handling queue fulls or later ramp ups, it can do so.

This is a simple port of the drivers setting a change_queue_depth
callback. In the patch I just have these LLDs adjust the queue depth
if the user was requesting it.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>

[Vasu.Dev: v2
Also converted pmcraid_change_queue_depth and then verified
all modules compile using "make allmodconfig" for any new build
warnings on X86_64.

Updated original description after combing two original
patches from Mike to make this patch git bisectable.]
Signed-off-by: Vasu Dev <vasu.dev@intel.com>
[jejb: fixed up 53c700]
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
/drivers/scsi/libfc/fc_fcp.c
8f550f937e9fdafa5c37e348e214aecec851ef3f 22-Oct-2009 Chris Leech <christopher.leech@intel.com> [SCSI] libfc: fix memory corruption caused by double frees and bad error handling

I was running into several different panics under stress, which I traced down
to a few different possible slab corruption issues in error handling paths.
I have not yet looked into why these exchange sends fail, but with these
fixes my test system is much more stable under stress than before.

fc_elsct_send() could fail and either leave the passed in frame intact
(failure in fc_ct/els_fill) or the frame could have been freed if the
failure was is fc_exch_seq_send(). The caller had no way of knowing, and
there was a potential double free in the error handling in fc_fcp_rec().

Make fc_elsct_send() always free the frame before returning, and remove the
fc_frame_free() call in fc_fcp_rec().

While fc_exch_seq_send() did always consume the frame, there were double free
bugs in the error handling of fc_fcp_cmd_send() and fc_fcp_srr() as well.

Numerous calls to error handling routines (fc_disc_error(),
fc_lport_error(), fc_rport_error_retry() ) were passing in a frame pointer that
had already been freed in the case of an error. I have changed the call
sites to pass in a NULL pointer, but there may be more appropriate error
codes to use.

Question: Why do these error routines take a frame pointer anyway? I
understand passing in a pointer encoded error to the response handlers, but
the error routines take no action on a valid pointer and should never be
called that way.

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@suse.de>
/drivers/scsi/libfc/fc_fcp.c
d37322a43ebac79eef417149f5696390cf8872db 22-Oct-2009 Yi Zou <yi.zou@intel.com> [SCSI] libfc: Fix frags in frame exceeding SKB_MAX_FRAGS in fc_fcp_send_data

In case of sequence offload, in fc_fcp_send_data(), the skb_fill_page_info()
called may end up adding more frags to the skb_shinfo(fp_skb(fp))->frags[],
exceeding SKB_MAX_FRAGS, this eventually corrupts the memory. I am adding the
FR_FRAME_SG_LEN back, but as SKB_MAX_FRAGS -1, leaving 1 for our fcoe_eof_crc
page. And send will be broken into multiple large sends if the frame already
contains more frags than skb handle.

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>
/drivers/scsi/libfc/fc_fcp.c
4347fa66878e079766258bc0d077c350cb31a799 22-Oct-2009 Yi Zou <yi.zou@intel.com> [SCSI] libfc: Fix wrong scsi return status under FC_DATA_UNDRUN

This bug is exposed when there is a link flap in LLD. Particularly, when it
happens right after a SCSI write command is sent out, no FCP_DATA is sent,
causing fsp->status_code to be set as FC_DATA_UNDRUN in fc_fcp_complete_locked
even no SCSI status is received. Consequently, fc_io_compl treats this as DID_OK.
This results in SCSI returning successful to the initial I/O request even
there is no DATA actually sent. Particularly, if you run an I/O tool w/ data
verification on, the read back for verification is gonna fail.

This is fixed here by checking when FC_DATA_UNDRUN happens, SCSI status is
received w/ FC_SRB_RCV_STATUS set in fsp->state.

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>
/drivers/scsi/libfc/fc_fcp.c
c340111dbb48482cd23f4e441deff9169be9bc6f 22-Oct-2009 Robert Love <robert.w.love@intel.com> [SCSI] libfc: Remove unused fc_lport pointer from fc_fcp_pkt_abort

This argument isn't used, let's not pass it into the routine.

Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
/drivers/scsi/libfc/fc_fcp.c
473e28563fbb038515d4616546297483d3727c02 22-Oct-2009 Robert Love <robert.w.love@intel.com> [SCSI] libfc, fcoe: Don't EXPORT_SYMBOLS unnecessarily

These are a few functions that were not used by other
modules. They did not need to be exported so this patch
removes the EXPORT_SYMBOLS call for each.

Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
/drivers/scsi/libfc/fc_fcp.c
5e472d077f45de4f37365171bd742f18b3ef20de 22-Oct-2009 Yi Zou <yi.zou@intel.com> [SCSI] libfc: fix ddp in fc_fcp for 0 xid

xid 0 was used as an indication of invalid xid before but now xid 0
can be used as a valid exchange i. This patch fixes the ddp completion
in fcp layer, i.e., in fc_fcp.c:fc_fcp_ddp_done() function, to make sure it
does not use xid 0 for indication of an invalid xid, instead, it now
uses use FC_XID_UNKNOWN for such indication.

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>
/drivers/scsi/libfc/fc_fcp.c
a46f327aa5caf2cce138e98ddd863b6cca0e71e2 25-Aug-2009 Joe Eykholt <jeykholt@cisco.com> [SCSI] libfc: change elsct to use FC_ID instead of rdata

tt.elsct_send is used by both FCP and by the rport state machine.
After further patches, these two modules will use different
structures for the remote port.

So, change elsct_send to use the FC_ID instead of the fc_rport_priv
as its argument. It currently only uses the FC_ID anyway.

For CT requests the destination FC_ID is still implicitly 0xfffffc.
After further patches the did arg on CT requests will be used to
specify the FC_ID being inquired about for GPN_ID or other queries.

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>
/drivers/scsi/libfc/fc_fcp.c
9fb9d32831fd687e427ec5b147bb690f468b99a0 25-Aug-2009 Joe Eykholt <jeykholt@cisco.com> [SCSI] libfc: make fc_rport_priv the primary rport interface.

The rport and discovery modules deal with remote ports
before fc_remote_port_add() can be done, because the
full set of rport identifiers is not known at early stages.

In preparation for splitting the fc_rport/fc_rport_priv allocation,
make fc_rport_priv the primary interface for the remote port and
discovery engines.

The FCP / SCSI layers still deal with fc_rport and
fc_rport_libfc_priv, however.

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>
/drivers/scsi/libfc/fc_fcp.c
53fcfbbef569819706b880a502ff62e2852edfce 30-Jul-2009 Yi Zou <yi.zou@intel.com> [SCSI] libfc: Remove page flags check for sglist

I don't believe this check is needed any more in the current kernel, which,
if I understand correctly, is for compound page where only the first page
is supposed to get ref-counted.

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>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
/drivers/scsi/libfc/fc_fcp.c
537029f8e950776951ca2a3fe30121d5c05643d1 30-Jul-2009 Yi Zou <yi.zou@intel.com> [SCSI] libfc: Remove FC_FRAME_SG_LEN in fc_fcp_send_data

FC_FRAME_SG_LEN is 4 which is too small when offload is enabled. Actually, the
WARN_ON() in fc_fcp_send_data() should be:

WARN_ON(skb_shinfo(fp_skb(fp))->nr_frags > MAX_SKB_FRAGS);

But since we will not get anything more than 64K anyway, so there is no need
to do this anyway here. Therefore, I am getting rid of FC_FRAME_SG_LEN here
and the WARN_ON here.

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>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
/drivers/scsi/libfc/fc_fcp.c
7414705ea4aef9ce438e547f3138a680d2d1096c 11-Jun-2009 Robert Love <robert.w.love@intel.com> libfc: Add runtime debugging with debug_logging module parameter

This patch adds the /sys/module/libfc/parameters/debug_logging
file to sysfs as a module parameter. It accepts an integer
bitmask for logging. Currently it supports:

bit
LSB 0 = general libfc debugging
1 = lport debugging
2 = disc debugging
3 = rport debugging
4 = fcp debugging
5 = EM debugging
6 = exch/seq debugging
7 = scsi logging (mostly error handling)

the other bits are not used at this time.

The patch converts all of the libfc source files to use
these new macros and removes the old FC_DBG macro.

Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
/drivers/scsi/libfc/fc_fcp.c
d5e6054a0a097527b3920a8a0aefe7f830c014fd 06-May-2009 Mike Christie <michaelc@cs.wisc.edu> [SCSI] libfc: use DID_ERROR when we have internall aborted command

If we aborted a command, because it timed out we should not use
DID_ABORT. It will fail the command right away back to the upper
layer. We want to use something that indicated that the problem
did not complete normally, but it was not a fatal problem.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
/drivers/scsi/libfc/fc_fcp.c
a29e7646f42a325a7f6cce34adbeb52e8db15566 22-Apr-2009 Robert Love <robert.w.love@intel.com> [SCSI] libfc: Fix compilation warnings with allmodconfig

When building with a .config generated from 'make allmodconfig'
some build warnings are generated. This patch corrects the warnings,
adds a FC_FID_NONE (= 0) enumeration for FC-IDs and cleans up one
variable naming to meet our variable naming conventions. For example,
fc_lport's should be named "lport," not "lp."

Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
/drivers/scsi/libfc/fc_fcp.c
9b34ecffd59d6ed66fdd6906e8a092a33e7c8564 17-Mar-2009 Vasu Dev <vasu.dev@intel.com> [SCSI] fcoe, libfc: add libfcoe module

Just sets up build environment for libfcoe module towards a
libfcoe library for libfc LLDs using FCoE as libfc transport.

Common library code to libfcoe is added in next patch.

Also, updated MODULE_LICENSE from "GPL" string to "GPL v2" for
libfc, libfcoe and fcoe modules to accurately match the licenses.

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>
/drivers/scsi/libfc/fc_fcp.c
582b45bc577f78b5bfff3db874594ce2d962b846 01-Apr-2009 Robert Love <robert.w.love@intel.com> [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>
/drivers/scsi/libfc/fc_fcp.c
b277d2aa9a4d969002c4157bf77b76b9ad9ca04a 27-Feb-2009 Yi Zou <yi.zou@intel.com> [SCSI] libfc: add support of large receive offload by ddp in fc_fcp

When LLD supports direct data placement (ddp) for large receive of an scsi
i/o coming into fc_fcp, we call into libfc_function_template's ddp_setup()
to prepare for a ddp of large receive for this read I/O. When I/O is complete,
we call the corresponding ddp_done() to get the length of data ddped as well
as to let LLD do clean up.

fc_fcp_ddp_setup()/fc_fcp_ddp_done() are added to setup and complete a ddped
read I/O described by the given fc_fcp_pkt. They would call into corresponding
ddp_setup/ddp_done implemented by the fcoe layer. Eventually, fcoe layer calls
into LLD's ddp_setup/ddp_done provided through net_device

Signed-off-by: Yi Zou <yi.zou@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
/drivers/scsi/libfc/fc_fcp.c
276d68142b7b676594ab8739355c27e9e5b3d41d 27-Feb-2009 Yi Zou <yi.zou@intel.com> [SCSI] libfc: use lso_max for sequence offload

Make sure for large send is supported by LLD in outgoing FCP data, we are only
sending the lso_max a time in one single large send, since that is what
supported by LLD.

Signed-off-by: Yi Zou <yi.zou@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
/drivers/scsi/libfc/fc_fcp.c
1c9fbafc8c629c89183d6dccec67a8415513b0d1 04-Jan-2009 Martin K. Petersen <martin.petersen@oracle.com> [SCSI] Remove SUGGEST flags

The SUGGEST_* flags in the SCSI command result have been out of fashion
for a while and we don't actually use them in the error handling.
Remove the remaining occurrences.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
/drivers/scsi/libfc/fc_fcp.c
34f42a070fc98f5dc07e9fa2338b7b8d1dc347eb 27-Feb-2009 Robert Love <robert.w.love@intel.com> [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>
/drivers/scsi/libfc/fc_fcp.c
26d9cab558f901051d0b69b2c445c8588931ce8d 27-Feb-2009 Vasu Dev <vasu.dev@intel.com> [SCSI] libfc: fixed a read IO data integrity issue when a IO data frame lost

The fc_fcp_complete_locked detected data underrun in this case and set
the FC_DATA_UNDRUN but that was ignored by fc_io_compl for all cases
including read underrun.

Added code to not to ignore FC_DATA_UNDRUN for read IO and instead
suggested scsi-ml to retry cmd to recover from lost data frame.

Not sure if it is okay to ignore FC_DATA_UNDRUN for other case, so let
code as is for other cases but removed or-ing with zero valued fsp->cdb_status
for those cases.

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>
/drivers/scsi/libfc/fc_fcp.c
bc0e17f691085315ae9303eb5b0883fe16dfe6b1 27-Feb-2009 Vasu Dev <vasu.dev@intel.com> [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>
/drivers/scsi/libfc/fc_fcp.c
42e9a92fe6a9095bd68a379aaec7ad2be0337f7a 10-Dec-2008 Robert Love <robert.w.love@intel.com> [SCSI] libfc: A modular Fibre Channel library

libFC is composed of 4 blocks supported by an exchange manager
and a framing library. The upper 4 layers are fc_lport, fc_disc,
fc_rport and fc_fcp. A LLD that uses libfc could choose to
either use libfc's block, or using the transport template
defined in libfc.h, override one or more blocks with its own
implementation.

The EM (Exchange Manager) manages exhcanges/sequences for all
commands- ELS, CT and FCP.

The framing library frames ELS and CT commands.

The fc_lport block manages the library's representation of the
host's FC enabled ports.

The fc_disc block manages discovery of targets as well as
handling changes that occur in the FC fabric (via. RSCN events).

The fc_rport block manages the library's representation of other
entities in the FC fabric. Currently the library uses this block
for targets, its peer when in point-to-point mode and the
directory server, but can be extended for other entities if
needed.

The fc_fcp block interacts with the scsi-ml and handles all
I/O.

Signed-off-by: Robert Love <robert.w.love@intel.com>
[jejb: added include of delay.h to fix ppc64 compile prob spotted by sfr]
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
/drivers/scsi/libfc/fc_fcp.c