__scsi_remove_device (e.g. due to dev_loss_tmo) calls
zfcp_scsi_slave_destroy which in turn sends a close LUN FSF request to
the adapter. After 30 seconds without response,
zfcp_erp_timeout_handler kicks the ERP thread failing the close LUN
ERP action. zfcp_erp_wait in zfcp_erp_lun_shutdown_wait and thus
zfcp_scsi_slave_destroy returns and then scsi_device is no longer
valid. Sometime later the response to the close LUN FSF request may
finally come in. However, commit
b62a8d9b45
"[SCSI] zfcp: Use SCSI device data zfcp_scsi_dev instead of zfcp_unit"
introduced a number of attempts to unconditionally access struct
zfcp_scsi_dev through struct scsi_device causing a use-after-free.
This leads to an Oops due to kernel page fault in one of:
zfcp_fsf_abort_fcp_command_handler, zfcp_fsf_open_lun_handler,
zfcp_fsf_close_lun_handler, zfcp_fsf_req_trace,
zfcp_fsf_fcp_handler_common.
Move dereferencing of zfcp private data zfcp_scsi_dev allocated in
scsi_device via scsi_transport_reserve_device after the check for
potentially aborted FSF request and thus no longer valid scsi_device.
Only then assign sdev_to_zfcp(sdev) to the local auto variable struct
zfcp_scsi_dev *zfcp_sdev.
Signed-off-by: Martin Peschke <mpeschke@linux.vnet.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org> #2.6.37+
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
In FC fabrics with large zones, the automatic port_rescan on incoming ELS
and any adapter recovery can cause quite some traffic at the very same
time, especially if lots of Linux images share an HBA, which is common on
s390. This can cause trouble and failures. Fix this by making such port
rescans dependent on a user configurable module parameter.
The following unconditional automatic port rescans remain as is:
On setting an adapter online and
on manual user-triggered writes to the sysfs attribute port_rescan.
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Upstream commit f3450c7b91
"[SCSI] zfcp: Replace local reference counting with common kref"
accidentally dropped a reference count check before tearing down
zfcp_ports that are potentially in use by zfcp_units.
Even remote ports in use can be removed causing
unreachable garbage objects zfcp_ports with zfcp_units.
Thus units won't come back even after a manual port_rescan.
The kref of zfcp_port->dev.kobj is already used by the driver core.
We cannot re-use it to track the number of zfcp_units.
Re-introduce our own counter for units per port
and check on port_remove.
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: <stable@vger.kernel.org> #2.6.33+
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
If list_for_each_entry, etc complete a traversal of the list, the iterator
variable ends up pointing to an address at an offset from the list head,
and not a meaningful structure. Thus this value should not be used after
the end of the iterator. Replace port->adapter->scsi_host by
adapter->scsi_host.
This problem was found using Coccinelle (http://coccinelle.lip6.fr/).
Oversight in upsteam commit of v2.6.37
a1ca48319a
"[SCSI] zfcp: Move ACL/CFDC code to zfcp_cfdc.c"
which merged the content of zfcp_erp_port_access_changed().
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Reviewed-by: Martin Peschke <mpeschke@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org> #2.6.37+
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
If the mapping of FCP device bus ID and corresponding subchannel
is modified while the Linux image is suspended, the resume of FCP
devices can fail. During resume, zfcp gets callbacks from cio regarding
the modified subchannels but they can be arbitrarily mixed with the
restore/resume callback. Since the cio callbacks would trigger
adapter recovery, zfcp could wakeup before the resume callback.
Therefore, ignore the cio callbacks regarding subchannels while
being suspended. We can safely do so, since zfcp does not deal itself
with subchannels. For problem determination purposes, we still trace the
ignored callback events.
The following kernel messages could be seen on resume:
kernel: <WWPN>: parent <FCP device bus ID> should not be sleeping
As part of adapter reopen recovery, zfcp performs auto port scanning
which can erroneously try to register new remote ports with
scsi_transport_fc and the device core code complains about the parent
(adapter) still sleeping.
kernel: zfcp.3dff9c: <FCP device bus ID>:\
Setting up the QDIO connection to the FCP adapter failed
<last kernel message repeated 3 more times>
kernel: zfcp.574d43: <FCP device bus ID>:\
ERP cannot recover an error on the FCP device
In such cases, the adapter gave up recovery and remained blocked along
with its child objects: remote ports and LUNs/scsi devices. Even the
adapter shutdown as part of giving up recovery failed because the ccw
device state remained disconnected. Later, the corresponding remote
ports ran into dev_loss_tmo. As a result, the LUNs were erroneously
not available again after resume.
Even a manually triggered adapter recovery (e.g. sysfs attribute
failed, or device offline/online via sysfs) could not recover the
adapter due to the remaining disconnected state of the corresponding
ccw device.
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org> #2.6.32+
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
The pl vector has scount elements, i.e. pl[scount-1] is the last valid
element. For maximum sized requests, payload->counter == scount after
the last loop iteration. Therefore, do bounds checking first (with
boolean shortcut) to not access the invalid element pl[scount].
Do not trust the maximum sbale->scount value from the HBA
but ensure we won't access the pl vector out of our allocated bounds.
While at it, clean up scoping and prevent unnecessary memset.
Minor fix for 86a9668a8d
"[SCSI] zfcp: support for hardware data router"
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Reviewed-by: Martin Peschke <mpeschke@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org> #3.2+
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Duplicate fssrh_2 from a54ca0f62f
"[SCSI] zfcp: Redesign of the debug tracing for HBA records."
complicates distinction of generic status read response from
local link up.
Duplicate fsscth1 from 2c55b750a8
"[SCSI] zfcp: Redesign of the debug tracing for SAN records."
complicates distinction of good common transport response from
invalid port handle.
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Reviewed-by: Martin Peschke <mpeschke@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org> #2.6.38+
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Commit a9277e7783
"[SCSI] scsi_transport_fc: Getting FC Port Speed in sync with FC-GS"
changed the semantics of FC_PORTSPEED defines to
FDMI port attributes of FC-HBA/SM-HBA
which is different from the previous bit reversed
Report Port Speed Capabilities (RPSC) ELS of FC-GS/FC-LS.
Zfcp showed "10 Gbit" instead of "4 Gbit" for supported_speeds.
It now uses explicit bit conversion as the other LLDs already
do, in order to be independent of the kernel bit semantics.
See also http://marc.info/?l=linux-scsi&m=134452926830730&w=2
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Reviewed-by: Martin Peschke <mpeschke@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org> #3.4+
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Remove the file name from the comment at top of many files. In most
cases the file name was wrong anyway, so it's rather pointless.
Also unify the IBM copyright statement. We did have a lot of sightly
different statements and wanted to change them one after another
whenever a file gets touched. However that never happened. Instead
people start to take the old/"wrong" statements to use as a template
for new files.
So unify all of them in one go.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
The new is_compat_task() define for the !COMPAT case in
include/linux/compat.h conflicts with a similar define in
arch/s390/include/asm/compat.h.
This is the minimal patch which fixes the build issues.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
zfcp_scsi_slave_destroy erroneously always tried to finish its task
even if the corresponding previous zfcp_scsi_slave_alloc returned
early. This can lead to kernel page faults on accessing uninitialized
fields of struct zfcp_scsi_dev in zfcp_erp_lun_shutdown_wait. Take the
port field of the struct to determine if slave_alloc returned early.
This zfcp bug is exposed by 4e6c82b (in turn fixing f7c9c6b to be
compatible with 21208ae) which can call slave_destroy for a
corresponding previous slave_alloc that did not finish.
This patch is based on James Bottomley's fix suggestion in
http://www.spinics.net/lists/linux-scsi/msg55449.html.
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Cc: <stable@kernel.org> #2.6.38+
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Fix several compile errors on s390 caused by splitting module.h.
Some include additions [e.g. qdio_setup.c, zfcp_qdio.c] are in
anticipation of pending changes queued for s390 that increase
the modular use footprint.
[PG: added additional obvious changes since Heiko's original patch]
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
FICON Express8S supports hardware data router, which requires an
adapted qdio request format.
This part 2/2 exploits the functionality in zfcp.
Signed-off-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
DIF/DIX support for zfcp is no longer experimental,
and config option is no longer necessary.
Return error from queuecommand for unsupported data directions.
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
This allows us to move duplicated code in <asm/atomic.h>
(atomic_inc_not_zero() for now) to <linux/atomic.h>
Signed-off-by: Arun Sharma <asharma@fb.com>
Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The qdio SBAL entry flag is made-up of four different values that are
independent of one another. Some of the bits are reserved by the
hardware and should not be changed by qdio. Currently all four values
are overwritten since the SBAL entry flag is defined as an u32.
Split the SBAL entry flag into four u8's as defined by the hardware
and don't touch the reserved bits.
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Remove the owner and name members of struct
ccw_driver and convert all drivers to store
this data in the embedded struct device_driver.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Query the FC symbolic port name for reporting in the fc_host sysfs and
enable the symbolic_name attribute in the fc_host sysfs. When running
in NPIV mode, extend the symbolic port name with the devno and the
hostname. This allows better identification of Linux systems for SAN
and storage administrators.
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
The SCSI host and transport templates are the only members left in the
global zfcp_data struct. Move them out of zfcp_data and remove the
now unused zfcp_data struct. Also update the names of the register and
unregister functions to use the zfcp_scsi prefix.
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
For task management commands, only LUN and flags are required. The
regular FCP setup already sets the LUN in the fcp_cmnd. All is
required for merging the function is setting up the TM flags.
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Move the kmem_cache for allocating the qtcb to zfcp_fsf.c and rename
it accordingly.
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Switch the allocation of the GPN_FT request data to the FC kmem_cache
and remove the zfcp_gpn kmem_cache.
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Allocate the data for the GID_PN request through the new FC
kmem_cache. While updating the GID_PN code, also introduce a helper
function for initializing the CT header for FC nameserver requests.
Remove the "paranoia" check as well, the GID_PN request data does not
suddenly change.
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
A data buffer that is passed to the hardware must not cross a page
boundary. zfcp uses a series of kmem_caches to align the data to not
cross a page boundary. Introduce a new kmem_cache for the FC requests
sent from the zfcp driver and use it for the ELS ADISC data. The goal
is to migrate to the FC kmem_cache in later patches and remove the
request specific kmem_caches.
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
zfcp requires a mempool for the status read data blocks to resubmit
the "status read" requests at any time. Each status read data block
has the size of a page (4096 bytes) and needs to be placed in one
page.
Instead of having a kmem_cache for allocating page sized chunks, use
mempool_create_page_pool to create a mempool returning pages and
remove the zfcp kmem_cache.
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Introduce a scan treshold for the qdio outbound queues. By setting the
threshold the driver can tell qdio after how much used SBALs qdio
should schedule the outbound tasklet that scans the queue for finished
SBALs. The threshold is specific by the drivers because a
Hipersockets device is much faster in utilizing outbound buffers than a
ZFCP or OSA device.
The default values after how many used SBALs the tasklet should run are:
OSA: > 31 SBALs
Hipersockets: > 7 SBALs
zfcp: > 55 SBALs
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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.
The zfcpdump tool requires a method to attach exactly one LUN. The
easiest way to achieve this is to add a new zfcp module parameter.
When allow_lun_scan is set to "false", zfcp only accepts LUNs that
have been configured through the unit_add sysfs interface.
Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
The function zfcp_cache_hw_align is only called from zfcp_module_init,
so it should be declared with __init as well.
Reviewed-by: Steffen Maier <maier@linux.vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Initialization of the qdio waitqueue should happen when the qdio data
is initialized and the QDIOUP flag should be handled in the qdio code
as well. Adjust the code accordingly and remove the superfluos
function zfcp_erp_adapter_strategy_open_qdio.
Reviewed-by: Steffen Maier <maier@linux.vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
This patch is the final cleanup of the redesign from the zfcp tracing.
Structures and elements which were used by multiple areas of the
former debug tracing are now changed to the new scheme.
Signed-off-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
This patch is the continuation to redesign the zfcp tracing to a more
straight-forward and easy to extend scheme.
This patch deals with all trace records of the zfcp SCSI area.
Signed-off-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
This patch is the continuation to redesign the zfcp tracing to a more
straight-forward and easy to extend scheme.
This patch deals with all trace records of the zfcp HBA area.
Signed-off-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
This patch is the continuation to redesign the zfcp tracing to a more
straight-forward and easy to extend scheme.
This patch deals with all trace records of the zfcp SAN area.
Signed-off-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
The tracing environment of the zfcp LLD has become very bulky and hard
to maintain. Small changes involve a large modification process which
is error-prone and not effective. This patch is the first of a set to
redesign the zfcp tracing to a more straight-forward and easy to
extend scheme. It removes all interpretation and visualization parts
and focuses on bare logging of the information.
This patch deals with all trace records of the zfcp error recovery.
Signed-off-by: Swen schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Interrupting the connection to the FCP channel while I/O requests are
being issued can lead to this deadlock. scsi_dispatch_cmd already
holds the host_lock while the recovery trigger tries to acquire the
host_lock again when iterating through the scsi_devices.
INFO: lockdep is turned off.
BUG: spinlock lockup on CPU#1, blast/9660, 0000000078f38878
CPU: 1 Not tainted 2.6.35.7SWEN2 #2
Process blast (pid: 9660, task: 0000000071f75940, ksp: 0000000074393ac0)
0000000074393640 00000000743935c0 0000000000000002 0000000000000000
0000000074393660 00000000743935d8 00000000743935d8 00000000005590c2
0000000000000000 0000000078f38878 0000000026ede800 0000000078f38878
000000000000000d 040000000000000c 0000000074393628 0000000000000000
0000000000000000 0000000000100b2a 00000000743935c0 0000000074393600
Call Trace:
([<0000000000100a32>] show_trace+0xee/0x144)
[<00000000003be202>] do_raw_spin_lock+0x112/0x178
[<000000000055d408>] _raw_spin_lock_irqsave+0x90/0xb0
[<00000000003f1514>] __scsi_iterate_devices+0x38/0xbc
[<00000000004849b0>] zfcp_erp_clear_adapter_status+0xd0/0x16c
[<000000000048587a>] zfcp_erp_adapter_reopen+0x3a/0xb4
[<0000000000489812>] zfcp_fsf_req_send+0x166/0x180
[<000000000048c8d6>] zfcp_fsf_fcp_cmnd+0x272/0x408
[<000000000048f864>] zfcp_scsi_queuecommand+0x11c/0x1e0
[<00000000003f1f2a>] scsi_dispatch_cmd+0x1d6/0x324
[<00000000003f9910>] scsi_request_fn+0x42c/0x56c
[<00000000003828ae>] __blk_run_queue+0x86/0x140
[<000000000037f742>] elv_insert+0x11a/0x208
[<000000000038104c>] blk_insert_cloned_request+0x84/0xe4
[<000003c0032b7c64>] dm_dispatch_request+0x6c/0x94 [dm_mod]
[<000003c0032b7d5c>] map_request+0xd0/0x100 [dm_mod]
[<000003c0032b9a78>] dm_request_fn+0xec/0x1bc [dm_mod]
[<0000000000382c0e>] generic_unplug_device+0x5a/0x6c
[<000003c0032b7f98>] dm_unplug_all+0x74/0x9c [dm_mod]
[<00000000001d1272>] sync_page+0x76/0x9c
[<00000000001d12ba>] sync_page_killable+0x22/0x60
[<000000000055a768>] __wait_on_bit_lock+0xc0/0x124
[<00000000001d1140>] __lock_page_killable+0x78/0x84
[<00000000001d351c>] generic_file_aio_read+0x5a4/0x7e8
[<0000000000228ec0>] do_sync_read+0xc8/0x12c
[<0000000000229edc>] vfs_read+0xac/0x1ac
[<000000000022a0d8>] SyS_read+0x58/0xa8
[<00000000001146de>] sysc_noemu+0x10/0x16
[<00000200000493c4>] 0x200000493c4
INFO: lockdep is turned off.
Call zfcp_fsf_fcp_cmnd without the host_lock and disable the
interrupts when acquiring the req_q_lock. According to the patch
description in "[PATCH] Eliminate error handler overload of the SCSI
serial number", the serial_number is not used, so simply drop the
queuecommand wrapper function and run zfcp_scsi_queuecommand without
holding the host_lock.
Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
The ERP got values assigned for which no reference was taken. This
can lead to an unpredictable race condition. Fix this by only
assigning the values which are required and for which a reference was
pulled or is held implicitly.
Signed-off-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
If the evaluation of GPN_FT requests wants to remove an invalid port
from the system the zfcp_erp_port_shutdown function is triggered.
Depending on the system status a superior action (e.g. adapter reopen)
is required. This can lead to an invalid mem access of the port struct
which might be freed at the time since the superior action is not
holding a reference of the port which triggered this ERP action.
Signed-off-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
The request data assignment between the fsf abort initiator and its
corresponding handler is not consistent and leads to an unpredictable
behaviour, e.g. kernel panic. This patch fixes this issue and assigns
the correct value.
Signed-off-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James 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: Jeff Garzik <jgarzik@redhat.com>
Acked-by: James Bottomley <James.Bottomley@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use the FCP_RSP_INFO length to correctly skip the FCP_RSP_INFO field.
Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
zfcp_unit_release calls put_device on the port. Ensure that get_device
has been called before possibly triggering the release function
through put_device or device_unregister.
Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
If an exchange config is executed while the local link is down, the
request succeeds but the returned data is incomplete. Proceeding with
the adapter activation is leading to an unpredictable behaviour (e.g.
kernel panic) caused by invalid values. In such a scenario the
recommended ERP is to retry the action and wait for a link up event.
If the issue persists the activation has to fail.
Signed-off-by: Swen Schillig <swen@vnet.ibm.com>
Sigend-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>