Commit Graph

216 Commits

Author SHA1 Message Date
Linus Torvalds
ca520cab25 Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking and atomic updates from Ingo Molnar:
 "Main changes in this cycle are:

   - Extend atomic primitives with coherent logic op primitives
     (atomic_{or,and,xor}()) and deprecate the old partial APIs
     (atomic_{set,clear}_mask())

     The old ops were incoherent with incompatible signatures across
     architectures and with incomplete support.  Now every architecture
     supports the primitives consistently (by Peter Zijlstra)

   - Generic support for 'relaxed atomics':

       - _acquire/release/relaxed() flavours of xchg(), cmpxchg() and {add,sub}_return()
       - atomic_read_acquire()
       - atomic_set_release()

     This came out of porting qwrlock code to arm64 (by Will Deacon)

   - Clean up the fragile static_key APIs that were causing repeat bugs,
     by introducing a new one:

       DEFINE_STATIC_KEY_TRUE(name);
       DEFINE_STATIC_KEY_FALSE(name);

     which define a key of different types with an initial true/false
     value.

     Then allow:

       static_branch_likely()
       static_branch_unlikely()

     to take a key of either type and emit the right instruction for the
     case.  To be able to know the 'type' of the static key we encode it
     in the jump entry (by Peter Zijlstra)

   - Static key self-tests (by Jason Baron)

   - qrwlock optimizations (by Waiman Long)

   - small futex enhancements (by Davidlohr Bueso)

   - ... and misc other changes"

* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (63 commits)
  jump_label/x86: Work around asm build bug on older/backported GCCs
  locking, ARM, atomics: Define our SMP atomics in terms of _relaxed() operations
  locking, include/llist: Use linux/atomic.h instead of asm/cmpxchg.h
  locking/qrwlock: Make use of _{acquire|release|relaxed}() atomics
  locking/qrwlock: Implement queue_write_unlock() using smp_store_release()
  locking/lockref: Remove homebrew cmpxchg64_relaxed() macro definition
  locking, asm-generic: Add _{relaxed|acquire|release}() variants for 'atomic_long_t'
  locking, asm-generic: Rework atomic-long.h to avoid bulk code duplication
  locking/atomics: Add _{acquire|release|relaxed}() variants of some atomic operations
  locking, compiler.h: Cast away attributes in the WRITE_ONCE() magic
  locking/static_keys: Make verify_keys() static
  jump label, locking/static_keys: Update docs
  locking/static_keys: Provide a selftest
  jump_label: Provide a self-test
  s390/uaccess, locking/static_keys: employ static_branch_likely()
  x86, tsc, locking/static_keys: Employ static_branch_likely()
  locking/static_keys: Add selftest
  locking/static_keys: Add a new static_key interface
  locking/static_keys: Rework update logic
  locking/static_keys: Add static_key_{en,dis}able() helpers
  ...
2015-09-03 15:46:07 -07:00
Peter Senna Tschudin
3b97487445 s390: remove unneeded semicolon
Remove unneeded semicolon.

The semantic patch that detects this change is available
at scripts/coccinelle/misc/semicolon.cocci.

Signed-off-by: Peter Senna Tschudin <peter.senna@gmail.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-08-07 09:57:00 +02:00
Peter Zijlstra
805de8f43c atomic: Replace atomic_{set,clear}_mask() usage
Replace the deprecated atomic_{set,clear}_mask() usage with the now
ubiquous atomic_{or,andnot}() functions.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-27 14:06:24 +02:00
Martin Peschke
1b33ef2394 zfcp: remove access control tables interface (port leftovers)
This patch removes some leftovers for commit
663e0890e3
"[SCSI] zfcp: remove access control tables interface".

The "access denied" case for ports is gone, as well.
The corresponding flag was cleared, but never set.
So clean it up.

Sysfs flag is kept, though, for backward-compatibility.
Now it returns always 0.

Signed-off-by: Martin Peschke <mpeschke@linux.vnet.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-11-20 09:11:28 +01:00
Martin Peschke
ff5e5842c3 [SCSI] zfcp: dead code removal
Get rid of unused function zfcp_fsf_get_req and corresponding
prototype definition.

Commit a54ca0f62f in v2.6.28
"[SCSI] zfcp: Redesign of the debug tracing for HBA records."
accidentally introduced this code which was dead in the first place.

Signed-off-by: Martin Peschke <mpeschke@linux.vnet.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-09-03 07:27:56 -07:00
Martin Peschke
75a1408d32 [SCSI] zfcp: consistently use appropriate SBAL flag definitions
minor cleanup for status read request

Signed-off-by: Martin Peschke <mpeschke@linux.vnet.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-09-03 07:27:55 -07:00
Steffen Maier
9edf7d75ee [SCSI] zfcp: status read buffers on first adapter open with link down
Commit 64deb6efdc
"[SCSI] zfcp: Use status_read_buf_num provided by FCP channel"
started using a value returned by the channel but only evaluated the value
if the fabric link is up.
Commit 8d88cf3f3b
"[SCSI] zfcp: Update status read mempool"
introduced mempool resizings based on the above value.
On setting an FCP device online for the very first time since boot, a new
zeroed adapter object is allocated. If the link is down, the number of
status read requests remains zero. Since just the config data exchange is
incomplete, we proceed with adapter open recovery. However, we
unconditionally call mempool_resize with adapter->stat_read_buf_num == 0 in
this case.

This causes a kernel message "kernel BUG at mm/mempool.c:131!" in process
"zfcperp<FCP-device-bus-ID>" with last function mempool_resize in Krnl PSW
and zfcp_erp_thread in the Call Trace.

Don't evaluate channel values which are invalid on link down. The number of
status read requests is always valid, evaluated, and set to a positive
minimum greater than zero. The adapter open recovery can proceed and the
channel has status read buffers to inform us on a future link up event.
While we are not aware of any other code path that could result in mempool
resize attempts of size zero, we still also initialize the number of status
read buffers to be posted to a static minimum number on adapter object
allocation.

Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org> #2.6.35+
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-05-31 16:32:38 -07:00
Martin Peschke
663e0890e3 [SCSI] zfcp: remove access control tables interface
This patch removes an interface that was used to manage access control
tables within the HBA. The patch consequently removes the handling
for conditions related to those access control tables, too.

That initiator-based access control feature was only needed until the
introduction of NPIV and was withdrawn with z10 years ago.
It's time to cleanup the corresponding device driver code.

Signed-off-by: Martin Peschke <mpeschke@linux.vnet.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-05-31 16:32:38 -07:00
Daniel Hansel
f76ccaac4f [SCSI] zfcp: fix adapter (re)open recovery while link to SAN is down
FCP device remains in status ERP_FAILED when device is switched online
or adapter recovery is triggered  while link to SAN is down.

When Exchange Configuration Data command returns the FSF status
FSF_EXCHANGE_CONFIG_DATA_INCOMPLETE it aborts the exchange process.
The only retries are done during the common error recovery procedure
(i.e. max. 3 retries with 8sec sleep between) and remains in status
ERP_FAILED with QDIO down.

This commit reverts the commit 0df138476c
(zfcp: Fix adapter activation on link down).
When FSF status FSF_EXCHANGE_CONFIG_DATA_INCOMPLETE is received the
adapter recovery will be finished without any retries. QDIO will be
up now and status changes such as LINK UP will be received now.

Signed-off-by: Daniel Hansel <daniel.hansel@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>
2013-05-31 16:32:37 -07:00
Heiko Carstens
1aae0560d1 s390/time: rename tod clock access functions
Fix name clash with some common code device drivers and add "tod"
to all tod clock access function names.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-02-14 15:55:10 +01:00
Martin Peschke
d436de8ce2 [SCSI] zfcp: only access zfcp_scsi_dev for valid scsi_device
__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>
2012-09-24 12:11:02 +04:00
Steffen Maier
43f60cbd56 [SCSI] zfcp: No automatic port_rescan on events
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>
2012-09-24 12:11:02 +04:00
Steffen Maier
0100998dbf [SCSI] zfcp: Make trace record tags unique
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>
2012-09-24 12:11:01 +04:00
Steffen Maier
d22019778c [SCSI] zfcp: Adapt to new FC_PORTSPEED semantics
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>
2012-09-24 12:11:01 +04:00
Heiko Carstens
a53c8fab3f s390/comments: unify copyright messages and remove file names
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>
2012-07-20 11:15:04 +02:00
Swen Schillig
86a9668a8d [SCSI] zfcp: support for hardware data router
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>
2011-08-27 08:37:03 -06:00
Steffen Maier
cc405acee2 [SCSI] zfcp: non-experimental support for DIF/DIX
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>
2011-08-27 08:37:00 -06:00
Jan Glauber
3ec90878ba [S390] qdio: Split SBAL entry flags
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>
2011-06-06 14:14:56 +02:00
Lucas De Marchi
25985edced Fix common misspellings
Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-31 11:26:23 -03:00
Christof Schmitt
2443c8b23a [SCSI] zfcp: Merge FCP task management setup with regular FCP command setup
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>
2011-02-25 12:02:14 -05:00
Christof Schmitt
259afe2ed9 [SCSI] zfcp: Move qtcb kmem_cache to zfcp_fsf.c
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>
2011-02-25 12:02:12 -05:00
Christof Schmitt
c7b279ae51 [SCSI] zfcp: Replace kmem_cache for "status read" data
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>
2011-02-25 12:01:59 -05:00
Christof Schmitt
7c35e77b96 [SCSI] zfcp: Remove unused flag ZFCP_STATUS_FSFREQ_TASK_MANAGEMENT
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>
2011-02-25 12:01:09 -05:00
Tobias Klauser
4e7d7af4df [SCSI] zfcp: Remove redundant unlikely()
IS_ERR() already implies unlikely(), so it can be omitted here.

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
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>
2011-02-25 12:00:36 -05:00
Swen Schillig
ea4a3a6ac4 [SCSI] zfcp: Redesign of the debug tracing final cleanup.
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>
2010-12-21 12:24:46 -06:00
Swen Schillig
250a1352b9 [SCSI] zfcp: Redesign of the debug tracing for SCSI records.
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>
2010-12-21 12:24:46 -06:00
Swen Schillig
a54ca0f62f [SCSI] zfcp: Redesign of the debug tracing for HBA records.
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>
2010-12-21 12:24:45 -06:00
Swen Schillig
2c55b750a8 [SCSI] zfcp: Redesign of the debug tracing for SAN records.
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>
2010-12-21 12:24:45 -06:00
Christof Schmitt
e55f87531c [SCSI] zfcp: Issue FCP command without holding SCSI host_lock
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>
2010-12-09 09:41:23 -06:00
Swen Schillig
6fbf25e86b [SCSI] zfcp: Correct false abort data assignment.
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>
2010-12-09 09:41:18 -06:00
Swen Schillig
5bfb2c3148 [SCSI] zfcp: Fix common FCP request reception
The reception of a common FCP request should only be evaluated if the
corresponding SCSI request data is available. Therefore put the
information under the lock protection and verify the existence before
processing.  This fixes the following kernel panic.

Unable to handle kernel pointer dereference at virtual kernel address 0000000180000000
Oops: 003b [#1] PREEMPT SMP DEBUG_PAGEALLOC
CPU: 0 Not tainted 2.6.35.7-45.x.20101007-s390xdefault #1
Process blast (pid: 9711, task: 00000000a3be8e40, ksp: 00000000b221bac0)
Krnl PSW : 0704300180000000 0000000000489878 (zfcp_fsf_fcp_handler_common+0x4c/0x3a0)
           R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:0 CC:3 PM:0 EA:3
Krnl GPRS: 00000000b663c1b8 0000000180000000 000000007ab5bdf0 0000000000000000
           00000000b0ccd800 0000000000000018 07000000a3be8e78 00000000b5d3e600
           000000007ab5bdf0 0000000000000066 00000000b72137f0 00000000b72137f0
           0000000000000000 00000000005a8178 00000000bdf37a60 00000000bdf379f0
Krnl Code: 0000000000489866: e3c030000004       lg      %r12,0(%r3)
           000000000048986c: e310c0000004       lg      %r1,0(%r12)
           0000000000489872: e31011e00004       lg      %r1,480(%r1)
          >0000000000489878: 581011ec           l       %r1,492(%r1)
           000000000048987c: a774001c           brc     7,4898b4
           0000000000489880: b91400b1           lgfr    %r11,%r1
           0000000000489884: 5810405c           l       %r1,92(%r4)
           0000000000489888: 5510d00c           cl      %r1,12(%r13)
Call Trace:
([<000000000010d344>] debug_event_common+0x22c/0x244)
 [<000000000048a0b4>] zfcp_fsf_fcp_cmnd_handler+0x2c/0x3b4
 [<000000000048b5b6>] zfcp_fsf_req_complete+0x1b6/0x9dc
 [<000000000048bede>] zfcp_fsf_reqid_check+0x102/0x138
 [<000000000048e478>] zfcp_qdio_int_resp+0x70/0x110
 [<000000000044a1ec>] qdio_kick_handler+0xb0/0x19c
 [<000000000044c228>] __tiqdio_inbound_processing+0x30c/0xebc
 [<000000000014a5fc>] tasklet_action+0x1b4/0x1e8
 [<000000000014b676>] __do_softirq+0x106/0x1cc
 [<000000000010d91a>] do_softirq+0xe6/0xec
 [<000000000014b0c8>] irq_exit+0xd4/0xd8
 [<00000000004307ec>] do_IRQ+0x7c0/0xf54
 [<0000000000114d28>] io_return+0x0/0x16
 [<000000000055fef0>] sub_preempt_count+0x50/0xe4
([<00000000b1f873c0>] 0xb1f873c0)
 [<000000000055e25a>] _raw_spin_unlock+0x46/0x74
 [<0000000000241c40>] __d_lookup+0x288/0x2c8
 [<000000000023502c>] do_lookup+0x7c/0x25c
 [<0000000000237fa8>] link_path_walk+0x5e4/0xe2c
 [<0000000000238a00>] path_walk+0x98/0x148
 [<0000000000238c98>] do_path_lookup+0x74/0xc0
 [<000000000023989c>] user_path_at+0x64/0xa4
 [<000000000022e366>] vfs_fstatat+0x4e/0xb0
 [<000000000022e4d6>] SyS_newstat+0x2e/0x54
 [<00000000001146de>] sysc_noemu+0x10/0x16
 [<0000020000153456>] 0x20000153456
INFO: lockdep is turned off.
Last Breaking-Event-Address:
 [<000000000048a0ae>] zfcp_fsf_fcp_cmnd_handler+0x26/0x3b4

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>
2010-12-09 09:41:17 -06:00
Swen Schillig
0df138476c [SCSI] zfcp: Fix adapter activation on link down
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>
2010-10-25 09:42:35 -05:00
Swen Schillig
edaed859e6 [SCSI] zfcp: Replace status modifier functions.
Replace the zfcp_modify_<xxx>_status functions and its accompanying wrappers
with dedicated status modifier functions. This eases code readability and
maintenance.

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>
2010-09-16 22:54:23 -04:00
Christof Schmitt
a1ca48319a [SCSI] zfcp: Move ACL/CFDC code to zfcp_cfdc.c
Move the code evaluating the ACL/CFDC specific errors to the file
zfcp_cfdc.c. With this change, all code related to the old access
control feature is kept in one file, not split across zfcp_erp.c and
zfcp_fsf.c.

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>
2010-09-16 22:54:21 -04:00
Christof Schmitt
c61b536c97 [SCSI] zfcp: Reorder FCP I/O and task management handler functions
Instead of calling the same handler for both, I/O and task management
commands, use different handlers that call a function for the common
part.

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>
2010-09-16 22:54:20 -04:00
Christof Schmitt
44a24cb373 [SCSI] zfcp: Change spin_lock_bh to spin_lock_irq to fix lockdep warning
With the change to use the data on the SCSI device, iterating through
all LUNs/scsi_devices takes the SCSI host_lock. This triggers warnings
from the lock dependency checker:

=========================================================
[ INFO: possible irq lock inversion dependency detected ]
2.6.34.1 #97
---------------------------------------------------------
chchp/3224 just changed the state of lock:
 (&(shost->host_lock)->rlock){-.-...}, at: [<00000000003a73f4>] __scsi_iterate_devices+0x38/0xbc
but this lock took another, HARDIRQ-unsafe lock in the past:
 (&(&qdio->req_q_lock)->rlock){+.-...}

and interrupts could create inverse lock ordering between them.

other info that might help us debug this: [   24.972394] 2 locks held by chchp/3224:
 #0:  (&(sch->lock)->rlock){-.-...}, at: [<0000000000401efa>] do_IRQ+0xb2/0x1e4
 #1:  (&adapter->port_list_lock){.-....}, at: [<0000000000490302>] zfcp_erp_modify_adapter_status+0x9e/0x16c
[...]

=========================================================
[ INFO: possible irq lock inversion dependency detected ]
2.6.34.1 #98
---------------------------------------------------------
chchp/3235 just changed the state of lock:
 (&(shost->host_lock)->rlock){-.-...}, at: [<00000000003a73f4>] __scsi_iterate_devices+0x38/0xbc
but this lock took another, HARDIRQ-unsafe lock in the past:
 (&(&qdio->stat_lock)->rlock){+.-...}

and interrupts could create inverse lock ordering between them.

other info that might help us debug this:
2 locks held by chchp/3235:
 #0:  (&(sch->lock)->rlock){-.-...}, at: [<0000000000401efa>] do_IRQ+0xb2/0x1e4
 #1:  (&adapter->port_list_lock){.-.-..}, at: [<00000000004902f6>] zfcp_erp_modify_adapter_status+0x9e/0x16c
[...]

To stop this warning, change the request queue lock to disable irqs,
not only softirq. The changes are required only outside of the
critical "send fcp command" path.

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>
2010-09-16 22:54:19 -04:00
Christof Schmitt
b62a8d9b45 [SCSI] zfcp: Use SCSI device data zfcp_scsi_dev instead of zfcp_unit
This is the large change to switch from using the data in
zfcp_unit to zfcp_scsi_dev. Keeping everything working requires doing
the switch in one piece. To ensure that no code keeps using the data
in zfcp_unit, this patch also removes the data from zfcp_unit that is
now being replaced with zfcp_scsi_dev.

For zfcp, the scsi_device together with zfcp_scsi_dev exist from the
call of slave_alloc to the call of slave_destroy. The data in
zfcp_scsi_dev is initialized in zfcp_scsi_slave_alloc and the LUN is
opened; the final shutdown for the LUN is run from slave_destroy.

Where the scsi_device or zfcp_scsi_dev is needed, the pointer to the
scsi_device is passed as function argument and inside the function
converted to the pointer to zfcp_scsi_dev; this avoids back and forth
conversion betweeen scsi_device and zfcp_scsi_dev.

While changing the function arguments from zfcp_unit to scsi_device,
the functions names are renamed form "unit" to "lun". This is to have
a seperation between zfcp_scsi_dev/LUN and the zfcp_unit; only code
referring to the remaining configuration information in zfcp_unit
struct uses "unit".

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>
2010-09-16 22:54:17 -04:00
Christof Schmitt
339f4f4eab [SCSI] zfcp: Trigger logging in the FCP channel on qdio error conditions
Exploit the cio siosl function to trigger logging in the FCP channel
on qdio error conditions. Add a helper function in zfcp_qdio to ensure
that tracing is only triggered once before calling qdio_shutdown.

Trigger in zfcp for hardware logs are:
 - timeout for FSF requests to the FCP channel
 - "no recommendation" status from FCP channel
 - invalid FSF protocol status
 - stalled outbound queue
 - unknown request id on inbound queue
 - QDIO_ERROR_SLSB_STATE

All of the above triggers run from the Linux qdio softirq context, so
no additional synchronization is necessary for the handling of the
ZFCP_STATUS_ADAPTER_SIOSL_ISSUED flag.

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>
2010-07-28 09:48:58 -05:00
Felix Beck
ef3eb71d8b [SCSI] zfcp: Introduce experimental support for DIF/DIX
Introduce support for DIF/DIX in zfcp: Report the capabilities for the
Scsi_host, map the protection data when issuing I/O requests and
handle the new error codes. Also add the fsf data_direction field to
the hba trace, it is useful information for debugging in that area.
This is an EXPERIMENTAL feature for now.

Signed-off-by: Felix Beck <felix.beck@de.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2010-07-28 09:48:56 -05:00
Sven Schuetz
2d1e547f75 [SCSI] zfcp: Post events through FC transport class
Post FC transport class netlink events for usage in the userspace,
e.g. for HBAAPI. Supported events are those required for the
polled events in HBAAPI.
- link up
- link down
- incoming RSCN
(events related to FC-AL are not supported, as zfcp has no support for FC-AL)

Signed-off-by: Sven Schuetz <sven@linux.vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2010-07-28 09:48:52 -05:00
Swen Schillig
706eca49a0 [SCSI] zfcp: Cleanup QDIO attachment and improve processing.
Some definitions and structures in the zfcp QDIO processing are
improved by the removal of not required variables and processing steps.
I addition the naming of some variables is changed to make their purpose
more clear.

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>
2010-07-28 09:48:50 -05:00
Swen Schillig
01b047599a [SCSI] zfcp: Cleanup function parameters for sbal value.
A lot of functions require the amount of SBALs as one of their
parameter which is most times invariable.  Therefore remove this
parameter and set the SBAL value explicitly if a non standard value is
required.  In addition the warning message "oversized data" is
replaced with a BUG_ON() statement assuring the limits defined and
requested by zfcp.

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>
2010-07-28 09:48:49 -05:00
Christof Schmitt
faf4cd8542 [SCSI] zfcp: Use correct width for timer_interval field
The timer_interval is 14 bits in width. Introduce a define for
properly masking the value.

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>
2010-07-28 09:48:48 -05:00
Christof Schmitt
8d88cf3f3b [SCSI] zfcp: Update status read mempool
Commit 64deb6efdc changed the way status
read buffers are handled but forgot to adjust the mempool to the new
size. Add the call to resize the mempool after the exchange config
data. Also use the define instead of the hard coded number in the fsf
callback for consistency.

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>
2010-07-21 15:05:09 -07:00
Christof Schmitt
c2af7545aa [SCSI] zfcp: Do not wait for SBALs on stopped queue
Trying to read the FC host statistics on an offline adapter results in
a 5 seconds wait. Reading the statistics tries to issue an exchange
port data request which first waits up to 5 seconds for an entry in
the request queue.

Change the strategy for getting a free SBAL to exit when the queue is
stopped. Reading the statistics will then fail without the wait.

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>
2010-07-21 15:05:07 -07:00
Swen Schillig
30b6777b89 [SCSI] zfcp: Fix check whether unchained ct_els is possible
A false check was performed whether an unchained ct_els
is possible or not.

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>
2010-07-21 15:05:06 -07:00
James Bottomley
95bb335c0e [SCSI] Merge scsi-misc-2.6 into scsi-rc-fixes-2.6
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2010-05-18 10:37:41 -04:00
Christof Schmitt
64deb6efdc [SCSI] zfcp: Use status_read_buf_num provided by FCP channel
The FCP channel provides the number of status read buffers to issue.
Use the provided number instead of the hardcoded number in zfcp.

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>
2010-05-02 15:42:33 -04:00
Christof Schmitt
6b9e152009 [SCSI] zfcp: Move sbal_get function to zfcp_qdio.c
Waiting for a free sbal is a operation on the qdio queue. Move the
code implementing the wait to zfcp_qdio.c and rename the functions
accordingly.

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>
2010-05-02 15:42:32 -04:00
Christof Schmitt
1674b40547 [SCSI] zfcp: Move sbale handling to zfcp_qdio files
Move the code accessing the qdio sbales and zfcp_qdio_req struct to
the zfcp_qdio files and provide helper functions for accessing the
qdio related parts.

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>
2010-05-02 15:42:30 -04:00