In z/VM it is possible to attach a device as read-only. To prevent
unintentional write requests and subsequent I/O errors, we can detect
this configuration using the z/VM DIAG 210 interface and set the
respective linux block device to read-only as well.
Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Remove the PSF order/suborder check from the Symmetrix CKD dasd ioctl.
In exchange restrict the ioctl to CAP_SYS_ADMIN and CAP_SYS_RAWIO.
Signed-off-by: Nigel Hislop <hislop_nigel@emc.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* 'for-2.6.34' of git://git.kernel.dk/linux-2.6-block: (38 commits)
block: don't access jiffies when initialising io_context
cfq: remove 8 bytes of padding from cfq_rb_root on 64 bit builds
block: fix for "Consolidate phys_segment and hw_segment limits"
cfq-iosched: quantum check tweak
blktrace: perform cleanup after setup error
blkdev: fix merge_bvec_fn return value checks
cfq-iosched: requests "in flight" vs "in driver" clarification
cciss: Fix problem with scatter gather elements in the scsi half of the driver
cciss: eliminate unnecessary pointer use in cciss scsi code
cciss: do not use void pointer for scsi hba data
cciss: factor out scatter gather chain block mapping code
cciss: fix scatter gather chain block dma direction kludge
cciss: simplify scatter gather code
cciss: factor out scatter gather chain block allocation and freeing
cciss: detect bad alignment of scsi commands at build time
cciss: clarify command list padding calculation
cfq-iosched: rethink seeky detection for SSDs
cfq-iosched: rework seeky detection
block: remove padding from io_context on 64bit builds
block: Consolidate phys_segment and hw_segment limits
...
Flushing the dasd ccw request queue may stop the processing of the
block device request queue. Destroy partitions may wait for
outstanding requests and thus hang.
Swapping dasd_destroy_partitions and dasd_flush_request_queue so that
the request queue is empty before dasd_destroy_partitions is called.
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The function dasd_device_from_cdev returns a reference to the dasd
device and increases the refcount by one. If an exception occurs,
the refcount was not decreased in all cases
e.g. in dasd_discipline_show.
Prevent the offline processing from hang by correcting two functions
to decrease the refcount even if an error occured.
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Setting a DASD online and offline in quick succession may cause
a kernel panic or let the chhccwdev command wait forever.
The Online process is split into two parts. After the first part
is finished the offline process may be called. This may result
in a situation where the second online processing part tries to
set the DASD offline as well.
Use a mutex to protect online and offline against each other.
Also correct some checking.
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Except for SCSI no device drivers distinguish between physical and
hardware segment limits. Consolidate the two into a single segment
limit.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
The block layer calling convention is blk_queue_<limit name>.
blk_queue_max_sectors predates this practice, leading to some confusion.
Rename the function to appropriately reflect that its intended use is to
set max_hw_sectors.
Also introduce a temporary wrapper for backwards compability. This can
be removed after the merge window is closed.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Fix possible NULL pointer in DASD messages and correct discipline
checking.
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The DIAG discipline does not have a own driver name. It shows up as
dasd-eckd or dasd-fba. So messages for dasd-diag are moved to the
generic dasd part.
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Makes use of skip_spaces() defined in lib/string.c for removing leading
spaces from strings all over the tree.
It decreases lib.a code size by 47 bytes and reuses the function tree-wide:
text data bss dec hex filename
64688 584 592 65864 10148 (TOTALS-BEFORE)
64641 584 592 65817 10119 (TOTALS-AFTER)
Also, while at it, if we see (*str && isspace(*str)), we can be sure to
remove the first condition (*str) as the second one (isspace(*str)) also
evaluates to 0 whenever *str == 0, making it redundant. In other words,
"a char equals zero is never a space".
Julia Lawall tried the semantic patch (http://coccinelle.lip6.fr) below,
and found occurrences of this pattern on 3 more files:
drivers/leds/led-class.c
drivers/leds/ledtrig-timer.c
drivers/video/output.c
@@
expression str;
@@
( // ignore skip_spaces cases
while (*str && isspace(*str)) { \(str++;\|++str;\) }
|
- *str &&
isspace(*str)
)
Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com>
Cc: Julia Lawall <julia@diku.dk>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Neil Brown <neilb@suse.de>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Cc: David Howells <dhowells@redhat.com>
Cc: <linux-ext4@vger.kernel.org>
Cc: Samuel Ortiz <samuel@sortiz.org>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The first DASD that is set online for a specific logical control unit
has to do certain setup steps on the storage server to make full use
of it, for example it will enable PAV.
The features and characteristics reported by the storage server will
depend on this setup, so all other devices on the same LCU will need
to wait for the setup to be finished.
Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Remove strings from s390 debugfeature entries that could lead to a
crash when the data is read from dbf because the strings do not exist
any more.
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Most of the error conditions reported by a FICON storage server
indicate situations which can be recovered. Sometimes the host just
needs to retry an I/O request, but sometimes the recovery
is more complex and requires the device driver to wait, choose
a different path, etc.
The DASD device driver has a fully featured error recovery
for normal block layer I/O, but not for internal I/O request which
are for example used during the device bring up.
This can lead to situations where the IPL of a system fails because
DASD devices are not properly recognized.
This patch will extend the internal I/O handling to use the existing
error recovery procedures.
Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The DASD device driver needs to explicitly enable the prefix command
on the storage server, before it can be used. Originally we enabled
this command along with others only if we wanted to support PAV.
However, today we require this command for other features like
High Performance FICON as well, so we need to always enable prefix.
Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
the todclk.h header file is dead code. Remove it.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
When a DASD device is used with the DIAG discipline, the DIAG
initialization will indicate success or error with a respective
return code. So far we have interpreted a return code of 4 as error,
but it actually means that the initialization was successful, but
the device is read-only. To allow read-only devices to be used with
DIAG we need to accept a return code of 4 as success.
Re-initialization of the DIAG access is also part of the DIAG error
recovery. If we find that the access mode of a device has been
changed from writable to read-only while the device was in use,
we print an error message.
Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Split setting (driver wants feature enabled) and status (feature
setup was successful) for PGID related ccw device features so that
setup errors can be detected. Previously, incorrectly handled setup
errors could in rare cases lead to erratic I/O behavior and
permanently unusuable devices.
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
If the rdc_buffer is above 2G we need indirect addresssing so we have
to use an idaw to give the rdc_buffer to the ccw.
If the rdc_buffer is under 2G nothing changes.
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Replace spin_lock with spin_lock_irqsave in dasd_eckd_restore_device.
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
There is a race while re-reading the device characteristics. After
cleaning the memory area a cqr is build which reads the device
characteristics. This may take a rather long time and the device
characteristics structure is zero during this. Now it could be
possible that the block tasklet starts working and a new cqr will be
build. The build_cp command refers to the device characteristics
structure and this may lead into a divide by zero exception.
Fix this by re-reading the device characteristics into a temporary
structur and copy the data to the original structure. Also take the
ccwdev_lock.
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6: (22 commits)
[S390] Update default configuration.
[S390] hibernate: Do real CPU swap at resume time
[S390] dasd: tolerate devices that have no feature codes
[S390] zcrypt: Do not add/remove devices in s/r callbacks
[S390] hibernate: make sure pfn_is_nosave handles lowcore pages
[S390] smp: introduce LC_ORDER and simplify lowcore handling
[S390] ptrace: use common code for simple peek/poke operations
[S390] fix disabled_wait inline assembly clobber list
[S390] Change kernel_page_present coding style.
[S390] hibernation: reset system after resume
[S390] hibernation: fix guest page hinting related crash
[S390] Get rid of init_module/delete_module compat functions.
[S390] Convert sys_execve to function with parameters.
[S390] Convert sys_clone to function with parameters.
[S390] qdio: change state of all primed input buffers
[S390] qdio: reduce per device debug messages
[S390] cio: introduce consistent subchannel scanning
[S390] cio: idset use actual number of ssids
[S390] cio: dont kfree vmalloced memory
[S390] cio: introduce css_settle
...
The DASD device driver reads the feature codes of a device during
device initialization. These codes are later used to determine the
availability of advanced features like PAV or High Performance FICON.
Some very old devices do not support the command to read feature
codes and the initialization routine fails.
As the feature codes are not necessary for basic DASD operations, we
can support such devices by just ignoring missing feature codes.
Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (34 commits)
trivial: fix typo in aic7xxx comment
trivial: fix comment typo in drivers/ata/pata_hpt37x.c
trivial: typo in kernel-parameters.txt
trivial: fix typo in tracing documentation
trivial: add __init/__exit macros in drivers/gpio/bt8xxgpio.c
trivial: add __init macro/ fix of __exit macro location in ipmi_poweroff.c
trivial: remove unnecessary semicolons
trivial: Fix duplicated word "options" in comment
trivial: kbuild: remove extraneous blank line after declaration of usage()
trivial: improve help text for mm debug config options
trivial: doc: hpfall: accept disk device to unload as argument
trivial: doc: hpfall: reduce risk that hpfall can do harm
trivial: SubmittingPatches: Fix reference to renumbered step
trivial: fix typos "man[ae]g?ment" -> "management"
trivial: media/video/cx88: add __init/__exit macros to cx88 drivers
trivial: fix typo in CONFIG_DEBUG_FS in gcov doc
trivial: fix missing printk space in amd_k7_smp_check
trivial: fix typo s/ketymap/keymap/ in comment
trivial: fix typo "to to" in multiple files
trivial: fix typos in comments s/DGBU/DBGU/
...
Currently in the suspend process checksums for the XPRAM partitions are
created and stored. During the resume process it is checked,
if the checksums are still the same. If this is not the case, a kernel panic
is triggered. Unfortunately this prevents XPRAM from beeing used as suspend
device, because in this case after the checksum has been created, the
memory image is written to XPRAM and therefore the contents of the suspend
partition is changed. In order to allow XPRAM to be used as suspend device,
this patch removes the checksum validation.
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This patch fixes message naming so that generic dasd messages do not
contain the device discipline. For this purpose the dev_ makros are
replaced by pr_ makros for generic dasd messages.
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
A DASD device that is not ready or online has no defined disk layout,
so all requests that arrive in such a state need to be returned as
failed.
Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
If the NULL test on block is needed, it should be before the dereference of
the base field.
The semantic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)
// <smpl>
@r@
expression E1,E2;
identifier fld;
statement S1,S2;
@@
E1 = E2->fld;
(
if (E1 == NULL) S1 else S2
|
*if (E2 == NULL) S1 else S2
)
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* Remove smp_lock.h from files which don't need it (including some headers!)
* Add smp_lock.h to files which do need it
* Make smp_lock.h include conditional in hardirq.h
It's needed only for one kernel_locked() usage which is under CONFIG_PREEMPT
This will make hardirq.h inclusion cheaper for every PREEMPT=n config
(which includes allmodconfig/allyesconfig, BTW)
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
From: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
remove loop, add some debug data and use get_sense function
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
To set a dasd online dasd_change_state is called twice. The first
cycle will schedule initial analysis of the device, set the rc to
-EAGAIN and will not touch the device state any more.
The initial analysis will in turn call dasd_change_state to increase
the state to the final DASD_STATE_ONLINE.
If the dasd_change_state on the second thread outruns the other one
both finish with the state set to DASD_STATE_ONLINE and the device
refcount will be decreased by 2.
Fix this by leaving dasd_change_state on rc == -EAGAIN so that the
refcount will always be decreased by 1.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The stop flags are handled in the generic restore function so the
stop flag is removed also for FBA and DIAG devices.
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Introduce the power management callbacks to the dasd driver. On suspend
the dasd devices are stopped and removed from the focus of alias
management.
On resume they are reinitialized by rereading the device characteristics
and adding the device to the alias management.
In case the device has gone away during suspend it will caught in the
suspend state with stopped flag set to UNRESUMED. After it appears again
the restore function is called again.
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
If a DASD requests is started with dasd_sleep_on and fails, then the
calling function may need to know the reason for the failure.
In cases of hardware errors it can inspect the sense data in the irb,
but when the reason is internal (e.g. start_IO failed) then it needs
a meaningfull return code.
Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Some functions called as a late_initcall depend on completely
initialized devices. Since commit
f3445a1a65 the dasd driver uses the
new async framework and relies on the fact that synchronization is
done in prepare_namespace which is called after the late_initcalls.
Fix this by calling async_synchronize_full at the end of the related
init functions.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Fix a broken memset (sizeof pointer vs sizeof the underlying
structure) by cleaning up the involved functions.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Stefan Weinhuber