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path: root/drivers/s390/block/dasd.c
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2017-01-31s390/dasd: check blockdevice pointer before trying to sync blockdeviceStefan Haberland
If safe offline is called for a DASD alias device a null pointer is passed to fsync_bdev. So check for existence of the blockdevice before calling fsync_bdev. Should not be a real world problem since safe offline for an alias device does not make sense and fsync_bdev can deal with a NULL pointer which it gets after successful NULL pointer dereferencing on s390. Signed-off-by: Stefan Haberland <sth@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-01-31s390/dasd: check for device error pointer within state change interruptsStefan Haberland
Check if the device pointer is valid. Just a sanity check since we already are in the int handler of the device. Signed-off-by: Stefan Haberland <sth@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-12-12s390/dasd: channel path aware error recoveryStefan Haberland
With this feature, the DASD device driver more robustly handles DASDs that are attached via multiple channel paths and are subject to constant Interface-Control-Checks (IFCCs) and Channel-Control-Checks (CCCs) or loss of High-Performance-FICON (HPF) functionality on one or more of these paths. If a channel path does not work correctly, it is removed from normal operation as long as other channel paths are available. All extended error recovery states can be queried and reset via user space interfaces. Signed-off-by: Stefan Haberland <sth@linux.vnet.ibm.com> Reviewed-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Reviewed-by: Jan Hoeppner <hoeppner@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-12-12s390/dasd: extend dasd path handlingStefan Haberland
Store flags and path_data per channel path. Implement get/set functions for various path masks. The patch does not add functional changes. Signed-off-by: Stefan Haberland <sth@linux.vnet.ibm.com> Reviewed-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Reviewed-by: Jan Hoeppner <hoeppner@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-10-28s390/dasd: Eliminate race condition in dasd_generic_set_offline()Jan Höppner
Before we set a device offline, the open_count for the block device is checked and certain flags are checked and set as well. However, this is all done without holding any lock. Potentially, if the open_count was checked but the DASD_FLAG_OFFLINE wasn't set yet, a different process might want to increase the open_count depending on whether DASD_FLAG_OFFLINE is set or not in the meanwhile. This is quite racy and can lead to the loss of the device for that process and subsequently lead to a panic. Fix this by checking the open_count and setting the offline flags while holding the ccwdev lock. Reviewed-by: Stefan Haberland <sth@linux.vnet.ibm.com> Signed-off-by: Jan Höppner <hoeppner@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-10-28s390/dasd: Define often used variableJan Höppner
block->request_queue is used many times in dasd_setup_queue. Define a separate variable to increase readability a bit and to make it better reusable. Reviewed-by: Stefan Haberland <sth@linux.vnet.ibm.com> Signed-off-by: Jan Höppner <hoeppner@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-10-28s390/dasd: Make setting queue_max_segments more explicitJan Höppner
Currently the block queue value max_segments is set to -1L, which is then implicitly casted to unsigned short in blk_queue_max_segments. This results in 65535 (64k) max_segments. Even though the resulting value is correct, setting it implicitly using -1L is rather confusing. Set the value explicitly using the USHRT_MAX macro instead. Reviewed-by: Stefan Haberland <sth@linux.vnet.ibm.com> Signed-off-by: Jan Höppner <hoeppner@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-09-26s390/dasd: fix panic during offline processingStefan Haberland
A DASD device consists of the device itself and a discipline with a corresponding private structure. These fields are set up during online processing right after the device is created and before it is processed by the state machine and made available for I/O. During offline processing the discipline pointer and the private data gets freed within the state machine and without protection of the existing reference count. This might lead to a kernel panic because a function might have taken a device reference and accesses the discipline pointer and/or private data of the device while this is already freed. Fix by freeing the discipline pointer and the private data after ensuring that there is no reference to the device left. Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Signed-off-by: Stefan Haberland <sth@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-09-26s390/dasd: fix hanging offline processingStefan Haberland
Internal I/O is processed by the _sleep_on_function which might wait for a device to get operational. During offline processing this will never happen and therefore the refcount of the device will not drop to zero and the offline processing blocks as well. Fix by letting requests fail in the _sleep_on function during offline processing. No further handling of the requests is necessary since this is internal I/O and the device is thrown away afterwards. Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Signed-off-by: Stefan Haberland <sth@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-09-20s390/dasd: add missing KOBJ_CHANGE event for unformatted devicesStefan Haberland
The DASD device driver throws change events for the DASD blockdevice after the online processing is done so that udev rules can take actions after it. The change event was missing for unformatted devices. Signed-off-by: Stefan Haberland <sth@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-08-10s390/dasd: fix hanging device after clear subchannelStefan Haberland
When a device is in a status where CIO has killed all I/O by itself the interrupt for a clear request may not contain an irb to determine the clear function. Instead it contains an error pointer -EIO. This was ignored by the DASD int_handler leading to a hanging device waiting for a clear interrupt. Handle -EIO error pointer correctly for requests that are clear pending and treat the clear as successful. Signed-off-by: Stefan Haberland <sth@linux.vnet.ibm.com> Reviewed-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Cc: stable@vger.kernel.org Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-04-15s390/dasd: Add new ioctl BIODASDCHECKFMTJan Höppner
Implement new DASD IOCTL BIODASDCHECKFMT to check a range of tracks on a DASD volume for correct formatting. The following characteristics are checked: - Block size - ECKD key length - ECKD record ID - Number of records per track Signed-off-by: Jan Höppner <hoeppner@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-04-15s390/dasd: add query host access to volume supportStefan Haberland
With this feature, applications can query if a DASD volume is online to another operating system instances by checking the online status of all attached hosts from the storage server. Reviewed-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-02-17s390/dasd: fix performance dropStefan Haberland
Commit ca369d51b ("sd: Fix device-imposed transfer length limits") introduced a new queue limit max_dev_sectors which limits the maximum sectors for requests. The default value leads to small dasd requests and therefor to a performance drop. Set the max_dev_sectors value to the same value as the max_hw_sectors to use the maximum available request size for DASD devices. Signed-off-by: Stefan Haberland <sth@linux.vnet.ibm.com> Cc: stable@vger.kernel.org # 4.4+ Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-12-30s390/dasd: fix failfast for disconnected devicesStefan Haberland
Enabling failfast should let request fail immediately if either an error occurred or the device gets disconnected. For disconnected devices new requests are not fetches from the block queue and therefore failfast is not triggered. Fix by letting the DASD driver fetch requests for disconnected devices with failfast active. Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14s390/dasd: mark DASD devices as non rotationalChristian Borntraeger
We were able to reduce the CPU overhead of big paging scenarios when announcing our paging disks as non-rotational. Almost all dasd devices are implemented in storage servers with cache, raid, striping and lots of magic. There is no point in optimizing the disk schedulers and swap code for a single platter moving arm rotational disks. Given the complexity of the setup and the fact that this change is mostly to disable the additional overhead in swap code, lets keep the other functionality unchanged and do not disable the this device as entropy source - unlike other non-rotational devices. Suggested-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-07-13s390/dasd: fix kernel panic when alias is set offlineStefan Haberland
The dasd device driver selects which (alias or base) device is used for a given requests when the request is build. If the chosen alias device is set offline before the request gets queued to the device queue the starting function may use device structures that are already freed. This might lead to a hanging offline process or a kernel panic. Add a check to the starting function that returns the request to the upper layer if the device is already in offline processing. In addition to that prevent that an alias device that's already in offline processing gets chosen as start device. Reviewed-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Reviewed-by: Peter Oberparleiter <peter.oberparleiter@linux.vnet.ibm.com> Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-05-13s390/dasd: Enable automatic loading of dasd_diag_modPeter Oberparleiter
Enabling a DASD that was configured to use the DIAG250 access method while the corresponding kernel module dasd_diag_mod has not been loaded fails with an error message. To fix this, users need to manually load the dasd_diag_mod module. This procedure can be simplified by automatically loading the dasd_diag_mod from within the kernel when a DASD configured for DIAG250 is set online. Signed-off-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-04-15s390/dasd: Fix unresumed device after suspend/resume having no pathsStefan Haberland
The DASD device driver prevents I/O from being started on stopped devices. This also prevented channel paths to be verified and so the device was unable to be resumed. Fix by allowing path verification requests on stopped devices. Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-04-15s390/dasd: fix unresumed device after suspend/resumeStefan Haberland
The DASD device driver only has a limited amount of memory to build I/O requests. This memory was used by blocklayer requests leading to an inability to build needed internal requests to resume the device. Fix by preventing the DASD driver to fetch requests for a stopped device. Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com> Reference-ID: RQM 2520 Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-04-15s390/dasd: fix inability to set a DASD device offlineStefan Haberland
Fix ref counting for DASD devices leading to an inability to set a DASD device offline. Before a worker is scheduled the DASD device driver takes a reference to the device. If the worker was already scheduled this reference was never freed. Fix by giving the reference to the DASD device free when schedule_work() returns false. Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-03-25s390/dasd: remove setting of scheduler from driverStefan Haberland
Remove the hard coded scheduler for the DASD device driver to enable change of the scheduler during runtime. Set recommended deadline scheduler via additional udev rule. Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-03-25s390: remove 31 bit supportHeiko Carstens
Remove the 31 bit support in order to reduce maintenance cost and effectively remove dead code. Since a couple of years there is no distribution left that comes with a 31 bit kernel. The 31 bit kernel also has been broken since more than a year before anybody noticed. In addition I added a removal warning to the kernel shown at ipl for 5 minutes: a960062e5826 ("s390: add 31 bit warning message") which let everybody know about the plan to remove 31 bit code. We didn't get any response. Given that the last 31 bit only machine was introduced in 1999 let's remove the code. Anybody with 31 bit user space code can still use the compat mode. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-01-29s390/dasd: cleanup profilingSebastian Ott
The dasd driver has a lot of duplicated code to handle dasd_global_profile. With this patch we use the same code for the global and the per device profiling data. Note that dasd_stats_write had to change slightly to maintain some odd differences between A) per device and global profile and B) proc and sysfs interface usage. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Reviewed-by: Stefan Haberland <stefan.haberland@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-01-29s390/dasd: add locking for global_profile accessSebastian Ott
Access to DASDs global statistics is done without locking which can lead to inconsistent data. Add locking to fix this. Also move the relevant structs in a global dasd_profile struct. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Reviewed-by: Stefan Haberland <stefan.haberland@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-11-28s390/dasd: fix list corruption for sleep_on requestsStefan Haberland
Fix race for sleep_on requests leading to list corruption. The SLEEP_ON_END_TAG is set during CQR clean up. Remove it from interrupt handler to avoid the CQR from being cleared when it is still in the device_queue. Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-11-28s390/dasd: fix infinite term I/O loopStefan Haberland
During device activation all paths could be lost and since the device is not active it has no indication of this fact - hence the CQR will time-out. The following cancelation might fail with -EINVAL because CIO took over control and started path verification. In this case mark the CQR as being CLEARED since it could not be running any more. Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-11-28s390/dasd: remove unused codeStefan Haberland
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-10-09s390/dasd: add support for control unit initiated reconfigurationStefan Haberland
Add support for Control Unit Initiated Reconfiguration (CUIR) to Linux, a storage server interface to reconcile concurrent hardware changes between storage and host. Reviewed-by: Stefan Weinhuber <wein@de.ibm.com> Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-10-09s390/dasd: fix infinite loop during formatStefan Haberland
Error recovery requests may not be cleaned up correctly so that other needed erp requests can not be build because of insufficient memory. This would lead to an infinite loop trying to build erp requests. Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-07-22dasd: fix error recovery for alias devices during formatStefan Haberland
Kernel panic or a hanging device during format if an alias device is set offline or I/O errors occur. Omit the error recovery procedure for alias devices and do retries on the base device with full erp. Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-07-22dasd: fix list_del corruption during formatStefan Haberland
If I/O errors occur during format a kernel panic with a list_del corruption may occur. Stop error recovery procedure after an erp action was taken. Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-07-22dasd: fix unresponsive device during formatStefan Haberland
If path events occur the formatting process stucks because path events may flush format requests from the queue. Kick the format process after path events are handled. Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-07-22dasd: use aliases for formatted devices during formatStefan Haberland
Formatting of a previously formatted device is slower than newly format a device when alias devices are available. For already formatted devices the alias devices are not used for formatting. Fix the alias handling for already formatted devices. Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-07-22s390/dasd: replace seq_printf by seq_putsFabian Frederick
Fix checkpatch warnings: "WARNING: Prefer seq_puts to seq_printf" Signed-off-by: Fabian Frederick <fabf@skynet.be> Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-07-22s390/dasd: replace pr_warning by pr_warnFabian Frederick
Fix checkpatch warning: "WARNING: Prefer pr_warn(... to pr_warning(..." + coalesce formats. Signed-off-by: Fabian Frederick <fabf@skynet.be> Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-07-22s390/dasd: Move EXPORT_SYMBOL after function/variableFabian Frederick
Fix checkpatch warnings: "WARNING: EXPORT_SYMBOL(foo); should immediately follow its function/variable" Signed-off-by: Fabian Frederick <fabf@skynet.be> Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-07-22s390/dasd: remove unnecessary null test before debugfs_removeFabian Frederick
This fixes checkpatch warning: "WARNING: debugfs_remove(NULL) is safe this check is probably not required" Signed-off-by: Fabian Frederick <fabf@skynet.be> Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-01-16s390: Fix misspellings using 'codespell' toolHendrik Brueckner
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-11-14Merge branch 'for-3.13/drivers' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block driver updates from Jens Axboe: "This is the block driver pull request for 3.13. As with the core pull request just sent out, this was rebased on top of the core branch again after the immutable series was pulled. This also means that bcache gets to sit the initial pull over. I will send a second driver pull request in the merge window to get those fixes in, once they have been rebased and tested on top of the non-immutable stack. This pull request contains: - Add support for the sTec Kronos pci-e flash card from sTec. Also has various cleanups for this driver, from myself, Bart, Mike Snizter, and Wei Yongjun. - Add surprise removal support for the micron mtip32xx driver from Micron. - Floppy documentation fix from Ben Harris. - debugfs bug fix for pktcdvd from Dan Carpenter. - Fix for the mtip32xx driver stack usage in the debugfs path, dynamically allocating those buffers instead. From David Milburn. - Disable cpqarray in Kconfig. The plan is to remove it on request of HP, but lets disable it for a few revisions just to see if anyone yells. - drbd fixes from Lars Ellenberg and Philipp Reisner. - Elevator switch fix for the s390 block driver from Heiko Carstens. - loop crash fix on IO to unassigned device from Mikulas Patocka. - A series of bug fixes for the IBM rsxx pci-e flash driver from Philip J Kelleher. - cciss probe fix from Stephen Cameron. - Xen block front/back fixes from Roger Pau Monne and Vegard Nossum" * 'for-3.13/drivers' of git://git.kernel.dk/linux-block: (41 commits) floppy: Correct documentation of driver options when used as a module. pktcdvd: debugfs functions return NULL on error xen-blkfront: restore the non-persistent data path skd: fix formatting in skd_s1120.h skd: reorder construct/destruct code skd: cleanup skd_do_inq_page_da() skd: remove SKD_OMIT_FROM_SRC_DIST ifdefs skd: remove redundant skdev->pdev assignment from skd_pci_probe() skd: use <asm/unaligned.h> skd: remove SCSI subsystem specific includes skd: register block device only if some devices are present skd: fix error messages in skd_init() skd: fix error paths in skd_init() skd: fix unregister_blkdev() placement skd: more removal of bio-based code skd: cleanup the skd_*() function block wrapping skd: rip out bio path skd: fix error return code in skd_pci_probe() s390/dasd: hold request queue sysfs lock when calling elevator_init() cciss: return 0 from driver probe function on success, not 1 ...
2013-11-08s390/dasd: hold request queue sysfs lock when calling elevator_init()Heiko Carstens
"elevator: Fix a race in elevator switching and md device initialization" changed the semantics of elevator_init() in a way that now enforces to hold the corresponding request queue's sysfs_lock when calling elevator_init() to fix a race. The patch did not convert the s390 dasd device driver which is the only device driver which also calls elevator_init(). So add the missing locking. Cc: Tomoki Sekiyama <tomoki.sekiyama@hds.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2013-10-28s390/dasd: Write to profile data area only if it is availableStefan Weinhuber
We check for the existence of block->profile.data before we write to it, but the dependent code block misses braces. Signed-off-by: Stefan Weinhuber <wein@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-07-30s390/dasd: fix hanging devices after path eventsStefan Haberland
The processing of the dasd_block tasklet may have been interrupted by a path event. Restart the dasd tasklets in sleep_on_immediately function. Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-07-01s390/dasd: Fail all requests when DASD_FLAG_ABORTIO is setHannes Reinecke
Whenever a DASD request encounters a timeout we might need to abort all outstanding requests on this or even other devices. This is especially useful if one wants to fail all devices on one side of a RAID10 configuration, even though only one device exhibited an error. To handle this I've introduced a new device flag DASD_FLAG_ABORTIO. This flag is evaluated in __dasd_process_request_queue() and will invoke blk_abort_request() for all outstanding requests with DASD_CQR_FLAGS_FAILFAST set. This will cause any of these requests to be aborted immediately if the blk_timeout function is activated. The DASD_FLAG_ABORTIO is also evaluated in __dasd_process_request_queue to abort all new request which would have the DASD_CQR_FLAGS_FAILFAST bit set. The flag can be set with the new ioctls 'BIODASDABORTIO' and removed with 'BIODASDALLOWIO'. Signed-off-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Stefan Weinhuber <wein@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-07-01s390/dasd: Add 'timeout' attributeHannes Reinecke
This patch adds a 'timeout' attibute to the DASD driver. When set to non-zero, the blk_timeout function will be enabled with the timeout specified in the attribute. Setting 'timeout' to '0' will disable block timeouts. Signed-off-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Stefan Weinhuber <wein@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-07-01block/dasd: detailed I/O errorsHannes Reinecke
The DASD driver is using FASTFAIL as an equivalent to the transport errors in SCSI. And the 'steal lock' function maps roughly to a reservation error. So we should be returning the appropriate error codes when completing a request. Acked-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Stefan Weinhuber <wein@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-07-01s390/dasd: Implement block timeout handlingHannes Reinecke
This patch implements generic block layer timeout handling callbacks for DASDs. When the timeout expires the respective cqr is aborted. With this timeout handler time-critical request abort is guaranteed as the abort does not depend on the internal state of the various DASD driver queues. Signed-off-by: Hannes Reinecke <hare@suse.de> Acked-by: Stefan Weinhuber <wein@de.ibm.com> Signed-off-by: Stefan Weinhuber <wein@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-07-01s390/dasd: process all requests in the device taskletHannes Reinecke
Originally the DASD device tasklet would process the entries on the ccw_queue until the first non-final request was found. Which was okay as long as all requests have the same retries and expires parameter. However, as we're now allowing to modify both it is possible to have requests _after_ the first request which already have expired. So we need to check all requests in the device tasklet. Signed-off-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Stefan Weinhuber <wein@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-07-01s390/dasd: Clarify commentHannes Reinecke
dasd_cancel_req will never return 1, only 0. Signed-off-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Stefan Weinhuber <wein@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-05-31s390/dasd: fix handling of gone pathsStefan Weinhuber
When a path is gone and dasd_generic_path_event is called with a PE_PATH_GONE event, we must assume that any I/O request on that subchannel is still running. This is unlike the dasd_generic_notify handler and the CIO_NO_PATH event, which implies that the subchannel has been cleared. If dasd_generic_path_event finds that the path has been the last usable path, it must not call dasd_generic_last_path_gone (which would reset the state of running requests), but just set the DASD_STOPPED_DC_WAIT bit. Signed-off-by: Stefan Weinhuber <wein@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>