kernel.git/drivers/s390/block/dasd_alias.c, branch linux-5.7.y

s390/dasd: fix endless loop after read unit address configuration

2019-08-02T02:46:14Z

After getting a storage server event that causes the DASD device driver to update its unit address configuration during a device shutdown there is the possibility of an endless loop in the device driver. In the system log there will be ongoing DASD error messages with RC: -19. The reason is that the loop starting the ruac request only terminates when the retry counter is decreased to 0. But in the sleep_on function there are early exit paths that do not decrease the retry counter. Prevent an endless loop by handling those cases separately. Remove the unnecessary do..while loop since the sleep_on function takes care of retries by itself. Fixes: 8e09f21574ea ("[S390] dasd: add hyper PAV support to DASD device driver, part 1") Cc: stable@vger.kernel.org # 2.6.25+ Signed-off-by: Stefan Haberland Reviewed-by: Jan Hoeppner Signed-off-by: Jens Axboe

s390/dasd: fix gcc 8 stringop-truncation warning

2018-07-02T09:24:53Z

drivers/s390/block/dasd_alias.c:711:2: warning: 'strncpy' output truncated before terminating nul copying 4 bytes from a string of the same length [-Wstringop-truncation] strncpy((char *) &cqr->magic, "ECKD", 4); Replace strncpy to int as a buffer with memcpy. Acked-by: Stefan Haberland Reviewed-by: Heiko Carstens Signed-off-by: Vasily Gorbik Signed-off-by: Martin Schwidefsky

s390/dasd: only use preallocated requests

2018-06-12T13:14:31Z

Change the remaining users of dasd_kmalloc_request to use preallocated memory and remove this function. Signed-off-by: Sebastian Ott Reviewed-by: Stefan Haberland Signed-off-by: Martin Schwidefsky

s390/dasd: fix IO error for newly defined devices

2018-04-23T05:57:16Z

When a new CKD storage volume is defined at the storage server, Linux may be relying on outdated information about that volume, which leads to the following errors: 1. Command Reject Errors for minidisk on z/VM: dasd-eckd.b3193d: 0.0.XXXX: An error occurred in the DASD device driver, reason=09 dasd(eckd): I/O status report for device 0.0.XXXX: dasd(eckd): in req: 00000000XXXXXXXX CC:00 FC:04 AC:00 SC:17 DS:02 CS:00 RC:0 dasd(eckd): device 0.0.2046: Failing CCW: 00000000XXXXXXXX dasd(eckd): Sense(hex) 0- 7: 80 00 00 00 00 00 00 00 dasd(eckd): Sense(hex) 8-15: 00 00 00 00 00 00 00 00 dasd(eckd): Sense(hex) 16-23: 00 00 00 00 e1 00 0f 00 dasd(eckd): Sense(hex) 24-31: 00 00 40 e2 00 00 00 00 dasd(eckd): 24 Byte: 0 MSG 0, no MSGb to SYSOP 2. Equipment Check errors on LPAR or for dedicated devices on z/VM: dasd(eckd): I/O status report for device 0.0.XXXX: dasd(eckd): in req: 00000000XXXXXXXX CC:00 FC:04 AC:00 SC:17 DS:0E CS:40 fcxs:01 schxs:00 RC:0 dasd(eckd): device 0.0.9713: Failing TCW: 00000000XXXXXXXX dasd(eckd): Sense(hex) 0- 7: 10 00 00 00 13 58 4d 0f dasd(eckd): Sense(hex) 8-15: 67 00 00 00 00 00 00 04 dasd(eckd): Sense(hex) 16-23: e5 18 05 33 97 01 0f 0f dasd(eckd): Sense(hex) 24-31: 00 00 40 e2 00 04 58 0d dasd(eckd): 24 Byte: 0 MSG f, no MSGb to SYSOP Fix this problem by using the up-to-date information provided during online processing via the device specific SNEQ to detect the case of outdated LCU data. If there is a difference, perform a re-read of that data. Cc: stable@vger.kernel.org Reviewed-by: Jan Hoeppner Signed-off-by: Stefan Haberland Signed-off-by: Martin Schwidefsky

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02T10:10:55Z

Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart Reviewed-by: Philippe Ombredanne Reviewed-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

s390/dasd: remove unneeded code

2017-07-05T05:35:29Z

Fix these set but not used warnings: drivers/s390/block/dasd.c:3933:6: warning: variable 'rc' set but not used [-Wunused-but-set-variable] drivers/s390/block/dasd_alias.c:757:6: warning: variable 'rc' set but not used [-Wunused-but-set-variable] In addition to that remove the test if an unsigned is < 0: drivers/s390/block/dasd_devmap.c:153:11: warning: comparison of unsigned expression < 0 is always false [-Wtype-limits] Signed-off-by: Sebastian Ott Signed-off-by: Martin Schwidefsky

s390/dasd: reorder lcu and device lock

2016-03-17T12:18:25Z

Reorder lcu and device lock to get rid of the error-prone trylock mechanism. The locking order is lcu lock -> device lock. This protects against changes to the lcu device lists and enables us to iterate over the devices, take the cdev lock and make changes to the device structures. The complicated part is the summary unit check handler that gets an interrupt on one device of the lcu that leads to structural changes of the whole lcu itself. This work needs to be done even if devices on the lcu disappear. So a device independent worker is used. The old approach tried to update some lcu structures and set up the lcu worker in the interrupt context with the device lock held. But this forced the lock order "cdev lock -> lcu lock" that made it hard to have the lcu lock held and iterate over all devices and change them. The new approach is to schedule a device specific worker that gets out of the interrupt context and rid of the device lock for summary unit checks. This worker is able to take the lcu lock and schedule the lcu worker that updates all devices. The time between interrupt and worker execution is no problem because the devices in the lcu reject all I/O in this time with an appropriate error. The dasd driver can deal with this situation and re-drive the I/O later on. Signed-off-by: Stefan Haberland Signed-off-by: Martin Schwidefsky

s390/dasd: remove casts to dasd_*_private

2016-03-07T12:12:02Z

Convert dasd_device.private to be a void pointer to get rid of a lot of explicit casts. Signed-off-by: Sebastian Ott Reviewed-by: Stefan Haberland Acked-by: Heiko Carstens Signed-off-by: Martin Schwidefsky

s390/dasd: fix incorrect locking order for LCU device add/remove

2016-02-23T07:56:19Z

The correct lock order for LCU lock and cdev lock is to take the cdev lock first and afterwards the LCU lock. This is caused by the fact that LCU functions are called in an interrupt context with the cdev lock implicitly hold by CIO. To assure the right locking order but also be able to iterate over devices in a LCU introduce a trylock block that can be called with the device lock for one device hold and then takes the LCU lock and try to lock all devices accounted to this LCU. Afterwards all devices and the LCU itself are locked. Signed-off-by: Stefan Haberland Signed-off-by: Martin Schwidefsky

s390/dasd: fix refcount for PAV reassignment

2016-02-11T12:05:55Z

Add refcount to the DASD device when a summary unit check worker is scheduled. This prevents that the device is set offline with worker in place. Cc: stable@vger.kernel.org Signed-off-by: Stefan Haberland Signed-off-by: Martin Schwidefsky