kernel/linux.git/drivers/s390/block, branch v5.4.50

s390/dasd: fix data corruption for thin provisioned devices

2020-03-18T06:17:52+00:00

commit 5e6bdd37c5526ef01326df5dabb93011ee89237e upstream. Devices are formatted in multiple of tracks. For an Extent Space Efficient (ESE) volume we get errors when accessing unformatted tracks. In this case the driver either formats the track on the flight for write requests or returns zero data for read requests. In case a request spans multiple tracks, the indication of an unformatted track presented for the first track is incorrectly applied to all tracks covered by the request. As a result, tracks containing data will be handled as empty, resulting in zero data being returned on read, or overwriting existing data with zero on write. Fix by determining the track that gets the NRF error. For write requests only format the track that is surely not formatted. For Read requests all tracks before have returned valid data and should not be touched. All tracks after the unformatted track might be formatted or not. Those are returned to the blocklayer to build a new request. When using alias devices there is a chance that multiple write requests trigger a format of the same track which might lead to data loss. Ensure that a track is formatted only once by maintaining a list of currently processed tracks. Fixes: 5e2b17e712cf ("s390/dasd: Add dynamic formatting support for ESE volumes") Cc: stable@vger.kernel.org # 5.3+ Signed-off-by: Stefan Haberland Reviewed-by: Jan Hoeppner Reviewed-by: Peter Oberparleiter Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

s390/dasd: fix memleak in path handling error case

2020-01-12T11:21:43+00:00

[ Upstream commit 00b39f698a4f1ee897227cace2e3937fc4412270 ] If for whatever reason the dasd_eckd_check_characteristics() function exits after at least some paths have their configuration data allocated those data is never freed again. In the error case the device->private pointer is set to NULL and dasd_eckd_uncheck_device() will exit without freeing the path data because of this NULL pointer. Fix by calling dasd_eckd_clear_conf_data() for error cases. Also use dasd_eckd_clear_conf_data() in dasd_eckd_uncheck_device() to avoid code duplication. Reported-by: Qian Cai Reviewed-by: Jan Hoeppner Signed-off-by: Stefan Haberland Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin

s390/dasd/cio: Interpret ccw_device_get_mdc return value correctly

2020-01-12T11:21:43+00:00

[ Upstream commit dd4b3c83b9efac10d48a94c61372119fc555a077 ] The max data count (mdc) is an unsigned 16-bit integer value as per AR documentation and is received via ccw_device_get_mdc() for a specific path mask from the CIO layer. The function itself also always returns a positive mdc value or 0 in case mdc isn't supported or couldn't be determined. Though, the comment for this function describes a negative return value to indicate failures. As a result, the DASD device driver interprets the return value of ccw_device_get_mdc() incorrectly. The error case is essentially a dead code path. To fix this behaviour, check explicitly for a return value of 0 and change the comment for ccw_device_get_mdc() accordingly. This fix merely enables the error code path in the DASD functions get_fcx_max_data() and verify_fcx_max_data(). The actual functionality stays the same and is still correct. Reviewed-by: Cornelia Huck Signed-off-by: Jan Höppner Acked-by: Peter Oberparleiter Reviewed-by: Stefan Haberland Signed-off-by: Stefan Haberland Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin

Revert "s390/dasd: Add discard support for ESE volumes"

2019-10-01T15:53:36+00:00

This reverts commit 7e64db1597fe114b83fe17d0ba96c6aa5fca419a. The thin provisioning feature introduces an IOCTL and the discard support to allow userspace tools and filesystems to release unused and previously allocated space respectively. During some internal performance improvements and further tests, the release of allocated space revealed some issues that may lead to data corruption in some configurations when filesystems are mounted with discard support enabled. While we're working on a fix and trying to clarify the situation, this commit reverts the discard support for ESE volumes to prevent potential data corruption. Cc: # 5.3 Signed-off-by: Stefan Haberland Signed-off-by: Jens Axboe

s390/dasd: Fix error handling during online processing

2019-10-01T15:53:36+00:00

It is possible that the CCW commands for reading volume and extent pool information are not supported, either by the storage server (for dedicated DASDs) or by z/VM (for virtual devices, such as MDISKs). As a command reject will occur in such a case, the current error handling leads to a failing online processing and thus the DASD can't be used at all. Since the data being read is not essential for an fully operational DASD, the error handling can be removed. Information about the failing command is sent to the s390dbf debug feature. Fixes: c729696bcf8b ("s390/dasd: Recognise data for ESE volumes") Cc: # 5.3 Reported-by: Frank Heimes Signed-off-by: Jan Höppner Signed-off-by: Stefan Haberland Signed-off-by: Jens Axboe

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

2019-08-02T02:46:14+00:00

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

Merge tag 'libnvdimm-for-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

2019-07-18T17:52:08+00:00

Pull libnvdimm updates from Dan Williams: "Primarily just the virtio_pmem driver: - virtio_pmem The new virtio_pmem facility introduces a paravirtualized persistent memory device that allows a guest VM to use DAX mechanisms to access a host-file with host-page-cache. It arranges for MAP_SYNC to be disabled and instead triggers a host fsync() when a 'write-cache flush' command is sent to the virtual disk device. - Miscellaneous small fixups" * tag 'libnvdimm-for-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: virtio_pmem: fix sparse warning xfs: disable map_sync for async flush ext4: disable map_sync for async flush dax: check synchronous mapping is supported dm: enable synchronous dax libnvdimm: add dax_dev sync flag virtio-pmem: Add virtio pmem driver libnvdimm: nd_region flush callback support libnvdimm, namespace: Drop uuid_t implementation detail

s390/dasd: Handle out-of-space constraint

2019-07-11T18:39:54+00:00

The storage server issues three different types of out-of-space messages whenever the Extent Pool or Extent Repository space runs short. When a configured warning watermark is reached, the physical space is completeley exhausted, or the capacity constraints have been relieved, a message is received. A log entry for the sysadmin to react to is generated in any case. In case the physical space is completely exhausted, sense data that reads "no space left on device" is received. In this case, currently running I/O will be blocked until space has either been released or added to the extent pool, and a relieve message was received via an attention interrupt. Signed-off-by: Jan Höppner Reviewed-by: Stefan Haberland Signed-off-by: Vasily Gorbik

s390/dasd: Add discard support for ESE volumes

2019-07-11T18:39:54+00:00

ESE (Extent Space Efficient) volumes are thin-provisioned and therefore space is only occupied with real data. In order to make previously used space available for re-allocation again, discard support is enabled for ESE volumes allowing the DASD driver to release said space. Signed-off-by: Jan Höppner Reviewed-by: Stefan Haberland Signed-off-by: Vasily Gorbik

s390/dasd: Use ALIGN_DOWN macro

2019-07-11T18:39:54+00:00

There is now an ALIGN_DOWN macro available. Let's rather use kernel provided macros that do the things we want. Signed-off-by: Jan Höppner Reviewed-by: Stefan Haberland Signed-off-by: Vasily Gorbik