<feed xmlns='http://www.w3.org/2005/Atom'>
<title>lwn.git/drivers/s390/block, branch docs-6.8</title>
<subtitle>Linux kernel documentation tree maintained by Jonathan Corbet</subtitle>
<id>http://mirrors.hust.edu.cn/git/lwn.git/atom?h=docs-6.8</id>
<link rel='self' href='http://mirrors.hust.edu.cn/git/lwn.git/atom?h=docs-6.8'/>
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<updated>2023-10-28T11:29:18+00:00</updated>
<entry>
<title>s390/dasd: Convert to bdev_open_by_path()</title>
<updated>2023-10-28T11:29:18+00:00</updated>
<author>
<name>Jan Kara</name>
<email>jack@suse.cz</email>
</author>
<published>2023-09-27T09:34:20+00:00</published>
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<id>urn:sha1:a8ab90ff47bf2a2c9b1353592e14e46f87551b82</id>
<content type='text'>
Convert dasd to use bdev_open_by_path() and pass the handle around.

CC: linux-s390@vger.kernel.org
CC: Christian Borntraeger &lt;borntraeger@linux.ibm.com&gt;
CC: Sven Schnelle &lt;svens@linux.ibm.com&gt;
Acked-by: Christoph Hellwig &lt;hch@lst.de&gt;
Acked-by: Christian Brauner &lt;brauner@kernel.org&gt;
Signed-off-by: Jan Kara &lt;jack@suse.cz&gt;
Link: https://lore.kernel.org/r/20230927093442.25915-14-jack@suse.cz
Signed-off-by: Christian Brauner &lt;brauner@kernel.org&gt;
</content>
</entry>
<entry>
<title>Merge tag 'block-6.6-2023-09-08' of git://git.kernel.dk/linux</title>
<updated>2023-09-09T04:39:54+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2023-09-09T04:39:54+00:00</published>
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<id>urn:sha1:7402e635edb9b430125017d2489974c9a10b069c</id>
<content type='text'>
Pull block fixes from Jens Axboe:

 - Fix null_blk polled IO timeout handling (Chengming)

 - Regression fix for swapped arguments in drbd bvec_set_page()
   (Christoph)

 - String length handling fix for s390 dasd (Heiko)

 - Fixes for blk-throttle accounting (Yu)

 - Fix page pinning issue for same page segments (Christoph)

 - Remove redundant file_remove_privs() call (Christoph)

 - Fix a regression in partition handling for devices not supporting
   partitions (Li)

* tag 'block-6.6-2023-09-08' of git://git.kernel.dk/linux:
  drbd: swap bvec_set_page len and offset
  block: fix pin count management when merging same-page segments
  null_blk: fix poll request timeout handling
  s390/dasd: fix string length handling
  block: don't add or resize partition on the disk with GENHD_FL_NO_PART
  block: remove the call to file_remove_privs in blkdev_write_iter
  blk-throttle: consider 'carryover_ios/bytes' in throtl_trim_slice()
  blk-throttle: use calculate_io/bytes_allowed() for throtl_trim_slice()
  blk-throttle: fix wrong comparation while 'carryover_ios/bytes' is negative
  blk-throttle: print signed value 'carryover_bytes/ios' for user
</content>
</entry>
<entry>
<title>s390/dasd: fix string length handling</title>
<updated>2023-09-01T13:47:43+00:00</updated>
<author>
<name>Heiko Carstens</name>
<email>hca@linux.ibm.com</email>
</author>
<published>2023-08-28T15:31:42+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=f7cf22424665043787a96a66a048ff6b2cfd473c'/>
<id>urn:sha1:f7cf22424665043787a96a66a048ff6b2cfd473c</id>
<content type='text'>
Building dasd_eckd.o with latest clang reveals this bug:

    CC      drivers/s390/block/dasd_eckd.o
      drivers/s390/block/dasd_eckd.c:1082:3: warning: 'snprintf' will always be truncated;
      specified size is 1, but format string expands to at least 11 [-Wfortify-source]
       1082 |                 snprintf(print_uid, sizeof(*print_uid),
            |                 ^
      drivers/s390/block/dasd_eckd.c:1087:3: warning: 'snprintf' will always be truncated;
      specified size is 1, but format string expands to at least 10 [-Wfortify-source]
       1087 |                 snprintf(print_uid, sizeof(*print_uid),
            |                 ^

Fix this by moving and using the existing UID_STRLEN for the arrays
that are being written to. Also rename UID_STRLEN to DASD_UID_STRLEN
to clarify its scope.

Fixes: 23596961b437 ("s390/dasd: split up dasd_eckd_read_conf")
Reviewed-by: Peter Oberparleiter &lt;oberpar@linux.ibm.com&gt;
Signed-off-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Tested-by: Nick Desaulniers &lt;ndesaulniers@google.com&gt; # build
Reported-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Closes: https://github.com/ClangBuiltLinux/linux/issues/1923
Reviewed-by: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
Link: https://lore.kernel.org/r/20230828153142.2843753-2-hca@linux.ibm.com
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</content>
</entry>
<entry>
<title>s390/dcssblk: fix lockdep warning</title>
<updated>2023-08-30T09:03:27+00:00</updated>
<author>
<name>Gerald Schaefer</name>
<email>gerald.schaefer@linux.ibm.com</email>
</author>
<published>2023-08-22T15:19:32+00:00</published>
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<id>urn:sha1:789dd8cb1eb1503c8167bf2ffc88f74a70245044</id>
<content type='text'>
dcssblk_remove_store() holds the dcssblk_devices_sem semaphore while
calling del_gendisk(dev_info-&gt;gd), which in turn tries to acquire
disk-&gt;open_mutex. Then there is dcssblk_release(), which is called
with disk-&gt;open_mutex held, and tries to acquire dcssblk_devices_sem.

Lockdep reports this as possible circular locking dependency (CPU0 =
dcssblk_remove_store, CPU1 = dcssblk_release):

[   44.948865]  Possible unsafe locking scenario:

[   44.948866]        CPU0                    CPU1
[   44.948867]        ----                    ----
[   44.948868]   lock(&amp;dcssblk_devices_sem);
[   44.948870]                                lock(&amp;disk-&gt;open_mutex);
[   44.948872]                                lock(&amp;dcssblk_devices_sem);
[   44.948874]   lock(&amp;disk-&gt;open_mutex);
[   44.948876]
                *** DEADLOCK ***

In practice, this deadlock should not happen, since dcssblk_remove_store()
checks for dev_info-&gt;use_count != 0 after acquiring dcssblk_devices_sem,
and breaks out before calling del_gendisk(). dev_info-&gt;use_count will be
decremented in dcssblk_release(), protected by dcssblk_devices_sem.

Still there is no need for dcssblk_remove_store() to hold the
dcssblk_devices_sem until after calling del_gendisk(), as this only
protects dcssblk internal data. So fix the lockdep warning by releasing
dcssblk_devices_sem earlier. Also move the segment_unload() loop up,
similar to dcssblk_shared_store() error path, no need to do that after
calling del_gendisk().

Also change dcssblk_shared_store() error path, where dcssblk_devices_sem
was also released only after calling del_gendisk(), and a similar lockdep
warning could be triggered (but also deadlock prevented by check for
dev_info-&gt;use_count).

Acked-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Signed-off-by: Gerald Schaefer &lt;gerald.schaefer@linux.ibm.com&gt;
Signed-off-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
</content>
</entry>
<entry>
<title>Merge tag 's390-6.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux</title>
<updated>2023-08-29T00:22:39+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2023-08-29T00:22:39+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=e5b7ca09e9aa4d483ab84c5f2ba88f0cc7c66540'/>
<id>urn:sha1:e5b7ca09e9aa4d483ab84c5f2ba88f0cc7c66540</id>
<content type='text'>
Pull s390 updates from Heiko Carstens:

 - Add vfio-ap support to pass-through crypto devices to secure
   execution guests

 - Add API ordinal 6 support to zcrypt_ep11misc device drive, which is
   required to handle key generate and key derive (e.g. secure key to
   protected key) correctly

 - Add missing secure/has_secure sysfs files for the case where it is
   not possible to figure where a system has been booted from. Existing
   user space relies on that these files are always present

 - Fix DCSS block device driver list corruption, caused by incorrect
   error handling

 - Convert virt_to_pfn() and pfn_to_virt() from defines to static inline
   functions to enforce type checking

 - Cleanups, improvements, and minor fixes to the kernel mapping setup

 - Fix various virtual vs physical address confusions

 - Move pfault code to separate file, since it has nothing to do with
   regular fault handling

 - Move s390 documentation to Documentation/arch/ like it has been done
   for other architectures already

 - Add HAVE_FUNCTION_GRAPH_RETVAL support

 - Factor out the s390_hypfs filesystem and add a new config option for
   it. The filesystem is deprecated and as soon as all users are gone it
   can be removed some time in the not so near future

 - Remove support for old CEX2 and CEX3 crypto cards from zcrypt device
   driver

 - Add support for user-defined certificates: receive user-defined
   certificates with a diagnose call and provide them via 'cert_store'
   keyring to user space

 - Couple of other small fixes and improvements all over the place

* tag 's390-6.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (66 commits)
  s390/pci: use builtin_misc_device macro to simplify the code
  s390/vfio-ap: make sure nib is shared
  KVM: s390: export kvm_s390_pv*_is_protected functions
  s390/uv: export uv_pin_shared for direct usage
  s390/vfio-ap: check for TAPQ response codes 0x35 and 0x36
  s390/vfio-ap: handle queue state change in progress on reset
  s390/vfio-ap: use work struct to verify queue reset
  s390/vfio-ap: store entire AP queue status word with the queue object
  s390/vfio-ap: remove upper limit on wait for queue reset to complete
  s390/vfio-ap: allow deconfigured queue to be passed through to a guest
  s390/vfio-ap: wait for response code 05 to clear on queue reset
  s390/vfio-ap: clean up irq resources if possible
  s390/vfio-ap: no need to check the 'E' and 'I' bits in APQSW after TAPQ
  s390/ipl: refactor deprecated strncpy
  s390/ipl: fix virtual vs physical address confusion
  s390/zcrypt_ep11misc: support API ordinal 6 with empty pin-blob
  s390/paes: fix PKEY_TYPE_EP11_AES handling for secure keyblobs
  s390/pkey: fix PKEY_TYPE_EP11_AES handling for sysfs attributes
  s390/pkey: fix PKEY_TYPE_EP11_AES handling in PKEY_VERIFYKEY2 IOCTL
  s390/pkey: fix PKEY_TYPE_EP11_AES handling in PKEY_KBLOB2PROTK[23]
  ...
</content>
</entry>
<entry>
<title>Merge tag 'v6.6-vfs.super' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs</title>
<updated>2023-08-28T18:04:18+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2023-08-28T18:04:18+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=511fb5bafed197ff76d9adf5448de67f1d0558ae'/>
<id>urn:sha1:511fb5bafed197ff76d9adf5448de67f1d0558ae</id>
<content type='text'>
Pull superblock updates from Christian Brauner:
 "This contains the super rework that was ready for this cycle. The
  first part changes the order of how we open block devices and allocate
  superblocks, contains various cleanups, simplifications, and a new
  mechanism to wait on superblock state changes.

  This unblocks work to ultimately limit the number of writers to a
  block device. Jan has already scheduled follow-up work that will be
  ready for v6.7 and allows us to restrict the number of writers to a
  given block device. That series builds on this work right here.

  The second part contains filesystem freezing updates.

  Overview:

  The generic superblock changes are rougly organized as follows
  (ignoring additional minor cleanups):

   (1) Removal of the bd_super member from struct block_device.

       This was a very odd back pointer to struct super_block with
       unclear rules. For all relevant places we have other means to get
       the same information so just get rid of this.

   (2) Simplify rules for superblock cleanup.

       Roughly, everything that is allocated during fs_context
       initialization and that's stored in fs_context-&gt;s_fs_info needs
       to be cleaned up by the fs_context-&gt;free() implementation before
       the superblock allocation function has been called successfully.

       After sget_fc() returned fs_context-&gt;s_fs_info has been
       transferred to sb-&gt;s_fs_info at which point sb-&gt;kill_sb() if
       fully responsible for cleanup. Adhering to these rules means that
       cleanup of sb-&gt;s_fs_info in fill_super() is to be avoided as it's
       brittle and inconsistent.

       Cleanup shouldn't be duplicated between sb-&gt;put_super() as
       sb-&gt;put_super() is only called if sb-&gt;s_root has been set aka
       when the filesystem has been successfully born (SB_BORN). That
       complexity should be avoided.

       This also means that block devices are to be closed in
       sb-&gt;kill_sb() instead of sb-&gt;put_super(). More details in the
       lower section.

   (3) Make it possible to lookup or create a superblock before opening
       block devices

       There's a subtle dependency on (2) as some filesystems did rely
       on fill_super() to be called in order to correctly clean up
       sb-&gt;s_fs_info. All these filesystems have been fixed.

   (4) Switch most filesystem to follow the same logic as the generic
       mount code now does as outlined in (3).

   (5) Use the superblock as the holder of the block device. We can now
       easily go back from block device to owning superblock.

   (6) Export and extend the generic fs_holder_ops and use them as
       holder ops everywhere and remove the filesystem specific holder
       ops.

   (7) Call from the block layer up into the filesystem layer when the
       block device is removed, allowing to shut down the filesystem
       without risk of deadlocks.

   (8) Get rid of get_super().

       We can now easily go back from the block device to owning
       superblock and can call up from the block layer into the
       filesystem layer when the device is removed. So no need to wade
       through all registered superblock to find the owning superblock
       anymore"

Link: https://lore.kernel.org/lkml/20230824-prall-intakt-95dbffdee4a0@brauner/

* tag 'v6.6-vfs.super' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (47 commits)
  super: use higher-level helper for {freeze,thaw}
  super: wait until we passed kill super
  super: wait for nascent superblocks
  super: make locking naming consistent
  super: use locking helpers
  fs: simplify invalidate_inodes
  fs: remove get_super
  block: call into the file system for ioctl BLKFLSBUF
  block: call into the file system for bdev_mark_dead
  block: consolidate __invalidate_device and fsync_bdev
  block: drop the "busy inodes on changed media" log message
  dasd: also call __invalidate_device when setting the device offline
  amiflop: don't call fsync_bdev in FDFMTBEG
  floppy: call disk_force_media_change when changing the format
  block: simplify the disk_force_media_change interface
  nbd: call blk_mark_disk_dead in nbd_clear_sock_ioctl
  xfs use fs_holder_ops for the log and RT devices
  xfs: drop s_umount over opening the log and RT devices
  ext4: use fs_holder_ops for the log device
  ext4: drop s_umount over opening the log device
  ...
</content>
</entry>
<entry>
<title>block: consolidate __invalidate_device and fsync_bdev</title>
<updated>2023-08-21T12:35:31+00:00</updated>
<author>
<name>Christoph Hellwig</name>
<email>hch@lst.de</email>
</author>
<published>2023-08-11T10:08:24+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=560e20e4bf6484a0c12f9f3c7a1aa55056948e1e'/>
<id>urn:sha1:560e20e4bf6484a0c12f9f3c7a1aa55056948e1e</id>
<content type='text'>
We currently have two interfaces that take a block_devices and the find
a mounted file systems to flush or invaldidate data on it.  Both are a
bit problematic because they only work for the "main" block devices
that is used as s_dev for the super_block, and because they don't call
into the file system at all.

Merge the two into a new bdev_mark_dead helper that does both the
syncing and invalidation and which is properly documented.  This is
in preparation of merging the functionality into the -&gt;mark_dead
holder operation so that it will work on additional block devices
used by a file systems and give us a single entry point for invalidation
of dead devices or media.

Note that a single standalone fsync_bdev call for an obscure ioctl
remains for now, but that one will also be deal with in a bit.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Josef Bacik &lt;josef@toxicpanda.com&gt;
Message-Id: &lt;20230811100828.1897174-14-hch@lst.de&gt;
Signed-off-by: Christian Brauner &lt;brauner@kernel.org&gt;
</content>
</entry>
<entry>
<title>dasd: also call __invalidate_device when setting the device offline</title>
<updated>2023-08-21T12:35:31+00:00</updated>
<author>
<name>Christoph Hellwig</name>
<email>hch@lst.de</email>
</author>
<published>2023-08-11T10:08:22+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=2527fd38772fea30c1d1cbf94839a0bbf4122133'/>
<id>urn:sha1:2527fd38772fea30c1d1cbf94839a0bbf4122133</id>
<content type='text'>
Don't just write out the data, but also invalidate all caches when setting
the device offline.  Stop canceling the offlining when writeback fails
as there is no way to recover from that anyway.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Josef Bacik &lt;josef@toxicpanda.com&gt;
Message-Id: &lt;20230811100828.1897174-12-hch@lst.de&gt;
Signed-off-by: Christian Brauner &lt;brauner@kernel.org&gt;
</content>
</entry>
<entry>
<title>s390/dcssblk: fix kernel crash with list_add corruption</title>
<updated>2023-08-16T13:13:03+00:00</updated>
<author>
<name>Gerald Schaefer</name>
<email>gerald.schaefer@linux.ibm.com</email>
</author>
<published>2023-08-10T08:22:36+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=c8f40a0bccefd613748d080147469a4652d6e74c'/>
<id>urn:sha1:c8f40a0bccefd613748d080147469a4652d6e74c</id>
<content type='text'>
Commit fb08a1908cb1 ("dax: simplify the dax_device &lt;-&gt; gendisk
association") introduced new logic for gendisk association, requiring
drivers to explicitly call dax_add_host() and dax_remove_host().

For dcssblk driver, some dax_remove_host() calls were missing, e.g. in
device remove path. The commit also broke error handling for out_dax case
in device add path, resulting in an extra put_device() w/o the previous
get_device() in that case.

This lead to stale xarray entries after device add / remove cycles. In the
case when a previously used struct gendisk pointer (xarray index) would be
used again, because blk_alloc_disk() happened to return such a pointer, the
xa_insert() in dax_add_host() would fail and go to out_dax, doing the extra
put_device() in the error path. In combination with an already flawed error
handling in dcssblk (device_register() cleanup), which needs to be
addressed in a separate patch, this resulted in a missing device_del() /
klist_del(), and eventually in the kernel crash with list_add corruption on
a subsequent device_add() / klist_add().

Fix this by adding the missing dax_remove_host() calls, and also move the
put_device() in the error path to restore the previous logic.

Fixes: fb08a1908cb1 ("dax: simplify the dax_device &lt;-&gt; gendisk association")
Cc: &lt;stable@vger.kernel.org&gt; # 5.17+
Acked-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Signed-off-by: Gerald Schaefer &lt;gerald.schaefer@linux.ibm.com&gt;
Signed-off-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
</content>
</entry>
<entry>
<title>s390/mm: make virt_to_pfn() a static inline</title>
<updated>2023-08-16T13:13:03+00:00</updated>
<author>
<name>Linus Walleij</name>
<email>linus.walleij@linaro.org</email>
</author>
<published>2023-08-12T15:12:54+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=2d1494fb31405df0dfb6006fdb2b24e7880258cd'/>
<id>urn:sha1:2d1494fb31405df0dfb6006fdb2b24e7880258cd</id>
<content type='text'>
Making virt_to_pfn() a static inline taking a strongly typed
(const void *) makes the contract of a passing a pointer of that
type to the function explicit and exposes any misuse of the
macro virt_to_pfn() acting polymorphic and accepting many types
such as (void *), (unitptr_t) or (unsigned long) as arguments
without warnings.

For symmetry do the same with pfn_to_virt() reflecting the
current layout in asm-generic/page.h.

Doing this reveals a number of offenders in the arch code and
the S390-specific drivers, so just bite the bullet and fix up
all of those as well.

Signed-off-by: Linus Walleij &lt;linus.walleij@linaro.org&gt;
Reviewed-by: Alexander Gordeev &lt;agordeev@linux.ibm.com&gt;
Link: https://lore.kernel.org/r/20230812-virt-to-phys-s390-v2-1-6c40f31fe36f@linaro.org
Signed-off-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
</content>
</entry>
</feed>
