<feed xmlns='http://www.w3.org/2005/Atom'>
<title>user/sven/linux.git/drivers/md/persistent-data, branch v5.8.1</title>
<subtitle>Linux Kernel
</subtitle>
<id>https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v5.8.1</id>
<link rel='self' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v5.8.1'/>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/'/>
<updated>2020-06-13T16:57:21Z</updated>
<entry>
<title>treewide: replace '---help---' in Kconfig files with 'help'</title>
<updated>2020-06-13T16:57:21Z</updated>
<author>
<name>Masahiro Yamada</name>
<email>masahiroy@kernel.org</email>
</author>
<published>2020-06-13T16:50:22Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=a7f7f6248d9740d710fd6bd190293fe5e16410ac'/>
<id>urn:sha1:a7f7f6248d9740d710fd6bd190293fe5e16410ac</id>
<content type='text'>
Since commit 84af7a6194e4 ("checkpatch: kconfig: prefer 'help' over
'---help---'"), the number of '---help---' has been gradually
decreasing, but there are still more than 2400 instances.

This commit finishes the conversion. While I touched the lines,
I also fixed the indentation.

There are a variety of indentation styles found.

  a) 4 spaces + '---help---'
  b) 7 spaces + '---help---'
  c) 8 spaces + '---help---'
  d) 1 space + 1 tab + '---help---'
  e) 1 tab + '---help---'    (correct indentation)
  f) 1 tab + 1 space + '---help---'
  g) 1 tab + 2 spaces + '---help---'

In order to convert all of them to 1 tab + 'help', I ran the
following commend:

  $ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/'

Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
</content>
</entry>
<entry>
<title>dm: replace zero-length array with flexible-array</title>
<updated>2020-05-20T21:09:44Z</updated>
<author>
<name>Gustavo A. R. Silva</name>
<email>gustavoars@kernel.org</email>
</author>
<published>2020-05-07T18:51:58Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=b18ae8dd9d7685233d7be472c043c545f18d015a'/>
<id>urn:sha1:b18ae8dd9d7685233d7be472c043c545f18d015a</id>
<content type='text'>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
        int stuff;
        struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by
this change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

sizeof(flexible-array-member) triggers a warning because flexible array
members have incomplete type[1]. There are some instances of code in
which the sizeof operator is being incorrectly/erroneously applied to
zero-length arrays and the result is zero. Such instances may be hiding
some bugs. So, this work (flexible-array member conversions) will also
help to get completely rid of those sorts of issues.

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva &lt;gustavoars@kernel.org&gt;
Signed-off-by: Mike Snitzer &lt;snitzer@redhat.com&gt;
</content>
</entry>
<entry>
<title>dm persistent data: switch exit_ro_spine to return void</title>
<updated>2020-05-15T14:29:35Z</updated>
<author>
<name>Zhiqiang Liu</name>
<email>liuzhiqiang26@huawei.com</email>
</author>
<published>2020-04-15T11:57:31Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=9431cf6efc3659eaa1cdd591e02a09045bc9983f'/>
<id>urn:sha1:9431cf6efc3659eaa1cdd591e02a09045bc9983f</id>
<content type='text'>
In commit 4c7da06f5a78 ("dm persistent data: eliminate unnecessary
return values"), r value in exit_ro_spine will not change, so
exit_ro_spine doesn't need a return value.

Signed-off-by: Zhiqiang Liu &lt;liuzhiqiang26@huawei.com&gt;
Signed-off-by: Mike Snitzer &lt;snitzer@redhat.com&gt;
</content>
</entry>
<entry>
<title>dm space map common: fix to ensure new block isn't already in use</title>
<updated>2020-01-15T01:15:53Z</updated>
<author>
<name>Joe Thornber</name>
<email>ejt@redhat.com</email>
</author>
<published>2020-01-07T11:58:42Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=4feaef830de7ffdd8352e1fe14ad3bf13c9688f8'/>
<id>urn:sha1:4feaef830de7ffdd8352e1fe14ad3bf13c9688f8</id>
<content type='text'>
The space-maps track the reference counts for disk blocks allocated by
both the thin-provisioning and cache targets.  There are variants for
tracking metadata blocks and data blocks.

Transactionality is implemented by never touching blocks from the
previous transaction, so we can rollback in the event of a crash.

When allocating a new block we need to ensure the block is free (has
reference count of 0) in both the current and previous transaction.
Prior to this fix we were doing this by searching for a free block in
the previous transaction, and relying on a 'begin' counter to track
where the last allocation in the current transaction was.  This
'begin' field was not being updated in all code paths (eg, increment
of a data block reference count due to breaking sharing of a neighbour
block in the same btree leaf).

This fix keeps the 'begin' field, but now it's just a hint to speed up
the search.  Instead the current transaction is searched for a free
block, and then the old transaction is double checked to ensure it's
free.  Much simpler.

This fixes reports of sm_disk_new_block()'s BUG_ON() triggering when
DM thin-provisioning's snapshots are heavily used.

Reported-by: Eric Wheeler &lt;dm-devel@lists.ewheeler.net&gt;
Cc: stable@vger.kernel.org
Signed-off-by: Joe Thornber &lt;ejt@redhat.com&gt;
Signed-off-by: Mike Snitzer &lt;snitzer@redhat.com&gt;
</content>
</entry>
<entry>
<title>dm btree: increase rebalance threshold in __rebalance2()</title>
<updated>2019-12-05T20:27:52Z</updated>
<author>
<name>Hou Tao</name>
<email>houtao1@huawei.com</email>
</author>
<published>2019-12-03T11:42:58Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=474e559567fa631dea8fb8407ab1b6090c903755'/>
<id>urn:sha1:474e559567fa631dea8fb8407ab1b6090c903755</id>
<content type='text'>
We got the following warnings from thin_check during thin-pool setup:

  $ thin_check /dev/vdb
  examining superblock
  examining devices tree
    missing devices: [1, 84]
      too few entries in btree_node: 41, expected at least 42 (block 138, max_entries = 126)
  examining mapping tree

The phenomenon is the number of entries in one node of details_info tree is
less than (max_entries / 3). And it can be easily reproduced by the following
procedures:

  $ new a thin pool
  $ presume the max entries of details_info tree is 126
  $ new 127 thin devices (e.g. 1~127) to make the root node being full
    and then split
  $ remove the first 43 (e.g. 1~43) thin devices to make the children
    reblance repeatedly
  $ stop the thin pool
  $ thin_check

The root cause is that the B-tree removal procedure in __rebalance2()
doesn't guarantee the invariance: the minimal number of entries in
non-root node should be &gt;= (max_entries / 3).

Simply fix the problem by increasing the rebalance threshold to
make sure the number of entries in each child will be greater
than or equal to (max_entries / 3 + 1), so no matter which
child is used for removal, the number will still be valid.

Cc: stable@vger.kernel.org
Signed-off-by: Hou Tao &lt;houtao1@huawei.com&gt;
Acked-by: Joe Thornber &lt;ejt@redhat.com&gt;
Signed-off-by: Mike Snitzer &lt;snitzer@redhat.com&gt;
</content>
</entry>
<entry>
<title>dm space map common: remove check for impossible sm_find_free() return value</title>
<updated>2019-08-26T19:39:53Z</updated>
<author>
<name>ZhangXiaoxu</name>
<email>zhangxiaoxu5@huawei.com</email>
</author>
<published>2019-06-09T07:52:00Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=c1499a044d7c2bbd9ea3d9c17e17f16595ae6d69'/>
<id>urn:sha1:c1499a044d7c2bbd9ea3d9c17e17f16595ae6d69</id>
<content type='text'>
The function sm_find_free() just returns -ENOSPC and 0.
So remove lone caller's check for some other error.

Signed-off-by: ZhangXiaoxu &lt;zhangxiaoxu5@huawei.com&gt;
Signed-off-by: Mike Snitzer &lt;snitzer@redhat.com&gt;
</content>
</entry>
<entry>
<title>dm space map metadata: fix missing store of apply_bops() return value</title>
<updated>2019-08-22T20:11:24Z</updated>
<author>
<name>ZhangXiaoxu</name>
<email>zhangxiaoxu5@huawei.com</email>
</author>
<published>2019-08-19T03:31:21Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=ae148243d3f0816b37477106c05a2ec7d5f32614'/>
<id>urn:sha1:ae148243d3f0816b37477106c05a2ec7d5f32614</id>
<content type='text'>
In commit 6096d91af0b6 ("dm space map metadata: fix occasional leak
of a metadata block on resize"), we refactor the commit logic to a new
function 'apply_bops'.  But when that logic was replaced in out() the
return value was not stored.  This may lead out() returning a wrong
value to the caller.

Fixes: 6096d91af0b6 ("dm space map metadata: fix occasional leak of a metadata block on resize")
Cc: stable@vger.kernel.org
Signed-off-by: ZhangXiaoxu &lt;zhangxiaoxu5@huawei.com&gt;
Signed-off-by: Mike Snitzer &lt;snitzer@redhat.com&gt;
</content>
</entry>
<entry>
<title>dm btree: fix order of block initialization in btree_split_beneath</title>
<updated>2019-08-22T20:11:23Z</updated>
<author>
<name>ZhangXiaoxu</name>
<email>zhangxiaoxu5@huawei.com</email>
</author>
<published>2019-08-17T05:32:40Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=e4f9d6013820d1eba1432d51dd1c5795759aa77f'/>
<id>urn:sha1:e4f9d6013820d1eba1432d51dd1c5795759aa77f</id>
<content type='text'>
When btree_split_beneath() splits a node to two new children, it will
allocate two blocks: left and right.  If right block's allocation
failed, the left block will be unlocked and marked dirty.  If this
happened, the left block'ss content is zero, because it wasn't
initialized with the btree struct before the attempot to allocate the
right block.  Upon return, when flushing the left block to disk, the
validator will fail when check this block.  Then a BUG_ON is raised.

Fix this by completely initializing the left block before allocating and
initializing the right block.

Fixes: 4dcb8b57df359 ("dm btree: fix leak of bufio-backed block in btree_split_beneath error path")
Cc: stable@vger.kernel.org
Signed-off-by: ZhangXiaoxu &lt;zhangxiaoxu5@huawei.com&gt;
Signed-off-by: Mike Snitzer &lt;snitzer@redhat.com&gt;
</content>
</entry>
<entry>
<title>treewide: Add SPDX license identifier - Makefile/Kconfig</title>
<updated>2019-05-21T08:50:46Z</updated>
<author>
<name>Thomas Gleixner</name>
<email>tglx@linutronix.de</email>
</author>
<published>2019-05-19T12:07:45Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=ec8f24b7faaf3d4799a7c3f4c1b87f6b02778ad1'/>
<id>urn:sha1:ec8f24b7faaf3d4799a7c3f4c1b87f6b02778ad1</id>
<content type='text'>
Add SPDX license identifiers to all Make/Kconfig files which:

 - Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>Merge tag 'for-5.2/dm-changes-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm</title>
<updated>2019-05-16T22:55:48Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2019-05-16T22:55:48Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=311f71281ff4b24f86a39c60c959f485c68a6d36'/>
<id>urn:sha1:311f71281ff4b24f86a39c60c959f485c68a6d36</id>
<content type='text'>
Pull device mapper updates from Mike Snitzer:

 - Improve DM snapshot target's scalability by using finer grained
   locking. Requires some list_bl interface improvements.

 - Add ability for DM integrity to use a bitmap mode, that tracks
   regions where data and metadata are out of sync, instead of using a
   journal.

 - Improve DM thin provisioning target to not write metadata changes to
   disk if the thin-pool and associated thin devices are merely
   activated but not used. This avoids metadata corruption due to
   concurrent activation of thin devices across different OS instances
   (e.g. split brain scenarios, which ultimately would be avoided if
   proper device filters were used -- but not having proper filtering
   has proven a very common configuration mistake)

 - Fix missing call to path selector type-&gt;end_io in DM multipath. This
   fixes reported performance problems due to inaccurate path selector
   IO accounting causing an imbalance of IO (e.g. avoiding issuing IO to
   particular path due to it seemingly being heavily used).

 - Fix bug in DM cache metadata's loading of its discard bitset that
   could lead to all cache blocks being discarded if the very first
   cache block was discarded (thankfully in practice the first cache
   block is generally in use; be it FS superblock, partition table, disk
   label, etc).

 - Add testing-only DM dust target which simulates a device that has
   failing sectors and/or read failures.

 - Fix a DM init error path reference count hang that caused boot hangs
   if user supplied malformed input on kernel commandline.

 - Fix a couple issues with DM crypt target's logging being overly
   verbose or lacking context.

 - Various other small fixes to DM init, DM multipath, DM zoned, and DM
   crypt.

* tag 'for-5.2/dm-changes-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (42 commits)
  dm: fix a couple brace coding style issues
  dm crypt: print device name in integrity error message
  dm crypt: move detailed message into debug level
  dm ioctl: fix hang in early create error condition
  dm integrity: whitespace, coding style and dead code cleanup
  dm integrity: implement synchronous mode for reboot handling
  dm integrity: handle machine reboot in bitmap mode
  dm integrity: add a bitmap mode
  dm integrity: introduce a function add_new_range_and_wait()
  dm integrity: allow large ranges to be described
  dm ingerity: pass size to dm_integrity_alloc_page_list()
  dm integrity: introduce rw_journal_sectors()
  dm integrity: update documentation
  dm integrity: don't report unused options
  dm integrity: don't check null pointer before kvfree and vfree
  dm integrity: correctly calculate the size of metadata area
  dm dust: Make dm_dust_init and dm_dust_exit static
  dm dust: remove redundant unsigned comparison to less than zero
  dm mpath: always free attached_handler_name in parse_path()
  dm init: fix max devices/targets checks
  ...
</content>
</entry>
</feed>
