Linux kernel for uConsole
  • C 97.1%
  • Assembly 1.8%
  • Shell 0.4%
  • Makefile 0.3%
  • Python 0.2%
Find a file
Joe Thornber 1fac9f574c dm space map common: fix to ensure new block isn't already in use
commit 4feaef830d upstream.

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 <dm-devel@lists.ewheeler.net>
Cc: stable@vger.kernel.org
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-11 04:34:03 -08:00
arch of: Add OF_DMA_DEFAULT_COHERENT & select it on powerpc 2020-02-11 04:34:03 -08:00
block block: fix 32 bit overflow in __blkdev_issue_discard() 2020-02-01 09:37:12 +00:00
certs export.h: remove VMLINUX_SYMBOL() and VMLINUX_SYMBOL_STR() 2018-08-22 23:21:44 +09:00
crypto crypto: api - Check spawn->alg under lock in crypto_drop_spawn 2020-02-11 04:34:01 -08:00
Documentation PM / devfreq: Add new name attribute for sysfs 2020-02-05 14:43:34 +00:00
drivers dm space map common: fix to ensure new block isn't already in use 2020-02-11 04:34:03 -08:00
firmware Fix built-in early-load Intel microcode alignment 2020-01-23 08:21:29 +01:00
fs f2fs: code cleanup for f2fs_statfs_project() 2020-02-11 04:34:03 -08:00
include media: v4l2-rect.h: fix v4l2_rect_map_inside() top/left adjustments 2020-02-11 04:33:57 -08:00
init fork: fix some -Wmissing-prototypes warnings 2019-12-05 09:21:04 +01:00
ipc ipc/msg.c: consolidate all xxxctl_down() functions 2020-02-11 04:33:55 -08:00
kernel alarmtimer: Unregister wakeup source when module get fails 2020-02-11 04:33:59 -08:00
lib lib/test_kasan.c: fix memory leak in kmalloc_oob_krealloc_more() 2020-02-11 04:33:57 -08:00
LICENSES LICENSES: Remove CC-BY-SA-4.0 license text 2018-10-18 11:28:50 +02:00
mm mm: move_pages: report the number of non-attempted pages 2020-02-11 04:33:56 -08:00
net rxrpc: Fix NULL pointer deref due to call->conn being cleared on disconnect 2020-02-11 04:33:54 -08:00
samples samples/bpf: Fix broken xdp_rxq_info due to map order assumptions 2020-01-27 14:51:22 +01:00
scripts scripts/find-unused-docs: Fix massive false positives 2020-02-11 04:34:01 -08:00
security tomoyo: Use atomic_t for statistics counter 2020-02-05 14:43:38 +00:00
sound ALSA: hda: Add Clevo W65_67SB the power_save blacklist 2020-02-11 04:33:57 -08:00
tools perf report: Fix no libunwind compiled warning break s390 issue 2020-02-05 14:43:54 +00:00
usr kbuild: clean compressed initramfs image 2019-10-07 18:57:16 +02:00
virt KVM: arm64: Only sign-extend MMIO up to register width 2020-02-11 04:33:58 -08:00
.clang-format clang-format: Set IndentWrappedFunctionNames false 2018-08-01 18:38:51 +02:00
.cocciconfig
.get_maintainer.ignore
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore Kbuild updates for v4.17 (2nd) 2018-04-15 17:21:30 -07:00
.mailmap libnvdimm-for-4.19_misc 2018-08-25 18:13:10 -07:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS 9p: remove Ron Minnich from MAINTAINERS 2018-08-17 16:20:26 -07:00
Kbuild Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
Kconfig kconfig: move the "Executable file formats" menu to fs/Kconfig.binfmt 2018-08-02 08:06:55 +09:00
MAINTAINERS USB: rio500: Remove Rio 500 kernel driver 2019-10-17 13:44:47 -07:00
Makefile Linux 4.19.102 2020-02-05 14:43:55 +00:00
README Docs: Added a pointer to the formatted docs to README 2018-03-21 09:02:53 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.