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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-24 08:46:03 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-24 08:46:03 -0700
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Merge tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrlgrafted
Pull pin control updates from Linus Walleij: "Core changes: - Use the non-blocking mux_state_try_select() in the generic MUX pin control back-end - Free pin maps on pinctrl_generic_to_map() failure in the core helpers New hardware pin control: - Qualcomm Maili TLMM SoC, PMG1110 PMIC, and Eliza LPASS LPI TLMM SoC (this is for the low power audio, LPASS = Low Power Audio SubSystem portions) - Upboard support on top of the Intel pin controller - Apple T6030 and T6031 support (just compatible strings) - Samsung Exynos 8855 SoC - Mediatek MT6858 SoC - Rockchip RK3308B and RV1106 SoCs - Airoha EN7523 and AN7563 SoCs Improvements: - Qualcomm TLMM GPIOs are unconditionally marked as wakeup capable - Qualcomm improvements on top of the Qualcomm PDC (power domain controller) irqchip improvements from tglx:s tree - Qualcomm IPQ806x and IPQ9650 non-urgent pin grop fixups - The NPCM8xx driver has been put into shape fixing many pin and group definitions - Some non-urgent Tegra 264 pin assignments are fixed up - Some non-urgent fixups to Airoha AN7581 and AN7583 registers and pin assignments, missing features etc" * tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (130 commits) dt-bindings: pinctrl: Convert TI DA850 pupd to DT schema pinctrl: meson: sync some modify from A4 pinctrl: meson: a4: Add input enable pin configuration pinctrl: realtek: rtd1625: remove unused group name spdif_sel pinctrl: realtek: rtd1625: fix base_bit for VE4 GPIO 13 dt-bindings: pinctrl: microchip,pic32mzda-pinctrl: Convert to DT schema Revert "Merge branch 'ib-rsk7204' into devel" pinctrl: rockchip: Add RV1106 pinctrl support dt-bindings: pinctrl: rockchip: Add RV1106 compatible pinctrl: rockchip: Decode drive strength in the get function pinctrl: fix PINCTRL_GENERIC_MUX not always being selectable pinctrl: airoha: add support of an7563 SoC dt-bindings: pinctrl: airoha: add support of an7563 pin controller pinctrl: airoha: try to find chip scu node by phandle first pinctrl: airoha: add support of en7523 SoC dt-bindings: pinctrl: airoha: add support of en7523 pin controller pinctrl: airoha: an7583: add support for olt pinmux pinctrl: airoha: an7583: add support for pon_alt pinmux pinctrl: airoha: an7583: add support for npu_uart pinmux dt-bindings: pinctrl: airoha: an7583: add missed features ...
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+=============
+dm-log-writes
+=============
+
+This target takes 2 devices, one to pass all IO to normally, and one to log all
+of the write operations to. This is intended for file system developers wishing
+to verify the integrity of metadata or data as the file system is written to.
+There is a log_write_entry written for every WRITE request and the target is
+able to take arbitrary data from userspace to insert into the log. The data
+that is in the WRITE requests is copied into the log to make the replay happen
+exactly as it happened originally.
+
+Log Ordering
+============
+
+We log things in order of completion once we are sure the write is no longer in
+cache. This means that normal WRITE requests are not actually logged until the
+next REQ_PREFLUSH request. This is to make it easier for userspace to replay
+the log in a way that correlates to what is on disk and not what is in cache,
+to make it easier to detect improper waiting/flushing.
+
+This works by attaching all WRITE requests to a list once the write completes.
+Once we see a REQ_PREFLUSH request we splice this list onto the request and once
+the FLUSH request completes we log all of the WRITEs and then the FLUSH. Only
+completed WRITEs, at the time the REQ_PREFLUSH is issued, are added in order to
+simulate the worst case scenario with regard to power failures. Consider the
+following example (W means write, C means complete):
+
+ W1,W2,W3,C3,C2,Wflush,C1,Cflush
+
+The log would show the following:
+
+ W3,W2,flush,W1....
+
+Again this is to simulate what is actually on disk, this allows us to detect
+cases where a power failure at a particular point in time would create an
+inconsistent file system.
+
+Any REQ_FUA requests bypass this flushing mechanism and are logged as soon as
+they complete as those requests will obviously bypass the device cache.
+
+Any REQ_OP_DISCARD requests are treated like WRITE requests. Otherwise we would
+have all the DISCARD requests, and then the WRITE requests and then the FLUSH
+request. Consider the following example:
+
+ WRITE block 1, DISCARD block 1, FLUSH
+
+If we logged DISCARD when it completed, the replay would look like this:
+
+ DISCARD 1, WRITE 1, FLUSH
+
+which isn't quite what happened and wouldn't be caught during the log replay.
+
+Target interface
+================
+
+i) Constructor
+
+ log-writes <dev_path> <log_dev_path>
+
+ ============= ==============================================
+ dev_path Device that all of the IO will go to normally.
+ log_dev_path Device where the log entries are written to.
+ ============= ==============================================
+
+ii) Status
+
+ <#logged entries> <highest allocated sector>
+
+ =========================== ========================
+ #logged entries Number of logged entries
+ highest allocated sector Highest allocated sector
+ =========================== ========================
+
+iii) Messages
+
+ mark <description>
+
+ You can use a dmsetup message to set an arbitrary mark in a log.
+ For example say you want to fsck a file system after every
+ write, but first you need to replay up to the mkfs to make sure
+ we're fsck'ing something reasonable, you would do something like
+ this::
+
+ mkfs.btrfs -f /dev/mapper/log
+ dmsetup message log 0 mark mkfs
+ <run test>
+
+ This would allow you to replay the log up to the mkfs mark and
+ then replay from that point on doing the fsck check in the
+ interval that you want.
+
+ Every log has a mark at the end labeled "dm-log-writes-end".
+
+Userspace component
+===================
+
+There is a userspace tool that will replay the log for you in various ways.
+It can be found here: https://github.com/josefbacik/log-writes
+
+Example usage
+=============
+
+Say you want to test fsync on your file system. You would do something like
+this::
+
+ TABLE="0 $(blockdev --getsz /dev/sdb) log-writes /dev/sdb /dev/sdc"
+ dmsetup create log --table "$TABLE"
+ mkfs.btrfs -f /dev/mapper/log
+ dmsetup message log 0 mark mkfs
+
+ mount /dev/mapper/log /mnt/btrfs-test
+ <some test that does fsync at the end>
+ dmsetup message log 0 mark fsync
+ md5sum /mnt/btrfs-test/foo
+ umount /mnt/btrfs-test
+
+ dmsetup remove log
+ replay-log --log /dev/sdc --replay /dev/sdb --end-mark fsync
+ mount /dev/sdb /mnt/btrfs-test
+ md5sum /mnt/btrfs-test/foo
+ <verify md5sum's are correct>
+
+ Another option is to do a complicated file system operation and verify the file
+ system is consistent during the entire operation. You could do this with:
+
+ TABLE="0 $(blockdev --getsz /dev/sdb) log-writes /dev/sdb /dev/sdc"
+ dmsetup create log --table "$TABLE"
+ mkfs.btrfs -f /dev/mapper/log
+ dmsetup message log 0 mark mkfs
+
+ mount /dev/mapper/log /mnt/btrfs-test
+ <fsstress to dirty the fs>
+ btrfs filesystem balance /mnt/btrfs-test
+ umount /mnt/btrfs-test
+ dmsetup remove log
+
+ replay-log --log /dev/sdc --replay /dev/sdb --end-mark mkfs
+ btrfsck /dev/sdb
+ replay-log --log /dev/sdc --replay /dev/sdb --start-mark mkfs \
+ --fsck "btrfsck /dev/sdb" --check fua
+
+And that will replay the log until it sees a FUA request, run the fsck command
+and if the fsck passes it will replay to the next FUA, until it is completed or
+the fsck command exists abnormally.