Commit Graph

1248726 Commits

Author SHA1 Message Date
Uwe Kleine-König
07d03559ed auxdisplay: cfag12864bfb: Convert to platform remove callback returning void
The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.

To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new(), which already returns void. Eventually after all drivers
are converted, .remove_new() will be renamed to .remove().

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Miguel Ojeda <ojeda@kernel.org>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-03-12 17:36:49 +02:00
Chris Packham
d8abf9d4ea auxdisplay: seg-led-gpio: Import linedisp namespace
The seg-led-gpio driver uses symbols from the linedisp namespace. Ensure
these are imported.

Fixes: 899383f9ec ("auxdisplay: Add 7-segment LED display driver")
Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Closes: https://lore.kernel.org/r/202403100401.IDre04gu-lkp@intel.com/
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-03-11 11:56:45 +02:00
Chris Packham
4664b0bbb6 dt-bindings: auxdisplay: Add bindings for generic 7-segment LED
Add bindings for a generic 7-segment LED display using GPIOs.

Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-03-08 14:15:47 +02:00
Chris Packham
899383f9ec auxdisplay: Add 7-segment LED display driver
Add a driver for a 7-segment LED display. At the moment only one
character is supported but it should be possible to expand this to
support more characters and/or 14-segment displays in the future.

Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-03-08 14:15:47 +02:00
Andy Shevchenko
a9bcd02fa4 auxdisplay: Add driver for MAX695x 7-segment LED controllers
Add initial driver for the MAX6958 and MAX6959 7-segment LED
controllers.

Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-02-26 20:02:35 +02:00
Andy Shevchenko
f6815c79d2 dt-bindings: auxdisplay: Add Maxim MAX6958/6959
Add initial device tree documentation for Maxim MAX6958/6959.
As per reviewer's request mention the fact of absence the reset
and power enable pins, since the hardware is quite simple.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
2024-02-26 20:02:26 +02:00
Andy Shevchenko
a459b2707a auxdisplay: ht16k33: Drop struct ht16k33_seg
The struct ht16k33_seg is repeating struct linedisp. Use the latter
directly.

Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-02-26 18:07:16 +02:00
Andy Shevchenko
815876dc0b auxdisplay: ht16k33: Switch to use line display character mapping
Since line display library supports necessary bits to map the characters
(if required), switch this driver to use that.

Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Robin van der Gracht <robin@protonic.nl>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-02-26 18:07:16 +02:00
Andy Shevchenko
0ee6eb851e auxdisplay: ht16k33: Define a few helper macros
Define a few helper macros — wrappers on container_of() — for easier
maintenance in the future. While at it, include missing container_of.h.

Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-02-26 18:07:05 +02:00
Andy Shevchenko
5a805a7827 auxdisplay: ht16k33: Move ht16k33_linedisp_ops down
We will need the update functions to be defined before
ht16k33_linedisp_ops. Move the latter down in the code.
No functional change intended.

Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Robin van der Gracht <robin@protonic.nl>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-02-26 18:02:19 +02:00
Andy Shevchenko
ef2086a9e1 auxdisplay: ht16k33: Add default to switch-cases
Currently the compiler (GCC) is able to figure out that there is no
other choices possible than those that are already listed in the
switch-cases. However, if we want to move some code to the callback,
compiler will start complaining that no default is defined. Make
sure we have all switch-cases equiped with default.

Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-02-26 18:02:19 +02:00
Andy Shevchenko
4ce026d5f4 auxdisplay: linedisp: Allocate buffer for the string
Always allocate a buffer for the currently displayed characters.
It makes the line display API simpler.

Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-02-26 18:02:19 +02:00
Andy Shevchenko
34ddc83dc7 auxdisplay: linedisp: Add support for overriding character mapping
There is already the driver using character mapping table for
7 or 14 segment display. It is possible to override it. Make
the similar in the line display library to allow other drivers
to utilise the same functionality.

Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-02-15 14:30:15 +02:00
Andy Shevchenko
70fb97c061 auxdisplay: linedisp: Provide struct linedisp_ops for future extension
Currently the line display library doesn't scale in case we want to
provide more operations. Prepare the library to take a newly created
struct linedisp_ops that scales.

Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-02-15 14:30:15 +02:00
Andy Shevchenko
fe5bd82f59 auxdisplay: linedisp: Move exported symbols to a namespace
Avoid unnecessary pollution of the global symbol namespace by
moving library functions in to a specific namespace and import
that into the drivers that make use of the functions.

For more info: https://lwn.net/Articles/760045/

Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-02-15 13:31:21 +02:00
Andy Shevchenko
6134b0be91 auxdisplay: linedisp: Add missing header(s)
Do not imply that some of the generic headers may be always included.
Instead, include explicitly what we are direct user of.

Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-02-15 13:31:21 +02:00
Andy Shevchenko
7168791fca auxdisplay: linedisp: Unshadow error codes in ->store()
kstrtox() may return different error codes.

Unshadow them in the ->store() callback to give better error report.

While at it, add missing kstrtox.h inclusion.

Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-02-15 13:31:20 +02:00
Andy Shevchenko
50d6b9d56e auxdisplay: linedisp: Use unique number for id
The absence of decrementation of linedisp_id is incorrect in two ways,
i.e. it may cause:
- an ID exhaustion
- (and if the above is addressed) a duplicate id number may be allocated
  next time a device is added

Replace above mentioned approach by using IDA framework.

Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-02-15 13:31:12 +02:00
Andy Shevchenko
2327960f0c auxdisplay: linedisp: Free allocated resources in ->release()
While there is no issue currently with the resources allocation,
the code may still be made more robust by deallocating message
in the ->release() callback.

Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-02-15 13:24:54 +02:00
Andy Shevchenko
a8fc3d587f auxdisplay: img-ascii-lcd: Make container_of() no-op for struct linedisp
Move embedded struct linedisp member to make container_of() no-op.

Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-02-15 13:24:53 +02:00
Andy Shevchenko
b33190d0fd auxdisplay: panel: Switch to use module_parport_driver()
Switch to use module_parport_driver() to reduce boilerplate code.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-02-15 13:24:53 +02:00
Krzysztof Kozlowski
4fdcbb88b1 dt-bindings: auxdisplay: hit,hd44780: use defines for GPIO flags
Improve example DTS readability by using known defines for GPIO flags.

Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-02-14 20:55:34 +02:00
Krzysztof Kozlowski
961454590d dt-bindings: auxdisplay: adjust example indentation and use generic node names
The example DTS should be indented with two or four (preferred) spaces,
as mentioned in Writing Schema document.  While re-indenting, change the
node names to somehow generic names, as expected by Devicetree
specification.

Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Ralf Schlatterbeck <rsc@runtux.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-02-14 20:55:34 +02:00
Andy Shevchenko
933feb1223 auxdisplay: Add 7 and 14 segment mappings to MAINTAINERS
The mapping files are tightly related to auxdisplay subsystem.
Add them to the MAINTAINERS database.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
2024-02-14 20:54:46 +02:00
Andy Shevchenko
021515abb9 auxdisplay: Take over maintainership, but in Odd Fixes mode
I have no time for this, but since it looks like I'm the main
contributor for the last few years to the subsystem, I'll take
it for now. Geert agreed to help me as a designated reviewer.
Let's see how it will go...

Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-02-12 16:12:20 +02:00
Linus Torvalds
6613476e22 Linux 6.8-rc1 v6.8-rc1 2024-01-21 14:11:32 -08:00
Linus Torvalds
35a4474b5c Merge tag 'bcachefs-2024-01-21' of https://evilpiepirate.org/git/bcachefs
Pull more bcachefs updates from Kent Overstreet:
 "Some fixes, Some refactoring, some minor features:

   - Assorted prep work for disk space accounting rewrite

   - BTREE_TRIGGER_ATOMIC: after combining our trigger callbacks, this
     makes our trigger context more explicit

   - A few fixes to avoid excessive transaction restarts on
     multithreaded workloads: fstests (in addition to ktest tests) are
     now checking slowpath counters, and that's shaking out a few bugs

   - Assorted tracepoint improvements

   - Starting to break up bcachefs_format.h and move on disk types so
     they're with the code they belong to; this will make room to start
     documenting the on disk format better.

   - A few minor fixes"

* tag 'bcachefs-2024-01-21' of https://evilpiepirate.org/git/bcachefs: (46 commits)
  bcachefs: Improve inode_to_text()
  bcachefs: logged_ops_format.h
  bcachefs: reflink_format.h
  bcachefs; extents_format.h
  bcachefs: ec_format.h
  bcachefs: subvolume_format.h
  bcachefs: snapshot_format.h
  bcachefs: alloc_background_format.h
  bcachefs: xattr_format.h
  bcachefs: dirent_format.h
  bcachefs: inode_format.h
  bcachefs; quota_format.h
  bcachefs: sb-counters_format.h
  bcachefs: counters.c -> sb-counters.c
  bcachefs: comment bch_subvolume
  bcachefs: bch_snapshot::btime
  bcachefs: add missing __GFP_NOWARN
  bcachefs: opts->compression can now also be applied in the background
  bcachefs: Prep work for variable size btree node buffers
  bcachefs: grab s_umount only if snapshotting
  ...
2024-01-21 14:01:12 -08:00
Linus Torvalds
4fbbed7872 Merge tag 'timers-core-2024-01-21' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer updates from Thomas Gleixner:
 "Updates for time and clocksources:

   - A fix for the idle and iowait time accounting vs CPU hotplug.

     The time is reset on CPU hotplug which makes the accumulated
     systemwide time jump backwards.

   - Assorted fixes and improvements for clocksource/event drivers"

* tag 'timers-core-2024-01-21' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  tick-sched: Fix idle and iowait sleeptime accounting vs CPU hotplug
  clocksource/drivers/ep93xx: Fix error handling during probe
  clocksource/drivers/cadence-ttc: Fix some kernel-doc warnings
  clocksource/drivers/timer-ti-dm: Fix make W=n kerneldoc warnings
  clocksource/timer-riscv: Add riscv_clock_shutdown callback
  dt-bindings: timer: Add StarFive JH8100 clint
  dt-bindings: timer: thead,c900-aclint-mtimer: separate mtime and mtimecmp regs
2024-01-21 11:14:40 -08:00
Linus Torvalds
7b297a5cc9 Merge tag 'powerpc-6.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fixes from Aneesh Kumar:

 - Increase default stack size to 32KB for Book3S

Thanks to Michael Ellerman.

* tag 'powerpc-6.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/64s: Increase default stack size to 32KB
2024-01-21 11:04:29 -08:00
Kent Overstreet
249f441f83 bcachefs: Improve inode_to_text()
Add line breaks - inode_to_text() is now much easier to read.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21 13:27:11 -05:00
Kent Overstreet
d826cc57c5 bcachefs: logged_ops_format.h
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21 13:27:11 -05:00
Kent Overstreet
8d52ba60c4 bcachefs: reflink_format.h
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21 13:27:11 -05:00
Kent Overstreet
b2fa1b633b bcachefs; extents_format.h
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21 13:27:11 -05:00
Kent Overstreet
0560eb9abf bcachefs: ec_format.h
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21 13:27:11 -05:00
Kent Overstreet
c6c4ff6507 bcachefs: subvolume_format.h
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21 13:27:11 -05:00
Kent Overstreet
8fed323b14 bcachefs: snapshot_format.h
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21 13:27:10 -05:00
Kent Overstreet
d455179fce bcachefs: alloc_background_format.h
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21 13:27:10 -05:00
Kent Overstreet
72e0801049 bcachefs: xattr_format.h
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21 13:27:10 -05:00
Kent Overstreet
7ffc4daa5f bcachefs: dirent_format.h
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21 13:27:10 -05:00
Kent Overstreet
b36425da71 bcachefs: inode_format.h
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21 13:27:10 -05:00
Kent Overstreet
82de6207fb bcachefs; quota_format.h
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21 13:27:10 -05:00
Kent Overstreet
43314801a4 bcachefs: sb-counters_format.h
bcachefs_format.h has gotten too big; let's do some organizing.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21 13:27:10 -05:00
Kent Overstreet
3a58dfbc46 bcachefs: counters.c -> sb-counters.c
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21 13:27:10 -05:00
Kent Overstreet
12207f49ef bcachefs: comment bch_subvolume
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21 13:27:10 -05:00
Kent Overstreet
d32088f2f2 bcachefs: bch_snapshot::btime
Add a field to bch_snapshot for creation time; this will be important
when we start exposing the snapshot tree to userspace.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21 13:27:10 -05:00
Kent Overstreet
7be0208fc9 bcachefs: add missing __GFP_NOWARN
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21 13:27:10 -05:00
Kent Overstreet
d7e77f53e9 bcachefs: opts->compression can now also be applied in the background
The "apply this compression method in the background" paths now use the
compression option if background_compression is not set; this means that
setting or changing the compression option will cause existing data to
be compressed accordingly in the background.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21 13:27:10 -05:00
Kent Overstreet
ec4edd7b9d bcachefs: Prep work for variable size btree node buffers
bcachefs btree nodes are big - typically 256k - and btree roots are
pinned in memory. As we're now up to 18 btrees, we now have significant
memory overhead in mostly empty btree roots.

And in the future we're going to start enforcing that certain btree node
boundaries exist, to solve lock contention issues - analagous to XFS's
AGIs.

Thus, we need to start allocating smaller btree node buffers when we
can. This patch changes code that refers to the filesystem constant
c->opts.btree_node_size to refer to the btree node buffer size -
btree_buf_bytes() - where appropriate.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21 13:27:10 -05:00
Su Yue
2acc59dd88 bcachefs: grab s_umount only if snapshotting
When I was testing mongodb over bcachefs with compression,
there is a lockdep warning when snapshotting mongodb data volume.

$ cat test.sh
prog=bcachefs

$prog subvolume create /mnt/data
$prog subvolume create /mnt/data/snapshots

while true;do
    $prog subvolume snapshot /mnt/data /mnt/data/snapshots/$(date +%s)
    sleep 1s
done

$ cat /etc/mongodb.conf
systemLog:
  destination: file
  logAppend: true
  path: /mnt/data/mongod.log

storage:
  dbPath: /mnt/data/

lockdep reports:
[ 3437.452330] ======================================================
[ 3437.452750] WARNING: possible circular locking dependency detected
[ 3437.453168] 6.7.0-rc7-custom+ #85 Tainted: G            E
[ 3437.453562] ------------------------------------------------------
[ 3437.453981] bcachefs/35533 is trying to acquire lock:
[ 3437.454325] ffffa0a02b2b1418 (sb_writers#10){.+.+}-{0:0}, at: filename_create+0x62/0x190
[ 3437.454875]
               but task is already holding lock:
[ 3437.455268] ffffa0a02b2b10e0 (&type->s_umount_key#48){.+.+}-{3:3}, at: bch2_fs_file_ioctl+0x232/0xc90 [bcachefs]
[ 3437.456009]
               which lock already depends on the new lock.

[ 3437.456553]
               the existing dependency chain (in reverse order) is:
[ 3437.457054]
               -> #3 (&type->s_umount_key#48){.+.+}-{3:3}:
[ 3437.457507]        down_read+0x3e/0x170
[ 3437.457772]        bch2_fs_file_ioctl+0x232/0xc90 [bcachefs]
[ 3437.458206]        __x64_sys_ioctl+0x93/0xd0
[ 3437.458498]        do_syscall_64+0x42/0xf0
[ 3437.458779]        entry_SYSCALL_64_after_hwframe+0x6e/0x76
[ 3437.459155]
               -> #2 (&c->snapshot_create_lock){++++}-{3:3}:
[ 3437.459615]        down_read+0x3e/0x170
[ 3437.459878]        bch2_truncate+0x82/0x110 [bcachefs]
[ 3437.460276]        bchfs_truncate+0x254/0x3c0 [bcachefs]
[ 3437.460686]        notify_change+0x1f1/0x4a0
[ 3437.461283]        do_truncate+0x7f/0xd0
[ 3437.461555]        path_openat+0xa57/0xce0
[ 3437.461836]        do_filp_open+0xb4/0x160
[ 3437.462116]        do_sys_openat2+0x91/0xc0
[ 3437.462402]        __x64_sys_openat+0x53/0xa0
[ 3437.462701]        do_syscall_64+0x42/0xf0
[ 3437.462982]        entry_SYSCALL_64_after_hwframe+0x6e/0x76
[ 3437.463359]
               -> #1 (&sb->s_type->i_mutex_key#15){+.+.}-{3:3}:
[ 3437.463843]        down_write+0x3b/0xc0
[ 3437.464223]        bch2_write_iter+0x5b/0xcc0 [bcachefs]
[ 3437.464493]        vfs_write+0x21b/0x4c0
[ 3437.464653]        ksys_write+0x69/0xf0
[ 3437.464839]        do_syscall_64+0x42/0xf0
[ 3437.465009]        entry_SYSCALL_64_after_hwframe+0x6e/0x76
[ 3437.465231]
               -> #0 (sb_writers#10){.+.+}-{0:0}:
[ 3437.465471]        __lock_acquire+0x1455/0x21b0
[ 3437.465656]        lock_acquire+0xc6/0x2b0
[ 3437.465822]        mnt_want_write+0x46/0x1a0
[ 3437.465996]        filename_create+0x62/0x190
[ 3437.466175]        user_path_create+0x2d/0x50
[ 3437.466352]        bch2_fs_file_ioctl+0x2ec/0xc90 [bcachefs]
[ 3437.466617]        __x64_sys_ioctl+0x93/0xd0
[ 3437.466791]        do_syscall_64+0x42/0xf0
[ 3437.466957]        entry_SYSCALL_64_after_hwframe+0x6e/0x76
[ 3437.467180]
               other info that might help us debug this:

[ 3437.469670] 2 locks held by bcachefs/35533:
               other info that might help us debug this:

[ 3437.467507] Chain exists of:
                 sb_writers#10 --> &c->snapshot_create_lock --> &type->s_umount_key#48

[ 3437.467979]  Possible unsafe locking scenario:

[ 3437.468223]        CPU0                    CPU1
[ 3437.468405]        ----                    ----
[ 3437.468585]   rlock(&type->s_umount_key#48);
[ 3437.468758]                                lock(&c->snapshot_create_lock);
[ 3437.469030]                                lock(&type->s_umount_key#48);
[ 3437.469291]   rlock(sb_writers#10);
[ 3437.469434]
                *** DEADLOCK ***

[ 3437.469670] 2 locks held by bcachefs/35533:
[ 3437.469838]  #0: ffffa0a02ce00a88 (&c->snapshot_create_lock){++++}-{3:3}, at: bch2_fs_file_ioctl+0x1e3/0xc90 [bcachefs]
[ 3437.470294]  #1: ffffa0a02b2b10e0 (&type->s_umount_key#48){.+.+}-{3:3}, at: bch2_fs_file_ioctl+0x232/0xc90 [bcachefs]
[ 3437.470744]
               stack backtrace:
[ 3437.470922] CPU: 7 PID: 35533 Comm: bcachefs Kdump: loaded Tainted: G            E      6.7.0-rc7-custom+ #85
[ 3437.471313] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Arch Linux 1.16.3-1-1 04/01/2014
[ 3437.471694] Call Trace:
[ 3437.471795]  <TASK>
[ 3437.471884]  dump_stack_lvl+0x57/0x90
[ 3437.472035]  check_noncircular+0x132/0x150
[ 3437.472202]  __lock_acquire+0x1455/0x21b0
[ 3437.472369]  lock_acquire+0xc6/0x2b0
[ 3437.472518]  ? filename_create+0x62/0x190
[ 3437.472683]  ? lock_is_held_type+0x97/0x110
[ 3437.472856]  mnt_want_write+0x46/0x1a0
[ 3437.473025]  ? filename_create+0x62/0x190
[ 3437.473204]  filename_create+0x62/0x190
[ 3437.473380]  user_path_create+0x2d/0x50
[ 3437.473555]  bch2_fs_file_ioctl+0x2ec/0xc90 [bcachefs]
[ 3437.473819]  ? lock_acquire+0xc6/0x2b0
[ 3437.474002]  ? __fget_files+0x2a/0x190
[ 3437.474195]  ? __fget_files+0xbc/0x190
[ 3437.474380]  ? lock_release+0xc5/0x270
[ 3437.474567]  ? __x64_sys_ioctl+0x93/0xd0
[ 3437.474764]  ? __pfx_bch2_fs_file_ioctl+0x10/0x10 [bcachefs]
[ 3437.475090]  __x64_sys_ioctl+0x93/0xd0
[ 3437.475277]  do_syscall_64+0x42/0xf0
[ 3437.475454]  entry_SYSCALL_64_after_hwframe+0x6e/0x76
[ 3437.475691] RIP: 0033:0x7f2743c313af
======================================================

In __bch2_ioctl_subvolume_create(), we grab s_umount unconditionally
and unlock it at the end of the function. There is a comment
"why do we need this lock?" about the lock coming from
commit 42d237320e ("bcachefs: Snapshot creation, deletion")
The reason is that __bch2_ioctl_subvolume_create() calls
sync_inodes_sb() which enforce locked s_umount to writeback all dirty
nodes before doing snapshot works.

Fix it by read locking s_umount for snapshotting only and unlocking
s_umount after sync_inodes_sb().

Signed-off-by: Su Yue <glass.su@suse.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21 13:27:10 -05:00
Su Yue
369acf97d6 bcachefs: kvfree bch_fs::snapshots in bch2_fs_snapshots_exit
bch_fs::snapshots is allocated by kvzalloc in __snapshot_t_mut.
It should be freed by kvfree not kfree.
Or umount will triger:

[  406.829178 ] BUG: unable to handle page fault for address: ffffe7b487148008
[  406.830676 ] #PF: supervisor read access in kernel mode
[  406.831643 ] #PF: error_code(0x0000) - not-present page
[  406.832487 ] PGD 0 P4D 0
[  406.832898 ] Oops: 0000 [#1] PREEMPT SMP PTI
[  406.833512 ] CPU: 2 PID: 1754 Comm: umount Kdump: loaded Tainted: G           OE      6.7.0-rc7-custom+ #90
[  406.834746 ] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Arch Linux 1.16.3-1-1 04/01/2014
[  406.835796 ] RIP: 0010:kfree+0x62/0x140
[  406.836197 ] Code: 80 48 01 d8 0f 82 e9 00 00 00 48 c7 c2 00 00 00 80 48 2b 15 78 9f 1f 01 48 01 d0 48 c1 e8 0c 48 c1 e0 06 48 03 05 56 9f 1f 01 <48> 8b 50 08 48 89 c7 f6 c2 01 0f 85 b0 00 00 00 66 90 48 8b 07 f6
[  406.837810 ] RSP: 0018:ffffb9d641607e48 EFLAGS: 00010286
[  406.838213 ] RAX: ffffe7b487148000 RBX: ffffb9d645200000 RCX: ffffb9d641607dc4
[  406.838738 ] RDX: 000065bb00000000 RSI: ffffffffc0d88b84 RDI: ffffb9d645200000
[  406.839217 ] RBP: ffff9a4625d00068 R08: 0000000000000001 R09: 0000000000000001
[  406.839650 ] R10: 0000000000000001 R11: 000000000000001f R12: ffff9a4625d4da80
[  406.840055 ] R13: ffff9a4625d00000 R14: ffffffffc0e2eb20 R15: 0000000000000000
[  406.840451 ] FS:  00007f0a264ffb80(0000) GS:ffff9a4e2d500000(0000) knlGS:0000000000000000
[  406.840851 ] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  406.841125 ] CR2: ffffe7b487148008 CR3: 000000018c4d2000 CR4: 00000000000006f0
[  406.841464 ] Call Trace:
[  406.841583 ]  <TASK>
[  406.841682 ]  ? __die+0x1f/0x70
[  406.841828 ]  ? page_fault_oops+0x159/0x470
[  406.842014 ]  ? fixup_exception+0x22/0x310
[  406.842198 ]  ? exc_page_fault+0x1ed/0x200
[  406.842382 ]  ? asm_exc_page_fault+0x22/0x30
[  406.842574 ]  ? bch2_fs_release+0x54/0x280 [bcachefs]
[  406.842842 ]  ? kfree+0x62/0x140
[  406.842988 ]  ? kfree+0x104/0x140
[  406.843138 ]  bch2_fs_release+0x54/0x280 [bcachefs]
[  406.843390 ]  kobject_put+0xb7/0x170
[  406.843552 ]  deactivate_locked_super+0x2f/0xa0
[  406.843756 ]  cleanup_mnt+0xba/0x150
[  406.843917 ]  task_work_run+0x59/0xa0
[  406.844083 ]  exit_to_user_mode_prepare+0x197/0x1a0
[  406.844302 ]  syscall_exit_to_user_mode+0x16/0x40
[  406.844510 ]  do_syscall_64+0x4e/0xf0
[  406.844675 ]  entry_SYSCALL_64_after_hwframe+0x6e/0x76
[  406.844907 ] RIP: 0033:0x7f0a2664e4fb

Signed-off-by: Su Yue <glass.su@suse.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21 13:27:10 -05:00