Commit Graph

211 Commits

Author SHA1 Message Date
Qu Wenruo
011b46c304 btrfs: skip subtree scan if it's too high to avoid low stall in btrfs_commit_transaction()
Btrfs qgroup has a long history of bringing performance penalty in
btrfs_commit_transaction().

Although we tried our best to migrate such impact, there is still an
unsolved call site, btrfs_drop_snapshot().

This function will find the highest shared tree block and modify its
extent ownership to do a subvolume/snapshot dropping.

Such change will affect the whole subtree, and cause tons of qgroup
dirty extents and stall btrfs_commit_transaction().

To avoid such problem, here we introduce a new sysfs interface,
/sys/fs/btrfs/<uuid>/qgroups/drop_subptree_threshold, to determine at
whether and at which level we should skip qgroup accounting for subtree
dropping.

The default value is BTRFS_MAX_LEVEL, thus every subtree drop will go
through qgroup accounting, to ensure qgroup numbers are kept as
consistent as possible.

While for performance sensitive cases, add a way to change the values to
more reasonable values like 3, to make any subtree, which is at or higher
than level 3, to mark qgroup inconsistent and skip the accounting.

The cost is obvious, the qgroup number is no longer consistent, but at
least performance is more reasonable, and users have the control.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-09-26 12:28:01 +02:00
Qu Wenruo
ed2e35d85d btrfs: sysfs: introduce global qgroup attribute group
Although we already have info kobject for each qgroup, we don't have
global qgroup info attributes to show things like enabled or
inconsistent status flags.

Add this qgroups attribute groups, and the first member is qgroup_flags,
which is a read-only attribute to show human readable qgroup flags.

The path is:
  /sys/fs/btrfs/<uuid>/qgroups/enabled
  /sys/fs/btrfs/<uuid>/qgroups/inconsistent

The output is simple, just 1 or 0.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-09-26 12:28:01 +02:00
zhang songyi
bd64f6221a btrfs: remove the unnecessary result variables
Return the sysfs_emit() and iterate_object_props() directly instead of
using unnecessary variables.

Reported-by: Zeal Robot <zealci@zte.com.cn>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: zhang songyi <zhang.songyi@zte.com.cn>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-09-26 12:28:00 +02:00
Qu Wenruo
1c56ab9919 btrfs: separate BLOCK_GROUP_TREE compat RO flag from EXTENT_TREE_V2
The problem of long mount time caused by block group item search is
already known for some time, and the solution of block group tree has
been proposed.

There is really no need to bound this feature into extent tree v2, just
introduce compat RO flag, BLOCK_GROUP_TREE, to correctly solve the
problem.

All the code handling block group root is already in the upstream
kernel, thus this patch really only needs to introduce the new compat RO
flag.

This patch introduces one extra artificial limitation on block group
tree feature, that free space cache v2 and no-holes feature must be
enabled to use this new compat RO feature.

This artificial requirement is mostly to reduce the test combinations,
and can be a guideline for future features, to mostly rely on the latest
default features.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-09-26 12:28:00 +02:00
David Sterba
fb731430be btrfs: sysfs: show discard stats and tunables in non-debug build
When discard=async was introduced there were also sysfs knobs and stats
for debugging and tuning, hidden under CONFIG_BTRFS_DEBUG. The defaults
have been set and so far seem to satisfy all users on a range of
workloads. As there are not only tunables (like iops or kbps) but also
stats tracking amount of discardable bytes, that should be available
when the async discard is on (otherwise it's not).

The stats are moved from the per-fs debug directory, so it's under
  /sys/fs/btrfs/FSID/discard

- discard_bitmap_bytes - amount of discarded bytes from data tracked as
                         bitmaps
- discard_extent_bytes - dtto but as extents
- discard_bytes_saved -
- discardable_bytes - amount of bytes that can be discarded
- discardable_extents - number of extents to be discarded
- iops_limit - tunable limit of number of discard IOs to be issued
- kbps_limit - tunable limit of kilobytes per second issued as discard IO
- max_discard_size - tunable limit for size of one IO discard request

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-09-26 12:27:57 +02:00
David Sterba
7f298f224e btrfs: sysfs: use sysfs_streq for string matching
We have own string matching helper that duplicates what sysfs_streq
does, with a slight difference that it skips initial whitespace. So far
this is used for the drive allocation policy. The initial whitespace
of written sysfs values should be rather discouraged and we should use a
standard helper.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-09-26 12:27:53 +02:00
Nikolay Borisov
74860816e8 btrfs: sysfs: remove BIG_METADATA feature files
This flag has been merged in 3.10 and is effectively always-on. Its
status depends on the host page size so there's another way to guarantee
compatibility with old kernels.

Due to a bug introduced in 6f93e834fa ("btrfs: fix upper limit for
max_inline for page size 64K") the flag is not persisted among features
in the superblock so it's not reliable.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:39 +02:00
Nikolay Borisov
0766837b0d btrfs: sysfs: remove MIXED_BACKREF feature file
This feature has been the default for about 13 year. At this point it's
safe to consider it an indispensable feature of BTRFS as such there's
no need to advertise it in sysfs. Remove the global sysfs feature file,
the per-filesystem feature file has never been there.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:39 +02:00
Ioannis Angelakopoulos
140a8ff765 btrfs: sysfs: export commit stats
Export commit stats in file

  /sys/fs/btrfs/UUID/commit_stats

with example output like:

  commits 123
  last_commit_ms 11
  max_commit_ms 150
  total_commit_ms 2000

The values are in one file so reading them at a single time will give a
more consistent view. The stats are internally tracked in nanoseconds so
the cumulative values should not suffer from rounding errors.

Writing 0 to the file 'commit_stats' will reset max_commit_ms.
Initial values are set at first mount of the filesystem.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Ioannis Angelakopoulos <iangelak@fb.com>
[ update changelog ]
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:37 +02:00
David Sterba
15dcccdb8b btrfs: sysfs: advertise zoned support among features
We've hidden the zoned support in sysfs under debug config for the first
releases but now the stability is reasonable, though not all features
have been implemented.

Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:34 +02:00
Stefan Roesch
22c55e3bbb btrfs: sysfs: add force_chunk_alloc trigger to force allocation
Adds write-only trigger to force new chunk allocation for a given block
group type. It is at

  /sys/fs/btrfs/<uuid>/allocation/<type>/force_chunk_alloc

Note: this is now only for debugging and testing and is enabled with the
      CONFIG_BTRFS_DEBUG configuration option. The transaction is
      started from sysfs context and can be problematic in some cases.

Signed-off-by: Stefan Roesch <shr@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ Changes from the original submission:
  - update changelog
  - drop unnecessary error messages
  - switch value to bool and use kstrtobool
  - move BTRFS_ATTR_W definition
  - add comment for using transaction
]
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:32 +02:00
Stefan Roesch
19fc516a51 btrfs: sysfs: export chunk size in space infos
Add new sysfs knob

  /sys/fs/btrfs/<uuid>/allocation/<type>/chunk_size.

This allows to query the chunk size and also set the chunk size.

Constraints:

- can be changed by root only
- system chunk size can't be set
- maximum chunk size is 10% of the filesystem size
- final value is rounded down to a multiple of 256M
- cannot be set on zoned filesystem

Note, that rounding and the 10% clamp will result to a different value
on filesystems smaller than 10G, typically 768M.

Signed-off-by: Stefan Roesch <shr@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ Changes to original submission:
  - document setting constraints
  - drop read-only requirement
  - drop unnecessary error messages
  - fix return values of _store callback
  - use memparse for the value
  - fix rounding down to 256M
]
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:32 +02:00
David Sterba
143823cf4d btrfs: fix typos in comments
Codespell has found a few typos.

Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:44:33 +02:00
Josef Bacik
ef972e7b5e btrfs: change the bg_reclaim_threshold valid region from 0 to 100
For the non-zoned case we may want to set the threshold for reclaim to
something below 50%.  Change the acceptable threshold from 50-100 to
0-100.

Tested-by: Pankaj Raghav <p.raghav@samsung.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:11 +02:00
Josef Bacik
bb5a098d97 btrfs: make the bg_reclaim_threshold per-space info
For non-zoned file systems it's useful to have the auto reclaim feature,
however there are different use cases for non-zoned, for example we may
not want to reclaim metadata chunks ever, only data chunks.  Move this
sysfs flag to per-space_info.  This won't affect current users because
this tunable only ever did anything for zoned, and that is currently
hidden behind BTRFS_CONFIG_DEBUG.

Tested-by: Pankaj Raghav <p.raghav@samsung.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
[ jth restore global bg_reclaim_threshold ]
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:11 +02:00
Qu Wenruo
1a42daab11 btrfs: expand subpage support to any PAGE_SIZE > 4K
With the recent change in metadata handling, we can handle metadata in
the following cases:

- nodesize < PAGE_SIZE and sectorsize < PAGE_SIZE
  Go subpage routine for both metadata and data.

- nodesize < PAGE_SIZE and sectorsize >= PAGE_SIZE
  Invalid case for now. As we require nodesize >= sectorsize.

- nodesize >= PAGE_SIZE and sectorsize < PAGE_SIZE
  Go subpage routine for data, but regular page routine for metadata.

- nodesize >= PAGE_SIZE and sectorsize >= PAGE_SIZE
  Go regular page routine for both metadata and data.

Now we can handle any sectorsize < PAGE_SIZE, plus the existing
sectorsize == PAGE_SIZE support.

But here we introduce an artificial limit, any PAGE_SIZE > 4K case, we
will only support 4K and PAGE_SIZE as sector size.

The idea here is to reduce the test combinations, and push 4K as the
default standard in the future.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:11 +02:00
David Sterba
3e1ad19638 btrfs: sysfs: export the balance paused state of exclusive operation
The new state allowing device addition with paused balance is not
exported to user space so it can't recognize it and actually start the
operation.

Fixes: efc0e69c2f ("btrfs: introduce exclusive operation BALANCE_PAUSED state")
CC: stable@vger.kernel.org # 5.17
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-05 21:05:56 +02:00
David Sterba
a55e65b80e btrfs: replace BUILD_BUG_ON by static_assert
The static_assert introduced in 6bab69c650 ("build_bug.h: add wrapper
for _Static_assert") has been supported by compilers for a long time
(gcc 4.6, clang 3.0) and can be used in header files. We don't need to
put BUILD_BUG_ON to random functions but rather keep it next to the
definition.

The exception here is the UAPI header btrfs_tree.h that could be
potentially included by userspace code and the static assert is not
defined (nor used in any other header).

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-03-14 13:13:49 +01:00
Josef Bacik
2c7d2a2302 btrfs: add definition for EXTENT_TREE_V2
This adds the initial definition of the EXTENT_TREE_V2 incompat feature
flag.  This also hides the support behind CONFIG_BTRFS_DEBUG.

THIS IS A IN DEVELOPMENT FORMAT CHANGE, DO NOT USE UNLESS YOU ARE A
DEVELOPER OR A TESTER.

The format is in flux and will be added in stages, any fs will need to
be re-made between updates to the format.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-03-14 13:13:48 +01:00
Anand Jain
a26d60dedf btrfs: sysfs: add devinfo/fsid to retrieve actual fsid from the device
In the case of the seed device, the fsid can be different from the mounted
sprout fsid.  The userland has to read the device superblock to know the
fsid but, that idea fails if the device is missing. So add a sysfs
interface devinfo/<devid>/fsid to show the fsid of the device.

For example:
  $ cd /sys/fs/btrfs/b10b02a5-f9de-4276-b9e8-2bfd09a578a8

  $ cat devinfo/1/fsid
  c44d771f-639d-4df3-99ec-5bc7ad2af93b
  $ cat  devinfo/3/fsid
  b10b02a5-f9de-4276-b9e8-2bfd09a578a8

Though it's related to seeding, the name of the sysfs file is plain fsid as it
matches what blkid says.  A path to the device's fsid will aid scripting.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-01-07 14:18:25 +01:00
Anand Jain
020e527758 btrfs: sysfs: convert scnprintf and snprintf to sysfs_emit
Commit 2efc459d06 ("sysfs: Add sysfs_emit and sysfs_emit_at to format
sysfs out") merged in 5.10 introduced two new functions sysfs_emit() and
sysfs_emit_at() which are aware of the PAGE_SIZE limit of the output
buffer.

Use the above two new functions instead of scnprintf() and snprintf()
in various sysfs show().

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26 19:08:07 +02:00
Anand Jain
e7849e33cf btrfs: sysfs: document structures and their associated files
Sysfs file has grown big. It takes some time to locate the correct
struct attribute to add new files. Create a table and map the struct
attribute to its sysfs path.

Also, fix the comment about the debug sysfs path.  And add the comments
to the attributes instead of attribute group, where sysfs file names are
defined.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:12 +02:00
Johannes Thumshirn
77233c2d2e btrfs: zoned: allow disabling of zone auto reclaim
Automatically reclaiming dirty zones might not always be desired for all
workloads, especially as there are currently still some rough edges with
the relocation code on zoned filesystems.

Allow disabling zone auto reclaim on a per filesystem basis by writing 0
as the threshold value.

Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:11 +02:00
Boris Burkov
146054090b btrfs: initial fsverity support
Add support for fsverity in btrfs. To support the generic interface in
fs/verity, we add two new item types in the fs tree for inodes with
verity enabled. One stores the per-file verity descriptor and btrfs
verity item and the other stores the Merkle tree data itself.

Verity checking is done in end_page_read just before a page is marked
uptodate. This naturally handles a variety of edge cases like holes,
preallocated extents, and inline extents. Some care needs to be taken to
not try to verity pages past the end of the file, which are accessed by
the generic buffered file reading code under some circumstances like
reading to the end of the last page and trying to read again. Direct IO
on a verity file falls back to buffered reads.

Verity relies on PageChecked for the Merkle tree data itself to avoid
re-walking up shared paths in the tree. For this reason, we need to
cache the Merkle tree data. Since the file is immutable after verity is
turned on, we can cache it at an index past EOF.

Use the new inode ro_flags to store verity on the inode item, so that we
can enable verity on a file, then rollback to an older kernel and still
mount the file system and read the file. Since we can't safely write the
file anymore without ruining the invariants of the Merkle tree, we mark
a ro_compat flag on the file system when a file has verity enabled.

Acked-by: Eric Biggers <ebiggers@google.com>
Co-developed-by: Chris Mason <clm@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
Signed-off-by: Boris Burkov <boris@bur.io>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:09 +02:00
Qu Wenruo
95ea0486b2 btrfs: allow read-write for 4K sectorsize on 64K page size systems
Since now we support data and metadata read-write for subpage, remove
the RO requirement for subpage mount.

There are some extra limitations though:

- For now, subpage RW mount is still considered experimental
  Thus that mount warning will still be there.

- No compression support
  There are still quite some PAGE_SIZE hard coded and quite some call
  sites use extent_clear_unlock_delalloc() to unlock locked_page.
  This will screw up subpage helpers.

  Now for subpage RW mount, no matter what mount option or inode attr is
  set, all writes will not be compressed.  Although reading compressed
  data has no problem.

- No defrag for subpage case
  The defrag support for subpage case will come in later patches, which
  will also rework the defrag workflow.

- No inline extent will be created
  This is mostly due to the fact that filemap_fdatawrite_range() will
  trigger more write than the range specified.
  In fallocate calls, this behavior can make us to writeback which can
  be inlined, before we enlarge the i_size.

  This is a very special corner case, and even current btrfs check won't
  report error on such inline extent + regular extent.
  But considering how much effort has been put to prevent such inline +
  regular, I'd prefer to cut off inline extent completely until we have
  a good solution.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:06 +02:00
Josef Bacik
138a12d865 btrfs: rip out btrfs_space_info::total_bytes_pinned
We used this in may_commit_transaction() in order to determine if we
needed to commit the transaction.  However we no longer have that logic
and thus have no use of this counter anymore, so delete it.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-22 14:55:25 +02:00
David Sterba
da658b5708 btrfs: sysfs: export dev stats in devinfo directory
The device stats can be read by ioctl, wrapped by command 'btrfs device
stats'. Provide another source where to read the information in
/sys/fs/btrfs/FSID/devinfo/DEVID/error_stats . The format is a list of
'key value' pairs one per line, which is common in other stat files.
The names are the same as used in other device stat outputs.

The stats are all in one file as it's the snapshot of all available
stats. The 'one value per file' format is not very suitable here. The
stats should be valid right after the stats item is read from disk,
shortly after initializing the device.

In case the stats are not yet valid, print just 'invalid' as the file
contents.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-22 14:11:57 +02:00
David Sterba
8c5ec99561 btrfs: sysfs: fix format string for some discard stats
The type of discard_bitmap_bytes and discard_extent_bytes is u64 so the
format should be %llu, though the actual values would hardly ever
overflow to negative values.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21 15:19:06 +02:00
David Sterba
eb3b505366 btrfs: scrub: per-device bandwidth control
Add sysfs interface to limit io during scrub. We relied on the ionice
interface to do that, eg. the idle class let the system usable while
scrub was running. This has changed when mq-deadline got widespread and
did not implement the scheduling classes. That was a CFQ thing that got
deleted. We've got numerous complaints from users about degraded
performance.

Currently only BFQ supports that but it's not a common scheduler and we
can't ask everybody to switch to it.

Alternatively the cgroup io limiting can be used but that also a
non-trivial setup (v2 required, the controller must be enabled on the
system). This can still be used if desired.

Other ideas that have been explored: piggy-back on ionice (that is set
per-process and is accessible) and interpret the class and classdata as
bandwidth limits, but this does not have enough flexibility as there are
only 8 allowed and we'd have to map fixed limits to each value. Also
adjusting the value would need to lookup the process that currently runs
scrub on the given device, and the value is not sticky so would have to
be adjusted each time scrub runs.

Running out of options, sysfs does not look that bad:

- it's accessible from scripts, or udev rules
- the name is similar to what MD-RAID has
  (/proc/sys/dev/raid/speed_limit_max or /sys/block/mdX/md/sync_speed_max)
- the value is sticky at least for filesystem mount time
- adjusting the value has immediate effect
- sysfs is available in constrained environments (eg. system rescue)
- the limit also applies to device replace

Sysfs:

- raw value is in bytes
- values written to the file accept suffixes like K, M
- file is in the per-device directory /sys/fs/btrfs/FSID/devinfo/DEVID/scrub_speed_max
- 0 means use default priority of IO

The scheduler is a simple deadline one and the accuracy is up to nearest
128K.

Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21 15:19:05 +02:00
Johannes Thumshirn
18bb8bbf13 btrfs: zoned: automatically reclaim zones
When a file gets deleted on a zoned file system, the space freed is not
returned back into the block group's free space, but is migrated to
zone_unusable.

As this zone_unusable space is behind the current write pointer it is not
possible to use it for new allocations. In the current implementation a
zone is reset once all of the block group's space is accounted as zone
unusable.

This behaviour can lead to premature ENOSPC errors on a busy file system.

Instead of only reclaiming the zone once it is completely unusable,
kick off a reclaim job once the amount of unusable bytes exceeds a user
configurable threshold between 51% and 100%. It can be set per mounted
filesystem via the sysfs tunable bg_reclaim_threshold which is set to 75%
by default.

Similar to reclaiming unused block groups, these dirty block groups are
added to a to_reclaim list and then on a transaction commit, the reclaim
process is triggered but after we deleted unused block groups, which will
free space for the relocation process.

Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-20 20:46:31 +02:00
Qu Wenruo
fc57ad8d33 btrfs: add sysfs interface for supported sectorsize
Export supported sector sizes in /sys/fs/btrfs/features/supported_sectorsizes.

Currently all architectures have PAGE_SIZE, There's some disparity
between read-only and read-write support but that will be unified in the
future so there's only one file exporting the size.

The read-only support for systems with 64K pages also works for 4K
sector size.

This new sysfs interface would help eg. mkfs.btrfs to print more
accurate warnings about potentially incompatible option combinations.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:18 +02:00
Naohiro Aota
169e0da91a btrfs: zoned: track unusable bytes for zones
In a zoned filesystem a once written then freed region is not usable
until the underlying zone has been reset. So we need to distinguish such
unusable space from usable free space.

Therefore we need to introduce the "zone_unusable" field to the block
group structure, and "bytes_zone_unusable" to the space_info structure
to track the unusable space.

Pinned bytes are always reclaimed to the unusable space. But, when an
allocated region is returned before using e.g., the block group becomes
read-only between allocation time and reservation time, we can safely
return the region to the block group. For the situation, this commit
introduces "btrfs_add_free_space_unused". This behaves the same as
btrfs_add_free_space() on regular filesystem. On zoned filesystems, it
rewinds the allocation offset.

Because the read-only bytes tracks free but unusable bytes when the block
group is read-only, we need to migrate the zone_unusable bytes to
read-only bytes when a block group is marked read-only.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-09 02:46:03 +01:00
Linus Torvalds
ac7ac4618c for-5.11/block-2020-12-14
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Merge tag 'for-5.11/block-2020-12-14' of git://git.kernel.dk/linux-block

Pull block updates from Jens Axboe:
 "Another series of killing more code than what is being added, again
  thanks to Christoph's relentless cleanups and tech debt tackling.

  This contains:

   - blk-iocost improvements (Baolin Wang)

   - part0 iostat fix (Jeffle Xu)

   - Disable iopoll for split bios (Jeffle Xu)

   - block tracepoint cleanups (Christoph Hellwig)

   - Merging of struct block_device and hd_struct (Christoph Hellwig)

   - Rework/cleanup of how block device sizes are updated (Christoph
     Hellwig)

   - Simplification of gendisk lookup and removal of block device
     aliasing (Christoph Hellwig)

   - Block device ioctl cleanups (Christoph Hellwig)

   - Removal of bdget()/blkdev_get() as exported API (Christoph Hellwig)

   - Disk change rework, avoid ->revalidate_disk() (Christoph Hellwig)

   - sbitmap improvements (Pavel Begunkov)

   - Hybrid polling fix (Pavel Begunkov)

   - bvec iteration improvements (Pavel Begunkov)

   - Zone revalidation fixes (Damien Le Moal)

   - blk-throttle limit fix (Yu Kuai)

   - Various little fixes"

* tag 'for-5.11/block-2020-12-14' of git://git.kernel.dk/linux-block: (126 commits)
  blk-mq: fix msec comment from micro to milli seconds
  blk-mq: update arg in comment of blk_mq_map_queue
  blk-mq: add helper allocating tagset->tags
  Revert "block: Fix a lockdep complaint triggered by request queue flushing"
  nvme-loop: use blk_mq_hctx_set_fq_lock_class to set loop's lock class
  blk-mq: add new API of blk_mq_hctx_set_fq_lock_class
  block: disable iopoll for split bio
  block: Improve blk_revalidate_disk_zones() checks
  sbitmap: simplify wrap check
  sbitmap: replace CAS with atomic and
  sbitmap: remove swap_lock
  sbitmap: optimise sbitmap_deferred_clear()
  blk-mq: skip hybrid polling if iopoll doesn't spin
  blk-iocost: Factor out the base vrate change into a separate function
  blk-iocost: Factor out the active iocgs' state check into a separate function
  blk-iocost: Move the usage ratio calculation to the correct place
  blk-iocost: Remove unnecessary advance declaration
  blk-iocost: Fix some typos in comments
  blktrace: fix up a kerneldoc comment
  block: remove the request_queue to argument request based tracepoints
  ...
2020-12-16 12:57:51 -08:00
Naohiro Aota
7b3d5a90cb btrfs: introduce ZONED feature flag
This patch introduces the ZONED incompat flag. The flag indicates that
the volume management will satisfy the constraints imposed by
host-managed zoned block devices (aligned chunk allocation, append-only
updates, reset zone after filled).

As the zoned support will happen incrementally due to enhancing some
core infrastructure like super block writes, tree-log, raid support, the
feature will appear in sysfs only on debug builds. It will be enabled
once the support is feature complete and applications can reliably check
whether zoned support is present or not.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-12-08 15:54:16 +01:00
Tom Rix
445d8ab53f btrfs: sysfs: remove unneeded semicolon
A semicolon is not needed after a switch statement.

Signed-off-by: Tom Rix <trix@redhat.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-12-08 15:54:13 +01:00
Pavel Begunkov
3e48d8d254 btrfs: discard: reschedule work after sysfs param update
After sysfs updates discard's iops_limit or kbps_limit it also needs to
adjust current timer through rescheduling, otherwise the discard work
may wait for a long time for the previous timer to expire or bumped by
someone else.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-12-08 15:54:05 +01:00
Anand Jain
3d8cc17a05 btrfs: sysfs: add per-fs attribute for read policy
Add

 /sys/fs/btrfs/UUID/read_policy

attribute so that the read policy for the raid1, raid1c34 and raid10 can
be tuned.

When this attribute is read, it will show all available policies, with
active policy in [ ]. The read_policy attribute can be written using one
of the items listed in there.

For example:
  $ cat /sys/fs/btrfs/UUID/read_policy
  [pid]
  $ echo pid > /sys/fs/btrfs/UUID/read_policy

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-12-08 15:53:45 +01:00
Anand Jain
aaefed2078 btrfs: add helper for string match ignoring leading/trailing whitespace
Add a generic helper to match the string in a given buffer, and ignore
the leading and trailing whitespace.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ rename variables, add comments ]
Signed-off-by: David Sterba <dsterba@suse.com>
2020-12-08 15:53:44 +01:00
Josef Bacik
9037d3cbcb btrfs: introduce mount option rescue=all
Now that we have the building blocks for some better recovery options
with corrupted file systems, add a rescue=all option to enable all of
the relevant rescue options.  This will allow distros to simply default
to rescue=all for the "oh dear lord the world's on fire" recovery
without needing to know all the different options that we have and may
add in the future.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-12-08 15:53:42 +01:00
Josef Bacik
882dbe0cec btrfs: introduce mount option rescue=ignoredatacsums
There are cases where you can end up with bad data csums because of
misbehaving applications.  This happens when an application modifies a
buffer in-flight when doing an O_DIRECT write.  In order to recover the
file we need a way to turn off data checksums so you can copy the file
off, and then you can delete the file and restore it properly later.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-12-08 15:53:42 +01:00
Josef Bacik
42437a6386 btrfs: introduce mount option rescue=ignorebadroots
In the face of extent root corruption, or any other core fs wide root
corruption we will fail to mount the file system.  This makes recovery
kind of a pain, because you need to fall back to userspace tools to
scrape off data.  Instead provide a mechanism to gracefully handle bad
roots, so we can at least mount read-only and possibly recover data from
the file system.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-12-08 15:53:41 +01:00
Josef Bacik
ceafe3cc39 btrfs: sysfs: export supported rescue= mount options
We're going to be adding a variety of different rescue options, we
should advertise which ones we support to make user spaces life easier
in the future.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-12-08 15:53:40 +01:00
Anand Jain
089c8b0551 btrfs: sysfs: export filesystem generation
Matching with the information that's available from the ioctl
FS_INFO, add generation to the per-filesystem directory
/sys/fs/btrfs/UUID/generation, which could be used by scripts.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-12-07 16:23:59 +01:00
Christoph Hellwig
8d65269fe8 block: add a bdev_kobj helper
Add a little helper to find the kobject for a struct block_device.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Coly Li <colyli@suse.de>		[bcache]
Acked-by: David Sterba <dsterba@suse.com>	[btrfs]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-12-01 14:53:39 -07:00
Josef Bacik
49ea112da0 btrfs: do not create raid sysfs entries under any locks
While running xfstests btrfs/177 I got the following lockdep splat

  ======================================================
  WARNING: possible circular locking dependency detected
  5.9.0-rc3+ #5 Not tainted
  ------------------------------------------------------
  kswapd0/100 is trying to acquire lock:
  ffff97066aa56760 (&delayed_node->mutex){+.+.}-{3:3}, at: __btrfs_release_delayed_node.part.0+0x3f/0x330

  but task is already holding lock:
  ffffffff9fd74700 (fs_reclaim){+.+.}-{0:0}, at: __fs_reclaim_acquire+0x5/0x30

  which lock already depends on the new lock.

  the existing dependency chain (in reverse order) is:

  -> #3 (fs_reclaim){+.+.}-{0:0}:
	 fs_reclaim_acquire+0x65/0x80
	 slab_pre_alloc_hook.constprop.0+0x20/0x200
	 kmem_cache_alloc+0x37/0x270
	 alloc_inode+0x82/0xb0
	 iget_locked+0x10d/0x2c0
	 kernfs_get_inode+0x1b/0x130
	 kernfs_get_tree+0x136/0x240
	 sysfs_get_tree+0x16/0x40
	 vfs_get_tree+0x28/0xc0
	 path_mount+0x434/0xc00
	 __x64_sys_mount+0xe3/0x120
	 do_syscall_64+0x33/0x40
	 entry_SYSCALL_64_after_hwframe+0x44/0xa9

  -> #2 (kernfs_mutex){+.+.}-{3:3}:
	 __mutex_lock+0x7e/0x7e0
	 kernfs_add_one+0x23/0x150
	 kernfs_create_dir_ns+0x7a/0xb0
	 sysfs_create_dir_ns+0x60/0xb0
	 kobject_add_internal+0xc0/0x2c0
	 kobject_add+0x6e/0x90
	 btrfs_sysfs_add_block_group_type+0x102/0x160
	 btrfs_make_block_group+0x167/0x230
	 btrfs_alloc_chunk+0x54f/0xb80
	 btrfs_chunk_alloc+0x18e/0x3a0
	 find_free_extent+0xdf6/0x1210
	 btrfs_reserve_extent+0xb3/0x1b0
	 btrfs_alloc_tree_block+0xb0/0x310
	 alloc_tree_block_no_bg_flush+0x4a/0x60
	 __btrfs_cow_block+0x11a/0x530
	 btrfs_cow_block+0x104/0x220
	 btrfs_search_slot+0x52e/0x9d0
	 btrfs_insert_empty_items+0x64/0xb0
	 btrfs_new_inode+0x225/0x730
	 btrfs_create+0xab/0x1f0
	 lookup_open.isra.0+0x52d/0x690
	 path_openat+0x2a7/0x9e0
	 do_filp_open+0x75/0x100
	 do_sys_openat2+0x7b/0x130
	 __x64_sys_openat+0x46/0x70
	 do_syscall_64+0x33/0x40
	 entry_SYSCALL_64_after_hwframe+0x44/0xa9

  -> #1 (&fs_info->chunk_mutex){+.+.}-{3:3}:
	 __mutex_lock+0x7e/0x7e0
	 btrfs_chunk_alloc+0x125/0x3a0
	 find_free_extent+0xdf6/0x1210
	 btrfs_reserve_extent+0xb3/0x1b0
	 btrfs_alloc_tree_block+0xb0/0x310
	 alloc_tree_block_no_bg_flush+0x4a/0x60
	 __btrfs_cow_block+0x11a/0x530
	 btrfs_cow_block+0x104/0x220
	 btrfs_search_slot+0x52e/0x9d0
	 btrfs_lookup_inode+0x2a/0x8f
	 __btrfs_update_delayed_inode+0x80/0x240
	 btrfs_commit_inode_delayed_inode+0x119/0x120
	 btrfs_evict_inode+0x357/0x500
	 evict+0xcf/0x1f0
	 do_unlinkat+0x1a9/0x2b0
	 do_syscall_64+0x33/0x40
	 entry_SYSCALL_64_after_hwframe+0x44/0xa9

  -> #0 (&delayed_node->mutex){+.+.}-{3:3}:
	 __lock_acquire+0x119c/0x1fc0
	 lock_acquire+0xa7/0x3d0
	 __mutex_lock+0x7e/0x7e0
	 __btrfs_release_delayed_node.part.0+0x3f/0x330
	 btrfs_evict_inode+0x24c/0x500
	 evict+0xcf/0x1f0
	 dispose_list+0x48/0x70
	 prune_icache_sb+0x44/0x50
	 super_cache_scan+0x161/0x1e0
	 do_shrink_slab+0x178/0x3c0
	 shrink_slab+0x17c/0x290
	 shrink_node+0x2b2/0x6d0
	 balance_pgdat+0x30a/0x670
	 kswapd+0x213/0x4c0
	 kthread+0x138/0x160
	 ret_from_fork+0x1f/0x30

  other info that might help us debug this:

  Chain exists of:
    &delayed_node->mutex --> kernfs_mutex --> fs_reclaim

   Possible unsafe locking scenario:

	 CPU0                    CPU1
	 ----                    ----
    lock(fs_reclaim);
				 lock(kernfs_mutex);
				 lock(fs_reclaim);
    lock(&delayed_node->mutex);

   *** DEADLOCK ***

  3 locks held by kswapd0/100:
   #0: ffffffff9fd74700 (fs_reclaim){+.+.}-{0:0}, at: __fs_reclaim_acquire+0x5/0x30
   #1: ffffffff9fd65c50 (shrinker_rwsem){++++}-{3:3}, at: shrink_slab+0x115/0x290
   #2: ffff9706629780e0 (&type->s_umount_key#36){++++}-{3:3}, at: super_cache_scan+0x38/0x1e0

  stack backtrace:
  CPU: 1 PID: 100 Comm: kswapd0 Not tainted 5.9.0-rc3+ #5
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-2.fc32 04/01/2014
  Call Trace:
   dump_stack+0x8b/0xb8
   check_noncircular+0x12d/0x150
   __lock_acquire+0x119c/0x1fc0
   lock_acquire+0xa7/0x3d0
   ? __btrfs_release_delayed_node.part.0+0x3f/0x330
   __mutex_lock+0x7e/0x7e0
   ? __btrfs_release_delayed_node.part.0+0x3f/0x330
   ? __btrfs_release_delayed_node.part.0+0x3f/0x330
   ? lock_acquire+0xa7/0x3d0
   ? find_held_lock+0x2b/0x80
   __btrfs_release_delayed_node.part.0+0x3f/0x330
   btrfs_evict_inode+0x24c/0x500
   evict+0xcf/0x1f0
   dispose_list+0x48/0x70
   prune_icache_sb+0x44/0x50
   super_cache_scan+0x161/0x1e0
   do_shrink_slab+0x178/0x3c0
   shrink_slab+0x17c/0x290
   shrink_node+0x2b2/0x6d0
   balance_pgdat+0x30a/0x670
   kswapd+0x213/0x4c0
   ? _raw_spin_unlock_irqrestore+0x41/0x50
   ? add_wait_queue_exclusive+0x70/0x70
   ? balance_pgdat+0x670/0x670
   kthread+0x138/0x160
   ? kthread_create_worker_on_cpu+0x40/0x40
   ret_from_fork+0x1f/0x30

This happens because when we link in a block group with a new raid index
type we'll create the corresponding sysfs entries for it.  This is
problematic because while restriping we're holding the chunk_mutex, and
while mounting we're holding the tree locks.

Fixing this isn't pretty, we move the call to the sysfs stuff into the
btrfs_create_pending_block_groups() work, where we're not holding any
locks.  This creates a slight race where other threads could see that
there's no sysfs kobj for that raid type, and race to create the
sysfs dir.  Fix this by wrapping the creation in space_info->lock, so we
only get one thread calling kobject_add() for the new directory.  We
don't worry about the lock on cleanup as it only gets deleted on
unmount.

On mount it's more straightforward, we loop through the space_infos
already, just check every raid index in each space_info and added the
sysfs entries for the corresponding block groups.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-10-07 12:13:19 +02:00
Omar Sandoval
7573df5547 btrfs: sysfs: export supported send stream version
This reports the latest send stream version supported by the kernel as
the feature in /sys/fs/btrfs/features/send_stream_version .

Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-10-07 12:13:17 +02:00
Anand Jain
7ad3912a70 btrfs: handle errors in btrfs_sysfs_add_fs_devices
btrfs_sysfs_add_fs_devices() is called by btrfs_sysfs_add_mounted().
btrfs_sysfs_add_mounted() assumes that btrfs_sysfs_add_fs_devices() will
either add sysfs entries for all the devices or none. So this patch keeps up
to its caller expecatation and cleans up the created sysfs entries if it
has to fail at some device in the list.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-10-07 12:12:22 +02:00
Anand Jain
30b0e4e0e3 btrfs: initialize sysfs devid and device link for seed device
We don't initialize the sysfs devid kobject and device-link yet for the
seed devices in an sprouted filesystem.
So this patch initializes the seed device devid kobject and the device
link in the sysfs.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-10-07 12:12:21 +02:00
Anand Jain
53f8a74cbe btrfs: split and refactor btrfs_sysfs_remove_devices_dir
Similar to btrfs_sysfs_add_devices_dir()'s refactoring, split
btrfs_sysfs_remove_devices_dir() so that we don't have to use the device
argument to indicate whether to free all devices or just one device.

Export btrfs_sysfs_remove_device() as device operations outside of
sysfs.c now calls this instead of btrfs_sysfs_remove_devices_dir().

btrfs_sysfs_remove_devices_dir() is renamed to
btrfs_sysfs_remove_fs_devices() to suite its new role.

Now, no one outside of sysfs.c calls btrfs_sysfs_remove_fs_devices()
so it is redeclared s static. And the same function had to be moved
before its first caller.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-10-07 12:12:21 +02:00
Anand Jain
cd36da2e7e btrfs: simplify parameters of btrfs_sysfs_add_devices_dir
When we add a device we need to add it to sysfs, so instead of using the
btrfs_sysfs_add_devices_dir() fs_devices argument to specify whether to
add a device or all of fs_devices, call the helper function directly
btrfs_sysfs_add_device() and thus make it non-static.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-10-07 12:12:21 +02:00