Commit Graph

1750 Commits

Author SHA1 Message Date
Qu Wenruo
af32d3632e btrfs: check-integrity: remove btrfsic_mount() function
The function btrfsic_mount() is part of the deprecated check-integrity
functionality.

Now let's remove the main entry point of check-integrity, and thankfully
most of the check-integrity code is self-contained inside
check-integrity.c, we can safely remove the function without huge
changes to btrfs code base.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-10-12 16:44:05 +02:00
Qu Wenruo
51cf580c23 btrfs: check-integrity: remove btrfsic_check_bio() function
The function btrfsic_check_bio() is part of the deprecated
check-integrity functionality.

Now let's remove the main entry point of check-integrity, and thankfully
most of the check-integrity code is self-contained inside
check-integrity.c, we can safely remove the function without huge
changes to btrfs code base.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-10-12 16:44:05 +02:00
David Sterba
9580503bcb btrfs: reformat remaining kdoc style comments
Function name in the comment does not bring much value to code not
exposed as API and we don't stick to the kdoc format anymore. Update
formatting of parameter descriptions.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-10-12 16:44:04 +02:00
Anand Jain
f7361d8c3f btrfs: sipmlify uuid parameters of alloc_fs_devices()
Among all the callers, only the device_list_add() function uses the
second argument of alloc_fs_devices(). It passes metadata_uuid when
available, otherwise, it passes NULL. And in turn, alloc_fs_devices()
is designed to copy either metadata_uuid or fsid into
fs_devices::metadata_uuid.

So remove the second argument in alloc_fs_devices(), and always copy the
fsid.  In the caller device_list_add() function, we will overwrite it
with metadata_uuid when it is available.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-10-12 16:44:02 +02:00
Qu Wenruo
5e0e879926 btrfs: fix a compilation error if DEBUG is defined in btree_dirty_folio
[BUG]
After commit 72a69cd030 ("btrfs: subpage: pack all subpage bitmaps
into a larger bitmap"), the DEBUG section of btree_dirty_folio() would
no longer compile.

[CAUSE]
If DEBUG is defined, we would do extra checks for btree_dirty_folio(),
mostly to make sure the range we marked dirty has an extent buffer and
that extent buffer is dirty.

For subpage, we need to iterate through all the extent buffers covered
by that page range, and make sure they all matches the criteria.

However commit 72a69cd030 ("btrfs: subpage: pack all subpage bitmaps
into a larger bitmap") changes how we store the bitmap, we pack all the
16 bits bitmaps into a larger bitmap, which would save some space.

This means we no longer have btrfs_subpage::dirty_bitmap, instead the
dirty bitmap is starting at btrfs_subpage_info::dirty_offset, and has a
length of btrfs_subpage_info::bitmap_nr_bits.

[FIX]
Although I'm not sure if it still makes sense to maintain such code, at
least let it compile.

This patch would let us test the bits one by one through the bitmaps.

CC: stable@vger.kernel.org # 6.1+
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-09-08 14:11:04 +02:00
Josef Bacik
77d20c685b btrfs: do not block starts waiting on previous transaction commit
Internally I got a report of very long stalls on normal operations like
creating a new file when auto relocation was running.  The reporter used
the 'bpf offcputime' tracer to show that we would get stuck in
start_transaction for 5 to 30 seconds, and were always being woken up by
the transaction commit.

Using my timing-everything script, which times how long a function takes
and what percentage of that total time is taken up by its children, I
saw several traces like this

1083 took 32812902424 ns
        29929002926 ns 91.2110% wait_for_commit_duration
        25568 ns 7.7920e-05% commit_fs_roots_duration
        1007751 ns 0.00307% commit_cowonly_roots_duration
        446855602 ns 1.36182% btrfs_run_delayed_refs_duration
        271980 ns 0.00082% btrfs_run_delayed_items_duration
        2008 ns 6.1195e-06% btrfs_apply_pending_changes_duration
        9656 ns 2.9427e-05% switch_commit_roots_duration
        1598 ns 4.8700e-06% btrfs_commit_device_sizes_duration
        4314 ns 1.3147e-05% btrfs_free_log_root_tree_duration

Here I was only tracing functions that happen where we are between
START_COMMIT and UNBLOCKED in order to see what would be keeping us
blocked for so long.  The wait_for_commit() we do is where we wait for a
previous transaction that hasn't completed it's commit.  This can
include all of the unpin work and other cleanups, which tends to be the
longest part of our transaction commit.

There is no reason we should be blocking new things from entering the
transaction at this point, it just adds to random latency spikes for no
reason.

Fix this by adding a PREP stage.  This allows us to properly deal with
multiple committers coming in at the same time, we retain the behavior
that the winner waits on the previous transaction and the losers all
wait for this transaction commit to occur.  Nothing else is blocked
during the PREP stage, and then once the wait is complete we switch to
COMMIT_START and all of the same behavior as before is maintained.

Reviewed-by: Filipe Manana <fdmanana@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>
2023-09-08 14:10:49 +02:00
Anand Jain
67bc5ad04b btrfs: drop redundant check to use fs_devices::metadata_uuid
fs_devices::metadata_uuid value is already updated based on the
super_block::METADATA_UUID flag for either fsid or metadata_uuid as
appropriate. So, fs_devices::metadata_uuid can be used directly.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.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>
2023-08-21 14:54:48 +02:00
Anand Jain
6bfe3959b0 btrfs: compare the correct fsid/metadata_uuid in btrfs_validate_super
The function btrfs_validate_super() should verify the metadata_uuid in
the provided superblock argument. Because, all its callers expect it to
do that.

Such as in the following stacks:

  write_all_supers()
   sb = fs_info->super_for_commit;
   btrfs_validate_write_super(.., sb)
     btrfs_validate_super(.., sb, ..)

  scrub_one_super()
	btrfs_validate_super(.., sb, ..)

And
   check_dev_super()
	btrfs_validate_super(.., sb, ..)

However, it currently verifies the fs_info::super_copy::metadata_uuid
instead.  Fix this using the correct metadata_uuid in the superblock
argument.

CC: stable@vger.kernel.org # 5.4+
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.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>
2023-08-21 14:54:48 +02:00
Anand Jain
d167aa76dc btrfs: use the correct superblock to compare fsid in btrfs_validate_super
The function btrfs_validate_super() should verify the fsid in the provided
superblock argument. Because, all its callers expect it to do that.

Such as in the following stack:

   write_all_supers()
       sb = fs_info->super_for_commit;
       btrfs_validate_write_super(.., sb)
         btrfs_validate_super(.., sb, ..)

   scrub_one_super()
	btrfs_validate_super(.., sb, ..)

And
   check_dev_super()
	btrfs_validate_super(.., sb, ..)

However, it currently verifies the fs_info::super_copy::fsid instead,
which is not correct.  Fix this using the correct fsid in the superblock
argument.

CC: stable@vger.kernel.org # 5.4+
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.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>
2023-08-21 14:54:48 +02:00
Ruan Jinjie
84af994b85 btrfs: use LIST_HEAD() to initialize the list_head
Use LIST_HEAD() to initialize the list_head instead of open-coding it.

Signed-off-by: Ruan Jinjie <ruanjinjie@huawei.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:54:46 +02:00
Naohiro Aota
a7e1ac7bdc btrfs: zoned: reserve zones for an active metadata/system block group
Ensure a metadata and system block group can be activated on write time, by
leaving a certain number of active zones when trying to activate a data
block group.

Zones for two metadata block groups (normal and tree-log) and one system
block group are reserved, according to the profile type: two zones per
block group on the DUP profile and one zone per block group otherwise.

The reservation must be freed once a non-data block group is allocated. If
not, we over-reserve the active zones and data block group activation will
suffer. For the dynamic reservation count, we need to manage the
reservation count per device.

The reservation count variable is protected by
fs_info->zone_active_bgs_lock.

Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:19 +02:00
Filipe Manana
504b1596bd btrfs: make btrfs_cleanup_fs_roots() static
btrfs_cleanup_fs_roots() is not used outside disk-io.c, so make it static,
remove its prototype from disk-io.h and move its definition above the
where it's used in disk-io.c

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:18 +02:00
Filipe Manana
ae3364e521 btrfs: store the error that turned the fs into error state
Currently when we turn the fs into an error state, typically after a
transaction abort, we don't store the error anywhere, we just set a bit
(BTRFS_FS_STATE_ERROR) at struct btrfs_fs_info::fs_state to signal the
error state.

There are cases where it would be useful to have access to the specific
error in order to provide a more meaningful error to users/applications.
This change adds a member to struct btrfs_fs_info to store the error and
removes the BTRFS_FS_STATE_ERROR bit. When there's no error, the new
member (fs_error) has a value of 0, otherwise its value is a negative
errno value.

Followup changes will make use of this new member.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:18 +02:00
Filipe Manana
e5860f8207 btrfs: make find_first_extent_bit() return a boolean
Currently find_first_extent_bit() returns a 0 if it found a range in the
given io tree and 1 if it didn't find any. There's no need to return any
errors, so make the return value a boolean and invert the logic to make
more sense: return true if it found a range and false if it didn't find
any range.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:12 +02:00
Filipe Manana
46d81ebd4a btrfs: make btrfs_destroy_pinned_extent() return void
Currently btrfs_destroy_pinned_extent() is always returning 0 no matter
what and its caller ignores its return value (as well everything up in
the call chain). This is because this is called in the transaction abort
path, where we can't even deal with any errors since we are in a critical
situation already and cleanup of resources is done in a best effort
fashion.

So make btrfs_destroy_pinned_extent() return void.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:12 +02:00
Filipe Manana
aec5716c3e btrfs: make btrfs_destroy_marked_extents() return void
Currently btrfs_destroy_marked_extents() is returning the value of the
last call to find_first_extent_bit(), which returns a value of 1 meaning
no more ranges found the dirty pages io tree. This value is useless to the
single caller of btrfs_destroy_marked_extents(), which ignores any return
value from btrfs_destroy_marked_extents(). This is because it's only used
in the transaction abort path, where we can't even deal with any errors
since we are in a critical situation already and cleanup of resources is
done in a best effort fashion.

So make btrfs_destroy_marked_extents() return void.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-21 14:52:12 +02:00
Qu Wenruo
6ebcd021c9 btrfs: reject invalid reloc tree root keys with stack dump
[BUG]
Syzbot reported a crash that an ASSERT() got triggered inside
prepare_to_merge().

That ASSERT() makes sure the reloc tree is properly pointed back by its
subvolume tree.

[CAUSE]
After more debugging output, it turns out we had an invalid reloc tree:

  BTRFS error (device loop1): reloc tree mismatch, root 8 has no reloc root, expect reloc root key (-8, 132, 8) gen 17

Note the above root key is (TREE_RELOC_OBJECTID, ROOT_ITEM,
QUOTA_TREE_OBJECTID), meaning it's a reloc tree for quota tree.

But reloc trees can only exist for subvolumes, as for non-subvolume
trees, we just COW the involved tree block, no need to create a reloc
tree since those tree blocks won't be shared with other trees.

Only subvolumes tree can share tree blocks with other trees (thus they
have BTRFS_ROOT_SHAREABLE flag).

Thus this new debug output proves my previous assumption that corrupted
on-disk data can trigger that ASSERT().

[FIX]
Besides the dedicated fix and the graceful exit, also let tree-checker to
check such root keys, to make sure reloc trees can only exist for subvolumes.

CC: stable@vger.kernel.org # 5.15+
Reported-by: syzbot+ae97a827ae1c3336bbb4@syzkaller.appspotmail.com
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-10 17:14:42 +02:00
Qu Wenruo
773e722a98 btrfs: avoid race between qgroup tree creation and relocation
[BUG]
Syzbot reported a weird ASSERT() triggered inside prepare_to_merge().

  assertion failed: root->reloc_root == reloc_root, in fs/btrfs/relocation.c:1919
  ------------[ cut here ]------------
  kernel BUG at fs/btrfs/relocation.c:1919!
  invalid opcode: 0000 [#1] PREEMPT SMP KASAN
  CPU: 0 PID: 9904 Comm: syz-executor.3 Not tainted
  6.4.0-syzkaller-08881-g533925cb7604 #0
  Hardware name: Google Google Compute Engine/Google Compute Engine,
  BIOS Google 05/27/2023
  RIP: 0010:prepare_to_merge+0xbb2/0xc40 fs/btrfs/relocation.c:1919
  Code: fe e9 f5 (...)
  RSP: 0018:ffffc9000325f760 EFLAGS: 00010246
  RAX: 000000000000004f RBX: ffff888075644030 RCX: 1481ccc522da5800
  RDX: ffffc90005c09000 RSI: 00000000000364ca RDI: 00000000000364cb
  RBP: ffffc9000325f870 R08: ffffffff816f33ac R09: 1ffff9200064bea0
  R10: dffffc0000000000 R11: fffff5200064bea1 R12: ffff888075644000
  R13: ffff88803b166000 R14: ffff88803b166560 R15: ffff88803b166558
  FS:  00007f4e305fd700(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 000056080679c000 CR3: 00000000193ad000 CR4: 00000000003506f0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  Call Trace:
   <TASK>
   relocate_block_group+0xa5d/0xcd0 fs/btrfs/relocation.c:3749
   btrfs_relocate_block_group+0x7ab/0xd70 fs/btrfs/relocation.c:4087
   btrfs_relocate_chunk+0x12c/0x3b0 fs/btrfs/volumes.c:3283
   __btrfs_balance+0x1b06/0x2690 fs/btrfs/volumes.c:4018
   btrfs_balance+0xbdb/0x1120 fs/btrfs/volumes.c:4402
   btrfs_ioctl_balance+0x496/0x7c0 fs/btrfs/ioctl.c:3604
   vfs_ioctl fs/ioctl.c:51 [inline]
   __do_sys_ioctl fs/ioctl.c:870 [inline]
   __se_sys_ioctl+0xf8/0x170 fs/ioctl.c:856
   do_syscall_x64 arch/x86/entry/common.c:50 [inline]
   do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
   entry_SYSCALL_64_after_hwframe+0x63/0xcd
  RIP: 0033:0x7f4e2f88c389

[CAUSE]
With extra debugging, the offending reloc_root is for quota tree (rootid 8).

Normally we should not use the reloc tree for quota root at all, as reloc
trees are only for subvolume trees.

But there is a race between quota enabling and relocation, this happens
after commit 85724171b3 ("btrfs: fix the btrfs_get_global_root return value").

Before that commit, for quota and free space tree, we exit immediately
if we cannot grab it from fs_info.

But now we would try to read it from disk, just as if they are fs trees,
this sets ROOT_SHAREABLE flags in such race:

             Thread A             |           Thread B
 ---------------------------------+------------------------------
 btrfs_quota_enable()             |
 |                                | btrfs_get_root_ref()
 |                                | |- btrfs_get_global_root()
 |                                | |  Returned NULL
 |                                | |- btrfs_lookup_fs_root()
 |                                | |  Returned NULL
 |- btrfs_create_tree()           | |
 |  Now quota root item is        | |
 |  inserted                      | |- btrfs_read_tree_root()
 |                                | |  Got the newly inserted quota root
 |                                | |- btrfs_init_fs_root()
 |                                | |  Set ROOT_SHAREABLE flag

[FIX]
Get back to the old behavior by returning PTR_ERR(-ENOENT) if the target
objectid is not a subvolume tree or data reloc tree.

Reported-and-tested-by: syzbot+ae97a827ae1c3336bbb4@syzkaller.appspotmail.com
Fixes: 85724171b3 ("btrfs: fix the btrfs_get_global_root return value")
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-08-10 17:10:10 +02:00
Naohiro Aota
95ca6599a5 btrfs: zoned: do not enable async discard
The zoned mode need to reset a zone before using it. We rely on btrfs's
original discard functionality (discarding unused block group range) to do
the resetting.

While the commit 63a7cb1307 ("btrfs: auto enable discard=async when
possible") made the discard done in an async manner, a zoned reset do not
need to be async, as it is fast enough.

Even worth, delaying zone rests prevents using those zones again. So, let's
disable async discard on the zoned mode.

Fixes: 63a7cb1307 ("btrfs: auto enable discard=async when possible")
CC: stable@vger.kernel.org # 6.3+
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update message text ]
Signed-off-by: David Sterba <dsterba@suse.com>
2023-07-20 19:18:14 +02:00
David Sterba
efcfcbc6a3 btrfs: add xxhash to fast checksum implementations
The implementation of XXHASH is now CPU only but still fast enough to be
considered for the synchronous checksumming, like non-generic crc32c.

A userspace benchmark comparing it to various implementations (patched
hash-speedtest from btrfs-progs):

  Block size:     4096
  Iterations:     1000000
  Implementation: builtin
  Units:          CPU cycles

	NULL-NOP: cycles:     73384294, cycles/i       73
     NULL-MEMCPY: cycles:    228033868, cycles/i      228,    61664.320 MiB/s
      CRC32C-ref: cycles:  24758559416, cycles/i    24758,      567.950 MiB/s
       CRC32C-NI: cycles:   1194350470, cycles/i     1194,    11773.433 MiB/s
  CRC32C-ADLERSW: cycles:   6150186216, cycles/i     6150,     2286.372 MiB/s
  CRC32C-ADLERHW: cycles:    626979180, cycles/i      626,    22427.453 MiB/s
      CRC32C-PCL: cycles:    466746732, cycles/i      466,    30126.699 MiB/s
	  XXHASH: cycles:    860656400, cycles/i      860,    16338.188 MiB/s

Comparing purely software implementation (ref), current outdated
accelerated using crc32q instruction (NI), optimized implementations by
M. Adler (https://stackoverflow.com/questions/17645167/implementing-sse-4-2s-crc32c-in-software/17646775#17646775)
and the best one that was taken from kernel using the PCLMULQDQ
instruction (PCL).

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19 13:59:33 +02:00
Filipe Manana
99f09ce309 btrfs: make btrfs_destroy_delayed_refs() return void
btrfs_destroy_delayed_refs() always returns 0 and its single caller does
not check its return value, as it also returns void, and so does the
callers' caller and so on. This is because we are in the transaction abort
path, where we have no way to deal with errors (we are in a critical
situation) and all cleanup of resources works in a best effort fashion.
So make btrfs_destroy_delayed_refs() return void.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19 13:59:32 +02:00
Filipe Manana
184533e361 btrfs: remove unnecessary prototype declarations at disk-io.c
We have a few static functions at disk-io.c for which we have a forward
declaration of their prototype, but it's not needed because all those
functions are defined before they are called, so remove them.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19 13:59:32 +02:00
Filipe Manana
4d34ad34d7 btrfs: remove pointless in_tree field from struct btrfs_delayed_ref_node
The 'in_tree' field is really not needed in struct btrfs_delayed_ref_node,
as we can check whether a reference is in the tree or not simply by
checking its red black tree node member with RB_EMPTY_NODE(), as when we
remove it from the tree we always call RB_CLEAR_NODE(). So remove that
field and use RB_EMPTY_NODE().

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19 13:59:31 +02:00
Tejun Heo
58e814fcac btrfs: use alloc_ordered_workqueue() to create ordered workqueues
BACKGROUND
==========

When multiple work items are queued to a workqueue, their execution order
doesn't match the queueing order. They may get executed in any order and
simultaneously. When fully serialized execution - one by one in the queueing
order - is needed, an ordered workqueue should be used which can be created
with alloc_ordered_workqueue().

However, alloc_ordered_workqueue() was a later addition. Before it, an
ordered workqueue could be obtained by creating an UNBOUND workqueue with
@max_active==1. This originally was an implementation side-effect which was
broken by 4c16bd327c ("workqueue: restore WQ_UNBOUND/max_active==1 to be
ordered"). Because there were users that depended on the ordered execution,
5c0338c687 ("workqueue: restore WQ_UNBOUND/max_active==1 to be ordered")
made workqueue allocation path to implicitly promote UNBOUND workqueues w/
@max_active==1 to ordered workqueues.

While this has worked okay, overloading the UNBOUND allocation interface
this way creates other issues. It's difficult to tell whether a given
workqueue actually needs to be ordered and users that legitimately want a
min concurrency level wq unexpectedly gets an ordered one instead. With
planned UNBOUND workqueue updates to improve execution locality and more
prevalence of chiplet designs which can benefit from such improvements, this
isn't a state we wanna be in forever.

This patch series audits all call sites that create an UNBOUND workqueue w/
@max_active==1 and converts them to alloc_ordered_workqueue() as necessary.

BTRFS
=====

* fs_info->scrub_workers initialized in scrub_workers_get() was setting
  @max_active to 1 when @is_dev_replace is set and it seems that the
  workqueue actually needs to be ordered if @is_dev_replace. Update the code
  so that alloc_ordered_workqueue() is used if @is_dev_replace.

* fs_info->discard_ctl.discard_workers initialized in
  btrfs_init_workqueues() was directly using alloc_workqueue() w/
  @max_active==1. Converted to alloc_ordered_workqueue().

* fs_info->fixup_workers and fs_info->qgroup_rescan_workers initialized in
  btrfs_queue_work() use the btrfs's workqueue wrapper, btrfs_workqueue,
  which are allocated with btrfs_alloc_workqueue().

  btrfs_workqueue implements automatic @max_active adjustment which is
  disabled when the specified max limit is below a certain threshold, so
  calling btrfs_alloc_workqueue() with @limit_active==1 yields an ordered
  workqueue whose @max_active won't be changed as the auto-tuning is
  disabled.

  This is rather brittle in that nothing clearly indicates that the two
  workqueues should be ordered or btrfs_alloc_workqueue() must disable
  auto-tuning when @limit_active==1.

  This patch factors out the common btrfs_workqueue init code into
  btrfs_init_workqueue() and add explicit btrfs_alloc_ordered_workqueue().
  The two workqueues are converted to use the new ordered allocation
  interface.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19 13:59:30 +02:00
Christoph Hellwig
25ac047c9d btrfs: remove a pointless NULL check in btrfs_lookup_fs_root
btrfs_grab_root already checks for a NULL root itself.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19 13:59:29 +02:00
Christoph Hellwig
e91909aace btrfs: convert btrfs_get_global_root to use a switch statement
Use a switch statement instead of an endless chain of if statements
to make the code a little cleaner.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19 13:59:29 +02:00
Christoph Hellwig
85724171b3 btrfs: fix the btrfs_get_global_root return value
btrfs_grab_root returns either the root or NULL, and the callers of
btrfs_get_global_root expect it to return the same.  But all the more
recently added roots instead return an ERR_PTR, so fix this.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19 13:59:29 +02:00
Anand Jain
25984a5ae8 btrfs: consolidate uuid comparisons in btrfs_validate_super
There are three ways the fsid is validated in btrfs_validate_super():

- verify that super_copy::fsid is the same as fs_devices::fsid

- if the metadata_uuid flag is set, verify if super_copy::metadata_uuid
  and fs_devices::metadata_uuid are the same.

- a few lines below, often missed out, verify if dev_item::fsid is the
  same as fs_devices::metadata_uuid.

The function btrfs_validate_super() contains multiple if-statements with
memcmp() to check UUIDs. This patch consolidates them into a single
location.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19 13:59:29 +02:00
Anand Jain
413fb1bc1d btrfs: return bool from check_tree_block_fsid instead of int
Simplify the return type of check_tree_block_fsid() from int (1 or 0) to
bool. Its only user is interested in knowing the success or failure.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19 13:59:29 +02:00
Christoph Hellwig
9e2aff90fc btrfs: stop using lock_extent in btrfs_buffer_uptodate
The only other place that locks extents on the btree inode is
read_extent_buffer_subpage while reading in the partial page for a
buffer.  This means locking the extent in btrfs_buffer_uptodate does not
synchronize with anything on non-subpage file systems, and on subpage
file systems it only waits for a parallel read(-ahead) to finish,
which seems to be counter to what the callers actually expect.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19 13:59:28 +02:00
Christoph Hellwig
31d89399da btrfs: remove the extent_buffer lookup in btree block checksumming
The checksumming of btree blocks always operates on the entire
extent_buffer, and because btree blocks are always allocated contiguously
on disk they are never split by btrfs_submit_bio.

Simplify the checksumming code by finding the extent_buffer in the
btrfs_bio private data instead of trying to search through the bio_vec.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19 13:59:28 +02:00
Christoph Hellwig
046b562b20 btrfs: use a separate end_io handler for read_extent_buffer
Now that we always use a single bio to read an extent_buffer, the buffer
can be passed to the end_io handler as private data.  This allows
implementing a much simplified dedicated end I/O handler for metadata
reads.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19 13:59:27 +02:00
Christoph Hellwig
d87e6575e9 btrfs: merge verify_parent_transid and btrfs_buffer_uptodate
verify_parent_transid is only called by btrfs_buffer_uptodate, which
confusingly inverts the return value.  Merge the two functions and
reflow the parent_transid so that error handling is in a branch.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19 13:59:27 +02:00
Christoph Hellwig
aebcc1596b btrfs: move setting the buffer uptodate out of validate_extent_buffer
Setting the buffer uptodate in a function that is named as a validation
helper is a it confusing.  Move the call from validate_extent_buffer to
the one of its two callers that didn't already have a duplicate call
to set_extent_buffer_uptodate.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19 13:59:27 +02:00
Christoph Hellwig
f880fe6e0b btrfs: don't hold an extra reference for redirtied buffers
When btrfs_redirty_list_add redirties a buffer, it also acquires
an extra reference that is released on transaction commit.  But
this is not required as buffers that are dirty or under writeback
are never freed (look for calls to extent_buffer_under_io())).

Remove the extra reference and the infrastructure used to drop it
again.

History behind redirty logic:

In the first place, it used releasing_list to hold all the
to-be-released extent buffers, and decided which buffers to re-dirty at
the commit time. Then, in a later version, the behaviour got changed to
re-dirty a necessary buffer and add re-dirtied one to the list in
btrfs_free_tree_block(). In short, the list was there mostly for the
patch series' historical reason.

Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
[ add Naohiro's comment regarding history ]
Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19 13:59:26 +02:00
Christoph Hellwig
f18cc97845 btrfs: fix dirty_metadata_bytes for redirtied buffers
dirty_metadata_bytes is decremented in both places that clear the dirty
bit in a buffer, but only incremented in btrfs_mark_buffer_dirty, which
means that a buffer that is redirtied using btrfs_redirty_list_add won't
be added to dirty_metadata_bytes, but it will be subtracted when written
out, leading an inconsistency in the counter.

Move the dirty_metadata_bytes from btrfs_mark_buffer_dirty into
set_extent_buffer_dirty to also account for the redirty case, and remove
the now unused set_extent_buffer_dirty return value.

Fixes: d3575156f6 ("btrfs: zoned: redirty released extent buffers")
CC: stable@vger.kernel.org # 5.15+
Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19 13:59:25 +02:00
Josef Bacik
2cac5af165 btrfs: move btrfs_verify_level_key into tree-checker.c
This is more a buffer validation helper, move it into the tree-checker
files where it makes more sense.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19 13:59:25 +02:00
Josef Bacik
85d8a826c7 btrfs: simplify btrfs_check_leaf_* helpers into a single helper
We have two helpers for checking leaves, because we have an extra check
for debugging in btrfs_mark_buffer_dirty(), and at that stage we may
have item data that isn't consistent yet.  However we can handle this
case internally in the helper, if BTRFS_HEADER_FLAG_WRITTEN is set we
know the buffer should be internally consistent, otherwise we need to
skip checking the item data.

Simplify this helper down a single helper and handle the item data
checking logic internally to the helper.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19 13:59:24 +02:00
Christoph Hellwig
8bfec2e426 btrfs: remove hipri_workers workqueue
Now that btrfs_wq_submit_bio is never called for synchronous I/O,
the hipri_workers workqueue is not used anymore and can be removed.

Reviewed-by: Chris Mason <clm@fb.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19 13:59:23 +02:00
Qu Wenruo
745806fb45 btrfs: do not ASSERT() on duplicated global roots
[BUG]
Syzbot reports a reproducible ASSERT() when using rescue=usebackuproot
mount option on a corrupted fs.

The full report can be found here:
https://syzkaller.appspot.com/bug?extid=c4614eae20a166c25bf0

  BTRFS error (device loop0: state C): failed to load root csum
  assertion failed: !tmp, in fs/btrfs/disk-io.c:1103
  ------------[ cut here ]------------
  kernel BUG at fs/btrfs/ctree.h:3664!
  invalid opcode: 0000 [#1] PREEMPT SMP KASAN
  CPU: 1 PID: 3608 Comm: syz-executor356 Not tainted 6.0.0-rc7-syzkaller-00029-g3800a713b607 #0
  Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022
  RIP: 0010:assertfail+0x1a/0x1c fs/btrfs/ctree.h:3663
  RSP: 0018:ffffc90003aaf250 EFLAGS: 00010246
  RAX: 0000000000000032 RBX: 0000000000000000 RCX: f21c13f886638400
  RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
  RBP: ffff888021c640a0 R08: ffffffff816bd38d R09: ffffed10173667f1
  R10: ffffed10173667f1 R11: 1ffff110173667f0 R12: dffffc0000000000
  R13: ffff8880229c21f7 R14: ffff888021c64060 R15: ffff8880226c0000
  FS:  0000555556a73300(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 000055a2637d7a00 CR3: 00000000709c4000 CR4: 00000000003506e0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  Call Trace:
   <TASK>
   btrfs_global_root_insert+0x1a7/0x1b0 fs/btrfs/disk-io.c:1103
   load_global_roots_objectid+0x482/0x8c0 fs/btrfs/disk-io.c:2467
   load_global_roots fs/btrfs/disk-io.c:2501 [inline]
   btrfs_read_roots fs/btrfs/disk-io.c:2528 [inline]
   init_tree_roots+0xccb/0x203c fs/btrfs/disk-io.c:2939
   open_ctree+0x1e53/0x33df fs/btrfs/disk-io.c:3574
   btrfs_fill_super+0x1c6/0x2d0 fs/btrfs/super.c:1456
   btrfs_mount_root+0x885/0x9a0 fs/btrfs/super.c:1824
   legacy_get_tree+0xea/0x180 fs/fs_context.c:610
   vfs_get_tree+0x88/0x270 fs/super.c:1530
   fc_mount fs/namespace.c:1043 [inline]
   vfs_kern_mount+0xc9/0x160 fs/namespace.c:1073
   btrfs_mount+0x3d3/0xbb0 fs/btrfs/super.c:1884

[CAUSE]
Since the introduction of global roots, we handle
csum/extent/free-space-tree roots as global roots, even if no
extent-tree-v2 feature is enabled.

So for regular csum/extent/fst roots, we load them into
fs_info::global_root_tree rb tree.

And we should not expect any conflicts in that rb tree, thus we have an
ASSERT() inside btrfs_global_root_insert().

But rescue=usebackuproot can break the assumption, as we will try to
load those trees again and again as long as we have bad roots and have
backup roots slot remaining.

So in that case we can have conflicting roots in the rb tree, and
triggering the ASSERT() crash.

[FIX]
We can safely remove that ASSERT(), as the caller will properly put the
offending root.

To make further debugging easier, also add two explicit error messages:

- Error message for conflicting global roots
- Error message when using backup roots slot

Reported-by: syzbot+a694851c6ab28cbcfb9c@syzkaller.appspotmail.com
Fixes: abed4aaae4 ("btrfs: track the csum, extent, and free space trees in a rb tree")
CC: stable@vger.kernel.org # 6.1+
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-13 01:21:16 +02:00
Qu Wenruo
917ac77846 btrfs: subpage: fix a crash in metadata repair path
[BUG]
Test case btrfs/027 would crash with subpage (64K page size, 4K
sectorsize) with the following dying messages:

  debug: map_length=16384 length=65536 type=metadata|raid6(0x104)
  assertion failed: map_length >= length, in fs/btrfs/volumes.c:8093
  ------------[ cut here ]------------
  kernel BUG at fs/btrfs/messages.c:259!
  Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015
  Call trace:
   btrfs_assertfail+0x28/0x2c [btrfs]
   btrfs_map_repair_block+0x150/0x2b8 [btrfs]
   btrfs_repair_io_failure+0xd4/0x31c [btrfs]
   btrfs_read_extent_buffer+0x150/0x16c [btrfs]
   read_tree_block+0x38/0xbc [btrfs]
   read_tree_root_path+0xfc/0x1bc [btrfs]
   btrfs_get_root_ref.part.0+0xd4/0x3a8 [btrfs]
   open_ctree+0xa30/0x172c [btrfs]
   btrfs_mount_root+0x3c4/0x4a4 [btrfs]
   legacy_get_tree+0x30/0x60
   vfs_get_tree+0x28/0xec
   vfs_kern_mount.part.0+0x90/0xd4
   vfs_kern_mount+0x14/0x28
   btrfs_mount+0x114/0x418 [btrfs]
   legacy_get_tree+0x30/0x60
   vfs_get_tree+0x28/0xec
   path_mount+0x3e0/0xb64
   __arm64_sys_mount+0x200/0x2d8
   invoke_syscall+0x48/0x114
   el0_svc_common.constprop.0+0x60/0x11c
   do_el0_svc+0x38/0x98
   el0_svc+0x40/0xa8
   el0t_64_sync_handler+0xf4/0x120
   el0t_64_sync+0x190/0x194
  Code: aa0403e2 b0fff060 91010000 959c2024 (d4210000)

[CAUSE]
In btrfs/027 we test RAID6 with missing devices, in this particular
case, we're repairing a metadata at the end of a data stripe.

But at btrfs_repair_io_failure(), we always pass a full PAGE for repair,
and for subpage case this can cross stripe boundary and lead to the
above BUG_ON().

This metadata repair code is always there, since the introduction of
subpage support, but this can trigger BUG_ON() after the bio split
ability at btrfs_map_bio().

[FIX]
Instead of passing the old PAGE_SIZE, we calculate the correct length
based on the eb size and page size for both regular and subpage cases.

CC: stable@vger.kernel.org # 6.3+
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-05 19:21:57 +02:00
pengfuyuan
5ad9b4719f btrfs: fix csum_tree_block page iteration to avoid tripping on -Werror=array-bounds
When compiling on a MIPS 64-bit machine we get these warnings:

    In file included from ./arch/mips/include/asm/cacheflush.h:13,
	             from ./include/linux/cacheflush.h:5,
	             from ./include/linux/highmem.h:8,
		     from ./include/linux/bvec.h:10,
		     from ./include/linux/blk_types.h:10,
                     from ./include/linux/blkdev.h:9,
	             from fs/btrfs/disk-io.c:7:
    fs/btrfs/disk-io.c: In function ‘csum_tree_block’:
    fs/btrfs/disk-io.c💯34: error: array subscript 1 is above array bounds of ‘struct page *[1]’ [-Werror=array-bounds]
      100 |   kaddr = page_address(buf->pages[i]);
          |                        ~~~~~~~~~~^~~
    ./include/linux/mm.h:2135:48: note: in definition of macro ‘page_address’
     2135 | #define page_address(page) lowmem_page_address(page)
          |                                                ^~~~
    cc1: all warnings being treated as errors

We can check if i overflows to solve the problem. However, this doesn't make
much sense, since i == 1 and num_pages == 1 doesn't execute the body of the loop.
In addition, i < num_pages can also ensure that buf->pages[i] will not cross
the boundary. Unfortunately, this doesn't help with the problem observed here:
gcc still complains.

To fix this add a compile-time condition for the extent buffer page
array size limit, which would eventually lead to eliminating the whole
for loop.

CC: stable@vger.kernel.org # 5.10+
Signed-off-by: pengfuyuan <pengfuyuan@kylinos.cn>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-05-26 23:24:55 +02:00
Josef Bacik
597441b343 btrfs: use nofs when cleaning up aborted transactions
Our CI system caught a lockdep splat:

  ======================================================
  WARNING: possible circular locking dependency detected
  6.3.0-rc7+ #1167 Not tainted
  ------------------------------------------------------
  kswapd0/46 is trying to acquire lock:
  ffff8c6543abd650 (sb_internal#2){++++}-{0:0}, at: btrfs_commit_inode_delayed_inode+0x5f/0x120

  but task is already holding lock:
  ffffffffabe61b40 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0x4aa/0x7a0

  which lock already depends on the new lock.

  the existing dependency chain (in reverse order) is:

  -> #1 (fs_reclaim){+.+.}-{0:0}:
	 fs_reclaim_acquire+0xa5/0xe0
	 kmem_cache_alloc+0x31/0x2c0
	 alloc_extent_state+0x1d/0xd0
	 __clear_extent_bit+0x2e0/0x4f0
	 try_release_extent_mapping+0x216/0x280
	 btrfs_release_folio+0x2e/0x90
	 invalidate_inode_pages2_range+0x397/0x470
	 btrfs_cleanup_dirty_bgs+0x9e/0x210
	 btrfs_cleanup_one_transaction+0x22/0x760
	 btrfs_commit_transaction+0x3b7/0x13a0
	 create_subvol+0x59b/0x970
	 btrfs_mksubvol+0x435/0x4f0
	 __btrfs_ioctl_snap_create+0x11e/0x1b0
	 btrfs_ioctl_snap_create_v2+0xbf/0x140
	 btrfs_ioctl+0xa45/0x28f0
	 __x64_sys_ioctl+0x88/0xc0
	 do_syscall_64+0x38/0x90
	 entry_SYSCALL_64_after_hwframe+0x72/0xdc

  -> #0 (sb_internal#2){++++}-{0:0}:
	 __lock_acquire+0x1435/0x21a0
	 lock_acquire+0xc2/0x2b0
	 start_transaction+0x401/0x730
	 btrfs_commit_inode_delayed_inode+0x5f/0x120
	 btrfs_evict_inode+0x292/0x3d0
	 evict+0xcc/0x1d0
	 inode_lru_isolate+0x14d/0x1e0
	 __list_lru_walk_one+0xbe/0x1c0
	 list_lru_walk_one+0x58/0x80
	 prune_icache_sb+0x39/0x60
	 super_cache_scan+0x161/0x1f0
	 do_shrink_slab+0x163/0x340
	 shrink_slab+0x1d3/0x290
	 shrink_node+0x300/0x720
	 balance_pgdat+0x35c/0x7a0
	 kswapd+0x205/0x410
	 kthread+0xf0/0x120
	 ret_from_fork+0x29/0x50

  other info that might help us debug this:

   Possible unsafe locking scenario:

	 CPU0                    CPU1
	 ----                    ----
    lock(fs_reclaim);
				 lock(sb_internal#2);
				 lock(fs_reclaim);
    lock(sb_internal#2);

   *** DEADLOCK ***

  3 locks held by kswapd0/46:
   #0: ffffffffabe61b40 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0x4aa/0x7a0
   #1: ffffffffabe50270 (shrinker_rwsem){++++}-{3:3}, at: shrink_slab+0x113/0x290
   #2: ffff8c6543abd0e0 (&type->s_umount_key#44){++++}-{3:3}, at: super_cache_scan+0x38/0x1f0

  stack backtrace:
  CPU: 0 PID: 46 Comm: kswapd0 Not tainted 6.3.0-rc7+ #1167
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-2.fc32 04/01/2014
  Call Trace:
   <TASK>
   dump_stack_lvl+0x58/0x90
   check_noncircular+0xd6/0x100
   ? save_trace+0x3f/0x310
   ? add_lock_to_list+0x97/0x120
   __lock_acquire+0x1435/0x21a0
   lock_acquire+0xc2/0x2b0
   ? btrfs_commit_inode_delayed_inode+0x5f/0x120
   start_transaction+0x401/0x730
   ? btrfs_commit_inode_delayed_inode+0x5f/0x120
   btrfs_commit_inode_delayed_inode+0x5f/0x120
   btrfs_evict_inode+0x292/0x3d0
   ? lock_release+0x134/0x270
   ? __pfx_wake_bit_function+0x10/0x10
   evict+0xcc/0x1d0
   inode_lru_isolate+0x14d/0x1e0
   __list_lru_walk_one+0xbe/0x1c0
   ? __pfx_inode_lru_isolate+0x10/0x10
   ? __pfx_inode_lru_isolate+0x10/0x10
   list_lru_walk_one+0x58/0x80
   prune_icache_sb+0x39/0x60
   super_cache_scan+0x161/0x1f0
   do_shrink_slab+0x163/0x340
   shrink_slab+0x1d3/0x290
   shrink_node+0x300/0x720
   balance_pgdat+0x35c/0x7a0
   kswapd+0x205/0x410
   ? __pfx_autoremove_wake_function+0x10/0x10
   ? __pfx_kswapd+0x10/0x10
   kthread+0xf0/0x120
   ? __pfx_kthread+0x10/0x10
   ret_from_fork+0x29/0x50
   </TASK>

This happens because when we abort the transaction in the transaction
commit path we call invalidate_inode_pages2_range on our block group
cache inodes (if we have space cache v1) and any delalloc inodes we may
have.  The plain invalidate_inode_pages2_range() call passes through
GFP_KERNEL, which makes sense in most cases, but not here.  Wrap these
two invalidate callees with memalloc_nofs_save/memalloc_nofs_restore to
make sure we don't end up with the fs reclaim dependency under the
transaction dependency.

CC: stable@vger.kernel.org # 4.14+
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-05-17 13:08:28 +02:00
Qu Wenruo
1d6a4fc857 btrfs: make clear_cache mount option to rebuild FST without disabling it
Previously clear_cache mount option would simply disable free-space-tree
feature temporarily then re-enable it to rebuild the whole free space
tree.

But this is problematic for block-group-tree feature, as we have an
artificial dependency on free-space-tree feature.

If we go the existing method, after clearing the free-space-tree
feature, we would flip the filesystem to read-only mode, as we detect a
super block write with block-group-tree but no free-space-tree feature.

This patch would change the behavior by properly rebuilding the free
space tree without disabling this feature, thus allowing clear_cache
mount option to work with block group tree.

Now we can mount a filesystem with block-group-tree feature and
clear_mount option:

  $ mkfs.btrfs  -O block-group-tree /dev/test/scratch1  -f
  $ sudo mount /dev/test/scratch1 /mnt/btrfs -o clear_cache
  $ sudo dmesg -t | head -n 5
  BTRFS info (device dm-1): force clearing of disk cache
  BTRFS info (device dm-1): using free space tree
  BTRFS info (device dm-1): auto enabling async discard
  BTRFS info (device dm-1): rebuilding free space tree
  BTRFS info (device dm-1): checking UUID tree

CC: stable@vger.kernel.org # 6.1+
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-05-10 14:51:27 +02:00
Anand Jain
7e812f2054 btrfs: use test_and_clear_bit() in wait_dev_flush()
The function wait_dev_flush() tests for the BTRFS_DEV_STATE_FLUSH_SENT
bit and then clears it separately. Instead, use test_and_clear_bit().
Though we don't need to do the atomic test and clear, it's following a
common pattern.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-04-17 18:01:20 +02:00
Anand Jain
1b465784dc btrfs: change wait_dev_flush() return type to bool
The flush error code is maintained in btrfs_device::last_flush_error, so
there is no point in returning it in wait_dev_flush() when it is not being
used. Instead, we can return a boolean value.

Note that even though btrfs_device::last_flush_error may not be used, we
will keep it for now.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-04-17 18:01:20 +02:00
Anand Jain
de38a206ff btrfs: open code check_barrier_error()
check_barrier_error() is almost a single line function, and just calls
btrfs_check_rw_degradable(). Instead, open code it.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-04-17 18:01:20 +02:00
Anand Jain
bfd3ea946f btrfs: move last_flush_error to write_dev_flush and wait_dev_flush
We parallelize the flush command across devices using our own code,
write_dev_flush() sends the flush command to each device and
wait_dev_flush() waits for the flush to complete on all devices. Errors
from each device are recorded at device->last_flush_error and reset to
BLK_STS_OK in write_dev_flush() and to the error, if any, in
wait_dev_flush(). These functions are called from barrier_all_devices().

This patch consolidates the use of device->last_flush_error in
write_dev_flush() and wait_dev_flush() to remove it from
barrier_all_devices().

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-04-17 18:01:20 +02:00
Filipe Manana
a8fdc05172 btrfs: remove obsolete delayed ref throttling logic when truncating items
We have this logic encapsulated in btrfs_should_throttle_delayed_refs()
where we try to estimate if running the current amount of delayed
references we have will take more than half a second, and if so, the
caller btrfs_should_throttle_delayed_refs() should do something to
prevent more and more delayed refs from being accumulated.

This logic was added in commit 0a2b2a844a ("Btrfs: throttle delayed
refs better") and then further refined in commit a79b7d4b3e ("Btrfs:
async delayed refs"). The idea back then was that the caller of
btrfs_should_throttle_delayed_refs() would release its transaction
handle (by calling btrfs_end_transaction()) when that function returned
true, then btrfs_end_transaction() would trigger an async job to run
delayed references in a workqueue, and later start/join a transaction
again and do more work.

However we don't run delayed references asynchronously anymore, that
was removed in commit db2462a6ad ("btrfs: don't run delayed refs in
the end transaction logic"). That makes the logic that tries to estimate
how long we will take to run our current delayed references, at
btrfs_should_throttle_delayed_refs(), pointless as we don't take any
action to run delayed references anymore. We do have other type of
throttling, which consists of checking the size and reserved space of
the delayed and global block reserves, as well as if fluhsing delayed
references for the current transaction was already started, etc - this
is all done by btrfs_should_end_transaction(), and the only user of
btrfs_should_throttle_delayed_refs() does periodically call
btrfs_should_end_transaction().

So remove btrfs_should_throttle_delayed_refs() and the infrastructure
that keeps track of the average time used for running delayed references,
as well as adapting btrfs_truncate_inode_items() to call
btrfs_check_space_for_delayed_refs() instead.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-04-17 18:01:19 +02:00
David Sterba
0b5485391d btrfs: locking: use atomic for DREW lock writers
The DREW lock uses percpu variable to track lock counters and for that
it needs to allocate the structure. In btrfs_read_tree_root() or
btrfs_init_fs_root() this may add another error case or requires the
NOFS scope protection.

One way is to preallocate the structure as was suggested in
https://lore.kernel.org/linux-btrfs/20221214021125.28289-1-robbieko@synology.com/

We may avoid the allocation altogether if we don't use the percpu
variables but an atomic for the writer counter. This should not make any
difference, the DREW lock is used for truncate and NOCOW writes along
with other IO operations.

The percpu counter for writers has been there since the original commit
8257b2dc3c "Btrfs: introduce btrfs_{start, end}_nocow_write() for
each subvolume". The reason could be to avoid hammering the same
cacheline from all the readers but then the writers do that anyway.

Signed-off-by: David Sterba <dsterba@suse.com>
2023-04-17 18:01:17 +02:00
Anand Jain
ce4cf3793e btrfs: remove redundant clearing of NODISCARD
If no discard mount option is specified, including the NODISCARD option,
we make the async discard the default option then we don't have to call
the clear_opt again to clear the NODISCARD flag. Though this makes no
difference, that the call is redundant has been pointed out several
times so we better remove it.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-04-17 18:01:17 +02:00
Qu Wenruo
4871c33baf btrfs: open_ctree() error handling cleanup
Currently open_ctree() still uses two variables for error handling, err
and ret. This can be confusing and missing some errors and does not
conform to current coding style.

This patch will fix the problems by:

- Use only ret for error handling

- Add proper ret assignment
  Originally we rely on the default value (-EINVAL) of err to handle
  errors, but that doesn't really reflects the error.
  This will change it use the correct error number for the following
  call sites:

  * subpage_info allocation
  * btrfs_free_extra_devids()
  * btrfs_check_rw_degradable()
  * cleaner_kthread allocation
  * transaction_kthread allocation

- Add an extra ASSERT()
  To make sure we error out instead of returning 0.

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>
2023-04-17 18:01:16 +02:00
Christoph Hellwig
dcb2137c84 btrfs: move all btree inode initialization into btrfs_init_btree_inode
Move the remaining code that deals with initializing the btree
inode into btrfs_init_btree_inode instead of splitting it between
that helpers and its only caller.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-04-17 18:01:13 +02:00
Josef Bacik
6989627db0 btrfs: drop root refs properly when orphan cleanup fails
When we mount the file system we do something like this:

	while (1) {
		lookup fs roots;

		for (i = 0; i < num_roots; i++) {
			ret = btrfs_orphan_cleanup(roots[i]);
			if (ret)
				break;
			btrfs_put_root(roots[i]);
		}
	}

	for (; i < num_roots; i++)
		btrfs_put_root(roots[i]);

As you can see if we break in that inner loop we just go back to the
outer loop and lose the fact that we have to drop references on the
remaining roots we looked up.  Fix this by making an out label and
jumping to that on error so we don't leak a reference to the roots we
looked up.

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>
2023-04-17 18:01:13 +02:00
Christoph Hellwig
68d99ab0e9 btrfs: fix fast csum implementation detection
The BTRFS_FS_CSUM_IMPL_FAST flag is currently set whenever a non-generic
crc32c is detected, which is the incorrect check if the file system uses
a different checksumming algorithm.  Refactor the code to only check
this if crc32c is actually used.  Note that in an ideal world the
information if an algorithm is hardware accelerated or not should be
provided by the crypto API instead, but that's left for another day.

CC: stable@vger.kernel.org # 5.4.x: c8a5f8ca9a9c: btrfs: print checksum type and implementation at mount time
CC: stable@vger.kernel.org # 5.4.x
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-04-06 16:34:13 +02:00
Josef Bacik
98c8d683c2 btrfs: combine btrfs_clear_buffer_dirty and clear_extent_buffer_dirty
btrfs_clear_buffer_dirty just does the test_clear_bit() and then calls
clear_extent_buffer_dirty and does the dirty metadata accounting.
Combine this into clear_extent_buffer_dirty and make the result
btrfs_clear_buffer_dirty.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-02-15 19:38:54 +01:00
Josef Bacik
190a83391b btrfs: rename btrfs_clean_tree_block to btrfs_clear_buffer_dirty
btrfs_clean_tree_block is a misnomer, it's just
clear_extent_buffer_dirty with some extra accounting around it.  Rename
this to btrfs_clear_buffer_dirty to make it more clear it belongs with
it's setter, btrfs_mark_buffer_dirty.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-02-15 19:38:53 +01:00
Josef Bacik
c4e54a6571 btrfs: replace clearing extent buffer dirty bit with btrfs_clean_block
Now that we're passing in the trans into btrfs_clean_tree_block, we can
easily roll in the handling of the !trans case and replace all
occurrences of

	if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &eb->bflags))
		clear_extent_buffer_dirty(eb);

with

	btrfs_tree_lock(eb);
	btrfs_clean_tree_block(eb);
	btrfs_tree_unlock(eb);

We need the lock because if we are actually dirty we need to make sure
we aren't racing with anything that's starting writeout currently.  This
also makes sure that we're accounting fs_info->dirty_metadata_bytes
appropriately.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-02-15 19:38:53 +01:00
Josef Bacik
ed25dab3a0 btrfs: add trans argument to btrfs_clean_tree_block
We check the header generation in the extent buffer against the current
running transaction id to see if it's safe to clear DIRTY on this
buffer.  Generally speaking if we're clearing the buffer dirty we're
holding the transaction open, but in the case of cleaning up an aborted
transaction we don't, so we have extra checks in that path to check the
transid.  To allow for a future cleanup go ahead and pass in the trans
handle so we don't have to rely on ->running_transaction being set.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-02-15 19:38:53 +01:00
Christoph Hellwig
35a8d7da3c btrfs: remove now spurious bio submission helpers
Call btrfs_submit_bio and btrfs_submit_compressed_read directly from
submit_one_bio now that all additional functionality has moved into
btrfs_submit_bio.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-02-15 19:38:53 +01:00
Christoph Hellwig
285599b6fe btrfs: remove the fs_info argument to btrfs_submit_bio
btrfs_submit_bio can derive it trivially from bbio->inode, so stop
bothering in the callers.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-02-15 19:38:53 +01:00
Christoph Hellwig
542e300e83 btrfs: support cloned bios in btree_csum_one_bio
To allow splitting bios in btrfs_submit_bio, btree_csum_one_bio needs to
be able to handle cloned bios.  As btree_csum_one_bio is always called
before handing the bio to the block layer that is trivially done by using
bio_for_each_segment instead of bio_for_each_segment_all.  Also switch
the function to take a btrfs_bio and use that to derive the fs_info.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-02-15 19:38:52 +01:00
Christoph Hellwig
f8a53bb58e btrfs: handle checksum generation in the storage layer
Instead of letting the callers of btrfs_submit_bio deal with checksumming
the (meta)data in the bio and making decisions on when to offload the
checksumming to the bio, leave that to btrfs_submit_bio.  Do do so the
existing btrfs_submit_bio function is split into an upper and a lower
half, so that the lower half can be offloaded to a workqueue.

Note that this changes the behavior for direct writes to raid56 volumes so
that async checksum offloading is not skipped when more I/O is expected.
This runs counter to the argument explaining why it was done, although I
can't measure any affects of the change.  Commits later in this series
will make sure the entire direct writes is offloaded to the workqueue
at once and thus make sure it is sent to the raid56 code from a single
thread.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-02-15 19:38:52 +01:00
Christoph Hellwig
f8c44673e5 btrfs: simplify the btrfs_csum_one_bio calling convention
To prepare for further bio submission changes btrfs_csum_one_bio
should be able to take all it's arguments from the btrfs_bio structure.
It can always use the bbio->inode already, and once the compression code
is updated to set ->file_offset that one can be used unconditionally
as well instead of looking at the page mapping now that btrfs doesn't
allow ordered extents to span discontiguous data ranges.

The only slightly tricky bit is the one_ordered flag set by the
compressed writes.  Replace that one with the driver private bio
flag, which gets cleared before the bio is handed off to the block layer
so that we don't get in the way of driver use.

Note: this leaves an argument and a flag to btrfs_wq_submit_bio unused.
But that whole mechanism will be removed in its current form in the
next patch.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-02-15 19:38:52 +01:00
Christoph Hellwig
deb6216fa0 btrfs: open code the submit_bio_start helpers
The submit helpers are now trivial and can be called directly.  Note
that btree_csum_one_bio has to be moved up in the file a bit to avoid a
forward declaration.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-02-15 19:38:52 +01:00
Christoph Hellwig
295fe46ff1 btrfs: remove struct btrfs_bio::is_metadata flag
This flag is unused now, so remove it.  Re-expand the mirror_num field
to 8 bits, and move it to the I/O completion internal section of the
structure.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-02-15 19:38:52 +01:00
Colin Ian King
67da05b3f2 btrfs: fix spelling mistakes found using codespell
There quite a few spelling mistakes as found using codespell. Fix them.

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-02-15 19:38:50 +01:00
Qu Wenruo
b7625f461d btrfs: sysfs: update fs features directory asynchronously
[BUG]
Since the introduction of per-fs feature sysfs interface
(/sys/fs/btrfs/<UUID>/features/), the content of that directory is never
updated.

Thus for the following case, that directory will not show the new
features like RAID56:

  # mkfs.btrfs -f $dev1 $dev2 $dev3
  # mount $dev1 $mnt
  # btrfs balance start -f -mconvert=raid5 $mnt
  # ls /sys/fs/btrfs/$uuid/features/
  extended_iref  free_space_tree  no_holes  skinny_metadata

While after unmount and mount, we got the correct features:

  # umount $mnt
  # mount $dev1 $mnt
  # ls /sys/fs/btrfs/$uuid/features/
  extended_iref  free_space_tree  no_holes  raid56 skinny_metadata

[CAUSE]
Because we never really try to update the content of per-fs features/
directory.

We had an attempt to update the features directory dynamically in commit
14e46e0495 ("btrfs: synchronize incompat feature bits with sysfs
files"), but unfortunately it get reverted in commit e410e34fad
("Revert "btrfs: synchronize incompat feature bits with sysfs files"").
The problem in the original patch is, in the context of
btrfs_create_chunk(), we can not afford to update the sysfs group.

The exported but never utilized function, btrfs_sysfs_feature_update()
is the leftover of such attempt.  As even if we go sysfs_update_group(),
new files will need extra memory allocation, and we have no way to
specify the sysfs update to go GFP_NOFS.

[FIX]
This patch will address the old problem by doing asynchronous sysfs
update in the cleaner thread.

This involves the following changes:

- Make __btrfs_(set|clear)_fs_(incompat|compat_ro) helpers to set
  BTRFS_FS_FEATURE_CHANGED flag when needed

- Update btrfs_sysfs_feature_update() to use sysfs_update_group()
  And drop unnecessary arguments.

- Call btrfs_sysfs_feature_update() in cleaner_kthread
  If we have the BTRFS_FS_FEATURE_CHANGED flag set.

- Wake up cleaner_kthread in btrfs_commit_transaction if we have
  BTRFS_FS_FEATURE_CHANGED flag

By this, all the previously dangerous call sites like
btrfs_create_chunk() need no new changes, as above helpers would
have already set the BTRFS_FS_FEATURE_CHANGED flag.

The real work happens at cleaner_kthread, thus we pay the cost of
delaying the update to sysfs directory, but the delayed time should be
small enough that end user can not distinguish though it might get
delayed if the cleaner thread is busy with removing subvolumes or
defrag.

CC: stable@vger.kernel.org # 4.14+
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>
2023-02-13 17:50:35 +01:00
Josef Bacik
a6ca692ec2 btrfs: fix uninitialized variable warning in run_one_async_start
With -Wmaybe-uninitialized compiler complains about ret being possibly
uninitialized, which isn't possible as the WQ_ constants are set only
from our code, however we can handle the default case and get rid of the
warning.

The value is set to BLK_STS_IOERR so it does not issue any IO and could
be potentially detected, but this is basically a "cannot happen" error.
To catch any problems during development use the assert.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ set the error in default: ]
Signed-off-by: David Sterba <dsterba@suse.com>
2023-02-13 17:50:33 +01:00
Filipe Manana
16199ad9eb btrfs: do not abort transaction on failure to write log tree when syncing log
When syncing the log, if we fail to write log tree extent buffers, we mark
the log for a full commit and abort the transaction. However we don't need
to abort the transaction, all we really need to do is to make sure no one
can commit a superblock pointing to new log tree roots. Just because we
got a failure writing extent buffers for a log tree, it does not mean we
will also fail to do a transaction commit.

One particular case is if due to a bug somewhere, when writing log tree
extent buffers, the tree checker detects some corruption and the writeout
fails because of that. Aborting the transaction can be very disruptive for
a user, specially if the issue happened on a root filesystem. One example
is the scenario in the Link tag below, where an isolated corruption on log
tree leaves was causing transaction aborts when syncing the log.

Link: https://lore.kernel.org/linux-btrfs/ae169fc6-f504-28f0-a098-6fa6a4dfb612@leemhuis.info/
CC: stable@vger.kernel.org # 5.15+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-01-12 15:43:30 +01:00
Qu Wenruo
2ba48b2004 btrfs: fix compat_ro checks against remount
[BUG]
Even with commit 81d5d61454 ("btrfs: enhance unsupported compat RO
flags handling"), btrfs can still mount a fs with unsupported compat_ro
flags read-only, then remount it RW:

  # btrfs ins dump-super /dev/loop0 | grep compat_ro_flags -A 3
  compat_ro_flags		0x403
			( FREE_SPACE_TREE |
			  FREE_SPACE_TREE_VALID |
			  unknown flag: 0x400 )

  # mount /dev/loop0 /mnt/btrfs
  mount: /mnt/btrfs: wrong fs type, bad option, bad superblock on /dev/loop0, missing codepage or helper program, or other error.
         dmesg(1) may have more information after failed mount system call.
  ^^^ RW mount failed as expected ^^^

  # dmesg -t | tail -n5
  loop0: detected capacity change from 0 to 1048576
  BTRFS: device fsid cb5b82f5-0fdd-4d81-9b4b-78533c324afa devid 1 transid 7 /dev/loop0 scanned by mount (1146)
  BTRFS info (device loop0): using crc32c (crc32c-intel) checksum algorithm
  BTRFS info (device loop0): using free space tree
  BTRFS error (device loop0): cannot mount read-write because of unknown compat_ro features (0x403)
  BTRFS error (device loop0): open_ctree failed

  # mount /dev/loop0 -o ro /mnt/btrfs
  # mount -o remount,rw /mnt/btrfs
  ^^^ RW remount succeeded unexpectedly ^^^

[CAUSE]
Currently we use btrfs_check_features() to check compat_ro flags against
our current mount flags.

That function get reused between open_ctree() and btrfs_remount().

But for btrfs_remount(), the super block we passed in still has the old
mount flags, thus btrfs_check_features() still believes we're mounting
read-only.

[FIX]
Replace the existing @sb argument with @is_rw_mount.

As originally we only use @sb to determine if the mount is RW.

Now it's callers' responsibility to determine if the mount is RW, and
since there are only two callers, the check is pretty simple:

- caller in open_ctree()
  Just pass !sb_rdonly().

- caller in btrfs_remount()
  Pass !(*flags & SB_RDONLY), as our check should be against the new
  flags.

Now we can correctly reject the RW remount:

  # mount /dev/loop0 -o ro /mnt/btrfs
  # mount -o remount,rw /mnt/btrfs
  mount: /mnt/btrfs: mount point not mounted or bad option.
         dmesg(1) may have more information after failed mount system call.
  # dmesg -t | tail -n 1
  BTRFS error (device loop0: state M): cannot mount read-write because of unknown compat_ro features (0x403)

Reported-by: Chung-Chiang Cheng <shepjeng@gmail.com>
Fixes: 81d5d61454 ("btrfs: enhance unsupported compat RO flags handling")
CC: stable@vger.kernel.org # 5.15+
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>
2023-01-03 16:22:13 +01:00
Qu Wenruo
77177ed17d btrfs: add error message for metadata level mismatch
From a recent regression report, we found that after commit 947a629988
("btrfs: move tree block parentness check into
validate_extent_buffer()") if we have a level mismatch (false alert
though), there is no error message at all.

This makes later debugging harder.  This patch will add the proper error
message for such case.

Link: https://lore.kernel.org/linux-btrfs/CABXGCsNzVxo4iq-tJSGm_kO1UggHXgq6CdcHDL=z5FL4njYXSQ@mail.gmail.com/
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-01-03 15:53:18 +01:00
Christoph Hellwig
bacf60e515 btrfs: move repair_io_failure to bio.c
repair_io_failure ties directly into all the glory low-level details of
mapping a bio with a logic address to the actual physical location.
Move it right below btrfs_submit_bio to keep all the related logic
together.

Also move btrfs_repair_eb_io_failure to its caller in disk-io.c now that
repair_io_failure is available in a header.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-12-05 18:00:57 +01:00
Christoph Hellwig
103c19723c btrfs: split the bio submission path into a separate file
The code used by btrfs_submit_bio only interacts with the rest of
volumes.c through __btrfs_map_block (which itself is a more generic
version of two exported helpers) and does not really have anything
to do with volumes.c.  Create a new bio.c file and a bio.h header
going along with it for the btrfs_bio-based storage layer, which
will grow even more going forward.

Also update the file with my copyright notice given that a large
part of the moved code was written or rewritten by me.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-12-05 18:00:57 +01:00
Qu Wenruo
cb3e217bdb btrfs: use btrfs_dev_name() helper to handle missing devices better
[BUG]
If dev-replace failed to re-construct its data/metadata, the kernel
message would be incorrect for the missing device:

 BTRFS info (device dm-1): dev_replace from <missing disk> (devid 2) to /dev/mapper/test-scratch2 started
 BTRFS error (device dm-1): failed to rebuild valid logical 38862848 for dev (efault)

Note the above "dev (efault)" of the second line.
While the first line is properly reporting "<missing disk>".

[CAUSE]
Although dev-replace is using btrfs_dev_name(), the heavy lifting work
is still done by scrub (scrub is reused by both dev-replace and regular
scrub).

Unfortunately scrub code never uses btrfs_dev_name() helper, as it's
only declared locally inside dev-replace.c.

[FIX]
Fix the output by:

- Move the btrfs_dev_name() helper to volumes.h

- Use btrfs_dev_name() to replace open-coded rcu_str_deref() calls
  Only zoned code is not touched, as I'm not familiar with degraded
  zoned code.

- Constify return value and parameter

Now the output looks pretty sane:

 BTRFS info (device dm-1): dev_replace from <missing disk> (devid 2) to /dev/mapper/test-scratch2 started
 BTRFS error (device dm-1): failed to rebuild valid logical 38862848 for dev <missing disk>

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-12-05 18:00:57 +01:00
Qu Wenruo
947a629988 btrfs: move tree block parentness check into validate_extent_buffer()
[BACKGROUND]
Although both btrfs metadata and data has their read time verification
done at endio time (btrfs_validate_metadata_buffer() and
btrfs_verify_data_csum()), metadata has extra verification, mostly
parentness check including first key/transid/owner_root/level, done at
read_tree_block() and btrfs_read_extent_buffer().

On the other hand, all the data verification is done at endio context.

[ENHANCEMENT]
This patch will make a new union in btrfs_bio, taking the space of the
old data checksums, thus it will not increase the memory usage.

With that extra btrfs_tree_parent_check inside btrfs_bio, we can just
pass the check parameter into read_extent_buffer_pages(), and before
submitting the bio, we can copy the check structure into btrfs_bio.

And finally at endio time, we can grab btrfs_bio::parent_check and pass
it to validate_extent_buffer(), to move the remaining checks into it.

This brings the following benefits:

- Much simpler btrfs_read_extent_buffer()
  Now it only needs to iterate through all mirrors.

- Simpler read-time transid check
  Previously we go verify_parent_transid() after reading out the extent
  buffer.
  Now the transid check is done inside the endio function, no other
  code can modify the content.
  Thus no need to use the extent lock anymore.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-12-05 18:00:56 +01:00
Qu Wenruo
789d6a3a87 btrfs: concentrate all tree block parentness check parameters into one structure
There are several different tree block parentness check parameters used
across several helpers:

- level
  Mandatory

- transid
  Under most cases it's mandatory, but there are several backref cases
  which skips this check.

- owner_root
- first_key
  Utilized by most top-down tree search routine. Otherwise can be
  skipped.

Those four members are not always mandatory checks, and some of them are
the same u64, which means if some arguments got swapped compiler will
not catch it.

Furthermore if we're going to further expand the parentness check, we
need to modify quite some helpers just to add one more parameter.

This patch will concentrate all these members into a structure called
btrfs_tree_parent_check, and pass that structure for the following
helpers:

- btrfs_read_extent_buffer()
- read_tree_block()

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-12-05 18:00:56 +01:00
David Sterba
35da5a7ede btrfs: drop private_data parameter from extent_io_tree_init
All callers except one pass NULL, so the parameter can be dropped and
the inode::io_tree initialization can be open coded.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-12-05 18:00:54 +01:00
David Sterba
644094fd28 btrfs: pass btrfs_inode to btrfs_submit_metadata_bio
The function is for internal interfaces so we should use the
btrfs_inode.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-12-05 18:00:52 +01:00
David Sterba
5fcdadc270 btrfs: pass btrfs_inode to btrfs_wq_submit_bio
The function is for internal interfaces so we should use the
btrfs_inode.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-12-05 18:00:52 +01:00
David Sterba
bfa1706682 btrfs: pass btrfs_inode to btrfs_submit_bio_start_direct_io
The function is for internal interfaces so we should use the
btrfs_inode.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-12-05 18:00:52 +01:00
David Sterba
882681ac98 btrfs: pass btrfs_inode to btrfs_submit_bio_start
The function is for internal interfaces so we should use the
btrfs_inode.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-12-05 18:00:52 +01:00
David Sterba
da67daab8d btrfs: switch async_submit_bio::inode to btrfs_inode
The async bio submit is for internal interfaces so we should use the
btrfs_inode.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-12-05 18:00:51 +01:00
David Sterba
ad65ecf30b btrfs: simplify btree_submit_bio_start and btrfs_submit_bio_start parameters
After previous patches the unused parameters can be removed from
btree_submit_bio_start and btrfs_submit_bio_start as they don't need to
conform to the extent_submit_bio_start_t typedef.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-12-05 18:00:51 +01:00
David Sterba
ab2072b292 btrfs: change how submit bio callback is passed to btrfs_wq_submit_bio
There's a callback function parameter for btrfs_wq_submit_bio that can
be one of: metadata, buffered data, direct io data. The callback
abstraction is unnecessary as we have all functions available.

Replace the parameter with a command that leads to a direct call in
run_one_async_start. The called functions can be then simplified and we
can also remove the extent_submit_bio_start_t typedef.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-12-05 18:00:51 +01:00
Qu Wenruo
1a1a285139 btrfs: remove the unused endio_raid56_workers and btrfs_raid_bio::end_io_work
Since we have switched all raid56 workload to submit-and-wait method,
there is no use for btrfs_fs_info::endio_raid56_workers workqueue and
btrfs_raid_bio::end_io_work.

Remove them to save some memory.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-12-05 18:00:49 +01:00
Josef Bacik
c03b22076b btrfs: move super prototypes into super.h
Move these out of ctree.h into super.h to cut down on code in ctree.h.

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>
2022-12-05 18:00:47 +01:00
Josef Bacik
2fc6822c99 btrfs: move scrub prototypes into scrub.h
Move these out of ctree.h into scrub.h to cut down on code in ctree.h.

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>
2022-12-05 18:00:47 +01:00
Josef Bacik
677074792a btrfs: move relocation prototypes into relocation.h
Move these out of ctree.h into relocation.h to cut down on code in
ctree.h

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>
2022-12-05 18:00:47 +01:00
Josef Bacik
c7a03b524d btrfs: move uuid tree prototypes to uuid-tree.h
Move these out of ctree.h into uuid-tree.h to cut down on the code in
ctree.h.

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>
2022-12-05 18:00:46 +01:00
Josef Bacik
59b818e064 btrfs: move defrag related prototypes to their own header
Now that the defrag code is all in one file, create a defrag.h and move
all the defrag related prototypes and helper out of ctree.h and into
defrag.h.

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>
2022-12-05 18:00:46 +01:00
Josef Bacik
45c40c8f95 btrfs: move root tree prototypes to their own header
Move all the root-tree.c prototypes to root-tree.h, and then update all
the necessary files to include the new header.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-12-05 18:00:44 +01:00
Josef Bacik
a0231804af btrfs: move extent-tree helpers into their own header file
Move all the extent tree related prototypes to extent-tree.h out of
ctree.h, and then go include it everywhere needed so everything
compiles.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-12-05 18:00:44 +01:00
Josef Bacik
07e81dc944 btrfs: move accessor helpers into accessors.h
This is a large patch, but because they're all macros it's impossible to
split up.  Simply copy all of the item accessors in ctree.h and paste
them in accessors.h, and then update any files to include the header so
everything compiles.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ reformat comments, style fixups ]
Signed-off-by: David Sterba <dsterba@suse.com>
2022-12-05 18:00:42 +01:00
Josef Bacik
55e5cfd36d btrfs: remove fs_info::pending_changes and related code
Now that we're not using this code anywhere we can remove it as well as
the member from fs_info.

We don't have any mount options or on/off features that would utilize
the pending infrastructure, the last one was inode_cache.
There was a patchset [1] to enable some features from sysfs that would
break things if it would be set immediately. In case we'll need that
kind of logic again the patch can be reverted, but for the current use
it can be replaced by the single state bit to do the commit.

[1] https://lore.kernel.org/linux-btrfs/1422609654-19519-1-git-send-email-quwenruo@cn.fujitsu.com/

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add note ]
Signed-off-by: David Sterba <dsterba@suse.com>
2022-12-05 18:00:42 +01:00
Josef Bacik
c7f13d428e btrfs: move fs wide helpers out of ctree.h
We have several fs wide related helpers in ctree.h.  The bulk of these
are the incompat flag test helpers, but there are things such as
btrfs_fs_closing() and the read only helpers that also aren't directly
related to the ctree code.  Move these into a fs.h header, which will
serve as the location for file system wide related helpers.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-12-05 18:00:41 +01:00
David Sterba
63a7cb1307 btrfs: auto enable discard=async when possible
There's a request to automatically enable async discard for capable
devices. We can do that, the async mode is designed to wait for larger
freed extents and is not intrusive, with limits to iops, kbps or latency.

The status and tunables will be exported in /sys/fs/btrfs/FSID/discard .

The automatic selection is done if there's at least one discard capable
device in the filesystem (not capable devices are skipped). Mounting
with any other discard option will honor that option, notably mounting
with nodiscard will keep it disabled.

Link: https://lore.kernel.org/linux-btrfs/CAEg-Je_b1YtdsCR0zS5XZ_SbvJgN70ezwvRwLiCZgDGLbeMB=w@mail.gmail.com/
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-12-05 18:00:41 +01:00
Josef Bacik
51129b33d3 btrfs: move btrfs_get_block_group helper out of disk-io.h
This inline helper calls btrfs_fs_compat_ro(), which is defined in
another header.  To avoid weird header dependency problems move this
helper into disk-io.c with the rest of the global root helpers.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-12-05 18:00:36 +01:00
Peng Hao
c1b078545e btrfs: simplify cleanup after error in btrfs_create_tree
Since leaf is already NULL, and no other branch will go to fail_unlock,
the fail_unlock label is useless and can be removed

Signed-off-by: Peng Hao <flyingpeng@tencent.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-12-05 18:00:36 +01:00
Johannes Thumshirn
a8d1b1647b btrfs: zoned: initialize device's zone info for seeding
When performing seeding on a zoned filesystem it is necessary to
initialize each zoned device's btrfs_zoned_device_info structure,
otherwise mounting the filesystem will cause a NULL pointer dereference.

This was uncovered by fstests' testcase btrfs/163.

CC: stable@vger.kernel.org # 5.15+
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-11-07 14:35:24 +01:00