btrfs: remove colon from messages with state

The message format in syslog is usually made of two parts:

prefix ":" message

Various tools parse the prefix up to the first ":". When there's
an additional status of a btrfs filesystem like

[5.199782] BTRFS info (device nvme1n1p1: state M): use zstd compression, level 9

where 'M' is for remount, there's one more ":" that does not conform to
the format. Remove it.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: remove unused included headers

With help of neovim, LSP and clangd we can identify header files that
are not actually needed to be included in the .c files. This is focused
only on removal (with minor fixups), further cleanups are possible but
will require doing the header files properly with forward declarations,
minimized includes and include-what-you-use care.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: constify fs_info parameter in __btrfs_panic()

The printk helpers take const fs_info if it's used just for the
identifier in the messages, __btrfs_panic() lacks that.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: rename errno identifiers to error

We sync the kernel files to userspace and the 'errno' symbol is defined
by standard library, which does not matter in kernel but the parameters
or local variables could clash. Rename them all.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

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>

btrfs: remove v0 extent handling

The v0 extent item has been deprecated for a long time, and we don't have
any report from the community either.

So it's time to remove the v0 extent specific error handling, and just
treat them as regular extent tree corruption.

This patch would remove the btrfs_print_v0_err() helper, and enhance the
involved error handling to treat them just as any extent tree
corruption. No reports regarding v0 extents have been seen since the
graceful handling was added in 2018.

This involves:

- btrfs_backref_add_tree_node()
This change is a little tricky, the new code is changed to only handle
BTRFS_TREE_BLOCK_REF_KEY and BTRFS_SHARED_BLOCK_REF_KEY.

But this is safe, as we have rejected any unknown inline refs through
btrfs_get_extent_inline_ref_type().
For keyed backrefs, we're safe to skip anything we don't know (that's
if it can pass tree-checker in the first place).

- btrfs_lookup_extent_info()
- lookup_inline_extent_backref()
- run_delayed_extent_op()
- __btrfs_free_extent()
- add_tree_block()
Regular error handling of unexpected extent tree item, and abort
transaction (if we have a trans handle).

- remove_extent_data_ref()
It's pretty much the same as the regular rejection of unknown backref
key.
But for this particular case, we can also remove a BUG_ON().

- extent_data_ref_count()
We can remove the BTRFS_EXTENT_REF_V0_KEY BUG_ON(), as it would be
rejected by the only caller.

- btrfs_print_leaf()
Remove the handling for BTRFS_EXTENT_REF_V0_KEY.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

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>

btrfs: print assertion failure report and stack trace from the same line

Assertions reports are split into two parts, the exact file and location
of the condition and then the stack trace printed from
btrfs_assertfail(). This means all the stack traces report the same line
and this is what's typically reported by various tools, making it harder
to distinguish the reports.

[403.2467] assertion failed: refcount_read(&block_group->refs) == 1, in fs/btrfs/block-group.c:4259
[403.2479] ------------[ cut here ]------------
[403.2484] kernel BUG at fs/btrfs/messages.c:259!
[403.2488] invalid opcode: 0000 [#1] PREEMPT SMP KASAN
[403.2493] CPU: 2 PID: 23202 Comm: umount Not tainted 6.2.0-rc4-default+ #67
[403.2499] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552-rebuilt.opensuse.org 04/01/2014
[403.2509] RIP: 0010:btrfs_assertfail+0x19/0x1b [btrfs]
...
[403.2595] Call Trace:
[403.2598] <TASK>
[403.2601] btrfs_free_block_groups.cold+0x52/0xae [btrfs]
[403.2608] close_ctree+0x6c2/0x761 [btrfs]
[403.2613] ? __wait_for_common+0x2b8/0x360
[403.2618] ? btrfs_cleanup_one_transaction.cold+0x7a/0x7a [btrfs]
[403.2626] ? mark_held_locks+0x6b/0x90
[403.2630] ? lockdep_hardirqs_on_prepare+0x13d/0x200
[403.2636] ? __call_rcu_common.constprop.0+0x1ea/0x3d0
[403.2642] ? trace_hardirqs_on+0x2d/0x110
[403.2646] ? __call_rcu_common.constprop.0+0x1ea/0x3d0
[403.2652] generic_shutdown_super+0xb0/0x1c0
[403.2657] kill_anon_super+0x1e/0x40
[403.2662] btrfs_kill_super+0x25/0x30 [btrfs]
[403.2668] deactivate_locked_super+0x4c/0xc0

By making btrfs_assertfail a macro we'll get the same line number for
the BUG output:

[63.5736] assertion failed: 0, in fs/btrfs/super.c:1572
[63.5758] ------------[ cut here ]------------
[63.5782] kernel BUG at fs/btrfs/super.c:1572!
[63.5807] invalid opcode: 0000 [#2] PREEMPT SMP KASAN
[63.5831] CPU: 0 PID: 859 Comm: mount Tainted: G D 6.3.0-rc7-default+ #2062
[63.5868] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a-rebuilt.opensuse.org 04/01/2014
[63.5905] RIP: 0010:btrfs_mount+0x24/0x30 [btrfs]
[63.5964] RSP: 0018:ffff88800e69fcd8 EFLAGS: 00010246
[63.5982] RAX: 000000000000002d RBX: ffff888008fc1400 RCX: 0000000000000000
[63.6004] RDX: 0000000000000000 RSI: ffffffffb90fd868 RDI: ffffffffbcc3ff20
[63.6026] RBP: ffffffffc081b200 R08: 0000000000000001 R09: ffff88800e69fa27
[63.6046] R10: ffffed1001cd3f44 R11: 0000000000000001 R12: ffff888005a3c370
[63.6062] R13: ffffffffc058e830 R14: 0000000000000000 R15: 00000000ffffffff
[63.6081] FS: 00007f7b3561f800(0000) GS:ffff88806c600000(0000) knlGS:0000000000000000
[63.6105] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[63.6120] CR2: 00007fff83726e10 CR3: 0000000002a9e000 CR4: 00000000000006b0
[63.6137] Call Trace:
[63.6143] <TASK>
[63.6148] legacy_get_tree+0x80/0xd0
[63.6158] vfs_get_tree+0x43/0x120
[63.6166] do_new_mount+0x1f3/0x3d0
[63.6176] ? do_add_mount+0x140/0x140
[63.6187] ? cap_capable+0xa4/0xe0
[63.6197] path_mount+0x223/0xc10

This comes at a cost of bloating the final btrfs.ko module due all the
inlining, as long as assertions are compiled in. This is a must for
debugging builds but this is often enabled on release builds too.

Release build:

text data bss dec hex filename
1251676 20317 16088 1288081 13a791 pre/btrfs.ko
1260612 29473 16088 1306173 13ee3d post/btrfs.ko

DELTA: +8936

CC: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: Mark btrfs_assertfail() __noreturn

Fixes a bunch of warnings including:

vmlinux.o: warning: objtool: select_reloc_root+0x314: unreachable instruction
vmlinux.o: warning: objtool: finish_inode_if_needed+0x15b1: unreachable instruction
vmlinux.o: warning: objtool: get_bio_sector_nr+0x259: unreachable instruction
vmlinux.o: warning: objtool: raid_wait_read_end_io+0xc26: unreachable instruction
vmlinux.o: warning: objtool: raid56_parity_alloc_scrub_rbio+0x37b: unreachable instruction
...

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/960bd9c0c9e3cfc409ba9c35a17644b11b832956.1681342859.git.jpoimboe@kernel.org

btrfs: mark btrfs_assertfail() __noreturn

Fixes a bunch of warnings including:

vmlinux.o: warning: objtool: select_reloc_root+0x314: unreachable instruction
vmlinux.o: warning: objtool: finish_inode_if_needed+0x15b1: unreachable instruction
vmlinux.o: warning: objtool: get_bio_sector_nr+0x259: unreachable instruction
vmlinux.o: warning: objtool: raid_wait_read_end_io+0xc26: unreachable instruction
vmlinux.o: warning: objtool: raid56_parity_alloc_scrub_rbio+0x37b: unreachable instruction
...

Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/oe-kbuild-all/202302210709.IlXfgMpX-lkp@intel.com/
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: move btrfs_abort_transaction to transaction.c

While trying to sync messages.[ch] I ended up with this dependency on
messages.h in the rest of btrfs-progs code base because it's where
btrfs_abort_transaction() was now held. We want to keep messages.[ch]
limited to the kernel code, and the btrfs_abort_transaction() code
better fits in the transaction code and not in messages.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ move the __cold attributes ]
Signed-off-by: David Sterba <dsterba@suse.com>

btrfs: move super_block specific helpers into super.h

This will make syncing fs.h to user space a little easier if we can pull
the super block specific helpers out of fs.h and put them in super.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>

btrfs: move the printk and assert helpers to messages.c

These helpers are core to btrfs, and in order to more easily sync
various parts of the btrfs kernel code into btrfs-progs we need to be
able to carry these helpers with us. However we want to have our own
implementation for the helpers themselves, currently they're implemented
in different files that we want to sync inside of btrfs-progs itself.
Move these into their own C file, this will allow us to contain our
overrides in btrfs-progs in it's own file without messing with the rest
of the codebase.

In copying things over I fixed up a few whitespace errors that already
existed.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>