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| author | Qu Wenruo <wqu@suse.com> | 2021-01-21 07:13:54 +0100 |
|---|---|---|
| committer | David Sterba <dsterba@suse.com> | 2021-02-08 22:58:52 +0100 |
| commit | 3c198fe064491dcceaed9e15c6c997e92e71293e (patch) | |
| tree | e1df2fec9f5767705ba6ee91328f35edaa864aec /include/trace/events | |
| parent | btrfs: remove redundant NULL check before kvfree (diff) | |
| download | linux-3c198fe064491dcceaed9e15c6c997e92e71293e.tar.xz linux-3c198fe064491dcceaed9e15c6c997e92e71293e.zip | |
btrfs: rework the order of btrfs_ordered_extent::flags
[BUG]
There is a long existing bug in the last parameter of
btrfs_add_ordered_extent(), in commit 771ed689d2cd ("Btrfs: Optimize
compressed writeback and reads") back to 2008.
In that ancient commit btrfs_add_ordered_extent() expects the @type
parameter to be one of the following:
- BTRFS_ORDERED_REGULAR
- BTRFS_ORDERED_NOCOW
- BTRFS_ORDERED_PREALLOC
- BTRFS_ORDERED_COMPRESSED
But we pass 0 in cow_file_range(), which means BTRFS_ORDERED_IO_DONE.
Ironically extra check in __btrfs_add_ordered_extent() won't set the bit
if we see (type == IO_DONE || type == IO_COMPLETE), and avoid any
obvious bug.
But this still leads to regular COW ordered extent having no bit to
indicate its type in various trace events, rendering REGULAR bit
useless.
[FIX]
Change the following aspects to avoid such problem:
- Reorder btrfs_ordered_extent::flags
Now the type bits go first (REGULAR/NOCOW/PREALLCO/COMPRESSED), then
DIRECT bit, finally extra status bits like IO_DONE/COMPLETE/IOERR.
- Add extra ASSERT() for btrfs_add_ordered_extent_*()
- Remove @type parameter for btrfs_add_ordered_extent_compress()
As the only valid @type here is BTRFS_ORDERED_COMPRESSED.
- Remove the unnecessary special check for IO_DONE/COMPLETE in
__btrfs_add_ordered_extent()
This is just to make the code work, with extra ASSERT(), there are
limited values can be passed in.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Diffstat (limited to 'include/trace/events')
| -rw-r--r-- | include/trace/events/btrfs.h | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/include/trace/events/btrfs.h b/include/trace/events/btrfs.h index ecd24c719de4..b9896fc06160 100644 --- a/include/trace/events/btrfs.h +++ b/include/trace/events/btrfs.h @@ -499,12 +499,13 @@ DEFINE_EVENT( #define show_ordered_flags(flags) \ __print_flags(flags, "|", \ - { (1 << BTRFS_ORDERED_IO_DONE), "IO_DONE" }, \ - { (1 << BTRFS_ORDERED_COMPLETE), "COMPLETE" }, \ + { (1 << BTRFS_ORDERED_REGULAR), "REGULAR" }, \ { (1 << BTRFS_ORDERED_NOCOW), "NOCOW" }, \ - { (1 << BTRFS_ORDERED_COMPRESSED), "COMPRESSED" }, \ { (1 << BTRFS_ORDERED_PREALLOC), "PREALLOC" }, \ + { (1 << BTRFS_ORDERED_COMPRESSED), "COMPRESSED" }, \ { (1 << BTRFS_ORDERED_DIRECT), "DIRECT" }, \ + { (1 << BTRFS_ORDERED_IO_DONE), "IO_DONE" }, \ + { (1 << BTRFS_ORDERED_COMPLETE), "COMPLETE" }, \ { (1 << BTRFS_ORDERED_IOERR), "IOERR" }, \ { (1 << BTRFS_ORDERED_TRUNCATED), "TRUNCATED" }) |