Commit Graph

6 Commits

Author SHA1 Message Date
Qu Wenruo
fc6925bfd3 btrfs-progs: avoid repeated data write for metadata
[BUG]
Shinichiro reported that "mkfs.btrfs -m DUP" is doing repeated write
into the device.
For non-zoned device this is not a big deal, but for zoned device this
is critical, as zoned device doesn't support overwrite at all.

[CAUSE]
The problem is related to write_and_map_eb() call, since commit
2a93728391 ("btrfs-progs: use write_data_to_disk() to replace
write_extent_to_disk()"), we call write_data_to_disk() for metadata
write back.

But the problem is, write_data_to_disk() will call btrfs_map_block()
with rw = WRITE.

By that btrfs_map_block() will always return all stripes, while in
write_data_to_disk() we also iterate through each mirror of the range.

This results above repeated writeback.

[FIX]
Fix this problem by completely remove @mirror argument
from write_data_to_disk().
With extra comments to explicitly show that function will write to
all mirrors.

Reported-by: Shinichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Fixes: 2a93728391 ("btrfs-progs: use write_data_to_disk() to replace write_extent_to_disk()")
Tested-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-08-16 15:18:12 +02:00
David Sterba
0f65bf66be btrfs-progs: libbtrfs: drop ifdef BTRFS_FLAT_INCLUDES where not necessary
Headers that are only exported and not used for build do not need the
BTRFS_FLAT_INCLUDES switch (between local and installed headers). Now
that there are local copies of the shared headers drop the respective
part from local headers.

Signed-off-by: David Sterba <dsterba@suse.com>
2022-06-06 15:48:52 +02:00
Qu Wenruo
a99bece1cd btrfs-progs: remove extent_buffer::fd and extent_buffer::dev_bytes
Those two members are a shortcut for non-RAID56 profiles.

But we should not use such shortcut, and move all our logical address
read/write to the unified read_data_from_disk()/write_data_to_disk().

With previous refactors, now we're safe to remove them.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-04-25 19:08:30 +02:00
Qu Wenruo
3ff9d35257 btrfs-progs: use read_data_from_disk() to replace read_extent_from_disk() and replace read_extent_data()
The function read_extent_from_disk() is only a wrapper to read tree
block.

And read_extent_data() is just a while loop to eliminate short read
caused by stripe boundary.

In fact, a lot of call sites of read_extent_data() are either reading
metadata (thus no possible short read) or doing extra loop by
themselves.

This patch will replace those two functions with read_data_from_disk(),
making it the only entrance for data/metadata read.
And update read_data_from_disk() to return the read bytes, so caller can
do a simple while loop.

For the few callers of read_extent_data(), open-code a small while loop
for them.

This will allow later RAID56 read repair using P/Q much easier.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-04-25 19:08:30 +02:00
Qu Wenruo
2a93728391 btrfs-progs: use write_data_to_disk() to replace write_extent_to_disk()
Function write_extent_to_disk() is just writing the content of a tree
block to disk.

It can not handle RAID56, and its work is the same as
write_data_to_disk().

Thus we can replace write_extent_to_disk() with write_data_to_disk()
easily.

There is only one special call site in write_raid56_with_parity(), which
can easily be replace with btrfs_pwrite() directly.

This reduce the write entrance, and make later eb::fd removal easier.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-04-25 19:08:29 +02:00
David Sterba
4e49bd703d btrfs-progs: move extent_io.c to kernel-shared/
Signed-off-by: David Sterba <dsterba@suse.com>
2020-08-31 17:01:04 +02:00