btrfs-progs has a cache tree embedded in the extent_io_tree in order to
track extent buffers. We use the extent_io_tree part to track dirty,
and the cache tree to keep the extent buffers in. When we sync
extent-io-tree.[ch] we'll lose this ability, so separate out the dirty
tracking into its own extent_io_tree. Subsequent patches will adjust
the extent buffer lookup so it doesn't use the custom extent_io_tree
thing.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This is a cleanup patch to make syncing the btrfs kernel code into
btrfs-progs easier. In btrfs-progs we have an extra cache in the
extent_io_tree that's exclusively used for the extent buffer tracking.
In order to untangle this dependency start passing around the fs_info to
search for extent_buffers, and then have the helpers use the appropriate
structure to find the extent buffer.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
[BUG]
If we emulate a write error during commit transaction, by setting the
block device read-only, then we can easily have the following crash
using "btrfs check --clear-space-cache v2":
Opening filesystem to check...
Checking filesystem on /dev/test/scratch1
UUID: 5945915b-37f1-4bfa-9f64-684b318b8f73
Clear free space cache v2
Error writing to device 1
kernel-shared/transaction.c:156: __commit_transaction: BUG_ON `ret` triggered, value 1
./btrfs(+0x570c9)[0x562ec894f0c9]
./btrfs(+0x57167)[0x562ec894f167]
./btrfs(__commit_transaction+0x13b)[0x562ec894f7f2]
./btrfs(btrfs_commit_transaction+0x214)[0x562ec894fa64]
./btrfs(btrfs_clear_free_space_tree+0x177)[0x562ec8941ae6]
./btrfs(+0xc8958)[0x562ec89c0958]
./btrfs(+0xc9d53)[0x562ec89c1d53]
./btrfs(+0x17ec7)[0x562ec890fec7]
./btrfs(main+0x12f)[0x562ec8910908]
/usr/lib/libc.so.6(+0x232d0)[0x7ff917ee82d0]
/usr/lib/libc.so.6(__libc_start_main+0x8a)[0x7ff917ee838a]
./btrfs(_start+0x25)[0x562ec890fdc5]
Aborted (core dumped)
[CAUSE]
The call trace has shown it's a BUG_ON(), and it's from
__commit_transaction(), which is writing tree blocks back.
[FIX]
The fix is pretty simple, just return error.
In fact we even have an error value check in btrfs_commit_transaction()
just after __commit_transaction() call (although not catching the return
value from it).
And since we're here, also call btrfs_abort_transaction() to prevent
newer transactions from being started.
Now we won't have a full crash:
Opening filesystem to check...
Checking filesystem on /dev/test/scratch1
UUID: 5945915b-37f1-4bfa-9f64-684b318b8f73
Clear free space cache v2
Error writing to device 1
ERROR: failed to write bytenr 30425088 length 16384: Operation not permitted
ERROR: failed to write tree block 30425088: Operation not permitted
ERROR: failed to clear free space cache v2: -1
extent buffer leak: start 30720000 len 16384
Reported-by: Christoph Anton Mitterer <calestyo@scientia.org>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Function btrfs_start_transaction() will allocate the memory
unconditionally, but if the fs has an aborted transaction we don't free
the allocated memory but return error directly.
Fix it by only allocate the new memory after all the checks.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This adds the ability to load the block group root, as well as make sure
the various backup super block and super block updates are made
appropriately.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Tree manipulating operations like merging nodes often release
once-allocated tree nodes. Btrfs cleans such nodes so that pages in the
node are not uselessly written out. On ZONED drives, however, such
optimization blocks the following IOs as the cancellation of the write
out of the freed blocks breaks the sequential write sequence expected by
the device.
Check if next dirty extent buffer is continuous to a previously written
one. If not, it redirty extent buffers between the previous one and the
next one, so that all dirty buffers are written sequentially.
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Josef Bacik
Qu Wenruo
Naohiro Aota
David Sterba