Commit Graph

1187122 Commits

Author SHA1 Message Date
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
d85512d54e btrfs: add and fix comments in btrfs_fs_devices
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
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
a3c54b0be1 btrfs: simplify how changed fsid and metadata_uuid is checked
We often check if the metadata_uuid is not the same as fsid, and then we
check if the given fsid matches the metadata_uuid. This patch refactors
this logic into function match_fsid_changed and utilize it.

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
1a89834500 btrfs: simplify fsid and metadata_uuid comparisons
Refactor the functions find_fsid() and find_fsid_with_metadata_uuid(),
as they currently share a common set of code to compare the fsid and
metadata_uuid. Create a common helper function, match_fsid_fs_devices().

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
Anand Jain
f62c302e6d btrfs: add comment about metadata_uuid in btrfs_fs_devices
Add comment about metadata_uuid in btrfs_fs_devices.
No functional change.

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
c6930d7d11 btrfs: merge calls to alloc_fs_devices in device_list_add
Simplify has_metadata_uuid checks - by localizing the has_metadata_uuid
checked within alloc_fs_devices()'s second argument, it improves the
code readability.

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
19c4c49ca9 btrfs: streamline fsid checks in alloc_fs_devices
We currently have redundant checks for the non-null value of fsid
simplify it.

And, no one is using alloc_fs_devices() with a NULL metadata_uuid
while fsid is not NULL, add an assert() to verify this condition.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19 13:59:28 +02:00
Anand Jain
4693893bf8 btrfs: reduce struct btrfs_fs_devices size by moving fsid_change
Pack bool fsid_change and bool seeding with other bool declarations in the
struct btrfs_fs_devices, approximately 6 bytes is saved, depending on
the config.

   before: 512 bytes
   after: 496 bytes

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19 13:59:28 +02:00
Christoph Hellwig
46672a44b0 btrfs: merge write_one_subpage_eb into write_one_eb
Most of the code in write_one_subpage_eb and write_one_eb is shared,
so merge the two functions into one.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.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
d7172f52e9 btrfs: use per-buffer locking for extent_buffer reading
Instead of locking and unlocking every page or the extent, just add a
new EXTENT_BUFFER_READING bit that mirrors EXTENT_BUFFER_WRITEBACK
for synchronizing threads trying to read an extent_buffer and to wait
for I/O completion.

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
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
f3d315eb93 btrfs: don't check for uptodate pages in read_extent_buffer_pages
The only place that reads in pages and thus marks them uptodate for
the btree inode is read_extent_buffer_pages.  Which means that either
pages are already uptodate from an old buffer when creating a new
one in alloc_extent_buffer, or they will be updated by ca call
to read_extent_buffer_pages.  This means the checks for uptodate
pages in read_extent_buffer_pages and read_extent_buffer_subpage are
superfluous and can be removed.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.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
011134f444 btrfs: stop using PageError for extent_buffers
PageError is only used to limit the uptodate check in
assert_eb_page_uptodate.  But we have a much more useful flag indicating
the exact condition we are about with the EXTENT_BUFFER_WRITE_ERR flag,
so use that instead and help the kernel toward eventually removing
PageError.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.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
113fa05c2f btrfs: remove the io_pages field in struct extent_buffer
No need to track the number of pages under I/O now that each
extent_buffer is read and written using a single bio.  For the
read side we need to grab an extra reference for the duration of
the I/O to prevent eviction, though.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.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
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
cd88a4fdbf btrfs: use a separate end_io handler for extent_buffer writing
Now that we always use a single bio to write an extent_buffer, the buffer
can be passed to the end_io handler as private data.  This allows
to simplify the metadata write end I/O handler, and merge the subpage
end_io handler into the main one.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.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
b51e6b4bda btrfs: don't use btrfs_bio_ctrl for extent buffer writing
The btrfs_bio_ctrl machinery is overkill for writing extent_buffers
as we always operate on PAGE_SIZE chunks (or one smaller one for the
subpage case) that are contiguous and are guaranteed to fit into a
single bio.  Replace it with open coded btrfs_bio_alloc, __bio_add_page
and btrfs_submit_bio calls.

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
81a79b6ae4 btrfs: move page locking from lock_extent_buffer_for_io to write_one_eb
Locking the pages in lock_extent_buffer_for_io only for the non-subpage
case is very confusing.  Move it to write_one_eb to mirror the subpage
case and simplify the code. Now lock_extent_buffer_for_io does not leave
all the pages locked and each is individually locked/unlocked in
write_one_eb.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.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
50b21d7a06 btrfs: submit a writeback bio per extent_buffer
Stop trying to cluster writes of multiple extent_buffers into a single
bio.  There is no need for that as the blk_plug mechanism used all the
way up in writeback_inodes_wb gives us the same I/O pattern even with
multiple bios.  Removing the clustering simplifies
lock_extent_buffer_for_io a lot and will also allow passing the eb
as private data to the end I/O handler.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.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
9fdd160160 btrfs: return bool from lock_extent_buffer_for_io
lock_extent_buffer_for_io never returns a negative error value, so switch
the return value to a simple bool.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
[ keep noinline_for_stack ]
Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19 13:59:27 +02:00
Christoph Hellwig
3d66b4b27d btrfs: do not try to unlock the extent for non-subpage metadata reads
Only subpage metadata reads lock the extent.  Don't try to unlock it and
waste cycles in the extent tree lookup for PAGE_SIZE or larger metadata.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.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
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
e194931076 btrfs: remove the mirror_num argument to btrfs_submit_compressed_read
Given that read recovery for data I/O is handled in the storage layer,
the mirror_num argument to btrfs_submit_compressed_read is always 0,
so remove it.

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
b78b98e06f btrfs: don't use btrfs_bio_ctrl for extent buffer reading
The btrfs_bio_ctrl machinery is overkill for reading extent_buffers
as we always operate on PAGE_SIZE chunks (or one smaller one for the
subpage case) that are contiguous and are guaranteed to fit into a
single bio.  Replace it with open coded btrfs_bio_alloc, __bio_add_page
and btrfs_submit_bio calls in a helper function shared between
the subpage and node size >= PAGE_SIZE cases.

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
e95382834c btrfs: always read the entire extent_buffer
Currently read_extent_buffer_pages skips pages that are already uptodate
when reading in an extent_buffer.  While this reduces the amount of data
read, it increases the number of I/O operations as we now need to do
multiple I/Os when reading an extent buffer with one or more uptodate
pages in the middle of it.  On any modern storage device, be that hard
drives or SSDs this actually decreases I/O performance.  Fortunately
this case is pretty rare as the pages are always initially read together
and then aged the same way.  Besides simplifying the code a bit as-is
this will allow for major simplifications to the I/O completion handler
later on.

Note that the case where all pages are uptodate is still handled by an
optimized fast path that does not read any data from disk.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.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
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
243984b3b9 btrfs: subpage: fix error handling in end_bio_subpage_eb_writepage
Call btrfs_page_clear_uptodate instead of ClearPageUptodate to properly
manage the uptodate bit for the subpage case.

Reported-by: Qu Wenruo <wqu@suse.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
7f26fb1c13 btrfs: mark extent_buffer_under_io static
extent_buffer_under_io is only used in extent_io.c, so mark it static.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.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
Qu Wenruo
edc728814f btrfs: trigger orphan inode cleanup during START_SYNC ioctl
There is an internal error report that scrub found an error in an orphan
inode's data.

However there are very limited ways to cleanup such orphan inodes:

- btrfs_start_pre_rw_mount()
  This happens at either mount, or RO->RW switch.
  This is not a viable solution for root fs which may not be unmounted
  or RO mounted.

  Furthermore this doesn't cover every subvolume, it only covers the
  currently cached subvolumes.

- btrfs_lookup_dentry()
  This happens when we first lookup the subvolume dentry.
  But dentry can be cached thus it's not ensured to be triggered every
  time.

- create_snapshot()
  This only happens for the created snapshot, not the source one.

This means if we didn't trigger orphan items cleanup, there is really no
other way to manually trigger it. Add this step to the START_SYNC ioctl.
This is a slight change in the semantics of the ioctl but as sync can be
potentially slow and is usually paired with WAIT_SYNC ioctl.

The errors are not handled because the main point of the ioctl is the
async commit, orphan cleanup is a side effect.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19 13:59:26 +02:00
Filipe Manana
618d1d7da5 btrfs: fix comment referring to no longer existing btrfs_clean_tree_block()
There's a comment at btrfs_init_new_buffer() that refers to a function
named btrfs_clean_tree_block(), however the function was renamed to
btrfs_clear_buffer_dirty() in commit 190a83391b ("btrfs: rename
btrfs_clean_tree_block to btrfs_clear_buffer_dirty"). So update the
comment to refer to the current name.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19 13:59:26 +02:00
Filipe Manana
59fcf38817 btrfs: change for_rename argument of btrfs_record_unlink_dir() to bool
The for_rename argument of btrfs_record_unlink_dir() is defined as an
integer, but the argument is in fact used as a boolean. So change it to
a boolean to make its use more clear.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19 13:59:26 +02:00
Filipe Manana
acfb5a4f11 btrfs: remove pointless label and goto at btrfs_record_unlink_dir()
There's no point of having a label and goto at btrfs_record_unlink_dir()
because the function is trivial and can just return early if we are not
in a rename context. So remove the label and goto and instead return
early if we are not in a rename.

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 13:59:26 +02:00
Filipe Manana
1e75ef039d btrfs: update comments at btrfs_record_unlink_dir() to be more clear
Update the comments at btrfs_record_unlink_dir() so that they mention
where new names are logged and where old names are removed. Also, while
at it make the width of the comments closer to 80 columns and capitalize
the sentences and finish them with punctuation.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19 13:59:26 +02:00
Filipe Manana
d67ba263f4 btrfs: use inode_logged() at btrfs_record_unlink_dir()
At btrfs_record_unlink_dir() we directly check the logged_trans field of
the given inodes to check if they were previously logged in the current
transaction, and if any of them were, then we can avoid setting the field
last_unlink_trans of the directory to the id of the current transaction if
we are in a rename path. Avoiding that can later prevent falling back to
a transaction commit if anyone attempts to log the directory.

However the logged_trans field, store in struct btrfs_inode, is transient,
not persisted in the inode item on its subvolume b+tree, so that means
that if an inode is evicted and then loaded again, its original value is
lost and it's reset to 0. So directly checking the logged_trans field can
lead to some false negative, and that only results in a performance impact
as mentioned before.

Instead of directly checking the logged_trans field of the inodes, use the
inode_logged() helper, which will check in the log tree if an inode was
logged before in case its logged_trans field has a value of 0. This way
we can avoid setting the directory inode's last_unlink_trans and cause
future logging attempts of it to fallback to transaction commits. The
following test script shows one example where this happens without this
patch:

  $ cat test.sh
  #!/bin/bash

  DEV=/dev/nullb0
  MNT=/mnt/nullb0

  num_init_files=10000
  num_new_files=10000

  mkfs.btrfs -f $DEV
  mount -o ssd $DEV $MNT

  mkdir $MNT/testdir
  for ((i = 1; i <= $num_init_files; i++)); do
      echo -n > $MNT/testdir/file_$i
   done

  echo -n > $MNT/testdir/foo

  sync

  # Add some files so that there's more work in the transaction other
  # than just renaming file foo.
  for ((i = 1; i <= $num_new_files; i++)); do
      echo -n > $MNT/testdir/new_file_$i
  done

  # Change the file, fsync it.
  setfattr -n user.x1 -v 123 $MNT/testdir/foo
  xfs_io -c "fsync" $MNT/testdir/foo

  # Now triggger eviction of file foo but no eviction for our test
  # directory, since it is being used by the process below. This will
  # set logged_trans of the file's inode to 0 once it is loaded again.
  (
      cd $MNT/testdir
      while true; do
          :
      done
  ) &
  pid=$!

  echo 2 > /proc/sys/vm/drop_caches

  kill $pid
  wait $pid

  # Move foo out of our testdir. This will set last_unlink_trans
  # of the directory inode to the current transaction, because
  # logged_trans of both the directory and the file are set to 0.
  mv $MNT/testdir/foo $MNT/foo

  # Change file foo again and fsync it.
  # This fsync will result in a transaction commit because the rename
  # above has set last_unlink_trans of the parent directory to the id
  # of the current transaction and because our inode for file foo has
  # last_unlink_trans set to the current transaction, since it was
  # evicted and reloaded and it was previously modified in the current
  # transaction (the xattr addition).
  xfs_io -c "pwrite 0 64K" $MNT/foo
  start=$(date +%s%N)
  xfs_io -c "fsync" $MNT/foo
  end=$(date +%s%N)
  dur=$(( (end - start) / 1000000 ))

  echo "file fsync took: $dur milliseconds"

  umount $MNT

Before this patch:   fsync took 19 milliseconds
After this patch:    fsync took  5 milliseconds

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19 13:59:26 +02:00
Filipe Manana
bf1f4fd3fa btrfs: use inode_logged() at need_log_inode()
At need_log_inode() we directly check the ->logged_trans field of the
given inode to check if it was previously logged in the transaction, with
the goal of skipping logging the inode again when it's not necessary.
The ->logged_trans field in not persisted in the inode item or elsewhere,
it's only stored in memory (struct btrfs_inode), so it's transient and
lost once the inode is evicted and then loaded again. Once an inode is
loaded, we are conservative and set ->logged_trans to 0, which may mean
that either the inode was never logged in the current transaction or it
was logged but evicted before being loaded again.

Instead of checking the inode's ->logged_trans field directly, we can
use instead the helper inode_logged(), which will really check if the
inode was logged before in the current transaction in case we have a
->logged_trans field with a value of 0. This will prevent unnecessarily
logging an inode when it's not needed, and in some cases preventing a
transaction commit, in case the logging requires a fallback to a
transaction commit. The following test script shows a scenario where
due to eviction we fallback a transaction commit when trying to fsync
a file that was renamed:

  $ cat test.sh
  #!/bin/bash

  DEV=/dev/nullb0
  MNT=/mnt/nullb0

  num_init_files=10000
  num_new_files=10000

  mkfs.btrfs -f $DEV
  mount -o ssd $DEV $MNT

  mkdir $MNT/testdir
  for ((i = 1; i <= $num_init_files; i++)); do
      echo -n > $MNT/testdir/file_$i
  done

  echo -n > $MNT/testdir/foo

  sync

  # Add some files so that there's more work in the transaction other
  # than just renaming file foo.
  for ((i = 1; i <= $num_new_files; i++)); do
      echo -n > $MNT/testdir/new_file_$i
  done

  # Fsync the directory first.
  xfs_io -c "fsync" $MNT/testdir

  # Rename file foo.
  mv $MNT/testdir/foo $MNT/testdir/bar

  # Now trigger eviction of the test directory's inode.
  # Once loaded again, it will have logged_trans set to 0 and
  # last_unlink_trans set to the current transaction.
  echo 2 > /proc/sys/vm/drop_caches

  # Fsync file bar (ex-foo).
  # Before the patch the fsync would result in a transaction commit
  # because the inode for file bar has last_unlink_trans set to the
  # current transaction, so it will attempt to log the parent directory
  # as well, which will fallback to a full transaction commit because
  # it also has its last_unlink_trans set to the current transaction,
  # due to the inode eviction.
  start=$(date +%s%N)
  xfs_io -c "fsync" $MNT/testdir/bar
  end=$(date +%s%N)
  dur=$(( (end - start) / 1000000 ))

  echo "file fsync took: $dur milliseconds"

  umount $MNT

Before this patch:  fsync took 22 milliseconds
After this patch:   fsync took  8 milliseconds

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19 13:59:26 +02:00
Jiapeng Chong
b9cb105e73 btrfs: scrub: remove more unused functions
These functions are defined in the scrub.c file, but last callers were
removed in e9255d6c40 ("btrfs: scrub: remove the old scrub recheck
code").

fs/btrfs/scrub.c:553:20: warning: unused function 'scrub_stripe_index_and_offset'.
fs/btrfs/scrub.c:543:19: warning: unused function 'scrub_nr_raid_mirrors'.

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Link: https://bugzilla.openanolis.cn/show_bug.cgi?id=4937
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19 13:59:26 +02:00
Qu Wenruo
b7f9945a14 btrfs: handle tree backref walk error properly
[BUG]
Smatch reports the following errors related to commit ("btrfs: output
affected files when relocation fails"):

	fs/btrfs/inode.c:283 print_data_reloc_error()
	error: uninitialized symbol 'ref_level'.

[CAUSE]
That part of code is mostly copied from scrub, but unfortunately scrub
code from the beginning is not doing the error handling properly.

The offending code looks like this:

	do {
		ret = tree_backref_for_extent();
		btrfs_warn_rl();
	} while (ret != 1);

There are several problems involved:

- No error handling
  If that tree_backref_for_extent() failed, we would output the same
  error again and again, never really exit as it requires ret == 1 to
  exit.

- Always do one extra output
  As tree_backref_for_extent() only return > 0 if there is no more
  backref item.
  This means after the last item we hit, we would output an invalid
  error message for ret > 0 case.

[FIX]
Fix the old code by:

- Move @ref_root and @ref_level into the if branch
  And do not initialize them, so we can catch such uninitialized values
  just like what we do in the inode.c

- Explicitly check the return value of tree_backref_for_extent()
  And handle ret < 0 and ret > 0 cases properly.

- No more do {} while () loop
  Instead go while (true) {} loop since we will handle @ret manually.

Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19 13:59:26 +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
Johannes Thumshirn
bb5167e619 btrfs: unexport btrfs_run_discard_work and make it static
Mark btrfs_run_discard_work static and move it above its callers.

Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19 13:59:25 +02:00
Josef Bacik
016f9d0b74 btrfs: rename del_ptr to btrfs_del_ptr and export it
This exists internal to ctree.c, however btrfs check needs to use it for
some of its operations.  I'd rather not duplicate that code inside of
btrfs check as this is low level and I want to keep this code in one
place, so rename the function to btrfs_del_ptr and export it so that it
can be used inside of btrfs-progs safely.  Add a comment to make sure
this doesn't get removed by a future cleanup.

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
b3cbfb0dd4 btrfs: add a btrfs_csum_type_size helper
This is needed in btrfs-progs for the tools that convert the checksum
types for file systems and a few other things.  We don't have it in the
kernel as we just want to get the size for the super blocks type.
However I don't want to have to manually add this every time we sync
ctree.c into btrfs-progs, so add the helper in the kernel with a note so
it doesn't get removed by a later cleanup.

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
a95b7f9360 btrfs: add __KERNEL__ check for btrfs_no_printk
We want to override this in btrfs-progs, so wrap this in the __KERNEL__
check so we can easily sync this to btrfs-progs and have our local
version of btrfs_no_printk do the work.

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
f541833c8e btrfs: move split_flags/combine_flags helpers to inode-item.h
These are more related to the inode item flags on disk than the
in-memory btrfs_inode, move the helpers to inode-item.h.

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
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
c26fa931eb btrfs: add __btrfs_check_node helper
This helper returns a btrfs_tree_block_status for the various errors,
and then btrfs_check_node() will return -EUCLEAN if it gets anything
other than BTRFS_TREE_BLOCK_CLEAN which will be used by the kernel.  In
the future btrfs-progs will use this helper instead.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19 13:59:25 +02:00