The iterator is used only once and within build_backref_tree() so we can
avoid one allocation and place it on stack.
Signed-off-by: David Sterba <dsterba@suse.com>
The fs_info is available everywhere and we don't need to store it inside
a structure that is used within one function only, which is
build_backref_tree(). The size of btrfs_backref_iter is now 48 bytes.
Signed-off-by: David Sterba <dsterba@suse.com>
We have support for optional string to be printed in ASSERT() (added in
19468a623a ("btrfs: enhance ASSERT() to take optional format
string")), it's not yet everywhere it could be so add a few more files.
Try to finish what was left after 1c094e6cce ("btrfs: make a few
more ASSERTs verbose").
Signed-off-by: David Sterba <dsterba@suse.com>
We have several places that call extent_buffer_uptodate() after reading a
tree block with read_tree_block(), but that is redundant since we already
call extent_buffer_uptodate() in the call chain of read_tree_block():
read_tree_block()
btrfs_read_extent_buffer()
read_extent_buffer_pages()
returns -EIO if extent_buffer_uptodate() returns false
So remove those redundant checks.
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
-----BEGIN PGP SIGNATURE-----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=MYi5
-----END PGP SIGNATURE-----
Merge tag 'for-7.0-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
"Another batch of fixes for problems that have been identified by tools
analyzing code or by fuzzing. Most of them are short, two patches fix
the same thing in many places so the diffs are bigger.
- handle potential NULL pointer errors after attempting to read
extent and checksum trees
- prevent ENOSPC when creating many qgroups by ioctls in the same
transaction
- encoded write ioctl fixes (with 64K page and 4K block size):
- fix unexpected bio length
- do not let compressed bios and pages interfere with page cache
- compression fixes on setups with 64K page and 4K block size: fix
folio length assertions (zstd and lzo)
- remap tree fixes:
- make sure to hold block group reference while moving it
- handle early exit when moving block group to unused list
- handle deleted subvolumes with inconsistent state of deletion
progress"
* tag 'for-7.0-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: reject root items with drop_progress and zero drop_level
btrfs: check block group before marking it unused in balance_remap_chunks()
btrfs: hold block group reference during entire move_existing_remap()
btrfs: fix an incorrect ASSERT() condition inside lzo_decompress_bio()
btrfs: fix an incorrect ASSERT() condition inside zstd_decompress_bio()
btrfs: do not touch page cache for encoded writes
btrfs: fix a bug that makes encoded write bio larger than expected
btrfs: reserve enough transaction items for qgroup ioctls
btrfs: check for NULL root after calls to btrfs_csum_root()
btrfs: check for NULL root after calls to btrfs_extent_root()
btrfs_extent_root() can return a NULL pointer in case the root we are
looking for is not in the rb tree that tracks roots. So add checks to
every caller that is missing such check to log a message and return
an error. The same applies to callers of btrfs_block_group_root(),
since it calls btrfs_extent_root().
Reported-by: Chris Mason <clm@meta.com>
Link: https://lore.kernel.org/linux-btrfs/20260208161657.3972997-1-clm@meta.com/
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This was done entirely with mindless brute force, using
git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'
to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.
Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.
For the same reason the 'flex' versions will be done as a separate
conversion.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:
Single allocations: kmalloc(sizeof(TYPE), ...)
are replaced with: kmalloc_obj(TYPE, ...)
Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with: kmalloc_objs(TYPE, COUNT, ...)
Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...)
(where TYPE may also be *VAR)
The resulting allocations no longer return "void *", instead returning
"TYPE *".
Signed-off-by: Kees Cook <kees@kernel.org>
The return statement after btrfs_backref_panic() is unreachable since
btrfs_backref_panic() calls BUG() which never returns. Remove the
return to unify it with the other calls to btrfs_backref_panic().
Signed-off-by: Zhen Ni <zhen.ni@easystack.cn>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Many fields of struct btrfs_path are used as booleans but their type is
an unsigned int (of one 1 bit width to save space). Change the type to
bool keeping the :1 suffix so that they combine with the previous u8
fields in order to save space. This makes the code more clear by using
explicit true/false and more in line with the preferred style, preserving
the size of the structure.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The free_ipath() function was being used as a cleanup function
everywhere. Declare it via DEFINE_FREE() so we can use this function
with the __free() helper.
The name has also been adjusted so it's closer to the type's name.
Signed-off-by: Miquel Sabaté Solà <mssola@mssola.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Change all locations that print a key to use the new macros to print
them in order to ensure a consistent style and avoid repetitive code.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The unlikely() annotation is a static prediction hint that compiler may
use to reorder code out of hot path. We use it elsewhere (namely
tree-checker.c) for error branches that almost never happen, where
EIO is one of them.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The unlikely() annotation is a static prediction hint that compiler may
use to reorder code out of hot path. We use it elsewhere (namely
tree-checker.c) for error branches that almost never happen, where
EUCLEAN (a corruption) is one of them.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Annual typo fixing pass. Strangely codespell found only about 30% of
what is in this patch, the rest was done manually using text
spellchecker with a custom dictionary of acceptable terms.
Reviewed-by: Neal Gompa <neal@gompa.dev>
Signed-off-by: David Sterba <dsterba@suse.com>
There's no point in checking at iterate_inodes_from_logical() if the path
has search_commit_root set, the only caller never sets search_commit_root
to true and it doesn't make sense for it ever to be true for the current
use case (logical_to_ino ioctl). So stop checking for that and since the
only caller allocates the path just for it to be used by
iterate_inodes_from_logical(), move the path allocation into that function.
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The btrfs_debug() helpers depend on various config options. In case of
"no_printk" we don't need to define a special helper that in the end
does nothing but validates the parameters. As the default build config
is to validate the parameters we can simplify it to let the debug
helpers expand to nothing and remove btrfs_no_printk_in_rcu().
To avoid warnings use fs_info and inline one variable in
extent_from_logical().
Reviewed-by: Daniel Vacek <neelx@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Unify naming of return value to the preferred way, move the variable to
the closest scope.
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Replace struct embedding with union to enable safe type conversion in
btrfs_backref_node, tree_block and mapping_node.
Adjust function calls to use the new unified API, eliminating redundant
parameters.
Signed-off-by: Pan Chuang <panchuang@vivo.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_backref_link_edge() is always called with the LINK_LOWER argument.
We can simplify it and remove the LINK_LOWER and LINK_UPPER macros
completely.
The last call with LINK_UPPER was removed with commit 0097422c0d
("btrfs: remove clone_backref_node() from relocation").
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Daniel Vacek <neelx@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Using the helper makes it a bit more clear that we're accessing the
first list entry.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The use of ASSERT(0) is maybe useful for some cases but more like a
notice for developers. Assertions can be compiled in independently so
convert it to a debugging helper.
The difference is that it's just a warning and will not end up in BUG().
The converted cases are in connection with proper error handling.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Use the conditional warning instead of typing the whole condition.
Optional message is printed where it seems clear what could be the
problem.
Conversion is left out in btree_csum_one_bio() because of the additional
condition.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The btrfs_key is defined as objectid/type/offset and the keys are also
printed like that. For better readability, update all key
initializations to match this order.
Signed-off-by: David Sterba <dsterba@suse.com>
Update prelim_ref_insert() to use rb_find_add_cached().
There is a special change that the existing prelim_ref_compare() is
called with the first parameter as the existing ref in the rbtree.
But the newer rb_find_add_cached() expects the cmp() function to have
the first parameter as the to-be-added node, thus the new helper
prelim_ref_rb_add_cmp() need to adapt this new order.
Signed-off-by: Roger L. Beckermeyer III <beckerlee3@gmail.com>
Reviewed-by: Qu Wenruo <wqu@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>
We don't ever look at this list, remove it.
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Before we were keeping all of our nodes on various lists in order to
make sure everything got cleaned up correctly. We used node->lowest to
indicate that node->lower was linked into the cache->leaves list. Now
that we do cleanup based on the rb-tree both the list and the flag are
useless, so delete them both.
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We rely on finding all our nodes on the various lists in the backref
cache, when they are all also in the rbtree. Instead just search
through the rbtree and free everything.
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that we handle relocation for non-shareable roots without using the
backref cache, remove the ->cowonly field from the backref nodes and
update the handling to throw an error.
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that we're not updating the backref cache when we switch transids we
can remove the changed list.
We're going to keep the new_bytenr field because it serves as a good
sanity check for the backref cache and relocation, and can prevent us
from making extent tree corruption worse.
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
One of the following patches in the series will need to access fs_info in
the function find_ref_head(), so pass a fs_info argument to it as well as
to the functions btrfs_select_ref_head() and btrfs_find_delayed_ref_head()
which call find_ref_head().
Reviewed-by: Boris Burkov <boris@bur.io>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Since the inception of relocation we have maintained the backref cache
across transaction commits, updating the backref cache with the new
bytenr whenever we COWed blocks that were in the cache, and then
updating their bytenr once we detected a transaction id change.
This works as long as we're only ever modifying blocks, not changing the
structure of the tree.
However relocation does in fact change the structure of the tree. For
example, if we are relocating a data extent, we will look up all the
leaves that point to this data extent. We will then call
do_relocation() on each of these leaves, which will COW down to the leaf
and then update the file extent location.
But, a key feature of do_relocation() is the pending list. This is all
the pending nodes that we modified when we updated the file extent item.
We will then process all of these blocks via finish_pending_nodes, which
calls do_relocation() on all of the nodes that led up to that leaf.
The purpose of this is to make sure we don't break sharing unless we
absolutely have to. Consider the case that we have 3 snapshots that all
point to this leaf through the same nodes, the initial COW would have
created a whole new path. If we did this for all 3 snapshots we would
end up with 3x the number of nodes we had originally. To avoid this we
will cycle through each of the snapshots that point to each of these
nodes and update their pointers to point at the new nodes.
Once we update the pointer to the new node we will drop the node we
removed the link for and all of its children via btrfs_drop_subtree().
This is essentially just btrfs_drop_snapshot(), but for an arbitrary
point in the snapshot.
The problem with this is that we will never reflect this in the backref
cache. If we do this btrfs_drop_snapshot() for a node that is in the
backref tree, we will leave the node in the backref tree. This becomes
a problem when we change the transid, as now the backref cache has
entire subtrees that no longer exist, but exist as if they still are
pointed to by the same roots.
In the best case scenario you end up with "adding refs to an existing
tree ref" errors from insert_inline_extent_backref(), where we attempt
to link in nodes on roots that are no longer valid.
Worst case you will double free some random block and re-use it when
there's still references to the block.
This is extremely subtle, and the consequences are quite bad. There
isn't a way to make sure our backref cache is consistent between
transid's.
In order to fix this we need to simply evict the entire backref cache
anytime we cross transid's. This reduces performance in that we have to
rebuild this backref cache every time we change transid's, but fixes the
bug.
This has existed since relocation was added, and is a pretty critical
bug. There's a lot more cleanup that can be done now that this
functionality is going away, but this patch is as small as possible in
order to fix the problem and make it easy for us to backport it to all
the kernels it needs to be backported to.
Followup series will dismantle more of this code and simplify relocation
drastically to remove this functionality.
We have a reproducer that reproduced the corruption within a few minutes
of running. With this patch it survives several iterations/hours of
running the reproducer.
Fixes: 3fd0a5585e ("Btrfs: Metadata ENOSPC handling for balance")
CC: stable@vger.kernel.org
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Continue adding const to parameters. This is for clarity and minor
addition to safety. There are some minor effects, in the assembly code
and .ko measured on release config.
Signed-off-by: David Sterba <dsterba@suse.com>
A comment from Filipe on one of my previous cleanups brought my
attention to a new helper we have for getting the root id of a root,
which makes it easier to read in the code.
The changes where made with the following Coccinelle semantic patch:
// <smpl>
@@
expression E,E1;
@@
(
E->root_key.objectid = E1
|
- E->root_key.objectid
+ btrfs_root_id(E)
)
// </smpl>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ minor style fixups ]
Signed-off-by: David Sterba <dsterba@suse.com>
We only ever need to use this to get the level of the tree block ref, so
use the btrfs_delayed_ref_owner() helper, which returns the level for
the given reference.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that most of our elements are inside of btrfs_delayed_ref_node
directly and we have helpers for the delayed_data_ref bits, go ahead and
remove all direct usage of btrfs_delayed_data_ref and use the helpers
where needed.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
These two members are shared by both the tree refs and data refs, so
move them into btrfs_delayed_ref_node proper. This allows us to greatly
simplify the comparison code, as the shared refs always only sort on
parent, and the non shared refs always sort first on ref_root, and then
only data refs sort on their specific fields.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Syzbot reported the following information leak for in
btrfs_ioctl_logical_to_ino():
BUG: KMSAN: kernel-infoleak in instrument_copy_to_user include/linux/instrumented.h:114 [inline]
BUG: KMSAN: kernel-infoleak in _copy_to_user+0xbc/0x110 lib/usercopy.c:40
instrument_copy_to_user include/linux/instrumented.h:114 [inline]
_copy_to_user+0xbc/0x110 lib/usercopy.c:40
copy_to_user include/linux/uaccess.h:191 [inline]
btrfs_ioctl_logical_to_ino+0x440/0x750 fs/btrfs/ioctl.c:3499
btrfs_ioctl+0x714/0x1260
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:904 [inline]
__se_sys_ioctl+0x261/0x450 fs/ioctl.c:890
__x64_sys_ioctl+0x96/0xe0 fs/ioctl.c:890
x64_sys_call+0x1883/0x3b50 arch/x86/include/generated/asm/syscalls_64.h:17
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Uninit was created at:
__kmalloc_large_node+0x231/0x370 mm/slub.c:3921
__do_kmalloc_node mm/slub.c:3954 [inline]
__kmalloc_node+0xb07/0x1060 mm/slub.c:3973
kmalloc_node include/linux/slab.h:648 [inline]
kvmalloc_node+0xc0/0x2d0 mm/util.c:634
kvmalloc include/linux/slab.h:766 [inline]
init_data_container+0x49/0x1e0 fs/btrfs/backref.c:2779
btrfs_ioctl_logical_to_ino+0x17c/0x750 fs/btrfs/ioctl.c:3480
btrfs_ioctl+0x714/0x1260
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:904 [inline]
__se_sys_ioctl+0x261/0x450 fs/ioctl.c:890
__x64_sys_ioctl+0x96/0xe0 fs/ioctl.c:890
x64_sys_call+0x1883/0x3b50 arch/x86/include/generated/asm/syscalls_64.h:17
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Bytes 40-65535 of 65536 are uninitialized
Memory access of size 65536 starts at ffff888045a40000
This happens, because we're copying a 'struct btrfs_data_container' back
to user-space. This btrfs_data_container is allocated in
'init_data_container()' via kvmalloc(), which does not zero-fill the
memory.
Fix this by using kvzalloc() which zeroes out the memory on allocation.
CC: stable@vger.kernel.org # 4.14+
Reported-by: <syzbot+510a1abbb8116eeb341d@syzkaller.appspotmail.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Johannes Thumshirn <Johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The SLAB_MEM_SPREAD flag used to be implemented in SLAB, which was
removed as of v6.8-rc1, so it became a dead flag since the commit
16a1d96835 ("mm/slab: remove mm/slab.c and slab_def.h"). And the
series[1] went on to mark it obsolete to avoid confusion for users.
Here we can just remove all its users, which has no functional change.
[1] https://lore.kernel.org/all/20240223-slab-cleanup-flags-v2-1-02f1753e8303@suse.cz/
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There are many helpers doing simple things but not simple enough to
justify the static inline. None of them seems to be on a hot path so
move them to .c.
Signed-off-by: David Sterba <dsterba@suse.com>
The helper is trivial, we can inline it. It's safe to remove the 'if' as
the iterator is always valid when used, the potential NULL was never
checked anyway.
Signed-off-by: David Sterba <dsterba@suse.com>
Checking extent item size in add_inline_refs() is redundant, we do that
already in tree-checker after reading the extent buffer and it won't
change under normal circumstances. It was added long ago in
8da6d5815c ("Btrfs: added btrfs_find_all_roots()") and does not seem
to have a clear purpose.
Similar case in extent_from_logical(), added in a542ad1baf ("btrfs:
added helper functions to iterate backrefs").
Signed-off-by: David Sterba <dsterba@suse.com>
The extent_from_logical() helper looks up an extent item by a key,
allowing to do an inexact search when key->offset is -1. It's never
expected to find such item, as it would break the allowed range of a
extent item offset.
The same error is already handled in btrfs_backref_iter_start() so add a
comment for consistency.
Signed-off-by: David Sterba <dsterba@suse.com>
Same comment was added to this type of error, unify that and drop the
assertion as we'd find out quickly that something is wrong after
returning -EUCLEAN.
Signed-off-by: David Sterba <dsterba@suse.com>
-----BEGIN PGP SIGNATURE-----
iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAmU/xAEACgkQxWXV+ddt
WDvYKg//SjTimA5Nins9mb4jdz8n+dDeZnQhKzy3FqInU41EzDRc4WwnEODmDlTa
AyU9rGB3k0JNSUc075jZFCyLqq/ARiOqRi4x33Gk0ckIlc4X5OgBoqP2XkPh0VlP
txskLCrmhc3pwyR4ErlFDX2jebIUXfkv39bJuE40grGvUatRe+WNq0ERIrgO8RAr
Rc3hBotMH8AIqfD1L6j1ZiZIAyrOkT1BJMuqeoq27/gJZn/MRhM9TCrMTzfWGaoW
SxPrQiCDEN3KECsOY/caroMn3AekDijg/ley1Nf7Z0N6oEV+n4VWWPBFE9HhRz83
9fIdvSbGjSJF6ekzTjcVXPAbcuKZFzeqOdBRMIW3TIUo7mZQyJTVkMsc1y/NL2Z3
9DhlRLIzvWJJjt1CEK0u18n5IU+dGngdktbhWWIuIlo8r+G/iKR/7zqU92VfWLHL
Z7/eh6HgH5zr2bm+yKORbrUjkv4IVhGVarW8D4aM+MCG0lFN2GaPcJCCUrp4n7rZ
PzpQbxXa38ANBk6hsp4ndS8TJSBL9moY8tumzLcKg97nzNMV6KpBdV/G6/QfRLCN
3kM6UbwTAkMwGcQS86Mqx6s04ORLnQeD6f7N6X4Ppx0Mi/zkjI2HkRuvQGp12B0v
iZjCCZAYY2Iu+/TU0GrCXSss/grzIAUPzM9msyV3XGO/VBpwdec=
=9TVx
-----END PGP SIGNATURE-----
Merge tag 'for-6.7-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs updates from David Sterba:
"New features:
- raid-stripe-tree
New tree for logical file extent mapping where the physical mapping
may not match on multiple devices. This is now used in zoned mode
to implement RAID0/RAID1* profiles, but can be used in non-zoned
mode as well. The support for RAID56 is in development and will
eventually fix the problems with the current implementation. This
is a backward incompatible feature and has to be enabled at mkfs
time.
- simple quota accounting (squota)
A simplified mode of qgroup that accounts all space on the initial
extent owners (a subvolume), the snapshots are then cheap to create
and delete. The deletion of snapshots in fully accounting qgroups
is a known CPU/IO performance bottleneck.
The squota is not suitable for the general use case but works well
for containers where the original subvolume exists for the whole
time. This is a backward incompatible feature as it needs extending
some structures, but can be enabled on an existing filesystem.
- temporary filesystem fsid (temp_fsid)
The fsid identifies a filesystem and is hard coded in the
structures, which disallows mounting the same fsid found on
different devices.
For a single device filesystem this is not strictly necessary, a
new temporary fsid can be generated on mount e.g. after a device is
cloned. This will be used by Steam Deck for root partition A/B
testing, or can be used for VM root images.
Other user visible changes:
- filesystems with partially finished metadata_uuid conversion cannot
be mounted anymore and the uuid fixup has to be done by btrfs-progs
(btrfstune).
Performance improvements:
- reduce reservations for checksum deletions (with enabled free space
tree by factor of 4), on a sample workload on file with many
extents the deletion time decreased by 12%
- make extent state merges more efficient during insertions, reduce
rb-tree iterations (run time of critical functions reduced by 5%)
Core changes:
- the integrity check functionality has been removed, this was a
debugging feature and removal does not affect other integrity
checks like checksums or tree-checker
- space reservation changes:
- more efficient delayed ref reservations, this avoids building up
too much work or overusing or exhausting the global block
reserve in some situations
- move delayed refs reservation to the transaction start time,
this prevents some ENOSPC corner cases related to exhaustion of
global reserve
- improvements in reducing excessive reservations for block group
items
- adjust overcommit logic in near full situations, account for one
more chunk to eventually allocate metadata chunk, this is mostly
relevant for small filesystems (<10GiB)
- single device filesystems are scanned but not registered (except
seed devices), this allows temp_fsid to work
- qgroup iterations do not need GFP_ATOMIC allocations anymore
- cleanups, refactoring, reduced data structure size, function
parameter simplifications, error handling fixes"
* tag 'for-6.7-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (156 commits)
btrfs: open code timespec64 in struct btrfs_inode
btrfs: remove redundant log root tree index assignment during log sync
btrfs: remove redundant initialization of variable dirty in btrfs_update_time()
btrfs: sysfs: show temp_fsid feature
btrfs: disable the device add feature for temp-fsid
btrfs: disable the seed feature for temp-fsid
btrfs: update comment for temp-fsid, fsid, and metadata_uuid
btrfs: remove pointless empty log context list check when syncing log
btrfs: update comment for struct btrfs_inode::lock
btrfs: remove pointless barrier from btrfs_sync_file()
btrfs: add and use helpers for reading and writing last_trans_committed
btrfs: add and use helpers for reading and writing fs_info->generation
btrfs: add and use helpers for reading and writing log_transid
btrfs: add and use helpers for reading and writing last_log_commit
btrfs: support cloned-device mount capability
btrfs: add helper function find_fsid_by_disk
btrfs: stop reserving excessive space for block group item insertions
btrfs: stop reserving excessive space for block group item updates
btrfs: reorder btrfs_inode to fill gaps
btrfs: open code btrfs_ordered_inode_tree in btrfs_inode
...
When creating a snapshot of a subvolume that was created in the current
transaction, we can end up not persisting a dirty extent buffer that is
referenced by the snapshot, resulting in IO errors due to checksum failures
when trying to read the extent buffer later from disk. A sequence of steps
that leads to this is the following:
1) At ioctl.c:create_subvol() we allocate an extent buffer, with logical
address 36007936, for the leaf/root of a new subvolume that has an ID
of 291. We mark the extent buffer as dirty, and at this point the
subvolume tree has a single node/leaf which is also its root (level 0);
2) We no longer commit the transaction used to create the subvolume at
create_subvol(). We used to, but that was recently removed in
commit 1b53e51a4a ("btrfs: don't commit transaction for every subvol
create");
3) The transaction used to create the subvolume has an ID of 33, so the
extent buffer 36007936 has a generation of 33;
4) Several updates happen to subvolume 291 during transaction 33, several
files created and its tree height changes from 0 to 1, so we end up with
a new root at level 1 and the extent buffer 36007936 is now a leaf of
that new root node, which is extent buffer 36048896.
The commit root remains as 36007936, since we are still at transaction
33;
5) Creation of a snapshot of subvolume 291, with an ID of 292, starts at
ioctl.c:create_snapshot(). This triggers a commit of transaction 33 and
we end up at transaction.c:create_pending_snapshot(), in the critical
section of a transaction commit.
There we COW the root of subvolume 291, which is extent buffer 36048896.
The COW operation returns extent buffer 36048896, since there's no need
to COW because the extent buffer was created in this transaction and it
was not written yet.
The we call btrfs_copy_root() against the root node 36048896. During
this operation we allocate a new extent buffer to turn into the root
node of the snapshot, copy the contents of the root node 36048896 into
this snapshot root extent buffer, set the owner to 292 (the ID of the
snapshot), etc, and then we call btrfs_inc_ref(). This will create a
delayed reference for each leaf pointed by the root node with a
reference root of 292 - this includes a reference for the leaf
36007936.
After that we set the bit BTRFS_ROOT_FORCE_COW in the root's state.
Then we call btrfs_insert_dir_item(), to create the directory entry in
in the tree of subvolume 291 that points to the snapshot. This ends up
needing to modify leaf 36007936 to insert the respective directory
items. Because the bit BTRFS_ROOT_FORCE_COW is set for the root's state,
we need to COW the leaf. We end up at btrfs_force_cow_block() and then
at update_ref_for_cow().
At update_ref_for_cow() we call btrfs_block_can_be_shared() which
returns false, despite the fact the leaf 36007936 is shared - the
subvolume's root and the snapshot's root point to that leaf. The
reason that it incorrectly returns false is because the commit root
of the subvolume is extent buffer 36007936 - it was the initial root
of the subvolume when we created it. So btrfs_block_can_be_shared()
which has the following logic:
int btrfs_block_can_be_shared(struct btrfs_root *root,
struct extent_buffer *buf)
{
if (test_bit(BTRFS_ROOT_SHAREABLE, &root->state) &&
buf != root->node && buf != root->commit_root &&
(btrfs_header_generation(buf) <=
btrfs_root_last_snapshot(&root->root_item) ||
btrfs_header_flag(buf, BTRFS_HEADER_FLAG_RELOC)))
return 1;
return 0;
}
Returns false (0) since 'buf' (extent buffer 36007936) matches the
root's commit root.
As a result, at update_ref_for_cow(), we don't check for the number
of references for extent buffer 36007936, we just assume it's not
shared and therefore that it has only 1 reference, so we set the local
variable 'refs' to 1.
Later on, in the final if-else statement at update_ref_for_cow():
static noinline int update_ref_for_cow(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct extent_buffer *buf,
struct extent_buffer *cow,
int *last_ref)
{
(...)
if (refs > 1) {
(...)
} else {
(...)
btrfs_clear_buffer_dirty(trans, buf);
*last_ref = 1;
}
}
So we mark the extent buffer 36007936 as not dirty, and as a result
we don't write it to disk later in the transaction commit, despite the
fact that the snapshot's root points to it.
Attempting to access the leaf or dumping the tree for example shows
that the extent buffer was not written:
$ btrfs inspect-internal dump-tree -t 292 /dev/sdb
btrfs-progs v6.2.2
file tree key (292 ROOT_ITEM 33)
node 36110336 level 1 items 2 free space 119 generation 33 owner 292
node 36110336 flags 0x1(WRITTEN) backref revision 1
checksum stored a8103e3e
checksum calced a8103e3e
fs uuid 90c9a46f-ae9f-4626-9aff-0cbf3e2e3a79
chunk uuid e8c9c885-78f4-4d31-85fe-89e5f5fd4a07
key (256 INODE_ITEM 0) block 36007936 gen 33
key (257 EXTENT_DATA 0) block 36052992 gen 33
checksum verify failed on 36007936 wanted 0x00000000 found 0x86005f29
checksum verify failed on 36007936 wanted 0x00000000 found 0x86005f29
total bytes 107374182400
bytes used 38572032
uuid 90c9a46f-ae9f-4626-9aff-0cbf3e2e3a79
The respective on disk region is full of zeroes as the device was
trimmed at mkfs time.
Obviously 'btrfs check' also detects and complains about this:
$ btrfs check /dev/sdb
Opening filesystem to check...
Checking filesystem on /dev/sdb
UUID: 90c9a46f-ae9f-4626-9aff-0cbf3e2e3a79
generation: 33 (33)
[1/7] checking root items
[2/7] checking extents
checksum verify failed on 36007936 wanted 0x00000000 found 0x86005f29
checksum verify failed on 36007936 wanted 0x00000000 found 0x86005f29
checksum verify failed on 36007936 wanted 0x00000000 found 0x86005f29
bad tree block 36007936, bytenr mismatch, want=36007936, have=0
owner ref check failed [36007936 4096]
ERROR: errors found in extent allocation tree or chunk allocation
[3/7] checking free space tree
[4/7] checking fs roots
checksum verify failed on 36007936 wanted 0x00000000 found 0x86005f29
checksum verify failed on 36007936 wanted 0x00000000 found 0x86005f29
checksum verify failed on 36007936 wanted 0x00000000 found 0x86005f29
bad tree block 36007936, bytenr mismatch, want=36007936, have=0
The following tree block(s) is corrupted in tree 292:
tree block bytenr: 36110336, level: 1, node key: (256, 1, 0)
root 292 root dir 256 not found
ERROR: errors found in fs roots
found 38572032 bytes used, error(s) found
total csum bytes: 16048
total tree bytes: 1265664
total fs tree bytes: 1118208
total extent tree bytes: 65536
btree space waste bytes: 562598
file data blocks allocated: 65978368
referenced 36569088
Fix this by updating btrfs_block_can_be_shared() to consider that an
extent buffer may be shared if it matches the commit root and if its
generation matches the current transaction's generation.
This can be reproduced with the following script:
$ cat test.sh
#!/bin/bash
MNT=/mnt/sdi
DEV=/dev/sdi
# Use a filesystem with a 64K node size so that we have the same node
# size on every machine regardless of its page size (on x86_64 default
# node size is 16K due to the 4K page size, while on PPC it's 64K by
# default). This way we can make sure we are able to create a btree for
# the subvolume with a height of 2.
mkfs.btrfs -f -n 64K $DEV
mount $DEV $MNT
btrfs subvolume create $MNT/subvol
# Create a few empty files on the subvolume, this bumps its btree
# height to 2 (root node at level 1 and 2 leaves).
for ((i = 1; i <= 300; i++)); do
echo -n > $MNT/subvol/file_$i
done
btrfs subvolume snapshot -r $MNT/subvol $MNT/subvol/snap
umount $DEV
btrfs check $DEV
Running it on a 6.5 kernel (or any 6.6-rc kernel at the moment):
$ ./test.sh
Create subvolume '/mnt/sdi/subvol'
Create a readonly snapshot of '/mnt/sdi/subvol' in '/mnt/sdi/subvol/snap'
Opening filesystem to check...
Checking filesystem on /dev/sdi
UUID: bbdde2ff-7d02-45ca-8a73-3c36f23755a1
[1/7] checking root items
[2/7] checking extents
parent transid verify failed on 30539776 wanted 7 found 5
parent transid verify failed on 30539776 wanted 7 found 5
parent transid verify failed on 30539776 wanted 7 found 5
Ignoring transid failure
owner ref check failed [30539776 65536]
ERROR: errors found in extent allocation tree or chunk allocation
[3/7] checking free space tree
[4/7] checking fs roots
parent transid verify failed on 30539776 wanted 7 found 5
Ignoring transid failure
Wrong key of child node/leaf, wanted: (256, 1, 0), have: (2, 132, 0)
Wrong generation of child node/leaf, wanted: 5, have: 7
root 257 root dir 256 not found
ERROR: errors found in fs roots
found 917504 bytes used, error(s) found
total csum bytes: 0
total tree bytes: 851968
total fs tree bytes: 393216
total extent tree bytes: 65536
btree space waste bytes: 736550
file data blocks allocated: 0
referenced 0
A test case for fstests will follow soon.
Fixes: 1b53e51a4a ("btrfs: don't commit transaction for every subvol create")
CC: stable@vger.kernel.org # 6.5+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The btrfs_backref_cache::is_reloc is an indicator variable and should
use a bool type.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In order to implement simple quota groups, we need to be able to
associate a data extent with the subvolume that created it. Once you
account for reflink, this information cannot be recovered without
explicitly storing it. Options for storing it are:
- a new key/item
- a new extent inline ref item
The former is backwards compatible, but wastes space, the latter is
incompat, but is efficient in space and reuses the existing inline ref
machinery, while only abusing it a tiny amount -- specifically, the new
item is not a ref, per-se.
Signed-off-by: Boris Burkov <boris@bur.io>
Signed-off-by: David Sterba <dsterba@suse.com>
