Pull ext4 updates from Ted Ts'o:
- Refactor code paths involved with partial block zero-out in
prearation for converting ext4 to use iomap for buffered writes
- Remove use of d_alloc() from ext4 in preparation for the deprecation
of this interface
- Replace some J_ASSERTS with a journal abort so we can avoid a kernel
panic for a localized file system error
- Simplify various code paths in mballoc, move_extent, and fast commit
- Fix rare deadlock in jbd2_journal_cancel_revoke() that can be
triggered by generic/013 when blocksize < pagesize
- Fix memory leak when releasing an extended attribute when its value
is stored in an ea_inode
- Fix various potential kunit test bugs in fs/ext4/extents.c
- Fix potential out-of-bounds access in check_xattr() with a corrupted
file system
- Make the jbd2_inode dirty range tracking safe for lockless reads
- Avoid a WARN_ON when writeback files due to a corrupted file system;
we already print an ext4 warning indicatign that data will be lost,
so the WARN_ON is not necessary and doesn't add any new information
* tag 'ext4_for_linux-7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (37 commits)
jbd2: fix deadlock in jbd2_journal_cancel_revoke()
ext4: fix missing brelse() in ext4_xattr_inode_dec_ref_all()
ext4: fix possible null-ptr-deref in mbt_kunit_exit()
ext4: fix possible null-ptr-deref in extents_kunit_exit()
ext4: fix the error handling process in extents_kunit_init).
ext4: call deactivate_super() in extents_kunit_exit()
ext4: fix miss unlock 'sb->s_umount' in extents_kunit_init()
ext4: fix bounds check in check_xattrs() to prevent out-of-bounds access
ext4: zero post-EOF partial block before appending write
ext4: move pagecache_isize_extended() out of active handle
ext4: remove ctime/mtime update from ext4_alloc_file_blocks()
ext4: unify SYNC mode checks in fallocate paths
ext4: ensure zeroed partial blocks are persisted in SYNC mode
ext4: move zero partial block range functions out of active handle
ext4: pass allocate range as loff_t to ext4_alloc_file_blocks()
ext4: remove handle parameters from zero partial block functions
ext4: move ordered data handling out of ext4_block_do_zero_range()
ext4: rename ext4_block_zero_page_range() to ext4_block_zero_range()
ext4: factor out journalled block zeroing range
ext4: rename and extend ext4_block_truncate_page()
...
Pull vfs buffer_head updates from Christian Brauner:
"This cleans up the mess that has accumulated over the years in
metadata buffer_head tracking for inodes.
It moves the tracking into dedicated structure in filesystem-private
part of the inode (so that we don't use private_list, private_data,
and private_lock in struct address_space), and also moves couple other
users of private_data and private_list so these are removed from
struct address_space saving 3 longs in struct inode for 99% of inodes"
* tag 'vfs-7.1-rc1.bh.metadata' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (42 commits)
fs: Drop i_private_list from address_space
fs: Drop mapping_metadata_bhs from address space
ext4: Track metadata bhs in fs-private inode part
minix: Track metadata bhs in fs-private inode part
udf: Track metadata bhs in fs-private inode part
fat: Track metadata bhs in fs-private inode part
bfs: Track metadata bhs in fs-private inode part
affs: Track metadata bhs in fs-private inode part
ext2: Track metadata bhs in fs-private inode part
fs: Provide functions for handling mapping_metadata_bhs directly
fs: Switch inode_has_buffers() to take mapping_metadata_bhs
fs: Make bhs point to mapping_metadata_bhs
fs: Move metadata bhs tracking to a separate struct
fs: Fold fsync_buffers_list() into sync_mapping_buffers()
fs: Drop osync_buffers_list()
kvm: Use private inode list instead of i_private_list
fs: Remove i_private_data
aio: Stop using i_private_data and i_private_lock
hugetlbfs: Stop using i_private_data
fs: Stop using i_private_data for metadata bh tracking
...
Pull vfs i_ino updates from Christian Brauner:
"For historical reasons, the inode->i_ino field is an unsigned long,
which means that it's 32 bits on 32 bit architectures. This has caused
a number of filesystems to implement hacks to hash a 64-bit identifier
into a 32-bit field, and deprives us of a universal identifier field
for an inode.
This changes the inode->i_ino field from an unsigned long to a u64.
This shouldn't make any material difference on 64-bit hosts, but
32-bit hosts will see struct inode grow by at least 4 bytes. This
could have effects on slabcache sizes and field alignment.
The bulk of the changes are to format strings and tracepoints, since
the kernel itself doesn't care that much about the i_ino field. The
first patch changes some vfs function arguments, so check that one out
carefully.
With this change, we may be able to shrink some inode structures. For
instance, struct nfs_inode has a fileid field that holds the 64-bit
inode number. With this set of changes, that field could be
eliminated. I'd rather leave that sort of cleanups for later just to
keep this simple"
* tag 'vfs-7.1-rc1.kino' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
nilfs2: fix 64-bit division operations in nilfs_bmap_find_target_in_group()
EVM: add comment describing why ino field is still unsigned long
vfs: remove externs from fs.h on functions modified by i_ino widening
treewide: fix missed i_ino format specifier conversions
ext4: fix signed format specifier in ext4_load_inode trace event
treewide: change inode->i_ino from unsigned long to u64
nilfs2: widen trace event i_ino fields to u64
f2fs: widen trace event i_ino fields to u64
ext4: widen trace event i_ino fields to u64
zonefs: widen trace event i_ino fields to u64
hugetlbfs: widen trace event i_ino fields to u64
ext2: widen trace event i_ino fields to u64
cachefiles: widen trace event i_ino fields to u64
vfs: widen trace event i_ino fields to u64
net: change sock.sk_ino and sock_i_ino() to u64
audit: widen ino fields to u64
vfs: widen inode hash/lookup functions to u64
In ext4_zero_range() and ext4_punch_hole(), when operating in SYNC mode
and zeroing a partial block, only data=journal modes guarantee that the
zeroed data is synchronously persisted after the operation completes.
For data=ordered/writeback mode and non-journal modes, this guarantee is
missing.
Introduce a partial_zero parameter to explicitly trigger writeback for
all scenarios where a partial block is zeroed, ensuring the zeroed data
is durably persisted.
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://patch.msgid.link/20260327102939.1095257-10-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Only journal data mode requires an active journal handle when zeroing
partial blocks. Stop passing handle_t *handle to
ext4_zero_partial_blocks() and related functions, and make
ext4_block_journalled_zero_range() start a handle independently.
This change has no practical impact now because all callers invoke these
functions within the context of an active handle. It prepares for moving
ext4_block_zero_eof() out of an active handle in the next patch, which
is a prerequisite for converting block zero range operations to iomap
infrastructure.
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260327102939.1095257-7-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Rename ext4_block_truncate_page() to ext4_block_zero_eof() and extend
its signature to accept an explicit 'end' offset instead of calculating
the block boundary. This helper function now can replace all cases
requiring zeroing of the partial EOF block, including the append
buffered write paths in ext4_*_write_end().
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260327102939.1095257-3-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
__ext4_link() has two callers.
- ext4_link() calls it during normal handling of the link() system
call or similar
- ext4_fc_replay_link_internal() calls it when replaying the journal
at mount time.
The former needs changes to dcache - instantiating the dentry to the
inode on success. The latter doesn't need or want any dcache
manipulation.
So move the manipulation out of __ext4_link() and do it in ext4_link()
only.
This requires:
- passing the qname from the dentry explicitly to __ext4_link.
The parent dir is already passed. The dentry is still passed
in the ext4_link() case purely for use by ext4_fc_track_link().
- passing the inode separately to ext4_fc_track_link() as the
dentry will not be instantiated yet.
- using __ext4_add_entry() in ext4_link, which doesn't need a dentry.
- moving ihold(), d_instantiate(), drop_nlink() and iput() calls out
of __ext4_link() into ext4_link().
Note that ext4_inc_count() and drop_nlink() remain in __ext4_link()
as both callers need them and they are not related to the dentry.
This substantially simplifies ext4_fc_replay_link_internal(), and
removes a use of d_alloc() which, it is planned, will be removed.
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: NeilBrown <neil@brown.name>
Link: https://patch.msgid.link/20260320000838.3797494-4-neilb@ownmail.net
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Commit b98535d091 ("ext4: fix bug_on in start_this_handle during umount
filesystem") moved ext4_unregister_sysfs() before flushing s_sb_upd_work
to prevent new error work from being queued via /proc/fs/ext4/xx/mb_groups
reads during unmount. However, this introduced a use-after-free because
update_super_work calls ext4_notify_error_sysfs() -> sysfs_notify() which
accesses the kobject's kernfs_node after it has been freed by kobject_del()
in ext4_unregister_sysfs():
update_super_work ext4_put_super
----------------- --------------
ext4_unregister_sysfs(sb)
kobject_del(&sbi->s_kobj)
__kobject_del()
sysfs_remove_dir()
kobj->sd = NULL
sysfs_put(sd)
kernfs_put() // RCU free
ext4_notify_error_sysfs(sbi)
sysfs_notify(&sbi->s_kobj)
kn = kobj->sd // stale pointer
kernfs_get(kn) // UAF on freed kernfs_node
ext4_journal_destroy()
flush_work(&sbi->s_sb_upd_work)
Instead of reordering the teardown sequence, fix this by making
ext4_notify_error_sysfs() detect that sysfs has already been torn down
by checking s_kobj.state_in_sysfs, and skipping the sysfs_notify() call
in that case. A dedicated mutex (s_error_notify_mutex) serializes
ext4_notify_error_sysfs() against kobject_del() in ext4_unregister_sysfs()
to prevent TOCTOU races where the kobject could be deleted between the
state_in_sysfs check and the sysfs_notify() call.
Fixes: b98535d091 ("ext4: fix bug_on in start_this_handle during umount filesystem")
Cc: Jiayuan Chen <jiayuan.chen@linux.dev>
Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jiayuan Chen <jiayuan.chen@shopee.com>
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260319120336.157873-1-jiayuan.chen@linux.dev
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Track metadata bhs for an inode in fs-private part of the inode. We need
the tracking only for nojournal mode so this is somewhat wasteful. We
can relatively easily make the mapping_metadata_bhs struct dynamically
allocated similarly to how we treat jbd2_inode but let's leave that for
ext4 specific series once the dust settles a bit.
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260326095354.16340-82-jack@suse.cz
Signed-off-by: Christian Brauner <brauner@kernel.org>
On 32-bit architectures, unsigned long is only 32 bits wide, which
causes 64-bit inode numbers to be silently truncated. Several
filesystems (NFS, XFS, BTRFS, etc.) can generate inode numbers that
exceed 32 bits, and this truncation can lead to inode number collisions
and other subtle bugs on 32-bit systems.
Change the type of inode->i_ino from unsigned long to u64 to ensure that
inode numbers are always represented as 64-bit values regardless of
architecture. Update all format specifiers treewide from %lu/%lx to
%llu/%llx to match the new type, along with corresponding local variable
types.
This is the bulk treewide conversion. Earlier patches in this series
handled trace events separately to allow trace field reordering for
better struct packing on 32-bit.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Link: https://patch.msgid.link/20260304-iino-u64-v3-12-2257ad83d372@kernel.org
Acked-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Pull fsverity updates from Eric Biggers:
"fsverity cleanups, speedup, and memory usage optimization from
Christoph Hellwig:
- Move some logic into common code
- Fix btrfs to reject truncates of fsverity files
- Improve the readahead implementation
- Store each inode's fsverity_info in a hash table instead of using a
pointer in the filesystem-specific part of the inode.
This optimizes for memory usage in the usual case where most files
don't have fsverity enabled.
- Look up the fsverity_info fewer times during verification, to
amortize the hash table overhead"
* tag 'fsverity-for-linus' of git://git.kernel.org/pub/scm/fs/fsverity/linux:
fsverity: remove inode from fsverity_verification_ctx
fsverity: use a hashtable to find the fsverity_info
btrfs: consolidate fsverity_info lookup
f2fs: consolidate fsverity_info lookup
ext4: consolidate fsverity_info lookup
fs: consolidate fsverity_info lookup in buffer.c
fsverity: push out fsverity_info lookup
fsverity: deconstify the inode pointer in struct fsverity_info
fsverity: kick off hash readahead at data I/O submission time
ext4: move ->read_folio and ->readahead to readpage.c
readahead: push invalidate_lock out of page_cache_ra_unbounded
fsverity: don't issue readahead for non-ENOENT errors from __filemap_get_folio
fsverity: start consolidating pagecache code
fsverity: pass struct file to ->write_merkle_tree_block
f2fs: don't build the fsverity work handler for !CONFIG_FS_VERITY
ext4: don't build the fsverity work handler for !CONFIG_FS_VERITY
fs,fsverity: clear out fsverity_info from common code
fs,fsverity: reject size changes on fsverity files in setattr_prepare
Pull ext4 updates from Ted Ts'o:
"New features and improvements for the ext4 file system
- Avoid unnecessary cache invalidation in the extent status cache
(es_cache) when adding extents to be cached in the es_cache and we
are not changing the extent tree
- Add a sysfs parameter, err_report_sec, to control how frequently to
log a warning message that file system inconsistency has been
detected (Previously we logged the warning message every 24 hours)
- Avoid unnecessary forced ordered writes when appending to a file
when delayed allocation is enabled
- Defer splitting unwritten extents to I/O completion to improve
write performance of concurrent direct I/O writes to multiple files
- Refactor and add kunit tests to the extent splitting and conversion
code paths
Various Bug Fixes:
- Fix a panic when the debugging DOUBLE_CHECK macro is defined
- Avoid using fast commit for rare and complex file system operations
to make fast commit easier to reason about. This can also avoid
some corner cases that could result in file system inconsistency if
there is a crash between the fast commit before a subsequent full
commit
- Fix memory leaks in error paths
- Fix a false positive reports caused when running stress tests using
mixed huge-page workloads caused by a race between page migration
and bitmap updates
- Fix a potential recursion into file system reclaim when evicting an
inode when fast commit is enabled
- Fix a warning caused by a potential double decrement to the dirty
clusters counter when executing FS_IOC_SHUTDOWN when running a
stress test
- Enable mballoc optimized scanning regardless whether the inode is
using indirect blocks or extent trees to map blocks"
* tag 'ext4_for_linus-7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (45 commits)
et4: allow zeroout when doing written to unwritten split
ext4: refactor split and convert extents
ext4: refactor zeroout path and handle all cases
ext4: propagate flags to ext4_convert_unwritten_extents_endio()
ext4: propagate flags to convert_initialized_extent()
ext4: add extent status cache support to kunit tests
ext4: kunit tests for higher level extent manipulation functions
ext4: kunit tests for extent splitting and conversion
ext4: use optimized mballoc scanning regardless of inode format
ext4: always allocate blocks only from groups inode can use
ext4: fix dirtyclusters double decrement on fs shutdown
ext4: fast commit: make s_fc_lock reclaim-safe
ext4: fix e4b bitmap inconsistency reports
ext4: remove redundant NULL check after __GFP_NOFAIL
ext4: remove EXT4_GET_BLOCKS_IO_CREATE_EXT
ext4: simplify the mapping query logic in ext4_iomap_begin()
ext4: remove unused unwritten parameter in ext4_dio_write_iter()
ext4: remove useless ext4_iomap_overwrite_ops
ext4: avoid starting handle when dio writing an unwritten extent
ext4: don't split extent before submitting I/O
...
Use the kernel's resizable hash table (rhashtable) to find the
fsverity_info. This way file systems that want to support fsverity don't
have to bloat every inode in the system with an extra pointer. The
trade-off is that looking up the fsverity_info is a bit more expensive
now, but the main operations are still dominated by I/O and hashing
overhead.
The rhashtable implementations requires no external synchronization, and
the _fast versions of the APIs provide the RCU critical sections required
by the implementation. Because struct fsverity_info is only removed on
inode eviction and does not contain a reference count, there is no need
for an extended critical section to grab a reference or validate the
object state. The file open path uses rhashtable_lookup_get_insert_fast,
which can either find an existing object for the hash key or insert a
new one in a single atomic operation, so that concurrent opens never
instantiate duplicate fsverity_info structure. FS_IOC_ENABLE_VERITY must
already be synchronized by a combination of i_rwsem and file system flags
and uses rhashtable_lookup_insert_fast, which errors out on an existing
object for the hash key as an additional safety check.
Because insertion into the hash table now happens before S_VERITY is set,
fsverity just becomes a barrier and a flag check and doesn't have to look
up the fsverity_info at all, so there is only a single lookup per
->read_folio or ->readahead invocation. For btrfs there is an additional
one for each bio completion, while for ext4 and f2fs the fsverity_info
is stored in the per-I/O context and reused for the completion workqueue.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Link: https://lore.kernel.org/r/20260202060754.270269-12-hch@lst.de
[EB: folded in fix for missing fsverity_free_info()]
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Add more kunit tests to cover the high level caller
ext4_map_create_blocks(). We pass flags in a manner that covers
the below function:
1. ext4_ext_handle_unwritten_extents()
1.1 - Split/Convert unwritten extent to written in endio convtext.
1.2 - Split/Convert unwritten extent to written in non endio context.
1.3 - Zeroout tests for the above 2 cases
2. convert_initialized_extent() - Convert written extent to unwritten
during zero range
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Link: https://patch.msgid.link/9d8ad32cb62f44999c0fe3545b44fc3113546c70.1769149131.git.ojaswin@linux.ibm.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
s_fc_lock can be acquired from inode eviction and thus is
reclaim unsafe. Since the fast commit path holds s_fc_lock while writing
the commit log, allocations under the lock can enter reclaim and invert
the lock order with fs_reclaim. Add ext4_fc_lock()/ext4_fc_unlock()
helpers which acquire s_fc_lock under memalloc_nofs_save()/restore()
context and use them everywhere so allocations under the lock cannot
recurse into filesystem reclaim.
Fixes: 6593714d67 ("ext4: hold s_fc_lock while during fast commit")
Signed-off-by: Li Chen <me@linux.beauty>
Reviewed-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260106120621.440126-1-me@linux.beauty
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
ext4_iomap_overwrite_ops was introduced in commit 8cd115bdda ("ext4:
Optimize ext4 DIO overwrites"), which can optimize pure overwrite
performance by dropping the IOMAP_WRITE flag to only query the mapped
mapping information. This avoids starting a new journal handle, thereby
improving speed. Later, commit 9faac62d40 ("ext4: optimize file
overwrites") also optimized similar scenarios, but it performs the check
later, examining the mappings status only when the actual block mapping
is needed. Thus, it can handle the previous commit scenario. That means
in the case of an overwrite scenario, the condition
"offset + length <= i_size_read(inode)" in the write path must always be
true.
Therefore, it is acceptable to remove the ext4_iomap_overwrite_ops,
which will also clarify the write and read paths of ext4_iomap_begin.
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Link: https://patch.msgid.link/20260105014522.1937690-5-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Supporting a block size greater than the page size (BS > PS) requires
support for large folios. However, several features (e.g., encrypt)
do not yet support large folios.
To prevent conflicts, this patch adds checks at mount time to prohibit
these features from being used when BS > PS. Since these features cannot
be changed on remount, there is no need to check on remount.
This patch adds s_max_folio_order, initialized during mount according to
filesystem features and mount options. If s_max_folio_order is 0, large
folios are disabled.
With this in place, ext4_set_inode_mapping_order() can be simplified by
checking s_max_folio_order, avoiding redundant checks.
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Message-ID: <20251121090654.631996-24-libaokun@huaweicloud.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Previously, ext4_rec_len_(to|from)_disk only performed complex rec_len
conversions when PAGE_SIZE >= 65536 to reduce complexity.
However, we are soon to support file system block sizes greater than
page size, which makes these conditional checks unnecessary. Thus, these
checks are now removed.
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Message-ID: <20251121090654.631996-4-libaokun@huaweicloud.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
When creating or querying mapping blocks using the ext4_map_blocks() and
ext4_map_{query|create}_blocks() helpers, also pass out the extent
sequence number of the block mapping info through the ext4_map_blocks
structure. This sequence number can later serve as a valid cookie within
iomap infrastructure and the move extents procedure.
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-ID: <20251013015128.499308-5-yi.zhang@huaweicloud.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
In the iomap_write_iter(), the iomap buffered write frame does not hold
any locks between querying the inode extent mapping info and performing
page cache writes. As a result, the extent mapping can be changed due to
concurrent I/O in flight. Similarly, in the iomap_writepage_map(), the
write-back process faces a similar problem: concurrent changes can
invalidate the extent mapping before the I/O is submitted.
Therefore, both of these processes must recheck the mapping info after
acquiring the folio lock. To address this, similar to XFS, we propose
introducing an extent sequence number to serve as a validity cookie for
the extent. After commit 24b7a2331f ("ext4: clairfy the rules for
modifying extents"), we can ensure the extent information should always
be processed through the extent status tree, and the extent status tree
is always uptodate under i_rwsem or invalidate_lock or folio lock, so
it's safe to introduce this sequence number. The sequence number will be
increased whenever the extent status tree changes, preparing for the
buffered write iomap conversion.
Besides, this mechanism is also applicable for the moving extents case.
In move_extent_per_page(), it also needs to reacquire data_sem and check
the mapping info again under the folio lock.
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-ID: <20251013015128.499308-3-yi.zhang@huaweicloud.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Pull ext4 updates from Ted Ts'o:
"New ext4 features:
- Add support so tune2fs can modify/update the superblock using an
ioctl, without needing write access to the block device
- Add support for 32-bit reserved uid's and gid's
Bug fixes:
- Fix potential warnings and other failures caused by corrupted /
fuzzed file systems
- Fail unaligned direct I/O write with EINVAL instead of silently
falling back to buffered I/O
- Correectly handle fsmap queries for metadata mappings
- Avoid journal stalls caused by writeback throttling
- Add some missing GFP_NOFAIL flags to avoid potential deadlocks
under extremem memory pressure
Cleanups:
- Remove obsolete EXT3 Kconfigs"
* tag 'ext4_for_linus-6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: fix checks for orphan inodes
ext4: validate ea_ino and size in check_xattrs
ext4: guard against EA inode refcount underflow in xattr update
ext4: implemet new ioctls to set and get superblock parameters
ext4: add support for 32-bit default reserved uid and gid values
ext4: avoid potential buffer over-read in parse_apply_sb_mount_options()
ext4: fix an off-by-one issue during moving extents
ext4: increase i_disksize to offset + len in ext4_update_disksize_before_punch()
ext4: verify orphan file size is not too big
ext4: fail unaligned direct IO write with EINVAL
ext4: correctly handle queries for metadata mappings
ext4: increase IO priority of fastcommit
ext4: remove obsolete EXT3 config options
jbd2: increase IO priority of checkpoint
ext4: fix potential null deref in ext4_mb_init()
ext4: add ext4_sb_bread_nofail() helper function for ext4_free_branches()
ext4: replace min/max nesting with clamp()
fs: ext4: change GFP_KERNEL to GFP_NOFS to avoid deadlock
When orphan file feature is enabled, inode can be tracked as orphan
either in the standard orphan list or in the orphan file. The first can
be tested by checking ei->i_orphan list head, the second is recorded by
EXT4_STATE_ORPHAN_FILE inode state flag. There are several places where
we want to check whether inode is tracked as orphan and only some of
them properly check for both possibilities. Luckily the consequences are
mostly minor, the worst that can happen is that we track an inode as
orphan although we don't need to and e2fsck then complains (resulting in
occasional ext4/307 xfstest failures). Fix the problem by introducing a
helper for checking whether an inode is tracked as orphan and use it in
appropriate places.
Fixes: 4a79a98c7b ("ext4: Improve scalability of ext4 orphan file handling")
Cc: stable@kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Message-ID: <20250925123038.20264-2-jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Support for specifying the default user id and group id that is
allowed to use the reserved block space was added way back when Linux
only supported 16-bit uid's and gid's. (Yeah, that long ago.) It's
not a commonly used feature, but let's add support for 32-bit user and
group id's.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Message-ID: <20250916-tune2fs-v2-2-d594dc7486f0@mit.edu>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
The implicit __GFP_NOFAIL flag in ext4_sb_bread() was removed in commit
8a83ac5494 ("ext4: call bdev_getblk() from sb_getblk_gfp()"), meaning
the function can now fail under memory pressure.
Most callers of ext4_sb_bread() propagate the error to userspace and do not
remount the filesystem read-only. However, ext4_free_branches() handles
ext4_sb_bread() failure by remounting the filesystem read-only.
This implies that an ext3 filesystem (mounted via the ext4 driver) could be
forcibly remounted read-only due to a transient page allocation failure,
which is unacceptable.
To mitigate this, introduce a new helper function, ext4_sb_bread_nofail(),
which explicitly uses __GFP_NOFAIL, and use it in ext4_free_branches().
Fixes: 8a83ac5494 ("ext4: call bdev_getblk() from sb_getblk_gfp()")
Cc: stable@kernel.org
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Move the fsverity_info pointer into the filesystem-specific part of the
inode by adding the field ext4_inode_info::i_verity_info and configuring
fsverity_operations::inode_info_offs accordingly.
This is a prerequisite for a later commit that removes
inode::i_verity_info, saving memory and improving cache efficiency on
filesystems that don't support fsverity.
Co-developed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Link: https://lore.kernel.org/20250810075706.172910-10-ebiggers@kernel.org
Acked-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Move the fscrypt_inode_info pointer into the filesystem-specific part of
the inode by adding the field ext4_inode_info::i_crypt_info and
configuring fscrypt_operations::inode_info_offs accordingly.
This is a prerequisite for a later commit that removes
inode::i_crypt_info, saving memory and improving cache efficiency with
filesystems that don't support fscrypt.
Co-developed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Link: https://lore.kernel.org/20250810075706.172910-4-ebiggers@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Pull ext4 updates from Ted Ts'o:
"Major ext4 changes for 6.17:
- Better scalability for ext4 block allocation
- Fix insufficient credits when writing back large folios
Miscellaneous bug fixes, especially when handling exteded attriutes,
inline data, and fast commit"
* tag 'ext4_for_linus_6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (39 commits)
ext4: do not BUG when INLINE_DATA_FL lacks system.data xattr
ext4: implement linear-like traversal across order xarrays
ext4: refactor choose group to scan group
ext4: convert free groups order lists to xarrays
ext4: factor out ext4_mb_scan_group()
ext4: factor out ext4_mb_might_prefetch()
ext4: factor out __ext4_mb_scan_group()
ext4: fix largest free orders lists corruption on mb_optimize_scan switch
ext4: fix zombie groups in average fragment size lists
ext4: merge freed extent with existing extents before insertion
ext4: convert sbi->s_mb_free_pending to atomic_t
ext4: fix typo in CR_GOAL_LEN_SLOW comment
ext4: get rid of some obsolete EXT4_MB_HINT flags
ext4: utilize multiple global goals to reduce contention
ext4: remove unnecessary s_md_lock on update s_mb_last_group
ext4: remove unnecessary s_mb_last_start
ext4: separate stream goal hits from s_bal_goals for better tracking
ext4: add ext4_try_lock_group() to skip busy groups
ext4: initialize superblock fields in the kballoc-test.c kunit tests
ext4: refactor the inline directory conversion and new directory codepaths
...
This commit converts the `choose group` logic to `scan group` using
previously prepared helper functions. This allows us to leverage xarrays
for ordered non-linear traversal, thereby mitigating the "bouncing" issue
inherent in the `choose group` mechanism.
This also decouples linear and non-linear traversals, leading to cleaner
and more readable code.
Key changes:
* ext4_mb_choose_next_group() is refactored to ext4_mb_scan_groups().
* Replaced ext4_mb_good_group() with ext4_mb_scan_group() in non-linear
traversals, and related functions now return error codes instead of
group info.
* Added ext4_mb_scan_groups_linear() for performing linear scans starting
from a specific group for a set number of times.
* Linear scans now execute up to sbi->s_mb_max_linear_groups times,
so ac_groups_linear_remaining is removed as it's no longer used.
* ac->ac_criteria is now used directly instead of passing cr around.
Also, ac->ac_criteria is incremented directly after groups scan fails
for the corresponding criteria.
* Since we're now directly scanning groups instead of finding a good group
then scanning, the following variables and flags are no longer needed,
s_bal_cX_groups_considered is sufficient.
s_bal_p2_aligned_bad_suggestions
s_bal_goal_fast_bad_suggestions
s_bal_best_avail_bad_suggestions
EXT4_MB_CR_POWER2_ALIGNED_OPTIMIZED
EXT4_MB_CR_GOAL_LEN_FAST_OPTIMIZED
EXT4_MB_CR_BEST_AVAIL_LEN_OPTIMIZED
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://patch.msgid.link/20250714130327.1830534-17-libaokun1@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
While traversing the list, holding a spin_lock prevents load_buddy, making
direct use of ext4_try_lock_group impossible. This can lead to a bouncing
scenario where spin_is_locked(grp_A) succeeds, but ext4_try_lock_group()
fails, forcing the list traversal to repeatedly restart from grp_A.
In contrast, linear traversal directly uses ext4_try_lock_group(),
avoiding this bouncing. Therefore, we need a lockless, ordered traversal
to achieve linear-like efficiency.
Therefore, this commit converts both average fragment size lists and
largest free order lists into ordered xarrays.
In an xarray, the index represents the block group number and the value
holds the block group information; a non-empty value indicates the block
group's presence.
While insertion and deletion complexity remain O(1), lookup complexity
changes from O(1) to O(nlogn), which may slightly reduce single-threaded
performance.
Additionally, xarray insertions might fail, potentially due to memory
allocation issues. However, since we have linear traversal as a fallback,
this isn't a major problem. Therefore, we've only added a warning message
for insertion failures here.
A helper function ext4_mb_find_good_group_xarray() is added to find good
groups in the specified xarray starting at the specified position start,
and when it reaches ngroups-1, it wraps around to 0 and then to start-1.
This ensures an ordered traversal within the xarray.
Performance test results are as follows: Single-process operations
on an empty disk show negligible impact, while multi-process workloads
demonstrate a noticeable performance gain.
|CPU: Kunpeng 920 | P80 | P1 |
|Memory: 512GB |------------------------|-------------------------|
|960GB SSD (0.5GB/s)| base | patched | base | patched |
|-------------------|-------|----------------|--------|----------------|
|mb_optimize_scan=0 | 20097 | 19555 (-2.6%) | 316141 | 315636 (-0.2%) |
|mb_optimize_scan=1 | 13318 | 15496 (+16.3%) | 325273 | 323569 (-0.5%) |
|CPU: AMD 9654 * 2 | P96 | P1 |
|Memory: 1536GB |------------------------|-------------------------|
|960GB SSD (1GB/s) | base | patched | base | patched |
|-------------------|-------|----------------|--------|----------------|
|mb_optimize_scan=0 | 53603 | 53192 (-0.7%) | 214243 | 212678 (-0.7%) |
|mb_optimize_scan=1 | 20887 | 37636 (+80.1%) | 213632 | 214189 (+0.2%) |
[ Applied spelling fixes per discussion on the ext4-list see thread
referened in the Link tag. --tytso]
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://patch.msgid.link/20250714130327.1830534-16-libaokun1@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Previously, s_md_lock was used to protect s_mb_free_pending during
modifications, while smp_mb() ensured fresh reads, so s_md_lock just
guarantees the atomicity of s_mb_free_pending. Thus we optimized it by
converting s_mb_free_pending into an atomic variable, thereby eliminating
s_md_lock and minimizing lock contention. This also prepares for future
lockless merging of free extents.
Following this modification, s_md_lock is exclusively responsible for
managing insertions and deletions within s_freed_data_list, along with
operations involving list_splice.
Performance test data follows:
Test: Running will-it-scale/fallocate2 on CPU-bound containers.
Observation: Average fallocate operations per container per second.
|CPU: Kunpeng 920 | P80 | P1 |
|Memory: 512GB |------------------------|-------------------------|
|960GB SSD (0.5GB/s)| base | patched | base | patched |
|-------------------|-------|----------------|--------|----------------|
|mb_optimize_scan=0 | 19628 | 20043 (+2.1%) | 320885 | 314331 (-2.0%) |
|mb_optimize_scan=1 | 7129 | 7290 (+2.2%) | 321275 | 324226 (+0.9%) |
|CPU: AMD 9654 * 2 | P96 | P1 |
|Memory: 1536GB |------------------------|-------------------------|
|960GB SSD (1GB/s) | base | patched | base | patched |
|-------------------|-------|----------------|--------|----------------|
|mb_optimize_scan=0 | 53760 | 54999 (+2.3%) | 213145 | 214380 (+0.5%) |
|mb_optimize_scan=1 | 12716 | 13497 (+6.1%) | 215262 | 216276 (+0.4%) |
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://patch.msgid.link/20250714130327.1830534-9-libaokun1@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
When allocating data blocks, if the first try (goal allocation) fails and
stream allocation is on, it tries a global goal starting from the last
group we used (s_mb_last_group). This helps cluster large files together
to reduce free space fragmentation, and the data block contiguity also
accelerates write-back to disk.
However, when multiple processes allocate blocks, having just one global
goal means they all fight over the same group. This drastically lowers
the chances of extents merging and leads to much worse file fragmentation.
To mitigate this multi-process contention, we now employ multiple global
goals, with the number of goals being the minimum between the number of
possible CPUs and one-quarter of the filesystem's total block group count.
To ensure a consistent goal for each inode, we select the corresponding
goal by taking the inode number modulo the total number of goals.
Performance test data follows:
Test: Running will-it-scale/fallocate2 on CPU-bound containers.
Observation: Average fallocate operations per container per second.
|CPU: Kunpeng 920 | P80 | P1 |
|Memory: 512GB |------------------------|-------------------------|
|960GB SSD (0.5GB/s)| base | patched | base | patched |
|-------------------|-------|----------------|--------|----------------|
|mb_optimize_scan=0 | 9636 | 19628 (+103%) | 337597 | 320885 (-4.9%) |
|mb_optimize_scan=1 | 4834 | 7129 (+47.4%) | 341440 | 321275 (-5.9%) |
|CPU: AMD 9654 * 2 | P96 | P1 |
|Memory: 1536GB |------------------------|-------------------------|
|960GB SSD (1GB/s) | base | patched | base | patched |
|-------------------|-------|----------------|--------|----------------|
|mb_optimize_scan=0 | 22341 | 53760 (+140%) | 219707 | 213145 (-2.9%) |
|mb_optimize_scan=1 | 9177 | 12716 (+38.5%) | 215732 | 215262 (+0.2%) |
Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://patch.msgid.link/20250714130327.1830534-6-libaokun1@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
After we optimized the block group lock, we found another lock
contention issue when running will-it-scale/fallocate2 with multiple
processes. The fallocate's block allocation and the truncate's block
release were fighting over the s_md_lock. The problem is, this lock
protects totally different things in those two processes: the list of
freed data blocks (s_freed_data_list) when releasing, and where to start
looking for new blocks (mb_last_group) when allocating.
Now we only need to track s_mb_last_group and no longer need to track
s_mb_last_start, so we don't need the s_md_lock lock to ensure that the
two are consistent. Since s_mb_last_group is merely a hint and doesn't
require strong synchronization, READ_ONCE/WRITE_ONCE is sufficient.
Besides, the s_mb_last_group data type only requires ext4_group_t
(i.e., unsigned int), rendering unsigned long superfluous.
Performance test data follows:
Test: Running will-it-scale/fallocate2 on CPU-bound containers.
Observation: Average fallocate operations per container per second.
|CPU: Kunpeng 920 | P80 | P1 |
|Memory: 512GB |------------------------|-------------------------|
|960GB SSD (0.5GB/s)| base | patched | base | patched |
|-------------------|-------|----------------|--------|----------------|
|mb_optimize_scan=0 | 4821 | 9636 (+99.8%) | 314065 | 337597 (+7.4%) |
|mb_optimize_scan=1 | 4784 | 4834 (+1.04%) | 316344 | 341440 (+7.9%) |
|CPU: AMD 9654 * 2 | P96 | P1 |
|Memory: 1536GB |------------------------|-------------------------|
|960GB SSD (1GB/s) | base | patched | base | patched |
|-------------------|-------|----------------|--------|----------------|
|mb_optimize_scan=0 | 15371 | 22341 (+45.3%) | 205851 | 219707 (+6.7%) |
|mb_optimize_scan=1 | 6101 | 9177 (+50.4%) | 207373 | 215732 (+4.0%) |
Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://patch.msgid.link/20250714130327.1830534-5-libaokun1@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
When ext4 allocates blocks, we used to just go through the block groups
one by one to find a good one. But when there are tons of block groups
(like hundreds of thousands or even millions) and not many have free space
(meaning they're mostly full), it takes a really long time to check them
all, and performance gets bad. So, we added the "mb_optimize_scan" mount
option (which is on by default now). It keeps track of some group lists,
so when we need a free block, we can just grab a likely group from the
right list. This saves time and makes block allocation much faster.
But when multiple processes or containers are doing similar things, like
constantly allocating 8k blocks, they all try to use the same block group
in the same list. Even just two processes doing this can cut the IOPS in
half. For example, one container might do 300,000 IOPS, but if you run two
at the same time, the total is only 150,000.
Since we can already look at block groups in a non-linear way, the first
and last groups in the same list are basically the same for finding a block
right now. Therefore, add an ext4_try_lock_group() helper function to skip
the current group when it is locked by another process, thereby avoiding
contention with other processes. This helps ext4 make better use of having
multiple block groups.
Also, to make sure we don't skip all the groups that have free space
when allocating blocks, we won't try to skip busy groups anymore when
ac_criteria is CR_ANY_FREE.
Performance test data follows:
Test: Running will-it-scale/fallocate2 on CPU-bound containers.
Observation: Average fallocate operations per container per second.
|CPU: Kunpeng 920 | P80 |
|Memory: 512GB |-------------------------|
|960GB SSD (0.5GB/s)| base | patched |
|-------------------|-------|-----------------|
|mb_optimize_scan=0 | 2667 | 4821 (+80.7%) |
|mb_optimize_scan=1 | 2643 | 4784 (+81.0%) |
|CPU: AMD 9654 * 2 | P96 |
|Memory: 1536GB |-------------------------|
|960GB SSD (1GB/s) | base | patched |
|-------------------|-------|-----------------|
|mb_optimize_scan=0 | 3450 | 15371 (+345%) |
|mb_optimize_scan=1 | 3209 | 6101 (+90.0%) |
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://patch.msgid.link/20250714130327.1830534-2-libaokun1@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
There was a lot of common code in the codepaths used to convert an
inline directory and to creaet a new directory. To address this,
rename ext4_init_dot_dotdot() to ext4_init_dirblock() and then move
common code into that function.
This reduces the lines of code count in fs/ext4/inline.c and
fs/ext4/namei.c, as well as reducing the size of their object files.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Link: https://patch.msgid.link/20250712181249.434530-3-tytso@mit.edu
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
After ext4 supports large folios, the semantics of reserving credits in
pages is no longer applicable. In most scenarios, reserving credits in
extents is sufficient. Therefore, introduce ext4_chunk_trans_extent()
to replace ext4_writepage_trans_blocks(). move_extent_per_page() is the
only remaining location where we are still processing extents in pages.
Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20250707140814.542883-10-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
