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7 daysMerge tag 'for-6.19-rc1-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fixes from David Sterba: - fix missing btrfs_path release after printing a relocation error message - fix extent changeset leak on mmap write after failure to reserve metadata - fix fs devices list structure freeing, it could be potentially leaked under some circumstances - tree log fixes: - fix incremental directory logging where inodes for new dentries were incorrectly skipped - don't log conflicting inode if it's a directory moved in the current transaction - regression fixes: - fix incorrect btrfs_path freeing when it's auto-cleaned - revert commit simplifying preallocation of temporary structures in qgroup functions, some cases were not handled properly * tag 'for-6.19-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: fix changeset leak on mmap write after failure to reserve metadata btrfs: fix memory leak of fs_devices in degraded seed device path btrfs: fix a potential path leak in print_data_reloc_error() Revert "btrfs: add ASSERTs on prealloc in qgroup functions" btrfs: do not skip logging new dentries when logging a new name btrfs: don't log conflicting inode if it's a dir moved in the current transaction btrfs: tests: fix double btrfs_path free in remove_extent_ref()
10 daysbtrfs: fix changeset leak on mmap write after failure to reserve metadataFilipe Manana
If the call to btrfs_delalloc_reserve_metadata() fails we jump to the 'out_noreserve' label and there we never free the extent_changeset allocated by the previous call to btrfs_check_data_free_space() (if qgroups are enabled). Fix this by calling extent_changeset_free() under the 'out_noreserve' label. Fixes: 6599716de2d6 ("btrfs: fix -ENOSPC mmap write failure on NOCOW files/extents") Reported-by: syzbot+2f8aa76e6acc9fce6638@syzkaller.appspotmail.com Link: https://lore.kernel.org/linux-btrfs/693a635a.a70a0220.33cd7b.0029.GAE@google.com/ 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>
2025-12-03Merge tag 'for-6.19-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs updates from David Sterba: "Features: - shutdown ioctl support (needs CONFIG_BTRFS_EXPERIMENTAL for now): - set filesystem state as being shut down (also named going down in other filesystems), where all active operations return EIO and this cannot be changed until unmount - pending operations are attempted to be finished but error messages may still show up depending on where exactly the shutdown happened - scrub (and device replace) vs suspend/hibernate: - a running scrub will prevent suspend, which can be annoying as suspend is an immediate request and scrub is not critical - filesystem freezing before suspend was not sufficient as the problem was in process freezing - behaviour change: on suspend scrub and device replace are cancelled, where scrub can record the last state and continue from there; the device replace has to be restarted from the beginning - zone stats exported in sysfs, from the perspective of the filesystem this includes active, reclaimable, relocation etc zones Performance: - improvements when processing space reservation tickets by optimizing locking and shrinking critical sections, cumulative improvements in lockstat numbers show +15% Notable fixes: - use vmalloc fallback when allocating bios as high order allocations can happen with wide checksums (like sha256) - scrub will always track the last position of progress so it's not starting from zero after an error Core: - under experimental config, checksum calculations are offloaded to process context, simplifies locking and allows to remove compression write worker kthread(s): - speed improvement in direct IO throughput with buffered IO fallback is +15% when not offloaded but this is more related to internal crypto subsystem improvements - this will be probably default in the future removing the sysfs tunable - (experimental) block size > page size updates: - support more operations when not using large folios (encoded read/write and send) - raid56 - more preparations for fscrypt support Other: - more conversions to auto-cleaned variables - parameter cleanups and removals - extended warning fixes - improved printing of structured values like keys - lots of other cleanups and refactoring" * tag 'for-6.19-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (147 commits) btrfs: remove unnecessary inode key in btrfs_log_all_parents() btrfs: remove redundant zero/NULL initializations in btrfs_alloc_root() btrfs: remaining BTRFS_PATH_AUTO_FREE conversions btrfs: send: do not allocate memory for xattr data when checking it exists btrfs: send: add unlikely to all unexpected overflow checks btrfs: reduce arguments to btrfs_del_inode_ref_in_log() btrfs: remove root argument from btrfs_del_dir_entries_in_log() btrfs: use test_and_set_bit() in btrfs_delayed_delete_inode_ref() btrfs: don't search back for dir inode item in INO_LOOKUP_USER btrfs: don't rewrite ret from inode_permission btrfs: add orig_logical to btrfs_bio for encryption btrfs: disable verity on encrypted inodes btrfs: disable various operations on encrypted inodes btrfs: remove redundant level reset in btrfs_del_items() btrfs: simplify leaf traversal after path release in btrfs_next_old_leaf() btrfs: optimize balance_level() path reference handling btrfs: factor out root promotion logic into promote_child_to_root() btrfs: raid56: remove the "_step" infix btrfs: raid56: enable bs > ps support btrfs: raid56: prepare finish_parity_scrub() to support bs > ps cases ...
2025-12-01Merge tag 'vfs-6.19-rc1.folio' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull folio updates from Christian Brauner: "Add a new folio_next_pos() helper function that returns the file position of the first byte after the current folio. This is a common operation in filesystems when needing to know the end of the current folio. The helper is lifted from btrfs which already had its own version, and is now used across multiple filesystems and subsystems: - btrfs - buffer - ext4 - f2fs - gfs2 - iomap - netfs - xfs - mm This fixes a long-standing bug in ocfs2 on 32-bit systems with files larger than 2GiB. Presumably this is not a common configuration, but the fix is backported anyway. The other filesystems did not have bugs, they were just mildly inefficient. This also introduce uoff_t as the unsigned version of loff_t. A recent commit inadvertently changed a comparison from being unsigned (on 64-bit systems) to being signed (which it had always been on 32-bit systems), leading to sporadic fstests failures. Generally file sizes are restricted to being a signed integer, but in places where -1 is passed to indicate "up to the end of the file", it is convenient to have an unsigned type to ensure comparisons are always unsigned regardless of architecture" * tag 'vfs-6.19-rc1.folio' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: fs: Add uoff_t mm: Use folio_next_pos() xfs: Use folio_next_pos() netfs: Use folio_next_pos() iomap: Use folio_next_pos() gfs2: Use folio_next_pos() f2fs: Use folio_next_pos() ext4: Use folio_next_pos() buffer: Use folio_next_pos() btrfs: Use folio_next_pos() filemap: Add folio_next_pos()
2025-11-24btrfs: introduce a new shutdown stateQu Wenruo
A new fs state EMERGENCY_SHUTDOWN is introduced, which is btrfs' equivalent of XFS_IOC_GOINGDOWN or EXT4_IOC_SHUTDOWN, after entering emergency shutdown state, all operations will return errors (-EIO), and can not be bring back to normal state until unmouont. The new state will reject the following file operations: - read_iter() - write_iter() - mmap() - open() - remap_file_range() - uring_cmd() - splice_read() This requires a small wrapper to do the extra shutdown check, then call the regular filemap_splice_read() function This should reject most of the file operations on a shutdown btrfs. And for the existing dirty folios, extra shutdown checks are introduced to the following functions: - run_delalloc_nocow() - run_delalloc_compressed() - cow_file_range() So that dirty ranges will still be properly cleaned without being submitted. Finally the shutdown state will also set the fs error, so that no new transaction will be committed, protecting the metadata from any possible further corruption. And when the fs entered shutdown mode for the first time, a critical level kernel message will show up to indicate the incident. That message will be important for end users as rejected delalloc ranges will output error messages, hopefully that shutdown message and the fact that all fs operations are returning error will prevent end users from getting too confused about the delalloc error messages. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Anand Jain <asj@kernel.org> Tested-by: Anand Jain <asj@kernel.org> Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-11-24btrfs: use end_pos variable where needed in btrfs_dirty_folio()Filipe Manana
We have a couple places doing the computation "pos + write_bytes" when we already have it in the local variable "end_pos". Change then to use the variable instead and make source code smaller. Also make the variable const since it's not supposed to change. This also has a very slight reduction in the module size. Before: $ size fs/btrfs/btrfs.ko text data bss dec hex filename 1915990 161647 15592 2093229 1ff0ad fs/btrfs/btrfs.ko After: $ size fs/btrfs/btrfs.ko text data bss dec hex filename 1915974 161647 15592 2093213 1ff09d fs/btrfs/btrfs.ko 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>
2025-10-31btrfs: Use folio_next_pos()Matthew Wilcox (Oracle)
btrfs defined its own variant of folio_next_pos() called folio_end(). This is an ambiguous name as 'end' might be exclusive or inclusive. Switch to the new folio_next_pos(). Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Link: https://patch.msgid.link/20251024170822.1427218-3-willy@infradead.org Acked-by: David Sterba <dsterba@suse.com> Cc: Chris Mason <clm@fb.com> Cc: David Sterba <dsterba@suse.com> Cc: linux-btrfs@vger.kernel.org Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-10-30btrfs: mark dirty extent range for out of bound prealloc extentsaustinchang
In btrfs_fallocate(), when the allocated range overlaps with a prealloc extent and the extent starts after i_size, the range doesn't get marked dirty in file_extent_tree. This results in persisting an incorrect disk_i_size for the inode when not using the no-holes feature. This is reproducible since commit 41a2ee75aab0 ("btrfs: introduce per-inode file extent tree"), then became hidden since commit 3d7db6e8bd22 ("btrfs: don't allocate file extent tree for non regular files") and then visible again after commit 8679d2687c35 ("btrfs: initialize inode::file_extent_tree after i_mode has been set"), which fixes the previous commit. The following reproducer triggers the problem: $ cat test.sh MNT=/mnt/test DEV=/dev/vdb mkdir -p $MNT mkfs.btrfs -f -O ^no-holes $DEV mount $DEV $MNT touch $MNT/file1 fallocate -n -o 1M -l 2M $MNT/file1 umount $MNT mount $DEV $MNT len=$((1 * 1024 * 1024)) fallocate -o 1M -l $len $MNT/file1 du --bytes $MNT/file1 umount $MNT mount $DEV $MNT du --bytes $MNT/file1 umount $MNT Running the reproducer gives the following result: $ ./test.sh (...) 2097152 /mnt/test/file1 1048576 /mnt/test/file1 The difference is exactly 1048576 as we assigned. Fix by adding a call to btrfs_inode_set_file_extent_range() in btrfs_fallocate_update_isize(). Fixes: 41a2ee75aab0 ("btrfs: introduce per-inode file extent tree") Signed-off-by: austinchang <austinchang@synology.com> Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-09-23btrfs: add unlikely annotations to branches leading to transaction abortDavid Sterba
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. Transaction abort is one such error, the btrfs_abort_transaction() inlines code to check the state and print a warning, this ought to be out of the hot path. The most common pattern is when transaction abort is called after checking a return value and the control flow leads to a quick return. In other cases it may not be necessary to add unlikely() e.g. when the function returns anyway or the control flow is not changed noticeably. Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-09-23btrfs: add unlikely annotations to branches leading to EIODavid Sterba
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>
2025-09-23btrfs: fix typos in comments and stringsDavid Sterba
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>
2025-07-28Merge tag 'vfs-6.17-rc1.mmap_prepare' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull mmap_prepare updates from Christian Brauner: "Last cycle we introduce f_op->mmap_prepare() in c84bf6dd2b83 ("mm: introduce new .mmap_prepare() file callback"). This is preferred to the existing f_op->mmap() hook as it does require a VMA to be established yet, thus allowing the mmap logic to invoke this hook far, far earlier, prior to inserting a VMA into the virtual address space, or performing any other heavy handed operations. This allows for much simpler unwinding on error, and for there to be a single attempt at merging a VMA rather than having to possibly reattempt a merge based on potentially altered VMA state. Far more importantly, it prevents inappropriate manipulation of incompletely initialised VMA state, which is something that has been the cause of bugs and complexity in the past. The intent is to gradually deprecate f_op->mmap, and in that vein this series coverts the majority of file systems to using f_op->mmap_prepare. Prerequisite steps are taken - firstly ensuring all checks for mmap capabilities use the file_has_valid_mmap_hooks() helper rather than directly checking for f_op->mmap (which is now not a valid check) and secondly updating daxdev_mapping_supported() to not require a VMA parameter to allow ext4 and xfs to be converted. Commit bb666b7c2707 ("mm: add mmap_prepare() compatibility layer for nested file systems") handles the nasty edge-case of nested file systems like overlayfs, which introduces a compatibility shim to allow f_op->mmap_prepare() to be invoked from an f_op->mmap() callback. This allows for nested filesystems to continue to function correctly with all file systems regardless of which callback is used. Once we finally convert all file systems, this shim can be removed. As a result, ecryptfs, fuse, and overlayfs remain unaltered so they can nest all other file systems. We additionally do not update resctl - as this requires an update to remap_pfn_range() (or an alternative to it) which we defer to a later series, equally we do not update cramfs which needs a mixed mapping insertion with the same issue, nor do we update procfs, hugetlbfs, syfs or kernfs all of which require VMAs for internal state and hooks. We shall return to all of these later" * tag 'vfs-6.17-rc1.mmap_prepare' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: doc: update porting, vfs documentation to describe mmap_prepare() fs: replace mmap hook with .mmap_prepare for simple mappings fs: convert most other generic_file_*mmap() users to .mmap_prepare() fs: convert simple use of generic_file_*_mmap() to .mmap_prepare() mm/filemap: introduce generic_file_*_mmap_prepare() helpers fs/xfs: transition from deprecated .mmap hook to .mmap_prepare fs/ext4: transition from deprecated .mmap hook to .mmap_prepare fs/dax: make it possible to check dev dax support without a VMA fs: consistently use can_mmap_file() helper mm/nommu: use file_has_valid_mmap_hooks() helper mm: rename call_mmap/mmap_prepare to vfs_mmap/mmap_prepare
2025-07-22btrfs: make btrfs_check_nocow_lock() check more than one extentFilipe Manana
Currently btrfs_check_nocow_lock() stops at the first extent it finds and that extent may be smaller than the target range we want to NOCOW into. But we can have multiple consecutive extents which we can NOCOW into, so by stopping at the first one we find we just make the caller do more work by splitting the write into multiple ones, or in the case of mmap writes with large folios we fail with -ENOSPC in case the folio's range is covered by more than one extent (the fallback to NOCOW for mmap writes in case there's no available data space to reserve/allocate was recently added by the patch "btrfs: fix -ENOSPC mmap write failure on NOCOW files/extents"). Improve on this by checking for multiple consecutive extents. Reviewed-by: Boris Burkov <boris@bur.io> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-07-22btrfs: update function comment for btrfs_check_nocow_lock()Filipe Manana
The documentation for the @nowait parameter is missing, so add it. The @nowait parameter was added in commit 80f9d24130e4 ("btrfs: make btrfs_check_nocow_lock nowait compatible"), which forgot to update the function comment. 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>
2025-07-22btrfs: use btrfs_inode local variable at btrfs_page_mkwrite()Filipe Manana
Most of the time we want to use the btrfs_inode, so change the local inode variable to be a btrfs_inode instead of a VFS inode, reducing verbosity by eliminating a lot of BTRFS_I() calls. 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>
2025-07-22btrfs: use variable for io_tree when clearing range in btrfs_page_mkwrite()Filipe Manana
We have the inode's io_tree already stored in a local variable, so use it instead of grabbing it again in the call to btrfs_clear_extent_bit(). 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>
2025-07-22btrfs: fix -ENOSPC mmap write failure on NOCOW files/extentsFilipe Manana
If we attempt a mmap write into a NOCOW file or a prealloc extent when there is no more available data space (or unallocated space to allocate a new data block group) and we can do a NOCOW write (there are no reflinks for the target extent or snapshots), we always fail due to -ENOSPC, unlike for the regular buffered write and direct IO paths where we check that we can do a NOCOW write in case we can't reserve data space. Simple reproducer: $ cat test.sh #!/bin/bash DEV=/dev/sdi MNT=/mnt/sdi umount $DEV &> /dev/null mkfs.btrfs -f -b $((512 * 1024 * 1024)) $DEV mount $DEV $MNT touch $MNT/foobar # Make it a NOCOW file. chattr +C $MNT/foobar # Add initial data to file. xfs_io -c "pwrite -S 0xab 0 1M" $MNT/foobar # Fill all the remaining data space and unallocated space with data. dd if=/dev/zero of=$MNT/filler bs=4K &> /dev/null # Overwrite the file with a mmap write. Should succeed. xfs_io -c "mmap -w 0 1M" \ -c "mwrite -S 0xcd 0 1M" \ -c "munmap" \ $MNT/foobar # Unmount, mount again and verify the new data was persisted. umount $MNT mount $DEV $MNT od -A d -t x1 $MNT/foobar umount $MNT Running this: $ ./test.sh (...) wrote 1048576/1048576 bytes at offset 0 1 MiB, 256 ops; 0.0008 sec (1.188 GiB/sec and 311435.5231 ops/sec) ./test.sh: line 24: 234865 Bus error xfs_io -c "mmap -w 0 1M" -c "mwrite -S 0xcd 0 1M" -c "munmap" $MNT/foobar 0000000 ab ab ab ab ab ab ab ab ab ab ab ab ab ab ab ab * 1048576 Fix this by not failing in case we can't allocate data space and we can NOCOW into the target extent - reserving only metadata space in this case. After this change the test passes: $ ./test.sh (...) wrote 1048576/1048576 bytes at offset 0 1 MiB, 256 ops; 0.0007 sec (1.262 GiB/sec and 330749.3540 ops/sec) 0000000 cd cd cd cd cd cd cd cd cd cd cd cd cd cd cd cd * 1048576 A test case for fstests will be added soon. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-07-21btrfs: use pgoff_t for page index variablesDavid Sterba
Any conversion of offsets in the logical or the physical mapping space of the pages is done by a shift and the target type should be pgoff_t (type of struct page::index). Fix the locations where it's still unsigned long. Signed-off-by: David Sterba <dsterba@suse.com>
2025-07-21btrfs: use folio_next_index() helper in check_range_has_page()Qianfeng Rong
Simplify code pattern of 'folio->index + folio_nr_pages(folio)' by using the existing helper folio_next_index(). Signed-off-by: Qianfeng Rong <rongqianfeng@vivo.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-07-21btrfs: use folio_end() where appropriateDavid Sterba
Simplify folio_pos() + folio_size() and use the new helper. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-07-21btrfs: use on-stack variable for block reserve in btrfs_replace_file_extents()David Sterba
We can avoid potential memory allocation failure in btrfs_replace_file_extents() as the block reserve lifetime is limited to the scope of the function. This requires +48 bytes on stack. Signed-off-by: David Sterba <dsterba@suse.com>
2025-06-19fs: replace mmap hook with .mmap_prepare for simple mappingsLorenzo Stoakes
Since commit c84bf6dd2b83 ("mm: introduce new .mmap_prepare() file callback"), the f_op->mmap() hook has been deprecated in favour of f_op->mmap_prepare(). This callback is invoked in the mmap() logic far earlier, so error handling can be performed more safely without complicated and bug-prone state unwinding required should an error arise. This hook also avoids passing a pointer to a not-yet-correctly-established VMA avoiding any issues with referencing this data structure. It rather provides a pointer to the new struct vm_area_desc descriptor type which contains all required state and allows easy setting of required parameters without any consideration needing to be paid to locking or reference counts. Note that nested filesystems like overlayfs are compatible with an .mmap_prepare() callback since commit bb666b7c2707 ("mm: add mmap_prepare() compatibility layer for nested file systems"). In this patch we apply this change to file systems with relatively simple mmap() hook logic - exfat, ceph, f2fs, bcachefs, zonefs, btrfs, ocfs2, orangefs, nilfs2, romfs, ramfs and aio. Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Link: https://lore.kernel.org/f528ac4f35b9378931bd800920fee53fc0c5c74d.1750099179.git.lorenzo.stoakes@oracle.com Acked-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-05-15btrfs: use a single variable to track return value at btrfs_page_mkwrite()Filipe Manana
We have two variables to track return values, ret and ret2, with types vm_fault_t (an unsigned int type) and int, which makes it a bit confusing and harder to keep track. So use a single variable, of type int, and under the 'out' label return vmf_error(ret) in case ret contains an error, otherwise return VM_FAULT_NOPAGE. This is equivalent to what we had before and it's simpler. 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>
2025-05-15btrfs: don't return VM_FAULT_SIGBUS on failure to set delalloc for mmap writeFilipe Manana
If the call to btrfs_set_extent_delalloc() fails we are always returning VM_FAULT_SIGBUS, which is odd since the error means "bad access" and the most likely cause for btrfs_set_extent_delalloc() is -ENOMEM, which should be translated to VM_FAULT_OOM. Instead of returning VM_FAULT_SIGBUS return vmf_error(ret2), which gives us a more appropriate return value, and we use that everywhere else too. 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>
2025-05-15btrfs: simplify early error checking in btrfs_page_mkwrite()Filipe Manana
We have this entangled error checks early at btrfs_page_mkwrite(): 1) Try to reserve delalloc space by calling btrfs_delalloc_reserve_space() and storing the return value in the ret2 variable; 2) If the reservation succeed, call file_update_time() and store the return value in ret2 and also set the local variable 'reserved' to true (1); 3) Then do an error check on ret2 to see if any of the previous calls failed and if so, jump either to the 'out' label or to the 'out_noreserve' label, depending on whether 'reserved' is true or not. This is unnecessarily complex. Instead change this to a simpler and more straightforward approach: 1) Call btrfs_delalloc_reserve_space(), if that returns an error jump to the 'out_noreserve' label; 2) The call file_update_time() and if that returns an error jump to the 'out' label. Like this there's less nested if statements, no need to use a local variable to track if space was reserved and if statements are used only to check errors. Also move the call to extent_changeset_free() out of the 'out_noreserve' label and under the 'out' label since the changeset is allocated only if the call to reserve delalloc space succeeded. 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>
2025-05-15btrfs: pass true to btrfs_delalloc_release_space() at btrfs_page_mkwrite()Filipe Manana
In the last call to btrfs_delalloc_release_space() where the value of the variable 'ret' is never zero, we pass the expression 'ret != 0' as the value for the argument 'qgroup_free', which always evaluates to true. Make this less confusing and more clear by explicitly passing true instead. 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>
2025-05-15btrfs: fix wrong start offset for delalloc space release during mmap writeFilipe Manana
If we're doing a mmap write against a folio that has i_size somewhere in the middle and we have multiple sectors in the folio, we may have to release excess space previously reserved, for the range going from the rounded up (to sector size) i_size to the folio's end offset. We are calculating the right amount to release and passing it to btrfs_delalloc_release_space(), but we are passing the wrong start offset of that range - we're passing the folio's start offset instead of the end offset, plus 1, of the range for which we keep the reservation. This may result in releasing more space then we should and eventually trigger an underflow of the data space_info's bytes_may_use counter. So fix this by passing the start offset as 'end + 1' instead of 'page_start' to btrfs_delalloc_release_space(). Fixes: d0b7da88f640 ("Btrfs: btrfs_page_mkwrite: Reserve space in sectorsized units") 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>
2025-05-15btrfs: simplify error return logic when getting folio at prepare_one_folio()Filipe Manana
There's no need to have special logic to return -EAGAIN in case the call to __filemap_get_folio() fails, because when FGP_NOWAIT is passed to __filemap_get_folio() it returns ERR_PTR(-EAGAIN) if it needs to do something that would imply blocking. The reason we have this logic is from the days before we migrated to the folio interface, when we called pagecache_get_page() which would return NULL instead of an error pointer. So remove this special casing and always return the error that the call to __filemap_get_folio() returned. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> 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>
2025-05-15btrfs: handle unaligned EOF truncation correctly for subpage casesQu Wenruo
[BUG] The following fsx sequence will fail on btrfs with 64K page size and 4K fs block size: #fsx -d -e 1 -N 4 $mnt/junk -S 36386 READ BAD DATA: offset = 0xe9ba, size = 0x6dd5, fname = /mnt/btrfs/junk OFFSET GOOD BAD RANGE 0xe9ba 0x0000 0x03ac 0x0 operation# (mod 256) for the bad data may be 3 ... LOG DUMP (4 total operations): 1( 1 mod 256): WRITE 0x6c62 thru 0x1147d (0xa81c bytes) HOLE ***WWWW 2( 2 mod 256): TRUNCATE DOWN from 0x1147e to 0x5448 ******WWWW 3( 3 mod 256): ZERO 0x1c7aa thru 0x28fe2 (0xc839 bytes) 4( 4 mod 256): MAPREAD 0xe9ba thru 0x1578e (0x6dd5 bytes) ***RRRR*** [CAUSE] Only 2 operations are really involved in this case: 3 pollute_eof 0x5448 thru 0xffff (0xabb8 bytes) 3 zero from 0x1c7aa to 0x28fe3, (0xc839 bytes) 4 mapread 0xe9ba thru 0x1578e (0x6dd5 bytes) At operation 3, fsx pollutes beyond EOF, that is done by mmap() and write into that mmap() range beyond EOF. Such write will fill the range beyond EOF, but it will never reach disk as ranges beyond EOF will not be marked dirty nor uptodate. Then we zero_range for [0x1c7aa, 0x28fe3], and since the range is beyond our isize (which was 0x5448), we should zero out any range beyond EOF (0x5448). During btrfs_zero_range(), we call btrfs_truncate_block() to dirty the unaligned head block. But that function only really zeroes out the block at [0x5000, 0x5fff], it doesn't bother any range other that that block, since those ranges will not be marked dirty nor written back. So the range [0x6000, 0xffff] is still polluted, and later mapread() will return the poisoned value. [FIX] Enhance btrfs_truncate_block() by: - Pass a @start/@end pair to indicate the full truncation range This is to handle the following truncation case: Page size is 64K, fs block size is 4K, truncate range is [6K, 60K] 0 32K 64K | |///////////////////////////////////| | 6K 60K The range is not aligned for its head block, so we need to call btrfs_truncate_block() with @from = 6K, @front = 0, @len = 0. But with that information we only know to zero the range [6K, 8K), if we zero out the range [6K, 64K), the last block will also be zeroed, causing data loss. So here we need the full range we're truncating, so that we can avoid over-truncation. - Rename @from to @offset As now the parameter is only utilized to locate a block, it's not really carrying the old @from meaning well. - Remove @front parameter With the full truncate range passed in, we can determine if the @offset is at the head or tail block. - Skip truncation if @offset is not in the head nor tail blocks The call site in hole punch unconditionally call btrfs_truncate_block() without even checking the range is aligned or not. If the @offset is neither in the head nor in tail block, it means we can safely ignore it. - Skip truncate if the range inside the target block is already aligned - Make btrfs_truncate_block() zero all blocks beyond EOF Since we have the original range, we know exactly if we're doing truncation beyond EOF (the @end will be (u64)-1). If we're doing truncation beyond EOF, then enlarge the truncation range to the folio end, to address the possibly polluted ranges. Otherwise still keep the zero range inside the block, as we can have large data folios soon, always truncating every blocks inside the same folio can be costly for large folios. Reviewed-by: Boris Burkov <boris@bur.io> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-05-15btrfs: trivial conversion to return bool instead of intDavid Sterba
Old code has a lot of int for bool return values, bool is recommended and done in new code. Convert the trivial cases that do simple 0/false and 1/true. Functions comment are updated if needed. Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-05-15btrfs: rename iov_iter iterator parameter in btrfs_buffered_write()David Sterba
Using 'i' for a parameter is confusing and conforming to current preferences, so rename it to 'iter'. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-05-15btrfs: rename functions to allocate and free extent mapsFilipe Manana
These functions are exported and don't have a 'btrfs_' prefix in their names, which goes against coding style conventions. Rename them to have such prefix, making it clear they are from btrfs and avoiding potential collisions in the future with functions defined elsewhere outside btrfs. Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-05-15btrfs: rename extent map functions to get block start, end and check if in treeFilipe Manana
These functions are exported and don't have a 'btrfs_' prefix in their names, which goes against coding style conventions. Rename them to have such prefix, making it clear they are from btrfs and avoiding potential collisions in the future with functions defined elsewhere outside btrfs. Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-05-15btrfs: rename free_extent_state() to include a btrfs prefixFilipe Manana
This is an exported function so it should have a 'btrfs_' prefix by convention, to make it clear it's btrfs specific and to avoid collisions with functions from elsewhere in the kernel. Rename the function to add 'btrfs_' prefix to it. 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>
2025-05-15btrfs: rename the functions to count, test and get bit ranges in io treesFilipe Manana
These functions are exported so they should have a 'btrfs_' prefix by convention, to make it clear they are btrfs specific and to avoid collisions with functions from elsewhere in the kernel. So add a 'btrfs_' prefix to their names to make it clear they are from btrfs. 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>
2025-05-15btrfs: rename the functions to clear bits for an extent rangeFilipe Manana
These functions are exported so they should have a 'btrfs_' prefix by convention, to make it clear they are btrfs specific and to avoid collisions with functions from elsewhere in the kernel. One of them has a double underscore prefix which is also discouraged. So remove double underscore prefix where applicable and add a 'btrfs_' prefix to their name to make it clear they are from btrfs. 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>
2025-05-15btrfs: add btrfs prefix to main lock, try lock and unlock extent functionsFilipe Manana
These functions are exported so they should have a 'btrfs_' prefix by convention, to make it clear they are btrfs specific and to avoid collisions with functions from elsewhere in the kernel. So add a prefix to their name. 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>
2025-05-15btrfs: prepare prepare_one_folio() for large data foliosQu Wenruo
The only blockage is the ASSERT() rejecting large folios, just remove it. Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-05-15btrfs: prepare btrfs_page_mkwrite() for large data foliosQu Wenruo
The function btrfs_page_mkwrite() has an explicit ASSERT() checking the folio order. To make it support large data folios, we need to: - Remove the ASSERT(folio_order(folio) == 0) - Use folio_contains() to check if the folio covers the last page Otherwise the code is already supporting large folios well. Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-05-15btrfs: do more trivial BTRFS_PATH_AUTO_FREE conversionsDavid Sterba
The most trivial pattern for the auto freeing when the variable is declared with the macro and the final btrfs_free_path() is removed. There are almost none goto -> return conversions and there's no other function cleanup. Reviewed-by: Daniel Vacek <neelx@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-05-15btrfs: prepare btrfs_punch_hole_lock_range() for large data foliosQu Wenruo
The function btrfs_punch_hole_lock_range() needs to make sure there is no other folio in the range, thus it goes with filemap_range_has_page(), which works pretty fine. But if we have large folios, under the following case filemap_range_has_page() will always return true, forcing btrfs_punch_hole_lock_range() to do a very time consuming busy loop: start end | | |//|//|//|//| | | | | | | | |//|//| \ / \ / Folio A Folio B In the above case, folio A and B contain our start/end indexes, and there are no other folios in the range. Thus we do not need to retry inside btrfs_punch_hole_lock_range(). To prepare for large data folios, introduce a helper, check_range_has_page(), which will: - Shrink the search range towards page boundaries If the rounded down end (exclusive, otherwise it can underflow when @end is inside the folio at file offset 0) is no larger than the rounded up start, it means the range contains no other pages other than the ones covering @start and @end. Can return false directly in that case. - Grab all the folios inside the range - Skip any large folios that cover the start and end indexes - If any other folios are found return true - Otherwise return false This new helper is going to handle both large folios and regular ones. Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-05-15btrfs: prepare btrfs_buffered_write() for large data foliosQu Wenruo
This involves the following modifications: - Set the order flags for __filemap_get_folio() inside prepare_one_folio() This will allow __filemap_get_folio() to create a large folio if the address space supports it. - Limit the initial @write_bytes inside copy_one_range() If the largest folio boundary splits the initial write range, there is no way we can write beyond the largest folio boundary. This is done by a simple helper calc_write_bytes(). - Release exceeding reserved space if the folio is smaller than expected Which is doing the same handling when short copy happens. All the preparations should not change the behavior when the largest folio order is 0. Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-05-15btrfs: refactor how we handle reserved space inside copy_one_range()Qu Wenruo
There are several things not ideal in copy_one_range(): - Unnecessary temporary variables * block_offset * reserve_bytes * dirty_blocks * num_blocks * release_bytes These are utilized to handle short-copy cases. - Inconsistent handling of btrfs_delalloc_release_extents() There is a hidden behavior that, after reserving metadata for X bytes of data write, we have to call btrfs_delalloc_release_extents() with X once and only once. Calling btrfs_delalloc_release_extents(X - 4K) and btrfs_delalloc_release_extents(4K) will cause outstanding extents accounting to go wrong. This is because the outstanding extents mechanism is not designed to handle shrinking of reserved space. Improve above situations by: - Use a single @reserved_start and @reserved_len pair Now we reserve space for the initial range, and if a short copy happened and we need to shrink the reserved space, we can easily calculate the new length, and update @reserved_len. - Introduce helpers to shrink reserved data and metadata space This is done by two new helpers, shrink_reserved_space() and btrfs_delalloc_shrink_extents(). The later will do a better calculation if we need to modify the outstanding extents, and the first one will be utilized inside copy_one_range(). - Manually unlock, release reserved space and return if no byte is copied Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-05-15btrfs: factor out the main loop of btrfs_buffered_write() into a helperQu Wenruo
Inside the main loop of btrfs_buffered_write() we are doing a lot of heavy lifting inside a while() loop. This makes it pretty hard to read, factor out the content into a helper, copy_one_range() to do the work. This has no functional change, but with some minor variable renames, e.g. rename all "sector" into "block". Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Filipe Manana <fdmanana@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>
2025-05-15btrfs: factor out space reservation code from btrfs_buffered_write()Qu Wenruo
Inside the main loop of btrfs_buffered_write(), we have a complex data and metadata space reservation code, which tries to reserve space for a COW write, if failed then fallback to check if we can do a NOCOW write. Factor out that part of code into a dedicated helper, reserve_space(), to make the main loop a little easier to read. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Filipe Manana <fdmanana@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>
2025-05-15btrfs: cleanup the reserved space inside loop of btrfs_buffered_write()Qu Wenruo
Inside the main loop of btrfs_buffered_write(), if something wrong happened, there is a out-of-loop cleanup path to release the reserved space. This behavior saves some code lines, but makes it much harder to read, as we need to check release_bytes to make sure when we need to do the cleanup. Factor out the cleanup part into a helper, release_reserved_space(), to do the cleanup inside the main loop, so that we can move @release_bytes inside the loop. This will make later refactoring of the main loop much easier. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-05-15btrfs: remove force_page_uptodate variable from btrfs_buffered_write()Qu Wenruo
Commit c87c299776e4 ("btrfs: make buffered write to copy one page a time") changed how the variable @force_page_uptodate was updated. Before that commit the variable was only initialized to false at the beginning of the function, and after hitting a short copy, the next retry on the same folio would force the folio to be read from the disk. But after the commit, the variable is always initialized to false at the beginning of the loop's scope, causing prepare_one_folio() never to get a true value passed in. The change in behavior is not a huge deal, it only makes a difference on how we handle short copies: Old: Allow the buffer to be split The first short copy will be rejected, that's the same for both cases. But for the next retry, we require the folio to be read from disk. Then even if we hit a short copy again, since the folio is already uptodate, we do not need to handle partial uptodate range, and can continue, marking the short copied range as dirty and continue. This will split the buffer write into the folio as two buffered writes. New: Do not allow the buffer to be split The first short copy will be rejected, that's the same for both cases. For the next retry, we do nothing special, thus if the short copy happened again, we reject it again, until either the short copy is gone, or we failed to fault in the buffer. This will mean the buffer write into the folio will either fail or succeed, no splitting will happen. To me, either solution is fine, but the new one makes it simpler and requires no special handling, so I prefer that solution. And since @force_page_uptodate is always false when passed into prepare_one_folio(), we can just remove the variable. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-04-17btrfs: avoid page_lockend underflow in btrfs_punch_hole_lock_range()Qu Wenruo
[BUG] When running btrfs/004 with 4K fs block size and 64K page size, sometimes fsstress workload can take 100% CPU for a while, but not long enough to trigger a 120s hang warning. [CAUSE] When such 100% CPU usage happens, btrfs_punch_hole_lock_range() is always in the call trace. One example when this problem happens, the function btrfs_punch_hole_lock_range() got the following parameters: lock_start = 4096, lockend = 20469 Then we calculate @page_lockstart by rounding up lock_start to page boundary, which is 64K (page size is 64K). For @page_lockend, we round down the value towards page boundary, which result 0. Then since we need to pass an inclusive end to filemap_range_has_page(), we subtract 1 from the rounded down value, resulting in (u64)-1. In the above case, the range is inside the same page, and we do not even need to call filemap_range_has_page(), not to mention to call it with (u64)-1 at the end. This behavior will cause btrfs_punch_hole_lock_range() to busy loop waiting for irrelevant range to have its pages dropped. [FIX] Calculate @page_lockend by just rounding down @lockend, without decreasing the value by one. So @page_lockend will no longer overflow. Then exit early if @page_lockend is no larger than @page_lockstart. As it means either the range is inside the same page, or the two pages are adjacent already. Finally only decrease @page_lockend when calling filemap_range_has_page(). Fixes: 0528476b6ac7 ("btrfs: fix the filemap_range_has_page() call in btrfs_punch_hole_lock_range()") Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-03-18btrfs: prepare btrfs_page_mkwrite() for large foliosQu Wenruo
This changes the assumption that the folio is always page sized. (Although the ASSERT() for folio order is still kept as-is). Just replace the PAGE_SIZE with folio_size(). Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2025-03-18btrfs: allow buffered write to avoid full page read if it's block alignedQu Wenruo
[BUG] Since the support of block size (sector size) < page size for btrfs, test case generic/563 fails with 4K block size and 64K page size: --- tests/generic/563.out 2024-04-25 18:13:45.178550333 +0930 +++ /home/adam/xfstests-dev/results//generic/563.out.bad 2024-09-30 09:09:16.155312379 +0930 @@ -3,7 +3,8 @@ read is in range write is in range write -> read/write -read is in range +read has value of 8388608 +read is NOT in range -33792 .. 33792 write is in range ... [CAUSE] The test case creates a 8MiB file, then does buffered write into the 8MiB using 4K block size, to overwrite the whole file. On 4K page sized systems, since the write range covers the full block and page, btrfs will not bother reading the page, just like what XFS and EXT4 do. But on 64K page sized systems, although the 4K sized write is still block aligned, it's not page aligned anymore, thus btrfs will read the full page, which will be accounted by cgroup and fail the test. As the test case itself expects such 4K block aligned write should not trigger any read. Such expected behavior is an optimization to reduce folio reads when possible, and unfortunately btrfs does not implement such optimization. [FIX] To skip the full page read, we need to do the following modification: - Do not trigger full page read as long as the buffered write is block aligned This is pretty simple by modifying the check inside prepare_uptodate_page(). - Skip already uptodate blocks during full page read Or we can lead to the following data corruption: 0 32K 64K |///////| | Where the file range [0, 32K) is dirtied by buffered write, the remaining range [32K, 64K) is not. When reading the full page, since [0,32K) is only dirtied but not written back, there is no data extent map for it, but a hole covering [0, 64k). If we continue reading the full page range [0, 64K), the dirtied range will be filled with 0 (since there is only a hole covering the whole range). This causes the dirtied range to get lost. With this optimization, btrfs can pass generic/563 even if the page size is larger than fs block size. Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>