- Avoid 'constexpr', which is a keyword in C23
- Allow 'dtbs_check' and 'dt_compatible_check' run independently of
'dt_binding_check'
- Fix weak references to avoid GOT entries in position-independent
code generation
- Convert the last use of 'optional' property in arch/sh/Kconfig
- Remove support for the 'optional' property in Kconfig
- Remove support for Clang's ThinLTO caching, which does not work with
the .incbin directive
- Change the semantics of $(src) so it always points to the source
directory, which fixes Makefile inconsistencies between upstream and
downstream
- Fix 'make tar-pkg' for RISC-V to produce a consistent package
- Provide reasonable default coverage for objtool, sanitizers, and
profilers
- Remove redundant OBJECT_FILES_NON_STANDARD, KASAN_SANITIZE, etc.
- Remove the last use of tristate choice in drivers/rapidio/Kconfig
- Various cleanups and fixes in Kconfig
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Merge tag 'kbuild-v6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:
- Avoid 'constexpr', which is a keyword in C23
- Allow 'dtbs_check' and 'dt_compatible_check' run independently of
'dt_binding_check'
- Fix weak references to avoid GOT entries in position-independent code
generation
- Convert the last use of 'optional' property in arch/sh/Kconfig
- Remove support for the 'optional' property in Kconfig
- Remove support for Clang's ThinLTO caching, which does not work with
the .incbin directive
- Change the semantics of $(src) so it always points to the source
directory, which fixes Makefile inconsistencies between upstream and
downstream
- Fix 'make tar-pkg' for RISC-V to produce a consistent package
- Provide reasonable default coverage for objtool, sanitizers, and
profilers
- Remove redundant OBJECT_FILES_NON_STANDARD, KASAN_SANITIZE, etc.
- Remove the last use of tristate choice in drivers/rapidio/Kconfig
- Various cleanups and fixes in Kconfig
* tag 'kbuild-v6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (46 commits)
kconfig: use sym_get_choice_menu() in sym_check_prop()
rapidio: remove choice for enumeration
kconfig: lxdialog: remove initialization with A_NORMAL
kconfig: m/nconf: merge two item_add_str() calls
kconfig: m/nconf: remove dead code to display value of bool choice
kconfig: m/nconf: remove dead code to display children of choice members
kconfig: gconf: show checkbox for choice correctly
kbuild: use GCOV_PROFILE and KCSAN_SANITIZE in scripts/Makefile.modfinal
Makefile: remove redundant tool coverage variables
kbuild: provide reasonable defaults for tool coverage
modules: Drop the .export_symbol section from the final modules
kconfig: use menu_list_for_each_sym() in sym_check_choice_deps()
kconfig: use sym_get_choice_menu() in conf_write_defconfig()
kconfig: add sym_get_choice_menu() helper
kconfig: turn defaults and additional prompt for choice members into error
kconfig: turn missing prompt for choice members into error
kconfig: turn conf_choice() into void function
kconfig: use linked list in sym_set_changed()
kconfig: gconf: use MENU_CHANGED instead of SYMBOL_CHANGED
kconfig: gconf: remove debug code
...
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Merge tag 'vfs-6.10.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull misc vfs updates from Christian Brauner:
"This contains the usual miscellaneous features, cleanups, and fixes
for vfs and individual fses.
Features:
- Free up FMODE_* bits. I've freed up bits 6, 7, 8, and 24. That
means we now have six free FMODE_* bits in total (but bit #6
already got used for FMODE_WRITE_RESTRICTED)
- Add FOP_HUGE_PAGES flag (follow-up to FMODE_* cleanup)
- Add fd_raw cleanup class so we can make use of automatic cleanup
provided by CLASS(fd_raw, f)(fd) for O_PATH fds as well
- Optimize seq_puts()
- Simplify __seq_puts()
- Add new anon_inode_getfile_fmode() api to allow specifying f_mode
instead of open-coding it in multiple places
- Annotate struct file_handle with __counted_by() and use
struct_size()
- Warn in get_file() whether f_count resurrection from zero is
attempted (epoll/drm discussion)
- Folio-sophize aio
- Export the subvolume id in statx() for both btrfs and bcachefs
- Relax linkat(AT_EMPTY_PATH) requirements
- Add F_DUPFD_QUERY fcntl() allowing to compare two file descriptors
for dup*() equality replacing kcmp()
Cleanups:
- Compile out swapfile inode checks when swap isn't enabled
- Use (1 << n) notation for FMODE_* bitshifts for clarity
- Remove redundant variable assignment in fs/direct-io
- Cleanup uses of strncpy in orangefs
- Speed up and cleanup writeback
- Move fsparam_string_empty() helper into header since it's currently
open-coded in multiple places
- Add kernel-doc comments to proc_create_net_data_write()
- Don't needlessly read dentry->d_flags twice
Fixes:
- Fix out-of-range warning in nilfs2
- Fix ecryptfs overflow due to wrong encryption packet size
calculation
- Fix overly long line in xfs file_operations (follow-up to FMODE_*
cleanup)
- Don't raise FOP_BUFFER_{R,W}ASYNC for directories in xfs (follow-up
to FMODE_* cleanup)
- Don't call xfs_file_open from xfs_dir_open (follow-up to FMODE_*
cleanup)
- Fix stable offset api to prevent endless loops
- Fix afs file server rotations
- Prevent xattr node from overflowing the eraseblock in jffs2
- Move fdinfo PTRACE_MODE_READ procfs check into the .permission()
operation instead of .open() operation since this caused userspace
regressions"
* tag 'vfs-6.10.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (39 commits)
afs: Fix fileserver rotation getting stuck
selftests: add F_DUPDFD_QUERY selftests
fcntl: add F_DUPFD_QUERY fcntl()
file: add fd_raw cleanup class
fs: WARN when f_count resurrection is attempted
seq_file: Simplify __seq_puts()
seq_file: Optimize seq_puts()
proc: Move fdinfo PTRACE_MODE_READ check into the inode .permission operation
fs: Create anon_inode_getfile_fmode()
xfs: don't call xfs_file_open from xfs_dir_open
xfs: drop fop_flags for directories
xfs: fix overly long line in the file_operations
shmem: Fix shmem_rename2()
libfs: Add simple_offset_rename() API
libfs: Fix simple_offset_rename_exchange()
jffs2: prevent xattr node from overflowing the eraseblock
vfs, swap: compile out IS_SWAPFILE() on swapless configs
vfs: relax linkat() AT_EMPTY_PATH - aka flink() - requirements
fs/direct-io: remove redundant assignment to variable retval
fs/dcache: Re-use value stored to dentry->d_flags instead of re-reading
...
Kbuild conventionally uses $(obj)/ for generated files, and $(src)/ for
checked-in source files. It is merely a convention without any functional
difference. In fact, $(obj) and $(src) are exactly the same, as defined
in scripts/Makefile.build:
src := $(obj)
When the kernel is built in a separate output directory, $(src) does
not accurately reflect the source directory location. While Kbuild
resolves this discrepancy by specifying VPATH=$(srctree) to search for
source files, it does not cover all cases. For example, when adding a
header search path for local headers, -I$(srctree)/$(src) is typically
passed to the compiler.
This introduces inconsistency between upstream and downstream Makefiles
because $(src) is used instead of $(srctree)/$(src) for the latter.
To address this inconsistency, this commit changes the semantics of
$(src) so that it always points to the directory in the source tree.
Going forward, the variables used in Makefiles will have the following
meanings:
$(obj) - directory in the object tree
$(src) - directory in the source tree (changed by this commit)
$(objtree) - the top of the kernel object tree
$(srctree) - the top of the kernel source tree
Consequently, $(srctree)/$(src) in upstream Makefiles need to be replaced
with $(src).
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Directories do not support direct I/O and thus no non-blocking direct
I/O either. Open code the shutdown check and call to generic_file_open
instead.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240423124608.537794-4-hch@lst.de
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Directories have non of the capabilities, so drop the flags. Note that
the current state is harmless as no one actually checks for the flags
either.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240423124608.537794-3-hch@lst.de
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Re-wrap the newly added fop_flags fields to not go over 80 characters.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240423124608.537794-2-hch@lst.de
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
There's a bunch of flags that are purely based on what the file
operations support while also never being conditionally set or unset.
IOW, they're not subject to change for individual files. Imho, such
flags don't need to live in f_mode they might as well live in the fops
structs itself. And the fops struct already has that lonely
mmap_supported_flags member. We might as well turn that into a generic
fop_flags member and move a few flags from FMODE_* space into FOP_*
space. That gets us four FMODE_* bits back and the ability for new
static flags that are about file ops to not have to live in FMODE_*
space but in their own FOP_* space. It's not the most beautiful thing
ever but it gets the job done. Yes, there'll be an additional pointer
chase but hopefully that won't matter for these flags.
I suspect there's a few more we can move into there and that we can also
redirect a bunch of new flag suggestions that follow this pattern into
the fop_flags field instead of f_mode.
Link: https://lore.kernel.org/r/20240328-gewendet-spargel-aa60a030ef74@brauner
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Christian Brauner <brauner@kernel.org>
* Allow creating new links to special files which were not associated with a
project quota.
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
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Merge tag 'xfs-6.9-fixes-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull xfs fix from Chandan Babu:
- Allow creating new links to special files which were not associated
with a project quota
* tag 'xfs-6.9-fixes-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: allow cross-linking special files without project quota
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Merge tag 'vfs-6.9-rc3.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull vfs fixes from Christian Brauner:
"This contains a few small fixes. This comes with some delay because I
wanted to wait on people running their reproducers and the Easter
Holidays meant that those replies came in a little later than usual:
- Fix handling of preventing writes to mounted block devices.
Since last kernel we allow to prevent writing to mounted block
devices provided CONFIG_BLK_DEV_WRITE_MOUNTED isn't set and the
block device is opened with restricted writes. When we switched to
opening block devices as files we altered the mechanism by which we
recognize when a block device has been opened with write
restrictions.
The detection logic assumed that only read-write mounted
filesystems would apply write restrictions to their block devices
from other openers. That of course is not true since it also makes
sense to apply write restrictions for filesystems that are
read-only.
Fix the detection logic using an FMODE_* bit. We still have a few
left since we freed up a couple a while ago. I also picked up a
patch to free up four additional FMODE_* bits scheduled for the
next merge window.
- Fix counting the number of writers to a block device. This just
changes the logic to be consistent.
- Fix a bug in aio causing a NULL pointer derefernce after we
implemented batched processing in aio.
- Finally, add the changes we discussed that allows to yield block
devices early even though file closing itself is deferred.
This also allows us to remove two holder operations to get and
release the holder to align lifetime of file and holder of the
block device"
* tag 'vfs-6.9-rc3.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
aio: Fix null ptr deref in aio_complete() wakeup
fs,block: yield devices early
block: count BLK_OPEN_RESTRICT_WRITES openers
block: handle BLK_OPEN_RESTRICT_WRITES correctly
There's an issue that if special files is created before quota
project is enabled, then it's not possible to link this file. This
works fine for normal files. This happens because xfs_quota skips
special files (no ioctls to set necessary flags). The check for
having the same project ID for source and destination then fails as
source file doesn't have any ID.
mkfs.xfs -f /dev/sda
mount -o prjquota /dev/sda /mnt/test
mkdir /mnt/test/foo
mkfifo /mnt/test/foo/fifo1
xfs_quota -xc "project -sp /mnt/test/foo 9" /mnt/test
> Setting up project 9 (path /mnt/test/foo)...
> xfs_quota: skipping special file /mnt/test/foo/fifo1
> Processed 1 (/etc/projects and cmdline) paths for project 9 with recursion depth infinite (-1).
ln /mnt/test/foo/fifo1 /mnt/test/foo/fifo1_link
> ln: failed to create hard link '/mnt/test/testdir/fifo1_link' => '/mnt/test/testdir/fifo1': Invalid cross-device link
mkfifo /mnt/test/foo/fifo2
ln /mnt/test/foo/fifo2 /mnt/test/foo/fifo2_link
Fix this by allowing linking of special files to the project quota
if special files doesn't have any ID set (ID = 0).
Signed-off-by: Andrey Albershteyn <aalbersh@redhat.com>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
Currently a device is only really released once the umount returns to
userspace due to how file closing works. That ultimately could cause
an old umount assumption to be violated that concurrent umount and mount
don't fail. So an exclusively held device with a temporary holder should
be yielded before the filesystem is gone. Add a helper that allows
callers to do that. This also allows us to remove the two holder ops
that Linus wasn't excited about.
Link: https://lore.kernel.org/r/20240326-vfs-bdev-end_holder-v1-1-20af85202918@kernel.org
Fixes: f3a608827d ("bdev: open block device as files") # mainline only
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
syzbot reported an ext4 panic during a page fault where found a
journal handle when it didn't expect to find one. The structure
it tripped over had a value of 'TRAN' in the first entry in the
structure, and that indicates it tripped over a struct xfs_trans
instead of a jbd2 handle.
The reason for this is that the page fault was taken during a
copy-out to a user buffer from an xfs bulkstat operation. XFS uses
an "empty" transaction context for bulkstat to do automated metadata
buffer cleanup, and so the transaction context is valid across the
copyout of the bulkstat info into the user buffer.
We are using empty transaction contexts like this in XFS to reduce
the risk of failing to release objects we reference during the
operation, especially during error handling. Hence we really need to
ensure that we can take page faults from these contexts without
leaving landmines for the code processing the page fault to trip
over.
However, this same behaviour could happen from any other filesystem
that triggers a page fault or any other exception that is handled
on-stack from within a task context that has current->journal_info
set. Having a page fault from some other filesystem bounce into XFS
where we have to run a transaction isn't a bug at all, but the usage
of current->journal_info means that this could result corruption of
the outer task's journal_info structure.
The problem is purely that we now have two different contexts that
now think they own current->journal_info. IOWs, no filesystem can
allow page faults or on-stack exceptions while current->journal_info
is set by the filesystem because the exception processing might use
current->journal_info itself.
If we end up with nested XFS transactions whilst holding an empty
transaction, then it isn't an issue as the outer transaction does
not hold a log reservation. If we ignore the current->journal_info
usage, then the only problem that might occur is a deadlock if the
exception tries to take the same locks the upper context holds.
That, however, is not a problem that setting current->journal_info
would solve, so it's largely an irrelevant concern here.
IOWs, we really only use current->journal_info for a warning check
in xfs_vm_writepages() to ensure we aren't doing writeback from a
transaction context. Writeback might need to do allocation, so it
can need to run transactions itself. Hence it's a debug check to
warn us that we've done something silly, and largely it is not all
that useful.
So let's just remove all the use of current->journal_info in XFS and
get rid of all the potential issues from nested contexts where
current->journal_info might get misused by another filesystem
context.
Reported-by: syzbot+cdee56dbcdf0096ef605@syzkaller.appspotmail.com
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Mark Tinguely <mark.tinguely@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
If a filesystem has a busted stripe alignment configuration on disk
(e.g. because broken RAID firmware told mkfs that swidth was smaller
than sunit), then the filesystem will refuse to mount due to the
stripe validation failing. This failure is triggering during distro
upgrades from old kernels lacking this check to newer kernels with
this check, and currently the only way to fix it is with offline
xfs_db surgery.
This runtime validity checking occurs when we read the superblock
for the first time and causes the mount to fail immediately. This
prevents the rewrite of stripe unit/width via
mount options that occurs later in the mount process. Hence there is
no way to recover this situation without resorting to offline xfs_db
rewrite of the values.
However, we parse the mount options long before we read the
superblock, and we know if the mount has been asked to re-write the
stripe alignment configuration when we are reading the superblock
and verifying it for the first time. Hence we can conditionally
ignore stripe verification failures if the mount options specified
will correct the issue.
We validate that the new stripe unit/width are valid before we
overwrite the superblock values, so we can ignore the invalid config
at verification and fail the mount later if the new values are not
valid. This, at least, gives users the chance of correcting the
issue after a kernel upgrade without having to resort to xfs-db
hacks.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
* Fix invalid pointer dereference by initializing xmbuf before tracepoint
function is invoked.
* Use memalloc_nofs_save() when inserting into quota radix tree.
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
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Merge tag 'xfs-6.9-merge-9' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull xfs fixes from Chandan Babu:
- Fix invalid pointer dereference by initializing xmbuf before
tracepoint function is invoked
- Use memalloc_nofs_save() when inserting into quota radix tree
* tag 'xfs-6.9-merge-9' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: quota radix tree allocations need to be NOFS on insert
xfs: fix dev_t usage in xmbuf tracepoints
In converting the XFS code from GFP_NOFS to scoped contexts, we
converted the quota radix tree to GFP_KERNEL. Unfortunately, it was
not clearly documented that this set was because there is a
dependency on the quotainfo->qi_tree_lock being taken in memory
reclaim to remove dquots from the radix tree.
In hindsight this is obvious, but the radix tree allocations on
insert are not immediately obvious, and we avoid this for the inode
cache radix trees by using preloading and hence completely avoiding
the radix tree node allocation under tree lock constraints.
Hence there are a few solutions here. The first is to reinstate
GFP_NOFS for the radix tree and add a comment explaining why
GFP_NOFS is used. The second is to use memalloc_nofs_save() on the
radix tree insert context, which makes it obvious that the radix
tree insert runs under GFP_NOFS constraints. The third option is to
simply replace the radix tree and it's lock with an xarray which can
do memory allocation safely in an insert context.
The first is OK, but not really the direction we want to head. The
second is my preferred short term solution. The third - converting
XFS radix trees to xarray - is the longer term solution.
Hence to fix the regression here, we take option 2 as it moves us in
the direction we want to head with memory allocation and GFP_NOFS
removal.
Reported-by: syzbot+8fdff861a781522bda4d@syzkaller.appspotmail.com
Reported-by: syzbot+d247769793ec169e4bf9@syzkaller.appspotmail.com
Fixes: 94a69db236 ("xfs: use __GFP_NOLOCKDEP instead of GFP_NOFS")
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
Fix some inconsistencies in the xmbuf tracepoints -- they should be
reporting the major/minor of the filesystem that they're associated
with, so that we have some clue on whose behalf the xmbuf was created.
Fix the xmbuf_free tracepoint to report the same.
Don't call the trace function until the xmbuf is fully initialized.
Fixes: 5076a6040c ("xfs: support in-memory buffer cache target")
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
* Online Repair;
** New ondisk structures being repaired.
- Inode's mode field by trying to obtain file type value from the a
directory entry.
- Quota counters.
- Link counts of inodes.
- FS summary counters.
- rmap btrees.
Support for in-memory btrees has been added to support repair of rmap
btrees.
** Misc changes
- Report corruption of metadata to the health tracking subsystem.
- Enable indirect health reporting when resources are scarce.
- Reduce memory usage while reparing refcount btree.
- Extend "Bmap update" intent item to support atomic extent swapping on
the realtime device.
- Extend "Bmap update" intent item to support extended attribute fork and
unwritten extents.
** Code cleanups
- Bmap log intent.
- Btree block pointer checking.
- Btree readahead.
- Buffer target.
- Symbolic link code.
* Remove mrlock wrapper around the rwsem.
* Convert all the GFP_NOFS flag usages to use the scoped
memalloc_nofs_save() API instead of direct calls with the GFP_NOFS.
* Refactor and simplify xfile abstraction. Lower level APIs in
shmem.c are required to be exported in order to achieve this.
* Skip checking alignment constraints for inode chunk allocations when block
size is larger than inode chunk size.
* Do not submit delwri buffers collected during log recovery when an error
has been encountered.
* Fix SEEK_HOLE/DATA for file regions which have active COW extents.
* Fix lock order inversion when executing error handling path during
shrinking a filesystem.
* Remove duplicate ifdefs.
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
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Merge tag 'xfs-6.9-merge-8' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull xfs updates from Chandan Babu:
- Online repair updates:
- More ondisk structures being repaired:
- Inode's mode field by trying to obtain file type value from
the a directory entry
- Quota counters
- Link counts of inodes
- FS summary counters
- Support for in-memory btrees has been added to support repair
of rmap btrees
- Misc changes:
- Report corruption of metadata to the health tracking subsystem
- Enable indirect health reporting when resources are scarce
- Reduce memory usage while repairing refcount btree
- Extend "Bmap update" intent item to support atomic extent
swapping on the realtime device
- Extend "Bmap update" intent item to support extended attribute
fork and unwritten extents
- Code cleanups:
- Bmap log intent
- Btree block pointer checking
- Btree readahead
- Buffer target
- Symbolic link code
- Remove mrlock wrapper around the rwsem
- Convert all the GFP_NOFS flag usages to use the scoped
memalloc_nofs_save() API instead of direct calls with the GFP_NOFS
- Refactor and simplify xfile abstraction. Lower level APIs in shmem.c
are required to be exported in order to achieve this
- Skip checking alignment constraints for inode chunk allocations when
block size is larger than inode chunk size
- Do not submit delwri buffers collected during log recovery when an
error has been encountered
- Fix SEEK_HOLE/DATA for file regions which have active COW extents
- Fix lock order inversion when executing error handling path during
shrinking a filesystem
- Remove duplicate ifdefs
* tag 'xfs-6.9-merge-8' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (183 commits)
xfs: shrink failure needs to hold AGI buffer
mm/shmem.c: Use new form of *@param in kernel-doc
kernel-doc: Add unary operator * to $type_param_ref
xfs: use kvfree() in xlog_cil_free_logvec()
xfs: xfs_btree_bload_prep_block() should use __GFP_NOFAIL
xfs: fix scrub stats file permissions
xfs: fix log recovery erroring out on refcount recovery failure
xfs: move symlink target write function to libxfs
xfs: move remote symlink target read function to libxfs
xfs: move xfs_symlink_remote.c declarations to xfs_symlink_remote.h
xfs: xfs_bmap_finish_one should map unwritten extents properly
xfs: support deferred bmap updates on the attr fork
xfs: support recovering bmap intent items targetting realtime extents
xfs: add a realtime flag to the bmap update log redo items
xfs: add a xattr_entry helper
xfs: fix xfs_bunmapi to allow unmapping of partial rt extents
xfs: move xfs_bmap_defer_add to xfs_bmap_item.c
xfs: reuse xfs_bmap_update_cancel_item
xfs: add a bi_entry helper
xfs: remove xfs_trans_set_bmap_flags
...
Yes, yes, I know the slab people were planning on going slow and letting
every subsystem fight this thing on their own. But let's just rip off
the band-aid and get it over and done with. I don't want to see a
number of unnecessary pull requests just to get rid of a flag that no
longer has any meaning.
This was mainly done with a couple of 'sed' scripts and then some manual
cleanup of the end result.
Link: https://lore.kernel.org/all/CAHk-=wji0u+OOtmAOD-5JV3SXcRJF___k_+8XNKmak0yd5vW1Q@mail.gmail.com/
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Merge tag 'vfs-6.9.uuid' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull vfs uuid updates from Christian Brauner:
"This adds two new ioctl()s for getting the filesystem uuid and
retrieving the sysfs path based on the path of a mounted filesystem.
Getting the filesystem uuid has been implemented in filesystem
specific code for a while it's now lifted as a generic ioctl"
* tag 'vfs-6.9.uuid' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
xfs: add support for FS_IOC_GETFSSYSFSPATH
fs: add FS_IOC_GETFSSYSFSPATH
fat: Hook up sb->s_uuid
fs: FS_IOC_GETUUID
ovl: convert to super_set_uuid()
fs: super_set_uuid()
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Merge tag 'vfs-6.9.super' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull block handle updates from Christian Brauner:
"Last cycle we changed opening of block devices, and opening a block
device would return a bdev_handle. This allowed us to implement
support for restricting and forbidding writes to mounted block
devices. It was accompanied by converting and adding helpers to
operate on bdev_handles instead of plain block devices.
That was already a good step forward but ultimately it isn't necessary
to have special purpose helpers for opening block devices internally
that return a bdev_handle.
Fundamentally, opening a block device internally should just be
equivalent to opening files. So now all internal opens of block
devices return files just as a userspace open would. Instead of
introducing a separate indirection into bdev_open_by_*() via struct
bdev_handle bdev_file_open_by_*() is made to just return a struct
file. Opening and closing a block device just becomes equivalent to
opening and closing a file.
This all works well because internally we already have a pseudo fs for
block devices and so opening block devices is simple. There's a few
places where we needed to be careful such as during boot when the
kernel is supposed to mount the rootfs directly without init doing it.
Here we need to take care to ensure that we flush out any asynchronous
file close. That's what we already do for opening, unpacking, and
closing the initramfs. So nothing new here.
The equivalence of opening and closing block devices to regular files
is a win in and of itself. But it also has various other advantages.
We can remove struct bdev_handle completely. Various low-level helpers
are now private to the block layer. Other helpers were simply
removable completely.
A follow-up series that is already reviewed build on this and makes it
possible to remove bdev->bd_inode and allows various clean ups of the
buffer head code as well. All places where we stashed a bdev_handle
now just stash a file and use simple accessors to get to the actual
block device which was already the case for bdev_handle"
* tag 'vfs-6.9.super' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (35 commits)
block: remove bdev_handle completely
block: don't rely on BLK_OPEN_RESTRICT_WRITES when yielding write access
bdev: remove bdev pointer from struct bdev_handle
bdev: make struct bdev_handle private to the block layer
bdev: make bdev_{release, open_by_dev}() private to block layer
bdev: remove bdev_open_by_path()
reiserfs: port block device access to file
ocfs2: port block device access to file
nfs: port block device access to files
jfs: port block device access to file
f2fs: port block device access to files
ext4: port block device access to file
erofs: port device access to file
btrfs: port device access to file
bcachefs: port block device access to file
target: port block device access to file
s390: port block device access to file
nvme: port block device access to file
block2mtd: port device access to files
bcache: port block device access to files
...
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Merge tag 'vfs-6.9.iomap' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull iomap updates from Christian Brauner:
- Restore read-write hints in struct bio through the bi_write_hint
member for the sake of UFS devices in mobile applications. This can
result in up to 40% lower write amplification in UFS devices. The
patch series that builds on this will be coming in via the SCSI
maintainers (Bart)
- Overhaul the iomap writeback code. Afterwards ->map_blocks() is able
to map multiple blocks at once as long as they're in the same folio.
This reduces CPU usage for buffered write workloads on e.g., xfs on
systems with lots of cores (Christoph)
- Record processed bytes in iomap_iter() trace event (Kassey)
- Extend iomap_writepage_map() trace event after Christoph's
->map_block() changes to map mutliple blocks at once (Zhang)
* tag 'vfs-6.9.iomap' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (22 commits)
iomap: Add processed for iomap_iter
iomap: add pos and dirty_len into trace_iomap_writepage_map
block, fs: Restore the per-bio/request data lifetime fields
fs: Propagate write hints to the struct block_device inode
fs: Move enum rw_hint into a new header file
fs: Split fcntl_rw_hint()
fs: Verify write lifetime constants at compile time
fs: Fix rw_hint validation
iomap: pass the length of the dirty region to ->map_blocks
iomap: map multiple blocks at a time
iomap: submit ioends immediately
iomap: factor out a iomap_writepage_map_block helper
iomap: only call mapping_set_error once for each failed bio
iomap: don't chain bios
iomap: move the iomap_sector sector calculation out of iomap_add_to_ioend
iomap: clean up the iomap_alloc_ioend calling convention
iomap: move all remaining per-folio logic into iomap_writepage_map
iomap: factor out a iomap_writepage_handle_eof helper
iomap: move the PF_MEMALLOC check to iomap_writepages
iomap: move the io_folios field out of struct iomap_ioend
...
Chandan reported a AGI/AGF lock order hang on xfs/168 during recent
testing. The cause of the problem was the task running xfs_growfs
to shrink the filesystem. A failure occurred trying to remove the
free space from the btrees that the shrink would make disappear,
and that meant it ran the error handling for a partial failure.
This error path involves restoring the per-ag block reservations,
and that requires calculating the amount of space needed to be
reserved for the free inode btree. The growfs operation hung here:
[18679.536829] down+0x71/0xa0
[18679.537657] xfs_buf_lock+0xa4/0x290 [xfs]
[18679.538731] xfs_buf_find_lock+0xf7/0x4d0 [xfs]
[18679.539920] xfs_buf_lookup.constprop.0+0x289/0x500 [xfs]
[18679.542628] xfs_buf_get_map+0x2b3/0xe40 [xfs]
[18679.547076] xfs_buf_read_map+0xbb/0x900 [xfs]
[18679.562616] xfs_trans_read_buf_map+0x449/0xb10 [xfs]
[18679.569778] xfs_read_agi+0x1cd/0x500 [xfs]
[18679.573126] xfs_ialloc_read_agi+0xc2/0x5b0 [xfs]
[18679.578708] xfs_finobt_calc_reserves+0xe7/0x4d0 [xfs]
[18679.582480] xfs_ag_resv_init+0x2c5/0x490 [xfs]
[18679.586023] xfs_ag_shrink_space+0x736/0xd30 [xfs]
[18679.590730] xfs_growfs_data_private.isra.0+0x55e/0x990 [xfs]
[18679.599764] xfs_growfs_data+0x2f1/0x410 [xfs]
[18679.602212] xfs_file_ioctl+0xd1e/0x1370 [xfs]
trying to get the AGI lock. The AGI lock was held by a fstress task
trying to do an inode allocation, and it was waiting on the AGF
lock to allocate a new inode chunk on disk. Hence deadlock.
The fix for this is for the growfs code to hold the AGI over the
transaction roll it does in the error path. It already holds the AGF
locked across this, and that is what causes the lock order inversion
in the xfs_ag_resv_init() call.
Reported-by: Chandan Babu R <chandanbabu@kernel.org>
Fixes: 46141dc891 ("xfs: introduce xfs_ag_shrink_space()")
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
The xfs_log_vec items are allocated by xlog_kvmalloc(), and so need
to be freed with kvfree. This was missed when coverting from the
kmem_free() API.
Fixes: 4929257613 ("xfs: convert kmem_free() for kvmalloc users to kvfree()")
Reported-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
This was missed in the conversion from KM* flags.
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Fixes: 10634530f7 ("xfs: convert kmem_zalloc() to kzalloc()")
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
FSDAX and reflink can work together now, let's drop this warning.
Signed-off-by: Shiyang Ruan <ruansy.fnst@fujitsu.com>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
When the kernel is in lockdown mode, debugfs will only show files that
are world-readable and cannot be written, mmaped, or used with ioctl.
That more or less describes the scrub stats file, except that the
permissions are wrong -- they should be 0444, not 0644. You can't write
the stats file, so the 0200 makes no sense.
Meanwhile, the clear_stats file is only writable, but it got mode 0400
instead of 0200, which would make more sense.
Fix both files so that they make sense.
Fixes: d7a74cad8f ("xfs: track usage statistics of online fsck")
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
Add two new helpers to allow opening block devices as files.
This is not the final infrastructure. This still opens the block device
before opening a struct a file. Until we have removed all references to
struct bdev_handle we can't switch the order:
* Introduce blk_to_file_flags() to translate from block specific to
flags usable to pen a new file.
* Introduce bdev_file_open_by_{dev,path}().
* Introduce temporary sb_bdev_handle() helper to retrieve a struct
bdev_handle from a block device file and update places that directly
reference struct bdev_handle to rely on it.
* Don't count block device openes against the number of open files. A
bdev_file_open_by_{dev,path}() file is never installed into any
file descriptor table.
One idea that came to mind was to use kernel_tmpfile_open() which
would require us to pass a path and it would then call do_dentry_open()
going through the regular fops->open::blkdev_open() path. But then we're
back to the problem of routing block specific flags such as
BLK_OPEN_RESTRICT_WRITES through the open path and would have to waste
FMODE_* flags every time we add a new one. With this we can avoid using
a flag bit and we have more leeway in how we open block devices from
bdev_open_by_{dev,path}().
Link: https://lore.kernel.org/r/20240123-vfs-bdev-file-v2-1-adbd023e19cc@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
Per the comment in the error case of xfs_reflink_recover_cow, zero out
any error (after shutting down the log) so that we actually kill any new
intent items that might have gotten logged by later recovery steps.
Discovered by xfs/434, which few people actually seem to run.
Fixes: 2c1e31ed5c ("xfs: place intent recovery under NOFS allocation context")
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
Move xfs_symlink_write_target to xfs_symlink_remote.c so that kernel and
mkfs can share the same function.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Move xfs_readlink_bmap_ilocked to xfs_symlink_remote.c so that the
swapext code can use it to convert a remote format symlink back to
shortform format after a metadata repair. While we're at it, fix a
broken printf prefix.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Move declarations for libxfs symlink functions into a separate header
file like we do for most everything else.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
The deferred bmap work state and the log item can transmit unwritten
state, so the XFS_BMAP_MAP handler must map in extents with that
unwritten state.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
The deferred bmap update log item has always supported the attr fork, so
plumb this in so that higher layers can access this.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Now that we have reflink on the realtime device, bmap intent items have
to support remapping extents on the realtime volume.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Extend the bmap update (BUI) log items with a new realtime flag that
indicates that the updates apply against a realtime file's data fork.
We'll wire up the actual code later.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
When XFS_BMAPI_REMAP is passed to bunmapi, that means that we want to
remove part of a block mapping without touching the allocator. For
realtime files with rtextsize > 1, that also means that we should skip
all the code that changes a partial remove request into an unwritten
extent conversion. IOWs, bunmapi in this mode should handle removing
the mapping from the rt file and nothing else.
Note that XFS_BMAPI_REMAP callers are required to decrement the
reference count and/or free the space manually.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Add a helper to translate from the item list head to the attr_intent
item structure and use it so shorten assignments and avoid the need for
extra local variables.
Inspired-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Move the code that adds the incore xfs_bmap_item deferred work data to a
transaction live with the BUI log item code. This means that the file
mapping code no longer has to know about the inner workings of the BUI
log items.
As a consequence, we can hide the _get_group helper.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reuse xfs_bmap_update_cancel_item to put the AG/RTG and free the item in
a few places that currently open code the logic.
Inspired-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Add a helper to translate from the item list head to the bmap_intent
structure and use it so shorten assignments and avoid the need for extra
local variables.
Inspired-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Pass the incore bmap structure to the tracepoints instead of open-coding
the argument passing.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
We're about to start adding support for deferred log intent items for
realtime extents, so split these four types into separate classes so
that we can customize them as the transition happens.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Port the refcount record generating code to use the new refcount bag
data structure.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Create a bag structure for refcount information that uses the refcount
bag btree defined in the previous patch.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Create a new in-memory btree type so that we can store refcount bag info
in a much more memory-efficient and performant format. Recall that the
refcount recordset regenerator computes the new recordset from browsing
the rmap records. Let's say that the rmap records are:
{agbno: 10, length: 40, ...}
{agbno: 11, length: 3, ...}
{agbno: 12, length: 20, ...}
{agbno: 15, length: 1, ...}
It is convenient to have a data structure that could quickly tell us the
refcount for an arbitrary agbno without wasting memory. An array or a
list could do that pretty easily. List suck because of the pointer
overhead. xfarrays are a lot more compact, but we want to minimize
sparse holes in the xfarray to constrain memory usage. Maintaining any
kind of record order isn't needed for correctness, so I created the
"rcbag", which is shorthand for an unordered list of (excerpted) reverse
mappings.
So we add the first rmap to the rcbag, and it looks like:
0: {agbno: 10, length: 40}
The refcount for agbno 10 is 1. Then we move on to block 11, so we add
the second rmap:
0: {agbno: 10, length: 40}
1: {agbno: 11, length: 3}
The refcount for agbno 11 is 2. We move on to block 12, so we add the
third:
0: {agbno: 10, length: 40}
1: {agbno: 11, length: 3}
2: {agbno: 12, length: 20}
The refcount for agbno 12 and 13 is 3. We move on to block 14, and
remove the second rmap:
0: {agbno: 10, length: 40}
1: NULL
2: {agbno: 12, length: 20}
The refcount for agbno 14 is 2. We move on to block 15, and add the
last rmap. But we don't care where it is and we don't want to expand
the array so we put it in slot 1:
0: {agbno: 10, length: 40}
1: {agbno: 15, length: 1}
2: {agbno: 12, length: 20}
The refcount for block 15 is 3. Notice how order doesn't matter in this
list? That's why repair uses an unordered list, or "bag". The data
structure is not a set because it does not guarantee uniqueness.
That said, adding and removing specific items is now an O(n) operation
because we have no idea where that item might be in the list. Overall,
the runtime is O(n^2) which is bad.
I realized that I could easily refactor the btree code and reimplement
the refcount bag with an xfbtree. Adding and removing is now O(log2 n),
so the runtime is at least O(n log2 n), which is much faster. In the
end, the rcbag becomes a sorted list, but that's merely a detail of the
implementation. The repair code doesn't care.
(Note: That horrible xfs_db bmap_inflate command can be used to exercise
this sort of rcbag insanity by cranking up refcounts quickly.)
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Hook the regular rmap code when an rmapbt repair operation is running so
that we can unlock the AGF buffer to scan the filesystem and keep the
in-memory btree up to date during the scan.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Create an in-memory btree of rmap records instead of an array. This
enables us to do live record collection instead of freezing the fs.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Rebuild the reverse mapping btree from all primary metadata. This first
patch establishes the bare mechanics of finding records and putting
together a new ondisk tree; more complex pieces are needed to make it
work properly.
Link: Documentation/filesystems/xfs-online-fsck-design.rst
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
