While the buffered write iomap ops do work due to the fact that zeroing
never allocates blocks, the DAX zeroing should use the direct ops just
like actual DAX I/O.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Link: https://lore.kernel.org/r/20211129102203.2243509-23-hch@lst.de
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Hide the DAX device lookup from the xfs_super.c code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Link: https://lore.kernel.org/r/20211129102203.2243509-22-hch@lst.de
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Unshare the DAX and iomap buffered I/O page zeroing code. This code
previously did a IS_DAX check deep inside the iomap code, which in
fact was the only DAX check in the code. Instead move these checks
into the callers. Most callers already have DAX special casing anyway
and XFS will need it for reflink support as well.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Link: https://lore.kernel.org/r/20211129102203.2243509-19-hch@lst.de
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Add helpers to prepare for using different DAX operations.
Signed-off-by: Shiyang Ruan <ruansy.fnst@fujitsu.com>
[hch: split from a larger patch + slight cleanups]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Link: https://lore.kernel.org/r/20211129102203.2243509-16-hch@lst.de
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Just open code the block size and dax_dev == NULL checks in the callers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com> [erofs]
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Link: https://lore.kernel.org/r/20211129102203.2243509-9-hch@lst.de
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Factor out another DAX setup helper to simplify future changes. Also
move the experimental warning after the checks to not clutter the log
too much if the setup failed.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Link: https://lore.kernel.org/r/20211129102203.2243509-8-hch@lst.de
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The low-level mapping helpers were so far crammed into fs.h. They are
out of place there. The fs.h header should just contain the higher-level
mapping helpers that interact directly with vfs objects such as struct
super_block or struct inode and not the bare mapping helpers. Similarly,
only vfs and specific fs code shall interact with low-level mapping
helpers. And so they won't be made accessible automatically through
regular {g,u}id helpers.
Link: https://lore.kernel.org/r/20211123114227.3124056-3-brauner@kernel.org (v1)
Link: https://lore.kernel.org/r/20211130121032.3753852-3-brauner@kernel.org (v2)
Link: https://lore.kernel.org/r/20211203111707.3901969-3-brauner@kernel.org
Cc: Seth Forshee <sforshee@digitalocean.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
CC: linux-fsdevel@vger.kernel.org
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Seth Forshee <sforshee@digitalocean.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
This ASSERT in xfs_rename is a) incorrect, because
(RENAME_WHITEOUT|RENAME_NOREPLACE) is a valid combination, and
b) unnecessary, because actual invalid flag combinations are already
handled at the vfs level in do_renameat2() before we get called.
So, remove it.
Reported-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
With the remove of xfs_dqrele_all_inodes, xfs_inew_wait and all the
infrastructure used to wake the XFS_INEW bit waitqueue is unused.
Reported-by: kernel test robot <lkp@intel.com>
Fixes: 777eb1fa85 ("xfs: remove xfs_dqrele_all_inodes")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
When testing xfstests xfs/126 on lastest upstream kernel, it will hang on some machine.
Adding a getxattr operation after xattr corrupted, I can reproduce it 100%.
The deadlock as below:
[983.923403] task:setfattr state:D stack: 0 pid:17639 ppid: 14687 flags:0x00000080
[ 983.923405] Call Trace:
[ 983.923410] __schedule+0x2c4/0x700
[ 983.923412] schedule+0x37/0xa0
[ 983.923414] schedule_timeout+0x274/0x300
[ 983.923416] __down+0x9b/0xf0
[ 983.923451] ? xfs_buf_find.isra.29+0x3c8/0x5f0 [xfs]
[ 983.923453] down+0x3b/0x50
[ 983.923471] xfs_buf_lock+0x33/0xf0 [xfs]
[ 983.923490] xfs_buf_find.isra.29+0x3c8/0x5f0 [xfs]
[ 983.923508] xfs_buf_get_map+0x4c/0x320 [xfs]
[ 983.923525] xfs_buf_read_map+0x53/0x310 [xfs]
[ 983.923541] ? xfs_da_read_buf+0xcf/0x120 [xfs]
[ 983.923560] xfs_trans_read_buf_map+0x1cf/0x360 [xfs]
[ 983.923575] ? xfs_da_read_buf+0xcf/0x120 [xfs]
[ 983.923590] xfs_da_read_buf+0xcf/0x120 [xfs]
[ 983.923606] xfs_da3_node_read+0x1f/0x40 [xfs]
[ 983.923621] xfs_da3_node_lookup_int+0x69/0x4a0 [xfs]
[ 983.923624] ? kmem_cache_alloc+0x12e/0x270
[ 983.923637] xfs_attr_node_hasname+0x6e/0xa0 [xfs]
[ 983.923651] xfs_has_attr+0x6e/0xd0 [xfs]
[ 983.923664] xfs_attr_set+0x273/0x320 [xfs]
[ 983.923683] xfs_xattr_set+0x87/0xd0 [xfs]
[ 983.923686] __vfs_removexattr+0x4d/0x60
[ 983.923688] __vfs_removexattr_locked+0xac/0x130
[ 983.923689] vfs_removexattr+0x4e/0xf0
[ 983.923690] removexattr+0x4d/0x80
[ 983.923693] ? __check_object_size+0xa8/0x16b
[ 983.923695] ? strncpy_from_user+0x47/0x1a0
[ 983.923696] ? getname_flags+0x6a/0x1e0
[ 983.923697] ? _cond_resched+0x15/0x30
[ 983.923699] ? __sb_start_write+0x1e/0x70
[ 983.923700] ? mnt_want_write+0x28/0x50
[ 983.923701] path_removexattr+0x9b/0xb0
[ 983.923702] __x64_sys_removexattr+0x17/0x20
[ 983.923704] do_syscall_64+0x5b/0x1a0
[ 983.923705] entry_SYSCALL_64_after_hwframe+0x65/0xca
[ 983.923707] RIP: 0033:0x7f080f10ee1b
When getxattr calls xfs_attr_node_get function, xfs_da3_node_lookup_int fails with EFSCORRUPTED in
xfs_attr_node_hasname because we have use blocktrash to random it in xfs/126. So it
free state in internal and xfs_attr_node_get doesn't do xfs_buf_trans release job.
Then subsequent removexattr will hang because of it.
This bug was introduced by kernel commit 07120f1abd ("xfs: Add xfs_has_attr and subroutines").
It adds xfs_attr_node_hasname helper and said caller will be responsible for freeing the state
in this case. But xfs_attr_node_hasname will free state itself instead of caller if
xfs_da3_node_lookup_int fails.
Fix this bug by moving the step of free state into caller.
Also, use "goto error/out" instead of returning error directly in xfs_attr_node_addname_find_attr and
xfs_attr_node_removename_setup function because we should free state ourselves.
Fixes: 07120f1abd ("xfs: Add xfs_has_attr and subroutines")
Signed-off-by: Yang Xu <xuyang2018.jy@fujitsu.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
* Clean up open-coded swap() calls.
* A little bit of #ifdef golf to complete the reunification of the
kernel and userspace libxfs source code.
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Merge tag 'xfs-5.16-merge-5' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull xfs cleanups from Darrick Wong:
"The most 'exciting' aspect of this branch is that the xfsprogs
maintainer and I have worked through the last of the code
discrepancies between kernel and userspace libxfs such that there are
no code differences between the two except for #includes.
IOWs, diff suffices to demonstrate that the userspace tools behave the
same as the kernel, and kernel-only bits are clearly marked in the
/kernel/ source code instead of just the userspace source.
Summary:
- Clean up open-coded swap() calls.
- A little bit of #ifdef golf to complete the reunification of the
kernel and userspace libxfs source code"
* tag 'xfs-5.16-merge-5' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: sync xfs_btree_split macros with userspace libxfs
xfs: #ifdef out perag code for userspace
xfs: use swap() to make dabtree code cleaner
Sync this one last bit of discrepancy between kernel and userspace
libxfs.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
The xfs_perag structure and initialization is unused in userspace,
so #ifdef it out with __KERNEL__ to facilitate the xfsprogs sync
and build.
Signed-off-by: Eric Sandeen <esandeen@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Use the macro 'swap()' defined in 'include/linux/minmax.h' to avoid
opencoding it.
Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Yang Guang <yang.guang5@zte.com.cn>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
* Bug fixes and cleanups for kernel memory allocation usage, this time
without touching the mm code.
* Refactor the log recovery mechanism that preserves held resources
across a transaction roll so that it uses the exact same mechanism
that we use for that during regular runtime.
* Fix bugs and tighten checking around btree heights.
* Remove more old typedefs.
* Fix perag reference leaks when racing with growfs.
* Remove unused fields from xfs_btree_cur.
* Allocate various scrub structures on the heap to reduce stack usage.
* Pack xfs_btree_cur fields and rearrange to support arbitrary heights.
* Compute maximum possible heights for each btree height, and use that
to set up slab caches for each btree type.
* Finally remove kmem_zone_t, since these have always been struct
kmem_cache on Linux.
* Compact the structures used to coordinate work intent items.
* Set up slab caches for each work intent item type.
* Rename the "bmap_add_free" function to "free_extent_later", which
more accurately describes what it does.
* Fix corruption warning on unmount when a CoW preallocation covers a
data fork delalloc reservation but then the CoW fails.
* Add some more minor code improvements.
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Merge tag 'xfs-5.16-merge-4' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull xfs updates from Darrick Wong:
"This cycle we've worked on fixing bugs and improving XFS' memory
footprint.
The most notable fixes include: fixing a corruption warning (and free
space accounting skew) if copy on write fails; fixing slab cache
misuse if SLOB is enabled, which apparently was broken for years
without anybody noticing; and fixing a potential race with online
shrinkfs.
Otherwise, the bulk of the changes here involve setting up separate
slab caches for frequently used items such as btree cursors and log
intent items, and compacting the structures to reduce memory usage of
those items substantially. This also sets us up to support larger
btrees in future kernels. We also switch parts of online fsck to
allocate scrub context information from the heap instead of using
stack space.
Summary:
- Bug fixes and cleanups for kernel memory allocation usage, this
time without touching the mm code.
- Refactor the log recovery mechanism that preserves held resources
across a transaction roll so that it uses the exact same mechanism
that we use for that during regular runtime.
- Fix bugs and tighten checking around btree heights.
- Remove more old typedefs.
- Fix perag reference leaks when racing with growfs.
- Remove unused fields from xfs_btree_cur.
- Allocate various scrub structures on the heap to reduce stack
usage.
- Pack xfs_btree_cur fields and rearrange to support arbitrary
heights.
- Compute maximum possible heights for each btree height, and use
that to set up slab caches for each btree type.
- Finally remove kmem_zone_t, since these have always been struct
kmem_cache on Linux.
- Compact the structures used to coordinate work intent items.
- Set up slab caches for each work intent item type.
- Rename the "bmap_add_free" function to "free_extent_later", which
more accurately describes what it does.
- Fix corruption warning on unmount when a CoW preallocation covers a
data fork delalloc reservation but then the CoW fails.
- Add some more minor code improvements"
* tag 'xfs-5.16-merge-4' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (45 commits)
xfs: use swap() to make code cleaner
xfs: Remove duplicated include in xfs_super
xfs: punch out data fork delalloc blocks on COW writeback failure
xfs: remove unused parameter from refcount code
xfs: reduce the size of struct xfs_extent_free_item
xfs: rename xfs_bmap_add_free to xfs_free_extent_later
xfs: create slab caches for frequently-used deferred items
xfs: compact deferred intent item structures
xfs: rename _zone variables to _cache
xfs: remove kmem_zone typedef
xfs: use separate btree cursor cache for each btree type
xfs: compute absolute maximum nlevels for each btree type
xfs: kill XFS_BTREE_MAXLEVELS
xfs: compute the maximum height of the rmap btree when reflink enabled
xfs: clean up xfs_btree_{calc_size,compute_maxlevels}
xfs: compute maximum AG btree height for critical reservation calculation
xfs: rename m_ag_maxlevels to m_allocbt_maxlevels
xfs: dynamically allocate cursors based on maxlevels
xfs: encode the max btree height in the cursor
xfs: refactor btree cursor allocation function
...
Functions gfs2_file_read_iter and gfs2_file_write_iter are both
accessing the user buffer to write to or read from while holding the
inode glock. In the most basic scenario, that buffer will not be
resident and it will be mapped to the same file. Accessing the buffer
will trigger a page fault, and gfs2 will deadlock trying to take the
same inode glock again while trying to handle that fault.
Fix that and similar, more complex scenarios by disabling page faults
while accessing user buffers. To make this work, introduce a small
amount of new infrastructure and fix some bugs that didn't trigger so
far, with page faults enabled.
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Merge tag 'gfs2-v5.15-rc5-mmap-fault' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2
Pull gfs2 mmap + page fault deadlocks fixes from Andreas Gruenbacher:
"Functions gfs2_file_read_iter and gfs2_file_write_iter are both
accessing the user buffer to write to or read from while holding the
inode glock.
In the most basic deadlock scenario, that buffer will not be resident
and it will be mapped to the same file. Accessing the buffer will
trigger a page fault, and gfs2 will deadlock trying to take the same
inode glock again while trying to handle that fault.
Fix that and similar, more complex scenarios by disabling page faults
while accessing user buffers. To make this work, introduce a small
amount of new infrastructure and fix some bugs that didn't trigger so
far, with page faults enabled"
* tag 'gfs2-v5.15-rc5-mmap-fault' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
gfs2: Fix mmap + page fault deadlocks for direct I/O
iov_iter: Introduce nofault flag to disable page faults
gup: Introduce FOLL_NOFAULT flag to disable page faults
iomap: Add done_before argument to iomap_dio_rw
iomap: Support partial direct I/O on user copy failures
iomap: Fix iomap_dio_rw return value for user copies
gfs2: Fix mmap + page fault deadlocks for buffered I/O
gfs2: Eliminate ip->i_gh
gfs2: Move the inode glock locking to gfs2_file_buffered_write
gfs2: Introduce flag for glock holder auto-demotion
gfs2: Clean up function may_grant
gfs2: Add wrapper for iomap_file_buffered_write
iov_iter: Introduce fault_in_iov_iter_writeable
iov_iter: Turn iov_iter_fault_in_readable into fault_in_iov_iter_readable
gup: Turn fault_in_pages_{readable,writeable} into fault_in_{readable,writeable}
powerpc/kvm: Fix kvm_use_magic_page
iov_iter: Fix iov_iter_get_pages{,_alloc} page fault return value
Hi Linus,
Please, pull the following hardening fixes and cleanups that I've
been collecting during the last development cycle. All of them have
been baking in linux-next.
Fix -Wcast-function-type error:
- firewire: Remove function callback casts (Oscar Carter)
Fix application of sizeof operator:
- firmware/psci: fix application of sizeof to pointer (jing yangyang)
Replace open coded instances with size_t saturating arithmetic helpers:
- assoc_array: Avoid open coded arithmetic in allocator arguments (Len Baker)
- writeback: prefer struct_size over open coded arithmetic (Len Baker)
- aio: Prefer struct_size over open coded arithmetic (Len Baker)
- dmaengine: pxa_dma: Prefer struct_size over open coded arithmetic (Len Baker)
Flexible array transformation:
- KVM: PPC: Replace zero-length array with flexible array member (Len Baker)
Use 2-factor argument multiplication form:
- nouveau/svm: Use kvcalloc() instead of kvzalloc() (Gustavo A. R. Silva)
- xfs: Use kvcalloc() instead of kvzalloc() (Gustavo A. R. Silva)
Thanks
--
Gustavo
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Merge tag 'kspp-misc-fixes-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux
Pull hardening fixes and cleanups from Gustavo A. R. Silva:
"Various hardening fixes and cleanups that I've been collecting during
the last development cycle:
Fix -Wcast-function-type error:
- firewire: Remove function callback casts (Oscar Carter)
Fix application of sizeof operator:
- firmware/psci: fix application of sizeof to pointer (jing yangyang)
Replace open coded instances with size_t saturating arithmetic
helpers:
- assoc_array: Avoid open coded arithmetic in allocator arguments
(Len Baker)
- writeback: prefer struct_size over open coded arithmetic (Len
Baker)
- aio: Prefer struct_size over open coded arithmetic (Len Baker)
- dmaengine: pxa_dma: Prefer struct_size over open coded arithmetic
(Len Baker)
Flexible array transformation:
- KVM: PPC: Replace zero-length array with flexible array member (Len
Baker)
Use 2-factor argument multiplication form:
- nouveau/svm: Use kvcalloc() instead of kvzalloc() (Gustavo A. R.
Silva)
- xfs: Use kvcalloc() instead of kvzalloc() (Gustavo A. R. Silva)"
* tag 'kspp-misc-fixes-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux:
firewire: Remove function callback casts
nouveau/svm: Use kvcalloc() instead of kvzalloc()
firmware/psci: fix application of sizeof to pointer
dmaengine: pxa_dma: Prefer struct_size over open coded arithmetic
KVM: PPC: Replace zero-length array with flexible array member
aio: Prefer struct_size over open coded arithmetic
writeback: prefer struct_size over open coded arithmetic
xfs: Use kvcalloc() instead of kvzalloc()
assoc_array: Avoid open coded arithmetic in allocator arguments
Use swap() in order to make code cleaner. Issue found by coccinelle.
Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Changcheng Deng <deng.changcheng@zte.com.cn>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Fix following checkincludes.pl warning:
./fs/xfs/xfs_super.c: xfs_btree.h is included more than once.
The include is in line 15. Remove the duplicated here.
Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Add a done_before argument to iomap_dio_rw that indicates how much of
the request has already been transferred. When the request succeeds, we
report that done_before additional bytes were tranferred. This is
useful for finishing a request asynchronously when part of the request
has already been completed synchronously.
We'll use that to allow iomap_dio_rw to be used with page faults
disabled: when a page fault occurs while submitting a request, we
synchronously complete the part of the request that has already been
submitted. The caller can then take care of the page fault and call
iomap_dio_rw again for the rest of the request, passing in the number of
bytes already tranferred.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
If writeback I/O to a COW extent fails, the COW fork blocks are
punched out and the data fork blocks left alone. It is possible for
COW fork blocks to overlap non-shared data fork blocks (due to
cowextsz hint prealloc), however, and writeback unconditionally maps
to the COW fork whenever blocks exist at the corresponding offset of
the page undergoing writeback. This means it's quite possible for a
COW fork extent to overlap delalloc data fork blocks, writeback to
convert and map to the COW fork blocks, writeback to fail, and
finally for ioend completion to cancel the COW fork blocks and leave
stale data fork delalloc blocks around in the inode. The blocks are
effectively stale because writeback failure also discards dirty page
state.
If this occurs, it is likely to trigger assert failures, free space
accounting corruption and failures in unrelated file operations. For
example, a subsequent reflink attempt of the affected file to a new
target file will trip over the stale delalloc in the source file and
fail. Several of these issues are occasionally reproduced by
generic/648, but are reproducible on demand with the right sequence
of operations and timely I/O error injection.
To fix this problem, update the ioend failure path to also punch out
underlying data fork delalloc blocks on I/O error. This is analogous
to the writeback submission failure path in xfs_discard_page() where
we might fail to map data fork delalloc blocks and consistent with
the successful COW writeback completion path, which is responsible
for unmapping from the data fork and remapping in COW fork blocks.
Fixes: 787eb48550 ("xfs: fix and streamline error handling in xfs_end_io")
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
The owner info parameter is always NULL, so get rid of the parameter.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
We only use EFIs to free metadata blocks -- not regular data/attr fork
extents. Remove all the fields that we never use, for a net reduction
of 16 bytes.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
xfs_bmap_add_free isn't a block mapping function; it schedules deferred
freeing operations for a later point in a compound transaction chain.
While it's primarily used by bunmapi, its use has expanded beyond that.
Move it to xfs_alloc.c and rename the function since it's now general
freeing functionality. Bring the slab cache bits in line with the
way we handle the other intent items.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
Create slab caches for the high-level structures that coordinate
deferred intent items, since they're used fairly heavily.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
Rearrange these structs to reduce the amount of unused padding bytes.
This saves eight bytes for each of the three structs changed here, which
means they're now all (rmap/bmap are 64 bytes, refc is 32 bytes) even
powers of two.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
Now that we've gotten rid of the kmem_zone_t typedef, rename the
variables to _cache since that's what they are.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
Remove these typedefs by referencing kmem_cache directly.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
Use 2-factor argument multiplication form kvcalloc() instead of
kvzalloc().
Link: https://github.com/KSPP/linux/issues/162
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Now that we have the infrastructure to track the max possible height of
each btree type, we can create a separate slab cache for cursors of each
type of btree. For smaller indices like the free space btrees, this
means that we can pack more cursors into a slab page, improving slab
utilization.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Add code for all five btree types so that we can compute the absolute
maximum possible btree height for each btree type. This is a setup for
the next patch, which makes every btree type have its own cursor cache.
The functions are exported so that we can have xfs_db report the
absolute maximum btree heights for each btree type, rather than making
everyone run their own ad-hoc computations.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Nobody uses this symbol anymore, so kill it.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Instead of assuming that the hardcoded XFS_BTREE_MAXLEVELS value is big
enough to handle the maximally tall rmap btree when all blocks are in
use and maximally shared, let's compute the maximum height assuming the
rmapbt consumes as many blocks as possible.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
During review of the next patch, Dave remarked that he found these two
btree geometry calculation functions lacking in documentation and that
they performed more work than was really necessary.
These functions take the same parameters and have nearly the same logic;
the only real difference is in the return values. Reword the function
comment to make it clearer what each function does, and move them to be
adjacent to reinforce their relation.
Clean up both of them to stop opencoding the howmany functions, stop
using the uint typedefs, and make them both support computations for
more than 2^32 leaf records, since we're going to need all of the above
for files with large data forks and large rmap btrees.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Compute the actual maximum AG btree height for deciding if a per-AG
block reservation is critically low. This only affects the sanity check
condition, since we /generally/ will trigger on the 10% threshold. This
is a long-winded way of saying that we're removing one more usage of
XFS_BTREE_MAXLEVELS.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Years ago when XFS was thought to be much more simple, we introduced
m_ag_maxlevels to specify the maximum btree height of per-AG btrees for
a given filesystem mount. Then we observed that inode btrees don't
actually have the same height and split that off; and now we have rmap
and refcount btrees with much different geometries and separate
maxlevels variables.
The 'ag' part of the name doesn't make much sense anymore, so rename
this to m_alloc_maxlevels to reinforce that this is the maximum height
of the *free space* btrees. This sets us up for the next patch, which
will add a variable to track the maximum height of all AG btrees.
(Also take the opportunity to improve adjacent comments and fix minor
style problems.)
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
To support future btree code, we need to be able to size btree cursors
dynamically for very large btrees. Switch the maxlevels computation to
use the precomputed values in the superblock, and create cursors that
can handle a certain height. For now, we retain the btree cursor cache
that can handle up to 9-level btrees, though a subsequent patch
introduces separate caches for each btree type, where each cache's
objects will be exactly tall enough to handle the specific btree type.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Encode the maximum btree height in the cursor, since we're soon going to
allow smaller cursors for AG btrees and larger cursors for file btrees.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Refactor btree allocation to a common helper.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reduce the size of the btree cursor structure some more by rearranging
fields to eliminate unused space. While we're at it, fix the ragged
indentation and a spelling error.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Split out the btree level information into a separate struct and put it
at the end of the cursor structure as a VLA. Files with huge data forks
(and in the future, the realtime rmap btree) will require the ability to
support many more levels than a per-AG btree cursor, which means that
we're going to create per-btree type cursor caches to conserve memory
for the more common case.
Note that a subsequent patch actually introduces dynamic cursor heights.
This one merely rearranges the structure to prepare for that.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reorganize struct xchk_btree so that we can dynamically size the context
structure to fit the type of btree cursor that we have. This will
enable us to use memory more efficiently once we start adding very tall
btree types. Right-size the lastkey array to match the number of *node*
levels in the tree so that we stop wasting space.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
The btree scrubbing code checks that the records (or keys) that it finds
in a btree block are all in order by calling the btree cursor's
->recs_inorder function. This of course makes no sense for the first
item in the block, so we switch that off with a separate variable in
struct xchk_btree.
Christoph helped me figure out that the variable is unnecessary, since
we just accessed bc_ptrs[level] and can compare that against zero. Use
that, and save ourselves some memory space.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
We're never going to run more than 4 billion btree operations on a
refcount cursor, so shrink the field to an unsigned int to reduce the
structure size. Fix whitespace alignment too.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
During review of subsequent patches, Dave and I noticed that this
function doesn't work quite right -- accessing cur->bc_ino depends on
the ROOT_IN_INODE flag, not LONG_PTRS. Fix that and the parentheses
isssue. While we're at it, remove the piece that accesses cur->bc_ag,
because block 0 of an AG is never part of a btree.
Note: This changes the btree scrubber tracepoints behavior -- if the
cursor has no buffer for a certain level, it will always report
NULLFSBLOCK. It is assumed that anyone tracing the online fsck code
will also be tracing xchk_start/xchk_done or otherwise be aware of what
exactly is being scrubbed.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
The for_each_perag*() set of macros are hacky in that some (i.e.
those based on sb_agcount) rely on the assumption that perag
iteration terminates naturally with a NULL perag at the specified
end_agno. Others allow for the final AG to have a valid perag and
require the calling function to clean up any potential leftover
xfs_perag reference on termination of the loop.
Aside from providing a subtly inconsistent interface, the former
variant is racy with growfs because growfs can create discoverable
post-eofs perags before the final superblock update that completes
the grow operation and increases sb_agcount. This leads to the
following assert failure (reproduced by xfs/104) in the perag free
path during unmount:
XFS: Assertion failed: atomic_read(&pag->pag_ref) == 0, file: fs/xfs/libxfs/xfs_ag.c, line: 195
This occurs because one of the many for_each_perag() loops in the
code that is expected to terminate with a NULL pag (and thus has no
post-loop xfs_perag_put() check) raced with a growfs and found a
non-NULL post-EOFS perag, but terminated naturally based on the
end_agno check without releasing the post-EOFS perag.
Rework the iteration logic to lift the agno check from the main for
loop conditional to the iteration helper function. The for loop now
purely terminates on a NULL pag and xfs_perag_next() avoids taking a
reference to any perag beyond end_agno in the first place.
Fixes: f250eedcf7 ("xfs: make for_each_perag... a first class citizen")
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
The for_each_perag_from() iteration macro relies on sb_agcount to
process every perag currently within EOFS from a given starting
point. It's perfectly valid to have perag structures beyond
sb_agcount, however, such as if a growfs is in progress. If a perag
loop happens to race with growfs in this manner, it will actually
attempt to process the post-EOFS perag where ->pag_agno ==
sb_agcount. This is reproduced by xfs/104 and manifests as the
following assert failure in superblock write verifier context:
XFS: Assertion failed: agno < mp->m_sb.sb_agcount, file: fs/xfs/libxfs/xfs_types.c, line: 22
Update the corresponding macro to only process perags that are
within the current sb_agcount.
Fixes: 58d43a7e32 ("xfs: pass perags around in fsmap data dev functions")
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Rename the next_agno variable to be consistent across the several
iteration macros and shorten line length.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Fold the loop iteration logic into a helper in preparation for
further fixups. No functional change in this patch.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
coccicheck complains about the use of snprintf() in sysfs show functions.
Fix the coccicheck warning:
WARNING: use scnprintf or sprintf.
Use sysfs_emit instead of scnprintf or sprintf makes more sense.
Signed-off-by: Qing Wang <wangqing@vivo.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Replace the blk_poll interface that requires the caller to keep a queue
and cookie from the submissions with polling based on the bio.
Polling for the bio itself leads to a few advantages:
- the cookie construction can made entirely private in blk-mq.c
- the caller does not need to remember the request_queue and cookie
separately and thus sidesteps their lifetime issues
- keeping the device and the cookie inside the bio allows to trivially
support polling BIOs remapping by stacking drivers
- a lot of code to propagate the cookie back up the submission path can
be removed entirely.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Mark Wunderlich <mark.wunderlich@intel.com>
Link: https://lore.kernel.org/r/20211012111226.760968-15-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Remove the few leftover instances of the xfs_dinode_t typedef.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Remove the few leftover instances of the xfs_dinode_t typedef.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Remove the few leftover instances of the xfs_dinode_t typedef.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Warn if we ever bump nlevels higher than the allowed maximum cursor
height.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
When we're scanning for btree roots to rebuild the AG headers, make sure
that the proposed tree does not exceed the maximum height for that btree
type (and not just XFS_BTREE_MAXLEVELS).
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
Since each btree type has its own precomputed maxlevels variable now,
use them instead of the generic XFS_BTREE_MAXLEVELS to check the level
of each per-AG btree.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
Convert the on-stack scrub context, btree scrub context, and da btree
scrub context into a heap allocation so that we reduce stack usage and
gain the ability to handle tall btrees without issue.
Specifically, this saves us ~208 bytes for the dabtree scrub, ~464 bytes
for the btree scrub, and ~200 bytes for the main scrub context.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Get rid of this old typedef before we start changing other things.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
The btree geometry computation function has an off-by-one error in that
it does not allow maximally tall btrees (nlevels == XFS_BTREE_MAXLEVELS).
This can result in repairs failing unnecessarily on very fragmented
filesystems. Subsequent patches to remove MAXLEVELS usage in favor of
the per-btree type computations will make this a much more likely
occurrence.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
When log recovery tries to recover a transaction that had log intent
items attached to it, it has to save certain parts of the transaction
state (reservation, dfops chain, inodes with no automatic unlock) so
that it can finish single-stepping the recovered transactions before
finishing the chains.
This is done with the xfs_defer_ops_capture and xfs_defer_ops_continue
functions. Right now they open-code this functionality, so let's port
this to the formalized resource capture structure that we introduced in
the previous patch. This enables us to hold up to two inodes and two
buffers during log recovery, the same way we do for regular runtime.
With this patch applied, we'll be ready to support atomic extent swap
which holds two inodes; and logged xattrs which holds one inode and one
xattr leaf buffer.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Transaction users are allowed to flag up to two buffers and two inodes
for ownership preservation across a deferred transaction roll. Hoist
the variables and code responsible for this out of xfs_defer_trans_roll
so that we can use it for the defer capture mechanism.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
For kmalloc() allocations SLOB prepends the blocks with a 4-byte header,
and it puts the size of the allocated blocks in that header.
Blocks allocated with kmem_cache_alloc() allocations do not have that
header.
SLOB explodes when you allocate memory with kmem_cache_alloc() and then
try to free it with kfree() instead of kmem_cache_free().
SLOB will assume that there is a header when there is none, read some
garbage to size variable and corrupt the adjacent objects, which
eventually leads to hang or panic.
Let's make XFS work with SLOB by using proper free function.
Fixes: 9749fee83f ("xfs: enable the xfs_defer mechanism to process extents to free")
Signed-off-by: Rustam Kovhaev <rkovhaev@gmail.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Use 2-factor argument multiplication form kvcalloc() instead of
kvzalloc().
Link: https://github.com/KSPP/linux/issues/162
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
- Fix a race condition in the teardown path of raw mode pmem namespaces.
- Cleanup the code that filesystems use to detect filesystem-dax
capabilities of their underlying block device.
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Merge tag 'libnvdimm-for-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull libnvdimm updates from Dan Williams:
- Fix a race condition in the teardown path of raw mode pmem
namespaces.
- Cleanup the code that filesystems use to detect filesystem-dax
capabilities of their underlying block device.
* tag 'libnvdimm-for-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
dax: remove bdev_dax_supported
xfs: factor out a xfs_buftarg_is_dax helper
dax: stub out dax_supported for !CONFIG_FS_DAX
dax: remove __generic_fsdax_supported
dax: move the dax_read_lock() locking into dax_supported
dax: mark dax_get_by_host static
dm: use fs_dax_get_by_bdev instead of dax_get_by_host
dax: stop using bdevname
fsdax: improve the FS_DAX Kconfig description and help text
libnvdimm/pmem: Fix crash triggered when I/O in-flight during unbind
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Merge tag 'ovl-update-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs
Pull overlayfs update from Miklos Szeredi:
- Copy up immutable/append/sync/noatime attributes (Amir Goldstein)
- Improve performance by enabling RCU lookup.
- Misc fixes and improvements
The reason this touches so many files is that the ->get_acl() method now
gets a "bool rcu" argument. The ->get_acl() API was updated based on
comments from Al and Linus:
Link: https://lore.kernel.org/linux-fsdevel/CAJfpeguQxpd6Wgc0Jd3ks77zcsAv_bn0q17L3VNnnmPKu11t8A@mail.gmail.com/
* tag 'ovl-update-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
ovl: enable RCU'd ->get_acl()
vfs: add rcu argument to ->get_acl() callback
ovl: fix BUG_ON() in may_delete() when called from ovl_cleanup()
ovl: use kvalloc in xattr copy-up
ovl: update ctime when changing fileattr
ovl: skip checking lower file's i_writecount on truncate
ovl: relax lookup error on mismatch origin ftype
ovl: do not set overlay.opaque for new directories
ovl: add ovl_allow_offline_changes() helper
ovl: disable decoding null uuid with redirect_dir
ovl: consistent behavior for immutable/append-only inodes
ovl: copy up sync/noatime fileattr flags
ovl: pass ovl_fs to ovl_check_setxattr()
fs: add generic helper for filling statx attribute flags
- Fix a potential log livelock on busy filesystems when there's so much
work going on that we can't finish a quotaoff before filling up the log
by removing the ability to disable quota accounting.
- Introduce the ability to use per-CPU data structures in XFS so that
we can do a better job of maintaining CPU locality for certain
operations.
- Defer inode inactivation work to per-CPU lists, which will help us
batch that processing. Deletions of large sparse files will *appear*
to run faster, but all that means is that we've moved the work to the
backend.
- Drop the EXPERIMENTAL warnings from the y2038+ support and the inode
btree counters, since it's been nearly a year and no complaints have
come in.
- Remove more of our bespoke kmem* variants in favor of using the
standard Linux calls.
- Prepare for the addition of log incompat features in upcoming cycles
by actually adding code to support this.
- Small cleanups of the xattr code in preparation for landing support
for full logging of extended attribute updates in a future cycle.
- Replace the various log shutdown state and flag code all over xfs
with a single atomic bit flag.
- Fix a serious log recovery bug where log item replay can be skipped
based on the start lsn of a transaction even though the transaction
commit lsn is the key data point for that by enforcing start lsns to
appear in the log in the same order as commit lsns.
- Enable pipelining in the code that pushes log items to disk.
- Drop ->writepage.
- Fix some bugs in GETFSMAP where the last fsmap record reported for a
device could extend beyond the end of the device, and a separate bug
where query keys for one device could be applied to another.
- Don't let GETFSMAP query functions edit their input parameters.
- Small cleanups to the scrub code's handling of perag structures.
- Small cleanups to the incore inode tree walk code.
- Constify btree function parameters that aren't changed, so that there
will never again be confusion about range query functions changing
their input parameters.
- Standardize the format and names of tracepoint data attributes.
- Clean up all the mount state and feature flags to use wrapped bitset
functions instead of inconsistently open-coded flag checks.
- Fix some confusion between xfs_buf hash table key variable vs. block
number.
- Fix a mis-interaction with iomap where we reported shared delalloc
cow fork extents to iomap, which would cause the iomap unshare
operation to return IO errors unnecessarily.
- Fix DONTCACHE behavior.
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Merge tag 'xfs-5.15-merge-6' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull xfs updates from Darrick Wong:
"There's a lot in this cycle.
Starting with bug fixes: To avoid livelocks between the logging code
and the quota code, we've disabled the ability of quotaoff to turn off
quota accounting. (Admins can still disable quota enforcement, but
truly turning off accounting requires a remount.) We've tried to do
this in a careful enough way that there shouldn't be any user visible
effects aside from quotaoff no longer randomly hanging the system.
We've also fixed some bugs in runtime log behavior that could trip up
log recovery if (otherwise unrelated) transactions manage to start and
commit concurrently; some bugs in the GETFSMAP ioctl where we would
incorrectly restrict the range of records output if the two xfs
devices are of different sizes; a bug that resulted in fallocate
funshare failing unnecessarily; and broken behavior in the xfs inode
cache when DONTCACHE is in play.
As for new features: we now batch inode inactivations in percpu
background threads, which sharply decreases frontend thread wait time
when performing file deletions and should improve overall directory
tree deletion times. This eliminates both the problem where closing an
unlinked file (especially on a frozen fs) can stall for a long time,
and should also ease complaints about direct reclaim bogging down on
unlinked file cleanup.
Starting with this release, we've enabled pipelining of the XFS log.
On workloads with high rates of metadata updates to different shards
of the filesystem, multiple threads can be used to format committed
log updates into log checkpoints.
Lastly, with this release, two new features have graduated to
supported status: inode btree counters (for faster mounts), and
support for dates beyond Y2038. Expect these to be enabled by default
in a future release of xfsprogs.
Summary:
- Fix a potential log livelock on busy filesystems when there's so
much work going on that we can't finish a quotaoff before filling
up the log by removing the ability to disable quota accounting.
- Introduce the ability to use per-CPU data structures in XFS so that
we can do a better job of maintaining CPU locality for certain
operations.
- Defer inode inactivation work to per-CPU lists, which will help us
batch that processing. Deletions of large sparse files will
*appear* to run faster, but all that means is that we've moved the
work to the backend.
- Drop the EXPERIMENTAL warnings from the y2038+ support and the
inode btree counters, since it's been nearly a year and no
complaints have come in.
- Remove more of our bespoke kmem* variants in favor of using the
standard Linux calls.
- Prepare for the addition of log incompat features in upcoming
cycles by actually adding code to support this.
- Small cleanups of the xattr code in preparation for landing support
for full logging of extended attribute updates in a future cycle.
- Replace the various log shutdown state and flag code all over xfs
with a single atomic bit flag.
- Fix a serious log recovery bug where log item replay can be skipped
based on the start lsn of a transaction even though the transaction
commit lsn is the key data point for that by enforcing start lsns
to appear in the log in the same order as commit lsns.
- Enable pipelining in the code that pushes log items to disk.
- Drop ->writepage.
- Fix some bugs in GETFSMAP where the last fsmap record reported for
a device could extend beyond the end of the device, and a separate
bug where query keys for one device could be applied to another.
- Don't let GETFSMAP query functions edit their input parameters.
- Small cleanups to the scrub code's handling of perag structures.
- Small cleanups to the incore inode tree walk code.
- Constify btree function parameters that aren't changed, so that
there will never again be confusion about range query functions
changing their input parameters.
- Standardize the format and names of tracepoint data attributes.
- Clean up all the mount state and feature flags to use wrapped
bitset functions instead of inconsistently open-coded flag checks.
- Fix some confusion between xfs_buf hash table key variable vs.
block number.
- Fix a mis-interaction with iomap where we reported shared delalloc
cow fork extents to iomap, which would cause the iomap unshare
operation to return IO errors unnecessarily.
- Fix DONTCACHE behavior"
* tag 'xfs-5.15-merge-6' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (103 commits)
xfs: fix I_DONTCACHE
xfs: only set IOMAP_F_SHARED when providing a srcmap to a write
xfs: fix perag structure refcounting error when scrub fails
xfs: rename buffer cache index variable b_bn
xfs: convert bp->b_bn references to xfs_buf_daddr()
xfs: introduce xfs_buf_daddr()
xfs: kill xfs_sb_version_has_v3inode()
xfs: introduce xfs_sb_is_v5 helper
xfs: remove unused xfs_sb_version_has wrappers
xfs: convert xfs_sb_version_has checks to use mount features
xfs: convert scrub to use mount-based feature checks
xfs: open code sb verifier feature checks
xfs: convert xfs_fs_geometry to use mount feature checks
xfs: replace XFS_FORCED_SHUTDOWN with xfs_is_shutdown
xfs: convert remaining mount flags to state flags
xfs: convert mount flags to features
xfs: consolidate mount option features in m_features
xfs: replace xfs_sb_version checks with feature flag checks
xfs: reflect sb features in xfs_mount
xfs: rework attr2 feature and mount options
...
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Merge tag 'hole_punch_for_v5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs
Pull fs hole punching vs cache filling race fixes from Jan Kara:
"Fix races leading to possible data corruption or stale data exposure
in multiple filesystems when hole punching races with operations such
as readahead.
This is the series I was sending for the last merge window but with
your objection fixed - now filemap_fault() has been modified to take
invalidate_lock only when we need to create new page in the page cache
and / or bring it uptodate"
* tag 'hole_punch_for_v5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
filesystems/locking: fix Malformed table warning
cifs: Fix race between hole punch and page fault
ceph: Fix race between hole punch and page fault
fuse: Convert to using invalidate_lock
f2fs: Convert to using invalidate_lock
zonefs: Convert to using invalidate_lock
xfs: Convert double locking of MMAPLOCK to use VFS helpers
xfs: Convert to use invalidate_lock
xfs: Refactor xfs_isilocked()
ext2: Convert to using invalidate_lock
ext4: Convert to use mapping->invalidate_lock
mm: Add functions to lock invalidate_lock for two mappings
mm: Protect operations adding pages to page cache with invalidate_lock
documentation: Sync file_operations members with reality
mm: Fix comments mentioning i_mutex
All callers already have a dax_device obtained from fs_dax_get_by_bdev
at hand, so just pass that to dax_supported() insted of doing another
lookup.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Link: https://lore.kernel.org/r/20210826135510.6293-10-hch@lst.de
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Refactor the DAX setup code in preparation of removing
bdev_dax_supported.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Link: https://lore.kernel.org/r/20210826135510.6293-9-hch@lst.de
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Yup, the VFS hoist broke it, and nobody noticed. Bulkstat workloads
make it clear that it doesn't work as it should.
Fixes: dae2f8ed79 ("fs: Lift XFS_IDONTCACHE to the VFS layer")
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
While prototyping a free space defragmentation tool, I observed an
unexpected IO error while running a sequence of commands that can be
recreated by the following sequence of commands:
# xfs_io -f -c "pwrite -S 0x58 -b 10m 0 10m" file1
# cp --reflink=always file1 file2
# punch-alternating -o 1 file2
# xfs_io -c "funshare 0 10m" file2
fallocate: Input/output error
I then scraped this (abbreviated) stack trace from dmesg:
WARNING: CPU: 0 PID: 30788 at fs/iomap/buffered-io.c:577 iomap_write_begin+0x376/0x450
CPU: 0 PID: 30788 Comm: xfs_io Not tainted 5.14.0-rc6-xfsx #rc6 5ef57b62a900814b3e4d885c755e9014541c8732
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-1ubuntu1.1 04/01/2014
RIP: 0010:iomap_write_begin+0x376/0x450
RSP: 0018:ffffc90000c0fc20 EFLAGS: 00010297
RAX: 0000000000000001 RBX: ffffc90000c0fd10 RCX: 0000000000001000
RDX: ffffc90000c0fc54 RSI: 000000000000000c RDI: 000000000000000c
RBP: ffff888005d5dbd8 R08: 0000000000102000 R09: ffffc90000c0fc50
R10: 0000000000b00000 R11: 0000000000101000 R12: ffffea0000336c40
R13: 0000000000001000 R14: ffffc90000c0fd10 R15: 0000000000101000
FS: 00007f4b8f62fe40(0000) GS:ffff88803ec00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000056361c554108 CR3: 000000000524e004 CR4: 00000000001706f0
Call Trace:
iomap_unshare_actor+0x95/0x140
iomap_apply+0xfa/0x300
iomap_file_unshare+0x44/0x60
xfs_reflink_unshare+0x50/0x140 [xfs 61947ea9b3a73e79d747dbc1b90205e7987e4195]
xfs_file_fallocate+0x27c/0x610 [xfs 61947ea9b3a73e79d747dbc1b90205e7987e4195]
vfs_fallocate+0x133/0x330
__x64_sys_fallocate+0x3e/0x70
do_syscall_64+0x35/0x80
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f4b8f79140a
Looking at the iomap tracepoints, I saw this:
iomap_iter: dev 8:64 ino 0x100 pos 0 length 0 flags WRITE|0x80 (0x81) ops xfs_buffered_write_iomap_ops caller iomap_file_unshare
iomap_iter_dstmap: dev 8:64 ino 0x100 bdev 8:64 addr -1 offset 0 length 131072 type DELALLOC flags SHARED
iomap_iter_srcmap: dev 8:64 ino 0x100 bdev 8:64 addr 147456 offset 0 length 4096 type MAPPED flags
iomap_iter: dev 8:64 ino 0x100 pos 0 length 4096 flags WRITE|0x80 (0x81) ops xfs_buffered_write_iomap_ops caller iomap_file_unshare
iomap_iter_dstmap: dev 8:64 ino 0x100 bdev 8:64 addr -1 offset 4096 length 4096 type DELALLOC flags SHARED
console: WARNING: CPU: 0 PID: 30788 at fs/iomap/buffered-io.c:577 iomap_write_begin+0x376/0x450
The first time funshare calls ->iomap_begin, xfs sees that the first
block is shared and creates a 128k delalloc reservation in the COW fork.
The delalloc reservation is returned as dstmap, and the shared block is
returned as srcmap. So far so good.
funshare calls ->iomap_begin to try the second block. This time there's
no srcmap (punch-alternating punched it out!) but we still have the
delalloc reservation in the COW fork. Therefore, we again return the
reservation as dstmap and the hole as srcmap. iomap_unshare_iter
incorrectly tries to unshare the hole, which __iomap_write_begin rejects
because shared regions must be fully written and therefore cannot
require zeroing.
Therefore, change the buffered write iomap_begin function not to set
IOMAP_F_SHARED when there isn't a source mapping to read from for the
unsharing.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
The kernel test robot found the following bug when running xfs/355 to
scrub a bmap btree:
XFS: Assertion failed: !sa->pag, file: fs/xfs/scrub/common.c, line: 412
------------[ cut here ]------------
kernel BUG at fs/xfs/xfs_message.c:110!
invalid opcode: 0000 [#1] SMP PTI
CPU: 2 PID: 1415 Comm: xfs_scrub Not tainted 5.14.0-rc4-00021-g48c6615cc557 #1
Hardware name: Hewlett-Packard p6-1451cx/2ADA, BIOS 8.15 02/05/2013
RIP: 0010:assfail+0x23/0x28 [xfs]
RSP: 0018:ffffc9000aacb890 EFLAGS: 00010202
RAX: 0000000000000000 RBX: ffffc9000aacbcc8 RCX: 0000000000000000
RDX: 00000000ffffffc0 RSI: 000000000000000a RDI: ffffffffc09e7dcd
RBP: ffffc9000aacbc80 R08: ffff8881fdf17d50 R09: 0000000000000000
R10: 000000000000000a R11: f000000000000000 R12: 0000000000000000
R13: ffff88820c7ed000 R14: 0000000000000001 R15: ffffc9000aacb980
FS: 00007f185b955700(0000) GS:ffff8881fdf00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7f6ef43000 CR3: 000000020de38002 CR4: 00000000001706e0
Call Trace:
xchk_ag_read_headers+0xda/0x100 [xfs]
xchk_ag_init+0x15/0x40 [xfs]
xchk_btree_check_block_owner+0x76/0x180 [xfs]
xchk_btree_get_block+0xd0/0x140 [xfs]
xchk_btree+0x32e/0x440 [xfs]
xchk_bmap_btree+0xd4/0x140 [xfs]
xchk_bmap+0x1eb/0x3c0 [xfs]
xfs_scrub_metadata+0x227/0x4c0 [xfs]
xfs_ioc_scrub_metadata+0x50/0xc0 [xfs]
xfs_file_ioctl+0x90c/0xc40 [xfs]
__x64_sys_ioctl+0x83/0xc0
do_syscall_64+0x3b/0xc0
The unusual handling of errors while initializing struct xchk_ag is the
root cause here. Since the beginning of xfs_scrub, the goal of
xchk_ag_read_headers has been to read all three AG header buffers and
attach them both to the xchk_ag structure and the scrub transaction.
Corruption errors on any of the three headers doesn't necessarily
trigger an immediate return to userspace, because xfs_scrub can also
tell us to /fix/ the problem.
In other words, it's possible for the xchk_ag init functions to return
an error code and a partially filled out structure so that scrub can use
however much information it managed to pull. Before 5.15, it was
sufficient to cancel (or commit) the scrub transaction on the way out of
the scrub code to release the buffers.
Ccommit 48c6615cc5 added a reference to the perag structure to struct
xchk_ag. Since perag structures are not attached to transactions like
buffers are, this adds the requirement that the perag ref be released
explicitly. The scrub teardown function xchk_teardown was amended to do
this for the xchk_ag embedded in struct xfs_scrub.
Unfortunately, I forgot that certain parts of the scrub code probe
multiple AGs and therefore handle the initialization and cleanup on
their own. Specifically, the bmbt scrubber will initialize it long
enough to cross-reference AG metadata for btree blocks and for the
extent mappings in the bmbt.
If one of the AG headers is corrupt, the init function returns with a
live perag structure reference and some of the AG header buffers. If an
error occurs, the cross referencing will be noted as XCORRUPTion and
skipped, but the main scrub process will move on to the next record.
It is now necessary to release the perag reference before we try to
analyze something from a different AG, or else we'll trip over the
assertion noted above.
Fixes: 48c6615cc5 ("xfs: grab active perag ref when reading AG headers")
Reported-by: kernel test robot <oliver.sang@intel.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
To stop external users from using b_bn as the disk address of the
buffer, rename it to b_rhash_key to indicate that it is the buffer
cache index, not the block number of the buffer. Code that needs the
disk address should use xfs_buf_daddr() to obtain it.
Do the rename and clean up any of the remaining internal b_bn users.
Also clean up any remaining b_bn cruft that is now unused.
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: Darrick J. Wong <djwong@kernel.org>
Stop directly referencing b_bn in code outside the buffer cache, as
b_bn is supposed to be used only as an internal cache index.
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: Darrick J. Wong <djwong@kernel.org>
Introduce a helper function xfs_buf_daddr() to extract the disk
address of the buffer from the struct xfs_buf. This will replace
direct accesses to bp->b_bn and bp->b_maps[0].bm_bn, as well as
the XFS_BUF_ADDR() macro.
This patch introduces the helper function and replaces all uses of
XFS_BUF_ADDR() as this is just a simple sed replacement.
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: Darrick J. Wong <djwong@kernel.org>
All callers to xfs_dinode_good_version() and XFS_DINODE_SIZE() in
both the kernel and userspace have a xfs_mount structure available
which means they can use mount features checks instead looking
directly are the superblock.
Convert these functions to take a mount and use a xfs_has_v3inodes()
check and move it out of the libxfs/xfs_format.h file as it really
doesn't have anything to do with the definition of the on-disk
format.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Rather than open coding XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5
checks everywhere, add a simple wrapper to encapsulate this and make
the code easier to read.
This allows us to remove the xfs_sb_version_has_v3inode() wrapper
which is only used in xfs_format.h now and is just a version number
check.
There are a couple of places where we should be checking the mount
feature bits rather than the superblock version (e.g. remount), so
those are converted to use xfs_has_crc(mp) instead.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
The vast majority of these wrappers are now unused. Remove them
leaving just the small subset of wrappers that are used to either
add feature bits or make the mount features field setup code
simpler.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
This is a conversion of the remaining xfs_sb_version_has..(sbp)
checks to use xfs_has_..(mp) feature checks.
This was largely done with a vim replacement macro that did:
:0,$s/xfs_sb_version_has\(.*\)&\(.*\)->m_sb/xfs_has_\1\2/g<CR>
A couple of other variants were also used, and the rest touched up
by hand.
$ size -t fs/xfs/built-in.a
text data bss dec hex filename
before 1127533 311352 484 1439369 15f689 (TOTALS)
after 1125360 311352 484 1437196 15ee0c (TOTALS)
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
The scrub feature checks are the last place that the superblock
feature checks are used. Convert them to mount based feature checks.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
The superblock verifiers are one of the last places that use the sb
version functions to do feature checks. This are all quite simple
uses, and there aren't many of them so open code them all.
Also, move the good version number check into xfs_sb.c instead of it
being an inline function in xfs_format.h
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reporting filesystem features to userspace is currently superblock
based. Now we have a general mount-based feature infrastructure,
switch to using the xfs_mount rather than the superblock directly.
This reduces the size of the function by over 300 bytes.
$ size -t fs/xfs/built-in.a
text data bss dec hex filename
before 1127855 311352 484 1439691 15f7cb (TOTALS)
after 1127535 311352 484 1439371 15f68b (TOTALS)
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: Darrick J. Wong <djwong@kernel.org>
Remove the shouty macro and instead use the inline function that
matches other state/feature check wrapper naming. This conversion
was done with sed.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
The remaining mount flags kept in m_flags are actually runtime state
flags. These change dynamically, so they really should be updated
atomically so we don't potentially lose an update due to racing
modifications.
Convert these remaining flags to be stored in m_opstate and use
atomic bitops to set and clear the flags. This also adds a couple of
simple wrappers for common state checks - read only and shutdown.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Replace m_flags feature checks with xfs_has_<feature>() calls and
rework the setup code to set flags in m_features.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
This provides separation of mount time feature flags from runtime
mount flags and mount option state. It also makes the feature
checks use the same interface as the superblock features. i.e. we
don't care if the feature is enabled by superblock flags or mount
options, we just care if it's enabled or not.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Convert the xfs_sb_version_hasfoo() to checks against
mp->m_features. Checks of the superblock itself during disk
operations (e.g. in the read/write verifiers and the to/from disk
formatters) are not converted - they operate purely on the
superblock state. Everything else should use the mount features.
Large parts of this conversion were done with sed with commands like
this:
for f in `git grep -l xfs_sb_version_has fs/xfs/*.c`; do
sed -i -e 's/xfs_sb_version_has\(.*\)(&\(.*\)->m_sb)/xfs_has_\1(\2)/' $f
done
With manual cleanups for things like "xfs_has_extflgbit" and other
little inconsistencies in naming.
The result is ia lot less typing to check features and an XFS binary
size reduced by a bit over 3kB:
$ size -t fs/xfs/built-in.a
text data bss dec hex filenam
before 1130866 311352 484 1442702 16038e (TOTALS)
after 1127727 311352 484 1439563 15f74b (TOTALS)
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: Darrick J. Wong <djwong@kernel.org>
Currently on-disk feature checks require decoding the superblock
fileds and so can be non-trivial. We have almost 400 hundred
individual feature checks in the XFS code, so this is a significant
amount of code. To reduce runtime check overhead, pre-process all
the version flags into a features field in the xfs_mount at mount
time so we can convert all the feature checks to a simple flag
check.
There is also a need to convert the dynamic feature flags to update
the m_features field. This is required for attr, attr2 and quota
features. New xfs_mount based wrappers are added for this.
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: Darrick J. Wong <djwong@kernel.org>
The attr2 feature is somewhat unique in that it has both a superblock
feature bit to enable it and mount options to enable and disable it.
Back when it was first introduced in 2005, attr2 was disabled unless
either the attr2 superblock feature bit was set, or the attr2 mount
option was set. If the superblock feature bit was not set but the
mount option was set, then when the first attr2 format inode fork
was created, it would set the superblock feature bit. This is as it
should be - the superblock feature bit indicated the presence of the
attr2 on disk format.
The noattr2 mount option, however, did not affect the superblock
feature bit. If noattr2 was specified, the on-disk superblock
feature bit was ignored and the code always just created attr1
format inode forks. If neither of the attr2 or noattr2 mounts
option were specified, then the behaviour was determined by the
superblock feature bit.
This was all pretty sane.
Fast foward 3 years, and we are dealing with fallout from the
botched sb_features2 addition and having to deal with feature
mismatches between the sb_features2 and sb_bad_features2 fields. The
attr2 feature bit was one of these flags. The reconciliation was
done well after mount option parsing and, unfortunately, the feature
reconciliation had a bug where it ignored the noattr2 mount option.
For reasons lost to the mists of time, it was decided that resolving
this issue in commit 7c12f29650 ("[XFS] Fix up noattr2 so that it
will properly update the versionnum and features2 fields.") required
noattr2 to clear the superblock attr2 feature bit. This greatly
complicated the attr2 behaviour and broke rules about feature bits
needing to be set when those specific features are present in the
filesystem.
By complicated, I mean that it introduced problems due to feature
bit interactions with log recovery. All of the superblock feature
bit checks are done prior to log recovery, but if we crash after
removing a feature bit, then on the next mount we see the feature
bit in the unrecovered superblock, only to have it go away after the
log has been replayed. This means our mount time feature processing
could be all wrong.
Hence you can mount with noattr2, crash shortly afterwards, and
mount again without attr2 or noattr2 and still have attr2 enabled
because the second mount sees attr2 still enabled in the superblock
before recovery runs and removes the feature bit. It's just a mess.
Further, this is all legacy code as the v5 format requires attr2 to
be enabled at all times and it cannot be disabled. i.e. the noattr2
mount option returns an error when used on v5 format filesystems.
To straighten this all out, this patch reverts the attr2/noattr2
mount option behaviour back to the original behaviour. There is no
reason for disabling attr2 these days, so we will only do this when
the noattr2 mount option is set. This will not remove the superblock
feature bit. The superblock bit will provide the default behaviour
and only track whether attr2 is present on disk or not. The attr2
mount option will enable the creation of attr2 format inode forks,
and if the superblock feature bit is not set it will be added when
the first attr2 inode fork is created.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
xfs_has_attr() is poorly named. It has global scope as it is defined
in a header file, but it has no namespace scope that tells us what
it is checking has attributes. It's not even clear what "has_attr"
means, because what it is actually doing is an attribute fork lookup
to see if the attribute exists.
Upcoming patches use this "xfs_has_<foo>" namespace for global
filesystem features, which conflicts with this function.
Rename xfs_has_attr() to xfs_attr_lookup() and make it a static
function, freeing up the "xfs_has_" namespace for global scope
usage.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
The verifier checks explicitly for bp->b_bn == XFS_SB_DADDR to match
the primary superblock buffer, but the primary superblock is an
uncached buffer and so bp->b_bn is always -1ULL. Hence this never
matches and the CRC error reporting is wholly dependent on the
mount superblock already being populated so CRC feature checks pass
and allow CRC errors to be reported.
Fix this so that the primary superblock CRC error reporting is not
dependent on already having read the superblock into memory.
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: Darrick J. Wong <djwong@kernel.org>
Because there are a lot of tracepoints that express numeric data with
an associated unit and tag, document what they are to help everyone else
keep these thigns straight.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
When using pretty-printed scrub tracepoints, decode the meaning of the
scrub flags as strings for easier reading.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Always print inode generation in hexadecimal and preceded with the unit
"gen".
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
For the remaining xfs_buf tracepoints, convert all the tags to
xfs_daddr_t units and retag them 'daddrcount' to match everything else.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Emit whichfork values as text strings in the ftrace output.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Whenever we record i_disk_size (i.e. the ondisk file size), use the
"disize" tag and hexadecimal format consistently.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Some of our tracepoints have a field known as "count". That name
doesn't describe any units, which makes the fields not very useful.
Rename the fields to capture units and ensure the format is hexadecimal
when we're referring to blocks, extents, or IO operations.
"fsbcount" are in units of fs blocks
"bytecount" are in units of bytes
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Some of our tracepoints have a field known as "len". That name doesn't
describe any units, which makes the fields not very useful. Rename the
fields to capture units and ensure the format is hexadecimal.
"fsbcount" are in units of fs blocks
"bbcount" are in units of 512b blocks
"ireccount" are in units of inodes
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Some of our tracepoints describe fields as "offset". That name doesn't
describe any units, which makes the fields not very useful. Rename the
fields to capture units and ensure the format is hexadecimal.
"fileoff" means file offset, in units of fs blocks
"pos" means file offset, in bytes
"forkoff" means inode fork offset, in bytes
The one remaining "offset" value is for iclogs, since that's the byte
offset of the end of where we've written into the current iclog.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Some of our tracepoints describe fields as "blkno", "block", or "bno".
That name doesn't describe any units, which makes the fields not very
useful. Rename the fields to capture units and ensure the format is
hexadecimal.
"startblock" is the startblock field from the bmap structure, which is a
segmented fsblock on the data device, or an rfsblock on the realtime
device.
"fileoff" is a file offset, in units of filesystem blocks
"daddr" is a raw device offset, in 512b blocks
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Always print disk addr (i.e. 512 byte block) numbers in hexadecimal and
preceded with the unit "daddr".
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Always print rmap owner number in hexadecimal and preceded with the unit
"owner".
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Always print allocation group block numbers in hexadecimal and preceded
with the unit "agbno".
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Always print allocation group numbers in hexadecimal and preceded with
the unit "agno".
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Always print inode numbers in hexadecimal and preceded with the unit
"ino" or "agino", as apropriate. Fix one tracepoint that used "ino %u"
for an inode btree block count to reduce confusion.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
XFS_DADDR_TO_FSB converts a raw disk address (in units of 512b blocks)
to a raw disk address (in units of fs blocks). Unfortunately, the
xchk_block_error_class tracepoints incorrectly uses this to decode
xfs_daddr_t into segmented AG number and AG block addresses. Use the
correct translation code.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
With quotaoff not allowing disabling of accounting there is no need
for untagged lookups in this code, so remove the dead leftovers.
Repoted-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
[djwong: convert to for_each_perag_tag]
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Constify the rest of the btree functions that take structure and union
pointers and are not supposed to modify them.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
This btree function is called when updating a record in the rightmost
block of a btree so that we can update the AGF's longest free extent
length field. Neither parameter is supposed to be updated, so mark them
both const.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
The @start pointer passed to each per-AG btree type's ->alloc_block
function isn't supposed to be modified, since it's a hint about the
location of the btree block being split that is to be fed to the
allocator, so mark the parameter const.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
The pointer passed to each per-AG btree type's ->set_root function isn't
supposed to be modified (that function sets an external pointer to the
root block) so mark them const.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
xchk_btree calls a user-supplied function to validate each btree record
that it finds. Those functions are not supposed to change the record
data, so mark the parameter const.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
The inorder functions are simple predicates, which means that they don't
modify the parameters. Mark them all const.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
These functions initialize a key from a record, but they aren't supposed
to modify the record. Mark it const.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
The query_range functions are supposed to call a caller-supplied
function on each record found in the dataset. These functions don't
own the memory storing the record, so don't let them change the record.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Range query functions are not supposed to modify the query keys that are
being passed in, so mark them all const.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
The btree key comparison functions are not allowed to change the keys
that are passed in, so mark them const. We'll need this for the next
patch, which adds const to the btree range query functions.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Add a tracepoint for fs shutdowns so we can capture that in ftrace
output.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Now that we always grab an active reference to a perag structure when
dealing with perag metadata, we can remove this unnecessary variable.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
There are several GETFSMAP backend functions for XFS to cover the three
devices and various feature support. Each of these functions are passed
pointers to the low and high keys for the dataset that userspace
requested, and a pointer to scratchpad variables that are used to
control the iteration and fill out records. The scratchpad data can be
changed arbitrarily, but the keys are supposed to remain unchanged (and
under the control of the outermost loop in xfs_getfsmap).
Unfortunately, the data and rt backends modify the keys that are passed
in from the main control loop, which causes subsequent calls to return
incorrect query results. Specifically, each of those two functions set
the block number in the high key to the size of their respective device.
Since fsmap results are sorted in device number order, if the lower
numbered device is smaller than the higher numbered device, the first
function will set the high key to the small size, and the key remains
unchanged as it is passed into the function for the higher numbered
device. The second function will then fail to return all of the results
for the dataset that userspace is asking for because the keyspace is
incorrectly constrained.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
The fsmap implementation for realtime devices uses the gap between
info->next_daddr and a free rtextent reported by xfs_rtalloc_query_range
to feed userspace fsmap records with an "unknown" owner. We use this
trick to report to userspace when the last rtextent in the filesystem is
in use by synthesizing a null rmap record starting at the next block
after the query range.
Unfortunately, there's a minor accounting bug in the way that we
construct the null rmap record. Originally, ahigh.ar_startext contains
the last rtextent for which the user wants records. It's entirely
possible that number is beyond the end of the rt volume, so the location
synthesized rmap record /must/ be constrained to the minimum of the high
key and the number of extents in the rt volume.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
In commit 8ad560d256, we changed xfs_rtalloc_query_range to constrain
the range of bits in the realtime bitmap file that would actually be
searched. In commit a3a374bf18, we changed the range again
(incorrectly), leading to the fix in commit d88850bd55, which finally
corrected the range check code. Unfortunately, the author never noticed
that the function modifies its input parameters, which is a totaly no-no
since none of the other range query functions change their input
parameters.
So, fix this function yet again to stash the upper end of the query
range (i.e. the high key) in a local variable and hope this is the last
time I have to fix my own function. While we're at it, mark the key
inputs const so nobody makes this mistake again. :(
Fixes: 8ad560d256 ("xfs: strengthen rtalloc query range checks")
Not-fixed-by: a3a374bf18 ("xfs: fix off-by-one error in xfs_rtalloc_query_range")
Not-fixed-by: d88850bd55 ("xfs: fix high key handling in the rt allocator's query_range function")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
->writepage is only used in one place - single page writeback from
memory reclaim. We only allow such writeback from kswapd, not from
direct memory reclaim, and so it is rarely used. When it comes from
kswapd, it is effectively random dirty page shoot-down, which is
horrible for IO patterns. We will already have background writeback
trying to clean all the dirty pages in memory as efficiently as
possible, so having kswapd interrupt our well formed IO stream only
slows things down. So get rid of xfs_vm_writepage() completely.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
[djwong: forward port to 5.15]
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Add a rcu argument to the ->get_acl() callback to allow
get_cached_acl_rcu() to call the ->get_acl() method in the next patch.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
We only use the CIL workqueue in the CIL, so it makes no sense to
hang it off the xfs_mount and have to walk multiple pointers back up
to the mount when we have the CIL structures right there.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Because we use a single work structure attached to the CIL rather
than the CIL context, we can only queue a single work item at a
time. This results in the CIL being single threaded and limits
performance when it becomes CPU bound.
The design of the CIL is that it is pipelined and multiple commits
can be running concurrently, but the way the work is currently
implemented means that it is not pipelining as it was intended. The
critical work to switch the CIL context can take a few milliseconds
to run, but the rest of the CIL context flush can take hundreds of
milliseconds to complete. The context switching is the serialisation
point of the CIL, once the context has been switched the rest of the
context push can run asynchrnously with all other context pushes.
Hence we can move the work to the CIL context so that we can run
multiple CIL pushes at the same time and spread the majority of
the work out over multiple CPUs. We can keep the per-cpu CIL commit
state on the CIL rather than the context, because the context is
pinned to the CIL until the switch is done and we aggregate and
drain the per-cpu state held on the CIL during the context switch.
However, because we no longer serialise the CIL work, we can have
effectively unlimited CIL pushes in progress. We don't want to do
this - not only does it create contention on the iclogs and the
state machine locks, we can run the log right out of space with
outstanding pushes. Instead, limit the work concurrency to 4
concurrent works being processed at a time. This is enough
concurrency to remove the CIL from being a CPU bound bottleneck but
not enough to create new contention points or unbound concurrency
issues.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.
As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:
....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....
In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.
Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.
The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.
Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.
We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.
One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Because log recovery depends on strictly ordered start records as
well as strictly ordered commit records.
This is a zero day bug in the way XFS writes pipelined transactions
to the journal which is exposed by fixing the zero day bug that
prevents the CIL from pipelining checkpoints. This re-introduces
explicit concurrent commits back into the on-disk journal and hence
out of order start records.
The XFS journal commit code has never ordered start records and we
have relied on strict commit record ordering for correct recovery
ordering of concurrently written transactions. Unfortunately, root
cause analysis uncovered the fact that log recovery uses the LSN of
the start record for transaction commit processing. Hence, whilst
the commits are processed in strict order by recovery, the LSNs
associated with the commits can be out of order and so recovery may
stamp incorrect LSNs into objects and/or misorder intents in the AIL
for later processing. This can result in log recovery failures
and/or on disk corruption, sometimes silent.
Because this is a long standing log recovery issue, we can't just
fix log recovery and call it good. This still leaves older kernels
susceptible to recovery failures and corruption when replaying a log
from a kernel that pipelines checkpoints. There is also the issue
that in-memory ordering for AIL pushing and data integrity
operations are based on checkpoint start LSNs, and if the start LSN
is incorrect in the journal, it is also incorrect in memory.
Hence there's really only one choice for fixing this zero-day bug:
we need to strictly order checkpoint start records in ascending
sequence order in the log, the same way we already strictly order
commit records.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Now that we have a mechanism to guarantee that the callbacks
attached to an iclog are owned by the context that attaches them
until they drop their reference to the iclog via
xlog_state_release_iclog(), we can attach callbacks to the iclog at
any time we have an active reference to the iclog.
xlog_state_get_iclog_space() always guarantees that the commit
record will fit in the iclog it returns, so we can move this IO
callback setting to xlog_cil_set_ctx_write_state(), record the
commit iclog in the context and remove the need for the commit iclog
to be returned by xlog_write() altogether.
This, in turn, allows us to move the wakeup for ordered commit
record writes up into xlog_cil_set_ctx_write_state(), too, because
we have been guaranteed that this commit record will be physically
located in the iclog before any waiting commit record at a higher
sequence number will be granted iclog space.
This further cleans up the post commit record write processing in
the CIL push code, especially as xlog_state_release_iclog() will now
clean up the context when shutdown errors occur.
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: Darrick J. Wong <djwong@kernel.org>
So we can use it for start record ordering as well as commit record
ordering in future.
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: Darrick J. Wong <djwong@kernel.org>
Pass the CIL context to xlog_write() rather than a pointer to a LSN
variable. Only the CIL checkpoint calls to xlog_write() need to know
about the start LSN of the writes, so rework xlog_write to directly
write the LSNs into the CIL context structure.
This removes the commit_lsn variable from xlog_cil_push_work(), so
now we only have to issue the commit record ordering wakeup from
there.
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: Darrick J. Wong <djwong@kernel.org>
It is only used by the CIL checkpoints, and is the counterpart to
start record formatting and writing that is already local to
xfs_log_cil.c.
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: Darrick J. Wong <djwong@kernel.org>
I'm seeing assert failures from xlog_space_left() after a shutdown
has begun that look like:
XFS (dm-0): log I/O error -5
XFS (dm-0): xfs_do_force_shutdown(0x2) called from line 1338 of file fs/xfs/xfs_log.c. Return address = xlog_ioend_work+0x64/0xc0
XFS (dm-0): Log I/O Error Detected.
XFS (dm-0): Shutting down filesystem. Please unmount the filesystem and rectify the problem(s)
XFS (dm-0): xlog_space_left: head behind tail
XFS (dm-0): tail_cycle = 6, tail_bytes = 2706944
XFS (dm-0): GH cycle = 6, GH bytes = 1633867
XFS: Assertion failed: 0, file: fs/xfs/xfs_log.c, line: 1310
------------[ cut here ]------------
Call Trace:
xlog_space_left+0xc3/0x110
xlog_grant_push_threshold+0x3f/0xf0
xlog_grant_push_ail+0x12/0x40
xfs_log_reserve+0xd2/0x270
? __might_sleep+0x4b/0x80
xfs_trans_reserve+0x18b/0x260
.....
There are two things here. Firstly, after a shutdown, the log head
and tail can be out of whack as things abort and release (or don't
release) resources, so checking them for sanity doesn't make much
sense. Secondly, xfs_log_reserve() can race with shutdown and so it
can still fail like this even though it has already checked for a
log shutdown before calling xlog_grant_push_ail().
So, before ASSERT failing in xlog_space_left(), make sure we haven't
already shut down....
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: Darrick J. Wong <djwong@kernel.org>
When the log is shutdown, it currently walks all the iclogs and runs
callbacks that are attached to the iclogs, regardless of whether the
iclog is queued for IO completion or not. This creates a problem for
contexts attaching callbacks to iclogs in that a racing shutdown can
run the callbacks even before the attaching context has finished
processing the iclog and releasing it for IO submission.
If the callback processing of the iclog frees the structure that is
attached to the iclog, then this leads to an UAF scenario that can
only be protected against by holding the icloglock from the point
callbacks are attached through to the release of the iclog. While we
currently do this, it is not practical or sustainable.
Hence we need to make shutdown processing the responsibility of the
context that holds active references to the iclog. We know that the
contexts attaching callbacks to the iclog must have active
references to the iclog, and that means they must be in either
ACTIVE or WANT_SYNC states. xlog_state_do_callback() will skip over
iclogs in these states -except- when the log is shut down.
xlog_state_do_callback() checks the state of the iclogs while
holding the icloglock, therefore the reference count/state change
that occurs in xlog_state_release_iclog() after the callbacks are
atomic w.r.t. shutdown processing.
We can't push the responsibility of callback cleanup onto the CIL
context because we can have ACTIVE iclogs that have callbacks
attached that have already been released. Hence we really need to
internalise the cleanup of callbacks into xlog_state_release_iclog()
processing.
Indeed, we already have that internalisation via:
xlog_state_release_iclog
drop last reference
->SYNCING
xlog_sync
xlog_write_iclog
if (log_is_shutdown)
xlog_state_done_syncing()
xlog_state_do_callback()
<process shutdown on iclog that is now in SYNCING state>
The problem is that xlog_state_release_iclog() aborts before doing
anything if the log is already shut down. It assumes that the
callbacks have already been cleaned up, and it doesn't need to do
any cleanup.
Hence the fix is to remove the xlog_is_shutdown() check from
xlog_state_release_iclog() so that reference counts are correctly
released from the iclogs, and when the reference count is zero we
always transition to SYNCING if the log is shut down. Hence we'll
always enter the xlog_sync() path in a shutdown and eventually end
up erroring out the iclog IO and running xlog_state_do_callback() to
process the callbacks attached to the iclog.
This allows us to stop processing referenced ACTIVE/WANT_SYNC iclogs
directly in the shutdown code, and in doing so gets rid of the UAF
vector that currently exists. This then decouples the adding of
callbacks to the iclogs from xlog_state_release_iclog() as we
guarantee that xlog_state_release_iclog() will process the callbacks
if the log has been shut down before xlog_state_release_iclog() has
been called.
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: Darrick J. Wong <djwong@kernel.org>
The iclog callback processing done during a forced log shutdown has
different logic to normal runtime IO completion callback processing.
Separate out the shutdown callbacks into their own function and call
that from the shutdown code instead.
We don't need this shutdown specific logic in the normal runtime
completion code - we'll always run the shutdown version on shutdown,
and it will do what shutdown needs regardless of whether there are
racing IO completion callbacks scheduled or in progress. Hence we
can also simplify the normal IO completion callpath and only abort
if shutdown occurred while we actively were processing callbacks.
Further, separating out the IO completion logic from the shutdown
logic avoids callback race conditions from being triggered by log IO
completion after a shutdown. IO completion will now only run
callbacks on iclogs that are in the correct state for a callback to
be run, avoiding the possibility of running callbacks on a
referenced iclog that hasn't yet been submitted for IO.
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: Darrick J. Wong <djwong@kernel.org>
Clean it up a bit by factoring and rearranging some of the code.
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: Darrick J. Wong <djwong@kernel.org>
The running of a forced shutdown is a bit of a mess. It does racy
checks for XFS_MOUNT_SHUTDOWN in xfs_do_force_shutdown(), then
does more racy checks in xfs_log_force_unmount() before finally
setting XFS_MOUNT_SHUTDOWN and XLOG_IO_ERROR under the
log->icloglock.
Move the checking and setting of XFS_MOUNT_SHUTDOWN into
xfs_do_force_shutdown() so we only process a shutdown once and once
only. Serialise this with the mp->m_sb_lock spinlock so that the
state change is atomic and won't race. Move all the mount specific
shutdown state changes from xfs_log_force_unmount() to
xfs_do_force_shutdown() so they are done atomically with setting
XFS_MOUNT_SHUTDOWN.
Then get rid of the racy xlog_is_shutdown() check from
xlog_force_shutdown(), and gate the log shutdown on the
test_and_set_bit(XLOG_IO_ERROR) test under the icloglock. This
means that the log is shutdown once and once only, and code that
needs to prevent races with shutdown can do so by holding the
icloglock and checking the return value of xlog_is_shutdown().
This results in a predictable shutdown execution process - we set the
shutdown flags once and process the shutdown once rather than the
current "as many concurrent shutdowns as can race to the flag
setting" situation we have now.
Also, now that shutdown is atomic, alway emit a stack trace when the
error level for the filesystem is high enough. This means that we
always get a stack trace when trying to diagnose the cause of
shutdowns in the field, rather than just for SHUTDOWN_CORRUPT_INCORE
cases.
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: Darrick J. Wong <djwong@kernel.org>
log->l_flags doesn't actually contain "flags" as such, it contains
operational state information that can change at runtime. For the
shutdown state, this at least should be an atomic bit because
it is read without holding locks in many places and so using atomic
bitops for the state field modifications makes sense.
This allows us to use things like test_and_set_bit() on state
changes (e.g. setting XLOG_TAIL_WARN) to avoid races in setting the
state when we aren't holding locks.
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: Darrick J. Wong <djwong@kernel.org>
xfs_log_mount_finish() needs to know if recovery is needed or not to
make decisions on whether to flush the log and AIL. Move the
handling of the NEED_RECOVERY state out to this function rather than
needing a temporary variable to store this state over the call to
xlog_recover_finish().
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: Darrick J. Wong <djwong@kernel.org>
We don't need an iclog state field to tell us the log has been shut
down. We can just check the xlog_is_shutdown() instead. The avoids
the need to have shutdown overwrite the current iclog state while
being active used by the log code and so having to ensure that every
iclog state check handles XLOG_STATE_IOERROR appropriately.
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: Darrick J. Wong <djwong@kernel.org>
Make it less shouty and a static inline before adding more calls
through the log code.
Also convert internal log code that uses XFS_FORCED_SHUTDOWN(mount)
to use xlog_is_shutdown(log) as well.
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: Darrick J. Wong <djwong@kernel.org>
__FUNCTION__ exists only for backwards compatibility reasons
with old gcc versions. Replace it with __func__.
Signed-off-by: Dwaipayan Ray <dwaipayanray1@gmail.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Now that xfs_attr_rmtval_remove is gone, rename __xfs_attr_rmtval_remove
to xfs_attr_rmtval_remove
Signed-off-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
This is a quick patch to add a new xfs_attr_*_return tracepoints. We
use these to track when ever a new state is set or -EAGAIN is returned
Signed-off-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Hoist the code from xfs_bui_item_recover that igets an inode and marks
it as being part of log intent recovery. The next patch will want a
common function.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
When there are no ongoing transactions and the log contents have been
checkpointed back into the filesystem, the log performs 'covering',
which is to say that it log a dummy transaction to record the fact that
the tail has caught up with the head. This is a good time to clear log
incompat feature flags, because they are flags that are temporarily set
to limit the range of kernels that can replay a dirty log.
Since it's possible that some other higher level thread is about to
start logging items protected by a log incompat flag, we create a rwsem
so that upper level threads can coordinate this with the log. It would
probably be more performant to use a percpu rwsem, but the ability to
/try/ taking the write lock during covering is critical, and percpu
rwsems do not provide that.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Christoph Hellwig