This is a late set of changes from Deepa Dinamani doing an automated
treewide conversion of the inode and iattr structures from 'timespec'
to 'timespec64', to push the conversion from the VFS layer into the
individual file systems.
There were no conflicts between this and the contents of linux-next
until just before the merge window, when we saw multiple problems:
- A minor conflict with my own y2038 fixes, which I could address
by adding another patch on top here.
- One semantic conflict with late changes to the NFS tree. I addressed
this by merging Deepa's original branch on top of the changes that
now got merged into mainline and making sure the merge commit includes
the necessary changes as produced by coccinelle.
- A trivial conflict against the removal of staging/lustre.
- Multiple conflicts against the VFS changes in the overlayfs tree.
These are still part of linux-next, but apparently this is no longer
intended for 4.18 [1], so I am ignoring that part.
As Deepa writes:
The series aims to switch vfs timestamps to use struct timespec64.
Currently vfs uses struct timespec, which is not y2038 safe.
The series involves the following:
1. Add vfs helper functions for supporting struct timepec64 timestamps.
2. Cast prints of vfs timestamps to avoid warnings after the switch.
3. Simplify code using vfs timestamps so that the actual
replacement becomes easy.
4. Convert vfs timestamps to use struct timespec64 using a script.
This is a flag day patch.
Next steps:
1. Convert APIs that can handle timespec64, instead of converting
timestamps at the boundaries.
2. Update internal data structures to avoid timestamp conversions.
Thomas Gleixner adds:
I think there is no point to drag that out for the next merge window.
The whole thing needs to be done in one go for the core changes which
means that you're going to play that catchup game forever. Let's get
over with it towards the end of the merge window.
[1] https://www.spinics.net/lists/linux-fsdevel/msg128294.html
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Merge tag 'vfs-timespec64' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground
Pull inode timestamps conversion to timespec64 from Arnd Bergmann:
"This is a late set of changes from Deepa Dinamani doing an automated
treewide conversion of the inode and iattr structures from 'timespec'
to 'timespec64', to push the conversion from the VFS layer into the
individual file systems.
As Deepa writes:
'The series aims to switch vfs timestamps to use struct timespec64.
Currently vfs uses struct timespec, which is not y2038 safe.
The series involves the following:
1. Add vfs helper functions for supporting struct timepec64
timestamps.
2. Cast prints of vfs timestamps to avoid warnings after the switch.
3. Simplify code using vfs timestamps so that the actual replacement
becomes easy.
4. Convert vfs timestamps to use struct timespec64 using a script.
This is a flag day patch.
Next steps:
1. Convert APIs that can handle timespec64, instead of converting
timestamps at the boundaries.
2. Update internal data structures to avoid timestamp conversions'
Thomas Gleixner adds:
'I think there is no point to drag that out for the next merge
window. The whole thing needs to be done in one go for the core
changes which means that you're going to play that catchup game
forever. Let's get over with it towards the end of the merge window'"
* tag 'vfs-timespec64' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground:
pstore: Remove bogus format string definition
vfs: change inode times to use struct timespec64
pstore: Convert internal records to timespec64
udf: Simplify calls to udf_disk_stamp_to_time
fs: nfs: get rid of memcpys for inode times
ceph: make inode time prints to be long long
lustre: Use long long type to print inode time
fs: add timespec64_truncate()
- Strengthen metadata checking to avoid ASSERTing on bad disk contents
- Validate btree records that are being retrieved for clients
- Strengthen root inode verification
- Convert license blurbs to SPDX tags
- Enable changing DAX flag on directories
- Fix some writeback deadlocks in reflink
- Refactor out some old xfs helpers
- Move type verifiers to a separate file
- Fix some fuzzer crashes
- Various other bug fixes
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Merge tag 'xfs-4.18-merge-10' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull more xfs updates from Darrick Wong:
"Here's the second round of patches for XFS for 4.18. Most of the
commits are small cleanups, bug fixes, and continued strengthening of
metadata verifiers; the bulk of the diff is the conversion of the
fs/xfs/ tree to use SPDX tags.
This series has been run through a full xfstests run over the weekend
and through a quick xfstests run against this morning's master, with
no major failures reported.
Summary:
- Strengthen metadata checking to avoid ASSERTing on bad disk
contents
- Validate btree records that are being retrieved for clients
- Strengthen root inode verification
- Convert license blurbs to SPDX tags
- Enable changing DAX flag on directories
- Fix some writeback deadlocks in reflink
- Refactor out some old xfs helpers
- Move type verifiers to a separate file
- Fix some fuzzer crashes
- Various other bug fixes"
* tag 'xfs-4.18-merge-10' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (31 commits)
xfs: update incore per-AG inode count
xfs: replace do_mod with native operations
xfs: don't call xfs_da_shrink_inode with NULL bp
xfs: clean up MIN/MAX
xfs: move various type verifiers to common file
xfs: xfs_reflink_convert_cow() memory allocation deadlock
xfs: setup VFS i_rwsem lockdep state correctly
xfs: fix string handling in label get/set functions
xfs: convert to SPDX license tags
xfs: validate btree records on retrieval
xfs: push corruption -> ESTALE conversion to xfs_nfs_get_inode()
xfs: verify root inode more thoroughly
xfs: verify COW extent size hint is valid in inode verifier
xfs: verify extent size hint is valid in inode verifier
xfs: catch bad stripe alignment configurations
iomap: fsync swap files before iterating mappings
xfs: use xfs_trans_getsb in xfs_sync_sb_buf
xfs: don't assert on corrupted unlinked inode list
xfs: explicitly pass buffer size to xfs_corruption_error
xfs: don't assert when on-disk btree pointers are garbage
...
For whatever reason we never actually update pagi_count (the in-core
perag inode count) when we allocate or free inode chunks. Online scrub
is going to use it, so we need to fix the accounting.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
* DAX broke a fundamental assumption of truncate of file mapped pages.
The truncate path assumed that it is safe to disconnect a pinned page
from a file and let the filesystem reclaim the physical block. With DAX
the page is equivalent to the filesystem block. Introduce
dax_layout_busy_page() to enable filesystems to wait for pinned DAX
pages to be released. Without this wait a filesystem could allocate
blocks under active device-DMA to a new file.
* DAX arranges for the block layer to be bypassed and uses
dax_direct_access() + copy_to_iter() to satisfy read(2) calls.
However, the memcpy_mcsafe() facility is available through the pmem
block driver. In order to safely handle media errors, via the DAX
block-layer bypass, introduce copy_to_iter_mcsafe().
* Fix cache management policy relative to the ACPI NFIT Platform
Capabilities Structure to properly elide cache flushes when they are not
necessary. The table indicates whether CPU caches are power-fail
protected. Clarify that a deep flush is always performed on
REQ_{FUA,PREFLUSH} requests.
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Merge tag 'libnvdimm-for-4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull libnvdimm updates from Dan Williams:
"This adds a user for the new 'bytes-remaining' updates to
memcpy_mcsafe() that you already received through Ingo via the
x86-dax- for-linus pull.
Not included here, but still targeting this cycle, is support for
handling memory media errors (poison) consumed via userspace dax
mappings.
Summary:
- DAX broke a fundamental assumption of truncate of file mapped
pages. The truncate path assumed that it is safe to disconnect a
pinned page from a file and let the filesystem reclaim the physical
block. With DAX the page is equivalent to the filesystem block.
Introduce dax_layout_busy_page() to enable filesystems to wait for
pinned DAX pages to be released. Without this wait a filesystem
could allocate blocks under active device-DMA to a new file.
- DAX arranges for the block layer to be bypassed and uses
dax_direct_access() + copy_to_iter() to satisfy read(2) calls.
However, the memcpy_mcsafe() facility is available through the pmem
block driver. In order to safely handle media errors, via the DAX
block-layer bypass, introduce copy_to_iter_mcsafe().
- Fix cache management policy relative to the ACPI NFIT Platform
Capabilities Structure to properly elide cache flushes when they
are not necessary. The table indicates whether CPU caches are
power-fail protected. Clarify that a deep flush is always performed
on REQ_{FUA,PREFLUSH} requests"
* tag 'libnvdimm-for-4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (21 commits)
dax: Use dax_write_cache* helpers
libnvdimm, pmem: Do not flush power-fail protected CPU caches
libnvdimm, pmem: Unconditionally deep flush on *sync
libnvdimm, pmem: Complete REQ_FLUSH => REQ_PREFLUSH
acpi, nfit: Remove ecc_unit_size
dax: dax_insert_mapping_entry always succeeds
libnvdimm, e820: Register all pmem resources
libnvdimm: Debug probe times
linvdimm, pmem: Preserve read-only setting for pmem devices
x86, nfit_test: Add unit test for memcpy_mcsafe()
pmem: Switch to copy_to_iter_mcsafe()
dax: Report bytes remaining in dax_iomap_actor()
dax: Introduce a ->copy_to_iter dax operation
uio, lib: Fix CONFIG_ARCH_HAS_UACCESS_MCSAFE compilation
xfs, dax: introduce xfs_break_dax_layouts()
xfs: prepare xfs_break_layouts() for another layout type
xfs: prepare xfs_break_layouts() to be called with XFS_MMAPLOCK_EXCL
mm, fs, dax: handle layout changes to pinned dax mappings
mm: fix __gup_device_huge vs unmap
mm: introduce MEMORY_DEVICE_FS_DAX and CONFIG_DEV_PAGEMAP_OPS
...
do_mod() is a hold-over from when we have different sizes for file
offsets and and other internal values for 40 bit XFS filesystems.
Hence depending on build flags variables passed to do_mod() could
change size. We no longer support those small format filesystems and
hence everything is of fixed size theses days, even on 32 bit
platforms.
As such, we can convert all the do_mod() callers to platform
optimised modulus operations as defined by linux/math64.h.
Individual conversions depend on the types of variables being used.
Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
xfs_attr3_leaf_create may have errored out before instantiating a buffer,
for example if the blkno is out of range. In that case there is no work
to do to remove it, and in fact xfs_da_shrink_inode will lead to an oops
if we try.
This also seems to fix a flaw where the original error from
xfs_attr3_leaf_create gets overwritten in the cleanup case, and it
removes a pointless assignment to bp which isn't used after this.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=199969
Reported-by: Xu, Wen <wen.xu@gatech.edu>
Tested-by: Xu, Wen <wen.xu@gatech.edu>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Get rid of the MIN/MAX macros and just use the native min/max macros
directly in the XFS code.
Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
New verification functions like xfs_verify_fsbno() and
xfs_verify_agino() are spread across multiple files and different
header files. They really don't fit cleanly into the places they've
been put, and have wider scope than the current header includes.
Move the type verifiers to a new file in libxfs (xfs-types.c) and
the prototypes to xfs_types.h where they will be visible to all the
code that uses the types.
Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
xfs_reflink_convert_cow() manipulates the incore extent list
in GFP_KERNEL context in the IO submission path whilst holding
locked pages under writeback. This is a memory reclaim deadlock
vector. This code is not in a transaction, so any memory allocations
it makes aren't protected via the memalloc_nofs_save() context that
transactions carry.
Hence we need to run this call under memalloc_nofs_save() context to
prevent potential memory allocations from being run as GFP_KERNEL
and deadlocking.
Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
When lockdep is enabled, it changes the type of the inode i_rwsem
semaphore before unlocking a newly instantiated inode. THere is the
possibility that there is already a waiter on that inode lock by the
time we unlock the new inode, so having lockdep re-initialise the
lock is a vector for trouble.
Avoid this whole situation by setting up the i_rwsem lockdep class
at the same time we set up the XFS inode i_ilock classes and so the
VFS doesn't have to change the lock class itself when it is
potentially unsafe.
This change is necessary because the equivalent fixes to the VFS code
made in commit 1e2e547a93 ("do d_instantiate/unlock_new_inode
combinations safely") are not relevant to XFS as it has it's own
internal inode cache lookup and instantiation routines.
Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
[sandeen: fix subject, avoid copy-out of uninit data in getlabel]
gcc-8 reports two warnings for the newly added getlabel/setlabel code:
fs/xfs/xfs_ioctl.c: In function 'xfs_ioc_getlabel':
fs/xfs/xfs_ioctl.c:1822:38: error: argument to 'sizeof' in 'strncpy' call is the same expression as the source; did you mean to use the size of the destination? [-Werror=sizeof-pointer-memaccess]
strncpy(label, sbp->sb_fname, sizeof(sbp->sb_fname));
^
In function 'strncpy',
inlined from 'xfs_ioc_setlabel' at /git/arm-soc/fs/xfs/xfs_ioctl.c:1863:2,
inlined from 'xfs_file_ioctl' at /git/arm-soc/fs/xfs/xfs_ioctl.c:1918:10:
include/linux/string.h:254:9: error: '__builtin_strncpy' output may be truncated copying 12 bytes from a string of length 12 [-Werror=stringop-truncation]
return __builtin_strncpy(p, q, size);
In both cases, part of the problem is that one of the strncpy()
arguments is a fixed-length character array with zero-padding rather
than a zero-terminated string. In the first one case, we also get an
odd warning about sizeof-pointer-memaccess, which doesn't seem right
(the sizeof is for an array that happens to be the same as the second
strncpy argument).
To work around the bogus warning, I use a plain 'XFSLABEL_MAX' for
the strncpy() length when copying the label in getlabel. For setlabel(),
using memcpy() with the correct length that is already known avoids
the second warning and is slightly simpler.
In a related issue, it appears that we accidentally skip the trailing
\0 when copying a 12-character label back to user space in getlabel().
Using the correct sizeof() argument here copies the extra character.
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85602
Fixes: f7664b3197 ("xfs: implement online get/set fs label")
Cc: Eric Sandeen <sandeen@redhat.com>
Cc: Martin Sebor <msebor@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/
This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:
for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done
And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:
$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}
/^ \* This program is free software/ {
hdr = 2.0;
next
}
/any later version./ {
tag = "GPL-2.0+"
next
}
/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}
/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}
/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}
// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}
END { }
$
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
So we don't check the validity of records as we walk the btree. When
there are corrupt records in the free space btree (e.g. zero
startblock/length or beyond EOAG) we just blindly use it and things
go bad from there. That leads to assert failures on debug kernels
like this:
XFS: Assertion failed: fs_is_ok, file: fs/xfs/libxfs/xfs_alloc.c, line: 450
....
Call Trace:
xfs_alloc_fixup_trees+0x368/0x5c0
xfs_alloc_ag_vextent_near+0x79a/0xe20
xfs_alloc_ag_vextent+0x1d3/0x330
xfs_alloc_vextent+0x5e9/0x870
Or crashes like this:
XFS (loop0): xfs_buf_find: daddr 0x7fb28 out of range, EOFS 0x8000
.....
BUG: unable to handle kernel NULL pointer dereference at 00000000000000c8
....
Call Trace:
xfs_bmap_add_extent_hole_real+0x67d/0x930
xfs_bmapi_write+0x934/0xc90
xfs_da_grow_inode_int+0x27e/0x2f0
xfs_dir2_grow_inode+0x55/0x130
xfs_dir2_sf_to_block+0x94/0x5d0
xfs_dir2_sf_addname+0xd0/0x590
xfs_dir_createname+0x168/0x1a0
xfs_rename+0x658/0x9b0
By checking that free space records pulled from the trees are
within the valid range, we catch many of these corruptions before
they can do damage.
This is a generic btree record checking deficiency. We need to
validate the records we fetch from all the different btrees before
we use them to catch corruptions like this.
This patch results in a corrupt record emitting an error message and
returning -EFSCORRUPTED, and the higher layers catch that and abort:
XFS (loop0): Size Freespace BTree record corruption in AG 0 detected!
XFS (loop0): start block 0x0 block count 0x0
XFS (loop0): Internal error xfs_trans_cancel at line 1012 of file fs/xfs/xfs_trans.c. Caller xfs_create+0x42a/0x670
.....
Call Trace:
dump_stack+0x85/0xcb
xfs_trans_cancel+0x19f/0x1c0
xfs_create+0x42a/0x670
xfs_generic_create+0x1f6/0x2c0
vfs_create+0xf9/0x180
do_mknodat+0x1f9/0x210
do_syscall_64+0x5a/0x180
entry_SYSCALL_64_after_hwframe+0x49/0xbe
.....
XFS (loop0): xfs_do_force_shutdown(0x8) called from line 1013 of file fs/xfs/xfs_trans.c. Return address = ffffffff81500868
XFS (loop0): Corruption of in-memory data detected. Shutting down filesystem
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
In xfs_imap_to_bp(), we convert a -EFSCORRUPTED error to -EINVAL if
we are doing an untrusted lookup. This is done because we need
failed filehandle lookups to report -ESTALE to the caller, and it
does this by converting -EINVAL and -ENOENT errors to -ESTALE.
The squashing of EFSCORRUPTED in imap_to_bp makes it impossible for
for xfs_iget(UNTRUSTED) callers to determine the difference between
"inode does not exist" and "corruption detected during lookup". We
realy need that distinction in places calling xfS_iget(UNTRUSTED),
so move the filehandle error case handling all the way out to
xfs_nfs_get_inode() where it is needed.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
When looking up the root inode at mount time, we don't actually do
any verification to check that the inode is allocated and accounted
for correctly in the INOBT. Make the checks on the root inode more
robust by making it an untrusted lookup. This forces the inode
lookup to use the inode btree to verify the inode is allocated
and mapped correctly to disk. This will also have the effect of
catching a significant number of AGI/INOBT related corruptions in
AG 0 at mount time.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
There are rules for vald extent size hints. We enforce them when
applications set them, but fuzzers violate those rules and that
screws us over. Validate COW extent size hint rules in the inode
verifier to catch this.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
There are rules for vald extent size hints. We enforce them when
applications set them, but fuzzers violate those rules and that
screws us over.
This results in alignment assertion failures when setting up
allocations such as this in direct IO:
XFS: Assertion failed: ap->length, file: fs/xfs/libxfs/xfs_bmap.c, line: 3432
....
Call Trace:
xfs_bmap_btalloc+0x415/0x910
xfs_bmapi_write+0x71c/0x12e0
xfs_iomap_write_direct+0x2a9/0x420
xfs_file_iomap_begin+0x4dc/0xa70
iomap_apply+0x43/0x100
iomap_file_buffered_write+0x62/0x90
xfs_file_buffered_aio_write+0xba/0x300
__vfs_write+0xd5/0x150
vfs_write+0xb6/0x180
ksys_write+0x45/0xa0
do_syscall_64+0x5a/0x180
entry_SYSCALL_64_after_hwframe+0x49/0xbe
And from xfs_db:
core.extsize = 10380288
Which is not an integer multiple of the block size, and so violates
Rule #7 for setting extent size hints. Validate extent size hint
rules in the inode verifier to catch this.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
- Strengthen inode number and structure validation when allocating inodes.
- Reduce pointless buffer allocations during cache miss
- Use FUA for pure data O_DSYNC directio writes
- Various iomap refactorings
- Strengthen quota metadata verification to avoid unfixable broken quota
- Make AGFL block freeing a deferred operation to avoid blowing out
transaction reservations when running complex operations
- Get rid of the log item descriptors to reduce log overhead
- Fix various reflink bugs where inodes were double-joined to
transactions
- Don't issue discards when trimming unwritten extents
- Refactor incore dquot initialization and retrieval interfaces
- Fix some locking problmes in the quota scrub code
- Strengthen btree structure checks in scrub code
- Rewrite swapfile activation to use iomap and support unwritten extents
- Make scrub exit to userspace sooner when corruptions or
cross-referencing problems are found
- Make scrub invoke the data fork scrubber directly on metadata inodes
- Don't do background reclamation of post-eof and cow blocks when the fs
is suspended
- Fix secondary superblock buffer lifespan hinting
- Refactor growfs to use table-dispatched functions instead of long
stringy functions
- Move growfs code to libxfs
- Implement online fs label getting and setting
- Introduce online filesystem repair (in a very limited capacity)
- Fix unit conversion problems in the realtime freemap iteration
functions
- Various refactorings and cleanups in preparation to remove buffer
heads in a future release
- Reimplement the old bmap call with iomap
- Remove direct buffer head accesses from seek hole/data
- Various bug fixes
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Merge tag 'xfs-4.18-merge-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull xfs updates from Darrick Wong:
"New features this cycle include the ability to relabel mounted
filesystems, support for fallocated swapfiles, and using FUA for pure
data O_DSYNC directio writes. With this cycle we begin to integrate
online filesystem repair and refactor the growfs code in preparation
for eventual subvolume support, though the road ahead for both
features is quite long.
There are also numerous refactorings of the iomap code to remove
unnecessary log overhead, to disentangle some of the quota code, and
to prepare for buffer head removal in a future upstream kernel.
Metadata validation continues to improve, both in the hot path
veifiers and the online filesystem check code. I anticipate sending a
second pull request in a few days with more metadata validation
improvements.
This series has been run through a full xfstests run over the weekend
and through a quick xfstests run against this morning's master, with
no major failures reported.
Summary:
- Strengthen inode number and structure validation when allocating
inodes.
- Reduce pointless buffer allocations during cache miss
- Use FUA for pure data O_DSYNC directio writes
- Various iomap refactorings
- Strengthen quota metadata verification to avoid unfixable broken
quota
- Make AGFL block freeing a deferred operation to avoid blowing out
transaction reservations when running complex operations
- Get rid of the log item descriptors to reduce log overhead
- Fix various reflink bugs where inodes were double-joined to
transactions
- Don't issue discards when trimming unwritten extents
- Refactor incore dquot initialization and retrieval interfaces
- Fix some locking problmes in the quota scrub code
- Strengthen btree structure checks in scrub code
- Rewrite swapfile activation to use iomap and support unwritten
extents
- Make scrub exit to userspace sooner when corruptions or
cross-referencing problems are found
- Make scrub invoke the data fork scrubber directly on metadata
inodes
- Don't do background reclamation of post-eof and cow blocks when the
fs is suspended
- Fix secondary superblock buffer lifespan hinting
- Refactor growfs to use table-dispatched functions instead of long
stringy functions
- Move growfs code to libxfs
- Implement online fs label getting and setting
- Introduce online filesystem repair (in a very limited capacity)
- Fix unit conversion problems in the realtime freemap iteration
functions
- Various refactorings and cleanups in preparation to remove buffer
heads in a future release
- Reimplement the old bmap call with iomap
- Remove direct buffer head accesses from seek hole/data
- Various bug fixes"
* tag 'xfs-4.18-merge-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (121 commits)
fs: use ->is_partially_uptodate in page_cache_seek_hole_data
fs: remove the buffer_unwritten check in page_seek_hole_data
fs: move page_cache_seek_hole_data to iomap.c
xfs: use iomap_bmap
iomap: add an iomap-based bmap implementation
iomap: add a iomap_sector helper
iomap: use __bio_add_page in iomap_dio_zero
iomap: move IOMAP_F_BOUNDARY to gfs2
iomap: fix the comment describing IOMAP_NOWAIT
iomap: inline data should be an iomap type, not a flag
mm: split ->readpages calls to avoid non-contiguous pages lists
mm: return an unsigned int from __do_page_cache_readahead
mm: give the 'ret' variable a better name __do_page_cache_readahead
block: add a lower-level bio_add_page interface
xfs: fix error handling in xfs_refcount_insert()
xfs: fix xfs_rtalloc_rec units
xfs: strengthen rtalloc query range checks
xfs: xfs_rtbuf_get should check the bmapi_read results
xfs: xfs_rtword_t should be unsigned, not signed
dax: change bdev_dax_supported() to support boolean returns
...
Use xfs_trans_getsb rather than reaching right in for
mp->m_sb_bp; I think this is more correct, and it facilitates
building this libxfs code in userspace as well.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Use the per-ag inode number verifiers to detect corrupt lists and error
out, instead of using ASSERTs.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Explicitly pass the buffer length to xfs_corruption_error() instead of
assuming XFS_CORRUPTION_DUMP_LEN so that we avoid dumping off the end
of the buffer.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Don't ASSERT when we encounter bad on-disk btree pointers in the debug
check functions. Log the error to leave breadcrumbs and let the upper
layers deal with it.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Instead of ASSERTing on null btree pointers in xfs_btree_ptr_to_daddr,
use the new block number verifiers to ensure that the btree pointer
doesn't point to any sensitive areas (AG headers, past-EOFS) and return
-EFSCORRUPTED if this is the case. Remove the ASSERT because on-disk
corruptions shouldn't trigger ASSERTs.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Make xfs_btree_check_ptr a non-debug function and introduce a new _debug
version that only runs when #ifdef DEBUG. This will enable us to reuse
the checking logic with other parts of the btree code.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Create a variant of xfs_dir2_data_freefind that is suitable for use in a
verifier. Because _freefind is called by the verifier, we simply
duplicate the _freefind function, convert the ASSERTs to return
__this_address, and modify the verifier to call our new function. Once
we've made it impossible for directory blocks with bad bestfree data to
make it into the filesystem we can remove the DEBUG code from the
regular _freefind function.
Underlying argument: corruption of on-disk metadata should return
-EFSCORRUPTED instead of blowing ASSERTs.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
If we're reading a node in a dir/attr btree and the buffer comes off the
disk with a magic number we don't recognize, don't ASSERT and don't set
a garbage buffer type (0 also triggers ASSERTs). Instead, report the
corruption, release the buffer, and return -EFSCORRUPTED because that's
what the dabtree is -- corrupt.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Don't ASSERT if the short form btree root pointer is zero. Now that we
use xfs_verify_agbno to check all short form btree pointers, we'll let
that log the error and pass it to the upper layers.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
If a btree lookup encounters an empty btree node or an empty btree leaf
on a multi-level btree, that's evidence of a corrupt on-disk btree.
Therefore, we should return -EFSCORRUPTED to the upper levels, not an
ASSERT failure.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Return -EFSCORRUPTED when the bnobt/cntbt return obviously corrupt
values, rather than letting them bounce around in the internal code.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
In xfs_dir2_leaf_addname we ASSERT if the length of the unused space
described by bestfree[0] is less the amount of space we wish to consume.
Immediately after it is a call to xfs_dir2_data_use_free where the
offset parameter is offset of the unused space and the length parameter
is the amount of space we wish to consume. Both values (and the unused
space pointer) are passed into xfs_dir2_data_check_free, which also
validates that the region of unused space is big enough to cover the
space we wish to consume. This is effectively the same check that the
ASSERT covers, and since a check failure results in a corruption message
being logged we can remove the ASSERT.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Don't bother ASSERTing when we're already going to log and return the
corruption status.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
On a directory, the DAX flag is merely a hint that files created in the
directory should have the DAX flag set at creation time. We don't care
if the underlying device supports DAX or not because directory metadata
are always cached in DRAM. We don't care if new files get the flag even
if the device doesn't support DAX because we always check for DAX
support before setting the VFS flag (S_DAX).
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Pull dcache lookup cleanups from Al Viro:
"Cleaning ->lookup() instances up - mostly d_splice_alias() conversions"
* 'work.lookup' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (29 commits)
switch the rest of procfs lookups to d_splice_alias()
procfs: switch instantiate_t to d_splice_alias()
don't bother with tid_fd_revalidate() in lookups
proc_lookupfd_common(): don't bother with instantiate unless the file is open
procfs: get rid of ancient BS in pid_revalidate() uses
cifs_lookup(): switch to d_splice_alias()
cifs_lookup(): cifs_get_inode_...() never returns 0 with *inode left NULL
9p: unify paths in v9fs_vfs_lookup()
ncp_lookup(): use d_splice_alias()
hfsplus: switch to d_splice_alias()
hfs: don't allow mounting over .../rsrc
hfs: use d_splice_alias()
omfs_lookup(): report IO errors, use d_splice_alias()
orangefs_lookup: simplify
openpromfs: switch to d_splice_alias()
xfs_vn_lookup: simplify a bit
adfs_lookup: do not fail with ENOENT on negatives, use d_splice_alias()
adfs_lookup_byname: .. *is* taken care of in fs/namei.c
romfs_lookup: switch to d_splice_alias()
qnx6_lookup: switch to d_splice_alias()
...
The heads of tha AGI unlinked list are only scanned on debug
kernels when the verifier runs. Change that to always scan the heads
and validate that the inode numbers are valid.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Switch to the iomap based bmap implementation to get rid of one of the
last users of xfs_get_blocks.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
generic/475 fired an assert failure just after the filesystem was
shut down:
XFS: Assertion failed: fs_is_ok, file: fs/xfs/libxfs/xfs_refcount.c, line: 182
.....
Call Trace:
xfs_refcount_insert+0x151/0x190
xfs_refcount_adjust_extents.constprop.11+0x9c/0x470
xfs_refcount_adjust.constprop.10+0xb0/0x270
xfs_refcount_finish_one+0x25a/0x420
xfs_trans_log_finish_refcount_update+0x2a/0x40
xfs_refcount_update_finish_item+0x35/0xa0
xfs_defer_finish+0x15e/0x4d0
xfs_reflink_remap_extent+0x1bc/0x610
xfs_reflink_remap_blocks+0x6e/0x280
xfs_reflink_remap_range+0x311/0x530
vfs_clone_file_range+0x119/0x200
....
If xfs_btree_insert() returns an error, the corruption check fires
instead of passing the error back the caller. The corruption check
should be after we've checked for an error, not before, thereby
avoiding assert failures if the filesystem shuts down during a
refcount btree record insert.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
All the realtime allocation functions deal with space on the rtdev in
units of realtime extents. However, struct xfs_rtalloc_rec confusingly
uses the word 'block' in the name, even though they're really extents.
Fix the naming problem and fix all the unit handling problems in the two
existing users.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Bill O'Donnell <billodo@redhat.com>
Strengthen the rtalloc range query checks to make sure that the keys do
not run off the end of the realtime device inappropriately. Note that
the query range functions require units of rt extents, not blocks,
despite the type name.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Bill O'Donnell <billodo@redhat.com>
The xfs_rtbuf_get function should check the block mapping it gets back
from bmapi_read. If there are no mappings or the mapping isn't a real
extent, we should return -EFSCORRUPTED rather than trying to read a
garbage value. We also require realtime bitmap blocks to be real,
written allocations.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Bill O'Donnell <billodo@redhat.com>
xfs_rtword_t is used for bit manipulations in the realtime bitmap file.
Since we're performing bit shifts with this type, we don't want sign
extension and we don't want to be left shifting negative quantities
because that's undefined behavior.
This also shuts up these UBSAN warnings:
UBSAN: Undefined behaviour in fs/xfs/libxfs/xfs_rtbitmap.c:833:48
signed integer overflow:
-2147483648 - 1 cannot be represented in type 'int'
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Bill O'Donnell <billodo@redhat.com>
The function return values are confusing with the way the function is
named. We expect a true or false return value but it actually returns
0/-errno. This makes the code very confusing. Changing the return values
to return a bool where if DAX is supported then return true and no DAX
support returns false.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Change bdev_dax_supported so it takes a bdev parameter. This enables
multi-device filesystems like xfs to check that a dax device can work for
the particular filesystem. Once that's in place, actually fix all the
parts of XFS where we need to be able to distinguish between datadev and
rtdev.
This patch fixes the problem where we screw up the dax support checking
in xfs if the datadev and rtdev have different dax capabilities.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
[rez: Re-added __bdev_dax_supported() for !CONFIG_FS_DAX cases]
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Convert XFS to embedded bio sets.
Acked-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
If one of the backup superblocks is found to differ seriously from
superblock 0, write out a fresh copy from the in-core sb.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Add a helper routine to attach quota information to inodes that are
about to undergo repair. If that fails, we need to schedule a
quotacheck for the next mount but allow the corrupted metadata repair to
continue.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Add a helper function to help us recover btree roots from the rmap data.
Callers pass in a list of rmap owner codes, buffer ops, and magic
numbers. We iterate the rmap records looking for owner matches, and
then read the matching blocks to see if the magic number & uuid match.
If so, we then read-verify the block, and if that passes then we retain
a pointer to the block with the highest level, assuming that by the end
of the call we will have found the root. This will be used to reset the
AGF/AGI btree root fields during their rebuild procedures.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
