xfs: timestamp updates cause excessive fdatasync log traffic
Sage Weil reported that a ceph test workload was writing to the
log on every fdatasync during an overwrite workload. Event tracing
showed that the only metadata modification being made was the
timestamp updates during the write(2) syscall, but fdatasync(2)
is supposed to ignore them. The key observation was that the
transactions in the log all looked like this:
INODE: #regs: 4 ino: 0x8b flags: 0x45 dsize: 32
And contained a flags field of 0x45 or 0x85, and had data and
attribute forks following the inode core. This means that the
timestamp updates were triggering dirty relogging of previously
logged parts of the inode that hadn't yet been flushed back to
disk.
There are two parts to this problem. The first is that XFS relogs
dirty regions in subsequent transactions, so it carries around the
fields that have been dirtied since the last time the inode was
written back to disk, not since the last time the inode was forced
into the log.
The second part is that on v5 filesystems, the inode change count
update during inode dirtying also sets the XFS_ILOG_CORE flag, so
on v5 filesystems this makes a timestamp update dirty the entire
inode.
As a result when fdatasync is run, it looks at the dirty fields in
the inode, and sees more than just the timestamp flag, even though
the only metadata change since the last fdatasync was just the
timestamps. Hence we force the log on every subsequent fdatasync
even though it is not needed.
To fix this, add a new field to the inode log item that tracks
changes since the last time fsync/fdatasync forced the log to flush
the changes to the journal. This flag is updated when we dirty the
inode, but we do it before updating the change count so it does not
carry the "core dirty" flag from timestamp updates. The fields are
zeroed when the inode is marked clean (due to writeback/freeing) or
when an fsync/datasync forces the log. Hence if we only dirty the
timestamps on the inode between fsync/fdatasync calls, the fdatasync
will not trigger another log force.
Over 100 runs of the test program:
Ext4 baseline:
runtime: 1.63s +/- 0.24s
avg lat: 1.59ms +/- 0.24ms
iops: ~2000
XFS, vanilla kernel:
runtime: 2.45s +/- 0.18s
avg lat: 2.39ms +/- 0.18ms
log forces: ~400/s
iops: ~1000
XFS, patched kernel:
runtime: 1.49s +/- 0.26s
avg lat: 1.46ms +/- 0.25ms
log forces: ~30/s
iops: ~1500
Reported-by: Sage Weil <sage@redhat.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Don't leak the UUID table when the module is unloaded.
(Found with kmemleak.)
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Setting or removing the "SGI_ACL_[FILE|DEFAULT]" attributes via the
XFS_IOC_ATTRMULTI_BY_HANDLE ioctl completely bypasses the POSIX ACL
infrastructure, like setting the "trusted.SGI_ACL_[FILE|DEFAULT]" xattrs
did until commit 6caa1056. Similar to that commit, invalidate cached
acls when setting/removing them via the ioctl as well.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
When setting attributes via XFS_IOC_ATTRMULTI_BY_HANDLE, the user-space
buffer is copied into a new kernel-space buffer via memdup_user; that
buffer then isn't freed.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
In xfs_acl_from_disk, instead of trusting that xfs_acl.acl_cnt is correct,
make sure that the length of the attributes is correct as well. Also, turn
the aclp parameter into a const pointer.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
ACLs are stored as extended attributes of the inode to which they apply.
XFS converts the standard "system.posix_acl_[access|default]" attribute
names used to control ACLs to "trusted.SGI_ACL_[FILE|DEFAULT]" as stored
on-disk. These xattrs are directly exposed in on-disk format via
getxattr/setxattr, without any ACL aware code in the path to perform
validation, etc. This is partly historical and supports backup/restore
applications such as xfsdump to back up and restore the binary blob that
represents ACLs as-is.
Andreas reports that the ACLs observed via the getfacl interface is not
consistent when ACLs are set directly via the setxattr path. This occurs
because the ACLs are cached in-core against the inode and the xattr path
has no knowledge that the operation relates to ACLs.
Update the xattr set codepath to trap writes of the special XFS ACL
attributes and invalidate the associated cached ACL when this occurs.
This ensures that the correct ACLs are used on a subsequent operation
through the actual ACL interface.
Note that this does not update or add support for setting the ACL xattrs
directly beyond the restore use case that requires a correctly formatted
binary blob and to restore a consistent i_mode at the same time. It is
still possible for a root user to set an invalid or inconsistent (with
i_mode) ACL blob on-disk and potentially cause corruption.
[ With fixes from Andreas Gruenbacher. ]
Reported-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The code initially committed didn't have the same checks for write
faults as the dax_pmd_fault code and hence treats all faults as
write faults. We can get read faults through this path because they
is no pmd_mkwrite path for write faults similar to the normal page
fault path. Hence we need to ensure that we only do c/mtime updates
on write faults, and freeze protection is unnecessary for read
faults.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
->pfn_mkwrite support is needed so that when a page with allocated
backing store takes a write fault we can check that the fault has
not raced with a truncate and is pointing to a region beyond the
current end of file.
This also allows us to update the timestamp on the inode, too, which
fixes a generic/080 failure.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
For DAX, we are now doing block zeroing during allocation. This
means we no longer need a special DAX fault IO completion callback
to do unwritten extent conversion. Because mmap never extends the
file size (it SEGVs the process) we don't need a callback to update
the file size, either. Hence we can remove the completion callbacks
from the __dax_fault and __dax_mkwrite calls.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
DAX has a page fault serialisation problem with block allocation.
Because it allows concurrent page faults and does not have a page
lock to serialise faults to the same page, it can get two concurrent
faults to the page that race.
When two read faults race, this isn't a huge problem as the data
underlying the page is not changing and so "detect and drop" works
just fine. The issues are to do with write faults.
When two write faults occur, we serialise block allocation in
get_blocks() so only one faul will allocate the extent. It will,
however, be marked as an unwritten extent, and that is where the
problem lies - the DAX fault code cannot differentiate between a
block that was just allocated and a block that was preallocated and
needs zeroing. The result is that both write faults end up zeroing
the block and attempting to convert it back to written.
The problem is that the first fault can zero and convert before the
second fault starts zeroing, resulting in the zeroing for the second
fault overwriting the data that the first fault wrote with zeros.
The second fault then attempts to convert the unwritten extent,
which is then a no-op because it's already written. Data loss occurs
as a result of this race.
Because there is no sane locking construct in the page fault code
that we can use for serialisation across the page faults, we need to
ensure block allocation and zeroing occurs atomically in the
filesystem. This means we can still take concurrent page faults and
the only time they will serialise is in the filesystem
mapping/allocation callback. The page fault code will always see
written, initialised extents, so we will be able to remove the
unwritten extent handling from the DAX code when all filesystems are
converted.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
To enable DAX to do atomic allocation of zeroed extents, we need to
drive the block zeroing deep into the allocator. Because
xfs_bmapi_write() can return merged extents on allocation that were
only partially allocated (i.e. requested range spans allocated and
hole regions, allocation into the hole was contiguous), we cannot
zero the extent returned from xfs_bmapi_write() as that can
overwrite existing data with zeros.
Hence we have to drive the extent zeroing into the allocation code,
prior to where we merge the extents into the BMBT and return the
resultant map. This means we need to propagate this need down to
the xfs_alloc_vextent() and issue the block zeroing at this point.
While this functionality is being introduced for DAX, there is no
reason why it is specific to DAX - we can per-zero blocks during the
allocation transaction on any type of device. It's just slow (and
usually slower than unwritten allocation and conversion) on
traditional block devices so doesn't tend to get used. We can,
however, hook hardware zeroing optimisations via sb_issue_zeroout()
to this operation, so it may be useful in future and hence the
"allocate zeroed blocks" API needs to be implementation neutral.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Both direct IO and DAX pass an offset and count into get_blocks that
will overflow a s64 variable when an IO goes into the last supported
block in a file (i.e. at offset 2^63 - 1FSB bytes). This can be seen
from the tracing:
xfs_get_blocks_alloc: [...] offset 0x7ffffffffffff000 count 4096
xfs_gbmap_direct: [...] offset 0x7ffffffffffff000 count 4096
xfs_gbmap_direct_none:[...] offset 0x7ffffffffffff000 count 4096
0x7ffffffffffff000 + 4096 = 0x8000000000000000, and hence that
overflows the s64 offset and we fail to detect the need for a
filesize update and an ioend is not allocated.
This is *mostly* avoided for direct IO because such extending IOs
occur with full block allocation, and so the "IS_UNWRITTEN()" check
still evaluates as true and we get an ioend that way. However, doing
single sector extending IOs to this last block will expose the fact
that file size updates will not occur after the first allocating
direct IO as the overflow will then be exposed.
There is one further complexity: the DAX page fault path also
exposes the same issue in block allocation. However, page faults
cannot extend the file size, so in this case we want to allocate the
block but do not want to allocate an ioend to enable file size
update at IO completion. Hence we now need to distinguish between
the direct IO patch allocation and dax fault path allocation to
avoid leaking ioend structures.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Since xfsaild has been converted to kthread in 0030807c, it calls
try_to_freeze() during every AIL push iteration. It however doesn't set
itself as freezable, and therefore this try_to_freeze() will never do
anything.
Before (hopefully eventually) kthread freezing gets converted to fileystem
freezing, we'd rather mark xfsaild freezable (as it can generate I/O
during suspend).
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
If alloc_percpu() fails, we accidentally return PTR_ERR(NULL), which
means success, but we intended to return -ENOMEM.
Fixes: 225e463558 ('xfs: per-filesystem stats in sysfs')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Bill O'Donnell <billodo@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
So we need to fix the makefile to understand this, otherwise build
errors with CONFIG_PROC_FS=n occur.
Reported-and-tested-by: Jim Davis <jim.epost@gmail.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
remove_proc_subtree() was added in 3.9, and can be
used to simplify our procfile creation error handling
and cleanup, removing the nested gotos. It simply
removes fs/xfs and everything created under it.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
This patch modifies the stats counting macros and the callers
to those macros to properly increment, decrement, and add-to
the xfs stats counts. The counts for global and per-fs stats
are correctly advanced, and cleared by writing a "1" to the
corresponding clear file.
global counts: /sys/fs/xfs/stats/stats
per-fs counts: /sys/fs/xfs/sda*/stats/stats
global clear: /sys/fs/xfs/stats/stats_clear
per-fs clear: /sys/fs/xfs/sda*/stats/stats_clear
[dchinner: cleaned up macro variables, removed CONFIG_FS_PROC around
stats structures and macros. ]
Signed-off-by: Bill O'Donnell <billodo@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
This patch implements per-filesystem stats objects in sysfs. It
depends on the application of the previous patch series that
develops the infrastructure to support both xfs global stats and
xfs per-fs stats in sysfs.
Stats objects are instantiated when an xfs filesystem is mounted
and deleted on unmount. With this patch, the stats directory is
created and populated with the familiar stats and stats_clear files.
Example:
/sys/fs/xfs/sda9/stats/stats
/sys/fs/xfs/sda9/stats/stats_clear
With this patch, the individual counts within the new per-fs
stats file(s) remain at zero. Functions that use the the macros
to increment, decrement, and add-to the per-fs stats counts will
be covered in a separate new patch to follow this one. Note that
the counts within the global stats file (/sys/fs/xfs/stats/stats)
advance normally and can be cleared as it was prior to this patch.
[dchinner: move setup/teardown to xfs_fs_{fill|put}_super() so
it is down before/after any path that uses the per-mount stats. ]
Signed-off-by: Bill O'Donnell <billodo@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
In an effort to get more useful out of "possible memory
allocation deadlock" messages, print the size of the
requested allocation, and dump the stack if the xfs error
level is tuned high.
The stack dump is implemented in define_xfs_printk_level()
for error levels >= LOGLEVEL_ERR, partly because it
seems generically useful, and also because kmem.c has
no knowledge of xfs error level tunables or other such bits,
it's very kmem-specific.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The gcc undefined behavior sanitizer caught this; surely
any sane memcpy implementation will no-op if size == 0,
but behavior with a *src of NULL is technically undefined
(declared nonnull), so avoid it here.
We are actually in this situation frequently via
xlog_commit_record(), because:
struct xfs_log_iovec reg = {
.i_addr = NULL,
.i_len = 0,
.i_type = XLOG_REG_TYPE_COMMIT,
};
Reported-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The total field from struct xfs_alloc_arg is a bit of an unknown
commodity. It is documented as the total block requirement for the
transaction and is used in this manner from most call sites by virtue of
passing the total block reservation of the transaction associated with
an allocation. Several xfs_bmapi_write() callers pass hardcoded values
of 0 or 1 for the total block requirement, which is a historical oddity
without any clear reasoning.
The xfs_iomap_write_direct() caller, for example, passes 0 for the total
block requirement. This has been determined to cause problems in the
form of ABBA deadlocks of AGF buffers due to incorrect AG selection in
the block allocator. Specifically, the xfs_alloc_space_available()
function incorrectly selects an AG that doesn't actually have sufficient
space for the allocation. This occurs because the args.total field is 0
and thus the remaining free space check on the AG doesn't actually
consider the size of the allocation request. This locks the AGF buffer,
the allocation attempt proceeds and ultimately fails (in
xfs_alloc_fix_minleft()), and xfs_alloc_vexent() moves on to the next
AG. In turn, this can lead to incorrect AG locking order (if the
allocator wraps around, attempting to lock AG 0 after acquiring AG N)
and thus deadlock if racing with another operation. This problem has
been reproduced via generic/299 on smallish (1GB) ramdisk test devices.
To avoid this problem, replace the undocumented hardcoded total
parameters from the iomap and utility callers to pass the block
reservation used for the associated transaction. This is consistent with
other xfs_bmapi_write() callers throughout XFS. The assumption is that
the total field allows the selection of an AG that can handle the entire
operation rather than simply the allocation/range being requested (e.g.,
resulting btree splits, etc.). This addresses the aforementioned
generic/299 hang by ensuring AG selection only occurs when the
allocation can be satisfied by the AG.
Reported-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Currently, we depends on Linux XATTR value for on disk
definition. Which causes trouble on other platforms and
maybe also if this value was to change.
Fix it by creating a custom definition independent from
those in Linux (although with the same values), so it is OK
with the be16 fields used for holding these attributes.
This patch reflects a change in xfsprogs.
Signed-off-by: Jan Tulak <jtulak@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Remove a hard dependency of Linux XATTR_LIST_MAX value by using
a prefixed version. This patch reflects the same change in xfsprogs.
Signed-off-by: Jan Tulak <jtulak@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Just fix two typos in code comments.
Signed-off-by: Geliang Tang <geliangtang@163.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Add a tracepoint in xfs_zero_eof() to facilitate tracking and debugging
EOF zeroing events. This has proven useful in the context of other
direct I/O tracepoints to ensure EOF zeroing occurs within appropriate
file ranges.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
XFS supports and typically allows concurrent asynchronous direct I/O
submission to a single file. One exception to the rule is that file
extending dio writes that start beyond the current EOF (e.g.,
potentially create a hole at EOF) require exclusive I/O access to the
file. This is because such writes must zero any pre-existing blocks
beyond EOF that are exposed by virtue of now residing within EOF as a
result of the write about to be submitted.
Before EOF zeroing can occur, the current file i_size must be stabilized
to avoid data corruption. In this scenario, XFS upgrades the iolock to
exclude any further I/O submission, waits on in-flight I/O to complete
to ensure i_size is up to date (i_size is updated on dio write
completion) and restarts the various checks against the state of the
file. The problem is that this protection sequence is triggered only
when the iolock is currently held shared. While this is true for async
dio in most cases, the caller may upgrade the lock in advance based on
arbitrary circumstances with respect to EOF zeroing. For example, the
iolock is always acquired exclusively if the start offset is not block
aligned. This means that even though the iolock is already held
exclusive for such I/Os, pending I/O is not drained and thus EOF zeroing
can occur based on an unstable i_size.
This problem has been reproduced as guest data corruption in virtual
machines with file-backed qcow2 virtual disks hosted on an XFS
filesystem. The virtual disks must be configured with aio=native mode
and the must not be truncated out to the maximum file size (as some virt
managers will do).
Update xfs_file_aio_write_checks() to unconditionally drain in-flight
dio before EOF zeroing can occur. Rather than trigger the wait based on
iolock state, use a new flag and upgrade the iolock when necessary. Note
that this results in a full restart of the inode checks even when the
iolock was already held exclusive when technically it is only required
to recheck i_size. This should be a rare enough occurrence that it is
preferable to keep the code simple rather than create an alternate
restart jump target.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Since the onset of v5 superblocks, the LSN of the last modification has
been included in a variety of on-disk data structures. This LSN is used
to provide log recovery ordering guarantees (e.g., to ensure an older
log recovery item is not replayed over a newer target data structure).
While this works correctly from the point a filesystem is formatted and
mounted, userspace tools have some problematic behaviors that defeat
this mechanism. For example, xfs_repair historically zeroes out the log
unconditionally (regardless of whether corruption is detected). If this
occurs, the LSN of the filesystem is reset and the log is now in a
problematic state with respect to on-disk metadata structures that might
have a larger LSN. Until either the log catches up to the highest
previously used metadata LSN or each affected data structure is modified
and written out without incident (which resets the metadata LSN), log
recovery is susceptible to filesystem corruption.
This problem is ultimately addressed and repaired in the associated
userspace tools. The kernel is still responsible to detect the problem
and notify the user that something is wrong. Check the superblock LSN at
mount time and fail the mount if it is invalid. From that point on,
trigger verifier failure on any metadata I/O where an invalid LSN is
detected. This results in a filesystem shutdown and guarantees that we
do not log metadata changes with invalid LSNs on disk. Since this is a
known issue with a known recovery path, present a warning to instruct
the user how to recover.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
This patch adds comm name and pid to warning messages printed by
kmem_alloc(), kmem_zone_alloc() and xfs_buf_allocate_memory().
This will help telling which memory allocations (e.g. kernel worker
threads, OOM victim tasks, neither) are stalling because these functions
are passing __GFP_NOWARN which suppresses not only backtrace but comm name
and pid.
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
A local format symlink inode is converted to extent format when an
extended attribute is set on an inode as part of the attribute fork
creation. This means a block is allocated, the local symlink target name
is copied to the block and the block is logged. Currently,
xfs_bmap_local_to_extents() handles logging the remote block data based
on the size of the data fork prior to the conversion. This is not
correct on v5 superblock filesystems, which add an additional header to
remote symlink blocks that is nonexistent in local format inodes.
As a result, the full length of the remote symlink block content is not
logged. This can lead to corruption should a crash occur and log
recovery replay this transaction.
Since a callout is already used to initialize the new remote symlink
block, update the local-to-extents conversion mechanism to make the
callout also responsible for logging the block. It is already required
to set the log buffer type and format the block appropriately based on
the superblock version. This ensures the remote symlink is always logged
correctly. Note that xfs_bmap_local_to_extents() is only called for
symlinks so there are no other callouts that require modification.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The iomap codepath (via get_blocks()) acquires and release the inode
lock in the case of a direct write that requires block allocation. This
is because xfs_iomap_write_direct() allocates a transaction, which means
the ilock must be dropped and reacquired after the transaction is
allocated and reserved.
xfs_iomap_write_direct() invokes xfs_iomap_eof_align_last_fsb() before
the transaction is created and thus before the ilock is reacquired. This
can lead to calls to xfs_iread_extents() and reads of the in-core extent
list without any synchronization (via xfs_bmap_eof() and
xfs_bmap_last_extent()). xfs_iread_extents() assert fails if the ilock
is not held, but this is not currently seen in practice as the current
callers had already invoked xfs_bmapi_read().
What has been seen in practice are reports of crashes down in the
xfs_bmap_eof() codepath on direct writes due to seemingly bogus pointer
references from xfs_iext_get_ext(). While an explicit reproducer is not
currently available to confirm the cause of the problem, crash analysis
and code inspection from David Jeffrey had identified the insufficient
locking.
xfs_iomap_eof_align_last_fsb() is called from other contexts with the
inode lock already held, so we cannot acquire it therein.
__xfs_get_blocks() acquires and drops the ilock with variable flags to
cover the event that the extent list must be read in. The common case is
that __xfs_get_blocks() acquires the shared ilock. To provide locking
around the last extent alignment call without adding more lock cycles to
the dio path, update xfs_iomap_write_direct() to expect the shared ilock
held on entry and do the extent alignment under its protection. Demote
the lock, if necessary, from __xfs_get_blocks() and push the
xfs_qm_dqattach() call outside of the shared lock critical section.
Also, add an assert to document that the extent list is always expected
to be present in this path. Otherwise, we risk a call to
xfs_iread_extents() while under the shared ilock. This is safe as all
current callers have executed an xfs_bmapi_read() call under the current
iolock context.
Reported-by: David Jeffery <djeffery@redhat.com>
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
When I ran xfstest/073 case, the remount process was blocked to wait
transactions to be zero. I found there was a io error happened, and
the setfilesize transaction was not released properly. We should add
the changes to cancel the io error in this case.
Reproduction steps:
1. dd if=/dev/zero of=xfs1.img bs=1M count=2048
2. mkfs.xfs xfs1.img
3. losetup -f ./xfs1.img /dev/loop0
4. mount -t xfs /dev/loop0 /home/test_dir/
5. mkdir /home/test_dir/test
6. mkfs.xfs -dfile,name=image,size=2g
7. mount -t xfs -o loop image /home/test_dir/test
8. cp a file bigger than 2g to /home/test_dir/test
9. mount -t xfs -o remount,ro /home/test_dir/test
[ dchinner: moved io error detection to xfs_setfilesize_ioend() after
transaction context restoration. ]
Signed-off-by: Zhao Hongjiang <zhaohongjiang@huawei.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
This patch is the next step toward per-fs xfs stats. The patch makes
the show and clear routines able to handle any stats structure
associated with a kobject.
Instead of a single global xfsstats structure, add kobject and a pointer
to a per-cpu struct xfsstats. Modify the macros that manipulate the stats
accordingly: XFS_STATS_INC, XFS_STATS_DEC, and XFS_STATS_ADD now access
xfsstats->xs_stats.
The sysfs functions need to get from the kobject back to the xfsstats
structure which contains it, and pass the pointer to the ->xs_stats
percpu structure into the show & clear routines.
Signed-off-by: Bill O'Donnell <billodo@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
As a part of the series to move xfs global stats from procfs to sysfs,
this patch consolidates the sysfs ops functions and removes redundancy.
Signed-off-by: Bill O'Donnell <billodo@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
As a part of the work to move xfs global stats from procfs to sysfs,
this patch removes the now unused procfs code that was xfs stat specific.
Signed-off-by: Bill O'Donnell <billodo@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
As a part of the work to move xfs global stats from procfs to sysfs,
this patch creates the symlink from proc/fs/xfs/stat to sys/fs/xfs/stats.
Signed-off-by: Bill O'Donnell <billodo@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Currently, xfs global stats are in procfs. This patch introduces
(replicates) the global stats in sysfs. Additionally a stats_clear file
is introduced in sysfs.
Signed-off-by: Bill O'Donnell <billodo@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Use DAX to provide support for huge pages.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In order to handle the !CONFIG_TRANSPARENT_HUGEPAGES case, we need to
return VM_FAULT_FALLBACK from the inlined dax_pmd_fault(), which is
defined in linux/mm.h. Given that we don't want to include <linux/mm.h>
in <linux/fs.h>, the easiest solution is to move the DAX-related
functions to a new header, <linux/dax.h>. We could also have moved
VM_FAULT_* definitions to a new header, or a different header that isn't
quite such a boil-the-ocean header as <linux/mm.h>, but this felt like
the best option.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This update contains:
o large rework of EFI/EFD lifecycle handling to fix log recovery corruption
issues, crashes and unmount hangs
o separate metadata UUID on disk to enable changing boot label UUID for v5
filesystems
o fixes for gcc miscompilation on certain platforms and optimisation levels
o remote attribute allocation and recovery corruption fixes
o inode lockdep annotation rework to fix bugs with too many subclasses
o directory inode locking changes to prevent lockdep false positives
o a handful of minor corruption fixes
o various other small cleanups and bug fixes
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Merge tag 'xfs-for-linus-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs
Pull xfs updates from Dave Chinner:
"There isn't a whole lot to this update - it's mostly bug fixes and
they are spread pretty much all over XFS. There are some corruption
fixes, some fixes for log recovery, some fixes that prevent unount
from hanging, a lockdep annotation rework for inode locking to prevent
false positives and the usual random bunch of cleanups and minor
improvements.
Deatils:
- large rework of EFI/EFD lifecycle handling to fix log recovery
corruption issues, crashes and unmount hangs
- separate metadata UUID on disk to enable changing boot label UUID
for v5 filesystems
- fixes for gcc miscompilation on certain platforms and optimisation
levels
- remote attribute allocation and recovery corruption fixes
- inode lockdep annotation rework to fix bugs with too many
subclasses
- directory inode locking changes to prevent lockdep false positives
- a handful of minor corruption fixes
- various other small cleanups and bug fixes"
* tag 'xfs-for-linus-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs: (42 commits)
xfs: fix error gotos in xfs_setattr_nonsize
xfs: add mssing inode cache attempts counter increment
xfs: return errors from partial I/O failures to files
libxfs: bad magic number should set da block buffer error
xfs: fix non-debug build warnings
xfs: collapse allocsize and biosize mount option handling
xfs: Fix file type directory corruption for btree directories
xfs: lockdep annotations throw warnings on non-debug builds
xfs: Fix uninitialized return value in xfs_alloc_fix_freelist()
xfs: inode lockdep annotations broke non-lockdep build
xfs: flush entire file on dio read/write to cached file
xfs: Fix xfs_attr_leafblock definition
libxfs: readahead of dir3 data blocks should use the read verifier
xfs: stop holding ILOCK over filldir callbacks
xfs: clean up inode lockdep annotations
xfs: swap leaf buffer into path struct atomically during path shift
xfs: relocate sparse inode mount warning
xfs: dquots should be stamped with sb_meta_uuid
xfs: log recovery needs to validate against sb_meta_uuid
xfs: growfs not aware of sb_meta_uuid
...
Pull vfs updates from Al Viro:
"In this one:
- d_move fixes (Eric Biederman)
- UFS fixes (me; locking is mostly sane now, a bunch of bugs in error
handling ought to be fixed)
- switch of sb_writers to percpu rwsem (Oleg Nesterov)
- superblock scalability (Josef Bacik and Dave Chinner)
- swapon(2) race fix (Hugh Dickins)"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (65 commits)
vfs: Test for and handle paths that are unreachable from their mnt_root
dcache: Reduce the scope of i_lock in d_splice_alias
dcache: Handle escaped paths in prepend_path
mm: fix potential data race in SyS_swapon
inode: don't softlockup when evicting inodes
inode: rename i_wb_list to i_io_list
sync: serialise per-superblock sync operations
inode: convert inode_sb_list_lock to per-sb
inode: add hlist_fake to avoid the inode hash lock in evict
writeback: plug writeback at a high level
change sb_writers to use percpu_rw_semaphore
shift percpu_counter_destroy() into destroy_super_work()
percpu-rwsem: kill CONFIG_PERCPU_RWSEM
percpu-rwsem: introduce percpu_rwsem_release() and percpu_rwsem_acquire()
percpu-rwsem: introduce percpu_down_read_trylock()
document rwsem_release() in sb_wait_write()
fix the broken lockdep logic in __sb_start_write()
introduce __sb_writers_{acquired,release}() helpers
ufs_inode_get{frag,block}(): get rid of 'phys' argument
ufs_getfrag_block(): tidy up a bit
...
Many file systems that implement the show_options hook fail to correctly
escape their output which could lead to unescaped characters (e.g. new
lines) leaking into /proc/mounts and /proc/[pid]/mountinfo files. This
could lead to confusion, spoofed entries (resulting in things like
systemd issuing false d-bus "mount" notifications), and who knows what
else. This looks like it would only be the root user stepping on
themselves, but it's possible weird things could happen in containers or
in other situations with delegated mount privileges.
Here's an example using overlay with setuid fusermount trusting the
contents of /proc/mounts (via the /etc/mtab symlink). Imagine the use
of "sudo" is something more sneaky:
$ BASE="ovl"
$ MNT="$BASE/mnt"
$ LOW="$BASE/lower"
$ UP="$BASE/upper"
$ WORK="$BASE/work/ 0 0
none /proc fuse.pwn user_id=1000"
$ mkdir -p "$LOW" "$UP" "$WORK"
$ sudo mount -t overlay -o "lowerdir=$LOW,upperdir=$UP,workdir=$WORK" none /mnt
$ cat /proc/mounts
none /root/ovl/mnt overlay rw,relatime,lowerdir=ovl/lower,upperdir=ovl/upper,workdir=ovl/work/ 0 0
none /proc fuse.pwn user_id=1000 0 0
$ fusermount -u /proc
$ cat /proc/mounts
cat: /proc/mounts: No such file or directory
This fixes the problem by adding new seq_show_option and
seq_show_option_n helpers, and updating the vulnerable show_option
handlers to use them as needed. Some, like SELinux, need to be open
coded due to unusual existing escape mechanisms.
[akpm@linux-foundation.org: add lost chunk, per Kees]
[keescook@chromium.org: seq_show_option should be using const parameters]
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Acked-by: Jan Kara <jack@suse.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Cc: J. R. Okajima <hooanon05g@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull core block updates from Jens Axboe:
"This first core part of the block IO changes contains:
- Cleanup of the bio IO error signaling from Christoph. We used to
rely on the uptodate bit and passing around of an error, now we
store the error in the bio itself.
- Improvement of the above from myself, by shrinking the bio size
down again to fit in two cachelines on x86-64.
- Revert of the max_hw_sectors cap removal from a revision again,
from Jeff Moyer. This caused performance regressions in various
tests. Reinstate the limit, bump it to a more reasonable size
instead.
- Make /sys/block/<dev>/queue/discard_max_bytes writeable, by me.
Most devices have huge trim limits, which can cause nasty latencies
when deleting files. Enable the admin to configure the size down.
We will look into having a more sane default instead of UINT_MAX
sectors.
- Improvement of the SGP gaps logic from Keith Busch.
- Enable the block core to handle arbitrarily sized bios, which
enables a nice simplification of bio_add_page() (which is an IO hot
path). From Kent.
- Improvements to the partition io stats accounting, making it
faster. From Ming Lei.
- Also from Ming Lei, a basic fixup for overflow of the sysfs pending
file in blk-mq, as well as a fix for a blk-mq timeout race
condition.
- Ming Lin has been carrying Kents above mentioned patches forward
for a while, and testing them. Ming also did a few fixes around
that.
- Sasha Levin found and fixed a use-after-free problem introduced by
the bio->bi_error changes from Christoph.
- Small blk cgroup cleanup from Viresh Kumar"
* 'for-4.3/core' of git://git.kernel.dk/linux-block: (26 commits)
blk: Fix bio_io_vec index when checking bvec gaps
block: Replace SG_GAPS with new queue limits mask
block: bump BLK_DEF_MAX_SECTORS to 2560
Revert "block: remove artifical max_hw_sectors cap"
blk-mq: fix race between timeout and freeing request
blk-mq: fix buffer overflow when reading sysfs file of 'pending'
Documentation: update notes in biovecs about arbitrarily sized bios
block: remove bio_get_nr_vecs()
fs: use helper bio_add_page() instead of open coding on bi_io_vec
block: kill merge_bvec_fn() completely
md/raid5: get rid of bio_fits_rdev()
md/raid5: split bio for chunk_aligned_read
block: remove split code in blkdev_issue_{discard,write_same}
btrfs: remove bio splitting and merge_bvec_fn() calls
bcache: remove driver private bio splitting code
block: simplify bio_add_page()
block: make generic_make_request handle arbitrarily sized bios
blk-cgroup: Drop unlikely before IS_ERR(_OR_NULL)
block: don't access bio->bi_error after bio_put()
block: shrink struct bio down to 2 cache lines again
...
As the code stands today, if xfs_trans_reserve() fails, we
goto out_dqrele, which does not free the allocated transaction.
Fix up the goto targets to undo everything properly.
Addresses-Coverity-Id: 145571
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Increasing the inode cache attempt counter was apparently dropped while
refactoring the cache code and so stayed at the initial 0 value. Add the
increment back to make the runtime stats more useful.
Signed-off-by: Lucas Stach <dev@lynxeye.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
There is an issue with xfs's error reporting in some cases of I/O partially
failing and partially succeeding. Calls like fsync() can report success even
though not all I/O was successful in partial-failure cases such as one disk of
a RAID0 array being offline.
The issue can occur when there are more than one bio per xfs_ioend struct.
Each call to xfs_end_bio() for a bio completing will write a value to
ioend->io_error. If a successful bio completes after any failed bio, no
error is reported do to it writing 0 over the error code set by any failed bio.
The I/O error information is now lost and when the ioend is completed
only success is reported back up the filesystem stack.
xfs_end_bio() should only set ioend->io_error in the case of BIO_UPTODATE
being clear. ioend->io_error is initialized to 0 at allocation so only needs
to be updated by a failed bio. Also check that ioend->io_error is 0 so that
the first error reported will be the error code returned.
Cc: stable@vger.kernel.org
Signed-off-by: David Jeffery <djeffery@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
If xfs_da3_node_read_verify() doesn't recognize the magic number of a
buffer it's just read, set the buffer error to -EFSCORRUPTED so that
the error can be sent up to userspace. Without this patch we'll
notice the bad magic eventually while trying to traverse or change
the block, but we really ought to fail early in the verifier.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
There seem to be a couple of new set-but-unused build warnings
that gcc 4.9.3 is now warning about. These are not regressions, just
the compiler being more picky.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The allocsize and biosize mount options are handled identically,
other than allocsize accepting suffixes. suffix_kstrtoint handles
bare numbers just fine too, so these can be collapsed.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Users have occasionally reported that file type for some directory
entries is wrong. This mostly happened after updating libraries some
libraries. After some debugging the problem was traced down to
xfs_dir2_node_replace(). The function uses args->filetype as a file type
to store in the replaced directory entry however it also calls
xfs_da3_node_lookup_int() which will store file type of the current
directory entry in args->filetype. Thus we fail to change file type of a
directory entry to a proper type.
Fix the problem by storing new file type in a local variable before
calling xfs_da3_node_lookup_int().
cc: <stable@vger.kernel.org> # 3.16 - 4.x
Reported-by: Giacomo Comes <comes@naic.edu>
Signed-off-by: Jan Kara <jack@suse.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
SO, now if we enable lockdep without enabling CONFIG_XFS_DEBUG,
the lockdep annotations throw a warning because the assert that uses
the lockdep define is not built in:
fs/xfs/xfs_inode.c:367:1: warning: 'xfs_lockdep_subclass_ok' defined but not used [-Wunused-function]
xfs_lockdep_subclass_ok(
So now we need to create an ifdef mess to sort this all out, because
we need to handle all the combinations of CONFIG_XFS_DEBUG=[y|n],
CONFIG_XFS_WARNING=[y|n] and CONFIG_LOCKDEP=[y|n] appropriately.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
xfs_alloc_fix_freelist() can sometimes jump to out_agbp_relse
without ever setting value of 'error' variable which is then
returned. This can happen e.g. when pag->pagf_init is set but AG is
for metadata and we want to allocate user data.
Fix the problem by initializing 'error' to 0, which is the desired
return value when we decide to skip this group.
CC: xfs@oss.sgi.com
Coverity-id: 1309714
Signed-off-by: Jan Kara <jack@suse.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Fix CONFIG_LOCKDEP=n build, because asserts I put in to ensure we
aren't overrunning lockdep subclasses in commit 0952c81 ("xfs:
clean up inode lockdep annotations") use a define that doesn't
exist when CONFIG_LOCKDEP=n
Only check the subclass limits when lockdep is actually enabled.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Filesystems are responsible to manage file coherency between the page
cache and direct I/O. The generic dio code flushes dirty pages over the
range of a dio to ensure that the dio read or a future buffered read
returns the correct data. XFS has generally followed this pattern,
though traditionally has flushed and invalidated the range from the
start of the I/O all the way to the end of the file. This changed after
the following commit:
7d4ea3ce xfs: use ranged writeback and invalidation for direct IO
... as the full file flush was no longer necessary to deal with the
strange post-eof delalloc issues that were since fixed. Unfortunately,
we have since received complaints about performance degradation due to
the increased exclusive iolock cycles (which locks out parallel dio
submission) that occur when a file has cached pages. This does not occur
on filesystems that use the generic code as it also does not incorporate
locking.
The exclusive iolock is acquired any time the inode mapping has cached
pages, regardless of whether they reside in the range of the I/O or not.
If not, the flush/inval calls do no work and the lock was cycled for no
reason.
Under consideration of the cost of the exclusive iolock, update the dio
read and write handlers to flush and invalidate the entire mapping when
cached pages exist. In most cases, this increases the cost of the
initial flush sequence but eliminates the need for further lock cycles
and flushes so long as the workload does not actively mix direct and
buffered I/O. This also more closely matches historical behavior and
performance characteristics that users have come to expect.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
struct xfs_attr_leafblock contains 'entries' array which is declared
with size 1 altough it can in fact contain much more entries. Since this
array is followed by further struct members, gcc (at least in version
4.8.3) thinks that the array has the fixed size of 1 element and thus
may optimize away all accesses beyond the end of array resulting in
non-working code. This problem was only observed with userspace code in
xfsprogs, however it's better to be safe in kernel as well and have
matching kernel and xfsprogs definitions.
cc: <stable@vger.kernel.org>
Signed-off-by: Jan Kara <jack@suse.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
In the dir3 data block readahead function, use the regular read
verifier to check the block's CRC and spot-check the block contents
instead of directly calling only the spot-checking routine. This
prevents corrupted directory data blocks from being read into the
kernel, which can lead to garbage ls output and directory loops (if
say one of the entries contains slashes and other junk).
cc: <stable@vger.kernel.org> # 3.12 - 4.2
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The recent change to the readdir locking made in 40194ec ("xfs:
reinstate the ilock in xfs_readdir") for CXFS directory sanity was
probably the wrong thing to do. Deep in the readdir code we
can take page faults in the filldir callback, and so taking a page
fault while holding an inode ilock creates a new set of locking
issues that lockdep warns all over the place about.
The locking order for regular inodes w.r.t. page faults is io_lock
-> pagefault -> mmap_sem -> ilock. The directory readdir code now
triggers ilock -> page fault -> mmap_sem. While we cannot deadlock
at this point, it inverts all the locking patterns that lockdep
normally sees on XFS inodes, and so triggers lockdep. We worked
around this with commit 93a8614 ("xfs: fix directory inode iolock
lockdep false positive"), but that then just moved the lockdep
warning to deeper in the page fault path and triggered on security
inode locks. Fixing the shmem issue there just moved the lockdep
reports somewhere else, and now we are getting false positives from
filesystem freezing annotations getting confused.
Further, if we enter memory reclaim in a readdir path, we now get
lockdep warning about potential deadlocks because the ilock is held
when we enter reclaim. This, again, is different to a regular file
in that we never allow memory reclaim to run while holding the ilock
for regular files. Hence lockdep now throws
ilock->kmalloc->reclaim->ilock warnings.
Basically, the problem is that the ilock is being used to protect
the directory data and the inode metadata, whereas for a regular
file the iolock protects the data and the ilock protects the
metadata. From the VFS perspective, the i_mutex serialises all
accesses to the directory data, and so not holding the ilock for
readdir doesn't matter. The issue is that CXFS doesn't access
directory data via the VFS, so it has no "data serialisaton"
mechanism. Hence we need to hold the IOLOCK in the correct places to
provide this low level directory data access serialisation.
The ilock can then be used just when the extent list needs to be
read, just like we do for regular files. The directory modification
code can take the iolock exclusive when the ilock is also taken,
and this then ensures that readdir is correct excluded while
modifications are in progress.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Lockdep annotations are a maintenance nightmare. Locking has to be
modified to suit the limitations of the annotations, and we're
always having to fix the annotations because they are unable to
express the complexity of locking heirarchies correctly.
So, next up, we've got more issues with lockdep annotations for
inode locking w.r.t. XFS_LOCK_PARENT:
- lockdep classes are exclusive and can't be ORed together
to form new classes.
- IOLOCK needs multiple PARENT subclasses to express the
changes needed for the readdir locking rework needed to
stop the endless flow of lockdep false positives involving
readdir calling filldir under the ILOCK.
- there are only 8 unique lockdep subclasses available,
so we can't create a generic solution.
IOWs we need to treat the 3-bit space available to each lock type
differently:
- IOLOCK uses xfs_lock_two_inodes(), so needs:
- at least 2 IOLOCK subclasses
- at least 2 IOLOCK_PARENT subclasses
- MMAPLOCK uses xfs_lock_two_inodes(), so needs:
- at least 2 MMAPLOCK subclasses
- ILOCK uses xfs_lock_inodes with up to 5 inodes, so needs:
- at least 5 ILOCK subclasses
- one ILOCK_PARENT subclass
- one RTBITMAP subclass
- one RTSUM subclass
For the IOLOCK, split the space into two sets of subclasses.
For the MMAPLOCK, just use half the space for the one subclass to
match the non-parent lock classes of the IOLOCK.
For the ILOCK, use 0-4 as the ILOCK subclasses, 5-7 for the
remaining individual subclasses.
Because they are now all different, modify xfs_lock_inumorder() to
handle the nested subclasses, and to assert fail if passed an
invalid subclass. Further, annotate xfs_lock_inodes() to assert fail
if an invalid combination of lock primitives and inode counts are
passed that would result in a lockdep subclass annotation overflow.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The node directory lookup code uses a state structure that tracks the
path of buffers used to search for the hash of a filename through the
leaf blocks. When the lookup encounters a block that ends with the
requested hash, but the entry has not yet been found, it must shift over
to the next block and continue looking for the entry (i.e., duplicate
hashes could continue over into the next block). This shift mechanism
involves walking back up and down the state structure, replacing buffers
at the appropriate btree levels as necessary.
When a buffer is replaced, the old buffer is released and the new buffer
read into the active slot in the path structure. Because the buffer is
read directly into the path slot, a buffer read failure can result in
setting a NULL buffer pointer in an active slot. This throws off the
state cleanup code in xfs_dir2_node_lookup(), which expects to release a
buffer from each active slot. Instead, a BUG occurs due to a NULL
pointer dereference:
BUG: unable to handle kernel NULL pointer dereference at 00000000000001e8
IP: [<ffffffffa0585063>] xfs_trans_brelse+0x2a3/0x3c0 [xfs]
...
RIP: 0010:[<ffffffffa0585063>] [<ffffffffa0585063>] xfs_trans_brelse+0x2a3/0x3c0 [xfs]
...
Call Trace:
[<ffffffffa05250c6>] xfs_dir2_node_lookup+0xa6/0x2c0 [xfs]
[<ffffffffa0519f7c>] xfs_dir_lookup+0x1ac/0x1c0 [xfs]
[<ffffffffa055d0e1>] xfs_lookup+0x91/0x290 [xfs]
[<ffffffffa05580b3>] xfs_vn_lookup+0x73/0xb0 [xfs]
[<ffffffff8122de8d>] lookup_real+0x1d/0x50
[<ffffffff8123330e>] path_openat+0x91e/0x1490
[<ffffffff81235079>] do_filp_open+0x89/0x100
...
This has been reproduced via a parallel fsstress and filesystem shutdown
workload in a loop. The shutdown triggers the read error in the
aforementioned codepath and causes the BUG in xfs_dir2_node_lookup().
Update xfs_da3_path_shift() to update the active path slot atomically
with respect to the caller when a buffer is replaced. This ensures that
the caller always sees the old or new buffer in the slot and prevents
the NULL pointer dereference.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The sparse inodes feature is currently considered experimental. We warn
at mount time from xfs_mount_validate_sb(). This function is part of the
superblock verifier codepath, however, which means it could be invoked
repeatedly on superblock reads or writes. This is currently only
noticeable from userspace, where mkfs produces multiple warnings at
format time.
As mkfs warnings were not the intent of this change, relocate the mount
time warning to xfs_fs_fill_super(), which is only invoked once and only
in kernel space.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Once the sb_uuid is changed, the wrong uuid is stamped into new
dquots on disk. Found by inspection, verified by generic/219.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Now that sb_uuid can be changed by the user, we cannot use this to
validate the metadata blocks being recovered belong to this
filesystem. We must check against the sb_meta_uuid as that will
remain unchanged.
There is a complication in this code - the superblock itself. We can
not check the sb_meta_uuid unconditionally, as that may not be set
on disk. Hence we must verify the superblock sb_uuid matches between
the log record and the in-core superblock.
Found by inspection after the previous two problems were found.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Adding this simple change to xfstests:common/rc::_scratch_mkfs_xfs:
+ if [ $mkfs_status -eq 0 ]; then
+ xfs_admin -U generate $SCRATCH_DEV > /dev/null
+ fi
triggers all sorts of errors in xfstests. xfs/104 is an example,
where growfs fails with a UUID mismatch corruption detected by
xfs_agf_write_verify() when trying to write the first new AG
headers.
Fix this problem by making sure we copy the sb_meta_uuid into new
metadata written by growfs.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
After changing the UUID on a v5 filesystem, xfstests fails
immediately on a debug kernel with:
XFS: Assertion failed: uuid_equal(&ip->i_d.di_uuid, &mp->m_sb.sb_uuid), file: fs/xfs/xfs_inode.c, line: 799
This needs to check against the sb_meta_uuid, not the user visible
UUID that was changed.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
It's entirely possible for userspace to ask for an xattr which
does not exist.
Normally, there is no problem whatsoever when we ask for such
a thing, but when we look at an obfuscated metadump image
on a debug kernel with selinux, we trip over this ASSERT in
xfs_da3_path_shift():
*result = -ENOENT; /* we're out of our tree */
ASSERT(args->op_flags & XFS_DA_OP_OKNOENT);
It (more or less) only shows up in the above scenario, because
xfs_metadump obfuscates attr names, but chooses names which
keep the same hash value - and xfs_da3_node_lookup_int does:
if (((retval == -ENOENT) || (retval == -ENOATTR)) &&
(blk->hashval == args->hashval)) {
error = xfs_da3_path_shift(state, &state->path, 1, 1,
&retval);
IOWS, we only get down to the xfs_da3_path_shift() ASSERT
if we are looking for an xattr which doesn't exist, but we
find xattrs on disk which have the same hash, and so might be
a hash collision, so we try the path shift. When *that*
fails to find what we're looking for, we hit the assert about
XFS_DA_OP_OKNOENT.
Simply setting XFS_DA_OP_OKNOENT in xfs_attr_get solves this
rather corner-case problem with no ill side effects. It's
fine for an attr name lookup to fail.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
If a failure occurs after the bmap free list is populated and before
xfs_bmap_finish() completes successfully (which returns a partial
list on failure), the bmap free list must be cancelled. Otherwise,
the extent items on the list are never freed and a memory leak
occurs.
Several random error paths throughout the code suffer this problem.
Fix these up such that xfs_bmap_cancel() is always called on error.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Several areas of code duplicate a pattern where we take the AIL lock,
check whether an item is in the AIL and remove it if so. Create a new
helper for this pattern and use it where appropriate.
Signed-off-by: Brian Foster <bfoster@redhat.com>
The btree cursor cleanup function takes an error parameter that
affects how buffers are released from the cursor. All buffers are
released in the event of error. Several callers do not specify the
XFS_BTREE_ERROR flag in the event of error, however. This can cause
buffers to hang around locked or with an elevated hold count and
thus lead to umount hangs in the event of errors.
Fix up the xfs_btree_del_cursor() callers to pass XFS_BTREE_ERROR if
the cursor is being torn down due to error.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The root inode is read as part of the xfs_mountfs() sequence and the
reference is dropped in the event of failure after we grab the
inode. The reference drop doesn't necessarily free the inode,
however. It marks it for reclaim and potentially kicks off the
reclaim workqueue. The workqueue is destroyed further up the error
path, which means we are subject to crash if the workqueue job runs
after this point or a memory leak which is identified if the
xfs_inode_zone is destroyed (e.g., on module removal). Both of these
outcomes are reproducible via manual instrumentation of a mount
error after the root inode xfs_iget() call in xfs_mountfs().
Update the xfs_mountfs() error path to cancel any potential reclaim
work items and to run a synchronous inode reclaim if the root inode
is marked for reclaim. This ensures that no jobs remain on the queue
before it is destroyed and that the root inode is freed before the
reclaim mechanism is torn down.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The first 4 bytes of every basic block in the physical log is stamped
with the current lsn. To support this mechanism, the log record header
(first block of each new log record) contains space for the original
first byte of each log record block before it is replaced with the lsn.
The log record header has space for 32k worth of blocks. The version 2
log adds new extended record headers for each additional 32k worth of
blocks beyond what is supported by the record header.
The log record checksum incorporates the log record header, the extended
headers and the record payload. xlog_cksum() checksums the extended
headers based on log->l_iclog_heads, which specifies the number of
extended headers in a log record based on the log buffer size mount
option. The log buffer size is variable, however, and thus means the
checksum can be calculated differently based on how a filesystem is
mounted. This is problematic if a filesystem crashes and recovery occurs
on a subsequent mount using a different log buffer size. For example,
crash an active filesystem that is mounted with the default (32k)
logbsize, attempt remount/recovery using '-o logbsize=64k' and the mount
fails on or warns about log checksum failures.
To avoid this problem, update xlog_cksum() to calculate the checksum
based on the size of the log buffer according to the log record. The
size is already included in the h_size field of the log record header
and thus is available at log recovery time. Extended log record headers
are also only written when the log record is large enough to require
them. This makes checksum calculation of log records consistent with the
extended record header mechanism as well as how on-disk records are
checksummed with various log buffer size mount options.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Inode cluster buffers are invalidated and cancelled when inode chunks
are freed to notify log recovery that previous logged updates to the
metadata buffer should be skipped. This ensures that log recovery does
not overwrite buffers that might have already been reused.
On v4 filesystems, inode chunk allocation and inode updates are logged
via the cluster buffers and thus cancellation is easily detected via
buffer cancellation items. v5 filesystems use the new icreate
transaction, which uses logical logging and ordered buffers to log a
full inode chunk allocation at once. The resulting icreate item often
spans multiple inode cluster buffers.
Log recovery checks for cancelled buffers when processing icreate log
items, but it has a couple problems. First, it uses the full length of
the inode chunk rather than the cluster size. Second, it uses the length
in FSB units rather than BB units. Either of these problems prevent
icreate recovery from identifying cancelled buffers and thus inode
initialization proceeds unconditionally.
Update xlog_recover_do_icreate_pass2() to iterate the icreate range in
cluster sized increments and check each increment for cancellation.
Since icreate is currently only used for the minimum atomic inode chunk
allocation, we expect that either all or none of the buffers will be
cancelled. Cancel the icreate if at least one buffer is cancelled to
avoid making a bad situation worse by initializing a partial inode
chunk, but detect such anomalies and warn the user.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Various log items have recovery tracepoints to identify whether a
particular log item is recovered or cancelled. Add the equivalent
tracepoints for the icreate transaction.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Log recovery occurs in two phases at mount time. In the first phase,
EFIs and EFDs are processed and potentially cancelled out. EFIs without
EFD objects are inserted into the AIL for processing and recovery in the
second phase. xfs_mountfs() runs various other operations between the
phases and is thus subject to failure. If failure occurs after the first
phase but before the second, pending EFIs sit on the AIL, pin it and
cause the mount to hang.
Update the mount sequence to ensure that pending EFIs are cancelled in
the event of failure. Add a recovery cancellation mechanism to iterate
the AIL and cancel all EFI items when requested. Plumb cancellation
support through the log mount finish helper and update xfs_mountfs() to
invoke cancellation in the event of failure after recovery has started.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The EFI is initialized with a reference count of 2. One for the EFI to
ensure the item makes it to the AIL and one for the subsequently created
EFD to release the EFI once the EFD is committed. Log recovery uses the
EFI in a similar manner, but implements a hack to remove both references
in one call once the EFD is handled.
Update log recovery to use EFI reference counting in a manner consistent
with the log. When an EFI is encountered during recovery, an EFI item is
allocated and inserted to the AIL directly. Since the EFI reference is
typically dropped when the EFI is unpinned and this is analogous with
AIL insertion, drop the EFI reference at this point.
When a corresponding EFD is encountered in the log, this indicates that
the extents were freed, no processing is required and the EFI can be
dropped. Update xlog_recover_efd_pass2() to simply drop the EFD
reference at this point rather than open code the AIL removal and EFI
free.
Remaining EFIs (i.e., with no corresponding EFD) are processed in
xlog_recover_finish(). An EFD transaction is allocated and the extents
are freed, which transfers ownership of the EFI reference to the EFD
item in the log.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Log recovery attempts to free extents with leftover EFIs in the AIL
after initial processing. If the extent free fails (e.g., due to
unrelated fs corruption), the transaction is cancelled, though it
might not be dirtied at the time. If this is the case, the EFD does
not abort and thus does not release the EFI. This can lead to hangs
as the EFI pins the AIL.
Update xlog_recover_process_efi() to log the EFD in the transaction
before xfs_free_extent() errors are handled to ensure the
transaction is dirty, aborts the EFD and releases the EFI on error.
Since this is a requirement for EFD processing (and consistent with
xfs_bmap_finish()), update the EFD logging helper to do the extent
free and unconditionally log the EFD. This encodes the required EFD
logging behavior into the helper and reduces the likelihood of
errors down the road.
[dchinner: re-add xfs_alloc.h to xfs_log_recover.c to fix build
failure.]
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Freeing an extent in XFS involves logging an EFI (extent free
intention), freeing the actual extent, and logging an EFD (extent
free done). The EFI object is created with a reference count of 2:
one for the current transaction and one for the subsequently created
EFD. Under normal circumstances, the first reference is dropped when
the EFI is unpinned and the second reference is dropped when the EFD
is committed to the on-disk log.
In event of errors or filesystem shutdown, there are various
potential cleanup scenarios depending on the state of the EFI/EFD.
The cleanup scenarios are confusing and racy, as demonstrated by the
following test sequence:
# mount $dev $mnt
# fsstress -d $mnt -n 99999 -p 16 -z -f fallocate=1 \
-f punch=1 -f creat=1 -f unlink=1 &
# sleep 5
# killall -9 fsstress; wait
# godown -f $mnt
# umount
... in which the final umount can hang due to the AIL being pinned
indefinitely by one or more EFI items. This can occur due to several
conditions. For example, if the shutdown occurs after the EFI is
committed to the on-disk log and the EFD committed to the CIL, but
before the EFD committed to the log, the EFD iop_committed() abort
handler does not drop its reference to the EFI. Alternatively,
manual error injection in the xfs_bmap_finish() codepath shows that
if an error occurs after the EFI transaction is committed but before
the EFD is constructed and logged, the EFI is never released from
the AIL.
Update the EFI/EFD item handling code to use a more straightforward
and reliable approach to error handling. If an error occurs after
the EFI transaction is committed and before the EFD is constructed,
release the EFI explicitly from xfs_bmap_finish(). If the EFI
transaction is cancelled, release the EFI in the unlock handler.
Once the EFD is constructed, it is responsible for releasing the EFI
under any circumstances (including whether the EFI item aborts due
to log I/O error). Update the EFD item handlers to release the EFI
if the transaction is cancelled or aborts due to log I/O error.
Finally, update xfs_bmap_finish() to log at least one EFD extent to
the transaction before xfs_free_extent() errors are handled to
ensure the transaction is dirty and EFD item error handling is
triggered.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Some callers need to make error handling decisions based on whether
the current transaction successfully committed or not. Rename
xfs_trans_roll(), add a new parameter and provide a wrapper to
preserve existing callers.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Release of the EFI either occurs based on the reference count or the
extent count. The extent count used is either the count tracked in
the EFI or EFD, depending on the particular situation. In either
case, the count is initialized to the final value and thus always
matches the current efi_next_extent value once the EFI is completely
constructed. For example, the EFI extent count is increased as the
extents are logged in xfs_bmap_finish() and the full free list is
always completely processed. Therefore, the count is guaranteed to
be complete once the EFI transaction is committed. The EFD uses the
efd_nextents counter to release the EFI. This counter is initialized
to the count of the EFI when the EFD is created. Thus the EFD, as
currently used, has no concept of partial EFI release based on
extent count.
Given that the EFI extent count is always released in whole, use of
the extent count for reference counting is unnecessary. Remove this
level of the API and release the EFI based on the core reference
count. The efi_next_extent counter remains because it is still used
to track the slot to log the next extent to free.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Preparation to hide the sb->s_writers internals from xfs and btrfs.
Add 2 trivial define's they can use rather than play with ->s_writers
directly. No changes in btrfs/transaction.o and xfs/xfs_aops.o.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Jan Kara <jack@suse.com>
We can always fill up the bio now, no need to estimate the possible
size based on queue parameters.
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
[hch: rebased and wrote a changelog]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lin <ming.l@ssi.samsung.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Currently we have two different ways to signal an I/O error on a BIO:
(1) by clearing the BIO_UPTODATE flag
(2) by returning a Linux errno value to the bi_end_io callback
The first one has the drawback of only communicating a single possible
error (-EIO), and the second one has the drawback of not beeing persistent
when bios are queued up, and are not passed along from child to parent
bio in the ever more popular chaining scenario. Having both mechanisms
available has the additional drawback of utterly confusing driver authors
and introducing bugs where various I/O submitters only deal with one of
them, and the others have to add boilerplate code to deal with both kinds
of error returns.
So add a new bi_error field to store an errno value directly in struct
bio and remove the existing mechanisms to clean all this up.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This adds a new superblock field, sb_meta_uuid. If set, along with
a new incompat flag, the code will use that field on a V5 filesystem
to compare to metadata UUIDs, which allows us to change the user-
visible UUID at will. Userspace handles the setting and clearing
of the incompat flag as appropriate, as the UUID gets changed; i.e.
setting the user-visible UUID back to the original UUID (as stored in
the new field) will remove the incompatible feature flag.
If the incompat flag is not set, this copies the user-visible UUID into
into the meta_uuid slot in memory when the superblock is read from disk;
the meta_uuid field is not written back to disk in this case.
The remainder of this patch simply switches verifiers, initializers,
etc to use the new sb_meta_uuid field.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The header side of xfs_bit.c is already in libxfs, and the sparse
inode code requires the xfs_next_bit() function so pull in the
xfs_bit.c file so that a sparse inode enabled libxfs compiles
cleanly in userspace.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
xfs_create() and xfs_create_tmpfile() have useless jumps to identical
labels. Simplify them.
Signed-off-by: Jan Kara <jack@suse.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The second and subsequent lines of multi-line logging messages
are not prefixed with the same information as the first line.
Separate messages with newlines into multiple calls to ensure
consistent prefixing and allow easier grep use.
Signed-off-by: Joe Perches <joe@perches.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
When log recovery hits a new transaction, it copies the transaction
header from the expected location in the log to the in-core structure
using the length from the op record header. This length is validated to
ensure it doesn't exceed the length of the record, but not against the
expected size of a transaction header (and thus the size of the in-core
structure). If the on-disk length is corrupted, the associated memcpy()
can overflow, write to unrelated memory and lead to crashes. This has
been reproduced via filesystem fuzzing.
The code currently handles the possibility that the transaction header
is split across two op records. Neither instance accounts for corruption
where the op record length might be larger than the in-core transaction
header. Update both sites to detect such corruption, warn and return an
error from log recovery. Also add some comments and assert that if the
record is split, the copy of the second portion is less than a full
header. Otherwise, this suggests the copy of the second portion could
have overwritten bits from the first and thus that something could be
wrong.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
We have seen somewhat rare reports of the following assert from
xlog_cil_push_background() failing during ltp tests or somewhat
innocuous desktop root fs workloads (e.g., virt operations, initramfs
construction):
ASSERT(!list_empty(&cil->xc_cil));
The reasoning behind the assert is that the transaction has inserted
items to the CIL and hit background push codepath all with
cil->xc_ctx_lock held for reading. This locks out background commit from
emptying the CIL, which acquires the lock for writing. Therefore, the
reasoning is that the items previously inserted in the CIL should still
be present.
The cil->xc_ctx_lock read lock is not sufficient to protect the xc_cil
list, however, due to how CIL insertion is handled.
xlog_cil_insert_items() inserts and reorders the dirty transaction items
to the tail of the CIL under xc_cil_lock. It uses list_move_tail() to
achieve insertion and reordering in the same block of code. This
function removes and reinserts an item to the tail of the list. If a
transaction commits an item that was already logged and thus already
resides in the CIL, and said item is the sole item on the list, the
removal and reinsertion creates a temporary state where the list is
actually empty.
This state is not valid and thus should never be observed by concurrent
transaction commit-side checks in the circumstances outlined above. We
do not want to acquire the xc_cil_lock in all of these instances as it
was previously removed and replaced with a separate push lock for
performance reasons. Therefore, close any races with list_empty() on the
insertion side by ensuring that the list is never in a transient empty
state.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
xfs_bunmapi() doesn't care what type of extent is being freed and
does not look at the XFS_BMAPI_METADATA flag at all. As such we can
remove the XFS_BMAPI_METADATA from all callers that use it.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
We don't log remote attribute contents, and instead write them
synchronously before we commit the block allocation and attribute
tree update transaction. As a result we are writing to the allocated
space before the allcoation has been made permanent.
As a result, we cannot consider this allocation to be a metadata
allocation. Metadata allocation can take blocks from the free list
and so reuse them before the transaction that freed the block is
committed to disk. This behaviour is perfectly fine for journalled
metadata changes as log recovery will ensure the free operation is
replayed before the overwrite, but for remote attribute writes this
is not the case.
Hence we have to consider the remote attribute blocks to contain
data and allocate accordingly. We do this by dropping the
XFS_BMAPI_METADATA flag from the block allocation. This means the
allocation will not use blocks that are on the busy list without
first ensuring that the freeing transaction has been committed to
disk and the blocks removed from the busy list. This ensures we will
never overwrite a freed block without first ensuring that it is
really free.
cc: <stable@vger.kernel.org>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
In recent testing, a system that crashed failed log recovery on
restart with a bad symlink buffer magic number:
XFS (vda): Starting recovery (logdev: internal)
XFS (vda): Bad symlink block magic!
XFS: Assertion failed: 0, file: fs/xfs/xfs_log_recover.c, line: 2060
On examination of the log via xfs_logprint, none of the symlink
buffers in the log had a bad magic number, nor were any other types
of buffer log format headers mis-identified as symlink buffers.
Tracing was used to find the buffer the kernel was tripping over,
and xfs_db identified it's contents as:
000: 5841524d 00000000 00000346 64d82b48 8983e692 d71e4680 a5f49e2c b317576e
020: 00000000 00602038 00000000 006034ce d0020000 00000000 4d4d4d4d 4d4d4d4d
040: 4d4d4d4d 4d4d4d4d 4d4d4d4d 4d4d4d4d 4d4d4d4d 4d4d4d4d 4d4d4d4d 4d4d4d4d
060: 4d4d4d4d 4d4d4d4d 4d4d4d4d 4d4d4d4d 4d4d4d4d 4d4d4d4d 4d4d4d4d 4d4d4d4d
.....
This is a remote attribute buffer, which are notable in that they
are not logged but are instead written synchronously by the remote
attribute code so that they exist on disk before the attribute
transactions are committed to the journal.
The above remote attribute block has an invalid LSN in it - cycle
0xd002000, block 0 - which means when log recovery comes along to
determine if the transaction that writes to the underlying block
should be replayed, it sees a block that has a future LSN and so
does not replay the buffer data in the transaction. Instead, it
validates the buffer magic number and attaches the buffer verifier
to it. It is this buffer magic number check that is failing in the
above assert, indicating that we skipped replay due to the LSN of
the underlying buffer.
The problem here is that the remote attribute buffers cannot have a
valid LSN placed into them, because the transaction that contains
the attribute tree pointer changes and the block allocation that the
attribute data is being written to hasn't yet been committed. Hence
the LSN field in the attribute block is completely unwritten,
thereby leaving the underlying contents of the block in the LSN
field. It could have any value, and hence a future overwrite of the
block by log recovery may or may not work correctly.
Fix this by always writing an invalid LSN to the remote attribute
block, as any buffer in log recovery that needs to write over the
remote attribute should occur. We are protected from having old data
written over the attribute by the fact that freeing the block before
the remote attribute is written will result in the buffer being
marked stale in the log and so all changes prior to the buffer stale
transaction will be cancelled by log recovery.
Hence it is safe to ignore the LSN in the case or synchronously
written, unlogged metadata such as remote attribute blocks, and to
ensure we do that correctly, we need to write an invalid LSN to all
remote attribute blocks to trigger immediate recovery of metadata
that is written over the top.
As a further protection for filesystems that may already have remote
attribute blocks with bad LSNs on disk, change the log recovery code
to always trigger immediate recovery of metadata over remote
attribute blocks.
cc: <stable@vger.kernel.org>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
When modifying the patch series to handle the XFS MMAP_LOCK nesting
of page faults, I botched the conversion of the read page fault
path, and so it is only every calling through the page cache. Re-add
the necessary __dax_fault() call for such files.
Because the get_blocks callback on read faults may not set up the
mapping buffer correctly to allow unwritten extent completion to be
run, we need to allow callers of __dax_fault() to pass a null
complete_unwritten() callback. The DAX code always zeros the
unwritten page when it is read faulted so there are no stale data
exposure issues with not doing the conversion. The only downside
will be the potential for increased CPU overhead on repeated read
faults of the same page. If this proves to be a problem, then the
filesystem needs to fix it's get_block callback and provide a
convert_unwritten() callback to the read fault path.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Pull more vfs updates from Al Viro:
"Assorted VFS fixes and related cleanups (IMO the most interesting in
that part are f_path-related things and Eric's descriptor-related
stuff). UFS regression fixes (it got broken last cycle). 9P fixes.
fs-cache series, DAX patches, Jan's file_remove_suid() work"
[ I'd say this is much more than "fixes and related cleanups". The
file_table locking rule change by Eric Dumazet is a rather big and
fundamental update even if the patch isn't huge. - Linus ]
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (49 commits)
9p: cope with bogus responses from server in p9_client_{read,write}
p9_client_write(): avoid double p9_free_req()
9p: forgetting to cancel request on interrupted zero-copy RPC
dax: bdev_direct_access() may sleep
block: Add support for DAX reads/writes to block devices
dax: Use copy_from_iter_nocache
dax: Add block size note to documentation
fs/file.c: __fget() and dup2() atomicity rules
fs/file.c: don't acquire files->file_lock in fd_install()
fs:super:get_anon_bdev: fix race condition could cause dev exceed its upper limitation
vfs: avoid creation of inode number 0 in get_next_ino
namei: make set_root_rcu() return void
make simple_positive() public
ufs: use dir_pages instead of ufs_dir_pages()
pagemap.h: move dir_pages() over there
remove the pointless include of lglock.h
fs: cleanup slight list_entry abuse
xfs: Correctly lock inode when removing suid and file capabilities
fs: Call security_ops->inode_killpriv on truncate
fs: Provide function telling whether file_remove_privs() will do anything
...
This update contains:
o A new sparse on-disk inode record format to allow small extents to
be used for inode allocation when free space is fragmented.
o DAX support. This includes minor changes to the DAX core code to
fix problems with lock ordering and bufferhead mapping abuse.
o transaction commit interface cleanup
o removal of various unnecessary XFS specific type definitions
o cleanup and optimisation of freelist preparation before allocation
o various minor cleanups
o bug fixes for
- transaction reservation leaks
- incorrect inode logging in unwritten extent conversion
- mmap lock vs freeze ordering
- remote symlink mishandling
- attribute fork removal issues.
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Merge tag 'xfs-for-linus-4.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs
Pul xfs updates from Dave Chinner:
"There's a couple of small API changes to the core DAX code which
required small changes to the ext2 and ext4 code bases, but otherwise
everything is within the XFS codebase.
This update contains:
- A new sparse on-disk inode record format to allow small extents to
be used for inode allocation when free space is fragmented.
- DAX support. This includes minor changes to the DAX core code to
fix problems with lock ordering and bufferhead mapping abuse.
- transaction commit interface cleanup
- removal of various unnecessary XFS specific type definitions
- cleanup and optimisation of freelist preparation before allocation
- various minor cleanups
- bug fixes for
- transaction reservation leaks
- incorrect inode logging in unwritten extent conversion
- mmap lock vs freeze ordering
- remote symlink mishandling
- attribute fork removal issues"
* tag 'xfs-for-linus-4.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs: (49 commits)
xfs: don't truncate attribute extents if no extents exist
xfs: clean up XFS_MIN_FREELIST macros
xfs: sanitise error handling in xfs_alloc_fix_freelist
xfs: factor out free space extent length check
xfs: xfs_alloc_fix_freelist() can use incore perag structures
xfs: remove xfs_caddr_t
xfs: use void pointers in log validation helpers
xfs: return a void pointer from xfs_buf_offset
xfs: remove inst_t
xfs: remove __psint_t and __psunsigned_t
xfs: fix remote symlinks on V5/CRC filesystems
xfs: fix xfs_log_done interface
xfs: saner xfs_trans_commit interface
xfs: remove the flags argument to xfs_trans_cancel
xfs: pass a boolean flag to xfs_trans_free_items
xfs: switch remaining xfs_trans_dup users to xfs_trans_roll
xfs: check min blks for random debug mode sparse allocations
xfs: fix sparse inodes 32-bit compile failure
xfs: add initial DAX support
xfs: add DAX IO path support
...
Pull cgroup writeback support from Jens Axboe:
"This is the big pull request for adding cgroup writeback support.
This code has been in development for a long time, and it has been
simmering in for-next for a good chunk of this cycle too. This is one
of those problems that has been talked about for at least half a
decade, finally there's a solution and code to go with it.
Also see last weeks writeup on LWN:
http://lwn.net/Articles/648292/"
* 'for-4.2/writeback' of git://git.kernel.dk/linux-block: (85 commits)
writeback, blkio: add documentation for cgroup writeback support
vfs, writeback: replace FS_CGROUP_WRITEBACK with SB_I_CGROUPWB
writeback: do foreign inode detection iff cgroup writeback is enabled
v9fs: fix error handling in v9fs_session_init()
bdi: fix wrong error return value in cgwb_create()
buffer: remove unusued 'ret' variable
writeback: disassociate inodes from dying bdi_writebacks
writeback: implement foreign cgroup inode bdi_writeback switching
writeback: add lockdep annotation to inode_to_wb()
writeback: use unlocked_inode_to_wb transaction in inode_congested()
writeback: implement unlocked_inode_to_wb transaction and use it for stat updates
writeback: implement [locked_]inode_to_wb_and_lock_list()
writeback: implement foreign cgroup inode detection
writeback: make writeback_control track the inode being written back
writeback: relocate wb[_try]_get(), wb_put(), inode_{attach|detach}_wb()
mm: vmscan: disable memcg direct reclaim stalling if cgroup writeback support is in use
writeback: implement memcg writeback domain based throttling
writeback: reset wb_domain->dirty_limit[_tstmp] when memcg domain size changes
writeback: implement memcg wb_domain
writeback: update wb_over_bg_thresh() to use wb_domain aware operations
...
Pull core block IO update from Jens Axboe:
"Nothing really major in here, mostly a collection of smaller
optimizations and cleanups, mixed with various fixes. In more detail,
this contains:
- Addition of policy specific data to blkcg for block cgroups. From
Arianna Avanzini.
- Various cleanups around command types from Christoph.
- Cleanup of the suspend block I/O path from Christoph.
- Plugging updates from Shaohua and Jeff Moyer, for blk-mq.
- Eliminating atomic inc/dec of both remaining IO count and reference
count in a bio. From me.
- Fixes for SG gap and chunk size support for data-less (discards)
IO, so we can merge these better. From me.
- Small restructuring of blk-mq shared tag support, freeing drivers
from iterating hardware queues. From Keith Busch.
- A few cfq-iosched tweaks, from Tahsin Erdogan and me. Makes the
IOPS mode the default for non-rotational storage"
* 'for-4.2/core' of git://git.kernel.dk/linux-block: (35 commits)
cfq-iosched: fix other locations where blkcg_to_cfqgd() can return NULL
cfq-iosched: fix sysfs oops when attempting to read unconfigured weights
cfq-iosched: move group scheduling functions under ifdef
cfq-iosched: fix the setting of IOPS mode on SSDs
blktrace: Add blktrace.c to BLOCK LAYER in MAINTAINERS file
block, cgroup: implement policy-specific per-blkcg data
block: Make CFQ default to IOPS mode on SSDs
block: add blk_set_queue_dying() to blkdev.h
blk-mq: Shared tag enhancements
block: don't honor chunk sizes for data-less IO
block: only honor SG gap prevention for merges that contain data
block: fix returnvar.cocci warnings
block, dm: don't copy bios for request clones
block: remove management of bi_remaining when restoring original bi_end_io
block: replace trylock with mutex_lock in blkdev_reread_part()
block: export blkdev_reread_part() and __blkdev_reread_part()
suspend: simplify block I/O handling
block: collapse bio bit space
block: remove unused BIO_RW_BLOCK and BIO_EOF flags
block: remove BIO_EOPNOTSUPP
...
Currently XFS calls file_remove_privs() without holding i_mutex. This is
wrong because that function can end up messing with file permissions and
file capabilities stored in xattrs for which we need i_mutex held.
Fix the problem by grabbing iolock exclusively when we will need to
change anything in permissions / xattrs.
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
file_remove_suid() is a misnomer since it removes also file capabilities
stored in xattrs and sets S_NOSEC flag. Also should_remove_suid() tells
something else than whether file_remove_suid() call is necessary which
leads to bugs.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The xfs_attr3_root_inactive() call from xfs_attr_inactive() assumes that
attribute blocks exist to invalidate. It is possible to have an
attribute fork without extents, however. Consider the case where the
attribute fork is created towards the beginning of xfs_attr_set() but
some part of the subsequent attribute set fails.
If an inode in such a state hits xfs_attr_inactive(), it eventually
calls xfs_dabuf_map() and possibly xfs_bmapi_read(). The former emits a
filesystem corruption warning, returns an error that bubbles back up to
xfs_attr_inactive(), and leads to destruction of the in-core attribute
fork without an on-disk reset. If the inode happens to make it back
through xfs_inactive() in this state (e.g., via a concurrent bulkstat
that cycles the inode from the reclaim state and releases it), i_afp
might not exist when xfs_bmapi_read() is called and causes a NULL
dereference panic.
A '-p 2' fsstress run to ENOSPC on a relatively small fs (1GB)
reproduces these problems. The behavior is a regression caused by:
6dfe5a0 xfs: xfs_attr_inactive leaves inconsistent attr fork state behind
... which removed logic that avoided the attribute extent truncate when
no extents exist. Restore this logic to ensure the attribute fork is
destroyed and reset correctly if it exists without any allocated
extents.
cc: stable@vger.kernel.org # 3.12 to 4.0.x
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Pull vfs updates from Al Viro:
"In this pile: pathname resolution rewrite.
- recursion in link_path_walk() is gone.
- nesting limits on symlinks are gone (the only limit remaining is
that the total amount of symlinks is no more than 40, no matter how
nested).
- "fast" (inline) symlinks are handled without leaving rcuwalk mode.
- stack footprint (independent of the nesting) is below kilobyte now,
about on par with what it used to be with one level of nested
symlinks and ~2.8 times lower than it used to be in the worst case.
- struct nameidata is entirely private to fs/namei.c now (not even
opaque pointers are being passed around).
- ->follow_link() and ->put_link() calling conventions had been
changed; all in-tree filesystems converted, out-of-tree should be
able to follow reasonably easily.
For out-of-tree conversions, see Documentation/filesystems/porting
for details (and in-tree filesystems for examples of conversion).
That has sat in -next since mid-May, seems to survive all testing
without regressions and merges clean with v4.1"
* 'for-linus-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (131 commits)
turn user_{path_at,path,lpath,path_dir}() into static inlines
namei: move saved_nd pointer into struct nameidata
inline user_path_create()
inline user_path_parent()
namei: trim do_last() arguments
namei: stash dfd and name into nameidata
namei: fold path_cleanup() into terminate_walk()
namei: saner calling conventions for filename_parentat()
namei: saner calling conventions for filename_create()
namei: shift nameidata down into filename_parentat()
namei: make filename_lookup() reject ERR_PTR() passed as name
namei: shift nameidata inside filename_lookup()
namei: move putname() call into filename_lookup()
namei: pass the struct path to store the result down into path_lookupat()
namei: uninline set_root{,_rcu}()
namei: be careful with mountpoint crossings in follow_dotdot_rcu()
Documentation: remove outdated information from automount-support.txt
get rid of assorted nameidata-related debris
lustre: kill unused helper
lustre: kill unused macro (LOOKUP_CONTINUE)
...
We no longer calculate the minimum freelist size from the on-disk
AGF, so we don't need the macros used for this. That means the
nested macros can be cleaned up, and turn this into an actual
function so the logic is clear and concise. This will make it much
easier to add support for the rmap btree when the time comes.
This also gets rid of the XFS_AG_MAXLEVELS macro used by these
freelist macros as it is simply a wrapper around a single variable.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The error handling is currently an inconsistent mess as every error
condition handles return values and releasing buffers individually.
Clean this up by using gotos and a sane error label stack.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The longest extent length checks in xfs_alloc_fix_freelist() are now
essentially identical. Factor them out into a helper function, so we
know they are checking exactly the same thing before and after we
lock the AGF.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
At the moment, xfs_alloc_fix_freelist() uses a mix of per-ag based
access and agf buffer based access to freelist and space usage
information. However, once the AGF buffer is locked inside this
function, it is guaranteed that both the in-memory and on-disk
values are identical. xfs_alloc_fix_freelist() doesn't modify the
values in the structures directly, so it is a read-only user of the
infomration, and hence can use the per-ag structure exclusively for
determining what it should do.
This opens up an avenue for cleaning up a lot of duplicated logic
whose only difference is the structure it gets the data from, and in
doing so removes a lot of needless byte swapping overhead when
fixing up the free list.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Just use char pointers directly instead of the confusing typedef to a
pointer type.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Compared to char pointers this saves us a lot of casting effort. Also
add another local variable to make the code easier to read.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
This avoids all kinds of unessecary casts in an envrionment like Linux where
we can assume that pointer arithmetics are support on void pointers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
We can simply use a void pointer to pass a long return addresses in the
debugging helpers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Replace uses of __psint_t with the proper uintptr_t and ptrdiff_t types,
and remove the defintions of __psint_t and __psunsigned_t.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
If we create a CRC filesystem, mount it, and create a symlink with
a path long enough that it can't live in the inode, we get a very
strange result upon remount:
# ls -l mnt
total 4
lrwxrwxrwx. 1 root root 929 Jun 15 16:58 link -> XSLM
XSLM is the V5 symlink block header magic (which happens to be
followed by a NUL, so the string looks terminated).
xfs_readlink_bmap() advanced cur_chunk by the size of the header
for CRC filesystems, but never actually used that pointer; it
kept reading from bp->b_addr, which is the start of the block,
rather than the start of the symlink data after the header.
Looks like this problem goes back to v3.10.
Fixing this gets us reading the proper link target, again.
Cc: stable@vger.kernel.org
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Instead of the confusing flags argument pass a boolean flag to indicate if
we want to release or regrant a log reservation.
Also ensure that xfs_log_done always drop the reference on the log ticket,
to both simplify the code and make the logic in xfs_trans_roll easier
to understand.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The flags argument to xfs_trans_commit is not useful for most callers, as
a commit of a transaction without a permanent log reservation must pass
0 here, and all callers for a transaction with a permanent log reservation
except for xfs_trans_roll must pass XFS_TRANS_RELEASE_LOG_RES. So remove
the flags argument from the public xfs_trans_commit interfaces, and
introduce low-level __xfs_trans_commit variant just for xfs_trans_roll
that regrants a log reservation instead of releasing it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
xfs_trans_cancel takes two flags arguments: XFS_TRANS_RELEASE_LOG_RES and
XFS_TRANS_ABORT. Both of them are a direct product of the transaction
state, and can be deducted:
- any dirty transaction needs XFS_TRANS_ABORT to be properly canceled,
and XFS_TRANS_ABORT is a noop for a transaction that is not dirty.
- any transaction with a permanent log reservation needs
XFS_TRANS_RELEASE_LOG_RES to be properly canceled, and passing
XFS_TRANS_RELEASE_LOG_RES for a transaction without a permanent
log reservation is invalid.
So just remove the flags argument and do the right thing.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The flags value always was 0 or XFS_TRANS_ABORT. Switch to a bool
parameter to allow further cleanups.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
We have three remaining callers of xfs_trans_dup:
- xfs_itruncate_extents which open codes xfs_trans_roll
- xfs_bmap_finish doesn't have an xfs_inode argument and thus leaves
attaching them to it's callers, but otherwise is identical to
xfs_trans_roll
- xfs_dir_ialloc looks at the log reservations in the old xfs_trans
structure instead of the log reservation parameters, but otherwise
is identical to xfs_trans_roll.
By allowing a NULL xfs_inode argument to xfs_trans_roll we can switch
these three remaining users over to xfs_trans_roll and mark xfs_trans_dup
static.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The inode allocator enables random sparse inode chunk allocations in
DEBUG mode to facilitate testing. Sparse inode allocations are not
always possible, however, depending on the fs geometry. For example,
there is no possibility for a sparse inode allocation on filesystems
where the block size is large enough to fit one or more inode chunks
within a single block.
Fix up the DEBUG mode sparse inode allocation logic to trigger random
sparse allocations only when the geometry of the fs allows it.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The kbuild test robot reports the following compilation failure with a
32-bit kernel configuration:
fs/built-in.o: In function `xfs_ifree_cluster':
>> xfs_inode.c:(.text+0x17ac84): undefined reference to `__umoddi3'
This is due to the use of the modulus operator on a 64-bit variable in
the ASSERT() added as part of the following commit:
xfs: skip unallocated regions of inode chunks in xfs_ifree_cluster()
This ASSERT() simply checks that the offset of the inode in a sparse
cluster is appropriately aligned. Since the maximum inode record offset
is 63 (for a 64 inode record) and the calculated offset here should be
something less than that, just use a 32-bit variable to store the offset
and call the do_mod() helper.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Add initial DAX support to XFS. To do this we need a new mount
option to turn DAX on filesystem, and we need to propagate this into
the inode flags whenever an inode is instantiated so that the
per-inode checks throughout the code Do The Right Thing.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
DAX does not do buffered IO (can't buffer direct access!) and hence
all read/write IO is vectored through the direct IO path. Hence we
need to add the DAX IO path callouts to the direct IO
infrastructure.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
When we truncate a DAX file, we need to call through the DAX page
truncation path rather than through block_truncate_page() so that
mappings and block zeroing are all handled correctly. Otherwise,
truncate does not need to change.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Add initial support for DAX block zeroing operations to XFS. DAX
cannot use buffered IO through the page cache for zeroing, nor do we
need to issue IO for uncached block zeroing. In both cases, we can
simply call out to the dax block zeroing function.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Add the initial support for DAX file operations to XFS. This
includes the necessary block allocation and mmap page fault hooks
for DAX to function.
Note that there are changes to the splice interfaces to ensure that
for DAX splice avoids direct page cache manipulations and instead
takes the DAX IO paths for read/write operations.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Lock ordering for the new mmap lock needs to be:
mmap_sem
sb_start_pagefault
i_mmap_lock
page lock
<fault processsing>
Right now xfs_vm_page_mkwrite gets this the wrong way around,
While technically it cannot deadlock due to the current freeze
ordering, it's still a landmine that might explode if we change
anything in future. Hence we need to nest the locks correctly.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
With the planned cgroup writeback support, backing-dev related
declarations will be more widely used across block and cgroup;
unfortunately, including backing-dev.h from include/linux/blkdev.h
makes cyclic include dependency quite likely.
This patch separates out backing-dev-defs.h which only has the
essential definitions and updates blkdev.h to include it. c files
which need access to more backing-dev details now include
backing-dev.h directly. This takes backing-dev.h off the common
include dependency chain making it a lot easier to use it across block
and cgroup.
v2: fs/fat build failure fixed.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Jens Axboe <axboe@fb.com>
When modifying PG_Dirty on cached file pages, update the new
MEM_CGROUP_STAT_DIRTY counter. This is done in the same places where
global NR_FILE_DIRTY is managed. The new memcg stat is visible in the
per memcg memory.stat cgroupfs file. The most recent past attempt at
this was http://thread.gmane.org/gmane.linux.kernel.cgroups/8632
The new accounting supports future efforts to add per cgroup dirty
page throttling and writeback. It also helps an administrator break
down a container's memory usage and provides evidence to understand
memcg oom kills (the new dirty count is included in memcg oom kill
messages).
The ability to move page accounting between memcg
(memory.move_charge_at_immigrate) makes this accounting more
complicated than the global counter. The existing
mem_cgroup_{begin,end}_page_stat() lock is used to serialize move
accounting with stat updates.
Typical update operation:
memcg = mem_cgroup_begin_page_stat(page)
if (TestSetPageDirty()) {
[...]
mem_cgroup_update_page_stat(memcg)
}
mem_cgroup_end_page_stat(memcg)
Summary of mem_cgroup_end_page_stat() overhead:
- Without CONFIG_MEMCG it's a no-op
- With CONFIG_MEMCG and no inter memcg task movement, it's just
rcu_read_lock()
- With CONFIG_MEMCG and inter memcg task movement, it's
rcu_read_lock() + spin_lock_irqsave()
A memcg parameter is added to several routines because their callers
now grab mem_cgroup_begin_page_stat() which returns the memcg later
needed by for mem_cgroup_update_page_stat().
Because mem_cgroup_begin_page_stat() may disable interrupts, some
adjustments are needed:
- move __mark_inode_dirty() from __set_page_dirty() to its caller.
__mark_inode_dirty() locking does not want interrupts disabled.
- use spin_lock_irqsave(tree_lock) rather than spin_lock_irq() in
__delete_from_page_cache(), replace_page_cache_page(),
invalidate_complete_page2(), and __remove_mapping().
text data bss dec hex filename
8925147 1774832 1785856 12485835 be84cb vmlinux-!CONFIG_MEMCG-before
8925339 1774832 1785856 12486027 be858b vmlinux-!CONFIG_MEMCG-after
+192 text bytes
8965977 1784992 1785856 12536825 bf4bf9 vmlinux-CONFIG_MEMCG-before
8966750 1784992 1785856 12537598 bf4efe vmlinux-CONFIG_MEMCG-after
+773 text bytes
Performance tests run on v4.0-rc1-36-g4f671fe2f952. Lower is better for
all metrics, they're all wall clock or cycle counts. The read and write
fault benchmarks just measure fault time, they do not include I/O time.
* CONFIG_MEMCG not set:
baseline patched
kbuild 1m25.030000(+-0.088% 3 samples) 1m25.426667(+-0.120% 3 samples)
dd write 100 MiB 0.859211561 +-15.10% 0.874162885 +-15.03%
dd write 200 MiB 1.670653105 +-17.87% 1.669384764 +-11.99%
dd write 1000 MiB 8.434691190 +-14.15% 8.474733215 +-14.77%
read fault cycles 254.0(+-0.000% 10 samples) 253.0(+-0.000% 10 samples)
write fault cycles 2021.2(+-3.070% 10 samples) 1984.5(+-1.036% 10 samples)
* CONFIG_MEMCG=y root_memcg:
baseline patched
kbuild 1m25.716667(+-0.105% 3 samples) 1m25.686667(+-0.153% 3 samples)
dd write 100 MiB 0.855650830 +-14.90% 0.887557919 +-14.90%
dd write 200 MiB 1.688322953 +-12.72% 1.667682724 +-13.33%
dd write 1000 MiB 8.418601605 +-14.30% 8.673532299 +-15.00%
read fault cycles 266.0(+-0.000% 10 samples) 266.0(+-0.000% 10 samples)
write fault cycles 2051.7(+-1.349% 10 samples) 2049.6(+-1.686% 10 samples)
* CONFIG_MEMCG=y non-root_memcg:
baseline patched
kbuild 1m26.120000(+-0.273% 3 samples) 1m25.763333(+-0.127% 3 samples)
dd write 100 MiB 0.861723964 +-15.25% 0.818129350 +-14.82%
dd write 200 MiB 1.669887569 +-13.30% 1.698645885 +-13.27%
dd write 1000 MiB 8.383191730 +-14.65% 8.351742280 +-14.52%
read fault cycles 265.7(+-0.172% 10 samples) 267.0(+-0.000% 10 samples)
write fault cycles 2070.6(+-1.512% 10 samples) 2084.4(+-2.148% 10 samples)
As expected anon page faults are not affected by this patch.
tj: Updated to apply on top of the recent cancel_dirty_page() changes.
Signed-off-by: Sha Zhengju <handai.szj@gmail.com>
Signed-off-by: Greg Thelen <gthelen@google.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
Fixed two missing spaces.
Signed-off-by: Nan Jia <jiananmail@gmail.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The commit:
a9273ca5 xfs: convert attr to use unsigned names
added these (unsigned char *) casts, but then the _SIZE macros
return "7" - size of a pointer minus one - not the length of
the string. This is harmless in the kernel, because the _SIZE
macros are not used, but as we sync up with userspace, this will
matter.
I don't think the cast is necessary; i.e. assigning the string
literal to an unsigned char *, or passing it to a function
expecting an unsigned char *, should be ok, right?
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Al Viro reports that generic/231 fails frequently on XFS and bisected
the problem to the following commit:
5d11fb4b xfs: rework zero range to prevent invalid i_size updates
... which is just the first commit that happens to cause fsx to
reproduce the problem. fsx reproduces via zero range calls. The
aforementioned commit overhauls zero range to use hole punch and
fallocate. As it turns out, the problem is reproducible on demand using
basic hole punch as follows:
$ mkfs.xfs -f -m crc=1,finobt=1 <dev>
$ mount <dev> /mnt -o uquota
$ xfs_io -f -c "falloc 0 50m" /mnt/file
$ for i in $(seq 1 20); do xfs_io -c "fpunch ${i}m 32k" /mnt/file; done
$ rm -f /mnt/file
$ repquota -us /mnt
...
User used soft hard grace used soft hard grace
----------------------------------------------------------------------
root -- 32K 0K 0K 3 0 0
A file is allocated with a single 50m extent. The extent count increases
via hole punches until the bmap converts to btree format. The file is
removed but quota reports 32k of space usage for the user. This
reservation is effectively leaked for the lifetime of the mount.
The reason this occurs is because the quota block reservation tracking
is confused when a transaction happens to free and allocate blocks at
the same time. Consider the following sequence of events:
- tp is allocated from xfs_free_file_space() and reserves several blocks
for btree management. Blocks are reserved against the dquot and marked
as such in the transaction (qtrx->qt_blk_res).
- 8 blocks are accounted free when the 32k range is punched out.
xfs_trans_mod_dquot() is called with XFS_TRANS_DQ_BCOUNT and sets
->qt_bcount_delta to -8.
- Subsequently, a block is allocated against the same transaction by
xfs_bmap_extents_to_btree() for btree conversion. A call to
xfs_trans_mod_dquot() increases qt_blk_res_used to 1 and qt_bcount_delta
to -7.
- The transaction is dup'd and committed by xfs_bmap_finish().
xfs_trans_dup_dqinfo() sets the first transaction up such that it has a
matching qt_blk_res and qt_blk_res_used of 1. The remaining unused
reservation is transferred to the duplicate tp.
When the transactions are committed, the dquots are fixed up in
xfs_trans_apply_dquot_deltas() according to one of two methods:
1.) If the transaction holds a block reservation (->qt_blk_res != 0),
_only_ the unused portion reservation is unaccounted from the dquot.
Note that the tp duplication behavior of xfs_bmap_finish() makes it such
that qt_blk_res is typically 0 for tp's with unused reservation.
2.) Otherwise, the dquot is fixed up based on the block delta
(->qt_bcount_delta) created by the transaction.
Therefore, if a transaction has a negative qt_bcount_delta and positive
qt_blk_res_used, the former set of blocks that have been removed from
the file are never factored out of the in-core dquot reservation.
Instead, *_apply_dquot_deltas() sees 1 block used out of a 1 block
reservation and believes there is nothing to fix up. The on-disk
d_bcount is updated independently from qt_bcount_delta, and thus is
correct (and allows the quota usage to correct on remount).
To deal with this situation, we effectively want the "used reservation"
part of the transaction to be consistent with any freed blocks with
respect to quota tracking. For example, if 8 blocks are freed, the
subsequent single block allocation does not need to consume the initial
reservation made by the tp. Instead, it simply borrows one from the
previously freed. One possible implementation of such borrowing is to
avoid the blks_res_used increment when bcount_delta is negative. This
alone is flawed logic in that it only handles the case where blocks are
freed before allocated, however.
Rather than add more complexity to manage synchronization between
bcount_delta and blks_res_used, kill the latter entirely. blk_res_used
is only updated in one place and always in sync with delta_bcount.
Therefore, the net block reservation consumption of the transaction is
always available from bcount_delta. Calculate the reservation
consumption on the fly where necessary based on whether the tp has a
reservation and results in a positive net block delta on the inode.
Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The fsync() requirements for crash consistency on XFS are to flush file
data and force any in-core inode updates to the log. We currently check
whether the inode is pinned to identify whether the log needs to be
forced, since a non-zero pin count generally represents an inode that
has transactions awaiting a flush to the on-disk log.
This is not sufficient in all cases, however. Reports of xfstests test
generic/311 failures on ppc64/s390x hosts have identified failures to
fsync outstanding inode modifications due to the inode not being pinned
at the time of the fsync. This occurs because certain bmap updates can
complete by logging bmapbt buffers but without ever dirtying (and thus
pinning) the core inode. The following is a specific incarnation of this
problem:
$ mount $dev /mnt -o noatime,nobarrier
$ for i in $(seq 0 2 31); do \
xfs_io -f -c "falloc $((i * 32768)) 32k" -c fsync /mnt/file; \
done
$ xfs_io -c "pwrite -S 0 80k 16k" -c fsync -c "pwrite 76k 4k" -c fsync /mnt/file; \
hexdump /mnt/file; \
./xfstests-dev/src/godown /mnt
...
0000000 0000 0000 0000 0000 0000 0000 0000 0000
*
0013000 cdcd cdcd cdcd cdcd cdcd cdcd cdcd cdcd
*
0014000 0000 0000 0000 0000 0000 0000 0000 0000
*
00f8000
$ umount /mnt; mount ...
$ hexdump /mnt/file
0000000 0000 0000 0000 0000 0000 0000 0000 0000
*
00f8000
In short, the unwritten extent conversion for the last write is lost
despite the fact that an fsync executed before the filesystem was
shutdown. Note that this is impossible to reproduce on v5 supers due to
unconditional time callbacks for di_changecount and highly difficult to
reproduce on CONFIG_HZ=1000 kernels due to those same callbacks
frequently updating cmtime prior to the bmap update. CONFIG_HZ=100
reduces timer granularity enough to increase the odds that time updates
are skipped and allows this to reproduce within a handful of attempts.
To deal with this problem, unconditionally log the core in the unwritten
extent conversion path. Fix up logflags after the extent conversion to
keep the extent update code consistent with the other extent update
helpers. This fixup is not necessary for the other (hole, delay) extent
helpers because they execute in the block allocation codepath, which
already logs the inode for other reasons (e.g., for di_nblocks).
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Enable mounting of filesystems with sparse inode support enabled. Add
the incompat. feature bit to the *_ALL mask.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
xfs_ifree_cluster() is called to mark all in-memory inodes and inode
buffers as stale. This occurs after we've removed the inobt records and
dropped any references of inobt data. xfs_ifree_cluster() uses the
starting inode number to walk the namespace of inodes expected for a
single chunk a cluster buffer at a time. The cluster buffer disk
addresses are calculated by decoding the sequential inode numbers
expected from the chunk.
The problem with this approach is that if the inode chunk being removed
is a sparse chunk, not all of the buffer addresses that are calculated
as part of this sequence may be inode clusters. Attempting to acquire
the buffer based on expected inode characterstics (i.e., cluster length)
can lead to errors and is generally incorrect.
We already use a couple variables to carry requisite state from
xfs_difree() to xfs_ifree_cluster(). Rather than add a third, define a
new internal structure to carry the existing parameters through these
functions. Add an alloc field that represents the physical allocation
bitmap of inodes in the chunk being removed. Modify xfs_ifree_cluster()
to check each inode against the bitmap and skip the clusters that were
never allocated as real inodes on disk.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
An inode chunk is currently added to the transaction free list based on
a simple fsb conversion and hardcoded chunk length. The nature of sparse
chunks is such that the physical chunk of inodes on disk may consist of
one or more discontiguous parts. Blocks that reside in the holes of the
inode chunk are not inodes and could be allocated to any other use or
not allocated at all.
Refactor the existing xfs_bmap_add_free() call into the
xfs_difree_inode_chunk() helper. The new helper uses the existing
calculation if a chunk is not sparse. Otherwise, use the inobt record
holemask to free the contiguous regions of the chunk.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Inode allocation from an existing record with free inodes traditionally
selects the first inode available according to the ir_free mask. With
sparse inode chunks, the ir_free mask could refer to an unallocated
region. We must mask the unallocated regions out of ir_free before using
it to select a free inode in the chunk.
Update the xfs_inobt_first_free_inode() helper to find the first free
inode available of the allocated regions of the inode chunk.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Sparse inode allocations generally only occur when full inode chunk
allocation fails. This requires some level of filesystem space usage and
fragmentation.
For filesystems formatted with sparse inode chunks enabled, do random
sparse inode chunk allocs when compiled in DEBUG mode to increase test
coverage.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
xfs_ialloc_ag_alloc() makes several attempts to allocate a full inode
chunk. If all else fails, reduce the allocation to the sparse length and
alignment and attempt to allocate a sparse inode chunk.
If sparse chunk allocation succeeds, check whether an inobt record
already exists that can track the chunk. If so, inherit and update the
existing record. Otherwise, insert a new record for the sparse chunk.
Create helpers to align sparse chunk inode records and insert or update
existing records in the inode btrees. The xfs_inobt_insert_sprec()
helper implements the merge or update semantics required for sparse
inode records with respect to both the inobt and finobt. To update the
inobt, either insert a new record or merge with an existing record. To
update the finobt, use the updated inobt record to either insert or
replace an existing record.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The inobt record holemask field is a condensed data type designed to fit
into the existing on-disk record and is zero based (allocated regions
are set to 0, sparse regions are set to 1) to provide backwards
compatibility. This makes the type somewhat complex for use in higher
level inode manipulations such as individual inode allocation, etc.
Rather than foist the complexity of dealing with this field to every bit
of logic that requires inode granular information, create a helper to
convert the holemask to an inode allocation bitmap. The inode allocation
bitmap is inode granularity similar to the inobt record free mask and
indicates which inodes of the chunk are physically allocated on disk,
irrespective of whether the inode is considered allocated or free by the
filesystem.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Recovery of icreate transactions assumes hardcoded values for the inode
count and chunk length.
Sparse inode chunks are allocated in units of m_ialloc_min_blks. Update
the icreate validity checks to allow for appropriately sized inode
chunks and verify the inode count matches what is expected based on the
extent length rather than assuming a hardcoded count.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
v5 superblocks use an ordered log item for logging the initialization of
inode chunks. The icreate log item is currently hardcoded to an inode
count of 64 inodes.
The agbno and extent length are used to initialize the inode chunk from
log recovery. While an incorrect inode count does not lead to bad inode
chunk initialization, we should pass the correct inode count such that log
recovery has enough data to perform meaningful validity checks on the
chunk.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The bulkstat and inumbers mechanisms make the assumption that inode
records consist of a full 64 inode chunk in several places. For example,
this is used to track how many inodes have been processed overall as
well as to determine whether a record has allocated inodes that must be
handled.
This assumption is invalid for sparse inode records. While sparse inodes
will be marked as free in the ir_free mask, they are not accounted as
free in ir_freecount because they cannot be allocated. Therefore,
ir_freecount may be less than 64 inodes in an inode record for which all
physically allocated inodes are free (and in turn ir_freecount < 64 does
not signify that the record has allocated inodes).
The new in-core inobt record format includes the ir_count field. This
holds the number of true, physical inodes tracked by the record. The
in-core ir_count field is always valid as it is hardcoded to
XFS_INODES_PER_CHUNK when sparse inodes is not enabled. Use ir_count to
handle inode records correctly in bulkstat in a generic manner.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The inode btrees track 64 inodes per record regardless of inode size.
Thus, inode chunks on disk vary in size depending on the size of the
inodes. This creates a contiguous allocation requirement for new inode
chunks that can be difficult to satisfy on an aged and fragmented (free
space) filesystems.
The inode record freecount currently uses 4 bytes on disk to track the
free inode count. With a maximum freecount value of 64, only one byte is
required. Convert the freecount field to a single byte and use two of
the remaining 3 higher order bytes left for the hole mask field. Use the
final leftover byte for the total count field.
The hole mask field tracks holes in the chunks of physical space that
the inode record refers to. This facilitates the sparse allocation of
inode chunks when contiguous chunks are not available and allows the
inode btrees to identify what portions of the chunk contain valid
inodes. The total count field contains the total number of valid inodes
referred to by the record. This can also be deduced from the hole mask.
The count field provides clarity and redundancy for internal record
verification.
Note that neither of the new fields can be written to disk on fs'
without sparse inode support. Doing so writes to the high-order bytes of
freecount and causes corruption from the perspective of older kernels.
The on-disk inobt record data structure is updated with a union to
distinguish between the original, "full" format and the new, "sparse"
format. The conversion routines to get, insert and update records are
updated to translate to and from the on-disk record accordingly such
that freecount remains a 4-byte value on non-supported fs, yet the new
fields of the in-core record are always valid with respect to the
record. This means that higher level code can refer to the current
in-core record format unconditionally and lower level code ensures that
records are translated to/from disk according to the capabilities of the
fs.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Define an fs geometry bit for sparse inode chunks such that the
characteristic of the fs can be identified by userspace.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The sparse inode chunks feature uses the helper function to enable the
allocation of sparse inode chunks. The incompatible feature bit is set
on disk at mkfs time to prevent mount from unsupported kernels.
Also, enforce the inode alignment requirements required for sparse inode
chunks at mount time. When enabled, full inode chunks (and all inode
record) alignment is increased from cluster size to inode chunk size.
Sparse inode alignment must match the cluster size of the fs. Both
superblock alignment fields are set as such by mkfs when sparse inode
support is enabled.
Finally, warn that sparse inode chunks is an experimental feature until
further notice.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
xfs_ialloc_ag_select() iterates through the allocation groups looking
for free inodes or free space to determine whether to allow an inode
allocation to proceed. If no free inodes are available, it assumes that
an AG must have an extent longer than mp->m_ialloc_blks.
Sparse inode chunk support currently allows for allocations smaller than
the traditional inode chunk size specified in m_ialloc_blks. The current
minimum sparse allocation is set in the superblock sb_spino_align field
at mkfs time. Create a new m_ialloc_min_blks field in xfs_mount and use
this to represent the minimum supported allocation size for inode
chunks. Initialize m_ialloc_min_blks at mount time based on whether
sparse inodes are supported.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Add sb_spino_align to the superblock to specify sparse inode chunk
alignment. This also currently represents the minimum allowable sparse
chunk allocation size.
Signed-off-by: Brian Foster <bfoster@redhat.com>
The block allocator supports various arguments to tweak block allocation
behavior and set allocation requirements. The sparse inode chunk feature
introduces a new requirement not supported by the current arguments.
Sparse inode allocations must convert or merge into an inode record that
describes a fixed length chunk (64 inodes x inodesize). Full inode chunk
allocations by definition always result in valid inode records. Sparse
chunk allocations are smaller and the associated records can refer to
blocks not owned by the inode chunk. This model can result in invalid
inode records in certain cases.
For example, if a sparse allocation occurs near the start of an AG, the
aligned inode record for that chunk might refer to agbno 0. If an
allocation occurs towards the end of the AG and the AG size is not
aligned, the inode record could refer to blocks beyond the end of the
AG. While neither of these scenarios directly result in corruption, they
both insert invalid inode records and at minimum cause repair to
complain, are unlikely to merge into full chunks over time and set land
mines for other areas of code.
To guarantee sparse inode chunk allocation creates valid inode records,
support the ability to specify an agbno range limit for
XFS_ALLOCTYPE_NEAR_BNO block allocations. The min/max agbno's are
specified in the allocation arguments and limit the block allocation
algorithms to that range. The starting 'agbno' hint is clamped to the
range if the specified agbno is out of range. If no sufficient extent is
available within the range, the allocation fails. For backwards
compatibility, the min/max fields can be initialized to 0 to disable
range limiting (e.g., equivalent to min=0,max=agsize).
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
xfs_difree_inobt() uses logic in a couple places that assume inobt
records refer to fully allocated chunks. Specifically, the use of
mp->m_ialloc_inos can cause problems for inode chunks that are sparsely
allocated. Sparse inode chunks can, by definition, define a smaller
number of inodes than a full inode chunk.
Fix the logic that determines whether an inode record should be removed
from the inobt to use the ir_free mask rather than ir_freecount. Fix the
agi counters modification to use ir_freecount to add the actual number
of inodes freed rather than assuming a full inode chunk.
Also make sure that we preserve the behavior to not remove inode chunks
if the block size is large enough for multiple inode chunks (e.g.,
bsize=64k, isize=512). This behavior was previously implicit in that in
such configurations, ir.freecount of a single record never matches
m_ialloc_inos. Hence, add some comments as well.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Inode allocation from sparse inode records must filter the ir_free mask
against ir_holemask. In preparation for this requirement, create a
helper to allocate an individual inode from an inode record.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
XFS uses the internal tmpfile() infrastructure for the whiteout inode
used for RENAME_WHITEOUT operations. For tmpfile inodes, XFS allocates
the inode, drops di_nlink, adds the inode to the agi unlinked list,
calls d_tmpfile() which correspondingly drops i_nlink of the vfs inode,
and then finishes the common inode setup (e.g., clear I_NEW and unlock).
The d_tmpfile() call was originally made inxfs_create_tmpfile(), but was
pulled up out of that function as part of the following commit to
resolve a deadlock issue:
330033d6 xfs: fix tmpfile/selinux deadlock and initialize security
As a result, callers of xfs_create_tmpfile() are responsible for either
calling d_tmpfile() or fixing up i_nlink appropriately. The whiteout
tmpfile allocation helper does neither. As a result, the vfs ->i_nlink
becomes inconsistent with the on-disk ->di_nlink once xfs_rename() links
it back into the source dentry and calls xfs_bumplink().
Update the assert in xfs_rename() to help detect this problem in the
future and update xfs_rename_alloc_whiteout() to decrement the link
count as part of the manual tmpfile inode setup.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
It was missed when we converted everything in XFs to use negative error
numbers, so fix it now. Bug introduced in 3.17 by commit 2451337 ("xfs: global
error sign conversion"), and should go back to stable kernels.
Thanks to Brian Foster for noticing it.
cc: <stable@vger.kernel.org> # 3.17, 3.18, 3.19, 4.0
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
xfs_attr_inactive() is supposed to clean up the attribute fork when
the inode is being freed. While it removes attribute fork extents,
it completely ignores attributes in local format, which means that
there can still be active attributes on the inode after
xfs_attr_inactive() has run.
This leads to problems with concurrent inode writeback - the in-core
inode attribute fork is removed without locking on the assumption
that nothing will be attempting to access the attribute fork after a
call to xfs_attr_inactive() because it isn't supposed to exist on
disk any more.
To fix this, make xfs_attr_inactive() completely remove all traces
of the attribute fork from the inode, regardless of it's state.
Further, also remove the in-core attribute fork structure safely so
that there is nothing further that needs to be done by callers to
clean up the attribute fork. This means we can remove the in-core
and on-disk attribute forks atomically.
Also, on error simply remove the in-memory attribute fork. There's
nothing that can be done with it once we have failed to remove the
on-disk attribute fork, so we may as well just blow it away here
anyway.
cc: <stable@vger.kernel.org> # 3.12 to 4.0
Reported-by: Waiman Long <waiman.long@hp.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
This results in BMBT corruption, as seen by this test:
# mkfs.xfs -f -d size=40051712b,agcount=4 /dev/vdc
....
# mount /dev/vdc /mnt/scratch
# xfs_io -ft -c "extsize 16m" -c "falloc 0 30g" -c "bmap -vp" /mnt/scratch/foo
which results in this failure on a debug kernel:
XFS: Assertion failed: (blockcount & xfs_mask64hi(64-BMBT_BLOCKCOUNT_BITLEN)) == 0, file: fs/xfs/libxfs/xfs_bmap_btree.c, line: 211
....
Call Trace:
[<ffffffff814cf0ff>] xfs_bmbt_set_allf+0x8f/0x100
[<ffffffff814cf18d>] xfs_bmbt_set_all+0x1d/0x20
[<ffffffff814f2efe>] xfs_iext_insert+0x9e/0x120
[<ffffffff814c7956>] ? xfs_bmap_add_extent_hole_real+0x1c6/0xc70
[<ffffffff814c7956>] xfs_bmap_add_extent_hole_real+0x1c6/0xc70
[<ffffffff814caaab>] xfs_bmapi_write+0x72b/0xed0
[<ffffffff811c72ac>] ? kmem_cache_alloc+0x15c/0x170
[<ffffffff814fe070>] xfs_alloc_file_space+0x160/0x400
[<ffffffff81ddcc29>] ? down_write+0x29/0x60
[<ffffffff815063eb>] xfs_file_fallocate+0x29b/0x310
[<ffffffff811d2bc8>] ? __sb_start_write+0x58/0x120
[<ffffffff811e3e18>] ? do_vfs_ioctl+0x318/0x570
[<ffffffff811cd680>] vfs_fallocate+0x140/0x260
[<ffffffff811ce6f8>] SyS_fallocate+0x48/0x80
[<ffffffff81ddec09>] system_call_fastpath+0x12/0x17
The tracepoint that indicates the extent that triggered the assert
failure is:
xfs_iext_insert: idx 0 offset 0 block 16777224 count 2097152 flag 1
Clearly indicating that the extent length is greater than MAXEXTLEN,
which is 2097151. A prior trace point shows the allocation was an
exact size match and that a length greater than MAXEXTLEN was asked
for:
xfs_alloc_size_done: agno 1 agbno 8 minlen 2097152 maxlen 2097152
^^^^^^^ ^^^^^^^
We don't see this problem with extent size hints through the IO path
because we can't do single IOs large enough to trigger MAXEXTLEN
allocation. fallocate(), OTOH, is not limited in it's allocation
sizes and so needs help here.
The issue is that the extent size hint alignment is rounding up the
extent size past MAXEXTLEN, because xfs_bmapi_write() is not taking
into account extent size hints when calculating the maximum extent
length to allocate. xfs_bmapi_reserve_delalloc() is already doing
this, but direct extent allocation is not.
Unfortunately, the calculation in xfs_bmapi_reserve_delalloc() is
wrong, and it works only because delayed allocation extents are not
limited in size to MAXEXTLEN in the in-core extent tree. hence this
calculation does not work for direct allocation, and the delalloc
code needs fixing. This may, in fact be the underlying bug that
occassionally causes transaction overruns in delayed allocation
extent conversion, so now we know it's wrong we should fix it, too.
Many thanks to Brian Foster for finding this problem during review
of this patch.
Hence the fix, after much code reading, is to allow
xfs_bmap_extsize_align() to align partial extents when full
alignment would extend the alignment past MAXEXTLEN. We can safely
do this because all callers have higher layer allocation loops that
already handle short allocations, and so will simply run another
allocation to cover the remainder of the requested allocation range
that we ignored during alignment. The advantage of this approach is
that it also removes the need for callers to do anything other than
limit their requests to MAXEXTLEN - they don't really need to be
aware of extent size hints at all.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Because the counters use a custom batch size, the comparison
functions need to be aware of that batch size otherwise the
comparison does not work correctly. This leads to ASSERT failures
on generic/027 like this:
XFS: Assertion failed: 0, file: fs/xfs/xfs_mount.c, line: 1099
------------[ cut here ]------------
....
Call Trace:
[<ffffffff81522a39>] xfs_mod_icount+0x99/0xc0
[<ffffffff815285cb>] xfs_trans_unreserve_and_mod_sb+0x28b/0x5b0
[<ffffffff8152f941>] xfs_log_commit_cil+0x321/0x580
[<ffffffff81528e17>] xfs_trans_commit+0xb7/0x260
[<ffffffff81503d4d>] xfs_bmap_finish+0xcd/0x1b0
[<ffffffff8151da41>] xfs_inactive_ifree+0x1e1/0x250
[<ffffffff8151dbe0>] xfs_inactive+0x130/0x200
[<ffffffff81523a21>] xfs_fs_evict_inode+0x91/0xf0
[<ffffffff811f3958>] evict+0xb8/0x190
[<ffffffff811f433b>] iput+0x18b/0x1f0
[<ffffffff811e8853>] do_unlinkat+0x1f3/0x320
[<ffffffff811d548a>] ? filp_close+0x5a/0x80
[<ffffffff811e999b>] SyS_unlinkat+0x1b/0x40
[<ffffffff81e0892e>] system_call_fastpath+0x12/0x71
This is a regression introduced by commit 501ab32 ("xfs: use generic
percpu counters for inode counter").
This patch fixes the same problem for both the inode counter and the
free block counter in the superblocks.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Function percpu_counter_read just return the current counter, which can be
negative. This will cause the checking of "allocated inode
counts <= m_maxicount" false positive. Use percpu_counter_read_positive can
solve this problem, and be consistent with the purpose to introduce percpu
mechanism to xfs.
Signed-off-by: George Wang <xuw2015@gmail.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
a) instead of storing the symlink body (via nd_set_link()) and returning
an opaque pointer later passed to ->put_link(), ->follow_link() _stores_
that opaque pointer (into void * passed by address by caller) and returns
the symlink body. Returning ERR_PTR() on error, NULL on jump (procfs magic
symlinks) and pointer to symlink body for normal symlinks. Stored pointer
is ignored in all cases except the last one.
Storing NULL for opaque pointer (or not storing it at all) means no call
of ->put_link().
b) the body used to be passed to ->put_link() implicitly (via nameidata).
Now only the opaque pointer is. In the cases when we used the symlink body
to free stuff, ->follow_link() now should store it as opaque pointer in addition
to returning it.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Struct bio has a reference count that controls when it can be freed.
Most uses cases is allocating the bio, which then returns with a
single reference to it, doing IO, and then dropping that single
reference. We can remove this atomic_dec_and_test() in the completion
path, if nobody else is holding a reference to the bio.
If someone does call bio_get() on the bio, then we flag the bio as
now having valid count and that we must properly honor the reference
count when it's being put.
Tested-by: Robert Elliott <elliott@hp.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Pull fourth vfs update from Al Viro:
"d_inode() annotations from David Howells (sat in for-next since before
the beginning of merge window) + four assorted fixes"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
RCU pathwalk breakage when running into a symlink overmounting something
fix I_DIO_WAKEUP definition
direct-io: only inc/dec inode->i_dio_count for file systems
fs/9p: fix readdir()
VFS: assorted d_backing_inode() annotations
VFS: fs/inode.c helpers: d_inode() annotations
VFS: fs/cachefiles: d_backing_inode() annotations
VFS: fs library helpers: d_inode() annotations
VFS: assorted weird filesystems: d_inode() annotations
VFS: normal filesystems (and lustre): d_inode() annotations
VFS: security/: d_inode() annotations
VFS: security/: d_backing_inode() annotations
VFS: net/: d_inode() annotations
VFS: net/unix: d_backing_inode() annotations
VFS: kernel/: d_inode() annotations
VFS: audit: d_backing_inode() annotations
VFS: Fix up some ->d_inode accesses in the chelsio driver
VFS: Cachefiles should perform fs modifications on the top layer only
VFS: AF_UNIX sockets should call mknod on the top layer only
This update contains:
o RENAME_WHITEOUT support
o conversion of per-cpu superblock accounting to use generic counters
o new inode mmap lock so that we can lock page faults out of truncate, hole
punch and other direct extent manipulation functions to avoid racing mmap
writes from causing data corruption
o rework of direct IO submission and completion to solve data corruption issue
when running concurrent extending DIO writes. Also solves problem of running
IO completion transactions in interrupt context during size extending AIO
writes.
o FALLOC_FL_INSERT_RANGE support for inserting holes into a file via direct
extent manipulation to avoid needing to copy data within the file
o attribute block header field overflow fix for 64k block size filesystems
o Lots of changes to log messaging to be more informative and concise when
errors occur. Also prevent a lot of unnecessary log spamming due to cascading
failures in error conditions.
o lots of cleanups and bug fixes
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Merge tag 'xfs-for-linus-4.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs
Pull xfs update from Dave Chinner:
"This update contains:
- RENAME_WHITEOUT support
- conversion of per-cpu superblock accounting to use generic counters
- new inode mmap lock so that we can lock page faults out of
truncate, hole punch and other direct extent manipulation functions
to avoid racing mmap writes from causing data corruption
- rework of direct IO submission and completion to solve data
corruption issue when running concurrent extending DIO writes.
Also solves problem of running IO completion transactions in
interrupt context during size extending AIO writes.
- FALLOC_FL_INSERT_RANGE support for inserting holes into a file via
direct extent manipulation to avoid needing to copy data within the
file
- attribute block header field overflow fix for 64k block size
filesystems
- Lots of changes to log messaging to be more informative and concise
when errors occur. Also prevent a lot of unnecessary log spamming
due to cascading failures in error conditions.
- lots of cleanups and bug fixes
One thing of note is the direct IO fixes that we merged last week
after the window opened. Even though a little late, they fix a user
reported data corruption and have been pretty well tested. I figured
there was not much point waiting another 2 weeks for -rc1 to be
released just so I could send them to you..."
* tag 'xfs-for-linus-4.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs: (49 commits)
xfs: using generic_file_direct_write() is unnecessary
xfs: direct IO EOF zeroing needs to drain AIO
xfs: DIO write completion size updates race
xfs: DIO writes within EOF don't need an ioend
xfs: handle DIO overwrite EOF update completion correctly
xfs: DIO needs an ioend for writes
xfs: move DIO mapping size calculation
xfs: factor DIO write mapping from get_blocks
xfs: unlock i_mutex in xfs_break_layouts
xfs: kill unnecessary firstused overflow check on attr3 leaf removal
xfs: use larger in-core attr firstused field and detect overflow
xfs: pass attr geometry to attr leaf header conversion functions
xfs: disallow ro->rw remount on norecovery mount
xfs: xfs_shift_file_space can be static
xfs: Add support FALLOC_FL_INSERT_RANGE for fallocate
fs: Add support FALLOC_FL_INSERT_RANGE for fallocate
xfs: Fix incorrect positive ENOMEM return
xfs: xfs_mru_cache_insert() should use GFP_NOFS
xfs: %pF is only for function pointers
xfs: fix shadow warning in xfs_da3_root_split()
...
Pull third hunk of vfs changes from Al Viro:
"This contains the ->direct_IO() changes from Omar + saner
generic_write_checks() + dealing with fcntl()/{read,write}() races
(mirroring O_APPEND/O_DIRECT into iocb->ki_flags and instead of
repeatedly looking at ->f_flags, which can be changed by fcntl(2),
check ->ki_flags - which cannot) + infrastructure bits for dhowells'
d_inode annotations + Christophs switch of /dev/loop to
vfs_iter_write()"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (30 commits)
block: loop: switch to VFS ITER_BVEC
configfs: Fix inconsistent use of file_inode() vs file->f_path.dentry->d_inode
VFS: Make pathwalk use d_is_reg() rather than S_ISREG()
VFS: Fix up debugfs to use d_is_dir() in place of S_ISDIR()
VFS: Combine inode checks with d_is_negative() and d_is_positive() in pathwalk
NFS: Don't use d_inode as a variable name
VFS: Impose ordering on accesses of d_inode and d_flags
VFS: Add owner-filesystem positive/negative dentry checks
nfs: generic_write_checks() shouldn't be done on swapout...
ocfs2: use __generic_file_write_iter()
mirror O_APPEND and O_DIRECT into iocb->ki_flags
switch generic_write_checks() to iocb and iter
ocfs2: move generic_write_checks() before the alignment checks
ocfs2_file_write_iter: stop messing with ppos
udf_file_write_iter: reorder and simplify
fuse: ->direct_IO() doesn't need generic_write_checks()
ext4_file_write_iter: move generic_write_checks() up
xfs_file_aio_write_checks: switch to iocb/iov_iter
generic_write_checks(): drop isblk argument
blkdev_write_iter: expand generic_file_checks() call in there
...
Pull quota and udf updates from Jan Kara:
"The pull contains quota changes which complete unification of XFS and
VFS quota interfaces (so tools can use either interface to manipulate
any filesystem). There's also a patch to support project quotas in
VFS quota subsystem from Li Xi.
Finally there's a bunch of UDF fixes and cleanups and tiny cleanup in
reiserfs & ext3"
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: (21 commits)
udf: Update ctime and mtime when directory is modified
udf: return correct errno for udf_update_inode()
ext3: Remove useless condition in if statement.
vfs: Add general support to enforce project quota limits
reiserfs: fix __RASSERT format string
udf: use int for allocated blocks instead of sector_t
udf: remove redundant buffer_head.h includes
udf: remove else after return in __load_block_bitmap()
udf: remove unused variable in udf_table_free_blocks()
quota: Fix maximum quota limit settings
quota: reorder flags in quota state
quota: paranoia: check quota tree root
quota: optimize i_dquot access
quota: Hook up Q_XSETQLIM for id 0 to ->set_info
xfs: Add support for Q_SETINFO
quota: Make ->set_info use structure with neccesary info to VFS and XFS
quota: Remove ->get_xstate and ->get_xstatev callbacks
gfs2: Convert to using ->get_state callback
xfs: Convert to using ->get_state callback
quota: Wire up Q_GETXSTATE and Q_GETXSTATV calls to work with ->get_state
...
generic_file_direct_write() does all sorts of things to make DIO
work "sorta ok" with mixed buffered IO workloads. We already do
most of this work in xfs_file_aio_dio_write() because of the locking
requirements, so there's only a couple of things it does for us.
The first thing is that it does a page cache invalidation after the
->direct_IO callout. This can easily be added to the XFS code.
The second thing it does is that if data was written, it updates the
iov_iter structure to reflect the data written, and then does EOF
size updates if necessary. For XFS, these EOF size updates are now
not necessary, as we do them safely and race-free in IO completion
context. That leaves just the iov_iter update, and that's also moved
to the XFS code.
Therefore we don't need to call generic_file_direct_write() and in
doing so remove redundant buffered writeback and page cache
invalidation calls from the DIO submission path. We also remove a
racy EOF size update, and make the DIO submission code in XFS much
easier to follow. Wins all round, really.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
When we are doing AIO DIO writes, the IOLOCK only provides an IO
submission barrier. When we need to do EOF zeroing, we need to ensure
that no other IO is in progress and all pending in-core EOF updates
have been completed. This requires us to wait for all outstanding
AIO DIO writes to the inode to complete and, if necessary, run their
EOF updates.
Once all the EOF updates are complete, we can then restart
xfs_file_aio_write_checks() while holding the IOLOCK_EXCL, knowing
that EOF is up to date and we have exclusive IO access to the file
so we can run EOF block zeroing if we need to without interference.
This gives EOF zeroing the same exclusivity against other IO as we
provide truncate operations.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
xfs_end_io_direct_write() can race with other IO completions when
updating the in-core inode size. The IO completion processing is not
serialised for direct IO - they are done either under the
IOLOCK_SHARED for non-AIO DIO, and without any IOLOCK held at all
during AIO DIO completion. Hence the non-atomic test-and-set update
of the in-core inode size is racy and can result in the in-core
inode size going backwards if the race if hit just right.
If the inode size goes backwards, this can trigger the EOF zeroing
code to run incorrectly on the next IO, which then will zero data
that has successfully been written to disk by a previous DIO.
To fix this bug, we need to serialise the test/set updates of the
in-core inode size. This first patch introduces locking around the
relevant updates and checks in the DIO path. Because we now have an
ioend in xfs_end_io_direct_write(), we know exactly then we are
doing an IO that requires an in-core EOF update, and we know that
they are not running in interrupt context. As such, we do not need to
use irqsave() spinlock variants to protect against interrupts while
the lock is held.
Hence we can use an existing spinlock in the inode to do this
serialisation and so not need to grow the struct xfs_inode just to
work around this problem.
This patch does not address the test/set EOF update in
generic_file_write_direct() for various reasons - that will be done
as a followup with separate explanation.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
DIO writes that lie entirely within EOF have nothing to do in IO
completion. In this case, we don't need no steekin' ioend, and so we
can avoid allocating an ioend until we have a mapping that spans
EOF.
This means that IO completion has two contexts - deferred completion
to the dio workqueue that uses an ioend, and interrupt completion
that does nothing because there is nothing that can be done in this
context.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Currently a DIO overwrite that extends the EOF (e.g sub-block IO or
write into allocated blocks beyond EOF) requires a transaction for
the EOF update. Thi is done in IO completion context, but we aren't
explicitly handling this situation properly and so it can run in
interrupt context. Ensure that we defer IO that spans EOF correctly
to the DIO completion workqueue, and now that we have an ioend in IO
completion we can use the common ioend completion path to do all the
work.
Note: we do not preallocate the append transaction as we can have
multiple mapping and allocation calls per direct IO. hence
preallocating can still leave us with nested transactions by
attempting to map and allocate more blocks after we've preallocated
an append transaction.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Currently we can only tell DIO completion that an IO requires
unwritten extent completion. This is done by a hacky non-null
private pointer passed to Io completion, but the private pointer
does not actually contain any information that is used.
We also need to pass to IO completion the fact that the IO may be
beyond EOF and so a size update transaction needs to be done. This
is currently determined by checks in the io completion, but we need
to determine if this is necessary at block mapping time as we need
to defer the size update transactions to a completion workqueue,
just like unwritten extent conversion.
To do this, first we need to allocate and pass an ioend to to IO
completion. Add this for unwritten extent conversion; we'll do the
EOF updates in the next commit.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The mapping size calculation is done last in __xfs_get_blocks(), but
we are going to need the actual mapping size we will use to map the
direct IO correctly in xfs_map_direct(). Factor out the calculation
for code clarity, and move the call to be the first operation in
mapping the extent to the returned buffer.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Clarify and separate the buffer mapping logic so that the direct IO mapping is
not tangled up in propagating the extent status to teh mapping buffer. This
makes it easier to extend the direct IO mapping to use an ioend in future.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
that's the bulk of filesystem drivers dealing with inodes of their own
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
We want to drop all I/O path locks when recalling layouts, and that includes
i_mutex for the write path. Without this we get stuck processe when recalls
take too long.
[dchinner: fix build with !CONFIG_PNFS]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
xfs_attr3_leaf_remove() removes an attribute from an attr leaf block. If
the attribute nameval data happens to be at the start of the nameval
region, a new start offset (firstused) for the region is calculated
(since the region grows from the tail of the block to the start). Once
the new firstused is calculated, it is checked for zero in an apparent
overflow check.
Now that the in-core firstused is 32-bit, overflow is not possible and
this check can be removed. Since the purpose for this check is not
documented and appears to exist since the port to Linux, be conservative
and replace it with an assert.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The on-disk xfs_attr3_leaf_hdr structure firstused field is 16-bit and
subject to overflow when fs block size is 64k. The field is typically
initialized to block size when an attr leaf block is initialized. This
problem is demonstrated by assert failures when running xfstests
generic/117 on an fs with 64k blocks.
To support the existing attr leaf block algorithms for insertion,
rebalance and entry movement, increase the size of the in-core firstused
field to 32-bit and handle the potential overflow on conversion to/from
the on-disk structure. If the overflow condition occurs, set a special
value in the firstused field that is translated back on header read. The
special value is only required in the case of an empty 64k attr block. A
value of zero is used because firstused is initialized to the block size
and grows backwards from there. Furthermore, the attribute block header
occupies the first bytes of the block. Thus, a value of zero has no
other legitimate meaning for this structure. Two new conversion helpers
are created to manage the conversion of firstused to and from disk.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The firstused field of the xfs_attr3_leaf_hdr structure is subject to an
overflow when fs blocksize is 64k. In preparation to handle this
overflow in the header conversion functions, pass the attribute geometry
to the functions that convert the in-core structure to and from the
on-disk structure.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
There's a bit of a loophole in norecovery mount handling right
now: an initial mount must be readonly, but nothing prevents
a mount -o remount,rw from producing a writable, unrecovered
xfs filesystem.
It might be possible to try to perform a log recovery when this
is requested, but I'm not sure it's worth the effort. For now,
simply disallow this sort of transition.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
... returning -E... upon error and amount of data left in iter after
(possible) truncation upon success. Note, that normal case gives
a non-zero (positive) return value, so any tests for != 0 _must_ be
updated.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Conflicts:
fs/ext4/file.c
The rw parameter to direct_IO is redundant with iov_iter->type, and
treated slightly differently just about everywhere it's used: some users
do rw & WRITE, and others do rw == WRITE where they should be doing a
bitwise check. Simplify this with the new iov_iter_rw() helper, which
always returns either READ or WRITE.
Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Most filesystems call through to these at some point, so we'll start
here.
Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
