Add some helpers to assemble a list of fs block extents. Generally,
repair functions will iterate the rmapbt to make a list (1) of all
extents owned by the nominal owner of the metadata structure; then they
will iterate all other structures with the same rmap owner to make a
list (2) of active blocks; and finally we have a subtraction function to
subtract all the blocks in (2) from (1), with the result that (1) is now
a list of blocks that were owned by the old btree and must be disposed.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Add a pair of helper functions to allocate and initialize fresh btree
roots. The repair functions will use these as part of recreating
corrupted metadata.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
For repairs, we need to reserve at least as many blocks as we think
we're going to need to rebuild the data structure, and we're going to
need some helpers to roll transactions while maintaining locks on the AG
headers so that other threads cannot wander into the middle of a repair.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Grab and hold the per-AG data across a scrub run whenever relevant.
This helps us avoid repeated trips through rcu and the radix tree
in the repair code.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Use new return type vm_fault_t for fault handlers.
Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
In commit a6a781a58b ("xfs: have buffer verifier functions
report failing address") the bad magic number return was ported
incorrectly.
Fixes: a6a781a58b
Reported-by: syzbot+08ab33be0178b76851c8@syzkaller.appspotmail.com
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
The GET ioctl is trivial, just return the current label.
The SET ioctl is more involved:
It transactionally modifies the superblock to write a new filesystem
label to the primary super.
A new variant of xfs_sync_sb then writes the superblock buffer
immediately to disk so that the change is visible from userspace.
It then invalidates any page cache that userspace might have previously
read on the block device so that i.e. blkid can see the change
immediately, and updates all secondary superblocks as userspace relable
does.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
[darrick: use dchinner's new xfs_update_secondary_sbs function]
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Growfs currently manually codes the extension of the last AG in a
filesytem during the growfs process. Factor that out of the growfs
code and move it into libxfs along with teh rest of the AG header
modification code.
Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
So it can be shared with userspace (e.g. mkfs) easily.
Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Right now we wait until we've committed changes to the primary
superblock before we initialise any of the new secondary
superblocks. This means that if we have any write errors for new
secondary superblocks we end up with garbage in place rather than
zeros or even an "in progress" superblock to indicate a grow
operation is being done.
To ensure we can write the secondary superblocks, initialise them
earlier in the same loop that initialises the AG headers. We stamp
the new secondary superblocks here with the old geometry, but set
the "sb_inprogress" field to indicate that updates are being done to
the superblock so they cannot be used. This will result in the
secondary superblock fields being updated or triggering errors that
will abort the grow before we commit any permanent changes.
This also means we can change the update mechanism of the secondary
superblocks. We know that we are going to wholly overwrite the
information in the struct xfs_sb in the buffer, so there's no point
reading it from disk. Just allocate an uncached buffer, zero it in
memory, stamp the new superblock structure in it and write it out.
If we fail to write it out, then we'll leave the existing sb (old or
new w/ inprogress) on disk for repair to deal with later.
Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
This happens after all the transactions to update the superblock
occur, and errors need to be handled slightly differently. Seperate
out the code into it's own function, and clean up the error goto
stack in the core growfs code as it is now much simpler.
Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
When growfs changes the imaxpct value of the filesystem, it runs
through all the "change size" growfs code, whether it needs to or
not. Separate out changing imaxpct into it's own function and
transaction to simplify the rest of the growfs code.
Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
There's still more cookie cutter code in setting up each AG header.
Separate all the variables into a simple structure and iterate a
table of header definitions to initialise everything.
Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Cookie cutter code, easily factored.
Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
We currently write all new AG headers synchronously, which can be
slow for large grow operations. All we really need to do is ensure
all the headers are on disk before we run the growfs transaction, so
convert this to a buffer list and a delayed write operation. We
block waiting for the delayed write buffer submission to complete,
so this will fulfill the requirement to have all the buffers written
correctly before proceeding.
Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
The intialisation of new AG headers is mostly common with the
userspace mkfs code and growfs in the kernel, so start factoring it
out so we can move it to libxfs and use it in both places.
Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
For the new growfs work, we want to ensure that we serialise
secondary superblock updates with other operations (e.g. scrub)
correctly, but we don't want to cache the buffers for long term
reuse. We need cached buffers for serialisation, however.
To solve this, introduce a "oneshot" buffer which will be marshalled
through the cache but then released once the last current reference
goes away. If the buffer is already cached, then we ignore the
"one-shot" behaviour and leave the buffer in the state it was prior
to the one-shot command being run. This means we don't perturb
either the working set or existing cached buffer state by a one-shot
operation.
Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Plumb in the pieces necessary to make the "scrub" subfunction of
the scrub ioctl actually work. This means that we make the IFLAG_REPAIR
flag to the scrub ioctl actually do something, and we add an errortag
knob so that xfstests can force the kernel to rebuild a metadata
structure even if there's nothing wrong with it.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
These tracepoints will be used to debug the online repair routines.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Teach xfs_bmapi_remap how to map in unwritten extent and to skip rmap
updates. This enables us to rebuild real and unwritten extents from the
rmapbt.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Add a new flags argument to xfs_bmapi_remapi so that we can pass BMAPI
flags into the function. This enables us to pass in BMAPI_ATTRFORK so
that we can remap things into the attribute fork. Eventually the
online repair code will use this to rebuild attribute forks, so make it
non-static.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
This function is basically a generic AGFL block iterator, so promote it
to libxfs ahead of online repair wanting to use it.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
In normal operation, the XFS convention is to take an inode's iolock
and then allocate a transaction. However, when scrubbing parent inodes
this is inverted -- we allocated the transaction to do the scrub, and
now we're trying to grab the parent's iolock. This can lead to ABBA
deadlocks: some thread grabbed the parent's iolock and is waiting for
space for a transaction while our parent scrubber is sitting on a
transaction trying to get the parent's iolock.
Therefore, convert all iolock attempts to use trylock; if that fails,
they can use the existing mechanisms to back off and try again.
The ABBA deadlock didn't happen with a non-repair scrub because the
transactions don't reserve any space, but repair scrubs require
reservation in order to update metadata. However, any other concurrent
metadata update (e.g. directory create in the parent) could also induce
this deadlock with the parent scrubber.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
The realtime bitmap and summary inodes live on the metadata device, so
we can scrub their data forks with the regular scrubbers.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Replace the quota scrubber's open-coded data fork scrubber with a
redirected call to the bmapbtd scrubber. This strengthens the quota
scrub to include all the cross-referencing that it does.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
If we've already decided that something is corrupt, we might as well
abort all the loops and exit as quickly as possible.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Replace all the if (!error) weirdness with helper functions that follow
our regular coding practices, and factor out the ternary expression soup.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Secondary superblocks are rarely used, so create a helper to read a
given non-primary AG's superblock and ensure that it won't stick around
hogging memory.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Don't bother looking for cross-referencing problems if the metadata is
already corrupt or we've already found a cross-referencing problem.
Since we added a helper function for flags testing, convert existing
users to use it.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
We recently had an oops reported on a 4.14 kernel in
xfs_reclaim_inodes_count() where sb->s_fs_info pointed to garbage
and so the m_perag_tree lookup walked into lala land.
Essentially, the machine was under memory pressure when the mount
was being run, xfs_fs_fill_super() failed after allocating the
xfs_mount and attaching it to sb->s_fs_info. It then cleaned up and
freed the xfs_mount, but the sb->s_fs_info field still pointed to
the freed memory. Hence when the superblock shrinker then ran
it fell off the bad pointer.
With the superblock shrinker problem fixed at teh VFS level, this
stale s_fs_info pointer is still a problem - we use it
unconditionally in ->put_super when the superblock is being torn
down, and hence we can still trip over it after a ->fill_super
call failure. Hence we need to clear s_fs_info if
xfs-fs_fill_super() fails, and we need to check if it's valid in
the places it can potentially be dereferenced after a ->fill_super
failure.
Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
The changes to skip discards of speculative preallocation and
unwritten extents introduced several new wrapper functions through
the bunmapi -> extent free codepath to reduce churn in all of the
associated callers. In several cases, these wrappers simply toggle a
single flag to skip or not skip discards for the resulting blocks.
The explicit _nodiscard() wrappers for such an isolated set of
callers is a bit overkill. Kill off these wrappers and replace with
the calls to the underlying functions in the contexts that need to
control discard behavior. Retain the wrappers that preserve the
original calling conventions to serve the original purpose of
reducing code churn.
This is a refactoring patch and does not change behavior.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Add a new iomap_swapfile_activate function so that filesystems can
activate swap files without having to use the obsolete and slow bmap
function. This enables XFS to support fallocate'd swap files and
swap files on realtime devices.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Rebuilding the reverse-mapping tree requires us to quiesce all inodes in
the filesystem, so we must stop background reclamation of post-EOF and
CoW prealloc blocks.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Add a new flag, XFS_BMAPI_NORMAP, which will perform file block
remapping without updating the rmapbt. This will be used by the repair
code to reconstruct bmbts from the rmapbt, in which case we don't want
the rmapbt update.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Add a couple of functions to the refcount btree and generic btree code
that will be used to repair the refcountbt.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Add a couple of functions to the reverse mapping btree that will be used
to repair the rmapbt.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Expose various helpers that the repair code will want to use.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Add a bunch of helper functions that calculate the sizes of various
btrees. These will be used to repair btrees and btree headers.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Since the transaction allocation helper is about to become more complex,
move it to common.c and remove the redundant parameters.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Strengthen the btree block header checks to detect the number of records
being less than the btree type's minimum record count. Certain blocks
are allowed to violate this constraint -- specifically any btree block
at the top of the tree can have fewer than minrecs records.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
All scrub code runs in transaction context, which means that memory
allocations are automatically run in PF_MEMALLOC_NOFS context. It's
therefore unnecessary to pass in KM_NOFS to allocation routines, so
clean them all out.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Refactor the quota scrubber to take the quotaofflock and grab the quota
inode in the setup function so that we can treat quota in the same
"scrub in the context of this inode" (i.e. sc->ip) manner as we treat
any other inode. We do have to drop the quota inode's ILOCK_EXCL to use
dqiterate, but since dquots have their own individual locks the ILOCK
wasn't helping us anyway.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Create a helper function to iterate all the dquots of a given type in
the system, and refactor the dquot scrub to use it. This will get more
use in the quota repair code.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
The function 'xfs_qm_dqiterate' doesn't iterate dquots at all, it
iterates all dquot blocks of a quota inode and clears the counters.
Therefore, change the name to something more descriptive so that we can
introduce a real dquot iterator later.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
DQALLOC is only ever used with xfs_qm_dqget*, and the only flag that the
_dqget family of functions cares about is DQALLOC. Therefore, change
it to a boolean 'can alloc?' flag for the dqget interfaces where that
makes sense.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
The quota initialization code needs an "uncached" variant of _dqget to
read in default quota limits and timers before the dquot cache is fully
set up. We've already split up _dqget into its component pieces so
create a fourth variant to address this need, and make dqread internal
to xfs_dquot.c again.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Separate the disk dquot read and allocation functionality into
two helper functions, then refactor dqread to call them directly.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Create two incore dquot initialization functions that will help us to
disentangle dqget and dqread.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Quotacheck only runs during mount, which means that there are no other
processes in the system that could be doing chown or chproj. Therefore
there's no potential for racing to attach dquots to the inode so we can
drop all the ILOCK and race detection bits from quotacheck.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>