Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
The create transaction reservation calculation has two different
branches of code depending on whether the filesystem is a v5 format
fs or older. Each branch considers the max reservation between the
allocation case (new chunk allocation + record insert) and the
modify case (chunk exists, record modification) of inode allocation.
The modify case is the same for both superblock versions with the
exception of the finobt. The finobt helper checks the feature bit,
however, and so the modify case already shares the same code.
Now that inode chunk allocation has been refactored into a helper
that checks the superblock version to calculate the appropriate
reservation for the create transaction, the only remaining
difference between the create and icreate branches is the call to
the finobt helper. As noted above, the finobt helper is a no-op when
the feature is not enabled. Therefore, these branches are
effectively duplicate and can be condensed.
Remove the xfs_calc_create_*() branch of functions and update the
various callers to use the xfs_calc_icreate_*() variant. The latter
creates the same reservation size for v4 create transactions as the
removed branch. As such, this patch does not result in transaction
reservation changes.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
The reservation for the various forms of inode allocation is
scattered across several different functions. This includes two
variants of chunk allocation (v5 icreate transactions vs. older
create transactions) and the inode free transaction.
To clean up some of this code and clarify the purpose of specific
allocfree reservations, continue the pattern of defining helper
functions for smaller operational units of broader transactions.
Refactor the reservation into an inode chunk alloc/free helper that
considers the various conditions based on filesystem format.
An inode chunk free involves an extent free and buffer
invalidations. The latter requires reservation for log headers only.
An inode chunk allocation modifies the free space btrees and logs
the chunk on v4 supers. v5 supers initialize the inode chunk using
ordered buffers and so do not log the chunk.
As a side effect of this refactoring, add one more allocfree res to
the ifree transaction. Technically this does not serve a specific
purpose because inode chunks are freed via deferred operations and
thus occur after a transaction roll. tr_ifree has a bit of a history
of tx overruns caused by too many agfl fixups during sustained file
deletion workloads, so add this extra reservation as a form of
padding nonetheless.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Analysis of recent reports of log reservation overruns and code
inspection has uncovered that the reservations associated with inode
operations may not cover the worst case scenarios. In particular,
many cases only include one allocfree res. for a particular
operation even though said operations may also entail AGFL fixups
and inode btree block allocations in addition to the actual inode
chunk allocation. This can easily turn into two or three block
allocations (or frees) per operation.
In theory, the only way to define the worst case reservation is to
include an allocfree res for each individual allocation in a
transaction. Since that is impractical (we can perform multiple agfl
fixups per tx and not every allocation results in a full tree
operation), we need to find a reasonable compromise that addresses
the deficiency in practice without blowing out the size of the
transactions.
Since the inode btrees are not filled by the AGFL, record insertion
and removal can directly result in block allocations and frees
depending on the shape of the tree. These allocations and frees
occur in the same transaction context as the inobt update itself,
but are separate from the allocation/free that might be required for
an inode chunk. Therefore, it makes sense to assume that an [f]inobt
insert/remove can directly result in one or more block allocations
on behalf of the tree.
Refactor the inode transaction reservations to include one allocfree
res. per inode btree modification to cover allocations required by
the tree itself. This separates the reservation required to allocate
the inode chunk from the reservation required for inobt record
insertion/removal. Apply the same logic to the finobt. This results
in killing off the finobt modify condition because we no longer
assume that the broader transaction reservation will cover finobt
block allocations and finobt shape changes can occur in either of
the inobt allocation or modify situations.
Suggested-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
The truncate transaction does not ever modify the inode btree, but
includes an associated log reservation. Update
xfs_calc_itruncate_reservation() to remove the reservation
associated with inobt updates.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
The current AGI unlinked list addition and removal reservations do
not reflect the worst case log usage. An unlinked list removal can
log up to two on-disk inode clusters but only includes reservation
for one. An unlinked list addition logs the on-disk cluster but
includes reservation for an in-core inode.
Update the AGI unlinked list reservation helpers to calculate the
correct worst case reservation for the associated operations.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
The tr_ifree transaction handles inode unlinks and inode chunk
frees. The current transaction calculation does not accurately
reflect worst case changes to the inode btree, however. The inobt
portion of the current transaction reservation only covers
modification of a single inobt buffer (for the particular inode
record). This is a historical artifact from the days before XFS
supported full inode chunk removal.
When support for inode chunk removal was added in commit
254f6311ed1b ("Implement deletion of inode clusters in XFS."), the
additional log reservation required for chunk removal was not added
correctly. The new reservation only considered the header overhead
of associated buffers rather than the full contents of the btrees
and AGF and AGFL buffers affected by the transaction. The
reservation for the free space btrees was subsequently fixed up in
commit 5fe6abb82f76 ("Add space for inode and allocation btrees to
ITRUNCATE log reservation"), but the res. for full inobt joins has
never been added.
Further review of the ifree reservation uncovered a couple more
problems:
- The undocumented +2 blocks are intended for the AGF and AGFL, but
are also not sized correctly and should be logged as full sectors
(not FSBs).
- The additional single block header is undocumented and serves no
apparent purpose.
Update xfs_calc_ifree_reservation() to include a full inobt join in
the reservation calculation. Refactor the undocumented blocks
appropriately and fix up the comments to reflect the current
calculation.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
XFS has a maximum symlink target length of 1024 bytes; this is a
holdover from the Irix days. Unfortunately, the constant establishing
this is 'MAXPATHLEN' and is /not/ the same as the Linux MAXPATHLEN,
which is 4096.
The kernel enforces its 1024 byte MAXPATHLEN on symlink targets, but
xfsprogs picks up the (Linux) system 4096 byte MAXPATHLEN, which means
that xfs_repair doesn't complain about oversized symlinks.
Since this is an on-disk format constraint, put the define in the XFS
namespace and move everything over to use the new name.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Increase the log reservations to handle the increased rolling that
happens at the end of copy-on-write operations.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Every time we allocate or free a data extent, we might need to split
the refcount btree. Reserve some blocks in the transaction to handle
this possibility. Even though the deferred refcount code can roll a
transaction to avoid overloading the transaction, we can still exceed
the reservation.
Certain pathological workloads (1k blocks, no cowextsize hint, random
directio writes), cause a perfect storm wherein a refcount adjustment
of a large range of blocks causes full tree splits in two separate
extents in two separate refcount tree blocks; allocating new refcount
tree blocks causes rmap btree splits; and all the allocation activity
causes the freespace btrees to split, blowing the reservation.
(Reproduced by generic/167 over NFS atop XFS)
Signed-off-by: Christoph Hellwig <hch@lst.de>
[darrick.wong@oracle.com: add commit message]
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Start constructing the refcount btree implementation by establishing
the on-disk format and everything needed to read, write, and
manipulate the refcount btree blocks.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
The rmap btrees will use the AGFL as the block allocation source, so
we need to ensure that the transaction reservations reflect the fact
this tree is modified by allocation and freeing. Hence we need to
extend all the extent allocation/free reservations used in
transactions to handle this.
Note that this also gets rid of the unused XFS_ALLOCFREE_LOG_RES
macro, as we now do buffer reservations based on the number of
buffers logged via xfs_calc_buf_res(). Hence we only need the buffer
count calculation now.
[darrick: use rmap_maxlevels when calculating log block resv]
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Drop the compatibility shims that we were using to integrate the new
deferred operation mechanism into the existing code. No new code.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
We now have several superblock loggin functions that are identical
except for the transaction reservation and whether it shoul dbe a
synchronous transaction or not. Consolidate these all into a single
function, a single reserveration and a sync flag and call it
xfs_sync_sb().
Also, xfs_mod_sb() is not really a modification function - it's the
operation of logging the superblock buffer. hence change the name of
it to reflect this.
Note that we have to change the mp->m_update_flags that are passed
around at mount time to a boolean simply to indicate a superblock
update is needed.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
More on-disk format consolidation.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
More on-disk format consolidation. A few declarations that weren't on-disk
format related move into better suitable spots.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Move all the source files that are shared with userspace into
libxfs/. This is done as one big chunk simpy to get it done
quickly
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
