The aim of the inode btree record iterator function is to call a
callback on every record in the btree. To avoid having to tear down and
recreate the inode btree cursor around every callback, it caches a
certain number of records in a memory buffer. After each batch of
callback invocations, we have to perform a btree lookup to find the
next record after where we left off.
However, if the keys of the inode btree are corrupt, the lookup might
put us in the wrong part of the inode btree, causing the walk function
to loop forever. Therefore, we add extra cursor tracking to make sure
that we never go backwards neither when performing the lookup nor when
jumping to the next inobt record. This also fixes an off by one error
where upon resume the lookup should have been for the inode /after/ the
point at which we stopped.
Found by fuzzing xfs/460 with keys[2].startino = ones causing bulkstat
and quotacheck to hang.
Fixes: a211432c27 ("xfs: create simplified inode walk function")
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Use -ECANCELED to signal "stop iterating" instead of these magical
*_ITER_ABORT values, since it's duplicative.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Since no caller is using KM_NOSLEEP and no callee branches on KM_SLEEP,
we can remove KM_NOSLEEP and replace KM_SLEEP with 0.
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Add a new xfs_bulk_ireq flag to constrain the iteration to a single AG.
If the passed-in startino value is zero then we start with the first
inode in the AG that the user passes in; otherwise, we iterate only
within the same AG as the passed-in inode.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Allison Collins <allison.henderson@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Create a pwork destroy function that uses polling instead of
uninterruptible sleep to wait for work items to finish so that we can
touch the softlockup watchdog. IOWs, gross hack.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Create a parallel iwalk implementation and switch quotacheck to use it.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Refactor xfs_iwalk_ag_start and xfs_iwalk_ag so that the bits that are
particular to bulkstat (trimming the start irec, starting inode
readahead, and skipping empty groups) can be controlled via flags in the
iwag structure.
This enables us to add a new function to walk all inobt records which
will be used for the new INUMBERS implementation in the next patch.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
In preparation for reusing the iwalk code for the inogrp walking code
(aka INUMBERS), move the initial inobt lookup and retrieval code out of
xfs_iwalk_grab_ichunk so that we call the masking code only when we need
to trim out the inodes that came before the cursor in the inobt record
(aka BULKSTAT).
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Refactor xfs_iwalk_ichunk_ra to avoid long conditionals.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Now that the inode chunk grabbing function is a static function in the
iwalk code, change its behavior so that @agino is the inode where we
want to /start/ the iteration. This reduces cognitive friction with the
callers and simplifes the code.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Now that we've reworked the bulkstat code to use iwalk, we can move the
old bulkstat ichunk helpers to xfs_iwalk.c. No functional changes here.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
The existing inode walk prefetch is based on the old bulkstat code,
which simply allocated 4 pages worth of memory and prefetched that many
inobt records, regardless of however many inodes the caller requested.
65536 inodes is a lot to prefetch (~32M on x64, ~512M on arm64) so let's
scale things down a little more intelligently based on the number of
inodes requested, etc.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Create a new iterator function to simplify walking inodes in an XFS
filesystem. This new iterator will replace the existing open-coded
walking that goes on in various places.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
