[PATCH 8/9] xfs: take m_growlock when running growfsrt

Darrick J. Wong
2024-08-23T00:00:51Z

From: Darrick J. Wong <djwong@kernel.org>

Take the grow lock when we're expanding the realtime volume, like we do
for the other growfs calls.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
---
fs/xfs/xfs_rtalloc.c | 38 +++++++++++++++++++++++++-------------
1 file changed, 25 insertions(+), 13 deletions(-)

diff --git a/fs/xfs/xfs_rtalloc.c b/fs/xfs/xfs_rtalloc.c
index 0c3e96c621a67..776d6c401f62f 100644
--- a/fs/xfs/xfs_rtalloc.c
+++ b/fs/xfs/xfs_rtalloc.c
@@ -821,34 +821,39 @@ xfs_growfs_rt(
/* Needs to have been mounted with an rt device. */
if (!XFS_IS_REALTIME_MOUNT(mp))
return -EINVAL;
+
+ if (!mutex_trylock(&mp->m_growlock))
+ return -EWOULDBLOCK;
/*
* Mount should fail if the rt bitmap/summary files don't load, but
* we'll check anyway.
*/
+ error = -EINVAL;
if (!mp->m_rbmip || !mp->m_rsumip)
- return -EINVAL;
+ goto out_unlock;

/* Shrink not supported. */
if (in->newblocks <= sbp->sb_rblocks)
- return -EINVAL;
+ goto out_unlock;

/* Can only change rt extent size when adding rt volume. */
if (sbp->sb_rblocks > 0 && in->extsize != sbp->sb_rextsize)
- return -EINVAL;
+ goto out_unlock;

/* Range check the extent size. */
if (XFS_FSB_TO_B(mp, in->extsize) > XFS_MAX_RTEXTSIZE ||
XFS_FSB_TO_B(mp, in->extsize) < XFS_MIN_RTEXTSIZE)
- return -EINVAL;
+ goto out_unlock;

/* Unsupported realtime features. */
+ error = -EOPNOTSUPP;
if (xfs_has_rmapbt(mp) || xfs_has_reflink(mp) || xfs_has_quota(mp))
- return -EOPNOTSUPP;
+ goto out_unlock;

nrblocks = in->newblocks;
error = xfs_sb_validate_fsb_count(sbp, nrblocks);
if (error)
- return error;
+ goto out_unlock;
/*
* Read in the last block of the device, make sure it exists.
*/
@@ -856,7 +861,7 @@ xfs_growfs_rt(
XFS_FSB_TO_BB(mp, nrblocks - 1),
XFS_FSB_TO_BB(mp, 1), 0, &bp, NULL);
if (error)
- return error;
+ goto out_unlock;
xfs_buf_relse(bp);

/*
@@ -864,8 +869,10 @@ xfs_growfs_rt(
*/
nrextents = nrblocks;
do_div(nrextents, in->extsize);
- if (!xfs_validate_rtextents(nrextents))
- return -EINVAL;
+ if (!xfs_validate_rtextents(nrextents)) {
+ error = -EINVAL;
+ goto out_unlock;
+ }
nrbmblocks = xfs_rtbitmap_blockcount(mp, nrextents);
nrextslog = xfs_compute_rextslog(nrextents);
nrsumlevels = nrextslog + 1;
@@ -876,8 +883,11 @@ xfs_growfs_rt(
* the log. This prevents us from getting a log overflow,
* since we'll log basically the whole summary file at once.
*/
- if (nrsumblocks > (mp->m_sb.sb_logblocks >> 1))
- return -EINVAL;
+ if (nrsumblocks > (mp->m_sb.sb_logblocks >> 1)) {
+ error = -EINVAL;
+ goto out_unlock;
+ }
+
/*
* Get the old block counts for bitmap and summary inodes.
* These can't change since other growfs callers are locked out.
@@ -889,10 +899,10 @@ xfs_growfs_rt(
*/
error = xfs_growfs_rt_alloc(mp, rbmblocks, nrbmblocks, mp->m_rbmip);
if (error)
- return error;
+ goto out_unlock;
error = xfs_growfs_rt_alloc(mp, rsumblocks, nrsumblocks, mp->m_rsumip);
if (error)
- return error;
+ goto out_unlock;

rsum_cache = mp->m_rsum_cache;
if (nrbmblocks != sbp->sb_rbmblocks)
@@ -1059,6 +1069,8 @@ xfs_growfs_rt(
}
}

+out_unlock:
+ mutex_unlock(&mp->m_growlock);
return error;
}