From: "Darrick J. Wong" darrick.wong@oracle.com
[ Upstream commit f959b5d037e71a4d69b5bf71faffa065d9269b4a ]
xfs_trans_dqresv is the function that we use to make reservations against resource quotas. Each resource contains two counters: the q_core counter, which tracks resources allocated on disk; and the dquot reservation counter, which tracks how much of that resource has either been allocated or reserved by threads that are working on metadata updates.
For disk blocks, we compare the proposed reservation counter against the hard and soft limits to decide if we're going to fail the operation. However, for inodes we inexplicably compare against the q_core counter, not the incore reservation count.
Since the q_core counter is always lower than the reservation count and we unlock the dquot between reservation and transaction commit, this means that multiple threads can reserve the last inode count before we hit the hard limit, and when they commit, we'll be well over the hard limit.
Fix this by checking against the incore inode reservation counter, since we would appear to maintain that correctly (and that's what we report in GETQUOTA).
Signed-off-by: Darrick J. Wong darrick.wong@oracle.com Reviewed-by: Allison Collins allison.henderson@oracle.com Reviewed-by: Chandan Babu R chandanrlinux@gmail.com Reviewed-by: Christoph Hellwig hch@lst.de Signed-off-by: Sasha Levin sashal@kernel.org --- fs/xfs/xfs_trans_dquot.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/xfs/xfs_trans_dquot.c b/fs/xfs/xfs_trans_dquot.c index c0f73b82c0551..ed0ce8b301b40 100644 --- a/fs/xfs/xfs_trans_dquot.c +++ b/fs/xfs/xfs_trans_dquot.c @@ -647,7 +647,7 @@ xfs_trans_dqresv( } } if (ninos > 0) { - total_count = be64_to_cpu(dqp->q_core.d_icount) + ninos; + total_count = dqp->q_res_icount + ninos; timer = be32_to_cpu(dqp->q_core.d_itimer); warns = be16_to_cpu(dqp->q_core.d_iwarns); warnlimit = defq->iwarnlimit;