diff --git a/fs/xfs/xfs_qm_syscalls.c b/fs/xfs/xfs_qm_syscalls.c index c41190cad6e9..6cdf6ffc36a1 100644 --- a/fs/xfs/xfs_qm_syscalls.c +++ b/fs/xfs/xfs_qm_syscalls.c @@ -489,31 +489,36 @@ xfs_qm_scall_setqlim( if ((newlim->d_fieldmask & XFS_DQ_MASK) == 0) return 0; + /* + * We don't want to race with a quotaoff so take the quotaoff lock. + * We don't hold an inode lock, so there's nothing else to stop + * a quotaoff from happening. + */ + mutex_lock(&q->qi_quotaofflock); + + /* + * Get the dquot (locked) before we start, as we need to do a + * transaction to allocate it if it doesn't exist. Once we have the + * dquot, unlock it so we can start the next transaction safely. We hold + * a reference to the dquot, so it's safe to do this unlock/lock without + * it being reclaimed in the mean time. + */ + error = xfs_qm_dqget(mp, NULL, id, type, XFS_QMOPT_DQALLOC, &dqp); + if (error) { + ASSERT(error != ENOENT); + goto out_unlock; + } + xfs_dqunlock(dqp); + tp = xfs_trans_alloc(mp, XFS_TRANS_QM_SETQLIM); error = xfs_trans_reserve(tp, 0, XFS_QM_SETQLIM_LOG_RES(mp), 0, 0, XFS_DEFAULT_LOG_COUNT); if (error) { xfs_trans_cancel(tp, 0); - return (error); + goto out_rele; } - /* - * We don't want to race with a quotaoff so take the quotaoff lock. - * (We don't hold an inode lock, so there's nothing else to stop - * a quotaoff from happening). (XXXThis doesn't currently happen - * because we take the vfslock before calling xfs_qm_sysent). - */ - mutex_lock(&q->qi_quotaofflock); - - /* - * Get the dquot (locked), and join it to the transaction. - * Allocate the dquot if this doesn't exist. - */ - if ((error = xfs_qm_dqget(mp, NULL, id, type, XFS_QMOPT_DQALLOC, &dqp))) { - xfs_trans_cancel(tp, XFS_TRANS_ABORT); - ASSERT(error != ENOENT); - goto out_unlock; - } + xfs_dqlock(dqp); xfs_trans_dqjoin(tp, dqp); ddq = &dqp->q_core; @@ -621,9 +626,10 @@ xfs_qm_scall_setqlim( xfs_trans_log_dquot(tp, dqp); error = xfs_trans_commit(tp, 0); - xfs_qm_dqrele(dqp); - out_unlock: +out_rele: + xfs_qm_dqrele(dqp); +out_unlock: mutex_unlock(&q->qi_quotaofflock); return error; }