xfs: use xfs_ilock_data_map_shared in xfs_qm_dqtobp

We might not have read in the extent list at this point, so make sure we
take the ilock exclusively if we have to do so.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
This commit is contained in:
Christoph Hellwig 2013-12-06 12:30:13 -08:00 committed by Ben Myers
parent 4f317369d4
commit f4df8adc83

View file

@ -469,16 +469,17 @@ xfs_qm_dqtobp(
struct xfs_mount *mp = dqp->q_mount;
xfs_dqid_t id = be32_to_cpu(dqp->q_core.d_id);
struct xfs_trans *tp = (tpp ? *tpp : NULL);
uint lock_mode;
dqp->q_fileoffset = (xfs_fileoff_t)id / mp->m_quotainfo->qi_dqperchunk;
xfs_ilock(quotip, XFS_ILOCK_SHARED);
lock_mode = xfs_ilock_data_map_shared(quotip);
if (!xfs_this_quota_on(dqp->q_mount, dqp->dq_flags)) {
/*
* Return if this type of quotas is turned off while we
* didn't have the quota inode lock.
*/
xfs_iunlock(quotip, XFS_ILOCK_SHARED);
xfs_iunlock(quotip, lock_mode);
return ESRCH;
}
@ -488,7 +489,7 @@ xfs_qm_dqtobp(
error = xfs_bmapi_read(quotip, dqp->q_fileoffset,
XFS_DQUOT_CLUSTER_SIZE_FSB, &map, &nmaps, 0);
xfs_iunlock(quotip, XFS_ILOCK_SHARED);
xfs_iunlock(quotip, lock_mode);
if (error)
return error;