[PATCH 3/5] xfs: use xfs_ilock_map_shared in xfs_qm_dqiterate

Christoph Hellwig
2013-12-05T15:59:53Z

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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>

Index: xfs/fs/xfs/xfs_qm.c
===================================================================
--- xfs.orig/fs/xfs/xfs_qm.c 2013-11-18 14:39:01.967589998 +0100
+++ xfs/fs/xfs/xfs_qm.c 2013-12-05 12:32:36.623617997 +0100
@@ -1193,16 +1193,18 @@ xfs_qm_dqiterate(
lblkno = 0;
maxlblkcnt = XFS_B_TO_FSB(mp, mp->m_super->s_maxbytes);
do {
+ uint lock_mode;
+
nmaps = XFS_DQITER_MAP_SIZE;
/*
* We aren't changing the inode itself. Just changing
* some of its data. No new blocks are added here, and
* the inode is never added to the transaction.
*/
- xfs_ilock(qip, XFS_ILOCK_SHARED);
+ lock_mode = xfs_ilock_map_shared(qip);
error = xfs_bmapi_read(qip, lblkno, maxlblkcnt - lblkno,
map, &nmaps, 0);
- xfs_iunlock(qip, XFS_ILOCK_SHARED);
+ xfs_iunlock_map_shared(qip, lock_mode);
if (error)
break;