Commit 85ce127a authored Jul 21, 2013 by Yan, Zheng Committed by Sage Weil Aug 09, 2013

ceph: wake up writer if vmtruncate work get blocked

To write data, the writer first acquires the i_mutex, then try getting
caps. The writer may sleep while holding the i_mutex. If the MDS revokes
Fb cap in this case, vmtruncate work can't do its job because i_mutex
is locked. We should wake up the writer and let it truncate the pages.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Sage Weil <sage@inktank.com>

parent ad88f23f

fs/ceph/inode.c

+8 −1

Original line number	Diff line number	Diff line
		@@ -1465,7 +1465,14 @@ static void ceph_vmtruncate_work(struct work_struct *work)
		struct inode *inode = &ci->vfs_inode;

		dout("vmtruncate_work %p\n", inode);
		if (!mutex_trylock(&inode->i_mutex)) {
		/*
		* the i_mutex can be hold by a writer who is waiting for
		* caps. wake up waiters, they will do pending vmtruncate.
		*/
		wake_up_all(&ci->i_cap_wq);
		mutex_lock(&inode->i_mutex);
		}
		__ceph_do_pending_vmtruncate(inode);
		mutex_unlock(&inode->i_mutex);
		iput(inode);