nfs4: serialize layoutcommit

Current pnfs_layoutcommit_inode can not handle parallel layoutcommit.
And as Trond suggested , there is no need for client to optimize for
parallel layoutcommit. So add NFS_INO_LAYOUTCOMMITTING flag to
mark inflight layoutcommit and serialize lalyoutcommit with it.
Also mark_inode_dirty_sync if pnfs_layoutcommit_inode fails to issue
layoutcommit.

Reported-by: Vitaliy Gusev <gusev.vitaliy@nexenta.com>
Signed-off-by: Peng Tao <peng_tao@emc.com>
Signed-off-by: Jim Rees <rees@umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h
index 60a137b7f171..ab2c6343361a 100644
--- a/include/linux/nfs_fs.h
+++ b/include/linux/nfs_fs.h
@@ -229,6 +229,7 @@ struct nfs_inode {
 #define NFS_INO_COMMIT          (7)             /* inode is committing unstable writes */
 #define NFS_INO_PNFS_COMMIT     (8)             /* use pnfs code for commit */
 #define NFS_INO_LAYOUTCOMMIT    (9)             /* layoutcommit required */
+#define NFS_INO_LAYOUTCOMMITTING (10)           /* layoutcommit inflight */
 
 static inline struct nfs_inode *NFS_I(const struct inode *inode)
 {