writeback: remove .nonblocking and .encountered_congestion

Remove two unused struct writeback_control fields:

	.encountered_congestion	(completely unused)
	.nonblocking		(never set, checked/showed in XFS,NFS/btrfs)

The .for_background check in nfs_write_inode() is also removed btw,
as .for_background implies WB_SYNC_NONE.

Reviewed-by: Jan Kara <jack@suse.cz>
Proposed-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>

2 files changed, 2 insertions, 3 deletions

diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index e268e3b23497..dd6a6cee39a7 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -1564,8 +1564,7 @@ int nfs_write_inode(struct inode *inode, struct writeback_control *wbc)
                 int status;
                 bool sync = true;
 
-                if (wbc->sync_mode == WB_SYNC_NONE || wbc->nonblocking ||
-                    wbc->for_background)
+                if (wbc->sync_mode == WB_SYNC_NONE)
                         sync = false;
 
                 status = pnfs_layoutcommit_inode(inode, sync);
diff --git a/fs/xfs/linux-2.6/xfs_aops.c b/fs/xfs/linux-2.6/xfs_aops.c
index 79ce38be15a1..7559861481aa 100644
--- a/fs/xfs/linux-2.6/xfs_aops.c
+++ b/fs/xfs/linux-2.6/xfs_aops.c
@@ -970,7 +970,7 @@ xfs_vm_writepage(
         offset = page_offset(page);
         type = IO_OVERWRITE;
 
-        if (wbc->sync_mode == WB_SYNC_NONE && wbc->nonblocking)
+        if (wbc->sync_mode == WB_SYNC_NONE)
                 nonblocking = 1;
 
         do {