NFSv4.2: Fix a race in nfs42_proc_deallocate()
When punching holes in a file, we want to ensure the operation is
serialised w.r.t. other writes, meaning that we want to call
nfs_sync_inode() while holding the inode lock.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
diff --git a/fs/nfs/nfs42proc.c b/fs/nfs/nfs42proc.c
index aa03ed0..0f9f536 100644
--- a/fs/nfs/nfs42proc.c
+++ b/fs/nfs/nfs42proc.c
@@ -113,15 +113,17 @@
if (!nfs_server_capable(inode, NFS_CAP_DEALLOCATE))
return -EOPNOTSUPP;
- nfs_wb_all(inode);
inode_lock(inode);
+ err = nfs_sync_inode(inode);
+ if (err)
+ goto out_unlock;
err = nfs42_proc_fallocate(&msg, filep, offset, len);
if (err == 0)
truncate_pagecache_range(inode, offset, (offset + len) -1);
if (err == -EOPNOTSUPP)
NFS_SERVER(inode)->caps &= ~NFS_CAP_DEALLOCATE;
-
+out_unlock:
inode_unlock(inode);
return err;
}