NFS: Write the entire file if a server reboot occurs during fsync()

This is to ensure that we don't clear the NFS_CONTEXT_RESEND_WRITES
flag while there are still writes that haven't been resent.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

2 files changed, 14 insertions, 0 deletions

diff --git a/fs/nfs/file.c b/fs/nfs/file.c
index cc9b56691bef..c814666bbe7f 100644
--- a/fs/nfs/file.c
+++ b/fs/nfs/file.c
@@ -301,6 +301,13 @@ nfs_file_fsync(struct file *file, loff_t start, loff_t end, int datasync)
                 mutex_lock(&inode->i_mutex);
                 ret = nfs_file_fsync_commit(file, start, end, datasync);
                 mutex_unlock(&inode->i_mutex);
+                /*
+                 * If nfs_file_fsync_commit detected a server reboot, then
+                 * resend all dirty pages that might have been covered by
+                 * the NFS_CONTEXT_RESEND_WRITES flag
+                 */
+                start = 0;
+                end = LLONG_MAX;
         } while (ret == -EAGAIN);
 
         return ret;
diff --git a/fs/nfs/nfs4file.c b/fs/nfs/nfs4file.c
index eef1b38a1b08..afddd6639afb 100644
--- a/fs/nfs/nfs4file.c
+++ b/fs/nfs/nfs4file.c
@@ -105,6 +105,13 @@ nfs4_file_fsync(struct file *file, loff_t start, loff_t end, int datasync)
                         /* application has asked for meta-data sync */
                         ret = pnfs_layoutcommit_inode(inode, true);
                 mutex_unlock(&inode->i_mutex);
+                /*
+                 * If nfs_file_fsync_commit detected a server reboot, then
+                 * resend all dirty pages that might have been covered by
+                 * the NFS_CONTEXT_RESEND_WRITES flag
+                 */
+                start = 0;
+                end = LLONG_MAX;
         } while (ret == -EAGAIN);
 
         return ret;