3.16.65-rc1 review patch. If anyone has any objections, please let me know.
------------------
From: Theodore Ts'o <tytso@xxxxxxx>
commit fde872682e175743e0c3ef939c89e3c6008a1529 upstream.
Some time back, nfsd switched from calling vfs_fsync() to using a new
commit_metadata() hook in export_operations(). If the file system did
not provide a commit_metadata() hook, it fell back to using
sync_inode_metadata(). Unfortunately doesn't work on all file
systems. In particular, it doesn't work on ext4 due to how the inode
gets journalled --- the VFS writeback code will not always call
ext4_write_inode().
So we need to provide our own ext4_nfs_commit_metdata() method which
calls ext4_write_inode() directly.
Google-Bug-Id: 121195940
Signed-off-by: Theodore Ts'o <tytso@xxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
fs/ext4/super.c | 11 +++++++++++
include/trace/events/ext4.h | 20 ++++++++++++++++++++
2 files changed, 31 insertions(+)
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1042,6 +1042,16 @@ static struct dentry *ext4_fh_to_parent(
ext4_nfs_get_inode);
}
+static int ext4_nfs_commit_metadata(struct inode *inode)
+{
+ struct writeback_control wbc = {
+ .sync_mode = WB_SYNC_ALL
+ };
+
+ trace_ext4_nfs_commit_metadata(inode);
+ return ext4_write_inode(inode, &wbc);
+}
+
/*
* Try to release metadata pages (indirect blocks, directories) which are
* mapped via the block device. Since these pages could have journal heads
@@ -1162,6 +1172,7 @@ static const struct export_operations ex
.fh_to_dentry = ext4_fh_to_dentry,
.fh_to_parent = ext4_fh_to_parent,
.get_parent = ext4_get_parent,
+ .commit_metadata = ext4_nfs_commit_metadata,
};
enum {
--- a/include/trace/events/ext4.h
+++ b/include/trace/events/ext4.h
@@ -195,6 +195,26 @@ TRACE_EVENT(ext4_drop_inode,
(unsigned long) __entry->ino, __entry->drop)
);
+TRACE_EVENT(ext4_nfs_commit_metadata,
+ TP_PROTO(struct inode *inode),
+
+ TP_ARGS(inode),
+
+ TP_STRUCT__entry(
+ __field( dev_t, dev )
+ __field( ino_t, ino )
+ ),
+
+ TP_fast_assign(
+ __entry->dev = inode->i_sb->s_dev;
+ __entry->ino = inode->i_ino;
+ ),
+
+ TP_printk("dev %d,%d ino %lu",
+ MAJOR(__entry->dev), MINOR(__entry->dev),
+ (unsigned long) __entry->ino)
+);
+
TRACE_EVENT(ext4_mark_inode_dirty,
TP_PROTO(struct inode *inode, unsigned long IP),
