Commit fde87268 authored by Theodore Ts'o's avatar Theodore Ts'o
Browse files

ext4: force inode writes when nfsd calls commit_metadata() 



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: default avatarTheodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
parent 8a363970

fs/ext4/super.c

+11 −0
Original line number Diff line number Diff line
@@ -1202,6 +1202,16 @@ static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid, 
				    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
@@ -1406,6 +1416,7 @@ static const struct export_operations ext4_export_ops = { 
	.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 {

include/trace/events/ext4.h

+20 −0
Original line number Diff line number Diff line
@@ -226,6 +226,26 @@ 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),

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