New helper - simple_fsync()
writes associated buffers, then does sync_inode() to write
the inode itself (and to make it clean). Depends on
->write_inode() honouring the second argument.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/libfs.c b/fs/libfs.c
index 80046dd..ddfa899 100644
--- a/fs/libfs.c
+++ b/fs/libfs.c
@@ -9,6 +9,8 @@
#include <linux/vfs.h>
#include <linux/mutex.h>
#include <linux/exportfs.h>
+#include <linux/writeback.h>
+#include <linux/buffer_head.h>
#include <asm/uaccess.h>
@@ -807,6 +809,29 @@
}
EXPORT_SYMBOL_GPL(generic_fh_to_parent);
+int simple_fsync(struct file *file, struct dentry *dentry, int datasync)
+{
+ struct writeback_control wbc = {
+ .sync_mode = WB_SYNC_ALL,
+ .nr_to_write = 0, /* metadata-only; caller takes care of data */
+ };
+ struct inode *inode = dentry->d_inode;
+ int err;
+ int ret;
+
+ ret = sync_mapping_buffers(inode->i_mapping);
+ if (!(inode->i_state & I_DIRTY))
+ return ret;
+ if (datasync && !(inode->i_state & I_DIRTY_DATASYNC))
+ return ret;
+
+ err = sync_inode(inode, &wbc);
+ if (ret == 0)
+ ret = err;
+ return ret;
+}
+EXPORT_SYMBOL(simple_fsync);
+
EXPORT_SYMBOL(dcache_dir_close);
EXPORT_SYMBOL(dcache_dir_lseek);
EXPORT_SYMBOL(dcache_dir_open);
diff --git a/include/linux/fs.h b/include/linux/fs.h
index d883aa1..ede84fa 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2345,6 +2345,8 @@
extern ssize_t simple_read_from_buffer(void __user *to, size_t count,
loff_t *ppos, const void *from, size_t available);
+extern int simple_fsync(struct file *, struct dentry *, int);
+
#ifdef CONFIG_MIGRATION
extern int buffer_migrate_page(struct address_space *,
struct page *, struct page *);