ext3: Add replace-on-rename hueristics for data=writeback mode

In data=writeback mode, start an asynchronous flush when renaming a
file on top of an already-existing file.  This lowers the probability
of data loss in the case of applications that attempt to replace a
file via using rename().

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This commit is contained in:
Theodore Ts'o 2009-04-03 01:34:49 -04:00
parent f7ab34ea72
commit e7c8f5079e

View file

@ -2265,7 +2265,7 @@ static int ext3_rename (struct inode * old_dir, struct dentry *old_dentry,
struct inode * old_inode, * new_inode;
struct buffer_head * old_bh, * new_bh, * dir_bh;
struct ext3_dir_entry_2 * old_de, * new_de;
int retval;
int retval, flush_file = 0;
old_bh = new_bh = dir_bh = NULL;
@ -2401,6 +2401,8 @@ static int ext3_rename (struct inode * old_dir, struct dentry *old_dentry,
ext3_mark_inode_dirty(handle, new_inode);
if (!new_inode->i_nlink)
ext3_orphan_add(handle, new_inode);
if (ext3_should_writeback_data(new_inode))
flush_file = 1;
}
retval = 0;
@ -2409,6 +2411,8 @@ end_rename:
brelse (old_bh);
brelse (new_bh);
ext3_journal_stop(handle);
if (retval == 0 && flush_file)
filemap_flush(old_inode->i_mapping);
return retval;
}