• Al Viro's avatar
    dentry name snapshots · 407669f2
    Al Viro authored
    commit 49d31c2f upstream.
    
    take_dentry_name_snapshot() takes a safe snapshot of dentry name;
    if the name is a short one, it gets copied into caller-supplied
    structure, otherwise an extra reference to external name is grabbed
    (those are never modified).  In either case the pointer to stable
    string is stored into the same structure.
    
    dentry must be held by the caller of take_dentry_name_snapshot(),
    but may be freely dropped afterwards - the snapshot will stay
    until destroyed by release_dentry_name_snapshot().
    
    Intended use:
    	struct name_snapshot s;
    
    	take_dentry_name_snapshot(&s, dentry);
    	...
    	access s.name
    	...
    	release_dentry_name_snapshot(&s);
    
    Replaces fsnotify_oldname_...(), gets used in fsnotify to obtain the name
    to pass down with event.
    Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
    Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
    407669f2
namei.c 115 KB