vfs: update documentation on ->i_dentry handling

we used to need to clean it in RCU callback freeing an inode;
in 3.2 that requirement went away.  Unfortunately, it hadn't
been reflected in Documentation/filesystems/porting.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2012-06-09 11:55:20 -04:00
parent 7968ce12e9
commit 049b3c10ee

View File

@ -355,12 +355,10 @@ protects *all* the dcache state of a given dentry.
via rcu-walk path walk (basically, if the file can have had a path name in the
vfs namespace).
i_dentry and i_rcu share storage in a union, and the vfs expects
i_dentry to be reinitialized before it is freed, so an:
INIT_LIST_HEAD(&inode->i_dentry);
must be done in the RCU callback.
Even though i_dentry and i_rcu share storage in a union, we will
initialize the former in inode_init_always(), so just leave it alone in
the callback. It used to be necessary to clean it there, but not anymore
(starting at 3.2).
--
[recommended]