fs: change d_compare for rcu-walk
Change d_compare so it may be called from lock-free RCU lookups. This
does put significant restrictions on what may be done from the callback,
however there don't seem to have been any problems with in-tree fses.
If some strange use case pops up that _really_ cannot cope with the
rcu-walk rules, we can just add new rcu-unaware callbacks, which would
cause name lookup to drop out of rcu-walk mode.
For in-tree filesystems, this is just a mechanical change.
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking
index 33fa3e5..9a76f8d 100644
--- a/Documentation/filesystems/Locking
+++ b/Documentation/filesystems/Locking
@@ -11,7 +11,9 @@
prototypes:
int (*d_revalidate)(struct dentry *, int);
int (*d_hash) (struct dentry *, struct qstr *);
- int (*d_compare) (struct dentry *, struct qstr *, struct qstr *);
+ int (*d_compare)(const struct dentry *, const struct inode *,
+ const struct dentry *, const struct inode *,
+ unsigned int, const char *, const struct qstr *);
int (*d_delete)(struct dentry *);
void (*d_release)(struct dentry *);
void (*d_iput)(struct dentry *, struct inode *);