fs: rcu-walk aware d_revalidate method
Require filesystems be aware of .d_revalidate being called in rcu-walk
mode (nd->flags & LOOKUP_RCU). For now do a simple push down, returning
-ECHILD from all implementations.
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
diff --git a/fs/autofs4/root.c b/fs/autofs4/root.c
index bfe3f2e..651e4ef 100644
--- a/fs/autofs4/root.c
+++ b/fs/autofs4/root.c
@@ -315,12 +315,19 @@
*/
static int autofs4_revalidate(struct dentry *dentry, struct nameidata *nd)
{
- struct inode *dir = dentry->d_parent->d_inode;
- struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb);
- int oz_mode = autofs4_oz_mode(sbi);
+ struct inode *dir;
+ struct autofs_sb_info *sbi;
+ int oz_mode;
int flags = nd ? nd->flags : 0;
int status = 1;
+ if (flags & LOOKUP_RCU)
+ return -ECHILD;
+
+ dir = dentry->d_parent->d_inode;
+ sbi = autofs4_sbi(dir->i_sb);
+ oz_mode = autofs4_oz_mode(sbi);
+
/* Pending dentry */
spin_lock(&sbi->fs_lock);
if (autofs4_ispending(dentry)) {