X-Git-Url: https://git.camperquake.de/gitweb.cgi?a=blobdiff_plain;f=include%2Flinux%2Fdcache_compat.h;fp=include%2Flinux%2Fdcache_compat.h;h=2b9e5c1c405095cd7b11e4ae8a0a953d58557846;hb=bf01b5e6161b4aa94c69792e50de4102a033be09;hp=271a0cbef76adfd8bdb72f07363aa0549f7bb3c8;hpb=1305d33a4b0f8b10cea61989330cc5d059cfa7cb;p=zfs.git

diff --git a/include/linux/dcache_compat.h b/include/linux/dcache_compat.h
index 271a0cb..2b9e5c1 100644
--- a/include/linux/dcache_compat.h
+++ b/include/linux/dcache_compat.h
@@ -60,4 +60,24 @@ d_set_d_op(struct dentry *dentry, dentry_operations_t *op)
 }
 #endif /* HAVE_D_SET_D_OP */
 
+/*
+ * 2.6.38 API addition,
+ * Added d_clear_d_op() helper function which clears some flags and the
+ * registered dentry->d_op table.  This is required because d_set_d_op()
+ * issues a warning when the dentry operations table is already set.
+ * For the .zfs control directory to work properly we must be able to
+ * override the default operations table and register custom .d_automount
+ * and .d_revalidate callbacks.
+ */
+static inline void
+d_clear_d_op(struct dentry *dentry)
+{
+#ifdef HAVE_D_SET_D_OP
+	dentry->d_op = NULL;
+	dentry->d_flags &=
+	    ~(DCACHE_OP_HASH | DCACHE_OP_COMPARE |
+	      DCACHE_OP_REVALIDATE | DCACHE_OP_DELETE);
+#endif /* HAVE_D_SET_D_OP */
+}
+
 #endif /* _ZFS_DCACHE_H */