kern: vfs: Add NAMEI_PARENT flag to NAMEI

This flag allows one to get the vnode of the parent component rather
than the last

Signed-off-by: Ian Moffett <ian@osmora.org>

2 files changed, 13 insertions, 1 deletions

diff --git a/sys/inc/kern/namei.h b/sys/inc/kern/namei.h
index a9fba7f..5dbf5ad 100644
--- a/sys/inc/kern/namei.h
+++ b/sys/inc/kern/namei.h
@@ -33,6 +33,8 @@
 #include <sys/types.h>
 #include <sys/param.h>
 
+#define NAMEI_PARENT BIT(0)
+
 /*
  * Represents arguments to be passed with namei()
  */
diff --git a/sys/kern/kern_namei.c b/sys/kern/kern_namei.c
index cc11116..703cebb 100644
--- a/sys/kern/kern_namei.c
+++ b/sys/kern/kern_namei.c
@@ -38,6 +38,7 @@ namei(struct nameidata *ndp)
     struct vops *vops;
     struct mount *mpoint = NULL;
     struct vnode *vp = NULL;
+    struct vnode *parent = NULL;
     const char *p;
     int error;
     char namebuf[NAME_MAX];
@@ -88,8 +89,13 @@ namei(struct nameidata *ndp)
             continue;
         }
 
+        parent = vp;
         vops = &vp->vops;
         error = vnode_lookup(vp, namebuf, &vp);
+        if (error != 0 && ISSET(ndp->flags, NAMEI_PARENT)) {
+            break;
+        }
+
         if (error != 0) {
             return error;
         }
@@ -97,6 +103,10 @@ namei(struct nameidata *ndp)
         namebuf_idx = 0;
     }
 
-    *ndp->vp_res = vp;
+    if (ISSET(ndp->flags, NAMEI_PARENT)) {
+        *ndp->vp_res = parent;
+    } else {
+        *ndp->vp_res = vp;
+    }
     return 0;
 }