From 3beb81a5d0b12a2c1cd61d061f76e8a9827ef6fa Mon Sep 17 00:00:00 2001
From: Ben Gras <ben@minix3.org>
Date: Thu, 10 Feb 2011 15:39:56 +0000
Subject: [PATCH] memory driver: munmap() imgrd after first close.

(that munmap() range not supported yet by vm.)
---
 drivers/memory/memory.c | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/drivers/memory/memory.c b/drivers/memory/memory.c
index a3e60e469..4ad14e8e3 100644
--- a/drivers/memory/memory.c
+++ b/drivers/memory/memory.c
@@ -20,6 +20,7 @@
 #include <sys/ioc_memory.h>
 #include <minix/ds.h>
 #include <minix/vm.h>
+#include <machine/param.h>
 #include <sys/mman.h>
 #include "kernel/const.h"
 #include "kernel/config.h"
@@ -393,6 +394,28 @@ message *m_ptr;
   }
   openct[m_device]--;
 
+  /* Special case: free initial ramdisk after it's been unmounted once. */
+  if(m_device == IMGRD_DEV && openct[m_device] == 0 && m_vaddrs[IMGRD_DEV]) {
+  	vir_bytes vaddr, vlen;
+	vaddr = m_vaddrs[IMGRD_DEV];
+	vlen = imgrd_size;
+	/* Align `inwards' so as to not unmap more than the initial
+	 * ramdisk image.
+	 */
+	if(vaddr % PAGE_SIZE) {
+		vir_bytes o = PAGE_SIZE - (vaddr % PAGE_SIZE);
+		vlen -= o;
+		vaddr += o;
+	}
+	if(vlen % PAGE_SIZE) {
+		vlen -= vlen % PAGE_SIZE;
+	}
+	munmap((void *) vaddr, vlen);
+	m_geom[IMGRD_DEV].dv_base= cvul64(0);
+	m_geom[IMGRD_DEV].dv_size= cvul64(0);
+	m_vaddrs[IMGRD_DEV] = 0;
+  }
+
   return(OK);
 }
 
-- 
2.44.0