1 files changed, 90 insertions, 0 deletions
diff --git a/libpager/data-unlock.c b/libpager/data-unlock.c
new file mode 100644
index 00000000..a4ef0600
--- /dev/null
+++ b/libpager/data-unlock.c
@@ -0,0 +1,90 @@
+/* Implementation of memory_object_data_unlock for pager library
+   Copyright (C) 1994, 1995 Free Software Foundation
+
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License as
+   published by the Free Software Foundation; either version 2, or (at
+   your option) any later version.
+
+   This program is distributed in the hope that it will be useful, but
+   WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
+
+#include "priv.h"
+#include "memory_object_S.h"
+#include <stdio.h>
+
+/* Implement kernel requests for access as described in 
+   <mach/memory_object.defs>. */
+kern_return_t
+_pager_seqnos_memory_object_data_unlock (mach_port_t object, 
+					 mach_port_seqno_t seqno,
+					 mach_port_t control,
+					 vm_offset_t offset,
+					 vm_size_t length,
+					 vm_prot_t access)
+{
+  struct pager *p;
+  volatile int err;
+  
+  p = ports_lookup_port (0, object, _pager_class);
+  if (!p)
+    return EOPNOTSUPP;
+
+  mutex_lock (&p->interlock);
+  _pager_wait_for_seqno (p, seqno);
+  _pager_release_seqno (p, seqno);
+  mutex_unlock (&p->interlock);
+
+  if (p->pager_state != NORMAL)
+    {
+      printf ("pager in wrong state for unlock\n");
+      goto out;
+    }
+
+  if (control != p->memobjcntl)
+    {
+      printf ("incg data unlock: wrong control port\n");
+      goto out;
+    }
+  /* The only thing we ever block is writes */
+  if ((access & VM_PROT_WRITE) == 0)
+    {
+      printf ("incg data unlock: not unlock writes\n");
+      goto out;
+    }
+  if (offset % __vm_page_size)
+    {
+      printf ("incg data unlock: misaligned request\n");
+      goto out;
+    }
+  if (length != __vm_page_size)
+    {
+      printf ("incg data unlock: bad length size %d\n", length);
+      goto out;
+    }
+
+  err = pager_unlock_page (p->upi, offset);
+  
+  if (!err)
+    /* We can go ahead and release the lock.  */
+    _pager_lock_object (p, offset, length, MEMORY_OBJECT_RETURN_NONE, 0,
+			VM_PROT_NONE, 0);
+  else
+    {
+      /* Flush the page, and set a bit so that m_o_data_request knows
+	 to issue an error.  */
+      _pager_lock_object (p, offset, length, MEMORY_OBJECT_RETURN_NONE, 1,
+			  VM_PROT_WRITE, 1);
+      _pager_mark_next_request_error (p, offset, length, err);
+    }
+ out:
+  ports_port_deref (p);
+  return 0;
+}
+