1 files changed, 122 insertions, 0 deletions
diff --git a/libpager/mark-error.c b/libpager/mark-error.c
new file mode 100644
index 00000000..8b031479
--- /dev/null
+++ b/libpager/mark-error.c
@@ -0,0 +1,122 @@
+/* Recording errors for pager library
+   Copyright (C) 1994, 1997 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"
+
+
+int _pager_page_errors[] = {KERN_SUCCESS, ENOSPC, EIO, EDQUOT};
+
+/* Some error has happened indicating that the page cannot be written. 
+   (Usually this is ENOSPC or EDQOUT.)  On the next pagein which
+   requests write access, return the error to the kernel.  (This is 
+   screwy because of the rules associated with m_o_lock_request.)
+   Currently the only errors permitted are ENOSPC, EIO, and EDQUOT.  */
+void
+_pager_mark_next_request_error(struct pager *pager,
+			       vm_address_t offset,
+			       vm_size_t length,
+			       error_t error)
+{
+  int page_error;
+  char *p;
+
+  offset /= __vm_page_size;
+  length /= __vm_page_size;
+  
+  switch (error)
+    {
+    case 0:
+      page_error = PAGE_NOERR;
+      break;
+    case ENOSPC:
+      page_error = PAGE_ENOSPC;
+      break;
+    case EIO:
+    default:
+      page_error = PAGE_EIO;
+      break;
+    case EDQUOT:
+      page_error = PAGE_EDQUOT;
+      break;
+    }
+  
+  for (p = pager->pagemap + offset; p < pager->pagemap + offset + length; p++)
+    *p = SET_PM_NEXTERROR (*p, page_error);
+}
+
+/* We are returning a pager error to the kernel.  Write down
+   in the pager what that error was so that the exception handling
+   routines can find out.  (This is only necessary because the
+   XP interface is not completely implemented in the kernel.)
+   Again, only ENOSPC, EIO, and EDQUOT are permitted.  */
+void
+_pager_mark_object_error(struct pager *pager,
+			 vm_address_t offset,
+			 vm_size_t length,
+			 error_t error)
+{
+  int page_error = 0;
+  char *p;
+
+  offset /= __vm_page_size;
+  length /= __vm_page_size;
+  
+  switch (error)
+    {
+    case 0:
+      page_error = PAGE_NOERR;
+      break;
+    case ENOSPC:
+      page_error = PAGE_ENOSPC;
+      break;
+    case EIO:
+    default:
+      page_error = PAGE_EIO;
+      break;
+    case EDQUOT:
+      page_error = PAGE_EDQUOT;
+      break;
+    }
+  
+  for (p = pager->pagemap + offset; p < pager->pagemap + offset + length; p++)
+    *p = SET_PM_ERROR (*p, page_error);
+}
+
+/* Tell us what the error (set with mark_object_error) for 
+   pager P is on page ADDR. */
+error_t
+pager_get_error (struct pager *p, vm_address_t addr)
+{
+  error_t err;
+  
+  mutex_lock (&p->interlock);
+
+  addr /= vm_page_size;
+
+  /* If there really is no error for ADDR, we should be able to exted the
+     pagemap table; otherwise, if some previous operation failed because it
+     couldn't extend the table, this attempt will *probably* (heh) fail for
+     the same reason.  */
+  err = _pager_pagemap_resize (p, addr);
+
+  if (! err)
+    err = _pager_page_errors[PM_ERROR(p->pagemap[addr])];
+
+  mutex_unlock (&p->interlock);
+
+  return err;
+}