Initial revision

1 files changed, 138 insertions, 0 deletions

diff --git a/devio/devpager.c b/devio/devpager.c
new file mode 100644
index 00000000..9ed5bd3e
--- /dev/null
+++ b/devio/devpager.c
@@ -0,0 +1,138 @@
+/* A pager interface for raw mach devices.
+
+   Copyright (C) 1995 Free Software Foundation, Inc.
+
+   Written by Miles Bader <miles@gnu.ai.mit.edu>
+
+   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 <hurd.h>
+#include <hurd/pager.h>
+#include <device/device.h>
+#include <assert.h>
+
+#include "dev.h"
+#include "ptypes.h"
+
+/* ---------------------------------------------------------------- */
+/* Pager library callbacks; see <hurd/pager.h> for more info.  */
+
+/* This will be the type used in calls to allocate_port by the pager system.
+ */
+int pager_port_type = PT_MEMOBJ;
+
+/* For pager PAGER, read one page from offset PAGE.  Set *BUF to be the
+   address of the page, and set *WRITE_LOCK if the page must be provided
+   read-only.  The only permissable error returns are EIO, EDQUOT, and
+   ENOSPC. */
+error_t
+pager_read_page(struct user_pager_info *upi,
+		vm_offset_t page, vm_address_t *buf, int *writelock)
+{
+  int read;			/* bytes actually read */
+  struct dev *dev = (struct dev *)upi;
+  error_t err =
+    device_read(dev->port,
+		0, page / dev->dev_block_size, vm_page_size,
+		(io_buf_ptr_t *)buf, &read);
+#ifdef MSG
+  if (debug)
+    {
+      mutex_lock(&debug_lock);
+      fprintf(debug, "device_read(%d, %d) [pager] => %s, %s, %d\n",
+	      page / dev->dev_block_size, vm_page_size,
+	      strerror(err), err ? "-" : brep(*buf, read), read);
+      mutex_unlock(&debug_lock);
+    }
+#endif
+
+  *writelock = (dev->flags & DEV_READONLY);
+
+  if (err || read < vm_page_size)
+    return EIO;
+  else
+    return 0;
+}
+
+/* For pager PAGER, synchronously write one page from BUF to offset PAGE.  In
+   addition, vm_deallocate (or equivalent) BUF.  The only permissable error
+   returns are EIO, EDQUOT, and ENOSPC. */
+error_t
+pager_write_page(struct user_pager_info *upi,
+		 vm_offset_t page, vm_address_t buf)
+{
+  struct dev *dev = (struct dev *)upi;
+
+  if (dev->flags & DEV_READONLY)
+    return EROFS;
+  else
+    {
+      int written;
+      error_t err =
+	device_write(dev->port,
+		     0, page / dev->dev_block_size,
+		     (io_buf_ptr_t)buf, vm_page_size,
+		     &written);
+#ifdef MSG
+      if (debug)
+	{
+	  mutex_lock(&debug_lock);
+	  fprintf(debug, "device_write(%d, %s, %d) [pager] => %s, %d\n",
+		  page / dev->dev_block_size,
+		  brep(buf, vm_page_size), vm_page_size,
+		  strerror(err), written);
+	  mutex_unlock(&debug_lock);
+	}
+#endif
+
+      vm_deallocate(mach_task_self(), buf, vm_page_size);
+
+      if (err || written < vm_page_size)
+	return EIO;
+      else
+	return 0;
+    }
+}
+
+/* A page should be made writable. */
+error_t
+pager_unlock_page(struct user_pager_info *upi, vm_offset_t address)
+{
+  struct dev *dev = (struct dev *)upi;
+
+  if (dev->flags & DEV_READONLY)
+    return EROFS;
+  else
+    return 0;
+}
+
+/* The user must define this function.  It should report back (in
+   *OFFSET and *SIZE the minimum valid address the pager will accept
+   and the size of the object.   */
+error_t
+pager_report_extent(struct user_pager_info *upi,
+		    vm_address_t *offset, vm_size_t *size)
+{
+  *offset = 0;
+  *size = ((struct dev *)upi)->size;
+  return 0;
+}
+
+/* This is called when a pager is being deallocated after all extant send
+   rights have been destroyed.  */
+void
+pager_clear_user_data(struct user_pager_info *upi)
+{
+}