From 87edb8940a47a3c775bfd26317174468e3dd9eec Mon Sep 17 00:00:00 2001
From: Vladimir 'phcoder' Serbinenko <phcoder@gmail.com>
Date: Tue, 24 Jan 2012 13:31:12 +0100
Subject: [PATCH] 	Replace single-linked with double-linked lists. It
 results in more 	compact and more efficient code.

	* grub-core/kern/list.c (grub_list_push): Moved from here ...
	* include/grub/list.h (grub_list_push): ... to here. Set prev.
	(grub_list_remove): Moved from here ...
	* include/grub/list.h (grub_list_remove): ... here. Use and set prev.
	(grub_prio_list_insert): Set prev.
	* include/grub/list.h (grub_list): Add prev. All users updated.
---
 ChangeLog                     | 12 ++++++++
 grub-core/bus/usb/usb.c       |  2 +-
 grub-core/commands/terminal.c | 11 ++++---
 grub-core/disk/ahci.c         |  1 +
 grub-core/gettext/gettext.c   |  1 +
 grub-core/kern/command.c      |  3 +-
 grub-core/kern/emu/hostdisk.c |  1 +
 grub-core/kern/list.c         | 23 ++-------------
 grub-core/loader/i386/xnu.c   |  6 ++--
 grub-core/net/net.c           |  7 ++---
 grub-core/net/tcp.c           | 12 ++++----
 grub-core/net/udp.c           |  4 +--
 grub-core/normal/auth.c       |  5 ++--
 grub-core/term/serial.c       |  2 +-
 grub-core/tests/lib/test.c    |  3 +-
 include/grub/command.h        |  1 +
 include/grub/cryptodisk.h     |  4 ++-
 include/grub/fs.h             |  3 +-
 include/grub/list.h           | 54 ++++++++++++++++++++++++-----------
 include/grub/net.h            |  7 +++--
 include/grub/partition.h      |  4 +--
 include/grub/serial.h         |  1 +
 include/grub/term.h           | 12 ++++----
 include/grub/test.h           |  1 +
 include/grub/usb.h            |  1 +
 include/grub/video.h          |  4 +--
 util/deviceiter.c             |  1 +
 27 files changed, 111 insertions(+), 75 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 79124720b..6f3b10818 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,15 @@
+2012-01-24  Vladimir Serbinenko  <phcoder@gmail.com>
+
+	Replace single-linked with double-linked lists. It results in more
+	compact and more efficient code.
+
+	* grub-core/kern/list.c (grub_list_push): Moved from here ...
+	* include/grub/list.h (grub_list_push): ... to here. Set prev.
+	(grub_list_remove): Moved from here ...
+	* include/grub/list.h (grub_list_remove): ... here. Use and set prev.
+	(grub_prio_list_insert): Set prev.
+	* include/grub/list.h (grub_list): Add prev. All users updated.
+
 2012-01-24  Vladimir Serbinenko  <phcoder@gmail.com>
 
 	Handle newer autotools. Add some missing quotes while on it.
diff --git a/grub-core/bus/usb/usb.c b/grub-core/bus/usb/usb.c
index cde57ced8..fb04e6572 100644
--- a/grub-core/bus/usb/usb.c
+++ b/grub-core/bus/usb/usb.c
@@ -340,7 +340,7 @@ grub_usb_register_attach_hook_class (struct grub_usb_attach_desc *desc)
 void
 grub_usb_unregister_attach_hook_class (struct grub_usb_attach_desc *desc)
 {
-  grub_list_remove (GRUB_AS_LIST_P (&attach_hooks), GRUB_AS_LIST (desc));  
+  grub_list_remove (GRUB_AS_LIST (desc));  
 }
 
 
diff --git a/grub-core/commands/terminal.c b/grub-core/commands/terminal.c
index 0adfd3d2e..7184ca44b 100644
--- a/grub-core/commands/terminal.c
+++ b/grub-core/commands/terminal.c
@@ -31,6 +31,7 @@ struct grub_term_autoload *grub_term_output_autoload = NULL;
 struct abstract_terminal
 {
   struct abstract_terminal *next;
+  struct abstract_terminal *prev;
   const char *name;
   grub_err_t (*init) (struct abstract_terminal *term);
   grub_err_t (*fini) (struct abstract_terminal *term);
@@ -137,7 +138,7 @@ handle_command (int argc, char **args, struct abstract_terminal **enabled,
               if (term->init && term->init (term) != GRUB_ERR_NONE)
                 return grub_errno;
 
-             grub_list_remove (GRUB_AS_LIST_P (disabled), GRUB_AS_LIST (term));
+             grub_list_remove (GRUB_AS_LIST (term));
              grub_list_push (GRUB_AS_LIST_P (enabled), GRUB_AS_LIST (term));
            }
        }
@@ -156,7 +157,7 @@ handle_command (int argc, char **args, struct abstract_terminal **enabled,
              if (!term->next && term == *enabled)
                return grub_error (GRUB_ERR_BAD_ARGUMENT,
                                   "can't remove the last terminal");
-             grub_list_remove (GRUB_AS_LIST_P (enabled), GRUB_AS_LIST (term));
+             grub_list_remove (GRUB_AS_LIST (term));
              if (term->fini)
                term->fini (term);
              grub_list_push (GRUB_AS_LIST_P (disabled), GRUB_AS_LIST (term));
@@ -174,7 +175,7 @@ handle_command (int argc, char **args, struct abstract_terminal **enabled,
          if (term->init && term->init (term) != GRUB_ERR_NONE)
            return grub_errno;
 
-         grub_list_remove (GRUB_AS_LIST_P (disabled), GRUB_AS_LIST (term));
+         grub_list_remove (GRUB_AS_LIST (term));
          grub_list_push (GRUB_AS_LIST_P (enabled), GRUB_AS_LIST (term));
        }       
     }
@@ -192,7 +193,7 @@ handle_command (int argc, char **args, struct abstract_terminal **enabled,
            if (!term->next && term == *enabled)
              return grub_error (GRUB_ERR_BAD_ARGUMENT,
                                 "can't remove the last terminal");
-           grub_list_remove (GRUB_AS_LIST_P (enabled), GRUB_AS_LIST (term));
+           grub_list_remove (GRUB_AS_LIST (term));
            if (term->fini)
              term->fini (term);
            grub_list_push (GRUB_AS_LIST_P (disabled), GRUB_AS_LIST (term));
@@ -208,6 +209,7 @@ grub_cmd_terminal_input (grub_command_t cmd __attribute__ ((unused)),
 			 int argc, char **args)
 {
   (void) GRUB_FIELD_MATCH (grub_term_inputs, struct abstract_terminal *, next);
+  (void) GRUB_FIELD_MATCH (grub_term_inputs, struct abstract_terminal *, prev);
   (void) GRUB_FIELD_MATCH (grub_term_inputs, struct abstract_terminal *, name);
   (void) GRUB_FIELD_MATCH (grub_term_inputs, struct abstract_terminal *, init);
   (void) GRUB_FIELD_MATCH (grub_term_inputs, struct abstract_terminal *, fini);
@@ -224,6 +226,7 @@ grub_cmd_terminal_output (grub_command_t cmd __attribute__ ((unused)),
                          int argc, char **args)
 {
   (void) GRUB_FIELD_MATCH (grub_term_outputs, struct abstract_terminal *, next);
+  (void) GRUB_FIELD_MATCH (grub_term_outputs, struct abstract_terminal *, prev);
   (void) GRUB_FIELD_MATCH (grub_term_outputs, struct abstract_terminal *, name);
   (void) GRUB_FIELD_MATCH (grub_term_outputs, struct abstract_terminal *, init);
   (void) GRUB_FIELD_MATCH (grub_term_outputs, struct abstract_terminal *, fini);
diff --git a/grub-core/disk/ahci.c b/grub-core/disk/ahci.c
index 10b7be687..a5a14d414 100644
--- a/grub-core/disk/ahci.c
+++ b/grub-core/disk/ahci.c
@@ -121,6 +121,7 @@ enum
 struct grub_ahci_device
 {
   struct grub_ahci_device *next;
+  struct grub_ahci_device **prev;
   volatile struct grub_ahci_hba *hba;
   int port;
   int num;
diff --git a/grub-core/gettext/gettext.c b/grub-core/gettext/gettext.c
index 682754421..2ff9d079b 100644
--- a/grub-core/gettext/gettext.c
+++ b/grub-core/gettext/gettext.c
@@ -46,6 +46,7 @@ static const char *(*grub_gettext_original) (const char *s);
 struct grub_gettext_msg
 {
   struct grub_gettext_msg *next;
+  struct grub_gettext_msg *prev;
   const char *name;
 
   const char *translated;
diff --git a/grub-core/kern/command.c b/grub-core/kern/command.c
index 7f353b653..91e469181 100644
--- a/grub-core/kern/command.c
+++ b/grub-core/kern/command.c
@@ -52,7 +52,6 @@ grub_register_command_prio (const char *name,
 void
 grub_unregister_command (grub_command_t cmd)
 {
-  grub_prio_list_remove (GRUB_AS_PRIO_LIST_P (&grub_command_list),
-			 GRUB_AS_PRIO_LIST (cmd));
+  grub_prio_list_remove (GRUB_AS_PRIO_LIST (cmd));
   grub_free (cmd);
 }
diff --git a/grub-core/kern/emu/hostdisk.c b/grub-core/kern/emu/hostdisk.c
index b3d35dd43..81e601f0b 100644
--- a/grub-core/kern/emu/hostdisk.c
+++ b/grub-core/kern/emu/hostdisk.c
@@ -635,6 +635,7 @@ devmapper_fail:
 struct linux_partition_cache
 {
   struct linux_partition_cache *next;
+  struct linux_partition_cache **prev;
   char *dev;
   unsigned long start;
   int partno;
diff --git a/grub-core/kern/list.c b/grub-core/kern/list.c
index 33c334166..f7c4e6bbe 100644
--- a/grub-core/kern/list.c
+++ b/grub-core/kern/list.c
@@ -21,26 +21,6 @@
 #include <grub/misc.h>
 #include <grub/mm.h>
 
-void
-grub_list_push (grub_list_t *head, grub_list_t item)
-{
-  item->next = *head;
-  *head = item;
-}
-
-void
-grub_list_remove (grub_list_t *head, grub_list_t item)
-{
-  grub_list_t *p, q;
-
-  for (p = head, q = *p; q; p = &(q->next), q = q->next)
-    if (q == item)
-      {
-	*p = q->next;
-	break;
-      }
-}
-
 void *
 grub_named_list_find (grub_named_list_t head, const char *name)
 {
@@ -81,6 +61,9 @@ grub_prio_list_insert (grub_prio_list_t *head, grub_prio_list_t nitem)
 
   *p = nitem;
   nitem->next = q;
+  if (q)
+    q->prev = &nitem->next;
+  nitem->prev = p;
 
   if (! inactive)
     nitem->prio |= GRUB_PRIO_LIST_FLAG_ACTIVE;
diff --git a/grub-core/loader/i386/xnu.c b/grub-core/loader/i386/xnu.c
index 98b635911..ac562a20d 100644
--- a/grub-core/loader/i386/xnu.c
+++ b/grub-core/loader/i386/xnu.c
@@ -58,6 +58,7 @@ static struct tbl_alias table_aliases[] =
 struct grub_xnu_devprop_device_descriptor
 {
   struct grub_xnu_devprop_device_descriptor *next;
+  struct grub_xnu_devprop_device_descriptor **prev;
   struct property_descriptor *properties;
   struct grub_efi_device_path *path;
   int pathlen;
@@ -212,6 +213,7 @@ guessfsb (void)
 struct property_descriptor
 {
   struct property_descriptor *next;
+  struct property_descriptor **prev;
   grub_uint8_t *name;
   grub_uint16_t *name16;
   int name16len;
@@ -234,7 +236,7 @@ grub_xnu_devprop_remove_property (struct grub_xnu_devprop_device_descriptor *dev
   grub_free (prop->name16);
   grub_free (prop->data);
 
-  grub_list_remove (GRUB_AS_LIST_P (&dev->properties), GRUB_AS_LIST (prop));
+  grub_list_remove (GRUB_AS_LIST (prop));
 
   return GRUB_ERR_NONE;
 }
@@ -245,7 +247,7 @@ grub_xnu_devprop_remove_device (struct grub_xnu_devprop_device_descriptor *dev)
   void *t;
   struct property_descriptor *prop;
 
-  grub_list_remove (GRUB_AS_LIST_P (&devices), GRUB_AS_LIST (dev));
+  grub_list_remove (GRUB_AS_LIST (dev));
 
   for (prop = dev->properties; prop; )
     {
diff --git a/grub-core/net/net.c b/grub-core/net/net.c
index 347a95afd..25d079b94 100644
--- a/grub-core/net/net.c
+++ b/grub-core/net/net.c
@@ -40,6 +40,7 @@ char *grub_net_default_server;
 struct grub_net_route
 {
   struct grub_net_route *next;
+  struct grub_net_route **prev;
   grub_net_network_level_netaddress_t target;
   char *name;
   struct grub_net_network_level_protocol *prot;
@@ -206,8 +207,7 @@ grub_net_card_unregister (struct grub_net_card *card)
 	card->driver->close (card);
       card->opened = 0;
     }
-  grub_list_remove (GRUB_AS_LIST_P (&grub_net_cards),
-		    GRUB_AS_LIST (card));
+  grub_list_remove (GRUB_AS_LIST (card));
 }
 
 static struct grub_net_slaac_mac_list *
@@ -366,8 +366,7 @@ grub_net_route_register (struct grub_net_route *route)
 static inline void
 grub_net_route_unregister (struct grub_net_route *route)
 {
-  grub_list_remove (GRUB_AS_LIST_P (&grub_net_routes),
-		    GRUB_AS_LIST (route));
+  grub_list_remove (GRUB_AS_LIST (route));
 }
 
 #define FOR_NET_ROUTES(var) for (var = grub_net_routes; var; var = var->next)
diff --git a/grub-core/net/tcp.c b/grub-core/net/tcp.c
index 1201220b5..65c6869c8 100644
--- a/grub-core/net/tcp.c
+++ b/grub-core/net/tcp.c
@@ -31,6 +31,7 @@
 struct unacked
 {
   struct unacked *next;
+  struct unacked **prev;
   struct grub_net_buff *nb;
   grub_uint64_t last_try;
   int try_count;
@@ -49,6 +50,7 @@ enum
 struct grub_net_tcp_socket
 {
   struct grub_net_tcp_socket *next;
+  struct grub_net_tcp_socket **prev;
 
   int established;
   int i_closed;
@@ -80,6 +82,7 @@ struct grub_net_tcp_socket
 struct grub_net_tcp_listen
 {
   struct grub_net_tcp_listen *next;
+  struct grub_net_tcp_listen **prev;
 
   grub_uint16_t port;
   const struct grub_net_network_level_interface *inf;
@@ -149,8 +152,7 @@ grub_net_tcp_listen (grub_uint16_t port,
 void
 grub_net_tcp_stop_listen (grub_net_tcp_listen_t listen)
 {
-  grub_list_remove (GRUB_AS_LIST_P (&tcp_listens),
-		    GRUB_AS_LIST (listen));
+  grub_list_remove (GRUB_AS_LIST (listen));
 }
 
 static inline void
@@ -640,8 +642,7 @@ grub_net_tcp_open (char *server,
 				     GRUB_NET_IP_TCP);
       if (err)
 	{
-	  grub_list_remove (GRUB_AS_LIST_P (&tcp_sockets),
-			    GRUB_AS_LIST (socket));
+	  grub_list_remove (GRUB_AS_LIST (socket));
 	  grub_free (socket);
 	  grub_netbuff_free (nb);
 	  return NULL;
@@ -654,8 +655,7 @@ grub_net_tcp_open (char *server,
     }
   if (!socket->established)
     {
-      grub_list_remove (GRUB_AS_LIST_P (&tcp_sockets),
-			GRUB_AS_LIST (socket));
+      grub_list_remove (GRUB_AS_LIST (socket));
       if (socket->they_reseted)
 	grub_error (GRUB_ERR_NET_PORT_CLOSED, "port closed");
       else
diff --git a/grub-core/net/udp.c b/grub-core/net/udp.c
index 8ca8ebb0a..afe5de0c9 100644
--- a/grub-core/net/udp.c
+++ b/grub-core/net/udp.c
@@ -25,6 +25,7 @@
 struct grub_net_udp_socket
 {
   struct grub_net_udp_socket *next;
+  struct grub_net_udp_socket **prev;
 
   enum { GRUB_NET_SOCKET_START,
 	 GRUB_NET_SOCKET_ESTABLISHED,
@@ -53,8 +54,7 @@ udp_socket_register (grub_net_udp_socket_t sock)
 void
 grub_net_udp_close (grub_net_udp_socket_t sock)
 {
-  grub_list_remove (GRUB_AS_LIST_P (&udp_sockets),
-		    GRUB_AS_LIST (sock));
+  grub_list_remove (GRUB_AS_LIST (sock));
   grub_free (sock);
 }
 
diff --git a/grub-core/normal/auth.c b/grub-core/normal/auth.c
index 8e19568e2..499eb6c9d 100644
--- a/grub-core/normal/auth.c
+++ b/grub-core/normal/auth.c
@@ -28,6 +28,7 @@
 struct grub_auth_user
 {
   struct grub_auth_user *next;
+  struct grub_auth_user **prev;
   char *name;
   grub_auth_callback_t callback;
   void *arg;
@@ -73,7 +74,7 @@ grub_auth_unregister_authentication (const char *user)
   if (!cur->authenticated)
     {
       grub_free (cur->name);
-      grub_list_remove (GRUB_AS_LIST_P (&users), GRUB_AS_LIST (cur));
+      grub_list_remove (GRUB_AS_LIST (cur));
       grub_free (cur);
     }
   else
@@ -121,7 +122,7 @@ grub_auth_deauthenticate (const char *user)
   if (!cur->callback)
     {
       grub_free (cur->name);
-      grub_list_remove (GRUB_AS_LIST_P (&users), GRUB_AS_LIST (cur));
+      grub_list_remove (GRUB_AS_LIST (cur));
       grub_free (cur);
     }
   else
diff --git a/grub-core/term/serial.c b/grub-core/term/serial.c
index 7b970587f..20ab90d92 100644
--- a/grub-core/term/serial.c
+++ b/grub-core/term/serial.c
@@ -350,7 +350,7 @@ grub_serial_unregister (struct grub_serial_port *port)
   if (port->term_out)
     grub_term_unregister_output (port->term_out);
 
-  grub_list_remove (GRUB_AS_LIST_P (&grub_serial_ports), GRUB_AS_LIST (port));
+  grub_list_remove (GRUB_AS_LIST (port));
 }
 
 void
diff --git a/grub-core/tests/lib/test.c b/grub-core/tests/lib/test.c
index 06d78b7d7..da688efc0 100644
--- a/grub-core/tests/lib/test.c
+++ b/grub-core/tests/lib/test.c
@@ -24,6 +24,7 @@ struct grub_test_failure
 {
   /* The next failure.  */
   struct grub_test_failure *next;
+  struct grub_test_failure **prev;
 
   /* The test source file name.  */
   char *file;
@@ -124,7 +125,7 @@ grub_test_unregister (const char *name)
 
   if (test)
     {
-      grub_list_remove (GRUB_AS_LIST_P (&grub_test_list), GRUB_AS_LIST (test));
+      grub_list_remove (GRUB_AS_LIST (test));
 
       if (test->name)
 	grub_free (test->name);
diff --git a/include/grub/command.h b/include/grub/command.h
index 19622752e..57c06da46 100644
--- a/include/grub/command.h
+++ b/include/grub/command.h
@@ -49,6 +49,7 @@ struct grub_command
 {
   /* The next element.  */
   struct grub_command *next;
+  struct grub_command **prev;
 
   /* The name.  */
   const char *name;
diff --git a/include/grub/cryptodisk.h b/include/grub/cryptodisk.h
index c6d1ce8de..0bb5d444e 100644
--- a/include/grub/cryptodisk.h
+++ b/include/grub/cryptodisk.h
@@ -59,6 +59,7 @@ typedef gcry_err_code_t
 struct grub_cryptodisk
 {
   struct grub_cryptodisk *next;
+  struct grub_cryptodisk **prev;
 
   char *source;
   grub_disk_addr_t offset;
@@ -96,6 +97,7 @@ typedef struct grub_cryptodisk *grub_cryptodisk_t;
 struct grub_cryptodisk_dev
 {
   struct grub_cryptodisk_dev *next;
+  struct grub_cryptodisk_dev **prev;
 
   grub_cryptodisk_t (*scan) (grub_disk_t disk, const char *check_uuid,
 			     int boot_only);
@@ -116,7 +118,7 @@ grub_cryptodisk_dev_register (grub_cryptodisk_dev_t cr)
 static inline void
 grub_cryptodisk_dev_unregister (grub_cryptodisk_dev_t cr)
 {
-  grub_list_remove (GRUB_AS_LIST_P (&grub_cryptodisk_list), GRUB_AS_LIST (cr));
+  grub_list_remove (GRUB_AS_LIST (cr));
 }
 
 #define FOR_CRYPTODISK_DEVS(var) FOR_LIST_ELEMENTS((var), (grub_cryptodisk_list))
diff --git a/include/grub/fs.h b/include/grub/fs.h
index dd274e151..10374ed90 100644
--- a/include/grub/fs.h
+++ b/include/grub/fs.h
@@ -46,6 +46,7 @@ struct grub_fs
 {
   /* The next filesystem.  */
   struct grub_fs *next;
+  struct grub_fs **prev;
 
   /* My name.  */
   const char *name;
@@ -111,7 +112,7 @@ grub_fs_register (grub_fs_t fs)
 static inline void
 grub_fs_unregister (grub_fs_t fs)
 {
-  grub_list_remove (GRUB_AS_LIST_P (&grub_fs_list), GRUB_AS_LIST (fs));
+  grub_list_remove (GRUB_AS_LIST (fs));
 }
 
 #define FOR_FILESYSTEMS(var) FOR_LIST_ELEMENTS((var), (grub_fs_list))
diff --git a/include/grub/list.h b/include/grub/list.h
index 3dfb97ac6..6629b2c19 100644
--- a/include/grub/list.h
+++ b/include/grub/list.h
@@ -27,11 +27,27 @@
 struct grub_list
 {
   struct grub_list *next;
+  struct grub_list **prev;
 };
 typedef struct grub_list *grub_list_t;
 
-void EXPORT_FUNC(grub_list_push) (grub_list_t *head, grub_list_t item);
-void EXPORT_FUNC(grub_list_remove) (grub_list_t *head, grub_list_t item);
+static inline void
+grub_list_push (grub_list_t *head, grub_list_t item)
+{
+  item->prev = head;
+  if (*head)
+    (*head)->prev = &item->next;
+  item->next = *head;
+  *head = item;
+}
+
+static inline void
+grub_list_remove (grub_list_t item)
+{
+  *item->prev = item->next;
+  if (item->next)
+    item->next->prev = item->prev;
+}
 
 #define FOR_LIST_ELEMENTS(var, list) for ((var) = (list); (var); (var) = (var)->next)
 
@@ -53,16 +69,17 @@ grub_bad_type_cast_real (int line, const char *file)
   ((char *) &(ptr)->field == (char *) &((type) (ptr))->field)
 
 #define GRUB_AS_LIST(ptr) \
-  (GRUB_FIELD_MATCH (ptr, grub_list_t, next) ? \
+  (GRUB_FIELD_MATCH (ptr, grub_list_t, next) && GRUB_FIELD_MATCH (ptr, grub_list_t, prev) ? \
    (grub_list_t) ptr : (grub_list_t) grub_bad_type_cast ())
 
 #define GRUB_AS_LIST_P(pptr) \
-  (GRUB_FIELD_MATCH (*pptr, grub_list_t, next) ? \
+  (GRUB_FIELD_MATCH (*pptr, grub_list_t, next) && GRUB_FIELD_MATCH (*pptr, grub_list_t, prev) ? \
    (grub_list_t *) (void *) pptr : (grub_list_t *) grub_bad_type_cast ())
 
 struct grub_named_list
 {
   struct grub_named_list *next;
+  struct grub_named_list **prev;
   char *name;
 };
 typedef struct grub_named_list *grub_named_list_t;
@@ -71,13 +88,15 @@ void * EXPORT_FUNC(grub_named_list_find) (grub_named_list_t head,
 					  const char *name);
 
 #define GRUB_AS_NAMED_LIST(ptr) \
-  ((GRUB_FIELD_MATCH (ptr, grub_named_list_t, next) && \
-    GRUB_FIELD_MATCH (ptr, grub_named_list_t, name))? \
+  ((GRUB_FIELD_MATCH (ptr, grub_named_list_t, next) \
+    && GRUB_FIELD_MATCH (ptr, grub_named_list_t, prev)	\
+    && GRUB_FIELD_MATCH (ptr, grub_named_list_t, name))? \
    (grub_named_list_t) ptr : (grub_named_list_t) grub_bad_type_cast ())
 
 #define GRUB_AS_NAMED_LIST_P(pptr) \
-  ((GRUB_FIELD_MATCH (*pptr, grub_named_list_t, next) && \
-    GRUB_FIELD_MATCH (*pptr, grub_named_list_t, name))? \
+  ((GRUB_FIELD_MATCH (*pptr, grub_named_list_t, next) \
+    && GRUB_FIELD_MATCH (*pptr, grub_named_list_t, prev)   \
+    && GRUB_FIELD_MATCH (*pptr, grub_named_list_t, name))? \
    (grub_named_list_t *) (void *) pptr : (grub_named_list_t *) grub_bad_type_cast ())
 
 #define GRUB_PRIO_LIST_PRIO_MASK	0xff
@@ -86,6 +105,7 @@ void * EXPORT_FUNC(grub_named_list_find) (grub_named_list_t head,
 struct grub_prio_list
 {
   struct grub_prio_list *next;
+  struct grub_prio_list **prev;
   char *name;
   int prio;
 };
@@ -95,24 +115,26 @@ void EXPORT_FUNC(grub_prio_list_insert) (grub_prio_list_t *head,
 					 grub_prio_list_t item);
 
 static inline void
-grub_prio_list_remove (grub_prio_list_t *head, grub_prio_list_t item)
+grub_prio_list_remove (grub_prio_list_t item)
 {
   if ((item->prio & GRUB_PRIO_LIST_FLAG_ACTIVE) && (item->next))
     item->next->prio |= GRUB_PRIO_LIST_FLAG_ACTIVE;
-  grub_list_remove (GRUB_AS_LIST_P (head), GRUB_AS_LIST (item));
+  grub_list_remove (GRUB_AS_LIST (item));
 }
 
 #define GRUB_AS_PRIO_LIST(ptr) \
-  ((GRUB_FIELD_MATCH (ptr, grub_prio_list_t, next) && \
-    GRUB_FIELD_MATCH (ptr, grub_prio_list_t, name) && \
-    GRUB_FIELD_MATCH (ptr, grub_prio_list_t, prio))? \
+  ((GRUB_FIELD_MATCH (ptr, grub_prio_list_t, next)  \
+    && GRUB_FIELD_MATCH (ptr, grub_prio_list_t, prev) \
+    && GRUB_FIELD_MATCH (ptr, grub_prio_list_t, name) \
+    && GRUB_FIELD_MATCH (ptr, grub_prio_list_t, prio))? \
    (grub_prio_list_t) ptr \
    : (grub_prio_list_t) grub_bad_type_cast ())
 
 #define GRUB_AS_PRIO_LIST_P(pptr) \
-  ((GRUB_FIELD_MATCH (*pptr, grub_prio_list_t, next) && \
-    GRUB_FIELD_MATCH (*pptr, grub_prio_list_t, name) && \
-    GRUB_FIELD_MATCH (*pptr, grub_prio_list_t, prio)) ? \
+  ((GRUB_FIELD_MATCH (*pptr, grub_prio_list_t, next) \
+    && GRUB_FIELD_MATCH (*pptr, grub_prio_list_t, prev) \
+    && GRUB_FIELD_MATCH (*pptr, grub_prio_list_t, name) \
+    && GRUB_FIELD_MATCH (*pptr, grub_prio_list_t, prio)) ? \
    (grub_prio_list_t *) (void *) pptr \
    : (grub_prio_list_t *) grub_bad_type_cast ())
 
diff --git a/include/grub/net.h b/include/grub/net.h
index 3913272eb..d9fd821d9 100644
--- a/include/grub/net.h
+++ b/include/grub/net.h
@@ -72,6 +72,7 @@ struct grub_net_card;
 struct grub_net_card_driver
 {
   struct grub_net_card_driver *next;
+  struct grub_net_card_driver **prev;
   const char *name;
   grub_err_t (*open) (const struct grub_net_card *dev);
   void (*close) (const struct grub_net_card *dev);
@@ -101,6 +102,7 @@ typedef struct grub_net_packets
 struct grub_net_slaac_mac_list
 {
   struct grub_net_slaac_mac_list *next;
+  struct grub_net_slaac_mac_list **prev;
   grub_net_link_level_address_t address;
   int slaac_counter;
   char *name;
@@ -111,6 +113,7 @@ struct grub_net_link_layer_entry;
 struct grub_net_card
 {
   struct grub_net_card *next;
+  struct grub_net_card **prev;
   const char *name;
   struct grub_net_card_driver *driver;
   grub_net_link_level_address_t default_address;
@@ -220,6 +223,7 @@ typedef struct grub_net_socket *grub_net_socket_t;
 struct grub_net_app_protocol 
 {
   struct grub_net_app_protocol *next;
+  struct grub_net_app_protocol **prev;
   const char *name;
   grub_err_t (*dir) (grub_device_t device, const char *path,
 		     int (*hook) (const char *filename,
@@ -317,8 +321,7 @@ grub_net_app_level_register (grub_net_app_level_t proto)
 static inline void
 grub_net_app_level_unregister (grub_net_app_level_t proto)
 {
-  grub_list_remove (GRUB_AS_LIST_P (&grub_net_app_level_list),
-		    GRUB_AS_LIST (proto));
+  grub_list_remove (GRUB_AS_LIST (proto));
 }
 
 #define FOR_NET_APP_LEVEL(var) FOR_LIST_ELEMENTS((var), \
diff --git a/include/grub/partition.h b/include/grub/partition.h
index e7e00ef7f..7c1e7f6b3 100644
--- a/include/grub/partition.h
+++ b/include/grub/partition.h
@@ -38,6 +38,7 @@ struct grub_partition_map
 {
   /* The next partition map type.  */
   struct grub_partition_map *next;
+  struct grub_partition_map **prev;
 
   /* The name of the partition map type.  */
   const char *name;
@@ -106,8 +107,7 @@ grub_partition_map_register (grub_partition_map_t partmap)
 static inline void
 grub_partition_map_unregister (grub_partition_map_t partmap)
 {
-  grub_list_remove (GRUB_AS_LIST_P (&grub_partition_map_list),
-		    GRUB_AS_LIST (partmap));
+  grub_list_remove (GRUB_AS_LIST (partmap));
 }
 
 #define FOR_PARTITION_MAPS(var) FOR_LIST_ELEMENTS((var), (grub_partition_map_list))
diff --git a/include/grub/serial.h b/include/grub/serial.h
index feaa5b1a7..242823fab 100644
--- a/include/grub/serial.h
+++ b/include/grub/serial.h
@@ -63,6 +63,7 @@ struct grub_serial_config
 struct grub_serial_port
 {
   struct grub_serial_port *next;
+  struct grub_serial_port **prev;
   char *name;
   struct grub_serial_driver *driver;
   struct grub_serial_config config;
diff --git a/include/grub/term.h b/include/grub/term.h
index 4c997cdaf..8fdf16234 100644
--- a/include/grub/term.h
+++ b/include/grub/term.h
@@ -147,6 +147,7 @@ struct grub_term_input
 {
   /* The next terminal.  */
   struct grub_term_input *next;
+  struct grub_term_input **prev;
 
   /* The terminal name.  */
   const char *name;
@@ -171,6 +172,7 @@ struct grub_term_output
 {
   /* The next terminal.  */
   struct grub_term_output *next;
+  struct grub_term_output **prev;
 
   /* The terminal name.  */
   const char *name;
@@ -300,17 +302,15 @@ grub_term_register_output_active (const char *name __attribute__ ((unused)),
 static inline void
 grub_term_unregister_input (grub_term_input_t term)
 {
-  grub_list_remove (GRUB_AS_LIST_P (&grub_term_inputs), GRUB_AS_LIST (term));
-  grub_list_remove (GRUB_AS_LIST_P (&grub_term_inputs_disabled),
-		    GRUB_AS_LIST (term));
+  grub_list_remove (GRUB_AS_LIST (term));
+  grub_list_remove (GRUB_AS_LIST (term));
 }
 
 static inline void
 grub_term_unregister_output (grub_term_output_t term)
 {
-  grub_list_remove (GRUB_AS_LIST_P (&grub_term_outputs), GRUB_AS_LIST (term));
-  grub_list_remove (GRUB_AS_LIST_P (&(grub_term_outputs_disabled)),
-		    GRUB_AS_LIST (term));
+  grub_list_remove (GRUB_AS_LIST (term));
+  grub_list_remove (GRUB_AS_LIST (term));
 }
 
 #define FOR_ACTIVE_TERM_INPUTS(var) FOR_LIST_ELEMENTS((var), (grub_term_inputs))
diff --git a/include/grub/test.h b/include/grub/test.h
index 336d3b672..04a8ca13a 100644
--- a/include/grub/test.h
+++ b/include/grub/test.h
@@ -29,6 +29,7 @@ struct grub_test
 {
   /* The next test.  */
   struct grub_test *next;
+  struct grub_test **prev;
 
   /* The test name.  */
   char *name;
diff --git a/include/grub/usb.h b/include/grub/usb.h
index ee133dbf5..bf6e101c8 100644
--- a/include/grub/usb.h
+++ b/include/grub/usb.h
@@ -264,6 +264,7 @@ typedef int (*grub_usb_attach_hook_class) (grub_usb_device_t usbdev,
 struct grub_usb_attach_desc
 {
   struct grub_usb_attach_desc *next;
+  struct grub_usb_attach_desc **prev;
   int class;
   grub_usb_attach_hook_class hook;
 };
diff --git a/include/grub/video.h b/include/grub/video.h
index 352544c85..b3709bceb 100644
--- a/include/grub/video.h
+++ b/include/grub/video.h
@@ -298,6 +298,7 @@ struct grub_video_adapter
 {
   /* The next video adapter.  */
   struct grub_video_adapter *next;
+  struct grub_video_adapter **prev;
 
   /* The video adapter name.  */
   const char *name;
@@ -398,8 +399,7 @@ grub_video_register (grub_video_adapter_t adapter)
 static inline void
 grub_video_unregister (grub_video_adapter_t adapter)
 {
-  grub_list_remove (GRUB_AS_LIST_P (&grub_video_adapter_list),
-		    GRUB_AS_LIST (adapter));
+  grub_list_remove (GRUB_AS_LIST (adapter));
 }
 
 #define FOR_VIDEO_ADAPTERS(var) FOR_LIST_ELEMENTS((var), (grub_video_adapter_list))
diff --git a/util/deviceiter.c b/util/deviceiter.c
index 208dcfdde..87cbc9ebc 100644
--- a/util/deviceiter.c
+++ b/util/deviceiter.c
@@ -369,6 +369,7 @@ get_xvd_disk_name (char *name, int unit)
 static struct seen_device
 {
   struct seen_device *next;
+  struct seen_device **prev;
   const char *name;
 } *seen;