X-Git-Url: http://git.etherboot.org/gpxe.git/blobdiff_plain/80cc27cbc44cf6b692141840ab2ef7abf0a2c1a0..92b8f2fc2eb9c8571a5fad8b19113cb75a7c7877:/src/arch/i386/drivers/net/undiload.c

diff --git a/src/arch/i386/drivers/net/undiload.c b/src/arch/i386/drivers/net/undiload.c
index fc8d9194..8271b508 100644
--- a/src/arch/i386/drivers/net/undiload.c
+++ b/src/arch/i386/drivers/net/undiload.c
@@ -16,6 +16,8 @@
  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
+FILE_LICENCE ( GPL2_OR_LATER );
+
 #include <stdint.h>
 #include <stdlib.h>
 #include <string.h>
@@ -36,11 +38,11 @@
  */
 
 /** Parameter block for calling UNDI loader */
-static struct s_UNDI_LOADER __data16 ( undi_loader );
+static struct s_UNDI_LOADER __bss16 ( undi_loader );
 #define undi_loader __use_data16 ( undi_loader )
 
 /** UNDI loader entry point */
-static SEGOFF16_t __data16 ( undi_loader_entry );
+static SEGOFF16_t __bss16 ( undi_loader_entry );
 #define undi_loader_entry __use_data16 ( undi_loader_entry )
 
 /**
@@ -56,6 +58,12 @@ int undi_load ( struct undi_device *undi, struct undi_rom *undirom ) {
 	uint16_t exit;
 	int rc;
 
+	/* Only one UNDI instance may be loaded at any given time */
+	if ( undi_loader_entry.segment ) {
+		DBG ( "UNDI %p cannot load multiple instances\n", undi );
+		return -EBUSY;
+	}
+
 	/* Set up START_UNDI parameters */
 	memset ( &undi_loader, 0, sizeof ( undi_loader ) );
 	undi_loader.AX = undi->pci_busdevfn;
@@ -90,24 +98,16 @@ int undi_load ( struct undi_device *undi, struct undi_rom *undirom ) {
 	undi_loader_entry = undirom->loader_entry;
 	__asm__ __volatile__ ( REAL_CODE ( "pushw %%ds\n\t"
 					   "pushw %%ax\n\t"
-					   "lcall *%c2\n\t"
+					   "lcall *undi_loader_entry\n\t"
 					   "addw $4, %%sp\n\t" )
 			       : "=a" ( exit )
-			       : "a" ( & __from_data16 ( undi_loader ) ),
-			         "p" ( & __from_data16 ( undi_loader_entry ) )
+			       : "a" ( __from_data16 ( &undi_loader ) )
 			       : "ebx", "ecx", "edx", "esi", "edi", "ebp" );
 
-	/* UNDI API calls may rudely change the status of A20 and not
-	 * bother to restore it afterwards.  Intel is known to be
-	 * guilty of this.
-	 *
-	 * Note that we will return to this point even if A20 gets
-	 * screwed up by the UNDI driver, because Etherboot always
-	 * resides in an even megabyte of RAM.
-	 */	
-	gateA20_set();
-
 	if ( exit != PXENV_EXIT_SUCCESS ) {
+		/* Clear entry point */
+		memset ( &undi_loader_entry, 0, sizeof ( undi_loader_entry ) );
+
 		rc = -undi_loader.Status;
 		if ( rc == 0 ) /* Paranoia */
 			rc = -EIO;
@@ -150,6 +150,9 @@ int undi_unload ( struct undi_device *undi ) {
 
 	DBGC ( undi, "UNDI %p unloading\n", undi );
 
+	/* Clear entry point */
+	memset ( &undi_loader_entry, 0, sizeof ( undi_loader_entry ) );
+
 	/* Erase signatures */
 	if ( undi->pxenv.segment )
 		put_real ( dead, undi->pxenv.segment, undi->pxenv.offset );