X-Git-Url: http://git.etherboot.org/gpxe.git/blobdiff_plain/fdc97499bf83ef958db8a50985fdd321835dccf3..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 70008a49..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>
@@ -23,6 +25,7 @@
 #include <realmode.h>
 #include <bios.h>
 #include <pnpbios.h>
+#include <basemem.h>
 #include <gpxe/pci.h>
 #include <undi.h>
 #include <undirom.h>
@@ -35,11 +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 )
 
 /**
@@ -51,11 +54,16 @@ static SEGOFF16_t __data16 ( undi_loader_entry );
  */
 int undi_load ( struct undi_device *undi, struct undi_rom *undirom ) {
 	struct s_PXE ppxe;
-	uint16_t fbms;
 	unsigned int fbms_seg;
 	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;
@@ -65,9 +73,8 @@ int undi_load ( struct undi_device *undi, struct undi_rom *undirom ) {
 	undi_loader.DI = find_pnp_bios();
 
 	/* Allocate base memory for PXE stack */
-	get_real ( fbms, BDA_SEG, BDA_FBMS );
-	undi->restore_fbms = fbms;
-	fbms_seg = ( fbms << 6 );
+	undi->restore_fbms = get_fbms();
+	fbms_seg = ( undi->restore_fbms << 6 );
 	fbms_seg -= ( ( undirom->code_size + 0x0f ) >> 4 );
 	undi_loader.UNDI_CS = fbms_seg;
 	fbms_seg -= ( ( undirom->data_size + 0x0f ) >> 4 );
@@ -91,24 +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;
@@ -129,9 +128,8 @@ int undi_load ( struct undi_device *undi, struct undi_rom *undirom ) {
 	       undi->entry.segment, undi->entry.offset );
 
 	/* Update free base memory counter */
-	fbms = ( fbms_seg >> 6 );
-	put_real ( fbms, BDA_SEG, BDA_FBMS );
-	undi->fbms = fbms;
+	undi->fbms = ( fbms_seg >> 6 );
+	set_fbms ( undi->fbms );
 	DBGC ( undi, "UNDI %p using [%d,%d) kB of base memory\n",
 	       undi, undi->fbms, undi->restore_fbms );
 
@@ -149,10 +147,12 @@ int undi_load ( struct undi_device *undi, struct undi_rom *undirom ) {
  */
 int undi_unload ( struct undi_device *undi ) {
 	static uint32_t dead = 0xdeaddead;
-	uint16_t fbms;
 
 	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 );
@@ -160,12 +160,10 @@ int undi_unload ( struct undi_device *undi ) {
 		put_real ( dead, undi->ppxe.segment, undi->ppxe.offset );
 
 	/* Free base memory, if possible */
-	get_real ( fbms, BDA_SEG, BDA_FBMS );
-	if ( fbms == undi->fbms ) {
+	if ( undi->fbms == get_fbms() ) {
 		DBGC ( undi, "UNDI %p freeing [%d,%d) kB of base memory\n",
 		       undi, undi->fbms, undi->restore_fbms );
-		fbms = undi->restore_fbms;
-		put_real ( fbms, BDA_SEG, BDA_FBMS );
+		set_fbms ( undi->restore_fbms );
 		return 0;
 	} else {
 		DBGC ( undi, "UNDI %p leaking [%d,%d) kB of base memory\n",