1 files changed, 98 insertions, 0 deletions
diff --git a/contrib/syslinux-4.02/gpxe/src/interface/efi/efi_umalloc.c b/contrib/syslinux-4.02/gpxe/src/interface/efi/efi_umalloc.c
new file mode 100644
index 0000000..7113c79
--- /dev/null
+++ b/contrib/syslinux-4.02/gpxe/src/interface/efi/efi_umalloc.c
@@ -0,0 +1,98 @@
+/*
+ * Copyright (C) 2008 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * 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 of the
+ * License, or 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.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+#include <assert.h>
+#include <gpxe/umalloc.h>
+#include <gpxe/efi/efi.h>
+
+/** @file
+ *
+ * gPXE user memory allocation API for EFI
+ *
+ */
+
+/** Equivalent of NOWHERE for user pointers */
+#define UNOWHERE ( ~UNULL )
+
+/**
+ * Reallocate external memory
+ *
+ * @v old_ptr		Memory previously allocated by umalloc(), or UNULL
+ * @v new_size		Requested size
+ * @ret new_ptr		Allocated memory, or UNULL
+ *
+ * Calling realloc() with a new size of zero is a valid way to free a
+ * memory block.
+ */
+static userptr_t efi_urealloc ( userptr_t old_ptr, size_t new_size ) {
+	EFI_BOOT_SERVICES *bs = efi_systab->BootServices;
+	EFI_PHYSICAL_ADDRESS phys_addr;
+	unsigned int new_pages, old_pages;
+	userptr_t new_ptr = UNOWHERE;
+	size_t old_size;
+	EFI_STATUS efirc;
+
+	/* Allocate new memory if necessary.  If allocation fails,
+	 * return without touching the old block.
+	 */
+	if ( new_size ) {
+		new_pages = ( EFI_SIZE_TO_PAGES ( new_size ) + 1 );
+		if ( ( efirc = bs->AllocatePages ( AllocateAnyPages,
+						   EfiBootServicesData,
+						   new_pages,
+						   &phys_addr ) ) != 0 ) {
+			DBG ( "EFI could not allocate %d pages: %s\n",
+			      new_pages, efi_strerror ( efirc ) );
+			return UNULL;
+		}
+		assert ( phys_addr != 0 );
+		new_ptr = phys_to_user ( phys_addr + EFI_PAGE_SIZE );
+		copy_to_user ( new_ptr, -EFI_PAGE_SIZE,
+			       &new_size, sizeof ( new_size ) );
+		DBG ( "EFI allocated %d pages at %llx\n",
+		      new_pages, phys_addr );
+	}
+
+	/* Copy across relevant part of the old data region (if any),
+	 * then free it.  Note that at this point either (a) new_ptr
+	 * is valid, or (b) new_size is 0; either way, the memcpy() is
+	 * valid.
+	 */
+	if ( old_ptr && ( old_ptr != UNOWHERE ) ) {
+		copy_from_user ( &old_size, old_ptr, -EFI_PAGE_SIZE,
+				 sizeof ( old_size ) );
+		memcpy_user ( new_ptr, 0, old_ptr, 0,
+			      ( (old_size < new_size) ? old_size : new_size ));
+		old_pages = ( EFI_SIZE_TO_PAGES ( old_size ) + 1 );
+		phys_addr = user_to_phys ( old_ptr, -EFI_PAGE_SIZE );
+		if ( ( efirc = bs->FreePages ( phys_addr, old_pages ) ) != 0 ){
+			DBG ( "EFI could not free %d pages at %llx: %s\n",
+			      old_pages, phys_addr, efi_strerror ( efirc ) );
+			/* Not fatal; we have leaked memory but successfully
+			 * allocated (if asked to do so).
+			 */
+		}
+		DBG ( "EFI freed %d pages at %llx\n", old_pages, phys_addr );
+	}
+
+	return new_ptr;
+}
+
+PROVIDE_UMALLOC ( efi, urealloc, efi_urealloc );