The self-relocation code is not efi-specific, move it to boot/common.

The function was defined as taking 4 parameters and returning EFI_STATUS,
but all existing callers (in asm code) passed only two parameters and don't
use the return value. The function signature now matches that usage, and
doesn't refer to efi-specific types.

Parameters and variables now use the cannonical typenames set up by elf.h
(Elf_Word, Elf_Addr, etc) instead of raw C types. Hopefully this will
prevent suprises as new platforms come along and use this code.

The function was renamed from _reloc() to self_reloc() to emphasize its
difference from the other elf relocation code found in boot/common.

Differential Revision:	https://reviews.freebsd.org/D2490

1 files changed, 123 insertions, 0 deletions

diff --git a/sys/boot/common/self_reloc.c b/sys/boot/common/self_reloc.c
new file mode 100644
index 0000000..9864a48
--- /dev/null
+++ b/sys/boot/common/self_reloc.c
@@ -0,0 +1,123 @@
+/*-
+ * Copyright (c) 2008-2010 Rui Paulo <rpaulo@FreeBSD.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/types.h>
+#include <elf.h>
+#include <bootstrap.h>
+
+#if defined(__aarch64__)
+#define	ElfW_Rel	Elf64_Rela
+#define	ElfW_Dyn	Elf64_Dyn
+#define	ELFW_R_TYPE	ELF64_R_TYPE
+#define	ELF_RELA
+#elif defined(__arm__) || defined(__i386__)
+#define	ElfW_Rel	Elf32_Rel
+#define	ElfW_Dyn	Elf32_Dyn
+#define	ELFW_R_TYPE	ELF32_R_TYPE
+#elif defined(__amd64__)
+#define	ElfW_Rel	Elf64_Rel
+#define	ElfW_Dyn	Elf64_Dyn
+#define	ELFW_R_TYPE	ELF64_R_TYPE
+#else
+#error architecture not supported
+#endif
+#if defined(__aarch64__)
+#define	RELOC_TYPE_NONE		R_AARCH64_NONE
+#define	RELOC_TYPE_RELATIVE	R_AARCH64_RELATIVE
+#elif defined(__amd64__)
+#define	RELOC_TYPE_NONE		R_X86_64_NONE
+#define	RELOC_TYPE_RELATIVE	R_X86_64_RELATIVE
+#elif defined(__arm__)
+#define	RELOC_TYPE_NONE		R_ARM_NONE
+#define	RELOC_TYPE_RELATIVE	R_ARM_RELATIVE
+#elif defined(__i386__)
+#define	RELOC_TYPE_NONE		R_386_NONE
+#define	RELOC_TYPE_RELATIVE	R_386_RELATIVE
+#endif
+
+/*
+ * A simple elf relocator.
+ */
+void
+self_reloc(Elf_Addr baseaddr, ElfW_Dyn *dynamic)
+{
+	Elf_Word relsz, relent;
+	Elf_Addr *newaddr;
+	ElfW_Rel *rel;
+	ElfW_Dyn *dynp;
+
+	/*
+	 * Find the relocation address, its size and the relocation entry.
+	 */
+	relsz = 0;
+	relent = 0;
+	for (dynp = dynamic; dynp->d_tag != DT_NULL; dynp++) {
+		switch (dynp->d_tag) {
+		case DT_REL:
+		case DT_RELA:
+			rel = (ElfW_Rel *)(dynp->d_un.d_ptr + baseaddr);
+			break;
+		case DT_RELSZ:
+		case DT_RELASZ:
+			relsz = dynp->d_un.d_val;
+			break;
+		case DT_RELENT:
+		case DT_RELAENT:
+			relent = dynp->d_un.d_val;
+			break;
+		default:
+			break;
+		}
+	}
+
+	/*
+	 * Perform the actual relocation.
+	 */
+	for (; relsz > 0; relsz -= relent) {
+		switch (ELFW_R_TYPE(rel->r_info)) {
+		case RELOC_TYPE_NONE:
+			/* No relocation needs be performed. */
+			break;
+
+		case RELOC_TYPE_RELATIVE:
+			/* Address relative to the base address. */
+			newaddr = (Elf_Addr *)(rel->r_offset + baseaddr);
+			*newaddr += baseaddr;
+			/* Add the addend when the ABI uses them */ 
+#ifdef ELF_RELA
+			*newaddr += rel->r_addend;
+#endif
+			break;
+		default:
+			/* XXX: do we need other relocations ? */
+			break;
+		}
+		rel = (ElfW_Rel *) ((caddr_t) rel + relent);
+	}
+}