[U-Boot] [RFC 1/1] efi_loader: in situ relocation

[Heinrich Schuchardt]

All code and data sections of PE images are already in the correct relative
location when loaded into memory. There is not need to copy them once
again.

Signed-off-by: Heinrich Schuchardt <xypron.glpk at gmx.de>
---
 lib/efi_loader/efi_image_loader.c | 64 ++++++-------------------------
 1 file changed, 11 insertions(+), 53 deletions(-)

diff --git a/lib/efi_loader/efi_image_loader.c b/lib/efi_loader/efi_image_loader.c
index fe66e7b9ffe..6146acc6b6f 100644
--- a/lib/efi_loader/efi_image_loader.c
+++ b/lib/efi_loader/efi_image_loader.c
@@ -2,7 +2,7 @@
 /*
  *  EFI image loader
  *
- *  based partly on wine code
+ *  based partly on Wine code
  *
  *  Copyright (c) 2016 Alexander Graf
  */
@@ -219,16 +219,12 @@ efi_status_t efi_load_pe(struct efi_loaded_image_obj *handle, void *efi,
 {
 	IMAGE_NT_HEADERS32 *nt;
 	IMAGE_DOS_HEADER *dos;
-	IMAGE_SECTION_HEADER *sections;
-	int num_sections;
-	void *efi_reloc;
 	int i;
 	const IMAGE_BASE_RELOCATION *rel;
 	unsigned long rel_size;
 	int rel_idx = IMAGE_DIRECTORY_ENTRY_BASERELOC;
 	uint64_t image_base;
 	uint64_t image_size;
-	unsigned long virt_size = 0;
 	int supported = 0;
 
 	dos = efi;
@@ -255,85 +251,47 @@ efi_status_t efi_load_pe(struct efi_loaded_image_obj *handle, void *efi,
 		return EFI_LOAD_ERROR;
 	}
 
-	/* Calculate upper virtual address boundary */
-	num_sections = nt->FileHeader.NumberOfSections;
-	sections = (void *)&nt->OptionalHeader +
-			    nt->FileHeader.SizeOfOptionalHeader;
-
-	for (i = num_sections - 1; i >= 0; i--) {
-		IMAGE_SECTION_HEADER *sec = &sections[i];
-		virt_size = max_t(unsigned long, virt_size,
-				  sec->VirtualAddress + sec->Misc.VirtualSize);
-	}
-
 	/* Read 32/64bit specific header bits */
 	if (nt->OptionalHeader.Magic == IMAGE_NT_OPTIONAL_HDR64_MAGIC) {
 		IMAGE_NT_HEADERS64 *nt64 = (void *)nt;
 		IMAGE_OPTIONAL_HEADER64 *opt = &nt64->OptionalHeader;
+
 		image_base = opt->ImageBase;
 		image_size = opt->SizeOfImage;
 		efi_set_code_and_data_type(loaded_image_info, opt->Subsystem);
-		efi_reloc = efi_alloc(virt_size,
-				      loaded_image_info->image_code_type);
-		if (!efi_reloc) {
-			printf("%s: Could not allocate %lu bytes\n",
-			       __func__, virt_size);
-			return EFI_OUT_OF_RESOURCES;
-		}
-		handle->entry = efi_reloc + opt->AddressOfEntryPoint;
+		handle->entry = efi + opt->AddressOfEntryPoint;
 		rel_size = opt->DataDirectory[rel_idx].Size;
-		rel = efi_reloc + opt->DataDirectory[rel_idx].VirtualAddress;
-		virt_size = ALIGN(virt_size, opt->SectionAlignment);
+		rel = efi + opt->DataDirectory[rel_idx].VirtualAddress;
 	} else if (nt->OptionalHeader.Magic == IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
 		IMAGE_OPTIONAL_HEADER32 *opt = &nt->OptionalHeader;
+
 		image_base = opt->ImageBase;
 		image_size = opt->SizeOfImage;
 		efi_set_code_and_data_type(loaded_image_info, opt->Subsystem);
-		efi_reloc = efi_alloc(virt_size,
-				      loaded_image_info->image_code_type);
-		if (!efi_reloc) {
-			printf("%s: Could not allocate %lu bytes\n",
-			       __func__, virt_size);
-			return EFI_OUT_OF_RESOURCES;
-		}
-		handle->entry = efi_reloc + opt->AddressOfEntryPoint;
+		handle->entry = efi + opt->AddressOfEntryPoint;
 		rel_size = opt->DataDirectory[rel_idx].Size;
-		rel = efi_reloc + opt->DataDirectory[rel_idx].VirtualAddress;
-		virt_size = ALIGN(virt_size, opt->SectionAlignment);
+		rel = efi + opt->DataDirectory[rel_idx].VirtualAddress;
 	} else {
 		printf("%s: Invalid optional header magic %x\n", __func__,
 		       nt->OptionalHeader.Magic);
 		return EFI_LOAD_ERROR;
 	}
 
-	/* Load sections into RAM */
-	for (i = num_sections - 1; i >= 0; i--) {
-		IMAGE_SECTION_HEADER *sec = &sections[i];
-		memset(efi_reloc + sec->VirtualAddress, 0,
-		       sec->Misc.VirtualSize);
-		memcpy(efi_reloc + sec->VirtualAddress,
-		       efi + sec->PointerToRawData,
-		       sec->SizeOfRawData);
-	}
-
 	/* Run through relocations */
-	if (efi_loader_relocate(rel, rel_size, efi_reloc,
+	if (efi_loader_relocate(rel, rel_size, efi,
 				(unsigned long)image_base) != EFI_SUCCESS) {
-		efi_free_pages((uintptr_t) efi_reloc,
-			       (virt_size + EFI_PAGE_MASK) >> EFI_PAGE_SHIFT);
 		return EFI_LOAD_ERROR;
 	}
 
 	/* Flush cache */
-	flush_cache((ulong)efi_reloc,
-		    ALIGN(virt_size, EFI_CACHELINE_SIZE));
+	flush_cache((ulong)efi, ALIGN(image_size, EFI_CACHELINE_SIZE));
 	invalidate_icache_all();
 
 	/* Populate the loaded image interface bits */
 	loaded_image_info->image_base = efi;
 	loaded_image_info->image_size = image_size;
-	handle->reloc_base = efi_reloc;
-	handle->reloc_size = virt_size;
+	handle->reloc_base = efi;
+	handle->reloc_size = image_size;
 
 	return EFI_SUCCESS;
 }
-- 
2.20.1