kpatch-elf: add kpatch_reindex_elements() and kpatch_rebuild_rela_section_data()

Move functions kpatch_reindex_elements() and kpatch_rebuild_rela_section_data()
from create-diff-object.c to kpatch-elf.c. These functions will be used
to rebuild kpatch elf data in create-klp-module and create-kpatch-module,
i.e. during the second "phase" of kpatch-build.

kpatch-build/create-diff-object.c

@@ -1311,26 +1311,6 @@ static void kpatch_reorder_symbols(struct kpatch_elf *kelf)
 	list_replace(&symbols, &kelf->symbols);
 }
 
-static void kpatch_reindex_elements(struct kpatch_elf *kelf)
-{
-	struct section *sec;
-	struct symbol *sym;
-	int index;
-
-	index = 1; /* elf write function handles NULL section 0 */
-	list_for_each_entry(sec, &kelf->sections, list)
-		sec->index = index++;
-
-	index = 0;
-	list_for_each_entry(sym, &kelf->symbols, list) {
-		sym->index = index++;
-		if (sym->sec)
-			sym->sym.st_shndx = sym->sec->index;
-		else if (sym->sym.st_shndx != SHN_ABS)
-			sym->sym.st_shndx = SHN_UNDEF;
-	}
-}
-
 static int bug_table_group_size(struct kpatch_elf *kelf, int offset)
 {
 	static int size = 0;
@@ -2265,38 +2245,6 @@ static void kpatch_build_strings_section_data(struct kpatch_elf *kelf)
 	}
 }
 
-static void kpatch_rebuild_rela_section_data(struct section *sec)
-{
-	struct rela *rela;
-	int nr = 0, index = 0, size;
-	GElf_Rela *relas;
-
-	list_for_each_entry(rela, &sec->relas, list)
-		nr++;
-
-	size = nr * sizeof(*relas);
-	relas = malloc(size);
-	if (!relas)
-		ERROR("malloc");
-
-	sec->data->d_buf = relas;
-	sec->data->d_size = size;
-	/* d_type remains ELF_T_RELA */
-
-	sec->sh.sh_size = size;
-
-	list_for_each_entry(rela, &sec->relas, list) {
-		relas[index].r_offset = rela->offset;
-		relas[index].r_addend = rela->addend;
-		relas[index].r_info = GELF_R_INFO(rela->sym->index, rela->type);
-		index++;
-	}
-
-	/* sanity check, index should equal nr */
-	if (index != nr)
-		ERROR("size mismatch in rebuilt rela section");
-}
-
 struct arguments {
 	char *args[4];
 	int debug;

kpatch-build/kpatch-elf.c

@@ -671,6 +671,58 @@ struct section *create_section_pair(struct kpatch_elf *kelf, char *name,
 	return sec;
 }
 
+void kpatch_reindex_elements(struct kpatch_elf *kelf)
+{
+	struct section *sec;
+	struct symbol *sym;
+	int index;
+
+	index = 1; /* elf write function handles NULL section 0 */
+	list_for_each_entry(sec, &kelf->sections, list)
+		sec->index = index++;
+
+	index = 0;
+	list_for_each_entry(sym, &kelf->symbols, list) {
+		sym->index = index++;
+		if (sym->sec)
+			sym->sym.st_shndx = sym->sec->index;
+		else if (sym->sym.st_shndx != SHN_ABS)
+			sym->sym.st_shndx = SHN_UNDEF;
+	}
+}
+
+void kpatch_rebuild_rela_section_data(struct section *sec)
+{
+	struct rela *rela;
+	int nr = 0, index = 0, size;
+	GElf_Rela *relas;
+
+	list_for_each_entry(rela, &sec->relas, list)
+		nr++;
+
+	size = nr * sizeof(*relas);
+	relas = malloc(size);
+	if (!relas)
+		ERROR("malloc");
+
+	sec->data->d_buf = relas;
+	sec->data->d_size = size;
+	/* d_type remains ELF_T_RELA */
+
+	sec->sh.sh_size = size;
+
+	list_for_each_entry(rela, &sec->relas, list) {
+		relas[index].r_offset = rela->offset;
+		relas[index].r_addend = rela->addend;
+		relas[index].r_info = GELF_R_INFO(rela->sym->index, rela->type);
+		index++;
+	}
+
+	/* sanity check, index should equal nr */
+	if (index != nr)
+		ERROR("size mismatch in rebuilt rela section");
+}
+
 void kpatch_write_output_elf(struct kpatch_elf *kelf, Elf *elf, char *outfile)
 {
 	int fd;

kpatch-build/kpatch-elf.h

@@ -150,6 +150,8 @@ void kpatch_create_strtab(struct kpatch_elf *kelf);
 void kpatch_create_symtab(struct kpatch_elf *kelf);
 struct section *create_section_pair(struct kpatch_elf *kelf, char *name,
                                     int entsize, int nr);
+void kpatch_reindex_elements(struct kpatch_elf *kelf);
+void kpatch_rebuild_rela_section_data(struct section *sec);
 void kpatch_write_output_elf(struct kpatch_elf *kelf, Elf *elf, char *outfile);
 void kpatch_elf_teardown(struct kpatch_elf *kelf);
 void kpatch_elf_free(struct kpatch_elf *kelf);