modpost: clean up MIPS64 little endian relocation code

MIPS64 little endian target has an odd encoding of r_info.

This commit makes the special handling less ugly. It is still ugly,
but #if conditionals will go away, at least.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
index 570a6cb..ca04b87 100644 (file)
--- a/scripts/mod/modpost.c
+++ b/scripts/mod/modpost.c
@@ -1426,6 +1426,41 @@ static Elf_Addr addend_mips_rel(uint32_t *location, unsigned int r_type)
 #define R_LARCH_SUB32          55
 #endif
 
+static void get_rel_type_and_sym(struct elf_info *elf, uint64_t r_info,
+                                unsigned int *r_type, unsigned int *r_sym)
+{
+       typedef struct {
+               Elf64_Word    r_sym;    /* Symbol index */
+               unsigned char r_ssym;   /* Special symbol for 2nd relocation */
+               unsigned char r_type3;  /* 3rd relocation type */
+               unsigned char r_type2;  /* 2nd relocation type */
+               unsigned char r_type;   /* 1st relocation type */
+       } Elf64_Mips_R_Info;
+
+       bool is_64bit = (elf->hdr->e_ident[EI_CLASS] == ELFCLASS64);
+
+       if (elf->hdr->e_machine == EM_MIPS && is_64bit) {
+               Elf64_Mips_R_Info *mips64_r_info = (void *)&r_info;
+
+               *r_type = mips64_r_info->r_type;
+               *r_sym = TO_NATIVE(mips64_r_info->r_sym);
+               return;
+       }
+
+       if (is_64bit) {
+               Elf64_Xword r_info64 = r_info;
+
+               r_info = TO_NATIVE(r_info64);
+       } else {
+               Elf32_Word r_info32 = r_info;
+
+               r_info = TO_NATIVE(r_info32);
+       }
+
+       *r_type = ELF_R_TYPE(r_info);
+       *r_sym = ELF_R_SYM(r_info);
+}
+
 static void section_rela(struct module *mod, struct elf_info *elf,
                         Elf_Shdr *sechdr)
 {
@@ -1442,32 +1477,21 @@ static void section_rela(struct module *mod, struct elf_info *elf,
                return;
 
        for (rela = start; rela < stop; rela++) {
+               unsigned int r_type;
+
                r.r_offset = TO_NATIVE(rela->r_offset);
-#if KERNEL_ELFCLASS == ELFCLASS64
-               if (elf->hdr->e_machine == EM_MIPS) {
-                       unsigned int r_typ;
-                       r_sym = ELF64_MIPS_R_SYM(rela->r_info);
-                       r_sym = TO_NATIVE(r_sym);
-                       r_typ = ELF64_MIPS_R_TYPE(rela->r_info);
-                       r.r_info = ELF64_R_INFO(r_sym, r_typ);
-               } else {
-                       r.r_info = TO_NATIVE(rela->r_info);
-                       r_sym = ELF_R_SYM(r.r_info);
-               }
-#else
-               r.r_info = TO_NATIVE(rela->r_info);
-               r_sym = ELF_R_SYM(r.r_info);
-#endif
+               get_rel_type_and_sym(elf, rela->r_info, &r_type, &r_sym);
+
                r.r_addend = TO_NATIVE(rela->r_addend);
                switch (elf->hdr->e_machine) {
                case EM_RISCV:
                        if (!strcmp("__ex_table", fromsec) &&
-                           ELF_R_TYPE(r.r_info) == R_RISCV_SUB32)
+                           r_type == R_RISCV_SUB32)
                                continue;
                        break;
                case EM_LOONGARCH:
                        if (!strcmp("__ex_table", fromsec) &&
-                           ELF_R_TYPE(r.r_info) == R_LARCH_SUB32)
+                           r_type == R_LARCH_SUB32)
                                continue;
                        break;
                }
@@ -1499,25 +1523,11 @@ static void section_rel(struct module *mod, struct elf_info *elf,
                unsigned int r_type;
 
                r.r_offset = TO_NATIVE(rel->r_offset);
-#if KERNEL_ELFCLASS == ELFCLASS64
-               if (elf->hdr->e_machine == EM_MIPS) {
-                       unsigned int r_typ;
-                       r_sym = ELF64_MIPS_R_SYM(rel->r_info);
-                       r_sym = TO_NATIVE(r_sym);
-                       r_typ = ELF64_MIPS_R_TYPE(rel->r_info);
-                       r.r_info = ELF64_R_INFO(r_sym, r_typ);
-               } else {
-                       r.r_info = TO_NATIVE(rel->r_info);
-                       r_sym = ELF_R_SYM(r.r_info);
-               }
-#else
-               r.r_info = TO_NATIVE(rel->r_info);
-               r_sym = ELF_R_SYM(r.r_info);
-#endif
+
+               get_rel_type_and_sym(elf, rel->r_info, &r_type, &r_sym);
 
                loc = sym_get_data_by_offset(elf, fsecndx, r.r_offset);
                tsym = elf->symtab_start + r_sym;
-               r_type = ELF_R_TYPE(r.r_info);
 
                switch (elf->hdr->e_machine) {
                case EM_386:

diff --git a/scripts/mod/modpost.h b/scripts/mod/modpost.h
index dfdb948..5f94c2c 100644 (file)
--- a/scripts/mod/modpost.h
+++ b/scripts/mod/modpost.h
@@ -50,28 +50,6 @@
 #define ELF_R_TYPE  ELF64_R_TYPE
 #endif
 
-/* The 64-bit MIPS ELF ABI uses an unusual reloc format. */
-typedef struct
-{
-       Elf32_Word    r_sym;    /* Symbol index */
-       unsigned char r_ssym;   /* Special symbol for 2nd relocation */
-       unsigned char r_type3;  /* 3rd relocation type */
-       unsigned char r_type2;  /* 2nd relocation type */
-       unsigned char r_type1;  /* 1st relocation type */
-} _Elf64_Mips_R_Info;
-
-typedef union
-{
-       Elf64_Xword             r_info_number;
-       _Elf64_Mips_R_Info      r_info_fields;
-} _Elf64_Mips_R_Info_union;
-
-#define ELF64_MIPS_R_SYM(i) \
-  ((__extension__ (_Elf64_Mips_R_Info_union)(i)).r_info_fields.r_sym)
-
-#define ELF64_MIPS_R_TYPE(i) \
-  ((__extension__ (_Elf64_Mips_R_Info_union)(i)).r_info_fields.r_type1)
-
 #if KERNEL_ELFDATA != HOST_ELFDATA
 
 static inline void __endian(const void *src, void *dest, unsigned int size)