hw/loader: Pass ELFDATA endian order argument to load_elf_ram_sym()

Rather than passing a boolean 'is_big_endian' argument,
directly pass the ELFDATA, which can be unspecified using
the ELFDATANONE value.

Update the call sites:
  0 -> ELFDATA2LSB

Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20250127113824.50177-5-philmd@linaro.org>

hw/core/loader.c

@@ -428,7 +428,8 @@ ssize_t load_elf_as(const char *filename,
 {
     return load_elf_ram_sym(filename, elf_note_fn,
                             translate_fn, translate_opaque,
-                            pentry, lowaddr, highaddr, pflags, big_endian,
+                            pentry, lowaddr, highaddr, pflags,
+                            big_endian ? ELFDATA2MSB : ELFDATA2LSB,
                             elf_machine, clear_lsb, data_swab, as,
                             true, NULL);
 }
@@ -439,12 +440,12 @@ ssize_t load_elf_ram_sym(const char *filename,
                          uint64_t (*translate_fn)(void *, uint64_t),
                          void *translate_opaque, uint64_t *pentry,
                          uint64_t *lowaddr, uint64_t *highaddr,
-                         uint32_t *pflags, int big_endian, int elf_machine,
+                         uint32_t *pflags, int elf_data_order, int elf_machine,
                          int clear_lsb, int data_swab,
                          AddressSpace *as, bool load_rom, symbol_fn_t sym_cb)
 {
     const int host_data_order = HOST_BIG_ENDIAN ? ELFDATA2MSB : ELFDATA2LSB;
-    int fd, target_data_order, must_swab;
+    int fd, must_swab;
     ssize_t ret = ELF_LOAD_FAILED;
     uint8_t e_ident[EI_NIDENT];
 
@@ -462,18 +463,14 @@ ssize_t load_elf_ram_sym(const char *filename,
         ret = ELF_LOAD_NOT_ELF;
         goto fail;
     }
-    must_swab = host_data_order != e_ident[EI_DATA];
-    if (big_endian) {
-        target_data_order = ELFDATA2MSB;
-    } else {
-        target_data_order = ELFDATA2LSB;
-    }
 
-    if (target_data_order != e_ident[EI_DATA]) {
+    if (elf_data_order != ELFDATANONE && elf_data_order != e_ident[EI_DATA]) {
         ret = ELF_LOAD_WRONG_ENDIAN;
         goto fail;
     }
 
+    must_swab = host_data_order != e_ident[EI_DATA];
+
     lseek(fd, 0, SEEK_SET);
     if (e_ident[EI_CLASS] == ELFCLASS64) {
         ret = load_elf64(filename, fd, elf_note_fn,

hw/riscv/boot.c

@@ -246,7 +246,8 @@ void riscv_load_kernel(MachineState *machine,
      */
     kernel_size = load_elf_ram_sym(kernel_filename, NULL, NULL, NULL, NULL,
                                    &info->image_low_addr, &info->image_high_addr,
-                                   NULL, 0, EM_RISCV, 1, 0, NULL, true, sym_cb);
+                                   NULL, ELFDATA2LSB, EM_RISCV,
+                                   1, 0, NULL, true, sym_cb);
     if (kernel_size > 0) {
         info->kernel_size = kernel_size;
         goto out;

include/hw/loader.h

@@ -120,7 +120,7 @@ const char *load_elf_strerror(ssize_t error);
  * @lowaddr: Populated with lowest loaded address. Ignored if NULL.
  * @highaddr: Populated with highest loaded address. Ignored if NULL.
  * @pflags: Populated with ELF processor-specific flags. Ignore if NULL.
- * @bigendian: Expected ELF endianness. 0 for LE otherwise BE
+ * @elf_data_order: Expected ELF endianness (ELFDATA2LSB or ELFDATA2MSB).
  * @elf_machine: Expected ELF machine type
  * @clear_lsb: Set to mask off LSB of addresses (Some architectures use
  *             this for non-address data)
@@ -151,7 +151,7 @@ ssize_t load_elf_ram_sym(const char *filename,
                          uint64_t (*translate_fn)(void *, uint64_t),
                          void *translate_opaque, uint64_t *pentry,
                          uint64_t *lowaddr, uint64_t *highaddr,
-                         uint32_t *pflags, int big_endian, int elf_machine,
+                         uint32_t *pflags, int elf_data_order, int elf_machine,
                          int clear_lsb, int data_swab,
                          AddressSpace *as, bool load_rom, symbol_fn_t sym_cb);