diff --git a/include/grub/i386/multiboot.h b/include/grub/i386/multiboot.h index 2dd7ec0..bd3c573 100644 --- a/include/grub/i386/multiboot.h +++ b/include/grub/i386/multiboot.h @@ -27,16 +27,11 @@ void grub_multiboot2_real_boot (grub_addr_t entry, struct grub_multiboot_info *mbi) __attribute__ ((noreturn)); -extern grub_addr_t grub_multiboot_payload_orig; +extern grub_uint32_t grub_multiboot_payload_eip; +extern char *grub_multiboot_payload_orig; extern grub_addr_t grub_multiboot_payload_dest; extern grub_size_t grub_multiboot_payload_size; -extern grub_uint32_t grub_multiboot_payload_entry_offset; -extern grub_uint8_t grub_multiboot_forward_relocator; -extern grub_uint8_t grub_multiboot_forward_relocator_end; -extern grub_uint8_t grub_multiboot_backward_relocator; -extern grub_uint8_t grub_multiboot_backward_relocator_end; - -#define RELOCATOR_SIZEOF(x) (&grub_multiboot_##x##_relocator_end - &grub_multiboot_##x##_relocator) +#define GRUB_MULTIBOOT_STACK_SIZE 4096 #endif /* ! GRUB_MULTIBOOT_CPU_HEADER */ diff --git a/loader/i386/multiboot.c b/loader/i386/multiboot.c index 87ffcae..974395f 100644 --- a/loader/i386/multiboot.c +++ b/loader/i386/multiboot.c @@ -48,18 +48,35 @@ #include #include #endif +#include extern grub_dl_t my_mod; static struct grub_multiboot_info *mbi, *mbi_dest; -static grub_addr_t entry; -static char *playground; static grub_size_t code_size; +char *grub_multiboot_payload_orig; +grub_addr_t grub_multiboot_payload_dest; +grub_size_t grub_multiboot_payload_size; +grub_uint32_t grub_multiboot_payload_eip; +grub_uint32_t grub_multiboot_payload_esp; + static grub_err_t grub_multiboot_boot (void) { - grub_multiboot_real_boot (entry, mbi_dest); + struct grub_relocator32_state state = + { + .eax = MULTIBOOT_MAGIC2, + .ebx = PTR_TO_UINT32 (mbi_dest), + .ecx = 0, + .edx = 0, + .eip = grub_multiboot_payload_eip, + .esp = grub_multiboot_payload_esp + }; + + grub_relocator32_boot (grub_multiboot_payload_orig, + grub_multiboot_payload_dest, + state); /* Not reached. */ return GRUB_ERR_NONE; @@ -248,11 +265,8 @@ grub_multiboot (int argc, char *argv[]) goto fail; } - if (playground) - { - grub_free (playground); - playground = NULL; - } + grub_relocator32_free (grub_multiboot_payload_orig); + grub_multiboot_payload_orig = NULL; mmap_length = grub_get_multiboot_mmap_len (); @@ -267,11 +281,13 @@ grub_multiboot (int argc, char *argv[]) ((void *) ((x) + code_size + cmdline_length)) #define mbi_addr(x) ((void *) ((x) + code_size + cmdline_length + boot_loader_name_length)) #define mmap_addr(x) ((void *) ((x) + code_size + cmdline_length + boot_loader_name_length + sizeof (struct grub_multiboot_info))) +#define stack_addr(x) ((void *) ((x) + code_size + cmdline_length + boot_loader_name_length + sizeof (struct grub_multiboot_info) + mmap_length + GRUB_MULTIBOOT_STACK_SIZE)) grub_multiboot_payload_size = cmdline_length /* boot_loader_name_length might need to grow for mbi,etc to be aligned (see below) */ + boot_loader_name_length + 3 - + sizeof (struct grub_multiboot_info) + mmap_length; + + sizeof (struct grub_multiboot_info) + mmap_length + + GRUB_MULTIBOOT_STACK_SIZE; if (header->flags & MULTIBOOT_AOUT_KLUDGE) { @@ -287,11 +303,12 @@ grub_multiboot (int argc, char *argv[]) grub_multiboot_payload_dest = header->load_addr; grub_multiboot_payload_size += code_size; - playground = grub_malloc (RELOCATOR_SIZEOF(forward) + grub_multiboot_payload_size + RELOCATOR_SIZEOF(backward)); - if (! playground) - goto fail; - grub_multiboot_payload_orig = (long) playground + RELOCATOR_SIZEOF(forward); + grub_multiboot_payload_orig + = grub_relocator32_alloc (grub_multiboot_payload_size); + + if (! grub_multiboot_payload_orig) + goto fail; if ((grub_file_seek (file, offset)) == (grub_off_t) - 1) goto fail; @@ -304,7 +321,7 @@ grub_multiboot (int argc, char *argv[]) grub_memset ((void *) (grub_multiboot_payload_orig + load_size), 0, header->bss_end_addr - header->load_addr - load_size); - grub_multiboot_payload_entry_offset = header->entry_addr - header->load_addr; + grub_multiboot_payload_eip = header->entry_addr; } else if (grub_multiboot_load_elf (file, buffer) != GRUB_ERR_NONE) @@ -325,23 +342,6 @@ grub_multiboot (int argc, char *argv[]) mbi->mmap_addr = (grub_uint32_t) mmap_addr (grub_multiboot_payload_dest); mbi->flags |= MULTIBOOT_INFO_MEM_MAP; - if (grub_multiboot_payload_dest >= grub_multiboot_payload_orig) - { - grub_memmove (playground, &grub_multiboot_forward_relocator, RELOCATOR_SIZEOF(forward)); - entry = (grub_addr_t) playground; - } - else - { - grub_memmove ((char *) (grub_multiboot_payload_orig + grub_multiboot_payload_size), - &grub_multiboot_backward_relocator, RELOCATOR_SIZEOF(backward)); - entry = (grub_addr_t) grub_multiboot_payload_orig + grub_multiboot_payload_size; - } - - grub_dprintf ("multiboot_loader", "dest=%p, size=0x%x, entry_offset=0x%x\n", - (void *) grub_multiboot_payload_dest, - grub_multiboot_payload_size, - grub_multiboot_payload_entry_offset); - /* Convert from bytes to kilobytes. */ mbi->mem_lower = grub_mmap_get_lower () / 1024; mbi->mem_upper = grub_mmap_get_upper () / 1024; @@ -371,6 +371,8 @@ grub_multiboot (int argc, char *argv[]) if (grub_multiboot_get_bootdev (&mbi->boot_device)) mbi->flags |= MULTIBOOT_INFO_BOOTDEV; + grub_multiboot_payload_esp = PTR_TO_UINT32 (stack_addr (grub_multiboot_payload_dest)); + grub_loader_set (grub_multiboot_boot, grub_multiboot_unload, 1); fail: diff --git a/loader/i386/multiboot_elfxx.c b/loader/i386/multiboot_elfxx.c index 77c4711..0b9820d 100644 --- a/loader/i386/multiboot_elfxx.c +++ b/loader/i386/multiboot_elfxx.c @@ -32,6 +32,8 @@ #error "I'm confused" #endif +#include + #define CONCAT(a,b) CONCAT_(a, b) #define CONCAT_(a,b) a ## b @@ -99,11 +101,12 @@ CONCAT(grub_multiboot_load_elf, XX) (grub_file_t file, void *buffer) grub_multiboot_payload_dest = phdr(lowest_segment)->p_paddr; grub_multiboot_payload_size += code_size; - playground = grub_malloc (RELOCATOR_SIZEOF(forward) + grub_multiboot_payload_size + RELOCATOR_SIZEOF(backward)); - if (! playground) - return grub_errno; - grub_multiboot_payload_orig = (long) playground + RELOCATOR_SIZEOF(forward); + grub_multiboot_payload_orig + = grub_relocator32_alloc (grub_multiboot_payload_size); + + if (!grub_multiboot_payload_orig) + return grub_errno; /* Load every loadable segment in memory. */ for (i = 0; i < ehdr->e_phnum; i++) @@ -135,8 +138,7 @@ CONCAT(grub_multiboot_load_elf, XX) (grub_file_t file, void *buffer) if (phdr(i)->p_vaddr <= ehdr->e_entry && phdr(i)->p_vaddr + phdr(i)->p_memsz > ehdr->e_entry) { - grub_multiboot_payload_entry_offset = (ehdr->e_entry - phdr(i)->p_vaddr) - + (phdr(i)->p_paddr - phdr(lowest_segment)->p_paddr); + grub_multiboot_payload_eip = ehdr->e_entry; break; } diff --git a/loader/i386/multiboot_helper.S b/loader/i386/multiboot_helper.S index d109458..2f9af77 100644 --- a/loader/i386/multiboot_helper.S +++ b/loader/i386/multiboot_helper.S @@ -23,81 +23,6 @@ .p2align 2 /* force 4-byte alignment */ /* - * This starts the multiboot kernel. - */ - -VARIABLE(grub_multiboot_payload_size) - .long 0 -VARIABLE(grub_multiboot_payload_orig) - .long 0 -VARIABLE(grub_multiboot_payload_dest) - .long 0 -VARIABLE(grub_multiboot_payload_entry_offset) - .long 0 - -/* - * The relocators below understand the following parameters: - * ecx: Size of the block to be copied. - * esi: Where to copy from (always lowest address, even if we're relocating - * backwards). - * edi: Where to copy to (likewise). - * edx: Offset of the entry point (relative to the beginning of the block). - */ - -VARIABLE(grub_multiboot_forward_relocator) - /* Add entry offset. */ - addl %edi, %edx - - /* Forward copy. */ - cld - rep - movsb - - jmp *%edx -VARIABLE(grub_multiboot_forward_relocator_end) - -VARIABLE(grub_multiboot_backward_relocator) - /* Add entry offset (before %edi is mangled). */ - addl %edi, %edx - - /* Backward movsb is implicitly off-by-one. compensate that. */ - decl %esi - decl %edi - - /* Backward copy. */ - std - addl %ecx, %esi - addl %ecx, %edi - rep - movsb - - cld - jmp *%edx -VARIABLE(grub_multiboot_backward_relocator_end) - -FUNCTION(grub_multiboot_real_boot) - /* Push the entry address on the stack. */ - pushl %eax - /* Move the address of the multiboot information structure to ebx. */ - movl %edx,%ebx - - /* Interrupts should be disabled. */ - cli - - /* Where do we copy what from. */ - movl EXT_C(grub_multiboot_payload_size), %ecx - movl EXT_C(grub_multiboot_payload_orig), %esi - movl EXT_C(grub_multiboot_payload_dest), %edi - movl EXT_C(grub_multiboot_payload_entry_offset), %edx - - /* Move the magic value into eax. */ - movl $MULTIBOOT_MAGIC2, %eax - - /* Jump to the relocator. */ - popl %ebp - jmp *%ebp - -/* * This starts the multiboot 2 kernel. */