diff options
Diffstat (limited to 'arch/s390/tools')
| -rw-r--r-- | arch/s390/tools/.gitignore | 1 | ||||
| -rw-r--r-- | arch/s390/tools/Makefile | 5 | ||||
| -rw-r--r-- | arch/s390/tools/relocs.c | 387 |
3 files changed, 393 insertions, 0 deletions
diff --git a/arch/s390/tools/.gitignore b/arch/s390/tools/.gitignore index ea62f37b79..e6af51d9d1 100644 --- a/arch/s390/tools/.gitignore +++ b/arch/s390/tools/.gitignore @@ -1,3 +1,4 @@ # SPDX-License-Identifier: GPL-2.0-only gen_facilities gen_opcode_table +relocs diff --git a/arch/s390/tools/Makefile b/arch/s390/tools/Makefile index f9dd47ff9a..f2862364fb 100644 --- a/arch/s390/tools/Makefile +++ b/arch/s390/tools/Makefile @@ -25,3 +25,8 @@ $(kapi)/facility-defs.h: $(obj)/gen_facilities FORCE $(kapi)/dis-defs.h: $(obj)/gen_opcode_table FORCE $(call filechk,dis-defs.h) + +hostprogs += relocs +PHONY += relocs +relocs: $(obj)/relocs + @: diff --git a/arch/s390/tools/relocs.c b/arch/s390/tools/relocs.c new file mode 100644 index 0000000000..30a732c808 --- /dev/null +++ b/arch/s390/tools/relocs.c @@ -0,0 +1,387 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <stdio.h> +#include <stdarg.h> +#include <stdlib.h> +#include <stdint.h> +#include <inttypes.h> +#include <string.h> +#include <errno.h> +#include <unistd.h> +#include <elf.h> +#include <byteswap.h> +#define USE_BSD +#include <endian.h> + +#define ELF_BITS 64 + +#define ELF_MACHINE EM_S390 +#define ELF_MACHINE_NAME "IBM S/390" +#define SHT_REL_TYPE SHT_RELA +#define Elf_Rel Elf64_Rela + +#define ELF_CLASS ELFCLASS64 +#define ELF_ENDIAN ELFDATA2MSB +#define ELF_R_SYM(val) ELF64_R_SYM(val) +#define ELF_R_TYPE(val) ELF64_R_TYPE(val) +#define ELF_ST_TYPE(o) ELF64_ST_TYPE(o) +#define ELF_ST_BIND(o) ELF64_ST_BIND(o) +#define ELF_ST_VISIBILITY(o) ELF64_ST_VISIBILITY(o) + +#define ElfW(type) _ElfW(ELF_BITS, type) +#define _ElfW(bits, type) __ElfW(bits, type) +#define __ElfW(bits, type) Elf##bits##_##type + +#define Elf_Addr ElfW(Addr) +#define Elf_Ehdr ElfW(Ehdr) +#define Elf_Phdr ElfW(Phdr) +#define Elf_Shdr ElfW(Shdr) +#define Elf_Sym ElfW(Sym) + +static Elf_Ehdr ehdr; +static unsigned long shnum; +static unsigned int shstrndx; + +struct relocs { + uint32_t *offset; + unsigned long count; + unsigned long size; +}; + +static struct relocs relocs64; +#define FMT PRIu64 + +struct section { + Elf_Shdr shdr; + struct section *link; + Elf_Rel *reltab; +}; + +static struct section *secs; + +#if BYTE_ORDER == LITTLE_ENDIAN +#define le16_to_cpu(val) (val) +#define le32_to_cpu(val) (val) +#define le64_to_cpu(val) (val) +#define be16_to_cpu(val) bswap_16(val) +#define be32_to_cpu(val) bswap_32(val) +#define be64_to_cpu(val) bswap_64(val) +#endif + +#if BYTE_ORDER == BIG_ENDIAN +#define le16_to_cpu(val) bswap_16(val) +#define le32_to_cpu(val) bswap_32(val) +#define le64_to_cpu(val) bswap_64(val) +#define be16_to_cpu(val) (val) +#define be32_to_cpu(val) (val) +#define be64_to_cpu(val) (val) +#endif + +static uint16_t elf16_to_cpu(uint16_t val) +{ + if (ehdr.e_ident[EI_DATA] == ELFDATA2LSB) + return le16_to_cpu(val); + else + return be16_to_cpu(val); +} + +static uint32_t elf32_to_cpu(uint32_t val) +{ + if (ehdr.e_ident[EI_DATA] == ELFDATA2LSB) + return le32_to_cpu(val); + else + return be32_to_cpu(val); +} + +#define elf_half_to_cpu(x) elf16_to_cpu(x) +#define elf_word_to_cpu(x) elf32_to_cpu(x) + +static uint64_t elf64_to_cpu(uint64_t val) +{ + return be64_to_cpu(val); +} + +#define elf_addr_to_cpu(x) elf64_to_cpu(x) +#define elf_off_to_cpu(x) elf64_to_cpu(x) +#define elf_xword_to_cpu(x) elf64_to_cpu(x) + +static void die(char *fmt, ...) +{ + va_list ap; + + va_start(ap, fmt); + vfprintf(stderr, fmt, ap); + va_end(ap); + exit(1); +} + +static void read_ehdr(FILE *fp) +{ + if (fread(&ehdr, sizeof(ehdr), 1, fp) != 1) + die("Cannot read ELF header: %s\n", strerror(errno)); + if (memcmp(ehdr.e_ident, ELFMAG, SELFMAG) != 0) + die("No ELF magic\n"); + if (ehdr.e_ident[EI_CLASS] != ELF_CLASS) + die("Not a %d bit executable\n", ELF_BITS); + if (ehdr.e_ident[EI_DATA] != ELF_ENDIAN) + die("ELF endian mismatch\n"); + if (ehdr.e_ident[EI_VERSION] != EV_CURRENT) + die("Unknown ELF version\n"); + + /* Convert the fields to native endian */ + ehdr.e_type = elf_half_to_cpu(ehdr.e_type); + ehdr.e_machine = elf_half_to_cpu(ehdr.e_machine); + ehdr.e_version = elf_word_to_cpu(ehdr.e_version); + ehdr.e_entry = elf_addr_to_cpu(ehdr.e_entry); + ehdr.e_phoff = elf_off_to_cpu(ehdr.e_phoff); + ehdr.e_shoff = elf_off_to_cpu(ehdr.e_shoff); + ehdr.e_flags = elf_word_to_cpu(ehdr.e_flags); + ehdr.e_ehsize = elf_half_to_cpu(ehdr.e_ehsize); + ehdr.e_phentsize = elf_half_to_cpu(ehdr.e_phentsize); + ehdr.e_phnum = elf_half_to_cpu(ehdr.e_phnum); + ehdr.e_shentsize = elf_half_to_cpu(ehdr.e_shentsize); + ehdr.e_shnum = elf_half_to_cpu(ehdr.e_shnum); + ehdr.e_shstrndx = elf_half_to_cpu(ehdr.e_shstrndx); + + shnum = ehdr.e_shnum; + shstrndx = ehdr.e_shstrndx; + + if ((ehdr.e_type != ET_EXEC) && (ehdr.e_type != ET_DYN)) + die("Unsupported ELF header type\n"); + if (ehdr.e_machine != ELF_MACHINE) + die("Not for %s\n", ELF_MACHINE_NAME); + if (ehdr.e_version != EV_CURRENT) + die("Unknown ELF version\n"); + if (ehdr.e_ehsize != sizeof(Elf_Ehdr)) + die("Bad Elf header size\n"); + if (ehdr.e_phentsize != sizeof(Elf_Phdr)) + die("Bad program header entry\n"); + if (ehdr.e_shentsize != sizeof(Elf_Shdr)) + die("Bad section header entry\n"); + + if (shnum == SHN_UNDEF || shstrndx == SHN_XINDEX) { + Elf_Shdr shdr; + + if (fseek(fp, ehdr.e_shoff, SEEK_SET) < 0) + die("Seek to %" FMT " failed: %s\n", ehdr.e_shoff, strerror(errno)); + + if (fread(&shdr, sizeof(shdr), 1, fp) != 1) + die("Cannot read initial ELF section header: %s\n", strerror(errno)); + + if (shnum == SHN_UNDEF) + shnum = elf_xword_to_cpu(shdr.sh_size); + + if (shstrndx == SHN_XINDEX) + shstrndx = elf_word_to_cpu(shdr.sh_link); + } + + if (shstrndx >= shnum) + die("String table index out of bounds\n"); +} + +static void read_shdrs(FILE *fp) +{ + Elf_Shdr shdr; + int i; + + secs = calloc(shnum, sizeof(struct section)); + if (!secs) + die("Unable to allocate %ld section headers\n", shnum); + + if (fseek(fp, ehdr.e_shoff, SEEK_SET) < 0) + die("Seek to %" FMT " failed: %s\n", ehdr.e_shoff, strerror(errno)); + + for (i = 0; i < shnum; i++) { + struct section *sec = &secs[i]; + + if (fread(&shdr, sizeof(shdr), 1, fp) != 1) { + die("Cannot read ELF section headers %d/%ld: %s\n", + i, shnum, strerror(errno)); + } + + sec->shdr.sh_name = elf_word_to_cpu(shdr.sh_name); + sec->shdr.sh_type = elf_word_to_cpu(shdr.sh_type); + sec->shdr.sh_flags = elf_xword_to_cpu(shdr.sh_flags); + sec->shdr.sh_addr = elf_addr_to_cpu(shdr.sh_addr); + sec->shdr.sh_offset = elf_off_to_cpu(shdr.sh_offset); + sec->shdr.sh_size = elf_xword_to_cpu(shdr.sh_size); + sec->shdr.sh_link = elf_word_to_cpu(shdr.sh_link); + sec->shdr.sh_info = elf_word_to_cpu(shdr.sh_info); + sec->shdr.sh_addralign = elf_xword_to_cpu(shdr.sh_addralign); + sec->shdr.sh_entsize = elf_xword_to_cpu(shdr.sh_entsize); + + if (sec->shdr.sh_link < shnum) + sec->link = &secs[sec->shdr.sh_link]; + } + +} + +static void read_relocs(FILE *fp) +{ + int i, j; + + for (i = 0; i < shnum; i++) { + struct section *sec = &secs[i]; + + if (sec->shdr.sh_type != SHT_REL_TYPE) + continue; + + sec->reltab = malloc(sec->shdr.sh_size); + if (!sec->reltab) + die("malloc of %" FMT " bytes for relocs failed\n", sec->shdr.sh_size); + + if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0) + die("Seek to %" FMT " failed: %s\n", sec->shdr.sh_offset, strerror(errno)); + + if (fread(sec->reltab, 1, sec->shdr.sh_size, fp) != sec->shdr.sh_size) + die("Cannot read symbol table: %s\n", strerror(errno)); + + for (j = 0; j < sec->shdr.sh_size / sizeof(Elf_Rel); j++) { + Elf_Rel *rel = &sec->reltab[j]; + + rel->r_offset = elf_addr_to_cpu(rel->r_offset); + rel->r_info = elf_xword_to_cpu(rel->r_info); +#if (SHT_REL_TYPE == SHT_RELA) + rel->r_addend = elf_xword_to_cpu(rel->r_addend); +#endif + } + } +} + +static void add_reloc(struct relocs *r, uint32_t offset) +{ + if (r->count == r->size) { + unsigned long newsize = r->size + 50000; + void *mem = realloc(r->offset, newsize * sizeof(r->offset[0])); + + if (!mem) + die("realloc of %ld entries for relocs failed\n", newsize); + + r->offset = mem; + r->size = newsize; + } + r->offset[r->count++] = offset; +} + +static int do_reloc(struct section *sec, Elf_Rel *rel) +{ + unsigned int r_type = ELF64_R_TYPE(rel->r_info); + ElfW(Addr) offset = rel->r_offset; + + switch (r_type) { + case R_390_NONE: + case R_390_PC32: + case R_390_PC64: + case R_390_PC16DBL: + case R_390_PC32DBL: + case R_390_PLT32DBL: + case R_390_GOTENT: + case R_390_GOTPCDBL: + case R_390_GOTOFF64: + break; + case R_390_64: + add_reloc(&relocs64, offset); + break; + default: + die("Unsupported relocation type: %d\n", r_type); + break; + } + + return 0; +} + +static void walk_relocs(void) +{ + int i; + + /* Walk through the relocations */ + for (i = 0; i < shnum; i++) { + struct section *sec_applies; + int j; + struct section *sec = &secs[i]; + + if (sec->shdr.sh_type != SHT_REL_TYPE) + continue; + + sec_applies = &secs[sec->shdr.sh_info]; + if (!(sec_applies->shdr.sh_flags & SHF_ALLOC)) + continue; + + for (j = 0; j < sec->shdr.sh_size / sizeof(Elf_Rel); j++) { + Elf_Rel *rel = &sec->reltab[j]; + + do_reloc(sec, rel); + } + } +} + +static int cmp_relocs(const void *va, const void *vb) +{ + const uint32_t *a, *b; + + a = va; b = vb; + return (*a == *b) ? 0 : (*a > *b) ? 1 : -1; +} + +static void sort_relocs(struct relocs *r) +{ + qsort(r->offset, r->count, sizeof(r->offset[0]), cmp_relocs); +} + +static int print_reloc(uint32_t v) +{ + return fprintf(stdout, "\t.long 0x%08"PRIx32"\n", v) > 0 ? 0 : -1; +} + +static void emit_relocs(void) +{ + int i; + + walk_relocs(); + sort_relocs(&relocs64); + + printf(".section \".vmlinux.relocs_64\",\"a\"\n"); + for (i = 0; i < relocs64.count; i++) + print_reloc(relocs64.offset[i]); +} + +static void process(FILE *fp) +{ + read_ehdr(fp); + read_shdrs(fp); + read_relocs(fp); + emit_relocs(); +} + +static void usage(void) +{ + die("relocs vmlinux\n"); +} + +int main(int argc, char **argv) +{ + unsigned char e_ident[EI_NIDENT]; + const char *fname; + FILE *fp; + + fname = NULL; + + if (argc != 2) + usage(); + + fname = argv[1]; + + fp = fopen(fname, "r"); + if (!fp) + die("Cannot open %s: %s\n", fname, strerror(errno)); + + if (fread(&e_ident, 1, EI_NIDENT, fp) != EI_NIDENT) + die("Cannot read %s: %s", fname, strerror(errno)); + + rewind(fp); + + process(fp); + + fclose(fp); + return 0; +} |