diff options
Diffstat (limited to 'arch/sparc/vdso/vdso2c.h')
| -rw-r--r-- | arch/sparc/vdso/vdso2c.h | 143 |
1 files changed, 143 insertions, 0 deletions
diff --git a/arch/sparc/vdso/vdso2c.h b/arch/sparc/vdso/vdso2c.h new file mode 100644 index 000000000000..808decb0f7be --- /dev/null +++ b/arch/sparc/vdso/vdso2c.h @@ -0,0 +1,143 @@ +/* + * Copyright (c) 2017 Oracle and/or its affiliates. All rights reserved. + */ + +/* + * This file is included up to twice from vdso2c.c. It generates code for + * 32-bit and 64-bit vDSOs. We will eventually need both for 64-bit builds, + * since 32-bit vDSOs will then be built for 32-bit userspace. + */ + +static void BITSFUNC(go)(void *raw_addr, size_t raw_len, + void *stripped_addr, size_t stripped_len, + FILE *outfile, const char *name) +{ + int found_load = 0; + unsigned long load_size = -1; /* Work around bogus warning */ + unsigned long mapping_size; + int i; + unsigned long j; + + ELF(Shdr) *symtab_hdr = NULL, *strtab_hdr; + ELF(Ehdr) *hdr = (ELF(Ehdr) *)raw_addr; + ELF(Dyn) *dyn = 0, *dyn_end = 0; + INT_BITS syms[NSYMS] = {}; + + ELF(Phdr) *pt = (ELF(Phdr) *)(raw_addr + GET_BE(&hdr->e_phoff)); + + /* Walk the segment table. */ + for (i = 0; i < GET_BE(&hdr->e_phnum); i++) { + if (GET_BE(&pt[i].p_type) == PT_LOAD) { + if (found_load) + fail("multiple PT_LOAD segs\n"); + + if (GET_BE(&pt[i].p_offset) != 0 || + GET_BE(&pt[i].p_vaddr) != 0) + fail("PT_LOAD in wrong place\n"); + + if (GET_BE(&pt[i].p_memsz) != GET_BE(&pt[i].p_filesz)) + fail("cannot handle memsz != filesz\n"); + + load_size = GET_BE(&pt[i].p_memsz); + found_load = 1; + } else if (GET_BE(&pt[i].p_type) == PT_DYNAMIC) { + dyn = raw_addr + GET_BE(&pt[i].p_offset); + dyn_end = raw_addr + GET_BE(&pt[i].p_offset) + + GET_BE(&pt[i].p_memsz); + } + } + if (!found_load) + fail("no PT_LOAD seg\n"); + + if (stripped_len < load_size) + fail("stripped input is too short\n"); + + /* Walk the dynamic table */ + for (i = 0; dyn + i < dyn_end && + GET_BE(&dyn[i].d_tag) != DT_NULL; i++) { + typeof(dyn[i].d_tag) tag = GET_BE(&dyn[i].d_tag); + typeof(dyn[i].d_un.d_val) val = GET_BE(&dyn[i].d_un.d_val); + + if ((tag == DT_RELSZ || tag == DT_RELASZ) && (val != 0)) + fail("vdso image contains dynamic relocations\n"); + } + + /* Walk the section table */ + for (i = 0; i < GET_BE(&hdr->e_shnum); i++) { + ELF(Shdr) *sh = raw_addr + GET_BE(&hdr->e_shoff) + + GET_BE(&hdr->e_shentsize) * i; + if (GET_BE(&sh->sh_type) == SHT_SYMTAB) + symtab_hdr = sh; + } + + if (!symtab_hdr) + fail("no symbol table\n"); + + strtab_hdr = raw_addr + GET_BE(&hdr->e_shoff) + + GET_BE(&hdr->e_shentsize) * GET_BE(&symtab_hdr->sh_link); + + /* Walk the symbol table */ + for (i = 0; + i < GET_BE(&symtab_hdr->sh_size) / GET_BE(&symtab_hdr->sh_entsize); + i++) { + int k; + + ELF(Sym) *sym = raw_addr + GET_BE(&symtab_hdr->sh_offset) + + GET_BE(&symtab_hdr->sh_entsize) * i; + const char *name = raw_addr + GET_BE(&strtab_hdr->sh_offset) + + GET_BE(&sym->st_name); + + for (k = 0; k < NSYMS; k++) { + if (!strcmp(name, required_syms[k].name)) { + if (syms[k]) { + fail("duplicate symbol %s\n", + required_syms[k].name); + } + + /* + * Careful: we use negative addresses, but + * st_value is unsigned, so we rely + * on syms[k] being a signed type of the + * correct width. + */ + syms[k] = GET_BE(&sym->st_value); + } + } + } + + /* Validate mapping addresses. */ + if (syms[sym_vvar_start] % 8192) + fail("vvar_begin must be a multiple of 8192\n"); + + if (!name) { + fwrite(stripped_addr, stripped_len, 1, outfile); + return; + } + + mapping_size = (stripped_len + 8191) / 8192 * 8192; + + fprintf(outfile, "/* AUTOMATICALLY GENERATED -- DO NOT EDIT */\n\n"); + fprintf(outfile, "#include <linux/cache.h>\n"); + fprintf(outfile, "#include <asm/vdso.h>\n"); + fprintf(outfile, "\n"); + fprintf(outfile, + "static unsigned char raw_data[%lu] __ro_after_init __aligned(8192)= {", + mapping_size); + for (j = 0; j < stripped_len; j++) { + if (j % 10 == 0) + fprintf(outfile, "\n\t"); + fprintf(outfile, "0x%02X, ", + (int)((unsigned char *)stripped_addr)[j]); + } + fprintf(outfile, "\n};\n\n"); + + fprintf(outfile, "const struct vdso_image %s_builtin = {\n", name); + fprintf(outfile, "\t.data = raw_data,\n"); + fprintf(outfile, "\t.size = %lu,\n", mapping_size); + for (i = 0; i < NSYMS; i++) { + if (required_syms[i].export && syms[i]) + fprintf(outfile, "\t.sym_%s = %" PRIi64 ",\n", + required_syms[i].name, (int64_t)syms[i]); + } + fprintf(outfile, "};\n"); +} |