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-rw-r--r--arch/x86/vdso/vdso2c.h163
1 files changed, 163 insertions, 0 deletions
diff --git a/arch/x86/vdso/vdso2c.h b/arch/x86/vdso/vdso2c.h
new file mode 100644
index 000000000000..d1e99e1892c4
--- /dev/null
+++ b/arch/x86/vdso/vdso2c.h
@@ -0,0 +1,163 @@
+/*
+ * This file is included twice from vdso2c.c. It generates code for 32-bit
+ * and 64-bit vDSOs. We need both for 64-bit builds, since 32-bit vDSOs
+ * are built for 32-bit userspace.
+ */
+
+static void GOFUNC(void *addr, size_t len, FILE *outfile, const char *name)
+{
+ int found_load = 0;
+ unsigned long load_size = -1; /* Work around bogus warning */
+ unsigned long data_size;
+ Elf_Ehdr *hdr = (Elf_Ehdr *)addr;
+ int i;
+ unsigned long j;
+ Elf_Shdr *symtab_hdr = NULL, *strtab_hdr, *secstrings_hdr,
+ *alt_sec = NULL;
+ Elf_Dyn *dyn = 0, *dyn_end = 0;
+ const char *secstrings;
+ uint64_t syms[NSYMS] = {};
+
+ Elf_Phdr *pt = (Elf_Phdr *)(addr + GET_LE(hdr->e_phoff));
+
+ /* Walk the segment table. */
+ for (i = 0; i < GET_LE(hdr->e_phnum); i++) {
+ if (GET_LE(pt[i].p_type) == PT_LOAD) {
+ if (found_load)
+ fail("multiple PT_LOAD segs\n");
+
+ if (GET_LE(pt[i].p_offset) != 0 ||
+ GET_LE(pt[i].p_vaddr) != 0)
+ fail("PT_LOAD in wrong place\n");
+
+ if (GET_LE(pt[i].p_memsz) != GET_LE(pt[i].p_filesz))
+ fail("cannot handle memsz != filesz\n");
+
+ load_size = GET_LE(pt[i].p_memsz);
+ found_load = 1;
+ } else if (GET_LE(pt[i].p_type) == PT_DYNAMIC) {
+ dyn = addr + GET_LE(pt[i].p_offset);
+ dyn_end = addr + GET_LE(pt[i].p_offset) +
+ GET_LE(pt[i].p_memsz);
+ }
+ }
+ if (!found_load)
+ fail("no PT_LOAD seg\n");
+ data_size = (load_size + 4095) / 4096 * 4096;
+
+ /* Walk the dynamic table */
+ for (i = 0; dyn + i < dyn_end &&
+ GET_LE(dyn[i].d_tag) != DT_NULL; i++) {
+ typeof(dyn[i].d_tag) tag = GET_LE(dyn[i].d_tag);
+ if (tag == DT_REL || tag == DT_RELSZ ||
+ tag == DT_RELENT || tag == DT_TEXTREL)
+ fail("vdso image contains dynamic relocations\n");
+ }
+
+ /* Walk the section table */
+ secstrings_hdr = addr + GET_LE(hdr->e_shoff) +
+ GET_LE(hdr->e_shentsize)*GET_LE(hdr->e_shstrndx);
+ secstrings = addr + GET_LE(secstrings_hdr->sh_offset);
+ for (i = 0; i < GET_LE(hdr->e_shnum); i++) {
+ Elf_Shdr *sh = addr + GET_LE(hdr->e_shoff) +
+ GET_LE(hdr->e_shentsize) * i;
+ if (GET_LE(sh->sh_type) == SHT_SYMTAB)
+ symtab_hdr = sh;
+
+ if (!strcmp(secstrings + GET_LE(sh->sh_name),
+ ".altinstructions"))
+ alt_sec = sh;
+ }
+
+ if (!symtab_hdr)
+ fail("no symbol table\n");
+
+ strtab_hdr = addr + GET_LE(hdr->e_shoff) +
+ GET_LE(hdr->e_shentsize) * GET_LE(symtab_hdr->sh_link);
+
+ /* Walk the symbol table */
+ for (i = 0;
+ i < GET_LE(symtab_hdr->sh_size) / GET_LE(symtab_hdr->sh_entsize);
+ i++) {
+ int k;
+ Elf_Sym *sym = addr + GET_LE(symtab_hdr->sh_offset) +
+ GET_LE(symtab_hdr->sh_entsize) * i;
+ const char *name = addr + GET_LE(strtab_hdr->sh_offset) +
+ GET_LE(sym->st_name);
+ for (k = 0; k < NSYMS; k++) {
+ if (!strcmp(name, required_syms[k])) {
+ if (syms[k]) {
+ fail("duplicate symbol %s\n",
+ required_syms[k]);
+ }
+ syms[k] = GET_LE(sym->st_value);
+ }
+ }
+ }
+
+ /* Validate mapping addresses. */
+ for (i = 0; i < sizeof(special_pages) / sizeof(special_pages[0]); i++) {
+ if (!syms[i])
+ continue; /* The mapping isn't used; ignore it. */
+
+ if (syms[i] % 4096)
+ fail("%s must be a multiple of 4096\n",
+ required_syms[i]);
+ if (syms[i] < data_size)
+ fail("%s must be after the text mapping\n",
+ required_syms[i]);
+ if (syms[sym_end_mapping] < syms[i] + 4096)
+ fail("%s overruns end_mapping\n", required_syms[i]);
+ }
+ if (syms[sym_end_mapping] % 4096)
+ fail("end_mapping must be a multiple of 4096\n");
+
+ /* Remove sections. */
+ hdr->e_shoff = 0;
+ hdr->e_shentsize = 0;
+ hdr->e_shnum = 0;
+ hdr->e_shstrndx = htole16(SHN_UNDEF);
+
+ if (!name) {
+ fwrite(addr, load_size, 1, outfile);
+ return;
+ }
+
+ fprintf(outfile, "/* AUTOMATICALLY GENERATED -- DO NOT EDIT */\n\n");
+ fprintf(outfile, "#include <linux/linkage.h>\n");
+ fprintf(outfile, "#include <asm/page_types.h>\n");
+ fprintf(outfile, "#include <asm/vdso.h>\n");
+ fprintf(outfile, "\n");
+ fprintf(outfile,
+ "static unsigned char raw_data[%lu] __page_aligned_data = {",
+ data_size);
+ for (j = 0; j < load_size; j++) {
+ if (j % 10 == 0)
+ fprintf(outfile, "\n\t");
+ fprintf(outfile, "0x%02X, ", (int)((unsigned char *)addr)[j]);
+ }
+ fprintf(outfile, "\n};\n\n");
+
+ fprintf(outfile, "static struct page *pages[%lu];\n\n",
+ data_size / 4096);
+
+ fprintf(outfile, "const struct vdso_image %s = {\n", name);
+ fprintf(outfile, "\t.data = raw_data,\n");
+ fprintf(outfile, "\t.size = %lu,\n", data_size);
+ fprintf(outfile, "\t.text_mapping = {\n");
+ fprintf(outfile, "\t\t.name = \"[vdso]\",\n");
+ fprintf(outfile, "\t\t.pages = pages,\n");
+ fprintf(outfile, "\t},\n");
+ if (alt_sec) {
+ fprintf(outfile, "\t.alt = %lu,\n",
+ (unsigned long)GET_LE(alt_sec->sh_offset));
+ fprintf(outfile, "\t.alt_len = %lu,\n",
+ (unsigned long)GET_LE(alt_sec->sh_size));
+ }
+ for (i = 0; i < NSYMS; i++) {
+ if (syms[i])
+ fprintf(outfile, "\t.sym_%s = 0x%" PRIx64 ",\n",
+ required_syms[i], syms[i]);
+ }
+ fprintf(outfile, "};\n");
+}