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Diffstat (limited to 'arch/x86/vdso/vdso2c.h')
-rw-r--r--arch/x86/vdso/vdso2c.h137
1 files changed, 137 insertions, 0 deletions
diff --git a/arch/x86/vdso/vdso2c.h b/arch/x86/vdso/vdso2c.h
new file mode 100644
index 000000000000..9276e5207620
--- /dev/null
+++ b/arch/x86/vdso/vdso2c.h
@@ -0,0 +1,137 @@
+/*
+ * 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 int 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 + hdr->e_phoff);
+
+ /* Walk the segment table. */
+ for (i = 0; i < hdr->e_phnum; i++) {
+ if (pt[i].p_type == PT_LOAD) {
+ if (found_load)
+ fail("multiple PT_LOAD segs\n");
+
+ if (pt[i].p_offset != 0 || pt[i].p_vaddr != 0)
+ fail("PT_LOAD in wrong place\n");
+
+ if (pt[i].p_memsz != pt[i].p_filesz)
+ fail("cannot handle memsz != filesz\n");
+
+ load_size = pt[i].p_memsz;
+ found_load = 1;
+ } else if (pt[i].p_type == PT_DYNAMIC) {
+ dyn = addr + pt[i].p_offset;
+ dyn_end = addr + pt[i].p_offset + 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 && dyn[i].d_tag != DT_NULL; i++) {
+ if (dyn[i].d_tag == DT_REL || dyn[i].d_tag == DT_RELSZ ||
+ dyn[i].d_tag == DT_RELENT || dyn[i].d_tag == DT_TEXTREL)
+ fail("vdso image contains dynamic relocations\n");
+ }
+
+ /* Walk the section table */
+ secstrings_hdr = addr + hdr->e_shoff + hdr->e_shentsize*hdr->e_shstrndx;
+ secstrings = addr + secstrings_hdr->sh_offset;
+ for (i = 0; i < hdr->e_shnum; i++) {
+ Elf_Shdr *sh = addr + hdr->e_shoff + hdr->e_shentsize * i;
+ if (sh->sh_type == SHT_SYMTAB)
+ symtab_hdr = sh;
+
+ if (!strcmp(secstrings + sh->sh_name, ".altinstructions"))
+ alt_sec = sh;
+ }
+
+ if (!symtab_hdr) {
+ fail("no symbol table\n");
+ return 1;
+ }
+
+ strtab_hdr = addr + hdr->e_shoff +
+ hdr->e_shentsize * symtab_hdr->sh_link;
+
+ /* Walk the symbol table */
+ for (i = 0; i < symtab_hdr->sh_size / symtab_hdr->sh_entsize; i++) {
+ int k;
+ Elf_Sym *sym = addr + symtab_hdr->sh_offset +
+ symtab_hdr->sh_entsize * i;
+ const char *name = addr + strtab_hdr->sh_offset + 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] = sym->st_value;
+ }
+ }
+ }
+
+ /* Remove sections. */
+ hdr->e_shoff = 0;
+ hdr->e_shentsize = 0;
+ hdr->e_shnum = 0;
+ hdr->e_shstrndx = SHN_UNDEF;
+
+ if (!name) {
+ fwrite(addr, load_size, 1, outfile);
+ return 0;
+ }
+
+ 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.pages = pages,\n");
+ if (alt_sec) {
+ fprintf(outfile, "\t.alt = %lu,\n",
+ (unsigned long)alt_sec->sh_offset);
+ fprintf(outfile, "\t.alt_len = %lu,\n",
+ (unsigned long)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");
+
+ return 0;
+}