Merge branch 'x86/vdso' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into next

Pull x86 cdso updates from Peter Anvin:
 "Vdso cleanups and improvements largely from Andy Lutomirski.  This
  makes the vdso a lot less ''special''"

* 'x86/vdso' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/vdso, build: Make LE access macros clearer, host-safe
  x86/vdso, build: Fix cross-compilation from big-endian architectures
  x86/vdso, build: When vdso2c fails, unlink the output
  x86, vdso: Fix an OOPS accessing the HPET mapping w/o an HPET
  x86, mm: Replace arch_vma_name with vm_ops->name for vsyscalls
  x86, mm: Improve _install_special_mapping and fix x86 vdso naming
  mm, fs: Add vm_ops->name as an alternative to arch_vma_name
  x86, vdso: Fix an OOPS accessing the HPET mapping w/o an HPET
  x86, vdso: Remove vestiges of VDSO_PRELINK and some outdated comments
  x86, vdso: Move the vvar and hpet mappings next to the 64-bit vDSO
  x86, vdso: Move the 32-bit vdso special pages after the text
  x86, vdso: Reimplement vdso.so preparation in build-time C
  x86, vdso: Move syscall and sysenter setup into kernel/cpu/common.c
  x86, vdso: Clean up 32-bit vs 64-bit vdso params
  x86, mm: Ensure correct alignment of the fixmap

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");
+}