x86 vDSO: i386 vdso32

This makes the i386 kernel use the new vDSO build in arch/x86/vdso/vdso32/
to replace the old one from arch/x86/kernel/.

Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

11 files changed, 20 insertions, 129 deletions

diff --git a/arch/x86/Makefile_32 b/arch/x86/Makefile_32
index b152db71d5b5..9214224773ed 100644
--- a/arch/x86/Makefile_32
+++ b/arch/x86/Makefile_32
@@ -110,7 +110,8 @@ libs-y 					+= arch/x86/lib/
 core-y                                  += arch/x86/kernel/ \
                                            arch/x86/mm/ \
                                            $(mcore-y)/ \
-                                           arch/x86/crypto/
+                                           arch/x86/crypto/ \
+                                           arch/x86/vdso/
 drivers-$(CONFIG_MATH_EMULATION)        += arch/x86/math-emu/
 drivers-$(CONFIG_PCI)                   += arch/x86/pci/
 # must be linked after kernel/
diff --git a/arch/x86/kernel/Makefile_32 b/arch/x86/kernel/Makefile_32
index f7c1c1c88dda..0eef8226753b 100644
--- a/arch/x86/kernel/Makefile_32
+++ b/arch/x86/kernel/Makefile_32
@@ -33,7 +33,7 @@ obj-$(CONFIG_X86_NUMAQ)		+= numaq_32.o
 obj-$(CONFIG_X86_SUMMIT_NUMA)   += summit_32.o
 obj-$(CONFIG_KPROBES)           += kprobes_32.o
 obj-$(CONFIG_MODULES)           += module_32.o
-obj-y                           += sysenter_32.o vsyscall_32.o
+obj-y                           += sysenter_32.o
 obj-$(CONFIG_ACPI_SRAT)         += srat_32.o
 obj-$(CONFIG_EFI)               += efi_32.o efi_stub_32.o
 obj-$(CONFIG_DOUBLEFAULT)       += doublefault_32.o
@@ -48,44 +48,3 @@ obj-$(CONFIG_PARAVIRT)		+= paravirt_32.o
 obj-y                           += pcspeaker.o
 
 obj-$(CONFIG_SCx200)            += scx200_32.o
-
-# vsyscall_32.o contains the vsyscall DSO images as __initdata.
-# We must build both images before we can assemble it.
-# Note: kbuild does not track this dependency due to usage of .incbin
-$(obj)/vsyscall_32.o: $(obj)/vsyscall-int80_32.so $(obj)/vsyscall-sysenter_32.so
-targets += $(foreach F,int80 sysenter,vsyscall-$F_32.o vsyscall-$F_32.so)
-targets += vsyscall-note_32.o vsyscall_32.lds
-
-$(obj)/vsyscall-%_32.o: $(src)/../vdso/vdso32/%.S
-        $(call if_changed_dep,as_o_S)
-
-# The DSO images are built using a special linker script.
-quiet_cmd_syscall = SYSCALL $@
-      cmd_syscall = $(CC) -m elf_i386 -nostdlib $(SYSCFLAGS_$(@F)) \
-                          -Wl,-T,$(filter-out FORCE,$^) -o $@
-
-export CPPFLAGS_vsyscall_32.lds += -P -C -Ui386
-
-vsyscall-flags = -shared -s -Wl,-soname=linux-gate.so.1 \
-                 $(call ld-option, -Wl$(comma)--hash-style=sysv)
-SYSCFLAGS_vsyscall-sysenter_32.so       = $(vsyscall-flags)
-SYSCFLAGS_vsyscall-int80_32.so  = $(vsyscall-flags)
-
-$(obj)/vsyscall-int80_32.so $(obj)/vsyscall-sysenter_32.so: \
-$(obj)/vsyscall-%.so: $(src)/vsyscall_32.lds \
-                      $(obj)/vsyscall-%.o $(obj)/vsyscall-note_32.o FORCE
-        $(call if_changed,syscall)
-
-# We also create a special relocatable object that should mirror the symbol
-# table and layout of the linked DSO.  With ld -R we can then refer to
-# these symbols in the kernel code rather than hand-coded addresses.
-extra-y += vsyscall-syms.o
-$(obj)/built-in.o: $(obj)/vsyscall-syms.o
-$(obj)/built-in.o: ld_flags += -R $(obj)/vsyscall-syms.o
-
-SYSCFLAGS_vsyscall-syms.o = -r
-$(obj)/vsyscall-syms.o: $(src)/vsyscall_32.lds \
-                        $(obj)/vsyscall-sysenter_32.o $(obj)/vsyscall-note_32.o FORCE
-        $(call if_changed,syscall)
-
-
diff --git a/arch/x86/kernel/asm-offsets_32.c b/arch/x86/kernel/asm-offsets_32.c
index 4f750ec810f6..fd7464d23339 100644
--- a/arch/x86/kernel/asm-offsets_32.c
+++ b/arch/x86/kernel/asm-offsets_32.c
@@ -111,8 +111,6 @@ void foo(void)
         DEFINE(PTRS_PER_PMD, PTRS_PER_PMD);
         DEFINE(PTRS_PER_PGD, PTRS_PER_PGD);
 
-        DEFINE(VDSO_PRELINK_asm, VDSO_PRELINK);
-
         OFFSET(crypto_tfm_ctx_offset, crypto_tfm, __crt_ctx);
 
 #ifdef CONFIG_PARAVIRT
diff --git a/arch/x86/kernel/signal_32.c b/arch/x86/kernel/signal_32.c
index 5c6170c44b00..1ac53e9a0859 100644
--- a/arch/x86/kernel/signal_32.c
+++ b/arch/x86/kernel/signal_32.c
@@ -23,6 +23,7 @@
 #include <asm/ucontext.h>
 #include <asm/uaccess.h>
 #include <asm/i387.h>
+#include <asm/vdso.h>
 #include "sigframe_32.h"
 
 #define DEBUG_SIG 0
@@ -362,7 +363,7 @@ static int setup_frame(int sig, struct k_sigaction *ka,
         }
 
         if (current->binfmt->hasvdso)
-                restorer = (void *)VDSO_SYM(&__kernel_sigreturn);
+                restorer = VDSO32_SYMBOL(current->mm->context.vdso, sigreturn);
         else
                 restorer = (void *)&frame->retcode;
         if (ka->sa.sa_flags & SA_RESTORER)
@@ -459,7 +460,7 @@ static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
                 goto give_sigsegv;
 
         /* Set up to return from userspace.  */
-        restorer = (void *)VDSO_SYM(&__kernel_rt_sigreturn);
+        restorer = VDSO32_SYMBOL(current->mm->context.vdso, rt_sigreturn);
         if (ka->sa.sa_flags & SA_RESTORER)
                 restorer = ka->sa.sa_restorer;
         err |= __put_user(restorer, &frame->pretcode);
diff --git a/arch/x86/kernel/sysenter_32.c b/arch/x86/kernel/sysenter_32.c
index 5a2d951e2608..85c52d23ee40 100644
--- a/arch/x86/kernel/sysenter_32.c
+++ b/arch/x86/kernel/sysenter_32.c
@@ -23,6 +23,7 @@
 #include <asm/unistd.h>
 #include <asm/elf.h>
 #include <asm/tlbflush.h>
+#include <asm/vdso.h>
 
 enum {
         VDSO_DISABLED = 0,
@@ -259,9 +260,6 @@ int __init sysenter_setup(void)
         return 0;
 }
 
-/* Defined in vsyscall-sysenter.S */
-extern void SYSENTER_RETURN;
-
 /* Setup a VMA at program startup for the vsyscall page */
 int arch_setup_additional_pages(struct linux_binprm *bprm, int exstack)
 {
@@ -308,7 +306,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int exstack)
 
         current->mm->context.vdso = (void *)addr;
         current_thread_info()->sysenter_return =
-                (void *)VDSO_SYM(&SYSENTER_RETURN);
+                VDSO32_SYMBOL(addr, SYSENTER_RETURN);
 
   up_fail:
         up_write(&mm->mmap_sem);
diff --git a/arch/x86/kernel/vsyscall_32.lds.S b/arch/x86/kernel/vsyscall_32.lds.S
deleted file mode 100644
index 4a8b0ed9b8fb..000000000000
--- a/arch/x86/kernel/vsyscall_32.lds.S
+++ /dev/null
@@ -1,67 +0,0 @@
-/*
- * Linker script for vsyscall DSO.  The vsyscall page is an ELF shared
- * object prelinked to its virtual address, and with only one read-only
- * segment (that fits in one page).  This script controls its layout.
- */
-#include <asm/asm-offsets.h>
-
-SECTIONS
-{
-  . = VDSO_PRELINK_asm + SIZEOF_HEADERS;
-
-  .hash           : { *(.hash) }                :text
-  .gnu.hash       : { *(.gnu.hash) }
-  .dynsym         : { *(.dynsym) }
-  .dynstr         : { *(.dynstr) }
-  .gnu.version    : { *(.gnu.version) }
-  .gnu.version_d  : { *(.gnu.version_d) }
-  .gnu.version_r  : { *(.gnu.version_r) }
-
-  /* This linker script is used both with -r and with -shared.
-     For the layouts to match, we need to skip more than enough
-     space for the dynamic symbol table et al.  If this amount
-     is insufficient, ld -shared will barf.  Just increase it here.  */
-  . = VDSO_PRELINK_asm + 0x400;
-
-  .text           : { *(.text) }                :text =0x90909090
-  .note           : { *(.note.*) }              :text :note
-  .eh_frame_hdr   : { *(.eh_frame_hdr) }        :text :eh_frame_hdr
-  .eh_frame       : { KEEP (*(.eh_frame)) }     :text
-  .dynamic        : { *(.dynamic) }             :text :dynamic
-  .useless        : {
-        *(.got.plt) *(.got)
-        *(.data .data.* .gnu.linkonce.d.*)
-        *(.dynbss)
-        *(.bss .bss.* .gnu.linkonce.b.*)
-  }                                             :text
-}
-
-/*
- * We must supply the ELF program headers explicitly to get just one
- * PT_LOAD segment, and set the flags explicitly to make segments read-only.
- */
-PHDRS
-{
-  text PT_LOAD FILEHDR PHDRS FLAGS(5); /* PF_R|PF_X */
-  dynamic PT_DYNAMIC FLAGS(4); /* PF_R */
-  note PT_NOTE FLAGS(4); /* PF_R */
-  eh_frame_hdr 0x6474e550; /* PT_GNU_EH_FRAME, but ld doesn't match the name */
-}
-
-/*
- * This controls what symbols we export from the DSO.
- */
-VERSION
-{
-  LINUX_2.5 {
-    global:
-        __kernel_vsyscall;
-        __kernel_sigreturn;
-        __kernel_rt_sigreturn;
-
-    local: *;
-  };
-}
-
-/* The ELF entry point can be used to set the AT_SYSINFO value.  */
-ENTRY(__kernel_vsyscall);
diff --git a/arch/x86/vdso/Makefile b/arch/x86/vdso/Makefile
index a02e1ca2a1bc..ca2aabf8ed39 100644
--- a/arch/x86/vdso/Makefile
+++ b/arch/x86/vdso/Makefile
@@ -14,7 +14,8 @@ vdso-install-$(VDSO32-y)	+= $(vdso32-y:=.so)
 vobjs-y := vdso-note.o vclock_gettime.o vgetcpu.o vvar.o
 
 # files to link into kernel
-obj-y := vma.o vdso.o
+obj-$(VDSO64-y)                 += vma.o vdso.o
+obj-$(CONFIG_X86_32)            += vdso32.o
 
 vobjs := $(foreach F,$(vobjs-y),$(obj)/$F)
 
@@ -52,7 +53,7 @@ $(obj)/vclock_gettime.o: KBUILD_CFLAGS = $(CFL)
 $(obj)/vgetcpu.o: KBUILD_CFLAGS = $(CFL)
 
 targets += vdso-syms.lds
-obj-y += vdso-syms.lds
+obj-$(VDSO64-y)                 += vdso-syms.lds
 
 #
 # Match symbols in the DSO that look like VDSO*; produce a file of constants.
@@ -68,6 +69,7 @@ $(obj)/%-syms.lds: $(obj)/%.so.dbg FORCE
 #
 # Build multiple 32-bit vDSO images to choose from at boot time.
 #
+obj-$(VDSO32-y)                 += vdso32-syms.lds
 vdso32.so-$(CONFIG_X86_32)      += int80
 vdso32.so-$(VDSO32-y)           += sysenter
 
@@ -84,6 +86,8 @@ targets += vdso32/note.o $(vdso32.so-y:%=vdso32/%.o)
 
 extra-y += $(vdso32.so-y:%=vdso32-%.so)
 
+$(obj)/vdso32.o: $(vdso32.so-y:%=$(obj)/vdso32-%.so)
+
 KBUILD_AFLAGS_32 := $(filter-out -m64,$(KBUILD_AFLAGS))
 $(vdso32.so-y:%=$(obj)/vdso32-%.so.dbg): KBUILD_AFLAGS = $(KBUILD_AFLAGS_32)
 $(vdso32.so-y:%=$(obj)/vdso32-%.so.dbg): asflags-$(CONFIG_X86_64) += -m32
diff --git a/arch/x86/kernel/vsyscall_32.S b/arch/x86/vdso/vdso32.S
index a5ab3dc4fd25..cab020c99c3d 100644
--- a/arch/x86/kernel/vsyscall_32.S
+++ b/arch/x86/vdso/vdso32.S
@@ -4,12 +4,12 @@ __INITDATA
 
         .globl vsyscall_int80_start, vsyscall_int80_end
 vsyscall_int80_start:
-        .incbin "arch/x86/kernel/vsyscall-int80_32.so"
+        .incbin "arch/x86/vdso/vdso32-int80.so"
 vsyscall_int80_end:
 
         .globl vsyscall_sysenter_start, vsyscall_sysenter_end
 vsyscall_sysenter_start:
-        .incbin "arch/x86/kernel/vsyscall-sysenter_32.so"
+        .incbin "arch/x86/vdso/vdso32-sysenter.so"
 vsyscall_sysenter_end:
 
 __FINIT
diff --git a/arch/x86/vdso/vdso32/note.S b/arch/x86/vdso/vdso32/note.S
index 0cf934f2633e..c83f25734696 100644
--- a/arch/x86/vdso/vdso32/note.S
+++ b/arch/x86/vdso/vdso32/note.S
@@ -35,10 +35,9 @@ ELFNOTE_END
 
 #include "../../xen/vdso.h"     /* Defines VDSO_NOTE_NONEGSEG_BIT.  */
 
-        .globl VDSO_NOTE_MASK
 ELFNOTE_START(GNU, 2, "a")
         .long 1                 /* ncaps */
-VDSO_NOTE_MASK:
+VDSO32_NOTE_MASK:               /* Symbol used by arch/x86/xen/setup.c */
         .long 0                 /* mask */
         .byte VDSO_NOTE_NONEGSEG_BIT; .asciz "nosegneg" /* bit, name */
 ELFNOTE_END
diff --git a/arch/x86/vdso/vdso32/sysenter.S b/arch/x86/vdso/vdso32/sysenter.S
index 4b98fc41d3e0..109bfa394eaa 100644
--- a/arch/x86/vdso/vdso32/sysenter.S
+++ b/arch/x86/vdso/vdso32/sysenter.S
@@ -45,8 +45,7 @@ __kernel_vsyscall:
         /* 14: System call restart point is here! (SYSENTER_RETURN-2) */
         jmp .Lenter_kernel
         /* 16: System call normal return point is here! */
-        .globl SYSENTER_RETURN  /* Symbol used by sysenter.c  */
-SYSENTER_RETURN:
+VDSO32_SYSENTER_RETURN: /* Symbol used by sysenter.c via vdso32-syms.h */
         pop %ebp
 .Lpop_ebp:
         pop %edx
diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c
index f84e77226646..fd91568090f4 100644
--- a/arch/x86/xen/setup.c
+++ b/arch/x86/xen/setup.c
@@ -10,6 +10,7 @@
 #include <linux/pm.h>
 
 #include <asm/elf.h>
+#include <asm/vdso.h>
 #include <asm/e820.h>
 #include <asm/setup.h>
 #include <asm/xen/hypervisor.h>
@@ -61,10 +62,8 @@ static void xen_idle(void)
  */
 static void fiddle_vdso(void)
 {
-        extern u32 VDSO_NOTE_MASK; /* See ../kernel/vsyscall-note.S.  */
         extern char vsyscall_int80_start;
-        u32 *mask = (u32 *) ((unsigned long) &VDSO_NOTE_MASK - VDSO_PRELINK +
-                             &vsyscall_int80_start);
+        u32 *mask = VDSO32_SYMBOL(&vsyscall_int80_start, NOTE_MASK);
         *mask |= 1 << VDSO_NOTE_NONEGSEG_BIT;
 }