MIPS: Factor o32 specific code into signal_o32.c

The commit ebb5e78cc634 ("MIPS: Initial implementation of a VDSO")
caused building a 64 bit kernel with support for n32 and not o32
to produce a build error:

arch/mips/kernel/signal32.c:415:11: error: ‘vdso_image_o32’ undeclared here (not in a function)
  .vdso  = &vdso_image_o32,

Fix this by moving the o32 specific code into signal_o32.c and
updating the Makefile accordingly.

Signed-off-by: Harvey Hunt <harvey.hunt@imgtec.com>
Cc: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: Alex Smith <alex@alex-smith.me.uk>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/13690/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/kernel/signal32.c b/arch/mips/kernel/signal32.c
index 78c8349..97b7c51 100644
--- a/arch/mips/kernel/signal32.c
+++ b/arch/mips/kernel/signal32.c
@@ -6,129 +6,26 @@
  * Copyright (C) 1991, 1992  Linus Torvalds
  * Copyright (C) 1994 - 2000, 2006  Ralf Baechle
  * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
+ * Copyright (C) 2016, Imagination Technologies Ltd.
  */
-#include <linux/cache.h>
-#include <linux/compat.h>
-#include <linux/sched.h>
-#include <linux/mm.h>
-#include <linux/smp.h>
+#include <linux/compiler.h>
+#include <linux/errno.h>
 #include <linux/kernel.h>
 #include <linux/signal.h>
 #include <linux/syscalls.h>
-#include <linux/errno.h>
-#include <linux/wait.h>
-#include <linux/ptrace.h>
-#include <linux/suspend.h>
-#include <linux/compiler.h>
-#include <linux/uaccess.h>
 
-#include <asm/abi.h>
-#include <asm/asm.h>
+#include <asm/compat.h>
 #include <asm/compat-signal.h>
-#include <linux/bitops.h>
-#include <asm/cacheflush.h>
-#include <asm/sim.h>
-#include <asm/ucontext.h>
-#include <asm/fpu.h>
-#include <asm/war.h>
-#include <asm/dsp.h>
+#include <asm/uaccess.h>
+#include <asm/unistd.h>
 
 #include "signal-common.h"
 
-/*
- * Including <asm/unistd.h> would give use the 64-bit syscall numbers ...
- */
-#define __NR_O32_restart_syscall	4253
-
 /* 32-bit compatibility types */
 
 typedef unsigned int __sighandler32_t;
 typedef void (*vfptr_t)(void);
 
-struct ucontext32 {
-	u32		    uc_flags;
-	s32		    uc_link;
-	compat_stack_t      uc_stack;
-	struct sigcontext32 uc_mcontext;
-	compat_sigset_t	    uc_sigmask;	  /* mask last for extensibility */
-};
-
-struct sigframe32 {
-	u32 sf_ass[4];		/* argument save space for o32 */
-	u32 sf_pad[2];		/* Was: signal trampoline */
-	struct sigcontext32 sf_sc;
-	compat_sigset_t sf_mask;
-};
-
-struct rt_sigframe32 {
-	u32 rs_ass[4];			/* argument save space for o32 */
-	u32 rs_pad[2];			/* Was: signal trampoline */
-	compat_siginfo_t rs_info;
-	struct ucontext32 rs_uc;
-};
-
-static int setup_sigcontext32(struct pt_regs *regs,
-			      struct sigcontext32 __user *sc)
-{
-	int err = 0;
-	int i;
-
-	err |= __put_user(regs->cp0_epc, &sc->sc_pc);
-
-	err |= __put_user(0, &sc->sc_regs[0]);
-	for (i = 1; i < 32; i++)
-		err |= __put_user(regs->regs[i], &sc->sc_regs[i]);
-
-	err |= __put_user(regs->hi, &sc->sc_mdhi);
-	err |= __put_user(regs->lo, &sc->sc_mdlo);
-	if (cpu_has_dsp) {
-		err |= __put_user(rddsp(DSP_MASK), &sc->sc_dsp);
-		err |= __put_user(mfhi1(), &sc->sc_hi1);
-		err |= __put_user(mflo1(), &sc->sc_lo1);
-		err |= __put_user(mfhi2(), &sc->sc_hi2);
-		err |= __put_user(mflo2(), &sc->sc_lo2);
-		err |= __put_user(mfhi3(), &sc->sc_hi3);
-		err |= __put_user(mflo3(), &sc->sc_lo3);
-	}
-
-	/*
-	 * Save FPU state to signal context.  Signal handler
-	 * will "inherit" current FPU state.
-	 */
-	err |= protected_save_fp_context(sc);
-
-	return err;
-}
-
-static int restore_sigcontext32(struct pt_regs *regs,
-				struct sigcontext32 __user *sc)
-{
-	int err = 0;
-	s32 treg;
-	int i;
-
-	/* Always make any pending restarted system calls return -EINTR */
-	current->restart_block.fn = do_no_restart_syscall;
-
-	err |= __get_user(regs->cp0_epc, &sc->sc_pc);
-	err |= __get_user(regs->hi, &sc->sc_mdhi);
-	err |= __get_user(regs->lo, &sc->sc_mdlo);
-	if (cpu_has_dsp) {
-		err |= __get_user(treg, &sc->sc_hi1); mthi1(treg);
-		err |= __get_user(treg, &sc->sc_lo1); mtlo1(treg);
-		err |= __get_user(treg, &sc->sc_hi2); mthi2(treg);
-		err |= __get_user(treg, &sc->sc_lo2); mtlo2(treg);
-		err |= __get_user(treg, &sc->sc_hi3); mthi3(treg);
-		err |= __get_user(treg, &sc->sc_lo3); mtlo3(treg);
-		err |= __get_user(treg, &sc->sc_dsp); wrdsp(treg, DSP_MASK);
-	}
-
-	for (i = 1; i < 32; i++)
-		err |= __get_user(regs->regs[i], &sc->sc_regs[i]);
-
-	return err ?: protected_restore_fp_context(sc);
-}
-
 /*
  * Atomically swap in the new signal mask, and wait for a signal.
  */
@@ -247,176 +144,3 @@
 
 	return 0;
 }
-
-asmlinkage void sys32_sigreturn(nabi_no_regargs struct pt_regs regs)
-{
-	struct sigframe32 __user *frame;
-	sigset_t blocked;
-	int sig;
-
-	frame = (struct sigframe32 __user *) regs.regs[29];
-	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
-		goto badframe;
-	if (__copy_conv_sigset_from_user(&blocked, &frame->sf_mask))
-		goto badframe;
-
-	set_current_blocked(&blocked);
-
-	sig = restore_sigcontext32(&regs, &frame->sf_sc);
-	if (sig < 0)
-		goto badframe;
-	else if (sig)
-		force_sig(sig, current);
-
-	/*
-	 * Don't let your children do this ...
-	 */
-	__asm__ __volatile__(
-		"move\t$29, %0\n\t"
-		"j\tsyscall_exit"
-		:/* no outputs */
-		:"r" (&regs));
-	/* Unreached */
-
-badframe:
-	force_sig(SIGSEGV, current);
-}
-
-asmlinkage void sys32_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
-{
-	struct rt_sigframe32 __user *frame;
-	sigset_t set;
-	int sig;
-
-	frame = (struct rt_sigframe32 __user *) regs.regs[29];
-	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
-		goto badframe;
-	if (__copy_conv_sigset_from_user(&set, &frame->rs_uc.uc_sigmask))
-		goto badframe;
-
-	set_current_blocked(&set);
-
-	sig = restore_sigcontext32(&regs, &frame->rs_uc.uc_mcontext);
-	if (sig < 0)
-		goto badframe;
-	else if (sig)
-		force_sig(sig, current);
-
-	if (compat_restore_altstack(&frame->rs_uc.uc_stack))
-		goto badframe;
-
-	/*
-	 * Don't let your children do this ...
-	 */
-	__asm__ __volatile__(
-		"move\t$29, %0\n\t"
-		"j\tsyscall_exit"
-		:/* no outputs */
-		:"r" (&regs));
-	/* Unreached */
-
-badframe:
-	force_sig(SIGSEGV, current);
-}
-
-static int setup_frame_32(void *sig_return, struct ksignal *ksig,
-			  struct pt_regs *regs, sigset_t *set)
-{
-	struct sigframe32 __user *frame;
-	int err = 0;
-
-	frame = get_sigframe(ksig, regs, sizeof(*frame));
-	if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
-		return -EFAULT;
-
-	err |= setup_sigcontext32(regs, &frame->sf_sc);
-	err |= __copy_conv_sigset_to_user(&frame->sf_mask, set);
-
-	if (err)
-		return -EFAULT;
-
-	/*
-	 * Arguments to signal handler:
-	 *
-	 *   a0 = signal number
-	 *   a1 = 0 (should be cause)
-	 *   a2 = pointer to struct sigcontext
-	 *
-	 * $25 and c0_epc point to the signal handler, $29 points to the
-	 * struct sigframe.
-	 */
-	regs->regs[ 4] = ksig->sig;
-	regs->regs[ 5] = 0;
-	regs->regs[ 6] = (unsigned long) &frame->sf_sc;
-	regs->regs[29] = (unsigned long) frame;
-	regs->regs[31] = (unsigned long) sig_return;
-	regs->cp0_epc = regs->regs[25] = (unsigned long) ksig->ka.sa.sa_handler;
-
-	DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
-	       current->comm, current->pid,
-	       frame, regs->cp0_epc, regs->regs[31]);
-
-	return 0;
-}
-
-static int setup_rt_frame_32(void *sig_return, struct ksignal *ksig,
-			     struct pt_regs *regs, sigset_t *set)
-{
-	struct rt_sigframe32 __user *frame;
-	int err = 0;
-
-	frame = get_sigframe(ksig, regs, sizeof(*frame));
-	if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
-		return -EFAULT;
-
-	/* Convert (siginfo_t -> compat_siginfo_t) and copy to user. */
-	err |= copy_siginfo_to_user32(&frame->rs_info, &ksig->info);
-
-	/* Create the ucontext.	 */
-	err |= __put_user(0, &frame->rs_uc.uc_flags);
-	err |= __put_user(0, &frame->rs_uc.uc_link);
-	err |= __compat_save_altstack(&frame->rs_uc.uc_stack, regs->regs[29]);
-	err |= setup_sigcontext32(regs, &frame->rs_uc.uc_mcontext);
-	err |= __copy_conv_sigset_to_user(&frame->rs_uc.uc_sigmask, set);
-
-	if (err)
-		return -EFAULT;
-
-	/*
-	 * Arguments to signal handler:
-	 *
-	 *   a0 = signal number
-	 *   a1 = 0 (should be cause)
-	 *   a2 = pointer to ucontext
-	 *
-	 * $25 and c0_epc point to the signal handler, $29 points to
-	 * the struct rt_sigframe32.
-	 */
-	regs->regs[ 4] = ksig->sig;
-	regs->regs[ 5] = (unsigned long) &frame->rs_info;
-	regs->regs[ 6] = (unsigned long) &frame->rs_uc;
-	regs->regs[29] = (unsigned long) frame;
-	regs->regs[31] = (unsigned long) sig_return;
-	regs->cp0_epc = regs->regs[25] = (unsigned long) ksig->ka.sa.sa_handler;
-
-	DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
-	       current->comm, current->pid,
-	       frame, regs->cp0_epc, regs->regs[31]);
-
-	return 0;
-}
-
-/*
- * o32 compatibility on 64-bit kernels, without DSP ASE
- */
-struct mips_abi mips_abi_32 = {
-	.setup_frame	= setup_frame_32,
-	.setup_rt_frame = setup_rt_frame_32,
-	.restart	= __NR_O32_restart_syscall,
-
-	.off_sc_fpregs = offsetof(struct sigcontext32, sc_fpregs),
-	.off_sc_fpc_csr = offsetof(struct sigcontext32, sc_fpc_csr),
-	.off_sc_used_math = offsetof(struct sigcontext32, sc_used_math),
-
-	.vdso		= &vdso_image_o32,
-};