s390: remove 31 bit support

Remove the 31 bit support in order to reduce maintenance cost and
effectively remove dead code. Since a couple of years there is no
distribution left that comes with a 31 bit kernel.

The 31 bit kernel also has been broken since more than a year before
anybody noticed. In addition I added a removal warning to the kernel
shown at ipl for 5 minutes: a960062e5826 ("s390: add 31 bit warning
message") which let everybody know about the plan to remove 31 bit
code. We didn't get any response.

Given that the last 31 bit only machine was introduced in 1999 let's
remove the code.
Anybody with 31 bit user space code can still use the compat mode.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 1 insertions, 28 deletions

diff --git a/arch/s390/kernel/process.c b/arch/s390/kernel/process.c
index 13fc0978ca7e..dc5edc29b73a 100644
--- a/arch/s390/kernel/process.c
+++ b/arch/s390/kernel/process.c
@@ -79,13 +79,11 @@ void release_thread(struct task_struct *dead_task)
 {
 }
 
-#ifdef CONFIG_64BIT
 void arch_release_task_struct(struct task_struct *tsk)
 {
 	if (tsk->thread.vxrs)
 		kfree(tsk->thread.vxrs);
 }
-#endif
 
 int copy_thread(unsigned long clone_flags, unsigned long new_stackp,
 		unsigned long arg, struct task_struct *p)
@@ -144,19 +142,6 @@ int copy_thread(unsigned long clone_flags, unsigned long new_stackp,
 	p->thread.ri_signum = 0;
 	frame->childregs.psw.mask &= ~PSW_MASK_RI;
 
-#ifndef CONFIG_64BIT
-	/*
-	 * save fprs to current->thread.fp_regs to merge them with
-	 * the emulated registers and then copy the result to the child.
-	 */
-	save_fp_ctl(&current->thread.fp_regs.fpc);
-	save_fp_regs(current->thread.fp_regs.fprs);
-	memcpy(&p->thread.fp_regs, &current->thread.fp_regs,
-	       sizeof(s390_fp_regs));
-	/* Set a new TLS ?  */
-	if (clone_flags & CLONE_SETTLS)
-		p->thread.acrs[0] = frame->childregs.gprs[6];
-#else /* CONFIG_64BIT */
 	/* Save the fpu registers to new thread structure. */
 	save_fp_ctl(&p->thread.fp_regs.fpc);
 	save_fp_regs(p->thread.fp_regs.fprs);
@@ -172,15 +157,13 @@ int copy_thread(unsigned long clone_flags, unsigned long new_stackp,
 			p->thread.acrs[1] = (unsigned int)tls;
 		}
 	}
-#endif /* CONFIG_64BIT */
 	return 0;
 }
 
 asmlinkage void execve_tail(void)
 {
 	current->thread.fp_regs.fpc = 0;
-	if (MACHINE_HAS_IEEE)
-		asm volatile("sfpc %0,%0" : : "d" (0));
+	asm volatile("sfpc %0,%0" : : "d" (0));
 }
 
 /*
@@ -188,18 +171,8 @@ asmlinkage void execve_tail(void)
  */
 int dump_fpu (struct pt_regs * regs, s390_fp_regs *fpregs)
 {
-#ifndef CONFIG_64BIT
-	/*
-	 * save fprs to current->thread.fp_regs to merge them with
-	 * the emulated registers and then copy the result to the dump.
-	 */
-	save_fp_ctl(&current->thread.fp_regs.fpc);
-	save_fp_regs(current->thread.fp_regs.fprs);
-	memcpy(fpregs, &current->thread.fp_regs, sizeof(s390_fp_regs));
-#else /* CONFIG_64BIT */
 	save_fp_ctl(&fpregs->fpc);
 	save_fp_regs(fpregs->fprs);
-#endif /* CONFIG_64BIT */
 	return 1;
 }
 EXPORT_SYMBOL(dump_fpu);