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, 2 insertions, 151 deletions

diff --git a/arch/s390/kernel/traps.c b/arch/s390/kernel/traps.c
index f081cf1157c3..8be11c22ed17 100644
--- a/arch/s390/kernel/traps.c
+++ b/arch/s390/kernel/traps.c
@@ -26,7 +26,6 @@ int show_unhandled_signals = 1;
 
 static inline void __user *get_trap_ip(struct pt_regs *regs)
 {
-#ifdef CONFIG_64BIT
         unsigned long address;
 
         if (regs->int_code & 0x200)
@@ -35,10 +34,6 @@ static inline void __user *get_trap_ip(struct pt_regs *regs)
                 address = regs->psw.addr;
         return (void __user *)
                 ((address - (regs->int_code >> 16)) & PSW_ADDR_INSN);
-#else
-        return (void __user *)
-                ((regs->psw.addr - (regs->int_code >> 16)) & PSW_ADDR_INSN);
-#endif
 }
 
 static inline void report_user_fault(struct pt_regs *regs, int signr)
@@ -153,11 +148,8 @@ DO_ERROR_INFO(privileged_op, SIGILL, ILL_PRVOPC,
               "privileged operation")
 DO_ERROR_INFO(special_op_exception, SIGILL, ILL_ILLOPN,
               "special operation exception")
-
-#ifdef CONFIG_64BIT
 DO_ERROR_INFO(transaction_exception, SIGILL, ILL_ILLOPN,
               "transaction constraint exception")
-#endif
 
 static inline void do_fp_trap(struct pt_regs *regs, int fpc)
 {
@@ -211,29 +203,6 @@ void illegal_op(struct pt_regs *regs)
                 } else if (*((__u16 *) opcode) == UPROBE_SWBP_INSN) {
                         is_uprobe_insn = 1;
 #endif
-#ifdef CONFIG_MATHEMU
-                } else if (opcode[0] == 0xb3) {
-                        if (get_user(*((__u16 *) (opcode+2)), location+1))
-                                return;
-                        signal = math_emu_b3(opcode, regs);
-                } else if (opcode[0] == 0xed) {
-                        if (get_user(*((__u32 *) (opcode+2)),
-                                     (__u32 __user *)(location+1)))
-                                return;
-                        signal = math_emu_ed(opcode, regs);
-                } else if (*((__u16 *) opcode) == 0xb299) {
-                        if (get_user(*((__u16 *) (opcode+2)), location+1))
-                                return;
-                        signal = math_emu_srnm(opcode, regs);
-                } else if (*((__u16 *) opcode) == 0xb29c) {
-                        if (get_user(*((__u16 *) (opcode+2)), location+1))
-                                return;
-                        signal = math_emu_stfpc(opcode, regs);
-                } else if (*((__u16 *) opcode) == 0xb29d) {
-                        if (get_user(*((__u16 *) (opcode+2)), location+1))
-                                return;
-                        signal = math_emu_lfpc(opcode, regs);
-#endif
                 } else
                         signal = SIGILL;
         }
@@ -247,71 +216,14 @@ void illegal_op(struct pt_regs *regs)
                                3, SIGTRAP) != NOTIFY_STOP)
                         signal = SIGILL;
         }
-
-#ifdef CONFIG_MATHEMU
-        if (signal == SIGFPE)
-                do_fp_trap(regs, current->thread.fp_regs.fpc);
-        else if (signal == SIGSEGV)
-                do_trap(regs, signal, SEGV_MAPERR, "user address fault");
-        else
-#endif
         if (signal)
                 do_trap(regs, signal, ILL_ILLOPC, "illegal operation");
 }
 NOKPROBE_SYMBOL(illegal_op);
 
-#ifdef CONFIG_MATHEMU
-void specification_exception(struct pt_regs *regs)
-{
-        __u8 opcode[6];
-        __u16 __user *location = NULL;
-        int signal = 0;
-
-        location = (__u16 __user *) get_trap_ip(regs);
-
-        if (user_mode(regs)) {
-                get_user(*((__u16 *) opcode), location);
-                switch (opcode[0]) {
-                case 0x28: /* LDR Rx,Ry   */
-                        signal = math_emu_ldr(opcode);
-                        break;
-                case 0x38: /* LER Rx,Ry   */
-                        signal = math_emu_ler(opcode);
-                        break;
-                case 0x60: /* STD R,D(X,B) */
-                        get_user(*((__u16 *) (opcode+2)), location+1);
-                        signal = math_emu_std(opcode, regs);
-                        break;
-                case 0x68: /* LD R,D(X,B) */
-                        get_user(*((__u16 *) (opcode+2)), location+1);
-                        signal = math_emu_ld(opcode, regs);
-                        break;
-                case 0x70: /* STE R,D(X,B) */
-                        get_user(*((__u16 *) (opcode+2)), location+1);
-                        signal = math_emu_ste(opcode, regs);
-                        break;
-                case 0x78: /* LE R,D(X,B) */
-                        get_user(*((__u16 *) (opcode+2)), location+1);
-                        signal = math_emu_le(opcode, regs);
-                        break;
-                default:
-                        signal = SIGILL;
-                        break;
-                }
-        } else
-                signal = SIGILL;
-
-        if (signal == SIGFPE)
-                do_fp_trap(regs, current->thread.fp_regs.fpc);
-        else if (signal)
-                do_trap(regs, signal, ILL_ILLOPN, "specification exception");
-}
-#else
 DO_ERROR_INFO(specification_exception, SIGILL, ILL_ILLOPN,
               "specification exception");
-#endif
 
-#ifdef CONFIG_64BIT
 int alloc_vector_registers(struct task_struct *tsk)
 {
         __vector128 *vxrs;
@@ -377,7 +289,6 @@ static int __init disable_vector_extension(char *str)
         return 1;
 }
 __setup("novx", disable_vector_extension);
-#endif
 
 void data_exception(struct pt_regs *regs)
 {
@@ -386,65 +297,7 @@ void data_exception(struct pt_regs *regs)
 
         location = get_trap_ip(regs);
 
-        if (MACHINE_HAS_IEEE)
-                asm volatile("stfpc %0" : "=m" (current->thread.fp_regs.fpc));
-
-#ifdef CONFIG_MATHEMU
-        else if (user_mode(regs)) {
-                __u8 opcode[6];
-                get_user(*((__u16 *) opcode), location);
-                switch (opcode[0]) {
-                case 0x28: /* LDR Rx,Ry   */
-                        signal = math_emu_ldr(opcode);
-                        break;
-                case 0x38: /* LER Rx,Ry   */
-                        signal = math_emu_ler(opcode);
-                        break;
-                case 0x60: /* STD R,D(X,B) */
-                        get_user(*((__u16 *) (opcode+2)), location+1);
-                        signal = math_emu_std(opcode, regs);
-                        break;
-                case 0x68: /* LD R,D(X,B) */
-                        get_user(*((__u16 *) (opcode+2)), location+1);
-                        signal = math_emu_ld(opcode, regs);
-                        break;
-                case 0x70: /* STE R,D(X,B) */
-                        get_user(*((__u16 *) (opcode+2)), location+1);
-                        signal = math_emu_ste(opcode, regs);
-                        break;
-                case 0x78: /* LE R,D(X,B) */
-                        get_user(*((__u16 *) (opcode+2)), location+1);
-                        signal = math_emu_le(opcode, regs);
-                        break;
-                case 0xb3:
-                        get_user(*((__u16 *) (opcode+2)), location+1);
-                        signal = math_emu_b3(opcode, regs);
-                        break;
-                case 0xed:
-                        get_user(*((__u32 *) (opcode+2)),
-                                 (__u32 __user *)(location+1));
-                        signal = math_emu_ed(opcode, regs);
-                        break;
-                case 0xb2:
-                        if (opcode[1] == 0x99) {
-                                get_user(*((__u16 *) (opcode+2)), location+1);
-                                signal = math_emu_srnm(opcode, regs);
-                        } else if (opcode[1] == 0x9c) {
-                                get_user(*((__u16 *) (opcode+2)), location+1);
-                                signal = math_emu_stfpc(opcode, regs);
-                        } else if (opcode[1] == 0x9d) {
-                                get_user(*((__u16 *) (opcode+2)), location+1);
-                                signal = math_emu_lfpc(opcode, regs);
-                        } else
-                                signal = SIGILL;
-                        break;
-                default:
-                        signal = SIGILL;
-                        break;
-                }
-        }
-#endif 
-#ifdef CONFIG_64BIT
+        asm volatile("stfpc %0" : "=m" (current->thread.fp_regs.fpc));
         /* Check for vector register enablement */
         if (MACHINE_HAS_VX && !current->thread.vxrs &&
             (current->thread.fp_regs.fpc & FPC_DXC_MASK) == 0xfe00) {
@@ -454,13 +307,11 @@ void data_exception(struct pt_regs *regs)
                 clear_pt_regs_flag(regs, PIF_PER_TRAP);
                 return;
         }
-#endif
-
         if (current->thread.fp_regs.fpc & FPC_DXC_MASK)
                 signal = SIGFPE;
         else
                 signal = SIGILL;
-        if (signal == SIGFPE)
+        if (signal == SIGFPE)
                 do_fp_trap(regs, current->thread.fp_regs.fpc);
         else if (signal)
                 do_trap(regs, signal, ILL_ILLOPN, "data exception");