Patchwork [07/12] linux-user: S/390 64-bit (s390x) support

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Submitter Ulrich Hecht
Date Oct. 21, 2009, 1:52 p.m.
Message ID <1256133153-3121-8-git-send-email-uli@suse.de>
Download mbox | patch
Permalink /patch/36609/
State New
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Ulrich Hecht - Oct. 21, 2009, 1:52 p.m.
code for running 64-bit S/390 Linux binaries

use CPU_DoubleU for FP regs
proper specification exception (SIGILL) handling

Signed-off-by: Ulrich Hecht <uli@suse.de>
---
 linux-user/elfload.c             |   18 ++
 linux-user/main.c                |   89 ++++++++++
 linux-user/s390x/syscall.h       |   25 +++
 linux-user/s390x/syscall_nr.h    |  348 ++++++++++++++++++++++++++++++++++++++
 linux-user/s390x/target_signal.h |   26 +++
 linux-user/s390x/termbits.h      |  283 +++++++++++++++++++++++++++++++
 linux-user/signal.c              |  314 ++++++++++++++++++++++++++++++++++
 linux-user/syscall.c             |   16 ++-
 linux-user/syscall_defs.h        |   56 ++++++-
 qemu-binfmt-conf.sh              |    5 +-
 10 files changed, 1173 insertions(+), 7 deletions(-)
 create mode 100644 linux-user/s390x/syscall.h
 create mode 100644 linux-user/s390x/syscall_nr.h
 create mode 100644 linux-user/s390x/target_signal.h
 create mode 100644 linux-user/s390x/termbits.h

Patch

diff --git a/linux-user/elfload.c b/linux-user/elfload.c
index 62a3f2a..90e9268 100644
--- a/linux-user/elfload.c
+++ b/linux-user/elfload.c
@@ -679,6 +679,24 @@  static inline void init_thread(struct target_pt_regs *regs, struct image_info *i
 
 #endif /* TARGET_ALPHA */
 
+#ifdef TARGET_S390X
+
+#define ELF_START_MMAP (0x20000000000ULL)
+
+#define elf_check_arch(x) ( (x) == ELF_ARCH )
+
+#define ELF_CLASS	ELFCLASS64
+#define ELF_DATA	ELFDATA2MSB
+#define ELF_ARCH	EM_S390
+
+static inline void init_thread(struct target_pt_regs *regs, struct image_info *infop)
+{
+    regs->psw.addr = infop->entry;
+    regs->gprs[15] = infop->start_stack;
+}
+
+#endif /* TARGET_S390X */
+
 #ifndef ELF_PLATFORM
 #define ELF_PLATFORM (NULL)
 #endif
diff --git a/linux-user/main.c b/linux-user/main.c
index 81a1ada..798b2d5 100644
--- a/linux-user/main.c
+++ b/linux-user/main.c
@@ -2351,6 +2351,86 @@  void cpu_loop (CPUState *env)
 }
 #endif /* TARGET_ALPHA */
 
+#ifdef TARGET_S390X
+void cpu_loop(CPUS390XState *env)
+{
+    int trapnr;
+    target_siginfo_t info;
+
+    while (1) {
+        trapnr = cpu_s390x_exec (env);
+        
+        if ((trapnr & 0xffff0000) == EXCP_EXECUTE_SVC) {
+            int n = trapnr & 0xffff;
+            env->regs[2] = do_syscall(env, n,
+                       env->regs[2],
+                       env->regs[3],
+                       env->regs[4],
+                       env->regs[5],
+                       env->regs[6],
+                       env->regs[7]);
+        }
+        else switch (trapnr) {
+        case EXCP_INTERRUPT:
+            /* just indicate that signals should be handled asap */
+            break;
+        case EXCP_DEBUG:
+            {
+                int sig;
+
+                sig = gdb_handlesig (env, TARGET_SIGTRAP);
+                if (sig) {
+                    info.si_signo = sig;
+                    info.si_errno = 0;
+                    info.si_code = TARGET_TRAP_BRKPT;
+                    queue_signal(env, info.si_signo, &info);
+                }
+            }
+            break;
+        case EXCP_SVC:
+            {
+                int n = ldub(env->psw.addr - 1);
+                if (!n) n = env->regs[1];	/* syscalls > 255 */
+                env->regs[2] = do_syscall(env, n,
+                           env->regs[2],
+                           env->regs[3],
+                           env->regs[4],
+                           env->regs[5],
+                           env->regs[6],
+                           env->regs[7]);
+            }
+            break;
+        case EXCP_ADDR:
+            {
+                info.si_signo = SIGSEGV;
+                info.si_errno = 0;
+                /* XXX: check env->error_code */
+                info.si_code = TARGET_SEGV_MAPERR;
+                info._sifields._sigfault._addr = env->__excp_addr;
+                queue_signal(env, info.si_signo, &info);
+            }
+            break;
+        case EXCP_SPEC:
+            {
+                fprintf(stderr,"specification exception insn 0x%08x%04x\n", ldl(env->psw.addr), lduw(env->psw.addr + 4));
+                info.si_signo = SIGILL;
+                info.si_errno = 0;
+                info.si_code = TARGET_ILL_ILLOPC;
+                info._sifields._sigfault._addr = env->__excp_addr;
+                queue_signal(env, info.si_signo, &info);
+            }
+            break;
+        default:
+            printf ("Unhandled trap: 0x%x\n", trapnr);
+            cpu_dump_state(env, stderr, fprintf, 0);
+            exit (1);
+        }
+        process_pending_signals (env);
+    }
+}
+
+#endif /* TARGET_S390X */
+
 static void usage(void)
 {
     printf("qemu-" TARGET_ARCH " version " QEMU_VERSION QEMU_PKGVERSION ", Copyright (c) 2003-2008 Fabrice Bellard\n"
@@ -2987,6 +3067,15 @@  int main(int argc, char **argv, char **envp)
 	    env->regs[15] = regs->acr;	    
 	    env->pc = regs->erp;
     }
+#elif defined(TARGET_S390X)
+    {
+            int i;
+            for (i = 0; i < 16; i++) {
+                env->regs[i] = regs->gprs[i];
+            }
+            env->psw.mask = regs->psw.mask;
+            env->psw.addr = regs->psw.addr;
+    }
 #else
 #error unsupported target CPU
 #endif
diff --git a/linux-user/s390x/syscall.h b/linux-user/s390x/syscall.h
new file mode 100644
index 0000000..a3812a8
--- /dev/null
+++ b/linux-user/s390x/syscall.h
@@ -0,0 +1,25 @@ 
+/* this typedef defines how a Program Status Word looks like */
+typedef struct
+{
+    abi_ulong mask;
+    abi_ulong addr;
+} __attribute__ ((aligned(8))) target_psw_t;
+
+/*
+ * The pt_regs struct defines the way the registers are stored on
+ * the stack during a system call.
+ */
+
+#define TARGET_NUM_GPRS        16
+
+struct target_pt_regs
+{
+    abi_ulong args[1];
+    target_psw_t psw;
+    abi_ulong gprs[TARGET_NUM_GPRS];
+    abi_ulong orig_gpr2;
+    unsigned short ilc;
+    unsigned short trap;
+};
+
+#define UNAME_MACHINE "s390x"
diff --git a/linux-user/s390x/syscall_nr.h b/linux-user/s390x/syscall_nr.h
new file mode 100644
index 0000000..4a60b9a
--- /dev/null
+++ b/linux-user/s390x/syscall_nr.h
@@ -0,0 +1,348 @@ 
+/*
+ * This file contains the system call numbers.
+ */
+
+#define TARGET_NR_exit                 1
+#define TARGET_NR_fork                 2
+#define TARGET_NR_read                 3
+#define TARGET_NR_write                4
+#define TARGET_NR_open                 5
+#define TARGET_NR_close                6
+#define TARGET_NR_restart_syscall	  7
+#define TARGET_NR_creat                8
+#define TARGET_NR_link                 9
+#define TARGET_NR_unlink              10
+#define TARGET_NR_execve              11
+#define TARGET_NR_chdir               12
+#define TARGET_NR_mknod               14
+#define TARGET_NR_chmod               15
+#define TARGET_NR_lseek               19
+#define TARGET_NR_getpid              20
+#define TARGET_NR_mount               21
+#define TARGET_NR_umount              22
+#define TARGET_NR_ptrace              26
+#define TARGET_NR_alarm               27
+#define TARGET_NR_pause               29
+#define TARGET_NR_utime               30
+#define TARGET_NR_access              33
+#define TARGET_NR_nice                34
+#define TARGET_NR_sync                36
+#define TARGET_NR_kill                37
+#define TARGET_NR_rename              38
+#define TARGET_NR_mkdir               39
+#define TARGET_NR_rmdir               40
+#define TARGET_NR_dup                 41
+#define TARGET_NR_pipe                42
+#define TARGET_NR_times               43
+#define TARGET_NR_brk                 45
+#define TARGET_NR_signal              48
+#define TARGET_NR_acct                51
+#define TARGET_NR_umount2             52
+#define TARGET_NR_ioctl               54
+#define TARGET_NR_fcntl               55
+#define TARGET_NR_setpgid             57
+#define TARGET_NR_umask               60
+#define TARGET_NR_chroot              61
+#define TARGET_NR_ustat               62
+#define TARGET_NR_dup2                63
+#define TARGET_NR_getppid             64
+#define TARGET_NR_getpgrp             65
+#define TARGET_NR_setsid              66
+#define TARGET_NR_sigaction           67
+#define TARGET_NR_sigsuspend          72
+#define TARGET_NR_sigpending          73
+#define TARGET_NR_sethostname         74
+#define TARGET_NR_setrlimit           75
+#define TARGET_NR_getrusage           77
+#define TARGET_NR_gettimeofday        78
+#define TARGET_NR_settimeofday        79
+#define TARGET_NR_symlink             83
+#define TARGET_NR_readlink            85
+#define TARGET_NR_uselib              86
+#define TARGET_NR_swapon              87
+#define TARGET_NR_reboot              88
+#define TARGET_NR_readdir             89
+#define TARGET_NR_mmap                90
+#define TARGET_NR_munmap              91
+#define TARGET_NR_truncate            92
+#define TARGET_NR_ftruncate           93
+#define TARGET_NR_fchmod              94
+#define TARGET_NR_getpriority         96
+#define TARGET_NR_setpriority         97
+#define TARGET_NR_statfs              99
+#define TARGET_NR_fstatfs            100
+#define TARGET_NR_socketcall         102
+#define TARGET_NR_syslog             103
+#define TARGET_NR_setitimer          104
+#define TARGET_NR_getitimer          105
+#define TARGET_NR_stat               106
+#define TARGET_NR_lstat              107
+#define TARGET_NR_fstat              108
+#define TARGET_NR_lookup_dcookie     110
+#define TARGET_NR_vhangup            111
+#define TARGET_NR_idle               112
+#define TARGET_NR_wait4              114
+#define TARGET_NR_swapoff            115
+#define TARGET_NR_sysinfo            116
+#define TARGET_NR_ipc                117
+#define TARGET_NR_fsync              118
+#define TARGET_NR_sigreturn          119
+#define TARGET_NR_clone              120
+#define TARGET_NR_setdomainname      121
+#define TARGET_NR_uname              122
+#define TARGET_NR_adjtimex           124
+#define TARGET_NR_mprotect           125
+#define TARGET_NR_sigprocmask        126
+#define TARGET_NR_create_module      127
+#define TARGET_NR_init_module        128
+#define TARGET_NR_delete_module      129
+#define TARGET_NR_get_kernel_syms    130
+#define TARGET_NR_quotactl           131
+#define TARGET_NR_getpgid            132
+#define TARGET_NR_fchdir             133
+#define TARGET_NR_bdflush            134
+#define TARGET_NR_sysfs              135
+#define TARGET_NR_personality        136
+#define TARGET_NR_afs_syscall        137 /* Syscall for Andrew File System */
+#define TARGET_NR_getdents           141
+#define TARGET_NR_flock              143
+#define TARGET_NR_msync              144
+#define TARGET_NR_readv              145
+#define TARGET_NR_writev             146
+#define TARGET_NR_getsid             147
+#define TARGET_NR_fdatasync          148
+#define TARGET_NR__sysctl            149
+#define TARGET_NR_mlock              150
+#define TARGET_NR_munlock            151
+#define TARGET_NR_mlockall           152
+#define TARGET_NR_munlockall         153
+#define TARGET_NR_sched_setparam             154
+#define TARGET_NR_sched_getparam             155
+#define TARGET_NR_sched_setscheduler         156
+#define TARGET_NR_sched_getscheduler         157
+#define TARGET_NR_sched_yield                158
+#define TARGET_NR_sched_get_priority_max     159
+#define TARGET_NR_sched_get_priority_min     160
+#define TARGET_NR_sched_rr_get_interval      161
+#define TARGET_NR_nanosleep          162
+#define TARGET_NR_mremap             163
+#define TARGET_NR_query_module       167
+#define TARGET_NR_poll               168
+#define TARGET_NR_nfsservctl         169
+#define TARGET_NR_prctl              172
+#define TARGET_NR_rt_sigreturn       173
+#define TARGET_NR_rt_sigaction       174
+#define TARGET_NR_rt_sigprocmask     175
+#define TARGET_NR_rt_sigpending      176
+#define TARGET_NR_rt_sigtimedwait    177
+#define TARGET_NR_rt_sigqueueinfo    178
+#define TARGET_NR_rt_sigsuspend      179
+#define TARGET_NR_pread64            180
+#define TARGET_NR_pwrite64           181
+#define TARGET_NR_getcwd             183
+#define TARGET_NR_capget             184
+#define TARGET_NR_capset             185
+#define TARGET_NR_sigaltstack        186
+#define TARGET_NR_sendfile           187
+#define TARGET_NR_getpmsg		188
+#define TARGET_NR_putpmsg		189
+#define TARGET_NR_vfork		190
+#define TARGET_NR_pivot_root         217
+#define TARGET_NR_mincore            218
+#define TARGET_NR_madvise            219
+#define TARGET_NR_getdents64		220
+#define TARGET_NR_readahead		222
+#define TARGET_NR_setxattr		224
+#define TARGET_NR_lsetxattr		225
+#define TARGET_NR_fsetxattr		226
+#define TARGET_NR_getxattr		227
+#define TARGET_NR_lgetxattr		228
+#define TARGET_NR_fgetxattr		229
+#define TARGET_NR_listxattr		230
+#define TARGET_NR_llistxattr		231
+#define TARGET_NR_flistxattr		232
+#define TARGET_NR_removexattr	233
+#define TARGET_NR_lremovexattr	234
+#define TARGET_NR_fremovexattr	235
+#define TARGET_NR_gettid		236
+#define TARGET_NR_tkill		237
+#define TARGET_NR_futex		238
+#define TARGET_NR_sched_setaffinity	239
+#define TARGET_NR_sched_getaffinity	240
+#define TARGET_NR_tgkill		241
+/* Number 242 is reserved for tux */
+#define TARGET_NR_io_setup		243
+#define TARGET_NR_io_destroy		244
+#define TARGET_NR_io_getevents	245
+#define TARGET_NR_io_submit		246
+#define TARGET_NR_io_cancel		247
+#define TARGET_NR_exit_group		248
+#define TARGET_NR_epoll_create	249
+#define TARGET_NR_epoll_ctl		250
+#define TARGET_NR_epoll_wait		251
+#define TARGET_NR_set_tid_address	252
+#define TARGET_NR_fadvise64		253
+#define TARGET_NR_timer_create	254
+#define TARGET_NR_timer_settime	(TARGET_NR_timer_create+1)
+#define TARGET_NR_timer_gettime	(TARGET_NR_timer_create+2)
+#define TARGET_NR_timer_getoverrun	(TARGET_NR_timer_create+3)
+#define TARGET_NR_timer_delete	(TARGET_NR_timer_create+4)
+#define TARGET_NR_clock_settime	(TARGET_NR_timer_create+5)
+#define TARGET_NR_clock_gettime	(TARGET_NR_timer_create+6)
+#define TARGET_NR_clock_getres	(TARGET_NR_timer_create+7)
+#define TARGET_NR_clock_nanosleep	(TARGET_NR_timer_create+8)
+/* Number 263 is reserved for vserver */
+#define TARGET_NR_statfs64		265
+#define TARGET_NR_fstatfs64		266
+#define TARGET_NR_remap_file_pages	267
+/* Number 268 is reserved for new sys_mbind */
+/* Number 269 is reserved for new sys_get_mempolicy */
+/* Number 270 is reserved for new sys_set_mempolicy */
+#define TARGET_NR_mq_open		271
+#define TARGET_NR_mq_unlink		272
+#define TARGET_NR_mq_timedsend	273
+#define TARGET_NR_mq_timedreceive	274
+#define TARGET_NR_mq_notify		275
+#define TARGET_NR_mq_getsetattr	276
+#define TARGET_NR_kexec_load		277
+#define TARGET_NR_add_key		278
+#define TARGET_NR_request_key	279
+#define TARGET_NR_keyctl		280
+#define TARGET_NR_waitid		281
+#define TARGET_NR_ioprio_set		282
+#define TARGET_NR_ioprio_get		283
+#define TARGET_NR_inotify_init	284
+#define TARGET_NR_inotify_add_watch	285
+#define TARGET_NR_inotify_rm_watch	286
+/* Number 287 is reserved for new sys_migrate_pages */
+#define TARGET_NR_openat		288
+#define TARGET_NR_mkdirat		289
+#define TARGET_NR_mknodat		290
+#define TARGET_NR_fchownat		291
+#define TARGET_NR_futimesat		292
+#define TARGET_NR_unlinkat		294
+#define TARGET_NR_renameat		295
+#define TARGET_NR_linkat		296
+#define TARGET_NR_symlinkat		297
+#define TARGET_NR_readlinkat		298
+#define TARGET_NR_fchmodat		299
+#define TARGET_NR_faccessat		300
+#define TARGET_NR_pselect6		301
+#define TARGET_NR_ppoll		302
+#define TARGET_NR_unshare		303
+#define TARGET_NR_set_robust_list	304
+#define TARGET_NR_get_robust_list	305
+#define TARGET_NR_splice		306
+#define TARGET_NR_sync_file_range	307
+#define TARGET_NR_tee		308
+#define TARGET_NR_vmsplice		309
+/* Number 310 is reserved for new sys_move_pages */
+#define TARGET_NR_getcpu		311
+#define TARGET_NR_epoll_pwait	312
+#define TARGET_NR_utimes		313
+#define TARGET_NR_fallocate		314
+#define TARGET_NR_utimensat		315
+#define TARGET_NR_signalfd		316
+#define TARGET_NR_timerfd		317
+#define TARGET_NR_eventfd		318
+#define TARGET_NR_timerfd_create	319
+#define TARGET_NR_timerfd_settime	320
+#define TARGET_NR_timerfd_gettime	321
+#define TARGET_NR_signalfd4		322
+#define TARGET_NR_eventfd2		323
+#define TARGET_NR_inotify_init1	324
+#define TARGET_NR_pipe2		325
+#define TARGET_NR_dup3		326
+#define TARGET_NR_epoll_create1	327
+#define NR_syscalls 328
+
+/* 
+ * There are some system calls that are not present on 64 bit, some
+ * have a different name although they do the same (e.g. TARGET_NR_chown32
+ * is TARGET_NR_chown on 64 bit).
+ */
+#ifndef TARGET_S390X
+
+#define TARGET_NR_time		 13
+#define TARGET_NR_lchown		 16
+#define TARGET_NR_setuid		 23
+#define TARGET_NR_getuid		 24
+#define TARGET_NR_stime		 25
+#define TARGET_NR_setgid		 46
+#define TARGET_NR_getgid		 47
+#define TARGET_NR_geteuid		 49
+#define TARGET_NR_getegid		 50
+#define TARGET_NR_setreuid		 70
+#define TARGET_NR_setregid		 71
+#define TARGET_NR_getrlimit		 76
+#define TARGET_NR_getgroups		 80
+#define TARGET_NR_setgroups		 81
+#define TARGET_NR_fchown		 95
+#define TARGET_NR_ioperm		101
+#define TARGET_NR_setfsuid		138
+#define TARGET_NR_setfsgid		139
+#define TARGET_NR__llseek		140
+#define TARGET_NR__newselect 	142
+#define TARGET_NR_setresuid		164
+#define TARGET_NR_getresuid		165
+#define TARGET_NR_setresgid		170
+#define TARGET_NR_getresgid		171
+#define TARGET_NR_chown		182
+#define TARGET_NR_ugetrlimit		191	/* SuS compliant getrlimit */
+#define TARGET_NR_mmap2		192
+#define TARGET_NR_truncate64		193
+#define TARGET_NR_ftruncate64	194
+#define TARGET_NR_stat64		195
+#define TARGET_NR_lstat64		196
+#define TARGET_NR_fstat64		197
+#define TARGET_NR_lchown32		198
+#define TARGET_NR_getuid32		199
+#define TARGET_NR_getgid32		200
+#define TARGET_NR_geteuid32		201
+#define TARGET_NR_getegid32		202
+#define TARGET_NR_setreuid32		203
+#define TARGET_NR_setregid32		204
+#define TARGET_NR_getgroups32	205
+#define TARGET_NR_setgroups32	206
+#define TARGET_NR_fchown32		207
+#define TARGET_NR_setresuid32	208
+#define TARGET_NR_getresuid32	209
+#define TARGET_NR_setresgid32	210
+#define TARGET_NR_getresgid32	211
+#define TARGET_NR_chown32		212
+#define TARGET_NR_setuid32		213
+#define TARGET_NR_setgid32		214
+#define TARGET_NR_setfsuid32		215
+#define TARGET_NR_setfsgid32		216
+#define TARGET_NR_fcntl64		221
+#define TARGET_NR_sendfile64		223
+#define TARGET_NR_fadvise64_64	264
+#define TARGET_NR_fstatat64		293
+
+#else
+
+#define TARGET_NR_select		142
+#define TARGET_NR_getrlimit		191	/* SuS compliant getrlimit */
+#define TARGET_NR_lchown  		198
+#define TARGET_NR_getuid  		199
+#define TARGET_NR_getgid  		200
+#define TARGET_NR_geteuid  		201
+#define TARGET_NR_getegid  		202
+#define TARGET_NR_setreuid  		203
+#define TARGET_NR_setregid  		204
+#define TARGET_NR_getgroups  	205
+#define TARGET_NR_setgroups  	206
+#define TARGET_NR_fchown  		207
+#define TARGET_NR_setresuid  	208
+#define TARGET_NR_getresuid  	209
+#define TARGET_NR_setresgid  	210
+#define TARGET_NR_getresgid  	211
+#define TARGET_NR_chown  		212
+#define TARGET_NR_setuid  		213
+#define TARGET_NR_setgid  		214
+#define TARGET_NR_setfsuid  		215
+#define TARGET_NR_setfsgid  		216
+#define TARGET_NR_newfstatat		293
+
+#endif
+
diff --git a/linux-user/s390x/target_signal.h b/linux-user/s390x/target_signal.h
new file mode 100644
index 0000000..b4816b0
--- /dev/null
+++ b/linux-user/s390x/target_signal.h
@@ -0,0 +1,26 @@ 
+#ifndef TARGET_SIGNAL_H
+#define TARGET_SIGNAL_H
+
+#include "cpu.h"
+
+typedef struct target_sigaltstack {
+    abi_ulong ss_sp;
+    int ss_flags;
+    abi_ulong ss_size;
+} target_stack_t;
+
+/*
+ * sigaltstack controls
+ */
+#define TARGET_SS_ONSTACK      1
+#define TARGET_SS_DISABLE      2
+
+#define TARGET_MINSIGSTKSZ     2048
+#define TARGET_SIGSTKSZ        8192
+
+static inline abi_ulong get_sp_from_cpustate(CPUS390XState *state)
+{
+   return state->regs[15];
+}
+
+#endif /* TARGET_SIGNAL_H */
diff --git a/linux-user/s390x/termbits.h b/linux-user/s390x/termbits.h
new file mode 100644
index 0000000..2a78a05
--- /dev/null
+++ b/linux-user/s390x/termbits.h
@@ -0,0 +1,283 @@ 
+/*
+ *  include/asm-s390/termbits.h
+ *
+ *  S390 version
+ *
+ *  Derived from "include/asm-i386/termbits.h"
+ */
+
+#define TARGET_NCCS 19
+struct target_termios {
+    unsigned int c_iflag;		/* input mode flags */
+    unsigned int c_oflag;		/* output mode flags */
+    unsigned int c_cflag;		/* control mode flags */
+    unsigned int c_lflag;		/* local mode flags */
+    unsigned char c_line;			/* line discipline */
+    unsigned char c_cc[TARGET_NCCS];		/* control characters */
+};
+
+struct target_termios2 {
+    unsigned int c_iflag;		/* input mode flags */
+    unsigned int c_oflag;		/* output mode flags */
+    unsigned int c_cflag;		/* control mode flags */
+    unsigned int c_lflag;		/* local mode flags */
+    unsigned char c_line;			/* line discipline */
+    unsigned char c_cc[TARGET_NCCS];		/* control characters */
+    unsigned int c_ispeed;		/* input speed */
+    unsigned int c_ospeed;		/* output speed */
+};
+
+struct target_ktermios {
+    unsigned int c_iflag;		/* input mode flags */
+    unsigned int c_oflag;		/* output mode flags */
+    unsigned int c_cflag;		/* control mode flags */
+    unsigned int c_lflag;		/* local mode flags */
+    unsigned char c_line;			/* line discipline */
+    unsigned char c_cc[TARGET_NCCS];		/* control characters */
+    unsigned int c_ispeed;		/* input speed */
+    unsigned int c_ospeed;		/* output speed */
+};
+
+/* c_cc characters */
+#define TARGET_VINTR 0
+#define TARGET_VQUIT 1
+#define TARGET_VERASE 2
+#define TARGET_VKILL 3
+#define TARGET_VEOF 4
+#define TARGET_VTIME 5
+#define TARGET_VMIN 6
+#define TARGET_VSWTC 7
+#define TARGET_VSTART 8
+#define TARGET_VSTOP 9
+#define TARGET_VSUSP 10
+#define TARGET_VEOL 11
+#define TARGET_VREPRINT 12
+#define TARGET_VDISCARD 13
+#define TARGET_VWERASE 14
+#define TARGET_VLNEXT 15
+#define TARGET_VEOL2 16
+
+/* c_iflag bits */
+#define TARGET_IGNBRK	0000001
+#define TARGET_BRKINT	0000002
+#define TARGET_IGNPAR	0000004
+#define TARGET_PARMRK	0000010
+#define TARGET_INPCK	0000020
+#define TARGET_ISTRIP	0000040
+#define TARGET_INLCR	0000100
+#define TARGET_IGNCR	0000200
+#define TARGET_ICRNL	0000400
+#define TARGET_IUCLC	0001000
+#define TARGET_IXON	0002000
+#define TARGET_IXANY	0004000
+#define TARGET_IXOFF	0010000
+#define TARGET_IMAXBEL	0020000
+#define TARGET_IUTF8	0040000
+
+/* c_oflag bits */
+#define TARGET_OPOST	0000001
+#define TARGET_OLCUC	0000002
+#define TARGET_ONLCR	0000004
+#define TARGET_OCRNL	0000010
+#define TARGET_ONOCR	0000020
+#define TARGET_ONLRET	0000040
+#define TARGET_OFILL	0000100
+#define TARGET_OFDEL	0000200
+#define TARGET_NLDLY	0000400
+#define TARGET_NL0	0000000
+#define TARGET_NL1	0000400
+#define TARGET_CRDLY	0003000
+#define TARGET_CR0	0000000
+#define TARGET_CR1	0001000
+#define TARGET_CR2	0002000
+#define TARGET_CR3	0003000
+#define TARGET_TABDLY	0014000
+#define TARGET_TAB0	0000000
+#define TARGET_TAB1	0004000
+#define TARGET_TAB2	0010000
+#define TARGET_TAB3	0014000
+#define TARGET_XTABS	0014000
+#define TARGET_BSDLY	0020000
+#define TARGET_BS0	0000000
+#define TARGET_BS1	0020000
+#define TARGET_VTDLY	0040000
+#define TARGET_VT0	0000000
+#define TARGET_VT1	0040000
+#define TARGET_FFDLY	0100000
+#define TARGET_FF0	0000000
+#define TARGET_FF1	0100000
+
+/* c_cflag bit meaning */
+#define TARGET_CBAUD	0010017
+#define TARGET_B0	0000000		/* hang up */
+#define TARGET_B50	0000001
+#define TARGET_B75	0000002
+#define TARGET_B110	0000003
+#define TARGET_B134	0000004
+#define TARGET_B150	0000005
+#define TARGET_B200	0000006
+#define TARGET_B300	0000007
+#define TARGET_B600	0000010
+#define TARGET_B1200	0000011
+#define TARGET_B1800	0000012
+#define TARGET_B2400	0000013
+#define TARGET_B4800	0000014
+#define TARGET_B9600	0000015
+#define TARGET_B19200	0000016
+#define TARGET_B38400	0000017
+#define TARGET_EXTA B19200
+#define TARGET_EXTB B38400
+#define TARGET_CSIZE	0000060
+#define TARGET_CS5	0000000
+#define TARGET_CS6	0000020
+#define TARGET_CS7	0000040
+#define TARGET_CS8	0000060
+#define TARGET_CSTOPB	0000100
+#define TARGET_CREAD	0000200
+#define TARGET_PARENB	0000400
+#define TARGET_PARODD	0001000
+#define TARGET_HUPCL	0002000
+#define TARGET_CLOCAL	0004000
+#define TARGET_CBAUDEX 0010000
+#define TARGET_BOTHER  0010000
+#define TARGET_B57600  0010001
+#define TARGET_B115200 0010002
+#define TARGET_B230400 0010003
+#define TARGET_B460800 0010004
+#define TARGET_B500000 0010005
+#define TARGET_B576000 0010006
+#define TARGET_B921600 0010007
+#define TARGET_B1000000 0010010
+#define TARGET_B1152000 0010011
+#define TARGET_B1500000 0010012
+#define TARGET_B2000000 0010013
+#define TARGET_B2500000 0010014
+#define TARGET_B3000000 0010015
+#define TARGET_B3500000 0010016
+#define TARGET_B4000000 0010017
+#define TARGET_CIBAUD	  002003600000	/* input baud rate */
+#define TARGET_CMSPAR	  010000000000		/* mark or space (stick) parity */
+#define TARGET_CRTSCTS	  020000000000		/* flow control */
+
+#define TARGET_IBSHIFT	  16		/* Shift from CBAUD to CIBAUD */
+
+/* c_lflag bits */
+#define TARGET_ISIG	0000001
+#define TARGET_ICANON	0000002
+#define TARGET_XCASE	0000004
+#define TARGET_ECHO	0000010
+#define TARGET_ECHOE	0000020
+#define TARGET_ECHOK	0000040
+#define TARGET_ECHONL	0000100
+#define TARGET_NOFLSH	0000200
+#define TARGET_TOSTOP	0000400
+#define TARGET_ECHOCTL	0001000
+#define TARGET_ECHOPRT	0002000
+#define TARGET_ECHOKE	0004000
+#define TARGET_FLUSHO	0010000
+#define TARGET_PENDIN	0040000
+#define TARGET_IEXTEN	0100000
+
+/* tcflow() and TCXONC use these */
+#define	TARGET_TCOOFF		0
+#define	TARGET_TCOON		1
+#define	TARGET_TCIOFF		2
+#define	TARGET_TCION		3
+
+/* tcflush() and TCFLSH use these */
+#define	TARGET_TCIFLUSH	0
+#define	TARGET_TCOFLUSH	1
+#define	TARGET_TCIOFLUSH	2
+
+/* tcsetattr uses these */
+#define	TARGET_TCSANOW		0
+#define	TARGET_TCSADRAIN	1
+#define	TARGET_TCSAFLUSH	2
+
+/*
+ *  include/asm-s390/ioctls.h
+ *
+ *  S390 version
+ *
+ *  Derived from "include/asm-i386/ioctls.h"
+ */
+
+/* 0x54 is just a magic number to make these relatively unique ('T') */
+
+#define TARGET_TCGETS		0x5401
+#define TARGET_TCSETS		0x5402
+#define TARGET_TCSETSW		0x5403
+#define TARGET_TCSETSF		0x5404
+#define TARGET_TCGETA		0x5405
+#define TARGET_TCSETA		0x5406
+#define TARGET_TCSETAW		0x5407
+#define TARGET_TCSETAF		0x5408
+#define TARGET_TCSBRK		0x5409
+#define TARGET_TCXONC		0x540A
+#define TARGET_TCFLSH		0x540B
+#define TARGET_TIOCEXCL	0x540C
+#define TARGET_TIOCNXCL	0x540D
+#define TARGET_TIOCSCTTY	0x540E
+#define TARGET_TIOCGPGRP	0x540F
+#define TARGET_TIOCSPGRP	0x5410
+#define TARGET_TIOCOUTQ	0x5411
+#define TARGET_TIOCSTI		0x5412
+#define TARGET_TIOCGWINSZ	0x5413
+#define TARGET_TIOCSWINSZ	0x5414
+#define TARGET_TIOCMGET	0x5415
+#define TARGET_TIOCMBIS	0x5416
+#define TARGET_TIOCMBIC	0x5417
+#define TARGET_TIOCMSET	0x5418
+#define TARGET_TIOCGSOFTCAR	0x5419
+#define TARGET_TIOCSSOFTCAR	0x541A
+#define TARGET_FIONREAD	0x541B
+#define TARGET_TIOCINQ		FIONREAD
+#define TARGET_TIOCLINUX	0x541C
+#define TARGET_TIOCCONS	0x541D
+#define TARGET_TIOCGSERIAL	0x541E
+#define TARGET_TIOCSSERIAL	0x541F
+#define TARGET_TIOCPKT		0x5420
+#define TARGET_FIONBIO		0x5421
+#define TARGET_TIOCNOTTY	0x5422
+#define TARGET_TIOCSETD	0x5423
+#define TARGET_TIOCGETD	0x5424
+#define TARGET_TCSBRKP		0x5425	/* Needed for POSIX tcsendbreak() */
+#define TARGET_TIOCSBRK	0x5427  /* BSD compatibility */
+#define TARGET_TIOCCBRK	0x5428  /* BSD compatibility */
+#define TARGET_TIOCGSID	0x5429  /* Return the session ID of FD */
+#define TARGET_TCGETS2		_IOR('T',0x2A, struct termios2)
+#define TARGET_TCSETS2		_IOW('T',0x2B, struct termios2)
+#define TARGET_TCSETSW2	_IOW('T',0x2C, struct termios2)
+#define TARGET_TCSETSF2	_IOW('T',0x2D, struct termios2)
+#define TARGET_TIOCGPTN	_IOR('T',0x30, unsigned int) /* Get Pty Number (of pty-mux device) */
+#define TARGET_TIOCSPTLCK	_IOW('T',0x31, int)  /* Lock/unlock Pty */
+#define TARGET_TIOCGDEV	_IOR('T',0x32, unsigned int) /* Get real dev no below /dev/console */
+
+#define TARGET_FIONCLEX	0x5450  /* these numbers need to be adjusted. */
+#define TARGET_FIOCLEX		0x5451
+#define TARGET_FIOASYNC	0x5452
+#define TARGET_TIOCSERCONFIG	0x5453
+#define TARGET_TIOCSERGWILD	0x5454
+#define TARGET_TIOCSERSWILD	0x5455
+#define TARGET_TIOCGLCKTRMIOS	0x5456
+#define TARGET_TIOCSLCKTRMIOS	0x5457
+#define TARGET_TIOCSERGSTRUCT	0x5458 /* For debugging only */
+#define TARGET_TIOCSERGETLSR   0x5459 /* Get line status register */
+#define TARGET_TIOCSERGETMULTI 0x545A /* Get multiport config  */
+#define TARGET_TIOCSERSETMULTI 0x545B /* Set multiport config */
+
+#define TARGET_TIOCMIWAIT	0x545C	/* wait for a change on serial input line(s) */
+#define TARGET_TIOCGICOUNT	0x545D	/* read serial port inline interrupt counts */
+#define TARGET_FIOQSIZE	0x545E
+
+/* Used for packet mode */
+#define TARGET_TIOCPKT_DATA		 0
+#define TARGET_TIOCPKT_FLUSHREAD	 1
+#define TARGET_TIOCPKT_FLUSHWRITE	 2
+#define TARGET_TIOCPKT_STOP		 4
+#define TARGET_TIOCPKT_START		 8
+#define TARGET_TIOCPKT_NOSTOP		16
+#define TARGET_TIOCPKT_DOSTOP		32
+
+#define TARGET_TIOCSER_TEMT    0x01	/* Transmitter physically empty */
+
diff --git a/linux-user/signal.c b/linux-user/signal.c
index 2df17aa..fe74ba5 100644
--- a/linux-user/signal.c
+++ b/linux-user/signal.c
@@ -3432,6 +3432,320 @@  long do_rt_sigreturn(CPUState *env)
     return -TARGET_ENOSYS;
 }
 
+#elif defined(TARGET_S390X)
+
+#define __NUM_GPRS 16
+#define __NUM_FPRS 16
+#define __NUM_ACRS 16
+
+#define S390_SYSCALL_SIZE   2
+#define __SIGNAL_FRAMESIZE      160 /* FIXME: 31-bit mode -> 96 */
+
+#define _SIGCONTEXT_NSIG        64
+#define _SIGCONTEXT_NSIG_BPW    64 /* FIXME: 31-bit mode -> 32 */
+#define _SIGCONTEXT_NSIG_WORDS  (_SIGCONTEXT_NSIG / _SIGCONTEXT_NSIG_BPW)
+#define _SIGMASK_COPY_SIZE    (sizeof(unsigned long)*_SIGCONTEXT_NSIG_WORDS)
+#define PSW_ADDR_AMODE            0x0000000000000000UL /* 0x80000000UL for 31-bit */
+#define S390_SYSCALL_OPCODE ((uint16_t)0x0a00)
+
+typedef struct
+{
+    target_psw_t psw;
+    target_ulong gprs[__NUM_GPRS];
+    unsigned int  acrs[__NUM_ACRS];
+} target_s390_regs_common;
+
+typedef struct
+{
+    unsigned int fpc;
+    double   fprs[__NUM_FPRS];
+} target_s390_fp_regs;
+
+typedef struct
+{
+    target_s390_regs_common regs;
+    target_s390_fp_regs     fpregs;
+} target_sigregs;
+
+struct target_sigcontext
+{
+    target_ulong   oldmask[_SIGCONTEXT_NSIG_WORDS];
+    target_sigregs        *sregs;
+};
+
+typedef struct
+{
+    uint8_t callee_used_stack[__SIGNAL_FRAMESIZE];
+    struct target_sigcontext sc;
+    target_sigregs sregs;
+    int signo;
+    uint8_t retcode[S390_SYSCALL_SIZE];
+} sigframe;
+
+struct target_ucontext {
+    target_ulong      uc_flags;
+    struct target_ucontext  *uc_link;
+    target_stack_t           uc_stack;
+    target_sigregs          uc_mcontext;
+    target_sigset_t   uc_sigmask;   /* mask last for extensibility */
+};
+                                        
+typedef struct
+{
+    uint8_t callee_used_stack[__SIGNAL_FRAMESIZE];
+    uint8_t retcode[S390_SYSCALL_SIZE];
+    struct target_siginfo info;
+    struct target_ucontext uc;
+} rt_sigframe;
+
+static inline abi_ulong
+get_sigframe(struct target_sigaction *ka, CPUState *env, size_t frame_size)
+{
+    abi_ulong sp;
+
+    /* Default to using normal stack */
+    sp = env->regs[15];
+
+    /* This is the X/Open sanctioned signal stack switching.  */
+    if (ka->sa_flags & TARGET_SA_ONSTACK) {
+        if (! sas_ss_flags(sp))
+            sp = target_sigaltstack_used.ss_sp + target_sigaltstack_used.ss_size;
+    }
+
+    /* This is the legacy signal stack switching. */
+    else if (/* FIXME !user_mode(regs) */ 0 &&
+             !(ka->sa_flags & TARGET_SA_RESTORER) &&
+             ka->sa_restorer) {
+        sp = (abi_ulong) ka->sa_restorer;
+    }
+
+    return (sp - frame_size) & -8ul;
+}
+
+static void save_sigregs(CPUState *env, target_sigregs *sregs)
+{
+    int i;
+    //save_access_regs(current->thread.acrs); FIXME
+
+    /* Copy a 'clean' PSW mask to the user to avoid leaking
+       information about whether PER is currently on.  */
+    __put_user(env->psw.mask, &sregs->regs.psw.mask);
+    __put_user(env->psw.addr, &sregs->regs.psw.addr);
+    for (i = 0; i < 16; i++)
+        __put_user(env->regs[i], &sregs->regs.gprs[i]);
+    for (i = 0; i < 16; i++)
+        __put_user(env->aregs[i], &sregs->regs.acrs[i]);
+    /*
+     * We have to store the fp registers to current->thread.fp_regs
+     * to merge them with the emulated registers.
+     */
+    //save_fp_regs(&current->thread.fp_regs); FIXME
+    for (i = 0; i < 16; i++)
+        __put_user(env->fregs[i].ll, &sregs->fpregs.fprs[i]);
+}
+
+static void setup_frame(int sig, struct target_sigaction *ka,
+			target_sigset_t *set, CPUState *env)
+{
+    sigframe *frame;
+    abi_ulong frame_addr;
+
+    frame_addr = get_sigframe(ka, env, sizeof *frame);
+    qemu_log("%s: frame_addr 0x%lx\n", __FUNCTION__, frame_addr);
+    if (!lock_user_struct(VERIFY_WRITE, frame, frame_addr, 0))
+            goto give_sigsegv;
+
+    qemu_log("%s: 1\n", __FUNCTION__);
+    if (__put_user(set->sig[0], &frame->sc.oldmask[0]))
+              goto give_sigsegv;
+
+    save_sigregs(env, &frame->sregs);
+
+    __put_user((abi_ulong)&frame->sregs, (abi_ulong *)&frame->sc.sregs);
+
+    /* Set up to return from userspace.  If provided, use a stub
+       already in userspace.  */
+    if (ka->sa_flags & TARGET_SA_RESTORER) {
+            env->regs[14] = (unsigned long)
+                    ka->sa_restorer | PSW_ADDR_AMODE;
+    } else {
+            env->regs[14] = (unsigned long)
+                    frame->retcode | PSW_ADDR_AMODE;
+            if (__put_user(S390_SYSCALL_OPCODE | TARGET_NR_sigreturn,
+                           (uint16_t *)(frame->retcode)))
+                    goto give_sigsegv;
+    }
+
+    /* Set up backchain. */
+    if (__put_user(env->regs[15], (abi_ulong *) frame))
+            goto give_sigsegv;
+
+    /* Set up registers for signal handler */
+    env->regs[15] = (target_ulong) frame;
+    env->psw.addr = (target_ulong) ka->_sa_handler | PSW_ADDR_AMODE;
+
+    env->regs[2] = sig; //map_signal(sig);
+    env->regs[3] = (target_ulong) &frame->sc;
+
+    /* We forgot to include these in the sigcontext.
+       To avoid breaking binary compatibility, they are passed as args. */
+    env->regs[4] = 0; // FIXME: no clue... current->thread.trap_no;
+    env->regs[5] = 0; // FIXME: no clue... current->thread.prot_addr;
+
+    /* Place signal number on stack to allow backtrace from handler.  */
+    if (__put_user(env->regs[2], (int *) &frame->signo))
+            goto give_sigsegv;
+    unlock_user_struct(frame, frame_addr, 1);
+    return;
+
+give_sigsegv:
+    qemu_log("%s: give_sigsegv\n", __FUNCTION__);
+    unlock_user_struct(frame, frame_addr, 1);
+    force_sig(TARGET_SIGSEGV);
+}
+
+static void setup_rt_frame(int sig, struct target_sigaction *ka,
+                        target_siginfo_t *info,
+			target_sigset_t *set, CPUState *env)
+{
+    int i;
+    rt_sigframe *frame;
+    abi_ulong frame_addr;
+
+    frame_addr = get_sigframe(ka, env, sizeof *frame);
+    qemu_log("%s: frame_addr 0x%lx\n", __FUNCTION__, frame_addr);
+    if (!lock_user_struct(VERIFY_WRITE, frame, frame_addr, 0))
+            goto give_sigsegv;
+
+    qemu_log("%s: 1\n", __FUNCTION__);
+    if (copy_siginfo_to_user(&frame->info, info))
+              goto give_sigsegv;
+
+    /* Create the ucontext.  */
+    __put_user(0, &frame->uc.uc_flags);
+    __put_user((abi_ulong)NULL, (abi_ulong*)&frame->uc.uc_link);
+    __put_user(target_sigaltstack_used.ss_sp, &frame->uc.uc_stack.ss_sp);
+    __put_user(sas_ss_flags(get_sp_from_cpustate(env)),
+                      &frame->uc.uc_stack.ss_flags);
+    __put_user(target_sigaltstack_used.ss_size, &frame->uc.uc_stack.ss_size);
+    save_sigregs(env, &frame->uc.uc_mcontext);
+    for(i = 0; i < TARGET_NSIG_WORDS; i++) {
+        __put_user((abi_ulong)set->sig[i], (abi_ulong*)&frame->uc.uc_sigmask.sig[i]);
+    }
+
+    /* Set up to return from userspace.  If provided, use a stub
+       already in userspace.  */
+    if (ka->sa_flags & TARGET_SA_RESTORER) {
+            env->regs[14] = (unsigned long)
+                    ka->sa_restorer | PSW_ADDR_AMODE;
+    } else {
+            env->regs[14] = (unsigned long)
+                    frame->retcode | PSW_ADDR_AMODE;
+            if (__put_user(S390_SYSCALL_OPCODE | TARGET_NR_rt_sigreturn,
+                           (uint16_t *)(frame->retcode)))
+                    goto give_sigsegv;
+    }
+
+    /* Set up backchain. */
+    if (__put_user(env->regs[15], (abi_ulong *) frame))
+            goto give_sigsegv;
+
+    /* Set up registers for signal handler */
+    env->regs[15] = (target_ulong) frame;
+    env->psw.addr = (target_ulong) ka->_sa_handler | PSW_ADDR_AMODE;
+
+    env->regs[2] = sig; //map_signal(sig);
+    env->regs[3] = (target_ulong) &frame->info;
+    env->regs[4] = (target_ulong) &frame->uc;
+    return;
+
+give_sigsegv:
+    qemu_log("%s: give_sigsegv\n", __FUNCTION__);
+    unlock_user_struct(frame, frame_addr, 1);
+    force_sig(TARGET_SIGSEGV);
+}
+
+static int
+restore_sigregs(CPUState *env, target_sigregs *sc)
+{
+    int err = 0;
+    int i;
+
+    for (i = 0; i < 16; i++) {
+        err |= __get_user(env->regs[i], &sc->regs.gprs[i]);
+    }
+
+    err |= __get_user(env->psw.mask, &sc->regs.psw.mask);
+    qemu_log("%s: sc->regs.psw.addr 0x%lx env->psw.addr 0x%lx\n", __FUNCTION__, sc->regs.psw.addr, env->psw.addr);
+    err |= __get_user(env->psw.addr, &sc->regs.psw.addr);
+    /* FIXME: 31-bit -> | PSW_ADDR_AMODE */
+    
+    for (i = 0; i < 16; i++) {
+        err |= __get_user(env->aregs[i], &sc->regs.acrs[i]);
+    }
+    for (i = 0; i < 16; i++) {
+        err |= __get_user(env->fregs[i].ll, &sc->fpregs.fprs[i]);
+    }
+    
+    return err;
+}
+
+long do_sigreturn(CPUState *env)
+{
+    sigframe *frame;
+    abi_ulong frame_addr = env->regs[15];
+    qemu_log("%s: frame_addr 0x%lx\n", __FUNCTION__, frame_addr);
+    target_sigset_t target_set;
+    sigset_t set;
+
+    if (!lock_user_struct(VERIFY_READ, frame, frame_addr, 1))
+            goto badframe;
+    if (__get_user(target_set.sig[0], &frame->sc.oldmask[0]))
+            goto badframe;
+
+    target_to_host_sigset_internal(&set, &target_set);
+    sigprocmask(SIG_SETMASK, &set, NULL);	/* ~_BLOCKABLE? */
+
+    if (restore_sigregs(env, &frame->sregs))
+            goto badframe;
+
+    unlock_user_struct(frame, frame_addr, 0);
+    return env->regs[2];
+
+badframe:
+    unlock_user_struct(frame, frame_addr, 0);
+    force_sig(TARGET_SIGSEGV);
+    return 0;
+}
+
+long do_rt_sigreturn(CPUState *env)
+{
+    rt_sigframe *frame;
+    abi_ulong frame_addr = env->regs[15];
+    qemu_log("%s: frame_addr 0x%lx\n", __FUNCTION__, frame_addr);
+    sigset_t set;
+
+    if (!lock_user_struct(VERIFY_READ, frame, frame_addr, 1))
+            goto badframe;
+    target_to_host_sigset(&set, &frame->uc.uc_sigmask);
+
+    sigprocmask(SIG_SETMASK, &set, NULL);	/* ~_BLOCKABLE? */
+
+    if (restore_sigregs(env, &frame->uc.uc_mcontext))
+            goto badframe;
+
+    if (do_sigaltstack(frame_addr + offsetof(rt_sigframe, uc.uc_stack), 0,
+                       get_sp_from_cpustate(env)) == -EFAULT)
+            goto badframe;
+    unlock_user_struct(frame, frame_addr, 0);
+    return env->regs[2];
+
+badframe:
+    unlock_user_struct(frame, frame_addr, 0);
+    force_sig(TARGET_SIGSEGV);
+    return 0;
+}
+
 #elif defined(TARGET_PPC) && !defined(TARGET_PPC64)
 
 /* FIXME: Many of the structures are defined for both PPC and PPC64, but
diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 45ccef9..617e031 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -5102,7 +5102,7 @@  abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
             ret = get_errno(settimeofday(&tv, NULL));
         }
         break;
-#ifdef TARGET_NR_select
+#if defined(TARGET_NR_select) && !defined(TARGET_S390X) && !defined(TARGET_S390)
     case TARGET_NR_select:
         {
             struct target_sel_arg_struct *sel;
@@ -5209,7 +5209,9 @@  abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
 #endif
 #ifdef TARGET_NR_mmap
     case TARGET_NR_mmap:
-#if (defined(TARGET_I386) && defined(TARGET_ABI32)) || defined(TARGET_ARM) || defined(TARGET_M68K) || defined(TARGET_CRIS) || defined(TARGET_MICROBLAZE)
+#if (defined(TARGET_I386) && defined(TARGET_ABI32)) || defined(TARGET_ARM) || \
+    defined(TARGET_M68K) || defined(TARGET_CRIS) || defined(TARGET_MICROBLAZE) \
+    || defined(TARGET_S390X)
         {
             abi_ulong *v;
             abi_ulong v1, v2, v3, v4, v5, v6;
@@ -5694,6 +5696,8 @@  abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
         ret = get_errno(do_fork(cpu_env, arg1, arg2, arg3, arg5, arg4));
 #elif defined(TARGET_CRIS)
         ret = get_errno(do_fork(cpu_env, arg2, arg1, arg3, arg4, arg5));
+#elif defined(TARGET_S390X)
+        ret = get_errno(do_fork(cpu_env, arg2, arg1, arg3, arg5, arg4));
 #else
         ret = get_errno(do_fork(cpu_env, arg1, arg2, arg3, arg4, arg5));
 #endif
@@ -5898,8 +5902,12 @@  abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
         }
         break;
 #endif /* TARGET_NR_getdents64 */
-#ifdef TARGET_NR__newselect
+#if defined(TARGET_NR__newselect) || defined(TARGET_S390X)
+#ifdef TARGET_S390X
+    case TARGET_NR_select:
+#else
     case TARGET_NR__newselect:
+#endif
         ret = do_select(arg1, arg2, arg3, arg4, arg5);
         break;
 #endif
@@ -6124,7 +6132,7 @@  abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
     case TARGET_NR_sigaltstack:
 #if defined(TARGET_I386) || defined(TARGET_ARM) || defined(TARGET_MIPS) || \
     defined(TARGET_SPARC) || defined(TARGET_PPC) || defined(TARGET_ALPHA) || \
-    defined(TARGET_M68K)
+    defined(TARGET_M68K) || defined(TARGET_S390X)
         ret = do_sigaltstack(arg1, arg2, get_sp_from_cpustate((CPUState *)cpu_env));
         break;
 #else
diff --git a/linux-user/syscall_defs.h b/linux-user/syscall_defs.h
index c018165..2771fae 100644
--- a/linux-user/syscall_defs.h
+++ b/linux-user/syscall_defs.h
@@ -55,7 +55,7 @@ 
 #endif
 
 #if defined(TARGET_I386) || defined(TARGET_ARM) || defined(TARGET_SH4) \
-    || defined(TARGET_M68K) || defined(TARGET_CRIS)
+    || defined(TARGET_M68K) || defined(TARGET_CRIS) || defined(TARGET_S390X)
 
 #define TARGET_IOC_SIZEBITS	14
 #define TARGET_IOC_DIRBITS	2
@@ -315,7 +315,10 @@  struct target_sigaction;
 int do_sigaction(int sig, const struct target_sigaction *act,
                  struct target_sigaction *oact);
 
-#if defined(TARGET_I386) || defined(TARGET_ARM) || defined(TARGET_SPARC) || defined(TARGET_PPC) || defined(TARGET_MIPS) || defined (TARGET_SH4) || defined(TARGET_M68K) || defined(TARGET_ALPHA) || defined(TARGET_CRIS) || defined(TARGET_MICROBLAZE)
+#if defined(TARGET_I386) || defined(TARGET_ARM) || defined(TARGET_SPARC) || \
+    defined(TARGET_PPC) || defined(TARGET_MIPS) || defined (TARGET_SH4) || \
+    defined(TARGET_M68K) || defined(TARGET_ALPHA) || defined(TARGET_CRIS) || \
+    defined(TARGET_MICROBLAZE) || defined(TARGET_S390X)
 
 #if defined(TARGET_SPARC)
 #define TARGET_SA_NOCLDSTOP    8u
@@ -1617,6 +1620,27 @@  struct target_stat {
 
   	abi_long	__unused[3];
 };
+#elif defined(TARGET_S390X)
+struct target_stat {
+    abi_ulong  st_dev;
+    abi_ulong  st_ino;
+    abi_ulong  st_nlink;
+    unsigned int   st_mode;
+    unsigned int   st_uid;
+    unsigned int   st_gid;
+    unsigned int   __pad1;
+    abi_ulong  st_rdev;
+    abi_ulong  st_size;
+    abi_ulong  target_st_atime;
+    abi_ulong  target_st_atime_nsec;
+    abi_ulong  target_st_mtime;
+    abi_ulong  target_st_mtime_nsec;
+    abi_ulong  target_st_ctime;
+    abi_ulong  target_st_ctime_nsec;
+    abi_ulong  st_blksize;
+    abi_long       st_blocks;
+    abi_ulong  __unused[3];
+};
 #else
 #error unsupported CPU
 #endif
@@ -1703,6 +1727,34 @@  struct target_statfs64 {
 	abi_long f_frsize;
 	abi_long f_spare[5];
 };
+#elif defined(TARGET_S390X)
+struct target_statfs {
+    int32_t  f_type;
+    int32_t  f_bsize;
+    abi_long f_blocks;
+    abi_long f_bfree;
+    abi_long f_bavail;
+    abi_long f_files;
+    abi_long f_ffree;
+    kernel_fsid_t f_fsid;
+    int32_t  f_namelen;
+    int32_t  f_frsize;
+    int32_t  f_spare[5];
+};
+
+struct target_statfs64 {
+    int32_t  f_type;
+    int32_t  f_bsize;
+    abi_long f_blocks;
+    abi_long f_bfree;
+    abi_long f_bavail;
+    abi_long f_files;
+    abi_long f_ffree;
+    kernel_fsid_t f_fsid;
+    int32_t  f_namelen;
+    int32_t  f_frsize;
+    int32_t  f_spare[5];
+};
 #else
 struct target_statfs {
 	uint32_t f_type;
diff --git a/qemu-binfmt-conf.sh b/qemu-binfmt-conf.sh
index 941f0cf..5678771 100644
--- a/qemu-binfmt-conf.sh
+++ b/qemu-binfmt-conf.sh
@@ -1,5 +1,5 @@ 
 #!/bin/sh
-# enable automatic i386/ARM/M68K/MIPS/SPARC/PPC program execution by the kernel
+# enable automatic i386/ARM/M68K/MIPS/SPARC/PPC/s390 program execution by the kernel
 
 # load the binfmt_misc module
 if [ ! -d /proc/sys/fs/binfmt_misc ]; then
@@ -57,3 +57,6 @@  if [ $cpu != "mips" ] ; then
     echo   ':mips64:M::\x7fELF\x02\x02\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x08:\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff:/usr/local/bin/qemu-mips64:' > /proc/sys/fs/binfmt_misc/register
     echo   ':mips64el:M::\x7fELF\x02\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x08\x00:\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff:/usr/local/bin/qemu-mips64el:' > /proc/sys/fs/binfmt_misc/register
 fi
+if [ $cpu != "s390x" ] ; then
+    echo   ':s390x:M::\x7fELF\x02\x02\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x16:\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff:/usr/local/bin/qemu-s390x:' > /proc/sys/fs/binfmt_misc/register
+fi