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authorGennady Sharapov <gennady.v.sharapov@intel.com>2005-09-03 15:57:47 -0700
committerLinus Torvalds <torvalds@evo.osdl.org>2005-09-05 00:06:24 -0700
commit60d339f6fe0831060600c62418b71a62ad26c281 (patch)
treea2f9527bbcfe85b3eb7c063b8af7d2f499ba4cbb /arch
parent09ace81c1d737bcbb2423db235ac980cac4d5de9 (diff)
[PATCH] uml: move libc-dependent startup and signal code
The serial UML OS-abstraction layer patch (um/kernel dir). This moves all systemcalls from process.c file under os-Linux dir and join process.c and process_kern.c files. Signed-off-by: Gennady Sharapov <gennady.v.sharapov@intel.com> Signed-off-by: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'arch')
-rw-r--r--arch/um/include/os.h15
-rw-r--r--arch/um/include/user_util.h8
-rw-r--r--arch/um/kernel/Makefile13
-rw-r--r--arch/um/kernel/um_arch.c2
-rw-r--r--arch/um/os-Linux/Makefile7
-rw-r--r--arch/um/os-Linux/process.c58
-rw-r--r--arch/um/os-Linux/start_up.c (renamed from arch/um/kernel/process.c)182
-rw-r--r--arch/um/os-Linux/tt.c113
8 files changed, 230 insertions, 168 deletions
diff --git a/arch/um/include/os.h b/arch/um/include/os.h
index 881d2988d2d..4c362458052 100644
--- a/arch/um/include/os.h
+++ b/arch/um/include/os.h
@@ -153,6 +153,11 @@ extern int os_file_type(char *file);
extern int os_file_mode(char *file, struct openflags *mode_out);
extern int os_lock_file(int fd, int excl);
+/* start_up.c */
+extern void os_early_checks(void);
+extern int can_do_skas(void);
+
+/* process.c */
extern unsigned long os_process_pc(int pid);
extern int os_process_parent(int pid);
extern void os_stop_process(int pid);
@@ -161,6 +166,9 @@ extern void os_kill_ptraced_process(int pid, int reap_child);
extern void os_usr1_process(int pid);
extern int os_getpid(void);
extern int os_getpgrp(void);
+extern void init_new_thread_stack(void *sig_stack, void (*usr1_handler)(int));
+extern void init_new_thread_signals(int altstack);
+extern int run_kernel_thread(int (*fn)(void *), void *arg, void **jmp_ptr);
extern int os_map_memory(void *virt, int fd, unsigned long long off,
unsigned long len, int r, int w, int x);
@@ -170,6 +178,13 @@ extern int os_unmap_memory(void *addr, int len);
extern void os_flush_stdout(void);
extern unsigned long long os_usecs(void);
+/* tt.c
+ * for tt mode only (will be deleted in future...)
+ */
+extern void forward_pending_sigio(int target);
+extern int start_fork_tramp(void *arg, unsigned long temp_stack,
+ int clone_flags, int (*tramp)(void *));
+
#endif
/*
diff --git a/arch/um/include/user_util.h b/arch/um/include/user_util.h
index 7b6a24dfd30..bb505e01d99 100644
--- a/arch/um/include/user_util.h
+++ b/arch/um/include/user_util.h
@@ -54,8 +54,6 @@ extern void stack_protections(unsigned long address);
extern void task_protections(unsigned long address);
extern int wait_for_stop(int pid, int sig, int cont_type, void *relay);
extern void *add_signal_handler(int sig, void (*handler)(int));
-extern int start_fork_tramp(void *arg, unsigned long temp_stack,
- int clone_flags, int (*tramp)(void *));
extern int linux_main(int argc, char **argv);
extern void set_cmdline(char *cmd);
extern void input_cb(void (*proc)(void *), void *arg, int arg_len);
@@ -64,8 +62,6 @@ extern void *um_kmalloc(int size);
extern int switcheroo(int fd, int prot, void *from, void *to, int size);
extern void setup_machinename(char *machine_out);
extern void setup_hostinfo(void);
-extern void init_new_thread_stack(void *sig_stack, void (*usr1_handler)(int));
-extern void init_new_thread_signals(int altstack);
extern void do_exec(int old_pid, int new_pid);
extern void tracer_panic(char *msg, ...);
extern char *get_umid(int only_if_set);
@@ -74,16 +70,12 @@ extern int detach(int pid, int sig);
extern int attach(int pid);
extern void kill_child_dead(int pid);
extern int cont(int pid);
-extern void check_ptrace(void);
extern void check_sigio(void);
-extern int run_kernel_thread(int (*fn)(void *), void *arg, void **jmp_ptr);
extern void write_sigio_workaround(void);
extern void arch_check_bugs(void);
extern int cpu_feature(char *what, char *buf, int len);
extern int arch_handle_signal(int sig, union uml_pt_regs *regs);
extern int arch_fixup(unsigned long address, void *sc_ptr);
-extern void forward_pending_sigio(int target);
-extern int can_do_skas(void);
extern void arch_init_thread(void);
extern int setjmp_wrapper(void (*proc)(void *, void *), ...);
extern int raw(int fd);
diff --git a/arch/um/kernel/Makefile b/arch/um/kernel/Makefile
index a9cdd00775a..614b8ebeb0e 100644
--- a/arch/um/kernel/Makefile
+++ b/arch/um/kernel/Makefile
@@ -8,11 +8,10 @@ clean-files :=
obj-y = config.o exec_kern.o exitcode.o \
helper.o init_task.o irq.o irq_user.o ksyms.o main.o mem.o mem_user.o \
- physmem.o process.o process_kern.o ptrace.o reboot.o resource.o \
- sigio_user.o sigio_kern.o signal_kern.o signal_user.o smp.o \
- syscall_kern.o sysrq.o tempfile.o time.o time_kern.o \
- tlb.o trap_kern.o trap_user.o uaccess_user.o um_arch.o umid.o \
- user_util.o
+ physmem.o process_kern.o ptrace.o reboot.o resource.o sigio_user.o \
+ sigio_kern.o signal_kern.o signal_user.o smp.o syscall_kern.o sysrq.o \
+ tempfile.o time.o time_kern.o tlb.o trap_kern.o trap_user.o \
+ uaccess_user.o um_arch.o umid.o user_util.o
obj-$(CONFIG_BLK_DEV_INITRD) += initrd.o
obj-$(CONFIG_GPROF) += gprof_syms.o
@@ -25,8 +24,8 @@ obj-$(CONFIG_MODE_SKAS) += skas/
user-objs-$(CONFIG_TTY_LOG) += tty_log.o
-USER_OBJS := $(user-objs-y) config.o helper.o main.o process.o tempfile.o \
- time.o tty_log.o umid.o user_util.o
+USER_OBJS := $(user-objs-y) config.o helper.o main.o tempfile.o time.o \
+ tty_log.o umid.o user_util.o
include arch/um/scripts/Makefile.rules
diff --git a/arch/um/kernel/um_arch.c b/arch/um/kernel/um_arch.c
index b781b6f9428..09f6f7ce469 100644
--- a/arch/um/kernel/um_arch.c
+++ b/arch/um/kernel/um_arch.c
@@ -333,6 +333,7 @@ int linux_main(int argc, char **argv)
if(have_root == 0)
add_arg(DEFAULT_COMMAND_LINE);
+ os_early_checks();
mode_tt = force_tt ? 1 : !can_do_skas();
#ifndef CONFIG_MODE_TT
if (mode_tt) {
@@ -470,7 +471,6 @@ void __init setup_arch(char **cmdline_p)
void __init check_bugs(void)
{
arch_check_bugs();
- check_ptrace();
check_sigio();
check_devanon();
}
diff --git a/arch/um/os-Linux/Makefile b/arch/um/os-Linux/Makefile
index 351d9693467..d3c1560e3ed 100644
--- a/arch/um/os-Linux/Makefile
+++ b/arch/um/os-Linux/Makefile
@@ -3,10 +3,11 @@
# Licensed under the GPL
#
-obj-y = aio.o elf_aux.o file.o process.o signal.o time.o tty.o user_syms.o \
- drivers/ sys-$(SUBARCH)/
+obj-y = aio.o elf_aux.o file.o process.o signal.o start_up.o time.o tt.o \
+ tty.o user_syms.o drivers/ sys-$(SUBARCH)/
-USER_OBJS := aio.o elf_aux.o file.o process.o signal.o time.o tty.o
+USER_OBJS := aio.o elf_aux.o file.o process.o signal.o start_up.o time.o tt.o \
+ tty.o
CFLAGS_user_syms.o += -DSUBARCH_$(SUBARCH)
diff --git a/arch/um/os-Linux/process.c b/arch/um/os-Linux/process.c
index 1e126bfd31a..d32413e4b4c 100644
--- a/arch/um/os-Linux/process.c
+++ b/arch/um/os-Linux/process.c
@@ -3,10 +3,10 @@
* Licensed under the GPL
*/
-#include <unistd.h>
#include <stdio.h>
#include <errno.h>
#include <signal.h>
+#include <setjmp.h>
#include <linux/unistd.h>
#include <sys/mman.h>
#include <sys/wait.h>
@@ -14,6 +14,10 @@
#include "os.h"
#include "user.h"
#include "user_util.h"
+#include "signal_user.h"
+#include "process.h"
+#include "irq_user.h"
+#include "kern_util.h"
#define ARBITRARY_ADDR -1
#define FAILURE_PID -1
@@ -114,8 +118,10 @@ void os_usr1_process(int pid)
kill(pid, SIGUSR1);
}
-/*Don't use the glibc version, which caches the result in TLS. It misses some
- * syscalls, and also breaks with clone(), which does not unshare the TLS.*/
+/* Don't use the glibc version, which caches the result in TLS. It misses some
+ * syscalls, and also breaks with clone(), which does not unshare the TLS.
+ */
+
inline _syscall0(pid_t, getpid)
int os_getpid(void)
@@ -164,6 +170,52 @@ int os_unmap_memory(void *addr, int len)
return(0);
}
+void init_new_thread_stack(void *sig_stack, void (*usr1_handler)(int))
+{
+ int flags = 0, pages;
+
+ if(sig_stack != NULL){
+ pages = (1 << UML_CONFIG_KERNEL_STACK_ORDER);
+ set_sigstack(sig_stack, pages * page_size());
+ flags = SA_ONSTACK;
+ }
+ if(usr1_handler) set_handler(SIGUSR1, usr1_handler, flags, -1);
+}
+
+void init_new_thread_signals(int altstack)
+{
+ int flags = altstack ? SA_ONSTACK : 0;
+
+ set_handler(SIGSEGV, (__sighandler_t) sig_handler, flags,
+ SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);
+ set_handler(SIGTRAP, (__sighandler_t) sig_handler, flags,
+ SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);
+ set_handler(SIGFPE, (__sighandler_t) sig_handler, flags,
+ SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);
+ set_handler(SIGILL, (__sighandler_t) sig_handler, flags,
+ SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);
+ set_handler(SIGBUS, (__sighandler_t) sig_handler, flags,
+ SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);
+ set_handler(SIGUSR2, (__sighandler_t) sig_handler,
+ flags, SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);
+ signal(SIGHUP, SIG_IGN);
+
+ init_irq_signals(altstack);
+}
+
+int run_kernel_thread(int (*fn)(void *), void *arg, void **jmp_ptr)
+{
+ sigjmp_buf buf;
+ int n;
+
+ *jmp_ptr = &buf;
+ n = sigsetjmp(buf, 1);
+ if(n != 0)
+ return(n);
+ (*fn)(arg);
+ return(0);
+}
+
/*
* Overrides for Emacs so that we follow Linus's tabbing style.
* Emacs will notice this stuff at the end of the file and automatically
diff --git a/arch/um/kernel/process.c b/arch/um/os-Linux/start_up.c
index 67acd92c532..a3eab25f379 100644
--- a/arch/um/kernel/process.c
+++ b/arch/um/os-Linux/start_up.c
@@ -1,4 +1,4 @@
-/*
+/*
* Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
* Licensed under the GPL
*/
@@ -19,7 +19,6 @@
#include "user_util.h"
#include "kern_util.h"
#include "user.h"
-#include "process.h"
#include "signal_kern.h"
#include "signal_user.h"
#include "sysdep/ptrace.h"
@@ -39,98 +38,6 @@
#include "registers.h"
#endif
-void init_new_thread_stack(void *sig_stack, void (*usr1_handler)(int))
-{
- int flags = 0, pages;
-
- if(sig_stack != NULL){
- pages = (1 << UML_CONFIG_KERNEL_STACK_ORDER);
- set_sigstack(sig_stack, pages * page_size());
- flags = SA_ONSTACK;
- }
- if(usr1_handler) set_handler(SIGUSR1, usr1_handler, flags, -1);
-}
-
-void init_new_thread_signals(int altstack)
-{
- int flags = altstack ? SA_ONSTACK : 0;
-
- set_handler(SIGSEGV, (__sighandler_t) sig_handler, flags,
- SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);
- set_handler(SIGTRAP, (__sighandler_t) sig_handler, flags,
- SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);
- set_handler(SIGFPE, (__sighandler_t) sig_handler, flags,
- SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);
- set_handler(SIGILL, (__sighandler_t) sig_handler, flags,
- SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);
- set_handler(SIGBUS, (__sighandler_t) sig_handler, flags,
- SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);
- set_handler(SIGUSR2, (__sighandler_t) sig_handler,
- flags, SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);
- signal(SIGHUP, SIG_IGN);
-
- init_irq_signals(altstack);
-}
-
-struct tramp {
- int (*tramp)(void *);
- void *tramp_data;
- unsigned long temp_stack;
- int flags;
- int pid;
-};
-
-/* See above for why sigkill is here */
-
-int sigkill = SIGKILL;
-
-int outer_tramp(void *arg)
-{
- struct tramp *t;
- int sig = sigkill;
-
- t = arg;
- t->pid = clone(t->tramp, (void *) t->temp_stack + page_size()/2,
- t->flags, t->tramp_data);
- if(t->pid > 0) wait_for_stop(t->pid, SIGSTOP, PTRACE_CONT, NULL);
- kill(os_getpid(), sig);
- _exit(0);
-}
-
-int start_fork_tramp(void *thread_arg, unsigned long temp_stack,
- int clone_flags, int (*tramp)(void *))
-{
- struct tramp arg;
- unsigned long sp;
- int new_pid, status, err;
-
- /* The trampoline will run on the temporary stack */
- sp = stack_sp(temp_stack);
-
- clone_flags |= CLONE_FILES | SIGCHLD;
-
- arg.tramp = tramp;
- arg.tramp_data = thread_arg;
- arg.temp_stack = temp_stack;
- arg.flags = clone_flags;
-
- /* Start the process and wait for it to kill itself */
- new_pid = clone(outer_tramp, (void *) sp, clone_flags, &arg);
- if(new_pid < 0)
- return(new_pid);
-
- CATCH_EINTR(err = waitpid(new_pid, &status, 0));
- if(err < 0)
- panic("Waiting for outer trampoline failed - errno = %d",
- errno);
-
- if(!WIFSIGNALED(status) || (WTERMSIG(status) != SIGKILL))
- panic("outer trampoline didn't exit with SIGKILL, "
- "status = %d", status);
-
- return(arg.pid);
-}
-
static int ptrace_child(void *arg)
{
int ret;
@@ -165,7 +72,7 @@ static int start_ptraced_child(void **stack_out)
void *stack;
unsigned long sp;
int pid, n, status;
-
+
stack = mmap(NULL, PAGE_SIZE, PROT_READ | PROT_WRITE | PROT_EXEC,
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
if(stack == MAP_FAILED)
@@ -173,10 +80,10 @@ static int start_ptraced_child(void **stack_out)
sp = (unsigned long) stack + PAGE_SIZE - sizeof(void *);
pid = clone(ptrace_child, (void *) sp, SIGCHLD, NULL);
if(pid < 0)
- panic("check_ptrace : clone failed, errno = %d", errno);
+ panic("start_ptraced_child : clone failed, errno = %d", errno);
CATCH_EINTR(n = waitpid(pid, &status, WUNTRACED));
if(n < 0)
- panic("check_ptrace : wait failed, errno = %d", errno);
+ panic("check_ptrace : clone failed, errno = %d", errno);
if(!WIFSTOPPED(status) || (WSTOPSIG(status) != SIGSTOP))
panic("check_ptrace : expected SIGSTOP, got status = %d",
status);
@@ -185,11 +92,14 @@ static int start_ptraced_child(void **stack_out)
return(pid);
}
-/* When testing for SYSEMU support, if it is one of the broken versions, we must
- * just avoid using sysemu, not panic, but only if SYSEMU features are broken.
+/* When testing for SYSEMU support, if it is one of the broken versions, we
+ * must just avoid using sysemu, not panic, but only if SYSEMU features are
+ * broken.
* So only for SYSEMU features we test mustpanic, while normal host features
- * must work anyway!*/
-static int stop_ptraced_child(int pid, void *stack, int exitcode, int mustpanic)
+ * must work anyway!
+ */
+static int stop_ptraced_child(int pid, void *stack, int exitcode,
+ int mustpanic)
{
int status, n, ret = 0;
@@ -217,8 +127,6 @@ static int stop_ptraced_child(int pid, void *stack, int exitcode, int mustpanic)
return ret;
}
-static int force_sysemu_disabled = 0;
-
int ptrace_faultinfo = 1;
int proc_mm = 1;
@@ -228,24 +136,27 @@ static int __init skas0_cmd_param(char *str, int* add)
return 0;
}
+__uml_setup("skas0", skas0_cmd_param,
+ "skas0\n"
+ " Disables SKAS3 usage, so that SKAS0 is used, unless \n"
+ " you specify mode=tt.\n\n");
+
+static int force_sysemu_disabled = 0;
+
static int __init nosysemu_cmd_param(char *str, int* add)
{
force_sysemu_disabled = 1;
return 0;
}
-__uml_setup("skas0", skas0_cmd_param,
- "skas0\n"
- " Disables SKAS3 usage, so that SKAS0 is used, unless you \n"
- " specify mode=tt.\n\n");
-
__uml_setup("nosysemu", nosysemu_cmd_param,
- "nosysemu\n"
- " Turns off syscall emulation patch for ptrace (SYSEMU) on.\n"
- " SYSEMU is a performance-patch introduced by Laurent Vivier. It changes\n"
- " behaviour of ptrace() and helps reducing host context switch rate.\n"
- " To make it working, you need a kernel patch for your host, too.\n"
- " See http://perso.wanadoo.fr/laurent.vivier/UML/ for further information.\n\n");
+"nosysemu\n"
+" Turns off syscall emulation patch for ptrace (SYSEMU) on.\n"
+" SYSEMU is a performance-patch introduced by Laurent Vivier. It changes\n"
+" behaviour of ptrace() and helps reducing host context switch rate.\n"
+" To make it working, you need a kernel patch for your host, too.\n"
+" See http://perso.wanadoo.fr/laurent.vivier/UML/ for further \n"
+" information.\n\n");
static void __init check_sysemu(void)
{
@@ -321,7 +232,7 @@ fail_stopped:
printk("missing\n");
}
-void __init check_ptrace(void)
+static void __init check_ptrace(void)
{
void *stack;
int pid, syscall, n, status;
@@ -329,12 +240,12 @@ void __init check_ptrace(void)
printk("Checking that ptrace can change system call numbers...");
pid = start_ptraced_child(&stack);
- if (ptrace(PTRACE_OLDSETOPTIONS, pid, 0, (void *)PTRACE_O_TRACESYSGOOD) < 0)
- panic("check_ptrace: PTRACE_SETOPTIONS failed, errno = %d", errno);
+ if(ptrace(PTRACE_OLDSETOPTIONS, pid, 0, (void *)PTRACE_O_TRACESYSGOOD) < 0)
+ panic("check_ptrace: PTRACE_OLDSETOPTIONS failed, errno = %d", errno);
while(1){
if(ptrace(PTRACE_SYSCALL, pid, 0, 0) < 0)
- panic("check_ptrace : ptrace failed, errno = %d",
+ panic("check_ptrace : ptrace failed, errno = %d",
errno);
CATCH_EINTR(n = waitpid(pid, &status, WUNTRACED));
if(n < 0)
@@ -342,7 +253,7 @@ void __init check_ptrace(void)
if(!WIFSTOPPED(status) || (WSTOPSIG(status) != SIGTRAP + 0x80))
panic("check_ptrace : expected SIGTRAP + 0x80, "
"got status = %d", status);
-
+
syscall = ptrace(PTRACE_PEEKUSR, pid, PT_SYSCALL_NR_OFFSET,
0);
if(syscall == __NR_getpid){
@@ -359,33 +270,12 @@ void __init check_ptrace(void)
check_sysemu();
}
-int run_kernel_thread(int (*fn)(void *), void *arg, void **jmp_ptr)
-{
- sigjmp_buf buf;
- int n;
-
- *jmp_ptr = &buf;
- n = sigsetjmp(buf, 1);
- if(n != 0)
- return(n);
- (*fn)(arg);
- return(0);
-}
-
-void forward_pending_sigio(int target)
+void os_early_checks(void)
{
- sigset_t sigs;
-
- if(sigpending(&sigs))
- panic("forward_pending_sigio : sigpending failed");
- if(sigismember(&sigs, SIGIO))
- kill(target, SIGIO);
+ check_ptrace();
}
-extern void *__syscall_stub_start, __syscall_stub_end;
-
#ifdef UML_CONFIG_MODE_SKAS
-
static inline void check_skas3_ptrace_support(void)
{
struct ptrace_faultinfo fi;
@@ -400,9 +290,8 @@ static inline void check_skas3_ptrace_support(void)
ptrace_faultinfo = 0;
if(errno == EIO)
printf("not found\n");
- else {
+ else
perror("not found");
- }
}
else {
if (!ptrace_faultinfo)
@@ -419,9 +308,10 @@ int can_do_skas(void)
{
printf("Checking for /proc/mm...");
if (os_access("/proc/mm", OS_ACC_W_OK) < 0) {
- proc_mm = 0;
+ proc_mm = 0;
printf("not found\n");
- } else {
+ }
+ else {
if (!proc_mm)
printf("found but disabled on command line\n");
else
diff --git a/arch/um/os-Linux/tt.c b/arch/um/os-Linux/tt.c
new file mode 100644
index 00000000000..5b047ab8416
--- /dev/null
+++ b/arch/um/os-Linux/tt.c
@@ -0,0 +1,113 @@
+/*
+ * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#include <stdio.h>
+#include <unistd.h>
+#include <signal.h>
+#include <sched.h>
+#include <errno.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <setjmp.h>
+#include <sys/time.h>
+#include <sys/ptrace.h>
+#include <linux/ptrace.h>
+#include <sys/wait.h>
+#include <sys/mman.h>
+#include <asm/ptrace.h>
+#include <asm/unistd.h>
+#include <asm/page.h>
+#include "user_util.h"
+#include "kern_util.h"
+#include "user.h"
+#include "signal_kern.h"
+#include "signal_user.h"
+#include "sysdep/ptrace.h"
+#include "sysdep/sigcontext.h"
+#include "irq_user.h"
+#include "ptrace_user.h"
+#include "time_user.h"
+#include "init.h"
+#include "os.h"
+#include "uml-config.h"
+#include "choose-mode.h"
+#include "mode.h"
+#include "tempfile.h"
+
+/*
+ *-------------------------
+ * only for tt mode (will be deleted in future...)
+ *-------------------------
+ */
+
+struct tramp {
+ int (*tramp)(void *);
+ void *tramp_data;
+ unsigned long temp_stack;
+ int flags;
+ int pid;
+};
+
+/* See above for why sigkill is here */
+
+int sigkill = SIGKILL;
+
+int outer_tramp(void *arg)
+{
+ struct tramp *t;
+ int sig = sigkill;
+
+ t = arg;
+ t->pid = clone(t->tramp, (void *) t->temp_stack + page_size()/2,
+ t->flags, t->tramp_data);
+ if(t->pid > 0) wait_for_stop(t->pid, SIGSTOP, PTRACE_CONT, NULL);
+ kill(os_getpid(), sig);
+ _exit(0);
+}
+
+int start_fork_tramp(void *thread_arg, unsigned long temp_stack,
+ int clone_flags, int (*tramp)(void *))
+{
+ struct tramp arg;
+ unsigned long sp;
+ int new_pid, status, err;
+
+ /* The trampoline will run on the temporary stack */
+ sp = stack_sp(temp_stack);
+
+ clone_flags |= CLONE_FILES | SIGCHLD;
+
+ arg.tramp = tramp;
+ arg.tramp_data = thread_arg;
+ arg.temp_stack = temp_stack;
+ arg.flags = clone_flags;
+
+ /* Start the process and wait for it to kill itself */
+ new_pid = clone(outer_tramp, (void *) sp, clone_flags, &arg);
+ if(new_pid < 0)
+ return(new_pid);
+
+ CATCH_EINTR(err = waitpid(new_pid, &status, 0));
+ if(err < 0)
+ panic("Waiting for outer trampoline failed - errno = %d",
+ errno);
+
+ if(!WIFSIGNALED(status) || (WTERMSIG(status) != SIGKILL))
+ panic("outer trampoline didn't exit with SIGKILL, "
+ "status = %d", status);
+
+ return(arg.pid);
+}
+
+void forward_pending_sigio(int target)
+{
+ sigset_t sigs;
+
+ if(sigpending(&sigs))
+ panic("forward_pending_sigio : sigpending failed");
+ if(sigismember(&sigs, SIGIO))
+ kill(target, SIGIO);
+}
+