#include <asm/unistd.h>
extern void stub_segv_handler(int sig);
+extern void stub_clone_handler(void);
#define STUB_SYSCALL_RET EAX
#define STUB_MMAP_NR __NR_mmap2
#define MMAP_OFFSET(o) ((o) >> PAGE_SHIFT)
+static inline long stub_syscall2(long syscall, long arg1, long arg2)
+{
+ long ret;
+
+ __asm__("movl %0, %%ecx; " : : "g" (arg2) : "%ecx");
+ __asm__("movl %0, %%ebx; " : : "g" (arg1) : "%ebx");
+ __asm__("movl %0, %%eax; " : : "g" (syscall) : "%eax");
+ __asm__("int $0x80;" : : : "%eax");
+ __asm__ __volatile__("movl %%eax, %0; " : "=g" (ret) :);
+ return(ret);
+}
+
+static inline long stub_syscall3(long syscall, long arg1, long arg2, long arg3)
+{
+ __asm__("movl %0, %%edx; " : : "g" (arg3) : "%edx");
+ return(stub_syscall2(syscall, arg1, arg2));
+}
+
+static inline long stub_syscall4(long syscall, long arg1, long arg2, long arg3,
+ long arg4)
+{
+ __asm__("movl %0, %%esi; " : : "g" (arg4) : "%esi");
+ return(stub_syscall3(syscall, arg1, arg2, arg3));
+}
+
+static inline long stub_syscall6(long syscall, long arg1, long arg2, long arg3,
+ long arg4, long arg5, long arg6)
+{
+ long ret;
+ __asm__("movl %0, %%eax; " : : "g" (syscall) : "%eax");
+ __asm__("movl %0, %%ebx; " : : "g" (arg1) : "%ebx");
+ __asm__("movl %0, %%ecx; " : : "g" (arg2) : "%ecx");
+ __asm__("movl %0, %%edx; " : : "g" (arg3) : "%edx");
+ __asm__("movl %0, %%esi; " : : "g" (arg4) : "%esi");
+ __asm__("movl %0, %%edi; " : : "g" (arg5) : "%edi");
+ __asm__ __volatile__("pushl %%ebp ; movl %1, %%ebp; "
+ "int $0x80; popl %%ebp ; "
+ "movl %%eax, %0; " : "=g" (ret) : "g" (arg6) : "%eax");
+ return(ret);
+}
+
+static inline void trap_myself(void)
+{
+ __asm("int3");
+}
+
#endif
#include <sysdep/ptrace_user.h>
extern void stub_segv_handler(int sig);
+extern void stub_clone_handler(void);
#define STUB_SYSCALL_RET PT_INDEX(RAX)
#define STUB_MMAP_NR __NR_mmap
#define MMAP_OFFSET(o) (o)
+static inline long stub_syscall2(long syscall, long arg1, long arg2)
+{
+ long ret;
+
+ __asm__("movq %0, %%rsi; " : : "g" (arg2) : "%rsi");
+ __asm__("movq %0, %%rdi; " : : "g" (arg1) : "%rdi");
+ __asm__("movq %0, %%rax; " : : "g" (syscall) : "%rax");
+ __asm__("syscall;" : : : "%rax", "%r11", "%rcx");
+ __asm__ __volatile__("movq %%rax, %0; " : "=g" (ret) :);
+ return(ret);
+}
+
+static inline long stub_syscall3(long syscall, long arg1, long arg2, long arg3)
+{
+ __asm__("movq %0, %%rdx; " : : "g" (arg3) : "%rdx");
+ return(stub_syscall2(syscall, arg1, arg2));
+}
+
+static inline long stub_syscall4(long syscall, long arg1, long arg2, long arg3,
+ long arg4)
+{
+ __asm__("movq %0, %%r10; " : : "g" (arg4) : "%r10");
+ return(stub_syscall3(syscall, arg1, arg2, arg3));
+}
+
+static inline long stub_syscall6(long syscall, long arg1, long arg2, long arg3,
+ long arg4, long arg5, long arg6)
+{
+ __asm__("movq %0, %%r9; " : : "g" (arg6) : "%r9");
+ __asm__("movq %0, %%r8; " : : "g" (arg5) : "%r8");
+ return(stub_syscall4(syscall, arg1, arg2, arg3, arg4));
+}
+
+static inline void trap_myself(void)
+{
+ __asm("int3");
+}
+
#endif
extern void switch_timers(int to_real);
extern void idle_sleep(int secs);
extern void enable_timer(void);
+extern void prepare_timer(void * ptr);
extern void disable_timer(void);
extern unsigned long time_lock(void);
extern void time_unlock(unsigned long);
# Licensed under the GPL
#
-obj-y := exec_kern.o mem.o mem_user.o mmu.o process.o process_kern.o \
+obj-y := clone.o exec_kern.o mem.o mem_user.o mmu.o process.o process_kern.o \
syscall_kern.o syscall_user.o tlb.o trap_user.o uaccess.o \
subdir- := util
-USER_OBJS := process.o
+USER_OBJS := process.o clone.o
include arch/um/scripts/Makefile.rules
+
+# clone.o is in the stub, so it can't be built with profiling
+$(obj)/clone.o : c_flags = -Wp,-MD,$(depfile) $(call unprofile,$(USER_CFLAGS))
--- /dev/null
+#include <sched.h>
+#include <signal.h>
+#include <sys/mman.h>
+#include <sys/time.h>
+#include <asm/unistd.h>
+#include <asm/page.h>
+#include "ptrace_user.h"
+#include "skas.h"
+#include "stub-data.h"
+#include "uml-config.h"
+#include "sysdep/stub.h"
+
+/* This is in a separate file because it needs to be compiled with any
+ * extraneous gcc flags (-pg, -fprofile-arcs, -ftest-coverage) disabled
+ */
+void __attribute__ ((__section__ (".__syscall_stub")))
+stub_clone_handler(void)
+{
+ long err;
+ struct stub_data *from = (struct stub_data *) UML_CONFIG_STUB_DATA;
+
+ err = stub_syscall2(__NR_clone, CLONE_PARENT | CLONE_FILES | SIGCHLD,
+ UML_CONFIG_STUB_DATA + PAGE_SIZE / 2 -
+ sizeof(void *));
+ if(err != 0)
+ goto out;
+
+ err = stub_syscall4(__NR_ptrace, PTRACE_TRACEME, 0, 0, 0);
+ if(err)
+ goto out;
+
+ err = stub_syscall3(__NR_setitimer, ITIMER_VIRTUAL,
+ (long) &from->timer, 0);
+ if(err)
+ goto out;
+
+ err = stub_syscall6(STUB_MMAP_NR, UML_CONFIG_STUB_DATA, PAGE_SIZE,
+ PROT_READ | PROT_WRITE, MAP_FIXED | MAP_SHARED,
+ from->fd, from->offset);
+ out:
+ /* save current result. Parent: pid; child: retcode of mmap */
+ from->err = err;
+ trap_myself();
+}
extern void user_signal(int sig, union uml_pt_regs *regs, int pid);
extern int new_mm(int from);
extern int start_userspace(unsigned long stub_stack);
+extern int copy_context_skas0(unsigned long stack, int pid);
extern void get_skas_faultinfo(int pid, struct faultinfo * fi);
extern long execute_syscall_skas(void *r);
extern unsigned long current_stub_stack(void);
--- /dev/null
+/*
+ * Copyright (C) 2005 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#ifndef __STUB_DATA_H
+#define __STUB_DATA_H
+
+#include <sys/time.h>
+
+struct stub_data {
+ long offset;
+ int fd;
+ struct itimerval timer;
+ long err;
+};
+
+#endif
int init_new_context_skas(struct task_struct *task, struct mm_struct *mm)
{
struct mm_struct *cur_mm = current->mm;
+ struct mm_id *cur_mm_id = &cur_mm->context.skas.id;
struct mm_id *mm_id = &mm->context.skas.id;
unsigned long stack;
int from, ret;
goto out_free;
mm->nr_ptes--;
- mm_id->u.pid = start_userspace(stack);
+
+ if((cur_mm != NULL) && (cur_mm != &init_mm))
+ mm_id->u.pid = copy_context_skas0(stack,
+ cur_mm_id->u.pid);
+ else mm_id->u.pid = start_userspace(stack);
}
return 0;
#include <sys/wait.h>
#include <sys/mman.h>
#include <sys/user.h>
+#include <sys/time.h>
#include <asm/unistd.h>
#include <asm/types.h>
#include "user.h"
#include "user_util.h"
#include "kern_util.h"
#include "skas.h"
+#include "stub-data.h"
#include "mm_id.h"
#include "sysdep/sigcontext.h"
#include "sysdep/stub.h"
#define INIT_JMP_HALT 3
#define INIT_JMP_REBOOT 4
+
+int copy_context_skas0(unsigned long new_stack, int pid)
+{
+ int err;
+ unsigned long regs[MAX_REG_NR];
+ unsigned long current_stack = current_stub_stack();
+ struct stub_data *data = (struct stub_data *) current_stack;
+ struct stub_data *child_data = (struct stub_data *) new_stack;
+ __u64 new_offset;
+ int new_fd = phys_mapping(to_phys((void *)new_stack), &new_offset);
+
+ /* prepare offset and fd of child's stack as argument for parent's
+ * and child's mmap2 calls
+ */
+ *data = ((struct stub_data) { .offset = MMAP_OFFSET(new_offset),
+ .fd = new_fd,
+ .timer = ((struct itimerval)
+ { { 0, 1000000 / hz() },
+ { 0, 1000000 / hz() }})});
+ get_safe_registers(regs);
+
+ /* Set parent's instruction pointer to start of clone-stub */
+ regs[REGS_IP_INDEX] = UML_CONFIG_STUB_CODE +
+ (unsigned long) stub_clone_handler -
+ (unsigned long) &__syscall_stub_start;
+ regs[REGS_SP_INDEX] = UML_CONFIG_STUB_DATA + PAGE_SIZE -
+ sizeof(void *);
+ err = ptrace_setregs(pid, regs);
+ if(err < 0)
+ panic("copy_context_skas0 : PTRACE_SETREGS failed, "
+ "pid = %d, errno = %d\n", pid, errno);
+
+ /* set a well known return code for detection of child write failure */
+ child_data->err = 12345678;
+
+ /* Wait, until parent has finished its work: read child's pid from
+ * parent's stack, and check, if bad result.
+ */
+ wait_stub_done(pid, 0, "copy_context_skas0");
+
+ pid = data->err;
+ if(pid < 0)
+ panic("copy_context_skas0 - stub-parent reports error %d\n",
+ pid);
+
+ /* Wait, until child has finished too: read child's result from
+ * child's stack and check it.
+ */
+ wait_stub_done(pid, -1, "copy_context_skas0");
+ if (child_data->err != UML_CONFIG_STUB_DATA)
+ panic("copy_context_skas0 - stub-child reports error %d\n",
+ child_data->err);
+
+ if (ptrace(PTRACE_OLDSETOPTIONS, pid, NULL,
+ (void *)PTRACE_O_TRACESYSGOOD) < 0)
+ panic("copy_context_skas0 : PTRACE_SETOPTIONS failed, "
+ "errno = %d\n", errno);
+
+ return pid;
+}
+
void new_thread(void *stack, void **switch_buf_ptr, void **fork_buf_ptr,
void (*handler)(int))
{
set_interval(ITIMER_VIRTUAL);
}
+void prepare_timer(void * ptr)
+{
+ int usec = 1000000/hz();
+ *(struct itimerval *)ptr = ((struct itimerval) { { 0, usec },
+ { 0, usec }});
+}
+
void disable_timer(void)
{
struct itimerval disable = ((struct itimerval) { { 0, 0 }, { 0, 0 }});