[PATCH] uml: fix syscall table by including $(SUBARCH)'s one, for x86-64

Reuse asm-x86-64/unistd.h to build our syscall table, like x86-64 already
does.

Like for i386, we must add some #defines for all the (right!) changes UML does
to x86-64 syscall table.

Note: I noted a bogus:
	[ __NR_sched_yield ] = (syscall_handler_t *) yield,

while doing this patch (which could only be a workaround for some strange bug,
but I would ignore this possibility).  I'm changing this without notice.
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

arch/um/include/sysdep-x86_64/syscalls.h

@@ -30,51 +30,6 @@ extern syscall_handler_t wrap_sys_shmat;
 extern syscall_handler_t sys_modify_ldt;
 extern syscall_handler_t sys_arch_prctl;
 
-#define ARCH_SYSCALLS \
-	[ __NR_mmap ] = (syscall_handler_t *) old_mmap, \
-	[ __NR_select ] = (syscall_handler_t *) sys_select, \
-	[ __NR_mincore ] = (syscall_handler_t *) sys_mincore, \
-	[ __NR_madvise ] = (syscall_handler_t *) sys_madvise, \
-	[ __NR_shmget ] = (syscall_handler_t *) sys_shmget, \
-	[ __NR_shmat ] = (syscall_handler_t *) wrap_sys_shmat, \
-	[ __NR_shmctl ] = (syscall_handler_t *) sys_shmctl, \
-	[ __NR_semop ] = (syscall_handler_t *) sys_semop, \
-	[ __NR_semget ] = (syscall_handler_t *) sys_semget, \
-	[ __NR_semctl ] = (syscall_handler_t *) sys_semctl, \
-	[ __NR_shmdt ] = (syscall_handler_t *) sys_shmdt, \
-	[ __NR_msgget ] = (syscall_handler_t *) sys_msgget, \
-	[ __NR_msgsnd ] = (syscall_handler_t *) sys_msgsnd, \
-	[ __NR_msgrcv ] = (syscall_handler_t *) sys_msgrcv, \
-	[ __NR_msgctl ] = (syscall_handler_t *) sys_msgctl, \
-	[ __NR_pivot_root ] = (syscall_handler_t *) sys_pivot_root, \
-	[ __NR_tuxcall ] = (syscall_handler_t *) sys_ni_syscall, \
-	[ __NR_security ] = (syscall_handler_t *) sys_ni_syscall, \
-	[ __NR_epoll_ctl_old ] = (syscall_handler_t *) sys_ni_syscall, \
-	[ __NR_epoll_wait_old ] = (syscall_handler_t *) sys_ni_syscall, \
-	[ __NR_modify_ldt ] = (syscall_handler_t *) sys_modify_ldt, \
-	[ __NR_arch_prctl ] = (syscall_handler_t *) sys_arch_prctl, \
-	[ __NR_socket ] = (syscall_handler_t *) sys_socket, \
-	[ __NR_connect ] = (syscall_handler_t *) sys_connect, \
-	[ __NR_accept ] = (syscall_handler_t *) sys_accept, \
-	[ __NR_recvfrom ] = (syscall_handler_t *) sys_recvfrom, \
-	[ __NR_recvmsg ] = (syscall_handler_t *) sys_recvmsg, \
-	[ __NR_sendmsg ] = (syscall_handler_t *) sys_sendmsg, \
-	[ __NR_bind ] = (syscall_handler_t *) sys_bind, \
-	[ __NR_listen ] = (syscall_handler_t *) sys_listen, \
-	[ __NR_getsockname ] = (syscall_handler_t *) sys_getsockname, \
-	[ __NR_getpeername ] = (syscall_handler_t *) sys_getpeername, \
-	[ __NR_socketpair ] = (syscall_handler_t *) sys_socketpair, \
-	[ __NR_sendto ] = (syscall_handler_t *) sys_sendto, \
-	[ __NR_shutdown ] = (syscall_handler_t *) sys_shutdown, \
-	[ __NR_setsockopt ] = (syscall_handler_t *) sys_setsockopt, \
-	[ __NR_getsockopt ] = (syscall_handler_t *) sys_getsockopt, \
-	[ __NR_iopl ] = (syscall_handler_t *) sys_ni_syscall, \
-	[ __NR_set_thread_area ] = (syscall_handler_t *) sys_ni_syscall, \
-	[ __NR_get_thread_area ] = (syscall_handler_t *) sys_ni_syscall, \
-	[ __NR_semtimedop ] = (syscall_handler_t *) sys_semtimedop, \
-	[ 251 ] = (syscall_handler_t *) sys_ni_syscall,
-
-#define LAST_ARCH_SYSCALL 251
-#define NR_syscalls 1024
+#define NR_syscalls (__NR_syscall_max + 1)
 
 #endif

arch/um/sys-x86_64/Makefile

@@ -6,7 +6,7 @@
 
 lib-y = bitops.o bugs.o csum-partial.o delay.o fault.o mem.o memcpy.o \
 	ptrace.o ptrace_user.o semaphore.o sigcontext.o signal.o \
-	syscalls.o sysrq.o thunk.o sys_call_table.o
+	syscalls.o sysrq.o thunk.o syscall_table.o
 
 USER_OBJS := ptrace_user.o sigcontext.o
 

arch/um/sys-x86_64/syscall_table.c

+/* System call table for UML/x86-64, copied from arch/x86_64/kernel/syscall.c
+ * with some changes for UML. */
+
+#include <linux/linkage.h>
+#include <linux/sys.h>
+#include <linux/cache.h>
+#include <linux/config.h>
+
+#define __NO_STUBS
+
+/* Below you can see, in terms of #define's, the differences between the x86-64
+ * and the UML syscall table. */
+
+/* Not going to be implemented by UML, since we have no hardware. */
+#define stub_iopl sys_ni_syscall
+#define sys_ioperm sys_ni_syscall
+
+/* The UML TLS problem. Note that x86_64 does not implement this, so the below
+ * is needed only for the ia32 compatibility. */
+/*#define sys_set_thread_area sys_ni_syscall
+#define sys_get_thread_area sys_ni_syscall*/
+
+/* For __NR_time. The x86-64 name hopefully will change from sys_time64 to
+ * sys_time (since the current situation is bogus). I've sent a patch to cleanup
+ * this. Remove below the obsoleted line. */
+#define sys_time64 um_time
+#define sys_time um_time
+
+/* On UML we call it this way ("old" means it's not mmap2) */
+#define sys_mmap old_mmap
+/* On x86-64 sys_uname is actually sys_newuname plus a compatibility trick.
+ * See arch/x86_64/kernel/sys_x86_64.c */
+#define sys_uname sys_uname64
+
+#define stub_clone sys_clone
+#define stub_fork sys_fork
+#define stub_vfork sys_vfork
+#define stub_execve sys_execve
+#define stub_rt_sigsuspend sys_rt_sigsuspend
+#define stub_sigaltstack sys_sigaltstack
+#define stub_rt_sigreturn sys_rt_sigreturn
+
+#define __SYSCALL(nr, sym) extern asmlinkage void sym(void) ;
+#undef _ASM_X86_64_UNISTD_H_
+#include <asm-x86_64/unistd.h>
+
+#undef __SYSCALL
+#define __SYSCALL(nr, sym) [ nr ] = sym,
+#undef _ASM_X86_64_UNISTD_H_
+
+typedef void (*sys_call_ptr_t)(void);
+
+extern void sys_ni_syscall(void);
+
+sys_call_ptr_t sys_call_table[__NR_syscall_max+1] __cacheline_aligned = {
+	/* Smells like a like a compiler bug -- it doesn't work when the & below is removed. */
+	[0 ... __NR_syscall_max] = &sys_ni_syscall,
+#include <asm-x86_64/unistd.h>
+};

arch/um/sys-x86_64/syscalls.c

@@ -14,6 +14,7 @@
 #include "asm/prctl.h" /* XXX This should get the constants from libc */
 #include "choose-mode.h"
 
+/* XXX: copied from x86-64: arch/x86_64/kernel/sys_x86_64.c */
 asmlinkage long wrap_sys_shmat(int shmid, char __user *shmaddr, int shmflg)
 {
 	unsigned long raddr;
@@ -21,6 +22,17 @@ asmlinkage long wrap_sys_shmat(int shmid, char __user *shmaddr, int shmflg)
 	return do_shmat(shmid, shmaddr, shmflg, &raddr) ?: (long) raddr;
 }
 
+asmlinkage long sys_uname64(struct new_utsname __user * name)
+{
+	int err;
+	down_read(&uts_sem);
+	err = copy_to_user(name, &system_utsname, sizeof (*name));
+	up_read(&uts_sem);
+	if (personality(current->personality) == PER_LINUX32)
+		err |= copy_to_user(&name->machine, "i686", 5);
+	return err ? -EFAULT : 0;
+}
+
 #ifdef CONFIG_MODE_TT
 extern int modify_ldt(int func, void *ptr, unsigned long bytecount);