improve sys_newuname() for compat architectures

On an architecture that supports 32-bit compat we need to override the
reported machine in uname with the 32-bit value.  Instead of doing this
separately in every architecture introduce a COMPAT_UTS_MACHINE define in
<asm/compat.h> and apply it directly in sys_newuname().

Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: James Morris <jmorris@namei.org>
Cc: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

4 files changed, 3 insertions, 17 deletions

diff --git a/arch/powerpc/include/asm/compat.h b/arch/powerpc/include/asm/compat.h
index 4774c2f92232..396d21a80058 100644
--- a/arch/powerpc/include/asm/compat.h
+++ b/arch/powerpc/include/asm/compat.h
@@ -7,7 +7,8 @@
 #include <linux/types.h>
 #include <linux/sched.h>
 
-#define COMPAT_USER_HZ	100
+#define COMPAT_USER_HZ		100
+#define COMPAT_UTS_MACHINE	"ppc\0\0"
 
 typedef u32		compat_size_t;
 typedef s32		compat_ssize_t;
diff --git a/arch/powerpc/include/asm/syscalls.h b/arch/powerpc/include/asm/syscalls.h
index 23bb74e7f946..4084e567d28e 100644
--- a/arch/powerpc/include/asm/syscalls.h
+++ b/arch/powerpc/include/asm/syscalls.h
@@ -7,7 +7,6 @@
 #include <linux/types.h>
 #include <asm/signal.h>
 
-struct new_utsname;
 struct pt_regs;
 struct rtas_args;
 struct sigaction;
@@ -38,7 +37,6 @@ asmlinkage long sys_rt_sigaction(int sig,
 asmlinkage long ppc64_personality(unsigned long personality);
 asmlinkage int ppc_rtas(struct rtas_args __user *uargs);
 asmlinkage time_t sys64_time(time_t __user * tloc);
-asmlinkage long ppc_newuname(struct new_utsname __user * name);
 
 asmlinkage long sys_rt_sigsuspend(sigset_t __user *unewset,
 		size_t sigsetsize);
diff --git a/arch/powerpc/include/asm/systbl.h b/arch/powerpc/include/asm/systbl.h
index 07d2d19ab5e9..a5ee345b6a5c 100644
--- a/arch/powerpc/include/asm/systbl.h
+++ b/arch/powerpc/include/asm/systbl.h
@@ -125,7 +125,7 @@ SYSCALL_SPU(fsync)
 SYS32ONLY(sigreturn)
 PPC_SYS(clone)
 COMPAT_SYS_SPU(setdomainname)
-PPC_SYS_SPU(newuname)
+SYSCALL_SPU(newuname)
 SYSCALL(ni_syscall)
 COMPAT_SYS_SPU(adjtimex)
 SYSCALL_SPU(mprotect)
diff --git a/arch/powerpc/kernel/syscalls.c b/arch/powerpc/kernel/syscalls.c
index 5251221e7a5a..69d3c5d50a54 100644
--- a/arch/powerpc/kernel/syscalls.c
+++ b/arch/powerpc/kernel/syscalls.c
@@ -132,19 +132,6 @@ static inline int override_machine(char __user *mach)
 	return 0;
 }
 
-long ppc_newuname(struct new_utsname __user * name)
-{
-	int err = 0;
-
-	down_read(&uts_sem);
-	if (copy_to_user(name, utsname(), sizeof(*name)))
-		err = -EFAULT;
-	up_read(&uts_sem);
-	if (!err)
-		err = override_machine(name->machine);
-	return err;
-}
-
 int sys_uname(struct old_utsname __user *name)
 {
 	int err = 0;