Merge tag 'y2038-syscall-cleanup' of git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground into timers/2038

Pull preparatory work for y2038 changes from Arnd Bergmann:

System call unification and cleanup

The system call tables have diverged a bit over the years, and a number of
the recent additions never made it into all architectures, for one reason
or another.

This is an attempt to clean it up as far as we can without breaking
compatibility, doing a number of steps:

 - Add system calls that have not yet been integrated into all architectures
   but that we definitely want there. This includes {,f}statfs64() and
   get{eg,eu,g,p,u,pp}id() on alpha, which have been missing traditionally.

 - The s390 compat syscall handling is cleaned up to be more like what we
   do on other architectures, while keeping the 31-bit pointer
   extension. This was merged as a shared branch by the s390 maintainers
   and is included here in order to base the other patches on top.

 - Add the separate ipc syscalls on all architectures that traditionally
   only had sys_ipc(). This version is done without support for IPC_OLD
   that is we have in sys_ipc. The new semtimedop_time64 syscall will only
   be added here, not in sys_ipc

 - Add syscall numbers for a couple of syscalls that we probably don't need
   everywhere, in particular pkey_* and rseq, for the purpose of symmetry:
   if it's in asm-generic/unistd.h, it makes sense to have it everywhere. I
   expect that any future system calls will get assigned on all platforms
   together, even when they appear to be specific to a single architecture.

 - Prepare for having the same system call numbers for any future calls. In
   combination with the generated tables, this hopefully makes it easier to
   add new calls across all architectures together.

All of the above are technically separate from the y2038 work, but are done
as preparation before we add the new 64-bit time_t system calls everywhere,
providing a common baseline set of system calls.

I expect that glibc and other libraries that want to use 64-bit time_t will
require linux-5.1 kernel headers for building in the future, and at a much
later point may also require linux-5.1 or a later version as the minimum
kernel at runtime. Having a common baseline then allows the removal of many
architecture or kernel version specific workarounds.

1 files changed, 22 insertions, 10 deletions

diff --git a/ipc/syscall.c b/ipc/syscall.c
index 1ac06e3983c0..581bdff4e7c5 100644
--- a/ipc/syscall.c
+++ b/ipc/syscall.c
@@ -17,8 +17,8 @@
 #include <linux/shm.h>
 #include <linux/uaccess.h>
 
-SYSCALL_DEFINE6(ipc, unsigned int, call, int, first, unsigned long, second,
-		unsigned long, third, void __user *, ptr, long, fifth)
+int ksys_ipc(unsigned int call, int first, unsigned long second,
+	unsigned long third, void __user * ptr, long fifth)
 {
 	int version, ret;
 
@@ -47,7 +47,7 @@ SYSCALL_DEFINE6(ipc, unsigned int, call, int, first, unsigned long, second,
 			return -EINVAL;
 		if (get_user(arg, (unsigned long __user *) ptr))
 			return -EFAULT;
-		return ksys_semctl(first, second, third, arg);
+		return ksys_old_semctl(first, second, third, arg);
 	}
 
 	case MSGSND:
@@ -75,7 +75,7 @@ SYSCALL_DEFINE6(ipc, unsigned int, call, int, first, unsigned long, second,
 	case MSGGET:
 		return ksys_msgget((key_t) first, second);
 	case MSGCTL:
-		return ksys_msgctl(first, second,
+		return ksys_old_msgctl(first, second,
 				   (struct msqid_ds __user *)ptr);
 
 	case SHMAT:
@@ -100,12 +100,18 @@ SYSCALL_DEFINE6(ipc, unsigned int, call, int, first, unsigned long, second,
 	case SHMGET:
 		return ksys_shmget(first, second, third);
 	case SHMCTL:
-		return ksys_shmctl(first, second,
+		return ksys_old_shmctl(first, second,
 				   (struct shmid_ds __user *) ptr);
 	default:
 		return -ENOSYS;
 	}
 }
+
+SYSCALL_DEFINE6(ipc, unsigned int, call, int, first, unsigned long, second,
+		unsigned long, third, void __user *, ptr, long, fifth)
+{
+	return ksys_ipc(call, first, second, third, ptr, fifth);
+}
 #endif
 
 #ifdef CONFIG_COMPAT
@@ -121,8 +127,8 @@ struct compat_ipc_kludge {
 };
 
 #ifdef CONFIG_ARCH_WANT_OLD_COMPAT_IPC
-COMPAT_SYSCALL_DEFINE6(ipc, u32, call, int, first, int, second,
-	u32, third, compat_uptr_t, ptr, u32, fifth)
+int compat_ksys_ipc(u32 call, int first, int second,
+	u32 third, compat_uptr_t ptr, u32 fifth)
 {
 	int version;
 	u32 pad;
@@ -146,7 +152,7 @@ COMPAT_SYSCALL_DEFINE6(ipc, u32, call, int, first, int, second,
 			return -EINVAL;
 		if (get_user(pad, (u32 __user *) compat_ptr(ptr)))
 			return -EFAULT;
-		return compat_ksys_semctl(first, second, third, pad);
+		return compat_ksys_old_semctl(first, second, third, pad);
 
 	case MSGSND:
 		return compat_ksys_msgsnd(first, ptr, second, third);
@@ -171,7 +177,7 @@ COMPAT_SYSCALL_DEFINE6(ipc, u32, call, int, first, int, second,
 	case MSGGET:
 		return ksys_msgget(first, second);
 	case MSGCTL:
-		return compat_ksys_msgctl(first, second, compat_ptr(ptr));
+		return compat_ksys_old_msgctl(first, second, compat_ptr(ptr));
 
 	case SHMAT: {
 		int err;
@@ -190,10 +196,16 @@ COMPAT_SYSCALL_DEFINE6(ipc, u32, call, int, first, int, second,
 	case SHMGET:
 		return ksys_shmget(first, (unsigned int)second, third);
 	case SHMCTL:
-		return compat_ksys_shmctl(first, second, compat_ptr(ptr));
+		return compat_ksys_old_shmctl(first, second, compat_ptr(ptr));
 	}
 
 	return -ENOSYS;
 }
+
+COMPAT_SYSCALL_DEFINE6(ipc, u32, call, int, first, int, second,
+	u32, third, compat_uptr_t, ptr, u32, fifth)
+{
+	return compat_ksys_ipc(call, first, second, third, ptr, fifth);
+}
 #endif
 #endif