y2038: powerpc: Extend sysvipc data structures

powerpc, uses a nonstandard variation of the generic sysvipc
data structures, intended to have the padding moved around
so it can deal with big-endian 32-bit user space that has
64-bit time_t.

powerpc has the same definition as parisc and sparc, but now also
supports little-endian mode, which is now wrong because the
padding is made for big-endian user space.

This takes just take the same approach here that we have for
the asm-generic headers and adds separate 32-bit fields for the
upper halves of the timestamps, to let libc deal with the mess
in user space.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
diff --git a/arch/powerpc/include/asm/compat.h b/arch/powerpc/include/asm/compat.h
index b4773c8..85c8af2 100644
--- a/arch/powerpc/include/asm/compat.h
+++ b/arch/powerpc/include/asm/compat.h
@@ -162,10 +162,10 @@ struct compat_ipc64_perm {
 
 struct compat_semid64_ds {
 	struct compat_ipc64_perm sem_perm;
-	unsigned int __unused1;
-	compat_time_t sem_otime;
-	unsigned int __unused2;
-	compat_time_t sem_ctime;
+	unsigned int sem_otime_high;
+	unsigned int sem_otime;
+	unsigned int sem_ctime_high;
+	unsigned int sem_ctime;
 	compat_ulong_t sem_nsems;
 	compat_ulong_t __unused3;
 	compat_ulong_t __unused4;
@@ -173,12 +173,12 @@ struct compat_semid64_ds {
 
 struct compat_msqid64_ds {
 	struct compat_ipc64_perm msg_perm;
-	unsigned int __unused1;
-	compat_time_t msg_stime;
-	unsigned int __unused2;
-	compat_time_t msg_rtime;
-	unsigned int __unused3;
-	compat_time_t msg_ctime;
+	unsigned int msg_stime_high;
+	unsigned int msg_stime;
+	unsigned int msg_rtime_high;
+	unsigned int msg_rtime;
+	unsigned int msg_ctime_high;
+	unsigned int msg_ctime;
 	compat_ulong_t msg_cbytes;
 	compat_ulong_t msg_qnum;
 	compat_ulong_t msg_qbytes;
@@ -190,12 +190,12 @@ struct compat_msqid64_ds {
 
 struct compat_shmid64_ds {
 	struct compat_ipc64_perm shm_perm;
-	unsigned int __unused1;
-	compat_time_t shm_atime;
-	unsigned int __unused2;
-	compat_time_t shm_dtime;
-	unsigned int __unused3;
-	compat_time_t shm_ctime;
+	unsigned int shm_atime_high;
+	unsigned int shm_atime;
+	unsigned int shm_dtime_high;
+	unsigned int shm_dtime;
+	unsigned int shm_ctime_high;
+	unsigned int shm_ctime;
 	unsigned int __unused4;
 	compat_size_t shm_segsz;
 	compat_pid_t shm_cpid;