y2038: parisc: Extend sysvipc data structures

parisc, 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.

Unlike most architectures, parisc actually succeeded in
defining this right for big-endian CPUs, but as everyone else
got it wrong, we just use the same hack everywhere.

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>

1 files changed, 8 insertions, 11 deletions

diff --git a/arch/parisc/include/uapi/asm/shmbuf.h b/arch/parisc/include/uapi/asm/shmbuf.h
index cd4dbce55d0b..c89b3dd8db21 100644
--- a/arch/parisc/include/uapi/asm/shmbuf.h
+++ b/arch/parisc/include/uapi/asm/shmbuf.h
@@ -10,25 +10,22 @@
  * between kernel and user space.
  *
  * Pad space is left for:
- * - 64-bit time_t to solve y2038 problem
  * - 2 miscellaneous 32-bit values
  */
 
 struct shmid64_ds {
 	struct ipc64_perm	shm_perm;	/* operation perms */
-#if __BITS_PER_LONG != 64
-	unsigned int		__pad1;
-#endif
+#if __BITS_PER_LONG == 64
 	__kernel_time_t		shm_atime;	/* last attach time */
-#if __BITS_PER_LONG != 64
-	unsigned int		__pad2;
-#endif
 	__kernel_time_t		shm_dtime;	/* last detach time */
-#if __BITS_PER_LONG != 64
-	unsigned int		__pad3;
-#endif
 	__kernel_time_t		shm_ctime;	/* last change time */
-#if __BITS_PER_LONG != 64
+#else
+	unsigned long		shm_atime_high;
+	unsigned long		shm_atime;	/* last attach time */
+	unsigned long		shm_dtime_high;
+	unsigned long		shm_dtime;	/* last detach time */
+	unsigned long		shm_ctime_high;
+	unsigned long		shm_ctime;	/* last change time */
 	unsigned int		__pad4;
 #endif
 	__kernel_size_t		shm_segsz;	/* size of segment (bytes) */