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

Pull 'y2038: IPC system call conversion' from Arnd Bergmann:

"This is a follow-up to Deepa's work on the timekeeping system calls,
 providing a y2038-safe syscall API for SYSVIPC. It uses a combination
 of two strategies:

 For sys_msgctl, sys_semctl and sys_shmctl, I do not introduce a completely
 new set of replacement system calls, but instead extend the existing
 ones to return data in the reserved fields of the normal data structure.

 This should be completely transparent to any existing user space, and
 only after the 32-bit time_t wraps, it will make a difference in the
 returned data.

 libc implementations will consequently have to provide their own data
 structures when they move to 64-bit time_t, and convert the structures
 in user space from the ones returned by the kernel.

 In contrast, mq_timedsend, mq_timedreceive and and semtimedop all do
 need to change because having a libc redefine the timespec type
 breaks the ABI, so with this series there will be two separate entry
 points for 32-bit architectures.

 There are three cases here:

 - little-endian architectures (except powerpc and mips) can use
   the normal layout and just cast the data structure to the user space
   type that contains 64-bit numbers.

 - parisc and sparc can do the same thing with big-endian user space

 - little-endian powerpc and most big-endian architectures have
   to flip the upper and lower 32-bit halves of the time_t value in memory,
   but can otherwise keep using the normal layout

 - mips and big-endian xtensa need to be more careful because
   they are not consistent in their definitions, and they have to provide
   custom libc implementations for the system calls to use 64-bit time_t."

4 files changed, 3 insertions, 117 deletions

diff --git a/arch/s390/include/uapi/asm/Kbuild b/arch/s390/include/uapi/asm/Kbuild
index faef3f7e8353..e364873e0d10 100644
--- a/arch/s390/include/uapi/asm/Kbuild
+++ b/arch/s390/include/uapi/asm/Kbuild
@@ -9,9 +9,12 @@ generic-y += errno.h
 generic-y += fcntl.h
 generic-y += ioctl.h
 generic-y += mman.h
+generic-y += msgbuf.h
 generic-y += param.h
 generic-y += poll.h
 generic-y += resource.h
+generic-y += sembuf.h
+generic-y += shmbuf.h
 generic-y += sockios.h
 generic-y += swab.h
 generic-y += termbits.h
diff --git a/arch/s390/include/uapi/asm/msgbuf.h b/arch/s390/include/uapi/asm/msgbuf.h
deleted file mode 100644
index 604f847cd68c..000000000000
--- a/arch/s390/include/uapi/asm/msgbuf.h
+++ /dev/null
@@ -1,38 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
-#ifndef _S390_MSGBUF_H
-#define _S390_MSGBUF_H
-
-/* 
- * The msqid64_ds structure for S/390 architecture.
- * Note extra padding because this structure is passed back and forth
- * between kernel and user space.
- *
- * Pad space is left for:
- * - 64-bit time_t to solve y2038 problem
- * - 2 miscellaneous 32-bit values
- */
-
-struct msqid64_ds {
-	struct ipc64_perm msg_perm;
-	__kernel_time_t msg_stime;	/* last msgsnd time */
-#ifndef __s390x__
-	unsigned long	__unused1;
-#endif /* ! __s390x__ */
-	__kernel_time_t msg_rtime;	/* last msgrcv time */
-#ifndef __s390x__
-	unsigned long	__unused2;
-#endif /* ! __s390x__ */
-	__kernel_time_t msg_ctime;	/* last change time */
-#ifndef __s390x__
-	unsigned long	__unused3;
-#endif /* ! __s390x__ */
-	unsigned long  msg_cbytes;	/* current number of bytes on queue */
-	unsigned long  msg_qnum;	/* number of messages in queue */
-	unsigned long  msg_qbytes;	/* max number of bytes on queue */
-	__kernel_pid_t msg_lspid;	/* pid of last msgsnd */
-	__kernel_pid_t msg_lrpid;	/* last receive pid */
-	unsigned long  __unused4;
-	unsigned long  __unused5;
-};
-
-#endif /* _S390_MSGBUF_H */
diff --git a/arch/s390/include/uapi/asm/sembuf.h b/arch/s390/include/uapi/asm/sembuf.h
deleted file mode 100644
index 3e917697b668..000000000000
--- a/arch/s390/include/uapi/asm/sembuf.h
+++ /dev/null
@@ -1,30 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
-#ifndef _S390_SEMBUF_H
-#define _S390_SEMBUF_H
-
-/* 
- * The semid64_ds structure for S/390 architecture.
- * Note extra padding because this structure is passed back and forth
- * between kernel and user space.
- *
- * Pad space is left for:
- * - 64-bit time_t to solve y2038 problem (for !__s390x__)
- * - 2 miscellaneous 32-bit values
- */
-
-struct semid64_ds {
-	struct ipc64_perm sem_perm;		/* permissions .. see ipc.h */
-	__kernel_time_t	sem_otime;		/* last semop time */
-#ifndef __s390x__
-	unsigned long	__unused1;
-#endif /* ! __s390x__ */
-	__kernel_time_t	sem_ctime;		/* last change time */
-#ifndef __s390x__
-	unsigned long	__unused2;
-#endif /* ! __s390x__ */
-	unsigned long	sem_nsems;		/* no. of semaphores in array */
-	unsigned long	__unused3;
-	unsigned long	__unused4;
-};
-
-#endif /* _S390_SEMBUF_H */
diff --git a/arch/s390/include/uapi/asm/shmbuf.h b/arch/s390/include/uapi/asm/shmbuf.h
deleted file mode 100644
index 9cdce8d7ce60..000000000000
--- a/arch/s390/include/uapi/asm/shmbuf.h
+++ /dev/null
@@ -1,49 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
-#ifndef _S390_SHMBUF_H
-#define _S390_SHMBUF_H
-
-/* 
- * The shmid64_ds structure for S/390 architecture.
- * Note extra padding because this structure is passed back and forth
- * between kernel and user space.
- *
- * Pad space is left for:
- * - 64-bit time_t to solve y2038 problem (for !__s390x__)
- * - 2 miscellaneous 32-bit values
- */
-
-struct shmid64_ds {
-	struct ipc64_perm	shm_perm;	/* operation perms */
-	size_t			shm_segsz;	/* size of segment (bytes) */
-	__kernel_time_t		shm_atime;	/* last attach time */
-#ifndef __s390x__
-	unsigned long		__unused1;
-#endif /* ! __s390x__ */
-	__kernel_time_t		shm_dtime;	/* last detach time */
-#ifndef __s390x__
-	unsigned long		__unused2;
-#endif /* ! __s390x__ */
-	__kernel_time_t		shm_ctime;	/* last change time */
-#ifndef __s390x__
-	unsigned long		__unused3;
-#endif /* ! __s390x__ */
-	__kernel_pid_t		shm_cpid;	/* pid of creator */
-	__kernel_pid_t		shm_lpid;	/* pid of last operator */
-	unsigned long		shm_nattch;	/* no. of current attaches */
-	unsigned long		__unused4;
-	unsigned long		__unused5;
-};
-
-struct shminfo64 {
-	unsigned long	shmmax;
-	unsigned long	shmmin;
-	unsigned long	shmmni;
-	unsigned long	shmseg;
-	unsigned long	shmall;
-	unsigned long	__unused1;
-	unsigned long	__unused2;
-	unsigned long	__unused3;
-	unsigned long	__unused4;
-};
-
-#endif /* _S390_SHMBUF_H */