[S390] Introduce user_regset accessors for s390

Add the user_regset definitions for normal and compat processes, replace
the dump_regs core dump cruft with the generic CORE_DUMP_USER_REGSET and
replace binfmt_elf32.c with the generic compat_binfmt_elf.c implementation.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

arch/s390/Kconfig

@@ -146,6 +146,7 @@ config MATHEMU
 config COMPAT
 	bool "Kernel support for 31 bit emulation"
 	depends on 64BIT
+	select COMPAT_BINFMT_ELF
 	help
 	  Select this option if you want to enable your system kernel to
 	  handle system-calls from ELF binaries for 31 bit ESA.  This option

arch/s390/kernel/Makefile

@@ -7,6 +7,11 @@
 #
 CFLAGS_smp.o	:= -Wno-nonnull
 
+#
+# Pass UTS_MACHINE for user_regset definition
+#
+CFLAGS_ptrace.o		+= -DUTS_MACHINE='"$(UTS_MACHINE)"'
+
 obj-y	:=  bitmap.o traps.o time.o process.o base.o early.o \
             setup.o sys_s390.o ptrace.o signal.o cpcmd.o ebcdic.o \
 	    s390_ext.o debug.o irq.o ipl.o dis.o diag.o
@@ -23,7 +28,7 @@ obj-$(CONFIG_AUDIT)		+= audit.o
 compat-obj-$(CONFIG_AUDIT)	+= compat_audit.o
 obj-$(CONFIG_COMPAT)		+= compat_linux.o compat_signal.o \
 					compat_wrapper.o compat_exec_domain.o \
-					binfmt_elf32.o $(compat-obj-y)
+					$(compat-obj-y)
 
 obj-$(CONFIG_VIRT_TIMER)	+= vtime.o
 obj-$(CONFIG_STACKTRACE)	+= stacktrace.o

arch/s390/kernel/binfmt_elf32.c

-/*
- * Support for 32-bit Linux for S390 ELF binaries.
- *
- * Copyright (C) 2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
- * Author(s): Gerhard Tonn (ton@de.ibm.com)
- *
- * Heavily inspired by the 32-bit Sparc compat code which is
- * Copyright (C) 1995, 1996, 1997, 1998 David S. Miller (davem@redhat.com)
- * Copyright (C) 1995, 1996, 1997, 1998 Jakub Jelinek   (jj@ultra.linux.cz)
- */
-
-#define __ASMS390_ELF_H
-
-#include <linux/time.h>
-
-/*
- * These are used to set parameters in the core dumps.
- */
-#define ELF_CLASS	ELFCLASS32
-#define ELF_DATA	ELFDATA2MSB
-#define ELF_ARCH	EM_S390
-
-/*
- * This is used to ensure we don't load something for the wrong architecture.
- */
-#define elf_check_arch(x) \
-	(((x)->e_machine == EM_S390 || (x)->e_machine == EM_S390_OLD) \
-         && (x)->e_ident[EI_CLASS] == ELF_CLASS)
-
-/* ELF register definitions */
-#define NUM_GPRS      16
-#define NUM_FPRS      16
-#define NUM_ACRS      16    
-
-/* For SVR4/S390 the function pointer to be registered with `atexit` is
-   passed in R14. */
-#define ELF_PLAT_INIT(_r, load_addr) \
-	do { \
-		_r->gprs[14] = 0; \
-	} while(0)
-
-#define USE_ELF_CORE_DUMP
-#define ELF_EXEC_PAGESIZE       4096
-
-/* This is the location that an ET_DYN program is loaded if exec'ed.  Typical
-   use of this is to invoke "./ld.so someprog" to test out a new version of
-   the loader.  We need to make sure that it is out of the way of the program
-   that it will "exec", and that there is sufficient room for the brk.  */
-
-#define ELF_ET_DYN_BASE         (TASK_SIZE / 3 * 2)
-
-/* Wow, the "main" arch needs arch dependent functions too.. :) */
-
-/* regs is struct pt_regs, pr_reg is elf_gregset_t (which is
-   now struct_user_regs, they are different) */
-
-#define ELF_CORE_COPY_REGS(pr_reg, regs) dump_regs32(regs, &pr_reg);
-
-#define ELF_CORE_COPY_TASK_REGS(tsk, regs) dump_task_regs32(tsk, regs)
-
-#define ELF_CORE_COPY_FPREGS(tsk, fpregs) dump_task_fpu(tsk, fpregs)
-
-/* This yields a mask that user programs can use to figure out what
-   instruction set this CPU supports. */
-
-#define ELF_HWCAP (0)
-
-/* This yields a string that ld.so will use to load implementation
-   specific libraries for optimization.  This is more specific in
-   intent than poking at uname or /proc/cpuinfo.
-
-   For the moment, we have only optimizations for the Intel generations,
-   but that could change... */
-
-#define ELF_PLATFORM (NULL)
-
-#define SET_PERSONALITY(ex, ibcs2)			\
-do {							\
-	if (ibcs2)                                      \
-		set_personality(PER_SVR4);              \
-	else if (current->personality != PER_LINUX32)   \
-		set_personality(PER_LINUX);             \
-	set_thread_flag(TIF_31BIT);			\
-} while (0)
-
-#include "compat_linux.h"
-
-typedef _s390_fp_regs32 elf_fpregset_t;
-
-typedef struct
-{
-	
-	_psw_t32	psw;
-	__u32		gprs[__NUM_GPRS]; 
-	__u32		acrs[__NUM_ACRS]; 
-	__u32		orig_gpr2;
-} s390_regs32;
-typedef s390_regs32 elf_gregset_t;
-
-static inline int dump_regs32(struct pt_regs *ptregs, elf_gregset_t *regs)
-{
-	int i;
-
-	memcpy(&regs->psw.mask, &ptregs->psw.mask, 4);
-	memcpy(&regs->psw.addr, (char *)&ptregs->psw.addr + 4, 4);
-	for (i = 0; i < NUM_GPRS; i++)
-		regs->gprs[i] = ptregs->gprs[i];
-	save_access_regs(regs->acrs);
-	regs->orig_gpr2 = ptregs->orig_gpr2;
-	return 1;
-}
-
-static inline int dump_task_regs32(struct task_struct *tsk, elf_gregset_t *regs)
-{
-	struct pt_regs *ptregs = task_pt_regs(tsk);
-	int i;
-
-	memcpy(&regs->psw.mask, &ptregs->psw.mask, 4);
-	memcpy(&regs->psw.addr, (char *)&ptregs->psw.addr + 4, 4);
-	for (i = 0; i < NUM_GPRS; i++)
-		regs->gprs[i] = ptregs->gprs[i];
-	memcpy(regs->acrs, tsk->thread.acrs, sizeof(regs->acrs));
-	regs->orig_gpr2 = ptregs->orig_gpr2;
-	return 1;
-}
-
-static inline int dump_task_fpu(struct task_struct *tsk, elf_fpregset_t *fpregs)
-{
-	if (tsk == current)
-		save_fp_regs((s390_fp_regs *) fpregs);
-	else
-		memcpy(fpregs, &tsk->thread.fp_regs, sizeof(elf_fpregset_t));
-	return 1;
-}
-
-#include <asm/processor.h>
-#include <asm/pgalloc.h>
-#include <linux/module.h>
-#include <linux/elfcore.h>
-#include <linux/binfmts.h>
-#include <linux/compat.h>
-
-#define elf_prstatus elf_prstatus32
-struct elf_prstatus32
-{
-	struct elf_siginfo pr_info;	/* Info associated with signal */
-	short	pr_cursig;		/* Current signal */
-	u32	pr_sigpend;	/* Set of pending signals */
-	u32	pr_sighold;	/* Set of held signals */
-	pid_t	pr_pid;
-	pid_t	pr_ppid;
-	pid_t	pr_pgrp;
-	pid_t	pr_sid;
-	struct compat_timeval pr_utime;	/* User time */
-	struct compat_timeval pr_stime;	/* System time */
-	struct compat_timeval pr_cutime;	/* Cumulative user time */
-	struct compat_timeval pr_cstime;	/* Cumulative system time */
-	elf_gregset_t pr_reg;	/* GP registers */
-	int pr_fpvalid;		/* True if math co-processor being used.  */
-};
-
-#define elf_prpsinfo elf_prpsinfo32
-struct elf_prpsinfo32
-{
-	char	pr_state;	/* numeric process state */
-	char	pr_sname;	/* char for pr_state */
-	char	pr_zomb;	/* zombie */
-	char	pr_nice;	/* nice val */
-	u32	pr_flag;	/* flags */
-	u16	pr_uid;
-	u16	pr_gid;
-	pid_t	pr_pid, pr_ppid, pr_pgrp, pr_sid;
-	/* Lots missing */
-	char	pr_fname[16];	/* filename of executable */
-	char	pr_psargs[ELF_PRARGSZ];	/* initial part of arg list */
-};
-
-#include <linux/highuid.h>
-
-/*
-#define init_elf_binfmt init_elf32_binfmt
-*/
-
-#undef start_thread
-#define start_thread                    start_thread31 
-
-static inline void start_thread31(struct pt_regs *regs, unsigned long new_psw,
-				  unsigned long new_stackp)
-{
-	set_fs(USER_DS);
-	regs->psw.mask	= psw_user32_bits;
-	regs->psw.addr	= new_psw;
-	regs->gprs[15]	= new_stackp;
-	crst_table_downgrade(current->mm, 1UL << 31);
-}
-
-MODULE_DESCRIPTION("Binary format loader for compatibility with 32bit Linux for S390 binaries,"
-                   " Copyright 2000 IBM Corporation"); 
-MODULE_AUTHOR("Gerhard Tonn <ton@de.ibm.com>");
-
-#undef MODULE_DESCRIPTION
-#undef MODULE_AUTHOR
-
-#undef cputime_to_timeval
-#define cputime_to_timeval cputime_to_compat_timeval
-static inline void
-cputime_to_compat_timeval(const cputime_t cputime, struct compat_timeval *value)
-{
-	value->tv_usec = cputime % 1000000;
-	value->tv_sec = cputime / 1000000;
-}
-
-#include "../../../fs/binfmt_elf.c"
-

arch/s390/kernel/compat_ptrace.h

 #ifndef _PTRACE32_H
 #define _PTRACE32_H
 
-#include "compat_linux.h"  /* needed for _psw_t32 */
+#include "compat_linux.h"  /* needed for psw_compat_t */
 
 typedef struct {
 	__u32 cr[3];
@@ -38,7 +38,7 @@ typedef struct {
 
 struct user_regs_struct32
 {
-	_psw_t32 psw;
+	psw_compat_t psw;
 	u32 gprs[NUM_GPRS];
 	u32 acrs[NUM_ACRS];
 	u32 orig_gpr2;

include/asm-s390/elf.h

@@ -113,6 +113,9 @@
 typedef s390_fp_regs elf_fpregset_t;
 typedef s390_regs elf_gregset_t;
 
+typedef s390_fp_regs compat_elf_fpregset_t;
+typedef s390_compat_regs compat_elf_gregset_t;
+
 #include <linux/sched.h>	/* for task_struct */
 #include <asm/system.h>		/* for save_access_regs */
 #include <asm/mmu_context.h>
@@ -123,6 +126,10 @@ typedef s390_regs elf_gregset_t;
 #define elf_check_arch(x) \
 	(((x)->e_machine == EM_S390 || (x)->e_machine == EM_S390_OLD) \
          && (x)->e_ident[EI_CLASS] == ELF_CLASS) 
+#define compat_elf_check_arch(x) \
+	(((x)->e_machine == EM_S390 || (x)->e_machine == EM_S390_OLD) \
+	 && (x)->e_ident[EI_CLASS] == ELF_CLASS)
+#define compat_start_thread	start_thread31
 
 /* For SVR4/S390 the function pointer to be registered with `atexit` is
    passed in R14. */
@@ -131,6 +138,7 @@ typedef s390_regs elf_gregset_t;
 		_r->gprs[14] = 0; \
 	} while (0)
 
+#define CORE_DUMP_USE_REGSET
 #define USE_ELF_CORE_DUMP
 #define ELF_EXEC_PAGESIZE	4096
 
@@ -140,44 +148,6 @@ typedef s390_regs elf_gregset_t;
    that it will "exec", and that there is sufficient room for the brk.  */
 #define ELF_ET_DYN_BASE		(STACK_TOP / 3 * 2)
 
-/* Wow, the "main" arch needs arch dependent functions too.. :) */
-
-/* regs is struct pt_regs, pr_reg is elf_gregset_t (which is
-   now struct_user_regs, they are different) */
-
-static inline int dump_regs(struct pt_regs *ptregs, elf_gregset_t *regs)
-{
-	memcpy(&regs->psw, &ptregs->psw, sizeof(regs->psw)+sizeof(regs->gprs));
-	save_access_regs(regs->acrs);
-	regs->orig_gpr2 = ptregs->orig_gpr2;
-	return 1;
-}
-
-#define ELF_CORE_COPY_REGS(pr_reg, regs) dump_regs(regs, &pr_reg);
-
-static inline int dump_task_regs(struct task_struct *tsk, elf_gregset_t *regs)
-{
-	struct pt_regs *ptregs = task_pt_regs(tsk);
-	memcpy(&regs->psw, &ptregs->psw, sizeof(regs->psw)+sizeof(regs->gprs));
-	memcpy(regs->acrs, tsk->thread.acrs, sizeof(regs->acrs));
-	regs->orig_gpr2 = ptregs->orig_gpr2;
-	return 1;
-}
-
-#define ELF_CORE_COPY_TASK_REGS(tsk, regs) dump_task_regs(tsk, regs)
-
-static inline int dump_task_fpu(struct task_struct *tsk, elf_fpregset_t *fpregs)
-{
-	if (tsk == current)
-		save_fp_regs(fpregs);
-	else
-		memcpy(fpregs, &tsk->thread.fp_regs, sizeof(elf_fpregset_t));
-	return 1;
-}
-
-#define ELF_CORE_COPY_FPREGS(tsk, fpregs) dump_task_fpu(tsk, fpregs)
-
-
 /* This yields a mask that user programs can use to figure out what
    instruction set this CPU supports. */
 
@@ -204,7 +174,10 @@ do {							\
 		set_personality(PER_SVR4);		\
 	else if (current->personality != PER_LINUX32)	\
 		set_personality(PER_LINUX);		\
-	clear_thread_flag(TIF_31BIT);			\
+	if ((ex).e_ident[EI_CLASS] == ELFCLASS32)	\
+		set_thread_flag(TIF_31BIT);		\
+	else						\
+		clear_thread_flag(TIF_31BIT);		\
 } while (0)
 #endif /* __s390x__ */
 

include/asm-s390/processor.h

@@ -143,11 +143,19 @@ struct stack_frame {
 /*
  * Do necessary setup to start up a new thread.
  */
-#define start_thread(regs, new_psw, new_stackp) do {            \
+#define start_thread(regs, new_psw, new_stackp) do {		\
 	set_fs(USER_DS);					\
 	regs->psw.mask	= psw_user_bits;			\
-        regs->psw.addr  = new_psw | PSW_ADDR_AMODE;             \
-        regs->gprs[15]  = new_stackp ;                          \
+	regs->psw.addr	= new_psw | PSW_ADDR_AMODE;		\
+	regs->gprs[15]	= new_stackp;				\
+} while (0)
+
+#define start_thread31(regs, new_psw, new_stackp) do {		\
+	set_fs(USER_DS);					\
+	regs->psw.mask	= psw_user32_bits;			\
+	regs->psw.addr	= new_psw | PSW_ADDR_AMODE;		\
+	regs->gprs[15]	= new_stackp;				\
+	crst_table_downgrade(current->mm, 1UL << 31);		\
 } while (0)
 
 /* Forward declaration, a strange C thing */

include/asm-s390/ptrace.h

@@ -215,6 +215,12 @@ typedef struct
         unsigned long addr;
 } __attribute__ ((aligned(8))) psw_t;
 
+typedef struct
+{
+	__u32	mask;
+	__u32	addr;
+} __attribute__ ((aligned(8))) psw_compat_t;
+
 #ifndef __s390x__
 
 #define PSW_MASK_PER		0x40000000UL
@@ -292,6 +298,15 @@ typedef struct
 	unsigned long orig_gpr2;
 } s390_regs;
 
+typedef struct
+{
+	psw_compat_t	psw;
+	__u32		gprs[NUM_GPRS];
+	__u32		acrs[NUM_ACRS];
+	__u32		orig_gpr2;
+} s390_compat_regs;
+
+
 #ifdef __KERNEL__
 #include <asm/setup.h>
 #include <asm/page.h>