sh: ptrace: Introduce user_regset interface for gp regs.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

3 files changed, 115 insertions, 18 deletions

diff --git a/arch/sh/include/asm/elf.h b/arch/sh/include/asm/elf.h
index f01449a8d378..455d9e1e1438 100644
--- a/arch/sh/include/asm/elf.h
+++ b/arch/sh/include/asm/elf.h
@@ -108,6 +108,15 @@ typedef struct user_fpu_struct elf_fpregset_t;
 #define elf_check_fdpic(x)		((x)->e_flags & EF_SH_FDPIC)
 #define elf_check_const_displacement(x)	((x)->e_flags & EF_SH_PIC)
 
+#if defined(CONFIG_SUPERH32) && \
+	(!defined(CONFIG_SH_FPU) && !defined(CONFIG_SH_DSP))
+/*
+ * Enable dump using regset for general purpose registers, use this as
+ * the default once the FPU and DSP registers are moved over also.
+ */
+#define CORE_DUMP_USE_REGSET
+#endif
+
 #define USE_ELF_CORE_DUMP
 #define ELF_FDPIC_CORE_EFLAGS	EF_SH_FDPIC
 #define ELF_EXEC_PAGESIZE	PAGE_SIZE
diff --git a/arch/sh/include/asm/ptrace.h b/arch/sh/include/asm/ptrace.h
index b86aeabba61a..bf73646e2d2b 100644
--- a/arch/sh/include/asm/ptrace.h
+++ b/arch/sh/include/asm/ptrace.h
@@ -87,12 +87,18 @@ struct pt_dspregs {
 	unsigned long	mod;
 };
 
+#define PTRACE_GETREGS		12	/* General registers */
+#define PTRACE_SETREGS		13
+
+#define PTRACE_GETFPREGS	14	/* FPU registers */
+#define PTRACE_SETFPREGS	15
+
 #define PTRACE_GETFDPIC		31	/* get the ELF fdpic loadmap address */
 
 #define PTRACE_GETFDPIC_EXEC	0	/* [addr] request the executable loadmap */
 #define PTRACE_GETFDPIC_INTERP	1	/* [addr] request the interpreter loadmap */
 
-#define	PTRACE_GETDSPREGS	55
+#define	PTRACE_GETDSPREGS	55	/* DSP registers */
 #define	PTRACE_SETDSPREGS	56
 #endif
 
diff --git a/arch/sh/kernel/ptrace_32.c b/arch/sh/kernel/ptrace_32.c
index 84bf3420597c..5e3ba10255cd 100644
--- a/arch/sh/kernel/ptrace_32.c
+++ b/arch/sh/kernel/ptrace_32.c
@@ -1,12 +1,14 @@
 /*
- * linux/arch/sh/kernel/ptrace.c
+ * SuperH process tracing
  *
- * Original x86 implementation:
- *	By Ross Biro 1/23/92
- *	edited by Linus Torvalds
+ * Copyright (C) 1999, 2000  Kaz Kojima & Niibe Yutaka
+ * Copyright (C) 2002 - 2008  Paul Mundt
  *
- * SuperH version:   Copyright (C) 1999, 2000  Kaz Kojima & Niibe Yutaka
- * Audit support: Yuichi Nakamura <ynakam@hitachisoft.jp>
+ * Audit support by Yuichi Nakamura <ynakam@hitachisoft.jp>
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
  */
 #include <linux/kernel.h>
 #include <linux/sched.h>
@@ -22,6 +24,8 @@
 #include <linux/audit.h>
 #include <linux/seccomp.h>
 #include <linux/tracehook.h>
+#include <linux/elf.h>
+#include <linux/regset.h>
 #include <asm/uaccess.h>
 #include <asm/pgtable.h>
 #include <asm/system.h>
@@ -30,11 +34,6 @@
 #include <asm/syscalls.h>
 
 /*
- * does not yet catch signals sent when the child dies.
- * in exit.c or in signal.c.
- */
-
-/*
  * This routine will get a word off of the process kernel stack.
  */
 static inline int get_stack_long(struct task_struct *task, int offset)
@@ -62,16 +61,12 @@ static inline int put_stack_long(struct task_struct *task, int offset,
 
 void user_enable_single_step(struct task_struct *child)
 {
-	struct pt_regs *regs = task_pt_regs(child);
-	long pc;
-
-	pc = get_stack_long(child, (long)&regs->pc);
-
 	/* Next scheduling will set up UBC */
 	if (child->thread.ubc_pc == 0)
 		ubc_usercnt += 1;
 
-	child->thread.ubc_pc = pc;
+	child->thread.ubc_pc = get_stack_long(child,
+				offsetof(struct pt_regs, pc));
 
 	set_tsk_thread_flag(child, TIF_SINGLESTEP);
 }
@@ -103,6 +98,83 @@ void ptrace_disable(struct task_struct *child)
 	user_disable_single_step(child);
 }
 
+static int genregs_get(struct task_struct *target,
+		       const struct user_regset *regset,
+		       unsigned int pos, unsigned int count,
+		       void *kbuf, void __user *ubuf)
+{
+	const struct pt_regs *regs = task_pt_regs(target);
+	int ret;
+
+	ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
+				  regs->regs,
+				  0, 16 * sizeof(unsigned long));
+	if (!ret)
+		/* PC, PR, SR, GBR, MACH, MACL, TRA */
+		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
+					  &regs->pc,
+					  offsetof(struct pt_regs, pc),
+					  sizeof(struct pt_regs));
+	if (!ret)
+		ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
+					       sizeof(struct pt_regs), -1);
+
+	return ret;
+}
+
+static int genregs_set(struct task_struct *target,
+		       const struct user_regset *regset,
+		       unsigned int pos, unsigned int count,
+		       const void *kbuf, const void __user *ubuf)
+{
+	struct pt_regs *regs = task_pt_regs(target);
+	int ret;
+
+	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+				 regs->regs,
+				 0, 16 * sizeof(unsigned long));
+	if (!ret && count > 0)
+		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+					 &regs->pc,
+					 offsetof(struct pt_regs, pc),
+					 sizeof(struct pt_regs));
+	if (!ret)
+		ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
+						sizeof(struct pt_regs), -1);
+
+	return ret;
+}
+
+/*
+ * These are our native regset flavours.
+ */
+enum sh_regset {
+	REGSET_GENERAL,
+};
+
+static const struct user_regset sh_regsets[] = {
+	/*
+	 * Format is:
+	 *	R0 --> R15
+	 *	PC, PR, SR, GBR, MACH, MACL, TRA
+	 */
+	[REGSET_GENERAL] = {
+		.core_note_type	= NT_PRSTATUS,
+		.n		= ELF_NGREG,
+		.size		= sizeof(long),
+		.align		= sizeof(long),
+		.get		= genregs_get,
+		.set		= genregs_set,
+	},
+};
+
+static const struct user_regset_view user_sh_native_view = {
+	.name		= "sh",
+	.e_machine	= EM_SH,
+	.regsets	= sh_regsets,
+	.n		= ARRAY_SIZE(sh_regsets),
+};
+
 long arch_ptrace(struct task_struct *child, long request, long addr, long data)
 {
 	struct user * dummy = NULL;
@@ -159,6 +231,16 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
 		}
 		break;
 
+	case PTRACE_GETREGS:
+		return copy_regset_to_user(child, &user_sh_native_view,
+					   REGSET_GENERAL,
+					   0, sizeof(struct pt_regs),
+					   (void __user *)data);
+	case PTRACE_SETREGS:
+		return copy_regset_from_user(child, &user_sh_native_view,
+					     REGSET_GENERAL,
+					     0, sizeof(struct pt_regs),
+					     (const void __user *)data);
 #ifdef CONFIG_SH_DSP
 	case PTRACE_GETDSPREGS: {
 		unsigned long dp;