From a00648aa2b38936a5052cee8e2f94691f085301a Mon Sep 17 00:00:00 2001
From: Andreas Schwab <schwab@linux-m68k.org>
Date: Sat, 12 Nov 2016 20:02:23 +0100
Subject: [PATCH] m68k: switch to PTRACE_GETREGS

* Makefile.am (EXTRA_DIST): Add linux/m68k/arch_regs.h, remove
linux/m68k/get_syscall_result.c.
* linux/m68k/arch_regs.c (m68k_d0, ARCH_PC_PEEK_ADDR): Don't
define.
(m68k_regs, m68k_usp_ptr, ARCH_PC_REG, ARCH_REGS_FOR_GETREGS):
Define.
* linux/m68k/arch_regs.h: New file.
* linux/m68k/arch_sigreturn.c (arch_sigreturn): Use m68k_usp_ptr.
* linux/m68k/get_error.c (get_error): Use m68k_regs.d0.
* linux/m68k/get_scno.c (arch_get_scno): Use m68k_regs.orig_d0.
* linux/m68k/get_syscall_args.c (get_syscall_args): Use m68k_regs.
* linux/m68k/get_syscall_result.c: Remove.
---
 Makefile.am                     |  2 +-
 linux/m68k/arch_regs.c          |  6 ++++--
 linux/m68k/arch_regs.h          |  1 +
 linux/m68k/arch_sigreturn.c     |  4 +---
 linux/m68k/get_error.c          |  6 +++---
 linux/m68k/get_scno.c           |  3 ++-
 linux/m68k/get_syscall_args.c   | 11 ++++++-----
 linux/m68k/get_syscall_result.c |  5 -----
 8 files changed, 18 insertions(+), 20 deletions(-)
 create mode 100644 linux/m68k/arch_regs.h
 delete mode 100644 linux/m68k/get_syscall_result.c

diff --git a/Makefile.am b/Makefile.am
index e55a0db2..457659fe 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -414,11 +414,11 @@ EXTRA_DIST =				\
 	linux/ia64/userent.h		\
 	linux/inet_diag.h		\
 	linux/m68k/arch_regs.c		\
+	linux/m68k/arch_regs.h		\
 	linux/m68k/arch_sigreturn.c	\
 	linux/m68k/get_error.c		\
 	linux/m68k/get_scno.c		\
 	linux/m68k/get_syscall_args.c	\
-	linux/m68k/get_syscall_result.c	\
 	linux/m68k/ioctls_arch0.h	\
 	linux/m68k/ioctls_inc0.h	\
 	linux/m68k/syscallent.h		\
diff --git a/linux/m68k/arch_regs.c b/linux/m68k/arch_regs.c
index 8f0ab79a..1198762b 100644
--- a/linux/m68k/arch_regs.c
+++ b/linux/m68k/arch_regs.c
@@ -1,2 +1,4 @@
-static long m68k_d0;
-#define ARCH_PC_PEEK_ADDR (4 * PT_PC)
+static struct user_regs_struct m68k_regs;
+long *const m68k_usp_ptr = &m68k_regs.usp;
+#define ARCH_PC_REG m68k_regs.pc
+#define ARCH_REGS_FOR_GETREGS m68k_regs
diff --git a/linux/m68k/arch_regs.h b/linux/m68k/arch_regs.h
new file mode 100644
index 00000000..08293365
--- /dev/null
+++ b/linux/m68k/arch_regs.h
@@ -0,0 +1 @@
+extern long *const m68k_usp_ptr;
diff --git a/linux/m68k/arch_sigreturn.c b/linux/m68k/arch_sigreturn.c
index 0011c174..12e8bded 100644
--- a/linux/m68k/arch_sigreturn.c
+++ b/linux/m68k/arch_sigreturn.c
@@ -3,10 +3,8 @@ arch_sigreturn(struct tcb *tcp)
 {
 	long addr;
 
-	if (upeek(tcp->pid, 4*PT_USP, &addr) < 0)
-		return;
 	/* Fetch pointer to struct sigcontext.  */
-	if (umove(tcp, addr + 2 * sizeof(int), &addr) < 0)
+	if (umove(tcp, *m68k_usp_ptr + 2 * sizeof(int), &addr) < 0)
 		return;
 
 	unsigned long mask[NSIG / 8 / sizeof(long)];
diff --git a/linux/m68k/get_error.c b/linux/m68k/get_error.c
index a792835d..3ad51a08 100644
--- a/linux/m68k/get_error.c
+++ b/linux/m68k/get_error.c
@@ -1,10 +1,10 @@
 static void
 get_error(struct tcb *tcp, const bool check_errno)
 {
-	if (check_errno && is_negated_errno(m68k_d0)) {
+	if (check_errno && is_negated_errno(m68k_regs.d0)) {
 		tcp->u_rval = -1;
-		tcp->u_error = -m68k_d0;
+		tcp->u_error = -m68k_regs.d0;
 	} else {
-		tcp->u_rval = m68k_d0;
+		tcp->u_rval = m68k_regs.d0;
 	}
 }
diff --git a/linux/m68k/get_scno.c b/linux/m68k/get_scno.c
index 716a7616..829f3477 100644
--- a/linux/m68k/get_scno.c
+++ b/linux/m68k/get_scno.c
@@ -2,5 +2,6 @@
 static int
 arch_get_scno(struct tcb *tcp)
 {
-	return upeek(tcp->pid, 4 * PT_ORIG_D0, &tcp->scno) < 0 ? -1 : 1;
+	tcp->scno = m68k_regs.orig_d0;
+	return 1;
 }
diff --git a/linux/m68k/get_syscall_args.c b/linux/m68k/get_syscall_args.c
index bc69a195..8ec3d281 100644
--- a/linux/m68k/get_syscall_args.c
+++ b/linux/m68k/get_syscall_args.c
@@ -2,10 +2,11 @@
 static int
 get_syscall_args(struct tcb *tcp)
 {
-	unsigned int i;
-
-	for (i = 0; i < tcp->s_ent->nargs; ++i)
-		if (upeek(tcp->pid, (i < 5 ? i : i + 2)*4, &tcp->u_arg[i]) < 0)
-			return -1;
+	tcp->u_arg[0] = m68k_regs.d1;
+	tcp->u_arg[1] = m68k_regs.d2;
+	tcp->u_arg[2] = m68k_regs.d3;
+	tcp->u_arg[3] = m68k_regs.d4;
+	tcp->u_arg[4] = m68k_regs.d5;
+	tcp->u_arg[5] = m68k_regs.a0;
 	return 1;
 }
diff --git a/linux/m68k/get_syscall_result.c b/linux/m68k/get_syscall_result.c
deleted file mode 100644
index 005cf60c..00000000
--- a/linux/m68k/get_syscall_result.c
+++ /dev/null
@@ -1,5 +0,0 @@
-static int
-get_syscall_result_regs(struct tcb *tcp)
-{
-	return upeek(tcp->pid, 4 * PT_D0, &m68k_d0) < 0 ? -1 : 0;
-}
-- 
2.40.0