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;