MIPS: Implement task_user_regset_view.

There are no users yet of task_user_regset_view. yet; users will be
implemented rsp activated in subsequent commits.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 129 insertions, 0 deletions

diff --git a/arch/mips/kernel/ptrace.c b/arch/mips/kernel/ptrace.c
index 7a5d7ac6b0d4..83a6a464db70 100644
--- a/arch/mips/kernel/ptrace.c
+++ b/arch/mips/kernel/ptrace.c
@@ -16,11 +16,13 @@
  */
 #include <linux/compiler.h>
 #include <linux/context_tracking.h>
+#include <linux/elf.h>
 #include <linux/kernel.h>
 #include <linux/sched.h>
 #include <linux/mm.h>
 #include <linux/errno.h>
 #include <linux/ptrace.h>
+#include <linux/regset.h>
 #include <linux/smp.h>
 #include <linux/user.h>
 #include <linux/security.h>
@@ -256,6 +258,133 @@ int ptrace_set_watch_regs(struct task_struct *child,
         return 0;
 }
 
+/* regset get/set implementations */
+
+static int gpr_get(struct task_struct *target,
+                   const struct user_regset *regset,
+                   unsigned int pos, unsigned int count,
+                   void *kbuf, void __user *ubuf)
+{
+        struct pt_regs *regs = task_pt_regs(target);
+
+        return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
+                                   regs, 0, sizeof(*regs));
+}
+
+static int gpr_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 newregs;
+        int ret;
+
+        ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+                                 &newregs,
+                                 0, sizeof(newregs));
+        if (ret)
+                return ret;
+
+        *task_pt_regs(target) = newregs;
+
+        return 0;
+}
+
+static int fpr_get(struct task_struct *target,
+                   const struct user_regset *regset,
+                   unsigned int pos, unsigned int count,
+                   void *kbuf, void __user *ubuf)
+{
+        return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
+                                   &target->thread.fpu,
+                                   0, sizeof(elf_fpregset_t));
+        /* XXX fcr31  */
+}
+
+static int fpr_set(struct task_struct *target,
+                   const struct user_regset *regset,
+                   unsigned int pos, unsigned int count,
+                   const void *kbuf, const void __user *ubuf)
+{
+        return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+                                  &target->thread.fpu,
+                                  0, sizeof(elf_fpregset_t));
+        /* XXX fcr31  */
+}
+
+enum mips_regset {
+        REGSET_GPR,
+        REGSET_FPR,
+};
+
+static const struct user_regset mips_regsets[] = {
+        [REGSET_GPR] = {
+                .core_note_type = NT_PRSTATUS,
+                .n              = ELF_NGREG,
+                .size           = sizeof(unsigned int),
+                .align          = sizeof(unsigned int),
+                .get            = gpr_get,
+                .set            = gpr_set,
+        },
+        [REGSET_FPR] = {
+                .core_note_type = NT_PRFPREG,
+                .n              = ELF_NFPREG,
+                .size           = sizeof(elf_fpreg_t),
+                .align          = sizeof(elf_fpreg_t),
+                .get            = fpr_get,
+                .set            = fpr_set,
+        },
+};
+
+static const struct user_regset_view user_mips_view = {
+        .name           = "mips",
+        .e_machine      = ELF_ARCH,
+        .ei_osabi       = ELF_OSABI,
+        .regsets        = mips_regsets,
+        .n              = ARRAY_SIZE(mips_regsets),
+};
+
+static const struct user_regset mips64_regsets[] = {
+        [REGSET_GPR] = {
+                .core_note_type = NT_PRSTATUS,
+                .n              = ELF_NGREG,
+                .size           = sizeof(unsigned long),
+                .align          = sizeof(unsigned long),
+                .get            = gpr_get,
+                .set            = gpr_set,
+        },
+        [REGSET_FPR] = {
+                .core_note_type = NT_PRFPREG,
+                .n              = ELF_NFPREG,
+                .size           = sizeof(elf_fpreg_t),
+                .align          = sizeof(elf_fpreg_t),
+                .get            = fpr_get,
+                .set            = fpr_set,
+        },
+};
+
+static const struct user_regset_view user_mips64_view = {
+        .name           = "mips",
+        .e_machine      = ELF_ARCH,
+        .ei_osabi       = ELF_OSABI,
+        .regsets        = mips64_regsets,
+        .n              = ARRAY_SIZE(mips_regsets),
+};
+
+const struct user_regset_view *task_user_regset_view(struct task_struct *task)
+{
+#ifdef CONFIG_32BIT
+        return &user_mips_view;
+#endif
+
+#ifdef CONFIG_MIPS32_O32
+                if (test_thread_flag(TIF_32BIT_REGS))
+                        return &user_mips_view;
+#endif
+
+        return &user_mips64_view;
+}
+
 long arch_ptrace(struct task_struct *child, long request,
                  unsigned long addr, unsigned long data)
 {