sparc64: switch genregs32_get() to use of get_from_target()

... for fetching the register window from target's stack, rather
than open-coding it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --git a/arch/sparc/kernel/ptrace_64.c b/arch/sparc/kernel/ptrace_64.c
index 7122efb..f7b2ddf 100644 (file)
--- a/arch/sparc/kernel/ptrace_64.c
+++ b/arch/sparc/kernel/ptrace_64.c
@@ -518,10 +518,10 @@ static int genregs32_get(struct task_struct *target,
                         void *kbuf, void __user *ubuf)
 {
        const struct pt_regs *regs = task_pt_regs(target);
-       compat_ulong_t __user *reg_window;
        compat_ulong_t *k = kbuf;
        compat_ulong_t __user *u = ubuf;
-       compat_ulong_t reg;
+       u32 uregs[16];
+       u32 reg;
 
        if (target == current)
                flushw_user();
@@ -533,52 +533,25 @@ static int genregs32_get(struct task_struct *target,
                for (; count > 0 && pos < 16; count--)
                        *k++ = regs->u_regs[pos++];
 
-               reg_window = (compat_ulong_t __user *) regs->u_regs[UREG_I6];
-               reg_window -= 16;
-               if (target == current) {
-                       for (; count > 0 && pos < 32; count--) {
-                               if (get_user(*k++, &reg_window[pos++]))
-                                       return -EFAULT;
-                       }
-               } else {
-                       for (; count > 0 && pos < 32; count--) {
-                               if (access_process_vm(target,
-                                                     (unsigned long)
-                                                     &reg_window[pos],
-                                                     k, sizeof(*k),
-                                                     FOLL_FORCE)
-                                   != sizeof(*k))
-                                       return -EFAULT;
-                               k++;
-                               pos++;
-                       }
+               if (count && pos < 32) {
+                       if (get_from_target(target, regs->u_regs[UREG_I6],
+                                       uregs, sizeof(uregs)))
+                               return -EFAULT;
+                       for (; count > 0 && pos < 32; count--)
+                               *k++ = uregs[pos++ - 16];
+
                }
        } else {
-               for (; count > 0 && pos < 16; count--) {
+               for (; count > 0 && pos < 16; count--)
                        if (put_user((compat_ulong_t) regs->u_regs[pos++], u++))
                                return -EFAULT;
-               }
-
-               reg_window = (compat_ulong_t __user *) regs->u_regs[UREG_I6];
-               reg_window -= 16;
-               if (target == current) {
-                       for (; count > 0 && pos < 32; count--) {
-                               if (get_user(reg, &reg_window[pos++]) ||
-                                   put_user(reg, u++))
-                                       return -EFAULT;
-                       }
-               } else {
-                       for (; count > 0 && pos < 32; count--) {
-                               if (access_process_vm(target,
-                                                     (unsigned long)
-                                                     &reg_window[pos++],
-                                                     &reg, sizeof(reg),
-                                                     FOLL_FORCE)
-                                   != sizeof(reg))
-                                       return -EFAULT;
-                               if (put_user(reg, u++))
+               if (count && pos < 32) {
+                       if (get_from_target(target, regs->u_regs[UREG_I6],
+                                       uregs, sizeof(uregs)))
+                               return -EFAULT;
+                       for (; count > 0 && pos < 32; count--)
+                               if (put_user(uregs[pos++ - 16], u++))
                                        return -EFAULT;
-                       }
                }
        }
        while (count > 0) {