powerpc: switch to ->regset_get()

Note: compat variant of REGSET_TM_CGPR is almost certainly wrong;
it claims to be 48*64bit, but just as compat REGSET_GPR it stores
44*32bit of (truncated) registers + 4 32bit zeros... followed by
48 more 32bit zeroes.  Might be too late to change - it's a userland
ABI, after all ;-/
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

arch/powerpc/kernel/ptrace/ptrace-altivec.c

@@ -41,38 +41,25 @@ int vr_active(struct task_struct *target, const struct user_regset *regset)
  * };
  */
 int vr_get(struct task_struct *target, const struct user_regset *regset,
-	   unsigned int pos, unsigned int count, void *kbuf, void __user *ubuf)
+	   struct membuf to)
 {
-	int ret;
+	union {
+		elf_vrreg_t reg;
+		u32 word;
+	} vrsave;
 
 	flush_altivec_to_thread(target);
 
 	BUILD_BUG_ON(offsetof(struct thread_vr_state, vscr) !=
 		     offsetof(struct thread_vr_state, vr[32]));
 
-	ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
-				  &target->thread.vr_state, 0,
-				  33 * sizeof(vector128));
-	if (!ret) {
-		/*
-		 * Copy out only the low-order word of vrsave.
-		 */
-		int start, end;
-		union {
-			elf_vrreg_t reg;
-			u32 word;
-		} vrsave;
-		memset(&vrsave, 0, sizeof(vrsave));
-
-		vrsave.word = target->thread.vrsave;
-
-		start = 33 * sizeof(vector128);
-		end = start + sizeof(vrsave);
-		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, &vrsave,
-					  start, end);
-	}
-
-	return ret;
+	membuf_write(&to, &target->thread.vr_state, 33 * sizeof(vector128));
+	/*
+	 * Copy out only the low-order word of vrsave.
+	 */
+	memset(&vrsave, 0, sizeof(vrsave));
+	vrsave.word = target->thread.vrsave;
+	return membuf_write(&to, &vrsave, sizeof(vrsave));
 }
 
 /*

arch/powerpc/kernel/ptrace/ptrace-decl.h

@@ -63,8 +63,7 @@ enum powerpc_regset {
 
 /* ptrace-(no)vsx */
 
-int fpr_get(struct task_struct *target, const struct user_regset *regset,
-	    unsigned int pos, unsigned int count, void *kbuf, void __user *ubuf);
+user_regset_get2_fn fpr_get;
 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);
@@ -72,8 +71,7 @@ int fpr_set(struct task_struct *target, const struct user_regset *regset,
 /* ptrace-vsx */
 
 int vsr_active(struct task_struct *target, const struct user_regset *regset);
-int vsr_get(struct task_struct *target, const struct user_regset *regset,
-	    unsigned int pos, unsigned int count, void *kbuf, void __user *ubuf);
+user_regset_get2_fn vsr_get;
 int vsr_set(struct task_struct *target, const struct user_regset *regset,
 	    unsigned int pos, unsigned int count,
 	    const void *kbuf, const void __user *ubuf);
@@ -81,8 +79,7 @@ int vsr_set(struct task_struct *target, const struct user_regset *regset,
 /* ptrace-altivec */
 
 int vr_active(struct task_struct *target, const struct user_regset *regset);
-int vr_get(struct task_struct *target, const struct user_regset *regset,
-	   unsigned int pos, unsigned int count, void *kbuf, void __user *ubuf);
+user_regset_get2_fn vr_get;
 int vr_set(struct task_struct *target, const struct user_regset *regset,
 	   unsigned int pos, unsigned int count,
 	   const void *kbuf, const void __user *ubuf);
@@ -90,8 +87,7 @@ int vr_set(struct task_struct *target, const struct user_regset *regset,
 /* ptrace-spe */
 
 int evr_active(struct task_struct *target, const struct user_regset *regset);
-int evr_get(struct task_struct *target, const struct user_regset *regset,
-	    unsigned int pos, unsigned int count, void *kbuf, void __user *ubuf);
+user_regset_get2_fn evr_get;
 int evr_set(struct task_struct *target, const struct user_regset *regset,
 	    unsigned int pos, unsigned int count,
 	    const void *kbuf, const void __user *ubuf);
@@ -100,9 +96,8 @@ int evr_set(struct task_struct *target, const struct user_regset *regset,
 
 int gpr32_get_common(struct task_struct *target,
 		     const struct user_regset *regset,
-		     unsigned int pos, unsigned int count,
-			    void *kbuf, void __user *ubuf,
-			    unsigned long *regs);
+		     struct membuf to,
+		     unsigned long *regs);
 int gpr32_set_common(struct task_struct *target,
 		     const struct user_regset *regset,
 		     unsigned int pos, unsigned int count,
@@ -118,55 +113,46 @@ static inline void flush_tmregs_to_thread(struct task_struct *tsk) { }
 #endif
 
 int tm_cgpr_active(struct task_struct *target, const struct user_regset *regset);
-int tm_cgpr_get(struct task_struct *target, const struct user_regset *regset,
-		unsigned int pos, unsigned int count, void *kbuf, void __user *ubuf);
+user_regset_get2_fn tm_cgpr_get;
 int tm_cgpr_set(struct task_struct *target, const struct user_regset *regset,
 		unsigned int pos, unsigned int count,
 		const void *kbuf, const void __user *ubuf);
 int tm_cfpr_active(struct task_struct *target, const struct user_regset *regset);
-int tm_cfpr_get(struct task_struct *target, const struct user_regset *regset,
-		unsigned int pos, unsigned int count, void *kbuf, void __user *ubuf);
+user_regset_get2_fn tm_cfpr_get;
 int tm_cfpr_set(struct task_struct *target, const struct user_regset *regset,
 		unsigned int pos, unsigned int count,
 		const void *kbuf, const void __user *ubuf);
 int tm_cvmx_active(struct task_struct *target, const struct user_regset *regset);
-int tm_cvmx_get(struct task_struct *target, const struct user_regset *regset,
-		unsigned int pos, unsigned int count, void *kbuf, void __user *ubuf);
+user_regset_get2_fn tm_cvmx_get;
 int tm_cvmx_set(struct task_struct *target, const struct user_regset *regset,
 		unsigned int pos, unsigned int count,
 		const void *kbuf, const void __user *ubuf);
 int tm_cvsx_active(struct task_struct *target, const struct user_regset *regset);
-int tm_cvsx_get(struct task_struct *target, const struct user_regset *regset,
-		unsigned int pos, unsigned int count, void *kbuf, void __user *ubuf);
+user_regset_get2_fn tm_cvsx_get;
 int tm_cvsx_set(struct task_struct *target, const struct user_regset *regset,
 		unsigned int pos, unsigned int count,
 		const void *kbuf, const void __user *ubuf);
 int tm_spr_active(struct task_struct *target, const struct user_regset *regset);
-int tm_spr_get(struct task_struct *target, const struct user_regset *regset,
-	       unsigned int pos, unsigned int count, void *kbuf, void __user *ubuf);
+user_regset_get2_fn tm_spr_get;
 int tm_spr_set(struct task_struct *target, const struct user_regset *regset,
 	       unsigned int pos, unsigned int count,
 	       const void *kbuf, const void __user *ubuf);
 int tm_tar_active(struct task_struct *target, const struct user_regset *regset);
-int tm_tar_get(struct task_struct *target, const struct user_regset *regset,
-	       unsigned int pos, unsigned int count, void *kbuf, void __user *ubuf);
+user_regset_get2_fn tm_tar_get;
 int tm_tar_set(struct task_struct *target, const struct user_regset *regset,
 	       unsigned int pos, unsigned int count,
 	       const void *kbuf, const void __user *ubuf);
 int tm_ppr_active(struct task_struct *target, const struct user_regset *regset);
-int tm_ppr_get(struct task_struct *target, const struct user_regset *regset,
-	       unsigned int pos, unsigned int count, void *kbuf, void __user *ubuf);
+user_regset_get2_fn tm_ppr_get;
 int tm_ppr_set(struct task_struct *target, const struct user_regset *regset,
 	       unsigned int pos, unsigned int count,
 	       const void *kbuf, const void __user *ubuf);
 int tm_dscr_active(struct task_struct *target, const struct user_regset *regset);
-int tm_dscr_get(struct task_struct *target, const struct user_regset *regset,
-		unsigned int pos, unsigned int count, void *kbuf, void __user *ubuf);
+user_regset_get2_fn tm_dscr_get;
 int tm_dscr_set(struct task_struct *target, const struct user_regset *regset,
 		unsigned int pos, unsigned int count,
 		const void *kbuf, const void __user *ubuf);
-int tm_cgpr32_get(struct task_struct *target, const struct user_regset *regset,
-		  unsigned int pos, unsigned int count, void *kbuf, void __user *ubuf);
+user_regset_get2_fn tm_cgpr32_get;
 int tm_cgpr32_set(struct task_struct *target, const struct user_regset *regset,
 		  unsigned int pos, unsigned int count,
 		  const void *kbuf, const void __user *ubuf);

arch/powerpc/kernel/ptrace/ptrace-novsx.c

@@ -19,15 +19,14 @@
  * };
  */
 int fpr_get(struct task_struct *target, const struct user_regset *regset,
-	    unsigned int pos, unsigned int count, void *kbuf, void __user *ubuf)
+	    struct membuf to)
 {
 	BUILD_BUG_ON(offsetof(struct thread_fp_state, fpscr) !=
 		     offsetof(struct thread_fp_state, fpr[32]));
 
 	flush_fp_to_thread(target);
 
-	return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
-				   &target->thread.fp_state, 0, -1);
+	return membuf_write(&to, &target->thread.fp_state, 33 * sizeof(u64));
 }
 
 /*

arch/powerpc/kernel/ptrace/ptrace-spe.c

@@ -23,25 +23,17 @@ int evr_active(struct task_struct *target, const struct user_regset *regset)
 }
 
 int evr_get(struct task_struct *target, const struct user_regset *regset,
-	    unsigned int pos, unsigned int count, void *kbuf, void __user *ubuf)
+	    struct membuf to)
 {
-	int ret;
-
 	flush_spe_to_thread(target);
 
-	ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
-				  &target->thread.evr,
-				  0, sizeof(target->thread.evr));
+	membuf_write(&to, &target->thread.evr, sizeof(target->thread.evr));
 
 	BUILD_BUG_ON(offsetof(struct thread_struct, acc) + sizeof(u64) !=
 		     offsetof(struct thread_struct, spefscr));
 
-	if (!ret)
-		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
-					  &target->thread.acc,
-					  sizeof(target->thread.evr), -1);
-
-	return ret;
+	return membuf_write(&to, &target->thread.acc,
+				sizeof(u64) + sizeof(u32));
 }
 
 int evr_set(struct task_struct *target, const struct user_regset *regset,

arch/powerpc/kernel/ptrace/ptrace-vsx.c

@@ -19,7 +19,7 @@
  * };
  */
 int fpr_get(struct task_struct *target, const struct user_regset *regset,
-	    unsigned int pos, unsigned int count, void *kbuf, void __user *ubuf)
+	    struct membuf to)
 {
 	u64 buf[33];
 	int i;
@@ -30,7 +30,7 @@ int fpr_get(struct task_struct *target, const struct user_regset *regset,
 	for (i = 0; i < 32 ; i++)
 		buf[i] = target->thread.TS_FPR(i);
 	buf[32] = target->thread.fp_state.fpscr;
-	return user_regset_copyout(&pos, &count, &kbuf, &ubuf, buf, 0, -1);
+	return membuf_write(&to, buf, 33 * sizeof(u64));
 }
 
 /*
@@ -95,10 +95,10 @@ int vsr_active(struct task_struct *target, const struct user_regset *regset)
  * };
  */
 int vsr_get(struct task_struct *target, const struct user_regset *regset,
-	    unsigned int pos, unsigned int count, void *kbuf, void __user *ubuf)
+	    struct membuf to)
 {
 	u64 buf[32];
-	int ret, i;
+	int i;
 
 	flush_tmregs_to_thread(target);
 	flush_fp_to_thread(target);
@@ -108,10 +108,7 @@ int vsr_get(struct task_struct *target, const struct user_regset *regset,
 	for (i = 0; i < 32 ; i++)
 		buf[i] = target->thread.fp_state.fpr[i][TS_VSRLOWOFFSET];
 
-	ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
-				  buf, 0, 32 * sizeof(double));
-
-	return ret;
+	return membuf_write(&to, buf, 32 * sizeof(double));
 }
 
 /*