arm64/signal: Make interface for restore_fpsimd_context() consistent

Instead of taking a pointer to struct user_ctxs like the other two
restore_blah_context() functions the FPSIMD function takes a pointer to the
user struct it should read. Change it to be consistent with the rest, both
for consistency and to prepare for changes which avoid rereading data that
has already been read by the core parsing code.

There should be no functional change from this patch.

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20221212-arm64-signal-cleanup-v3-3-4545c94b20ff@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

Author: broonie

arch/arm64/kernel/signal.c

@@ -170,6 +170,14 @@ static void __user *apply_user_offset(
 	return base + offset;
 }
 
+struct user_ctxs {
+	struct fpsimd_context __user *fpsimd;
+	struct sve_context __user *sve;
+	struct tpidr2_context __user *tpidr2;
+	struct za_context __user *za;
+	struct zt_context __user *zt;
+};
+
 static int preserve_fpsimd_context(struct fpsimd_context __user *ctx)
 {
 	struct user_fpsimd_state const *fpsimd =
@@ -188,24 +196,24 @@ static int preserve_fpsimd_context(struct fpsimd_context __user *ctx)
 	return err ? -EFAULT : 0;
 }
 
-static int restore_fpsimd_context(struct fpsimd_context __user *ctx)
+static int restore_fpsimd_context(struct user_ctxs *user)
 {
 	struct user_fpsimd_state fpsimd;
 	__u32 size;
 	int err = 0;
 
 	/* check the size information */
-	__get_user_error(size, &ctx->head.size, err);
+	__get_user_error(size, &user->fpsimd->head.size, err);
 	if (err)
 		return -EFAULT;
 	if (size != sizeof(struct fpsimd_context))
 		return -EINVAL;
 
 	/* copy the FP and status/control registers */
-	err = __copy_from_user(fpsimd.vregs, ctx->vregs,
+	err = __copy_from_user(fpsimd.vregs, &(user->fpsimd->vregs),
 			       sizeof(fpsimd.vregs));
-	__get_user_error(fpsimd.fpsr, &ctx->fpsr, err);
-	__get_user_error(fpsimd.fpcr, &ctx->fpcr, err);
+	__get_user_error(fpsimd.fpsr, &(user->fpsimd->fpsr), err);
+	__get_user_error(fpsimd.fpcr, &(user->fpsimd->fpcr), err);
 
 	clear_thread_flag(TIF_SVE);
 	current->thread.fp_type = FP_STATE_FPSIMD;
@@ -218,14 +226,6 @@ static int restore_fpsimd_context(struct fpsimd_context __user *ctx)
 }
 
 
-struct user_ctxs {
-	struct fpsimd_context __user *fpsimd;
-	struct sve_context __user *sve;
-	struct tpidr2_context __user *tpidr2;
-	struct za_context __user *za;
-	struct zt_context __user *zt;
-};
-
 #ifdef CONFIG_ARM64_SVE
 
 static int preserve_sve_context(struct sve_context __user *ctx)
@@ -789,7 +789,7 @@ static int restore_sigframe(struct pt_regs *regs,
 		if (user.sve)
 			err = restore_sve_fpsimd_context(&user);
 		else
-			err = restore_fpsimd_context(user.fpsimd);
+			err = restore_fpsimd_context(&user);
 	}
 
 	if (err == 0 && system_supports_sme() && user.tpidr2)