x86/ioperm: Save an indentation level in tss_update_io_bitmap()

... for better readability.

No functional changes.

[ Minor edit. ]
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/kernel/process.c

@@ -377,19 +377,22 @@ static void tss_copy_io_bitmap(struct tss_struct *tss, struct io_bitmap *iobm)
 void tss_update_io_bitmap(void)
 {
 	struct tss_struct *tss = this_cpu_ptr(&cpu_tss_rw);
+	struct thread_struct *t = &current->thread;
 	u16 *base = &tss->x86_tss.io_bitmap_base;
 
-	if (test_thread_flag(TIF_IO_BITMAP)) {
-		struct thread_struct *t = &current->thread;
+	if (!test_thread_flag(TIF_IO_BITMAP)) {
+		tss_invalidate_io_bitmap(tss);
+		return;
+	}
 
 	if (IS_ENABLED(CONFIG_X86_IOPL_IOPERM) && t->iopl_emul == 3) {
 		*base = IO_BITMAP_OFFSET_VALID_ALL;
 	} else {
 		struct io_bitmap *iobm = t->io_bitmap;
+
 		/*
-			 * Only copy bitmap data when the sequence number
-			 * differs. The update time is accounted to the
-			 * incoming task.
+		 * Only copy bitmap data when the sequence number differs. The
+		 * update time is accounted to the incoming task.
 		 */
 		if (tss->io_bitmap.prev_sequence != iobm->sequence)
 			tss_copy_io_bitmap(tss, iobm);
@@ -397,17 +400,14 @@ void tss_update_io_bitmap(void)
 		/* Enable the bitmap */
 		*base = IO_BITMAP_OFFSET_VALID_MAP;
 	}
+
 	/*
-		 * Make sure that the TSS limit is covering the io bitmap.
-		 * It might have been cut down by a VMEXIT to 0x67 which
-		 * would cause a subsequent I/O access from user space to
-		 * trigger a #GP because tbe bitmap is outside the TSS
-		 * limit.
+	 * Make sure that the TSS limit is covering the IO bitmap. It might have
+	 * been cut down by a VMEXIT to 0x67 which would cause a subsequent I/O
+	 * access from user space to trigger a #GP because tbe bitmap is outside
+	 * the TSS limit.
 	 */
 	refresh_tss_limit();
-	} else {
-		tss_invalidate_io_bitmap(tss);
-	}
 }
 #else /* CONFIG_X86_IOPL_IOPERM */
 static inline void switch_to_bitmap(unsigned long tifp) { }