floppy: cleanup: do not iterate on current_fdc in DMA grab/release fu…

…nctions

Both floppy_grab_irq_and_dma() and floppy_release_irq_and_dma() used to
iterate on the global variable while setting up or freeing resources.
Now that they exclusively rely on functions which take the fdc as an
argument, so let's not touch the global one anymore.

Link: https://lore.kernel.org/r/20200331094054.24441-23-w@1wt.eu
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Denis Efremov <efremov@linux.com>

drivers/block/floppy.c

@@ -4854,6 +4854,8 @@ static void floppy_release_regions(int fdc)
 
 static int floppy_grab_irq_and_dma(void)
 {
+	int fdc;
+
 	if (atomic_inc_return(&usage_count) > 1)
 		return 0;
 
@@ -4881,24 +4883,24 @@ static int floppy_grab_irq_and_dma(void)
 		}
 	}
 
-	for (current_fdc = 0; current_fdc < N_FDC; current_fdc++) {
-		if (fdc_state[current_fdc].address != -1) {
-			if (floppy_request_regions(current_fdc))
+	for (fdc = 0; fdc < N_FDC; fdc++) {
+		if (fdc_state[fdc].address != -1) {
+			if (floppy_request_regions(fdc))
 				goto cleanup;
 		}
 	}
-	for (current_fdc = 0; current_fdc < N_FDC; current_fdc++) {
-		if (fdc_state[current_fdc].address != -1) {
-			reset_fdc_info(current_fdc, 1);
-			fdc_outb(fdc_state[current_fdc].dor, current_fdc, FD_DOR);
+	for (fdc = 0; fdc < N_FDC; fdc++) {
+		if (fdc_state[fdc].address != -1) {
+			reset_fdc_info(fdc, 1);
+			fdc_outb(fdc_state[fdc].dor, fdc, FD_DOR);
 		}
 	}
-	current_fdc = 0;
+
 	set_dor(0, ~0, 8);	/* avoid immediate interrupt */
 
-	for (current_fdc = 0; current_fdc < N_FDC; current_fdc++)
-		if (fdc_state[current_fdc].address != -1)
-			fdc_outb(fdc_state[current_fdc].dor, current_fdc, FD_DOR);
+	for (fdc = 0; fdc < N_FDC; fdc++)
+		if (fdc_state[fdc].address != -1)
+			fdc_outb(fdc_state[fdc].dor, fdc, FD_DOR);
 	/*
 	 * The driver will try and free resources and relies on us
 	 * to know if they were allocated or not.
@@ -4909,15 +4911,16 @@ static int floppy_grab_irq_and_dma(void)
 cleanup:
 	fd_free_irq();
 	fd_free_dma();
-	while (--current_fdc >= 0)
-		floppy_release_regions(current_fdc);
+	while (--fdc >= 0)
+		floppy_release_regions(fdc);
+	current_fdc = 0;
 	atomic_dec(&usage_count);
 	return -1;
 }
 
 static void floppy_release_irq_and_dma(void)
 {
-	int old_fdc;
+	int fdc;
 #ifndef __sparc__
 	int drive;
 #endif
@@ -4958,11 +4961,9 @@ static void floppy_release_irq_and_dma(void)
 		pr_info("auxiliary floppy timer still active\n");
 	if (work_pending(&floppy_work))
 		pr_info("work still pending\n");
-	old_fdc = current_fdc;
-	for (current_fdc = 0; current_fdc < N_FDC; current_fdc++)
-		if (fdc_state[current_fdc].address != -1)
-			floppy_release_regions(current_fdc);
-	current_fdc = old_fdc;
+	for (fdc = 0; fdc < N_FDC; fdc++)
+		if (fdc_state[fdc].address != -1)
+			floppy_release_regions(fdc);
 }
 
 #ifdef MODULE