From: Matthew Wilcox <willy@infradead.org>
Date: Mon, 18 Feb 2019 22:21:05 +0000 (-0500)
Subject: greybus: Convert uart tty_minors to XArray
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=82c8e8fe66511ec7d795ca0e2ecd99ba5a13c3eb;p=users%2Fwilly%2Fxarray.git

greybus: Convert uart tty_minors to XArray

Signed-off-by: Matthew Wilcox <willy@infradead.org>
---

diff --git a/drivers/staging/greybus/uart.c b/drivers/staging/greybus/uart.c
index b3bffe91ae99..0b5b0488785d 100644
--- a/drivers/staging/greybus/uart.c
+++ b/drivers/staging/greybus/uart.c
@@ -75,7 +75,7 @@ struct gb_tty {
 };
 
 static struct tty_driver *gb_tty_driver;
-static DEFINE_IDR(tty_minors);
+static DEFINE_XARRAY_ALLOC(tty_minors);
 static DEFINE_MUTEX(table_lock);
 
 static int gb_uart_receive_data_handler(struct gb_operation *op)
@@ -353,7 +353,7 @@ static struct gb_tty *get_gb_by_minor(unsigned int minor)
 	struct gb_tty *gb_tty;
 
 	mutex_lock(&table_lock);
-	gb_tty = idr_find(&tty_minors, minor);
+	gb_tty = xa_load(&tty_minors, minor);
 	if (gb_tty) {
 		mutex_lock(&gb_tty->mutex);
 		if (gb_tty->disconnected) {
@@ -370,14 +370,14 @@ static struct gb_tty *get_gb_by_minor(unsigned int minor)
 
 static int alloc_minor(struct gb_tty *gb_tty)
 {
-	int minor;
+	int err;
 
 	mutex_lock(&table_lock);
-	minor = idr_alloc(&tty_minors, gb_tty, 0, GB_NUM_MINORS, GFP_KERNEL);
+	err = xa_alloc(&tty_minors, &gb_tty->minor, gb_tty,
+			XA_LIMIT(0, GB_NUM_MINORS - 1), GFP_KERNEL);
 	mutex_unlock(&table_lock);
-	if (minor >= 0)
-		gb_tty->minor = minor;
-	return minor;
+
+	return err;
 }
 
 static void release_minor(struct gb_tty *gb_tty)
@@ -386,7 +386,7 @@ static void release_minor(struct gb_tty *gb_tty)
 
 	gb_tty->minor = 0;	/* Maybe should use an invalid value instead */
 	mutex_lock(&table_lock);
-	idr_remove(&tty_minors, minor);
+	xa_erase(&tty_minors, minor);
 	mutex_unlock(&table_lock);
 }
 
@@ -1009,7 +1009,6 @@ static void gb_tty_exit(void)
 {
 	tty_unregister_driver(gb_tty_driver);
 	put_tty_driver(gb_tty_driver);
-	idr_destroy(&tty_minors);
 }
 
 static const struct gbphy_device_id gb_uart_id_table[] = {