From: Matthew Wilcox <willy@infradead.org>
Date: Mon, 18 Feb 2019 22:17:56 +0000 (-0500)
Subject: spi: Convert spi_master_idr to XArray
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=76bac5db85e180a2d2bc388e8a719ce64f5a2cfb;p=users%2Fwilly%2Fxarray.git

spi: Convert spi_master_idr to XArray

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

diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index 75ac046cae52..2ae55af60666 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -31,7 +31,7 @@
 #include <linux/ioport.h>
 #include <linux/acpi.h>
 #include <linux/highmem.h>
-#include <linux/idr.h>
+#include <linux/xarray.h>
 #include <linux/platform_data/x86/apple.h>
 
 #define CREATE_TRACE_POINTS
@@ -41,7 +41,7 @@ EXPORT_TRACEPOINT_SYMBOL(spi_transfer_stop);
 
 #include "internals.h"
 
-static DEFINE_IDR(spi_master_idr);
+static DEFINE_XARRAY_ALLOC(spi_masters);
 
 static void spidev_release(struct device *dev)
 {
@@ -471,7 +471,6 @@ static LIST_HEAD(spi_controller_list);
 /*
  * Used to protect add/del opertion for board_info list and
  * spi_controller list, and their matching process
- * also used to protect object of type struct idr
  */
 static DEFINE_MUTEX(board_lock);
 
@@ -2379,7 +2378,6 @@ int spi_register_controller(struct spi_controller *ctlr)
 	struct device		*dev = ctlr->dev.parent;
 	struct boardinfo	*bi;
 	int			status;
-	int			id, first_dynamic;
 
 	if (!dev)
 		return -ENODEV;
@@ -2392,43 +2390,36 @@ int spi_register_controller(struct spi_controller *ctlr)
 	if (status)
 		return status;
 
+	if ((ctlr->bus_num < 0) && ctlr->dev.of_node) {
+		status = of_alias_get_id(ctlr->dev.of_node, "spi");
+		if (status >= 0)
+			ctlr->bus_num = status;
+	}
+
 	if (ctlr->bus_num >= 0) {
 		/* devices with a fixed bus num must check-in with the num */
 		mutex_lock(&board_lock);
-		id = idr_alloc(&spi_master_idr, ctlr, ctlr->bus_num,
-			ctlr->bus_num + 1, GFP_KERNEL);
+		status = xa_insert(&spi_masters, ctlr->bus_num, ctlr,
+				GFP_KERNEL);
 		mutex_unlock(&board_lock);
-		if (WARN(id < 0, "couldn't get idr"))
-			return id == -ENOSPC ? -EBUSY : id;
-		ctlr->bus_num = id;
-	} else if (ctlr->dev.of_node) {
-		/* allocate dynamic bus number using Linux idr */
-		id = of_alias_get_id(ctlr->dev.of_node, "spi");
-		if (id >= 0) {
-			ctlr->bus_num = id;
-			mutex_lock(&board_lock);
-			id = idr_alloc(&spi_master_idr, ctlr, ctlr->bus_num,
-				       ctlr->bus_num + 1, GFP_KERNEL);
-			mutex_unlock(&board_lock);
-			if (WARN(id < 0, "couldn't get idr"))
-				return id == -ENOSPC ? -EBUSY : id;
-		}
-	}
-	if (ctlr->bus_num < 0) {
-		first_dynamic = of_alias_get_highest_id("spi");
+	} else {
+		int id, first_dynamic = of_alias_get_highest_id("spi");
+
 		if (first_dynamic < 0)
 			first_dynamic = 0;
 		else
 			first_dynamic++;
 
 		mutex_lock(&board_lock);
-		id = idr_alloc(&spi_master_idr, ctlr, first_dynamic,
-			       0, GFP_KERNEL);
+		status = xa_alloc(&spi_masters, &id, ctlr,
+				XA_LIMIT(first_dynamic, INT_MAX), GFP_KERNEL);
+		if (!status)
+			ctlr->bus_num = id;
 		mutex_unlock(&board_lock);
-		if (WARN(id < 0, "couldn't get idr"))
-			return id;
-		ctlr->bus_num = id;
 	}
+	if (WARN(status < 0, "couldn't get id"))
+		return status;
+
 	INIT_LIST_HEAD(&ctlr->queue);
 	spin_lock_init(&ctlr->queue_lock);
 	spin_lock_init(&ctlr->bus_lock_spinlock);
@@ -2473,7 +2464,7 @@ int spi_register_controller(struct spi_controller *ctlr)
 	if (status < 0) {
 		/* free bus id */
 		mutex_lock(&board_lock);
-		idr_remove(&spi_master_idr, ctlr->bus_num);
+		xa_erase(&spi_masters, ctlr->bus_num);
 		mutex_unlock(&board_lock);
 		goto done;
 	}
@@ -2494,7 +2485,7 @@ int spi_register_controller(struct spi_controller *ctlr)
 			device_del(&ctlr->dev);
 			/* free bus id */
 			mutex_lock(&board_lock);
-			idr_remove(&spi_master_idr, ctlr->bus_num);
+			xa_erase(&spi_masters, ctlr->bus_num);
 			mutex_unlock(&board_lock);
 			goto done;
 		}
@@ -2580,9 +2571,7 @@ void spi_unregister_controller(struct spi_controller *ctlr)
 	int id = ctlr->bus_num;
 
 	/* First make sure that this controller was ever added */
-	mutex_lock(&board_lock);
-	found = idr_find(&spi_master_idr, id);
-	mutex_unlock(&board_lock);
+	found = xa_load(&spi_masters, id);
 	if (ctlr->queued) {
 		if (spi_destroy_queue(ctlr))
 			dev_err(&ctlr->dev, "queue remove failed\n");
@@ -2596,7 +2585,7 @@ void spi_unregister_controller(struct spi_controller *ctlr)
 	/* free bus id */
 	mutex_lock(&board_lock);
 	if (found == ctlr)
-		idr_remove(&spi_master_idr, id);
+		xa_erase(&spi_masters, id);
 	mutex_unlock(&board_lock);
 }
 EXPORT_SYMBOL_GPL(spi_unregister_controller);