From: Matthew Wilcox <willy@infradead.org>
Date: Fri, 15 Feb 2019 20:38:03 +0000 (-0500)
Subject: arm_scmi: Convert scmi_protocols to XArray
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=3ad0cefab648b2959de7bf2dd1a3b55337ea5ebd;p=users%2Fwilly%2Fxarray.git

arm_scmi: Convert scmi_protocols to XArray

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

diff --git a/drivers/firmware/arm_scmi/bus.c b/drivers/firmware/arm_scmi/bus.c
index 92f843eaf1e0..ba175a7dcf52 100644
--- a/drivers/firmware/arm_scmi/bus.c
+++ b/drivers/firmware/arm_scmi/bus.c
@@ -16,8 +16,7 @@
 #include "common.h"
 
 static DEFINE_IDA(scmi_bus_id);
-static DEFINE_IDR(scmi_protocols);
-static DEFINE_SPINLOCK(protocol_lock);
+static DEFINE_XARRAY(scmi_protocols);
 
 static const struct scmi_device_id *
 scmi_dev_match_id(struct scmi_device *scmi_dev, struct scmi_driver *scmi_drv)
@@ -49,7 +48,7 @@ static int scmi_dev_match(struct device *dev, struct device_driver *drv)
 
 static int scmi_protocol_init(int protocol_id, struct scmi_handle *handle)
 {
-	scmi_prot_init_fn_t fn = idr_find(&scmi_protocols, protocol_id);
+	scmi_prot_init_fn_t fn = xa_load(&scmi_protocols, protocol_id);
 
 	if (unlikely(!fn))
 		return -EINVAL;
@@ -175,11 +174,10 @@ int scmi_protocol_register(int protocol_id, scmi_prot_init_fn_t fn)
 {
 	int ret;
 
-	spin_lock(&protocol_lock);
-	ret = idr_alloc(&scmi_protocols, fn, protocol_id, protocol_id + 1,
-			GFP_ATOMIC);
-	spin_unlock(&protocol_lock);
-	if (ret != protocol_id)
+	ret = xa_insert(&scmi_protocols, protocol_id, fn, GFP_ATOMIC);
+	if (ret == 0)
+		ret = protocol_id;
+	else
 		pr_err("unable to allocate SCMI idr slot, err %d\n", ret);
 
 	return ret;
@@ -188,9 +186,7 @@ EXPORT_SYMBOL_GPL(scmi_protocol_register);
 
 void scmi_protocol_unregister(int protocol_id)
 {
-	spin_lock(&protocol_lock);
-	idr_remove(&scmi_protocols, protocol_id);
-	spin_unlock(&protocol_lock);
+	xa_erase(&scmi_protocols, protocol_id);
 }
 EXPORT_SYMBOL_GPL(scmi_protocol_unregister);