From: Matthew Wilcox <willy@infradead.org>
Date: Mon, 18 Feb 2019 22:36:36 +0000 (-0500)
Subject: bcm2835-camera: Convert context_map to XArray
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=8672bbe52f39c6ad6cf841f8e5ad1bac2da88d5a;p=users%2Fwilly%2Fxarray.git

bcm2835-camera: Convert context_map to XArray

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

diff --git a/drivers/staging/vc04_services/bcm2835-camera/mmal-vchiq.c b/drivers/staging/vc04_services/bcm2835-camera/mmal-vchiq.c
index 1c180ead4a20..e074b39ca8e7 100644
--- a/drivers/staging/vc04_services/bcm2835-camera/mmal-vchiq.c
+++ b/drivers/staging/vc04_services/bcm2835-camera/mmal-vchiq.c
@@ -111,7 +111,7 @@ struct vchiq_mmal_instance;
 struct mmal_msg_context {
 	struct vchiq_mmal_instance *instance;
 
-	/* Index in the context_map idr so that we can find the
+	/* Index in the context_map so that we can find the
 	 * mmal_msg_context again when servicing the VCHI reply.
 	 */
 	int handle;
@@ -163,9 +163,7 @@ struct vchiq_mmal_instance {
 	/* vmalloc page to receive scratch bulk xfers into */
 	void *bulk_scratch;
 
-	struct idr context_map;
-	/* protect accesses to context_map */
-	struct mutex context_map_lock;
+	struct xarray context_map;
 
 	/* component to use next */
 	int component_idx;
@@ -179,7 +177,7 @@ static struct mmal_msg_context *
 get_msg_context(struct vchiq_mmal_instance *instance)
 {
 	struct mmal_msg_context *msg_context;
-	int handle;
+	int err;
 
 	/* todo: should this be allocated from a pool to avoid kzalloc */
 	msg_context = kzalloc(sizeof(*msg_context), GFP_KERNEL);
@@ -187,30 +185,27 @@ get_msg_context(struct vchiq_mmal_instance *instance)
 	if (!msg_context)
 		return ERR_PTR(-ENOMEM);
 
-	/* Create an ID that will be passed along with our message so
+	msg_context->instance = instance;
+
+	/*
+	 * Create an ID that will be passed along with our message so
 	 * that when we service the VCHI reply, we can look up what
 	 * message is being replied to.
 	 */
-	mutex_lock(&instance->context_map_lock);
-	handle = idr_alloc(&instance->context_map, msg_context,
-			   0, 0, GFP_KERNEL);
-	mutex_unlock(&instance->context_map_lock);
-
-	if (handle < 0) {
+	err = xa_alloc(&instance->context_map, &msg_context->handle,
+			msg_context, xa_limit_32b, GFP_KERNEL);
+	if (err < 0) {
 		kfree(msg_context);
-		return ERR_PTR(handle);
+		return ERR_PTR(err);
 	}
 
-	msg_context->instance = instance;
-	msg_context->handle = handle;
-
 	return msg_context;
 }
 
 static struct mmal_msg_context *
 lookup_msg_context(struct vchiq_mmal_instance *instance, int handle)
 {
-	return idr_find(&instance->context_map, handle);
+	return xa_load(&instance->context_map, handle);
 }
 
 static void
@@ -218,9 +213,7 @@ release_msg_context(struct mmal_msg_context *msg_context)
 {
 	struct vchiq_mmal_instance *instance = msg_context->instance;
 
-	mutex_lock(&instance->context_map_lock);
-	idr_remove(&instance->context_map, msg_context->handle);
-	mutex_unlock(&instance->context_map_lock);
+	xa_erase(&instance->context_map, msg_context->handle);
 	kfree(msg_context);
 }
 
@@ -1803,8 +1796,6 @@ int vchiq_mmal_finalise(struct vchiq_mmal_instance *instance)
 
 	vfree(instance->bulk_scratch);
 
-	idr_destroy(&instance->context_map);
-
 	kfree(instance);
 
 	return status;
@@ -1858,8 +1849,7 @@ int vchiq_mmal_init(struct vchiq_mmal_instance **out_instance)
 
 	instance->bulk_scratch = vmalloc(PAGE_SIZE);
 
-	mutex_init(&instance->context_map_lock);
-	idr_init_base(&instance->context_map, 1);
+	xa_init_flags(&instance->context_map, XA_FLAGS_ALLOC1);
 
 	params.callback_param = instance;