From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     rafael@kernel.org, Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Subject: [PATCH 27/36] driver core: bus: constify bus_get()
Date:   Mon, 13 Mar 2023 19:29:09 +0100
Message-Id: <20230313182918.1312597-27-gregkh@linuxfoundation.org>
In-Reply-To: <20230313182918.1312597-1-gregkh@linuxfoundation.org>
References: <20230313182918.1312597-1-gregkh@linuxfoundation.org>
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It's funny to think about getting a reference count of a constant
structure pointer, but this locks into place the private data
"underneath" the struct bus_type() which is important to not go away
while we are working with the bus structure for some callbacks.

Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/base/bus.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/base/bus.c b/drivers/base/bus.c
index 8fea26c22521..84a21084d67d 100644
--- a/drivers/base/bus.c
+++ b/drivers/base/bus.c
@@ -84,7 +84,7 @@ static struct subsys_private *bus_to_subsys(const struct bus_type *bus)
 	return sp;
 }
 
-static struct bus_type *bus_get(struct bus_type *bus)
+static const struct bus_type *bus_get(const struct bus_type *bus)
 {
 	struct subsys_private *sp = bus_to_subsys(bus);
 
@@ -233,7 +233,7 @@ static const struct kset_uevent_ops bus_uevent_ops = {
 static ssize_t unbind_store(struct device_driver *drv, const char *buf,
 			    size_t count)
 {
-	struct bus_type *bus = bus_get(drv->bus);
+	const struct bus_type *bus = bus_get(drv->bus);
 	struct device *dev;
 	int err = -ENODEV;
 
@@ -256,7 +256,7 @@ static DRIVER_ATTR_IGNORE_LOCKDEP(unbind, 0200, NULL, unbind_store);
 static ssize_t bind_store(struct device_driver *drv, const char *buf,
 			  size_t count)
 {
-	struct bus_type *bus = bus_get(drv->bus);
+	const struct bus_type *bus = bus_get(drv->bus);
 	struct device *dev;
 	int err = -ENODEV;
 
-- 
2.39.2