driver core: bus: mark the struct bus_type for sysfs callbacks as constant

struct bus_type should never be modified in a sysfs callback as there is
nothing in the structure to modify, and frankly, the structure is almost
never used in a sysfs callback, so mark it as constant to allow struct
bus_type to be moved to read-only memory.

Cc: "David S. Miller" <davem@davemloft.net>
Cc: "James E.J. Bottomley" <jejb@linux.ibm.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Alexandre Bounine <alex.bou9@gmail.com>
Cc: Alison Schofield <alison.schofield@intel.com>
Cc: Ben Widawsky <bwidawsk@kernel.org>
Cc: Dexuan Cui <decui@microsoft.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Harald Freudenberger <freude@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Hu Haowen <src.res@email.cn>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Laurentiu Tudor <laurentiu.tudor@nxp.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Stuart Yoder <stuyoder@gmail.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Yanteng Si <siyanteng@loongson.cn>
Acked-by: Ilya Dryomov <idryomov@gmail.com> # rbd
Acked-by: Ira Weiny <ira.weiny@intel.com> # cxl
Reviewed-by: Alex Shi <alexs@kernel.org>
Acked-by: Iwona Winiarska <iwona.winiarska@intel.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>	# pci
Acked-by: Wei Liu <wei.liu@kernel.org>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com> # scsi
Link: https://lore.kernel.org/r/20230313182918.1312597-23-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 15 insertions, 19 deletions

diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index 5cb008b9700a..84ad3b17956f 100644
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -491,12 +491,12 @@ static bool single_major = true;
 module_param(single_major, bool, 0444);
 MODULE_PARM_DESC(single_major, "Use a single major number for all rbd devices (default: true)");
 
-static ssize_t add_store(struct bus_type *bus, const char *buf, size_t count);
-static ssize_t remove_store(struct bus_type *bus, const char *buf,
+static ssize_t add_store(const struct bus_type *bus, const char *buf, size_t count);
+static ssize_t remove_store(const struct bus_type *bus, const char *buf,
 			    size_t count);
-static ssize_t add_single_major_store(struct bus_type *bus, const char *buf,
+static ssize_t add_single_major_store(const struct bus_type *bus, const char *buf,
 				      size_t count);
-static ssize_t remove_single_major_store(struct bus_type *bus, const char *buf,
+static ssize_t remove_single_major_store(const struct bus_type *bus, const char *buf,
 					 size_t count);
 static int rbd_dev_image_probe(struct rbd_device *rbd_dev, int depth);
 
@@ -538,7 +538,7 @@ static bool rbd_is_lock_owner(struct rbd_device *rbd_dev)
 	return is_lock_owner;
 }
 
-static ssize_t supported_features_show(struct bus_type *bus, char *buf)
+static ssize_t supported_features_show(const struct bus_type *bus, char *buf)
 {
 	return sprintf(buf, "0x%llx\n", RBD_FEATURES_SUPPORTED);
 }
@@ -6967,9 +6967,7 @@ err_out_format:
 	return ret;
 }
 
-static ssize_t do_rbd_add(struct bus_type *bus,
-			  const char *buf,
-			  size_t count)
+static ssize_t do_rbd_add(const char *buf, size_t count)
 {
 	struct rbd_device *rbd_dev = NULL;
 	struct ceph_options *ceph_opts = NULL;
@@ -7081,18 +7079,18 @@ err_out_args:
 	goto out;
 }
 
-static ssize_t add_store(struct bus_type *bus, const char *buf, size_t count)
+static ssize_t add_store(const struct bus_type *bus, const char *buf, size_t count)
 {
 	if (single_major)
 		return -EINVAL;
 
-	return do_rbd_add(bus, buf, count);
+	return do_rbd_add(buf, count);
 }
 
-static ssize_t add_single_major_store(struct bus_type *bus, const char *buf,
+static ssize_t add_single_major_store(const struct bus_type *bus, const char *buf,
 				      size_t count)
 {
-	return do_rbd_add(bus, buf, count);
+	return do_rbd_add(buf, count);
 }
 
 static void rbd_dev_remove_parent(struct rbd_device *rbd_dev)
@@ -7122,9 +7120,7 @@ static void rbd_dev_remove_parent(struct rbd_device *rbd_dev)
 	}
 }
 
-static ssize_t do_rbd_remove(struct bus_type *bus,
-			     const char *buf,
-			     size_t count)
+static ssize_t do_rbd_remove(const char *buf, size_t count)
 {
 	struct rbd_device *rbd_dev = NULL;
 	struct list_head *tmp;
@@ -7196,18 +7192,18 @@ static ssize_t do_rbd_remove(struct bus_type *bus,
 	return count;
 }
 
-static ssize_t remove_store(struct bus_type *bus, const char *buf, size_t count)
+static ssize_t remove_store(const struct bus_type *bus, const char *buf, size_t count)
 {
 	if (single_major)
 		return -EINVAL;
 
-	return do_rbd_remove(bus, buf, count);
+	return do_rbd_remove(buf, count);
 }
 
-static ssize_t remove_single_major_store(struct bus_type *bus, const char *buf,
+static ssize_t remove_single_major_store(const struct bus_type *bus, const char *buf,
 					 size_t count)
 {
-	return do_rbd_remove(bus, buf, count);
+	return do_rbd_remove(buf, count);
 }
 
 /*