Merge tag 'driver-core-6.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core and debugfs updates from Greg KH:
 "Here is the big set of driver core and debugfs updates for 6.14-rc1.

  Included in here is a bunch of driver core, PCI, OF, and platform rust
  bindings (all acked by the different subsystem maintainers), hence the
  merge conflict with the rust tree, and some driver core api updates to
  mark things as const, which will also require some fixups due to new
  stuff coming in through other trees in this merge window.

  There are also a bunch of debugfs updates from Al, and there is at
  least one user that does have a regression with these, but Al is
  working on tracking down the fix for it. In my use (and everyone
  else's linux-next use), it does not seem like a big issue at the
  moment.

  Here's a short list of the things in here:

   - driver core rust bindings for PCI, platform, OF, and some i/o
     functions.

     We are almost at the "write a real driver in rust" stage now,
     depending on what you want to do.

   - misc device rust bindings and a sample driver to show how to use
     them

   - debugfs cleanups in the fs as well as the users of the fs api for
     places where drivers got it wrong or were unnecessarily doing
     things in complex ways.

   - driver core const work, making more of the api take const * for
     different parameters to make the rust bindings easier overall.

   - other small fixes and updates

  All of these have been in linux-next with all of the aforementioned
  merge conflicts, and the one debugfs issue, which looks to be resolved
  "soon""

* tag 'driver-core-6.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (95 commits)
  rust: device: Use as_char_ptr() to avoid explicit cast
  rust: device: Replace CString with CStr in property_present()
  devcoredump: Constify 'struct bin_attribute'
  devcoredump: Define 'struct bin_attribute' through macro
  rust: device: Add property_present()
  saner replacement for debugfs_rename()
  orangefs-debugfs: don't mess with ->d_name
  octeontx2: don't mess with ->d_parent or ->d_parent->d_name
  arm_scmi: don't mess with ->d_parent->d_name
  slub: don't mess with ->d_name
  sof-client-ipc-flood-test: don't mess with ->d_name
  qat: don't mess with ->d_name
  xhci: don't mess with ->d_iname
  mtu3: don't mess wiht ->d_iname
  greybus/camera - stop messing with ->d_iname
  mediatek: stop messing with ->d_iname
  netdevsim: don't embed file_operations into your structs
  b43legacy: make use of debugfs_get_aux()
  b43: stop embedding struct file_operations into their objects
  carl9170: stop embedding file_operations into their objects
  ...

Author: torvalds

Documentation/filesystems/debugfs.rst

@@ -211,18 +211,16 @@ seq_file content.
 
 There are a couple of other directory-oriented helper functions::
 
-    struct dentry *debugfs_rename(struct dentry *old_dir,
-    				  struct dentry *old_dentry,
-		                  struct dentry *new_dir,
-				  const char *new_name);
+    struct dentry *debugfs_change_name(struct dentry *dentry,
+					  const char *fmt, ...);
 
     struct dentry *debugfs_create_symlink(const char *name,
                                           struct dentry *parent,
 				      	  const char *target);
 
-A call to debugfs_rename() will give a new name to an existing debugfs
-file, possibly in a different directory.  The new_name must not exist prior
-to the call; the return value is old_dentry with updated information.
+A call to debugfs_change_name() will give a new name to an existing debugfs
+file, always in the same directory.  The new_name must not exist prior
+to the call; the return value is 0 on success and -E... on failuer.
 Symbolic links can be created with debugfs_create_symlink().
 
 There is one important thing that all debugfs users must take into account:

Documentation/userspace-api/ioctl/ioctl-number.rst

@@ -312,6 +312,7 @@ Code  Seq#    Include File                                           Comments
                                                                      <mailto:[email protected]>
 'z'   10-4F  drivers/s390/crypto/zcrypt_api.h                        conflict!
 '|'   00-7F  linux/media.h
+'|'   80-9F  samples/                                                Any sample and example drivers
 0x80  00-1F  linux/fb.h
 0x81  00-1F  linux/vduse.h
 0x89  00-06  arch/x86/include/asm/sockios.h

MAINTAINERS

@@ -5366,6 +5366,7 @@ T:	git git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git
 F:	drivers/char/
 F:	drivers/misc/
 F:	include/linux/miscdevice.h
+F:	samples/rust/rust_misc_device.rs
 X:	drivers/char/agp/
 X:	drivers/char/hw_random/
 X:	drivers/char/ipmi/
@@ -7091,6 +7092,7 @@ F:	include/linux/component.h
 DRIVER CORE, KOBJECTS, DEBUGFS AND SYSFS
 M:	Greg Kroah-Hartman <[email protected]>
 R:	"Rafael J. Wysocki" <[email protected]>
+R:	Danilo Krummrich <[email protected]>
 S:	Supported
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core.git
 F:	Documentation/core-api/kobject.rst
@@ -7101,8 +7103,14 @@ F:	include/linux/debugfs.h
 F:	include/linux/fwnode.h
 F:	include/linux/kobj*
 F:	include/linux/property.h
+F:	include/linux/sysfs.h
 F:	lib/kobj*
 F:	rust/kernel/device.rs
+F:	rust/kernel/device_id.rs
+F:	rust/kernel/devres.rs
+F:	rust/kernel/driver.rs
+F:	rust/kernel/platform.rs
+F:	samples/rust/rust_driver_platform.rs
 
 DRIVERS FOR OMAP ADAPTIVE VOLTAGE SCALING (AVS)
 M:	Nishanth Menon <[email protected]>
@@ -17632,6 +17640,7 @@ T:	git git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux.git
 F:	Documentation/ABI/testing/sysfs-firmware-ofw
 F:	drivers/of/
 F:	include/linux/of*.h
+F:	rust/kernel/of.rs
 F:	scripts/dtc/
 F:	tools/testing/selftests/dt/
 K:	of_overlay_notifier_
@@ -18232,6 +18241,8 @@ F:	include/asm-generic/pci*
 F:	include/linux/of_pci.h
 F:	include/linux/pci*
 F:	include/uapi/linux/pci*
+F:	rust/kernel/pci.rs
+F:	samples/rust/rust_driver_pci.rs
 
 PCIE BANDWIDTH CONTROLLER
 M:	Ilpo Järvinen <[email protected]>
@@ -19830,6 +19841,7 @@ T:	git git://git.kernel.org/pub/scm/linux/kernel/git/rcu/linux.git rcu/dev
 F:	Documentation/RCU/
 F:	include/linux/rcu*
 F:	kernel/rcu/
+F:	rust/kernel/sync/rcu.rs
 X:	Documentation/RCU/torture.rst
 X:	include/linux/srcu*.h
 X:	kernel/rcu/srcu*.c

arch/arm/include/asm/ecard.h

@@ -195,7 +195,7 @@ void __iomem *ecardm_iomap(struct expansion_card *ec, unsigned int res,
 			   unsigned long offset, unsigned long maxsize);
 #define ecardm_iounmap(__ec, __addr)	devm_iounmap(&(__ec)->dev, __addr)
 
-extern struct bus_type ecard_bus_type;
+extern const struct bus_type ecard_bus_type;
 
 #define ECARD_DEV(_d)	container_of((_d), struct expansion_card, dev)
 

arch/arm/mach-rpc/ecard.c

@@ -1124,7 +1124,7 @@ static int ecard_match(struct device *_dev, const struct device_driver *_drv)
 	return ret;
 }
 
-struct bus_type ecard_bus_type = {
+const struct bus_type ecard_bus_type = {
 	.name		= "ecard",
 	.dev_groups	= ecard_dev_groups,
 	.match		= ecard_match,

arch/powerpc/platforms/powernv/opal.c

@@ -815,7 +815,7 @@ static int opal_add_one_export(struct kobject *parent, const char *export_name,
 	sysfs_bin_attr_init(attr);
 	attr->attr.name = name;
 	attr->attr.mode = 0400;
-	attr->read = sysfs_bin_attr_simple_read;
+	attr->read_new = sysfs_bin_attr_simple_read;
 	attr->private = __va(vals[0]);
 	attr->size = vals[1];
 

arch/sparc/kernel/vio.c

@@ -419,13 +419,13 @@ struct vio_remove_node_data {
 	u64 node;
 };
 
-static int vio_md_node_match(struct device *dev, void *arg)
+static int vio_md_node_match(struct device *dev, const void *arg)
 {
 	struct vio_dev *vdev = to_vio_dev(dev);
-	struct vio_remove_node_data *node_data;
+	const struct vio_remove_node_data *node_data;
 	u64 node;
 
-	node_data = (struct vio_remove_node_data *)arg;
+	node_data = (const struct vio_remove_node_data *)arg;
 
 	node = vio_vdev_node(node_data->hp, vdev);
 

block/blk-cgroup.c

@@ -1138,6 +1138,7 @@ static void blkcg_fill_root_iostats(void)
 		blkg_iostat_set(&blkg->iostat.cur, &tmp);
 		u64_stats_update_end_irqrestore(&blkg->iostat.sync, flags);
 	}
+	class_dev_iter_exit(&iter);
 }
 
 static void blkcg_print_one_stat(struct blkcg_gq *blkg, struct seq_file *s)

drivers/base/bus.c

@@ -354,7 +354,7 @@ static struct device *next_device(struct klist_iter *i)
  * count in the supplied callback.
  */
 int bus_for_each_dev(const struct bus_type *bus, struct device *start,
-		     void *data, int (*fn)(struct device *, void *))
+		     void *data, device_iter_t fn)
 {
 	struct subsys_private *sp = bus_to_subsys(bus);
 	struct klist_iter i;
@@ -402,9 +402,12 @@ struct device *bus_find_device(const struct bus_type *bus,
 
 	klist_iter_init_node(&sp->klist_devices, &i,
 			     (start ? &start->p->knode_bus : NULL));
-	while ((dev = next_device(&i)))
-		if (match(dev, data) && get_device(dev))
+	while ((dev = next_device(&i))) {
+		if (match(dev, data)) {
+			get_device(dev);
 			break;
+		}
+	}
 	klist_iter_exit(&i);
 	subsys_put(sp);
 	return dev;

drivers/base/class.c

@@ -323,8 +323,12 @@ void class_dev_iter_init(struct class_dev_iter *iter, const struct class *class,
 	struct subsys_private *sp = class_to_subsys(class);
 	struct klist_node *start_knode = NULL;
 
-	if (!sp)
+	memset(iter, 0, sizeof(*iter));
+	if (!sp) {
+		pr_crit("%s: class %p was not registered yet\n",
+			__func__, class);
 		return;
+	}
 
 	if (start)
 		start_knode = &start->p->knode_class;
@@ -351,6 +355,9 @@ struct device *class_dev_iter_next(struct class_dev_iter *iter)
 	struct klist_node *knode;
 	struct device *dev;
 
+	if (!iter->sp)
+		return NULL;
+
 	while (1) {
 		knode = klist_next(&iter->ki);
 		if (!knode)
@@ -395,7 +402,7 @@ EXPORT_SYMBOL_GPL(class_dev_iter_exit);
  * code.  There's no locking restriction.
  */
 int class_for_each_device(const struct class *class, const struct device *start,
-			  void *data, int (*fn)(struct device *, void *))
+			  void *data, device_iter_t fn)
 {
 	struct subsys_private *sp = class_to_subsys(class);
 	struct class_dev_iter iter;
@@ -594,30 +601,10 @@ EXPORT_SYMBOL_GPL(class_compat_unregister);
  *			      a bus device
  * @cls: the compatibility class
  * @dev: the target bus device
- * @device_link: an optional device to which a "device" link should be created
  */
-int class_compat_create_link(struct class_compat *cls, struct device *dev,
-			     struct device *device_link)
+int class_compat_create_link(struct class_compat *cls, struct device *dev)
 {
-	int error;
-
-	error = sysfs_create_link(cls->kobj, &dev->kobj, dev_name(dev));
-	if (error)
-		return error;
-
-	/*
-	 * Optionally add a "device" link (typically to the parent), as a
-	 * class device would have one and we want to provide as much
-	 * backwards compatibility as possible.
-	 */
-	if (device_link) {
-		error = sysfs_create_link(&dev->kobj, &device_link->kobj,
-					  "device");
-		if (error)
-			sysfs_remove_link(cls->kobj, dev_name(dev));
-	}
-
-	return error;
+	return sysfs_create_link(cls->kobj, &dev->kobj, dev_name(dev));
 }
 EXPORT_SYMBOL_GPL(class_compat_create_link);
 
@@ -626,14 +613,9 @@ EXPORT_SYMBOL_GPL(class_compat_create_link);
  *			      a bus device
  * @cls: the compatibility class
  * @dev: the target bus device
- * @device_link: an optional device to which a "device" link was previously
- * 		 created
  */
-void class_compat_remove_link(struct class_compat *cls, struct device *dev,
-			      struct device *device_link)
+void class_compat_remove_link(struct class_compat *cls, struct device *dev)
 {
-	if (device_link)
-		sysfs_remove_link(&dev->kobj, "device");
 	sysfs_remove_link(cls->kobj, dev_name(dev));
 }
 EXPORT_SYMBOL_GPL(class_compat_remove_link);