driver core: remove CONFIG_SYSFS_DEPRECATED and CONFIG_SYSFS_DEPRECATED_V2

CONFIG_SYSFS_DEPRECATED was added in commit 88a22c985e35
("CONFIG_SYSFS_DEPRECATED") in 2006 to allow systems with older versions
of some tools (i.e. Fedora 3's version of udev) to boot properly.  Four
years later, in 2010, the option was attempted to be removed as most of
userspace should have been fixed up properly by then, but some kernel
developers clung to those old systems and refused to update, so we added
CONFIG_SYSFS_DEPRECATED_V2 in commit e52eec13cd6b ("SYSFS: Allow boot
time switching between deprecated and modern sysfs layout") to allow
them to continue to boot properly, and we allowed a boot time parameter
to be used to switch back to the old format if needed.

Over time, the logic that was covered under these config options was
slowly removed from individual driver subsystems successfully, removed,
and the only thing that is now left in the kernel are some changes in
the block layer's representation in sysfs where real directories are
used instead of symlinks like normal.

Because the original changes were done to userspace tools in 2006, and
all distros that use those tools are long end-of-life, and older
non-udev-based systems do not care about the block layer's sysfs
representation, it is time to finally remove this old logic and the
config entries from the kernel.

Cc: Jonathan Corbet <corbet@lwn.net>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: linux-block@vger.kernel.org
Cc: linux-doc@vger.kernel.org
Acked-by: Jens Axboe <axboe@kernel.dk>
Link: https://lore.kernel.org/r/20230223073326.2073220-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 0 insertions, 37 deletions

diff --git a/drivers/base/core.c b/drivers/base/core.c
index 6878dfcbf0d6..ba11b51ce4ee 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -36,19 +36,6 @@
 #include "physical_location.h"
 #include "power/power.h"
 
-#ifdef CONFIG_SYSFS_DEPRECATED
-#ifdef CONFIG_SYSFS_DEPRECATED_V2
-long sysfs_deprecated = 1;
-#else
-long sysfs_deprecated = 0;
-#endif
-static int __init sysfs_deprecated_setup(char *arg)
-{
-	return kstrtol(arg, 10, &sysfs_deprecated);
-}
-early_param("sysfs.deprecated", sysfs_deprecated_setup);
-#endif
-
 /* Device links support. */
 static LIST_HEAD(deferred_sync);
 static unsigned int defer_sync_state_count = 1;
@@ -3137,15 +3124,6 @@ static struct kobject *get_device_parent(struct device *dev,
 		struct kobject *parent_kobj;
 		struct kobject *k;
 
-#ifdef CONFIG_BLOCK
-		/* block disks show up in /sys/block */
-		if (sysfs_deprecated && dev->class == &block_class) {
-			if (parent && parent->class == &block_class)
-				return &parent->kobj;
-			return &block_class.p->subsys.kobj;
-		}
-#endif
-
 		/*
 		 * If we have no parent, we live in "virtual".
 		 * Class-devices with a non class-device as parent, live
@@ -3324,12 +3302,6 @@ static int device_add_class_symlinks(struct device *dev)
 			goto out_subsys;
 	}
 
-#ifdef CONFIG_BLOCK
-	/* /sys/block has directories and does not need symlinks */
-	if (sysfs_deprecated && dev->class == &block_class)
-		return 0;
-#endif
-
 	/* link in the class directory pointing to the device */
 	error = sysfs_create_link(&dev->class->p->subsys.kobj,
 				  &dev->kobj, dev_name(dev));
@@ -3359,10 +3331,6 @@ static void device_remove_class_symlinks(struct device *dev)
 	if (dev->parent && device_is_not_partition(dev))
 		sysfs_remove_link(&dev->kobj, "device");
 	sysfs_remove_link(&dev->kobj, "subsystem");
-#ifdef CONFIG_BLOCK
-	if (sysfs_deprecated && dev->class == &block_class)
-		return;
-#endif
 	sysfs_delete_link(&dev->class->p->subsys.kobj, &dev->kobj, dev_name(dev));
 }
 
@@ -4652,11 +4620,6 @@ int device_change_owner(struct device *dev, kuid_t kuid, kgid_t kgid)
 	if (error)
 		goto out;
 
-#ifdef CONFIG_BLOCK
-	if (sysfs_deprecated && dev->class == &block_class)
-		goto out;
-#endif
-
 	/*
 	 * Change the owner of the symlink located in the class directory of
 	 * the device class associated with @dev which points to the actual