of: remove /proc/device-tree

The same data is now available in sysfs, so we can remove the code
that exports it in /proc and replace it with a symlink to the sysfs
version.

Tested on versatile qemu model and mpc5200 eval board. More testing
would be appreciated.

v5: Fixed up conflicts with mainline changes

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Cc: Pantelis Antoniou <panto@antoniou-consulting.com>

drivers/of/Kconfig

@@ -7,14 +7,6 @@ config OF
 menu "Device Tree and Open Firmware support"
 	depends on OF
 
-config PROC_DEVICETREE
-	bool "Support for device tree in /proc"
-	depends on PROC_FS && !SPARC
-	help
-	  This option adds a device-tree directory under /proc which contains
-	  an image of the device tree that the kernel copies from Open
-	  Firmware or other boot firmware. If unsure, say Y here.
-
 config OF_SELFTEST
 	bool "Device Tree Runtime self tests"
 	depends on OF_IRQ

drivers/of/base.c

@@ -281,11 +281,9 @@ static int __init of_init(void)
 		__of_node_add(np);
 	mutex_unlock(&of_aliases_mutex);
 
-#if !defined(CONFIG_PROC_DEVICETREE)
-	/* Symlink to the new tree when PROC_DEVICETREE is disabled */
+	/* Symlink in /proc as required by userspace ABI */
 	if (of_allnodes)
 		proc_symlink("device-tree", NULL, "/sys/firmware/devicetree/base");
-#endif /* CONFIG_PROC_DEVICETREE */
 
 	return 0;
 }
@@ -1690,12 +1688,6 @@ int of_add_property(struct device_node *np, struct property *prop)
 
 	__of_add_property_sysfs(np, prop);
 
-#ifdef CONFIG_PROC_DEVICETREE
-	/* try to add to proc as well if it was initialized */
-	if (!rc && np->pde)
-		proc_device_tree_add_prop(np->pde, prop);
-#endif /* CONFIG_PROC_DEVICETREE */
-
 	return rc;
 }
 
@@ -1742,12 +1734,6 @@ int of_remove_property(struct device_node *np, struct property *prop)
 
 	sysfs_remove_bin_file(&np->kobj, &prop->attr);
 
-#ifdef CONFIG_PROC_DEVICETREE
-	/* try to remove the proc node as well */
-	if (np->pde)
-		proc_device_tree_remove_prop(np->pde, prop);
-#endif /* CONFIG_PROC_DEVICETREE */
-
 	return 0;
 }
 
@@ -1803,12 +1789,6 @@ int of_update_property(struct device_node *np, struct property *newprop)
 	if (!found)
 		return -ENODEV;
 
-#ifdef CONFIG_PROC_DEVICETREE
-	/* try to add to proc as well if it was initialized */
-	if (np->pde)
-		proc_device_tree_update_prop(np->pde, newprop, oldprop);
-#endif /* CONFIG_PROC_DEVICETREE */
-
 	return 0;
 }
 
@@ -1843,22 +1823,6 @@ int of_reconfig_notify(unsigned long action, void *p)
 	return notifier_to_errno(rc);
 }
 
-#ifdef CONFIG_PROC_DEVICETREE
-static void of_add_proc_dt_entry(struct device_node *dn)
-{
-	struct proc_dir_entry *ent;
-
-	ent = proc_mkdir(strrchr(dn->full_name, '/') + 1, dn->parent->pde);
-	if (ent)
-		proc_device_tree_add_node(dn, ent);
-}
-#else
-static void of_add_proc_dt_entry(struct device_node *dn)
-{
-	return;
-}
-#endif
-
 /**
  * of_attach_node - Plug a device node into the tree and global list.
  */
@@ -1880,22 +1844,9 @@ int of_attach_node(struct device_node *np)
 	raw_spin_unlock_irqrestore(&devtree_lock, flags);
 
 	of_node_add(np);
-	of_add_proc_dt_entry(np);
 	return 0;
 }
 
-#ifdef CONFIG_PROC_DEVICETREE
-static void of_remove_proc_dt_entry(struct device_node *dn)
-{
-	proc_remove(dn->pde);
-}
-#else
-static void of_remove_proc_dt_entry(struct device_node *dn)
-{
-	return;
-}
-#endif
-
 /**
  * of_detach_node - "Unplug" a node from the device tree.
  *
@@ -1951,7 +1902,6 @@ int of_detach_node(struct device_node *np)
 	of_node_set_flag(np, OF_DETACHED);
 	raw_spin_unlock_irqrestore(&devtree_lock, flags);
 
-	of_remove_proc_dt_entry(np);
 	of_node_remove(np);
 	return rc;
 }

fs/proc/Makefile

@@ -27,6 +27,5 @@ proc-$(CONFIG_PROC_SYSCTL)	+= proc_sysctl.o
 proc-$(CONFIG_NET)		+= proc_net.o
 proc-$(CONFIG_PROC_KCORE)	+= kcore.o
 proc-$(CONFIG_PROC_VMCORE)	+= vmcore.o
-proc-$(CONFIG_PROC_DEVICETREE)	+= proc_devtree.o
 proc-$(CONFIG_PRINTK)	+= kmsg.o
 proc-$(CONFIG_PROC_PAGE_MONITOR)	+= page.o

fs/proc/internal.h

@@ -210,13 +210,6 @@ extern struct inode *proc_get_inode(struct super_block *, struct proc_dir_entry
 extern int proc_fill_super(struct super_block *);
 extern void proc_entry_rundown(struct proc_dir_entry *);
 
-/*
- * proc_devtree.c
- */
-#ifdef CONFIG_PROC_DEVICETREE
-extern void proc_device_tree_init(void);
-#endif
-
 /*
  * proc_namespaces.c
  */

fs/proc/root.c

@@ -183,9 +183,6 @@ void __init proc_root_init(void)
 	proc_mkdir("openprom", NULL);
 #endif
 	proc_tty_init();
-#ifdef CONFIG_PROC_DEVICETREE
-	proc_device_tree_init();
-#endif
 	proc_mkdir("bus", NULL);
 	proc_sys_init();
 }