[PATCH] ppc32/ppc64: cleanup /proc/device-tree
Benjamin Herrenschmidt
benh at kernel.crashing.org
Wed Jun 1 17:07:27 EST 2005
Hi !
This patch cleans up the /proc/device-tree representation of the Open
Firmware device-tree on ppc and ppc64. It does the following things:
- Workaround an issue in some Apple device-trees where a property may
exist with the same name as a child node of the parent. We now simply
"drop" the property instead of creating duplicate entries in /proc with
random result...
- Do not try to chop off the "@0" at the end of a node name whose unit
address is 0. This is not useful, inconsistent, and the code was buggy
and didn't always work anyway.
- Do not create symlinks for the short name and unit address parts of a
ndoe. These were never really used, bloated the memory footprint of the
device-tree with useless struct proc_dir_entry and their matching dentry
and inode cache bloat.
This results in smaller code, smaller memory footprint, and a more
accurate view of the tree presented to userland.
Signed-off-by: Benjamin Herrenschmidt <benh at kernel.crashing.org>
Index: linux-work/fs/proc/proc_devtree.c
===================================================================
--- linux-work.orig/fs/proc/proc_devtree.c 2005-06-01 16:18:51.000000000 +1000
+++ linux-work/fs/proc/proc_devtree.c 2005-06-01 16:47:35.000000000 +1000
@@ -12,15 +12,8 @@
#include <asm/uaccess.h>
#ifndef HAVE_ARCH_DEVTREE_FIXUPS
-static inline void set_node_proc_entry(struct device_node *np, struct proc_dir_entry *de)
-{
-}
-
-static void inline set_node_name_link(struct device_node *np, struct proc_dir_entry *de)
-{
-}
-
-static void inline set_node_addr_link(struct device_node *np, struct proc_dir_entry *de)
+static inline void set_node_proc_entry(struct device_node *np,
+ struct proc_dir_entry *de)
{
}
#endif
@@ -58,89 +51,67 @@
/*
* Process a node, adding entries for its children and its properties.
*/
-void proc_device_tree_add_node(struct device_node *np, struct proc_dir_entry *de)
+void proc_device_tree_add_node(struct device_node *np,
+ struct proc_dir_entry *de)
{
struct property *pp;
struct proc_dir_entry *ent;
- struct device_node *child, *sib;
- const char *p, *at;
- int l;
- struct proc_dir_entry *list, **lastp, *al;
+ struct device_node *child;
+ struct proc_dir_entry *list = NULL, **lastp;
+ const char *p;
set_node_proc_entry(np, de);
lastp = &list;
- for (pp = np->properties; pp != 0; pp = pp->next) {
- /*
- * Unfortunately proc_register puts each new entry
- * at the beginning of the list. So we rearrange them.
- */
- ent = create_proc_read_entry(pp->name, strncmp(pp->name, "security-", 9) ?
- S_IRUGO : S_IRUSR, de, property_read_proc, pp);
- if (ent == 0)
- break;
- if (!strncmp(pp->name, "security-", 9))
- ent->size = 0; /* don't leak number of password chars */
- else
- ent->size = pp->length;
- *lastp = ent;
- lastp = &ent->next;
- }
- child = NULL;
- while ((child = of_get_next_child(np, child))) {
+ for (child = NULL; (child = of_get_next_child(np, child));) {
p = strrchr(child->full_name, '/');
if (!p)
p = child->full_name;
else
++p;
- /* chop off '@0' if the name ends with that */
- l = strlen(p);
- if (l > 2 && p[l-2] == '@' && p[l-1] == '0')
- l -= 2;
ent = proc_mkdir(p, de);
if (ent == 0)
break;
*lastp = ent;
+ ent->next = NULL;
lastp = &ent->next;
proc_device_tree_add_node(child, ent);
-
- /*
- * If we left the address part on the name, consider
- * adding symlinks from the name and address parts.
- */
- if (p[l] != 0 || (at = strchr(p, '@')) == 0)
- continue;
-
+ }
+ of_node_put(child);
+ for (pp = np->properties; pp != 0; pp = pp->next) {
/*
- * If this is the first node with a given name property,
- * add a symlink with the name property as its name.
+ * Yet another Apple device-tree bogosity: on some machines,
+ * they have properties & nodes with the same name. Those
+ * properties are quite unimportant for us though, thus we
+ * simply "skip" them here, but we do have to check.
*/
- sib = NULL;
- while ((sib = of_get_next_child(np, sib)) && sib != child)
- if (sib->name && strcmp(sib->name, child->name) == 0)
- break;
- if (sib == child && strncmp(p, child->name, l) != 0) {
- al = proc_symlink(child->name, de, ent->name);
- if (al == 0) {
- of_node_put(sib);
+ for (ent = list; ent != NULL; ent = ent->next)
+ if (!strcmp(ent->name, pp->name))
break;
- }
- set_node_name_link(child, al);
- *lastp = al;
- lastp = &al->next;
+ if (ent != NULL) {
+ printk(KERN_WARNING "device-tree: property \"%s\" name"
+ " conflicts with node in %s\n", pp->name,
+ np->full_name);
+ continue;
}
- of_node_put(sib);
+
/*
- * Add another directory with the @address part as its name.
+ * Unfortunately proc_register puts each new entry
+ * at the beginning of the list. So we rearrange them.
*/
- al = proc_symlink(at, de, ent->name);
- if (al == 0)
+ ent = create_proc_read_entry(pp->name,
+ strncmp(pp->name, "security-", 9)
+ ? S_IRUGO : S_IRUSR, de,
+ property_read_proc, pp);
+ if (ent == 0)
break;
- set_node_addr_link(child, al);
- *lastp = al;
- lastp = &al->next;
+ if (!strncmp(pp->name, "security-", 9))
+ ent->size = 0; /* don't leak number of password chars */
+ else
+ ent->size = pp->length;
+ ent->next = NULL;
+ *lastp = ent;
+ lastp = &ent->next;
}
- of_node_put(child);
- *lastp = NULL;
de->subdir = list;
}
Index: linux-work/include/asm-ppc64/prom.h
===================================================================
--- linux-work.orig/include/asm-ppc64/prom.h 2005-06-01 16:18:51.000000000 +1000
+++ linux-work/include/asm-ppc64/prom.h 2005-06-01 16:30:30.000000000 +1000
@@ -147,9 +147,7 @@
struct device_node *sibling;
struct device_node *next; /* next device of same type */
struct device_node *allnext; /* next in list of all nodes */
- struct proc_dir_entry *pde; /* this node's proc directory */
- struct proc_dir_entry *name_link; /* name symlink */
- struct proc_dir_entry *addr_link; /* addr symlink */
+ struct proc_dir_entry *pde; /* this node's proc directory */
struct kref kref;
unsigned long _flags;
};
@@ -174,15 +172,6 @@
dn->pde = de;
}
-static void inline set_node_name_link(struct device_node *dn, struct proc_dir_entry *de)
-{
- dn->name_link = de;
-}
-
-static void inline set_node_addr_link(struct device_node *dn, struct proc_dir_entry *de)
-{
- dn->addr_link = de;
-}
/* OBSOLETE: Old stlye node lookup */
extern struct device_node *find_devices(const char *name);
Index: linux-work/arch/ppc64/kernel/pSeries_reconfig.c
===================================================================
--- linux-work.orig/arch/ppc64/kernel/pSeries_reconfig.c 2005-06-01 16:18:51.000000000 +1000
+++ linux-work/arch/ppc64/kernel/pSeries_reconfig.c 2005-06-01 16:30:30.000000000 +1000
@@ -47,14 +47,6 @@
remove_proc_entry(pp->name, np->pde);
pp = pp->next;
}
-
- /* Assuming that symlinks have the same parent directory as
- * np->pde.
- */
- if (np->name_link)
- remove_proc_entry(np->name_link->name, parent->pde);
- if (np->addr_link)
- remove_proc_entry(np->addr_link->name, parent->pde);
if (np->pde)
remove_proc_entry(np->pde->name, parent->pde);
}
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