/*
* pSeries_reconfig.c - support for dynamic reconfiguration (including PCI
* Hotplug and Dynamic Logical Partitioning on RPA platforms).
*
* Copyright (C) 2005 Nathan Lynch
* Copyright (C) 2005 IBM Corporation
*
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License version
* 2 as published by the Free Software Foundation.
*/
#include <linux/kernel.h>
#include <linux/kref.h>
#include <linux/notifier.h>
#include <linux/proc_fs.h>
#include <asm/prom.h>
#include <asm/pSeries_reconfig.h>
#include <asm/uaccess.h>
/*
* Routines for "runtime" addition and removal of device tree nodes.
*/
#ifdef CONFIG_PROC_DEVICETREE
/*
* Add a node to /proc/device-tree.
*/
static void add_node_proc_entries(struct device_node *np)
{
struct proc_dir_entry *ent;
ent = proc_mkdir(strrchr(np->full_name, '/') + 1, np->parent->pde);
if (ent)
proc_device_tree_add_node(np, ent);
}
static void remove_node_proc_entries(struct device_node *np)
{
struct property *pp = np->properties;
struct device_node *parent = np->parent;
while (pp) {
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);
}
#else /* !CONFIG_PROC_DEVICETREE */
static void add_node_proc_entries(struct device_node *np)
{
return;
}
static void remove_node_proc_entries(struct device_node *np)
{
return;
}
#endif /* CONFIG_PROC_DEVICETREE */
/**
* derive_parent - basically like dirname(1)
* @path: the full_name of a node to be added to the tree
*
* Returns the node which should be the parent of the node
* described by path. E.g., for path = "/foo/bar", returns
* the node with full_name = "/foo".
*/
static struct device_node *derive_parent(const char *path)
{
struct device_node *parent = NULL;
char *parent_path = "/";
size_t parent_path_len = strrchr(path, '/') - path + 1;
/* reject if path is "/" */
if (!strcmp(path, "/"))
return ERR_PTR(-EINVAL);
if (strrchr(path, '/') != path) {
parent_path = kmalloc(parent_path_len, GFP_KERNEL);
if (!parent_path)
return ERR_PTR(-ENOMEM);
strlcpy(parent_path, path, parent_path_len);
}
parent = of_find_node_by_path(parent_path);
if (!parent)
return ERR_PTR(-EINVAL);
if (strcmp(parent_path, "/"))
kfree(parent_path);
return parent;
}
static struct notifier_block *pSeries_reconfig_chain;
int pSeries_reconfig_notifier_register(struct notifier_block *nb)
{
return notifier_chain_register(&pSeries_reconfig_chain, nb);
}
void pSeries_reconfig_notifier_unregister(struct notifier_block *nb)
{
notifier_chain_unregister(&pSeries_reconfig_chain, nb);
}
static int pSeries_reconfig_add_node(const char *path, struct property *proplist)
{
struct device_node *np;
int err = -ENOMEM;
np = kcalloc(1, sizeof(*np), GFP_KERNEL);
if (!np)
goto out_err;
np->full_name = kmalloc(strlen(path) + 1, GFP_KERNEL);
if (!np->full_name)
goto out_err;
strcpy(np->full_name, path);
np->properties = proplist;
OF_MARK_DYNAMIC(np);
kref_init(&np->kref);
np->parent = derive_parent(path);
if (IS_ERR(np->parent)) {
err = PTR_ERR(np->parent);
goto out_err;
}
err = notifier_call_chain(&pSeries_reconfig_chain,
PSERIES_RECONFIG_ADD, np);
if (err == NOTIFY_BAD) {
printk(KERN_ERR "Failed to add device node %s\n", path);
err = -ENOMEM; /* For now, safe to assume kmalloc failure */
goto out_err;
}
of_attach_node(np);
add_node_proc_entries(np);
of_node_put(np->parent);
return 0;
out_err:
if (np) {
of_node_put(np->parent);
kfree(np->full_name);
kfree(np);
}
return err;
}
static int pSeries_reconfig_remove_node(struct device_node *np)
{
struct device_node *parent, *child;
parent = of_get_parent(np);
if (!parent)
return -EINVAL;
if ((child = of_get_next_child(np, NULL))) {
of_node_put(child);
return -EBUSY;
}
remove_node_proc_entries(np);
notifier_call_chain(&pSeries_reconfig_chain,
PSERIES_RECONFIG_REMOVE, np);
of_detach_node(np);
of_node_put(parent);
of_node_put(np); /* Must decrement the refcount */
return 0;
}
/*
* /proc/ppc64/ofdt - yucky binary interface for adding and removing
* OF device nodes. Should be deprecated as soon as we get an
* in-kernel wrapper for the RTAS ibm,configure-connector call.
*/
static void release_prop_list(const struct property *prop)
{
struct property *next;
for (; prop; prop = next) {
next = prop->next;
kfree(prop->name);
kfree(prop->value);
kfree(prop);
}
}
/**
* parse_next_property - process the next property from raw input buffer
* @buf: input buffer, must be nul-terminated
* @end: end of the input buffer + 1, for validation
* @name: return value; set to property name in buf
* @length: return value; set to length of value
* @value: return value; set to the property value in buf
*
* Note that the caller must make copies of the name and value returned,
* this function does no allocation or copying of the data. Return value
* is set to the next name in buf, or NULL on error.
*/
static char * parse_next_property(char *buf, char *end, char **name, int *length,
unsigned char **value)
{
char *tmp;
*name = buf;
tmp = strchr(buf, ' ');
if (!tmp) {
printk(KERN_ERR "property parse failed in %s at line %d\n",
__FUNCTION__, __LINE__);
return NULL;
}
*tmp = '\0';
if (++tmp >= end) {
printk(KERN_ERR "property parse failed in %s at line %d\n",
__FUNCTION__, __LINE__);
return NULL;
}
/* now we're on the length */
*length = -1;
*length = simple_strtoul(tmp, &tmp, 10);
if (*length == -1) {
printk(KERN_ERR "property parse failed in %s at line %d\n",
__FUNCTION__, __LINE__);
return NULL;
}
if (*tmp != ' ' || ++tmp >= end) {
printk(KERN_ERR "property parse failed in %s at line %d\n",
__FUNCTION__, __LINE__);
return NULL;
}
/* now we're on the value */
*value = tmp;
tmp += *length;
if (tmp > end) {
printk(KERN_ERR "property parse failed in %s at line %d\n",
__FUNCTION__, __LINE__);
return NULL;
}
else if (tmp < end && *tmp != ' ' && *tmp != '\0') {
printk(KERN_ERR "property parse failed in %s at line %d\n",
__FUNCTION__, __LINE__);
return NULL;
}
tmp++;
/* and now we should be on the next name, or the end */
return tmp;
}
static struct property *new_property(const char *name, const int length,
const unsigned char *value, struct property *last)
{
struct property *new = kmalloc(sizeof(*new), GFP_KERNEL);
if (!new)
return NULL;
memset(new, 0, sizeof(*new));
if (!(new->name = kmalloc(strlen(name) + 1, GFP_KERNEL)))
goto cleanup;
if (!(new->value = kmalloc(length + 1, GFP_KERNEL)))
goto cleanup;
strcpy(new->name, name);
memcpy(new->value, value, length);
*(((char *)new->value) + length) = 0;
new->length = length;
new->next = last;
return new;
cleanup:
if (new->name)
kfree(new->name);
if (new->value)
kfree(new->value);
kfree(new);
return NULL;
}
static int do_add_node(char *buf, size_t bufsize)
{
char *path, *end, *name;
struct device_node *np;
struct property *prop = NULL;
unsigned char* value;
int length, rv = 0;
end = buf + bufsize;
path = buf;
buf = strchr(buf, ' ');
if (!buf)
return -EINVAL;
*buf = '\0';
buf++;
if ((np = of_find_node_by_path(path))) {
of_node_put(np);
return -EINVAL;
}
/* rv = build_prop_list(tmp, bufsize - (tmp - buf), &proplist); */
while (buf < end &&
(buf = parse_next_property(buf, end, &name, &length, &value))) {
struct property *last = prop;
prop = new_property(name, length, value, last);
if (!prop) {
rv = -ENOMEM;
prop = last;
goto out;
}
}
if (!buf) {
rv = -EINVAL;
goto out;
}
rv = pSeries_reconfig_add_node(path, prop);
out:
if (rv)
release_prop_list(prop);
return rv;
}
static int do_remove_node(char *buf)
{
struct device_node *node;
int rv = -ENODEV;
if ((node = of_find_node_by_path(buf)))
rv = pSeries_reconfig_remove_node(node);
of_node_put(node);
return rv;
}
/**
* ofdt_write - perform operations on the Open Firmware device tree
*
* @file: not used
* @buf: command and arguments
* @count: size of the command buffer
* @off: not used
*
* Operations supported at this time are addition and removal of
* whole nodes along with their properties. Operations on individual
* properties are not implemented (yet).
*/
static ssize_t ofdt_write(struct file *file, const char __user *buf, size_t count,
loff_t *off)
{
int rv = 0;
char *kbuf;
char *tmp;
if (!(kbuf = kmalloc(count + 1, GFP_KERNEL))) {
rv = -ENOMEM;
goto out;
}
if (copy_from_user(kbuf, buf, count)) {
rv = -EFAULT;
goto out;
}
kbuf[count] = '\0';
tmp = strchr(kbuf, ' ');
if (!tmp) {
rv = -EINVAL;
goto out;
}
*tmp = '\0';
tmp++;
if (!strcmp(kbuf, "add_node"))
rv = do_add_node(tmp, count - (tmp - kbuf));
else if (!strcmp(kbuf, "remove_node"))
rv = do_remove_node(tmp);
else
rv = -EINVAL;
out:
kfree(kbuf);
return rv ? rv : count;
}
static struct file_operations ofdt_fops = {
.write = ofdt_write
};
/* create /proc/ppc64/ofdt write-only by root */
static int proc_ppc64_create_ofdt(void)
{
struct proc_dir_entry *ent;
if (!(systemcfg->platform & PLATFORM_PSERIES))
return 0;
ent = create_proc_entry("ppc64/ofdt", S_IWUSR, NULL);
if (ent) {
ent->nlink = 1;
ent->data = NULL;
ent->size = 0;
ent->proc_fops = &ofdt_fops;
}
return 0;
}
__initcall(proc_ppc64_create_ofdt);
