linux/arch/sparc/kernel/prom_common.c
Benjamin Herrenschmidt d25d86949b of: Fix locking vs. interrupts
The OF code uses irqsafe locks everywhere except in a handful of functions
for no obvious reasons. Since the conversion from the old rwlocks, this
now triggers lockdep warnings when used at interrupt time. At least one
driver (ibmvscsi) seems to be doing that from softirq context.

This converts the few non-irqsafe locks into irqsafe ones, making them
consistent with the rest of the code.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
2013-06-13 22:12:14 +01:00

163 lines
3.6 KiB
C

/* prom_common.c: OF device tree support common code.
*
* Paul Mackerras August 1996.
* Copyright (C) 1996-2005 Paul Mackerras.
*
* Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner.
* {engebret|bergner}@us.ibm.com
*
* Adapted for sparc by David S. Miller davem@davemloft.net
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/kernel.h>
#include <linux/export.h>
#include <linux/errno.h>
#include <linux/mutex.h>
#include <linux/slab.h>
#include <linux/of.h>
#include <linux/of_pdt.h>
#include <asm/prom.h>
#include <asm/oplib.h>
#include "prom.h"
struct device_node *of_console_device;
EXPORT_SYMBOL(of_console_device);
char *of_console_path;
EXPORT_SYMBOL(of_console_path);
char *of_console_options;
EXPORT_SYMBOL(of_console_options);
int of_getintprop_default(struct device_node *np, const char *name, int def)
{
struct property *prop;
int len;
prop = of_find_property(np, name, &len);
if (!prop || len != 4)
return def;
return *(int *) prop->value;
}
EXPORT_SYMBOL(of_getintprop_default);
DEFINE_MUTEX(of_set_property_mutex);
EXPORT_SYMBOL(of_set_property_mutex);
int of_set_property(struct device_node *dp, const char *name, void *val, int len)
{
struct property **prevp;
unsigned long flags;
void *new_val;
int err;
new_val = kmemdup(val, len, GFP_KERNEL);
if (!new_val)
return -ENOMEM;
err = -ENODEV;
mutex_lock(&of_set_property_mutex);
raw_spin_lock_irqsave(&devtree_lock, flags);
prevp = &dp->properties;
while (*prevp) {
struct property *prop = *prevp;
if (!strcasecmp(prop->name, name)) {
void *old_val = prop->value;
int ret;
ret = prom_setprop(dp->phandle, name, val, len);
err = -EINVAL;
if (ret >= 0) {
prop->value = new_val;
prop->length = len;
if (OF_IS_DYNAMIC(prop))
kfree(old_val);
OF_MARK_DYNAMIC(prop);
err = 0;
}
break;
}
prevp = &(*prevp)->next;
}
raw_spin_unlock_irqrestore(&devtree_lock, flags);
mutex_unlock(&of_set_property_mutex);
/* XXX Upate procfs if necessary... */
return err;
}
EXPORT_SYMBOL(of_set_property);
int of_find_in_proplist(const char *list, const char *match, int len)
{
while (len > 0) {
int l;
if (!strcmp(list, match))
return 1;
l = strlen(list) + 1;
list += l;
len -= l;
}
return 0;
}
EXPORT_SYMBOL(of_find_in_proplist);
/*
* SPARC32 and SPARC64's prom_nextprop() do things differently
* here, despite sharing the same interface. SPARC32 doesn't fill in 'buf',
* returning NULL on an error. SPARC64 fills in 'buf', but sets it to an
* empty string upon error.
*/
static int __init handle_nextprop_quirks(char *buf, const char *name)
{
if (!name || strlen(name) == 0)
return -1;
#ifdef CONFIG_SPARC32
strcpy(buf, name);
#endif
return 0;
}
static int __init prom_common_nextprop(phandle node, char *prev, char *buf)
{
const char *name;
buf[0] = '\0';
name = prom_nextprop(node, prev, buf);
return handle_nextprop_quirks(buf, name);
}
unsigned int prom_early_allocated __initdata;
static struct of_pdt_ops prom_sparc_ops __initdata = {
.nextprop = prom_common_nextprop,
.getproplen = prom_getproplen,
.getproperty = prom_getproperty,
.getchild = prom_getchild,
.getsibling = prom_getsibling,
};
void __init prom_build_devicetree(void)
{
of_pdt_build_devicetree(prom_root_node, &prom_sparc_ops);
of_console_init();
pr_info("PROM: Built device tree with %u bytes of memory.\n",
prom_early_allocated);
}