kernel-ark/arch/powerpc/kernel/of_device.c
Kay Sievers 7eff2e7a8b Driver core: change add_uevent_var to use a struct
This changes the uevent buffer functions to use a struct instead of a
long list of parameters. It does no longer require the caller to do the
proper buffer termination and size accounting, which is currently wrong
in some places. It fixes a known bug where parts of the uevent
environment are overwritten because of wrong index calculations.

Many thanks to Mathieu Desnoyers for finding bugs and improving the
error handling.

Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-10-12 14:51:01 -07:00

108 lines
2.5 KiB
C

#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/of.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
#include <linux/slab.h>
#include <asm/errno.h>
#include <asm/of_device.h>
ssize_t of_device_get_modalias(struct of_device *ofdev,
char *str, ssize_t len)
{
const char *compat;
int cplen, i;
ssize_t tsize, csize, repend;
/* Name & Type */
csize = snprintf(str, len, "of:N%sT%s",
ofdev->node->name, ofdev->node->type);
/* Get compatible property if any */
compat = of_get_property(ofdev->node, "compatible", &cplen);
if (!compat)
return csize;
/* Find true end (we tolerate multiple \0 at the end */
for (i=(cplen-1); i>=0 && !compat[i]; i--)
cplen--;
if (!cplen)
return csize;
cplen++;
/* Check space (need cplen+1 chars including final \0) */
tsize = csize + cplen;
repend = tsize;
if (csize>=len) /* @ the limit, all is already filled */
return tsize;
if (tsize>=len) { /* limit compat list */
cplen = len-csize-1;
repend = len;
}
/* Copy and do char replacement */
memcpy(&str[csize+1], compat, cplen);
for (i=csize; i<repend; i++) {
char c = str[i];
if (c=='\0')
str[i] = 'C';
else if (c==' ')
str[i] = '_';
}
return tsize;
}
int of_device_uevent(struct device *dev, struct kobj_uevent_env *env)
{
struct of_device *ofdev;
const char *compat;
int seen = 0, cplen, sl;
if (!dev)
return -ENODEV;
ofdev = to_of_device(dev);
if (add_uevent_var(env, "OF_NAME=%s", ofdev->node->name))
return -ENOMEM;
if (add_uevent_var(env, "OF_TYPE=%s", ofdev->node->type))
return -ENOMEM;
/* Since the compatible field can contain pretty much anything
* it's not really legal to split it out with commas. We split it
* up using a number of environment variables instead. */
compat = of_get_property(ofdev->node, "compatible", &cplen);
while (compat && *compat && cplen > 0) {
if (add_uevent_var(env, "OF_COMPATIBLE_%d=%s", seen, compat))
return -ENOMEM;
sl = strlen (compat) + 1;
compat += sl;
cplen -= sl;
seen++;
}
if (add_uevent_var(env, "OF_COMPATIBLE_N=%d", seen))
return -ENOMEM;
/* modalias is trickier, we add it in 2 steps */
if (add_uevent_var(env, "MODALIAS="))
return -ENOMEM;
sl = of_device_get_modalias(ofdev, &env->buf[env->buflen-1],
sizeof(env->buf) - env->buflen);
if (sl >= (sizeof(env->buf) - env->buflen))
return -ENOMEM;
env->buflen += sl;
return 0;
}
EXPORT_SYMBOL(of_device_uevent);
EXPORT_SYMBOL(of_device_get_modalias);