92 lines
1.7 KiB
C
92 lines
1.7 KiB
C
|
// SPDX-License-Identifier: GPL-2.0-only
|
||
|
|
/*
|
||
|
|
* Intel MIC Platform Software Stack (MPSS)
|
||
|
|
*
|
||
|
|
* Copyright(c) 2013 Intel Corporation.
|
||
|
|
*
|
||
|
|
* Intel MIC User Space Tools.
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include "mpssd.h"
|
||
|
|
|
||
|
|
#define PAGE_SIZE 4096
|
||
|
|
|
||
|
|
char *
|
||
|
|
readsysfs(char *dir, char *entry)
|
||
|
|
{
|
||
|
|
char filename[PATH_MAX];
|
||
|
|
char value[PAGE_SIZE];
|
||
|
|
char *string = NULL;
|
||
|
|
int fd;
|
||
|
|
int len;
|
||
|
|
|
||
|
|
if (dir == NULL)
|
||
|
|
snprintf(filename, PATH_MAX, "%s/%s", MICSYSFSDIR, entry);
|
||
|
|
else
|
||
|
|
snprintf(filename, PATH_MAX,
|
||
|
|
"%s/%s/%s", MICSYSFSDIR, dir, entry);
|
||
|
|
|
||
|
|
fd = open(filename, O_RDONLY);
|
||
|
|
if (fd < 0) {
|
||
|
|
mpsslog("Failed to open sysfs entry '%s': %s\n",
|
||
|
|
filename, strerror(errno));
|
||
|
|
return NULL;
|
||
|
|
}
|
||
|
|
|
||
|
|
len = read(fd, value, sizeof(value));
|
||
|
|
if (len < 0) {
|
||
|
|
mpsslog("Failed to read sysfs entry '%s': %s\n",
|
||
|
|
filename, strerror(errno));
|
||
|
|
goto readsys_ret;
|
||
|
|
}
|
||
|
|
if (len == 0)
|
||
|
|
goto readsys_ret;
|
||
|
|
|
||
|
|
value[len - 1] = '\0';
|
||
|
|
|
||
|
|
string = malloc(strlen(value) + 1);
|
||
|
|
if (string)
|
||
|
|
strcpy(string, value);
|
||
|
|
|
||
|
|
readsys_ret:
|
||
|
|
close(fd);
|
||
|
|
return string;
|
||
|
|
}
|
||
|
|
|
||
|
|
int
|
||
|
|
setsysfs(char *dir, char *entry, char *value)
|
||
|
|
{
|
||
|
|
char filename[PATH_MAX];
|
||
|
|
char *oldvalue;
|
||
|
|
int fd, ret = 0;
|
||
|
|
|
||
|
|
if (dir == NULL)
|
||
|
|
snprintf(filename, PATH_MAX, "%s/%s", MICSYSFSDIR, entry);
|
||
|
|
else
|
||
|
|
snprintf(filename, PATH_MAX, "%s/%s/%s",
|
||
|
|
MICSYSFSDIR, dir, entry);
|
||
|
|
|
||
|
|
oldvalue = readsysfs(dir, entry);
|
||
|
|
|
||
|
|
fd = open(filename, O_RDWR);
|
||
|
|
if (fd < 0) {
|
||
|
|
ret = errno;
|
||
|
|
mpsslog("Failed to open sysfs entry '%s': %s\n",
|
||
|
|
filename, strerror(errno));
|
||
|
|
goto done;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (!oldvalue || strcmp(value, oldvalue)) {
|
||
|
|
if (write(fd, value, strlen(value)) < 0) {
|
||
|
|
ret = errno;
|
||
|
|
mpsslog("Failed to write new sysfs entry '%s': %s\n",
|
||
|
|
filename, strerror(errno));
|
||
|
|
}
|
||
|
|
}
|
||
|
|
close(fd);
|
||
|
|
done:
|
||
|
|
if (oldvalue)
|
||
|
|
free(oldvalue);
|
||
|
|
return ret;
|
||
|
|
}
|