Files
s390-tools/ipl_tools/ccw.c
Jan Polensky 6f53d7d3cd ipl_tools: Remove unused header
Optimize dependency management by reducing header inclusions. This
reduces hidden dependencies, improves modularity, and enhances
compilation performance.

Signed-off-by: Jan Polensky <japo@linux.ibm.com>
Reviewed-by: Jan Höppner <hoeppner@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
2025-04-07 17:42:18 +02:00

117 lines
2.8 KiB
C

/*
* ipl_tools - Linux for System z reipl and shutdown tools
*
* CCW device functions
*
* Copyright IBM Corp. 2008, 2017
*
* s390-tools is free software; you can redistribute it and/or modify
* it under the terms of the MIT license. See LICENSE for details.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "lib/util_path.h"
#include "lib/util_panic.h"
#include "ipl_tools.h"
/*
* Look up for the device in /sys/devices/ hierarchy.
*
* path must be PATH_MAX large and the value will be replaced in place
*/
static int device_sysfs_path(const char *device, char *path, const size_t path_size)
{
util_assert(device != NULL, "Internal error: device is NULL");
util_assert(path != NULL, "Internal error: path is NULL");
util_assert(path_size == PATH_MAX, "Internal error: path_size is '%zu', but must be '%zu'",
path_size, PATH_MAX);
char *buf = util_path_sysfs("block/%s/device", device);
if (!realpath(buf, path)) {
free(buf);
return -1;
}
free(buf);
return 0;
}
/*
* Check if the specified device number is a valid device number
* which can be found in the /sys/bus/ccw/drivers/dasd-eckd/
* structure.
*
* This does not work when booting from tape.
*/
int ccw_is_device(const char *busid)
{
static const char *const driver_paths[] = { "dasd-eckd", "virtio_ccw", "dasd-fba" };
char *path;
size_t i;
for (i = 0; i < ARRAY_SIZE(driver_paths); i++) {
path = util_path_sysfs("bus/ccw/drivers/%s/%s", driver_paths[i], busid);
if (access(path, R_OK) == 0) {
free(path);
return 1;
}
free(path);
}
return 0;
}
/*
* Check if the specified device is a valid virtio subchannel device
*/
int ccw_is_virtio_device(const char *device)
{
char path[PATH_MAX] = { '\0' };
unsigned virtio = 0;
char *path_pattern;
if (device_sysfs_path(device, path, sizeof(path)) != 0)
return -1;
/*
* The output has the following format:
* /sys/devices/css0/0.0.0000/0.0.0000/virtio0/block/vda
*/
path_pattern = util_path_sysfs("devices/css0/%%*[0-9a-f.]/%%*[0-9a-f.]/virtio%%u");
if (sscanf(path, path_pattern, &virtio) != 1) {
free(path_pattern);
return -1;
}
free(path_pattern);
return 0;
}
/*
* Return CCW Bus ID
*/
void ccw_busid_get(const char *device, char *busid)
{
char path[PATH_MAX] = { '\0' };
char *path_pattern;
if (device_sysfs_path(device, path, sizeof(path)) != 0)
ERR_EXIT("Could not lookup device number for \"%s\"", device);
/*
* The output has the following format:
* /sys/devices/css0/0.0.0119/0.0.3f19/block/dasda
* /sys/devices/css0/0.0.0000/0.0.0000/virtio0/block/vda
*/
path_pattern = util_path_sysfs("devices/css0/%%*[0-9a-f.]/%%[0-9a-f.]");
if (sscanf(path, path_pattern, busid) != 1) {
free(path_pattern);
ERR_EXIT("Could not lookup device number for \"%s\"", device);
}
free(path_pattern);
return;
}