mirror of
https://github.com/ibm-s390-linux/s390-tools.git
synced 2026-08-05 02:14:52 +00:00
b627b8d8e1
This commit is based on the s390-tools-1.39.0 version. Changes on top of s390-tools-1.39.0: - Add MIT license to all source files - Add LICENSE file - Transform REAMDE to README.md (markdown) - Add AUTHORS.md file - Add CONTRIBUTING.md file - Move changelog from README to CHANGELOG.md file Reviewed-by: Stefan Haberland <sth@linux.vnet.ibm.com> Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
115 lines
2.7 KiB
C
115 lines
2.7 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 <errno.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <unistd.h>
|
|
|
|
#include "ipl_tools.h"
|
|
|
|
/*
|
|
* 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)
|
|
{
|
|
char path[PATH_MAX];
|
|
|
|
snprintf(path, sizeof(path),
|
|
"/sys/bus/ccw/drivers/dasd-eckd/%s", busid);
|
|
if (access(path, R_OK) == 0)
|
|
return 1;
|
|
snprintf(path, sizeof(path),
|
|
"/sys/bus/ccw/drivers/virtio_ccw/%s", busid);
|
|
if (access(path, R_OK) == 0)
|
|
return 1;
|
|
snprintf(path, sizeof(path), "/sys/bus/ccw/drivers/dasd-fba/%s", busid);
|
|
if (access(path, R_OK) == 0)
|
|
return 1;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Return CCW Bus ID (old sysfs)
|
|
*/
|
|
static int ccw_busid_get_sysfs_old(const char *device, char *busid)
|
|
{
|
|
char path[PATH_MAX];
|
|
char buf[4096];
|
|
int rc = 0;
|
|
FILE *fh;
|
|
|
|
snprintf(path, sizeof(path), "/sys/block/%s/uevent", device);
|
|
fh = fopen(path, "r");
|
|
if (fh == NULL)
|
|
return -1;
|
|
/*
|
|
* The uevent file contains an entry like this:
|
|
* PHYSDEVPATH=/devices/css0/0.0.206a/0.0.7e78
|
|
*/
|
|
while (fscanf(fh, "%s", buf) >= 0) {
|
|
if (strstr(buf, "PHYSDEVPATH") != NULL) {
|
|
strcpy(busid, strrchr(buf, '/') + 1);
|
|
goto out_fclose;
|
|
}
|
|
}
|
|
rc = -1;
|
|
out_fclose:
|
|
fclose(fh);
|
|
return rc;
|
|
}
|
|
|
|
/*
|
|
* Return CCW Bus ID (new sysfs)
|
|
*/
|
|
static int ccw_busid_get_sysfs_new(const char *device, char *busid)
|
|
{
|
|
char path[PATH_MAX], buf[4096];
|
|
|
|
memset(buf, 0, sizeof(buf));
|
|
snprintf(path, sizeof(path), "/sys/block/%s/device", device);
|
|
if (realpath(path, buf) == NULL)
|
|
return -1;
|
|
|
|
/*
|
|
* 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
|
|
*/
|
|
if (sscanf(buf, "/sys/devices/css0/%*[0-9a-f.]/%[0-9a-f.]", busid) != 1)
|
|
return -1;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Return the device number for a device
|
|
* dasda can be found in /sys/block/dasda/uevent or in a
|
|
* symbolic link in the same directory. the first file only
|
|
* contains the relevant information if we run on a kernel with
|
|
* has the following kernel option enabled:
|
|
* CONFIG_SYSFS_DEPRECATED
|
|
*
|
|
* This does not work when booting from tape
|
|
*/
|
|
void ccw_busid_get(const char *device, char *busid)
|
|
{
|
|
if (ccw_busid_get_sysfs_old(device, busid) == 0)
|
|
return;
|
|
if (ccw_busid_get_sysfs_new(device, busid) == 0)
|
|
return;
|
|
ERR_EXIT("Could not lookup device number for \"%s\"", device);
|
|
}
|