Files
s390-tools/zdev/src/root.c
Vineeth Vijayan 7dd03eaeec zdev: Add build option to update initial RAM-disk by default
Some Linux distributions always include a copy of all persistent device
configuration data when updating the initial RAM-disk. This makes
chzdev's persistent device configuration changes ineffective because
device configuration directives applied in the RAM-disk take precedence
over those stored in the root filesystem.

This patch introduces a new build-time switch which allows distributions
to specify that whenever there is a persistent device configuration
change, the RAM-disk is updated automatically.

This feature can be enabled by adding 'ZDEV_ALWAYS_UPDATE_INITRD=1' as
a zdev build option. Where, by default ZDEV_ALWAYS_UPDATE_INITRD is 0.

Co-developed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
2021-01-25 13:19:33 +01:00

218 lines
5.4 KiB
C

/*
* zdev - Modify and display the persistent configuration of devices
*
* Copyright IBM Corp. 2016, 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 <stdlib.h>
#include <string.h>
#include "lib/util_path.h"
#include "device.h"
#include "devtype.h"
#include "internal.h"
#include "misc.h"
#include "path.h"
#include "root.h"
#include "select.h"
#include "setting.h"
#include "subtype.h"
static bool is_early_removed(struct device *dev)
{
struct setting *s;
s = setting_list_find(dev->persistent.settings,
internal_attr_early.name);
if (!s || !s->modified)
return false;
if (!s->actual_value || strcmp(s->actual_value, "1") != 0)
return false;
if (s->removed || strcmp(s->value, "0") == 0)
return true;
return false;
}
static void add_early_removed(struct util_list *selected)
{
int i, j;
struct devtype *dt;
struct subtype *st;
struct device *dev;
for (i = 0; devtypes[i]; i++) {
dt = devtypes[i];
for (j = 0; dt->subtypes[j]; j++) {
st = dt->subtypes[j];
util_list_iterate(&st->devices->hash.list, dev) {
if (is_early_removed(dev)) {
selected_dev_list_add(selected, dt, st,
dev->id, NULL, EXIT_OK);
}
}
}
}
}
static void add_pers_removed(struct util_list *strlist)
{
int i, j;
struct devtype *dt;
struct subtype *st;
struct device *dev;
for (i = 0; devtypes[i]; i++) {
dt = devtypes[i];
for (j = 0; dt->subtypes[j]; j++) {
st = dt->subtypes[j];
util_list_iterate(&st->devices->hash.list, dev) {
if (dev->persistent.deconfigured) {
strlist_add(strlist, "%s %s",
dev->subtype->devname, dev->id);
}
}
}
}
}
static bool is_zdev_early_0(struct selected_dev_node *sel)
{
struct setting *s;
struct device *dev;
dev = device_list_find(sel->st->devices, sel->id, NULL);
if (!dev)
return false;
s = setting_list_find(dev->persistent.settings,
internal_attr_early.name);
if (!s)
return false;
if (s->specified && strcmp(s->value, "0") == 0)
return true;
return false;
}
/* Determine if initial RAM-disk needs updating. If so, run the corresponding
* scripts if available. */
exit_code_t initrd_check(bool all_pers)
{
struct util_list *selected, *params, *mod = strlist_new();
struct selected_dev_node *sel;
struct device *dev;
char *params_str;
exit_code_t rc = EXIT_OK;
struct strlist_node *s;
struct devtype *dt;
struct select_opts *select;
debug("Checking for required initial RAM-disk update\n");
/* Get list of devices that provide the root device or require
* early configuration. */
selected = selected_dev_list_new();
if (all_pers) {
/* Add all persistently configured devices. */
select = select_opts_new();
select->configured = 1;
select_devices(select, selected, 1, 0, 0, config_persistent,
scope_mandatory, err_ignore);
select_opts_free(select);
/* Ensure that removed devices are considered. */
add_pers_removed(mod);
goto check_mod;
}
/* First add devices that had zdev:early removed or changed to 0.
* The subsequent call to select_devices() will filter out any
* duplicates. */
add_early_removed(selected);
/* Now add devices required for root file system. */
if (select_by_path(NULL, selected, config_active, scope_mandatory,
NULL, NULL, PATH_ROOT, err_ignore)) {
/* Running from an unknown root device is not an error. */
verb("Note: Could not determine if root device configuration "
"needs to be updated\n");
}
/* Finally add devices with zdev:early=1. */
select = select_opts_new();
strlist_add(&select->by_attr, "%s=1", INTERNAL_ATTR_EARLY);
select_devices(select, selected, 1, 0, 0,
config_active | config_persistent, scope_mandatory,
err_ignore);
select_opts_free(select);
check_mod:
/* Determine if any of the devices or device types has been modified. */
util_list_iterate(selected, sel) {
dt = sel->st->devtype;
/* Check devtype. */
if (devtype_needs_writing(dt, config_persistent)) {
strlist_add(mod, "Device type %s",
sel->st->devtype->name);
}
/* Check devices. */
dev = device_list_find(sel->st->devices, sel->id, NULL);
if (dev && dev->persistent.exists &&
(device_needs_writing(dev, config_persistent) || force)) {
strlist_add(mod, "%s %s", dev->subtype->devname,
dev->id);
}
}
if (util_list_is_empty(mod))
goto out;
info("Note: The initial RAM-disk must be updated for these changes to take effect:\n");
util_list_iterate(mod, s)
info(" - %s\n", s->str);
/* Check if script is available. */
if (!util_path_is_reg_file(PATH_ROOT_SCRIPT)) {
warn("A manual update of the initial RAM-disk is required.\n");
goto out;
}
if (!all_pers) {
/* Ask for confirmation. */
if (!confirm("Update initial RAM-disk now?")) {
rc = EXIT_ABORTED;
goto out;
}
}
/* Build the command line. */
params = strlist_new();
util_list_iterate(selected, sel) {
/* From the selected list, remove the devices with zdev:early=0 */
if (!is_zdev_early_0(sel)) {
strlist_add(params, "%s", sel->st->name);
strlist_add(params, "%s", sel->id);
}
}
params_str = strlist_flatten(params, " ");
strlist_free(params);
/* Run update command. */
if (misc_system(err_delayed_print, "%s %s", PATH_ROOT_SCRIPT,
params_str) != 0) {
error("Failure while updating initial RAM-disk\n");
delayed_print(DELAY_INDENT);
rc = EXIT_RUNTIME_ERROR;
}
free(params_str);
out:
strlist_free(mod);
selected_dev_list_free(selected);
return rc;
}