diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/misc/pvpanic/pvpanic.c | |
parent | Initial commit. (diff) | |
download | linux-upstream.tar.xz linux-upstream.zip |
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/misc/pvpanic/pvpanic.c')
-rw-r--r-- | drivers/misc/pvpanic/pvpanic.c | 115 |
1 files changed, 115 insertions, 0 deletions
diff --git a/drivers/misc/pvpanic/pvpanic.c b/drivers/misc/pvpanic/pvpanic.c new file mode 100644 index 000000000..049a12006 --- /dev/null +++ b/drivers/misc/pvpanic/pvpanic.c @@ -0,0 +1,115 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Pvpanic Device Support + * + * Copyright (C) 2013 Fujitsu. + * Copyright (C) 2018 ZTE. + * Copyright (C) 2021 Oracle. + */ + +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/kexec.h> +#include <linux/mod_devicetable.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/panic_notifier.h> +#include <linux/types.h> +#include <linux/cdev.h> +#include <linux/list.h> + +#include <uapi/misc/pvpanic.h> + +#include "pvpanic.h" + +MODULE_AUTHOR("Mihai Carabas <mihai.carabas@oracle.com>"); +MODULE_DESCRIPTION("pvpanic device driver"); +MODULE_LICENSE("GPL"); + +static struct list_head pvpanic_list; +static spinlock_t pvpanic_lock; + +static void +pvpanic_send_event(unsigned int event) +{ + struct pvpanic_instance *pi_cur; + + if (!spin_trylock(&pvpanic_lock)) + return; + + list_for_each_entry(pi_cur, &pvpanic_list, list) { + if (event & pi_cur->capability & pi_cur->events) + iowrite8(event, pi_cur->base); + } + spin_unlock(&pvpanic_lock); +} + +static int +pvpanic_panic_notify(struct notifier_block *nb, unsigned long code, void *unused) +{ + unsigned int event = PVPANIC_PANICKED; + + if (kexec_crash_loaded()) + event = PVPANIC_CRASH_LOADED; + + pvpanic_send_event(event); + + return NOTIFY_DONE; +} + +/* + * Call our notifier very early on panic, deferring the + * action taken to the hypervisor. + */ +static struct notifier_block pvpanic_panic_nb = { + .notifier_call = pvpanic_panic_notify, + .priority = INT_MAX, +}; + +static void pvpanic_remove(void *param) +{ + struct pvpanic_instance *pi_cur, *pi_next; + struct pvpanic_instance *pi = param; + + spin_lock(&pvpanic_lock); + list_for_each_entry_safe(pi_cur, pi_next, &pvpanic_list, list) { + if (pi_cur == pi) { + list_del(&pi_cur->list); + break; + } + } + spin_unlock(&pvpanic_lock); +} + +int devm_pvpanic_probe(struct device *dev, struct pvpanic_instance *pi) +{ + if (!pi || !pi->base) + return -EINVAL; + + spin_lock(&pvpanic_lock); + list_add(&pi->list, &pvpanic_list); + spin_unlock(&pvpanic_lock); + + dev_set_drvdata(dev, pi); + + return devm_add_action_or_reset(dev, pvpanic_remove, pi); +} +EXPORT_SYMBOL_GPL(devm_pvpanic_probe); + +static int pvpanic_init(void) +{ + INIT_LIST_HEAD(&pvpanic_list); + spin_lock_init(&pvpanic_lock); + + atomic_notifier_chain_register(&panic_notifier_list, &pvpanic_panic_nb); + + return 0; +} +module_init(pvpanic_init); + +static void pvpanic_exit(void) +{ + atomic_notifier_chain_unregister(&panic_notifier_list, &pvpanic_panic_nb); + +} +module_exit(pvpanic_exit); |