mirror of
https://github.com/torvalds/linux.git
synced 2025-11-04 10:40:15 +02:00
c3d2d45b06
It is expected that most callers should _ignore_ the errors return by debugfs_create_dir() in err_inject_init(). Link: https://lkml.kernel.org/r/20230713082455.2415-1-machel@vivo.com Signed-off-by: Wang Ming <machel@vivo.com> Cc: Akinobu Mita <akinobu.mita@gmail.com> Cc: David Hildenbrand <david@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
99 lines
2.5 KiB
C
99 lines
2.5 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
#include <linux/module.h>
|
|
|
|
#include "notifier-error-inject.h"
|
|
|
|
static int debugfs_errno_set(void *data, u64 val)
|
|
{
|
|
*(int *)data = clamp_t(int, val, -MAX_ERRNO, 0);
|
|
return 0;
|
|
}
|
|
|
|
static int debugfs_errno_get(void *data, u64 *val)
|
|
{
|
|
*val = *(int *)data;
|
|
return 0;
|
|
}
|
|
|
|
DEFINE_SIMPLE_ATTRIBUTE_SIGNED(fops_errno, debugfs_errno_get, debugfs_errno_set,
|
|
"%lld\n");
|
|
|
|
static struct dentry *debugfs_create_errno(const char *name, umode_t mode,
|
|
struct dentry *parent, int *value)
|
|
{
|
|
return debugfs_create_file(name, mode, parent, value, &fops_errno);
|
|
}
|
|
|
|
static int notifier_err_inject_callback(struct notifier_block *nb,
|
|
unsigned long val, void *p)
|
|
{
|
|
int err = 0;
|
|
struct notifier_err_inject *err_inject =
|
|
container_of(nb, struct notifier_err_inject, nb);
|
|
struct notifier_err_inject_action *action;
|
|
|
|
for (action = err_inject->actions; action->name; action++) {
|
|
if (action->val == val) {
|
|
err = action->error;
|
|
break;
|
|
}
|
|
}
|
|
if (err)
|
|
pr_info("Injecting error (%d) to %s\n", err, action->name);
|
|
|
|
return notifier_from_errno(err);
|
|
}
|
|
|
|
struct dentry *notifier_err_inject_dir;
|
|
EXPORT_SYMBOL_GPL(notifier_err_inject_dir);
|
|
|
|
struct dentry *notifier_err_inject_init(const char *name, struct dentry *parent,
|
|
struct notifier_err_inject *err_inject, int priority)
|
|
{
|
|
struct notifier_err_inject_action *action;
|
|
umode_t mode = S_IFREG | S_IRUSR | S_IWUSR;
|
|
struct dentry *dir;
|
|
struct dentry *actions_dir;
|
|
|
|
err_inject->nb.notifier_call = notifier_err_inject_callback;
|
|
err_inject->nb.priority = priority;
|
|
|
|
dir = debugfs_create_dir(name, parent);
|
|
|
|
actions_dir = debugfs_create_dir("actions", dir);
|
|
|
|
for (action = err_inject->actions; action->name; action++) {
|
|
struct dentry *action_dir;
|
|
|
|
action_dir = debugfs_create_dir(action->name, actions_dir);
|
|
|
|
/*
|
|
* Create debugfs r/w file containing action->error. If
|
|
* notifier call chain is called with action->val, it will
|
|
* fail with the error code
|
|
*/
|
|
debugfs_create_errno("error", mode, action_dir, &action->error);
|
|
}
|
|
return dir;
|
|
}
|
|
EXPORT_SYMBOL_GPL(notifier_err_inject_init);
|
|
|
|
static int __init err_inject_init(void)
|
|
{
|
|
notifier_err_inject_dir =
|
|
debugfs_create_dir("notifier-error-inject", NULL);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void __exit err_inject_exit(void)
|
|
{
|
|
debugfs_remove_recursive(notifier_err_inject_dir);
|
|
}
|
|
|
|
module_init(err_inject_init);
|
|
module_exit(err_inject_exit);
|
|
|
|
MODULE_DESCRIPTION("Notifier error injection module");
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_AUTHOR("Akinobu Mita <akinobu.mita@gmail.com>");
|