1// SPDX-License-Identifier: GPL-2.0
 2#include <linux/fault-inject.h>
 
 
 3#include <linux/slab.h>
 4#include <linux/mm.h>
 5#include "slab.h"
 6
 7static struct {
 8	struct fault_attr attr;
 9	bool ignore_gfp_reclaim;
10	bool cache_filter;
11} failslab = {
12	.attr = FAULT_ATTR_INITIALIZER,
13	.ignore_gfp_reclaim = true,
14	.cache_filter = false,
15};
16
17bool __should_failslab(struct kmem_cache *s, gfp_t gfpflags)
18{
 
 
19	/* No fault-injection for bootstrap cache */
20	if (unlikely(s == kmem_cache))
21		return false;
22
23	if (gfpflags & __GFP_NOFAIL)
24		return false;
25
26	if (failslab.ignore_gfp_reclaim && (gfpflags & __GFP_RECLAIM))
27		return false;
 
28
29	if (failslab.cache_filter && !(s->flags & SLAB_FAILSLAB))
30		return false;
 
 
 
 
 
 
 
 
 
31
32	return should_fail(&failslab.attr, s->object_size);
33}
 
34
35static int __init setup_failslab(char *str)
36{
37	return setup_fault_attr(&failslab.attr, str);
38}
39__setup("failslab=", setup_failslab);
40
41#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
42static int __init failslab_debugfs_init(void)
43{
44	struct dentry *dir;
45	umode_t mode = S_IFREG | S_IRUSR | S_IWUSR;
46
47	dir = fault_create_debugfs_attr("failslab", NULL, &failslab.attr);
48	if (IS_ERR(dir))
49		return PTR_ERR(dir);
50
51	if (!debugfs_create_bool("ignore-gfp-wait", mode, dir,
52				&failslab.ignore_gfp_reclaim))
53		goto fail;
54	if (!debugfs_create_bool("cache-filter", mode, dir,
55				&failslab.cache_filter))
56		goto fail;
57
58	return 0;
59fail:
60	debugfs_remove_recursive(dir);
61
62	return -ENOMEM;
63}
64
65late_initcall(failslab_debugfs_init);
66
67#endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */

 1// SPDX-License-Identifier: GPL-2.0
 2#include <linux/fault-inject.h>
 3#include <linux/error-injection.h>
 4#include <linux/debugfs.h>
 5#include <linux/slab.h>
 6#include <linux/mm.h>
 7#include "slab.h"
 8
 9static struct {
10	struct fault_attr attr;
11	bool ignore_gfp_reclaim;
12	bool cache_filter;
13} failslab = {
14	.attr = FAULT_ATTR_INITIALIZER,
15	.ignore_gfp_reclaim = true,
16	.cache_filter = false,
17};
18
19int should_failslab(struct kmem_cache *s, gfp_t gfpflags)
20{
21	int flags = 0;
22
23	/* No fault-injection for bootstrap cache */
24	if (unlikely(s == kmem_cache))
25		return 0;
26
27	if (gfpflags & __GFP_NOFAIL)
28		return 0;
29
30	if (failslab.ignore_gfp_reclaim &&
31			(gfpflags & __GFP_DIRECT_RECLAIM))
32		return 0;
33
34	if (failslab.cache_filter && !(s->flags & SLAB_FAILSLAB))
35		return 0;
36
37	/*
38	 * In some cases, it expects to specify __GFP_NOWARN
39	 * to avoid printing any information(not just a warning),
40	 * thus avoiding deadlocks. See commit 6b9dbedbe349 for
41	 * details.
42	 */
43	if (gfpflags & __GFP_NOWARN)
44		flags |= FAULT_NOWARN;
45
46	return should_fail_ex(&failslab.attr, s->object_size, flags) ? -ENOMEM : 0;
47}
48ALLOW_ERROR_INJECTION(should_failslab, ERRNO);
49
50static int __init setup_failslab(char *str)
51{
52	return setup_fault_attr(&failslab.attr, str);
53}
54__setup("failslab=", setup_failslab);
55
56#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
57static int __init failslab_debugfs_init(void)
58{
59	struct dentry *dir;
60	umode_t mode = S_IFREG | 0600;
61
62	dir = fault_create_debugfs_attr("failslab", NULL, &failslab.attr);
63	if (IS_ERR(dir))
64		return PTR_ERR(dir);
65
66	debugfs_create_bool("ignore-gfp-wait", mode, dir,
67			    &failslab.ignore_gfp_reclaim);
68	debugfs_create_bool("cache-filter", mode, dir,
69			    &failslab.cache_filter);
 
 
70
71	return 0;
 
 
 
 
72}
73
74late_initcall(failslab_debugfs_init);
75
76#endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */