1f2f248e36019121bad626a9a81403b5b5316b1d
[muen/linux.git] / mm / failslab.c
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
7 static 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
17 bool __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
35 static 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
42 static 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;
59 fail:
60         debugfs_remove_recursive(dir);
61
62         return -ENOMEM;
63 }
64
65 late_initcall(failslab_debugfs_init);
66
67 #endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */