1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/fault-inject.h>
3 #include <linux/error-injection.h>
4 #include <linux/mm.h>
5
6 static struct {
7 struct fault_attr attr;
8
9 bool ignore_gfp_highmem;
10 bool ignore_gfp_reclaim;
11 u32 min_order;
12 } fail_page_alloc = {
13 .attr = FAULT_ATTR_INITIALIZER,
14 .ignore_gfp_reclaim = true,
15 .ignore_gfp_highmem = true,
16 .min_order = 1,
17 };
18
19 static int __init setup_fail_page_alloc(char *str)
20 {
21 return setup_fault_attr(&fail_page_alloc.attr, str);
22 }
23 __setup("fail_page_alloc=", setup_fail_page_alloc);
24
25 bool should_fail_alloc_page(gfp_t gfp_mask, unsigned int order)
26 {
27 int flags = 0;
28
29 if (order < fail_page_alloc.min_order)
30 return false;
31 if (gfp_mask & __GFP_NOFAIL)
32 return false;
33 if (fail_page_alloc.ignore_gfp_highmem && (gfp_mask & __GFP_HIGHMEM))
34 return false;
35 if (fail_page_alloc.ignore_gfp_reclaim &&
36 (gfp_mask & __GFP_DIRECT_RECLAIM))
37 return false;
38
39 /* See comment in __should_failslab() */
40 if (gfp_mask & __GFP_NOWARN)
41 flags |= FAULT_NOWARN;
42
43 return should_fail_ex(&fail_page_alloc.attr, 1 << order, flags);
44 }
45 ALLOW_ERROR_INJECTION(should_fail_alloc_page, TRUE);
46
47 #ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
48
49 static int __init fail_page_alloc_debugfs(void)
50 {
51 umode_t mode = S_IFREG | 0600;
52 struct dentry *dir;
53
54 dir = fault_create_debugfs_attr("fail_page_alloc", NULL,
55 &fail_page_alloc.attr);
56
57 debugfs_create_bool("ignore-gfp-wait", mode, dir,
58 &fail_page_alloc.ignore_gfp_reclaim);
59 debugfs_create_bool("ignore-gfp-highmem", mode, dir,
60 &fail_page_alloc.ignore_gfp_highmem);
61 debugfs_create_u32("min-order", mode, dir, &fail_page_alloc.min_order);
62
63 return 0;
64 }
65
66 late_initcall(fail_page_alloc_debugfs);
67
68 #endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */
69
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