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