NFS: Add mount options to enable local caching on NFS
[linux-2.6] / mm / failslab.c
1 #include <linux/fault-inject.h>
2
3 static struct {
4         struct fault_attr attr;
5         u32 ignore_gfp_wait;
6 #ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
7         struct dentry *ignore_gfp_wait_file;
8 #endif
9 } failslab = {
10         .attr = FAULT_ATTR_INITIALIZER,
11         .ignore_gfp_wait = 1,
12 };
13
14 bool should_failslab(size_t size, gfp_t gfpflags)
15 {
16         if (gfpflags & __GFP_NOFAIL)
17                 return false;
18
19         if (failslab.ignore_gfp_wait && (gfpflags & __GFP_WAIT))
20                 return false;
21
22         return should_fail(&failslab.attr, size);
23 }
24
25 static int __init setup_failslab(char *str)
26 {
27         return setup_fault_attr(&failslab.attr, str);
28 }
29 __setup("failslab=", setup_failslab);
30
31 #ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
32
33 static int __init failslab_debugfs_init(void)
34 {
35         mode_t mode = S_IFREG | S_IRUSR | S_IWUSR;
36         struct dentry *dir;
37         int err;
38
39         err = init_fault_attr_dentries(&failslab.attr, "failslab");
40         if (err)
41                 return err;
42         dir = failslab.attr.dentries.dir;
43
44         failslab.ignore_gfp_wait_file =
45                 debugfs_create_bool("ignore-gfp-wait", mode, dir,
46                                       &failslab.ignore_gfp_wait);
47
48         if (!failslab.ignore_gfp_wait_file) {
49                 err = -ENOMEM;
50                 debugfs_remove(failslab.ignore_gfp_wait_file);
51                 cleanup_fault_attr_dentries(&failslab.attr);
52         }
53
54         return err;
55 }
56
57 late_initcall(failslab_debugfs_init);
58
59 #endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */