| xj | b04a402 | 2021-11-25 15:01:52 +0800 | [diff] [blame] | 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 | 0600; | 
 | 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 */ |