75 lines
		
	
	
		
			1.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			75 lines
		
	
	
		
			1.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0
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| #include <linux/fault-inject.h>
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| #include <linux/debugfs.h>
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| #include <linux/slab.h>
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| #include <linux/mm.h>
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| #include "slab.h"
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| 
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| static struct {
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| 	struct fault_attr attr;
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| 	bool ignore_gfp_reclaim;
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| 	bool cache_filter;
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| } failslab = {
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| 	.attr = FAULT_ATTR_INITIALIZER,
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| 	.ignore_gfp_reclaim = true,
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| 	.cache_filter = false,
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| };
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| 
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| bool __should_failslab(struct kmem_cache *s, gfp_t gfpflags)
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| {
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| 	int flags = 0;
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| 
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| 	/* No fault-injection for bootstrap cache */
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| 	if (unlikely(s == kmem_cache))
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| 		return false;
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| 
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| 	if (gfpflags & __GFP_NOFAIL)
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| 		return false;
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| 
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| 	if (failslab.ignore_gfp_reclaim &&
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| 			(gfpflags & __GFP_DIRECT_RECLAIM))
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| 		return false;
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| 
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| 	if (failslab.cache_filter && !(s->flags & SLAB_FAILSLAB))
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| 		return false;
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| 
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| 	/*
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| 	 * In some cases, it expects to specify __GFP_NOWARN
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| 	 * to avoid printing any information(not just a warning),
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| 	 * thus avoiding deadlocks. See commit 6b9dbedbe349 for
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| 	 * details.
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| 	 */
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| 	if (gfpflags & __GFP_NOWARN)
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| 		flags |= FAULT_NOWARN;
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| 
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| 	return should_fail_ex(&failslab.attr, s->object_size, flags);
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| }
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| 
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| static int __init setup_failslab(char *str)
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| {
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| 	return setup_fault_attr(&failslab.attr, str);
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| }
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| __setup("failslab=", setup_failslab);
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| 
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| #ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
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| static int __init failslab_debugfs_init(void)
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| {
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| 	struct dentry *dir;
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| 	umode_t mode = S_IFREG | 0600;
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| 
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| 	dir = fault_create_debugfs_attr("failslab", NULL, &failslab.attr);
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| 	if (IS_ERR(dir))
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| 		return PTR_ERR(dir);
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| 
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| 	debugfs_create_bool("ignore-gfp-wait", mode, dir,
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| 			    &failslab.ignore_gfp_reclaim);
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| 	debugfs_create_bool("cache-filter", mode, dir,
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| 			    &failslab.cache_filter);
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| 
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| 	return 0;
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| }
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| 
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| late_initcall(failslab_debugfs_init);
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| 
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| #endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */
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