// SPDX-License-Identifier: GPL-2.0

  #include <linux/fault-inject.h>

  #include <linux/slab.h>

  #include <linux/mm.h>
  #include "slab.h"

  
  static struct {
  	struct fault_attr attr;

  	bool ignore_gfp_reclaim;

  	bool cache_filter;

  } failslab = {
  	.attr = FAULT_ATTR_INITIALIZER,

  	.ignore_gfp_reclaim = true,

  	.cache_filter = false,

  };

  bool __should_failslab(struct kmem_cache *s, gfp_t gfpflags)

  {

  	/* No fault-injection for bootstrap cache */
  	if (unlikely(s == kmem_cache))
  		return false;

  	if (gfpflags & __GFP_NOFAIL)
  		return false;

  	if (failslab.ignore_gfp_reclaim &&
  			(gfpflags & __GFP_DIRECT_RECLAIM))

  		return false;

  	if (failslab.cache_filter && !(s->flags & SLAB_FAILSLAB))

  		return false;

  	return should_fail(&failslab.attr, s->object_size);

  }
  
  static int __init setup_failslab(char *str)
  {
  	return setup_fault_attr(&failslab.attr, str);
  }
  __setup("failslab=", setup_failslab);
  
  #ifdef CONFIG_FAULT_INJECTION_DEBUG_FS

  static int __init failslab_debugfs_init(void)
  {

  	struct dentry *dir;

  	umode_t mode = S_IFREG | 0600;

  	dir = fault_create_debugfs_attr("failslab", NULL, &failslab.attr);
  	if (IS_ERR(dir))
  		return PTR_ERR(dir);

  	debugfs_create_bool("ignore-gfp-wait", mode, dir,
  			    &failslab.ignore_gfp_reclaim);
  	debugfs_create_bool("cache-filter", mode, dir,
  			    &failslab.cache_filter);

  	return 0;

  }
  
  late_initcall(failslab_debugfs_init);
  
  #endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */