/*

     Copyright (C) 2002 Richard Henderson
     Copyright (C) 2001 Rusty Russell, 2002 Rusty Russell IBM.
  
      This program is free software; you can redistribute it and/or modify
      it under the terms of the GNU General Public License as published by
      the Free Software Foundation; either version 2 of the License, or
      (at your option) any later version.
  
      This program is distributed in the hope that it will be useful,
      but WITHOUT ANY WARRANTY; without even the implied warranty of
      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      GNU General Public License for more details.
  
      You should have received a copy of the GNU General Public License
      along with this program; if not, write to the Free Software
      Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  */

  #include <linux/module.h>
  #include <linux/moduleloader.h>

  #include <linux/ftrace_event.h>

  #include <linux/init.h>

  #include <linux/kallsyms.h>

  #include <linux/fs.h>

  #include <linux/sysfs.h>

  #include <linux/kernel.h>

  #include <linux/slab.h>
  #include <linux/vmalloc.h>
  #include <linux/elf.h>

  #include <linux/proc_fs.h>

  #include <linux/seq_file.h>
  #include <linux/syscalls.h>
  #include <linux/fcntl.h>
  #include <linux/rcupdate.h>

  #include <linux/capability.h>

  #include <linux/cpu.h>
  #include <linux/moduleparam.h>
  #include <linux/errno.h>
  #include <linux/err.h>
  #include <linux/vermagic.h>
  #include <linux/notifier.h>

  #include <linux/sched.h>

  #include <linux/stop_machine.h>
  #include <linux/device.h>

  #include <linux/string.h>

  #include <linux/mutex.h>

  #include <linux/rculist.h>

  #include <asm/uaccess.h>

  #include <asm/cacheflush.h>

  #include <linux/license.h>

  #include <asm/sections.h>

  #include <linux/tracepoint.h>

  #include <linux/ftrace.h>

  #include <linux/async.h>

  #include <linux/percpu.h>

  #include <linux/kmemleak.h>

  
  #if 0
  #define DEBUGP printk
  #else
  #define DEBUGP(fmt , a...)
  #endif
  
  #ifndef ARCH_SHF_SMALL
  #define ARCH_SHF_SMALL 0
  #endif
  
  /* If this is set, the section belongs in the init part of the module */
  #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))

  /* List of modules, protected by module_mutex or preempt_disable

   * (delete uses stop_machine/add uses RCU list operations). */

  DEFINE_MUTEX(module_mutex);
  EXPORT_SYMBOL_GPL(module_mutex);

  static LIST_HEAD(modules);

  /* Block module loading/unloading? */
  int modules_disabled = 0;

  /* Waiting for a module to finish initializing? */
  static DECLARE_WAIT_QUEUE_HEAD(module_wq);

  static BLOCKING_NOTIFIER_HEAD(module_notify_list);

  /* Bounds of module allocation, for speeding __module_address */

  static unsigned long module_addr_min = -1UL, module_addr_max = 0;

  int register_module_notifier(struct notifier_block * nb)
  {

  	return blocking_notifier_chain_register(&module_notify_list, nb);

  }
  EXPORT_SYMBOL(register_module_notifier);
  
  int unregister_module_notifier(struct notifier_block * nb)
  {

  	return blocking_notifier_chain_unregister(&module_notify_list, nb);

  }
  EXPORT_SYMBOL(unregister_module_notifier);

  /* We require a truly strong try_module_get(): 0 means failure due to
     ongoing or failed initialization etc. */

  static inline int strong_try_module_get(struct module *mod)
  {
  	if (mod && mod->state == MODULE_STATE_COMING)

  		return -EBUSY;
  	if (try_module_get(mod))

  		return 0;

  	else
  		return -ENOENT;

  }

  static inline void add_taint_module(struct module *mod, unsigned flag)
  {
  	add_taint(flag);

  	mod->taints |= (1U << flag);

  }

  /*
   * A thread that wants to hold a reference to a module only while it
   * is running can call this to safely exit.  nfsd and lockd use this.

   */
  void __module_put_and_exit(struct module *mod, long code)
  {
  	module_put(mod);
  	do_exit(code);
  }
  EXPORT_SYMBOL(__module_put_and_exit);

  /* Find a module section: 0 means not found. */
  static unsigned int find_sec(Elf_Ehdr *hdr,
  			     Elf_Shdr *sechdrs,
  			     const char *secstrings,
  			     const char *name)
  {
  	unsigned int i;
  
  	for (i = 1; i < hdr->e_shnum; i++)
  		/* Alloc bit cleared means "ignore it." */
  		if ((sechdrs[i].sh_flags & SHF_ALLOC)
  		    && strcmp(secstrings+sechdrs[i].sh_name, name) == 0)
  			return i;
  	return 0;
  }

  /* Find a module section, or NULL. */
  static void *section_addr(Elf_Ehdr *hdr, Elf_Shdr *shdrs,
  			  const char *secstrings, const char *name)
  {
  	/* Section 0 has sh_addr 0. */
  	return (void *)shdrs[find_sec(hdr, shdrs, secstrings, name)].sh_addr;
  }
  
  /* Find a module section, or NULL.  Fill in number of "objects" in section. */
  static void *section_objs(Elf_Ehdr *hdr,
  			  Elf_Shdr *sechdrs,
  			  const char *secstrings,
  			  const char *name,
  			  size_t object_size,
  			  unsigned int *num)
  {
  	unsigned int sec = find_sec(hdr, sechdrs, secstrings, name);
  
  	/* Section 0 has sh_addr 0 and sh_size 0. */
  	*num = sechdrs[sec].sh_size / object_size;
  	return (void *)sechdrs[sec].sh_addr;
  }

  /* Provided by the linker */
  extern const struct kernel_symbol __start___ksymtab[];
  extern const struct kernel_symbol __stop___ksymtab[];
  extern const struct kernel_symbol __start___ksymtab_gpl[];
  extern const struct kernel_symbol __stop___ksymtab_gpl[];

  extern const struct kernel_symbol __start___ksymtab_gpl_future[];
  extern const struct kernel_symbol __stop___ksymtab_gpl_future[];

  extern const struct kernel_symbol __start___ksymtab_gpl_future[];
  extern const struct kernel_symbol __stop___ksymtab_gpl_future[];

  extern const unsigned long __start___kcrctab[];
  extern const unsigned long __start___kcrctab_gpl[];

  extern const unsigned long __start___kcrctab_gpl_future[];

  #ifdef CONFIG_UNUSED_SYMBOLS
  extern const struct kernel_symbol __start___ksymtab_unused[];
  extern const struct kernel_symbol __stop___ksymtab_unused[];
  extern const struct kernel_symbol __start___ksymtab_unused_gpl[];
  extern const struct kernel_symbol __stop___ksymtab_unused_gpl[];

  extern const unsigned long __start___kcrctab_unused[];
  extern const unsigned long __start___kcrctab_unused_gpl[];

  #endif

  
  #ifndef CONFIG_MODVERSIONS
  #define symversion(base, idx) NULL
  #else

  #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)

  #endif

  static bool each_symbol_in_section(const struct symsearch *arr,
  				   unsigned int arrsize,
  				   struct module *owner,
  				   bool (*fn)(const struct symsearch *syms,
  					      struct module *owner,
  					      unsigned int symnum, void *data),
  				   void *data)

  {

  	unsigned int i, j;

  	for (j = 0; j < arrsize; j++) {
  		for (i = 0; i < arr[j].stop - arr[j].start; i++)
  			if (fn(&arr[j], owner, i, data))
  				return true;

  	}

  
  	return false;

  }

  /* Returns true as soon as fn returns true, otherwise false. */

  bool each_symbol(bool (*fn)(const struct symsearch *arr, struct module *owner,
  			    unsigned int symnum, void *data), void *data)

  {
  	struct module *mod;

  	const struct symsearch arr[] = {
  		{ __start___ksymtab, __stop___ksymtab, __start___kcrctab,

  		  NOT_GPL_ONLY, false },

  		{ __start___ksymtab_gpl, __stop___ksymtab_gpl,

  		  __start___kcrctab_gpl,
  		  GPL_ONLY, false },

  		{ __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,

  		  __start___kcrctab_gpl_future,
  		  WILL_BE_GPL_ONLY, false },

  #ifdef CONFIG_UNUSED_SYMBOLS

  		{ __start___ksymtab_unused, __stop___ksymtab_unused,

  		  __start___kcrctab_unused,
  		  NOT_GPL_ONLY, true },

  		{ __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,

  		  __start___kcrctab_unused_gpl,
  		  GPL_ONLY, true },

  #endif

  	};

  	if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data))
  		return true;

  	list_for_each_entry_rcu(mod, &modules, list) {

  		struct symsearch arr[] = {
  			{ mod->syms, mod->syms + mod->num_syms, mod->crcs,

  			  NOT_GPL_ONLY, false },

  			{ mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,

  			  mod->gpl_crcs,
  			  GPL_ONLY, false },

  			{ mod->gpl_future_syms,
  			  mod->gpl_future_syms + mod->num_gpl_future_syms,

  			  mod->gpl_future_crcs,
  			  WILL_BE_GPL_ONLY, false },

  #ifdef CONFIG_UNUSED_SYMBOLS

  			{ mod->unused_syms,
  			  mod->unused_syms + mod->num_unused_syms,

  			  mod->unused_crcs,
  			  NOT_GPL_ONLY, true },

  			{ mod->unused_gpl_syms,
  			  mod->unused_gpl_syms + mod->num_unused_gpl_syms,

  			  mod->unused_gpl_crcs,
  			  GPL_ONLY, true },

  #endif

  		};

  		if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data))
  			return true;
  	}
  	return false;
  }

  EXPORT_SYMBOL_GPL(each_symbol);

  
  struct find_symbol_arg {
  	/* Input */
  	const char *name;
  	bool gplok;
  	bool warn;
  
  	/* Output */
  	struct module *owner;
  	const unsigned long *crc;

  	const struct kernel_symbol *sym;

  };
  
  static bool find_symbol_in_section(const struct symsearch *syms,
  				   struct module *owner,
  				   unsigned int symnum, void *data)
  {
  	struct find_symbol_arg *fsa = data;
  
  	if (strcmp(syms->start[symnum].name, fsa->name) != 0)
  		return false;
  
  	if (!fsa->gplok) {
  		if (syms->licence == GPL_ONLY)
  			return false;
  		if (syms->licence == WILL_BE_GPL_ONLY && fsa->warn) {
  			printk(KERN_WARNING "Symbol %s is being used "
  			       "by a non-GPL module, which will not "
  			       "be allowed in the future
  ", fsa->name);
  			printk(KERN_WARNING "Please see the file "
  			       "Documentation/feature-removal-schedule.txt "
  			       "in the kernel source tree for more details.
  ");

  		}

  	}

  #ifdef CONFIG_UNUSED_SYMBOLS

  	if (syms->unused && fsa->warn) {
  		printk(KERN_WARNING "Symbol %s is marked as UNUSED, "
  		       "however this module is using it.
  ", fsa->name);
  		printk(KERN_WARNING
  		       "This symbol will go away in the future.
  ");
  		printk(KERN_WARNING
  		       "Please evalute if this is the right api to use and if "
  		       "it really is, submit a report the linux kernel "
  		       "mailinglist together with submitting your code for "
  		       "inclusion.
  ");
  	}

  #endif

  
  	fsa->owner = owner;
  	fsa->crc = symversion(syms->crcs, symnum);

  	fsa->sym = &syms->start[symnum];

  	return true;
  }

  /* Find a symbol and return it, along with, (optional) crc and
   * (optional) module which owns it */

  const struct kernel_symbol *find_symbol(const char *name,
  					struct module **owner,
  					const unsigned long **crc,
  					bool gplok,
  					bool warn)

  {
  	struct find_symbol_arg fsa;
  
  	fsa.name = name;
  	fsa.gplok = gplok;
  	fsa.warn = warn;
  
  	if (each_symbol(find_symbol_in_section, &fsa)) {
  		if (owner)
  			*owner = fsa.owner;
  		if (crc)
  			*crc = fsa.crc;

  		return fsa.sym;

  	}

  	DEBUGP("Failed to find symbol %s
  ", name);

  	return NULL;

  }

  EXPORT_SYMBOL_GPL(find_symbol);

  /* Search for module by name: must hold module_mutex. */

  struct module *find_module(const char *name)

  {
  	struct module *mod;
  
  	list_for_each_entry(mod, &modules, list) {
  		if (strcmp(mod->name, name) == 0)
  			return mod;
  	}
  	return NULL;
  }

  EXPORT_SYMBOL_GPL(find_module);

  
  #ifdef CONFIG_SMP

  
  #ifdef CONFIG_HAVE_DYNAMIC_PER_CPU_AREA
  
  static void *percpu_modalloc(unsigned long size, unsigned long align,
  			     const char *name)
  {
  	void *ptr;
  
  	if (align > PAGE_SIZE) {
  		printk(KERN_WARNING "%s: per-cpu alignment %li > %li
  ",
  		       name, align, PAGE_SIZE);
  		align = PAGE_SIZE;
  	}

  	ptr = __alloc_reserved_percpu(size, align);

  	if (!ptr)
  		printk(KERN_WARNING
  		       "Could not allocate %lu bytes percpu data
  ", size);
  	return ptr;
  }
  
  static void percpu_modfree(void *freeme)
  {
  	free_percpu(freeme);
  }
  
  #else /* ... !CONFIG_HAVE_DYNAMIC_PER_CPU_AREA */

  /* Number of blocks used and allocated. */
  static unsigned int pcpu_num_used, pcpu_num_allocated;
  /* Size of each block.  -ve means used. */
  static int *pcpu_size;
  
  static int split_block(unsigned int i, unsigned short size)
  {
  	/* Reallocation required? */
  	if (pcpu_num_used + 1 > pcpu_num_allocated) {

  		int *new;
  
  		new = krealloc(pcpu_size, sizeof(new[0])*pcpu_num_allocated*2,
  			       GFP_KERNEL);

  		if (!new)
  			return 0;

  		pcpu_num_allocated *= 2;

  		pcpu_size = new;
  	}
  
  	/* Insert a new subblock */
  	memmove(&pcpu_size[i+1], &pcpu_size[i],
  		sizeof(pcpu_size[0]) * (pcpu_num_used - i));
  	pcpu_num_used++;
  
  	pcpu_size[i+1] -= size;
  	pcpu_size[i] = size;
  	return 1;
  }
  
  static inline unsigned int block_size(int val)
  {
  	if (val < 0)
  		return -val;
  	return val;
  }

  static void *percpu_modalloc(unsigned long size, unsigned long align,
  			     const char *name)

  {
  	unsigned long extra;
  	unsigned int i;
  	void *ptr;

  	int cpu;

  	if (align > PAGE_SIZE) {
  		printk(KERN_WARNING "%s: per-cpu alignment %li > %li
  ",
  		       name, align, PAGE_SIZE);
  		align = PAGE_SIZE;

  	}

  
  	ptr = __per_cpu_start;
  	for (i = 0; i < pcpu_num_used; ptr += block_size(pcpu_size[i]), i++) {
  		/* Extra for alignment requirement. */
  		extra = ALIGN((unsigned long)ptr, align) - (unsigned long)ptr;
  		BUG_ON(i == 0 && extra != 0);
  
  		if (pcpu_size[i] < 0 || pcpu_size[i] < extra + size)
  			continue;
  
  		/* Transfer extra to previous block. */
  		if (pcpu_size[i-1] < 0)
  			pcpu_size[i-1] -= extra;
  		else
  			pcpu_size[i-1] += extra;
  		pcpu_size[i] -= extra;
  		ptr += extra;
  
  		/* Split block if warranted */
  		if (pcpu_size[i] - size > sizeof(unsigned long))
  			if (!split_block(i, size))
  				return NULL;

  		/* add the per-cpu scanning areas */
  		for_each_possible_cpu(cpu)
  			kmemleak_alloc(ptr + per_cpu_offset(cpu), size, 0,
  				       GFP_KERNEL);

  		/* Mark allocated */
  		pcpu_size[i] = -pcpu_size[i];
  		return ptr;
  	}
  
  	printk(KERN_WARNING "Could not allocate %lu bytes percpu data
  ",
  	       size);
  	return NULL;
  }
  
  static void percpu_modfree(void *freeme)
  {
  	unsigned int i;
  	void *ptr = __per_cpu_start + block_size(pcpu_size[0]);

  	int cpu;

  
  	/* First entry is core kernel percpu data. */
  	for (i = 1; i < pcpu_num_used; ptr += block_size(pcpu_size[i]), i++) {
  		if (ptr == freeme) {
  			pcpu_size[i] = -pcpu_size[i];
  			goto free;
  		}
  	}
  	BUG();
  
   free:

  	/* remove the per-cpu scanning areas */
  	for_each_possible_cpu(cpu)
  		kmemleak_free(freeme + per_cpu_offset(cpu));

  	/* Merge with previous? */
  	if (pcpu_size[i-1] >= 0) {
  		pcpu_size[i-1] += pcpu_size[i];
  		pcpu_num_used--;
  		memmove(&pcpu_size[i], &pcpu_size[i+1],
  			(pcpu_num_used - i) * sizeof(pcpu_size[0]));
  		i--;
  	}
  	/* Merge with next? */
  	if (i+1 < pcpu_num_used && pcpu_size[i+1] >= 0) {
  		pcpu_size[i] += pcpu_size[i+1];
  		pcpu_num_used--;
  		memmove(&pcpu_size[i+1], &pcpu_size[i+2],
  			(pcpu_num_used - (i+1)) * sizeof(pcpu_size[0]));
  	}
  }

  static int percpu_modinit(void)
  {
  	pcpu_num_used = 2;
  	pcpu_num_allocated = 2;
  	pcpu_size = kmalloc(sizeof(pcpu_size[0]) * pcpu_num_allocated,
  			    GFP_KERNEL);
  	/* Static in-kernel percpu data (used). */

  	pcpu_size[0] = -(__per_cpu_end-__per_cpu_start);

  	/* Free room. */
  	pcpu_size[1] = PERCPU_ENOUGH_ROOM + pcpu_size[0];
  	if (pcpu_size[1] < 0) {
  		printk(KERN_ERR "No per-cpu room for modules.
  ");
  		pcpu_num_used = 1;
  	}
  
  	return 0;

  }

  __initcall(percpu_modinit);

  #endif /* CONFIG_HAVE_DYNAMIC_PER_CPU_AREA */

  static unsigned int find_pcpusec(Elf_Ehdr *hdr,
  				 Elf_Shdr *sechdrs,
  				 const char *secstrings)
  {
  	return find_sec(hdr, sechdrs, secstrings, ".data.percpu");
  }
  
  static void percpu_modcopy(void *pcpudest, const void *from, unsigned long size)
  {
  	int cpu;
  
  	for_each_possible_cpu(cpu)
  		memcpy(pcpudest + per_cpu_offset(cpu), from, size);
  }

  #else /* ... !CONFIG_SMP */

  static inline void *percpu_modalloc(unsigned long size, unsigned long align,
  				    const char *name)

  {
  	return NULL;
  }
  static inline void percpu_modfree(void *pcpuptr)
  {
  	BUG();
  }
  static inline unsigned int find_pcpusec(Elf_Ehdr *hdr,
  					Elf_Shdr *sechdrs,
  					const char *secstrings)
  {
  	return 0;
  }
  static inline void percpu_modcopy(void *pcpudst, const void *src,
  				  unsigned long size)
  {
  	/* pcpusec should be 0, and size of that section should be 0. */
  	BUG_ON(size != 0);
  }

  #endif /* CONFIG_SMP */

  #define MODINFO_ATTR(field)	\
  static void setup_modinfo_##field(struct module *mod, const char *s)  \
  {                                                                     \
  	mod->field = kstrdup(s, GFP_KERNEL);                          \
  }                                                                     \
  static ssize_t show_modinfo_##field(struct module_attribute *mattr,   \
  	                struct module *mod, char *buffer)             \
  {                                                                     \
  	return sprintf(buffer, "%s
  ", mod->field);                   \
  }                                                                     \
  static int modinfo_##field##_exists(struct module *mod)               \
  {                                                                     \
  	return mod->field != NULL;                                    \
  }                                                                     \
  static void free_modinfo_##field(struct module *mod)                  \
  {                                                                     \

  	kfree(mod->field);                                            \
  	mod->field = NULL;                                            \

  }                                                                     \
  static struct module_attribute modinfo_##field = {                    \

  	.attr = { .name = __stringify(field), .mode = 0444 },         \

  	.show = show_modinfo_##field,                                 \
  	.setup = setup_modinfo_##field,                               \
  	.test = modinfo_##field##_exists,                             \
  	.free = free_modinfo_##field,                                 \
  };
  
  MODINFO_ATTR(version);
  MODINFO_ATTR(srcversion);

  static char last_unloaded_module[MODULE_NAME_LEN+1];

  #ifdef CONFIG_MODULE_UNLOAD

  /* Init the unload section of the module. */
  static void module_unload_init(struct module *mod)
  {

  	int cpu;

  
  	INIT_LIST_HEAD(&mod->modules_which_use_me);

  	for_each_possible_cpu(cpu)
  		local_set(__module_ref_addr(mod, cpu), 0);

  	/* Hold reference count during initialization. */

  	local_set(__module_ref_addr(mod, raw_smp_processor_id()), 1);

  	/* Backwards compatibility macros put refcount during init. */
  	mod->waiter = current;
  }
  
  /* modules using other modules */
  struct module_use
  {
  	struct list_head list;
  	struct module *module_which_uses;
  };
  
  /* Does a already use b? */
  static int already_uses(struct module *a, struct module *b)
  {
  	struct module_use *use;
  
  	list_for_each_entry(use, &b->modules_which_use_me, list) {
  		if (use->module_which_uses == a) {
  			DEBUGP("%s uses %s!
  ", a->name, b->name);
  			return 1;
  		}
  	}
  	DEBUGP("%s does not use %s!
  ", a->name, b->name);
  	return 0;
  }
  
  /* Module a uses b */

  int use_module(struct module *a, struct module *b)

  {
  	struct module_use *use;

  	int no_warn, err;

  	if (b == NULL || already_uses(a, b)) return 1;

  	/* If we're interrupted or time out, we fail. */
  	if (wait_event_interruptible_timeout(
  		    module_wq, (err = strong_try_module_get(b)) != -EBUSY,
  		    30 * HZ) <= 0) {
  		printk("%s: gave up waiting for init of module %s.
  ",
  		       a->name, b->name);
  		return 0;
  	}
  
  	/* If strong_try_module_get() returned a different error, we fail. */
  	if (err)

  		return 0;
  
  	DEBUGP("Allocating new usage for %s.
  ", a->name);
  	use = kmalloc(sizeof(*use), GFP_ATOMIC);
  	if (!use) {
  		printk("%s: out of memory loading
  ", a->name);
  		module_put(b);
  		return 0;
  	}
  
  	use->module_which_uses = a;
  	list_add(&use->list, &b->modules_which_use_me);

  	no_warn = sysfs_create_link(b->holders_dir, &a->mkobj.kobj, a->name);

  	return 1;
  }

  EXPORT_SYMBOL_GPL(use_module);

  
  /* Clear the unload stuff of the module. */
  static void module_unload_free(struct module *mod)
  {
  	struct module *i;
  
  	list_for_each_entry(i, &modules, list) {
  		struct module_use *use;
  
  		list_for_each_entry(use, &i->modules_which_use_me, list) {
  			if (use->module_which_uses == mod) {
  				DEBUGP("%s unusing %s
  ", mod->name, i->name);
  				module_put(i);
  				list_del(&use->list);
  				kfree(use);

  				sysfs_remove_link(i->holders_dir, mod->name);

  				/* There can be at most one match. */
  				break;
  			}
  		}
  	}
  }
  
  #ifdef CONFIG_MODULE_FORCE_UNLOAD

  static inline int try_force_unload(unsigned int flags)

  {
  	int ret = (flags & O_TRUNC);
  	if (ret)

  		add_taint(TAINT_FORCED_RMMOD);

  	return ret;
  }
  #else

  static inline int try_force_unload(unsigned int flags)

  {
  	return 0;
  }
  #endif /* CONFIG_MODULE_FORCE_UNLOAD */
  
  struct stopref
  {
  	struct module *mod;
  	int flags;
  	int *forced;
  };
  
  /* Whole machine is stopped with interrupts off when this runs. */
  static int __try_stop_module(void *_sref)
  {
  	struct stopref *sref = _sref;

  	/* If it's not unused, quit unless we're forcing. */
  	if (module_refcount(sref->mod) != 0) {

  		if (!(*sref->forced = try_force_unload(sref->flags)))

  			return -EWOULDBLOCK;
  	}
  
  	/* Mark it as dying. */
  	sref->mod->state = MODULE_STATE_GOING;
  	return 0;
  }
  
  static int try_stop_module(struct module *mod, int flags, int *forced)
  {

  	if (flags & O_NONBLOCK) {
  		struct stopref sref = { mod, flags, forced };

  		return stop_machine(__try_stop_module, &sref, NULL);

  	} else {
  		/* We don't need to stop the machine for this. */
  		mod->state = MODULE_STATE_GOING;
  		synchronize_sched();
  		return 0;
  	}

  }
  
  unsigned int module_refcount(struct module *mod)
  {

  	unsigned int total = 0;
  	int cpu;

  	for_each_possible_cpu(cpu)
  		total += local_read(__module_ref_addr(mod, cpu));

  	return total;
  }
  EXPORT_SYMBOL(module_refcount);
  
  /* This exists whether we can unload or not */
  static void free_module(struct module *mod);
  
  static void wait_for_zero_refcount(struct module *mod)
  {

  	/* Since we might sleep for some time, release the mutex first */

  	mutex_unlock(&module_mutex);

  	for (;;) {
  		DEBUGP("Looking at refcount...
  ");
  		set_current_state(TASK_UNINTERRUPTIBLE);
  		if (module_refcount(mod) == 0)
  			break;
  		schedule();
  	}
  	current->state = TASK_RUNNING;

  	mutex_lock(&module_mutex);

  }

  SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
  		unsigned int, flags)

  {
  	struct module *mod;

  	char name[MODULE_NAME_LEN];

  	int ret, forced = 0;

  	if (!capable(CAP_SYS_MODULE) || modules_disabled)

  		return -EPERM;
  
  	if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
  		return -EFAULT;
  	name[MODULE_NAME_LEN-1] = '\0';

  	/* Create stop_machine threads since free_module relies on
  	 * a non-failing stop_machine call. */
  	ret = stop_machine_create();
  	if (ret)
  		return ret;
  
  	if (mutex_lock_interruptible(&module_mutex) != 0) {
  		ret = -EINTR;
  		goto out_stop;
  	}

  
  	mod = find_module(name);
  	if (!mod) {
  		ret = -ENOENT;
  		goto out;
  	}
  
  	if (!list_empty(&mod->modules_which_use_me)) {
  		/* Other modules depend on us: get rid of them first. */
  		ret = -EWOULDBLOCK;
  		goto out;
  	}
  
  	/* Doing init or already dying? */
  	if (mod->state != MODULE_STATE_LIVE) {
  		/* FIXME: if (force), slam module count and wake up
                     waiter --RR */
  		DEBUGP("%s already dying
  ", mod->name);
  		ret = -EBUSY;
  		goto out;
  	}
  
  	/* If it has an init func, it must have an exit func to unload */

  	if (mod->init && !mod->exit) {

  		forced = try_force_unload(flags);

  		if (!forced) {
  			/* This module can't be removed */
  			ret = -EBUSY;
  			goto out;
  		}
  	}
  
  	/* Set this up before setting mod->state */
  	mod->waiter = current;
  
  	/* Stop the machine so refcounts can't move and disable module. */
  	ret = try_stop_module(mod, flags, &forced);
  	if (ret != 0)
  		goto out;
  
  	/* Never wait if forced. */
  	if (!forced && module_refcount(mod) != 0)
  		wait_for_zero_refcount(mod);

  	mutex_unlock(&module_mutex);

  	/* Final destruction now noone is using it. */

  	if (mod->exit != NULL)

  		mod->exit();

  	blocking_notifier_call_chain(&module_notify_list,
  				     MODULE_STATE_GOING, mod);

  	async_synchronize_full();

  	mutex_lock(&module_mutex);

  	/* Store the name of the last unloaded module for diagnostic purposes */

  	strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));

  	ddebug_remove_module(mod->name);

  	free_module(mod);
  
   out:

  	mutex_unlock(&module_mutex);

  out_stop:
  	stop_machine_destroy();

  	return ret;
  }

  static inline void print_unload_info(struct seq_file *m, struct module *mod)

  {
  	struct module_use *use;
  	int printed_something = 0;
  
  	seq_printf(m, " %u ", module_refcount(mod));
  
  	/* Always include a trailing , so userspace can differentiate
             between this and the old multi-field proc format. */
  	list_for_each_entry(use, &mod->modules_which_use_me, list) {
  		printed_something = 1;
  		seq_printf(m, "%s,", use->module_which_uses->name);
  	}

  	if (mod->init != NULL && mod->exit == NULL) {
  		printed_something = 1;
  		seq_printf(m, "[permanent],");
  	}
  
  	if (!printed_something)
  		seq_printf(m, "-");
  }
  
  void __symbol_put(const char *symbol)
  {
  	struct module *owner;

  	preempt_disable();

  	if (!find_symbol(symbol, &owner, NULL, true, false))

  		BUG();
  	module_put(owner);

  	preempt_enable();

  }
  EXPORT_SYMBOL(__symbol_put);
  
  void symbol_put_addr(void *addr)
  {

  	struct module *modaddr;

  	if (core_kernel_text((unsigned long)addr))
  		return;

  	/* module_text_address is safe here: we're supposed to have reference
  	 * to module from symbol_get, so it can't go away. */
  	modaddr = __module_text_address((unsigned long)addr);
  	BUG_ON(!modaddr);

  	module_put(modaddr);

  }
  EXPORT_SYMBOL_GPL(symbol_put_addr);
  
  static ssize_t show_refcnt(struct module_attribute *mattr,
  			   struct module *mod, char *buffer)
  {

  	return sprintf(buffer, "%u
  ", module_refcount(mod));

  }
  
  static struct module_attribute refcnt = {

  	.attr = { .name = "refcnt", .mode = 0444 },

  	.show = show_refcnt,
  };

  void module_put(struct module *module)
  {
  	if (module) {
  		unsigned int cpu = get_cpu();

  		local_dec(__module_ref_addr(module, cpu));

  		/* Maybe they're waiting for us to drop reference? */
  		if (unlikely(!module_is_live(module)))
  			wake_up_process(module->waiter);
  		put_cpu();
  	}
  }
  EXPORT_SYMBOL(module_put);

  #else /* !CONFIG_MODULE_UNLOAD */

  static inline void print_unload_info(struct seq_file *m, struct module *mod)

  {
  	/* We don't know the usage count, or what modules are using. */
  	seq_printf(m, " - -");
  }
  
  static inline void module_unload_free(struct module *mod)
  {
  }

  int use_module(struct module *a, struct module *b)

  {

  	return strong_try_module_get(b) == 0;

  }

  EXPORT_SYMBOL_GPL(use_module);

  
  static inline void module_unload_init(struct module *mod)
  {
  }
  #endif /* CONFIG_MODULE_UNLOAD */

  static ssize_t show_initstate(struct module_attribute *mattr,
  			   struct module *mod, char *buffer)
  {
  	const char *state = "unknown";
  
  	switch (mod->state) {
  	case MODULE_STATE_LIVE:
  		state = "live";
  		break;
  	case MODULE_STATE_COMING:
  		state = "coming";
  		break;
  	case MODULE_STATE_GOING:
  		state = "going";
  		break;
  	}
  	return sprintf(buffer, "%s
  ", state);
  }
  
  static struct module_attribute initstate = {

  	.attr = { .name = "initstate", .mode = 0444 },

  	.show = show_initstate,
  };

  static struct module_attribute *modinfo_attrs[] = {
  	&modinfo_version,
  	&modinfo_srcversion,

  	&initstate,

  #ifdef CONFIG_MODULE_UNLOAD
  	&refcnt,
  #endif
  	NULL,
  };

  static const char vermagic[] = VERMAGIC_STRING;

  static int try_to_force_load(struct module *mod, const char *reason)

  {
  #ifdef CONFIG_MODULE_FORCE_LOAD

  	if (!test_taint(TAINT_FORCED_MODULE))

  		printk(KERN_WARNING "%s: %s: kernel tainted.
  ",
  		       mod->name, reason);

  	add_taint_module(mod, TAINT_FORCED_MODULE);
  	return 0;
  #else
  	return -ENOEXEC;
  #endif
  }

  #ifdef CONFIG_MODVERSIONS
  static int check_version(Elf_Shdr *sechdrs,
  			 unsigned int versindex,
  			 const char *symname,
  			 struct module *mod, 
  			 const unsigned long *crc)
  {
  	unsigned int i, num_versions;
  	struct modversion_info *versions;
  
  	/* Exporting module didn't supply crcs?  OK, we're already tainted. */
  	if (!crc)
  		return 1;

  	/* No versions at all?  modprobe --force does this. */
  	if (versindex == 0)
  		return try_to_force_load(mod, symname) == 0;

  	versions = (void *) sechdrs[versindex].sh_addr;
  	num_versions = sechdrs[versindex].sh_size
  		/ sizeof(struct modversion_info);
  
  	for (i = 0; i < num_versions; i++) {
  		if (strcmp(versions[i].name, symname) != 0)
  			continue;
  
  		if (versions[i].crc == *crc)
  			return 1;

  		DEBUGP("Found checksum %lX vs module %lX
  ",
  		       *crc, versions[i].crc);

  		goto bad_version;

  	}

  	printk(KERN_WARNING "%s: no symbol version for %s
  ",
  	       mod->name, symname);
  	return 0;

  
  bad_version:
  	printk("%s: disagrees about version of symbol %s
  ",
  	       mod->name, symname);
  	return 0;

  }
  
  static inline int check_modstruct_version(Elf_Shdr *sechdrs,
  					  unsigned int versindex,
  					  struct module *mod)
  {
  	const unsigned long *crc;

  	if (!find_symbol(MODULE_SYMBOL_PREFIX "module_layout", NULL,
  			 &crc, true, false))

  		BUG();

  	return check_version(sechdrs, versindex, "module_layout", mod, crc);

  }

  /* First part is kernel version, which we ignore if module has crcs. */
  static inline int same_magic(const char *amagic, const char *bmagic,
  			     bool has_crcs)

  {

  	if (has_crcs) {
  		amagic += strcspn(amagic, " ");
  		bmagic += strcspn(bmagic, " ");
  	}

  	return strcmp(amagic, bmagic) == 0;
  }
  #else
  static inline int check_version(Elf_Shdr *sechdrs,
  				unsigned int versindex,
  				const char *symname,
  				struct module *mod, 
  				const unsigned long *crc)
  {
  	return 1;
  }
  
  static inline int check_modstruct_version(Elf_Shdr *sechdrs,
  					  unsigned int versindex,
  					  struct module *mod)
  {
  	return 1;
  }

  static inline int same_magic(const char *amagic, const char *bmagic,
  			     bool has_crcs)

  {
  	return strcmp(amagic, bmagic) == 0;
  }
  #endif /* CONFIG_MODVERSIONS */
  
  /* Resolve a symbol for this module.  I.e. if we find one, record usage.
     Must be holding module_mutex. */

  static const struct kernel_symbol *resolve_symbol(Elf_Shdr *sechdrs,
  						  unsigned int versindex,
  						  const char *name,
  						  struct module *mod)

  {
  	struct module *owner;

  	const struct kernel_symbol *sym;

  	const unsigned long *crc;

  	sym = find_symbol(name, &owner, &crc,

  			  !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true);

  	/* use_module can fail due to OOM,
  	   or module initialization or unloading */
  	if (sym) {

  		if (!check_version(sechdrs, versindex, name, mod, crc) ||
  		    !use_module(mod, owner))

  			sym = NULL;

  	}

  	return sym;

  }

  /*
   * /sys/module/foo/sections stuff
   * J. Corbet <corbet@lwn.net>
   */

  #if defined(CONFIG_KALLSYMS) && defined(CONFIG_SYSFS)

  struct module_sect_attr
  {
  	struct module_attribute mattr;
  	char *name;
  	unsigned long address;
  };
  
  struct module_sect_attrs
  {
  	struct attribute_group grp;
  	unsigned int nsections;
  	struct module_sect_attr attrs[0];
  };

  static ssize_t module_sect_show(struct module_attribute *mattr,
  				struct module *mod, char *buf)
  {
  	struct module_sect_attr *sattr =
  		container_of(mattr, struct module_sect_attr, mattr);
  	return sprintf(buf, "0x%lx
  ", sattr->address);
  }

  static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
  {

  	unsigned int section;

  
  	for (section = 0; section < sect_attrs->nsections; section++)
  		kfree(sect_attrs->attrs[section].name);
  	kfree(sect_attrs);
  }

  static void add_sect_attrs(struct module *mod, unsigned int nsect,
  		char *secstrings, Elf_Shdr *sechdrs)
  {
  	unsigned int nloaded = 0, i, size[2];
  	struct module_sect_attrs *sect_attrs;
  	struct module_sect_attr *sattr;
  	struct attribute **gattr;

  	/* Count loaded sections and allocate structures */
  	for (i = 0; i < nsect; i++)
  		if (sechdrs[i].sh_flags & SHF_ALLOC)
  			nloaded++;
  	size[0] = ALIGN(sizeof(*sect_attrs)
  			+ nloaded * sizeof(sect_attrs->attrs[0]),
  			sizeof(sect_attrs->grp.attrs[0]));
  	size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);

  	sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
  	if (sect_attrs == NULL)

  		return;
  
  	/* Setup section attributes. */
  	sect_attrs->grp.name = "sections";
  	sect_attrs->grp.attrs = (void *)sect_attrs + size[0];

  	sect_attrs->nsections = 0;

  	sattr = &sect_attrs->attrs[0];
  	gattr = &sect_attrs->grp.attrs[0];
  	for (i = 0; i < nsect; i++) {
  		if (! (sechdrs[i].sh_flags & SHF_ALLOC))
  			continue;
  		sattr->address = sechdrs[i].sh_addr;

  		sattr->name = kstrdup(secstrings + sechdrs[i].sh_name,
  					GFP_KERNEL);
  		if (sattr->name == NULL)
  			goto out;
  		sect_attrs->nsections++;

  		sattr->mattr.show = module_sect_show;
  		sattr->mattr.store = NULL;
  		sattr->mattr.attr.name = sattr->name;

  		sattr->mattr.attr.mode = S_IRUGO;
  		*(gattr++) = &(sattr++)->mattr.attr;
  	}
  	*gattr = NULL;
  
  	if (sysfs_create_group(&mod->mkobj.kobj, &sect_attrs->grp))
  		goto out;
  
  	mod->sect_attrs = sect_attrs;
  	return;
    out:

  	free_sect_attrs(sect_attrs);

  }
  
  static void remove_sect_attrs(struct module *mod)
  {
  	if (mod->sect_attrs) {
  		sysfs_remove_group(&mod->mkobj.kobj,
  				   &mod->sect_attrs->grp);
  		/* We are positive that no one is using any sect attrs
  		 * at this point.  Deallocate immediately. */

  		free_sect_attrs(mod->sect_attrs);

  		mod->sect_attrs = NULL;
  	}
  }

  /*
   * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
   */
  
  struct module_notes_attrs {
  	struct kobject *dir;
  	unsigned int notes;
  	struct bin_attribute attrs[0];
  };
  
  static ssize_t module_notes_read(struct kobject *kobj,
  				 struct bin_attribute *bin_attr,
  				 char *buf, loff_t pos, size_t count)
  {
  	/*
  	 * The caller checked the pos and count against our size.
  	 */
  	memcpy(buf, bin_attr->private + pos, count);
  	return count;
  }
  
  static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
  			     unsigned int i)
  {
  	if (notes_attrs->dir) {
  		while (i-- > 0)
  			sysfs_remove_bin_file(notes_attrs->dir,
  					      &notes_attrs->attrs[i]);

  		kobject_put(notes_attrs->dir);

  	}
  	kfree(notes_attrs);
  }
  
  static void add_notes_attrs(struct module *mod, unsigned int nsect,
  			    char *secstrings, Elf_Shdr *sechdrs)
  {
  	unsigned int notes, loaded, i;
  	struct module_notes_attrs *notes_attrs;
  	struct bin_attribute *nattr;
  
  	/* Count notes sections and allocate structures.  */
  	notes = 0;
  	for (i = 0; i < nsect; i++)
  		if ((sechdrs[i].sh_flags & SHF_ALLOC) &&
  		    (sechdrs[i].sh_type == SHT_NOTE))
  			++notes;
  
  	if (notes == 0)
  		return;
  
  	notes_attrs = kzalloc(sizeof(*notes_attrs)
  			      + notes * sizeof(notes_attrs->attrs[0]),
  			      GFP_KERNEL);
  	if (notes_attrs == NULL)
  		return;
  
  	notes_attrs->notes = notes;
  	nattr = &notes_attrs->attrs[0];
  	for (loaded = i = 0; i < nsect; ++i) {
  		if (!(sechdrs[i].sh_flags & SHF_ALLOC))
  			continue;
  		if (sechdrs[i].sh_type == SHT_NOTE) {
  			nattr->attr.name = mod->sect_attrs->attrs[loaded].name;
  			nattr->attr.mode = S_IRUGO;
  			nattr->size = sechdrs[i].sh_size;
  			nattr->private = (void *) sechdrs[i].sh_addr;
  			nattr->read = module_notes_read;
  			++nattr;
  		}
  		++loaded;
  	}

  	notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);

  	if (!notes_attrs->dir)
  		goto out;
  
  	for (i = 0; i < notes; ++i)
  		if (sysfs_create_bin_file(notes_attrs->dir,
  					  &notes_attrs->attrs[i]))
  			goto out;
  
  	mod->notes_attrs = notes_attrs;
  	return;
  
    out:
  	free_notes_attrs(notes_attrs, i);
  }
  
  static void remove_notes_attrs(struct module *mod)
  {
  	if (mod->notes_attrs)
  		free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
  }

  #else

  static inline void add_sect_attrs(struct module *mod, unsigned int nsect,
  		char *sectstrings, Elf_Shdr *sechdrs)
  {
  }
  
  static inline void remove_sect_attrs(struct module *mod)
  {
  }

  
  static inline void add_notes_attrs(struct module *mod, unsigned int nsect,
  				   char *sectstrings, Elf_Shdr *sechdrs)
  {
  }
  
  static inline void remove_notes_attrs(struct module *mod)
  {
  }

  #endif

  #ifdef CONFIG_SYSFS
  int module_add_modinfo_attrs(struct module *mod)

  {
  	struct module_attribute *attr;

  	struct module_attribute *temp_attr;

  	int error = 0;
  	int i;

  	mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
  					(ARRAY_SIZE(modinfo_attrs) + 1)),
  					GFP_KERNEL);
  	if (!mod->modinfo_attrs)
  		return -ENOMEM;
  
  	temp_attr = mod->modinfo_attrs;

  	for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
  		if (!attr->test ||

  		    (attr->test && attr->test(mod))) {
  			memcpy(temp_attr, attr, sizeof(*temp_attr));

  			error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr);
  			++temp_attr;
  		}

  	}
  	return error;
  }

  void module_remove_modinfo_attrs(struct module *mod)

  {
  	struct module_attribute *attr;
  	int i;

  	for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
  		/* pick a field to test for end of list */
  		if (!attr->attr.name)
  			break;

  		sysfs_remove_file(&mod->mkobj.kobj,&attr->attr);

  		if (attr->free)
  			attr->free(mod);

  	}

  	kfree(mod->modinfo_attrs);

  }

  int mod_sysfs_init(struct module *mod)

  {
  	int err;

  	struct kobject *kobj;

  	if (!module_sysfs_initialized) {
  		printk(KERN_ERR "%s: module sysfs not initialized
  ",

  		       mod->name);
  		err = -EINVAL;
  		goto out;
  	}

  
  	kobj = kset_find_obj(module_kset, mod->name);
  	if (kobj) {
  		printk(KERN_ERR "%s: module is already loaded
  ", mod->name);
  		kobject_put(kobj);
  		err = -EINVAL;
  		goto out;
  	}

  	mod->mkobj.mod = mod;

  	memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
  	mod->mkobj.kobj.kset = module_kset;
  	err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
  				   "%s", mod->name);
  	if (err)
  		kobject_put(&mod->mkobj.kobj);

  	/* delay uevent until full sysfs population */

  out:
  	return err;
  }

  int mod_sysfs_setup(struct module *mod,

  			   struct kernel_param *kparam,
  			   unsigned int num_params)
  {
  	int err;

  	mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);

  	if (!mod->holders_dir) {
  		err = -ENOMEM;

  		goto out_unreg;

  	}

  	err = module_param_sysfs_setup(mod, kparam, num_params);
  	if (err)

  		goto out_unreg_holders;

  	err = module_add_modinfo_attrs(mod);
  	if (err)

  		goto out_unreg_param;

  	kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);

  	return 0;

  out_unreg_param:
  	module_param_sysfs_remove(mod);

  out_unreg_holders:

  	kobject_put(mod->holders_dir);

  out_unreg:

  	kobject_put(&mod->mkobj.kobj);

  	return err;
  }

  
  static void mod_sysfs_fini(struct module *mod)
  {
  	kobject_put(&mod->mkobj.kobj);
  }
  
  #else /* CONFIG_SYSFS */
  
  static void mod_sysfs_fini(struct module *mod)
  {
  }
  
  #endif /* CONFIG_SYSFS */

  
  static void mod_kobject_remove(struct module *mod)
  {

  	module_remove_modinfo_attrs(mod);

  	module_param_sysfs_remove(mod);

  	kobject_put(mod->mkobj.drivers_dir);
  	kobject_put(mod->holders_dir);

  	mod_sysfs_fini(mod);

  }
  
  /*
   * unlink the module with the whole machine is stopped with interrupts off
   * - this defends against kallsyms not taking locks
   */
  static int __unlink_module(void *_mod)
  {
  	struct module *mod = _mod;
  	list_del(&mod->list);
  	return 0;
  }

  /* Free a module, remove from lists, etc (must hold module_mutex). */

  static void free_module(struct module *mod)
  {
  	/* Delete from various lists */

  	stop_machine(__unlink_module, mod, NULL);

  	remove_notes_attrs(mod);

  	remove_sect_attrs(mod);
  	mod_kobject_remove(mod);
  
  	/* Arch-specific cleanup. */
  	module_arch_cleanup(mod);
  
  	/* Module unload stuff */
  	module_unload_free(mod);

  	/* Free any allocated parameters. */
  	destroy_params(mod->kp, mod->num_kp);

  	/* This may be NULL, but that's OK */
  	module_free(mod, mod->module_init);
  	kfree(mod->args);
  	if (mod->percpu)
  		percpu_modfree(mod->percpu);

  #if defined(CONFIG_MODULE_UNLOAD) && defined(CONFIG_SMP)
  	if (mod->refptr)
  		percpu_modfree(mod->refptr);
  #endif

  	/* Free lock-classes: */
  	lockdep_free_key_range(mod->module_core, mod->core_size);

  	/* Finally, free the core (containing the module structure) */
  	module_free(mod, mod->module_core);
  }
  
  void *__symbol_get(const char *symbol)
  {
  	struct module *owner;

  	const struct kernel_symbol *sym;

  	preempt_disable();

  	sym = find_symbol(symbol, &owner, NULL, true, true);
  	if (sym && strong_try_module_get(owner))
  		sym = NULL;

  	preempt_enable();

  	return sym ? (void *)sym->value : NULL;

  }
  EXPORT_SYMBOL_GPL(__symbol_get);

  /*
   * Ensure that an exported symbol [global namespace] does not already exist

   * in the kernel or in some other module's exported symbol table.

   */
  static int verify_export_symbols(struct module *mod)
  {

  	unsigned int i;

  	struct module *owner;

  	const struct kernel_symbol *s;
  	struct {
  		const struct kernel_symbol *sym;
  		unsigned int num;
  	} arr[] = {
  		{ mod->syms, mod->num_syms },
  		{ mod->gpl_syms, mod->num_gpl_syms },
  		{ mod->gpl_future_syms, mod->num_gpl_future_syms },

  #ifdef CONFIG_UNUSED_SYMBOLS

  		{ mod->unused_syms, mod->num_unused_syms },
  		{ mod->unused_gpl_syms, mod->num_unused_gpl_syms },

  #endif

  	};

  	for (i = 0; i < ARRAY_SIZE(arr); i++) {
  		for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {

  			if (find_symbol(s->name, &owner, NULL, true, false)) {

  				printk(KERN_ERR
  				       "%s: exports duplicate symbol %s"
  				       " (owned by %s)
  ",
  				       mod->name, s->name, module_name(owner));
  				return -ENOEXEC;
  			}

  		}

  	}
  	return 0;

  }

  /* Change all symbols so that st_value encodes the pointer directly. */

  static int simplify_symbols(Elf_Shdr *sechdrs,
  			    unsigned int symindex,
  			    const char *strtab,
  			    unsigned int versindex,
  			    unsigned int pcpuindex,
  			    struct module *mod)
  {
  	Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
  	unsigned long secbase;
  	unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
  	int ret = 0;

  	const struct kernel_symbol *ksym;

  
  	for (i = 1; i < n; i++) {
  		switch (sym[i].st_shndx) {
  		case SHN_COMMON:
  			/* We compiled with -fno-common.  These are not
  			   supposed to happen.  */
  			DEBUGP("Common symbol: %s
  ", strtab + sym[i].st_name);
  			printk("%s: please compile with -fno-common
  ",
  			       mod->name);
  			ret = -ENOEXEC;
  			break;
  
  		case SHN_ABS:
  			/* Don't need to do anything */
  			DEBUGP("Absolute symbol: 0x%08lx
  ",
  			       (long)sym[i].st_value);
  			break;
  
  		case SHN_UNDEF:

  			ksym = resolve_symbol(sechdrs, versindex,
  					      strtab + sym[i].st_name, mod);

  			/* Ok if resolved.  */

  			if (ksym) {
  				sym[i].st_value = ksym->value;

  				break;

  			}

  			/* Ok if weak.  */
  			if (ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
  				break;
  
  			printk(KERN_WARNING "%s: Unknown symbol %s
  ",
  			       mod->name, strtab + sym[i].st_name);
  			ret = -ENOENT;
  			break;
  
  		default:
  			/* Divert to percpu allocation if a percpu var. */
  			if (sym[i].st_shndx == pcpuindex)
  				secbase = (unsigned long)mod->percpu;
  			else
  				secbase = sechdrs[sym[i].st_shndx].sh_addr;
  			sym[i].st_value += secbase;
  			break;
  		}
  	}
  
  	return ret;
  }

  /* Additional bytes needed by arch in front of individual sections */
  unsigned int __weak arch_mod_section_prepend(struct module *mod,
  					     unsigned int section)
  {
  	/* default implementation just returns zero */
  	return 0;
  }

  /* Update size with this section: return offset. */

  static long get_offset(struct module *mod, unsigned int *size,
  		       Elf_Shdr *sechdr, unsigned int section)

  {
  	long ret;

  	*size += arch_mod_section_prepend(mod, section);

  	ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
  	*size = ret + sechdr->sh_size;
  	return ret;
  }
  
  /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
     might -- code, read-only data, read-write data, small data.  Tally
     sizes, and place the offsets into sh_entsize fields: high bit means it
     belongs in init. */
  static void layout_sections(struct module *mod,
  			    const Elf_Ehdr *hdr,
  			    Elf_Shdr *sechdrs,
  			    const char *secstrings)
  {
  	static unsigned long const masks[][2] = {
  		/* NOTE: all executable code must be the first section
  		 * in this array; otherwise modify the text_size
  		 * finder in the two loops below */
  		{ SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
  		{ SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
  		{ SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
  		{ ARCH_SHF_SMALL | SHF_ALLOC, 0 }
  	};
  	unsigned int m, i;
  
  	for (i = 0; i < hdr->e_shnum; i++)
  		sechdrs[i].sh_entsize = ~0UL;
  
  	DEBUGP("Core section allocation order:
  ");
  	for (m = 0; m < ARRAY_SIZE(masks); ++m) {
  		for (i = 0; i < hdr->e_shnum; ++i) {
  			Elf_Shdr *s = &sechdrs[i];
  
  			if ((s->sh_flags & masks[m][0]) != masks[m][0]
  			    || (s->sh_flags & masks[m][1])
  			    || s->sh_entsize != ~0UL

  			    || strstarts(secstrings + s->sh_name, ".init"))

  				continue;

  			s->sh_entsize = get_offset(mod, &mod->core_size, s, i);

  			DEBUGP("\t%s
  ", secstrings + s->sh_name);
  		}
  		if (m == 0)
  			mod->core_text_size = mod->core_size;
  	}
  
  	DEBUGP("Init section allocation order:
  ");
  	for (m = 0; m < ARRAY_SIZE(masks); ++m) {
  		for (i = 0; i < hdr->e_shnum; ++i) {
  			Elf_Shdr *s = &sechdrs[i];
  
  			if ((s->sh_flags & masks[m][0]) != masks[m][0]
  			    || (s->sh_flags & masks[m][1])
  			    || s->sh_entsize != ~0UL

  			    || !strstarts(secstrings + s->sh_name, ".init"))

  				continue;

  			s->sh_entsize = (get_offset(mod, &mod->init_size, s, i)

  					 | INIT_OFFSET_MASK);
  			DEBUGP("\t%s
  ", secstrings + s->sh_name);
  		}
  		if (m == 0)
  			mod->init_text_size = mod->init_size;
  	}
  }

  static void set_license(struct module *mod, const char *license)
  {
  	if (!license)
  		license = "unspecified";

  	if (!license_is_gpl_compatible(license)) {

  		if (!test_taint(TAINT_PROPRIETARY_MODULE))

  			printk(KERN_WARNING "%s: module license '%s' taints "

  				"kernel.
  ", mod->name, license);
  		add_taint_module(mod, TAINT_PROPRIETARY_MODULE);

  	}
  }
  
  /* Parse tag=value strings from .modinfo section */
  static char *next_string(char *string, unsigned long *secsize)
  {
  	/* Skip non-zero chars */
  	while (string[0]) {
  		string++;
  		if ((*secsize)-- <= 1)
  			return NULL;
  	}
  
  	/* Skip any zero padding. */
  	while (!string[0]) {
  		string++;
  		if ((*secsize)-- <= 1)
  			return NULL;
  	}
  	return string;
  }
  
  static char *get_modinfo(Elf_Shdr *sechdrs,
  			 unsigned int info,
  			 const char *tag)
  {
  	char *p;
  	unsigned int taglen = strlen(tag);
  	unsigned long size = sechdrs[info].sh_size;
  
  	for (p = (char *)sechdrs[info].sh_addr; p; p = next_string(p, &size)) {
  		if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
  			return p + taglen + 1;
  	}
  	return NULL;
  }

  static void setup_modinfo(struct module *mod, Elf_Shdr *sechdrs,
  			  unsigned int infoindex)
  {
  	struct module_attribute *attr;
  	int i;
  
  	for (i = 0; (attr = modinfo_attrs[i]); i++) {
  		if (attr->setup)
  			attr->setup(mod,
  				    get_modinfo(sechdrs,
  						infoindex,
  						attr->attr.name));
  	}
  }

  #ifdef CONFIG_KALLSYMS

  
  /* lookup symbol in given range of kernel_symbols */
  static const struct kernel_symbol *lookup_symbol(const char *name,
  	const struct kernel_symbol *start,
  	const struct kernel_symbol *stop)
  {
  	const struct kernel_symbol *ks = start;
  	for (; ks < stop; ks++)
  		if (strcmp(ks->name, name) == 0)
  			return ks;
  	return NULL;
  }

  static int is_exported(const char *name, unsigned long value,
  		       const struct module *mod)

  {

  	const struct kernel_symbol *ks;
  	if (!mod)
  		ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab);

  	else

  		ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms);
  	return ks != NULL && ks->value == value;

  }
  
  /* As per nm */
  static char elf_type(const Elf_Sym *sym,
  		     Elf_Shdr *sechdrs,
  		     const char *secstrings,
  		     struct module *mod)
  {
  	if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
  		if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
  			return 'v';
  		else
  			return 'w';
  	}
  	if (sym->st_shndx == SHN_UNDEF)
  		return 'U';
  	if (sym->st_shndx == SHN_ABS)
  		return 'a';
  	if (sym->st_shndx >= SHN_LORESERVE)
  		return '?';
  	if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
  		return 't';
  	if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
  	    && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
  		if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
  			return 'r';
  		else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
  			return 'g';
  		else
  			return 'd';
  	}
  	if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
  		if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
  			return 's';
  		else
  			return 'b';
  	}

  	if (strstarts(secstrings + sechdrs[sym->st_shndx].sh_name, ".debug"))

  		return 'n';
  	return '?';
  }
  
  static void add_kallsyms(struct module *mod,
  			 Elf_Shdr *sechdrs,
  			 unsigned int symindex,
  			 unsigned int strindex,
  			 const char *secstrings)
  {
  	unsigned int i;
  
  	mod->symtab = (void *)sechdrs[symindex].sh_addr;
  	mod->num_symtab = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
  	mod->strtab = (void *)sechdrs[strindex].sh_addr;
  
  	/* Set types up while we still have access to sections. */
  	for (i = 0; i < mod->num_symtab; i++)
  		mod->symtab[i].st_info
  			= elf_type(&mod->symtab[i], sechdrs, secstrings, mod);
  }
  #else
  static inline void add_kallsyms(struct module *mod,
  				Elf_Shdr *sechdrs,
  				unsigned int symindex,
  				unsigned int strindex,
  				const char *secstrings)
  {
  }
  #endif /* CONFIG_KALLSYMS */

  static void dynamic_debug_setup(struct _ddebug *debug, unsigned int num)

  {

  #ifdef CONFIG_DYNAMIC_DEBUG
  	if (ddebug_add_module(debug, num, debug->modname))
  		printk(KERN_ERR "dynamic debug error adding module: %s
  ",
  					debug->modname);
  #endif

  }

  static void *module_alloc_update_bounds(unsigned long size)
  {
  	void *ret = module_alloc(size);
  
  	if (ret) {
  		/* Update module bounds. */
  		if ((unsigned long)ret < module_addr_min)
  			module_addr_min = (unsigned long)ret;
  		if ((unsigned long)ret + size > module_addr_max)
  			module_addr_max = (unsigned long)ret + size;
  	}
  	return ret;
  }

  #ifdef CONFIG_DEBUG_KMEMLEAK
  static void kmemleak_load_module(struct module *mod, Elf_Ehdr *hdr,
  				 Elf_Shdr *sechdrs, char *secstrings)
  {
  	unsigned int i;
  
  	/* only scan the sections containing data */
  	kmemleak_scan_area(mod->module_core, (unsigned long)mod -
  			   (unsigned long)mod->module_core,
  			   sizeof(struct module), GFP_KERNEL);
  
  	for (i = 1; i < hdr->e_shnum; i++) {
  		if (!(sechdrs[i].sh_flags & SHF_ALLOC))
  			continue;
  		if (strncmp(secstrings + sechdrs[i].sh_name, ".data", 5) != 0
  		    && strncmp(secstrings + sechdrs[i].sh_name, ".bss", 4) != 0)
  			continue;
  
  		kmemleak_scan_area(mod->module_core, sechdrs[i].sh_addr -
  				   (unsigned long)mod->module_core,
  				   sechdrs[i].sh_size, GFP_KERNEL);
  	}
  }
  #else
  static inline void kmemleak_load_module(struct module *mod, Elf_Ehdr *hdr,
  					Elf_Shdr *sechdrs, char *secstrings)
  {
  }
  #endif

  /* Allocate and load the module: note that size of section 0 is always
     zero, and we rely on this for optional sections. */

  static noinline struct module *load_module(void __user *umod,

  				  unsigned long len,
  				  const char __user *uargs)
  {
  	Elf_Ehdr *hdr;
  	Elf_Shdr *sechdrs;
  	char *secstrings, *args, *modmagic, *strtab = NULL;

  	char *staging;

  	unsigned int i;
  	unsigned int symindex = 0;
  	unsigned int strindex = 0;

  	unsigned int modindex, versindex, infoindex, pcpuindex;

  	struct module *mod;
  	long err = 0;
  	void *percpu = NULL, *ptr = NULL; /* Stops spurious gcc warning */

  	mm_segment_t old_fs;

  
  	DEBUGP("load_module: umod=%p, len=%lu, uargs=%p
  ",
  	       umod, len, uargs);
  	if (len < sizeof(*hdr))
  		return ERR_PTR(-ENOEXEC);
  
  	/* Suck in entire file: we'll want most of it. */
  	/* vmalloc barfs on "unusual" numbers.  Check here */
  	if (len > 64 * 1024 * 1024 || (hdr = vmalloc(len)) == NULL)
  		return ERR_PTR(-ENOMEM);

  	if (copy_from_user(hdr, umod, len) != 0) {
  		err = -EFAULT;
  		goto free_hdr;
  	}
  
  	/* Sanity checks against insmoding binaries or wrong arch,
             weird elf version */

  	if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0

  	    || hdr->e_type != ET_REL
  	    || !elf_check_arch(hdr)
  	    || hdr->e_shentsize != sizeof(*sechdrs)) {
  		err = -ENOEXEC;
  		goto free_hdr;
  	}
  
  	if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr))
  		goto truncated;
  
  	/* Convenience variables */
  	sechdrs = (void *)hdr + hdr->e_shoff;
  	secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
  	sechdrs[0].sh_addr = 0;
  
  	for (i = 1; i < hdr->e_shnum; i++) {
  		if (sechdrs[i].sh_type != SHT_NOBITS
  		    && len < sechdrs[i].sh_offset + sechdrs[i].sh_size)
  			goto truncated;
  
  		/* Mark all sections sh_addr with their address in the
  		   temporary image. */
  		sechdrs[i].sh_addr = (size_t)hdr + sechdrs[i].sh_offset;
  
  		/* Internal symbols and strings. */
  		if (sechdrs[i].sh_type == SHT_SYMTAB) {
  			symindex = i;
  			strindex = sechdrs[i].sh_link;
  			strtab = (char *)hdr + sechdrs[strindex].sh_offset;
  		}
  #ifndef CONFIG_MODULE_UNLOAD
  		/* Don't load .exit sections */

  		if (strstarts(secstrings+sechdrs[i].sh_name, ".exit"))

  			sechdrs[i].sh_flags &= ~(unsigned long)SHF_ALLOC;
  #endif
  	}
  
  	modindex = find_sec(hdr, sechdrs, secstrings,
  			    ".gnu.linkonce.this_module");
  	if (!modindex) {
  		printk(KERN_WARNING "No module found in object
  ");
  		err = -ENOEXEC;
  		goto free_hdr;
  	}

  	/* This is temporary: point mod into copy of data. */

  	mod = (void *)sechdrs[modindex].sh_addr;
  
  	if (symindex == 0) {
  		printk(KERN_WARNING "%s: module has no symbols (stripped?)
  ",
  		       mod->name);
  		err = -ENOEXEC;
  		goto free_hdr;
  	}

  	versindex = find_sec(hdr, sechdrs, secstrings, "__versions");
  	infoindex = find_sec(hdr, sechdrs, secstrings, ".modinfo");
  	pcpuindex = find_pcpusec(hdr, sechdrs, secstrings);

  	/* Don't keep modinfo and version sections. */

  	sechdrs[infoindex].sh_flags &= ~(unsigned long)SHF_ALLOC;

  	sechdrs[versindex].sh_flags &= ~(unsigned long)SHF_ALLOC;

  #ifdef CONFIG_KALLSYMS
  	/* Keep symbol and string tables for decoding later. */
  	sechdrs[symindex].sh_flags |= SHF_ALLOC;
  	sechdrs[strindex].sh_flags |= SHF_ALLOC;
  #endif
  
  	/* Check module struct version now, before we try to use module. */
  	if (!check_modstruct_version(sechdrs, versindex, mod)) {
  		err = -ENOEXEC;
  		goto free_hdr;
  	}
  
  	modmagic = get_modinfo(sechdrs, infoindex, "vermagic");
  	/* This is allowed: modprobe --force will invalidate it. */
  	if (!modmagic) {

  		err = try_to_force_load(mod, "bad vermagic");

  		if (err)
  			goto free_hdr;

  	} else if (!same_magic(modmagic, vermagic, versindex)) {

  		printk(KERN_ERR "%s: version magic '%s' should be '%s'
  ",
  		       mod->name, modmagic, vermagic);
  		err = -ENOEXEC;
  		goto free_hdr;
  	}

  	staging = get_modinfo(sechdrs, infoindex, "staging");
  	if (staging) {
  		add_taint_module(mod, TAINT_CRAP);
  		printk(KERN_WARNING "%s: module is from the staging directory,"
  		       " the quality is unknown, you have been warned.
  ",
  		       mod->name);
  	}

  	/* Now copy in args */

  	args = strndup_user(uargs, ~0UL >> 1);
  	if (IS_ERR(args)) {
  		err = PTR_ERR(args);

  		goto free_hdr;
  	}

  	if (find_module(mod->name)) {
  		err = -EEXIST;
  		goto free_mod;
  	}
  
  	mod->state = MODULE_STATE_COMING;
  
  	/* Allow arches to frob section contents and sizes.  */
  	err = module_frob_arch_sections(hdr, sechdrs, secstrings, mod);
  	if (err < 0)
  		goto free_mod;
  
  	if (pcpuindex) {
  		/* We have a special allocation for this section. */
  		percpu = percpu_modalloc(sechdrs[pcpuindex].sh_size,

  					 sechdrs[pcpuindex].sh_addralign,
  					 mod->name);

  		if (!percpu) {
  			err = -ENOMEM;

  			goto free_mod;

  		}
  		sechdrs[pcpuindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
  		mod->percpu = percpu;
  	}
  
  	/* Determine total sizes, and put offsets in sh_entsize.  For now
  	   this is done generically; there doesn't appear to be any
  	   special cases for the architectures. */
  	layout_sections(mod, hdr, sechdrs, secstrings);
  
  	/* Do the allocs. */

  	ptr = module_alloc_update_bounds(mod->core_size);

  	/*
  	 * The pointer to this block is stored in the module structure
  	 * which is inside the block. Just mark it as not being a
  	 * leak.
  	 */
  	kmemleak_not_leak(ptr);

  	if (!ptr) {
  		err = -ENOMEM;
  		goto free_percpu;
  	}
  	memset(ptr, 0, mod->core_size);
  	mod->module_core = ptr;

  	ptr = module_alloc_update_bounds(mod->init_size);

  	/*
  	 * The pointer to this block is stored in the module structure
  	 * which is inside the block. This block doesn't need to be
  	 * scanned as it contains data and code that will be freed
  	 * after the module is initialized.
  	 */
  	kmemleak_ignore(ptr);

  	if (!ptr && mod->init_size) {
  		err = -ENOMEM;
  		goto free_core;
  	}
  	memset(ptr, 0, mod->init_size);
  	mod->module_init = ptr;
  
  	/* Transfer each section which specifies SHF_ALLOC */
  	DEBUGP("final section addresses:
  ");
  	for (i = 0; i < hdr->e_shnum; i++) {
  		void *dest;
  
  		if (!(sechdrs[i].sh_flags & SHF_ALLOC))
  			continue;
  
  		if (sechdrs[i].sh_entsize & INIT_OFFSET_MASK)
  			dest = mod->module_init
  				+ (sechdrs[i].sh_entsize & ~INIT_OFFSET_MASK);
  		else
  			dest = mod->module_core + sechdrs[i].sh_entsize;
  
  		if (sechdrs[i].sh_type != SHT_NOBITS)
  			memcpy(dest, (void *)sechdrs[i].sh_addr,
  			       sechdrs[i].sh_size);
  		/* Update sh_addr to point to copy in image. */
  		sechdrs[i].sh_addr = (unsigned long)dest;
  		DEBUGP("\t0x%lx %s
  ", sechdrs[i].sh_addr, secstrings + sechdrs[i].sh_name);
  	}
  	/* Module has been moved. */
  	mod = (void *)sechdrs[modindex].sh_addr;

  	kmemleak_load_module(mod, hdr, sechdrs, secstrings);

  #if defined(CONFIG_MODULE_UNLOAD) && defined(CONFIG_SMP)
  	mod->refptr = percpu_modalloc(sizeof(local_t), __alignof__(local_t),
  				      mod->name);
  	if (!mod->refptr) {
  		err = -ENOMEM;
  		goto free_init;
  	}
  #endif

  	/* Now we've moved module, initialize linked lists, etc. */
  	module_unload_init(mod);

  	/* add kobject, so we can reference it. */

  	err = mod_sysfs_init(mod);
  	if (err)

  		goto free_unload;

  	/* Set up license info based on the info section */
  	set_license(mod, get_modinfo(sechdrs, infoindex, "license"));

  	/*
  	 * ndiswrapper is under GPL by itself, but loads proprietary modules.
  	 * Don't use add_taint_module(), as it would prevent ndiswrapper from
  	 * using GPL-only symbols it needs.
  	 */

  	if (strcmp(mod->name, "ndiswrapper") == 0)

  		add_taint(TAINT_PROPRIETARY_MODULE);
  
  	/* driverloader was caught wrongly pretending to be under GPL */

  	if (strcmp(mod->name, "driverloader") == 0)
  		add_taint_module(mod, TAINT_PROPRIETARY_MODULE);

  	/* Set up MODINFO_ATTR fields */
  	setup_modinfo(mod, sechdrs, infoindex);

  	/* Fix up syms, so that st_value is a pointer to location. */
  	err = simplify_symbols(sechdrs, symindex, strtab, versindex, pcpuindex,
  			       mod);
  	if (err < 0)
  		goto cleanup;

  	/* Now we've got everything in the final locations, we can
  	 * find optional sections. */

  	mod->kp = section_objs(hdr, sechdrs, secstrings, "__param",
  			       sizeof(*mod->kp), &mod->num_kp);

  	mod->syms = section_objs(hdr, sechdrs, secstrings, "__ksymtab",
  				 sizeof(*mod->syms), &mod->num_syms);
  	mod->crcs = section_addr(hdr, sechdrs, secstrings, "__kcrctab");
  	mod->gpl_syms = section_objs(hdr, sechdrs, secstrings, "__ksymtab_gpl",
  				     sizeof(*mod->gpl_syms),
  				     &mod->num_gpl_syms);
  	mod->gpl_crcs = section_addr(hdr, sechdrs, secstrings, "__kcrctab_gpl");
  	mod->gpl_future_syms = section_objs(hdr, sechdrs, secstrings,
  					    "__ksymtab_gpl_future",
  					    sizeof(*mod->gpl_future_syms),
  					    &mod->num_gpl_future_syms);
  	mod->gpl_future_crcs = section_addr(hdr, sechdrs, secstrings,
  					    "__kcrctab_gpl_future");

  #ifdef CONFIG_UNUSED_SYMBOLS

  	mod->unused_syms = section_objs(hdr, sechdrs, secstrings,
  					"__ksymtab_unused",
  					sizeof(*mod->unused_syms),
  					&mod->num_unused_syms);
  	mod->unused_crcs = section_addr(hdr, sechdrs, secstrings,
  					"__kcrctab_unused");
  	mod->unused_gpl_syms = section_objs(hdr, sechdrs, secstrings,
  					    "__ksymtab_unused_gpl",
  					    sizeof(*mod->unused_gpl_syms),
  					    &mod->num_unused_gpl_syms);
  	mod->unused_gpl_crcs = section_addr(hdr, sechdrs, secstrings,
  					    "__kcrctab_unused_gpl");
  #endif

  #ifdef CONFIG_CONSTRUCTORS
  	mod->ctors = section_objs(hdr, sechdrs, secstrings, ".ctors",
  				  sizeof(*mod->ctors), &mod->num_ctors);
  #endif

  
  #ifdef CONFIG_MARKERS
  	mod->markers = section_objs(hdr, sechdrs, secstrings, "__markers",
  				    sizeof(*mod->markers), &mod->num_markers);
  #endif
  #ifdef CONFIG_TRACEPOINTS
  	mod->tracepoints = section_objs(hdr, sechdrs, secstrings,
  					"__tracepoints",
  					sizeof(*mod->tracepoints),
  					&mod->num_tracepoints);

  #endif

  #ifdef CONFIG_EVENT_TRACING
  	mod->trace_events = section_objs(hdr, sechdrs, secstrings,
  					 "_ftrace_events",
  					 sizeof(*mod->trace_events),
  					 &mod->num_trace_events);
  #endif

  #ifdef CONFIG_FTRACE_MCOUNT_RECORD
  	/* sechdrs[0].sh_size is always zero */
  	mod->ftrace_callsites = section_objs(hdr, sechdrs, secstrings,
  					     "__mcount_loc",
  					     sizeof(*mod->ftrace_callsites),
  					     &mod->num_ftrace_callsites);
  #endif

  #ifdef CONFIG_MODVERSIONS

  	if ((mod->num_syms && !mod->crcs)
  	    || (mod->num_gpl_syms && !mod->gpl_crcs)
  	    || (mod->num_gpl_future_syms && !mod->gpl_future_crcs)

  #ifdef CONFIG_UNUSED_SYMBOLS

  	    || (mod->num_unused_syms && !mod->unused_crcs)
  	    || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs)

  #endif
  		) {

  		err = try_to_force_load(mod,
  					"no versions for exported symbols");

  		if (err)
  			goto cleanup;

  	}
  #endif
  
  	/* Now do relocations. */
  	for (i = 1; i < hdr->e_shnum; i++) {
  		const char *strtab = (char *)sechdrs[strindex].sh_addr;
  		unsigned int info = sechdrs[i].sh_info;
  
  		/* Not a valid relocation section? */
  		if (info >= hdr->e_shnum)
  			continue;
  
  		/* Don't bother with non-allocated sections */
  		if (!(sechdrs[info].sh_flags & SHF_ALLOC))
  			continue;
  
  		if (sechdrs[i].sh_type == SHT_REL)
  			err = apply_relocate(sechdrs, strtab, symindex, i,mod);
  		else if (sechdrs[i].sh_type == SHT_RELA)
  			err = apply_relocate_add(sechdrs, strtab, symindex, i,
  						 mod);
  		if (err < 0)
  			goto cleanup;
  	}

          /* Find duplicate symbols */
  	err = verify_export_symbols(mod);

  	if (err < 0)
  		goto cleanup;

    	/* Set up and sort exception table */

  	mod->extable = section_objs(hdr, sechdrs, secstrings, "__ex_table",
  				    sizeof(*mod->extable), &mod->num_exentries);
  	sort_extable(mod->extable, mod->extable + mod->num_exentries);

  
  	/* Finally, copy percpu area over. */
  	percpu_modcopy(mod->percpu, (void *)sechdrs[pcpuindex].sh_addr,
  		       sechdrs[pcpuindex].sh_size);
  
  	add_kallsyms(mod, sechdrs, symindex, strindex, secstrings);

  	if (!mod->taints) {

  		struct _ddebug *debug;

  		unsigned int num_debug;

  		debug = section_objs(hdr, sechdrs, secstrings, "__verbose",
  				     sizeof(*debug), &num_debug);

  		if (debug)
  			dynamic_debug_setup(debug, num_debug);

  	}

  	err = module_finalize(hdr, sechdrs, mod);
  	if (err < 0)
  		goto cleanup;

  	/* flush the icache in correct context */
  	old_fs = get_fs();
  	set_fs(KERNEL_DS);
  
  	/*
  	 * Flush the instruction cache, since we've played with text.
  	 * Do it before processing of module parameters, so the module
  	 * can provide parameter accessor functions of its own.
  	 */
  	if (mod->module_init)
  		flush_icache_range((unsigned long)mod->module_init,
  				   (unsigned long)mod->module_init
  				   + mod->init_size);
  	flush_icache_range((unsigned long)mod->module_core,
  			   (unsigned long)mod->module_core + mod->core_size);
  
  	set_fs(old_fs);

  	mod->args = args;

  	if (section_addr(hdr, sechdrs, secstrings, "__obsparm"))

  		printk(KERN_WARNING "%s: Ignoring obsolete parameters
  ",
  		       mod->name);

  	/* Now sew it into the lists so we can get lockdep and oops

  	 * info during argument parsing.  Noone should access us, since
  	 * strong_try_module_get() will fail.
  	 * lockdep/oops can run asynchronous, so use the RCU list insertion
  	 * function to insert in a way safe to concurrent readers.
  	 * The mutex protects against concurrent writers.
  	 */
  	list_add_rcu(&mod->list, &modules);

  	err = parse_args(mod->name, mod->args, mod->kp, mod->num_kp, NULL);

  	if (err < 0)

  		goto unlink;

  	err = mod_sysfs_setup(mod, mod->kp, mod->num_kp);

  	if (err < 0)

  		goto unlink;

  	add_sect_attrs(mod, hdr->e_shnum, secstrings, sechdrs);

  	add_notes_attrs(mod, hdr->e_shnum, secstrings, sechdrs);

  
  	/* Get rid of temporary copy */
  	vfree(hdr);
  
  	/* Done! */
  	return mod;

   unlink:

  	/* Unlink carefully: kallsyms could be walking list. */
  	list_del_rcu(&mod->list);
  	synchronize_sched();

  	module_arch_cleanup(mod);
   cleanup:

  	kobject_del(&mod->mkobj.kobj);
  	kobject_put(&mod->mkobj.kobj);
   free_unload:

  	module_unload_free(mod);

  #if defined(CONFIG_MODULE_UNLOAD) && defined(CONFIG_SMP)

   free_init:

  	percpu_modfree(mod->refptr);
  #endif

  	module_free(mod, mod->module_init);
   free_core:
  	module_free(mod, mod->module_core);

  	/* mod will be freed with core. Don't access it beyond this line! */

   free_percpu:
  	if (percpu)
  		percpu_modfree(percpu);
   free_mod:
  	kfree(args);
   free_hdr:
  	vfree(hdr);

  	return ERR_PTR(err);

  
   truncated:
  	printk(KERN_ERR "Module len %lu truncated
  ", len);
  	err = -ENOEXEC;
  	goto free_hdr;
  }

  /* Call module constructors. */
  static void do_mod_ctors(struct module *mod)
  {
  #ifdef CONFIG_CONSTRUCTORS
  	unsigned long i;
  
  	for (i = 0; i < mod->num_ctors; i++)
  		mod->ctors[i]();
  #endif
  }

  /* This is where the real work happens */

  SYSCALL_DEFINE3(init_module, void __user *, umod,
  		unsigned long, len, const char __user *, uargs)

  {
  	struct module *mod;
  	int ret = 0;
  
  	/* Must have permission */

  	if (!capable(CAP_SYS_MODULE) || modules_disabled)

  		return -EPERM;
  
  	/* Only one module load at a time, please */

  	if (mutex_lock_interruptible(&module_mutex) != 0)

  		return -EINTR;
  
  	/* Do all the hard work */
  	mod = load_module(umod, len, uargs);
  	if (IS_ERR(mod)) {

  		mutex_unlock(&module_mutex);

  		return PTR_ERR(mod);
  	}

  	/* Drop lock so they can recurse */

  	mutex_unlock(&module_mutex);

  	blocking_notifier_call_chain(&module_notify_list,
  			MODULE_STATE_COMING, mod);

  	do_mod_ctors(mod);

  	/* Start the module */
  	if (mod->init != NULL)

  		ret = do_one_initcall(mod->init);

  	if (ret < 0) {
  		/* Init routine failed: abort.  Try to protect us from
                     buggy refcounters. */
  		mod->state = MODULE_STATE_GOING;

  		synchronize_sched();

  		module_put(mod);

  		blocking_notifier_call_chain(&module_notify_list,
  					     MODULE_STATE_GOING, mod);

  		mutex_lock(&module_mutex);
  		free_module(mod);
  		mutex_unlock(&module_mutex);

  		wake_up(&module_wq);

  		return ret;
  	}

  	if (ret > 0) {

  		printk(KERN_WARNING
  "%s: '%s'->init suspiciously returned %d, it should follow 0/-E convention
  "
  "%s: loading module anyway...
  ",

  		       __func__, mod->name, ret,
  		       __func__);
  		dump_stack();
  	}

  	/* Now it's a first class citizen!  Wake up anyone waiting for it. */

  	mod->state = MODULE_STATE_LIVE;

  	wake_up(&module_wq);

  	blocking_notifier_call_chain(&module_notify_list,
  				     MODULE_STATE_LIVE, mod);

  	/* We need to finish all async code before the module init sequence is done */
  	async_synchronize_full();

  	mutex_lock(&module_mutex);

  	/* Drop initial reference. */
  	module_put(mod);

  	trim_init_extable(mod);

  	module_free(mod, mod->module_init);
  	mod->module_init = NULL;
  	mod->init_size = 0;
  	mod->init_text_size = 0;

  	mutex_unlock(&module_mutex);

  
  	return 0;
  }
  
  static inline int within(unsigned long addr, void *start, unsigned long size)
  {
  	return ((void *)addr >= start && (void *)addr < start + size);
  }
  
  #ifdef CONFIG_KALLSYMS
  /*
   * This ignores the intensely annoying "mapping symbols" found
   * in ARM ELF files: $a, $t and $d.
   */
  static inline int is_arm_mapping_symbol(const char *str)
  {