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/*   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/init.h>#include <linux/kallsyms.h>#include <linux/sysfs.h>#include <linux/kernel.h>#include <linux/slab.h>#include <linux/vmalloc.h>#include <linux/elf.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/unwind.h>#include <asm/uaccess.h>#include <asm/cacheflush.h>#include <linux/license.h>#include <asm/sections.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 * (add/delete uses stop_machine). */static DEFINE_MUTEX(module_mutex);static LIST_HEAD(modules); /* Waiting for a module to finish initializing? */static DECLARE_WAIT_QUEUE_HEAD(module_wq); static BLOCKING_NOTIFIER_HEAD(module_notify_list); 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 |= 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;} /* 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_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 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[];extern const unsigned long __start___kcrctab_unused[];extern const unsigned long __start___kcrctab_unused_gpl[]; #ifndef CONFIG_MODVERSIONS#define symversion(base, idx) NULL#else#define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)#endif /* 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 bool always_ok(bool gplok, bool warn, const char *name){	return true;} static bool printk_unused_warning(bool gplok, bool warn, const char *name){	if (warn) {		printk(KERN_WARNING "Symbol %s is marked as UNUSED, "		       "however this module is using it.\n", name);		printk(KERN_WARNING		       "This symbol will go away in the future.\n");		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.\n");	}	return true;} static bool gpl_only_unused_warning(bool gplok, bool warn, const char *name){	if (!gplok)		return false;	return printk_unused_warning(gplok, warn, name);} static bool gpl_only(bool gplok, bool warn, const char *name){	return gplok;} static bool warn_if_not_gpl(bool gplok, bool warn, const char *name){	if (!gplok && warn) {		printk(KERN_WARNING "Symbol %s is being used "		       "by a non-GPL module, which will not "		       "be allowed in the future\n", name);		printk(KERN_WARNING "Please see the file "		       "Documentation/feature-removal-schedule.txt "		       "in the kernel source tree for more details.\n");	}	return true;} struct symsearch {	const struct kernel_symbol *start, *stop;	const unsigned long *crcs;	bool (*check)(bool gplok, bool warn, const char *name);}; /* Look through this array of symbol tables for a symbol match which * passes the check function. */static const struct kernel_symbol *search_symarrays(const struct symsearch *arr,						    unsigned int num,						    const char *name,						    bool gplok,						    bool warn,						    const unsigned long **crc){	unsigned int i;	const struct kernel_symbol *ks; 	for (i = 0; i < num; i++) {		ks = lookup_symbol(name, arr[i].start, arr[i].stop);		if (!ks || !arr[i].check(gplok, warn, name))			continue; 		if (crc)			*crc = symversion(arr[i].crcs, ks - arr[i].start);		return ks;	}	return NULL;} /* Find a symbol, return value, (optional) crc and (optional) module * which owns it */static unsigned long find_symbol(const char *name,				 struct module **owner,				 const unsigned long **crc,				 bool gplok,				 bool warn){	struct module *mod;	const struct kernel_symbol *ks;	const struct symsearch arr[] = {		{ __start___ksymtab, __stop___ksymtab, __start___kcrctab,		  always_ok },		{ __start___ksymtab_gpl, __stop___ksymtab_gpl,		  __start___kcrctab_gpl, gpl_only },		{ __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,		  __start___kcrctab_gpl_future, warn_if_not_gpl },		{ __start___ksymtab_unused, __stop___ksymtab_unused,		  __start___kcrctab_unused, printk_unused_warning },		{ __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,		  __start___kcrctab_unused_gpl, gpl_only_unused_warning },	}; 	/* Core kernel first. */	ks = search_symarrays(arr, ARRAY_SIZE(arr), name, gplok, warn, crc);	if (ks) {		if (owner)			*owner = NULL;		return ks->value;	} 	/* Now try modules. */	list_for_each_entry(mod, &modules, list) {		struct symsearch arr[] = {			{ mod->syms, mod->syms + mod->num_syms, mod->crcs,			  always_ok },			{ mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,			  mod->gpl_crcs, gpl_only },			{ mod->gpl_future_syms,			  mod->gpl_future_syms + mod->num_gpl_future_syms,			  mod->gpl_future_crcs, warn_if_not_gpl },			{ mod->unused_syms,			  mod->unused_syms + mod->num_unused_syms,			  mod->unused_crcs, printk_unused_warning },			{ mod->unused_gpl_syms,			  mod->unused_gpl_syms + mod->num_unused_gpl_syms,			  mod->unused_gpl_crcs, gpl_only_unused_warning },		}; 		ks = search_symarrays(arr, ARRAY_SIZE(arr),				      name, gplok, warn, crc);		if (ks) {			if (owner)				*owner = mod;			return ks->value;		}	} 	DEBUGP("Failed to find symbol %s\n", name);	return -ENOENT;} /* Search for module by name: must hold module_mutex. */static 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;} #ifdef CONFIG_SMP/* 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; 	if (align > PAGE_SIZE) {		printk(KERN_WARNING "%s: per-cpu alignment %li > %li\n",		       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; 		/* Mark allocated */		pcpu_size[i] = -pcpu_size[i];		return ptr;	} 	printk(KERN_WARNING "Could not allocate %lu bytes percpu data\n",	       size);	return NULL;} static void percpu_modfree(void *freeme){	unsigned int i;	void *ptr = __per_cpu_start + block_size(pcpu_size[0]); 	/* 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:	/* 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 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);} 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.\n");		pcpu_num_used = 1;	} 	return 0;}__initcall(percpu_modinit);#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\n", mod->field);                   \}                                                                     \static int modinfo_##field##_exists(struct module *mod)               \{                                                                     \

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