#ifndef __ASM_SPINLOCK_H #define __ASM_SPINLOCK_H #include #include #include #include typedef struct { volatile s16 lock; s8 recurse_cpu; u8 recurse_cnt; } spinlock_t; #define SPIN_LOCK_UNLOCKED /*(spinlock_t)*/ { 1, -1, 0 } #define spin_lock_init(x) do { *(x) = (spinlock_t) SPIN_LOCK_UNLOCKED; } while(0) #define spin_is_locked(x) (*(volatile char *)(&(x)->lock) <= 0) static inline void _raw_spin_lock(spinlock_t *lock) { __asm__ __volatile__ ( "1: lock; decb %0 \n" " js 2f \n" ".section .text.lock,\"ax\"\n" "2: cmpb $0,%0 \n" " rep; nop \n" " jle 2b \n" " jmp 1b \n" ".previous" : "=m" (lock->lock) : : "memory" ); } static inline void _raw_spin_unlock(spinlock_t *lock) { ASSERT(spin_is_locked(lock)); __asm__ __volatile__ ( "movb $1,%0" : "=m" (lock->lock) : : "memory" ); } static inline int _raw_spin_trylock(spinlock_t *lock) { char oldval; __asm__ __volatile__( "xchgb %b0,%1" :"=q" (oldval), "=m" (lock->lock) :"0" (0) : "memory"); return oldval > 0; } /* * spin_[un]lock_recursive(): Use these forms when the lock can (safely!) be * reentered recursively on the same CPU. All critical regions that may form * part of a recursively-nested set must be protected by these forms. If there * are any critical regions that cannot form part of such a set, they can use * standard spin_[un]lock(). */ #define _raw_spin_lock_recursive(_lock) \ do { \ int cpu = smp_processor_id(); \ if ( likely((_lock)->recurse_cpu != cpu) ) \ { \ spin_lock(_lock); \ (_lock)->recurse_cpu = cpu; \ } \ (_lock)->recurse_cnt++; \ } while ( 0 ) #define _raw_spin_unlock_recursive(_lock) \ do { \ if ( likely(--(_lock)->recurse_cnt == 0) ) \ { \ (_lock)->recurse_cpu = -1; \ spin_unlock(_lock); \ } \ } while ( 0 ) typedef struct { volatile unsigned int lock; } rwlock_t; #define RW_LOCK_UNLOCKED /*(rwlock_t)*/ { RW_LOCK_BIAS } #define rwlock_init(x) do { *(x) = (rwlock_t) RW_LOCK_UNLOCKED; } while(0) /* * On x86, we implement read-write locks as a 32-bit counter * with the high bit (sign) being the "contended" bit. */ static inline void _raw_read_lock(rwlock_t *rw) { __build_read_lock(rw, "__read_lock_failed"); } static inline void _raw_write_lock(rwlock_t *rw) { __build_write_lock(rw, "__write_lock_failed"); } #define _raw_read_unlock(rw) \ __asm__ __volatile__ ( \ "lock ; incl %0" : \ "=m" ((rw)->lock) : : "memory" ) #define _raw_write_unlock(rw) \ __asm__ __volatile__ ( \ "lock ; addl $" RW_LOCK_BIAS_STR ",%0" : \ "=m" ((rw)->lock) : : "memory" ) #endif /* __ASM_SPINLOCK_H */ c?id=8e12b39d5dc565df2780f46f615129885439d5fa'>src/patch-cmdline.c
blob: 571f848d81c505c42be176a6150768929debab67 (plain) 
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/*
 * patch-cmdline.c - patch the kernel command line on rb532
 *
 * Copyright (C) 2006 Felix Fietkau <nbd@openwrt.org>
 *
 * 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 <stdio.h>
#include <stdlib.h>
#include <stddef.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <string.h>

#define SEARCH_SPACE	(16 * 1024)
#define CMDLINE_MAX		512

int main(int argc, char **argv)
{
	int fd, found = 0, len, ret = -1;
	char *ptr, *p;

	if (argc != 3) {
		fprintf(stderr, "Usage: %s <file> <cmdline>\n", argv[0]);
		goto err1;
	}
	len = strlen(argv[2]);
	if (len + 9 > CMDLINE_MAX) {
		fprintf(stderr, "Command line string too long\n");
		goto err1;
	}
	
	if (((fd = open(argv[1], O_RDWR)) < 0) ||
		(ptr = (char *) mmap(0, SEARCH_SPACE + CMDLINE_MAX, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0)) == (void *) (-1)) {
		fprintf(stderr, "Could not open kernel image");
		goto err2;
	}
	
	for (p = ptr; p < (ptr + SEARCH_SPACE); p += 4) {
		if (memcmp(p, "CMDLINE:", 8) == 0) {
			found = 1;
			p += 8;
			break;
		}
	}
	if (!found) {
		fprintf(stderr, "Command line marker not found!\n");
		goto err3;
	}

	memset(p, 0, CMDLINE_MAX - 8);
	strcpy(p, argv[2]);
	msync(p, CMDLINE_MAX, MS_SYNC|MS_INVALIDATE);
	ret = 0;

err3:
	munmap((void *) ptr, len);
err2:
	if (fd > 0)
		close(fd);
err1:
	return ret;
}
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