debug.c

linux-2.4.29操作系统的源码

/*
 * debug_sprintf_exception:
 */

debug_entry_t *debug_sprintf_exception(debug_info_t* id,
                                       int level,char *string,...)
{
	va_list   ap;
	int numargs,alloc_size,idx;
	debug_sprintf_entry *curr_event;
	debug_entry_t *retval = NULL;

	if((!id) || (level > id->level))
		return NULL;
	else {
		numargs=debug_count_numargs(string);
		alloc_size=offsetof(debug_sprintf_entry,args[numargs]);
		curr_event=alloca(alloc_size);

		if(curr_event){
			va_start(ap,string);
			curr_event->string=string;
			for(idx=0;idx<numargs;idx++)
				curr_event->args[idx]=va_arg(ap,long);
			retval=debug_common(id,level, curr_event,alloc_size,1);
			va_end(ap);
		}
		return retval;
	}
}

/*
 * debug_init:
 * - is called exactly once to initialize the debug feature
 */

int debug_init(void)
{
	int rc = 0;

	down(&debug_lock);
	if (!initialized) {
#ifdef CONFIG_PROC_FS
		debug_proc_root_entry =
		    debug_create_proc_dir_entry(&proc_root, DEBUG_DIR_ROOT,
						S_IFDIR | S_IRUGO | S_IXUGO
						| S_IWUSR | S_IWGRP, NULL,
						NULL);
#endif /* CONFIG_PROC_FS */
		printk(KERN_INFO "debug: Initialization complete\n");
		initialized = 1;
	}
	up(&debug_lock);

	return rc;
}

/*
 * debug_register_view:
 */

int debug_register_view(debug_info_t * id, struct debug_view *view)
{
	int rc = 0;
	int i;
	unsigned long flags;
	mode_t mode = S_IFREG;
	struct proc_dir_entry *pde;


	if (!id)
		goto out;
	pde = debug_create_proc_dir_entry(id->proc_root_entry,
					  view->name, mode,
					  &debug_inode_ops,
					  &debug_file_ops);
	if(!pde){
		printk(KERN_WARNING "debug: create_proc_entry() failed! Cannot register view %s/%s\n", id->name,view->name);
		rc = -1;
		goto out;
	}

	spin_lock_irqsave(&id->lock, flags);
	for (i = 0; i < DEBUG_MAX_VIEWS; i++) {
		if (id->views[i] == NULL)
			break;
	}
	if (i == DEBUG_MAX_VIEWS) {
		printk(KERN_WARNING "debug: cannot register view %s/%s\n",
			id->name,view->name);
		printk(KERN_WARNING 
			"debug: maximum number of views reached (%i)!\n", i);
		debug_delete_proc_dir_entry(id->proc_root_entry, pde);
		
		rc = -1;
	}
	else {
		id->views[i] = view;
		if (view->prolog_proc || view->format_proc || view->header_proc)
			mode |= S_IRUSR;
		if (view->input_proc)
			mode |= S_IWUSR;
		id->proc_entries[i] = pde;
		rc = 0;
	}
	spin_unlock_irqrestore(&id->lock, flags);
      out:
	return rc;
}

/*
 * debug_unregister_view:
 */

int debug_unregister_view(debug_info_t * id, struct debug_view *view)
{
	int rc = 0;
	int i;
	unsigned long flags;

	if (!id)
		goto out;
	spin_lock_irqsave(&id->lock, flags);
	for (i = 0; i < DEBUG_MAX_VIEWS; i++) {
		if (id->views[i] == view)
			break;
	}
	if (i == DEBUG_MAX_VIEWS)
		rc = -1;
	else {
		debug_delete_proc_dir_entry(id->proc_root_entry,
					    id->proc_entries[i]);		
		id->views[i] = NULL;
		rc = 0;
	}
	spin_unlock_irqrestore(&id->lock, flags);
      out:
	return rc;
}

/*
 * functions for debug-views
 ***********************************
*/

/*
 * prints out actual debug level
 */

static int debug_prolog_level_fn(debug_info_t * id,
				 struct debug_view *view, char *out_buf)
{
	int rc = 0;

	if(id->level == -1) rc = sprintf(out_buf,"-\n");
	else rc = sprintf(out_buf, "%i\n", id->level);
	return rc;
}

/*
 * reads new debug level
 */

static int debug_input_level_fn(debug_info_t * id, struct debug_view *view,
				struct file *file, const char *user_buf,
				size_t in_buf_size, loff_t * offset)
{
	char input_buf[1];
	int rc = in_buf_size;

	if (*offset != 0)
		goto out;
	if (copy_from_user(input_buf, user_buf, 1)){
		rc = -EFAULT;
		goto out;
	}
	if (isdigit(input_buf[0])) {
		int new_level = ((int) input_buf[0] - (int) '0');
		debug_set_level(id, new_level);
	} else if(input_buf[0] == '-') {
		debug_set_level(id, DEBUG_OFF_LEVEL);
	} else {
		printk(KERN_INFO "debug: level `%c` is not valid\n",
		       input_buf[0]);
	}
      out:
	*offset = in_buf_size;
	return rc;		/* number of input characters */
}


/*
 * flushes debug areas
 */
 
void debug_flush(debug_info_t* id, int area)
{
        unsigned long flags;
        int i;

        if(!id)
                return;
        spin_lock_irqsave(&id->lock,flags);
        if(area == DEBUG_FLUSH_ALL){
                id->active_area = 0;
                memset(id->active_entry, 0, id->nr_areas * sizeof(int));
                for (i = 0; i < id->nr_areas; i++) 
                        memset(id->areas[i], 0, PAGE_SIZE << id->page_order);
                printk(KERN_INFO "debug: %s: all areas flushed\n",id->name);
        } else if(area >= 0 && area < id->nr_areas) {
                id->active_entry[area] = 0;
                memset(id->areas[area], 0, PAGE_SIZE << id->page_order);
                printk(KERN_INFO
                        "debug: %s: area %i has been flushed\n",
                        id->name, area);
        } else {
                printk(KERN_INFO
                        "debug: %s: area %i cannot be flushed (range: %i - %i)\n",
                        id->name, area, 0, id->nr_areas-1);
        }
        spin_unlock_irqrestore(&id->lock,flags);
}

/*
 * view function: flushes debug areas 
 */
 
static int debug_input_flush_fn(debug_info_t * id, struct debug_view *view,
                                struct file *file, const char *user_buf,
                                size_t in_buf_size, loff_t * offset)
{
        char input_buf[1];
        int rc = in_buf_size;
 
        if (*offset != 0)
                goto out;
        if (copy_from_user(input_buf, user_buf, 1)){
                rc = -EFAULT;
                goto out;
        }
        if(input_buf[0] == '-') { 
                debug_flush(id, DEBUG_FLUSH_ALL);
                goto out;
        }
        if (isdigit(input_buf[0])) {
                int area = ((int) input_buf[0] - (int) '0');
                debug_flush(id, area);
                goto out;
        }

        printk(KERN_INFO "debug: area `%c` is not valid\n", input_buf[0]);

      out:
        *offset = in_buf_size;
        return rc;              /* number of input characters */
}

/*
 * prints debug header in raw format
 */

int debug_raw_header_fn(debug_info_t * id, struct debug_view *view,
                         int area, debug_entry_t * entry, char *out_buf)
{
        int rc;

	rc = sizeof(debug_entry_t);
	memcpy(out_buf,entry,sizeof(debug_entry_t));
        return rc;
}

/*
 * prints debug data in raw format
 */

static int debug_raw_format_fn(debug_info_t * id, struct debug_view *view,
			       char *out_buf, const char *in_buf)
{
	int rc;

	rc = id->buf_size;
	memcpy(out_buf, in_buf, id->buf_size);
	return rc;
}

/*
 * prints debug data in hex/ascii format
 */

static int debug_hex_ascii_format_fn(debug_info_t * id, struct debug_view *view,
		    		  char *out_buf, const char *in_buf)
{
	int i, rc = 0;

	for (i = 0; i < id->buf_size; i++) {
                rc += sprintf(out_buf + rc, "%02x ",
                              ((unsigned char *) in_buf)[i]);
        }
	rc += sprintf(out_buf + rc, "| ");
	for (i = 0; i < id->buf_size; i++) {
		unsigned char c = in_buf[i];
		if (!isprint(c))
			rc += sprintf(out_buf + rc, ".");
		else
			rc += sprintf(out_buf + rc, "%c", c);
	}
	rc += sprintf(out_buf + rc, "\n");
	return rc;
}

/*
 * prints header for debug entry
 */

int debug_dflt_header_fn(debug_info_t * id, struct debug_view *view,
			 int area, debug_entry_t * entry, char *out_buf)
{
	struct timeval time_val;
	unsigned long long time;
	char *except_str;
	unsigned long caller;
	int rc = 0;
	unsigned int level;

	level = entry->id.fields.level;
	time = entry->id.stck;
	/* adjust todclock to 1970 */
	time -= 0x8126d60e46000000LL - (0x3c26700LL * 1000000 * 4096);
	tod_to_timeval(time, &time_val);

	if (entry->id.fields.exception)
		except_str = "*";
	else
		except_str = "-";
	caller = (unsigned long) entry->caller;
#if defined(CONFIG_ARCH_S390X)
	rc += sprintf(out_buf, "%02i %011lu:%06lu %1u %1s %02i %016lx  ",
		      area, time_val.tv_sec, time_val.tv_usec, level,
		      except_str, entry->id.fields.cpuid, caller);
#else
	caller &= 0x7fffffff;
	rc += sprintf(out_buf, "%02i %011lu:%06lu %1u %1s %02i %08lx  ",
		      area, time_val.tv_sec, time_val.tv_usec, level,
		      except_str, entry->id.fields.cpuid, caller);
#endif
	return rc;
}

/*
 * prints debug data sprintf-formated:
 * debug_sprinf_event/exception calls must be used together with this view
 */

#define DEBUG_SPRINTF_MAX_ARGS 10

int debug_sprintf_format_fn(debug_info_t * id, struct debug_view *view,
                            char *out_buf, debug_sprintf_entry *curr_event)
{
	int num_longs, num_used_args = 0,i, rc = 0;
	int index[DEBUG_SPRINTF_MAX_ARGS];

	/* count of longs fit into one entry */
	num_longs = id->buf_size /  sizeof(long); 

	if(num_longs < 1)
		goto out; /* bufsize of entry too small */
	if(num_longs == 1) {
		/* no args, we use only the string */
		strcpy(out_buf, curr_event->string);
		rc = strlen(curr_event->string);
		goto out;
	}

	/* number of arguments used for sprintf (without the format string) */
	num_used_args   = MIN(DEBUG_SPRINTF_MAX_ARGS, (num_longs - 1));

	memset(index,0, DEBUG_SPRINTF_MAX_ARGS * sizeof(int));

	for(i = 0; i < num_used_args; i++)
		index[i] = i;

	rc =  sprintf(out_buf, curr_event->string, curr_event->args[index[0]],
		curr_event->args[index[1]], curr_event->args[index[2]],
		curr_event->args[index[3]], curr_event->args[index[4]],
		curr_event->args[index[5]], curr_event->args[index[6]],
		curr_event->args[index[7]], curr_event->args[index[8]],
		curr_event->args[index[9]]);

out:

	return rc;
}

/*
 * init_module:
 */

#ifdef MODULE
int init_module(void)
{
	int rc = 0;
#ifdef DEBUG
	printk("debug_module_init: \n");
#endif
	rc = debug_init();
	if (rc) 
		printk(KERN_INFO "debug: an error occurred with debug_init\n");
	return rc;
}

/*
 * cleanup_module:
 */

void cleanup_module(void)
{
#ifdef DEBUG
	printk("debug_cleanup_module: \n");
#endif
#ifdef CONFIG_PROC_FS
	debug_delete_proc_dir_entry(&proc_root, debug_proc_root_entry);
#endif /* CONFIG_PROC_FS */
	return;
}

#endif			/* MODULE */

EXPORT_SYMBOL(debug_register);
EXPORT_SYMBOL(debug_unregister); 
EXPORT_SYMBOL(debug_set_level);
EXPORT_SYMBOL(debug_register_view);
EXPORT_SYMBOL(debug_unregister_view);
EXPORT_SYMBOL(debug_event_common);
EXPORT_SYMBOL(debug_exception_common);
EXPORT_SYMBOL(debug_hex_ascii_view);
EXPORT_SYMBOL(debug_raw_view);
EXPORT_SYMBOL(debug_dflt_header_fn);
EXPORT_SYMBOL(debug_sprintf_view);
EXPORT_SYMBOL(debug_sprintf_exception);
EXPORT_SYMBOL(debug_sprintf_event);