Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
diff --git a/arch/s390/kernel/debug.c b/arch/s390/kernel/debug.c
new file mode 100644
index 0000000..91f8ce5
--- /dev/null
+++ b/arch/s390/kernel/debug.c
@@ -0,0 +1,1286 @@
+/*
+ *  arch/s390/kernel/debug.c
+ *   S/390 debug facility
+ *
+ *    Copyright (C) 1999, 2000 IBM Deutschland Entwicklung GmbH,
+ *                             IBM Corporation
+ *    Author(s): Michael Holzheu (holzheu@de.ibm.com),
+ *               Holger Smolinski (Holger.Smolinski@de.ibm.com)
+ *
+ *    Bugreports to: <Linux390@de.ibm.com>
+ */
+
+#include <linux/config.h>
+#include <linux/stddef.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/slab.h>
+#include <linux/ctype.h>
+#include <linux/sysctl.h>
+#include <asm/uaccess.h>
+#include <asm/semaphore.h>
+
+#include <linux/module.h>
+#include <linux/init.h>
+
+#include <asm/debug.h>
+
+#define DEBUG_PROLOG_ENTRY -1
+
+/* typedefs */
+
+typedef struct file_private_info {
+	loff_t offset;			/* offset of last read in file */
+	int    act_area;                /* number of last formated area */
+	int    act_entry;               /* last formated entry (offset */
+                                        /* relative to beginning of last */
+                                        /* formated area) */ 
+	size_t act_entry_offset;        /* up to this offset we copied */
+					/* in last read the last formated */
+					/* entry to userland */
+	char   temp_buf[2048];		/* buffer for output */
+	debug_info_t *debug_info_org;   /* original debug information */
+	debug_info_t *debug_info_snap;	/* snapshot of debug information */
+	struct debug_view *view;	/* used view of debug info */
+} file_private_info_t;
+
+typedef struct
+{
+	char *string;
+	/* 
+	 * This assumes that all args are converted into longs 
+	 * on L/390 this is the case for all types of parameter 
+	 * except of floats, and long long (32 bit) 
+         *
+         */
+	long args[0];
+} debug_sprintf_entry_t;
+
+
+extern void tod_to_timeval(uint64_t todval, struct timeval *xtime);
+
+/* internal function prototyes */
+
+static int debug_init(void);
+static ssize_t debug_output(struct file *file, char __user *user_buf,
+			    size_t user_len, loff_t * offset);
+static ssize_t debug_input(struct file *file, const char __user *user_buf,
+			   size_t user_len, loff_t * offset);
+static int debug_open(struct inode *inode, struct file *file);
+static int debug_close(struct inode *inode, struct file *file);
+static debug_info_t*  debug_info_create(char *name, int page_order, int nr_areas, int buf_size);
+static void debug_info_get(debug_info_t *);
+static void debug_info_put(debug_info_t *);
+static int debug_prolog_level_fn(debug_info_t * id,
+				 struct debug_view *view, char *out_buf);
+static int debug_input_level_fn(debug_info_t * id, struct debug_view *view,
+				struct file *file, const char __user *user_buf,
+				size_t user_buf_size, loff_t * offset);
+static int debug_input_flush_fn(debug_info_t * id, struct debug_view *view,
+                                struct file *file, const char __user *user_buf,
+                                size_t user_buf_size, loff_t * offset);
+static int debug_hex_ascii_format_fn(debug_info_t * id, struct debug_view *view,
+                                char *out_buf, const char *in_buf);
+static int debug_raw_format_fn(debug_info_t * id,
+				 struct debug_view *view, char *out_buf,
+				 const char *in_buf);
+static int debug_raw_header_fn(debug_info_t * id, struct debug_view *view,
+                         int area, debug_entry_t * entry, char *out_buf);
+
+static int debug_sprintf_format_fn(debug_info_t * id, struct debug_view *view,
+				   char *out_buf, debug_sprintf_entry_t *curr_event);
+
+/* globals */
+
+struct debug_view debug_raw_view = {
+	"raw",
+	NULL,
+	&debug_raw_header_fn,
+	&debug_raw_format_fn,
+	NULL,
+	NULL
+};
+
+struct debug_view debug_hex_ascii_view = {
+	"hex_ascii",
+	NULL,
+	&debug_dflt_header_fn,
+	&debug_hex_ascii_format_fn,
+	NULL,
+	NULL
+};
+
+struct debug_view debug_level_view = {
+	"level",
+	&debug_prolog_level_fn,
+	NULL,
+	NULL,
+	&debug_input_level_fn,
+	NULL
+};
+
+struct debug_view debug_flush_view = {
+        "flush",
+        NULL,
+        NULL,
+        NULL,
+        &debug_input_flush_fn,
+        NULL
+};
+
+struct debug_view debug_sprintf_view = {
+	"sprintf",
+	NULL,
+	&debug_dflt_header_fn,
+	(debug_format_proc_t*)&debug_sprintf_format_fn,
+	NULL,
+	NULL
+};
+
+
+unsigned int debug_feature_version = __DEBUG_FEATURE_VERSION;
+
+/* static globals */
+
+static debug_info_t *debug_area_first = NULL;
+static debug_info_t *debug_area_last = NULL;
+DECLARE_MUTEX(debug_lock);
+
+static int initialized;
+
+static struct file_operations debug_file_ops = {
+	.owner	 = THIS_MODULE,
+	.read    = debug_output,
+	.write   = debug_input,	
+	.open    = debug_open,
+	.release = debug_close,
+};
+
+static struct proc_dir_entry *debug_proc_root_entry;
+
+/* functions */
+
+/*
+ * debug_info_alloc
+ * - alloc new debug-info
+ */
+
+static debug_info_t*  debug_info_alloc(char *name, int page_order,
+                                        int nr_areas, int buf_size)
+{
+	debug_info_t* rc;
+	int i;
+
+	/* alloc everything */
+
+	rc = (debug_info_t*) kmalloc(sizeof(debug_info_t), GFP_ATOMIC);
+	if(!rc)
+		goto fail_malloc_rc;
+	rc->active_entry = (int*)kmalloc(nr_areas * sizeof(int), GFP_ATOMIC);
+	if(!rc->active_entry)
+		goto fail_malloc_active_entry;
+	memset(rc->active_entry, 0, nr_areas * sizeof(int));
+	rc->areas = (debug_entry_t **) kmalloc(nr_areas *
+						sizeof(debug_entry_t *),
+						GFP_ATOMIC);
+	if (!rc->areas)
+		goto fail_malloc_areas;
+	for (i = 0; i < nr_areas; i++) {
+		rc->areas[i] = (debug_entry_t *) __get_free_pages(GFP_ATOMIC,
+								page_order);
+		if (!rc->areas[i]) {
+			for (i--; i >= 0; i--) {
+				free_pages((unsigned long) rc->areas[i],
+						page_order);
+			}
+			goto fail_malloc_areas2;
+		} else {
+			memset(rc->areas[i], 0, PAGE_SIZE << page_order);
+		}
+	}
+
+	/* initialize members */
+
+	spin_lock_init(&rc->lock);
+	rc->page_order  = page_order;
+	rc->nr_areas    = nr_areas;
+	rc->active_area = 0;
+	rc->level       = DEBUG_DEFAULT_LEVEL;
+	rc->buf_size    = buf_size;
+	rc->entry_size  = sizeof(debug_entry_t) + buf_size;
+	strlcpy(rc->name, name, sizeof(rc->name));
+	memset(rc->views, 0, DEBUG_MAX_VIEWS * sizeof(struct debug_view *));
+#ifdef CONFIG_PROC_FS
+	memset(rc->proc_entries, 0 ,DEBUG_MAX_VIEWS *
+		sizeof(struct proc_dir_entry*));
+#endif /* CONFIG_PROC_FS */
+	atomic_set(&(rc->ref_count), 0);
+
+	return rc;
+
+fail_malloc_areas2:
+	kfree(rc->areas);
+fail_malloc_areas:
+	kfree(rc->active_entry);
+fail_malloc_active_entry:
+	kfree(rc);
+fail_malloc_rc:
+	return NULL;
+}
+
+/*
+ * debug_info_free
+ * - free memory debug-info
+ */
+
+static void debug_info_free(debug_info_t* db_info){
+	int i;
+	for (i = 0; i < db_info->nr_areas; i++) {
+		free_pages((unsigned long) db_info->areas[i],
+		db_info->page_order);
+	}
+	kfree(db_info->areas);
+	kfree(db_info->active_entry);
+	kfree(db_info);
+}
+
+/*
+ * debug_info_create
+ * - create new debug-info
+ */
+
+static debug_info_t*  debug_info_create(char *name, int page_order, 
+                                        int nr_areas, int buf_size)
+{
+	debug_info_t* rc;
+
+        rc = debug_info_alloc(name, page_order, nr_areas, buf_size);
+        if(!rc) 
+		goto out;
+
+
+	/* create proc rood directory */
+        rc->proc_root_entry = proc_mkdir(rc->name, debug_proc_root_entry);
+
+	/* append new element to linked list */
+        if (debug_area_first == NULL) {
+                /* first element in list */
+                debug_area_first = rc;
+                rc->prev = NULL;
+        } else {
+                /* append element to end of list */
+                debug_area_last->next = rc;
+                rc->prev = debug_area_last;
+        }
+        debug_area_last = rc;
+        rc->next = NULL;
+
+	debug_info_get(rc);
+out:
+	return rc;
+}
+
+/*
+ * debug_info_copy
+ * - copy debug-info
+ */
+
+static debug_info_t* debug_info_copy(debug_info_t* in)
+{
+        int i;
+        debug_info_t* rc;
+        rc = debug_info_alloc(in->name, in->page_order, 
+                                in->nr_areas, in->buf_size);
+        if(!rc)
+                goto out;
+
+        for(i = 0; i < in->nr_areas; i++){
+                memcpy(rc->areas[i],in->areas[i], PAGE_SIZE << in->page_order);
+        }
+out:
+        return rc;
+}
+
+/*
+ * debug_info_get
+ * - increments reference count for debug-info
+ */
+
+static void debug_info_get(debug_info_t * db_info)
+{
+	if (db_info)
+		atomic_inc(&db_info->ref_count);
+}
+
+/*
+ * debug_info_put:
+ * - decreases reference count for debug-info and frees it if necessary
+ */
+
+static void debug_info_put(debug_info_t *db_info)
+{
+	int i;
+
+	if (!db_info)
+		return;
+	if (atomic_dec_and_test(&db_info->ref_count)) {
+#ifdef DEBUG
+		printk(KERN_INFO "debug: freeing debug area %p (%s)\n",
+		       db_info, db_info->name);
+#endif
+		for (i = 0; i < DEBUG_MAX_VIEWS; i++) {
+			if (db_info->views[i] == NULL)
+				continue;
+#ifdef CONFIG_PROC_FS
+			remove_proc_entry(db_info->proc_entries[i]->name,
+					  db_info->proc_root_entry);
+#endif
+		}
+#ifdef CONFIG_PROC_FS
+		remove_proc_entry(db_info->proc_root_entry->name,
+				  debug_proc_root_entry);
+#endif
+		if(db_info == debug_area_first)
+			debug_area_first = db_info->next;
+		if(db_info == debug_area_last)
+			debug_area_last = db_info->prev;
+		if(db_info->prev) db_info->prev->next = db_info->next;
+		if(db_info->next) db_info->next->prev = db_info->prev;
+		debug_info_free(db_info);
+	}
+}
+
+/*
+ * debug_format_entry:
+ * - format one debug entry and return size of formated data
+ */
+
+static int debug_format_entry(file_private_info_t *p_info)
+{
+	debug_info_t *id_org    = p_info->debug_info_org;
+	debug_info_t *id_snap   = p_info->debug_info_snap;
+	struct debug_view *view = p_info->view;
+	debug_entry_t *act_entry;
+	size_t len = 0;
+	if(p_info->act_entry == DEBUG_PROLOG_ENTRY){
+		/* print prolog */
+        	if (view->prolog_proc)
+                	len += view->prolog_proc(id_org, view,p_info->temp_buf);
+		goto out;
+	}
+
+	act_entry = (debug_entry_t *) ((char*)id_snap->areas[p_info->act_area] +
+					p_info->act_entry);
+                        
+	if (act_entry->id.stck == 0LL)
+			goto out;  /* empty entry */
+	if (view->header_proc)
+		len += view->header_proc(id_org, view, p_info->act_area, 
+					act_entry, p_info->temp_buf + len);
+	if (view->format_proc)
+		len += view->format_proc(id_org, view, p_info->temp_buf + len,
+						DEBUG_DATA(act_entry));
+      out:
+        return len;
+}
+
+/*
+ * debug_next_entry:
+ * - goto next entry in p_info
+ */
+
+extern inline int debug_next_entry(file_private_info_t *p_info)
+{
+	debug_info_t *id = p_info->debug_info_snap;
+	if(p_info->act_entry == DEBUG_PROLOG_ENTRY){
+		p_info->act_entry = 0;
+		goto out;
+	}
+	if ((p_info->act_entry += id->entry_size)
+		> ((PAGE_SIZE << (id->page_order)) 
+		- id->entry_size)){
+
+		/* next area */
+		p_info->act_entry = 0;
+        	p_info->act_area++;
+        	if(p_info->act_area >= id->nr_areas)
+			return 1;
+	}
+out:
+	return 0;	
+}
+
+/*
+ * debug_output:
+ * - called for user read()
+ * - copies formated debug entries to the user buffer
+ */
+
+static ssize_t debug_output(struct file *file,		/* file descriptor */
+			    char __user *user_buf,	/* user buffer */
+			    size_t  len,		/* length of buffer */
+			    loff_t *offset)	      /* offset in the file */
+{
+	size_t count = 0;
+	size_t entry_offset, size = 0;
+	file_private_info_t *p_info;
+
+	p_info = ((file_private_info_t *) file->private_data);
+	if (*offset != p_info->offset) 
+		return -EPIPE;
+	if(p_info->act_area >= p_info->debug_info_snap->nr_areas)
+		return 0;
+
+	entry_offset = p_info->act_entry_offset;
+
+	while(count < len){
+		size = debug_format_entry(p_info);
+		size = min((len - count), (size - entry_offset));
+
+		if(size){
+			if (copy_to_user(user_buf + count, 
+					p_info->temp_buf + entry_offset, size))
+			return -EFAULT;
+		}
+		count += size;
+		entry_offset = 0;
+		if(count != len)
+			if(debug_next_entry(p_info)) 
+				goto out;
+	}
+out:
+	p_info->offset           = *offset + count;
+	p_info->act_entry_offset = size;	
+	*offset = p_info->offset;
+	return count;
+}
+
+/*
+ * debug_input:
+ * - called for user write()
+ * - calls input function of view
+ */
+
+static ssize_t debug_input(struct file *file,
+			   const char __user *user_buf, size_t length,
+			   loff_t *offset)
+{
+	int rc = 0;
+	file_private_info_t *p_info;
+
+	down(&debug_lock);
+	p_info = ((file_private_info_t *) file->private_data);
+	if (p_info->view->input_proc)
+		rc = p_info->view->input_proc(p_info->debug_info_org,
+					      p_info->view, file, user_buf,
+					      length, offset);
+	else
+		rc = -EPERM;
+	up(&debug_lock);
+	return rc;		/* number of input characters */
+}
+
+/*
+ * debug_open:
+ * - called for user open()
+ * - copies formated output to private_data area of the file
+ *   handle
+ */
+
+static int debug_open(struct inode *inode, struct file *file)
+{
+	int i = 0, rc = 0;
+	file_private_info_t *p_info;
+	debug_info_t *debug_info, *debug_info_snapshot;
+
+#ifdef DEBUG
+	printk("debug_open\n");
+#endif
+	down(&debug_lock);
+
+	/* find debug log and view */
+
+	debug_info = debug_area_first;
+	while(debug_info != NULL){
+		for (i = 0; i < DEBUG_MAX_VIEWS; i++) {
+			if (debug_info->views[i] == NULL)
+				continue;
+			else if (debug_info->proc_entries[i] ==
+				 PDE(file->f_dentry->d_inode)) {
+				goto found;	/* found view ! */
+			}
+		}
+		debug_info = debug_info->next;
+	}
+	/* no entry found */
+	rc = -EINVAL;
+	goto out;
+
+      found:
+
+	/* make snapshot of current debug areas to get it consistent */
+
+	debug_info_snapshot = debug_info_copy(debug_info);
+
+	if(!debug_info_snapshot){
+#ifdef DEBUG
+		printk(KERN_ERR "debug_open: debug_info_copy failed (out of mem)\n");
+#endif
+		rc = -ENOMEM;
+		goto out;
+	}
+
+	if ((file->private_data =
+	     kmalloc(sizeof(file_private_info_t), GFP_ATOMIC)) == 0) {
+#ifdef DEBUG
+		printk(KERN_ERR "debug_open: kmalloc failed\n");
+#endif
+		debug_info_free(debug_info_snapshot);	
+		rc = -ENOMEM;
+		goto out;
+	}
+	p_info = (file_private_info_t *) file->private_data;
+	p_info->offset = 0;
+	p_info->debug_info_snap = debug_info_snapshot;
+	p_info->debug_info_org  = debug_info;
+	p_info->view = debug_info->views[i];
+	p_info->act_area = 0;
+	p_info->act_entry = DEBUG_PROLOG_ENTRY;
+	p_info->act_entry_offset = 0;
+
+	debug_info_get(debug_info);
+
+      out:
+	up(&debug_lock);
+	return rc;
+}
+
+/*
+ * debug_close:
+ * - called for user close()
+ * - deletes  private_data area of the file handle
+ */
+
+static int debug_close(struct inode *inode, struct file *file)
+{
+	file_private_info_t *p_info;
+#ifdef DEBUG
+	printk("debug_close\n");
+#endif
+	p_info = (file_private_info_t *) file->private_data;
+	debug_info_free(p_info->debug_info_snap);
+	debug_info_put(p_info->debug_info_org);
+	kfree(file->private_data);
+	return 0;		/* success */
+}
+
+/*
+ * debug_register:
+ * - creates and initializes debug area for the caller
+ * - returns handle for debug area
+ */
+
+debug_info_t *debug_register
+    (char *name, int page_order, int nr_areas, int buf_size) 
+{
+	debug_info_t *rc = NULL;
+
+	if (!initialized)
+		BUG();
+	down(&debug_lock);
+
+        /* create new debug_info */
+
+	rc = debug_info_create(name, page_order, nr_areas, buf_size);
+	if(!rc) 
+		goto out;
+	debug_register_view(rc, &debug_level_view);
+        debug_register_view(rc, &debug_flush_view);
+#ifdef DEBUG
+	printk(KERN_INFO
+	       "debug: reserved %d areas of %d pages for debugging %s\n",
+	       nr_areas, 1 << page_order, rc->name);
+#endif
+      out:
+        if (rc == NULL){
+		printk(KERN_ERR "debug: debug_register failed for %s\n",name);
+        }
+	up(&debug_lock);
+	return rc;
+}
+
+/*
+ * debug_unregister:
+ * - give back debug area
+ */
+
+void debug_unregister(debug_info_t * id)
+{
+	if (!id)
+		goto out;
+	down(&debug_lock);
+#ifdef DEBUG
+	printk(KERN_INFO "debug: unregistering %s\n", id->name);
+#endif
+	debug_info_put(id);
+	up(&debug_lock);
+
+      out:
+	return;
+}
+
+/*
+ * debug_set_level:
+ * - set actual debug level
+ */
+
+void debug_set_level(debug_info_t* id, int new_level)
+{
+	unsigned long flags;
+	if(!id)
+		return;	
+	spin_lock_irqsave(&id->lock,flags);
+        if(new_level == DEBUG_OFF_LEVEL){
+                id->level = DEBUG_OFF_LEVEL;
+                printk(KERN_INFO "debug: %s: switched off\n",id->name);
+        } else if ((new_level > DEBUG_MAX_LEVEL) || (new_level < 0)) {
+                printk(KERN_INFO
+                        "debug: %s: level %i is out of range (%i - %i)\n",
+                        id->name, new_level, 0, DEBUG_MAX_LEVEL);
+        } else {
+                id->level = new_level;
+#ifdef DEBUG
+                printk(KERN_INFO 
+			"debug: %s: new level %i\n",id->name,id->level);
+#endif
+        }
+	spin_unlock_irqrestore(&id->lock,flags);
+}
+
+
+/*
+ * proceed_active_entry:
+ * - set active entry to next in the ring buffer
+ */
+
+extern inline void proceed_active_entry(debug_info_t * id)
+{
+	if ((id->active_entry[id->active_area] += id->entry_size)
+	    > ((PAGE_SIZE << (id->page_order)) - id->entry_size))
+		id->active_entry[id->active_area] = 0;
+}
+
+/*
+ * proceed_active_area:
+ * - set active area to next in the ring buffer
+ */
+
+extern inline void proceed_active_area(debug_info_t * id)
+{
+	id->active_area++;
+	id->active_area = id->active_area % id->nr_areas;
+}
+
+/*
+ * get_active_entry:
+ */
+
+extern inline debug_entry_t *get_active_entry(debug_info_t * id)
+{
+	return (debug_entry_t *) ((char *) id->areas[id->active_area] +
+				  id->active_entry[id->active_area]);
+}
+
+/*
+ * debug_finish_entry:
+ * - set timestamp, caller address, cpu number etc.
+ */
+
+extern inline void debug_finish_entry(debug_info_t * id, debug_entry_t* active,
+		int level, int exception)
+{
+	STCK(active->id.stck);
+	active->id.fields.cpuid = smp_processor_id();
+	active->caller = __builtin_return_address(0);
+	active->id.fields.exception = exception;
+	active->id.fields.level     = level;
+	proceed_active_entry(id);
+	if(exception)
+		proceed_active_area(id);
+}
+
+static int debug_stoppable=1;
+static int debug_active=1;
+
+#define CTL_S390DBF 5677
+#define CTL_S390DBF_STOPPABLE 5678
+#define CTL_S390DBF_ACTIVE 5679
+
+/*
+ * proc handler for the running debug_active sysctl
+ * always allow read, allow write only if debug_stoppable is set or
+ * if debug_active is already off
+ */
+static int s390dbf_procactive(ctl_table *table, int write, struct file *filp,
+                     void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+	if (!write || debug_stoppable || !debug_active)
+		return proc_dointvec(table, write, filp, buffer, lenp, ppos);
+	else
+		return 0;
+}
+
+
+static struct ctl_table s390dbf_table[] = {
+	{
+		.ctl_name       = CTL_S390DBF_STOPPABLE,
+		.procname       = "debug_stoppable",
+		.data		= &debug_stoppable,
+		.maxlen		= sizeof(int),
+		.mode           = S_IRUGO | S_IWUSR,
+		.proc_handler   = &proc_dointvec,
+		.strategy	= &sysctl_intvec,
+	},
+	 {
+		.ctl_name       = CTL_S390DBF_ACTIVE,
+		.procname       = "debug_active",
+		.data		= &debug_active,
+		.maxlen		= sizeof(int),
+		.mode           = S_IRUGO | S_IWUSR,
+		.proc_handler   = &s390dbf_procactive,
+		.strategy	= &sysctl_intvec,
+	},
+	{ .ctl_name = 0 }
+};
+
+static struct ctl_table s390dbf_dir_table[] = {
+	{
+		.ctl_name       = CTL_S390DBF,
+		.procname       = "s390dbf",
+		.maxlen         = 0,
+		.mode           = S_IRUGO | S_IXUGO,
+		.child          = s390dbf_table,
+	},
+	{ .ctl_name = 0 }
+};
+
+struct ctl_table_header *s390dbf_sysctl_header;
+
+void debug_stop_all(void)
+{
+	if (debug_stoppable)
+		debug_active = 0;
+}
+
+
+/*
+ * debug_event_common:
+ * - write debug entry with given size
+ */
+
+debug_entry_t *debug_event_common(debug_info_t * id, int level, const void *buf,
+			          int len)
+{
+	unsigned long flags;
+	debug_entry_t *active;
+
+	if (!debug_active)
+		return NULL;
+	spin_lock_irqsave(&id->lock, flags);
+	active = get_active_entry(id);
+	memset(DEBUG_DATA(active), 0, id->buf_size);
+	memcpy(DEBUG_DATA(active), buf, min(len, id->buf_size));
+	debug_finish_entry(id, active, level, 0);
+	spin_unlock_irqrestore(&id->lock, flags);
+
+	return active;
+}
+
+/*
+ * debug_exception_common:
+ * - write debug entry with given size and switch to next debug area
+ */
+
+debug_entry_t *debug_exception_common(debug_info_t * id, int level, 
+                                      const void *buf, int len)
+{
+	unsigned long flags;
+	debug_entry_t *active;
+
+	if (!debug_active)
+		return NULL;
+	spin_lock_irqsave(&id->lock, flags);
+	active = get_active_entry(id);
+	memset(DEBUG_DATA(active), 0, id->buf_size);
+	memcpy(DEBUG_DATA(active), buf, min(len, id->buf_size));
+	debug_finish_entry(id, active, level, 1);
+	spin_unlock_irqrestore(&id->lock, flags);
+
+	return active;
+}
+
+/*
+ * counts arguments in format string for sprintf view
+ */
+
+extern inline int debug_count_numargs(char *string)
+{
+	int numargs=0;
+
+	while(*string) {
+		if(*string++=='%')
+			numargs++;
+	}
+	return(numargs);
+}
+
+/*
+ * debug_sprintf_event:
+ */
+
+debug_entry_t *debug_sprintf_event(debug_info_t* id,
+                                   int level,char *string,...)
+{
+	va_list   ap;
+	int numargs,idx;
+	unsigned long flags;
+	debug_sprintf_entry_t *curr_event;
+	debug_entry_t *active;
+
+	if((!id) || (level > id->level))
+		return NULL;
+	if (!debug_active)
+		return NULL;
+	numargs=debug_count_numargs(string);
+
+	spin_lock_irqsave(&id->lock, flags);
+	active = get_active_entry(id);
+	curr_event=(debug_sprintf_entry_t *) DEBUG_DATA(active);
+	va_start(ap,string);
+	curr_event->string=string;
+	for(idx=0;idx<min(numargs,(int)(id->buf_size / sizeof(long))-1);idx++)
+		curr_event->args[idx]=va_arg(ap,long);
+	va_end(ap);
+	debug_finish_entry(id, active, level, 0);
+	spin_unlock_irqrestore(&id->lock, flags);
+
+	return active;
+}
+
+/*
+ * debug_sprintf_exception:
+ */
+
+debug_entry_t *debug_sprintf_exception(debug_info_t* id,
+                                       int level,char *string,...)
+{
+	va_list   ap;
+	int numargs,idx;
+	unsigned long flags;
+	debug_sprintf_entry_t *curr_event;
+	debug_entry_t *active;
+
+	if((!id) || (level > id->level))
+		return NULL;
+	if (!debug_active)
+		return NULL;
+
+	numargs=debug_count_numargs(string);
+
+	spin_lock_irqsave(&id->lock, flags);
+	active = get_active_entry(id);
+	curr_event=(debug_sprintf_entry_t *)DEBUG_DATA(active);
+	va_start(ap,string);
+	curr_event->string=string;
+	for(idx=0;idx<min(numargs,(int)(id->buf_size / sizeof(long))-1);idx++)
+		curr_event->args[idx]=va_arg(ap,long);
+	va_end(ap);
+	debug_finish_entry(id, active, level, 1);
+	spin_unlock_irqrestore(&id->lock, flags);
+
+	return active;
+}
+
+/*
+ * debug_init:
+ * - is called exactly once to initialize the debug feature
+ */
+
+static int __init debug_init(void)
+{
+	int rc = 0;
+
+	s390dbf_sysctl_header = register_sysctl_table(s390dbf_dir_table, 1);
+	down(&debug_lock);
+#ifdef CONFIG_PROC_FS
+	debug_proc_root_entry = proc_mkdir(DEBUG_DIR_ROOT, 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;
+	if (view->prolog_proc || view->format_proc || view->header_proc)
+		mode |= S_IRUSR;
+	if (view->input_proc)
+		mode |= S_IWUSR;
+	pde = create_proc_entry(view->name, mode, id->proc_root_entry);
+	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);
+		remove_proc_entry(pde->name, id->proc_root_entry);
+		rc = -1;
+	}
+	else {
+		id->views[i] = view;
+		pde->proc_fops = &debug_file_ops;
+		id->proc_entries[i] = pde;
+	}
+	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 {
+#ifdef CONFIG_PROC_FS
+		remove_proc_entry(id->proc_entries[i]->name,
+				  id->proc_root_entry);
+#endif
+		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 *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 *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) & PSW_ADDR_INSN;
+	rc += sprintf(out_buf, "%02i %011lu:%06lu %1u %1s %02i %p  ",
+		      area, time_val.tv_sec, time_val.tv_usec, level,
+		      except_str, entry->id.fields.cpuid, (void *) caller);
+	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_t *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;
+}
+
+/*
+ * clean up module
+ */
+void __exit debug_exit(void)
+{
+#ifdef DEBUG
+	printk("debug_cleanup_module: \n");
+#endif
+#ifdef CONFIG_PROC_FS
+	remove_proc_entry(debug_proc_root_entry->name, NULL);
+#endif /* CONFIG_PROC_FS */
+	unregister_sysctl_table(s390dbf_sysctl_header);
+	return;
+}
+
+/*
+ * module definitions
+ */
+core_initcall(debug_init);
+module_exit(debug_exit);
+MODULE_LICENSE("GPL");
+
+EXPORT_SYMBOL(debug_register);
+EXPORT_SYMBOL(debug_unregister); 
+EXPORT_SYMBOL(debug_set_level);
+EXPORT_SYMBOL(debug_stop_all);
+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);