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/* SPDX-License-Identifier: GPL-2.0 *//* *   S/390 debug facility * *    Copyright IBM Corp. 1999, 2020 */#ifndef _ASM_S390_DEBUG_H#define _ASM_S390_DEBUG_H #include <linux/string.h>#include <linux/spinlock.h>#include <linux/kernel.h>#include <linux/time.h>#include <linux/refcount.h>#include <linux/fs.h>#include <linux/init.h> #define DEBUG_MAX_LEVEL		   6  /* debug levels range from 0 to 6 */#define DEBUG_OFF_LEVEL		   -1 /* level where debug is switched off */#define DEBUG_FLUSH_ALL		   -1 /* parameter to flush all areas */#define DEBUG_MAX_VIEWS		   10 /* max number of views in proc fs */#define DEBUG_MAX_NAME_LEN	   64 /* max length for a debugfs file name */#define DEBUG_DEFAULT_LEVEL	   3  /* initial debug level */ #define DEBUG_DIR_ROOT "s390dbf" /* name of debug root directory in proc fs */ #define DEBUG_DATA(entry) (char *)(entry + 1) /* data is stored behind */					      /* the entry information */ #define __DEBUG_FEATURE_VERSION	   3  /* version of debug feature */ struct __debug_entry {	unsigned long clock	: 60;	unsigned long exception	:  1;	unsigned long level	:  3;	void *caller;	unsigned short cpu;} __packed; typedef struct __debug_entry debug_entry_t; struct debug_view; typedef struct debug_info {	struct debug_info *next;	struct debug_info *prev;	refcount_t ref_count;	raw_spinlock_t lock;	int level;	int nr_areas;	int pages_per_area;	int buf_size;	int entry_size;	debug_entry_t ***areas;	int active_area;	int *active_pages;	int *active_entries;	struct dentry *debugfs_root_entry;	struct dentry *debugfs_entries[DEBUG_MAX_VIEWS];	struct debug_view *views[DEBUG_MAX_VIEWS];	char name[DEBUG_MAX_NAME_LEN];	umode_t mode;} debug_info_t; typedef int (debug_header_proc_t) (debug_info_t *id,				   struct debug_view *view,				   int area,				   debug_entry_t *entry,				   char *out_buf, size_t out_buf_size); typedef int (debug_format_proc_t) (debug_info_t *id,				   struct debug_view *view, char *out_buf,				   size_t out_buf_size,				   const char *in_buf);typedef int (debug_prolog_proc_t) (debug_info_t *id,				   struct debug_view *view,				   char *out_buf, size_t out_buf_size);typedef int (debug_input_proc_t) (debug_info_t *id,				  struct debug_view *view,				  struct file *file,				  const char __user *user_buf,				  size_t in_buf_size, loff_t *offset); int debug_dflt_header_fn(debug_info_t *id, struct debug_view *view,			 int area, debug_entry_t *entry,			 char *out_buf, size_t out_buf_size); #define DEBUG_SPRINTF_MAX_ARGS 10int debug_sprintf_format_fn(debug_info_t *id, struct debug_view *view,			    char *out_buf, size_t out_buf_size,			    const char *inbuf);struct debug_view {	char name[DEBUG_MAX_NAME_LEN];	debug_prolog_proc_t *prolog_proc;	debug_header_proc_t *header_proc;	debug_format_proc_t *format_proc;	debug_input_proc_t  *input_proc;	void		    *private_data;}; extern struct debug_view debug_hex_ascii_view;extern struct debug_view debug_sprintf_view; /* do NOT use the _common functions */ debug_entry_t *debug_event_common(debug_info_t *id, int level,				  const void *data, int length); debug_entry_t *debug_exception_common(debug_info_t *id, int level,				      const void *data, int length); /* Debug Feature API: */ debug_info_t *debug_register(const char *name, int pages, int nr_areas,			     int buf_size); debug_info_t *debug_register_mode(const char *name, int pages, int nr_areas,				  int buf_size, umode_t mode, uid_t uid,				  gid_t gid); ssize_t debug_dump(debug_info_t *id, struct debug_view *view,		   char *buf, size_t buf_size, bool reverse); void debug_unregister(debug_info_t *id); void debug_set_level(debug_info_t *id, int new_level); void debug_set_critical(void); void debug_stop_all(void); /** * debug_level_enabled() - Returns true if debug events for the specified *			   level would be logged. Otherwise returns false. * * @id:		handle for debug log * @level:	debug level * * Return: * - %true if level is less or equal to the current debug level. */static inline bool debug_level_enabled(debug_info_t *id, int level){	return level <= id->level;} /** * debug_event() - writes binary debug entry to active debug area *		   (if level <= actual debug level) * * @id:		handle for debug log * @level:	debug level * @data:	pointer to data for debug entry * @length:	length of data in bytes * * Return: * - Address of written debug entry * - %NULL if error */static inline debug_entry_t *debug_event(debug_info_t *id, int level,					 void *data, int length){	if ((!id) || (level > id->level) || (id->pages_per_area == 0))		return NULL;	return debug_event_common(id, level, data, length);} /** * debug_int_event() - writes unsigned integer debug entry to active debug area *		       (if level <= actual debug level) * * @id:		handle for debug log * @level:	debug level * @tag:	integer value for debug entry * * Return: * - Address of written debug entry * - %NULL if error */static inline debug_entry_t *debug_int_event(debug_info_t *id, int level,					     unsigned int tag){	unsigned int t = tag; 	if ((!id) || (level > id->level) || (id->pages_per_area == 0))		return NULL;	return debug_event_common(id, level, &t, sizeof(unsigned int));} /** * debug_long_event() - writes unsigned long debug entry to active debug area *		       (if level <= actual debug level) * * @id:		handle for debug log * @level:	debug level * @tag:	long integer value for debug entry * * Return: * - Address of written debug entry * - %NULL if error */static inline debug_entry_t *debug_long_event(debug_info_t *id, int level,					      unsigned long tag){	unsigned long t = tag; 	if ((!id) || (level > id->level) || (id->pages_per_area == 0))		return NULL;	return debug_event_common(id, level, &t, sizeof(unsigned long));} /** * debug_text_event() - writes string debug entry in ascii format to active *			debug area (if level <= actual debug level) * * @id:		handle for debug log * @level:	debug level * @txt:	string for debug entry * * Return: * - Address of written debug entry * - %NULL if error */static inline debug_entry_t *debug_text_event(debug_info_t *id, int level,					      const char *txt){	if ((!id) || (level > id->level) || (id->pages_per_area == 0))		return NULL;	return debug_event_common(id, level, txt, strlen(txt));} /* * IMPORTANT: Use "%s" in sprintf format strings with care! Only pointers are * stored in the s390dbf. See Documentation/arch/s390/s390dbf.rst for more details! */extern debug_entry_t *__debug_sprintf_event(debug_info_t *id, int level, char *string, ...)	__attribute__ ((format(printf, 3, 4))); /** * debug_sprintf_event() - writes debug entry with format string *			   and varargs (longs) to active debug area *			   (if level $<=$ actual debug level). * * @_id:	handle for debug log * @_level:	debug level * @_fmt:	format string for debug entry * @...:	varargs used as in sprintf() * * Return: * - Address of written debug entry * - %NULL if error * * floats and long long datatypes cannot be used as varargs. */#define debug_sprintf_event(_id, _level, _fmt, ...)			\({									\	debug_entry_t *__ret;						\	debug_info_t *__id = _id;					\	int __level = _level;						\									\	if ((!__id) || (__level > __id->level))				\		__ret = NULL;						\	else								\		__ret = __debug_sprintf_event(__id, __level,		\					      _fmt, ## __VA_ARGS__);	\	__ret;								\}) /** * debug_exception() - writes binary debug entry to active debug area *		       (if level <= actual debug level) *		       and switches to next debug area * * @id:		handle for debug log * @level:	debug level * @data:	pointer to data for debug entry * @length:	length of data in bytes * * Return: * - Address of written debug entry * - %NULL if error */static inline debug_entry_t *debug_exception(debug_info_t *id, int level,					     void *data, int length){	if ((!id) || (level > id->level) || (id->pages_per_area == 0))		return NULL;	return debug_exception_common(id, level, data, length);} /** * debug_int_exception() - writes unsigned int debug entry to active debug area *			   (if level <= actual debug level) *			   and switches to next debug area * * @id:		handle for debug log * @level:	debug level * @tag:	integer value for debug entry * * Return: * - Address of written debug entry * - %NULL if error */static inline debug_entry_t *debug_int_exception(debug_info_t *id, int level,						 unsigned int tag){	unsigned int t = tag; 	if ((!id) || (level > id->level) || (id->pages_per_area == 0))		return NULL;	return debug_exception_common(id, level, &t, sizeof(unsigned int));} /** * debug_long_exception() - writes long debug entry to active debug area *			   (if level <= actual debug level) *			   and switches to next debug area * * @id:		handle for debug log * @level:	debug level * @tag:	long integer value for debug entry * * Return: * - Address of written debug entry * - %NULL if error */static inline debug_entry_t *debug_long_exception (debug_info_t *id, int level,						   unsigned long tag){	unsigned long t = tag; 	if ((!id) || (level > id->level) || (id->pages_per_area == 0))		return NULL;	return debug_exception_common(id, level, &t, sizeof(unsigned long));} /** * debug_text_exception() - writes string debug entry in ascii format to active *			    debug area (if level <= actual debug level) *			    and switches to next debug area * area * * @id:	handle for debug log * @level:	debug level * @txt:	string for debug entry * * Return: * - Address of written debug entry * - %NULL if error */static inline debug_entry_t *debug_text_exception(debug_info_t *id, int level,						  const char *txt){	if ((!id) || (level > id->level) || (id->pages_per_area == 0))		return NULL;	return debug_exception_common(id, level, txt, strlen(txt));} /* * IMPORTANT: Use "%s" in sprintf format strings with care! Only pointers are * stored in the s390dbf. See Documentation/arch/s390/s390dbf.rst for more details! */extern debug_entry_t *__debug_sprintf_exception(debug_info_t *id, int level, char *string, ...)	__attribute__ ((format(printf, 3, 4)));  /** * debug_sprintf_exception() - writes debug entry with format string and *			       varargs (longs) to active debug area *			       (if level <= actual debug level) *			       and switches to next debug area. * * @_id:	handle for debug log * @_level:	debug level * @_fmt:	format string for debug entry * @...:	varargs used as in sprintf() * * Return: * - Address of written debug entry * - %NULL if error * * floats and long long datatypes cannot be used as varargs. */#define debug_sprintf_exception(_id, _level, _fmt, ...)			\({									\	debug_entry_t *__ret;						\	debug_info_t *__id = _id;					\	int __level = _level;						\									\	if ((!__id) || (__level > __id->level))				\		__ret = NULL;						\	else								\		__ret = __debug_sprintf_exception(__id, __level,	\						  _fmt, ## __VA_ARGS__);\	__ret;								\}) int debug_register_view(debug_info_t *id, struct debug_view *view); int debug_unregister_view(debug_info_t *id, struct debug_view *view); #ifndef MODULE /* * Note: Initial page and area numbers must be fixed to allow static * initialization. This enables very early tracing. Changes to these values * must be reflected in __DEFINE_STATIC_AREA. */#define EARLY_PAGES		8#define EARLY_AREAS		1 #define VNAME(var, suffix)	__##var##_##suffix /* * Define static areas for early trace data. During boot debug_register_static() * will replace these with dynamically allocated areas to allow custom page and * area sizes, and dynamic resizing. */#define __DEFINE_STATIC_AREA(var)					\static char VNAME(var, data)[EARLY_PAGES][PAGE_SIZE] __initdata;	\static debug_entry_t *VNAME(var, pages)[EARLY_PAGES] __initdata = {	\	(debug_entry_t *)VNAME(var, data)[0],				\	(debug_entry_t *)VNAME(var, data)[1],				\	(debug_entry_t *)VNAME(var, data)[2],				\	(debug_entry_t *)VNAME(var, data)[3],				\	(debug_entry_t *)VNAME(var, data)[4],				\	(debug_entry_t *)VNAME(var, data)[5],				\	(debug_entry_t *)VNAME(var, data)[6],				\	(debug_entry_t *)VNAME(var, data)[7],				\};									\static debug_entry_t **VNAME(var, areas)[EARLY_AREAS] __initdata = {	\	(debug_entry_t **)VNAME(var, pages),				\};									\static int VNAME(var, active_pages)[EARLY_AREAS] __initdata;		\static int VNAME(var, active_entries)[EARLY_AREAS] __initdata #define __DEBUG_INFO_INIT(var, _name, _buf_size) {			\	.next = NULL,							\	.prev = NULL,							\	.ref_count = REFCOUNT_INIT(1),					\	.lock = __RAW_SPIN_LOCK_UNLOCKED(var.lock),			\	.level = DEBUG_DEFAULT_LEVEL,					\	.nr_areas = EARLY_AREAS,					\	.pages_per_area = EARLY_PAGES,					\	.buf_size = (_buf_size),					\	.entry_size = sizeof(debug_entry_t) + (_buf_size),		\	.areas = VNAME(var, areas),					\	.active_area = 0,						\	.active_pages = VNAME(var, active_pages),			\	.active_entries = VNAME(var, active_entries),			\	.debugfs_root_entry = NULL,					\	.debugfs_entries = { NULL },					\	.views = { NULL },						\	.name = (_name),						\	.mode = 0600,							\} #define __REGISTER_STATIC_DEBUG_INFO(var, name, pages, areas, view)	\static int __init VNAME(var, reg)(void)					\{									\	debug_register_static(&var, (pages), (areas));			\	debug_register_view(&var, (view));				\	return 0;							\}									\arch_initcall(VNAME(var, reg)) /** * DEFINE_STATIC_DEBUG_INFO - Define static debug_info_t * * @var: Name of debug_info_t variable * @name: Name of debug log (e.g. used for debugfs entry) * @pages: Number of pages per area * @nr_areas: Number of debug areas * @buf_size: Size of data area in each debug entry * @view: Pointer to debug view struct * * Define a static debug_info_t for early tracing. The associated debugfs log * is automatically registered with the specified debug view. * * Important: Users of this macro must not call any of the * debug_register/_unregister() functions for this debug_info_t! * * Note: Tracing will start with a fixed number of initial pages and areas. * The debug area will be changed to use the specified numbers during * arch_initcall. */#define DEFINE_STATIC_DEBUG_INFO(var, name, pages, nr_areas, buf_size, view) \__DEFINE_STATIC_AREA(var);						\static debug_info_t __refdata var =					\	__DEBUG_INFO_INIT(var, (name), (buf_size));			\static debug_info_t __used __section(".s390dbf_info") *VNAME(var, info) = &var; \__REGISTER_STATIC_DEBUG_INFO(var, name, pages, nr_areas, view) void debug_register_static(debug_info_t *id, int pages_per_area, int nr_areas); #endif /* MODULE */ #endif /* _ASM_S390_DEBUG_H */