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Diffstat (limited to 'arch/s390/include/asm/debug.h')
| -rw-r--r-- | arch/s390/include/asm/debug.h | 490 |
1 files changed, 490 insertions, 0 deletions
diff --git a/arch/s390/include/asm/debug.h b/arch/s390/include/asm/debug.h new file mode 100644 index 0000000000..ccd4e148b5 --- /dev/null +++ b/arch/s390/include/asm/debug.h @@ -0,0 +1,490 @@ +/* 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; + 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); + +typedef int (debug_format_proc_t) (debug_info_t *id, + struct debug_view *view, char *out_buf, + const char *in_buf); +typedef int (debug_prolog_proc_t) (debug_info_t *id, + struct debug_view *view, + char *out_buf); +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); + +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); + +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 = __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)); \ +__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 */ |