mirror of
git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs.git
synced 2026-10-30 22:03:17 +01:00
Mikhail Zaslonko
28e29992b0
__REGISTER_STATIC_DEBUG_INFO() calls debug_register_view()
unconditionally, even when debug_register_static() has failed. In that
case _debug_register() was never reached and id->debugfs_root_entry is
still NULL, so debugfs_create_file() places the view file in the debugfs
root directory. For sclp_err this leaves a /sys/kernel/debug/hex_ascii
file with nothing to indicate which debug log it belongs to.
debug_register_static() is not exported and the macro is its only
caller, so let it return an error code and skip the view registration
when it fails. No debugfs files are created for such an area then.
Reproduce by booting with s390dbf=sclp_err::100000000. The sclp_err
registration fails, no s390dbf/sclp_err/ directory is created, and a
hex_ascii file appears in the debugfs root instead.
Fixes: d72541f945 ("s390/debug: add early tracing support")
Signed-off-by: Mikhail Zaslonko <[email protected]>
Reviewed-by: Heiko Carstens <[email protected]>
Signed-off-by: Heiko Carstens <[email protected]>
505 lines
15 KiB
C
505 lines
15 KiB
C
/* 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 10
|
|
int 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) \
|
|
{ \
|
|
int rc; \
|
|
\
|
|
rc = debug_register_static(&var, (pages), (areas)); \
|
|
if (rc) \
|
|
return rc; \
|
|
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)
|
|
|
|
int debug_register_static(debug_info_t *id, int pages_per_area, int nr_areas);
|
|
|
|
#endif /* MODULE */
|
|
|
|
#endif /* _ASM_S390_DEBUG_H */
|