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Diffstat (limited to 'arch/s390/kernel/debug.c')
-rw-r--r--arch/s390/kernel/debug.c267
1 files changed, 136 insertions, 131 deletions
diff --git a/arch/s390/kernel/debug.c b/arch/s390/kernel/debug.c
index 1b2f5ce4532..ee8390da6ea 100644
--- a/arch/s390/kernel/debug.c
+++ b/arch/s390/kernel/debug.c
@@ -1,23 +1,25 @@
/*
- * arch/s390/kernel/debug.c
* S/390 debug facility
*
- * Copyright (C) 1999, 2000 IBM Deutschland Entwicklung GmbH,
- * IBM Corporation
+ * Copyright IBM Corp. 1999, 2012
+ *
* Author(s): Michael Holzheu (holzheu@de.ibm.com),
* Holger Smolinski (Holger.Smolinski@de.ibm.com)
*
* Bugreports to: <Linux390@de.ibm.com>
*/
+#define KMSG_COMPONENT "s390dbf"
+#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
+
#include <linux/stddef.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/ctype.h>
+#include <linux/string.h>
#include <linux/sysctl.h>
#include <asm/uaccess.h>
-#include <asm/semaphore.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/fs.h>
@@ -61,8 +63,6 @@ typedef struct
} debug_sprintf_entry_t;
-extern void tod_to_timeval(uint64_t todval, struct timespec *xtime);
-
/* internal function prototyes */
static int debug_init(void);
@@ -72,8 +72,8 @@ 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 pages_per_area,
- int nr_areas, int buf_size);
+static debug_info_t *debug_info_create(const char *name, int pages_per_area,
+ int nr_areas, int buf_size, umode_t mode);
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,
@@ -110,6 +110,7 @@ struct debug_view debug_raw_view = {
NULL,
NULL
};
+EXPORT_SYMBOL(debug_raw_view);
struct debug_view debug_hex_ascii_view = {
"hex_ascii",
@@ -119,6 +120,7 @@ struct debug_view debug_hex_ascii_view = {
NULL,
NULL
};
+EXPORT_SYMBOL(debug_hex_ascii_view);
static struct debug_view debug_level_view = {
"level",
@@ -155,9 +157,10 @@ struct debug_view debug_sprintf_view = {
NULL,
NULL
};
+EXPORT_SYMBOL(debug_sprintf_view);
/* used by dump analysis tools to determine version of debug feature */
-unsigned int debug_feature_version = __DEBUG_FEATURE_VERSION;
+static unsigned int __used debug_feature_version = __DEBUG_FEATURE_VERSION;
/* static globals */
@@ -166,6 +169,7 @@ static debug_info_t *debug_area_last = NULL;
static DEFINE_MUTEX(debug_mutex);
static int initialized;
+static int debug_critical;
static const struct file_operations debug_file_ops = {
.owner = THIS_MODULE,
@@ -173,6 +177,7 @@ static const struct file_operations debug_file_ops = {
.write = debug_input,
.open = debug_open,
.release = debug_close,
+ .llseek = no_llseek,
};
static struct dentry *debug_debugfs_root_entry;
@@ -235,8 +240,8 @@ fail_malloc_areas:
*/
static debug_info_t*
-debug_info_alloc(char *name, int pages_per_area, int nr_areas, int buf_size,
- int level, int mode)
+debug_info_alloc(const char *name, int pages_per_area, int nr_areas,
+ int buf_size, int level, int mode)
{
debug_info_t* rc;
@@ -327,7 +332,8 @@ debug_info_free(debug_info_t* db_info){
*/
static debug_info_t*
-debug_info_create(char *name, int pages_per_area, int nr_areas, int buf_size)
+debug_info_create(const char *name, int pages_per_area, int nr_areas,
+ int buf_size, umode_t mode)
{
debug_info_t* rc;
@@ -336,6 +342,8 @@ debug_info_create(char *name, int pages_per_area, int nr_areas, int buf_size)
if(!rc)
goto out;
+ rc->mode = mode & ~S_IFMT;
+
/* create root directory */
rc->debugfs_root_entry = debugfs_create_dir(rc->name,
debug_debugfs_root_entry);
@@ -386,7 +394,7 @@ debug_info_copy(debug_info_t* in, int mode)
debug_info_free(rc);
} while (1);
- if(!rc || (mode == NO_AREAS))
+ if (mode == NO_AREAS)
goto out;
for(i = 0; i < in->nr_areas; i++){
@@ -598,12 +606,12 @@ debug_input(struct file *file, const char __user *user_buf, size_t length,
static int
debug_open(struct inode *inode, struct file *file)
{
- int i = 0, rc = 0;
+ int i, rc = 0;
file_private_info_t *p_info;
debug_info_t *debug_info, *debug_info_snapshot;
mutex_lock(&debug_mutex);
- debug_info = file->f_path.dentry->d_inode->i_private;
+ debug_info = file_inode(file)->i_private;
/* find debug view */
for (i = 0; i < DEBUG_MAX_VIEWS; i++) {
if (!debug_info->views[i])
@@ -637,8 +645,7 @@ found:
p_info = kmalloc(sizeof(file_private_info_t),
GFP_KERNEL);
if(!p_info){
- if(debug_info_snapshot)
- debug_info_free(debug_info_snapshot);
+ debug_info_free(debug_info_snapshot);
rc = -ENOMEM;
goto out;
}
@@ -652,6 +659,7 @@ found:
p_info->act_entry_offset = 0;
file->private_data = p_info;
debug_info_get(debug_info);
+ nonseekable_open(inode, file);
out:
mutex_unlock(&debug_mutex);
return rc;
@@ -676,23 +684,29 @@ debug_close(struct inode *inode, struct file *file)
}
/*
- * debug_register:
- * - creates and initializes debug area for the caller
- * - returns handle for debug area
+ * debug_register_mode:
+ * - Creates and initializes debug area for the caller
+ * The mode parameter allows to specify access rights for the s390dbf files
+ * - Returns handle for debug area
*/
-debug_info_t*
-debug_register (char *name, int pages_per_area, int nr_areas, int buf_size)
+debug_info_t *debug_register_mode(const char *name, int pages_per_area,
+ int nr_areas, int buf_size, umode_t mode,
+ uid_t uid, gid_t gid)
{
debug_info_t *rc = NULL;
- if (!initialized)
- BUG();
+ /* Since debugfs currently does not support uid/gid other than root, */
+ /* we do not allow gid/uid != 0 until we get support for that. */
+ if ((uid != 0) || (gid != 0))
+ pr_warning("Root becomes the owner of all s390dbf files "
+ "in sysfs\n");
+ BUG_ON(!initialized);
mutex_lock(&debug_mutex);
/* create new debug_info */
- rc = debug_info_create(name, pages_per_area, nr_areas, buf_size);
+ rc = debug_info_create(name, pages_per_area, nr_areas, buf_size, mode);
if(!rc)
goto out;
debug_register_view(rc, &debug_level_view);
@@ -700,11 +714,26 @@ debug_register (char *name, int pages_per_area, int nr_areas, int buf_size)
debug_register_view(rc, &debug_pages_view);
out:
if (!rc){
- printk(KERN_ERR "debug: debug_register failed for %s\n",name);
+ pr_err("Registering debug feature %s failed\n", name);
}
mutex_unlock(&debug_mutex);
return rc;
}
+EXPORT_SYMBOL(debug_register_mode);
+
+/*
+ * debug_register:
+ * - creates and initializes debug area for the caller
+ * - returns handle for debug area
+ */
+
+debug_info_t *debug_register(const char *name, int pages_per_area,
+ int nr_areas, int buf_size)
+{
+ return debug_register_mode(name, pages_per_area, nr_areas, buf_size,
+ S_IRUSR | S_IWUSR, 0, 0);
+}
+EXPORT_SYMBOL(debug_register);
/*
* debug_unregister:
@@ -723,6 +752,7 @@ debug_unregister(debug_info_t * id)
out:
return;
}
+EXPORT_SYMBOL(debug_unregister);
/*
* debug_set_size:
@@ -740,8 +770,8 @@ debug_set_size(debug_info_t* id, int nr_areas, int pages_per_area)
if(pages_per_area > 0){
new_areas = debug_areas_alloc(pages_per_area, nr_areas);
if(!new_areas) {
- printk(KERN_WARNING "debug: could not allocate memory "\
- "for pagenumber: %i\n",pages_per_area);
+ pr_info("Allocating memory for %i pages failed\n",
+ pages_per_area);
rc = -ENOMEM;
goto out;
}
@@ -757,8 +787,7 @@ debug_set_size(debug_info_t* id, int nr_areas, int pages_per_area)
memset(id->active_entries,0,sizeof(int)*id->nr_areas);
memset(id->active_pages, 0, sizeof(int)*id->nr_areas);
spin_unlock_irqrestore(&id->lock,flags);
- printk(KERN_INFO "debug: %s: set new size (%i pages)\n"\
- ,id->name, pages_per_area);
+ pr_info("%s: set new size (%i pages)\n" ,id->name, pages_per_area);
out:
return rc;
}
@@ -777,17 +806,16 @@ debug_set_level(debug_info_t* id, int new_level)
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);
+ pr_info("%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",
+ pr_info("%s: level %i is out of range (%i - %i)\n",
id->name, new_level, 0, DEBUG_MAX_LEVEL);
} else {
id->level = new_level;
}
spin_unlock_irqrestore(&id->lock,flags);
}
-
+EXPORT_SYMBOL(debug_set_level);
/*
* proceed_active_entry:
@@ -839,7 +867,7 @@ static inline void
debug_finish_entry(debug_info_t * id, debug_entry_t* active, int level,
int exception)
{
- active->id.stck = get_clock();
+ active->id.stck = get_tod_clock_fast();
active->id.fields.cpuid = smp_processor_id();
active->caller = __builtin_return_address(0);
active->id.fields.exception = exception;
@@ -861,11 +889,11 @@ static int debug_active=1;
* if debug_active is already off
*/
static int
-s390dbf_procactive(ctl_table *table, int write, struct file *filp,
+s390dbf_procactive(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
if (!write || debug_stoppable || !debug_active)
- return proc_dointvec(table, write, filp, buffer, lenp, ppos);
+ return proc_dointvec(table, write, buffer, lenp, ppos);
else
return 0;
}
@@ -873,35 +901,30 @@ s390dbf_procactive(ctl_table *table, int write, struct file *filp,
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,
+ .proc_handler = proc_dointvec,
},
{
- .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,
+ .proc_handler = s390dbf_procactive,
},
- { .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 }
+ { }
};
static struct ctl_table_header *s390dbf_sysctl_header;
@@ -912,7 +935,12 @@ debug_stop_all(void)
if (debug_stoppable)
debug_active = 0;
}
+EXPORT_SYMBOL(debug_stop_all);
+void debug_set_critical(void)
+{
+ debug_critical = 1;
+}
/*
* debug_event_common:
@@ -927,7 +955,11 @@ debug_event_common(debug_info_t * id, int level, const void *buf, int len)
if (!debug_active || !id->areas)
return NULL;
- spin_lock_irqsave(&id->lock, flags);
+ if (debug_critical) {
+ if (!spin_trylock_irqsave(&id->lock, flags))
+ return NULL;
+ } else
+ 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));
@@ -936,6 +968,7 @@ debug_event_common(debug_info_t * id, int level, const void *buf, int len)
return active;
}
+EXPORT_SYMBOL(debug_event_common);
/*
* debug_exception_common:
@@ -950,7 +983,11 @@ debug_entry_t
if (!debug_active || !id->areas)
return NULL;
- spin_lock_irqsave(&id->lock, flags);
+ if (debug_critical) {
+ if (!spin_trylock_irqsave(&id->lock, flags))
+ return NULL;
+ } else
+ 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));
@@ -959,6 +996,7 @@ debug_entry_t
return active;
}
+EXPORT_SYMBOL(debug_exception_common);
/*
* counts arguments in format string for sprintf view
@@ -995,7 +1033,11 @@ debug_sprintf_event(debug_info_t* id, int level,char *string,...)
return NULL;
numargs=debug_count_numargs(string);
- spin_lock_irqsave(&id->lock, flags);
+ if (debug_critical) {
+ if (!spin_trylock_irqsave(&id->lock, flags))
+ return NULL;
+ } else
+ spin_lock_irqsave(&id->lock, flags);
active = get_active_entry(id);
curr_event=(debug_sprintf_entry_t *) DEBUG_DATA(active);
va_start(ap,string);
@@ -1008,6 +1050,7 @@ debug_sprintf_event(debug_info_t* id, int level,char *string,...)
return active;
}
+EXPORT_SYMBOL(debug_sprintf_event);
/*
* debug_sprintf_exception:
@@ -1029,7 +1072,11 @@ debug_sprintf_exception(debug_info_t* id, int level,char *string,...)
numargs=debug_count_numargs(string);
- spin_lock_irqsave(&id->lock, flags);
+ if (debug_critical) {
+ if (!spin_trylock_irqsave(&id->lock, flags))
+ return NULL;
+ } else
+ spin_lock_irqsave(&id->lock, flags);
active = get_active_entry(id);
curr_event=(debug_sprintf_entry_t *)DEBUG_DATA(active);
va_start(ap,string);
@@ -1042,26 +1089,7 @@ debug_sprintf_exception(debug_info_t* id, int level,char *string,...)
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);
- mutex_lock(&debug_mutex);
- debug_debugfs_root_entry = debugfs_create_dir(DEBUG_DIR_ROOT,NULL);
- printk(KERN_INFO "debug: Initialization complete\n");
- initialized = 1;
- mutex_unlock(&debug_mutex);
-
- return rc;
-}
+EXPORT_SYMBOL(debug_sprintf_exception);
/*
* debug_register_view:
@@ -1073,20 +1101,21 @@ debug_register_view(debug_info_t * id, struct debug_view *view)
int rc = 0;
int i;
unsigned long flags;
- mode_t mode = S_IFREG;
+ umode_t mode;
struct dentry *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;
+ mode = (id->mode | S_IFREG) & ~S_IXUGO;
+ if (!(view->prolog_proc || view->format_proc || view->header_proc))
+ mode &= ~(S_IRUSR | S_IRGRP | S_IROTH);
+ if (!view->input_proc)
+ mode &= ~(S_IWUSR | S_IWGRP | S_IWOTH);
pde = debugfs_create_file(view->name, mode, id->debugfs_root_entry,
id , &debug_file_ops);
if (!pde){
- printk(KERN_WARNING "debug: debugfs_create_file() failed!"\
- " Cannot register view %s/%s\n", id->name,view->name);
+ pr_err("Registering view %s/%s failed due to out of "
+ "memory\n", id->name,view->name);
rc = -1;
goto out;
}
@@ -1096,20 +1125,20 @@ debug_register_view(debug_info_t * id, struct debug_view *view)
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);
- debugfs_remove(pde);
+ pr_err("Registering view %s/%s would exceed the maximum "
+ "number of views %i\n", id->name, view->name, i);
rc = -1;
} else {
id->views[i] = view;
id->debugfs_entries[i] = pde;
}
spin_unlock_irqrestore(&id->lock, flags);
+ if (rc)
+ debugfs_remove(pde);
out:
return rc;
}
+EXPORT_SYMBOL(debug_register_view);
/*
* debug_unregister_view:
@@ -1118,9 +1147,9 @@ out:
int
debug_unregister_view(debug_info_t * id, struct debug_view *view)
{
- int rc = 0;
- int i;
+ struct dentry *dentry = NULL;
unsigned long flags;
+ int i, rc = 0;
if (!id)
goto out;
@@ -1132,14 +1161,16 @@ debug_unregister_view(debug_info_t * id, struct debug_view *view)
if (i == DEBUG_MAX_VIEWS)
rc = -1;
else {
- debugfs_remove(id->debugfs_entries[i]);
+ dentry = id->debugfs_entries[i];
id->views[i] = NULL;
- rc = 0;
+ id->debugfs_entries[i] = NULL;
}
spin_unlock_irqrestore(&id->lock, flags);
+ debugfs_remove(dentry);
out:
return rc;
}
+EXPORT_SYMBOL(debug_unregister_view);
static inline char *
debug_get_user_string(const char __user *user_buf, size_t user_len)
@@ -1166,10 +1197,9 @@ debug_get_uint(char *buf)
{
int rc;
- for(; isspace(*buf); buf++);
+ buf = skip_spaces(buf);
rc = simple_strtoul(buf, &buf, 10);
if(*buf){
- printk("debug: no integer specified!\n");
rc = -EINVAL;
}
return rc;
@@ -1281,7 +1311,8 @@ debug_input_level_fn(debug_info_t * id, struct debug_view *view,
new_level = debug_get_uint(str);
}
if(new_level < 0) {
- printk(KERN_INFO "debug: level `%s` is not valid\n", str);
+ pr_warning("%s is not a valid level for a debug "
+ "feature\n", str);
rc = -EINVAL;
} else {
debug_set_level(id, new_level);
@@ -1316,19 +1347,12 @@ static void debug_flush(debug_info_t* id, int area)
memset(id->areas[i][j], 0, PAGE_SIZE);
}
}
- printk(KERN_INFO "debug: %s: all areas flushed\n",id->name);
} else if(area >= 0 && area < id->nr_areas) {
id->active_entries[area] = 0;
id->active_pages[area] = 0;
for(i = 0; i < id->pages_per_area; i++) {
memset(id->areas[area][i],0,PAGE_SIZE);
}
- 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);
}
@@ -1365,7 +1389,8 @@ debug_input_flush_fn(debug_info_t * id, struct debug_view *view,
goto out;
}
- printk(KERN_INFO "debug: area `%c` is not valid\n", input_buf[0]);
+ pr_info("Flushing debug data failed because %c is not a valid "
+ "area\n", input_buf[0]);
out:
*offset += user_len;
@@ -1419,10 +1444,10 @@ debug_hex_ascii_format_fn(debug_info_t * id, struct debug_view *view,
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
+ if (isascii(c) && isprint(c))
rc += sprintf(out_buf + rc, "%c", c);
+ else
+ rc += sprintf(out_buf + rc, ".");
}
rc += sprintf(out_buf + rc, "\n");
return rc;
@@ -1437,17 +1462,13 @@ debug_dflt_header_fn(debug_info_t * id, struct debug_view *view,
int area, debug_entry_t * entry, char *out_buf)
{
struct timespec time_spec;
- 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_spec);
+ stck_to_timespec(entry->id.stck, &time_spec);
if (entry->id.fields.exception)
except_str = "*";
@@ -1459,6 +1480,7 @@ debug_dflt_header_fn(debug_info_t * id, struct debug_view *view,
except_str, entry->id.fields.cpuid, (void *) caller);
return rc;
}
+EXPORT_SYMBOL(debug_dflt_header_fn);
/*
* prints debug data sprintf-formated:
@@ -1507,33 +1529,16 @@ out:
}
/*
- * clean up module
+ * debug_init:
+ * - is called exactly once to initialize the debug feature
*/
-static void __exit debug_exit(void)
+static int __init debug_init(void)
{
- debugfs_remove(debug_debugfs_root_entry);
- unregister_sysctl_table(s390dbf_sysctl_header);
- return;
+ s390dbf_sysctl_header = register_sysctl_table(s390dbf_dir_table);
+ mutex_lock(&debug_mutex);
+ debug_debugfs_root_entry = debugfs_create_dir(DEBUG_DIR_ROOT, NULL);
+ initialized = 1;
+ mutex_unlock(&debug_mutex);
+ return 0;
}
-
-/*
- * module definitions
- */
postcore_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);
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-10 03:26:01 +0000