[linux-block.git] / lib / fault-inject.c

// SPDX-License-Identifier: GPL-2.0-only
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/random.h>
#include <linux/sched.h>
#include <linux/stat.h>
#include <linux/types.h>
#include <linux/fs.h>
#include <linux/export.h>
#include <linux/interrupt.h>
#include <linux/stacktrace.h>
#include <linux/fault-inject.h>

/*
 * setup_fault_attr() is a helper function for various __setup handlers, so it
 * returns 0 on error, because that is what __setup handlers do.
 */
int setup_fault_attr(struct fault_attr *attr, char *str)
{
	unsigned long probability;
	unsigned long interval;
	int times;
	int space;

	/* "<interval>,<probability>,<space>,<times>" */
	if (sscanf(str, "%lu,%lu,%d,%d",
			&interval, &probability, &space, &times) < 4) {
		printk(KERN_WARNING
			"FAULT_INJECTION: failed to parse arguments\n");
		return 0;
	}

	attr->probability = probability;
	attr->interval = interval;
	atomic_set(&attr->times, times);
	atomic_set(&attr->space, space);

	return 1;
}
EXPORT_SYMBOL_GPL(setup_fault_attr);

static void fail_dump(struct fault_attr *attr)
{
	if (attr->verbose > 0 && __ratelimit(&attr->ratelimit_state)) {
		printk(KERN_NOTICE "FAULT_INJECTION: forcing a failure.\n"
		       "name %pd, interval %lu, probability %lu, "
		       "space %d, times %d\n", attr->dname,
		       attr->interval, attr->probability,
		       atomic_read(&attr->space),
		       atomic_read(&attr->times));
		if (attr->verbose > 1)
			dump_stack();
	}
}

#define atomic_dec_not_zero(v)		atomic_add_unless((v), -1, 0)

static bool fail_task(struct fault_attr *attr, struct task_struct *task)
{
	return in_task() && task->make_it_fail;
}

#define MAX_STACK_TRACE_DEPTH 32

#ifdef CONFIG_FAULT_INJECTION_STACKTRACE_FILTER

static bool fail_stacktrace(struct fault_attr *attr)
{
	int depth = attr->stacktrace_depth;
	unsigned long entries[MAX_STACK_TRACE_DEPTH];
	int n, nr_entries;
	bool found = (attr->require_start == 0 && attr->require_end == ULONG_MAX);

	if (depth == 0 || (found && !attr->reject_start && !attr->reject_end))
		return found;

	nr_entries = stack_trace_save(entries, depth, 1);
	for (n = 0; n < nr_entries; n++) {
		if (attr->reject_start <= entries[n] &&
			       entries[n] < attr->reject_end)
			return false;
		if (attr->require_start <= entries[n] &&
			       entries[n] < attr->require_end)
			found = true;
	}
	return found;
}

#else

static inline bool fail_stacktrace(struct fault_attr *attr)
{
	return true;
}

#endif /* CONFIG_FAULT_INJECTION_STACKTRACE_FILTER */

/*
 * This code is stolen from failmalloc-1.0
 * http://www.nongnu.org/failmalloc/
 */

bool should_fail_ex(struct fault_attr *attr, ssize_t size, int flags)
{
	bool stack_checked = false;

	if (in_task()) {
		unsigned int fail_nth = READ_ONCE(current->fail_nth);

		if (fail_nth) {
			if (!fail_stacktrace(attr))
				return false;

			stack_checked = true;
			fail_nth--;
			WRITE_ONCE(current->fail_nth, fail_nth);
			if (!fail_nth)
				goto fail;

			return false;
		}
	}

	/* No need to check any other properties if the probability is 0 */
	if (attr->probability == 0)
		return false;

	if (attr->task_filter && !fail_task(attr, current))
		return false;

	if (atomic_read(&attr->times) == 0)
		return false;

	if (!stack_checked && !fail_stacktrace(attr))
		return false;

	if (atomic_read(&attr->space) > size) {
		atomic_sub(size, &attr->space);
		return false;
	}

	if (attr->interval > 1) {
		attr->count++;
		if (attr->count % attr->interval)
			return false;
	}

	if (attr->probability <= get_random_u32_below(100))
		return false;

fail:
	if (!(flags & FAULT_NOWARN))
		fail_dump(attr);

	if (atomic_read(&attr->times) != -1)
		atomic_dec_not_zero(&attr->times);

	return true;
}

bool should_fail(struct fault_attr *attr, ssize_t size)
{
	return should_fail_ex(attr, size, 0);
}
EXPORT_SYMBOL_GPL(should_fail);

#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS

static int debugfs_ul_set(void *data, u64 val)
{
	*(unsigned long *)data = val;
	return 0;
}

static int debugfs_ul_get(void *data, u64 *val)
{
	*val = *(unsigned long *)data;
	return 0;
}

DEFINE_SIMPLE_ATTRIBUTE(fops_ul, debugfs_ul_get, debugfs_ul_set, "%llu\n");

static void debugfs_create_ul(const char *name, umode_t mode,
			      struct dentry *parent, unsigned long *value)
{
	debugfs_create_file(name, mode, parent, value, &fops_ul);
}

#ifdef CONFIG_FAULT_INJECTION_STACKTRACE_FILTER

static int debugfs_stacktrace_depth_set(void *data, u64 val)
{
	*(unsigned long *)data =
		min_t(unsigned long, val, MAX_STACK_TRACE_DEPTH);

	return 0;
}

DEFINE_SIMPLE_ATTRIBUTE(fops_stacktrace_depth, debugfs_ul_get,
			debugfs_stacktrace_depth_set, "%llu\n");

static void debugfs_create_stacktrace_depth(const char *name, umode_t mode,
					    struct dentry *parent,
					    unsigned long *value)
{
	debugfs_create_file(name, mode, parent, value, &fops_stacktrace_depth);
}

#endif /* CONFIG_FAULT_INJECTION_STACKTRACE_FILTER */

struct dentry *fault_create_debugfs_attr(const char *name,
			struct dentry *parent, struct fault_attr *attr)
{
	umode_t mode = S_IFREG | S_IRUSR | S_IWUSR;
	struct dentry *dir;

	dir = debugfs_create_dir(name, parent);
	if (IS_ERR(dir))
		return dir;

	debugfs_create_ul("probability", mode, dir, &attr->probability);
	debugfs_create_ul("interval", mode, dir, &attr->interval);
	debugfs_create_atomic_t("times", mode, dir, &attr->times);
	debugfs_create_atomic_t("space", mode, dir, &attr->space);
	debugfs_create_ul("verbose", mode, dir, &attr->verbose);
	debugfs_create_u32("verbose_ratelimit_interval_ms", mode, dir,
			   &attr->ratelimit_state.interval);
	debugfs_create_u32("verbose_ratelimit_burst", mode, dir,
			   &attr->ratelimit_state.burst);
	debugfs_create_bool("task-filter", mode, dir, &attr->task_filter);

#ifdef CONFIG_FAULT_INJECTION_STACKTRACE_FILTER
	debugfs_create_stacktrace_depth("stacktrace-depth", mode, dir,
					&attr->stacktrace_depth);
	debugfs_create_xul("require-start", mode, dir, &attr->require_start);
	debugfs_create_xul("require-end", mode, dir, &attr->require_end);
	debugfs_create_xul("reject-start", mode, dir, &attr->reject_start);
	debugfs_create_xul("reject-end", mode, dir, &attr->reject_end);
#endif /* CONFIG_FAULT_INJECTION_STACKTRACE_FILTER */

	attr->dname = dget(dir);
	return dir;
}
EXPORT_SYMBOL_GPL(fault_create_debugfs_attr);

#endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */

#ifdef CONFIG_FAULT_INJECTION_CONFIGFS

/* These configfs attribute utilities are copied from drivers/block/null_blk/main.c */

static ssize_t fault_uint_attr_show(unsigned int val, char *page)
{
	return snprintf(page, PAGE_SIZE, "%u\n", val);
}

static ssize_t fault_ulong_attr_show(unsigned long val, char *page)
{
	return snprintf(page, PAGE_SIZE, "%lu\n", val);
}

static ssize_t fault_bool_attr_show(bool val, char *page)
{
	return snprintf(page, PAGE_SIZE, "%u\n", val);
}

static ssize_t fault_atomic_t_attr_show(atomic_t val, char *page)
{
	return snprintf(page, PAGE_SIZE, "%d\n", atomic_read(&val));
}

static ssize_t fault_uint_attr_store(unsigned int *val, const char *page, size_t count)
{
	unsigned int tmp;
	int result;

	result = kstrtouint(page, 0, &tmp);
	if (result < 0)
		return result;

	*val = tmp;
	return count;
}

static ssize_t fault_ulong_attr_store(unsigned long *val, const char *page, size_t count)
{
	int result;
	unsigned long tmp;

	result = kstrtoul(page, 0, &tmp);
	if (result < 0)
		return result;

	*val = tmp;
	return count;
}

static ssize_t fault_bool_attr_store(bool *val, const char *page, size_t count)
{
	bool tmp;
	int result;

	result = kstrtobool(page, &tmp);
	if (result < 0)
		return result;

	*val = tmp;
	return count;
}

static ssize_t fault_atomic_t_attr_store(atomic_t *val, const char *page, size_t count)
{
	int tmp;
	int result;

	result = kstrtoint(page, 0, &tmp);
	if (result < 0)
		return result;

	atomic_set(val, tmp);
	return count;
}

#define CONFIGFS_ATTR_NAMED(_pfx, _name, _attr_name)	\
static struct configfs_attribute _pfx##attr_##_name = {	\
	.ca_name	= _attr_name,			\
	.ca_mode	= 0644,				\
	.ca_owner	= THIS_MODULE,			\
	.show		= _pfx##_name##_show,		\
	.store		= _pfx##_name##_store,		\
}

static struct fault_config *to_fault_config(struct config_item *item)
{
	return container_of(to_config_group(item), struct fault_config, group);
}

#define FAULT_CONFIGFS_ATTR_NAMED(NAME, ATTR_NAME, MEMBER, TYPE)				\
static ssize_t fault_##NAME##_show(struct config_item *item, char *page)			\
{												\
	return fault_##TYPE##_attr_show(to_fault_config(item)->attr.MEMBER, page);		\
}												\
static ssize_t fault_##NAME##_store(struct config_item *item, const char *page, size_t count)	\
{												\
	struct fault_config *config = to_fault_config(item);					\
	return fault_##TYPE##_attr_store(&config->attr.MEMBER, page, count);			\
}												\
CONFIGFS_ATTR_NAMED(fault_, NAME, ATTR_NAME)

#define FAULT_CONFIGFS_ATTR(NAME, TYPE)	\
	FAULT_CONFIGFS_ATTR_NAMED(NAME, __stringify(NAME), NAME, TYPE)

FAULT_CONFIGFS_ATTR(probability, ulong);
FAULT_CONFIGFS_ATTR(interval, ulong);
FAULT_CONFIGFS_ATTR(times, atomic_t);
FAULT_CONFIGFS_ATTR(space, atomic_t);
FAULT_CONFIGFS_ATTR(verbose, ulong);
FAULT_CONFIGFS_ATTR_NAMED(ratelimit_interval, "verbose_ratelimit_interval_ms",
		ratelimit_state.interval, uint);
FAULT_CONFIGFS_ATTR_NAMED(ratelimit_burst, "verbose_ratelimit_burst",
		ratelimit_state.burst, uint);
FAULT_CONFIGFS_ATTR_NAMED(task_filter, "task-filter", task_filter, bool);

#ifdef CONFIG_FAULT_INJECTION_STACKTRACE_FILTER

static ssize_t fault_stacktrace_depth_show(struct config_item *item, char *page)
{
	return fault_ulong_attr_show(to_fault_config(item)->attr.stacktrace_depth, page);
}

static ssize_t fault_stacktrace_depth_store(struct config_item *item, const char *page,
		size_t count)
{
	int result;
	unsigned long tmp;

	result = kstrtoul(page, 0, &tmp);
	if (result < 0)
		return result;

	to_fault_config(item)->attr.stacktrace_depth =
		min_t(unsigned long, tmp, MAX_STACK_TRACE_DEPTH);

	return count;
}

CONFIGFS_ATTR_NAMED(fault_, stacktrace_depth, "stacktrace-depth");

static ssize_t fault_xul_attr_show(unsigned long val, char *page)
{
	return snprintf(page, PAGE_SIZE,
			sizeof(val) == sizeof(u32) ? "0x%08lx\n" : "0x%016lx\n", val);
}

static ssize_t fault_xul_attr_store(unsigned long *val, const char *page, size_t count)
{
	return fault_ulong_attr_store(val, page, count);
}

FAULT_CONFIGFS_ATTR_NAMED(require_start, "require-start", require_start, xul);
FAULT_CONFIGFS_ATTR_NAMED(require_end, "require-end", require_end, xul);
FAULT_CONFIGFS_ATTR_NAMED(reject_start, "reject-start", reject_start, xul);
FAULT_CONFIGFS_ATTR_NAMED(reject_end, "reject-end", reject_end, xul);

#endif /* CONFIG_FAULT_INJECTION_STACKTRACE_FILTER */

static struct configfs_attribute *fault_config_attrs[] = {
	&fault_attr_probability,
	&fault_attr_interval,
	&fault_attr_times,
	&fault_attr_space,
	&fault_attr_verbose,
	&fault_attr_ratelimit_interval,
	&fault_attr_ratelimit_burst,
	&fault_attr_task_filter,
#ifdef CONFIG_FAULT_INJECTION_STACKTRACE_FILTER
	&fault_attr_stacktrace_depth,
	&fault_attr_require_start,
	&fault_attr_require_end,
	&fault_attr_reject_start,
	&fault_attr_reject_end,
#endif /* CONFIG_FAULT_INJECTION_STACKTRACE_FILTER */
	NULL,
};

static const struct config_item_type fault_config_type = {
	.ct_attrs	= fault_config_attrs,
	.ct_owner	= THIS_MODULE,
};

void fault_config_init(struct fault_config *config, const char *name)
{
	config_group_init_type_name(&config->group, name, &fault_config_type);
}
EXPORT_SYMBOL_GPL(fault_config_init);

#endif /* CONFIG_FAULT_INJECTION_CONFIGFS */
Commit	Line	Data
457c8996	1	// SPDX-License-Identifier: GPL-2.0-only
6ff1cb35 AM	2	#include <linux/kernel.h>
	3	#include <linux/init.h>
	4	#include <linux/random.h>
d43c36dc	5	#include <linux/sched.h>
6ff1cb35 AM	6	#include <linux/stat.h>
	7	#include <linux/types.h>
	8	#include <linux/fs.h>
8bc3bcc9	9	#include <linux/export.h>
f4f154fd	10	#include <linux/interrupt.h>
329409ae	11	#include <linux/stacktrace.h>
6ff1cb35 AM	12	#include <linux/fault-inject.h>
	13
	14	/*
	15	* setup_fault_attr() is a helper function for various __setup handlers, so it
	16	* returns 0 on error, because that is what __setup handlers do.
	17	*/
6cba00ea	18	int setup_fault_attr(struct fault_attr attr, char str)
6ff1cb35 AM	19	{
	20	unsigned long probability;
	21	unsigned long interval;
	22	int times;
	23	int space;
	24
	25	/* "<interval>,<probability>,<space>,<times>" */
	26	if (sscanf(str, "%lu,%lu,%d,%d",
	27	&interval, &probability, &space, &times) < 4) {
	28	printk(KERN_WARNING
	29	"FAULT_INJECTION: failed to parse arguments\n");
	30	return 0;
	31	}
	32
	33	attr->probability = probability;
	34	attr->interval = interval;
	35	atomic_set(&attr->times, times);
	36	atomic_set(&attr->space, space);
	37
	38	return 1;
	39	}
6cba00ea	40	EXPORT_SYMBOL_GPL(setup_fault_attr);
6ff1cb35 AM	41
	42	static void fail_dump(struct fault_attr *attr)
	43	{
6adc4a22 DM	44	if (attr->verbose > 0 && __ratelimit(&attr->ratelimit_state)) {
	45	printk(KERN_NOTICE "FAULT_INJECTION: forcing a failure.\n"
	46	"name %pd, interval %lu, probability %lu, "
	47	"space %d, times %d\n", attr->dname,
bb387002	48	attr->interval, attr->probability,
6adc4a22 DM	49	atomic_read(&attr->space),
	50	atomic_read(&attr->times));
	51	if (attr->verbose > 1)
	52	dump_stack();
	53	}
6ff1cb35 AM	54	}
	55
	56	#define atomic_dec_not_zero(v) atomic_add_unless((v), -1, 0)
	57
08b3df2d	58	static bool fail_task(struct fault_attr attr, struct task_struct task)
f4f154fd	59	{
f2ad37da	60	return in_task() && task->make_it_fail;
f4f154fd AM	61	}
f4f154fd AM	62
a124c28e DM	63	#define MAX_STACK_TRACE_DEPTH 32
a124c28e DM	64
1df49008	65	#ifdef CONFIG_FAULT_INJECTION_STACKTRACE_FILTER
329409ae	66
08b3df2d	67	static bool fail_stacktrace(struct fault_attr *attr)
329409ae	68	{
329409ae AM	69	int depth = attr->stacktrace_depth;
329409ae AM	70	unsigned long entries[MAX_STACK_TRACE_DEPTH];
30191250	71	int n, nr_entries;
329409ae AM	72	bool found = (attr->require_start == 0 && attr->require_end == ULONG_MAX);
329409ae AM	73
4acb9e51	74	if (depth == 0 \|\| (found && !attr->reject_start && !attr->reject_end))
329409ae AM	75	return found;
329409ae AM	76
30191250 TG	77	nr_entries = stack_trace_save(entries, depth, 1);
30191250 TG	78	for (n = 0; n < nr_entries; n++) {
329409ae AM	79	if (attr->reject_start <= entries[n] &&
329409ae AM	80	entries[n] < attr->reject_end)
08b3df2d	81	return false;
329409ae AM	82	if (attr->require_start <= entries[n] &&
329409ae AM	83	entries[n] < attr->require_end)
08b3df2d	84	found = true;
329409ae AM	85	}
	86	return found;
	87	}
	88
	89	#else
	90
08b3df2d	91	static inline bool fail_stacktrace(struct fault_attr *attr)
329409ae	92	{
1df49008	93	return true;
329409ae AM	94	}
329409ae AM	95
1df49008	96	#endif /* CONFIG_FAULT_INJECTION_STACKTRACE_FILTER */
329409ae	97
6ff1cb35 AM	98	/*
	99	* This code is stolen from failmalloc-1.0
	100	* http://www.nongnu.org/failmalloc/
	101	*/
	102
ea4452de	103	bool should_fail_ex(struct fault_attr *attr, ssize_t size, int flags)
6ff1cb35	104	{
f9eeef59 WY	105	bool stack_checked = false;
f9eeef59 WY	106
1203c8e6 AM	107	if (in_task()) {
	108	unsigned int fail_nth = READ_ONCE(current->fail_nth);
	109
9eeb52ae	110	if (fail_nth) {
f9eeef59 WY	111	if (!fail_stacktrace(attr))
	112	return false;
	113
	114	stack_checked = true;
9b4fb5ce WD	115	fail_nth--;
	116	WRITE_ONCE(current->fail_nth, fail_nth);
	117	if (!fail_nth)
9eeb52ae	118	goto fail;
1203c8e6	119
9eeb52ae AM	120	return false;
9eeb52ae AM	121	}
e41d5818 DV	122	}
e41d5818 DV	123
f39cdaeb AB	124	/* No need to check any other properties if the probability is 0 */
	125	if (attr->probability == 0)
	126	return false;
	127
f4f154fd	128	if (attr->task_filter && !fail_task(attr, current))
08b3df2d	129	return false;
f4f154fd	130
6ff1cb35	131	if (atomic_read(&attr->times) == 0)
08b3df2d	132	return false;
6ff1cb35	133
f9eeef59 WY	134	if (!stack_checked && !fail_stacktrace(attr))
	135	return false;
	136
6ff1cb35 AM	137	if (atomic_read(&attr->space) > size) {
6ff1cb35 AM	138	atomic_sub(size, &attr->space);
08b3df2d	139	return false;
6ff1cb35 AM	140	}
	141
	142	if (attr->interval > 1) {
	143	attr->count++;
	144	if (attr->count % attr->interval)
08b3df2d	145	return false;
6ff1cb35 AM	146	}
6ff1cb35 AM	147
8032bf12	148	if (attr->probability <= get_random_u32_below(100))
f1729c28	149	return false;
6ff1cb35	150
e41d5818	151	fail:
ea4452de QZ	152	if (!(flags & FAULT_NOWARN))
ea4452de QZ	153	fail_dump(attr);
6ff1cb35 AM	154
	155	if (atomic_read(&attr->times) != -1)
	156	atomic_dec_not_zero(&attr->times);
	157
08b3df2d	158	return true;
6ff1cb35	159	}
ea4452de QZ	160
	161	bool should_fail(struct fault_attr *attr, ssize_t size)
	162	{
	163	return should_fail_ex(attr, size, 0);
	164	}
df87ecbf	165	EXPORT_SYMBOL_GPL(should_fail);
6ff1cb35 AM	166
	167	#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
	168
8b88b099	169	static int debugfs_ul_set(void *data, u64 val)
6ff1cb35 AM	170	{
6ff1cb35 AM	171	(unsigned long )data = val;
8b88b099	172	return 0;
6ff1cb35 AM	173	}
6ff1cb35 AM	174
8b88b099	175	static int debugfs_ul_get(void data, u64 val)
6ff1cb35	176	{
8b88b099 CH	177	val = (unsigned long *)data;
8b88b099 CH	178	return 0;
6ff1cb35 AM	179	}
	180
	181	DEFINE_SIMPLE_ATTRIBUTE(fops_ul, debugfs_ul_get, debugfs_ul_set, "%llu\n");
	182
053cf510 GKH	183	static void debugfs_create_ul(const char *name, umode_t mode,
053cf510 GKH	184	struct dentry parent, unsigned long value)
6ff1cb35	185	{
053cf510	186	debugfs_create_file(name, mode, parent, value, &fops_ul);
6ff1cb35 AM	187	}
6ff1cb35 AM	188
6ddb23c7	189	#ifdef CONFIG_FAULT_INJECTION_STACKTRACE_FILTER
a124c28e	190
8307fc25 AM	191	static int debugfs_stacktrace_depth_set(void *data, u64 val)
	192	{
	193	(unsigned long )data =
	194	min_t(unsigned long, val, MAX_STACK_TRACE_DEPTH);
	195
	196	return 0;
	197	}
	198
	199	DEFINE_SIMPLE_ATTRIBUTE(fops_stacktrace_depth, debugfs_ul_get,
	200	debugfs_stacktrace_depth_set, "%llu\n");
	201
053cf510 GKH	202	static void debugfs_create_stacktrace_depth(const char *name, umode_t mode,
	203	struct dentry *parent,
	204	unsigned long *value)
a124c28e	205	{
053cf510	206	debugfs_create_file(name, mode, parent, value, &fops_stacktrace_depth);
a124c28e	207	}
8307fc25	208
6ddb23c7	209	#endif /* CONFIG_FAULT_INJECTION_STACKTRACE_FILTER */
a124c28e	210
dd48c085 AM	211	struct dentry fault_create_debugfs_attr(const char name,
dd48c085 AM	212	struct dentry parent, struct fault_attr attr)
6ff1cb35	213	{
f4ae40a6	214	umode_t mode = S_IFREG \| S_IRUSR \| S_IWUSR;
6ff1cb35 AM	215	struct dentry *dir;
6ff1cb35 AM	216
dd48c085	217	dir = debugfs_create_dir(name, parent);
053cf510 GKH	218	if (IS_ERR(dir))
	219	return dir;
	220
	221	debugfs_create_ul("probability", mode, dir, &attr->probability);
	222	debugfs_create_ul("interval", mode, dir, &attr->interval);
	223	debugfs_create_atomic_t("times", mode, dir, &attr->times);
	224	debugfs_create_atomic_t("space", mode, dir, &attr->space);
	225	debugfs_create_ul("verbose", mode, dir, &attr->verbose);
	226	debugfs_create_u32("verbose_ratelimit_interval_ms", mode, dir,
	227	&attr->ratelimit_state.interval);
	228	debugfs_create_u32("verbose_ratelimit_burst", mode, dir,
	229	&attr->ratelimit_state.burst);
	230	debugfs_create_bool("task-filter", mode, dir, &attr->task_filter);
1df49008 AM	231
1df49008 AM	232	#ifdef CONFIG_FAULT_INJECTION_STACKTRACE_FILTER
053cf510 GKH	233	debugfs_create_stacktrace_depth("stacktrace-depth", mode, dir,
053cf510 GKH	234	&attr->stacktrace_depth);
01999074 WY	235	debugfs_create_xul("require-start", mode, dir, &attr->require_start);
	236	debugfs_create_xul("require-end", mode, dir, &attr->require_end);
	237	debugfs_create_xul("reject-start", mode, dir, &attr->reject_start);
	238	debugfs_create_xul("reject-end", mode, dir, &attr->reject_end);
1df49008 AM	239	#endif /* CONFIG_FAULT_INJECTION_STACKTRACE_FILTER */
1df49008 AM	240
6adc4a22	241	attr->dname = dget(dir);
dd48c085	242	return dir;
6ff1cb35	243	}
df87ecbf	244	EXPORT_SYMBOL_GPL(fault_create_debugfs_attr);
6ff1cb35 AM	245
6ff1cb35 AM	246	#endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */
4668c7a2 AM	247
	248	#ifdef CONFIG_FAULT_INJECTION_CONFIGFS
	249
	250	/* These configfs attribute utilities are copied from drivers/block/null_blk/main.c */
	251
	252	static ssize_t fault_uint_attr_show(unsigned int val, char *page)
	253	{
	254	return snprintf(page, PAGE_SIZE, "%u\n", val);
	255	}
	256
	257	static ssize_t fault_ulong_attr_show(unsigned long val, char *page)
	258	{
	259	return snprintf(page, PAGE_SIZE, "%lu\n", val);
	260	}
	261
	262	static ssize_t fault_bool_attr_show(bool val, char *page)
	263	{
	264	return snprintf(page, PAGE_SIZE, "%u\n", val);
	265	}
	266
	267	static ssize_t fault_atomic_t_attr_show(atomic_t val, char *page)
	268	{
	269	return snprintf(page, PAGE_SIZE, "%d\n", atomic_read(&val));
	270	}
	271
	272	static ssize_t fault_uint_attr_store(unsigned int val, const char page, size_t count)
	273	{
	274	unsigned int tmp;
	275	int result;
	276
	277	result = kstrtouint(page, 0, &tmp);
	278	if (result < 0)
	279	return result;
	280
	281	*val = tmp;
	282	return count;
	283	}
	284
	285	static ssize_t fault_ulong_attr_store(unsigned long val, const char page, size_t count)
	286	{
	287	int result;
	288	unsigned long tmp;
	289
	290	result = kstrtoul(page, 0, &tmp);
	291	if (result < 0)
	292	return result;
	293
	294	*val = tmp;
	295	return count;
	296	}
	297
	298	static ssize_t fault_bool_attr_store(bool val, const char page, size_t count)
	299	{
	300	bool tmp;
	301	int result;
	302
	303	result = kstrtobool(page, &tmp);
	304	if (result < 0)
	305	return result;
	306
	307	*val = tmp;
	308	return count;
	309	}
	310
311	static ssize_t fault_atomic_t_attr_store(atomic_t val, const char page, size_t count)
312	{
313	int tmp;
314	int result;
315
316	result = kstrtoint(page, 0, &tmp);
317	if (result < 0)
318	return result;
319
320	atomic_set(val, tmp);
321	return count;
322	}
323
324	#define CONFIGFS_ATTR_NAMED(_pfx, _name, _attr_name) \
325	static struct configfs_attribute _pfx##attr_##_name = { \
326	.ca_name = _attr_name, \
327	.ca_mode = 0644, \
328	.ca_owner = THIS_MODULE, \
329	.show = _pfx##_name##_show, \
330	.store = _pfx##_name##_store, \
331	}
332
333	static struct fault_config to_fault_config(struct config_item item)
334	{
335	return container_of(to_config_group(item), struct fault_config, group);
336	}
337
338	#define FAULT_CONFIGFS_ATTR_NAMED(NAME, ATTR_NAME, MEMBER, TYPE) \
339	static ssize_t fault_##NAME##_show(struct config_item item, char page) \
340	{ \
341	return fault_##TYPE##_attr_show(to_fault_config(item)->attr.MEMBER, page); \
342	} \
343	static ssize_t fault_##NAME##_store(struct config_item item, const char page, size_t count) \
344	{ \
345	struct fault_config *config = to_fault_config(item); \
346	return fault_##TYPE##_attr_store(&config->attr.MEMBER, page, count); \
347	} \
348	CONFIGFS_ATTR_NAMED(fault_, NAME, ATTR_NAME)
349
350	#define FAULT_CONFIGFS_ATTR(NAME, TYPE) \
351	FAULT_CONFIGFS_ATTR_NAMED(NAME, __stringify(NAME), NAME, TYPE)
352
353	FAULT_CONFIGFS_ATTR(probability, ulong);
354	FAULT_CONFIGFS_ATTR(interval, ulong);
355	FAULT_CONFIGFS_ATTR(times, atomic_t);
356	FAULT_CONFIGFS_ATTR(space, atomic_t);
357	FAULT_CONFIGFS_ATTR(verbose, ulong);
358	FAULT_CONFIGFS_ATTR_NAMED(ratelimit_interval, "verbose_ratelimit_interval_ms",
359	ratelimit_state.interval, uint);
360	FAULT_CONFIGFS_ATTR_NAMED(ratelimit_burst, "verbose_ratelimit_burst",
361	ratelimit_state.burst, uint);
362	FAULT_CONFIGFS_ATTR_NAMED(task_filter, "task-filter", task_filter, bool);
363
364	#ifdef CONFIG_FAULT_INJECTION_STACKTRACE_FILTER
365
366	static ssize_t fault_stacktrace_depth_show(struct config_item item, char page)
367	{
368	return fault_ulong_attr_show(to_fault_config(item)->attr.stacktrace_depth, page);
369	}
370
371	static ssize_t fault_stacktrace_depth_store(struct config_item item, const char page,
372	size_t count)
373	{
374	int result;
375	unsigned long tmp;
376
377	result = kstrtoul(page, 0, &tmp);
378	if (result < 0)
379	return result;
380
381	to_fault_config(item)->attr.stacktrace_depth =
382	min_t(unsigned long, tmp, MAX_STACK_TRACE_DEPTH);
383
384	return count;
385	}
386
387	CONFIGFS_ATTR_NAMED(fault_, stacktrace_depth, "stacktrace-depth");
388
389	static ssize_t fault_xul_attr_show(unsigned long val, char *page)
390	{
391	return snprintf(page, PAGE_SIZE,
392	sizeof(val) == sizeof(u32) ? "0x%08lx\n" : "0x%016lx\n", val);
393	}
394
395	static ssize_t fault_xul_attr_store(unsigned long val, const char page, size_t count)
396	{
397	return fault_ulong_attr_store(val, page, count);
398	}
399
400	FAULT_CONFIGFS_ATTR_NAMED(require_start, "require-start", require_start, xul);
401	FAULT_CONFIGFS_ATTR_NAMED(require_end, "require-end", require_end, xul);
402	FAULT_CONFIGFS_ATTR_NAMED(reject_start, "reject-start", reject_start, xul);
403	FAULT_CONFIGFS_ATTR_NAMED(reject_end, "reject-end", reject_end, xul);
404
405	#endif /* CONFIG_FAULT_INJECTION_STACKTRACE_FILTER */
406
407	static struct configfs_attribute *fault_config_attrs[] = {
408	&fault_attr_probability,
409	&fault_attr_interval,
410	&fault_attr_times,
411	&fault_attr_space,
412	&fault_attr_verbose,
413	&fault_attr_ratelimit_interval,
414	&fault_attr_ratelimit_burst,
415	&fault_attr_task_filter,
416	#ifdef CONFIG_FAULT_INJECTION_STACKTRACE_FILTER
417	&fault_attr_stacktrace_depth,
418	&fault_attr_require_start,
419	&fault_attr_require_end,
420	&fault_attr_reject_start,
421	&fault_attr_reject_end,
422	#endif /* CONFIG_FAULT_INJECTION_STACKTRACE_FILTER */
423	NULL,
424	};
425
426	static const struct config_item_type fault_config_type = {
427	.ct_attrs = fault_config_attrs,
428	.ct_owner = THIS_MODULE,
429	};
430
431	void fault_config_init(struct fault_config config, const char name)
432	{
433	config_group_init_type_name(&config->group, name, &fault_config_type);
434	}
435	EXPORT_SYMBOL_GPL(fault_config_init);
436
437	#endif /* CONFIG_FAULT_INJECTION_CONFIGFS */