1 files changed, 53 insertions, 134 deletions

diff --git a/lib/fault-inject.c b/lib/fault-inject.c
index f97af55bdd96..d7d501ea856d 100644
--- a/lib/fault-inject.c
+++ b/lib/fault-inject.c
@@ -1,20 +1,20 @@
 #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/module.h>
+#include <linux/export.h>
 #include <linux/interrupt.h>
 #include <linux/stacktrace.h>
-#include <linux/kallsyms.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 __init setup_fault_attr(struct fault_attr *attr, char *str)
+int setup_fault_attr(struct fault_attr *attr, char *str)
 {
 	unsigned long probability;
 	unsigned long interval;
@@ -36,6 +36,7 @@ int __init setup_fault_attr(struct fault_attr *attr, char *str)
 
 	return 1;
 }
+EXPORT_SYMBOL_GPL(setup_fault_attr);
 
 static void fail_dump(struct fault_attr *attr)
 {
@@ -100,6 +101,10 @@ static inline bool fail_stacktrace(struct fault_attr *attr)
 
 bool should_fail(struct fault_attr *attr, ssize_t size)
 {
+	/* 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;
 
@@ -117,7 +122,7 @@ bool should_fail(struct fault_attr *attr, ssize_t size)
 			return false;
 	}
 
-	if (attr->probability <= random32() % 100)
+	if (attr->probability <= prandom_u32() % 100)
 		return false;
 
 	if (!fail_stacktrace(attr))
@@ -130,6 +135,7 @@ bool should_fail(struct fault_attr *attr, ssize_t size)
 
 	return true;
 }
+EXPORT_SYMBOL_GPL(should_fail);
 
 #ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
 
@@ -139,16 +145,6 @@ static int debugfs_ul_set(void *data, u64 val)
 	return 0;
 }
 
-#ifdef CONFIG_FAULT_INJECTION_STACKTRACE_FILTER
-static int debugfs_ul_set_MAX_STACK_TRACE_DEPTH(void *data, u64 val)
-{
-	*(unsigned long *)data =
-		val < MAX_STACK_TRACE_DEPTH ?
-		val : MAX_STACK_TRACE_DEPTH;
-	return 0;
-}
-#endif /* CONFIG_FAULT_INJECTION_STACKTRACE_FILTER */
-
 static int debugfs_ul_get(void *data, u64 *val)
 {
 	*val = *(unsigned long *)data;
@@ -157,158 +153,81 @@ static int debugfs_ul_get(void *data, u64 *val)
 
 DEFINE_SIMPLE_ATTRIBUTE(fops_ul, debugfs_ul_get, debugfs_ul_set, "%llu\n");
 
-static struct dentry *debugfs_create_ul(const char *name, mode_t mode,
+static struct dentry *debugfs_create_ul(const char *name, umode_t mode,
 				struct dentry *parent, unsigned long *value)
 {
 	return debugfs_create_file(name, mode, parent, value, &fops_ul);
 }
 
 #ifdef CONFIG_FAULT_INJECTION_STACKTRACE_FILTER
-DEFINE_SIMPLE_ATTRIBUTE(fops_ul_MAX_STACK_TRACE_DEPTH, debugfs_ul_get,
-			debugfs_ul_set_MAX_STACK_TRACE_DEPTH, "%llu\n");
-
-static struct dentry *debugfs_create_ul_MAX_STACK_TRACE_DEPTH(
-	const char *name, mode_t mode,
-	struct dentry *parent, unsigned long *value)
-{
-	return debugfs_create_file(name, mode, parent, value,
-				   &fops_ul_MAX_STACK_TRACE_DEPTH);
-}
-#endif /* CONFIG_FAULT_INJECTION_STACKTRACE_FILTER */
 
-static int debugfs_atomic_t_set(void *data, u64 val)
+static int debugfs_stacktrace_depth_set(void *data, u64 val)
 {
-	atomic_set((atomic_t *)data, val);
-	return 0;
-}
+	*(unsigned long *)data =
+		min_t(unsigned long, val, MAX_STACK_TRACE_DEPTH);
 
-static int debugfs_atomic_t_get(void *data, u64 *val)
-{
-	*val = atomic_read((atomic_t *)data);
 	return 0;
 }
 
-DEFINE_SIMPLE_ATTRIBUTE(fops_atomic_t, debugfs_atomic_t_get,
-			debugfs_atomic_t_set, "%lld\n");
+DEFINE_SIMPLE_ATTRIBUTE(fops_stacktrace_depth, debugfs_ul_get,
+			debugfs_stacktrace_depth_set, "%llu\n");
 
-static struct dentry *debugfs_create_atomic_t(const char *name, mode_t mode,
-				struct dentry *parent, atomic_t *value)
+static struct dentry *debugfs_create_stacktrace_depth(
+	const char *name, umode_t mode,
+	struct dentry *parent, unsigned long *value)
 {
-	return debugfs_create_file(name, mode, parent, value, &fops_atomic_t);
+	return debugfs_create_file(name, mode, parent, value,
+				   &fops_stacktrace_depth);
 }
 
-void cleanup_fault_attr_dentries(struct fault_attr *attr)
-{
-	debugfs_remove(attr->dentries.probability_file);
-	attr->dentries.probability_file = NULL;
-
-	debugfs_remove(attr->dentries.interval_file);
-	attr->dentries.interval_file = NULL;
-
-	debugfs_remove(attr->dentries.times_file);
-	attr->dentries.times_file = NULL;
-
-	debugfs_remove(attr->dentries.space_file);
-	attr->dentries.space_file = NULL;
-
-	debugfs_remove(attr->dentries.verbose_file);
-	attr->dentries.verbose_file = NULL;
-
-	debugfs_remove(attr->dentries.task_filter_file);
-	attr->dentries.task_filter_file = NULL;
-
-#ifdef CONFIG_FAULT_INJECTION_STACKTRACE_FILTER
-
-	debugfs_remove(attr->dentries.stacktrace_depth_file);
-	attr->dentries.stacktrace_depth_file = NULL;
-
-	debugfs_remove(attr->dentries.require_start_file);
-	attr->dentries.require_start_file = NULL;
-
-	debugfs_remove(attr->dentries.require_end_file);
-	attr->dentries.require_end_file = NULL;
-
-	debugfs_remove(attr->dentries.reject_start_file);
-	attr->dentries.reject_start_file = NULL;
-
-	debugfs_remove(attr->dentries.reject_end_file);
-	attr->dentries.reject_end_file = NULL;
-
 #endif /* CONFIG_FAULT_INJECTION_STACKTRACE_FILTER */
 
-	if (attr->dentries.dir)
-		WARN_ON(!simple_empty(attr->dentries.dir));
-
-	debugfs_remove(attr->dentries.dir);
-	attr->dentries.dir = NULL;
-}
-
-int init_fault_attr_dentries(struct fault_attr *attr, const char *name)
+struct dentry *fault_create_debugfs_attr(const char *name,
+			struct dentry *parent, struct fault_attr *attr)
 {
-	mode_t mode = S_IFREG | S_IRUSR | S_IWUSR;
+	umode_t mode = S_IFREG | S_IRUSR | S_IWUSR;
 	struct dentry *dir;
 
-	memset(&attr->dentries, 0, sizeof(attr->dentries));
-
-	dir = debugfs_create_dir(name, NULL);
+	dir = debugfs_create_dir(name, parent);
 	if (!dir)
-		goto fail;
-	attr->dentries.dir = dir;
-
-	attr->dentries.probability_file =
-		debugfs_create_ul("probability", mode, dir, &attr->probability);
-
-	attr->dentries.interval_file =
-		debugfs_create_ul("interval", mode, dir, &attr->interval);
-
-	attr->dentries.times_file =
-		debugfs_create_atomic_t("times", mode, dir, &attr->times);
+		return ERR_PTR(-ENOMEM);
 
-	attr->dentries.space_file =
-		debugfs_create_atomic_t("space", mode, dir, &attr->space);
-
-	attr->dentries.verbose_file =
-		debugfs_create_ul("verbose", mode, dir, &attr->verbose);
-
-	attr->dentries.task_filter_file = debugfs_create_bool("task-filter",
-						mode, dir, &attr->task_filter);
-
-	if (!attr->dentries.probability_file || !attr->dentries.interval_file ||
-	    !attr->dentries.times_file || !attr->dentries.space_file ||
-	    !attr->dentries.verbose_file || !attr->dentries.task_filter_file)
+	if (!debugfs_create_ul("probability", mode, dir, &attr->probability))
+		goto fail;
+	if (!debugfs_create_ul("interval", mode, dir, &attr->interval))
+		goto fail;
+	if (!debugfs_create_atomic_t("times", mode, dir, &attr->times))
+		goto fail;
+	if (!debugfs_create_atomic_t("space", mode, dir, &attr->space))
+		goto fail;
+	if (!debugfs_create_ul("verbose", mode, dir, &attr->verbose))
+		goto fail;
+	if (!debugfs_create_bool("task-filter", mode, dir, &attr->task_filter))
 		goto fail;
 
 #ifdef CONFIG_FAULT_INJECTION_STACKTRACE_FILTER
 
-	attr->dentries.stacktrace_depth_file =
-		debugfs_create_ul_MAX_STACK_TRACE_DEPTH(
-			"stacktrace-depth", mode, dir, &attr->stacktrace_depth);
-
-	attr->dentries.require_start_file =
-		debugfs_create_ul("require-start", mode, dir, &attr->require_start);
-
-	attr->dentries.require_end_file =
-		debugfs_create_ul("require-end", mode, dir, &attr->require_end);
-
-	attr->dentries.reject_start_file =
-		debugfs_create_ul("reject-start", mode, dir, &attr->reject_start);
-
-	attr->dentries.reject_end_file =
-		debugfs_create_ul("reject-end", mode, dir, &attr->reject_end);
-
-	if (!attr->dentries.stacktrace_depth_file ||
-	    !attr->dentries.require_start_file ||
-	    !attr->dentries.require_end_file ||
-	    !attr->dentries.reject_start_file ||
-	    !attr->dentries.reject_end_file)
+	if (!debugfs_create_stacktrace_depth("stacktrace-depth", mode, dir,
+				&attr->stacktrace_depth))
+		goto fail;
+	if (!debugfs_create_ul("require-start", mode, dir,
+				&attr->require_start))
+		goto fail;
+	if (!debugfs_create_ul("require-end", mode, dir, &attr->require_end))
+		goto fail;
+	if (!debugfs_create_ul("reject-start", mode, dir, &attr->reject_start))
+		goto fail;
+	if (!debugfs_create_ul("reject-end", mode, dir, &attr->reject_end))
 		goto fail;
 
 #endif /* CONFIG_FAULT_INJECTION_STACKTRACE_FILTER */
 
-	return 0;
+	return dir;
 fail:
-	cleanup_fault_attr_dentries(attr);
-	return -ENOMEM;
+	debugfs_remove_recursive(dir);
+
+	return ERR_PTR(-ENOMEM);
 }
+EXPORT_SYMBOL_GPL(fault_create_debugfs_attr);
 
 #endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */