#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/interrupt.h>
+#include <linux/stacktrace.h>
+#include <linux/kallsyms.h>
#include <linux/fault-inject.h>
/*
#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_interrupt() && task->make_it_fail;
+}
+
+#define MAX_STACK_TRACE_DEPTH 32
+
+#ifdef CONFIG_FAULT_INJECTION_STACKTRACE_FILTER
+
+static bool fail_stacktrace(struct fault_attr *attr)
+{
+ struct stack_trace trace;
+ int depth = attr->stacktrace_depth;
+ unsigned long entries[MAX_STACK_TRACE_DEPTH];
+ int n;
+ bool found = (attr->require_start == 0 && attr->require_end == ULONG_MAX);
+
+ if (depth == 0)
+ return found;
+
+ trace.nr_entries = 0;
+ trace.entries = entries;
+ trace.max_entries = depth;
+ trace.skip = 1;
+
+ save_stack_trace(&trace);
+ for (n = 0; n < trace.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/
*/
-int should_fail(struct fault_attr *attr, ssize_t size)
+bool should_fail(struct fault_attr *attr, ssize_t size)
{
+ if (attr->task_filter && !fail_task(attr, current))
+ return false;
+
if (atomic_read(&attr->times) == 0)
- return 0;
+ return false;
if (atomic_read(&attr->space) > size) {
atomic_sub(size, &attr->space);
- return 0;
+ return false;
}
if (attr->interval > 1) {
attr->count++;
if (attr->count % attr->interval)
- return 0;
+ return false;
}
- if (attr->probability > random32() % 100)
- goto fail;
+ if (attr->probability <= random32() % 100)
+ return false;
- return 0;
+ if (!fail_stacktrace(attr))
+ return false;
-fail:
fail_dump(attr);
if (atomic_read(&attr->times) != -1)
atomic_dec_not_zero(&attr->times);
- return 1;
+ return true;
}
#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
-static void debugfs_ul_set(void *data, u64 val)
+static int debugfs_ul_set(void *data, u64 val)
{
*(unsigned long *)data = val;
+ return 0;
}
-static u64 debugfs_ul_get(void *data)
+#ifdef CONFIG_FAULT_INJECTION_STACKTRACE_FILTER
+static int debugfs_ul_set_MAX_STACK_TRACE_DEPTH(void *data, u64 val)
{
- return *(unsigned long *)data;
+ *(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;
+ return 0;
}
DEFINE_SIMPLE_ATTRIBUTE(fops_ul, debugfs_ul_get, debugfs_ul_set, "%llu\n");
return debugfs_create_file(name, mode, parent, value, &fops_ul);
}
-static void debugfs_atomic_t_set(void *data, u64 val)
+#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)
{
atomic_set((atomic_t *)data, val);
+ return 0;
}
-static u64 debugfs_atomic_t_get(void *data)
+static int debugfs_atomic_t_get(void *data, u64 *val)
{
- return atomic_read((atomic_t *)data);
+ *val = atomic_read((atomic_t *)data);
+ return 0;
}
DEFINE_SIMPLE_ATTRIBUTE(fops_atomic_t, debugfs_atomic_t_get,
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));
attr->dentries.verbose_file =
debugfs_create_ul("verbose", mode, dir, &attr->verbose);
- 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 = 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)
+ 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)
goto fail;
+#endif /* CONFIG_FAULT_INJECTION_STACKTRACE_FILTER */
+
return 0;
fail:
cleanup_fault_attr_dentries(attr);
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff