X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=lib%2Ffault-inject.c;h=7e65af70635e4c6db2be536f7e387dedb1daf1d2;hb=e0c8233622cbd49d171bc57b60e725f2fb748750;hp=244782940349ba8aea5c9d4750bfc028a506b9a0;hpb=08b3df2d16cbebf7d72c09dcbc071696c14d07e3;p=safe%2Fjmp%2Flinux-2.6

diff --git a/lib/fault-inject.c b/lib/fault-inject.c
index 2447829..7e65af7 100644
--- a/lib/fault-inject.c
+++ b/lib/fault-inject.c
@@ -1,12 +1,12 @@
 #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/unwind.h>
 #include <linux/stacktrace.h>
 #include <linux/kallsyms.h>
 #include <linux/fault-inject.h>
@@ -53,37 +53,9 @@ static bool fail_task(struct fault_attr *attr, struct task_struct *task)
 	return !in_interrupt() && task->make_it_fail;
 }
 
-#ifdef CONFIG_STACK_UNWIND
+#define MAX_STACK_TRACE_DEPTH 32
 
-static asmlinkage int fail_stacktrace_callback(struct unwind_frame_info *info,
-						void *arg)
-{
-	int depth;
-	struct fault_attr *attr = arg;
-	bool found = (attr->require_start == 0 && attr->require_end == ULONG_MAX);
-
-	for (depth = 0; depth < attr->stacktrace_depth
-			&& unwind(info) == 0 && UNW_PC(info); depth++) {
-		if (arch_unw_user_mode(info))
-			break;
-		if (attr->reject_start <= UNW_PC(info) &&
-			       UNW_PC(info) < attr->reject_end)
-			return false;
-		if (attr->require_start <= UNW_PC(info) &&
-			       UNW_PC(info) < attr->require_end)
-			found = true;
-	}
-	return found;
-}
-
-static bool fail_stacktrace(struct fault_attr *attr)
-{
-	struct unwind_frame_info info;
-
-	return unwind_init_running(&info, fail_stacktrace_callback, attr);
-}
-
-#elif defined(CONFIG_STACKTRACE)
+#ifdef CONFIG_FAULT_INJECTION_STACKTRACE_FILTER
 
 static bool fail_stacktrace(struct fault_attr *attr)
 {
@@ -98,12 +70,10 @@ static bool fail_stacktrace(struct fault_attr *attr)
 
 	trace.nr_entries = 0;
 	trace.entries = entries;
-	trace.max_entries = (depth < MAX_STACK_TRACE_DEPTH) ?
-				depth : MAX_STACK_TRACE_DEPTH;
+	trace.max_entries = depth;
 	trace.skip = 1;
-	trace.all_contexts = 0;
 
-	save_stack_trace(&trace, NULL);
+	save_stack_trace(&trace);
 	for (n = 0; n < trace.nr_entries; n++) {
 		if (attr->reject_start <= entries[n] &&
 			       entries[n] < attr->reject_end)
@@ -119,17 +89,10 @@ static bool fail_stacktrace(struct fault_attr *attr)
 
 static inline bool fail_stacktrace(struct fault_attr *attr)
 {
-	static bool firsttime = true;
-
-	if (firsttime) {
-		printk(KERN_WARNING
-		"This architecture does not implement save_stack_trace()\n");
-		firsttime = false;
-	}
-	return false;
+	return true;
 }
 
-#endif
+#endif /* CONFIG_FAULT_INJECTION_STACKTRACE_FILTER */
 
 /*
  * This code is stolen from failmalloc-1.0
@@ -141,9 +104,6 @@ bool should_fail(struct fault_attr *attr, ssize_t size)
 	if (attr->task_filter && !fail_task(attr, current))
 		return false;
 
-	if (!fail_stacktrace(attr))
-		return false;
-
 	if (atomic_read(&attr->times) == 0)
 		return false;
 
@@ -158,12 +118,12 @@ bool should_fail(struct fault_attr *attr, ssize_t size)
 			return false;
 	}
 
-	if (attr->probability > random32() % 100)
-		goto fail;
+	if (attr->probability <= random32() % 100)
+		return false;
 
-	return false;
+	if (!fail_stacktrace(attr))
+		return false;
 
-fail:
 	fail_dump(attr);
 
 	if (atomic_read(&attr->times) != -1)
@@ -174,14 +134,26 @@ fail:
 
 #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");
@@ -192,14 +164,29 @@ static struct dentry *debugfs_create_ul(const char *name, mode_t mode,
 	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,
@@ -231,6 +218,8 @@ void cleanup_fault_attr_dentries(struct fault_attr *attr)
 	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;
 
@@ -246,6 +235,8 @@ void cleanup_fault_attr_dentries(struct fault_attr *attr)
 	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));
 
@@ -283,9 +274,16 @@ int init_fault_attr_dentries(struct fault_attr *attr, const char *name)
 	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("stacktrace-depth", mode, dir,
-				  &attr->stacktrace_depth);
+		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);
@@ -299,18 +297,15 @@ int init_fault_attr_dentries(struct fault_attr *attr, const char *name)
 	attr->dentries.reject_end_file =
 		debugfs_create_ul("reject-end", mode, dir, &attr->reject_end);
 
-
-	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
-	    || !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 (!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);