linux-master/kernel/fail_function.c

58 	struct fei_attr *attr;
60 	attr = kzalloc(sizeof(*attr), GFP_KERNEL);
61 	if (attr) {
62 		attr->kp.symbol_name = kstrdup(sym, GFP_KERNEL);
63 		if (!attr->kp.symbol_name) {
64 			kfree(attr);
67 		attr->kp.pre_handler = fei_kprobe_handler;
68 		attr->kp.post_handler = fei_post_handler;
69 		attr->retval = adjust_error_retval(addr, 0);
70 		INIT_LIST_HEAD(&attr->list);
72 	return attr;
75 static void fei_attr_free(struct fei_attr *attr)
77 	if (attr) {
78 		kfree(attr->kp.symbol_name);
79 		kfree(attr);
85 	struct fei_attr *attr;
87 	list_for_each_entry(attr, &fei_attr_list, list) {
88 		if (!strcmp(attr->kp.symbol_name, sym))
89 			return attr;
97 	struct fei_attr *attr;
99 	list_for_each_entry(attr, &fei_attr_list, list) {
100 		if (attr == _attr)
109 	struct fei_attr *attr = data;
116 	 * It is safer to check the attr is still valid before accessing
119 	if (!fei_attr_is_valid(attr)) {
124 	if (attr->kp.addr) {
125 		if (adjust_error_retval((unsigned long)attr->kp.addr,
130 		attr->retval = val;
139 	struct fei_attr *attr = data;
143 	/* Here we also validate @attr to ensure it still exists. */
144 	if (!fei_attr_is_valid(attr))
147 		*val = attr->retval;
155 static void fei_debugfs_add_attr(struct fei_attr *attr)
159 	dir = debugfs_create_dir(attr->kp.symbol_name, fei_debugfs_dir);
161 	debugfs_create_file("retval", 0600, dir, attr, &fei_retval_ops);
164 static void fei_debugfs_remove_attr(struct fei_attr *attr)
166 	debugfs_lookup_and_remove(attr->kp.symbol_name, fei_debugfs_dir);
171 	struct fei_attr *attr = container_of(kp, struct fei_attr, kp);
174 		regs_set_return_value(regs, attr->retval);
201 	struct fei_attr *attr = list_entry(v, struct fei_attr, list);
203 	seq_printf(m, "%ps\n", attr->kp.addr);
219 static void fei_attr_remove(struct fei_attr *attr)
221 	fei_debugfs_remove_attr(attr);
222 	unregister_kprobe(&attr->kp);
223 	list_del(&attr->list);
224 	fei_attr_free(attr);
229 	struct fei_attr *attr, *n;
231 	list_for_each_entry_safe(attr, n, &fei_attr_list, list) {
232 		fei_attr_remove(attr);
239 	struct fei_attr *attr;
264 		attr = fei_attr_lookup(sym + 1);
265 		if (!attr) {
269 		fei_attr_remove(attr);
287 	attr = fei_attr_new(sym, addr);
288 	if (!attr) {
293 	ret = register_kprobe(&attr->kp);
295 		fei_attr_free(attr);
298 	fei_debugfs_add_attr(attr);
299 	list_add_tail(&attr->list, &fei_attr_list);