1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * fault injection support for nvme.
4 *
5 * Copyright (c) 2018, Oracle and/or its affiliates
6 */
7
8 #include <linux/moduleparam.h>
9 #include "nvme.h"
10
11 static DECLARE_FAULT_ATTR(fail_default_attr);
12 /* optional fault injection attributes boot time option:
13 * nvme_core.fail_request=<interval>,<probability>,<space>,<times>
14 */
15 static char *fail_request;
16 module_param(fail_request, charp, 0000);
17
nvme_fault_inject_init(struct nvme_fault_inject * fault_inj,const char * dev_name)18 void nvme_fault_inject_init(struct nvme_fault_inject *fault_inj,
19 const char *dev_name)
20 {
21 struct dentry *dir, *parent;
22 struct fault_attr *attr = &fault_inj->attr;
23
24 /* set default fault injection attribute */
25 if (fail_request)
26 setup_fault_attr(&fail_default_attr, fail_request);
27
28 /* create debugfs directory and attribute */
29 parent = debugfs_create_dir(dev_name, NULL);
30 if (!parent) {
31 pr_warn("%s: failed to create debugfs directory\n", dev_name);
32 return;
33 }
34
35 *attr = fail_default_attr;
36 dir = fault_create_debugfs_attr("fault_inject", parent, attr);
37 if (IS_ERR(dir)) {
38 pr_warn("%s: failed to create debugfs attr\n", dev_name);
39 debugfs_remove_recursive(parent);
40 return;
41 }
42 fault_inj->parent = parent;
43
44 /* create debugfs for status code and dont_retry */
45 fault_inj->status = NVME_SC_INVALID_OPCODE;
46 fault_inj->dont_retry = true;
47 debugfs_create_x16("status", 0600, dir, &fault_inj->status);
48 debugfs_create_bool("dont_retry", 0600, dir, &fault_inj->dont_retry);
49 }
50
nvme_fault_inject_fini(struct nvme_fault_inject * fault_inject)51 void nvme_fault_inject_fini(struct nvme_fault_inject *fault_inject)
52 {
53 /* remove debugfs directories */
54 debugfs_remove_recursive(fault_inject->parent);
55 }
56
nvme_should_fail(struct request * req)57 void nvme_should_fail(struct request *req)
58 {
59 struct gendisk *disk = req->rq_disk;
60 struct nvme_fault_inject *fault_inject = NULL;
61 u16 status;
62
63 if (disk) {
64 struct nvme_ns *ns = disk->private_data;
65
66 if (ns)
67 fault_inject = &ns->fault_inject;
68 else
69 WARN_ONCE(1, "No namespace found for request\n");
70 } else {
71 fault_inject = &nvme_req(req)->ctrl->fault_inject;
72 }
73
74 if (fault_inject && should_fail(&fault_inject->attr, 1)) {
75 /* inject status code and DNR bit */
76 status = fault_inject->status;
77 if (fault_inject->dont_retry)
78 status |= NVME_SC_DNR;
79 nvme_req(req)->status = status;
80 }
81 }
82 EXPORT_SYMBOL_GPL(nvme_should_fail);
83