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 18 void nvme_fault_inject_init(struct nvme_ns *ns) 19 { 20 struct dentry *dir, *parent; 21 char *name = ns->disk->disk_name; 22 struct nvme_fault_inject *fault_inj = &ns->fault_inject; 23 struct fault_attr *attr = &fault_inj->attr; 24 25 /* set default fault injection attribute */ 26 if (fail_request) 27 setup_fault_attr(&fail_default_attr, fail_request); 28 29 /* create debugfs directory and attribute */ 30 parent = debugfs_create_dir(name, NULL); 31 if (!parent) { 32 pr_warn("%s: failed to create debugfs directory\n", name); 33 return; 34 } 35 36 *attr = fail_default_attr; 37 dir = fault_create_debugfs_attr("fault_inject", parent, attr); 38 if (IS_ERR(dir)) { 39 pr_warn("%s: failed to create debugfs attr\n", name); 40 debugfs_remove_recursive(parent); 41 return; 42 } 43 ns->fault_inject.parent = parent; 44 45 /* create debugfs for status code and dont_retry */ 46 fault_inj->status = NVME_SC_INVALID_OPCODE; 47 fault_inj->dont_retry = true; 48 debugfs_create_x16("status", 0600, dir, &fault_inj->status); 49 debugfs_create_bool("dont_retry", 0600, dir, &fault_inj->dont_retry); 50 } 51 52 void nvme_fault_inject_fini(struct nvme_ns *ns) 53 { 54 /* remove debugfs directories */ 55 debugfs_remove_recursive(ns->fault_inject.parent); 56 } 57 58 void nvme_should_fail(struct request *req) 59 { 60 struct gendisk *disk = req->rq_disk; 61 struct nvme_ns *ns = NULL; 62 u16 status; 63 64 /* 65 * make sure this request is coming from a valid namespace 66 */ 67 if (!disk) 68 return; 69 70 ns = disk->private_data; 71 if (ns && should_fail(&ns->fault_inject.attr, 1)) { 72 /* inject status code and DNR bit */ 73 status = ns->fault_inject.status; 74 if (ns->fault_inject.dont_retry) 75 status |= NVME_SC_DNR; 76 nvme_req(req)->status = status; 77 } 78 } 79 EXPORT_SYMBOL_GPL(nvme_should_fail); 80