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_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 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 57 void nvme_should_fail(struct request *req) 58 { 59 struct gendisk *disk = req->q->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