1 // SPDX-License-Identifier: GPL-2.0 2 3 /* 4 * Fault injection ublk target. Hack this up however you like for 5 * testing specific behaviors of ublk_drv. Currently is a null target 6 * with a configurable delay before completing each I/O. This delay can 7 * be used to test ublk_drv's handling of I/O outstanding to the ublk 8 * server when it dies. 9 */ 10 11 #include "kublk.h" 12 13 static int ublk_fault_inject_tgt_init(const struct dev_ctx *ctx, 14 struct ublk_dev *dev) 15 { 16 const struct ublksrv_ctrl_dev_info *info = &dev->dev_info; 17 unsigned long dev_size = 250UL << 30; 18 19 dev->tgt.dev_size = dev_size; 20 dev->tgt.params = (struct ublk_params) { 21 .types = UBLK_PARAM_TYPE_BASIC, 22 .basic = { 23 .logical_bs_shift = 9, 24 .physical_bs_shift = 12, 25 .io_opt_shift = 12, 26 .io_min_shift = 9, 27 .max_sectors = info->max_io_buf_bytes >> 9, 28 .dev_sectors = dev_size >> 9, 29 }, 30 }; 31 32 dev->private_data = (void *)(unsigned long)(ctx->fault_inject.delay_us * 1000); 33 return 0; 34 } 35 36 static int ublk_fault_inject_queue_io(struct ublk_queue *q, int tag) 37 { 38 const struct ublksrv_io_desc *iod = ublk_get_iod(q, tag); 39 struct io_uring_sqe *sqe; 40 struct __kernel_timespec ts = { 41 .tv_nsec = (long long)q->dev->private_data, 42 }; 43 44 ublk_queue_alloc_sqes(q, &sqe, 1); 45 io_uring_prep_timeout(sqe, &ts, 1, 0); 46 sqe->user_data = build_user_data(tag, ublksrv_get_op(iod), 0, 1); 47 48 ublk_queued_tgt_io(q, tag, 1); 49 50 return 0; 51 } 52 53 static void ublk_fault_inject_tgt_io_done(struct ublk_queue *q, int tag, 54 const struct io_uring_cqe *cqe) 55 { 56 const struct ublksrv_io_desc *iod = ublk_get_iod(q, tag); 57 58 if (cqe->res != -ETIME) 59 ublk_err("%s: unexpected cqe res %d\n", __func__, cqe->res); 60 61 if (ublk_completed_tgt_io(q, tag)) 62 ublk_complete_io(q, tag, iod->nr_sectors << 9); 63 else 64 ublk_err("%s: io not complete after 1 cqe\n", __func__); 65 } 66 67 static void ublk_fault_inject_cmd_line(struct dev_ctx *ctx, int argc, char *argv[]) 68 { 69 static const struct option longopts[] = { 70 { "delay_us", 1, NULL, 0 }, 71 { 0, 0, 0, 0 } 72 }; 73 int option_idx, opt; 74 75 ctx->fault_inject.delay_us = 0; 76 while ((opt = getopt_long(argc, argv, "", 77 longopts, &option_idx)) != -1) { 78 switch (opt) { 79 case 0: 80 if (!strcmp(longopts[option_idx].name, "delay_us")) 81 ctx->fault_inject.delay_us = strtoll(optarg, NULL, 10); 82 } 83 } 84 } 85 86 static void ublk_fault_inject_usage(const struct ublk_tgt_ops *ops) 87 { 88 printf("\tfault_inject: [--delay_us us (default 0)]\n"); 89 } 90 91 const struct ublk_tgt_ops fault_inject_tgt_ops = { 92 .name = "fault_inject", 93 .init_tgt = ublk_fault_inject_tgt_init, 94 .queue_io = ublk_fault_inject_queue_io, 95 .tgt_io_done = ublk_fault_inject_tgt_io_done, 96 .parse_cmd_line = ublk_fault_inject_cmd_line, 97 .usage = ublk_fault_inject_usage, 98 }; 99