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 
ublk_fault_inject_tgt_init(const struct dev_ctx * ctx,struct ublk_dev * dev)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 
ublk_fault_inject_queue_io(struct ublk_queue * q,int tag)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 
ublk_fault_inject_tgt_io_done(struct ublk_queue * q,int tag,const struct io_uring_cqe * cqe)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 
ublk_fault_inject_cmd_line(struct dev_ctx * ctx,int argc,char * argv[])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 
ublk_fault_inject_usage(const struct ublk_tgt_ops * ops)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