aboutsummaryrefslogtreecommitdiffstats
path: root/fs/nfsd/fault_inject.c
blob: 6dfede6d172aa276ba99544cf561cf4744220ff7 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (c) 2011 Bryan Schumaker <bjschuma@netapp.com>
 *
 * Uses debugfs to create fault injection points for client testing
 */

#include <linux/types.h>
#include <linux/fs.h>
#include <linux/debugfs.h>
#include <linux/module.h>
#include <linux/nsproxy.h>
#include <linux/sunrpc/addr.h>
#include <linux/uaccess.h>

#include "state.h"
#include "netns.h"

struct nfsd_fault_inject_op {
	char *file;
	u64 (*get)(void);
	u64 (*set_val)(u64);
	u64 (*set_clnt)(struct sockaddr_storage *, size_t);
};

static struct dentry *debug_dir;

static ssize_t fault_inject_read(struct file *file, char __user *buf,
				 size_t len, loff_t *ppos)
{
	static u64 val;
	char read_buf[25];
	size_t size;
	loff_t pos = *ppos;
	struct nfsd_fault_inject_op *op = file_inode(file)->i_private;

	if (!pos)
		val = op->get();
	size = scnprintf(read_buf, sizeof(read_buf), "%llu\n", val);

	return simple_read_from_buffer(buf, len, ppos, read_buf, size);
}

static ssize_t fault_inject_write(struct file *file, const char __user *buf,
				  size_t len, loff_t *ppos)
{
	char write_buf[INET6_ADDRSTRLEN];
	size_t size = min(sizeof(write_buf) - 1, len);
	struct net *net = current->nsproxy->net_ns;
	struct sockaddr_storage sa;
	struct nfsd_fault_inject_op *op = file_inode(file)->i_private;
	u64 val;
	char *nl;

	if (copy_from_user(write_buf, buf, size))
		return -EFAULT;
	write_buf[size] = '\0';

	/* Deal with any embedded newlines in the string */
	nl = strchr(write_buf, '\n');
	if (nl) {
		size = nl - write_buf;
		*nl = '\0';
	}

	size = rpc_pton(net, write_buf, size, (struct sockaddr *)&sa, sizeof(sa));
	if (size > 0) {
		val = op->set_clnt(&sa, size);
		if (val)
			pr_info("NFSD [%s]: Client %s had %llu state object(s)\n",
				op->file, write_buf, val);
	} else {
		val = simple_strtoll(write_buf, NULL, 0);
		if (val == 0)
			pr_info("NFSD Fault Injection: %s (all)", op->file);
		else
			pr_info("NFSD Fault Injection: %s (n = %llu)",
				op->file, val);
		val = op->set_val(val);
		pr_info("NFSD: %s: found %llu", op->file, val);
	}
	return len; /* on success, claim we got the whole input */
}

static const struct file_operations fops_nfsd = {
	.owner   = THIS_MODULE,
	.read    = fault_inject_read,
	.write   = fault_inject_write,
};

void nfsd_fault_inject_cleanup(void)
{
	debugfs_remove_recursive(debug_dir);
}

static struct nfsd_fault_inject_op inject_ops[] = {
	{
		.file     = "forget_clients",
		.get	  = nfsd_inject_print_clients,
		.set_val  = nfsd_inject_forget_clients,
		.set_clnt = nfsd_inject_forget_client,
	},
	{
		.file     = "forget_locks",
		.get	  = nfsd_inject_print_locks,
		.set_val  = nfsd_inject_forget_locks,
		.set_clnt = nfsd_inject_forget_client_locks,
	},
	{
		.file     = "forget_openowners",
		.get	  = nfsd_inject_print_openowners,
		.set_val  = nfsd_inject_forget_openowners,
		.set_clnt = nfsd_inject_forget_client_openowners,
	},
	{
		.file     = "forget_delegations",
		.get	  = nfsd_inject_print_delegations,
		.set_val  = nfsd_inject_forget_delegations,
		.set_clnt = nfsd_inject_forget_client_delegations,
	},
	{
		.file     = "recall_delegations",
		.get	  = nfsd_inject_print_delegations,
		.set_val  = nfsd_inject_recall_delegations,
		.set_clnt = nfsd_inject_recall_client_delegations,
	},
};

#define NUM_INJECT_OPS (sizeof(inject_ops)/sizeof(struct nfsd_fault_inject_op))

int nfsd_fault_inject_init(void)
{
	unsigned int i;
	struct nfsd_fault_inject_op *op;
	umode_t mode = S_IFREG | S_IRUSR | S_IWUSR;

	debug_dir = debugfs_create_dir("nfsd", NULL);
	if (!debug_dir)
		goto fail;

	for (i = 0; i < NUM_INJECT_OPS; i++) {
		op = &inject_ops[i];
		if (!debugfs_create_file(op->file, mode, debug_dir, op, &fops_nfsd))
			goto fail;
	}
	return 0;

fail:
	nfsd_fault_inject_cleanup();
	return -ENOMEM;
}