aboutsummaryrefslogtreecommitdiffstats
path: root/fs/nfsd/fault_inject.c
blob: d620e7f8142903feebabcb2c3cefdf6a5ea2f1de (plain)
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
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
/*
 * 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 <asm/uaccess.h>

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

struct nfsd_fault_inject_op {
	char *file;
	u64 (*forget)(struct nfs4_client *, u64);
	u64 (*print)(struct nfs4_client *, u64);
};

static struct nfsd_fault_inject_op inject_ops[] = {
	{
		.file   = "forget_clients",
		.forget = nfsd_forget_client,
		.print  = nfsd_print_client,
	},
	{
		.file   = "forget_locks",
		.forget = nfsd_forget_client_locks,
		.print  = nfsd_print_client_locks,
	},
	{
		.file   = "forget_openowners",
		.forget = nfsd_forget_client_openowners,
		.print  = nfsd_print_client_openowners,
	},
	{
		.file   = "forget_delegations",
		.forget = nfsd_forget_client_delegations,
		.print  = nfsd_print_client_delegations,
	},
	{
		.file   = "recall_delegations",
		.forget = nfsd_recall_client_delegations,
		.print  = nfsd_print_client_delegations,
	},
};

static long int NUM_INJECT_OPS = sizeof(inject_ops) / sizeof(struct nfsd_fault_inject_op);
static struct dentry *debug_dir;

static void nfsd_inject_set(struct nfsd_fault_inject_op *op, u64 val)
{
	u64 count = 0;

	if (val == 0)
		printk(KERN_INFO "NFSD Fault Injection: %s (all)", op->file);
	else
		printk(KERN_INFO "NFSD Fault Injection: %s (n = %llu)", op->file, val);

	nfs4_lock_state();
	count = nfsd_for_n_state(val, op->forget);
	nfs4_unlock_state();
	printk(KERN_INFO "NFSD: %s: found %llu", op->file, count);
}

static void nfsd_inject_set_client(struct nfsd_fault_inject_op *op,
				   struct sockaddr_storage *addr,
				   size_t addr_size)
{
	char buf[INET6_ADDRSTRLEN];
	struct nfs4_client *clp;
	u64 count;

	nfs4_lock_state();
	clp = nfsd_find_client(addr, addr_size);
	if (clp) {
		count = op->forget(clp, 0);
		rpc_ntop((struct sockaddr *)&clp->cl_addr, buf, sizeof(buf));
		printk(KERN_INFO "NFSD [%s]: Client %s had %llu state object(s)\n", op->file, buf, count);
	}
	nfs4_unlock_state();
}

static void nfsd_inject_get(struct nfsd_fault_inject_op *op, u64 *val)
{
	nfs4_lock_state();
	*val = nfsd_for_n_state(0, op->print);
	nfs4_unlock_state();
}

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, ret;
	loff_t pos = *ppos;

	if (!pos)
		nfsd_inject_get(file_inode(file)->i_private, &val);
	size = scnprintf(read_buf, sizeof(read_buf), "%llu\n", val);

	if (pos < 0)
		return -EINVAL;
	if (pos >= size || !len)
		return 0;
	if (len > size - pos)
		len = size - pos;
	ret = copy_to_user(buf, read_buf + pos, len);
	if (ret == len)
		return -EFAULT;
	len -= ret;
	*ppos = pos + len;
	return len;
}

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;
	u64 val;

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

	size = rpc_pton(net, write_buf, size, (struct sockaddr *)&sa, sizeof(sa));
	if (size > 0)
		nfsd_inject_set_client(file_inode(file)->i_private, &sa, size);
	else {
		val = simple_strtoll(write_buf, NULL, 0);
		nfsd_inject_set(file_inode(file)->i_private, 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);
}

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;
}