1 /*
2 * Copyright (c) 2011 Bryan Schumaker <bjschuma@netapp.com>
3 *
4 * Uses debugfs to create fault injection points for client testing
5 */
6
7 #include <linux/types.h>
8 #include <linux/fs.h>
9 #include <linux/debugfs.h>
10 #include <linux/module.h>
11 #include <linux/nsproxy.h>
12 #include <linux/sunrpc/addr.h>
13 #include <asm/uaccess.h>
14
15 #include "state.h"
16 #include "netns.h"
17
18 struct nfsd_fault_inject_op {
19 char *file;
20 u64 (*get)(void);
21 u64 (*set_val)(u64);
22 u64 (*set_clnt)(struct sockaddr_storage *, size_t);
23 };
24
25 static struct dentry *debug_dir;
26
fault_inject_read(struct file * file,char __user * buf,size_t len,loff_t * ppos)27 static ssize_t fault_inject_read(struct file *file, char __user *buf,
28 size_t len, loff_t *ppos)
29 {
30 static u64 val;
31 char read_buf[25];
32 size_t size;
33 loff_t pos = *ppos;
34 struct nfsd_fault_inject_op *op = file_inode(file)->i_private;
35
36 if (!pos)
37 val = op->get();
38 size = scnprintf(read_buf, sizeof(read_buf), "%llu\n", val);
39
40 return simple_read_from_buffer(buf, len, ppos, read_buf, size);
41 }
42
fault_inject_write(struct file * file,const char __user * buf,size_t len,loff_t * ppos)43 static ssize_t fault_inject_write(struct file *file, const char __user *buf,
44 size_t len, loff_t *ppos)
45 {
46 char write_buf[INET6_ADDRSTRLEN];
47 size_t size = min(sizeof(write_buf) - 1, len);
48 struct net *net = current->nsproxy->net_ns;
49 struct sockaddr_storage sa;
50 struct nfsd_fault_inject_op *op = file_inode(file)->i_private;
51 u64 val;
52 char *nl;
53
54 if (copy_from_user(write_buf, buf, size))
55 return -EFAULT;
56 write_buf[size] = '\0';
57
58 /* Deal with any embedded newlines in the string */
59 nl = strchr(write_buf, '\n');
60 if (nl) {
61 size = nl - write_buf;
62 *nl = '\0';
63 }
64
65 size = rpc_pton(net, write_buf, size, (struct sockaddr *)&sa, sizeof(sa));
66 if (size > 0) {
67 val = op->set_clnt(&sa, size);
68 if (val)
69 pr_info("NFSD [%s]: Client %s had %llu state object(s)\n",
70 op->file, write_buf, val);
71 } else {
72 val = simple_strtoll(write_buf, NULL, 0);
73 if (val == 0)
74 pr_info("NFSD Fault Injection: %s (all)", op->file);
75 else
76 pr_info("NFSD Fault Injection: %s (n = %llu)",
77 op->file, val);
78 val = op->set_val(val);
79 pr_info("NFSD: %s: found %llu", op->file, val);
80 }
81 return len; /* on success, claim we got the whole input */
82 }
83
84 static const struct file_operations fops_nfsd = {
85 .owner = THIS_MODULE,
86 .read = fault_inject_read,
87 .write = fault_inject_write,
88 };
89
nfsd_fault_inject_cleanup(void)90 void nfsd_fault_inject_cleanup(void)
91 {
92 debugfs_remove_recursive(debug_dir);
93 }
94
95 static struct nfsd_fault_inject_op inject_ops[] = {
96 {
97 .file = "forget_clients",
98 .get = nfsd_inject_print_clients,
99 .set_val = nfsd_inject_forget_clients,
100 .set_clnt = nfsd_inject_forget_client,
101 },
102 {
103 .file = "forget_locks",
104 .get = nfsd_inject_print_locks,
105 .set_val = nfsd_inject_forget_locks,
106 .set_clnt = nfsd_inject_forget_client_locks,
107 },
108 {
109 .file = "forget_openowners",
110 .get = nfsd_inject_print_openowners,
111 .set_val = nfsd_inject_forget_openowners,
112 .set_clnt = nfsd_inject_forget_client_openowners,
113 },
114 {
115 .file = "forget_delegations",
116 .get = nfsd_inject_print_delegations,
117 .set_val = nfsd_inject_forget_delegations,
118 .set_clnt = nfsd_inject_forget_client_delegations,
119 },
120 {
121 .file = "recall_delegations",
122 .get = nfsd_inject_print_delegations,
123 .set_val = nfsd_inject_recall_delegations,
124 .set_clnt = nfsd_inject_recall_client_delegations,
125 },
126 };
127
128 #define NUM_INJECT_OPS (sizeof(inject_ops)/sizeof(struct nfsd_fault_inject_op))
129
nfsd_fault_inject_init(void)130 int nfsd_fault_inject_init(void)
131 {
132 unsigned int i;
133 struct nfsd_fault_inject_op *op;
134 umode_t mode = S_IFREG | S_IRUSR | S_IWUSR;
135
136 debug_dir = debugfs_create_dir("nfsd", NULL);
137 if (!debug_dir)
138 goto fail;
139
140 for (i = 0; i < NUM_INJECT_OPS; i++) {
141 op = &inject_ops[i];
142 if (!debugfs_create_file(op->file, mode, debug_dir, op, &fops_nfsd))
143 goto fail;
144 }
145 return 0;
146
147 fail:
148 nfsd_fault_inject_cleanup();
149 return -ENOMEM;
150 }
151