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 (*forget)(struct nfs4_client *, u64);
21 u64 (*print)(struct nfs4_client *, u64);
22 };
23
24 static struct nfsd_fault_inject_op inject_ops[] = {
25 {
26 .file = "forget_clients",
27 .forget = nfsd_forget_client,
28 .print = nfsd_print_client,
29 },
30 {
31 .file = "forget_locks",
32 .forget = nfsd_forget_client_locks,
33 .print = nfsd_print_client_locks,
34 },
35 {
36 .file = "forget_openowners",
37 .forget = nfsd_forget_client_openowners,
38 .print = nfsd_print_client_openowners,
39 },
40 {
41 .file = "forget_delegations",
42 .forget = nfsd_forget_client_delegations,
43 .print = nfsd_print_client_delegations,
44 },
45 {
46 .file = "recall_delegations",
47 .forget = nfsd_recall_client_delegations,
48 .print = nfsd_print_client_delegations,
49 },
50 };
51
52 static long int NUM_INJECT_OPS = sizeof(inject_ops) / sizeof(struct nfsd_fault_inject_op);
53 static struct dentry *debug_dir;
54
nfsd_inject_set(struct nfsd_fault_inject_op * op,u64 val)55 static void nfsd_inject_set(struct nfsd_fault_inject_op *op, u64 val)
56 {
57 u64 count = 0;
58
59 if (val == 0)
60 printk(KERN_INFO "NFSD Fault Injection: %s (all)", op->file);
61 else
62 printk(KERN_INFO "NFSD Fault Injection: %s (n = %llu)", op->file, val);
63
64 nfs4_lock_state();
65 count = nfsd_for_n_state(val, op->forget);
66 nfs4_unlock_state();
67 printk(KERN_INFO "NFSD: %s: found %llu", op->file, count);
68 }
69
nfsd_inject_set_client(struct nfsd_fault_inject_op * op,struct sockaddr_storage * addr,size_t addr_size)70 static void nfsd_inject_set_client(struct nfsd_fault_inject_op *op,
71 struct sockaddr_storage *addr,
72 size_t addr_size)
73 {
74 char buf[INET6_ADDRSTRLEN];
75 struct nfs4_client *clp;
76 u64 count;
77
78 nfs4_lock_state();
79 clp = nfsd_find_client(addr, addr_size);
80 if (clp) {
81 count = op->forget(clp, 0);
82 rpc_ntop((struct sockaddr *)&clp->cl_addr, buf, sizeof(buf));
83 printk(KERN_INFO "NFSD [%s]: Client %s had %llu state object(s)\n", op->file, buf, count);
84 }
85 nfs4_unlock_state();
86 }
87
nfsd_inject_get(struct nfsd_fault_inject_op * op,u64 * val)88 static void nfsd_inject_get(struct nfsd_fault_inject_op *op, u64 *val)
89 {
90 nfs4_lock_state();
91 *val = nfsd_for_n_state(0, op->print);
92 nfs4_unlock_state();
93 }
94
fault_inject_read(struct file * file,char __user * buf,size_t len,loff_t * ppos)95 static ssize_t fault_inject_read(struct file *file, char __user *buf,
96 size_t len, loff_t *ppos)
97 {
98 static u64 val;
99 char read_buf[25];
100 size_t size, ret;
101 loff_t pos = *ppos;
102
103 if (!pos)
104 nfsd_inject_get(file_inode(file)->i_private, &val);
105 size = scnprintf(read_buf, sizeof(read_buf), "%llu\n", val);
106
107 if (pos < 0)
108 return -EINVAL;
109 if (pos >= size || !len)
110 return 0;
111 if (len > size - pos)
112 len = size - pos;
113 ret = copy_to_user(buf, read_buf + pos, len);
114 if (ret == len)
115 return -EFAULT;
116 len -= ret;
117 *ppos = pos + len;
118 return len;
119 }
120
fault_inject_write(struct file * file,const char __user * buf,size_t len,loff_t * ppos)121 static ssize_t fault_inject_write(struct file *file, const char __user *buf,
122 size_t len, loff_t *ppos)
123 {
124 char write_buf[INET6_ADDRSTRLEN];
125 size_t size = min(sizeof(write_buf) - 1, len);
126 struct net *net = current->nsproxy->net_ns;
127 struct sockaddr_storage sa;
128 u64 val;
129
130 if (copy_from_user(write_buf, buf, size))
131 return -EFAULT;
132 write_buf[size] = '\0';
133
134 size = rpc_pton(net, write_buf, size, (struct sockaddr *)&sa, sizeof(sa));
135 if (size > 0)
136 nfsd_inject_set_client(file_inode(file)->i_private, &sa, size);
137 else {
138 val = simple_strtoll(write_buf, NULL, 0);
139 nfsd_inject_set(file_inode(file)->i_private, val);
140 }
141 return len; /* on success, claim we got the whole input */
142 }
143
144 static const struct file_operations fops_nfsd = {
145 .owner = THIS_MODULE,
146 .read = fault_inject_read,
147 .write = fault_inject_write,
148 };
149
nfsd_fault_inject_cleanup(void)150 void nfsd_fault_inject_cleanup(void)
151 {
152 debugfs_remove_recursive(debug_dir);
153 }
154
nfsd_fault_inject_init(void)155 int nfsd_fault_inject_init(void)
156 {
157 unsigned int i;
158 struct nfsd_fault_inject_op *op;
159 umode_t mode = S_IFREG | S_IRUSR | S_IWUSR;
160
161 debug_dir = debugfs_create_dir("nfsd", NULL);
162 if (!debug_dir)
163 goto fail;
164
165 for (i = 0; i < NUM_INJECT_OPS; i++) {
166 op = &inject_ops[i];
167 if (!debugfs_create_file(op->file, mode, debug_dir, op, &fops_nfsd))
168 goto fail;
169 }
170 return 0;
171
172 fail:
173 nfsd_fault_inject_cleanup();
174 return -ENOMEM;
175 }
176