1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * Procfs support for lockd |
4 | * |
5 | * Copyright (c) 2014 Jeff Layton <jlayton@primarydata.com> |
6 | */ |
7 | |
8 | #include <linux/fs.h> |
9 | #include <linux/proc_fs.h> |
10 | #include <linux/module.h> |
11 | #include <linux/nsproxy.h> |
12 | #include <net/net_namespace.h> |
13 | |
14 | #include "netns.h" |
15 | #include "procfs.h" |
16 | |
17 | /* |
18 | * We only allow strings that start with 'Y', 'y', or '1'. |
19 | */ |
20 | static ssize_t |
21 | nlm_end_grace_write(struct file *file, const char __user *buf, size_t size, |
22 | loff_t *pos) |
23 | { |
24 | char *data; |
25 | struct lockd_net *ln = net_generic(current->nsproxy->net_ns, |
26 | id: lockd_net_id); |
27 | |
28 | if (size < 1) |
29 | return -EINVAL; |
30 | |
31 | data = simple_transaction_get(file, buf, size); |
32 | if (IS_ERR(ptr: data)) |
33 | return PTR_ERR(ptr: data); |
34 | |
35 | switch(data[0]) { |
36 | case 'Y': |
37 | case 'y': |
38 | case '1': |
39 | locks_end_grace(&ln->lockd_manager); |
40 | break; |
41 | default: |
42 | return -EINVAL; |
43 | } |
44 | |
45 | return size; |
46 | } |
47 | |
48 | static ssize_t |
49 | nlm_end_grace_read(struct file *file, char __user *buf, size_t size, |
50 | loff_t *pos) |
51 | { |
52 | struct lockd_net *ln = net_generic(current->nsproxy->net_ns, |
53 | id: lockd_net_id); |
54 | char resp[3]; |
55 | |
56 | resp[0] = list_empty(head: &ln->lockd_manager.list) ? 'Y' : 'N'; |
57 | resp[1] = '\n'; |
58 | resp[2] = '\0'; |
59 | |
60 | return simple_read_from_buffer(to: buf, count: size, ppos: pos, from: resp, available: sizeof(resp)); |
61 | } |
62 | |
63 | static const struct proc_ops lockd_end_grace_proc_ops = { |
64 | .proc_write = nlm_end_grace_write, |
65 | .proc_read = nlm_end_grace_read, |
66 | .proc_lseek = default_llseek, |
67 | .proc_release = simple_transaction_release, |
68 | }; |
69 | |
70 | int __init |
71 | lockd_create_procfs(void) |
72 | { |
73 | struct proc_dir_entry *entry; |
74 | |
75 | entry = proc_mkdir("fs/lockd" , NULL); |
76 | if (!entry) |
77 | return -ENOMEM; |
78 | entry = proc_create(name: "nlm_end_grace" , S_IRUGO|S_IWUSR, parent: entry, |
79 | proc_ops: &lockd_end_grace_proc_ops); |
80 | if (!entry) { |
81 | remove_proc_entry("fs/lockd" , NULL); |
82 | return -ENOMEM; |
83 | } |
84 | return 0; |
85 | } |
86 | |
87 | void __exit |
88 | lockd_remove_procfs(void) |
89 | { |
90 | remove_proc_entry("fs/lockd/nlm_end_grace" , NULL); |
91 | remove_proc_entry("fs/lockd" , NULL); |
92 | } |
93 | |