diff options
author | Jeff Layton <jlayton@primarydata.com> | 2014-09-12 16:40:20 -0400 |
---|---|---|
committer | J. Bruce Fields <bfields@redhat.com> | 2014-09-17 16:33:11 -0400 |
commit | f7790029655f79cdcee4fa7c7884e0c2795ebebe (patch) | |
tree | 9181503273f1355a506a7658ec0115c20c2047d0 /fs/nfs_common | |
parent | f0c63124a6165792f6e37e4b5983792d009e1ce8 (diff) |
lockd: move lockd's grace period handling into its own module
Currently, all of the grace period handling is part of lockd. Eventually
though we'd like to be able to build v4-only servers, at which point
we'll need to put all of this elsewhere.
Move the code itself into fs/nfs_common and have it build a grace.ko
module. Then, rejigger the Kconfig options so that both nfsd and lockd
enable it automatically.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Diffstat (limited to 'fs/nfs_common')
-rw-r--r-- | fs/nfs_common/Makefile | 3 | ||||
-rw-r--r-- | fs/nfs_common/grace.c | 113 |
2 files changed, 115 insertions, 1 deletions
diff --git a/fs/nfs_common/Makefile b/fs/nfs_common/Makefile index f689ed82af3a..d153ca3ea577 100644 --- a/fs/nfs_common/Makefile +++ b/fs/nfs_common/Makefile | |||
@@ -3,5 +3,6 @@ | |||
3 | # | 3 | # |
4 | 4 | ||
5 | obj-$(CONFIG_NFS_ACL_SUPPORT) += nfs_acl.o | 5 | obj-$(CONFIG_NFS_ACL_SUPPORT) += nfs_acl.o |
6 | |||
7 | nfs_acl-objs := nfsacl.o | 6 | nfs_acl-objs := nfsacl.o |
7 | |||
8 | obj-$(CONFIG_GRACE_PERIOD) += grace.o | ||
diff --git a/fs/nfs_common/grace.c b/fs/nfs_common/grace.c new file mode 100644 index 000000000000..ae6e58ea4de5 --- /dev/null +++ b/fs/nfs_common/grace.c | |||
@@ -0,0 +1,113 @@ | |||
1 | /* | ||
2 | * Common code for control of lockd and nfsv4 grace periods. | ||
3 | * | ||
4 | * Transplanted from lockd code | ||
5 | */ | ||
6 | |||
7 | #include <linux/module.h> | ||
8 | #include <net/net_namespace.h> | ||
9 | #include <net/netns/generic.h> | ||
10 | #include <linux/fs.h> | ||
11 | |||
12 | static int grace_net_id; | ||
13 | static DEFINE_SPINLOCK(grace_lock); | ||
14 | |||
15 | /** | ||
16 | * locks_start_grace | ||
17 | * @net: net namespace that this lock manager belongs to | ||
18 | * @lm: who this grace period is for | ||
19 | * | ||
20 | * A grace period is a period during which locks should not be given | ||
21 | * out. Currently grace periods are only enforced by the two lock | ||
22 | * managers (lockd and nfsd), using the locks_in_grace() function to | ||
23 | * check when they are in a grace period. | ||
24 | * | ||
25 | * This function is called to start a grace period. | ||
26 | */ | ||
27 | void | ||
28 | locks_start_grace(struct net *net, struct lock_manager *lm) | ||
29 | { | ||
30 | struct list_head *grace_list = net_generic(net, grace_net_id); | ||
31 | |||
32 | spin_lock(&grace_lock); | ||
33 | list_add(&lm->list, grace_list); | ||
34 | spin_unlock(&grace_lock); | ||
35 | } | ||
36 | EXPORT_SYMBOL_GPL(locks_start_grace); | ||
37 | |||
38 | /** | ||
39 | * locks_end_grace | ||
40 | * @net: net namespace that this lock manager belongs to | ||
41 | * @lm: who this grace period is for | ||
42 | * | ||
43 | * Call this function to state that the given lock manager is ready to | ||
44 | * resume regular locking. The grace period will not end until all lock | ||
45 | * managers that called locks_start_grace() also call locks_end_grace(). | ||
46 | * Note that callers count on it being safe to call this more than once, | ||
47 | * and the second call should be a no-op. | ||
48 | */ | ||
49 | void | ||
50 | locks_end_grace(struct lock_manager *lm) | ||
51 | { | ||
52 | spin_lock(&grace_lock); | ||
53 | list_del_init(&lm->list); | ||
54 | spin_unlock(&grace_lock); | ||
55 | } | ||
56 | EXPORT_SYMBOL_GPL(locks_end_grace); | ||
57 | |||
58 | /** | ||
59 | * locks_in_grace | ||
60 | * | ||
61 | * Lock managers call this function to determine when it is OK for them | ||
62 | * to answer ordinary lock requests, and when they should accept only | ||
63 | * lock reclaims. | ||
64 | */ | ||
65 | int | ||
66 | locks_in_grace(struct net *net) | ||
67 | { | ||
68 | struct list_head *grace_list = net_generic(net, grace_net_id); | ||
69 | |||
70 | return !list_empty(grace_list); | ||
71 | } | ||
72 | EXPORT_SYMBOL_GPL(locks_in_grace); | ||
73 | |||
74 | static int __net_init | ||
75 | grace_init_net(struct net *net) | ||
76 | { | ||
77 | struct list_head *grace_list = net_generic(net, grace_net_id); | ||
78 | |||
79 | INIT_LIST_HEAD(grace_list); | ||
80 | return 0; | ||
81 | } | ||
82 | |||
83 | static void __net_exit | ||
84 | grace_exit_net(struct net *net) | ||
85 | { | ||
86 | struct list_head *grace_list = net_generic(net, grace_net_id); | ||
87 | |||
88 | BUG_ON(!list_empty(grace_list)); | ||
89 | } | ||
90 | |||
91 | static struct pernet_operations grace_net_ops = { | ||
92 | .init = grace_init_net, | ||
93 | .exit = grace_exit_net, | ||
94 | .id = &grace_net_id, | ||
95 | .size = sizeof(struct list_head), | ||
96 | }; | ||
97 | |||
98 | static int __init | ||
99 | init_grace(void) | ||
100 | { | ||
101 | return register_pernet_subsys(&grace_net_ops); | ||
102 | } | ||
103 | |||
104 | static void __exit | ||
105 | exit_grace(void) | ||
106 | { | ||
107 | unregister_pernet_subsys(&grace_net_ops); | ||
108 | } | ||
109 | |||
110 | MODULE_AUTHOR("Jeff Layton <jlayton@primarydata.com>"); | ||
111 | MODULE_LICENSE("GPL"); | ||
112 | module_init(init_grace) | ||
113 | module_exit(exit_grace) | ||