[PATCH] knfsd: when looking up a lockd host, pass hostname & length
[linux-2.6.git] / fs / lockd / svcshare.c
1 /*
2  * linux/fs/lockd/svcshare.c
3  *
4  * Management of DOS shares.
5  *
6  * Copyright (C) 1996 Olaf Kirch <okir@monad.swb.de>
7  */
8
9 #include <linux/time.h>
10 #include <linux/unistd.h>
11 #include <linux/string.h>
12 #include <linux/slab.h>
13
14 #include <linux/sunrpc/clnt.h>
15 #include <linux/sunrpc/svc.h>
16 #include <linux/lockd/lockd.h>
17 #include <linux/lockd/share.h>
18
19 static inline int
20 nlm_cmp_owner(struct nlm_share *share, struct xdr_netobj *oh)
21 {
22         return share->s_owner.len == oh->len
23             && !memcmp(share->s_owner.data, oh->data, oh->len);
24 }
25
26 u32
27 nlmsvc_share_file(struct nlm_host *host, struct nlm_file *file,
28                         struct nlm_args *argp)
29 {
30         struct nlm_share        *share;
31         struct xdr_netobj       *oh = &argp->lock.oh;
32         u8                      *ohdata;
33
34         for (share = file->f_shares; share; share = share->s_next) {
35                 if (share->s_host == host && nlm_cmp_owner(share, oh))
36                         goto update;
37                 if ((argp->fsm_access & share->s_mode)
38                  || (argp->fsm_mode   & share->s_access ))
39                         return nlm_lck_denied;
40         }
41
42         share = (struct nlm_share *) kmalloc(sizeof(*share) + oh->len,
43                                                 GFP_KERNEL);
44         if (share == NULL)
45                 return nlm_lck_denied_nolocks;
46
47         /* Copy owner handle */
48         ohdata = (u8 *) (share + 1);
49         memcpy(ohdata, oh->data, oh->len);
50
51         share->s_file       = file;
52         share->s_host       = host;
53         share->s_owner.data = ohdata;
54         share->s_owner.len  = oh->len;
55         share->s_next       = file->f_shares;
56         file->f_shares      = share;
57
58 update:
59         share->s_access = argp->fsm_access;
60         share->s_mode   = argp->fsm_mode;
61         return nlm_granted;
62 }
63
64 /*
65  * Delete a share.
66  */
67 u32
68 nlmsvc_unshare_file(struct nlm_host *host, struct nlm_file *file,
69                         struct nlm_args *argp)
70 {
71         struct nlm_share        *share, **shpp;
72         struct xdr_netobj       *oh = &argp->lock.oh;
73
74         for (shpp = &file->f_shares; (share = *shpp) != 0; shpp = &share->s_next) {
75                 if (share->s_host == host && nlm_cmp_owner(share, oh)) {
76                         *shpp = share->s_next;
77                         kfree(share);
78                         return nlm_granted;
79                 }
80         }
81
82         /* X/Open spec says return success even if there was no
83          * corresponding share. */
84         return nlm_granted;
85 }
86
87 /*
88  * Traverse all shares for a given file (and host).
89  * NLM_ACT_CHECK is handled by nlmsvc_inspect_file.
90  */
91 void
92 nlmsvc_traverse_shares(struct nlm_host *host, struct nlm_file *file, int action)
93 {
94         struct nlm_share        *share, **shpp;
95
96         shpp = &file->f_shares;
97         while ((share = *shpp) !=  NULL) {
98                 if (action == NLM_ACT_MARK)
99                         share->s_host->h_inuse = 1;
100                 else if (action == NLM_ACT_UNLOCK) {
101                         if (host == NULL || host == share->s_host) {
102                                 *shpp = share->s_next;
103                                 kfree(share);
104                                 continue;
105                         }
106                 }
107                 shpp = &share->s_next;
108         }
109 }