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LU-7898 osd: remove unnecessary declarations
[fs/lustre-release.git] / lustre / obdclass / idmap.c
1 /*
2  * GPL HEADER START
3  *
4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 only,
8  * as published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it will be useful, but
11  * WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13  * General Public License version 2 for more details (a copy is included
14  * in the LICENSE file that accompanied this code).
15  *
16  * You should have received a copy of the GNU General Public License
17  * version 2 along with this program; If not, see
18  * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
19  *
20  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
21  * CA 95054 USA or visit www.sun.com if you need additional information or
22  * have any questions.
23  *
24  * GPL HEADER END
25  */
26 /*
27  * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
28  * Use is subject to license terms.
29  *
30  * Copyright (c) 2012, 2014, Intel Corporation.
31  */
32 /*
33  * This file is part of Lustre, http://www.lustre.org/
34  * Lustre is a trademark of Sun Microsystems, Inc.
35  *
36  * lustre/obdclass/idmap.c
37  *
38  * Lustre user identity mapping.
39  *
40  * Author: Fan Yong <fanyong@clusterfs.com>
41  */
42
43 #define DEBUG_SUBSYSTEM S_SEC
44
45 #include <linux/user_namespace.h>
46 #ifdef HAVE_UIDGID_HEADER
47 # include <linux/uidgid.h>
48 #endif
49 #include <lustre_idmap.h>
50 #include <upcall_cache.h>
51 #include <md_object.h>
52 #include <obd_support.h>
53
54 #define lustre_get_group_info(group_info) do {          \
55         atomic_inc(&(group_info)->usage);               \
56 } while (0)
57
58 #define lustre_put_group_info(group_info) do {          \
59         if (atomic_dec_and_test(&(group_info)->usage))  \
60                 groups_free(group_info);                \
61 } while (0)
62
63 /*
64  * groups_search() is copied from linux kernel!
65  * A simple bsearch.
66  */
67 static int lustre_groups_search(struct group_info *group_info,
68                                 gid_t grp)
69 {
70         int left, right;
71
72         if (!group_info)
73                 return 0;
74
75         left = 0;
76         right = group_info->ngroups;
77         while (left < right) {
78                 int mid = (left + right) / 2;
79                 int cmp = grp -
80                         from_kgid(&init_user_ns, CFS_GROUP_AT(group_info, mid));
81
82                 if (cmp > 0)
83                         left = mid + 1;
84                 else if (cmp < 0)
85                         right = mid;
86                 else
87                         return 1;
88         }
89         return 0;
90 }
91
92 void lustre_groups_from_list(struct group_info *ginfo, gid_t *glist)
93 {
94         int i;
95         int count = ginfo->ngroups;
96
97         /* fill group_info from gid array */
98         for (i = 0; i < ginfo->nblocks && count > 0; i++) {
99                 int cp_count = min(CFS_NGROUPS_PER_BLOCK, count);
100                 int off = i * CFS_NGROUPS_PER_BLOCK;
101                 int len = cp_count * sizeof(*glist);
102
103                 memcpy(ginfo->blocks[i], glist + off, len);
104                 count -= cp_count;
105         }
106 }
107 EXPORT_SYMBOL(lustre_groups_from_list);
108
109 /* groups_sort() is copied from linux kernel! */
110 /* a simple shell-metzner sort */
111 void lustre_groups_sort(struct group_info *group_info)
112 {
113         int base, max, stride;
114         int gidsetsize = group_info->ngroups;
115
116         for (stride = 1; stride < gidsetsize; stride = 3 * stride + 1)
117                 ; /* nothing */
118         stride /= 3;
119
120         while (stride) {
121                 max = gidsetsize - stride;
122                 for (base = 0; base < max; base++) {
123                         int left = base;
124                         int right = left + stride;
125                         gid_t tmp = from_kgid(&init_user_ns,
126                                               CFS_GROUP_AT(group_info, right));
127
128                         while (left >= 0 &&
129                                tmp < from_kgid(&init_user_ns,
130                                                CFS_GROUP_AT(group_info, left))) {
131                                 CFS_GROUP_AT(group_info, right) =
132                                         CFS_GROUP_AT(group_info, left);
133                                 right = left;
134                                 left -= stride;
135                         }
136                         CFS_GROUP_AT(group_info, right) =
137                                                 make_kgid(&init_user_ns, tmp);
138                 }
139                 stride /= 3;
140         }
141 }
142 EXPORT_SYMBOL(lustre_groups_sort);
143
144 int lustre_in_group_p(struct lu_ucred *mu, gid_t grp)
145 {
146         int rc = 1;
147
148         if (grp != mu->uc_fsgid) {
149                 struct group_info *group_info = NULL;
150
151                 if (mu->uc_ginfo || !mu->uc_identity ||
152                     mu->uc_valid == UCRED_OLD)
153                         if (grp == mu->uc_suppgids[0] ||
154                             grp == mu->uc_suppgids[1])
155                                 return 1;
156
157                 if (mu->uc_ginfo)
158                         group_info = mu->uc_ginfo;
159                 else if (mu->uc_identity)
160                         group_info = mu->uc_identity->mi_ginfo;
161
162                 if (!group_info)
163                         return 0;
164
165                 lustre_get_group_info(group_info);
166                 rc = lustre_groups_search(group_info, grp);
167                 lustre_put_group_info(group_info);
168         }
169         return rc;
170 }
171 EXPORT_SYMBOL(lustre_in_group_p);