[XFS] Fix race when looking up reclaimable inodes
[linux-2.6] / fs / gfs2 / mount.c
1 /*
2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
3  * Copyright (C) 2004-2006 Red Hat, Inc.  All rights reserved.
4  *
5  * This copyrighted material is made available to anyone wishing to use,
6  * modify, copy, or redistribute it subject to the terms and conditions
7  * of the GNU General Public License version 2.
8  */
9
10 #include <linux/slab.h>
11 #include <linux/spinlock.h>
12 #include <linux/completion.h>
13 #include <linux/buffer_head.h>
14 #include <linux/gfs2_ondisk.h>
15 #include <linux/lm_interface.h>
16 #include <linux/parser.h>
17
18 #include "gfs2.h"
19 #include "incore.h"
20 #include "mount.h"
21 #include "sys.h"
22 #include "util.h"
23
24 enum {
25         Opt_lockproto,
26         Opt_locktable,
27         Opt_hostdata,
28         Opt_spectator,
29         Opt_ignore_local_fs,
30         Opt_localflocks,
31         Opt_localcaching,
32         Opt_debug,
33         Opt_nodebug,
34         Opt_upgrade,
35         Opt_num_glockd,
36         Opt_acl,
37         Opt_noacl,
38         Opt_quota_off,
39         Opt_quota_account,
40         Opt_quota_on,
41         Opt_suiddir,
42         Opt_nosuiddir,
43         Opt_data_writeback,
44         Opt_data_ordered,
45         Opt_meta,
46         Opt_err,
47 };
48
49 static const match_table_t tokens = {
50         {Opt_lockproto, "lockproto=%s"},
51         {Opt_locktable, "locktable=%s"},
52         {Opt_hostdata, "hostdata=%s"},
53         {Opt_spectator, "spectator"},
54         {Opt_ignore_local_fs, "ignore_local_fs"},
55         {Opt_localflocks, "localflocks"},
56         {Opt_localcaching, "localcaching"},
57         {Opt_debug, "debug"},
58         {Opt_nodebug, "nodebug"},
59         {Opt_upgrade, "upgrade"},
60         {Opt_num_glockd, "num_glockd=%d"},
61         {Opt_acl, "acl"},
62         {Opt_noacl, "noacl"},
63         {Opt_quota_off, "quota=off"},
64         {Opt_quota_account, "quota=account"},
65         {Opt_quota_on, "quota=on"},
66         {Opt_suiddir, "suiddir"},
67         {Opt_nosuiddir, "nosuiddir"},
68         {Opt_data_writeback, "data=writeback"},
69         {Opt_data_ordered, "data=ordered"},
70         {Opt_meta, "meta"},
71         {Opt_err, NULL}
72 };
73
74 /**
75  * gfs2_mount_args - Parse mount options
76  * @sdp:
77  * @data:
78  *
79  * Return: errno
80  */
81
82 int gfs2_mount_args(struct gfs2_sbd *sdp, char *data_arg, int remount)
83 {
84         struct gfs2_args *args = &sdp->sd_args;
85         char *data = data_arg;
86         char *options, *o, *v;
87         int error = 0;
88
89         if (!remount) {
90                 /*  If someone preloaded options, use those instead  */
91                 spin_lock(&gfs2_sys_margs_lock);
92                 if (gfs2_sys_margs) {
93                         data = gfs2_sys_margs;
94                         gfs2_sys_margs = NULL;
95                 }
96                 spin_unlock(&gfs2_sys_margs_lock);
97
98                 /*  Set some defaults  */
99                 args->ar_num_glockd = GFS2_GLOCKD_DEFAULT;
100                 args->ar_quota = GFS2_QUOTA_DEFAULT;
101                 args->ar_data = GFS2_DATA_DEFAULT;
102         }
103
104         /* Split the options into tokens with the "," character and
105            process them */
106
107         for (options = data; (o = strsep(&options, ",")); ) {
108                 int token, option;
109                 substring_t tmp[MAX_OPT_ARGS];
110
111                 if (!*o)
112                         continue;
113
114                 token = match_token(o, tokens, tmp);
115                 switch (token) {
116                 case Opt_lockproto:
117                         v = match_strdup(&tmp[0]);
118                         if (!v) {
119                                 fs_info(sdp, "no memory for lockproto\n");
120                                 error = -ENOMEM;
121                                 goto out_error;
122                         }
123
124                         if (remount && strcmp(v, args->ar_lockproto)) {
125                                 kfree(v);
126                                 goto cant_remount;
127                         }
128                         
129                         strncpy(args->ar_lockproto, v, GFS2_LOCKNAME_LEN);
130                         args->ar_lockproto[GFS2_LOCKNAME_LEN - 1] = 0;
131                         kfree(v);
132                         break;
133                 case Opt_locktable:
134                         v = match_strdup(&tmp[0]);
135                         if (!v) {
136                                 fs_info(sdp, "no memory for locktable\n");
137                                 error = -ENOMEM;
138                                 goto out_error;
139                         }
140
141                         if (remount && strcmp(v, args->ar_locktable)) {
142                                 kfree(v);
143                                 goto cant_remount;
144                         }
145
146                         strncpy(args->ar_locktable, v, GFS2_LOCKNAME_LEN);
147                         args->ar_locktable[GFS2_LOCKNAME_LEN - 1]  = 0;
148                         kfree(v);
149                         break;
150                 case Opt_hostdata:
151                         v = match_strdup(&tmp[0]);
152                         if (!v) {
153                                 fs_info(sdp, "no memory for hostdata\n");
154                                 error = -ENOMEM;
155                                 goto out_error;
156                         }
157
158                         if (remount && strcmp(v, args->ar_hostdata)) {
159                                 kfree(v);
160                                 goto cant_remount;
161                         }
162
163                         strncpy(args->ar_hostdata, v, GFS2_LOCKNAME_LEN);
164                         args->ar_hostdata[GFS2_LOCKNAME_LEN - 1] = 0;
165                         kfree(v);
166                         break;
167                 case Opt_spectator:
168                         if (remount && !args->ar_spectator)
169                                 goto cant_remount;
170                         args->ar_spectator = 1;
171                         sdp->sd_vfs->s_flags |= MS_RDONLY;
172                         break;
173                 case Opt_ignore_local_fs:
174                         if (remount && !args->ar_ignore_local_fs)
175                                 goto cant_remount;
176                         args->ar_ignore_local_fs = 1;
177                         break;
178                 case Opt_localflocks:
179                         if (remount && !args->ar_localflocks)
180                                 goto cant_remount;
181                         args->ar_localflocks = 1;
182                         break;
183                 case Opt_localcaching:
184                         if (remount && !args->ar_localcaching)
185                                 goto cant_remount;
186                         args->ar_localcaching = 1;
187                         break;
188                 case Opt_debug:
189                         args->ar_debug = 1;
190                         break;
191                 case Opt_nodebug:
192                         args->ar_debug = 0;
193                         break;
194                 case Opt_upgrade:
195                         if (remount && !args->ar_upgrade)
196                                 goto cant_remount;
197                         args->ar_upgrade = 1;
198                         break;
199                 case Opt_num_glockd:
200                         if ((error = match_int(&tmp[0], &option))) {
201                                 fs_info(sdp, "problem getting num_glockd\n");
202                                 goto out_error;
203                         }
204
205                         if (remount && option != args->ar_num_glockd)
206                                 goto cant_remount;
207                         if (!option || option > GFS2_GLOCKD_MAX) {
208                                 fs_info(sdp, "0 < num_glockd <= %u  (not %u)\n",
209                                         GFS2_GLOCKD_MAX, option);
210                                 error = -EINVAL;
211                                 goto out_error;
212                         }
213                         args->ar_num_glockd = option;
214                         break;
215                 case Opt_acl:
216                         args->ar_posix_acl = 1;
217                         sdp->sd_vfs->s_flags |= MS_POSIXACL;
218                         break;
219                 case Opt_noacl:
220                         args->ar_posix_acl = 0;
221                         sdp->sd_vfs->s_flags &= ~MS_POSIXACL;
222                         break;
223                 case Opt_quota_off:
224                         args->ar_quota = GFS2_QUOTA_OFF;
225                         break;
226                 case Opt_quota_account:
227                         args->ar_quota = GFS2_QUOTA_ACCOUNT;
228                         break;
229                 case Opt_quota_on:
230                         args->ar_quota = GFS2_QUOTA_ON;
231                         break;
232                 case Opt_suiddir:
233                         args->ar_suiddir = 1;
234                         break;
235                 case Opt_nosuiddir:
236                         args->ar_suiddir = 0;
237                         break;
238                 case Opt_data_writeback:
239                         args->ar_data = GFS2_DATA_WRITEBACK;
240                         break;
241                 case Opt_data_ordered:
242                         args->ar_data = GFS2_DATA_ORDERED;
243                         break;
244                 case Opt_meta:
245                         if (remount && args->ar_meta != 1)
246                                 goto cant_remount;
247                         args->ar_meta = 1;
248                         break;
249                 case Opt_err:
250                 default:
251                         fs_info(sdp, "unknown option: %s\n", o);
252                         error = -EINVAL;
253                         goto out_error;
254                 }
255         }
256
257 out_error:
258         if (error)
259                 fs_info(sdp, "invalid mount option(s)\n");
260
261         if (data != data_arg)
262                 kfree(data);
263
264         return error;
265
266 cant_remount:
267         fs_info(sdp, "can't remount with option %s\n", o);
268         return -EINVAL;
269 }
270