coredump: remove redundant defines for dumpable states
[linux-3.10.git] / fs / autofs4 / inode.c
1 /* -*- c -*- --------------------------------------------------------------- *
2  *
3  * linux/fs/autofs/inode.c
4  *
5  *  Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved
6  *  Copyright 2005-2006 Ian Kent <raven@themaw.net>
7  *
8  * This file is part of the Linux kernel and is made available under
9  * the terms of the GNU General Public License, version 2, or at your
10  * option, any later version, incorporated herein by reference.
11  *
12  * ------------------------------------------------------------------------- */
13
14 #include <linux/kernel.h>
15 #include <linux/slab.h>
16 #include <linux/file.h>
17 #include <linux/seq_file.h>
18 #include <linux/pagemap.h>
19 #include <linux/parser.h>
20 #include <linux/bitops.h>
21 #include <linux/magic.h>
22 #include "autofs_i.h"
23 #include <linux/module.h>
24
25 struct autofs_info *autofs4_new_ino(struct autofs_sb_info *sbi)
26 {
27         struct autofs_info *ino = kzalloc(sizeof(*ino), GFP_KERNEL);
28         if (ino) {
29                 INIT_LIST_HEAD(&ino->active);
30                 INIT_LIST_HEAD(&ino->expiring);
31                 ino->last_used = jiffies;
32                 ino->sbi = sbi;
33         }
34         return ino;
35 }
36
37 void autofs4_clean_ino(struct autofs_info *ino)
38 {
39         ino->uid = GLOBAL_ROOT_UID;
40         ino->gid = GLOBAL_ROOT_GID;
41         ino->last_used = jiffies;
42 }
43
44 void autofs4_free_ino(struct autofs_info *ino)
45 {
46         kfree(ino);
47 }
48
49 void autofs4_kill_sb(struct super_block *sb)
50 {
51         struct autofs_sb_info *sbi = autofs4_sbi(sb);
52
53         /*
54          * In the event of a failure in get_sb_nodev the superblock
55          * info is not present so nothing else has been setup, so
56          * just call kill_anon_super when we are called from
57          * deactivate_super.
58          */
59         if (!sbi)
60                 goto out_kill_sb;
61
62         /* Free wait queues, close pipe */
63         autofs4_catatonic_mode(sbi);
64
65         sb->s_fs_info = NULL;
66         kfree(sbi);
67
68 out_kill_sb:
69         DPRINTK("shutting down");
70         kill_litter_super(sb);
71 }
72
73 static int autofs4_show_options(struct seq_file *m, struct dentry *root)
74 {
75         struct autofs_sb_info *sbi = autofs4_sbi(root->d_sb);
76         struct inode *root_inode = root->d_sb->s_root->d_inode;
77
78         if (!sbi)
79                 return 0;
80
81         seq_printf(m, ",fd=%d", sbi->pipefd);
82         if (!uid_eq(root_inode->i_uid, GLOBAL_ROOT_UID))
83                 seq_printf(m, ",uid=%u",
84                         from_kuid_munged(&init_user_ns, root_inode->i_uid));
85         if (!gid_eq(root_inode->i_gid, GLOBAL_ROOT_GID))
86                 seq_printf(m, ",gid=%u",
87                         from_kgid_munged(&init_user_ns, root_inode->i_gid));
88         seq_printf(m, ",pgrp=%d", sbi->oz_pgrp);
89         seq_printf(m, ",timeout=%lu", sbi->exp_timeout/HZ);
90         seq_printf(m, ",minproto=%d", sbi->min_proto);
91         seq_printf(m, ",maxproto=%d", sbi->max_proto);
92
93         if (autofs_type_offset(sbi->type))
94                 seq_printf(m, ",offset");
95         else if (autofs_type_direct(sbi->type))
96                 seq_printf(m, ",direct");
97         else
98                 seq_printf(m, ",indirect");
99
100         return 0;
101 }
102
103 static void autofs4_evict_inode(struct inode *inode)
104 {
105         clear_inode(inode);
106         kfree(inode->i_private);
107 }
108
109 static const struct super_operations autofs4_sops = {
110         .statfs         = simple_statfs,
111         .show_options   = autofs4_show_options,
112         .evict_inode    = autofs4_evict_inode,
113 };
114
115 enum {Opt_err, Opt_fd, Opt_uid, Opt_gid, Opt_pgrp, Opt_minproto, Opt_maxproto,
116         Opt_indirect, Opt_direct, Opt_offset};
117
118 static const match_table_t tokens = {
119         {Opt_fd, "fd=%u"},
120         {Opt_uid, "uid=%u"},
121         {Opt_gid, "gid=%u"},
122         {Opt_pgrp, "pgrp=%u"},
123         {Opt_minproto, "minproto=%u"},
124         {Opt_maxproto, "maxproto=%u"},
125         {Opt_indirect, "indirect"},
126         {Opt_direct, "direct"},
127         {Opt_offset, "offset"},
128         {Opt_err, NULL}
129 };
130
131 static int parse_options(char *options, int *pipefd, kuid_t *uid, kgid_t *gid,
132                 pid_t *pgrp, unsigned int *type, int *minproto, int *maxproto)
133 {
134         char *p;
135         substring_t args[MAX_OPT_ARGS];
136         int option;
137
138         *uid = current_uid();
139         *gid = current_gid();
140         *pgrp = task_pgrp_nr(current);
141
142         *minproto = AUTOFS_MIN_PROTO_VERSION;
143         *maxproto = AUTOFS_MAX_PROTO_VERSION;
144
145         *pipefd = -1;
146
147         if (!options)
148                 return 1;
149
150         while ((p = strsep(&options, ",")) != NULL) {
151                 int token;
152                 if (!*p)
153                         continue;
154
155                 token = match_token(p, tokens, args);
156                 switch (token) {
157                 case Opt_fd:
158                         if (match_int(args, pipefd))
159                                 return 1;
160                         break;
161                 case Opt_uid:
162                         if (match_int(args, &option))
163                                 return 1;
164                         *uid = make_kuid(current_user_ns(), option);
165                         if (!uid_valid(*uid))
166                                 return 1;
167                         break;
168                 case Opt_gid:
169                         if (match_int(args, &option))
170                                 return 1;
171                         *gid = make_kgid(current_user_ns(), option);
172                         if (!gid_valid(*gid))
173                                 return 1;
174                         break;
175                 case Opt_pgrp:
176                         if (match_int(args, &option))
177                                 return 1;
178                         *pgrp = option;
179                         break;
180                 case Opt_minproto:
181                         if (match_int(args, &option))
182                                 return 1;
183                         *minproto = option;
184                         break;
185                 case Opt_maxproto:
186                         if (match_int(args, &option))
187                                 return 1;
188                         *maxproto = option;
189                         break;
190                 case Opt_indirect:
191                         set_autofs_type_indirect(type);
192                         break;
193                 case Opt_direct:
194                         set_autofs_type_direct(type);
195                         break;
196                 case Opt_offset:
197                         set_autofs_type_offset(type);
198                         break;
199                 default:
200                         return 1;
201                 }
202         }
203         return (*pipefd < 0);
204 }
205
206 int autofs4_fill_super(struct super_block *s, void *data, int silent)
207 {
208         struct inode * root_inode;
209         struct dentry * root;
210         struct file * pipe;
211         int pipefd;
212         struct autofs_sb_info *sbi;
213         struct autofs_info *ino;
214
215         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
216         if (!sbi)
217                 goto fail_unlock;
218         DPRINTK("starting up, sbi = %p",sbi);
219
220         s->s_fs_info = sbi;
221         sbi->magic = AUTOFS_SBI_MAGIC;
222         sbi->pipefd = -1;
223         sbi->pipe = NULL;
224         sbi->catatonic = 1;
225         sbi->exp_timeout = 0;
226         sbi->oz_pgrp = task_pgrp_nr(current);
227         sbi->sb = s;
228         sbi->version = 0;
229         sbi->sub_version = 0;
230         set_autofs_type_indirect(&sbi->type);
231         sbi->min_proto = 0;
232         sbi->max_proto = 0;
233         mutex_init(&sbi->wq_mutex);
234         mutex_init(&sbi->pipe_mutex);
235         spin_lock_init(&sbi->fs_lock);
236         sbi->queues = NULL;
237         spin_lock_init(&sbi->lookup_lock);
238         INIT_LIST_HEAD(&sbi->active_list);
239         INIT_LIST_HEAD(&sbi->expiring_list);
240         s->s_blocksize = 1024;
241         s->s_blocksize_bits = 10;
242         s->s_magic = AUTOFS_SUPER_MAGIC;
243         s->s_op = &autofs4_sops;
244         s->s_d_op = &autofs4_dentry_operations;
245         s->s_time_gran = 1;
246
247         /*
248          * Get the root inode and dentry, but defer checking for errors.
249          */
250         ino = autofs4_new_ino(sbi);
251         if (!ino)
252                 goto fail_free;
253         root_inode = autofs4_get_inode(s, S_IFDIR | 0755);
254         root = d_make_root(root_inode);
255         if (!root)
256                 goto fail_ino;
257         pipe = NULL;
258
259         root->d_fsdata = ino;
260
261         /* Can this call block? */
262         if (parse_options(data, &pipefd, &root_inode->i_uid, &root_inode->i_gid,
263                                 &sbi->oz_pgrp, &sbi->type, &sbi->min_proto,
264                                 &sbi->max_proto)) {
265                 printk("autofs: called with bogus options\n");
266                 goto fail_dput;
267         }
268
269         if (autofs_type_trigger(sbi->type))
270                 __managed_dentry_set_managed(root);
271
272         root_inode->i_fop = &autofs4_root_operations;
273         root_inode->i_op = &autofs4_dir_inode_operations;
274
275         /* Couldn't this be tested earlier? */
276         if (sbi->max_proto < AUTOFS_MIN_PROTO_VERSION ||
277             sbi->min_proto > AUTOFS_MAX_PROTO_VERSION) {
278                 printk("autofs: kernel does not match daemon version "
279                        "daemon (%d, %d) kernel (%d, %d)\n",
280                         sbi->min_proto, sbi->max_proto,
281                         AUTOFS_MIN_PROTO_VERSION, AUTOFS_MAX_PROTO_VERSION);
282                 goto fail_dput;
283         }
284
285         /* Establish highest kernel protocol version */
286         if (sbi->max_proto > AUTOFS_MAX_PROTO_VERSION)
287                 sbi->version = AUTOFS_MAX_PROTO_VERSION;
288         else
289                 sbi->version = sbi->max_proto;
290         sbi->sub_version = AUTOFS_PROTO_SUBVERSION;
291
292         DPRINTK("pipe fd = %d, pgrp = %u", pipefd, sbi->oz_pgrp);
293         pipe = fget(pipefd);
294         
295         if (!pipe) {
296                 printk("autofs: could not open pipe file descriptor\n");
297                 goto fail_dput;
298         }
299         if (autofs_prepare_pipe(pipe) < 0)
300                 goto fail_fput;
301         sbi->pipe = pipe;
302         sbi->pipefd = pipefd;
303         sbi->catatonic = 0;
304
305         /*
306          * Success! Install the root dentry now to indicate completion.
307          */
308         s->s_root = root;
309         return 0;
310         
311         /*
312          * Failure ... clean up.
313          */
314 fail_fput:
315         printk("autofs: pipe file descriptor does not contain proper ops\n");
316         fput(pipe);
317         /* fall through */
318 fail_dput:
319         dput(root);
320         goto fail_free;
321 fail_ino:
322         kfree(ino);
323 fail_free:
324         kfree(sbi);
325         s->s_fs_info = NULL;
326 fail_unlock:
327         return -EINVAL;
328 }
329
330 struct inode *autofs4_get_inode(struct super_block *sb, umode_t mode)
331 {
332         struct inode *inode = new_inode(sb);
333
334         if (inode == NULL)
335                 return NULL;
336
337         inode->i_mode = mode;
338         if (sb->s_root) {
339                 inode->i_uid = sb->s_root->d_inode->i_uid;
340                 inode->i_gid = sb->s_root->d_inode->i_gid;
341         }
342         inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
343         inode->i_ino = get_next_ino();
344
345         if (S_ISDIR(mode)) {
346                 set_nlink(inode, 2);
347                 inode->i_op = &autofs4_dir_inode_operations;
348                 inode->i_fop = &autofs4_dir_operations;
349         } else if (S_ISLNK(mode)) {
350                 inode->i_op = &autofs4_symlink_inode_operations;
351         }
352
353         return inode;
354 }