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13#include <linux/kernel.h>
14#include <linux/mm.h>
15#include <linux/slab.h>
16#include <linux/file.h>
17#include <linux/parser.h>
18#include <linux/bitops.h>
19#include <linux/magic.h>
20#include "autofs_i.h"
21#include <linux/module.h>
22
23void autofs_kill_sb(struct super_block *sb)
24{
25 struct autofs_sb_info *sbi = autofs_sbi(sb);
26 unsigned int n;
27
28
29
30
31
32
33
34 if (!sbi)
35 goto out_kill_sb;
36
37 if (!sbi->catatonic)
38 autofs_catatonic_mode(sbi);
39
40 put_pid(sbi->oz_pgrp);
41
42 autofs_hash_nuke(sbi);
43 for (n = 0; n < AUTOFS_MAX_SYMLINKS; n++) {
44 if (test_bit(n, sbi->symlink_bitmap))
45 kfree(sbi->symlink[n].data);
46 }
47
48 kfree(sb->s_fs_info);
49
50out_kill_sb:
51 DPRINTK(("autofs: shutting down\n"));
52 kill_anon_super(sb);
53}
54
55static const struct super_operations autofs_sops = {
56 .statfs = simple_statfs,
57 .show_options = generic_show_options,
58};
59
60enum {Opt_err, Opt_fd, Opt_uid, Opt_gid, Opt_pgrp, Opt_minproto, Opt_maxproto};
61
62static const match_table_t autofs_tokens = {
63 {Opt_fd, "fd=%u"},
64 {Opt_uid, "uid=%u"},
65 {Opt_gid, "gid=%u"},
66 {Opt_pgrp, "pgrp=%u"},
67 {Opt_minproto, "minproto=%u"},
68 {Opt_maxproto, "maxproto=%u"},
69 {Opt_err, NULL}
70};
71
72static int parse_options(char *options, int *pipefd, uid_t *uid, gid_t *gid,
73 pid_t *pgrp, int *minproto, int *maxproto)
74{
75 char *p;
76 substring_t args[MAX_OPT_ARGS];
77 int option;
78
79 *uid = current_uid();
80 *gid = current_gid();
81 *pgrp = task_pgrp_nr(current);
82
83 *minproto = *maxproto = AUTOFS_PROTO_VERSION;
84
85 *pipefd = -1;
86
87 if (!options)
88 return 1;
89
90 while ((p = strsep(&options, ",")) != NULL) {
91 int token;
92 if (!*p)
93 continue;
94
95 token = match_token(p, autofs_tokens, args);
96 switch (token) {
97 case Opt_fd:
98 if (match_int(&args[0], &option))
99 return 1;
100 *pipefd = option;
101 break;
102 case Opt_uid:
103 if (match_int(&args[0], &option))
104 return 1;
105 *uid = option;
106 break;
107 case Opt_gid:
108 if (match_int(&args[0], &option))
109 return 1;
110 *gid = option;
111 break;
112 case Opt_pgrp:
113 if (match_int(&args[0], &option))
114 return 1;
115 *pgrp = option;
116 break;
117 case Opt_minproto:
118 if (match_int(&args[0], &option))
119 return 1;
120 *minproto = option;
121 break;
122 case Opt_maxproto:
123 if (match_int(&args[0], &option))
124 return 1;
125 *maxproto = option;
126 break;
127 default:
128 return 1;
129 }
130 }
131 return (*pipefd < 0);
132}
133
134int autofs_fill_super(struct super_block *s, void *data, int silent)
135{
136 struct inode * root_inode;
137 struct dentry * root;
138 struct file * pipe;
139 int pipefd;
140 struct autofs_sb_info *sbi;
141 int minproto, maxproto;
142 pid_t pgid;
143
144 save_mount_options(s, data);
145
146 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
147 if (!sbi)
148 goto fail_unlock;
149 DPRINTK(("autofs: starting up, sbi = %p\n",sbi));
150
151 s->s_fs_info = sbi;
152 sbi->magic = AUTOFS_SBI_MAGIC;
153 sbi->pipe = NULL;
154 sbi->catatonic = 1;
155 sbi->exp_timeout = 0;
156 autofs_initialize_hash(&sbi->dirhash);
157 sbi->queues = NULL;
158 memset(sbi->symlink_bitmap, 0, sizeof(long)*AUTOFS_SYMLINK_BITMAP_LEN);
159 sbi->next_dir_ino = AUTOFS_FIRST_DIR_INO;
160 s->s_blocksize = 1024;
161 s->s_blocksize_bits = 10;
162 s->s_magic = AUTOFS_SUPER_MAGIC;
163 s->s_op = &autofs_sops;
164 s->s_time_gran = 1;
165 sbi->sb = s;
166
167 root_inode = autofs_iget(s, AUTOFS_ROOT_INO);
168 if (IS_ERR(root_inode))
169 goto fail_free;
170 root = d_alloc_root(root_inode);
171 pipe = NULL;
172
173 if (!root)
174 goto fail_iput;
175
176
177 if (parse_options(data, &pipefd, &root_inode->i_uid,
178 &root_inode->i_gid, &pgid, &minproto,
179 &maxproto)) {
180 printk("autofs: called with bogus options\n");
181 goto fail_dput;
182 }
183
184
185 if (minproto > AUTOFS_PROTO_VERSION ||
186 maxproto < AUTOFS_PROTO_VERSION) {
187 printk("autofs: kernel does not match daemon version\n");
188 goto fail_dput;
189 }
190
191 DPRINTK(("autofs: pipe fd = %d, pgrp = %u\n", pipefd, pgid));
192 sbi->oz_pgrp = find_get_pid(pgid);
193
194 if (!sbi->oz_pgrp) {
195 printk("autofs: could not find process group %d\n", pgid);
196 goto fail_dput;
197 }
198
199 pipe = fget(pipefd);
200
201 if (!pipe) {
202 printk("autofs: could not open pipe file descriptor\n");
203 goto fail_put_pid;
204 }
205
206 if (!pipe->f_op || !pipe->f_op->write)
207 goto fail_fput;
208 sbi->pipe = pipe;
209 sbi->catatonic = 0;
210
211
212
213
214 s->s_root = root;
215 return 0;
216
217fail_fput:
218 printk("autofs: pipe file descriptor does not contain proper ops\n");
219 fput(pipe);
220fail_put_pid:
221 put_pid(sbi->oz_pgrp);
222fail_dput:
223 dput(root);
224 goto fail_free;
225fail_iput:
226 printk("autofs: get root dentry failed\n");
227 iput(root_inode);
228fail_free:
229 kfree(sbi);
230 s->s_fs_info = NULL;
231fail_unlock:
232 return -EINVAL;
233}
234
235struct inode *autofs_iget(struct super_block *sb, unsigned long ino)
236{
237 unsigned int n;
238 struct autofs_sb_info *sbi = autofs_sbi(sb);
239 struct inode *inode;
240
241 inode = iget_locked(sb, ino);
242 if (!inode)
243 return ERR_PTR(-ENOMEM);
244 if (!(inode->i_state & I_NEW))
245 return inode;
246
247
248
249 inode->i_op = &simple_dir_inode_operations;
250 inode->i_fop = &simple_dir_operations;
251 inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
252 inode->i_nlink = 2;
253 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
254
255 if (ino == AUTOFS_ROOT_INO) {
256 inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO | S_IWUSR;
257 inode->i_op = &autofs_root_inode_operations;
258 inode->i_fop = &autofs_root_operations;
259 goto done;
260 }
261
262 inode->i_uid = inode->i_sb->s_root->d_inode->i_uid;
263 inode->i_gid = inode->i_sb->s_root->d_inode->i_gid;
264
265 if (ino >= AUTOFS_FIRST_SYMLINK && ino < AUTOFS_FIRST_DIR_INO) {
266
267 struct autofs_symlink *sl;
268
269 n = ino - AUTOFS_FIRST_SYMLINK;
270 if (n >= AUTOFS_MAX_SYMLINKS || !test_bit(n,sbi->symlink_bitmap)) {
271 printk("autofs: Looking for bad symlink inode %u\n", (unsigned int) ino);
272 goto done;
273 }
274
275 inode->i_op = &autofs_symlink_inode_operations;
276 sl = &sbi->symlink[n];
277 inode->i_private = sl;
278 inode->i_mode = S_IFLNK | S_IRWXUGO;
279 inode->i_mtime.tv_sec = inode->i_ctime.tv_sec = sl->mtime;
280 inode->i_mtime.tv_nsec = inode->i_ctime.tv_nsec = 0;
281 inode->i_size = sl->len;
282 inode->i_nlink = 1;
283 }
284
285done:
286 unlock_new_inode(inode);
287 return inode;
288}
289
