blob: 3db70dae40d3a842de562c9fb4e26c29f9284239 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/* -*- c -*- --------------------------------------------------------------- *
2 *
3 * linux/fs/autofs/waitq.c
4 *
5 * Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved
Ian Kent5c0a32f2006-03-27 01:14:55 -08006 * Copyright 2001-2006 Ian Kent <raven@themaw.net>
Linus Torvalds1da177e2005-04-16 15:20:36 -07007 *
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/slab.h>
15#include <linux/time.h>
16#include <linux/signal.h>
17#include <linux/file.h>
18#include "autofs_i.h"
19
20/* We make this a static variable rather than a part of the superblock; it
21 is better if we don't reassign numbers easily even across filesystems */
22static autofs_wqt_t autofs4_next_wait_queue = 1;
23
24/* These are the signals we allow interrupting a pending mount */
25#define SHUTDOWN_SIGS (sigmask(SIGKILL) | sigmask(SIGINT) | sigmask(SIGQUIT))
26
27void autofs4_catatonic_mode(struct autofs_sb_info *sbi)
28{
29 struct autofs_wait_queue *wq, *nwq;
30
Ian Kent5a11d4d2008-07-23 21:30:17 -070031 mutex_lock(&sbi->wq_mutex);
32 if (sbi->catatonic) {
33 mutex_unlock(&sbi->wq_mutex);
34 return;
35 }
36
Linus Torvalds1da177e2005-04-16 15:20:36 -070037 DPRINTK("entering catatonic mode");
38
39 sbi->catatonic = 1;
40 wq = sbi->queues;
41 sbi->queues = NULL; /* Erase all wait queues */
Ian Kente77fbdd2006-03-27 01:14:49 -080042 while (wq) {
Linus Torvalds1da177e2005-04-16 15:20:36 -070043 nwq = wq->next;
44 wq->status = -ENOENT; /* Magic is gone - report failure */
Tim Gardner5140a8c2013-03-01 19:46:48 +080045 kfree(wq->name.name);
46 wq->name.name = NULL;
Ian Kent296f7bf2008-07-23 21:30:21 -070047 wq->wait_ctr--;
Linus Torvalds1da177e2005-04-16 15:20:36 -070048 wake_up_interruptible(&wq->queue);
49 wq = nwq;
50 }
Ian Kentba8df432006-11-14 02:03:29 -080051 fput(sbi->pipe); /* Close the pipe */
52 sbi->pipe = NULL;
Ian Kent5a11d4d2008-07-23 21:30:17 -070053 sbi->pipefd = -1;
54 mutex_unlock(&sbi->wq_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -070055}
56
Al Virod668dc52012-01-10 22:35:38 -050057static int autofs4_write(struct autofs_sb_info *sbi,
58 struct file *file, const void *addr, int bytes)
Linus Torvalds1da177e2005-04-16 15:20:36 -070059{
60 unsigned long sigpipe, flags;
61 mm_segment_t fs;
62 const char *data = (const char *)addr;
63 ssize_t wr = 0;
64
Linus Torvalds1da177e2005-04-16 15:20:36 -070065 sigpipe = sigismember(&current->pending.signal, SIGPIPE);
66
67 /* Save pointer to user space and point back to kernel space */
68 fs = get_fs();
69 set_fs(KERNEL_DS);
70
Al Virod668dc52012-01-10 22:35:38 -050071 mutex_lock(&sbi->pipe_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -070072 while (bytes &&
73 (wr = file->f_op->write(file,data,bytes,&file->f_pos)) > 0) {
74 data += wr;
75 bytes -= wr;
76 }
Ian Kent86380942012-01-13 20:41:46 +080077 mutex_unlock(&sbi->pipe_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -070078
79 set_fs(fs);
80
81 /* Keep the currently executing process from receiving a
82 SIGPIPE unless it was already supposed to get one */
83 if (wr == -EPIPE && !sigpipe) {
84 spin_lock_irqsave(&current->sighand->siglock, flags);
85 sigdelset(&current->pending.signal, SIGPIPE);
86 recalc_sigpending();
87 spin_unlock_irqrestore(&current->sighand->siglock, flags);
88 }
89
90 return (bytes > 0);
91}
Linus Torvaldsfcbf94b2012-04-28 08:29:56 -070092
Linus Torvalds1da177e2005-04-16 15:20:36 -070093static void autofs4_notify_daemon(struct autofs_sb_info *sbi,
94 struct autofs_wait_queue *wq,
95 int type)
96{
Ian Kente8514472007-02-20 13:58:09 -080097 union {
98 struct autofs_packet_hdr hdr;
99 union autofs_packet_union v4_pkt;
100 union autofs_v5_packet_union v5_pkt;
101 } pkt;
Ian Kente64be332008-07-23 21:30:20 -0700102 struct file *pipe = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700103 size_t pktsz;
104
105 DPRINTK("wait id = 0x%08lx, name = %.*s, type=%d",
Linus Torvalds2f84dd72011-08-08 11:55:20 -0700106 (unsigned long) wq->wait_queue_token, wq->name.len, wq->name.name, type);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700107
108 memset(&pkt,0,sizeof pkt); /* For security reasons */
109
110 pkt.hdr.proto_version = sbi->version;
111 pkt.hdr.type = type;
Al Viro87533332012-01-10 22:24:48 -0500112 mutex_lock(&sbi->wq_mutex);
113
114 /* Check if we have become catatonic */
115 if (sbi->catatonic) {
116 mutex_unlock(&sbi->wq_mutex);
117 return;
118 }
Ian Kent5c0a32f2006-03-27 01:14:55 -0800119 switch (type) {
120 /* Kernel protocol v4 missing and expire packets */
121 case autofs_ptype_missing:
122 {
Ian Kente8514472007-02-20 13:58:09 -0800123 struct autofs_packet_missing *mp = &pkt.v4_pkt.missing;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700124
125 pktsz = sizeof(*mp);
126
127 mp->wait_queue_token = wq->wait_queue_token;
Jeff Moyer70b52a02008-07-23 21:30:16 -0700128 mp->len = wq->name.len;
129 memcpy(mp->name, wq->name.name, wq->name.len);
130 mp->name[wq->name.len] = '\0';
Ian Kent5c0a32f2006-03-27 01:14:55 -0800131 break;
132 }
133 case autofs_ptype_expire_multi:
134 {
Ian Kente8514472007-02-20 13:58:09 -0800135 struct autofs_packet_expire_multi *ep = &pkt.v4_pkt.expire_multi;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700136
137 pktsz = sizeof(*ep);
138
139 ep->wait_queue_token = wq->wait_queue_token;
Jeff Moyer70b52a02008-07-23 21:30:16 -0700140 ep->len = wq->name.len;
141 memcpy(ep->name, wq->name.name, wq->name.len);
142 ep->name[wq->name.len] = '\0';
Ian Kent5c0a32f2006-03-27 01:14:55 -0800143 break;
144 }
145 /*
146 * Kernel protocol v5 packet for handling indirect and direct
147 * mount missing and expire requests
148 */
149 case autofs_ptype_missing_indirect:
150 case autofs_ptype_expire_indirect:
151 case autofs_ptype_missing_direct:
152 case autofs_ptype_expire_direct:
153 {
Ian Kente8514472007-02-20 13:58:09 -0800154 struct autofs_v5_packet *packet = &pkt.v5_pkt.v5_packet;
Eric W. Biederman45634cd2012-02-07 16:18:52 -0800155 struct user_namespace *user_ns = sbi->pipe->f_cred->user_ns;
Ian Kent5c0a32f2006-03-27 01:14:55 -0800156
Linus Torvaldsfcbf94b2012-04-28 08:29:56 -0700157 pktsz = sizeof(*packet);
158
Ian Kent5c0a32f2006-03-27 01:14:55 -0800159 packet->wait_queue_token = wq->wait_queue_token;
Jeff Moyer70b52a02008-07-23 21:30:16 -0700160 packet->len = wq->name.len;
161 memcpy(packet->name, wq->name.name, wq->name.len);
162 packet->name[wq->name.len] = '\0';
Ian Kent5c0a32f2006-03-27 01:14:55 -0800163 packet->dev = wq->dev;
164 packet->ino = wq->ino;
Eric W. Biederman45634cd2012-02-07 16:18:52 -0800165 packet->uid = from_kuid_munged(user_ns, wq->uid);
166 packet->gid = from_kgid_munged(user_ns, wq->gid);
Ian Kent5c0a32f2006-03-27 01:14:55 -0800167 packet->pid = wq->pid;
168 packet->tgid = wq->tgid;
169 break;
170 }
171 default:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700172 printk("autofs4_notify_daemon: bad type %d!\n", type);
Al Viro87533332012-01-10 22:24:48 -0500173 mutex_unlock(&sbi->wq_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700174 return;
175 }
176
Al Virocb0942b2012-08-27 14:48:26 -0400177 pipe = get_file(sbi->pipe);
Al Viro87533332012-01-10 22:24:48 -0500178
Ian Kente64be332008-07-23 21:30:20 -0700179 mutex_unlock(&sbi->wq_mutex);
180
Al Virod668dc52012-01-10 22:35:38 -0500181 if (autofs4_write(sbi, pipe, &pkt, pktsz))
Al Viro87533332012-01-10 22:24:48 -0500182 autofs4_catatonic_mode(sbi);
183 fput(pipe);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700184}
185
186static int autofs4_getpath(struct autofs_sb_info *sbi,
187 struct dentry *dentry, char **name)
188{
189 struct dentry *root = sbi->sb->s_root;
190 struct dentry *tmp;
Nick Piggin949854d2011-01-07 17:49:37 +1100191 char *buf;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700192 char *p;
Nick Piggin949854d2011-01-07 17:49:37 +1100193 int len;
194 unsigned seq;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700195
Nick Piggin949854d2011-01-07 17:49:37 +1100196rename_retry:
197 buf = *name;
198 len = 0;
Nick Pigginb5c84bf2011-01-07 17:49:38 +1100199
Nick Piggin949854d2011-01-07 17:49:37 +1100200 seq = read_seqbegin(&rename_lock);
201 rcu_read_lock();
Ian Kente7854722011-03-25 01:51:31 +0800202 spin_lock(&sbi->fs_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700203 for (tmp = dentry ; tmp != root ; tmp = tmp->d_parent)
204 len += tmp->d_name.len + 1;
205
Ian Kentcab09362008-05-01 04:35:07 -0700206 if (!len || --len > NAME_MAX) {
Ian Kente7854722011-03-25 01:51:31 +0800207 spin_unlock(&sbi->fs_lock);
Nick Piggin949854d2011-01-07 17:49:37 +1100208 rcu_read_unlock();
209 if (read_seqretry(&rename_lock, seq))
210 goto rename_retry;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700211 return 0;
212 }
213
214 *(buf + len) = '\0';
215 p = buf + len - dentry->d_name.len;
216 strncpy(p, dentry->d_name.name, dentry->d_name.len);
217
218 for (tmp = dentry->d_parent; tmp != root ; tmp = tmp->d_parent) {
219 *(--p) = '/';
220 p -= tmp->d_name.len;
221 strncpy(p, tmp->d_name.name, tmp->d_name.len);
222 }
Ian Kente7854722011-03-25 01:51:31 +0800223 spin_unlock(&sbi->fs_lock);
Nick Piggin949854d2011-01-07 17:49:37 +1100224 rcu_read_unlock();
225 if (read_seqretry(&rename_lock, seq))
226 goto rename_retry;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700227
228 return len;
229}
230
Ian Kenta5370552006-05-15 09:43:51 -0700231static struct autofs_wait_queue *
Jeff Moyer70b52a02008-07-23 21:30:16 -0700232autofs4_find_wait(struct autofs_sb_info *sbi, struct qstr *qstr)
Ian Kenta5370552006-05-15 09:43:51 -0700233{
234 struct autofs_wait_queue *wq;
235
236 for (wq = sbi->queues; wq; wq = wq->next) {
Jeff Moyer70b52a02008-07-23 21:30:16 -0700237 if (wq->name.hash == qstr->hash &&
238 wq->name.len == qstr->len &&
239 wq->name.name &&
240 !memcmp(wq->name.name, qstr->name, qstr->len))
Ian Kenta5370552006-05-15 09:43:51 -0700241 break;
242 }
243 return wq;
244}
245
Ian Kenta1362fe2008-07-23 21:30:19 -0700246/*
247 * Check if we have a valid request.
248 * Returns
249 * 1 if the request should continue.
250 * In this case we can return an autofs_wait_queue entry if one is
251 * found or NULL to idicate a new wait needs to be created.
252 * 0 or a negative errno if the request shouldn't continue.
253 */
254static int validate_request(struct autofs_wait_queue **wait,
255 struct autofs_sb_info *sbi,
256 struct qstr *qstr,
257 struct dentry*dentry, enum autofs_notify notify)
258{
259 struct autofs_wait_queue *wq;
260 struct autofs_info *ino;
261
Al Viro4041bcd2012-01-10 22:20:12 -0500262 if (sbi->catatonic)
263 return -ENOENT;
264
Ian Kenta1362fe2008-07-23 21:30:19 -0700265 /* Wait in progress, continue; */
266 wq = autofs4_find_wait(sbi, qstr);
267 if (wq) {
268 *wait = wq;
269 return 1;
270 }
271
272 *wait = NULL;
273
274 /* If we don't yet have any info this is a new request */
275 ino = autofs4_dentry_ino(dentry);
276 if (!ino)
277 return 1;
278
279 /*
280 * If we've been asked to wait on an existing expire (NFY_NONE)
281 * but there is no wait in the queue ...
282 */
283 if (notify == NFY_NONE) {
284 /*
285 * Either we've betean the pending expire to post it's
286 * wait or it finished while we waited on the mutex.
287 * So we need to wait till either, the wait appears
288 * or the expire finishes.
289 */
290
291 while (ino->flags & AUTOFS_INF_EXPIRING) {
292 mutex_unlock(&sbi->wq_mutex);
293 schedule_timeout_interruptible(HZ/10);
294 if (mutex_lock_interruptible(&sbi->wq_mutex))
295 return -EINTR;
296
Al Viro4041bcd2012-01-10 22:20:12 -0500297 if (sbi->catatonic)
298 return -ENOENT;
299
Ian Kenta1362fe2008-07-23 21:30:19 -0700300 wq = autofs4_find_wait(sbi, qstr);
301 if (wq) {
302 *wait = wq;
303 return 1;
304 }
305 }
306
307 /*
308 * Not ideal but the status has already gone. Of the two
309 * cases where we wait on NFY_NONE neither depend on the
310 * return status of the wait.
311 */
312 return 0;
313 }
314
315 /*
316 * If we've been asked to trigger a mount and the request
317 * completed while we waited on the mutex ...
318 */
319 if (notify == NFY_MOUNT) {
Ian Kent9e3fea12011-01-14 18:46:30 +0000320 struct dentry *new = NULL;
321 int valid = 1;
322
Ian Kenta1362fe2008-07-23 21:30:19 -0700323 /*
Ian Kent463aea12009-06-09 16:26:24 -0700324 * If the dentry was successfully mounted while we slept
325 * on the wait queue mutex we can return success. If it
326 * isn't mounted (doesn't have submounts for the case of
327 * a multi-mount with no mount at it's base) we can
328 * continue on and create a new request.
329 */
Ian Kent9e3fea12011-01-14 18:46:30 +0000330 if (!IS_ROOT(dentry)) {
331 if (dentry->d_inode && d_unhashed(dentry)) {
332 struct dentry *parent = dentry->d_parent;
333 new = d_lookup(parent, &dentry->d_name);
334 if (new)
335 dentry = new;
336 }
337 }
Ian Kent463aea12009-06-09 16:26:24 -0700338 if (have_submounts(dentry))
Ian Kent9e3fea12011-01-14 18:46:30 +0000339 valid = 0;
340
341 if (new)
342 dput(new);
343 return valid;
Ian Kenta1362fe2008-07-23 21:30:19 -0700344 }
345
346 return 1;
347}
348
Linus Torvalds1da177e2005-04-16 15:20:36 -0700349int autofs4_wait(struct autofs_sb_info *sbi, struct dentry *dentry,
350 enum autofs_notify notify)
351{
352 struct autofs_wait_queue *wq;
Jeff Moyer70b52a02008-07-23 21:30:16 -0700353 struct qstr qstr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700354 char *name;
Ian Kenta1362fe2008-07-23 21:30:19 -0700355 int status, ret, type;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700356
357 /* In catatonic mode, we don't wait for nobody */
Ian Kente77fbdd2006-03-27 01:14:49 -0800358 if (sbi->catatonic)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700359 return -ENOENT;
Ian Kenta1362fe2008-07-23 21:30:19 -0700360
Ian Kentc72305b2008-07-23 21:30:23 -0700361 if (!dentry->d_inode) {
362 /*
363 * A wait for a negative dentry is invalid for certain
364 * cases. A direct or offset mount "always" has its mount
365 * point directory created and so the request dentry must
366 * be positive or the map key doesn't exist. The situation
367 * is very similar for indirect mounts except only dentrys
368 * in the root of the autofs file system may be negative.
369 */
Ian Kenta92daf62009-01-06 14:42:08 -0800370 if (autofs_type_trigger(sbi->type))
Ian Kentc72305b2008-07-23 21:30:23 -0700371 return -ENOENT;
372 else if (!IS_ROOT(dentry->d_parent))
373 return -ENOENT;
374 }
Ian Kenteb3b1762008-07-23 21:30:22 -0700375
Linus Torvalds1da177e2005-04-16 15:20:36 -0700376 name = kmalloc(NAME_MAX + 1, GFP_KERNEL);
377 if (!name)
378 return -ENOMEM;
379
Ian Kent5c0a32f2006-03-27 01:14:55 -0800380 /* If this is a direct mount request create a dummy name */
Ian Kenta92daf62009-01-06 14:42:08 -0800381 if (IS_ROOT(dentry) && autofs_type_trigger(sbi->type))
Jeff Moyer70b52a02008-07-23 21:30:16 -0700382 qstr.len = sprintf(name, "%p", dentry);
Ian Kent5c0a32f2006-03-27 01:14:55 -0800383 else {
Jeff Moyer70b52a02008-07-23 21:30:16 -0700384 qstr.len = autofs4_getpath(sbi, dentry, &name);
385 if (!qstr.len) {
Ian Kent5c0a32f2006-03-27 01:14:55 -0800386 kfree(name);
387 return -ENOENT;
388 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700389 }
Jeff Moyer70b52a02008-07-23 21:30:16 -0700390 qstr.name = name;
391 qstr.hash = full_name_hash(name, qstr.len);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700392
Ian Kentf4c7da02008-07-23 21:30:19 -0700393 if (mutex_lock_interruptible(&sbi->wq_mutex)) {
394 kfree(qstr.name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700395 return -EINTR;
Ian Kentf4c7da02008-07-23 21:30:19 -0700396 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700397
Ian Kenta1362fe2008-07-23 21:30:19 -0700398 ret = validate_request(&wq, sbi, &qstr, dentry, notify);
399 if (ret <= 0) {
Al Viro4041bcd2012-01-10 22:20:12 -0500400 if (ret != -EINTR)
Ian Kenta5370552006-05-15 09:43:51 -0700401 mutex_unlock(&sbi->wq_mutex);
Ian Kenta1362fe2008-07-23 21:30:19 -0700402 kfree(qstr.name);
403 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700404 }
405
Ian Kente77fbdd2006-03-27 01:14:49 -0800406 if (!wq) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700407 /* Create a new wait queue */
408 wq = kmalloc(sizeof(struct autofs_wait_queue),GFP_KERNEL);
Ian Kente77fbdd2006-03-27 01:14:49 -0800409 if (!wq) {
Jeff Moyer70b52a02008-07-23 21:30:16 -0700410 kfree(qstr.name);
Ingo Molnar1d5599e2006-03-23 03:00:41 -0800411 mutex_unlock(&sbi->wq_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700412 return -ENOMEM;
413 }
414
415 wq->wait_queue_token = autofs4_next_wait_queue;
416 if (++autofs4_next_wait_queue == 0)
417 autofs4_next_wait_queue = 1;
418 wq->next = sbi->queues;
419 sbi->queues = wq;
420 init_waitqueue_head(&wq->queue);
Jeff Moyer70b52a02008-07-23 21:30:16 -0700421 memcpy(&wq->name, &qstr, sizeof(struct qstr));
Ian Kent5c0a32f2006-03-27 01:14:55 -0800422 wq->dev = autofs4_get_dev(sbi);
423 wq->ino = autofs4_get_ino(sbi);
David Howells0eb790e2008-11-14 10:38:46 +1100424 wq->uid = current_uid();
425 wq->gid = current_gid();
Ian Kent5c0a32f2006-03-27 01:14:55 -0800426 wq->pid = current->pid;
427 wq->tgid = current->tgid;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700428 wq->status = -EINTR; /* Status return if interrupted */
Ian Kent296f7bf2008-07-23 21:30:21 -0700429 wq->wait_ctr = 2;
Ingo Molnar1d5599e2006-03-23 03:00:41 -0800430 mutex_unlock(&sbi->wq_mutex);
Ian Kent3e7b1912006-03-27 01:14:59 -0800431
Ian Kent5c0a32f2006-03-27 01:14:55 -0800432 if (sbi->version < 5) {
433 if (notify == NFY_MOUNT)
434 type = autofs_ptype_missing;
435 else
436 type = autofs_ptype_expire_multi;
437 } else {
438 if (notify == NFY_MOUNT)
Ian Kenta92daf62009-01-06 14:42:08 -0800439 type = autofs_type_trigger(sbi->type) ?
Ian Kent5c0a32f2006-03-27 01:14:55 -0800440 autofs_ptype_missing_direct :
441 autofs_ptype_missing_indirect;
442 else
Ian Kenta92daf62009-01-06 14:42:08 -0800443 type = autofs_type_trigger(sbi->type) ?
Ian Kent5c0a32f2006-03-27 01:14:55 -0800444 autofs_ptype_expire_direct :
445 autofs_ptype_expire_indirect;
446 }
Ian Kent4dcd00b2005-05-01 08:59:16 -0700447
Ian Kent682d4fc2005-07-07 17:57:02 -0700448 DPRINTK("new wait id = 0x%08lx, name = %.*s, nfy=%d\n",
Jeff Moyer70b52a02008-07-23 21:30:16 -0700449 (unsigned long) wq->wait_queue_token, wq->name.len,
450 wq->name.name, notify);
Ian Kent4dcd00b2005-05-01 08:59:16 -0700451
452 /* autofs4_notify_daemon() may block */
453 autofs4_notify_daemon(sbi, wq, type);
Ian Kenta5370552006-05-15 09:43:51 -0700454 } else {
Ian Kent296f7bf2008-07-23 21:30:21 -0700455 wq->wait_ctr++;
Ian Kenta5370552006-05-15 09:43:51 -0700456 mutex_unlock(&sbi->wq_mutex);
Jeff Moyer70b52a02008-07-23 21:30:16 -0700457 kfree(qstr.name);
Ian Kenta5370552006-05-15 09:43:51 -0700458 DPRINTK("existing wait id = 0x%08lx, name = %.*s, nfy=%d",
Jeff Moyer70b52a02008-07-23 21:30:16 -0700459 (unsigned long) wq->wait_queue_token, wq->name.len,
460 wq->name.name, notify);
Ian Kent4dcd00b2005-05-01 08:59:16 -0700461 }
462
Ian Kent5a11d4d2008-07-23 21:30:17 -0700463 /*
464 * wq->name.name is NULL iff the lock is already released
465 * or the mount has been made catatonic.
466 */
Jeff Moyer70b52a02008-07-23 21:30:16 -0700467 if (wq->name.name) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700468 /* Block all but "shutdown" signals while waiting */
469 sigset_t oldset;
470 unsigned long irqflags;
471
472 spin_lock_irqsave(&current->sighand->siglock, irqflags);
473 oldset = current->blocked;
474 siginitsetinv(&current->blocked, SHUTDOWN_SIGS & ~oldset.sig[0]);
475 recalc_sigpending();
476 spin_unlock_irqrestore(&current->sighand->siglock, irqflags);
477
Jeff Moyer70b52a02008-07-23 21:30:16 -0700478 wait_event_interruptible(wq->queue, wq->name.name == NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700479
480 spin_lock_irqsave(&current->sighand->siglock, irqflags);
481 current->blocked = oldset;
482 recalc_sigpending();
483 spin_unlock_irqrestore(&current->sighand->siglock, irqflags);
484 } else {
485 DPRINTK("skipped sleeping");
486 }
487
488 status = wq->status;
489
Ian Kentc0f54d32008-10-15 22:02:52 -0700490 /*
491 * For direct and offset mounts we need to track the requester's
492 * uid and gid in the dentry info struct. This is so it can be
493 * supplied, on request, by the misc device ioctl interface.
494 * This is needed during daemon resatart when reconnecting
495 * to existing, active, autofs mounts. The uid and gid (and
496 * related string values) may be used for macro substitution
497 * in autofs mount maps.
498 */
499 if (!status) {
500 struct autofs_info *ino;
501 struct dentry *de = NULL;
502
503 /* direct mount or browsable map */
504 ino = autofs4_dentry_ino(dentry);
505 if (!ino) {
506 /* If not lookup actual dentry used */
507 de = d_lookup(dentry->d_parent, &dentry->d_name);
508 if (de)
509 ino = autofs4_dentry_ino(de);
510 }
511
512 /* Set mount requester */
513 if (ino) {
514 spin_lock(&sbi->fs_lock);
515 ino->uid = wq->uid;
516 ino->gid = wq->gid;
517 spin_unlock(&sbi->fs_lock);
518 }
519
520 if (de)
521 dput(de);
522 }
523
Linus Torvalds1da177e2005-04-16 15:20:36 -0700524 /* Are we the last process to need status? */
Ian Kent296f7bf2008-07-23 21:30:21 -0700525 mutex_lock(&sbi->wq_mutex);
526 if (!--wq->wait_ctr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700527 kfree(wq);
Ian Kent296f7bf2008-07-23 21:30:21 -0700528 mutex_unlock(&sbi->wq_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700529
530 return status;
531}
532
533
534int autofs4_wait_release(struct autofs_sb_info *sbi, autofs_wqt_t wait_queue_token, int status)
535{
536 struct autofs_wait_queue *wq, **wql;
537
Ingo Molnar1d5599e2006-03-23 03:00:41 -0800538 mutex_lock(&sbi->wq_mutex);
Stephen Hemmingerc80544d2007-10-18 03:07:05 -0700539 for (wql = &sbi->queues; (wq = *wql) != NULL; wql = &wq->next) {
Ian Kente77fbdd2006-03-27 01:14:49 -0800540 if (wq->wait_queue_token == wait_queue_token)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700541 break;
542 }
543
Ian Kente77fbdd2006-03-27 01:14:49 -0800544 if (!wq) {
Ingo Molnar1d5599e2006-03-23 03:00:41 -0800545 mutex_unlock(&sbi->wq_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700546 return -EINVAL;
547 }
548
549 *wql = wq->next; /* Unlink from chain */
Jeff Moyer70b52a02008-07-23 21:30:16 -0700550 kfree(wq->name.name);
551 wq->name.name = NULL; /* Do not wait on this queue */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700552 wq->status = status;
Ian Kent296f7bf2008-07-23 21:30:21 -0700553 wake_up_interruptible(&wq->queue);
554 if (!--wq->wait_ctr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700555 kfree(wq);
Ian Kent296f7bf2008-07-23 21:30:21 -0700556 mutex_unlock(&sbi->wq_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700557
558 return 0;
559}
560