* linux/fs/autofs/waitq.c
*
* Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved
- * Copyright 2001-2003 Ian Kent <raven@themaw.net>
+ * Copyright 2001-2006 Ian Kent <raven@themaw.net>
*
* This file is part of the Linux kernel and is made available under
* the terms of the GNU General Public License, version 2, or at your
sbi->catatonic = 1;
wq = sbi->queues;
sbi->queues = NULL; /* Erase all wait queues */
- while ( wq ) {
+ while (wq) {
nwq = wq->next;
wq->status = -ENOENT; /* Magic is gone - report failure */
kfree(wq->name);
wake_up_interruptible(&wq->queue);
wq = nwq;
}
- if (sbi->pipe) {
- fput(sbi->pipe); /* Close the pipe */
- sbi->pipe = NULL;
- }
-
- shrink_dcache_sb(sbi->sb);
+ fput(sbi->pipe); /* Close the pipe */
+ sbi->pipe = NULL;
}
static int autofs4_write(struct file *file, const void *addr, int bytes)
pkt.hdr.proto_version = sbi->version;
pkt.hdr.type = type;
- if (type == autofs_ptype_missing) {
+ switch (type) {
+ /* Kernel protocol v4 missing and expire packets */
+ case autofs_ptype_missing:
+ {
struct autofs_packet_missing *mp = &pkt.missing;
pktsz = sizeof(*mp);
mp->len = wq->len;
memcpy(mp->name, wq->name, wq->len);
mp->name[wq->len] = '\0';
- } else if (type == autofs_ptype_expire_multi) {
+ break;
+ }
+ case autofs_ptype_expire_multi:
+ {
struct autofs_packet_expire_multi *ep = &pkt.expire_multi;
pktsz = sizeof(*ep);
ep->len = wq->len;
memcpy(ep->name, wq->name, wq->len);
ep->name[wq->len] = '\0';
- } else {
+ break;
+ }
+ /*
+ * Kernel protocol v5 packet for handling indirect and direct
+ * mount missing and expire requests
+ */
+ case autofs_ptype_missing_indirect:
+ case autofs_ptype_expire_indirect:
+ case autofs_ptype_missing_direct:
+ case autofs_ptype_expire_direct:
+ {
+ struct autofs_v5_packet *packet = &pkt.v5_packet;
+
+ pktsz = sizeof(*packet);
+
+ packet->wait_queue_token = wq->wait_queue_token;
+ packet->len = wq->len;
+ memcpy(packet->name, wq->name, wq->len);
+ packet->name[wq->len] = '\0';
+ packet->dev = wq->dev;
+ packet->ino = wq->ino;
+ packet->uid = wq->uid;
+ packet->gid = wq->gid;
+ packet->pid = wq->pid;
+ packet->tgid = wq->tgid;
+ break;
+ }
+ default:
printk("autofs4_notify_daemon: bad type %d!\n", type);
return;
}
return len;
}
+static struct autofs_wait_queue *
+autofs4_find_wait(struct autofs_sb_info *sbi,
+ char *name, unsigned int hash, unsigned int len)
+{
+ struct autofs_wait_queue *wq;
+
+ for (wq = sbi->queues; wq; wq = wq->next) {
+ if (wq->hash == hash &&
+ wq->len == len &&
+ wq->name && !memcmp(wq->name, name, len))
+ break;
+ }
+ return wq;
+}
+
int autofs4_wait(struct autofs_sb_info *sbi, struct dentry *dentry,
enum autofs_notify notify)
{
+ struct autofs_info *ino;
struct autofs_wait_queue *wq;
char *name;
- int len, status;
+ unsigned int len = 0;
+ unsigned int hash = 0;
+ int status, type;
/* In catatonic mode, we don't wait for nobody */
- if ( sbi->catatonic )
+ if (sbi->catatonic)
return -ENOENT;
name = kmalloc(NAME_MAX + 1, GFP_KERNEL);
if (!name)
return -ENOMEM;
- len = autofs4_getpath(sbi, dentry, &name);
- if (!len) {
- kfree(name);
- return -ENOENT;
+ /* If this is a direct mount request create a dummy name */
+ if (IS_ROOT(dentry) && (sbi->type & AUTOFS_TYPE_DIRECT))
+ len = sprintf(name, "%p", dentry);
+ else {
+ len = autofs4_getpath(sbi, dentry, &name);
+ if (!len) {
+ kfree(name);
+ return -ENOENT;
+ }
}
+ hash = full_name_hash(name, len);
- if (down_interruptible(&sbi->wq_sem)) {
+ if (mutex_lock_interruptible(&sbi->wq_mutex)) {
kfree(name);
return -EINTR;
}
- for (wq = sbi->queues ; wq ; wq = wq->next) {
- if (wq->hash == dentry->d_name.hash &&
- wq->len == len &&
- wq->name && !memcmp(wq->name, name, len))
- break;
- }
+ wq = autofs4_find_wait(sbi, name, hash, len);
+ ino = autofs4_dentry_ino(dentry);
+ if (!wq && ino && notify == NFY_NONE) {
+ /*
+ * Either we've betean the pending expire to post it's
+ * wait or it finished while we waited on the mutex.
+ * So we need to wait till either, the wait appears
+ * or the expire finishes.
+ */
+
+ while (ino->flags & AUTOFS_INF_EXPIRING) {
+ mutex_unlock(&sbi->wq_mutex);
+ schedule_timeout_interruptible(HZ/10);
+ if (mutex_lock_interruptible(&sbi->wq_mutex)) {
+ kfree(name);
+ return -EINTR;
+ }
+ wq = autofs4_find_wait(sbi, name, hash, len);
+ if (wq)
+ break;
+ }
- if ( !wq ) {
- /* Can't wait for an expire if there's no mount */
- if (notify == NFY_NONE && !d_mountpoint(dentry)) {
+ /*
+ * Not ideal but the status has already gone. Of the two
+ * cases where we wait on NFY_NONE neither depend on the
+ * return status of the wait.
+ */
+ if (!wq) {
kfree(name);
- up(&sbi->wq_sem);
- return -ENOENT;
+ mutex_unlock(&sbi->wq_mutex);
+ return 0;
}
+ }
+ if (!wq) {
/* Create a new wait queue */
wq = kmalloc(sizeof(struct autofs_wait_queue),GFP_KERNEL);
- if ( !wq ) {
+ if (!wq) {
kfree(name);
- up(&sbi->wq_sem);
+ mutex_unlock(&sbi->wq_mutex);
return -ENOMEM;
}
wq->next = sbi->queues;
sbi->queues = wq;
init_waitqueue_head(&wq->queue);
- wq->hash = dentry->d_name.hash;
+ wq->hash = hash;
wq->name = name;
wq->len = len;
+ wq->dev = autofs4_get_dev(sbi);
+ wq->ino = autofs4_get_ino(sbi);
+ wq->uid = current->uid;
+ wq->gid = current->gid;
+ wq->pid = current->pid;
+ wq->tgid = current->tgid;
wq->status = -EINTR; /* Status return if interrupted */
atomic_set(&wq->wait_ctr, 2);
- atomic_set(&wq->notified, 1);
- up(&sbi->wq_sem);
- } else {
- atomic_inc(&wq->wait_ctr);
- up(&sbi->wq_sem);
- kfree(name);
- DPRINTK("existing wait id = 0x%08lx, name = %.*s, nfy=%d",
- (unsigned long) wq->wait_queue_token, wq->len, wq->name, notify);
- }
-
- if (notify != NFY_NONE && atomic_dec_and_test(&wq->notified)) {
- int type = (notify == NFY_MOUNT ?
- autofs_ptype_missing : autofs_ptype_expire_multi);
+ mutex_unlock(&sbi->wq_mutex);
+
+ if (sbi->version < 5) {
+ if (notify == NFY_MOUNT)
+ type = autofs_ptype_missing;
+ else
+ type = autofs_ptype_expire_multi;
+ } else {
+ if (notify == NFY_MOUNT)
+ type = (sbi->type & AUTOFS_TYPE_DIRECT) ?
+ autofs_ptype_missing_direct :
+ autofs_ptype_missing_indirect;
+ else
+ type = (sbi->type & AUTOFS_TYPE_DIRECT) ?
+ autofs_ptype_expire_direct :
+ autofs_ptype_expire_indirect;
+ }
DPRINTK("new wait id = 0x%08lx, name = %.*s, nfy=%d\n",
(unsigned long) wq->wait_queue_token, wq->len, wq->name, notify);
/* autofs4_notify_daemon() may block */
autofs4_notify_daemon(sbi, wq, type);
+ } else {
+ atomic_inc(&wq->wait_ctr);
+ mutex_unlock(&sbi->wq_mutex);
+ kfree(name);
+ DPRINTK("existing wait id = 0x%08lx, name = %.*s, nfy=%d",
+ (unsigned long) wq->wait_queue_token, wq->len, wq->name, notify);
}
/* wq->name is NULL if and only if the lock is already released */
- if ( sbi->catatonic ) {
+ if (sbi->catatonic) {
/* We might have slept, so check again for catatonic mode */
wq->status = -ENOENT;
kfree(wq->name);
wq->name = NULL;
}
- if ( wq->name ) {
+ if (wq->name) {
/* Block all but "shutdown" signals while waiting */
sigset_t oldset;
unsigned long irqflags;
{
struct autofs_wait_queue *wq, **wql;
- down(&sbi->wq_sem);
- for ( wql = &sbi->queues ; (wq = *wql) != 0 ; wql = &wq->next ) {
- if ( wq->wait_queue_token == wait_queue_token )
+ mutex_lock(&sbi->wq_mutex);
+ for (wql = &sbi->queues ; (wq = *wql) != 0 ; wql = &wq->next) {
+ if (wq->wait_queue_token == wait_queue_token)
break;
}
- if ( !wq ) {
- up(&sbi->wq_sem);
+ if (!wq) {
+ mutex_unlock(&sbi->wq_mutex);
return -EINVAL;
}
*wql = wq->next; /* Unlink from chain */
- up(&sbi->wq_sem);
+ mutex_unlock(&sbi->wq_mutex);
kfree(wq->name);
wq->name = NULL; /* Do not wait on this queue */
git://git.onelab.eu / linux-2.6.git / blobdiff