int autofs4_wait(struct autofs_sb_info *sbi, struct dentry *dentry,
enum autofs_notify notify)
{
struct autofs_wait_queue *wq;
struct qstr qstr;
char *name;
int status, ret, type;
/* In catatonic mode, we don't wait for nobody */
if (sbi->catatonic)
return -ENOENT;
if (!dentry->d_inode) {
/*
* A wait for a negative dentry is invalid for certain
* cases. A direct or offset mount "always" has its mount
* point directory created and so the request dentry must
* be positive or the map key doesn't exist. The situation
* is very similar for indirect mounts except only dentrys
* in the root of the autofs file system may be negative.
*/
if (autofs_type_trigger(sbi->type))
return -ENOENT;
else if (!IS_ROOT(dentry->d_parent))
return -ENOENT;
}
name = kmalloc(NAME_MAX + 1, GFP_KERNEL);
if (!name)
return -ENOMEM;
/* If this is a direct mount request create a dummy name */
if (IS_ROOT(dentry) && autofs_type_trigger(sbi->type))
qstr.len = sprintf(name, "%p", dentry);
else {
qstr.len = autofs4_getpath(sbi, dentry, &name);
if (!qstr.len) {
kfree(name);
return -ENOENT;
}
}
qstr.name = name;
qstr.hash = full_name_hash(name, qstr.len);
if (mutex_lock_interruptible(&sbi->wq_mutex)) {
kfree(qstr.name);
return -EINTR;
}
ret = validate_request(&wq, sbi, &qstr, dentry, notify);
if (ret <= 0) {
if (ret == 0)
mutex_unlock(&sbi->wq_mutex);
kfree(qstr.name);
return ret;
}
if (!wq) {
/* Create a new wait queue */
wq = kmalloc(sizeof(struct autofs_wait_queue),GFP_KERNEL);
if (!wq) {
kfree(qstr.name);
mutex_unlock(&sbi->wq_mutex);
return -ENOMEM;
}
wq->wait_queue_token = autofs4_next_wait_queue;
if (++autofs4_next_wait_queue == 0)
autofs4_next_wait_queue = 1;
wq->next = sbi->queues;
sbi->queues = wq;
init_waitqueue_head(&wq->queue);
memcpy(&wq->name, &qstr, sizeof(struct qstr));
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 */
wq->wait_ctr = 2;
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 = autofs_type_trigger(sbi->type) ?
autofs_ptype_missing_direct :
autofs_ptype_missing_indirect;
else
type = autofs_type_trigger(sbi->type) ?
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->name.len,
wq->name.name, notify);
/* autofs4_notify_daemon() may block */
autofs4_notify_daemon(sbi, wq, type);
} else {
wq->wait_ctr++;
mutex_unlock(&sbi->wq_mutex);
kfree(qstr.name);
DPRINTK("existing wait id = 0x%08lx, name = %.*s, nfy=%d",
(unsigned long) wq->wait_queue_token, wq->name.len,
wq->name.name, notify);
}
/*
* wq->name.name is NULL iff the lock is already released
* or the mount has been made catatonic.
*/
if (wq->name.name) {
/* Block all but "shutdown" signals while waiting */
sigset_t oldset;
unsigned long irqflags;
spin_lock_irqsave(¤t->sighand->siglock, irqflags);
oldset = current->blocked;
siginitsetinv(¤t->blocked, SHUTDOWN_SIGS & ~oldset.sig[0]);
recalc_sigpending();
spin_unlock_irqrestore(¤t->sighand->siglock, irqflags);
wait_event_interruptible(wq->queue, wq->name.name == NULL);
spin_lock_irqsave(¤t->sighand->siglock, irqflags);
current->blocked = oldset;
recalc_sigpending();
spin_unlock_irqrestore(¤t->sighand->siglock, irqflags);
} else {
DPRINTK("skipped sleeping");
}
status = wq->status;
/*
* For direct and offset mounts we need to track the requester's
* uid and gid in the dentry info struct. This is so it can be
* supplied, on request, by the misc device ioctl interface.
* This is needed during daemon resatart when reconnecting
* to existing, active, autofs mounts. The uid and gid (and
* related string values) may be used for macro substitution
* in autofs mount maps.
*/
if (!status) {
struct autofs_info *ino;
struct dentry *de = NULL;
/* direct mount or browsable map */
ino = autofs4_dentry_ino(dentry);
if (!ino) {
/* If not lookup actual dentry used */
de = d_lookup(dentry->d_parent, &dentry->d_name);
if (de)
ino = autofs4_dentry_ino(de);
}
/* Set mount requester */
if (ino) {
spin_lock(&sbi->fs_lock);
ino->uid = wq->uid;
ino->gid = wq->gid;
spin_unlock(&sbi->fs_lock);
}
if (de)
dput(de);
}
/* Are we the last process to need status? */
mutex_lock(&sbi->wq_mutex);
if (!--wq->wait_ctr)
kfree(wq);
mutex_unlock(&sbi->wq_mutex);
return status;
}
int autofs4_wait(struct autofs_sb_info *sbi, struct dentry *dentry,
enum autofs_notify notify)
{
struct autofs_wait_queue *wq;
char *name;
int len, status;
/* In catatonic mode, we don't wait for nobody */
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 (down_interruptible(&sbi->wq_sem)) {
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;
}
if ( !wq ) {
/* Can't wait for an expire if there's no mount */
if (notify == NFY_NONE && !d_mountpoint(dentry)) {
kfree(name);
up(&sbi->wq_sem);
return -ENOENT;
}
/* Create a new wait queue */
wq = kmalloc(sizeof(struct autofs_wait_queue), GFP_KERNEL);
if ( !wq ) {
kfree(name);
up(&sbi->wq_sem);
return -ENOMEM;
}
wq->wait_queue_token = autofs4_next_wait_queue;
if (++autofs4_next_wait_queue == 0)
autofs4_next_wait_queue = 1;
wq->next = sbi->queues;
sbi->queues = wq;
init_waitqueue_head(&wq->queue);
wq->hash = dentry->d_name.hash;
wq->name = name;
wq->len = len;
wq->status = -EINTR; /* Status return if interrupted */
atomic_set(&wq->wait_ctr, 2);
up(&sbi->wq_sem);
DPRINTK(("autofs4_wait: 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 */
if (notify != NFY_NONE) {
autofs4_notify_daemon(sbi,wq,
notify == NFY_MOUNT ?
autofs_ptype_missing :
autofs_ptype_expire_multi);
}
} else {
atomic_inc(&wq->wait_ctr);
up(&sbi->wq_sem);
kfree(name);
DPRINTK(("autofs4_wait: existing wait id = 0x%08lx, name = %.*s, nfy=%d\n",
(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 ) {
/* We might have slept, so check again for catatonic mode */
wq->status = -ENOENT;
if ( wq->name ) {
kfree(wq->name);
wq->name = NULL;
}
}
if ( wq->name ) {
/* Block all but "shutdown" signals while waiting */
sigset_t oldset;
unsigned long irqflags;
spin_lock_irqsave(¤t->sighand->siglock, irqflags);
oldset = current->blocked;
siginitsetinv(¤t->blocked, SHUTDOWN_SIGS & ~oldset.sig[0]);
recalc_sigpending();
spin_unlock_irqrestore(¤t->sighand->siglock, irqflags);
wait_event_interruptible(wq->queue, wq->name == NULL);
spin_lock_irqsave(¤t->sighand->siglock, irqflags);
current->blocked = oldset;
recalc_sigpending();
spin_unlock_irqrestore(¤t->sighand->siglock, irqflags);
} else {
DPRINTK(("autofs_wait: skipped sleeping\n"));
}
status = wq->status;
/* Are we the last process to need status? */
if (atomic_dec_and_test(&wq->wait_ctr))
kfree(wq);
return status;
}
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;
unsigned int len = 0;
unsigned int hash = 0;
int status, type;
/* In catatonic mode, we don't wait for nobody */
if (sbi->catatonic)
return -ENOENT;
name = kmalloc(NAME_MAX + 1, GFP_KERNEL);
if (!name)
return -ENOMEM;
/* If this is a direct mount request create a dummy name */
if (IS_ROOT(tx_cache_get_dentry(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 (mutex_lock_interruptible(&sbi->wq_mutex)) {
kfree(name);
return -EINTR;
}
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;
}
/*
* 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);
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) {
kfree(name);
mutex_unlock(&sbi->wq_mutex);
return -ENOMEM;
}
wq->wait_queue_token = autofs4_next_wait_queue;
if (++autofs4_next_wait_queue == 0)
autofs4_next_wait_queue = 1;
wq->next = sbi->queues;
sbi->queues = wq;
init_waitqueue_head(&wq->queue);
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);
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) {
/* We might have slept, so check again for catatonic mode */
wq->status = -ENOENT;
kfree(wq->name);
wq->name = NULL;
}
if (wq->name) {
/* Block all but "shutdown" signals while waiting */
sigset_t oldset;
unsigned long irqflags;
spin_lock_irqsave(¤t->sighand->siglock, irqflags);
oldset = current->blocked;
siginitsetinv(¤t->blocked, SHUTDOWN_SIGS & ~oldset.sig[0]);
recalc_sigpending();
spin_unlock_irqrestore(¤t->sighand->siglock, irqflags);
wait_event_interruptible(wq->queue, wq->name == NULL);
spin_lock_irqsave(¤t->sighand->siglock, irqflags);
current->blocked = oldset;
recalc_sigpending();
spin_unlock_irqrestore(¤t->sighand->siglock, irqflags);
} else {
DPRINTK("skipped sleeping");
}
status = wq->status;
/* Are we the last process to need status? */
if (atomic_dec_and_test(&wq->wait_ctr))
kfree(wq);
return status;
}
