{
struct autofs_wait_queue *wq, *nwq;
+ mutex_lock(&sbi->wq_mutex);
+ if (sbi->catatonic) {
+ mutex_unlock(&sbi->wq_mutex);
+ return;
+ }
+
DPRINTK("entering catatonic mode");
sbi->catatonic = 1;
while (wq) {
nwq = wq->next;
wq->status = -ENOENT; /* Magic is gone - report failure */
- kfree(wq->name);
- wq->name = NULL;
+ if (wq->name.name) {
+ kfree(wq->name.name);
+ wq->name.name = NULL;
+ }
+ wq->wait_ctr--;
wake_up_interruptible(&wq->queue);
wq = nwq;
}
fput(sbi->pipe); /* Close the pipe */
sbi->pipe = NULL;
+ sbi->pipefd = -1;
+ mutex_unlock(&sbi->wq_mutex);
}
static int autofs4_write(struct file *file, const void *addr, int bytes)
union autofs_packet_union v4_pkt;
union autofs_v5_packet_union v5_pkt;
} pkt;
+ struct file *pipe = NULL;
size_t pktsz;
DPRINTK("wait id = 0x%08lx, name = %.*s, type=%d",
- wq->wait_queue_token, wq->len, wq->name, type);
+ wq->wait_queue_token, wq->name.len, wq->name.name, type);
memset(&pkt,0,sizeof pkt); /* For security reasons */
pktsz = sizeof(*mp);
mp->wait_queue_token = wq->wait_queue_token;
- mp->len = wq->len;
- memcpy(mp->name, wq->name, wq->len);
- mp->name[wq->len] = '\0';
+ mp->len = wq->name.len;
+ memcpy(mp->name, wq->name.name, wq->name.len);
+ mp->name[wq->name.len] = '\0';
break;
}
case autofs_ptype_expire_multi:
pktsz = sizeof(*ep);
ep->wait_queue_token = wq->wait_queue_token;
- ep->len = wq->len;
- memcpy(ep->name, wq->name, wq->len);
- ep->name[wq->len] = '\0';
+ ep->len = wq->name.len;
+ memcpy(ep->name, wq->name.name, wq->name.len);
+ ep->name[wq->name.len] = '\0';
break;
}
/*
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->len = wq->name.len;
+ memcpy(packet->name, wq->name.name, wq->name.len);
+ packet->name[wq->name.len] = '\0';
packet->dev = wq->dev;
packet->ino = wq->ino;
packet->uid = wq->uid;
return;
}
- if (autofs4_write(sbi->pipe, &pkt, pktsz))
- autofs4_catatonic_mode(sbi);
+ /* Check if we have become catatonic */
+ mutex_lock(&sbi->wq_mutex);
+ if (!sbi->catatonic) {
+ pipe = sbi->pipe;
+ get_file(pipe);
+ }
+ mutex_unlock(&sbi->wq_mutex);
+
+ if (pipe) {
+ if (autofs4_write(pipe, &pkt, pktsz))
+ autofs4_catatonic_mode(sbi);
+ fput(pipe);
+ }
}
static int autofs4_getpath(struct autofs_sb_info *sbi,
}
static struct autofs_wait_queue *
-autofs4_find_wait(struct autofs_sb_info *sbi,
- char *name, unsigned int hash, unsigned int len)
+autofs4_find_wait(struct autofs_sb_info *sbi, struct qstr *qstr)
{
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))
+ if (wq->name.hash == qstr->hash &&
+ wq->name.len == qstr->len &&
+ wq->name.name &&
+ !memcmp(wq->name.name, qstr->name, qstr->len))
break;
}
return wq;
}
-int autofs4_wait(struct autofs_sb_info *sbi, struct dentry *dentry,
- enum autofs_notify notify)
+/*
+ * Check if we have a valid request.
+ * Returns
+ * 1 if the request should continue.
+ * In this case we can return an autofs_wait_queue entry if one is
+ * found or NULL to idicate a new wait needs to be created.
+ * 0 or a negative errno if the request shouldn't continue.
+ */
+static int validate_request(struct autofs_wait_queue **wait,
+ struct autofs_sb_info *sbi,
+ struct qstr *qstr,
+ 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;
+ struct autofs_info *ino;
- /* 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;
- }
+ /* Wait in progress, continue; */
+ wq = autofs4_find_wait(sbi, qstr);
+ if (wq) {
+ *wait = wq;
+ return 1;
}
- hash = full_name_hash(name, len);
- if (mutex_lock_interruptible(&sbi->wq_mutex)) {
- kfree(name);
- return -EINTR;
- }
+ *wait = NULL;
- wq = autofs4_find_wait(sbi, name, hash, len);
+ /* If we don't yet have any info this is a new request */
ino = autofs4_dentry_ino(dentry);
- if (!wq && ino && notify == NFY_NONE) {
+ if (!ino)
+ return 1;
+
+ /*
+ * If we've been asked to wait on an existing expire (NFY_NONE)
+ * but there is no wait in the queue ...
+ */
+ if (notify == NFY_NONE) {
/*
* Either we've betean the pending expire to post it's
* wait or it finished while we waited on the mutex.
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);
+ if (mutex_lock_interruptible(&sbi->wq_mutex))
return -EINTR;
+
+ wq = autofs4_find_wait(sbi, qstr);
+ if (wq) {
+ *wait = wq;
+ return 1;
}
- wq = autofs4_find_wait(sbi, name, hash, len);
- if (wq)
- break;
}
/*
* cases where we wait on NFY_NONE neither depend on the
* return status of the wait.
*/
- if (!wq) {
+ return 0;
+ }
+
+ /*
+ * If we've been asked to trigger a mount and the request
+ * completed while we waited on the mutex ...
+ */
+ if (notify == NFY_MOUNT) {
+ /*
+ * If the dentry isn't hashed just go ahead and try the
+ * mount again with a new wait (not much else we can do).
+ */
+ if (!d_unhashed(dentry)) {
+ /*
+ * But if the dentry is hashed, that means that we
+ * got here through the revalidate path. Thus, we
+ * need to check if the dentry has been mounted
+ * while we waited on the wq_mutex. If it has,
+ * simply return success.
+ */
+ if (d_mountpoint(dentry))
+ return 0;
+ }
+ }
+
+ return 1;
+}
+
+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 (sbi->type & (AUTOFS_TYPE_DIRECT|AUTOFS_TYPE_OFFSET))
+ 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) && (sbi->type & AUTOFS_TYPE_DIRECT))
+ qstr.len = sprintf(name, "%p", dentry);
+ else {
+ qstr.len = autofs4_getpath(sbi, dentry, &name);
+ if (!qstr.len) {
kfree(name);
- mutex_unlock(&sbi->wq_mutex);
- return 0;
+ 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(name);
+ kfree(qstr.name);
mutex_unlock(&sbi->wq_mutex);
return -ENOMEM;
}
wq->next = sbi->queues;
sbi->queues = wq;
init_waitqueue_head(&wq->queue);
- wq->hash = hash;
- wq->name = name;
- wq->len = len;
+ memcpy(&wq->name, &qstr, sizeof(struct qstr));
wq->dev = autofs4_get_dev(sbi);
wq->ino = autofs4_get_ino(sbi);
wq->uid = current->uid;
wq->pid = current->pid;
wq->tgid = current->tgid;
wq->status = -EINTR; /* Status return if interrupted */
- atomic_set(&wq->wait_ctr, 2);
+ wq->wait_ctr = 2;
mutex_unlock(&sbi->wq_mutex);
if (sbi->version < 5) {
}
DPRINTK("new wait id = 0x%08lx, name = %.*s, nfy=%d\n",
- (unsigned long) wq->wait_queue_token, wq->len, wq->name, notify);
+ (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 {
- atomic_inc(&wq->wait_ctr);
+ wq->wait_ctr++;
mutex_unlock(&sbi->wq_mutex);
- kfree(name);
+ kfree(qstr.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;
+ (unsigned long) wq->wait_queue_token, wq->name.len,
+ wq->name.name, notify);
}
- if (wq->name) {
+ /*
+ * 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;
recalc_sigpending();
spin_unlock_irqrestore(¤t->sighand->siglock, irqflags);
- wait_event_interruptible(wq->queue, wq->name == NULL);
+ wait_event_interruptible(wq->queue, wq->name.name == NULL);
spin_lock_irqsave(¤t->sighand->siglock, irqflags);
current->blocked = oldset;
status = wq->status;
/* Are we the last process to need status? */
- if (atomic_dec_and_test(&wq->wait_ctr))
+ mutex_lock(&sbi->wq_mutex);
+ if (!--wq->wait_ctr)
kfree(wq);
+ mutex_unlock(&sbi->wq_mutex);
return status;
}
}
*wql = wq->next; /* Unlink from chain */
- mutex_unlock(&sbi->wq_mutex);
- kfree(wq->name);
- wq->name = NULL; /* Do not wait on this queue */
-
+ kfree(wq->name.name);
+ wq->name.name = NULL; /* Do not wait on this queue */
wq->status = status;
-
- if (atomic_dec_and_test(&wq->wait_ctr)) /* Is anyone still waiting for this guy? */
+ wake_up_interruptible(&wq->queue);
+ if (!--wq->wait_ctr)
kfree(wq);
- else
- wake_up_interruptible(&wq->queue);
+ mutex_unlock(&sbi->wq_mutex);
return 0;
}
git.openpandora.org / pandora-kernel.git / blobdiff