{
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;
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",
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,
return wq;
}
+/*
+ * 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_wait_queue *wq;
+ struct autofs_info *ino;
+
+ /* Wait in progress, continue; */
+ wq = autofs4_find_wait(sbi, qstr);
+ if (wq) {
+ *wait = wq;
+ return 1;
+ }
+
+ *wait = NULL;
+
+ /* If we don't yet have any info this is a new request */
+ ino = autofs4_dentry_ino(dentry);
+ 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.
+ * 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))
+ return -EINTR;
+
+ wq = autofs4_find_wait(sbi, qstr);
+ if (wq) {
+ *wait = wq;
+ return 1;
+ }
+ }
+
+ /*
+ * 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.
+ */
+ 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_info *ino;
struct autofs_wait_queue *wq;
struct qstr qstr;
char *name;
- int status, type;
+ int status, ret, type;
/* In catatonic mode, we don't wait for nobody */
if (sbi->catatonic)
return -ENOENT;
-
+
+ if (!dentry->d_inode &&
+ (sbi->type & (AUTOFS_TYPE_DIRECT | AUTOFS_TYPE_OFFSET)))
+ return -ENOENT;
+
name = kmalloc(NAME_MAX + 1, GFP_KERNEL);
if (!name)
return -ENOMEM;
return -EINTR;
}
- wq = autofs4_find_wait(sbi, &qstr);
- 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(qstr.name);
- return -EINTR;
- }
- wq = autofs4_find_wait(sbi, &qstr);
- 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(qstr.name);
+ ret = validate_request(&wq, sbi, &qstr, dentry, notify);
+ if (ret <= 0) {
+ if (ret == 0)
mutex_unlock(&sbi->wq_mutex);
- return 0;
- }
+ kfree(qstr.name);
+ return ret;
}
if (!wq) {
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) {
/* 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(qstr.name);
DPRINTK("existing wait id = 0x%08lx, name = %.*s, nfy=%d",
wq->name.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.name) {
- kfree(wq->name.name);
- wq->name.name = NULL;
- }
- }
-
+ /*
+ * 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;
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.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;
}
projects / linux-2.6-omap-h63xx.git / blobdiff