if (ino->flags & AUTOFS_INF_PENDING)
goto out;
if (!autofs4_direct_busy(mnt, root, timeout, do_now)) {
- ino->flags |= AUTOFS_INF_EXPIRING;
- init_completion(&ino->expire_complete);
+ ino->flags |= AUTOFS_INF_NO_RCU;
spin_unlock(&sbi->fs_lock);
- return root;
+ synchronize_rcu();
+ spin_lock(&sbi->fs_lock);
+ if (!autofs4_direct_busy(mnt, root, timeout, do_now)) {
+ ino->flags |= AUTOFS_INF_EXPIRING;
+ smp_mb();
+ ino->flags &= ~AUTOFS_INF_NO_RCU;
+ init_completion(&ino->expire_complete);
+ spin_unlock(&sbi->fs_lock);
+ return root;
+ }
+ ino->flags &= ~AUTOFS_INF_NO_RCU;
}
out:
spin_unlock(&sbi->fs_lock);
dentry = NULL;
while ((dentry = get_next_positive_subdir(dentry, root))) {
spin_lock(&sbi->fs_lock);
- expired = should_expire(dentry, mnt, timeout, how);
- if (expired) {
+ ino = autofs4_dentry_ino(dentry);
+ if (ino->flags & AUTOFS_INF_NO_RCU)
+ expired = NULL;
+ else
+ expired = should_expire(dentry, mnt, timeout, how);
+ if (!expired) {
+ spin_unlock(&sbi->fs_lock);
+ continue;
+ }
+ ino = autofs4_dentry_ino(expired);
+ ino->flags |= AUTOFS_INF_NO_RCU;
+ spin_unlock(&sbi->fs_lock);
+ synchronize_rcu();
+ spin_lock(&sbi->fs_lock);
+ if (should_expire(expired, mnt, timeout, how)) {
if (expired != dentry)
dput(dentry);
goto found;
}
+
+ ino->flags &= ~AUTOFS_INF_NO_RCU;
+ if (expired != dentry)
+ dput(expired);
spin_unlock(&sbi->fs_lock);
}
return NULL;
found:
DPRINTK("returning %p %.*s",
expired, (int)expired->d_name.len, expired->d_name.name);
- ino = autofs4_dentry_ino(expired);
ino->flags |= AUTOFS_INF_EXPIRING;
+ smp_mb();
+ ino->flags &= ~AUTOFS_INF_NO_RCU;
init_completion(&ino->expire_complete);
spin_unlock(&sbi->fs_lock);
spin_lock(&sbi->lookup_lock);
int status;
/* Block on any pending expire */
+ if (!(ino->flags & (AUTOFS_INF_EXPIRING | AUTOFS_INF_NO_RCU)))
+ return 0;
+ if (rcu_walk)
+ return -ECHILD;
+
spin_lock(&sbi->fs_lock);
if (ino->flags & AUTOFS_INF_EXPIRING) {
spin_unlock(&sbi->fs_lock);
- if (rcu_walk)
- return -ECHILD;
DPRINTK("waiting for expire %p name=%.*s",
dentry, dentry->d_name.len, dentry->d_name.name);