NFS: fix umount of pnfs filesystems
Unmounting a pnfs filesystem hangs using filelayout and possibly others.
This fixes the use of the rcu protected node by making use of a new 'tmpnode'
for the temporary purge list. Also, the spinlock shouldn't be held when calling
synchronize_rcu().
Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/pnfs.h b/fs/nfs/pnfs.h
index 48d0a8e..96bf4e6 100644
--- a/fs/nfs/pnfs.h
+++ b/fs/nfs/pnfs.h
@@ -186,6 +186,7 @@
/* pnfs_dev.c */
struct nfs4_deviceid_node {
struct hlist_node node;
+ struct hlist_node tmpnode;
const struct pnfs_layoutdriver_type *ld;
const struct nfs_client *nfs_client;
struct nfs4_deviceid deviceid;
diff --git a/fs/nfs/pnfs_dev.c b/fs/nfs/pnfs_dev.c
index c65e133..5944d4b 100644
--- a/fs/nfs/pnfs_dev.c
+++ b/fs/nfs/pnfs_dev.c
@@ -174,6 +174,7 @@
const struct nfs4_deviceid *id)
{
INIT_HLIST_NODE(&d->node);
+ INIT_HLIST_NODE(&d->tmpnode);
d->ld = ld;
d->nfs_client = nfs_client;
d->deviceid = *id;
@@ -238,24 +239,29 @@
_deviceid_purge_client(const struct nfs_client *clp, long hash)
{
struct nfs4_deviceid_node *d;
- struct hlist_node *n, *next;
+ struct hlist_node *n;
HLIST_HEAD(tmp);
+ spin_lock(&nfs4_deviceid_lock);
rcu_read_lock();
hlist_for_each_entry_rcu(d, n, &nfs4_deviceid_cache[hash], node)
if (d->nfs_client == clp && atomic_read(&d->ref)) {
hlist_del_init_rcu(&d->node);
- hlist_add_head(&d->node, &tmp);
+ hlist_add_head(&d->tmpnode, &tmp);
}
rcu_read_unlock();
+ spin_unlock(&nfs4_deviceid_lock);
if (hlist_empty(&tmp))
return;
synchronize_rcu();
- hlist_for_each_entry_safe(d, n, next, &tmp, node)
+ while (!hlist_empty(&tmp)) {
+ d = hlist_entry(tmp.first, struct nfs4_deviceid_node, tmpnode);
+ hlist_del(&d->tmpnode);
if (atomic_dec_and_test(&d->ref))
d->ld->free_deviceid_node(d);
+ }
}
void
@@ -263,8 +269,8 @@
{
long h;
- spin_lock(&nfs4_deviceid_lock);
+ if (!(clp->cl_exchange_flags & EXCHGID4_FLAG_USE_PNFS_MDS))
+ return;
for (h = 0; h < NFS4_DEVICE_ID_HASH_SIZE; h++)
_deviceid_purge_client(clp, h);
- spin_unlock(&nfs4_deviceid_lock);
}