NFSv4.1: use layout driver in global device cache

pnfs deviceids are unique per server, per layout type.
struct nfs_client is currently used to distinguish deviceids from
different nfs servers, yet these may clash between different layout
types on the same server.  Therefore, use the layout driver associated
with each deviceid at insertion time to look it up, unhash, or
delete it.

Signed-off-by: Benny Halevy <bhalevy@panasas.com>

fs/nfs/callback_proc.c

@@ -278,7 +278,7 @@ __be32 nfs4_callback_devicenotify(struct cb_devicenotifyargs *args,
 		if (dev->cbd_notify_type == NOTIFY_DEVICEID4_CHANGE)
 			dprintk("%s: NOTIFY_DEVICEID4_CHANGE not supported, "
 				"deleting instead\n", __func__);
-		nfs4_delete_deviceid(clp, &dev->cbd_dev_id);
+		nfs4_delete_deviceid(server->pnfs_curr_ld, clp, &dev->cbd_dev_id);
 	}
 
 out:

fs/nfs/nfs4filelayout.c

@@ -441,7 +441,8 @@ filelayout_check_layout(struct pnfs_layout_hdr *lo,
 	}
 
 	/* find and reference the deviceid */
-	d = nfs4_find_get_deviceid(NFS_SERVER(lo->plh_inode)->nfs_client, id);
+	d = nfs4_find_get_deviceid(NFS_SERVER(lo->plh_inode)->pnfs_curr_ld,
+				   NFS_SERVER(lo->plh_inode)->nfs_client, id);
 	if (d == NULL) {
 		dsaddr = get_device_info(lo->plh_inode, id, gfp_flags);
 		if (dsaddr == NULL)

fs/nfs/pnfs.h

@@ -171,9 +171,9 @@ struct nfs4_deviceid_node {
 };
 
 void nfs4_print_deviceid(const struct nfs4_deviceid *dev_id);
-struct nfs4_deviceid_node *nfs4_find_get_deviceid(const struct nfs_client *, const struct nfs4_deviceid *);
-struct nfs4_deviceid_node *nfs4_unhash_put_deviceid(const struct nfs_client *, const struct nfs4_deviceid *);
-void nfs4_delete_deviceid(const struct nfs_client *, const struct nfs4_deviceid *);
+struct nfs4_deviceid_node *nfs4_find_get_deviceid(const struct pnfs_layoutdriver_type *, const struct nfs_client *, const struct nfs4_deviceid *);
+struct nfs4_deviceid_node *nfs4_unhash_put_deviceid(const struct pnfs_layoutdriver_type *, const struct nfs_client *, const struct nfs4_deviceid *);
+void nfs4_delete_deviceid(const struct pnfs_layoutdriver_type *, const struct nfs_client *, const struct nfs4_deviceid *);
 void nfs4_init_deviceid_node(struct nfs4_deviceid_node *,
 			     const struct pnfs_layoutdriver_type *,
 			     const struct nfs_client *,

fs/nfs/pnfs_dev.c

@@ -67,14 +67,16 @@ nfs4_deviceid_hash(const struct nfs4_deviceid *id)
 }
 
 static struct nfs4_deviceid_node *
-_lookup_deviceid(const struct nfs_client *clp, const struct nfs4_deviceid *id,
+_lookup_deviceid(const struct pnfs_layoutdriver_type *ld,
+		 const struct nfs_client *clp, const struct nfs4_deviceid *id,
 		 long hash)
 {
 	struct nfs4_deviceid_node *d;
 	struct hlist_node *n;
 
 	hlist_for_each_entry_rcu(d, n, &nfs4_deviceid_cache[hash], node)
-		if (d->nfs_client == clp && !memcmp(&d->deviceid, id, sizeof(*id))) {
+		if (d->ld == ld && d->nfs_client == clp &&
+		    !memcmp(&d->deviceid, id, sizeof(*id))) {
 			if (atomic_read(&d->ref))
 				return d;
 			else
@@ -90,13 +92,14 @@ _lookup_deviceid(const struct nfs_client *clp, const struct nfs4_deviceid *id,
  * @id deviceid to look up
  */
 struct nfs4_deviceid_node *
-_find_get_deviceid(const struct nfs_client *clp, const struct nfs4_deviceid *id,
+_find_get_deviceid(const struct pnfs_layoutdriver_type *ld,
+		   const struct nfs_client *clp, const struct nfs4_deviceid *id,
 		   long hash)
 {
 	struct nfs4_deviceid_node *d;
 
 	rcu_read_lock();
-	d = _lookup_deviceid(clp, id, hash);
+	d = _lookup_deviceid(ld, clp, id, hash);
 	if (d && !atomic_inc_not_zero(&d->ref))
 		d = NULL;
 	rcu_read_unlock();
@@ -104,9 +107,10 @@ _find_get_deviceid(const struct nfs_client *clp, const struct nfs4_deviceid *id,
 }
 
 struct nfs4_deviceid_node *
-nfs4_find_get_deviceid(const struct nfs_client *clp, const struct nfs4_deviceid *id)
+nfs4_find_get_deviceid(const struct pnfs_layoutdriver_type *ld,
+		       const struct nfs_client *clp, const struct nfs4_deviceid *id)
 {
-	return _find_get_deviceid(clp, id, nfs4_deviceid_hash(id));
+	return _find_get_deviceid(ld, clp, id, nfs4_deviceid_hash(id));
 }
 EXPORT_SYMBOL_GPL(nfs4_find_get_deviceid);
 
@@ -119,13 +123,14 @@ EXPORT_SYMBOL_GPL(nfs4_find_get_deviceid);
  * @ret the unhashed node, if found and dereferenced to zero, NULL otherwise.
  */
 struct nfs4_deviceid_node *
-nfs4_unhash_put_deviceid(const struct nfs_client *clp, const struct nfs4_deviceid *id)
+nfs4_unhash_put_deviceid(const struct pnfs_layoutdriver_type *ld,
+			 const struct nfs_client *clp, const struct nfs4_deviceid *id)
 {
 	struct nfs4_deviceid_node *d;
 
 	spin_lock(&nfs4_deviceid_lock);
 	rcu_read_lock();
-	d = _lookup_deviceid(clp, id, nfs4_deviceid_hash(id));
+	d = _lookup_deviceid(ld, clp, id, nfs4_deviceid_hash(id));
 	rcu_read_unlock();
 	if (!d) {
 		spin_unlock(&nfs4_deviceid_lock);
@@ -150,11 +155,12 @@ EXPORT_SYMBOL_GPL(nfs4_unhash_put_deviceid);
  * @id deviceid to delete
  */
 void
-nfs4_delete_deviceid(const struct nfs_client *clp, const struct nfs4_deviceid *id)
+nfs4_delete_deviceid(const struct pnfs_layoutdriver_type *ld,
+		     const struct nfs_client *clp, const struct nfs4_deviceid *id)
 {
 	struct nfs4_deviceid_node *d;
 
-	d = nfs4_unhash_put_deviceid(clp, id);
+	d = nfs4_unhash_put_deviceid(ld, clp, id);
 	if (!d)
 		return;
 	d->ld->free_deviceid_node(d);
@@ -194,7 +200,7 @@ nfs4_insert_deviceid_node(struct nfs4_deviceid_node *new)
 
 	spin_lock(&nfs4_deviceid_lock);
 	hash = nfs4_deviceid_hash(&new->deviceid);
-	d = _find_get_deviceid(new->nfs_client, &new->deviceid, hash);
+	d = _find_get_deviceid(new->ld, new->nfs_client, &new->deviceid, hash);
 	if (d) {
 		spin_unlock(&nfs4_deviceid_lock);
 		return d;