NFSv4: Replace state_owner->so_owner_id with an ida based allocator

We're unlikely to ever need more than 2^31 simultaneous open owners,
so let's replace the custom allocator with the generic ida allocator.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 12 insertions, 5 deletions

diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c
index a8a42a677d8f..8472707286f9 100644
--- a/fs/nfs/nfs4state.c
+++ b/fs/nfs/nfs4state.c
@@ -405,6 +405,7 @@ nfs4_insert_state_owner_locked(struct nfs4_state_owner *new)
         struct rb_node **p = &server->state_owners.rb_node,
                        *parent = NULL;
         struct nfs4_state_owner *sp;
+        int err;
 
         while (*p != NULL) {
                 parent = *p;
@@ -421,8 +422,9 @@ nfs4_insert_state_owner_locked(struct nfs4_state_owner *new)
                         return sp;
                 }
         }
-        nfs_alloc_unique_id_locked(&server->openowner_id,
-                                        &new->so_owner_id, 1, 64);
+        err = ida_get_new(&server->openowner_id, &new->so_owner_id);
+        if (err)
+                return ERR_PTR(err);
         rb_link_node(&new->so_server_node, parent, p);
         rb_insert_color(&new->so_server_node, &server->state_owners);
         return new;
@@ -435,7 +437,7 @@ nfs4_remove_state_owner_locked(struct nfs4_state_owner *sp)
 
         if (!RB_EMPTY_NODE(&sp->so_server_node))
                 rb_erase(&sp->so_server_node, &server->state_owners);
-        nfs_free_unique_id(&server->openowner_id, &sp->so_owner_id);
+        ida_remove(&server->openowner_id, sp->so_owner_id);
 }
 
 /*
@@ -534,8 +536,13 @@ struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *server,
         new = nfs4_alloc_state_owner(server, cred, gfp_flags);
         if (new == NULL)
                 goto out;
-        sp = nfs4_insert_state_owner_locked(new);
-        spin_unlock(&clp->cl_lock);
+        do {
+                if (ida_pre_get(&server->openowner_id, gfp_flags) == 0)
+                        break;
+                spin_lock(&clp->cl_lock);
+                sp = nfs4_insert_state_owner_locked(new);
+                spin_unlock(&clp->cl_lock);
+        } while (sp == ERR_PTR(-EAGAIN));
         if (sp != new)
                 nfs4_free_state_owner(new);
 out: