NFS: Introduce nfs_detach_delegations()

Clean up:  Refactor code that takes clp->cl_lock and calls
nfs_detach_delegations_locked() into its own function.

While we're changing the call sites, get rid of the second parameter
and the logic in nfs_detach_delegations_locked() that uses it, since
callers always set that parameter of nfs_detach_delegations_locked()
to NULL.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

diff --git a/fs/nfs/delegation.c b/fs/nfs/delegation.c
index 1fd62fc49be36310b45e54028f69905b4e4f0237..521d71b8182514f936003f59ee36e4dd1ba0159f 100644 (file)
--- a/fs/nfs/delegation.c
+++ b/fs/nfs/delegation.c
@@ -175,9 +175,9 @@ static struct inode *nfs_delegation_grab_inode(struct nfs_delegation *delegation
        return inode;
 }
 
-static struct nfs_delegation *nfs_detach_delegation_locked(struct nfs_inode *nfsi,
-                                                          const nfs4_stateid *stateid,
-                                                          struct nfs_client *clp)
+static struct nfs_delegation *
+nfs_detach_delegation_locked(struct nfs_inode *nfsi,
+                            struct nfs_client *clp)
 {
        struct nfs_delegation *delegation =
                rcu_dereference_protected(nfsi->delegation,
@@ -185,22 +185,29 @@ static struct nfs_delegation *nfs_detach_delegation_locked(struct nfs_inode *nfs
 
        if (delegation == NULL)
                goto nomatch;
+
        spin_lock(&delegation->lock);
-       if (stateid != NULL && memcmp(delegation->stateid.data, stateid->data,
-                               sizeof(delegation->stateid.data)) != 0)
-               goto nomatch_unlock;
        list_del_rcu(&delegation->super_list);
        delegation->inode = NULL;
        nfsi->delegation_state = 0;
        rcu_assign_pointer(nfsi->delegation, NULL);
        spin_unlock(&delegation->lock);
        return delegation;
-nomatch_unlock:
-       spin_unlock(&delegation->lock);
 nomatch:
        return NULL;
 }
 
+static struct nfs_delegation *nfs_detach_delegation(struct nfs_inode *nfsi,
+                                                   struct nfs_client *clp)
+{
+       struct nfs_delegation *delegation;
+
+       spin_lock(&clp->cl_lock);
+       delegation = nfs_detach_delegation_locked(nfsi, clp);
+       spin_unlock(&clp->cl_lock);
+       return delegation;
+}
+
 /*
  * Set up a delegation on an inode
  */
@@ -246,7 +253,7 @@ int nfs_inode_set_delegation(struct inode *inode, struct rpc_cred *cred, struct
                        delegation = NULL;
                        goto out;
                }
-               freeme = nfs_detach_delegation_locked(nfsi, NULL, clp);
+               freeme = nfs_detach_delegation_locked(nfsi, clp);
        }
        list_add_rcu(&delegation->super_list, &clp->cl_delegations);
        nfsi->delegation_state = delegation->type;
@@ -307,9 +314,7 @@ restart:
                inode = nfs_delegation_grab_inode(delegation);
                if (inode == NULL)
                        continue;
-               spin_lock(&clp->cl_lock);
-               delegation = nfs_detach_delegation_locked(NFS_I(inode), NULL, clp);
-               spin_unlock(&clp->cl_lock);
+               delegation = nfs_detach_delegation(NFS_I(inode), clp);
                rcu_read_unlock();
                if (delegation != NULL) {
                        filemap_flush(inode->i_mapping);
@@ -338,9 +343,7 @@ void nfs_inode_return_delegation_noreclaim(struct inode *inode)
        struct nfs_delegation *delegation;
 
        if (rcu_access_pointer(nfsi->delegation) != NULL) {
-               spin_lock(&clp->cl_lock);
-               delegation = nfs_detach_delegation_locked(nfsi, NULL, clp);
-               spin_unlock(&clp->cl_lock);
+               delegation = nfs_detach_delegation(nfsi, clp);
                if (delegation != NULL)
                        nfs_do_return_delegation(inode, delegation, 0);
        }
@@ -354,9 +357,7 @@ int nfs_inode_return_delegation(struct inode *inode)
        int err = 0;
 
        if (rcu_access_pointer(nfsi->delegation) != NULL) {
-               spin_lock(&clp->cl_lock);
-               delegation = nfs_detach_delegation_locked(nfsi, NULL, clp);
-               spin_unlock(&clp->cl_lock);
+               delegation = nfs_detach_delegation(nfsi, clp);
                if (delegation != NULL) {
                        nfs_wb_all(inode);
                        err = __nfs_inode_return_delegation(inode, delegation, 1);
@@ -530,9 +531,7 @@ restart:
                inode = nfs_delegation_grab_inode(delegation);
                if (inode == NULL)
                        continue;
-               spin_lock(&clp->cl_lock);
-               delegation = nfs_detach_delegation_locked(NFS_I(inode), NULL, clp);
-               spin_unlock(&clp->cl_lock);
+               delegation = nfs_detach_delegation(NFS_I(inode), clp);
                rcu_read_unlock();
                if (delegation != NULL)
                        nfs_free_delegation(delegation);