NFSv4: Simplify _nfs4_do_access()

Currently, _nfs4_do_access() is just a copy of nfs_do_access() with added
conversion of the open flags into an access mask. This patch merges the
duplicate functionality.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

fs/nfs/dir.c

@@ -1815,7 +1815,7 @@ static struct nfs_access_entry *nfs_access_search_rbtree(struct inode *inode, st
 	return NULL;
 }
 
-int nfs_access_get_cached(struct inode *inode, struct rpc_cred *cred, struct nfs_access_entry *res)
+static int nfs_access_get_cached(struct inode *inode, struct rpc_cred *cred, struct nfs_access_entry *res)
 {
 	struct nfs_inode *nfsi = NFS_I(inode);
 	struct nfs_access_entry *cache;
@@ -1882,7 +1882,7 @@ static void nfs_access_add_rbtree(struct inode *inode, struct nfs_access_entry *
 	nfs_access_free_entry(entry);
 }
 
-void nfs_access_add_cache(struct inode *inode, struct nfs_access_entry *set)
+static void nfs_access_add_cache(struct inode *inode, struct nfs_access_entry *set)
 {
 	struct nfs_access_entry *cache = kmalloc(sizeof(*cache), GFP_KERNEL);
 	if (cache == NULL)
@@ -1930,6 +1930,24 @@ static int nfs_do_access(struct inode *inode, struct rpc_cred *cred, int mask)
 	return -EACCES;
 }
 
+static int nfs_open_permission_mask(int openflags)
+{
+	int mask = 0;
+
+	if (openflags & FMODE_READ)
+		mask |= MAY_READ;
+	if (openflags & FMODE_WRITE)
+		mask |= MAY_WRITE;
+	if (openflags & FMODE_EXEC)
+		mask |= MAY_EXEC;
+	return mask;
+}
+
+int nfs_may_open(struct inode *inode, struct rpc_cred *cred, int openflags)
+{
+	return nfs_do_access(inode, cred, nfs_open_permission_mask(openflags));
+}
+
 int nfs_permission(struct inode *inode, int mask, struct nameidata *nd)
 {
 	struct rpc_cred *cred;

fs/nfs/nfs4proc.c

@@ -65,7 +65,6 @@ static int nfs4_async_handle_error(struct rpc_task *, const struct nfs_server *)
 static int _nfs4_proc_access(struct inode *inode, struct nfs_access_entry *entry);
 static int nfs4_handle_exception(const struct nfs_server *server, int errorcode, struct nfs4_exception *exception);
 static int nfs4_wait_clnt_recover(struct rpc_clnt *clnt, struct nfs_client *clp);
-static int _nfs4_do_access(struct inode *inode, struct rpc_cred *cred, int openflags);
 static int _nfs4_proc_lookup(struct inode *dir, const struct qstr *name, struct nfs_fh *fhandle, struct nfs_fattr *fattr);
 static int _nfs4_proc_getattr(struct nfs_server *server, struct nfs_fh *fhandle, struct nfs_fattr *fattr);
 
@@ -454,7 +453,7 @@ static struct nfs4_state *nfs4_try_open_cached(struct nfs4_opendata *opendata)
 		memcpy(stateid.data, delegation->stateid.data, sizeof(stateid.data));
 		rcu_read_unlock();
 		lock_kernel();
-		ret = _nfs4_do_access(state->inode, state->owner->so_cred, open_mode);
+		ret = nfs_may_open(state->inode, state->owner->so_cred, open_mode);
 		unlock_kernel();
 		if (ret != 0)
 			goto out;
@@ -948,36 +947,6 @@ static int _nfs4_proc_open(struct nfs4_opendata *data)
 	return 0;
 }
 
-static int _nfs4_do_access(struct inode *inode, struct rpc_cred *cred, int openflags)
-{
-	struct nfs_access_entry cache;
-	int mask = 0;
-	int status;
-
-	if (openflags & FMODE_READ)
-		mask |= MAY_READ;
-	if (openflags & FMODE_WRITE)
-		mask |= MAY_WRITE;
-	if (openflags & FMODE_EXEC)
-		mask |= MAY_EXEC;
-	status = nfs_access_get_cached(inode, cred, &cache);
-	if (status == 0)
-		goto out;
-
-	/* Be clever: ask server to check for all possible rights */
-	cache.mask = MAY_EXEC | MAY_WRITE | MAY_READ;
-	cache.cred = cred;
-	cache.jiffies = jiffies;
-	status = _nfs4_proc_access(inode, &cache);
-	if (status != 0)
-		return status;
-	nfs_access_add_cache(inode, &cache);
-out:
-	if ((cache.mask & mask) == mask)
-		return 0;
-	return -EACCES;
-}
-
 static int nfs4_recover_expired_lease(struct nfs_server *server)
 {
 	struct nfs_client *clp = server->nfs_client;
@@ -1381,7 +1350,7 @@ static int nfs4_intent_set_file(struct nameidata *nd, struct path *path, struct
 
 	/* If the open_intent is for execute, we have an extra check to make */
 	if (nd->intent.open.flags & FMODE_EXEC) {
-		ret = _nfs4_do_access(state->inode,
+		ret = nfs_may_open(state->inode,
 				state->owner->so_cred,
 				nd->intent.open.flags);
 		if (ret < 0)

include/linux/nfs_fs.h

@@ -292,9 +292,6 @@ extern int nfs_refresh_inode(struct inode *, struct nfs_fattr *);
 extern int nfs_post_op_update_inode(struct inode *inode, struct nfs_fattr *fattr);
 extern int nfs_getattr(struct vfsmount *, struct dentry *, struct kstat *);
 extern int nfs_permission(struct inode *, int, struct nameidata *);
-extern int nfs_access_get_cached(struct inode *, struct rpc_cred *, struct nfs_access_entry *);
-extern void nfs_access_add_cache(struct inode *, struct nfs_access_entry *);
-extern void nfs_access_zap_cache(struct inode *inode);
 extern int nfs_open(struct inode *, struct file *);
 extern int nfs_release(struct inode *, struct file *);
 extern int nfs_attribute_timeout(struct inode *inode);
@@ -382,6 +379,8 @@ extern const struct file_operations nfs_dir_operations;
 extern struct dentry_operations nfs_dentry_operations;
 
 extern int nfs_instantiate(struct dentry *dentry, struct nfs_fh *fh, struct nfs_fattr *fattr);
+extern int nfs_may_open(struct inode *inode, struct rpc_cred *cred, int openflags);
+extern void nfs_access_zap_cache(struct inode *inode);
 
 /*
  * linux/fs/nfs/symlink.c