Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 78 insertions, 0 deletions

diff --git a/fs/fscache/netfs.c b/fs/fscache/netfs.c
new file mode 100644
index 000000000..c2f605483
--- /dev/null
+++ b/fs/fscache/netfs.c
@@ -0,0 +1,78 @@
+/* FS-Cache netfs (client) registration
+ *
+ * Copyright (C) 2008 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+#define FSCACHE_DEBUG_LEVEL COOKIE
+#include <linux/module.h>
+#include <linux/slab.h>
+#include "internal.h"
+
+/*
+ * register a network filesystem for caching
+ */
+int __fscache_register_netfs(struct fscache_netfs *netfs)
+{
+	struct fscache_cookie *candidate, *cookie;
+
+	_enter("{%s}", netfs->name);
+
+	/* allocate a cookie for the primary index */
+	candidate = fscache_alloc_cookie(&fscache_fsdef_index,
+					 &fscache_fsdef_netfs_def,
+					 netfs->name, strlen(netfs->name),
+					 &netfs->version, sizeof(netfs->version),
+					 netfs, 0);
+	if (!candidate) {
+		_leave(" = -ENOMEM");
+		return -ENOMEM;
+	}
+
+	candidate->flags = 1 << FSCACHE_COOKIE_ENABLED;
+
+	/* check the netfs type is not already present */
+	cookie = fscache_hash_cookie(candidate);
+	if (!cookie)
+		goto already_registered;
+	if (cookie != candidate) {
+		trace_fscache_cookie(candidate, fscache_cookie_discard, 1);
+		fscache_free_cookie(candidate);
+	}
+
+	fscache_cookie_get(cookie->parent, fscache_cookie_get_register_netfs);
+	atomic_inc(&cookie->parent->n_children);
+
+	netfs->primary_index = cookie;
+
+	pr_notice("Netfs '%s' registered for caching\n", netfs->name);
+	trace_fscache_netfs(netfs);
+	_leave(" = 0");
+	return 0;
+
+already_registered:
+	fscache_cookie_put(candidate, fscache_cookie_put_dup_netfs);
+	_leave(" = -EEXIST");
+	return -EEXIST;
+}
+EXPORT_SYMBOL(__fscache_register_netfs);
+
+/*
+ * unregister a network filesystem from the cache
+ * - all cookies must have been released first
+ */
+void __fscache_unregister_netfs(struct fscache_netfs *netfs)
+{
+	_enter("{%s.%u}", netfs->name, netfs->version);
+
+	fscache_relinquish_cookie(netfs->primary_index, NULL, false);
+	pr_notice("Netfs '%s' unregistered from caching\n", netfs->name);
+
+	_leave("");
+}
+EXPORT_SYMBOL(__fscache_unregister_netfs);