Import a FreeBSD port of the FUSE Linux module.

This has been developed during 2 summer of code mandates and being revived
by gnn recently.
The functionality in this commit mirrors entirely content of fusefs-kmod
port, which doesn't need to be installed anymore for -CURRENT setups.

In order to get some sparse technical notes, please refer to:
http://lists.freebsd.org/pipermail/freebsd-fs/2012-March/013876.html

or to the project branch:
svn://svn.freebsd.org/base/projects/fuse/

which also contains granular history of changes happened during port
refinements. This commit does not came from the branch reintegration
itself because it seems svn is not behaving properly for this functionaly
at the moment.

Partly Sponsored by:		Google, Summer of Code program 2005, 2011
Originally submitted by:	ilya, Csaba Henk <csaba-ml AT creo DOT hu >
In collabouration with:		pho
Tested by:			flo, gnn, Gustau Perez,
				Kevin Oberman <rkoberman AT gmail DOT com>
MFC after:			2 months

1 files changed, 162 insertions, 0 deletions

diff --git a/sys/fs/fuse/fuse_main.c b/sys/fs/fuse/fuse_main.c
new file mode 100644
index 0000000..bf73a45f
--- /dev/null
+++ b/sys/fs/fuse/fuse_main.c
@@ -0,0 +1,162 @@
+/*
+ * Copyright (c) 2007-2009 Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above
+ *   copyright notice, this list of conditions and the following disclaimer
+ *   in the documentation and/or other materials provided with the
+ *   distribution.
+ * * Neither the name of Google Inc. nor the names of its
+ *   contributors may be used to endorse or promote products derived from
+ *   this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Copyright (C) 2005 Csaba Henk.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/types.h>
+#include <sys/module.h>
+#include <sys/systm.h>
+#include <sys/errno.h>
+#include <sys/param.h>
+#include <sys/kernel.h>
+#include <sys/conf.h>
+#include <sys/mutex.h>
+#include <sys/proc.h>
+#include <sys/mount.h>
+#include <sys/vnode.h>
+#include <sys/stat.h>
+#include <sys/file.h>
+#include <sys/buf.h>
+#include <sys/sysctl.h>
+
+#include "fuse.h"
+
+static void fuse_bringdown(eventhandler_tag eh_tag);
+static int fuse_loader(struct module *m, int what, void *arg);
+
+struct mtx fuse_mtx;
+
+extern struct vfsops fuse_vfsops;
+extern struct cdevsw fuse_cdevsw;
+extern struct vop_vector fuse_vnops;
+extern int fuse_pbuf_freecnt;
+
+static struct vfsconf fuse_vfsconf = {
+	.vfc_version = VFS_VERSION,
+	.vfc_name = "fusefs",
+	.vfc_vfsops = &fuse_vfsops,
+	.vfc_typenum = -1,
+	.vfc_flags = VFCF_SYNTHETIC
+};
+
+SYSCTL_INT(_vfs_fuse, OID_AUTO, kernelabi_major, CTLFLAG_RD,
+    0, FUSE_KERNEL_VERSION, "FUSE kernel abi major version");
+SYSCTL_INT(_vfs_fuse, OID_AUTO, kernelabi_minor, CTLFLAG_RD,
+    0, FUSE_KERNEL_MINOR_VERSION, "FUSE kernel abi minor version");
+
+/******************************
+ *
+ * >>> Module management stuff
+ *
+ ******************************/
+
+static void
+fuse_bringdown(eventhandler_tag eh_tag)
+{
+
+	fuse_ipc_destroy();
+	fuse_device_destroy();
+	mtx_destroy(&fuse_mtx);
+}
+
+static int
+fuse_loader(struct module *m, int what, void *arg)
+{
+	static eventhandler_tag eh_tag = NULL;
+	int err = 0;
+
+	switch (what) {
+	case MOD_LOAD:			/* kldload */
+		fuse_pbuf_freecnt = nswbuf / 2 + 1;
+		mtx_init(&fuse_mtx, "fuse_mtx", NULL, MTX_DEF);
+		err = fuse_device_init();
+		if (err) {
+			mtx_destroy(&fuse_mtx);
+			return (err);
+		}
+		fuse_ipc_init();
+
+		/* vfs_modevent ignores its first arg */
+		if ((err = vfs_modevent(NULL, what, &fuse_vfsconf)))
+			fuse_bringdown(eh_tag);
+		else
+			printf("fuse-freebsd: version %s, FUSE ABI %d.%d\n",
+			    FUSE_FREEBSD_VERSION,
+			    FUSE_KERNEL_VERSION, FUSE_KERNEL_MINOR_VERSION);
+
+		break;
+	case MOD_UNLOAD:
+		if ((err = vfs_modevent(NULL, what, &fuse_vfsconf)))
+			return (err);
+		fuse_bringdown(eh_tag);
+		break;
+	default:
+		return (EINVAL);
+	}
+
+	return (err);
+}
+
+/* Registering the module */
+
+static moduledata_t fuse_moddata = {
+	"fuse",
+	fuse_loader,
+	&fuse_vfsconf
+};
+
+DECLARE_MODULE(fuse, fuse_moddata, SI_SUB_VFS, SI_ORDER_MIDDLE);
+MODULE_VERSION(fuse, 1);