staging: add Lustre file system client support

Lustre is the most deployed distributed file system
in the HPC (High Performance Computing) world. The patch
adds its client side support.

The code is not very clean and needs to live in drivers/staging
for some time for continuing cleanup work. See
drivers/staging/lustre/TODO for details.

The code is based on Lustre master commit faefbfc04

commit faefbfc0460bc00f2ee4c1c1c86aa1e39b9eea49
Author: Alex Zhuravlev <alexey.zhuravlev@intel.com>
Date:   Tue Apr 30 23:05:21 2013 +0400

    LU-3244 utils: tunefs.lustre should preserve virgin label

Plus a few under-review patches on Whamcloud gerrit:
3.8 kernel support:
http://review.whamcloud.com/#change,5973
http://review.whamcloud.com/#change,5974
http://review.whamcloud.com/#change,5768
http://review.whamcloud.com/#change,5781
http://review.whamcloud.com/#change,5763
http://review.whamcloud.com/#change,5613
http://review.whamcloud.com/#change,5655

3.9 kernel support:
http://review.whamcloud.com/#change,5898
http://review.whamcloud.com/#change,5899

Kconfig/Kbuild:
http://review.whamcloud.com/#change,4646
http://review.whamcloud.com/#change,4644

libcfs cleanup:
http://review.whamcloud.com/#change,2831
http://review.whamcloud.com/#change,4775
http://review.whamcloud.com/#change,4776
http://review.whamcloud.com/#change,4777
http://review.whamcloud.com/#change,4778
http://review.whamcloud.com/#change,4779
http://review.whamcloud.com/#change,4780

All starting/trailing whitespaces are removed, to match kernel
coding style. Also ran scripts/cleanfile on all lustre source files.

[maked the Kconfig depend on BROKEN as the recent procfs changes causes
this to fail - gregkh]

Signed-off-by: Peng Tao <tao.peng@emc.com>
Signed-off-by: Andreas Dilger <andreas.dilger@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 235 insertions, 0 deletions

diff --git a/drivers/staging/lustre/lustre/lov/lov_page.c b/drivers/staging/lustre/lustre/lov/lov_page.c
new file mode 100644
index 000000000000..65790d684720
--- /dev/null
+++ b/drivers/staging/lustre/lustre/lov/lov_page.c
@@ -0,0 +1,235 @@
+/*
+ * GPL HEADER START
+ *
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 only,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License version 2 for more details (a copy is included
+ * in the LICENSE file that accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License
+ * version 2 along with this program; If not, see
+ * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ *
+ * GPL HEADER END
+ */
+/*
+ * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Use is subject to license terms.
+ *
+ * Copyright (c) 2011, 2012, Intel Corporation.
+ */
+/*
+ * This file is part of Lustre, http://www.lustre.org/
+ * Lustre is a trademark of Sun Microsystems, Inc.
+ *
+ * Implementation of cl_page for LOV layer.
+ *
+ *   Author: Nikita Danilov <nikita.danilov@sun.com>
+ */
+
+#define DEBUG_SUBSYSTEM S_LOV
+
+#include "lov_cl_internal.h"
+
+/** \addtogroup lov
+ *  @{
+ */
+
+/*****************************************************************************
+ *
+ * Lov page operations.
+ *
+ */
+
+static int lov_page_invariant(const struct cl_page_slice *slice)
+{
+	const struct cl_page  *page = slice->cpl_page;
+	const struct cl_page  *sub  = lov_sub_page(slice);
+
+	return ergo(sub != NULL,
+		    page->cp_child == sub &&
+		    sub->cp_parent == page &&
+		    page->cp_state == sub->cp_state);
+}
+
+static void lov_page_fini(const struct lu_env *env,
+			  struct cl_page_slice *slice)
+{
+	struct cl_page  *sub = lov_sub_page(slice);
+
+	LINVRNT(lov_page_invariant(slice));
+	ENTRY;
+
+	if (sub != NULL) {
+		LASSERT(sub->cp_state == CPS_FREEING);
+		lu_ref_del(&sub->cp_reference, "lov", sub->cp_parent);
+		sub->cp_parent = NULL;
+		slice->cpl_page->cp_child = NULL;
+		cl_page_put(env, sub);
+	}
+	EXIT;
+}
+
+static int lov_page_own(const struct lu_env *env,
+			const struct cl_page_slice *slice, struct cl_io *io,
+			int nonblock)
+{
+	struct lov_io     *lio = lov_env_io(env);
+	struct lov_io_sub *sub;
+
+	LINVRNT(lov_page_invariant(slice));
+	LINVRNT(!cl2lov_page(slice)->lps_invalid);
+	ENTRY;
+
+	sub = lov_page_subio(env, lio, slice);
+	if (!IS_ERR(sub)) {
+		lov_sub_page(slice)->cp_owner = sub->sub_io;
+		lov_sub_put(sub);
+	} else
+		LBUG(); /* Arrgh */
+	RETURN(0);
+}
+
+static void lov_page_assume(const struct lu_env *env,
+			    const struct cl_page_slice *slice, struct cl_io *io)
+{
+	lov_page_own(env, slice, io, 0);
+}
+
+static int lov_page_cache_add(const struct lu_env *env,
+			      const struct cl_page_slice *slice,
+			      struct cl_io *io)
+{
+	struct lov_io     *lio = lov_env_io(env);
+	struct lov_io_sub *sub;
+	int rc = 0;
+
+	LINVRNT(lov_page_invariant(slice));
+	LINVRNT(!cl2lov_page(slice)->lps_invalid);
+	ENTRY;
+
+	sub = lov_page_subio(env, lio, slice);
+	if (!IS_ERR(sub)) {
+		rc = cl_page_cache_add(sub->sub_env, sub->sub_io,
+				       slice->cpl_page->cp_child, CRT_WRITE);
+		lov_sub_put(sub);
+	} else {
+		rc = PTR_ERR(sub);
+		CL_PAGE_DEBUG(D_ERROR, env, slice->cpl_page, "rc = %d\n", rc);
+	}
+	RETURN(rc);
+}
+
+static int lov_page_print(const struct lu_env *env,
+			  const struct cl_page_slice *slice,
+			  void *cookie, lu_printer_t printer)
+{
+	struct lov_page *lp = cl2lov_page(slice);
+
+	return (*printer)(env, cookie, LUSTRE_LOV_NAME"-page@%p\n", lp);
+}
+
+static const struct cl_page_operations lov_page_ops = {
+	.cpo_fini   = lov_page_fini,
+	.cpo_own    = lov_page_own,
+	.cpo_assume = lov_page_assume,
+	.io = {
+		[CRT_WRITE] = {
+			.cpo_cache_add = lov_page_cache_add
+		}
+	},
+	.cpo_print  = lov_page_print
+};
+
+static void lov_empty_page_fini(const struct lu_env *env,
+				struct cl_page_slice *slice)
+{
+	LASSERT(slice->cpl_page->cp_child == NULL);
+}
+
+int lov_page_init_raid0(const struct lu_env *env, struct cl_object *obj,
+			struct cl_page *page, struct page *vmpage)
+{
+	struct lov_object *loo = cl2lov(obj);
+	struct lov_layout_raid0 *r0 = lov_r0(loo);
+	struct lov_io     *lio = lov_env_io(env);
+	struct cl_page    *subpage;
+	struct cl_object  *subobj;
+	struct lov_io_sub *sub;
+	struct lov_page   *lpg = cl_object_page_slice(obj, page);
+	loff_t	     offset;
+	obd_off	    suboff;
+	int		stripe;
+	int		rc;
+	ENTRY;
+
+	offset = cl_offset(obj, page->cp_index);
+	stripe = lov_stripe_number(loo->lo_lsm, offset);
+	LASSERT(stripe < r0->lo_nr);
+	rc = lov_stripe_offset(loo->lo_lsm, offset, stripe,
+				   &suboff);
+	LASSERT(rc == 0);
+
+	lpg->lps_invalid = 1;
+	cl_page_slice_add(page, &lpg->lps_cl, obj, &lov_page_ops);
+
+	sub = lov_sub_get(env, lio, stripe);
+	if (IS_ERR(sub))
+		GOTO(out, rc = PTR_ERR(sub));
+
+	subobj = lovsub2cl(r0->lo_sub[stripe]);
+	subpage = cl_page_find_sub(sub->sub_env, subobj,
+				   cl_index(subobj, suboff), vmpage, page);
+	lov_sub_put(sub);
+	if (IS_ERR(subpage))
+		GOTO(out, rc = PTR_ERR(subpage));
+
+	if (likely(subpage->cp_parent == page)) {
+		lu_ref_add(&subpage->cp_reference, "lov", page);
+		lpg->lps_invalid = 0;
+		rc = 0;
+	} else {
+		CL_PAGE_DEBUG(D_ERROR, env, page, "parent page\n");
+		CL_PAGE_DEBUG(D_ERROR, env, subpage, "child page\n");
+		LASSERT(0);
+	}
+
+	EXIT;
+out:
+	return rc;
+}
+
+
+static const struct cl_page_operations lov_empty_page_ops = {
+	.cpo_fini   = lov_empty_page_fini,
+	.cpo_print  = lov_page_print
+};
+
+int lov_page_init_empty(const struct lu_env *env, struct cl_object *obj,
+			struct cl_page *page, struct page *vmpage)
+{
+	struct lov_page *lpg = cl_object_page_slice(obj, page);
+	void *addr;
+	ENTRY;
+
+	cl_page_slice_add(page, &lpg->lps_cl, obj, &lov_empty_page_ops);
+	addr = kmap(vmpage);
+	memset(addr, 0, cl_page_size(obj));
+	kunmap(vmpage);
+	cl_page_export(env, page, 1);
+	RETURN(0);
+}
+
+
+/** @} lov */