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, 218 insertions, 0 deletions

diff --git a/drivers/staging/lustre/lustre/lov/lov_merge.c b/drivers/staging/lustre/lustre/lov/lov_merge.c
new file mode 100644
index 000000000000..ddbac1220263
--- /dev/null
+++ b/drivers/staging/lustre/lustre/lov/lov_merge.c
@@ -0,0 +1,218 @@
+/*
+ * 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) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Use is subject to license terms.
+ *
+ * Copyright (c) 2012, Intel Corporation.
+ */
+/*
+ * This file is part of Lustre, http://www.lustre.org/
+ * Lustre is a trademark of Sun Microsystems, Inc.
+ */
+
+#define DEBUG_SUBSYSTEM S_LOV
+
+#include <linux/libcfs/libcfs.h>
+
+#include <obd_class.h>
+#include <obd_lov.h>
+
+#include "lov_internal.h"
+
+/** Merge the lock value block(&lvb) attributes and KMS from each of the
+ * stripes in a file into a single lvb. It is expected that the caller
+ * initializes the current atime, mtime, ctime to avoid regressing a more
+ * uptodate time on the local client.
+ */
+int lov_merge_lvb_kms(struct lov_stripe_md *lsm,
+		      struct ost_lvb *lvb, __u64 *kms_place)
+{
+	__u64 size = 0;
+	__u64 kms = 0;
+	__u64 blocks = 0;
+	obd_time current_mtime = lvb->lvb_mtime;
+	obd_time current_atime = lvb->lvb_atime;
+	obd_time current_ctime = lvb->lvb_ctime;
+	int i;
+	int rc = 0;
+
+	LASSERT(spin_is_locked(&lsm->lsm_lock));
+	LASSERT(lsm->lsm_lock_owner == current_pid());
+
+	CDEBUG(D_INODE, "MDT ID "DOSTID" initial value: s="LPU64" m="LPU64
+	       " a="LPU64" c="LPU64" b="LPU64"\n", POSTID(&lsm->lsm_oi),
+	       lvb->lvb_size, lvb->lvb_mtime, lvb->lvb_atime, lvb->lvb_ctime,
+	       lvb->lvb_blocks);
+	for (i = 0; i < lsm->lsm_stripe_count; i++) {
+		struct lov_oinfo *loi = lsm->lsm_oinfo[i];
+		obd_size lov_size, tmpsize;
+
+		if (OST_LVB_IS_ERR(loi->loi_lvb.lvb_blocks)) {
+			rc = OST_LVB_GET_ERR(loi->loi_lvb.lvb_blocks);
+			continue;
+		}
+
+		tmpsize = loi->loi_kms;
+		lov_size = lov_stripe_size(lsm, tmpsize, i);
+		if (lov_size > kms)
+			kms = lov_size;
+
+		if (loi->loi_lvb.lvb_size > tmpsize)
+			tmpsize = loi->loi_lvb.lvb_size;
+
+		lov_size = lov_stripe_size(lsm, tmpsize, i);
+		if (lov_size > size)
+			size = lov_size;
+		/* merge blocks, mtime, atime */
+		blocks += loi->loi_lvb.lvb_blocks;
+		if (loi->loi_lvb.lvb_mtime > current_mtime)
+			current_mtime = loi->loi_lvb.lvb_mtime;
+		if (loi->loi_lvb.lvb_atime > current_atime)
+			current_atime = loi->loi_lvb.lvb_atime;
+		if (loi->loi_lvb.lvb_ctime > current_ctime)
+			current_ctime = loi->loi_lvb.lvb_ctime;
+
+		CDEBUG(D_INODE, "MDT ID "DOSTID" on OST[%u]: s="LPU64" m="LPU64
+		       " a="LPU64" c="LPU64" b="LPU64"\n", POSTID(&lsm->lsm_oi),
+		       loi->loi_ost_idx, loi->loi_lvb.lvb_size,
+		       loi->loi_lvb.lvb_mtime, loi->loi_lvb.lvb_atime,
+		       loi->loi_lvb.lvb_ctime, loi->loi_lvb.lvb_blocks);
+	}
+
+	*kms_place = kms;
+	lvb->lvb_size = size;
+	lvb->lvb_blocks = blocks;
+	lvb->lvb_mtime = current_mtime;
+	lvb->lvb_atime = current_atime;
+	lvb->lvb_ctime = current_ctime;
+	RETURN(rc);
+}
+
+/** Merge the lock value block(&lvb) attributes from each of the stripes in a
+ * file into a single lvb. It is expected that the caller initializes the
+ * current atime, mtime, ctime to avoid regressing a more uptodate time on
+ * the local client.
+ *
+ * If \a kms_only is set then we do not consider the recently seen size (rss)
+ * when updating the known minimum size (kms).  Even when merging RSS, we will
+ * take the KMS value if it's larger.  This prevents getattr from stomping on
+ * dirty cached pages which extend the file size. */
+int lov_merge_lvb(struct obd_export *exp,
+		  struct lov_stripe_md *lsm, struct ost_lvb *lvb, int kms_only)
+{
+	int   rc;
+	__u64 kms;
+
+	ENTRY;
+	lov_stripe_lock(lsm);
+	rc = lov_merge_lvb_kms(lsm, lvb, &kms);
+	lov_stripe_unlock(lsm);
+	if (kms_only)
+		lvb->lvb_size = kms;
+
+	CDEBUG(D_INODE, "merged for ID "DOSTID" s="LPU64" m="LPU64" a="LPU64
+	       " c="LPU64" b="LPU64"\n", POSTID(&lsm->lsm_oi), lvb->lvb_size,
+	       lvb->lvb_mtime, lvb->lvb_atime, lvb->lvb_ctime, lvb->lvb_blocks);
+	RETURN(rc);
+}
+
+/* Must be called under the lov_stripe_lock() */
+int lov_adjust_kms(struct obd_export *exp, struct lov_stripe_md *lsm,
+		   obd_off size, int shrink)
+{
+	struct lov_oinfo *loi;
+	int stripe = 0;
+	__u64 kms;
+	ENTRY;
+
+	LASSERT(spin_is_locked(&lsm->lsm_lock));
+	LASSERT(lsm->lsm_lock_owner == current_pid());
+
+	if (shrink) {
+		for (; stripe < lsm->lsm_stripe_count; stripe++) {
+			struct lov_oinfo *loi = lsm->lsm_oinfo[stripe];
+			kms = lov_size_to_stripe(lsm, size, stripe);
+			CDEBUG(D_INODE,
+			       "stripe %d KMS %sing "LPU64"->"LPU64"\n",
+			       stripe, kms > loi->loi_kms ? "increas":"shrink",
+			       loi->loi_kms, kms);
+			loi_kms_set(loi, loi->loi_lvb.lvb_size = kms);
+		}
+		RETURN(0);
+	}
+
+	if (size > 0)
+		stripe = lov_stripe_number(lsm, size - 1);
+	kms = lov_size_to_stripe(lsm, size, stripe);
+	loi = lsm->lsm_oinfo[stripe];
+
+	CDEBUG(D_INODE, "stripe %d KMS %sincreasing "LPU64"->"LPU64"\n",
+	       stripe, kms > loi->loi_kms ? "" : "not ", loi->loi_kms, kms);
+	if (kms > loi->loi_kms)
+		loi_kms_set(loi, kms);
+
+	RETURN(0);
+}
+
+void lov_merge_attrs(struct obdo *tgt, struct obdo *src, obd_valid valid,
+		     struct lov_stripe_md *lsm, int stripeno, int *set)
+{
+	valid &= src->o_valid;
+
+	if (*set) {
+		if (valid & OBD_MD_FLSIZE) {
+			/* this handles sparse files properly */
+			obd_size lov_size;
+
+			lov_size = lov_stripe_size(lsm, src->o_size, stripeno);
+			if (lov_size > tgt->o_size)
+				tgt->o_size = lov_size;
+		}
+		if (valid & OBD_MD_FLBLOCKS)
+			tgt->o_blocks += src->o_blocks;
+		if (valid & OBD_MD_FLBLKSZ)
+			tgt->o_blksize += src->o_blksize;
+		if (valid & OBD_MD_FLCTIME && tgt->o_ctime < src->o_ctime)
+			tgt->o_ctime = src->o_ctime;
+		if (valid & OBD_MD_FLMTIME && tgt->o_mtime < src->o_mtime)
+			tgt->o_mtime = src->o_mtime;
+		if (valid & OBD_MD_FLDATAVERSION)
+			tgt->o_data_version += src->o_data_version;
+	} else {
+		memcpy(tgt, src, sizeof(*tgt));
+		tgt->o_oi = lsm->lsm_oi;
+		if (valid & OBD_MD_FLSIZE)
+			tgt->o_size = lov_stripe_size(lsm, src->o_size,
+						      stripeno);
+	}
+
+	/* data_version needs to be valid on all stripes to be correct! */
+	if (!(valid & OBD_MD_FLDATAVERSION))
+		tgt->o_valid &= ~OBD_MD_FLDATAVERSION;
+
+	*set += 1;
+}