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, 451 insertions, 0 deletions

diff --git a/drivers/staging/lustre/lnet/lnet/lib-md.c b/drivers/staging/lustre/lnet/lnet/lib-md.c
new file mode 100644
index 000000000000..ae643f26933b
--- /dev/null
+++ b/drivers/staging/lustre/lnet/lnet/lib-md.c
@@ -0,0 +1,451 @@
+/*
+ * 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) 2003, 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.
+ *
+ * lnet/lnet/lib-md.c
+ *
+ * Memory Descriptor management routines
+ */
+
+#define DEBUG_SUBSYSTEM S_LNET
+
+#include <linux/lnet/lib-lnet.h>
+
+/* must be called with lnet_res_lock held */
+void
+lnet_md_unlink(lnet_libmd_t *md)
+{
+	if ((md->md_flags & LNET_MD_FLAG_ZOMBIE) == 0) {
+		/* first unlink attempt... */
+		lnet_me_t *me = md->md_me;
+
+		md->md_flags |= LNET_MD_FLAG_ZOMBIE;
+
+		/* Disassociate from ME (if any), and unlink it if it was created
+		 * with LNET_UNLINK */
+		if (me != NULL) {
+			/* detach MD from portal */
+			lnet_ptl_detach_md(me, md);
+			if (me->me_unlink == LNET_UNLINK)
+				lnet_me_unlink(me);
+		}
+
+		/* ensure all future handle lookups fail */
+		lnet_res_lh_invalidate(&md->md_lh);
+	}
+
+	if (md->md_refcount != 0) {
+		CDEBUG(D_NET, "Queueing unlink of md %p\n", md);
+		return;
+	}
+
+	CDEBUG(D_NET, "Unlinking md %p\n", md);
+
+	if (md->md_eq != NULL) {
+		int	cpt = lnet_cpt_of_cookie(md->md_lh.lh_cookie);
+
+		LASSERT(*md->md_eq->eq_refs[cpt] > 0);
+		(*md->md_eq->eq_refs[cpt])--;
+	}
+
+	LASSERT(!list_empty(&md->md_list));
+	list_del_init(&md->md_list);
+	lnet_md_free_locked(md);
+}
+
+static int
+lnet_md_build(lnet_libmd_t *lmd, lnet_md_t *umd, int unlink)
+{
+	int	  i;
+	unsigned int niov;
+	int	  total_length = 0;
+
+	lmd->md_me = NULL;
+	lmd->md_start = umd->start;
+	lmd->md_offset = 0;
+	lmd->md_max_size = umd->max_size;
+	lmd->md_options = umd->options;
+	lmd->md_user_ptr = umd->user_ptr;
+	lmd->md_eq = NULL;
+	lmd->md_threshold = umd->threshold;
+	lmd->md_refcount = 0;
+	lmd->md_flags = (unlink == LNET_UNLINK) ? LNET_MD_FLAG_AUTO_UNLINK : 0;
+
+	if ((umd->options & LNET_MD_IOVEC) != 0) {
+
+		if ((umd->options & LNET_MD_KIOV) != 0) /* Can't specify both */
+			return -EINVAL;
+
+		lmd->md_niov = niov = umd->length;
+		memcpy(lmd->md_iov.iov, umd->start,
+		       niov * sizeof (lmd->md_iov.iov[0]));
+
+		for (i = 0; i < (int)niov; i++) {
+			/* We take the base address on trust */
+			if (lmd->md_iov.iov[i].iov_len <= 0) /* invalid length */
+				return -EINVAL;
+
+			total_length += lmd->md_iov.iov[i].iov_len;
+		}
+
+		lmd->md_length = total_length;
+
+		if ((umd->options & LNET_MD_MAX_SIZE) != 0 && /* max size used */
+		    (umd->max_size < 0 ||
+		     umd->max_size > total_length)) // illegal max_size
+			return -EINVAL;
+
+	} else if ((umd->options & LNET_MD_KIOV) != 0) {
+		lmd->md_niov = niov = umd->length;
+		memcpy(lmd->md_iov.kiov, umd->start,
+		       niov * sizeof (lmd->md_iov.kiov[0]));
+
+		for (i = 0; i < (int)niov; i++) {
+			/* We take the page pointer on trust */
+			if (lmd->md_iov.kiov[i].kiov_offset +
+			    lmd->md_iov.kiov[i].kiov_len > PAGE_CACHE_SIZE )
+				return -EINVAL; /* invalid length */
+
+			total_length += lmd->md_iov.kiov[i].kiov_len;
+		}
+
+		lmd->md_length = total_length;
+
+		if ((umd->options & LNET_MD_MAX_SIZE) != 0 && /* max size used */
+		    (umd->max_size < 0 ||
+		     umd->max_size > total_length)) // illegal max_size
+			return -EINVAL;
+	} else {   /* contiguous */
+		lmd->md_length = umd->length;
+		lmd->md_niov = niov = 1;
+		lmd->md_iov.iov[0].iov_base = umd->start;
+		lmd->md_iov.iov[0].iov_len = umd->length;
+
+		if ((umd->options & LNET_MD_MAX_SIZE) != 0 && /* max size used */
+		    (umd->max_size < 0 ||
+		     umd->max_size > (int)umd->length)) // illegal max_size
+			return -EINVAL;
+	}
+
+	return 0;
+}
+
+/* must be called with resource lock held */
+static int
+lnet_md_link(lnet_libmd_t *md, lnet_handle_eq_t eq_handle, int cpt)
+{
+	struct lnet_res_container *container = the_lnet.ln_md_containers[cpt];
+
+	/* NB we are passed an allocated, but inactive md.
+	 * if we return success, caller may lnet_md_unlink() it.
+	 * otherwise caller may only lnet_md_free() it.
+	 */
+	/* This implementation doesn't know how to create START events or
+	 * disable END events.  Best to LASSERT our caller is compliant so
+	 * we find out quickly...  */
+	/*  TODO - reevaluate what should be here in light of
+	 * the removal of the start and end events
+	 * maybe there we shouldn't even allow LNET_EQ_NONE!)
+	 * LASSERT (eq == NULL);
+	 */
+	if (!LNetHandleIsInvalid(eq_handle)) {
+		md->md_eq = lnet_handle2eq(&eq_handle);
+
+		if (md->md_eq == NULL)
+			return -ENOENT;
+
+		(*md->md_eq->eq_refs[cpt])++;
+	}
+
+	lnet_res_lh_initialize(container, &md->md_lh);
+
+	LASSERT(list_empty(&md->md_list));
+	list_add(&md->md_list, &container->rec_active);
+
+	return 0;
+}
+
+/* must be called with lnet_res_lock held */
+void
+lnet_md_deconstruct(lnet_libmd_t *lmd, lnet_md_t *umd)
+{
+	/* NB this doesn't copy out all the iov entries so when a
+	 * discontiguous MD is copied out, the target gets to know the
+	 * original iov pointer (in start) and the number of entries it had
+	 * and that's all.
+	 */
+	umd->start = lmd->md_start;
+	umd->length = ((lmd->md_options & (LNET_MD_IOVEC | LNET_MD_KIOV)) == 0) ?
+		      lmd->md_length : lmd->md_niov;
+	umd->threshold = lmd->md_threshold;
+	umd->max_size = lmd->md_max_size;
+	umd->options = lmd->md_options;
+	umd->user_ptr = lmd->md_user_ptr;
+	lnet_eq2handle(&umd->eq_handle, lmd->md_eq);
+}
+
+int
+lnet_md_validate(lnet_md_t *umd)
+{
+	if (umd->start == NULL && umd->length != 0) {
+		CERROR("MD start pointer can not be NULL with length %u\n",
+		       umd->length);
+		return -EINVAL;
+	}
+
+	if ((umd->options & (LNET_MD_KIOV | LNET_MD_IOVEC)) != 0 &&
+	    umd->length > LNET_MAX_IOV) {
+		CERROR("Invalid option: too many fragments %u, %d max\n",
+		       umd->length, LNET_MAX_IOV);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/**
+ * Create a memory descriptor and attach it to a ME
+ *
+ * \param meh A handle for a ME to associate the new MD with.
+ * \param umd Provides initial values for the user-visible parts of a MD.
+ * Other than its use for initialization, there is no linkage between this
+ * structure and the MD maintained by the LNet.
+ * \param unlink A flag to indicate whether the MD is automatically unlinked
+ * when it becomes inactive, either because the operation threshold drops to
+ * zero or because the available memory becomes less than \a umd.max_size.
+ * (Note that the check for unlinking a MD only occurs after the completion
+ * of a successful operation on the MD.) The value LNET_UNLINK enables auto
+ * unlinking; the value LNET_RETAIN disables it.
+ * \param handle On successful returns, a handle to the newly created MD is
+ * saved here. This handle can be used later in LNetMDUnlink().
+ *
+ * \retval 0       On success.
+ * \retval -EINVAL If \a umd is not valid.
+ * \retval -ENOMEM If new MD cannot be allocated.
+ * \retval -ENOENT Either \a meh or \a umd.eq_handle does not point to a
+ * valid object. Note that it's OK to supply a NULL \a umd.eq_handle by
+ * calling LNetInvalidateHandle() on it.
+ * \retval -EBUSY  If the ME pointed to by \a meh is already associated with
+ * a MD.
+ */
+int
+LNetMDAttach(lnet_handle_me_t meh, lnet_md_t umd,
+	     lnet_unlink_t unlink, lnet_handle_md_t *handle)
+{
+	LIST_HEAD		(matches);
+	LIST_HEAD		(drops);
+	struct lnet_me		*me;
+	struct lnet_libmd	*md;
+	int			cpt;
+	int			rc;
+
+	LASSERT (the_lnet.ln_init);
+	LASSERT (the_lnet.ln_refcount > 0);
+
+	if (lnet_md_validate(&umd) != 0)
+		return -EINVAL;
+
+	if ((umd.options & (LNET_MD_OP_GET | LNET_MD_OP_PUT)) == 0) {
+		CERROR("Invalid option: no MD_OP set\n");
+		return -EINVAL;
+	}
+
+	md = lnet_md_alloc(&umd);
+	if (md == NULL)
+		return -ENOMEM;
+
+	rc = lnet_md_build(md, &umd, unlink);
+	cpt = lnet_cpt_of_cookie(meh.cookie);
+
+	lnet_res_lock(cpt);
+	if (rc != 0)
+		goto failed;
+
+	me = lnet_handle2me(&meh);
+	if (me == NULL)
+		rc = -ENOENT;
+	else if (me->me_md != NULL)
+		rc = -EBUSY;
+	else
+		rc = lnet_md_link(md, umd.eq_handle, cpt);
+
+	if (rc != 0)
+		goto failed;
+
+	/* attach this MD to portal of ME and check if it matches any
+	 * blocked msgs on this portal */
+	lnet_ptl_attach_md(me, md, &matches, &drops);
+
+	lnet_md2handle(handle, md);
+
+	lnet_res_unlock(cpt);
+
+	lnet_drop_delayed_msg_list(&drops, "Bad match");
+	lnet_recv_delayed_msg_list(&matches);
+
+	return 0;
+
+ failed:
+	lnet_md_free_locked(md);
+
+	lnet_res_unlock(cpt);
+	return rc;
+}
+EXPORT_SYMBOL(LNetMDAttach);
+
+/**
+ * Create a "free floating" memory descriptor - a MD that is not associated
+ * with a ME. Such MDs are usually used in LNetPut() and LNetGet() operations.
+ *
+ * \param umd,unlink See the discussion for LNetMDAttach().
+ * \param handle On successful returns, a handle to the newly created MD is
+ * saved here. This handle can be used later in LNetMDUnlink(), LNetPut(),
+ * and LNetGet() operations.
+ *
+ * \retval 0       On success.
+ * \retval -EINVAL If \a umd is not valid.
+ * \retval -ENOMEM If new MD cannot be allocated.
+ * \retval -ENOENT \a umd.eq_handle does not point to a valid EQ. Note that
+ * it's OK to supply a NULL \a umd.eq_handle by calling
+ * LNetInvalidateHandle() on it.
+ */
+int
+LNetMDBind(lnet_md_t umd, lnet_unlink_t unlink, lnet_handle_md_t *handle)
+{
+	lnet_libmd_t	*md;
+	int		cpt;
+	int		rc;
+
+	LASSERT (the_lnet.ln_init);
+	LASSERT (the_lnet.ln_refcount > 0);
+
+	if (lnet_md_validate(&umd) != 0)
+		return -EINVAL;
+
+	if ((umd.options & (LNET_MD_OP_GET | LNET_MD_OP_PUT)) != 0) {
+		CERROR("Invalid option: GET|PUT illegal on active MDs\n");
+		return -EINVAL;
+	}
+
+	md = lnet_md_alloc(&umd);
+	if (md == NULL)
+		return -ENOMEM;
+
+	rc = lnet_md_build(md, &umd, unlink);
+
+	cpt = lnet_res_lock_current();
+	if (rc != 0)
+		goto failed;
+
+	rc = lnet_md_link(md, umd.eq_handle, cpt);
+	if (rc != 0)
+		goto failed;
+
+	lnet_md2handle(handle, md);
+
+	lnet_res_unlock(cpt);
+	return 0;
+
+ failed:
+	lnet_md_free_locked(md);
+
+	lnet_res_unlock(cpt);
+	return rc;
+}
+EXPORT_SYMBOL(LNetMDBind);
+
+/**
+ * Unlink the memory descriptor from any ME it may be linked to and release
+ * the internal resources associated with it.
+ *
+ * This function does not free the memory region associated with the MD;
+ * i.e., the memory the user allocated for this MD. If the ME associated with
+ * this MD is not NULL and was created with auto unlink enabled, the ME is
+ * unlinked as well (see LNetMEAttach()).
+ *
+ * Explicitly unlinking a MD via this function call has the same behavior as
+ * a MD that has been automatically unlinked, except that no LNET_EVENT_UNLINK
+ * is generated in the latter case.
+ *
+ * An unlinked event can be reported in two ways:
+ * - If there's no pending operations on the MD, it's unlinked immediately
+ *   and an LNET_EVENT_UNLINK event is logged before this function returns.
+ * - Otherwise, the MD is only marked for deletion when this function
+ *   returns, and the unlinked event will be piggybacked on the event of
+ *   the completion of the last operation by setting the unlinked field of
+ *   the event. No dedicated LNET_EVENT_UNLINK event is generated.
+ *
+ * Note that in both cases the unlinked field of the event is always set; no
+ * more event will happen on the MD after such an event is logged.
+ *
+ * \param mdh A handle for the MD to be unlinked.
+ *
+ * \retval 0       On success.
+ * \retval -ENOENT If \a mdh does not point to a valid MD object.
+ */
+int
+LNetMDUnlink (lnet_handle_md_t mdh)
+{
+	lnet_event_t	ev;
+	lnet_libmd_t	*md;
+	int		cpt;
+
+	LASSERT(the_lnet.ln_init);
+	LASSERT(the_lnet.ln_refcount > 0);
+
+	cpt = lnet_cpt_of_cookie(mdh.cookie);
+	lnet_res_lock(cpt);
+
+	md = lnet_handle2md(&mdh);
+	if (md == NULL) {
+		lnet_res_unlock(cpt);
+		return -ENOENT;
+	}
+
+	/* If the MD is busy, lnet_md_unlink just marks it for deletion, and
+	 * when the NAL is done, the completion event flags that the MD was
+	 * unlinked.  Otherwise, we enqueue an event now... */
+
+	if (md->md_eq != NULL &&
+	    md->md_refcount == 0) {
+		lnet_build_unlink_event(md, &ev);
+		lnet_eq_enqueue_event(md->md_eq, &ev);
+	}
+
+	lnet_md_unlink(md);
+
+	lnet_res_unlock(cpt);
+	return 0;
+}
+EXPORT_SYMBOL(LNetMDUnlink);