1 files changed, 519 insertions, 0 deletions
diff --git a/drivers/staging/lustre/lustre/fld/fld_request.c b/drivers/staging/lustre/lustre/fld/fld_request.c
new file mode 100644
index 000000000000..e9f07398b68a
--- /dev/null
+++ b/drivers/staging/lustre/lustre/fld/fld_request.c
@@ -0,0 +1,519 @@
+/*
+ * 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) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Use is subject to license terms.
+ *
+ * Copyright (c) 2011, 2013, Intel Corporation.
+ */
+/*
+ * This file is part of Lustre, http://www.lustre.org/
+ * Lustre is a trademark of Sun Microsystems, Inc.
+ *
+ * lustre/fld/fld_request.c
+ *
+ * FLD (Fids Location Database)
+ *
+ * Author: Yury Umanets <umka@clusterfs.com>
+ */
+
+#define DEBUG_SUBSYSTEM S_FLD
+
+# include <linux/libcfs/libcfs.h>
+# include <linux/module.h>
+# include <linux/jbd.h>
+# include <asm/div64.h>
+
+#include <obd.h>
+#include <obd_class.h>
+#include <lustre_ver.h>
+#include <obd_support.h>
+#include <lprocfs_status.h>
+
+#include <dt_object.h>
+#include <md_object.h>
+#include <lustre_req_layout.h>
+#include <lustre_fld.h>
+#include <lustre_mdc.h>
+#include "fld_internal.h"
+
+/* TODO: these 3 functions are copies of flow-control code from mdc_lib.c
+ * It should be common thing. The same about mdc RPC lock */
+static int fld_req_avail(struct client_obd *cli, struct mdc_cache_waiter *mcw)
+{
+	int rc;
+	ENTRY;
+	client_obd_list_lock(&cli->cl_loi_list_lock);
+	rc = list_empty(&mcw->mcw_entry);
+	client_obd_list_unlock(&cli->cl_loi_list_lock);
+	RETURN(rc);
+};
+
+static void fld_enter_request(struct client_obd *cli)
+{
+	struct mdc_cache_waiter mcw;
+	struct l_wait_info lwi = { 0 };
+
+	client_obd_list_lock(&cli->cl_loi_list_lock);
+	if (cli->cl_r_in_flight >= cli->cl_max_rpcs_in_flight) {
+		list_add_tail(&mcw.mcw_entry, &cli->cl_cache_waiters);
+		init_waitqueue_head(&mcw.mcw_waitq);
+		client_obd_list_unlock(&cli->cl_loi_list_lock);
+		l_wait_event(mcw.mcw_waitq, fld_req_avail(cli, &mcw), &lwi);
+	} else {
+		cli->cl_r_in_flight++;
+		client_obd_list_unlock(&cli->cl_loi_list_lock);
+	}
+}
+
+static void fld_exit_request(struct client_obd *cli)
+{
+	struct list_head *l, *tmp;
+	struct mdc_cache_waiter *mcw;
+
+	client_obd_list_lock(&cli->cl_loi_list_lock);
+	cli->cl_r_in_flight--;
+	list_for_each_safe(l, tmp, &cli->cl_cache_waiters) {
+
+		if (cli->cl_r_in_flight >= cli->cl_max_rpcs_in_flight) {
+			/* No free request slots anymore */
+			break;
+		}
+
+		mcw = list_entry(l, struct mdc_cache_waiter, mcw_entry);
+		list_del_init(&mcw->mcw_entry);
+		cli->cl_r_in_flight++;
+		wake_up(&mcw->mcw_waitq);
+	}
+	client_obd_list_unlock(&cli->cl_loi_list_lock);
+}
+
+static int fld_rrb_hash(struct lu_client_fld *fld,
+			seqno_t seq)
+{
+	LASSERT(fld->lcf_count > 0);
+	return do_div(seq, fld->lcf_count);
+}
+
+static struct lu_fld_target *
+fld_rrb_scan(struct lu_client_fld *fld, seqno_t seq)
+{
+	struct lu_fld_target *target;
+	int hash;
+	ENTRY;
+
+	/* Because almost all of special sequence located in MDT0,
+	 * it should go to index 0 directly, instead of calculating
+	 * hash again, and also if other MDTs is not being connected,
+	 * the fld lookup requests(for seq on MDT0) should not be
+	 * blocked because of other MDTs */
+	if (fid_seq_is_norm(seq))
+		hash = fld_rrb_hash(fld, seq);
+	else
+		hash = 0;
+
+	list_for_each_entry(target, &fld->lcf_targets, ft_chain) {
+		if (target->ft_idx == hash)
+			RETURN(target);
+	}
+
+	CERROR("%s: Can't find target by hash %d (seq "LPX64"). "
+	       "Targets (%d):\n", fld->lcf_name, hash, seq,
+	       fld->lcf_count);
+
+	list_for_each_entry(target, &fld->lcf_targets, ft_chain) {
+		const char *srv_name = target->ft_srv != NULL  ?
+			target->ft_srv->lsf_name : "<null>";
+		const char *exp_name = target->ft_exp != NULL ?
+			(char *)target->ft_exp->exp_obd->obd_uuid.uuid :
+			"<null>";
+
+		CERROR("  exp: 0x%p (%s), srv: 0x%p (%s), idx: "LPU64"\n",
+		       target->ft_exp, exp_name, target->ft_srv,
+		       srv_name, target->ft_idx);
+	}
+
+	/*
+	 * If target is not found, there is logical error anyway, so here is
+	 * LBUG() to catch this situation.
+	 */
+	LBUG();
+	RETURN(NULL);
+}
+
+struct lu_fld_hash fld_hash[] = {
+	{
+		.fh_name = "RRB",
+		.fh_hash_func = fld_rrb_hash,
+		.fh_scan_func = fld_rrb_scan
+	},
+	{
+		0,
+	}
+};
+
+static struct lu_fld_target *
+fld_client_get_target(struct lu_client_fld *fld, seqno_t seq)
+{
+	struct lu_fld_target *target;
+	ENTRY;
+
+	LASSERT(fld->lcf_hash != NULL);
+
+	spin_lock(&fld->lcf_lock);
+	target = fld->lcf_hash->fh_scan_func(fld, seq);
+	spin_unlock(&fld->lcf_lock);
+
+	if (target != NULL) {
+		CDEBUG(D_INFO, "%s: Found target (idx "LPU64
+		       ") by seq "LPX64"\n", fld->lcf_name,
+		       target->ft_idx, seq);
+	}
+
+	RETURN(target);
+}
+
+/*
+ * Add export to FLD. This is usually done by CMM and LMV as they are main users
+ * of FLD module.
+ */
+int fld_client_add_target(struct lu_client_fld *fld,
+			  struct lu_fld_target *tar)
+{
+	const char *name;
+	struct lu_fld_target *target, *tmp;
+	ENTRY;
+
+	LASSERT(tar != NULL);
+	name = fld_target_name(tar);
+	LASSERT(name != NULL);
+	LASSERT(tar->ft_srv != NULL || tar->ft_exp != NULL);
+
+	if (fld->lcf_flags != LUSTRE_FLD_INIT) {
+		CERROR("%s: Attempt to add target %s (idx "LPU64") "
+		       "on fly - skip it\n", fld->lcf_name, name,
+		       tar->ft_idx);
+		RETURN(0);
+	} else {
+		CDEBUG(D_INFO, "%s: Adding target %s (idx "
+		       LPU64")\n", fld->lcf_name, name, tar->ft_idx);
+	}
+
+	OBD_ALLOC_PTR(target);
+	if (target == NULL)
+		RETURN(-ENOMEM);
+
+	spin_lock(&fld->lcf_lock);
+	list_for_each_entry(tmp, &fld->lcf_targets, ft_chain) {
+		if (tmp->ft_idx == tar->ft_idx) {
+			spin_unlock(&fld->lcf_lock);
+			OBD_FREE_PTR(target);
+			CERROR("Target %s exists in FLD and known as %s:#"LPU64"\n",
+			       name, fld_target_name(tmp), tmp->ft_idx);
+			RETURN(-EEXIST);
+		}
+	}
+
+	target->ft_exp = tar->ft_exp;
+	if (target->ft_exp != NULL)
+		class_export_get(target->ft_exp);
+	target->ft_srv = tar->ft_srv;
+	target->ft_idx = tar->ft_idx;
+
+	list_add_tail(&target->ft_chain,
+			  &fld->lcf_targets);
+
+	fld->lcf_count++;
+	spin_unlock(&fld->lcf_lock);
+
+	RETURN(0);
+}
+EXPORT_SYMBOL(fld_client_add_target);
+
+/* Remove export from FLD */
+int fld_client_del_target(struct lu_client_fld *fld, __u64 idx)
+{
+	struct lu_fld_target *target, *tmp;
+	ENTRY;
+
+	spin_lock(&fld->lcf_lock);
+	list_for_each_entry_safe(target, tmp,
+				     &fld->lcf_targets, ft_chain) {
+		if (target->ft_idx == idx) {
+			fld->lcf_count--;
+			list_del(&target->ft_chain);
+			spin_unlock(&fld->lcf_lock);
+
+			if (target->ft_exp != NULL)
+				class_export_put(target->ft_exp);
+
+			OBD_FREE_PTR(target);
+			RETURN(0);
+		}
+	}
+	spin_unlock(&fld->lcf_lock);
+	RETURN(-ENOENT);
+}
+EXPORT_SYMBOL(fld_client_del_target);
+
+#ifdef LPROCFS
+static int fld_client_proc_init(struct lu_client_fld *fld)
+{
+	int rc;
+	ENTRY;
+
+	fld->lcf_proc_dir = lprocfs_register(fld->lcf_name,
+					     fld_type_proc_dir,
+					     NULL, NULL);
+
+	if (IS_ERR(fld->lcf_proc_dir)) {
+		CERROR("%s: LProcFS failed in fld-init\n",
+		       fld->lcf_name);
+		rc = PTR_ERR(fld->lcf_proc_dir);
+		RETURN(rc);
+	}
+
+	rc = lprocfs_add_vars(fld->lcf_proc_dir,
+			      fld_client_proc_list, fld);
+	if (rc) {
+		CERROR("%s: Can't init FLD proc, rc %d\n",
+		       fld->lcf_name, rc);
+		GOTO(out_cleanup, rc);
+	}
+
+	RETURN(0);
+
+out_cleanup:
+	fld_client_proc_fini(fld);
+	return rc;
+}
+
+void fld_client_proc_fini(struct lu_client_fld *fld)
+{
+	ENTRY;
+	if (fld->lcf_proc_dir) {
+		if (!IS_ERR(fld->lcf_proc_dir))
+			lprocfs_remove(&fld->lcf_proc_dir);
+		fld->lcf_proc_dir = NULL;
+	}
+	EXIT;
+}
+#else
+static int fld_client_proc_init(struct lu_client_fld *fld)
+{
+	return 0;
+}
+
+void fld_client_proc_fini(struct lu_client_fld *fld)
+{
+	return;
+}
+#endif
+
+EXPORT_SYMBOL(fld_client_proc_fini);
+
+static inline int hash_is_sane(int hash)
+{
+	return (hash >= 0 && hash < ARRAY_SIZE(fld_hash));
+}
+
+int fld_client_init(struct lu_client_fld *fld,
+		    const char *prefix, int hash)
+{
+	int cache_size, cache_threshold;
+	int rc;
+	ENTRY;
+
+	LASSERT(fld != NULL);
+
+	snprintf(fld->lcf_name, sizeof(fld->lcf_name),
+		 "cli-%s", prefix);
+
+	if (!hash_is_sane(hash)) {
+		CERROR("%s: Wrong hash function %#x\n",
+		       fld->lcf_name, hash);
+		RETURN(-EINVAL);
+	}
+
+	fld->lcf_count = 0;
+	spin_lock_init(&fld->lcf_lock);
+	fld->lcf_hash = &fld_hash[hash];
+	fld->lcf_flags = LUSTRE_FLD_INIT;
+	INIT_LIST_HEAD(&fld->lcf_targets);
+
+	cache_size = FLD_CLIENT_CACHE_SIZE /
+		sizeof(struct fld_cache_entry);
+
+	cache_threshold = cache_size *
+		FLD_CLIENT_CACHE_THRESHOLD / 100;
+
+	fld->lcf_cache = fld_cache_init(fld->lcf_name,
+					cache_size, cache_threshold);
+	if (IS_ERR(fld->lcf_cache)) {
+		rc = PTR_ERR(fld->lcf_cache);
+		fld->lcf_cache = NULL;
+		GOTO(out, rc);
+	}
+
+	rc = fld_client_proc_init(fld);
+	if (rc)
+		GOTO(out, rc);
+	EXIT;
+out:
+	if (rc)
+		fld_client_fini(fld);
+	else
+		CDEBUG(D_INFO, "%s: Using \"%s\" hash\n",
+		       fld->lcf_name, fld->lcf_hash->fh_name);
+	return rc;
+}
+EXPORT_SYMBOL(fld_client_init);
+
+void fld_client_fini(struct lu_client_fld *fld)
+{
+	struct lu_fld_target *target, *tmp;
+	ENTRY;
+
+	spin_lock(&fld->lcf_lock);
+	list_for_each_entry_safe(target, tmp,
+				     &fld->lcf_targets, ft_chain) {
+		fld->lcf_count--;
+		list_del(&target->ft_chain);
+		if (target->ft_exp != NULL)
+			class_export_put(target->ft_exp);
+		OBD_FREE_PTR(target);
+	}
+	spin_unlock(&fld->lcf_lock);
+
+	if (fld->lcf_cache != NULL) {
+		if (!IS_ERR(fld->lcf_cache))
+			fld_cache_fini(fld->lcf_cache);
+		fld->lcf_cache = NULL;
+	}
+
+	EXIT;
+}
+EXPORT_SYMBOL(fld_client_fini);
+
+int fld_client_rpc(struct obd_export *exp,
+		   struct lu_seq_range *range, __u32 fld_op)
+{
+	struct ptlrpc_request *req;
+	struct lu_seq_range   *prange;
+	__u32		 *op;
+	int		    rc;
+	struct obd_import     *imp;
+	ENTRY;
+
+	LASSERT(exp != NULL);
+
+	imp = class_exp2cliimp(exp);
+	req = ptlrpc_request_alloc_pack(imp, &RQF_FLD_QUERY, LUSTRE_MDS_VERSION,
+					FLD_QUERY);
+	if (req == NULL)
+		RETURN(-ENOMEM);
+
+	op = req_capsule_client_get(&req->rq_pill, &RMF_FLD_OPC);
+	*op = fld_op;
+
+	prange = req_capsule_client_get(&req->rq_pill, &RMF_FLD_MDFLD);
+	*prange = *range;
+
+	ptlrpc_request_set_replen(req);
+	req->rq_request_portal = FLD_REQUEST_PORTAL;
+	ptlrpc_at_set_req_timeout(req);
+
+	if (fld_op == FLD_LOOKUP &&
+	    imp->imp_connect_flags_orig & OBD_CONNECT_MDS_MDS)
+		req->rq_allow_replay = 1;
+
+	if (fld_op != FLD_LOOKUP)
+		mdc_get_rpc_lock(exp->exp_obd->u.cli.cl_rpc_lock, NULL);
+	fld_enter_request(&exp->exp_obd->u.cli);
+	rc = ptlrpc_queue_wait(req);
+	fld_exit_request(&exp->exp_obd->u.cli);
+	if (fld_op != FLD_LOOKUP)
+		mdc_put_rpc_lock(exp->exp_obd->u.cli.cl_rpc_lock, NULL);
+	if (rc)
+		GOTO(out_req, rc);
+
+	prange = req_capsule_server_get(&req->rq_pill, &RMF_FLD_MDFLD);
+	if (prange == NULL)
+		GOTO(out_req, rc = -EFAULT);
+	*range = *prange;
+	EXIT;
+out_req:
+	ptlrpc_req_finished(req);
+	return rc;
+}
+
+int fld_client_lookup(struct lu_client_fld *fld, seqno_t seq, mdsno_t *mds,
+		      __u32 flags, const struct lu_env *env)
+{
+	struct lu_seq_range res = { 0 };
+	struct lu_fld_target *target;
+	int rc;
+	ENTRY;
+
+	fld->lcf_flags |= LUSTRE_FLD_RUN;
+
+	rc = fld_cache_lookup(fld->lcf_cache, seq, &res);
+	if (rc == 0) {
+		*mds = res.lsr_index;
+		RETURN(0);
+	}
+
+	/* Can not find it in the cache */
+	target = fld_client_get_target(fld, seq);
+	LASSERT(target != NULL);
+
+	CDEBUG(D_INFO, "%s: Lookup fld entry (seq: "LPX64") on "
+	       "target %s (idx "LPU64")\n", fld->lcf_name, seq,
+	       fld_target_name(target), target->ft_idx);
+
+	res.lsr_start = seq;
+	fld_range_set_type(&res, flags);
+	if (target->ft_srv != NULL) {
+		LASSERT(env != NULL);
+		rc = fld_server_lookup(env, target->ft_srv, seq, &res);
+	} else {
+		rc = fld_client_rpc(target->ft_exp, &res, FLD_LOOKUP);
+	}
+
+	if (rc == 0) {
+		*mds = res.lsr_index;
+
+		fld_cache_insert(fld->lcf_cache, &res);
+	}
+	RETURN(rc);
+}
+EXPORT_SYMBOL(fld_client_lookup);
+
+void fld_client_flush(struct lu_client_fld *fld)
+{
+	fld_cache_flush(fld->lcf_cache);
+}
+EXPORT_SYMBOL(fld_client_flush);