From: Ramachandra K <ramachandra.kuchimanchi@qlogic.com>
To: rdreier@cisco.com, general@lists.openfabrics.org, netdev@vger.kernel.org
Cc: poornima.kamath@qlogic.com, amar.mudrankit@qlogic.com
Subject: [ofa-general] [PATCH 09/13] QLogic VNIC: IB Multicast for Ethernet broadcast/multicast
Date: Wed, 30 Apr 2008 22:50:25 +0530 [thread overview]
Message-ID: <20080430172025.31725.97795.stgit@localhost.localdomain> (raw)
In-Reply-To: <20080430171028.31725.86190.stgit@localhost.localdomain>
From: Usha Srinivasan <usha.srinivasan@qlogic.com>
Implementation of ethernet broadcasting and multicasting for QLogic
VNIC interface by making use of underlying IB multicasting.
Signed-off-by: Ramachandra K <ramachandra.kuchimanchi@qlogic.com>
Signed-off-by: Poornima Kamath <poornima.kamath@qlogic.com>
Signed-off-by: Amar Mudrankit <amar.mudrankit@qlogic.com>
---
drivers/infiniband/ulp/qlgc_vnic/vnic_multicast.c | 332 +++++++++++++++++++++
drivers/infiniband/ulp/qlgc_vnic/vnic_multicast.h | 76 +++++
2 files changed, 408 insertions(+), 0 deletions(-)
create mode 100644 drivers/infiniband/ulp/qlgc_vnic/vnic_multicast.c
create mode 100644 drivers/infiniband/ulp/qlgc_vnic/vnic_multicast.h
diff --git a/drivers/infiniband/ulp/qlgc_vnic/vnic_multicast.c b/drivers/infiniband/ulp/qlgc_vnic/vnic_multicast.c
new file mode 100644
index 0000000..044d447
--- /dev/null
+++ b/drivers/infiniband/ulp/qlgc_vnic/vnic_multicast.c
@@ -0,0 +1,332 @@
+/*
+ * Copyright (c) 2008 QLogic, Inc. All rights reserved.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses. You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ * 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.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include <linux/net.h>
+#include <linux/netdevice.h>
+#include <linux/jiffies.h>
+#include <rdma/ib_sa.h>
+#include "vnic_viport.h"
+#include "vnic_netpath.h"
+#include "vnic_main.h"
+#include "vnic_config.h"
+#include "vnic_control.h"
+#include "vnic_util.h"
+#include "vnic_ib.h"
+
+#define control_ifcfg_name(p)\
+ ((p)->parent->parent->parent->config->name)
+
+#define SET_MCAST_STATE_INVALID \
+do { \
+ viport->mc_info.state = MCAST_STATE_INVALID; \
+ viport->mc_info.mc = NULL; \
+ memset(&viport->mc_info.mgid, 0, sizeof(union ib_gid)); \
+} while (0);
+
+int vnic_mc_init(struct viport *viport)
+{
+ MCAST_FUNCTION("vnic_mc_init %p\n", viport);
+ SET_MCAST_STATE_INVALID;
+ viport->mc_info.retries = 0;
+ spin_lock_init(&viport->mc_info.lock);
+
+ return 0;
+}
+
+void vnic_mc_uninit(struct viport *viport)
+{
+ unsigned long flags;
+ MCAST_FUNCTION("vnic_mc_uninit %p\n", viport);
+
+ spin_lock_irqsave(&viport->mc_info.lock, flags);
+ if ((viport->mc_info.state != MCAST_STATE_INVALID) &&
+ (viport->mc_info.state != MCAST_STATE_RETRIED)) {
+ MCAST_ERROR("%s mcast state is not INVALID or RETRIED %d\n",
+ control_ifcfg_name(&viport->control),
+ viport->mc_info.state);
+ }
+ spin_unlock_irqrestore(&viport->mc_info.lock, flags);
+ MCAST_FUNCTION("vnic_mc_uninit done\n");
+}
+
+
+/* This function is called when NEED_MCAST_COMPLETION is set.
+ * It finishes off the join multicast work.
+ */
+int vnic_mc_join_handle_completion(struct viport *viport)
+{
+ unsigned long flags;
+ unsigned int ret = 0;
+
+ MCAST_FUNCTION("in vnic_mc_join_handle_completion\n");
+ spin_lock_irqsave(&viport->mc_info.lock, flags);
+ if (viport->mc_info.state != MCAST_STATE_JOINING) {
+ MCAST_ERROR("%s unexpected mcast state in handle_completion: "
+ " %d\n", control_ifcfg_name(&viport->control),
+ viport->mc_info.state);
+ spin_unlock_irqrestore(&viport->mc_info.lock, flags);
+ return -1;
+ }
+ viport->mc_info.state = MCAST_STATE_ATTACHING;
+ spin_unlock_irqrestore(&viport->mc_info.lock, flags);
+ MCAST_INFO("%s calling ib_attach_mcast %lx mgid:"
+ VNIC_GID_FMT " mlid:%x\n",
+ control_ifcfg_name(&viport->control), jiffies,
+ VNIC_GID_RAW_ARG(viport->mc_info.mgid.raw),
+ viport->mc_info.mlid);
+ ret = ib_attach_mcast(viport->mc_data.ib_conn.qp, &viport->mc_info.mgid,
+ viport->mc_info.mlid);
+ if (ret) {
+ MCAST_ERROR("%s attach mcast qp failed %d\n",
+ control_ifcfg_name(&viport->control), ret);
+ return -1;
+ }
+ MCAST_INFO("%s attached\n",
+ control_ifcfg_name(&viport->control));
+ spin_lock_irqsave(&viport->mc_info.lock, flags);
+ viport->mc_info.state = MCAST_STATE_JOINED_ATTACHED;
+ MCAST_INFO("%s qp attached to mcast group\n",
+ control_ifcfg_name(&viport->control));
+ spin_unlock_irqrestore(&viport->mc_info.lock, flags);
+ return 0;
+}
+
+/* NOTE: ib_sa.h says "returning a non-zero value from this callback will
+ * result in destroying the multicast tracking structure.
+ */
+static int vnic_mc_join_complete(int status,
+ struct ib_sa_multicast *multicast)
+{
+ struct viport *viport = (struct viport *)multicast->context;
+ unsigned long flags;
+
+ MCAST_FUNCTION("in vnic_mc_join_complete status:%x\n", status);
+ if (status) {
+ spin_lock_irqsave(&viport->mc_info.lock, flags);
+ if (status == -ENETRESET) {
+ SET_MCAST_STATE_INVALID;
+ viport->mc_info.retries = 0;
+ spin_unlock_irqrestore(&viport->mc_info.lock, flags);
+ MCAST_ERROR("%s got ENETRESET what's the right thing "
+ "to do?\n",
+ control_ifcfg_name(&viport->control));
+ return status;
+ }
+ /* perhaps the mcgroup hasn't yet been created - retry */
+ viport->mc_info.retries++;
+ viport->mc_info.mc = NULL;
+ if (viport->mc_info.retries > MAX_MCAST_JOIN_RETRIES) {
+ viport->mc_info.state = MCAST_STATE_RETRIED;
+ spin_unlock_irqrestore(&viport->mc_info.lock, flags);
+ MCAST_ERROR("%s join failed 0x%x - max retries:%d "
+ "exceeded\n",
+ control_ifcfg_name(&viport->control),
+ status, viport->mc_info.retries);
+ } else {
+ viport->mc_info.state = MCAST_STATE_INVALID;
+ spin_unlock_irqrestore(&viport->mc_info.lock, flags);
+ spin_lock_irqsave(&viport->lock, flags);
+ viport->updates |= NEED_MCAST_JOIN;
+ spin_unlock_irqrestore(&viport->lock, flags);
+ viport_kick(viport);
+ MCAST_ERROR("%s join failed 0x%x - retrying; "
+ "retries:%d\n",
+ control_ifcfg_name(&viport->control),
+ status, viport->mc_info.retries);
+ }
+ return status;
+ }
+
+ /* finish join work from main state loop for viport - in case
+ * the work itself cannot be done in a callback environment */
+ spin_lock_irqsave(&viport->lock, flags);
+ viport->mc_info.mlid = be16_to_cpu(multicast->rec.mlid);
+ viport->updates |= NEED_MCAST_COMPLETION;
+ spin_unlock_irqrestore(&viport->lock, flags);
+ viport_kick(viport);
+ MCAST_INFO("%s set NEED_MCAST_COMPLETION %x %x\n",
+ control_ifcfg_name(&viport->control),
+ multicast->rec.mlid, viport->mc_info.mlid);
+ return 0;
+}
+
+void vnic_mc_join_setup(struct viport *viport, union ib_gid *mgid)
+{
+ unsigned long flags;
+
+ MCAST_FUNCTION("in vnic_mc_join_setup\n");
+ spin_lock_irqsave(&viport->mc_info.lock, flags);
+ if (viport->mc_info.state != MCAST_STATE_INVALID) {
+ if (viport->mc_info.state == MCAST_STATE_DETACHING) {
+ MCAST_ERROR("%s detach in progress\n",
+ control_ifcfg_name(&viport->control));
+ } else if (viport->mc_info.state == MCAST_STATE_RETRIED) {
+ MCAST_ERROR("%s max join retries exceeded\n",
+ control_ifcfg_name(&viport->control));
+ } else {
+ /* join/attach in progress or done */
+ /* verify that the current mgid is same as prev mgid */
+ if (memcmp(mgid, &viport->mc_info.mgid, sizeof(union ib_gid)) != 0) {
+ /* Separate MGID for each IOC */
+ MCAST_ERROR("%s Multicast Group MGIDs not "
+ "unique; mgids: " VNIC_GID_FMT
+ " " VNIC_GID_FMT "\n",
+ control_ifcfg_name(&viport->control),
+ VNIC_GID_RAW_ARG(mgid->raw),
+ VNIC_GID_RAW_ARG(viport->mc_info.mgid.raw));
+ } else
+ MCAST_INFO("%s join already issued: %d\n",
+ control_ifcfg_name(&viport->control),
+ viport->mc_info.state);
+
+ }
+ spin_unlock_irqrestore(&viport->mc_info.lock, flags);
+ return;
+ }
+ viport->mc_info.mgid = *mgid;
+ spin_unlock_irqrestore(&viport->mc_info.lock, flags);
+ spin_lock_irqsave(&viport->lock, flags);
+ viport->updates |= NEED_MCAST_JOIN;
+ spin_unlock_irqrestore(&viport->lock, flags);
+ viport_kick(viport);
+ MCAST_INFO("%s set NEED_MCAST_JOIN \n",
+ control_ifcfg_name(&viport->control));
+}
+
+int vnic_mc_join(struct viport *viport)
+{
+ struct ib_sa_mcmember_rec rec;
+ ib_sa_comp_mask comp_mask;
+ unsigned long flags;
+
+ MCAST_FUNCTION("in vnic_mc_join\n");
+ if (!viport->mc_data.ib_conn.qp) {
+ MCAST_ERROR("%s qp is NULL\n",
+ control_ifcfg_name(&viport->control));
+ return -1;
+ }
+ spin_lock_irqsave(&viport->mc_info.lock, flags);
+ if (viport->mc_info.state != MCAST_STATE_INVALID) {
+ MCAST_INFO("%s join already issued: %d\n",
+ control_ifcfg_name(&viport->control),
+ viport->mc_info.state);
+ spin_unlock_irqrestore(&viport->mc_info.lock, flags);
+ return 0;
+ }
+ viport->mc_info.state = MCAST_STATE_JOINING;
+ spin_unlock_irqrestore(&viport->mc_info.lock, flags);
+
+ memset(&rec, 0, sizeof(rec));
+ rec.join_state = 2; /* bit 1 is Nonmember */
+ rec.mgid = viport->mc_info.mgid;
+ rec.port_gid = viport->config->path_info.path.sgid;
+
+ comp_mask = IB_SA_MCMEMBER_REC_MGID |
+ IB_SA_MCMEMBER_REC_PORT_GID |
+ IB_SA_MCMEMBER_REC_JOIN_STATE;
+
+ MCAST_INFO("%s calling ib_sa_join_multicast %lx mgid:"
+ VNIC_GID_FMT " port_gid: " VNIC_GID_FMT "\n",
+ control_ifcfg_name(&viport->control), jiffies,
+ VNIC_GID_RAW_ARG(rec.mgid.raw),
+ VNIC_GID_RAW_ARG(rec.port_gid.raw));
+
+ viport->mc_info.mc = ib_sa_join_multicast(&vnic_sa_client,
+ viport->config->ibdev, viport->config->port,
+ &rec, comp_mask, GFP_KERNEL,
+ vnic_mc_join_complete, viport);
+
+ if (IS_ERR(viport->mc_info.mc)) {
+ MCAST_ERROR("%s ib_sa_join_multicast failed " VNIC_GID_FMT
+ ".\n",
+ control_ifcfg_name(&viport->control),
+ VNIC_GID_RAW_ARG(rec.mgid.raw));
+ spin_lock_irqsave(&viport->mc_info.lock, flags);
+ viport->mc_info.state = MCAST_STATE_INVALID;
+ spin_unlock_irqrestore(&viport->mc_info.lock, flags);
+ return -1;
+ }
+ MCAST_INFO("%s join issued ib_sa_join_multicast mgid:"
+ VNIC_GID_FMT " port_gid: " VNIC_GID_FMT "\n",
+ control_ifcfg_name(&viport->control),
+ VNIC_GID_RAW_ARG(rec.mgid.raw),
+ VNIC_GID_RAW_ARG(rec.port_gid.raw));
+
+ return 0;
+}
+
+void vnic_mc_leave(struct viport *viport)
+{
+ unsigned long flags;
+ unsigned int ret;
+ struct ib_sa_multicast *mc;
+
+ MCAST_FUNCTION("vnic_mc_leave \n");
+
+ spin_lock_irqsave(&viport->mc_info.lock, flags);
+ if ((viport->mc_info.state == MCAST_STATE_INVALID) ||
+ (viport->mc_info.state == MCAST_STATE_RETRIED)) {
+ spin_unlock_irqrestore(&viport->mc_info.lock, flags);
+ return;
+ }
+
+ if (viport->mc_info.state == MCAST_STATE_JOINED_ATTACHED) {
+
+ viport->mc_info.state = MCAST_STATE_DETACHING;
+ spin_unlock_irqrestore(&viport->mc_info.lock, flags);
+ ret = ib_detach_mcast(viport->mc_data.ib_conn.qp,
+ &viport->mc_info.mgid,
+ viport->mc_info.mlid);
+ if (ret) {
+ MCAST_ERROR("%s detach failed %d\n",
+ control_ifcfg_name(&viport->control), ret);
+ return;
+ }
+ MCAST_INFO("%s detached succesfully\n",
+ control_ifcfg_name(&viport->control));
+ spin_lock_irqsave(&viport->mc_info.lock, flags);
+ }
+ mc = viport->mc_info.mc;
+ SET_MCAST_STATE_INVALID;
+ viport->mc_info.retries = 0;
+ spin_unlock_irqrestore(&viport->mc_info.lock, flags);
+
+ if (mc) {
+ MCAST_INFO("%s calling ib_sa_free_multicast\n",
+ control_ifcfg_name(&viport->control));
+ ib_sa_free_multicast(mc);
+ }
+ MCAST_FUNCTION("vnic_mc_leave done\n");
+ return;
+}
+
+
diff --git a/drivers/infiniband/ulp/qlgc_vnic/vnic_multicast.h b/drivers/infiniband/ulp/qlgc_vnic/vnic_multicast.h
new file mode 100644
index 0000000..0e5499d
--- /dev/null
+++ b/drivers/infiniband/ulp/qlgc_vnic/vnic_multicast.h
@@ -0,0 +1,76 @@
+/*
+ * Copyright (c) 2008 QLogic, Inc. All rights reserved.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses. You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ * 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.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#ifndef __VNIC_MULTICAST_H__
+#define __VNIC_MULTTCAST_H__
+
+enum {
+ MCAST_STATE_INVALID = 0x00, /* join not attempted or failed */
+ MCAST_STATE_JOINING = 0x01, /* join mcgroup in progress */
+ MCAST_STATE_ATTACHING = 0x02, /* join completed with success,
+ * attach qp to mcgroup in progress
+ */
+ MCAST_STATE_JOINED_ATTACHED = 0x03, /* join completed with success */
+ MCAST_STATE_DETACHING = 0x04, /* detach qp in progress */
+ MCAST_STATE_RETRIED = 0x05, /* retried join and failed */
+};
+
+#define MAX_MCAST_JOIN_RETRIES 5 /* used to retry join */
+
+struct mc_info {
+ u8 state;
+ spinlock_t lock;
+ union ib_gid mgid;
+ u16 mlid;
+ struct ib_sa_multicast *mc;
+ u8 retries;
+};
+
+
+int vnic_mc_init(struct viport *viport);
+void vnic_mc_uninit(struct viport *viport);
+
+/* This function is called when a viport gets a multicast mgid from EVIC
+ and must join the multicast group. It sets up NEED_MCAST_JOIN flag, which
+ results in vnic_mc_join being called later. */
+void vnic_mc_join_setup(struct viport *viport, union ib_gid *mgid);
+
+/* This function is called when NEED_MCAST_JOIN flag is set. */
+int vnic_mc_join(struct viport *viport);
+
+/* This function is called when NEED_MCAST_COMPLETION is set.
+ It finishes off the join multicast work. */
+int vnic_mc_join_handle_completion(struct viport *viport);
+
+void vnic_mc_leave(struct viport *viport);
+
+#endif /* __VNIC_MULTICAST_H__ */
next prev parent reply other threads:[~2008-04-30 17:20 UTC|newest]
Thread overview: 32+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-04-30 17:15 [ofa-general] [PATCH 00/13] QLogic Virtual NIC (VNIC) Driver Ramachandra K
2008-04-30 17:16 ` [ofa-general] [PATCH 01/13] QLogic VNIC: Driver - netdev implementation Ramachandra K
2008-05-02 18:15 ` Roland Dreier
2008-05-05 15:36 ` [ofa-general] " Ramachandra K
2008-05-05 20:42 ` Roland Dreier
2008-04-30 17:16 ` [ofa-general] [PATCH 02/13] QLogic VNIC: Netpath - abstraction of connection to EVIC/VEx Ramachandra K
2008-04-30 17:17 ` [ofa-general] [PATCH 03/13] QLogic VNIC: Implementation of communication protocol with EVIC/VEx Ramachandra K
2008-04-30 17:17 ` [ofa-general] [PATCH 04/13] QLogic VNIC: Implementation of Control path of communication protocol Ramachandra K
2008-04-30 17:18 ` [ofa-general] [PATCH 05/13] QLogic VNIC: Implementation of Data " Ramachandra K
2008-04-30 17:18 ` [ofa-general] [PATCH 06/13] QLogic VNIC: IB core stack interaction Ramachandra K
2008-05-13 20:40 ` [ofa-general] " Roland Dreier
2008-04-30 17:19 ` [ofa-general] [PATCH 07/13] QLogic VNIC: Handling configurable parameters of the driver Ramachandra K
2008-05-13 20:41 ` Roland Dreier
2008-04-30 17:19 ` [ofa-general] [PATCH 08/13] QLogic VNIC: sysfs interface implementation for " Ramachandra K
2008-05-01 14:56 ` Stephen Hemminger
2008-05-01 16:02 ` [ofa-general] " Kuchimanchi, Ramachandra (Contractor - )
2008-05-01 16:43 ` [ofa-general] [RESEND] " Ramachandra K
2008-05-01 18:22 ` [ofa-general] " Stephen Hemminger
2008-04-30 17:20 ` Ramachandra K [this message]
2008-05-15 22:38 ` [ofa-general] [PATCH 09/13] QLogic VNIC: IB Multicast for Ethernet broadcast/multicast Roland Dreier
2008-04-30 17:20 ` [ofa-general] [PATCH 10/13] QLogic VNIC: Driver Statistics collection Ramachandra K
2008-05-15 22:33 ` Roland Dreier
2008-05-20 16:52 ` [ofa-general] " Ramachandra K
2008-04-30 17:21 ` [PATCH 11/13] QLogic VNIC: Driver utility file - implements various utility macros Ramachandra K
2008-05-01 14:58 ` [ofa-general] " Stephen Hemminger
2008-05-01 16:18 ` [ofa-general] " Kuchimanchi, Ramachandra (Contractor - )
2008-05-01 17:01 ` Ramachandra K
2008-05-01 18:26 ` Stephen Hemminger
2008-04-30 17:21 ` [ofa-general] [PATCH 12/13] QLogic VNIC: Driver Kconfig and Makefile Ramachandra K
2008-05-15 22:31 ` Roland Dreier
2008-04-30 17:22 ` [ofa-general] [PATCH 13/13] QLogic VNIC: Modifications to IB " Ramachandra K
2008-04-30 22:25 ` [ofa-general] Re: [PATCH 00/13] QLogic Virtual NIC (VNIC) Driver Roland Dreier
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