[PATCH 21/28] IB/srpt: One target per port

Bart Van Assche
2018-01-03T21:39:31Z

In multipathing setups where a target system is equipped with
dual-port HCAs it is useful to have one connection per target port
instead of one connection per target HCA. Hence move the connection
list (rch_list) from struct srpt_device into struct srpt_port.

Signed-off-by: Bart Van Assche <bart.vanassche-Sjgp3cTcYWE@public.gmane.org>
---
drivers/infiniband/ulp/srpt/ib_srpt.c | 102 +++++++++++++++++-----------------
drivers/infiniband/ulp/srpt/ib_srpt.h | 20 +++----
2 files changed, 62 insertions(+), 60 deletions(-)

diff --git a/drivers/infiniband/ulp/srpt/ib_srpt.c b/drivers/infiniband/ulp/srpt/ib_srpt.c
index eeeb47739e9a..d8c695135024 100644
--- a/drivers/infiniband/ulp/srpt/ib_srpt.c
+++ b/drivers/infiniband/ulp/srpt/ib_srpt.c
@@ -1781,13 +1781,13 @@ static int srpt_disconnect_ch(struct srpt_rdma_ch *ch)
return ret;
}

-static bool srpt_ch_closed(struct srpt_device *sdev, struct srpt_rdma_ch *ch)
+static bool srpt_ch_closed(struct srpt_port *sport, struct srpt_rdma_ch *ch)
{
struct srpt_rdma_ch *ch2;
bool res = true;

rcu_read_lock();
- list_for_each_entry(ch2, &sdev->rch_list, list) {
+ list_for_each_entry(ch2, &sport->rch_list, list) {
if (ch2 == ch) {
res = false;
goto done;
@@ -1806,33 +1806,32 @@ static bool srpt_ch_closed(struct srpt_device *sdev, struct srpt_rdma_ch *ch)
static bool srpt_disconnect_ch_sync(struct srpt_rdma_ch *ch)
__must_hold(&sdev->mutex)
{
- struct srpt_device *sdev = ch->sport->sdev;
+ struct srpt_port *sport = ch->sport;
int ret;

- lockdep_assert_held(&sdev->mutex);
+ lockdep_assert_held(&sport->mutex);

pr_debug("ch %s-%d state %d\n", ch->sess_name, ch->qp->qp_num,
ch->state);

ret = srpt_disconnect_ch(ch);
- mutex_unlock(&sdev->mutex);
+ mutex_unlock(&sport->mutex);

- while (wait_event_timeout(sdev->ch_releaseQ, srpt_ch_closed(sdev, ch),
+ while (wait_event_timeout(sport->ch_releaseQ, srpt_ch_closed(sport, ch),
5 * HZ) == 0)
pr_info("%s(%s-%d state %d): still waiting ...\n", __func__,
ch->sess_name, ch->qp->qp_num, ch->state);

- mutex_lock(&sdev->mutex);
+ mutex_lock(&sport->mutex);
return ret == 0;
}

static void srpt_set_enabled(struct srpt_port *sport, bool enabled)
- __must_hold(&sdev->mutex)
+ __must_hold(&sport->mutex)
{
- struct srpt_device *sdev = sport->sdev;
struct srpt_rdma_ch *ch;

- lockdep_assert_held(&sdev->mutex);
+ lockdep_assert_held(&sport->mutex);

if (sport->enabled == enabled)
return;
@@ -1841,10 +1840,10 @@ static void srpt_set_enabled(struct srpt_port *sport, bool enabled)
return;

again:
- list_for_each_entry(ch, &sdev->rch_list, list) {
+ list_for_each_entry(ch, &sport->rch_list, list) {
if (ch->sport == sport) {
pr_info("%s: closing channel %s-%d\n",
- sdev->device->name, ch->sess_name,
+ sport->sdev->device->name, ch->sess_name,
ch->qp->qp_num);
if (srpt_disconnect_ch_sync(ch))
goto again;
@@ -1864,6 +1863,7 @@ static void srpt_release_channel_work(struct work_struct *w)
{
struct srpt_rdma_ch *ch;
struct srpt_device *sdev;
+ struct srpt_port *sport;
struct se_session *se_sess;

ch = container_of(w, struct srpt_rdma_ch, release_work);
@@ -1894,11 +1894,12 @@ static void srpt_release_channel_work(struct work_struct *w)
sdev, ch->rq_size,
srp_max_req_size, DMA_FROM_DEVICE);

- mutex_lock(&sdev->mutex);
+ sport = ch->sport;
+ mutex_lock(&sport->mutex);
list_del_init(&ch->list);
- mutex_unlock(&sdev->mutex);
+ mutex_unlock(&sport->mutex);

- wake_up(&sdev->ch_releaseQ);
+ wake_up(&sport->ch_releaseQ);

kref_put(&ch->kref, srpt_free_ch);
}
@@ -1920,6 +1921,7 @@ static int srpt_cm_req_recv(struct ib_cm_id *cm_id,
struct srp_login_rej *rej;
struct ib_cm_rep_param *rep_param;
struct srpt_rdma_ch *ch, *tmp_ch;
+ char *ini_guid, i_port_id[36];
u32 it_iu_len;
int i, ret = 0;

@@ -1968,9 +1970,9 @@ static int srpt_cm_req_recv(struct ib_cm_id *cm_id,
if ((req->req_flags & SRP_MTCH_ACTION) == SRP_MULTICHAN_SINGLE) {
rsp->rsp_flags = SRP_LOGIN_RSP_MULTICHAN_NO_CHAN;

- mutex_lock(&sdev->mutex);
+ mutex_lock(&sport->mutex);

- list_for_each_entry_safe(ch, tmp_ch, &sdev->rch_list, list) {
+ list_for_each_entry_safe(ch, tmp_ch, &sport->rch_list, list) {
if (!memcmp(ch->i_port_id, req->initiator_port_id, 16)
&& !memcmp(ch->t_port_id, req->target_port_id, 16)
&& param->port == ch->sport->port
@@ -1985,7 +1987,7 @@ static int srpt_cm_req_recv(struct ib_cm_id *cm_id,
}
}

- mutex_unlock(&sdev->mutex);
+ mutex_unlock(&sport->mutex);

} else
rsp->rsp_flags = SRP_LOGIN_RSP_MULTICHAN_MAINTAINED;
@@ -2074,9 +2076,10 @@ static int srpt_cm_req_recv(struct ib_cm_id *cm_id,
goto destroy_ib;
}

- srpt_format_guid(ch->ini_guid, sizeof(ch->ini_guid),
+ srpt_format_guid(ch->sess_name, sizeof(ch->sess_name),
&param->primary_path->dgid.global.interface_id);
- snprintf(ch->sess_name, sizeof(ch->sess_name), "0x%016llx%016llx",
+ ini_guid = ch->sess_name;
+ snprintf(i_port_id, sizeof(i_port_id), "0x%016llx%016llx",
be64_to_cpu(*(__be64 *)ch->i_port_id),
be64_to_cpu(*(__be64 *)(ch->i_port_id + 8)));

@@ -2084,17 +2087,17 @@ static int srpt_cm_req_recv(struct ib_cm_id *cm_id,

if (sport->port_guid_tpg.se_tpg_wwn)
ch->sess = target_alloc_session(&sport->port_guid_tpg, 0, 0,
- TARGET_PROT_NORMAL,
- ch->ini_guid, ch, NULL);
+ TARGET_PROT_NORMAL, ini_guid,
+ ch, NULL);
if (sport->port_gid_tpg.se_tpg_wwn && IS_ERR_OR_NULL(ch->sess))
ch->sess = target_alloc_session(&sport->port_gid_tpg, 0, 0,
- TARGET_PROT_NORMAL, ch->sess_name, ch,
+ TARGET_PROT_NORMAL, i_port_id, ch,
NULL);
/* Retry without leading "0x" */
if (sport->port_gid_tpg.se_tpg_wwn && IS_ERR_OR_NULL(ch->sess))
ch->sess = target_alloc_session(&sport->port_gid_tpg, 0, 0,
TARGET_PROT_NORMAL,
- ch->sess_name + 2, ch, NULL);
+ i_port_id + 2, ch, NULL);
if (IS_ERR_OR_NULL(ch->sess)) {
pr_info("Rejected login because no ACL has been configured yet for initiator %s.\n",
ch->sess_name);
@@ -2137,9 +2140,9 @@ static int srpt_cm_req_recv(struct ib_cm_id *cm_id,
goto release_channel;
}

- mutex_lock(&sdev->mutex);
- list_add_tail_rcu(&ch->list, &sdev->rch_list);
- mutex_unlock(&sdev->mutex);
+ mutex_lock(&sport->mutex);
+ list_add_tail_rcu(&ch->list, &sport->rch_list);
+ mutex_unlock(&sport->mutex);

goto out;

@@ -2487,23 +2490,20 @@ static void srpt_refresh_port_work(struct work_struct *work)
}

/*
- * srpt_release_sdev() - Free the channel resources associated with a target.
+ * srpt_release_sport() - Free the channel resources associated with a target.
*/
-static int srpt_release_sdev(struct srpt_device *sdev)
+static int srpt_release_sport(struct srpt_port *sport)
{
- int i, res;
+ int res;

WARN_ON_ONCE(irqs_disabled());

- BUG_ON(!sdev);
-
- mutex_lock(&sdev->mutex);
- for (i = 0; i < ARRAY_SIZE(sdev->port); i++)
- srpt_set_enabled(&sdev->port[i], false);
- mutex_unlock(&sdev->mutex);
+ mutex_lock(&sport->mutex);
+ srpt_set_enabled(sport, false);
+ mutex_unlock(&sport->mutex);

- res = wait_event_interruptible(sdev->ch_releaseQ,
- list_empty_careful(&sdev->rch_list));
+ res = wait_event_interruptible(sport->ch_releaseQ,
+ list_empty_careful(&sport->rch_list));
if (res)
pr_err("%s: interrupted.\n", __func__);

@@ -2630,9 +2630,7 @@ static void srpt_add_one(struct ib_device *device)
goto err;

sdev->device = device;
- INIT_LIST_HEAD(&sdev->rch_list);
- init_waitqueue_head(&sdev->ch_releaseQ);
- mutex_init(&sdev->mutex);
+ mutex_init(&sdev->sdev_mutex);

sdev->pd = ib_alloc_pd(device, 0);
if (IS_ERR(sdev->pd))
@@ -2673,6 +2671,9 @@ static void srpt_add_one(struct ib_device *device)

for (i = 1; i <= sdev->device->phys_port_cnt; i++) {
sport = &sdev->port[i - 1];
+ INIT_LIST_HEAD(&sport->rch_list);
+ init_waitqueue_head(&sport->ch_releaseQ);
+ mutex_init(&sport->mutex);
sport->sdev = sdev;
sport->port = i;
sport->port_attrib.srp_max_rdma_size = DEFAULT_MAX_RDMA_SIZE;
@@ -2743,7 +2744,9 @@ static void srpt_remove_one(struct ib_device *device, void *client_data)
spin_lock(&srpt_dev_lock);
list_del(&sdev->list);
spin_unlock(&srpt_dev_lock);
- srpt_release_sdev(sdev);
+
+ for (i = 0; i < sdev->device->phys_port_cnt; i++)
+ srpt_release_sport(&sdev->port[i]);

srpt_free_srq(sdev);

@@ -2828,11 +2831,11 @@ static void srpt_release_cmd(struct se_cmd *se_cmd)
static void srpt_close_session(struct se_session *se_sess)
{
struct srpt_rdma_ch *ch = se_sess->fabric_sess_ptr;
- struct srpt_device *sdev = ch->sport->sdev;
+ struct srpt_port *sport = ch->sport;

- mutex_lock(&sdev->mutex);
+ mutex_lock(&sport->mutex);
srpt_disconnect_ch_sync(ch);
- mutex_unlock(&sdev->mutex);
+ mutex_unlock(&sport->mutex);
}

/*
@@ -3056,7 +3059,7 @@ static ssize_t srpt_tpg_attrib_use_srq_store(struct config_item *item,
if (val != !!val)
return -EINVAL;

- ret = mutex_lock_interruptible(&sdev->mutex);
+ ret = mutex_lock_interruptible(&sdev->sdev_mutex);
if (ret < 0)
return ret;
enabled = sport->enabled;
@@ -3065,7 +3068,7 @@ static ssize_t srpt_tpg_attrib_use_srq_store(struct config_item *item,
sport->port_attrib.use_srq = val;
srpt_use_srq(sdev, sport->port_attrib.use_srq);
srpt_set_enabled(sport, enabled);
- mutex_unlock(&sdev->mutex);
+ mutex_unlock(&sdev->sdev_mutex);

return count;
}
@@ -3096,7 +3099,6 @@ static ssize_t srpt_tpg_enable_store(struct config_item *item,
{
struct se_portal_group *se_tpg = to_tpg(item);
struct srpt_port *sport = srpt_tpg_to_sport(se_tpg);
- struct srpt_device *sdev = sport->sdev;
unsigned long tmp;
int ret;

@@ -3111,9 +3113,9 @@ static ssize_t srpt_tpg_enable_store(struct config_item *item,
return -EINVAL;
}

- mutex_lock(&sdev->mutex);
+ mutex_lock(&sport->mutex);
srpt_set_enabled(sport, tmp);
- mutex_unlock(&sdev->mutex);
+ mutex_unlock(&sport->mutex);

return count;
}
diff --git a/drivers/infiniband/ulp/srpt/ib_srpt.h b/drivers/infiniband/ulp/srpt/ib_srpt.h
index dd44e51fa167..82b93e2a2efb 100644
--- a/drivers/infiniband/ulp/srpt/ib_srpt.h
+++ b/drivers/infiniband/ulp/srpt/ib_srpt.h
@@ -262,14 +262,13 @@ enum rdma_ch_state {
* @state: channel state. See also enum rdma_ch_state.
* @ioctx_ring: Send ring.
* @ioctx_recv_ring: Receive I/O context ring.
- * @list: Node for insertion in the srpt_device.rch_list list.
+ * @list: Node in srpt_port.rch_list.
* @cmd_wait_list: List of SCSI commands that arrived before the RTU event. This
* list contains struct srpt_ioctx elements and is protected
* against concurrent modification by the cm_id spinlock.
* @pkey: P_Key of the IB partition for this SRP channel.
* @sess: Session information associated with this SRP channel.
* @sess_name: Session name.
- * @ini_guid: Initiator port GUID.
* @release_work: Allows scheduling of srpt_release_channel().
*/
struct srpt_rdma_ch {
@@ -297,8 +296,7 @@ struct srpt_rdma_ch {
struct list_head cmd_wait_list;
uint16_t pkey;
struct se_session *sess;
- u8 sess_name[36];
- u8 ini_guid[24];
+ u8 sess_name[24];
struct work_struct release_work;
};

@@ -334,6 +332,9 @@ struct srpt_port_attrib {
* @port_gid_tpg: TPG associated with target port GID.
* @port_gid_wwn: WWN associated with target port GID.
* @port_attrib: Port attributes that can be accessed through configfs.
+ * @ch_releaseQ: Enables waiting for removal from rch_list.
+ * @mutex: Protects rch_list.
+ * @rch_list: Channel list. See also srpt_rdma_ch.list.
*/
struct srpt_port {
struct srpt_device *sdev;
@@ -351,6 +352,9 @@ struct srpt_port {
struct se_portal_group port_gid_tpg;
struct se_wwn port_gid_wwn;
struct srpt_port_attrib port_attrib;
+ wait_queue_head_t ch_releaseQ;
+ struct mutex mutex;
+ struct list_head rch_list;
};

/**
@@ -361,11 +365,9 @@ struct srpt_port {
* @srq: Per-HCA SRQ (shared receive queue).
* @cm_id: Connection identifier.
* @srq_size: SRQ size.
+ * @sdev_mutex: Serializes use_srq changes.
* @use_srq: Whether or not to use SRQ.
* @ioctx_ring: Per-HCA SRQ.
- * @rch_list: Per-device channel list -- see also srpt_rdma_ch.list.
- * @ch_releaseQ: Enables waiting for removal from rch_list.
- * @mutex: Protects rch_list.
* @port: Information about the ports owned by this HCA.
* @event_handler: Per-HCA asynchronous IB event handler.
* @list: Node in srpt_dev_list.
@@ -377,11 +379,9 @@ struct srpt_device {
struct ib_srq *srq;
struct ib_cm_id *cm_id;
int srq_size;
+ struct mutex sdev_mutex;
bool use_srq;
struct srpt_recv_ioctx **ioctx_ring;
- struct list_head rch_list;
- wait_queue_head_t ch_releaseQ;
- struct mutex mutex;
struct srpt_port port[2];
struct ib_event_handler event_handler;
struct list_head list;