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IB/srpt: Rework multi-channel support
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Store initiator and target port ID's once per nexus instead of in each
channel data structure. This change simplifies the duplicate connection
check in srpt_cm_req_recv().

Signed-off-by: Bart Van Assche <[email protected]>
Signed-off-by: Doug Ledford <[email protected]>
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@KAGA-KOKO @dledford
KAGA-KOKO authored and dledford committed Jan 18, 2018
1 parent 2dc98f0 commit a112531
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Showing 2 changed files with 160 additions and 60 deletions.
186 changes: 135 additions & 51 deletions drivers/infiniband/ulp/srpt/ib_srpt.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1849,16 +1849,20 @@ static int srpt_disconnect_ch(struct srpt_rdma_ch *ch)

static bool srpt_ch_closed(struct srpt_port *sport, struct srpt_rdma_ch *ch)
{
struct srpt_nexus *nexus;
struct srpt_rdma_ch *ch2;
bool res = true;

rcu_read_lock();
list_for_each_entry(ch2, &sport->rch_list, list) {
if (ch2 == ch) {
res = false;
break;
list_for_each_entry(nexus, &sport->nexus_list, entry) {
list_for_each_entry(ch2, &nexus->ch_list, list) {
if (ch2 == ch) {
res = false;
goto done;
}
}
}
done:
rcu_read_unlock();

return res;
Expand Down Expand Up @@ -1891,30 +1895,78 @@ static bool srpt_disconnect_ch_sync(struct srpt_rdma_ch *ch)
return ret == 0;
}

static void srpt_set_enabled(struct srpt_port *sport, bool enabled)
__must_hold(&sport->mutex)
static void __srpt_close_all_ch(struct srpt_port *sport)
{
struct srpt_nexus *nexus;
struct srpt_rdma_ch *ch;

lockdep_assert_held(&sport->mutex);

if (sport->enabled == enabled)
return;
sport->enabled = enabled;
if (sport->enabled)
return;
list_for_each_entry(nexus, &sport->nexus_list, entry) {
list_for_each_entry(ch, &nexus->ch_list, list) {
if (srpt_disconnect_ch(ch) >= 0)
pr_info("Closing channel %s-%d because target %s_%d has been disabled\n",
ch->sess_name, ch->qp->qp_num,
sport->sdev->device->name, sport->port);
srpt_close_ch(ch);
}
}
}

/*
* Look up (i_port_id, t_port_id) in sport->nexus_list. Create an entry if
* it does not yet exist.
*/
static struct srpt_nexus *srpt_get_nexus(struct srpt_port *sport,
const u8 i_port_id[16],
const u8 t_port_id[16])
{
struct srpt_nexus *nexus = NULL, *tmp_nexus = NULL, *n;

again:
list_for_each_entry(ch, &sport->rch_list, list) {
if (ch->sport == sport) {
pr_info("%s: closing channel %s-%d\n",
sport->sdev->device->name, ch->sess_name,
ch->qp->qp_num);
if (srpt_disconnect_ch_sync(ch))
goto again;
for (;;) {
mutex_lock(&sport->mutex);
list_for_each_entry(n, &sport->nexus_list, entry) {
if (memcmp(n->i_port_id, i_port_id, 16) == 0 &&
memcmp(n->t_port_id, t_port_id, 16) == 0) {
nexus = n;
break;
}
}
if (!nexus && tmp_nexus) {
list_add_tail_rcu(&tmp_nexus->entry,
&sport->nexus_list);
swap(nexus, tmp_nexus);
}
mutex_unlock(&sport->mutex);

if (nexus)
break;
tmp_nexus = kzalloc(sizeof(*nexus), GFP_KERNEL);
if (!tmp_nexus) {
nexus = ERR_PTR(-ENOMEM);
break;
}
init_rcu_head(&tmp_nexus->rcu);
INIT_LIST_HEAD(&tmp_nexus->ch_list);
memcpy(tmp_nexus->i_port_id, i_port_id, 16);
memcpy(tmp_nexus->t_port_id, t_port_id, 16);
}

kfree(tmp_nexus);

return nexus;
}

static void srpt_set_enabled(struct srpt_port *sport, bool enabled)
__must_hold(&sport->mutex)
{
lockdep_assert_held(&sport->mutex);

if (sport->enabled == enabled)
return;
sport->enabled = enabled;
if (!enabled)
__srpt_close_all_ch(sport);
}

static void srpt_free_ch(struct kref *kref)
Expand Down Expand Up @@ -1984,11 +2036,12 @@ static int srpt_cm_req_recv(struct ib_cm_id *cm_id,
{
struct srpt_device *sdev = cm_id->context;
struct srpt_port *sport = &sdev->port[param->port - 1];
struct srpt_nexus *nexus;
struct srp_login_req *req;
struct srp_login_rsp *rsp;
struct srp_login_rej *rej;
struct ib_cm_rep_param *rep_param;
struct srpt_rdma_ch *ch, *tmp_ch;
struct srp_login_rsp *rsp = NULL;
struct srp_login_rej *rej = NULL;
struct ib_cm_rep_param *rep_param = NULL;
struct srpt_rdma_ch *ch;
char i_port_id[36];
u32 it_iu_len;
int i, ret = 0;
Expand All @@ -2007,6 +2060,13 @@ static int srpt_cm_req_recv(struct ib_cm_id *cm_id,
param->port, &sport->gid,
be16_to_cpu(param->primary_path->pkey));

nexus = srpt_get_nexus(sport, req->initiator_port_id,
req->target_port_id);
if (IS_ERR(nexus)) {
ret = PTR_ERR(nexus);
goto out;
}

rsp = kzalloc(sizeof(*rsp), GFP_KERNEL);
rej = kzalloc(sizeof(*rej), GFP_KERNEL);
rep_param = kzalloc(sizeof(*rep_param), GFP_KERNEL);
Expand Down Expand Up @@ -2036,29 +2096,22 @@ static int srpt_cm_req_recv(struct ib_cm_id *cm_id,
}

if ((req->req_flags & SRP_MTCH_ACTION) == SRP_MULTICHAN_SINGLE) {
struct srpt_rdma_ch *ch2;

rsp->rsp_flags = SRP_LOGIN_RSP_MULTICHAN_NO_CHAN;

mutex_lock(&sport->mutex);

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
&& param->listen_id == ch->sport->sdev->cm_id
&& ch->cm_id) {
if (srpt_disconnect_ch(ch) < 0)
continue;
pr_info("Relogin - closed existing channel %s\n",
ch->sess_name);
rsp->rsp_flags =
SRP_LOGIN_RSP_MULTICHAN_TERMINATED;
}
list_for_each_entry(ch2, &nexus->ch_list, list) {
if (srpt_disconnect_ch(ch2) < 0)
continue;
pr_info("Relogin - closed existing channel %s\n",
ch2->sess_name);
rsp->rsp_flags = SRP_LOGIN_RSP_MULTICHAN_TERMINATED;
}

mutex_unlock(&sport->mutex);

} else
} else {
rsp->rsp_flags = SRP_LOGIN_RSP_MULTICHAN_MAINTAINED;
}

if (*(__be64 *)req->target_port_id != cpu_to_be64(srpt_service_guid)
|| *(__be64 *)(req->target_port_id + 8) !=
Expand All @@ -2083,10 +2136,9 @@ static int srpt_cm_req_recv(struct ib_cm_id *cm_id,
init_rcu_head(&ch->rcu);
kref_init(&ch->kref);
ch->pkey = be16_to_cpu(param->primary_path->pkey);
ch->nexus = nexus;
ch->zw_cqe.done = srpt_zerolength_write_done;
INIT_WORK(&ch->release_work, srpt_release_channel_work);
memcpy(ch->i_port_id, req->initiator_port_id, 16);
memcpy(ch->t_port_id, req->target_port_id, 16);
ch->sport = &sdev->port[param->port - 1];
ch->cm_id = cm_id;
cm_id->context = ch;
Expand Down Expand Up @@ -2147,8 +2199,8 @@ static int srpt_cm_req_recv(struct ib_cm_id *cm_id,
srpt_format_guid(ch->sess_name, sizeof(ch->sess_name),
&param->primary_path->dgid.global.interface_id);
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)));
be64_to_cpu(*(__be64 *)nexus->i_port_id),
be64_to_cpu(*(__be64 *)(nexus->i_port_id + 8)));

pr_debug("registering session %s\n", ch->sess_name);

Expand Down Expand Up @@ -2208,7 +2260,7 @@ static int srpt_cm_req_recv(struct ib_cm_id *cm_id,
}

mutex_lock(&sport->mutex);
list_add_tail_rcu(&ch->list, &sport->rch_list);
list_add_tail_rcu(&ch->list, &nexus->ch_list);
mutex_unlock(&sport->mutex);

goto out;
Expand Down Expand Up @@ -2560,24 +2612,56 @@ static void srpt_refresh_port_work(struct work_struct *work)
srpt_refresh_port(sport);
}

static bool srpt_ch_list_empty(struct srpt_port *sport)
{
struct srpt_nexus *nexus;
bool res = true;

rcu_read_lock();
list_for_each_entry(nexus, &sport->nexus_list, entry)
if (!list_empty(&nexus->ch_list))
res = false;
rcu_read_unlock();

return res;
}

/**
* srpt_release_sport - disable login and wait for associated channels
* @sport: SRPT HCA port.
*/
static int srpt_release_sport(struct srpt_port *sport)
{
int res;
struct srpt_nexus *nexus, *next_n;
struct srpt_rdma_ch *ch;

WARN_ON_ONCE(irqs_disabled());

mutex_lock(&sport->mutex);
srpt_set_enabled(sport, false);
mutex_unlock(&sport->mutex);

res = wait_event_interruptible(sport->ch_releaseQ,
list_empty_careful(&sport->rch_list));
if (res)
pr_err("%s: interrupted.\n", __func__);
while (wait_event_timeout(sport->ch_releaseQ,
srpt_ch_list_empty(sport), 5 * HZ) <= 0) {
pr_info("%s_%d: waiting for session unregistration ...\n",
sport->sdev->device->name, sport->port);
rcu_read_lock();
list_for_each_entry(nexus, &sport->nexus_list, entry) {
list_for_each_entry(ch, &nexus->ch_list, list) {
pr_info("%s-%d: state %s\n",
ch->sess_name, ch->qp->qp_num,
get_ch_state_name(ch->state));
}
}
rcu_read_unlock();
}

mutex_lock(&sport->mutex);
list_for_each_entry_safe(nexus, next_n, &sport->nexus_list, entry) {
list_del(&nexus->entry);
kfree_rcu(nexus, rcu);
}
mutex_unlock(&sport->mutex);

return 0;
}
Expand Down Expand Up @@ -2744,7 +2828,7 @@ 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_LIST_HEAD(&sport->nexus_list);
init_waitqueue_head(&sport->ch_releaseQ);
mutex_init(&sport->mutex);
sport->sdev = sdev;
Expand Down
34 changes: 25 additions & 9 deletions drivers/infiniband/ulp/srpt/ib_srpt.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -54,6 +54,8 @@
*/
#define SRP_SERVICE_NAME_PREFIX "SRP.T10:"

struct srpt_nexus;

enum {
/*
* SRP IOControllerProfile attributes for SRP target ports that have
Expand Down Expand Up @@ -240,6 +242,7 @@ enum rdma_ch_state {

/**
* struct srpt_rdma_ch - RDMA channel
* @nexus: I_T nexus this channel is associated with.
* @cm_id: IB CM ID associated with the channel.
* @qp: IB queue pair used for communicating over this channel.
* @cq: IB completion queue for this channel.
Expand All @@ -251,8 +254,6 @@ enum rdma_ch_state {
* @sq_wr_avail: number of work requests available in the send queue.
* @sport: pointer to the information of the HCA port used by this
* channel.
* @i_port_id: 128-bit initiator port identifier copied from SRP_LOGIN_REQ.
* @t_port_id: 128-bit target port identifier copied from SRP_LOGIN_REQ.
* @max_ti_iu_len: maximum target-to-initiator information unit length.
* @req_lim: request limit: maximum number of requests that may be sent
* by the initiator without having received a response.
Expand All @@ -262,7 +263,7 @@ 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 in srpt_port.rch_list.
* @list: Node in srpt_nexus.ch_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.
Expand All @@ -272,6 +273,7 @@ enum rdma_ch_state {
* @release_work: Allows scheduling of srpt_release_channel().
*/
struct srpt_rdma_ch {
struct srpt_nexus *nexus;
struct ib_cm_id *cm_id;
struct ib_qp *qp;
struct ib_cq *cq;
Expand All @@ -282,8 +284,6 @@ struct srpt_rdma_ch {
u32 max_rsp_size;
atomic_t sq_wr_avail;
struct srpt_port *sport;
u8 i_port_id[16];
u8 t_port_id[16];
int max_ti_iu_len;
atomic_t req_lim;
atomic_t req_lim_delta;
Expand All @@ -300,6 +300,22 @@ struct srpt_rdma_ch {
struct work_struct release_work;
};

/**
* struct srpt_nexus - I_T nexus
* @rcu: RCU head for this data structure.
* @entry: srpt_port.nexus_list list node.
* @ch_list: struct srpt_rdma_ch list. Protected by srpt_port.mutex.
* @i_port_id: 128-bit initiator port identifier copied from SRP_LOGIN_REQ.
* @t_port_id: 128-bit target port identifier copied from SRP_LOGIN_REQ.
*/
struct srpt_nexus {
struct rcu_head rcu;
struct list_head entry;
struct list_head ch_list;
u8 i_port_id[16];
u8 t_port_id[16];
};

/**
* struct srpt_port_attib - attributes for SRPT port
* @srp_max_rdma_size: Maximum size of SRP RDMA transfers for new connections.
Expand Down Expand Up @@ -332,9 +348,9 @@ 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.
* @ch_releaseQ: Enables waiting for removal from nexus_list.
* @mutex: Protects nexus_list.
* @nexus_list: Nexus list. See also srpt_nexus.entry.
*/
struct srpt_port {
struct srpt_device *sdev;
Expand All @@ -354,7 +370,7 @@ struct srpt_port {
struct srpt_port_attrib port_attrib;
wait_queue_head_t ch_releaseQ;
struct mutex mutex;
struct list_head rch_list;
struct list_head nexus_list;
};

/**
Expand Down

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