/**
* ipath_ruc_loopback - handle UC and RC lookback requests
* @sqp: the sending QP
*
* This is called from ipath_do_send() to
* forward a WQE addressed to the same HCA.
* Note that although we are single threaded due to the tasklet, we still
* have to protect against post_send(). We don't have to worry about
* receive interrupts since this is a connected protocol and all packets
* will pass through here.
*/
static void ipath_ruc_loopback(struct ipath_qp *sqp)
{
struct ipath_ibdev *dev = to_idev(sqp->ibqp.device);
struct ipath_qp *qp;
struct ipath_swqe *wqe;
struct ipath_sge *sge;
unsigned long flags;
struct ib_wc wc;
u64 sdata;
atomic64_t *maddr;
enum ib_wc_status send_status;
/*
* Note that we check the responder QP state after
* checking the requester's state.
*/
qp = ipath_lookup_qpn(&dev->qp_table, sqp->remote_qpn);
spin_lock_irqsave(&sqp->s_lock, flags);
/* Return if we are already busy processing a work request. */
if ((sqp->s_flags & (IPATH_S_BUSY | IPATH_S_ANY_WAIT)) ||
!(ib_ipath_state_ops[sqp->state] & IPATH_PROCESS_OR_FLUSH_SEND))
goto unlock;
sqp->s_flags |= IPATH_S_BUSY;
again:
if (sqp->s_last == sqp->s_head)
goto clr_busy;
wqe = get_swqe_ptr(sqp, sqp->s_last);
/* Return if it is not OK to start a new work reqeust. */
if (!(ib_ipath_state_ops[sqp->state] & IPATH_PROCESS_NEXT_SEND_OK)) {
if (!(ib_ipath_state_ops[sqp->state] & IPATH_FLUSH_SEND))
goto clr_busy;
/* We are in the error state, flush the work request. */
send_status = IB_WC_WR_FLUSH_ERR;
goto flush_send;
}
/*
* We can rely on the entry not changing without the s_lock
* being held until we update s_last.
* We increment s_cur to indicate s_last is in progress.
*/
if (sqp->s_last == sqp->s_cur) {
if (++sqp->s_cur >= sqp->s_size)
sqp->s_cur = 0;
}
spin_unlock_irqrestore(&sqp->s_lock, flags);
if (!qp || !(ib_ipath_state_ops[qp->state] & IPATH_PROCESS_RECV_OK)) {
dev->n_pkt_drops++;
/*
* For RC, the requester would timeout and retry so
* shortcut the timeouts and just signal too many retries.
*/
if (sqp->ibqp.qp_type == IB_QPT_RC)
send_status = IB_WC_RETRY_EXC_ERR;
else
send_status = IB_WC_SUCCESS;
goto serr;
}
memset(&wc, 0, sizeof wc);
send_status = IB_WC_SUCCESS;
sqp->s_sge.sge = wqe->sg_list[0];
sqp->s_sge.sg_list = wqe->sg_list + 1;
sqp->s_sge.num_sge = wqe->wr.num_sge;
sqp->s_len = wqe->length;
switch (wqe->wr.opcode) {
case IB_WR_SEND_WITH_IMM:
wc.wc_flags = IB_WC_WITH_IMM;
wc.imm_data = wqe->wr.ex.imm_data;
/* FALLTHROUGH */
case IB_WR_SEND:
if (!ipath_get_rwqe(qp, 0))
goto rnr_nak;
break;
case IB_WR_RDMA_WRITE_WITH_IMM:
if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_WRITE)))
goto inv_err;
wc.wc_flags = IB_WC_WITH_IMM;
wc.imm_data = wqe->wr.ex.imm_data;
if (!ipath_get_rwqe(qp, 1))
goto rnr_nak;
/* FALLTHROUGH */
case IB_WR_RDMA_WRITE:
if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_WRITE)))
goto inv_err;
if (wqe->length == 0)
break;
if (unlikely(!ipath_rkey_ok(qp, &qp->r_sge, wqe->length,
wqe->wr.wr.rdma.remote_addr,
wqe->wr.wr.rdma.rkey,
IB_ACCESS_REMOTE_WRITE)))
goto acc_err;
break;
case IB_WR_RDMA_READ:
if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_READ)))
goto inv_err;
if (unlikely(!ipath_rkey_ok(qp, &sqp->s_sge, wqe->length,
wqe->wr.wr.rdma.remote_addr,
wqe->wr.wr.rdma.rkey,
IB_ACCESS_REMOTE_READ)))
goto acc_err;
qp->r_sge.sge = wqe->sg_list[0];
qp->r_sge.sg_list = wqe->sg_list + 1;
qp->r_sge.num_sge = wqe->wr.num_sge;
break;
case IB_WR_ATOMIC_CMP_AND_SWP:
case IB_WR_ATOMIC_FETCH_AND_ADD:
if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_ATOMIC)))
goto inv_err;
if (unlikely(!ipath_rkey_ok(qp, &qp->r_sge, sizeof(u64),
wqe->wr.wr.atomic.remote_addr,
wqe->wr.wr.atomic.rkey,
IB_ACCESS_REMOTE_ATOMIC)))
goto acc_err;
/* Perform atomic OP and save result. */
maddr = (atomic64_t *) qp->r_sge.sge.vaddr;
sdata = wqe->wr.wr.atomic.compare_add;
*(u64 *) sqp->s_sge.sge.vaddr =
(wqe->wr.opcode == IB_WR_ATOMIC_FETCH_AND_ADD) ?
(u64) atomic64_add_return(sdata, maddr) - sdata :
(u64) cmpxchg((u64 *) qp->r_sge.sge.vaddr,
sdata, wqe->wr.wr.atomic.swap);
goto send_comp;
default:
send_status = IB_WC_LOC_QP_OP_ERR;
goto serr;
}
sge = &sqp->s_sge.sge;
while (sqp->s_len) {
u32 len = sqp->s_len;
if (len > sge->length)
len = sge->length;
if (len > sge->sge_length)
len = sge->sge_length;
BUG_ON(len == 0);
ipath_copy_sge(&qp->r_sge, sge->vaddr, len);
sge->vaddr += len;
sge->length -= len;
sge->sge_length -= len;
if (sge->sge_length == 0) {
if (--sqp->s_sge.num_sge)
*sge = *sqp->s_sge.sg_list++;
} else if (sge->length == 0 && sge->mr != NULL) {
if (++sge->n >= IPATH_SEGSZ) {
if (++sge->m >= sge->mr->mapsz)
break;
sge->n = 0;
}
sge->vaddr =
sge->mr->map[sge->m]->segs[sge->n].vaddr;
sge->length =
sge->mr->map[sge->m]->segs[sge->n].length;
}
sqp->s_len -= len;
}
if (!test_and_clear_bit(IPATH_R_WRID_VALID, &qp->r_aflags))
goto send_comp;
if (wqe->wr.opcode == IB_WR_RDMA_WRITE_WITH_IMM)
wc.opcode = IB_WC_RECV_RDMA_WITH_IMM;
else
wc.opcode = IB_WC_RECV;
wc.wr_id = qp->r_wr_id;
wc.status = IB_WC_SUCCESS;
wc.byte_len = wqe->length;
wc.qp = &qp->ibqp;
wc.src_qp = qp->remote_qpn;
wc.slid = qp->remote_ah_attr.dlid;
wc.sl = qp->remote_ah_attr.sl;
wc.port_num = 1;
/* Signal completion event if the solicited bit is set. */
ipath_cq_enter(to_icq(qp->ibqp.recv_cq), &wc,
wqe->wr.send_flags & IB_SEND_SOLICITED);
send_comp:
spin_lock_irqsave(&sqp->s_lock, flags);
flush_send:
sqp->s_rnr_retry = sqp->s_rnr_retry_cnt;
ipath_send_complete(sqp, wqe, send_status);
goto again;
rnr_nak:
/* Handle RNR NAK */
if (qp->ibqp.qp_type == IB_QPT_UC)
goto send_comp;
/*
* Note: we don't need the s_lock held since the BUSY flag
* makes this single threaded.
*/
if (sqp->s_rnr_retry == 0) {
send_status = IB_WC_RNR_RETRY_EXC_ERR;
goto serr;
}
if (sqp->s_rnr_retry_cnt < 7)
sqp->s_rnr_retry--;
spin_lock_irqsave(&sqp->s_lock, flags);
if (!(ib_ipath_state_ops[sqp->state] & IPATH_PROCESS_RECV_OK))
goto clr_busy;
sqp->s_flags |= IPATH_S_WAITING;
dev->n_rnr_naks++;
sqp->s_rnr_timeout = ib_ipath_rnr_table[qp->r_min_rnr_timer];
ipath_insert_rnr_queue(sqp);
goto clr_busy;
inv_err:
send_status = IB_WC_REM_INV_REQ_ERR;
wc.status = IB_WC_LOC_QP_OP_ERR;
goto err;
acc_err:
send_status = IB_WC_REM_ACCESS_ERR;
wc.status = IB_WC_LOC_PROT_ERR;
err:
/* responder goes to error state */
ipath_rc_error(qp, wc.status);
serr:
spin_lock_irqsave(&sqp->s_lock, flags);
ipath_send_complete(sqp, wqe, send_status);
if (sqp->ibqp.qp_type == IB_QPT_RC) {
int lastwqe = ipath_error_qp(sqp, IB_WC_WR_FLUSH_ERR);
sqp->s_flags &= ~IPATH_S_BUSY;
spin_unlock_irqrestore(&sqp->s_lock, flags);
if (lastwqe) {
struct ib_event ev;
ev.device = sqp->ibqp.device;
ev.element.qp = &sqp->ibqp;
ev.event = IB_EVENT_QP_LAST_WQE_REACHED;
sqp->ibqp.event_handler(&ev, sqp->ibqp.qp_context);
}
goto done;
}
clr_busy:
sqp->s_flags &= ~IPATH_S_BUSY;
unlock:
spin_unlock_irqrestore(&sqp->s_lock, flags);
done:
if (qp && atomic_dec_and_test(&qp->refcount))
wake_up(&qp->wait);
}
static void ipath_ruc_loopback(struct ipath_qp *sqp)
{
struct ipath_ibdev *dev = to_idev(sqp->ibqp.device);
struct ipath_qp *qp;
struct ipath_swqe *wqe;
struct ipath_sge *sge;
unsigned long flags;
struct ib_wc wc;
u64 sdata;
atomic64_t *maddr;
enum ib_wc_status send_status;
qp = ipath_lookup_qpn(&dev->qp_table, sqp->remote_qpn);
spin_lock_irqsave(&sqp->s_lock, flags);
if ((sqp->s_flags & (IPATH_S_BUSY | IPATH_S_ANY_WAIT)) ||
!(ib_ipath_state_ops[sqp->state] & IPATH_PROCESS_OR_FLUSH_SEND))
goto unlock;
sqp->s_flags |= IPATH_S_BUSY;
again:
if (sqp->s_last == sqp->s_head)
goto clr_busy;
wqe = get_swqe_ptr(sqp, sqp->s_last);
if (!(ib_ipath_state_ops[sqp->state] & IPATH_PROCESS_NEXT_SEND_OK)) {
if (!(ib_ipath_state_ops[sqp->state] & IPATH_FLUSH_SEND))
goto clr_busy;
send_status = IB_WC_WR_FLUSH_ERR;
goto flush_send;
}
if (sqp->s_last == sqp->s_cur) {
if (++sqp->s_cur >= sqp->s_size)
sqp->s_cur = 0;
}
spin_unlock_irqrestore(&sqp->s_lock, flags);
if (!qp || !(ib_ipath_state_ops[qp->state] & IPATH_PROCESS_RECV_OK)) {
dev->n_pkt_drops++;
if (sqp->ibqp.qp_type == IB_QPT_RC)
send_status = IB_WC_RETRY_EXC_ERR;
else
send_status = IB_WC_SUCCESS;
goto serr;
}
memset(&wc, 0, sizeof wc);
send_status = IB_WC_SUCCESS;
sqp->s_sge.sge = wqe->sg_list[0];
sqp->s_sge.sg_list = wqe->sg_list + 1;
sqp->s_sge.num_sge = wqe->wr.num_sge;
sqp->s_len = wqe->length;
switch (wqe->wr.opcode) {
case IB_WR_SEND_WITH_IMM:
wc.wc_flags = IB_WC_WITH_IMM;
wc.ex.imm_data = wqe->wr.ex.imm_data;
case IB_WR_SEND:
if (!ipath_get_rwqe(qp, 0))
goto rnr_nak;
break;
case IB_WR_RDMA_WRITE_WITH_IMM:
if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_WRITE)))
goto inv_err;
wc.wc_flags = IB_WC_WITH_IMM;
wc.ex.imm_data = wqe->wr.ex.imm_data;
if (!ipath_get_rwqe(qp, 1))
goto rnr_nak;
case IB_WR_RDMA_WRITE:
if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_WRITE)))
goto inv_err;
if (wqe->length == 0)
break;
if (unlikely(!ipath_rkey_ok(qp, &qp->r_sge, wqe->length,
wqe->wr.wr.rdma.remote_addr,
wqe->wr.wr.rdma.rkey,
IB_ACCESS_REMOTE_WRITE)))
goto acc_err;
break;
case IB_WR_RDMA_READ:
if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_READ)))
goto inv_err;
if (unlikely(!ipath_rkey_ok(qp, &sqp->s_sge, wqe->length,
wqe->wr.wr.rdma.remote_addr,
wqe->wr.wr.rdma.rkey,
IB_ACCESS_REMOTE_READ)))
goto acc_err;
qp->r_sge.sge = wqe->sg_list[0];
qp->r_sge.sg_list = wqe->sg_list + 1;
qp->r_sge.num_sge = wqe->wr.num_sge;
break;
case IB_WR_ATOMIC_CMP_AND_SWP:
case IB_WR_ATOMIC_FETCH_AND_ADD:
if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_ATOMIC)))
goto inv_err;
if (unlikely(!ipath_rkey_ok(qp, &qp->r_sge, sizeof(u64),
wqe->wr.wr.atomic.remote_addr,
wqe->wr.wr.atomic.rkey,
IB_ACCESS_REMOTE_ATOMIC)))
goto acc_err;
maddr = (atomic64_t *) qp->r_sge.sge.vaddr;
sdata = wqe->wr.wr.atomic.compare_add;
*(u64 *) sqp->s_sge.sge.vaddr =
(wqe->wr.opcode == IB_WR_ATOMIC_FETCH_AND_ADD) ?
(u64) atomic64_add_return(sdata, maddr) - sdata :
(u64) cmpxchg((u64 *) qp->r_sge.sge.vaddr,
sdata, wqe->wr.wr.atomic.swap);
goto send_comp;
default:
send_status = IB_WC_LOC_QP_OP_ERR;
goto serr;
}
sge = &sqp->s_sge.sge;
while (sqp->s_len) {
u32 len = sqp->s_len;
if (len > sge->length)
len = sge->length;
if (len > sge->sge_length)
len = sge->sge_length;
BUG_ON(len == 0);
ipath_copy_sge(&qp->r_sge, sge->vaddr, len);
sge->vaddr += len;
sge->length -= len;
sge->sge_length -= len;
if (sge->sge_length == 0) {
if (--sqp->s_sge.num_sge)
*sge = *sqp->s_sge.sg_list++;
} else if (sge->length == 0 && sge->mr != NULL) {
if (++sge->n >= IPATH_SEGSZ) {
if (++sge->m >= sge->mr->mapsz)
break;
sge->n = 0;
}
sge->vaddr =
sge->mr->map[sge->m]->segs[sge->n].vaddr;
sge->length =
sge->mr->map[sge->m]->segs[sge->n].length;
}
sqp->s_len -= len;
}
if (!test_and_clear_bit(IPATH_R_WRID_VALID, &qp->r_aflags))
goto send_comp;
if (wqe->wr.opcode == IB_WR_RDMA_WRITE_WITH_IMM)
wc.opcode = IB_WC_RECV_RDMA_WITH_IMM;
else
wc.opcode = IB_WC_RECV;
wc.wr_id = qp->r_wr_id;
wc.status = IB_WC_SUCCESS;
wc.byte_len = wqe->length;
wc.qp = &qp->ibqp;
wc.src_qp = qp->remote_qpn;
wc.slid = qp->remote_ah_attr.dlid;
wc.sl = qp->remote_ah_attr.sl;
wc.port_num = 1;
ipath_cq_enter(to_icq(qp->ibqp.recv_cq), &wc,
wqe->wr.send_flags & IB_SEND_SOLICITED);
send_comp:
spin_lock_irqsave(&sqp->s_lock, flags);
flush_send:
sqp->s_rnr_retry = sqp->s_rnr_retry_cnt;
ipath_send_complete(sqp, wqe, send_status);
goto again;
rnr_nak:
if (qp->ibqp.qp_type == IB_QPT_UC)
goto send_comp;
if (sqp->s_rnr_retry == 0) {
send_status = IB_WC_RNR_RETRY_EXC_ERR;
goto serr;
}
if (sqp->s_rnr_retry_cnt < 7)
sqp->s_rnr_retry--;
spin_lock_irqsave(&sqp->s_lock, flags);
if (!(ib_ipath_state_ops[sqp->state] & IPATH_PROCESS_RECV_OK))
goto clr_busy;
sqp->s_flags |= IPATH_S_WAITING;
dev->n_rnr_naks++;
sqp->s_rnr_timeout = ib_ipath_rnr_table[qp->r_min_rnr_timer];
ipath_insert_rnr_queue(sqp);
goto clr_busy;
inv_err:
send_status = IB_WC_REM_INV_REQ_ERR;
wc.status = IB_WC_LOC_QP_OP_ERR;
goto err;
acc_err:
send_status = IB_WC_REM_ACCESS_ERR;
wc.status = IB_WC_LOC_PROT_ERR;
err:
ipath_rc_error(qp, wc.status);
serr:
spin_lock_irqsave(&sqp->s_lock, flags);
ipath_send_complete(sqp, wqe, send_status);
if (sqp->ibqp.qp_type == IB_QPT_RC) {
int lastwqe = ipath_error_qp(sqp, IB_WC_WR_FLUSH_ERR);
sqp->s_flags &= ~IPATH_S_BUSY;
spin_unlock_irqrestore(&sqp->s_lock, flags);
if (lastwqe) {
struct ib_event ev;
ev.device = sqp->ibqp.device;
ev.element.qp = &sqp->ibqp;
ev.event = IB_EVENT_QP_LAST_WQE_REACHED;
sqp->ibqp.event_handler(&ev, sqp->ibqp.qp_context);
}
goto done;
}
clr_busy:
sqp->s_flags &= ~IPATH_S_BUSY;
unlock:
spin_unlock_irqrestore(&sqp->s_lock, flags);
done:
if (qp && atomic_dec_and_test(&qp->refcount))
wake_up(&qp->wait);
}