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linux/drivers/infiniband/hw/qib/qib_ruc.c
Mike Marciniszyn 6a82649f21 IB/qib: Avoid returning EBUSY from MR deregister 
A timing issue can occur where qib_mr_dereg can return -EBUSY if the
MR use count is not zero.

This can occur if the MR is de-registered while RDMA read response
packets are being progressed from the SDMA ring.  The suspicion is
that the peer sent an RDMA read request, which has already been copied
across to the peer.  The peer sees the completion of his request and
then communicates to the responder that the MR is not needed any
longer.  The responder tries to de-register the MR, catching some
responses remaining in the SDMA ring holding the MR use count.

The code now uses a get/put paradigm to track MR use counts and
coordinates with the MR de-registration process using a completion
when the count has reached zero.  A timeout on the delay is in place
to catch other EBUSY issues.

The reference count protocol is as follows:
- The return to the user counts as 1
- A reference from the lk_table or the qib_ibdev counts as 1.
- Transient I/O operations increase/decrease as necessary

A lot of code duplication has been folded into the new routines
init_qib_mregion() and deinit_qib_mregion().  Additionally, explicit
initialization of fields to zero is now handled by kzalloc().

Also, duplicated code 'while.*num_sge' that decrements reference
counts have been consolidated in qib_put_ss().

Reviewed-by: Ramkrishna Vepa <ramkrishna.vepa@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
2012-07-08 18:05:19 -07:00

819 lines
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/*
* Copyright (c) 2006, 2007, 2008, 2009 QLogic Corporation. All rights reserved.
* Copyright (c) 2005, 2006 PathScale, 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/spinlock.h>
#include "qib.h"
#include "qib_mad.h"
/*
* Convert the AETH RNR timeout code into the number of microseconds.
*/
const u32 ib_qib_rnr_table[32] = {
655360, /* 00: 655.36 */
10, /* 01: .01 */
20, /* 02 .02 */
30, /* 03: .03 */
40, /* 04: .04 */
60, /* 05: .06 */
80, /* 06: .08 */
120, /* 07: .12 */
160, /* 08: .16 */
240, /* 09: .24 */
320, /* 0A: .32 */
480, /* 0B: .48 */
640, /* 0C: .64 */
960, /* 0D: .96 */
1280, /* 0E: 1.28 */
1920, /* 0F: 1.92 */
2560, /* 10: 2.56 */
3840, /* 11: 3.84 */
5120, /* 12: 5.12 */
7680, /* 13: 7.68 */
10240, /* 14: 10.24 */
15360, /* 15: 15.36 */
20480, /* 16: 20.48 */
30720, /* 17: 30.72 */
40960, /* 18: 40.96 */
61440, /* 19: 61.44 */
81920, /* 1A: 81.92 */
122880, /* 1B: 122.88 */
163840, /* 1C: 163.84 */
245760, /* 1D: 245.76 */
327680, /* 1E: 327.68 */
491520 /* 1F: 491.52 */
};
/*
* Validate a RWQE and fill in the SGE state.
* Return 1 if OK.
*/
static int qib_init_sge(struct qib_qp *qp, struct qib_rwqe *wqe)
{
int i, j, ret;
struct ib_wc wc;
struct qib_lkey_table *rkt;
struct qib_pd *pd;
struct qib_sge_state *ss;
rkt = &to_idev(qp->ibqp.device)->lk_table;
pd = to_ipd(qp->ibqp.srq ? qp->ibqp.srq->pd : qp->ibqp.pd);
ss = &qp->r_sge;
ss->sg_list = qp->r_sg_list;
qp->r_len = 0;
for (i = j = 0; i < wqe->num_sge; i++) {
if (wqe->sg_list[i].length == 0)
continue;
/* Check LKEY */
if (!qib_lkey_ok(rkt, pd, j ? &ss->sg_list[j - 1] : &ss->sge,
&wqe->sg_list[i], IB_ACCESS_LOCAL_WRITE))
goto bad_lkey;
qp->r_len += wqe->sg_list[i].length;
j++;
}
ss->num_sge = j;
ss->total_len = qp->r_len;
ret = 1;
goto bail;
bad_lkey:
while (j) {
struct qib_sge *sge = --j ? &ss->sg_list[j - 1] : &ss->sge;
qib_put_mr(sge->mr);
}
ss->num_sge = 0;
memset(&wc, 0, sizeof(wc));
wc.wr_id = wqe->wr_id;
wc.status = IB_WC_LOC_PROT_ERR;
wc.opcode = IB_WC_RECV;
wc.qp = &qp->ibqp;
/* Signal solicited completion event. */
qib_cq_enter(to_icq(qp->ibqp.recv_cq), &wc, 1);
ret = 0;
bail:
return ret;
}
/**
* qib_get_rwqe - copy the next RWQE into the QP's RWQE
* @qp: the QP
* @wr_id_only: update qp->r_wr_id only, not qp->r_sge
*
* Return -1 if there is a local error, 0 if no RWQE is available,
* otherwise return 1.
*
* Can be called from interrupt level.
*/
int qib_get_rwqe(struct qib_qp *qp, int wr_id_only)
{
unsigned long flags;
struct qib_rq *rq;
struct qib_rwq *wq;
struct qib_srq *srq;
struct qib_rwqe *wqe;
void (*handler)(struct ib_event *, void *);
u32 tail;
int ret;
if (qp->ibqp.srq) {
srq = to_isrq(qp->ibqp.srq);
handler = srq->ibsrq.event_handler;
rq = &srq->rq;
} else {
srq = NULL;
handler = NULL;
rq = &qp->r_rq;
}
spin_lock_irqsave(&rq->lock, flags);
if (!(ib_qib_state_ops[qp->state] & QIB_PROCESS_RECV_OK)) {
ret = 0;
goto unlock;
}
wq = rq->wq;
tail = wq->tail;
/* Validate tail before using it since it is user writable. */
if (tail >= rq->size)
tail = 0;
if (unlikely(tail == wq->head)) {
ret = 0;
goto unlock;
}
/* Make sure entry is read after head index is read. */
smp_rmb();
wqe = get_rwqe_ptr(rq, tail);
/*
* Even though we update the tail index in memory, the verbs
* consumer is not supposed to post more entries until a
* completion is generated.
*/
if (++tail >= rq->size)
tail = 0;
wq->tail = tail;
if (!wr_id_only && !qib_init_sge(qp, wqe)) {
ret = -1;
goto unlock;
}
qp->r_wr_id = wqe->wr_id;
ret = 1;
set_bit(QIB_R_WRID_VALID, &qp->r_aflags);
if (handler) {
u32 n;
/*
* Validate head pointer value and compute
* the number of remaining WQEs.
*/
n = wq->head;
if (n >= rq->size)
n = 0;
if (n < tail)
n += rq->size - tail;
else
n -= tail;
if (n < srq->limit) {
struct ib_event ev;
srq->limit = 0;
spin_unlock_irqrestore(&rq->lock, flags);
ev.device = qp->ibqp.device;
ev.element.srq = qp->ibqp.srq;
ev.event = IB_EVENT_SRQ_LIMIT_REACHED;
handler(&ev, srq->ibsrq.srq_context);
goto bail;
}
}
unlock:
spin_unlock_irqrestore(&rq->lock, flags);
bail:
return ret;
}
/*
* Switch to alternate path.
* The QP s_lock should be held and interrupts disabled.
*/
void qib_migrate_qp(struct qib_qp *qp)
{
struct ib_event ev;
qp->s_mig_state = IB_MIG_MIGRATED;
qp->remote_ah_attr = qp->alt_ah_attr;
qp->port_num = qp->alt_ah_attr.port_num;
qp->s_pkey_index = qp->s_alt_pkey_index;
ev.device = qp->ibqp.device;
ev.element.qp = &qp->ibqp;
ev.event = IB_EVENT_PATH_MIG;
qp->ibqp.event_handler(&ev, qp->ibqp.qp_context);
}
static __be64 get_sguid(struct qib_ibport *ibp, unsigned index)
{
if (!index) {
struct qib_pportdata *ppd = ppd_from_ibp(ibp);
return ppd->guid;
} else
return ibp->guids[index - 1];
}
static int gid_ok(union ib_gid *gid, __be64 gid_prefix, __be64 id)
{
return (gid->global.interface_id == id &&
(gid->global.subnet_prefix == gid_prefix ||
gid->global.subnet_prefix == IB_DEFAULT_GID_PREFIX));
}
/*
*
* This should be called with the QP r_lock held.
*
* The s_lock will be acquired around the qib_migrate_qp() call.
*/
int qib_ruc_check_hdr(struct qib_ibport *ibp, struct qib_ib_header *hdr,
int has_grh, struct qib_qp *qp, u32 bth0)
{
__be64 guid;
unsigned long flags;
if (qp->s_mig_state == IB_MIG_ARMED && (bth0 & IB_BTH_MIG_REQ)) {
if (!has_grh) {
if (qp->alt_ah_attr.ah_flags & IB_AH_GRH)
goto err;
} else {
if (!(qp->alt_ah_attr.ah_flags & IB_AH_GRH))
goto err;
guid = get_sguid(ibp, qp->alt_ah_attr.grh.sgid_index);
if (!gid_ok(&hdr->u.l.grh.dgid, ibp->gid_prefix, guid))
goto err;
if (!gid_ok(&hdr->u.l.grh.sgid,
qp->alt_ah_attr.grh.dgid.global.subnet_prefix,
qp->alt_ah_attr.grh.dgid.global.interface_id))
goto err;
}
if (!qib_pkey_ok((u16)bth0,
qib_get_pkey(ibp, qp->s_alt_pkey_index))) {
qib_bad_pqkey(ibp, IB_NOTICE_TRAP_BAD_PKEY,
(u16)bth0,
(be16_to_cpu(hdr->lrh[0]) >> 4) & 0xF,
0, qp->ibqp.qp_num,
hdr->lrh[3], hdr->lrh[1]);
goto err;
}
/* Validate the SLID. See Ch. 9.6.1.5 and 17.2.8 */
if (be16_to_cpu(hdr->lrh[3]) != qp->alt_ah_attr.dlid ||
ppd_from_ibp(ibp)->port != qp->alt_ah_attr.port_num)
goto err;
spin_lock_irqsave(&qp->s_lock, flags);
qib_migrate_qp(qp);
spin_unlock_irqrestore(&qp->s_lock, flags);
} else {
if (!has_grh) {
if (qp->remote_ah_attr.ah_flags & IB_AH_GRH)
goto err;
} else {
if (!(qp->remote_ah_attr.ah_flags & IB_AH_GRH))
goto err;
guid = get_sguid(ibp,
qp->remote_ah_attr.grh.sgid_index);
if (!gid_ok(&hdr->u.l.grh.dgid, ibp->gid_prefix, guid))
goto err;
if (!gid_ok(&hdr->u.l.grh.sgid,
qp->remote_ah_attr.grh.dgid.global.subnet_prefix,
qp->remote_ah_attr.grh.dgid.global.interface_id))
goto err;
}
if (!qib_pkey_ok((u16)bth0,
qib_get_pkey(ibp, qp->s_pkey_index))) {
qib_bad_pqkey(ibp, IB_NOTICE_TRAP_BAD_PKEY,
(u16)bth0,
(be16_to_cpu(hdr->lrh[0]) >> 4) & 0xF,
0, qp->ibqp.qp_num,
hdr->lrh[3], hdr->lrh[1]);
goto err;
}
/* Validate the SLID. See Ch. 9.6.1.5 */
if (be16_to_cpu(hdr->lrh[3]) != qp->remote_ah_attr.dlid ||
ppd_from_ibp(ibp)->port != qp->port_num)
goto err;
if (qp->s_mig_state == IB_MIG_REARM &&
!(bth0 & IB_BTH_MIG_REQ))
qp->s_mig_state = IB_MIG_ARMED;
}
return 0;
err:
return 1;
}
/**
* qib_ruc_loopback - handle UC and RC lookback requests
* @sqp: the sending QP
*
* This is called from qib_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 qib_ruc_loopback(struct qib_qp *sqp)
{
struct qib_ibport *ibp = to_iport(sqp->ibqp.device, sqp->port_num);
struct qib_qp *qp;
struct qib_swqe *wqe;
struct qib_sge *sge;
unsigned long flags;
struct ib_wc wc;
u64 sdata;
atomic64_t *maddr;
enum ib_wc_status send_status;
int release;
int ret;
/*
* Note that we check the responder QP state after
* checking the requester's state.
*/
qp = qib_lookup_qpn(ibp, sqp->remote_qpn);
spin_lock_irqsave(&sqp->s_lock, flags);
/* Return if we are already busy processing a work request. */
if ((sqp->s_flags & (QIB_S_BUSY | QIB_S_ANY_WAIT)) ||
!(ib_qib_state_ops[sqp->state] & QIB_PROCESS_OR_FLUSH_SEND))
goto unlock;
sqp->s_flags |= QIB_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_qib_state_ops[sqp->state] & QIB_PROCESS_NEXT_SEND_OK)) {
if (!(ib_qib_state_ops[sqp->state] & QIB_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_qib_state_ops[qp->state] & QIB_PROCESS_RECV_OK) ||
qp->ibqp.qp_type != sqp->ibqp.qp_type) {
ibp->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;
release = 1;
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;
/* FALLTHROUGH */
case IB_WR_SEND:
ret = qib_get_rwqe(qp, 0);
if (ret < 0)
goto op_err;
if (!ret)
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;
ret = qib_get_rwqe(qp, 1);
if (ret < 0)
goto op_err;
if (!ret)
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(!qib_rkey_ok(qp, &qp->r_sge.sge, wqe->length,
wqe->wr.wr.rdma.remote_addr,
wqe->wr.wr.rdma.rkey,
IB_ACCESS_REMOTE_WRITE)))
goto acc_err;
qp->r_sge.sg_list = NULL;
qp->r_sge.num_sge = 1;
qp->r_sge.total_len = wqe->length;
break;
case IB_WR_RDMA_READ:
if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_READ)))
goto inv_err;
if (unlikely(!qib_rkey_ok(qp, &sqp->s_sge.sge, wqe->length,
wqe->wr.wr.rdma.remote_addr,
wqe->wr.wr.rdma.rkey,
IB_ACCESS_REMOTE_READ)))
goto acc_err;
release = 0;
sqp->s_sge.sg_list = NULL;
sqp->s_sge.num_sge = 1;
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;
qp->r_sge.total_len = wqe->length;
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(!qib_rkey_ok(qp, &qp->r_sge.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);
qib_put_mr(qp->r_sge.sge.mr);
qp->r_sge.num_sge = 0;
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);
qib_copy_sge(&qp->r_sge, sge->vaddr, len, release);
sge->vaddr += len;
sge->length -= len;
sge->sge_length -= len;
if (sge->sge_length == 0) {
if (!release)
qib_put_mr(sge->mr);
if (--sqp->s_sge.num_sge)
*sge = *sqp->s_sge.sg_list++;
} else if (sge->length == 0 && sge->mr->lkey) {
if (++sge->n >= QIB_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 (release)
qib_put_ss(&qp->r_sge);
if (!test_and_clear_bit(QIB_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. */
qib_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);
ibp->n_loop_pkts++;
flush_send:
sqp->s_rnr_retry = sqp->s_rnr_retry_cnt;
qib_send_complete(sqp, wqe, send_status);
goto again;
rnr_nak:
/* Handle RNR NAK */
if (qp->ibqp.qp_type == IB_QPT_UC)
goto send_comp;
ibp->n_rnr_naks++;
/*
* 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_qib_state_ops[sqp->state] & QIB_PROCESS_RECV_OK))
goto clr_busy;
sqp->s_flags |= QIB_S_WAIT_RNR;
sqp->s_timer.function = qib_rc_rnr_retry;
sqp->s_timer.expires = jiffies +
usecs_to_jiffies(ib_qib_rnr_table[qp->r_min_rnr_timer]);
add_timer(&sqp->s_timer);
goto clr_busy;
op_err:
send_status = IB_WC_REM_OP_ERR;
wc.status = IB_WC_LOC_QP_OP_ERR;
goto err;
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 */
qib_rc_error(qp, wc.status);
serr:
spin_lock_irqsave(&sqp->s_lock, flags);
qib_send_complete(sqp, wqe, send_status);
if (sqp->ibqp.qp_type == IB_QPT_RC) {
int lastwqe = qib_error_qp(sqp, IB_WC_WR_FLUSH_ERR);
sqp->s_flags &= ~QIB_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 &= ~QIB_S_BUSY;
unlock:
spin_unlock_irqrestore(&sqp->s_lock, flags);
done:
if (qp && atomic_dec_and_test(&qp->refcount))
wake_up(&qp->wait);
}
/**
* qib_make_grh - construct a GRH header
* @ibp: a pointer to the IB port
* @hdr: a pointer to the GRH header being constructed
* @grh: the global route address to send to
* @hwords: the number of 32 bit words of header being sent
* @nwords: the number of 32 bit words of data being sent
*
* Return the size of the header in 32 bit words.
*/
u32 qib_make_grh(struct qib_ibport *ibp, struct ib_grh *hdr,
struct ib_global_route *grh, u32 hwords, u32 nwords)
{
hdr->version_tclass_flow =
cpu_to_be32((IB_GRH_VERSION << IB_GRH_VERSION_SHIFT) |
(grh->traffic_class << IB_GRH_TCLASS_SHIFT) |
(grh->flow_label << IB_GRH_FLOW_SHIFT));
hdr->paylen = cpu_to_be16((hwords - 2 + nwords + SIZE_OF_CRC) << 2);
/* next_hdr is defined by C8-7 in ch. 8.4.1 */
hdr->next_hdr = IB_GRH_NEXT_HDR;
hdr->hop_limit = grh->hop_limit;
/* The SGID is 32-bit aligned. */
hdr->sgid.global.subnet_prefix = ibp->gid_prefix;
hdr->sgid.global.interface_id = grh->sgid_index ?
ibp->guids[grh->sgid_index - 1] : ppd_from_ibp(ibp)->guid;
hdr->dgid = grh->dgid;
/* GRH header size in 32-bit words. */
return sizeof(struct ib_grh) / sizeof(u32);
}
void qib_make_ruc_header(struct qib_qp *qp, struct qib_other_headers *ohdr,
u32 bth0, u32 bth2)
{
struct qib_ibport *ibp = to_iport(qp->ibqp.device, qp->port_num);
u16 lrh0;
u32 nwords;
u32 extra_bytes;
/* Construct the header. */
extra_bytes = -qp->s_cur_size & 3;
nwords = (qp->s_cur_size + extra_bytes) >> 2;
lrh0 = QIB_LRH_BTH;
if (unlikely(qp->remote_ah_attr.ah_flags & IB_AH_GRH)) {
qp->s_hdrwords += qib_make_grh(ibp, &qp->s_hdr->u.l.grh,
&qp->remote_ah_attr.grh,
qp->s_hdrwords, nwords);
lrh0 = QIB_LRH_GRH;
}
lrh0 |= ibp->sl_to_vl[qp->remote_ah_attr.sl] << 12 |
qp->remote_ah_attr.sl << 4;
qp->s_hdr->lrh[0] = cpu_to_be16(lrh0);
qp->s_hdr->lrh[1] = cpu_to_be16(qp->remote_ah_attr.dlid);
qp->s_hdr->lrh[2] = cpu_to_be16(qp->s_hdrwords + nwords + SIZE_OF_CRC);
qp->s_hdr->lrh[3] = cpu_to_be16(ppd_from_ibp(ibp)->lid |
qp->remote_ah_attr.src_path_bits);
bth0 |= qib_get_pkey(ibp, qp->s_pkey_index);
bth0 |= extra_bytes << 20;
if (qp->s_mig_state == IB_MIG_MIGRATED)
bth0 |= IB_BTH_MIG_REQ;
ohdr->bth[0] = cpu_to_be32(bth0);
ohdr->bth[1] = cpu_to_be32(qp->remote_qpn);
ohdr->bth[2] = cpu_to_be32(bth2);
}
/**
* qib_do_send - perform a send on a QP
* @work: contains a pointer to the QP
*
* Process entries in the send work queue until credit or queue is
* exhausted. Only allow one CPU to send a packet per QP (tasklet).
* Otherwise, two threads could send packets out of order.
*/
void qib_do_send(struct work_struct *work)
{
struct qib_qp *qp = container_of(work, struct qib_qp, s_work);
struct qib_ibport *ibp = to_iport(qp->ibqp.device, qp->port_num);
struct qib_pportdata *ppd = ppd_from_ibp(ibp);
int (*make_req)(struct qib_qp *qp);
unsigned long flags;
if ((qp->ibqp.qp_type == IB_QPT_RC ||
qp->ibqp.qp_type == IB_QPT_UC) &&
(qp->remote_ah_attr.dlid & ~((1 << ppd->lmc) - 1)) == ppd->lid) {
qib_ruc_loopback(qp);
return;
}
if (qp->ibqp.qp_type == IB_QPT_RC)
make_req = qib_make_rc_req;
else if (qp->ibqp.qp_type == IB_QPT_UC)
make_req = qib_make_uc_req;
else
make_req = qib_make_ud_req;
spin_lock_irqsave(&qp->s_lock, flags);
/* Return if we are already busy processing a work request. */
if (!qib_send_ok(qp)) {
spin_unlock_irqrestore(&qp->s_lock, flags);
return;
}
qp->s_flags |= QIB_S_BUSY;
spin_unlock_irqrestore(&qp->s_lock, flags);
do {
/* Check for a constructed packet to be sent. */
if (qp->s_hdrwords != 0) {
/*
* If the packet cannot be sent now, return and
* the send tasklet will be woken up later.
*/
if (qib_verbs_send(qp, qp->s_hdr, qp->s_hdrwords,
qp->s_cur_sge, qp->s_cur_size))
break;
/* Record that s_hdr is empty. */
qp->s_hdrwords = 0;
}
} while (make_req(qp));
}
/*
* This should be called with s_lock held.
*/
void qib_send_complete(struct qib_qp *qp, struct qib_swqe *wqe,
enum ib_wc_status status)
{
u32 old_last, last;
unsigned i;
if (!(ib_qib_state_ops[qp->state] & QIB_PROCESS_OR_FLUSH_SEND))
return;
for (i = 0; i < wqe->wr.num_sge; i++) {
struct qib_sge *sge = &wqe->sg_list[i];
qib_put_mr(sge->mr);
}
if (qp->ibqp.qp_type == IB_QPT_UD ||
qp->ibqp.qp_type == IB_QPT_SMI ||
qp->ibqp.qp_type == IB_QPT_GSI)
atomic_dec(&to_iah(wqe->wr.wr.ud.ah)->refcount);
/* See ch. 11.2.4.1 and 10.7.3.1 */
if (!(qp->s_flags & QIB_S_SIGNAL_REQ_WR) ||
(wqe->wr.send_flags & IB_SEND_SIGNALED) ||
status != IB_WC_SUCCESS) {
struct ib_wc wc;
memset(&wc, 0, sizeof wc);
wc.wr_id = wqe->wr.wr_id;
wc.status = status;
wc.opcode = ib_qib_wc_opcode[wqe->wr.opcode];
wc.qp = &qp->ibqp;
if (status == IB_WC_SUCCESS)
wc.byte_len = wqe->length;
qib_cq_enter(to_icq(qp->ibqp.send_cq), &wc,
status != IB_WC_SUCCESS);
}
last = qp->s_last;
old_last = last;
if (++last >= qp->s_size)
last = 0;
qp->s_last = last;
if (qp->s_acked == old_last)
qp->s_acked = last;
if (qp->s_cur == old_last)
qp->s_cur = last;
if (qp->s_tail == old_last)
qp->s_tail = last;
if (qp->state == IB_QPS_SQD && last == qp->s_cur)
qp->s_draining = 0;
}
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