/*
* Copyright (c) 2006 QLogic, Inc. 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 "ipath_verbs.h"
#include "ipath_common.h"
/*
* Convert the AETH RNR timeout code into the number of milliseconds.
*/
const u32 ib_ipath_rnr_table[32] = {
656, /* 0 */
1, /* 1 */
1, /* 2 */
1, /* 3 */
1, /* 4 */
1, /* 5 */
1, /* 6 */
1, /* 7 */
1, /* 8 */
1, /* 9 */
1, /* A */
1, /* B */
1, /* C */
1, /* D */
2, /* E */
2, /* F */
3, /* 10 */
4, /* 11 */
6, /* 12 */
8, /* 13 */
11, /* 14 */
16, /* 15 */
21, /* 16 */
31, /* 17 */
41, /* 18 */
62, /* 19 */
82, /* 1A */
123, /* 1B */
164, /* 1C */
246, /* 1D */
328, /* 1E */
492 /* 1F */
};
/**
* ipath_insert_rnr_queue - put QP on the RNR timeout list for the device
* @qp: the QP
*
* XXX Use a simple list for now. We might need a priority
* queue if we have lots of QPs waiting for RNR timeouts
* but that should be rare.
*/
void ipath_insert_rnr_queue(struct ipath_qp *qp)
{
struct ipath_ibdev *dev = to_idev(qp->ibqp.device);
unsigned long flags;
spin_lock_irqsave(&dev->pending_lock, flags);
if (list_empty(&dev->rnrwait))
list_add(&qp->timerwait, &dev->rnrwait);
else {
struct list_head *l = &dev->rnrwait;
struct ipath_qp *nqp = list_entry(l->next, struct ipath_qp,
timerwait);
while (qp->s_rnr_timeout >= nqp->s_rnr_timeout) {
qp->s_rnr_timeout -= nqp->s_rnr_timeout;
l = l->next;
if (l->next == &dev->rnrwait)
break;
nqp = list_entry(l->next, struct ipath_qp,
timerwait);
}
list_add(&qp->timerwait, l);
}
spin_unlock_irqrestore(&dev->pending_lock, flags);
}
/**
* ipath_get_rwqe - copy the next RWQE into the QP's RWQE
* @qp: the QP
* @wr_id_only: update wr_id only, not SGEs
*
* Return 0 if no RWQE is available, otherwise return 1.
*
* Can be called from interrupt level.
*/
int ipath_get_rwqe(struct ipath_qp *qp, int wr_id_only)
{
unsigned long flags;
struct ipath_rq *rq;
struct ipath_srq *srq;
struct ipath_rwqe *wqe;
int ret = 1;
if (!qp->ibqp.srq) {
rq = &qp->r_rq;
spin_lock_irqsave(&rq->lock, flags);
if (unlikely(rq->tail == rq->head)) {
ret = 0;
goto done;
}
wqe = get_rwqe_ptr(rq, rq->tail);
qp->r_wr_id = wqe->wr_id;
if (!wr_id_only) {
qp->r_sge.sge = wqe->sg_list[0];
qp->r_sge.sg_list = wqe->sg_list + 1;
qp->r_sge.num_sge = wqe->num_sge;
qp->r_len = wqe->length;
}
if (++rq->tail >= rq->size)
rq->tail = 0;
goto done;
}
srq = to_isrq(qp->ibqp.srq);
rq = &srq->rq;
spin_lock_irqsave(&rq->lock, flags);
if (unlikely(rq->tail == rq->head)) {
ret = 0;
goto done;
}
wqe = get_rwqe_ptr(rq, rq->tail);
qp->r_wr_id = wqe->wr_id;
if (!wr_id_only) {
qp->r_sge.sge = wqe->sg_list[0];
qp->r_sge.sg_list = wqe->sg_list + 1;
qp->r_sge.num_sge = wqe->num_sge;
qp->r_len = wqe->length;
}
if (++rq->tail >= rq->size)
rq->tail = 0;
if (srq->ibsrq.event_handler) {
struct ib_event ev;
u32 n;
if (rq->head < rq->tail)
n = rq->size + rq->head - rq->tail;
else
n = rq->head - rq->tail;
if (n < srq->limit) {
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;
srq->ibsrq.event_handler(&ev,
srq->ibsrq.srq_context);
goto bail;
}
}
done:
spin_unlock_irqrestore(&rq->lock, flags);
bail:
return ret;
}
/**
* ipath_ruc_loopback - handle UC and RC lookback requests
* @sqp: the loopback QP
*
* This is called from ipath_do_uc_send() or ipath_do_rc_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;
qp = ipath_lookup_qpn(&dev->qp_table, sqp->remote_qpn);
if (!qp) {
dev->n_pkt_drops++;
return;
}
again:
spin_lock_irqsave(&sqp->s_lock, flags);
if (!(ib_ipath_state_ops[sqp->state] & IPATH_PROCESS_SEND_OK)) {
spin_unlock_irqrestore(&sqp->s_lock, flags);
goto done;
}
/* Get the next send request. */
if (sqp->s_last == sqp->s_head) {
/* Send work queue is empty. */
spin_unlock_irqrestore(&sqp->s_lock, flags);
goto done;
}
/*
* We can rely on the entry not changing without the s_lock
* being held until we update s_last.
*/
wqe = get_swqe_ptr(sqp, sqp->s_last);
spin_unlock_irqrestore(&sqp->s_lock, flags);
wc.wc_flags = 0;
wc.imm_data = 0;
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.imm_data;
/* FALLTHROUGH */
case IB_WR_SEND:
if (!ipath_get_rwqe(qp, 0)) {
rnr_nak:
/* Handle RNR NAK */
if (qp->ibqp.qp_type == IB_QPT_UC)
goto send_comp;
if (sqp->s_rnr_retry == 0) {
wc.status = IB_WC_RNR_RETRY_EXC_ERR;
goto err;
}
if (sqp->s_rnr_retry_cnt < 7)
sqp->s_rnr_retry--;
dev->n_rnr_naks++;
sqp->s_rnr_timeout =
ib_ipath_rnr_table[sqp->r_min_rnr_timer];
ipath_insert_rnr_queue(sqp);
goto done;
}
break;
case IB_WR_RDMA_WRITE_WITH_IMM:
wc.wc_flags = IB_WC_WITH_IMM;
wc.imm_data = wqe->wr.imm_data;
if (!ipath_get_rwqe(qp, 1))
goto rnr_nak;
/* FALLTHROUGH */
case IB_WR_RDMA_WRITE:
if (wqe->length == 0)
break;
if (unlikely(!ipath_rkey_ok(dev, &qp->r_sge, wqe->length,
wqe->wr.wr.rdma.remote_addr,
wqe->wr.wr.rdma.rkey,
IB_ACCESS_REMOTE_WRITE))) {
acc_err:
wc.status = IB_WC_REM_ACCESS_ERR;
err:
wc.wr_id = wqe->wr.wr_id;
wc.opcode = ib_ipath_wc_opcode[wqe->wr.opcode];
wc.vendor_err = 0;
wc.byte_len = 0;
wc.qp_num = sqp->ibqp.qp_num;
wc.src_qp = sqp->remote_qpn;
wc.pkey_index = 0;
wc.slid = sqp->remote_ah_attr.dlid;
wc.sl = sqp->remote_ah_attr.sl;
wc.dlid_path_bits = 0;
wc.port_num = 0;
ipath_sqerror_qp(sqp, &wc);
goto done;
}
break;
case IB_WR_RDMA_READ:
if (unlikely(!ipath_rkey_ok(dev, &sqp->s_sge, wqe->length,
wqe->wr.wr.rdma.remote_addr,
wqe->wr.wr.rdma.rkey,
IB_ACCESS_REMOTE_READ)))
goto acc_err;
if (unlikely(!(qp->qp_access_flags &
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(!ipath_rkey_ok(dev, &qp->r_sge, sizeof(u64),
wqe->wr.wr.rdma.remote_addr,
wqe->wr.wr.rdma.rkey,
IB_ACCESS_REMOTE_ATOMIC)))
goto acc_err;
/* Perform atomic OP and save result. */
sdata = wqe->wr.wr.atomic.swap;
spin_lock_irqsave(&dev->pending_lock, flags);
qp->r_atomic_data = *(u64 *) qp->r_sge.sge.vaddr;
if (wqe->wr.opcode == IB_WR_ATOMIC_FETCH_AND_ADD)
*(u64 *) qp->r_sge.sge.vaddr =
qp->r_atomic_data + sdata;
else if (qp->r_atomic_data == wqe->wr.wr.atomic.compare_add)
*(u64 *) qp->r_sge.sge.vaddr = sdata;
spin_unlock_irqrestore(&dev->pending_lock, flags);
*(u64 *) sqp->s_sge.sge.vaddr = qp->r_atomic_data;
goto send_comp;
default:
goto done;
}
sge = &sqp->s_sge.sge;
while (sqp->s_len) {
u32 len = sqp->s_len;
if (len > sge->length)
len = 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 (wqe->wr.opcode == IB_WR_RDMA_WRITE ||
wqe->wr.opcode == IB_WR_RDMA_READ)
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.vendor_err = 0;
wc.byte_len = wqe->length;
wc.qp_num = qp->ibqp.qp_num;
wc.src_qp = qp->remote_qpn;
/* XXX do we know which pkey matched? Only needed for GSI. */
wc.pkey_index = 0;
wc.slid = qp->remote_ah_attr.dlid;
wc.sl = qp->remote_ah_attr.sl;
wc.dlid_path_bits = 0;
/* 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:
sqp->s_rnr_retry = sqp->s_rnr_retry_cnt;
if (!test_bit(IPATH_S_SIGNAL_REQ_WR, &sqp->s_flags) ||
(wqe->wr.send_flags & IB_SEND_SIGNALED)) {
wc.wr_id = wqe->wr.wr_id;
wc.status = IB_WC_SUCCESS;
wc.opcode = ib_ipath_wc_opcode[wqe->wr.opcode];
wc.vendor_err = 0;
wc.byte_len = wqe->length;
wc.qp_num = sqp->ibqp.qp_num;
wc.src_qp = 0;
wc.pkey_index = 0;
wc.slid = 0;
wc.sl = 0;
wc.dlid_path_bits = 0;
wc.port_num = 0;
ipath_cq_enter(to_icq(sqp->ibqp.send_cq), &wc, 0);
}
/* Update s_last now that we are finished with the SWQE */
spin_lock_irqsave(&sqp->s_lock, flags);
if (++sqp->s_last >= sqp->s_size)
sqp->s_last = 0;
spin_unlock_irqrestore(&sqp->s_lock, flags);
goto again;
done:
if (atomic_dec_and_test(&qp->refcount))
wake_up(&qp->wait);
}
/**
* ipath_no_bufs_available - tell the layer driver we need buffers
* @qp: the QP that caused the problem
* @dev: the device we ran out of buffers on
*
* Called when we run out of PIO buffers.
*/
void ipath_no_bufs_available(struct ipath_qp *qp, struct ipath_ibdev *dev)
{
unsigned long flags;
spin_lock_irqsave(&dev->pending_lock, flags);
if (list_empty(&qp->piowait))
list_add_tail(&qp->piowait, &dev->piowait);
spin_unlock_irqrestore(&dev->pending_lock, flags);
/*
* Note that as soon as ipath_layer_want_buffer() is called and
* possibly before it returns, ipath_ib_piobufavail()
* could be called. If we are still in the tasklet function,
* tasklet_hi_schedule() will not call us until the next time
* tasklet_hi_schedule() is called.
* We clear the tasklet flag now since we are committing to return
* from the tasklet function.
*/
clear_bit(IPATH_S_BUSY, &qp->s_flags);
tasklet_unlock(&qp->s_task);
ipath_layer_want_buffer(dev->dd);
dev->n_piowait++;
}
/**
* ipath_post_ruc_send - post RC and UC sends
* @qp: the QP to post on
* @wr: the work request to send
*/
int ipath_post_ruc_send(struct ipath_qp *qp, struct ib_send_wr *wr)
{
struct ipath_swqe *wqe;
unsigned long flags;
u32 next;
int i, j;
int acc;
int ret;
/*
* Don't allow RDMA reads or atomic operations on UC or
* undefined operations.
* Make sure buffer is large enough to hold the result for atomics.
*/
if (qp->ibqp.qp_type == IB_QPT_UC) {
if ((unsigned) wr->opcode >= IB_WR_RDMA_READ) {
ret = -EINVAL;
goto bail;
}
} else if ((unsigned) wr->opcode > IB_WR_ATOMIC_FETCH_AND_ADD) {
ret = -EINVAL;
goto bail;
} else if (wr->opcode >= IB_WR_ATOMIC_CMP_AND_SWP &&
(wr->num_sge == 0 ||
wr->sg_list[0].length < sizeof(u64) ||
wr->sg_list[0].addr & (sizeof(u64) - 1))) {
ret = -EINVAL;
goto bail;
}
/* IB spec says that num_sge == 0 is OK. */
if (wr->num_sge > qp->s_max_sge) {
ret = -ENOMEM;
goto bail;
}
spin_lock_irqsave(&qp->s_lock, flags);
next = qp->s_head + 1;
if (next >= qp->s_size)
next = 0;
if (next == qp->s_last) {
spin_unlock_irqrestore(&qp->s_lock, flags);
ret = -EINVAL;
goto bail;
}
wqe = get_swqe_ptr(qp, qp->s_head);
wqe->wr = *wr;
wqe->ssn = qp->s_ssn++;
wqe->sg_list[0].mr = NULL;
wqe->sg_list[0].vaddr = NULL;
wqe->sg_list[0].length = 0;
wqe->sg_list[0].sge_length = 0;
wqe->length = 0;
acc = wr->opcode >= IB_WR_RDMA_READ ? IB_ACCESS_LOCAL_WRITE : 0;
for (i = 0, j = 0; i < wr->num_sge; i++) {
if (to_ipd(qp->ibqp.pd)->user && wr->sg_list[i].lkey == 0) {
spin_unlock_irqrestore(&qp->s_lock, flags);
ret = -EINVAL;
goto bail;
}
if (wr->sg_list[i].length == 0)
continue;
if (!ipath_lkey_ok(&to_idev(qp->ibqp.device)->lk_table,
&wqe->sg_list[j], &wr->sg_list[i],
acc)) {
spin_unlock_irqrestore(&qp->s_lock, flags);
ret = -EINVAL;
goto bail;
}
wqe->length += wr->sg_list[i].length;
j++;
}
wqe->wr.num_sge = j;
qp->s_head = next;
spin_unlock_irqrestore(&qp->s_lock, flags);
ipath_do_ruc_send((unsigned long) qp);
ret = 0;
bail:
return ret;
}
/**
* ipath_make_grh - construct a GRH header
* @dev: a pointer to the ipath device
* @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 ipath_make_grh(struct ipath_ibdev *dev, struct ib_grh *hdr,
struct ib_global_route *grh, u32 hwords, u32 nwords)
{
hdr->version_tclass_flow =
cpu_to_be32((6 << 28) |
(grh->traffic_class << 20) |
grh->flow_label);
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 = 0x1B;
hdr->hop_limit = grh->hop_limit;
/* The SGID is 32-bit aligned. */
hdr->sgid.global.subnet_prefix = dev->gid_prefix;
hdr->sgid.global.interface_id = ipath_layer_get_guid(dev->dd);
hdr->dgid = grh->dgid;
/* GRH header size in 32-bit words. */
return sizeof(struct ib_grh) / sizeof(u32);
}
/**
* ipath_do_ruc_send - perform a send on an RC or UC QP
* @data: 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, after we drop the QP s_lock, two threads could send
* packets out of order.
*/
void ipath_do_ruc_send(unsigned long data)
{
struct ipath_qp *qp = (struct ipath_qp *)data;
struct ipath_ibdev *dev = to_idev(qp->ibqp.device);
unsigned long flags;
u16 lrh0;
u32 nwords;
u32 extra_bytes;
u32 bth0;
u32 bth2;
u32 pmtu = ib_mtu_enum_to_int(qp->path_mtu);
struct ipath_other_headers *ohdr;
if (test_and_set_bit(IPATH_S_BUSY, &qp->s_flags))
goto bail;
if (unlikely(qp->remote_ah_attr.dlid ==
ipath_layer_get_lid(dev->dd))) {
ipath_ruc_loopback(qp);
goto clear;
}
ohdr = &qp->s_hdr.u.oth;
if (qp->remote_ah_attr.ah_flags & IB_AH_GRH)
ohdr = &qp->s_hdr.u.l.oth;
again:
/* Check for a constructed packet to be sent. */
if (qp->s_hdrwords != 0) {
/*
* If no PIO bufs are available, return. An interrupt will
* call ipath_ib_piobufavail() when one is available.
*/
if (ipath_verbs_send(dev->dd, qp->s_hdrwords,
(u32 *) &qp->s_hdr, qp->s_cur_size,
qp->s_cur_sge)) {
ipath_no_bufs_available(qp, dev);
goto bail;
}
dev->n_unicast_xmit++;
/* Record that we sent the packet and s_hdr is empty. */
qp->s_hdrwords = 0;
}
/*
* The lock is needed to synchronize between setting
* qp->s_ack_state, resend timer, and post_send().
*/
spin_lock_irqsave(&qp->s_lock, flags);
/* Sending responses has higher priority over sending requests. */
if (qp->s_ack_state != IB_OPCODE_RC_ACKNOWLEDGE &&
(bth0 = ipath_make_rc_ack(qp, ohdr, pmtu)) != 0)
bth2 = qp->s_ack_psn++ & IPATH_PSN_MASK;
else if (!((qp->ibqp.qp_type == IB_QPT_RC) ?
ipath_make_rc_req(qp, ohdr, pmtu, &bth0, &bth2) :
ipath_make_uc_req(qp, ohdr, pmtu, &bth0, &bth2))) {
/*
* Clear the busy bit before unlocking to avoid races with
* adding new work queue items and then failing to process
* them.
*/
clear_bit(IPATH_S_BUSY, &qp->s_flags);
spin_unlock_irqrestore(&qp->s_lock, flags);
goto bail;
}
spin_unlock_irqrestore(&qp->s_lock, flags);
/* Construct the header. */
extra_bytes = (4 - qp->s_cur_size) & 3;
nwords = (qp->s_cur_size + extra_bytes) >> 2;
lrh0 = IPATH_LRH_BTH;
if (unlikely(qp->remote_ah_attr.ah_flags & IB_AH_GRH)) {
qp->s_hdrwords += ipath_make_grh(dev, &qp->s_hdr.u.l.grh,
&qp->remote_ah_attr.grh,
qp->s_hdrwords, nwords);
lrh0 = IPATH_LRH_GRH;
}
lrh0 |= 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(ipath_layer_get_lid(dev->dd));
bth0 |= ipath_layer_get_pkey(dev->dd, qp->s_pkey_index);
bth0 |= extra_bytes << 20;
ohdr->bth[0] = cpu_to_be32(bth0);
ohdr->bth[1] = cpu_to_be32(qp->remote_qpn);
ohdr->bth[2] = cpu_to_be32(bth2);
/* Check for more work to do. */
goto again;
clear:
clear_bit(IPATH_S_BUSY, &qp->s_flags);
bail:
return;
}