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IB/ipath: misc infiniband code, part 2 

Management datagram support, queue pairs, and reliable and unreliable
connections.

Signed-off-by: Bryan O'Sullivan <bos@pathscale.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
This commit is contained in:
Bryan O'Sullivan 2006-03-29 15:23:37 -08:00 committed by Roland Dreier
parent cef1cce5c8
commit e28c00ad67
3 changed files with 2817 additions and 0 deletions
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1352
drivers/infiniband/hw/ipath/ipath_mad.c Normal file
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drivers/infiniband/hw/ipath/ipath_qp.c Normal file
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/*
* 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/err.h>
#include <linux/vmalloc.h>
#include "ipath_verbs.h"
#include "ips_common.h"
#define BITS_PER_PAGE (PAGE_SIZE*BITS_PER_BYTE)
#define BITS_PER_PAGE_MASK (BITS_PER_PAGE-1)
#define mk_qpn(qpt, map, off) (((map) - (qpt)->map) * BITS_PER_PAGE + \
(off))
#define find_next_offset(map, off) find_next_zero_bit((map)->page, \
BITS_PER_PAGE, off)
#define TRANS_INVALID 0
#define TRANS_ANY2RST 1
#define TRANS_RST2INIT 2
#define TRANS_INIT2INIT 3
#define TRANS_INIT2RTR 4
#define TRANS_RTR2RTS 5
#define TRANS_RTS2RTS 6
#define TRANS_SQERR2RTS 7
#define TRANS_ANY2ERR 8
#define TRANS_RTS2SQD 9 /* XXX Wait for expected ACKs & signal event */
#define TRANS_SQD2SQD 10 /* error if not drained & parameter change */
#define TRANS_SQD2RTS 11 /* error if not drained */
/*
* Convert the AETH credit code into the number of credits.
*/
static u32 credit_table[31] = {
0, /* 0 */
1, /* 1 */
2, /* 2 */
3, /* 3 */
4, /* 4 */
6, /* 5 */
8, /* 6 */
12, /* 7 */
16, /* 8 */
24, /* 9 */
32, /* A */
48, /* B */
64, /* C */
96, /* D */
128, /* E */
192, /* F */
256, /* 10 */
384, /* 11 */
512, /* 12 */
768, /* 13 */
1024, /* 14 */
1536, /* 15 */
2048, /* 16 */
3072, /* 17 */
4096, /* 18 */
6144, /* 19 */
8192, /* 1A */
12288, /* 1B */
16384, /* 1C */
24576, /* 1D */
32768 /* 1E */
};
static u32 alloc_qpn(struct ipath_qp_table *qpt)
{
u32 i, offset, max_scan, qpn;
struct qpn_map *map;
u32 ret;
qpn = qpt->last + 1;
if (qpn >= QPN_MAX)
qpn = 2;
offset = qpn & BITS_PER_PAGE_MASK;
map = &qpt->map[qpn / BITS_PER_PAGE];
max_scan = qpt->nmaps - !offset;
for (i = 0;;) {
if (unlikely(!map->page)) {
unsigned long page = get_zeroed_page(GFP_KERNEL);
unsigned long flags;
/*
* Free the page if someone raced with us
* installing it:
*/
spin_lock_irqsave(&qpt->lock, flags);
if (map->page)
free_page(page);
else
map->page = (void *)page;
spin_unlock_irqrestore(&qpt->lock, flags);
if (unlikely(!map->page))
break;
}
if (likely(atomic_read(&map->n_free))) {
do {
if (!test_and_set_bit(offset, map->page)) {
atomic_dec(&map->n_free);
qpt->last = qpn;
ret = qpn;
goto bail;
}
offset = find_next_offset(map, offset);
qpn = mk_qpn(qpt, map, offset);
/*
* This test differs from alloc_pidmap().
* If find_next_offset() does find a zero
* bit, we don't need to check for QPN
* wrapping around past our starting QPN.
* We just need to be sure we don't loop
* forever.
*/
} while (offset < BITS_PER_PAGE && qpn < QPN_MAX);
}
/*
* In order to keep the number of pages allocated to a
* minimum, we scan the all existing pages before increasing
* the size of the bitmap table.
*/
if (++i > max_scan) {
if (qpt->nmaps == QPNMAP_ENTRIES)
break;
map = &qpt->map[qpt->nmaps++];
offset = 0;
} else if (map < &qpt->map[qpt->nmaps]) {
++map;
offset = 0;
} else {
map = &qpt->map[0];
offset = 2;
}
qpn = mk_qpn(qpt, map, offset);
}
ret = 0;
bail:
return ret;
}
static void free_qpn(struct ipath_qp_table *qpt, u32 qpn)
{
struct qpn_map *map;
map = qpt->map + qpn / BITS_PER_PAGE;
if (map->page)
clear_bit(qpn & BITS_PER_PAGE_MASK, map->page);
atomic_inc(&map->n_free);
}
/**
* ipath_alloc_qpn - allocate a QP number
* @qpt: the QP table
* @qp: the QP
* @type: the QP type (IB_QPT_SMI and IB_QPT_GSI are special)
*
* Allocate the next available QPN and put the QP into the hash table.
* The hash table holds a reference to the QP.
*/
int ipath_alloc_qpn(struct ipath_qp_table *qpt, struct ipath_qp *qp,
enum ib_qp_type type)
{
unsigned long flags;
u32 qpn;
int ret;
if (type == IB_QPT_SMI)
qpn = 0;
else if (type == IB_QPT_GSI)
qpn = 1;
else {
/* Allocate the next available QPN */
qpn = alloc_qpn(qpt);
if (qpn == 0) {
ret = -ENOMEM;
goto bail;
}
}
qp->ibqp.qp_num = qpn;
/* Add the QP to the hash table. */
spin_lock_irqsave(&qpt->lock, flags);
qpn %= qpt->max;
qp->next = qpt->table[qpn];
qpt->table[qpn] = qp;
atomic_inc(&qp->refcount);
spin_unlock_irqrestore(&qpt->lock, flags);
ret = 0;
bail:
return ret;
}
/**
* ipath_free_qp - remove a QP from the QP table
* @qpt: the QP table
* @qp: the QP to remove
*
* Remove the QP from the table so it can't be found asynchronously by
* the receive interrupt routine.
*/
void ipath_free_qp(struct ipath_qp_table *qpt, struct ipath_qp *qp)
{
struct ipath_qp *q, **qpp;
unsigned long flags;
int fnd = 0;
spin_lock_irqsave(&qpt->lock, flags);
/* Remove QP from the hash table. */
qpp = &qpt->table[qp->ibqp.qp_num % qpt->max];
for (; (q = *qpp) != NULL; qpp = &q->next) {
if (q == qp) {
*qpp = qp->next;
qp->next = NULL;
atomic_dec(&qp->refcount);
fnd = 1;
break;
}
}
spin_unlock_irqrestore(&qpt->lock, flags);
if (!fnd)
return;
/* If QPN is not reserved, mark QPN free in the bitmap. */
if (qp->ibqp.qp_num > 1)
free_qpn(qpt, qp->ibqp.qp_num);
wait_event(qp->wait, !atomic_read(&qp->refcount));
}
/**
* ipath_free_all_qps - remove all QPs from the table
* @qpt: the QP table to empty
*/
void ipath_free_all_qps(struct ipath_qp_table *qpt)
{
unsigned long flags;
struct ipath_qp *qp, *nqp;
u32 n;
for (n = 0; n < qpt->max; n++) {
spin_lock_irqsave(&qpt->lock, flags);
qp = qpt->table[n];
qpt->table[n] = NULL;
spin_unlock_irqrestore(&qpt->lock, flags);
while (qp) {
nqp = qp->next;
if (qp->ibqp.qp_num > 1)
free_qpn(qpt, qp->ibqp.qp_num);
if (!atomic_dec_and_test(&qp->refcount) ||
!ipath_destroy_qp(&qp->ibqp))
_VERBS_INFO("QP memory leak!\n");
qp = nqp;
}
}
for (n = 0; n < ARRAY_SIZE(qpt->map); n++) {
if (qpt->map[n].page)
free_page((unsigned long)qpt->map[n].page);
}
}
/**
* ipath_lookup_qpn - return the QP with the given QPN
* @qpt: the QP table
* @qpn: the QP number to look up
*
* The caller is responsible for decrementing the QP reference count
* when done.
*/
struct ipath_qp *ipath_lookup_qpn(struct ipath_qp_table *qpt, u32 qpn)
{
unsigned long flags;
struct ipath_qp *qp;
spin_lock_irqsave(&qpt->lock, flags);
for (qp = qpt->table[qpn % qpt->max]; qp; qp = qp->next) {
if (qp->ibqp.qp_num == qpn) {
atomic_inc(&qp->refcount);
break;
}
}
spin_unlock_irqrestore(&qpt->lock, flags);
return qp;
}
/**
* ipath_reset_qp - initialize the QP state to the reset state
* @qp: the QP to reset
*/
static void ipath_reset_qp(struct ipath_qp *qp)
{
qp->remote_qpn = 0;
qp->qkey = 0;
qp->qp_access_flags = 0;
qp->s_hdrwords = 0;
qp->s_psn = 0;
qp->r_psn = 0;
atomic_set(&qp->msn, 0);
if (qp->ibqp.qp_type == IB_QPT_RC) {
qp->s_state = IB_OPCODE_RC_SEND_LAST;
qp->r_state = IB_OPCODE_RC_SEND_LAST;
} else {
qp->s_state = IB_OPCODE_UC_SEND_LAST;
qp->r_state = IB_OPCODE_UC_SEND_LAST;
}
qp->s_ack_state = IB_OPCODE_RC_ACKNOWLEDGE;
qp->s_nak_state = 0;
qp->s_rnr_timeout = 0;
qp->s_head = 0;
qp->s_tail = 0;
qp->s_cur = 0;
qp->s_last = 0;
qp->s_ssn = 1;
qp->s_lsn = 0;
qp->r_rq.head = 0;
qp->r_rq.tail = 0;
qp->r_reuse_sge = 0;
}
/**
* ipath_modify_qp - modify the attributes of a queue pair
* @ibqp: the queue pair who's attributes we're modifying
* @attr: the new attributes
* @attr_mask: the mask of attributes to modify
*
* Returns 0 on success, otherwise returns an errno.
*/
int ipath_modify_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr,
int attr_mask)
{
struct ipath_qp *qp = to_iqp(ibqp);
enum ib_qp_state cur_state, new_state;
unsigned long flags;
int ret;
spin_lock_irqsave(&qp->r_rq.lock, flags);
spin_lock(&qp->s_lock);
cur_state = attr_mask & IB_QP_CUR_STATE ?
attr->cur_qp_state : qp->state;
new_state = attr_mask & IB_QP_STATE ? attr->qp_state : cur_state;
if (!ib_modify_qp_is_ok(cur_state, new_state, ibqp->qp_type,
attr_mask))
goto inval;
switch (new_state) {
case IB_QPS_RESET:
ipath_reset_qp(qp);
break;
case IB_QPS_ERR:
ipath_error_qp(qp);
break;
default:
break;
}
if (attr_mask & IB_QP_PKEY_INDEX) {
struct ipath_ibdev *dev = to_idev(ibqp->device);
if (attr->pkey_index >= ipath_layer_get_npkeys(dev->dd))
goto inval;
qp->s_pkey_index = attr->pkey_index;
}
if (attr_mask & IB_QP_DEST_QPN)
qp->remote_qpn = attr->dest_qp_num;
if (attr_mask & IB_QP_SQ_PSN) {
qp->s_next_psn = attr->sq_psn;
qp->s_last_psn = qp->s_next_psn - 1;
}
if (attr_mask & IB_QP_RQ_PSN)
qp->r_psn = attr->rq_psn;
if (attr_mask & IB_QP_ACCESS_FLAGS)
qp->qp_access_flags = attr->qp_access_flags;
if (attr_mask & IB_QP_AV) {
if (attr->ah_attr.dlid == 0 ||
attr->ah_attr.dlid >= IPS_MULTICAST_LID_BASE)
goto inval;
qp->remote_ah_attr = attr->ah_attr;
}
if (attr_mask & IB_QP_PATH_MTU)
qp->path_mtu = attr->path_mtu;
if (attr_mask & IB_QP_RETRY_CNT)
qp->s_retry = qp->s_retry_cnt = attr->retry_cnt;
if (attr_mask & IB_QP_RNR_RETRY) {
qp->s_rnr_retry = attr->rnr_retry;
if (qp->s_rnr_retry > 7)
qp->s_rnr_retry = 7;
qp->s_rnr_retry_cnt = qp->s_rnr_retry;
}
if (attr_mask & IB_QP_MIN_RNR_TIMER) {
if (attr->min_rnr_timer > 31)
goto inval;
qp->s_min_rnr_timer = attr->min_rnr_timer;
}
if (attr_mask & IB_QP_QKEY)
qp->qkey = attr->qkey;
if (attr_mask & IB_QP_PKEY_INDEX)
qp->s_pkey_index = attr->pkey_index;
qp->state = new_state;
spin_unlock(&qp->s_lock);
spin_unlock_irqrestore(&qp->r_rq.lock, flags);
/*
* If QP1 changed to the RTS state, try to move to the link to INIT
* even if it was ACTIVE so the SM will reinitialize the SMA's
* state.
*/
if (qp->ibqp.qp_num == 1 && new_state == IB_QPS_RTS) {
struct ipath_ibdev *dev = to_idev(ibqp->device);
ipath_layer_set_linkstate(dev->dd, IPATH_IB_LINKDOWN);
}
ret = 0;
goto bail;
inval:
spin_unlock(&qp->s_lock);
spin_unlock_irqrestore(&qp->r_rq.lock, flags);
ret = -EINVAL;
bail:
return ret;
}
int ipath_query_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr,
int attr_mask, struct ib_qp_init_attr *init_attr)
{
struct ipath_qp *qp = to_iqp(ibqp);
attr->qp_state = qp->state;
attr->cur_qp_state = attr->qp_state;
attr->path_mtu = qp->path_mtu;
attr->path_mig_state = 0;
attr->qkey = qp->qkey;
attr->rq_psn = qp->r_psn;
attr->sq_psn = qp->s_next_psn;
attr->dest_qp_num = qp->remote_qpn;
attr->qp_access_flags = qp->qp_access_flags;
attr->cap.max_send_wr = qp->s_size - 1;
attr->cap.max_recv_wr = qp->r_rq.size - 1;
attr->cap.max_send_sge = qp->s_max_sge;
attr->cap.max_recv_sge = qp->r_rq.max_sge;
attr->cap.max_inline_data = 0;
attr->ah_attr = qp->remote_ah_attr;
memset(&attr->alt_ah_attr, 0, sizeof(attr->alt_ah_attr));
attr->pkey_index = qp->s_pkey_index;
attr->alt_pkey_index = 0;
attr->en_sqd_async_notify = 0;
attr->sq_draining = 0;
attr->max_rd_atomic = 1;
attr->max_dest_rd_atomic = 1;
attr->min_rnr_timer = qp->s_min_rnr_timer;
attr->port_num = 1;
attr->timeout = 0;
attr->retry_cnt = qp->s_retry_cnt;
attr->rnr_retry = qp->s_rnr_retry;
attr->alt_port_num = 0;
attr->alt_timeout = 0;
init_attr->event_handler = qp->ibqp.event_handler;
init_attr->qp_context = qp->ibqp.qp_context;
init_attr->send_cq = qp->ibqp.send_cq;
init_attr->recv_cq = qp->ibqp.recv_cq;
init_attr->srq = qp->ibqp.srq;
init_attr->cap = attr->cap;
init_attr->sq_sig_type =
(qp->s_flags & (1 << IPATH_S_SIGNAL_REQ_WR))
? IB_SIGNAL_REQ_WR : 0;
init_attr->qp_type = qp->ibqp.qp_type;
init_attr->port_num = 1;
return 0;
}
/**
* ipath_compute_aeth - compute the AETH (syndrome + MSN)
* @qp: the queue pair to compute the AETH for
*
* Returns the AETH.
*
* The QP s_lock should be held.
*/
__be32 ipath_compute_aeth(struct ipath_qp *qp)
{
u32 aeth = atomic_read(&qp->msn) & IPS_MSN_MASK;
if (qp->s_nak_state) {
aeth |= qp->s_nak_state << IPS_AETH_CREDIT_SHIFT;
} else if (qp->ibqp.srq) {
/*
* Shared receive queues don't generate credits.
* Set the credit field to the invalid value.
*/
aeth |= IPS_AETH_CREDIT_INVAL << IPS_AETH_CREDIT_SHIFT;
} else {
u32 min, max, x;
u32 credits;
/*
* Compute the number of credits available (RWQEs).
* XXX Not holding the r_rq.lock here so there is a small
* chance that the pair of reads are not atomic.
*/
credits = qp->r_rq.head - qp->r_rq.tail;
if ((int)credits < 0)
credits += qp->r_rq.size;
/*
* Binary search the credit table to find the code to
* use.
*/
min = 0;
max = 31;
for (;;) {
x = (min + max) / 2;
if (credit_table[x] == credits)
break;
if (credit_table[x] > credits)
max = x;
else if (min == x)
break;
else
min = x;
}
aeth |= x << IPS_AETH_CREDIT_SHIFT;
}
return cpu_to_be32(aeth);
}
/**
* ipath_create_qp - create a queue pair for a device
* @ibpd: the protection domain who's device we create the queue pair for
* @init_attr: the attributes of the queue pair
* @udata: unused by InfiniPath
*
* Returns the queue pair on success, otherwise returns an errno.
*
* Called by the ib_create_qp() core verbs function.
*/
struct ib_qp *ipath_create_qp(struct ib_pd *ibpd,
struct ib_qp_init_attr *init_attr,
struct ib_udata *udata)
{
struct ipath_qp *qp;
int err;
struct ipath_swqe *swq = NULL;
struct ipath_ibdev *dev;
size_t sz;
struct ib_qp *ret;
if (init_attr->cap.max_send_sge > 255 ||
init_attr->cap.max_recv_sge > 255) {
ret = ERR_PTR(-ENOMEM);
goto bail;
}
switch (init_attr->qp_type) {
case IB_QPT_UC:
case IB_QPT_RC:
sz = sizeof(struct ipath_sge) *
init_attr->cap.max_send_sge +
sizeof(struct ipath_swqe);
swq = vmalloc((init_attr->cap.max_send_wr + 1) * sz);
if (swq == NULL) {
ret = ERR_PTR(-ENOMEM);
goto bail;
}
/* FALLTHROUGH */
case IB_QPT_UD:
case IB_QPT_SMI:
case IB_QPT_GSI:
qp = kmalloc(sizeof(*qp), GFP_KERNEL);
if (!qp) {
ret = ERR_PTR(-ENOMEM);
goto bail;
}
qp->r_rq.size = init_attr->cap.max_recv_wr + 1;
sz = sizeof(struct ipath_sge) *
init_attr->cap.max_recv_sge +
sizeof(struct ipath_rwqe);
qp->r_rq.wq = vmalloc(qp->r_rq.size * sz);
if (!qp->r_rq.wq) {
kfree(qp);
ret = ERR_PTR(-ENOMEM);
goto bail;
}
/*
* ib_create_qp() will initialize qp->ibqp
* except for qp->ibqp.qp_num.
*/
spin_lock_init(&qp->s_lock);
spin_lock_init(&qp->r_rq.lock);
atomic_set(&qp->refcount, 0);
init_waitqueue_head(&qp->wait);
tasklet_init(&qp->s_task,
init_attr->qp_type == IB_QPT_RC ?
ipath_do_rc_send : ipath_do_uc_send,
(unsigned long)qp);
qp->piowait.next = LIST_POISON1;
qp->piowait.prev = LIST_POISON2;
qp->timerwait.next = LIST_POISON1;
qp->timerwait.prev = LIST_POISON2;
qp->state = IB_QPS_RESET;
qp->s_wq = swq;
qp->s_size = init_attr->cap.max_send_wr + 1;
qp->s_max_sge = init_attr->cap.max_send_sge;
qp->r_rq.max_sge = init_attr->cap.max_recv_sge;
qp->s_flags = init_attr->sq_sig_type == IB_SIGNAL_REQ_WR ?
1 << IPATH_S_SIGNAL_REQ_WR : 0;
dev = to_idev(ibpd->device);
err = ipath_alloc_qpn(&dev->qp_table, qp,
init_attr->qp_type);
if (err) {
vfree(swq);
vfree(qp->r_rq.wq);
kfree(qp);
ret = ERR_PTR(err);
goto bail;
}
ipath_reset_qp(qp);
/* Tell the core driver that the kernel SMA is present. */
if (qp->ibqp.qp_type == IB_QPT_SMI)
ipath_layer_set_verbs_flags(dev->dd,
IPATH_VERBS_KERNEL_SMA);
break;
default:
/* Don't support raw QPs */
ret = ERR_PTR(-ENOSYS);
goto bail;
}
init_attr->cap.max_inline_data = 0;
ret = &qp->ibqp;
bail:
return ret;
}
/**
* ipath_destroy_qp - destroy a queue pair
* @ibqp: the queue pair to destroy
*
* Returns 0 on success.
*
* Note that this can be called while the QP is actively sending or
* receiving!
*/
int ipath_destroy_qp(struct ib_qp *ibqp)
{
struct ipath_qp *qp = to_iqp(ibqp);
struct ipath_ibdev *dev = to_idev(ibqp->device);
unsigned long flags;
/* Tell the core driver that the kernel SMA is gone. */
if (qp->ibqp.qp_type == IB_QPT_SMI)
ipath_layer_set_verbs_flags(dev->dd, 0);
spin_lock_irqsave(&qp->r_rq.lock, flags);
spin_lock(&qp->s_lock);
qp->state = IB_QPS_ERR;
spin_unlock(&qp->s_lock);
spin_unlock_irqrestore(&qp->r_rq.lock, flags);
/* Stop the sending tasklet. */
tasklet_kill(&qp->s_task);
/* Make sure the QP isn't on the timeout list. */
spin_lock_irqsave(&dev->pending_lock, flags);
if (qp->timerwait.next != LIST_POISON1)
list_del(&qp->timerwait);
if (qp->piowait.next != LIST_POISON1)
list_del(&qp->piowait);
spin_unlock_irqrestore(&dev->pending_lock, flags);
/*
* Make sure that the QP is not in the QPN table so receive
* interrupts will discard packets for this QP. XXX Also remove QP
* from multicast table.
*/
if (atomic_read(&qp->refcount) != 0)
ipath_free_qp(&dev->qp_table, qp);
vfree(qp->s_wq);
vfree(qp->r_rq.wq);
kfree(qp);
return 0;
}
/**
* ipath_init_qp_table - initialize the QP table for a device
* @idev: the device who's QP table we're initializing
* @size: the size of the QP table
*
* Returns 0 on success, otherwise returns an errno.
*/
int ipath_init_qp_table(struct ipath_ibdev *idev, int size)
{
int i;
int ret;
idev->qp_table.last = 1; /* QPN 0 and 1 are special. */
idev->qp_table.max = size;
idev->qp_table.nmaps = 1;
idev->qp_table.table = kzalloc(size * sizeof(*idev->qp_table.table),
GFP_KERNEL);
if (idev->qp_table.table == NULL) {
ret = -ENOMEM;
goto bail;
}
for (i = 0; i < ARRAY_SIZE(idev->qp_table.map); i++) {
atomic_set(&idev->qp_table.map[i].n_free, BITS_PER_PAGE);
idev->qp_table.map[i].page = NULL;
}
ret = 0;
bail:
return ret;
}
/**
* ipath_sqerror_qp - put a QP's send queue into an error state
* @qp: QP who's send queue will be put into an error state
* @wc: the WC responsible for putting the QP in this state
*
* Flushes the send work queue.
* The QP s_lock should be held.
*/
void ipath_sqerror_qp(struct ipath_qp *qp, struct ib_wc *wc)
{
struct ipath_ibdev *dev = to_idev(qp->ibqp.device);
struct ipath_swqe *wqe = get_swqe_ptr(qp, qp->s_last);
_VERBS_INFO("Send queue error on QP%d/%d: err: %d\n",
qp->ibqp.qp_num, qp->remote_qpn, wc->status);
spin_lock(&dev->pending_lock);
/* XXX What if its already removed by the timeout code? */
if (qp->timerwait.next != LIST_POISON1)
list_del(&qp->timerwait);
if (qp->piowait.next != LIST_POISON1)
list_del(&qp->piowait);
spin_unlock(&dev->pending_lock);
ipath_cq_enter(to_icq(qp->ibqp.send_cq), wc, 1);
if (++qp->s_last >= qp->s_size)
qp->s_last = 0;
wc->status = IB_WC_WR_FLUSH_ERR;
while (qp->s_last != qp->s_head) {
wc->wr_id = wqe->wr.wr_id;
wc->opcode = ib_ipath_wc_opcode[wqe->wr.opcode];
ipath_cq_enter(to_icq(qp->ibqp.send_cq), wc, 1);
if (++qp->s_last >= qp->s_size)
qp->s_last = 0;
wqe = get_swqe_ptr(qp, qp->s_last);
}
qp->s_cur = qp->s_tail = qp->s_head;
qp->state = IB_QPS_SQE;
}
/**
* ipath_error_qp - put a QP into an error state
* @qp: the QP to put into an error state
*
* Flushes both send and receive work queues.
* QP r_rq.lock and s_lock should be held.
*/
void ipath_error_qp(struct ipath_qp *qp)
{
struct ipath_ibdev *dev = to_idev(qp->ibqp.device);
struct ib_wc wc;
_VERBS_INFO("QP%d/%d in error state\n",
qp->ibqp.qp_num, qp->remote_qpn);
spin_lock(&dev->pending_lock);
/* XXX What if its already removed by the timeout code? */
if (qp->timerwait.next != LIST_POISON1)
list_del(&qp->timerwait);
if (qp->piowait.next != LIST_POISON1)
list_del(&qp->piowait);
spin_unlock(&dev->pending_lock);
wc.status = IB_WC_WR_FLUSH_ERR;
wc.vendor_err = 0;
wc.byte_len = 0;
wc.imm_data = 0;
wc.qp_num = qp->ibqp.qp_num;
wc.src_qp = 0;
wc.wc_flags = 0;
wc.pkey_index = 0;
wc.slid = 0;
wc.sl = 0;
wc.dlid_path_bits = 0;
wc.port_num = 0;
while (qp->s_last != qp->s_head) {
struct ipath_swqe *wqe = get_swqe_ptr(qp, qp->s_last);
wc.wr_id = wqe->wr.wr_id;
wc.opcode = ib_ipath_wc_opcode[wqe->wr.opcode];
if (++qp->s_last >= qp->s_size)
qp->s_last = 0;
ipath_cq_enter(to_icq(qp->ibqp.send_cq), &wc, 1);
}
qp->s_cur = qp->s_tail = qp->s_head;
qp->s_hdrwords = 0;
qp->s_ack_state = IB_OPCODE_RC_ACKNOWLEDGE;
wc.opcode = IB_WC_RECV;
while (qp->r_rq.tail != qp->r_rq.head) {
wc.wr_id = get_rwqe_ptr(&qp->r_rq, qp->r_rq.tail)->wr_id;
if (++qp->r_rq.tail >= qp->r_rq.size)
qp->r_rq.tail = 0;
ipath_cq_enter(to_icq(qp->ibqp.recv_cq), &wc, 1);
}
}
/**
* ipath_get_credit - flush the send work queue of a QP
* @qp: the qp who's send work queue to flush
* @aeth: the Acknowledge Extended Transport Header
*
* The QP s_lock should be held.
*/
void ipath_get_credit(struct ipath_qp *qp, u32 aeth)
{
u32 credit = (aeth >> IPS_AETH_CREDIT_SHIFT) & IPS_AETH_CREDIT_MASK;
/*
* If the credit is invalid, we can send
* as many packets as we like. Otherwise, we have to
* honor the credit field.
*/
if (credit == IPS_AETH_CREDIT_INVAL) {
qp->s_lsn = (u32) -1;
} else if (qp->s_lsn != (u32) -1) {
/* Compute new LSN (i.e., MSN + credit) */
credit = (aeth + credit_table[credit]) & IPS_MSN_MASK;
if (ipath_cmp24(credit, qp->s_lsn) > 0)
qp->s_lsn = credit;
}
/* Restart sending if it was blocked due to lack of credits. */
if (qp->s_cur != qp->s_head &&
(qp->s_lsn == (u32) -1 ||
ipath_cmp24(get_swqe_ptr(qp, qp->s_cur)->ssn,
qp->s_lsn + 1) <= 0))
tasklet_hi_schedule(&qp->s_task);
}

552
drivers/infiniband/hw/ipath/ipath_ruc.c Normal file
View File

@ -0,0 +1,552 @@
/*
* 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"
/*
* 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.
*
* Called at interrupt level with the QP r_rq.lock held.
*/
int ipath_get_rwqe(struct ipath_qp *qp, int wr_id_only)
{
struct ipath_rq *rq;
struct ipath_srq *srq;
struct ipath_rwqe *wqe;
int ret;
if (!qp->ibqp.srq) {
rq = &qp->r_rq;
if (unlikely(rq->tail == rq->head)) {
ret = 0;
goto bail;
}
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;
ret = 1;
goto bail;
}
srq = to_isrq(qp->ibqp.srq);
rq = &srq->rq;
spin_lock(&rq->lock);
if (unlikely(rq->tail == rq->head)) {
spin_unlock(&rq->lock);
ret = 0;
goto bail;
}
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(&rq->lock);
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);
} else
spin_unlock(&rq->lock);
} else
spin_unlock(&rq->lock);
ret = 1;
bail:
return ret;
}
/**
* ipath_ruc_loopback - handle UC and RC lookback requests
* @sqp: the loopback QP
* @wc: the work completion entry
*
* 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.
*/
void ipath_ruc_loopback(struct ipath_qp *sqp, struct ib_wc *wc)
{
struct ipath_ibdev *dev = to_idev(sqp->ibqp.device);
struct ipath_qp *qp;
struct ipath_swqe *wqe;
struct ipath_sge *sge;
unsigned long flags;
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:
spin_lock_irqsave(&qp->r_rq.lock, flags);
if (!ipath_get_rwqe(qp, 0)) {
rnr_nak:
spin_unlock_irqrestore(&qp->r_rq.lock, flags);
/* 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->s_min_rnr_timer];
ipath_insert_rnr_queue(sqp);
goto done;
}
spin_unlock_irqrestore(&qp->r_rq.lock, flags);
break;
case IB_WR_RDMA_WRITE_WITH_IMM:
wc->wc_flags = IB_WC_WITH_IMM;
wc->imm_data = wqe->wr.imm_data;
spin_lock_irqsave(&qp->r_rq.lock, flags);
if (!ipath_get_rwqe(qp, 1))
goto rnr_nak;
spin_unlock_irqrestore(&qp->r_rq.lock, flags);
/* 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 (qp->piowait.next == LIST_POISON1)
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_rc_send - post RC and UC sends
* @qp: the QP to post on
* @wr: the work request to send
*/
int ipath_post_rc_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;
/*
* Wake up the send tasklet if the QP is not waiting
* for an RNR timeout.
*/
next = qp->s_rnr_timeout;
spin_unlock_irqrestore(&qp->s_lock, flags);
if (next == 0) {
if (qp->ibqp.qp_type == IB_QPT_UC)
ipath_do_uc_send((unsigned long) qp);
else
ipath_do_rc_send((unsigned long) qp);
}
ret = 0;
bail:
return ret;
}