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Diffstat (limited to 'drivers/infiniband/sw/rdmavt/qp.c')
-rw-r--r--drivers/infiniband/sw/rdmavt/qp.c677
1 files changed, 660 insertions, 17 deletions
diff --git a/drivers/infiniband/sw/rdmavt/qp.c b/drivers/infiniband/sw/rdmavt/qp.c
index 5ce403c6cddb..1735deb1a9d4 100644
--- a/drivers/infiniband/sw/rdmavt/qp.c
+++ b/drivers/infiniband/sw/rdmavt/qp.c
@@ -118,6 +118,187 @@ const int ib_rvt_state_ops[IB_QPS_ERR + 1] = {
};
EXPORT_SYMBOL(ib_rvt_state_ops);
+/* platform specific: return the last level cache (llc) size, in KiB */
+static int rvt_wss_llc_size(void)
+{
+ /* assume that the boot CPU value is universal for all CPUs */
+ return boot_cpu_data.x86_cache_size;
+}
+
+/* platform specific: cacheless copy */
+static void cacheless_memcpy(void *dst, void *src, size_t n)
+{
+ /*
+ * Use the only available X64 cacheless copy. Add a __user cast
+ * to quiet sparse. The src agument is already in the kernel so
+ * there are no security issues. The extra fault recovery machinery
+ * is not invoked.
+ */
+ __copy_user_nocache(dst, (void __user *)src, n, 0);
+}
+
+void rvt_wss_exit(struct rvt_dev_info *rdi)
+{
+ struct rvt_wss *wss = rdi->wss;
+
+ if (!wss)
+ return;
+
+ /* coded to handle partially initialized and repeat callers */
+ kfree(wss->entries);
+ wss->entries = NULL;
+ kfree(rdi->wss);
+ rdi->wss = NULL;
+}
+
+/**
+ * rvt_wss_init - Init wss data structures
+ *
+ * Return: 0 on success
+ */
+int rvt_wss_init(struct rvt_dev_info *rdi)
+{
+ unsigned int sge_copy_mode = rdi->dparms.sge_copy_mode;
+ unsigned int wss_threshold = rdi->dparms.wss_threshold;
+ unsigned int wss_clean_period = rdi->dparms.wss_clean_period;
+ long llc_size;
+ long llc_bits;
+ long table_size;
+ long table_bits;
+ struct rvt_wss *wss;
+ int node = rdi->dparms.node;
+
+ if (sge_copy_mode != RVT_SGE_COPY_ADAPTIVE) {
+ rdi->wss = NULL;
+ return 0;
+ }
+
+ rdi->wss = kzalloc_node(sizeof(*rdi->wss), GFP_KERNEL, node);
+ if (!rdi->wss)
+ return -ENOMEM;
+ wss = rdi->wss;
+
+ /* check for a valid percent range - default to 80 if none or invalid */
+ if (wss_threshold < 1 || wss_threshold > 100)
+ wss_threshold = 80;
+
+ /* reject a wildly large period */
+ if (wss_clean_period > 1000000)
+ wss_clean_period = 256;
+
+ /* reject a zero period */
+ if (wss_clean_period == 0)
+ wss_clean_period = 1;
+
+ /*
+ * Calculate the table size - the next power of 2 larger than the
+ * LLC size. LLC size is in KiB.
+ */
+ llc_size = rvt_wss_llc_size() * 1024;
+ table_size = roundup_pow_of_two(llc_size);
+
+ /* one bit per page in rounded up table */
+ llc_bits = llc_size / PAGE_SIZE;
+ table_bits = table_size / PAGE_SIZE;
+ wss->pages_mask = table_bits - 1;
+ wss->num_entries = table_bits / BITS_PER_LONG;
+
+ wss->threshold = (llc_bits * wss_threshold) / 100;
+ if (wss->threshold == 0)
+ wss->threshold = 1;
+
+ wss->clean_period = wss_clean_period;
+ atomic_set(&wss->clean_counter, wss_clean_period);
+
+ wss->entries = kcalloc_node(wss->num_entries, sizeof(*wss->entries),
+ GFP_KERNEL, node);
+ if (!wss->entries) {
+ rvt_wss_exit(rdi);
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+/*
+ * Advance the clean counter. When the clean period has expired,
+ * clean an entry.
+ *
+ * This is implemented in atomics to avoid locking. Because multiple
+ * variables are involved, it can be racy which can lead to slightly
+ * inaccurate information. Since this is only a heuristic, this is
+ * OK. Any innaccuracies will clean themselves out as the counter
+ * advances. That said, it is unlikely the entry clean operation will
+ * race - the next possible racer will not start until the next clean
+ * period.
+ *
+ * The clean counter is implemented as a decrement to zero. When zero
+ * is reached an entry is cleaned.
+ */
+static void wss_advance_clean_counter(struct rvt_wss *wss)
+{
+ int entry;
+ int weight;
+ unsigned long bits;
+
+ /* become the cleaner if we decrement the counter to zero */
+ if (atomic_dec_and_test(&wss->clean_counter)) {
+ /*
+ * Set, not add, the clean period. This avoids an issue
+ * where the counter could decrement below the clean period.
+ * Doing a set can result in lost decrements, slowing the
+ * clean advance. Since this a heuristic, this possible
+ * slowdown is OK.
+ *
+ * An alternative is to loop, advancing the counter by a
+ * clean period until the result is > 0. However, this could
+ * lead to several threads keeping another in the clean loop.
+ * This could be mitigated by limiting the number of times
+ * we stay in the loop.
+ */
+ atomic_set(&wss->clean_counter, wss->clean_period);
+
+ /*
+ * Uniquely grab the entry to clean and move to next.
+ * The current entry is always the lower bits of
+ * wss.clean_entry. The table size, wss.num_entries,
+ * is always a power-of-2.
+ */
+ entry = (atomic_inc_return(&wss->clean_entry) - 1)
+ & (wss->num_entries - 1);
+
+ /* clear the entry and count the bits */
+ bits = xchg(&wss->entries[entry], 0);
+ weight = hweight64((u64)bits);
+ /* only adjust the contended total count if needed */
+ if (weight)
+ atomic_sub(weight, &wss->total_count);
+ }
+}
+
+/*
+ * Insert the given address into the working set array.
+ */
+static void wss_insert(struct rvt_wss *wss, void *address)
+{
+ u32 page = ((unsigned long)address >> PAGE_SHIFT) & wss->pages_mask;
+ u32 entry = page / BITS_PER_LONG; /* assumes this ends up a shift */
+ u32 nr = page & (BITS_PER_LONG - 1);
+
+ if (!test_and_set_bit(nr, &wss->entries[entry]))
+ atomic_inc(&wss->total_count);
+
+ wss_advance_clean_counter(wss);
+}
+
+/*
+ * Is the working set larger than the threshold?
+ */
+static inline bool wss_exceeds_threshold(struct rvt_wss *wss)
+{
+ return atomic_read(&wss->total_count) >= wss->threshold;
+}
+
static void get_map_page(struct rvt_qpn_table *qpt,
struct rvt_qpn_map *map)
{
@@ -1164,11 +1345,8 @@ int rvt_modify_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr,
int lastwqe = 0;
int mig = 0;
int pmtu = 0; /* for gcc warning only */
- enum rdma_link_layer link;
int opa_ah;
- link = rdma_port_get_link_layer(ibqp->device, qp->port_num);
-
spin_lock_irq(&qp->r_lock);
spin_lock(&qp->s_hlock);
spin_lock(&qp->s_lock);
@@ -1179,7 +1357,7 @@ int rvt_modify_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr,
opa_ah = rdma_cap_opa_ah(ibqp->device, qp->port_num);
if (!ib_modify_qp_is_ok(cur_state, new_state, ibqp->qp_type,
- attr_mask, link))
+ attr_mask))
goto inval;
if (rdi->driver_f.check_modify_qp &&
@@ -1718,7 +1896,7 @@ static inline int rvt_qp_is_avail(
*/
static int rvt_post_one_wr(struct rvt_qp *qp,
const struct ib_send_wr *wr,
- int *call_send)
+ bool *call_send)
{
struct rvt_swqe *wqe;
u32 next;
@@ -1823,15 +2001,11 @@ static int rvt_post_one_wr(struct rvt_qp *qp,
wqe->wr.num_sge = j;
}
- /* general part of wqe valid - allow for driver checks */
- if (rdi->driver_f.check_send_wqe) {
- ret = rdi->driver_f.check_send_wqe(qp, wqe);
- if (ret < 0)
- goto bail_inval_free;
- if (ret)
- *call_send = ret;
- }
-
+ /*
+ * Calculate and set SWQE PSN values prior to handing it off
+ * to the driver's check routine. This give the driver the
+ * opportunity to adjust PSN values based on internal checks.
+ */
log_pmtu = qp->log_pmtu;
if (qp->ibqp.qp_type != IB_QPT_UC &&
qp->ibqp.qp_type != IB_QPT_RC) {
@@ -1856,8 +2030,18 @@ static int rvt_post_one_wr(struct rvt_qp *qp,
(wqe->length ?
((wqe->length - 1) >> log_pmtu) :
0);
- qp->s_next_psn = wqe->lpsn + 1;
}
+
+ /* general part of wqe valid - allow for driver checks */
+ if (rdi->driver_f.setup_wqe) {
+ ret = rdi->driver_f.setup_wqe(qp, wqe, call_send);
+ if (ret < 0)
+ goto bail_inval_free_ref;
+ }
+
+ if (!(rdi->post_parms[wr->opcode].flags & RVT_OPERATION_LOCAL))
+ qp->s_next_psn = wqe->lpsn + 1;
+
if (unlikely(reserved_op)) {
wqe->wr.send_flags |= RVT_SEND_RESERVE_USED;
rvt_qp_wqe_reserve(qp, wqe);
@@ -1871,6 +2055,10 @@ static int rvt_post_one_wr(struct rvt_qp *qp,
return 0;
+bail_inval_free_ref:
+ if (qp->ibqp.qp_type != IB_QPT_UC &&
+ qp->ibqp.qp_type != IB_QPT_RC)
+ atomic_dec(&ibah_to_rvtah(ud_wr(wr)->ah)->refcount);
bail_inval_free:
/* release mr holds */
while (j) {
@@ -1897,7 +2085,7 @@ int rvt_post_send(struct ib_qp *ibqp, const struct ib_send_wr *wr,
struct rvt_qp *qp = ibqp_to_rvtqp(ibqp);
struct rvt_dev_info *rdi = ib_to_rvt(ibqp->device);
unsigned long flags = 0;
- int call_send;
+ bool call_send;
unsigned nreq = 0;
int err = 0;
@@ -1930,7 +2118,11 @@ int rvt_post_send(struct ib_qp *ibqp, const struct ib_send_wr *wr,
bail:
spin_unlock_irqrestore(&qp->s_hlock, flags);
if (nreq) {
- if (call_send)
+ /*
+ * Only call do_send if there is exactly one packet, and the
+ * driver said it was ok.
+ */
+ if (nreq == 1 && call_send)
rdi->driver_f.do_send(qp);
else
rdi->driver_f.schedule_send_no_lock(qp);
@@ -2465,3 +2657,454 @@ void rvt_qp_iter(struct rvt_dev_info *rdi,
rcu_read_unlock();
}
EXPORT_SYMBOL(rvt_qp_iter);
+
+/*
+ * This should be called with s_lock held.
+ */
+void rvt_send_complete(struct rvt_qp *qp, struct rvt_swqe *wqe,
+ enum ib_wc_status status)
+{
+ u32 old_last, last;
+ struct rvt_dev_info *rdi = ib_to_rvt(qp->ibqp.device);
+
+ if (!(ib_rvt_state_ops[qp->state] & RVT_PROCESS_OR_FLUSH_SEND))
+ return;
+
+ last = qp->s_last;
+ old_last = last;
+ trace_rvt_qp_send_completion(qp, wqe, last);
+ if (++last >= qp->s_size)
+ last = 0;
+ trace_rvt_qp_send_completion(qp, wqe, last);
+ qp->s_last = last;
+ /* See post_send() */
+ barrier();
+ rvt_put_swqe(wqe);
+ if (qp->ibqp.qp_type == IB_QPT_UD ||
+ qp->ibqp.qp_type == IB_QPT_SMI ||
+ qp->ibqp.qp_type == IB_QPT_GSI)
+ atomic_dec(&ibah_to_rvtah(wqe->ud_wr.ah)->refcount);
+
+ rvt_qp_swqe_complete(qp,
+ wqe,
+ rdi->wc_opcode[wqe->wr.opcode],
+ status);
+
+ 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;
+}
+EXPORT_SYMBOL(rvt_send_complete);
+
+/**
+ * rvt_copy_sge - copy data to SGE memory
+ * @qp: associated QP
+ * @ss: the SGE state
+ * @data: the data to copy
+ * @length: the length of the data
+ * @release: boolean to release MR
+ * @copy_last: do a separate copy of the last 8 bytes
+ */
+void rvt_copy_sge(struct rvt_qp *qp, struct rvt_sge_state *ss,
+ void *data, u32 length,
+ bool release, bool copy_last)
+{
+ struct rvt_sge *sge = &ss->sge;
+ int i;
+ bool in_last = false;
+ bool cacheless_copy = false;
+ struct rvt_dev_info *rdi = ib_to_rvt(qp->ibqp.device);
+ struct rvt_wss *wss = rdi->wss;
+ unsigned int sge_copy_mode = rdi->dparms.sge_copy_mode;
+
+ if (sge_copy_mode == RVT_SGE_COPY_CACHELESS) {
+ cacheless_copy = length >= PAGE_SIZE;
+ } else if (sge_copy_mode == RVT_SGE_COPY_ADAPTIVE) {
+ if (length >= PAGE_SIZE) {
+ /*
+ * NOTE: this *assumes*:
+ * o The first vaddr is the dest.
+ * o If multiple pages, then vaddr is sequential.
+ */
+ wss_insert(wss, sge->vaddr);
+ if (length >= (2 * PAGE_SIZE))
+ wss_insert(wss, (sge->vaddr + PAGE_SIZE));
+
+ cacheless_copy = wss_exceeds_threshold(wss);
+ } else {
+ wss_advance_clean_counter(wss);
+ }
+ }
+
+ if (copy_last) {
+ if (length > 8) {
+ length -= 8;
+ } else {
+ copy_last = false;
+ in_last = true;
+ }
+ }
+
+again:
+ while (length) {
+ u32 len = rvt_get_sge_length(sge, length);
+
+ WARN_ON_ONCE(len == 0);
+ if (unlikely(in_last)) {
+ /* enforce byte transfer ordering */
+ for (i = 0; i < len; i++)
+ ((u8 *)sge->vaddr)[i] = ((u8 *)data)[i];
+ } else if (cacheless_copy) {
+ cacheless_memcpy(sge->vaddr, data, len);
+ } else {
+ memcpy(sge->vaddr, data, len);
+ }
+ rvt_update_sge(ss, len, release);
+ data += len;
+ length -= len;
+ }
+
+ if (copy_last) {
+ copy_last = false;
+ in_last = true;
+ length = 8;
+ goto again;
+ }
+}
+EXPORT_SYMBOL(rvt_copy_sge);
+
+/**
+ * ruc_loopback - handle UC and RC loopback requests
+ * @sqp: the sending QP
+ *
+ * This is called from rvt_do_send() to forward a WQE addressed to the same HFI
+ * Note that although we are single threaded due to the send engine, 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 rvt_ruc_loopback(struct rvt_qp *sqp)
+{
+ struct rvt_ibport *rvp = NULL;
+ struct rvt_dev_info *rdi = ib_to_rvt(sqp->ibqp.device);
+ struct rvt_qp *qp;
+ struct rvt_swqe *wqe;
+ struct rvt_sge *sge;
+ unsigned long flags;
+ struct ib_wc wc;
+ u64 sdata;
+ atomic64_t *maddr;
+ enum ib_wc_status send_status;
+ bool release;
+ int ret;
+ bool copy_last = false;
+ int local_ops = 0;
+
+ rcu_read_lock();
+ rvp = rdi->ports[sqp->port_num - 1];
+
+ /*
+ * Note that we check the responder QP state after
+ * checking the requester's state.
+ */
+
+ qp = rvt_lookup_qpn(ib_to_rvt(sqp->ibqp.device), rvp,
+ sqp->remote_qpn);
+
+ spin_lock_irqsave(&sqp->s_lock, flags);
+
+ /* Return if we are already busy processing a work request. */
+ if ((sqp->s_flags & (RVT_S_BUSY | RVT_S_ANY_WAIT)) ||
+ !(ib_rvt_state_ops[sqp->state] & RVT_PROCESS_OR_FLUSH_SEND))
+ goto unlock;
+
+ sqp->s_flags |= RVT_S_BUSY;
+
+again:
+ if (sqp->s_last == READ_ONCE(sqp->s_head))
+ goto clr_busy;
+ wqe = rvt_get_swqe_ptr(sqp, sqp->s_last);
+
+ /* Return if it is not OK to start a new work request. */
+ if (!(ib_rvt_state_ops[sqp->state] & RVT_PROCESS_NEXT_SEND_OK)) {
+ if (!(ib_rvt_state_ops[sqp->state] & RVT_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_rvt_state_ops[qp->state] & RVT_PROCESS_RECV_OK) ||
+ qp->ibqp.qp_type != sqp->ibqp.qp_type) {
+ rvp->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 = true;
+ 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_REG_MR:
+ goto send_comp;
+
+ case IB_WR_LOCAL_INV:
+ if (!(wqe->wr.send_flags & RVT_SEND_COMPLETION_ONLY)) {
+ if (rvt_invalidate_rkey(sqp,
+ wqe->wr.ex.invalidate_rkey))
+ send_status = IB_WC_LOC_PROT_ERR;
+ local_ops = 1;
+ }
+ goto send_comp;
+
+ case IB_WR_SEND_WITH_INV:
+ if (!rvt_invalidate_rkey(qp, wqe->wr.ex.invalidate_rkey)) {
+ wc.wc_flags = IB_WC_WITH_INVALIDATE;
+ wc.ex.invalidate_rkey = wqe->wr.ex.invalidate_rkey;
+ }
+ goto send;
+
+ 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:
+send:
+ ret = rvt_get_rwqe(qp, false);
+ 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 = rvt_get_rwqe(qp, true);
+ if (ret < 0)
+ goto op_err;
+ if (!ret)
+ goto rnr_nak;
+ /* skip copy_last set and qp_access_flags recheck */
+ goto do_write;
+ case IB_WR_RDMA_WRITE:
+ copy_last = rvt_is_user_qp(qp);
+ if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_WRITE)))
+ goto inv_err;
+do_write:
+ if (wqe->length == 0)
+ break;
+ if (unlikely(!rvt_rkey_ok(qp, &qp->r_sge.sge, wqe->length,
+ wqe->rdma_wr.remote_addr,
+ wqe->rdma_wr.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(!rvt_rkey_ok(qp, &sqp->s_sge.sge, wqe->length,
+ wqe->rdma_wr.remote_addr,
+ wqe->rdma_wr.rkey,
+ IB_ACCESS_REMOTE_READ)))
+ goto acc_err;
+ release = false;
+ 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(!rvt_rkey_ok(qp, &qp->r_sge.sge, sizeof(u64),
+ wqe->atomic_wr.remote_addr,
+ wqe->atomic_wr.rkey,
+ IB_ACCESS_REMOTE_ATOMIC)))
+ goto acc_err;
+ /* Perform atomic OP and save result. */
+ maddr = (atomic64_t *)qp->r_sge.sge.vaddr;
+ sdata = wqe->atomic_wr.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->atomic_wr.swap);
+ rvt_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;
+ WARN_ON_ONCE(len == 0);
+ rvt_copy_sge(qp, &qp->r_sge, sge->vaddr,
+ len, release, copy_last);
+ sge->vaddr += len;
+ sge->length -= len;
+ sge->sge_length -= len;
+ if (sge->sge_length == 0) {
+ if (!release)
+ rvt_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 >= RVT_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)
+ rvt_put_ss(&qp->r_sge);
+
+ if (!test_and_clear_bit(RVT_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 = rdma_ah_get_dlid(&qp->remote_ah_attr) & U16_MAX;
+ wc.sl = rdma_ah_get_sl(&qp->remote_ah_attr);
+ wc.port_num = 1;
+ /* Signal completion event if the solicited bit is set. */
+ rvt_cq_enter(ibcq_to_rvtcq(qp->ibqp.recv_cq), &wc,
+ wqe->wr.send_flags & IB_SEND_SOLICITED);
+
+send_comp:
+ spin_lock_irqsave(&sqp->s_lock, flags);
+ rvp->n_loop_pkts++;
+flush_send:
+ sqp->s_rnr_retry = sqp->s_rnr_retry_cnt;
+ rvt_send_complete(sqp, wqe, send_status);
+ if (local_ops) {
+ atomic_dec(&sqp->local_ops_pending);
+ local_ops = 0;
+ }
+ goto again;
+
+rnr_nak:
+ /* Handle RNR NAK */
+ if (qp->ibqp.qp_type == IB_QPT_UC)
+ goto send_comp;
+ rvp->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_rvt_state_ops[sqp->state] & RVT_PROCESS_RECV_OK))
+ goto clr_busy;
+ rvt_add_rnr_timer(sqp, qp->r_min_rnr_timer <<
+ IB_AETH_CREDIT_SHIFT);
+ 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 */
+ rvt_rc_error(qp, wc.status);
+
+serr:
+ spin_lock_irqsave(&sqp->s_lock, flags);
+ rvt_send_complete(sqp, wqe, send_status);
+ if (sqp->ibqp.qp_type == IB_QPT_RC) {
+ int lastwqe = rvt_error_qp(sqp, IB_WC_WR_FLUSH_ERR);
+
+ sqp->s_flags &= ~RVT_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 &= ~RVT_S_BUSY;
+unlock:
+ spin_unlock_irqrestore(&sqp->s_lock, flags);
+done:
+ rcu_read_unlock();
+}
+EXPORT_SYMBOL(rvt_ruc_loopback);