[IB] mthca: fix wraparound handling in mthca_cq_clean()

Handle case where prod_index has wrapped around and become less than
cq->cons_index by checking that their difference as a signed int is
positive rather than comparing directly.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
This commit is contained in:
Roland Dreier 2005-11-09 12:23:17 -08:00
parent 62abb8416f
commit 64044bcf75

View File

@ -258,7 +258,7 @@ void mthca_cq_clean(struct mthca_dev *dev, u32 cqn, u32 qpn,
{
struct mthca_cq *cq;
struct mthca_cqe *cqe;
int prod_index;
u32 prod_index;
int nfreed = 0;
spin_lock_irq(&dev->cq_table.lock);
@ -293,19 +293,15 @@ void mthca_cq_clean(struct mthca_dev *dev, u32 cqn, u32 qpn,
* Now sweep backwards through the CQ, removing CQ entries
* that match our QP by copying older entries on top of them.
*/
while (prod_index > cq->cons_index) {
cqe = get_cqe(cq, (prod_index - 1) & cq->ibcq.cqe);
while ((int) --prod_index - (int) cq->cons_index >= 0) {
cqe = get_cqe(cq, prod_index & cq->ibcq.cqe);
if (cqe->my_qpn == cpu_to_be32(qpn)) {
if (srq)
mthca_free_srq_wqe(srq, be32_to_cpu(cqe->wqe));
++nfreed;
}
else if (nfreed)
memcpy(get_cqe(cq, (prod_index - 1 + nfreed) &
cq->ibcq.cqe),
cqe,
MTHCA_CQ_ENTRY_SIZE);
--prod_index;
} else if (nfreed)
memcpy(get_cqe(cq, (prod_index + nfreed) & cq->ibcq.cqe),
cqe, MTHCA_CQ_ENTRY_SIZE);
}
if (nfreed) {