diff options
| -rw-r--r-- | drivers/net/bnx2.c | 13 |
1 files changed, 10 insertions, 3 deletions
diff --git a/drivers/net/bnx2.c b/drivers/net/bnx2.c index 7d824cf8ee2d..f296c37f29b6 100644 --- a/drivers/net/bnx2.c +++ b/drivers/net/bnx2.c @@ -217,9 +217,16 @@ static inline u32 bnx2_tx_avail(struct bnx2 *bp) u32 diff; smp_mb(); - diff = TX_RING_IDX(bp->tx_prod) - TX_RING_IDX(bp->tx_cons); - if (diff > MAX_TX_DESC_CNT) - diff = (diff & MAX_TX_DESC_CNT) - 1; + + /* The ring uses 256 indices for 255 entries, one of them + * needs to be skipped. + */ + diff = bp->tx_prod - bp->tx_cons; + if (unlikely(diff >= TX_DESC_CNT)) { + diff &= 0xffff; + if (diff == TX_DESC_CNT) + diff = MAX_TX_DESC_CNT; + } return (bp->tx_ring_size - diff); } |