bnx2: Call pci_enable_msix() with actual number of vectors.

Based on original patch by Breno Leitão <leitao@linux.vnet.ibm.com>.

Allocate the actual number of vectors and make use of fewer vectors
if pci_enable_msix() returns > 0.  We must allocate one additional
vector for the cnic driver.

Cc: Breno Leitão <leitao@linux.vnet.ibm.com>
Reviewed-by: Benjamin Li <benli@broadcom.com>
Reviewed-by: Matt Carlson <mcarlson@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 20 insertions, 4 deletions

diff --git a/drivers/net/bnx2.c b/drivers/net/bnx2.c
index deb7f83e8245..d44ecc30865f 100644
--- a/drivers/net/bnx2.c
+++ b/drivers/net/bnx2.c
@@ -864,7 +864,7 @@ bnx2_alloc_mem(struct bnx2 *bp)
         bnapi->hw_rx_cons_ptr =
                 &bnapi->status_blk.msi->status_rx_quick_consumer_index0;
         if (bp->flags & BNX2_FLAG_MSIX_CAP) {
-                for (i = 1; i < BNX2_MAX_MSIX_VEC; i++) {
+                for (i = 1; i < bp->irq_nvecs; i++) {
                         struct status_block_msix *sblk;
 
                         bnapi = &bp->bnx2_napi[i];
@@ -6152,7 +6152,7 @@ bnx2_free_irq(struct bnx2 *bp)
 static void
 bnx2_enable_msix(struct bnx2 *bp, int msix_vecs)
 {
-        int i, rc;
+        int i, total_vecs, rc;
         struct msix_entry msix_ent[BNX2_MAX_MSIX_VEC];
         struct net_device *dev = bp->dev;
         const int len = sizeof(bp->irq_tbl[0].name);
@@ -6171,13 +6171,29 @@ bnx2_enable_msix(struct bnx2 *bp, int msix_vecs)
                 msix_ent[i].vector = 0;
         }
 
-        rc = pci_enable_msix(bp->pdev, msix_ent, BNX2_MAX_MSIX_VEC);
+        total_vecs = msix_vecs;
+#ifdef BCM_CNIC
+        total_vecs++;
+#endif
+        rc = -ENOSPC;
+        while (total_vecs >= BNX2_MIN_MSIX_VEC) {
+                rc = pci_enable_msix(bp->pdev, msix_ent, total_vecs);
+                if (rc <= 0)
+                        break;
+                if (rc > 0)
+                        total_vecs = rc;
+        }
+
         if (rc != 0)
                 return;
 
+        msix_vecs = total_vecs;
+#ifdef BCM_CNIC
+        msix_vecs--;
+#endif
         bp->irq_nvecs = msix_vecs;
         bp->flags |= BNX2_FLAG_USING_MSIX | BNX2_FLAG_ONE_SHOT_MSI;
-        for (i = 0; i < BNX2_MAX_MSIX_VEC; i++) {
+        for (i = 0; i < total_vecs; i++) {
                 bp->irq_tbl[i].vector = msix_ent[i].vector;
                 snprintf(bp->irq_tbl[i].name, len, "%s-%d", dev->name, i);
                 bp->irq_tbl[i].handler = bnx2_msi_1shot;