bnxt_en: Fix max_mtu setting for multi-buf XDP

The existing code does not allow the MTU to be set to the maximum even
after an XDP program supporting multiple buffers is attached.  Fix it
to set the netdev->max_mtu to the maximum value if the attached XDP
program supports mutiple buffers, regardless of the current MTU value.

Also use a local variable dev instead of repeatedly using bp->dev.

Fixes: 1dc4c557bfed ("bnxt: adding bnxt_xdp_build_skb to build skb from multibuffer xdp_buff")
Reviewed-by: Somnath Kotur <somnath.kotur@broadcom.com>
Reviewed-by: Ajit Khaparde <ajit.khaparde@broadcom.com>
Reviewed-by: Andy Gospodarek <andrew.gospodarek@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Link: https://lore.kernel.org/r/20230731142043.58855-3-michael.chan@broadcom.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index 4d36de6915a09034cf3a6863a8224f2a28e0836d..1eb490c48c52e974a669e712706bb1fd5904a6c4 100644 (file)
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -4001,26 +4001,29 @@ void bnxt_set_ring_params(struct bnxt *bp)
  */
 int bnxt_set_rx_skb_mode(struct bnxt *bp, bool page_mode)
 {
+       struct net_device *dev = bp->dev;
+
        if (page_mode) {
                bp->flags &= ~BNXT_FLAG_AGG_RINGS;
                bp->flags |= BNXT_FLAG_RX_PAGE_MODE;
 
-               if (bp->dev->mtu > BNXT_MAX_PAGE_MODE_MTU) {
+               if (bp->xdp_prog->aux->xdp_has_frags)
+                       dev->max_mtu = min_t(u16, bp->max_mtu, BNXT_MAX_MTU);
+               else
+                       dev->max_mtu =
+                               min_t(u16, bp->max_mtu, BNXT_MAX_PAGE_MODE_MTU);
+               if (dev->mtu > BNXT_MAX_PAGE_MODE_MTU) {
                        bp->flags |= BNXT_FLAG_JUMBO;
                        bp->rx_skb_func = bnxt_rx_multi_page_skb;
-                       bp->dev->max_mtu =
-                               min_t(u16, bp->max_mtu, BNXT_MAX_MTU);
                } else {
                        bp->flags |= BNXT_FLAG_NO_AGG_RINGS;
                        bp->rx_skb_func = bnxt_rx_page_skb;
-                       bp->dev->max_mtu =
-                               min_t(u16, bp->max_mtu, BNXT_MAX_PAGE_MODE_MTU);
                }
                bp->rx_dir = DMA_BIDIRECTIONAL;
                /* Disable LRO or GRO_HW */
-               netdev_update_features(bp->dev);
+               netdev_update_features(dev);
        } else {
-               bp->dev->max_mtu = bp->max_mtu;
+               dev->max_mtu = bp->max_mtu;
                bp->flags &= ~BNXT_FLAG_RX_PAGE_MODE;
                bp->rx_dir = DMA_FROM_DEVICE;
                bp->rx_skb_func = bnxt_rx_skb;