Commit 7c4e983c authored by Alexander Duyck's avatar Alexander Duyck Committed by David S. Miller
Browse files

net: allow gso_max_size to exceed 65536 



The code for gso_max_size was added originally to allow for debugging and
workaround of buggy devices that couldn't support TSO with blocks 64K in
size. The original reason for limiting it to 64K was because that was the
existing limits of IPv4 and non-jumbogram IPv6 length fields.

With the addition of Big TCP we can remove this limit and allow the value
to potentially go up to UINT_MAX and instead be limited by the tso_max_size
value.

So in order to support this we need to go through and clean up the
remaining users of the gso_max_size value so that the values will cap at
64K for non-TCPv6 flows. In addition we can clean up the GSO_MAX_SIZE value
so that 64K becomes GSO_LEGACY_MAX_SIZE and UINT_MAX will now be the upper
limit for GSO_MAX_SIZE.

v6: (edumazet) fixed a compile error if CONFIG_IPV6=n,
               in a new sk_trim_gso_size() helper.
               netif_set_tso_max_size() caps the requested TSO size
               with GSO_MAX_SIZE.

Signed-off-by: default avatarAlexander Duyck <alexanderduyck@fb.com>
Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 89527be8

drivers/net/ethernet/amd/xgbe/xgbe.h

+2 −1
Original line number Diff line number Diff line
@@ -151,7 +151,8 @@ 
#define XGBE_TX_MAX_BUF_SIZE	(0x3fff & ~(64 - 1))



/* Descriptors required for maximum contiguous TSO/GSO packet */

#define XGBE_TX_MAX_SPLIT	((GSO_MAX_SIZE / XGBE_TX_MAX_BUF_SIZE) + 1)

#define XGBE_TX_MAX_SPLIT	\

	((GSO_LEGACY_MAX_SIZE / XGBE_TX_MAX_BUF_SIZE) + 1)



/* Maximum possible descriptors needed for an SKB:

 * - Maximum number of SKB frags

drivers/net/ethernet/mellanox/mlx5/core/en_rx.c

+1 −1
Original line number Diff line number Diff line
@@ -2038,7 +2038,7 @@ mlx5e_hw_gro_skb_has_enough_space(struct sk_buff *skb, u16 data_bcnt) 
{

	int nr_frags = skb_shinfo(skb)->nr_frags;



	return PAGE_SIZE * nr_frags + data_bcnt <= GSO_MAX_SIZE;

	return PAGE_SIZE * nr_frags + data_bcnt <= GRO_MAX_SIZE;

}



static void

drivers/net/ethernet/sfc/ef100_nic.c

+2 −1
Original line number Diff line number Diff line
@@ -1008,7 +1008,8 @@ static int ef100_process_design_param(struct efx_nic *efx, 
		}

		return 0;

	case ESE_EF100_DP_GZ_TSO_MAX_PAYLOAD_LEN:

		nic_data->tso_max_payload_len = min_t(u64, reader->value, GSO_MAX_SIZE);

		nic_data->tso_max_payload_len = min_t(u64, reader->value,

						      GSO_LEGACY_MAX_SIZE);

		netif_set_tso_max_size(efx->net_dev,

				       nic_data->tso_max_payload_len);

		return 0;

drivers/net/ethernet/sfc/falcon/tx.c

+2 −1
Original line number Diff line number Diff line
@@ -98,7 +98,8 @@ unsigned int ef4_tx_max_skb_descs(struct ef4_nic *efx) 
	/* Possibly more for PCIe page boundaries within input fragments */

	if (PAGE_SIZE > EF4_PAGE_SIZE)

		max_descs += max_t(unsigned int, MAX_SKB_FRAGS,

				   DIV_ROUND_UP(GSO_MAX_SIZE, EF4_PAGE_SIZE));

				   DIV_ROUND_UP(GSO_LEGACY_MAX_SIZE,

						EF4_PAGE_SIZE));



	return max_descs;

}

drivers/net/ethernet/sfc/tx_common.c

+2 −1
Original line number Diff line number Diff line
@@ -416,7 +416,8 @@ unsigned int efx_tx_max_skb_descs(struct efx_nic *efx) 
	/* Possibly more for PCIe page boundaries within input fragments */

	if (PAGE_SIZE > EFX_PAGE_SIZE)

		max_descs += max_t(unsigned int, MAX_SKB_FRAGS,

				   DIV_ROUND_UP(GSO_MAX_SIZE, EFX_PAGE_SIZE));

				   DIV_ROUND_UP(GSO_LEGACY_MAX_SIZE,

						EFX_PAGE_SIZE));



	return max_descs;

}