From f6413a7e32d1f98a258e0ed9abd4df3159902fd3 Mon Sep 17 00:00:00 2001 From: Camelia Groza Date: Mon, 4 Sep 2017 13:57:21 +0300 Subject: [PATCH] sdk_dpaa: ls1043a errata: verify and resize headroom alignment If the skb's headroom isn't aligned to 16 bytes, reallocate the entire skb and resize its headroom to priv->tx_headroom. Update the pointers to the network and transport headers accordingly. Signed-off-by: Camelia Groza --- .../net/ethernet/freescale/sdk_dpaa/dpaa_eth_sg.c | 38 +++++++++++++++------- 1 file changed, 27 insertions(+), 11 deletions(-) --- a/drivers/net/ethernet/freescale/sdk_dpaa/dpaa_eth_sg.c +++ b/drivers/net/ethernet/freescale/sdk_dpaa/dpaa_eth_sg.c @@ -742,14 +742,19 @@ int __hot skb_to_contig_fd(struct dpa_pr EXPORT_SYMBOL(skb_to_contig_fd); #ifndef CONFIG_PPC -/* Verify the conditions that trigger the A010022 errata: 4K memory address - * crossings. +/* Verify the conditions that trigger the A010022 errata: data unaligned to + * 16 bytes and 4K memory address crossings. */ -bool a010022_check_skb(struct sk_buff *skb) +static bool a010022_check_skb(struct sk_buff *skb, struct dpa_priv_s *priv) { int nr_frags, i = 0; skb_frag_t *frag; + /* Check if the headroom is aligned */ + if (((u16)skb->data - priv->tx_headroom) % + priv->buf_layout[TX].data_align != 0) + return true; + /* Check if the headroom crosses a boundary */ if (HAS_DMA_ISSUE(skb->head, skb_headroom(skb))) return true; @@ -767,7 +772,7 @@ bool a010022_check_skb(struct sk_buff *s while (i < nr_frags) { frag = &skb_shinfo(skb)->frags[i]; - /* Check if the paged fragment crosses a boundary from its + /* Check if a paged fragment crosses a boundary from its * offset to its end. */ if (HAS_DMA_ISSUE(frag->page_offset, frag->size)) @@ -783,13 +788,17 @@ bool a010022_check_skb(struct sk_buff *s * page. Build a new skb around the new buffer and release the old one. * A performance drop should be expected. */ -struct sk_buff *a010022_realign_skb(struct sk_buff *skb) +static struct sk_buff *a010022_realign_skb(struct sk_buff *skb, + struct dpa_priv_s *priv) { - int headroom = skb_headroom(skb); + int trans_offset = skb_transport_offset(skb); + int net_offset = skb_network_offset(skb); struct sk_buff *nskb = NULL; + int nsize, headroom; struct page *npage; void *npage_addr; - int nsize; + + headroom = priv->tx_headroom; npage = alloc_page(GFP_ATOMIC); if (unlikely(!npage)) { @@ -822,6 +831,13 @@ struct sk_buff *a010022_realign_skb(stru } copy_skb_header(nskb, skb); + /* We move the headroom when we align it so we have to reset the + * network and transport header offsets relative to the new data + * pointer. The checksum offload relies on these offsets. + */ + skb_set_network_header(nskb, net_offset); + skb_set_transport_header(nskb, trans_offset); + dev_kfree_skb(skb); return nskb; @@ -1024,8 +1040,8 @@ int __hot dpa_tx_extended(struct sk_buff #endif /* CONFIG_FSL_DPAA_TS */ #ifndef CONFIG_PPC - if (unlikely(dpaa_errata_a010022) && a010022_check_skb(skb)) { - skb = a010022_realign_skb(skb); + if (unlikely(dpaa_errata_a010022) && a010022_check_skb(skb, priv)) { + skb = a010022_realign_skb(skb, priv); if (!skb) goto skb_to_fd_failed; } @@ -1072,8 +1088,8 @@ int __hot dpa_tx_extended(struct sk_buff skb = nskb; #ifndef CONFIG_PPC if (unlikely(dpaa_errata_a010022) && - a010022_check_skb(skb)) { - skb = realign_skb(skb); + a010022_check_skb(skb, priv)) { + skb = a010022_realign_skb(skb, priv); if (!skb) goto skb_to_fd_failed; }