[SRU][J:azure][PATCH 1/1] net: mana: Fix oversized sge0 for GSO packets
Vinicius Peixoto
vinicius.peixoto at canonical.com
Fri Mar 14 21:43:35 UTC 2025
From: Haiyang Zhang <haiyangz at microsoft.com>
BugLink: https://bugs.launchpad.net/bugs/2102678
Handle the case when GSO SKB linear length is too large.
MANA NIC requires GSO packets to put only the header part to SGE0,
otherwise the TX queue may stop at the HW level.
So, use 2 SGEs for the skb linear part which contains more than the
packet header.
Fixes: ca9c54d2d6a5 ("net: mana: Add a driver for Microsoft Azure Network Adapter (MANA)")
Signed-off-by: Haiyang Zhang <haiyangz at microsoft.com>
Reviewed-by: Simon Horman <horms at kernel.org>
Reviewed-by: Shradha Gupta <shradhagupta at linux.microsoft.com>
Signed-off-by: Paolo Abeni <pabeni at redhat.com>
(backported from commit a43e8e9ffa0d1de058964edf1a0622cbb7e27cfe)
[vpeixoto: this had conflicts due to missing commits bd7fc6e1957c2
("net: mana: Add new MANA VF performance counters for easier
troubleshooting") and 504148fedb85 ("net: add skb_[inner_]tcp_all_headers
helpers"); address this by removing the stats update parts and changing
all occurrences of the skb_[inner_]tcp_all_headers helpers to other
equivalent size calculations (from the many examples available in the
diff for commit 504148fedb85)]
Signed-off-by: Vinicius Peixoto <vinicius.peixoto at canonical.com>
---
drivers/net/ethernet/microsoft/mana/mana_en.c | 160 ++++++++++++++----
include/net/mana/mana.h | 5 +-
2 files changed, 128 insertions(+), 37 deletions(-)
diff --git a/drivers/net/ethernet/microsoft/mana/mana_en.c b/drivers/net/ethernet/microsoft/mana/mana_en.c
index 729012a22626..c7c44aedd518 100644
--- a/drivers/net/ethernet/microsoft/mana/mana_en.c
+++ b/drivers/net/ethernet/microsoft/mana/mana_en.c
@@ -89,63 +89,137 @@ static unsigned int mana_checksum_info(struct sk_buff *skb)
return 0;
}
+static void mana_add_sge(struct mana_tx_package *tp, struct mana_skb_head *ash,
+ int sg_i, dma_addr_t da, int sge_len, u32 gpa_mkey)
+{
+ ash->dma_handle[sg_i] = da;
+ ash->size[sg_i] = sge_len;
+
+ tp->wqe_req.sgl[sg_i].address = da;
+ tp->wqe_req.sgl[sg_i].mem_key = gpa_mkey;
+ tp->wqe_req.sgl[sg_i].size = sge_len;
+}
+
static int mana_map_skb(struct sk_buff *skb, struct mana_port_context *apc,
- struct mana_tx_package *tp)
+ struct mana_tx_package *tp, int gso_hs)
{
struct mana_skb_head *ash = (struct mana_skb_head *)skb->head;
+ int hsg = 1; /* num of SGEs of linear part */
struct gdma_dev *gd = apc->ac->gdma_dev;
+ int skb_hlen = skb_headlen(skb);
+ int sge0_len, sge1_len = 0;
struct gdma_context *gc;
struct device *dev;
skb_frag_t *frag;
dma_addr_t da;
+ int sg_i;
int i;
gc = gd->gdma_context;
dev = gc->dev;
- da = dma_map_single(dev, skb->data, skb_headlen(skb), DMA_TO_DEVICE);
+ if (gso_hs && gso_hs < skb_hlen) {
+ sge0_len = gso_hs;
+ sge1_len = skb_hlen - gso_hs;
+ } else {
+ sge0_len = skb_hlen;
+ }
+
+ da = dma_map_single(dev, skb->data, sge0_len, DMA_TO_DEVICE);
if (dma_mapping_error(dev, da))
return -ENOMEM;
- ash->dma_handle[0] = da;
- ash->size[0] = skb_headlen(skb);
+ mana_add_sge(tp, ash, 0, da, sge0_len, gd->gpa_mkey);
- tp->wqe_req.sgl[0].address = ash->dma_handle[0];
- tp->wqe_req.sgl[0].mem_key = gd->gpa_mkey;
- tp->wqe_req.sgl[0].size = ash->size[0];
+ if (sge1_len) {
+ sg_i = 1;
+ da = dma_map_single(dev, skb->data + sge0_len, sge1_len,
+ DMA_TO_DEVICE);
+ if (dma_mapping_error(dev, da))
+ goto frag_err;
+
+ mana_add_sge(tp, ash, sg_i, da, sge1_len, gd->gpa_mkey);
+ hsg = 2;
+ }
for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
+ sg_i = hsg + i;
+
frag = &skb_shinfo(skb)->frags[i];
da = skb_frag_dma_map(dev, frag, 0, skb_frag_size(frag),
DMA_TO_DEVICE);
-
if (dma_mapping_error(dev, da))
goto frag_err;
- ash->dma_handle[i + 1] = da;
- ash->size[i + 1] = skb_frag_size(frag);
-
- tp->wqe_req.sgl[i + 1].address = ash->dma_handle[i + 1];
- tp->wqe_req.sgl[i + 1].mem_key = gd->gpa_mkey;
- tp->wqe_req.sgl[i + 1].size = ash->size[i + 1];
+ mana_add_sge(tp, ash, sg_i, da, skb_frag_size(frag),
+ gd->gpa_mkey);
}
return 0;
frag_err:
- for (i = i - 1; i >= 0; i--)
- dma_unmap_page(dev, ash->dma_handle[i + 1], ash->size[i + 1],
+ for (i = sg_i - 1; i >= hsg; i--)
+ dma_unmap_page(dev, ash->dma_handle[i], ash->size[i],
DMA_TO_DEVICE);
- dma_unmap_single(dev, ash->dma_handle[0], ash->size[0], DMA_TO_DEVICE);
+ for (i = hsg - 1; i >= 0; i--)
+ dma_unmap_single(dev, ash->dma_handle[i], ash->size[i],
+ DMA_TO_DEVICE);
return -ENOMEM;
}
+/* Handle the case when GSO SKB linear length is too large.
+ * MANA NIC requires GSO packets to put only the packet header to SGE0.
+ * So, we need 2 SGEs for the skb linear part which contains more than the
+ * header.
+ * Return a positive value for the number of SGEs, or a negative value
+ * for an error.
+ */
+static int mana_fix_skb_head(struct net_device *ndev, struct sk_buff *skb,
+ int gso_hs)
+{
+ int num_sge = 1 + skb_shinfo(skb)->nr_frags;
+ int skb_hlen = skb_headlen(skb);
+
+ if (gso_hs < skb_hlen) {
+ num_sge++;
+ } else if (gso_hs > skb_hlen) {
+ if (net_ratelimit())
+ netdev_err(ndev,
+ "TX nonlinear head: hs:%d, skb_hlen:%d\n",
+ gso_hs, skb_hlen);
+
+ return -EINVAL;
+ }
+
+ return num_sge;
+}
+
+/* Get the GSO packet's header size */
+static int mana_get_gso_hs(struct sk_buff *skb)
+{
+ int gso_hs;
+
+ if (skb->encapsulation) {
+ gso_hs = skb_inner_transport_offset(skb) + inner_tcp_hdrlen(skb);
+ } else {
+ if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4) {
+ gso_hs = skb_transport_offset(skb) +
+ sizeof(struct udphdr);
+ } else {
+ gso_hs = skb_transport_offset(skb) + tcp_hdrlen(skb);
+ }
+ }
+
+ return gso_hs;
+}
+
netdev_tx_t mana_start_xmit(struct sk_buff *skb, struct net_device *ndev)
{
enum mana_tx_pkt_format pkt_fmt = MANA_SHORT_PKT_FMT;
struct mana_port_context *apc = netdev_priv(ndev);
+ int gso_hs = 0; /* zero for non-GSO pkts */
u16 txq_idx = skb_get_queue_mapping(skb);
struct gdma_dev *gd = apc->ac->gdma_dev;
bool ipv4 = false, ipv6 = false;
@@ -198,19 +272,6 @@ netdev_tx_t mana_start_xmit(struct sk_buff *skb, struct net_device *ndev)
pkg.wqe_req.client_data_unit = 0;
pkg.wqe_req.num_sge = 1 + skb_shinfo(skb)->nr_frags;
- WARN_ON_ONCE(pkg.wqe_req.num_sge > MAX_TX_WQE_SGL_ENTRIES);
-
- if (pkg.wqe_req.num_sge <= ARRAY_SIZE(pkg.sgl_array)) {
- pkg.wqe_req.sgl = pkg.sgl_array;
- } else {
- pkg.sgl_ptr = kmalloc_array(pkg.wqe_req.num_sge,
- sizeof(struct gdma_sge),
- GFP_ATOMIC);
- if (!pkg.sgl_ptr)
- goto tx_drop_count;
-
- pkg.wqe_req.sgl = pkg.sgl_ptr;
- }
if (skb->protocol == htons(ETH_P_IP))
ipv4 = true;
@@ -218,6 +279,16 @@ netdev_tx_t mana_start_xmit(struct sk_buff *skb, struct net_device *ndev)
ipv6 = true;
if (skb_is_gso(skb)) {
+ int num_sge;
+
+ gso_hs = mana_get_gso_hs(skb);
+
+ num_sge = mana_fix_skb_head(ndev, skb, gso_hs);
+ if (num_sge > 0)
+ pkg.wqe_req.num_sge = num_sge;
+ else
+ goto tx_drop_count;
+
pkg.tx_oob.s_oob.is_outer_ipv4 = ipv4;
pkg.tx_oob.s_oob.is_outer_ipv6 = ipv6;
@@ -259,11 +330,25 @@ netdev_tx_t mana_start_xmit(struct sk_buff *skb, struct net_device *ndev)
} else {
/* Can't do offload of this type of checksum */
if (skb_checksum_help(skb))
- goto free_sgl_ptr;
+ goto tx_drop_count;
}
}
- if (mana_map_skb(skb, apc, &pkg))
+ WARN_ON_ONCE(pkg.wqe_req.num_sge > MAX_TX_WQE_SGL_ENTRIES);
+
+ if (pkg.wqe_req.num_sge <= ARRAY_SIZE(pkg.sgl_array)) {
+ pkg.wqe_req.sgl = pkg.sgl_array;
+ } else {
+ pkg.sgl_ptr = kmalloc_array(pkg.wqe_req.num_sge,
+ sizeof(struct gdma_sge),
+ GFP_ATOMIC);
+ if (!pkg.sgl_ptr)
+ goto tx_drop_count;
+
+ pkg.wqe_req.sgl = pkg.sgl_ptr;
+ }
+
+ if (mana_map_skb(skb, apc, &pkg, gso_hs))
goto free_sgl_ptr;
skb_queue_tail(&txq->pending_skbs, skb);
@@ -1218,11 +1303,16 @@ static void mana_unmap_skb(struct sk_buff *skb, struct mana_port_context *apc)
struct mana_skb_head *ash = (struct mana_skb_head *)skb->head;
struct gdma_context *gc = apc->ac->gdma_dev->gdma_context;
struct device *dev = gc->dev;
- int i;
+ int hsg, i;
+
+ /* Number of SGEs of linear part */
+ hsg = (skb_is_gso(skb) && skb_headlen(skb) > ash->size[0]) ? 2 : 1;
- dma_unmap_single(dev, ash->dma_handle[0], ash->size[0], DMA_TO_DEVICE);
+ for (i = 0; i < hsg; i++)
+ dma_unmap_single(dev, ash->dma_handle[i], ash->size[i],
+ DMA_TO_DEVICE);
- for (i = 1; i < skb_shinfo(skb)->nr_frags + 1; i++)
+ for (i = hsg; i < skb_shinfo(skb)->nr_frags + hsg; i++)
dma_unmap_page(dev, ash->dma_handle[i], ash->size[i],
DMA_TO_DEVICE);
}
diff --git a/include/net/mana/mana.h b/include/net/mana/mana.h
index 02a688fcf288..3aaaaafad95a 100644
--- a/include/net/mana/mana.h
+++ b/include/net/mana/mana.h
@@ -91,9 +91,10 @@ struct mana_txq {
/* skb data and frags dma mappings */
struct mana_skb_head {
- dma_addr_t dma_handle[MAX_SKB_FRAGS + 1];
+ /* GSO pkts may have 2 SGEs for the linear part*/
+ dma_addr_t dma_handle[MAX_SKB_FRAGS + 2];
- u32 size[MAX_SKB_FRAGS + 1];
+ u32 size[MAX_SKB_FRAGS + 2];
};
#define MANA_HEADROOM sizeof(struct mana_skb_head)
--
2.45.2
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