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path: root/drivers/net/usb/cdc_ncm.c
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Diffstat (limited to 'drivers/net/usb/cdc_ncm.c')
-rw-r--r--drivers/net/usb/cdc_ncm.c61
1 files changed, 55 insertions, 6 deletions
diff --git a/drivers/net/usb/cdc_ncm.c b/drivers/net/usb/cdc_ncm.c
index 8067b8fbb0ee..1991e4a24657 100644
--- a/drivers/net/usb/cdc_ncm.c
+++ b/drivers/net/usb/cdc_ncm.c
@@ -684,10 +684,12 @@ static void cdc_ncm_free(struct cdc_ncm_ctx *ctx)
ctx->tx_curr_skb = NULL;
}
+ kfree(ctx->delayed_ndp16);
+
kfree(ctx);
}
-int cdc_ncm_bind_common(struct usbnet *dev, struct usb_interface *intf, u8 data_altsetting)
+int cdc_ncm_bind_common(struct usbnet *dev, struct usb_interface *intf, u8 data_altsetting, int drvflags)
{
const struct usb_cdc_union_desc *union_desc = NULL;
struct cdc_ncm_ctx *ctx;
@@ -855,6 +857,17 @@ advance:
/* finish setting up the device specific data */
cdc_ncm_setup(dev);
+ /* Device-specific flags */
+ ctx->drvflags = drvflags;
+
+ /* Allocate the delayed NDP if needed. */
+ if (ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END) {
+ ctx->delayed_ndp16 = kzalloc(ctx->max_ndp_size, GFP_KERNEL);
+ if (!ctx->delayed_ndp16)
+ goto error2;
+ dev_info(&intf->dev, "NDP will be placed at end of frame for this device.");
+ }
+
/* override ethtool_ops */
dev->net->ethtool_ops = &cdc_ncm_ethtool_ops;
@@ -954,8 +967,11 @@ static int cdc_ncm_bind(struct usbnet *dev, struct usb_interface *intf)
if (cdc_ncm_select_altsetting(intf) != CDC_NCM_COMM_ALTSETTING_NCM)
return -ENODEV;
- /* The NCM data altsetting is fixed */
- ret = cdc_ncm_bind_common(dev, intf, CDC_NCM_DATA_ALTSETTING_NCM);
+ /* The NCM data altsetting is fixed, so we hard-coded it.
+ * Additionally, generic NCM devices are assumed to accept arbitrarily
+ * placed NDP.
+ */
+ ret = cdc_ncm_bind_common(dev, intf, CDC_NCM_DATA_ALTSETTING_NCM, 0);
/*
* We should get an event when network connection is "connected" or
@@ -986,6 +1002,14 @@ static struct usb_cdc_ncm_ndp16 *cdc_ncm_ndp(struct cdc_ncm_ctx *ctx, struct sk_
struct usb_cdc_ncm_nth16 *nth16 = (void *)skb->data;
size_t ndpoffset = le16_to_cpu(nth16->wNdpIndex);
+ /* If NDP should be moved to the end of the NCM package, we can't follow the
+ * NTH16 header as we would normally do. NDP isn't written to the SKB yet, and
+ * the wNdpIndex field in the header is actually not consistent with reality. It will be later.
+ */
+ if (ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END)
+ if (ctx->delayed_ndp16->dwSignature == sign)
+ return ctx->delayed_ndp16;
+
/* follow the chain of NDPs, looking for a match */
while (ndpoffset) {
ndp16 = (struct usb_cdc_ncm_ndp16 *)(skb->data + ndpoffset);
@@ -995,7 +1019,8 @@ static struct usb_cdc_ncm_ndp16 *cdc_ncm_ndp(struct cdc_ncm_ctx *ctx, struct sk_
}
/* align new NDP */
- cdc_ncm_align_tail(skb, ctx->tx_ndp_modulus, 0, ctx->tx_max);
+ if (!(ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END))
+ cdc_ncm_align_tail(skb, ctx->tx_ndp_modulus, 0, ctx->tx_max);
/* verify that there is room for the NDP and the datagram (reserve) */
if ((ctx->tx_max - skb->len - reserve) < ctx->max_ndp_size)
@@ -1008,7 +1033,11 @@ static struct usb_cdc_ncm_ndp16 *cdc_ncm_ndp(struct cdc_ncm_ctx *ctx, struct sk_
nth16->wNdpIndex = cpu_to_le16(skb->len);
/* push a new empty NDP */
- ndp16 = (struct usb_cdc_ncm_ndp16 *)memset(skb_put(skb, ctx->max_ndp_size), 0, ctx->max_ndp_size);
+ if (!(ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END))
+ ndp16 = (struct usb_cdc_ncm_ndp16 *)memset(skb_put(skb, ctx->max_ndp_size), 0, ctx->max_ndp_size);
+ else
+ ndp16 = ctx->delayed_ndp16;
+
ndp16->dwSignature = sign;
ndp16->wLength = cpu_to_le16(sizeof(struct usb_cdc_ncm_ndp16) + sizeof(struct usb_cdc_ncm_dpe16));
return ndp16;
@@ -1023,6 +1052,15 @@ cdc_ncm_fill_tx_frame(struct usbnet *dev, struct sk_buff *skb, __le32 sign)
struct sk_buff *skb_out;
u16 n = 0, index, ndplen;
u8 ready2send = 0;
+ u32 delayed_ndp_size;
+
+ /* When our NDP gets written in cdc_ncm_ndp(), then skb_out->len gets updated
+ * accordingly. Otherwise, we should check here.
+ */
+ if (ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END)
+ delayed_ndp_size = ctx->max_ndp_size;
+ else
+ delayed_ndp_size = 0;
/* if there is a remaining skb, it gets priority */
if (skb != NULL) {
@@ -1077,7 +1115,7 @@ cdc_ncm_fill_tx_frame(struct usbnet *dev, struct sk_buff *skb, __le32 sign)
cdc_ncm_align_tail(skb_out, ctx->tx_modulus, ctx->tx_remainder, ctx->tx_max);
/* check if we had enough room left for both NDP and frame */
- if (!ndp16 || skb_out->len + skb->len > ctx->tx_max) {
+ if (!ndp16 || skb_out->len + skb->len + delayed_ndp_size > ctx->tx_max) {
if (n == 0) {
/* won't fit, MTU problem? */
dev_kfree_skb_any(skb);
@@ -1150,6 +1188,17 @@ cdc_ncm_fill_tx_frame(struct usbnet *dev, struct sk_buff *skb, __le32 sign)
/* variables will be reset at next call */
}
+ /* If requested, put NDP at end of frame. */
+ if (ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END) {
+ nth16 = (struct usb_cdc_ncm_nth16 *)skb_out->data;
+ cdc_ncm_align_tail(skb_out, ctx->tx_ndp_modulus, 0, ctx->tx_max);
+ nth16->wNdpIndex = cpu_to_le16(skb_out->len);
+ memcpy(skb_put(skb_out, ctx->max_ndp_size), ctx->delayed_ndp16, ctx->max_ndp_size);
+
+ /* Zero out delayed NDP - signature checking will naturally fail. */
+ ndp16 = memset(ctx->delayed_ndp16, 0, ctx->max_ndp_size);
+ }
+
/* If collected data size is less or equal ctx->min_tx_pkt
* bytes, we send buffers as it is. If we get more data, it
* would be more efficient for USB HS mobile device with DMA