-diff -u a/drivers/net/usb/cdc_mbim.c b/drivers/net/usb/cdc_mbim.c
---- a/drivers/net/usb/cdc_mbim.c 2015-06-28 17:40:40.000000000 +0000
-+++ b/drivers/net/usb/cdc_mbim.c 2015-07-04 15:05:14.546901702 +0000
-@@ -158,7 +158,7 @@
+From 4a0e3e989d66bb7204b163d9cfaa7fa96d0f2023 Mon Sep 17 00:00:00 2001
+From: Enrico Mioso <mrkiko.rs@gmail.com>
+Date: Wed, 8 Jul 2015 13:05:57 +0200
+Subject: [PATCH] cdc_ncm: Add support for moving NDP to end of NCM frame
+
+NCM specs are not actually mandating a specific position in the frame for
+the NDP (Network Datagram Pointer). However, some Huawei devices will
+ignore our aggregates if it is not placed after the datagrams it points
+to. Add support for doing just this, in a per-device configurable way.
+While at it, update NCM subdrivers, disabling this functionality in all of
+them, except in huawei_cdc_ncm where it is enabled instead.
+We aren't making any distinction between different Huawei NCM devices,
+based on what the vendor driver does. Standard NCM devices are left
+unaffected: if they are compliant, they should be always usable, still
+stay on the safe side.
+
+This change has been tested and working with a Huawei E3131 device (which
+works regardless of NDP position), a Huawei E3531 (also working both
+ways) and an E3372 (which mandates NDP to be after indexed datagrams).
+
+V1->V2:
+- corrected wrong NDP acronym definition
+- fixed possible NULL pointer dereference
+- patch cleanup
+V2->V3:
+- Properly account for the NDP size when writing new packets to SKB
+
+Signed-off-by: Enrico Mioso <mrkiko.rs@gmail.com>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ drivers/net/usb/cdc_mbim.c | 2 +-
+ drivers/net/usb/cdc_ncm.c | 61 ++++++++++++++++++++++++++++++++++++----
+ drivers/net/usb/huawei_cdc_ncm.c | 7 +++--
+ include/linux/usb/cdc_ncm.h | 7 ++++-
+ 4 files changed, 67 insertions(+), 10 deletions(-)
+
+--- a/drivers/net/usb/cdc_mbim.c
++++ b/drivers/net/usb/cdc_mbim.c
+@@ -158,7 +158,7 @@ static int cdc_mbim_bind(struct usbnet *
if (!cdc_ncm_comm_intf_is_mbim(intf->cur_altsetting))
goto err;
-
+
- ret = cdc_ncm_bind_common(dev, intf, data_altsetting);
+ ret = cdc_ncm_bind_common(dev, intf, data_altsetting, 0);
if (ret)
goto err;
-
-diff -u a/drivers/net/usb/cdc_ncm.c b/drivers/net/usb/cdc_ncm.c
---- a/drivers/net/usb/cdc_ncm.c 2015-06-28 17:40:40.000000000 +0000
-+++ b/drivers/net/usb/cdc_ncm.c 2015-07-09 08:43:01.658770535 +0000
-@@ -684,10 +684,11 @@
+
+--- 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->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 +856,17 @@
+@@ -855,6 +857,17 @@ advance:
/* finish setting up the device specific data */
cdc_ncm_setup(dev);
-
+
+ /* Device-specific flags */
+ ctx->drvflags = drvflags;
+
+
/* override ethtool_ops */
dev->net->ethtool_ops = &cdc_ncm_ethtool_ops;
-
-@@ -954,8 +966,11 @@
+
+@@ -954,8 +967,11 @@ static int cdc_ncm_bind(struct usbnet *d
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.
+ * 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 +1001,14 @@
+@@ -986,6 +1002,14 @@ static struct usb_cdc_ncm_ndp16 *cdc_ncm
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.
/* follow the chain of NDPs, looking for a match */
while (ndpoffset) {
ndp16 = (struct usb_cdc_ncm_ndp16 *)(skb->data + ndpoffset);
-@@ -995,7 +1018,8 @@
+@@ -995,7 +1019,8 @@ static struct usb_cdc_ncm_ndp16 *cdc_ncm
}
-
+
/* 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 +1032,11 @@
+@@ -1008,7 +1033,11 @@ static struct usb_cdc_ncm_ndp16 *cdc_ncm
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->dwSignature = sign;
ndp16->wLength = cpu_to_le16(sizeof(struct usb_cdc_ncm_ndp16) + sizeof(struct usb_cdc_ncm_dpe16));
return ndp16;
-@@ -1023,6 +1051,15 @@
+@@ -1023,6 +1052,15 @@ cdc_ncm_fill_tx_frame(struct usbnet *dev
struct sk_buff *skb_out;
u16 n = 0, index, ndplen;
u8 ready2send = 0;
+ 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 +1114,7 @@
+@@ -1077,7 +1115,7 @@ cdc_ncm_fill_tx_frame(struct usbnet *dev
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 +1187,17 @@
+@@ -1150,6 +1188,17 @@ cdc_ncm_fill_tx_frame(struct usbnet *dev
/* 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;
/* 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
-diff -u a/drivers/net/usb/huawei_cdc_ncm.c b/drivers/net/usb/huawei_cdc_ncm.c
---- a/drivers/net/usb/huawei_cdc_ncm.c 2015-06-28 17:40:40.000000000 +0000
-+++ b/drivers/net/usb/huawei_cdc_ncm.c 2015-07-04 15:23:25.779014586 +0000
-@@ -73,11 +73,14 @@
+--- a/drivers/net/usb/huawei_cdc_ncm.c
++++ b/drivers/net/usb/huawei_cdc_ncm.c
+@@ -73,11 +73,14 @@ static int huawei_cdc_ncm_bind(struct us
struct usb_driver *subdriver = ERR_PTR(-ENODEV);
int ret = -ENODEV;
struct huawei_cdc_ncm_state *drvstate = (void *)&usbnet_dev->data;
+ int drvflags = 0;
-
+
/* altsetting should always be 1 for NCM devices - so we hard-coded
- * it here
+ * it here. Some huawei devices will need the NDP part of the NCM package to
+ ret = cdc_ncm_bind_common(usbnet_dev, intf, 1, drvflags);
if (ret)
goto err;
-
-diff -u a/include/linux/usb/cdc_ncm.h b/include/linux/usb/cdc_ncm.h
---- a/include/linux/usb/cdc_ncm.h 2015-06-28 17:40:40.000000000 +0000
-+++ b/include/linux/usb/cdc_ncm.h 2015-07-04 15:27:52.171388014 +0000
+
+--- a/include/linux/usb/cdc_ncm.h
++++ b/include/linux/usb/cdc_ncm.h
@@ -80,6 +80,9 @@
#define CDC_NCM_TIMER_INTERVAL_MIN 5UL
#define CDC_NCM_TIMER_INTERVAL_MAX (U32_MAX / NSEC_PER_USEC)
-
+
+/* Driver flags */
-+#define CDC_NCM_FLAG_NDP_TO_END 0x02 /* NDP is placed at end of frame */
++#define CDC_NCM_FLAG_NDP_TO_END 0x02 /* NDP is placed at end of frame */
+
#define cdc_ncm_comm_intf_is_mbim(x) ((x)->desc.bInterfaceSubClass == USB_CDC_SUBCLASS_MBIM && \
(x)->desc.bInterfaceProtocol == USB_CDC_PROTO_NONE)
#define cdc_ncm_data_intf_is_mbim(x) ((x)->desc.bInterfaceProtocol == USB_CDC_MBIM_PROTO_NTB)
-@@ -103,9 +106,11 @@
-
+@@ -103,9 +106,11 @@ struct cdc_ncm_ctx {
+
spinlock_t mtx;
atomic_t stop;
+ int drvflags;
-
+
u32 timer_interval;
u32 max_ndp_size;
+ struct usb_cdc_ncm_ndp16 *delayed_ndp16;
-
+
u32 tx_timer_pending;
u32 tx_curr_frame_num;
-@@ -133,7 +138,7 @@
+@@ -133,7 +138,7 @@ struct cdc_ncm_ctx {
};
-
+
u8 cdc_ncm_select_altsetting(struct usb_interface *intf);
-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);
--- /dev/null
+From 4a0e3e989d66bb7204b163d9cfaa7fa96d0f2023 Mon Sep 17 00:00:00 2001
+From: Enrico Mioso <mrkiko.rs@gmail.com>
+Date: Wed, 8 Jul 2015 13:05:57 +0200
+Subject: [PATCH] cdc_ncm: Add support for moving NDP to end of NCM frame
+
+NCM specs are not actually mandating a specific position in the frame for
+the NDP (Network Datagram Pointer). However, some Huawei devices will
+ignore our aggregates if it is not placed after the datagrams it points
+to. Add support for doing just this, in a per-device configurable way.
+While at it, update NCM subdrivers, disabling this functionality in all of
+them, except in huawei_cdc_ncm where it is enabled instead.
+We aren't making any distinction between different Huawei NCM devices,
+based on what the vendor driver does. Standard NCM devices are left
+unaffected: if they are compliant, they should be always usable, still
+stay on the safe side.
+
+This change has been tested and working with a Huawei E3131 device (which
+works regardless of NDP position), a Huawei E3531 (also working both
+ways) and an E3372 (which mandates NDP to be after indexed datagrams).
+
+V1->V2:
+- corrected wrong NDP acronym definition
+- fixed possible NULL pointer dereference
+- patch cleanup
+V2->V3:
+- Properly account for the NDP size when writing new packets to SKB
+
+Signed-off-by: Enrico Mioso <mrkiko.rs@gmail.com>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ drivers/net/usb/cdc_mbim.c | 2 +-
+ drivers/net/usb/cdc_ncm.c | 61 ++++++++++++++++++++++++++++++++++++----
+ drivers/net/usb/huawei_cdc_ncm.c | 7 +++--
+ include/linux/usb/cdc_ncm.h | 7 ++++-
+ 4 files changed, 67 insertions(+), 10 deletions(-)
+
+--- a/drivers/net/usb/cdc_mbim.c
++++ b/drivers/net/usb/cdc_mbim.c
+@@ -158,7 +158,7 @@ static int cdc_mbim_bind(struct usbnet *
+ if (!cdc_ncm_comm_intf_is_mbim(intf->cur_altsetting))
+ goto err;
+
+- ret = cdc_ncm_bind_common(dev, intf, data_altsetting);
++ ret = cdc_ncm_bind_common(dev, intf, data_altsetting, 0);
+ if (ret)
+ goto err;
+
+--- 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->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 *d
+ 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
+ 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
+ }
+
+ /* 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
+ 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_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
+ 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
+ /* 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
+--- a/drivers/net/usb/huawei_cdc_ncm.c
++++ b/drivers/net/usb/huawei_cdc_ncm.c
+@@ -73,11 +73,14 @@ static int huawei_cdc_ncm_bind(struct us
+ struct usb_driver *subdriver = ERR_PTR(-ENODEV);
+ int ret = -ENODEV;
+ struct huawei_cdc_ncm_state *drvstate = (void *)&usbnet_dev->data;
++ int drvflags = 0;
+
+ /* altsetting should always be 1 for NCM devices - so we hard-coded
+- * it here
++ * it here. Some huawei devices will need the NDP part of the NCM package to
++ * be at the end of the frame.
+ */
+- ret = cdc_ncm_bind_common(usbnet_dev, intf, 1);
++ drvflags |= CDC_NCM_FLAG_NDP_TO_END;
++ ret = cdc_ncm_bind_common(usbnet_dev, intf, 1, drvflags);
+ if (ret)
+ goto err;
+
+--- a/include/linux/usb/cdc_ncm.h
++++ b/include/linux/usb/cdc_ncm.h
+@@ -80,6 +80,9 @@
+ #define CDC_NCM_TIMER_INTERVAL_MIN 5UL
+ #define CDC_NCM_TIMER_INTERVAL_MAX (U32_MAX / NSEC_PER_USEC)
+
++/* Driver flags */
++#define CDC_NCM_FLAG_NDP_TO_END 0x02 /* NDP is placed at end of frame */
++
+ #define cdc_ncm_comm_intf_is_mbim(x) ((x)->desc.bInterfaceSubClass == USB_CDC_SUBCLASS_MBIM && \
+ (x)->desc.bInterfaceProtocol == USB_CDC_PROTO_NONE)
+ #define cdc_ncm_data_intf_is_mbim(x) ((x)->desc.bInterfaceProtocol == USB_CDC_MBIM_PROTO_NTB)
+@@ -103,9 +106,11 @@ struct cdc_ncm_ctx {
+
+ spinlock_t mtx;
+ atomic_t stop;
++ int drvflags;
+
+ u32 timer_interval;
+ u32 max_ndp_size;
++ struct usb_cdc_ncm_ndp16 *delayed_ndp16;
+
+ u32 tx_timer_pending;
+ u32 tx_curr_frame_num;
+@@ -133,7 +138,7 @@ struct cdc_ncm_ctx {
+ };
+
+ u8 cdc_ncm_select_altsetting(struct usb_interface *intf);
+-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);
+ void cdc_ncm_unbind(struct usbnet *dev, struct usb_interface *intf);
+ struct sk_buff *cdc_ncm_fill_tx_frame(struct usbnet *dev, struct sk_buff *skb, __le32 sign);
+ int cdc_ncm_rx_verify_nth16(struct cdc_ncm_ctx *ctx, struct sk_buff *skb_in);
--- /dev/null
+From 4a0e3e989d66bb7204b163d9cfaa7fa96d0f2023 Mon Sep 17 00:00:00 2001
+From: Enrico Mioso <mrkiko.rs@gmail.com>
+Date: Wed, 8 Jul 2015 13:05:57 +0200
+Subject: [PATCH] cdc_ncm: Add support for moving NDP to end of NCM frame
+
+NCM specs are not actually mandating a specific position in the frame for
+the NDP (Network Datagram Pointer). However, some Huawei devices will
+ignore our aggregates if it is not placed after the datagrams it points
+to. Add support for doing just this, in a per-device configurable way.
+While at it, update NCM subdrivers, disabling this functionality in all of
+them, except in huawei_cdc_ncm where it is enabled instead.
+We aren't making any distinction between different Huawei NCM devices,
+based on what the vendor driver does. Standard NCM devices are left
+unaffected: if they are compliant, they should be always usable, still
+stay on the safe side.
+
+This change has been tested and working with a Huawei E3131 device (which
+works regardless of NDP position), a Huawei E3531 (also working both
+ways) and an E3372 (which mandates NDP to be after indexed datagrams).
+
+V1->V2:
+- corrected wrong NDP acronym definition
+- fixed possible NULL pointer dereference
+- patch cleanup
+V2->V3:
+- Properly account for the NDP size when writing new packets to SKB
+
+Signed-off-by: Enrico Mioso <mrkiko.rs@gmail.com>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ drivers/net/usb/cdc_mbim.c | 2 +-
+ drivers/net/usb/cdc_ncm.c | 61 ++++++++++++++++++++++++++++++++++++----
+ drivers/net/usb/huawei_cdc_ncm.c | 7 +++--
+ include/linux/usb/cdc_ncm.h | 7 ++++-
+ 4 files changed, 67 insertions(+), 10 deletions(-)
+
+--- a/drivers/net/usb/cdc_mbim.c
++++ b/drivers/net/usb/cdc_mbim.c
+@@ -158,7 +158,7 @@ static int cdc_mbim_bind(struct usbnet *
+ if (!cdc_ncm_comm_intf_is_mbim(intf->cur_altsetting))
+ goto err;
+
+- ret = cdc_ncm_bind_common(dev, intf, data_altsetting);
++ ret = cdc_ncm_bind_common(dev, intf, data_altsetting, 0);
+ if (ret)
+ goto err;
+
+--- 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->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 *d
+ 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
+ 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
+ }
+
+ /* 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
+ 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_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
+ 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
+ /* 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
+--- a/drivers/net/usb/huawei_cdc_ncm.c
++++ b/drivers/net/usb/huawei_cdc_ncm.c
+@@ -73,11 +73,14 @@ static int huawei_cdc_ncm_bind(struct us
+ struct usb_driver *subdriver = ERR_PTR(-ENODEV);
+ int ret = -ENODEV;
+ struct huawei_cdc_ncm_state *drvstate = (void *)&usbnet_dev->data;
++ int drvflags = 0;
+
+ /* altsetting should always be 1 for NCM devices - so we hard-coded
+- * it here
++ * it here. Some huawei devices will need the NDP part of the NCM package to
++ * be at the end of the frame.
+ */
+- ret = cdc_ncm_bind_common(usbnet_dev, intf, 1);
++ drvflags |= CDC_NCM_FLAG_NDP_TO_END;
++ ret = cdc_ncm_bind_common(usbnet_dev, intf, 1, drvflags);
+ if (ret)
+ goto err;
+
+--- a/include/linux/usb/cdc_ncm.h
++++ b/include/linux/usb/cdc_ncm.h
+@@ -80,6 +80,9 @@
+ #define CDC_NCM_TIMER_INTERVAL_MIN 5UL
+ #define CDC_NCM_TIMER_INTERVAL_MAX (U32_MAX / NSEC_PER_USEC)
+
++/* Driver flags */
++#define CDC_NCM_FLAG_NDP_TO_END 0x02 /* NDP is placed at end of frame */
++
+ #define cdc_ncm_comm_intf_is_mbim(x) ((x)->desc.bInterfaceSubClass == USB_CDC_SUBCLASS_MBIM && \
+ (x)->desc.bInterfaceProtocol == USB_CDC_PROTO_NONE)
+ #define cdc_ncm_data_intf_is_mbim(x) ((x)->desc.bInterfaceProtocol == USB_CDC_MBIM_PROTO_NTB)
+@@ -103,9 +106,11 @@ struct cdc_ncm_ctx {
+
+ spinlock_t mtx;
+ atomic_t stop;
++ int drvflags;
+
+ u32 timer_interval;
+ u32 max_ndp_size;
++ struct usb_cdc_ncm_ndp16 *delayed_ndp16;
+
+ u32 tx_timer_pending;
+ u32 tx_curr_frame_num;
+@@ -133,7 +138,7 @@ struct cdc_ncm_ctx {
+ };
+
+ u8 cdc_ncm_select_altsetting(struct usb_interface *intf);
+-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);
+ void cdc_ncm_unbind(struct usbnet *dev, struct usb_interface *intf);
+ struct sk_buff *cdc_ncm_fill_tx_frame(struct usbnet *dev, struct sk_buff *skb, __le32 sign);
+ int cdc_ncm_rx_verify_nth16(struct cdc_ncm_ctx *ctx, struct sk_buff *skb_in);
projects / openwrt / staging / ynezz.git / commitdiff