static void cdc_ncm_txpath_bh(unsigned long param)
{
struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)param;
spin_lock_bh(&ctx->mtx);
if (ctx->tx_timer_pending != 0) {
ctx->tx_timer_pending--;
cdc_ncm_tx_timeout_start(ctx);
spin_unlock_bh(&ctx->mtx);
} else if (ctx->netdev != NULL) {
spin_unlock_bh(&ctx->mtx);
netif_tx_lock_bh(ctx->netdev);
usbnet_start_xmit(NULL, ctx->netdev);
netif_tx_unlock_bh(ctx->netdev);
} else {
spin_unlock_bh(&ctx->mtx);
}
}
static void cdc_ncm_txpath_bh(unsigned long param)
{
struct if_usb_devdata *pipe_data = (struct if_usb_devdata *)param;
struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)pipe_data->sedata;
if (!ctx)
return;
spin_lock_bh(&ctx->mtx);
if (ctx->tx_timer_pending != 0) {
ctx->tx_timer_pending--;
cdc_ncm_tx_timeout_start(ctx);
spin_unlock_bh(&ctx->mtx);
} else if (pipe_data->iod->ndev != NULL) {
spin_unlock_bh(&ctx->mtx);
netif_tx_lock_bh(pipe_data->iod->ndev);
usb_tx_skb(pipe_data, NULL);
netif_tx_unlock_bh(pipe_data->iod->ndev);
} else {
spin_unlock_bh(&ctx->mtx);
}
}
struct sk_buff *
cdc_ncm_fill_tx_frame(struct cdc_ncm_ctx *ctx, struct sk_buff *skb, __le32 sign)
{
struct usb_cdc_ncm_nth16 *nth16;
struct usb_cdc_ncm_ndp16 *ndp16;
struct sk_buff *skb_out;
u16 n = 0, index, ndplen;
u8 ready2send = 0;
/* if there is a remaining skb, it gets priority */
if (skb != NULL) {
swap(skb, ctx->tx_rem_skb);
swap(sign, ctx->tx_rem_sign);
} else {
ready2send = 1;
}
/* check if we are resuming an OUT skb */
skb_out = ctx->tx_curr_skb;
/* allocate a new OUT skb */
if (!skb_out) {
skb_out = alloc_skb((ctx->tx_max + 1), GFP_ATOMIC);
if (skb_out == NULL) {
if (skb != NULL) {
dev_kfree_skb_any(skb);
ctx->netdev->stats.tx_dropped++;
}
goto exit_no_skb;
}
/* fill out the initial 16-bit NTB header */
nth16 = (struct usb_cdc_ncm_nth16 *)memset(skb_put(skb_out, sizeof(struct usb_cdc_ncm_nth16)), 0, sizeof(struct usb_cdc_ncm_nth16));
nth16->dwSignature = cpu_to_le32(USB_CDC_NCM_NTH16_SIGN);
nth16->wHeaderLength = cpu_to_le16(sizeof(struct usb_cdc_ncm_nth16));
nth16->wSequence = cpu_to_le16(ctx->tx_seq++);
/* count total number of frames in this NTB */
ctx->tx_curr_frame_num = 0;
}
for (n = ctx->tx_curr_frame_num; n < ctx->tx_max_datagrams; n++) {
/* send any remaining skb first */
if (skb == NULL) {
skb = ctx->tx_rem_skb;
sign = ctx->tx_rem_sign;
ctx->tx_rem_skb = NULL;
/* check for end of skb */
if (skb == NULL)
break;
}
/* get the appropriate NDP for this skb */
ndp16 = cdc_ncm_ndp(ctx, skb_out, sign, skb->len + ctx->tx_modulus + ctx->tx_remainder);
/* align beginning of next frame */
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 (n == 0) {
/* won't fit, MTU problem? */
dev_kfree_skb_any(skb);
skb = NULL;
ctx->netdev->stats.tx_dropped++;
} else {
/* no room for skb - store for later */
if (ctx->tx_rem_skb != NULL) {
dev_kfree_skb_any(ctx->tx_rem_skb);
ctx->netdev->stats.tx_dropped++;
}
ctx->tx_rem_skb = skb;
ctx->tx_rem_sign = sign;
skb = NULL;
ready2send = 1;
}
break;
}
/* calculate frame number withing this NDP */
ndplen = le16_to_cpu(ndp16->wLength);
index = (ndplen - sizeof(struct usb_cdc_ncm_ndp16)) / sizeof(struct usb_cdc_ncm_dpe16) - 1;
/* OK, add this skb */
ndp16->dpe16[index].wDatagramLength = cpu_to_le16(skb->len);
ndp16->dpe16[index].wDatagramIndex = cpu_to_le16(skb_out->len);
ndp16->wLength = cpu_to_le16(ndplen + sizeof(struct usb_cdc_ncm_dpe16));
memcpy(skb_put(skb_out, skb->len), skb->data, skb->len);
dev_kfree_skb_any(skb);
skb = NULL;
/* send now if this NDP is full */
if (index >= CDC_NCM_DPT_DATAGRAMS_MAX) {
ready2send = 1;
break;
}
}
/* free up any dangling skb */
if (skb != NULL) {
dev_kfree_skb_any(skb);
skb = NULL;
ctx->netdev->stats.tx_dropped++;
}
ctx->tx_curr_frame_num = n;
if (n == 0) {
/* wait for more frames */
/* push variables */
ctx->tx_curr_skb = skb_out;
goto exit_no_skb;
} else if ((n < ctx->tx_max_datagrams) && (ready2send == 0)) {
/* wait for more frames */
/* push variables */
ctx->tx_curr_skb = skb_out;
/* set the pending count */
if (n < CDC_NCM_RESTART_TIMER_DATAGRAM_CNT)
ctx->tx_timer_pending = CDC_NCM_TIMER_PENDING_CNT;
goto exit_no_skb;
} else {
/* frame goes out */
/* variables will be reset at next call */
}
/*
* If collected data size is less or equal CDC_NCM_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 engine to receive a full
* size NTB, than canceling DMA transfer and receiving a short packet.
*/
if (skb_out->len > CDC_NCM_MIN_TX_PKT)
/* final zero padding */
memset(skb_put(skb_out, ctx->tx_max - skb_out->len), 0, ctx->tx_max - skb_out->len);
/* do we need to prevent a ZLP? */
if (((skb_out->len % le16_to_cpu(ctx->out_ep->desc.wMaxPacketSize)) == 0) &&
(skb_out->len < le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize)) && skb_tailroom(skb_out))
*skb_put(skb_out, 1) = 0; /* force short packet */
/* set final frame length */
nth16 = (struct usb_cdc_ncm_nth16 *)skb_out->data;
nth16->wBlockLength = cpu_to_le16(skb_out->len);
/* return skb */
ctx->tx_curr_skb = NULL;
ctx->netdev->stats.tx_packets += ctx->tx_curr_frame_num;
return skb_out;
exit_no_skb:
/* Start timer, if there is a remaining skb */
if (ctx->tx_curr_skb != NULL)
cdc_ncm_tx_timeout_start(ctx);
return NULL;
}
static struct sk_buff *
cdc_ncm_fill_tx_frame(struct if_usb_devdata *pipe_data, struct sk_buff *skb)
{
struct sk_buff *skb_out;
struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)pipe_data->sedata;
u32 rem;
u32 offset;
u32 last_offset;
u16 n = 0, index;
u8 ready2send = 0;
/* if there is a remaining skb, it gets priority */
if (skb != NULL)
swap(skb, ctx->tx_rem_skb);
else
ready2send = 1;
/*
* +----------------+
* | skb_out |
* +----------------+
* ^ offset
* ^ last_offset
*/
/* check if we are resuming an OUT skb */
if (ctx->tx_curr_skb != NULL) {
/* pop variables */
skb_out = ctx->tx_curr_skb;
offset = ctx->tx_curr_offset;
last_offset = ctx->tx_curr_last_offset;
n = ctx->tx_curr_frame_num;
} else {
/* restore tx_max */
ctx->tx_max = (ctx->tx_max_setup & 0xFFF)
? ctx->tx_max_setup : ctx->tx_max_setup - 512;
retry_alloc:
skb_out = alloc_skb((ctx->tx_max + 1), GFP_ATOMIC);
if (skb_out == NULL) {
ctx->tx_max = ctx->tx_max / 2 - 256;
if (ctx->tx_max >= PAGE_SIZE - 512) {
mif_err("re-try to alloc %d\n", ctx->tx_max);
goto retry_alloc;
}
if (skb != NULL)
dev_kfree_skb_any(skb);
goto exit_no_skb;
}
/* make room for NTH and NDP */
offset = ALIGN(sizeof(struct usb_cdc_ncm_nth16),
ctx->tx_ndp_modulus) +
sizeof(struct usb_cdc_ncm_ndp16) +
(ctx->tx_max_datagrams + 1) *
sizeof(struct usb_cdc_ncm_dpe16);
/* store last valid offset before alignment */
last_offset = offset;
/* align first Datagram offset correctly */
offset = ALIGN(offset, ctx->tx_modulus) + ctx->tx_remainder;
/* zero buffer till the first IP datagram */
cdc_ncm_zero_fill(skb_out->data, 0, offset, offset);
n = 0;
ctx->tx_curr_frame_num = 0;
}
for (; n < ctx->tx_max_datagrams; n++) {
/* check if end of transmit buffer is reached */
if (offset >= ctx->tx_max) {
ready2send = 1;
break;
}
/* compute maximum buffer size */
rem = ctx->tx_max - offset;
if (skb == NULL) {
skb = ctx->tx_rem_skb;
ctx->tx_rem_skb = NULL;
/* check for end of skb */
if (skb == NULL)
break;
}
if (skb->len > rem) {
if (n == 0) {
/* won't fit, MTU problem? */
dev_kfree_skb_any(skb);
skb = NULL;
} else {
/* no room for skb - store for later */
if (ctx->tx_rem_skb != NULL)
dev_kfree_skb_any(ctx->tx_rem_skb);
ctx->tx_rem_skb = skb;
skb = NULL;
ready2send = 1;
}
break;
}
memcpy(((u8 *)skb_out->data) + offset, skb->data, skb->len);
ctx->tx_ncm.dpe16[n].wDatagramLength = cpu_to_le16(skb->len);
ctx->tx_ncm.dpe16[n].wDatagramIndex = cpu_to_le16(offset);
/* update offset */
offset += skb->len;
/* store last valid offset before alignment */
last_offset = offset;
/* align offset correctly */
offset = ALIGN(offset, ctx->tx_modulus) + ctx->tx_remainder;
/* zero padding */
cdc_ncm_zero_fill(skb_out->data, last_offset, offset,
ctx->tx_max);
dev_kfree_skb_any(skb);
skb = NULL;
}
/* free up any dangling skb */
if (skb != NULL) {
dev_kfree_skb_any(skb);
skb = NULL;
}
ctx->tx_curr_frame_num = n;
if (n == 0) {
/* wait for more frames */
/* push variables */
ctx->tx_curr_skb = skb_out;
ctx->tx_curr_offset = offset;
ctx->tx_curr_last_offset = last_offset;
goto exit_no_skb;
} else if ((n < ctx->tx_max_datagrams) && (ready2send == 0)) {
/* wait for more frames */
/* push variables */
ctx->tx_curr_skb = skb_out;
ctx->tx_curr_offset = offset;
ctx->tx_curr_last_offset = last_offset;
/* set the pending count */
if (n < CDC_NCM_RESTART_TIMER_DATAGRAM_CNT)
ctx->tx_timer_pending = CDC_NCM_TIMER_PENDING_CNT;
goto exit_no_skb;
} else {
/* frame goes out */
/* variables will be reset at next call */
}
/* check for overflow */
if (last_offset > ctx->tx_max)
last_offset = ctx->tx_max;
/* revert offset */
offset = last_offset;
/*
* If collected data size is less or equal CDC_NCM_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 engine to receive a full
* size NTB, than canceling DMA transfer and receiving a short packet.
*/
if (offset > CDC_NCM_MIN_TX_PKT)
offset = ctx->tx_max;
/* final zero padding */
cdc_ncm_zero_fill(skb_out->data, last_offset, offset, ctx->tx_max);
/* store last offset */
last_offset = offset;
if (((last_offset < ctx->tx_max) && ((last_offset %
le16_to_cpu(ctx->out_ep->desc.wMaxPacketSize)) == 0)) ||
(((last_offset == ctx->tx_max) && ((ctx->tx_max %
le16_to_cpu(ctx->out_ep->desc.wMaxPacketSize)) == 0)) &&
(ctx->tx_max < le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize)))) {
/* force short packet */
*(((u8 *)skb_out->data) + last_offset) = 0;
last_offset++;
}
/* zero the rest of the DPEs plus the last NULL entry */
for (; n <= CDC_NCM_DPT_DATAGRAMS_MAX; n++) {
ctx->tx_ncm.dpe16[n].wDatagramLength = 0;
ctx->tx_ncm.dpe16[n].wDatagramIndex = 0;
}
/* fill out 16-bit NTB header */
ctx->tx_ncm.nth16.dwSignature = cpu_to_le32(USB_CDC_NCM_NTH16_SIGN);
ctx->tx_ncm.nth16.wHeaderLength =
cpu_to_le16(sizeof(ctx->tx_ncm.nth16));
ctx->tx_ncm.nth16.wSequence = cpu_to_le16(ctx->tx_seq);
ctx->tx_ncm.nth16.wBlockLength = cpu_to_le16(last_offset);
index = ALIGN(sizeof(struct usb_cdc_ncm_nth16), ctx->tx_ndp_modulus);
ctx->tx_ncm.nth16.wNdpIndex = cpu_to_le16(index);
memcpy(skb_out->data, &(ctx->tx_ncm.nth16), sizeof(ctx->tx_ncm.nth16));
ctx->tx_seq++;
/* fill out 16-bit NDP table */
ctx->tx_ncm.ndp16.dwSignature =
cpu_to_le32(USB_CDC_NCM_NDP16_NOCRC_SIGN);
rem = sizeof(ctx->tx_ncm.ndp16) + ((ctx->tx_curr_frame_num + 1) *
sizeof(struct usb_cdc_ncm_dpe16));
ctx->tx_ncm.ndp16.wLength = cpu_to_le16(rem);
ctx->tx_ncm.ndp16.wNextNdpIndex = 0; /* reserved */
memcpy(((u8 *)skb_out->data) + index,
&(ctx->tx_ncm.ndp16),
sizeof(ctx->tx_ncm.ndp16));
memcpy(((u8 *)skb_out->data) + index + sizeof(ctx->tx_ncm.ndp16),
&(ctx->tx_ncm.dpe16),
(ctx->tx_curr_frame_num + 1) *
sizeof(struct usb_cdc_ncm_dpe16));
/* set frame length */
skb_put(skb_out, last_offset);
/* return skb */
ctx->tx_curr_skb = NULL;
pipe_data->iod->ndev->stats.tx_packets += ctx->tx_curr_frame_num;
return skb_out;
exit_no_skb:
/* Start timer, if there is a remaining skb */
if (ctx->tx_curr_skb != NULL)
cdc_ncm_tx_timeout_start(ctx);
return NULL;
}
