SKB_COW(9) Linux Networking SKB_COW(9)NAME
skb_cow - copy header of skb when it is required
int skb_cow(struct sk_buff * skb, unsigned int headroom);
buffer to cow
If the skb passed lacks sufficient headroom or its data part is shared, data is reallocated. If reallocation fails, an error is returned
and original skb is not changed.
The result is skb with writable area skb->head...skb->tail and at least headroom of space at head.
COPYRIGHT Kernel Hackers Manual 3.10 June 2014 SKB_COW(9)
Check Out this Related Man Page
WIMAX_MSG_ALLOC(9) Linux Networking WIMAX_MSG_ALLOC(9)NAME
wimax_msg_alloc - Create a new skb for sending a message to userspace
struct sk_buff * wimax_msg_alloc(struct wimax_dev * wimax_dev, const char * pipe_name, const void * msg, size_t size, gfp_t gfp_flags);
WiMAX device descriptor
"named pipe" the message will be sent to
pointer to the message data to send
size of the message to send (in bytes), including the header.
flags for memory allocation.
0 if ok, negative errno code on error
Allocates an skb that will contain the message to send to user space over the messaging pipe and initializes it, copying the payload.
Once this call is done, you can deliver it with wimax_msg_send.
Don't use skb_push/skb_pull/skb_reserve on the skb, as wimax_msg_send depends on skb->data being placed at the beginning of the user
Unlike other WiMAX stack calls, this call can be used way early, even before wimax_dev_add is called, as long as the wimax_dev->net_dev
pointer is set to point to a proper net_dev. This is so that drivers can use it early in case they need to send stuff around or communicate
with user space.
COPYRIGHT Kernel Hackers Manual 2.6. July 2010 WIMAX_MSG_ALLOC(9)
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