diff options
| author | Thomas Graf <tgraf@suug.ch> | 2005-06-23 20:59:51 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2005-06-23 20:59:51 -0700 |
| commit | 677e90eda3bd8cfde0b748daaa46476162a03950 (patch) | |
| tree | 4b40614cf9cd125883d0430467be9172997ca184 /include | |
| parent | 6408f79cce401e1bfecf923e7156f84f96e021e3 (diff) | |
[NET]: Zerocopy sequential reading of skb data
Implements sequential reading for both linear and non-linear
skb data at zerocopy cost. The data is returned in chunks of
arbitary length, therefore random access is not possible.
Usage:
from := 0
to := 128
state := undef
data := undef
len := undef
consumed := 0
skb_prepare_seq_read(skb, from, to, &state)
while (len = skb_seq_read(consumed, &data, &state)) != 0 do
/* do something with 'data' of length 'len' */
if abort then
/* abort read if we don't wait for
* skb_seq_read() to return 0 */
skb_abort_seq_read(&state)
return
endif
/* not necessary to consume all of 'len' */
consumed += len
done
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/skbuff.h | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index d7c839a2184..171a37dff83 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -321,6 +321,24 @@ extern void skb_over_panic(struct sk_buff *skb, int len, extern void skb_under_panic(struct sk_buff *skb, int len, void *here); +struct skb_seq_state +{ + __u32 lower_offset; + __u32 upper_offset; + __u32 frag_idx; + __u32 stepped_offset; + struct sk_buff *root_skb; + struct sk_buff *cur_skb; + __u8 *frag_data; +}; + +extern void skb_prepare_seq_read(struct sk_buff *skb, + unsigned int from, unsigned int to, + struct skb_seq_state *st); +extern unsigned int skb_seq_read(unsigned int consumed, const u8 **data, + struct skb_seq_state *st); +extern void skb_abort_seq_read(struct skb_seq_state *st); + /* Internal */ #define skb_shinfo(SKB) ((struct skb_shared_info *)((SKB)->end)) |