diff options
Diffstat (limited to 'net/core/skbuff.c')
| -rw-r--r-- | net/core/skbuff.c | 75 |
1 files changed, 75 insertions, 0 deletions
diff --git a/net/core/skbuff.c b/net/core/skbuff.c index ef9d46b91eb..95501e40100 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -176,6 +176,8 @@ struct sk_buff *__alloc_skb(unsigned int size, gfp_t gfp_mask, skb_shinfo(skb)->tso_size = 0; skb_shinfo(skb)->tso_segs = 0; skb_shinfo(skb)->frag_list = NULL; + skb_shinfo(skb)->ufo_size = 0; + skb_shinfo(skb)->ip6_frag_id = 0; out: return skb; nodata: @@ -1696,6 +1698,78 @@ unsigned int skb_find_text(struct sk_buff *skb, unsigned int from, return textsearch_find(config, state); } +/** + * skb_append_datato_frags: - append the user data to a skb + * @sk: sock structure + * @skb: skb structure to be appened with user data. + * @getfrag: call back function to be used for getting the user data + * @from: pointer to user message iov + * @length: length of the iov message + * + * Description: This procedure append the user data in the fragment part + * of the skb if any page alloc fails user this procedure returns -ENOMEM + */ +int skb_append_datato_frags(struct sock *sk, struct sk_buff *skb, + int getfrag(void *from, char *to, int offset, + int len, int odd, struct sk_buff *skb), + void *from, int length) +{ + int frg_cnt = 0; + skb_frag_t *frag = NULL; + struct page *page = NULL; + int copy, left; + int offset = 0; + int ret; + + do { + /* Return error if we don't have space for new frag */ + frg_cnt = skb_shinfo(skb)->nr_frags; + if (frg_cnt >= MAX_SKB_FRAGS) + return -EFAULT; + + /* allocate a new page for next frag */ + page = alloc_pages(sk->sk_allocation, 0); + + /* If alloc_page fails just return failure and caller will + * free previous allocated pages by doing kfree_skb() + */ + if (page == NULL) + return -ENOMEM; + + /* initialize the next frag */ + sk->sk_sndmsg_page = page; + sk->sk_sndmsg_off = 0; + skb_fill_page_desc(skb, frg_cnt, page, 0, 0); + skb->truesize += PAGE_SIZE; + atomic_add(PAGE_SIZE, &sk->sk_wmem_alloc); + + /* get the new initialized frag */ + frg_cnt = skb_shinfo(skb)->nr_frags; + frag = &skb_shinfo(skb)->frags[frg_cnt - 1]; + + /* copy the user data to page */ + left = PAGE_SIZE - frag->page_offset; + copy = (length > left)? left : length; + + ret = getfrag(from, (page_address(frag->page) + + frag->page_offset + frag->size), + offset, copy, 0, skb); + if (ret < 0) + return -EFAULT; + + /* copy was successful so update the size parameters */ + sk->sk_sndmsg_off += copy; + frag->size += copy; + skb->len += copy; + skb->data_len += copy; + offset += copy; + length -= copy; + + } while (length > 0); + + return 0; +} + void __init skb_init(void) { skbuff_head_cache = kmem_cache_create("skbuff_head_cache", @@ -1747,3 +1821,4 @@ EXPORT_SYMBOL(skb_prepare_seq_read); EXPORT_SYMBOL(skb_seq_read); EXPORT_SYMBOL(skb_abort_seq_read); EXPORT_SYMBOL(skb_find_text); +EXPORT_SYMBOL(skb_append_datato_frags); |