[NET]: Move generic skbuff stuff from XFRM code to generic code

Move generic skbuff stuff from XFRM code to generic code so that
AF_RXRPC can use it too.

The kdoc comments I've attached to the functions needs to be checked
by whoever wrote them as I had to make some guesses about the workings
of these functions.

Signed-off-By: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 0 insertions, 169 deletions

diff --git a/net/xfrm/xfrm_algo.c b/net/xfrm/xfrm_algo.c
index f373a8a7d9c8..6249a9405bb8 100644
--- a/net/xfrm/xfrm_algo.c
+++ b/net/xfrm/xfrm_algo.c
@@ -612,175 +612,6 @@ EXPORT_SYMBOL_GPL(skb_icv_walk);
 
 #if defined(CONFIG_INET_ESP) || defined(CONFIG_INET_ESP_MODULE) || defined(CONFIG_INET6_ESP) || defined(CONFIG_INET6_ESP_MODULE)
 
-/* Looking generic it is not used in another places. */
-
-int
-skb_to_sgvec(struct sk_buff *skb, struct scatterlist *sg, int offset, int len)
-{
-        int start = skb_headlen(skb);
-        int i, copy = start - offset;
-        int elt = 0;
-
-        if (copy > 0) {
-                if (copy > len)
-                        copy = len;
-                sg[elt].page = virt_to_page(skb->data + offset);
-                sg[elt].offset = (unsigned long)(skb->data + offset) % PAGE_SIZE;
-                sg[elt].length = copy;
-                elt++;
-                if ((len -= copy) == 0)
-                        return elt;
-                offset += copy;
-        }
-
-        for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
-                int end;
-
-                BUG_TRAP(start <= offset + len);
-
-                end = start + skb_shinfo(skb)->frags[i].size;
-                if ((copy = end - offset) > 0) {
-                        skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
-
-                        if (copy > len)
-                                copy = len;
-                        sg[elt].page = frag->page;
-                        sg[elt].offset = frag->page_offset+offset-start;
-                        sg[elt].length = copy;
-                        elt++;
-                        if (!(len -= copy))
-                                return elt;
-                        offset += copy;
-                }
-                start = end;
-        }
-
-        if (skb_shinfo(skb)->frag_list) {
-                struct sk_buff *list = skb_shinfo(skb)->frag_list;
-
-                for (; list; list = list->next) {
-                        int end;
-
-                        BUG_TRAP(start <= offset + len);
-
-                        end = start + list->len;
-                        if ((copy = end - offset) > 0) {
-                                if (copy > len)
-                                        copy = len;
-                                elt += skb_to_sgvec(list, sg+elt, offset - start, copy);
-                                if ((len -= copy) == 0)
-                                        return elt;
-                                offset += copy;
-                        }
-                        start = end;
-                }
-        }
-        BUG_ON(len);
-        return elt;
-}
-EXPORT_SYMBOL_GPL(skb_to_sgvec);
-
-/* Check that skb data bits are writable. If they are not, copy data
- * to newly created private area. If "tailbits" is given, make sure that
- * tailbits bytes beyond current end of skb are writable.
- *
- * Returns amount of elements of scatterlist to load for subsequent
- * transformations and pointer to writable trailer skb.
- */
-
-int skb_cow_data(struct sk_buff *skb, int tailbits, struct sk_buff **trailer)
-{
-        int copyflag;
-        int elt;
-        struct sk_buff *skb1, **skb_p;
-
-        /* If skb is cloned or its head is paged, reallocate
-         * head pulling out all the pages (pages are considered not writable
-         * at the moment even if they are anonymous).
-         */
-        if ((skb_cloned(skb) || skb_shinfo(skb)->nr_frags) &&
-            __pskb_pull_tail(skb, skb_pagelen(skb)-skb_headlen(skb)) == NULL)
-                return -ENOMEM;
-
-        /* Easy case. Most of packets will go this way. */
-        if (!skb_shinfo(skb)->frag_list) {
-                /* A little of trouble, not enough of space for trailer.
-                 * This should not happen, when stack is tuned to generate
-                 * good frames. OK, on miss we reallocate and reserve even more
-                 * space, 128 bytes is fair. */
-
-                if (skb_tailroom(skb) < tailbits &&
-                    pskb_expand_head(skb, 0, tailbits-skb_tailroom(skb)+128, GFP_ATOMIC))
-                        return -ENOMEM;
-
-                /* Voila! */
-                *trailer = skb;
-                return 1;
-        }
-
-        /* Misery. We are in troubles, going to mincer fragments... */
-
-        elt = 1;
-        skb_p = &skb_shinfo(skb)->frag_list;
-        copyflag = 0;
-
-        while ((skb1 = *skb_p) != NULL) {
-                int ntail = 0;
-
-                /* The fragment is partially pulled by someone,
-                 * this can happen on input. Copy it and everything
-                 * after it. */
-
-                if (skb_shared(skb1))
-                        copyflag = 1;
-
-                /* If the skb is the last, worry about trailer. */
-
-                if (skb1->next == NULL && tailbits) {
-                        if (skb_shinfo(skb1)->nr_frags ||
-                            skb_shinfo(skb1)->frag_list ||
-                            skb_tailroom(skb1) < tailbits)
-                                ntail = tailbits + 128;
-                }
-
-                if (copyflag ||
-                    skb_cloned(skb1) ||
-                    ntail ||
-                    skb_shinfo(skb1)->nr_frags ||
-                    skb_shinfo(skb1)->frag_list) {
-                        struct sk_buff *skb2;
-
-                        /* Fuck, we are miserable poor guys... */
-                        if (ntail == 0)
-                                skb2 = skb_copy(skb1, GFP_ATOMIC);
-                        else
-                                skb2 = skb_copy_expand(skb1,
-                                                       skb_headroom(skb1),
-                                                       ntail,
-                                                       GFP_ATOMIC);
-                        if (unlikely(skb2 == NULL))
-                                return -ENOMEM;
-
-                        if (skb1->sk)
-                                skb_set_owner_w(skb2, skb1->sk);
-
-                        /* Looking around. Are we still alive?
-                         * OK, link new skb, drop old one */
-
-                        skb2->next = skb1->next;
-                        *skb_p = skb2;
-                        kfree_skb(skb1);
-                        skb1 = skb2;
-                }
-                elt++;
-                *trailer = skb1;
-                skb_p = &skb1->next;
-        }
-
-        return elt;
-}
-EXPORT_SYMBOL_GPL(skb_cow_data);
-
 void *pskb_put(struct sk_buff *skb, struct sk_buff *tail, int len)
 {
         if (tail != skb) {