* Buffers may only be allocated from interrupts using a @gfp_mask of
* %GFP_ATOMIC.
*/
+#ifndef CONFIG_HAVE_ARCH_ALLOC_SKB
struct sk_buff *__alloc_skb(unsigned int size, gfp_t gfp_mask,
int fclone)
{
shinfo = skb_shinfo(skb);
atomic_set(&shinfo->dataref, 1);
shinfo->nr_frags = 0;
- shinfo->tso_size = 0;
- shinfo->tso_segs = 0;
- shinfo->ufo_size = 0;
+ shinfo->gso_size = 0;
+ shinfo->gso_segs = 0;
+ shinfo->gso_type = 0;
shinfo->ip6_frag_id = 0;
shinfo->frag_list = NULL;
skb = NULL;
goto out;
}
+#endif /* !CONFIG_HAVE_ARCH_ALLOC_SKB */
/**
* alloc_skb_from_cache - allocate a network buffer
*/
struct sk_buff *alloc_skb_from_cache(kmem_cache_t *cp,
unsigned int size,
- gfp_t gfp_mask)
+ gfp_t gfp_mask,
+ int fclone)
{
+ kmem_cache_t *cache;
+ struct skb_shared_info *shinfo;
struct sk_buff *skb;
u8 *data;
+ cache = fclone ? skbuff_fclone_cache : skbuff_head_cache;
+
/* Get the HEAD */
- skb = kmem_cache_alloc(skbuff_head_cache,
- gfp_mask & ~__GFP_DMA);
+ skb = kmem_cache_alloc(cache, gfp_mask & ~__GFP_DMA);
if (!skb)
goto out;
skb->data = data;
skb->tail = data;
skb->end = data + size;
+ /* make sure we initialize shinfo sequentially */
+ shinfo = skb_shinfo(skb);
+ atomic_set(&shinfo->dataref, 1);
+ shinfo->nr_frags = 0;
+ shinfo->gso_size = 0;
+ shinfo->gso_segs = 0;
+ shinfo->gso_type = 0;
+ shinfo->ip6_frag_id = 0;
+ shinfo->frag_list = NULL;
- atomic_set(&(skb_shinfo(skb)->dataref), 1);
- skb_shinfo(skb)->nr_frags = 0;
- skb_shinfo(skb)->tso_size = 0;
- skb_shinfo(skb)->tso_segs = 0;
- skb_shinfo(skb)->frag_list = NULL;
+ if (fclone) {
+ struct sk_buff *child = skb + 1;
+ atomic_t *fclone_ref = (atomic_t *) (child + 1);
+
+ skb->fclone = SKB_FCLONE_ORIG;
+ atomic_set(fclone_ref, 1);
+
+ child->fclone = SKB_FCLONE_UNAVAILABLE;
+ }
out:
return skb;
nodata:
- kmem_cache_free(skbuff_head_cache, skb);
+ kmem_cache_free(cache, skb);
skb = NULL;
goto out;
}
-static void skb_drop_fraglist(struct sk_buff *skb)
+static void skb_drop_list(struct sk_buff **listp)
{
- struct sk_buff *list = skb_shinfo(skb)->frag_list;
+ struct sk_buff *list = *listp;
- skb_shinfo(skb)->frag_list = NULL;
+ *listp = NULL;
do {
struct sk_buff *this = list;
} while (list);
}
+static inline void skb_drop_fraglist(struct sk_buff *skb)
+{
+ skb_drop_list(&skb_shinfo(skb)->frag_list);
+}
+
static void skb_clone_fraglist(struct sk_buff *skb)
{
struct sk_buff *list;
C(local_df);
n->cloned = 1;
n->nohdr = 0;
+#ifdef CONFIG_XEN
+ C(proto_data_valid);
+ C(proto_csum_blank);
+#endif
C(pkt_type);
C(ip_summed);
C(priority);
new->tc_index = old->tc_index;
#endif
atomic_set(&new->users, 1);
- skb_shinfo(new)->tso_size = skb_shinfo(old)->tso_size;
- skb_shinfo(new)->tso_segs = skb_shinfo(old)->tso_segs;
+ skb_shinfo(new)->gso_size = skb_shinfo(old)->gso_size;
+ skb_shinfo(new)->gso_segs = skb_shinfo(old)->gso_segs;
+ skb_shinfo(new)->gso_type = skb_shinfo(old)->gso_type;
}
/**
return nskb;
}
-/* Trims skb to length len. It can change skb pointers, if "realloc" is 1.
- * If realloc==0 and trimming is impossible without change of data,
- * it is BUG().
+/* Trims skb to length len. It can change skb pointers.
*/
-int ___pskb_trim(struct sk_buff *skb, unsigned int len, int realloc)
+int ___pskb_trim(struct sk_buff *skb, unsigned int len)
{
+ struct sk_buff **fragp;
+ struct sk_buff *frag;
int offset = skb_headlen(skb);
int nfrags = skb_shinfo(skb)->nr_frags;
int i;
+ int err;
- for (i = 0; i < nfrags; i++) {
+ if (skb_cloned(skb) &&
+ unlikely((err = pskb_expand_head(skb, 0, 0, GFP_ATOMIC))))
+ return err;
+
+ i = 0;
+ if (offset >= len)
+ goto drop_pages;
+
+ for (; i < nfrags; i++) {
int end = offset + skb_shinfo(skb)->frags[i].size;
- if (end > len) {
- if (skb_cloned(skb)) {
- BUG_ON(!realloc);
- if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
- return -ENOMEM;
- }
- if (len <= offset) {
- put_page(skb_shinfo(skb)->frags[i].page);
- skb_shinfo(skb)->nr_frags--;
- } else {
- skb_shinfo(skb)->frags[i].size = len - offset;
- }
+
+ if (end < len) {
+ offset = end;
+ continue;
}
- offset = end;
+
+ skb_shinfo(skb)->frags[i++].size = len - offset;
+
+drop_pages:
+ skb_shinfo(skb)->nr_frags = i;
+
+ for (; i < nfrags; i++)
+ put_page(skb_shinfo(skb)->frags[i].page);
+
+ if (skb_shinfo(skb)->frag_list)
+ skb_drop_fraglist(skb);
+ goto done;
}
- if (offset < len) {
+ for (fragp = &skb_shinfo(skb)->frag_list; (frag = *fragp);
+ fragp = &frag->next) {
+ int end = offset + frag->len;
+
+ if (skb_shared(frag)) {
+ struct sk_buff *nfrag;
+
+ nfrag = skb_clone(frag, GFP_ATOMIC);
+ if (unlikely(!nfrag))
+ return -ENOMEM;
+
+ nfrag->next = frag->next;
+ kfree_skb(frag);
+ frag = nfrag;
+ *fragp = frag;
+ }
+
+ if (end < len) {
+ offset = end;
+ continue;
+ }
+
+ if (end > len &&
+ unlikely((err = pskb_trim(frag, len - offset))))
+ return err;
+
+ if (frag->next)
+ skb_drop_list(&frag->next);
+ break;
+ }
+
+done:
+ if (len > skb_headlen(skb)) {
skb->data_len -= skb->len - len;
skb->len = len;
} else {
- if (len <= skb_headlen(skb)) {
- skb->len = len;
- skb->data_len = 0;
- skb->tail = skb->data + len;
- if (skb_shinfo(skb)->frag_list && !skb_cloned(skb))
- skb_drop_fraglist(skb);
- } else {
- skb->data_len -= skb->len - len;
- skb->len = len;
- }
+ skb->len = len;
+ skb->data_len = 0;
+ skb->tail = skb->data + len;
}
return 0;
EXPORT_SYMBOL_GPL(skb_pull_rcsum);
+/**
+ * skb_segment - Perform protocol segmentation on skb.
+ * @skb: buffer to segment
+ * @features: features for the output path (see dev->features)
+ *
+ * This function performs segmentation on the given skb. It returns
+ * the segment at the given position. It returns NULL if there are
+ * no more segments to generate, or when an error is encountered.
+ */
+struct sk_buff *skb_segment(struct sk_buff *skb, int features)
+{
+ struct sk_buff *segs = NULL;
+ struct sk_buff *tail = NULL;
+ unsigned int mss = skb_shinfo(skb)->gso_size;
+ unsigned int doffset = skb->data - skb->mac.raw;
+ unsigned int offset = doffset;
+ unsigned int headroom;
+ unsigned int len;
+ int sg = features & NETIF_F_SG;
+ int nfrags = skb_shinfo(skb)->nr_frags;
+ int err = -ENOMEM;
+ int i = 0;
+ int pos;
+
+ __skb_push(skb, doffset);
+ headroom = skb_headroom(skb);
+ pos = skb_headlen(skb);
+
+ do {
+ struct sk_buff *nskb;
+ skb_frag_t *frag;
+ int hsize, nsize;
+ int k;
+ int size;
+
+ len = skb->len - offset;
+ if (len > mss)
+ len = mss;
+
+ hsize = skb_headlen(skb) - offset;
+ if (hsize < 0)
+ hsize = 0;
+ nsize = hsize + doffset;
+ if (nsize > len + doffset || !sg)
+ nsize = len + doffset;
+
+ nskb = alloc_skb(nsize + headroom, GFP_ATOMIC);
+ if (unlikely(!nskb))
+ goto err;
+
+ if (segs)
+ tail->next = nskb;
+ else
+ segs = nskb;
+ tail = nskb;
+
+ nskb->dev = skb->dev;
+ nskb->priority = skb->priority;
+ nskb->protocol = skb->protocol;
+ nskb->dst = dst_clone(skb->dst);
+ memcpy(nskb->cb, skb->cb, sizeof(skb->cb));
+ nskb->pkt_type = skb->pkt_type;
+ nskb->mac_len = skb->mac_len;
+
+ skb_reserve(nskb, headroom);
+ nskb->mac.raw = nskb->data;
+ nskb->nh.raw = nskb->data + skb->mac_len;
+ nskb->h.raw = nskb->nh.raw + (skb->h.raw - skb->nh.raw);
+ memcpy(skb_put(nskb, doffset), skb->data, doffset);
+
+ if (!sg) {
+ nskb->csum = skb_copy_and_csum_bits(skb, offset,
+ skb_put(nskb, len),
+ len, 0);
+ continue;
+ }
+
+ frag = skb_shinfo(nskb)->frags;
+ k = 0;
+
+ nskb->ip_summed = CHECKSUM_HW;
+ nskb->csum = skb->csum;
+ memcpy(skb_put(nskb, hsize), skb->data + offset, hsize);
+
+ while (pos < offset + len) {
+ BUG_ON(i >= nfrags);
+
+ *frag = skb_shinfo(skb)->frags[i];
+ get_page(frag->page);
+ size = frag->size;
+
+ if (pos < offset) {
+ frag->page_offset += offset - pos;
+ frag->size -= offset - pos;
+ }
+
+ k++;
+
+ if (pos + size <= offset + len) {
+ i++;
+ pos += size;
+ } else {
+ frag->size -= pos + size - (offset + len);
+ break;
+ }
+
+ frag++;
+ }
+
+ skb_shinfo(nskb)->nr_frags = k;
+ nskb->data_len = len - hsize;
+ nskb->len += nskb->data_len;
+ nskb->truesize += nskb->data_len;
+ } while ((offset += len) < skb->len);
+
+ return segs;
+
+err:
+ while ((skb = segs)) {
+ segs = skb->next;
+ kfree(skb);
+ }
+ return ERR_PTR(err);
+}
+
+EXPORT_SYMBOL_GPL(skb_segment);
+
void __init skb_init(void)
{
skbuff_head_cache = kmem_cache_create("skbuff_head_cache",
git://git.onelab.eu / linux-2.6.git / blobdiff