]> git.karo-electronics.de Git - karo-tx-linux.git/blobdiff - net/core/skbuff.c
[NET]: Assign skb->dev in netdev_alloc_skb
[karo-tx-linux.git] / net / core / skbuff.c
index bb7210f4005e1a781908238d0bfbbb30a42838a1..c54f3664bce5b0e868928df71c392dc18f89f2a0 100644 (file)
@@ -38,7 +38,6 @@
  *     The functions in this file will not compile correctly with gcc 2.4.x
  */
 
-#include <linux/config.h>
 #include <linux/module.h>
 #include <linux/types.h>
 #include <linux/kernel.h>
@@ -172,9 +171,9 @@ struct sk_buff *__alloc_skb(unsigned int size, gfp_t gfp_mask,
        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;
 
@@ -238,8 +237,9 @@ struct sk_buff *alloc_skb_from_cache(kmem_cache_t *cp,
 
        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)->gso_size = 0;
+       skb_shinfo(skb)->gso_segs = 0;
+       skb_shinfo(skb)->gso_type = 0;
        skb_shinfo(skb)->frag_list = NULL;
 out:
        return skb;
@@ -249,12 +249,37 @@ nodata:
        goto out;
 }
 
+/**
+ *     __netdev_alloc_skb - allocate an skbuff for rx on a specific device
+ *     @dev: network device to receive on
+ *     @length: length to allocate
+ *     @gfp_mask: get_free_pages mask, passed to alloc_skb
+ *
+ *     Allocate a new &sk_buff and assign it a usage count of one. The
+ *     buffer has unspecified headroom built in. Users should allocate
+ *     the headroom they think they need without accounting for the
+ *     built in space. The built in space is used for optimisations.
+ *
+ *     %NULL is returned if there is no free memory.
+ */
+struct sk_buff *__netdev_alloc_skb(struct net_device *dev,
+               unsigned int length, gfp_t gfp_mask)
+{
+       struct sk_buff *skb;
 
-static void skb_drop_fraglist(struct sk_buff *skb)
+       skb = alloc_skb(length + NET_SKB_PAD, gfp_mask);
+       if (likely(skb)) {
+               skb_reserve(skb, NET_SKB_PAD);
+               skb->dev = dev;
+       }
+       return 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;
@@ -263,6 +288,11 @@ static void skb_drop_fraglist(struct sk_buff *skb)
        } 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;
@@ -271,7 +301,7 @@ static void skb_clone_fraglist(struct sk_buff *skb)
                skb_get(list);
 }
 
-void skb_release_data(struct sk_buff *skb)
+static void skb_release_data(struct sk_buff *skb)
 {
        if (!skb->cloned ||
            !atomic_sub_return(skb->nohdr ? (1 << SKB_DATAREF_SHIFT) + 1 : 1,
@@ -528,8 +558,9 @@ static void copy_skb_header(struct sk_buff *new, const struct sk_buff *old)
 #endif
        skb_copy_secmark(new, old);
        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;
 }
 
 /**
@@ -781,24 +812,40 @@ struct sk_buff *skb_copy_expand(const struct sk_buff *skb,
  *     filled. Used by network drivers which may DMA or transfer data
  *     beyond the buffer end onto the wire.
  *
- *     May return NULL in out of memory cases.
+ *     May return error in out of memory cases. The skb is freed on error.
  */
  
-struct sk_buff *skb_pad(struct sk_buff *skb, int pad)
+int skb_pad(struct sk_buff *skb, int pad)
 {
-       struct sk_buff *nskb;
+       int err;
+       int ntail;
        
        /* If the skbuff is non linear tailroom is always zero.. */
-       if (skb_tailroom(skb) >= pad) {
+       if (!skb_cloned(skb) && skb_tailroom(skb) >= pad) {
                memset(skb->data+skb->len, 0, pad);
-               return skb;
+               return 0;
        }
-       
-       nskb = skb_copy_expand(skb, skb_headroom(skb), skb_tailroom(skb) + pad, GFP_ATOMIC);
+
+       ntail = skb->data_len + pad - (skb->end - skb->tail);
+       if (likely(skb_cloned(skb) || ntail > 0)) {
+               err = pskb_expand_head(skb, 0, ntail, GFP_ATOMIC);
+               if (unlikely(err))
+                       goto free_skb;
+       }
+
+       /* FIXME: The use of this function with non-linear skb's really needs
+        * to be audited.
+        */
+       err = skb_linearize(skb);
+       if (unlikely(err))
+               goto free_skb;
+
+       memset(skb->data + skb->len, 0, pad);
+       return 0;
+
+free_skb:
        kfree_skb(skb);
-       if (nskb)
-               memset(nskb->data+nskb->len, 0, pad);
-       return nskb;
+       return err;
 }      
  
 /* Trims skb to length len. It can change skb pointers.
@@ -806,41 +853,81 @@ struct sk_buff *skb_pad(struct sk_buff *skb, int pad)
 
 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)) {
-                               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;
@@ -1721,12 +1808,15 @@ unsigned int skb_find_text(struct sk_buff *skb, unsigned int from,
                           unsigned int to, struct ts_config *config,
                           struct ts_state *state)
 {
+       unsigned int ret;
+
        config->get_next_block = skb_ts_get_next_block;
        config->finish = skb_ts_finish;
 
        skb_prepare_seq_read(skb, from, to, TS_SKB_CB(state));
 
-       return textsearch_find(config, state);
+       ret = textsearch_find(config, state);
+       return (ret <= to - from ? ret : UINT_MAX);
 }
 
 /**
@@ -1824,6 +1914,133 @@ unsigned char *skb_pull_rcsum(struct sk_buff *skb, unsigned int len)
 
 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",
@@ -1849,6 +2066,7 @@ EXPORT_SYMBOL(__kfree_skb);
 EXPORT_SYMBOL(kfree_skb);
 EXPORT_SYMBOL(__pskb_pull_tail);
 EXPORT_SYMBOL(__alloc_skb);
+EXPORT_SYMBOL(__netdev_alloc_skb);
 EXPORT_SYMBOL(pskb_copy);
 EXPORT_SYMBOL(pskb_expand_head);
 EXPORT_SYMBOL(skb_checksum);