net: add skb frag size accessors
[pandora-kernel.git] / drivers / net / xen-netback / netback.c
index fd00f25..d550895 100644 (file)
@@ -60,6 +60,9 @@ struct netbk_rx_meta {
 
 #define MAX_PENDING_REQS 256
 
+/* Discriminate from any valid pending_idx value. */
+#define INVALID_PENDING_IDX 0xFFFF
+
 #define MAX_BUFFER_OFFSET PAGE_SIZE
 
 /* extra field used in struct page */
@@ -155,13 +158,13 @@ static struct xen_netif_rx_response *make_rx_response(struct xenvif *vif,
                                             u16      flags);
 
 static inline unsigned long idx_to_pfn(struct xen_netbk *netbk,
-                                      unsigned int idx)
+                                      u16 idx)
 {
        return page_to_pfn(netbk->mmap_pages[idx]);
 }
 
 static inline unsigned long idx_to_kaddr(struct xen_netbk *netbk,
-                                        unsigned int idx)
+                                        u16 idx)
 {
        return (unsigned long)pfn_to_kaddr(idx_to_pfn(netbk, idx));
 }
@@ -215,6 +218,16 @@ static int get_page_ext(struct page *pg,
                         sizeof(struct iphdr) + MAX_IPOPTLEN + \
                         sizeof(struct tcphdr) + MAX_TCP_OPTION_SPACE)
 
+static u16 frag_get_pending_idx(skb_frag_t *frag)
+{
+       return (u16)frag->page_offset;
+}
+
+static void frag_set_pending_idx(skb_frag_t *frag, u16 pending_idx)
+{
+       frag->page_offset = pending_idx;
+}
+
 static inline pending_ring_idx_t pending_index(unsigned i)
 {
        return i & (MAX_PENDING_REQS-1);
@@ -321,7 +334,7 @@ unsigned int xen_netbk_count_skb_slots(struct xenvif *vif, struct sk_buff *skb)
                count++;
 
        for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
-               unsigned long size = skb_shinfo(skb)->frags[i].size;
+               unsigned long size = skb_frag_size(&skb_shinfo(skb)->frags[i]);
                unsigned long bytes;
                while (size > 0) {
                        BUG_ON(copy_off > MAX_BUFFER_OFFSET);
@@ -512,8 +525,8 @@ static int netbk_gop_skb(struct sk_buff *skb,
 
        for (i = 0; i < nr_frags; i++) {
                netbk_gop_frag_copy(vif, skb, npo,
-                                   skb_shinfo(skb)->frags[i].page,
-                                   skb_shinfo(skb)->frags[i].size,
+                                   skb_frag_page(&skb_shinfo(skb)->frags[i]),
+                                   skb_frag_size(&skb_shinfo(skb)->frags[i]),
                                    skb_shinfo(skb)->frags[i].page_offset,
                                    &head);
        }
@@ -890,7 +903,7 @@ static int netbk_count_requests(struct xenvif *vif,
 
 static struct page *xen_netbk_alloc_page(struct xen_netbk *netbk,
                                         struct sk_buff *skb,
-                                        unsigned long pending_idx)
+                                        u16 pending_idx)
 {
        struct page *page;
        page = alloc_page(GFP_KERNEL|__GFP_COLD);
@@ -909,11 +922,11 @@ static struct gnttab_copy *xen_netbk_get_requests(struct xen_netbk *netbk,
 {
        struct skb_shared_info *shinfo = skb_shinfo(skb);
        skb_frag_t *frags = shinfo->frags;
-       unsigned long pending_idx = *((u16 *)skb->data);
+       u16 pending_idx = *((u16 *)skb->data);
        int i, start;
 
        /* Skip first skb fragment if it is on same page as header fragment. */
-       start = ((unsigned long)shinfo->frags[0].page == pending_idx);
+       start = (frag_get_pending_idx(&shinfo->frags[0]) == pending_idx);
 
        for (i = start; i < shinfo->nr_frags; i++, txp++) {
                struct page *page;
@@ -945,7 +958,7 @@ static struct gnttab_copy *xen_netbk_get_requests(struct xen_netbk *netbk,
                memcpy(&pending_tx_info[pending_idx].req, txp, sizeof(*txp));
                xenvif_get(vif);
                pending_tx_info[pending_idx].vif = vif;
-               frags[i].page = (void *)pending_idx;
+               frag_set_pending_idx(&frags[i], pending_idx);
        }
 
        return gop;
@@ -956,7 +969,7 @@ static int xen_netbk_tx_check_gop(struct xen_netbk *netbk,
                                  struct gnttab_copy **gopp)
 {
        struct gnttab_copy *gop = *gopp;
-       int pending_idx = *((u16 *)skb->data);
+       u16 pending_idx = *((u16 *)skb->data);
        struct pending_tx_info *pending_tx_info = netbk->pending_tx_info;
        struct xenvif *vif = pending_tx_info[pending_idx].vif;
        struct xen_netif_tx_request *txp;
@@ -976,13 +989,13 @@ static int xen_netbk_tx_check_gop(struct xen_netbk *netbk,
        }
 
        /* Skip first skb fragment if it is on same page as header fragment. */
-       start = ((unsigned long)shinfo->frags[0].page == pending_idx);
+       start = (frag_get_pending_idx(&shinfo->frags[0]) == pending_idx);
 
        for (i = start; i < nr_frags; i++) {
                int j, newerr;
                pending_ring_idx_t index;
 
-               pending_idx = (unsigned long)shinfo->frags[i].page;
+               pending_idx = frag_get_pending_idx(&shinfo->frags[i]);
 
                /* Check error status: if okay then remember grant handle. */
                newerr = (++gop)->status;
@@ -1008,7 +1021,7 @@ static int xen_netbk_tx_check_gop(struct xen_netbk *netbk,
                pending_idx = *((u16 *)skb->data);
                xen_netbk_idx_release(netbk, pending_idx);
                for (j = start; j < i; j++) {
-                       pending_idx = (unsigned long)shinfo->frags[i].page;
+                       pending_idx = frag_get_pending_idx(&shinfo->frags[i]);
                        xen_netbk_idx_release(netbk, pending_idx);
                }
 
@@ -1029,15 +1042,14 @@ static void xen_netbk_fill_frags(struct xen_netbk *netbk, struct sk_buff *skb)
        for (i = 0; i < nr_frags; i++) {
                skb_frag_t *frag = shinfo->frags + i;
                struct xen_netif_tx_request *txp;
-               unsigned long pending_idx;
+               struct page *page;
+               u16 pending_idx;
 
-               pending_idx = (unsigned long)frag->page;
+               pending_idx = frag_get_pending_idx(frag);
 
                txp = &netbk->pending_tx_info[pending_idx].req;
-               frag->page = virt_to_page(idx_to_kaddr(netbk, pending_idx));
-               frag->size = txp->size;
-               frag->page_offset = txp->offset;
-
+               page = virt_to_page(idx_to_kaddr(netbk, pending_idx));
+               __skb_fill_page_desc(skb, i, page, txp->offset, txp->size);
                skb->len += txp->size;
                skb->data_len += txp->size;
                skb->truesize += txp->size;
@@ -1349,11 +1361,11 @@ static unsigned xen_netbk_tx_build_gops(struct xen_netbk *netbk)
                skb_shinfo(skb)->nr_frags = ret;
                if (data_len < txreq.size) {
                        skb_shinfo(skb)->nr_frags++;
-                       skb_shinfo(skb)->frags[0].page =
-                               (void *)(unsigned long)pending_idx;
+                       frag_set_pending_idx(&skb_shinfo(skb)->frags[0],
+                                            pending_idx);
                } else {
-                       /* Discriminate from any valid pending_idx value. */
-                       skb_shinfo(skb)->frags[0].page = (void *)~0UL;
+                       frag_set_pending_idx(&skb_shinfo(skb)->frags[0],
+                                            INVALID_PENDING_IDX);
                }
 
                __skb_queue_tail(&netbk->tx_queue, skb);