sfc: Cleaned up struct tso_state fields

Squashed nested structures.

Renamed remaining_len to out_len, ifc.len to in_len, header_length to
header_len.

Moved ipv4_id into the group of output variables where it belongs.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

diff --git a/drivers/net/sfc/tx.c b/drivers/net/sfc/tx.c
index 51429b6a4deed14fa187887583a3a0022380ec1a..550856fab16c26e0fa53552179fd690785067e05 100644 (file)
--- a/drivers/net/sfc/tx.c
+++ b/drivers/net/sfc/tx.c
@@ -540,46 +540,37 @@ void efx_remove_tx_queue(struct efx_tx_queue *tx_queue)
 
 /**
  * struct tso_state - TSO state for an SKB
- * @remaining_len: Bytes of data we've yet to segment
+ * @out_len: Remaining length in current segment
  * @seqnum: Current sequence number
+ * @ipv4_id: Current IPv4 ID, host endian
  * @packet_space: Remaining space in current packet
- * @ifc: Input fragment cursor.
- *     Where we are in the current fragment of the incoming SKB.  These
- *     values get updated in place when we split a fragment over
- *     multiple packets.
- * @p: Parameters.
- *     These values are set once at the start of the TSO send and do
- *     not get changed as the routine progresses.
+ * @dma_addr: DMA address of current position
+ * @in_len: Remaining length in current SKB fragment
+ * @unmap_len: Length of SKB fragment
+ * @unmap_addr: DMA address of SKB fragment
+ * @unmap_single: DMA single vs page mapping flag
+ * @header_len: Number of bytes of header
+ * @full_packet_size: Number of bytes to put in each outgoing segment
  *
  * The state used during segmentation.  It is put into this data structure
  * just to make it easy to pass into inline functions.
  */
 struct tso_state {
-       unsigned remaining_len;
+       /* Output position */
+       unsigned out_len;
        unsigned seqnum;
+       unsigned ipv4_id;
        unsigned packet_space;
 
-       struct {
-               /* DMA address of current position */
-               dma_addr_t dma_addr;
-               /* Remaining length */
-               unsigned int len;
-               /* DMA address and length of the whole fragment */
-               unsigned int unmap_len;
-               dma_addr_t unmap_addr;
-               bool unmap_single;
-       } ifc;
-
-       struct {
-               /* The number of bytes of header */
-               unsigned int header_length;
-
-               /* The number of bytes to put in each outgoing segment. */
-               int full_packet_size;
-
-               /* Current IPv4 ID, host endian. */
-               unsigned ipv4_id;
-       } p;
+       /* Input position */
+       dma_addr_t dma_addr;
+       unsigned in_len;
+       unsigned unmap_len;
+       dma_addr_t unmap_addr;
+       bool unmap_single;
+
+       unsigned header_len;
+       int full_packet_size;
 };
 
 
@@ -840,35 +831,34 @@ static inline void tso_start(struct tso_state *st, const struct sk_buff *skb)
        /* All ethernet/IP/TCP headers combined size is TCP header size
         * plus offset of TCP header relative to start of packet.
         */
-       st->p.header_length = ((tcp_hdr(skb)->doff << 2u)
-                              + PTR_DIFF(tcp_hdr(skb), skb->data));
-       st->p.full_packet_size = (st->p.header_length
-                                 + skb_shinfo(skb)->gso_size);
+       st->header_len = ((tcp_hdr(skb)->doff << 2u)
+                         + PTR_DIFF(tcp_hdr(skb), skb->data));
+       st->full_packet_size = st->header_len + skb_shinfo(skb)->gso_size;
 
-       st->p.ipv4_id = ntohs(ip_hdr(skb)->id);
+       st->ipv4_id = ntohs(ip_hdr(skb)->id);
        st->seqnum = ntohl(tcp_hdr(skb)->seq);
 
        EFX_BUG_ON_PARANOID(tcp_hdr(skb)->urg);
        EFX_BUG_ON_PARANOID(tcp_hdr(skb)->syn);
        EFX_BUG_ON_PARANOID(tcp_hdr(skb)->rst);
 
-       st->packet_space = st->p.full_packet_size;
-       st->remaining_len = skb->len - st->p.header_length;
-       st->ifc.unmap_len = 0;
-       st->ifc.unmap_single = false;
+       st->packet_space = st->full_packet_size;
+       st->out_len = skb->len - st->header_len;
+       st->unmap_len = 0;
+       st->unmap_single = false;
 }
 
 static inline int tso_get_fragment(struct tso_state *st, struct efx_nic *efx,
                                   skb_frag_t *frag)
 {
-       st->ifc.unmap_addr = pci_map_page(efx->pci_dev, frag->page,
-                                         frag->page_offset, frag->size,
-                                         PCI_DMA_TODEVICE);
-       if (likely(!pci_dma_mapping_error(efx->pci_dev, st->ifc.unmap_addr))) {
-               st->ifc.unmap_single = false;
-               st->ifc.unmap_len = frag->size;
-               st->ifc.len = frag->size;
-               st->ifc.dma_addr = st->ifc.unmap_addr;
+       st->unmap_addr = pci_map_page(efx->pci_dev, frag->page,
+                                     frag->page_offset, frag->size,
+                                     PCI_DMA_TODEVICE);
+       if (likely(!pci_dma_mapping_error(efx->pci_dev, st->unmap_addr))) {
+               st->unmap_single = false;
+               st->unmap_len = frag->size;
+               st->in_len = frag->size;
+               st->dma_addr = st->unmap_addr;
                return 0;
        }
        return -ENOMEM;
@@ -878,16 +868,16 @@ static inline int
 tso_get_head_fragment(struct tso_state *st, struct efx_nic *efx,
                      const struct sk_buff *skb)
 {
-       int hl = st->p.header_length;
+       int hl = st->header_len;
        int len = skb_headlen(skb) - hl;
 
-       st->ifc.unmap_addr = pci_map_single(efx->pci_dev, skb->data + hl,
-                                           len, PCI_DMA_TODEVICE);
-       if (likely(!pci_dma_mapping_error(efx->pci_dev, st->ifc.unmap_addr))) {
-               st->ifc.unmap_single = true;
-               st->ifc.unmap_len = len;
-               st->ifc.len = len;
-               st->ifc.dma_addr = st->ifc.unmap_addr;
+       st->unmap_addr = pci_map_single(efx->pci_dev, skb->data + hl,
+                                       len, PCI_DMA_TODEVICE);
+       if (likely(!pci_dma_mapping_error(efx->pci_dev, st->unmap_addr))) {
+               st->unmap_single = true;
+               st->unmap_len = len;
+               st->in_len = len;
+               st->dma_addr = st->unmap_addr;
                return 0;
        }
        return -ENOMEM;
@@ -911,38 +901,38 @@ static inline int tso_fill_packet_with_fragment(struct efx_tx_queue *tx_queue,
        struct efx_tx_buffer *buffer;
        int n, end_of_packet, rc;
 
-       if (st->ifc.len == 0)
+       if (st->in_len == 0)
                return 0;
        if (st->packet_space == 0)
                return 0;
 
-       EFX_BUG_ON_PARANOID(st->ifc.len <= 0);
+       EFX_BUG_ON_PARANOID(st->in_len <= 0);
        EFX_BUG_ON_PARANOID(st->packet_space <= 0);
 
-       n = min(st->ifc.len, st->packet_space);
+       n = min(st->in_len, st->packet_space);
 
        st->packet_space -= n;
-       st->remaining_len -= n;
-       st->ifc.len -= n;
+       st->out_len -= n;
+       st->in_len -= n;
 
-       rc = efx_tx_queue_insert(tx_queue, st->ifc.dma_addr, n, &buffer);
+       rc = efx_tx_queue_insert(tx_queue, st->dma_addr, n, &buffer);
        if (likely(rc == 0)) {
-               if (st->remaining_len == 0)
+               if (st->out_len == 0)
                        /* Transfer ownership of the skb */
                        buffer->skb = skb;
 
-               end_of_packet = st->remaining_len == 0 || st->packet_space == 0;
+               end_of_packet = st->out_len == 0 || st->packet_space == 0;
                buffer->continuation = !end_of_packet;
 
-               if (st->ifc.len == 0) {
+               if (st->in_len == 0) {
                        /* Transfer ownership of the pci mapping */
-                       buffer->unmap_len = st->ifc.unmap_len;
-                       buffer->unmap_single = st->ifc.unmap_single;
-                       st->ifc.unmap_len = 0;
+                       buffer->unmap_len = st->unmap_len;
+                       buffer->unmap_single = st->unmap_single;
+                       st->unmap_len = 0;
                }
        }
 
-       st->ifc.dma_addr += n;
+       st->dma_addr += n;
        return rc;
 }
 
@@ -967,7 +957,7 @@ static inline int tso_start_new_packet(struct efx_tx_queue *tx_queue,
        u8 *header;
 
        /* Allocate a DMA-mapped header buffer. */
-       if (likely(TSOH_SIZE(st->p.header_length) <= TSOH_STD_SIZE)) {
+       if (likely(TSOH_SIZE(st->header_len) <= TSOH_STD_SIZE)) {
                if (tx_queue->tso_headers_free == NULL) {
                        if (efx_tsoh_block_alloc(tx_queue))
                                return -1;
@@ -978,7 +968,7 @@ static inline int tso_start_new_packet(struct efx_tx_queue *tx_queue,
                tsoh->unmap_len = 0;
        } else {
                tx_queue->tso_long_headers++;
-               tsoh = efx_tsoh_heap_alloc(tx_queue, st->p.header_length);
+               tsoh = efx_tsoh_heap_alloc(tx_queue, st->header_len);
                if (unlikely(!tsoh))
                        return -1;
        }
@@ -988,33 +978,32 @@ static inline int tso_start_new_packet(struct efx_tx_queue *tx_queue,
        tsoh_iph = (struct iphdr *)(header + SKB_IPV4_OFF(skb));
 
        /* Copy and update the headers. */
-       memcpy(header, skb->data, st->p.header_length);
+       memcpy(header, skb->data, st->header_len);
 
        tsoh_th->seq = htonl(st->seqnum);
        st->seqnum += skb_shinfo(skb)->gso_size;
-       if (st->remaining_len > skb_shinfo(skb)->gso_size) {
+       if (st->out_len > skb_shinfo(skb)->gso_size) {
                /* This packet will not finish the TSO burst. */
-               ip_length = st->p.full_packet_size - ETH_HDR_LEN(skb);
+               ip_length = st->full_packet_size - ETH_HDR_LEN(skb);
                tsoh_th->fin = 0;
                tsoh_th->psh = 0;
        } else {
                /* This packet will be the last in the TSO burst. */
-               ip_length = (st->p.header_length - ETH_HDR_LEN(skb)
-                            + st->remaining_len);
+               ip_length = st->header_len - ETH_HDR_LEN(skb) + st->out_len;
                tsoh_th->fin = tcp_hdr(skb)->fin;
                tsoh_th->psh = tcp_hdr(skb)->psh;
        }
        tsoh_iph->tot_len = htons(ip_length);
 
        /* Linux leaves suitable gaps in the IP ID space for us to fill. */
-       tsoh_iph->id = htons(st->p.ipv4_id);
-       st->p.ipv4_id++;
+       tsoh_iph->id = htons(st->ipv4_id);
+       st->ipv4_id++;
 
        st->packet_space = skb_shinfo(skb)->gso_size;
        ++tx_queue->tso_packets;
 
        /* Form a descriptor for this header. */
-       efx_tso_put_header(tx_queue, tsoh, st->p.header_length);
+       efx_tso_put_header(tx_queue, tsoh, st->header_len);
 
        return 0;
 }
@@ -1048,7 +1037,7 @@ static int efx_enqueue_skb_tso(struct efx_tx_queue *tx_queue,
        /* Assume that skb header area contains exactly the headers, and
         * all payload is in the frag list.
         */
-       if (skb_headlen(skb) == state.p.header_length) {
+       if (skb_headlen(skb) == state.header_len) {
                /* Grab the first payload fragment. */
                EFX_BUG_ON_PARANOID(skb_shinfo(skb)->nr_frags < 1);
                frag_i = 0;
@@ -1072,7 +1061,7 @@ static int efx_enqueue_skb_tso(struct efx_tx_queue *tx_queue,
                        goto stop;
 
                /* Move onto the next fragment? */
-               if (state.ifc.len == 0) {
+               if (state.in_len == 0) {
                        if (++frag_i >= skb_shinfo(skb)->nr_frags)
                                /* End of payload reached. */
                                break;
@@ -1108,13 +1097,13 @@ static int efx_enqueue_skb_tso(struct efx_tx_queue *tx_queue,
 
  unwind:
        /* Free the DMA mapping we were in the process of writing out */
-       if (state.ifc.unmap_len) {
-               if (state.ifc.unmap_single)
-                       pci_unmap_single(efx->pci_dev, state.ifc.unmap_addr,
-                                        state.ifc.unmap_len, PCI_DMA_TODEVICE);
+       if (state.unmap_len) {
+               if (state.unmap_single)
+                       pci_unmap_single(efx->pci_dev, state.unmap_addr,
+                                        state.unmap_len, PCI_DMA_TODEVICE);
                else
-                       pci_unmap_page(efx->pci_dev, state.ifc.unmap_addr,
-                                      state.ifc.unmap_len, PCI_DMA_TODEVICE);
+                       pci_unmap_page(efx->pci_dev, state.unmap_addr,
+                                      state.unmap_len, PCI_DMA_TODEVICE);
        }
 
        efx_enqueue_unwind(tx_queue);