1 files changed, 48 insertions, 25 deletions

diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index c0a4f3ab0cc0..a24218c9c84b 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -187,6 +187,20 @@ enum {
 
         /* ensure the originating sk reference is available on driver level */
         SKBTX_DRV_NEEDS_SK_REF = 1 << 3,
+
+        /* device driver supports TX zero-copy buffers */
+        SKBTX_DEV_ZEROCOPY = 1 << 4,
+};
+
+/*
+ * The callback notifies userspace to release buffers when skb DMA is done in
+ * lower device, the skb last reference should be 0 when calling this.
+ * The desc is used to track userspace buffer index.
+ */
+struct ubuf_info {
+        void (*callback)(void *);
+        void *arg;
+        unsigned long desc;
 };
 
 /* This data is invariant across clones and lives at
@@ -211,6 +225,7 @@ struct skb_shared_info {
         /* Intermediate layers must ensure that destructor_arg
          * remains valid until skb destructor */
         void *          destructor_arg;
+
         /* must be last field, see pskb_expand_head() */
         skb_frag_t      frags[MAX_SKB_FRAGS];
 };
@@ -270,15 +285,12 @@ typedef unsigned char *sk_buff_data_t;
  *      struct sk_buff - socket buffer
  *      @next: Next buffer in list
  *      @prev: Previous buffer in list
- *      @sk: Socket we are owned by
  *      @tstamp: Time we arrived
+ *      @sk: Socket we are owned by
  *      @dev: Device we arrived on/are leaving by
- *      @transport_header: Transport layer header
- *      @network_header: Network layer header
- *      @mac_header: Link layer header
+ *      @cb: Control buffer. Free for use by every layer. Put private vars here
  *      @_skb_refdst: destination entry (with norefcount bit)
  *      @sp: the security path, used for xfrm
- *      @cb: Control buffer. Free for use by every layer. Put private vars here
  *      @len: Length of actual data
  *      @data_len: Data length
  *      @mac_len: Length of link layer header
@@ -286,40 +298,45 @@ typedef unsigned char *sk_buff_data_t;
  *      @csum: Checksum (must include start/offset pair)
  *      @csum_start: Offset from skb->head where checksumming should start
  *      @csum_offset: Offset from csum_start where checksum should be stored
+ *      @priority: Packet queueing priority
  *      @local_df: allow local fragmentation
  *      @cloned: Head may be cloned (check refcnt to be sure)
+ *      @ip_summed: Driver fed us an IP checksum
  *      @nohdr: Payload reference only, must not modify header
+ *      @nfctinfo: Relationship of this skb to the connection
  *      @pkt_type: Packet class
  *      @fclone: skbuff clone status
- *      @ip_summed: Driver fed us an IP checksum
- *      @priority: Packet queueing priority
- *      @users: User count - see {datagram,tcp}.c
- *      @protocol: Packet protocol from driver
- *      @truesize: Buffer size 
- *      @head: Head of buffer
- *      @data: Data head pointer
- *      @tail: Tail pointer
- *      @end: End pointer
- *      @destructor: Destruct function
- *      @mark: Generic packet mark
- *      @nfct: Associated connection, if any
  *      @ipvs_property: skbuff is owned by ipvs
  *      @peeked: this packet has been seen already, so stats have been
  *              done for it, don't do them again
  *      @nf_trace: netfilter packet trace flag
- *      @nfctinfo: Relationship of this skb to the connection
+ *      @protocol: Packet protocol from driver
+ *      @destructor: Destruct function
+ *      @nfct: Associated connection, if any
  *      @nfct_reasm: netfilter conntrack re-assembly pointer
  *      @nf_bridge: Saved data about a bridged frame - see br_netfilter.c
  *      @skb_iif: ifindex of device we arrived on
- *      @rxhash: the packet hash computed on receive
- *      @queue_mapping: Queue mapping for multiqueue devices
  *      @tc_index: Traffic control index
  *      @tc_verd: traffic control verdict
+ *      @rxhash: the packet hash computed on receive
+ *      @queue_mapping: Queue mapping for multiqueue devices
  *      @ndisc_nodetype: router type (from link layer)
+ *      @ooo_okay: allow the mapping of a socket to a queue to be changed
  *      @dma_cookie: a cookie to one of several possible DMA operations
  *              done by skb DMA functions
  *      @secmark: security marking
+ *      @mark: Generic packet mark
+ *      @dropcount: total number of sk_receive_queue overflows
  *      @vlan_tci: vlan tag control information
+ *      @transport_header: Transport layer header
+ *      @network_header: Network layer header
+ *      @mac_header: Link layer header
+ *      @tail: Tail pointer
+ *      @end: End pointer
+ *      @head: Head of buffer
+ *      @data: Data head pointer
+ *      @truesize: Buffer size
+ *      @users: User count - see {datagram,tcp}.c
  */
 
 struct sk_buff {
@@ -1562,16 +1579,22 @@ static inline struct sk_buff *netdev_alloc_skb(struct net_device *dev,
         return __netdev_alloc_skb(dev, length, GFP_ATOMIC);
 }
 
-static inline struct sk_buff *netdev_alloc_skb_ip_align(struct net_device *dev,
-                unsigned int length)
+static inline struct sk_buff *__netdev_alloc_skb_ip_align(struct net_device *dev,
+                unsigned int length, gfp_t gfp)
 {
-        struct sk_buff *skb = netdev_alloc_skb(dev, length + NET_IP_ALIGN);
+        struct sk_buff *skb = __netdev_alloc_skb(dev, length + NET_IP_ALIGN, gfp);
 
         if (NET_IP_ALIGN && skb)
                 skb_reserve(skb, NET_IP_ALIGN);
         return skb;
 }
 
+static inline struct sk_buff *netdev_alloc_skb_ip_align(struct net_device *dev,
+                unsigned int length)
+{
+        return __netdev_alloc_skb_ip_align(dev, length, GFP_ATOMIC);
+}
+
 /**
  *      __netdev_alloc_page - allocate a page for ps-rx on a specific device
  *      @dev: network device to receive on
@@ -2028,8 +2051,7 @@ static inline void sw_tx_timestamp(struct sk_buff *skb)
  * skb_tx_timestamp() - Driver hook for transmit timestamping
  *
  * Ethernet MAC Drivers should call this function in their hard_xmit()
- * function as soon as possible after giving the sk_buff to the MAC
- * hardware, but before freeing the sk_buff.
+ * function immediately before giving the sk_buff to the MAC hardware.
  *
  * @skb: A socket buffer.
  */
@@ -2266,5 +2288,6 @@ static inline void skb_checksum_none_assert(struct sk_buff *skb)
 }
 
 bool skb_partial_csum_set(struct sk_buff *skb, u16 start, u16 off);
+
 #endif  /* __KERNEL__ */
 #endif  /* _LINUX_SKBUFF_H */