target/linux/generic/backport-5.15/605-v5.18-xdp-introduce-flags-field-in-xdp_buff-xdp_frame.patch

   1 From 2e88d4ff03013937028f5397268b21e10cf68713 Mon Sep 17 00:00:00 2001
   2 From: Lorenzo Bianconi <lorenzo@kernel.org>
   3 Date: Fri, 21 Jan 2022 11:09:45 +0100
   4 Subject: [PATCH] xdp: introduce flags field in xdp_buff/xdp_frame
   5
   6 Introduce flags field in xdp_frame and xdp_buffer data structures
   7 to define additional buffer features. At the moment the only
   8 supported buffer feature is frags bit (XDP_FLAGS_HAS_FRAGS).
   9 frags bit is used to specify if this is a linear buffer
  10 (XDP_FLAGS_HAS_FRAGS not set) or a frags frame (XDP_FLAGS_HAS_FRAGS
  11 set). In the latter case the driver is expected to initialize the
  12 skb_shared_info structure at the end of the first buffer to link together
  13 subsequent buffers belonging to the same frame.
  14
  15 Acked-by: Toke Hoiland-Jorgensen <toke@redhat.com>
  16 Acked-by: John Fastabend <john.fastabend@gmail.com>
  17 Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
  18 Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
  19 Link: https://lore.kernel.org/r/e389f14f3a162c0a5bc6a2e1aa8dd01a90be117d.1642758637.git.lorenzo@kernel.org
  20 Signed-off-by: Alexei Starovoitov <ast@kernel.org>
  21 ---
  22  include/net/xdp.h | 29 +++++++++++++++++++++++++++++
  23  1 file changed, 29 insertions(+)
  24
  25 --- a/include/net/xdp.h
  26 +++ b/include/net/xdp.h
  27 @@ -66,6 +66,10 @@ struct xdp_txq_info {
  28         struct net_device *dev;
  29  };
  30
  31 +enum xdp_buff_flags {
  32 +       XDP_FLAGS_HAS_FRAGS     = BIT(0), /* non-linear xdp buff */
  33 +};
  34 +
  35  struct xdp_buff {
  36         void *data;
  37         void *data_end;
  38 @@ -74,13 +78,30 @@ struct xdp_buff {
  39         struct xdp_rxq_info *rxq;
  40         struct xdp_txq_info *txq;
  41         u32 frame_sz; /* frame size to deduce data_hard_end/reserved tailroom*/
  42 +       u32 flags; /* supported values defined in xdp_buff_flags */
  43  };
  44
  45 +static __always_inline bool xdp_buff_has_frags(struct xdp_buff *xdp)
  46 +{
  47 +       return !!(xdp->flags & XDP_FLAGS_HAS_FRAGS);
  48 +}
  49 +
  50 +static __always_inline void xdp_buff_set_frags_flag(struct xdp_buff *xdp)
  51 +{
  52 +       xdp->flags |= XDP_FLAGS_HAS_FRAGS;
  53 +}
  54 +
  55 +static __always_inline void xdp_buff_clear_frags_flag(struct xdp_buff *xdp)
  56 +{
  57 +       xdp->flags &= ~XDP_FLAGS_HAS_FRAGS;
  58 +}
  59 +
  60  static __always_inline void
  61  xdp_init_buff(struct xdp_buff *xdp, u32 frame_sz, struct xdp_rxq_info *rxq)
  62  {
  63         xdp->frame_sz = frame_sz;
  64         xdp->rxq = rxq;
  65 +       xdp->flags = 0;
  66  }
  67
  68  static __always_inline void
  69 @@ -122,8 +143,14 @@ struct xdp_frame {
  70          */
  71         struct xdp_mem_info mem;
  72         struct net_device *dev_rx; /* used by cpumap */
  73 +       u32 flags; /* supported values defined in xdp_buff_flags */
  74  };
  75
  76 +static __always_inline bool xdp_frame_has_frags(struct xdp_frame *frame)
  77 +{
  78 +       return !!(frame->flags & XDP_FLAGS_HAS_FRAGS);
  79 +}
  80 +
  81  #define XDP_BULK_QUEUE_SIZE    16
  82  struct xdp_frame_bulk {
  83         int count;
  84 @@ -180,6 +207,7 @@ void xdp_convert_frame_to_buff(struct xd
  85         xdp->data_end = frame->data + frame->len;
  86         xdp->data_meta = frame->data - frame->metasize;
  87         xdp->frame_sz = frame->frame_sz;
  88 +       xdp->flags = frame->flags;
  89  }
  90
  91  static inline
  92 @@ -206,6 +234,7 @@ int xdp_update_frame_from_buff(struct xd
  93         xdp_frame->headroom = headroom - sizeof(*xdp_frame);
  94         xdp_frame->metasize = metasize;
  95         xdp_frame->frame_sz = xdp->frame_sz;
  96 +       xdp_frame->flags = xdp->flags;
  97
  98         return 0;
  99  }