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 diff --git a/include/net/xdp.h b/include/net/xdp.h
  26 index 8f0812e4996d..485e9495a690 100644
  27 --- a/include/net/xdp.h
  28 +++ b/include/net/xdp.h
  29 @@ -66,6 +66,10 @@ struct xdp_txq_info {
  30         struct net_device *dev;
  31  };
  32
  33 +enum xdp_buff_flags {
  34 +       XDP_FLAGS_HAS_FRAGS     = BIT(0), /* non-linear xdp buff */
  35 +};
  36 +
  37  struct xdp_buff {
  38         void *data;
  39         void *data_end;
  40 @@ -74,13 +78,30 @@ struct xdp_buff {
  41         struct xdp_rxq_info *rxq;
  42         struct xdp_txq_info *txq;
  43         u32 frame_sz; /* frame size to deduce data_hard_end/reserved tailroom*/
  44 +       u32 flags; /* supported values defined in xdp_buff_flags */
  45  };
  46
  47 +static __always_inline bool xdp_buff_has_frags(struct xdp_buff *xdp)
  48 +{
  49 +       return !!(xdp->flags & XDP_FLAGS_HAS_FRAGS);
  50 +}
  51 +
  52 +static __always_inline void xdp_buff_set_frags_flag(struct xdp_buff *xdp)
  53 +{
  54 +       xdp->flags |= XDP_FLAGS_HAS_FRAGS;
  55 +}
  56 +
  57 +static __always_inline void xdp_buff_clear_frags_flag(struct xdp_buff *xdp)
  58 +{
  59 +       xdp->flags &= ~XDP_FLAGS_HAS_FRAGS;
  60 +}
  61 +
  62  static __always_inline void
  63  xdp_init_buff(struct xdp_buff *xdp, u32 frame_sz, struct xdp_rxq_info *rxq)
  64  {
  65         xdp->frame_sz = frame_sz;
  66         xdp->rxq = rxq;
  67 +       xdp->flags = 0;
  68  }
  69
  70  static __always_inline void
  71 @@ -122,8 +143,14 @@ struct xdp_frame {
  72          */
  73         struct xdp_mem_info mem;
  74         struct net_device *dev_rx; /* used by cpumap */
  75 +       u32 flags; /* supported values defined in xdp_buff_flags */
  76  };
  77
  78 +static __always_inline bool xdp_frame_has_frags(struct xdp_frame *frame)
  79 +{
  80 +       return !!(frame->flags & XDP_FLAGS_HAS_FRAGS);
  81 +}
  82 +
  83  #define XDP_BULK_QUEUE_SIZE    16
  84  struct xdp_frame_bulk {
  85         int count;
  86 @@ -180,6 +207,7 @@ void xdp_convert_frame_to_buff(struct xd
  87         xdp->data_end = frame->data + frame->len;
  88         xdp->data_meta = frame->data - frame->metasize;
  89         xdp->frame_sz = frame->frame_sz;
  90 +       xdp->flags = frame->flags;
  91  }
  92
  93  static inline
  94 @@ -206,6 +234,7 @@ int xdp_update_frame_from_buff(struct xd
  95         xdp_frame->headroom = headroom - sizeof(*xdp_frame);
  96         xdp_frame->metasize = metasize;
  97         xdp_frame->frame_sz = xdp->frame_sz;
  98 +       xdp_frame->flags = xdp->flags;
  99
 100         return 0;
 101  }