Merge branch 'XDP-redirect-memory-return-API'

Jesper Dangaard Brouer says:

====================
XDP redirect memory return API

Submitted against net-next, as it contains NIC driver changes.

This patchset works towards supporting different XDP RX-ring memory
allocators.  As this will be needed by the AF_XDP zero-copy mode.

The patchset uses mlx5 as the sample driver, which gets implemented
XDP_REDIRECT RX-mode, but not ndo_xdp_xmit (as this API is subject to
change thought the patchset).

A new struct xdp_frame is introduced (modeled after cpumap xdp_pkt).
And both ndo_xdp_xmit and the new xdp_return_frame end-up using this.

Support for a driver supplied allocator is implemented, and a
refurbished version of page_pool is the first return allocator type
introduced.  This will be a integration point for AF_XDP zero-copy.

The mlx5 driver evolve into using the page_pool, and see a performance
increase (with ndo_xdp_xmit out ixgbe driver) from 6Mpps to 12Mpps.

The patchset stop at 16 patches (one over limit), but more API changes
are planned.  Specifically extending ndo_xdp_xmit and xdp_return_frame
APIs to support bulking.  As this will address some known limits.

V2: Updated according to Tariq's feedback
V3: Updated based on feedback from Jason Wang and Alex Duyck
V4: Updated based on feedback from Tariq and Jason
V5: Fix SPDX license, add Tariq's reviews, improve patch desc for perf test
V6: Updated based on feedback from Eric Dumazet and Alex Duyck
V7: Adapt to i40e that got XDP_REDIRECT support in-between
V8:
 Updated based on feedback kbuild test robot, and adjust for mlx5 changes
 page_pool only compiled into kernel when drivers Kconfig 'select' feature
V9:
 Remove some inline statements, let compiler decide what to inline
 Fix return value in virtio_net driver
 Adjust for mlx5 changes in-between submissions
V10:
 Minor adjust for mlx5 requested by Tariq
 Resubmit against net-next
V11: avoid leaking info stored in frame data on page reuse
====================

Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 5 insertions, 27 deletions

diff --git a/include/linux/filter.h b/include/linux/filter.h
index fc4e8f91b03d..4da8b2308174 100644
--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -30,6 +30,7 @@ struct sock;
 struct seccomp_data;
 struct bpf_prog_aux;
 struct xdp_rxq_info;
+struct xdp_buff;
 
 /* ArgX, context and stack frame pointer register positions. Note,
  * Arg1, Arg2, Arg3, etc are used as argument mappings of function
@@ -500,14 +501,6 @@ struct bpf_skb_data_end {
 	void *data_end;
 };
 
-struct xdp_buff {
-	void *data;
-	void *data_end;
-	void *data_meta;
-	void *data_hard_start;
-	struct xdp_rxq_info *rxq;
-};
-
 struct sk_msg_buff {
 	void *data;
 	void *data_end;
@@ -772,21 +765,6 @@ int xdp_do_redirect(struct net_device *dev,
 		    struct bpf_prog *prog);
 void xdp_do_flush_map(void);
 
-/* Drivers not supporting XDP metadata can use this helper, which
- * rejects any room expansion for metadata as a result.
- */
-static __always_inline void
-xdp_set_data_meta_invalid(struct xdp_buff *xdp)
-{
-	xdp->data_meta = xdp->data + 1;
-}
-
-static __always_inline bool
-xdp_data_meta_unsupported(const struct xdp_buff *xdp)
-{
-	return unlikely(xdp->data_meta > xdp->data);
-}
-
 void bpf_warn_invalid_xdp_action(u32 act);
 
 struct sock *do_sk_redirect_map(struct sk_buff *skb);
diff --git a/include/linux/if_tun.h b/include/linux/if_tun.h
index fd00170b494f..3d2996dc7d85 100644
--- a/include/linux/if_tun.h
+++ b/include/linux/if_tun.h
@@ -22,7 +22,7 @@
 #if defined(CONFIG_TUN) || defined(CONFIG_TUN_MODULE)
 struct socket *tun_get_socket(struct file *);
 struct ptr_ring *tun_get_tx_ring(struct file *file);
-bool tun_is_xdp_buff(void *ptr);
+bool tun_is_xdp_frame(void *ptr);
 void *tun_xdp_to_ptr(void *ptr);
 void *tun_ptr_to_xdp(void *ptr);
 void tun_ptr_free(void *ptr);
@@ -39,7 +39,7 @@ static inline struct ptr_ring *tun_get_tx_ring(struct file *f)
 {
 	return ERR_PTR(-EINVAL);
 }
-static inline bool tun_is_xdp_buff(void *ptr)
+static inline bool tun_is_xdp_frame(void *ptr)
 {
 	return false;
 }
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index cf44503ea81a..14e0777ffcfb 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -1165,7 +1165,7 @@ struct dev_ifalias {
  *	This function is used to set or query state related to XDP on the
  *	netdevice and manage BPF offload. See definition of
  *	enum bpf_netdev_command for details.
- * int (*ndo_xdp_xmit)(struct net_device *dev, struct xdp_buff *xdp);
+ * int (*ndo_xdp_xmit)(struct net_device *dev, struct xdp_frame *xdp);
  *	This function is used to submit a XDP packet for transmit on a
  *	netdevice.
  * void (*ndo_xdp_flush)(struct net_device *dev);
@@ -1356,7 +1356,7 @@ struct net_device_ops {
 	int			(*ndo_bpf)(struct net_device *dev,
 					   struct netdev_bpf *bpf);
 	int			(*ndo_xdp_xmit)(struct net_device *dev,
-						struct xdp_buff *xdp);
+						struct xdp_frame *xdp);
 	void			(*ndo_xdp_flush)(struct net_device *dev);
 };