Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 412 insertions, 0 deletions

diff --git a/include/net/xdp.h b/include/net/xdp.h
new file mode 100644
index 000000000..55dbc68bf
--- /dev/null
+++ b/include/net/xdp.h
@@ -0,0 +1,412 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* include/net/xdp.h
+ *
+ * Copyright (c) 2017 Jesper Dangaard Brouer, Red Hat Inc.
+ */
+#ifndef __LINUX_NET_XDP_H__
+#define __LINUX_NET_XDP_H__
+
+#include <linux/skbuff.h> /* skb_shared_info */
+
+/**
+ * DOC: XDP RX-queue information
+ *
+ * The XDP RX-queue info (xdp_rxq_info) is associated with the driver
+ * level RX-ring queues.  It is information that is specific to how
+ * the driver have configured a given RX-ring queue.
+ *
+ * Each xdp_buff frame received in the driver carries a (pointer)
+ * reference to this xdp_rxq_info structure.  This provides the XDP
+ * data-path read-access to RX-info for both kernel and bpf-side
+ * (limited subset).
+ *
+ * For now, direct access is only safe while running in NAPI/softirq
+ * context.  Contents are read-mostly and must not be updated during
+ * driver NAPI/softirq poll.
+ *
+ * The driver usage API is a register and unregister API.
+ *
+ * The struct is not directly tied to the XDP prog.  A new XDP prog
+ * can be attached as long as it doesn't change the underlying
+ * RX-ring.  If the RX-ring does change significantly, the NIC driver
+ * naturally need to stop the RX-ring before purging and reallocating
+ * memory.  In that process the driver MUST call unregister (which
+ * also applies for driver shutdown and unload).  The register API is
+ * also mandatory during RX-ring setup.
+ */
+
+enum xdp_mem_type {
+	MEM_TYPE_PAGE_SHARED = 0, /* Split-page refcnt based model */
+	MEM_TYPE_PAGE_ORDER0,     /* Orig XDP full page model */
+	MEM_TYPE_PAGE_POOL,
+	MEM_TYPE_XSK_BUFF_POOL,
+	MEM_TYPE_MAX,
+};
+
+/* XDP flags for ndo_xdp_xmit */
+#define XDP_XMIT_FLUSH		(1U << 0)	/* doorbell signal consumer */
+#define XDP_XMIT_FLAGS_MASK	XDP_XMIT_FLUSH
+
+struct xdp_mem_info {
+	u32 type; /* enum xdp_mem_type, but known size type */
+	u32 id;
+};
+
+struct page_pool;
+
+struct xdp_rxq_info {
+	struct net_device *dev;
+	u32 queue_index;
+	u32 reg_state;
+	struct xdp_mem_info mem;
+	unsigned int napi_id;
+	u32 frag_size;
+} ____cacheline_aligned; /* perf critical, avoid false-sharing */
+
+struct xdp_txq_info {
+	struct net_device *dev;
+};
+
+enum xdp_buff_flags {
+	XDP_FLAGS_HAS_FRAGS		= BIT(0), /* non-linear xdp buff */
+	XDP_FLAGS_FRAGS_PF_MEMALLOC	= BIT(1), /* xdp paged memory is under
+						   * pressure
+						   */
+};
+
+struct xdp_buff {
+	void *data;
+	void *data_end;
+	void *data_meta;
+	void *data_hard_start;
+	struct xdp_rxq_info *rxq;
+	struct xdp_txq_info *txq;
+	u32 frame_sz; /* frame size to deduce data_hard_end/reserved tailroom*/
+	u32 flags; /* supported values defined in xdp_buff_flags */
+};
+
+static __always_inline bool xdp_buff_has_frags(struct xdp_buff *xdp)
+{
+	return !!(xdp->flags & XDP_FLAGS_HAS_FRAGS);
+}
+
+static __always_inline void xdp_buff_set_frags_flag(struct xdp_buff *xdp)
+{
+	xdp->flags |= XDP_FLAGS_HAS_FRAGS;
+}
+
+static __always_inline void xdp_buff_clear_frags_flag(struct xdp_buff *xdp)
+{
+	xdp->flags &= ~XDP_FLAGS_HAS_FRAGS;
+}
+
+static __always_inline bool xdp_buff_is_frag_pfmemalloc(struct xdp_buff *xdp)
+{
+	return !!(xdp->flags & XDP_FLAGS_FRAGS_PF_MEMALLOC);
+}
+
+static __always_inline void xdp_buff_set_frag_pfmemalloc(struct xdp_buff *xdp)
+{
+	xdp->flags |= XDP_FLAGS_FRAGS_PF_MEMALLOC;
+}
+
+static __always_inline void
+xdp_init_buff(struct xdp_buff *xdp, u32 frame_sz, struct xdp_rxq_info *rxq)
+{
+	xdp->frame_sz = frame_sz;
+	xdp->rxq = rxq;
+	xdp->flags = 0;
+}
+
+static __always_inline void
+xdp_prepare_buff(struct xdp_buff *xdp, unsigned char *hard_start,
+		 int headroom, int data_len, const bool meta_valid)
+{
+	unsigned char *data = hard_start + headroom;
+
+	xdp->data_hard_start = hard_start;
+	xdp->data = data;
+	xdp->data_end = data + data_len;
+	xdp->data_meta = meta_valid ? data : data + 1;
+}
+
+/* Reserve memory area at end-of data area.
+ *
+ * This macro reserves tailroom in the XDP buffer by limiting the
+ * XDP/BPF data access to data_hard_end.  Notice same area (and size)
+ * is used for XDP_PASS, when constructing the SKB via build_skb().
+ */
+#define xdp_data_hard_end(xdp)				\
+	((xdp)->data_hard_start + (xdp)->frame_sz -	\
+	 SKB_DATA_ALIGN(sizeof(struct skb_shared_info)))
+
+static inline struct skb_shared_info *
+xdp_get_shared_info_from_buff(struct xdp_buff *xdp)
+{
+	return (struct skb_shared_info *)xdp_data_hard_end(xdp);
+}
+
+static __always_inline unsigned int xdp_get_buff_len(struct xdp_buff *xdp)
+{
+	unsigned int len = xdp->data_end - xdp->data;
+	struct skb_shared_info *sinfo;
+
+	if (likely(!xdp_buff_has_frags(xdp)))
+		goto out;
+
+	sinfo = xdp_get_shared_info_from_buff(xdp);
+	len += sinfo->xdp_frags_size;
+out:
+	return len;
+}
+
+struct xdp_frame {
+	void *data;
+	u16 len;
+	u16 headroom;
+	u32 metasize; /* uses lower 8-bits */
+	/* Lifetime of xdp_rxq_info is limited to NAPI/enqueue time,
+	 * while mem info is valid on remote CPU.
+	 */
+	struct xdp_mem_info mem;
+	struct net_device *dev_rx; /* used by cpumap */
+	u32 frame_sz;
+	u32 flags; /* supported values defined in xdp_buff_flags */
+};
+
+static __always_inline bool xdp_frame_has_frags(struct xdp_frame *frame)
+{
+	return !!(frame->flags & XDP_FLAGS_HAS_FRAGS);
+}
+
+static __always_inline bool xdp_frame_is_frag_pfmemalloc(struct xdp_frame *frame)
+{
+	return !!(frame->flags & XDP_FLAGS_FRAGS_PF_MEMALLOC);
+}
+
+#define XDP_BULK_QUEUE_SIZE	16
+struct xdp_frame_bulk {
+	int count;
+	void *xa;
+	void *q[XDP_BULK_QUEUE_SIZE];
+};
+
+static __always_inline void xdp_frame_bulk_init(struct xdp_frame_bulk *bq)
+{
+	/* bq->count will be zero'ed when bq->xa gets updated */
+	bq->xa = NULL;
+}
+
+static inline struct skb_shared_info *
+xdp_get_shared_info_from_frame(struct xdp_frame *frame)
+{
+	void *data_hard_start = frame->data - frame->headroom - sizeof(*frame);
+
+	return (struct skb_shared_info *)(data_hard_start + frame->frame_sz -
+				SKB_DATA_ALIGN(sizeof(struct skb_shared_info)));
+}
+
+struct xdp_cpumap_stats {
+	unsigned int redirect;
+	unsigned int pass;
+	unsigned int drop;
+};
+
+/* Clear kernel pointers in xdp_frame */
+static inline void xdp_scrub_frame(struct xdp_frame *frame)
+{
+	frame->data = NULL;
+	frame->dev_rx = NULL;
+}
+
+static inline void
+xdp_update_skb_shared_info(struct sk_buff *skb, u8 nr_frags,
+			   unsigned int size, unsigned int truesize,
+			   bool pfmemalloc)
+{
+	skb_shinfo(skb)->nr_frags = nr_frags;
+
+	skb->len += size;
+	skb->data_len += size;
+	skb->truesize += truesize;
+	skb->pfmemalloc |= pfmemalloc;
+}
+
+/* Avoids inlining WARN macro in fast-path */
+void xdp_warn(const char *msg, const char *func, const int line);
+#define XDP_WARN(msg) xdp_warn(msg, __func__, __LINE__)
+
+struct xdp_frame *xdp_convert_zc_to_xdp_frame(struct xdp_buff *xdp);
+struct sk_buff *__xdp_build_skb_from_frame(struct xdp_frame *xdpf,
+					   struct sk_buff *skb,
+					   struct net_device *dev);
+struct sk_buff *xdp_build_skb_from_frame(struct xdp_frame *xdpf,
+					 struct net_device *dev);
+int xdp_alloc_skb_bulk(void **skbs, int n_skb, gfp_t gfp);
+struct xdp_frame *xdpf_clone(struct xdp_frame *xdpf);
+
+static inline
+void xdp_convert_frame_to_buff(struct xdp_frame *frame, struct xdp_buff *xdp)
+{
+	xdp->data_hard_start = frame->data - frame->headroom - sizeof(*frame);
+	xdp->data = frame->data;
+	xdp->data_end = frame->data + frame->len;
+	xdp->data_meta = frame->data - frame->metasize;
+	xdp->frame_sz = frame->frame_sz;
+	xdp->flags = frame->flags;
+}
+
+static inline
+int xdp_update_frame_from_buff(struct xdp_buff *xdp,
+			       struct xdp_frame *xdp_frame)
+{
+	int metasize, headroom;
+
+	/* Assure headroom is available for storing info */
+	headroom = xdp->data - xdp->data_hard_start;
+	metasize = xdp->data - xdp->data_meta;
+	metasize = metasize > 0 ? metasize : 0;
+	if (unlikely((headroom - metasize) < sizeof(*xdp_frame)))
+		return -ENOSPC;
+
+	/* Catch if driver didn't reserve tailroom for skb_shared_info */
+	if (unlikely(xdp->data_end > xdp_data_hard_end(xdp))) {
+		XDP_WARN("Driver BUG: missing reserved tailroom");
+		return -ENOSPC;
+	}
+
+	xdp_frame->data = xdp->data;
+	xdp_frame->len  = xdp->data_end - xdp->data;
+	xdp_frame->headroom = headroom - sizeof(*xdp_frame);
+	xdp_frame->metasize = metasize;
+	xdp_frame->frame_sz = xdp->frame_sz;
+	xdp_frame->flags = xdp->flags;
+
+	return 0;
+}
+
+/* Convert xdp_buff to xdp_frame */
+static inline
+struct xdp_frame *xdp_convert_buff_to_frame(struct xdp_buff *xdp)
+{
+	struct xdp_frame *xdp_frame;
+
+	if (xdp->rxq->mem.type == MEM_TYPE_XSK_BUFF_POOL)
+		return xdp_convert_zc_to_xdp_frame(xdp);
+
+	/* Store info in top of packet */
+	xdp_frame = xdp->data_hard_start;
+	if (unlikely(xdp_update_frame_from_buff(xdp, xdp_frame) < 0))
+		return NULL;
+
+	/* rxq only valid until napi_schedule ends, convert to xdp_mem_info */
+	xdp_frame->mem = xdp->rxq->mem;
+
+	return xdp_frame;
+}
+
+void __xdp_return(void *data, struct xdp_mem_info *mem, bool napi_direct,
+		  struct xdp_buff *xdp);
+void xdp_return_frame(struct xdp_frame *xdpf);
+void xdp_return_frame_rx_napi(struct xdp_frame *xdpf);
+void xdp_return_buff(struct xdp_buff *xdp);
+void xdp_flush_frame_bulk(struct xdp_frame_bulk *bq);
+void xdp_return_frame_bulk(struct xdp_frame *xdpf,
+			   struct xdp_frame_bulk *bq);
+
+/* When sending xdp_frame into the network stack, then there is no
+ * return point callback, which is needed to release e.g. DMA-mapping
+ * resources with page_pool.  Thus, have explicit function to release
+ * frame resources.
+ */
+void __xdp_release_frame(void *data, struct xdp_mem_info *mem);
+static inline void xdp_release_frame(struct xdp_frame *xdpf)
+{
+	struct xdp_mem_info *mem = &xdpf->mem;
+	struct skb_shared_info *sinfo;
+	int i;
+
+	/* Curr only page_pool needs this */
+	if (mem->type != MEM_TYPE_PAGE_POOL)
+		return;
+
+	if (likely(!xdp_frame_has_frags(xdpf)))
+		goto out;
+
+	sinfo = xdp_get_shared_info_from_frame(xdpf);
+	for (i = 0; i < sinfo->nr_frags; i++) {
+		struct page *page = skb_frag_page(&sinfo->frags[i]);
+
+		__xdp_release_frame(page_address(page), mem);
+	}
+out:
+	__xdp_release_frame(xdpf->data, mem);
+}
+
+static __always_inline unsigned int xdp_get_frame_len(struct xdp_frame *xdpf)
+{
+	struct skb_shared_info *sinfo;
+	unsigned int len = xdpf->len;
+
+	if (likely(!xdp_frame_has_frags(xdpf)))
+		goto out;
+
+	sinfo = xdp_get_shared_info_from_frame(xdpf);
+	len += sinfo->xdp_frags_size;
+out:
+	return len;
+}
+
+int __xdp_rxq_info_reg(struct xdp_rxq_info *xdp_rxq,
+		       struct net_device *dev, u32 queue_index,
+		       unsigned int napi_id, u32 frag_size);
+static inline int
+xdp_rxq_info_reg(struct xdp_rxq_info *xdp_rxq,
+		 struct net_device *dev, u32 queue_index,
+		 unsigned int napi_id)
+{
+	return __xdp_rxq_info_reg(xdp_rxq, dev, queue_index, napi_id, 0);
+}
+
+void xdp_rxq_info_unreg(struct xdp_rxq_info *xdp_rxq);
+void xdp_rxq_info_unused(struct xdp_rxq_info *xdp_rxq);
+bool xdp_rxq_info_is_reg(struct xdp_rxq_info *xdp_rxq);
+int xdp_rxq_info_reg_mem_model(struct xdp_rxq_info *xdp_rxq,
+			       enum xdp_mem_type type, void *allocator);
+void xdp_rxq_info_unreg_mem_model(struct xdp_rxq_info *xdp_rxq);
+int xdp_reg_mem_model(struct xdp_mem_info *mem,
+		      enum xdp_mem_type type, void *allocator);
+void xdp_unreg_mem_model(struct xdp_mem_info *mem);
+
+/* 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);
+}
+
+static inline bool xdp_metalen_invalid(unsigned long metalen)
+{
+	return (metalen & (sizeof(__u32) - 1)) || (metalen > 32);
+}
+
+struct xdp_attachment_info {
+	struct bpf_prog *prog;
+	u32 flags;
+};
+
+struct netdev_bpf;
+void xdp_attachment_setup(struct xdp_attachment_info *info,
+			  struct netdev_bpf *bpf);
+
+#define DEV_MAP_BULK_SIZE XDP_BULK_QUEUE_SIZE
+
+#endif /* __LINUX_NET_XDP_H__ */