1 files changed, 167 insertions, 27 deletions
diff --git a/include/net/xdp.h b/include/net/xdp.h
index b5b10f2b88e5..48efacbaa35d 100644
--- a/include/net/xdp.h
+++ b/include/net/xdp.h
@@ -11,6 +11,8 @@
 #include <linux/netdevice.h>
 #include <linux/skbuff.h> /* skb_shared_info */
 
+#include <net/page_pool/types.h>
+
 /**
  * DOC: XDP RX-queue information
  *
@@ -87,7 +89,7 @@ struct xdp_buff {
 	u32 flags; /* supported values defined in xdp_buff_flags */
 };
 
-static __always_inline bool xdp_buff_has_frags(struct xdp_buff *xdp)
+static __always_inline bool xdp_buff_has_frags(const struct xdp_buff *xdp)
 {
 	return !!(xdp->flags & XDP_FLAGS_HAS_FRAGS);
 }
@@ -102,7 +104,8 @@ 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)
+static __always_inline bool
+xdp_buff_is_frag_pfmemalloc(const struct xdp_buff *xdp)
 {
 	return !!(xdp->flags & XDP_FLAGS_FRAGS_PF_MEMALLOC);
 }
@@ -143,15 +146,16 @@ xdp_prepare_buff(struct xdp_buff *xdp, unsigned char *hard_start,
 	 SKB_DATA_ALIGN(sizeof(struct skb_shared_info)))
 
 static inline struct skb_shared_info *
-xdp_get_shared_info_from_buff(struct xdp_buff *xdp)
+xdp_get_shared_info_from_buff(const 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)
+static __always_inline unsigned int
+xdp_get_buff_len(const struct xdp_buff *xdp)
 {
 	unsigned int len = xdp->data_end - xdp->data;
-	struct skb_shared_info *sinfo;
+	const struct skb_shared_info *sinfo;
 
 	if (likely(!xdp_buff_has_frags(xdp)))
 		goto out;
@@ -162,26 +166,114 @@ out:
 	return len;
 }
 
+void xdp_return_frag(netmem_ref netmem, const struct xdp_buff *xdp);
+
+/**
+ * __xdp_buff_add_frag - attach frag to &xdp_buff
+ * @xdp: XDP buffer to attach the frag to
+ * @netmem: network memory containing the frag
+ * @offset: offset at which the frag starts
+ * @size: size of the frag
+ * @truesize: total memory size occupied by the frag
+ * @try_coalesce: whether to try coalescing the frags (not valid for XSk)
+ *
+ * Attach frag to the XDP buffer. If it currently has no frags attached,
+ * initialize the related fields, otherwise check that the frag number
+ * didn't reach the limit of ``MAX_SKB_FRAGS``. If possible, try coalescing
+ * the frag with the previous one.
+ * The function doesn't check/update the pfmemalloc bit. Please use the
+ * non-underscored wrapper in drivers.
+ *
+ * Return: true on success, false if there's no space for the frag in
+ * the shared info struct.
+ */
+static inline bool __xdp_buff_add_frag(struct xdp_buff *xdp, netmem_ref netmem,
+				       u32 offset, u32 size, u32 truesize,
+				       bool try_coalesce)
+{
+	struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp);
+	skb_frag_t *prev;
+	u32 nr_frags;
+
+	if (!xdp_buff_has_frags(xdp)) {
+		xdp_buff_set_frags_flag(xdp);
+
+		nr_frags = 0;
+		sinfo->xdp_frags_size = 0;
+		sinfo->xdp_frags_truesize = 0;
+
+		goto fill;
+	}
+
+	nr_frags = sinfo->nr_frags;
+	prev = &sinfo->frags[nr_frags - 1];
+
+	if (try_coalesce && netmem == skb_frag_netmem(prev) &&
+	    offset == skb_frag_off(prev) + skb_frag_size(prev)) {
+		skb_frag_size_add(prev, size);
+		/* Guaranteed to only decrement the refcount */
+		xdp_return_frag(netmem, xdp);
+	} else if (unlikely(nr_frags == MAX_SKB_FRAGS)) {
+		return false;
+	} else {
+fill:
+		__skb_fill_netmem_desc_noacc(sinfo, nr_frags++, netmem,
+					     offset, size);
+	}
+
+	sinfo->nr_frags = nr_frags;
+	sinfo->xdp_frags_size += size;
+	sinfo->xdp_frags_truesize += truesize;
+
+	return true;
+}
+
+/**
+ * xdp_buff_add_frag - attach frag to &xdp_buff
+ * @xdp: XDP buffer to attach the frag to
+ * @netmem: network memory containing the frag
+ * @offset: offset at which the frag starts
+ * @size: size of the frag
+ * @truesize: total memory size occupied by the frag
+ *
+ * Version of __xdp_buff_add_frag() which takes care of the pfmemalloc bit.
+ *
+ * Return: true on success, false if there's no space for the frag in
+ * the shared info struct.
+ */
+static inline bool xdp_buff_add_frag(struct xdp_buff *xdp, netmem_ref netmem,
+				     u32 offset, u32 size, u32 truesize)
+{
+	if (!__xdp_buff_add_frag(xdp, netmem, offset, size, truesize, true))
+		return false;
+
+	if (unlikely(netmem_is_pfmemalloc(netmem)))
+		xdp_buff_set_frag_pfmemalloc(xdp);
+
+	return true;
+}
+
 struct xdp_frame {
 	void *data;
-	u16 len;
-	u16 headroom;
+	u32 len;
+	u32 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.
+	 * while mem_type is valid on remote CPU.
 	 */
-	struct xdp_mem_info mem;
+	enum xdp_mem_type mem_type:32;
 	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)
+static __always_inline bool xdp_frame_has_frags(const struct xdp_frame *frame)
 {
 	return !!(frame->flags & XDP_FLAGS_HAS_FRAGS);
 }
 
-static __always_inline bool xdp_frame_is_frag_pfmemalloc(struct xdp_frame *frame)
+static __always_inline bool
+xdp_frame_is_frag_pfmemalloc(const struct xdp_frame *frame)
 {
 	return !!(frame->flags & XDP_FLAGS_FRAGS_PF_MEMALLOC);
 }
@@ -189,18 +281,16 @@ static __always_inline bool xdp_frame_is_frag_pfmemalloc(struct xdp_frame *frame
 #define XDP_BULK_QUEUE_SIZE	16
 struct xdp_frame_bulk {
 	int count;
-	void *xa;
-	void *q[XDP_BULK_QUEUE_SIZE];
+	netmem_ref 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;
+	bq->count = 0;
 }
 
 static inline struct skb_shared_info *
-xdp_get_shared_info_from_frame(struct xdp_frame *frame)
+xdp_get_shared_info_from_frame(const struct xdp_frame *frame)
 {
 	void *data_hard_start = frame->data - frame->headroom - sizeof(*frame);
 
@@ -226,7 +316,14 @@ 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;
+	struct skb_shared_info *sinfo = skb_shinfo(skb);
+
+	sinfo->nr_frags = nr_frags;
+	/*
+	 * ``destructor_arg`` is unionized with ``xdp_frags_{,true}size``,
+	 * reset it after that these fields aren't used anymore.
+	 */
+	sinfo->destructor_arg = NULL;
 
 	skb->len += size;
 	skb->data_len += size;
@@ -238,17 +335,19 @@ xdp_update_skb_shared_info(struct sk_buff *skb, u8 nr_frags,
 void xdp_warn(const char *msg, const char *func, const int line);
 #define XDP_WARN(msg) xdp_warn(msg, __func__, __LINE__)
 
+struct sk_buff *xdp_build_skb_from_buff(const struct xdp_buff *xdp);
+struct sk_buff *xdp_build_skb_from_zc(struct xdp_buff *xdp);
 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)
+void xdp_convert_frame_to_buff(const struct xdp_frame *frame,
+			       struct xdp_buff *xdp)
 {
 	xdp->data_hard_start = frame->data - frame->headroom - sizeof(*frame);
 	xdp->data = frame->data;
@@ -259,7 +358,7 @@ void xdp_convert_frame_to_buff(struct xdp_frame *frame, struct xdp_buff *xdp)
 }
 
 static inline
-int xdp_update_frame_from_buff(struct xdp_buff *xdp,
+int xdp_update_frame_from_buff(const struct xdp_buff *xdp,
 			       struct xdp_frame *xdp_frame)
 {
 	int metasize, headroom;
@@ -301,24 +400,33 @@ struct xdp_frame *xdp_convert_buff_to_frame(struct xdp_buff *xdp)
 	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;
+	/* rxq only valid until napi_schedule ends, convert to xdp_mem_type */
+	xdp_frame->mem_type = xdp->rxq->mem.type;
 
 	return xdp_frame;
 }
 
-void __xdp_return(void *data, struct xdp_mem_info *mem, bool napi_direct,
-		  struct xdp_buff *xdp);
+void __xdp_return(netmem_ref netmem, enum xdp_mem_type mem_type,
+		  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);
 
-static __always_inline unsigned int xdp_get_frame_len(struct xdp_frame *xdpf)
+static inline void xdp_flush_frame_bulk(struct xdp_frame_bulk *bq)
+{
+	if (unlikely(!bq->count))
+		return;
+
+	page_pool_put_netmem_bulk(bq->q, bq->count);
+	bq->count = 0;
+}
+
+static __always_inline unsigned int
+xdp_get_frame_len(const struct xdp_frame *xdpf)
 {
-	struct skb_shared_info *sinfo;
+	const struct skb_shared_info *sinfo;
 	unsigned int len = xdpf->len;
 
 	if (likely(!xdp_frame_has_frags(xdpf)))
@@ -350,6 +458,38 @@ 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);
+int xdp_reg_page_pool(struct page_pool *pool);
+void xdp_unreg_page_pool(const struct page_pool *pool);
+void xdp_rxq_info_attach_page_pool(struct xdp_rxq_info *xdp_rxq,
+				   const struct page_pool *pool);
+
+/**
+ * xdp_rxq_info_attach_mem_model - attach registered mem info to RxQ info
+ * @xdp_rxq: XDP RxQ info to attach the memory info to
+ * @mem: already registered memory info
+ *
+ * If the driver registers its memory providers manually, it must use this
+ * function instead of xdp_rxq_info_reg_mem_model().
+ */
+static inline void
+xdp_rxq_info_attach_mem_model(struct xdp_rxq_info *xdp_rxq,
+			      const struct xdp_mem_info *mem)
+{
+	xdp_rxq->mem = *mem;
+}
+
+/**
+ * xdp_rxq_info_detach_mem_model - detach registered mem info from RxQ info
+ * @xdp_rxq: XDP RxQ info to detach the memory info from
+ *
+ * If the driver registers its memory providers manually and then attaches it
+ * via xdp_rxq_info_attach_mem_model(), it must call this function before
+ * xdp_rxq_info_unreg().
+ */
+static inline void xdp_rxq_info_detach_mem_model(struct xdp_rxq_info *xdp_rxq)
+{
+	xdp_rxq->mem = (struct xdp_mem_info){ };
+}
 
 /* Drivers not supporting XDP metadata can use this helper, which
  * rejects any room expansion for metadata as a result.