mvneta: introduce XDP multi-buffer support

Acked-by Jesper Dangaard Brouer <[email protected]>

---
 include/linux/skbuff.h | 1 +
 1 file changed, 1 insertion(+)

include/linux/skbuff.h +1 -0

index bf11e1fbd69b..8131d0de7559 100644
@@ -557,6 +557,7 @@ struct skb_shared_info {
 	 * Warning : all fields before dataref are cleared in __alloc_skb()
 	 */
 	atomic_t	dataref;
+	unsigned int	xdp_frags_size;
 
 	/* Intermediate layers must ensure that destructor_arg
 	 * remains valid until skb destructor */

Signature · 1 line

2.34.1

Lorenzo Bianconi

author

2022-01-21 10:11 UTC #2 lore raw

PATCH v23 2/23 xdp: introduce flags field in xdp_buff/xdp_frame

Introduce flags field in xdp_frame and xdp_buffer data structures to define additional buffer features. At the moment the only supported buffer feature is frags bit (XDP_FLAGS_HAS_FRAGS). frags bit is used to specify if this is a linear buffer (XDP_FLAGS_HAS_FRAGS not set) or a frags frame (XDP_FLAGS_HAS_FRAGS set). In the latter case the driver is expected to initialize the skb_shared_info structure at the end of the first buffer to link together subsequent buffers belonging to the same frame.

Acked-by Toke Hoiland-Jorgensen <[email protected]>

Acked-by Jesper Dangaard Brouer <[email protected]>

---
 include/net/xdp.h | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)

include/net/xdp.h +29 -0

index 8f0812e4996d..485e9495a690 100644
@@ -66,6 +66,10 @@ struct xdp_txq_info {
 	struct net_device *dev;
 };
 
+enum xdp_buff_flags {
+	XDP_FLAGS_HAS_FRAGS	= BIT(0), /* non-linear xdp buff */
+};
+
 struct xdp_buff {
 	void *data;
 	void *data_end;

@@ -74,13 +78,30 @@ struct xdp_buff {
 	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 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

@@ -122,8 +143,14 @@ struct xdp_frame {
 	 */
 	struct xdp_mem_info mem;
 	struct net_device *dev_rx; /* used by cpumap */
+	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);
+}
+
 #define XDP_BULK_QUEUE_SIZE	16
 struct xdp_frame_bulk {
 	int count;

@@ -180,6 +207,7 @@ void xdp_convert_frame_to_buff(struct xdp_frame *frame, struct xdp_buff *xdp)
 	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

@@ -206,6 +234,7 @@ int xdp_update_frame_from_buff(struct xdp_buff *xdp,
 	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;
 }

Signature · 1 line

2.34.1

Lorenzo Bianconi

author

2022-01-21 10:11 UTC #3 lore raw

PATCH v23 3/23 net: mvneta: update frags bit before passing the xdp buffer to eBPF layer

Update frags bit (XDP_FLAGS_HAS_FRAGS) in xdp_buff to notify XDP/eBPF layer and XDP remote drivers if this is a "non-linear" XDP buffer. Access skb_shared_info only if XDP_FLAGS_HAS_FRAGS flag is set in order to avoid possible cache-misses.

Acked-by Toke Hoiland-Jorgensen <[email protected]>

---
 drivers/net/ethernet/marvell/mvneta.c | 23 ++++++++++++++++++-----
 1 file changed, 18 insertions(+), 5 deletions(-)

drivers/net/ethernet/marvell/mvneta.c +18 -5

index 83c8908f0cc7..a3e74a4b19dc 100644
@@ -2065,9 +2065,14 @@ mvneta_xdp_put_buff(struct mvneta_port *pp, struct mvneta_rx_queue *rxq,
 {
 	int i;
 
+	if (likely(!xdp_buff_has_frags(xdp)))
+		goto out;
+
 	for (i = 0; i < sinfo->nr_frags; i++)
 		page_pool_put_full_page(rxq->page_pool,
 					skb_frag_page(&sinfo->frags[i]), true);
+
+out:
 	page_pool_put_page(rxq->page_pool, virt_to_head_page(xdp->data),
 			   sync_len, true);
 }

@@ -2269,7 +2274,6 @@ mvneta_swbm_rx_frame(struct mvneta_port *pp,
 	int data_len = -MVNETA_MH_SIZE, len;
 	struct net_device *dev = pp->dev;
 	enum dma_data_direction dma_dir;
-	struct skb_shared_info *sinfo;
 
 	if (*size > MVNETA_MAX_RX_BUF_SIZE) {
 		len = MVNETA_MAX_RX_BUF_SIZE;

@@ -2289,11 +2293,9 @@ mvneta_swbm_rx_frame(struct mvneta_port *pp,
 
 	/* Prefetch header */
 	prefetch(data);
+	xdp_buff_clear_frags_flag(xdp);
 	xdp_prepare_buff(xdp, data, pp->rx_offset_correction + MVNETA_MH_SIZE,
 			 data_len, false);
-
-	sinfo = xdp_get_shared_info_from_buff(xdp);
-	sinfo->nr_frags = 0;
 }
 
 static void

@@ -2327,6 +2329,9 @@ mvneta_swbm_add_rx_fragment(struct mvneta_port *pp,
 		skb_frag_off_set(frag, pp->rx_offset_correction);
 		skb_frag_size_set(frag, data_len);
 		__skb_frag_set_page(frag, page);
+
+		if (!xdp_buff_has_frags(xdp))
+			xdp_buff_set_frags_flag(xdp);
 	} else {
 		page_pool_put_full_page(rxq->page_pool, page, true);
 	}

@@ -2348,8 +2353,12 @@ mvneta_swbm_build_skb(struct mvneta_port *pp, struct page_pool *pool,
 		      struct xdp_buff *xdp, u32 desc_status)
 {
 	struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp);
-	int i, num_frags = sinfo->nr_frags;
 	struct sk_buff *skb;
+	u8 num_frags;
+	int i;
+
+	if (unlikely(xdp_buff_has_frags(xdp)))
+		num_frags = sinfo->nr_frags;
 
 	skb = build_skb(xdp->data_hard_start, PAGE_SIZE);
 	if (!skb)

@@ -2361,6 +2370,9 @@ mvneta_swbm_build_skb(struct mvneta_port *pp, struct page_pool *pool,
 	skb_put(skb, xdp->data_end - xdp->data);
 	skb->ip_summed = mvneta_rx_csum(pp, desc_status);
 
+	if (likely(!xdp_buff_has_frags(xdp)))
+		goto out;
+
 	for (i = 0; i < num_frags; i++) {
 		skb_frag_t *frag = &sinfo->frags[i];

@@ -2369,6 +2381,7 @@ mvneta_swbm_build_skb(struct mvneta_port *pp, struct page_pool *pool,
 				skb_frag_size(frag), PAGE_SIZE);
 	}
 
+out:
 	return skb;
 }

Signature · 1 line

2.34.1

Lorenzo Bianconi

author

2022-01-21 10:11 UTC #4 lore raw

PATCH v23 4/23 net: mvneta: simplify mvneta_swbm_add_rx_fragment management

Relying on xdp frags bit, remove skb_shared_info structure allocated on the stack in mvneta_rx_swbm routine and simplify mvneta_swbm_add_rx_fragment accessing skb_shared_info in the xdp_buff structure directly. There is no performance penalty in this approach since mvneta_swbm_add_rx_fragment is run just for xdp frags use-case.

Acked-by Toke Hoiland-Jorgensen <[email protected]>

---
 drivers/net/ethernet/marvell/mvneta.c | 42 ++++++++++-----------------
 1 file changed, 15 insertions(+), 27 deletions(-)

drivers/net/ethernet/marvell/mvneta.c +15 ~~-27~~

index a3e74a4b19dc..bc70292dda43 100644
@@ -2060,9 +2060,9 @@ int mvneta_rx_refill_queue(struct mvneta_port *pp, struct mvneta_rx_queue *rxq)
 
 static void
 mvneta_xdp_put_buff(struct mvneta_port *pp, struct mvneta_rx_queue *rxq,
-		    struct xdp_buff *xdp, struct skb_shared_info *sinfo,
-		    int sync_len)
+		    struct xdp_buff *xdp, int sync_len)
 {
+	struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp);
 	int i;
 
 	if (likely(!xdp_buff_has_frags(xdp)))

@@ -2210,7 +2210,6 @@ mvneta_run_xdp(struct mvneta_port *pp, struct mvneta_rx_queue *rxq,
 	       struct bpf_prog *prog, struct xdp_buff *xdp,
 	       u32 frame_sz, struct mvneta_stats *stats)
 {
-	struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp);
 	unsigned int len, data_len, sync;
 	u32 ret, act;

@@ -2231,7 +2230,7 @@ mvneta_run_xdp(struct mvneta_port *pp, struct mvneta_rx_queue *rxq,
 
 		err = xdp_do_redirect(pp->dev, xdp, prog);
 		if (unlikely(err)) {
-			mvneta_xdp_put_buff(pp, rxq, xdp, sinfo, sync);
+			mvneta_xdp_put_buff(pp, rxq, xdp, sync);
 			ret = MVNETA_XDP_DROPPED;
 		} else {
 			ret = MVNETA_XDP_REDIR;

@@ -2242,7 +2241,7 @@ mvneta_run_xdp(struct mvneta_port *pp, struct mvneta_rx_queue *rxq,
 	case XDP_TX:
 		ret = mvneta_xdp_xmit_back(pp, xdp);
 		if (ret != MVNETA_XDP_TX)
-			mvneta_xdp_put_buff(pp, rxq, xdp, sinfo, sync);
+			mvneta_xdp_put_buff(pp, rxq, xdp, sync);
 		break;
 	default:
 		bpf_warn_invalid_xdp_action(pp->dev, prog, act);

@@ -2251,7 +2250,7 @@ mvneta_run_xdp(struct mvneta_port *pp, struct mvneta_rx_queue *rxq,
 		trace_xdp_exception(pp->dev, prog, act);
 		fallthrough;
 	case XDP_DROP:
-		mvneta_xdp_put_buff(pp, rxq, xdp, sinfo, sync);
+		mvneta_xdp_put_buff(pp, rxq, xdp, sync);
 		ret = MVNETA_XDP_DROPPED;
 		stats->xdp_drop++;
 		break;

@@ -2303,9 +2302,9 @@ mvneta_swbm_add_rx_fragment(struct mvneta_port *pp,
 			    struct mvneta_rx_desc *rx_desc,
 			    struct mvneta_rx_queue *rxq,
 			    struct xdp_buff *xdp, int *size,
-			    struct skb_shared_info *xdp_sinfo,
 			    struct page *page)
 {
+	struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp);
 	struct net_device *dev = pp->dev;
 	enum dma_data_direction dma_dir;
 	int data_len, len;

@@ -2323,8 +2322,11 @@ mvneta_swbm_add_rx_fragment(struct mvneta_port *pp,
 				len, dma_dir);
 	rx_desc->buf_phys_addr = 0;
 
-	if (data_len > 0 && xdp_sinfo->nr_frags < MAX_SKB_FRAGS) {
-		skb_frag_t *frag = &xdp_sinfo->frags[xdp_sinfo->nr_frags++];
+	if (!xdp_buff_has_frags(xdp))
+		sinfo->nr_frags = 0;
+
+	if (data_len > 0 && sinfo->nr_frags < MAX_SKB_FRAGS) {
+		skb_frag_t *frag = &sinfo->frags[sinfo->nr_frags++];
 
 		skb_frag_off_set(frag, pp->rx_offset_correction);
 		skb_frag_size_set(frag, data_len);

@@ -2335,16 +2337,6 @@ mvneta_swbm_add_rx_fragment(struct mvneta_port *pp,
 	} else {
 		page_pool_put_full_page(rxq->page_pool, page, true);
 	}
-
-	/* last fragment */
-	if (len == *size) {
-		struct skb_shared_info *sinfo;
-
-		sinfo = xdp_get_shared_info_from_buff(xdp);
-		sinfo->nr_frags = xdp_sinfo->nr_frags;
-		memcpy(sinfo->frags, xdp_sinfo->frags,
-		       sinfo->nr_frags * sizeof(skb_frag_t));
-	}
 	*size -= len;
 }

@@ -2392,7 +2384,6 @@ static int mvneta_rx_swbm(struct napi_struct *napi,
 {
 	int rx_proc = 0, rx_todo, refill, size = 0;
 	struct net_device *dev = pp->dev;
-	struct skb_shared_info sinfo;
 	struct mvneta_stats ps = {};
 	struct bpf_prog *xdp_prog;
 	u32 desc_status, frame_sz;

@@ -2401,8 +2392,6 @@ static int mvneta_rx_swbm(struct napi_struct *napi,
 	xdp_init_buff(&xdp_buf, PAGE_SIZE, &rxq->xdp_rxq);
 	xdp_buf.data_hard_start = NULL;
 
-	sinfo.nr_frags = 0;
-
 	/* Get number of received packets */
 	rx_todo = mvneta_rxq_busy_desc_num_get(pp, rxq);

@@ -2444,7 +2433,7 @@ static int mvneta_rx_swbm(struct napi_struct *napi,
 			}
 
 			mvneta_swbm_add_rx_fragment(pp, rx_desc, rxq, &xdp_buf,
-						    &size, &sinfo, page);
+						    &size, page);
 		} /* Middle or Last descriptor */
 
 		if (!(rx_status & MVNETA_RXD_LAST_DESC))

@@ -2452,7 +2441,7 @@ static int mvneta_rx_swbm(struct napi_struct *napi,
 			continue;
 
 		if (size) {
-			mvneta_xdp_put_buff(pp, rxq, &xdp_buf, &sinfo, -1);
+			mvneta_xdp_put_buff(pp, rxq, &xdp_buf, -1);
 			goto next;
 		}

@@ -2464,7 +2453,7 @@ static int mvneta_rx_swbm(struct napi_struct *napi,
 		if (IS_ERR(skb)) {
 			struct mvneta_pcpu_stats *stats = this_cpu_ptr(pp->stats);
 
-			mvneta_xdp_put_buff(pp, rxq, &xdp_buf, &sinfo, -1);
+			mvneta_xdp_put_buff(pp, rxq, &xdp_buf, -1);
 
 			u64_stats_update_begin(&stats->syncp);
 			stats->es.skb_alloc_error++;

@@ -2481,11 +2470,10 @@ static int mvneta_rx_swbm(struct napi_struct *napi,
 		napi_gro_receive(napi, skb);
 next:
 		xdp_buf.data_hard_start = NULL;
-		sinfo.nr_frags = 0;
 	}
 
 	if (xdp_buf.data_hard_start)
-		mvneta_xdp_put_buff(pp, rxq, &xdp_buf, &sinfo, -1);
+		mvneta_xdp_put_buff(pp, rxq, &xdp_buf, -1);
 
 	if (ps.xdp_redirect)
 		xdp_do_flush_map();

Signature · 1 line

2.34.1

Lorenzo Bianconi

author

2022-01-21 10:11 UTC #5 lore raw

PATCH v23 5/23 net: xdp: add xdp_update_skb_shared_info utility routine

Introduce xdp_update_skb_shared_info routine to update frags array metadata in skb_shared_info data structure converting to a skb from a xdp_buff or xdp_frame.
According to the current skb_shared_info architecture in xdp_frame/xdp_buff and to the xdp frags support, there is
no need to run skb_add_rx_frag() and reset frags array converting the buffer to a skb since the frag array will be in the same position for xdp_buff/xdp_frame and for the skb, we just need to update memory metadata.
Introduce XDP_FLAGS_PF_MEMALLOC flag in xdp_buff_flags in order to mark the xdp_buff or xdp_frame as under memory-pressure if pages of the frags array are under memory pressure. Doing so we can avoid looping over all fragments in xdp_update_skb_shared_info routine. The driver is expected to set the flag constructing the xdp_buffer using xdp_buff_set_frag_pfmemalloc utility routine.
Rely on xdp_update_skb_shared_info in __xdp_build_skb_from_frame routine converting the non-linear xdp_frame to a skb after performing a XDP_REDIRECT.

Acked-by Toke Hoiland-Jorgensen <[email protected]>

Acked-by Jesper Dangaard Brouer <[email protected]>

---
 include/net/xdp.h | 33 ++++++++++++++++++++++++++++++++-
 net/core/xdp.c    | 12 ++++++++++++
 2 files changed, 44 insertions(+), 1 deletion(-)

include/net/xdp.h +32 -1

index 485e9495a690..1f8641ec658e 100644
@@ -67,7 +67,10 @@ struct xdp_txq_info {
 };
 
 enum xdp_buff_flags {
-	XDP_FLAGS_HAS_FRAGS	= BIT(0), /* non-linear xdp buff */
+	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 {

@@ -96,6 +99,16 @@ 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)
 {

@@ -151,6 +164,11 @@ 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;

@@ -186,6 +204,19 @@ static inline void xdp_scrub_frame(struct xdp_frame *frame)
 	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__)

net/core/xdp.c +12 -0

index 7aba35504986..9e469f5f434c 100644
@@ -561,8 +561,14 @@ struct sk_buff *__xdp_build_skb_from_frame(struct xdp_frame *xdpf,
 					   struct sk_buff *skb,
 					   struct net_device *dev)
 {
+	struct skb_shared_info *sinfo = xdp_get_shared_info_from_frame(xdpf);
 	unsigned int headroom, frame_size;
 	void *hard_start;
+	u8 nr_frags;
+
+	/* xdp frags frame */
+	if (unlikely(xdp_frame_has_frags(xdpf)))
+		nr_frags = sinfo->nr_frags;
 
 	/* Part of headroom was reserved to xdpf */
 	headroom = sizeof(*xdpf) + xdpf->headroom;

@@ -582,6 +588,12 @@ struct sk_buff *__xdp_build_skb_from_frame(struct xdp_frame *xdpf,
 	if (xdpf->metasize)
 		skb_metadata_set(skb, xdpf->metasize);
 
+	if (unlikely(xdp_frame_has_frags(xdpf)))
+		xdp_update_skb_shared_info(skb, nr_frags,
+					   sinfo->xdp_frags_size,
+					   nr_frags * xdpf->frame_sz,
+					   xdp_frame_is_frag_pfmemalloc(xdpf));
+
 	/* Essential SKB info: protocol and skb->dev */
 	skb->protocol = eth_type_trans(skb, dev);

Signature · 1 line

2.34.1

Lorenzo Bianconi

author

2022-01-21 10:11 UTC #6 lore raw

PATCH v23 6/23 net: marvell: rely on xdp_update_skb_shared_info utility routine

Rely on xdp_update_skb_shared_info routine in order to avoid resetting frags array in skb_shared_info structure building the skb in mvneta_swbm_build_skb(). Frags array is expected to be initialized by the receiving driver building the xdp_buff and here we just need to update memory metadata.

Acked-by Toke Hoiland-Jorgensen <[email protected]>

---
 drivers/net/ethernet/marvell/mvneta.c | 23 ++++++++++-------------
 1 file changed, 10 insertions(+), 13 deletions(-)

drivers/net/ethernet/marvell/mvneta.c +10 ~~-13~~

index bc70292dda43..f1fd93e89c73 100644
@@ -2332,8 +2332,12 @@ mvneta_swbm_add_rx_fragment(struct mvneta_port *pp,
 		skb_frag_size_set(frag, data_len);
 		__skb_frag_set_page(frag, page);
 
-		if (!xdp_buff_has_frags(xdp))
+		if (!xdp_buff_has_frags(xdp)) {
+			sinfo->xdp_frags_size = *size;
 			xdp_buff_set_frags_flag(xdp);
+		}
+		if (page_is_pfmemalloc(page))
+			xdp_buff_set_frag_pfmemalloc(xdp);
 	} else {
 		page_pool_put_full_page(rxq->page_pool, page, true);
 	}

@@ -2347,7 +2351,6 @@ mvneta_swbm_build_skb(struct mvneta_port *pp, struct page_pool *pool,
 	struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp);
 	struct sk_buff *skb;
 	u8 num_frags;
-	int i;
 
 	if (unlikely(xdp_buff_has_frags(xdp)))
 		num_frags = sinfo->nr_frags;

@@ -2362,18 +2365,12 @@ mvneta_swbm_build_skb(struct mvneta_port *pp, struct page_pool *pool,
 	skb_put(skb, xdp->data_end - xdp->data);
 	skb->ip_summed = mvneta_rx_csum(pp, desc_status);
 
-	if (likely(!xdp_buff_has_frags(xdp)))
-		goto out;
-
-	for (i = 0; i < num_frags; i++) {
-		skb_frag_t *frag = &sinfo->frags[i];
-
-		skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags,
-				skb_frag_page(frag), skb_frag_off(frag),
-				skb_frag_size(frag), PAGE_SIZE);
-	}
+	if (unlikely(xdp_buff_has_frags(xdp)))
+		xdp_update_skb_shared_info(skb, num_frags,
+					   sinfo->xdp_frags_size,
+					   num_frags * xdp->frame_sz,
+					   xdp_buff_is_frag_pfmemalloc(xdp));
 
-out:
 	return skb;
 }

Signature · 1 line

2.34.1

Lorenzo Bianconi

author

2022-01-21 10:11 UTC #7 lore raw

PATCH v23 7/23 xdp: add frags support to xdp_return_{buff/frame}

Take into account if the received xdp_buff/xdp_frame is non-linear recycling/returning the frame memory to the allocator or into xdp_frame_bulk.

Acked-by Toke Hoiland-Jorgensen <[email protected]>

---
 include/net/xdp.h | 18 ++++++++++++++--
 net/core/xdp.c    | 54 ++++++++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 69 insertions(+), 3 deletions(-)

include/net/xdp.h +16 -2

index 1f8641ec658e..8463dea8b4db 100644
@@ -306,10 +306,24 @@ 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)
-		__xdp_release_frame(xdpf->data, mem);
+	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);
 }
 
 int xdp_rxq_info_reg(struct xdp_rxq_info *xdp_rxq,

net/core/xdp.c +53 -1

84 lines not on this page · raw message

Signature · 1 line

2.34.1

Lorenzo Bianconi

author

2022-01-21 10:11 UTC #8 lore raw

PATCH v23 8/23 net: mvneta: add frags support to XDP_TX

Introduce the capability to map non-linear xdp buffer running mvneta_xdp_submit_frame() for XDP_TX and XDP_REDIRECT

Acked-by Toke Hoiland-Jorgensen <[email protected]>

---
 drivers/net/ethernet/marvell/mvneta.c | 112 +++++++++++++++++---------
 1 file changed, 76 insertions(+), 36 deletions(-)

drivers/net/ethernet/marvell/mvneta.c +76 ~~-36~~

index f1fd93e89c73..c2248e23edcc 100644
@@ -1884,8 +1884,8 @@ static void mvneta_txq_bufs_free(struct mvneta_port *pp,
 			bytes_compl += buf->skb->len;
 			pkts_compl++;
 			dev_kfree_skb_any(buf->skb);
-		} else if (buf->type == MVNETA_TYPE_XDP_TX ||
-			   buf->type == MVNETA_TYPE_XDP_NDO) {
+		} else if ((buf->type == MVNETA_TYPE_XDP_TX ||
+			    buf->type == MVNETA_TYPE_XDP_NDO) && buf->xdpf) {
 			if (napi && buf->type == MVNETA_TYPE_XDP_TX)
 				xdp_return_frame_rx_napi(buf->xdpf);
 			else

@@ -2079,47 +2079,87 @@ mvneta_xdp_put_buff(struct mvneta_port *pp, struct mvneta_rx_queue *rxq,
 
 static int
 mvneta_xdp_submit_frame(struct mvneta_port *pp, struct mvneta_tx_queue *txq,
-			struct xdp_frame *xdpf, bool dma_map)
+			struct xdp_frame *xdpf, int *nxmit_byte, bool dma_map)
 {
-	struct mvneta_tx_desc *tx_desc;
-	struct mvneta_tx_buf *buf;
-	dma_addr_t dma_addr;
+	struct skb_shared_info *sinfo = xdp_get_shared_info_from_frame(xdpf);
+	struct device *dev = pp->dev->dev.parent;
+	struct mvneta_tx_desc *tx_desc = NULL;
+	int i, num_frames = 1;
+	struct page *page;
+
+	if (unlikely(xdp_frame_has_frags(xdpf)))
+		num_frames += sinfo->nr_frags;
 
-	if (txq->count >= txq->tx_stop_threshold)
+	if (txq->count + num_frames >= txq->size)
 		return MVNETA_XDP_DROPPED;
 
-	tx_desc = mvneta_txq_next_desc_get(txq);
+	for (i = 0; i < num_frames; i++) {
+		struct mvneta_tx_buf *buf = &txq->buf[txq->txq_put_index];
+		skb_frag_t *frag = NULL;
+		int len = xdpf->len;
+		dma_addr_t dma_addr;
 
-	buf = &txq->buf[txq->txq_put_index];
-	if (dma_map) {
-		/* ndo_xdp_xmit */
-		dma_addr = dma_map_single(pp->dev->dev.parent, xdpf->data,
-					  xdpf->len, DMA_TO_DEVICE);
-		if (dma_mapping_error(pp->dev->dev.parent, dma_addr)) {
-			mvneta_txq_desc_put(txq);
-			return MVNETA_XDP_DROPPED;
+		if (unlikely(i)) { /* paged area */
+			frag = &sinfo->frags[i - 1];
+			len = skb_frag_size(frag);
 		}
-		buf->type = MVNETA_TYPE_XDP_NDO;
-	} else {
-		struct page *page = virt_to_page(xdpf->data);
 
-		dma_addr = page_pool_get_dma_addr(page) +
-			   sizeof(*xdpf) + xdpf->headroom;
-		dma_sync_single_for_device(pp->dev->dev.parent, dma_addr,
-					   xdpf->len, DMA_BIDIRECTIONAL);
-		buf->type = MVNETA_TYPE_XDP_TX;
+		tx_desc = mvneta_txq_next_desc_get(txq);
+		if (dma_map) {
+			/* ndo_xdp_xmit */
+			void *data;
+
+			data = unlikely(frag) ? skb_frag_address(frag)
+					      : xdpf->data;
+			dma_addr = dma_map_single(dev, data, len,
+						  DMA_TO_DEVICE);
+			if (dma_mapping_error(dev, dma_addr)) {
+				mvneta_txq_desc_put(txq);
+				goto unmap;
+			}
+
+			buf->type = MVNETA_TYPE_XDP_NDO;
+		} else {
+			page = unlikely(frag) ? skb_frag_page(frag)
+					      : virt_to_page(xdpf->data);
+			dma_addr = page_pool_get_dma_addr(page);
+			if (unlikely(frag))
+				dma_addr += skb_frag_off(frag);
+			else
+				dma_addr += sizeof(*xdpf) + xdpf->headroom;
+			dma_sync_single_for_device(dev, dma_addr, len,
+						   DMA_BIDIRECTIONAL);
+			buf->type = MVNETA_TYPE_XDP_TX;
+		}
+		buf->xdpf = unlikely(i) ? NULL : xdpf;
+
+		tx_desc->command = unlikely(i) ? 0 : MVNETA_TXD_F_DESC;
+		tx_desc->buf_phys_addr = dma_addr;
+		tx_desc->data_size = len;
+		*nxmit_byte += len;
+
+		mvneta_txq_inc_put(txq);
 	}
-	buf->xdpf = xdpf;
 
-	tx_desc->command = MVNETA_TXD_FLZ_DESC;
-	tx_desc->buf_phys_addr = dma_addr;
-	tx_desc->data_size = xdpf->len;
+	/*last descriptor */
+	if (likely(tx_desc))
+		tx_desc->command |= MVNETA_TXD_L_DESC | MVNETA_TXD_Z_PAD;
 
-	mvneta_txq_inc_put(txq);
-	txq->pending++;
-	txq->count++;
+	txq->pending += num_frames;
+	txq->count += num_frames;
 
 	return MVNETA_XDP_TX;
+
+unmap:
+	for (i--; i >= 0; i--) {
+		mvneta_txq_desc_put(txq);
+		tx_desc = txq->descs + txq->next_desc_to_proc;
+		dma_unmap_single(dev, tx_desc->buf_phys_addr,
+				 tx_desc->data_size,
+				 DMA_TO_DEVICE);
+	}
+
+	return MVNETA_XDP_DROPPED;
 }
 
 static int

@@ -2128,8 +2168,8 @@ mvneta_xdp_xmit_back(struct mvneta_port *pp, struct xdp_buff *xdp)
 	struct mvneta_pcpu_stats *stats = this_cpu_ptr(pp->stats);
 	struct mvneta_tx_queue *txq;
 	struct netdev_queue *nq;
+	int cpu, nxmit_byte = 0;
 	struct xdp_frame *xdpf;
-	int cpu;
 	u32 ret;
 
 	xdpf = xdp_convert_buff_to_frame(xdp);

@@ -2141,10 +2181,10 @@ mvneta_xdp_xmit_back(struct mvneta_port *pp, struct xdp_buff *xdp)
 	nq = netdev_get_tx_queue(pp->dev, txq->id);
 
 	__netif_tx_lock(nq, cpu);
-	ret = mvneta_xdp_submit_frame(pp, txq, xdpf, false);
+	ret = mvneta_xdp_submit_frame(pp, txq, xdpf, &nxmit_byte, false);
 	if (ret == MVNETA_XDP_TX) {
 		u64_stats_update_begin(&stats->syncp);
-		stats->es.ps.tx_bytes += xdpf->len;
+		stats->es.ps.tx_bytes += nxmit_byte;
 		stats->es.ps.tx_packets++;
 		stats->es.ps.xdp_tx++;
 		u64_stats_update_end(&stats->syncp);

@@ -2183,11 +2223,11 @@ mvneta_xdp_xmit(struct net_device *dev, int num_frame,
 
 	__netif_tx_lock(nq, cpu);
 	for (i = 0; i < num_frame; i++) {
-		ret = mvneta_xdp_submit_frame(pp, txq, frames[i], true);
+		ret = mvneta_xdp_submit_frame(pp, txq, frames[i], &nxmit_byte,
+					      true);
 		if (ret != MVNETA_XDP_TX)
 			break;
 
-		nxmit_byte += frames[i]->len;
 		nxmit++;
 	}

Signature · 1 line

2.34.1

Lorenzo Bianconi

author

2022-01-21 10:11 UTC #9 lore raw

PATCH v23 9/23 bpf: introduce BPF_F_XDP_HAS_FRAGS flag in prog_flags loading the ebpf program

Introduce BPF_F_XDP_HAS_FRAGS and the related field in bpf_prog_aux in order to notify the driver the loaded program support xdp frags.

Acked-by Toke Hoiland-Jorgensen <[email protected]>

---
 include/linux/bpf.h            | 1 +
 include/uapi/linux/bpf.h       | 5 +++++
 kernel/bpf/syscall.c           | 4 +++-
 tools/include/uapi/linux/bpf.h | 5 +++++
 4 files changed, 14 insertions(+), 1 deletion(-)

include/linux/bpf.h +1 -0

index 80e3387ea3af..e93ed028a030 100644
@@ -933,6 +933,7 @@ struct bpf_prog_aux {
 	bool func_proto_unreliable;
 	bool sleepable;
 	bool tail_call_reachable;
+	bool xdp_has_frags;
 	struct hlist_node tramp_hlist;
 	/* BTF_KIND_FUNC_PROTO for valid attach_btf_id */
 	const struct btf_type *attach_func_proto;

include/uapi/linux/bpf.h +5 -0

index fe2272defcd9..945649c67e03 100644
@@ -1113,6 +1113,11 @@ enum bpf_link_type {
  */
 #define BPF_F_SLEEPABLE		(1U << 4)
 
+/* If BPF_F_XDP_HAS_FRAGS is used in BPF_PROG_LOAD command, the loaded program
+ * fully support xdp frags.
+ */
+#define BPF_F_XDP_HAS_FRAGS	(1U << 5)
+
 /* When BPF ldimm64's insn[0].src_reg != 0 then this can have
  * the following extensions:
  *

kernel/bpf/syscall.c +3 -1

index 9e0631f091a6..f29090643c6e 100644
@@ -2217,7 +2217,8 @@ static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr)
 				 BPF_F_ANY_ALIGNMENT |
 				 BPF_F_TEST_STATE_FREQ |
 				 BPF_F_SLEEPABLE |
-				 BPF_F_TEST_RND_HI32))
+				 BPF_F_TEST_RND_HI32 |
+				 BPF_F_XDP_HAS_FRAGS))
 		return -EINVAL;
 
 	if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) &&

@@ -2303,6 +2304,7 @@ static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr)
 	prog->aux->dst_prog = dst_prog;
 	prog->aux->offload_requested = !!attr->prog_ifindex;
 	prog->aux->sleepable = attr->prog_flags & BPF_F_SLEEPABLE;
+	prog->aux->xdp_has_frags = attr->prog_flags & BPF_F_XDP_HAS_FRAGS;
 
 	err = security_bpf_prog_alloc(prog->aux);
 	if (err)

tools/include/uapi/linux/bpf.h +5 -0

index fe2272defcd9..945649c67e03 100644
@@ -1113,6 +1113,11 @@ enum bpf_link_type {
  */
 #define BPF_F_SLEEPABLE		(1U << 4)
 
+/* If BPF_F_XDP_HAS_FRAGS is used in BPF_PROG_LOAD command, the loaded program
+ * fully support xdp frags.
+ */
+#define BPF_F_XDP_HAS_FRAGS	(1U << 5)
+
 /* When BPF ldimm64's insn[0].src_reg != 0 then this can have
  * the following extensions:
  *

Signature · 1 line

2.34.1

Lorenzo Bianconi

author

2022-01-21 10:11 UTC #10 lore raw

PATCH v23 10/23 net: mvneta: enable jumbo frames if the loaded XDP program support frags

Enable the capability to receive jumbo frames even if the interface is running in XDP mode if the loaded program declare to properly support xdp frags. At same time reject a xdp program not supporting xdp frags if the driver is running in xdp frags mode.

Acked-by Toke Hoiland-Jorgensen <[email protected]>

---
 drivers/net/ethernet/marvell/mvneta.c | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

drivers/net/ethernet/marvell/mvneta.c +9 -4

index c2248e23edcc..1ba49e464f36 100644
@@ -3778,6 +3778,7 @@ static void mvneta_percpu_disable(void *arg)
 static int mvneta_change_mtu(struct net_device *dev, int mtu)
 {
 	struct mvneta_port *pp = netdev_priv(dev);
+	struct bpf_prog *prog = pp->xdp_prog;
 	int ret;
 
 	if (!IS_ALIGNED(MVNETA_RX_PKT_SIZE(mtu), 8)) {

@@ -3786,8 +3787,11 @@ static int mvneta_change_mtu(struct net_device *dev, int mtu)
 		mtu = ALIGN(MVNETA_RX_PKT_SIZE(mtu), 8);
 	}
 
-	if (pp->xdp_prog && mtu > MVNETA_MAX_RX_BUF_SIZE) {
-		netdev_info(dev, "Illegal MTU value %d for XDP mode\n", mtu);
+	if (prog && !prog->aux->xdp_has_frags &&
+	    mtu > MVNETA_MAX_RX_BUF_SIZE) {
+		netdev_info(dev, "Illegal MTU %d for XDP prog without frags\n",
+			    mtu);
+
 		return -EINVAL;
 	}

@@ -4528,8 +4532,9 @@ static int mvneta_xdp_setup(struct net_device *dev, struct bpf_prog *prog,
 	struct mvneta_port *pp = netdev_priv(dev);
 	struct bpf_prog *old_prog;
 
-	if (prog && dev->mtu > MVNETA_MAX_RX_BUF_SIZE) {
-		NL_SET_ERR_MSG_MOD(extack, "MTU too large for XDP");
+	if (prog && !prog->aux->xdp_has_frags &&
+	    dev->mtu > MVNETA_MAX_RX_BUF_SIZE) {
+		NL_SET_ERR_MSG_MOD(extack, "prog does not support XDP frags");
 		return -EOPNOTSUPP;
 	}

Signature · 1 line

2.34.1

Lorenzo Bianconi

author

2022-01-21 10:11 UTC #11 lore raw

PATCH v23 11/23 bpf: introduce bpf_xdp_get_buff_len helper

Introduce bpf_xdp_get_buff_len helper in order to return the xdp buffer total size (linear and paged area)

Acked-by Toke Hoiland-Jorgensen <[email protected]>

---
 include/net/xdp.h              | 14 ++++++++++++++
 include/uapi/linux/bpf.h       |  7 +++++++
 net/core/filter.c              | 15 +++++++++++++++
 tools/include/uapi/linux/bpf.h |  7 +++++++
 4 files changed, 43 insertions(+)

include/net/xdp.h +14 -0

index 8463dea8b4db..52b593321956 100644
@@ -145,6 +145,20 @@ 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;

include/uapi/linux/bpf.h +7 -0

index 945649c67e03..5a28772063f6 100644
@@ -5054,6 +5054,12 @@ union bpf_attr {
  *		This helper is currently supported by cgroup programs only.
  *	Return
  *		0 on success, or a negative error in case of failure.
+ *
+ * u64 bpf_xdp_get_buff_len(struct xdp_buff *xdp_md)
+ *	Description
+ *		Get the total size of a given xdp buff (linear and paged area)
+ *	Return
+ *		The total size of a given xdp buffer.
  */
 #define __BPF_FUNC_MAPPER(FN)		\
 	FN(unspec),			\

@@ -5244,6 +5250,7 @@ union bpf_attr {
 	FN(get_func_arg_cnt),		\
 	FN(get_retval),			\
 	FN(set_retval),			\
+	FN(xdp_get_buff_len),		\
 	/* */
 
 /* integer value in 'imm' field of BPF_CALL instruction selects which helper

net/core/filter.c +15 -0

index f73a84c75970..a7f03bbca465 100644
@@ -3783,6 +3783,19 @@ static const struct bpf_func_proto sk_skb_change_head_proto = {
 	.arg2_type	= ARG_ANYTHING,
 	.arg3_type	= ARG_ANYTHING,
 };
+
+BPF_CALL_1(bpf_xdp_get_buff_len, struct  xdp_buff*, xdp)
+{
+	return xdp_get_buff_len(xdp);
+}
+
+static const struct bpf_func_proto bpf_xdp_get_buff_len_proto = {
+	.func		= bpf_xdp_get_buff_len,
+	.gpl_only	= false,
+	.ret_type	= RET_INTEGER,
+	.arg1_type	= ARG_PTR_TO_CTX,
+};
+
 static unsigned long xdp_get_metalen(const struct xdp_buff *xdp)
 {
 	return xdp_data_meta_unsupported(xdp) ? 0 :

@@ -7533,6 +7546,8 @@ xdp_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
 		return &bpf_xdp_redirect_map_proto;
 	case BPF_FUNC_xdp_adjust_tail:
 		return &bpf_xdp_adjust_tail_proto;
+	case BPF_FUNC_xdp_get_buff_len:
+		return &bpf_xdp_get_buff_len_proto;
 	case BPF_FUNC_fib_lookup:
 		return &bpf_xdp_fib_lookup_proto;
 	case BPF_FUNC_check_mtu:

tools/include/uapi/linux/bpf.h +7 -0

index 945649c67e03..5a28772063f6 100644
@@ -5054,6 +5054,12 @@ union bpf_attr {
  *		This helper is currently supported by cgroup programs only.
  *	Return
  *		0 on success, or a negative error in case of failure.
+ *
+ * u64 bpf_xdp_get_buff_len(struct xdp_buff *xdp_md)
+ *	Description
+ *		Get the total size of a given xdp buff (linear and paged area)
+ *	Return
+ *		The total size of a given xdp buffer.
  */
 #define __BPF_FUNC_MAPPER(FN)		\
 	FN(unspec),			\

@@ -5244,6 +5250,7 @@ union bpf_attr {
 	FN(get_func_arg_cnt),		\
 	FN(get_retval),			\
 	FN(set_retval),			\
+	FN(xdp_get_buff_len),		\
 	/* */
 
 /* integer value in 'imm' field of BPF_CALL instruction selects which helper

Signature · 1 line

2.34.1

Lorenzo Bianconi

author

2022-01-21 10:11 UTC #12 lore raw

PATCH v23 12/23 bpf: add frags support to the bpf_xdp_adjust_tail() API

From: Eelco Chaudron <[email protected]>

This change adds support for tail growing and shrinking for XDP frags.

When called on a non-linear packet with a grow request, it will work on the last fragment of the packet. So the maximum grow size is the last fragments tailroom, i.e. no new buffer will be allocated. A XDP frags capable driver is expected to set frag_size in xdp_rxq_info data structure to notify the XDP core the fragment size. frag_size set to 0 is interpreted by the XDP core as tail growing is not allowed.
Introduce __xdp_rxq_info_reg utility routine to initialize frag_size field.

When shrinking, it will work from the last fragment, all the way down to the base buffer depending on the shrinking size. It's important to mention that once you shrink down the fragment(s) are freed, so you can not grow again to the original size.

Acked-by Toke Hoiland-Jorgensen <[email protected]>

Acked-by Jakub Kicinski <[email protected]>

Co-developed-by Lorenzo Bianconi <[email protected]>

Signed-off-by Eelco Chaudron <[email protected]>

---
 drivers/net/ethernet/marvell/mvneta.c |  3 +-
 include/net/xdp.h                     | 16 ++++++-
 net/core/filter.c                     | 65 +++++++++++++++++++++++++++
 net/core/xdp.c                        | 12 ++---
 4 files changed, 88 insertions(+), 8 deletions(-)

drivers/net/ethernet/marvell/mvneta.c +2 -1

index 1ba49e464f36..309bd3e97ea0 100644
@@ -3298,7 +3298,8 @@ static int mvneta_create_page_pool(struct mvneta_port *pp,
 		return err;
 	}
 
-	err = xdp_rxq_info_reg(&rxq->xdp_rxq, pp->dev, rxq->id, 0);
+	err = __xdp_rxq_info_reg(&rxq->xdp_rxq, pp->dev, rxq->id, 0,
+				 PAGE_SIZE);
 	if (err < 0)
 		goto err_free_pp;

include/net/xdp.h +14 -2

index 52b593321956..b7721c3e4d1f 100644
@@ -60,6 +60,7 @@ struct xdp_rxq_info {
 	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 {

@@ -304,6 +305,8 @@ struct xdp_frame *xdp_convert_buff_to_frame(struct xdp_buff *xdp)
 	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);

@@ -340,8 +343,17 @@ static inline void xdp_release_frame(struct xdp_frame *xdpf)
 	__xdp_release_frame(xdpf->data, mem);
 }
 
-int xdp_rxq_info_reg(struct xdp_rxq_info *xdp_rxq,
-		     struct net_device *dev, u32 queue_index, unsigned int napi_id);
+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);

net/core/filter.c +65 -0

76 lines not on this page · raw message

net/core/xdp.c +7 -5

index a20bac565460..361df312ee7f 100644
@@ -162,8 +162,9 @@ static void xdp_rxq_info_init(struct xdp_rxq_info *xdp_rxq)
 }
 
 /* Returns 0 on success, negative on failure */
-int xdp_rxq_info_reg(struct xdp_rxq_info *xdp_rxq,
-		     struct net_device *dev, u32 queue_index, unsigned int napi_id)
+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)
 {
 	if (!dev) {
 		WARN(1, "Missing net_device from driver");

@@ -185,11 +186,12 @@ int xdp_rxq_info_reg(struct xdp_rxq_info *xdp_rxq,
 	xdp_rxq->dev = dev;
 	xdp_rxq->queue_index = queue_index;
 	xdp_rxq->napi_id = napi_id;
+	xdp_rxq->frag_size = frag_size;
 
 	xdp_rxq->reg_state = REG_STATE_REGISTERED;
 	return 0;
 }
-EXPORT_SYMBOL_GPL(xdp_rxq_info_reg);
+EXPORT_SYMBOL_GPL(__xdp_rxq_info_reg);
 
 void xdp_rxq_info_unused(struct xdp_rxq_info *xdp_rxq)
 {

@@ -369,8 +371,8 @@ EXPORT_SYMBOL_GPL(xdp_rxq_info_reg_mem_model);
  * is used for those calls sites.  Thus, allowing for faster recycling
  * of xdp_frames/pages in those cases.
  */
-static void __xdp_return(void *data, struct xdp_mem_info *mem, bool napi_direct,
-			 struct xdp_buff *xdp)
+void __xdp_return(void *data, struct xdp_mem_info *mem, bool napi_direct,
+		  struct xdp_buff *xdp)
 {
 	struct xdp_mem_allocator *xa;
 	struct page *page;

Signature · 1 line

2.34.1

Lorenzo Bianconi

author

2022-01-21 10:11 UTC #13 lore raw

PATCH v23 13/23 bpf: add frags support to xdp copy helpers

From: Eelco Chaudron <[email protected]>

This patch adds support for frags for the following helpers:
- bpf_xdp_output()
- bpf_perf_event_output()

Acked-by Toke Hoiland-Jorgensen <[email protected]>

Acked-by Jakub Kicinski <[email protected]>

Signed-off-by Eelco Chaudron <[email protected]>

---
 kernel/trace/bpf_trace.c                      |   3 +
 net/core/filter.c                             |  57 ++++++++-
 .../selftests/bpf/prog_tests/xdp_bpf2bpf.c    | 111 +++++++++++++-----
 .../selftests/bpf/progs/test_xdp_bpf2bpf.c    |   2 +-
 4 files changed, 137 insertions(+), 36 deletions(-)

kernel/trace/bpf_trace.c +3 -0

index 21aa30644219..06a9e220069e 100644
@@ -1562,6 +1562,7 @@ static const struct bpf_func_proto bpf_perf_event_output_proto_raw_tp = {
 
 extern const struct bpf_func_proto bpf_skb_output_proto;
 extern const struct bpf_func_proto bpf_xdp_output_proto;
+extern const struct bpf_func_proto bpf_xdp_get_buff_len_trace_proto;
 
 BPF_CALL_3(bpf_get_stackid_raw_tp, struct bpf_raw_tracepoint_args *, args,
 	   struct bpf_map *, map, u64, flags)

@@ -1661,6 +1662,8 @@ tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
 		return &bpf_sock_from_file_proto;
 	case BPF_FUNC_get_socket_cookie:
 		return &bpf_get_socket_ptr_cookie_proto;
+	case BPF_FUNC_xdp_get_buff_len:
+		return &bpf_xdp_get_buff_len_trace_proto;
 #endif
 	case BPF_FUNC_seq_printf:
 		return prog->expected_attach_type == BPF_TRACE_ITER ?

net/core/filter.c +52 -5

79 lines not on this page · raw message

tools/testing/selftests/bpf/prog_tests/xdp_bpf2bpf.c +81 ~~-30~~

141 lines not on this page · raw message

tools/testing/selftests/bpf/progs/test_xdp_bpf2bpf.c +1 -1

index 58cf4345f5cc..3379d303f41a 100644
@@ -49,7 +49,7 @@ int BPF_PROG(trace_on_entry, struct xdp_buff *xdp)
 	void *data = (void *)(long)xdp->data;
 
 	meta.ifindex = xdp->rxq->dev->ifindex;
-	meta.pkt_len = data_end - data;
+	meta.pkt_len = bpf_xdp_get_buff_len((struct xdp_md *)xdp);
 	bpf_xdp_output(xdp, &perf_buf_map,
 		       ((__u64) meta.pkt_len << 32) |
 		       BPF_F_CURRENT_CPU,

Signature · 1 line

2.34.1

Lorenzo Bianconi

author

2022-01-21 10:11 UTC #14 lore raw

PATCH v23 14/23 bpf: move user_size out of bpf_test_init

Rely on data_size_in in bpf_test_init routine signature. This is a preliminary patch to introduce xdp frags selftest

Acked-by Toke Hoiland-Jorgensen <[email protected]>

---
 net/bpf/test_run.c | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

net/bpf/test_run.c +7 -6

index 3a5bf8ad834d..67f7c7d75944 100644
@@ -367,11 +367,10 @@ BTF_SET_START(test_sk_ret_null_kfunc_ids)
 BTF_ID(func, bpf_kfunc_call_test_acquire)
 BTF_SET_END(test_sk_ret_null_kfunc_ids)
 
-static void *bpf_test_init(const union bpf_attr *kattr, u32 size,
-			   u32 headroom, u32 tailroom)
+static void *bpf_test_init(const union bpf_attr *kattr, u32 user_size,
+			   u32 size, u32 headroom, u32 tailroom)
 {
 	void __user *data_in = u64_to_user_ptr(kattr->test.data_in);
-	u32 user_size = kattr->test.data_size_in;
 	void *data;
 
 	if (size < ETH_HLEN || size > PAGE_SIZE - headroom - tailroom)

@@ -699,7 +698,8 @@ int bpf_prog_test_run_skb(struct bpf_prog *prog, const union bpf_attr *kattr,
 	if (kattr->test.flags || kattr->test.cpu)
 		return -EINVAL;
 
-	data = bpf_test_init(kattr, size, NET_SKB_PAD + NET_IP_ALIGN,
+	data = bpf_test_init(kattr, kattr->test.data_size_in,
+			     size, NET_SKB_PAD + NET_IP_ALIGN,
 			     SKB_DATA_ALIGN(sizeof(struct skb_shared_info)));
 	if (IS_ERR(data))
 		return PTR_ERR(data);

@@ -908,7 +908,8 @@ int bpf_prog_test_run_xdp(struct bpf_prog *prog, const union bpf_attr *kattr,
 	/* XDP have extra tailroom as (most) drivers use full page */
 	max_data_sz = 4096 - headroom - tailroom;
 
-	data = bpf_test_init(kattr, max_data_sz, headroom, tailroom);
+	data = bpf_test_init(kattr, kattr->test.data_size_in,
+			     max_data_sz, headroom, tailroom);
 	if (IS_ERR(data)) {
 		ret = PTR_ERR(data);
 		goto free_ctx;

@@ -994,7 +995,7 @@ int bpf_prog_test_run_flow_dissector(struct bpf_prog *prog,
 	if (size < ETH_HLEN)
 		return -EINVAL;
 
-	data = bpf_test_init(kattr, size, 0, 0);
+	data = bpf_test_init(kattr, kattr->test.data_size_in, size, 0, 0);
 	if (IS_ERR(data))
 		return PTR_ERR(data);

Signature · 1 line

2.34.1

Lorenzo Bianconi

author

2022-01-21 10:11 UTC #15 lore raw

PATCH v23 15/23 bpf: introduce frags support to bpf_prog_test_run_xdp()

Introduce the capability to allocate a xdp frags in bpf_prog_test_run_xdp routine. This is a preliminary patch to introduce the selftests for new xdp frags ebpf helpers

Acked-by Toke Hoiland-Jorgensen <[email protected]>

---
 net/bpf/test_run.c | 58 +++++++++++++++++++++++++++++++++++-----------
 1 file changed, 45 insertions(+), 13 deletions(-)

net/bpf/test_run.c +45 ~~-13~~

index 67f7c7d75944..394dd489b8f5 100644
@@ -876,16 +876,16 @@ int bpf_prog_test_run_xdp(struct bpf_prog *prog, const union bpf_attr *kattr,
 			  union bpf_attr __user *uattr)
 {
 	u32 tailroom = SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
-	u32 headroom = XDP_PACKET_HEADROOM;
 	u32 size = kattr->test.data_size_in;
+	u32 headroom = XDP_PACKET_HEADROOM;
+	u32 retval, duration, max_data_sz;
 	u32 repeat = kattr->test.repeat;
 	struct netdev_rx_queue *rxqueue;
+	struct skb_shared_info *sinfo;
 	struct xdp_buff xdp = {};
-	u32 retval, duration;
+	int i, ret = -EINVAL;
 	struct xdp_md *ctx;
-	u32 max_data_sz;
 	void *data;
-	int ret = -EINVAL;
 
 	if (prog->expected_attach_type == BPF_XDP_DEVMAP ||
 	    prog->expected_attach_type == BPF_XDP_CPUMAP)

@@ -905,27 +905,60 @@ int bpf_prog_test_run_xdp(struct bpf_prog *prog, const union bpf_attr *kattr,
 		headroom -= ctx->data;
 	}
 
-	/* XDP have extra tailroom as (most) drivers use full page */
 	max_data_sz = 4096 - headroom - tailroom;
+	size = min_t(u32, size, max_data_sz);
 
-	data = bpf_test_init(kattr, kattr->test.data_size_in,
-			     max_data_sz, headroom, tailroom);
+	data = bpf_test_init(kattr, size, max_data_sz, headroom, tailroom);
 	if (IS_ERR(data)) {
 		ret = PTR_ERR(data);
 		goto free_ctx;
 	}
 
 	rxqueue = __netif_get_rx_queue(current->nsproxy->net_ns->loopback_dev, 0);
-	xdp_init_buff(&xdp, headroom + max_data_sz + tailroom,
-		      &rxqueue->xdp_rxq);
+	rxqueue->xdp_rxq.frag_size = headroom + max_data_sz + tailroom;
+	xdp_init_buff(&xdp, rxqueue->xdp_rxq.frag_size, &rxqueue->xdp_rxq);
 	xdp_prepare_buff(&xdp, data, headroom, size, true);
+	sinfo = xdp_get_shared_info_from_buff(&xdp);
 
 	ret = xdp_convert_md_to_buff(ctx, &xdp);
 	if (ret)
 		goto free_data;
 
+	if (unlikely(kattr->test.data_size_in > size)) {
+		void __user *data_in = u64_to_user_ptr(kattr->test.data_in);
+
+		while (size < kattr->test.data_size_in) {
+			struct page *page;
+			skb_frag_t *frag;
+			int data_len;
+
+			page = alloc_page(GFP_KERNEL);
+			if (!page) {
+				ret = -ENOMEM;
+				goto out;
+			}
+
+			frag = &sinfo->frags[sinfo->nr_frags++];
+			__skb_frag_set_page(frag, page);
+
+			data_len = min_t(int, kattr->test.data_size_in - size,
+					 PAGE_SIZE);
+			skb_frag_size_set(frag, data_len);
+
+			if (copy_from_user(page_address(page), data_in + size,
+					   data_len)) {
+				ret = -EFAULT;
+				goto out;
+			}
+			sinfo->xdp_frags_size += data_len;
+			size += data_len;
+		}
+		xdp_buff_set_frags_flag(&xdp);
+	}
+
 	if (repeat > 1)
 		bpf_prog_change_xdp(NULL, prog);
+
 	ret = bpf_test_run(prog, &xdp, repeat, &retval, &duration, true);
 	/* We convert the xdp_buff back to an xdp_md before checking the return
 	 * code so the reference count of any held netdevice will be decremented

@@ -935,10 +968,7 @@ int bpf_prog_test_run_xdp(struct bpf_prog *prog, const union bpf_attr *kattr,
 	if (ret)
 		goto out;
 
-	if (xdp.data_meta != data + headroom ||
-	    xdp.data_end != xdp.data_meta + size)
-		size = xdp.data_end - xdp.data_meta;
-
+	size = xdp.data_end - xdp.data_meta + sinfo->xdp_frags_size;
 	ret = bpf_test_finish(kattr, uattr, xdp.data_meta, size, retval,
 			      duration);
 	if (!ret)

@@ -949,6 +979,8 @@ int bpf_prog_test_run_xdp(struct bpf_prog *prog, const union bpf_attr *kattr,
 	if (repeat > 1)
 		bpf_prog_change_xdp(prog, NULL);
 free_data:
+	for (i = 0; i < sinfo->nr_frags; i++)
+		__free_page(skb_frag_page(&sinfo->frags[i]));
 	kfree(data);
 free_ctx:
 	kfree(ctx);

Signature · 1 line

2.34.1

Lorenzo Bianconi

author

2022-01-21 10:11 UTC #16 lore raw

PATCH v23 16/23 bpf: test_run: add xdp_shared_info pointer in bpf_test_finish signature

introduce xdp_shared_info pointer in bpf_test_finish signature in order to copy back paged data from a xdp frags frame to userspace buffer

Acked-by Toke Hoiland-Jorgensen <[email protected]>

---
 net/bpf/test_run.c | 48 +++++++++++++++++++++++++++++++++++++---------
 1 file changed, 39 insertions(+), 9 deletions(-)

net/bpf/test_run.c +39 -9

index 394dd489b8f5..541933abd16f 100644
@@ -131,7 +131,8 @@ static int bpf_test_run(struct bpf_prog *prog, void *ctx, u32 repeat,
 
 static int bpf_test_finish(const union bpf_attr *kattr,
 			   union bpf_attr __user *uattr, const void *data,
-			   u32 size, u32 retval, u32 duration)
+			   struct skb_shared_info *sinfo, u32 size,
+			   u32 retval, u32 duration)
 {
 	void __user *data_out = u64_to_user_ptr(kattr->test.data_out);
 	int err = -EFAULT;

@@ -146,8 +147,36 @@ static int bpf_test_finish(const union bpf_attr *kattr,
 		err = -ENOSPC;
 	}
 
-	if (data_out && copy_to_user(data_out, data, copy_size))
-		goto out;
+	if (data_out) {
+		int len = sinfo ? copy_size - sinfo->xdp_frags_size : copy_size;
+
+		if (copy_to_user(data_out, data, len))
+			goto out;
+
+		if (sinfo) {
+			int i, offset = len, data_len;
+
+			for (i = 0; i < sinfo->nr_frags; i++) {
+				skb_frag_t *frag = &sinfo->frags[i];
+
+				if (offset >= copy_size) {
+					err = -ENOSPC;
+					break;
+				}
+
+				data_len = min_t(int, copy_size - offset,
+						 skb_frag_size(frag));
+
+				if (copy_to_user(data_out + offset,
+						 skb_frag_address(frag),
+						 data_len))
+					goto out;
+
+				offset += data_len;
+			}
+		}
+	}
+
 	if (copy_to_user(&uattr->test.data_size_out, &size, sizeof(size)))
 		goto out;
 	if (copy_to_user(&uattr->test.retval, &retval, sizeof(retval)))

@@ -801,7 +830,8 @@ int bpf_prog_test_run_skb(struct bpf_prog *prog, const union bpf_attr *kattr,
 	/* bpf program can never convert linear skb to non-linear */
 	if (WARN_ON_ONCE(skb_is_nonlinear(skb)))
 		size = skb_headlen(skb);
-	ret = bpf_test_finish(kattr, uattr, skb->data, size, retval, duration);
+	ret = bpf_test_finish(kattr, uattr, skb->data, NULL, size, retval,
+			      duration);
 	if (!ret)
 		ret = bpf_ctx_finish(kattr, uattr, ctx,
 				     sizeof(struct __sk_buff));

@@ -969,8 +999,8 @@ int bpf_prog_test_run_xdp(struct bpf_prog *prog, const union bpf_attr *kattr,
 		goto out;
 
 	size = xdp.data_end - xdp.data_meta + sinfo->xdp_frags_size;
-	ret = bpf_test_finish(kattr, uattr, xdp.data_meta, size, retval,
-			      duration);
+	ret = bpf_test_finish(kattr, uattr, xdp.data_meta, sinfo, size,
+			      retval, duration);
 	if (!ret)
 		ret = bpf_ctx_finish(kattr, uattr, ctx,
 				     sizeof(struct xdp_md));

@@ -1062,8 +1092,8 @@ int bpf_prog_test_run_flow_dissector(struct bpf_prog *prog,
 	if (ret < 0)
 		goto out;
 
-	ret = bpf_test_finish(kattr, uattr, &flow_keys, sizeof(flow_keys),
-			      retval, duration);
+	ret = bpf_test_finish(kattr, uattr, &flow_keys, NULL,
+			      sizeof(flow_keys), retval, duration);
 	if (!ret)
 		ret = bpf_ctx_finish(kattr, uattr, user_ctx,
 				     sizeof(struct bpf_flow_keys));

@@ -1167,7 +1197,7 @@ int bpf_prog_test_run_sk_lookup(struct bpf_prog *prog, const union bpf_attr *kat
 		user_ctx->cookie = sock_gen_cookie(ctx.selected_sk);
 	}
 
-	ret = bpf_test_finish(kattr, uattr, NULL, 0, retval, duration);
+	ret = bpf_test_finish(kattr, uattr, NULL, NULL, 0, retval, duration);
 	if (!ret)
 		ret = bpf_ctx_finish(kattr, uattr, user_ctx, sizeof(*user_ctx));

Signature · 1 line

2.34.1

Lorenzo Bianconi

author

2022-01-21 10:12 UTC #17 lore raw

PATCH v23 17/23 bpf: selftests: update xdp_adjust_tail selftest to include xdp frags

From: Eelco Chaudron <[email protected]>

This change adds test cases for the xdp frags scenarios when shrinking and growing.

Acked-by Toke Hoiland-Jorgensen <[email protected]>

Co-developed-by Lorenzo Bianconi <[email protected]>

Signed-off-by Eelco Chaudron <[email protected]>

---
 .../bpf/prog_tests/xdp_adjust_tail.c          | 125 ++++++++++++++++++
 .../bpf/progs/test_xdp_adjust_tail_grow.c     |  10 +-
 .../bpf/progs/test_xdp_adjust_tail_shrink.c   |  32 ++++-
 3 files changed, 160 insertions(+), 7 deletions(-)

tools/testing/selftests/bpf/prog_tests/xdp_adjust_tail.c +125 -0

index d5ebe92b0ebb..ccc9e63254a8 100644
@@ -118,6 +118,127 @@ static void test_xdp_adjust_tail_grow2(void)
 	bpf_object__close(obj);
 }
 
+void test_xdp_adjust_frags_tail_shrink(void)
+{
+	const char *file = "./test_xdp_adjust_tail_shrink.o";
+	__u32 duration, retval, size, exp_size;
+	struct bpf_program *prog;
+	struct bpf_object *obj;
+	int err, prog_fd;
+	__u8 *buf;
+
+	/* For the individual test cases, the first byte in the packet
+	 * indicates which test will be run.
+	 */
+	obj = bpf_object__open(file);
+	if (libbpf_get_error(obj))
+		return;
+
+	prog = bpf_object__next_program(obj, NULL);
+	if (bpf_object__load(obj))
+		return;
+
+	prog_fd = bpf_program__fd(prog);
+
+	buf = malloc(9000);
+	if (!ASSERT_OK_PTR(buf, "alloc buf 9Kb"))
+		goto out;
+
+	memset(buf, 0, 9000);
+
+	/* Test case removing 10 bytes from last frag, NOT freeing it */
+	exp_size = 8990; /* 9000 - 10 */
+	err = bpf_prog_test_run(prog_fd, 1, buf, 9000,
+				buf, &size, &retval, &duration);
+
+	ASSERT_OK(err, "9Kb-10b");
+	ASSERT_EQ(retval, XDP_TX, "9Kb-10b retval");
+	ASSERT_EQ(size, exp_size, "9Kb-10b size");
+
+	/* Test case removing one of two pages, assuming 4K pages */
+	buf[0] = 1;
+	exp_size = 4900; /* 9000 - 4100 */
+	err = bpf_prog_test_run(prog_fd, 1, buf, 9000,
+				buf, &size, &retval, &duration);
+
+	ASSERT_OK(err, "9Kb-4Kb");
+	ASSERT_EQ(retval, XDP_TX, "9Kb-4Kb retval");
+	ASSERT_EQ(size, exp_size, "9Kb-4Kb size");
+
+	/* Test case removing two pages resulting in a linear xdp_buff */
+	buf[0] = 2;
+	exp_size = 800; /* 9000 - 8200 */
+	err = bpf_prog_test_run(prog_fd, 1, buf, 9000,
+				buf, &size, &retval, &duration);
+
+	ASSERT_OK(err, "9Kb-9Kb");
+	ASSERT_EQ(retval, XDP_TX, "9Kb-9Kb retval");
+	ASSERT_EQ(size, exp_size, "9Kb-9Kb size");
+
+	free(buf);
+out:
+	bpf_object__close(obj);
+}
+
+void test_xdp_adjust_frags_tail_grow(void)
+{
+	const char *file = "./test_xdp_adjust_tail_grow.o";
+	__u32 duration, retval, size, exp_size;
+	struct bpf_program *prog;
+	struct bpf_object *obj;
+	int err, i, prog_fd;
+	__u8 *buf;
+
+	obj = bpf_object__open(file);
+	if (libbpf_get_error(obj))
+		return;
+
+	prog = bpf_object__next_program(obj, NULL);
+	if (bpf_object__load(obj))
+		return;
+
+	prog_fd = bpf_program__fd(prog);
+
+	buf = malloc(16384);
+	if (!ASSERT_OK_PTR(buf, "alloc buf 16Kb"))
+		goto out;
+
+	/* Test case add 10 bytes to last frag */
+	memset(buf, 1, 16384);
+	size = 9000;
+	exp_size = size + 10;
+	err = bpf_prog_test_run(prog_fd, 1, buf, size,
+				buf, &size, &retval, &duration);
+
+	ASSERT_OK(err, "9Kb+10b");
+	ASSERT_EQ(retval, XDP_TX, "9Kb+10b retval");
+	ASSERT_EQ(size, exp_size, "9Kb+10b size");
+
+	for (i = 0; i < 9000; i++)
+		ASSERT_EQ(buf[i], 1, "9Kb+10b-old");
+
+	for (i = 9000; i < 9010; i++)
+		ASSERT_EQ(buf[i], 0, "9Kb+10b-new");
+
+	for (i = 9010; i < 16384; i++)
+		ASSERT_EQ(buf[i], 1, "9Kb+10b-untouched");
+
+	/* Test a too large grow */
+	memset(buf, 1, 16384);
+	size = 9001;
+	exp_size = size;
+	err = bpf_prog_test_run(prog_fd, 1, buf, size,
+				buf, &size, &retval, &duration);
+
+	ASSERT_OK(err, "9Kb+10b");
+	ASSERT_EQ(retval, XDP_DROP, "9Kb+10b retval");
+	ASSERT_EQ(size, exp_size, "9Kb+10b size");
+
+	free(buf);
+out:
+	bpf_object__close(obj);
+}
+
 void test_xdp_adjust_tail(void)
 {
 	if (test__start_subtest("xdp_adjust_tail_shrink"))

@@ -126,4 +247,8 @@ void test_xdp_adjust_tail(void)
 		test_xdp_adjust_tail_grow();
 	if (test__start_subtest("xdp_adjust_tail_grow2"))
 		test_xdp_adjust_tail_grow2();
+	if (test__start_subtest("xdp_adjust_frags_tail_shrink"))
+		test_xdp_adjust_frags_tail_shrink();
+	if (test__start_subtest("xdp_adjust_frags_tail_grow"))
+		test_xdp_adjust_frags_tail_grow();
 }

tools/testing/selftests/bpf/progs/test_xdp_adjust_tail_grow.c +7 -3

index 199c61b7d062..53b64c999450 100644
@@ -7,11 +7,10 @@ int _xdp_adjust_tail_grow(struct xdp_md *xdp)
 {
 	void *data_end = (void *)(long)xdp->data_end;
 	void *data = (void *)(long)xdp->data;
-	unsigned int data_len;
+	int data_len = bpf_xdp_get_buff_len(xdp);
 	int offset = 0;
 
 	/* Data length determine test case */
-	data_len = data_end - data;
 
 	if (data_len == 54) { /* sizeof(pkt_v4) */
 		offset = 4096; /* test too large offset */

@@ -20,7 +19,12 @@ int _xdp_adjust_tail_grow(struct xdp_md *xdp)
 	} else if (data_len == 64) {
 		offset = 128;
 	} else if (data_len == 128) {
-		offset = 4096 - 256 - 320 - data_len; /* Max tail grow 3520 */
+		/* Max tail grow 3520 */
+		offset = 4096 - 256 - 320 - data_len;
+	} else if (data_len == 9000) {
+		offset = 10;
+	} else if (data_len == 9001) {
+		offset = 4096;
 	} else {
 		return XDP_ABORTED; /* No matching test */
 	}

tools/testing/selftests/bpf/progs/test_xdp_adjust_tail_shrink.c +28 -4

index b7448253d135..ca68c038357c 100644
@@ -12,14 +12,38 @@
 SEC("xdp")
 int _xdp_adjust_tail_shrink(struct xdp_md *xdp)
 {
-	void *data_end = (void *)(long)xdp->data_end;
-	void *data = (void *)(long)xdp->data;
+	__u8 *data_end = (void *)(long)xdp->data_end;
+	__u8 *data = (void *)(long)xdp->data;
 	int offset = 0;
 
-	if (data_end - data == 54) /* sizeof(pkt_v4) */
+	switch (bpf_xdp_get_buff_len(xdp)) {
+	case 54:
+		/* sizeof(pkt_v4) */
 		offset = 256; /* shrink too much */
-	else
+		break;
+	case 9000:
+		/* non-linear buff test cases */
+		if (data + 1 > data_end)
+			return XDP_DROP;
+
+		switch (data[0]) {
+		case 0:
+			offset = 10;
+			break;
+		case 1:
+			offset = 4100;
+			break;
+		case 2:
+			offset = 8200;
+			break;
+		default:
+			return XDP_DROP;
+		}
+		break;
+	default:
 		offset = 20;
+		break;
+	}
 	if (bpf_xdp_adjust_tail(xdp, 0 - offset))
 		return XDP_DROP;
 	return XDP_TX;

Signature · 1 line

2.34.1

Lorenzo Bianconi

author

2022-01-21 10:12 UTC #18 lore raw

PATCH v23 18/23 libbpf: Add SEC name for xdp frags programs

Introduce support for the following SEC entries for XDP frags property:
- SEC("xdp.frags")
- SEC("xdp.frags/devmap")
- SEC("xdp.frags/cpumap")

Acked-by Toke Hoiland-Jorgensen <[email protected]>

---
 tools/lib/bpf/libbpf.c | 8 ++++++++
 1 file changed, 8 insertions(+)

tools/lib/bpf/libbpf.c +8 -0

index fc6d530e20db..a8c750373ad5 100644
@@ -235,6 +235,8 @@ enum sec_def_flags {
 	SEC_SLEEPABLE = 8,
 	/* allow non-strict prefix matching */
 	SEC_SLOPPY_PFX = 16,
+	/* BPF program support non-linear XDP buffer */
+	SEC_XDP_FRAGS = 32,
 };
 
 struct bpf_sec_def {

@@ -6570,6 +6572,9 @@ static int libbpf_preload_prog(struct bpf_program *prog,
 	if (def & SEC_SLEEPABLE)
 		opts->prog_flags |= BPF_F_SLEEPABLE;
 
+	if (prog->type == BPF_PROG_TYPE_XDP && (def & SEC_XDP_FRAGS))
+		opts->prog_flags |= BPF_F_XDP_HAS_FRAGS;
+
 	if ((prog->type == BPF_PROG_TYPE_TRACING ||
 	     prog->type == BPF_PROG_TYPE_LSM ||
 	     prog->type == BPF_PROG_TYPE_EXT) && !prog->attach_btf_id) {

@@ -8608,8 +8613,11 @@ static const struct bpf_sec_def section_defs[] = {
 	SEC_DEF("lsm.s/",		LSM, BPF_LSM_MAC, SEC_ATTACH_BTF | SEC_SLEEPABLE, attach_lsm),
 	SEC_DEF("iter/",		TRACING, BPF_TRACE_ITER, SEC_ATTACH_BTF, attach_iter),
 	SEC_DEF("syscall",		SYSCALL, 0, SEC_SLEEPABLE),
+	SEC_DEF("xdp.frags/devmap",	XDP, BPF_XDP_DEVMAP, SEC_XDP_FRAGS),
 	SEC_DEF("xdp_devmap/",		XDP, BPF_XDP_DEVMAP, SEC_ATTACHABLE),
+	SEC_DEF("xdp.frags/cpumap",	XDP, BPF_XDP_CPUMAP, SEC_XDP_FRAGS),
 	SEC_DEF("xdp_cpumap/",		XDP, BPF_XDP_CPUMAP, SEC_ATTACHABLE),
+	SEC_DEF("xdp.frags",		XDP, BPF_XDP, SEC_XDP_FRAGS),
 	SEC_DEF("xdp",			XDP, BPF_XDP, SEC_ATTACHABLE_OPT | SEC_SLOPPY_PFX),
 	SEC_DEF("perf_event",		PERF_EVENT, 0, SEC_NONE | SEC_SLOPPY_PFX),
 	SEC_DEF("lwt_in",		LWT_IN, 0, SEC_NONE | SEC_SLOPPY_PFX),

Signature · 1 line

2.34.1

Lorenzo Bianconi

author

2022-01-21 10:12 UTC #19 lore raw

PATCH v23 19/23 bpf: generalise tail call map compatibility check

From: Toke Hoiland-Jorgensen <[email protected]>

The check for tail call map compatibility ensures that tail calls only happen between maps of the same type. To ensure backwards compatibility for XDP frags we need a similar type of check for cpumap and devmap programs, so move the state from bpf_array_aux into bpf_map, add xdp_has_frags to the check, and apply the same check to cpumap and devmap.

Co-developed-by Lorenzo Bianconi <[email protected]>

Signed-off-by Toke Hoiland-Jorgensen <[email protected]>

---
 include/linux/bpf.h   | 30 +++++++++++++++++++-----------
 kernel/bpf/arraymap.c |  4 +---
 kernel/bpf/core.c     | 28 ++++++++++++++--------------
 kernel/bpf/cpumap.c   |  8 +++++---
 kernel/bpf/devmap.c   |  3 ++-
 kernel/bpf/syscall.c  | 15 +++++++--------
 6 files changed, 48 insertions(+), 40 deletions(-)

include/linux/bpf.h +19 ~~-11~~

index e93ed028a030..e8ec8d2f2fe3 100644
@@ -194,6 +194,17 @@ struct bpf_map {
 	struct work_struct work;
 	struct mutex freeze_mutex;
 	atomic64_t writecnt;
+	/* 'Ownership' of program-containing map is claimed by the first program
+	 * that is going to use this map or by the first program which FD is
+	 * stored in the map to make sure that all callers and callees have the
+	 * same prog type, JITed flag and xdp_has_frags flag.
+	 */
+	struct {
+		spinlock_t lock;
+		enum bpf_prog_type type;
+		bool jited;
+		bool xdp_has_frags;
+	} owner;
 };
 
 static inline bool map_value_has_spin_lock(const struct bpf_map *map)

@@ -994,16 +1005,6 @@ struct bpf_prog_aux {
 };
 
 struct bpf_array_aux {
-	/* 'Ownership' of prog array is claimed by the first program that
-	 * is going to use this map or by the first program which FD is
-	 * stored in the map to make sure that all callers and callees have
-	 * the same prog type and JITed flag.
-	 */
-	struct {
-		spinlock_t lock;
-		enum bpf_prog_type type;
-		bool jited;
-	} owner;
 	/* Programs with direct jumps into programs part of this array. */
 	struct list_head poke_progs;
 	struct bpf_map *map;

@@ -1178,7 +1179,14 @@ struct bpf_event_entry {
 	struct rcu_head rcu;
 };
 
-bool bpf_prog_array_compatible(struct bpf_array *array, const struct bpf_prog *fp);
+static inline bool map_type_contains_progs(struct bpf_map *map)
+{
+	return map->map_type == BPF_MAP_TYPE_PROG_ARRAY ||
+	       map->map_type == BPF_MAP_TYPE_DEVMAP ||
+	       map->map_type == BPF_MAP_TYPE_CPUMAP;
+}
+
+bool bpf_prog_map_compatible(struct bpf_map *map, const struct bpf_prog *fp);
 int bpf_prog_calc_tag(struct bpf_prog *fp);
 
 const struct bpf_func_proto *bpf_get_trace_printk_proto(void);

kernel/bpf/arraymap.c +1 -3

index c7a5be3bf8be..7f145aefbff8 100644
@@ -837,13 +837,12 @@ static int fd_array_map_delete_elem(struct bpf_map *map, void *key)
 static void *prog_fd_array_get_ptr(struct bpf_map *map,
 				   struct file *map_file, int fd)
 {
-	struct bpf_array *array = container_of(map, struct bpf_array, map);
 	struct bpf_prog *prog = bpf_prog_get(fd);
 
 	if (IS_ERR(prog))
 		return prog;
 
-	if (!bpf_prog_array_compatible(array, prog)) {
+	if (!bpf_prog_map_compatible(map, prog)) {
 		bpf_prog_put(prog);
 		return ERR_PTR(-EINVAL);
 	}

@@ -1071,7 +1070,6 @@ static struct bpf_map *prog_array_map_alloc(union bpf_attr *attr)
 	INIT_WORK(&aux->work, prog_array_map_clear_deferred);
 	INIT_LIST_HEAD(&aux->poke_progs);
 	mutex_init(&aux->poke_mutex);
-	spin_lock_init(&aux->owner.lock);
 
 	map = array_map_alloc(attr);
 	if (IS_ERR(map)) {

kernel/bpf/core.c +14 ~~-14~~

index de3e5bc6781f..0a1cfd8544b9 100644
@@ -1829,28 +1829,30 @@ static unsigned int __bpf_prog_ret0_warn(const void *ctx,
 }
 #endif
 
-bool bpf_prog_array_compatible(struct bpf_array *array,
-			       const struct bpf_prog *fp)
+bool bpf_prog_map_compatible(struct bpf_map *map,
+			     const struct bpf_prog *fp)
 {
 	bool ret;
 
 	if (fp->kprobe_override)
 		return false;
 
-	spin_lock(&array->aux->owner.lock);
-
-	if (!array->aux->owner.type) {
+	spin_lock(&map->owner.lock);
+	if (!map->owner.type) {
 		/* There's no owner yet where we could check for
 		 * compatibility.
 		 */
-		array->aux->owner.type  = fp->type;
-		array->aux->owner.jited = fp->jited;
+		map->owner.type  = fp->type;
+		map->owner.jited = fp->jited;
+		map->owner.xdp_has_frags = fp->aux->xdp_has_frags;
 		ret = true;
 	} else {
-		ret = array->aux->owner.type  == fp->type &&
-		      array->aux->owner.jited == fp->jited;
+		ret = map->owner.type  == fp->type &&
+		      map->owner.jited == fp->jited &&
+		      map->owner.xdp_has_frags == fp->aux->xdp_has_frags;
 	}
-	spin_unlock(&array->aux->owner.lock);
+	spin_unlock(&map->owner.lock);
+
 	return ret;
 }

@@ -1862,13 +1864,11 @@ static int bpf_check_tail_call(const struct bpf_prog *fp)
 	mutex_lock(&aux->used_maps_mutex);
 	for (i = 0; i < aux->used_map_cnt; i++) {
 		struct bpf_map *map = aux->used_maps[i];
-		struct bpf_array *array;
 
-		if (map->map_type != BPF_MAP_TYPE_PROG_ARRAY)
+		if (!map_type_contains_progs(map))
 			continue;
 
-		array = container_of(map, struct bpf_array, map);
-		if (!bpf_prog_array_compatible(array, fp)) {
+		if (!bpf_prog_map_compatible(map, fp)) {
 			ret = -EINVAL;
 			goto out;
 		}

kernel/bpf/cpumap.c +5 -3

index b3e6b9422238..650e5d21f90d 100644
@@ -397,7 +397,8 @@ static int cpu_map_kthread_run(void *data)
 	return 0;
 }
 
-static int __cpu_map_load_bpf_program(struct bpf_cpu_map_entry *rcpu, int fd)
+static int __cpu_map_load_bpf_program(struct bpf_cpu_map_entry *rcpu,
+				      struct bpf_map *map, int fd)
 {
 	struct bpf_prog *prog;

@@ -405,7 +406,8 @@ static int __cpu_map_load_bpf_program(struct bpf_cpu_map_entry *rcpu, int fd)
 	if (IS_ERR(prog))
 		return PTR_ERR(prog);
 
-	if (prog->expected_attach_type != BPF_XDP_CPUMAP) {
+	if (prog->expected_attach_type != BPF_XDP_CPUMAP ||
+	    !bpf_prog_map_compatible(map, prog)) {
 		bpf_prog_put(prog);
 		return -EINVAL;
 	}

@@ -457,7 +459,7 @@ __cpu_map_entry_alloc(struct bpf_map *map, struct bpf_cpumap_val *value,
 	rcpu->map_id = map->id;
 	rcpu->value.qsize  = value->qsize;
 
-	if (fd > 0 && __cpu_map_load_bpf_program(rcpu, fd))
+	if (fd > 0 && __cpu_map_load_bpf_program(rcpu, map, fd))
 		goto free_ptr_ring;
 
 	/* Setup kthread */

kernel/bpf/devmap.c +2 -1

index fe019dbdb3f0..038f6d7a83e4 100644
@@ -858,7 +858,8 @@ static struct bpf_dtab_netdev *__dev_map_alloc_node(struct net *net,
 					     BPF_PROG_TYPE_XDP, false);
 		if (IS_ERR(prog))
 			goto err_put_dev;
-		if (prog->expected_attach_type != BPF_XDP_DEVMAP)
+		if (prog->expected_attach_type != BPF_XDP_DEVMAP ||
+		    !bpf_prog_map_compatible(&dtab->map, prog))
 			goto err_put_prog;
 	}

kernel/bpf/syscall.c +7 -8

index f29090643c6e..72ce1edde950 100644
@@ -556,16 +556,14 @@ static unsigned long bpf_map_memory_footprint(const struct bpf_map *map)
 
 static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp)
 {
-	const struct bpf_map *map = filp->private_data;
-	const struct bpf_array *array;
+	struct bpf_map *map = filp->private_data;
 	u32 type = 0, jited = 0;
 
-	if (map->map_type == BPF_MAP_TYPE_PROG_ARRAY) {
-		array = container_of(map, struct bpf_array, map);
-		spin_lock(&array->aux->owner.lock);
-		type  = array->aux->owner.type;
-		jited = array->aux->owner.jited;
-		spin_unlock(&array->aux->owner.lock);
+	if (map_type_contains_progs(map)) {
+		spin_lock(&map->owner.lock);
+		type  = map->owner.type;
+		jited = map->owner.jited;
+		spin_unlock(&map->owner.lock);
 	}
 
 	seq_printf(m,

@@ -874,6 +872,7 @@ static int map_create(union bpf_attr *attr)
 	atomic64_set(&map->refcnt, 1);
 	atomic64_set(&map->usercnt, 1);
 	mutex_init(&map->freeze_mutex);
+	spin_lock_init(&map->owner.lock);
 
 	map->spin_lock_off = -EINVAL;
 	map->timer_off = -EINVAL;

Signature · 1 line

2.34.1

Lorenzo Bianconi

author

2022-01-21 10:12 UTC #20 lore raw

PATCH v23 20/23 net: xdp: introduce bpf_xdp_pointer utility routine

Similar to skb_header_pointer, introduce bpf_xdp_pointer utility routine to return a pointer to a given position in the xdp_buff if the requested area (offset + len) is contained in a contiguous memory area otherwise it will be copied in a bounce buffer provided by the caller. Similar to the tc counterpart, introduce the two following xdp helpers:
- bpf_xdp_load_bytes
- bpf_xdp_store_bytes

Reviewed-by Eelco Chaudron <[email protected]>

Acked-by Toke Hoiland-Jorgensen <[email protected]>

Acked-by Jakub Kicinski <[email protected]>

---
 include/uapi/linux/bpf.h       |  18 ++++
 net/core/filter.c              | 176 ++++++++++++++++++++++++++-------
 tools/include/uapi/linux/bpf.h |  18 ++++
 3 files changed, 174 insertions(+), 38 deletions(-)

include/uapi/linux/bpf.h +18 -0

index 5a28772063f6..16a7574292a5 100644
@@ -5060,6 +5060,22 @@ union bpf_attr {
  *		Get the total size of a given xdp buff (linear and paged area)
  *	Return
  *		The total size of a given xdp buffer.
+ *
+ * long bpf_xdp_load_bytes(struct xdp_buff *xdp_md, u32 offset, void *buf, u32 len)
+ *	Description
+ *		This helper is provided as an easy way to load data from a
+ *		xdp buffer. It can be used to load *len* bytes from *offset* from
+ *		the frame associated to *xdp_md*, into the buffer pointed by
+ *		*buf*.
+ *	Return
+ *		0 on success, or a negative error in case of failure.
+ *
+ * long bpf_xdp_store_bytes(struct xdp_buff *xdp_md, u32 offset, void *buf, u32 len)
+ *	Description
+ *		Store *len* bytes from buffer *buf* into the frame
+ *		associated to *xdp_md*, at *offset*.
+ *	Return
+ *		0 on success, or a negative error in case of failure.
  */
 #define __BPF_FUNC_MAPPER(FN)		\
 	FN(unspec),			\

@@ -5251,6 +5267,8 @@ union bpf_attr {
 	FN(get_retval),			\
 	FN(set_retval),			\
 	FN(xdp_get_buff_len),		\
+	FN(xdp_load_bytes),		\
+	FN(xdp_store_bytes),		\
 	/* */
 
 /* integer value in 'imm' field of BPF_CALL instruction selects which helper

net/core/filter.c +138 ~~-38~~

198 lines not on this page · raw message

tools/include/uapi/linux/bpf.h +18 -0

index 5a28772063f6..16a7574292a5 100644
@@ -5060,6 +5060,22 @@ union bpf_attr {
  *		Get the total size of a given xdp buff (linear and paged area)
  *	Return
  *		The total size of a given xdp buffer.
+ *
+ * long bpf_xdp_load_bytes(struct xdp_buff *xdp_md, u32 offset, void *buf, u32 len)
+ *	Description
+ *		This helper is provided as an easy way to load data from a
+ *		xdp buffer. It can be used to load *len* bytes from *offset* from
+ *		the frame associated to *xdp_md*, into the buffer pointed by
+ *		*buf*.
+ *	Return
+ *		0 on success, or a negative error in case of failure.
+ *
+ * long bpf_xdp_store_bytes(struct xdp_buff *xdp_md, u32 offset, void *buf, u32 len)
+ *	Description
+ *		Store *len* bytes from buffer *buf* into the frame
+ *		associated to *xdp_md*, at *offset*.
+ *	Return
+ *		0 on success, or a negative error in case of failure.
  */
 #define __BPF_FUNC_MAPPER(FN)		\
 	FN(unspec),			\

@@ -5251,6 +5267,8 @@ union bpf_attr {
 	FN(get_retval),			\
 	FN(set_retval),			\
 	FN(xdp_get_buff_len),		\
+	FN(xdp_load_bytes),		\
+	FN(xdp_store_bytes),		\
 	/* */
 
 /* integer value in 'imm' field of BPF_CALL instruction selects which helper

Signature · 1 line

2.34.1

Lorenzo Bianconi

author

2022-01-21 10:12 UTC #21 lore raw

PATCH v23 21/23 bpf: selftests: introduce bpf_xdp_{load,store}_bytes selftest

Introduce kernel selftest for new bpf_xdp_{load,store}_bytes helpers. and bpf_xdp_pointer/bpf_xdp_copy_buf utility routines.

Acked-by Toke Hoiland-Jorgensen <[email protected]>

---
 .../bpf/prog_tests/xdp_adjust_frags.c         | 104 ++++++++++++++++++
 .../bpf/progs/test_xdp_update_frags.c         |  42 +++++++
 2 files changed, 146 insertions(+)
 create mode 100644 tools/testing/selftests/bpf/prog_tests/xdp_adjust_frags.c
 create mode 100644 tools/testing/selftests/bpf/progs/test_xdp_update_frags.c

tools/testing/selftests/bpf/prog_tests/xdp_adjust_frags.c new file +104 -0

new file mode 100644
index 000000000000..31c188666e81
@@ -0,0 +1,104 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <test_progs.h>
+#include <network_helpers.h>
+
+void test_xdp_update_frags(void)
+{
+	const char *file = "./test_xdp_update_frags.o";
+	__u32 duration, retval, size;
+	struct bpf_program *prog;
+	struct bpf_object *obj;
+	int err, prog_fd;
+	__u32 *offset;
+	__u8 *buf;
+
+	obj = bpf_object__open(file);
+	if (libbpf_get_error(obj))
+		return;
+
+	prog = bpf_object__next_program(obj, NULL);
+	if (bpf_object__load(obj))
+		return;
+
+	prog_fd = bpf_program__fd(prog);
+
+	buf = malloc(128);
+	if (!ASSERT_OK_PTR(buf, "alloc buf 128b"))
+		goto out;
+
+	memset(buf, 0, 128);
+	offset = (__u32 *)buf;
+	*offset = 16;
+	buf[*offset] = 0xaa;		/* marker at offset 16 (head) */
+	buf[*offset + 15] = 0xaa;	/* marker at offset 31 (head) */
+
+	err = bpf_prog_test_run(prog_fd, 1, buf, 128,
+				buf, &size, &retval, &duration);
+
+	/* test_xdp_update_frags: buf[16,31]: 0xaa -> 0xbb */
+	ASSERT_OK(err, "xdp_update_frag");
+	ASSERT_EQ(retval, XDP_PASS, "xdp_update_frag retval");
+	ASSERT_EQ(buf[16], 0xbb, "xdp_update_frag buf[16]");
+	ASSERT_EQ(buf[31], 0xbb, "xdp_update_frag buf[31]");
+
+	free(buf);
+
+	buf = malloc(9000);
+	if (!ASSERT_OK_PTR(buf, "alloc buf 9Kb"))
+		goto out;
+
+	memset(buf, 0, 9000);
+	offset = (__u32 *)buf;
+	*offset = 5000;
+	buf[*offset] = 0xaa;		/* marker at offset 5000 (frag0) */
+	buf[*offset + 15] = 0xaa;	/* marker at offset 5015 (frag0) */
+
+	err = bpf_prog_test_run(prog_fd, 1, buf, 9000,
+				buf, &size, &retval, &duration);
+
+	/* test_xdp_update_frags: buf[5000,5015]: 0xaa -> 0xbb */
+	ASSERT_OK(err, "xdp_update_frag");
+	ASSERT_EQ(retval, XDP_PASS, "xdp_update_frag retval");
+	ASSERT_EQ(buf[5000], 0xbb, "xdp_update_frag buf[5000]");
+	ASSERT_EQ(buf[5015], 0xbb, "xdp_update_frag buf[5015]");
+
+	memset(buf, 0, 9000);
+	offset = (__u32 *)buf;
+	*offset = 3510;
+	buf[*offset] = 0xaa;		/* marker at offset 3510 (head) */
+	buf[*offset + 15] = 0xaa;	/* marker at offset 3525 (frag0) */
+
+	err = bpf_prog_test_run(prog_fd, 1, buf, 9000,
+				buf, &size, &retval, &duration);
+
+	/* test_xdp_update_frags: buf[3510,3525]: 0xaa -> 0xbb */
+	ASSERT_OK(err, "xdp_update_frag");
+	ASSERT_EQ(retval, XDP_PASS, "xdp_update_frag retval");
+	ASSERT_EQ(buf[3510], 0xbb, "xdp_update_frag buf[3510]");
+	ASSERT_EQ(buf[3525], 0xbb, "xdp_update_frag buf[3525]");
+
+	memset(buf, 0, 9000);
+	offset = (__u32 *)buf;
+	*offset = 7606;
+	buf[*offset] = 0xaa;		/* marker at offset 7606 (frag0) */
+	buf[*offset + 15] = 0xaa;	/* marker at offset 7621 (frag1) */
+
+	err = bpf_prog_test_run(prog_fd, 1, buf, 9000,
+				buf, &size, &retval, &duration);
+
+	/* test_xdp_update_frags: buf[7606,7621]: 0xaa -> 0xbb */
+	ASSERT_OK(err, "xdp_update_frag");
+	ASSERT_EQ(retval, XDP_PASS, "xdp_update_frag retval");
+	ASSERT_EQ(buf[7606], 0xbb, "xdp_update_frag buf[7606]");
+	ASSERT_EQ(buf[7621], 0xbb, "xdp_update_frag buf[7621]");
+
+	free(buf);
+out:
+	bpf_object__close(obj);
+}
+
+void test_xdp_adjust_frags(void)
+{
+	if (test__start_subtest("xdp_adjust_frags"))
+		test_xdp_update_frags();
+}

tools/testing/selftests/bpf/progs/test_xdp_update_frags.c new file +42 -0

42 lines not on this page · raw message

Signature · 1 line

2.34.1

Lorenzo Bianconi

author

2022-01-21 10:12 UTC #22 lore raw

PATCH v23 22/23 bpf: selftests: add CPUMAP/DEVMAP selftests for xdp frags

Verify compatibility checks attaching a XDP frags program to a CPUMAP/DEVMAP

Acked-by Toke Hoiland-Jorgensen <[email protected]>

---
 .../bpf/prog_tests/xdp_cpumap_attach.c        | 64 ++++++++++++++++++-
 .../bpf/prog_tests/xdp_devmap_attach.c        | 55 ++++++++++++++++
 .../test_xdp_with_cpumap_frags_helpers.c      | 27 ++++++++
 .../bpf/progs/test_xdp_with_cpumap_helpers.c  |  6 ++
 .../test_xdp_with_devmap_frags_helpers.c      | 27 ++++++++
 .../bpf/progs/test_xdp_with_devmap_helpers.c  |  7 ++
 6 files changed, 185 insertions(+), 1 deletion(-)
 create mode 100644 tools/testing/selftests/bpf/progs/test_xdp_with_cpumap_frags_helpers.c
 create mode 100644 tools/testing/selftests/bpf/progs/test_xdp_with_devmap_frags_helpers.c

tools/testing/selftests/bpf/prog_tests/xdp_cpumap_attach.c +63 -1

index abe9d9f988ec..b353e1f3acb5 100644
@@ -3,11 +3,12 @@
 #include <linux/if_link.h>
 #include <test_progs.h>
 
+#include "test_xdp_with_cpumap_frags_helpers.skel.h"
 #include "test_xdp_with_cpumap_helpers.skel.h"
 
 #define IFINDEX_LO	1
 
-void serial_test_xdp_cpumap_attach(void)
+void test_xdp_with_cpumap_helpers(void)
 {
 	struct test_xdp_with_cpumap_helpers *skel;
 	struct bpf_prog_info info = {};

@@ -54,6 +55,67 @@ void serial_test_xdp_cpumap_attach(void)
 	err = bpf_map_update_elem(map_fd, &idx, &val, 0);
 	ASSERT_NEQ(err, 0, "Add non-BPF_XDP_CPUMAP program to cpumap entry");
 
+	/* Try to attach BPF_XDP program with frags to cpumap when we have
+	 * already loaded a BPF_XDP program on the map
+	 */
+	idx = 1;
+	val.qsize = 192;
+	val.bpf_prog.fd = bpf_program__fd(skel->progs.xdp_dummy_cm_frags);
+	err = bpf_map_update_elem(map_fd, &idx, &val, 0);
+	ASSERT_NEQ(err, 0, "Add BPF_XDP program with frags to cpumap entry");
+
 out_close:
 	test_xdp_with_cpumap_helpers__destroy(skel);
 }
+
+void test_xdp_with_cpumap_frags_helpers(void)
+{
+	struct test_xdp_with_cpumap_frags_helpers *skel;
+	struct bpf_prog_info info = {};
+	__u32 len = sizeof(info);
+	struct bpf_cpumap_val val = {
+		.qsize = 192,
+	};
+	int err, frags_prog_fd, map_fd;
+	__u32 idx = 0;
+
+	skel = test_xdp_with_cpumap_frags_helpers__open_and_load();
+	if (!ASSERT_OK_PTR(skel, "test_xdp_with_cpumap_helpers__open_and_load"))
+		return;
+
+	frags_prog_fd = bpf_program__fd(skel->progs.xdp_dummy_cm_frags);
+	map_fd = bpf_map__fd(skel->maps.cpu_map);
+	err = bpf_obj_get_info_by_fd(frags_prog_fd, &info, &len);
+	if (!ASSERT_OK(err, "bpf_obj_get_info_by_fd"))
+		goto out_close;
+
+	val.bpf_prog.fd = frags_prog_fd;
+	err = bpf_map_update_elem(map_fd, &idx, &val, 0);
+	ASSERT_OK(err, "Add program to cpumap entry");
+
+	err = bpf_map_lookup_elem(map_fd, &idx, &val);
+	ASSERT_OK(err, "Read cpumap entry");
+	ASSERT_EQ(info.id, val.bpf_prog.id,
+		  "Match program id to cpumap entry prog_id");
+
+	/* Try to attach BPF_XDP program to cpumap when we have
+	 * already loaded a BPF_XDP program with frags on the map
+	 */
+	idx = 1;
+	val.qsize = 192;
+	val.bpf_prog.fd = bpf_program__fd(skel->progs.xdp_dummy_cm);
+	err = bpf_map_update_elem(map_fd, &idx, &val, 0);
+	ASSERT_NEQ(err, 0, "Add BPF_XDP program to cpumap entry");
+
+out_close:
+	test_xdp_with_cpumap_frags_helpers__destroy(skel);
+}
+
+void serial_test_xdp_cpumap_attach(void)
+{
+	if (test__start_subtest("CPUMAP with programs in entries"))
+		test_xdp_with_cpumap_helpers();
+
+	if (test__start_subtest("CPUMAP with frags programs in entries"))
+		test_xdp_with_cpumap_frags_helpers();
+}

tools/testing/selftests/bpf/prog_tests/xdp_devmap_attach.c +55 -0

79 lines not on this page · raw message

tools/testing/selftests/bpf/progs/test_xdp_with_cpumap_frags_helpers.c new file +27 -0

new file mode 100644
index 000000000000..62fb7cd4d87a
@@ -0,0 +1,27 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/bpf.h>
+#include <bpf/bpf_helpers.h>
+
+#define IFINDEX_LO	1
+
+struct {
+	__uint(type, BPF_MAP_TYPE_CPUMAP);
+	__uint(key_size, sizeof(__u32));
+	__uint(value_size, sizeof(struct bpf_cpumap_val));
+	__uint(max_entries, 4);
+} cpu_map SEC(".maps");
+
+SEC("xdp_cpumap/dummy_cm")
+int xdp_dummy_cm(struct xdp_md *ctx)
+{
+	return XDP_PASS;
+}
+
+SEC("xdp.frags/cpumap")
+int xdp_dummy_cm_frags(struct xdp_md *ctx)
+{
+	return XDP_PASS;
+}
+
+char _license[] SEC("license") = "GPL";

tools/testing/selftests/bpf/progs/test_xdp_with_cpumap_helpers.c +6 -0

index 532025057711..48007f17dfa8 100644
@@ -33,4 +33,10 @@ int xdp_dummy_cm(struct xdp_md *ctx)
 	return XDP_PASS;
 }
 
+SEC("xdp.frags/cpumap")
+int xdp_dummy_cm_frags(struct xdp_md *ctx)
+{
+	return XDP_PASS;
+}
+
 char _license[] SEC("license") = "GPL";

tools/testing/selftests/bpf/progs/test_xdp_with_devmap_frags_helpers.c new file +27 -0

new file mode 100644
index 000000000000..e1caf510b7d2
@@ -0,0 +1,27 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/bpf.h>
+#include <bpf/bpf_helpers.h>
+
+struct {
+	__uint(type, BPF_MAP_TYPE_DEVMAP);
+	__uint(key_size, sizeof(__u32));
+	__uint(value_size, sizeof(struct bpf_devmap_val));
+	__uint(max_entries, 4);
+} dm_ports SEC(".maps");
+
+/* valid program on DEVMAP entry via SEC name;
+ * has access to egress and ingress ifindex
+ */
+SEC("xdp_devmap/map_prog")
+int xdp_dummy_dm(struct xdp_md *ctx)
+{
+	return XDP_PASS;
+}
+
+SEC("xdp.frags/devmap")
+int xdp_dummy_dm_frags(struct xdp_md *ctx)
+{
+	return XDP_PASS;
+}
+
+char _license[] SEC("license") = "GPL";

tools/testing/selftests/bpf/progs/test_xdp_with_devmap_helpers.c +7 -0

index 1e6b9c38ea6d..8ae11fab8316 100644
@@ -40,4 +40,11 @@ int xdp_dummy_dm(struct xdp_md *ctx)
 
 	return XDP_PASS;
 }
+
+SEC("xdp.frags/devmap")
+int xdp_dummy_dm_frags(struct xdp_md *ctx)
+{
+	return XDP_PASS;
+}
+
 char _license[] SEC("license") = "GPL";

Signature · 1 line

2.34.1

Lorenzo Bianconi

author

2022-01-21 10:12 UTC #23 lore raw

PATCH v23 23/23 xdp: disable XDP_REDIRECT for xdp frags

XDP_REDIRECT is not fully supported yet for xdp frags since not all XDP capable drivers can map non-linear xdp_frame in ndo_xdp_xmit so disable it for the moment.

Acked-by Toke Hoiland-Jorgensen <[email protected]>

Acked-by Jesper Dangaard Brouer <[email protected]>

---
 net/core/filter.c | 8 ++++++++
 1 file changed, 8 insertions(+)

net/core/filter.c +8 -0

index 945ccaaab3cb..a06931c27eeb 100644
@@ -4266,6 +4266,14 @@ int xdp_do_redirect(struct net_device *dev, struct xdp_buff *xdp,
 	struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
 	enum bpf_map_type map_type = ri->map_type;
 
+	/* XDP_REDIRECT is not fully supported yet for xdp frags since
+	 * not all XDP capable drivers can map non-linear xdp_frame in
+	 * ndo_xdp_xmit.
+	 */
+	if (unlikely(xdp_buff_has_frags(xdp) &&
+		     map_type != BPF_MAP_TYPE_CPUMAP))
+		return -EOPNOTSUPP;
+
 	if (map_type == BPF_MAP_TYPE_XSKMAP)
 		return __xdp_do_redirect_xsk(ri, dev, xdp, xdp_prog);

Signature · 1 line

2.34.1

Alexei Starovoitov

2022-01-21 22:21 UTC #24 lore raw