2 files changed, 103 insertions, 111 deletions

diff --git a/drivers/net/ethernet/intel/idpf/idpf_txrx.c b/drivers/net/ethernet/intel/idpf/idpf_txrx.c
index 527d56bcbbef..5fe329a7c944 100644
--- a/drivers/net/ethernet/intel/idpf/idpf_txrx.c
+++ b/drivers/net/ethernet/intel/idpf/idpf_txrx.c
@@ -13,6 +13,7 @@ struct idpf_tx_stash {
 	struct libeth_sqe buf;
 };
 
+#define idpf_tx_buf_next(buf)		(*(u32 *)&(buf)->priv)
 #define idpf_tx_buf_compl_tag(buf)	(*(u32 *)&(buf)->priv)
 LIBETH_SQE_CHECK_PRIV(u32);
 
@@ -91,7 +92,7 @@ static void idpf_tx_buf_rel_all(struct idpf_tx_queue *txq)
 		return;
 
 	/* Free all the Tx buffer sk_buffs */
-	for (i = 0; i < txq->desc_count; i++)
+	for (i = 0; i < txq->buf_pool_size; i++)
 		libeth_tx_complete(&txq->tx_buf[i], &cp);
 
 	kfree(txq->tx_buf);
@@ -199,14 +200,17 @@ static void idpf_tx_desc_rel_all(struct idpf_vport *vport)
 static int idpf_tx_buf_alloc_all(struct idpf_tx_queue *tx_q)
 {
 	struct idpf_buf_lifo *buf_stack;
-	int buf_size;
 	int i;
 
 	/* Allocate book keeping buffers only. Buffers to be supplied to HW
 	 * are allocated by kernel network stack and received as part of skb
 	 */
-	buf_size = sizeof(struct idpf_tx_buf) * tx_q->desc_count;
-	tx_q->tx_buf = kzalloc(buf_size, GFP_KERNEL);
+	if (idpf_queue_has(FLOW_SCH_EN, tx_q))
+		tx_q->buf_pool_size = U16_MAX;
+	else
+		tx_q->buf_pool_size = tx_q->desc_count;
+	tx_q->tx_buf = kcalloc(tx_q->buf_pool_size, sizeof(*tx_q->tx_buf),
+			       GFP_KERNEL);
 	if (!tx_q->tx_buf)
 		return -ENOMEM;
 
@@ -275,7 +279,7 @@ static int idpf_tx_desc_alloc(const struct idpf_vport *vport,
 		return 0;
 
 	refillq = tx_q->refillq;
-	refillq->desc_count = tx_q->desc_count;
+	refillq->desc_count = tx_q->buf_pool_size;
 	refillq->ring = kcalloc(refillq->desc_count, sizeof(u32),
 				GFP_KERNEL);
 	if (!refillq->ring) {
@@ -1869,6 +1873,12 @@ static bool idpf_tx_splitq_clean(struct idpf_tx_queue *tx_q, u16 end,
 	struct idpf_tx_buf *tx_buf;
 	bool clean_complete = true;
 
+	if (descs_only) {
+		/* Bump ring index to mark as cleaned. */
+		tx_q->next_to_clean = end;
+		return true;
+	}
+
 	tx_desc = &tx_q->flex_tx[ntc];
 	next_pending_desc = &tx_q->flex_tx[end];
 	tx_buf = &tx_q->tx_buf[ntc];
@@ -1935,87 +1945,43 @@ do {							\
 } while (0)
 
 /**
- * idpf_tx_clean_buf_ring - clean flow scheduling TX queue buffers
+ * idpf_tx_clean_bufs - clean flow scheduling TX queue buffers
  * @txq: queue to clean
- * @compl_tag: completion tag of packet to clean (from completion descriptor)
+ * @buf_id: packet's starting buffer ID, from completion descriptor
  * @cleaned: pointer to stats struct to track cleaned packets/bytes
  * @budget: Used to determine if we are in netpoll
  *
- * Cleans all buffers associated with the input completion tag either from the
- * TX buffer ring or from the hash table if the buffers were previously
- * stashed. Returns the byte/segment count for the cleaned packet associated
- * this completion tag.
+ * Clean all buffers associated with the packet starting at buf_id. Returns the
+ * byte/segment count for the cleaned packet.
  */
-static bool idpf_tx_clean_buf_ring(struct idpf_tx_queue *txq, u16 compl_tag,
-				   struct libeth_sq_napi_stats *cleaned,
-				   int budget)
+static bool idpf_tx_clean_bufs(struct idpf_tx_queue *txq, u32 buf_id,
+			       struct libeth_sq_napi_stats *cleaned,
+			       int budget)
 {
-	u16 idx = compl_tag & txq->compl_tag_bufid_m;
 	struct idpf_tx_buf *tx_buf = NULL;
 	struct libeth_cq_pp cp = {
 		.dev	= txq->dev,
 		.ss	= cleaned,
 		.napi	= budget,
 	};
-	u16 ntc, orig_idx = idx;
-
-	tx_buf = &txq->tx_buf[idx];
-
-	if (unlikely(tx_buf->type <= LIBETH_SQE_CTX ||
-		     idpf_tx_buf_compl_tag(tx_buf) != compl_tag))
-		return false;
 
+	tx_buf = &txq->tx_buf[buf_id];
 	if (tx_buf->type == LIBETH_SQE_SKB) {
 		if (skb_shinfo(tx_buf->skb)->tx_flags & SKBTX_IN_PROGRESS)
 			idpf_tx_read_tstamp(txq, tx_buf->skb);
 
 		libeth_tx_complete(tx_buf, &cp);
+		idpf_post_buf_refill(txq->refillq, buf_id);
 	}
 
-	idpf_tx_clean_buf_ring_bump_ntc(txq, idx, tx_buf);
+	while (idpf_tx_buf_next(tx_buf) != IDPF_TXBUF_NULL) {
+		buf_id = idpf_tx_buf_next(tx_buf);
 
-	while (idpf_tx_buf_compl_tag(tx_buf) == compl_tag) {
+		tx_buf = &txq->tx_buf[buf_id];
 		libeth_tx_complete(tx_buf, &cp);
-		idpf_tx_clean_buf_ring_bump_ntc(txq, idx, tx_buf);
+		idpf_post_buf_refill(txq->refillq, buf_id);
 	}
 
-	/*
-	 * It's possible the packet we just cleaned was an out of order
-	 * completion, which means we can stash the buffers starting from
-	 * the original next_to_clean and reuse the descriptors. We need
-	 * to compare the descriptor ring next_to_clean packet's "first" buffer
-	 * to the "first" buffer of the packet we just cleaned to determine if
-	 * this is the case. Howevever, next_to_clean can point to either a
-	 * reserved buffer that corresponds to a context descriptor used for the
-	 * next_to_clean packet (TSO packet) or the "first" buffer (single
-	 * packet). The orig_idx from the packet we just cleaned will always
-	 * point to the "first" buffer. If next_to_clean points to a reserved
-	 * buffer, let's bump ntc once and start the comparison from there.
-	 */
-	ntc = txq->next_to_clean;
-	tx_buf = &txq->tx_buf[ntc];
-
-	if (tx_buf->type == LIBETH_SQE_CTX)
-		idpf_tx_clean_buf_ring_bump_ntc(txq, ntc, tx_buf);
-
-	/*
-	 * If ntc still points to a different "first" buffer, clean the
-	 * descriptor ring and stash all of the buffers for later cleaning. If
-	 * we cannot stash all of the buffers, next_to_clean will point to the
-	 * "first" buffer of the packet that could not be stashed and cleaning
-	 * will start there next time.
-	 */
-	if (unlikely(tx_buf != &txq->tx_buf[orig_idx] &&
-		     !idpf_tx_splitq_clean(txq, orig_idx, budget, cleaned,
-					   true)))
-		return true;
-
-	/*
-	 * Otherwise, update next_to_clean to reflect the cleaning that was
-	 * done above.
-	 */
-	txq->next_to_clean = idx;
-
 	return true;
 }
 
@@ -2046,12 +2012,10 @@ static void idpf_tx_handle_rs_completion(struct idpf_tx_queue *txq,
 
 	compl_tag = le16_to_cpu(desc->q_head_compl_tag.compl_tag);
 
-	idpf_post_buf_refill(txq->refillq, compl_tag);
-
 	/* If we didn't clean anything on the ring, this packet must be
 	 * in the hash table. Go clean it there.
 	 */
-	if (!idpf_tx_clean_buf_ring(txq, compl_tag, cleaned, budget))
+	if (!idpf_tx_clean_bufs(txq, compl_tag, cleaned, budget))
 		idpf_tx_clean_stashed_bufs(txq, compl_tag, cleaned, budget);
 }
 
@@ -2364,7 +2328,7 @@ static unsigned int idpf_tx_splitq_bump_ntu(struct idpf_tx_queue *txq, u16 ntu)
  * Return: true if a buffer ID was found, false if not
  */
 static bool idpf_tx_get_free_buf_id(struct idpf_sw_queue *refillq,
-				    u16 *buf_id)
+				    u32 *buf_id)
 {
 	u32 ntc = refillq->next_to_clean;
 	u32 refill_desc;
@@ -2397,25 +2361,34 @@ static void idpf_tx_splitq_pkt_err_unmap(struct idpf_tx_queue *txq,
 					 struct idpf_tx_splitq_params *params,
 					 struct idpf_tx_buf *first)
 {
+	struct idpf_sw_queue *refillq = txq->refillq;
 	struct libeth_sq_napi_stats ss = { };
 	struct idpf_tx_buf *tx_buf = first;
 	struct libeth_cq_pp cp = {
 		.dev    = txq->dev,
 		.ss     = &ss,
 	};
-	u32 idx = 0;
 
 	u64_stats_update_begin(&txq->stats_sync);
 	u64_stats_inc(&txq->q_stats.dma_map_errs);
 	u64_stats_update_end(&txq->stats_sync);
 
-	do {
+	libeth_tx_complete(tx_buf, &cp);
+	while (idpf_tx_buf_next(tx_buf) != IDPF_TXBUF_NULL) {
+		tx_buf = &txq->tx_buf[idpf_tx_buf_next(tx_buf)];
 		libeth_tx_complete(tx_buf, &cp);
-		idpf_tx_clean_buf_ring_bump_ntc(txq, idx, tx_buf);
-	} while (idpf_tx_buf_compl_tag(tx_buf) == params->compl_tag);
+	}
 
 	/* Update tail in case netdev_xmit_more was previously true. */
 	idpf_tx_buf_hw_update(txq, params->prev_ntu, false);
+
+	if (!refillq)
+		return;
+
+	/* Restore refillq state to avoid leaking tags. */
+	if (params->prev_refill_gen != idpf_queue_has(RFL_GEN_CHK, refillq))
+		idpf_queue_change(RFL_GEN_CHK, refillq);
+	refillq->next_to_clean = params->prev_refill_ntc;
 }
 
 /**
@@ -2439,6 +2412,7 @@ static void idpf_tx_splitq_map(struct idpf_tx_queue *tx_q,
 	struct netdev_queue *nq;
 	struct sk_buff *skb;
 	skb_frag_t *frag;
+	u32 next_buf_id;
 	u16 td_cmd = 0;
 	dma_addr_t dma;
 
@@ -2456,18 +2430,16 @@ static void idpf_tx_splitq_map(struct idpf_tx_queue *tx_q,
 	tx_buf = first;
 	first->nr_frags = 0;
 
-	params->compl_tag =
-		(tx_q->compl_tag_cur_gen << tx_q->compl_tag_gen_s) | i;
-
 	for (frag = &skb_shinfo(skb)->frags[0];; frag++) {
 		unsigned int max_data = IDPF_TX_MAX_DESC_DATA_ALIGNED;
 
-		if (unlikely(dma_mapping_error(tx_q->dev, dma)))
+		if (unlikely(dma_mapping_error(tx_q->dev, dma))) {
+			idpf_tx_buf_next(tx_buf) = IDPF_TXBUF_NULL;
 			return idpf_tx_splitq_pkt_err_unmap(tx_q, params,
 							    first);
+		}
 
 		first->nr_frags++;
-		idpf_tx_buf_compl_tag(tx_buf) = params->compl_tag;
 		tx_buf->type = LIBETH_SQE_FRAG;
 
 		/* record length, and DMA address */
@@ -2523,29 +2495,14 @@ static void idpf_tx_splitq_map(struct idpf_tx_queue *tx_q,
 						  max_data);
 
 			if (unlikely(++i == tx_q->desc_count)) {
-				tx_buf = tx_q->tx_buf;
 				tx_desc = &tx_q->flex_tx[0];
 				i = 0;
 				tx_q->compl_tag_cur_gen =
 					IDPF_TX_ADJ_COMPL_TAG_GEN(tx_q);
 			} else {
-				tx_buf++;
 				tx_desc++;
 			}
 
-			/* Since this packet has a buffer that is going to span
-			 * multiple descriptors, it's going to leave holes in
-			 * to the TX buffer ring. To ensure these holes do not
-			 * cause issues in the cleaning routines, we will clear
-			 * them of any stale data and assign them the same
-			 * completion tag as the current packet. Then when the
-			 * packet is being cleaned, the cleaning routines will
-			 * simply pass over these holes and finish cleaning the
-			 * rest of the packet.
-			 */
-			tx_buf->type = LIBETH_SQE_EMPTY;
-			idpf_tx_buf_compl_tag(tx_buf) = params->compl_tag;
-
 			/* Adjust the DMA offset and the remaining size of the
 			 * fragment.  On the first iteration of this loop,
 			 * max_data will be >= 12K and <= 16K-1.  On any
@@ -2570,15 +2527,26 @@ static void idpf_tx_splitq_map(struct idpf_tx_queue *tx_q,
 		idpf_tx_splitq_build_desc(tx_desc, params, td_cmd, size);
 
 		if (unlikely(++i == tx_q->desc_count)) {
-			tx_buf = tx_q->tx_buf;
 			tx_desc = &tx_q->flex_tx[0];
 			i = 0;
 			tx_q->compl_tag_cur_gen = IDPF_TX_ADJ_COMPL_TAG_GEN(tx_q);
 		} else {
-			tx_buf++;
 			tx_desc++;
 		}
 
+		if (idpf_queue_has(FLOW_SCH_EN, tx_q)) {
+			if (unlikely(!idpf_tx_get_free_buf_id(tx_q->refillq,
+							      &next_buf_id))) {
+				idpf_tx_buf_next(tx_buf) = IDPF_TXBUF_NULL;
+				return idpf_tx_splitq_pkt_err_unmap(tx_q, params,
+								    first);
+			}
+		} else {
+			next_buf_id = i;
+		}
+		idpf_tx_buf_next(tx_buf) = next_buf_id;
+		tx_buf = &tx_q->tx_buf[next_buf_id];
+
 		size = skb_frag_size(frag);
 		data_len -= size;
 
@@ -2593,6 +2561,7 @@ static void idpf_tx_splitq_map(struct idpf_tx_queue *tx_q,
 
 	/* write last descriptor with RS and EOP bits */
 	first->rs_idx = i;
+	idpf_tx_buf_next(tx_buf) = IDPF_TXBUF_NULL;
 	td_cmd |= params->eop_cmd;
 	idpf_tx_splitq_build_desc(tx_desc, params, td_cmd, size);
 	i = idpf_tx_splitq_bump_ntu(tx_q, i);
@@ -2801,8 +2770,6 @@ idpf_tx_splitq_get_ctx_desc(struct idpf_tx_queue *txq)
 	union idpf_flex_tx_ctx_desc *desc;
 	int i = txq->next_to_use;
 
-	txq->tx_buf[i].type = LIBETH_SQE_CTX;
-
 	/* grab the next descriptor */
 	desc = &txq->flex_ctx[i];
 	txq->next_to_use = idpf_tx_splitq_bump_ntu(txq, i);
@@ -2927,6 +2894,7 @@ static netdev_tx_t idpf_tx_splitq_frame(struct sk_buff *skb,
 	struct idpf_tx_buf *first;
 	unsigned int count;
 	int tso, idx;
+	u32 buf_id;
 
 	count = idpf_tx_desc_count_required(tx_q, skb);
 	if (unlikely(!count))
@@ -2970,26 +2938,28 @@ static netdev_tx_t idpf_tx_splitq_frame(struct sk_buff *skb,
 		idpf_tx_set_tstamp_desc(ctx_desc, idx);
 	}
 
-	/* record the location of the first descriptor for this packet */
-	first = &tx_q->tx_buf[tx_q->next_to_use];
-	first->skb = skb;
+	if (idpf_queue_has(FLOW_SCH_EN, tx_q)) {
+		struct idpf_sw_queue *refillq = tx_q->refillq;
 
-	if (tso) {
-		first->packets = tx_params.offload.tso_segs;
-		first->bytes = skb->len +
-			((first->packets - 1) * tx_params.offload.tso_hdr_len);
-	} else {
-		first->packets = 1;
-		first->bytes = max_t(unsigned int, skb->len, ETH_ZLEN);
-	}
+		/* Save refillq state in case of a packet rollback.  Otherwise,
+		 * the tags will be leaked since they will be popped from the
+		 * refillq but never reposted during cleaning.
+		 */
+		tx_params.prev_refill_gen =
+			idpf_queue_has(RFL_GEN_CHK, refillq);
+		tx_params.prev_refill_ntc = refillq->next_to_clean;
 
-	if (idpf_queue_has(FLOW_SCH_EN, tx_q)) {
 		if (unlikely(!idpf_tx_get_free_buf_id(tx_q->refillq,
-						      &tx_params.compl_tag))) {
-			u64_stats_update_begin(&tx_q->stats_sync);
-			u64_stats_inc(&tx_q->q_stats.q_busy);
-			u64_stats_update_end(&tx_q->stats_sync);
+						      &buf_id))) {
+			if (tx_params.prev_refill_gen !=
+			    idpf_queue_has(RFL_GEN_CHK, refillq))
+				idpf_queue_change(RFL_GEN_CHK, refillq);
+			refillq->next_to_clean = tx_params.prev_refill_ntc;
+
+			tx_q->next_to_use = tx_params.prev_ntu;
+			return idpf_tx_drop_skb(tx_q, skb);
 		}
+		tx_params.compl_tag = buf_id;
 
 		tx_params.dtype = IDPF_TX_DESC_DTYPE_FLEX_FLOW_SCHE;
 		tx_params.eop_cmd = IDPF_TXD_FLEX_FLOW_CMD_EOP;
@@ -3008,6 +2978,8 @@ static netdev_tx_t idpf_tx_splitq_frame(struct sk_buff *skb,
 			tx_params.offload.td_cmd |= IDPF_TXD_FLEX_FLOW_CMD_CS_EN;
 
 	} else {
+		buf_id = tx_q->next_to_use;
+
 		tx_params.dtype = IDPF_TX_DESC_DTYPE_FLEX_L2TAG1_L2TAG2;
 		tx_params.eop_cmd = IDPF_TXD_LAST_DESC_CMD;
 
@@ -3015,6 +2987,18 @@ static netdev_tx_t idpf_tx_splitq_frame(struct sk_buff *skb,
 			tx_params.offload.td_cmd |= IDPF_TX_FLEX_DESC_CMD_CS_EN;
 	}
 
+	first = &tx_q->tx_buf[buf_id];
+	first->skb = skb;
+
+	if (tso) {
+		first->packets = tx_params.offload.tso_segs;
+		first->bytes = skb->len +
+			((first->packets - 1) * tx_params.offload.tso_hdr_len);
+	} else {
+		first->packets = 1;
+		first->bytes = max_t(unsigned int, skb->len, ETH_ZLEN);
+	}
+
 	idpf_tx_splitq_map(tx_q, &tx_params, first);
 
 	return NETDEV_TX_OK;
diff --git a/drivers/net/ethernet/intel/idpf/idpf_txrx.h b/drivers/net/ethernet/intel/idpf/idpf_txrx.h
index a7632d845a2a..d86246c320c8 100644
--- a/drivers/net/ethernet/intel/idpf/idpf_txrx.h
+++ b/drivers/net/ethernet/intel/idpf/idpf_txrx.h
@@ -137,6 +137,8 @@ do {								\
 	((++(txq)->compl_tag_cur_gen) >= (txq)->compl_tag_gen_max ? \
 	0 : (txq)->compl_tag_cur_gen)
 
+#define IDPF_TXBUF_NULL			U32_MAX
+
 #define IDPF_TXD_LAST_DESC_CMD (IDPF_TX_DESC_CMD_EOP | IDPF_TX_DESC_CMD_RS)
 
 #define IDPF_TX_FLAGS_TSO		BIT(0)
@@ -197,6 +199,8 @@ struct idpf_tx_offload_params {
  * @td_tag: Descriptor tunneling tag
  * @offload: Offload parameters
  * @prev_ntu: stored TxQ next_to_use in case of rollback
+ * @prev_refill_ntc: stored refillq next_to_clean in case of packet rollback
+ * @prev_refill_gen: stored refillq generation bit in case of packet rollback
  */
 struct idpf_tx_splitq_params {
 	enum idpf_tx_desc_dtype_value dtype;
@@ -209,6 +213,8 @@ struct idpf_tx_splitq_params {
 	struct idpf_tx_offload_params offload;
 
 	u16 prev_ntu;
+	u16 prev_refill_ntc;
+	bool prev_refill_gen;
 };
 
 enum idpf_tx_ctx_desc_eipt_offload {
@@ -638,6 +644,7 @@ libeth_cacheline_set_assert(struct idpf_rx_queue, 64,
  * @size: Length of descriptor ring in bytes
  * @dma: Physical address of ring
  * @q_vector: Backreference to associated vector
+ * @buf_pool_size: Total number of idpf_tx_buf
  */
 struct idpf_tx_queue {
 	__cacheline_group_begin_aligned(read_mostly);
@@ -696,11 +703,12 @@ struct idpf_tx_queue {
 	dma_addr_t dma;
 
 	struct idpf_q_vector *q_vector;
+	u32 buf_pool_size;
 	__cacheline_group_end_aligned(cold);
 };
 libeth_cacheline_set_assert(struct idpf_tx_queue, 64,
 			    120 + sizeof(struct u64_stats_sync),
-			    24);
+			    32);
 
 /**
  * struct idpf_buf_queue - software structure representing a buffer queue