Merge branch '40GbE' of git://git.kernel.org/pub/scm/linux/kernel/git/tnguy/next-queue

Tony Nguyen says:

====================
40GbE Intel Wired LAN Driver Updates 2021-02-12

This series contains updates to i40e, ice, and ixgbe drivers.

Maciej does cleanups on the following drivers.
For i40e, removes redundant check for XDP prog, cleans up no longer
relevant information, and removes an unused function argument.
For ice, removes local variable use, instead returning values directly.
Moves skb pointer from buffer to ring and removes an unneeded check for
xdp_prog in zero copy path. Also removes a redundant MTU check when
changing it.
For i40e, ice, and ixgbe, stores the rx_offset in the Rx ring as
the value is constant so there's no need for continual calls.

Bjorn folds a decrement into a while statement.
====================

Signed-off-by: David S. Miller <[email protected]>

Author: davem330

drivers/net/ethernet/intel/i40e/i40e_main.c

@@ -12947,9 +12947,6 @@ static int i40e_xdp_setup(struct i40e_vsi *vsi, struct bpf_prog *prog,
 		return -EINVAL;
 	}
 
-	if (!i40e_enabled_xdp_vsi(vsi) && !prog)
-		return 0;
-
 	/* When turning XDP on->off/off->on we reset and rebuild the rings. */
 	need_reset = (i40e_enabled_xdp_vsi(vsi) != !!prog);
 

drivers/net/ethernet/intel/i40e/i40e_txrx.c

@@ -1569,6 +1569,17 @@ void i40e_free_rx_resources(struct i40e_ring *rx_ring)
 	}
 }
 
+/**
+ * i40e_rx_offset - Return expected offset into page to access data
+ * @rx_ring: Ring we are requesting offset of
+ *
+ * Returns the offset value for ring into the data buffer.
+ */
+static unsigned int i40e_rx_offset(struct i40e_ring *rx_ring)
+{
+	return ring_uses_build_skb(rx_ring) ? I40E_SKB_PAD : 0;
+}
+
 /**
  * i40e_setup_rx_descriptors - Allocate Rx descriptors
  * @rx_ring: Rx descriptor ring (for a specific queue) to setup
@@ -1597,6 +1608,7 @@ int i40e_setup_rx_descriptors(struct i40e_ring *rx_ring)
 	rx_ring->next_to_alloc = 0;
 	rx_ring->next_to_clean = 0;
 	rx_ring->next_to_use = 0;
+	rx_ring->rx_offset = i40e_rx_offset(rx_ring);
 
 	/* XDP RX-queue info only needed for RX rings exposed to XDP */
 	if (rx_ring->vsi->type == I40E_VSI_MAIN) {
@@ -1632,17 +1644,6 @@ void i40e_release_rx_desc(struct i40e_ring *rx_ring, u32 val)
 	writel(val, rx_ring->tail);
 }
 
-/**
- * i40e_rx_offset - Return expected offset into page to access data
- * @rx_ring: Ring we are requesting offset of
- *
- * Returns the offset value for ring into the data buffer.
- */
-static inline unsigned int i40e_rx_offset(struct i40e_ring *rx_ring)
-{
-	return ring_uses_build_skb(rx_ring) ? I40E_SKB_PAD : 0;
-}
-
 static unsigned int i40e_rx_frame_truesize(struct i40e_ring *rx_ring,
 					   unsigned int size)
 {
@@ -1651,8 +1652,8 @@ static unsigned int i40e_rx_frame_truesize(struct i40e_ring *rx_ring,
 #if (PAGE_SIZE < 8192)
 	truesize = i40e_rx_pg_size(rx_ring) / 2; /* Must be power-of-2 */
 #else
-	truesize = i40e_rx_offset(rx_ring) ?
-		SKB_DATA_ALIGN(size + i40e_rx_offset(rx_ring)) +
+	truesize = rx_ring->rx_offset ?
+		SKB_DATA_ALIGN(size + rx_ring->rx_offset) +
 		SKB_DATA_ALIGN(sizeof(struct skb_shared_info)) :
 		SKB_DATA_ALIGN(size);
 #endif
@@ -1703,7 +1704,7 @@ static bool i40e_alloc_mapped_page(struct i40e_ring *rx_ring,
 
 	bi->dma = dma;
 	bi->page = page;
-	bi->page_offset = i40e_rx_offset(rx_ring);
+	bi->page_offset = rx_ring->rx_offset;
 	page_ref_add(page, USHRT_MAX - 1);
 	bi->pagecnt_bias = USHRT_MAX;
 
@@ -1963,9 +1964,6 @@ void i40e_process_skb_fields(struct i40e_ring *rx_ring,
  * @skb: pointer to current skb being fixed
  * @rx_desc: pointer to the EOP Rx descriptor
  *
- * Also address the case where we are pulling data in on pages only
- * and as such no data is present in the skb header.
- *
  * In addition if skb is not at least 60 bytes we need to pad it so that
  * it is large enough to qualify as a valid Ethernet frame.
  *
@@ -1998,33 +1996,15 @@ static bool i40e_cleanup_headers(struct i40e_ring *rx_ring, struct sk_buff *skb,
 }
 
 /**
- * i40e_can_reuse_rx_page - Determine if this page can be reused by
- * the adapter for another receive
- *
+ * i40e_can_reuse_rx_page - Determine if page can be reused for another Rx
  * @rx_buffer: buffer containing the page
  * @rx_buffer_pgcnt: buffer page refcount pre xdp_do_redirect() call
  *
- * If page is reusable, rx_buffer->page_offset is adjusted to point to
- * an unused region in the page.
- *
- * For small pages, @truesize will be a constant value, half the size
- * of the memory at page.  We'll attempt to alternate between high and
- * low halves of the page, with one half ready for use by the hardware
- * and the other half being consumed by the stack.  We use the page
- * ref count to determine whether the stack has finished consuming the
- * portion of this page that was passed up with a previous packet.  If
- * the page ref count is >1, we'll assume the "other" half page is
- * still busy, and this page cannot be reused.
- *
- * For larger pages, @truesize will be the actual space used by the
- * received packet (adjusted upward to an even multiple of the cache
- * line size).  This will advance through the page by the amount
- * actually consumed by the received packets while there is still
- * space for a buffer.  Each region of larger pages will be used at
- * most once, after which the page will not be reused.
- *
- * In either case, if the page is reusable its refcount is increased.
- **/
+ * If page is reusable, we have a green light for calling i40e_reuse_rx_page,
+ * which will assign the current buffer to the buffer that next_to_alloc is
+ * pointing to; otherwise, the DMA mapping needs to be destroyed and
+ * page freed
+ */
 static bool i40e_can_reuse_rx_page(struct i40e_rx_buffer *rx_buffer,
 				   int rx_buffer_pgcnt)
 {
@@ -2078,7 +2058,7 @@ static void i40e_add_rx_frag(struct i40e_ring *rx_ring,
 #if (PAGE_SIZE < 8192)
 	unsigned int truesize = i40e_rx_pg_size(rx_ring) / 2;
 #else
-	unsigned int truesize = SKB_DATA_ALIGN(size + i40e_rx_offset(rx_ring));
+	unsigned int truesize = SKB_DATA_ALIGN(size + rx_ring->rx_offset);
 #endif
 
 	skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, rx_buffer->page,
@@ -2292,25 +2272,13 @@ static void i40e_put_rx_buffer(struct i40e_ring *rx_ring,
  * i40e_is_non_eop - process handling of non-EOP buffers
  * @rx_ring: Rx ring being processed
  * @rx_desc: Rx descriptor for current buffer
- * @skb: Current socket buffer containing buffer in progress
  *
- * This function updates next to clean.  If the buffer is an EOP buffer
- * this function exits returning false, otherwise it will place the
- * sk_buff in the next buffer to be chained and return true indicating
- * that this is in fact a non-EOP buffer.
- **/
+ * If the buffer is an EOP buffer, this function exits returning false,
+ * otherwise return true indicating that this is in fact a non-EOP buffer.
+ */
 static bool i40e_is_non_eop(struct i40e_ring *rx_ring,
-			    union i40e_rx_desc *rx_desc,
-			    struct sk_buff *skb)
+			    union i40e_rx_desc *rx_desc)
 {
-	u32 ntc = rx_ring->next_to_clean + 1;
-
-	/* fetch, update, and store next to clean */
-	ntc = (ntc < rx_ring->count) ? ntc : 0;
-	rx_ring->next_to_clean = ntc;
-
-	prefetch(I40E_RX_DESC(rx_ring, ntc));
-
 	/* if we are the last buffer then there is nothing else to do */
 #define I40E_RXD_EOF BIT(I40E_RX_DESC_STATUS_EOF_SHIFT)
 	if (likely(i40e_test_staterr(rx_desc, I40E_RXD_EOF)))
@@ -2486,8 +2454,9 @@ static void i40e_inc_ntc(struct i40e_ring *rx_ring)
 static int i40e_clean_rx_irq(struct i40e_ring *rx_ring, int budget)
 {
 	unsigned int total_rx_bytes = 0, total_rx_packets = 0, frame_sz = 0;
-	struct sk_buff *skb = rx_ring->skb;
 	u16 cleaned_count = I40E_DESC_UNUSED(rx_ring);
+	unsigned int offset = rx_ring->rx_offset;
+	struct sk_buff *skb = rx_ring->skb;
 	unsigned int xdp_xmit = 0;
 	bool failure = false;
 	struct xdp_buff xdp;
@@ -2547,7 +2516,6 @@ static int i40e_clean_rx_irq(struct i40e_ring *rx_ring, int budget)
 
 		/* retrieve a buffer from the ring */
 		if (!skb) {
-			unsigned int offset = i40e_rx_offset(rx_ring);
 			unsigned char *hard_start;
 
 			hard_start = page_address(rx_buffer->page) +
@@ -2589,7 +2557,8 @@ static int i40e_clean_rx_irq(struct i40e_ring *rx_ring, int budget)
 		i40e_put_rx_buffer(rx_ring, rx_buffer, rx_buffer_pgcnt);
 		cleaned_count++;
 
-		if (i40e_is_non_eop(rx_ring, rx_desc, skb))
+		i40e_inc_ntc(rx_ring);
+		if (i40e_is_non_eop(rx_ring, rx_desc))
 			continue;
 
 		if (i40e_cleanup_headers(rx_ring, skb, rx_desc)) {

drivers/net/ethernet/intel/i40e/i40e_txrx.h

@@ -387,6 +387,7 @@ struct i40e_ring {
 					 */
 
 	struct i40e_channel *ch;
+	u16 rx_offset;
 	struct xdp_rxq_info xdp_rxq;
 	struct xsk_buff_pool *xsk_pool;
 	struct xdp_desc *xsk_descs;      /* For storing descriptors in the AF_XDP ZC path */

drivers/net/ethernet/intel/i40e/i40e_xsk.c

@@ -215,9 +215,7 @@ bool i40e_alloc_rx_buffers_zc(struct i40e_ring *rx_ring, u16 count)
 			bi = i40e_rx_bi(rx_ring, 0);
 			ntu = 0;
 		}
-
-		count--;
-	} while (count);
+	} while (--count);
 
 no_buffers:
 	if (rx_ring->next_to_use != ntu) {

drivers/net/ethernet/intel/ice/ice_main.c

@@ -6154,15 +6154,6 @@ static int ice_change_mtu(struct net_device *netdev, int new_mtu)
 		}
 	}
 
-	if (new_mtu < (int)netdev->min_mtu) {
-		netdev_err(netdev, "new MTU invalid. min_mtu is %d\n",
-			   netdev->min_mtu);
-		return -EINVAL;
-	} else if (new_mtu > (int)netdev->max_mtu) {
-		netdev_err(netdev, "new MTU invalid. max_mtu is %d\n",
-			   netdev->min_mtu);
-		return -EINVAL;
-	}
 	/* if a reset is in progress, wait for some time for it to complete */
 	do {
 		if (ice_is_reset_in_progress(pf->state)) {