fix #1622: i40e memory leak

cherry-pick from upstream 4.14

patches/kernel/0017-i40e-Fix-memory-leak-related-filter-programming-stat.patch

@@ -0,0 +1,127 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Alexander Duyck <[email protected]>
+Date: Wed, 4 Oct 2017 08:44:43 -0700
+Subject: [PATCH] i40e: Fix memory leak related filter programming status
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+It looks like we weren't correctly placing the pages from buffers that had
+been used to return a filter programming status back on the ring. As a
+result they were being overwritten and tracking of the pages was lost.
+
+This change works to correct that by incorporating part of
+i40e_put_rx_buffer into the programming status handler code. As a result we
+should now be correctly placing the pages for those buffers on the
+re-allocation list instead of letting them stay in place.
+
+Fixes: 0e626ff7ccbf ("i40e: Fix support for flow director programming status")
+Reported-by: Anders K. Pedersen <[email protected]>
+Signed-off-by: Alexander Duyck <[email protected]>
+Tested-by: Anders K Pedersen <[email protected]>
+Signed-off-by: Jeff Kirsher <[email protected]>
+(cherry picked from commit 2b9478ffc550f17c6cd8c69057234e91150f5972)
+Signed-off-by: Fabian Grünbichler <[email protected]>
+---
+ drivers/net/ethernet/intel/i40e/i40e_txrx.c | 63 ++++++++++++++++-------------
+ 1 file changed, 36 insertions(+), 27 deletions(-)
+
+diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.c b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
+index 2194960d5855..391b1878c24b 100644
+--- a/drivers/net/ethernet/intel/i40e/i40e_txrx.c
++++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
+@@ -1042,6 +1042,32 @@ static bool i40e_set_new_dynamic_itr(struct i40e_ring_container *rc)
+ 	return false;
+ }
+ 
++/**
++ * i40e_reuse_rx_page - page flip buffer and store it back on the ring
++ * @rx_ring: rx descriptor ring to store buffers on
++ * @old_buff: donor buffer to have page reused
++ *
++ * Synchronizes page for reuse by the adapter
++ **/
++static void i40e_reuse_rx_page(struct i40e_ring *rx_ring,
++			       struct i40e_rx_buffer *old_buff)
++{
++	struct i40e_rx_buffer *new_buff;
++	u16 nta = rx_ring->next_to_alloc;
++
++	new_buff = &rx_ring->rx_bi[nta];
++
++	/* update, and store next to alloc */
++	nta++;
++	rx_ring->next_to_alloc = (nta < rx_ring->count) ? nta : 0;
++
++	/* transfer page from old buffer to new buffer */
++	new_buff->dma		= old_buff->dma;
++	new_buff->page		= old_buff->page;
++	new_buff->page_offset	= old_buff->page_offset;
++	new_buff->pagecnt_bias	= old_buff->pagecnt_bias;
++}
++
+ /**
+  * i40e_rx_is_programming_status - check for programming status descriptor
+  * @qw: qword representing status_error_len in CPU ordering
+@@ -1076,15 +1102,24 @@ static void i40e_clean_programming_status(struct i40e_ring *rx_ring,
+ 					  union i40e_rx_desc *rx_desc,
+ 					  u64 qw)
+ {
+-	u32 ntc = rx_ring->next_to_clean + 1;
++	struct i40e_rx_buffer *rx_buffer;
++	u32 ntc = rx_ring->next_to_clean;
+ 	u8 id;
+ 
+ 	/* fetch, update, and store next to clean */
++	rx_buffer = &rx_ring->rx_bi[ntc++];
+ 	ntc = (ntc < rx_ring->count) ? ntc : 0;
+ 	rx_ring->next_to_clean = ntc;
+ 
+ 	prefetch(I40E_RX_DESC(rx_ring, ntc));
+ 
++	/* place unused page back on the ring */
++	i40e_reuse_rx_page(rx_ring, rx_buffer);
++	rx_ring->rx_stats.page_reuse_count++;
++
++	/* clear contents of buffer_info */
++	rx_buffer->page = NULL;
++
+ 	id = (qw & I40E_RX_PROG_STATUS_DESC_QW1_PROGID_MASK) >>
+ 		  I40E_RX_PROG_STATUS_DESC_QW1_PROGID_SHIFT;
+ 
+@@ -1643,32 +1678,6 @@ static bool i40e_cleanup_headers(struct i40e_ring *rx_ring, struct sk_buff *skb,
+ 	return false;
+ }
+ 
+-/**
+- * i40e_reuse_rx_page - page flip buffer and store it back on the ring
+- * @rx_ring: rx descriptor ring to store buffers on
+- * @old_buff: donor buffer to have page reused
+- *
+- * Synchronizes page for reuse by the adapter
+- **/
+-static void i40e_reuse_rx_page(struct i40e_ring *rx_ring,
+-			       struct i40e_rx_buffer *old_buff)
+-{
+-	struct i40e_rx_buffer *new_buff;
+-	u16 nta = rx_ring->next_to_alloc;
+-
+-	new_buff = &rx_ring->rx_bi[nta];
+-
+-	/* update, and store next to alloc */
+-	nta++;
+-	rx_ring->next_to_alloc = (nta < rx_ring->count) ? nta : 0;
+-
+-	/* transfer page from old buffer to new buffer */
+-	new_buff->dma		= old_buff->dma;
+-	new_buff->page		= old_buff->page;
+-	new_buff->page_offset	= old_buff->page_offset;
+-	new_buff->pagecnt_bias	= old_buff->pagecnt_bias;
+-}
+-
+ /**
+  * i40e_page_is_reusable - check if any reuse is possible
+  * @page: page struct to check
+-- 
+2.14.2
+