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igb: Pull timestamp from fragment before adding it to skb

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This change makes it so that we pull the timestamp from the fragment before
we add it to the skb.  By doing this we can avoid a possible issue in which
the fragment can possibly be less than IGB_RX_HDR_LEN due to the timestamp
being pulled after the copybreak check.

While making this change I realized we could also pull the rest of the
igb_pull_tail function into igb_add_rx_frag since in the case of igb,
unlike ixgbe, we are able to unmap the entire buffer before calling
add_rx_frag so merging the two allows for sharing of code between the two
merged functions.

Reported-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
This commit is contained in:
Alexander Duyck 2015-04-22 21:49:17 -07:00 committed by Jeff Kirsher
parent 11b1544b5c
commit f56e7bba22
1 changed files with 25 additions and 69 deletions
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94
drivers/net/ethernet/intel/igb/igb_main.c
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@ -6621,22 +6621,25 @@ static bool igb_add_rx_frag(struct igb_ring *rx_ring,
struct sk_buff *skb)
{
struct page *page = rx_buffer->page;
unsigned char *va = page_address(page) + rx_buffer->page_offset;
unsigned int size = le16_to_cpu(rx_desc->wb.upper.length);
#if (PAGE_SIZE < 8192)
unsigned int truesize = IGB_RX_BUFSZ;
#else
unsigned int truesize = ALIGN(size, L1_CACHE_BYTES);
unsigned int truesize = SKB_DATA_ALIGN(size);
#endif
unsigned int pull_len;
if ((size <= IGB_RX_HDR_LEN) && !skb_is_nonlinear(skb)) {
unsigned char *va = page_address(page) + rx_buffer->page_offset;
if (unlikely(skb_is_nonlinear(skb)))
goto add_tail_frag;
if (igb_test_staterr(rx_desc, E1000_RXDADV_STAT_TSIP)) {
igb_ptp_rx_pktstamp(rx_ring->q_vector, va, skb);
va += IGB_TS_HDR_LEN;
size -= IGB_TS_HDR_LEN;
}
if (unlikely(igb_test_staterr(rx_desc, E1000_RXDADV_STAT_TSIP))) {
igb_ptp_rx_pktstamp(rx_ring->q_vector, va, skb);
va += IGB_TS_HDR_LEN;
size -= IGB_TS_HDR_LEN;
}
if (likely(size <= IGB_RX_HDR_LEN)) {
memcpy(__skb_put(skb, size), va, ALIGN(size, sizeof(long)));
/* page is not reserved, we can reuse buffer as-is */
@ -6648,8 +6651,21 @@ static bool igb_add_rx_frag(struct igb_ring *rx_ring,
return false;
}
/* we need the header to contain the greater of either ETH_HLEN or
* 60 bytes if the skb->len is less than 60 for skb_pad.
*/
pull_len = eth_get_headlen(va, IGB_RX_HDR_LEN);
/* align pull length to size of long to optimize memcpy performance */
memcpy(__skb_put(skb, pull_len), va, ALIGN(pull_len, sizeof(long)));
/* update all of the pointers */
va += pull_len;
size -= pull_len;
add_tail_frag:
skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page,
rx_buffer->page_offset, size, truesize);
(unsigned long)va & ~PAGE_MASK, size, truesize);
return igb_can_reuse_rx_page(rx_buffer, page, truesize);
}
@ -6790,62 +6806,6 @@ static bool igb_is_non_eop(struct igb_ring *rx_ring,
return true;
}
/**
* igb_pull_tail - igb specific version of skb_pull_tail
* @rx_ring: rx descriptor ring packet is being transacted on
* @rx_desc: pointer to the EOP Rx descriptor
* @skb: pointer to current skb being adjusted
*
* This function is an igb specific version of __pskb_pull_tail. The
* main difference between this version and the original function is that
* this function can make several assumptions about the state of things
* that allow for significant optimizations versus the standard function.
* As a result we can do things like drop a frag and maintain an accurate
* truesize for the skb.
*/
static void igb_pull_tail(struct igb_ring *rx_ring,
union e1000_adv_rx_desc *rx_desc,
struct sk_buff *skb)
{
struct skb_frag_struct *frag = &skb_shinfo(skb)->frags[0];
unsigned char *va;
unsigned int pull_len;
/* it is valid to use page_address instead of kmap since we are
* working with pages allocated out of the lomem pool per
* alloc_page(GFP_ATOMIC)
*/
va = skb_frag_address(frag);
if (igb_test_staterr(rx_desc, E1000_RXDADV_STAT_TSIP)) {
/* retrieve timestamp from buffer */
igb_ptp_rx_pktstamp(rx_ring->q_vector, va, skb);
/* update pointers to remove timestamp header */
skb_frag_size_sub(frag, IGB_TS_HDR_LEN);
frag->page_offset += IGB_TS_HDR_LEN;
skb->data_len -= IGB_TS_HDR_LEN;
skb->len -= IGB_TS_HDR_LEN;
/* move va to start of packet data */
va += IGB_TS_HDR_LEN;
}
/* we need the header to contain the greater of either ETH_HLEN or
* 60 bytes if the skb->len is less than 60 for skb_pad.
*/
pull_len = eth_get_headlen(va, IGB_RX_HDR_LEN);
/* align pull length to size of long to optimize memcpy performance */
skb_copy_to_linear_data(skb, va, ALIGN(pull_len, sizeof(long)));
/* update all of the pointers */
skb_frag_size_sub(frag, pull_len);
frag->page_offset += pull_len;
skb->data_len -= pull_len;
skb->tail += pull_len;
}
/**
* igb_cleanup_headers - Correct corrupted or empty headers
* @rx_ring: rx descriptor ring packet is being transacted on
@ -6873,10 +6833,6 @@ static bool igb_cleanup_headers(struct igb_ring *rx_ring,
}
}
/* place header in linear portion of buffer */
if (skb_is_nonlinear(skb))
igb_pull_tail(rx_ring, rx_desc, skb);
/* if eth_skb_pad returns an error the skb was freed */
if (eth_skb_pad(skb))
return true;