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authorJulian Wiedmann <jwi@linux.ibm.com>2020-05-06 10:09:46 +0200
committerDavid S. Miller <davem@davemloft.net>2020-05-06 14:11:26 -0700
commita875fd1620ffb65f4e0d488f7fe1fba62cf9fedd (patch)
tree7200ae122329d79fe140d0321765613955379583 /drivers/s390
parentfff1aceb880f509fa02341acf0adca905513f139 (diff)
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s390/qeth: indicate contiguous TX buffer elements
The TX path usually maps the full content of a page into a buffer element. But there's specific skb layouts (ie. linearized TSO skbs) where the HW header (1) requires a separate buffer element, and (2) is page-contiguous with the packet data that's mapped into the next buffer element. Flag such buffer elements accordingly, so that HW can optimize its data access for them. Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/s390')
-rw-r--r--drivers/s390/net/qeth_core_main.c12
1 files changed, 10 insertions, 2 deletions
diff --git a/drivers/s390/net/qeth_core_main.c b/drivers/s390/net/qeth_core_main.c
index 9c9a6edb5384..4d1d053eebb7 100644
--- a/drivers/s390/net/qeth_core_main.c
+++ b/drivers/s390/net/qeth_core_main.c
@@ -4110,8 +4110,16 @@ static unsigned int qeth_fill_buffer(struct qeth_qdio_out_buffer *buf,
buffer->element[element].addr = virt_to_phys(hdr);
buffer->element[element].length = hd_len;
buffer->element[element].eflags = SBAL_EFLAGS_FIRST_FRAG;
- /* remember to free cache-allocated HW header: */
- buf->is_header[element] = ((void *)hdr != skb->data);
+
+ /* HW header is allocated from cache: */
+ if ((void *)hdr != skb->data)
+ buf->is_header[element] = 1;
+ /* HW header was pushed and is contiguous with linear part: */
+ else if (length > 0 && !PAGE_ALIGNED(data) &&
+ (data == (char *)hdr + hd_len))
+ buffer->element[element].eflags |=
+ SBAL_EFLAGS_CONTIGUOUS;
+
element++;
}