Commit 439ce140 authored by Anton Blanchard's avatar Anton Blanchard Committed by Alexander Graf
Browse files

spapr-vlan: Don't touch last entry in buffer list 



The last 8 bytes of the buffer list is defined to contain the number
of dropped frames. At the moment we use it to store rx entries,
which trips up ethtool -S:

rx_no_buffer: 9223380832981355136

Fix this by skipping the last buffer list entry.

Signed-off-by: default avatarAnton Blanchard <anton@samba.org>
Reviewed-by: default avatarDavid Gibson <david@gibson.dropbear.id.au>
Signed-off-by: default avatarAlexander Graf <agraf@suse.de>
parent 32420522

hw/net/spapr_llan.c

+10 −3
Original line number Diff line number Diff line
@@ -72,7 +72,14 @@ typedef uint64_t vlan_bd_t; 
#define VLAN_RXQ_BD_OFF      0

#define VLAN_FILTER_BD_OFF   8

#define VLAN_RX_BDS_OFF      16

#define VLAN_MAX_BUFS        ((SPAPR_TCE_PAGE_SIZE - VLAN_RX_BDS_OFF) / 8)

/*

 * The final 8 bytes of the buffer list is a counter of frames dropped

 * because there was not a buffer in the buffer list capable of holding

 * the frame. We must avoid it, or the operating system will report garbage

 * for this statistic.

 */

#define VLAN_RX_BDS_LEN      (SPAPR_TCE_PAGE_SIZE - VLAN_RX_BDS_OFF - 8)

#define VLAN_MAX_BUFS        (VLAN_RX_BDS_LEN / 8)



#define TYPE_VIO_SPAPR_VLAN_DEVICE "spapr-vlan"

#define VIO_SPAPR_VLAN_DEVICE(obj) \
@@ -119,7 +126,7 @@ static ssize_t spapr_vlan_receive(NetClientState *nc, const uint8_t *buf, 


    do {

        buf_ptr += 8;

        if (buf_ptr >= SPAPR_TCE_PAGE_SIZE) {

        if (buf_ptr >= (VLAN_RX_BDS_LEN + VLAN_RX_BDS_OFF)) {

            buf_ptr = VLAN_RX_BDS_OFF;

        }
@@ -397,7 +404,7 @@ static target_ulong h_add_logical_lan_buffer(PowerPCCPU *cpu, 


    do {

        dev->add_buf_ptr += 8;

        if (dev->add_buf_ptr >= SPAPR_TCE_PAGE_SIZE) {

        if (dev->add_buf_ptr >= (VLAN_RX_BDS_LEN + VLAN_RX_BDS_OFF)) {

            dev->add_buf_ptr = VLAN_RX_BDS_OFF;

        }