net: dsa: tag_8021q: fix the VLAN IDs used for encoding sub-VLANs

[ Upstream commit 4ef8d857b5f494e62bce9085031563fda35f9563 ]

When using sub-VLANs in the range of 1-7, the resulting value from:

	rx_vid = dsa_8021q_rx_vid_subvlan(ds, port, subvlan);

is wrong according to the description from tag_8021q.c:

 | 11  | 10  |  9  |  8  |  7  |  6  |  5  |  4  |  3  |  2  |  1  |  0  |
 +-----------+-----+-----------------+-----------+-----------------------+
 |    DIR    | SVL |    SWITCH_ID    |  SUBVLAN  |          PORT         |
 +-----------+-----+-----------------+-----------+-----------------------+

For example, when ds->index == 0, port == 3 and subvlan == 1,
dsa_8021q_rx_vid_subvlan() returns 1027, same as it returns for
subvlan == 0, but it should have returned 1043.

This is because the low portion of the subvlan bits are not masked
properly when writing into the 12-bit VLAN value. They are masked into
bits 4:3, but they should be masked into bits 5:4.

Fixes: 3eaae1d05f ("net: dsa: tag_8021q: support up to 8 VLANs per port using sub-VLANs")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Vladimir Oltean 2021-05-31 13:20:45 +03:00 committed by Greg Kroah-Hartman
parent 091283e3d5
commit 09fdb6747b

View File

@ -64,7 +64,7 @@
#define DSA_8021Q_SUBVLAN_HI_SHIFT 9
#define DSA_8021Q_SUBVLAN_HI_MASK GENMASK(9, 9)
#define DSA_8021Q_SUBVLAN_LO_SHIFT 4
#define DSA_8021Q_SUBVLAN_LO_MASK GENMASK(4, 3)
#define DSA_8021Q_SUBVLAN_LO_MASK GENMASK(5, 4)
#define DSA_8021Q_SUBVLAN_HI(x) (((x) & GENMASK(2, 2)) >> 2)
#define DSA_8021Q_SUBVLAN_LO(x) ((x) & GENMASK(1, 0))
#define DSA_8021Q_SUBVLAN(x) \