From ec61bd2fd2a27bf7368261b230ef54fe34d1cce3 Mon Sep 17 00:00:00 2001 From: Julian Wiedmann Date: Tue, 20 Jun 2017 16:00:34 +0200 Subject: [PATCH] s390/qeth: use diag26c to get MAC address on L2 When a s390 guest runs on a z/VM host that's part of a SSI cluster, it can be migrated to a different host. In this case, the MAC address it originally obtained on the old host may be re-assigned to a new guest. This would result in address conflicts between the two guests. When running as z/VM guest, use the diag26c MAC Service to obtain a hypervisor-managed MAC address. The MAC Service is SSI-aware, and won't re-assign the address after the guest is migrated to a new host. This patch adds support for the z/VM MAC Service on L2 devices. Signed-off-by: Julian Wiedmann Acked-by: Ursula Braun Signed-off-by: David S. Miller --- drivers/s390/net/qeth_core.h | 1 + drivers/s390/net/qeth_core_main.c | 61 +++++++++++++++++++++++++++++++ drivers/s390/net/qeth_l2_main.c | 16 +++++++- 3 files changed, 76 insertions(+), 2 deletions(-) diff --git a/drivers/s390/net/qeth_core.h b/drivers/s390/net/qeth_core.h index 0efc54a4d82f..7a0ffc71b25d 100644 --- a/drivers/s390/net/qeth_core.h +++ b/drivers/s390/net/qeth_core.h @@ -986,6 +986,7 @@ struct qeth_cmd_buffer *qeth_get_setassparms_cmd(struct qeth_card *, int qeth_set_features(struct net_device *, netdev_features_t); int qeth_recover_features(struct net_device *); netdev_features_t qeth_fix_features(struct net_device *, netdev_features_t); +int qeth_vm_request_mac(struct qeth_card *card); /* exports for OSN */ int qeth_osn_assist(struct net_device *, void *, int); diff --git a/drivers/s390/net/qeth_core_main.c b/drivers/s390/net/qeth_core_main.c index 13a55f1dee7a..3b657d5b7e49 100644 --- a/drivers/s390/net/qeth_core_main.c +++ b/drivers/s390/net/qeth_core_main.c @@ -27,6 +27,9 @@ #include #include #include +#include +#include +#include #include "qeth_core.h" @@ -4773,6 +4776,64 @@ static int qeth_query_card_info(struct qeth_card *card, (void *)carrier_info); } +/** + * qeth_vm_request_mac() - Request a hypervisor-managed MAC address + * @card: pointer to a qeth_card + * + * Returns + * 0, if a MAC address has been set for the card's netdevice + * a return code, for various error conditions + */ +int qeth_vm_request_mac(struct qeth_card *card) +{ + struct diag26c_mac_resp *response; + struct diag26c_mac_req *request; + struct ccw_dev_id id; + int rc; + + QETH_DBF_TEXT(SETUP, 2, "vmreqmac"); + + if (!card->dev) + return -ENODEV; + + request = kzalloc(sizeof(*request), GFP_KERNEL | GFP_DMA); + response = kzalloc(sizeof(*response), GFP_KERNEL | GFP_DMA); + if (!request || !response) { + rc = -ENOMEM; + goto out; + } + + ccw_device_get_id(CARD_DDEV(card), &id); + request->resp_buf_len = sizeof(*response); + request->resp_version = DIAG26C_VERSION2; + request->op_code = DIAG26C_GET_MAC; + request->devno = id.devno; + + rc = diag26c(request, response, DIAG26C_MAC_SERVICES); + if (rc) + goto out; + + if (request->resp_buf_len < sizeof(*response) || + response->version != request->resp_version) { + rc = -EIO; + QETH_DBF_TEXT(SETUP, 2, "badresp"); + QETH_DBF_HEX(SETUP, 2, &request->resp_buf_len, + sizeof(request->resp_buf_len)); + } else if (!is_valid_ether_addr(response->mac)) { + rc = -EINVAL; + QETH_DBF_TEXT(SETUP, 2, "badmac"); + QETH_DBF_HEX(SETUP, 2, response->mac, ETH_ALEN); + } else { + ether_addr_copy(card->dev->dev_addr, response->mac); + } + +out: + kfree(response); + kfree(request); + return rc; +} +EXPORT_SYMBOL_GPL(qeth_vm_request_mac); + static inline int qeth_get_qdio_q_format(struct qeth_card *card) { if (card->info.type == QETH_CARD_TYPE_IQD) diff --git a/drivers/s390/net/qeth_l2_main.c b/drivers/s390/net/qeth_l2_main.c index 9e7f12aba55e..ad110abfdd47 100644 --- a/drivers/s390/net/qeth_l2_main.c +++ b/drivers/s390/net/qeth_l2_main.c @@ -21,6 +21,7 @@ #include #include #include +#include #include "qeth_core.h" #include "qeth_l2.h" @@ -505,9 +506,19 @@ static int qeth_l2_request_initial_mac(struct qeth_card *card) int rc = 0; char vendor_pre[] = {0x02, 0x00, 0x00}; - QETH_DBF_TEXT(SETUP, 2, "doL2init"); + QETH_DBF_TEXT(SETUP, 2, "l2reqmac"); QETH_DBF_TEXT_(SETUP, 2, "doL2%s", CARD_BUS_ID(card)); + if (MACHINE_IS_VM) { + rc = qeth_vm_request_mac(card); + if (!rc) + goto out; + QETH_DBF_MESSAGE(2, "z/VM MAC Service failed on device %s: x%x\n", + CARD_BUS_ID(card), rc); + QETH_DBF_TEXT_(SETUP, 2, "err%04x", rc); + /* fall back to alternative mechanism: */ + } + if (qeth_is_supported(card, IPA_SETADAPTERPARMS)) { rc = qeth_query_setadapterparms(card); if (rc) { @@ -528,11 +539,12 @@ static int qeth_l2_request_initial_mac(struct qeth_card *card) QETH_DBF_TEXT_(SETUP, 2, "1err%04x", rc); return rc; } - QETH_DBF_HEX(SETUP, 2, card->dev->dev_addr, OSA_ADDR_LEN); } else { eth_random_addr(card->dev->dev_addr); memcpy(card->dev->dev_addr, vendor_pre, 3); } +out: + QETH_DBF_HEX(SETUP, 2, card->dev->dev_addr, card->dev->addr_len); return 0; } -- 2.20.1