From 8ce7a9e064db4a31e9d9d08300e2f3e9679eaffe Mon Sep 17 00:00:00 2001 From: Julian Wiedmann Date: Thu, 19 Jul 2018 12:43:53 +0200 Subject: [PATCH] s390/qeth: simplify max MTU handling When the MPC initialization code discovers the HW-specific max MTU, apply the resulting changes straight to the netdevice. If this is the device's first initialization, also set its MTU (HiperSockets: the max MTU; else: a layer-specific default value). Then cap the current MTU by the new max MTU. Signed-off-by: Julian Wiedmann Signed-off-by: David S. Miller --- drivers/s390/net/qeth_core.h | 2 - drivers/s390/net/qeth_core_main.c | 82 +++++++++++++++++-------------- drivers/s390/net/qeth_l2_main.c | 1 - drivers/s390/net/qeth_l3_main.c | 1 - 4 files changed, 45 insertions(+), 41 deletions(-) diff --git a/drivers/s390/net/qeth_core.h b/drivers/s390/net/qeth_core.h index 04b900c7060d..6f02a6cbe59e 100644 --- a/drivers/s390/net/qeth_core.h +++ b/drivers/s390/net/qeth_core.h @@ -660,8 +660,6 @@ struct qeth_card_info { int mac_bits; enum qeth_card_types type; enum qeth_link_types link_type; - int initial_mtu; - int max_mtu; int broadcast_capable; int unique_id; bool layer_enforced; diff --git a/drivers/s390/net/qeth_core_main.c b/drivers/s390/net/qeth_core_main.c index 39c429787c4d..ab3d63f98779 100644 --- a/drivers/s390/net/qeth_core_main.c +++ b/drivers/s390/net/qeth_core_main.c @@ -2278,19 +2278,42 @@ static int qeth_cm_setup(struct qeth_card *card) } -static int qeth_get_initial_mtu_for_card(struct qeth_card *card) +static int qeth_update_max_mtu(struct qeth_card *card, unsigned int max_mtu) { - switch (card->info.type) { - case QETH_CARD_TYPE_IQD: - return card->info.max_mtu; - case QETH_CARD_TYPE_OSD: - case QETH_CARD_TYPE_OSX: - if (!card->options.layer2) - return ETH_DATA_LEN - 8; /* L3: allow for LLC + SNAP */ - /* fall through */ - default: - return ETH_DATA_LEN; + struct net_device *dev = card->dev; + unsigned int new_mtu; + + if (!max_mtu) { + /* IQD needs accurate max MTU to set up its RX buffers: */ + if (IS_IQD(card)) + return -EINVAL; + /* tolerate quirky HW: */ + max_mtu = ETH_MAX_MTU; + } + + rtnl_lock(); + if (IS_IQD(card)) { + /* move any device with default MTU to new max MTU: */ + new_mtu = (dev->mtu == dev->max_mtu) ? max_mtu : dev->mtu; + + /* adjust RX buffer size to new max MTU: */ + card->qdio.in_buf_size = max_mtu + 2 * PAGE_SIZE; + if (dev->max_mtu && dev->max_mtu != max_mtu) + qeth_free_qdio_buffers(card); + } else { + if (dev->mtu) + new_mtu = dev->mtu; + /* default MTUs for first setup: */ + else if (card->options.layer2) + new_mtu = ETH_DATA_LEN; + else + new_mtu = ETH_DATA_LEN - 8; /* allow for LLC + SNAP */ } + + dev->max_mtu = max_mtu; + dev->mtu = min(new_mtu, max_mtu); + rtnl_unlock(); + return 0; } static int qeth_get_mtu_outof_framesize(int framesize) @@ -2316,8 +2339,7 @@ static int qeth_mtu_is_valid(struct qeth_card *card, int mtu) case QETH_CARD_TYPE_OSM: case QETH_CARD_TYPE_OSX: case QETH_CARD_TYPE_IQD: - return ((mtu >= 576) && - (mtu <= card->info.max_mtu)); + return ((mtu >= 576) && (mtu <= card->dev->max_mtu)); case QETH_CARD_TYPE_OSN: default: return 1; @@ -2342,28 +2364,10 @@ static int qeth_ulp_enable_cb(struct qeth_card *card, struct qeth_reply *reply, if (card->info.type == QETH_CARD_TYPE_IQD) { memcpy(&framesize, QETH_ULP_ENABLE_RESP_MAX_MTU(iob->data), 2); mtu = qeth_get_mtu_outof_framesize(framesize); - if (!mtu) { - iob->rc = -EINVAL; - QETH_DBF_TEXT_(SETUP, 2, " rc%d", iob->rc); - return 0; - } - if (card->info.initial_mtu && (card->info.initial_mtu != mtu)) { - /* frame size has changed */ - if ((card->dev->mtu == card->info.initial_mtu) || - (card->dev->mtu > mtu)) - card->dev->mtu = mtu; - qeth_free_qdio_buffers(card); - } - card->info.initial_mtu = mtu; - card->info.max_mtu = mtu; - card->qdio.in_buf_size = mtu + 2 * PAGE_SIZE; } else { - card->info.max_mtu = *(__u16 *)QETH_ULP_ENABLE_RESP_MAX_MTU( - iob->data); - card->info.initial_mtu = min(card->info.max_mtu, - qeth_get_initial_mtu_for_card(card)); - card->qdio.in_buf_size = QETH_IN_BUF_SIZE_DEFAULT; + mtu = *(__u16 *)QETH_ULP_ENABLE_RESP_MAX_MTU(iob->data); } + *(u16 *)reply->param = mtu; memcpy(&len, QETH_ULP_ENABLE_RESP_DIFINFO_LEN(iob->data), 2); if (len >= QETH_MPC_DIFINFO_LEN_INDICATES_LINK_TYPE) { @@ -2382,6 +2386,7 @@ static int qeth_ulp_enable(struct qeth_card *card) int rc; char prot_type; struct qeth_cmd_buffer *iob; + u16 max_mtu; /*FIXME: trace view callbacks*/ QETH_DBF_TEXT(SETUP, 2, "ulpenabl"); @@ -2404,9 +2409,10 @@ static int qeth_ulp_enable(struct qeth_card *card) memcpy(QETH_ULP_ENABLE_FILTER_TOKEN(iob->data), &card->token.ulp_filter_w, QETH_MPC_TOKEN_LENGTH); rc = qeth_send_control_data(card, ULP_ENABLE_SIZE, iob, - qeth_ulp_enable_cb, NULL); - return rc; - + qeth_ulp_enable_cb, &max_mtu); + if (rc) + return rc; + return qeth_update_max_mtu(card, max_mtu); } static int qeth_ulp_setup_cb(struct qeth_card *card, struct qeth_reply *reply, @@ -5691,7 +5697,9 @@ static struct net_device *qeth_alloc_netdev(struct qeth_card *card) dev->ml_priv = card; dev->watchdog_timeo = QETH_TX_TIMEOUT; dev->min_mtu = 64; - dev->max_mtu = ETH_MAX_MTU; + /* initialized when device first goes online: */ + dev->max_mtu = 0; + dev->mtu = 0; SET_NETDEV_DEV(dev, &card->gdev->dev); netif_carrier_off(dev); return dev; diff --git a/drivers/s390/net/qeth_l2_main.c b/drivers/s390/net/qeth_l2_main.c index 8392fc7e809c..00d8bb1d2a41 100644 --- a/drivers/s390/net/qeth_l2_main.c +++ b/drivers/s390/net/qeth_l2_main.c @@ -944,7 +944,6 @@ static int qeth_l2_setup_netdev(struct qeth_card *card) return 0; card->dev->priv_flags |= IFF_UNICAST_FLT; - card->dev->mtu = card->info.initial_mtu; card->dev->netdev_ops = &qeth_l2_netdev_ops; if (card->info.type == QETH_CARD_TYPE_OSN) { card->dev->ethtool_ops = &qeth_l2_osn_ops; diff --git a/drivers/s390/net/qeth_l3_main.c b/drivers/s390/net/qeth_l3_main.c index 72c8f323801b..e5fa8e5ac1b3 100644 --- a/drivers/s390/net/qeth_l3_main.c +++ b/drivers/s390/net/qeth_l3_main.c @@ -2579,7 +2579,6 @@ static int qeth_l3_setup_netdev(struct qeth_card *card) } else return -ENODEV; - card->dev->mtu = card->info.initial_mtu; card->dev->ethtool_ops = &qeth_l3_ethtool_ops; card->dev->priv_flags &= ~IFF_TX_SKB_SHARING; card->dev->needed_headroom = sizeof(struct qeth_hdr) - ETH_HLEN; -- GitLab