From c04b116a2866b3e3a6b909a576769ccde3d622ac Mon Sep 17 00:00:00 2001 From: Julian Wiedmann Date: Mon, 23 Dec 2019 15:22:25 +0100 Subject: [PATCH 1/3] s390/qeth: consolidate RX code To reduce the path length and levels of indirection, move the RX processing from the sub-drivers into the core. Signed-off-by: Julian Wiedmann Signed-off-by: David S. Miller --- drivers/s390/net/qeth_core.h | 16 --- drivers/s390/net/qeth_core_main.c | 182 +++++++++++++++++++++++++----- drivers/s390/net/qeth_l2_main.c | 40 ------- drivers/s390/net/qeth_l3_main.c | 91 --------------- 4 files changed, 154 insertions(+), 175 deletions(-) diff --git a/drivers/s390/net/qeth_core.h b/drivers/s390/net/qeth_core.h index 6e16b19732f6..4ab3be814ea7 100644 --- a/drivers/s390/net/qeth_core.h +++ b/drivers/s390/net/qeth_core.h @@ -728,7 +728,6 @@ struct qeth_osn_info { struct qeth_discipline { const struct device_type *devtype; - int (*process_rx_buffer)(struct qeth_card *card, int budget, int *done); int (*recover)(void *ptr); int (*setup) (struct ccwgroup_device *); void (*remove) (struct ccwgroup_device *); @@ -923,18 +922,6 @@ static inline struct dst_entry *qeth_dst_check_rcu(struct sk_buff *skb, int ipv) return dst; } -static inline void qeth_rx_csum(struct qeth_card *card, struct sk_buff *skb, - u8 flags) -{ - if ((card->dev->features & NETIF_F_RXCSUM) && - (flags & QETH_HDR_EXT_CSUM_TRANSP_REQ)) { - skb->ip_summed = CHECKSUM_UNNECESSARY; - QETH_CARD_STAT_INC(card, rx_skb_csum); - } else { - skb->ip_summed = CHECKSUM_NONE; - } -} - static inline void qeth_tx_csum(struct sk_buff *skb, u8 *flags, int ipv) { *flags |= QETH_HDR_EXT_CSUM_TRANSP_REQ; @@ -1031,9 +1018,6 @@ struct qeth_cmd_buffer *qeth_get_diag_cmd(struct qeth_card *card, void qeth_notify_cmd(struct qeth_cmd_buffer *iob, int reason); void qeth_put_cmd(struct qeth_cmd_buffer *iob); -struct sk_buff *qeth_core_get_next_skb(struct qeth_card *, - struct qeth_qdio_buffer *, struct qdio_buffer_element **, int *, - struct qeth_hdr **); void qeth_schedule_recovery(struct qeth_card *); int qeth_poll(struct napi_struct *napi, int budget); void qeth_clear_ipacmd_list(struct qeth_card *); diff --git a/drivers/s390/net/qeth_core_main.c b/drivers/s390/net/qeth_core_main.c index 41f37ce89a4f..8e2c0588525f 100644 --- a/drivers/s390/net/qeth_core_main.c +++ b/drivers/s390/net/qeth_core_main.c @@ -5046,6 +5046,114 @@ out: } EXPORT_SYMBOL_GPL(qeth_core_hardsetup_card); +#if IS_ENABLED(CONFIG_QETH_L3) +static void qeth_l3_rebuild_skb(struct qeth_card *card, struct sk_buff *skb, + struct qeth_hdr *hdr) +{ + struct af_iucv_trans_hdr *iucv = (struct af_iucv_trans_hdr *) skb->data; + struct qeth_hdr_layer3 *l3_hdr = &hdr->hdr.l3; + struct net_device *dev = skb->dev; + + if (IS_IQD(card) && iucv->magic == ETH_P_AF_IUCV) { + dev_hard_header(skb, dev, ETH_P_AF_IUCV, dev->dev_addr, + "FAKELL", skb->len); + return; + } + + if (!(l3_hdr->flags & QETH_HDR_PASSTHRU)) { + u16 prot = (l3_hdr->flags & QETH_HDR_IPV6) ? ETH_P_IPV6 : + ETH_P_IP; + unsigned char tg_addr[ETH_ALEN]; + + skb_reset_network_header(skb); + switch (l3_hdr->flags & QETH_HDR_CAST_MASK) { + case QETH_CAST_MULTICAST: + if (prot == ETH_P_IP) + ip_eth_mc_map(ip_hdr(skb)->daddr, tg_addr); + else + ipv6_eth_mc_map(&ipv6_hdr(skb)->daddr, tg_addr); + QETH_CARD_STAT_INC(card, rx_multicast); + break; + case QETH_CAST_BROADCAST: + ether_addr_copy(tg_addr, dev->broadcast); + QETH_CARD_STAT_INC(card, rx_multicast); + break; + default: + if (card->options.sniffer) + skb->pkt_type = PACKET_OTHERHOST; + ether_addr_copy(tg_addr, dev->dev_addr); + } + + if (l3_hdr->ext_flags & QETH_HDR_EXT_SRC_MAC_ADDR) + dev_hard_header(skb, dev, prot, tg_addr, + &l3_hdr->next_hop.rx.src_mac, skb->len); + else + dev_hard_header(skb, dev, prot, tg_addr, "FAKELL", + skb->len); + } + + /* copy VLAN tag from hdr into skb */ + if (!card->options.sniffer && + (l3_hdr->ext_flags & (QETH_HDR_EXT_VLAN_FRAME | + QETH_HDR_EXT_INCLUDE_VLAN_TAG))) { + u16 tag = (l3_hdr->ext_flags & QETH_HDR_EXT_VLAN_FRAME) ? + l3_hdr->vlan_id : + l3_hdr->next_hop.rx.vlan_id; + + __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), tag); + } +} +#endif + +static void qeth_receive_skb(struct qeth_card *card, struct sk_buff *skb, + struct qeth_hdr *hdr) +{ + bool is_cso; + + switch (hdr->hdr.l2.id) { + case QETH_HEADER_TYPE_OSN: + skb_push(skb, sizeof(*hdr)); + skb_copy_to_linear_data(skb, hdr, sizeof(*hdr)); + QETH_CARD_STAT_ADD(card, rx_bytes, skb->len); + QETH_CARD_STAT_INC(card, rx_packets); + + card->osn_info.data_cb(skb); + return; +#if IS_ENABLED(CONFIG_QETH_L3) + case QETH_HEADER_TYPE_LAYER3: + qeth_l3_rebuild_skb(card, skb, hdr); + is_cso = hdr->hdr.l3.ext_flags & QETH_HDR_EXT_CSUM_TRANSP_REQ; + break; +#endif + case QETH_HEADER_TYPE_LAYER2: + is_cso = hdr->hdr.l2.flags[1] & QETH_HDR_EXT_CSUM_TRANSP_REQ; + break; + default: + /* never happens */ + dev_kfree_skb_any(skb); + return; + } + + if (is_cso && (card->dev->features & NETIF_F_RXCSUM)) { + skb->ip_summed = CHECKSUM_UNNECESSARY; + QETH_CARD_STAT_INC(card, rx_skb_csum); + } else { + skb->ip_summed = CHECKSUM_NONE; + } + + skb->protocol = eth_type_trans(skb, skb->dev); + + QETH_CARD_STAT_ADD(card, rx_bytes, skb->len); + QETH_CARD_STAT_INC(card, rx_packets); + if (skb_is_nonlinear(skb)) { + QETH_CARD_STAT_INC(card, rx_sg_skbs); + QETH_CARD_STAT_ADD(card, rx_sg_frags, + skb_shinfo(skb)->nr_frags); + } + + napi_gro_receive(&card->napi, skb); +} + static void qeth_create_skb_frag(struct sk_buff *skb, char *data, int data_len) { struct page *page = virt_to_page(data); @@ -5062,10 +5170,10 @@ static inline int qeth_is_last_sbale(struct qdio_buffer_element *sbale) return (sbale->eflags & SBAL_EFLAGS_LAST_ENTRY); } -struct sk_buff *qeth_core_get_next_skb(struct qeth_card *card, - struct qeth_qdio_buffer *qethbuffer, - struct qdio_buffer_element **__element, int *__offset, - struct qeth_hdr **hdr) +static int qeth_extract_skb(struct qeth_card *card, + struct qeth_qdio_buffer *qethbuffer, + struct qdio_buffer_element **__element, + int *__offset) { struct qdio_buffer_element *element = *__element; struct qdio_buffer *buffer = qethbuffer->buffer; @@ -5073,6 +5181,7 @@ struct sk_buff *qeth_core_get_next_skb(struct qeth_card *card, int offset = *__offset; bool use_rx_sg = false; unsigned int headroom; + struct qeth_hdr *hdr; struct sk_buff *skb; int skb_len = 0; @@ -5080,42 +5189,42 @@ next_packet: /* qeth_hdr must not cross element boundaries */ while (element->length < offset + sizeof(struct qeth_hdr)) { if (qeth_is_last_sbale(element)) - return NULL; + return -ENODATA; element++; offset = 0; } - *hdr = element->addr + offset; - offset += sizeof(struct qeth_hdr); + hdr = element->addr + offset; + offset += sizeof(*hdr); skb = NULL; - switch ((*hdr)->hdr.l2.id) { + switch (hdr->hdr.l2.id) { case QETH_HEADER_TYPE_LAYER2: - skb_len = (*hdr)->hdr.l2.pkt_length; + skb_len = hdr->hdr.l2.pkt_length; linear_len = ETH_HLEN; headroom = 0; break; case QETH_HEADER_TYPE_LAYER3: - skb_len = (*hdr)->hdr.l3.length; + skb_len = hdr->hdr.l3.length; if (!IS_LAYER3(card)) { QETH_CARD_STAT_INC(card, rx_dropped_notsupp); goto walk_packet; } - if ((*hdr)->hdr.l3.flags & QETH_HDR_PASSTHRU) { + if (hdr->hdr.l3.flags & QETH_HDR_PASSTHRU) { linear_len = ETH_HLEN; headroom = 0; break; } - if ((*hdr)->hdr.l3.flags & QETH_HDR_IPV6) + if (hdr->hdr.l3.flags & QETH_HDR_IPV6) linear_len = sizeof(struct ipv6hdr); else linear_len = sizeof(struct iphdr); headroom = ETH_HLEN; break; case QETH_HEADER_TYPE_OSN: - skb_len = (*hdr)->hdr.osn.pdu_length; + skb_len = hdr->hdr.osn.pdu_length; if (!IS_OSN(card)) { QETH_CARD_STAT_INC(card, rx_dropped_notsupp); goto walk_packet; @@ -5125,13 +5234,13 @@ next_packet: headroom = sizeof(struct qeth_hdr); break; default: - if ((*hdr)->hdr.l2.id & QETH_HEADER_MASK_INVAL) + if (hdr->hdr.l2.id & QETH_HEADER_MASK_INVAL) QETH_CARD_STAT_INC(card, rx_frame_errors); else QETH_CARD_STAT_INC(card, rx_dropped_notsupp); /* Can't determine packet length, drop the whole buffer. */ - return NULL; + return -EPROTONOSUPPORT; } if (skb_len < linear_len) { @@ -5195,7 +5304,7 @@ walk_packet: QETH_CARD_STAT_INC(card, rx_length_errors); } - return NULL; + return -EMSGSIZE; } element++; offset = 0; @@ -5208,22 +5317,40 @@ walk_packet: *__element = element; *__offset = offset; - if (use_rx_sg) { - QETH_CARD_STAT_INC(card, rx_sg_skbs); - QETH_CARD_STAT_ADD(card, rx_sg_frags, - skb_shinfo(skb)->nr_frags); - } - return skb; + + qeth_receive_skb(card, skb, hdr); + return 0; +} + +static int qeth_extract_skbs(struct qeth_card *card, int budget, + struct qeth_qdio_buffer *buf, bool *done) +{ + int work_done = 0; + + WARN_ON_ONCE(!budget); + *done = false; + + while (budget) { + if (qeth_extract_skb(card, buf, &card->rx.b_element, + &card->rx.e_offset)) { + *done = true; + break; + } + + work_done++; + budget--; + } + + return work_done; } -EXPORT_SYMBOL_GPL(qeth_core_get_next_skb); int qeth_poll(struct napi_struct *napi, int budget) { struct qeth_card *card = container_of(napi, struct qeth_card, napi); int work_done = 0; struct qeth_qdio_buffer *buffer; - int done; int new_budget = budget; + bool done; while (1) { if (!card->rx.b_count) { @@ -5246,11 +5373,10 @@ int qeth_poll(struct napi_struct *napi, int budget) if (!(card->rx.qdio_err && qeth_check_qdio_errors(card, buffer->buffer, card->rx.qdio_err, "qinerr"))) - work_done += - card->discipline->process_rx_buffer( - card, new_budget, &done); + work_done += qeth_extract_skbs(card, new_budget, + buffer, &done); else - done = 1; + done = true; if (done) { QETH_CARD_STAT_INC(card, rx_bufs); diff --git a/drivers/s390/net/qeth_l2_main.c b/drivers/s390/net/qeth_l2_main.c index 8c95e6019bac..69d147c4d2ca 100644 --- a/drivers/s390/net/qeth_l2_main.c +++ b/drivers/s390/net/qeth_l2_main.c @@ -298,45 +298,6 @@ static void qeth_l2_stop_card(struct qeth_card *card) card->info.promisc_mode = 0; } -static int qeth_l2_process_inbound_buffer(struct qeth_card *card, - int budget, int *done) -{ - int work_done = 0; - struct sk_buff *skb; - struct qeth_hdr *hdr; - unsigned int len; - - *done = 0; - WARN_ON_ONCE(!budget); - while (budget) { - skb = qeth_core_get_next_skb(card, - &card->qdio.in_q->bufs[card->rx.b_index], - &card->rx.b_element, &card->rx.e_offset, &hdr); - if (!skb) { - *done = 1; - break; - } - - if (hdr->hdr.l2.id == QETH_HEADER_TYPE_LAYER2) { - skb->protocol = eth_type_trans(skb, skb->dev); - qeth_rx_csum(card, skb, hdr->hdr.l2.flags[1]); - len = skb->len; - napi_gro_receive(&card->napi, skb); - } else { - skb_push(skb, sizeof(*hdr)); - skb_copy_to_linear_data(skb, hdr, sizeof(*hdr)); - len = skb->len; - card->osn_info.data_cb(skb); - } - - work_done++; - budget--; - QETH_CARD_STAT_INC(card, rx_packets); - QETH_CARD_STAT_ADD(card, rx_bytes, len); - } - return work_done; -} - static int qeth_l2_request_initial_mac(struct qeth_card *card) { int rc = 0; @@ -961,7 +922,6 @@ static int qeth_l2_control_event(struct qeth_card *card, struct qeth_discipline qeth_l2_discipline = { .devtype = &qeth_l2_devtype, - .process_rx_buffer = qeth_l2_process_inbound_buffer, .recover = qeth_l2_recover, .setup = qeth_l2_probe_device, .remove = qeth_l2_remove_device, diff --git a/drivers/s390/net/qeth_l3_main.c b/drivers/s390/net/qeth_l3_main.c index 04d7777b7d16..8a1535ee1467 100644 --- a/drivers/s390/net/qeth_l3_main.c +++ b/drivers/s390/net/qeth_l3_main.c @@ -1164,96 +1164,6 @@ static int qeth_l3_vlan_rx_kill_vid(struct net_device *dev, return 0; } -static void qeth_l3_rebuild_skb(struct qeth_card *card, struct sk_buff *skb, - struct qeth_hdr *hdr) -{ - struct af_iucv_trans_hdr *iucv = (struct af_iucv_trans_hdr *) skb->data; - struct net_device *dev = skb->dev; - - if (IS_IQD(card) && iucv->magic == ETH_P_AF_IUCV) { - dev_hard_header(skb, dev, ETH_P_AF_IUCV, dev->dev_addr, - "FAKELL", skb->len); - return; - } - - if (!(hdr->hdr.l3.flags & QETH_HDR_PASSTHRU)) { - u16 prot = (hdr->hdr.l3.flags & QETH_HDR_IPV6) ? ETH_P_IPV6 : - ETH_P_IP; - unsigned char tg_addr[ETH_ALEN]; - - skb_reset_network_header(skb); - switch (hdr->hdr.l3.flags & QETH_HDR_CAST_MASK) { - case QETH_CAST_MULTICAST: - if (prot == ETH_P_IP) - ip_eth_mc_map(ip_hdr(skb)->daddr, tg_addr); - else - ipv6_eth_mc_map(&ipv6_hdr(skb)->daddr, tg_addr); - QETH_CARD_STAT_INC(card, rx_multicast); - break; - case QETH_CAST_BROADCAST: - ether_addr_copy(tg_addr, card->dev->broadcast); - QETH_CARD_STAT_INC(card, rx_multicast); - break; - default: - if (card->options.sniffer) - skb->pkt_type = PACKET_OTHERHOST; - ether_addr_copy(tg_addr, card->dev->dev_addr); - } - - if (hdr->hdr.l3.ext_flags & QETH_HDR_EXT_SRC_MAC_ADDR) - card->dev->header_ops->create(skb, card->dev, prot, - tg_addr, &hdr->hdr.l3.next_hop.rx.src_mac, - skb->len); - else - card->dev->header_ops->create(skb, card->dev, prot, - tg_addr, "FAKELL", skb->len); - } - - /* copy VLAN tag from hdr into skb */ - if (!card->options.sniffer && - (hdr->hdr.l3.ext_flags & (QETH_HDR_EXT_VLAN_FRAME | - QETH_HDR_EXT_INCLUDE_VLAN_TAG))) { - u16 tag = (hdr->hdr.l3.ext_flags & QETH_HDR_EXT_VLAN_FRAME) ? - hdr->hdr.l3.vlan_id : - hdr->hdr.l3.next_hop.rx.vlan_id; - __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), tag); - } - - qeth_rx_csum(card, skb, hdr->hdr.l3.ext_flags); -} - -static int qeth_l3_process_inbound_buffer(struct qeth_card *card, - int budget, int *done) -{ - int work_done = 0; - struct sk_buff *skb; - struct qeth_hdr *hdr; - - *done = 0; - WARN_ON_ONCE(!budget); - while (budget) { - skb = qeth_core_get_next_skb(card, - &card->qdio.in_q->bufs[card->rx.b_index], - &card->rx.b_element, &card->rx.e_offset, &hdr); - if (!skb) { - *done = 1; - break; - } - - if (hdr->hdr.l3.id == QETH_HEADER_TYPE_LAYER3) - qeth_l3_rebuild_skb(card, skb, hdr); - - skb->protocol = eth_type_trans(skb, skb->dev); - QETH_CARD_STAT_INC(card, rx_packets); - QETH_CARD_STAT_ADD(card, rx_bytes, skb->len); - - napi_gro_receive(&card->napi, skb); - work_done++; - budget--; - } - return work_done; -} - static void qeth_l3_stop_card(struct qeth_card *card) { QETH_CARD_TEXT(card, 2, "stopcard"); @@ -2317,7 +2227,6 @@ static int qeth_l3_control_event(struct qeth_card *card, struct qeth_discipline qeth_l3_discipline = { .devtype = &qeth_l3_devtype, - .process_rx_buffer = qeth_l3_process_inbound_buffer, .recover = qeth_l3_recover, .setup = qeth_l3_probe_device, .remove = qeth_l3_remove_device, From dcdcf8670dad7547cff59ef9ddd7312fc706464a Mon Sep 17 00:00:00 2001 From: Julian Wiedmann Date: Mon, 23 Dec 2019 15:22:26 +0100 Subject: [PATCH 2/3] s390/qeth: use napi_gro_frags() for SG skbs For non-linear packets, get the skb for attaching the page fragments from napi_get_frags() so that it can be recycled during GRO. Signed-off-by: Julian Wiedmann Signed-off-by: David S. Miller --- drivers/s390/net/qeth_core_main.c | 67 +++++++++++++++++++++++-------- 1 file changed, 50 insertions(+), 17 deletions(-) diff --git a/drivers/s390/net/qeth_core_main.c b/drivers/s390/net/qeth_core_main.c index 8e2c0588525f..b32b50384c5c 100644 --- a/drivers/s390/net/qeth_core_main.c +++ b/drivers/s390/net/qeth_core_main.c @@ -5106,8 +5106,9 @@ static void qeth_l3_rebuild_skb(struct qeth_card *card, struct sk_buff *skb, #endif static void qeth_receive_skb(struct qeth_card *card, struct sk_buff *skb, - struct qeth_hdr *hdr) + struct qeth_hdr *hdr, bool uses_frags) { + struct napi_struct *napi = &card->napi; bool is_cso; switch (hdr->hdr.l2.id) { @@ -5130,7 +5131,10 @@ static void qeth_receive_skb(struct qeth_card *card, struct sk_buff *skb, break; default: /* never happens */ - dev_kfree_skb_any(skb); + if (uses_frags) + napi_free_frags(napi); + else + dev_kfree_skb_any(skb); return; } @@ -5141,8 +5145,6 @@ static void qeth_receive_skb(struct qeth_card *card, struct sk_buff *skb, skb->ip_summed = CHECKSUM_NONE; } - skb->protocol = eth_type_trans(skb, skb->dev); - QETH_CARD_STAT_ADD(card, rx_bytes, skb->len); QETH_CARD_STAT_INC(card, rx_packets); if (skb_is_nonlinear(skb)) { @@ -5151,7 +5153,12 @@ static void qeth_receive_skb(struct qeth_card *card, struct sk_buff *skb, skb_shinfo(skb)->nr_frags); } - napi_gro_receive(&card->napi, skb); + if (uses_frags) { + napi_gro_frags(napi); + } else { + skb->protocol = eth_type_trans(skb, skb->dev); + napi_gro_receive(napi, skb); + } } static void qeth_create_skb_frag(struct sk_buff *skb, char *data, int data_len) @@ -5177,7 +5184,9 @@ static int qeth_extract_skb(struct qeth_card *card, { struct qdio_buffer_element *element = *__element; struct qdio_buffer *buffer = qethbuffer->buffer; + struct napi_struct *napi = &card->napi; unsigned int linear_len = 0; + bool uses_frags = false; int offset = *__offset; bool use_rx_sg = false; unsigned int headroom; @@ -5253,21 +5262,42 @@ next_packet: !atomic_read(&card->force_alloc_skb) && !IS_OSN(card)); - if (use_rx_sg && qethbuffer->rx_skb) { + if (use_rx_sg) { /* QETH_CQ_ENABLED only: */ - skb = qethbuffer->rx_skb; - qethbuffer->rx_skb = NULL; - } else { - if (!use_rx_sg) - linear_len = skb_len; - skb = napi_alloc_skb(&card->napi, linear_len + headroom); + if (qethbuffer->rx_skb) { + skb = qethbuffer->rx_skb; + qethbuffer->rx_skb = NULL; + goto use_skb; + } + + skb = napi_get_frags(napi); + if (!skb) { + /* -ENOMEM, no point in falling back further. */ + QETH_CARD_STAT_INC(card, rx_dropped_nomem); + goto walk_packet; + } + + if (skb_tailroom(skb) >= linear_len + headroom) { + uses_frags = true; + goto use_skb; + } + + netdev_info_once(card->dev, + "Insufficient linear space in NAPI frags skb, need %u but have %u\n", + linear_len + headroom, skb_tailroom(skb)); + /* Shouldn't happen. Don't optimize, fall back to linear skb. */ } - if (!skb) + linear_len = skb_len; + skb = napi_alloc_skb(napi, linear_len + headroom); + if (!skb) { QETH_CARD_STAT_INC(card, rx_dropped_nomem); - else if (headroom) - skb_reserve(skb, headroom); + goto walk_packet; + } +use_skb: + if (headroom) + skb_reserve(skb, headroom); walk_packet: while (skb_len) { int data_len = min(skb_len, (int)(element->length - offset)); @@ -5300,7 +5330,10 @@ walk_packet: QETH_CARD_TEXT(card, 4, "unexeob"); QETH_CARD_HEX(card, 2, buffer, sizeof(void *)); if (skb) { - dev_kfree_skb_any(skb); + if (uses_frags) + napi_free_frags(napi); + else + dev_kfree_skb_any(skb); QETH_CARD_STAT_INC(card, rx_length_errors); } @@ -5318,7 +5351,7 @@ walk_packet: *__element = element; *__offset = offset; - qeth_receive_skb(card, skb, hdr); + qeth_receive_skb(card, skb, hdr, uses_frags); return 0; } From 8ca8559ff3cefd78e12b9658f21cc8bcc02407ec Mon Sep 17 00:00:00 2001 From: Julian Wiedmann Date: Mon, 23 Dec 2019 15:22:27 +0100 Subject: [PATCH 3/3] s390/qeth: remove QETH_RX_PULL_LEN Since commit f677fcb9aeb6 ("s390/qeth: ensure linear access to packet headers"), the CQ-specific skbs are allocated with a slightly bigger linear part than necessary. Shrink it down to the maximum that's needed by qeth_extract_skb(). Signed-off-by: Julian Wiedmann Signed-off-by: David S. Miller --- drivers/s390/net/qeth_core.h | 1 - drivers/s390/net/qeth_core_main.c | 6 ++++-- 2 files changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/s390/net/qeth_core.h b/drivers/s390/net/qeth_core.h index 4ab3be814ea7..7c37e94fb28b 100644 --- a/drivers/s390/net/qeth_core.h +++ b/drivers/s390/net/qeth_core.h @@ -221,7 +221,6 @@ struct qeth_vnicc_info { /* large receive scatter gather copy break */ #define QETH_RX_SG_CB (PAGE_SIZE >> 1) -#define QETH_RX_PULL_LEN 256 struct qeth_hdr_layer3 { __u8 id; diff --git a/drivers/s390/net/qeth_core_main.c b/drivers/s390/net/qeth_core_main.c index b32b50384c5c..3be3d13f8d65 100644 --- a/drivers/s390/net/qeth_core_main.c +++ b/drivers/s390/net/qeth_core_main.c @@ -2627,7 +2627,8 @@ static int qeth_init_input_buffer(struct qeth_card *card, if ((card->options.cq == QETH_CQ_ENABLED) && (!buf->rx_skb)) { buf->rx_skb = netdev_alloc_skb(card->dev, - QETH_RX_PULL_LEN + ETH_HLEN); + ETH_HLEN + + sizeof(struct ipv6hdr)); if (!buf->rx_skb) return 1; } @@ -5264,7 +5265,8 @@ next_packet: if (use_rx_sg) { /* QETH_CQ_ENABLED only: */ - if (qethbuffer->rx_skb) { + if (qethbuffer->rx_skb && + skb_tailroom(qethbuffer->rx_skb) >= linear_len + headroom) { skb = qethbuffer->rx_skb; qethbuffer->rx_skb = NULL; goto use_skb;