/* * net/dsa/tag_trailer.c - Trailer tag format handling * Copyright (c) 2008-2009 Marvell Semiconductor * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. */ #include #include #include #include "dsa_priv.h" static struct sk_buff *trailer_xmit(struct sk_buff *skb, struct net_device *dev) { struct dsa_slave_priv *p = netdev_priv(dev); struct sk_buff *nskb; int padlen; u8 *trailer; /* * We have to make sure that the trailer ends up as the very * last 4 bytes of the packet. This means that we have to pad * the packet to the minimum ethernet frame size, if necessary, * before adding the trailer. */ padlen = 0; if (skb->len < 60) padlen = 60 - skb->len; nskb = alloc_skb(NET_IP_ALIGN + skb->len + padlen + 4, GFP_ATOMIC); if (nskb == NULL) { kfree_skb(skb); return NULL; } skb_reserve(nskb, NET_IP_ALIGN); skb_reset_mac_header(nskb); skb_set_network_header(nskb, skb_network_header(skb) - skb->head); skb_set_transport_header(nskb, skb_transport_header(skb) - skb->head); skb_copy_and_csum_dev(skb, skb_put(nskb, skb->len)); kfree_skb(skb); if (padlen) { u8 *pad = skb_put(nskb, padlen); memset(pad, 0, padlen); } trailer = skb_put(nskb, 4); trailer[0] = 0x80; trailer[1] = 1 << p->port; trailer[2] = 0x10; trailer[3] = 0x00; return nskb; } static int trailer_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev) { struct dsa_switch_tree *dst = dev->dsa_ptr; struct dsa_switch *ds; u8 *trailer; int source_port; if (unlikely(dst == NULL)) goto out_drop; ds = dst->ds[0]; skb = skb_unshare(skb, GFP_ATOMIC); if (skb == NULL) goto out; if (skb_linearize(skb)) goto out_drop; trailer = skb_tail_pointer(skb) - 4; if (trailer[0] != 0x80 || (trailer[1] & 0xf8) != 0x00 || (trailer[2] & 0xef) != 0x00 || trailer[3] != 0x00) goto out_drop; source_port = trailer[1] & 7; if (source_port >= DSA_MAX_PORTS || !ds->ports[source_port].netdev) goto out_drop; pskb_trim_rcsum(skb, skb->len - 4); skb->dev = ds->ports[source_port].netdev; skb_push(skb, ETH_HLEN); skb->pkt_type = PACKET_HOST; skb->protocol = eth_type_trans(skb, skb->dev); skb->dev->stats.rx_packets++; skb->dev->stats.rx_bytes += skb->len; netif_receive_skb(skb); return 0; out_drop: kfree_skb(skb); out: return 0; } const struct dsa_device_ops trailer_netdev_ops = { .xmit = trailer_xmit, .rcv = trailer_rcv, }; tter
path: root/net/nfc/llcp_commands.c
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authorChristoph Hellwig <hch@lst.de>2017-02-05 18:10:35 +0100
committerJens Axboe <axboe@fb.com>2017-02-06 09:34:46 -0700
commiteeeefd41843218c55a8782a6920f044d9bf6207a (patch)
treec342eac46626e62745aa8e1a982626efca8b121d /net/nfc/llcp_commands.c
parentc14024dbb156c8392908aaa822097d27c6af8ec8 (diff)
block: don't try Write Same from __blkdev_issue_zeroout
Write Same can return an error asynchronously if it turns out the underlying SCSI device does not support Write Same, which makes a proper fallback to other methods in __blkdev_issue_zeroout impossible. Thus only issue a Write Same from blkdev_issue_zeroout an don't try it at all from __blkdev_issue_zeroout as a non-invasive workaround. Signed-off-by: Christoph Hellwig <hch@lst.de> Reported-by: Junichi Nomura <j-nomura@ce.jp.nec.com> Fixes: e73c23ff ("block: add async variant of blkdev_issue_zeroout") Tested-by: Junichi Nomura <j-nomura@ce.jp.nec.com> Signed-off-by: Jens Axboe <axboe@fb.com>
Diffstat (limited to 'net/nfc/llcp_commands.c')