- 19 11月, 2011 2 次提交
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由 Herbert Xu 提交于
packet: Add needed_tailroom to packet_sendmsg_spkt While auditing LL_ALLOCATED_SPACE I noticed that packet_sendmsg_spkt did not include needed_tailroom when allocating an skb. This isn't a fatal error as we should always tolerate inadequate tail room but it isn't optimal. This patch fixes that. Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Herbert Xu 提交于
net: Remove all uses of LL_ALLOCATED_SPACE The macro LL_ALLOCATED_SPACE was ill-conceived. It applies the alignment to the sum of needed_headroom and needed_tailroom. As the amount that is then reserved for head room is needed_headroom with alignment, this means that the tail room left may be too small. This patch replaces all uses of LL_ALLOCATED_SPACE with the macro LL_RESERVED_SPACE and direct reference to needed_tailroom. This also fixes the problem with needed_headroom changing between allocating the skb and reserving the head room. Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 04 11月, 2011 1 次提交
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由 Olof Johansson 提交于
This popped some compiler errors due to mismatched prototypes. Just remove most manual inlines, the compiler should be able to figure out what makes sense to inline and not. net/packet/af_packet.c:252: warning: 'prb_curr_blk_in_use' declared inline after being called net/packet/af_packet.c:252: warning: previous declaration of 'prb_curr_blk_in_use' was here net/packet/af_packet.c:258: warning: 'prb_queue_frozen' declared inline after being called net/packet/af_packet.c:258: warning: previous declaration of 'prb_queue_frozen' was here net/packet/af_packet.c:248: warning: 'packet_previous_frame' declared inline after being called net/packet/af_packet.c:248: warning: previous declaration of 'packet_previous_frame' was here net/packet/af_packet.c:251: warning: 'packet_increment_head' declared inline after being called net/packet/af_packet.c:251: warning: previous declaration of 'packet_increment_head' was here Signed-off-by: NOlof Johansson <olof@lixom.net> Cc: Chetan Loke <loke.chetan@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 19 10月, 2011 1 次提交
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由 Eric Dumazet 提交于
Fragmented multicast frames are delivered to a single macvlan port, because ip defrag logic considers other samples are redundant. Implement a defrag step before trying to send the multicast frame. Reported-by: NBen Greear <greearb@candelatech.com> Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 11 10月, 2011 1 次提交
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If skb is NULL, then stack trace is thrown anyway on dereference. Therefore, the stack trace triggered by BUG_ON is duplicate. Signed-off-by: NDaniel Borkmann <danborkmann@googlemail.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: NEric Dumazet <eric.dumazet@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 04 10月, 2011 1 次提交
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由 Willem de Bruijn 提交于
This is a minor change. Up until kernel 2.6.32, getsockopt(fd, SOL_PACKET, PACKET_STATISTICS, ...) would return total and dropped packets since its last invocation. The introduction of socket queue overflow reporting [1] changed drop rate calculation in the normal packet socket path, but not when using a packet ring. As a result, the getsockopt now returns different statistics depending on the reception method used. With a ring, it still returns the count since the last call, as counts are incremented in tpacket_rcv and reset in getsockopt. Without a ring, it returns 0 if no drops occurred since the last getsockopt and the total drops over the lifespan of the socket otherwise. The culprit is this line in packet_rcv, executed on a drop: drop_n_acct: po->stats.tp_drops = atomic_inc_return(&sk->sk_drops); As it shows, the new drop number it taken from the socket drop counter, which is not reset at getsockopt. I put together a small example that demonstrates the issue [2]. It runs for 10 seconds and overflows the queue/ring on every odd second. The reported drop rates are: ring: 16, 0, 16, 0, 16, ... non-ring: 0, 15, 0, 30, 0, 46, 0, 60, 0 , 74. Note how the even ring counts monotonically increase. Because the getsockopt adds tp_drops to tp_packets, total counts are similarly reported cumulatively. Long story short, reinstating the original code, as the below patch does, fixes the issue at the cost of additional per-packet cycles. Another solution that does not introduce per-packet overhead is be to keep the current data path, record the value of sk_drops at getsockopt() at call N in a new field in struct packetsock and subtract that when reporting at call N+1. I'll be happy to code that, instead, it's just more messy. [1] http://patchwork.ozlabs.org/patch/35665/ [2] http://kernel.googlecode.com/files/test-packetsock-getstatistics.cSigned-off-by: NWillem de Bruijn <willemb@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 16 9月, 2011 1 次提交
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由 Jiri Pirko 提交于
This patch does several things: - introduces __ethtool_get_settings which is called from ethtool code and from drivers as well. Put ASSERT_RTNL there. - dev_ethtool_get_settings() is replaced by __ethtool_get_settings() - changes calling in drivers so rtnl locking is respected. In iboe_get_rate was previously ->get_settings() called unlocked. This fixes it. Also prb_calc_retire_blk_tmo() in af_packet.c had the same problem. Also fixed by calling __dev_get_by_index() instead of dev_get_by_index() and holding rtnl_lock for both calls. - introduces rtnl_lock in bnx2fc_vport_create() and fcoe_vport_create() so bnx2fc_if_create() and fcoe_if_create() are called locked as they are from other places. - use __ethtool_get_settings() in bonding code Signed-off-by: NJiri Pirko <jpirko@redhat.com> v2->v3: -removed dev_ethtool_get_settings() -added ASSERT_RTNL into __ethtool_get_settings() -prb_calc_retire_blk_tmo - use __dev_get_by_index() and lock around it and __ethtool_get_settings() call v1->v2: add missing export_symbol Reviewed-by: Ben Hutchings <bhutchings@solarflare.com> [except FCoE bits] Acked-by: NRalf Baechle <ralf@linux-mips.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 27 8月, 2011 1 次提交
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由 chetan loke 提交于
structs introduced in tpacket_v3 implementation are prefixed with 'tpacket' to avoid namespace collision. Compile tested. Signed-off-by: NChetan Loke <loke.chetan@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 25 8月, 2011 1 次提交
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由 chetan loke 提交于
1) Blocks can be configured with non-static frame-size. 2) Read/poll is at a block-level(as opposed to packet-level). 3) Added poll timeout to avoid indefinite user-space wait on idle links. 4) Added user-configurable knobs: 4.1) block::timeout. 4.2) tpkt_hdr::sk_rxhash. Changes: C1) tpacket_rcv() C1.1) packet_current_frame() is replaced by packet_current_rx_frame() The bulk of the processing is then moved in the following chain: packet_current_rx_frame() __packet_lookup_frame_in_block fill_curr_block() or retire_current_block dispatch_next_block or return NULL(queue is plugged/paused) Signed-off-by: NChetan Loke <loke.chetan@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 14 7月, 2011 1 次提交
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由 Chetan Loke 提交于
Currently we flush tp_status and then flush the remainder of the header+payload. tp_status should be flushed in the end to avoid stale data being read by user-space. Incorrectly re-ordered barriers in v1. Signed-off-by: NChetan Loke <loke.chetan@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 07 7月, 2011 2 次提交
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由 David S. Miller 提交于
af_packet.c:(.text+0x3d130): undefined reference to `ip_defrag' or ERROR: "ip_defrag" [net/packet/af_packet.ko] undefined! Reported-by: NRandy Dunlap <randy.dunlap@oracle.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Eric Dumazet 提交于
fanout_add() might return with fanout_mutex held. Reduce indentation level while we are at it Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 06 7月, 2011 5 次提交
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由 David S. Miller 提交于
When we clone the SKB, we forget about the original one. Avoid this problem by using skb_share_check(). Reported-by: NPenttilä Mika <mika.penttila@ixonos.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 David S. Miller 提交于
Unfortunately we have to use a real modulus here as the multiply trick won't work as effectively with cpu numbers as it does with rxhash values. Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 David S. Miller 提交于
The skb->rxhash cannot be properly computed if the packet is a fragment. To alleviate this, allow the AF_PACKET client to ask for defragmentation to be done at demux time. Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 David S. Miller 提交于
Fanouts allow packet capturing to be demuxed to a set of AF_PACKET sockets. Two fanout policies are implemented: 1) Hashing based upon skb->rxhash 2) Pure round-robin An AF_PACKET socket must be fully bound before it tries to add itself to a fanout. All AF_PACKET sockets trying to join the same fanout must all have the same bind settings. Fanouts are identified (within a network namespace) by a 16-bit ID. The first socket to try to add itself to a fanout with a particular ID, creates that fanout. When the last socket leaves the fanout (which happens only when the socket is closed), that fanout is destroyed. Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 David S. Miller 提交于
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 12 6月, 2011 1 次提交
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由 Jason Wang 提交于
There's no need for the guest to validate the checksum if it have been validated by host nics. So this patch introduces a new flag - VIRTIO_NET_HDR_F_DATA_VALID which is used to bypass the checksum examing in guest. The backend (tap/macvtap) may set this flag when met skbs with CHECKSUM_UNNECESSARY to save cpu utilization. No feature negotiation is needed as old driver just ignore this flag. Iperf shows 12%-30% performance improvement for UDP traffic. For TCP, when gro is on no difference as it produces skb with partial checksum. But when gro is disabled, 20% or even higher improvement could be measured by netperf. Signed-off-by: NJason Wang <jasowang@redhat.com> Acked-by: NMichael S. Tsirkin <mst@redhat.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 07 6月, 2011 1 次提交
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由 Eric Dumazet 提交于
In 2.6.27, commit 393e52e3 (packet: deliver VLAN TCI to userspace) added a small information leak. Add padding field and make sure its zeroed before copy to user. Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com> CC: Patrick McHardy <kaber@trash.net> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 06 6月, 2011 2 次提交
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由 Ben Greear 提交于
This saves a network device lookup on each packet transmitted, for sockets that are bound to a network device. Signed-off-by: NBen Greear <greearb@candelatech.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Ben Greear 提交于
Old code was probably safe, but with this change we can actually use the netdev object, not just compare the pointer values. Signed-off-by: NBen Greear <greearb@candelatech.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 02 6月, 2011 1 次提交
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由 Ben Greear 提交于
Currently, user-space cannot determine if a 0 tcp_vlan_tci means there is no VLAN tag or the VLAN ID was zero. Add flag to make this explicit. User-space can check for TP_STATUS_VLAN_VALID || tp_vlan_tci > 0, which will be backwards compatible. Older could would have just checked for tp_vlan_tci, so it will work no worse than before. Signed-off-by: NBen Greear <greearb@candelatech.com> Acked-by: NEric Dumazet <eric.dumazet@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 24 5月, 2011 1 次提交
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由 Dan Rosenberg 提交于
The %pK format specifier is designed to hide exposed kernel pointers, specifically via /proc interfaces. Exposing these pointers provides an easy target for kernel write vulnerabilities, since they reveal the locations of writable structures containing easily triggerable function pointers. The behavior of %pK depends on the kptr_restrict sysctl. If kptr_restrict is set to 0, no deviation from the standard %p behavior occurs. If kptr_restrict is set to 1, the default, if the current user (intended to be a reader via seq_printf(), etc.) does not have CAP_SYSLOG (currently in the LSM tree), kernel pointers using %pK are printed as 0's. If kptr_restrict is set to 2, kernel pointers using %pK are printed as 0's regardless of privileges. Replacing with 0's was chosen over the default "(null)", which cannot be parsed by userland %p, which expects "(nil)". The supporting code for kptr_restrict and %pK are currently in the -mm tree. This patch converts users of %p in net/ to %pK. Cases of printing pointers to the syslog are not covered, since this would eliminate useful information for postmortem debugging and the reading of the syslog is already optionally protected by the dmesg_restrict sysctl. Signed-off-by: NDan Rosenberg <drosenberg@vsecurity.com> Cc: James Morris <jmorris@namei.org> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Thomas Graf <tgraf@infradead.org> Cc: Eugene Teo <eugeneteo@kernel.org> Cc: Kees Cook <kees.cook@canonical.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: David S. Miller <davem@davemloft.net> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Eric Paris <eparis@parisplace.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 28 4月, 2011 1 次提交
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由 Eric Dumazet 提交于
In order to speedup packet filtering, here is an implementation of a JIT compiler for x86_64 It is disabled by default, and must be enabled by the admin. echo 1 >/proc/sys/net/core/bpf_jit_enable It uses module_alloc() and module_free() to get memory in the 2GB text kernel range since we call helpers functions from the generated code. EAX : BPF A accumulator EBX : BPF X accumulator RDI : pointer to skb (first argument given to JIT function) RBP : frame pointer (even if CONFIG_FRAME_POINTER=n) r9d : skb->len - skb->data_len (headlen) r8 : skb->data To get a trace of generated code, use : echo 2 >/proc/sys/net/core/bpf_jit_enable Example of generated code : # tcpdump -p -n -s 0 -i eth1 host 192.168.20.0/24 flen=18 proglen=147 pass=3 image=ffffffffa00b5000 JIT code: ffffffffa00b5000: 55 48 89 e5 48 83 ec 60 48 89 5d f8 44 8b 4f 60 JIT code: ffffffffa00b5010: 44 2b 4f 64 4c 8b 87 b8 00 00 00 be 0c 00 00 00 JIT code: ffffffffa00b5020: e8 24 7b f7 e0 3d 00 08 00 00 75 28 be 1a 00 00 JIT code: ffffffffa00b5030: 00 e8 fe 7a f7 e0 24 00 3d 00 14 a8 c0 74 49 be JIT code: ffffffffa00b5040: 1e 00 00 00 e8 eb 7a f7 e0 24 00 3d 00 14 a8 c0 JIT code: ffffffffa00b5050: 74 36 eb 3b 3d 06 08 00 00 74 07 3d 35 80 00 00 JIT code: ffffffffa00b5060: 75 2d be 1c 00 00 00 e8 c8 7a f7 e0 24 00 3d 00 JIT code: ffffffffa00b5070: 14 a8 c0 74 13 be 26 00 00 00 e8 b5 7a f7 e0 24 JIT code: ffffffffa00b5080: 00 3d 00 14 a8 c0 75 07 b8 ff ff 00 00 eb 02 31 JIT code: ffffffffa00b5090: c0 c9 c3 BPF program is 144 bytes long, so native program is almost same size ;) (000) ldh [12] (001) jeq #0x800 jt 2 jf 8 (002) ld [26] (003) and #0xffffff00 (004) jeq #0xc0a81400 jt 16 jf 5 (005) ld [30] (006) and #0xffffff00 (007) jeq #0xc0a81400 jt 16 jf 17 (008) jeq #0x806 jt 10 jf 9 (009) jeq #0x8035 jt 10 jf 17 (010) ld [28] (011) and #0xffffff00 (012) jeq #0xc0a81400 jt 16 jf 13 (013) ld [38] (014) and #0xffffff00 (015) jeq #0xc0a81400 jt 16 jf 17 (016) ret #65535 (017) ret #0 Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Ben Hutchings <bhutchings@solarflare.com> Cc: Hagen Paul Pfeifer <hagen@jauu.net> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 08 3月, 2011 1 次提交
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由 Hagen Paul Pfeifer 提交于
Signed-off-by: NHagen Paul Pfeifer <hagen@jauu.net> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 12 2月, 2011 1 次提交
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由 Ben Greear 提交于
This allows user-space to send a '1500' MTU VLAN packet on a 1500 MTU ethernet frame. The extra 4 bytes of a VLAN header is not usually charged against the MTU when other parts of the network stack is transmitting vlans... Signed-off-by: NBen Greear <greearb@candelatech.com> Reviewed-by: NEric Dumazet <eric.dumazet@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 20 1月, 2011 1 次提交
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由 Shan Wei 提交于
Clean up some unused macros in net/*. 1. be left for code change. e.g. PGV_FROM_VMALLOC, PGV_FROM_VMALLOC, KMEM_SAFETYZONE. 2. never be used since introduced to kernel. e.g. P9_RDMA_MAX_SGE, UTIL_CTRL_PKT_SIZE. Signed-off-by: NShan Wei <shanwei@cn.fujitsu.com> Acked-by: NSjur Braendeland <sjur.brandeland@stericsson.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 19 1月, 2011 1 次提交
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由 Eric Dumazet 提交于
Packet filter (BPF) doesnt need to disable softirqs, being fully re-entrant and lock-less. Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 17 12月, 2010 1 次提交
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由 Michał Mirosław 提交于
Replace skb->csum_start - skb_headroom(skb) with skb_checksum_start_offset(). Note for usb/smsc95xx: skb->data - skb->head == skb_headroom(skb). Signed-off-by: NMichał Mirosław <mirq-linux@rere.qmqm.pl> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 11 12月, 2010 1 次提交
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由 Changli Gao 提交于
Signed-off-by: NChangli Gao <xiaosuo@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 09 12月, 2010 3 次提交
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由 Changli Gao 提交于
It is introduced in: commit 0e3125c7 Author: Neil Horman <nhorman@tuxdriver.com> Date: Tue Nov 16 10:26:47 2010 -0800 packet: Enhance AF_PACKET implementation to not require high order contiguous memory allocation (v4) Signed-off-by: NChangli Gao <xiaosuo@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Changli Gao 提交于
Some arches don't need flush_dcache_page(), and don't implement it, so we can eliminate pgv_to_page() calls on those arches. Signed-off-by: NChangli Gao <xiaosuo@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Eric Dumazet 提交于
sk_run_filter() doesnt write on skb, change its prototype to reflect this. Fix two af_packet comments. Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 07 12月, 2010 2 次提交
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由 Changli Gao 提交于
As we can check if an address is vmalloc address with is_vmalloc_addr(), we remove pgv.flags. Then we may get more pg_vecs. Signed-off-by: NChangli Gao <xiaosuo@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Changli Gao 提交于
The following commit causes the pgv->buffer may point to the memory returned by vmalloc(). And we can't use virt_to_page() for the vmalloc address. This patch introduces a new inline function pgv_to_page(), which calls vmalloc_to_page() for the vmalloc address, and virt_to_page() for the __get_free_pages address. We used to increase page pointer to get the next page at the next page address, after Neil's patch, it is wrong, as the physical address may be not continuous. This patch also fixes this issue. commit 0e3125c7 Author: Neil Horman <nhorman@tuxdriver.com> Date: Tue Nov 16 10:26:47 2010 -0800 packet: Enhance AF_PACKET implementation to not require high order contiguous memory allocation (v4) Signed-off-by: NChangli Gao <xiaosuo@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 22 11月, 2010 1 次提交
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由 Eric Dumazet 提交于
alloc_one_pg_vec_page() is supposed to return zeroed memory, so use vzalloc() instead of vmalloc() Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com> Cc: Neil Horman <nhorman@tuxdriver.com> Acked-by: NNeil Horman <nhorman@tuxdriver.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 20 11月, 2010 1 次提交
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由 Eric Dumazet 提交于
Remove pc variable to avoid arithmetic to compute fentry at each filter instruction. Jumps directly manipulate fentry pointer. As the last instruction of filter[] is guaranteed to be a RETURN, and all jumps are before the last instruction, we dont need to check filter bounds (number of instructions in filter array) at each iteration, so we remove it from sk_run_filter() params. On x86_32 remove f_k var introduced in commit 57fe93b3 (filter: make sure filters dont read uninitialized memory) Note : We could use a CONFIG_ARCH_HAS_{FEW|MANY}_REGISTERS in order to avoid too many ifdefs in this code. This helps compiler to use cpu registers to hold fentry and A accumulator. On x86_32, this saves 401 bytes, and more important, sk_run_filter() runs much faster because less register pressure (One less conditional branch per BPF instruction) # size net/core/filter.o net/core/filter_pre.o text data bss dec hex filename 2948 0 0 2948 b84 net/core/filter.o 3349 0 0 3349 d15 net/core/filter_pre.o on x86_64 : # size net/core/filter.o net/core/filter_pre.o text data bss dec hex filename 5173 0 0 5173 1435 net/core/filter.o 5224 0 0 5224 1468 net/core/filter_pre.o Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com> Acked-by: NChangli Gao <xiaosuo@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 17 11月, 2010 1 次提交
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由 Neil Horman 提交于
packet: Enhance AF_PACKET implementation to not require high order contiguous memory allocation (v4) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Version 4 of this patch. Change notes: 1) Removed extra memset. Didn't think kcalloc added a GFP_ZERO the way kzalloc did :) Summary: It was shown to me recently that systems under high load were driven very deep into swap when tcpdump was run. The reason this happened was because the AF_PACKET protocol has a SET_RINGBUFFER socket option that allows the user space application to specify how many entries an AF_PACKET socket will have and how large each entry will be. It seems the default setting for tcpdump is to set the ring buffer to 32 entries of 64 Kb each, which implies 32 order 5 allocation. Thats difficult under good circumstances, and horrid under memory pressure. I thought it would be good to make that a bit more usable. I was going to do a simple conversion of the ring buffer from contigous pages to iovecs, but unfortunately, the metadata which AF_PACKET places in these buffers can easily span a page boundary, and given that these buffers get mapped into user space, and the data layout doesn't easily allow for a change to padding between frames to avoid that, a simple iovec change is just going to break user space ABI consistency. So I've done this, I've added a three tiered mechanism to the af_packet set_ring socket option. It attempts to allocate memory in the following order: 1) Using __get_free_pages with GFP_NORETRY set, so as to fail quickly without digging into swap 2) Using vmalloc 3) Using __get_free_pages with GFP_NORETRY clear, causing us to try as hard as needed to get the memory The effect is that we don't disturb the system as much when we're under load, while still being able to conduct tcpdumps effectively. Tested successfully by me. Signed-off-by: NNeil Horman <nhorman@tuxdriver.com> Acked-by: NEric Dumazet <eric.dumazet@gmail.com> Acked-by: NMaciej Żenczykowski <zenczykowski@gmail.com> Reported-by: NMaciej Żenczykowski <zenczykowski@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 13 11月, 2010 1 次提交
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由 Mariusz Kozlowski 提交于
Parameter 'len' is size_t type so it will never get negative. Signed-off-by: NMariusz Kozlowski <mk@lab.zgora.pl> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 11 11月, 2010 1 次提交
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由 Vasiliy Kulikov 提交于
packet_getname_spkt() doesn't initialize all members of sa_data field of sockaddr struct if strlen(dev->name) < 13. This structure is then copied to userland. It leads to leaking of contents of kernel stack memory. We have to fully fill sa_data with strncpy() instead of strlcpy(). The same with packet_getname(): it doesn't initialize sll_pkttype field of sockaddr_ll. Set it to zero. Signed-off-by: NVasiliy Kulikov <segooon@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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