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2018-03-16doc: remove out of date links and info from packet mmapStephen Hemminger1-17/+5
The packet_mmap documentation had links to no longer existing web sites; replace with other site which has similar example. Support for packet mmap has been in mainline versions of libpcap for several years. Signed-off-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-12Documentation: fix networking related doc refs.Tom Saeger1-1/+1
Signed-off-by: Tom Saeger <tom.saeger@oracle.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2017-01-03af_packet: TX_RING support for TPACKET_V3Sowmini Varadhan1-2/+7
Although TPACKET_V3 Rx has some benefits over TPACKET_V2 Rx, *_v3 does not currently have TX_RING support. As a result an application that wants the best perf for Tx and Rx (e.g. to handle request/response transacations) ends up needing 2 sockets, one with *_v2 for Tx and another with *_v3 for Rx. This patch enables TPACKET_V2 compatible Tx features in TPACKET_V3 so that an application can use a single descriptor to get the benefits of _v3 RX_RING and _v2 TX_RING. An application may do a block-send by first filling up multiple frames in the Tx ring and then triggering a transmit. This patch only support fixed size Tx frames for TPACKET_V3, and requires that tp_next_offset must be zero. Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-24af_packet: pass checksum validation status to the userAlexander Drozdov1-3/+10
Introduce TP_STATUS_CSUM_VALID tp_status flag to tell the af_packet user that at least the transport header checksum has been already validated. For now, the flag may be set for incoming packets only. Signed-off-by: Alexander Drozdov <al.drozdov@gmail.com> Cc: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-29packet: remove deprecated syststamp timestampWillem de Bruijn1-12/+6
No device driver will ever return an skb_shared_info structure with syststamp non-zero, so remove the branch that tests for this and optionally marks the packet timestamp as TP_STATUS_TS_SYS_HARDWARE. Do not remove the definition TP_STATUS_TS_SYS_HARDWARE, as processes may refer to it. Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-22net: doc: Update references to skb->rxhashTobias Klauser1-1/+1
In commit 61b905da33 ("net: Rename skb->rxhash to skb->hash"), skb->rxhash was renamed to skb->hash. Update references in Documentation accordingly. Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Acked-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-13packet: doc: Spelling s/than/that/Geert Uytterhoeven1-1/+1
Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org> Cc: David S. Miller <davem@davemloft.net> Cc: netdev@vger.kernel.org Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-28AF_PACKET: Add documentation for queue mapping fanout modeNeil Horman1-0/+1
Recently I added a new AF_PACKET fanout operation mode in commit 2d36097, but I forgot to document it. Add PACKET_FANOUT_QM as an available mode in the af_packet documentation. Applies to net-next. Signed-off-by: Neil Horman <nhorman@tuxdriver.com> CC: "David S. Miller" <davem@davemloft.net> CC: Daniel Borkmann <dborkman@redhat.com> Acked-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-14packet: doc: describe PACKET_MMAP with one packet socket for rx and txNorbert van Bolhuis1-0/+18
Document how to use one AF_PACKET mmap socket for RX and TX. Signed-off-by: Norbert van Bolhuis <nvbolhuis@aimvalley.nl> Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-21packet: doc: add documentation for VLAN TPID deliveryAtzm Watanabe1-2/+7
Introduce TP_STATUS_VLAN_TPID_VALID bit into the documentation. Signed-off-by: Atzm Watanabe <atzm@stratosphere.co.jp> Acked-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-10packet: introduce PACKET_QDISC_BYPASS socket optionDaniel Borkmann1-0/+21
This patch introduces a PACKET_QDISC_BYPASS socket option, that allows for using a similar xmit() function as in pktgen instead of taking the dev_queue_xmit() path. This can be very useful when PF_PACKET applications are required to be used in a similar scenario as pktgen, but with full, flexible packet payload that needs to be provided, for example. On default, nothing changes in behaviour for normal PF_PACKET TX users, so everything stays as is for applications. New users, however, can now set PACKET_QDISC_BYPASS if needed to prevent own packets from i) reentering packet_rcv() and ii) to directly push the frame to the driver. In doing so we can increase pps (here 64 byte packets) for PF_PACKET a bit: # CPUs -- QDISC_BYPASS -- qdisc path -- qdisc path[**] 1 CPU == 1,509,628 pps -- 1,208,708 -- 1,247,436 2 CPUs == 3,198,659 pps -- 2,536,012 -- 1,605,779 3 CPUs == 4,787,992 pps -- 3,788,740 -- 1,735,610 4 CPUs == 6,173,956 pps -- 4,907,799 -- 1,909,114 5 CPUs == 7,495,676 pps -- 5,956,499 -- 2,014,422 6 CPUs == 9,001,496 pps -- 7,145,064 -- 2,155,261 7 CPUs == 10,229,776 pps -- 8,190,596 -- 2,220,619 8 CPUs == 11,040,732 pps -- 9,188,544 -- 2,241,879 9 CPUs == 12,009,076 pps -- 10,275,936 -- 2,068,447 10 CPUs == 11,380,052 pps -- 11,265,337 -- 1,578,689 11 CPUs == 11,672,676 pps -- 11,845,344 -- 1,297,412 [...] 20 CPUs == 11,363,192 pps -- 11,014,933 -- 1,245,081 [**]: qdisc path with packet_rcv(), how probably most people seem to use it (hopefully not anymore if not needed) The test was done using a modified trafgen, sending a simple static 64 bytes packet, on all CPUs. The trick in the fast "qdisc path" case, is to avoid reentering packet_rcv() by setting the RAW socket protocol to zero, like: socket(PF_PACKET, SOCK_RAW, 0); Tradeoffs are documented as well in this patch, clearly, if queues are busy, we will drop more packets, tc disciplines are ignored, and these packets are not visible to taps anymore. For a pktgen like scenario, we argue that this is acceptable. The pointer to the xmit function has been placed in packet socket structure hole between cached_dev and prot_hook that is hot anyway as we're working on cached_dev in each send path. Done in joint work together with Jesper Dangaard Brouer. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-10packet: fix send path when running with proto == 0Daniel Borkmann1-0/+10
Commit e40526cb20b5 introduced a cached dev pointer, that gets hooked into register_prot_hook(), __unregister_prot_hook() to update the device used for the send path. We need to fix this up, as otherwise this will not work with sockets created with protocol = 0, plus with sll_protocol = 0 passed via sockaddr_ll when doing the bind. So instead, assign the pointer directly. The compiler can inline these helper functions automagically. While at it, also assume the cached dev fast-path as likely(), and document this variant of socket creation as it seems it is not widely used (seems not even the author of TX_RING was aware of that in his reference example [1]). Tested with reproducer from e40526cb20b5. [1] http://wiki.ipxwarzone.com/index.php5?title=Linux_packet_mmap#Example Fixes: e40526cb20b5 ("packet: fix use after free race in send path when dev is released") Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Tested-by: Salam Noureddine <noureddine@aristanetworks.com> Tested-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-30net: packet: document available fanout policiesDaniel Borkmann1-0/+8
Update documentation to add fanout policies that are available. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-08doc: packet: simplify tpacket example codeDaniel Borkmann1-105/+28
This patch simplifies the tpacket_v3 example code a bit by getting rid of unecessary macro wrappers, removing some debugging code so that it is more to the point, and also adds a header comment. Now this example code is the very minimum one needs to start from when dealing with tpacket_v3 and ~100 lines smaller than before. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-25packet: doc: update timestamping partDaniel Borkmann1-6/+35
Bring the timestamping section in sync with the implementation. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-31doc: packet: add minimal TPACKET_V3 example codeDaniel Borkmann1-0/+327
Lost in space for a long time, but it finally came back to us from some ancient code tombs. This patch adds a minimal runnable example of Linux' packet mmap(2) from Chetan Loke's TPACKET_V3. Special thanks to David S. Miller, and also Eric Leblond and Victor Julien! Cc: Eric Leblond <eric@regit.org> Cc: Victor Julien <victor@inliniac.net> Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-10doc: packet_mmap: update doc to implementation statusDaniel Borkmann1-24/+209
This improves the packet_mmap.txt document in the following ways: * Add initial information about different TPACKET versions * Add initial information about packet fanout * Add pointer to BPF document (since this also could be of interest) * 'Fix' minor, rather cosmetic things Information partially taken from related commit messages. Reported-by: Ronny Meeus <ronny.meeus@gmail.com> Signed-off-by: Daniel Borkmann <daniel.borkmann@tik.ee.ethz.ch> Cc: Ulisses Alonso Camaró <uaca@alumni.uv.es> Cc: Johann Baudy <johann.baudy@gnu-log.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-08packet: tx_ring: allow the user to choose tx data offsetPaul Chavent1-0/+13
The tx data offset of packet mmap tx ring used to be : (TPACKET2_HDRLEN - sizeof(struct sockaddr_ll)) The problem is that, with SOCK_RAW socket, the payload (14 bytes after the beginning of the user data) is misaligned. This patch allows to let the user gives an offset for it's tx data if he desires. Set sock option PACKET_TX_HAS_OFF to 1, then specify in each frame of your tx ring tp_net for SOCK_DGRAM, or tp_mac for SOCK_RAW. Signed-off-by: Paul Chavent <paul.chavent@onera.fr> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-24packet: fix typo in packet_mmap.txtWei Yongjun1-1/+1
Just fixed typo of sample code in packet_mmap.txt Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-31Fix common misspellingsLucas De Marchi1-1/+1
Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2010-08-05Merge branch 'for-next' of ↵Linus Torvalds1-2/+2
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial * 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (48 commits) Documentation: update broken web addresses. fix comment typo "choosed" -> "chosen" hostap:hostap_hw.c Fix typo in comment Fix spelling contorller -> controller in comments Kconfig.debug: FAIL_IO_TIMEOUT: typo Faul -> Fault fs/Kconfig: Fix typo Userpace -> Userspace Removing dead MACH_U300_BS26 drivers/infiniband: Remove unnecessary casts of private_data fs/ocfs2: Remove unnecessary casts of private_data libfc: use ARRAY_SIZE scsi: bfa: use ARRAY_SIZE drm: i915: use ARRAY_SIZE drm: drm_edid: use ARRAY_SIZE synclink: use ARRAY_SIZE block: cciss: use ARRAY_SIZE comment typo fixes: charater => character fix comment typos concerning "challenge" arm: plat-spear: fix typo in kerneldoc reiserfs: typo comment fix update email address ...
2010-08-04Documentation: update broken web addresses.Justin P. Mattock1-2/+2
Below you will find an updated version from the original series bunching all patches into one big patch updating broken web addresses that are located in Documentation/* Some of the addresses date as far far back as 1995 etc... so searching became a bit difficult, the best way to deal with these is to use web.archive.org to locate these addresses that are outdated. Now there are also some addresses pointing to .spec files some are located, but some(after searching on the companies site)where still no where to be found. In this case I just changed the address to the company site this way the users can contact the company and they can locate them for the users. Signed-off-by: Justin P. Mattock <justinmattock@gmail.com> Signed-off-by: Thomas Weber <weber@corscience.de> Signed-off-by: Mike Frysinger <vapier.adi@gmail.com> Cc: Paulo Marques <pmarques@grupopie.com> Cc: Randy Dunlap <rdunlap@xenotime.net> Cc: Michael Neuling <mikey@neuling.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-06-02packet_mmap: expose hw packet timestamps to network packet capture utilitiesScott McMillan1-0/+26
This patch adds a setting, PACKET_TIMESTAMP, to specify the packet timestamp source that is exported to capture utilities like tcpdump by packet_mmap. PACKET_TIMESTAMP accepts the same integer bit field as SO_TIMESTAMPING. However, only the SOF_TIMESTAMPING_SYS_HARDWARE and SOF_TIMESTAMPING_RAW_HARDWARE values are currently recognized by PACKET_TIMESTAMP. SOF_TIMESTAMPING_SYS_HARDWARE takes precedence over SOF_TIMESTAMPING_RAW_HARDWARE if both bits are set. If PACKET_TIMESTAMP is not set, a software timestamp generated inside the networking stack is used (the behavior before this setting was added). Signed-off-by: Scott McMillan <scott.a.mcmillan@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-04-23Documentation/: it's -> its where appropriateFrancis Galiegue1-2/+2
Fix obvious cases of "it's" being used when "its" was meant. Signed-off-by: Francis Galiegue <fgaliegue@gmail.com> Acked-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-02-06packet: Kill CONFIG_PACKET_MMAP.David S. Miller1-4/+4
Early on this was an experimental facility that few people other than Alexey Kuznetsov played with. Now it's a pretty fundamental thing and as people add more features to AF_PACKET sockets this config options creates ifdef spaghetti. So kill it off. Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-19net: TX_RING and packet mmapJohann Baudy1-19/+121
New packet socket feature that makes packet socket more efficient for transmission. - It reduces number of system call through a PACKET_TX_RING mechanism, based on PACKET_RX_RING (Circular buffer allocated in kernel space which is mmapped from user space). - It minimizes CPU copy using fragmented SKB (almost zero copy). Signed-off-by: Johann Baudy <johann.baudy@gnu-log.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-26Documentation cleanup: trivial misspelling, punctuation, and grammar ↵Matt LaPlante1-1/+1
corrections. Cc: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-09documentation: convert the Documentation directory to UTF-8John Anthony Kazos Jr1-1/+1
Convert files within the Documentation directory to UTF-8. Adrian Bunk: small additional fixes Signed-off-by: John Anthony Kazos Jr. <jakj@j-a-k-j.com> Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-11-30Fix typos in /Documentation : MiscMatt LaPlante1-1/+1
This patch fixes typos in various Documentation txts. The patch addresses some misc words. Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com> Acked-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-10-04Fix typos in Documentation/: 'N'-'P'Matt LaPlante1-1/+1
This patch fixes typos in various Documentation txts. The patch addresses some words starting with the letters 'N'-'P'. Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com> Acked-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-10-04Fix typos in Documentation/: 'H'-'M'Matt LaPlante1-2/+2
This patch fixes typos in various Documentation txts. The patch addresses some words starting with the letters 'H'-'M'. Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com> Acked-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-10-04Fix typos in Documentation/: 'B'-'C'Matt LaPlante1-8/+8
This patch fixes typos in various Documentation txts. This patch addresses some words starting with the letters 'B'-'C'. There are also a few grammar fixes thrown in for Randy. ;) Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com> Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-10-04Fix some typos in Documentation/: 'A'Matt LaPlante1-1/+1
This patch fixes typos in various Documentation txts. This patch addresses some words starting with the letter 'A'. Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com> Acked-by: Randy Dunlap <rdunlap@xenotime.net> Acked-by: Alan Cox <alan@redhat.com> Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-04-01fix typo "Suposse" -> "Suppose"Uwe Zeisberger1-1/+1
Signed-off-by: Uwe Zeisberger <zeisberg@informatik.uni-freiburg.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-03-24fix typos "wich" -> "which"Uwe Zeisberger1-5/+5
Signed-off-by: Uwe Zeisberger <zeisberg@informatik.uni-freiburg.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
2005-04-17Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds1-0/+399
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
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