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Diffstat (limited to 'Documentation/networking/packet_mmap.rst')
| -rw-r--r-- | Documentation/networking/packet_mmap.rst | 21 |
1 files changed, 11 insertions, 10 deletions
diff --git a/Documentation/networking/packet_mmap.rst b/Documentation/networking/packet_mmap.rst index c5da1a5d93de..02370786e77b 100644 --- a/Documentation/networking/packet_mmap.rst +++ b/Documentation/networking/packet_mmap.rst @@ -16,7 +16,7 @@ ii) transmit network traffic, or any other that needs raw Howto can be found at: - https://sites.google.com/site/packetmmap/ + https://web.archive.org/web/20220404160947/https://sites.google.com/site/packetmmap/ Please send your comments to - Ulisses Alonso Camaró <uaca@i.hate.spam.alumni.uv.es> @@ -166,7 +166,8 @@ As capture, each frame contains two parts:: /* bind socket to eth0 */ bind(this->socket, (struct sockaddr *)&my_addr, sizeof(struct sockaddr_ll)); - A complete tutorial is available at: https://sites.google.com/site/packetmmap/ + A complete tutorial is available at: + https://web.archive.org/web/20220404160947/https://sites.google.com/site/packetmmap/ By default, the user should put data at:: @@ -263,20 +264,20 @@ the name indicates, this function allocates pages of memory, and the second argument is "order" or a power of two number of pages, that is (for PAGE_SIZE == 4096) order=0 ==> 4096 bytes, order=1 ==> 8192 bytes, order=2 ==> 16384 bytes, etc. The maximum size of a -region allocated by __get_free_pages is determined by the MAX_ORDER macro. More -precisely the limit can be calculated as:: +region allocated by __get_free_pages is determined by the MAX_PAGE_ORDER macro. +More precisely the limit can be calculated as:: - PAGE_SIZE << MAX_ORDER + PAGE_SIZE << MAX_PAGE_ORDER In a i386 architecture PAGE_SIZE is 4096 bytes - In a 2.4/i386 kernel MAX_ORDER is 10 - In a 2.6/i386 kernel MAX_ORDER is 11 + In a 2.4/i386 kernel MAX_PAGE_ORDER is 10 + In a 2.6/i386 kernel MAX_PAGE_ORDER is 11 So get_free_pages can allocate as much as 4MB or 8MB in a 2.4/2.6 kernel respectively, with an i386 architecture. User space programs can include /usr/include/sys/user.h and -/usr/include/linux/mmzone.h to get PAGE_SIZE MAX_ORDER declarations. +/usr/include/linux/mmzone.h to get PAGE_SIZE MAX_PAGE_ORDER declarations. The pagesize can also be determined dynamically with the getpagesize (2) system call. @@ -324,7 +325,7 @@ Definitions: (see /proc/slabinfo) <pointer size> depends on the architecture -- ``sizeof(void *)`` <page size> depends on the architecture -- PAGE_SIZE or getpagesize (2) -<max-order> is the value defined with MAX_ORDER +<max-order> is the value defined with MAX_PAGE_ORDER <frame size> it's an upper bound of frame's capture size (more on this later) ============== ================================================================ @@ -755,7 +756,7 @@ AF_PACKET TPACKET_V3 example ============================ AF_PACKET's TPACKET_V3 ring buffer can be configured to use non-static frame -sizes by doing it's own memory management. It is based on blocks where polling +sizes by doing its own memory management. It is based on blocks where polling works on a per block basis instead of per ring as in TPACKET_V2 and predecessor. It is said that TPACKET_V3 brings the following benefits: |