Network Buffers and Memory Management
Ethernet is probably the most common physical interface type that can be handled. The kernel provides a set of general purpose Ethernet support routines that such drivers can use.
eth_header() is the standard Ethernet handler for the dev-hard_header routine, and can be used in any Ethernet driver. Combined with eth_rebuild_header() for the rebuild routine it provides all the ARP lookup required to put Ethernet headers on IP packets.
The eth_type_trans() routine expects to be fed a raw Ethernet packet. It analyses the headers and sets skb->pkt_type and skb->mac itself as well as returning the suggested value for skb->protocol. This routine is normally called from the Ethernet driver receive interrupt handler to classify packets.
eth_copy_and_sum(), the final Ethernet support routine is internally quite complex, but offers significant performance improvements for memory mapped cards. It provides the support to copy and checksum data from the card into a sk_buff in a single pass. This single pass through memory almost eliminates the cost of checksum computation when used and improves IP throughput.
Alan Cox has been working on Linux since version 0.95, when he installed it in order to do further work on the AberMUD game. He now manages the Linux Networking, SMP, and Linux/8086 projects and hasn't done any work on AberMUD since November 1993.
- Machine Learning Everywhere
- Own Your DNS Data
- Understanding OpenStack's Success
- Bash Shell Script: Building a Better March Madness Bracket
- Simple Server Hardening
- Natalie Rusk's Scratch Coding Cards (No Starch Press)
- Understanding Firewalld in Multi-Zone Configurations
- From vs. to + for Microsoft and Linux
- Returning Values from Bash Functions
- Ensono M.O.
Pick up any e-commerce web or mobile app today, and you’ll be holding a mashup of interconnected applications and services from a variety of different providers. For instance, when you connect to Amazon’s e-commerce app, cookies, tags and pixels that are monitored by solutions like Exact Target, BazaarVoice, Bing, Shopzilla, Liveramp and Google Tag Manager track every action you take. You’re presented with special offers and coupons based on your viewing and buying patterns. If you find something you want for your birthday, a third party manages your wish list, which you can share through multiple social- media outlets or email to a friend. When you select something to buy, you find yourself presented with similar items as kind suggestions. And when you finally check out, you’re offered the ability to pay with promo codes, gifts cards, PayPal or a variety of credit cards.Get the Guide