It seems the best solution is to split large buffers when they reach the driver, for the reason that if your hardware had a much smaller maximum, you would not want to change it globally, so why should you change it globally for 32kB? > -----Original Message----- > From: Alan Shih [mailto:alan@storlinksemi.com] > Sent: Tuesday, July 22, 2003 10:54 AM > To: Eble, Dan > Subject: RE: Limit skb to be less than 64K with TSO > > > Dan, > > Thanks for your reply. I am writing a driver (+ firmware on > a smart NIC). > The SKB's comes from upper layers. TSO is tcp/ip > segmentation offloading > that 2.6 supports. > > The problem comes in when TSO is on, the system throws me 64K > SKB's maximum > which my hardware cannot take. There seems to be a few > places I can tap in > but not quite sure which method is appropriate (may be not > doable other than > my ignorance). > > 1. at alloc_skb (if I limit at 32K, I may break applications?) > 2. when I receive skb from queue_xmit, the driver needs to > break it up. > 3. figure out where in VFS that allow 64K and size it down. > > TIA > > Alan > > -----Original Message----- > From: Eble, Dan [mailto:DanE@aiinet.com] > Sent: Tuesday, July 22, 2003 5:19 AM > To: 'Alan Shih' > Subject: RE: Limit skb to be less than 64K with TSO > > > I don't know what TSO is, but I'd like to try to help, so if you could > please explain the origin of these skbs that concern you, I > would have a > clearer picture of what's going on. Are these skbs allocated > by higher > layers of the kernel networking code and passed to your driver for > transmission? > > > -----Original Message----- > > From: Alan Shih [mailto:alan@storlinksemi.com] > > Sent: Monday, July 21, 2003 10:21 PM > > To: linux-net@vger.kernel.org > > Subject: Limit skb to be less than 64K with TSO > > > > > > Hi all, > > > > Is there a way to limit skb to be 32KB Max? I am working with > > a hardware > > that has a small scratch SRAM for a smart NIC (I am using it > > to do TSO). > > It's great for speed but cannot handle large skb (>32K). > > > > TIA > > > > Alan > > > > - > > : send the line "unsubscribe > > linux-net" in > > the body of a message to majordomo@vger.kernel.org > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > > - : send the line "unsubscribe linux-net" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
