Re: [PATCH] usbip: Implement map_urb_for_dma function for vhci to skip dma mapping

On Tue, Jun 18, 2019 at 11:30:34AM -0400, Alan Stern wrote: > On Tue, 18 Jun 2019, Suwan Kim wrote: > > > vhci doesn’t do dma for remote device. Actually, the real dma > > operation is done by network card driver. So, vhci doesn’t use and > > need dma address of transfer buffer of urb. > > > > Bu

Re: [PATCH] usbip: Implement map_urb_for_dma function for vhci to skip dma mapping

On Tue, 18 Jun 2019, Suwan Kim wrote: > vhci doesn’t do dma for remote device. Actually, the real dma > operation is done by network card driver. So, vhci doesn’t use and > need dma address of transfer buffer of urb. > > But hcd provides dma mapping function by defualt in usb_hcd_submit_urb() > a

[PATCH] usbip: Implement map_urb_for_dma function for vhci to skip dma mapping

vhci doesn’t do dma for remote device. Actually, the real dma operation is done by network card driver. So, vhci doesn’t use and need dma address of transfer buffer of urb. But hcd provides dma mapping function by defualt in usb_hcd_submit_urb() and it causes unnecessary dma mapping which will be