Hi, Request you to check if the memory allocation is done using GFP_DMA in kmalloc ??? Thanks Sekhar 2010/10/20 Trübenbach, Ralf <Ralf.Truebenbach@xxxxxx>: > Hello, > > I have a problem with our VME driver (sources see below) and high > memory. I would like to transfer the content of a user space alloced > buffer to another VME device using DMA (see vme4l-core.c->vme4l_zc_dma()). > The actual driver version uses page_address() and virt_to_bus() to get > the bus addresses needed to fill the DMA scatter list. Unfortunately > this is not working with highmem. > > I tried with page_to_phys() instead of page_address/virt_to_bus which > seems to work. But is this correct for all architectures? As far as I > understood I have to use the bus addresses and not the physical > addresses to fill the DMA scatter list. > > Maybe someone knows an example where I can have a look at, or any other > suggestions? > > Thank you, > > Ralf > > > Sources: > -------- > http://codeviewer.org/view/code:12ed vme4l-core.c > http://codeviewer.org/view/code:12ee vme4l-tsi148.c > http://codeviewer.org/view/code:12ef vme4l-tsi148.h > http://codeviewer.org/view/code:12f0 vme4l-menpldz002.c > http://codeviewer.org/view/code:12f1 vme4l-core.h > or (complete): > http://www.men.de/download/free/13z014-90/13z014-90_02_11.zip > > Best Regards/Mit freundlichen Gruessen > > Ralf Trübenbach > > ------------------------------------------------------------------------ > > Ralf Trübenbach, Software Design > MEN Mikro Elektronik GmbH > Neuwieder Straße 5-7 > 90411 Nürnberg, Germany > Phone +49-911-99 33 5-0 > Fax +49-911-99 33 5-910 > Ralf.Truebenbach@xxxxxx > www.men.de > > > > MEN Mikro Elektronik GmbH - Manfred Schmitz (CTO), Udo Fuchs (CFO) > - Handelsregister/Trade Register AG Nürnberg HRB 5540 > > > > -- > To unsubscribe from this list: send an email with > "unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx > Please read the FAQ at http://kernelnewbies.org/FAQ > > -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx Please read the FAQ at http://kernelnewbies.org/FAQ