Hi Randy, On Thu, Oct 13, 2011 at 4:00 AM, Randy Dunlap <rdunlap@xxxxxxxxxxxx> wrote: > On 10/11/2011 02:23 AM, Sumit Semwal wrote: >> Add documentation for dma buffer sharing framework, explaining the >> various operations, members and API of the dma buffer sharing >> framework. >> >> Signed-off-by: Sumit Semwal <sumit.semwal@xxxxxxxxxx> >> Signed-off-by: Sumit Semwal <sumit.semwal@xxxxxx> >> --- >> Documentation/dma-buf-sharing.txt | 210 +++++++++++++++++++++++++++++++++++++ <snip> >> + if the new buffer-user has stricter 'backing-storage constraints', and the >> + exporter can handle these constraints, the exporter can just stall on the >> + get_scatterlist till all outstanding access is completed (as signalled by > > until > Thanks for your review; I will update all these in the next version. >> + put_scatterlist). >> + Once all ongoing access is completed, the exporter could potentially move >> + the buffer to the stricter backing-storage, and then allow further >> + {get,put}_scatterlist operations from any buffer-user from the migrated >> + backing-storage. >> + >> + If the exporter cannot fulfill the backing-storage constraints of the new >> + buffer-user device as requested, dma_buf_attach() would return an error to >> + denote non-compatibility of the new buffer-sharing request with the current >> + buffer. >> + >> + If the exporter chooses not to allow an attach() operation once a >> + get_scatterlist has been called, it simply returns an error. >> + >> +- mmap file operation >> + An mmap() file operation is provided for the fd associated with the buffer. >> + If the exporter defines an mmap operation, the mmap() fop calls this to allow >> + mmap for devices that might need it; if not, it returns an error. >> + >> +References: >> +[1] struct dma_buf_ops in include/linux/dma-buf.h >> +[2] All interfaces mentioned above defined in include/linux/dma-buf.h > > > -- > ~Randy > *** Remember to use Documentation/SubmitChecklist when testing your code *** > Best regards, ~Sumit. _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel