On Mon, Mar 21, 2016 at 01:26:58PM +0100, David Herrmann wrote: > Hi > > On Mon, Mar 21, 2016 at 8:51 AM, Daniel Vetter <daniel.vetter@xxxxxxxx> wrote: > > Just a bit of wording polish plus mentioning that it can fail and must > > be restarted. > > > > Requested by Sumit. > > > > v2: Fix them typos (Hans). > > > > Cc: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> > > Cc: Tiago Vignatti <tiago.vignatti@xxxxxxxxx> > > Cc: Stéphane Marchesin <marcheu@xxxxxxxxxxxx> > > Cc: David Herrmann <dh.herrmann@xxxxxxxxx> > > Cc: Sumit Semwal <sumit.semwal@xxxxxxxxxx> > > Cc: Daniel Vetter <daniel.vetter@xxxxxxxxx> > > CC: linux-media@xxxxxxxxxxxxxxx > > Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx > > Cc: linaro-mm-sig@xxxxxxxxxxxxxxxx > > Cc: intel-gfx@xxxxxxxxxxxxxxxxxxxxx > > Cc: devel@xxxxxxxxxxxxxxxxxxxx > > Cc: Hans Verkuil <hverkuil@xxxxxxxxx> > > Acked-by: Sumit Semwal <sumit.semwal@xxxxxxxxxx> > > Signed-off-by: Daniel Vetter <daniel.vetter@xxxxxxxxx> > > --- > > Documentation/dma-buf-sharing.txt | 11 ++++++----- > > drivers/dma-buf/dma-buf.c | 2 +- > > 2 files changed, 7 insertions(+), 6 deletions(-) > > > > diff --git a/Documentation/dma-buf-sharing.txt b/Documentation/dma-buf-sharing.txt > > index 32ac32e773e1..ca44c5820585 100644 > > --- a/Documentation/dma-buf-sharing.txt > > +++ b/Documentation/dma-buf-sharing.txt > > @@ -352,7 +352,8 @@ Being able to mmap an export dma-buf buffer object has 2 main use-cases: > > > > No special interfaces, userspace simply calls mmap on the dma-buf fd, making > > sure that the cache synchronization ioctl (DMA_BUF_IOCTL_SYNC) is *always* > > - used when the access happens. This is discussed next paragraphs. > > + used when the access happens. Note that DMA_BUF_IOCTL_SYNC can fail with > > + -EAGAIN or -EINTR, in which case it must be restarted. > > What is "restart on EAGAIN" supposed to mean? Or more generally, what > does EAGAIN tell the caller? Do what drmIoctl does essentially. while (ret == -1 && (errno == EAGAIN || errno == EINTR) ret = ioctl(); Typed from memery, too lazy to look it up in the source ;-) I'm trying to sell the idea of a real dma-buf manpage to Sumit, we should clarify this in detail there. -Daniel -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
