On Tue, 30 Jan 2018 10:47:14 +0100 Yi Min Zhao <zyi...@linux.vnet.ibm.com> wrote:
> The VFIO common code doesn't provide the possibility to modify a > previous mapping entry in another way than unmapping and mapping again > with new properties. I'm wondering why other architectures don't need that. Is this refreshing an unique ability on s390 (due to that instruction)? > > To avoid -EEXIST DMA mapping error, this we introduce a GHashTable to s/this// > store S390IOTLBEntry instances in order to cache the mapped entries. > When intercepting rpcit instruction, ignore the identical mapped > entries to avoid doing map operations multiple times and do unmap and > re-map operations for the case of updating the valid entries. To > achieve that goal, we also export the DMA walking function and > optimize the code handling errors in rpcit handler. How often does such a thing happen in practice? > > Acked-by: Pierre Morel <pmo...@linux.vnet.ibm.com> > Signed-off-by: Yi Min Zhao <zyi...@linux.vnet.ibm.com> > --- > hw/s390x/s390-pci-bus.c | 28 +++++++++----- > hw/s390x/s390-pci-bus.h | 3 ++ > hw/s390x/s390-pci-inst.c | 95 > ++++++++++++++++++++++++++++++++++-------------- > 3 files changed, 90 insertions(+), 36 deletions(-) Can't really review the rest due to -ENODOC, sorry.