Re: [PATCH v18 QEMU 02/18] vfio: Add function to unmap VFIO region

[Kirti Wankhede]

On 5/5/2020 11:46 AM, Philippe Mathieu-Daudé wrote:
> Hi Kirti,
>
> On 5/5/20 12:44 AM, Kirti Wankhede wrote:
> > This function will be used for migration region.
> > Migration region is mmaped when migration starts and will be unmapped 
> > when
> > migration is complete.
> >
> > Signed-off-by: Kirti Wankhede <address@hidden>
> > Reviewed-by: Neo Jia <address@hidden>
> > Reviewed-by: Cornelia Huck <address@hidden>
> > ---
> >   hw/vfio/common.c              | 20 ++++++++++++++++++++
> >   hw/vfio/trace-events          |  1 +
> >   include/hw/vfio/vfio-common.h |  1 +
> >   3 files changed, 22 insertions(+)
> >
> > diff --git a/hw/vfio/common.c b/hw/vfio/common.c
> > index 0b3593b3c0c4..4a2f0d6a2233 100644
> > --- a/hw/vfio/common.c
> > +++ b/hw/vfio/common.c
> > @@ -983,6 +983,26 @@ int vfio_region_mmap(VFIORegion *region)
> >       return 0;
> >   }
> > +void vfio_region_unmap(VFIORegion *region)
> > +{
> > +    int i;
> > +
> > +    if (!region->mem) {
> > +        return;
> > +    }
> > +
> > +    for (i = 0; i < region->nr_mmaps; i++) {
>
> I'd refactor this  block <...
> > +        
> > trace_vfio_region_unmap(memory_region_name(&region->mmaps[i].mem),
> > +                                region->mmaps[i].offset,
> > +                                region->mmaps[i].offset +
> > +                                region->mmaps[i].size - 1);
> > +        memory_region_del_subregion(region->mem, &region->mmaps[i].mem);
> > +        munmap(region->mmaps[i].mmap, region->mmaps[i].size);
> > +        object_unparent(OBJECT(&region->mmaps[i].mem));
> > +        region->mmaps[i].mmap = NULL;
>
> ...> into a helper and reuse it in vfio_region_mmap(). Well, actually 
> I'd factor it out from vfio_region_mmap() then reuse it here. Anyway 
> this is v18 so can be done later on top.

Nevermind, this is not the last version, I'll do suggested change.

> Reviewed-by: Philippe Mathieu-Daudé <address@hidden>

Thanks,
Kirti

> > +    }
> > +}
> > +
> >   void vfio_region_exit(VFIORegion *region)
> >   {
> >       int i;
> > diff --git a/hw/vfio/trace-events b/hw/vfio/trace-events
> > index b1ef55a33ffd..8cdc27946cb8 100644
> > --- a/hw/vfio/trace-events
> > +++ b/hw/vfio/trace-events
> > @@ -111,6 +111,7 @@ vfio_region_mmap(const char *name, unsigned long 
> > offset, unsigned long end) "Reg
> >   vfio_region_exit(const char *name, int index) "Device %s, region %d"
> >   vfio_region_finalize(const char *name, int index) "Device %s, region 
> > %d"
> >   vfio_region_mmaps_set_enabled(const char *name, bool enabled) 
> > "Region %s mmaps enabled: %d"
> > +vfio_region_unmap(const char *name, unsigned long offset, unsigned 
> > long end) "Region %s unmap [0x%lx - 0x%lx]"
> >   vfio_region_sparse_mmap_header(const char *name, int index, int 
> > nr_areas) "Device %s region %d: %d sparse mmap entries"
> >   vfio_region_sparse_mmap_entry(int i, unsigned long start, unsigned 
> > long end) "sparse entry %d [0x%lx - 0x%lx]"
> >   vfio_get_dev_region(const char *name, int index, uint32_t type, 
> > uint32_t subtype) "%s index %d, %08x/%0x8"
> > diff --git a/include/hw/vfio/vfio-common.h 
> > b/include/hw/vfio/vfio-common.h
> > index fd564209ac71..8d7a0fbb1046 100644
> > --- a/include/hw/vfio/vfio-common.h
> > +++ b/include/hw/vfio/vfio-common.h
> > @@ -171,6 +171,7 @@ int vfio_region_setup(Object *obj, VFIODevice 
> > *vbasedev, VFIORegion *region,
> >                         int index, const char *name);
> >   int vfio_region_mmap(VFIORegion *region);
> >   void vfio_region_mmaps_set_enabled(VFIORegion *region, bool enabled);
> > +void vfio_region_unmap(VFIORegion *region);
> >   void vfio_region_exit(VFIORegion *region);
> >   void vfio_region_finalize(VFIORegion *region);
> >   void vfio_reset_handler(void *opaque);