Re: [Qemu-devel] [RFC PATCH 2/8] intel_iommu: name vtd address space with devfn

["Michael S. Tsirkin" <mst@redhat.com>]

On Wed, Mar 30, 2016 at 09:12:46AM +0800, Jason Wang wrote:
> 
> 
> On 03/28/2016 10:02 AM, Peter Xu wrote:
> > On Fri, Mar 25, 2016 at 10:13:23AM +0800, Jason Wang wrote:
> >> To avoid duplicated name and ease debugging.
> >>
> >> Cc: Michael S. Tsirkin <mst@redhat.com>
> >> Cc: Paolo Bonzini <pbonzini@redhat.com>
> >> Cc: Richard Henderson <rth@twiddle.net>
> >> Cc: Eduardo Habkost <ehabkost@redhat.com>
> >> Signed-off-by: Jason Wang <jasowang@redhat.com>
> >> ---
> >>  hw/i386/intel_iommu.c | 6 ++++--
> >>  1 file changed, 4 insertions(+), 2 deletions(-)
> >>
> >> diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
> >> index 347718f..d647b42 100644
> >> --- a/hw/i386/intel_iommu.c
> >> +++ b/hw/i386/intel_iommu.c
> >> @@ -1901,6 +1901,7 @@ VTDAddressSpace *vtd_find_add_as(IntelIOMMUState *s, PCIBus *bus, int devfn)
> >>      uintptr_t key = (uintptr_t)bus;
> >>      VTDBus *vtd_bus = g_hash_table_lookup(s->vtd_as_by_busptr, &key);
> >>      VTDAddressSpace *vtd_dev_as;
> >> +    char name[128];
> >>  
> >>      if (!vtd_bus) {
> >>          /* No corresponding free() */
> >> @@ -1913,6 +1914,7 @@ VTDAddressSpace *vtd_find_add_as(IntelIOMMUState *s, PCIBus *bus, int devfn)
> >>      vtd_dev_as = vtd_bus->dev_as[devfn];
> >>  
> >>      if (!vtd_dev_as) {
> >> +        sprintf(name, "intel_iommu_devfn_%d", devfn);
> > It's safe here, but would snprintf() look better?
> 
> Not sure, we're sure that name is large enough here.

It's generally good practice, pls use snprintf.

> >
> >>          vtd_bus->dev_as[devfn] = vtd_dev_as = g_malloc0(sizeof(VTDAddressSpace));
> >>  
> >>          vtd_dev_as->bus = bus;
> >> @@ -1920,9 +1922,9 @@ VTDAddressSpace *vtd_find_add_as(IntelIOMMUState *s, PCIBus *bus, int devfn)
> >>          vtd_dev_as->iommu_state = s;
> >>          vtd_dev_as->context_cache_entry.context_cache_gen = 0;
> >>          memory_region_init_iommu(&vtd_dev_as->iommu, OBJECT(s),
> >> -                                 &s->iommu_ops, "intel_iommu", UINT64_MAX);
> >> +                                 &s->iommu_ops, name, UINT64_MAX);
> >>          address_space_init(&vtd_dev_as->as,
> >> -                           &vtd_dev_as->iommu, "intel_iommu");
> >> +                           &vtd_dev_as->iommu, name);
> >>      }
> >>      return vtd_dev_as;
> >>  }
> >> -- 
> >> 2.5.0
> >>
> > Besides the nit-pick:
> >
> > Acked-by: Peter Xu <peterx@redhat.com>
> >