From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:56527) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1V7kEE-0005V2-2J for qemu-devel@nongnu.org; Fri, 09 Aug 2013 06:47:35 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1V7kE9-0000hh-8N for qemu-devel@nongnu.org; Fri, 09 Aug 2013 06:47:30 -0400 Received: from ozlabs.org ([2402:b800:7003:1:1::1]:57486) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1V7kE8-0000gI-LU for qemu-devel@nongnu.org; Fri, 09 Aug 2013 06:47:25 -0400 Date: Fri, 9 Aug 2013 20:44:07 +1000 From: David Gibson Message-ID: <20130809104407.GE2904@voom.fritz.box> References: <1376038150-14527-1-git-send-email-aik@ozlabs.ru> <5204B8F9.5050201@redhat.com> <5204BAE0.8070507@ozlabs.ru> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="cPi+lWm09sJ+d57q" Content-Disposition: inline In-Reply-To: <5204BAE0.8070507@ozlabs.ru> Subject: Re: [Qemu-devel] [PATCH v2] pci: Introduce helper to retrieve a PCI device's DMA address space List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Alexey Kardashevskiy Cc: Paolo Bonzini , Anthony Liguori , "Michael S . Tsirkin" , qemu-devel@nongnu.org --cPi+lWm09sJ+d57q Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, Aug 09, 2013 at 07:48:16PM +1000, Alexey Kardashevskiy wrote: > On 08/09/2013 07:40 PM, Paolo Bonzini wrote: > > Il 09/08/2013 10:49, Alexey Kardashevskiy ha scritto: > >> A PCI device's DMA address space (possibly an IOMMU) is returned by a > >> method on the PCIBus. At the moment that only has one caller, so the > >> method is simply open coded. We'll need another caller for VFIO, so > >> this patch introduces a helper/wrapper function. > >> > >> Signed-off-by: David Gibson > >> [aik: added inheritance from parent if iommu is not set for the curren= t bus] > >> Signed-off-by: Alexey Kardashevskiy > >> > >> --- > >> Changes: > >> v2: > >> * added inheritance, needed for a pci-bridge on spapr-ppc64 > >> * pci_iommu_as renamed to pci_device_iommu_address_space > >> --- > >> hw/pci/pci.c | 22 ++++++++++++++++------ > >> include/hw/pci/pci.h | 1 + > >> 2 files changed, 17 insertions(+), 6 deletions(-) > >> > >> diff --git a/hw/pci/pci.c b/hw/pci/pci.c > >> index 4c004f5..0072b54 100644 > >> --- a/hw/pci/pci.c > >> +++ b/hw/pci/pci.c > >> @@ -812,12 +812,7 @@ static PCIDevice *do_pci_register_device(PCIDevic= e *pci_dev, PCIBus *bus, > >> } > >> =20 > >> pci_dev->bus =3D bus; > >> - if (bus->iommu_fn) { > >> - dma_as =3D bus->iommu_fn(bus, bus->iommu_opaque, devfn); > >> - } else { > >> - /* FIXME: inherit memory region from bus creator */ > >> - dma_as =3D &address_space_memory; > >> - } > >> + dma_as =3D pci_device_iommu_address_space(pci_dev); > >> =20 > >> memory_region_init_alias(&pci_dev->bus_master_enable_region, > >> OBJECT(pci_dev), "bus master", > >> @@ -2239,6 +2234,21 @@ static void pci_device_class_init(ObjectClass *= klass, void *data) > >> k->props =3D pci_props; > >> } > >> =20 > >> +AddressSpace *pci_device_iommu_address_space(PCIDevice *dev) > >> +{ > >> + PCIBus *bus =3D PCI_BUS(dev->bus); > >> + > >> + if (bus->iommu_fn) { > >> + return bus->iommu_fn(bus, bus->iommu_opaque, dev->devfn); > >> + } > >> + > >> + if (bus->parent_dev) { > >> + return pci_device_iommu_address_space(bus->parent_dev); > >> + } > >=20 > > No, this would fail if bus->parent_dev is not NULL but not a PCI device > > either. >=20 > parent_dev is of the PCIDevice* type, how can it be not a PCI device? :-/ It will be a PCI device, though the confusion is understandable. There is a parent_dev in both PCIBus, which is always a PCI device if non-NULL, as well as a parent_dev in BusState, which can be any sort of device. If both are non-NULL they will be equal apart from type. So bus->parent_dev is safe here, bus->qbus.parent_dev would not be. --=20 David Gibson | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson --cPi+lWm09sJ+d57q Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.13 (GNU/Linux) iEYEARECAAYFAlIEx/cACgkQaILKxv3ab8ahCQCfQsgafdQYPIph2kijzt3ykBuk pgsAoIBJcjkm6h/521y3j4rDmgJCH6iz =WcUS -----END PGP SIGNATURE----- --cPi+lWm09sJ+d57q--