From 253007d14712fb172a59f164fe5828565e2af112 Mon Sep 17 00:00:00 2001 From: Jagannathan Raman Date: Mon, 13 Jun 2022 16:26:30 -0400 Subject: [PATCH] vfio-user: IOMMU support for remote device Assign separate address space for each device in the remote processes. Signed-off-by: Elena Ufimtseva Signed-off-by: John G Johnson Signed-off-by: Jagannathan Raman Reviewed-by: Stefan Hajnoczi Message-id: afe0b0a97582cdad42b5b25636a29c523265a10a.1655151679.git.jag.raman@oracle.com Signed-off-by: Stefan Hajnoczi --- MAINTAINERS | 2 + hw/remote/iommu.c | 131 ++++++++++++++++++++++++++++++++++++++ hw/remote/machine.c | 13 +++- hw/remote/meson.build | 1 + include/hw/remote/iommu.h | 40 ++++++++++++ 5 files changed, 186 insertions(+), 1 deletion(-) create mode 100644 hw/remote/iommu.c create mode 100644 include/hw/remote/iommu.h diff --git a/MAINTAINERS b/MAINTAINERS index cbac72e239..563259101b 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -3644,6 +3644,8 @@ F: hw/remote/iohub.c F: include/hw/remote/iohub.h F: subprojects/libvfio-user F: hw/remote/vfio-user-obj.c +F: hw/remote/iommu.c +F: include/hw/remote/iommu.h EBPF: M: Jason Wang diff --git a/hw/remote/iommu.c b/hw/remote/iommu.c new file mode 100644 index 0000000000..fd723d91f3 --- /dev/null +++ b/hw/remote/iommu.c @@ -0,0 +1,131 @@ +/** + * IOMMU for remote device + * + * Copyright © 2022 Oracle and/or its affiliates. + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + * + */ + +#include "qemu/osdep.h" + +#include "hw/remote/iommu.h" +#include "hw/pci/pci_bus.h" +#include "hw/pci/pci.h" +#include "exec/memory.h" +#include "exec/address-spaces.h" +#include "trace.h" + +/** + * IOMMU for TYPE_REMOTE_MACHINE - manages DMA address space isolation + * for remote machine. It is used by TYPE_VFIO_USER_SERVER. + * + * - Each TYPE_VFIO_USER_SERVER instance handles one PCIDevice on a PCIBus. + * There is one RemoteIommu per PCIBus, so the RemoteIommu tracks multiple + * PCIDevices by maintaining a ->elem_by_devfn mapping. + * + * - memory_region_init_iommu() is not used because vfio-user MemoryRegions + * will be added to the elem->mr container instead. This is more natural + * than implementing the IOMMUMemoryRegionClass APIs since vfio-user + * provides something that is close to a full-fledged MemoryRegion and + * not like an IOMMU mapping. + * + * - When a device is hot unplugged, the elem->mr reference is dropped so + * all vfio-user MemoryRegions associated with this vfio-user server are + * destroyed. + */ + +static AddressSpace *remote_iommu_find_add_as(PCIBus *pci_bus, + void *opaque, int devfn) +{ + RemoteIommu *iommu = opaque; + RemoteIommuElem *elem = NULL; + + qemu_mutex_lock(&iommu->lock); + + elem = g_hash_table_lookup(iommu->elem_by_devfn, INT2VOIDP(devfn)); + + if (!elem) { + elem = g_malloc0(sizeof(RemoteIommuElem)); + g_hash_table_insert(iommu->elem_by_devfn, INT2VOIDP(devfn), elem); + } + + if (!elem->mr) { + elem->mr = MEMORY_REGION(object_new(TYPE_MEMORY_REGION)); + memory_region_set_size(elem->mr, UINT64_MAX); + address_space_init(&elem->as, elem->mr, NULL); + } + + qemu_mutex_unlock(&iommu->lock); + + return &elem->as; +} + +void remote_iommu_unplug_dev(PCIDevice *pci_dev) +{ + AddressSpace *as = pci_device_iommu_address_space(pci_dev); + RemoteIommuElem *elem = NULL; + + if (as == &address_space_memory) { + return; + } + + elem = container_of(as, RemoteIommuElem, as); + + address_space_destroy(&elem->as); + + object_unref(elem->mr); + + elem->mr = NULL; +} + +static void remote_iommu_init(Object *obj) +{ + RemoteIommu *iommu = REMOTE_IOMMU(obj); + + iommu->elem_by_devfn = g_hash_table_new_full(NULL, NULL, NULL, g_free); + + qemu_mutex_init(&iommu->lock); +} + +static void remote_iommu_finalize(Object *obj) +{ + RemoteIommu *iommu = REMOTE_IOMMU(obj); + + qemu_mutex_destroy(&iommu->lock); + + g_hash_table_destroy(iommu->elem_by_devfn); + + iommu->elem_by_devfn = NULL; +} + +void remote_iommu_setup(PCIBus *pci_bus) +{ + RemoteIommu *iommu = NULL; + + g_assert(pci_bus); + + iommu = REMOTE_IOMMU(object_new(TYPE_REMOTE_IOMMU)); + + pci_setup_iommu(pci_bus, remote_iommu_find_add_as, iommu); + + object_property_add_child(OBJECT(pci_bus), "remote-iommu", OBJECT(iommu)); + + object_unref(OBJECT(iommu)); +} + +static const TypeInfo remote_iommu_info = { + .name = TYPE_REMOTE_IOMMU, + .parent = TYPE_OBJECT, + .instance_size = sizeof(RemoteIommu), + .instance_init = remote_iommu_init, + .instance_finalize = remote_iommu_finalize, +}; + +static void remote_iommu_register_types(void) +{ + type_register_static(&remote_iommu_info); +} + +type_init(remote_iommu_register_types) diff --git a/hw/remote/machine.c b/hw/remote/machine.c index 4d008ed721..cbb2add291 100644 --- a/hw/remote/machine.c +++ b/hw/remote/machine.c @@ -20,6 +20,7 @@ #include "qapi/error.h" #include "hw/pci/pci_host.h" #include "hw/remote/iohub.h" +#include "hw/remote/iommu.h" #include "hw/qdev-core.h" static void remote_machine_init(MachineState *machine) @@ -99,6 +100,16 @@ static void remote_machine_instance_init(Object *obj) s->auto_shutdown = true; } +static void remote_machine_dev_unplug_cb(HotplugHandler *hotplug_dev, + DeviceState *dev, Error **errp) +{ + qdev_unrealize(dev); + + if (object_dynamic_cast(OBJECT(dev), TYPE_PCI_DEVICE)) { + remote_iommu_unplug_dev(PCI_DEVICE(dev)); + } +} + static void remote_machine_class_init(ObjectClass *oc, void *data) { MachineClass *mc = MACHINE_CLASS(oc); @@ -107,7 +118,7 @@ static void remote_machine_class_init(ObjectClass *oc, void *data) mc->init = remote_machine_init; mc->desc = "Experimental remote machine"; - hc->unplug = qdev_simple_device_unplug_cb; + hc->unplug = remote_machine_dev_unplug_cb; object_class_property_add_bool(oc, "vfio-user", remote_machine_get_vfio_user, diff --git a/hw/remote/meson.build b/hw/remote/meson.build index 0eb5a0f375..ab25c04906 100644 --- a/hw/remote/meson.build +++ b/hw/remote/meson.build @@ -6,6 +6,7 @@ remote_ss.add(when: 'CONFIG_MULTIPROCESS', if_true: files('message.c')) remote_ss.add(when: 'CONFIG_MULTIPROCESS', if_true: files('remote-obj.c')) remote_ss.add(when: 'CONFIG_MULTIPROCESS', if_true: files('proxy.c')) remote_ss.add(when: 'CONFIG_MULTIPROCESS', if_true: files('iohub.c')) +remote_ss.add(when: 'CONFIG_MULTIPROCESS', if_true: files('iommu.c')) remote_ss.add(when: 'CONFIG_VFIO_USER_SERVER', if_true: files('vfio-user-obj.c')) remote_ss.add(when: 'CONFIG_VFIO_USER_SERVER', if_true: libvfio_user_dep) diff --git a/include/hw/remote/iommu.h b/include/hw/remote/iommu.h new file mode 100644 index 0000000000..33b68a8f4b --- /dev/null +++ b/include/hw/remote/iommu.h @@ -0,0 +1,40 @@ +/** + * Copyright © 2022 Oracle and/or its affiliates. + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + * + */ + +#ifndef REMOTE_IOMMU_H +#define REMOTE_IOMMU_H + +#include "hw/pci/pci_bus.h" +#include "hw/pci/pci.h" + +#ifndef INT2VOIDP +#define INT2VOIDP(i) (void *)(uintptr_t)(i) +#endif + +typedef struct RemoteIommuElem { + MemoryRegion *mr; + + AddressSpace as; +} RemoteIommuElem; + +#define TYPE_REMOTE_IOMMU "x-remote-iommu" +OBJECT_DECLARE_SIMPLE_TYPE(RemoteIommu, REMOTE_IOMMU) + +struct RemoteIommu { + Object parent; + + GHashTable *elem_by_devfn; + + QemuMutex lock; +}; + +void remote_iommu_setup(PCIBus *pci_bus); + +void remote_iommu_unplug_dev(PCIDevice *pci_dev); + +#endif