This patch is based on Aviv Ben-David (<bd.a...@gmail.com>)'s patch upstream:
"IOMMU: enable intel_iommu map and unmap notifiers" https://lists.gnu.org/archive/html/qemu-devel/2016-11/msg01453.html However I removed/fixed some content, and added my own codes. Instead of translate() every page for iotlb invalidations (which is slower), we walk the pages when needed and notify in a hook function. This patch enables vfio devices for VT-d emulation. And, since we already have vhost DMAR support via device-iotlb, a natural benefit that this patch brings is that vt-d enabled vhost can live even without ATS capability now. Though more tests are needed. Signed-off-by: Aviv Ben-David <bda...@cs.technion.ac.il> Reviewed-by: Jason Wang <jasow...@redhat.com> Reviewed-by: David Gibson <da...@gibson.dropbear.id.au> Signed-off-by: Peter Xu <pet...@redhat.com> --- hw/i386/intel_iommu.c | 191 ++++++++++++++++++++++++++++++++++++++--- hw/i386/intel_iommu_internal.h | 1 + hw/i386/trace-events | 1 + include/hw/i386/intel_iommu.h | 8 ++ 4 files changed, 188 insertions(+), 13 deletions(-) diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c index f7dec82..02f047c 100644 --- a/hw/i386/intel_iommu.c +++ b/hw/i386/intel_iommu.c @@ -806,7 +806,8 @@ next: * @private: private data for the hook function */ static int vtd_page_walk(VTDContextEntry *ce, uint64_t start, uint64_t end, - vtd_page_walk_hook hook_fn, void *private) + vtd_page_walk_hook hook_fn, void *private, + bool notify_unmap) { dma_addr_t addr = vtd_get_slpt_base_from_context(ce); uint32_t level = vtd_get_level_from_context_entry(ce); @@ -821,7 +822,7 @@ static int vtd_page_walk(VTDContextEntry *ce, uint64_t start, uint64_t end, } return vtd_page_walk_level(addr, start, end, hook_fn, private, - level, true, true, false); + level, true, true, notify_unmap); } /* Map a device to its corresponding domain (context-entry) */ @@ -1038,6 +1039,15 @@ static void vtd_interrupt_remap_table_setup(IntelIOMMUState *s) s->intr_root, s->intr_size); } +static void vtd_iommu_replay_all(IntelIOMMUState *s) +{ + IntelIOMMUNotifierNode *node; + + QLIST_FOREACH(node, &s->notifiers_list, next) { + memory_region_iommu_replay_all(&node->vtd_as->iommu); + } +} + static void vtd_context_global_invalidate(IntelIOMMUState *s) { trace_vtd_inv_desc_cc_global(); @@ -1045,6 +1055,14 @@ static void vtd_context_global_invalidate(IntelIOMMUState *s) if (s->context_cache_gen == VTD_CONTEXT_CACHE_GEN_MAX) { vtd_reset_context_cache(s); } + /* + * From VT-d spec 6.5.2.1, a global context entry invalidation + * should be followed by a IOTLB global invalidation, so we should + * be safe even without this. Hoewever, let's replay the region as + * well to be safer, and go back here when we need finer tunes for + * VT-d emulation codes. + */ + vtd_iommu_replay_all(s); } @@ -1111,6 +1129,16 @@ static void vtd_context_device_invalidate(IntelIOMMUState *s, trace_vtd_inv_desc_cc_device(bus_n, VTD_PCI_SLOT(devfn_it), VTD_PCI_FUNC(devfn_it)); vtd_as->context_cache_entry.context_cache_gen = 0; + /* + * So a device is moving out of (or moving into) a + * domain, a replay() suites here to notify all the + * IOMMU_NOTIFIER_MAP registers about this change. + * This won't bring bad even if we have no such + * notifier registered - the IOMMU notification + * framework will skip MAP notifications if that + * happened. + */ + memory_region_iommu_replay_all(&vtd_as->iommu); } } } @@ -1152,12 +1180,53 @@ static void vtd_iotlb_global_invalidate(IntelIOMMUState *s) { trace_vtd_iotlb_reset("global invalidation recved"); vtd_reset_iotlb(s); + vtd_iommu_replay_all(s); } static void vtd_iotlb_domain_invalidate(IntelIOMMUState *s, uint16_t domain_id) { + IntelIOMMUNotifierNode *node; + VTDContextEntry ce; + VTDAddressSpace *vtd_as; + g_hash_table_foreach_remove(s->iotlb, vtd_hash_remove_by_domain, &domain_id); + + QLIST_FOREACH(node, &s->notifiers_list, next) { + vtd_as = node->vtd_as; + if (!vtd_dev_to_context_entry(s, pci_bus_num(vtd_as->bus), + vtd_as->devfn, &ce) && + domain_id == VTD_CONTEXT_ENTRY_DID(ce.hi)) { + memory_region_iommu_replay_all(&vtd_as->iommu); + } + } +} + +static int vtd_page_invalidate_notify_hook(IOMMUTLBEntry *entry, + void *private) +{ + memory_region_notify_iommu((MemoryRegion *)private, *entry); + return 0; +} + +static void vtd_iotlb_page_invalidate_notify(IntelIOMMUState *s, + uint16_t domain_id, hwaddr addr, + uint8_t am) +{ + IntelIOMMUNotifierNode *node; + VTDContextEntry ce; + int ret; + + QLIST_FOREACH(node, &(s->notifiers_list), next) { + VTDAddressSpace *vtd_as = node->vtd_as; + ret = vtd_dev_to_context_entry(s, pci_bus_num(vtd_as->bus), + vtd_as->devfn, &ce); + if (!ret && domain_id == VTD_CONTEXT_ENTRY_DID(ce.hi)) { + vtd_page_walk(&ce, addr, addr + (1 << am) * VTD_PAGE_SIZE, + vtd_page_invalidate_notify_hook, + (void *)&vtd_as->iommu, true); + } + } } static void vtd_iotlb_page_invalidate(IntelIOMMUState *s, uint16_t domain_id, @@ -1170,6 +1239,7 @@ static void vtd_iotlb_page_invalidate(IntelIOMMUState *s, uint16_t domain_id, info.addr = addr; info.mask = ~((1 << am) - 1); g_hash_table_foreach_remove(s->iotlb, vtd_hash_remove_by_page, &info); + vtd_iotlb_page_invalidate_notify(s, domain_id, addr, am); } /* Flush IOTLB @@ -2187,15 +2257,33 @@ static void vtd_iommu_notify_flag_changed(MemoryRegion *iommu, IOMMUNotifierFlag new) { VTDAddressSpace *vtd_as = container_of(iommu, VTDAddressSpace, iommu); + IntelIOMMUState *s = vtd_as->iommu_state; + IntelIOMMUNotifierNode *node = NULL; + IntelIOMMUNotifierNode *next_node = NULL; - if (new & IOMMU_NOTIFIER_MAP) { - error_report("Device at bus %s addr %02x.%d requires iommu " - "notifier which is currently not supported by " - "intel-iommu emulation", - vtd_as->bus->qbus.name, PCI_SLOT(vtd_as->devfn), - PCI_FUNC(vtd_as->devfn)); + if (!s->caching_mode && new & IOMMU_NOTIFIER_MAP) { + error_report("We need to set cache_mode=1 for intel-iommu to enable " + "device assignment with IOMMU protection."); exit(1); } + + if (old == IOMMU_NOTIFIER_NONE) { + node = g_malloc0(sizeof(*node)); + node->vtd_as = vtd_as; + QLIST_INSERT_HEAD(&s->notifiers_list, node, next); + return; + } + + /* update notifier node with new flags */ + QLIST_FOREACH_SAFE(node, &s->notifiers_list, next, next_node) { + if (node->vtd_as == vtd_as) { + if (new == IOMMU_NOTIFIER_NONE) { + QLIST_REMOVE(node, next); + g_free(node); + } + return; + } + } } static const VMStateDescription vtd_vmstate = { @@ -2613,6 +2701,74 @@ VTDAddressSpace *vtd_find_add_as(IntelIOMMUState *s, PCIBus *bus, int devfn) return vtd_dev_as; } +/* Unmap the whole range in the notifier's scope. */ +static void vtd_address_space_unmap(VTDAddressSpace *as, IOMMUNotifier *n) +{ + IOMMUTLBEntry entry; + hwaddr size; + hwaddr start = n->start; + hwaddr end = n->end; + + /* + * Note: all the codes in this function has a assumption that IOVA + * bits are no more than VTD_MGAW bits (which is restricted by + * VT-d spec), otherwise we need to consider overflow of 64 bits. + */ + + if (end > VTD_ADDRESS_SIZE) { + /* + * Don't need to unmap regions that is bigger than the whole + * VT-d supported address space size + */ + end = VTD_ADDRESS_SIZE; + } + + assert(start <= end); + size = end - start; + + if (ctpop64(size) != 1) { + /* + * This size cannot format a correct mask. Let's enlarge it to + * suite the minimum available mask. + */ + int n = 64 - clz64(size); + if (n > VTD_MGAW) { + /* should not happen, but in case it happens, limit it */ + n = VTD_MGAW; + } + size = 1ULL << n; + } + + entry.target_as = &address_space_memory; + /* Adjust iova for the size */ + entry.iova = n->start & ~(size - 1); + /* This field is meaningless for unmap */ + entry.translated_addr = 0; + entry.perm = IOMMU_NONE; + entry.addr_mask = size - 1; + + trace_vtd_as_unmap_whole(pci_bus_num(as->bus), + VTD_PCI_SLOT(as->devfn), + VTD_PCI_FUNC(as->devfn), + entry.iova, size); + + memory_region_notify_one(n, &entry); +} + +static void vtd_address_space_unmap_all(IntelIOMMUState *s) +{ + IntelIOMMUNotifierNode *node; + VTDAddressSpace *vtd_as; + IOMMUNotifier *n; + + QLIST_FOREACH(node, &s->notifiers_list, next) { + vtd_as = node->vtd_as; + IOMMU_NOTIFIER_FOREACH(n, &vtd_as->iommu) { + vtd_address_space_unmap(vtd_as, n); + } + } +} + static int vtd_replay_hook(IOMMUTLBEntry *entry, void *private) { memory_region_notify_one((IOMMUNotifier *)private, entry); @@ -2626,16 +2782,19 @@ static void vtd_iommu_replay(MemoryRegion *mr, IOMMUNotifier *n) uint8_t bus_n = pci_bus_num(vtd_as->bus); VTDContextEntry ce; + /* + * The replay can be triggered by either a invalidation or a newly + * created entry. No matter what, we release existing mappings + * (it means flushing caches for UNMAP-only registers). + */ + vtd_address_space_unmap(vtd_as, n); + if (vtd_dev_to_context_entry(s, bus_n, vtd_as->devfn, &ce) == 0) { - /* - * Scanned a valid context entry, walk over the pages and - * notify when needed. - */ trace_vtd_replay_ce_valid(bus_n, PCI_SLOT(vtd_as->devfn), PCI_FUNC(vtd_as->devfn), VTD_CONTEXT_ENTRY_DID(ce.hi), ce.hi, ce.lo); - vtd_page_walk(&ce, 0, ~0ULL, vtd_replay_hook, (void *)n); + vtd_page_walk(&ce, 0, ~0ULL, vtd_replay_hook, (void *)n, false); } else { trace_vtd_replay_ce_invalid(bus_n, PCI_SLOT(vtd_as->devfn), PCI_FUNC(vtd_as->devfn)); @@ -2754,6 +2913,11 @@ static void vtd_reset(DeviceState *dev) VTD_DPRINTF(GENERAL, ""); vtd_init(s); + + /* + * When device reset, throw away all mappings and external caches + */ + vtd_address_space_unmap_all(s); } static AddressSpace *vtd_host_dma_iommu(PCIBus *bus, void *opaque, int devfn) @@ -2817,6 +2981,7 @@ static void vtd_realize(DeviceState *dev, Error **errp) return; } + QLIST_INIT(&s->notifiers_list); memset(s->vtd_as_by_bus_num, 0, sizeof(s->vtd_as_by_bus_num)); memory_region_init_io(&s->csrmem, OBJECT(s), &vtd_mem_ops, s, "intel_iommu", DMAR_REG_SIZE); diff --git a/hw/i386/intel_iommu_internal.h b/hw/i386/intel_iommu_internal.h index 4104121..29d6707 100644 --- a/hw/i386/intel_iommu_internal.h +++ b/hw/i386/intel_iommu_internal.h @@ -197,6 +197,7 @@ #define VTD_DOMAIN_ID_MASK ((1UL << VTD_DOMAIN_ID_SHIFT) - 1) #define VTD_CAP_ND (((VTD_DOMAIN_ID_SHIFT - 4) / 2) & 7ULL) #define VTD_MGAW 39 /* Maximum Guest Address Width */ +#define VTD_ADDRESS_SIZE (1ULL << VTD_MGAW) #define VTD_CAP_MGAW (((VTD_MGAW - 1) & 0x3fULL) << 16) #define VTD_MAMV 18ULL #define VTD_CAP_MAMV (VTD_MAMV << 48) diff --git a/hw/i386/trace-events b/hw/i386/trace-events index 3c3a167..04a6980 100644 --- a/hw/i386/trace-events +++ b/hw/i386/trace-events @@ -37,6 +37,7 @@ vtd_page_walk_skip_read(uint64_t iova, uint64_t next) "Page walk skip iova 0x%"P vtd_page_walk_skip_perm(uint64_t iova, uint64_t next) "Page walk skip iova 0x%"PRIx64" - 0x%"PRIx64" due to perm empty" vtd_page_walk_skip_reserve(uint64_t iova, uint64_t next) "Page walk skip iova 0x%"PRIx64" - 0x%"PRIx64" due to rsrv set" vtd_switch_address_space(uint8_t bus, uint8_t slot, uint8_t fn, bool on) "Device %02x:%02x.%x switching address space (iommu enabled=%d)" +vtd_as_unmap_whole(uint8_t bus, uint8_t slot, uint8_t fn, uint64_t iova, uint64_t size) "Device %02x:%02x.%x start 0x%"PRIx64" size 0x%"PRIx64 # hw/i386/amd_iommu.c amdvi_evntlog_fail(uint64_t addr, uint32_t head) "error: fail to write at addr 0x%"PRIx64" + offset 0x%"PRIx32 diff --git a/include/hw/i386/intel_iommu.h b/include/hw/i386/intel_iommu.h index 8f212a1..3e51876 100644 --- a/include/hw/i386/intel_iommu.h +++ b/include/hw/i386/intel_iommu.h @@ -63,6 +63,7 @@ typedef union VTD_IR_TableEntry VTD_IR_TableEntry; typedef union VTD_IR_MSIAddress VTD_IR_MSIAddress; typedef struct VTDIrq VTDIrq; typedef struct VTD_MSIMessage VTD_MSIMessage; +typedef struct IntelIOMMUNotifierNode IntelIOMMUNotifierNode; /* Context-Entry */ struct VTDContextEntry { @@ -249,6 +250,11 @@ struct VTD_MSIMessage { /* When IR is enabled, all MSI/MSI-X data bits should be zero */ #define VTD_IR_MSI_DATA (0) +struct IntelIOMMUNotifierNode { + VTDAddressSpace *vtd_as; + QLIST_ENTRY(IntelIOMMUNotifierNode) next; +}; + /* The iommu (DMAR) device state struct */ struct IntelIOMMUState { X86IOMMUState x86_iommu; @@ -286,6 +292,8 @@ struct IntelIOMMUState { MemoryRegionIOMMUOps iommu_ops; GHashTable *vtd_as_by_busptr; /* VTDBus objects indexed by PCIBus* reference */ VTDBus *vtd_as_by_bus_num[VTD_PCI_BUS_MAX]; /* VTDBus objects indexed by bus number */ + /* list of registered notifiers */ + QLIST_HEAD(, IntelIOMMUNotifierNode) notifiers_list; /* interrupt remapping */ bool intr_enabled; /* Whether guest enabled IR */ -- 2.7.4