From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 40A44372EEF; Fri, 10 Jul 2026 06:17:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=13.77.154.182 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783664271; cv=none; b=kYfhcq54WP08TC6lAYOy/gkfD0FDy7me5kd6Zwrzf1iqSsTCgHiRoW1pknbOVWB94pUefRtlOKAv71aDO+c1oBJzfaPyk1b/UdgPT6hDYSknsYvzmYI0Z1pOPc+0Eyl6zlpBguMYuur9lbFkM2lgBdX2eZTYXCqNhSynjpYD6Ow= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783664271; c=relaxed/simple; bh=XOmSjByoNF6Vt4jgC7Oz9VwkAlxisH3g8HUOSqtXj8g=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=eNgWpoIkJrmwoMTPDOjix+Mxjr7TGwl70rzWm18xBJcGaRLgGeJGAch13yra6+3ctpBxZqvWpe96HWPg7rx3K/2JalHG5wqn3iJrmH/jPpcMilMJ0MZwrW191TFWNAERrievGoJyPLZDrHx25TnEP0Z2JepSZ08n+omz6hpJg40= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com; spf=pass smtp.mailfrom=linux.microsoft.com; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b=YNqa0lUn; arc=none smtp.client-ip=13.77.154.182 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b="YNqa0lUn" Received: from localhost (unknown [167.220.233.38]) by linux.microsoft.com (Postfix) with ESMTPSA id 3839B20B716E; Thu, 9 Jul 2026 23:17:42 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 3839B20B716E DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1783664262; bh=5BI1bwekiHhmXFmNYH3osBguDBBQ2ik4qNO2EtDDABM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=YNqa0lUnd+91XFtKhumTUuIQSy5ymXySxSHsDfPqXrA1xNJyuESOexSzLLaDphq7b jyRGPVEgyP4IRfULmaHSeagXGJdN4TWsSjHa1LDg2HxO20SohSYAfhc+akJ+Rgsl3v hqdL5nVm1HB+kjepLHBimGMiY57EwZakHmmpTrc8= Date: Fri, 10 Jul 2026 14:17:46 +0800 From: Yu Zhang To: Michael Kelley Cc: "linux-kernel@vger.kernel.org" , "linux-hyperv@vger.kernel.org" , "iommu@lists.linux.dev" , "linux-pci@vger.kernel.org" , "linux-arch@vger.kernel.org" , "wei.liu@kernel.org" , "kys@microsoft.com" , "haiyangz@microsoft.com" , "decui@microsoft.com" , "longli@microsoft.com" , "joro@8bytes.org" , "will@kernel.org" , "robin.murphy@arm.com" , "bhelgaas@google.com" , "kwilczynski@kernel.org" , "lpieralisi@kernel.org" , "mani@kernel.org" , "robh@kernel.org" , "arnd@arndb.de" , "jgg@ziepe.ca" , "jacob.pan@linux.microsoft.com" , "tgopinath@linux.microsoft.com" , "easwar.hariharan@linux.microsoft.com" , "mrathor@linux.microsoft.com" Subject: Re: [PATCH v2 1/4] hyperv: Introduce new hypercall interfaces used by Hyper-V guest IOMMU Message-ID: References: <20260702160518.311234-1-zhangyu1@linux.microsoft.com> <20260702160518.311234-2-zhangyu1@linux.microsoft.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Thu, Jul 09, 2026 at 07:06:19PM +0000, Michael Kelley wrote: > From: Yu Zhang Sent: Thursday, July 2, 2026 9:05 AM > > > > From: Wei Liu > > > > Hyper-V guest IOMMU is a para-virtualized IOMMU based on hypercalls. > > Introduce the hypercalls used by the child partition to interact with > > this facility. > > > > These hypercalls fall into below categories: > > - Detection and capability: HVCALL_GET_IOMMU_CAPABILITIES is used to > > detect the existence and capabilities of the guest IOMMU. > > > > - Device management: HVCALL_GET_LOGICAL_DEVICE_PROPERTY is used to > > check whether an endpoint device is managed by the guest IOMMU. > > > > - Domain management: A set of hypercalls is provided to handle the > > creation, configuration, and deletion of guest domains, as well as > > the attachment/detachment of endpoint devices to/from those domains. > > > > - IOTLB flushing: HVCALL_FLUSH_DEVICE_DOMAIN is used to ask Hyper-V > > for a domain-selective IOTLB flush (which in its handler may flush > > the device TLB as well). > > > > Signed-off-by: Wei Liu > > Co-developed-by: Easwar Hariharan > > Signed-off-by: Easwar Hariharan > > Co-developed-by: Yu Zhang > > Signed-off-by: Yu Zhang > > --- > > include/hyperv/hvgdk_mini.h | 8 +++ > > include/hyperv/hvhdk_mini.h | 124 ++++++++++++++++++++++++++++++++++++ > > 2 files changed, 132 insertions(+) > > > > diff --git a/include/hyperv/hvgdk_mini.h b/include/hyperv/hvgdk_mini.h > > index 6a4e8b9d570f..5bdbb44da112 100644 > > --- a/include/hyperv/hvgdk_mini.h > > +++ b/include/hyperv/hvgdk_mini.h > > @@ -486,10 +486,16 @@ union hv_vp_assist_msr_contents { /* > > HV_REGISTER_VP_ASSIST_PAGE */ > > #define HVCALL_GET_VP_INDEX_FROM_APIC_ID 0x009a > > #define HVCALL_FLUSH_GUEST_PHYSICAL_ADDRESS_SPACE 0x00af > > #define HVCALL_FLUSH_GUEST_PHYSICAL_ADDRESS_LIST 0x00b0 > > +#define HVCALL_CREATE_DEVICE_DOMAIN 0x00b1 > > +#define HVCALL_ATTACH_DEVICE_DOMAIN 0x00b2 > > #define HVCALL_SIGNAL_EVENT_DIRECT 0x00c0 > > #define HVCALL_POST_MESSAGE_DIRECT 0x00c1 > > #define HVCALL_DISPATCH_VP 0x00c2 > > +#define HVCALL_DETACH_DEVICE_DOMAIN 0x00c4 > > +#define HVCALL_DELETE_DEVICE_DOMAIN 0x00c5 > > #define HVCALL_GET_GPA_PAGES_ACCESS_STATES 0x00c9 > > +#define HVCALL_CONFIGURE_DEVICE_DOMAIN 0x00ce > > +#define HVCALL_FLUSH_DEVICE_DOMAIN 0x00d0 > > #define HVCALL_ACQUIRE_SPARSE_SPA_PAGE_HOST_ACCESS 0x00d7 > > #define HVCALL_RELEASE_SPARSE_SPA_PAGE_HOST_ACCESS 0x00d8 > > #define HVCALL_MODIFY_SPARSE_GPA_PAGE_HOST_VISIBILITY 0x00db > > @@ -502,6 +508,8 @@ union hv_vp_assist_msr_contents { /* > > HV_REGISTER_VP_ASSIST_PAGE */ > > #define HVCALL_MMIO_READ 0x0106 > > #define HVCALL_MMIO_WRITE 0x0107 > > #define HVCALL_DISABLE_HYP_EX 0x010f > > +#define HVCALL_GET_IOMMU_CAPABILITIES 0x0125 > > +#define HVCALL_GET_LOGICAL_DEVICE_PROPERTY 0x0127 > > #define HVCALL_MAP_STATS_PAGE2 0x0131 > > > > /* HV_HYPERCALL_INPUT */ > > diff --git a/include/hyperv/hvhdk_mini.h b/include/hyperv/hvhdk_mini.h > > index b4cb2fa26e9b..493608e791b4 100644 > > --- a/include/hyperv/hvhdk_mini.h > > +++ b/include/hyperv/hvhdk_mini.h > > @@ -547,4 +547,128 @@ union hv_device_id { /* HV_DEVICE_ID */ > > } acpi; > > } __packed; > > > > +/* Device domain types */ > > +#define HV_DEVICE_DOMAIN_TYPE_S1 1 /* Stage 1 domain */ > > + > > +/* ID for default domain and NULL domain */ > > +#define HV_DEVICE_DOMAIN_ID_DEFAULT 0 > > +#define HV_DEVICE_DOMAIN_ID_NULL 0xFFFFFFFFULL > > + > > +union hv_device_domain_id { > > + u64 as_uint64; > > + struct { > > + u32 type: 4; > > + u32 reserved: 28; > > + u32 id; > > + } __packed; > > +}; > > + > > +struct hv_input_device_domain { > > + u64 partition_id; > > + union hv_input_vtl owner_vtl; > > + u8 padding[7]; > > + union hv_device_domain_id domain_id; > > +} __packed; > > + > > +union hv_create_device_domain_flags { > > + u32 as_uint32; > > + struct { > > + u32 forward_progress_required: 1; > > + u32 inherit_owning_vtl: 1; > > + u32 reserved: 30; > > + } __packed; > > +}; > > + > > +struct hv_input_create_device_domain { > > + struct hv_input_device_domain device_domain; > > + union hv_create_device_domain_flags create_device_domain_flags; > > +} __packed; > > + > > +struct hv_input_delete_device_domain { > > + struct hv_input_device_domain device_domain; > > +} __packed; > > + > > +struct hv_input_attach_device_domain { > > + struct hv_input_device_domain device_domain; > > + union hv_device_id device_id; > > +} __packed; > > + > > +struct hv_input_detach_device_domain { > > + u64 partition_id; > > + union hv_device_id device_id; > > +} __packed; > > + > > +struct hv_device_domain_settings { > > + struct { > > + /* > > + * Enable translations. If not enabled, all transaction bypass > > + * S1 translations. > > + */ > > + u64 translation_enabled: 1; > > + u64 blocked: 1; > > + /* > > + * First stage address translation paging mode: > > + * 0: 4-level paging (default) > > + * 1: 5-level paging > > + */ > > + u64 first_stage_paging_mode: 1; > > + u64 reserved: 61; > > + } flags; > > + > > + /* Address of translation table */ > > + u64 page_table_root; > > +} __packed; > > + > > +struct hv_input_configure_device_domain { > > + struct hv_input_device_domain device_domain; > > + struct hv_device_domain_settings settings; > > +} __packed; > > + > > +struct hv_input_get_iommu_capabilities { > > + u64 partition_id; > > + u64 reserved; > > +} __packed; > > + > > +struct hv_output_get_iommu_capabilities { > > + u32 size; > > + u16 reserved; > > + u8 max_iova_width; > > + u8 max_pasid_width; > > + > > +#define HV_IOMMU_CAP_PRESENT (1ULL << 0) > > +#define HV_IOMMU_CAP_S2 (1ULL << 1) > > +#define HV_IOMMU_CAP_S1 (1ULL << 2) > > +#define HV_IOMMU_CAP_S1_5LVL (1ULL << 3) > > +#define HV_IOMMU_CAP_PASID (1ULL << 4) > > +#define HV_IOMMU_CAP_ATS (1ULL << 5) > > +#define HV_IOMMU_CAP_PRI (1ULL << 6) > > hvgdk_mini.h mostly uses the Linux BIT() and BIT_ULL() > macros instead of explicit shifts. But this is hvhdk_mini.h. > Does it need to play by a different set of rules for > compatibility with the original Windows files? I think > the Linux BIT* macros are preferable if possible. > I'm not aware of any compatibility requirement. And since it does not change the real definition, I guess we should use BIT*. > > + > > + u64 iommu_cap; > > + u64 pgsize_bitmap; > > +} __packed; > > + > > +enum hv_logical_device_property_code { > > + HV_LOGICAL_DEVICE_PROPERTY_PVIOMMU = 10, > > +}; > > + > > +struct hv_input_get_logical_device_property { > > + u64 partition_id; > > + u64 logical_device_id; > > + /* Takes values from enum hv_logical_device_property_code. */ > > + u32 code; > > + u32 reserved; > > +} __packed; > > + > > +struct hv_output_get_logical_device_property { > > +#define HV_DEVICE_IOMMU_ENABLED (1ULL << 0) > > Same here about BIT_ULL(). > Will fix. Thanks! B.R. Yu > > + u64 device_iommu; > > + u64 reserved; > > +} __packed; > > + > > +struct hv_input_flush_device_domain { > > + struct hv_input_device_domain device_domain; > > + u32 flags; > > + u32 reserved; > > +} __packed; > > + > > #endif /* _HV_HVHDK_MINI_H */ > > -- > > 2.52.0 > > >