From nobody Sat Feb 7 15:15:18 2026 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 3D53F36D518; Tue, 20 Jan 2026 06:43:30 +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=1768891419; cv=none; b=gbqAay4NBERbaaGx6FJLHAPBQPjkMhhaXyJt8Kpupr48NkrVMUnQ4LSzJLsz1KjSdl8HLrGlGvdXVHku4FMAkf/lZH0nqnpCDUBYAIKX7fAwhNmCVVsY1Lfzd2rgFZk81oySS8dWOqQNFYjRJkq7UyV4L0pPrnEKyuLT8Ff0Xns= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768891419; c=relaxed/simple; bh=ngFAuJnfcfXBr4kJX71bsAIldIKd7TgtHjND03nfXww=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=MDhghRBkU9u4ugzuAtGbMJliQtJVjlz8uTzFWPX3NurK5dsLVYQJdLO9dku7P8BhuDOwUAOVttW8N+IS9sNNwHFoyT5Bmt/G9Kjn7SWDtKZfWY3LWUyq7pc3NoEbPUnE26sDjnTJGnIPJs+yGXGt+0HW73nFqMtltPYfUaRP1yg= 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=HGdtXVc2; 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="HGdtXVc2" Received: from mrdev.corp.microsoft.com (192-184-212-33.fiber.dynamic.sonic.net [192.184.212.33]) by linux.microsoft.com (Postfix) with ESMTPSA id 3BA9720B716A; Mon, 19 Jan 2026 22:43:27 -0800 (PST) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 3BA9720B716A DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1768891408; bh=m45lmngnneFEFrRyGJR4mUwoMKqxtY0RUEN+/lvw4/4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=HGdtXVc2BXgm92n5ocikgwapcrs0HLEgrr6+dxRy3TgP+wqnISmLINE6igxoPsAeS 8r68DlGdoTXyTpQ6RkFDSB8egv/wuwQ58Vk4Hwoa5+iO6ykl7h6FsRiDhqXdYbN7qB ejPq68EVm2n6fmepTibXWl9+2yJi+M/QsFhPfD/Q= From: Mukesh R To: linux-kernel@vger.kernel.org, linux-hyperv@vger.kernel.org, linux-arm-kernel@lists.infradead.org, iommu@lists.linux.dev, linux-pci@vger.kernel.org, linux-arch@vger.kernel.org Cc: kys@microsoft.com, haiyangz@microsoft.com, wei.liu@kernel.org, decui@microsoft.com, longli@microsoft.com, catalin.marinas@arm.com, will@kernel.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com, joro@8bytes.org, lpieralisi@kernel.org, kwilczynski@kernel.org, mani@kernel.org, robh@kernel.org, bhelgaas@google.com, arnd@arndb.de, nunodasneves@linux.microsoft.com, mhklinux@outlook.com, romank@linux.microsoft.com Subject: [PATCH v0 01/15] iommu/hyperv: rename hyperv-iommu.c to hyperv-irq.c Date: Mon, 19 Jan 2026 22:42:16 -0800 Message-ID: <20260120064230.3602565-2-mrathor@linux.microsoft.com> X-Mailer: git-send-email 2.51.2.vfs.0.1 In-Reply-To: <20260120064230.3602565-1-mrathor@linux.microsoft.com> References: <20260120064230.3602565-1-mrathor@linux.microsoft.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Mukesh Rathor This file actually implements irq remapping, so rename to more appropriate hyperv-irq.c. A new file named hyperv-iommu.c will be introduced later. Also, move CONFIG_IRQ_REMAP out of the file and add to Makefile. Signed-off-by: Mukesh Rathor Reviewed-by: Anirudh Rayabharam (Microsoft) --- MAINTAINERS | 2 +- drivers/iommu/Kconfig | 1 + drivers/iommu/Makefile | 2 +- drivers/iommu/{hyperv-iommu.c =3D> hyperv-irq.c} | 4 ---- 4 files changed, 3 insertions(+), 6 deletions(-) rename drivers/iommu/{hyperv-iommu.c =3D> hyperv-irq.c} (99%) diff --git a/MAINTAINERS b/MAINTAINERS index 5b11839cba9d..381a0e086382 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -11741,7 +11741,7 @@ F: drivers/hid/hid-hyperv.c F: drivers/hv/ F: drivers/infiniband/hw/mana/ F: drivers/input/serio/hyperv-keyboard.c -F: drivers/iommu/hyperv-iommu.c +F: drivers/iommu/hyperv-irq.c F: drivers/net/ethernet/microsoft/ F: drivers/net/hyperv/ F: drivers/pci/controller/pci-hyperv-intf.c diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig index 99095645134f..b4cc2b42b338 100644 --- a/drivers/iommu/Kconfig +++ b/drivers/iommu/Kconfig @@ -355,6 +355,7 @@ config HYPERV_IOMMU bool "Hyper-V IRQ Handling" depends on HYPERV && X86 select IOMMU_API + select IRQ_REMAP default HYPERV help Stub IOMMU driver to handle IRQs to support Hyper-V Linux diff --git a/drivers/iommu/Makefile b/drivers/iommu/Makefile index 8e8843316c4b..598c39558e7d 100644 --- a/drivers/iommu/Makefile +++ b/drivers/iommu/Makefile @@ -30,7 +30,7 @@ obj-$(CONFIG_TEGRA_IOMMU_SMMU) +=3D tegra-smmu.o obj-$(CONFIG_EXYNOS_IOMMU) +=3D exynos-iommu.o obj-$(CONFIG_FSL_PAMU) +=3D fsl_pamu.o fsl_pamu_domain.o obj-$(CONFIG_S390_IOMMU) +=3D s390-iommu.o -obj-$(CONFIG_HYPERV_IOMMU) +=3D hyperv-iommu.o +obj-$(CONFIG_HYPERV_IOMMU) +=3D hyperv-irq.o obj-$(CONFIG_VIRTIO_IOMMU) +=3D virtio-iommu.o obj-$(CONFIG_IOMMU_SVA) +=3D iommu-sva.o obj-$(CONFIG_IOMMU_IOPF) +=3D io-pgfault.o diff --git a/drivers/iommu/hyperv-iommu.c b/drivers/iommu/hyperv-irq.c similarity index 99% rename from drivers/iommu/hyperv-iommu.c rename to drivers/iommu/hyperv-irq.c index 0961ac805944..1944440a5004 100644 --- a/drivers/iommu/hyperv-iommu.c +++ b/drivers/iommu/hyperv-irq.c @@ -24,8 +24,6 @@ =20 #include "irq_remapping.h" =20 -#ifdef CONFIG_IRQ_REMAP - /* * According 82093AA IO-APIC spec , IO APIC has a 24-entry Interrupt * Redirection Table. Hyper-V exposes one single IO-APIC and so define @@ -330,5 +328,3 @@ static const struct irq_domain_ops hyperv_root_ir_domai= n_ops =3D { .alloc =3D hyperv_root_irq_remapping_alloc, .free =3D hyperv_root_irq_remapping_free, }; - -#endif --=20 2.51.2.vfs.0.1 From nobody Sat Feb 7 15:15:18 2026 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id AAFC038B7AB; Tue, 20 Jan 2026 06:43:32 +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=1768891424; cv=none; b=eA4LjKFfqKMXO2B7y2TEYNyIwfPOE67xf6DuwszWZFfR9B/5zhiRUSg03rAA4z0E7bxfxbAQpYnnzgP7IXSnygZbnHGc07b5MIKI5pFJi5ezvvxCMuugZoPIHlbNLwZlDVJlZDltHdOThIJBGz67i39wiFGiqudAq8+hLkFDWOM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768891424; c=relaxed/simple; bh=c6JvVOx8H/VsONhvif1DwT/sjYWxXqar3Z23TKRFpvU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=SYeoYva0nicARcHWe8jNdxbinACMhDlAOD5L0jpYvptQsj3EFDa558xAU7wN6xF2XewBEl1Cyg51MwEUf9+3gPjlWOFatvx+FFDXwv+zSwlOWAvALa3gyGikR9K95LW4PlutY9mPiIbR3Q8Qkwm+RI+bgSv8MzXgSUi5Y+n+Yj0= 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=CtOkBlKD; 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="CtOkBlKD" Received: from mrdev.corp.microsoft.com (192-184-212-33.fiber.dynamic.sonic.net [192.184.212.33]) by linux.microsoft.com (Postfix) with ESMTPSA id 61BB720B716B; Mon, 19 Jan 2026 22:43:28 -0800 (PST) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 61BB720B716B DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1768891409; bh=OW5YDvS1bnMpcoEg7TkbfyRItoXlmLCY/FzGfytcf20=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=CtOkBlKD1snMCZLTU1RVXK4B70q0j/qdQdNToYjpfbrUk5q1CMAueGuNXVUUUNYGV vyMLMpKqhA268xEuKMPv3jQvKewk211zA7VcqqqSDtn3PgISO8wPVMmPgV+GMAEjlu 0irIps+DTXZb3EICOgazglMYdg3TZSs3+MuikP7M= From: Mukesh R To: linux-kernel@vger.kernel.org, linux-hyperv@vger.kernel.org, linux-arm-kernel@lists.infradead.org, iommu@lists.linux.dev, linux-pci@vger.kernel.org, linux-arch@vger.kernel.org Cc: kys@microsoft.com, haiyangz@microsoft.com, wei.liu@kernel.org, decui@microsoft.com, longli@microsoft.com, catalin.marinas@arm.com, will@kernel.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com, joro@8bytes.org, lpieralisi@kernel.org, kwilczynski@kernel.org, mani@kernel.org, robh@kernel.org, bhelgaas@google.com, arnd@arndb.de, nunodasneves@linux.microsoft.com, mhklinux@outlook.com, romank@linux.microsoft.com Subject: [PATCH v0 02/15] x86/hyperv: cosmetic changes in irqdomain.c for readability Date: Mon, 19 Jan 2026 22:42:17 -0800 Message-ID: <20260120064230.3602565-3-mrathor@linux.microsoft.com> X-Mailer: git-send-email 2.51.2.vfs.0.1 In-Reply-To: <20260120064230.3602565-1-mrathor@linux.microsoft.com> References: <20260120064230.3602565-1-mrathor@linux.microsoft.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Mukesh Rathor Make cosmetic changes: o Rename struct pci_dev *dev to *pdev since there are cases of struct device *dev in the file and all over the kernel o Rename hv_build_pci_dev_id to hv_build_devid_type_pci in anticipation of building different types of device ids o Fix checkpatch.pl issues with return and extraneous printk o Replace spaces with tabs o Rename struct hv_devid *xxx to struct hv_devid *hv_devid given code paths involve many types of device ids o Fix indentation in a large if block by using goto. There are no functional changes. Signed-off-by: Mukesh Rathor Reviewed-by: Anirudh Rayabharam (Microsoft) --- arch/x86/hyperv/irqdomain.c | 197 +++++++++++++++++++----------------- 1 file changed, 103 insertions(+), 94 deletions(-) diff --git a/arch/x86/hyperv/irqdomain.c b/arch/x86/hyperv/irqdomain.c index c3ba12b1bc07..f6b61483b3b8 100644 --- a/arch/x86/hyperv/irqdomain.c +++ b/arch/x86/hyperv/irqdomain.c @@ -1,5 +1,4 @@ // SPDX-License-Identifier: GPL-2.0 - /* * Irqdomain for Linux to run as the root partition on Microsoft Hyperviso= r. * @@ -14,8 +13,8 @@ #include #include =20 -static int hv_map_interrupt(union hv_device_id device_id, bool level, - int cpu, int vector, struct hv_interrupt_entry *entry) +static int hv_map_interrupt(union hv_device_id hv_devid, bool level, + int cpu, int vector, struct hv_interrupt_entry *ret_entry) { struct hv_input_map_device_interrupt *input; struct hv_output_map_device_interrupt *output; @@ -32,7 +31,7 @@ static int hv_map_interrupt(union hv_device_id device_id,= bool level, intr_desc =3D &input->interrupt_descriptor; memset(input, 0, sizeof(*input)); input->partition_id =3D hv_current_partition_id; - input->device_id =3D device_id.as_uint64; + input->device_id =3D hv_devid.as_uint64; intr_desc->interrupt_type =3D HV_X64_INTERRUPT_TYPE_FIXED; intr_desc->vector_count =3D 1; intr_desc->target.vector =3D vector; @@ -44,7 +43,7 @@ static int hv_map_interrupt(union hv_device_id device_id,= bool level, =20 intr_desc->target.vp_set.valid_bank_mask =3D 0; intr_desc->target.vp_set.format =3D HV_GENERIC_SET_SPARSE_4K; - nr_bank =3D cpumask_to_vpset(&(intr_desc->target.vp_set), cpumask_of(cpu)= ); + nr_bank =3D cpumask_to_vpset(&intr_desc->target.vp_set, cpumask_of(cpu)); if (nr_bank < 0) { local_irq_restore(flags); pr_err("%s: unable to generate VP set\n", __func__); @@ -61,7 +60,7 @@ static int hv_map_interrupt(union hv_device_id device_id,= bool level, =20 status =3D hv_do_rep_hypercall(HVCALL_MAP_DEVICE_INTERRUPT, 0, var_size, input, output); - *entry =3D output->interrupt_entry; + *ret_entry =3D output->interrupt_entry; =20 local_irq_restore(flags); =20 @@ -71,21 +70,19 @@ static int hv_map_interrupt(union hv_device_id device_i= d, bool level, return hv_result_to_errno(status); } =20 -static int hv_unmap_interrupt(u64 id, struct hv_interrupt_entry *old_entry) +static int hv_unmap_interrupt(u64 id, struct hv_interrupt_entry *irq_entry) { unsigned long flags; struct hv_input_unmap_device_interrupt *input; - struct hv_interrupt_entry *intr_entry; u64 status; =20 local_irq_save(flags); input =3D *this_cpu_ptr(hyperv_pcpu_input_arg); =20 memset(input, 0, sizeof(*input)); - intr_entry =3D &input->interrupt_entry; input->partition_id =3D hv_current_partition_id; input->device_id =3D id; - *intr_entry =3D *old_entry; + input->interrupt_entry =3D *irq_entry; =20 status =3D hv_do_hypercall(HVCALL_UNMAP_DEVICE_INTERRUPT, input, NULL); local_irq_restore(flags); @@ -115,67 +112,71 @@ static int get_rid_cb(struct pci_dev *pdev, u16 alias= , void *data) return 0; } =20 -static union hv_device_id hv_build_pci_dev_id(struct pci_dev *dev) +static union hv_device_id hv_build_devid_type_pci(struct pci_dev *pdev) { - union hv_device_id dev_id; + int pos; + union hv_device_id hv_devid; struct rid_data data =3D { .bridge =3D NULL, - .rid =3D PCI_DEVID(dev->bus->number, dev->devfn) + .rid =3D PCI_DEVID(pdev->bus->number, pdev->devfn) }; =20 - pci_for_each_dma_alias(dev, get_rid_cb, &data); + pci_for_each_dma_alias(pdev, get_rid_cb, &data); =20 - dev_id.as_uint64 =3D 0; - dev_id.device_type =3D HV_DEVICE_TYPE_PCI; - dev_id.pci.segment =3D pci_domain_nr(dev->bus); + hv_devid.as_uint64 =3D 0; + hv_devid.device_type =3D HV_DEVICE_TYPE_PCI; + hv_devid.pci.segment =3D pci_domain_nr(pdev->bus); =20 - dev_id.pci.bdf.bus =3D PCI_BUS_NUM(data.rid); - dev_id.pci.bdf.device =3D PCI_SLOT(data.rid); - dev_id.pci.bdf.function =3D PCI_FUNC(data.rid); - dev_id.pci.source_shadow =3D HV_SOURCE_SHADOW_NONE; + hv_devid.pci.bdf.bus =3D PCI_BUS_NUM(data.rid); + hv_devid.pci.bdf.device =3D PCI_SLOT(data.rid); + hv_devid.pci.bdf.function =3D PCI_FUNC(data.rid); + hv_devid.pci.source_shadow =3D HV_SOURCE_SHADOW_NONE; =20 - if (data.bridge) { - int pos; + if (data.bridge =3D=3D NULL) + goto out; =20 - /* - * Microsoft Hypervisor requires a bus range when the bridge is - * running in PCI-X mode. - * - * To distinguish conventional vs PCI-X bridge, we can check - * the bridge's PCI-X Secondary Status Register, Secondary Bus - * Mode and Frequency bits. See PCI Express to PCI/PCI-X Bridge - * Specification Revision 1.0 5.2.2.1.3. - * - * Value zero means it is in conventional mode, otherwise it is - * in PCI-X mode. - */ + /* + * Microsoft Hypervisor requires a bus range when the bridge is + * running in PCI-X mode. + * + * To distinguish conventional vs PCI-X bridge, we can check + * the bridge's PCI-X Secondary Status Register, Secondary Bus + * Mode and Frequency bits. See PCI Express to PCI/PCI-X Bridge + * Specification Revision 1.0 5.2.2.1.3. + * + * Value zero means it is in conventional mode, otherwise it is + * in PCI-X mode. + */ =20 - pos =3D pci_find_capability(data.bridge, PCI_CAP_ID_PCIX); - if (pos) { - u16 status; + pos =3D pci_find_capability(data.bridge, PCI_CAP_ID_PCIX); + if (pos) { + u16 status; =20 - pci_read_config_word(data.bridge, pos + - PCI_X_BRIDGE_SSTATUS, &status); + pci_read_config_word(data.bridge, pos + PCI_X_BRIDGE_SSTATUS, + &status); =20 - if (status & PCI_X_SSTATUS_FREQ) { - /* Non-zero, PCI-X mode */ - u8 sec_bus, sub_bus; + if (status & PCI_X_SSTATUS_FREQ) { + /* Non-zero, PCI-X mode */ + u8 sec_bus, sub_bus; =20 - dev_id.pci.source_shadow =3D HV_SOURCE_SHADOW_BRIDGE_BUS_RANGE; + hv_devid.pci.source_shadow =3D + HV_SOURCE_SHADOW_BRIDGE_BUS_RANGE; =20 - pci_read_config_byte(data.bridge, PCI_SECONDARY_BUS, &sec_bus); - dev_id.pci.shadow_bus_range.secondary_bus =3D sec_bus; - pci_read_config_byte(data.bridge, PCI_SUBORDINATE_BUS, &sub_bus); - dev_id.pci.shadow_bus_range.subordinate_bus =3D sub_bus; - } + pci_read_config_byte(data.bridge, PCI_SECONDARY_BUS, + &sec_bus); + hv_devid.pci.shadow_bus_range.secondary_bus =3D sec_bus; + pci_read_config_byte(data.bridge, PCI_SUBORDINATE_BUS, + &sub_bus); + hv_devid.pci.shadow_bus_range.subordinate_bus =3D sub_bus; } } =20 - return dev_id; +out: + return hv_devid; } =20 -/** - * hv_map_msi_interrupt() - "Map" the MSI IRQ in the hypervisor. +/* + * hv_map_msi_interrupt() - Map the MSI IRQ in the hypervisor. * @data: Describes the IRQ * @out_entry: Hypervisor (MSI) interrupt entry (can be NULL) * @@ -188,22 +189,23 @@ int hv_map_msi_interrupt(struct irq_data *data, { struct irq_cfg *cfg =3D irqd_cfg(data); struct hv_interrupt_entry dummy; - union hv_device_id device_id; + union hv_device_id hv_devid; struct msi_desc *msidesc; - struct pci_dev *dev; + struct pci_dev *pdev; int cpu; =20 msidesc =3D irq_data_get_msi_desc(data); - dev =3D msi_desc_to_pci_dev(msidesc); - device_id =3D hv_build_pci_dev_id(dev); + pdev =3D msi_desc_to_pci_dev(msidesc); + hv_devid =3D hv_build_devid_type_pci(pdev); cpu =3D cpumask_first(irq_data_get_effective_affinity_mask(data)); =20 - return hv_map_interrupt(device_id, false, cpu, cfg->vector, + return hv_map_interrupt(hv_devid, false, cpu, cfg->vector, out_entry ? out_entry : &dummy); } EXPORT_SYMBOL_GPL(hv_map_msi_interrupt); =20 -static inline void entry_to_msi_msg(struct hv_interrupt_entry *entry, stru= ct msi_msg *msg) +static void entry_to_msi_msg(struct hv_interrupt_entry *entry, + struct msi_msg *msg) { /* High address is always 0 */ msg->address_hi =3D 0; @@ -211,17 +213,19 @@ static inline void entry_to_msi_msg(struct hv_interru= pt_entry *entry, struct msi msg->data =3D entry->msi_entry.data.as_uint32; } =20 -static int hv_unmap_msi_interrupt(struct pci_dev *dev, struct hv_interrupt= _entry *old_entry); +static int hv_unmap_msi_interrupt(struct pci_dev *pdev, + struct hv_interrupt_entry *irq_entry); + static void hv_irq_compose_msi_msg(struct irq_data *data, struct msi_msg *= msg) { struct hv_interrupt_entry *stored_entry; struct irq_cfg *cfg =3D irqd_cfg(data); struct msi_desc *msidesc; - struct pci_dev *dev; + struct pci_dev *pdev; int ret; =20 msidesc =3D irq_data_get_msi_desc(data); - dev =3D msi_desc_to_pci_dev(msidesc); + pdev =3D msi_desc_to_pci_dev(msidesc); =20 if (!cfg) { pr_debug("%s: cfg is NULL", __func__); @@ -240,7 +244,7 @@ static void hv_irq_compose_msi_msg(struct irq_data *dat= a, struct msi_msg *msg) stored_entry =3D data->chip_data; data->chip_data =3D NULL; =20 - ret =3D hv_unmap_msi_interrupt(dev, stored_entry); + ret =3D hv_unmap_msi_interrupt(pdev, stored_entry); =20 kfree(stored_entry); =20 @@ -249,10 +253,8 @@ static void hv_irq_compose_msi_msg(struct irq_data *da= ta, struct msi_msg *msg) } =20 stored_entry =3D kzalloc(sizeof(*stored_entry), GFP_ATOMIC); - if (!stored_entry) { - pr_debug("%s: failed to allocate chip data\n", __func__); + if (!stored_entry) return; - } =20 ret =3D hv_map_msi_interrupt(data, stored_entry); if (ret) { @@ -262,18 +264,21 @@ static void hv_irq_compose_msi_msg(struct irq_data *d= ata, struct msi_msg *msg) =20 data->chip_data =3D stored_entry; entry_to_msi_msg(data->chip_data, msg); - - return; } =20 -static int hv_unmap_msi_interrupt(struct pci_dev *dev, struct hv_interrupt= _entry *old_entry) +static int hv_unmap_msi_interrupt(struct pci_dev *pdev, + struct hv_interrupt_entry *irq_entry) { - return hv_unmap_interrupt(hv_build_pci_dev_id(dev).as_uint64, old_entry); + union hv_device_id hv_devid; + + hv_devid =3D hv_build_devid_type_pci(pdev); + return hv_unmap_interrupt(hv_devid.as_uint64, irq_entry); } =20 -static void hv_teardown_msi_irq(struct pci_dev *dev, struct irq_data *irqd) +/* NB: during map, hv_interrupt_entry is saved via data->chip_data */ +static void hv_teardown_msi_irq(struct pci_dev *pdev, struct irq_data *irq= d) { - struct hv_interrupt_entry old_entry; + struct hv_interrupt_entry irq_entry; struct msi_msg msg; =20 if (!irqd->chip_data) { @@ -281,13 +286,13 @@ static void hv_teardown_msi_irq(struct pci_dev *dev, = struct irq_data *irqd) return; } =20 - old_entry =3D *(struct hv_interrupt_entry *)irqd->chip_data; - entry_to_msi_msg(&old_entry, &msg); + irq_entry =3D *(struct hv_interrupt_entry *)irqd->chip_data; + entry_to_msi_msg(&irq_entry, &msg); =20 kfree(irqd->chip_data); irqd->chip_data =3D NULL; =20 - (void)hv_unmap_msi_interrupt(dev, &old_entry); + (void)hv_unmap_msi_interrupt(pdev, &irq_entry); } =20 /* @@ -302,7 +307,8 @@ static struct irq_chip hv_pci_msi_controller =3D { }; =20 static bool hv_init_dev_msi_info(struct device *dev, struct irq_domain *do= main, - struct irq_domain *real_parent, struct msi_domain_info *info) + struct irq_domain *real_parent, + struct msi_domain_info *info) { struct irq_chip *chip =3D info->chip; =20 @@ -317,7 +323,8 @@ static bool hv_init_dev_msi_info(struct device *dev, st= ruct irq_domain *domain, } =20 #define HV_MSI_FLAGS_SUPPORTED (MSI_GENERIC_FLAGS_MASK | MSI_FLAG_PCI_MSIX) -#define HV_MSI_FLAGS_REQUIRED (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF= _CHIP_OPS) +#define HV_MSI_FLAGS_REQUIRED (MSI_FLAG_USE_DEF_DOM_OPS | \ + MSI_FLAG_USE_DEF_CHIP_OPS) =20 static struct msi_parent_ops hv_msi_parent_ops =3D { .supported_flags =3D HV_MSI_FLAGS_SUPPORTED, @@ -329,14 +336,13 @@ static struct msi_parent_ops hv_msi_parent_ops =3D { .init_dev_msi_info =3D hv_init_dev_msi_info, }; =20 -static int hv_msi_domain_alloc(struct irq_domain *d, unsigned int virq, un= signed int nr_irqs, - void *arg) +static int hv_msi_domain_alloc(struct irq_domain *d, unsigned int virq, + unsigned int nr_irqs, void *arg) { /* - * TODO: The allocation bits of hv_irq_compose_msi_msg(), i.e. everything= except - * entry_to_msi_msg() should be in here. + * TODO: The allocation bits of hv_irq_compose_msi_msg(), i.e. + * everything except entry_to_msi_msg() should be in here. */ - int ret; =20 ret =3D irq_domain_alloc_irqs_parent(d, virq, nr_irqs, arg); @@ -344,13 +350,15 @@ static int hv_msi_domain_alloc(struct irq_domain *d, = unsigned int virq, unsigned return ret; =20 for (int i =3D 0; i < nr_irqs; ++i) { - irq_domain_set_info(d, virq + i, 0, &hv_pci_msi_controller, NULL, - handle_edge_irq, NULL, "edge"); + irq_domain_set_info(d, virq + i, 0, &hv_pci_msi_controller, + NULL, handle_edge_irq, NULL, "edge"); } + return 0; } =20 -static void hv_msi_domain_free(struct irq_domain *d, unsigned int virq, un= signed int nr_irqs) +static void hv_msi_domain_free(struct irq_domain *d, unsigned int virq, + unsigned int nr_irqs) { for (int i =3D 0; i < nr_irqs; ++i) { struct irq_data *irqd =3D irq_domain_get_irq_data(d, virq); @@ -362,6 +370,7 @@ static void hv_msi_domain_free(struct irq_domain *d, un= signed int virq, unsigned =20 hv_teardown_msi_irq(to_pci_dev(desc->dev), irqd); } + irq_domain_free_irqs_top(d, virq, nr_irqs); } =20 @@ -394,25 +403,25 @@ struct irq_domain * __init hv_create_pci_msi_domain(v= oid) =20 int hv_unmap_ioapic_interrupt(int ioapic_id, struct hv_interrupt_entry *en= try) { - union hv_device_id device_id; + union hv_device_id hv_devid; =20 - device_id.as_uint64 =3D 0; - device_id.device_type =3D HV_DEVICE_TYPE_IOAPIC; - device_id.ioapic.ioapic_id =3D (u8)ioapic_id; + hv_devid.as_uint64 =3D 0; + hv_devid.device_type =3D HV_DEVICE_TYPE_IOAPIC; + hv_devid.ioapic.ioapic_id =3D (u8)ioapic_id; =20 - return hv_unmap_interrupt(device_id.as_uint64, entry); + return hv_unmap_interrupt(hv_devid.as_uint64, entry); } EXPORT_SYMBOL_GPL(hv_unmap_ioapic_interrupt); =20 int hv_map_ioapic_interrupt(int ioapic_id, bool level, int cpu, int vector, struct hv_interrupt_entry *entry) { - union hv_device_id device_id; + union hv_device_id hv_devid; =20 - device_id.as_uint64 =3D 0; - device_id.device_type =3D HV_DEVICE_TYPE_IOAPIC; - device_id.ioapic.ioapic_id =3D (u8)ioapic_id; + hv_devid.as_uint64 =3D 0; + hv_devid.device_type =3D HV_DEVICE_TYPE_IOAPIC; + hv_devid.ioapic.ioapic_id =3D (u8)ioapic_id; =20 - return hv_map_interrupt(device_id, level, cpu, vector, entry); + return hv_map_interrupt(hv_devid, level, cpu, vector, entry); } EXPORT_SYMBOL_GPL(hv_map_ioapic_interrupt); --=20 2.51.2.vfs.0.1 From nobody Sat Feb 7 15:15:18 2026 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 76760366552; Tue, 20 Jan 2026 06:43:33 +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=1768891426; cv=none; b=AXRLWIwTEP+yC8T5KkbYQR9/H70ZC7GKUhy+rnF17rv0WrlrzYddUSUgCDaHccD4/6ZzYwcT32H/8IAFVfO4Ss1H+roLw8KPmZXbgmOpc/OzgQAiYQlCK3e5Y9UOt0rf91Vy+y9Q/FcXYdB24VNgI6ZDe55O+ffYWOztLSoi4lg= ARC-Message-Signature: i=1; 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Mon, 19 Jan 2026 22:43:30 -0800 (PST) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 0AF6020B716C DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1768891410; bh=GY/3BAplObLOWLiMmMhdzuiyonlo2hPySFg8J0DmMRg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=OyE5IrEXEydCDRpaah6ewzB23X17QX/RjBGB29tQkSo3l2hB8CFiO6YmqRj0708qp EfkZmdhRxrU1OIR3rZ4960CcronEfP/kE700rK8djoXhNeQhKHhgnxNT6HJRWUZ94I Oo0gffN1n2BT7OZCtpE2b2IsuJYEKTvJMyFBk6po= From: Mukesh R To: linux-kernel@vger.kernel.org, linux-hyperv@vger.kernel.org, linux-arm-kernel@lists.infradead.org, iommu@lists.linux.dev, linux-pci@vger.kernel.org, linux-arch@vger.kernel.org Cc: kys@microsoft.com, haiyangz@microsoft.com, wei.liu@kernel.org, decui@microsoft.com, longli@microsoft.com, catalin.marinas@arm.com, will@kernel.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com, joro@8bytes.org, lpieralisi@kernel.org, kwilczynski@kernel.org, mani@kernel.org, robh@kernel.org, bhelgaas@google.com, arnd@arndb.de, nunodasneves@linux.microsoft.com, mhklinux@outlook.com, romank@linux.microsoft.com Subject: [PATCH v0 03/15] x86/hyperv: add insufficient memory support in irqdomain.c Date: Mon, 19 Jan 2026 22:42:18 -0800 Message-ID: <20260120064230.3602565-4-mrathor@linux.microsoft.com> X-Mailer: git-send-email 2.51.2.vfs.0.1 In-Reply-To: <20260120064230.3602565-1-mrathor@linux.microsoft.com> References: <20260120064230.3602565-1-mrathor@linux.microsoft.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Mukesh Rathor Passthru exposes insufficient memory hypercall failure in the current map device interrupt hypercall. In case of such a failure, we must deposit more memory and redo the hypercall. Add support for that. Deposit memory needs partition id, make that a parameter to the map interrupt function. Signed-off-by: Mukesh Rathor --- arch/x86/hyperv/irqdomain.c | 38 +++++++++++++++++++++++++++++++------ 1 file changed, 32 insertions(+), 6 deletions(-) diff --git a/arch/x86/hyperv/irqdomain.c b/arch/x86/hyperv/irqdomain.c index f6b61483b3b8..ccbe5848a28f 100644 --- a/arch/x86/hyperv/irqdomain.c +++ b/arch/x86/hyperv/irqdomain.c @@ -13,8 +13,9 @@ #include #include =20 -static int hv_map_interrupt(union hv_device_id hv_devid, bool level, - int cpu, int vector, struct hv_interrupt_entry *ret_entry) +static u64 hv_map_interrupt_hcall(u64 ptid, union hv_device_id hv_devid, + bool level, int cpu, int vector, + struct hv_interrupt_entry *ret_entry) { struct hv_input_map_device_interrupt *input; struct hv_output_map_device_interrupt *output; @@ -30,8 +31,10 @@ static int hv_map_interrupt(union hv_device_id hv_devid,= bool level, =20 intr_desc =3D &input->interrupt_descriptor; memset(input, 0, sizeof(*input)); - input->partition_id =3D hv_current_partition_id; + + input->partition_id =3D ptid; input->device_id =3D hv_devid.as_uint64; + intr_desc->interrupt_type =3D HV_X64_INTERRUPT_TYPE_FIXED; intr_desc->vector_count =3D 1; intr_desc->target.vector =3D vector; @@ -64,6 +67,28 @@ static int hv_map_interrupt(union hv_device_id hv_devid,= bool level, =20 local_irq_restore(flags); =20 + return status; +} + +static int hv_map_interrupt(u64 ptid, union hv_device_id device_id, bool l= evel, + int cpu, int vector, + struct hv_interrupt_entry *ret_entry) +{ + u64 status; + int rc, deposit_pgs =3D 16; /* don't loop forever */ + + while (deposit_pgs--) { + status =3D hv_map_interrupt_hcall(ptid, device_id, level, cpu, + vector, ret_entry); + + if (hv_result(status) !=3D HV_STATUS_INSUFFICIENT_MEMORY) + break; + + rc =3D hv_call_deposit_pages(NUMA_NO_NODE, ptid, 1); + if (rc) + break; + }; + if (!hv_result_success(status)) hv_status_err(status, "\n"); =20 @@ -199,8 +224,8 @@ int hv_map_msi_interrupt(struct irq_data *data, hv_devid =3D hv_build_devid_type_pci(pdev); cpu =3D cpumask_first(irq_data_get_effective_affinity_mask(data)); =20 - return hv_map_interrupt(hv_devid, false, cpu, cfg->vector, - out_entry ? out_entry : &dummy); + return hv_map_interrupt(hv_current_partition_id, hv_devid, false, cpu, + cfg->vector, out_entry ? out_entry : &dummy); } EXPORT_SYMBOL_GPL(hv_map_msi_interrupt); =20 @@ -422,6 +447,7 @@ int hv_map_ioapic_interrupt(int ioapic_id, bool level, = int cpu, int vector, hv_devid.device_type =3D HV_DEVICE_TYPE_IOAPIC; hv_devid.ioapic.ioapic_id =3D (u8)ioapic_id; =20 - return hv_map_interrupt(hv_devid, level, cpu, vector, entry); + return hv_map_interrupt(hv_current_partition_id, hv_devid, level, cpu, + vector, entry); } EXPORT_SYMBOL_GPL(hv_map_ioapic_interrupt); --=20 2.51.2.vfs.0.1 From nobody Sat Feb 7 15:15:18 2026 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id B0D3438B7DE; Tue, 20 Jan 2026 06:43:32 +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=1768891426; cv=none; b=S9QDc6ra/L/gWhEqGG2qVbK8L9Mnwwxi4E++f25nYJYRsURAx/pSQl3jf6s8w+wzbfOMC2zhYch6uSrFW2d9Ak28ownOjafzpoo6m8K2OJ5F6pjt2tTUaDmp32tG3cnlG/6Q/T1wPi1wfvU/So8skSeZTstWvsG376Iiy0P+oTo= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768891426; c=relaxed/simple; bh=JMe5l6JLGKke32CXM+7TnJxiKSkmgTGBXD5PSTwA/SE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=BYKO/rDDHaQOCOiR3sXKSott1cwYHCKyVOsb5GDoxV5WRDNmdg8K/7Jl9+8Dn/hwYLMeXQi2p1E+6wIzsRyHzxeRaPoa0KsRooBU7wGb/aL/hgOWkr5ko1M1ZTRW7CQ+4ObWUVqM51lgD3ScBxFRh+oJcxa7hBULk5NSW7naCm4= 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=AFMIPpY6; 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="AFMIPpY6" Received: from mrdev.corp.microsoft.com (192-184-212-33.fiber.dynamic.sonic.net [192.184.212.33]) by linux.microsoft.com (Postfix) with ESMTPSA id 305DB20B716D; Mon, 19 Jan 2026 22:43:31 -0800 (PST) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 305DB20B716D DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1768891411; bh=usRPxgl1amP/v9n1SLf7SAiI18LuyGFVnItwiHNDJxo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=AFMIPpY6TAiuIZv+8jTFocdvb6bDbOjidIdTfShgZ/xxmsSw89ShdkgVGXcpmIi0a uqU3YdVEEs1oymmxBJNjCltMFdDLzFigaa4fuIlemUvg+4jc3mQbADgxz0xjUC5u9B GG7ZGEq4SoiolDL1XVlZ5e9MX+LXwD8K65AF0h+A= From: Mukesh R To: linux-kernel@vger.kernel.org, linux-hyperv@vger.kernel.org, linux-arm-kernel@lists.infradead.org, iommu@lists.linux.dev, linux-pci@vger.kernel.org, linux-arch@vger.kernel.org Cc: kys@microsoft.com, haiyangz@microsoft.com, wei.liu@kernel.org, decui@microsoft.com, longli@microsoft.com, catalin.marinas@arm.com, will@kernel.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com, joro@8bytes.org, lpieralisi@kernel.org, kwilczynski@kernel.org, mani@kernel.org, robh@kernel.org, bhelgaas@google.com, arnd@arndb.de, nunodasneves@linux.microsoft.com, mhklinux@outlook.com, romank@linux.microsoft.com Subject: [PATCH v0 04/15] mshv: Provide a way to get partition id if running in a VMM process Date: Mon, 19 Jan 2026 22:42:19 -0800 Message-ID: <20260120064230.3602565-5-mrathor@linux.microsoft.com> X-Mailer: git-send-email 2.51.2.vfs.0.1 In-Reply-To: <20260120064230.3602565-1-mrathor@linux.microsoft.com> References: <20260120064230.3602565-1-mrathor@linux.microsoft.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Mukesh Rathor Many PCI passthru related hypercalls require partition id of the target guest. Guests are actually managed by MSHV driver and the partition id is only maintained there. Add a field in the partition struct in MSHV driver to save the tgid of the VMM process creating the partition, and add a function there to retrieve partition id if valid VMM tgid. Signed-off-by: Mukesh Rathor --- drivers/hv/mshv_root.h | 1 + drivers/hv/mshv_root_main.c | 35 +++++++++++++++++++++++++++------- include/asm-generic/mshyperv.h | 1 + 3 files changed, 30 insertions(+), 7 deletions(-) diff --git a/drivers/hv/mshv_root.h b/drivers/hv/mshv_root.h index 3c1d88b36741..c3753b009fd8 100644 --- a/drivers/hv/mshv_root.h +++ b/drivers/hv/mshv_root.h @@ -134,6 +134,7 @@ struct mshv_partition { =20 struct mshv_girq_routing_table __rcu *pt_girq_tbl; u64 isolation_type; + pid_t pt_vmm_tgid; bool import_completed; bool pt_initialized; }; diff --git a/drivers/hv/mshv_root_main.c b/drivers/hv/mshv_root_main.c index 1134a82c7881..83c7bad269a0 100644 --- a/drivers/hv/mshv_root_main.c +++ b/drivers/hv/mshv_root_main.c @@ -1823,6 +1823,20 @@ mshv_partition_release(struct inode *inode, struct f= ile *filp) return 0; } =20 +/* Given a process tgid, return partition id if it is a VMM process */ +u64 mshv_pid_to_partid(pid_t tgid) +{ + struct mshv_partition *pt; + int i; + + hash_for_each_rcu(mshv_root.pt_htable, i, pt, pt_hnode) + if (pt->pt_vmm_tgid =3D=3D tgid) + return pt->pt_id; + + return HV_PARTITION_ID_INVALID; +} +EXPORT_SYMBOL_GPL(mshv_pid_to_partid); + static int add_partition(struct mshv_partition *partition) { @@ -1987,13 +2001,20 @@ mshv_ioctl_create_partition(void __user *user_arg, = struct device *module_dev) goto delete_partition; =20 ret =3D mshv_init_async_handler(partition); - if (!ret) { - ret =3D FD_ADD(O_CLOEXEC, anon_inode_getfile("mshv_partition", - &mshv_partition_fops, - partition, O_RDWR)); - if (ret >=3D 0) - return ret; - } + if (ret) + goto rem_partition; + + ret =3D FD_ADD(O_CLOEXEC, anon_inode_getfile("mshv_partition", + &mshv_partition_fops, + partition, O_RDWR)); + if (ret < 0) + goto rem_partition; + + partition->pt_vmm_tgid =3D current->tgid; + + return ret; + +rem_partition: remove_partition(partition); delete_partition: hv_call_delete_partition(partition->pt_id); diff --git a/include/asm-generic/mshyperv.h b/include/asm-generic/mshyperv.h index ecedab554c80..e46a38916e76 100644 --- a/include/asm-generic/mshyperv.h +++ b/include/asm-generic/mshyperv.h @@ -211,6 +211,7 @@ void __init ms_hyperv_late_init(void); int hv_common_cpu_init(unsigned int cpu); int hv_common_cpu_die(unsigned int cpu); void hv_identify_partition_type(void); +u64 mshv_pid_to_partid(pid_t tgid); =20 /** * hv_cpu_number_to_vp_number() - Map CPU to VP. --=20 2.51.2.vfs.0.1 From nobody Sat Feb 7 15:15:18 2026 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 332CE3921EB; Tue, 20 Jan 2026 06:43:45 +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=1768891428; cv=none; b=qtEBVWl7UM1+6OlkfIdKYsX8QgmuMuHySqW1esGkq1ftKphdFN+mFuWRYSM+Q57T+dOb/Dk8a6O6O+RLhsEwNzm7v2rOERcFWOcW/hBzUL/HyULxuZCHiLAKeIBbLR1Z6bDrBGj2I2JtDomlcCzN23soR8aiKGaQA6wKEewzADA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768891428; c=relaxed/simple; bh=a+5I56PNpIKKks7EE6l2KDH8xIKcZwQ18GISN5Z/VWw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; 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Mon, 19 Jan 2026 22:43:32 -0800 (PST) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 54B4720B716E DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1768891413; bh=FPdcZ3oYYb4ZG+PhlxYF87J7HHXsFXSeD2DjQ2CVDUs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=MiATsc3swd7iNJmjeFF3w4IDEsPYdWmb2J6SCPlMQQO32Pnrw5LP6U52eGSSappj2 TqyitrZ2rdhmWEEejwZfN2zcFSnJKFrZOP8otPcC8LrvT3klwyLhWnqRm1HiJDYpAf xzPjuypRaaY68PG9Ltq37rP3R3k62wGFPm9I0euY= From: Mukesh R To: linux-kernel@vger.kernel.org, linux-hyperv@vger.kernel.org, linux-arm-kernel@lists.infradead.org, iommu@lists.linux.dev, linux-pci@vger.kernel.org, linux-arch@vger.kernel.org Cc: kys@microsoft.com, haiyangz@microsoft.com, wei.liu@kernel.org, decui@microsoft.com, longli@microsoft.com, catalin.marinas@arm.com, will@kernel.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com, joro@8bytes.org, lpieralisi@kernel.org, kwilczynski@kernel.org, mani@kernel.org, robh@kernel.org, bhelgaas@google.com, arnd@arndb.de, nunodasneves@linux.microsoft.com, mhklinux@outlook.com, romank@linux.microsoft.com Subject: [PATCH v0 05/15] mshv: Declarations and definitions for VFIO-MSHV bridge device Date: Mon, 19 Jan 2026 22:42:20 -0800 Message-ID: <20260120064230.3602565-6-mrathor@linux.microsoft.com> X-Mailer: git-send-email 2.51.2.vfs.0.1 In-Reply-To: <20260120064230.3602565-1-mrathor@linux.microsoft.com> References: <20260120064230.3602565-1-mrathor@linux.microsoft.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Mukesh Rathor Add data structs needed by the subsequent patch that introduces a new module to implement VFIO-MSHV pseudo device. Signed-off-by: Mukesh Rathor --- drivers/hv/mshv_root.h | 23 +++++++++++++++++++++++ include/uapi/linux/mshv.h | 31 +++++++++++++++++++++++++++++++ 2 files changed, 54 insertions(+) diff --git a/drivers/hv/mshv_root.h b/drivers/hv/mshv_root.h index c3753b009fd8..42e1da1d545b 100644 --- a/drivers/hv/mshv_root.h +++ b/drivers/hv/mshv_root.h @@ -220,6 +220,29 @@ struct port_table_info { }; }; =20 +struct mshv_device { + const struct mshv_device_ops *device_ops; + struct mshv_partition *device_pt; + void *device_private; + struct hlist_node device_ptnode; +}; + +struct mshv_device_ops { + const char *device_name; + long (*device_create)(struct mshv_device *dev, u32 type); + void (*device_release)(struct mshv_device *dev); + long (*device_set_attr)(struct mshv_device *dev, + struct mshv_device_attr *attr); + long (*device_has_attr)(struct mshv_device *dev, + struct mshv_device_attr *attr); +}; + +extern struct mshv_device_ops mshv_vfio_device_ops; +int mshv_vfio_ops_init(void); +void mshv_vfio_ops_exit(void); +long mshv_partition_ioctl_create_device(struct mshv_partition *partition, + void __user *user_args); + int mshv_update_routing_table(struct mshv_partition *partition, const struct mshv_user_irq_entry *entries, unsigned int numents); diff --git a/include/uapi/linux/mshv.h b/include/uapi/linux/mshv.h index dee3ece28ce5..b7b10f9e2896 100644 --- a/include/uapi/linux/mshv.h +++ b/include/uapi/linux/mshv.h @@ -252,6 +252,7 @@ struct mshv_root_hvcall { #define MSHV_GET_GPAP_ACCESS_BITMAP _IOWR(MSHV_IOCTL, 0x06, struct mshv_gp= ap_access_bitmap) /* Generic hypercall */ #define MSHV_ROOT_HVCALL _IOWR(MSHV_IOCTL, 0x07, struct mshv_root_hvcall) +#define MSHV_CREATE_DEVICE _IOWR(MSHV_IOCTL, 0x08, struct mshv_create_dev= ice) =20 /* ******************************** @@ -402,4 +403,34 @@ struct mshv_sint_mask { /* hv_hvcall device */ #define MSHV_HVCALL_SETUP _IOW(MSHV_IOCTL, 0x1E, struct mshv_vtl_hv= call_setup) #define MSHV_HVCALL _IOWR(MSHV_IOCTL, 0x1F, struct mshv_vtl_h= vcall) + +/* device passhthru */ +#define MSHV_CREATE_DEVICE_TEST 1 + +enum { + MSHV_DEV_TYPE_VFIO, + MSHV_DEV_TYPE_MAX, +}; + +struct mshv_create_device { + __u32 type; /* in: MSHV_DEV_TYPE_xxx */ + __u32 fd; /* out: device handle */ + __u32 flags; /* in: MSHV_CREATE_DEVICE_xxx */ +}; + +#define MSHV_DEV_VFIO_FILE 1 +#define MSHV_DEV_VFIO_FILE_ADD 1 +#define MSHV_DEV_VFIO_FILE_DEL 2 + +struct mshv_device_attr { + __u32 flags; /* no flags currently defined */ + __u32 group; /* device-defined */ + __u64 attr; /* group-defined */ + __u64 addr; /* userspace address of attr data */ +}; + +/* Device fds created with MSHV_CREATE_DEVICE */ +#define MSHV_SET_DEVICE_ATTR _IOW(MSHV_IOCTL, 0x00, struct mshv_device_att= r) +#define MSHV_HAS_DEVICE_ATTR _IOW(MSHV_IOCTL, 0x01, struct mshv_device_att= r) + #endif --=20 2.51.2.vfs.0.1 From nobody Sat Feb 7 15:15:18 2026 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 32E763803C9; Tue, 20 Jan 2026 06:43:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=13.77.154.182 ARC-Seal: i=1; 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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="IOvVNIdh" Received: from mrdev.corp.microsoft.com (192-184-212-33.fiber.dynamic.sonic.net [192.184.212.33]) by linux.microsoft.com (Postfix) with ESMTPSA id B615E20B716F; Mon, 19 Jan 2026 22:43:33 -0800 (PST) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com B615E20B716F DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1768891414; bh=FwXH04ojEJxzpdDZwfeULNXdgZ4dyhCYxfw3tXdVy3E=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=IOvVNIdhQm1FzPXkTQDr6pHRkzL3ArhoH+uoR99cwC5MHH22g9j3Kl66U8jUWNDCP k5Y9DlpfYNsMYamxE6UKNWHlrDXpfhR5dsom3uwq/vPtCAsjkiqt4DXdL6AWhq3aOF L6r1zY4aWR9/vJsgZZzPvwf9FsiwH55J+H45oDPk= From: Mukesh R To: linux-kernel@vger.kernel.org, linux-hyperv@vger.kernel.org, linux-arm-kernel@lists.infradead.org, iommu@lists.linux.dev, linux-pci@vger.kernel.org, linux-arch@vger.kernel.org Cc: kys@microsoft.com, haiyangz@microsoft.com, wei.liu@kernel.org, decui@microsoft.com, longli@microsoft.com, catalin.marinas@arm.com, will@kernel.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com, joro@8bytes.org, lpieralisi@kernel.org, kwilczynski@kernel.org, mani@kernel.org, robh@kernel.org, bhelgaas@google.com, arnd@arndb.de, nunodasneves@linux.microsoft.com, mhklinux@outlook.com, romank@linux.microsoft.com Subject: [PATCH v0 06/15] mshv: Implement mshv bridge device for VFIO Date: Mon, 19 Jan 2026 22:42:21 -0800 Message-ID: <20260120064230.3602565-7-mrathor@linux.microsoft.com> X-Mailer: git-send-email 2.51.2.vfs.0.1 In-Reply-To: <20260120064230.3602565-1-mrathor@linux.microsoft.com> References: <20260120064230.3602565-1-mrathor@linux.microsoft.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Mukesh Rathor Add a new file to implement VFIO-MSHV bridge pseudo device. These functions are called in the VFIO framework, and credits to kvm/vfio.c as this file was adapted from it. Original author: Wei Liu (Slightly modified from the original version). Signed-off-by: Mukesh Rathor --- drivers/hv/Makefile | 3 +- drivers/hv/mshv_vfio.c | 210 +++++++++++++++++++++++++++++++++++++++++ 2 files changed, 212 insertions(+), 1 deletion(-) create mode 100644 drivers/hv/mshv_vfio.c diff --git a/drivers/hv/Makefile b/drivers/hv/Makefile index a49f93c2d245..eae003c4cb8f 100644 --- a/drivers/hv/Makefile +++ b/drivers/hv/Makefile @@ -14,7 +14,8 @@ hv_vmbus-y :=3D vmbus_drv.o \ hv_vmbus-$(CONFIG_HYPERV_TESTING) +=3D hv_debugfs.o hv_utils-y :=3D hv_util.o hv_kvp.o hv_snapshot.o hv_utils_transport.o mshv_root-y :=3D mshv_root_main.o mshv_synic.o mshv_eventfd.o mshv_irq.o \ - mshv_root_hv_call.o mshv_portid_table.o mshv_regions.o + mshv_root_hv_call.o mshv_portid_table.o mshv_regions.o \ + mshv_vfio.o mshv_vtl-y :=3D mshv_vtl_main.o =20 # Code that must be built-in diff --git a/drivers/hv/mshv_vfio.c b/drivers/hv/mshv_vfio.c new file mode 100644 index 000000000000..6ea4d99a3bd2 --- /dev/null +++ b/drivers/hv/mshv_vfio.c @@ -0,0 +1,210 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * VFIO-MSHV bridge pseudo device + * + * Heavily inspired by the VFIO-KVM bridge pseudo device. + */ +#include +#include +#include +#include +#include +#include +#include + +#include "mshv.h" +#include "mshv_root.h" + +struct mshv_vfio_file { + struct list_head node; + struct file *file; /* list of struct mshv_vfio_file */ +}; + +struct mshv_vfio { + struct list_head file_list; + struct mutex lock; +}; + +static bool mshv_vfio_file_is_valid(struct file *file) +{ + bool (*fn)(struct file *file); + bool ret; + + fn =3D symbol_get(vfio_file_is_valid); + if (!fn) + return false; + + ret =3D fn(file); + + symbol_put(vfio_file_is_valid); + + return ret; +} + +static long mshv_vfio_file_add(struct mshv_device *mshvdev, unsigned int f= d) +{ + struct mshv_vfio *mshv_vfio =3D mshvdev->device_private; + struct mshv_vfio_file *mvf; + struct file *filp; + long ret =3D 0; + + filp =3D fget(fd); + if (!filp) + return -EBADF; + + /* Ensure the FD is a vfio FD. */ + if (!mshv_vfio_file_is_valid(filp)) { + ret =3D -EINVAL; + goto out_fput; + } + + mutex_lock(&mshv_vfio->lock); + + list_for_each_entry(mvf, &mshv_vfio->file_list, node) { + if (mvf->file =3D=3D filp) { + ret =3D -EEXIST; + goto out_unlock; + } + } + + mvf =3D kzalloc(sizeof(*mvf), GFP_KERNEL_ACCOUNT); + if (!mvf) { + ret =3D -ENOMEM; + goto out_unlock; + } + + mvf->file =3D get_file(filp); + list_add_tail(&mvf->node, &mshv_vfio->file_list); + +out_unlock: + mutex_unlock(&mshv_vfio->lock); +out_fput: + fput(filp); + return ret; +} + +static long mshv_vfio_file_del(struct mshv_device *mshvdev, unsigned int f= d) +{ + struct mshv_vfio *mshv_vfio =3D mshvdev->device_private; + struct mshv_vfio_file *mvf; + long ret; + + CLASS(fd, f)(fd); + + if (fd_empty(f)) + return -EBADF; + + ret =3D -ENOENT; + mutex_lock(&mshv_vfio->lock); + + list_for_each_entry(mvf, &mshv_vfio->file_list, node) { + if (mvf->file !=3D fd_file(f)) + continue; + + list_del(&mvf->node); + fput(mvf->file); + kfree(mvf); + ret =3D 0; + break; + } + + mutex_unlock(&mshv_vfio->lock); + return ret; +} + +static long mshv_vfio_set_file(struct mshv_device *mshvdev, long attr, + void __user *arg) +{ + int32_t __user *argp =3D arg; + int32_t fd; + + switch (attr) { + case MSHV_DEV_VFIO_FILE_ADD: + if (get_user(fd, argp)) + return -EFAULT; + return mshv_vfio_file_add(mshvdev, fd); + + case MSHV_DEV_VFIO_FILE_DEL: + if (get_user(fd, argp)) + return -EFAULT; + return mshv_vfio_file_del(mshvdev, fd); + } + + return -ENXIO; +} + +static long mshv_vfio_set_attr(struct mshv_device *mshvdev, + struct mshv_device_attr *attr) +{ + switch (attr->group) { + case MSHV_DEV_VFIO_FILE: + return mshv_vfio_set_file(mshvdev, attr->attr, + u64_to_user_ptr(attr->addr)); + } + + return -ENXIO; +} + +static long mshv_vfio_has_attr(struct mshv_device *mshvdev, + struct mshv_device_attr *attr) +{ + switch (attr->group) { + case MSHV_DEV_VFIO_FILE: + switch (attr->attr) { + case MSHV_DEV_VFIO_FILE_ADD: + case MSHV_DEV_VFIO_FILE_DEL: + return 0; + } + + break; + } + + return -ENXIO; +} + +static long mshv_vfio_create_device(struct mshv_device *mshvdev, u32 type) +{ + struct mshv_device *tmp; + struct mshv_vfio *mshv_vfio; + + /* Only one VFIO "device" per VM */ + hlist_for_each_entry(tmp, &mshvdev->device_pt->pt_devices, + device_ptnode) + if (tmp->device_ops =3D=3D &mshv_vfio_device_ops) + return -EBUSY; + + mshv_vfio =3D kzalloc(sizeof(*mshv_vfio), GFP_KERNEL_ACCOUNT); + if (mshv_vfio =3D=3D NULL) + return -ENOMEM; + + INIT_LIST_HEAD(&mshv_vfio->file_list); + mutex_init(&mshv_vfio->lock); + + mshvdev->device_private =3D mshv_vfio; + + return 0; +} + +/* This is called from mshv_device_fop_release() */ +static void mshv_vfio_release_device(struct mshv_device *mshvdev) +{ + struct mshv_vfio *mv =3D mshvdev->device_private; + struct mshv_vfio_file *mvf, *tmp; + + list_for_each_entry_safe(mvf, tmp, &mv->file_list, node) { + fput(mvf->file); + list_del(&mvf->node); + kfree(mvf); + } + + kfree(mv); + kfree(mshvdev); +} + +struct mshv_device_ops mshv_vfio_device_ops =3D { + .device_name =3D "mshv-vfio", + .device_create =3D mshv_vfio_create_device, + .device_release =3D mshv_vfio_release_device, + .device_set_attr =3D mshv_vfio_set_attr, + .device_has_attr =3D mshv_vfio_has_attr, +}; --=20 2.51.2.vfs.0.1 From nobody Sat Feb 7 15:15:18 2026 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 69D60387564; Tue, 20 Jan 2026 06:43:42 +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=1768891430; cv=none; b=RXVaPxqKrFa67B0z5JSXglbU0xrAP1ChzPFyowW4NilgqMTRD7+IUy7fpRdQN8Szbl6VOCLlpRQX0fK7BKsw9uEzjSFIsjPtKz8WqgaatlAb2vzRHOzxFEPUv5cDOX7LokjiSit3gATkSXzHwz+q4P/utOMcM8OMI7mDEwiWIUQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768891430; c=relaxed/simple; bh=5lHBBMfqPqoiY8Jb5i1UmMDSCU6QId/cFabKNEhXapA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=B9brgOlpVwpaJUVBfo7OwNJR7EzIEaFSujNcmhnFD7zv3tSmn6/gBhV1Ew1XvTHRSS4WVYLND8mY+AakwjYF/fVKNGMIsWwyGp1ugrHBpf/yyTIJ9cqGO7KJub1cBsJP2mb8ilr9XTnxv/v3MfVqxuiq933vaZsYywYdOKvQXJg= 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=XooknD8V; 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="XooknD8V" Received: from mrdev.corp.microsoft.com (192-184-212-33.fiber.dynamic.sonic.net [192.184.212.33]) by linux.microsoft.com (Postfix) with ESMTPSA id F3B4F20B7170; Mon, 19 Jan 2026 22:43:34 -0800 (PST) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com F3B4F20B7170 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1768891415; bh=zpXyH34CFeKZeTaTWBElXlgUbMpP958BejYtbygF9WU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=XooknD8V3y1L7GC5cut7FI2hLyVvn6UK2r3zNP70pOOrJOGkL2XgdHyUFQhkvqH+s a2RAD3LH4gUbnfx4u/9xJnauVpk+rbZvmVon1tdkvwqWrzcIdMVTfcOr9i82ENiIG+ 9hTmsE68dqA36HuiiMpMrCAkEEFwOF3W1KpplTro= From: Mukesh R To: linux-kernel@vger.kernel.org, linux-hyperv@vger.kernel.org, linux-arm-kernel@lists.infradead.org, iommu@lists.linux.dev, linux-pci@vger.kernel.org, linux-arch@vger.kernel.org Cc: kys@microsoft.com, haiyangz@microsoft.com, wei.liu@kernel.org, decui@microsoft.com, longli@microsoft.com, catalin.marinas@arm.com, will@kernel.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com, joro@8bytes.org, lpieralisi@kernel.org, kwilczynski@kernel.org, mani@kernel.org, robh@kernel.org, bhelgaas@google.com, arnd@arndb.de, nunodasneves@linux.microsoft.com, mhklinux@outlook.com, romank@linux.microsoft.com Subject: [PATCH v0 07/15] mshv: Add ioctl support for MSHV-VFIO bridge device Date: Mon, 19 Jan 2026 22:42:22 -0800 Message-ID: <20260120064230.3602565-8-mrathor@linux.microsoft.com> X-Mailer: git-send-email 2.51.2.vfs.0.1 In-Reply-To: <20260120064230.3602565-1-mrathor@linux.microsoft.com> References: <20260120064230.3602565-1-mrathor@linux.microsoft.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Mukesh Rathor Add ioctl support for creating MSHV devices for a paritition. At present only VFIO device types are supported, but more could be added. At a high level, a partition ioctl to create device verifies it is of type VFIO and does some setup for bridge code in mshv_vfio.c. Adapted from KVM device ioctls. Credits: Original author: Wei Liu NB: Slightly modified from the original version. Signed-off-by: Mukesh Rathor --- drivers/hv/mshv_root_main.c | 126 ++++++++++++++++++++++++++++++++++++ 1 file changed, 126 insertions(+) diff --git a/drivers/hv/mshv_root_main.c b/drivers/hv/mshv_root_main.c index 83c7bad269a0..27313419828d 100644 --- a/drivers/hv/mshv_root_main.c +++ b/drivers/hv/mshv_root_main.c @@ -1551,6 +1551,129 @@ mshv_partition_ioctl_initialize(struct mshv_partiti= on *partition) return ret; } =20 +static long mshv_device_attr_ioctl(struct mshv_device *mshv_dev, int cmd, + ulong uarg) +{ + struct mshv_device_attr attr; + const struct mshv_device_ops *devops =3D mshv_dev->device_ops; + + if (copy_from_user(&attr, (void __user *)uarg, sizeof(attr))) + return -EFAULT; + + switch (cmd) { + case MSHV_SET_DEVICE_ATTR: + if (devops->device_set_attr) + return devops->device_set_attr(mshv_dev, &attr); + break; + case MSHV_HAS_DEVICE_ATTR: + if (devops->device_has_attr) + return devops->device_has_attr(mshv_dev, &attr); + break; + } + + return -EPERM; +} + +static long mshv_device_fop_ioctl(struct file *filp, unsigned int cmd, + ulong uarg) +{ + struct mshv_device *mshv_dev =3D filp->private_data; + + switch (cmd) { + case MSHV_SET_DEVICE_ATTR: + case MSHV_HAS_DEVICE_ATTR: + return mshv_device_attr_ioctl(mshv_dev, cmd, uarg); + } + + return -ENOTTY; +} + +static int mshv_device_fop_release(struct inode *inode, struct file *filp) +{ + struct mshv_device *mshv_dev =3D filp->private_data; + struct mshv_partition *partition =3D mshv_dev->device_pt; + + if (mshv_dev->device_ops->device_release) { + mutex_lock(&partition->pt_mutex); + hlist_del(&mshv_dev->device_ptnode); + mshv_dev->device_ops->device_release(mshv_dev); + mutex_unlock(&partition->pt_mutex); + } + + mshv_partition_put(partition); + return 0; +} + +static const struct file_operations mshv_device_fops =3D { + .owner =3D THIS_MODULE, + .unlocked_ioctl =3D mshv_device_fop_ioctl, + .release =3D mshv_device_fop_release, +}; + +long mshv_partition_ioctl_create_device(struct mshv_partition *partition, + void __user *uarg) +{ + long rc; + struct mshv_create_device devargk; + struct mshv_device *mshv_dev; + const struct mshv_device_ops *vfio_ops; + int type; + + if (copy_from_user(&devargk, uarg, sizeof(devargk))) { + rc =3D -EFAULT; + goto out; + } + + /* At present, only VFIO is supported */ + if (devargk.type !=3D MSHV_DEV_TYPE_VFIO) { + rc =3D -ENODEV; + goto out; + } + + if (devargk.flags & MSHV_CREATE_DEVICE_TEST) { + rc =3D 0; + goto out; + } + + mshv_dev =3D kzalloc(sizeof(*mshv_dev), GFP_KERNEL_ACCOUNT); + if (mshv_dev =3D=3D NULL) { + rc =3D -ENOMEM; + goto out; + } + + vfio_ops =3D &mshv_vfio_device_ops; + mshv_dev->device_ops =3D vfio_ops; + mshv_dev->device_pt =3D partition; + + rc =3D vfio_ops->device_create(mshv_dev, type); + if (rc < 0) { + kfree(mshv_dev); + goto out; + } + + hlist_add_head(&mshv_dev->device_ptnode, &partition->pt_devices); + + mshv_partition_get(partition); + rc =3D anon_inode_getfd(vfio_ops->device_name, &mshv_device_fops, + mshv_dev, O_RDWR | O_CLOEXEC); + if (rc < 0) { + mshv_partition_put(partition); + hlist_del(&mshv_dev->device_ptnode); + vfio_ops->device_release(mshv_dev); + goto out; + } + + devargk.fd =3D rc; + rc =3D 0; + + if (copy_to_user(uarg, &devargk, sizeof(devargk))) { + rc =3D -EFAULT; + goto out; + } +out: + return rc; +} + static long mshv_partition_ioctl(struct file *filp, unsigned int ioctl, unsigned long = arg) { @@ -1587,6 +1710,9 @@ mshv_partition_ioctl(struct file *filp, unsigned int = ioctl, unsigned long arg) case MSHV_ROOT_HVCALL: ret =3D mshv_ioctl_passthru_hvcall(partition, true, uarg); break; + case MSHV_CREATE_DEVICE: + ret =3D mshv_partition_ioctl_create_device(partition, uarg); + break; default: ret =3D -ENOTTY; } --=20 2.51.2.vfs.0.1 From nobody Sat Feb 7 15:15:18 2026 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 967AF38E106; Tue, 20 Jan 2026 06:43:42 +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=1768891429; cv=none; b=tSKY3dywheF2saq4diFQyQ+Hp/QfcQepRdSjPwcdi2uLfk6XzZg7pOVORrusg3PYprgOLK2WzfkbNuGittJidIxyamPS1x+wVmjH3/fUQ8LGijYBr4K1+dLKw39UYdk+E/UHEdMZmKUodjO0WGenyJC92KWVPEa6q+hhfVjUoXQ= ARC-Message-Signature: i=1; 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Mon, 19 Jan 2026 22:43:36 -0800 (PST) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 30F3B20B7171 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1768891416; bh=6AAp/ykXusoNZA7ncLQ0JBdGDrm8nyxPjzKKo/+ZvTQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=DcfTkOJm/guybBs88Dp9gw9NXcNzXsgtq0GsljuOOVQkF4lfCPXMBvaMaPidC8my4 vMf5jkI5R+a9XO5H2lX/akgtSVOeWt/LXHvpu0DzQ8ZZxivzKQTJnVNBZ6PO57GXoD WPLau1cY0IauA77XhHi9bXHMaY7BdpIvknVlOvfo= From: Mukesh R To: linux-kernel@vger.kernel.org, linux-hyperv@vger.kernel.org, linux-arm-kernel@lists.infradead.org, iommu@lists.linux.dev, linux-pci@vger.kernel.org, linux-arch@vger.kernel.org Cc: kys@microsoft.com, haiyangz@microsoft.com, wei.liu@kernel.org, decui@microsoft.com, longli@microsoft.com, catalin.marinas@arm.com, will@kernel.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com, joro@8bytes.org, lpieralisi@kernel.org, kwilczynski@kernel.org, mani@kernel.org, robh@kernel.org, bhelgaas@google.com, arnd@arndb.de, nunodasneves@linux.microsoft.com, mhklinux@outlook.com, romank@linux.microsoft.com Subject: [PATCH v0 08/15] PCI: hv: rename hv_compose_msi_msg to hv_vmbus_compose_msi_msg Date: Mon, 19 Jan 2026 22:42:23 -0800 Message-ID: <20260120064230.3602565-9-mrathor@linux.microsoft.com> X-Mailer: git-send-email 2.51.2.vfs.0.1 In-Reply-To: <20260120064230.3602565-1-mrathor@linux.microsoft.com> References: <20260120064230.3602565-1-mrathor@linux.microsoft.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Mukesh Rathor Main change here is to rename hv_compose_msi_msg to hv_vmbus_compose_msi_msg as we introduce hv_compose_msi_msg in upcoming patches that builds MSI messages for both VMBus and non-VMBus cases. VMBus is not used on baremetal root partition for example. While at it, replace spaces with tabs and fix some formatting involving excessive line wraps. There is no functional change. Signed-off-by: Mukesh Rathor --- drivers/pci/controller/pci-hyperv.c | 95 +++++++++++++++-------------- 1 file changed, 48 insertions(+), 47 deletions(-) diff --git a/drivers/pci/controller/pci-hyperv.c b/drivers/pci/controller/p= ci-hyperv.c index 1e237d3538f9..8bc6a38c9b5a 100644 --- a/drivers/pci/controller/pci-hyperv.c +++ b/drivers/pci/controller/pci-hyperv.c @@ -30,7 +30,7 @@ * function's configuration space is zero. * * The rest of this driver mostly maps PCI concepts onto underlying Hyper-V - * facilities. For instance, the configuration space of a function exposed + * facilities. For instance, the configuration space of a function exposed * by Hyper-V is mapped into a single page of memory space, and the * read and write handlers for config space must be aware of this mechanis= m. * Similarly, device setup and teardown involves messages sent to and from @@ -109,33 +109,33 @@ enum pci_message_type { /* * Version 1.1 */ - PCI_MESSAGE_BASE =3D 0x42490000, - PCI_BUS_RELATIONS =3D PCI_MESSAGE_BASE + 0, - PCI_QUERY_BUS_RELATIONS =3D PCI_MESSAGE_BASE + 1, - PCI_POWER_STATE_CHANGE =3D PCI_MESSAGE_BASE + 4, + PCI_MESSAGE_BASE =3D 0x42490000, + PCI_BUS_RELATIONS =3D PCI_MESSAGE_BASE + 0, + PCI_QUERY_BUS_RELATIONS =3D PCI_MESSAGE_BASE + 1, + PCI_POWER_STATE_CHANGE =3D PCI_MESSAGE_BASE + 4, PCI_QUERY_RESOURCE_REQUIREMENTS =3D PCI_MESSAGE_BASE + 5, - PCI_QUERY_RESOURCE_RESOURCES =3D PCI_MESSAGE_BASE + 6, - PCI_BUS_D0ENTRY =3D PCI_MESSAGE_BASE + 7, - PCI_BUS_D0EXIT =3D PCI_MESSAGE_BASE + 8, - PCI_READ_BLOCK =3D PCI_MESSAGE_BASE + 9, - PCI_WRITE_BLOCK =3D PCI_MESSAGE_BASE + 0xA, - PCI_EJECT =3D PCI_MESSAGE_BASE + 0xB, - PCI_QUERY_STOP =3D PCI_MESSAGE_BASE + 0xC, - PCI_REENABLE =3D PCI_MESSAGE_BASE + 0xD, - PCI_QUERY_STOP_FAILED =3D PCI_MESSAGE_BASE + 0xE, - PCI_EJECTION_COMPLETE =3D PCI_MESSAGE_BASE + 0xF, - PCI_RESOURCES_ASSIGNED =3D PCI_MESSAGE_BASE + 0x10, - PCI_RESOURCES_RELEASED =3D PCI_MESSAGE_BASE + 0x11, - PCI_INVALIDATE_BLOCK =3D PCI_MESSAGE_BASE + 0x12, - PCI_QUERY_PROTOCOL_VERSION =3D PCI_MESSAGE_BASE + 0x13, - PCI_CREATE_INTERRUPT_MESSAGE =3D PCI_MESSAGE_BASE + 0x14, - PCI_DELETE_INTERRUPT_MESSAGE =3D PCI_MESSAGE_BASE + 0x15, + PCI_QUERY_RESOURCE_RESOURCES =3D PCI_MESSAGE_BASE + 6, + PCI_BUS_D0ENTRY =3D PCI_MESSAGE_BASE + 7, + PCI_BUS_D0EXIT =3D PCI_MESSAGE_BASE + 8, + PCI_READ_BLOCK =3D PCI_MESSAGE_BASE + 9, + PCI_WRITE_BLOCK =3D PCI_MESSAGE_BASE + 0xA, + PCI_EJECT =3D PCI_MESSAGE_BASE + 0xB, + PCI_QUERY_STOP =3D PCI_MESSAGE_BASE + 0xC, + PCI_REENABLE =3D PCI_MESSAGE_BASE + 0xD, + PCI_QUERY_STOP_FAILED =3D PCI_MESSAGE_BASE + 0xE, + PCI_EJECTION_COMPLETE =3D PCI_MESSAGE_BASE + 0xF, + PCI_RESOURCES_ASSIGNED =3D PCI_MESSAGE_BASE + 0x10, + PCI_RESOURCES_RELEASED =3D PCI_MESSAGE_BASE + 0x11, + PCI_INVALIDATE_BLOCK =3D PCI_MESSAGE_BASE + 0x12, + PCI_QUERY_PROTOCOL_VERSION =3D PCI_MESSAGE_BASE + 0x13, + PCI_CREATE_INTERRUPT_MESSAGE =3D PCI_MESSAGE_BASE + 0x14, + PCI_DELETE_INTERRUPT_MESSAGE =3D PCI_MESSAGE_BASE + 0x15, PCI_RESOURCES_ASSIGNED2 =3D PCI_MESSAGE_BASE + 0x16, PCI_CREATE_INTERRUPT_MESSAGE2 =3D PCI_MESSAGE_BASE + 0x17, PCI_DELETE_INTERRUPT_MESSAGE2 =3D PCI_MESSAGE_BASE + 0x18, /* unused */ PCI_BUS_RELATIONS2 =3D PCI_MESSAGE_BASE + 0x19, - PCI_RESOURCES_ASSIGNED3 =3D PCI_MESSAGE_BASE + 0x1A, - PCI_CREATE_INTERRUPT_MESSAGE3 =3D PCI_MESSAGE_BASE + 0x1B, + PCI_RESOURCES_ASSIGNED3 =3D PCI_MESSAGE_BASE + 0x1A, + PCI_CREATE_INTERRUPT_MESSAGE3 =3D PCI_MESSAGE_BASE + 0x1B, PCI_MESSAGE_MAXIMUM }; =20 @@ -1775,20 +1775,21 @@ static u32 hv_compose_msi_req_v1( * via the HVCALL_RETARGET_INTERRUPT hypercall. But the choice of dummy vC= PU is * not irrelevant because Hyper-V chooses the physical CPU to handle the * interrupts based on the vCPU specified in message sent to the vPCI VSP = in - * hv_compose_msi_msg(). Hyper-V's choice of pCPU is not visible to the gu= est, - * but assigning too many vPCI device interrupts to the same pCPU can caus= e a - * performance bottleneck. So we spread out the dummy vCPUs to influence H= yper-V - * to spread out the pCPUs that it selects. + * hv_vmbus_compose_msi_msg(). Hyper-V's choice of pCPU is not visible to = the + * guest, but assigning too many vPCI device interrupts to the same pCPU c= an + * cause a performance bottleneck. So we spread out the dummy vCPUs to inf= luence + * Hyper-V to spread out the pCPUs that it selects. * * For the single-MSI and MSI-X cases, it's OK for hv_compose_msi_req_get_= cpu() * to always return the same dummy vCPU, because a second call to - * hv_compose_msi_msg() contains the "real" vCPU, causing Hyper-V to choos= e a - * new pCPU for the interrupt. But for the multi-MSI case, the second call= to - * hv_compose_msi_msg() exits without sending a message to the vPCI VSP, s= o the - * original dummy vCPU is used. This dummy vCPU must be round-robin'ed so = that - * the pCPUs are spread out. All interrupts for a multi-MSI device end up = using - * the same pCPU, even though the vCPUs will be spread out by later calls - * to hv_irq_unmask(), but that is the best we can do now. + * hv_vmbus_compose_msi_msg() contains the "real" vCPU, causing Hyper-V to + * choose a new pCPU for the interrupt. But for the multi-MSI case, the se= cond + * call to hv_vmbus_compose_msi_msg() exits without sending a message to t= he + * vPCI VSP, so the original dummy vCPU is used. This dummy vCPU must be + * round-robin'ed so that the pCPUs are spread out. All interrupts for a + * multi-MSI device end up using the same pCPU, even though the vCPUs will= be + * spread out by later calls to hv_irq_unmask(), but that is the best we c= an do + * now. * * With Hyper-V in Nov 2022, the HVCALL_RETARGET_INTERRUPT hypercall does = *not* * cause Hyper-V to reselect the pCPU based on the specified vCPU. Such an @@ -1863,7 +1864,7 @@ static u32 hv_compose_msi_req_v3( } =20 /** - * hv_compose_msi_msg() - Supplies a valid MSI address/data + * hv_vmbus_compose_msi_msg() - Supplies a valid MSI address/data * @data: Everything about this MSI * @msg: Buffer that is filled in by this function * @@ -1873,7 +1874,7 @@ static u32 hv_compose_msi_req_v3( * response supplies a data value and address to which that data * should be written to trigger that interrupt. */ -static void hv_compose_msi_msg(struct irq_data *data, struct msi_msg *msg) +static void hv_vmbus_compose_msi_msg(struct irq_data *data, struct msi_msg= *msg) { struct hv_pcibus_device *hbus; struct vmbus_channel *channel; @@ -1955,7 +1956,7 @@ static void hv_compose_msi_msg(struct irq_data *data,= struct msi_msg *msg) return; } /* - * The vector we select here is a dummy value. The correct + * The vector we select here is a dummy value. The correct * value gets sent to the hypervisor in unmask(). This needs * to be aligned with the count, and also not zero. Multi-msi * is powers of 2 up to 32, so 32 will always work here. @@ -2047,7 +2048,7 @@ static void hv_compose_msi_msg(struct irq_data *data,= struct msi_msg *msg) =20 /* * Make sure that the ring buffer data structure doesn't get - * freed while we dereference the ring buffer pointer. Test + * freed while we dereference the ring buffer pointer. Test * for the channel's onchannel_callback being NULL within a * sched_lock critical section. See also the inline comments * in vmbus_reset_channel_cb(). @@ -2147,7 +2148,7 @@ static const struct msi_parent_ops hv_pcie_msi_parent= _ops =3D { /* HW Interrupt Chip Descriptor */ static struct irq_chip hv_msi_irq_chip =3D { .name =3D "Hyper-V PCIe MSI", - .irq_compose_msi_msg =3D hv_compose_msi_msg, + .irq_compose_msi_msg =3D hv_vmbus_compose_msi_msg, .irq_set_affinity =3D irq_chip_set_affinity_parent, .irq_ack =3D irq_chip_ack_parent, .irq_eoi =3D irq_chip_eoi_parent, @@ -2159,8 +2160,8 @@ static int hv_pcie_domain_alloc(struct irq_domain *d,= unsigned int virq, unsigne void *arg) { /* - * TODO: Allocating and populating struct tran_int_desc in hv_compose_msi= _msg() - * should be moved here. + * TODO: Allocating and populating struct tran_int_desc in + * hv_vmbus_compose_msi_msg() should be moved here. */ int ret; =20 @@ -2227,7 +2228,7 @@ static int hv_pcie_init_irq_domain(struct hv_pcibus_d= evice *hbus) /** * get_bar_size() - Get the address space consumed by a BAR * @bar_val: Value that a BAR returned after -1 was written - * to it. + * to it. * * This function returns the size of the BAR, rounded up to 1 * page. It has to be rounded up because the hypervisor's page @@ -2573,7 +2574,7 @@ static void q_resource_requirements(void *context, st= ruct pci_response *resp, * new_pcichild_device() - Create a new child device * @hbus: The internal struct tracking this root PCI bus. * @desc: The information supplied so far from the host - * about the device. + * about the device. * * This function creates the tracking structure for a new child * device and kicks off the process of figuring out what it is. @@ -3100,7 +3101,7 @@ static void hv_pci_onchannelcallback(void *context) * sure that the packet pointer is still valid during the call: * here 'valid' means that there's a task still waiting for the * completion, and that the packet data is still on the waiting - * task's stack. Cf. hv_compose_msi_msg(). + * task's stack. Cf. hv_vmbus_compose_msi_msg(). */ comp_packet->completion_func(comp_packet->compl_ctxt, response, @@ -3417,7 +3418,7 @@ static int hv_allocate_config_window(struct hv_pcibus= _device *hbus) * vmbus_allocate_mmio() gets used for allocating both device endpoint * resource claims (those which cannot be overlapped) and the ranges * which are valid for the children of this bus, which are intended - * to be overlapped by those children. Set the flag on this claim + * to be overlapped by those children. Set the flag on this claim * meaning that this region can't be overlapped. */ =20 @@ -4066,7 +4067,7 @@ static int hv_pci_restore_msi_msg(struct pci_dev *pde= v, void *arg) irq_data =3D irq_get_irq_data(entry->irq); if (WARN_ON_ONCE(!irq_data)) return -EINVAL; - hv_compose_msi_msg(irq_data, &entry->msg); + hv_vmbus_compose_msi_msg(irq_data, &entry->msg); } return 0; } @@ -4074,7 +4075,7 @@ static int hv_pci_restore_msi_msg(struct pci_dev *pde= v, void *arg) /* * Upon resume, pci_restore_msi_state() -> ... -> __pci_write_msi_msg() * directly writes the MSI/MSI-X registers via MMIO, but since Hyper-V - * doesn't trap and emulate the MMIO accesses, here hv_compose_msi_msg() + * doesn't trap and emulate the MMIO accesses, here hv_vmbus_compose_msi_m= sg() * must be used to ask Hyper-V to re-create the IOMMU Interrupt Remapping * Table entries. */ --=20 2.51.2.vfs.0.1 From nobody Sat Feb 7 15:15:18 2026 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 7E4D839341D; Tue, 20 Jan 2026 06:43:46 +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=1768891438; cv=none; b=adQswXj9kzj4Gy1x1SEKuSyN0peDP2W/Im6OkVO73pUq5vkbJGVUDR4OQr+1m8Y4I8WcaPkdySqr11zT5Kd1eVM9b/dDJp7xMweaUe2u8YPV1KKCVzH99ns098/CZMzTdWWQtlMTu0L4GM7lS1Nv3ZUlQPN8vyaXqGyYrK71dMc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768891438; c=relaxed/simple; bh=t6KWa8Ywuv55mBlGRMItarSrgfml7ndi5kM3By2DgKQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Qeb5VKEkWUEbbSg0FuE4UAEFZO1eTMqLyDLq13l+8eRF2WRFzBENzLswOjPO3+KN1BA6yYvPJ/L0XdKvCx8ted9CsJRPGLqv+N3DhBLla1oC32tOetphc4NbXTBLypy1vItU6VvFM5p2aOeGUp9xvY+poucQxGrEOUZ5byDctSk= 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=mdo0t083; 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="mdo0t083" Received: from mrdev.corp.microsoft.com (192-184-212-33.fiber.dynamic.sonic.net [192.184.212.33]) by linux.microsoft.com (Postfix) with ESMTPSA id 9907E20B7172; Mon, 19 Jan 2026 22:43:37 -0800 (PST) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 9907E20B7172 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1768891418; bh=wqmyheb8rD2njJBWwC6GothbZYR9ohwQrRX05s9s+ww=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=mdo0t0832V1O+P0nkREY95p7rRr4BZA+JyroNqivGh/7D1MngHH8XQJkpu98A9Foh sOdWA6RVvsvFJst/F2Qz5wNtwXWijEPiDguG0XLtCIE+iAJVeRyD8L9S35pRYClIAm ZSYLlmlmQgZZ6k9YxVuH6tdQjnmLOKCDy/BVySGU= From: Mukesh R To: linux-kernel@vger.kernel.org, linux-hyperv@vger.kernel.org, linux-arm-kernel@lists.infradead.org, iommu@lists.linux.dev, linux-pci@vger.kernel.org, linux-arch@vger.kernel.org Cc: kys@microsoft.com, haiyangz@microsoft.com, wei.liu@kernel.org, decui@microsoft.com, longli@microsoft.com, catalin.marinas@arm.com, will@kernel.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com, joro@8bytes.org, lpieralisi@kernel.org, kwilczynski@kernel.org, mani@kernel.org, robh@kernel.org, bhelgaas@google.com, arnd@arndb.de, nunodasneves@linux.microsoft.com, mhklinux@outlook.com, romank@linux.microsoft.com Subject: [PATCH v0 09/15] mshv: Import data structs around device domains and irq remapping Date: Mon, 19 Jan 2026 22:42:24 -0800 Message-ID: <20260120064230.3602565-10-mrathor@linux.microsoft.com> X-Mailer: git-send-email 2.51.2.vfs.0.1 In-Reply-To: <20260120064230.3602565-1-mrathor@linux.microsoft.com> References: <20260120064230.3602565-1-mrathor@linux.microsoft.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Mukesh Rathor Import/copy from Hyper-V public headers, definitions and declarations that are related to attaching and detaching of device domains and interrupt remapping, and building device ids for those purposes. Signed-off-by: Mukesh Rathor --- include/hyperv/hvgdk_mini.h | 11 ++++ include/hyperv/hvhdk_mini.h | 112 ++++++++++++++++++++++++++++++++++++ 2 files changed, 123 insertions(+) diff --git a/include/hyperv/hvgdk_mini.h b/include/hyperv/hvgdk_mini.h index 04b18d0e37af..bda9fae5b1ef 100644 --- a/include/hyperv/hvgdk_mini.h +++ b/include/hyperv/hvgdk_mini.h @@ -323,6 +323,9 @@ union hv_hypervisor_version_info { /* stimer Direct Mode is available */ #define HV_STIMER_DIRECT_MODE_AVAILABLE BIT(19) =20 +#define HV_DEVICE_DOMAIN_AVAILABLE BIT(24) +#define HV_S1_DEVICE_DOMAIN_AVAILABLE BIT(25) + /* * Implementation recommendations. Indicates which behaviors the hypervisor * recommends the OS implement for optimal performance. @@ -471,6 +474,8 @@ union hv_vp_assist_msr_contents { /* HV_REGISTER_VP_AS= SIST_PAGE */ #define HVCALL_MAP_DEVICE_INTERRUPT 0x007c #define HVCALL_UNMAP_DEVICE_INTERRUPT 0x007d #define HVCALL_RETARGET_INTERRUPT 0x007e +#define HVCALL_ATTACH_DEVICE 0x0082 +#define HVCALL_DETACH_DEVICE 0x0083 #define HVCALL_NOTIFY_PARTITION_EVENT 0x0087 #define HVCALL_ENTER_SLEEP_STATE 0x0084 #define HVCALL_NOTIFY_PORT_RING_EMPTY 0x008b @@ -482,9 +487,15 @@ union hv_vp_assist_msr_contents { /* HV_REGISTER_VP_A= SSIST_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_MAP_DEVICE_GPA_PAGES 0x00b3 +#define HVCALL_UNMAP_DEVICE_GPA_PAGES 0x00b4 #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_ACQUIRE_SPARSE_SPA_PAGE_HOST_ACCESS 0x00d7 #define HVCALL_RELEASE_SPARSE_SPA_PAGE_HOST_ACCESS 0x00d8 diff --git a/include/hyperv/hvhdk_mini.h b/include/hyperv/hvhdk_mini.h index 41a29bf8ec14..57821d6ddb61 100644 --- a/include/hyperv/hvhdk_mini.h +++ b/include/hyperv/hvhdk_mini.h @@ -449,6 +449,32 @@ struct hv_send_ipi_ex { /* HV_INPUT_SEND_SYNTHETIC_CLU= STER_IPI_EX */ struct hv_vpset vp_set; } __packed; =20 +union hv_attdev_flags { /* HV_ATTACH_DEVICE_FLAGS */ + struct { + u32 logical_id : 1; + u32 resvd0 : 1; + u32 ats_enabled : 1; + u32 virt_func : 1; + u32 shared_irq_child : 1; + u32 virt_dev : 1; + u32 ats_supported : 1; + u32 small_irt : 1; + u32 resvd : 24; + } __packed; + u32 as_uint32; +}; + +union hv_dev_pci_caps { /* HV_DEVICE_PCI_CAPABILITIES */ + struct { + u32 max_pasid_width : 5; + u32 invalidate_qdepth : 5; + u32 global_inval : 1; + u32 prg_response_req : 1; + u32 resvd : 20; + } __packed; + u32 as_uint32; +}; + typedef u16 hv_pci_rid; /* HV_PCI_RID */ typedef u16 hv_pci_segment; /* HV_PCI_SEGMENT */ typedef u64 hv_logical_device_id; @@ -528,4 +554,90 @@ union hv_device_id { /* HV_DEVICE_ID */ } acpi; } __packed; =20 +struct hv_input_attach_device { /* HV_INPUT_ATTACH_DEVICE */ + u64 partition_id; + union hv_device_id device_id; + union hv_attdev_flags attdev_flags; + u8 attdev_vtl; + u8 rsvd0; + u16 rsvd1; + u64 logical_devid; + union hv_dev_pci_caps dev_pcicaps; + u16 pf_pci_rid; + u16 resvd2; +} __packed; + +struct hv_input_detach_device { /* HV_INPUT_DETACH_DEVICE */ + u64 partition_id; + u64 logical_devid; +} __packed; + + +/* 3 domain types: stage 1, stage 2, and SOC */ +#define HV_DEVICE_DOMAIN_TYPE_S2 0 /* HV_DEVICE_DOMAIN_ID_TYPE_S2 */ +#define HV_DEVICE_DOMAIN_TYPE_S1 1 /* HV_DEVICE_DOMAIN_ID_TYPE_S1 */ +#define HV_DEVICE_DOMAIN_TYPE_SOC 2 /* HV_DEVICE_DOMAIN_ID_TYPE_SOC */ + +/* ID for stage 2 default domain and NULL domain */ +#define HV_DEVICE_DOMAIN_ID_S2_DEFAULT 0 +#define HV_DEVICE_DOMAIN_ID_S2_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 { /* 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 { /* HV_CREATE_DEVICE_DOMAIN_FLAGS */ + u32 as_uint32; + struct { + u32 forward_progress_required : 1; + u32 inherit_owning_vtl : 1; + u32 reserved : 30; + } __packed; +} __packed; + +struct hv_input_create_device_domain { /* 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 { /* HV_INPUT_DELETE_DEVICE_DOMAIN */ + struct hv_input_device_domain device_domain; +} __packed; + +struct hv_input_attach_device_domain { /* 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 { /* HV_INPUT_DETACH_DEVICE_DOMAIN */ + u64 partition_id; + union hv_device_id device_id; +} __packed; + +struct hv_input_map_device_gpa_pages { /* HV_INPUT_MAP_DEVICE_GPA_PAGES */ + struct hv_input_device_domain device_domain; + union hv_input_vtl target_vtl; + u8 padding[3]; + u32 map_flags; + u64 target_device_va_base; + u64 gpa_page_list[]; +} __packed; + +struct hv_input_unmap_device_gpa_pages { /* HV_INPUT_UNMAP_DEVICE_GPA_PAG= ES */ + struct hv_input_device_domain device_domain; + u64 target_device_va_base; +} __packed; + #endif /* _HV_HVHDK_MINI_H */ --=20 2.51.2.vfs.0.1 From nobody Sat Feb 7 15:15:18 2026 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 1F61537F8C9; Tue, 20 Jan 2026 06:43:46 +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=1768891440; cv=none; b=oPBFcWcYG6EZ4RN0rHxiVWtfBD/s3qh9hlyf1KPpHnOvHILHe4bSWtBTfd39hMuZDU3AEKOCSdxM99XxX/GM45MPDv/uYMN+UobP+eN1iA3VCeOt4uX1I0xwasOvnKoPyl1B/yGCww7K4VLXQHxPa3WXXB+quqVX/v+9T6DlT+s= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768891440; c=relaxed/simple; bh=BalUxhQJ1yFzwpzZ+AK8cf6+vgLeWHhnt34Pqi87B4Y=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=PtzpUtwrtVXhPk+6Ep0cKlFtnbvU8JSPiDNfoN4Lf5YZc7JfGQgQBt34RZREeKPEd1pCmO+2zqJ3KDK1OQI1+O1LyBYfmUDJNqRgbZ8VISOoJiDkvPZJC9MMXx3KH/nG1WGKjc0ME6+eGqdAuKlw3tlcuvZmMFuMhvxV2e90ZwQ= 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=bWnfQDL5; 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="bWnfQDL5" Received: from mrdev.corp.microsoft.com (192-184-212-33.fiber.dynamic.sonic.net [192.184.212.33]) by linux.microsoft.com (Postfix) with ESMTPSA id C8E3D20B7167; Mon, 19 Jan 2026 22:43:38 -0800 (PST) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com C8E3D20B7167 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1768891419; bh=+gfNKWeY08Vm8PNbCFC1rEYtYrIGwfSMI5VrEew50HM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=bWnfQDL5EUpEsU3VzMRuWBTbnZ3bATyez623M6D62i2f141uJAJGhHGyGTh+MdAt1 YP6Tq7BIRfj0D3JdRcLqQw3mfIdiF6PR0FqAQxPP+4n82vypfpQBll8q63FbRw9W+p wxIBkhEnSWn9JFFv8q8IWYkupEoY/QP4lQqvHtzE= From: Mukesh R To: linux-kernel@vger.kernel.org, linux-hyperv@vger.kernel.org, linux-arm-kernel@lists.infradead.org, iommu@lists.linux.dev, linux-pci@vger.kernel.org, linux-arch@vger.kernel.org Cc: kys@microsoft.com, haiyangz@microsoft.com, wei.liu@kernel.org, decui@microsoft.com, longli@microsoft.com, catalin.marinas@arm.com, will@kernel.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com, joro@8bytes.org, lpieralisi@kernel.org, kwilczynski@kernel.org, mani@kernel.org, robh@kernel.org, bhelgaas@google.com, arnd@arndb.de, nunodasneves@linux.microsoft.com, mhklinux@outlook.com, romank@linux.microsoft.com Subject: [PATCH v0 10/15] PCI: hv: Build device id for a VMBus device Date: Mon, 19 Jan 2026 22:42:25 -0800 Message-ID: <20260120064230.3602565-11-mrathor@linux.microsoft.com> X-Mailer: git-send-email 2.51.2.vfs.0.1 In-Reply-To: <20260120064230.3602565-1-mrathor@linux.microsoft.com> References: <20260120064230.3602565-1-mrathor@linux.microsoft.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Mukesh Rathor On Hyper-V, most hypercalls related to PCI passthru to map/unmap regions, interrupts, etc need a device id as a parameter. This device id refers to that specific device during the lifetime of passthru. An L1VH VM only contains VMBus based devices. A device id for a VMBus device is slightly different in that it uses the hv_pcibus_device info for building it to make sure it matches exactly what the hypervisor expects. This VMBus based device id is needed when attaching devices in an L1VH based guest VM. Before building it, a check is done to make sure the device is a valid VMBus device. Signed-off-by: Mukesh Rathor --- arch/x86/include/asm/mshyperv.h | 2 ++ drivers/pci/controller/pci-hyperv.c | 29 +++++++++++++++++++++++++++++ 2 files changed, 31 insertions(+) diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyper= v.h index eef4c3a5ba28..0d7fdfb25e76 100644 --- a/arch/x86/include/asm/mshyperv.h +++ b/arch/x86/include/asm/mshyperv.h @@ -188,6 +188,8 @@ bool hv_vcpu_is_preempted(int vcpu); static inline void hv_apic_init(void) {} #endif =20 +u64 hv_pci_vmbus_device_id(struct pci_dev *pdev); + struct irq_domain *hv_create_pci_msi_domain(void); =20 int hv_map_msi_interrupt(struct irq_data *data, diff --git a/drivers/pci/controller/pci-hyperv.c b/drivers/pci/controller/p= ci-hyperv.c index 8bc6a38c9b5a..40f0b06bb966 100644 --- a/drivers/pci/controller/pci-hyperv.c +++ b/drivers/pci/controller/pci-hyperv.c @@ -579,6 +579,8 @@ static void hv_pci_onchannelcallback(void *context); #define DELIVERY_MODE APIC_DELIVERY_MODE_FIXED #define HV_MSI_CHIP_FLAGS MSI_CHIP_FLAG_SET_ACK =20 +static bool hv_vmbus_pci_device(struct pci_bus *pbus); + static int hv_pci_irqchip_init(void) { return 0; @@ -598,6 +600,26 @@ static unsigned int hv_msi_get_int_vector(struct irq_d= ata *data) =20 #define hv_msi_prepare pci_msi_prepare =20 +u64 hv_pci_vmbus_device_id(struct pci_dev *pdev) +{ + u64 u64val; + struct hv_pcibus_device *hbus; + struct pci_bus *pbus =3D pdev->bus; + + if (!hv_vmbus_pci_device(pbus)) + return 0; + + hbus =3D container_of(pbus->sysdata, struct hv_pcibus_device, sysdata); + u64val =3D (hbus->hdev->dev_instance.b[5] << 24) | + (hbus->hdev->dev_instance.b[4] << 16) | + (hbus->hdev->dev_instance.b[7] << 8) | + (hbus->hdev->dev_instance.b[6] & 0xf8) | + PCI_FUNC(pdev->devfn); + + return u64val; +} +EXPORT_SYMBOL_GPL(hv_pci_vmbus_device_id); + /** * hv_irq_retarget_interrupt() - "Unmask" the IRQ by setting its current * affinity. @@ -1404,6 +1426,13 @@ static struct pci_ops hv_pcifront_ops =3D { .write =3D hv_pcifront_write_config, }; =20 +#ifdef CONFIG_X86 +static bool hv_vmbus_pci_device(struct pci_bus *pbus) +{ + return pbus->ops =3D=3D &hv_pcifront_ops; +} +#endif /* CONFIG_X86 */ + /* * Paravirtual backchannel * --=20 2.51.2.vfs.0.1 From nobody Sat Feb 7 15:15:18 2026 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 8B42D374185; Tue, 20 Jan 2026 06:43:48 +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=1768891440; cv=none; b=gGPDfukSk3qoWGYoV8hlSXt2ZuTo0BXn6vnCw0FpyDAqkSuRxYK/tw2oIbI3/5ZHZSFfVzg7JkrO3vMf3vncv4+lY57HLN9aTDmZ11ImwSIJHHXp4sOS1RlBbr9Iv1orNEPs5km1Hy03vzXlScBUO20/CSlE//k7q7ArtM89gjA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768891440; c=relaxed/simple; bh=FiWfyrWbpLORzTtg0lzCDru3O9TKF1o+yJ40EJBTcnU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=VqWS87UOq9eA59zW1H/OCKddtcpd3UiGrYGapfzmp6J5IEXAQTp0Q8FC2bb65HNFrMIL1EXMs7A3SbOD7fPsbYjDi4L0GEo3MhEXa4xKS+LiMmBxMEF5bTiuTxg5Sxlfwf/49u0hDKj87SZGbU60iU4+LxXI0q/5Dv4+u/TB9Zw= ARC-Authentication-Results: i=1; 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bh=e5zTidzD1l2EkEPlrmawzN2dIfFYQQCNH1hdqUaixrE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=UNMpFJkAxc0ipZ/uc95ODahk07NK6NWJyqWcGkaZVKyIZt1UDQiiBulzjGwCk91VX jt0oLrxXe6iYTsRwRbf+EqSpgCO1gfUoGkAjX1AJ38Zyc7EB7vv0f3UcxIZZ6sNoFr vdmcs3Bq/RId5HwNs85PYXjzf1VCUY/upizMZ+/c= From: Mukesh R To: linux-kernel@vger.kernel.org, linux-hyperv@vger.kernel.org, linux-arm-kernel@lists.infradead.org, iommu@lists.linux.dev, linux-pci@vger.kernel.org, linux-arch@vger.kernel.org Cc: kys@microsoft.com, haiyangz@microsoft.com, wei.liu@kernel.org, decui@microsoft.com, longli@microsoft.com, catalin.marinas@arm.com, will@kernel.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com, joro@8bytes.org, lpieralisi@kernel.org, kwilczynski@kernel.org, mani@kernel.org, robh@kernel.org, bhelgaas@google.com, arnd@arndb.de, nunodasneves@linux.microsoft.com, mhklinux@outlook.com, romank@linux.microsoft.com Subject: [PATCH v0 11/15] x86/hyperv: Build logical device ids for PCI passthru hcalls Date: Mon, 19 Jan 2026 22:42:26 -0800 Message-ID: <20260120064230.3602565-12-mrathor@linux.microsoft.com> X-Mailer: git-send-email 2.51.2.vfs.0.1 In-Reply-To: <20260120064230.3602565-1-mrathor@linux.microsoft.com> References: <20260120064230.3602565-1-mrathor@linux.microsoft.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Mukesh Rathor On Hyper-V, most hypercalls related to PCI passthru to map/unmap regions, interrupts, etc need a device id as a parameter. A device id refers to a specific device. A device id is of two types: o Logical: used for direct attach (see below) hypercalls. A logical device id is a unique 62bit value that is created and sent during the initial device attach. Then all further communications (for interrupt remaps etc) must use this logical id. o PCI: used for device domain hypercalls such as map, unmap, etc. This is built using actual device BDF info. PS: Since an L1VH only supports direct attaches, a logical device id on an L1VH VM is always a VMBus device id. For non-L1VH cases, we just use PCI BDF info, altho not strictly needed, to build the logical device id. At a high level, Hyper-V supports two ways to do PCI passthru: 1. Device Domain: root must create a device domain in the hypervisor, and do map/unmap hypercalls for mapping and unmapping guest RAM. All hypervisor communications use device id of type PCI for identifying and referencing the device. 2. Direct Attach: the hypervisor will simply use the guest's HW page table for mappings, thus the host need not do map/unmap hypercalls. A direct attached device must be referenced via logical device id and never via the PCI device id. For an L1VH root/parent, Hyper-V only supports direct attaches. Signed-off-by: Mukesh Rathor --- arch/x86/hyperv/irqdomain.c | 60 ++++++++++++++++++++++++++++++--- arch/x86/include/asm/mshyperv.h | 14 ++++++++ 2 files changed, 70 insertions(+), 4 deletions(-) diff --git a/arch/x86/hyperv/irqdomain.c b/arch/x86/hyperv/irqdomain.c index ccbe5848a28f..33017aa0caa4 100644 --- a/arch/x86/hyperv/irqdomain.c +++ b/arch/x86/hyperv/irqdomain.c @@ -137,7 +137,7 @@ static int get_rid_cb(struct pci_dev *pdev, u16 alias, = void *data) return 0; } =20 -static union hv_device_id hv_build_devid_type_pci(struct pci_dev *pdev) +static u64 hv_build_devid_type_pci(struct pci_dev *pdev) { int pos; union hv_device_id hv_devid; @@ -197,7 +197,58 @@ static union hv_device_id hv_build_devid_type_pci(stru= ct pci_dev *pdev) } =20 out: - return hv_devid; + return hv_devid.as_uint64; +} + +/* Build device id for direct attached devices */ +static u64 hv_build_devid_type_logical(struct pci_dev *pdev) +{ + hv_pci_segment segment; + union hv_device_id hv_devid; + union hv_pci_bdf bdf =3D {.as_uint16 =3D 0}; + struct rid_data data =3D { + .bridge =3D NULL, + .rid =3D PCI_DEVID(pdev->bus->number, pdev->devfn) + }; + + segment =3D pci_domain_nr(pdev->bus); + bdf.bus =3D PCI_BUS_NUM(data.rid); + bdf.device =3D PCI_SLOT(data.rid); + bdf.function =3D PCI_FUNC(data.rid); + + hv_devid.as_uint64 =3D 0; + hv_devid.device_type =3D HV_DEVICE_TYPE_LOGICAL; + hv_devid.logical.id =3D (u64)segment << 16 | bdf.as_uint16; + + return hv_devid.as_uint64; +} + +/* Build device id after the device has been attached */ +u64 hv_build_devid_oftype(struct pci_dev *pdev, enum hv_device_type type) +{ + if (type =3D=3D HV_DEVICE_TYPE_LOGICAL) { + if (hv_l1vh_partition()) + return hv_pci_vmbus_device_id(pdev); + else + return hv_build_devid_type_logical(pdev); + } else if (type =3D=3D HV_DEVICE_TYPE_PCI) + return hv_build_devid_type_pci(pdev); + + return 0; +} +EXPORT_SYMBOL_GPL(hv_build_devid_oftype); + +/* Build device id for the interrupt path */ +static u64 hv_build_irq_devid(struct pci_dev *pdev) +{ + enum hv_device_type dev_type; + + if (hv_pcidev_is_attached_dev(pdev) || hv_l1vh_partition()) + dev_type =3D HV_DEVICE_TYPE_LOGICAL; + else + dev_type =3D HV_DEVICE_TYPE_PCI; + + return hv_build_devid_oftype(pdev, dev_type); } =20 /* @@ -221,7 +272,7 @@ int hv_map_msi_interrupt(struct irq_data *data, =20 msidesc =3D irq_data_get_msi_desc(data); pdev =3D msi_desc_to_pci_dev(msidesc); - hv_devid =3D hv_build_devid_type_pci(pdev); + hv_devid.as_uint64 =3D hv_build_irq_devid(pdev); cpu =3D cpumask_first(irq_data_get_effective_affinity_mask(data)); =20 return hv_map_interrupt(hv_current_partition_id, hv_devid, false, cpu, @@ -296,7 +347,8 @@ static int hv_unmap_msi_interrupt(struct pci_dev *pdev, { union hv_device_id hv_devid; =20 - hv_devid =3D hv_build_devid_type_pci(pdev); + hv_devid.as_uint64 =3D hv_build_irq_devid(pdev); + return hv_unmap_interrupt(hv_devid.as_uint64, irq_entry); } =20 diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyper= v.h index 0d7fdfb25e76..97477c5a8487 100644 --- a/arch/x86/include/asm/mshyperv.h +++ b/arch/x86/include/asm/mshyperv.h @@ -188,6 +188,20 @@ bool hv_vcpu_is_preempted(int vcpu); static inline void hv_apic_init(void) {} #endif =20 +#if IS_ENABLED(CONFIG_HYPERV_IOMMU) +static inline bool hv_pcidev_is_attached_dev(struct pci_dev *pdev) +{ return false; } /* temporary */ +u64 hv_build_devid_oftype(struct pci_dev *pdev, enum hv_device_type type); +#else /* CONFIG_HYPERV_IOMMU */ +static inline bool hv_pcidev_is_attached_dev(struct pci_dev *pdev) +{ return false; } + +static inline u64 hv_build_devid_oftype(struct pci_dev *pdev, + enum hv_device_type type) +{ return 0; } + +#endif /* CONFIG_HYPERV_IOMMU */ + u64 hv_pci_vmbus_device_id(struct pci_dev *pdev); =20 struct irq_domain *hv_create_pci_msi_domain(void); --=20 2.51.2.vfs.0.1 From nobody Sat Feb 7 15:15:18 2026 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 1A6A238E5CC; Tue, 20 Jan 2026 06:43:49 +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; 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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="WlEk+tNC" Received: from mrdev.corp.microsoft.com (192-184-212-33.fiber.dynamic.sonic.net [192.184.212.33]) by linux.microsoft.com (Postfix) with ESMTPSA id B514820B716B; Mon, 19 Jan 2026 22:43:45 -0800 (PST) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com B514820B716B DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1768891426; bh=LALVYDoDS9Z7foVmNCACVg/mKXscj2r1Oweg1CvTLTs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=WlEk+tNC2kjElZfsfFls162d6n9mkQ1TwXBVjgIsKiP5hv8/5hMcAlQy6RRd6h6Rd pcL0I2/FZ9Y53OeKUB5pkSg8raA+UqyeoXD5T2bId3m3JsGtpn/gnYv/Av0OE6CTGf zJwVVjmWKlPMxHikKBsumMs92svA6FYh5bmUNIyU= From: Mukesh R To: linux-kernel@vger.kernel.org, linux-hyperv@vger.kernel.org, linux-arm-kernel@lists.infradead.org, iommu@lists.linux.dev, linux-pci@vger.kernel.org, linux-arch@vger.kernel.org Cc: kys@microsoft.com, haiyangz@microsoft.com, wei.liu@kernel.org, decui@microsoft.com, longli@microsoft.com, catalin.marinas@arm.com, will@kernel.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com, joro@8bytes.org, lpieralisi@kernel.org, kwilczynski@kernel.org, mani@kernel.org, robh@kernel.org, bhelgaas@google.com, arnd@arndb.de, nunodasneves@linux.microsoft.com, mhklinux@outlook.com, romank@linux.microsoft.com Subject: [PATCH v0 12/15] x86/hyperv: Implement hyperv virtual iommu Date: Mon, 19 Jan 2026 22:42:27 -0800 Message-ID: <20260120064230.3602565-13-mrathor@linux.microsoft.com> X-Mailer: git-send-email 2.51.2.vfs.0.1 In-Reply-To: <20260120064230.3602565-1-mrathor@linux.microsoft.com> References: <20260120064230.3602565-1-mrathor@linux.microsoft.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Mukesh Rathor Add a new file to implement management of device domains, mapping and unmapping of iommu memory, and other iommu_ops to fit within the VFIO framework for PCI passthru on Hyper-V running Linux as root or L1VH parent. This also implements direct attach mechanism for PCI passthru, and it is also made to work within the VFIO framework. At a high level, during boot the hypervisor creates a default identity domain and attaches all devices to it. This nicely maps to Linux iommu subsystem IOMMU_DOMAIN_IDENTITY domain. As a result, Linux does not need to explicitly ask Hyper-V to attach devices and do maps/unmaps during boot. As mentioned previously, Hyper-V supports two ways to do PCI passthru: 1. Device Domain: root must create a device domain in the hypervisor, and do map/unmap hypercalls for mapping and unmapping guest RAM. All hypervisor communications use device id of type PCI for identifying and referencing the device. 2. Direct Attach: the hypervisor will simply use the guest's HW page table for mappings, thus the host need not do map/unmap device memory hypercalls. As such, direct attach passthru setup during guest boot is extremely fast. A direct attached device must be referenced via logical device id and not via the PCI device id. At present, L1VH root/parent only supports direct attaches. Also direct attach is default in non-L1VH cases because there are some significant performance issues with device domain implementation currently for guests with higher RAM (say more than 8GB), and that unfortunately cannot be addressed in the short term. Signed-off-by: Mukesh Rathor --- MAINTAINERS | 1 + arch/x86/include/asm/mshyperv.h | 7 +- arch/x86/kernel/pci-dma.c | 2 + drivers/iommu/Makefile | 2 +- drivers/iommu/hyperv-iommu.c | 876 ++++++++++++++++++++++++++++++++ include/linux/hyperv.h | 6 + 6 files changed, 890 insertions(+), 4 deletions(-) create mode 100644 drivers/iommu/hyperv-iommu.c diff --git a/MAINTAINERS b/MAINTAINERS index 381a0e086382..63160cee942c 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -11741,6 +11741,7 @@ F: drivers/hid/hid-hyperv.c F: drivers/hv/ F: drivers/infiniband/hw/mana/ F: drivers/input/serio/hyperv-keyboard.c +F: drivers/iommu/hyperv-iommu.c F: drivers/iommu/hyperv-irq.c F: drivers/net/ethernet/microsoft/ F: drivers/net/hyperv/ diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyper= v.h index 97477c5a8487..e4ccdbbf1d12 100644 --- a/arch/x86/include/asm/mshyperv.h +++ b/arch/x86/include/asm/mshyperv.h @@ -189,16 +189,17 @@ static inline void hv_apic_init(void) {} #endif =20 #if IS_ENABLED(CONFIG_HYPERV_IOMMU) -static inline bool hv_pcidev_is_attached_dev(struct pci_dev *pdev) -{ return false; } /* temporary */ +bool hv_pcidev_is_attached_dev(struct pci_dev *pdev); u64 hv_build_devid_oftype(struct pci_dev *pdev, enum hv_device_type type); +u64 hv_iommu_get_curr_partid(void); #else /* CONFIG_HYPERV_IOMMU */ static inline bool hv_pcidev_is_attached_dev(struct pci_dev *pdev) { return false; } - static inline u64 hv_build_devid_oftype(struct pci_dev *pdev, enum hv_device_type type) { return 0; } +static inline u64 hv_iommu_get_curr_partid(void) +{ return HV_PARTITION_ID_INVALID; } =20 #endif /* CONFIG_HYPERV_IOMMU */ =20 diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c index 6267363e0189..cfeee6505e17 100644 --- a/arch/x86/kernel/pci-dma.c +++ b/arch/x86/kernel/pci-dma.c @@ -8,6 +8,7 @@ #include #include #include +#include =20 #include #include @@ -105,6 +106,7 @@ void __init pci_iommu_alloc(void) gart_iommu_hole_init(); amd_iommu_detect(); detect_intel_iommu(); + hv_iommu_detect(); swiotlb_init(x86_swiotlb_enable, x86_swiotlb_flags); } =20 diff --git a/drivers/iommu/Makefile b/drivers/iommu/Makefile index 598c39558e7d..cc9774864b00 100644 --- a/drivers/iommu/Makefile +++ b/drivers/iommu/Makefile @@ -30,7 +30,7 @@ obj-$(CONFIG_TEGRA_IOMMU_SMMU) +=3D tegra-smmu.o obj-$(CONFIG_EXYNOS_IOMMU) +=3D exynos-iommu.o obj-$(CONFIG_FSL_PAMU) +=3D fsl_pamu.o fsl_pamu_domain.o obj-$(CONFIG_S390_IOMMU) +=3D s390-iommu.o -obj-$(CONFIG_HYPERV_IOMMU) +=3D hyperv-irq.o +obj-$(CONFIG_HYPERV_IOMMU) +=3D hyperv-irq.o hyperv-iommu.o obj-$(CONFIG_VIRTIO_IOMMU) +=3D virtio-iommu.o obj-$(CONFIG_IOMMU_SVA) +=3D iommu-sva.o obj-$(CONFIG_IOMMU_IOPF) +=3D io-pgfault.o diff --git a/drivers/iommu/hyperv-iommu.c b/drivers/iommu/hyperv-iommu.c new file mode 100644 index 000000000000..548483fec6b1 --- /dev/null +++ b/drivers/iommu/hyperv-iommu.c @@ -0,0 +1,876 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Hyper-V root vIOMMU driver. + * Copyright (C) 2026, Microsoft, Inc. + */ + +#include +#include +#include +#include +#include +#include +#include "dma-iommu.h" +#include +#include + +/* We will not claim these PCI devices, eg hypervisor needs it for debugge= r */ +static char *pci_devs_to_skip; +static int __init hv_iommu_setup_skip(char *str) +{ + pci_devs_to_skip =3D str; + + return 0; +} +/* hv_iommu_skip=3D(SSSS:BB:DD.F)(SSSS:BB:DD.F) */ +__setup("hv_iommu_skip=3D", hv_iommu_setup_skip); + +bool hv_no_attdev; /* disable direct device attach for passthru */ +EXPORT_SYMBOL_GPL(hv_no_attdev); +static int __init setup_hv_no_attdev(char *str) +{ + hv_no_attdev =3D true; + return 0; +} +__setup("hv_no_attdev", setup_hv_no_attdev); + +/* Iommu device that we export to the world. HyperV supports max of one */ +static struct iommu_device hv_virt_iommu; + +struct hv_domain { + struct iommu_domain iommu_dom; + u32 domid_num; /* as opposed to domain_id.type */ + u32 num_attchd; /* number of currently attached devices */ + bool attached_dom; /* is this direct attached dom? */ + spinlock_t mappings_lock; /* protects mappings_tree */ + struct rb_root_cached mappings_tree; /* iova to pa lookup tree */ +}; + +#define to_hv_domain(d) container_of(d, struct hv_domain, iommu_dom) + +struct hv_iommu_mapping { + phys_addr_t paddr; + struct interval_tree_node iova; + u32 flags; +}; + +/* + * By default, during boot the hypervisor creates one Stage 2 (S2) default + * domain. Stage 2 means that the page table is controlled by the hypervis= or. + * S2 default: access to entire root partition memory. This for us easily + * maps to IOMMU_DOMAIN_IDENTITY in the iommu subsystem, and + * is called HV_DEVICE_DOMAIN_ID_S2_DEFAULT in the hypervisor. + * + * Device Management: + * There are two ways to manage device attaches to domains: + * 1. Domain Attach: A device domain is created in the hypervisor, the + * device is attached to this domain, and then memory + * ranges are mapped in the map callbacks. + * 2. Direct Attach: No need to create a domain in the hypervisor for = direct + * attached devices. A hypercall is made to tell the + * hypervisor to attach the device to a guest. There is + * no need for explicit memory mappings because the + * hypervisor will just use the guest HW page table. + * + * Since a direct attach is much faster, it is the default. This can be + * changed via hv_no_attdev. + * + * L1VH: hypervisor only supports direct attach. + */ + +/* + * Create dummy domain to correspond to hypervisor prebuilt default identi= ty + * domain (dummy because we do not make hypercall to create them). + */ +static struct hv_domain hv_def_identity_dom; + +static bool hv_special_domain(struct hv_domain *hvdom) +{ + return hvdom =3D=3D &hv_def_identity_dom; +} + +struct iommu_domain_geometry default_geometry =3D (struct iommu_domain_geo= metry) { + .aperture_start =3D 0, + .aperture_end =3D -1UL, + .force_aperture =3D true, +}; + +/* + * Since the relevant hypercalls can only fit less than 512 PFNs in the pfn + * array, report 1M max. + */ +#define HV_IOMMU_PGSIZES (SZ_4K | SZ_1M) + +static u32 unique_id; /* unique numeric id of a new domain */ + +static void hv_iommu_detach_dev(struct iommu_domain *immdom, + struct device *dev); +static size_t hv_iommu_unmap_pages(struct iommu_domain *immdom, ulong iova, + size_t pgsize, size_t pgcount, + struct iommu_iotlb_gather *gather); + +/* + * If the current thread is a VMM thread, return the partition id of the V= M it + * is managing, else return HV_PARTITION_ID_INVALID. + */ +u64 hv_iommu_get_curr_partid(void) +{ + u64 (*fn)(pid_t pid); + u64 partid; + + fn =3D symbol_get(mshv_pid_to_partid); + if (!fn) + return HV_PARTITION_ID_INVALID; + + partid =3D fn(current->tgid); + symbol_put(mshv_pid_to_partid); + + return partid; +} + +/* If this is a VMM thread, then this domain is for a guest VM */ +static bool hv_curr_thread_is_vmm(void) +{ + return hv_iommu_get_curr_partid() !=3D HV_PARTITION_ID_INVALID; +} + +static bool hv_iommu_capable(struct device *dev, enum iommu_cap cap) +{ + switch (cap) { + case IOMMU_CAP_CACHE_COHERENCY: + return true; + default: + return false; + } + return false; +} + +/* + * Check if given pci device is a direct attached device. Caller must have + * verified pdev is a valid pci device. + */ +bool hv_pcidev_is_attached_dev(struct pci_dev *pdev) +{ + struct iommu_domain *iommu_domain; + struct hv_domain *hvdom; + struct device *dev =3D &pdev->dev; + + iommu_domain =3D iommu_get_domain_for_dev(dev); + if (iommu_domain) { + hvdom =3D to_hv_domain(iommu_domain); + return hvdom->attached_dom; + } + + return false; +} +EXPORT_SYMBOL_GPL(hv_pcidev_is_attached_dev); + +/* Create a new device domain in the hypervisor */ +static int hv_iommu_create_hyp_devdom(struct hv_domain *hvdom) +{ + u64 status; + unsigned long flags; + struct hv_input_device_domain *ddp; + struct hv_input_create_device_domain *input; + + local_irq_save(flags); + input =3D *this_cpu_ptr(hyperv_pcpu_input_arg); + memset(input, 0, sizeof(*input)); + + ddp =3D &input->device_domain; + ddp->partition_id =3D HV_PARTITION_ID_SELF; + ddp->domain_id.type =3D HV_DEVICE_DOMAIN_TYPE_S2; + ddp->domain_id.id =3D hvdom->domid_num; + + input->create_device_domain_flags.forward_progress_required =3D 1; + input->create_device_domain_flags.inherit_owning_vtl =3D 0; + + status =3D hv_do_hypercall(HVCALL_CREATE_DEVICE_DOMAIN, input, NULL); + + local_irq_restore(flags); + + if (!hv_result_success(status)) + hv_status_err(status, "\n"); + + return hv_result_to_errno(status); +} + +/* During boot, all devices are attached to this */ +static struct iommu_domain *hv_iommu_domain_alloc_identity(struct device *= dev) +{ + return &hv_def_identity_dom.iommu_dom; +} + +static struct iommu_domain *hv_iommu_domain_alloc_paging(struct device *de= v) +{ + struct hv_domain *hvdom; + int rc; + + if (hv_l1vh_partition() && !hv_curr_thread_is_vmm() && !hv_no_attdev) { + pr_err("Hyper-V: l1vh iommu does not support host devices\n"); + return NULL; + } + + hvdom =3D kzalloc(sizeof(struct hv_domain), GFP_KERNEL); + if (hvdom =3D=3D NULL) + goto out; + + spin_lock_init(&hvdom->mappings_lock); + hvdom->mappings_tree =3D RB_ROOT_CACHED; + + if (++unique_id =3D=3D HV_DEVICE_DOMAIN_ID_S2_DEFAULT) /* ie, 0 */ + goto out_free; + + hvdom->domid_num =3D unique_id; + hvdom->iommu_dom.geometry =3D default_geometry; + hvdom->iommu_dom.pgsize_bitmap =3D HV_IOMMU_PGSIZES; + + /* For guests, by default we do direct attaches, so no domain in hyp */ + if (hv_curr_thread_is_vmm() && !hv_no_attdev) + hvdom->attached_dom =3D true; + else { + rc =3D hv_iommu_create_hyp_devdom(hvdom); + if (rc) + goto out_free_id; + } + + return &hvdom->iommu_dom; + +out_free_id: + unique_id--; +out_free: + kfree(hvdom); +out: + return NULL; +} + +static void hv_iommu_domain_free(struct iommu_domain *immdom) +{ + struct hv_domain *hvdom =3D to_hv_domain(immdom); + unsigned long flags; + u64 status; + struct hv_input_delete_device_domain *input; + + if (hv_special_domain(hvdom)) + return; + + if (hvdom->num_attchd) { + pr_err("Hyper-V: can't free busy iommu domain (%p)\n", immdom); + return; + } + + if (!hv_curr_thread_is_vmm() || hv_no_attdev) { + struct hv_input_device_domain *ddp; + + local_irq_save(flags); + input =3D *this_cpu_ptr(hyperv_pcpu_input_arg); + ddp =3D &input->device_domain; + memset(input, 0, sizeof(*input)); + + ddp->partition_id =3D HV_PARTITION_ID_SELF; + ddp->domain_id.type =3D HV_DEVICE_DOMAIN_TYPE_S2; + ddp->domain_id.id =3D hvdom->domid_num; + + status =3D hv_do_hypercall(HVCALL_DELETE_DEVICE_DOMAIN, input, + NULL); + local_irq_restore(flags); + + if (!hv_result_success(status)) + hv_status_err(status, "\n"); + } + + kfree(hvdom); +} + +/* Attach a device to a domain previously created in the hypervisor */ +static int hv_iommu_att_dev2dom(struct hv_domain *hvdom, struct pci_dev *p= dev) +{ + unsigned long flags; + u64 status; + enum hv_device_type dev_type; + struct hv_input_attach_device_domain *input; + + local_irq_save(flags); + input =3D *this_cpu_ptr(hyperv_pcpu_input_arg); + memset(input, 0, sizeof(*input)); + + input->device_domain.partition_id =3D HV_PARTITION_ID_SELF; + input->device_domain.domain_id.type =3D HV_DEVICE_DOMAIN_TYPE_S2; + input->device_domain.domain_id.id =3D hvdom->domid_num; + + /* NB: Upon guest shutdown, device is re-attached to the default domain + * without explicit detach. + */ + if (hv_l1vh_partition()) + dev_type =3D HV_DEVICE_TYPE_LOGICAL; + else + dev_type =3D HV_DEVICE_TYPE_PCI; + + input->device_id.as_uint64 =3D hv_build_devid_oftype(pdev, dev_type); + + status =3D hv_do_hypercall(HVCALL_ATTACH_DEVICE_DOMAIN, input, NULL); + local_irq_restore(flags); + + if (!hv_result_success(status)) + hv_status_err(status, "\n"); + + return hv_result_to_errno(status); +} + +/* Caller must have validated that dev is a valid pci dev */ +static int hv_iommu_direct_attach_device(struct pci_dev *pdev) +{ + struct hv_input_attach_device *input; + u64 status; + int rc; + unsigned long flags; + union hv_device_id host_devid; + enum hv_device_type dev_type; + u64 ptid =3D hv_iommu_get_curr_partid(); + + if (ptid =3D=3D HV_PARTITION_ID_INVALID) { + pr_err("Hyper-V: Invalid partition id in direct attach\n"); + return -EINVAL; + } + + if (hv_l1vh_partition()) + dev_type =3D HV_DEVICE_TYPE_LOGICAL; + else + dev_type =3D HV_DEVICE_TYPE_PCI; + + host_devid.as_uint64 =3D hv_build_devid_oftype(pdev, dev_type); + + do { + local_irq_save(flags); + input =3D *this_cpu_ptr(hyperv_pcpu_input_arg); + memset(input, 0, sizeof(*input)); + input->partition_id =3D ptid; + input->device_id =3D host_devid; + + /* Hypervisor associates logical_id with this device, and in + * some hypercalls like retarget interrupts, logical_id must be + * used instead of the BDF. It is a required parameter. + */ + input->attdev_flags.logical_id =3D 1; + input->logical_devid =3D + hv_build_devid_oftype(pdev, HV_DEVICE_TYPE_LOGICAL); + + status =3D hv_do_hypercall(HVCALL_ATTACH_DEVICE, input, NULL); + local_irq_restore(flags); + + if (hv_result(status) =3D=3D HV_STATUS_INSUFFICIENT_MEMORY) { + rc =3D hv_call_deposit_pages(NUMA_NO_NODE, ptid, 1); + if (rc) + break; + } + } while (hv_result(status) =3D=3D HV_STATUS_INSUFFICIENT_MEMORY); + + if (!hv_result_success(status)) + hv_status_err(status, "\n"); + + return hv_result_to_errno(status); +} + +/* This to attach a device to both host app (like DPDK) and a guest VM */ +static int hv_iommu_attach_dev(struct iommu_domain *immdom, struct device = *dev, + struct iommu_domain *old) +{ + struct pci_dev *pdev; + int rc; + struct hv_domain *hvdom_new =3D to_hv_domain(immdom); + struct hv_domain *hvdom_prev =3D dev_iommu_priv_get(dev); + + /* Only allow PCI devices for now */ + if (!dev_is_pci(dev)) + return -EINVAL; + + pdev =3D to_pci_dev(dev); + + /* l1vh does not support host device (eg DPDK) passthru */ + if (hv_l1vh_partition() && !hv_special_domain(hvdom_new) && + !hvdom_new->attached_dom) + return -EINVAL; + + /* + * VFIO does not do explicit detach calls, hence check first if we need + * to detach first. Also, in case of guest shutdown, it's the VMM + * thread that attaches it back to the hv_def_identity_dom, and + * hvdom_prev will not be null then. It is null during boot. + */ + if (hvdom_prev) + if (!hv_l1vh_partition() || !hv_special_domain(hvdom_prev)) + hv_iommu_detach_dev(&hvdom_prev->iommu_dom, dev); + + if (hv_l1vh_partition() && hv_special_domain(hvdom_new)) { + dev_iommu_priv_set(dev, hvdom_new); /* sets "private" field */ + return 0; + } + + if (hvdom_new->attached_dom) + rc =3D hv_iommu_direct_attach_device(pdev); + else + rc =3D hv_iommu_att_dev2dom(hvdom_new, pdev); + + if (rc && hvdom_prev) { + int rc1; + + if (hvdom_prev->attached_dom) + rc1 =3D hv_iommu_direct_attach_device(pdev); + else + rc1 =3D hv_iommu_att_dev2dom(hvdom_prev, pdev); + + if (rc1) + pr_err("Hyper-V: iommu could not restore orig device state.. dev:%s\n", + dev_name(dev)); + } + + if (rc =3D=3D 0) { + dev_iommu_priv_set(dev, hvdom_new); /* sets "private" field */ + hvdom_new->num_attchd++; + } + + return rc; +} + +static void hv_iommu_det_dev_from_guest(struct hv_domain *hvdom, + struct pci_dev *pdev) +{ + struct hv_input_detach_device *input; + u64 status, log_devid; + unsigned long flags; + + log_devid =3D hv_build_devid_oftype(pdev, HV_DEVICE_TYPE_LOGICAL); + + local_irq_save(flags); + input =3D *this_cpu_ptr(hyperv_pcpu_input_arg); + memset(input, 0, sizeof(*input)); + + input->partition_id =3D hv_iommu_get_curr_partid(); + input->logical_devid =3D log_devid; + status =3D hv_do_hypercall(HVCALL_DETACH_DEVICE, input, NULL); + local_irq_restore(flags); + + if (!hv_result_success(status)) + hv_status_err(status, "\n"); +} + +static void hv_iommu_det_dev_from_dom(struct hv_domain *hvdom, + struct pci_dev *pdev) +{ + u64 status, devid; + unsigned long flags; + struct hv_input_detach_device_domain *input; + + devid =3D hv_build_devid_oftype(pdev, HV_DEVICE_TYPE_PCI); + + local_irq_save(flags); + input =3D *this_cpu_ptr(hyperv_pcpu_input_arg); + memset(input, 0, sizeof(*input)); + + input->partition_id =3D HV_PARTITION_ID_SELF; + input->device_id.as_uint64 =3D devid; + status =3D hv_do_hypercall(HVCALL_DETACH_DEVICE_DOMAIN, input, NULL); + local_irq_restore(flags); + + if (!hv_result_success(status)) + hv_status_err(status, "\n"); +} + +static void hv_iommu_detach_dev(struct iommu_domain *immdom, struct device= *dev) +{ + struct pci_dev *pdev; + struct hv_domain *hvdom =3D to_hv_domain(immdom); + + /* See the attach function, only PCI devices for now */ + if (!dev_is_pci(dev)) + return; + + if (hvdom->num_attchd =3D=3D 0) + pr_warn("Hyper-V: num_attchd is zero (%s)\n", dev_name(dev)); + + pdev =3D to_pci_dev(dev); + + if (hvdom->attached_dom) { + hv_iommu_det_dev_from_guest(hvdom, pdev); + + /* Do not reset attached_dom, hv_iommu_unmap_pages happens + * next. + */ + } else { + hv_iommu_det_dev_from_dom(hvdom, pdev); + } + + hvdom->num_attchd--; +} + +static int hv_iommu_add_tree_mapping(struct hv_domain *hvdom, + unsigned long iova, phys_addr_t paddr, + size_t size, u32 flags) +{ + unsigned long irqflags; + struct hv_iommu_mapping *mapping; + + mapping =3D kzalloc(sizeof(*mapping), GFP_ATOMIC); + if (!mapping) + return -ENOMEM; + + mapping->paddr =3D paddr; + mapping->iova.start =3D iova; + mapping->iova.last =3D iova + size - 1; + mapping->flags =3D flags; + + spin_lock_irqsave(&hvdom->mappings_lock, irqflags); + interval_tree_insert(&mapping->iova, &hvdom->mappings_tree); + spin_unlock_irqrestore(&hvdom->mappings_lock, irqflags); + + return 0; +} + +static size_t hv_iommu_del_tree_mappings(struct hv_domain *hvdom, + unsigned long iova, size_t size) +{ + unsigned long flags; + size_t unmapped =3D 0; + unsigned long last =3D iova + size - 1; + struct hv_iommu_mapping *mapping =3D NULL; + struct interval_tree_node *node, *next; + + spin_lock_irqsave(&hvdom->mappings_lock, flags); + next =3D interval_tree_iter_first(&hvdom->mappings_tree, iova, last); + while (next) { + node =3D next; + mapping =3D container_of(node, struct hv_iommu_mapping, iova); + next =3D interval_tree_iter_next(node, iova, last); + + /* Trying to split a mapping? Not supported for now. */ + if (mapping->iova.start < iova) + break; + + unmapped +=3D mapping->iova.last - mapping->iova.start + 1; + + interval_tree_remove(node, &hvdom->mappings_tree); + kfree(mapping); + } + spin_unlock_irqrestore(&hvdom->mappings_lock, flags); + + return unmapped; +} + +/* Return: must return exact status from the hypercall without changes */ +static u64 hv_iommu_map_pgs(struct hv_domain *hvdom, + unsigned long iova, phys_addr_t paddr, + unsigned long npages, u32 map_flags) +{ + u64 status; + int i; + struct hv_input_map_device_gpa_pages *input; + unsigned long flags, pfn =3D paddr >> HV_HYP_PAGE_SHIFT; + + local_irq_save(flags); + input =3D *this_cpu_ptr(hyperv_pcpu_input_arg); + memset(input, 0, sizeof(*input)); + + input->device_domain.partition_id =3D HV_PARTITION_ID_SELF; + input->device_domain.domain_id.type =3D HV_DEVICE_DOMAIN_TYPE_S2; + input->device_domain.domain_id.id =3D hvdom->domid_num; + input->map_flags =3D map_flags; + input->target_device_va_base =3D iova; + + pfn =3D paddr >> HV_HYP_PAGE_SHIFT; + for (i =3D 0; i < npages; i++, pfn++) + input->gpa_page_list[i] =3D pfn; + + status =3D hv_do_rep_hypercall(HVCALL_MAP_DEVICE_GPA_PAGES, npages, 0, + input, NULL); + + local_irq_restore(flags); + return status; +} + +/* + * The core VFIO code loops over memory ranges calling this function with + * the largest size from HV_IOMMU_PGSIZES. cond_resched() is in vfio_iommu= _map. + */ +static int hv_iommu_map_pages(struct iommu_domain *immdom, ulong iova, + phys_addr_t paddr, size_t pgsize, size_t pgcount, + int prot, gfp_t gfp, size_t *mapped) +{ + u32 map_flags; + int ret; + u64 status; + unsigned long npages, done =3D 0; + struct hv_domain *hvdom =3D to_hv_domain(immdom); + size_t size =3D pgsize * pgcount; + + map_flags =3D HV_MAP_GPA_READABLE; /* required */ + map_flags |=3D prot & IOMMU_WRITE ? HV_MAP_GPA_WRITABLE : 0; + + ret =3D hv_iommu_add_tree_mapping(hvdom, iova, paddr, size, map_flags); + if (ret) + return ret; + + if (hvdom->attached_dom) { + *mapped =3D size; + return 0; + } + + npages =3D size >> HV_HYP_PAGE_SHIFT; + while (done < npages) { + ulong completed, remain =3D npages - done; + + status =3D hv_iommu_map_pgs(hvdom, iova, paddr, remain, + map_flags); + + completed =3D hv_repcomp(status); + done =3D done + completed; + iova =3D iova + (completed << HV_HYP_PAGE_SHIFT); + paddr =3D paddr + (completed << HV_HYP_PAGE_SHIFT); + + if (hv_result(status) =3D=3D HV_STATUS_INSUFFICIENT_MEMORY) { + ret =3D hv_call_deposit_pages(NUMA_NO_NODE, + hv_current_partition_id, + 256); + if (ret) + break; + } + if (!hv_result_success(status)) + break; + } + + if (!hv_result_success(status)) { + size_t done_size =3D done << HV_HYP_PAGE_SHIFT; + + hv_status_err(status, "pgs:%lx/%lx iova:%lx\n", + done, npages, iova); + /* + * lookup tree has all mappings [0 - size-1]. Below unmap will + * only remove from [0 - done], we need to remove second chunk + * [done+1 - size-1]. + */ + hv_iommu_del_tree_mappings(hvdom, iova, size - done_size); + hv_iommu_unmap_pages(immdom, iova - done_size, pgsize, + done, NULL); + if (mapped) + *mapped =3D 0; + } else + if (mapped) + *mapped =3D size; + + return hv_result_to_errno(status); +} + +static size_t hv_iommu_unmap_pages(struct iommu_domain *immdom, ulong iova, + size_t pgsize, size_t pgcount, + struct iommu_iotlb_gather *gather) +{ + unsigned long flags, npages; + struct hv_input_unmap_device_gpa_pages *input; + u64 status; + struct hv_domain *hvdom =3D to_hv_domain(immdom); + size_t unmapped, size =3D pgsize * pgcount; + + unmapped =3D hv_iommu_del_tree_mappings(hvdom, iova, size); + if (unmapped < size) + pr_err("%s: could not delete all mappings (%lx:%lx/%lx)\n", + __func__, iova, unmapped, size); + + if (hvdom->attached_dom) + return size; + + npages =3D size >> HV_HYP_PAGE_SHIFT; + + local_irq_save(flags); + input =3D *this_cpu_ptr(hyperv_pcpu_input_arg); + memset(input, 0, sizeof(*input)); + + input->device_domain.partition_id =3D HV_PARTITION_ID_SELF; + input->device_domain.domain_id.type =3D HV_DEVICE_DOMAIN_TYPE_S2; + input->device_domain.domain_id.id =3D hvdom->domid_num; + input->target_device_va_base =3D iova; + + status =3D hv_do_rep_hypercall(HVCALL_UNMAP_DEVICE_GPA_PAGES, npages, + 0, input, NULL); + local_irq_restore(flags); + + if (!hv_result_success(status)) + hv_status_err(status, "\n"); + + return unmapped; +} + +static phys_addr_t hv_iommu_iova_to_phys(struct iommu_domain *immdom, + dma_addr_t iova) +{ + u64 paddr =3D 0; + unsigned long flags; + struct hv_iommu_mapping *mapping; + struct interval_tree_node *node; + struct hv_domain *hvdom =3D to_hv_domain(immdom); + + spin_lock_irqsave(&hvdom->mappings_lock, flags); + node =3D interval_tree_iter_first(&hvdom->mappings_tree, iova, iova); + if (node) { + mapping =3D container_of(node, struct hv_iommu_mapping, iova); + paddr =3D mapping->paddr + (iova - mapping->iova.start); + } + spin_unlock_irqrestore(&hvdom->mappings_lock, flags); + + return paddr; +} + +/* + * Currently, hypervisor does not provide list of devices it is using + * dynamically. So use this to allow users to manually specify devices that + * should be skipped. (eg. hypervisor debugger using some network device). + */ +static struct iommu_device *hv_iommu_probe_device(struct device *dev) +{ + if (!dev_is_pci(dev)) + return ERR_PTR(-ENODEV); + + if (pci_devs_to_skip && *pci_devs_to_skip) { + int rc, pos =3D 0; + int parsed; + int segment, bus, slot, func; + struct pci_dev *pdev =3D to_pci_dev(dev); + + do { + parsed =3D 0; + + rc =3D sscanf(pci_devs_to_skip + pos, " (%x:%x:%x.%x) %n", + &segment, &bus, &slot, &func, &parsed); + if (rc) + break; + if (parsed <=3D 0) + break; + + if (pci_domain_nr(pdev->bus) =3D=3D segment && + pdev->bus->number =3D=3D bus && + PCI_SLOT(pdev->devfn) =3D=3D slot && + PCI_FUNC(pdev->devfn) =3D=3D func) { + + dev_info(dev, "skipped by Hyper-V IOMMU\n"); + return ERR_PTR(-ENODEV); + } + pos +=3D parsed; + + } while (pci_devs_to_skip[pos]); + } + + /* Device will be explicitly attached to the default domain, so no need + * to do dev_iommu_priv_set() here. + */ + + return &hv_virt_iommu; +} + +static void hv_iommu_probe_finalize(struct device *dev) +{ + struct iommu_domain *immdom =3D iommu_get_domain_for_dev(dev); + + if (immdom && immdom->type =3D=3D IOMMU_DOMAIN_DMA) + iommu_setup_dma_ops(dev); + else + set_dma_ops(dev, NULL); +} + +static void hv_iommu_release_device(struct device *dev) +{ + struct hv_domain *hvdom =3D dev_iommu_priv_get(dev); + + /* Need to detach device from device domain if necessary. */ + if (hvdom) + hv_iommu_detach_dev(&hvdom->iommu_dom, dev); + + dev_iommu_priv_set(dev, NULL); + set_dma_ops(dev, NULL); +} + +static struct iommu_group *hv_iommu_device_group(struct device *dev) +{ + if (dev_is_pci(dev)) + return pci_device_group(dev); + else + return generic_device_group(dev); +} + +static int hv_iommu_def_domain_type(struct device *dev) +{ + /* The hypervisor always creates this by default during boot */ + return IOMMU_DOMAIN_IDENTITY; +} + +static struct iommu_ops hv_iommu_ops =3D { + .capable =3D hv_iommu_capable, + .domain_alloc_identity =3D hv_iommu_domain_alloc_identity, + .domain_alloc_paging =3D hv_iommu_domain_alloc_paging, + .probe_device =3D hv_iommu_probe_device, + .probe_finalize =3D hv_iommu_probe_finalize, + .release_device =3D hv_iommu_release_device, + .def_domain_type =3D hv_iommu_def_domain_type, + .device_group =3D hv_iommu_device_group, + .default_domain_ops =3D &(const struct iommu_domain_ops) { + .attach_dev =3D hv_iommu_attach_dev, + .map_pages =3D hv_iommu_map_pages, + .unmap_pages =3D hv_iommu_unmap_pages, + .iova_to_phys =3D hv_iommu_iova_to_phys, + .free =3D hv_iommu_domain_free, + }, + .owner =3D THIS_MODULE, +}; + +static void __init hv_initialize_special_domains(void) +{ + hv_def_identity_dom.iommu_dom.geometry =3D default_geometry; + hv_def_identity_dom.domid_num =3D HV_DEVICE_DOMAIN_ID_S2_DEFAULT; /* 0 */ +} + +static int __init hv_iommu_init(void) +{ + int ret; + struct iommu_device *iommup =3D &hv_virt_iommu; + + if (!hv_is_hyperv_initialized()) + return -ENODEV; + + ret =3D iommu_device_sysfs_add(iommup, NULL, NULL, "%s", "hyperv-iommu"); + if (ret) { + pr_err("Hyper-V: iommu_device_sysfs_add failed: %d\n", ret); + return ret; + } + + /* This must come before iommu_device_register because the latter calls + * into the hooks. + */ + hv_initialize_special_domains(); + + ret =3D iommu_device_register(iommup, &hv_iommu_ops, NULL); + if (ret) { + pr_err("Hyper-V: iommu_device_register failed: %d\n", ret); + goto err_sysfs_remove; + } + + pr_info("Hyper-V IOMMU initialized\n"); + + return 0; + +err_sysfs_remove: + iommu_device_sysfs_remove(iommup); + return ret; +} + +void __init hv_iommu_detect(void) +{ + if (no_iommu || iommu_detected) + return; + + /* For l1vh, always expose an iommu unit */ + if (!hv_l1vh_partition()) + if (!(ms_hyperv.misc_features & HV_DEVICE_DOMAIN_AVAILABLE)) + return; + + iommu_detected =3D 1; + x86_init.iommu.iommu_init =3D hv_iommu_init; + + pci_request_acs(); +} diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h index dfc516c1c719..2ad111727e82 100644 --- a/include/linux/hyperv.h +++ b/include/linux/hyperv.h @@ -1767,4 +1767,10 @@ static inline unsigned long virt_to_hvpfn(void *addr) #define HVPFN_DOWN(x) ((x) >> HV_HYP_PAGE_SHIFT) #define page_to_hvpfn(page) (page_to_pfn(page) * NR_HV_HYP_PAGES_IN_PAGE) =20 +#ifdef CONFIG_HYPERV_IOMMU +void __init hv_iommu_detect(void); +#else +static inline void hv_iommu_detect(void) { } +#endif /* CONFIG_HYPERV_IOMMU */ + #endif /* _HYPERV_H */ --=20 2.51.2.vfs.0.1 From nobody Sat Feb 7 15:15:18 2026 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id C2F8E3904D1; Tue, 20 Jan 2026 06:43:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; 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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="WUo4duFo" Received: from mrdev.corp.microsoft.com (192-184-212-33.fiber.dynamic.sonic.net [192.184.212.33]) by linux.microsoft.com (Postfix) with ESMTPSA id C34CF20B716A; Mon, 19 Jan 2026 22:43:47 -0800 (PST) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com C34CF20B716A DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1768891428; bh=lrCNvS0KTmv8uGW/3D9TXCk8n/kSy8BeNKs2VH+PdxU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=WUo4duFom3CBzDyCu19ZnRecBUYp8n0SeTqWk9J+CY0/pdnqPS79j+NLppPdZJHRH AgkHKXVNd8Pos+JSoPunRIWjLiVBK8ZjDR3Xnzl72PCd0aZd3RD7TjhUxCD6EdDM0R RmI6/gSwPyF2Doi2co/U/mf/wzj6eRWLF83CoH7A= From: Mukesh R To: linux-kernel@vger.kernel.org, linux-hyperv@vger.kernel.org, linux-arm-kernel@lists.infradead.org, iommu@lists.linux.dev, linux-pci@vger.kernel.org, linux-arch@vger.kernel.org Cc: kys@microsoft.com, haiyangz@microsoft.com, wei.liu@kernel.org, decui@microsoft.com, longli@microsoft.com, catalin.marinas@arm.com, will@kernel.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com, joro@8bytes.org, lpieralisi@kernel.org, kwilczynski@kernel.org, mani@kernel.org, robh@kernel.org, bhelgaas@google.com, arnd@arndb.de, nunodasneves@linux.microsoft.com, mhklinux@outlook.com, romank@linux.microsoft.com Subject: [PATCH v0 13/15] x86/hyperv: Basic interrupt support for direct attached devices Date: Mon, 19 Jan 2026 22:42:28 -0800 Message-ID: <20260120064230.3602565-14-mrathor@linux.microsoft.com> X-Mailer: git-send-email 2.51.2.vfs.0.1 In-Reply-To: <20260120064230.3602565-1-mrathor@linux.microsoft.com> References: <20260120064230.3602565-1-mrathor@linux.microsoft.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Mukesh Rathor As mentioned previously, a direct attached device must be referenced via logical device id which is formed in the initial attach hypercall. Interrupt mapping paths for direct attached devices are almost same, except we must use logical device ids instead of the PCI device ids. L1VH only supports direct attaches for passing thru devices to its guests, and devices on L1VH are VMBus based. However, the interrupts are mapped via the map interrupt hypercall and not the traditional method of VMBus messages. Partition id for the relevant hypercalls is tricky. This because a device could be moving from root to guest and then back to the root. In case of L1VH, it could be moving from system host to L1VH root to a guest, then back to the L1VH root. So, it is carefully crafted by keeping track of whether the call is on behalf of a VMM process, whether the device is attached device (as opposed to mapped), and whether we are in an L1VH root/parent. If VMM process, we assume it is on behalf of a guest. Otherwise, the device is being attached or detached during boot or shutdown of the privileged partition. Lastly, a dummy cpu and vector is used to map interrupt for a direct attached device. This because, once a device is marked for direct attach, hypervisor will not let any interrupts be mapped to host. So it is mapped to guest dummy cpu and dummy vector. This is then correctly mapped during guest boot via the retarget paths. Signed-off-by: Mukesh Rathor --- arch/arm64/include/asm/mshyperv.h | 15 +++++ arch/x86/hyperv/irqdomain.c | 57 +++++++++++++----- arch/x86/include/asm/mshyperv.h | 4 ++ drivers/pci/controller/pci-hyperv.c | 91 +++++++++++++++++++++++++---- 4 files changed, 142 insertions(+), 25 deletions(-) diff --git a/arch/arm64/include/asm/mshyperv.h b/arch/arm64/include/asm/msh= yperv.h index b721d3134ab6..27da480f94f6 100644 --- a/arch/arm64/include/asm/mshyperv.h +++ b/arch/arm64/include/asm/mshyperv.h @@ -53,6 +53,21 @@ static inline u64 hv_get_non_nested_msr(unsigned int reg) return hv_get_msr(reg); } =20 +struct irq_data; +struct msi_msg; +struct pci_dev; +static inline void hv_irq_compose_msi_msg(struct irq_data *data, + struct msi_msg *msg) {}; +static inline int hv_unmap_msi_interrupt(struct pci_dev *pdev, + struct hv_interrupt_entry *hvirqe) +{ + return -EOPNOTSUPP; +} +static inline bool hv_pcidev_is_attached_dev(struct pci_dev *pdev) +{ + return false; +} + /* SMCCC hypercall parameters */ #define HV_SMCCC_FUNC_NUMBER 1 #define HV_FUNC_ID ARM_SMCCC_CALL_VAL( \ diff --git a/arch/x86/hyperv/irqdomain.c b/arch/x86/hyperv/irqdomain.c index 33017aa0caa4..e6eb457f791e 100644 --- a/arch/x86/hyperv/irqdomain.c +++ b/arch/x86/hyperv/irqdomain.c @@ -13,6 +13,16 @@ #include #include =20 +/* + * For direct attached devices (which use logical device ids), hypervisor = will + * not allow mappings to host. But VFIO needs to bind the interrupt at the= very + * start before the guest cpu/vector is known. So we use dummy cpu and vec= tor + * to bind in such case, and later when the guest starts, retarget will mo= ve it + * to correct guest cpu and vector. + */ +#define HV_DDA_DUMMY_CPU 0 +#define HV_DDA_DUMMY_VECTOR 32 + static u64 hv_map_interrupt_hcall(u64 ptid, union hv_device_id hv_devid, bool level, int cpu, int vector, struct hv_interrupt_entry *ret_entry) @@ -24,6 +34,11 @@ static u64 hv_map_interrupt_hcall(u64 ptid, union hv_dev= ice_id hv_devid, u64 status; int nr_bank, var_size; =20 + if (hv_devid.device_type =3D=3D HV_DEVICE_TYPE_LOGICAL) { + cpu =3D HV_DDA_DUMMY_CPU; + vector =3D HV_DDA_DUMMY_VECTOR; + } + local_irq_save(flags); =20 input =3D *this_cpu_ptr(hyperv_pcpu_input_arg); @@ -95,7 +110,8 @@ static int hv_map_interrupt(u64 ptid, union hv_device_id= device_id, bool level, return hv_result_to_errno(status); } =20 -static int hv_unmap_interrupt(u64 id, struct hv_interrupt_entry *irq_entry) +static int hv_unmap_interrupt(union hv_device_id hv_devid, + struct hv_interrupt_entry *irq_entry) { unsigned long flags; struct hv_input_unmap_device_interrupt *input; @@ -103,10 +119,14 @@ static int hv_unmap_interrupt(u64 id, struct hv_inter= rupt_entry *irq_entry) =20 local_irq_save(flags); input =3D *this_cpu_ptr(hyperv_pcpu_input_arg); - memset(input, 0, sizeof(*input)); - input->partition_id =3D hv_current_partition_id; - input->device_id =3D id; + + if (hv_devid.device_type =3D=3D HV_DEVICE_TYPE_LOGICAL) + input->partition_id =3D hv_iommu_get_curr_partid(); + else + input->partition_id =3D hv_current_partition_id; + + input->device_id =3D hv_devid.as_uint64; input->interrupt_entry =3D *irq_entry; =20 status =3D hv_do_hypercall(HVCALL_UNMAP_DEVICE_INTERRUPT, input, NULL); @@ -263,6 +283,7 @@ static u64 hv_build_irq_devid(struct pci_dev *pdev) int hv_map_msi_interrupt(struct irq_data *data, struct hv_interrupt_entry *out_entry) { + u64 ptid; struct irq_cfg *cfg =3D irqd_cfg(data); struct hv_interrupt_entry dummy; union hv_device_id hv_devid; @@ -275,8 +296,17 @@ int hv_map_msi_interrupt(struct irq_data *data, hv_devid.as_uint64 =3D hv_build_irq_devid(pdev); cpu =3D cpumask_first(irq_data_get_effective_affinity_mask(data)); =20 - return hv_map_interrupt(hv_current_partition_id, hv_devid, false, cpu, - cfg->vector, out_entry ? out_entry : &dummy); + if (hv_devid.device_type =3D=3D HV_DEVICE_TYPE_LOGICAL) + if (hv_pcidev_is_attached_dev(pdev)) + ptid =3D hv_iommu_get_curr_partid(); + else + /* Device actually on l1vh root, not passthru'd to vm */ + ptid =3D hv_current_partition_id; + else + ptid =3D hv_current_partition_id; + + return hv_map_interrupt(ptid, hv_devid, false, cpu, cfg->vector, + out_entry ? out_entry : &dummy); } EXPORT_SYMBOL_GPL(hv_map_msi_interrupt); =20 @@ -289,10 +319,7 @@ static void entry_to_msi_msg(struct hv_interrupt_entry= *entry, msg->data =3D entry->msi_entry.data.as_uint32; } =20 -static int hv_unmap_msi_interrupt(struct pci_dev *pdev, - struct hv_interrupt_entry *irq_entry); - -static void hv_irq_compose_msi_msg(struct irq_data *data, struct msi_msg *= msg) +void hv_irq_compose_msi_msg(struct irq_data *data, struct msi_msg *msg) { struct hv_interrupt_entry *stored_entry; struct irq_cfg *cfg =3D irqd_cfg(data); @@ -341,16 +368,18 @@ static void hv_irq_compose_msi_msg(struct irq_data *d= ata, struct msi_msg *msg) data->chip_data =3D stored_entry; entry_to_msi_msg(data->chip_data, msg); } +EXPORT_SYMBOL_GPL(hv_irq_compose_msi_msg); =20 -static int hv_unmap_msi_interrupt(struct pci_dev *pdev, - struct hv_interrupt_entry *irq_entry) +int hv_unmap_msi_interrupt(struct pci_dev *pdev, + struct hv_interrupt_entry *irq_entry) { union hv_device_id hv_devid; =20 hv_devid.as_uint64 =3D hv_build_irq_devid(pdev); =20 - return hv_unmap_interrupt(hv_devid.as_uint64, irq_entry); + return hv_unmap_interrupt(hv_devid, irq_entry); } +EXPORT_SYMBOL_GPL(hv_unmap_msi_interrupt); =20 /* NB: during map, hv_interrupt_entry is saved via data->chip_data */ static void hv_teardown_msi_irq(struct pci_dev *pdev, struct irq_data *irq= d) @@ -486,7 +515,7 @@ int hv_unmap_ioapic_interrupt(int ioapic_id, struct hv_= interrupt_entry *entry) hv_devid.device_type =3D HV_DEVICE_TYPE_IOAPIC; hv_devid.ioapic.ioapic_id =3D (u8)ioapic_id; =20 - return hv_unmap_interrupt(hv_devid.as_uint64, entry); + return hv_unmap_interrupt(hv_devid, entry); } EXPORT_SYMBOL_GPL(hv_unmap_ioapic_interrupt); =20 diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyper= v.h index e4ccdbbf1d12..b6facd3a0f5e 100644 --- a/arch/x86/include/asm/mshyperv.h +++ b/arch/x86/include/asm/mshyperv.h @@ -204,11 +204,15 @@ static inline u64 hv_iommu_get_curr_partid(void) #endif /* CONFIG_HYPERV_IOMMU */ =20 u64 hv_pci_vmbus_device_id(struct pci_dev *pdev); +void hv_irq_compose_msi_msg(struct irq_data *data, struct msi_msg *msg); +extern bool hv_no_attdev; =20 struct irq_domain *hv_create_pci_msi_domain(void); =20 int hv_map_msi_interrupt(struct irq_data *data, struct hv_interrupt_entry *out_entry); +int hv_unmap_msi_interrupt(struct pci_dev *dev, + struct hv_interrupt_entry *hvirqe); int hv_map_ioapic_interrupt(int ioapic_id, bool level, int vcpu, int vecto= r, struct hv_interrupt_entry *entry); int hv_unmap_ioapic_interrupt(int ioapic_id, struct hv_interrupt_entry *en= try); diff --git a/drivers/pci/controller/pci-hyperv.c b/drivers/pci/controller/p= ci-hyperv.c index 40f0b06bb966..71d1599dc4a8 100644 --- a/drivers/pci/controller/pci-hyperv.c +++ b/drivers/pci/controller/pci-hyperv.c @@ -660,15 +660,17 @@ static void hv_irq_retarget_interrupt(struct irq_data= *data) =20 params =3D *this_cpu_ptr(hyperv_pcpu_input_arg); memset(params, 0, sizeof(*params)); - params->partition_id =3D HV_PARTITION_ID_SELF; + + if (hv_pcidev_is_attached_dev(pdev)) + params->partition_id =3D hv_iommu_get_curr_partid(); + else + params->partition_id =3D HV_PARTITION_ID_SELF; + params->int_entry.source =3D HV_INTERRUPT_SOURCE_MSI; - params->int_entry.msi_entry.address.as_uint32 =3D int_desc->address & 0xf= fffffff; + params->int_entry.msi_entry.address.as_uint32 =3D + int_desc->address & 0xffffffff; params->int_entry.msi_entry.data.as_uint32 =3D int_desc->data; - params->device_id =3D (hbus->hdev->dev_instance.b[5] << 24) | - (hbus->hdev->dev_instance.b[4] << 16) | - (hbus->hdev->dev_instance.b[7] << 8) | - (hbus->hdev->dev_instance.b[6] & 0xf8) | - PCI_FUNC(pdev->devfn); + params->device_id =3D hv_pci_vmbus_device_id(pdev); params->int_target.vector =3D hv_msi_get_int_vector(data); =20 if (hbus->protocol_version >=3D PCI_PROTOCOL_VERSION_1_2) { @@ -1263,6 +1265,15 @@ static void _hv_pcifront_read_config(struct hv_pci_d= ev *hpdev, int where, mb(); } spin_unlock_irqrestore(&hbus->config_lock, flags); + /* + * Make sure PCI_INTERRUPT_PIN is hard-wired to 0 since it may + * be read using a 32bit read which is skipped by the above + * emulation. + */ + if (PCI_INTERRUPT_PIN >=3D where && + PCI_INTERRUPT_PIN <=3D (where + size)) { + *((char *)val + PCI_INTERRUPT_PIN - where) =3D 0; + } } else { dev_err(dev, "Attempt to read beyond a function's config space.\n"); } @@ -1731,14 +1742,22 @@ static void hv_msi_free(struct irq_domain *domain, = unsigned int irq) if (!int_desc) return; =20 - irq_data->chip_data =3D NULL; hpdev =3D get_pcichild_wslot(hbus, devfn_to_wslot(pdev->devfn)); if (!hpdev) { + irq_data->chip_data =3D NULL; kfree(int_desc); return; } =20 - hv_int_desc_free(hpdev, int_desc); + if (hv_pcidev_is_attached_dev(pdev)) { + hv_unmap_msi_interrupt(pdev, irq_data->chip_data); + kfree(irq_data->chip_data); + irq_data->chip_data =3D NULL; + } else { + irq_data->chip_data =3D NULL; + hv_int_desc_free(hpdev, int_desc); + } + put_pcichild(hpdev); } =20 @@ -2139,6 +2158,56 @@ static void hv_vmbus_compose_msi_msg(struct irq_data= *data, struct msi_msg *msg) msg->data =3D 0; } =20 +/* Compose an msi message for a directly attached device */ +static void hv_dda_compose_msi_msg(struct irq_data *irq_data, + struct msi_desc *msi_desc, + struct msi_msg *msg) +{ + bool multi_msi; + struct hv_pcibus_device *hbus; + struct hv_pci_dev *hpdev; + struct pci_dev *pdev =3D msi_desc_to_pci_dev(msi_desc); + + multi_msi =3D !msi_desc->pci.msi_attrib.is_msix && + msi_desc->nvec_used > 1; + + if (multi_msi) { + dev_err(&hbus->hdev->device, + "Passthru direct attach does not support multi msi\n"); + goto outerr; + } + + hbus =3D container_of(pdev->bus->sysdata, struct hv_pcibus_device, + sysdata); + + hpdev =3D get_pcichild_wslot(hbus, devfn_to_wslot(pdev->devfn)); + if (!hpdev) + goto outerr; + + /* will unmap if needed and also update irq_data->chip_data */ + hv_irq_compose_msi_msg(irq_data, msg); + + put_pcichild(hpdev); + return; + +outerr: + memset(msg, 0, sizeof(*msg)); +} + +static void hv_compose_msi_msg(struct irq_data *data, struct msi_msg *msg) +{ + struct pci_dev *pdev; + struct msi_desc *msi_desc; + + msi_desc =3D irq_data_get_msi_desc(data); + pdev =3D msi_desc_to_pci_dev(msi_desc); + + if (hv_pcidev_is_attached_dev(pdev)) + hv_dda_compose_msi_msg(data, msi_desc, msg); + else + hv_vmbus_compose_msi_msg(data, msg); +} + static bool hv_pcie_init_dev_msi_info(struct device *dev, struct irq_domai= n *domain, struct irq_domain *real_parent, struct msi_domain_info *info) { @@ -2177,7 +2246,7 @@ static const struct msi_parent_ops hv_pcie_msi_parent= _ops =3D { /* HW Interrupt Chip Descriptor */ static struct irq_chip hv_msi_irq_chip =3D { .name =3D "Hyper-V PCIe MSI", - .irq_compose_msi_msg =3D hv_vmbus_compose_msi_msg, + .irq_compose_msi_msg =3D hv_compose_msi_msg, .irq_set_affinity =3D irq_chip_set_affinity_parent, .irq_ack =3D irq_chip_ack_parent, .irq_eoi =3D irq_chip_eoi_parent, @@ -4096,7 +4165,7 @@ static int hv_pci_restore_msi_msg(struct pci_dev *pde= v, void *arg) irq_data =3D irq_get_irq_data(entry->irq); if (WARN_ON_ONCE(!irq_data)) return -EINVAL; - hv_vmbus_compose_msi_msg(irq_data, &entry->msg); + hv_compose_msi_msg(irq_data, &entry->msg); } return 0; } --=20 2.51.2.vfs.0.1 From nobody Sat Feb 7 15:15:18 2026 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id A997B39902D; Tue, 20 Jan 2026 06:43:50 +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=1768891440; cv=none; b=u0d9mKCNsr01ktJEhlMYWQmAUdh95F/W4WVBRCk4E/hPrI/v8OTtQw9uuXST3xMpRbrQ/Vw421TO1ZaNatXyELt8m/xBgtAqj+u/6+H1CKxBp3brnpRRnVDSKwNDQdk18hb5CWd1bI5NiR5kTV5YHLrC+kZxP3I6M0DbGLI5mBE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768891440; c=relaxed/simple; bh=+8Qir+mOSVaBv5WqSoKuLu6sxNU4FaFzM6MVmGwCQN8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=REoaSZ1XMvYOqNUXg9Xi/6K3wdjl4u6DZhNepyxCKK0KFUdUJY/7edyCeMSUrYwefNdRgdEhA7MQGEw4EkSo+qA7wM1IoT/Hp65yjCdW9z5T2UCXdUBLT+I8dJriJZN0HJIFNwY1IH8nq105BiaZ9Azi/Es0iQXqz9ZmC6OIUwU= ARC-Authentication-Results: i=1; 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bh=CFz+8gqoAFM3TYZVTFHJmJB8DMHyjUBersKypxC41pc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=g77JY4hFKZt4z08YLR0YZzPxYsievzoO9oT+MmmeCnQaJOTE1AYBr6CrbTfBE0L6N TnMwk/PF6bC2vogLeTMWTIN/KKILat0XYJgYcsjHR3nbXUO62aw+XbqFPpASY8uVwb JoXRtxbs0LfE0/WkwvkUDdsKlFi+412LYl/5jhoU= From: Mukesh R To: linux-kernel@vger.kernel.org, linux-hyperv@vger.kernel.org, linux-arm-kernel@lists.infradead.org, iommu@lists.linux.dev, linux-pci@vger.kernel.org, linux-arch@vger.kernel.org Cc: kys@microsoft.com, haiyangz@microsoft.com, wei.liu@kernel.org, decui@microsoft.com, longli@microsoft.com, catalin.marinas@arm.com, will@kernel.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com, joro@8bytes.org, lpieralisi@kernel.org, kwilczynski@kernel.org, mani@kernel.org, robh@kernel.org, bhelgaas@google.com, arnd@arndb.de, nunodasneves@linux.microsoft.com, mhklinux@outlook.com, romank@linux.microsoft.com Subject: [PATCH v0 14/15] mshv: Remove mapping of mmio space during map user ioctl Date: Mon, 19 Jan 2026 22:42:29 -0800 Message-ID: <20260120064230.3602565-15-mrathor@linux.microsoft.com> X-Mailer: git-send-email 2.51.2.vfs.0.1 In-Reply-To: <20260120064230.3602565-1-mrathor@linux.microsoft.com> References: <20260120064230.3602565-1-mrathor@linux.microsoft.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Mukesh Rathor VFIO no longer puts the mmio pfn in vma->vm_pgoff. So, remove code that is using it to map mmio space. It is broken and will cause panic. Signed-off-by: Mukesh Rathor --- drivers/hv/mshv_root_main.c | 20 ++++---------------- 1 file changed, 4 insertions(+), 16 deletions(-) diff --git a/drivers/hv/mshv_root_main.c b/drivers/hv/mshv_root_main.c index 27313419828d..03f3aa9f5541 100644 --- a/drivers/hv/mshv_root_main.c +++ b/drivers/hv/mshv_root_main.c @@ -1258,16 +1258,8 @@ static int mshv_prepare_pinned_region(struct mshv_me= m_region *region) } =20 /* - * This maps two things: guest RAM and for pci passthru mmio space. - * - * mmio: - * - vfio overloads vm_pgoff to store the mmio start pfn/spa. - * - Two things need to happen for mapping mmio range: - * 1. mapped in the uaddr so VMM can access it. - * 2. mapped in the hwpt (gfn <-> mmio phys addr) so guest can access it. - * - * This function takes care of the second. The first one is managed by v= fio, - * and hence is taken care of via vfio_pci_mmap_fault(). + * This is called for both user ram and mmio space. The mmio space is not + * mapped here, but later during intercept. */ static long mshv_map_user_memory(struct mshv_partition *partition, @@ -1276,7 +1268,6 @@ mshv_map_user_memory(struct mshv_partition *partition, struct mshv_mem_region *region; struct vm_area_struct *vma; bool is_mmio; - ulong mmio_pfn; long ret; =20 if (mem.flags & BIT(MSHV_SET_MEM_BIT_UNMAP) || @@ -1286,7 +1277,6 @@ mshv_map_user_memory(struct mshv_partition *partition, mmap_read_lock(current->mm); vma =3D vma_lookup(current->mm, mem.userspace_addr); is_mmio =3D vma ? !!(vma->vm_flags & (VM_IO | VM_PFNMAP)) : 0; - mmio_pfn =3D is_mmio ? vma->vm_pgoff : 0; mmap_read_unlock(current->mm); =20 if (!vma) @@ -1313,10 +1303,8 @@ mshv_map_user_memory(struct mshv_partition *partitio= n, HV_MAP_GPA_NO_ACCESS, NULL); break; case MSHV_REGION_TYPE_MMIO: - ret =3D hv_call_map_mmio_pages(partition->pt_id, - region->start_gfn, - mmio_pfn, - region->nr_pages); + /* mmio mappings are handled later during intercepts */ + ret =3D 0; break; } =20 --=20 2.51.2.vfs.0.1 From nobody Sat Feb 7 15:15:18 2026 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 2E39F39A808; Tue, 20 Jan 2026 06:43:52 +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=1768891439; cv=none; b=CBZ/Lq9U7EMfcIslagKnc93PUcJBQbb4zbp5BiGs0G7YKObVB+Eo7YQd6PakzcdxJUCcZ8FlHDRjWHZn+dkkmUzaDYlzoHXm1CY4C51P0gvXLD+38dCAYWLVHxGWzN0aryjCrlHh+V/7QWKStHGqXJoDFQ98bVa/pOPdLEdExW4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768891439; c=relaxed/simple; bh=lFCdL+6ojHEEiti/5oEEzqcHgGMBpFffGSnL89hXCKs=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=qxZlcLg2Wr0qLWDvrQaALZ36fBW02RT7W0VVjtMf9dPxu8RAi5ODLdxPbFq6n2wPqWdcXN8hhoHNhSp0JV+fYKkxm5HQT4gvO610c12OrzDkjK22tK0ShswihaAFdveyU8LUS9k8sIwkSCzJnXrKNI4jji54/ZRxrKx0GHhJcuU= 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=nPKgQKZQ; 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="nPKgQKZQ" Received: from mrdev.corp.microsoft.com (192-184-212-33.fiber.dynamic.sonic.net [192.184.212.33]) by linux.microsoft.com (Postfix) with ESMTPSA id 795D320B716D; Mon, 19 Jan 2026 22:43:50 -0800 (PST) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 795D320B716D DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1768891431; bh=vwKC6HwtuqTh63I/EcCnX9kz02TP/FLMLkDGVcBN5Jg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=nPKgQKZQP36at7Pw9ekyrrLYOUWnS9INVzf/0p/e0spMOrWzbrSFIdbBIYmCgu9Yl 48+3TE7z+OgQ6l8v5rUbjC5ExL0L5TS/agbqGuSQ32EEIyWVA0e4BzSdoH7oe9rgAX 6TseUo1oxO/Z0ZpmEfj8TIL4CIuSoguKL/aCkpmA= From: Mukesh R To: linux-kernel@vger.kernel.org, linux-hyperv@vger.kernel.org, linux-arm-kernel@lists.infradead.org, iommu@lists.linux.dev, linux-pci@vger.kernel.org, linux-arch@vger.kernel.org Cc: kys@microsoft.com, haiyangz@microsoft.com, wei.liu@kernel.org, decui@microsoft.com, longli@microsoft.com, catalin.marinas@arm.com, will@kernel.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com, joro@8bytes.org, lpieralisi@kernel.org, kwilczynski@kernel.org, mani@kernel.org, robh@kernel.org, bhelgaas@google.com, arnd@arndb.de, nunodasneves@linux.microsoft.com, mhklinux@outlook.com, romank@linux.microsoft.com Subject: [PATCH v0 15/15] mshv: Populate mmio mappings for PCI passthru Date: Mon, 19 Jan 2026 22:42:30 -0800 Message-ID: <20260120064230.3602565-16-mrathor@linux.microsoft.com> X-Mailer: git-send-email 2.51.2.vfs.0.1 In-Reply-To: <20260120064230.3602565-1-mrathor@linux.microsoft.com> References: <20260120064230.3602565-1-mrathor@linux.microsoft.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Mukesh Rathor Upon guest access, in case of missing mmio mapping, the hypervisor generates an unmapped gpa intercept. In this path, lookup the PCI resource pfn for the guest gpa, and ask the hypervisor to map it via hypercall. The PCI resource pfn is maintained by the VFIO driver, and obtained via fixup_user_fault call (similar to KVM). Signed-off-by: Mukesh Rathor --- drivers/hv/mshv_root_main.c | 115 ++++++++++++++++++++++++++++++++++++ 1 file changed, 115 insertions(+) diff --git a/drivers/hv/mshv_root_main.c b/drivers/hv/mshv_root_main.c index 03f3aa9f5541..4c8bc7cd0888 100644 --- a/drivers/hv/mshv_root_main.c +++ b/drivers/hv/mshv_root_main.c @@ -56,6 +56,14 @@ struct hv_stats_page { }; } __packed; =20 +bool hv_nofull_mmio; /* don't map entire mmio region upon fault */ +static int __init setup_hv_full_mmio(char *str) +{ + hv_nofull_mmio =3D true; + return 0; +} +__setup("hv_nofull_mmio", setup_hv_full_mmio); + struct mshv_root mshv_root; =20 enum hv_scheduler_type hv_scheduler_type; @@ -612,6 +620,109 @@ mshv_partition_region_by_gfn(struct mshv_partition *p= artition, u64 gfn) } =20 #ifdef CONFIG_X86_64 + +/* + * Check if uaddr is for mmio range. If yes, return 0 with mmio_pfn filled= in + * else just return -errno. + */ +static int mshv_chk_get_mmio_start_pfn(struct mshv_partition *pt, u64 gfn, + u64 *mmio_pfnp) +{ + struct vm_area_struct *vma; + bool is_mmio; + u64 uaddr; + struct mshv_mem_region *mreg; + struct follow_pfnmap_args pfnmap_args; + int rc =3D -EINVAL; + + /* + * Do not allow mem region to be deleted beneath us. VFIO uses + * useraddr vma to lookup pci bar pfn. + */ + spin_lock(&pt->pt_mem_regions_lock); + + /* Get the region again under the lock */ + mreg =3D mshv_partition_region_by_gfn(pt, gfn); + if (mreg =3D=3D NULL || mreg->type !=3D MSHV_REGION_TYPE_MMIO) + goto unlock_pt_out; + + uaddr =3D mreg->start_uaddr + + ((gfn - mreg->start_gfn) << HV_HYP_PAGE_SHIFT); + + mmap_read_lock(current->mm); + vma =3D vma_lookup(current->mm, uaddr); + is_mmio =3D vma ? !!(vma->vm_flags & (VM_IO | VM_PFNMAP)) : 0; + if (!is_mmio) + goto unlock_mmap_out; + + pfnmap_args.vma =3D vma; + pfnmap_args.address =3D uaddr; + + rc =3D follow_pfnmap_start(&pfnmap_args); + if (rc) { + rc =3D fixup_user_fault(current->mm, uaddr, FAULT_FLAG_WRITE, + NULL); + if (rc) + goto unlock_mmap_out; + + rc =3D follow_pfnmap_start(&pfnmap_args); + if (rc) + goto unlock_mmap_out; + } + + *mmio_pfnp =3D pfnmap_args.pfn; + follow_pfnmap_end(&pfnmap_args); + +unlock_mmap_out: + mmap_read_unlock(current->mm); +unlock_pt_out: + spin_unlock(&pt->pt_mem_regions_lock); + return rc; +} + +/* + * At present, the only unmapped gpa is mmio space. Verify if it's mmio + * and resolve if possible. + * Returns: True if valid mmio intercept and it was handled, else false + */ +static bool mshv_handle_unmapped_gpa(struct mshv_vp *vp) +{ + struct hv_message *hvmsg =3D vp->vp_intercept_msg_page; + struct hv_x64_memory_intercept_message *msg; + union hv_x64_memory_access_info accinfo; + u64 gfn, mmio_spa, numpgs; + struct mshv_mem_region *mreg; + int rc; + struct mshv_partition *pt =3D vp->vp_partition; + + msg =3D (struct hv_x64_memory_intercept_message *)hvmsg->u.payload; + accinfo =3D msg->memory_access_info; + + if (!accinfo.gva_gpa_valid) + return false; + + /* Do a fast check and bail if non mmio intercept */ + gfn =3D msg->guest_physical_address >> HV_HYP_PAGE_SHIFT; + mreg =3D mshv_partition_region_by_gfn(pt, gfn); + if (mreg =3D=3D NULL || mreg->type !=3D MSHV_REGION_TYPE_MMIO) + return false; + + rc =3D mshv_chk_get_mmio_start_pfn(pt, gfn, &mmio_spa); + if (rc) + return false; + + if (!hv_nofull_mmio) { /* default case */ + gfn =3D mreg->start_gfn; + mmio_spa =3D mmio_spa - (gfn - mreg->start_gfn); + numpgs =3D mreg->nr_pages; + } else + numpgs =3D 1; + + rc =3D hv_call_map_mmio_pages(pt->pt_id, gfn, mmio_spa, numpgs); + + return rc =3D=3D 0; +} + static struct mshv_mem_region * mshv_partition_region_by_gfn_get(struct mshv_partition *p, u64 gfn) { @@ -666,13 +777,17 @@ static bool mshv_handle_gpa_intercept(struct mshv_vp = *vp) =20 return ret; } + #else /* CONFIG_X86_64 */ +static bool mshv_handle_unmapped_gpa(struct mshv_vp *vp) { return false; } static bool mshv_handle_gpa_intercept(struct mshv_vp *vp) { return false; } #endif /* CONFIG_X86_64 */ =20 static bool mshv_vp_handle_intercept(struct mshv_vp *vp) { switch (vp->vp_intercept_msg_page->header.message_type) { + case HVMSG_UNMAPPED_GPA: + return mshv_handle_unmapped_gpa(vp); case HVMSG_GPA_INTERCEPT: return mshv_handle_gpa_intercept(vp); } --=20 2.51.2.vfs.0.1