From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030848AbbJ3VNP (ORCPT ); Fri, 30 Oct 2015 17:13:15 -0400 Received: from o1.f.az.sendgrid.net ([208.117.55.132]:53662 "EHLO o1.f.az.sendgrid.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932957AbbJ3VME (ORCPT ); Fri, 30 Oct 2015 17:12:04 -0400 From: jakeo@microsoft.com To: gregkh@linuxfoundation.org, kys@microsoft.com, linux-kernel@vger.kernel.org, devel@linuxdriverproject.org, olaf@aepfle.de, apw@canonical.com, vkuznets@redhat.com, tglx@redhat.com, haiyangz@microsoft.com, marc.zyngier@arm.com, bhelgaas@google.com, linux-pci@vger.kernel.org Cc: Jake Oshins Subject: [PATCH v5 7/7] PCI: hv: New paravirtual PCI front-end for Hyper-V VMs Date: Fri, 30 Oct 2015 21:11:15 +0000 Message-Id: <1446239475-49480-8-git-send-email-jakeo@microsoft.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1446239475-49480-1-git-send-email-jakeo@microsoft.com> References: <1446239475-49480-1-git-send-email-jakeo@microsoft.com> X-SG-EID: UsLXQ589HNP4HLBydmD9pgHURQozLYm9XliudupI8YumM5FEf40nwm1aYflwkJKtQHyK25XiFiy6by a9bf24LoC2G4EpQa/UWA6wRSNyQZGHPAe/rAf9dSP/DM+HXB4+COMMWEhWhd80P/RcUSewcQF/h2RS AaQRoDOXXMxsrlyARq5ZMuG4+yFguak2uZzE Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jake Oshins This patch introduces a new driver which exposes a root PCI bus whenever a PCI Express device is passed through to a guest VM under Hyper-V. The device can be single- or multi-function. The interrupts for the devices are managed by an IRQ domain, implemented within the driver. Signed-off-by: Jake Oshins --- MAINTAINERS | 1 + drivers/pci/Kconfig | 7 + drivers/pci/host/Makefile | 1 + drivers/pci/host/hv_pcifront.c | 2267 ++++++++++++++++++++++++++++++++++++++++ 4 files changed, 2276 insertions(+) create mode 100644 drivers/pci/host/hv_pcifront.c diff --git a/MAINTAINERS b/MAINTAINERS index a2d50fe..a1205b4 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -5073,6 +5073,7 @@ F: arch/x86/kernel/cpu/mshyperv.c F: drivers/hid/hid-hyperv.c F: drivers/hv/ F: drivers/input/serio/hyperv-keyboard.c +F: drivers/pci/host/hv_pcifront.c F: drivers/net/hyperv/ F: drivers/scsi/storvsc_drv.c F: drivers/video/fbdev/hyperv_fb.c diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig index 73de4ef..9b82d93 100644 --- a/drivers/pci/Kconfig +++ b/drivers/pci/Kconfig @@ -118,4 +118,11 @@ config PCI_LABEL def_bool y if (DMI || ACPI) select NLS +config HYPERV_VPCI + tristate "Hyper-V PCI Frontend" + depends on PCI && X86 && HYPERV && PCI_MSI && PCI_MSI_IRQ_DOMAIN + help + The PCI device frontend driver allows the kernel to import arbitrary + PCI devices from a PCI backend to support PCI driver domains. + source "drivers/pci/host/Kconfig" diff --git a/drivers/pci/host/Makefile b/drivers/pci/host/Makefile index 140d66f..39581fb 100644 --- a/drivers/pci/host/Makefile +++ b/drivers/pci/host/Makefile @@ -2,6 +2,7 @@ obj-$(CONFIG_PCIE_DW) += pcie-designware.o obj-$(CONFIG_PCI_DRA7XX) += pci-dra7xx.o obj-$(CONFIG_PCI_EXYNOS) += pci-exynos.o obj-$(CONFIG_PCI_IMX6) += pci-imx6.o +obj-$(CONFIG_HYPERV_VPCI) += hv_pcifront.o obj-$(CONFIG_PCI_MVEBU) += pci-mvebu.o obj-$(CONFIG_PCI_TEGRA) += pci-tegra.o obj-$(CONFIG_PCI_RCAR_GEN2) += pci-rcar-gen2.o diff --git a/drivers/pci/host/hv_pcifront.c b/drivers/pci/host/hv_pcifront.c new file mode 100644 index 0000000..73f296e --- /dev/null +++ b/drivers/pci/host/hv_pcifront.c @@ -0,0 +1,2267 @@ +/* + * Copyright (c) Microsoft Corporation. + * + * Author: + * Jake Oshins + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published + * by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for more + * details. + * + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* + * Protocol versions. The low word is the minor version, the high word the major + * version. + */ + +#define PCI_MAKE_VERSION(major, minor) ((__u32)(((major) << 16) | (major))) +#define PCI_MAJOR_VERSION(version) ((__u32)(version) >> 16) +#define PCI_MINOR_VERSION(version) ((__u32)(version) & 0xff) + +enum { + PCI_PROTOCOL_VERSION_1_1 = PCI_MAKE_VERSION(1, 1), + PCI_PROTOCOL_VERSION_CURRENT = PCI_PROTOCOL_VERSION_1_1 +}; + +#define PCI_CONFIG_MMIO_LENGTH 0x2000 +#define MAX_SUPPORTED_MSI_MESSAGES 0x400 + +/* + * Message Types + */ + +enum pci_message_type { + /* + * Version 1.1 + */ + PCI_MESSAGE_BASE = 0x42490000, + PCI_BUS_RELATIONS = PCI_MESSAGE_BASE + 0, + PCI_QUERY_BUS_RELATIONS = PCI_MESSAGE_BASE + 1, + PCI_POWER_STATE_CHANGE = PCI_MESSAGE_BASE + 4, + PCI_QUERY_RESOURCE_REQUIREMENTS = PCI_MESSAGE_BASE + 5, + PCI_QUERY_RESOURCE_RESOURCES = PCI_MESSAGE_BASE + 6, + PCI_BUS_D0ENTRY = PCI_MESSAGE_BASE + 7, + PCI_BUS_D0EXIT = PCI_MESSAGE_BASE + 8, + PCI_READ_BLOCK = PCI_MESSAGE_BASE + 9, + PCI_WRITE_BLOCK = PCI_MESSAGE_BASE + 0xA, + PCI_EJECT = PCI_MESSAGE_BASE + 0xB, + PCI_QUERY_STOP = PCI_MESSAGE_BASE + 0xC, + PCI_REENABLE = PCI_MESSAGE_BASE + 0xD, + PCI_QUERY_STOP_FAILED = PCI_MESSAGE_BASE + 0xE, + PCI_EJECTION_COMPLETE = PCI_MESSAGE_BASE + 0xF, + PCI_RESOURCES_ASSIGNED = PCI_MESSAGE_BASE + 0x10, + PCI_RESOURCES_RELEASED = PCI_MESSAGE_BASE + 0x11, + PCI_INVALIDATE_BLOCK = PCI_MESSAGE_BASE + 0x12, + PCI_QUERY_PROTOCOL_VERSION = PCI_MESSAGE_BASE + 0x13, + PCI_CREATE_INTERRUPT_MESSAGE = PCI_MESSAGE_BASE + 0x14, + PCI_DELETE_INTERRUPT_MESSAGE = PCI_MESSAGE_BASE + 0x15, + PCI_MESSAGE_MAXIMUM +}; + +/* + * Structures defining the virtual PCI Express protocol. + */ + +union pci_version { + struct { + __u16 minor_version; + __u16 major_version; + } parts; + __u32 version; +} __packed; + +/* + * Function numbers are 8-bits wide on Express, as interpreted through ARI, + * which is all this driver does. This representation is the one used in + * Windows, which is what is expected when sending this back and forth with + * the Hyper-V parent partition. + */ +union win_slot_encoding { + struct { + __u32 func:8; + __u32 reserved:24; + } bits; + __u32 slot; +} __packed; + +/* + * Pretty much as defined in the PCI Specifications. + */ +struct pci_function_description { + __u16 v_id; /* vendor ID */ + __u16 d_id; /* device ID */ + __u8 rev; + __u8 prog_intf; + __u8 subclass; + __u8 base_class; + __u32 subsystem_id; + union win_slot_encoding win_slot; + __u32 ser; /* serial number */ +} __packed; + +/** + * struct hv_msi_desc + * @vector: IDT entry + * @delivery_mode: As defined in Intel's Programmer's + * Reference Manual, Volume 3, Chapter 8. + * @vector_count: Number of contiguous entries in the + * Interrupt Descriptor Table that are + * occupied by this Message-Signaled + * Interrupt. For "MSI", as first defined + * in PCI 2.2, this can be between 1 and + * 32. For "MSI-X," as first defined in PCI + * 3.0, this must be 1, as each MSI-X table + * entry would have its own descriptor. + * @reserved: Empty space + * @cpu_mask: All the target virtual processors. + */ +struct hv_msi_desc { + __u8 vector; + __u8 delivery_mode; + __u16 vector_count; + __u32 reserved; + __u64 cpu_mask; +} __packed; + +/** + * struct tran_int_desc + * @reserved: unused, padding + * @vector_count: same as in hv_msi_desc + * @data: This is the "data payload" value that is + * written by the device when it generates + * a message-signaled interrupt, either MSI + * or MSI-X. + * @address: This is the address to which the data + * payload is written on interrupt + * generation. + */ +struct tran_int_desc { + __u16 reserved; + __u16 vector_count; + __u32 data; + __u64 address; +} __packed; + +/* + * A generic message format for virtual PCI. + * Specific message formats are defined later in the file. + */ + +struct pci_message { + __u32 message_type; +} __packed; + +struct pci_child_message { + __u32 message_type; + union win_slot_encoding wslot; +} __packed; + +struct pci_incoming_message { + struct vmpacket_descriptor hdr; + struct pci_message message_type; +} __packed; + +struct pci_response { + struct vmpacket_descriptor hdr; + __s32 status; /* negative values are failures*/ +} __packed; + +struct pci_packet { + void (*completion_func)(void *context, struct pci_response *resp, + int resp_packet_size); + void *compl_ctxt; + struct pci_message message; +}; + +/* + * Specific message types supporting the PCI protocol. + */ + +/* + * Version negotiation message. Sent from the guest to the host. + * The guest is free to try different versions until the host + * accepts the version. + * + * pci_version: The protocol version requested. + * is_last_attempt: If TRUE, this is the last version guest will request. + * reservedz: Reserved field, set to zero. + */ + +struct pci_version_request { + struct pci_message message_type; + enum pci_message_type protocol_version; +} __packed; + +/* + * Bus D0 Entry. This is sent from the guest to the host when the virtual + * bus (PCI Express port) is ready for action. + */ + +struct pci_bus_d0_entry { + struct pci_message message_type; + __u32 reserved; + __u64 mmio_base; +} __packed; + +struct pci_bus_relations { + struct pci_incoming_message incoming; + __u32 device_count; + struct pci_function_description func[1]; +} __packed; + +struct pci_q_res_req_response { + struct vmpacket_descriptor hdr; + __s32 status; /* negative values are failures*/ + __u32 probed_bar[6]; +} __packed; + +struct pci_set_power { + struct pci_message message_type; + union win_slot_encoding wslot; + __u32 power_state; /* In Windows terms */ + __u32 reserved; +} __packed; + +struct pci_set_power_response { + struct vmpacket_descriptor hdr; + __s32 status; /* negative values are failures*/ + union win_slot_encoding wslot; + __u32 resultant_state; /* In Windows terms */ + __u32 reserved; +} __packed; + +struct pci_resources_assigned { + struct pci_message message_type; + union win_slot_encoding wslot; + u8 memory_range[0x14][6]; /* not used here */ + u32 msi_descriptors; + u32 reserved[4]; +} __packed; + +struct pci_create_interrupt { + struct pci_message message_type; + union win_slot_encoding wslot; + struct hv_msi_desc int_desc; +} __packed; + +struct pci_create_int_response { + struct pci_response response; + u32 reserved; + struct tran_int_desc int_desc; +} __packed; + +struct pci_delete_interrupt { + struct pci_message message_type; + union win_slot_encoding wslot; + struct tran_int_desc int_desc; +} __packed; + +struct pci_dev_incoming { + struct pci_incoming_message incoming; + union win_slot_encoding wslot; +} __packed; + +struct pci_eject_response { + u32 message_type; + union win_slot_encoding wslot; + u32 status; +} __packed; + +static int pci_ring_size = (4 * PAGE_SIZE); + +/* + * Definitions or interrupt steering hypercall. + */ +#define HV_PARTITION_ID_SELF ((u64)-1) +#define HVCALL_RETARGET_INTERRUPT 0x7e + +struct retarget_msi_interrupt { + u64 partition_id; /* use "self" */ + u64 device_id; + u32 source; /* 1 for MSI(-X) */ + u32 reserved1; + u32 address; + u32 data; + u64 reserved2; + u32 vector; + u32 flags; + u64 vp_mask; +} __packed; + +/* + * Driver specific state. + */ + +enum hv_pcibus_state { + hv_pcibus_init = 0, + hv_pcibus_probed, + hv_pcibus_installed, + hv_pcibus_maximum +}; + +struct hv_pcibus_device { + struct pci_sysdata sysdata; + enum hv_pcibus_state state; + atomic_t remove_lock; + struct hv_device *hdev; + resource_size_t low_mmio_space; + resource_size_t high_mmio_space; + struct resource *mem_config; + struct resource *low_mmio_res; + struct resource *high_mmio_res; + struct completion *survey_event; + struct completion remove_event; + struct pci_bus *pci_bus; + spinlock_t config_lock; /* Avoids two threads writing index page */ + spinlock_t device_list_lock; /* Protects lists below */ + void __iomem *cfg_addr; + + struct semaphore enum_sem; + struct list_head resources_for_children; + + struct list_head children; + struct list_head dr_list; + struct work_struct wrk; + + struct msi_domain_info msi_info; + struct msi_controller msi_chip; + struct irq_domain *irq_domain; +}; + +/* + * Tracks "Device Relations" messages from the host, which must be both + * processed in order and deferred so that they don't run in the context + * of the incoming packet callback. + */ +struct hv_dr_work { + struct work_struct wrk; + struct hv_pcibus_device *bus; +}; + +struct hv_dr_state { + struct list_head list_entry; + __u32 device_count; + struct pci_function_description func[1]; +}; + +enum hv_pcichild_state { + hv_pcichild_init = 0, + hv_pcichild_requirements, + hv_pcichild_resourced, + hv_pcichild_ejecting, + hv_pcichild_maximum +}; + +enum hv_pcidev_ref_reason { + hv_pcidev_ref_invalid = 0, + hv_pcidev_ref_initial, + hv_pcidev_ref_by_slot, + hv_pcidev_ref_packet, + hv_pcidev_ref_pnp, + hv_pcidev_ref_childlist, + hv_pcidev_irqdata, + hv_pcidev_ref_max +}; + +static char *hv_pcidev_ref_debug[hv_pcidev_ref_max] = { + "hv_pcidev_ref_invalid", + "hv_pcidev_ref_initial", + "hv_pcidev_ref_by_slot", + "hv_pcidev_ref_packet", + "hv_pcidev_ref_pnp", + "hv_pcidev_ref_childlist", + "hv_pcidev_irqdata" +}; + +struct hv_pci_dev { + /* List protected by pci_rescan_remove_lock */ + struct list_head list_entry; + atomic_t refs; + enum hv_pcichild_state state; + struct pci_function_description desc; + bool reported_missing; + struct hv_pcibus_device *hbus; + struct work_struct wrk; + + /* + * What would be observed if one wrote 0xFFFFFFFF to a BAR and then + * read it back, for each of the BAR offsets within config space. + */ + u32 probed_bar[6]; +}; + +struct hv_pci_compl { + struct completion host_event; + __s32 completion_status; +}; + +/** + * hv_pci_generic_compl() - Invoked for a completion packet + * @context: Set up by the sender of the packet. + * @resp: The response packet + * @resp_packet_size: Size in bytes of the packet + * + * This function is used to trigger an event and report status + * for any message for which the completion packet contains a + * status and nothing else. + */ +static +void +hv_pci_generic_compl(void *context, struct pci_response *resp, + int resp_packet_size) +{ + struct hv_pci_compl *comp_pkt = context; + + if (resp_packet_size >= offsetofend(struct pci_response, status)) + comp_pkt->completion_status = resp->status; + complete(&comp_pkt->host_event); +} + +static struct hv_pci_dev *lookup_hv_dev(struct hv_pcibus_device *hbus, + u32 wslot); +static void hv_pcichild_inc(struct hv_pci_dev *hv_pcidev, + enum hv_pcidev_ref_reason reason); +static void hv_pcichild_dec(struct hv_pci_dev *hv_pcidev, + enum hv_pcidev_ref_reason reason); + +static void hv_pcibus_inc(struct hv_pcibus_device *hv_pcibus); +static void hv_pcibus_dec(struct hv_pcibus_device *hv_pcibus); + +/** + * devfn_to_wslot() - Convert from Linux PCI slot to Windows + * @devfn: The Linux representation of PCI slot + * + * Windows uses a slightly different representation of PCI slot. + * + * Return: The Windows representation + */ +static u32 devfn_to_wslot(int devfn) +{ + union win_slot_encoding wslot; + + wslot.slot = 0; + wslot.bits.func = PCI_SLOT(devfn) | (PCI_FUNC(devfn) << 5); + + return wslot.slot; +} + +/** + * wslot_to_devfn() - Convert from Windows PCI slot to Linux + * @wslot: The Windows representation of PCI slot + * + * Windows uses a slightly different representation of PCI slot. + * + * Return: The Linux representation + */ +static int wslot_to_devfn(u32 wslot) +{ + union win_slot_encoding slot_no; + + slot_no.slot = wslot; + return PCI_DEVFN(0, slot_no.bits.func); +} + +/** + * _hv_pcifront_read_config() - Internal PCI config read + * @hpdev: The PCI driver's representation of the device + * @where: Offset within config space + * @size: Size of the transfer + * @val: Pointer to the buffer receiving the data + */ +static void _hv_pcifront_read_config(struct hv_pci_dev *hpdev, int where, + int size, u32 *val) +{ + unsigned long flags; + void __iomem *addr = hpdev->hbus->cfg_addr + 0x1000 + where; + + /* + * If the attempt is to read the IDs or the ROM BAR, simulate that. + */ + if (where + size <= PCI_COMMAND) { + memcpy(val, ((u8 *)&hpdev->desc.v_id) + where, size); + } else if (where >= PCI_CLASS_REVISION && where + size <= + PCI_CACHE_LINE_SIZE) { + memcpy(val, ((u8 *)&hpdev->desc.rev) + where - + PCI_CLASS_REVISION, size); + } else if (where >= PCI_SUBSYSTEM_VENDOR_ID && where + size <= + PCI_ROM_ADDRESS) { + memcpy(val, (u8 *)&hpdev->desc.subsystem_id + where - + PCI_SUBSYSTEM_VENDOR_ID, size); + } else if (where >= PCI_ROM_ADDRESS && where + size <= + PCI_CAPABILITY_LIST) { + /* ROM BARs are unimplemented */ + *val = 0; + } else if (where >= PCI_INTERRUPT_LINE && where + size <= + PCI_INTERRUPT_PIN) { + /* + * Interrupt Line and Interrupt PIN are hard-wired to zero + * because this front-end only supports message-signaled + * interrupts. + */ + *val = 0; + } else { + spin_lock_irqsave(&hpdev->hbus->config_lock, flags); + writel(hpdev->desc.win_slot.slot, hpdev->hbus->cfg_addr); + switch (size) { + case 1: + *val = readb(addr); + break; + case 2: + *val = readw(addr); + break; + default: + *val = readl(addr); + break; + } + spin_unlock_irqrestore(&hpdev->hbus->config_lock, flags); + } +} + +/** + * _hv_pcifront_write_config() - Internal PCI config write + * @hpdev: The PCI driver's representation of the device + * @where: Offset within config space + * @size: Size of the transfer + * @val: The data being transferred + */ +static void _hv_pcifront_write_config(struct hv_pci_dev *hpdev, int where, + int size, u32 val) +{ + unsigned long flags; + void __iomem *addr = hpdev->hbus->cfg_addr + 0x1000 + where; + + if (where >= PCI_SUBSYSTEM_VENDOR_ID && + where + size <= PCI_CAPABILITY_LIST) { + /* SSIDs and ROM BARs are read-only */ + } else if (where >= PCI_COMMAND) { + spin_lock_irqsave(&hpdev->hbus->config_lock, flags); + writel(hpdev->desc.win_slot.slot, hpdev->hbus->cfg_addr); + switch (size) { + case 1: + writeb(val, addr); + break; + case 2: + writew(val, addr); + break; + default: + writel(val, addr); + break; + } + spin_unlock_irqrestore(&hpdev->hbus->config_lock, flags); + } +} + +/** + * hv_pcifront_read_config() - Read configuration space + * @bus: PCI Bus structure + * @devfn: Device/function + * @where: Offset from base + * @size: Byte/word/dword + * @val: Value to be read + * + * Return: PCIBIOS_SUCCESSFUL on success + * PCIBIOS_DEVICE_NOT_FOUND on failure + */ +static int hv_pcifront_read_config(struct pci_bus *bus, unsigned int devfn, + int where, int size, u32 *val) +{ + struct hv_pcibus_device *hbus = + container_of(bus->sysdata, struct hv_pcibus_device, sysdata); + struct hv_pci_dev *hpdev; + + hpdev = lookup_hv_dev(hbus, devfn_to_wslot(devfn)); + if (!hpdev) + return PCIBIOS_DEVICE_NOT_FOUND; + + _hv_pcifront_read_config(hpdev, where, size, val); + + hv_pcichild_dec(hpdev, hv_pcidev_ref_by_slot); + return PCIBIOS_SUCCESSFUL; +} + +/** + * hv_pcifront_write_config() - Write configuration space + * @bus: PCI Bus structure + * @devfn: Device/function + * @where: Offset from base + * @size: Byte/word/dword + * @val: Value to be written to device + * + * Return: PCIBIOS_SUCCESSFUL on success + * PCIBIOS_DEVICE_NOT_FOUND on failure + */ +static int hv_pcifront_write_config(struct pci_bus *bus, unsigned int devfn, + int where, int size, u32 val) +{ + struct hv_pcibus_device *hbus = + container_of(bus->sysdata, struct hv_pcibus_device, sysdata); + struct hv_pci_dev *hpdev; + + hpdev = lookup_hv_dev(hbus, devfn_to_wslot(devfn)); + if (!hpdev) + return PCIBIOS_DEVICE_NOT_FOUND; + + _hv_pcifront_write_config(hpdev, where, size, val); + + hv_pcichild_dec(hpdev, hv_pcidev_ref_by_slot); + return PCIBIOS_SUCCESSFUL; +} + +/* PCIe operations */ +static struct pci_ops hv_pcifront_ops = { + .read = hv_pcifront_read_config, + .write = hv_pcifront_write_config, +}; + +/* Interrupt management hooks */ + +/** + * hv_msi_free() - Free the MSI. + * @domain: The interrupt domain pointer + * @info: Extra MSI-related context + * @irq: Identifies the IRQ. + * + * The Hyper-V parent partition and hypervisor are tracking the + * messages that are in use, keeping the interrupt redirection + * table up to date. This callback sends a message that frees + * the the IRT entry and related tracking nonsense. + */ +static void hv_msi_free(struct irq_domain *domain, struct msi_domain_info *info, + unsigned int irq) +{ + struct pci_delete_interrupt *int_pkt; + struct { + struct pci_packet pkt; + u8 buffer[sizeof(struct pci_delete_interrupt) - + sizeof(struct pci_message)]; + } ctxt; + struct hv_pcibus_device *hbus; + struct hv_pci_dev *hpdev; + struct irq_desc *desc; + struct msi_desc *msi; + struct tran_int_desc *int_desc; + struct pci_dev *pdev; + + desc = irq_to_desc(irq); + msi = irq_desc_get_msi_desc(desc); + pdev = msi_desc_to_pci_dev(msi); + hbus = info->data; + hpdev = lookup_hv_dev(hbus, devfn_to_wslot(pdev->devfn)); + if (!hpdev) + return; + + int_desc = irq_get_chip_data(irq); + if (int_desc) { + memset(&ctxt, 0, sizeof(ctxt)); + int_pkt = (struct pci_delete_interrupt *)&ctxt.pkt.message; + int_pkt->message_type.message_type = + PCI_DELETE_INTERRUPT_MESSAGE; + int_pkt->wslot.slot = hpdev->desc.win_slot.slot; + int_pkt->int_desc = *int_desc; + vmbus_sendpacket(hbus->hdev->channel, int_pkt, sizeof(*int_pkt), + (unsigned long)&ctxt.pkt, VM_PKT_DATA_INBAND, + 0); + desc->irq_data.chip_data = NULL; + kfree(int_desc); + } + + hv_pcichild_dec(hpdev, hv_pcidev_ref_by_slot); +} + +static int hv_set_affinity(struct irq_data *data, const struct cpumask *dest, + bool force) +{ + struct irq_data *parent = data->parent_data; + + return parent->chip->irq_set_affinity(parent, dest, force); +} + +void hv_irq_mask(struct irq_data *data) +{ + pci_msi_mask_irq(data); +} + +/** + * hv_irq_unmask() - "Unmask" the IRQ by setting its current + * affinity. + * @data: Describes the IRQ + * + * Build new a destination for the MSI and make a hypercall to + * update the Interrupt Redirection Table. "Device Logical ID" + * is built out of this PCI bus's instance GUID and the function + * number of the device. + */ +void hv_irq_unmask(struct irq_data *data) +{ + struct msi_desc *msi_desc = irq_data_get_msi_desc(data); + struct irq_cfg *cfg = irqd_cfg(data); + struct retarget_msi_interrupt params; + struct hv_pcibus_device *hbus; + struct cpumask *dest; + struct pci_bus *pbus; + struct pci_dev *pdev; + int cpu; + + dest = irq_data_get_affinity_mask(data); + pdev = msi_desc_to_pci_dev(msi_desc); + pbus = pdev->bus; + hbus = container_of(pbus->sysdata, struct hv_pcibus_device, sysdata); + + memset(¶ms, 0, sizeof(params)); + params.partition_id = HV_PARTITION_ID_SELF; + params.source = 1; /* MSI(-X) */ + params.address = msi_desc->msg.address_lo; + params.data = msi_desc->msg.data; + params.device_id = (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.vector = cfg->vector; + + for_each_cpu_and(cpu, dest, cpu_online_mask) + params.vp_mask |= (1 << vmbus_cpu_number_to_vp_number(cpu)); + + hv_do_hypercall(HVCALL_RETARGET_INTERRUPT, ¶ms, NULL); + + pci_msi_unmask_irq(data); +} + +struct compose_comp_ctxt { + struct hv_pci_compl comp_pkt; + struct tran_int_desc int_desc; +}; + +static void hv_pci_compose_compl(void *context, struct pci_response *resp, + int resp_packet_size) +{ + struct compose_comp_ctxt *comp_pkt = context; + struct pci_create_int_response *int_resp = + (struct pci_create_int_response *)resp; + + comp_pkt->comp_pkt.completion_status = resp->status; + comp_pkt->int_desc = int_resp->int_desc; + complete(&comp_pkt->comp_pkt.host_event); +} + +/** + * hv_compose_msi_msg() - Supplies a valid MSI address/data + * @data: Everything about this MSI + * @msg: Buffer that is filled in by this function + * + * This function unpacks the IRQ looking for target CPU set, IDT + * vector and mode and sends a message to the parent partition + * asking for a mapping for that tuple in this partition. The + * 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) +{ + struct irq_cfg *cfg = irqd_cfg(data); + struct hv_pcibus_device *hbus; + struct hv_pci_dev *hpdev; + struct pci_bus *pbus; + struct pci_dev *pdev; + struct pci_create_interrupt *int_pkt; + struct compose_comp_ctxt comp; + struct tran_int_desc *int_desc; + struct cpumask *affinity; + struct { + struct pci_packet pkt; + u8 buffer[sizeof(struct pci_create_interrupt) - + sizeof(struct pci_message)]; + } ctxt; + int cpu; + int ret; + + pdev = msi_desc_to_pci_dev(irq_data_get_msi_desc(data)); + pbus = pdev->bus; + hbus = container_of(pbus->sysdata, struct hv_pcibus_device, sysdata); + hpdev = lookup_hv_dev(hbus, devfn_to_wslot(pdev->devfn)); + + if (!hpdev) + goto return_null_message; + + int_desc = kzalloc(sizeof(*int_desc), GFP_KERNEL); + if (!int_desc) + goto drop_reference; + + memset(&ctxt, 0, sizeof(ctxt)); + init_completion(&comp.comp_pkt.host_event); + ctxt.pkt.completion_func = hv_pci_compose_compl; + ctxt.pkt.compl_ctxt = ∁ + int_pkt = (struct pci_create_interrupt *)&ctxt.pkt.message; + int_pkt->message_type.message_type = PCI_CREATE_INTERRUPT_MESSAGE; + int_pkt->wslot.slot = hpdev->desc.win_slot.slot; + int_pkt->int_desc.vector = cfg->vector; + int_pkt->int_desc.vector_count = 1; + int_pkt->int_desc.delivery_mode = + (apic->irq_delivery_mode == dest_LowestPrio) ? 1 : 0; + + /* + * This bit doesn't have to work on machines with more than 64 + * processors because Hyper-V only supports 64 in a guest. + */ + affinity = irq_data_get_affinity_mask(data); + for_each_cpu(cpu, affinity) { + if (cpu_is_offline(cpu)) + continue; + int_pkt->int_desc.cpu_mask |= + (1 << vmbus_cpu_number_to_vp_number(cpu)); + } + + ret = vmbus_sendpacket(hpdev->hbus->hdev->channel, int_pkt, + sizeof(*int_pkt), (unsigned long)&ctxt.pkt, + VM_PKT_DATA_INBAND, + VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED); + if (!ret) + wait_for_completion(&comp.comp_pkt.host_event); + + if (comp.comp_pkt.completion_status < 0) { + pr_err("Request for interrupt failed: 0x%x", + comp.comp_pkt.completion_status); + goto free_int_desc; + } + + /* + * Record the assignment so that this can be unwound later. Using + * irq_set_chip_data() here would be appropriate, but the lock it takes + * is already held. + */ + *int_desc = comp.int_desc; + data->chip_data = int_desc; + + /* Pass up the result. */ + msg->address_hi = comp.int_desc.address >> 32; + msg->address_lo = comp.int_desc.address & 0xffffffff; + msg->data = comp.int_desc.data; + + hv_pcichild_dec(hpdev, hv_pcidev_ref_by_slot); + return; + +free_int_desc: + kfree(int_desc); +drop_reference: + hv_pcichild_dec(hpdev, hv_pcidev_ref_by_slot); +return_null_message: + msg->address_hi = 0; + msg->address_lo = 0; + msg->data = 0; +} + +/* HW Interrupt Chip Descriptor */ +static struct irq_chip hv_msi_irq_chip = { + .name = "Hyper-V PCIe MSI", + .irq_compose_msi_msg = hv_compose_msi_msg, + .irq_set_affinity = hv_set_affinity, + .irq_ack = irq_chip_ack_parent, + .irq_mask = hv_irq_mask, + .irq_unmask = hv_irq_unmask, +}; + +static irq_hw_number_t hv_msi_domain_ops_get_hwirq(struct msi_domain_info *info, + msi_alloc_info_t *arg) +{ + return arg->msi_hwirq; +} + +/** + * hv_msi_set_desc() - Create a "hardware IRQ" for a message. + * @arg: Describes the device + * @desc: Describes the interrupt + * + * This function is derived from pci_msi_set_desc(), which + * creates a "hardware IRQ" based on the segment, bus, device, + * function and message numbers. Here, the bus and device + * numbers will always be zero. So, in the interest of more + * entropy, more of the bits in msi_hwirq are derived from + * things which will be non-zero. + */ +static void hv_msi_set_desc(msi_alloc_info_t *arg, struct msi_desc *desc) +{ + arg->msi_hwirq = (irq_hw_number_t)desc->msi_attrib.entry_nr | + (arg->msi_dev->devfn << 11) | + (pci_domain_nr(arg->msi_dev->bus) & 0xFFFFFFFF) << 19; +} + +static struct msi_domain_ops hv_msi_ops = { + .get_hwirq = hv_msi_domain_ops_get_hwirq, + .msi_prepare = pci_msi_prepare, + .set_desc = hv_msi_set_desc, + .msi_free = hv_msi_free, +}; + +/** + * hv_pcie_free_irq_domain - Free IRQ domain + * @hbus: The root PCI bus + */ +static void hv_pcie_free_irq_domain(struct hv_pcibus_device *hbus) +{ + u32 irq; + int i; + + for (i = 0; i < MAX_SUPPORTED_MSI_MESSAGES; i++) { + irq = irq_find_mapping(hbus->irq_domain, i); + if (irq > 0) + irq_dispose_mapping(irq); + } + + irq_domain_remove(hbus->irq_domain); +} + +/** + * hv_pcie_init_irq_domain() - Initialize IRQ domain + * @hbus: The root PCI bus + * + * This function creates an IRQ domain which will be used for + * interrupts from devices that have been passed through. These + * devices only support MSI and MSI-X, not line-based interrupts + * or simulations of line-based interrupts through PCIe's + * fabric-layer messages. Because interrupts are remapped, we + * can support multi-message MSI here. + * + * Return: '0' on success and error value on failure + */ +static int hv_pcie_init_irq_domain(struct hv_pcibus_device *hbus) +{ + hbus->msi_info.chip = &hv_msi_irq_chip; + hbus->msi_info.chip_data = hbus; + hbus->msi_info.ops = &hv_msi_ops; + hbus->msi_info.flags = (MSI_FLAG_USE_DEF_DOM_OPS | + MSI_FLAG_USE_DEF_CHIP_OPS | MSI_FLAG_MULTI_PCI_MSI | + MSI_FLAG_PCI_MSIX); + hbus->msi_info.handler = handle_edge_irq; + hbus->msi_info.handler_name = "edge"; + hbus->msi_info.data = hbus; + hbus->irq_domain = pci_msi_create_irq_domain(hbus->sysdata.fwnode, + &hbus->msi_info, + x86_vector_domain); + if (!hbus->irq_domain) { + pr_err("Failed to build an MSI IRQ domain\n"); + return -ENODEV; + } + + return 0; +} + +/** + * get_bar_size() - Get the address space consumed by a BAR + * @bar_val: Value that a BAR returned after -1 was written + * 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 + * table entry that maps the BAR into the VM can't specify an + * offset within a page. The invariant is that the hypervisor + * must place any BARs of smaller than page length at the + * beginning of a page. + * + * Return: Size in bytes of the consumed MMIO space. + */ +static u64 get_bar_size(u64 bar_val) +{ + return round_up((1 + ~(bar_val & PCI_BASE_ADDRESS_MEM_MASK)), + PAGE_SIZE); +} + +/** + * survey_child_resources() - Total all MMIO requirements + * @hbus: Root PCI bus, as understood by this driver + */ +static void survey_child_resources(struct hv_pcibus_device *hbus) +{ + struct list_head *iter; + struct hv_pci_dev *hpdev; + resource_size_t bar_size = 0; + unsigned long flags; + struct completion *event; + u64 bar_val; + int i; + + /* If nobody is waiting on the answer, don't compute it. */ + event = xchg(&hbus->survey_event, NULL); + if (!event) + return; + + /* If the answer has already been computed, go with it. */ + if (hbus->low_mmio_space || hbus->high_mmio_space) { + complete(event); + return; + } + + spin_lock_irqsave(&hbus->device_list_lock, flags); + + /* + * Due to an interesting quirk of the PCI spec, all memory regions + * for a child device are a power of 2 in size and aligned in memory, + * so it's sufficient to just add them up without tracking alignment. + */ + list_for_each(iter, &hbus->children) { + hpdev = container_of(iter, struct hv_pci_dev, list_entry); + for (i = 0; i < 6; i++) { + if (hpdev->probed_bar[i] & PCI_BASE_ADDRESS_SPACE_IO) + pr_err("There's an I/O BAR in this list!\n"); + + if (hpdev->probed_bar[i] != 0) { + /* + * A probed BAR has all the upper bits set that + * can be changed. + */ + + bar_val = hpdev->probed_bar[i]; + if (bar_val & PCI_BASE_ADDRESS_MEM_TYPE_64) + bar_val |= + ((u64)hpdev->probed_bar[++i] << 32); + else + bar_val |= 0xffffffff00000000ULL; + + bar_size = get_bar_size(bar_val); + + if (bar_val & PCI_BASE_ADDRESS_MEM_TYPE_64) + hbus->high_mmio_space += bar_size; + else + hbus->low_mmio_space += bar_size; + } + } + } + + spin_unlock_irqrestore(&hbus->device_list_lock, flags); + complete(event); +} + +/** + * prepopulate_bars() - Fill in BARs with defaults + * @hbus: Root PCI bus, as understood by this driver + * + * The core PCI driver code seems much, much happier if the BARs + * for a device have values upon first scan. So fill them in. + * The algorithm below works down from large sizes to small, + * attempting to pack the assignments optimally. The assumption, + * enforced in other parts of the code, is that the beginning of + * the memory-mapped I/O space will be aligned on the largest + * BAR size. + */ +static void prepopulate_bars(struct hv_pcibus_device *hbus) +{ + resource_size_t high_size = 0; + resource_size_t low_size = 0; + resource_size_t high_base = 0; + resource_size_t low_base = 0; + resource_size_t bar_size; + struct hv_pci_dev *hpdev; + struct list_head *iter; + unsigned long flags; + u64 bar_val; + u32 command; + bool high; + int i; + + if (hbus->low_mmio_space) { + low_size = 1 << (63 - __builtin_clzll(hbus->low_mmio_space)); + low_base = hbus->low_mmio_res->start; + } + + if (hbus->high_mmio_space) { + high_size = 1 << (63 - __builtin_clzll(hbus->high_mmio_space)); + high_base = hbus->high_mmio_res->start; + } + + spin_lock_irqsave(&hbus->device_list_lock, flags); + + /* Pick addresses for the BARs. */ + do { + list_for_each(iter, &hbus->children) { + hpdev = container_of(iter, struct hv_pci_dev, + list_entry); + for (i = 0; i < 6; i++) { + bar_val = hpdev->probed_bar[i]; + if (bar_val == 0) + continue; + high = bar_val & PCI_BASE_ADDRESS_MEM_TYPE_64; + if (high) { + bar_val |= + ((u64)hpdev->probed_bar[i + 1] + << 32); + } else { + bar_val |= 0xffffffffULL << 32; + } + bar_size = get_bar_size(bar_val); + if (high) { + if (high_size != bar_size) { + i++; + continue; + } + _hv_pcifront_write_config(hpdev, + PCI_BASE_ADDRESS_0 + (4 * i), + 4, + (u32)(high_base & 0xffffff00)); + _hv_pcifront_write_config(hpdev, + PCI_BASE_ADDRESS_0 + + (4 * (i + 1)), 4, + (u32)(high_base >> 32)); + high_base += bar_size; + } else { + if (low_size != bar_size) + continue; + _hv_pcifront_write_config(hpdev, + PCI_BASE_ADDRESS_0 + (4 * i), + 4, + (u32)(low_base & 0xffffff00)); + low_base += bar_size; + } + } + if (high_size <= 1 && low_size <= 1) { + /* Set the memory enable bit. */ + _hv_pcifront_read_config(hpdev, PCI_COMMAND, 2, + &command); + command |= PCI_COMMAND_MEMORY; + _hv_pcifront_write_config(hpdev, PCI_COMMAND, 2, + command); + break; + } + } + + high_size >>= 1; + low_size >>= 1; + } while (high_size || low_size); + + spin_unlock_irqrestore(&hbus->device_list_lock, flags); +} + +/** + * create_root_hv_pci_bus() - Expose a new root PCI bus + * @hbus: Root PCI bus, as understood by this driver + * + * Return: 0 on success, -errno on failure + */ +static int create_root_hv_pci_bus(struct hv_pcibus_device *hbus) +{ + /* Register the device */ + hbus->pci_bus = pci_create_root_bus(&hbus->hdev->device, + 0, /* bus number is always zero */ + &hv_pcifront_ops, + &hbus->sysdata, + &hbus->resources_for_children); + if (!hbus->pci_bus) + return -ENODEV; + + hbus->pci_bus->msi = &hbus->msi_chip; + hbus->pci_bus->msi->dev = &hbus->hdev->device; + + pci_scan_child_bus(hbus->pci_bus); + pci_bus_assign_resources(hbus->pci_bus); + pci_bus_add_devices(hbus->pci_bus); + hbus->state = hv_pcibus_installed; + return 0; +} + +struct q_res_req_compl { + struct completion host_event; + struct hv_pci_dev *hpdev; +}; + +/** + * q_resource_requirements() - Query Resource Requirements + * @context: The completion context. + * @resp: The respose that came from the host. + * @resp_packet_size: The size in bytes of resp. + * + * This function is invoked on completion of a Query Resource + * Requirements packet. + */ +static void q_resource_requirements(void *context, struct pci_response *resp, + int resp_packet_size) +{ + struct q_res_req_compl *completion = context; + struct pci_q_res_req_response *q_res_req = + (struct pci_q_res_req_response *)resp; + int i; + + if (resp->status < 0) { + pr_err("query resource requirements failed: %x\n", + resp->status); + } else { + for (i = 0; i < 6; i++) { + completion->hpdev->probed_bar[i] = + q_res_req->probed_bar[i]; + } + } + + complete(&completion->host_event); +} + +static void hv_pcichild_inc(struct hv_pci_dev *hpdev, + enum hv_pcidev_ref_reason reason) +{ + pr_devel("+%s %p\n", hv_pcidev_ref_debug[reason], hpdev); + atomic_inc(&hpdev->refs); +} + +static void hv_pcichild_dec(struct hv_pci_dev *hpdev, + enum hv_pcidev_ref_reason reason) +{ + pr_devel("-%s %p\n", hv_pcidev_ref_debug[reason], hpdev); + if (atomic_dec_and_test(&hpdev->refs)) { + pr_devel("Freeing hv_pcidev %p\n", hpdev); + kfree(hpdev); + } +} + +/** + * 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. + * + * This function creates the tracking structure for a new child + * device and kicks off the process of figuring out what it is. + * + * Return: Pointer to the new tracking struct + */ +static +struct hv_pci_dev * +new_pcichild_device(struct hv_pcibus_device *hbus, + struct pci_function_description *desc) +{ + struct hv_pci_dev *hpdev; + struct pci_child_message *res_req; + struct q_res_req_compl comp_pkt; + union { + struct pci_packet init_packet; + __u8 buffer[0x100]; + } pkt; + unsigned long flags; + int ret; + + hpdev = kzalloc(sizeof(*hpdev), GFP_ATOMIC); + if (!hpdev) + return NULL; + + pr_devel("New child device (%p) reported (%04x:%04x) in slot %x.\n", + hpdev, desc->v_id, desc->d_id, desc->win_slot.slot); + + hpdev->hbus = hbus; + + memset(&pkt, 0, sizeof(pkt)); + init_completion(&comp_pkt.host_event); + comp_pkt.hpdev = hpdev; + pkt.init_packet.compl_ctxt = &comp_pkt; + pkt.init_packet.completion_func = q_resource_requirements; + res_req = (struct pci_child_message *)&pkt.init_packet.message; + res_req->message_type = PCI_QUERY_RESOURCE_REQUIREMENTS; + res_req->wslot.slot = desc->win_slot.slot; + + ret = vmbus_sendpacket(hbus->hdev->channel, res_req, + sizeof(struct pci_child_message), + (unsigned long)&pkt.init_packet, + VM_PKT_DATA_INBAND, + VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED); + if (ret) + goto error; + + wait_for_completion(&comp_pkt.host_event); + + hpdev->desc = *desc; + hv_pcichild_inc(hpdev, hv_pcidev_ref_initial); + hv_pcichild_inc(hpdev, hv_pcidev_ref_childlist); + spin_lock_irqsave(&hbus->device_list_lock, flags); + list_add_tail(&hpdev->list_entry, &hbus->children); + spin_unlock_irqrestore(&hbus->device_list_lock, flags); + return hpdev; + +error: + + kfree(hpdev); + return NULL; +} + +/** + * lookup_hv_dev() - Find device from slot + * @hbus: Root PCI bus, as understood by this driver + * @wslot: Location on the bus + * + * This function looks up a PCI device and returns in the + * internal representation of it. It leaves a reference on it, + * so that the device won't be deleted while somebody is using + * it. The caller is responsible for dropping this reference. + * + * Return: Internal representation of a PCI device + */ +static struct hv_pci_dev *lookup_hv_dev(struct hv_pcibus_device *hbus, + u32 wslot) +{ + unsigned long flags; + struct hv_pci_dev *iter, *hpdev = NULL; + + spin_lock_irqsave(&hbus->device_list_lock, flags); + list_for_each_entry(iter, &hbus->children, list_entry) { + if (iter->desc.win_slot.slot == wslot) { + hpdev = iter; + hv_pcichild_inc(hpdev, hv_pcidev_ref_by_slot); + break; + } + } + spin_unlock_irqrestore(&hbus->device_list_lock, flags); + + return hpdev; +} + +/** + * pci_devices_present_work() - Handle new list of child devices + * @work: Work struct embedded in struct hv_dr_work + * + * "Bus Relations" is the Windows term for "children of this + * bus." The terminology is preserved here for people trying to + * debug the interaction between Hyper-V and Linux. This + * function is called when the parent partition reports a list + * of functions that should be observed under this PCI Express + * port (bus). + * + * This function updates the list, and must tolerate being + * called multiple times with the same information. The typical + * number of child devices is one, with very atypical cases + * involving three or four, so the algorithms used here can be + * simple and inefficient. + * + * It must also treat the omission of a previously observed device as + * notification that the device no longer exists. + * + * Note that this function is a work item, and it may not be + * invoked in the order that it was queued. Back to back + * updates of the list of present devices may involve queuing + * mulitple work items, and this one may run before ones that + * were sent later. As such, this function only does something + * if is the last one in the queue. + */ +static void pci_devices_present_work(struct work_struct *work) +{ + u32 child_no; + bool found; + struct list_head *iter; + struct pci_function_description *new_desc; + struct hv_pci_dev *hpdev; + struct hv_pcibus_device *hbus; + struct list_head removed; + struct hv_dr_work *dr_wrk; + struct hv_dr_state *dr = NULL; + unsigned long flags; + + dr_wrk = container_of(work, struct hv_dr_work, wrk); + hbus = dr_wrk->bus; + kfree(dr_wrk); + + INIT_LIST_HEAD(&removed); + + if (down_interruptible(&hbus->enum_sem)) { + hv_pcibus_dec(hbus); + return; + } + + /* Pull this off the queue and process it if it was the last one. */ + spin_lock_irqsave(&hbus->device_list_lock, flags); + while (!list_empty(&hbus->dr_list)) { + dr = list_first_entry(&hbus->dr_list, struct hv_dr_state, + list_entry); + list_del(&dr->list_entry); + + /* Throw this away if the list still has stuff in it. */ + if (!list_empty(&hbus->dr_list)) { + kfree(dr); + continue; + } + } + spin_unlock_irqrestore(&hbus->device_list_lock, flags); + + if (!dr) { + up(&hbus->enum_sem); + hv_pcibus_dec(hbus); + return; + } + + /* First, mark all existing children as reported missing. */ + spin_lock_irqsave(&hbus->device_list_lock, flags); + list_for_each(iter, &hbus->children) { + hpdev = container_of(iter, struct hv_pci_dev, + list_entry); + hpdev->reported_missing = true; + } + spin_unlock_irqrestore(&hbus->device_list_lock, flags); + + /* Next, add back any reported devices. */ + for (child_no = 0; child_no < dr->device_count; child_no++) { + found = false; + new_desc = &dr->func[child_no]; + + spin_lock_irqsave(&hbus->device_list_lock, flags); + list_for_each(iter, &hbus->children) { + hpdev = container_of(iter, struct hv_pci_dev, + list_entry); + if ((hpdev->desc.win_slot.slot == + new_desc->win_slot.slot) && + (hpdev->desc.v_id == new_desc->v_id) && + (hpdev->desc.d_id == new_desc->d_id) && + (hpdev->desc.ser == new_desc->ser)) { + hpdev->reported_missing = false; + found = true; + } + } + spin_unlock_irqrestore(&hbus->device_list_lock, flags); + + if (!found) { + hpdev = new_pcichild_device(hbus, new_desc); + if (!hpdev) + pr_err("couldn't record a child device.\n"); + } + } + + /* Move missing children to a list on the stack. */ + spin_lock_irqsave(&hbus->device_list_lock, flags); + do { + found = false; + list_for_each(iter, &hbus->children) { + hpdev = container_of(iter, struct hv_pci_dev, + list_entry); + if (hpdev->reported_missing) { + found = true; + hv_pcichild_dec(hpdev, hv_pcidev_ref_childlist); + list_del(&hpdev->list_entry); + list_add_tail(&hpdev->list_entry, &removed); + break; + } + } + } while (found); + spin_unlock_irqrestore(&hbus->device_list_lock, flags); + + /* Delete everything that should no longer exist. */ + while (!list_empty(&removed)) { + hpdev = list_first_entry(&removed, struct hv_pci_dev, + list_entry); + list_del(&hpdev->list_entry); + hv_pcichild_dec(hpdev, hv_pcidev_ref_initial); + } + + /* Tell the core to rescan bus because there may have been changes. */ + if (hbus->state == hv_pcibus_installed) { + pci_lock_rescan_remove(); + pci_scan_child_bus(hbus->pci_bus); + pci_unlock_rescan_remove(); + } else { + survey_child_resources(hbus); + } + + up(&hbus->enum_sem); + hv_pcibus_dec(hbus); + kfree(dr); +} + +/** + * hv_pci_devices_present() - Handles list of new children + * @hbus: Root PCI bus, as understood by this driver + * @relations: Packet from host listing children + * + * This function is invoked whenever a new list of devices for + * this bus appears. + */ +static void hv_pci_devices_present(struct hv_pcibus_device *hbus, + struct pci_bus_relations *relations) +{ + struct hv_dr_state *dr; + struct hv_dr_work *dr_wrk; + unsigned long flags; + + dr_wrk = kzalloc(sizeof(*dr_wrk), GFP_NOWAIT); + + if (!dr_wrk) + return; + + dr = kzalloc(offsetof(struct hv_dr_state, func) + + (sizeof(struct pci_function_description) * + (relations->device_count)), GFP_NOWAIT); + + if (!dr) { + kfree(dr_wrk); + return; + } + + INIT_WORK(&dr_wrk->wrk, pci_devices_present_work); + dr_wrk->bus = hbus; + dr->device_count = relations->device_count; + if (dr->device_count != 0) { + memcpy(dr->func, relations->func, + sizeof(struct pci_function_description) * + dr->device_count); + } + + spin_lock_irqsave(&hbus->device_list_lock, flags); + list_add_tail(&dr->list_entry, &hbus->dr_list); + spin_unlock_irqrestore(&hbus->device_list_lock, flags); + + hv_pcibus_inc(hbus); + schedule_work(&dr_wrk->wrk); +} + +/** + * hv_eject_device_work() - Asynchronously handles ejection + * @work: Work struct embedded in internal device struct + * + * This function handles ejecting a device. Windows will + * attempt to gracefully eject a device, waiting 60 seconds to + * hear back from the guest OS that this completed successfully. + * If this timer expires, the device will be forcibly removed. + */ +static void hv_eject_device_work(struct work_struct *work) +{ + struct pci_eject_response *ejct_pkt; + struct hv_pci_dev *hpdev; + struct pci_dev *pdev; + unsigned long flags; + int wslot; + struct { + struct pci_packet pkt; + u8 buffer[sizeof(struct pci_eject_response) - + sizeof(struct pci_message)]; + } ctxt; + + hpdev = container_of(work, struct hv_pci_dev, wrk); + + if (hpdev->state != hv_pcichild_ejecting) { + hv_pcichild_dec(hpdev, hv_pcidev_ref_pnp); + return; + } + + wslot = wslot_to_devfn(hpdev->desc.win_slot.slot); + pdev = pci_get_domain_bus_and_slot(hpdev->hbus->sysdata.domain, 0, + wslot); + if (pdev) { + pci_dev_get(pdev); + pci_stop_and_remove_bus_device(pdev); + pci_dev_put(pdev); + } + + memset(&ctxt, 0, sizeof(ctxt)); + ejct_pkt = (struct pci_eject_response *)&ctxt.pkt.message; + ejct_pkt->message_type = PCI_EJECTION_COMPLETE; + ejct_pkt->wslot.slot = hpdev->desc.win_slot.slot; + vmbus_sendpacket(hpdev->hbus->hdev->channel, ejct_pkt, + sizeof(*ejct_pkt), (unsigned long)&ctxt.pkt, + VM_PKT_DATA_INBAND, 0); + + spin_lock_irqsave(&hpdev->hbus->device_list_lock, flags); + list_del(&hpdev->list_entry); + spin_unlock_irqrestore(&hpdev->hbus->device_list_lock, flags); + + hv_pcichild_dec(hpdev, hv_pcidev_ref_childlist); + hv_pcichild_dec(hpdev, hv_pcidev_ref_pnp); + hv_pcibus_dec(hpdev->hbus); +} + +/** + * hv_pci_eject_device() - Handles device ejection + * @hpdev: Internal device tracking struct + * + * This function is invoked when an ejection packet arrives. It + * just schedules work so that we don't re-enter the packet + * delivery code handling the ejection. + */ +static void hv_pci_eject_device(struct hv_pci_dev *hpdev) +{ + hpdev->state = hv_pcichild_ejecting; + hv_pcichild_inc(hpdev, hv_pcidev_ref_pnp); + INIT_WORK(&hpdev->wrk, hv_eject_device_work); + hv_pcibus_inc(hpdev->hbus); + schedule_work(&hpdev->wrk); +} + +/** + * hv_pci_onchannelcallback() - Handles incoming packets + * @context: Internal bus tracking struct + * + * This function is invoked whenever the host sends a packet to + * this channel (which is private to this root PCI bus). + */ +static void hv_pci_onchannelcallback(void *context) +{ + const int packet_size = 0x100; + int ret; + struct hv_pcibus_device *hbus = context; + u32 bytes_recvd; + u64 req_id; + struct vmpacket_descriptor *desc; + unsigned char *buffer; + int bufferlen = packet_size; + struct pci_packet *comp_packet; + struct pci_response *response; + struct pci_incoming_message *new_message; + struct pci_bus_relations *bus_rel; + struct pci_dev_incoming *dev_message; + struct hv_pci_dev *hpdev; + + buffer = kmalloc(bufferlen, GFP_ATOMIC); + if (!buffer) + return; + + while (1) { + ret = vmbus_recvpacket_raw(hbus->hdev->channel, buffer, bufferlen, + &bytes_recvd, &req_id); + + if (ret == -ENOBUFS) { + kfree(buffer); + /* Handle large packet */ + bufferlen = bytes_recvd; + buffer = kmalloc(bytes_recvd, GFP_ATOMIC); + if (!buffer) + return; + continue; + } + + /* + * All incoming packets must be at least as large as a + * response. + */ + if (bytes_recvd <= sizeof(struct pci_response)) { + kfree(buffer); + return; + } + desc = (struct vmpacket_descriptor *)buffer; + + switch (desc->type) { + case VM_PKT_COMP: + + /* + * The host is trusted, and thus its safe to interpret + * this transaction ID as a pointer. + */ + comp_packet = (struct pci_packet *)req_id; + response = (struct pci_response *)buffer; + comp_packet->completion_func(comp_packet->compl_ctxt, + response, + bytes_recvd); + kfree(buffer); + return; + + case VM_PKT_DATA_INBAND: + + new_message = (struct pci_incoming_message *)buffer; + switch (new_message->message_type.message_type) { + case PCI_BUS_RELATIONS: + + bus_rel = (struct pci_bus_relations *)buffer; + if (bytes_recvd < + offsetof(struct pci_bus_relations, func) + + (sizeof(struct pci_function_description) * + (bus_rel->device_count))) { + pr_err("bus relations too small\n"); + break; + } + + hv_pci_devices_present(hbus, bus_rel); + break; + + case PCI_EJECT: + + dev_message = (struct pci_dev_incoming *)buffer; + hpdev = lookup_hv_dev(hbus, + dev_message->wslot.slot); + if (hpdev) { + hv_pci_eject_device(hpdev); + hv_pcichild_dec(hpdev, + hv_pcidev_ref_by_slot); + } + break; + + default: + pr_warn("Unimplemented protocol message %x\n", + new_message->message_type.message_type); + break; + } + break; + + default: + pr_err("unhandled packet type %d, tid %llx len %d\n", + desc->type, req_id, bytes_recvd); + break; + } + break; + } +} + +/** + * hv_pci_protocol_negotiation() - Set up protocol + * @hdev: Vmbus's tracking struct for this root PCI bus + * + * This driver is intended to support running on Windows 10 + * (server) and later versions. It will not run on earlier + * versions, as they assume that many of the operations which + * Linux needs accomplished with a spinlock held were done via + * asynchronous messaging via VMBus. Windows 10 increases the + * surface area of PCI emulation so that these actions can take + * place by suspending a virtual processor for their duration. + * + * This function negotiates the channel protocol version, + * failing if the host doesn't support the necessary protocol + * level. + */ +static int hv_pci_protocol_negotiation(struct hv_device *hdev) +{ + struct pci_version_request *version_req; + struct hv_pci_compl comp_pkt; + struct pci_packet *pkt; + int ret; + + /* + * Initiate the hand shake with the host and negotiate + * a version that the host can support. We start with the + * highest version number and go down if the host cannot + * support it. + */ + + pkt = kzalloc(sizeof(*pkt) + sizeof(*version_req), GFP_KERNEL); + if (!pkt) + return -ENOMEM; + + init_completion(&comp_pkt.host_event); + pkt->completion_func = hv_pci_generic_compl; + pkt->compl_ctxt = &comp_pkt; + version_req = (struct pci_version_request *)&pkt->message; + version_req->message_type.message_type = PCI_QUERY_PROTOCOL_VERSION; + version_req->protocol_version = PCI_PROTOCOL_VERSION_CURRENT; + + ret = vmbus_sendpacket(hdev->channel, version_req, + sizeof(struct pci_version_request), + (unsigned long)pkt, VM_PKT_DATA_INBAND, + VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED); + if (ret) + goto exit; + + wait_for_completion(&comp_pkt.host_event); + + if (comp_pkt.completion_status < 0) { + pr_err("PCI Pass-through VSP failed version request %x\n", + comp_pkt.completion_status); + ret = -EPROTO; + goto exit; + } + + ret = 0; + +exit: + + kfree(pkt); + return ret; +} + +/** + * hv_pci_free_bridge_windows() - Release memory regions for the + * bus + * @hbus: Root PCI bus, as understood by this driver + */ +static void hv_pci_free_bridge_windows(struct hv_pcibus_device *hbus) +{ + if (hbus->low_mmio_space && hbus->low_mmio_res) { + hbus->low_mmio_res->flags |= IORESOURCE_BUSY; + release_mem_region(hbus->low_mmio_res->start, + resource_size(hbus->low_mmio_res)); + } + + if (hbus->high_mmio_space && hbus->high_mmio_res) { + hbus->high_mmio_res->flags |= IORESOURCE_BUSY; + release_mem_region(hbus->high_mmio_res->start, + resource_size(hbus->high_mmio_res)); + } +} + +/** + * hv_pci_allocate_bridge_windows() - Allocate memory regions + * for the bus + * @hbus: Root PCI bus, as understood by this driver + * + * Return: 0 on success, -errno on failure + */ +static int hv_pci_allocate_bridge_windows(struct hv_pcibus_device *hbus) +{ + resource_size_t align; + int ret; + + if (hbus->low_mmio_space) { + align = 1 << (63 - __builtin_clzll(hbus->low_mmio_space)); + ret = vmbus_allocate_mmio(&hbus->low_mmio_res, hbus->hdev, 0, + (u64)(u32)0xffffffff, + hbus->low_mmio_space, + align, false); + if (ret) + return ret; + + hbus->low_mmio_res->flags |= IORESOURCE_WINDOW; + hbus->low_mmio_res->flags &= ~IORESOURCE_BUSY; + pci_add_resource(&hbus->resources_for_children, + hbus->low_mmio_res); + } + + if (hbus->high_mmio_space) { + align = 1 << (63 - __builtin_clzll(hbus->high_mmio_space)); + ret = vmbus_allocate_mmio(&hbus->high_mmio_res, hbus->hdev, + 0x100000000, -1, + hbus->high_mmio_space, align, + false); + if (ret) + goto release_low_mmio; + + hbus->high_mmio_res->flags |= IORESOURCE_WINDOW; + hbus->high_mmio_res->flags &= ~IORESOURCE_BUSY; + pci_add_resource(&hbus->resources_for_children, + hbus->high_mmio_res); + } + + return 0; + +release_low_mmio: + + if (hbus->low_mmio_res) { + release_mem_region(hbus->low_mmio_res->start, + resource_size(hbus->low_mmio_res)); + } + + return ret; +} + +/** + * hv_pci_enter_d0() - Bring the "bus" into the D0 power state + * @hdev: Vmbus's tracking struct for this root PCI bus + * + * Return: 0 on success, -errno on failure + */ +static int hv_pci_enter_d0(struct hv_device *hdev) +{ + struct hv_pcibus_device *hbus = hv_get_drvdata(hdev); + struct pci_bus_d0_entry *d0_entry; + struct hv_pci_compl comp_pkt; + struct pci_packet *pkt; + int ret; + + /* + * Tell the host that the bus is ready to use, and moved into the + * powered-on state. This includes telling the host which region + * of memory-mapped I/O space has been chosen for configuration space + * access. + */ + + pkt = kzalloc(sizeof(*pkt) + sizeof(*d0_entry), GFP_KERNEL); + if (!pkt) + return -ENOMEM; + + init_completion(&comp_pkt.host_event); + pkt->completion_func = hv_pci_generic_compl; + pkt->compl_ctxt = &comp_pkt; + d0_entry = (struct pci_bus_d0_entry *)&pkt->message; + d0_entry->message_type.message_type = PCI_BUS_D0ENTRY; + d0_entry->mmio_base = hbus->mem_config->start; + + ret = vmbus_sendpacket(hdev->channel, d0_entry, sizeof(*d0_entry), + (unsigned long)pkt, VM_PKT_DATA_INBAND, + VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED); + if (ret) + goto exit; + wait_for_completion(&comp_pkt.host_event); + + if (comp_pkt.completion_status < 0) { + pr_err("PCI Pass-through VSP failed D0 Entry with status %x\n", + comp_pkt.completion_status); + ret = -EPROTO; + goto exit; + } + + ret = 0; + +exit: + + kfree(pkt); + return ret; +} + +/** + * hv_pci_query_relations() - Ask host to send list of child + * devices + * @hdev: Vmbus's tracking struct for this root PCI bus + * + * Return: 0 on success, -errno on failure + */ +static int hv_pci_query_relations(struct hv_device *hdev) +{ + struct hv_pcibus_device *hbus = hv_get_drvdata(hdev); + struct pci_message message; + struct completion comp; + int ret; + + /* + * Ask the host to send along the list of child devices. + */ + + init_completion(&comp); + if (cmpxchg(&hbus->survey_event, NULL, &comp)) + return -ENOTEMPTY; + + memset(&message, 0, sizeof(message)); + message.message_type = PCI_QUERY_BUS_RELATIONS; + + ret = vmbus_sendpacket(hdev->channel, &message, sizeof(message), + 0, VM_PKT_DATA_INBAND, 0); + if (ret) + return ret; + + wait_for_completion(&comp); + return 0; +} + +/** + * hv_send_resources_allocated() - Report local resource choices + * @hdev: Vmbus's tracking struct for this root PCI bus + * + * The host OS is expecting to be sent a request as a message + * which contains all the resources that the device will use. + * The response contains those same resources, "translated" + * which is to say, the values which should be used by the + * hardware, when it delivers an interrupt. (MMIO resources are + * used in local terms.) This is nice for Windows, and lines up + * with the FDO/PDO split, which doesn't exist in Linux. Linux + * is deeply expecting to scan an emulated PCI configuration + * space. So this message is sent here only to drive the state + * machine on the host forward. + * + * Return: 0 on success, -errno on failure + */ +static int hv_send_resources_allocated(struct hv_device *hdev) +{ + struct hv_pcibus_device *hbus = hv_get_drvdata(hdev); + struct pci_resources_assigned *res_assigned; + struct hv_pci_compl comp_pkt; + struct hv_pci_dev *hpdev; + struct pci_packet *pkt; + u32 wslot; + int ret; + + pkt = kmalloc(sizeof(*pkt) + sizeof(*res_assigned), GFP_KERNEL); + if (!pkt) + return -ENOMEM; + + ret = 0; + + for (wslot = 0; wslot < 256; wslot++) { + hpdev = lookup_hv_dev(hbus, wslot); + if (!hpdev) + continue; + + memset(pkt, 0, sizeof(*pkt) + sizeof(*res_assigned)); + init_completion(&comp_pkt.host_event); + pkt->completion_func = hv_pci_generic_compl; + pkt->compl_ctxt = &comp_pkt; + pkt->message.message_type = PCI_RESOURCES_ASSIGNED; + res_assigned = (struct pci_resources_assigned *)&pkt->message; + res_assigned->wslot.slot = hpdev->desc.win_slot.slot; + + hv_pcichild_dec(hpdev, hv_pcidev_ref_by_slot); + + ret = vmbus_sendpacket( + hdev->channel, &pkt->message, + sizeof(*res_assigned), + (unsigned long)pkt, + VM_PKT_DATA_INBAND, + VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED); + if (ret) + break; + + wait_for_completion(&comp_pkt.host_event); + + if (comp_pkt.completion_status < 0) { + ret = -EPROTO; + pr_err("resource allocated returned 0x%x", + comp_pkt.completion_status); + break; + } + } + + kfree(pkt); + return ret; +} + +/** + * hv_send_resources_released() - Report local resources + * released + * @hdev: Vmbus's tracking struct for this root PCI bus + * + * Return: 0 on success, -errno on failure + */ +static int hv_send_resources_released(struct hv_device *hdev) +{ + struct hv_pcibus_device *hbus = hv_get_drvdata(hdev); + struct pci_child_message pkt; + struct hv_pci_dev *hpdev; + u32 wslot; + int ret; + + for (wslot = 0; wslot < 256; wslot++) { + hpdev = lookup_hv_dev(hbus, wslot); + if (!hpdev) + continue; + + memset(&pkt, 0, sizeof(pkt)); + pkt.message_type = PCI_RESOURCES_RELEASED; + pkt.wslot.slot = hpdev->desc.win_slot.slot; + + hv_pcichild_dec(hpdev, hv_pcidev_ref_by_slot); + + ret = vmbus_sendpacket(hdev->channel, &pkt, sizeof(pkt), 0, + VM_PKT_DATA_INBAND, 0); + if (ret) + return ret; + } + + return 0; +} + +static void hv_pcibus_inc(struct hv_pcibus_device *hbus) +{ + pr_devel("+> %d %p\n", atomic_read(&hbus->remove_lock) + 1, hbus); + atomic_inc(&hbus->remove_lock); +} + +static void hv_pcibus_dec(struct hv_pcibus_device *hbus) +{ + pr_devel("-> %d %p\n", atomic_read(&hbus->remove_lock) - 1, hbus); + if (atomic_dec_and_test(&hbus->remove_lock)) + complete(&hbus->remove_event); +} + +/** + * hv_pci_probe() - New VMBus channel probe, for a root PCI bus + * @hdev: Vmbus's tracking struct for this root PCI bus + * @dev_id: Indentifies the device itself + * + * Return: 0 on success, -errno on failure + */ +static int hv_pci_probe(struct hv_device *hdev, + const struct hv_vmbus_device_id *dev_id) +{ + struct hv_pcibus_device *hbus; + int ret; + + hbus = kzalloc(sizeof(*hbus), GFP_KERNEL); + if (!hbus) + return -ENOMEM; + + pr_devel("New virtual PCIe bus: %p\n", hbus); + + hbus->hdev = hdev; + atomic_inc(&hbus->remove_lock); + INIT_LIST_HEAD(&hbus->children); + INIT_LIST_HEAD(&hbus->dr_list); + INIT_LIST_HEAD(&hbus->resources_for_children); + spin_lock_init(&hbus->config_lock); + spin_lock_init(&hbus->device_list_lock); + sema_init(&hbus->enum_sem, 1); + init_completion(&hbus->remove_event); + + /* + * The PCI bus "domain" is what is called "segment" in the + * ACPI and other specs. Pull it from the instance ID, + * to get something unique. Bytes 8 and 9 are what is used + * in Windows guests, so do the same thing for consistency. + */ + + hbus->sysdata.domain = hdev->dev_instance.b[9] | + hdev->dev_instance.b[8] << 8; + + ret = vmbus_open(hdev->channel, pci_ring_size, pci_ring_size, NULL, 0, + hv_pci_onchannelcallback, hbus); + if (ret) + goto free_bus; + + hv_set_drvdata(hdev, hbus); + + ret = hv_pci_protocol_negotiation(hdev); + if (ret) + goto close; + + /* + * Set up a region of MMIO space to use for accessing configuration + * space. + */ + ret = vmbus_allocate_mmio(&hbus->mem_config, hdev, 0, -1, + PCI_CONFIG_MMIO_LENGTH, 0x1000, false); + if (ret) + goto close; + + hbus->mem_config->flags |= IORESOURCE_BUSY; + hbus->cfg_addr = ioremap(hbus->mem_config->start, + PCI_CONFIG_MMIO_LENGTH); + if (!hbus->cfg_addr) { + pr_err("Unable to map a virtual address for config space\n"); + ret = -ENOMEM; + goto release; + } + + hbus->sysdata.fwnode = irq_domain_alloc_fwnode(hbus); + if (!hbus->sysdata.fwnode) { + ret = -ENOMEM; + goto unmap; + } + + ret = hv_pcie_init_irq_domain(hbus); + if (ret) + goto free_fwnode; + + ret = hv_pci_query_relations(hdev); + if (ret) + goto free_irq_domain; + + ret = hv_pci_enter_d0(hdev); + if (ret) + goto free_irq_domain; + + ret = hv_pci_allocate_bridge_windows(hbus); + if (ret) + goto free_irq_domain; + + ret = hv_send_resources_allocated(hdev); + if (ret) + goto free_windows; + + prepopulate_bars(hbus); + + hbus->state = hv_pcibus_probed; + + ret = create_root_hv_pci_bus(hbus); + if (ret) + goto free_windows; + + return 0; + +free_windows: + hv_pci_free_bridge_windows(hbus); +free_irq_domain: + hv_pcie_free_irq_domain(hbus); +free_fwnode: + irq_domain_free_fwnode(hbus->sysdata.fwnode); +unmap: + iounmap(hbus->cfg_addr); +release: + release_mem_region(hbus->mem_config->start, PCI_CONFIG_MMIO_LENGTH); +close: + vmbus_close(hdev->channel); +free_bus: + kfree(hbus); + return ret; +} + +/** + * hv_pci_remove() - Remove routine for this VMBus channel + * @hdev: Vmbus's tracking struct for this root PCI bus + * + * Return: 0 on success, -errno on failure + */ +static int hv_pci_remove(struct hv_device *hdev) +{ + int ret; + struct hv_pcibus_device *hbus; + union { + struct pci_packet teardown_packet; + __u8 buffer[0x100]; + } pkt; + struct pci_bus_relations relations; + struct hv_pci_compl comp_pkt; + + hbus = hv_get_drvdata(hdev); + + ret = hv_send_resources_released(hdev); + if (ret) + pr_err("Couldn't send resources released packet(s)\n"); + + memset(&pkt.teardown_packet, 0, sizeof(pkt.teardown_packet)); + init_completion(&comp_pkt.host_event); + pkt.teardown_packet.completion_func = hv_pci_generic_compl; + pkt.teardown_packet.compl_ctxt = &comp_pkt; + pkt.teardown_packet.message.message_type = PCI_BUS_D0EXIT; + + ret = vmbus_sendpacket(hdev->channel, &pkt.teardown_packet.message, + sizeof(struct pci_message), + (unsigned long)&pkt.teardown_packet, + VM_PKT_DATA_INBAND, + VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED); + if (!ret) + wait_for_completion_timeout(&comp_pkt.host_event, 10 * HZ); + + if (hbus->state == hv_pcibus_installed) { + /* Remove the bus from PCI's point of view. */ + pci_lock_rescan_remove(); + pci_stop_root_bus(hbus->pci_bus); + pci_remove_root_bus(hbus->pci_bus); + pci_unlock_rescan_remove(); + } + + vmbus_close(hdev->channel); + + /* Delete any children which might still exist. */ + memset(&relations, 0, sizeof(relations)); + hv_pci_devices_present(hbus, &relations); + + iounmap(hbus->cfg_addr); + release_mem_region(hbus->mem_config->start, PCI_CONFIG_MMIO_LENGTH); + pci_free_resource_list(&hbus->resources_for_children); + hv_pci_free_bridge_windows(hbus); + hv_pcie_free_irq_domain(hbus); + irq_domain_free_fwnode(hbus->sysdata.fwnode); + hv_pcibus_dec(hbus); + wait_for_completion(&hbus->remove_event); + kfree(hbus); + return 0; +} + +static const struct hv_vmbus_device_id hv_pci_id_table[] = { + /* PCI Pass-through Class ID */ + /* 44C4F61D-4444-4400-9D52-802E27EDE19F */ + { HV_PCIE_GUID, }, + { }, +}; + +MODULE_DEVICE_TABLE(vmbus, hv_pci_id_table); + +static struct hv_driver hv_pci_drv = { + .name = "hv_pci", + .id_table = hv_pci_id_table, + .probe = hv_pci_probe, + .remove = hv_pci_remove, +}; + +static void __exit exit_hv_pci_drv(void) +{ + vmbus_driver_unregister(&hv_pci_drv); +} + +static int __init init_hv_pci_drv(void) +{ + return vmbus_driver_register(&hv_pci_drv); +} + +module_init(init_hv_pci_drv); +module_exit(exit_hv_pci_drv); + +MODULE_DESCRIPTION("Hyper-V PCI"); +MODULE_LICENSE("GPL v2"); -- 1.9.1