[PATCH 6/6] drivers:pci:hv: New paravirtual PCI front-end for Hyper-V VMs

From: jakeo
Date: Thu Jun 11 2015 - 12:30:20 EST

From: Jake Oshins <jakeo@xxxxxxxxxxxxx>

drivers:pci:hv: Update MAINTAINERS

drivers:pci:hv: New paravirtual PCI front-end for Hyper-V VMs
Signed-off-by: Jake Oshins <jakeo@xxxxxxxxxxxxx>
---
MAINTAINERS | 1 +
drivers/pci/Kconfig | 9 +
drivers/pci/host/Makefile | 1 +
drivers/pci/host/hv_pcifront.c | 2177 ++++++++++++++++++++++++++++++++++++++++
include/linux/hyperv.h | 18 +
5 files changed, 2206 insertions(+)
create mode 100644 drivers/pci/host/hv_pcifront.c

diff --git a/MAINTAINERS b/MAINTAINERS
index d8afd29..ed8d991 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4759,6 +4759,7 @@ 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 7a8f1c5..e008f68 100644
--- a/drivers/pci/Kconfig
+++ b/drivers/pci/Kconfig
@@ -114,4 +114,13 @@ config PCI_LABEL
def_bool y if (DMI || ACPI)
select NLS

+config HYPERV_VPCI
+ tristate "Hyper-V PCI Frontend"
+ depends on PCI && X86 && HYPERV
+ select PCI_HV
+ default y
+ 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 f733b4e..7bf8442 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..1bdfdd5
--- /dev/null
+++ b/drivers/pci/host/hv_pcifront.c
@@ -0,0 +1,2177 @@
+/*
+ * Copyright (c) Microsoft Corporation.
+ *
+ * Author:
+ * Jake Oshins <jakeo@xxxxxxxxxxxxx>
+ *
+ * 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 <linux/kernel.h>
+#include <linux/jiffies.h>
+#include <linux/mman.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/kthread.h>
+#include <linux/completion.h>
+#include <linux/notifier.h>
+#include <linux/of_pci.h>
+#include <linux/of_platform.h>
+#include <linux/pci.h>
+#include <linux/semaphore.h>
+
+#include <linux/hyperv.h>
+#include <asm/mshyperv.h>
+
+/*
+ * We begin with definitions supporting the Virtual PCI Express protocol
+ * with the host.
+ *
+ * Begin protocol definitions.
+ */
+
+
+/*
+ * Protocol versions. The low word is the minor version, the high word the major
+ * version.
+ */
+
+#define PCI_MAKE_VERSION(Major, Minor) ((__u32)(((Major) << 16) | (Minor)))
+#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
+
+/*
+ * 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.
+ */
+union pci_slot_number {
+ 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 pci_slot_number s_no;
+ __u32 ser; /* serial number */
+} __packed;
+
+/*
+ * 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.
+*/
+struct hv_msi_desc {
+ __u8 vector;
+ __u8 delivery_mode;
+ __u16 vector_count;
+ __u32 reserved;
+ __u64 proc_mask;
+} __packed;
+
+/*
+ * vector_count - same as in 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 pci_slot_number slot;
+} __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 pci_slot_number slot;
+ __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 pci_slot_number slot;
+ __u32 resultant_state; /* In Windows terms */
+ __u32 reserved;
+} __packed;
+
+struct pci_resources_assigned {
+ struct pci_message message_type;
+ union pci_slot_number slot;
+ 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 pci_slot_number slot;
+ 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 pci_slot_number slot;
+ struct tran_int_desc int_desc;
+} __packed;
+
+struct pci_read_block {
+ struct pci_message message_type;
+ int block_id;
+ union pci_slot_number slot;
+ int bytes_requested;
+} __packed;
+
+struct pci_write_block {
+ struct pci_message message_type;
+ int block_id;
+ union pci_slot_number slot;
+ int byte_count;
+ unsigned char bytes[CONFIG_BLOCK_SIZE_MAX];
+} __packed;
+
+struct pci_dev_inval_block {
+ struct pci_incoming_message incoming;
+ union pci_slot_number slot;
+ u64 block_mask;
+} __packed;
+
+struct pci_dev_incoming {
+ struct pci_incoming_message incoming;
+ union pci_slot_number slot;
+} __packed;
+
+struct pci_eject_response {
+ u32 message_type;
+ union pci_slot_number slot;
+ u32 status;
+} __packed;
+
+static int pci_ring_size = (4 * PAGE_SIZE);
+
+/*
+ * 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;
+ spinlock_t device_list_lock;
+ void __iomem *cfg_addr;
+
+ struct semaphore enum_sem;
+ struct list_head resources_for_children;
+
+ /* Lists protected by device_list_lock */
+ struct list_head children;
+ struct list_head dr_list;
+ struct work_struct wrk;
+};
+
+/* 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_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"
+};
+
+struct hv_pci_dev {
+ /* List protected by pci_rescan_remove_lock */
+ struct list_head list_entry;
+ atomic_t refs;
+ enum hv_pcichild_state state;
+ /* 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 pci_function_description desc;
+ bool reported_missing;
+ struct hv_pcibus_device *hbus;
+ struct work_struct wrk;
+ void (*block_invalidate)(void *context, u64 block_mask);
+ void *invalidate_context;
+};
+
+struct hv_pci_compl {
+ struct completion host_event;
+ __s32 completion_status;
+};
+
+struct x86_msi_ops hv_msi;
+
+/**
+ * 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.
+ *
+ * @param context - Set up by the sender of the packet.
+ * @param resp - The response packet
+ * @param resp_packet_size - Size in bytes of the packet
+ */
+static
+void
+hv_pci_generic_compl(void *context, struct pci_response *resp,
+ int resp_packet_size)
+{
+ struct hv_pci_compl *comp_pkt = (struct hv_pci_compl *)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_pcidev(struct hv_pcibus_device *hbus,
+ u32 slot);
+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);
+
+/**
+ * Windows uses a slightly different representation of PCI slot.
+ * These helper functions convert between what's sent in the
+ * protocol messages and what's used in Linux.
+ *
+ * @param devfn - The Linux representation of PCI slot
+ *
+ * @return u32 - The Windows representation
+ */
+static u32 devfn_to_slot(int devfn)
+{
+ union pci_slot_number slot;
+
+ slot.slot = 0;
+ slot.bits.func = PCI_SLOT(devfn) | (PCI_FUNC(devfn) << 5);
+
+ return slot.slot;
+}
+
+static int slot_to_devfn(u32 slot)
+{
+ union pci_slot_number slot_no;
+
+ slot_no.slot = slot;
+ return PCI_DEVFN(0, slot_no.bits.func);
+}
+
+/**
+ * These internal functions read and write config space for a
+ * PCI device.
+ *
+ * @param hpdev - The PCI driver's representation of the device
+ * @param where - Offset within config space
+ * @param size - Size of the transfer
+ * @param val - The data being transferred
+ */
+static void _hv_pcifront_read_config(struct hv_pci_dev *hpdev, int where,
+ int size, u32 *val)
+{
+ unsigned long flags;
+ void __iomem *addr = ((u8 *)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.s_no.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);
+ }
+
+}
+
+static void _hv_pcifront_write_config(struct hv_pci_dev *hpdev, int where,
+ int size, u32 val)
+{
+ unsigned long flags;
+ void __iomem *addr = ((__u8 *)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.s_no.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 = NULL;
+
+ hpdev = lookup_hv_pcidev(hbus, devfn_to_slot(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 = NULL;
+
+ hpdev = lookup_hv_pcidev(hbus, devfn_to_slot(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,
+};
+
+/*
+ * Paravirtual backchannel
+ *
+ * Windows SR-IOV provides a backchannel mechanism in software for communication
+ * between a VF driver and a PF driver. These "configuration blocks" are
+ * similar in concept to PCI configuration space, but instead of doing reads and
+ * writes in 32-bit chunks through a very slow path, packets of up to 128 bytes
+ * can be sent or received asynchronously.
+ *
+ * Nearly every SR-IOV device contains just such a communications channel in
+ * hardware, so using this one in software is usually optional. Using the
+ * software channel, however, allows driver implementers to leverage software
+ * tools that fuzz the communications channel looking for vulnerabilities.
+ *
+ * The usage model for these packets puts the responsibility for reading or
+ * writing on the VF driver. The VF driver sends a read or a write packet,
+ * indicating which "block" is being referred to by number.
+ *
+ * If the PF driver wishes to initiate communication, it can "invalidate" one or
+ * more of the first 64 blocks. This invalidation is delivered via a callback
+ * supplied by the VF driver by this driver.
+ *
+ * No protocol is implied, except that supplied by the PF and VF drivers.
+ */
+
+struct hv_read_config_compl {
+ struct hv_pci_compl gen_compl;
+ void *buf;
+ int len;
+ int bytes_returned;
+};
+
+static
+void
+hv_pci_read_config_compl(void *context, struct pci_response *resp,
+ int resp_packet_size)
+{
+ struct hv_read_config_compl *comp_pkt =
+ (struct hv_read_config_compl *)context;
+ int data_len;
+ void *data;
+
+ data_len = resp_packet_size - offsetof(struct pci_response, status);
+
+ if (data_len > 0) {
+ data = ((char *)resp) + offsetof(struct pci_response, status);
+ memcpy(comp_pkt->buf, data, max(comp_pkt->len, data_len));
+ }
+ comp_pkt->bytes_returned = data_len;
+ complete(&comp_pkt->gen_compl.host_event);
+}
+
+int hv_read_config_block(struct pci_dev *pdev, void *buf, int buf_len,
+ int block_id, int *bytes_returned)
+{
+ struct hv_pcibus_device *hbus =
+ container_of(pdev->bus->sysdata, struct hv_pcibus_device,
+ sysdata);
+ struct {
+ struct pci_packet pkt;
+ char buf[sizeof(struct pci_read_block) -
+ offsetof(struct pci_packet, message)];
+ } pkt;
+ struct hv_read_config_compl comp_pkt;
+ struct pci_read_block *read_blk;
+ int ret;
+
+ if (buf_len > CONFIG_BLOCK_SIZE_MAX)
+ return -ENOSPC;
+
+ memset(&pkt, 0, sizeof(pkt));
+ init_completion(&comp_pkt.gen_compl.host_event);
+ pkt.pkt.completion_func = hv_pci_read_config_compl;
+ pkt.pkt.compl_ctxt = &comp_pkt;
+ read_blk = (struct pci_read_block *)&pkt.pkt.message;
+ read_blk->message_type.message_type = PCI_READ_BLOCK;
+ read_blk->slot.slot = devfn_to_slot(pdev->devfn);
+ read_blk->bytes_requested = buf_len;
+
+ ret = vmbus_sendpacket(hbus->hdev->channel, &pkt, sizeof(pkt),
+ (unsigned long)&comp_pkt, VM_PKT_DATA_INBAND,
+ VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
+ if (!ret) {
+ wait_for_completion(&comp_pkt.gen_compl.host_event);
+ *bytes_returned = comp_pkt.bytes_returned;
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL(hv_read_config_block);
+
+int hv_write_config_block(struct pci_dev *pdev, void *buf, int len,
+ int block_id)
+{
+ struct hv_pcibus_device *hbus =
+ container_of(pdev->bus->sysdata, struct hv_pcibus_device,
+ sysdata);
+ struct {
+ struct pci_packet pkt;
+ char buf[sizeof(struct pci_write_block) -
+ offsetof(struct pci_packet, message)];
+ } pkt;
+ struct hv_pci_compl comp_pkt;
+ struct pci_write_block *write_blk;
+ u32 pkt_size;
+ int ret;
+
+ if (len > CONFIG_BLOCK_SIZE_MAX)
+ return -ENOSPC;
+
+ memset(&pkt, 0, sizeof(pkt));
+ init_completion(&comp_pkt.host_event);
+ pkt.pkt.completion_func = hv_pci_generic_compl;
+ pkt.pkt.compl_ctxt = &comp_pkt;
+ write_blk = (struct pci_write_block *)&pkt.pkt.message;
+ write_blk->message_type.message_type = PCI_WRITE_BLOCK;
+ write_blk->slot.slot = devfn_to_slot(pdev->devfn);
+ write_blk->byte_count = len;
+ memcpy(write_blk->bytes, buf, len);
+ pkt_size = offsetof(struct pci_write_block, bytes) + len;
+
+ ret = vmbus_sendpacket(hbus->hdev->channel, &pkt, pkt_size,
+ (unsigned long)&pkt.pkt, VM_PKT_DATA_INBAND,
+ VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
+ if (!ret)
+ wait_for_completion(&comp_pkt.host_event);
+
+ return ret;
+}
+EXPORT_SYMBOL(hv_write_config_block);
+
+int hv_register_block_invalidate(struct pci_dev *pdev, void *context,
+ void (*block_invalidate)(void *context,
+ u64 block_mask))
+{
+ struct hv_pcibus_device *hbus =
+ container_of(pdev->bus->sysdata, struct hv_pcibus_device,
+ sysdata);
+ struct hv_pci_dev *hpdev;
+
+ hpdev = lookup_hv_pcidev(hbus, devfn_to_slot(pdev->devfn));
+ if (!hpdev)
+ return -ENODEV;
+
+ hpdev->block_invalidate = block_invalidate;
+ hpdev->invalidate_context = context;
+
+ hv_pcichild_dec(hpdev, hv_pcidev_ref_by_slot);
+ return 0;
+
+}
+EXPORT_SYMBOL(hv_register_block_invalidate);
+
+/* Interrupt management hooks */
+
+int hv_set_affinity(struct irq_data *data, const struct cpumask *dest,
+ bool force)
+{
+ return 0;
+}
+
+int hv_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type)
+{
+ struct msi_desc *msidesc;
+ struct irq_chip *chip;
+ int ret;
+
+ /*
+ * Call the base function which will do everything related to setting up
+ * the tracking structures.
+ */
+
+ ret = hv_msi.setup_msi_irqs(pdev, nvec, type);
+ if (ret)
+ return ret;
+
+ list_for_each_entry(msidesc, &pdev->msi_list, list) {
+ if (msidesc->irq) {
+ chip = irq_get_chip(msidesc->irq);
+ /*
+ * Replace the affinity callback so that it doesn't
+ * rearrage the message in the hardware.
+ */
+ chip->irq_set_affinity = hv_set_affinity;
+ }
+ }
+
+ return 0;
+}
+
+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 =
+ (struct compose_comp_ctxt *)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);
+}
+
+void hv_compose_msi_msg(struct pci_dev *pdev, unsigned int irq,
+ unsigned int dest, struct msi_msg *msg, u8 hpet_id)
+{
+ struct irq_cfg *cfg = irq_get_chip_data(irq);
+ struct hv_pci_dev *hpdev = NULL;
+ struct pci_create_interrupt *int_pkt;
+ struct compose_comp_ctxt comp;
+ struct {
+ struct pci_packet pkt;
+ u8 buffer[sizeof(struct pci_create_interrupt) -
+ sizeof(struct pci_message)];
+ } ctxt;
+ struct hv_pcibus_device *hbus =
+ container_of(pdev->bus->sysdata, struct hv_pcibus_device,
+ sysdata);
+ int cpu;
+ int ret;
+
+ hpdev = lookup_hv_pcidev(hbus, devfn_to_slot(pdev->devfn));
+ if (!hpdev)
+ return;
+
+ memset(&ctxt, 0, sizeof(ctxt));
+ init_completion(&comp.comp_pkt.host_event);
+ ctxt.pkt.completion_func = hv_pci_compose_compl;
+ ctxt.pkt.compl_ctxt = &comp;
+ int_pkt = (struct pci_create_interrupt *)&ctxt.pkt.message;
+ int_pkt->message_type.message_type = PCI_CREATE_INTERRUPT_MESSAGE;
+ int_pkt->slot.slot = hpdev->desc.s_no.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;
+ for_each_cpu(cpu, cfg->domain)
+ int_pkt->int_desc.proc_mask |=
+ (1 << vmbus_procnum_to_vpnum(cpu));
+
+ ret = vmbus_sendpacket(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);
+ msg->address_hi = 0;
+ msg->address_lo = 0;
+ msg->data = 0;
+ } else {
+ 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);
+}
+
+void hv_teardown_msi_irqs(struct pci_dev *pdev)
+{
+ struct hv_pci_dev *hpdev = NULL;
+ struct pci_delete_interrupt *int_pkt;
+ struct msi_desc *msidesc;
+ struct {
+ struct pci_packet pkt;
+ u8 buffer[sizeof(struct pci_delete_interrupt) -
+ sizeof(struct pci_message)];
+ } ctxt;
+ struct hv_pcibus_device *hbus =
+ container_of(pdev->bus->sysdata, struct hv_pcibus_device,
+ sysdata);
+
+ hpdev = lookup_hv_pcidev(hbus, devfn_to_slot(pdev->devfn));
+
+ list_for_each_entry(msidesc, &pdev->msi_list, list) {
+ 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->slot.slot = hpdev->desc.s_no.slot;
+ int_pkt->int_desc.address = (u64)msidesc->msg.address_hi << 32 |
+ msidesc->msg.address_lo;
+ int_pkt->int_desc.data = msidesc->msg.data;
+ vmbus_sendpacket(hbus->hdev->channel, int_pkt, sizeof(*int_pkt),
+ (unsigned long)&ctxt.pkt, VM_PKT_DATA_INBAND,
+ 0);
+ }
+
+ hv_pcichild_dec(hpdev, hv_pcidev_ref_by_slot);
+ hv_msi.teardown_msi_irqs(pdev);
+}
+
+void hv_restore_msi_irqs(struct pci_dev *pdev)
+{
+ hv_msi.restore_msi_irqs(pdev);
+}
+
+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];
+ pr_devel("bar_val: 0x%llx\n", bar_val);
+ if (bar_val & PCI_BASE_ADDRESS_MEM_TYPE_64)
+ bar_val |=
+ ((u64)hpdev->probed_bar[++i] << 32);
+ else
+ bar_val |= 0xffffffff00000000ULL;
+
+ bar_size = 1 +
+ ~(bar_val & PCI_BASE_ADDRESS_MEM_MASK);
+ pr_devel("bar_size: 0x%llx\n", bar_size);
+
+ 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);
+
+ pr_devel("high_mmio_space: 0x%llx low_mmio_space: 0x%llx\n",
+ hbus->high_mmio_space, hbus->low_mmio_space);
+
+ complete(event);
+}
+
+/**
+ * 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_bar_size = 0;
+ resource_size_t low_bar_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_bar_size = 1<<(63-__builtin_clzll(hbus->low_mmio_space));
+ low_base = hbus->low_mmio_res->start;
+ }
+
+ if (hbus->high_mmio_space) {
+ high_bar_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 = 1ULL +
+ ~(bar_val & PCI_BASE_ADDRESS_MEM_MASK);
+
+ if (high) {
+
+ if (high_bar_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_bar_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_bar_size <= 1) && (low_bar_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_bar_size >>= 1;
+ low_bar_size >>= 1;
+ } while (high_bar_size || low_bar_size);
+
+ spin_unlock_irqrestore(&hbus->device_list_lock, flags);
+}
+
+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;
+
+ 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;
+};
+
+/**
+ * This function is invoked on completion of a Query Resource
+ * Requirements packet.
+ *
+ * @param context - The completion context.
+ * @param resp - The respose that came from the host.
+ * @param resp_packet_size - The size in bytes of resp.
+ */
+static void q_resource_requirements(void *context, struct pci_response *resp,
+ int resp_packet_size)
+{
+ struct q_res_req_compl *completion = (struct q_res_req_compl *)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];
+ pr_devel("BAR[%d]: %08x\n", 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);
+ }
+}
+
+/**
+ * This function creates the tracking structure for a new child
+ * device and kicks off the process of figuring out what it is.
+ *
+ * @param hbus - The internal struct tracking this root PCI bus.
+ * @param desc - The information supplied so far from the host
+ * about the device.
+ *
+ * @return struct hv_pci_dev*
+ */
+static
+struct hv_pci_dev *
+new_pcichild_device(struct hv_pcibus_device *hbus,
+ struct pci_function_description *desc)
+{
+ struct hv_pci_dev *hpdev = NULL;
+ 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(struct hv_pci_dev), 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->s_no.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->slot.slot = desc->s_no.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 new_pcichild_device_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;
+
+new_pcichild_device_error:
+
+ kfree(hpdev);
+ return NULL;
+}
+
+static struct hv_pci_dev *lookup_hv_pcidev(struct hv_pcibus_device *hbus,
+ u32 slot)
+{
+ 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.s_no.slot == slot) {
+ hpdev = iter;
+ hv_pcichild_inc(hpdev, hv_pcidev_ref_by_slot);
+ break;
+ }
+ }
+ spin_unlock_irqrestore(&hbus->device_list_lock, flags);
+
+ return hpdev;
+}
+
+/**
+ * "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 the host sent it. 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;
+
+ INIT_LIST_HEAD(&removed);
+
+ if (down_interruptible(&hbus->enum_sem))
+ 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);
+ }
+
+ if (dr == NULL) {
+ spin_unlock_irqrestore(&hbus->device_list_lock, flags);
+ goto present_exit;
+ }
+
+ /* First, mark all existing children as reported missing. */
+ 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.s_no.slot ==
+ new_desc->s_no.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");
+ goto present_exit;
+ }
+ }
+ }
+
+ /* 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);
+
+present_exit:
+
+ /* 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);
+
+ if (dr)
+ kfree(dr);
+ kfree(dr_wrk);
+}
+
+/**
+ * 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(struct hv_dr_work), GFP_NOWAIT);
+
+ if (!dr_wrk)
+ goto pci_devices_present_error;
+
+ dr = kzalloc(offsetof(struct hv_dr_state, func) +
+ (sizeof(struct pci_function_description) *
+ (relations->device_count)), GFP_NOWAIT);
+
+ if (!dr) {
+ kfree(dr_wrk);
+ goto pci_devices_present_error;
+ }
+
+ 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);
+ return;
+
+pci_devices_present_error:
+ pr_err("Couldn't allocate memory to process new device list\n");
+}
+
+/**
+ * These functions handle 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;
+ 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;
+ }
+
+ pdev = pci_get_domain_bus_and_slot(hpdev->hbus->sysdata.domain, 0,
+ slot_to_devfn(hpdev->desc.s_no.slot));
+ 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->slot.slot = hpdev->desc.s_no.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);
+}
+
+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);
+}
+
+/**
+ * This function is invoked whenever the host sends a packet to
+ * this channel (which is private to this root PCI bus).
+ *
+ * @param context - The bus tracking struct.
+ */
+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_inval_block *inval;
+ struct pci_dev_incoming *dev_message;
+ struct hv_pci_dev *hpdev;
+
+ buffer = kmalloc(bufferlen, GFP_ATOMIC);
+ if (!buffer)
+ return;
+
+ do {
+ ret = vmbus_recvpacket_raw(hbus->hdev->channel, buffer, bufferlen,
+ &bytes_recvd, &req_id);
+
+ switch (ret) {
+ case 0:
+ /*
+ * 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_INVALIDATE_BLOCK:
+
+ inval = (struct pci_dev_inval_block *)buffer;
+ hpdev = lookup_hv_pcidev(hbus,
+ inval->slot.slot);
+ if (hpdev) {
+ if (hpdev->block_invalidate) {
+ hpdev->block_invalidate(
+ hpdev->invalidate_context,
+ inval->block_mask);
+ }
+ hv_pcichild_dec(hpdev,
+ hv_pcidev_ref_by_slot);
+ }
+ break;
+
+ case PCI_EJECT:
+
+ dev_message = (struct pci_dev_incoming *)buffer;
+ hpdev = lookup_hv_pcidev(hbus,
+ dev_message->slot.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;
+
+ case -ENOBUFS:
+ kfree(buffer);
+ /* Handle large packet */
+ bufferlen = bytes_recvd;
+ buffer = kmalloc(bytes_recvd, GFP_ATOMIC);
+ if (!buffer)
+ return;
+
+ break;
+ }
+ } while (1);
+}
+
+/**
+ * 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 protocol_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 protocol_exit;
+ }
+
+ ret = 0;
+
+protocol_exit:
+
+ kfree(pkt);
+ return ret;
+}
+
+static void hv_pci_free_bridge_windows(struct hv_pcibus_device *hbus)
+{
+ if (hbus->low_mmio_space && hbus->low_mmio_res)
+ release_mem_region(hbus->low_mmio_res->start,
+ hbus->low_mmio_res->end -
+ hbus->low_mmio_res->start + 1);
+
+ if (hbus->high_mmio_space && hbus->high_mmio_res)
+ release_mem_region(hbus->high_mmio_res->start,
+ hbus->high_mmio_res->end -
+ hbus->high_mmio_res->start + 1);
+}
+
+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;
+
+ 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:
+
+ hv_pci_free_bridge_windows(hbus);
+ return ret;
+}
+
+static int hv_pci_d0_entry(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 d0_entry_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 d0_entry_exit;
+ }
+
+ ret = 0;
+
+d0_entry_exit:
+
+ kfree(pkt);
+ return ret;
+}
+
+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)) {
+ 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;
+ } else
+ return -ENOTEMPTY;
+}
+
+/**
+ * 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.
+ *
+ * @param hdev - The device associated with this virtual PCI
+ * front-end
+ *
+ * @return int
+ */
+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 slot;
+ int ret;
+
+ pkt = kmalloc(sizeof(*pkt) + sizeof(*res_assigned), GFP_KERNEL);
+ if (!pkt)
+ return -ENOMEM;
+
+ for (slot = 0; slot < 256; slot++) {
+ hpdev = lookup_hv_pcidev(hbus, slot);
+ if (hpdev) {
+ 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->slot.slot = hpdev->desc.s_no.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)
+ goto send_resources_allocated_free;
+
+ 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);
+ goto send_resources_allocated_free;
+ }
+ }
+ }
+ ret = 0;
+
+send_resources_allocated_free:
+
+ kfree(pkt);
+ return ret;
+}
+
+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 slot;
+ int ret;
+
+ for (slot = 0; slot < 256; slot++) {
+ hpdev = lookup_hv_pcidev(hbus, slot);
+ if (hpdev) {
+ memset(&pkt, 0, sizeof(pkt));
+ pkt.message_type = PCI_RESOURCES_RELEASED;
+ pkt.slot.slot = hpdev->desc.s_no.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)
+{
+ atomic_inc(&hbus->remove_lock);
+}
+
+static void hv_pcibus_dec(struct hv_pcibus_device *hbus)
+{
+ if (atomic_dec_and_test(&hbus->remove_lock))
+ complete(&hbus->remove_event);
+}
+
+/**
+ * This function is called as part of the VMBus probe routine.
+ *
+ * @param hdev - VMBus representation of the device
+ * @param dev_id - Indentifies the device itself
+ *
+ * @return int
+ */
+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 = devm_kzalloc(&hdev->device, sizeof(*hbus), GFP_KERNEL);
+ if (!hbus)
+ return -ENOMEM;
+
+ pr_devel("New virtual PCIe bus: %p\n", hbus);
+
+ hbus->hdev = hdev;
+ 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);
+ hv_pcibus_inc(hbus);
+
+ /*
+ * 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)
+ return ret;
+
+ hv_set_drvdata(hdev, hbus);
+
+ ret = hv_pci_protocol_negotiation(hdev);
+ if (ret)
+ goto probe_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 probe_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 probe_release;
+ }
+
+ ret = hv_pci_query_relations(hdev);
+ if (ret)
+ goto probe_unmap;
+
+ ret = hv_pci_d0_entry(hdev);
+ if (ret)
+ goto probe_unmap;
+
+ ret = hv_pci_allocate_bridge_windows(hbus);
+ if (ret)
+ goto probe_unmap;
+
+ ret = hv_send_resources_allocated(hdev);
+ if (ret)
+ goto probe_unmap;
+
+ prepopulate_bars(hbus);
+
+ hbus->state = hv_pcibus_probed;
+
+ ret = create_root_hv_pci_bus(hbus);
+ if (ret)
+ goto probe_free_windows;
+ return 0;
+
+probe_free_windows:
+ hv_pci_free_bridge_windows(hbus);
+probe_unmap:
+ iounmap(hbus->cfg_addr);
+probe_release:
+ release_mem_region(hbus->mem_config->start, PCI_CONFIG_MMIO_LENGTH);
+probe_close:
+ vmbus_close(hdev->channel);
+ return ret;
+}
+
+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, 5*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);
+ hv_pci_free_bridge_windows(hbus);
+ pci_free_resource_list(&hbus->resources_for_children);
+ hv_pcibus_dec(hbus);
+ wait_for_completion(&hbus->remove_event);
+ 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_hv_pci_drv(void)
+{
+ vmbus_driver_unregister(&hv_pci_drv);
+ hyperv_uninstall_interrupt_translation();
+}
+
+static int __init init_hv_pci_drv(void)
+{
+ int ret;
+
+ hv_msi.setup_msi_irqs = hv_setup_msi_irqs;
+ hv_msi.compose_msi_msg = hv_compose_msi_msg;
+ hv_msi.teardown_msi_irqs = hv_teardown_msi_irqs;
+ hv_msi.restore_msi_irqs = hv_restore_msi_irqs;
+
+ /*
+ * Hook the MSI management functions so that interrupts can be
+ * remapped through the hypervisor.
+ */
+
+ hyperv_install_interrupt_translation(&hv_msi);
+
+ /* Register this driver with VMBus. */
+ ret = vmbus_driver_register(&hv_pci_drv);
+
+ if (ret < 0)
+ exit_hv_pci_drv();
+
+ return ret;
+}
+
+module_init(init_hv_pci_drv);
+module_exit(exit_hv_pci_drv);
+
+MODULE_DESCRIPTION("Hyper-V PCI");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h
index 1903238..0acf9ff 100644
--- a/include/linux/hyperv.h
+++ b/include/linux/hyperv.h
@@ -1269,4 +1269,22 @@ void hv_process_channel_removal(struct vmbus_channel *channel, u32 relid);

extern __u32 vmbus_proto_version;

+/*
+ * Functions for passing data between SR-IOV PF and VF drivers. The VF driver
+ * sends requests to read and write blocks. Each block must be 128 bytes or
+ * smaller so that the host can guarantee a successful response. (All
+ * intermediate buffers are preallocated.) Optionally, the VF driver can
+ * register a callback function which will be invoked when the host says that
+ * one or more of the first 64 block IDs is "invalid" which means that the
+ * VF driver should reread them.
+ */
+#define CONFIG_BLOCK_SIZE_MAX 128
+int hv_read_config_block(struct pci_dev *dev, void *buf, int buf_len,
+ int block_id, int *bytes_returned);
+int hv_write_config_block(struct pci_dev *dev, void *buf, int len,
+ int block_id);
+int hv_register_block_invalidate(struct pci_dev *dev, void *context,
+ void (*block_invalidate)(void *context,
+ u64 block_mask));
+
#endif /* _HYPERV_H */
--
1.9.1

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