4116 lines
		
	
	
		
			114 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			4116 lines
		
	
	
		
			114 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0
 | |
| /*
 | |
|  * Copyright (c) Microsoft Corporation.
 | |
|  *
 | |
|  * Author:
 | |
|  *   Jake Oshins <jakeo@microsoft.com>
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|  *
 | |
|  * This driver acts as a paravirtual front-end for PCI Express root buses.
 | |
|  * When a PCI Express function (either an entire device or an SR-IOV
 | |
|  * Virtual Function) is being passed through to the VM, this driver exposes
 | |
|  * a new bus to the guest VM.  This is modeled as a root PCI bus because
 | |
|  * no bridges are being exposed to the VM.  In fact, with a "Generation 2"
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|  * VM within Hyper-V, there may seem to be no PCI bus at all in the VM
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|  * until a device as been exposed using this driver.
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|  *
 | |
|  * Each root PCI bus has its own PCI domain, which is called "Segment" in
 | |
|  * the PCI Firmware Specifications.  Thus while each device passed through
 | |
|  * to the VM using this front-end will appear at "device 0", the domain will
 | |
|  * be unique.  Typically, each bus will have one PCI function on it, though
 | |
|  * this driver does support more than one.
 | |
|  *
 | |
|  * In order to map the interrupts from the device through to the guest VM,
 | |
|  * this driver also implements an IRQ Domain, which handles interrupts (either
 | |
|  * MSI or MSI-X) associated with the functions on the bus.  As interrupts are
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|  * set up, torn down, or reaffined, this driver communicates with the
 | |
|  * underlying hypervisor to adjust the mappings in the I/O MMU so that each
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|  * interrupt will be delivered to the correct virtual processor at the right
 | |
|  * vector.  This driver does not support level-triggered (line-based)
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|  * interrupts, and will report that the Interrupt Line register in the
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|  * function's configuration space is zero.
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|  *
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|  * The rest of this driver mostly maps PCI concepts onto underlying Hyper-V
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|  * facilities.  For instance, the configuration space of a function exposed
 | |
|  * by Hyper-V is mapped into a single page of memory space, and the
 | |
|  * read and write handlers for config space must be aware of this mechanism.
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|  * Similarly, device setup and teardown involves messages sent to and from
 | |
|  * the PCI back-end driver in Hyper-V.
 | |
|  */
 | |
| 
 | |
| #include <linux/kernel.h>
 | |
| #include <linux/module.h>
 | |
| #include <linux/pci.h>
 | |
| #include <linux/pci-ecam.h>
 | |
| #include <linux/delay.h>
 | |
| #include <linux/semaphore.h>
 | |
| #include <linux/irq.h>
 | |
| #include <linux/msi.h>
 | |
| #include <linux/hyperv.h>
 | |
| #include <linux/refcount.h>
 | |
| #include <linux/irqdomain.h>
 | |
| #include <linux/acpi.h>
 | |
| #include <linux/sizes.h>
 | |
| #include <asm/mshyperv.h>
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| 
 | |
| /*
 | |
|  * 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_t {
 | |
| 	PCI_PROTOCOL_VERSION_1_1 = PCI_MAKE_VERSION(1, 1),	/* Win10 */
 | |
| 	PCI_PROTOCOL_VERSION_1_2 = PCI_MAKE_VERSION(1, 2),	/* RS1 */
 | |
| 	PCI_PROTOCOL_VERSION_1_3 = PCI_MAKE_VERSION(1, 3),	/* Vibranium */
 | |
| 	PCI_PROTOCOL_VERSION_1_4 = PCI_MAKE_VERSION(1, 4),	/* WS2022 */
 | |
| };
 | |
| 
 | |
| #define CPU_AFFINITY_ALL	-1ULL
 | |
| 
 | |
| /*
 | |
|  * Supported protocol versions in the order of probing - highest go
 | |
|  * first.
 | |
|  */
 | |
| static enum pci_protocol_version_t pci_protocol_versions[] = {
 | |
| 	PCI_PROTOCOL_VERSION_1_4,
 | |
| 	PCI_PROTOCOL_VERSION_1_3,
 | |
| 	PCI_PROTOCOL_VERSION_1_2,
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| 	PCI_PROTOCOL_VERSION_1_1,
 | |
| };
 | |
| 
 | |
| #define PCI_CONFIG_MMIO_LENGTH	0x2000
 | |
| #define CFG_PAGE_OFFSET 0x1000
 | |
| #define CFG_PAGE_SIZE (PCI_CONFIG_MMIO_LENGTH - CFG_PAGE_OFFSET)
 | |
| 
 | |
| #define MAX_SUPPORTED_MSI_MESSAGES 0x400
 | |
| 
 | |
| #define STATUS_REVISION_MISMATCH 0xC0000059
 | |
| 
 | |
| /* space for 32bit serial number as string */
 | |
| #define SLOT_NAME_SIZE 11
 | |
| 
 | |
| /*
 | |
|  * Size of requestor for VMbus; the value is based on the observation
 | |
|  * that having more than one request outstanding is 'rare', and so 64
 | |
|  * should be generous in ensuring that we don't ever run out.
 | |
|  */
 | |
| #define HV_PCI_RQSTOR_SIZE 64
 | |
| 
 | |
| /*
 | |
|  * 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,
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| 	PCI_RESOURCES_ASSIGNED2		= PCI_MESSAGE_BASE + 0x16,
 | |
| 	PCI_CREATE_INTERRUPT_MESSAGE2	= PCI_MESSAGE_BASE + 0x17,
 | |
| 	PCI_DELETE_INTERRUPT_MESSAGE2	= PCI_MESSAGE_BASE + 0x18, /* unused */
 | |
| 	PCI_BUS_RELATIONS2		= PCI_MESSAGE_BASE + 0x19,
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| 	PCI_RESOURCES_ASSIGNED3         = PCI_MESSAGE_BASE + 0x1A,
 | |
| 	PCI_CREATE_INTERRUPT_MESSAGE3   = PCI_MESSAGE_BASE + 0x1B,
 | |
| 	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	dev:5;
 | |
| 		u32	func:3;
 | |
| 		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;
 | |
| 
 | |
| enum pci_device_description_flags {
 | |
| 	HV_PCI_DEVICE_FLAG_NONE			= 0x0,
 | |
| 	HV_PCI_DEVICE_FLAG_NUMA_AFFINITY	= 0x1,
 | |
| };
 | |
| 
 | |
| struct pci_function_description2 {
 | |
| 	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 */
 | |
| 	u32	flags;
 | |
| 	u16	virtual_numa_node;
 | |
| 	u16	reserved;
 | |
| } __packed;
 | |
| 
 | |
| /**
 | |
|  * struct hv_msi_desc
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|  * @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
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|  *			Interrupt. For "MSI", as first defined
 | |
|  *			in PCI 2.2, this can be between 1 and
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|  *			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
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|  * @cpu_mask:		All the target virtual processors.
 | |
|  */
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| struct hv_msi_desc {
 | |
| 	u8	vector;
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| 	u8	delivery_mode;
 | |
| 	u16	vector_count;
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| 	u32	reserved;
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| 	u64	cpu_mask;
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| } __packed;
 | |
| 
 | |
| /**
 | |
|  * struct hv_msi_desc2 - 1.2 version of 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.
 | |
|  * @processor_count:	number of bits enabled in array.
 | |
|  * @processor_array:	All the target virtual processors.
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|  */
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| struct hv_msi_desc2 {
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| 	u8	vector;
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| 	u8	delivery_mode;
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| 	u16	vector_count;
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| 	u16	processor_count;
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| 	u16	processor_array[32];
 | |
| } __packed;
 | |
| 
 | |
| /*
 | |
|  * struct hv_msi_desc3 - 1.3 version of hv_msi_desc
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|  *	Everything is the same as in 'hv_msi_desc2' except that the size of the
 | |
|  *	'vector' field is larger to support bigger vector values. For ex: LPI
 | |
|  *	vectors on ARM.
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|  */
 | |
| struct hv_msi_desc3 {
 | |
| 	u32	vector;
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| 	u8	delivery_mode;
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| 	u8	reserved;
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| 	u16	vector_count;
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| 	u16	processor_count;
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| 	u16	processor_array[32];
 | |
| } __packed;
 | |
| 
 | |
| /**
 | |
|  * struct tran_int_desc
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|  * @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.
 | |
|  */
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| struct tran_int_desc {
 | |
| 	u16	reserved;
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| 	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 type;
 | |
| } __packed;
 | |
| 
 | |
| struct pci_child_message {
 | |
| 	struct pci_message 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;
 | |
| 	u32 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[];
 | |
| } __packed;
 | |
| 
 | |
| struct pci_bus_relations2 {
 | |
| 	struct pci_incoming_message incoming;
 | |
| 	u32 device_count;
 | |
| 	struct pci_function_description2 func[];
 | |
| } __packed;
 | |
| 
 | |
| struct pci_q_res_req_response {
 | |
| 	struct vmpacket_descriptor hdr;
 | |
| 	s32 status;			/* negative values are failures */
 | |
| 	u32 probed_bar[PCI_STD_NUM_BARS];
 | |
| } __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_resources_assigned2 {
 | |
| 	struct pci_message message_type;
 | |
| 	union win_slot_encoding wslot;
 | |
| 	u8 memory_range[0x14][6];	/* not used here */
 | |
| 	u32 msi_descriptor_count;
 | |
| 	u8 reserved[70];
 | |
| } __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_create_interrupt2 {
 | |
| 	struct pci_message message_type;
 | |
| 	union win_slot_encoding wslot;
 | |
| 	struct hv_msi_desc2 int_desc;
 | |
| } __packed;
 | |
| 
 | |
| struct pci_create_interrupt3 {
 | |
| 	struct pci_message message_type;
 | |
| 	union win_slot_encoding wslot;
 | |
| 	struct hv_msi_desc3 int_desc;
 | |
| } __packed;
 | |
| 
 | |
| struct pci_delete_interrupt {
 | |
| 	struct pci_message message_type;
 | |
| 	union win_slot_encoding wslot;
 | |
| 	struct tran_int_desc int_desc;
 | |
| } __packed;
 | |
| 
 | |
| /*
 | |
|  * Note: the VM must pass a valid block id, wslot and bytes_requested.
 | |
|  */
 | |
| struct pci_read_block {
 | |
| 	struct pci_message message_type;
 | |
| 	u32 block_id;
 | |
| 	union win_slot_encoding wslot;
 | |
| 	u32 bytes_requested;
 | |
| } __packed;
 | |
| 
 | |
| struct pci_read_block_response {
 | |
| 	struct vmpacket_descriptor hdr;
 | |
| 	u32 status;
 | |
| 	u8 bytes[HV_CONFIG_BLOCK_SIZE_MAX];
 | |
| } __packed;
 | |
| 
 | |
| /*
 | |
|  * Note: the VM must pass a valid block id, wslot and byte_count.
 | |
|  */
 | |
| struct pci_write_block {
 | |
| 	struct pci_message message_type;
 | |
| 	u32 block_id;
 | |
| 	union win_slot_encoding wslot;
 | |
| 	u32 byte_count;
 | |
| 	u8 bytes[HV_CONFIG_BLOCK_SIZE_MAX];
 | |
| } __packed;
 | |
| 
 | |
| struct pci_dev_inval_block {
 | |
| 	struct pci_incoming_message incoming;
 | |
| 	union win_slot_encoding wslot;
 | |
| 	u64 block_mask;
 | |
| } __packed;
 | |
| 
 | |
| struct pci_dev_incoming {
 | |
| 	struct pci_incoming_message incoming;
 | |
| 	union win_slot_encoding wslot;
 | |
| } __packed;
 | |
| 
 | |
| struct pci_eject_response {
 | |
| 	struct pci_message message_type;
 | |
| 	union win_slot_encoding wslot;
 | |
| 	u32 status;
 | |
| } __packed;
 | |
| 
 | |
| static int pci_ring_size = VMBUS_RING_SIZE(SZ_16K);
 | |
| 
 | |
| /*
 | |
|  * Driver specific state.
 | |
|  */
 | |
| 
 | |
| enum hv_pcibus_state {
 | |
| 	hv_pcibus_init = 0,
 | |
| 	hv_pcibus_probed,
 | |
| 	hv_pcibus_installed,
 | |
| 	hv_pcibus_removing,
 | |
| 	hv_pcibus_maximum
 | |
| };
 | |
| 
 | |
| struct hv_pcibus_device {
 | |
| #ifdef CONFIG_X86
 | |
| 	struct pci_sysdata sysdata;
 | |
| #elif defined(CONFIG_ARM64)
 | |
| 	struct pci_config_window sysdata;
 | |
| #endif
 | |
| 	struct pci_host_bridge *bridge;
 | |
| 	struct fwnode_handle *fwnode;
 | |
| 	/* Protocol version negotiated with the host */
 | |
| 	enum pci_protocol_version_t protocol_version;
 | |
| 
 | |
| 	struct mutex state_lock;
 | |
| 	enum hv_pcibus_state state;
 | |
| 
 | |
| 	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 pci_bus *pci_bus;
 | |
| 	spinlock_t config_lock;	/* Avoid two threads writing index page */
 | |
| 	spinlock_t device_list_lock;	/* Protect lists below */
 | |
| 	void __iomem *cfg_addr;
 | |
| 
 | |
| 	struct list_head children;
 | |
| 	struct list_head dr_list;
 | |
| 
 | |
| 	struct msi_domain_info msi_info;
 | |
| 	struct irq_domain *irq_domain;
 | |
| 
 | |
| 	struct workqueue_struct *wq;
 | |
| 
 | |
| 	/* Highest slot of child device with resources allocated */
 | |
| 	int wslot_res_allocated;
 | |
| 	bool use_calls; /* Use hypercalls to access mmio cfg space */
 | |
| };
 | |
| 
 | |
| /*
 | |
|  * 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_pcidev_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 */
 | |
| 	u32	flags;
 | |
| 	u16	virtual_numa_node;
 | |
| };
 | |
| 
 | |
| struct hv_dr_state {
 | |
| 	struct list_head list_entry;
 | |
| 	u32 device_count;
 | |
| 	struct hv_pcidev_description func[] __counted_by(device_count);
 | |
| };
 | |
| 
 | |
| struct hv_pci_dev {
 | |
| 	/* List protected by pci_rescan_remove_lock */
 | |
| 	struct list_head list_entry;
 | |
| 	refcount_t refs;
 | |
| 	struct pci_slot *pci_slot;
 | |
| 	struct hv_pcidev_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;
 | |
| 
 | |
| 	/*
 | |
| 	 * 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[PCI_STD_NUM_BARS];
 | |
| };
 | |
| 
 | |
| struct hv_pci_compl {
 | |
| 	struct completion host_event;
 | |
| 	s32 completion_status;
 | |
| };
 | |
| 
 | |
| static void hv_pci_onchannelcallback(void *context);
 | |
| 
 | |
| #ifdef CONFIG_X86
 | |
| #define DELIVERY_MODE	APIC_DELIVERY_MODE_FIXED
 | |
| #define FLOW_HANDLER	handle_edge_irq
 | |
| #define FLOW_NAME	"edge"
 | |
| 
 | |
| static int hv_pci_irqchip_init(void)
 | |
| {
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static struct irq_domain *hv_pci_get_root_domain(void)
 | |
| {
 | |
| 	return x86_vector_domain;
 | |
| }
 | |
| 
 | |
| static unsigned int hv_msi_get_int_vector(struct irq_data *data)
 | |
| {
 | |
| 	struct irq_cfg *cfg = irqd_cfg(data);
 | |
| 
 | |
| 	return cfg->vector;
 | |
| }
 | |
| 
 | |
| #define hv_msi_prepare		pci_msi_prepare
 | |
| 
 | |
| /**
 | |
|  * hv_arch_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.
 | |
|  */
 | |
| static void hv_arch_irq_unmask(struct irq_data *data)
 | |
| {
 | |
| 	struct msi_desc *msi_desc = irq_data_get_msi_desc(data);
 | |
| 	struct hv_retarget_device_interrupt *params;
 | |
| 	struct tran_int_desc *int_desc;
 | |
| 	struct hv_pcibus_device *hbus;
 | |
| 	const struct cpumask *dest;
 | |
| 	cpumask_var_t tmp;
 | |
| 	struct pci_bus *pbus;
 | |
| 	struct pci_dev *pdev;
 | |
| 	unsigned long flags;
 | |
| 	u32 var_size = 0;
 | |
| 	int cpu, nr_bank;
 | |
| 	u64 res;
 | |
| 
 | |
| 	dest = irq_data_get_effective_affinity_mask(data);
 | |
| 	pdev = msi_desc_to_pci_dev(msi_desc);
 | |
| 	pbus = pdev->bus;
 | |
| 	hbus = container_of(pbus->sysdata, struct hv_pcibus_device, sysdata);
 | |
| 	int_desc = data->chip_data;
 | |
| 	if (!int_desc) {
 | |
| 		dev_warn(&hbus->hdev->device, "%s() can not unmask irq %u\n",
 | |
| 			 __func__, data->irq);
 | |
| 		return;
 | |
| 	}
 | |
| 
 | |
| 	local_irq_save(flags);
 | |
| 
 | |
| 	params = *this_cpu_ptr(hyperv_pcpu_input_arg);
 | |
| 	memset(params, 0, sizeof(*params));
 | |
| 	params->partition_id = HV_PARTITION_ID_SELF;
 | |
| 	params->int_entry.source = HV_INTERRUPT_SOURCE_MSI;
 | |
| 	params->int_entry.msi_entry.address.as_uint32 = int_desc->address & 0xffffffff;
 | |
| 	params->int_entry.msi_entry.data.as_uint32 = int_desc->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->int_target.vector = hv_msi_get_int_vector(data);
 | |
| 
 | |
| 	if (hbus->protocol_version >= PCI_PROTOCOL_VERSION_1_2) {
 | |
| 		/*
 | |
| 		 * PCI_PROTOCOL_VERSION_1_2 supports the VP_SET version of the
 | |
| 		 * HVCALL_RETARGET_INTERRUPT hypercall, which also coincides
 | |
| 		 * with >64 VP support.
 | |
| 		 * ms_hyperv.hints & HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED
 | |
| 		 * is not sufficient for this hypercall.
 | |
| 		 */
 | |
| 		params->int_target.flags |=
 | |
| 			HV_DEVICE_INTERRUPT_TARGET_PROCESSOR_SET;
 | |
| 
 | |
| 		if (!alloc_cpumask_var(&tmp, GFP_ATOMIC)) {
 | |
| 			res = 1;
 | |
| 			goto out;
 | |
| 		}
 | |
| 
 | |
| 		cpumask_and(tmp, dest, cpu_online_mask);
 | |
| 		nr_bank = cpumask_to_vpset(¶ms->int_target.vp_set, tmp);
 | |
| 		free_cpumask_var(tmp);
 | |
| 
 | |
| 		if (nr_bank <= 0) {
 | |
| 			res = 1;
 | |
| 			goto out;
 | |
| 		}
 | |
| 
 | |
| 		/*
 | |
| 		 * var-sized hypercall, var-size starts after vp_mask (thus
 | |
| 		 * vp_set.format does not count, but vp_set.valid_bank_mask
 | |
| 		 * does).
 | |
| 		 */
 | |
| 		var_size = 1 + nr_bank;
 | |
| 	} else {
 | |
| 		for_each_cpu_and(cpu, dest, cpu_online_mask) {
 | |
| 			params->int_target.vp_mask |=
 | |
| 				(1ULL << hv_cpu_number_to_vp_number(cpu));
 | |
| 		}
 | |
| 	}
 | |
| 
 | |
| 	res = hv_do_hypercall(HVCALL_RETARGET_INTERRUPT | (var_size << 17),
 | |
| 			      params, NULL);
 | |
| 
 | |
| out:
 | |
| 	local_irq_restore(flags);
 | |
| 
 | |
| 	/*
 | |
| 	 * During hibernation, when a CPU is offlined, the kernel tries
 | |
| 	 * to move the interrupt to the remaining CPUs that haven't
 | |
| 	 * been offlined yet. In this case, the below hv_do_hypercall()
 | |
| 	 * always fails since the vmbus channel has been closed:
 | |
| 	 * refer to cpu_disable_common() -> fixup_irqs() ->
 | |
| 	 * irq_migrate_all_off_this_cpu() -> migrate_one_irq().
 | |
| 	 *
 | |
| 	 * Suppress the error message for hibernation because the failure
 | |
| 	 * during hibernation does not matter (at this time all the devices
 | |
| 	 * have been frozen). Note: the correct affinity info is still updated
 | |
| 	 * into the irqdata data structure in migrate_one_irq() ->
 | |
| 	 * irq_do_set_affinity(), so later when the VM resumes,
 | |
| 	 * hv_pci_restore_msi_state() is able to correctly restore the
 | |
| 	 * interrupt with the correct affinity.
 | |
| 	 */
 | |
| 	if (!hv_result_success(res) && hbus->state != hv_pcibus_removing)
 | |
| 		dev_err(&hbus->hdev->device,
 | |
| 			"%s() failed: %#llx", __func__, res);
 | |
| }
 | |
| #elif defined(CONFIG_ARM64)
 | |
| /*
 | |
|  * SPI vectors to use for vPCI; arch SPIs range is [32, 1019], but leaving a bit
 | |
|  * of room at the start to allow for SPIs to be specified through ACPI and
 | |
|  * starting with a power of two to satisfy power of 2 multi-MSI requirement.
 | |
|  */
 | |
| #define HV_PCI_MSI_SPI_START	64
 | |
| #define HV_PCI_MSI_SPI_NR	(1020 - HV_PCI_MSI_SPI_START)
 | |
| #define DELIVERY_MODE		0
 | |
| #define FLOW_HANDLER		NULL
 | |
| #define FLOW_NAME		NULL
 | |
| #define hv_msi_prepare		NULL
 | |
| 
 | |
| struct hv_pci_chip_data {
 | |
| 	DECLARE_BITMAP(spi_map, HV_PCI_MSI_SPI_NR);
 | |
| 	struct mutex	map_lock;
 | |
| };
 | |
| 
 | |
| /* Hyper-V vPCI MSI GIC IRQ domain */
 | |
| static struct irq_domain *hv_msi_gic_irq_domain;
 | |
| 
 | |
| /* Hyper-V PCI MSI IRQ chip */
 | |
| static struct irq_chip hv_arm64_msi_irq_chip = {
 | |
| 	.name = "MSI",
 | |
| 	.irq_set_affinity = irq_chip_set_affinity_parent,
 | |
| 	.irq_eoi = irq_chip_eoi_parent,
 | |
| 	.irq_mask = irq_chip_mask_parent,
 | |
| 	.irq_unmask = irq_chip_unmask_parent
 | |
| };
 | |
| 
 | |
| static unsigned int hv_msi_get_int_vector(struct irq_data *irqd)
 | |
| {
 | |
| 	return irqd->parent_data->hwirq;
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * @nr_bm_irqs:		Indicates the number of IRQs that were allocated from
 | |
|  *			the bitmap.
 | |
|  * @nr_dom_irqs:	Indicates the number of IRQs that were allocated from
 | |
|  *			the parent domain.
 | |
|  */
 | |
| static void hv_pci_vec_irq_free(struct irq_domain *domain,
 | |
| 				unsigned int virq,
 | |
| 				unsigned int nr_bm_irqs,
 | |
| 				unsigned int nr_dom_irqs)
 | |
| {
 | |
| 	struct hv_pci_chip_data *chip_data = domain->host_data;
 | |
| 	struct irq_data *d = irq_domain_get_irq_data(domain, virq);
 | |
| 	int first = d->hwirq - HV_PCI_MSI_SPI_START;
 | |
| 	int i;
 | |
| 
 | |
| 	mutex_lock(&chip_data->map_lock);
 | |
| 	bitmap_release_region(chip_data->spi_map,
 | |
| 			      first,
 | |
| 			      get_count_order(nr_bm_irqs));
 | |
| 	mutex_unlock(&chip_data->map_lock);
 | |
| 	for (i = 0; i < nr_dom_irqs; i++) {
 | |
| 		if (i)
 | |
| 			d = irq_domain_get_irq_data(domain, virq + i);
 | |
| 		irq_domain_reset_irq_data(d);
 | |
| 	}
 | |
| 
 | |
| 	irq_domain_free_irqs_parent(domain, virq, nr_dom_irqs);
 | |
| }
 | |
| 
 | |
| static void hv_pci_vec_irq_domain_free(struct irq_domain *domain,
 | |
| 				       unsigned int virq,
 | |
| 				       unsigned int nr_irqs)
 | |
| {
 | |
| 	hv_pci_vec_irq_free(domain, virq, nr_irqs, nr_irqs);
 | |
| }
 | |
| 
 | |
| static int hv_pci_vec_alloc_device_irq(struct irq_domain *domain,
 | |
| 				       unsigned int nr_irqs,
 | |
| 				       irq_hw_number_t *hwirq)
 | |
| {
 | |
| 	struct hv_pci_chip_data *chip_data = domain->host_data;
 | |
| 	int index;
 | |
| 
 | |
| 	/* Find and allocate region from the SPI bitmap */
 | |
| 	mutex_lock(&chip_data->map_lock);
 | |
| 	index = bitmap_find_free_region(chip_data->spi_map,
 | |
| 					HV_PCI_MSI_SPI_NR,
 | |
| 					get_count_order(nr_irqs));
 | |
| 	mutex_unlock(&chip_data->map_lock);
 | |
| 	if (index < 0)
 | |
| 		return -ENOSPC;
 | |
| 
 | |
| 	*hwirq = index + HV_PCI_MSI_SPI_START;
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static int hv_pci_vec_irq_gic_domain_alloc(struct irq_domain *domain,
 | |
| 					   unsigned int virq,
 | |
| 					   irq_hw_number_t hwirq)
 | |
| {
 | |
| 	struct irq_fwspec fwspec;
 | |
| 	struct irq_data *d;
 | |
| 	int ret;
 | |
| 
 | |
| 	fwspec.fwnode = domain->parent->fwnode;
 | |
| 	fwspec.param_count = 2;
 | |
| 	fwspec.param[0] = hwirq;
 | |
| 	fwspec.param[1] = IRQ_TYPE_EDGE_RISING;
 | |
| 
 | |
| 	ret = irq_domain_alloc_irqs_parent(domain, virq, 1, &fwspec);
 | |
| 	if (ret)
 | |
| 		return ret;
 | |
| 
 | |
| 	/*
 | |
| 	 * Since the interrupt specifier is not coming from ACPI or DT, the
 | |
| 	 * trigger type will need to be set explicitly. Otherwise, it will be
 | |
| 	 * set to whatever is in the GIC configuration.
 | |
| 	 */
 | |
| 	d = irq_domain_get_irq_data(domain->parent, virq);
 | |
| 
 | |
| 	return d->chip->irq_set_type(d, IRQ_TYPE_EDGE_RISING);
 | |
| }
 | |
| 
 | |
| static int hv_pci_vec_irq_domain_alloc(struct irq_domain *domain,
 | |
| 				       unsigned int virq, unsigned int nr_irqs,
 | |
| 				       void *args)
 | |
| {
 | |
| 	irq_hw_number_t hwirq;
 | |
| 	unsigned int i;
 | |
| 	int ret;
 | |
| 
 | |
| 	ret = hv_pci_vec_alloc_device_irq(domain, nr_irqs, &hwirq);
 | |
| 	if (ret)
 | |
| 		return ret;
 | |
| 
 | |
| 	for (i = 0; i < nr_irqs; i++) {
 | |
| 		ret = hv_pci_vec_irq_gic_domain_alloc(domain, virq + i,
 | |
| 						      hwirq + i);
 | |
| 		if (ret) {
 | |
| 			hv_pci_vec_irq_free(domain, virq, nr_irqs, i);
 | |
| 			return ret;
 | |
| 		}
 | |
| 
 | |
| 		irq_domain_set_hwirq_and_chip(domain, virq + i,
 | |
| 					      hwirq + i,
 | |
| 					      &hv_arm64_msi_irq_chip,
 | |
| 					      domain->host_data);
 | |
| 		pr_debug("pID:%d vID:%u\n", (int)(hwirq + i), virq + i);
 | |
| 	}
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Pick the first cpu as the irq affinity that can be temporarily used for
 | |
|  * composing MSI from the hypervisor. GIC will eventually set the right
 | |
|  * affinity for the irq and the 'unmask' will retarget the interrupt to that
 | |
|  * cpu.
 | |
|  */
 | |
| static int hv_pci_vec_irq_domain_activate(struct irq_domain *domain,
 | |
| 					  struct irq_data *irqd, bool reserve)
 | |
| {
 | |
| 	int cpu = cpumask_first(cpu_present_mask);
 | |
| 
 | |
| 	irq_data_update_effective_affinity(irqd, cpumask_of(cpu));
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static const struct irq_domain_ops hv_pci_domain_ops = {
 | |
| 	.alloc	= hv_pci_vec_irq_domain_alloc,
 | |
| 	.free	= hv_pci_vec_irq_domain_free,
 | |
| 	.activate = hv_pci_vec_irq_domain_activate,
 | |
| };
 | |
| 
 | |
| static int hv_pci_irqchip_init(void)
 | |
| {
 | |
| 	static struct hv_pci_chip_data *chip_data;
 | |
| 	struct fwnode_handle *fn = NULL;
 | |
| 	int ret = -ENOMEM;
 | |
| 
 | |
| 	chip_data = kzalloc(sizeof(*chip_data), GFP_KERNEL);
 | |
| 	if (!chip_data)
 | |
| 		return ret;
 | |
| 
 | |
| 	mutex_init(&chip_data->map_lock);
 | |
| 	fn = irq_domain_alloc_named_fwnode("hv_vpci_arm64");
 | |
| 	if (!fn)
 | |
| 		goto free_chip;
 | |
| 
 | |
| 	/*
 | |
| 	 * IRQ domain once enabled, should not be removed since there is no
 | |
| 	 * way to ensure that all the corresponding devices are also gone and
 | |
| 	 * no interrupts will be generated.
 | |
| 	 */
 | |
| 	hv_msi_gic_irq_domain = acpi_irq_create_hierarchy(0, HV_PCI_MSI_SPI_NR,
 | |
| 							  fn, &hv_pci_domain_ops,
 | |
| 							  chip_data);
 | |
| 
 | |
| 	if (!hv_msi_gic_irq_domain) {
 | |
| 		pr_err("Failed to create Hyper-V arm64 vPCI MSI IRQ domain\n");
 | |
| 		goto free_chip;
 | |
| 	}
 | |
| 
 | |
| 	return 0;
 | |
| 
 | |
| free_chip:
 | |
| 	kfree(chip_data);
 | |
| 	if (fn)
 | |
| 		irq_domain_free_fwnode(fn);
 | |
| 
 | |
| 	return ret;
 | |
| }
 | |
| 
 | |
| static struct irq_domain *hv_pci_get_root_domain(void)
 | |
| {
 | |
| 	return hv_msi_gic_irq_domain;
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * SPIs are used for interrupts of PCI devices and SPIs is managed via GICD
 | |
|  * registers which Hyper-V already supports, so no hypercall needed.
 | |
|  */
 | |
| static void hv_arch_irq_unmask(struct irq_data *data) { }
 | |
| #endif /* CONFIG_ARM64 */
 | |
| 
 | |
| /**
 | |
|  * 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;
 | |
| 
 | |
| 	comp_pkt->completion_status = resp->status;
 | |
| 	complete(&comp_pkt->host_event);
 | |
| }
 | |
| 
 | |
| static struct hv_pci_dev *get_pcichild_wslot(struct hv_pcibus_device *hbus,
 | |
| 						u32 wslot);
 | |
| 
 | |
| static void get_pcichild(struct hv_pci_dev *hpdev)
 | |
| {
 | |
| 	refcount_inc(&hpdev->refs);
 | |
| }
 | |
| 
 | |
| static void put_pcichild(struct hv_pci_dev *hpdev)
 | |
| {
 | |
| 	if (refcount_dec_and_test(&hpdev->refs))
 | |
| 		kfree(hpdev);
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * There is no good way to get notified from vmbus_onoffer_rescind(),
 | |
|  * so let's use polling here, since this is not a hot path.
 | |
|  */
 | |
| static int wait_for_response(struct hv_device *hdev,
 | |
| 			     struct completion *comp)
 | |
| {
 | |
| 	while (true) {
 | |
| 		if (hdev->channel->rescind) {
 | |
| 			dev_warn_once(&hdev->device, "The device is gone.\n");
 | |
| 			return -ENODEV;
 | |
| 		}
 | |
| 
 | |
| 		if (wait_for_completion_timeout(comp, HZ / 10))
 | |
| 			break;
 | |
| 	}
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * 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.dev = PCI_SLOT(devfn);
 | |
| 	wslot.bits.func = PCI_FUNC(devfn);
 | |
| 
 | |
| 	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(slot_no.bits.dev, slot_no.bits.func);
 | |
| }
 | |
| 
 | |
| static void hv_pci_read_mmio(struct device *dev, phys_addr_t gpa, int size, u32 *val)
 | |
| {
 | |
| 	struct hv_mmio_read_input *in;
 | |
| 	struct hv_mmio_read_output *out;
 | |
| 	u64 ret;
 | |
| 
 | |
| 	/*
 | |
| 	 * Must be called with interrupts disabled so it is safe
 | |
| 	 * to use the per-cpu input argument page.  Use it for
 | |
| 	 * both input and output.
 | |
| 	 */
 | |
| 	in = *this_cpu_ptr(hyperv_pcpu_input_arg);
 | |
| 	out = *this_cpu_ptr(hyperv_pcpu_input_arg) + sizeof(*in);
 | |
| 	in->gpa = gpa;
 | |
| 	in->size = size;
 | |
| 
 | |
| 	ret = hv_do_hypercall(HVCALL_MMIO_READ, in, out);
 | |
| 	if (hv_result_success(ret)) {
 | |
| 		switch (size) {
 | |
| 		case 1:
 | |
| 			*val = *(u8 *)(out->data);
 | |
| 			break;
 | |
| 		case 2:
 | |
| 			*val = *(u16 *)(out->data);
 | |
| 			break;
 | |
| 		default:
 | |
| 			*val = *(u32 *)(out->data);
 | |
| 			break;
 | |
| 		}
 | |
| 	} else
 | |
| 		dev_err(dev, "MMIO read hypercall error %llx addr %llx size %d\n",
 | |
| 				ret, gpa, size);
 | |
| }
 | |
| 
 | |
| static void hv_pci_write_mmio(struct device *dev, phys_addr_t gpa, int size, u32 val)
 | |
| {
 | |
| 	struct hv_mmio_write_input *in;
 | |
| 	u64 ret;
 | |
| 
 | |
| 	/*
 | |
| 	 * Must be called with interrupts disabled so it is safe
 | |
| 	 * to use the per-cpu input argument memory.
 | |
| 	 */
 | |
| 	in = *this_cpu_ptr(hyperv_pcpu_input_arg);
 | |
| 	in->gpa = gpa;
 | |
| 	in->size = size;
 | |
| 	switch (size) {
 | |
| 	case 1:
 | |
| 		*(u8 *)(in->data) = val;
 | |
| 		break;
 | |
| 	case 2:
 | |
| 		*(u16 *)(in->data) = val;
 | |
| 		break;
 | |
| 	default:
 | |
| 		*(u32 *)(in->data) = val;
 | |
| 		break;
 | |
| 	}
 | |
| 
 | |
| 	ret = hv_do_hypercall(HVCALL_MMIO_WRITE, in, NULL);
 | |
| 	if (!hv_result_success(ret))
 | |
| 		dev_err(dev, "MMIO write hypercall error %llx addr %llx size %d\n",
 | |
| 				ret, gpa, size);
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * PCI Configuration Space for these root PCI buses is implemented as a pair
 | |
|  * of pages in memory-mapped I/O space.  Writing to the first page chooses
 | |
|  * the PCI function being written or read.  Once the first page has been
 | |
|  * written to, the following page maps in the entire configuration space of
 | |
|  * the function.
 | |
|  */
 | |
| 
 | |
| /**
 | |
|  * _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)
 | |
| {
 | |
| 	struct hv_pcibus_device *hbus = hpdev->hbus;
 | |
| 	struct device *dev = &hbus->hdev->device;
 | |
| 	int offset = where + CFG_PAGE_OFFSET;
 | |
| 	unsigned long flags;
 | |
| 
 | |
| 	/*
 | |
| 	 * 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) ||
 | |
| 		   (where >= PCI_INTERRUPT_PIN && where + size <= PCI_MIN_GNT)) {
 | |
| 		/*
 | |
| 		 * Interrupt Line and Interrupt PIN are hard-wired to zero
 | |
| 		 * because this front-end only supports message-signaled
 | |
| 		 * interrupts.
 | |
| 		 */
 | |
| 		*val = 0;
 | |
| 	} else if (where + size <= CFG_PAGE_SIZE) {
 | |
| 
 | |
| 		spin_lock_irqsave(&hbus->config_lock, flags);
 | |
| 		if (hbus->use_calls) {
 | |
| 			phys_addr_t addr = hbus->mem_config->start + offset;
 | |
| 
 | |
| 			hv_pci_write_mmio(dev, hbus->mem_config->start, 4,
 | |
| 						hpdev->desc.win_slot.slot);
 | |
| 			hv_pci_read_mmio(dev, addr, size, val);
 | |
| 		} else {
 | |
| 			void __iomem *addr = hbus->cfg_addr + offset;
 | |
| 
 | |
| 			/* Choose the function to be read. (See comment above) */
 | |
| 			writel(hpdev->desc.win_slot.slot, hbus->cfg_addr);
 | |
| 			/* Make sure the function was chosen before reading. */
 | |
| 			mb();
 | |
| 			/* Read from that function's config space. */
 | |
| 			switch (size) {
 | |
| 			case 1:
 | |
| 				*val = readb(addr);
 | |
| 				break;
 | |
| 			case 2:
 | |
| 				*val = readw(addr);
 | |
| 				break;
 | |
| 			default:
 | |
| 				*val = readl(addr);
 | |
| 				break;
 | |
| 			}
 | |
| 			/*
 | |
| 			 * Make sure the read was done before we release the
 | |
| 			 * spinlock allowing consecutive reads/writes.
 | |
| 			 */
 | |
| 			mb();
 | |
| 		}
 | |
| 		spin_unlock_irqrestore(&hbus->config_lock, flags);
 | |
| 	} else {
 | |
| 		dev_err(dev, "Attempt to read beyond a function's config space.\n");
 | |
| 	}
 | |
| }
 | |
| 
 | |
| static u16 hv_pcifront_get_vendor_id(struct hv_pci_dev *hpdev)
 | |
| {
 | |
| 	struct hv_pcibus_device *hbus = hpdev->hbus;
 | |
| 	struct device *dev = &hbus->hdev->device;
 | |
| 	u32 val;
 | |
| 	u16 ret;
 | |
| 	unsigned long flags;
 | |
| 
 | |
| 	spin_lock_irqsave(&hbus->config_lock, flags);
 | |
| 
 | |
| 	if (hbus->use_calls) {
 | |
| 		phys_addr_t addr = hbus->mem_config->start +
 | |
| 					 CFG_PAGE_OFFSET + PCI_VENDOR_ID;
 | |
| 
 | |
| 		hv_pci_write_mmio(dev, hbus->mem_config->start, 4,
 | |
| 					hpdev->desc.win_slot.slot);
 | |
| 		hv_pci_read_mmio(dev, addr, 2, &val);
 | |
| 		ret = val;  /* Truncates to 16 bits */
 | |
| 	} else {
 | |
| 		void __iomem *addr = hbus->cfg_addr + CFG_PAGE_OFFSET +
 | |
| 					     PCI_VENDOR_ID;
 | |
| 		/* Choose the function to be read. (See comment above) */
 | |
| 		writel(hpdev->desc.win_slot.slot, hbus->cfg_addr);
 | |
| 		/* Make sure the function was chosen before we start reading. */
 | |
| 		mb();
 | |
| 		/* Read from that function's config space. */
 | |
| 		ret = readw(addr);
 | |
| 		/*
 | |
| 		 * mb() is not required here, because the
 | |
| 		 * spin_unlock_irqrestore() is a barrier.
 | |
| 		 */
 | |
| 	}
 | |
| 
 | |
| 	spin_unlock_irqrestore(&hbus->config_lock, flags);
 | |
| 
 | |
| 	return ret;
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * _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)
 | |
| {
 | |
| 	struct hv_pcibus_device *hbus = hpdev->hbus;
 | |
| 	struct device *dev = &hbus->hdev->device;
 | |
| 	int offset = where + CFG_PAGE_OFFSET;
 | |
| 	unsigned long flags;
 | |
| 
 | |
| 	if (where >= PCI_SUBSYSTEM_VENDOR_ID &&
 | |
| 	    where + size <= PCI_CAPABILITY_LIST) {
 | |
| 		/* SSIDs and ROM BARs are read-only */
 | |
| 	} else if (where >= PCI_COMMAND && where + size <= CFG_PAGE_SIZE) {
 | |
| 		spin_lock_irqsave(&hbus->config_lock, flags);
 | |
| 
 | |
| 		if (hbus->use_calls) {
 | |
| 			phys_addr_t addr = hbus->mem_config->start + offset;
 | |
| 
 | |
| 			hv_pci_write_mmio(dev, hbus->mem_config->start, 4,
 | |
| 						hpdev->desc.win_slot.slot);
 | |
| 			hv_pci_write_mmio(dev, addr, size, val);
 | |
| 		} else {
 | |
| 			void __iomem *addr = hbus->cfg_addr + offset;
 | |
| 
 | |
| 			/* Choose the function to write. (See comment above) */
 | |
| 			writel(hpdev->desc.win_slot.slot, hbus->cfg_addr);
 | |
| 			/* Make sure the function was chosen before writing. */
 | |
| 			wmb();
 | |
| 			/* Write to that function's config space. */
 | |
| 			switch (size) {
 | |
| 			case 1:
 | |
| 				writeb(val, addr);
 | |
| 				break;
 | |
| 			case 2:
 | |
| 				writew(val, addr);
 | |
| 				break;
 | |
| 			default:
 | |
| 				writel(val, addr);
 | |
| 				break;
 | |
| 			}
 | |
| 			/*
 | |
| 			 * Make sure the write was done before we release the
 | |
| 			 * spinlock allowing consecutive reads/writes.
 | |
| 			 */
 | |
| 			mb();
 | |
| 		}
 | |
| 		spin_unlock_irqrestore(&hbus->config_lock, flags);
 | |
| 	} else {
 | |
| 		dev_err(dev, "Attempt to write beyond a function's config space.\n");
 | |
| 	}
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * 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 = get_pcichild_wslot(hbus, devfn_to_wslot(devfn));
 | |
| 	if (!hpdev)
 | |
| 		return PCIBIOS_DEVICE_NOT_FOUND;
 | |
| 
 | |
| 	_hv_pcifront_read_config(hpdev, where, size, val);
 | |
| 
 | |
| 	put_pcichild(hpdev);
 | |
| 	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 = get_pcichild_wslot(hbus, devfn_to_wslot(devfn));
 | |
| 	if (!hpdev)
 | |
| 		return PCIBIOS_DEVICE_NOT_FOUND;
 | |
| 
 | |
| 	_hv_pcifront_write_config(hpdev, where, size, val);
 | |
| 
 | |
| 	put_pcichild(hpdev);
 | |
| 	return PCIBIOS_SUCCESSFUL;
 | |
| }
 | |
| 
 | |
| /* PCIe operations */
 | |
| static struct pci_ops hv_pcifront_ops = {
 | |
| 	.read  = hv_pcifront_read_config,
 | |
| 	.write = hv_pcifront_write_config,
 | |
| };
 | |
| 
 | |
| /*
 | |
|  * Paravirtual backchannel
 | |
|  *
 | |
|  * Hyper-V 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 comp_pkt;
 | |
| 	void *buf;
 | |
| 	unsigned int len;
 | |
| 	unsigned int bytes_returned;
 | |
| };
 | |
| 
 | |
| /**
 | |
|  * hv_pci_read_config_compl() - Invoked when a response packet
 | |
|  * for a read config block operation arrives.
 | |
|  * @context:		Identifies the read config operation
 | |
|  * @resp:		The response packet itself
 | |
|  * @resp_packet_size:	Size in bytes of the response packet
 | |
|  */
 | |
| static void hv_pci_read_config_compl(void *context, struct pci_response *resp,
 | |
| 				     int resp_packet_size)
 | |
| {
 | |
| 	struct hv_read_config_compl *comp = context;
 | |
| 	struct pci_read_block_response *read_resp =
 | |
| 		(struct pci_read_block_response *)resp;
 | |
| 	unsigned int data_len, hdr_len;
 | |
| 
 | |
| 	hdr_len = offsetof(struct pci_read_block_response, bytes);
 | |
| 	if (resp_packet_size < hdr_len) {
 | |
| 		comp->comp_pkt.completion_status = -1;
 | |
| 		goto out;
 | |
| 	}
 | |
| 
 | |
| 	data_len = resp_packet_size - hdr_len;
 | |
| 	if (data_len > 0 && read_resp->status == 0) {
 | |
| 		comp->bytes_returned = min(comp->len, data_len);
 | |
| 		memcpy(comp->buf, read_resp->bytes, comp->bytes_returned);
 | |
| 	} else {
 | |
| 		comp->bytes_returned = 0;
 | |
| 	}
 | |
| 
 | |
| 	comp->comp_pkt.completion_status = read_resp->status;
 | |
| out:
 | |
| 	complete(&comp->comp_pkt.host_event);
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * hv_read_config_block() - Sends a read config block request to
 | |
|  * the back-end driver running in the Hyper-V parent partition.
 | |
|  * @pdev:		The PCI driver's representation for this device.
 | |
|  * @buf:		Buffer into which the config block will be copied.
 | |
|  * @len:		Size in bytes of buf.
 | |
|  * @block_id:		Identifies the config block which has been requested.
 | |
|  * @bytes_returned:	Size which came back from the back-end driver.
 | |
|  *
 | |
|  * Return: 0 on success, -errno on failure
 | |
|  */
 | |
| static int hv_read_config_block(struct pci_dev *pdev, void *buf,
 | |
| 				unsigned int len, unsigned int block_id,
 | |
| 				unsigned 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)];
 | |
| 	} pkt;
 | |
| 	struct hv_read_config_compl comp_pkt;
 | |
| 	struct pci_read_block *read_blk;
 | |
| 	int ret;
 | |
| 
 | |
| 	if (len == 0 || len > HV_CONFIG_BLOCK_SIZE_MAX)
 | |
| 		return -EINVAL;
 | |
| 
 | |
| 	init_completion(&comp_pkt.comp_pkt.host_event);
 | |
| 	comp_pkt.buf = buf;
 | |
| 	comp_pkt.len = len;
 | |
| 
 | |
| 	memset(&pkt, 0, sizeof(pkt));
 | |
| 	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.type = PCI_READ_BLOCK;
 | |
| 	read_blk->wslot.slot = devfn_to_wslot(pdev->devfn);
 | |
| 	read_blk->block_id = block_id;
 | |
| 	read_blk->bytes_requested = len;
 | |
| 
 | |
| 	ret = vmbus_sendpacket(hbus->hdev->channel, read_blk,
 | |
| 			       sizeof(*read_blk), (unsigned long)&pkt.pkt,
 | |
| 			       VM_PKT_DATA_INBAND,
 | |
| 			       VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 | |
| 	if (ret)
 | |
| 		return ret;
 | |
| 
 | |
| 	ret = wait_for_response(hbus->hdev, &comp_pkt.comp_pkt.host_event);
 | |
| 	if (ret)
 | |
| 		return ret;
 | |
| 
 | |
| 	if (comp_pkt.comp_pkt.completion_status != 0 ||
 | |
| 	    comp_pkt.bytes_returned == 0) {
 | |
| 		dev_err(&hbus->hdev->device,
 | |
| 			"Read Config Block failed: 0x%x, bytes_returned=%d\n",
 | |
| 			comp_pkt.comp_pkt.completion_status,
 | |
| 			comp_pkt.bytes_returned);
 | |
| 		return -EIO;
 | |
| 	}
 | |
| 
 | |
| 	*bytes_returned = comp_pkt.bytes_returned;
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * hv_pci_write_config_compl() - Invoked when a response packet for a write
 | |
|  * config block operation arrives.
 | |
|  * @context:		Identifies the write config operation
 | |
|  * @resp:		The response packet itself
 | |
|  * @resp_packet_size:	Size in bytes of the response packet
 | |
|  */
 | |
| static void hv_pci_write_config_compl(void *context, struct pci_response *resp,
 | |
| 				      int resp_packet_size)
 | |
| {
 | |
| 	struct hv_pci_compl *comp_pkt = context;
 | |
| 
 | |
| 	comp_pkt->completion_status = resp->status;
 | |
| 	complete(&comp_pkt->host_event);
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * hv_write_config_block() - Sends a write config block request to the
 | |
|  * back-end driver running in the Hyper-V parent partition.
 | |
|  * @pdev:		The PCI driver's representation for this device.
 | |
|  * @buf:		Buffer from which the config block will	be copied.
 | |
|  * @len:		Size in bytes of buf.
 | |
|  * @block_id:		Identifies the config block which is being written.
 | |
|  *
 | |
|  * Return: 0 on success, -errno on failure
 | |
|  */
 | |
| static int hv_write_config_block(struct pci_dev *pdev, void *buf,
 | |
| 				unsigned int len, unsigned 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)];
 | |
| 		u32 reserved;
 | |
| 	} pkt;
 | |
| 	struct hv_pci_compl comp_pkt;
 | |
| 	struct pci_write_block *write_blk;
 | |
| 	u32 pkt_size;
 | |
| 	int ret;
 | |
| 
 | |
| 	if (len == 0 || len > HV_CONFIG_BLOCK_SIZE_MAX)
 | |
| 		return -EINVAL;
 | |
| 
 | |
| 	init_completion(&comp_pkt.host_event);
 | |
| 
 | |
| 	memset(&pkt, 0, sizeof(pkt));
 | |
| 	pkt.pkt.completion_func = hv_pci_write_config_compl;
 | |
| 	pkt.pkt.compl_ctxt = &comp_pkt;
 | |
| 	write_blk = (struct pci_write_block *)&pkt.pkt.message;
 | |
| 	write_blk->message_type.type = PCI_WRITE_BLOCK;
 | |
| 	write_blk->wslot.slot = devfn_to_wslot(pdev->devfn);
 | |
| 	write_blk->block_id = block_id;
 | |
| 	write_blk->byte_count = len;
 | |
| 	memcpy(write_blk->bytes, buf, len);
 | |
| 	pkt_size = offsetof(struct pci_write_block, bytes) + len;
 | |
| 	/*
 | |
| 	 * This quirk is required on some hosts shipped around 2018, because
 | |
| 	 * these hosts don't check the pkt_size correctly (new hosts have been
 | |
| 	 * fixed since early 2019). The quirk is also safe on very old hosts
 | |
| 	 * and new hosts, because, on them, what really matters is the length
 | |
| 	 * specified in write_blk->byte_count.
 | |
| 	 */
 | |
| 	pkt_size += sizeof(pkt.reserved);
 | |
| 
 | |
| 	ret = vmbus_sendpacket(hbus->hdev->channel, write_blk, pkt_size,
 | |
| 			       (unsigned long)&pkt.pkt, VM_PKT_DATA_INBAND,
 | |
| 			       VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 | |
| 	if (ret)
 | |
| 		return ret;
 | |
| 
 | |
| 	ret = wait_for_response(hbus->hdev, &comp_pkt.host_event);
 | |
| 	if (ret)
 | |
| 		return ret;
 | |
| 
 | |
| 	if (comp_pkt.completion_status != 0) {
 | |
| 		dev_err(&hbus->hdev->device,
 | |
| 			"Write Config Block failed: 0x%x\n",
 | |
| 			comp_pkt.completion_status);
 | |
| 		return -EIO;
 | |
| 	}
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * hv_register_block_invalidate() - Invoked when a config block invalidation
 | |
|  * arrives from the back-end driver.
 | |
|  * @pdev:		The PCI driver's representation for this device.
 | |
|  * @context:		Identifies the device.
 | |
|  * @block_invalidate:	Identifies all of the blocks being invalidated.
 | |
|  *
 | |
|  * Return: 0 on success, -errno on failure
 | |
|  */
 | |
| static 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 = get_pcichild_wslot(hbus, devfn_to_wslot(pdev->devfn));
 | |
| 	if (!hpdev)
 | |
| 		return -ENODEV;
 | |
| 
 | |
| 	hpdev->block_invalidate = block_invalidate;
 | |
| 	hpdev->invalidate_context = context;
 | |
| 
 | |
| 	put_pcichild(hpdev);
 | |
| 	return 0;
 | |
| 
 | |
| }
 | |
| 
 | |
| /* Interrupt management hooks */
 | |
| static void hv_int_desc_free(struct hv_pci_dev *hpdev,
 | |
| 			     struct tran_int_desc *int_desc)
 | |
| {
 | |
| 	struct pci_delete_interrupt *int_pkt;
 | |
| 	struct {
 | |
| 		struct pci_packet pkt;
 | |
| 		u8 buffer[sizeof(struct pci_delete_interrupt)];
 | |
| 	} ctxt;
 | |
| 
 | |
| 	if (!int_desc->vector_count) {
 | |
| 		kfree(int_desc);
 | |
| 		return;
 | |
| 	}
 | |
| 	memset(&ctxt, 0, sizeof(ctxt));
 | |
| 	int_pkt = (struct pci_delete_interrupt *)&ctxt.pkt.message;
 | |
| 	int_pkt->message_type.type =
 | |
| 		PCI_DELETE_INTERRUPT_MESSAGE;
 | |
| 	int_pkt->wslot.slot = hpdev->desc.win_slot.slot;
 | |
| 	int_pkt->int_desc = *int_desc;
 | |
| 	vmbus_sendpacket(hpdev->hbus->hdev->channel, int_pkt, sizeof(*int_pkt),
 | |
| 			 0, VM_PKT_DATA_INBAND, 0);
 | |
| 	kfree(int_desc);
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * 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 IRT entry and related tracking nonsense.
 | |
|  */
 | |
| static void hv_msi_free(struct irq_domain *domain, struct msi_domain_info *info,
 | |
| 			unsigned int irq)
 | |
| {
 | |
| 	struct hv_pcibus_device *hbus;
 | |
| 	struct hv_pci_dev *hpdev;
 | |
| 	struct pci_dev *pdev;
 | |
| 	struct tran_int_desc *int_desc;
 | |
| 	struct irq_data *irq_data = irq_domain_get_irq_data(domain, irq);
 | |
| 	struct msi_desc *msi = irq_data_get_msi_desc(irq_data);
 | |
| 
 | |
| 	pdev = msi_desc_to_pci_dev(msi);
 | |
| 	hbus = info->data;
 | |
| 	int_desc = irq_data_get_irq_chip_data(irq_data);
 | |
| 	if (!int_desc)
 | |
| 		return;
 | |
| 
 | |
| 	irq_data->chip_data = NULL;
 | |
| 	hpdev = get_pcichild_wslot(hbus, devfn_to_wslot(pdev->devfn));
 | |
| 	if (!hpdev) {
 | |
| 		kfree(int_desc);
 | |
| 		return;
 | |
| 	}
 | |
| 
 | |
| 	hv_int_desc_free(hpdev, int_desc);
 | |
| 	put_pcichild(hpdev);
 | |
| }
 | |
| 
 | |
| static void hv_irq_mask(struct irq_data *data)
 | |
| {
 | |
| 	pci_msi_mask_irq(data);
 | |
| 	if (data->parent_data->chip->irq_mask)
 | |
| 		irq_chip_mask_parent(data);
 | |
| }
 | |
| 
 | |
| static void hv_irq_unmask(struct irq_data *data)
 | |
| {
 | |
| 	hv_arch_irq_unmask(data);
 | |
| 
 | |
| 	if (data->parent_data->chip->irq_unmask)
 | |
| 		irq_chip_unmask_parent(data);
 | |
| 	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;
 | |
| 
 | |
| 	if (resp_packet_size < sizeof(*int_resp)) {
 | |
| 		comp_pkt->comp_pkt.completion_status = -1;
 | |
| 		goto out;
 | |
| 	}
 | |
| 	comp_pkt->comp_pkt.completion_status = resp->status;
 | |
| 	comp_pkt->int_desc = int_resp->int_desc;
 | |
| out:
 | |
| 	complete(&comp_pkt->comp_pkt.host_event);
 | |
| }
 | |
| 
 | |
| static u32 hv_compose_msi_req_v1(
 | |
| 	struct pci_create_interrupt *int_pkt,
 | |
| 	u32 slot, u8 vector, u16 vector_count)
 | |
| {
 | |
| 	int_pkt->message_type.type = PCI_CREATE_INTERRUPT_MESSAGE;
 | |
| 	int_pkt->wslot.slot = slot;
 | |
| 	int_pkt->int_desc.vector = vector;
 | |
| 	int_pkt->int_desc.vector_count = vector_count;
 | |
| 	int_pkt->int_desc.delivery_mode = DELIVERY_MODE;
 | |
| 
 | |
| 	/*
 | |
| 	 * Create MSI w/ dummy vCPU set, overwritten by subsequent retarget in
 | |
| 	 * hv_irq_unmask().
 | |
| 	 */
 | |
| 	int_pkt->int_desc.cpu_mask = CPU_AFFINITY_ALL;
 | |
| 
 | |
| 	return sizeof(*int_pkt);
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * The vCPU selected by hv_compose_multi_msi_req_get_cpu() and
 | |
|  * hv_compose_msi_req_get_cpu() is a "dummy" vCPU because the final vCPU to be
 | |
|  * interrupted is specified later in hv_irq_unmask() and communicated to Hyper-V
 | |
|  * via the HVCALL_RETARGET_INTERRUPT hypercall. But the choice of dummy vCPU is
 | |
|  * not irrelevant because Hyper-V chooses the physical CPU to handle the
 | |
|  * interrupts based on the vCPU specified in message sent to the vPCI VSP in
 | |
|  * hv_compose_msi_msg(). Hyper-V's choice of pCPU is not visible to the guest,
 | |
|  * but assigning too many vPCI device interrupts to the same pCPU can cause a
 | |
|  * performance bottleneck. So we spread out the dummy vCPUs to influence Hyper-V
 | |
|  * to spread out the pCPUs that it selects.
 | |
|  *
 | |
|  * For the single-MSI and MSI-X cases, it's OK for hv_compose_msi_req_get_cpu()
 | |
|  * to always return the same dummy vCPU, because a second call to
 | |
|  * hv_compose_msi_msg() contains the "real" vCPU, causing Hyper-V to choose a
 | |
|  * new pCPU for the interrupt. But for the multi-MSI case, the second call to
 | |
|  * hv_compose_msi_msg() exits without sending a message to the vPCI VSP, so the
 | |
|  * original dummy vCPU is used. This dummy vCPU must be round-robin'ed so that
 | |
|  * the pCPUs are spread out. All interrupts for a multi-MSI device end up using
 | |
|  * the same pCPU, even though the vCPUs will be spread out by later calls
 | |
|  * to hv_irq_unmask(), but that is the best we can do now.
 | |
|  *
 | |
|  * With Hyper-V in Nov 2022, the HVCALL_RETARGET_INTERRUPT hypercall does *not*
 | |
|  * cause Hyper-V to reselect the pCPU based on the specified vCPU. Such an
 | |
|  * enhancement is planned for a future version. With that enhancement, the
 | |
|  * dummy vCPU selection won't matter, and interrupts for the same multi-MSI
 | |
|  * device will be spread across multiple pCPUs.
 | |
|  */
 | |
| 
 | |
| /*
 | |
|  * Create MSI w/ dummy vCPU set targeting just one vCPU, overwritten
 | |
|  * by subsequent retarget in hv_irq_unmask().
 | |
|  */
 | |
| static int hv_compose_msi_req_get_cpu(const struct cpumask *affinity)
 | |
| {
 | |
| 	return cpumask_first_and(affinity, cpu_online_mask);
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Make sure the dummy vCPU values for multi-MSI don't all point to vCPU0.
 | |
|  */
 | |
| static int hv_compose_multi_msi_req_get_cpu(void)
 | |
| {
 | |
| 	static DEFINE_SPINLOCK(multi_msi_cpu_lock);
 | |
| 
 | |
| 	/* -1 means starting with CPU 0 */
 | |
| 	static int cpu_next = -1;
 | |
| 
 | |
| 	unsigned long flags;
 | |
| 	int cpu;
 | |
| 
 | |
| 	spin_lock_irqsave(&multi_msi_cpu_lock, flags);
 | |
| 
 | |
| 	cpu_next = cpumask_next_wrap(cpu_next, cpu_online_mask, nr_cpu_ids,
 | |
| 				     false);
 | |
| 	cpu = cpu_next;
 | |
| 
 | |
| 	spin_unlock_irqrestore(&multi_msi_cpu_lock, flags);
 | |
| 
 | |
| 	return cpu;
 | |
| }
 | |
| 
 | |
| static u32 hv_compose_msi_req_v2(
 | |
| 	struct pci_create_interrupt2 *int_pkt, int cpu,
 | |
| 	u32 slot, u8 vector, u16 vector_count)
 | |
| {
 | |
| 	int_pkt->message_type.type = PCI_CREATE_INTERRUPT_MESSAGE2;
 | |
| 	int_pkt->wslot.slot = slot;
 | |
| 	int_pkt->int_desc.vector = vector;
 | |
| 	int_pkt->int_desc.vector_count = vector_count;
 | |
| 	int_pkt->int_desc.delivery_mode = DELIVERY_MODE;
 | |
| 	int_pkt->int_desc.processor_array[0] =
 | |
| 		hv_cpu_number_to_vp_number(cpu);
 | |
| 	int_pkt->int_desc.processor_count = 1;
 | |
| 
 | |
| 	return sizeof(*int_pkt);
 | |
| }
 | |
| 
 | |
| static u32 hv_compose_msi_req_v3(
 | |
| 	struct pci_create_interrupt3 *int_pkt, int cpu,
 | |
| 	u32 slot, u32 vector, u16 vector_count)
 | |
| {
 | |
| 	int_pkt->message_type.type = PCI_CREATE_INTERRUPT_MESSAGE3;
 | |
| 	int_pkt->wslot.slot = slot;
 | |
| 	int_pkt->int_desc.vector = vector;
 | |
| 	int_pkt->int_desc.reserved = 0;
 | |
| 	int_pkt->int_desc.vector_count = vector_count;
 | |
| 	int_pkt->int_desc.delivery_mode = DELIVERY_MODE;
 | |
| 	int_pkt->int_desc.processor_array[0] =
 | |
| 		hv_cpu_number_to_vp_number(cpu);
 | |
| 	int_pkt->int_desc.processor_count = 1;
 | |
| 
 | |
| 	return sizeof(*int_pkt);
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * 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 hv_pcibus_device *hbus;
 | |
| 	struct vmbus_channel *channel;
 | |
| 	struct hv_pci_dev *hpdev;
 | |
| 	struct pci_bus *pbus;
 | |
| 	struct pci_dev *pdev;
 | |
| 	const struct cpumask *dest;
 | |
| 	struct compose_comp_ctxt comp;
 | |
| 	struct tran_int_desc *int_desc;
 | |
| 	struct msi_desc *msi_desc;
 | |
| 	/*
 | |
| 	 * vector_count should be u16: see hv_msi_desc, hv_msi_desc2
 | |
| 	 * and hv_msi_desc3. vector must be u32: see hv_msi_desc3.
 | |
| 	 */
 | |
| 	u16 vector_count;
 | |
| 	u32 vector;
 | |
| 	struct {
 | |
| 		struct pci_packet pci_pkt;
 | |
| 		union {
 | |
| 			struct pci_create_interrupt v1;
 | |
| 			struct pci_create_interrupt2 v2;
 | |
| 			struct pci_create_interrupt3 v3;
 | |
| 		} int_pkts;
 | |
| 	} __packed ctxt;
 | |
| 	bool multi_msi;
 | |
| 	u64 trans_id;
 | |
| 	u32 size;
 | |
| 	int ret;
 | |
| 	int cpu;
 | |
| 
 | |
| 	msi_desc  = irq_data_get_msi_desc(data);
 | |
| 	multi_msi = !msi_desc->pci.msi_attrib.is_msix &&
 | |
| 		    msi_desc->nvec_used > 1;
 | |
| 
 | |
| 	/* Reuse the previous allocation */
 | |
| 	if (data->chip_data && multi_msi) {
 | |
| 		int_desc = data->chip_data;
 | |
| 		msg->address_hi = int_desc->address >> 32;
 | |
| 		msg->address_lo = int_desc->address & 0xffffffff;
 | |
| 		msg->data = int_desc->data;
 | |
| 		return;
 | |
| 	}
 | |
| 
 | |
| 	pdev = msi_desc_to_pci_dev(msi_desc);
 | |
| 	dest = irq_data_get_effective_affinity_mask(data);
 | |
| 	pbus = pdev->bus;
 | |
| 	hbus = container_of(pbus->sysdata, struct hv_pcibus_device, sysdata);
 | |
| 	channel = hbus->hdev->channel;
 | |
| 	hpdev = get_pcichild_wslot(hbus, devfn_to_wslot(pdev->devfn));
 | |
| 	if (!hpdev)
 | |
| 		goto return_null_message;
 | |
| 
 | |
| 	/* Free any previous message that might have already been composed. */
 | |
| 	if (data->chip_data && !multi_msi) {
 | |
| 		int_desc = data->chip_data;
 | |
| 		data->chip_data = NULL;
 | |
| 		hv_int_desc_free(hpdev, int_desc);
 | |
| 	}
 | |
| 
 | |
| 	int_desc = kzalloc(sizeof(*int_desc), GFP_ATOMIC);
 | |
| 	if (!int_desc)
 | |
| 		goto drop_reference;
 | |
| 
 | |
| 	if (multi_msi) {
 | |
| 		/*
 | |
| 		 * If this is not the first MSI of Multi MSI, we already have
 | |
| 		 * a mapping.  Can exit early.
 | |
| 		 */
 | |
| 		if (msi_desc->irq != data->irq) {
 | |
| 			data->chip_data = int_desc;
 | |
| 			int_desc->address = msi_desc->msg.address_lo |
 | |
| 					    (u64)msi_desc->msg.address_hi << 32;
 | |
| 			int_desc->data = msi_desc->msg.data +
 | |
| 					 (data->irq - msi_desc->irq);
 | |
| 			msg->address_hi = msi_desc->msg.address_hi;
 | |
| 			msg->address_lo = msi_desc->msg.address_lo;
 | |
| 			msg->data = int_desc->data;
 | |
| 			put_pcichild(hpdev);
 | |
| 			return;
 | |
| 		}
 | |
| 		/*
 | |
| 		 * The vector we select here is a dummy value.  The correct
 | |
| 		 * value gets sent to the hypervisor in unmask().  This needs
 | |
| 		 * to be aligned with the count, and also not zero.  Multi-msi
 | |
| 		 * is powers of 2 up to 32, so 32 will always work here.
 | |
| 		 */
 | |
| 		vector = 32;
 | |
| 		vector_count = msi_desc->nvec_used;
 | |
| 		cpu = hv_compose_multi_msi_req_get_cpu();
 | |
| 	} else {
 | |
| 		vector = hv_msi_get_int_vector(data);
 | |
| 		vector_count = 1;
 | |
| 		cpu = hv_compose_msi_req_get_cpu(dest);
 | |
| 	}
 | |
| 
 | |
| 	/*
 | |
| 	 * hv_compose_msi_req_v1 and v2 are for x86 only, meaning 'vector'
 | |
| 	 * can't exceed u8. Cast 'vector' down to u8 for v1/v2 explicitly
 | |
| 	 * for better readability.
 | |
| 	 */
 | |
| 	memset(&ctxt, 0, sizeof(ctxt));
 | |
| 	init_completion(&comp.comp_pkt.host_event);
 | |
| 	ctxt.pci_pkt.completion_func = hv_pci_compose_compl;
 | |
| 	ctxt.pci_pkt.compl_ctxt = ∁
 | |
| 
 | |
| 	switch (hbus->protocol_version) {
 | |
| 	case PCI_PROTOCOL_VERSION_1_1:
 | |
| 		size = hv_compose_msi_req_v1(&ctxt.int_pkts.v1,
 | |
| 					hpdev->desc.win_slot.slot,
 | |
| 					(u8)vector,
 | |
| 					vector_count);
 | |
| 		break;
 | |
| 
 | |
| 	case PCI_PROTOCOL_VERSION_1_2:
 | |
| 	case PCI_PROTOCOL_VERSION_1_3:
 | |
| 		size = hv_compose_msi_req_v2(&ctxt.int_pkts.v2,
 | |
| 					cpu,
 | |
| 					hpdev->desc.win_slot.slot,
 | |
| 					(u8)vector,
 | |
| 					vector_count);
 | |
| 		break;
 | |
| 
 | |
| 	case PCI_PROTOCOL_VERSION_1_4:
 | |
| 		size = hv_compose_msi_req_v3(&ctxt.int_pkts.v3,
 | |
| 					cpu,
 | |
| 					hpdev->desc.win_slot.slot,
 | |
| 					vector,
 | |
| 					vector_count);
 | |
| 		break;
 | |
| 
 | |
| 	default:
 | |
| 		/* As we only negotiate protocol versions known to this driver,
 | |
| 		 * this path should never hit. However, this is it not a hot
 | |
| 		 * path so we print a message to aid future updates.
 | |
| 		 */
 | |
| 		dev_err(&hbus->hdev->device,
 | |
| 			"Unexpected vPCI protocol, update driver.");
 | |
| 		goto free_int_desc;
 | |
| 	}
 | |
| 
 | |
| 	ret = vmbus_sendpacket_getid(hpdev->hbus->hdev->channel, &ctxt.int_pkts,
 | |
| 				     size, (unsigned long)&ctxt.pci_pkt,
 | |
| 				     &trans_id, VM_PKT_DATA_INBAND,
 | |
| 				     VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 | |
| 	if (ret) {
 | |
| 		dev_err(&hbus->hdev->device,
 | |
| 			"Sending request for interrupt failed: 0x%x",
 | |
| 			comp.comp_pkt.completion_status);
 | |
| 		goto free_int_desc;
 | |
| 	}
 | |
| 
 | |
| 	/*
 | |
| 	 * Prevents hv_pci_onchannelcallback() from running concurrently
 | |
| 	 * in the tasklet.
 | |
| 	 */
 | |
| 	tasklet_disable_in_atomic(&channel->callback_event);
 | |
| 
 | |
| 	/*
 | |
| 	 * Since this function is called with IRQ locks held, can't
 | |
| 	 * do normal wait for completion; instead poll.
 | |
| 	 */
 | |
| 	while (!try_wait_for_completion(&comp.comp_pkt.host_event)) {
 | |
| 		unsigned long flags;
 | |
| 
 | |
| 		/* 0xFFFF means an invalid PCI VENDOR ID. */
 | |
| 		if (hv_pcifront_get_vendor_id(hpdev) == 0xFFFF) {
 | |
| 			dev_err_once(&hbus->hdev->device,
 | |
| 				     "the device has gone\n");
 | |
| 			goto enable_tasklet;
 | |
| 		}
 | |
| 
 | |
| 		/*
 | |
| 		 * Make sure that the ring buffer data structure doesn't get
 | |
| 		 * freed while we dereference the ring buffer pointer.  Test
 | |
| 		 * for the channel's onchannel_callback being NULL within a
 | |
| 		 * sched_lock critical section.  See also the inline comments
 | |
| 		 * in vmbus_reset_channel_cb().
 | |
| 		 */
 | |
| 		spin_lock_irqsave(&channel->sched_lock, flags);
 | |
| 		if (unlikely(channel->onchannel_callback == NULL)) {
 | |
| 			spin_unlock_irqrestore(&channel->sched_lock, flags);
 | |
| 			goto enable_tasklet;
 | |
| 		}
 | |
| 		hv_pci_onchannelcallback(hbus);
 | |
| 		spin_unlock_irqrestore(&channel->sched_lock, flags);
 | |
| 
 | |
| 		udelay(100);
 | |
| 	}
 | |
| 
 | |
| 	tasklet_enable(&channel->callback_event);
 | |
| 
 | |
| 	if (comp.comp_pkt.completion_status < 0) {
 | |
| 		dev_err(&hbus->hdev->device,
 | |
| 			"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;
 | |
| 
 | |
| 	put_pcichild(hpdev);
 | |
| 	return;
 | |
| 
 | |
| enable_tasklet:
 | |
| 	tasklet_enable(&channel->callback_event);
 | |
| 	/*
 | |
| 	 * The completion packet on the stack becomes invalid after 'return';
 | |
| 	 * remove the ID from the VMbus requestor if the identifier is still
 | |
| 	 * mapped to/associated with the packet.  (The identifier could have
 | |
| 	 * been 're-used', i.e., already removed and (re-)mapped.)
 | |
| 	 *
 | |
| 	 * Cf. hv_pci_onchannelcallback().
 | |
| 	 */
 | |
| 	vmbus_request_addr_match(channel, trans_id, (unsigned long)&ctxt.pci_pkt);
 | |
| free_int_desc:
 | |
| 	kfree(int_desc);
 | |
| drop_reference:
 | |
| 	put_pcichild(hpdev);
 | |
| 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	= irq_chip_set_affinity_parent,
 | |
| #ifdef CONFIG_X86
 | |
| 	.irq_ack		= irq_chip_ack_parent,
 | |
| #elif defined(CONFIG_ARM64)
 | |
| 	.irq_eoi		= irq_chip_eoi_parent,
 | |
| #endif
 | |
| 	.irq_mask		= hv_irq_mask,
 | |
| 	.irq_unmask		= hv_irq_unmask,
 | |
| };
 | |
| 
 | |
| static struct msi_domain_ops hv_msi_ops = {
 | |
| 	.msi_prepare	= hv_msi_prepare,
 | |
| 	.msi_free	= hv_msi_free,
 | |
| };
 | |
| 
 | |
| /**
 | |
|  * 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.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 = FLOW_HANDLER;
 | |
| 	hbus->msi_info.handler_name = FLOW_NAME;
 | |
| 	hbus->msi_info.data = hbus;
 | |
| 	hbus->irq_domain = pci_msi_create_irq_domain(hbus->fwnode,
 | |
| 						     &hbus->msi_info,
 | |
| 						     hv_pci_get_root_domain());
 | |
| 	if (!hbus->irq_domain) {
 | |
| 		dev_err(&hbus->hdev->device,
 | |
| 			"Failed to build an MSI IRQ domain\n");
 | |
| 		return -ENODEV;
 | |
| 	}
 | |
| 
 | |
| 	dev_set_msi_domain(&hbus->bridge->dev, hbus->irq_domain);
 | |
| 
 | |
| 	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 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_entry(hpdev, &hbus->children, list_entry) {
 | |
| 		for (i = 0; i < PCI_STD_NUM_BARS; i++) {
 | |
| 			if (hpdev->probed_bar[i] & PCI_BASE_ADDRESS_SPACE_IO)
 | |
| 				dev_err(&hbus->hdev->device,
 | |
| 					"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;
 | |
| 	unsigned long flags;
 | |
| 	u64 bar_val;
 | |
| 	u32 command;
 | |
| 	bool high;
 | |
| 	int i;
 | |
| 
 | |
| 	if (hbus->low_mmio_space) {
 | |
| 		low_size = 1ULL << (63 - __builtin_clzll(hbus->low_mmio_space));
 | |
| 		low_base = hbus->low_mmio_res->start;
 | |
| 	}
 | |
| 
 | |
| 	if (hbus->high_mmio_space) {
 | |
| 		high_size = 1ULL <<
 | |
| 			(63 - __builtin_clzll(hbus->high_mmio_space));
 | |
| 		high_base = hbus->high_mmio_res->start;
 | |
| 	}
 | |
| 
 | |
| 	spin_lock_irqsave(&hbus->device_list_lock, flags);
 | |
| 
 | |
| 	/*
 | |
| 	 * Clear the memory enable bit, in case it's already set. This occurs
 | |
| 	 * in the suspend path of hibernation, where the device is suspended,
 | |
| 	 * resumed and suspended again: see hibernation_snapshot() and
 | |
| 	 * hibernation_platform_enter().
 | |
| 	 *
 | |
| 	 * If the memory enable bit is already set, Hyper-V silently ignores
 | |
| 	 * the below BAR updates, and the related PCI device driver can not
 | |
| 	 * work, because reading from the device register(s) always returns
 | |
| 	 * 0xFFFFFFFF (PCI_ERROR_RESPONSE).
 | |
| 	 */
 | |
| 	list_for_each_entry(hpdev, &hbus->children, list_entry) {
 | |
| 		_hv_pcifront_read_config(hpdev, PCI_COMMAND, 2, &command);
 | |
| 		command &= ~PCI_COMMAND_MEMORY;
 | |
| 		_hv_pcifront_write_config(hpdev, PCI_COMMAND, 2, command);
 | |
| 	}
 | |
| 
 | |
| 	/* Pick addresses for the BARs. */
 | |
| 	do {
 | |
| 		list_for_each_entry(hpdev, &hbus->children, list_entry) {
 | |
| 			for (i = 0; i < PCI_STD_NUM_BARS; 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));
 | |
| 					i++;
 | |
| 					_hv_pcifront_write_config(hpdev,
 | |
| 						PCI_BASE_ADDRESS_0 + (4 * i),
 | |
| 						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) {
 | |
| 				/*
 | |
| 				 * No need to set the PCI_COMMAND_MEMORY bit as
 | |
| 				 * the core PCI driver doesn't require the bit
 | |
| 				 * to be pre-set. Actually here we intentionally
 | |
| 				 * keep the bit off so that the PCI BAR probing
 | |
| 				 * in the core PCI driver doesn't cause Hyper-V
 | |
| 				 * to unnecessarily unmap/map the virtual BARs
 | |
| 				 * from/to the physical BARs multiple times.
 | |
| 				 * This reduces the VM boot time significantly
 | |
| 				 * if the BAR sizes are huge.
 | |
| 				 */
 | |
| 				break;
 | |
| 			}
 | |
| 		}
 | |
| 
 | |
| 		high_size >>= 1;
 | |
| 		low_size >>= 1;
 | |
| 	}  while (high_size || low_size);
 | |
| 
 | |
| 	spin_unlock_irqrestore(&hbus->device_list_lock, flags);
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Assign entries in sysfs pci slot directory.
 | |
|  *
 | |
|  * Note that this function does not need to lock the children list
 | |
|  * because it is called from pci_devices_present_work which
 | |
|  * is serialized with hv_eject_device_work because they are on the
 | |
|  * same ordered workqueue. Therefore hbus->children list will not change
 | |
|  * even when pci_create_slot sleeps.
 | |
|  */
 | |
| static void hv_pci_assign_slots(struct hv_pcibus_device *hbus)
 | |
| {
 | |
| 	struct hv_pci_dev *hpdev;
 | |
| 	char name[SLOT_NAME_SIZE];
 | |
| 	int slot_nr;
 | |
| 
 | |
| 	list_for_each_entry(hpdev, &hbus->children, list_entry) {
 | |
| 		if (hpdev->pci_slot)
 | |
| 			continue;
 | |
| 
 | |
| 		slot_nr = PCI_SLOT(wslot_to_devfn(hpdev->desc.win_slot.slot));
 | |
| 		snprintf(name, SLOT_NAME_SIZE, "%u", hpdev->desc.ser);
 | |
| 		hpdev->pci_slot = pci_create_slot(hbus->bridge->bus, slot_nr,
 | |
| 					  name, NULL);
 | |
| 		if (IS_ERR(hpdev->pci_slot)) {
 | |
| 			pr_warn("pci_create slot %s failed\n", name);
 | |
| 			hpdev->pci_slot = NULL;
 | |
| 		}
 | |
| 	}
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Remove entries in sysfs pci slot directory.
 | |
|  */
 | |
| static void hv_pci_remove_slots(struct hv_pcibus_device *hbus)
 | |
| {
 | |
| 	struct hv_pci_dev *hpdev;
 | |
| 
 | |
| 	list_for_each_entry(hpdev, &hbus->children, list_entry) {
 | |
| 		if (!hpdev->pci_slot)
 | |
| 			continue;
 | |
| 		pci_destroy_slot(hpdev->pci_slot);
 | |
| 		hpdev->pci_slot = NULL;
 | |
| 	}
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Set NUMA node for the devices on the bus
 | |
|  */
 | |
| static void hv_pci_assign_numa_node(struct hv_pcibus_device *hbus)
 | |
| {
 | |
| 	struct pci_dev *dev;
 | |
| 	struct pci_bus *bus = hbus->bridge->bus;
 | |
| 	struct hv_pci_dev *hv_dev;
 | |
| 
 | |
| 	list_for_each_entry(dev, &bus->devices, bus_list) {
 | |
| 		hv_dev = get_pcichild_wslot(hbus, devfn_to_wslot(dev->devfn));
 | |
| 		if (!hv_dev)
 | |
| 			continue;
 | |
| 
 | |
| 		if (hv_dev->desc.flags & HV_PCI_DEVICE_FLAG_NUMA_AFFINITY &&
 | |
| 		    hv_dev->desc.virtual_numa_node < num_possible_nodes())
 | |
| 			/*
 | |
| 			 * The kernel may boot with some NUMA nodes offline
 | |
| 			 * (e.g. in a KDUMP kernel) or with NUMA disabled via
 | |
| 			 * "numa=off". In those cases, adjust the host provided
 | |
| 			 * NUMA node to a valid NUMA node used by the kernel.
 | |
| 			 */
 | |
| 			set_dev_node(&dev->dev,
 | |
| 				     numa_map_to_online_node(
 | |
| 					     hv_dev->desc.virtual_numa_node));
 | |
| 
 | |
| 		put_pcichild(hv_dev);
 | |
| 	}
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * 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)
 | |
| {
 | |
| 	int error;
 | |
| 	struct pci_host_bridge *bridge = hbus->bridge;
 | |
| 
 | |
| 	bridge->dev.parent = &hbus->hdev->device;
 | |
| 	bridge->sysdata = &hbus->sysdata;
 | |
| 	bridge->ops = &hv_pcifront_ops;
 | |
| 
 | |
| 	error = pci_scan_root_bus_bridge(bridge);
 | |
| 	if (error)
 | |
| 		return error;
 | |
| 
 | |
| 	pci_lock_rescan_remove();
 | |
| 	hv_pci_assign_numa_node(hbus);
 | |
| 	pci_bus_assign_resources(bridge->bus);
 | |
| 	hv_pci_assign_slots(hbus);
 | |
| 	pci_bus_add_devices(bridge->bus);
 | |
| 	pci_unlock_rescan_remove();
 | |
| 	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 response 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;
 | |
| 	s32 status;
 | |
| 	int i;
 | |
| 
 | |
| 	status = (resp_packet_size < sizeof(*q_res_req)) ? -1 : resp->status;
 | |
| 	if (status < 0) {
 | |
| 		dev_err(&completion->hpdev->hbus->hdev->device,
 | |
| 			"query resource requirements failed: %x\n",
 | |
| 			status);
 | |
| 	} else {
 | |
| 		for (i = 0; i < PCI_STD_NUM_BARS; i++) {
 | |
| 			completion->hpdev->probed_bar[i] =
 | |
| 				q_res_req->probed_bar[i];
 | |
| 		}
 | |
| 	}
 | |
| 
 | |
| 	complete(&completion->host_event);
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * 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 hv_pcidev_description *desc)
 | |
| {
 | |
| 	struct hv_pci_dev *hpdev;
 | |
| 	struct pci_child_message *res_req;
 | |
| 	struct q_res_req_compl comp_pkt;
 | |
| 	struct {
 | |
| 		struct pci_packet init_packet;
 | |
| 		u8 buffer[sizeof(struct pci_child_message)];
 | |
| 	} pkt;
 | |
| 	unsigned long flags;
 | |
| 	int ret;
 | |
| 
 | |
| 	hpdev = kzalloc(sizeof(*hpdev), GFP_KERNEL);
 | |
| 	if (!hpdev)
 | |
| 		return NULL;
 | |
| 
 | |
| 	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.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;
 | |
| 
 | |
| 	if (wait_for_response(hbus->hdev, &comp_pkt.host_event))
 | |
| 		goto error;
 | |
| 
 | |
| 	hpdev->desc = *desc;
 | |
| 	refcount_set(&hpdev->refs, 1);
 | |
| 	get_pcichild(hpdev);
 | |
| 	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;
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * get_pcichild_wslot() - 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 the internal
 | |
|  * representation of it.  It acquires a reference on it, so that
 | |
|  * the device won't be deleted while somebody is using it.  The
 | |
|  * caller is responsible for calling put_pcichild() to release
 | |
|  * this reference.
 | |
|  *
 | |
|  * Return:	Internal representation of a PCI device
 | |
|  */
 | |
| static struct hv_pci_dev *get_pcichild_wslot(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;
 | |
| 			get_pcichild(hpdev);
 | |
| 			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 serialized with hv_eject_device_work(),
 | |
|  * because both are pushed to the ordered workqueue hbus->wq.
 | |
|  */
 | |
| static void pci_devices_present_work(struct work_struct *work)
 | |
| {
 | |
| 	u32 child_no;
 | |
| 	bool found;
 | |
| 	struct hv_pcidev_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);
 | |
| 
 | |
| 	/* 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)
 | |
| 		return;
 | |
| 
 | |
| 	mutex_lock(&hbus->state_lock);
 | |
| 
 | |
| 	/* First, mark all existing children as reported missing. */
 | |
| 	spin_lock_irqsave(&hbus->device_list_lock, flags);
 | |
| 	list_for_each_entry(hpdev, &hbus->children, 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_entry(hpdev, &hbus->children, 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)
 | |
| 				dev_err(&hbus->hdev->device,
 | |
| 					"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_entry(hpdev, &hbus->children, list_entry) {
 | |
| 			if (hpdev->reported_missing) {
 | |
| 				found = true;
 | |
| 				put_pcichild(hpdev);
 | |
| 				list_move_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);
 | |
| 
 | |
| 		if (hpdev->pci_slot)
 | |
| 			pci_destroy_slot(hpdev->pci_slot);
 | |
| 
 | |
| 		put_pcichild(hpdev);
 | |
| 	}
 | |
| 
 | |
| 	switch (hbus->state) {
 | |
| 	case hv_pcibus_installed:
 | |
| 		/*
 | |
| 		 * Tell the core to rescan bus
 | |
| 		 * because there may have been changes.
 | |
| 		 */
 | |
| 		pci_lock_rescan_remove();
 | |
| 		pci_scan_child_bus(hbus->bridge->bus);
 | |
| 		hv_pci_assign_numa_node(hbus);
 | |
| 		hv_pci_assign_slots(hbus);
 | |
| 		pci_unlock_rescan_remove();
 | |
| 		break;
 | |
| 
 | |
| 	case hv_pcibus_init:
 | |
| 	case hv_pcibus_probed:
 | |
| 		survey_child_resources(hbus);
 | |
| 		break;
 | |
| 
 | |
| 	default:
 | |
| 		break;
 | |
| 	}
 | |
| 
 | |
| 	mutex_unlock(&hbus->state_lock);
 | |
| 
 | |
| 	kfree(dr);
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * hv_pci_start_relations_work() - Queue work to start device discovery
 | |
|  * @hbus:	Root PCI bus, as understood by this driver
 | |
|  * @dr:		The list of children returned from host
 | |
|  *
 | |
|  * Return:  0 on success, -errno on failure
 | |
|  */
 | |
| static int hv_pci_start_relations_work(struct hv_pcibus_device *hbus,
 | |
| 				       struct hv_dr_state *dr)
 | |
| {
 | |
| 	struct hv_dr_work *dr_wrk;
 | |
| 	unsigned long flags;
 | |
| 	bool pending_dr;
 | |
| 
 | |
| 	if (hbus->state == hv_pcibus_removing) {
 | |
| 		dev_info(&hbus->hdev->device,
 | |
| 			 "PCI VMBus BUS_RELATIONS: ignored\n");
 | |
| 		return -ENOENT;
 | |
| 	}
 | |
| 
 | |
| 	dr_wrk = kzalloc(sizeof(*dr_wrk), GFP_NOWAIT);
 | |
| 	if (!dr_wrk)
 | |
| 		return -ENOMEM;
 | |
| 
 | |
| 	INIT_WORK(&dr_wrk->wrk, pci_devices_present_work);
 | |
| 	dr_wrk->bus = hbus;
 | |
| 
 | |
| 	spin_lock_irqsave(&hbus->device_list_lock, flags);
 | |
| 	/*
 | |
| 	 * If pending_dr is true, we have already queued a work,
 | |
| 	 * which will see the new dr. Otherwise, we need to
 | |
| 	 * queue a new work.
 | |
| 	 */
 | |
| 	pending_dr = !list_empty(&hbus->dr_list);
 | |
| 	list_add_tail(&dr->list_entry, &hbus->dr_list);
 | |
| 	spin_unlock_irqrestore(&hbus->device_list_lock, flags);
 | |
| 
 | |
| 	if (pending_dr)
 | |
| 		kfree(dr_wrk);
 | |
| 	else
 | |
| 		queue_work(hbus->wq, &dr_wrk->wrk);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * hv_pci_devices_present() - Handle list of new children
 | |
|  * @hbus:      Root PCI bus, as understood by this driver
 | |
|  * @relations: Packet from host listing children
 | |
|  *
 | |
|  * Process a new list of devices on the bus. The list of devices is
 | |
|  * discovered by VSP and sent to us via VSP message PCI_BUS_RELATIONS,
 | |
|  * 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;
 | |
| 	int i;
 | |
| 
 | |
| 	dr = kzalloc(struct_size(dr, func, relations->device_count),
 | |
| 		     GFP_NOWAIT);
 | |
| 	if (!dr)
 | |
| 		return;
 | |
| 
 | |
| 	dr->device_count = relations->device_count;
 | |
| 	for (i = 0; i < dr->device_count; i++) {
 | |
| 		dr->func[i].v_id = relations->func[i].v_id;
 | |
| 		dr->func[i].d_id = relations->func[i].d_id;
 | |
| 		dr->func[i].rev = relations->func[i].rev;
 | |
| 		dr->func[i].prog_intf = relations->func[i].prog_intf;
 | |
| 		dr->func[i].subclass = relations->func[i].subclass;
 | |
| 		dr->func[i].base_class = relations->func[i].base_class;
 | |
| 		dr->func[i].subsystem_id = relations->func[i].subsystem_id;
 | |
| 		dr->func[i].win_slot = relations->func[i].win_slot;
 | |
| 		dr->func[i].ser = relations->func[i].ser;
 | |
| 	}
 | |
| 
 | |
| 	if (hv_pci_start_relations_work(hbus, dr))
 | |
| 		kfree(dr);
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * hv_pci_devices_present2() - Handle list of new children
 | |
|  * @hbus:	Root PCI bus, as understood by this driver
 | |
|  * @relations:	Packet from host listing children
 | |
|  *
 | |
|  * This function is the v2 version of hv_pci_devices_present()
 | |
|  */
 | |
| static void hv_pci_devices_present2(struct hv_pcibus_device *hbus,
 | |
| 				    struct pci_bus_relations2 *relations)
 | |
| {
 | |
| 	struct hv_dr_state *dr;
 | |
| 	int i;
 | |
| 
 | |
| 	dr = kzalloc(struct_size(dr, func, relations->device_count),
 | |
| 		     GFP_NOWAIT);
 | |
| 	if (!dr)
 | |
| 		return;
 | |
| 
 | |
| 	dr->device_count = relations->device_count;
 | |
| 	for (i = 0; i < dr->device_count; i++) {
 | |
| 		dr->func[i].v_id = relations->func[i].v_id;
 | |
| 		dr->func[i].d_id = relations->func[i].d_id;
 | |
| 		dr->func[i].rev = relations->func[i].rev;
 | |
| 		dr->func[i].prog_intf = relations->func[i].prog_intf;
 | |
| 		dr->func[i].subclass = relations->func[i].subclass;
 | |
| 		dr->func[i].base_class = relations->func[i].base_class;
 | |
| 		dr->func[i].subsystem_id = relations->func[i].subsystem_id;
 | |
| 		dr->func[i].win_slot = relations->func[i].win_slot;
 | |
| 		dr->func[i].ser = relations->func[i].ser;
 | |
| 		dr->func[i].flags = relations->func[i].flags;
 | |
| 		dr->func[i].virtual_numa_node =
 | |
| 			relations->func[i].virtual_numa_node;
 | |
| 	}
 | |
| 
 | |
| 	if (hv_pci_start_relations_work(hbus, dr))
 | |
| 		kfree(dr);
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * 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_pcibus_device *hbus;
 | |
| 	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)];
 | |
| 	} ctxt;
 | |
| 
 | |
| 	hpdev = container_of(work, struct hv_pci_dev, wrk);
 | |
| 	hbus = hpdev->hbus;
 | |
| 
 | |
| 	mutex_lock(&hbus->state_lock);
 | |
| 
 | |
| 	/*
 | |
| 	 * Ejection can come before or after the PCI bus has been set up, so
 | |
| 	 * attempt to find it and tear down the bus state, if it exists.  This
 | |
| 	 * must be done without constructs like pci_domain_nr(hbus->bridge->bus)
 | |
| 	 * because hbus->bridge->bus may not exist yet.
 | |
| 	 */
 | |
| 	wslot = wslot_to_devfn(hpdev->desc.win_slot.slot);
 | |
| 	pdev = pci_get_domain_bus_and_slot(hbus->bridge->domain_nr, 0, wslot);
 | |
| 	if (pdev) {
 | |
| 		pci_lock_rescan_remove();
 | |
| 		pci_stop_and_remove_bus_device(pdev);
 | |
| 		pci_dev_put(pdev);
 | |
| 		pci_unlock_rescan_remove();
 | |
| 	}
 | |
| 
 | |
| 	spin_lock_irqsave(&hbus->device_list_lock, flags);
 | |
| 	list_del(&hpdev->list_entry);
 | |
| 	spin_unlock_irqrestore(&hbus->device_list_lock, flags);
 | |
| 
 | |
| 	if (hpdev->pci_slot)
 | |
| 		pci_destroy_slot(hpdev->pci_slot);
 | |
| 
 | |
| 	memset(&ctxt, 0, sizeof(ctxt));
 | |
| 	ejct_pkt = (struct pci_eject_response *)&ctxt.pkt.message;
 | |
| 	ejct_pkt->message_type.type = PCI_EJECTION_COMPLETE;
 | |
| 	ejct_pkt->wslot.slot = hpdev->desc.win_slot.slot;
 | |
| 	vmbus_sendpacket(hbus->hdev->channel, ejct_pkt,
 | |
| 			 sizeof(*ejct_pkt), 0,
 | |
| 			 VM_PKT_DATA_INBAND, 0);
 | |
| 
 | |
| 	/* For the get_pcichild() in hv_pci_eject_device() */
 | |
| 	put_pcichild(hpdev);
 | |
| 	/* For the two refs got in new_pcichild_device() */
 | |
| 	put_pcichild(hpdev);
 | |
| 	put_pcichild(hpdev);
 | |
| 	/* hpdev has been freed. Do not use it any more. */
 | |
| 
 | |
| 	mutex_unlock(&hbus->state_lock);
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * 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)
 | |
| {
 | |
| 	struct hv_pcibus_device *hbus = hpdev->hbus;
 | |
| 	struct hv_device *hdev = hbus->hdev;
 | |
| 
 | |
| 	if (hbus->state == hv_pcibus_removing) {
 | |
| 		dev_info(&hdev->device, "PCI VMBus EJECT: ignored\n");
 | |
| 		return;
 | |
| 	}
 | |
| 
 | |
| 	get_pcichild(hpdev);
 | |
| 	INIT_WORK(&hpdev->wrk, hv_eject_device_work);
 | |
| 	queue_work(hbus->wq, &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;
 | |
| 	struct vmbus_channel *chan = hbus->hdev->channel;
 | |
| 	u32 bytes_recvd;
 | |
| 	u64 req_id, req_addr;
 | |
| 	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_bus_relations2 *bus_rel2;
 | |
| 	struct pci_dev_inval_block *inval;
 | |
| 	struct pci_dev_incoming *dev_message;
 | |
| 	struct hv_pci_dev *hpdev;
 | |
| 	unsigned long flags;
 | |
| 
 | |
| 	buffer = kmalloc(bufferlen, GFP_ATOMIC);
 | |
| 	if (!buffer)
 | |
| 		return;
 | |
| 
 | |
| 	while (1) {
 | |
| 		ret = vmbus_recvpacket_raw(chan, 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;
 | |
| 		}
 | |
| 
 | |
| 		/* Zero length indicates there are no more packets. */
 | |
| 		if (ret || !bytes_recvd)
 | |
| 			break;
 | |
| 
 | |
| 		/*
 | |
| 		 * All incoming packets must be at least as large as a
 | |
| 		 * response.
 | |
| 		 */
 | |
| 		if (bytes_recvd <= sizeof(struct pci_response))
 | |
| 			continue;
 | |
| 		desc = (struct vmpacket_descriptor *)buffer;
 | |
| 
 | |
| 		switch (desc->type) {
 | |
| 		case VM_PKT_COMP:
 | |
| 
 | |
| 			lock_requestor(chan, flags);
 | |
| 			req_addr = __vmbus_request_addr_match(chan, req_id,
 | |
| 							      VMBUS_RQST_ADDR_ANY);
 | |
| 			if (req_addr == VMBUS_RQST_ERROR) {
 | |
| 				unlock_requestor(chan, flags);
 | |
| 				dev_err(&hbus->hdev->device,
 | |
| 					"Invalid transaction ID %llx\n",
 | |
| 					req_id);
 | |
| 				break;
 | |
| 			}
 | |
| 			comp_packet = (struct pci_packet *)req_addr;
 | |
| 			response = (struct pci_response *)buffer;
 | |
| 			/*
 | |
| 			 * Call ->completion_func() within the critical section to make
 | |
| 			 * sure that the packet pointer is still valid during the call:
 | |
| 			 * here 'valid' means that there's a task still waiting for the
 | |
| 			 * completion, and that the packet data is still on the waiting
 | |
| 			 * task's stack.  Cf. hv_compose_msi_msg().
 | |
| 			 */
 | |
| 			comp_packet->completion_func(comp_packet->compl_ctxt,
 | |
| 						     response,
 | |
| 						     bytes_recvd);
 | |
| 			unlock_requestor(chan, flags);
 | |
| 			break;
 | |
| 
 | |
| 		case VM_PKT_DATA_INBAND:
 | |
| 
 | |
| 			new_message = (struct pci_incoming_message *)buffer;
 | |
| 			switch (new_message->message_type.type) {
 | |
| 			case PCI_BUS_RELATIONS:
 | |
| 
 | |
| 				bus_rel = (struct pci_bus_relations *)buffer;
 | |
| 				if (bytes_recvd < sizeof(*bus_rel) ||
 | |
| 				    bytes_recvd <
 | |
| 					struct_size(bus_rel, func,
 | |
| 						    bus_rel->device_count)) {
 | |
| 					dev_err(&hbus->hdev->device,
 | |
| 						"bus relations too small\n");
 | |
| 					break;
 | |
| 				}
 | |
| 
 | |
| 				hv_pci_devices_present(hbus, bus_rel);
 | |
| 				break;
 | |
| 
 | |
| 			case PCI_BUS_RELATIONS2:
 | |
| 
 | |
| 				bus_rel2 = (struct pci_bus_relations2 *)buffer;
 | |
| 				if (bytes_recvd < sizeof(*bus_rel2) ||
 | |
| 				    bytes_recvd <
 | |
| 					struct_size(bus_rel2, func,
 | |
| 						    bus_rel2->device_count)) {
 | |
| 					dev_err(&hbus->hdev->device,
 | |
| 						"bus relations v2 too small\n");
 | |
| 					break;
 | |
| 				}
 | |
| 
 | |
| 				hv_pci_devices_present2(hbus, bus_rel2);
 | |
| 				break;
 | |
| 
 | |
| 			case PCI_EJECT:
 | |
| 
 | |
| 				dev_message = (struct pci_dev_incoming *)buffer;
 | |
| 				if (bytes_recvd < sizeof(*dev_message)) {
 | |
| 					dev_err(&hbus->hdev->device,
 | |
| 						"eject message too small\n");
 | |
| 					break;
 | |
| 				}
 | |
| 				hpdev = get_pcichild_wslot(hbus,
 | |
| 						      dev_message->wslot.slot);
 | |
| 				if (hpdev) {
 | |
| 					hv_pci_eject_device(hpdev);
 | |
| 					put_pcichild(hpdev);
 | |
| 				}
 | |
| 				break;
 | |
| 
 | |
| 			case PCI_INVALIDATE_BLOCK:
 | |
| 
 | |
| 				inval = (struct pci_dev_inval_block *)buffer;
 | |
| 				if (bytes_recvd < sizeof(*inval)) {
 | |
| 					dev_err(&hbus->hdev->device,
 | |
| 						"invalidate message too small\n");
 | |
| 					break;
 | |
| 				}
 | |
| 				hpdev = get_pcichild_wslot(hbus,
 | |
| 							   inval->wslot.slot);
 | |
| 				if (hpdev) {
 | |
| 					if (hpdev->block_invalidate) {
 | |
| 						hpdev->block_invalidate(
 | |
| 						    hpdev->invalidate_context,
 | |
| 						    inval->block_mask);
 | |
| 					}
 | |
| 					put_pcichild(hpdev);
 | |
| 				}
 | |
| 				break;
 | |
| 
 | |
| 			default:
 | |
| 				dev_warn(&hbus->hdev->device,
 | |
| 					"Unimplemented protocol message %x\n",
 | |
| 					new_message->message_type.type);
 | |
| 				break;
 | |
| 			}
 | |
| 			break;
 | |
| 
 | |
| 		default:
 | |
| 			dev_err(&hbus->hdev->device,
 | |
| 				"unhandled packet type %d, tid %llx len %d\n",
 | |
| 				desc->type, req_id, bytes_recvd);
 | |
| 			break;
 | |
| 		}
 | |
| 	}
 | |
| 
 | |
| 	kfree(buffer);
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * hv_pci_protocol_negotiation() - Set up protocol
 | |
|  * @hdev:		VMBus's tracking struct for this root PCI bus.
 | |
|  * @version:		Array of supported channel protocol versions in
 | |
|  *			the order of probing - highest go first.
 | |
|  * @num_version:	Number of elements in the version array.
 | |
|  *
 | |
|  * 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,
 | |
| 				       enum pci_protocol_version_t version[],
 | |
| 				       int num_version)
 | |
| {
 | |
| 	struct hv_pcibus_device *hbus = hv_get_drvdata(hdev);
 | |
| 	struct pci_version_request *version_req;
 | |
| 	struct hv_pci_compl comp_pkt;
 | |
| 	struct pci_packet *pkt;
 | |
| 	int ret;
 | |
| 	int i;
 | |
| 
 | |
| 	/*
 | |
| 	 * Initiate the handshake 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.type = PCI_QUERY_PROTOCOL_VERSION;
 | |
| 
 | |
| 	for (i = 0; i < num_version; i++) {
 | |
| 		version_req->protocol_version = version[i];
 | |
| 		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)
 | |
| 			ret = wait_for_response(hdev, &comp_pkt.host_event);
 | |
| 
 | |
| 		if (ret) {
 | |
| 			dev_err(&hdev->device,
 | |
| 				"PCI Pass-through VSP failed to request version: %d",
 | |
| 				ret);
 | |
| 			goto exit;
 | |
| 		}
 | |
| 
 | |
| 		if (comp_pkt.completion_status >= 0) {
 | |
| 			hbus->protocol_version = version[i];
 | |
| 			dev_info(&hdev->device,
 | |
| 				"PCI VMBus probing: Using version %#x\n",
 | |
| 				hbus->protocol_version);
 | |
| 			goto exit;
 | |
| 		}
 | |
| 
 | |
| 		if (comp_pkt.completion_status != STATUS_REVISION_MISMATCH) {
 | |
| 			dev_err(&hdev->device,
 | |
| 				"PCI Pass-through VSP failed version request: %#x",
 | |
| 				comp_pkt.completion_status);
 | |
| 			ret = -EPROTO;
 | |
| 			goto exit;
 | |
| 		}
 | |
| 
 | |
| 		reinit_completion(&comp_pkt.host_event);
 | |
| 	}
 | |
| 
 | |
| 	dev_err(&hdev->device,
 | |
| 		"PCI pass-through VSP failed to find supported version");
 | |
| 	ret = -EPROTO;
 | |
| 
 | |
| 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)
 | |
| {
 | |
| 	/*
 | |
| 	 * Set the resources back to the way they looked when they
 | |
| 	 * were allocated by setting IORESOURCE_BUSY again.
 | |
| 	 */
 | |
| 
 | |
| 	if (hbus->low_mmio_space && hbus->low_mmio_res) {
 | |
| 		hbus->low_mmio_res->flags |= IORESOURCE_BUSY;
 | |
| 		vmbus_free_mmio(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;
 | |
| 		vmbus_free_mmio(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
 | |
|  *
 | |
|  * This function calls vmbus_allocate_mmio(), which is itself a
 | |
|  * bit of a compromise.  Ideally, we might change the pnp layer
 | |
|  * in the kernel such that it comprehends either PCI devices
 | |
|  * which are "grandchildren of ACPI," with some intermediate bus
 | |
|  * node (in this case, VMBus) or change it such that it
 | |
|  * understands VMBus.  The pnp layer, however, has been declared
 | |
|  * deprecated, and not subject to change.
 | |
|  *
 | |
|  * The workaround, implemented here, is to ask VMBus to allocate
 | |
|  * MMIO space for this bus.  VMBus itself knows which ranges are
 | |
|  * appropriate by looking at its own ACPI objects.  Then, after
 | |
|  * these ranges are claimed, they're modified to look like they
 | |
|  * would have looked if the ACPI and pnp code had allocated
 | |
|  * bridge windows.  These descriptors have to exist in this form
 | |
|  * in order to satisfy the code which will get invoked when the
 | |
|  * endpoint PCI function driver calls request_mem_region() or
 | |
|  * request_mem_region_exclusive().
 | |
|  *
 | |
|  * 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 = 1ULL << (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) {
 | |
| 			dev_err(&hbus->hdev->device,
 | |
| 				"Need %#llx of low MMIO space. Consider reconfiguring the VM.\n",
 | |
| 				hbus->low_mmio_space);
 | |
| 			return ret;
 | |
| 		}
 | |
| 
 | |
| 		/* Modify this resource to become a bridge window. */
 | |
| 		hbus->low_mmio_res->flags |= IORESOURCE_WINDOW;
 | |
| 		hbus->low_mmio_res->flags &= ~IORESOURCE_BUSY;
 | |
| 		pci_add_resource(&hbus->bridge->windows, hbus->low_mmio_res);
 | |
| 	}
 | |
| 
 | |
| 	if (hbus->high_mmio_space) {
 | |
| 		align = 1ULL << (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) {
 | |
| 			dev_err(&hbus->hdev->device,
 | |
| 				"Need %#llx of high MMIO space. Consider reconfiguring the VM.\n",
 | |
| 				hbus->high_mmio_space);
 | |
| 			goto release_low_mmio;
 | |
| 		}
 | |
| 
 | |
| 		/* Modify this resource to become a bridge window. */
 | |
| 		hbus->high_mmio_res->flags |= IORESOURCE_WINDOW;
 | |
| 		hbus->high_mmio_res->flags &= ~IORESOURCE_BUSY;
 | |
| 		pci_add_resource(&hbus->bridge->windows, hbus->high_mmio_res);
 | |
| 	}
 | |
| 
 | |
| 	return 0;
 | |
| 
 | |
| release_low_mmio:
 | |
| 	if (hbus->low_mmio_res) {
 | |
| 		vmbus_free_mmio(hbus->low_mmio_res->start,
 | |
| 				resource_size(hbus->low_mmio_res));
 | |
| 	}
 | |
| 
 | |
| 	return ret;
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * hv_allocate_config_window() - Find MMIO space for PCI Config
 | |
|  * @hbus:	Root PCI bus, as understood by this driver
 | |
|  *
 | |
|  * This function claims memory-mapped I/O space for accessing
 | |
|  * configuration space for the functions on this bus.
 | |
|  *
 | |
|  * Return: 0 on success, -errno on failure
 | |
|  */
 | |
| static int hv_allocate_config_window(struct hv_pcibus_device *hbus)
 | |
| {
 | |
| 	int ret;
 | |
| 
 | |
| 	/*
 | |
| 	 * Set up a region of MMIO space to use for accessing configuration
 | |
| 	 * space.
 | |
| 	 */
 | |
| 	ret = vmbus_allocate_mmio(&hbus->mem_config, hbus->hdev, 0, -1,
 | |
| 				  PCI_CONFIG_MMIO_LENGTH, 0x1000, false);
 | |
| 	if (ret)
 | |
| 		return ret;
 | |
| 
 | |
| 	/*
 | |
| 	 * vmbus_allocate_mmio() gets used for allocating both device endpoint
 | |
| 	 * resource claims (those which cannot be overlapped) and the ranges
 | |
| 	 * which are valid for the children of this bus, which are intended
 | |
| 	 * to be overlapped by those children.  Set the flag on this claim
 | |
| 	 * meaning that this region can't be overlapped.
 | |
| 	 */
 | |
| 
 | |
| 	hbus->mem_config->flags |= IORESOURCE_BUSY;
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static void hv_free_config_window(struct hv_pcibus_device *hbus)
 | |
| {
 | |
| 	vmbus_free_mmio(hbus->mem_config->start, PCI_CONFIG_MMIO_LENGTH);
 | |
| }
 | |
| 
 | |
| static int hv_pci_bus_exit(struct hv_device *hdev, bool keep_devs);
 | |
| 
 | |
| /**
 | |
|  * 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;
 | |
| 	bool retry = true;
 | |
| 	int ret;
 | |
| 
 | |
| enter_d0_retry:
 | |
| 	/*
 | |
| 	 * 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.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)
 | |
| 		ret = wait_for_response(hdev, &comp_pkt.host_event);
 | |
| 
 | |
| 	if (ret)
 | |
| 		goto exit;
 | |
| 
 | |
| 	/*
 | |
| 	 * In certain case (Kdump) the pci device of interest was
 | |
| 	 * not cleanly shut down and resource is still held on host
 | |
| 	 * side, the host could return invalid device status.
 | |
| 	 * We need to explicitly request host to release the resource
 | |
| 	 * and try to enter D0 again.
 | |
| 	 */
 | |
| 	if (comp_pkt.completion_status < 0 && retry) {
 | |
| 		retry = false;
 | |
| 
 | |
| 		dev_err(&hdev->device, "Retrying D0 Entry\n");
 | |
| 
 | |
| 		/*
 | |
| 		 * Hv_pci_bus_exit() calls hv_send_resource_released()
 | |
| 		 * to free up resources of its child devices.
 | |
| 		 * In the kdump kernel we need to set the
 | |
| 		 * wslot_res_allocated to 255 so it scans all child
 | |
| 		 * devices to release resources allocated in the
 | |
| 		 * normal kernel before panic happened.
 | |
| 		 */
 | |
| 		hbus->wslot_res_allocated = 255;
 | |
| 
 | |
| 		ret = hv_pci_bus_exit(hdev, true);
 | |
| 
 | |
| 		if (ret == 0) {
 | |
| 			kfree(pkt);
 | |
| 			goto enter_d0_retry;
 | |
| 		}
 | |
| 		dev_err(&hdev->device,
 | |
| 			"Retrying D0 failed with ret %d\n", ret);
 | |
| 	}
 | |
| 
 | |
| 	if (comp_pkt.completion_status < 0) {
 | |
| 		dev_err(&hdev->device,
 | |
| 			"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.type = PCI_QUERY_BUS_RELATIONS;
 | |
| 
 | |
| 	ret = vmbus_sendpacket(hdev->channel, &message, sizeof(message),
 | |
| 			       0, VM_PKT_DATA_INBAND, 0);
 | |
| 	if (!ret)
 | |
| 		ret = wait_for_response(hdev, &comp);
 | |
| 
 | |
| 	/*
 | |
| 	 * In the case of fast device addition/removal, it's possible that
 | |
| 	 * vmbus_sendpacket() or wait_for_response() returns -ENODEV but we
 | |
| 	 * already got a PCI_BUS_RELATIONS* message from the host and the
 | |
| 	 * channel callback already scheduled a work to hbus->wq, which can be
 | |
| 	 * running pci_devices_present_work() -> survey_child_resources() ->
 | |
| 	 * complete(&hbus->survey_event), even after hv_pci_query_relations()
 | |
| 	 * exits and the stack variable 'comp' is no longer valid; as a result,
 | |
| 	 * a hang or a page fault may happen when the complete() calls
 | |
| 	 * raw_spin_lock_irqsave(). Flush hbus->wq before we exit from
 | |
| 	 * hv_pci_query_relations() to avoid the issues. Note: if 'ret' is
 | |
| 	 * -ENODEV, there can't be any more work item scheduled to hbus->wq
 | |
| 	 * after the flush_workqueue(): see vmbus_onoffer_rescind() ->
 | |
| 	 * vmbus_reset_channel_cb(), vmbus_rescind_cleanup() ->
 | |
| 	 * channel->rescind = true.
 | |
| 	 */
 | |
| 	flush_workqueue(hbus->wq);
 | |
| 
 | |
| 	return ret;
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * 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 pci_resources_assigned2 *res_assigned2;
 | |
| 	struct hv_pci_compl comp_pkt;
 | |
| 	struct hv_pci_dev *hpdev;
 | |
| 	struct pci_packet *pkt;
 | |
| 	size_t size_res;
 | |
| 	int wslot;
 | |
| 	int ret;
 | |
| 
 | |
| 	size_res = (hbus->protocol_version < PCI_PROTOCOL_VERSION_1_2)
 | |
| 			? sizeof(*res_assigned) : sizeof(*res_assigned2);
 | |
| 
 | |
| 	pkt = kmalloc(sizeof(*pkt) + size_res, GFP_KERNEL);
 | |
| 	if (!pkt)
 | |
| 		return -ENOMEM;
 | |
| 
 | |
| 	ret = 0;
 | |
| 
 | |
| 	for (wslot = 0; wslot < 256; wslot++) {
 | |
| 		hpdev = get_pcichild_wslot(hbus, wslot);
 | |
| 		if (!hpdev)
 | |
| 			continue;
 | |
| 
 | |
| 		memset(pkt, 0, sizeof(*pkt) + size_res);
 | |
| 		init_completion(&comp_pkt.host_event);
 | |
| 		pkt->completion_func = hv_pci_generic_compl;
 | |
| 		pkt->compl_ctxt = &comp_pkt;
 | |
| 
 | |
| 		if (hbus->protocol_version < PCI_PROTOCOL_VERSION_1_2) {
 | |
| 			res_assigned =
 | |
| 				(struct pci_resources_assigned *)&pkt->message;
 | |
| 			res_assigned->message_type.type =
 | |
| 				PCI_RESOURCES_ASSIGNED;
 | |
| 			res_assigned->wslot.slot = hpdev->desc.win_slot.slot;
 | |
| 		} else {
 | |
| 			res_assigned2 =
 | |
| 				(struct pci_resources_assigned2 *)&pkt->message;
 | |
| 			res_assigned2->message_type.type =
 | |
| 				PCI_RESOURCES_ASSIGNED2;
 | |
| 			res_assigned2->wslot.slot = hpdev->desc.win_slot.slot;
 | |
| 		}
 | |
| 		put_pcichild(hpdev);
 | |
| 
 | |
| 		ret = vmbus_sendpacket(hdev->channel, &pkt->message,
 | |
| 				size_res, (unsigned long)pkt,
 | |
| 				VM_PKT_DATA_INBAND,
 | |
| 				VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 | |
| 		if (!ret)
 | |
| 			ret = wait_for_response(hdev, &comp_pkt.host_event);
 | |
| 		if (ret)
 | |
| 			break;
 | |
| 
 | |
| 		if (comp_pkt.completion_status < 0) {
 | |
| 			ret = -EPROTO;
 | |
| 			dev_err(&hdev->device,
 | |
| 				"resource allocated returned 0x%x",
 | |
| 				comp_pkt.completion_status);
 | |
| 			break;
 | |
| 		}
 | |
| 
 | |
| 		hbus->wslot_res_allocated = wslot;
 | |
| 	}
 | |
| 
 | |
| 	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;
 | |
| 	int wslot;
 | |
| 	int ret;
 | |
| 
 | |
| 	for (wslot = hbus->wslot_res_allocated; wslot >= 0; wslot--) {
 | |
| 		hpdev = get_pcichild_wslot(hbus, wslot);
 | |
| 		if (!hpdev)
 | |
| 			continue;
 | |
| 
 | |
| 		memset(&pkt, 0, sizeof(pkt));
 | |
| 		pkt.message_type.type = PCI_RESOURCES_RELEASED;
 | |
| 		pkt.wslot.slot = hpdev->desc.win_slot.slot;
 | |
| 
 | |
| 		put_pcichild(hpdev);
 | |
| 
 | |
| 		ret = vmbus_sendpacket(hdev->channel, &pkt, sizeof(pkt), 0,
 | |
| 				       VM_PKT_DATA_INBAND, 0);
 | |
| 		if (ret)
 | |
| 			return ret;
 | |
| 
 | |
| 		hbus->wslot_res_allocated = wslot - 1;
 | |
| 	}
 | |
| 
 | |
| 	hbus->wslot_res_allocated = -1;
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| #define HVPCI_DOM_MAP_SIZE (64 * 1024)
 | |
| static DECLARE_BITMAP(hvpci_dom_map, HVPCI_DOM_MAP_SIZE);
 | |
| 
 | |
| /*
 | |
|  * PCI domain number 0 is used by emulated devices on Gen1 VMs, so define 0
 | |
|  * as invalid for passthrough PCI devices of this driver.
 | |
|  */
 | |
| #define HVPCI_DOM_INVALID 0
 | |
| 
 | |
| /**
 | |
|  * hv_get_dom_num() - Get a valid PCI domain number
 | |
|  * Check if the PCI domain number is in use, and return another number if
 | |
|  * it is in use.
 | |
|  *
 | |
|  * @dom: Requested domain number
 | |
|  *
 | |
|  * return: domain number on success, HVPCI_DOM_INVALID on failure
 | |
|  */
 | |
| static u16 hv_get_dom_num(u16 dom)
 | |
| {
 | |
| 	unsigned int i;
 | |
| 
 | |
| 	if (test_and_set_bit(dom, hvpci_dom_map) == 0)
 | |
| 		return dom;
 | |
| 
 | |
| 	for_each_clear_bit(i, hvpci_dom_map, HVPCI_DOM_MAP_SIZE) {
 | |
| 		if (test_and_set_bit(i, hvpci_dom_map) == 0)
 | |
| 			return i;
 | |
| 	}
 | |
| 
 | |
| 	return HVPCI_DOM_INVALID;
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * hv_put_dom_num() - Mark the PCI domain number as free
 | |
|  * @dom: Domain number to be freed
 | |
|  */
 | |
| static void hv_put_dom_num(u16 dom)
 | |
| {
 | |
| 	clear_bit(dom, hvpci_dom_map);
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * hv_pci_probe() - New VMBus channel probe, for a root PCI bus
 | |
|  * @hdev:	VMBus's tracking struct for this root PCI bus
 | |
|  * @dev_id:	Identifies 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 pci_host_bridge *bridge;
 | |
| 	struct hv_pcibus_device *hbus;
 | |
| 	u16 dom_req, dom;
 | |
| 	char *name;
 | |
| 	int ret;
 | |
| 
 | |
| 	bridge = devm_pci_alloc_host_bridge(&hdev->device, 0);
 | |
| 	if (!bridge)
 | |
| 		return -ENOMEM;
 | |
| 
 | |
| 	hbus = kzalloc(sizeof(*hbus), GFP_KERNEL);
 | |
| 	if (!hbus)
 | |
| 		return -ENOMEM;
 | |
| 
 | |
| 	hbus->bridge = bridge;
 | |
| 	mutex_init(&hbus->state_lock);
 | |
| 	hbus->state = hv_pcibus_init;
 | |
| 	hbus->wslot_res_allocated = -1;
 | |
| 
 | |
| 	/*
 | |
| 	 * The PCI bus "domain" is what is called "segment" in ACPI and other
 | |
| 	 * specs. Pull it from the instance ID, to get something usually
 | |
| 	 * unique. In rare cases of collision, we will find out another number
 | |
| 	 * not in use.
 | |
| 	 *
 | |
| 	 * Note that, since this code only runs in a Hyper-V VM, Hyper-V
 | |
| 	 * together with this guest driver can guarantee that (1) The only
 | |
| 	 * domain used by Gen1 VMs for something that looks like a physical
 | |
| 	 * PCI bus (which is actually emulated by the hypervisor) is domain 0.
 | |
| 	 * (2) There will be no overlap between domains (after fixing possible
 | |
| 	 * collisions) in the same VM.
 | |
| 	 */
 | |
| 	dom_req = hdev->dev_instance.b[5] << 8 | hdev->dev_instance.b[4];
 | |
| 	dom = hv_get_dom_num(dom_req);
 | |
| 
 | |
| 	if (dom == HVPCI_DOM_INVALID) {
 | |
| 		dev_err(&hdev->device,
 | |
| 			"Unable to use dom# 0x%x or other numbers", dom_req);
 | |
| 		ret = -EINVAL;
 | |
| 		goto free_bus;
 | |
| 	}
 | |
| 
 | |
| 	if (dom != dom_req)
 | |
| 		dev_info(&hdev->device,
 | |
| 			 "PCI dom# 0x%x has collision, using 0x%x",
 | |
| 			 dom_req, dom);
 | |
| 
 | |
| 	hbus->bridge->domain_nr = dom;
 | |
| #ifdef CONFIG_X86
 | |
| 	hbus->sysdata.domain = dom;
 | |
| 	hbus->use_calls = !!(ms_hyperv.hints & HV_X64_USE_MMIO_HYPERCALLS);
 | |
| #elif defined(CONFIG_ARM64)
 | |
| 	/*
 | |
| 	 * Set the PCI bus parent to be the corresponding VMbus
 | |
| 	 * device. Then the VMbus device will be assigned as the
 | |
| 	 * ACPI companion in pcibios_root_bridge_prepare() and
 | |
| 	 * pci_dma_configure() will propagate device coherence
 | |
| 	 * information to devices created on the bus.
 | |
| 	 */
 | |
| 	hbus->sysdata.parent = hdev->device.parent;
 | |
| 	hbus->use_calls = false;
 | |
| #endif
 | |
| 
 | |
| 	hbus->hdev = hdev;
 | |
| 	INIT_LIST_HEAD(&hbus->children);
 | |
| 	INIT_LIST_HEAD(&hbus->dr_list);
 | |
| 	spin_lock_init(&hbus->config_lock);
 | |
| 	spin_lock_init(&hbus->device_list_lock);
 | |
| 	hbus->wq = alloc_ordered_workqueue("hv_pci_%x", 0,
 | |
| 					   hbus->bridge->domain_nr);
 | |
| 	if (!hbus->wq) {
 | |
| 		ret = -ENOMEM;
 | |
| 		goto free_dom;
 | |
| 	}
 | |
| 
 | |
| 	hdev->channel->next_request_id_callback = vmbus_next_request_id;
 | |
| 	hdev->channel->request_addr_callback = vmbus_request_addr;
 | |
| 	hdev->channel->rqstor_size = HV_PCI_RQSTOR_SIZE;
 | |
| 
 | |
| 	ret = vmbus_open(hdev->channel, pci_ring_size, pci_ring_size, NULL, 0,
 | |
| 			 hv_pci_onchannelcallback, hbus);
 | |
| 	if (ret)
 | |
| 		goto destroy_wq;
 | |
| 
 | |
| 	hv_set_drvdata(hdev, hbus);
 | |
| 
 | |
| 	ret = hv_pci_protocol_negotiation(hdev, pci_protocol_versions,
 | |
| 					  ARRAY_SIZE(pci_protocol_versions));
 | |
| 	if (ret)
 | |
| 		goto close;
 | |
| 
 | |
| 	ret = hv_allocate_config_window(hbus);
 | |
| 	if (ret)
 | |
| 		goto close;
 | |
| 
 | |
| 	hbus->cfg_addr = ioremap(hbus->mem_config->start,
 | |
| 				 PCI_CONFIG_MMIO_LENGTH);
 | |
| 	if (!hbus->cfg_addr) {
 | |
| 		dev_err(&hdev->device,
 | |
| 			"Unable to map a virtual address for config space\n");
 | |
| 		ret = -ENOMEM;
 | |
| 		goto free_config;
 | |
| 	}
 | |
| 
 | |
| 	name = kasprintf(GFP_KERNEL, "%pUL", &hdev->dev_instance);
 | |
| 	if (!name) {
 | |
| 		ret = -ENOMEM;
 | |
| 		goto unmap;
 | |
| 	}
 | |
| 
 | |
| 	hbus->fwnode = irq_domain_alloc_named_fwnode(name);
 | |
| 	kfree(name);
 | |
| 	if (!hbus->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;
 | |
| 
 | |
| 	mutex_lock(&hbus->state_lock);
 | |
| 
 | |
| 	ret = hv_pci_enter_d0(hdev);
 | |
| 	if (ret)
 | |
| 		goto release_state_lock;
 | |
| 
 | |
| 	ret = hv_pci_allocate_bridge_windows(hbus);
 | |
| 	if (ret)
 | |
| 		goto exit_d0;
 | |
| 
 | |
| 	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;
 | |
| 
 | |
| 	mutex_unlock(&hbus->state_lock);
 | |
| 	return 0;
 | |
| 
 | |
| free_windows:
 | |
| 	hv_pci_free_bridge_windows(hbus);
 | |
| exit_d0:
 | |
| 	(void) hv_pci_bus_exit(hdev, true);
 | |
| release_state_lock:
 | |
| 	mutex_unlock(&hbus->state_lock);
 | |
| free_irq_domain:
 | |
| 	irq_domain_remove(hbus->irq_domain);
 | |
| free_fwnode:
 | |
| 	irq_domain_free_fwnode(hbus->fwnode);
 | |
| unmap:
 | |
| 	iounmap(hbus->cfg_addr);
 | |
| free_config:
 | |
| 	hv_free_config_window(hbus);
 | |
| close:
 | |
| 	vmbus_close(hdev->channel);
 | |
| destroy_wq:
 | |
| 	destroy_workqueue(hbus->wq);
 | |
| free_dom:
 | |
| 	hv_put_dom_num(hbus->bridge->domain_nr);
 | |
| free_bus:
 | |
| 	kfree(hbus);
 | |
| 	return ret;
 | |
| }
 | |
| 
 | |
| static int hv_pci_bus_exit(struct hv_device *hdev, bool keep_devs)
 | |
| {
 | |
| 	struct hv_pcibus_device *hbus = hv_get_drvdata(hdev);
 | |
| 	struct vmbus_channel *chan = hdev->channel;
 | |
| 	struct {
 | |
| 		struct pci_packet teardown_packet;
 | |
| 		u8 buffer[sizeof(struct pci_message)];
 | |
| 	} pkt;
 | |
| 	struct hv_pci_compl comp_pkt;
 | |
| 	struct hv_pci_dev *hpdev, *tmp;
 | |
| 	unsigned long flags;
 | |
| 	u64 trans_id;
 | |
| 	int ret;
 | |
| 
 | |
| 	/*
 | |
| 	 * After the host sends the RESCIND_CHANNEL message, it doesn't
 | |
| 	 * access the per-channel ringbuffer any longer.
 | |
| 	 */
 | |
| 	if (chan->rescind)
 | |
| 		return 0;
 | |
| 
 | |
| 	if (!keep_devs) {
 | |
| 		struct list_head removed;
 | |
| 
 | |
| 		/* Move all present children to the list on stack */
 | |
| 		INIT_LIST_HEAD(&removed);
 | |
| 		spin_lock_irqsave(&hbus->device_list_lock, flags);
 | |
| 		list_for_each_entry_safe(hpdev, tmp, &hbus->children, list_entry)
 | |
| 			list_move_tail(&hpdev->list_entry, &removed);
 | |
| 		spin_unlock_irqrestore(&hbus->device_list_lock, flags);
 | |
| 
 | |
| 		/* Remove all children in the list */
 | |
| 		list_for_each_entry_safe(hpdev, tmp, &removed, list_entry) {
 | |
| 			list_del(&hpdev->list_entry);
 | |
| 			if (hpdev->pci_slot)
 | |
| 				pci_destroy_slot(hpdev->pci_slot);
 | |
| 			/* For the two refs got in new_pcichild_device() */
 | |
| 			put_pcichild(hpdev);
 | |
| 			put_pcichild(hpdev);
 | |
| 		}
 | |
| 	}
 | |
| 
 | |
| 	ret = hv_send_resources_released(hdev);
 | |
| 	if (ret) {
 | |
| 		dev_err(&hdev->device,
 | |
| 			"Couldn't send resources released packet(s)\n");
 | |
| 		return ret;
 | |
| 	}
 | |
| 
 | |
| 	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[0].type = PCI_BUS_D0EXIT;
 | |
| 
 | |
| 	ret = vmbus_sendpacket_getid(chan, &pkt.teardown_packet.message,
 | |
| 				     sizeof(struct pci_message),
 | |
| 				     (unsigned long)&pkt.teardown_packet,
 | |
| 				     &trans_id, VM_PKT_DATA_INBAND,
 | |
| 				     VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 | |
| 	if (ret)
 | |
| 		return ret;
 | |
| 
 | |
| 	if (wait_for_completion_timeout(&comp_pkt.host_event, 10 * HZ) == 0) {
 | |
| 		/*
 | |
| 		 * The completion packet on the stack becomes invalid after
 | |
| 		 * 'return'; remove the ID from the VMbus requestor if the
 | |
| 		 * identifier is still mapped to/associated with the packet.
 | |
| 		 *
 | |
| 		 * Cf. hv_pci_onchannelcallback().
 | |
| 		 */
 | |
| 		vmbus_request_addr_match(chan, trans_id,
 | |
| 					 (unsigned long)&pkt.teardown_packet);
 | |
| 		return -ETIMEDOUT;
 | |
| 	}
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * hv_pci_remove() - Remove routine for this VMBus channel
 | |
|  * @hdev:	VMBus's tracking struct for this root PCI bus
 | |
|  */
 | |
| static void hv_pci_remove(struct hv_device *hdev)
 | |
| {
 | |
| 	struct hv_pcibus_device *hbus;
 | |
| 
 | |
| 	hbus = hv_get_drvdata(hdev);
 | |
| 	if (hbus->state == hv_pcibus_installed) {
 | |
| 		tasklet_disable(&hdev->channel->callback_event);
 | |
| 		hbus->state = hv_pcibus_removing;
 | |
| 		tasklet_enable(&hdev->channel->callback_event);
 | |
| 		destroy_workqueue(hbus->wq);
 | |
| 		hbus->wq = NULL;
 | |
| 		/*
 | |
| 		 * At this point, no work is running or can be scheduled
 | |
| 		 * on hbus-wq. We can't race with hv_pci_devices_present()
 | |
| 		 * or hv_pci_eject_device(), it's safe to proceed.
 | |
| 		 */
 | |
| 
 | |
| 		/* Remove the bus from PCI's point of view. */
 | |
| 		pci_lock_rescan_remove();
 | |
| 		pci_stop_root_bus(hbus->bridge->bus);
 | |
| 		hv_pci_remove_slots(hbus);
 | |
| 		pci_remove_root_bus(hbus->bridge->bus);
 | |
| 		pci_unlock_rescan_remove();
 | |
| 	}
 | |
| 
 | |
| 	hv_pci_bus_exit(hdev, false);
 | |
| 
 | |
| 	vmbus_close(hdev->channel);
 | |
| 
 | |
| 	iounmap(hbus->cfg_addr);
 | |
| 	hv_free_config_window(hbus);
 | |
| 	hv_pci_free_bridge_windows(hbus);
 | |
| 	irq_domain_remove(hbus->irq_domain);
 | |
| 	irq_domain_free_fwnode(hbus->fwnode);
 | |
| 
 | |
| 	hv_put_dom_num(hbus->bridge->domain_nr);
 | |
| 
 | |
| 	kfree(hbus);
 | |
| }
 | |
| 
 | |
| static int hv_pci_suspend(struct hv_device *hdev)
 | |
| {
 | |
| 	struct hv_pcibus_device *hbus = hv_get_drvdata(hdev);
 | |
| 	enum hv_pcibus_state old_state;
 | |
| 	int ret;
 | |
| 
 | |
| 	/*
 | |
| 	 * hv_pci_suspend() must make sure there are no pending work items
 | |
| 	 * before calling vmbus_close(), since it runs in a process context
 | |
| 	 * as a callback in dpm_suspend().  When it starts to run, the channel
 | |
| 	 * callback hv_pci_onchannelcallback(), which runs in a tasklet
 | |
| 	 * context, can be still running concurrently and scheduling new work
 | |
| 	 * items onto hbus->wq in hv_pci_devices_present() and
 | |
| 	 * hv_pci_eject_device(), and the work item handlers can access the
 | |
| 	 * vmbus channel, which can be being closed by hv_pci_suspend(), e.g.
 | |
| 	 * the work item handler pci_devices_present_work() ->
 | |
| 	 * new_pcichild_device() writes to the vmbus channel.
 | |
| 	 *
 | |
| 	 * To eliminate the race, hv_pci_suspend() disables the channel
 | |
| 	 * callback tasklet, sets hbus->state to hv_pcibus_removing, and
 | |
| 	 * re-enables the tasklet. This way, when hv_pci_suspend() proceeds,
 | |
| 	 * it knows that no new work item can be scheduled, and then it flushes
 | |
| 	 * hbus->wq and safely closes the vmbus channel.
 | |
| 	 */
 | |
| 	tasklet_disable(&hdev->channel->callback_event);
 | |
| 
 | |
| 	/* Change the hbus state to prevent new work items. */
 | |
| 	old_state = hbus->state;
 | |
| 	if (hbus->state == hv_pcibus_installed)
 | |
| 		hbus->state = hv_pcibus_removing;
 | |
| 
 | |
| 	tasklet_enable(&hdev->channel->callback_event);
 | |
| 
 | |
| 	if (old_state != hv_pcibus_installed)
 | |
| 		return -EINVAL;
 | |
| 
 | |
| 	flush_workqueue(hbus->wq);
 | |
| 
 | |
| 	ret = hv_pci_bus_exit(hdev, true);
 | |
| 	if (ret)
 | |
| 		return ret;
 | |
| 
 | |
| 	vmbus_close(hdev->channel);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static int hv_pci_restore_msi_msg(struct pci_dev *pdev, void *arg)
 | |
| {
 | |
| 	struct irq_data *irq_data;
 | |
| 	struct msi_desc *entry;
 | |
| 	int ret = 0;
 | |
| 
 | |
| 	if (!pdev->msi_enabled && !pdev->msix_enabled)
 | |
| 		return 0;
 | |
| 
 | |
| 	msi_lock_descs(&pdev->dev);
 | |
| 	msi_for_each_desc(entry, &pdev->dev, MSI_DESC_ASSOCIATED) {
 | |
| 		irq_data = irq_get_irq_data(entry->irq);
 | |
| 		if (WARN_ON_ONCE(!irq_data)) {
 | |
| 			ret = -EINVAL;
 | |
| 			break;
 | |
| 		}
 | |
| 
 | |
| 		hv_compose_msi_msg(irq_data, &entry->msg);
 | |
| 	}
 | |
| 	msi_unlock_descs(&pdev->dev);
 | |
| 
 | |
| 	return ret;
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Upon resume, pci_restore_msi_state() -> ... ->  __pci_write_msi_msg()
 | |
|  * directly writes the MSI/MSI-X registers via MMIO, but since Hyper-V
 | |
|  * doesn't trap and emulate the MMIO accesses, here hv_compose_msi_msg()
 | |
|  * must be used to ask Hyper-V to re-create the IOMMU Interrupt Remapping
 | |
|  * Table entries.
 | |
|  */
 | |
| static void hv_pci_restore_msi_state(struct hv_pcibus_device *hbus)
 | |
| {
 | |
| 	pci_walk_bus(hbus->bridge->bus, hv_pci_restore_msi_msg, NULL);
 | |
| }
 | |
| 
 | |
| static int hv_pci_resume(struct hv_device *hdev)
 | |
| {
 | |
| 	struct hv_pcibus_device *hbus = hv_get_drvdata(hdev);
 | |
| 	enum pci_protocol_version_t version[1];
 | |
| 	int ret;
 | |
| 
 | |
| 	hbus->state = hv_pcibus_init;
 | |
| 
 | |
| 	hdev->channel->next_request_id_callback = vmbus_next_request_id;
 | |
| 	hdev->channel->request_addr_callback = vmbus_request_addr;
 | |
| 	hdev->channel->rqstor_size = HV_PCI_RQSTOR_SIZE;
 | |
| 
 | |
| 	ret = vmbus_open(hdev->channel, pci_ring_size, pci_ring_size, NULL, 0,
 | |
| 			 hv_pci_onchannelcallback, hbus);
 | |
| 	if (ret)
 | |
| 		return ret;
 | |
| 
 | |
| 	/* Only use the version that was in use before hibernation. */
 | |
| 	version[0] = hbus->protocol_version;
 | |
| 	ret = hv_pci_protocol_negotiation(hdev, version, 1);
 | |
| 	if (ret)
 | |
| 		goto out;
 | |
| 
 | |
| 	ret = hv_pci_query_relations(hdev);
 | |
| 	if (ret)
 | |
| 		goto out;
 | |
| 
 | |
| 	mutex_lock(&hbus->state_lock);
 | |
| 
 | |
| 	ret = hv_pci_enter_d0(hdev);
 | |
| 	if (ret)
 | |
| 		goto release_state_lock;
 | |
| 
 | |
| 	ret = hv_send_resources_allocated(hdev);
 | |
| 	if (ret)
 | |
| 		goto release_state_lock;
 | |
| 
 | |
| 	prepopulate_bars(hbus);
 | |
| 
 | |
| 	hv_pci_restore_msi_state(hbus);
 | |
| 
 | |
| 	hbus->state = hv_pcibus_installed;
 | |
| 	mutex_unlock(&hbus->state_lock);
 | |
| 	return 0;
 | |
| 
 | |
| release_state_lock:
 | |
| 	mutex_unlock(&hbus->state_lock);
 | |
| out:
 | |
| 	vmbus_close(hdev->channel);
 | |
| 	return ret;
 | |
| }
 | |
| 
 | |
| 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,
 | |
| 	.suspend	= hv_pci_suspend,
 | |
| 	.resume		= hv_pci_resume,
 | |
| };
 | |
| 
 | |
| static void __exit exit_hv_pci_drv(void)
 | |
| {
 | |
| 	vmbus_driver_unregister(&hv_pci_drv);
 | |
| 
 | |
| 	hvpci_block_ops.read_block = NULL;
 | |
| 	hvpci_block_ops.write_block = NULL;
 | |
| 	hvpci_block_ops.reg_blk_invalidate = NULL;
 | |
| }
 | |
| 
 | |
| static int __init init_hv_pci_drv(void)
 | |
| {
 | |
| 	int ret;
 | |
| 
 | |
| 	if (!hv_is_hyperv_initialized())
 | |
| 		return -ENODEV;
 | |
| 
 | |
| 	ret = hv_pci_irqchip_init();
 | |
| 	if (ret)
 | |
| 		return ret;
 | |
| 
 | |
| 	/* Set the invalid domain number's bit, so it will not be used */
 | |
| 	set_bit(HVPCI_DOM_INVALID, hvpci_dom_map);
 | |
| 
 | |
| 	/* Initialize PCI block r/w interface */
 | |
| 	hvpci_block_ops.read_block = hv_read_config_block;
 | |
| 	hvpci_block_ops.write_block = hv_write_config_block;
 | |
| 	hvpci_block_ops.reg_blk_invalidate = hv_register_block_invalidate;
 | |
| 
 | |
| 	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");
 |