2 * Copyright (c) Microsoft Corporation.
5 * Jake Oshins <jakeo@microsoft.com>
7 * This driver acts as a paravirtual front-end for PCI Express root buses.
8 * When a PCI Express function (either an entire device or an SR-IOV
9 * Virtual Function) is being passed through to the VM, this driver exposes
10 * a new bus to the guest VM. This is modeled as a root PCI bus because
11 * no bridges are being exposed to the VM. In fact, with a "Generation 2"
12 * VM within Hyper-V, there may seem to be no PCI bus at all in the VM
13 * until a device as been exposed using this driver.
15 * Each root PCI bus has its own PCI domain, which is called "Segment" in
16 * the PCI Firmware Specifications. Thus while each device passed through
17 * to the VM using this front-end will appear at "device 0", the domain will
18 * be unique. Typically, each bus will have one PCI function on it, though
19 * this driver does support more than one.
21 * In order to map the interrupts from the device through to the guest VM,
22 * this driver also implements an IRQ Domain, which handles interrupts (either
23 * MSI or MSI-X) associated with the functions on the bus. As interrupts are
24 * set up, torn down, or reaffined, this driver communicates with the
25 * underlying hypervisor to adjust the mappings in the I/O MMU so that each
26 * interrupt will be delivered to the correct virtual processor at the right
27 * vector. This driver does not support level-triggered (line-based)
28 * interrupts, and will report that the Interrupt Line register in the
29 * function's configuration space is zero.
31 * The rest of this driver mostly maps PCI concepts onto underlying Hyper-V
32 * facilities. For instance, the configuration space of a function exposed
33 * by Hyper-V is mapped into a single page of memory space, and the
34 * read and write handlers for config space must be aware of this mechanism.
35 * Similarly, device setup and teardown involves messages sent to and from
36 * the PCI back-end driver in Hyper-V.
38 * This program is free software; you can redistribute it and/or modify it
39 * under the terms of the GNU General Public License version 2 as published
40 * by the Free Software Foundation.
42 * This program is distributed in the hope that it will be useful, but
43 * WITHOUT ANY WARRANTY; without even the implied warranty of
44 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
45 * NON INFRINGEMENT. See the GNU General Public License for more
50 #include <linux/kernel.h>
51 #include <linux/module.h>
52 #include <linux/pci.h>
53 #include <linux/semaphore.h>
54 #include <linux/irqdomain.h>
55 #include <asm/irqdomain.h>
57 #include <linux/msi.h>
58 #include <linux/hyperv.h>
59 #include <asm/mshyperv.h>
62 * Protocol versions. The low word is the minor version, the high word the
66 #define PCI_MAKE_VERSION(major, minor) ((u32)(((major) << 16) | (major)))
67 #define PCI_MAJOR_VERSION(version) ((u32)(version) >> 16)
68 #define PCI_MINOR_VERSION(version) ((u32)(version) & 0xff)
71 PCI_PROTOCOL_VERSION_1_1
= PCI_MAKE_VERSION(1, 1),
72 PCI_PROTOCOL_VERSION_CURRENT
= PCI_PROTOCOL_VERSION_1_1
75 #define PCI_CONFIG_MMIO_LENGTH 0x2000
76 #define CFG_PAGE_OFFSET 0x1000
77 #define CFG_PAGE_SIZE (PCI_CONFIG_MMIO_LENGTH - CFG_PAGE_OFFSET)
79 #define MAX_SUPPORTED_MSI_MESSAGES 0x400
85 enum pci_message_type
{
89 PCI_MESSAGE_BASE
= 0x42490000,
90 PCI_BUS_RELATIONS
= PCI_MESSAGE_BASE
+ 0,
91 PCI_QUERY_BUS_RELATIONS
= PCI_MESSAGE_BASE
+ 1,
92 PCI_POWER_STATE_CHANGE
= PCI_MESSAGE_BASE
+ 4,
93 PCI_QUERY_RESOURCE_REQUIREMENTS
= PCI_MESSAGE_BASE
+ 5,
94 PCI_QUERY_RESOURCE_RESOURCES
= PCI_MESSAGE_BASE
+ 6,
95 PCI_BUS_D0ENTRY
= PCI_MESSAGE_BASE
+ 7,
96 PCI_BUS_D0EXIT
= PCI_MESSAGE_BASE
+ 8,
97 PCI_READ_BLOCK
= PCI_MESSAGE_BASE
+ 9,
98 PCI_WRITE_BLOCK
= PCI_MESSAGE_BASE
+ 0xA,
99 PCI_EJECT
= PCI_MESSAGE_BASE
+ 0xB,
100 PCI_QUERY_STOP
= PCI_MESSAGE_BASE
+ 0xC,
101 PCI_REENABLE
= PCI_MESSAGE_BASE
+ 0xD,
102 PCI_QUERY_STOP_FAILED
= PCI_MESSAGE_BASE
+ 0xE,
103 PCI_EJECTION_COMPLETE
= PCI_MESSAGE_BASE
+ 0xF,
104 PCI_RESOURCES_ASSIGNED
= PCI_MESSAGE_BASE
+ 0x10,
105 PCI_RESOURCES_RELEASED
= PCI_MESSAGE_BASE
+ 0x11,
106 PCI_INVALIDATE_BLOCK
= PCI_MESSAGE_BASE
+ 0x12,
107 PCI_QUERY_PROTOCOL_VERSION
= PCI_MESSAGE_BASE
+ 0x13,
108 PCI_CREATE_INTERRUPT_MESSAGE
= PCI_MESSAGE_BASE
+ 0x14,
109 PCI_DELETE_INTERRUPT_MESSAGE
= PCI_MESSAGE_BASE
+ 0x15,
114 * Structures defining the virtual PCI Express protocol.
126 * Function numbers are 8-bits wide on Express, as interpreted through ARI,
127 * which is all this driver does. This representation is the one used in
128 * Windows, which is what is expected when sending this back and forth with
129 * the Hyper-V parent partition.
131 union win_slot_encoding
{
140 * Pretty much as defined in the PCI Specifications.
142 struct pci_function_description
{
143 u16 v_id
; /* vendor ID */
144 u16 d_id
; /* device ID */
150 union win_slot_encoding win_slot
;
151 u32 ser
; /* serial number */
157 * @delivery_mode: As defined in Intel's Programmer's
158 * Reference Manual, Volume 3, Chapter 8.
159 * @vector_count: Number of contiguous entries in the
160 * Interrupt Descriptor Table that are
161 * occupied by this Message-Signaled
162 * Interrupt. For "MSI", as first defined
163 * in PCI 2.2, this can be between 1 and
164 * 32. For "MSI-X," as first defined in PCI
165 * 3.0, this must be 1, as each MSI-X table
166 * entry would have its own descriptor.
167 * @reserved: Empty space
168 * @cpu_mask: All the target virtual processors.
179 * struct tran_int_desc
180 * @reserved: unused, padding
181 * @vector_count: same as in hv_msi_desc
182 * @data: This is the "data payload" value that is
183 * written by the device when it generates
184 * a message-signaled interrupt, either MSI
186 * @address: This is the address to which the data
187 * payload is written on interrupt
190 struct tran_int_desc
{
198 * A generic message format for virtual PCI.
199 * Specific message formats are defined later in the file.
206 struct pci_child_message
{
207 struct pci_message message_type
;
208 union win_slot_encoding wslot
;
211 struct pci_incoming_message
{
212 struct vmpacket_descriptor hdr
;
213 struct pci_message message_type
;
216 struct pci_response
{
217 struct vmpacket_descriptor hdr
;
218 s32 status
; /* negative values are failures */
222 void (*completion_func
)(void *context
, struct pci_response
*resp
,
223 int resp_packet_size
);
226 struct pci_message message
[0];
230 * Specific message types supporting the PCI protocol.
234 * Version negotiation message. Sent from the guest to the host.
235 * The guest is free to try different versions until the host
236 * accepts the version.
238 * pci_version: The protocol version requested.
239 * is_last_attempt: If TRUE, this is the last version guest will request.
240 * reservedz: Reserved field, set to zero.
243 struct pci_version_request
{
244 struct pci_message message_type
;
245 enum pci_message_type protocol_version
;
249 * Bus D0 Entry. This is sent from the guest to the host when the virtual
250 * bus (PCI Express port) is ready for action.
253 struct pci_bus_d0_entry
{
254 struct pci_message message_type
;
259 struct pci_bus_relations
{
260 struct pci_incoming_message incoming
;
262 struct pci_function_description func
[1];
265 struct pci_q_res_req_response
{
266 struct vmpacket_descriptor hdr
;
267 s32 status
; /* negative values are failures */
271 struct pci_set_power
{
272 struct pci_message message_type
;
273 union win_slot_encoding wslot
;
274 u32 power_state
; /* In Windows terms */
278 struct pci_set_power_response
{
279 struct vmpacket_descriptor hdr
;
280 s32 status
; /* negative values are failures */
281 union win_slot_encoding wslot
;
282 u32 resultant_state
; /* In Windows terms */
286 struct pci_resources_assigned
{
287 struct pci_message message_type
;
288 union win_slot_encoding wslot
;
289 u8 memory_range
[0x14][6]; /* not used here */
294 struct pci_create_interrupt
{
295 struct pci_message message_type
;
296 union win_slot_encoding wslot
;
297 struct hv_msi_desc int_desc
;
300 struct pci_create_int_response
{
301 struct pci_response response
;
303 struct tran_int_desc int_desc
;
306 struct pci_delete_interrupt
{
307 struct pci_message message_type
;
308 union win_slot_encoding wslot
;
309 struct tran_int_desc int_desc
;
312 struct pci_dev_incoming
{
313 struct pci_incoming_message incoming
;
314 union win_slot_encoding wslot
;
317 struct pci_eject_response
{
318 struct pci_message message_type
;
319 union win_slot_encoding wslot
;
323 static int pci_ring_size
= (4 * PAGE_SIZE
);
326 * Definitions or interrupt steering hypercall.
328 #define HV_PARTITION_ID_SELF ((u64)-1)
329 #define HVCALL_RETARGET_INTERRUPT 0x7e
331 struct retarget_msi_interrupt
{
332 u64 partition_id
; /* use "self" */
334 u32 source
; /* 1 for MSI(-X) */
345 * Driver specific state.
348 enum hv_pcibus_state
{
355 struct hv_pcibus_device
{
356 struct pci_sysdata sysdata
;
357 enum hv_pcibus_state state
;
358 atomic_t remove_lock
;
359 struct hv_device
*hdev
;
360 resource_size_t low_mmio_space
;
361 resource_size_t high_mmio_space
;
362 struct resource
*mem_config
;
363 struct resource
*low_mmio_res
;
364 struct resource
*high_mmio_res
;
365 struct completion
*survey_event
;
366 struct completion remove_event
;
367 struct pci_bus
*pci_bus
;
368 spinlock_t config_lock
; /* Avoid two threads writing index page */
369 spinlock_t device_list_lock
; /* Protect lists below */
370 void __iomem
*cfg_addr
;
372 struct semaphore enum_sem
;
373 struct list_head resources_for_children
;
375 struct list_head children
;
376 struct list_head dr_list
;
377 struct work_struct wrk
;
379 struct msi_domain_info msi_info
;
380 struct msi_controller msi_chip
;
381 struct irq_domain
*irq_domain
;
385 * Tracks "Device Relations" messages from the host, which must be both
386 * processed in order and deferred so that they don't run in the context
387 * of the incoming packet callback.
390 struct work_struct wrk
;
391 struct hv_pcibus_device
*bus
;
395 struct list_head list_entry
;
397 struct pci_function_description func
[1];
400 enum hv_pcichild_state
{
401 hv_pcichild_init
= 0,
402 hv_pcichild_requirements
,
403 hv_pcichild_resourced
,
404 hv_pcichild_ejecting
,
408 enum hv_pcidev_ref_reason
{
409 hv_pcidev_ref_invalid
= 0,
410 hv_pcidev_ref_initial
,
411 hv_pcidev_ref_by_slot
,
412 hv_pcidev_ref_packet
,
414 hv_pcidev_ref_childlist
,
420 /* List protected by pci_rescan_remove_lock */
421 struct list_head list_entry
;
423 enum hv_pcichild_state state
;
424 struct pci_function_description desc
;
425 bool reported_missing
;
426 struct hv_pcibus_device
*hbus
;
427 struct work_struct wrk
;
430 * What would be observed if one wrote 0xFFFFFFFF to a BAR and then
431 * read it back, for each of the BAR offsets within config space.
436 struct hv_pci_compl
{
437 struct completion host_event
;
438 s32 completion_status
;
442 * hv_pci_generic_compl() - Invoked for a completion packet
443 * @context: Set up by the sender of the packet.
444 * @resp: The response packet
445 * @resp_packet_size: Size in bytes of the packet
447 * This function is used to trigger an event and report status
448 * for any message for which the completion packet contains a
449 * status and nothing else.
453 hv_pci_generic_compl(void *context
, struct pci_response
*resp
,
454 int resp_packet_size
)
456 struct hv_pci_compl
*comp_pkt
= context
;
458 if (resp_packet_size
>= offsetofend(struct pci_response
, status
))
459 comp_pkt
->completion_status
= resp
->status
;
460 complete(&comp_pkt
->host_event
);
463 static struct hv_pci_dev
*get_pcichild_wslot(struct hv_pcibus_device
*hbus
,
465 static void get_pcichild(struct hv_pci_dev
*hv_pcidev
,
466 enum hv_pcidev_ref_reason reason
);
467 static void put_pcichild(struct hv_pci_dev
*hv_pcidev
,
468 enum hv_pcidev_ref_reason reason
);
470 static void get_hvpcibus(struct hv_pcibus_device
*hv_pcibus
);
471 static void put_hvpcibus(struct hv_pcibus_device
*hv_pcibus
);
474 * devfn_to_wslot() - Convert from Linux PCI slot to Windows
475 * @devfn: The Linux representation of PCI slot
477 * Windows uses a slightly different representation of PCI slot.
479 * Return: The Windows representation
481 static u32
devfn_to_wslot(int devfn
)
483 union win_slot_encoding wslot
;
486 wslot
.bits
.func
= PCI_SLOT(devfn
) | (PCI_FUNC(devfn
) << 5);
492 * wslot_to_devfn() - Convert from Windows PCI slot to Linux
493 * @wslot: The Windows representation of PCI slot
495 * Windows uses a slightly different representation of PCI slot.
497 * Return: The Linux representation
499 static int wslot_to_devfn(u32 wslot
)
501 union win_slot_encoding slot_no
;
503 slot_no
.slot
= wslot
;
504 return PCI_DEVFN(0, slot_no
.bits
.func
);
508 * PCI Configuration Space for these root PCI buses is implemented as a pair
509 * of pages in memory-mapped I/O space. Writing to the first page chooses
510 * the PCI function being written or read. Once the first page has been
511 * written to, the following page maps in the entire configuration space of
516 * _hv_pcifront_read_config() - Internal PCI config read
517 * @hpdev: The PCI driver's representation of the device
518 * @where: Offset within config space
519 * @size: Size of the transfer
520 * @val: Pointer to the buffer receiving the data
522 static void _hv_pcifront_read_config(struct hv_pci_dev
*hpdev
, int where
,
526 void __iomem
*addr
= hpdev
->hbus
->cfg_addr
+ CFG_PAGE_OFFSET
+ where
;
529 * If the attempt is to read the IDs or the ROM BAR, simulate that.
531 if (where
+ size
<= PCI_COMMAND
) {
532 memcpy(val
, ((u8
*)&hpdev
->desc
.v_id
) + where
, size
);
533 } else if (where
>= PCI_CLASS_REVISION
&& where
+ size
<=
534 PCI_CACHE_LINE_SIZE
) {
535 memcpy(val
, ((u8
*)&hpdev
->desc
.rev
) + where
-
536 PCI_CLASS_REVISION
, size
);
537 } else if (where
>= PCI_SUBSYSTEM_VENDOR_ID
&& where
+ size
<=
539 memcpy(val
, (u8
*)&hpdev
->desc
.subsystem_id
+ where
-
540 PCI_SUBSYSTEM_VENDOR_ID
, size
);
541 } else if (where
>= PCI_ROM_ADDRESS
&& where
+ size
<=
542 PCI_CAPABILITY_LIST
) {
543 /* ROM BARs are unimplemented */
545 } else if (where
>= PCI_INTERRUPT_LINE
&& where
+ size
<=
548 * Interrupt Line and Interrupt PIN are hard-wired to zero
549 * because this front-end only supports message-signaled
553 } else if (where
+ size
<= CFG_PAGE_SIZE
) {
554 spin_lock_irqsave(&hpdev
->hbus
->config_lock
, flags
);
555 /* Choose the function to be read. (See comment above) */
556 writel(hpdev
->desc
.win_slot
.slot
, hpdev
->hbus
->cfg_addr
);
557 /* Make sure the function was chosen before we start reading. */
559 /* Read from that function's config space. */
572 * Make sure the write was done before we release the spinlock
573 * allowing consecutive reads/writes.
576 spin_unlock_irqrestore(&hpdev
->hbus
->config_lock
, flags
);
578 dev_err(&hpdev
->hbus
->hdev
->device
,
579 "Attempt to read beyond a function's config space.\n");
584 * _hv_pcifront_write_config() - Internal PCI config write
585 * @hpdev: The PCI driver's representation of the device
586 * @where: Offset within config space
587 * @size: Size of the transfer
588 * @val: The data being transferred
590 static void _hv_pcifront_write_config(struct hv_pci_dev
*hpdev
, int where
,
594 void __iomem
*addr
= hpdev
->hbus
->cfg_addr
+ CFG_PAGE_OFFSET
+ where
;
596 if (where
>= PCI_SUBSYSTEM_VENDOR_ID
&&
597 where
+ size
<= PCI_CAPABILITY_LIST
) {
598 /* SSIDs and ROM BARs are read-only */
599 } else if (where
>= PCI_COMMAND
&& where
+ size
<= CFG_PAGE_SIZE
) {
600 spin_lock_irqsave(&hpdev
->hbus
->config_lock
, flags
);
601 /* Choose the function to be written. (See comment above) */
602 writel(hpdev
->desc
.win_slot
.slot
, hpdev
->hbus
->cfg_addr
);
603 /* Make sure the function was chosen before we start writing. */
605 /* Write to that function's config space. */
618 * Make sure the write was done before we release the spinlock
619 * allowing consecutive reads/writes.
622 spin_unlock_irqrestore(&hpdev
->hbus
->config_lock
, flags
);
624 dev_err(&hpdev
->hbus
->hdev
->device
,
625 "Attempt to write beyond a function's config space.\n");
630 * hv_pcifront_read_config() - Read configuration space
631 * @bus: PCI Bus structure
632 * @devfn: Device/function
633 * @where: Offset from base
634 * @size: Byte/word/dword
635 * @val: Value to be read
637 * Return: PCIBIOS_SUCCESSFUL on success
638 * PCIBIOS_DEVICE_NOT_FOUND on failure
640 static int hv_pcifront_read_config(struct pci_bus
*bus
, unsigned int devfn
,
641 int where
, int size
, u32
*val
)
643 struct hv_pcibus_device
*hbus
=
644 container_of(bus
->sysdata
, struct hv_pcibus_device
, sysdata
);
645 struct hv_pci_dev
*hpdev
;
647 hpdev
= get_pcichild_wslot(hbus
, devfn_to_wslot(devfn
));
649 return PCIBIOS_DEVICE_NOT_FOUND
;
651 _hv_pcifront_read_config(hpdev
, where
, size
, val
);
653 put_pcichild(hpdev
, hv_pcidev_ref_by_slot
);
654 return PCIBIOS_SUCCESSFUL
;
658 * hv_pcifront_write_config() - Write configuration space
659 * @bus: PCI Bus structure
660 * @devfn: Device/function
661 * @where: Offset from base
662 * @size: Byte/word/dword
663 * @val: Value to be written to device
665 * Return: PCIBIOS_SUCCESSFUL on success
666 * PCIBIOS_DEVICE_NOT_FOUND on failure
668 static int hv_pcifront_write_config(struct pci_bus
*bus
, unsigned int devfn
,
669 int where
, int size
, u32 val
)
671 struct hv_pcibus_device
*hbus
=
672 container_of(bus
->sysdata
, struct hv_pcibus_device
, sysdata
);
673 struct hv_pci_dev
*hpdev
;
675 hpdev
= get_pcichild_wslot(hbus
, devfn_to_wslot(devfn
));
677 return PCIBIOS_DEVICE_NOT_FOUND
;
679 _hv_pcifront_write_config(hpdev
, where
, size
, val
);
681 put_pcichild(hpdev
, hv_pcidev_ref_by_slot
);
682 return PCIBIOS_SUCCESSFUL
;
685 /* PCIe operations */
686 static struct pci_ops hv_pcifront_ops
= {
687 .read
= hv_pcifront_read_config
,
688 .write
= hv_pcifront_write_config
,
691 /* Interrupt management hooks */
692 static void hv_int_desc_free(struct hv_pci_dev
*hpdev
,
693 struct tran_int_desc
*int_desc
)
695 struct pci_delete_interrupt
*int_pkt
;
697 struct pci_packet pkt
;
698 u8 buffer
[sizeof(struct pci_delete_interrupt
)];
701 memset(&ctxt
, 0, sizeof(ctxt
));
702 int_pkt
= (struct pci_delete_interrupt
*)&ctxt
.pkt
.message
;
703 int_pkt
->message_type
.type
=
704 PCI_DELETE_INTERRUPT_MESSAGE
;
705 int_pkt
->wslot
.slot
= hpdev
->desc
.win_slot
.slot
;
706 int_pkt
->int_desc
= *int_desc
;
707 vmbus_sendpacket(hpdev
->hbus
->hdev
->channel
, int_pkt
, sizeof(*int_pkt
),
708 (unsigned long)&ctxt
.pkt
, VM_PKT_DATA_INBAND
, 0);
713 * hv_msi_free() - Free the MSI.
714 * @domain: The interrupt domain pointer
715 * @info: Extra MSI-related context
716 * @irq: Identifies the IRQ.
718 * The Hyper-V parent partition and hypervisor are tracking the
719 * messages that are in use, keeping the interrupt redirection
720 * table up to date. This callback sends a message that frees
721 * the IRT entry and related tracking nonsense.
723 static void hv_msi_free(struct irq_domain
*domain
, struct msi_domain_info
*info
,
726 struct hv_pcibus_device
*hbus
;
727 struct hv_pci_dev
*hpdev
;
728 struct pci_dev
*pdev
;
729 struct tran_int_desc
*int_desc
;
730 struct irq_data
*irq_data
= irq_domain_get_irq_data(domain
, irq
);
731 struct msi_desc
*msi
= irq_data_get_msi_desc(irq_data
);
733 pdev
= msi_desc_to_pci_dev(msi
);
735 int_desc
= irq_data_get_irq_chip_data(irq_data
);
739 irq_data
->chip_data
= NULL
;
740 hpdev
= get_pcichild_wslot(hbus
, devfn_to_wslot(pdev
->devfn
));
746 hv_int_desc_free(hpdev
, int_desc
);
747 put_pcichild(hpdev
, hv_pcidev_ref_by_slot
);
750 static int hv_set_affinity(struct irq_data
*data
, const struct cpumask
*dest
,
753 struct irq_data
*parent
= data
->parent_data
;
755 return parent
->chip
->irq_set_affinity(parent
, dest
, force
);
758 void hv_irq_mask(struct irq_data
*data
)
760 pci_msi_mask_irq(data
);
764 * hv_irq_unmask() - "Unmask" the IRQ by setting its current
766 * @data: Describes the IRQ
768 * Build new a destination for the MSI and make a hypercall to
769 * update the Interrupt Redirection Table. "Device Logical ID"
770 * is built out of this PCI bus's instance GUID and the function
771 * number of the device.
773 void hv_irq_unmask(struct irq_data
*data
)
775 struct msi_desc
*msi_desc
= irq_data_get_msi_desc(data
);
776 struct irq_cfg
*cfg
= irqd_cfg(data
);
777 struct retarget_msi_interrupt params
;
778 struct hv_pcibus_device
*hbus
;
779 struct cpumask
*dest
;
780 struct pci_bus
*pbus
;
781 struct pci_dev
*pdev
;
784 dest
= irq_data_get_affinity_mask(data
);
785 pdev
= msi_desc_to_pci_dev(msi_desc
);
787 hbus
= container_of(pbus
->sysdata
, struct hv_pcibus_device
, sysdata
);
789 memset(¶ms
, 0, sizeof(params
));
790 params
.partition_id
= HV_PARTITION_ID_SELF
;
791 params
.source
= 1; /* MSI(-X) */
792 params
.address
= msi_desc
->msg
.address_lo
;
793 params
.data
= msi_desc
->msg
.data
;
794 params
.device_id
= (hbus
->hdev
->dev_instance
.b
[5] << 24) |
795 (hbus
->hdev
->dev_instance
.b
[4] << 16) |
796 (hbus
->hdev
->dev_instance
.b
[7] << 8) |
797 (hbus
->hdev
->dev_instance
.b
[6] & 0xf8) |
798 PCI_FUNC(pdev
->devfn
);
799 params
.vector
= cfg
->vector
;
801 for_each_cpu_and(cpu
, dest
, cpu_online_mask
)
802 params
.vp_mask
|= (1ULL << vmbus_cpu_number_to_vp_number(cpu
));
804 hv_do_hypercall(HVCALL_RETARGET_INTERRUPT
, ¶ms
, NULL
);
806 pci_msi_unmask_irq(data
);
809 struct compose_comp_ctxt
{
810 struct hv_pci_compl comp_pkt
;
811 struct tran_int_desc int_desc
;
814 static void hv_pci_compose_compl(void *context
, struct pci_response
*resp
,
815 int resp_packet_size
)
817 struct compose_comp_ctxt
*comp_pkt
= context
;
818 struct pci_create_int_response
*int_resp
=
819 (struct pci_create_int_response
*)resp
;
821 comp_pkt
->comp_pkt
.completion_status
= resp
->status
;
822 comp_pkt
->int_desc
= int_resp
->int_desc
;
823 complete(&comp_pkt
->comp_pkt
.host_event
);
827 * hv_compose_msi_msg() - Supplies a valid MSI address/data
828 * @data: Everything about this MSI
829 * @msg: Buffer that is filled in by this function
831 * This function unpacks the IRQ looking for target CPU set, IDT
832 * vector and mode and sends a message to the parent partition
833 * asking for a mapping for that tuple in this partition. The
834 * response supplies a data value and address to which that data
835 * should be written to trigger that interrupt.
837 static void hv_compose_msi_msg(struct irq_data
*data
, struct msi_msg
*msg
)
839 struct irq_cfg
*cfg
= irqd_cfg(data
);
840 struct hv_pcibus_device
*hbus
;
841 struct hv_pci_dev
*hpdev
;
842 struct pci_bus
*pbus
;
843 struct pci_dev
*pdev
;
844 struct pci_create_interrupt
*int_pkt
;
845 struct compose_comp_ctxt comp
;
846 struct tran_int_desc
*int_desc
;
847 struct cpumask
*affinity
;
849 struct pci_packet pkt
;
850 u8 buffer
[sizeof(struct pci_create_interrupt
)];
855 pdev
= msi_desc_to_pci_dev(irq_data_get_msi_desc(data
));
857 hbus
= container_of(pbus
->sysdata
, struct hv_pcibus_device
, sysdata
);
858 hpdev
= get_pcichild_wslot(hbus
, devfn_to_wslot(pdev
->devfn
));
860 goto return_null_message
;
862 /* Free any previous message that might have already been composed. */
863 if (data
->chip_data
) {
864 int_desc
= data
->chip_data
;
865 data
->chip_data
= NULL
;
866 hv_int_desc_free(hpdev
, int_desc
);
869 int_desc
= kzalloc(sizeof(*int_desc
), GFP_KERNEL
);
873 memset(&ctxt
, 0, sizeof(ctxt
));
874 init_completion(&comp
.comp_pkt
.host_event
);
875 ctxt
.pkt
.completion_func
= hv_pci_compose_compl
;
876 ctxt
.pkt
.compl_ctxt
= &comp
;
877 int_pkt
= (struct pci_create_interrupt
*)&ctxt
.pkt
.message
;
878 int_pkt
->message_type
.type
= PCI_CREATE_INTERRUPT_MESSAGE
;
879 int_pkt
->wslot
.slot
= hpdev
->desc
.win_slot
.slot
;
880 int_pkt
->int_desc
.vector
= cfg
->vector
;
881 int_pkt
->int_desc
.vector_count
= 1;
882 int_pkt
->int_desc
.delivery_mode
=
883 (apic
->irq_delivery_mode
== dest_LowestPrio
) ? 1 : 0;
886 * This bit doesn't have to work on machines with more than 64
887 * processors because Hyper-V only supports 64 in a guest.
889 affinity
= irq_data_get_affinity_mask(data
);
890 for_each_cpu_and(cpu
, affinity
, cpu_online_mask
) {
891 int_pkt
->int_desc
.cpu_mask
|=
892 (1ULL << vmbus_cpu_number_to_vp_number(cpu
));
895 ret
= vmbus_sendpacket(hpdev
->hbus
->hdev
->channel
, int_pkt
,
896 sizeof(*int_pkt
), (unsigned long)&ctxt
.pkt
,
898 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED
);
900 wait_for_completion(&comp
.comp_pkt
.host_event
);
902 if (comp
.comp_pkt
.completion_status
< 0) {
903 dev_err(&hbus
->hdev
->device
,
904 "Request for interrupt failed: 0x%x",
905 comp
.comp_pkt
.completion_status
);
910 * Record the assignment so that this can be unwound later. Using
911 * irq_set_chip_data() here would be appropriate, but the lock it takes
914 *int_desc
= comp
.int_desc
;
915 data
->chip_data
= int_desc
;
917 /* Pass up the result. */
918 msg
->address_hi
= comp
.int_desc
.address
>> 32;
919 msg
->address_lo
= comp
.int_desc
.address
& 0xffffffff;
920 msg
->data
= comp
.int_desc
.data
;
922 put_pcichild(hpdev
, hv_pcidev_ref_by_slot
);
928 put_pcichild(hpdev
, hv_pcidev_ref_by_slot
);
935 /* HW Interrupt Chip Descriptor */
936 static struct irq_chip hv_msi_irq_chip
= {
937 .name
= "Hyper-V PCIe MSI",
938 .irq_compose_msi_msg
= hv_compose_msi_msg
,
939 .irq_set_affinity
= hv_set_affinity
,
940 .irq_ack
= irq_chip_ack_parent
,
941 .irq_mask
= hv_irq_mask
,
942 .irq_unmask
= hv_irq_unmask
,
945 static irq_hw_number_t
hv_msi_domain_ops_get_hwirq(struct msi_domain_info
*info
,
946 msi_alloc_info_t
*arg
)
948 return arg
->msi_hwirq
;
951 static struct msi_domain_ops hv_msi_ops
= {
952 .get_hwirq
= hv_msi_domain_ops_get_hwirq
,
953 .msi_prepare
= pci_msi_prepare
,
954 .set_desc
= pci_msi_set_desc
,
955 .msi_free
= hv_msi_free
,
959 * hv_pcie_init_irq_domain() - Initialize IRQ domain
960 * @hbus: The root PCI bus
962 * This function creates an IRQ domain which will be used for
963 * interrupts from devices that have been passed through. These
964 * devices only support MSI and MSI-X, not line-based interrupts
965 * or simulations of line-based interrupts through PCIe's
966 * fabric-layer messages. Because interrupts are remapped, we
967 * can support multi-message MSI here.
969 * Return: '0' on success and error value on failure
971 static int hv_pcie_init_irq_domain(struct hv_pcibus_device
*hbus
)
973 hbus
->msi_info
.chip
= &hv_msi_irq_chip
;
974 hbus
->msi_info
.ops
= &hv_msi_ops
;
975 hbus
->msi_info
.flags
= (MSI_FLAG_USE_DEF_DOM_OPS
|
976 MSI_FLAG_USE_DEF_CHIP_OPS
| MSI_FLAG_MULTI_PCI_MSI
|
978 hbus
->msi_info
.handler
= handle_edge_irq
;
979 hbus
->msi_info
.handler_name
= "edge";
980 hbus
->msi_info
.data
= hbus
;
981 hbus
->irq_domain
= pci_msi_create_irq_domain(hbus
->sysdata
.fwnode
,
984 if (!hbus
->irq_domain
) {
985 dev_err(&hbus
->hdev
->device
,
986 "Failed to build an MSI IRQ domain\n");
994 * get_bar_size() - Get the address space consumed by a BAR
995 * @bar_val: Value that a BAR returned after -1 was written
998 * This function returns the size of the BAR, rounded up to 1
999 * page. It has to be rounded up because the hypervisor's page
1000 * table entry that maps the BAR into the VM can't specify an
1001 * offset within a page. The invariant is that the hypervisor
1002 * must place any BARs of smaller than page length at the
1003 * beginning of a page.
1005 * Return: Size in bytes of the consumed MMIO space.
1007 static u64
get_bar_size(u64 bar_val
)
1009 return round_up((1 + ~(bar_val
& PCI_BASE_ADDRESS_MEM_MASK
)),
1014 * survey_child_resources() - Total all MMIO requirements
1015 * @hbus: Root PCI bus, as understood by this driver
1017 static void survey_child_resources(struct hv_pcibus_device
*hbus
)
1019 struct list_head
*iter
;
1020 struct hv_pci_dev
*hpdev
;
1021 resource_size_t bar_size
= 0;
1022 unsigned long flags
;
1023 struct completion
*event
;
1027 /* If nobody is waiting on the answer, don't compute it. */
1028 event
= xchg(&hbus
->survey_event
, NULL
);
1032 /* If the answer has already been computed, go with it. */
1033 if (hbus
->low_mmio_space
|| hbus
->high_mmio_space
) {
1038 spin_lock_irqsave(&hbus
->device_list_lock
, flags
);
1041 * Due to an interesting quirk of the PCI spec, all memory regions
1042 * for a child device are a power of 2 in size and aligned in memory,
1043 * so it's sufficient to just add them up without tracking alignment.
1045 list_for_each(iter
, &hbus
->children
) {
1046 hpdev
= container_of(iter
, struct hv_pci_dev
, list_entry
);
1047 for (i
= 0; i
< 6; i
++) {
1048 if (hpdev
->probed_bar
[i
] & PCI_BASE_ADDRESS_SPACE_IO
)
1049 dev_err(&hbus
->hdev
->device
,
1050 "There's an I/O BAR in this list!\n");
1052 if (hpdev
->probed_bar
[i
] != 0) {
1054 * A probed BAR has all the upper bits set that
1058 bar_val
= hpdev
->probed_bar
[i
];
1059 if (bar_val
& PCI_BASE_ADDRESS_MEM_TYPE_64
)
1061 ((u64
)hpdev
->probed_bar
[++i
] << 32);
1063 bar_val
|= 0xffffffff00000000ULL
;
1065 bar_size
= get_bar_size(bar_val
);
1067 if (bar_val
& PCI_BASE_ADDRESS_MEM_TYPE_64
)
1068 hbus
->high_mmio_space
+= bar_size
;
1070 hbus
->low_mmio_space
+= bar_size
;
1075 spin_unlock_irqrestore(&hbus
->device_list_lock
, flags
);
1080 * prepopulate_bars() - Fill in BARs with defaults
1081 * @hbus: Root PCI bus, as understood by this driver
1083 * The core PCI driver code seems much, much happier if the BARs
1084 * for a device have values upon first scan. So fill them in.
1085 * The algorithm below works down from large sizes to small,
1086 * attempting to pack the assignments optimally. The assumption,
1087 * enforced in other parts of the code, is that the beginning of
1088 * the memory-mapped I/O space will be aligned on the largest
1091 static void prepopulate_bars(struct hv_pcibus_device
*hbus
)
1093 resource_size_t high_size
= 0;
1094 resource_size_t low_size
= 0;
1095 resource_size_t high_base
= 0;
1096 resource_size_t low_base
= 0;
1097 resource_size_t bar_size
;
1098 struct hv_pci_dev
*hpdev
;
1099 struct list_head
*iter
;
1100 unsigned long flags
;
1106 if (hbus
->low_mmio_space
) {
1107 low_size
= 1ULL << (63 - __builtin_clzll(hbus
->low_mmio_space
));
1108 low_base
= hbus
->low_mmio_res
->start
;
1111 if (hbus
->high_mmio_space
) {
1113 (63 - __builtin_clzll(hbus
->high_mmio_space
));
1114 high_base
= hbus
->high_mmio_res
->start
;
1117 spin_lock_irqsave(&hbus
->device_list_lock
, flags
);
1119 /* Pick addresses for the BARs. */
1121 list_for_each(iter
, &hbus
->children
) {
1122 hpdev
= container_of(iter
, struct hv_pci_dev
,
1124 for (i
= 0; i
< 6; i
++) {
1125 bar_val
= hpdev
->probed_bar
[i
];
1128 high
= bar_val
& PCI_BASE_ADDRESS_MEM_TYPE_64
;
1131 ((u64
)hpdev
->probed_bar
[i
+ 1]
1134 bar_val
|= 0xffffffffULL
<< 32;
1136 bar_size
= get_bar_size(bar_val
);
1138 if (high_size
!= bar_size
) {
1142 _hv_pcifront_write_config(hpdev
,
1143 PCI_BASE_ADDRESS_0
+ (4 * i
),
1145 (u32
)(high_base
& 0xffffff00));
1147 _hv_pcifront_write_config(hpdev
,
1148 PCI_BASE_ADDRESS_0
+ (4 * i
),
1149 4, (u32
)(high_base
>> 32));
1150 high_base
+= bar_size
;
1152 if (low_size
!= bar_size
)
1154 _hv_pcifront_write_config(hpdev
,
1155 PCI_BASE_ADDRESS_0
+ (4 * i
),
1157 (u32
)(low_base
& 0xffffff00));
1158 low_base
+= bar_size
;
1161 if (high_size
<= 1 && low_size
<= 1) {
1162 /* Set the memory enable bit. */
1163 _hv_pcifront_read_config(hpdev
, PCI_COMMAND
, 2,
1165 command
|= PCI_COMMAND_MEMORY
;
1166 _hv_pcifront_write_config(hpdev
, PCI_COMMAND
, 2,
1174 } while (high_size
|| low_size
);
1176 spin_unlock_irqrestore(&hbus
->device_list_lock
, flags
);
1180 * create_root_hv_pci_bus() - Expose a new root PCI bus
1181 * @hbus: Root PCI bus, as understood by this driver
1183 * Return: 0 on success, -errno on failure
1185 static int create_root_hv_pci_bus(struct hv_pcibus_device
*hbus
)
1187 /* Register the device */
1188 hbus
->pci_bus
= pci_create_root_bus(&hbus
->hdev
->device
,
1189 0, /* bus number is always zero */
1192 &hbus
->resources_for_children
);
1196 hbus
->pci_bus
->msi
= &hbus
->msi_chip
;
1197 hbus
->pci_bus
->msi
->dev
= &hbus
->hdev
->device
;
1199 pci_scan_child_bus(hbus
->pci_bus
);
1200 pci_bus_assign_resources(hbus
->pci_bus
);
1201 pci_bus_add_devices(hbus
->pci_bus
);
1202 hbus
->state
= hv_pcibus_installed
;
1206 struct q_res_req_compl
{
1207 struct completion host_event
;
1208 struct hv_pci_dev
*hpdev
;
1212 * q_resource_requirements() - Query Resource Requirements
1213 * @context: The completion context.
1214 * @resp: The response that came from the host.
1215 * @resp_packet_size: The size in bytes of resp.
1217 * This function is invoked on completion of a Query Resource
1218 * Requirements packet.
1220 static void q_resource_requirements(void *context
, struct pci_response
*resp
,
1221 int resp_packet_size
)
1223 struct q_res_req_compl
*completion
= context
;
1224 struct pci_q_res_req_response
*q_res_req
=
1225 (struct pci_q_res_req_response
*)resp
;
1228 if (resp
->status
< 0) {
1229 dev_err(&completion
->hpdev
->hbus
->hdev
->device
,
1230 "query resource requirements failed: %x\n",
1233 for (i
= 0; i
< 6; i
++) {
1234 completion
->hpdev
->probed_bar
[i
] =
1235 q_res_req
->probed_bar
[i
];
1239 complete(&completion
->host_event
);
1242 static void get_pcichild(struct hv_pci_dev
*hpdev
,
1243 enum hv_pcidev_ref_reason reason
)
1245 atomic_inc(&hpdev
->refs
);
1248 static void put_pcichild(struct hv_pci_dev
*hpdev
,
1249 enum hv_pcidev_ref_reason reason
)
1251 if (atomic_dec_and_test(&hpdev
->refs
))
1256 * new_pcichild_device() - Create a new child device
1257 * @hbus: The internal struct tracking this root PCI bus.
1258 * @desc: The information supplied so far from the host
1261 * This function creates the tracking structure for a new child
1262 * device and kicks off the process of figuring out what it is.
1264 * Return: Pointer to the new tracking struct
1266 static struct hv_pci_dev
*new_pcichild_device(struct hv_pcibus_device
*hbus
,
1267 struct pci_function_description
*desc
)
1269 struct hv_pci_dev
*hpdev
;
1270 struct pci_child_message
*res_req
;
1271 struct q_res_req_compl comp_pkt
;
1273 struct pci_packet init_packet
;
1276 unsigned long flags
;
1279 hpdev
= kzalloc(sizeof(*hpdev
), GFP_ATOMIC
);
1285 memset(&pkt
, 0, sizeof(pkt
));
1286 init_completion(&comp_pkt
.host_event
);
1287 comp_pkt
.hpdev
= hpdev
;
1288 pkt
.init_packet
.compl_ctxt
= &comp_pkt
;
1289 pkt
.init_packet
.completion_func
= q_resource_requirements
;
1290 res_req
= (struct pci_child_message
*)&pkt
.init_packet
.message
;
1291 res_req
->message_type
.type
= PCI_QUERY_RESOURCE_REQUIREMENTS
;
1292 res_req
->wslot
.slot
= desc
->win_slot
.slot
;
1294 ret
= vmbus_sendpacket(hbus
->hdev
->channel
, res_req
,
1295 sizeof(struct pci_child_message
),
1296 (unsigned long)&pkt
.init_packet
,
1298 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED
);
1302 wait_for_completion(&comp_pkt
.host_event
);
1304 hpdev
->desc
= *desc
;
1305 get_pcichild(hpdev
, hv_pcidev_ref_initial
);
1306 get_pcichild(hpdev
, hv_pcidev_ref_childlist
);
1307 spin_lock_irqsave(&hbus
->device_list_lock
, flags
);
1308 list_add_tail(&hpdev
->list_entry
, &hbus
->children
);
1309 spin_unlock_irqrestore(&hbus
->device_list_lock
, flags
);
1318 * get_pcichild_wslot() - Find device from slot
1319 * @hbus: Root PCI bus, as understood by this driver
1320 * @wslot: Location on the bus
1322 * This function looks up a PCI device and returns the internal
1323 * representation of it. It acquires a reference on it, so that
1324 * the device won't be deleted while somebody is using it. The
1325 * caller is responsible for calling put_pcichild() to release
1328 * Return: Internal representation of a PCI device
1330 static struct hv_pci_dev
*get_pcichild_wslot(struct hv_pcibus_device
*hbus
,
1333 unsigned long flags
;
1334 struct hv_pci_dev
*iter
, *hpdev
= NULL
;
1336 spin_lock_irqsave(&hbus
->device_list_lock
, flags
);
1337 list_for_each_entry(iter
, &hbus
->children
, list_entry
) {
1338 if (iter
->desc
.win_slot
.slot
== wslot
) {
1340 get_pcichild(hpdev
, hv_pcidev_ref_by_slot
);
1344 spin_unlock_irqrestore(&hbus
->device_list_lock
, flags
);
1350 * pci_devices_present_work() - Handle new list of child devices
1351 * @work: Work struct embedded in struct hv_dr_work
1353 * "Bus Relations" is the Windows term for "children of this
1354 * bus." The terminology is preserved here for people trying to
1355 * debug the interaction between Hyper-V and Linux. This
1356 * function is called when the parent partition reports a list
1357 * of functions that should be observed under this PCI Express
1360 * This function updates the list, and must tolerate being
1361 * called multiple times with the same information. The typical
1362 * number of child devices is one, with very atypical cases
1363 * involving three or four, so the algorithms used here can be
1364 * simple and inefficient.
1366 * It must also treat the omission of a previously observed device as
1367 * notification that the device no longer exists.
1369 * Note that this function is a work item, and it may not be
1370 * invoked in the order that it was queued. Back to back
1371 * updates of the list of present devices may involve queuing
1372 * multiple work items, and this one may run before ones that
1373 * were sent later. As such, this function only does something
1374 * if is the last one in the queue.
1376 static void pci_devices_present_work(struct work_struct
*work
)
1380 struct list_head
*iter
;
1381 struct pci_function_description
*new_desc
;
1382 struct hv_pci_dev
*hpdev
;
1383 struct hv_pcibus_device
*hbus
;
1384 struct list_head removed
;
1385 struct hv_dr_work
*dr_wrk
;
1386 struct hv_dr_state
*dr
= NULL
;
1387 unsigned long flags
;
1389 dr_wrk
= container_of(work
, struct hv_dr_work
, wrk
);
1393 INIT_LIST_HEAD(&removed
);
1395 if (down_interruptible(&hbus
->enum_sem
)) {
1400 /* Pull this off the queue and process it if it was the last one. */
1401 spin_lock_irqsave(&hbus
->device_list_lock
, flags
);
1402 while (!list_empty(&hbus
->dr_list
)) {
1403 dr
= list_first_entry(&hbus
->dr_list
, struct hv_dr_state
,
1405 list_del(&dr
->list_entry
);
1407 /* Throw this away if the list still has stuff in it. */
1408 if (!list_empty(&hbus
->dr_list
)) {
1413 spin_unlock_irqrestore(&hbus
->device_list_lock
, flags
);
1416 up(&hbus
->enum_sem
);
1421 /* First, mark all existing children as reported missing. */
1422 spin_lock_irqsave(&hbus
->device_list_lock
, flags
);
1423 list_for_each(iter
, &hbus
->children
) {
1424 hpdev
= container_of(iter
, struct hv_pci_dev
,
1426 hpdev
->reported_missing
= true;
1428 spin_unlock_irqrestore(&hbus
->device_list_lock
, flags
);
1430 /* Next, add back any reported devices. */
1431 for (child_no
= 0; child_no
< dr
->device_count
; child_no
++) {
1433 new_desc
= &dr
->func
[child_no
];
1435 spin_lock_irqsave(&hbus
->device_list_lock
, flags
);
1436 list_for_each(iter
, &hbus
->children
) {
1437 hpdev
= container_of(iter
, struct hv_pci_dev
,
1439 if ((hpdev
->desc
.win_slot
.slot
==
1440 new_desc
->win_slot
.slot
) &&
1441 (hpdev
->desc
.v_id
== new_desc
->v_id
) &&
1442 (hpdev
->desc
.d_id
== new_desc
->d_id
) &&
1443 (hpdev
->desc
.ser
== new_desc
->ser
)) {
1444 hpdev
->reported_missing
= false;
1448 spin_unlock_irqrestore(&hbus
->device_list_lock
, flags
);
1451 hpdev
= new_pcichild_device(hbus
, new_desc
);
1453 dev_err(&hbus
->hdev
->device
,
1454 "couldn't record a child device.\n");
1458 /* Move missing children to a list on the stack. */
1459 spin_lock_irqsave(&hbus
->device_list_lock
, flags
);
1462 list_for_each(iter
, &hbus
->children
) {
1463 hpdev
= container_of(iter
, struct hv_pci_dev
,
1465 if (hpdev
->reported_missing
) {
1467 put_pcichild(hpdev
, hv_pcidev_ref_childlist
);
1468 list_move_tail(&hpdev
->list_entry
, &removed
);
1473 spin_unlock_irqrestore(&hbus
->device_list_lock
, flags
);
1475 /* Delete everything that should no longer exist. */
1476 while (!list_empty(&removed
)) {
1477 hpdev
= list_first_entry(&removed
, struct hv_pci_dev
,
1479 list_del(&hpdev
->list_entry
);
1480 put_pcichild(hpdev
, hv_pcidev_ref_initial
);
1483 /* Tell the core to rescan bus because there may have been changes. */
1484 if (hbus
->state
== hv_pcibus_installed
) {
1485 pci_lock_rescan_remove();
1486 pci_scan_child_bus(hbus
->pci_bus
);
1487 pci_unlock_rescan_remove();
1489 survey_child_resources(hbus
);
1492 up(&hbus
->enum_sem
);
1498 * hv_pci_devices_present() - Handles list of new children
1499 * @hbus: Root PCI bus, as understood by this driver
1500 * @relations: Packet from host listing children
1502 * This function is invoked whenever a new list of devices for
1505 static void hv_pci_devices_present(struct hv_pcibus_device
*hbus
,
1506 struct pci_bus_relations
*relations
)
1508 struct hv_dr_state
*dr
;
1509 struct hv_dr_work
*dr_wrk
;
1510 unsigned long flags
;
1512 dr_wrk
= kzalloc(sizeof(*dr_wrk
), GFP_NOWAIT
);
1516 dr
= kzalloc(offsetof(struct hv_dr_state
, func
) +
1517 (sizeof(struct pci_function_description
) *
1518 (relations
->device_count
)), GFP_NOWAIT
);
1524 INIT_WORK(&dr_wrk
->wrk
, pci_devices_present_work
);
1526 dr
->device_count
= relations
->device_count
;
1527 if (dr
->device_count
!= 0) {
1528 memcpy(dr
->func
, relations
->func
,
1529 sizeof(struct pci_function_description
) *
1533 spin_lock_irqsave(&hbus
->device_list_lock
, flags
);
1534 list_add_tail(&dr
->list_entry
, &hbus
->dr_list
);
1535 spin_unlock_irqrestore(&hbus
->device_list_lock
, flags
);
1538 schedule_work(&dr_wrk
->wrk
);
1542 * hv_eject_device_work() - Asynchronously handles ejection
1543 * @work: Work struct embedded in internal device struct
1545 * This function handles ejecting a device. Windows will
1546 * attempt to gracefully eject a device, waiting 60 seconds to
1547 * hear back from the guest OS that this completed successfully.
1548 * If this timer expires, the device will be forcibly removed.
1550 static void hv_eject_device_work(struct work_struct
*work
)
1552 struct pci_eject_response
*ejct_pkt
;
1553 struct hv_pci_dev
*hpdev
;
1554 struct pci_dev
*pdev
;
1555 unsigned long flags
;
1558 struct pci_packet pkt
;
1559 u8 buffer
[sizeof(struct pci_eject_response
)];
1562 hpdev
= container_of(work
, struct hv_pci_dev
, wrk
);
1564 if (hpdev
->state
!= hv_pcichild_ejecting
) {
1565 put_pcichild(hpdev
, hv_pcidev_ref_pnp
);
1570 * Ejection can come before or after the PCI bus has been set up, so
1571 * attempt to find it and tear down the bus state, if it exists. This
1572 * must be done without constructs like pci_domain_nr(hbus->pci_bus)
1573 * because hbus->pci_bus may not exist yet.
1575 wslot
= wslot_to_devfn(hpdev
->desc
.win_slot
.slot
);
1576 pdev
= pci_get_domain_bus_and_slot(hpdev
->hbus
->sysdata
.domain
, 0,
1579 pci_stop_and_remove_bus_device(pdev
);
1583 memset(&ctxt
, 0, sizeof(ctxt
));
1584 ejct_pkt
= (struct pci_eject_response
*)&ctxt
.pkt
.message
;
1585 ejct_pkt
->message_type
.type
= PCI_EJECTION_COMPLETE
;
1586 ejct_pkt
->wslot
.slot
= hpdev
->desc
.win_slot
.slot
;
1587 vmbus_sendpacket(hpdev
->hbus
->hdev
->channel
, ejct_pkt
,
1588 sizeof(*ejct_pkt
), (unsigned long)&ctxt
.pkt
,
1589 VM_PKT_DATA_INBAND
, 0);
1591 spin_lock_irqsave(&hpdev
->hbus
->device_list_lock
, flags
);
1592 list_del(&hpdev
->list_entry
);
1593 spin_unlock_irqrestore(&hpdev
->hbus
->device_list_lock
, flags
);
1595 put_pcichild(hpdev
, hv_pcidev_ref_childlist
);
1596 put_pcichild(hpdev
, hv_pcidev_ref_pnp
);
1597 put_hvpcibus(hpdev
->hbus
);
1601 * hv_pci_eject_device() - Handles device ejection
1602 * @hpdev: Internal device tracking struct
1604 * This function is invoked when an ejection packet arrives. It
1605 * just schedules work so that we don't re-enter the packet
1606 * delivery code handling the ejection.
1608 static void hv_pci_eject_device(struct hv_pci_dev
*hpdev
)
1610 hpdev
->state
= hv_pcichild_ejecting
;
1611 get_pcichild(hpdev
, hv_pcidev_ref_pnp
);
1612 INIT_WORK(&hpdev
->wrk
, hv_eject_device_work
);
1613 get_hvpcibus(hpdev
->hbus
);
1614 schedule_work(&hpdev
->wrk
);
1618 * hv_pci_onchannelcallback() - Handles incoming packets
1619 * @context: Internal bus tracking struct
1621 * This function is invoked whenever the host sends a packet to
1622 * this channel (which is private to this root PCI bus).
1624 static void hv_pci_onchannelcallback(void *context
)
1626 const int packet_size
= 0x100;
1628 struct hv_pcibus_device
*hbus
= context
;
1631 struct vmpacket_descriptor
*desc
;
1632 unsigned char *buffer
;
1633 int bufferlen
= packet_size
;
1634 struct pci_packet
*comp_packet
;
1635 struct pci_response
*response
;
1636 struct pci_incoming_message
*new_message
;
1637 struct pci_bus_relations
*bus_rel
;
1638 struct pci_dev_incoming
*dev_message
;
1639 struct hv_pci_dev
*hpdev
;
1641 buffer
= kmalloc(bufferlen
, GFP_ATOMIC
);
1646 ret
= vmbus_recvpacket_raw(hbus
->hdev
->channel
, buffer
,
1647 bufferlen
, &bytes_recvd
, &req_id
);
1649 if (ret
== -ENOBUFS
) {
1651 /* Handle large packet */
1652 bufferlen
= bytes_recvd
;
1653 buffer
= kmalloc(bytes_recvd
, GFP_ATOMIC
);
1659 /* Zero length indicates there are no more packets. */
1660 if (ret
|| !bytes_recvd
)
1664 * All incoming packets must be at least as large as a
1667 if (bytes_recvd
<= sizeof(struct pci_response
))
1669 desc
= (struct vmpacket_descriptor
*)buffer
;
1671 switch (desc
->type
) {
1675 * The host is trusted, and thus it's safe to interpret
1676 * this transaction ID as a pointer.
1678 comp_packet
= (struct pci_packet
*)req_id
;
1679 response
= (struct pci_response
*)buffer
;
1680 comp_packet
->completion_func(comp_packet
->compl_ctxt
,
1685 case VM_PKT_DATA_INBAND
:
1687 new_message
= (struct pci_incoming_message
*)buffer
;
1688 switch (new_message
->message_type
.type
) {
1689 case PCI_BUS_RELATIONS
:
1691 bus_rel
= (struct pci_bus_relations
*)buffer
;
1693 offsetof(struct pci_bus_relations
, func
) +
1694 (sizeof(struct pci_function_description
) *
1695 (bus_rel
->device_count
))) {
1696 dev_err(&hbus
->hdev
->device
,
1697 "bus relations too small\n");
1701 hv_pci_devices_present(hbus
, bus_rel
);
1706 dev_message
= (struct pci_dev_incoming
*)buffer
;
1707 hpdev
= get_pcichild_wslot(hbus
,
1708 dev_message
->wslot
.slot
);
1710 hv_pci_eject_device(hpdev
);
1712 hv_pcidev_ref_by_slot
);
1717 dev_warn(&hbus
->hdev
->device
,
1718 "Unimplemented protocol message %x\n",
1719 new_message
->message_type
.type
);
1725 dev_err(&hbus
->hdev
->device
,
1726 "unhandled packet type %d, tid %llx len %d\n",
1727 desc
->type
, req_id
, bytes_recvd
);
1736 * hv_pci_protocol_negotiation() - Set up protocol
1737 * @hdev: VMBus's tracking struct for this root PCI bus
1739 * This driver is intended to support running on Windows 10
1740 * (server) and later versions. It will not run on earlier
1741 * versions, as they assume that many of the operations which
1742 * Linux needs accomplished with a spinlock held were done via
1743 * asynchronous messaging via VMBus. Windows 10 increases the
1744 * surface area of PCI emulation so that these actions can take
1745 * place by suspending a virtual processor for their duration.
1747 * This function negotiates the channel protocol version,
1748 * failing if the host doesn't support the necessary protocol
1751 static int hv_pci_protocol_negotiation(struct hv_device
*hdev
)
1753 struct pci_version_request
*version_req
;
1754 struct hv_pci_compl comp_pkt
;
1755 struct pci_packet
*pkt
;
1759 * Initiate the handshake with the host and negotiate
1760 * a version that the host can support. We start with the
1761 * highest version number and go down if the host cannot
1764 pkt
= kzalloc(sizeof(*pkt
) + sizeof(*version_req
), GFP_KERNEL
);
1768 init_completion(&comp_pkt
.host_event
);
1769 pkt
->completion_func
= hv_pci_generic_compl
;
1770 pkt
->compl_ctxt
= &comp_pkt
;
1771 version_req
= (struct pci_version_request
*)&pkt
->message
;
1772 version_req
->message_type
.type
= PCI_QUERY_PROTOCOL_VERSION
;
1773 version_req
->protocol_version
= PCI_PROTOCOL_VERSION_CURRENT
;
1775 ret
= vmbus_sendpacket(hdev
->channel
, version_req
,
1776 sizeof(struct pci_version_request
),
1777 (unsigned long)pkt
, VM_PKT_DATA_INBAND
,
1778 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED
);
1782 wait_for_completion(&comp_pkt
.host_event
);
1784 if (comp_pkt
.completion_status
< 0) {
1785 dev_err(&hdev
->device
,
1786 "PCI Pass-through VSP failed version request %x\n",
1787 comp_pkt
.completion_status
);
1800 * hv_pci_free_bridge_windows() - Release memory regions for the
1802 * @hbus: Root PCI bus, as understood by this driver
1804 static void hv_pci_free_bridge_windows(struct hv_pcibus_device
*hbus
)
1807 * Set the resources back to the way they looked when they
1808 * were allocated by setting IORESOURCE_BUSY again.
1811 if (hbus
->low_mmio_space
&& hbus
->low_mmio_res
) {
1812 hbus
->low_mmio_res
->flags
|= IORESOURCE_BUSY
;
1813 vmbus_free_mmio(hbus
->low_mmio_res
->start
,
1814 resource_size(hbus
->low_mmio_res
));
1817 if (hbus
->high_mmio_space
&& hbus
->high_mmio_res
) {
1818 hbus
->high_mmio_res
->flags
|= IORESOURCE_BUSY
;
1819 vmbus_free_mmio(hbus
->high_mmio_res
->start
,
1820 resource_size(hbus
->high_mmio_res
));
1825 * hv_pci_allocate_bridge_windows() - Allocate memory regions
1827 * @hbus: Root PCI bus, as understood by this driver
1829 * This function calls vmbus_allocate_mmio(), which is itself a
1830 * bit of a compromise. Ideally, we might change the pnp layer
1831 * in the kernel such that it comprehends either PCI devices
1832 * which are "grandchildren of ACPI," with some intermediate bus
1833 * node (in this case, VMBus) or change it such that it
1834 * understands VMBus. The pnp layer, however, has been declared
1835 * deprecated, and not subject to change.
1837 * The workaround, implemented here, is to ask VMBus to allocate
1838 * MMIO space for this bus. VMBus itself knows which ranges are
1839 * appropriate by looking at its own ACPI objects. Then, after
1840 * these ranges are claimed, they're modified to look like they
1841 * would have looked if the ACPI and pnp code had allocated
1842 * bridge windows. These descriptors have to exist in this form
1843 * in order to satisfy the code which will get invoked when the
1844 * endpoint PCI function driver calls request_mem_region() or
1845 * request_mem_region_exclusive().
1847 * Return: 0 on success, -errno on failure
1849 static int hv_pci_allocate_bridge_windows(struct hv_pcibus_device
*hbus
)
1851 resource_size_t align
;
1854 if (hbus
->low_mmio_space
) {
1855 align
= 1ULL << (63 - __builtin_clzll(hbus
->low_mmio_space
));
1856 ret
= vmbus_allocate_mmio(&hbus
->low_mmio_res
, hbus
->hdev
, 0,
1857 (u64
)(u32
)0xffffffff,
1858 hbus
->low_mmio_space
,
1861 dev_err(&hbus
->hdev
->device
,
1862 "Need %#llx of low MMIO space. Consider reconfiguring the VM.\n",
1863 hbus
->low_mmio_space
);
1867 /* Modify this resource to become a bridge window. */
1868 hbus
->low_mmio_res
->flags
|= IORESOURCE_WINDOW
;
1869 hbus
->low_mmio_res
->flags
&= ~IORESOURCE_BUSY
;
1870 pci_add_resource(&hbus
->resources_for_children
,
1871 hbus
->low_mmio_res
);
1874 if (hbus
->high_mmio_space
) {
1875 align
= 1ULL << (63 - __builtin_clzll(hbus
->high_mmio_space
));
1876 ret
= vmbus_allocate_mmio(&hbus
->high_mmio_res
, hbus
->hdev
,
1878 hbus
->high_mmio_space
, align
,
1881 dev_err(&hbus
->hdev
->device
,
1882 "Need %#llx of high MMIO space. Consider reconfiguring the VM.\n",
1883 hbus
->high_mmio_space
);
1884 goto release_low_mmio
;
1887 /* Modify this resource to become a bridge window. */
1888 hbus
->high_mmio_res
->flags
|= IORESOURCE_WINDOW
;
1889 hbus
->high_mmio_res
->flags
&= ~IORESOURCE_BUSY
;
1890 pci_add_resource(&hbus
->resources_for_children
,
1891 hbus
->high_mmio_res
);
1897 if (hbus
->low_mmio_res
) {
1898 vmbus_free_mmio(hbus
->low_mmio_res
->start
,
1899 resource_size(hbus
->low_mmio_res
));
1906 * hv_allocate_config_window() - Find MMIO space for PCI Config
1907 * @hbus: Root PCI bus, as understood by this driver
1909 * This function claims memory-mapped I/O space for accessing
1910 * configuration space for the functions on this bus.
1912 * Return: 0 on success, -errno on failure
1914 static int hv_allocate_config_window(struct hv_pcibus_device
*hbus
)
1919 * Set up a region of MMIO space to use for accessing configuration
1922 ret
= vmbus_allocate_mmio(&hbus
->mem_config
, hbus
->hdev
, 0, -1,
1923 PCI_CONFIG_MMIO_LENGTH
, 0x1000, false);
1928 * vmbus_allocate_mmio() gets used for allocating both device endpoint
1929 * resource claims (those which cannot be overlapped) and the ranges
1930 * which are valid for the children of this bus, which are intended
1931 * to be overlapped by those children. Set the flag on this claim
1932 * meaning that this region can't be overlapped.
1935 hbus
->mem_config
->flags
|= IORESOURCE_BUSY
;
1940 static void hv_free_config_window(struct hv_pcibus_device
*hbus
)
1942 vmbus_free_mmio(hbus
->mem_config
->start
, PCI_CONFIG_MMIO_LENGTH
);
1946 * hv_pci_enter_d0() - Bring the "bus" into the D0 power state
1947 * @hdev: VMBus's tracking struct for this root PCI bus
1949 * Return: 0 on success, -errno on failure
1951 static int hv_pci_enter_d0(struct hv_device
*hdev
)
1953 struct hv_pcibus_device
*hbus
= hv_get_drvdata(hdev
);
1954 struct pci_bus_d0_entry
*d0_entry
;
1955 struct hv_pci_compl comp_pkt
;
1956 struct pci_packet
*pkt
;
1960 * Tell the host that the bus is ready to use, and moved into the
1961 * powered-on state. This includes telling the host which region
1962 * of memory-mapped I/O space has been chosen for configuration space
1965 pkt
= kzalloc(sizeof(*pkt
) + sizeof(*d0_entry
), GFP_KERNEL
);
1969 init_completion(&comp_pkt
.host_event
);
1970 pkt
->completion_func
= hv_pci_generic_compl
;
1971 pkt
->compl_ctxt
= &comp_pkt
;
1972 d0_entry
= (struct pci_bus_d0_entry
*)&pkt
->message
;
1973 d0_entry
->message_type
.type
= PCI_BUS_D0ENTRY
;
1974 d0_entry
->mmio_base
= hbus
->mem_config
->start
;
1976 ret
= vmbus_sendpacket(hdev
->channel
, d0_entry
, sizeof(*d0_entry
),
1977 (unsigned long)pkt
, VM_PKT_DATA_INBAND
,
1978 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED
);
1982 wait_for_completion(&comp_pkt
.host_event
);
1984 if (comp_pkt
.completion_status
< 0) {
1985 dev_err(&hdev
->device
,
1986 "PCI Pass-through VSP failed D0 Entry with status %x\n",
1987 comp_pkt
.completion_status
);
2000 * hv_pci_query_relations() - Ask host to send list of child
2002 * @hdev: VMBus's tracking struct for this root PCI bus
2004 * Return: 0 on success, -errno on failure
2006 static int hv_pci_query_relations(struct hv_device
*hdev
)
2008 struct hv_pcibus_device
*hbus
= hv_get_drvdata(hdev
);
2009 struct pci_message message
;
2010 struct completion comp
;
2013 /* Ask the host to send along the list of child devices */
2014 init_completion(&comp
);
2015 if (cmpxchg(&hbus
->survey_event
, NULL
, &comp
))
2018 memset(&message
, 0, sizeof(message
));
2019 message
.type
= PCI_QUERY_BUS_RELATIONS
;
2021 ret
= vmbus_sendpacket(hdev
->channel
, &message
, sizeof(message
),
2022 0, VM_PKT_DATA_INBAND
, 0);
2026 wait_for_completion(&comp
);
2031 * hv_send_resources_allocated() - Report local resource choices
2032 * @hdev: VMBus's tracking struct for this root PCI bus
2034 * The host OS is expecting to be sent a request as a message
2035 * which contains all the resources that the device will use.
2036 * The response contains those same resources, "translated"
2037 * which is to say, the values which should be used by the
2038 * hardware, when it delivers an interrupt. (MMIO resources are
2039 * used in local terms.) This is nice for Windows, and lines up
2040 * with the FDO/PDO split, which doesn't exist in Linux. Linux
2041 * is deeply expecting to scan an emulated PCI configuration
2042 * space. So this message is sent here only to drive the state
2043 * machine on the host forward.
2045 * Return: 0 on success, -errno on failure
2047 static int hv_send_resources_allocated(struct hv_device
*hdev
)
2049 struct hv_pcibus_device
*hbus
= hv_get_drvdata(hdev
);
2050 struct pci_resources_assigned
*res_assigned
;
2051 struct hv_pci_compl comp_pkt
;
2052 struct hv_pci_dev
*hpdev
;
2053 struct pci_packet
*pkt
;
2057 pkt
= kmalloc(sizeof(*pkt
) + sizeof(*res_assigned
), GFP_KERNEL
);
2063 for (wslot
= 0; wslot
< 256; wslot
++) {
2064 hpdev
= get_pcichild_wslot(hbus
, wslot
);
2068 memset(pkt
, 0, sizeof(*pkt
) + sizeof(*res_assigned
));
2069 init_completion(&comp_pkt
.host_event
);
2070 pkt
->completion_func
= hv_pci_generic_compl
;
2071 pkt
->compl_ctxt
= &comp_pkt
;
2072 res_assigned
= (struct pci_resources_assigned
*)&pkt
->message
;
2073 res_assigned
->message_type
.type
= PCI_RESOURCES_ASSIGNED
;
2074 res_assigned
->wslot
.slot
= hpdev
->desc
.win_slot
.slot
;
2076 put_pcichild(hpdev
, hv_pcidev_ref_by_slot
);
2078 ret
= vmbus_sendpacket(
2079 hdev
->channel
, &pkt
->message
,
2080 sizeof(*res_assigned
),
2083 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED
);
2087 wait_for_completion(&comp_pkt
.host_event
);
2089 if (comp_pkt
.completion_status
< 0) {
2091 dev_err(&hdev
->device
,
2092 "resource allocated returned 0x%x",
2093 comp_pkt
.completion_status
);
2103 * hv_send_resources_released() - Report local resources
2105 * @hdev: VMBus's tracking struct for this root PCI bus
2107 * Return: 0 on success, -errno on failure
2109 static int hv_send_resources_released(struct hv_device
*hdev
)
2111 struct hv_pcibus_device
*hbus
= hv_get_drvdata(hdev
);
2112 struct pci_child_message pkt
;
2113 struct hv_pci_dev
*hpdev
;
2117 for (wslot
= 0; wslot
< 256; wslot
++) {
2118 hpdev
= get_pcichild_wslot(hbus
, wslot
);
2122 memset(&pkt
, 0, sizeof(pkt
));
2123 pkt
.message_type
.type
= PCI_RESOURCES_RELEASED
;
2124 pkt
.wslot
.slot
= hpdev
->desc
.win_slot
.slot
;
2126 put_pcichild(hpdev
, hv_pcidev_ref_by_slot
);
2128 ret
= vmbus_sendpacket(hdev
->channel
, &pkt
, sizeof(pkt
), 0,
2129 VM_PKT_DATA_INBAND
, 0);
2137 static void get_hvpcibus(struct hv_pcibus_device
*hbus
)
2139 atomic_inc(&hbus
->remove_lock
);
2142 static void put_hvpcibus(struct hv_pcibus_device
*hbus
)
2144 if (atomic_dec_and_test(&hbus
->remove_lock
))
2145 complete(&hbus
->remove_event
);
2149 * hv_pci_probe() - New VMBus channel probe, for a root PCI bus
2150 * @hdev: VMBus's tracking struct for this root PCI bus
2151 * @dev_id: Identifies the device itself
2153 * Return: 0 on success, -errno on failure
2155 static int hv_pci_probe(struct hv_device
*hdev
,
2156 const struct hv_vmbus_device_id
*dev_id
)
2158 struct hv_pcibus_device
*hbus
;
2161 hbus
= kzalloc(sizeof(*hbus
), GFP_KERNEL
);
2166 * The PCI bus "domain" is what is called "segment" in ACPI and
2167 * other specs. Pull it from the instance ID, to get something
2168 * unique. Bytes 8 and 9 are what is used in Windows guests, so
2169 * do the same thing for consistency. Note that, since this code
2170 * only runs in a Hyper-V VM, Hyper-V can (and does) guarantee
2171 * that (1) the only domain in use for something that looks like
2172 * a physical PCI bus (which is actually emulated by the
2173 * hypervisor) is domain 0 and (2) there will be no overlap
2174 * between domains derived from these instance IDs in the same
2177 hbus
->sysdata
.domain
= hdev
->dev_instance
.b
[9] |
2178 hdev
->dev_instance
.b
[8] << 8;
2181 atomic_inc(&hbus
->remove_lock
);
2182 INIT_LIST_HEAD(&hbus
->children
);
2183 INIT_LIST_HEAD(&hbus
->dr_list
);
2184 INIT_LIST_HEAD(&hbus
->resources_for_children
);
2185 spin_lock_init(&hbus
->config_lock
);
2186 spin_lock_init(&hbus
->device_list_lock
);
2187 sema_init(&hbus
->enum_sem
, 1);
2188 init_completion(&hbus
->remove_event
);
2190 ret
= vmbus_open(hdev
->channel
, pci_ring_size
, pci_ring_size
, NULL
, 0,
2191 hv_pci_onchannelcallback
, hbus
);
2195 hv_set_drvdata(hdev
, hbus
);
2197 ret
= hv_pci_protocol_negotiation(hdev
);
2201 ret
= hv_allocate_config_window(hbus
);
2205 hbus
->cfg_addr
= ioremap(hbus
->mem_config
->start
,
2206 PCI_CONFIG_MMIO_LENGTH
);
2207 if (!hbus
->cfg_addr
) {
2208 dev_err(&hdev
->device
,
2209 "Unable to map a virtual address for config space\n");
2214 hbus
->sysdata
.fwnode
= irq_domain_alloc_fwnode(hbus
);
2215 if (!hbus
->sysdata
.fwnode
) {
2220 ret
= hv_pcie_init_irq_domain(hbus
);
2224 ret
= hv_pci_query_relations(hdev
);
2226 goto free_irq_domain
;
2228 ret
= hv_pci_enter_d0(hdev
);
2230 goto free_irq_domain
;
2232 ret
= hv_pci_allocate_bridge_windows(hbus
);
2234 goto free_irq_domain
;
2236 ret
= hv_send_resources_allocated(hdev
);
2240 prepopulate_bars(hbus
);
2242 hbus
->state
= hv_pcibus_probed
;
2244 ret
= create_root_hv_pci_bus(hbus
);
2251 hv_pci_free_bridge_windows(hbus
);
2253 irq_domain_remove(hbus
->irq_domain
);
2255 irq_domain_free_fwnode(hbus
->sysdata
.fwnode
);
2257 iounmap(hbus
->cfg_addr
);
2259 hv_free_config_window(hbus
);
2261 vmbus_close(hdev
->channel
);
2268 * hv_pci_remove() - Remove routine for this VMBus channel
2269 * @hdev: VMBus's tracking struct for this root PCI bus
2271 * Return: 0 on success, -errno on failure
2273 static int hv_pci_remove(struct hv_device
*hdev
)
2276 struct hv_pcibus_device
*hbus
;
2278 struct pci_packet teardown_packet
;
2281 struct pci_bus_relations relations
;
2282 struct hv_pci_compl comp_pkt
;
2284 hbus
= hv_get_drvdata(hdev
);
2286 memset(&pkt
.teardown_packet
, 0, sizeof(pkt
.teardown_packet
));
2287 init_completion(&comp_pkt
.host_event
);
2288 pkt
.teardown_packet
.completion_func
= hv_pci_generic_compl
;
2289 pkt
.teardown_packet
.compl_ctxt
= &comp_pkt
;
2290 pkt
.teardown_packet
.message
[0].type
= PCI_BUS_D0EXIT
;
2292 ret
= vmbus_sendpacket(hdev
->channel
, &pkt
.teardown_packet
.message
,
2293 sizeof(struct pci_message
),
2294 (unsigned long)&pkt
.teardown_packet
,
2296 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED
);
2298 wait_for_completion_timeout(&comp_pkt
.host_event
, 10 * HZ
);
2300 if (hbus
->state
== hv_pcibus_installed
) {
2301 /* Remove the bus from PCI's point of view. */
2302 pci_lock_rescan_remove();
2303 pci_stop_root_bus(hbus
->pci_bus
);
2304 pci_remove_root_bus(hbus
->pci_bus
);
2305 pci_unlock_rescan_remove();
2308 ret
= hv_send_resources_released(hdev
);
2310 dev_err(&hdev
->device
,
2311 "Couldn't send resources released packet(s)\n");
2313 vmbus_close(hdev
->channel
);
2315 /* Delete any children which might still exist. */
2316 memset(&relations
, 0, sizeof(relations
));
2317 hv_pci_devices_present(hbus
, &relations
);
2319 iounmap(hbus
->cfg_addr
);
2320 hv_free_config_window(hbus
);
2321 pci_free_resource_list(&hbus
->resources_for_children
);
2322 hv_pci_free_bridge_windows(hbus
);
2323 irq_domain_remove(hbus
->irq_domain
);
2324 irq_domain_free_fwnode(hbus
->sysdata
.fwnode
);
2326 wait_for_completion(&hbus
->remove_event
);
2331 static const struct hv_vmbus_device_id hv_pci_id_table
[] = {
2332 /* PCI Pass-through Class ID */
2333 /* 44C4F61D-4444-4400-9D52-802E27EDE19F */
2338 MODULE_DEVICE_TABLE(vmbus
, hv_pci_id_table
);
2340 static struct hv_driver hv_pci_drv
= {
2342 .id_table
= hv_pci_id_table
,
2343 .probe
= hv_pci_probe
,
2344 .remove
= hv_pci_remove
,
2347 static void __exit
exit_hv_pci_drv(void)
2349 vmbus_driver_unregister(&hv_pci_drv
);
2352 static int __init
init_hv_pci_drv(void)
2354 return vmbus_driver_register(&hv_pci_drv
);
2357 module_init(init_hv_pci_drv
);
2358 module_exit(exit_hv_pci_drv
);
2360 MODULE_DESCRIPTION("Hyper-V PCI");
2361 MODULE_LICENSE("GPL v2");