xref: /cloud-hypervisor/pci/src/vfio.rs (revision 99a98f270d8ac3acaff5a24d126e442350469bca)
1 // Copyright © 2019 Intel Corporation
2 //
3 // SPDX-License-Identifier: Apache-2.0 OR BSD-3-Clause
4 //
5 
6 use crate::msi::{MsiConfigState, MSI_CONFIG_ID};
7 use crate::msix::MsixConfigState;
8 use crate::{
9     msi_num_enabled_vectors, BarReprogrammingParams, MsiCap, MsiConfig, MsixCap, MsixConfig,
10     PciBarConfiguration, PciBarPrefetchable, PciBarRegionType, PciBdf, PciCapabilityId,
11     PciClassCode, PciConfiguration, PciDevice, PciDeviceError, PciExpressCapabilityId,
12     PciHeaderType, PciSubclass, MSIX_CONFIG_ID, MSIX_TABLE_ENTRY_SIZE, PCI_CONFIGURATION_ID,
13 };
14 use anyhow::anyhow;
15 use byteorder::{ByteOrder, LittleEndian};
16 use hypervisor::HypervisorVmError;
17 use libc::{sysconf, _SC_PAGESIZE};
18 use std::any::Any;
19 use std::collections::{BTreeMap, HashMap};
20 use std::io;
21 use std::os::unix::io::AsRawFd;
22 use std::ptr::null_mut;
23 use std::sync::{Arc, Barrier, Mutex};
24 use thiserror::Error;
25 use versionize::{VersionMap, Versionize, VersionizeResult};
26 use versionize_derive::Versionize;
27 use vfio_bindings::bindings::vfio::*;
28 use vfio_ioctls::{
29     VfioContainer, VfioDevice, VfioIrq, VfioRegionInfoCap, VfioRegionSparseMmapArea,
30 };
31 use vm_allocator::page_size::{
32     align_page_size_down, align_page_size_up, is_4k_aligned, is_4k_multiple, is_page_size_aligned,
33 };
34 use vm_allocator::{AddressAllocator, SystemAllocator};
35 use vm_device::interrupt::{
36     InterruptIndex, InterruptManager, InterruptSourceGroup, MsiIrqGroupConfig,
37 };
38 use vm_device::{BusDevice, Resource};
39 use vm_memory::{Address, GuestAddress, GuestUsize};
40 use vm_migration::{
41     Migratable, MigratableError, Pausable, Snapshot, Snapshottable, Transportable, VersionMapped,
42 };
43 use vmm_sys_util::eventfd::EventFd;
44 
45 pub(crate) const VFIO_COMMON_ID: &str = "vfio_common";
46 
47 #[derive(Debug, Error)]
48 pub enum VfioPciError {
49     #[error("Failed to create user memory region: {0}")]
50     CreateUserMemoryRegion(#[source] HypervisorVmError),
51     #[error("Failed to DMA map: {0}")]
52     DmaMap(#[source] vfio_ioctls::VfioError),
53     #[error("Failed to DMA unmap: {0}")]
54     DmaUnmap(#[source] vfio_ioctls::VfioError),
55     #[error("Failed to enable INTx: {0}")]
56     EnableIntx(#[source] VfioError),
57     #[error("Failed to enable MSI: {0}")]
58     EnableMsi(#[source] VfioError),
59     #[error("Failed to enable MSI-x: {0}")]
60     EnableMsix(#[source] VfioError),
61     #[error("Failed to mmap the area")]
62     MmapArea,
63     #[error("Failed to notifier's eventfd")]
64     MissingNotifier,
65     #[error("Invalid region alignment")]
66     RegionAlignment,
67     #[error("Invalid region size")]
68     RegionSize,
69     #[error("Failed to retrieve MsiConfigState: {0}")]
70     RetrieveMsiConfigState(#[source] anyhow::Error),
71     #[error("Failed to retrieve MsixConfigState: {0}")]
72     RetrieveMsixConfigState(#[source] anyhow::Error),
73     #[error("Failed to retrieve PciConfigurationState: {0}")]
74     RetrievePciConfigurationState(#[source] anyhow::Error),
75     #[error("Failed to retrieve VfioCommonState: {0}")]
76     RetrieveVfioCommonState(#[source] anyhow::Error),
77 }
78 
79 #[derive(Copy, Clone)]
80 enum PciVfioSubclass {
81     VfioSubclass = 0xff,
82 }
83 
84 impl PciSubclass for PciVfioSubclass {
85     fn get_register_value(&self) -> u8 {
86         *self as u8
87     }
88 }
89 
90 enum InterruptUpdateAction {
91     EnableMsi,
92     DisableMsi,
93     EnableMsix,
94     DisableMsix,
95 }
96 
97 #[derive(Versionize)]
98 struct IntxState {
99     enabled: bool,
100 }
101 
102 pub(crate) struct VfioIntx {
103     interrupt_source_group: Arc<dyn InterruptSourceGroup>,
104     enabled: bool,
105 }
106 
107 #[derive(Versionize)]
108 struct MsiState {
109     cap: MsiCap,
110     cap_offset: u32,
111 }
112 
113 pub(crate) struct VfioMsi {
114     pub(crate) cfg: MsiConfig,
115     cap_offset: u32,
116     interrupt_source_group: Arc<dyn InterruptSourceGroup>,
117 }
118 
119 impl VfioMsi {
120     fn update(&mut self, offset: u64, data: &[u8]) -> Option<InterruptUpdateAction> {
121         let old_enabled = self.cfg.enabled();
122 
123         self.cfg.update(offset, data);
124 
125         let new_enabled = self.cfg.enabled();
126 
127         if !old_enabled && new_enabled {
128             return Some(InterruptUpdateAction::EnableMsi);
129         }
130 
131         if old_enabled && !new_enabled {
132             return Some(InterruptUpdateAction::DisableMsi);
133         }
134 
135         None
136     }
137 }
138 
139 #[derive(Versionize)]
140 struct MsixState {
141     cap: MsixCap,
142     cap_offset: u32,
143     bdf: u32,
144 }
145 
146 pub(crate) struct VfioMsix {
147     pub(crate) bar: MsixConfig,
148     cap: MsixCap,
149     cap_offset: u32,
150     interrupt_source_group: Arc<dyn InterruptSourceGroup>,
151 }
152 
153 impl VfioMsix {
154     fn update(&mut self, offset: u64, data: &[u8]) -> Option<InterruptUpdateAction> {
155         let old_enabled = self.bar.enabled();
156 
157         // Update "Message Control" word
158         if offset == 2 && data.len() == 2 {
159             self.bar.set_msg_ctl(LittleEndian::read_u16(data));
160         }
161 
162         let new_enabled = self.bar.enabled();
163 
164         if !old_enabled && new_enabled {
165             return Some(InterruptUpdateAction::EnableMsix);
166         }
167 
168         if old_enabled && !new_enabled {
169             return Some(InterruptUpdateAction::DisableMsix);
170         }
171 
172         None
173     }
174 
175     fn table_accessed(&self, bar_index: u32, offset: u64) -> bool {
176         let table_offset: u64 = u64::from(self.cap.table_offset());
177         let table_size: u64 = u64::from(self.cap.table_size()) * (MSIX_TABLE_ENTRY_SIZE as u64);
178         let table_bir: u32 = self.cap.table_bir();
179 
180         bar_index == table_bir && offset >= table_offset && offset < table_offset + table_size
181     }
182 }
183 
184 pub(crate) struct Interrupt {
185     pub(crate) intx: Option<VfioIntx>,
186     pub(crate) msi: Option<VfioMsi>,
187     pub(crate) msix: Option<VfioMsix>,
188 }
189 
190 impl Interrupt {
191     fn update_msi(&mut self, offset: u64, data: &[u8]) -> Option<InterruptUpdateAction> {
192         if let Some(ref mut msi) = &mut self.msi {
193             let action = msi.update(offset, data);
194             return action;
195         }
196 
197         None
198     }
199 
200     fn update_msix(&mut self, offset: u64, data: &[u8]) -> Option<InterruptUpdateAction> {
201         if let Some(ref mut msix) = &mut self.msix {
202             let action = msix.update(offset, data);
203             return action;
204         }
205 
206         None
207     }
208 
209     fn accessed(&self, offset: u64) -> Option<(PciCapabilityId, u64)> {
210         if let Some(msi) = &self.msi {
211             if offset >= u64::from(msi.cap_offset)
212                 && offset < u64::from(msi.cap_offset) + msi.cfg.size()
213             {
214                 return Some((
215                     PciCapabilityId::MessageSignalledInterrupts,
216                     u64::from(msi.cap_offset),
217                 ));
218             }
219         }
220 
221         if let Some(msix) = &self.msix {
222             if offset == u64::from(msix.cap_offset) {
223                 return Some((PciCapabilityId::MsiX, u64::from(msix.cap_offset)));
224             }
225         }
226 
227         None
228     }
229 
230     fn msix_table_accessed(&self, bar_index: u32, offset: u64) -> bool {
231         if let Some(msix) = &self.msix {
232             return msix.table_accessed(bar_index, offset);
233         }
234 
235         false
236     }
237 
238     fn msix_write_table(&mut self, offset: u64, data: &[u8]) {
239         if let Some(ref mut msix) = &mut self.msix {
240             let offset = offset - u64::from(msix.cap.table_offset());
241             msix.bar.write_table(offset, data)
242         }
243     }
244 
245     fn msix_read_table(&self, offset: u64, data: &mut [u8]) {
246         if let Some(msix) = &self.msix {
247             let offset = offset - u64::from(msix.cap.table_offset());
248             msix.bar.read_table(offset, data)
249         }
250     }
251 
252     pub(crate) fn intx_in_use(&self) -> bool {
253         if let Some(intx) = &self.intx {
254             return intx.enabled;
255         }
256 
257         false
258     }
259 }
260 
261 #[derive(Copy, Clone)]
262 pub struct UserMemoryRegion {
263     pub slot: u32,
264     pub start: u64,
265     pub size: u64,
266     pub host_addr: u64,
267 }
268 
269 #[derive(Clone)]
270 pub struct MmioRegion {
271     pub start: GuestAddress,
272     pub length: GuestUsize,
273     pub(crate) type_: PciBarRegionType,
274     pub(crate) index: u32,
275     pub(crate) user_memory_regions: Vec<UserMemoryRegion>,
276 }
277 #[derive(Debug, Error)]
278 pub enum VfioError {
279     #[error("Kernel VFIO error: {0}")]
280     KernelVfio(#[source] vfio_ioctls::VfioError),
281     #[error("VFIO user error: {0}")]
282     VfioUser(#[source] vfio_user::Error),
283 }
284 
285 pub(crate) trait Vfio: Send + Sync {
286     fn read_config_byte(&self, offset: u32) -> u8 {
287         let mut data: [u8; 1] = [0];
288         self.read_config(offset, &mut data);
289         data[0]
290     }
291 
292     fn read_config_word(&self, offset: u32) -> u16 {
293         let mut data: [u8; 2] = [0, 0];
294         self.read_config(offset, &mut data);
295         u16::from_le_bytes(data)
296     }
297 
298     fn read_config_dword(&self, offset: u32) -> u32 {
299         let mut data: [u8; 4] = [0, 0, 0, 0];
300         self.read_config(offset, &mut data);
301         u32::from_le_bytes(data)
302     }
303 
304     fn write_config_dword(&self, offset: u32, buf: u32) {
305         let data: [u8; 4] = buf.to_le_bytes();
306         self.write_config(offset, &data)
307     }
308 
309     fn read_config(&self, offset: u32, data: &mut [u8]) {
310         self.region_read(VFIO_PCI_CONFIG_REGION_INDEX, offset.into(), data.as_mut());
311     }
312 
313     fn write_config(&self, offset: u32, data: &[u8]) {
314         self.region_write(VFIO_PCI_CONFIG_REGION_INDEX, offset.into(), data)
315     }
316 
317     fn enable_msi(&self, fds: Vec<&EventFd>) -> Result<(), VfioError> {
318         self.enable_irq(VFIO_PCI_MSI_IRQ_INDEX, fds)
319     }
320 
321     fn disable_msi(&self) -> Result<(), VfioError> {
322         self.disable_irq(VFIO_PCI_MSI_IRQ_INDEX)
323     }
324 
325     fn enable_msix(&self, fds: Vec<&EventFd>) -> Result<(), VfioError> {
326         self.enable_irq(VFIO_PCI_MSIX_IRQ_INDEX, fds)
327     }
328 
329     fn disable_msix(&self) -> Result<(), VfioError> {
330         self.disable_irq(VFIO_PCI_MSIX_IRQ_INDEX)
331     }
332 
333     fn region_read(&self, _index: u32, _offset: u64, _data: &mut [u8]) {
334         unimplemented!()
335     }
336 
337     fn region_write(&self, _index: u32, _offset: u64, _data: &[u8]) {
338         unimplemented!()
339     }
340 
341     fn get_irq_info(&self, _irq_index: u32) -> Option<VfioIrq> {
342         unimplemented!()
343     }
344 
345     fn enable_irq(&self, _irq_index: u32, _event_fds: Vec<&EventFd>) -> Result<(), VfioError> {
346         unimplemented!()
347     }
348 
349     fn disable_irq(&self, _irq_index: u32) -> Result<(), VfioError> {
350         unimplemented!()
351     }
352 
353     fn unmask_irq(&self, _irq_index: u32) -> Result<(), VfioError> {
354         unimplemented!()
355     }
356 }
357 
358 struct VfioDeviceWrapper {
359     device: Arc<VfioDevice>,
360 }
361 
362 impl VfioDeviceWrapper {
363     fn new(device: Arc<VfioDevice>) -> Self {
364         Self { device }
365     }
366 }
367 
368 impl Vfio for VfioDeviceWrapper {
369     fn region_read(&self, index: u32, offset: u64, data: &mut [u8]) {
370         self.device.region_read(index, data, offset)
371     }
372 
373     fn region_write(&self, index: u32, offset: u64, data: &[u8]) {
374         self.device.region_write(index, data, offset)
375     }
376 
377     fn get_irq_info(&self, irq_index: u32) -> Option<VfioIrq> {
378         self.device.get_irq_info(irq_index).copied()
379     }
380 
381     fn enable_irq(&self, irq_index: u32, event_fds: Vec<&EventFd>) -> Result<(), VfioError> {
382         self.device
383             .enable_irq(irq_index, event_fds)
384             .map_err(VfioError::KernelVfio)
385     }
386 
387     fn disable_irq(&self, irq_index: u32) -> Result<(), VfioError> {
388         self.device
389             .disable_irq(irq_index)
390             .map_err(VfioError::KernelVfio)
391     }
392 
393     fn unmask_irq(&self, irq_index: u32) -> Result<(), VfioError> {
394         self.device
395             .unmask_irq(irq_index)
396             .map_err(VfioError::KernelVfio)
397     }
398 }
399 
400 #[derive(Versionize)]
401 struct VfioCommonState {
402     intx_state: Option<IntxState>,
403     msi_state: Option<MsiState>,
404     msix_state: Option<MsixState>,
405 }
406 
407 impl VersionMapped for VfioCommonState {}
408 
409 pub(crate) struct ConfigPatch {
410     mask: u32,
411     patch: u32,
412 }
413 
414 pub(crate) struct VfioCommon {
415     pub(crate) configuration: PciConfiguration,
416     pub(crate) mmio_regions: Vec<MmioRegion>,
417     pub(crate) interrupt: Interrupt,
418     pub(crate) msi_interrupt_manager: Arc<dyn InterruptManager<GroupConfig = MsiIrqGroupConfig>>,
419     pub(crate) legacy_interrupt_group: Option<Arc<dyn InterruptSourceGroup>>,
420     pub(crate) vfio_wrapper: Arc<dyn Vfio>,
421     pub(crate) patches: HashMap<usize, ConfigPatch>,
422 }
423 
424 impl VfioCommon {
425     pub(crate) fn new(
426         msi_interrupt_manager: Arc<dyn InterruptManager<GroupConfig = MsiIrqGroupConfig>>,
427         legacy_interrupt_group: Option<Arc<dyn InterruptSourceGroup>>,
428         vfio_wrapper: Arc<dyn Vfio>,
429         subclass: &dyn PciSubclass,
430         bdf: PciBdf,
431         snapshot: Option<Snapshot>,
432     ) -> Result<Self, VfioPciError> {
433         let pci_configuration_state =
434             vm_migration::versioned_state_from_id(snapshot.as_ref(), PCI_CONFIGURATION_ID)
435                 .map_err(|e| {
436                     VfioPciError::RetrievePciConfigurationState(anyhow!(
437                         "Failed to get PciConfigurationState from Snapshot: {}",
438                         e
439                     ))
440                 })?;
441 
442         let configuration = PciConfiguration::new(
443             0,
444             0,
445             0,
446             PciClassCode::Other,
447             subclass,
448             None,
449             PciHeaderType::Device,
450             0,
451             0,
452             None,
453             pci_configuration_state,
454         );
455 
456         let mut vfio_common = VfioCommon {
457             mmio_regions: Vec::new(),
458             configuration,
459             interrupt: Interrupt {
460                 intx: None,
461                 msi: None,
462                 msix: None,
463             },
464             msi_interrupt_manager,
465             legacy_interrupt_group,
466             vfio_wrapper,
467             patches: HashMap::new(),
468         };
469 
470         let state: Option<VfioCommonState> = snapshot
471             .as_ref()
472             .map(|s| s.to_versioned_state())
473             .transpose()
474             .map_err(|e| {
475                 VfioPciError::RetrieveVfioCommonState(anyhow!(
476                     "Failed to get VfioCommonState from Snapshot: {}",
477                     e
478                 ))
479             })?;
480         let msi_state = vm_migration::versioned_state_from_id(snapshot.as_ref(), MSI_CONFIG_ID)
481             .map_err(|e| {
482                 VfioPciError::RetrieveMsiConfigState(anyhow!(
483                     "Failed to get MsiConfigState from Snapshot: {}",
484                     e
485                 ))
486             })?;
487         let msix_state = vm_migration::versioned_state_from_id(snapshot.as_ref(), MSIX_CONFIG_ID)
488             .map_err(|e| {
489             VfioPciError::RetrieveMsixConfigState(anyhow!(
490                 "Failed to get MsixConfigState from Snapshot: {}",
491                 e
492             ))
493         })?;
494 
495         if let Some(state) = state.as_ref() {
496             vfio_common.set_state(state, msi_state, msix_state)?;
497         } else {
498             vfio_common.parse_capabilities(bdf);
499             vfio_common.initialize_legacy_interrupt()?;
500         }
501 
502         Ok(vfio_common)
503     }
504 
505     /// In case msix table offset is not page size aligned, we need do some fixup to achive it.
506     /// Becuse we don't want the MMIO RW region and trap region overlap each other.
507     fn fixup_msix_region(&mut self, bar_id: u32, region_size: u64) -> u64 {
508         let msix = self.interrupt.msix.as_mut().unwrap();
509         let msix_cap = &mut msix.cap;
510 
511         // Suppose table_bir equals to pba_bir here. Am I right?
512         let (table_offset, table_size) = msix_cap.table_range();
513         if is_page_size_aligned(table_offset) || msix_cap.table_bir() != bar_id {
514             return region_size;
515         }
516 
517         let (pba_offset, pba_size) = msix_cap.pba_range();
518         let msix_sz = align_page_size_up(table_size + pba_size);
519         // Expand region to hold RW and trap region which both page size aligned
520         let size = std::cmp::max(region_size * 2, msix_sz * 2);
521         // let table starts from the middle of the region
522         msix_cap.table_set_offset((size / 2) as u32);
523         msix_cap.pba_set_offset((size / 2 + pba_offset - table_offset) as u32);
524 
525         size
526     }
527 
528     pub(crate) fn allocate_bars(
529         &mut self,
530         allocator: &Arc<Mutex<SystemAllocator>>,
531         mmio_allocator: &mut AddressAllocator,
532         resources: Option<Vec<Resource>>,
533     ) -> Result<Vec<PciBarConfiguration>, PciDeviceError> {
534         let mut bars = Vec::new();
535         let mut bar_id = VFIO_PCI_BAR0_REGION_INDEX;
536 
537         // Going through all regular regions to compute the BAR size.
538         // We're not saving the BAR address to restore it, because we
539         // are going to allocate a guest address for each BAR and write
540         // that new address back.
541         while bar_id < VFIO_PCI_CONFIG_REGION_INDEX {
542             let mut region_size: u64 = 0;
543             let mut region_type = PciBarRegionType::Memory32BitRegion;
544             let mut prefetchable = PciBarPrefetchable::NotPrefetchable;
545             let mut flags: u32 = 0;
546 
547             let mut restored_bar_addr = None;
548             if let Some(resources) = &resources {
549                 for resource in resources {
550                     if let Resource::PciBar {
551                         index,
552                         base,
553                         size,
554                         type_,
555                         ..
556                     } = resource
557                     {
558                         if *index == bar_id as usize {
559                             restored_bar_addr = Some(GuestAddress(*base));
560                             region_size = *size;
561                             region_type = PciBarRegionType::from(*type_);
562                             break;
563                         }
564                     }
565                 }
566                 if restored_bar_addr.is_none() {
567                     bar_id += 1;
568                     continue;
569                 }
570             } else {
571                 let bar_offset = if bar_id == VFIO_PCI_ROM_REGION_INDEX {
572                     (PCI_ROM_EXP_BAR_INDEX * 4) as u32
573                 } else {
574                     PCI_CONFIG_BAR_OFFSET + bar_id * 4
575                 };
576 
577                 // First read flags
578                 flags = self.vfio_wrapper.read_config_dword(bar_offset);
579 
580                 // Is this an IO BAR?
581                 let io_bar = if bar_id != VFIO_PCI_ROM_REGION_INDEX {
582                     matches!(flags & PCI_CONFIG_IO_BAR, PCI_CONFIG_IO_BAR)
583                 } else {
584                     false
585                 };
586 
587                 // Is this a 64-bit BAR?
588                 let is_64bit_bar = if bar_id != VFIO_PCI_ROM_REGION_INDEX {
589                     matches!(
590                         flags & PCI_CONFIG_MEMORY_BAR_64BIT,
591                         PCI_CONFIG_MEMORY_BAR_64BIT
592                     )
593                 } else {
594                     false
595                 };
596 
597                 if matches!(
598                     flags & PCI_CONFIG_BAR_PREFETCHABLE,
599                     PCI_CONFIG_BAR_PREFETCHABLE
600                 ) {
601                     prefetchable = PciBarPrefetchable::Prefetchable
602                 };
603 
604                 // To get size write all 1s
605                 self.vfio_wrapper
606                     .write_config_dword(bar_offset, 0xffff_ffff);
607 
608                 // And read back BAR value. The device will write zeros for bits it doesn't care about
609                 let mut lower = self.vfio_wrapper.read_config_dword(bar_offset);
610 
611                 if io_bar {
612                     // Mask flag bits (lowest 2 for I/O bars)
613                     lower &= !0b11;
614 
615                     // BAR is not enabled
616                     if lower == 0 {
617                         bar_id += 1;
618                         continue;
619                     }
620 
621                     // IO BAR
622                     region_type = PciBarRegionType::IoRegion;
623 
624                     // Invert bits and add 1 to calculate size
625                     region_size = (!lower + 1) as u64;
626                 } else if is_64bit_bar {
627                     // 64 bits Memory BAR
628                     region_type = PciBarRegionType::Memory64BitRegion;
629 
630                     // Query size of upper BAR of 64-bit BAR
631                     let upper_offset: u32 = PCI_CONFIG_BAR_OFFSET + (bar_id + 1) * 4;
632                     self.vfio_wrapper
633                         .write_config_dword(upper_offset, 0xffff_ffff);
634                     let upper = self.vfio_wrapper.read_config_dword(upper_offset);
635 
636                     let mut combined_size = u64::from(upper) << 32 | u64::from(lower);
637 
638                     // Mask out flag bits (lowest 4 for memory bars)
639                     combined_size &= !0b1111;
640 
641                     // BAR is not enabled
642                     if combined_size == 0 {
643                         bar_id += 1;
644                         continue;
645                     }
646 
647                     // Invert and add 1 to to find size
648                     region_size = !combined_size + 1;
649                 } else {
650                     region_type = PciBarRegionType::Memory32BitRegion;
651 
652                     // Mask out flag bits (lowest 4 for memory bars)
653                     lower &= !0b1111;
654 
655                     if lower == 0 {
656                         bar_id += 1;
657                         continue;
658                     }
659 
660                     // Invert and add 1 to to find size
661                     region_size = (!lower + 1) as u64;
662                 }
663             }
664 
665             let bar_addr = match region_type {
666                 PciBarRegionType::IoRegion => {
667                     #[cfg(target_arch = "aarch64")]
668                     unimplemented!();
669 
670                     // The address needs to be 4 bytes aligned.
671                     #[cfg(not(target_arch = "aarch64"))]
672                     allocator
673                         .lock()
674                         .unwrap()
675                         .allocate_io_addresses(restored_bar_addr, region_size, Some(0x4))
676                         .ok_or(PciDeviceError::IoAllocationFailed(region_size))?
677                 }
678                 PciBarRegionType::Memory32BitRegion => {
679                     // BAR allocation must be naturally aligned
680                     allocator
681                         .lock()
682                         .unwrap()
683                         .allocate_mmio_hole_addresses(
684                             restored_bar_addr,
685                             region_size,
686                             Some(region_size),
687                         )
688                         .ok_or(PciDeviceError::IoAllocationFailed(region_size))?
689                 }
690                 PciBarRegionType::Memory64BitRegion => {
691                     // We need do some fixup to keep MMIO RW region and msix cap region page size
692                     // aligned.
693                     region_size = self.fixup_msix_region(bar_id, region_size);
694                     mmio_allocator
695                         .allocate(
696                             restored_bar_addr,
697                             region_size,
698                             // SAFETY: FFI call. Trivially safe.
699                             Some(unsafe { sysconf(_SC_PAGESIZE) as GuestUsize }),
700                         )
701                         .ok_or(PciDeviceError::IoAllocationFailed(region_size))?
702                 }
703             };
704 
705             // We can now build our BAR configuration block.
706             let bar = PciBarConfiguration::default()
707                 .set_index(bar_id as usize)
708                 .set_address(bar_addr.raw_value())
709                 .set_size(region_size)
710                 .set_region_type(region_type)
711                 .set_prefetchable(prefetchable);
712 
713             if bar_id == VFIO_PCI_ROM_REGION_INDEX {
714                 self.configuration
715                     .add_pci_rom_bar(&bar, flags & 0x1)
716                     .map_err(|e| PciDeviceError::IoRegistrationFailed(bar_addr.raw_value(), e))?;
717             } else {
718                 self.configuration
719                     .add_pci_bar(&bar)
720                     .map_err(|e| PciDeviceError::IoRegistrationFailed(bar_addr.raw_value(), e))?;
721             }
722 
723             bars.push(bar);
724             self.mmio_regions.push(MmioRegion {
725                 start: bar_addr,
726                 length: region_size,
727                 type_: region_type,
728                 index: bar_id,
729                 user_memory_regions: Vec::new(),
730             });
731 
732             bar_id += 1;
733             if region_type == PciBarRegionType::Memory64BitRegion {
734                 bar_id += 1;
735             }
736         }
737 
738         Ok(bars)
739     }
740 
741     pub(crate) fn free_bars(
742         &mut self,
743         allocator: &mut SystemAllocator,
744         mmio_allocator: &mut AddressAllocator,
745     ) -> Result<(), PciDeviceError> {
746         for region in self.mmio_regions.iter() {
747             match region.type_ {
748                 PciBarRegionType::IoRegion => {
749                     #[cfg(target_arch = "x86_64")]
750                     allocator.free_io_addresses(region.start, region.length);
751                     #[cfg(target_arch = "aarch64")]
752                     error!("I/O region is not supported");
753                 }
754                 PciBarRegionType::Memory32BitRegion => {
755                     allocator.free_mmio_hole_addresses(region.start, region.length);
756                 }
757                 PciBarRegionType::Memory64BitRegion => {
758                     mmio_allocator.free(region.start, region.length);
759                 }
760             }
761         }
762         Ok(())
763     }
764 
765     pub(crate) fn parse_msix_capabilities(&mut self, cap: u8) -> MsixCap {
766         let msg_ctl = self.vfio_wrapper.read_config_word((cap + 2).into());
767 
768         let table = self.vfio_wrapper.read_config_dword((cap + 4).into());
769 
770         let pba = self.vfio_wrapper.read_config_dword((cap + 8).into());
771 
772         MsixCap {
773             msg_ctl,
774             table,
775             pba,
776         }
777     }
778 
779     pub(crate) fn initialize_msix(
780         &mut self,
781         msix_cap: MsixCap,
782         cap_offset: u32,
783         bdf: PciBdf,
784         state: Option<MsixConfigState>,
785     ) {
786         let interrupt_source_group = self
787             .msi_interrupt_manager
788             .create_group(MsiIrqGroupConfig {
789                 base: 0,
790                 count: msix_cap.table_size() as InterruptIndex,
791             })
792             .unwrap();
793 
794         let msix_config = MsixConfig::new(
795             msix_cap.table_size(),
796             interrupt_source_group.clone(),
797             bdf.into(),
798             state,
799         )
800         .unwrap();
801 
802         self.interrupt.msix = Some(VfioMsix {
803             bar: msix_config,
804             cap: msix_cap,
805             cap_offset,
806             interrupt_source_group,
807         });
808     }
809 
810     pub(crate) fn parse_msi_capabilities(&mut self, cap: u8) -> u16 {
811         self.vfio_wrapper.read_config_word((cap + 2).into())
812     }
813 
814     pub(crate) fn initialize_msi(
815         &mut self,
816         msg_ctl: u16,
817         cap_offset: u32,
818         state: Option<MsiConfigState>,
819     ) {
820         let interrupt_source_group = self
821             .msi_interrupt_manager
822             .create_group(MsiIrqGroupConfig {
823                 base: 0,
824                 count: msi_num_enabled_vectors(msg_ctl) as InterruptIndex,
825             })
826             .unwrap();
827 
828         let msi_config = MsiConfig::new(msg_ctl, interrupt_source_group.clone(), state).unwrap();
829 
830         self.interrupt.msi = Some(VfioMsi {
831             cfg: msi_config,
832             cap_offset,
833             interrupt_source_group,
834         });
835     }
836 
837     pub(crate) fn get_msix_cap_idx(&self) -> Option<usize> {
838         let mut cap_next = self
839             .vfio_wrapper
840             .read_config_byte(PCI_CONFIG_CAPABILITY_OFFSET);
841 
842         while cap_next != 0 {
843             let cap_id = self.vfio_wrapper.read_config_byte(cap_next.into());
844             if PciCapabilityId::from(cap_id) == PciCapabilityId::MsiX {
845                 return Some(cap_next as usize);
846             } else {
847                 cap_next = self.vfio_wrapper.read_config_byte((cap_next + 1).into());
848             }
849         }
850 
851         None
852     }
853 
854     pub(crate) fn parse_capabilities(&mut self, bdf: PciBdf) {
855         let mut cap_next = self
856             .vfio_wrapper
857             .read_config_byte(PCI_CONFIG_CAPABILITY_OFFSET);
858 
859         let mut pci_express_cap_found = false;
860         let mut power_management_cap_found = false;
861 
862         while cap_next != 0 {
863             let cap_id = self.vfio_wrapper.read_config_byte(cap_next.into());
864 
865             match PciCapabilityId::from(cap_id) {
866                 PciCapabilityId::MessageSignalledInterrupts => {
867                     if let Some(irq_info) = self.vfio_wrapper.get_irq_info(VFIO_PCI_MSI_IRQ_INDEX) {
868                         if irq_info.count > 0 {
869                             // Parse capability only if the VFIO device
870                             // supports MSI.
871                             let msg_ctl = self.parse_msi_capabilities(cap_next);
872                             self.initialize_msi(msg_ctl, cap_next as u32, None);
873                         }
874                     }
875                 }
876                 PciCapabilityId::MsiX => {
877                     if let Some(irq_info) = self.vfio_wrapper.get_irq_info(VFIO_PCI_MSIX_IRQ_INDEX)
878                     {
879                         if irq_info.count > 0 {
880                             // Parse capability only if the VFIO device
881                             // supports MSI-X.
882                             let msix_cap = self.parse_msix_capabilities(cap_next);
883                             self.initialize_msix(msix_cap, cap_next as u32, bdf, None);
884                         }
885                     }
886                 }
887                 PciCapabilityId::PciExpress => pci_express_cap_found = true,
888                 PciCapabilityId::PowerManagement => power_management_cap_found = true,
889                 _ => {}
890             };
891 
892             cap_next = self.vfio_wrapper.read_config_byte((cap_next + 1).into());
893         }
894 
895         if pci_express_cap_found && power_management_cap_found {
896             self.parse_extended_capabilities();
897         }
898     }
899 
900     fn parse_extended_capabilities(&mut self) {
901         let mut current_offset = PCI_CONFIG_EXTENDED_CAPABILITY_OFFSET;
902 
903         loop {
904             let ext_cap_hdr = self.vfio_wrapper.read_config_dword(current_offset);
905 
906             let cap_id: u16 = (ext_cap_hdr & 0xffff) as u16;
907             let cap_next: u16 = ((ext_cap_hdr >> 20) & 0xfff) as u16;
908 
909             match PciExpressCapabilityId::from(cap_id) {
910                 PciExpressCapabilityId::AlternativeRoutingIdentificationIntepretation
911                 | PciExpressCapabilityId::ResizeableBar
912                 | PciExpressCapabilityId::SingleRootIoVirtualization => {
913                     let reg_idx = (current_offset / 4) as usize;
914                     self.patches.insert(
915                         reg_idx,
916                         ConfigPatch {
917                             mask: 0x0000_ffff,
918                             patch: PciExpressCapabilityId::NullCapability as u32,
919                         },
920                     );
921                 }
922                 _ => {}
923             }
924 
925             if cap_next == 0 {
926                 break;
927             }
928 
929             current_offset = cap_next.into();
930         }
931     }
932 
933     pub(crate) fn enable_intx(&mut self) -> Result<(), VfioPciError> {
934         if let Some(intx) = &mut self.interrupt.intx {
935             if !intx.enabled {
936                 if let Some(eventfd) = intx.interrupt_source_group.notifier(0) {
937                     self.vfio_wrapper
938                         .enable_irq(VFIO_PCI_INTX_IRQ_INDEX, vec![&eventfd])
939                         .map_err(VfioPciError::EnableIntx)?;
940 
941                     intx.enabled = true;
942                 } else {
943                     return Err(VfioPciError::MissingNotifier);
944                 }
945             }
946         }
947 
948         Ok(())
949     }
950 
951     pub(crate) fn disable_intx(&mut self) {
952         if let Some(intx) = &mut self.interrupt.intx {
953             if intx.enabled {
954                 if let Err(e) = self.vfio_wrapper.disable_irq(VFIO_PCI_INTX_IRQ_INDEX) {
955                     error!("Could not disable INTx: {}", e);
956                 } else {
957                     intx.enabled = false;
958                 }
959             }
960         }
961     }
962 
963     pub(crate) fn enable_msi(&self) -> Result<(), VfioPciError> {
964         if let Some(msi) = &self.interrupt.msi {
965             let mut irq_fds: Vec<EventFd> = Vec::new();
966             for i in 0..msi.cfg.num_enabled_vectors() {
967                 if let Some(eventfd) = msi.interrupt_source_group.notifier(i as InterruptIndex) {
968                     irq_fds.push(eventfd);
969                 } else {
970                     return Err(VfioPciError::MissingNotifier);
971                 }
972             }
973 
974             self.vfio_wrapper
975                 .enable_msi(irq_fds.iter().collect())
976                 .map_err(VfioPciError::EnableMsi)?;
977         }
978 
979         Ok(())
980     }
981 
982     pub(crate) fn disable_msi(&self) {
983         if let Err(e) = self.vfio_wrapper.disable_msi() {
984             error!("Could not disable MSI: {}", e);
985         }
986     }
987 
988     pub(crate) fn enable_msix(&self) -> Result<(), VfioPciError> {
989         if let Some(msix) = &self.interrupt.msix {
990             let mut irq_fds: Vec<EventFd> = Vec::new();
991             for i in 0..msix.bar.table_entries.len() {
992                 if let Some(eventfd) = msix.interrupt_source_group.notifier(i as InterruptIndex) {
993                     irq_fds.push(eventfd);
994                 } else {
995                     return Err(VfioPciError::MissingNotifier);
996                 }
997             }
998 
999             self.vfio_wrapper
1000                 .enable_msix(irq_fds.iter().collect())
1001                 .map_err(VfioPciError::EnableMsix)?;
1002         }
1003 
1004         Ok(())
1005     }
1006 
1007     pub(crate) fn disable_msix(&self) {
1008         if let Err(e) = self.vfio_wrapper.disable_msix() {
1009             error!("Could not disable MSI-X: {}", e);
1010         }
1011     }
1012 
1013     pub(crate) fn initialize_legacy_interrupt(&mut self) -> Result<(), VfioPciError> {
1014         if let Some(irq_info) = self.vfio_wrapper.get_irq_info(VFIO_PCI_INTX_IRQ_INDEX) {
1015             if irq_info.count == 0 {
1016                 // A count of 0 means the INTx IRQ is not supported, therefore
1017                 // it shouldn't be initialized.
1018                 return Ok(());
1019             }
1020         }
1021 
1022         if let Some(interrupt_source_group) = self.legacy_interrupt_group.clone() {
1023             self.interrupt.intx = Some(VfioIntx {
1024                 interrupt_source_group,
1025                 enabled: false,
1026             });
1027 
1028             self.enable_intx()?;
1029         }
1030 
1031         Ok(())
1032     }
1033 
1034     pub(crate) fn update_msi_capabilities(
1035         &mut self,
1036         offset: u64,
1037         data: &[u8],
1038     ) -> Result<(), VfioPciError> {
1039         match self.interrupt.update_msi(offset, data) {
1040             Some(InterruptUpdateAction::EnableMsi) => {
1041                 // Disable INTx before we can enable MSI
1042                 self.disable_intx();
1043                 self.enable_msi()?;
1044             }
1045             Some(InterruptUpdateAction::DisableMsi) => {
1046                 // Fallback onto INTx when disabling MSI
1047                 self.disable_msi();
1048                 self.enable_intx()?;
1049             }
1050             _ => {}
1051         }
1052 
1053         Ok(())
1054     }
1055 
1056     pub(crate) fn update_msix_capabilities(
1057         &mut self,
1058         offset: u64,
1059         data: &[u8],
1060     ) -> Result<(), VfioPciError> {
1061         match self.interrupt.update_msix(offset, data) {
1062             Some(InterruptUpdateAction::EnableMsix) => {
1063                 // Disable INTx before we can enable MSI-X
1064                 self.disable_intx();
1065                 self.enable_msix()?;
1066             }
1067             Some(InterruptUpdateAction::DisableMsix) => {
1068                 // Fallback onto INTx when disabling MSI-X
1069                 self.disable_msix();
1070                 self.enable_intx()?;
1071             }
1072             _ => {}
1073         }
1074 
1075         Ok(())
1076     }
1077 
1078     pub(crate) fn find_region(&self, addr: u64) -> Option<MmioRegion> {
1079         for region in self.mmio_regions.iter() {
1080             if addr >= region.start.raw_value()
1081                 && addr < region.start.unchecked_add(region.length).raw_value()
1082             {
1083                 return Some(region.clone());
1084             }
1085         }
1086         None
1087     }
1088 
1089     pub(crate) fn read_bar(&mut self, base: u64, offset: u64, data: &mut [u8]) {
1090         let addr = base + offset;
1091         if let Some(region) = self.find_region(addr) {
1092             let offset = addr - region.start.raw_value();
1093 
1094             if self.interrupt.msix_table_accessed(region.index, offset) {
1095                 self.interrupt.msix_read_table(offset, data);
1096             } else {
1097                 self.vfio_wrapper.region_read(region.index, offset, data);
1098             }
1099         }
1100 
1101         // INTx EOI
1102         // The guest reading from the BAR potentially means the interrupt has
1103         // been received and can be acknowledged.
1104         if self.interrupt.intx_in_use() {
1105             if let Err(e) = self.vfio_wrapper.unmask_irq(VFIO_PCI_INTX_IRQ_INDEX) {
1106                 error!("Failed unmasking INTx IRQ: {}", e);
1107             }
1108         }
1109     }
1110 
1111     pub(crate) fn write_bar(
1112         &mut self,
1113         base: u64,
1114         offset: u64,
1115         data: &[u8],
1116     ) -> Option<Arc<Barrier>> {
1117         let addr = base + offset;
1118         if let Some(region) = self.find_region(addr) {
1119             let offset = addr - region.start.raw_value();
1120 
1121             // If the MSI-X table is written to, we need to update our cache.
1122             if self.interrupt.msix_table_accessed(region.index, offset) {
1123                 self.interrupt.msix_write_table(offset, data);
1124             } else {
1125                 self.vfio_wrapper.region_write(region.index, offset, data);
1126             }
1127         }
1128 
1129         // INTx EOI
1130         // The guest writing to the BAR potentially means the interrupt has
1131         // been received and can be acknowledged.
1132         if self.interrupt.intx_in_use() {
1133             if let Err(e) = self.vfio_wrapper.unmask_irq(VFIO_PCI_INTX_IRQ_INDEX) {
1134                 error!("Failed unmasking INTx IRQ: {}", e);
1135             }
1136         }
1137 
1138         None
1139     }
1140 
1141     pub(crate) fn write_config_register(
1142         &mut self,
1143         reg_idx: usize,
1144         offset: u64,
1145         data: &[u8],
1146     ) -> Option<Arc<Barrier>> {
1147         // When the guest wants to write to a BAR, we trap it into
1148         // our local configuration space. We're not reprogramming
1149         // VFIO device.
1150         if (PCI_CONFIG_BAR0_INDEX..PCI_CONFIG_BAR0_INDEX + BAR_NUMS).contains(&reg_idx)
1151             || reg_idx == PCI_ROM_EXP_BAR_INDEX
1152         {
1153             // We keep our local cache updated with the BARs.
1154             // We'll read it back from there when the guest is asking
1155             // for BARs (see read_config_register()).
1156             self.configuration
1157                 .write_config_register(reg_idx, offset, data);
1158             return None;
1159         }
1160 
1161         let reg = (reg_idx * PCI_CONFIG_REGISTER_SIZE) as u64;
1162 
1163         // If the MSI or MSI-X capabilities are accessed, we need to
1164         // update our local cache accordingly.
1165         // Depending on how the capabilities are modified, this could
1166         // trigger a VFIO MSI or MSI-X toggle.
1167         if let Some((cap_id, cap_base)) = self.interrupt.accessed(reg) {
1168             let cap_offset: u64 = reg - cap_base + offset;
1169             match cap_id {
1170                 PciCapabilityId::MessageSignalledInterrupts => {
1171                     if let Err(e) = self.update_msi_capabilities(cap_offset, data) {
1172                         error!("Could not update MSI capabilities: {}", e);
1173                     }
1174                 }
1175                 PciCapabilityId::MsiX => {
1176                     if let Err(e) = self.update_msix_capabilities(cap_offset, data) {
1177                         error!("Could not update MSI-X capabilities: {}", e);
1178                     }
1179                 }
1180                 _ => {}
1181             }
1182         }
1183 
1184         // Make sure to write to the device's PCI config space after MSI/MSI-X
1185         // interrupts have been enabled/disabled. In case of MSI, when the
1186         // interrupts are enabled through VFIO (using VFIO_DEVICE_SET_IRQS),
1187         // the MSI Enable bit in the MSI capability structure found in the PCI
1188         // config space is disabled by default. That's why when the guest is
1189         // enabling this bit, we first need to enable the MSI interrupts with
1190         // VFIO through VFIO_DEVICE_SET_IRQS ioctl, and only after we can write
1191         // to the device region to update the MSI Enable bit.
1192         self.vfio_wrapper.write_config((reg + offset) as u32, data);
1193 
1194         None
1195     }
1196 
1197     pub(crate) fn read_config_register(&mut self, reg_idx: usize) -> u32 {
1198         // When reading the BARs, we trap it and return what comes
1199         // from our local configuration space. We want the guest to
1200         // use that and not the VFIO device BARs as it does not map
1201         // with the guest address space.
1202         if (PCI_CONFIG_BAR0_INDEX..PCI_CONFIG_BAR0_INDEX + BAR_NUMS).contains(&reg_idx)
1203             || reg_idx == PCI_ROM_EXP_BAR_INDEX
1204         {
1205             return self.configuration.read_reg(reg_idx);
1206         }
1207 
1208         if let Some(id) = self.get_msix_cap_idx() {
1209             let msix = self.interrupt.msix.as_mut().unwrap();
1210             if reg_idx * 4 == id + 4 {
1211                 return msix.cap.table;
1212             } else if reg_idx * 4 == id + 8 {
1213                 return msix.cap.pba;
1214             }
1215         }
1216 
1217         // Since we don't support passing multi-functions devices, we should
1218         // mask the multi-function bit, bit 7 of the Header Type byte on the
1219         // register 3.
1220         let mask = if reg_idx == PCI_HEADER_TYPE_REG_INDEX {
1221             0xff7f_ffff
1222         } else {
1223             0xffff_ffff
1224         };
1225 
1226         // The config register read comes from the VFIO device itself.
1227         let mut value = self.vfio_wrapper.read_config_dword((reg_idx * 4) as u32) & mask;
1228 
1229         if let Some(config_patch) = self.patches.get(&reg_idx) {
1230             value = (value & !config_patch.mask) | config_patch.patch;
1231         }
1232 
1233         value
1234     }
1235 
1236     fn state(&self) -> VfioCommonState {
1237         let intx_state = self.interrupt.intx.as_ref().map(|intx| IntxState {
1238             enabled: intx.enabled,
1239         });
1240 
1241         let msi_state = self.interrupt.msi.as_ref().map(|msi| MsiState {
1242             cap: msi.cfg.cap,
1243             cap_offset: msi.cap_offset,
1244         });
1245 
1246         let msix_state = self.interrupt.msix.as_ref().map(|msix| MsixState {
1247             cap: msix.cap,
1248             cap_offset: msix.cap_offset,
1249             bdf: msix.bar.devid,
1250         });
1251 
1252         VfioCommonState {
1253             intx_state,
1254             msi_state,
1255             msix_state,
1256         }
1257     }
1258 
1259     fn set_state(
1260         &mut self,
1261         state: &VfioCommonState,
1262         msi_state: Option<MsiConfigState>,
1263         msix_state: Option<MsixConfigState>,
1264     ) -> Result<(), VfioPciError> {
1265         if let (Some(intx), Some(interrupt_source_group)) =
1266             (&state.intx_state, self.legacy_interrupt_group.clone())
1267         {
1268             self.interrupt.intx = Some(VfioIntx {
1269                 interrupt_source_group,
1270                 enabled: false,
1271             });
1272 
1273             if intx.enabled {
1274                 self.enable_intx()?;
1275             }
1276         }
1277 
1278         if let Some(msi) = &state.msi_state {
1279             self.initialize_msi(msi.cap.msg_ctl, msi.cap_offset, msi_state);
1280         }
1281 
1282         if let Some(msix) = &state.msix_state {
1283             self.initialize_msix(msix.cap, msix.cap_offset, msix.bdf.into(), msix_state);
1284         }
1285 
1286         Ok(())
1287     }
1288 }
1289 
1290 impl Pausable for VfioCommon {}
1291 
1292 impl Snapshottable for VfioCommon {
1293     fn id(&self) -> String {
1294         String::from(VFIO_COMMON_ID)
1295     }
1296 
1297     fn snapshot(&mut self) -> std::result::Result<Snapshot, MigratableError> {
1298         let mut vfio_common_snapshot = Snapshot::new_from_versioned_state(&self.state())?;
1299 
1300         // Snapshot PciConfiguration
1301         vfio_common_snapshot.add_snapshot(self.configuration.id(), self.configuration.snapshot()?);
1302 
1303         // Snapshot MSI
1304         if let Some(msi) = &mut self.interrupt.msi {
1305             vfio_common_snapshot.add_snapshot(msi.cfg.id(), msi.cfg.snapshot()?);
1306         }
1307 
1308         // Snapshot MSI-X
1309         if let Some(msix) = &mut self.interrupt.msix {
1310             vfio_common_snapshot.add_snapshot(msix.bar.id(), msix.bar.snapshot()?);
1311         }
1312 
1313         Ok(vfio_common_snapshot)
1314     }
1315 }
1316 
1317 /// VfioPciDevice represents a VFIO PCI device.
1318 /// This structure implements the BusDevice and PciDevice traits.
1319 ///
1320 /// A VfioPciDevice is bound to a VfioDevice and is also a PCI device.
1321 /// The VMM creates a VfioDevice, then assigns it to a VfioPciDevice,
1322 /// which then gets added to the PCI bus.
1323 pub struct VfioPciDevice {
1324     id: String,
1325     vm: Arc<dyn hypervisor::Vm>,
1326     device: Arc<VfioDevice>,
1327     container: Arc<VfioContainer>,
1328     common: VfioCommon,
1329     iommu_attached: bool,
1330     memory_slot: Arc<dyn Fn() -> u32 + Send + Sync>,
1331 }
1332 
1333 impl VfioPciDevice {
1334     /// Constructs a new Vfio Pci device for the given Vfio device
1335     #[allow(clippy::too_many_arguments)]
1336     pub fn new(
1337         id: String,
1338         vm: &Arc<dyn hypervisor::Vm>,
1339         device: VfioDevice,
1340         container: Arc<VfioContainer>,
1341         msi_interrupt_manager: Arc<dyn InterruptManager<GroupConfig = MsiIrqGroupConfig>>,
1342         legacy_interrupt_group: Option<Arc<dyn InterruptSourceGroup>>,
1343         iommu_attached: bool,
1344         bdf: PciBdf,
1345         memory_slot: Arc<dyn Fn() -> u32 + Send + Sync>,
1346         snapshot: Option<Snapshot>,
1347     ) -> Result<Self, VfioPciError> {
1348         let device = Arc::new(device);
1349         device.reset();
1350 
1351         let vfio_wrapper = VfioDeviceWrapper::new(Arc::clone(&device));
1352 
1353         let common = VfioCommon::new(
1354             msi_interrupt_manager,
1355             legacy_interrupt_group,
1356             Arc::new(vfio_wrapper) as Arc<dyn Vfio>,
1357             &PciVfioSubclass::VfioSubclass,
1358             bdf,
1359             vm_migration::snapshot_from_id(snapshot.as_ref(), VFIO_COMMON_ID),
1360         )?;
1361 
1362         let vfio_pci_device = VfioPciDevice {
1363             id,
1364             vm: vm.clone(),
1365             device,
1366             container,
1367             common,
1368             iommu_attached,
1369             memory_slot,
1370         };
1371 
1372         Ok(vfio_pci_device)
1373     }
1374 
1375     pub fn iommu_attached(&self) -> bool {
1376         self.iommu_attached
1377     }
1378 
1379     fn generate_sparse_areas(
1380         caps: &[VfioRegionInfoCap],
1381         region_index: u32,
1382         region_start: u64,
1383         region_size: u64,
1384         vfio_msix: Option<&VfioMsix>,
1385     ) -> Result<Vec<VfioRegionSparseMmapArea>, VfioPciError> {
1386         for cap in caps {
1387             match cap {
1388                 VfioRegionInfoCap::SparseMmap(sparse_mmap) => return Ok(sparse_mmap.areas.clone()),
1389                 VfioRegionInfoCap::MsixMappable => {
1390                     if !is_4k_aligned(region_start) {
1391                         error!(
1392                             "Region start address 0x{:x} must be at least aligned on 4KiB",
1393                             region_start
1394                         );
1395                         return Err(VfioPciError::RegionAlignment);
1396                     }
1397                     if !is_4k_multiple(region_size) {
1398                         error!(
1399                             "Region size 0x{:x} must be at least a multiple of 4KiB",
1400                             region_size
1401                         );
1402                         return Err(VfioPciError::RegionSize);
1403                     }
1404 
1405                     // In case the region contains the MSI-X vectors table or
1406                     // the MSI-X PBA table, we must calculate the subregions
1407                     // around them, leading to a list of sparse areas.
1408                     // We want to make sure we will still trap MMIO accesses
1409                     // to these MSI-X specific ranges. If these region don't align
1410                     // with pagesize, we can achive it by enlarging its range.
1411                     //
1412                     // Using a BtreeMap as the list provided through the iterator is sorted
1413                     // by key. This ensures proper split of the whole region.
1414                     let mut inter_ranges = BTreeMap::new();
1415                     if let Some(msix) = vfio_msix {
1416                         if region_index == msix.cap.table_bir() {
1417                             let (offset, size) = msix.cap.table_range();
1418                             let offset = align_page_size_down(offset);
1419                             let size = align_page_size_up(size);
1420                             inter_ranges.insert(offset, size);
1421                         }
1422                         if region_index == msix.cap.pba_bir() {
1423                             let (offset, size) = msix.cap.pba_range();
1424                             let offset = align_page_size_down(offset);
1425                             let size = align_page_size_up(size);
1426                             inter_ranges.insert(offset, size);
1427                         }
1428                     }
1429 
1430                     let mut sparse_areas = Vec::new();
1431                     let mut current_offset = 0;
1432                     for (range_offset, range_size) in inter_ranges {
1433                         if range_offset > current_offset {
1434                             sparse_areas.push(VfioRegionSparseMmapArea {
1435                                 offset: current_offset,
1436                                 size: range_offset - current_offset,
1437                             });
1438                         }
1439                         current_offset = align_page_size_down(range_offset + range_size);
1440                     }
1441 
1442                     if region_size > current_offset {
1443                         sparse_areas.push(VfioRegionSparseMmapArea {
1444                             offset: current_offset,
1445                             size: region_size - current_offset,
1446                         });
1447                     }
1448 
1449                     return Ok(sparse_areas);
1450                 }
1451                 _ => {}
1452             }
1453         }
1454 
1455         // In case no relevant capabilities have been found, create a single
1456         // sparse area corresponding to the entire MMIO region.
1457         Ok(vec![VfioRegionSparseMmapArea {
1458             offset: 0,
1459             size: region_size,
1460         }])
1461     }
1462 
1463     /// Map MMIO regions into the guest, and avoid VM exits when the guest tries
1464     /// to reach those regions.
1465     ///
1466     /// # Arguments
1467     ///
1468     /// * `vm` - The VM object. It is used to set the VFIO MMIO regions
1469     ///          as user memory regions.
1470     /// * `mem_slot` - The closure to return a memory slot.
1471     pub fn map_mmio_regions(&mut self) -> Result<(), VfioPciError> {
1472         let fd = self.device.as_raw_fd();
1473 
1474         for region in self.common.mmio_regions.iter_mut() {
1475             let region_flags = self.device.get_region_flags(region.index);
1476             if region_flags & VFIO_REGION_INFO_FLAG_MMAP != 0 {
1477                 let mut prot = 0;
1478                 if region_flags & VFIO_REGION_INFO_FLAG_READ != 0 {
1479                     prot |= libc::PROT_READ;
1480                 }
1481                 if region_flags & VFIO_REGION_INFO_FLAG_WRITE != 0 {
1482                     prot |= libc::PROT_WRITE;
1483                 }
1484 
1485                 // Retrieve the list of capabilities found on the region
1486                 let caps = if region_flags & VFIO_REGION_INFO_FLAG_CAPS != 0 {
1487                     self.device.get_region_caps(region.index)
1488                 } else {
1489                     Vec::new()
1490                 };
1491 
1492                 // Don't try to mmap the region if it contains MSI-X table or
1493                 // MSI-X PBA subregion, and if we couldn't find MSIX_MAPPABLE
1494                 // in the list of supported capabilities.
1495                 if let Some(msix) = self.common.interrupt.msix.as_ref() {
1496                     if (region.index == msix.cap.table_bir() || region.index == msix.cap.pba_bir())
1497                         && !caps.contains(&VfioRegionInfoCap::MsixMappable)
1498                     {
1499                         continue;
1500                     }
1501                 }
1502 
1503                 let mmap_size = self.device.get_region_size(region.index);
1504                 let mmap_offset = self.device.get_region_offset(region.index);
1505 
1506                 let sparse_areas = Self::generate_sparse_areas(
1507                     &caps,
1508                     region.index,
1509                     region.start.0,
1510                     mmap_size,
1511                     self.common.interrupt.msix.as_ref(),
1512                 )?;
1513 
1514                 for area in sparse_areas.iter() {
1515                     // SAFETY: FFI call with correct arguments
1516                     let host_addr = unsafe {
1517                         libc::mmap(
1518                             null_mut(),
1519                             area.size as usize,
1520                             prot,
1521                             libc::MAP_SHARED,
1522                             fd,
1523                             mmap_offset as libc::off_t + area.offset as libc::off_t,
1524                         )
1525                     };
1526 
1527                     if host_addr == libc::MAP_FAILED {
1528                         error!(
1529                             "Could not mmap sparse area (offset = 0x{:x}, size = 0x{:x}): {}",
1530                             area.offset,
1531                             area.size,
1532                             std::io::Error::last_os_error()
1533                         );
1534                         return Err(VfioPciError::MmapArea);
1535                     }
1536 
1537                     if !is_page_size_aligned(area.size) || !is_page_size_aligned(area.offset) {
1538                         warn!(
1539                             "Could not mmap sparse area that is not page size aligned (offset = 0x{:x}, size = 0x{:x})",
1540                             area.offset,
1541                             area.size,
1542                             );
1543                         return Ok(());
1544                     }
1545 
1546                     let user_memory_region = UserMemoryRegion {
1547                         slot: (self.memory_slot)(),
1548                         start: region.start.0 + area.offset,
1549                         size: area.size,
1550                         host_addr: host_addr as u64,
1551                     };
1552 
1553                     region.user_memory_regions.push(user_memory_region);
1554 
1555                     let mem_region = self.vm.make_user_memory_region(
1556                         user_memory_region.slot,
1557                         user_memory_region.start,
1558                         user_memory_region.size,
1559                         user_memory_region.host_addr,
1560                         false,
1561                         false,
1562                     );
1563 
1564                     self.vm
1565                         .create_user_memory_region(mem_region)
1566                         .map_err(VfioPciError::CreateUserMemoryRegion)?;
1567                 }
1568             }
1569         }
1570 
1571         Ok(())
1572     }
1573 
1574     pub fn unmap_mmio_regions(&mut self) {
1575         for region in self.common.mmio_regions.iter() {
1576             for user_memory_region in region.user_memory_regions.iter() {
1577                 // Remove region
1578                 let r = self.vm.make_user_memory_region(
1579                     user_memory_region.slot,
1580                     user_memory_region.start,
1581                     user_memory_region.size,
1582                     user_memory_region.host_addr,
1583                     false,
1584                     false,
1585                 );
1586 
1587                 if let Err(e) = self.vm.remove_user_memory_region(r) {
1588                     error!("Could not remove the userspace memory region: {}", e);
1589                 }
1590 
1591                 // SAFETY: FFI call with correct arguments
1592                 let ret = unsafe {
1593                     libc::munmap(
1594                         user_memory_region.host_addr as *mut libc::c_void,
1595                         user_memory_region.size as usize,
1596                     )
1597                 };
1598                 if ret != 0 {
1599                     error!(
1600                         "Could not unmap region {}, error:{}",
1601                         region.index,
1602                         io::Error::last_os_error()
1603                     );
1604                 }
1605             }
1606         }
1607     }
1608 
1609     pub fn dma_map(&self, iova: u64, size: u64, user_addr: u64) -> Result<(), VfioPciError> {
1610         if !self.iommu_attached {
1611             self.container
1612                 .vfio_dma_map(iova, size, user_addr)
1613                 .map_err(VfioPciError::DmaMap)?;
1614         }
1615 
1616         Ok(())
1617     }
1618 
1619     pub fn dma_unmap(&self, iova: u64, size: u64) -> Result<(), VfioPciError> {
1620         if !self.iommu_attached {
1621             self.container
1622                 .vfio_dma_unmap(iova, size)
1623                 .map_err(VfioPciError::DmaUnmap)?;
1624         }
1625 
1626         Ok(())
1627     }
1628 
1629     pub fn mmio_regions(&self) -> Vec<MmioRegion> {
1630         self.common.mmio_regions.clone()
1631     }
1632 }
1633 
1634 impl Drop for VfioPciDevice {
1635     fn drop(&mut self) {
1636         self.unmap_mmio_regions();
1637 
1638         if let Some(msix) = &self.common.interrupt.msix {
1639             if msix.bar.enabled() {
1640                 self.common.disable_msix();
1641             }
1642         }
1643 
1644         if let Some(msi) = &self.common.interrupt.msi {
1645             if msi.cfg.enabled() {
1646                 self.common.disable_msi()
1647             }
1648         }
1649 
1650         if self.common.interrupt.intx_in_use() {
1651             self.common.disable_intx();
1652         }
1653     }
1654 }
1655 
1656 impl BusDevice for VfioPciDevice {
1657     fn read(&mut self, base: u64, offset: u64, data: &mut [u8]) {
1658         self.read_bar(base, offset, data)
1659     }
1660 
1661     fn write(&mut self, base: u64, offset: u64, data: &[u8]) -> Option<Arc<Barrier>> {
1662         self.write_bar(base, offset, data)
1663     }
1664 }
1665 
1666 // First BAR offset in the PCI config space.
1667 const PCI_CONFIG_BAR_OFFSET: u32 = 0x10;
1668 // Capability register offset in the PCI config space.
1669 const PCI_CONFIG_CAPABILITY_OFFSET: u32 = 0x34;
1670 // Extended capabilities register offset in the PCI config space.
1671 const PCI_CONFIG_EXTENDED_CAPABILITY_OFFSET: u32 = 0x100;
1672 // IO BAR when first BAR bit is 1.
1673 const PCI_CONFIG_IO_BAR: u32 = 0x1;
1674 // 64-bit memory bar flag.
1675 const PCI_CONFIG_MEMORY_BAR_64BIT: u32 = 0x4;
1676 // Prefetchable BAR bit
1677 const PCI_CONFIG_BAR_PREFETCHABLE: u32 = 0x8;
1678 // PCI config register size (4 bytes).
1679 const PCI_CONFIG_REGISTER_SIZE: usize = 4;
1680 // Number of BARs for a PCI device
1681 const BAR_NUMS: usize = 6;
1682 // PCI Header Type register index
1683 const PCI_HEADER_TYPE_REG_INDEX: usize = 3;
1684 // First BAR register index
1685 const PCI_CONFIG_BAR0_INDEX: usize = 4;
1686 // PCI ROM expansion BAR register index
1687 const PCI_ROM_EXP_BAR_INDEX: usize = 12;
1688 
1689 impl PciDevice for VfioPciDevice {
1690     fn allocate_bars(
1691         &mut self,
1692         allocator: &Arc<Mutex<SystemAllocator>>,
1693         mmio_allocator: &mut AddressAllocator,
1694         resources: Option<Vec<Resource>>,
1695     ) -> Result<Vec<PciBarConfiguration>, PciDeviceError> {
1696         self.common
1697             .allocate_bars(allocator, mmio_allocator, resources)
1698     }
1699 
1700     fn free_bars(
1701         &mut self,
1702         allocator: &mut SystemAllocator,
1703         mmio_allocator: &mut AddressAllocator,
1704     ) -> Result<(), PciDeviceError> {
1705         self.common.free_bars(allocator, mmio_allocator)
1706     }
1707 
1708     fn write_config_register(
1709         &mut self,
1710         reg_idx: usize,
1711         offset: u64,
1712         data: &[u8],
1713     ) -> Option<Arc<Barrier>> {
1714         self.common.write_config_register(reg_idx, offset, data)
1715     }
1716 
1717     fn read_config_register(&mut self, reg_idx: usize) -> u32 {
1718         self.common.read_config_register(reg_idx)
1719     }
1720 
1721     fn detect_bar_reprogramming(
1722         &mut self,
1723         reg_idx: usize,
1724         data: &[u8],
1725     ) -> Option<BarReprogrammingParams> {
1726         self.common
1727             .configuration
1728             .detect_bar_reprogramming(reg_idx, data)
1729     }
1730 
1731     fn read_bar(&mut self, base: u64, offset: u64, data: &mut [u8]) {
1732         self.common.read_bar(base, offset, data)
1733     }
1734 
1735     fn write_bar(&mut self, base: u64, offset: u64, data: &[u8]) -> Option<Arc<Barrier>> {
1736         self.common.write_bar(base, offset, data)
1737     }
1738 
1739     fn move_bar(&mut self, old_base: u64, new_base: u64) -> Result<(), io::Error> {
1740         for region in self.common.mmio_regions.iter_mut() {
1741             if region.start.raw_value() == old_base {
1742                 region.start = GuestAddress(new_base);
1743 
1744                 for user_memory_region in region.user_memory_regions.iter_mut() {
1745                     // Remove old region
1746                     let old_mem_region = self.vm.make_user_memory_region(
1747                         user_memory_region.slot,
1748                         user_memory_region.start,
1749                         user_memory_region.size,
1750                         user_memory_region.host_addr,
1751                         false,
1752                         false,
1753                     );
1754 
1755                     self.vm
1756                         .remove_user_memory_region(old_mem_region)
1757                         .map_err(|e| io::Error::new(io::ErrorKind::Other, e))?;
1758 
1759                     // Update the user memory region with the correct start address.
1760                     if new_base > old_base {
1761                         user_memory_region.start += new_base - old_base;
1762                     } else {
1763                         user_memory_region.start -= old_base - new_base;
1764                     }
1765 
1766                     // Insert new region
1767                     let new_mem_region = self.vm.make_user_memory_region(
1768                         user_memory_region.slot,
1769                         user_memory_region.start,
1770                         user_memory_region.size,
1771                         user_memory_region.host_addr,
1772                         false,
1773                         false,
1774                     );
1775 
1776                     self.vm
1777                         .create_user_memory_region(new_mem_region)
1778                         .map_err(|e| io::Error::new(io::ErrorKind::Other, e))?;
1779                 }
1780             }
1781         }
1782 
1783         Ok(())
1784     }
1785 
1786     fn as_any(&mut self) -> &mut dyn Any {
1787         self
1788     }
1789 
1790     fn id(&self) -> Option<String> {
1791         Some(self.id.clone())
1792     }
1793 }
1794 
1795 impl Pausable for VfioPciDevice {}
1796 
1797 impl Snapshottable for VfioPciDevice {
1798     fn id(&self) -> String {
1799         self.id.clone()
1800     }
1801 
1802     fn snapshot(&mut self) -> std::result::Result<Snapshot, MigratableError> {
1803         let mut vfio_pci_dev_snapshot = Snapshot::default();
1804 
1805         // Snapshot VfioCommon
1806         vfio_pci_dev_snapshot.add_snapshot(self.common.id(), self.common.snapshot()?);
1807 
1808         Ok(vfio_pci_dev_snapshot)
1809     }
1810 }
1811 impl Transportable for VfioPciDevice {}
1812 impl Migratable for VfioPciDevice {}
1813