resources+pci: allocator rework (allocation tags)

AddressAllocator now maintains a HashMap<Alloc, (u64, u64, u64)>,
which uniquely maps a Allocation enum (e.g: PciBar(bus, dev, bar),
GpuRenderNode, etc...) to it's address, size, and human-readable tag
/ description.

The interface has also been modified to use Error instead of Option.

Aside from improving debugging, tracking allocations will have
numerous uses in the future. For example, when allocating guest memory
over VmControl sockets, it will be possible to restrict allocations to
pre-allocated slices of memory owned by the requesting device.

To plumb through PCI information to PCI devices, this CL necessitated
the addition of a PciDevice method called `assign_bus_dev`, which
notifies PCI devices of their uniquely assigned Bus and Device numbers.

BUG=chromium:936567
TEST=cargo test -p resources && cargo build --features="gpu gpu-forward"

Change-Id: I8b4b0e32c6f3168138739249ede53d03143ee5c3
Reviewed-on: https://chromium-review.googlesource.com/1536207
Commit-Ready: Daniel Prilik <prilik@google.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Zach Reizner <zachr@chromium.org>

1 files changed, 25 insertions, 5 deletions

diff --git a/devices/src/pci/ac97.rs b/devices/src/pci/ac97.rs
index d883894..aeab1f1 100644
--- a/devices/src/pci/ac97.rs
+++ b/devices/src/pci/ac97.rs
@@ -5,7 +5,7 @@
 use std::os::unix::io::RawFd;
 
 use audio_streams::StreamSource;
-use resources::SystemAllocator;
+use resources::{Alloc, SystemAllocator};
 use sys_util::{error, EventFd, GuestMemory};
 
 use crate::pci::ac97_bus_master::Ac97BusMaster;
@@ -27,6 +27,7 @@ const PCI_DEVICE_ID_INTEL_82801AA_5: u16 = 0x2415;
 /// the audio backend.
 pub struct Ac97Dev {
     config_regs: PciConfiguration,
+    pci_bus_dev: Option<(u8, u8)>,
     // The irq events are temporarily saved here. They need to be passed to the device after the
     // jail forks. This happens when the bus is first written.
     irq_evt: Option<EventFd>,
@@ -52,6 +53,7 @@ impl Ac97Dev {
 
         Ac97Dev {
             config_regs,
+            pci_bus_dev: None,
             irq_evt: None,
             irq_resample_evt: None,
             bus_master: Ac97BusMaster::new(mem, audio_server),
@@ -125,6 +127,10 @@ impl PciDevice for Ac97Dev {
         "AC97".to_owned()
     }
 
+    fn assign_bus_dev(&mut self, bus: u8, device: u8) {
+        self.pci_bus_dev = Some((bus, device));
+    }
+
     fn assign_irq(
         &mut self,
         irq_evt: EventFd,
@@ -138,10 +144,18 @@ impl PciDevice for Ac97Dev {
     }
 
     fn allocate_io_bars(&mut self, resources: &mut SystemAllocator) -> Result<Vec<(u64, u64)>> {
+        let (bus, dev) = self
+            .pci_bus_dev
+            .expect("assign_bus_dev must be called prior to allocate_io_bars");
         let mut ranges = Vec::new();
         let mixer_regs_addr = resources
-            .allocate_mmio_addresses(MIXER_REGS_SIZE)
-            .ok_or(pci_device::Error::IoAllocationFailed(MIXER_REGS_SIZE))?;
+            .mmio_allocator()
+            .allocate(
+                MIXER_REGS_SIZE,
+                Alloc::PciBar { bus, dev, bar: 0 },
+                "ac97-mixer_regs".to_string(),
+            )
+            .map_err(|e| pci_device::Error::IoAllocationFailed(MIXER_REGS_SIZE, e))?;
         let mixer_config = PciBarConfiguration::default()
             .set_register_index(0)
             .set_address(mixer_regs_addr)
@@ -152,8 +166,13 @@ impl PciDevice for Ac97Dev {
         ranges.push((mixer_regs_addr, MIXER_REGS_SIZE));
 
         let master_regs_addr = resources
-            .allocate_mmio_addresses(MASTER_REGS_SIZE)
-            .ok_or_else(|| pci_device::Error::IoAllocationFailed(MASTER_REGS_SIZE))?;
+            .mmio_allocator()
+            .allocate(
+                MASTER_REGS_SIZE,
+                Alloc::PciBar { bus, dev, bar: 1 },
+                "ac97-master_regs".to_string(),
+            )
+            .map_err(|e| pci_device::Error::IoAllocationFailed(MASTER_REGS_SIZE, e))?;
         let master_config = PciBarConfiguration::default()
             .set_register_index(1)
             .set_address(master_regs_addr)
@@ -228,6 +247,7 @@ mod tests {
             .add_device_addresses(0x3000_0000, 0x1000_0000)
             .create_allocator(5, false)
             .unwrap();
+        ac97_dev.assign_bus_dev(0, 0);
         assert!(ac97_dev.allocate_io_bars(&mut allocator).is_ok());
     }
 }