acpi: extend acpi pm worker to listen on acpi_event

In order to listen on acpi_mc_group of acpi_event family there is need
to query kernel about it's group id, which is next used to create ACPI
event related socket. This socket is next used during ACPI PM worker's
wait context build.

Upon receiving ACPI events, dispatch them by device class and in case of
receiving "gpe" one, emulate proper vGPE and inject vSCI to the guest.

BUG=b:197247746, b:205072342
TEST=Receive, parse and use GPE generated by ACPI events. With use of
additional kernel patches make sure that GPE notifications are correctly
received, emulated and vSCI injected to the guest.

Change-Id: I18bdfe18ebb1e5bcfa7277b91ae195a61fac1a3d
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/crosvm/+/3407321
Reviewed-by: Daniel Verkamp <dverkamp@chromium.org>
Tested-by: kokoro <noreply+kokoro@google.com>
Commit-Queue: Tomasz Nowicki <tnowicki@google.com>

base/src/lib.rs

@@ -43,6 +43,7 @@ pub use sys_util::{
     ScmSocket, UnlinkUnixListener,
 };
 pub use sys_util::{pagesize, round_up_to_page_size};
+pub use sys_util::{AcpiNotifyEvent, NetlinkGenericSocket};
 pub use sys_util::{Clock, FakeClock};
 pub use sys_util::{EpollContext, EpollEvents};
 pub use sys_util::{ExternalMapping, ExternalMappingError, ExternalMappingResult};

devices/src/acpi.rs

@@ -4,7 +4,8 @@
 
 use crate::{BusAccessInfo, BusDevice, BusResumeDevice};
 use acpi_tables::{aml, aml::Aml};
-use base::{error, warn, Error as SysError, Event, PollToken, WaitContext};
+use base::{error, info, warn, Error as SysError, Event, PollToken, WaitContext};
+use base::{AcpiNotifyEvent, NetlinkGenericSocket};
 use std::sync::Arc;
 use std::thread;
 use sync::Mutex;
@@ -22,6 +23,10 @@ pub enum ACPIPMError {
     /// Error while waiting for events.
     #[error("failed to wait for events: {0}")]
     WaitError(SysError),
+    #[error("Did not found group_id corresponding to acpi_mc_group")]
+    AcpiMcGroupError,
+    #[error("Failed to create and bind NETLINK_GENERIC socket, listening on acpi_mc_group: {0}")]
+    AcpiEventSockError(base::Error),
 }
 
 struct Pm1Resource {
@@ -156,8 +161,28 @@ fn run_worker(
     gpe0: Arc<Mutex<GpeResource>>,
     #[cfg(feature = "direct")] sci_direct_evt: Option<(Event, Event)>,
 ) -> Result<(), ACPIPMError> {
+    // Get group id corresponding to acpi_mc_group of acpi_event family
+    let nl_groups: u32;
+    match get_acpi_event_group() {
+        Some(group) => {
+            nl_groups = 1 << (group - 1);
+            info!("Listening on acpi_mc_group of acpi_event family");
+        }
+        None => {
+            return Err(ACPIPMError::AcpiMcGroupError);
+        }
+    }
+
+    let acpi_event_sock = match NetlinkGenericSocket::new(nl_groups) {
+        Ok(acpi_sock) => acpi_sock,
+        Err(e) => {
+            return Err(ACPIPMError::AcpiEventSockError(e));
+        }
+    };
+
     #[derive(PollToken)]
     enum Token {
+        AcpiEvent,
         InterruptResample,
         #[cfg(feature = "direct")]
         InterruptTriggerDirect,
@@ -165,6 +190,7 @@ fn run_worker(
     }
 
     let wait_ctx: WaitContext<Token> = WaitContext::build_with(&[
+        (&acpi_event_sock, Token::AcpiEvent),
         (&sci_resample, Token::InterruptResample),
         (&kill_evt, Token::Kill),
     ])
@@ -184,6 +210,9 @@ fn run_worker(
         let events = wait_ctx.wait().map_err(ACPIPMError::WaitError)?;
         for event in events.iter().filter(|e| e.is_readable) {
             match event.token {
+                Token::AcpiEvent => {
+                    acpi_event_run(&acpi_event_sock, &gpe0, &sci_evt);
+                }
                 Token::InterruptResample => {
                     let _ = sci_resample.read();
 
@@ -215,6 +244,66 @@ fn run_worker(
     }
 }
 
+fn acpi_event_gpe_class(
+    gpe_number: u32,
+    _type: u32,
+    gpe0: &Arc<Mutex<GpeResource>>,
+    sci_evt: &Event,
+) {
+    // If gpe event, emulate GPE and trigger SCI
+    if _type == 0 && gpe_number < 256 {
+        let mut gpe0 = gpe0.lock();
+        let byte = gpe_number as usize / 8;
+
+        if byte >= gpe0.status.len() {
+            error!("gpe_evt: GPE register {} does not exist", byte);
+            return;
+        }
+        gpe0.status[byte] |= 1 << (gpe_number % 8);
+        gpe0.trigger_sci(sci_evt);
+    }
+}
+
+fn get_acpi_event_group() -> Option<u32> {
+    // Create netlink generic socket which will be used to query about given family name
+    let netlink_ctrl_sock = NetlinkGenericSocket::new(0).unwrap();
+
+    let nlmsg_family_response = netlink_ctrl_sock
+        .family_name_query("acpi_event".to_string())
+        .unwrap();
+    return nlmsg_family_response.get_multicast_group_id("acpi_mc_group".to_string());
+}
+
+fn acpi_event_run(
+    acpi_event_sock: &NetlinkGenericSocket,
+    gpe0: &Arc<Mutex<GpeResource>>,
+    sci_evt: &Event,
+) {
+    let nl_msg = match acpi_event_sock.recv() {
+        Ok(msg) => msg,
+        Err(e) => {
+            error!("recv returned with error {}", e);
+            return;
+        }
+    };
+
+    for netlink_message in nl_msg.iter() {
+        let acpi_event = match AcpiNotifyEvent::new(netlink_message) {
+            Ok(evt) => evt,
+            Err(e) => {
+                error!("Received netlink message is not an acpi_event, error {}", e);
+                continue;
+            }
+        };
+        match acpi_event.device_class.as_str() {
+            "gpe" => {
+                acpi_event_gpe_class(acpi_event.data, acpi_event._type, gpe0, sci_evt);
+            }
+            c => warn!("unknown acpi event {}", c),
+        };
+    }
+}
+
 impl Drop for ACPIPMResource {
     fn drop(&mut self) {
         if let Some(kill_evt) = self.kill_evt.take() {