move src/shared_rate_limiter.rs to src/tools/shared_rate_limiter.rs

Signed-off-by: Dietmar Maurer <dietmar@proxmox.com>

src/tools/mod.rs

@@ -16,6 +16,9 @@ pub mod apt;
 pub mod config;
 pub mod disks;
 
+mod shared_rate_limiter;
+pub use shared_rate_limiter::SharedRateLimiter;
+
 pub mod statistics;
 pub mod subscription;
 pub mod systemd;

src/tools/shared_rate_limiter.rs

@@ -0,0 +1,119 @@
+use std::path::PathBuf;
+use std::mem::MaybeUninit;
+use std::time::{Instant, Duration};
+
+use anyhow::{bail, Error};
+use nix::sys::stat::Mode;
+
+use proxmox_sys::fs::{create_path, CreateOptions};
+
+use proxmox_http::client::{RateLimit, RateLimiter, ShareableRateLimit};
+use proxmox_shared_memory::{Init, SharedMemory, SharedMutex};
+use proxmox_shared_memory::{check_subtype, initialize_subtype};
+
+// openssl::sha::sha256(b"Proxmox Backup SharedRateLimiter v1.0")[0..8];
+pub const PROXMOX_BACKUP_SHARED_RATE_LIMITER_MAGIC_1_0: [u8; 8] = [6, 58, 213, 96, 161, 122, 130, 117];
+
+const BASE_PATH: &str = pbs_buildcfg::rundir!("/shmem/tbf");
+
+// Wrap RateLimiter, so that we can provide an Init impl
+#[repr(C)]
+struct WrapLimiter(RateLimiter);
+
+impl Init for WrapLimiter {
+    fn initialize(this: &mut MaybeUninit<Self>) {
+        // default does not matter here, because we override later
+        this.write(WrapLimiter(RateLimiter::new(1_000_000, 1_000_000)));
+    }
+}
+
+#[repr(C)]
+struct SharedRateLimiterData {
+    magic: [u8; 8],
+    tbf: SharedMutex<WrapLimiter>,
+    padding: [u8; 4096 - 104],
+}
+
+impl Init for SharedRateLimiterData {
+    fn initialize(this: &mut MaybeUninit<Self>) {
+        unsafe {
+            let me = &mut *this.as_mut_ptr();
+            me.magic = PROXMOX_BACKUP_SHARED_RATE_LIMITER_MAGIC_1_0;
+            initialize_subtype(&mut me.tbf);
+        }
+    }
+
+    fn check_type_magic(this: &MaybeUninit<Self>) -> Result<(), Error> {
+        unsafe {
+            let me = &*this.as_ptr();
+            if me.magic != PROXMOX_BACKUP_SHARED_RATE_LIMITER_MAGIC_1_0 {
+                bail!("SharedRateLimiterData: wrong magic number");
+            }
+            check_subtype(&me.tbf)?;
+            Ok(())
+        }
+    }
+}
+
+/// Rate limiter designed for shared memory ([SharedMemory])
+///
+/// The actual [RateLimiter] is protected by a [SharedMutex] and
+/// implements [Init]. This way we can share the limiter between
+/// different processes.
+pub struct SharedRateLimiter {
+    shmem: SharedMemory<SharedRateLimiterData>
+}
+
+impl SharedRateLimiter {
+
+    /// Creates a new mmap'ed instance.
+    ///
+    /// Data is mapped in `/var/run/proxmox-backup/shmem/tbf/<name>` using
+    /// `TMPFS`.
+    pub fn mmap_shmem(name: &str, rate: u64, burst: u64) -> Result<Self, Error> {
+        let mut path = PathBuf::from(BASE_PATH);
+
+        let user = pbs_config::backup_user()?;
+
+        let dir_opts = CreateOptions::new()
+            .perm(Mode::from_bits_truncate(0o770))
+            .owner(user.uid)
+            .group(user.gid);
+
+        create_path(
+            &path,
+            Some(dir_opts.clone()),
+            Some(dir_opts))?;
+
+        path.push(name);
+
+        let file_opts = CreateOptions::new()
+            .perm(Mode::from_bits_truncate(0o660))
+            .owner(user.uid)
+            .group(user.gid);
+
+        let shmem: SharedMemory<SharedRateLimiterData> =
+            SharedMemory::open(&path, file_opts)?;
+
+        shmem.data().tbf.lock().0.update_rate(rate, burst);
+
+        Ok(Self { shmem })
+    }
+}
+
+impl ShareableRateLimit for SharedRateLimiter {
+    fn update_rate(&self, rate: u64, bucket_size: u64) {
+        self.shmem.data().tbf.lock().0
+            .update_rate(rate, bucket_size);
+    }
+
+    fn traffic(&self) -> u64 {
+        self.shmem.data().tbf.lock().0
+            .traffic()
+    }
+
+    fn register_traffic(&self, current_time: Instant, data_len: u64) -> Duration {
+        self.shmem.data().tbf.lock().0
+            .register_traffic(current_time, data_len)
+    }
+}