From 31e51ad2adb85698e70a2d64291d98bff7394b8d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E6=9C=9D=E5=80=89=E6=B0=B4=E5=B8=8C?=
 <asakuramizu111@gmail.com>
Date: Sun, 15 Feb 2026 22:59:23 +0800
Subject: [PATCH 1/2] refactor: merge starry-core & starry-api into
 starry-kernel

---
 Cargo.lock                                    |  82 ++----
 Cargo.toml                                    |  21 +-
 api/src/lib.rs                                |  35 ---
 api/src/signal.rs                             |  66 -----
 api/src/syscall/ipc/shm.rs                    | 228 ----------------
 api/src/task.rs                               | 220 ---------------
 core/Cargo.toml                               |  53 ----
 core/src/lib.rs                               |  20 --
 core/src/vfs/mod.rs                           |  40 ---
 {api => kernel}/Cargo.toml                    |  19 +-
 {core => kernel}/src/config/aarch64.rs        |   0
 {core => kernel}/src/config/loongarch64.rs    |   0
 {core => kernel}/src/config/mod.rs            |   0
 {core => kernel}/src/config/riscv64.rs        |   0
 {core => kernel}/src/config/x86_64.rs         |   0
 {api => kernel}/src/file/epoll.rs             |   0
 {api => kernel}/src/file/event.rs             |   0
 {api => kernel}/src/file/fs.rs                |   0
 {api => kernel}/src/file/mod.rs               |   2 +-
 {api => kernel}/src/file/net.rs               |   0
 {api => kernel}/src/file/pidfd.rs             |   3 +-
 {api => kernel}/src/file/pipe.rs              |   6 +-
 {api => kernel}/src/file/signalfd.rs          |   6 +-
 kernel/src/lib.rs                             |  30 +++
 api/src/mm.rs => kernel/src/mm/aspace.rs      |  70 ++++-
 {api/src => kernel/src/mm}/io.rs              |   0
 core/src/mm.rs => kernel/src/mm/loader.rs     |  76 +-----
 kernel/src/mm/mod.rs                          |   7 +
 .../vfs => kernel/src/pseudofs}/dev/event.rs  |   6 +-
 .../src/vfs => kernel/src/pseudofs}/dev/fb.rs |   3 +-
 .../vfs => kernel/src/pseudofs}/dev/log.rs    |   0
 .../vfs => kernel/src/pseudofs}/dev/loop.rs   |   6 +-
 .../src/pseudofs}/dev/memtrack.rs             |   6 +-
 .../vfs => kernel/src/pseudofs}/dev/mod.rs    |   5 +-
 .../vfs => kernel/src/pseudofs}/dev/rtc.rs    |   2 +-
 .../src/pseudofs/dev/tty/mod.rs               |  36 +--
 .../src/pseudofs}/dev/tty/ntty.rs             |   6 +-
 .../src/pseudofs}/dev/tty/ptm.rs              |   3 +-
 .../src/pseudofs}/dev/tty/pts.rs              |   3 +-
 .../src/pseudofs}/dev/tty/pty.rs              |  10 +-
 .../src/pseudofs/dev/tty}/terminal/job.rs     |   3 +-
 .../src/pseudofs/dev/tty}/terminal/ldisc.rs   |   4 +-
 .../src/pseudofs/dev/tty}/terminal/mod.rs     |   0
 .../src/pseudofs/dev/tty}/terminal/termios.rs |   2 +
 .../dev.rs => kernel/src/pseudofs/device.rs   |   0
 {core/src/vfs => kernel/src/pseudofs}/dir.rs  |   0
 {core/src/vfs => kernel/src/pseudofs}/file.rs |   0
 {core/src/vfs => kernel/src/pseudofs}/fs.rs   |   0
 {api/src/vfs => kernel/src/pseudofs}/mod.rs   |  39 ++-
 {api/src/vfs => kernel/src/pseudofs}/proc.rs  |  36 ++-
 {api/src/vfs => kernel/src/pseudofs}/tmp.rs   |   3 +-
 {api => kernel}/src/syscall/fs/ctl.rs         |   2 +-
 {api => kernel}/src/syscall/fs/event.rs       |   0
 {api => kernel}/src/syscall/fs/fd_ops.rs      |   4 +-
 {api => kernel}/src/syscall/fs/io.rs          |   3 +-
 {api => kernel}/src/syscall/fs/memfd.rs       |   0
 {api => kernel}/src/syscall/fs/mod.rs         |   0
 {api => kernel}/src/syscall/fs/mount.rs       |   2 +-
 {api => kernel}/src/syscall/fs/pidfd.rs       |   2 +-
 {api => kernel}/src/syscall/fs/pipe.rs        |   0
 {api => kernel}/src/syscall/fs/signalfd.rs    |   0
 {api => kernel}/src/syscall/fs/stat.rs        |   0
 {api => kernel}/src/syscall/io_mpx/epoll.rs   |   4 +-
 {api => kernel}/src/syscall/io_mpx/mod.rs     |   0
 {api => kernel}/src/syscall/io_mpx/poll.rs    |   4 +-
 {api => kernel}/src/syscall/io_mpx/select.rs  |   4 +-
 {api => kernel}/src/syscall/ipc/mod.rs        |  40 ++-
 {api => kernel}/src/syscall/ipc/msg.rs        |  13 +-
 {core/src => kernel/src/syscall/ipc}/shm.rs   | 254 +++++++++++++++---
 {api => kernel}/src/syscall/mm/brk.rs         |   3 +-
 {api => kernel}/src/syscall/mm/mincore.rs     |   3 +-
 {api => kernel}/src/syscall/mm/mmap.rs        |  10 +-
 {api => kernel}/src/syscall/mm/mod.rs         |   0
 {api => kernel}/src/syscall/mod.rs            |   2 +-
 .../src/syscall/net/addr.rs                   |   1 +
 {api => kernel}/src/syscall/net/cmsg.rs       |   0
 {api => kernel}/src/syscall/net/io.rs         |   5 +-
 {api => kernel}/src/syscall/net/mod.rs        |   1 +
 {api => kernel}/src/syscall/net/name.rs       |   2 +-
 {api => kernel}/src/syscall/net/opt.rs        |   0
 {api => kernel}/src/syscall/net/socket.rs     |   4 +-
 {api => kernel}/src/syscall/resources.rs      |   6 +-
 {api => kernel}/src/syscall/signal.rs         |   9 +-
 {api => kernel}/src/syscall/sync/futex.rs     |  16 +-
 .../src/syscall/sync/membarrier.rs            |   0
 {api => kernel}/src/syscall/sync/mod.rs       |   0
 {api => kernel}/src/syscall/sys.rs            |   3 +-
 {api => kernel}/src/syscall/task/clone.rs     |   7 +-
 {api => kernel}/src/syscall/task/ctl.rs       |   6 +-
 {api => kernel}/src/syscall/task/execve.rs    |   8 +-
 {api => kernel}/src/syscall/task/exit.rs      |   0
 {api => kernel}/src/syscall/task/job.rs       |   3 +-
 {api => kernel}/src/syscall/task/mod.rs       |   0
 {api => kernel}/src/syscall/task/schedule.rs  |   6 +-
 {api => kernel}/src/syscall/task/thread.rs    |   3 +-
 {api => kernel}/src/syscall/task/wait.rs      |   3 +-
 {api => kernel}/src/syscall/time.rs           |   6 +-
 {core/src => kernel/src/task}/futex.rs        |  44 ++-
 core/src/task.rs => kernel/src/task/mod.rs    | 246 +----------------
 kernel/src/task/ops.rs                        | 248 +++++++++++++++++
 {core/src => kernel/src/task}/resources.rs    |   0
 kernel/src/task/signal.rs                     | 138 ++++++++++
 {core => kernel}/src/task/stat.rs             |   0
 core/src/time.rs => kernel/src/task/timer.rs  |   0
 kernel/src/task/user.rs                       |  79 ++++++
 {api => kernel}/src/time.rs                   |  12 -
 src/entry.rs                                  |   9 +-
 src/main.rs                                   |   2 +-
 108 files changed, 1139 insertions(+), 1235 deletions(-)
 delete mode 100644 api/src/lib.rs
 delete mode 100644 api/src/signal.rs
 delete mode 100644 api/src/syscall/ipc/shm.rs
 delete mode 100644 api/src/task.rs
 delete mode 100644 core/Cargo.toml
 delete mode 100644 core/src/lib.rs
 delete mode 100644 core/src/vfs/mod.rs
 rename {api => kernel}/Cargo.toml (78%)
 rename {core => kernel}/src/config/aarch64.rs (100%)
 rename {core => kernel}/src/config/loongarch64.rs (100%)
 rename {core => kernel}/src/config/mod.rs (100%)
 rename {core => kernel}/src/config/riscv64.rs (100%)
 rename {core => kernel}/src/config/x86_64.rs (100%)
 rename {api => kernel}/src/file/epoll.rs (100%)
 rename {api => kernel}/src/file/event.rs (100%)
 rename {api => kernel}/src/file/fs.rs (100%)
 rename {api => kernel}/src/file/mod.rs (99%)
 rename {api => kernel}/src/file/net.rs (100%)
 rename {api => kernel}/src/file/pidfd.rs (94%)
 rename {api => kernel}/src/file/pipe.rs (98%)
 rename {api => kernel}/src/file/signalfd.rs (98%)
 create mode 100644 kernel/src/lib.rs
 rename api/src/mm.rs => kernel/src/mm/aspace.rs (82%)
 rename {api/src => kernel/src/mm}/io.rs (100%)
 rename core/src/mm.rs => kernel/src/mm/loader.rs (83%)
 create mode 100644 kernel/src/mm/mod.rs
 rename {api/src/vfs => kernel/src/pseudofs}/dev/event.rs (99%)
 rename {api/src/vfs => kernel/src/pseudofs}/dev/fb.rs (99%)
 rename {api/src/vfs => kernel/src/pseudofs}/dev/log.rs (100%)
 rename {api/src/vfs => kernel/src/pseudofs}/dev/loop.rs (98%)
 rename {api/src/vfs => kernel/src/pseudofs}/dev/memtrack.rs (99%)
 rename {api/src/vfs => kernel/src/pseudofs}/dev/mod.rs (97%)
 rename {api/src/vfs => kernel/src/pseudofs}/dev/rtc.rs (98%)
 rename api/src/vfs/dev/tty.rs => kernel/src/pseudofs/dev/tty/mod.rs (95%)
 rename {api/src/vfs => kernel/src/pseudofs}/dev/tty/ntty.rs (91%)
 rename {api/src/vfs => kernel/src/pseudofs}/dev/tty/ptm.rs (95%)
 rename {api/src/vfs => kernel/src/pseudofs}/dev/tty/pts.rs (93%)
 rename {api/src/vfs => kernel/src/pseudofs}/dev/tty/pty.rs (94%)
 rename {api/src => kernel/src/pseudofs/dev/tty}/terminal/job.rs (98%)
 rename {api/src => kernel/src/pseudofs/dev/tty}/terminal/ldisc.rs (99%)
 rename {api/src => kernel/src/pseudofs/dev/tty}/terminal/mod.rs (100%)
 rename {api/src => kernel/src/pseudofs/dev/tty}/terminal/termios.rs (99%)
 rename core/src/vfs/dev.rs => kernel/src/pseudofs/device.rs (100%)
 rename {core/src/vfs => kernel/src/pseudofs}/dir.rs (100%)
 rename {core/src/vfs => kernel/src/pseudofs}/file.rs (100%)
 rename {core/src/vfs => kernel/src/pseudofs}/fs.rs (100%)
 rename {api/src/vfs => kernel/src/pseudofs}/mod.rs (60%)
 rename {api/src/vfs => kernel/src/pseudofs}/proc.rs (96%)
 rename {api/src/vfs => kernel/src/pseudofs}/tmp.rs (99%)
 rename {api => kernel}/src/syscall/fs/ctl.rs (99%)
 rename {api => kernel}/src/syscall/fs/event.rs (100%)
 rename {api => kernel}/src/syscall/fs/fd_ops.rs (99%)
 rename {api => kernel}/src/syscall/fs/io.rs (99%)
 rename {api => kernel}/src/syscall/fs/memfd.rs (100%)
 rename {api => kernel}/src/syscall/fs/mod.rs (100%)
 rename {api => kernel}/src/syscall/fs/mount.rs (94%)
 rename {api => kernel}/src/syscall/fs/pidfd.rs (95%)
 rename {api => kernel}/src/syscall/fs/pipe.rs (100%)
 rename {api => kernel}/src/syscall/fs/signalfd.rs (100%)
 rename {api => kernel}/src/syscall/fs/stat.rs (100%)
 rename {api => kernel}/src/syscall/io_mpx/epoll.rs (98%)
 rename {api => kernel}/src/syscall/io_mpx/mod.rs (100%)
 rename {api => kernel}/src/syscall/io_mpx/poll.rs (97%)
 rename {api => kernel}/src/syscall/io_mpx/select.rs (98%)
 rename {api => kernel}/src/syscall/ipc/mod.rs (59%)
 rename {api => kernel}/src/syscall/ipc/msg.rs (99%)
 rename {core/src => kernel/src/syscall/ipc}/shm.rs (59%)
 rename {api => kernel}/src/syscall/mm/brk.rs (99%)
 rename {api => kernel}/src/syscall/mm/mincore.rs (99%)
 rename {api => kernel}/src/syscall/mm/mmap.rs (99%)
 rename {api => kernel}/src/syscall/mm/mod.rs (100%)
 rename {api => kernel}/src/syscall/mod.rs (99%)
 rename api/src/socket.rs => kernel/src/syscall/net/addr.rs (99%)
 rename {api => kernel}/src/syscall/net/cmsg.rs (100%)
 rename {api => kernel}/src/syscall/net/io.rs (97%)
 rename {api => kernel}/src/syscall/net/mod.rs (91%)
 rename {api => kernel}/src/syscall/net/name.rs (96%)
 rename {api => kernel}/src/syscall/net/opt.rs (100%)
 rename {api => kernel}/src/syscall/net/socket.rs (98%)
 rename {api => kernel}/src/syscall/resources.rs (97%)
 rename {api => kernel}/src/syscall/signal.rs (97%)
 rename {api => kernel}/src/syscall/sync/futex.rs (92%)
 rename {api => kernel}/src/syscall/sync/membarrier.rs (100%)
 rename {api => kernel}/src/syscall/sync/mod.rs (100%)
 rename {api => kernel}/src/syscall/sys.rs (98%)
 rename {api => kernel}/src/syscall/task/clone.rs (98%)
 rename {api => kernel}/src/syscall/task/ctl.rs (97%)
 rename {api => kernel}/src/syscall/task/execve.rs (94%)
 rename {api => kernel}/src/syscall/task/exit.rs (100%)
 rename {api => kernel}/src/syscall/task/job.rs (93%)
 rename {api => kernel}/src/syscall/task/mod.rs (100%)
 rename {api => kernel}/src/syscall/task/schedule.rs (97%)
 rename {api => kernel}/src/syscall/task/thread.rs (98%)
 rename {api => kernel}/src/syscall/task/wait.rs (99%)
 rename {api => kernel}/src/syscall/time.rs (97%)
 rename {core/src => kernel/src/task}/futex.rs (83%)
 rename core/src/task.rs => kernel/src/task/mod.rs (52%)
 create mode 100644 kernel/src/task/ops.rs
 rename {core/src => kernel/src/task}/resources.rs (100%)
 create mode 100644 kernel/src/task/signal.rs
 rename {core => kernel}/src/task/stat.rs (100%)
 rename core/src/time.rs => kernel/src/task/timer.rs (100%)
 create mode 100644 kernel/src/task/user.rs
 rename {api => kernel}/src/time.rs (93%)

diff --git a/Cargo.lock b/Cargo.lock
index a530567c..5c93b6fd 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -18,7 +18,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1b5d307320b3181d6d7954e663bd7c774a838b8220fe0593c86d9fb09f498b4b"
 dependencies = [
  "cpp_demangle",
- "gimli 0.32.3",
+ "gimli",
  "rustc-demangle",
 ]
 
@@ -195,7 +195,7 @@ checksum = "bf9566516f5d799b2f791a6ec5af57eec87d17624346f7c876fa006b922c99e6"
 dependencies = [
  "addr2line",
  "cfg-if",
- "gimli 0.32.3",
+ "gimli",
  "log",
  "paste",
  "spin 0.10.0",
@@ -1328,12 +1328,6 @@ dependencies = [
  "stable_deref_trait",
 ]
 
-[[package]]
-name = "gimli"
-version = "0.33.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0bf7f043f89559805f8c7cacc432749b2fa0d0a0a9ee46ce47164ed5ba7f126c"
-
 [[package]]
 name = "glob"
 version = "0.3.3"
@@ -2189,30 +2183,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6ce2be8dc25455e1f91df71bfa12ad37d7af1092ae736f3a6cd0e37bc7810596"
 
 [[package]]
-name = "starry"
-version = "0.1.0"
-dependencies = [
- "axdriver",
- "axerrno 0.2.2",
- "axfeat",
- "axfs",
- "axhal",
- "axlog",
- "axplat-riscv64-visionfive2",
- "axruntime",
- "axsync",
- "axtask",
- "cfg-if",
- "linkme",
- "linux-raw-sys",
- "starry-api",
- "starry-core",
- "starry-process",
- "starry-signal",
-]
-
-[[package]]
-name = "starry-api"
+name = "starry-kernel"
 version = "0.1.0"
 dependencies = [
  "axalloc",
@@ -2240,76 +2211,61 @@ dependencies = [
  "chrono",
  "downcast-rs",
  "event-listener",
+ "extern-trait",
  "flatten_objects",
- "gimli 0.33.0",
+ "gimli",
  "hashbrown 0.16.1",
  "indoc",
  "inherit-methods-macro",
+ "kernel-elf-parser",
+ "kernel_guard",
  "kspin",
  "lazy_static",
  "linkme",
  "linux-raw-sys",
+ "lock_api",
  "memory_addr",
  "num_enum",
+ "ouroboros",
+ "percpu",
  "rand",
  "ringbuf",
  "riscv 0.16.0",
  "scope-local",
  "slab",
  "spin 0.10.0",
- "starry-core",
  "starry-process",
  "starry-signal",
  "starry-vm",
+ "strum",
  "syscalls",
+ "uluru",
+ "weak-map",
  "x86",
+ "xmas-elf",
  "zerocopy 0.8.39",
 ]
 
 [[package]]
-name = "starry-core"
+name = "starry-main"
 version = "0.1.0"
 dependencies = [
- "axbacktrace",
- "axconfig",
+ "axdriver",
  "axerrno 0.2.2",
  "axfeat",
  "axfs",
- "axfs-ng-vfs",
  "axhal",
- "axio",
  "axlog",
- "axmm",
- "axpoll",
+ "axplat-riscv64-visionfive2",
+ "axruntime",
  "axsync",
  "axtask",
- "bitflags 2.10.0",
- "bytemuck",
  "cfg-if",
- "event-listener",
- "extern-trait",
- "hashbrown 0.16.1",
- "inherit-methods-macro",
- "kernel-elf-parser",
- "kernel_guard",
- "kspin",
- "lazy_static",
  "linkme",
  "linux-raw-sys",
- "lock_api",
- "memory_addr",
- "ouroboros",
- "percpu",
- "scope-local",
- "slab",
- "spin 0.10.0",
+ "starry-kernel",
  "starry-process",
  "starry-signal",
- "starry-vm",
- "strum",
- "uluru",
- "weak-map",
- "xmas-elf",
 ]
 
 [[package]]
diff --git a/Cargo.toml b/Cargo.toml
index c04695bb..f38bb280 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [workspace]
 resolver = "2"
-members = ["api", "core"]
+members = ["kernel"]
 exclude = ["arceos"]
 
 [workspace.package]
@@ -15,8 +15,8 @@ authors = [
     "朝倉水希 <asakuramizu111@gmail.com>",
     "Mivik <mivikq@gmail.com>",
 ]
-homepage = "https://github.com/arceos-org/arceos"
-repository = "https://github.com/arceos-org/starry-next"
+homepage = "https://github.com/Starry-OS"
+repository = "https://github.com/Starry-OS/StarryOS"
 
 [workspace.dependencies]
 axfeat = { path = "arceos/api/axfeat", features = [
@@ -76,11 +76,10 @@ starry-process = "0.2"
 starry-signal = "0.3"
 starry-vm = "0.3"
 
-starry-core = { path = "./core" }
-starry-api = { path = "./api" }
+starry-kernel = { path = "./kernel" }
 
 [package]
-name = "starry"
+name = "starry-main"
 version.workspace = true
 edition.workspace = true
 authors.workspace = true
@@ -93,17 +92,17 @@ default = []
 qemu = [
     "axfeat/display",
     "axfeat/input",
-    "starry-api/input",
+    "starry-kernel/input",
 
     "axfeat/vsock",
-    "starry-api/vsock",
+    "starry-kernel/vsock",
 
     "axfeat/defplat",
     "axfeat/bus-pci",
 
     # auxilary features
     "axfeat/fs-times",
-    "starry-api/dev-log",
+    "starry-kernel/dev-log",
 ]
 smp = ["axfeat/smp", "axplat-riscv64-visionfive2?/smp"]
 
@@ -122,12 +121,10 @@ axtask.workspace = true
 cfg-if.workspace = true
 linkme.workspace = true
 linux-raw-sys.workspace = true
+starry-kernel.workspace = true
 starry-process.workspace = true
 starry-signal.workspace = true
 
-starry-core.workspace = true
-starry-api.workspace = true
-
 [dependencies.axplat-riscv64-visionfive2]
 version = "0.1.0-pre.1"
 features = ["fp-simd", "irq", "rtc"]
diff --git a/api/src/lib.rs b/api/src/lib.rs
deleted file mode 100644
index e6ec362e..00000000
--- a/api/src/lib.rs
+++ /dev/null
@@ -1,35 +0,0 @@
-#![no_std]
-#![feature(likely_unlikely)]
-#![feature(bstr)]
-#![allow(missing_docs)]
-#![allow(clippy::not_unsafe_ptr_arg_deref)]
-
-#[macro_use]
-extern crate axlog;
-
-extern crate alloc;
-
-pub mod file;
-pub mod io;
-pub mod mm;
-pub mod signal;
-pub mod socket;
-pub mod syscall;
-pub mod task;
-pub mod terminal;
-pub mod time;
-pub mod vfs;
-
-/// Initialize.
-pub fn init() {
-    info!("Initialize VFS...");
-    vfs::mount_all().expect("Failed to mount vfs");
-
-    info!("Initialize /proc/interrupts...");
-    axtask::register_timer_callback(|_| {
-        time::inc_irq_cnt();
-    });
-
-    info!("Initialize alarm...");
-    starry_core::time::spawn_alarm_task();
-}
diff --git a/api/src/signal.rs b/api/src/signal.rs
deleted file mode 100644
index 9aa064cb..00000000
--- a/api/src/signal.rs
+++ /dev/null
@@ -1,66 +0,0 @@
-use core::sync::atomic::{AtomicBool, Ordering};
-
-use axerrno::AxResult;
-use axhal::uspace::UserContext;
-use axtask::current;
-use starry_core::task::{AsThread, Thread};
-use starry_signal::{SignalOSAction, SignalSet};
-
-use crate::task::do_exit;
-
-pub fn check_signals(
-    thr: &Thread,
-    uctx: &mut UserContext,
-    restore_blocked: Option<SignalSet>,
-) -> bool {
-    let Some((sig, os_action)) = thr.signal.check_signals(uctx, restore_blocked) else {
-        return false;
-    };
-
-    let signo = sig.signo();
-    match os_action {
-        SignalOSAction::Terminate => {
-            do_exit(signo as i32, true);
-        }
-        SignalOSAction::CoreDump => {
-            // TODO: implement core dump
-            do_exit(128 + signo as i32, true);
-        }
-        SignalOSAction::Stop => {
-            // TODO: implement stop
-            do_exit(1, true);
-        }
-        SignalOSAction::Continue => {
-            // TODO: implement continue
-        }
-        SignalOSAction::Handler => {
-            // do nothing
-        }
-    }
-    true
-}
-
-static BLOCK_NEXT_SIGNAL_CHECK: AtomicBool = AtomicBool::new(false);
-
-pub fn block_next_signal() {
-    BLOCK_NEXT_SIGNAL_CHECK.store(true, Ordering::SeqCst);
-}
-
-pub fn unblock_next_signal() -> bool {
-    BLOCK_NEXT_SIGNAL_CHECK.swap(false, Ordering::SeqCst)
-}
-
-pub fn with_replacen_blocked<R>(
-    blocked: Option<SignalSet>,
-    f: impl FnOnce() -> AxResult<R>,
-) -> AxResult<R> {
-    let curr = current();
-    let sig = &curr.as_thread().signal;
-
-    let old_blocked = blocked.map(|set| sig.set_blocked(set));
-    f().inspect(|_| {
-        if let Some(old) = old_blocked {
-            sig.set_blocked(old);
-        }
-    })
-}
diff --git a/api/src/syscall/ipc/shm.rs b/api/src/syscall/ipc/shm.rs
deleted file mode 100644
index 936d6880..00000000
--- a/api/src/syscall/ipc/shm.rs
+++ /dev/null
@@ -1,228 +0,0 @@
-use alloc::sync::Arc;
-
-use axerrno::{AxError, AxResult};
-use axhal::{
-    paging::{MappingFlags, PageSize},
-    time::monotonic_time_nanos,
-};
-use axmm::backend::{Backend, SharedPages};
-use axsync::Mutex;
-use axtask::current;
-use linux_raw_sys::general::*;
-use memory_addr::{PAGE_SIZE_4K, VirtAddr, VirtAddrRange};
-use starry_core::{
-    shm::{SHM_MANAGER, ShmInner, ShmidDs},
-    task::AsThread,
-};
-
-use super::{IPC_PRIVATE, IPC_RMID, IPC_SET, IPC_STAT, next_ipc_id};
-use crate::mm::{UserPtr, nullable};
-
-bitflags::bitflags! {
-    /// flags for sys_shmat
-    #[derive(Debug)]
-    struct ShmAtFlags: u32 {
-        /* attach read-only else read-write */
-        const SHM_RDONLY = 0o10000;
-        /* round attach address to SHMLBA */
-        const SHM_RND = 0o20000;
-        /* take-over region on attach */
-        const SHM_REMAP = 0o40000;
-    }
-}
-
-pub fn sys_shmget(key: i32, size: usize, shmflg: usize) -> AxResult<isize> {
-    let page_num = memory_addr::align_up_4k(size) / PAGE_SIZE_4K;
-    if page_num == 0 {
-        return Err(AxError::InvalidInput);
-    }
-
-    let mut mapping_flags = MappingFlags::from_name("USER").unwrap();
-    if shmflg & 0o400 != 0 {
-        mapping_flags.insert(MappingFlags::READ);
-    }
-    if shmflg & 0o200 != 0 {
-        mapping_flags.insert(MappingFlags::WRITE);
-    }
-    if shmflg & 0o100 != 0 {
-        mapping_flags.insert(MappingFlags::EXECUTE);
-    }
-
-    let cur_pid = current().as_thread().proc_data.proc.pid();
-    let mut shm_manager = SHM_MANAGER.lock();
-
-    if key != IPC_PRIVATE {
-        // This process has already created a shared memory segment with the same key
-        if let Some(shmid) = shm_manager.get_shmid_by_key(key) {
-            let shm_inner = shm_manager
-                .get_inner_by_shmid(shmid)
-                .ok_or(AxError::InvalidInput)?;
-            let mut shm_inner = shm_inner.lock();
-            return shm_inner.try_update(size, mapping_flags, cur_pid);
-        }
-    }
-
-    // Create a new shm_inner
-    let shmid = next_ipc_id();
-    let shm_inner = Arc::new(Mutex::new(ShmInner::new(
-        key,
-        shmid,
-        size,
-        mapping_flags,
-        cur_pid,
-    )));
-    shm_manager.insert_key_shmid(key, shmid);
-    shm_manager.insert_shmid_inner(shmid, shm_inner);
-
-    Ok(shmid as isize)
-}
-
-pub fn sys_shmat(shmid: i32, addr: usize, shmflg: u32) -> AxResult<isize> {
-    let shm_inner = {
-        let shm_manager = SHM_MANAGER.lock();
-        shm_manager.get_inner_by_shmid(shmid).unwrap()
-    };
-    let mut shm_inner = shm_inner.lock();
-    let mut mapping_flags = shm_inner.mapping_flags;
-    let shm_flg = ShmAtFlags::from_bits_truncate(shmflg);
-
-    if shm_flg.contains(ShmAtFlags::SHM_RDONLY) {
-        mapping_flags.remove(MappingFlags::WRITE);
-    }
-
-    // TODO: solve shmflg: SHM_RND and SHM_REMAP
-
-    let curr = current();
-    let proc_data = &curr.as_thread().proc_data;
-    let pid = proc_data.proc.pid();
-    let mut aspace = proc_data.aspace.lock();
-
-    let start_aligned = memory_addr::align_down_4k(addr);
-    let length = shm_inner.page_num * PAGE_SIZE_4K;
-
-    // alloc the virtual address range
-    assert!(shm_inner.get_addr_range(pid).is_none());
-    let start_addr = aspace
-        .find_free_area(
-            VirtAddr::from(start_aligned),
-            length,
-            VirtAddrRange::new(aspace.base(), aspace.end()),
-            PAGE_SIZE_4K,
-        )
-        .or_else(|| {
-            aspace.find_free_area(
-                aspace.base(),
-                length,
-                VirtAddrRange::new(aspace.base(), aspace.end()),
-                PAGE_SIZE_4K,
-            )
-        })
-        .ok_or(AxError::NoMemory)?;
-    let end_addr = VirtAddr::from(start_addr.as_usize() + length);
-    let va_range = VirtAddrRange::new(start_addr, end_addr);
-
-    let mut shm_manager = SHM_MANAGER.lock();
-    shm_manager.insert_shmid_vaddr(pid, shm_inner.shmid, start_addr);
-    info!(
-        "Process {} alloc shm virt addr start: {:#x}, size: {}, mapping_flags: {:#x?}",
-        pid,
-        start_addr.as_usize(),
-        length,
-        mapping_flags
-    );
-
-    // map the virtual address range to the physical address
-    if let Some(phys_pages) = shm_inner.phys_pages.clone() {
-        // Another proccess has attached the shared memory
-        // TODO(mivik): shm page size
-        let backend = Backend::new_shared(start_addr, phys_pages);
-        aspace.map(start_addr, length, mapping_flags, false, backend)?;
-    } else {
-        // This is the first process to attach the shared memory
-        let pages = Arc::new(SharedPages::new(length, PageSize::Size4K)?);
-        let backend = Backend::new_shared(start_addr, pages.clone());
-        aspace.map(start_addr, length, mapping_flags, false, backend)?;
-
-        shm_inner.map_to_phys(pages);
-    }
-
-    shm_inner.attach_process(pid, va_range);
-    Ok(start_addr.as_usize() as isize)
-}
-
-pub fn sys_shmctl(shmid: i32, cmd: u32, buf: UserPtr<ShmidDs>) -> AxResult<isize> {
-    let shm_inner = {
-        let shm_manager = SHM_MANAGER.lock();
-        shm_manager
-            .get_inner_by_shmid(shmid)
-            .ok_or(AxError::InvalidInput)?
-    };
-    let mut shm_inner = shm_inner.lock();
-
-    let cmd = cmd as i32;
-    if cmd == IPC_SET {
-        shm_inner.shmid_ds = *buf.get_as_mut()?;
-    } else if cmd == IPC_STAT {
-        if let Some(shmid_ds) = nullable!(buf.get_as_mut())? {
-            *shmid_ds = shm_inner.shmid_ds;
-        }
-    } else if cmd == IPC_RMID {
-        shm_inner.rmid = true;
-    } else {
-        return Err(AxError::InvalidInput);
-    }
-
-    shm_inner.shmid_ds.shm_ctime = monotonic_time_nanos() as __kernel_time_t;
-    Ok(0)
-}
-
-// Garbage collection for shared memory:
-// 1. when the process call sys_shmdt, delete everything related to shmaddr,
-//    including map 'shmid_vaddr';
-// 2. when the last process detach the shared memory and this shared memory was
-//    specified with IPC_RMID, delete everything related to this shared memory,
-//    including all the 3 maps;
-// 3. when a process exit, delete everything related to this process, including
-//    2 maps: 'shmid_vaddr' and 'shmid_inner';
-//
-// The attach between the process and the shared memory occurs in sys_shmat,
-//  and the detach occurs in sys_shmdt, or when the process exits.
-
-// Note: all the below delete functions only delete the mapping between the
-// shm_id and the shm_inner,   but the shm_inner is not deleted or modifyed!
-pub fn sys_shmdt(shmaddr: usize) -> AxResult<isize> {
-    let shmaddr = VirtAddr::from(shmaddr);
-
-    let curr = current();
-    let proc_data = &curr.as_thread().proc_data;
-
-    let pid = proc_data.proc.pid();
-    let shmid = {
-        let shm_manager = SHM_MANAGER.lock();
-        shm_manager
-            .get_shmid_by_vaddr(pid, shmaddr)
-            .ok_or(AxError::InvalidInput)?
-    };
-
-    let shm_inner = {
-        let shm_manager = SHM_MANAGER.lock();
-        shm_manager
-            .get_inner_by_shmid(shmid)
-            .ok_or(AxError::InvalidInput)?
-    };
-    let mut shm_inner = shm_inner.lock();
-    let va_range = shm_inner.get_addr_range(pid).ok_or(AxError::InvalidInput)?;
-
-    let mut aspace = proc_data.aspace.lock();
-    aspace.unmap(va_range.start, va_range.size())?;
-
-    let mut shm_manager = SHM_MANAGER.lock();
-    shm_manager.remove_shmaddr(pid, shmaddr);
-    shm_inner.detach_process(pid);
-
-    if shm_inner.rmid && shm_inner.attach_count() == 0 {
-        shm_manager.remove_shmid(shmid);
-    }
-
-    Ok(0)
-}
diff --git a/api/src/task.rs b/api/src/task.rs
deleted file mode 100644
index aaadb6c3..00000000
--- a/api/src/task.rs
+++ /dev/null
@@ -1,220 +0,0 @@
-use core::{ffi::c_long, sync::atomic::Ordering};
-
-use axerrno::{AxError, AxResult};
-use axhal::uspace::{ExceptionKind, ReturnReason, UserContext};
-use axtask::{TaskInner, current};
-use bytemuck::AnyBitPattern;
-use linux_raw_sys::general::ROBUST_LIST_LIMIT;
-use starry_core::{
-    futex::FutexKey,
-    shm::SHM_MANAGER,
-    task::{
-        AsThread, get_process_data, get_task, send_signal_to_process, send_signal_to_thread,
-        set_timer_state,
-    },
-    time::TimerState,
-};
-use starry_process::Pid;
-use starry_signal::{SignalInfo, Signo};
-use starry_vm::{VmMutPtr, VmPtr};
-
-use crate::{
-    signal::{check_signals, unblock_next_signal},
-    syscall::handle_syscall,
-};
-
-/// Create a new user task.
-pub fn new_user_task(name: &str, mut uctx: UserContext, set_child_tid: usize) -> TaskInner {
-    TaskInner::new(
-        move || {
-            let curr = axtask::current();
-
-            if let Some(tid) = (set_child_tid as *mut Pid).nullable() {
-                tid.vm_write(curr.id().as_u64() as Pid).ok();
-            }
-
-            info!("Enter user space: ip={:#x}, sp={:#x}", uctx.ip(), uctx.sp());
-
-            let thr = curr.as_thread();
-            while !thr.pending_exit() {
-                let reason = uctx.run();
-
-                set_timer_state(&curr, TimerState::Kernel);
-
-                match reason {
-                    ReturnReason::Syscall => handle_syscall(&mut uctx),
-                    ReturnReason::PageFault(addr, flags) => {
-                        if !thr.proc_data.aspace.lock().handle_page_fault(addr, flags) {
-                            info!(
-                                "{:?}: segmentation fault at {:#x} {:?}",
-                                thr.proc_data.proc, addr, flags
-                            );
-                            raise_signal_fatal(SignalInfo::new_kernel(Signo::SIGSEGV))
-                                .expect("Failed to send SIGSEGV");
-                        }
-                    }
-                    ReturnReason::Interrupt => {}
-                    #[allow(unused_labels)]
-                    ReturnReason::Exception(exc_info) => 'exc: {
-                        // TODO: detailed handling
-                        let signo = match exc_info.kind() {
-                            ExceptionKind::Misaligned => {
-                                #[cfg(target_arch = "loongarch64")]
-                                if unsafe { uctx.emulate_unaligned() }.is_ok() {
-                                    break 'exc;
-                                }
-                                Signo::SIGBUS
-                            }
-                            ExceptionKind::Breakpoint => Signo::SIGTRAP,
-                            ExceptionKind::IllegalInstruction => Signo::SIGILL,
-                            _ => Signo::SIGTRAP,
-                        };
-                        raise_signal_fatal(SignalInfo::new_kernel(signo))
-                            .expect("Failed to send SIGTRAP");
-                    }
-                    r => {
-                        warn!("Unexpected return reason: {r:?}");
-                        raise_signal_fatal(SignalInfo::new_kernel(Signo::SIGSEGV))
-                            .expect("Failed to send SIGSEGV");
-                    }
-                }
-
-                if !unblock_next_signal() {
-                    while check_signals(thr, &mut uctx, None) {}
-                }
-
-                set_timer_state(&curr, TimerState::User);
-                curr.clear_interrupt();
-            }
-        },
-        name.into(),
-        starry_core::config::KERNEL_STACK_SIZE,
-    )
-}
-
-#[repr(C)]
-#[derive(Debug, Copy, Clone, AnyBitPattern)]
-pub struct RobustList {
-    pub next: *mut RobustList,
-}
-
-#[repr(C)]
-#[derive(Debug, Copy, Clone, AnyBitPattern)]
-pub struct RobustListHead {
-    pub list: RobustList,
-    pub futex_offset: c_long,
-    pub list_op_pending: *mut RobustList,
-}
-
-fn handle_futex_death(entry: *mut RobustList, offset: i64) -> AxResult<()> {
-    let address = (entry as u64)
-        .checked_add_signed(offset)
-        .ok_or(AxError::InvalidInput)?;
-    let address: usize = address.try_into().map_err(|_| AxError::InvalidInput)?;
-    let key = FutexKey::new_current(address);
-
-    let curr = current();
-    let futex_table = curr.as_thread().proc_data.futex_table_for(&key);
-
-    let Some(futex) = futex_table.get(&key) else {
-        return Ok(());
-    };
-    futex.owner_dead.store(true, Ordering::SeqCst);
-    futex.wq.wake(1, u32::MAX);
-    Ok(())
-}
-
-pub fn exit_robust_list(head: *const RobustListHead) -> AxResult<()> {
-    // Reference: https://elixir.bootlin.com/linux/v6.13.6/source/kernel/futex/core.c#L777
-
-    let mut limit = ROBUST_LIST_LIMIT;
-
-    let end_ptr = unsafe { &raw const (*head).list };
-    let head = head.vm_read()?;
-    let mut entry = head.list.next;
-    let offset = head.futex_offset;
-    let pending = head.list_op_pending;
-
-    while !core::ptr::eq(entry, end_ptr) {
-        let next_entry = entry.vm_read()?.next;
-        if entry != pending {
-            handle_futex_death(entry, offset)?;
-        }
-        entry = next_entry;
-
-        limit -= 1;
-        if limit == 0 {
-            return Err(AxError::FilesystemLoop);
-        }
-        axtask::yield_now();
-    }
-
-    Ok(())
-}
-
-pub fn do_exit(exit_code: i32, group_exit: bool) {
-    let curr = current();
-    let thr = curr.as_thread();
-
-    info!("{} exit with code: {}", curr.id_name(), exit_code);
-
-    let clear_child_tid = thr.clear_child_tid() as *mut u32;
-    if clear_child_tid.vm_write(0).is_ok() {
-        let key = FutexKey::new_current(clear_child_tid as usize);
-        let table = thr.proc_data.futex_table_for(&key);
-        let guard = table.get(&key);
-        if let Some(futex) = guard {
-            futex.wq.wake(1, u32::MAX);
-        }
-        axtask::yield_now();
-    }
-    let head = thr.robust_list_head() as *const RobustListHead;
-    if !head.is_null()
-        && let Err(err) = exit_robust_list(head)
-    {
-        warn!("exit robust list failed: {err:?}");
-    }
-
-    let process = &thr.proc_data.proc;
-    if process.exit_thread(curr.id().as_u64() as Pid, exit_code) {
-        process.exit();
-        if let Some(parent) = process.parent() {
-            if let Some(signo) = thr.proc_data.exit_signal {
-                let _ = send_signal_to_process(parent.pid(), Some(SignalInfo::new_kernel(signo)));
-            }
-            if let Ok(data) = get_process_data(parent.pid()) {
-                data.child_exit_event.wake();
-            }
-        }
-        thr.proc_data.exit_event.wake();
-
-        SHM_MANAGER.lock().clear_proc_shm(process.pid());
-    }
-    if group_exit && !process.is_group_exited() {
-        process.group_exit();
-        let sig = SignalInfo::new_kernel(Signo::SIGKILL);
-        for tid in process.threads() {
-            let _ = send_signal_to_thread(None, tid, Some(sig.clone()));
-        }
-    }
-    thr.set_exit();
-}
-
-/// Sends a fatal signal to the current process.
-pub fn raise_signal_fatal(sig: SignalInfo) -> AxResult<()> {
-    let curr = current();
-    let proc_data = &curr.as_thread().proc_data;
-
-    let signo = sig.signo();
-    info!("Send fatal signal {signo:?} to the current process");
-    if let Some(tid) = proc_data.signal.send_signal(sig)
-        && let Ok(task) = get_task(tid)
-    {
-        task.interrupt();
-    } else {
-        // No task wants to handle the signal, abort the task
-        do_exit(signo as i32, true);
-    }
-
-    Ok(())
-}
diff --git a/core/Cargo.toml b/core/Cargo.toml
deleted file mode 100644
index a4beff17..00000000
--- a/core/Cargo.toml
+++ /dev/null
@@ -1,53 +0,0 @@
-[package]
-name = "starry-core"
-version.workspace = true
-edition.workspace = true
-authors.workspace = true
-license.workspace = true
-homepage.workspace = true
-repository.workspace = true
-
-[dependencies]
-axbacktrace.workspace = true
-axconfig.workspace = true
-axerrno.workspace = true
-axfeat.workspace = true
-axfs-ng-vfs.workspace = true
-axfs.workspace = true
-axhal.workspace = true
-axio.workspace = true
-axlog.workspace = true
-axmm.workspace = true
-axpoll.workspace = true
-axsync.workspace = true
-axtask.workspace = true
-bitflags.workspace = true
-bytemuck = { workspace = true, features = ["derive"] }
-cfg-if.workspace = true
-event-listener.workspace = true
-extern-trait.workspace = true
-hashbrown = { workspace = true }
-inherit-methods-macro = "0.1.0"
-kernel_guard = "0.1"
-kernel-elf-parser = "0.3.4"
-kspin.workspace = true
-lazy_static = { workspace = true }
-linkme.workspace = true
-linux-raw-sys.workspace = true
-lock_api = { version = "0.4.13", features = ["arc_lock"] }
-memory_addr.workspace = true
-ouroboros = { version = "0.18.5", default-features = false }
-percpu = "0.2.0"
-scope-local.workspace = true
-slab.workspace = true
-spin.workspace = true
-starry-process.workspace = true
-starry-signal.workspace = true
-starry-vm.workspace = true
-strum = { version = "0.27.2", default-features = false, features = ["derive"] }
-uluru = "3.1.0"
-weak-map = "0.1.1"
-xmas-elf = "0.9"
-
-[target.'cfg(not(any(target_arch = "aarch64", target_arch = "loongarch64")))'.dependencies]
-axmm = { workspace = true, features = ["copy"] }
diff --git a/core/src/lib.rs b/core/src/lib.rs
deleted file mode 100644
index c4e8e09c..00000000
--- a/core/src/lib.rs
+++ /dev/null
@@ -1,20 +0,0 @@
-//! The core functionality of a monolithic kernel, including loading user
-//! programs and managing processes.
-
-#![no_std]
-#![feature(likely_unlikely)]
-#![warn(missing_docs)]
-
-extern crate alloc;
-
-#[macro_use]
-extern crate axlog;
-
-pub mod config;
-pub mod futex;
-pub mod mm;
-pub mod resources;
-pub mod shm;
-pub mod task;
-pub mod time;
-pub mod vfs;
diff --git a/core/src/vfs/mod.rs b/core/src/vfs/mod.rs
deleted file mode 100644
index ce3557ab..00000000
--- a/core/src/vfs/mod.rs
+++ /dev/null
@@ -1,40 +0,0 @@
-//! Basic virtual filesystem support
-
-mod dev;
-mod dir;
-mod file;
-mod fs;
-
-use alloc::sync::Arc;
-
-use axfs_ng_vfs::{DirNodeOps, FileNodeOps, WeakDirEntry};
-pub use dev::*;
-pub use dir::*;
-pub use file::*;
-pub use fs::*;
-
-/// A callback that builds a `Arc<dyn DirNodeOps>` for a given
-/// `WeakDirEntry`.
-pub type DirMaker = Arc<dyn Fn(WeakDirEntry) -> Arc<dyn DirNodeOps> + Send + Sync>;
-
-/// An enum containing either a directory ([`DirMaker`]) or a file (`Arc<dyn
-/// FileNodeOps>`).
-#[derive(Clone)]
-pub enum NodeOpsMux {
-    /// A directory node.
-    Dir(DirMaker),
-    /// A file node.
-    File(Arc<dyn FileNodeOps>),
-}
-
-impl From<DirMaker> for NodeOpsMux {
-    fn from(maker: DirMaker) -> Self {
-        Self::Dir(maker)
-    }
-}
-
-impl<T: FileNodeOps> From<Arc<T>> for NodeOpsMux {
-    fn from(ops: Arc<T>) -> Self {
-        Self::File(ops)
-    }
-}
diff --git a/api/Cargo.toml b/kernel/Cargo.toml
similarity index 78%
rename from api/Cargo.toml
rename to kernel/Cargo.toml
index 73fa91ef..7e410ec2 100644
--- a/api/Cargo.toml
+++ b/kernel/Cargo.toml
@@ -1,5 +1,5 @@
 [package]
-name = "starry-api"
+name = "starry-kernel"
 version.workspace = true
 edition.workspace = true
 authors.workspace = true
@@ -34,22 +34,28 @@ axsync.workspace = true
 axtask.workspace = true
 bitflags.workspace = true
 bitmaps = { version = "3.2.1", default-features = false }
-bytemuck.workspace = true
+bytemuck = { workspace = true, features = ["derive"] }
 cfg-if.workspace = true
 chrono = { version = "0.4.41", default-features = false }
 downcast-rs = { version = "2.0", default-features = false, features = ["sync"] }
 event-listener.workspace = true
+extern-trait.workspace = true
 flatten_objects = "0.2.4"
 gimli = { version = "*", default-features = false, optional = true }
 hashbrown = { workspace = true }
 indoc = "2"
 inherit-methods-macro = "0.1.0"
+kernel_guard = "0.1"
+kernel-elf-parser = "0.3.4"
 kspin.workspace = true
 lazy_static = { workspace = true }
 linkme.workspace = true
 linux-raw-sys = { workspace = true, features = ["ioctl", "loop_device"] }
+lock_api = { version = "0.4.13", features = ["arc_lock"] }
 memory_addr.workspace = true
 num_enum = { version = "0.7", default-features = false }
+ouroboros = { version = "0.18.5", default-features = false }
+percpu = "0.2.0"
 rand = { version = "0.10", default-features = false, features = ["alloc"] }
 ringbuf = { version = "0.4.8", default-features = false, features = ["alloc"] }
 scope-local.workspace = true
@@ -58,13 +64,18 @@ spin.workspace = true
 starry-process.workspace = true
 starry-signal.workspace = true
 starry-vm.workspace = true
+strum = { version = "0.27.2", default-features = false, features = ["derive"] }
 syscalls = { version = "0.8.1", default-features = false }
+uluru = "3.1.0"
+weak-map = "0.1.1"
+xmas-elf = "0.9"
 zerocopy = { version = "0.8.26", features = ["derive"] }
 
-starry-core.workspace = true
-
 [target.'cfg(target_arch = "x86_64")'.dependencies]
 x86 = "0.52"
 
 [target.'cfg(any(target_arch = "riscv32", target_arch = "riscv64"))'.dependencies]
 riscv = "0.16"
+
+[target.'cfg(not(any(target_arch = "aarch64", target_arch = "loongarch64")))'.dependencies]
+axmm = { workspace = true, features = ["copy"] }
diff --git a/core/src/config/aarch64.rs b/kernel/src/config/aarch64.rs
similarity index 100%
rename from core/src/config/aarch64.rs
rename to kernel/src/config/aarch64.rs
diff --git a/core/src/config/loongarch64.rs b/kernel/src/config/loongarch64.rs
similarity index 100%
rename from core/src/config/loongarch64.rs
rename to kernel/src/config/loongarch64.rs
diff --git a/core/src/config/mod.rs b/kernel/src/config/mod.rs
similarity index 100%
rename from core/src/config/mod.rs
rename to kernel/src/config/mod.rs
diff --git a/core/src/config/riscv64.rs b/kernel/src/config/riscv64.rs
similarity index 100%
rename from core/src/config/riscv64.rs
rename to kernel/src/config/riscv64.rs
diff --git a/core/src/config/x86_64.rs b/kernel/src/config/x86_64.rs
similarity index 100%
rename from core/src/config/x86_64.rs
rename to kernel/src/config/x86_64.rs
diff --git a/api/src/file/epoll.rs b/kernel/src/file/epoll.rs
similarity index 100%
rename from api/src/file/epoll.rs
rename to kernel/src/file/epoll.rs
diff --git a/api/src/file/event.rs b/kernel/src/file/event.rs
similarity index 100%
rename from api/src/file/event.rs
rename to kernel/src/file/event.rs
diff --git a/api/src/file/fs.rs b/kernel/src/file/fs.rs
similarity index 100%
rename from api/src/file/fs.rs
rename to kernel/src/file/fs.rs
diff --git a/api/src/file/mod.rs b/kernel/src/file/mod.rs
similarity index 99%
rename from api/src/file/mod.rs
rename to kernel/src/file/mod.rs
index 54def198..33d0c4df 100644
--- a/api/src/file/mod.rs
+++ b/kernel/src/file/mod.rs
@@ -19,7 +19,6 @@ use downcast_rs::{DowncastSync, impl_downcast};
 use flatten_objects::FlattenObjects;
 use linux_raw_sys::general::{RLIMIT_NOFILE, stat, statx, statx_timestamp};
 use spin::RwLock;
-use starry_core::{resources::AX_FILE_LIMIT, task::AsThread};
 
 pub use self::{
     fs::{Directory, File, ResolveAtResult, metadata_to_kstat, resolve_at, with_fs},
@@ -27,6 +26,7 @@ pub use self::{
     pidfd::PidFd,
     pipe::Pipe,
 };
+use crate::task::{AX_FILE_LIMIT, AsThread};
 
 #[derive(Debug, Clone, Copy)]
 pub struct Kstat {
diff --git a/api/src/file/net.rs b/kernel/src/file/net.rs
similarity index 100%
rename from api/src/file/net.rs
rename to kernel/src/file/net.rs
diff --git a/api/src/file/pidfd.rs b/kernel/src/file/pidfd.rs
similarity index 94%
rename from api/src/file/pidfd.rs
rename to kernel/src/file/pidfd.rs
index 3b72ffc2..1debab76 100644
--- a/api/src/file/pidfd.rs
+++ b/kernel/src/file/pidfd.rs
@@ -6,9 +6,8 @@ use core::task::Context;
 
 use axerrno::{AxError, AxResult};
 use axpoll::{IoEvents, PollSet, Pollable};
-use starry_core::task::ProcessData;
 
-use crate::file::FileLike;
+use crate::{file::FileLike, task::ProcessData};
 
 pub struct PidFd {
     proc_data: Weak<ProcessData>,
diff --git a/api/src/file/pipe.rs b/kernel/src/file/pipe.rs
similarity index 98%
rename from api/src/file/pipe.rs
rename to kernel/src/file/pipe.rs
index 8edcde71..e8517073 100644
--- a/api/src/file/pipe.rs
+++ b/kernel/src/file/pipe.rs
@@ -18,12 +18,14 @@ use ringbuf::{
     HeapRb,
     traits::{Consumer, Observer, Producer},
 };
-use starry_core::task::{AsThread, send_signal_to_process};
 use starry_signal::{SignalInfo, Signo};
 use starry_vm::VmMutPtr;
 
 use super::{FileLike, Kstat};
-use crate::file::{IoDst, IoSrc};
+use crate::{
+    file::{IoDst, IoSrc},
+    task::{AsThread, send_signal_to_process},
+};
 
 const RING_BUFFER_INIT_SIZE: usize = 65536; // 64 KiB
 
diff --git a/api/src/file/signalfd.rs b/kernel/src/file/signalfd.rs
similarity index 98%
rename from api/src/file/signalfd.rs
rename to kernel/src/file/signalfd.rs
index c6308c82..08c36807 100644
--- a/api/src/file/signalfd.rs
+++ b/kernel/src/file/signalfd.rs
@@ -12,11 +12,13 @@ use axtask::{
     future::{block_on, poll_io},
 };
 use spin::RwLock;
-use starry_core::task::AsThread;
 use starry_signal::{SignalInfo, SignalSet};
 use zerocopy::{Immutable, IntoBytes};
 
-use crate::file::{FileLike, IoDst, IoSrc};
+use crate::{
+    file::{FileLike, IoDst, IoSrc},
+    task::AsThread,
+};
 
 /// The size of signalfd_siginfo structure (128 bytes as per Linux
 /// specification)
diff --git a/kernel/src/lib.rs b/kernel/src/lib.rs
new file mode 100644
index 00000000..042fdd97
--- /dev/null
+++ b/kernel/src/lib.rs
@@ -0,0 +1,30 @@
+//! The core functionality of a monolithic kernel, including loading user
+//! programs and managing processes.
+
+#![no_std]
+#![feature(likely_unlikely)]
+#![feature(bstr)]
+#![allow(missing_docs)]
+#![allow(clippy::not_unsafe_ptr_arg_deref)]
+
+extern crate alloc;
+
+#[macro_use]
+extern crate axlog;
+
+pub mod config;
+pub mod file;
+pub mod mm;
+pub mod pseudofs;
+pub mod syscall;
+pub mod task;
+pub mod time;
+
+/// Initialize.
+pub fn init() {
+    info!("Initialize pseudofs...");
+    pseudofs::mount_all().expect("Failed to mount pseudofs");
+
+    info!("Initialize alarm...");
+    task::spawn_alarm_task();
+}
diff --git a/api/src/mm.rs b/kernel/src/mm/aspace.rs
similarity index 82%
rename from api/src/mm.rs
rename to kernel/src/mm/aspace.rs
index a6c8c695..313e04ce 100644
--- a/api/src/mm.rs
+++ b/kernel/src/mm/aspace.rs
@@ -9,14 +9,35 @@ use core::{
 
 use axerrno::{AxError, AxResult};
 use axhal::{
+    asm::user_copy,
     paging::MappingFlags,
     trap::{PAGE_FAULT, register_trap_handler},
 };
 use axio::prelude::*;
 use axtask::current;
+use extern_trait::extern_trait;
+use kernel_guard::IrqSave;
 use memory_addr::{MemoryAddr, PAGE_SIZE_4K, VirtAddr};
-use starry_core::{mm::access_user_memory, task::AsThread};
-use starry_vm::{vm_load_until_nul, vm_read_slice, vm_write_slice};
+use starry_vm::{VmError, VmIo, VmResult, vm_load_until_nul, vm_read_slice, vm_write_slice};
+
+use crate::{
+    config::{USER_SPACE_BASE, USER_SPACE_SIZE},
+    task::AsThread,
+};
+
+/// Enables scoped access into user memory, allowing page faults to occur inside
+/// kernel.
+pub fn access_user_memory<R>(f: impl FnOnce() -> R) -> R {
+    let curr = current();
+    let Some(thr) = curr.try_as_thread() else {
+        panic!("access_user_memory called outside of thread context");
+    };
+
+    thr.set_accessing_user_memory(true);
+    let result = f();
+    thr.set_accessing_user_memory(false);
+    result
+}
 
 fn check_region(start: VirtAddr, layout: Layout, access_flags: MappingFlags) -> AxResult<()> {
     let align = layout.align();
@@ -259,6 +280,51 @@ pub fn vm_load_string(ptr: *const c_char) -> AxResult<String> {
     String::from_utf8(bytes).map_err(|_| AxError::IllegalBytes)
 }
 
+#[allow(dead_code)]
+struct Vm(IrqSave);
+
+/// Briefly checks if the given memory region is valid user memory.
+pub fn check_access(start: usize, len: usize) -> VmResult {
+    const USER_SPACE_END: usize = USER_SPACE_BASE + USER_SPACE_SIZE;
+    let ok = (USER_SPACE_BASE..USER_SPACE_END).contains(&start) && (USER_SPACE_END - start) >= len;
+    if unlikely(!ok) {
+        Err(VmError::AccessDenied)
+    } else {
+        Ok(())
+    }
+}
+
+#[extern_trait]
+unsafe impl VmIo for Vm {
+    fn new() -> Self {
+        Self(IrqSave::new())
+    }
+
+    fn read(&mut self, start: usize, buf: &mut [MaybeUninit<u8>]) -> VmResult {
+        check_access(start, buf.len())?;
+        let failed_at = access_user_memory(|| unsafe {
+            user_copy(buf.as_mut_ptr() as *mut _, start as _, buf.len())
+        });
+        if unlikely(failed_at != 0) {
+            Err(VmError::AccessDenied)
+        } else {
+            Ok(())
+        }
+    }
+
+    fn write(&mut self, start: usize, buf: &[u8]) -> VmResult {
+        check_access(start, buf.len())?;
+        let failed_at = access_user_memory(|| unsafe {
+            user_copy(start as _, buf.as_ptr() as *const _, buf.len())
+        });
+        if unlikely(failed_at != 0) {
+            Err(VmError::AccessDenied)
+        } else {
+            Ok(())
+        }
+    }
+}
+
 /// A read-only buffer in the VM's memory.
 ///
 /// It implements the `axio::Read` trait, allowing it to be used with other I/O
diff --git a/api/src/io.rs b/kernel/src/mm/io.rs
similarity index 100%
rename from api/src/io.rs
rename to kernel/src/mm/io.rs
diff --git a/core/src/mm.rs b/kernel/src/mm/loader.rs
similarity index 83%
rename from core/src/mm.rs
rename to kernel/src/mm/loader.rs
index 6672a81a..77d87907 100644
--- a/core/src/mm.rs
+++ b/kernel/src/mm/loader.rs
@@ -1,38 +1,27 @@
 //! User address space management.
 
 use alloc::{borrow::ToOwned, string::String, vec, vec::Vec};
-use core::{ffi::CStr, hint::unlikely, iter, mem::MaybeUninit};
+use core::{ffi::CStr, iter};
 
 use axerrno::{AxError, AxResult};
 use axfs::{CachedFile, FS_CONTEXT, FileBackend};
 use axfs_ng_vfs::Location;
 use axhal::{
-    asm::user_copy,
     mem::virt_to_phys,
     paging::{MappingFlags, PageSize},
 };
 use axmm::{AddrSpace, backend::Backend};
 use axsync::Mutex;
-use axtask::current;
-use extern_trait::extern_trait;
 use kernel_elf_parser::{AuxEntry, ELFHeaders, ELFHeadersBuilder, ELFParser, app_stack_region};
-use kernel_guard::IrqSave;
 use memory_addr::{MemoryAddr, PAGE_SIZE_4K, VirtAddr};
 use ouroboros::self_referencing;
-use starry_vm::{VmError, VmIo, VmResult};
 use uluru::LRUCache;
 
-use crate::{
-    config::{USER_SPACE_BASE, USER_SPACE_SIZE},
-    task::AsThread,
-};
+use crate::config::{USER_SPACE_BASE, USER_SPACE_SIZE};
 
 /// Creates a new empty user address space.
 pub fn new_user_aspace_empty() -> AxResult<AddrSpace> {
-    AddrSpace::new_empty(
-        VirtAddr::from_usize(crate::config::USER_SPACE_BASE),
-        crate::config::USER_SPACE_SIZE,
-    )
+    AddrSpace::new_empty(VirtAddr::from_usize(USER_SPACE_BASE), USER_SPACE_SIZE)
 }
 
 /// If the target architecture requires it, the kernel portion of the address
@@ -347,62 +336,3 @@ pub fn load_user_app(
 
     Ok((entry, user_sp))
 }
-
-/// Enables scoped access into user memory, allowing page faults to occur inside
-/// kernel.
-pub fn access_user_memory<R>(f: impl FnOnce() -> R) -> R {
-    let curr = current();
-    let Some(thr) = curr.try_as_thread() else {
-        panic!("access_user_memory called outside of thread context");
-    };
-
-    thr.set_accessing_user_memory(true);
-    let result = f();
-    thr.set_accessing_user_memory(false);
-    result
-}
-
-#[allow(dead_code)]
-struct Vm(IrqSave);
-
-/// Briefly checks if the given memory region is valid user memory.
-pub fn check_access(start: usize, len: usize) -> VmResult {
-    const USER_SPACE_END: usize = USER_SPACE_BASE + USER_SPACE_SIZE;
-    let ok = (USER_SPACE_BASE..USER_SPACE_END).contains(&start) && (USER_SPACE_END - start) >= len;
-    if unlikely(!ok) {
-        Err(VmError::AccessDenied)
-    } else {
-        Ok(())
-    }
-}
-
-#[extern_trait]
-unsafe impl VmIo for Vm {
-    fn new() -> Self {
-        Self(IrqSave::new())
-    }
-
-    fn read(&mut self, start: usize, buf: &mut [MaybeUninit<u8>]) -> VmResult {
-        check_access(start, buf.len())?;
-        let failed_at = access_user_memory(|| unsafe {
-            user_copy(buf.as_mut_ptr() as *mut _, start as _, buf.len())
-        });
-        if unlikely(failed_at != 0) {
-            Err(VmError::AccessDenied)
-        } else {
-            Ok(())
-        }
-    }
-
-    fn write(&mut self, start: usize, buf: &[u8]) -> VmResult {
-        check_access(start, buf.len())?;
-        let failed_at = access_user_memory(|| unsafe {
-            user_copy(start as _, buf.as_ptr() as *const _, buf.len())
-        });
-        if unlikely(failed_at != 0) {
-            Err(VmError::AccessDenied)
-        } else {
-            Ok(())
-        }
-    }
-}
diff --git a/kernel/src/mm/mod.rs b/kernel/src/mm/mod.rs
new file mode 100644
index 00000000..97e957ea
--- /dev/null
+++ b/kernel/src/mm/mod.rs
@@ -0,0 +1,7 @@
+//! User address space management and user-space memory access.
+
+mod aspace;
+mod io;
+mod loader;
+
+pub use self::{aspace::*, io::*, loader::*};
diff --git a/api/src/vfs/dev/event.rs b/kernel/src/pseudofs/dev/event.rs
similarity index 99%
rename from api/src/vfs/dev/event.rs
rename to kernel/src/pseudofs/dev/event.rs
index 389ede1e..683874a7 100644
--- a/api/src/vfs/dev/event.rs
+++ b/kernel/src/pseudofs/dev/event.rs
@@ -15,10 +15,12 @@ use linux_raw_sys::{
     general::{__kernel_old_time_t, __kernel_suseconds_t},
     ioctl::{EVIOCGID, EVIOCGRAB, EVIOCGVERSION},
 };
-use starry_core::vfs::{Device, DeviceOps, DirMapping, SimpleFs};
 use zerocopy::{FromBytes, Immutable, IntoBytes};
 
-use crate::mm::UserPtr;
+use crate::{
+    mm::UserPtr,
+    pseudofs::{Device, DeviceOps, DirMapping, SimpleFs},
+};
 const KEY_CNT: usize = EventType::Key.bits_count();
 
 struct Inner {
diff --git a/api/src/vfs/dev/fb.rs b/kernel/src/pseudofs/dev/fb.rs
similarity index 99%
rename from api/src/vfs/dev/fb.rs
rename to kernel/src/pseudofs/dev/fb.rs
index 27069dea..2ca919d0 100644
--- a/api/src/vfs/dev/fb.rs
+++ b/kernel/src/pseudofs/dev/fb.rs
@@ -6,9 +6,10 @@ use axerrno::AxError;
 use axfs_ng_vfs::{NodeFlags, VfsError, VfsResult};
 use axhal::mem::virt_to_phys;
 use memory_addr::{PhysAddrRange, VirtAddr};
-use starry_core::vfs::{DeviceMmap, DeviceOps};
 use starry_vm::VmMutPtr;
 
+use crate::pseudofs::{DeviceMmap, DeviceOps};
+
 // Types from https://github.com/Tangzh33/asterinas
 
 #[repr(C)]
diff --git a/api/src/vfs/dev/log.rs b/kernel/src/pseudofs/dev/log.rs
similarity index 100%
rename from api/src/vfs/dev/log.rs
rename to kernel/src/pseudofs/dev/log.rs
diff --git a/api/src/vfs/dev/loop.rs b/kernel/src/pseudofs/dev/loop.rs
similarity index 98%
rename from api/src/vfs/dev/loop.rs
rename to kernel/src/pseudofs/dev/loop.rs
index fc4d5d74..679387c7 100644
--- a/api/src/vfs/dev/loop.rs
+++ b/kernel/src/pseudofs/dev/loop.rs
@@ -11,10 +11,12 @@ use linux_raw_sys::{
     ioctl::{BLKGETSIZE, BLKGETSIZE64, BLKRAGET, BLKRASET, BLKROGET, BLKROSET},
     loop_device::{LOOP_CLR_FD, LOOP_GET_STATUS, LOOP_SET_FD, LOOP_SET_STATUS, loop_info},
 };
-use starry_core::vfs::{DeviceMmap, DeviceOps};
 use starry_vm::{VmMutPtr, VmPtr};
 
-use crate::file::get_file_like;
+use crate::{
+    file::get_file_like,
+    pseudofs::{DeviceMmap, DeviceOps},
+};
 
 /// /dev/loopX devices
 pub struct LoopDevice {
diff --git a/api/src/vfs/dev/memtrack.rs b/kernel/src/pseudofs/dev/memtrack.rs
similarity index 99%
rename from api/src/vfs/dev/memtrack.rs
rename to kernel/src/pseudofs/dev/memtrack.rs
index c1b99a2d..9eb7c477 100644
--- a/api/src/vfs/dev/memtrack.rs
+++ b/kernel/src/pseudofs/dev/memtrack.rs
@@ -8,13 +8,13 @@ use core::{
 
 use axbacktrace::Backtrace;
 use axfs_ng_vfs::{NodeFlags, VfsResult};
-use starry_core::{
+
+use crate::{
     mm::clear_elf_cache,
     task::{cleanup_task_tables, tasks},
+    vfs::DeviceOps,
 };
 
-use crate::vfs::DeviceOps;
-
 static STAMPED_GENERATION: AtomicU64 = AtomicU64::new(0);
 
 #[derive(PartialEq, Eq, PartialOrd, Ord)]
diff --git a/api/src/vfs/dev/mod.rs b/kernel/src/pseudofs/dev/mod.rs
similarity index 97%
rename from api/src/vfs/dev/mod.rs
rename to kernel/src/pseudofs/dev/mod.rs
index dbd0c8d4..68410e1a 100644
--- a/api/src/vfs/dev/mod.rs
+++ b/kernel/src/pseudofs/dev/mod.rs
@@ -20,7 +20,8 @@ use axsync::Mutex;
 #[cfg(feature = "dev-log")]
 pub use log::bind_dev_log;
 use rand::{Rng, SeedableRng, rngs::SmallRng};
-use starry_core::vfs::{Device, DeviceOps, DirMaker, DirMapping, SimpleDir, SimpleFs};
+
+use crate::pseudofs::{Device, DeviceOps, DirMaker, DirMapping, SimpleDir, SimpleFs};
 
 const RANDOM_SEED: &[u8; 32] = b"0123456789abcdef0123456789abcdef";
 
@@ -244,7 +245,7 @@ fn builder(fs: Arc<SimpleFs>) -> DirMaker {
     #[cfg(feature = "dev-log")]
     root.add(
         "log",
-        starry_core::vfs::SimpleFile::new(fs.clone(), NodeType::Socket, || Ok(b"")),
+        crate::pseudofs::SimpleFile::new(fs.clone(), NodeType::Socket, || Ok(b"")),
     );
 
     #[cfg(feature = "memtrack")]
diff --git a/api/src/vfs/dev/rtc.rs b/kernel/src/pseudofs/dev/rtc.rs
similarity index 98%
rename from api/src/vfs/dev/rtc.rs
rename to kernel/src/pseudofs/dev/rtc.rs
index 6eefe2bd..1131dbb3 100644
--- a/api/src/vfs/dev/rtc.rs
+++ b/kernel/src/pseudofs/dev/rtc.rs
@@ -5,7 +5,7 @@ use chrono::{Datelike, Timelike};
 use linux_raw_sys::ioctl::RTC_RD_TIME;
 use starry_vm::VmMutPtr;
 
-use crate::vfs::DeviceOps;
+use crate::pseudofs::DeviceOps;
 
 /// The device ID for /dev/rtc0
 pub const RTC0_DEVICE_ID: DeviceId = DeviceId::new(250, 0);
diff --git a/api/src/vfs/dev/tty.rs b/kernel/src/pseudofs/dev/tty/mod.rs
similarity index 95%
rename from api/src/vfs/dev/tty.rs
rename to kernel/src/pseudofs/dev/tty/mod.rs
index a26dfc32..fa8c1971 100644
--- a/api/src/vfs/dev/tty.rs
+++ b/kernel/src/pseudofs/dev/tty/mod.rs
@@ -1,3 +1,9 @@
+mod ntty;
+mod ptm;
+mod pts;
+mod pty;
+mod terminal;
+
 use alloc::sync::{Arc, Weak};
 use core::{any::Any, ops::Deref, sync::atomic::Ordering, task::Context};
 
@@ -9,29 +15,25 @@ use axtask::{
     current,
     future::{block_on, poll_io},
 };
-use starry_core::{task::AsThread, vfs::SimpleFs};
 use starry_process::Process;
 use starry_vm::{VmMutPtr, VmPtr};
 
+use self::terminal::{
+    Terminal, WindowSize,
+    ldisc::{LineDiscipline, ProcessMode, TtyConfig, TtyRead, TtyWrite},
+    termios::{Termios, Termios2},
+};
+pub use self::{
+    ntty::{N_TTY, NTtyDriver},
+    ptm::Ptmx,
+    pts::PtsDir,
+    pty::PtyDriver,
+};
 use crate::{
-    terminal::{
-        Terminal, WindowSize,
-        ldisc::{LineDiscipline, ProcessMode, TtyConfig, TtyRead, TtyWrite},
-        termios::{Termios, Termios2},
-    },
-    vfs::DeviceOps,
+    pseudofs::{DeviceOps, SimpleFs},
+    task::AsThread,
 };
 
-mod ntty;
-mod ptm;
-mod pts;
-mod pty;
-
-pub use ntty::{N_TTY, NTtyDriver};
-pub use ptm::Ptmx;
-pub use pts::PtsDir;
-pub use pty::PtyDriver;
-
 pub fn create_pty_master(fs: Arc<SimpleFs>) -> AxResult<Arc<PtyDriver>> {
     let (master, slave) = pty::create_pty_pair();
     pts::add_slave(fs, slave)?;
diff --git a/api/src/vfs/dev/tty/ntty.rs b/kernel/src/pseudofs/dev/tty/ntty.rs
similarity index 91%
rename from api/src/vfs/dev/tty/ntty.rs
rename to kernel/src/pseudofs/dev/tty/ntty.rs
index a4a1d55b..2b3e6eb6 100644
--- a/api/src/vfs/dev/tty/ntty.rs
+++ b/kernel/src/pseudofs/dev/tty/ntty.rs
@@ -3,8 +3,10 @@ use alloc::{boxed::Box, sync::Arc};
 use axtask::future::register_irq_waker;
 use lazy_static::lazy_static;
 
-use super::Tty;
-use crate::terminal::ldisc::{ProcessMode, TtyConfig, TtyRead, TtyWrite};
+use super::{
+    Tty,
+    terminal::ldisc::{ProcessMode, TtyConfig, TtyRead, TtyWrite},
+};
 
 pub type NTtyDriver = Tty<Console, Console>;
 
diff --git a/api/src/vfs/dev/tty/ptm.rs b/kernel/src/pseudofs/dev/tty/ptm.rs
similarity index 95%
rename from api/src/vfs/dev/tty/ptm.rs
rename to kernel/src/pseudofs/dev/tty/ptm.rs
index 37f538cf..1c3f0c0c 100644
--- a/api/src/vfs/dev/tty/ptm.rs
+++ b/kernel/src/pseudofs/dev/tty/ptm.rs
@@ -3,7 +3,8 @@ use core::any::Any;
 
 use axerrno::AxResult;
 use axfs_ng_vfs::{DeviceId, NodeType};
-use starry_core::vfs::{Device, DeviceOps, SimpleFs};
+
+use crate::pseudofs::{Device, DeviceOps, SimpleFs};
 
 pub struct Ptmx(pub Arc<SimpleFs>);
 impl Ptmx {
diff --git a/api/src/vfs/dev/tty/pts.rs b/kernel/src/pseudofs/dev/tty/pts.rs
similarity index 93%
rename from api/src/vfs/dev/tty/pts.rs
rename to kernel/src/pseudofs/dev/tty/pts.rs
index fe927891..f3c4b47b 100644
--- a/api/src/vfs/dev/tty/pts.rs
+++ b/kernel/src/pseudofs/dev/tty/pts.rs
@@ -5,9 +5,8 @@ use axerrno::{AxError, AxResult};
 use axfs_ng_vfs::{DeviceId, NodeType, VfsResult};
 use flatten_objects::FlattenObjects;
 use kspin::SpinNoIrq;
-use starry_core::vfs::{Device, NodeOpsMux, SimpleDirOps, SimpleFs};
 
-use crate::vfs::dev::tty::pty::PtyDriver;
+use crate::pseudofs::{Device, NodeOpsMux, SimpleDirOps, SimpleFs, dev::tty::pty::PtyDriver};
 
 static PTS_TABLE: SpinNoIrq<FlattenObjects<Arc<Device>, 16>> =
     SpinNoIrq::new(FlattenObjects::new());
diff --git a/api/src/vfs/dev/tty/pty.rs b/kernel/src/pseudofs/dev/tty/pty.rs
similarity index 94%
rename from api/src/vfs/dev/tty/pty.rs
rename to kernel/src/pseudofs/dev/tty/pty.rs
index 821f5a9c..7114b933 100644
--- a/api/src/vfs/dev/tty/pty.rs
+++ b/kernel/src/pseudofs/dev/tty/pty.rs
@@ -7,10 +7,12 @@ use ringbuf::{
     traits::{Consumer, Producer},
 };
 
-use super::Tty;
-use crate::terminal::{
-    Terminal,
-    ldisc::{ProcessMode, TtyConfig, TtyRead, TtyWrite},
+use super::{
+    Tty,
+    terminal::{
+        Terminal,
+        ldisc::{ProcessMode, TtyConfig, TtyRead, TtyWrite},
+    },
 };
 
 const PTY_BUF_SIZE: usize = 4096;
diff --git a/api/src/terminal/job.rs b/kernel/src/pseudofs/dev/tty/terminal/job.rs
similarity index 98%
rename from api/src/terminal/job.rs
rename to kernel/src/pseudofs/dev/tty/terminal/job.rs
index b0757c63..0b3d6156 100644
--- a/api/src/terminal/job.rs
+++ b/kernel/src/pseudofs/dev/tty/terminal/job.rs
@@ -5,9 +5,10 @@ use axerrno::{AxResult, ax_bail};
 use axpoll::{IoEvents, PollSet, Pollable};
 use axtask::current;
 use kspin::SpinNoIrq;
-use starry_core::task::AsThread;
 use starry_process::{ProcessGroup, Session};
 
+use crate::task::AsThread;
+
 pub struct JobControl {
     foreground: SpinNoIrq<Weak<ProcessGroup>>,
     session: SpinNoIrq<Weak<Session>>,
diff --git a/api/src/terminal/ldisc.rs b/kernel/src/pseudofs/dev/tty/terminal/ldisc.rs
similarity index 99%
rename from api/src/terminal/ldisc.rs
rename to kernel/src/pseudofs/dev/tty/terminal/ldisc.rs
index 06cf6be5..a6af02f5 100644
--- a/api/src/terminal/ldisc.rs
+++ b/kernel/src/pseudofs/dev/tty/terminal/ldisc.rs
@@ -16,10 +16,10 @@ use ringbuf::{
     CachingCons, CachingProd,
     traits::{Consumer, Observer, Producer, Split},
 };
-use starry_core::task::send_signal_to_process_group;
 use starry_signal::SignalInfo;
 
-use crate::terminal::{Terminal, termios::Termios2};
+use super::{Terminal, termios::Termios2};
+use crate::task::send_signal_to_process_group;
 
 const BUF_SIZE: usize = 80;
 
diff --git a/api/src/terminal/mod.rs b/kernel/src/pseudofs/dev/tty/terminal/mod.rs
similarity index 100%
rename from api/src/terminal/mod.rs
rename to kernel/src/pseudofs/dev/tty/terminal/mod.rs
diff --git a/api/src/terminal/termios.rs b/kernel/src/pseudofs/dev/tty/terminal/termios.rs
similarity index 99%
rename from api/src/terminal/termios.rs
rename to kernel/src/pseudofs/dev/tty/terminal/termios.rs
index 94532eb1..9064fd6c 100644
--- a/api/src/terminal/termios.rs
+++ b/kernel/src/pseudofs/dev/tty/terminal/termios.rs
@@ -1,3 +1,5 @@
+#![allow(dead_code)]
+
 use core::ops::{Deref, DerefMut};
 
 use bytemuck::AnyBitPattern;
diff --git a/core/src/vfs/dev.rs b/kernel/src/pseudofs/device.rs
similarity index 100%
rename from core/src/vfs/dev.rs
rename to kernel/src/pseudofs/device.rs
diff --git a/core/src/vfs/dir.rs b/kernel/src/pseudofs/dir.rs
similarity index 100%
rename from core/src/vfs/dir.rs
rename to kernel/src/pseudofs/dir.rs
diff --git a/core/src/vfs/file.rs b/kernel/src/pseudofs/file.rs
similarity index 100%
rename from core/src/vfs/file.rs
rename to kernel/src/pseudofs/file.rs
diff --git a/core/src/vfs/fs.rs b/kernel/src/pseudofs/fs.rs
similarity index 100%
rename from core/src/vfs/fs.rs
rename to kernel/src/pseudofs/fs.rs
diff --git a/api/src/vfs/mod.rs b/kernel/src/pseudofs/mod.rs
similarity index 60%
rename from api/src/vfs/mod.rs
rename to kernel/src/pseudofs/mod.rs
index 60ffd35a..40fcec4e 100644
--- a/api/src/vfs/mod.rs
+++ b/kernel/src/pseudofs/mod.rs
@@ -1,18 +1,51 @@
-//! Virtual filesystems
+//! Basic virtual filesystem support
 
 pub mod dev;
+mod device;
+mod dir;
+mod file;
+mod fs;
 mod proc;
 mod tmp;
 
+use alloc::sync::Arc;
+
 use axerrno::LinuxResult;
 use axfs::{FS_CONTEXT, FsContext};
 use axfs_ng_vfs::{
-    Filesystem, NodePermission,
+    DirNodeOps, FileNodeOps, Filesystem, NodePermission, WeakDirEntry,
     path::{Path, PathBuf},
 };
-pub use starry_core::vfs::{Device, DeviceOps, DirMapping, SimpleFs};
 pub use tmp::MemoryFs;
 
+pub use self::{device::*, dir::*, file::*, fs::*};
+
+/// A callback that builds a `Arc<dyn DirNodeOps>` for a given
+/// `WeakDirEntry`.
+pub type DirMaker = Arc<dyn Fn(WeakDirEntry) -> Arc<dyn DirNodeOps> + Send + Sync>;
+
+/// An enum containing either a directory ([`DirMaker`]) or a file (`Arc<dyn
+/// FileNodeOps>`).
+#[derive(Clone)]
+pub enum NodeOpsMux {
+    /// A directory node.
+    Dir(DirMaker),
+    /// A file node.
+    File(Arc<dyn FileNodeOps>),
+}
+
+impl From<DirMaker> for NodeOpsMux {
+    fn from(maker: DirMaker) -> Self {
+        Self::Dir(maker)
+    }
+}
+
+impl<T: FileNodeOps> From<Arc<T>> for NodeOpsMux {
+    fn from(ops: Arc<T>) -> Self {
+        Self::File(ops)
+    }
+}
+
 const DIR_PERMISSION: NodePermission = NodePermission::from_bits_truncate(0o755);
 
 fn mount_at(fs: &FsContext, path: &str, mount_fs: Filesystem) -> LinuxResult<()> {
diff --git a/api/src/vfs/proc.rs b/kernel/src/pseudofs/proc.rs
similarity index 96%
rename from api/src/vfs/proc.rs
rename to kernel/src/pseudofs/proc.rs
index 8635d89e..0f988464 100644
--- a/api/src/vfs/proc.rs
+++ b/kernel/src/pseudofs/proc.rs
@@ -7,21 +7,25 @@ use alloc::{
     vec,
     vec::Vec,
 };
-use core::{ffi::CStr, iter};
+use core::{
+    ffi::CStr,
+    iter,
+    sync::atomic::{AtomicUsize, Ordering},
+};
 
 use axfs_ng_vfs::{Filesystem, NodeType, VfsError, VfsResult};
 use axtask::{AxTaskRef, WeakAxTaskRef, current};
 use indoc::indoc;
-use starry_core::{
-    task::{AsThread, TaskStat, get_task, tasks},
-    vfs::{
+use starry_process::Process;
+
+use crate::{
+    file::FD_TABLE,
+    pseudofs::{
         DirMaker, DirMapping, NodeOpsMux, RwFile, SimpleDir, SimpleDirOps, SimpleFile,
         SimpleFileOperation, SimpleFs,
     },
+    task::{AsThread, TaskStat, get_task, tasks},
 };
-use starry_process::Process;
-
-use crate::file::FD_TABLE;
 
 const DUMMY_MEMINFO: &str = indoc! {"
     MemTotal:       32536204 kB
@@ -384,10 +388,20 @@ fn builder(fs: Arc<SimpleFs>) -> DirMaker {
             }
         }),
     );
-    root.add(
-        "interrupts",
-        SimpleFile::new_regular(fs.clone(), || Ok(format!("0: {}", crate::time::irq_cnt()))),
-    );
+    {
+        static IRQ_CNT: AtomicUsize = AtomicUsize::new(0);
+
+        axtask::register_timer_callback(|_| {
+            IRQ_CNT.fetch_add(1, Ordering::Relaxed);
+        });
+
+        root.add(
+            "interrupts",
+            SimpleFile::new_regular(fs.clone(), || {
+                Ok(format!("0: {}", IRQ_CNT.load(Ordering::Relaxed)))
+            }),
+        );
+    }
 
     root.add("sys", {
         let mut sys = DirMapping::new();
diff --git a/api/src/vfs/tmp.rs b/kernel/src/pseudofs/tmp.rs
similarity index 99%
rename from api/src/vfs/tmp.rs
rename to kernel/src/pseudofs/tmp.rs
index 09c454db..2a2798a3 100644
--- a/api/src/vfs/tmp.rs
+++ b/kernel/src/pseudofs/tmp.rs
@@ -10,7 +10,8 @@ use axpoll::{IoEvents, Pollable};
 use axsync::Mutex;
 use hashbrown::HashMap;
 use slab::Slab;
-use starry_core::vfs::dummy_stat_fs;
+
+use crate::pseudofs::dummy_stat_fs;
 
 #[derive(PartialEq, Eq, Hash, Clone)]
 struct FileName(String);
diff --git a/api/src/syscall/fs/ctl.rs b/kernel/src/syscall/fs/ctl.rs
similarity index 99%
rename from api/src/syscall/fs/ctl.rs
rename to kernel/src/syscall/fs/ctl.rs
index ef8cd9cb..32179b92 100644
--- a/api/src/syscall/fs/ctl.rs
+++ b/kernel/src/syscall/fs/ctl.rs
@@ -14,12 +14,12 @@ use linux_raw_sys::{
     general::*,
     ioctl::{FIONBIO, TIOCGWINSZ},
 };
-use starry_core::task::AsThread;
 use starry_vm::{VmPtr, vm_write_slice};
 
 use crate::{
     file::{Directory, FileLike, get_file_like, resolve_at, with_fs},
     mm::vm_load_string,
+    task::AsThread,
     time::TimeValueLike,
 };
 
diff --git a/api/src/syscall/fs/event.rs b/kernel/src/syscall/fs/event.rs
similarity index 100%
rename from api/src/syscall/fs/event.rs
rename to kernel/src/syscall/fs/event.rs
diff --git a/api/src/syscall/fs/fd_ops.rs b/kernel/src/syscall/fs/fd_ops.rs
similarity index 99%
rename from api/src/syscall/fs/fd_ops.rs
rename to kernel/src/syscall/fs/fd_ops.rs
index 825ee48b..44f0090d 100644
--- a/api/src/syscall/fs/fd_ops.rs
+++ b/kernel/src/syscall/fs/fd_ops.rs
@@ -11,7 +11,6 @@ use axfs_ng_vfs::{DirEntry, FileNode, Location, NodePermission, NodeType, Refere
 use axtask::current;
 use bitflags::bitflags;
 use linux_raw_sys::general::*;
-use starry_core::{task::AsThread, vfs::Device};
 
 use crate::{
     file::{
@@ -20,7 +19,8 @@ use crate::{
     },
     mm::{UserPtr, vm_load_string},
     syscall::sys::{sys_getegid, sys_geteuid},
-    vfs::dev::tty,
+    task::AsThread,
+    pseudofs::{Device, dev::tty},
 };
 
 /// Convert open flags to [`OpenOptions`].
diff --git a/api/src/syscall/fs/io.rs b/kernel/src/syscall/fs/io.rs
similarity index 99%
rename from api/src/syscall/fs/io.rs
rename to kernel/src/syscall/fs/io.rs
index a3be9d4a..30b0ed14 100644
--- a/api/src/syscall/fs/io.rs
+++ b/kernel/src/syscall/fs/io.rs
@@ -15,8 +15,7 @@ use syscalls::Sysno;
 
 use crate::{
     file::{File, FileLike, Pipe, get_file_like},
-    io::{IoVec, IoVectorBuf},
-    mm::{UserConstPtr, VmBytes, VmBytesMut},
+    mm::{IoVec, IoVectorBuf, UserConstPtr, VmBytes, VmBytesMut},
 };
 
 struct DummyFd;
diff --git a/api/src/syscall/fs/memfd.rs b/kernel/src/syscall/fs/memfd.rs
similarity index 100%
rename from api/src/syscall/fs/memfd.rs
rename to kernel/src/syscall/fs/memfd.rs
diff --git a/api/src/syscall/fs/mod.rs b/kernel/src/syscall/fs/mod.rs
similarity index 100%
rename from api/src/syscall/fs/mod.rs
rename to kernel/src/syscall/fs/mod.rs
diff --git a/api/src/syscall/fs/mount.rs b/kernel/src/syscall/fs/mount.rs
similarity index 94%
rename from api/src/syscall/fs/mount.rs
rename to kernel/src/syscall/fs/mount.rs
index 9efb5c31..057662b2 100644
--- a/api/src/syscall/fs/mount.rs
+++ b/kernel/src/syscall/fs/mount.rs
@@ -3,7 +3,7 @@ use core::ffi::{c_char, c_void};
 use axerrno::{AxError, AxResult};
 use axfs::FS_CONTEXT;
 
-use crate::{mm::vm_load_string, vfs::MemoryFs};
+use crate::{mm::vm_load_string, pseudofs::MemoryFs};
 
 pub fn sys_mount(
     source: *const c_char,
diff --git a/api/src/syscall/fs/pidfd.rs b/kernel/src/syscall/fs/pidfd.rs
similarity index 95%
rename from api/src/syscall/fs/pidfd.rs
rename to kernel/src/syscall/fs/pidfd.rs
index 05804aa5..2d3d924f 100644
--- a/api/src/syscall/fs/pidfd.rs
+++ b/kernel/src/syscall/fs/pidfd.rs
@@ -1,10 +1,10 @@
 use axerrno::{AxError, AxResult};
-use starry_core::task::{get_process_data, send_signal_to_process};
 use starry_signal::SignalInfo;
 
 use crate::{
     file::{FD_TABLE, FileLike, PidFd, add_file_like},
     syscall::signal::make_queue_signal_info,
+    task::{get_process_data, send_signal_to_process},
 };
 
 pub fn sys_pidfd_open(pid: u32, flags: u32) -> AxResult<isize> {
diff --git a/api/src/syscall/fs/pipe.rs b/kernel/src/syscall/fs/pipe.rs
similarity index 100%
rename from api/src/syscall/fs/pipe.rs
rename to kernel/src/syscall/fs/pipe.rs
diff --git a/api/src/syscall/fs/signalfd.rs b/kernel/src/syscall/fs/signalfd.rs
similarity index 100%
rename from api/src/syscall/fs/signalfd.rs
rename to kernel/src/syscall/fs/signalfd.rs
diff --git a/api/src/syscall/fs/stat.rs b/kernel/src/syscall/fs/stat.rs
similarity index 100%
rename from api/src/syscall/fs/stat.rs
rename to kernel/src/syscall/fs/stat.rs
diff --git a/api/src/syscall/io_mpx/epoll.rs b/kernel/src/syscall/io_mpx/epoll.rs
similarity index 98%
rename from api/src/syscall/io_mpx/epoll.rs
rename to kernel/src/syscall/io_mpx/epoll.rs
index 05b76286..5243f0ee 100644
--- a/api/src/syscall/io_mpx/epoll.rs
+++ b/kernel/src/syscall/io_mpx/epoll.rs
@@ -15,8 +15,8 @@ use crate::{
         epoll::{Epoll, EpollEvent, EpollFlags},
     },
     mm::{UserConstPtr, UserPtr, nullable},
-    signal::with_replacen_blocked,
     syscall::signal::check_sigset_size,
+    task::with_blocked_signals,
     time::TimeValueLike,
 };
 
@@ -93,7 +93,7 @@ fn do_epoll_wait(
     }
     let events = events.get_as_mut_slice(maxevents as usize)?;
 
-    with_replacen_blocked(
+    with_blocked_signals(
         nullable!(sigmask.get_as_ref())?.copied(),
         || match block_on(future::timeout(
             timeout,
diff --git a/api/src/syscall/io_mpx/mod.rs b/kernel/src/syscall/io_mpx/mod.rs
similarity index 100%
rename from api/src/syscall/io_mpx/mod.rs
rename to kernel/src/syscall/io_mpx/mod.rs
diff --git a/api/src/syscall/io_mpx/poll.rs b/kernel/src/syscall/io_mpx/poll.rs
similarity index 97%
rename from api/src/syscall/io_mpx/poll.rs
rename to kernel/src/syscall/io_mpx/poll.rs
index 30fae238..58f0d7f3 100644
--- a/api/src/syscall/io_mpx/poll.rs
+++ b/kernel/src/syscall/io_mpx/poll.rs
@@ -11,8 +11,8 @@ use super::FdPollSet;
 use crate::{
     file::get_file_like,
     mm::{UserConstPtr, UserPtr, nullable},
-    signal::with_replacen_blocked,
     syscall::signal::check_sigset_size,
+    task::with_blocked_signals,
     time::TimeValueLike,
 };
 
@@ -52,7 +52,7 @@ fn do_poll(
     }
     let fds = FdPollSet(fds);
 
-    with_replacen_blocked(sigmask, || {
+    with_blocked_signals(sigmask, || {
         match block_on(future::timeout(
             timeout,
             poll_io(&fds, IoEvents::empty(), false, || {
diff --git a/api/src/syscall/io_mpx/select.rs b/kernel/src/syscall/io_mpx/select.rs
similarity index 98%
rename from api/src/syscall/io_mpx/select.rs
rename to kernel/src/syscall/io_mpx/select.rs
index 3ff65f99..e05b592b 100644
--- a/api/src/syscall/io_mpx/select.rs
+++ b/kernel/src/syscall/io_mpx/select.rs
@@ -15,8 +15,8 @@ use super::FdPollSet;
 use crate::{
     file::FD_TABLE,
     mm::{UserConstPtr, UserPtr, nullable},
-    signal::with_replacen_blocked,
     syscall::signal::check_sigset_size,
+    task::with_blocked_signals,
     time::TimeValueLike,
 };
 
@@ -107,7 +107,7 @@ fn do_select(
     if let Some(exceptfds) = exceptfds.as_deref_mut() {
         unsafe { FD_ZERO(exceptfds) };
     }
-    with_replacen_blocked(sigmask.copied(), || {
+    with_blocked_signals(sigmask.copied(), || {
         match block_on(future::timeout(
             timeout,
             poll_io(&fds, IoEvents::empty(), false, || {
diff --git a/api/src/syscall/ipc/mod.rs b/kernel/src/syscall/ipc/mod.rs
similarity index 59%
rename from api/src/syscall/ipc/mod.rs
rename to kernel/src/syscall/ipc/mod.rs
index fe56b504..52a41039 100644
--- a/api/src/syscall/ipc/mod.rs
+++ b/kernel/src/syscall/ipc/mod.rs
@@ -1,6 +1,14 @@
 use core::sync::atomic::{AtomicI32, Ordering};
 
-use starry_core::shm::IpcPerm;
+mod msg;
+mod shm;
+use bytemuck::AnyBitPattern;
+use linux_raw_sys::{
+    ctypes::{c_long, c_ushort},
+    general::*,
+};
+
+pub use self::{msg::*, shm::*};
 
 static IPC_ID: AtomicI32 = AtomicI32::new(0);
 
@@ -8,10 +16,6 @@ fn next_ipc_id() -> i32 {
     IPC_ID.fetch_add(1, Ordering::Relaxed)
 }
 
-mod msg;
-mod shm;
-pub use self::{msg::*, shm::*};
-
 // IPC command constants
 const IPC_PRIVATE: i32 = 0;
 const IPC_CREAT: i32 = 0o1000;
@@ -31,6 +35,32 @@ const GROUP_WRITE: u32 = 0o020;
 const OTHER_READ: u32 = 0o004;
 const OTHER_WRITE: u32 = 0o002;
 
+/// Data structure used to pass permission information to IPC operations.
+#[repr(C)]
+#[derive(Clone, Copy, AnyBitPattern)]
+pub struct IpcPerm {
+    /// Key supplied to msgget(2)
+    pub key: __kernel_key_t,
+    /// Effective UID of owner
+    pub uid: __kernel_uid_t,
+    /// Effective GID of owner
+    pub gid: __kernel_gid_t,
+    /// Effective UID of creator
+    pub cuid: __kernel_uid_t,
+    /// Effective GID of creator
+    pub cgid: __kernel_gid_t,
+    /// Permissions (least significant 9 bits define access permissions)
+    pub mode: __kernel_mode_t,
+    /// Sequence number
+    pub seq: c_ushort,
+    /// Padding
+    pub pad: c_ushort,
+    /// Unused field
+    pub unused0: c_long,
+    /// Unused field
+    pub unused1: c_long,
+}
+
 // add a helper function to check IPC permissions
 fn has_ipc_permission(perm: &IpcPerm, current_uid: u32, current_gid: u32, is_write: bool) -> bool {
     // root user has all permissions
diff --git a/api/src/syscall/ipc/msg.rs b/kernel/src/syscall/ipc/msg.rs
similarity index 99%
rename from api/src/syscall/ipc/msg.rs
rename to kernel/src/syscall/ipc/msg.rs
index 367732fc..9aed4b6d 100644
--- a/api/src/syscall/ipc/msg.rs
+++ b/kernel/src/syscall/ipc/msg.rs
@@ -6,19 +6,22 @@ use axsync::Mutex;
 use axtask::current;
 use bytemuck::AnyBitPattern;
 use linux_raw_sys::general::*;
-use starry_core::{shm::IpcPerm, task::AsThread};
 use starry_process::Pid;
 use starry_vm::{VmMutPtr, VmPtr, vm_load, vm_write_slice};
 
 use super::{
-    IPC_CREAT, IPC_EXCL, IPC_INFO, IPC_PRIVATE, IPC_RMID, IPC_SET, IPC_STAT, MSG_INFO, MSG_STAT,
-    has_ipc_permission, next_ipc_id,
+    IPC_CREAT, IPC_EXCL, IPC_INFO, IPC_PRIVATE, IPC_RMID, IPC_SET, IPC_STAT, IpcPerm, MSG_INFO,
+    MSG_STAT, has_ipc_permission, next_ipc_id,
+};
+use crate::{
+    syscall::{sys_getgid, sys_getuid},
+    task::AsThread,
 };
-use crate::syscall::{sys_getgid, sys_getuid};
 
 /// Data structure describing a message queue.
 #[repr(C)]
 #[derive(Clone, Copy, AnyBitPattern)]
+#[allow(non_camel_case_types)]
 pub struct msqid_ds {
     /// operation permission struct
     pub msg_perm: IpcPerm,
@@ -718,7 +721,7 @@ pub fn sys_msgctl(msqid: i32, cmd: i32, buf: usize) -> AxResult<isize> {
     if cmd == MSG_INFO {
         let msg_manager = MSG_MANAGER.lock();
         // Manually create IpcPerm
-        let msg_perm = starry_core::shm::IpcPerm {
+        let msg_perm = IpcPerm {
             key: 0,
             uid: current_uid,
             gid: current_gid,
diff --git a/core/src/shm.rs b/kernel/src/syscall/ipc/shm.rs
similarity index 59%
rename from core/src/shm.rs
rename to kernel/src/syscall/ipc/shm.rs
index caae12ff..aba3f705 100644
--- a/core/src/shm.rs
+++ b/kernel/src/syscall/ipc/shm.rs
@@ -1,42 +1,34 @@
-//! Shared memory management.
-
 use alloc::{collections::btree_map::BTreeMap, sync::Arc, vec::Vec};
 
 use axerrno::{AxError, AxResult};
-use axhal::{paging::MappingFlags, time::monotonic_time_nanos};
-use axmm::backend::SharedPages;
-use axsync::Mutex;
-use bytemuck::AnyBitPattern;
-use linux_raw_sys::{
-    ctypes::{c_long, c_ushort},
-    general::*,
+use axhal::{
+    paging::{MappingFlags, PageSize},
+    time::monotonic_time_nanos,
 };
+use axmm::backend::{Backend, SharedPages};
+use axsync::Mutex;
+use axtask::current;
+use linux_raw_sys::{ctypes::c_ushort, general::*};
 use memory_addr::{PAGE_SIZE_4K, VirtAddr, VirtAddrRange};
 use starry_process::Pid;
-/// Data structure used to pass permission information to IPC operations.
-#[repr(C)]
-#[derive(Clone, Copy, AnyBitPattern)]
-pub struct IpcPerm {
-    /// Key supplied to msgget(2)
-    pub key: __kernel_key_t,
-    /// Effective UID of owner
-    pub uid: __kernel_uid_t,
-    /// Effective GID of owner
-    pub gid: __kernel_gid_t,
-    /// Effective UID of creator
-    pub cuid: __kernel_uid_t,
-    /// Effective GID of creator
-    pub cgid: __kernel_gid_t,
-    /// Permissions (least significant 9 bits define access permissions)
-    pub mode: __kernel_mode_t,
-    /// Sequence number
-    pub seq: c_ushort,
-    /// Padding
-    pub pad: c_ushort,
-    /// Unused field
-    pub unused0: c_long,
-    /// Unused field
-    pub unused1: c_long,
+
+use super::{IPC_PRIVATE, IPC_RMID, IPC_SET, IPC_STAT, IpcPerm, next_ipc_id};
+use crate::{
+    mm::{UserPtr, nullable},
+    task::AsThread,
+};
+
+bitflags::bitflags! {
+    /// flags for sys_shmat
+    #[derive(Debug)]
+    struct ShmAtFlags: u32 {
+        /* attach read-only else read-write */
+        const SHM_RDONLY = 0o10000;
+        /* round attach address to SHMLBA */
+        const SHM_RND = 0o20000;
+        /* take-over region on attach */
+        const SHM_REMAP = 0o40000;
+    }
 }
 
 /// Data structure describing a shared memory segment.
@@ -379,3 +371,199 @@ impl ShmManager {
 
 /// Global shared memory manager.
 pub static SHM_MANAGER: Mutex<ShmManager> = Mutex::new(ShmManager::new());
+
+pub fn sys_shmget(key: i32, size: usize, shmflg: usize) -> AxResult<isize> {
+    let page_num = memory_addr::align_up_4k(size) / PAGE_SIZE_4K;
+    if page_num == 0 {
+        return Err(AxError::InvalidInput);
+    }
+
+    let mut mapping_flags = MappingFlags::from_name("USER").unwrap();
+    if shmflg & 0o400 != 0 {
+        mapping_flags.insert(MappingFlags::READ);
+    }
+    if shmflg & 0o200 != 0 {
+        mapping_flags.insert(MappingFlags::WRITE);
+    }
+    if shmflg & 0o100 != 0 {
+        mapping_flags.insert(MappingFlags::EXECUTE);
+    }
+
+    let cur_pid = current().as_thread().proc_data.proc.pid();
+    let mut shm_manager = SHM_MANAGER.lock();
+
+    if key != IPC_PRIVATE {
+        // This process has already created a shared memory segment with the same key
+        if let Some(shmid) = shm_manager.get_shmid_by_key(key) {
+            let shm_inner = shm_manager
+                .get_inner_by_shmid(shmid)
+                .ok_or(AxError::InvalidInput)?;
+            let mut shm_inner = shm_inner.lock();
+            return shm_inner.try_update(size, mapping_flags, cur_pid);
+        }
+    }
+
+    // Create a new shm_inner
+    let shmid = next_ipc_id();
+    let shm_inner = Arc::new(Mutex::new(ShmInner::new(
+        key,
+        shmid,
+        size,
+        mapping_flags,
+        cur_pid,
+    )));
+    shm_manager.insert_key_shmid(key, shmid);
+    shm_manager.insert_shmid_inner(shmid, shm_inner);
+
+    Ok(shmid as isize)
+}
+
+pub fn sys_shmat(shmid: i32, addr: usize, shmflg: u32) -> AxResult<isize> {
+    let shm_inner = {
+        let shm_manager = SHM_MANAGER.lock();
+        shm_manager.get_inner_by_shmid(shmid).unwrap()
+    };
+    let mut shm_inner = shm_inner.lock();
+    let mut mapping_flags = shm_inner.mapping_flags;
+    let shm_flg = ShmAtFlags::from_bits_truncate(shmflg);
+
+    if shm_flg.contains(ShmAtFlags::SHM_RDONLY) {
+        mapping_flags.remove(MappingFlags::WRITE);
+    }
+
+    // TODO: solve shmflg: SHM_RND and SHM_REMAP
+
+    let curr = current();
+    let proc_data = &curr.as_thread().proc_data;
+    let pid = proc_data.proc.pid();
+    let mut aspace = proc_data.aspace.lock();
+
+    let start_aligned = memory_addr::align_down_4k(addr);
+    let length = shm_inner.page_num * PAGE_SIZE_4K;
+
+    // alloc the virtual address range
+    assert!(shm_inner.get_addr_range(pid).is_none());
+    let start_addr = aspace
+        .find_free_area(
+            VirtAddr::from(start_aligned),
+            length,
+            VirtAddrRange::new(aspace.base(), aspace.end()),
+            PAGE_SIZE_4K,
+        )
+        .or_else(|| {
+            aspace.find_free_area(
+                aspace.base(),
+                length,
+                VirtAddrRange::new(aspace.base(), aspace.end()),
+                PAGE_SIZE_4K,
+            )
+        })
+        .ok_or(AxError::NoMemory)?;
+    let end_addr = VirtAddr::from(start_addr.as_usize() + length);
+    let va_range = VirtAddrRange::new(start_addr, end_addr);
+
+    let mut shm_manager = SHM_MANAGER.lock();
+    shm_manager.insert_shmid_vaddr(pid, shm_inner.shmid, start_addr);
+    info!(
+        "Process {} alloc shm virt addr start: {:#x}, size: {}, mapping_flags: {:#x?}",
+        pid,
+        start_addr.as_usize(),
+        length,
+        mapping_flags
+    );
+
+    // map the virtual address range to the physical address
+    if let Some(phys_pages) = shm_inner.phys_pages.clone() {
+        // Another proccess has attached the shared memory
+        // TODO(mivik): shm page size
+        let backend = Backend::new_shared(start_addr, phys_pages);
+        aspace.map(start_addr, length, mapping_flags, false, backend)?;
+    } else {
+        // This is the first process to attach the shared memory
+        let pages = Arc::new(SharedPages::new(length, PageSize::Size4K)?);
+        let backend = Backend::new_shared(start_addr, pages.clone());
+        aspace.map(start_addr, length, mapping_flags, false, backend)?;
+
+        shm_inner.map_to_phys(pages);
+    }
+
+    shm_inner.attach_process(pid, va_range);
+    Ok(start_addr.as_usize() as isize)
+}
+
+pub fn sys_shmctl(shmid: i32, cmd: u32, buf: UserPtr<ShmidDs>) -> AxResult<isize> {
+    let shm_inner = {
+        let shm_manager = SHM_MANAGER.lock();
+        shm_manager
+            .get_inner_by_shmid(shmid)
+            .ok_or(AxError::InvalidInput)?
+    };
+    let mut shm_inner = shm_inner.lock();
+
+    let cmd = cmd as i32;
+    if cmd == IPC_SET {
+        shm_inner.shmid_ds = *buf.get_as_mut()?;
+    } else if cmd == IPC_STAT {
+        if let Some(shmid_ds) = nullable!(buf.get_as_mut())? {
+            *shmid_ds = shm_inner.shmid_ds;
+        }
+    } else if cmd == IPC_RMID {
+        shm_inner.rmid = true;
+    } else {
+        return Err(AxError::InvalidInput);
+    }
+
+    shm_inner.shmid_ds.shm_ctime = monotonic_time_nanos() as __kernel_time_t;
+    Ok(0)
+}
+
+// Garbage collection for shared memory:
+// 1. when the process call sys_shmdt, delete everything related to shmaddr,
+//    including map 'shmid_vaddr';
+// 2. when the last process detach the shared memory and this shared memory was
+//    specified with IPC_RMID, delete everything related to this shared memory,
+//    including all the 3 maps;
+// 3. when a process exit, delete everything related to this process, including
+//    2 maps: 'shmid_vaddr' and 'shmid_inner';
+//
+// The attach between the process and the shared memory occurs in sys_shmat,
+//  and the detach occurs in sys_shmdt, or when the process exits.
+
+// Note: all the below delete functions only delete the mapping between the
+// shm_id and the shm_inner,   but the shm_inner is not deleted or modifyed!
+pub fn sys_shmdt(shmaddr: usize) -> AxResult<isize> {
+    let shmaddr = VirtAddr::from(shmaddr);
+
+    let curr = current();
+    let proc_data = &curr.as_thread().proc_data;
+
+    let pid = proc_data.proc.pid();
+    let shmid = {
+        let shm_manager = SHM_MANAGER.lock();
+        shm_manager
+            .get_shmid_by_vaddr(pid, shmaddr)
+            .ok_or(AxError::InvalidInput)?
+    };
+
+    let shm_inner = {
+        let shm_manager = SHM_MANAGER.lock();
+        shm_manager
+            .get_inner_by_shmid(shmid)
+            .ok_or(AxError::InvalidInput)?
+    };
+    let mut shm_inner = shm_inner.lock();
+    let va_range = shm_inner.get_addr_range(pid).ok_or(AxError::InvalidInput)?;
+
+    let mut aspace = proc_data.aspace.lock();
+    aspace.unmap(va_range.start, va_range.size())?;
+
+    let mut shm_manager = SHM_MANAGER.lock();
+    shm_manager.remove_shmaddr(pid, shmaddr);
+    shm_inner.detach_process(pid);
+
+    if shm_inner.rmid && shm_inner.attach_count() == 0 {
+        shm_manager.remove_shmid(shmid);
+    }
+
+    Ok(0)
+}
diff --git a/api/src/syscall/mm/brk.rs b/kernel/src/syscall/mm/brk.rs
similarity index 99%
rename from api/src/syscall/mm/brk.rs
rename to kernel/src/syscall/mm/brk.rs
index 178d57d7..55720ede 100644
--- a/api/src/syscall/mm/brk.rs
+++ b/kernel/src/syscall/mm/brk.rs
@@ -3,7 +3,8 @@ use axhal::paging::{MappingFlags, PageSize};
 use axmm::backend::Backend;
 use axtask::current;
 use memory_addr::{VirtAddr, align_up_4k};
-use starry_core::{
+
+use crate::{
     config::{USER_HEAP_BASE, USER_HEAP_SIZE, USER_HEAP_SIZE_MAX},
     task::AsThread,
 };
diff --git a/api/src/syscall/mm/mincore.rs b/kernel/src/syscall/mm/mincore.rs
similarity index 99%
rename from api/src/syscall/mm/mincore.rs
rename to kernel/src/syscall/mm/mincore.rs
index 6a6c112e..eea343d4 100644
--- a/api/src/syscall/mm/mincore.rs
+++ b/kernel/src/syscall/mm/mincore.rs
@@ -12,9 +12,10 @@ use axerrno::{AxError, AxResult};
 use axhal::paging::MappingFlags;
 use axtask::current;
 use memory_addr::{MemoryAddr, PAGE_SIZE_4K, VirtAddr};
-use starry_core::task::AsThread;
 use starry_vm::vm_write_slice;
 
+use crate::task::AsThread;
+
 /// Check whether pages are resident in memory.
 ///
 /// The mincore() system call determines whether pages of the calling process's
diff --git a/api/src/syscall/mm/mmap.rs b/kernel/src/syscall/mm/mmap.rs
similarity index 99%
rename from api/src/syscall/mm/mmap.rs
rename to kernel/src/syscall/mm/mmap.rs
index 94793882..dbb56ec6 100644
--- a/api/src/syscall/mm/mmap.rs
+++ b/kernel/src/syscall/mm/mmap.rs
@@ -7,13 +7,13 @@ use axmm::backend::{Backend, SharedPages};
 use axtask::current;
 use linux_raw_sys::general::*;
 use memory_addr::{MemoryAddr, VirtAddr, VirtAddrRange, align_up_4k};
-use starry_core::{
-    task::AsThread,
-    vfs::{Device, DeviceMmap},
-};
 use starry_vm::{vm_load, vm_write_slice};
 
-use crate::file::{File, FileLike};
+use crate::{
+    file::{File, FileLike},
+    task::AsThread,
+    pseudofs::{Device, DeviceMmap},
+};
 
 bitflags::bitflags! {
     /// `PROT_*` flags for use with [`sys_mmap`].
diff --git a/api/src/syscall/mm/mod.rs b/kernel/src/syscall/mm/mod.rs
similarity index 100%
rename from api/src/syscall/mm/mod.rs
rename to kernel/src/syscall/mm/mod.rs
diff --git a/api/src/syscall/mod.rs b/kernel/src/syscall/mod.rs
similarity index 99%
rename from api/src/syscall/mod.rs
rename to kernel/src/syscall/mod.rs
index 29c13b51..08cfde2c 100644
--- a/api/src/syscall/mod.rs
+++ b/kernel/src/syscall/mod.rs
@@ -14,7 +14,7 @@ use axerrno::{AxError, LinuxError};
 use axhal::uspace::UserContext;
 use syscalls::Sysno;
 
-use self::{
+pub use self::{
     fs::*, io_mpx::*, ipc::*, mm::*, net::*, resources::*, signal::*, sync::*, sys::*, task::*,
     time::*,
 };
diff --git a/api/src/socket.rs b/kernel/src/syscall/net/addr.rs
similarity index 99%
rename from api/src/socket.rs
rename to kernel/src/syscall/net/addr.rs
index 6c502fa7..4a3a5e0a 100644
--- a/api/src/socket.rs
+++ b/kernel/src/syscall/net/addr.rs
@@ -27,6 +27,7 @@ pub trait SocketAddrExt: Sized {
     fn write_to_user(&self, addr: UserPtr<sockaddr>, addrlen: &mut socklen_t) -> AxResult<()>;
 
     /// Gets the address family of the socket address.
+    #[allow(dead_code)]
     fn family(&self) -> u16;
 }
 
diff --git a/api/src/syscall/net/cmsg.rs b/kernel/src/syscall/net/cmsg.rs
similarity index 100%
rename from api/src/syscall/net/cmsg.rs
rename to kernel/src/syscall/net/cmsg.rs
diff --git a/api/src/syscall/net/io.rs b/kernel/src/syscall/net/io.rs
similarity index 97%
rename from api/src/syscall/net/io.rs
rename to kernel/src/syscall/net/io.rs
index 8ab55e45..b8949da9 100644
--- a/api/src/syscall/net/io.rs
+++ b/kernel/src/syscall/net/io.rs
@@ -8,11 +8,10 @@ use linux_raw_sys::net::{
     MSG_PEEK, MSG_TRUNC, SCM_RIGHTS, SOL_SOCKET, cmsghdr, msghdr, sockaddr, socklen_t,
 };
 
+use super::addr::SocketAddrExt;
 use crate::{
     file::{FileLike, Socket, add_file_like},
-    io::{IoVec, IoVectorBuf},
-    mm::{UserConstPtr, UserPtr, VmBytes, VmBytesMut},
-    socket::SocketAddrExt,
+    mm::{IoVec, IoVectorBuf, UserConstPtr, UserPtr, VmBytes, VmBytesMut},
     syscall::net::{CMsg, CMsgBuilder},
 };
 
diff --git a/api/src/syscall/net/mod.rs b/kernel/src/syscall/net/mod.rs
similarity index 91%
rename from api/src/syscall/net/mod.rs
rename to kernel/src/syscall/net/mod.rs
index eaa3ae59..1e2c43ce 100644
--- a/api/src/syscall/net/mod.rs
+++ b/kernel/src/syscall/net/mod.rs
@@ -1,3 +1,4 @@
+mod addr;
 mod cmsg;
 mod io;
 mod name;
diff --git a/api/src/syscall/net/name.rs b/kernel/src/syscall/net/name.rs
similarity index 96%
rename from api/src/syscall/net/name.rs
rename to kernel/src/syscall/net/name.rs
index 411b14cd..71bc7d1a 100644
--- a/api/src/syscall/net/name.rs
+++ b/kernel/src/syscall/net/name.rs
@@ -2,10 +2,10 @@ use axerrno::AxResult;
 use axnet::SocketOps;
 use linux_raw_sys::net::{sockaddr, socklen_t};
 
+use super::addr::SocketAddrExt;
 use crate::{
     file::{FileLike, Socket},
     mm::UserPtr,
-    socket::SocketAddrExt,
 };
 
 pub fn sys_getsockname(
diff --git a/api/src/syscall/net/opt.rs b/kernel/src/syscall/net/opt.rs
similarity index 100%
rename from api/src/syscall/net/opt.rs
rename to kernel/src/syscall/net/opt.rs
diff --git a/api/src/syscall/net/socket.rs b/kernel/src/syscall/net/socket.rs
similarity index 98%
rename from api/src/syscall/net/socket.rs
rename to kernel/src/syscall/net/socket.rs
index b8ebc904..26ba477f 100644
--- a/api/src/syscall/net/socket.rs
+++ b/kernel/src/syscall/net/socket.rs
@@ -15,12 +15,12 @@ use linux_raw_sys::{
         SOCK_DGRAM, SOCK_SEQPACKET, SOCK_STREAM, sockaddr, socklen_t,
     },
 };
-use starry_core::task::AsThread;
 
+use super::addr::SocketAddrExt;
 use crate::{
     file::{FileLike, Socket},
     mm::{UserConstPtr, UserPtr},
-    socket::SocketAddrExt,
+    task::AsThread,
 };
 
 pub fn sys_socket(domain: u32, raw_ty: u32, proto: u32) -> AxResult<isize> {
diff --git a/api/src/syscall/resources.rs b/kernel/src/syscall/resources.rs
similarity index 97%
rename from api/src/syscall/resources.rs
rename to kernel/src/syscall/resources.rs
index 8bf4ce35..3c9f4fed 100644
--- a/api/src/syscall/resources.rs
+++ b/kernel/src/syscall/resources.rs
@@ -2,11 +2,13 @@ use axerrno::{AxError, AxResult};
 use axhal::time::TimeValue;
 use axtask::current;
 use linux_raw_sys::general::{__kernel_old_timeval, RLIM_NLIMITS, rlimit64, rusage};
-use starry_core::task::{AsThread, Thread, get_process_data, get_task};
 use starry_process::Pid;
 use starry_vm::{VmMutPtr, VmPtr};
 
-use crate::time::TimeValueLike;
+use crate::{
+    task::{AsThread, Thread, get_process_data, get_task},
+    time::TimeValueLike,
+};
 
 pub fn sys_prlimit64(
     pid: Pid,
diff --git a/api/src/syscall/signal.rs b/kernel/src/syscall/signal.rs
similarity index 97%
rename from api/src/syscall/signal.rs
rename to kernel/src/syscall/signal.rs
index 3914be97..bccdbb70 100644
--- a/api/src/syscall/signal.rs
+++ b/kernel/src/syscall/signal.rs
@@ -10,16 +10,15 @@ use linux_raw_sys::general::{
     MINSIGSTKSZ, SI_TKILL, SI_USER, SIG_BLOCK, SIG_SETMASK, SIG_UNBLOCK, kernel_sigaction, siginfo,
     timespec,
 };
-use starry_core::task::{
-    AsThread, processes, send_signal_to_process, send_signal_to_process_group,
-    send_signal_to_thread,
-};
 use starry_process::Pid;
 use starry_signal::{SignalInfo, SignalSet, SignalStack, Signo};
 use starry_vm::{VmMutPtr, VmPtr};
 
 use crate::{
-    signal::{block_next_signal, check_signals},
+    task::{
+        AsThread, block_next_signal, check_signals, processes, send_signal_to_process,
+        send_signal_to_process_group, send_signal_to_thread,
+    },
     time::TimeValueLike,
 };
 
diff --git a/api/src/syscall/sync/futex.rs b/kernel/src/syscall/sync/futex.rs
similarity index 92%
rename from api/src/syscall/sync/futex.rs
rename to kernel/src/syscall/sync/futex.rs
index 30ec6107..129abbcc 100644
--- a/api/src/syscall/sync/futex.rs
+++ b/kernel/src/syscall/sync/futex.rs
@@ -6,13 +6,12 @@ use linux_raw_sys::general::{
     FUTEX_CMD_MASK, FUTEX_CMP_REQUEUE, FUTEX_REQUEUE, FUTEX_WAIT, FUTEX_WAIT_BITSET, FUTEX_WAKE,
     FUTEX_WAKE_BITSET, robust_list_head, timespec,
 };
-use starry_core::{
-    futex::FutexKey,
-    task::{AsThread, get_task},
-};
 use starry_vm::{VmMutPtr, VmPtr};
 
-use crate::time::TimeValueLike;
+use crate::{
+    task::{AsThread, FutexKey, futex_table_for, get_task},
+    time::TimeValueLike,
+};
 
 fn assert_unsigned(value: u32) -> AxResult<u32> {
     if (value as i32) < 0 {
@@ -37,10 +36,7 @@ pub fn sys_futex(
 
     let key = FutexKey::new_current(uaddr.addr());
 
-    let curr = current();
-    let thr = curr.as_thread();
-    let proc_data = &thr.proc_data;
-    let futex_table = proc_data.futex_table_for(&key);
+    let futex_table = futex_table_for(&key);
 
     let command = futex_op & (FUTEX_CMD_MASK as u32);
     match command {
@@ -102,7 +98,7 @@ pub fn sys_futex(
 
             let futex = futex_table.get(&key);
             let key2 = FutexKey::new_current(uaddr2.addr());
-            let table2 = proc_data.futex_table_for(&key2);
+            let table2 = futex_table_for(&key2);
             let futex2 = table2.get_or_insert(&key2);
 
             let mut count = 0;
diff --git a/api/src/syscall/sync/membarrier.rs b/kernel/src/syscall/sync/membarrier.rs
similarity index 100%
rename from api/src/syscall/sync/membarrier.rs
rename to kernel/src/syscall/sync/membarrier.rs
diff --git a/api/src/syscall/sync/mod.rs b/kernel/src/syscall/sync/mod.rs
similarity index 100%
rename from api/src/syscall/sync/mod.rs
rename to kernel/src/syscall/sync/mod.rs
diff --git a/api/src/syscall/sys.rs b/kernel/src/syscall/sys.rs
similarity index 98%
rename from api/src/syscall/sys.rs
rename to kernel/src/syscall/sys.rs
index 12e3cbba..572054b1 100644
--- a/api/src/syscall/sys.rs
+++ b/kernel/src/syscall/sys.rs
@@ -8,9 +8,10 @@ use linux_raw_sys::{
     general::{GRND_INSECURE, GRND_NONBLOCK, GRND_RANDOM},
     system::{new_utsname, sysinfo},
 };
-use starry_core::task::processes;
 use starry_vm::{VmMutPtr, vm_write_slice};
 
+use crate::task::processes;
+
 pub fn sys_getuid() -> AxResult<isize> {
     Ok(0)
 }
diff --git a/api/src/syscall/task/clone.rs b/kernel/src/syscall/task/clone.rs
similarity index 98%
rename from api/src/syscall/task/clone.rs
rename to kernel/src/syscall/task/clone.rs
index af91a761..250aa195 100644
--- a/api/src/syscall/task/clone.rs
+++ b/kernel/src/syscall/task/clone.rs
@@ -7,17 +7,14 @@ use axtask::{AxTaskExt, current, spawn_task};
 use bitflags::bitflags;
 use kspin::SpinNoIrq;
 use linux_raw_sys::general::*;
-use starry_core::{
-    mm::copy_from_kernel,
-    task::{AsThread, ProcessData, Thread, add_task_to_table},
-};
 use starry_process::Pid;
 use starry_signal::Signo;
 use starry_vm::VmMutPtr;
 
 use crate::{
     file::{FD_TABLE, FileLike, PidFd},
-    task::new_user_task,
+    mm::copy_from_kernel,
+    task::{AsThread, ProcessData, Thread, add_task_to_table, new_user_task},
 };
 
 bitflags! {
diff --git a/api/src/syscall/task/ctl.rs b/kernel/src/syscall/task/ctl.rs
similarity index 97%
rename from api/src/syscall/task/ctl.rs
rename to kernel/src/syscall/task/ctl.rs
index 5142097c..25d08872 100644
--- a/api/src/syscall/task/ctl.rs
+++ b/kernel/src/syscall/task/ctl.rs
@@ -3,10 +3,12 @@ use core::ffi::c_char;
 use axerrno::{AxError, AxResult};
 use axtask::current;
 use linux_raw_sys::general::{__user_cap_data_struct, __user_cap_header_struct};
-use starry_core::task::{AsThread, get_process_data};
 use starry_vm::{VmMutPtr, VmPtr, vm_write_slice};
 
-use crate::mm::vm_load_string;
+use crate::{
+    mm::vm_load_string,
+    task::{AsThread, get_process_data},
+};
 
 const CAPABILITY_VERSION_3: u32 = 0x20080522;
 
diff --git a/api/src/syscall/task/execve.rs b/kernel/src/syscall/task/execve.rs
similarity index 94%
rename from api/src/syscall/task/execve.rs
rename to kernel/src/syscall/task/execve.rs
index ba81dac1..bda86ab2 100644
--- a/api/src/syscall/task/execve.rs
+++ b/kernel/src/syscall/task/execve.rs
@@ -5,10 +5,14 @@ use axerrno::{AxError, AxResult};
 use axfs::FS_CONTEXT;
 use axhal::uspace::UserContext;
 use axtask::current;
-use starry_core::{config::USER_HEAP_BASE, mm::load_user_app, task::AsThread};
 use starry_vm::vm_load_until_nul;
 
-use crate::{file::FD_TABLE, mm::vm_load_string};
+use crate::{
+    config::USER_HEAP_BASE,
+    file::FD_TABLE,
+    mm::{load_user_app, vm_load_string},
+    task::AsThread,
+};
 
 pub fn sys_execve(
     uctx: &mut UserContext,
diff --git a/api/src/syscall/task/exit.rs b/kernel/src/syscall/task/exit.rs
similarity index 100%
rename from api/src/syscall/task/exit.rs
rename to kernel/src/syscall/task/exit.rs
diff --git a/api/src/syscall/task/job.rs b/kernel/src/syscall/task/job.rs
similarity index 93%
rename from api/src/syscall/task/job.rs
rename to kernel/src/syscall/task/job.rs
index bf267a85..db71aaf6 100644
--- a/api/src/syscall/task/job.rs
+++ b/kernel/src/syscall/task/job.rs
@@ -1,8 +1,9 @@
 use axerrno::{AxError, AxResult};
 use axtask::current;
-use starry_core::task::{AsThread, get_process_data, get_process_group};
 use starry_process::Pid;
 
+use crate::task::{AsThread, get_process_data, get_process_group};
+
 pub fn sys_getsid(pid: Pid) -> AxResult<isize> {
     Ok(get_process_data(pid)?.proc.group().session().sid() as _)
 }
diff --git a/api/src/syscall/task/mod.rs b/kernel/src/syscall/task/mod.rs
similarity index 100%
rename from api/src/syscall/task/mod.rs
rename to kernel/src/syscall/task/mod.rs
diff --git a/api/src/syscall/task/schedule.rs b/kernel/src/syscall/task/schedule.rs
similarity index 97%
rename from api/src/syscall/task/schedule.rs
rename to kernel/src/syscall/task/schedule.rs
index a7643585..6ccf647d 100644
--- a/api/src/syscall/task/schedule.rs
+++ b/kernel/src/syscall/task/schedule.rs
@@ -8,10 +8,12 @@ use linux_raw_sys::general::{
     __kernel_clockid_t, CLOCK_MONOTONIC, CLOCK_REALTIME, PRIO_PGRP, PRIO_PROCESS, PRIO_USER,
     SCHED_RR, TIMER_ABSTIME, timespec,
 };
-use starry_core::task::{get_process_data, get_process_group};
 use starry_vm::{VmMutPtr, VmPtr, vm_load, vm_write_slice};
 
-use crate::time::TimeValueLike;
+use crate::{
+    task::{get_process_data, get_process_group},
+    time::TimeValueLike,
+};
 
 pub fn sys_sched_yield() -> AxResult<isize> {
     axtask::yield_now();
diff --git a/api/src/syscall/task/thread.rs b/kernel/src/syscall/task/thread.rs
similarity index 98%
rename from api/src/syscall/task/thread.rs
rename to kernel/src/syscall/task/thread.rs
index 7d360fc2..fdfec9dc 100644
--- a/api/src/syscall/task/thread.rs
+++ b/kernel/src/syscall/task/thread.rs
@@ -1,6 +1,7 @@
 use axerrno::{AxError, AxResult};
 use axtask::current;
-use starry_core::task::AsThread;
+
+use crate::task::AsThread;
 
 pub fn sys_getpid() -> AxResult<isize> {
     Ok(current().as_thread().proc_data.proc.pid() as _)
diff --git a/api/src/syscall/task/wait.rs b/kernel/src/syscall/task/wait.rs
similarity index 99%
rename from api/src/syscall/task/wait.rs
rename to kernel/src/syscall/task/wait.rs
index 589c17bf..bf7fa8d1 100644
--- a/api/src/syscall/task/wait.rs
+++ b/kernel/src/syscall/task/wait.rs
@@ -10,10 +10,11 @@ use bitflags::bitflags;
 use linux_raw_sys::general::{
     __WALL, __WCLONE, __WNOTHREAD, WCONTINUED, WEXITED, WNOHANG, WNOWAIT, WUNTRACED,
 };
-use starry_core::task::AsThread;
 use starry_process::{Pid, Process};
 use starry_vm::{VmMutPtr, VmPtr};
 
+use crate::task::AsThread;
+
 bitflags! {
     #[derive(Debug)]
     struct WaitOptions: u32 {
diff --git a/api/src/syscall/time.rs b/kernel/src/syscall/time.rs
similarity index 97%
rename from api/src/syscall/time.rs
rename to kernel/src/syscall/time.rs
index 8ddf9a4d..289ab815 100644
--- a/api/src/syscall/time.rs
+++ b/kernel/src/syscall/time.rs
@@ -6,10 +6,12 @@ use linux_raw_sys::general::{
     CLOCK_MONOTONIC_RAW, CLOCK_PROCESS_CPUTIME_ID, CLOCK_REALTIME, CLOCK_REALTIME_COARSE,
     CLOCK_THREAD_CPUTIME_ID, itimerval, timespec, timeval,
 };
-use starry_core::{task::AsThread, time::ITimerType};
 use starry_vm::{VmMutPtr, VmPtr};
 
-use crate::time::TimeValueLike;
+use crate::{
+    task::{AsThread, ITimerType},
+    time::TimeValueLike,
+};
 
 pub fn sys_clock_gettime(clock_id: __kernel_clockid_t, ts: *mut timespec) -> AxResult<isize> {
     let now = match clock_id as u32 {
diff --git a/core/src/futex.rs b/kernel/src/task/futex.rs
similarity index 83%
rename from core/src/futex.rs
rename to kernel/src/task/futex.rs
index 7fed925b..f43647df 100644
--- a/core/src/futex.rs
+++ b/kernel/src/task/futex.rs
@@ -1,7 +1,7 @@
 //! Futex implementation.
 
 use alloc::{
-    collections::vec_deque::VecDeque,
+    collections::{btree_map::BTreeMap, vec_deque::VecDeque},
     sync::{Arc, Weak},
     vec::Vec,
 };
@@ -240,3 +240,45 @@ impl Drop for FutexGuard<'_> {
         }
     }
 }
+
+struct FutexTables {
+    map: BTreeMap<usize, Arc<FutexTable>>,
+    operations: usize,
+}
+impl FutexTables {
+    const fn new() -> Self {
+        Self {
+            map: BTreeMap::new(),
+            operations: 0,
+        }
+    }
+
+    fn get_or_insert(&mut self, key: usize) -> Arc<FutexTable> {
+        self.operations += 1;
+        if self.operations == 100 {
+            self.operations = 0;
+            self.map
+                .retain(|_, table| Arc::strong_count(table) > 1 || !table.is_empty());
+        }
+        self.map
+            .entry(key)
+            .or_insert_with(|| Arc::new(FutexTable::new()))
+            .clone()
+    }
+}
+
+static SHARED_FUTEX_TABLES: Mutex<FutexTables> = Mutex::new(FutexTables::new());
+
+/// Returns the futex table for the given key.
+pub fn futex_table_for(key: &FutexKey) -> Arc<FutexTable> {
+    match key {
+        FutexKey::Private { .. } => current().as_thread().proc_data.futex_table.clone(),
+        FutexKey::Shared { region, .. } => {
+            let ptr = match region {
+                Ok(pages) => Weak::as_ptr(pages) as usize,
+                Err(key) => Weak::as_ptr(key) as usize,
+            };
+            SHARED_FUTEX_TABLES.lock().get_or_insert(ptr)
+        }
+    }
+}
diff --git a/core/src/task.rs b/kernel/src/task/mod.rs
similarity index 52%
rename from core/src/task.rs
rename to kernel/src/task/mod.rs
index 9b36b781..800cc1c7 100644
--- a/core/src/task.rs
+++ b/kernel/src/task/mod.rs
@@ -1,42 +1,34 @@
 //! User task management.
 
+mod futex;
+mod ops;
+mod resources;
+mod signal;
 mod stat;
+mod timer;
+mod user;
 
-use alloc::{
-    boxed::Box,
-    string::String,
-    sync::{Arc, Weak},
-    vec::Vec,
-};
+use alloc::{boxed::Box, string::String, sync::Arc, vec::Vec};
 use core::{
     cell::RefCell,
     ops::Deref,
     sync::atomic::{AtomicBool, AtomicI32, AtomicU32, AtomicUsize, Ordering},
 };
 
-use axerrno::{AxError, AxResult};
 use axmm::AddrSpace;
 use axpoll::PollSet;
 use axsync::{Mutex, spin::SpinNoIrq};
-use axtask::{AxTaskRef, TaskExt, TaskInner, WeakAxTaskRef, current};
+use axtask::{TaskExt, TaskInner};
 use extern_trait::extern_trait;
-use hashbrown::HashMap;
-use lazy_static::lazy_static;
 use scope_local::{ActiveScope, Scope};
 use spin::RwLock;
-use starry_process::{Pid, Process, ProcessGroup, Session};
+use starry_process::Process;
 use starry_signal::{
-    SignalInfo, Signo,
+    Signo,
     api::{ProcessSignalManager, SignalActions, ThreadSignalManager},
 };
-use weak_map::WeakMap;
 
-pub use self::stat::TaskStat;
-use crate::{
-    futex::{FutexKey, FutexTable},
-    resources::Rlimits,
-    time::{TimeManager, TimerState},
-};
+pub use self::{futex::*, ops::*, resources::*, signal::*, stat::*, timer::*, user::*};
 
 ///  A wrapper type that assumes the inner type is `Sync`.
 #[repr(transparent)]
@@ -275,20 +267,6 @@ impl ProcessData {
         self.exit_signal != Some(Signo::SIGCHLD)
     }
 
-    /// Returns the futex table for the given key.
-    pub fn futex_table_for(&self, key: &FutexKey) -> Arc<FutexTable> {
-        match key {
-            FutexKey::Private { .. } => self.futex_table.clone(),
-            FutexKey::Shared { region, .. } => {
-                let ptr = match region {
-                    Ok(pages) => Weak::as_ptr(pages) as usize,
-                    Err(key) => Weak::as_ptr(key) as usize,
-                };
-                SHARED_FUTEX_TABLES.lock().get_or_insert(ptr)
-            }
-        }
-    }
-
     /// Get the umask.
     pub fn umask(&self) -> u32 {
         self.umask.load(Ordering::SeqCst)
@@ -304,205 +282,3 @@ impl ProcessData {
         self.umask.swap(umask, Ordering::SeqCst)
     }
 }
-
-struct FutexTables {
-    map: HashMap<usize, Arc<FutexTable>>,
-    operations: usize,
-}
-impl FutexTables {
-    fn new() -> Self {
-        Self {
-            map: HashMap::new(),
-            operations: 0,
-        }
-    }
-
-    fn get_or_insert(&mut self, key: usize) -> Arc<FutexTable> {
-        self.operations += 1;
-        if self.operations == 100 {
-            self.operations = 0;
-            self.map
-                .retain(|_, table| Arc::strong_count(table) > 1 || !table.is_empty());
-        }
-        self.map
-            .entry(key)
-            .or_insert_with(|| Arc::new(FutexTable::new()))
-            .clone()
-    }
-}
-
-lazy_static! {
-    static ref SHARED_FUTEX_TABLES: Mutex<FutexTables> = Mutex::new(FutexTables::new());
-}
-
-static TASK_TABLE: RwLock<WeakMap<Pid, WeakAxTaskRef>> = RwLock::new(WeakMap::new());
-
-static PROCESS_TABLE: RwLock<WeakMap<Pid, Weak<ProcessData>>> = RwLock::new(WeakMap::new());
-
-static PROCESS_GROUP_TABLE: RwLock<WeakMap<Pid, Weak<ProcessGroup>>> = RwLock::new(WeakMap::new());
-
-static SESSION_TABLE: RwLock<WeakMap<Pid, Weak<Session>>> = RwLock::new(WeakMap::new());
-
-/// Cleanup expired entries in the task tables.
-///
-/// This function is intended to be used during memory leak analysis to remove
-/// possible noise caused by expired entries in the [`WeakMap`].
-pub fn cleanup_task_tables() {
-    TASK_TABLE.write().cleanup();
-    PROCESS_TABLE.write().cleanup();
-    PROCESS_GROUP_TABLE.write().cleanup();
-    SESSION_TABLE.write().cleanup();
-}
-
-/// Add the task, the thread and possibly its process, process group and session
-/// to the corresponding tables.
-pub fn add_task_to_table(task: &AxTaskRef) {
-    let tid = task.id().as_u64() as Pid;
-
-    let mut task_table = TASK_TABLE.write();
-    task_table.insert(tid, task);
-
-    let proc_data = &task.as_thread().proc_data;
-    let proc = &proc_data.proc;
-    let pid = proc.pid();
-    let mut proc_table = PROCESS_TABLE.write();
-    if proc_table.contains_key(&pid) {
-        return;
-    }
-    proc_table.insert(pid, proc_data);
-
-    let pg = proc.group();
-    let mut pg_table = PROCESS_GROUP_TABLE.write();
-    if pg_table.contains_key(&pg.pgid()) {
-        return;
-    }
-    pg_table.insert(pg.pgid(), &pg);
-
-    let session = pg.session();
-    let mut session_table = SESSION_TABLE.write();
-    if session_table.contains_key(&session.sid()) {
-        return;
-    }
-    session_table.insert(session.sid(), &session);
-}
-
-/// Lists all tasks.
-pub fn tasks() -> Vec<AxTaskRef> {
-    TASK_TABLE.read().values().collect()
-}
-
-/// Finds the task with the given TID.
-pub fn get_task(tid: Pid) -> AxResult<AxTaskRef> {
-    if tid == 0 {
-        return Ok(current().clone());
-    }
-    TASK_TABLE.read().get(&tid).ok_or(AxError::NoSuchProcess)
-}
-
-/// Lists all processes.
-pub fn processes() -> Vec<Arc<ProcessData>> {
-    PROCESS_TABLE.read().values().collect()
-}
-
-/// Finds the process with the given PID.
-pub fn get_process_data(pid: Pid) -> AxResult<Arc<ProcessData>> {
-    if pid == 0 {
-        return Ok(current().as_thread().proc_data.clone());
-    }
-    PROCESS_TABLE.read().get(&pid).ok_or(AxError::NoSuchProcess)
-}
-
-/// Finds the process group with the given PGID.
-pub fn get_process_group(pgid: Pid) -> AxResult<Arc<ProcessGroup>> {
-    PROCESS_GROUP_TABLE
-        .read()
-        .get(&pgid)
-        .ok_or(AxError::NoSuchProcess)
-}
-
-/// Finds the session with the given SID.
-pub fn get_session(sid: Pid) -> AxResult<Arc<Session>> {
-    SESSION_TABLE.read().get(&sid).ok_or(AxError::NoSuchProcess)
-}
-
-/// Poll the timer
-pub fn poll_timer(task: &TaskInner) {
-    let Some(thr) = task.try_as_thread() else {
-        return;
-    };
-    let Ok(mut time) = thr.time.try_borrow_mut() else {
-        // reentrant borrow, likely IRQ
-        return;
-    };
-    time.poll(|signo| {
-        send_signal_thread_inner(task, thr, SignalInfo::new_kernel(signo));
-    });
-}
-
-/// Sets the timer state.
-pub fn set_timer_state(task: &TaskInner, state: TimerState) {
-    let Some(thr) = task.try_as_thread() else {
-        return;
-    };
-    let Ok(mut time) = thr.time.try_borrow_mut() else {
-        // reentrant borrow, likely IRQ
-        return;
-    };
-    time.poll(|signo| {
-        send_signal_thread_inner(task, thr, SignalInfo::new_kernel(signo));
-    });
-    time.set_state(state);
-}
-
-fn send_signal_thread_inner(task: &TaskInner, thr: &Thread, sig: SignalInfo) {
-    if thr.signal.send_signal(sig) {
-        task.interrupt();
-    }
-}
-
-/// Sends a signal to a thread.
-pub fn send_signal_to_thread(tgid: Option<Pid>, tid: Pid, sig: Option<SignalInfo>) -> AxResult<()> {
-    let task = get_task(tid)?;
-    let thread = task.try_as_thread().ok_or(AxError::OperationNotPermitted)?;
-    if tgid.is_some_and(|tgid| thread.proc_data.proc.pid() != tgid) {
-        return Err(AxError::NoSuchProcess);
-    }
-
-    if let Some(sig) = sig {
-        info!("Send signal {:?} to thread {}", sig.signo(), tid);
-        send_signal_thread_inner(&task, thread, sig);
-    }
-
-    Ok(())
-}
-
-/// Sends a signal to a process.
-pub fn send_signal_to_process(pid: Pid, sig: Option<SignalInfo>) -> AxResult<()> {
-    let proc_data = get_process_data(pid)?;
-
-    if let Some(sig) = sig {
-        let signo = sig.signo();
-        info!("Send signal {signo:?} to process {pid}");
-        if let Some(tid) = proc_data.signal.send_signal(sig)
-            && let Ok(task) = get_task(tid)
-        {
-            task.interrupt();
-        }
-    }
-
-    Ok(())
-}
-
-/// Sends a signal to a process group.
-pub fn send_signal_to_process_group(pgid: Pid, sig: Option<SignalInfo>) -> AxResult<()> {
-    let pg = get_process_group(pgid)?;
-
-    if let Some(sig) = sig {
-        info!("Send signal {:?} to process group {}", sig.signo(), pgid);
-        for proc in pg.processes() {
-            send_signal_to_process(proc.pid(), Some(sig.clone()))?;
-        }
-    }
-
-    Ok(())
-}
diff --git a/kernel/src/task/ops.rs b/kernel/src/task/ops.rs
new file mode 100644
index 00000000..81e9286a
--- /dev/null
+++ b/kernel/src/task/ops.rs
@@ -0,0 +1,248 @@
+use alloc::{
+    sync::{Arc, Weak},
+    vec::Vec,
+};
+use core::{ffi::c_long, sync::atomic::Ordering};
+
+use axerrno::{AxError, AxResult};
+use axtask::{AxTaskRef, TaskInner, WeakAxTaskRef, current};
+use bytemuck::AnyBitPattern;
+use linux_raw_sys::general::ROBUST_LIST_LIMIT;
+use spin::RwLock;
+use starry_process::{Pid, ProcessGroup, Session};
+use starry_signal::{SignalInfo, Signo};
+use starry_vm::{VmMutPtr, VmPtr};
+use weak_map::WeakMap;
+
+use super::{
+    AsThread, FutexKey, ProcessData, TimerState, futex_table_for, send_signal_thread_inner,
+    send_signal_to_process, send_signal_to_thread,
+};
+
+static TASK_TABLE: RwLock<WeakMap<Pid, WeakAxTaskRef>> = RwLock::new(WeakMap::new());
+
+static PROCESS_TABLE: RwLock<WeakMap<Pid, Weak<ProcessData>>> = RwLock::new(WeakMap::new());
+
+static PROCESS_GROUP_TABLE: RwLock<WeakMap<Pid, Weak<ProcessGroup>>> = RwLock::new(WeakMap::new());
+
+static SESSION_TABLE: RwLock<WeakMap<Pid, Weak<Session>>> = RwLock::new(WeakMap::new());
+
+/// Cleanup expired entries in the task tables.
+///
+/// This function is intended to be used during memory leak analysis to remove
+/// possible noise caused by expired entries in the [`WeakMap`].
+pub fn cleanup_task_tables() {
+    TASK_TABLE.write().cleanup();
+    PROCESS_TABLE.write().cleanup();
+    PROCESS_GROUP_TABLE.write().cleanup();
+    SESSION_TABLE.write().cleanup();
+}
+
+/// Add the task, the thread and possibly its process, process group and session
+/// to the corresponding tables.
+pub fn add_task_to_table(task: &AxTaskRef) {
+    let tid = task.id().as_u64() as Pid;
+
+    let mut task_table = TASK_TABLE.write();
+    task_table.insert(tid, task);
+
+    let proc_data = &task.as_thread().proc_data;
+    let proc = &proc_data.proc;
+    let pid = proc.pid();
+    let mut proc_table = PROCESS_TABLE.write();
+    if proc_table.contains_key(&pid) {
+        return;
+    }
+    proc_table.insert(pid, proc_data);
+
+    let pg = proc.group();
+    let mut pg_table = PROCESS_GROUP_TABLE.write();
+    if pg_table.contains_key(&pg.pgid()) {
+        return;
+    }
+    pg_table.insert(pg.pgid(), &pg);
+
+    let session = pg.session();
+    let mut session_table = SESSION_TABLE.write();
+    if session_table.contains_key(&session.sid()) {
+        return;
+    }
+    session_table.insert(session.sid(), &session);
+}
+
+/// Lists all tasks.
+pub fn tasks() -> Vec<AxTaskRef> {
+    TASK_TABLE.read().values().collect()
+}
+
+/// Finds the task with the given TID.
+pub fn get_task(tid: Pid) -> AxResult<AxTaskRef> {
+    if tid == 0 {
+        return Ok(current().clone());
+    }
+    TASK_TABLE.read().get(&tid).ok_or(AxError::NoSuchProcess)
+}
+
+/// Lists all processes.
+pub fn processes() -> Vec<Arc<ProcessData>> {
+    PROCESS_TABLE.read().values().collect()
+}
+
+/// Finds the process with the given PID.
+pub fn get_process_data(pid: Pid) -> AxResult<Arc<ProcessData>> {
+    if pid == 0 {
+        return Ok(current().as_thread().proc_data.clone());
+    }
+    PROCESS_TABLE.read().get(&pid).ok_or(AxError::NoSuchProcess)
+}
+
+/// Finds the process group with the given PGID.
+pub fn get_process_group(pgid: Pid) -> AxResult<Arc<ProcessGroup>> {
+    PROCESS_GROUP_TABLE
+        .read()
+        .get(&pgid)
+        .ok_or(AxError::NoSuchProcess)
+}
+
+/// Finds the session with the given SID.
+pub fn get_session(sid: Pid) -> AxResult<Arc<Session>> {
+    SESSION_TABLE.read().get(&sid).ok_or(AxError::NoSuchProcess)
+}
+
+/// Poll the timer
+pub fn poll_timer(task: &TaskInner) {
+    let Some(thr) = task.try_as_thread() else {
+        return;
+    };
+    let Ok(mut time) = thr.time.try_borrow_mut() else {
+        // reentrant borrow, likely IRQ
+        return;
+    };
+    time.poll(|signo| {
+        send_signal_thread_inner(task, thr, SignalInfo::new_kernel(signo));
+    });
+}
+
+/// Sets the timer state.
+pub fn set_timer_state(task: &TaskInner, state: TimerState) {
+    let Some(thr) = task.try_as_thread() else {
+        return;
+    };
+    let Ok(mut time) = thr.time.try_borrow_mut() else {
+        // reentrant borrow, likely IRQ
+        return;
+    };
+    time.poll(|signo| {
+        send_signal_thread_inner(task, thr, SignalInfo::new_kernel(signo));
+    });
+    time.set_state(state);
+}
+
+#[repr(C)]
+#[derive(Debug, Copy, Clone, AnyBitPattern)]
+pub struct RobustList {
+    pub next: *mut RobustList,
+}
+
+#[repr(C)]
+#[derive(Debug, Copy, Clone, AnyBitPattern)]
+pub struct RobustListHead {
+    pub list: RobustList,
+    pub futex_offset: c_long,
+    pub list_op_pending: *mut RobustList,
+}
+
+fn handle_futex_death(entry: *mut RobustList, offset: i64) -> AxResult<()> {
+    let address = (entry as u64)
+        .checked_add_signed(offset)
+        .ok_or(AxError::InvalidInput)?;
+    let address: usize = address.try_into().map_err(|_| AxError::InvalidInput)?;
+    let key = FutexKey::new_current(address);
+
+    let futex_table = futex_table_for(&key);
+
+    let Some(futex) = futex_table.get(&key) else {
+        return Ok(());
+    };
+    futex.owner_dead.store(true, Ordering::SeqCst);
+    futex.wq.wake(1, u32::MAX);
+    Ok(())
+}
+
+pub fn exit_robust_list(head: *const RobustListHead) -> AxResult<()> {
+    // Reference: https://elixir.bootlin.com/linux/v6.13.6/source/kernel/futex/core.c#L777
+
+    let mut limit = ROBUST_LIST_LIMIT;
+
+    let end_ptr = unsafe { &raw const (*head).list };
+    let head = head.vm_read()?;
+    let mut entry = head.list.next;
+    let offset = head.futex_offset;
+    let pending = head.list_op_pending;
+
+    while !core::ptr::eq(entry, end_ptr) {
+        let next_entry = entry.vm_read()?.next;
+        if entry != pending {
+            handle_futex_death(entry, offset)?;
+        }
+        entry = next_entry;
+
+        limit -= 1;
+        if limit == 0 {
+            return Err(AxError::FilesystemLoop);
+        }
+        axtask::yield_now();
+    }
+
+    Ok(())
+}
+
+pub fn do_exit(exit_code: i32, group_exit: bool) {
+    let curr = current();
+    let thr = curr.as_thread();
+
+    info!("{} exit with code: {}", curr.id_name(), exit_code);
+
+    let clear_child_tid = thr.clear_child_tid() as *mut u32;
+    if clear_child_tid.vm_write(0).is_ok() {
+        let key = FutexKey::new_current(clear_child_tid as usize);
+        let table = futex_table_for(&key);
+        let guard = table.get(&key);
+        if let Some(futex) = guard {
+            futex.wq.wake(1, u32::MAX);
+        }
+        axtask::yield_now();
+    }
+    let head = thr.robust_list_head() as *const RobustListHead;
+    if !head.is_null()
+        && let Err(err) = exit_robust_list(head)
+    {
+        warn!("exit robust list failed: {err:?}");
+    }
+
+    let process = &thr.proc_data.proc;
+    if process.exit_thread(curr.id().as_u64() as Pid, exit_code) {
+        process.exit();
+        if let Some(parent) = process.parent() {
+            if let Some(signo) = thr.proc_data.exit_signal {
+                let _ = send_signal_to_process(parent.pid(), Some(SignalInfo::new_kernel(signo)));
+            }
+            if let Ok(data) = get_process_data(parent.pid()) {
+                data.child_exit_event.wake();
+            }
+        }
+        thr.proc_data.exit_event.wake();
+
+        crate::syscall::SHM_MANAGER
+            .lock()
+            .clear_proc_shm(process.pid());
+    }
+    if group_exit && !process.is_group_exited() {
+        process.group_exit();
+        let sig = SignalInfo::new_kernel(Signo::SIGKILL);
+        for tid in process.threads() {
+            let _ = send_signal_to_thread(None, tid, Some(sig.clone()));
+        }
+    }
+    thr.set_exit();
+}
diff --git a/core/src/resources.rs b/kernel/src/task/resources.rs
similarity index 100%
rename from core/src/resources.rs
rename to kernel/src/task/resources.rs
diff --git a/kernel/src/task/signal.rs b/kernel/src/task/signal.rs
new file mode 100644
index 00000000..f0f15ade
--- /dev/null
+++ b/kernel/src/task/signal.rs
@@ -0,0 +1,138 @@
+use core::sync::atomic::{AtomicBool, Ordering};
+
+use axerrno::{AxError, AxResult};
+use axhal::uspace::UserContext;
+use axtask::{TaskInner, current};
+use starry_process::Pid;
+use starry_signal::{SignalInfo, SignalOSAction, SignalSet};
+
+use super::{AsThread, Thread, do_exit, get_process_data, get_process_group, get_task};
+
+pub fn check_signals(
+    thr: &Thread,
+    uctx: &mut UserContext,
+    restore_blocked: Option<SignalSet>,
+) -> bool {
+    let Some((sig, os_action)) = thr.signal.check_signals(uctx, restore_blocked) else {
+        return false;
+    };
+
+    let signo = sig.signo();
+    match os_action {
+        SignalOSAction::Terminate => {
+            do_exit(signo as i32, true);
+        }
+        SignalOSAction::CoreDump => {
+            // TODO: implement core dump
+            do_exit(128 + signo as i32, true);
+        }
+        SignalOSAction::Stop => {
+            // TODO: implement stop
+            do_exit(1, true);
+        }
+        SignalOSAction::Continue => {
+            // TODO: implement continue
+        }
+        SignalOSAction::Handler => {
+            // do nothing
+        }
+    }
+    true
+}
+
+static BLOCK_NEXT_SIGNAL_CHECK: AtomicBool = AtomicBool::new(false);
+
+pub fn block_next_signal() {
+    BLOCK_NEXT_SIGNAL_CHECK.store(true, Ordering::SeqCst);
+}
+
+pub fn unblock_next_signal() -> bool {
+    BLOCK_NEXT_SIGNAL_CHECK.swap(false, Ordering::SeqCst)
+}
+
+pub fn with_blocked_signals<R>(
+    blocked: Option<SignalSet>,
+    f: impl FnOnce() -> AxResult<R>,
+) -> AxResult<R> {
+    let curr = current();
+    let sig = &curr.as_thread().signal;
+
+    let old_blocked = blocked.map(|set| sig.set_blocked(set));
+    f().inspect(|_| {
+        if let Some(old) = old_blocked {
+            sig.set_blocked(old);
+        }
+    })
+}
+
+pub(super) fn send_signal_thread_inner(task: &TaskInner, thr: &Thread, sig: SignalInfo) {
+    if thr.signal.send_signal(sig) {
+        task.interrupt();
+    }
+}
+
+/// Sends a signal to a thread.
+pub fn send_signal_to_thread(tgid: Option<Pid>, tid: Pid, sig: Option<SignalInfo>) -> AxResult<()> {
+    let task = get_task(tid)?;
+    let thread = task.try_as_thread().ok_or(AxError::OperationNotPermitted)?;
+    if tgid.is_some_and(|tgid| thread.proc_data.proc.pid() != tgid) {
+        return Err(AxError::NoSuchProcess);
+    }
+
+    if let Some(sig) = sig {
+        info!("Send signal {:?} to thread {}", sig.signo(), tid);
+        send_signal_thread_inner(&task, thread, sig);
+    }
+
+    Ok(())
+}
+
+/// Sends a signal to a process.
+pub fn send_signal_to_process(pid: Pid, sig: Option<SignalInfo>) -> AxResult<()> {
+    let proc_data = get_process_data(pid)?;
+
+    if let Some(sig) = sig {
+        let signo = sig.signo();
+        info!("Send signal {signo:?} to process {pid}");
+        if let Some(tid) = proc_data.signal.send_signal(sig)
+            && let Ok(task) = get_task(tid)
+        {
+            task.interrupt();
+        }
+    }
+
+    Ok(())
+}
+
+/// Sends a signal to a process group.
+pub fn send_signal_to_process_group(pgid: Pid, sig: Option<SignalInfo>) -> AxResult<()> {
+    let pg = get_process_group(pgid)?;
+
+    if let Some(sig) = sig {
+        info!("Send signal {:?} to process group {}", sig.signo(), pgid);
+        for proc in pg.processes() {
+            send_signal_to_process(proc.pid(), Some(sig.clone()))?;
+        }
+    }
+
+    Ok(())
+}
+
+/// Sends a fatal signal to the current process.
+pub fn raise_signal_fatal(sig: SignalInfo) -> AxResult<()> {
+    let curr = current();
+    let proc_data = &curr.as_thread().proc_data;
+
+    let signo = sig.signo();
+    info!("Send fatal signal {signo:?} to the current process");
+    if let Some(tid) = proc_data.signal.send_signal(sig)
+        && let Ok(task) = get_task(tid)
+    {
+        task.interrupt();
+    } else {
+        // No task wants to handle the signal, abort the task
+        do_exit(signo as i32, true);
+    }
+
+    Ok(())
+}
diff --git a/core/src/task/stat.rs b/kernel/src/task/stat.rs
similarity index 100%
rename from core/src/task/stat.rs
rename to kernel/src/task/stat.rs
diff --git a/core/src/time.rs b/kernel/src/task/timer.rs
similarity index 100%
rename from core/src/time.rs
rename to kernel/src/task/timer.rs
diff --git a/kernel/src/task/user.rs b/kernel/src/task/user.rs
new file mode 100644
index 00000000..7b08673a
--- /dev/null
+++ b/kernel/src/task/user.rs
@@ -0,0 +1,79 @@
+use axhal::uspace::{ExceptionKind, ReturnReason, UserContext};
+use axtask::TaskInner;
+use starry_process::Pid;
+use starry_signal::{SignalInfo, Signo};
+use starry_vm::{VmMutPtr, VmPtr};
+
+use super::{
+    AsThread, TimerState, check_signals, raise_signal_fatal, set_timer_state, unblock_next_signal,
+};
+use crate::syscall::handle_syscall;
+
+/// Create a new user task.
+pub fn new_user_task(name: &str, mut uctx: UserContext, set_child_tid: usize) -> TaskInner {
+    TaskInner::new(
+        move || {
+            let curr = axtask::current();
+
+            if let Some(tid) = (set_child_tid as *mut Pid).nullable() {
+                tid.vm_write(curr.id().as_u64() as Pid).ok();
+            }
+
+            info!("Enter user space: ip={:#x}, sp={:#x}", uctx.ip(), uctx.sp());
+
+            let thr = curr.as_thread();
+            while !thr.pending_exit() {
+                let reason = uctx.run();
+
+                set_timer_state(&curr, TimerState::Kernel);
+
+                match reason {
+                    ReturnReason::Syscall => handle_syscall(&mut uctx),
+                    ReturnReason::PageFault(addr, flags) => {
+                        if !thr.proc_data.aspace.lock().handle_page_fault(addr, flags) {
+                            info!(
+                                "{:?}: segmentation fault at {:#x} {:?}",
+                                thr.proc_data.proc, addr, flags
+                            );
+                            raise_signal_fatal(SignalInfo::new_kernel(Signo::SIGSEGV))
+                                .expect("Failed to send SIGSEGV");
+                        }
+                    }
+                    ReturnReason::Interrupt => {}
+                    #[allow(unused_labels)]
+                    ReturnReason::Exception(exc_info) => 'exc: {
+                        // TODO: detailed handling
+                        let signo = match exc_info.kind() {
+                            ExceptionKind::Misaligned => {
+                                #[cfg(target_arch = "loongarch64")]
+                                if unsafe { uctx.emulate_unaligned() }.is_ok() {
+                                    break 'exc;
+                                }
+                                Signo::SIGBUS
+                            }
+                            ExceptionKind::Breakpoint => Signo::SIGTRAP,
+                            ExceptionKind::IllegalInstruction => Signo::SIGILL,
+                            _ => Signo::SIGTRAP,
+                        };
+                        raise_signal_fatal(SignalInfo::new_kernel(signo))
+                            .expect("Failed to send SIGTRAP");
+                    }
+                    r => {
+                        warn!("Unexpected return reason: {r:?}");
+                        raise_signal_fatal(SignalInfo::new_kernel(Signo::SIGSEGV))
+                            .expect("Failed to send SIGSEGV");
+                    }
+                }
+
+                if !unblock_next_signal() {
+                    while check_signals(thr, &mut uctx, None) {}
+                }
+
+                set_timer_state(&curr, TimerState::User);
+                curr.clear_interrupt();
+            }
+        },
+        name.into(),
+        crate::config::KERNEL_STACK_SIZE,
+    )
+}
diff --git a/api/src/time.rs b/kernel/src/time.rs
similarity index 93%
rename from api/src/time.rs
rename to kernel/src/time.rs
index 80164ee4..3d054f4d 100644
--- a/api/src/time.rs
+++ b/kernel/src/time.rs
@@ -1,5 +1,3 @@
-use core::sync::atomic::{AtomicUsize, Ordering};
-
 use axerrno::{AxError, AxResult};
 use axhal::time::TimeValue;
 use linux_raw_sys::general::{
@@ -130,13 +128,3 @@ impl TimeValueLike for __kernel_sock_timeval {
         ))
     }
 }
-
-static IRQ_CNT: AtomicUsize = AtomicUsize::new(0);
-
-pub(crate) fn inc_irq_cnt() {
-    IRQ_CNT.fetch_add(1, Ordering::Relaxed);
-}
-
-pub(crate) fn irq_cnt() -> usize {
-    IRQ_CNT.load(Ordering::Relaxed)
-}
diff --git a/src/entry.rs b/src/entry.rs
index 86fba54f..7dc7fd9c 100644
--- a/src/entry.rs
+++ b/src/entry.rs
@@ -7,10 +7,11 @@ use axfs::FS_CONTEXT;
 use axhal::uspace::UserContext;
 use axsync::Mutex;
 use axtask::{AxTaskExt, spawn_task};
-use starry_api::{file::FD_TABLE, task::new_user_task, vfs::dev::tty::N_TTY};
-use starry_core::{
+use starry_kernel::{
+    file::FD_TABLE,
     mm::{copy_from_kernel, load_user_app, new_user_aspace_empty},
-    task::{ProcessData, Thread, add_task_to_table},
+    pseudofs::dev::tty::N_TTY,
+    task::{ProcessData, Thread, add_task_to_table, new_user_task},
 };
 use starry_process::{Pid, Process};
 
@@ -55,7 +56,7 @@ pub fn run_initproc(args: &[String], envs: &[String]) -> i32 {
     );
     {
         let mut scope = proc_data.scope.write();
-        starry_api::file::add_stdio(&mut FD_TABLE.scope_mut(&mut scope).write())
+        starry_kernel::file::add_stdio(&mut FD_TABLE.scope_mut(&mut scope).write())
             .expect("Failed to add stdio");
     }
     let thr = Thread::new(pid, proc_data);
diff --git a/src/main.rs b/src/main.rs
index b88237cc..38dc2237 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -18,7 +18,7 @@ pub const CMDLINE: &[&str] = &["/bin/sh", "-c", include_str!("init.sh")];
 
 #[unsafe(no_mangle)]
 fn main() {
-    starry_api::init();
+    starry_kernel::init();
 
     let args = CMDLINE
         .iter()

From 9dd35dde486e6906d0411e3042bde1e442fc47a7 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E6=9C=9D=E5=80=89=E6=B0=B4=E5=B8=8C?=
 <asakuramizu111@gmail.com>
Date: Sun, 15 Feb 2026 23:03:34 +0800
Subject: [PATCH 2/2] style: format

---
 kernel/src/syscall/fs/fd_ops.rs | 2 +-
 kernel/src/syscall/mm/mmap.rs   | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/src/syscall/fs/fd_ops.rs b/kernel/src/syscall/fs/fd_ops.rs
index 44f0090d..32e6e7b7 100644
--- a/kernel/src/syscall/fs/fd_ops.rs
+++ b/kernel/src/syscall/fs/fd_ops.rs
@@ -18,9 +18,9 @@ use crate::{
         with_fs,
     },
     mm::{UserPtr, vm_load_string},
+    pseudofs::{Device, dev::tty},
     syscall::sys::{sys_getegid, sys_geteuid},
     task::AsThread,
-    pseudofs::{Device, dev::tty},
 };
 
 /// Convert open flags to [`OpenOptions`].
diff --git a/kernel/src/syscall/mm/mmap.rs b/kernel/src/syscall/mm/mmap.rs
index dbb56ec6..48574524 100644
--- a/kernel/src/syscall/mm/mmap.rs
+++ b/kernel/src/syscall/mm/mmap.rs
@@ -11,8 +11,8 @@ use starry_vm::{vm_load, vm_write_slice};
 
 use crate::{
     file::{File, FileLike},
-    task::AsThread,
     pseudofs::{Device, DeviceMmap},
+    task::AsThread,
 };
 
 bitflags::bitflags! {