Merge pull request 'feature/nikocs/smaller_init_system' (#6) from feature/nikocs/smaller_init_system into develop

Reviewed-on: #6

Cargo.toml

@@ -1,6 +1,6 @@
 [workspace]
 members = ["liblbos"]
-exclude = ["turntable", "makeddi", "ddi", "example"]
+exclude = ["blood", "turntable", "makeddi", "ddi", "example"]
 
 [package]
 name = "lbos"

blood/.gitignore

@@ -0,0 +1,2 @@
+/target
+/.idea

blood/Cargo.lock

@@ -0,0 +1,14 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 4
+
+[[package]]
+name = "blood"
+version = "0.1.0"
+dependencies = [
+ "liblbos",
+]
+
+[[package]]
+name = "liblbos"
+version = "0.1.1"

blood/Cargo.toml

@@ -0,0 +1,25 @@
+[package]
+name = "blood"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]
+liblbos = { path = "../liblbos" }
+
+[profile.dev]
+panic = "abort"
+opt-level = "s"
+debug-assertions = false
+overflow-checks = false
+
+[profile.release]
+panic = "abort"
+opt-level = "z"
+debug-assertions = false
+overflow-checks = false
+lto = true
+codegen-units = 1
+
+[features]
+default = ["arch_riscv32"]
+arch_riscv32 = ["liblbos/arch_riscv32"]

blood/build.rs

@@ -0,0 +1,16 @@
+fn main() {
+    let arch = std::env::var("LBOS_ARCH").unwrap_or("riscv32".to_string());
+    println!("cargo:rerun-if-env-changed=LBOS_ARCH");
+    println!("cargo:rustc-cfg=feature=\"arch_{}\"", arch);
+
+    println!("cargo:rerun-if-changed=src/arch/{}/asm", arch);
+
+    // specify the linker.ld script
+    println!("cargo:rustc-link-arg=-Tsrc/arch/{arch}/asm/linker.ld");
+
+    // output relocation info
+    println!("cargo:rustc-link-arg=--emit-relocs");
+
+    // don't page align sections
+    println!("cargo:rustc-link-arg=-n");
+}

blood/src/arch/mod.rs

@@ -0,0 +1,2 @@
+#[cfg(feature = "arch_riscv32")]
+mod riscv32;

blood/src/arch/riscv32/asm/linker.ld

@@ -0,0 +1,34 @@
+OUTPUT_FORMAT( "elf32-littleriscv" )
+OUTPUT_ARCH( "riscv" )
+
+ENTRY( _start )
+
+MEMORY
+{
+    program (wxa) : ORIGIN = 0x0, LENGTH = 20480
+}
+
+PHDRS
+{
+    prg PT_LOAD ;
+}
+
+SECTIONS {
+    .text : {
+        . = ALIGN(512);
+        *(.text .text.*)
+    } >program AT>program :prg
+
+    .rodata : {
+        *(.rodata .rodata.*)
+    } >program AT>program :prg
+
+    .data : {
+        *(.sdata .sdata.*) *(.data .data.*)
+    } >program AT>program :prg
+
+    .bss : {
+        *(.sbss .sbss.*)
+        *(.bss .bss.*)
+    } >program AT>program :prg
+}

blood/src/arch/riscv32/mod.rs

@@ -0,0 +1,10 @@
+use crate::main;
+
+#[unsafe(no_mangle)]
+extern "C" fn _start() -> isize {
+    unsafe {
+        main();
+    }
+
+    0
+}

blood/src/main.rs

@@ -0,0 +1,83 @@
+#![no_std]
+#![no_main]
+
+use liblbos::fs::{DirectoryReader, FileSystem};
+
+#[panic_handler]
+fn panic(info: &core::panic::PanicInfo) -> ! {
+    liblbos::syscalls::write_terminal(b"abort\n");
+    loop {}
+}
+mod arch;
+
+#[unsafe(no_mangle)]
+extern "C" fn main() {
+    loop {
+        const TURNTBL: &str = "TURNTBL.DDI";
+        let mut fs = FileSystem::empty();
+        if liblbos::ktask::ktask_fsopen(&mut fs) != 0 {
+            liblbos::syscalls::write_terminal(b"failed to open fs\n");
+            continue;
+        }
+        let mut dir = DirectoryReader::empty();
+        if liblbos::ktask::ktask_fsopendir(&fs, &mut dir, b"/") != 0 {
+            liblbos::syscalls::write_terminal(b"failed to open dir\n");
+            continue;
+        }
+        let mut record = liblbos::fs::Record {
+            name: [0; 12],
+            record_type: 0,
+            target: 0,
+            total_size_bytes: 0,
+        };
+        fn namecmp(record: &liblbos::fs::Record, name: &[u8]) -> bool {
+            for (i, &x) in record.name.iter().enumerate() {
+                if x == 0 {
+                    return &record.name[..i] == name;
+                }
+            }
+            false
+        }
+        while !namecmp(&record, TURNTBL.as_bytes()) {
+            if liblbos::ktask::ktask_fsreaddir(&fs, &mut dir, &mut record) != 0 {
+                liblbos::syscalls::write_terminal(b"failed to read dir\n");
+                continue;
+            }
+            if record.record_type == 0 {
+                liblbos::syscalls::write_terminal(b"unexpected eod\n");
+            }
+        }
+        // found turntable, load it
+        let mut reader = liblbos::fs::FileReader::empty();
+        if liblbos::ktask::ktask_fsopenfile(&fs, &record, &mut reader) != 0 {
+            liblbos::syscalls::write_terminal(b"failed to open file\n");
+            continue;
+        }
+        let size = record.total_size_bytes as usize;
+        let buf = liblbos::syscalls::alloc_blocks(size.div_ceil(512));
+        if liblbos::ktask::ktask_fsreadfile(&fs, &mut reader, unsafe { core::slice::from_raw_parts_mut(buf as *mut _, size) }) != 0 {
+            liblbos::syscalls::write_terminal(b"failed to read file\n");
+        }
+
+        let mut task_setup = liblbos::TaskSetup {
+            epc: 0,
+            stack_block_count: 2,
+            ddi_first_addr: 0,
+            ddi_size: 0,
+            environment: 0,
+            wait_for_task_exit: false,
+        };
+
+        if liblbos::ktask::ktask_loadddifile(buf, size, &mut task_setup as *mut _ as usize) != 0 {
+            liblbos::syscalls::write_terminal(b"failed to load ddi\n");
+            liblbos::syscalls::free_blocks(buf, size.div_ceil(512));
+            continue;
+        }
+
+        liblbos::syscalls::free_blocks(buf, size.div_ceil(512));
+
+        liblbos::syscalls::create_task(task_setup);
+
+        liblbos::syscalls::wait_until_alone();
+    }
+}

copy_to_fs.sh

@@ -8,6 +8,7 @@ mkdir -p mount
 mount "${storage_device}" mount
 
 echo "COPYING..."
+cp -v blood/target/riscv32imac-unknown-none-elf/release/BLOOD.DDI mount
 cp -v turntable/target/riscv32imac-unknown-none-elf/release/TURNTBL.DDI mount
 cp -v example/target/riscv32imac-unknown-none-elf/release/EXAMPLE.DDI mount
 

liblbos/src/lib.rs

@@ -9,6 +9,8 @@ mod arch;
 #[repr(C)]
 pub struct TaskSetup {
     pub epc: usize,
+    pub stack_block_count: usize,
+    /// MUST BE NON-ZERO
     pub ddi_first_addr: usize,
     pub ddi_size: usize,
     pub environment: usize,

liblbos/src/syscalls.rs

@@ -81,6 +81,8 @@ pub enum SysCall {
     /// if there is no device providing a gpu, this will not do anything
     FlushFramebufferRect = 18,
 
+    /// doens't return until all other tasks besides the current task and the ktask have exited
+    WaitUntilAlone = 333,
     /// initializes kernel, ONLY CALL ONCE! IN FACT, YOU PROBABLY NEVER NEED TO CALL THIS
     InitKernel = 666
 }
@@ -110,6 +112,7 @@ pub fn usize2sc(u: usize) -> SysCall {
         16 => SysCall::EnableFramebufferConsole,
         17 => SysCall::FramebufferPointer,
         18 => SysCall::FlushFramebufferRect,
+        333 => SysCall::WaitUntilAlone,
         666 => SysCall::InitKernel,
         _ => SysCall::NoAction,
     }
@@ -199,6 +202,10 @@ pub fn flush_framebuffer_rect(x: usize, y: usize, w: usize, h: usize) {
     syscall(SysCall::FlushFramebufferRect, x, y, w, h, 0, 0);
 }
 
+pub fn wait_until_alone() {
+    syscall(SysCall::WaitUntilAlone, 0, 0, 0, 0, 0, 0);
+}
+
 pub fn init_kernel() {
     syscall(SysCall::InitKernel, 0, 0, 0, 0, 0, 0);
 }

src/arch/virt/mod.rs

@@ -81,6 +81,7 @@ extern "C" fn _virt_init() -> ! {
 
     create_task(TaskSetup {
         epc: ktask as usize,
+        stack_block_count: 2,
         ddi_first_addr: 0,
         ddi_size: 0,
         environment: 0,

src/main.rs

@@ -32,7 +32,7 @@ pub extern "C" fn ktask() -> ! {
     syscalls::init_kernel();
     print(b"kernel ready!\n");
 
-    // load TURNTBL.DDI
+    // load BLOOD.DDI
 
     {
         fn fserr() {
@@ -62,13 +62,13 @@ pub extern "C" fn ktask() -> ! {
             record_name == name
         }
 
-        while !namecmp(&record, b"TURNTBL.DDI") {
+        while !namecmp(&record, b"BLOOD.DDI") {
             if !fs::read_one_record(
                 unsafe { &*(&fs as *const _ as *const _) },
                 unsafe { &mut *(&mut dir as *mut _ as *mut _) },
                 unsafe { &mut *(&mut record as *mut _ as *mut _) }
             ) {
-                print(b"TURNTBL.DDI NOT FOUND ):");
+                print(b"BLOOD.DDI NOT FOUND ):");
                 print(b"\n");
                 rough_panic(['t', 't', 'b']);
             }
@@ -89,23 +89,28 @@ pub extern "C" fn ktask() -> ! {
             unsafe { &mut *(&mut reader as *mut _ as *mut _) },
             unsafe { core::slice::from_raw_parts_mut(buf as *mut _, size) }
         ) != 0 {
-            print(b"TURNTBL.DDI READ ERROR ):");
+            print(b"BLOOD.DDI READ ERROR ):");
             print(b"\n");
             rough_panic(['f', 'r', 'e']);
         }
 
         // load the ddi
         let file_contents = unsafe { core::slice::from_raw_parts(buf as *const _, size) };
+        let file_size = size;
         if let Ok((entrypoint, first_addr, size)) = ddi::load_ddi(&file_contents) {
+            // free the buffer
+            syscalls::free_blocks(buf, file_size.div_ceil(512));
+
             create_task(TaskSetup {
                 epc: entrypoint,
+                stack_block_count: 1,
                 ddi_first_addr: first_addr,
                 ddi_size: size,
                 environment: 0,
                 wait_for_task_exit: false,
             });
         } else {
-            print(b"TURNTBL.DDI INVALID DDI ):");
+            print(b"BLOOD.DDI INVALID DDI ):");
             print(b"\n");
             rough_panic(['t', 't', 'b']);
         }

src/memory.rs

@@ -26,7 +26,7 @@ impl MemoryManager {
                 uart.putstr("heap_start: ");
                 uart.put_bytes(&u32_hex(_heap_start as u32));
                 uart.putstr("totalmem: ");
-                uart.put_bytes(&u32_hex(_heap_size as u32));
+                uart.put_bytes(&u32_hex(_heap_size as u32 / BLOCK_SIZE as u32));
                 uart.putstr("\n");
             }
         }

src/trafficcontrol.rs

@@ -12,10 +12,9 @@ pub enum TaskWait {
     HardBlockDevOperation = 1 << 0,
     WaitForNotification = 1 << 1,
     WaitForTaskExit = 1 << 2,
+    WaitUntilAlone = 1 << 7,
 }
 
-pub const STACK_SIZE_IN_BLOCKS: usize = 8;
-
 pub const MAX_TASKS: usize = 8;
 
 pub static TC: Spinlock<TrafficControl> = Spinlock::new(TrafficControl::empty());
@@ -69,13 +68,15 @@ pub fn handle_syscall(
             SysCall::CreateTask => {
                 let add = a1 as *mut TaskSetup;
 
+                let stack_size_in_blocks = unsafe { (*add).stack_block_count };
+
                 tc.init_mem_if_not();
                 let sp = unsafe {
                     tc.memory_manager
                         .as_mut()
                         .unwrap_unchecked()
-                        .alloc_n_blocks(STACK_SIZE_IN_BLOCKS)
+                        .alloc_n_blocks(stack_size_in_blocks)
-                } + (BLOCK_SIZE * STACK_SIZE_IN_BLOCKS);
+                } + (BLOCK_SIZE * stack_size_in_blocks);
 
                 #[cfg(feature = "arch_virt")]
                 let t = Some(Task {
@@ -83,6 +84,7 @@ pub fn handle_syscall(
                     environment: unsafe { (*add).environment },
                     want_exit: false,
                     sp,
+                    stack_size_in_blocks,
                     wait: 0,
                     incoming_notifications: [const { None }; MAX_TASKS],
                     ackwait: [0; MAX_TASKS],
@@ -90,7 +92,7 @@ pub fn handle_syscall(
                     ddi_mem_start: unsafe {
                         (*add).ddi_first_addr
                     },
-                    ddi_mem_blocks_count: unsafe { (*add).ddi_size / BLOCK_SIZE },
+                    ddi_mem_blocks_count: unsafe { (*add).ddi_size.div_ceil(BLOCK_SIZE) },
                     trap_frame: arch::virt::tasks::setup_task(sp),
                 });
 
@@ -371,6 +373,13 @@ pub fn handle_syscall(
                 crate::dev::framebuffer_push(&mut tc, x, y, w, h);
                 0
             }
+            SysCall::WaitUntilAlone => {
+                let ci = tc.current;
+                let mut task = tc.tasks[ci].as_mut().unwrap();
+                task.wait |= TaskWait::WaitForTaskExit as u32;
+                suspend = true;
+                0
+            }
         },
         suspend,
     )
@@ -380,7 +389,12 @@ pub fn context_switch<'a>(tc: &'a mut TrafficControl, current: Task) -> Option<&
     let ci = tc.current;
     tc.tasks[ci] = Some(current);
 
+    let mut remaining_tasks = 0;
+
     for i in 0..tc.tasks.len() {
+        if tc.tasks[i].is_some() {
+            remaining_tasks += 1;
+        }
         let want_exit = tc.tasks[i]
             .as_ref()
             .map(|task| task.want_exit)
@@ -390,12 +404,13 @@ pub fn context_switch<'a>(tc: &'a mut TrafficControl, current: Task) -> Option<&
             let sp = tc.tasks[i].as_ref().map(|v| v.sp).unwrap_or(0);
             let ddi_start_block = tc.tasks[i].as_ref().map(|v| v.ddi_mem_start).unwrap_or(0);
             let ddi_blocks_count = tc.tasks[i].as_ref().map(|v| v.ddi_mem_blocks_count).unwrap_or(0);
+            let stack_size_in_blocks = tc.tasks[i].as_ref().map(|v| v.stack_size_in_blocks).unwrap_or(0);
             if sp != 0 {
                 unsafe {
                     tc.memory_manager
                         .as_mut()
                         .unwrap_unchecked()
-                        .free_n_blocks(sp - (BLOCK_SIZE * STACK_SIZE_IN_BLOCKS), STACK_SIZE_IN_BLOCKS)
+                        .free_n_blocks(sp - (BLOCK_SIZE * stack_size_in_blocks), stack_size_in_blocks)
                 };
                 unsafe {
                     tc.memory_manager.as_mut().unwrap_unchecked()
@@ -414,6 +429,17 @@ pub fn context_switch<'a>(tc: &'a mut TrafficControl, current: Task) -> Option<&
         }
     }
 
+    // if remaining_tasks <= 2, then we need to wake up WaitUntilAlone tasks
+    if remaining_tasks <= 2 {
+        for task in &mut tc.tasks {
+            if let Some(task) = task {
+                if task.wait & TaskWait::WaitForTaskExit as u32 != 0 {
+                    task.wait &= !(TaskWait::WaitForTaskExit as u32);
+                }
+            }
+        }
+    }
+
     let mut next_task = tc.current + 1;
     if next_task >= MAX_TASKS {
         next_task = 0;
@@ -421,6 +447,19 @@ pub fn context_switch<'a>(tc: &'a mut TrafficControl, current: Task) -> Option<&
 
     for _ in 0..(MAX_TASKS + 1) {
         if let Some(task) = tc.tasks[next_task].as_ref() {
+            // check stack pointer and if it's oob
+            #[cfg(feature = "arch_virt")]
+            {
+                if task.sp != 0 {
+                    if task.trap_frame.regs[2] < task.sp - (task.stack_size_in_blocks * BLOCK_SIZE) {
+                        let uart = serial_port();
+                        if let Some(uart) = uart {
+                            uart.putstr("stack overflow\n");
+                        }
+                        rough_panic([';', '-', ';'])
+                    }
+                }
+            }
             if task.wait == 0 && {
                 let mut waiting = false;
                 for v in &task.ackwait {
@@ -464,6 +503,7 @@ pub struct Task {
     pub want_exit: bool,
     /// THE ORIGINAL STACK POINTER THAT THE TASK STARTED WITH
     pub sp: usize,
+    pub stack_size_in_blocks: usize,
     pub wait: u32,
     pub incoming_notifications: [Option<usize>; MAX_TASKS],
     pub ackwait: [u8; MAX_TASKS], // 3 = they have not yet received the notification, 1 = they have received the notification, 0 = we know they received the notification, or don't care

turntable/src/main.rs

@@ -187,13 +187,16 @@ fn attempt_run_file(env: &Environment<'_>, name: &str) {
         current_directory_path: CURRENT_DIR_PATH.load(Ordering::Relaxed) as usize,
         current_directory_path_len: CURRENT_DIR_PATH_LEN.load(Ordering::Relaxed),
     };
+    // fixme: turntable task needs to exit, but it owns the environment memory.
+    // fixme: we need to somehow pass the environment to the task, and have it free the memory
 
     let mut task_setup = liblbos::TaskSetup {
         epc: 0,
+        stack_block_count: 8,
         ddi_first_addr: 0,
         ddi_size: 0,
-        environment: &e as *const _ as usize,
+        environment: 0,
-        wait_for_task_exit: true,
+        wait_for_task_exit: false,
     };
 
     if liblbos::ktask::ktask_loadddifile(buf, size, &mut task_setup as *mut _ as usize) != 0 {
@@ -206,11 +209,11 @@ fn attempt_run_file(env: &Environment<'_>, name: &str) {
 
     liblbos::syscalls::create_task(task_setup);
 
-    // yeah we're extending its lifetime
+    if CURRENT_DIR_PATH.load(Ordering::Relaxed) as usize != 0 {
-    #[allow(clippy::drop_non_drop)]
+        // free
-    drop(e);
+        liblbos::syscalls::free_blocks(CURRENT_DIR_PATH.load(Ordering::Relaxed) as usize, CURRENT_DIR_PATH_LEN.load(Ordering::Relaxed).div_ceil(512));
-
+    }
-    println("\ntask exited\n");
+    liblbos::syscalls::exit();
 }
 
 fn execute(cmd: &str, environment: &mut Environment<'_>) {
@@ -233,6 +236,10 @@ fn execute(cmd: &str, environment: &mut Environment<'_>) {
                 if NO_EXIT.load(Ordering::Relaxed) {
                     println("cannot exit as task 1");
                 } else {
+                    if CURRENT_DIR_PATH.load(Ordering::Relaxed) as usize != 0 {
+                        // free
+                        liblbos::syscalls::free_blocks(CURRENT_DIR_PATH.load(Ordering::Relaxed) as usize, CURRENT_DIR_PATH_LEN.load(Ordering::Relaxed).div_ceil(512));
+                    }
                     liblbos::syscalls::exit();
                 }
             }
@@ -260,8 +267,7 @@ fn hex(mut n: u8) -> [u8; 2] {
 mod arch;
 mod terminal;
 
-#[unsafe(no_mangle)]
+fn main_wrapper() {
-extern "C" fn main() {
     let tid = liblbos::syscalls::current_task();
     NO_EXIT.store(tid == 1, Ordering::Relaxed);
 
@@ -341,3 +347,12 @@ extern "C" fn main() {
         }
     }
 }
+
+#[unsafe(no_mangle)]
+extern "C" fn main() {
+    main_wrapper();
+    if CURRENT_DIR_PATH.load(Ordering::Relaxed) as usize != 0 {
+        // free
+        liblbos::syscalls::free_blocks(CURRENT_DIR_PATH.load(Ordering::Relaxed) as usize, CURRENT_DIR_PATH_LEN.load(Ordering::Relaxed).div_ceil(512));
+    }
+}