[syscall] Split syscalls into multiple files according to the syscall…

… categories

Cargo.toml

@@ -24,3 +24,6 @@ axmm = { git = "https://github.com/arceos-org/arceos.git" }
 axtask = { git = "https://github.com/arceos-org/arceos.git" }
 axsync = { git = "https://github.com/arceos-org/arceos.git" }
 axruntime = { git = "https://github.com/arceos-org/arceos.git", features = ["multitask"] }
+
+[target.'cfg(target_arch = "x86_64")'.dependencies]
+x86 = "0.52"

src/main.rs

@@ -9,7 +9,7 @@ extern crate axstd;
 
 mod loader;
 mod mm;
-mod syscall;
+mod syscall_imp;
 mod task;
 use alloc::sync::Arc;
 

src/mm.rs

@@ -2,9 +2,12 @@ use alloc::string::ToString;
 use axerrno::AxResult;
 use memory_addr::{MemoryAddr, PageIter4K, VirtAddr, PAGE_SIZE_4K};
 
-use axhal::mem::phys_to_virt;
-use axhal::paging::MappingFlags;
-use axhal::trap::{register_trap_handler, PAGE_FAULT};
+use axhal::{
+    mem::phys_to_virt,
+    paging::MappingFlags,
+    trap::{register_trap_handler, PAGE_FAULT},
+};
+
 use axmm::AddrSpace;
 use axtask::TaskExtRef;
 
@@ -71,33 +74,37 @@ pub fn load_user_app(app_name: &str) -> AxResult<(VirtAddr, VirtAddr, AddrSpace)
         // TDOO: flush the I-cache
     }
 
-    let ustack_base = uspace.end();
+    // The user stack is divided into two parts:
+    // `ustack_bottom` -> `ustack top`: It is the stack space that users actually read and write.
+    // `ustack_top` -> `ustack end`: It is the space that contains the arguments, environment variables and auxv passed to the app.
+    //  When the app starts running, the stack pointer points to `ustack_top`.
+    let ustack_end = uspace.end();
     let ustack_size = crate::USER_STACK_SIZE;
-    let ustack_top = ustack_base - ustack_size;
+    let ustack_bottom = ustack_end - ustack_size;
     debug!(
         "Mapping user stack: {:#x?} -> {:#x?}",
-        ustack_top, ustack_base
+        ustack_bottom, ustack_end
     );
     // FIXME: Add more arguments and environment variables
-    let (stack_data, ustack_bottom) = elf_parser::get_app_stack_region(
+    let (stack_data, ustack_top) = elf_parser::get_app_stack_region(
         &[app_name.to_string()],
         &[],
         &elf_info.auxv,
-        ustack_top,
+        ustack_bottom,
         ustack_size,
     );
     uspace.map_alloc(
-        ustack_top,
+        ustack_bottom,
         ustack_size,
         MappingFlags::READ | MappingFlags::WRITE | MappingFlags::USER,
         true,
     )?;
     {
         // Copy the stack data to the user stack
-        let ustack_bottom_align = VirtAddr::from_usize(ustack_bottom).align_down_4k();
-        let stack_data_offset = ustack_bottom_align - ustack_top;
+        let ustack_top_align = VirtAddr::from_usize(ustack_top).align_down_4k();
+        let stack_data_offset = ustack_top_align - ustack_bottom;
         // Only copy data which contains args, envs and auxv.
-        for (idx, vaddr) in PageIter4K::new(ustack_bottom_align, ustack_base)
+        for (idx, vaddr) in PageIter4K::new(ustack_top_align, ustack_end)
             .expect("Failed to create page iterator")
             .enumerate()
         {
@@ -116,7 +123,7 @@ pub fn load_user_app(app_name: &str) -> AxResult<(VirtAddr, VirtAddr, AddrSpace)
         }
     }
 
-    Ok((elf_info.entry, VirtAddr::from(ustack_bottom), uspace))
+    Ok((elf_info.entry, VirtAddr::from(ustack_top), uspace))
 }
 
 #[register_trap_handler(PAGE_FAULT)]

src/syscall_imp/fs/ctl.rs

@@ -0,0 +1,18 @@
+use core::ffi::c_void;
+
+use crate::syscall_body;
+
+/// The ioctl() system call manipulates the underlying device parameters
+/// of special files.
+///
+/// # Arguments
+/// * `fd` - The file descriptor
+/// * `op` - The request code. It is of type unsigned long in glibc and BSD,
+/// and of type int in musl and other UNIX systems.
+/// * `argp` - The argument to the request. It is a pointer to a memory location
+pub(crate) fn sys_ioctl(_fd: i32, _op: usize, _argp: *mut c_void) -> i32 {
+    syscall_body!(sys_ioctl, {
+        warn!("Unimplemented syscall: SYS_IOCTL");
+        Ok(0)
+    })
+}

src/syscall_imp/fs/io.rs

@@ -0,0 +1,14 @@
+use core::ffi::c_void;
+
+use arceos_posix_api as api;
+
+pub(crate) fn sys_read(fd: i32, buf: *mut c_void, count: usize) -> isize {
+    api::sys_read(fd, buf, count)
+}
+pub(crate) fn sys_write(fd: i32, buf: *const c_void, count: usize) -> isize {
+    api::sys_write(fd, buf, count)
+}
+
+pub(crate) fn sys_writev(fd: i32, iov: *const api::ctypes::iovec, iocnt: i32) -> isize {
+    unsafe { api::sys_writev(fd, iov, iocnt) }
+}

src/syscall_imp/fs/mod.rs

@@ -0,0 +1,5 @@
+mod ctl;
+mod io;
+
+pub(crate) use ctl::*;
+pub(crate) use io::*;