Struct Process 

pub struct Process {
    pub file_struct: FileStruct,
}

A process state of project 1, which contains file state.

Fields

file_struct: FileStruct

Trait Implementations

impl Default for Process

fn default() -> Process

Returns the “default value” for a type.

impl Task for Process

fn syscall(&mut self, regs: &mut Registers)

Handles a system call request from a user program.

This function is the entry point for system call handling. It retrieves the system call ABI from the provided Registers structure, which includes the system call number and its arguments. Based on the system call number (sysno), it looks up the appropriate handler function in a predefined list. If a handler is found, it is invoked with the ABI, otherwise, an error (KernelError::NoSuchSyscall) is returned.

After the handler function processes the system call, the return value (either a success or error) is set back into the CPU registers via the set_return_value method. The return value is stored in the %rax register as per the x86-64 system call convention.

Parameters

• regs: A mutable reference to the Registers struct, which contains the current state of the CPU registers. This structure will be used to retrieve the system call number and its arguments, and also to set the return value.

Functionality

The function processes the system call as follows:

1. Extracts the system call number and arguments using the SyscallAbi::from_registers.
2. Looks up the corresponding handler function from a predefined list of system calls. The handler function is selected based on the system call number (sysno).
3. If a handler is found, it is executed with the ABI as an argument. If no handler is found, the function returns a KernelError::NoSuchSyscall error.

The result of the system call handler (either success or error) is then returned via the SyscallAbi::set_return_value method, which modifies the CPU registers accordingly.

fn page_fault(&mut self, ec: PFErrorCode, cr2: Va)

Handles a page fault that occurs when accessing an unmapped memory page.

fn access_ok(&self, addr: Range<Va>, is_write: bool) -> bool

Validates a given memory address range before use.

fn with_page_table_pa(&self, _f: &fn(Pa))

Run a closure with physical address of the page table.