Add Vmmap to src/rawposix

[rennergade]

This is where were going to add the vmmap for now so once the tests are up you two can PR to here.

[Yaxuan-w]

That would be great if @pranav-bhatt @ruchjoshi-nyu can post current VMMAP progress (including difficulties) and implementation details here

[Yaxuan-w]

Task tracker for implementing VMMAP in RawPOSIX

Add current code into RawPOSIX

• Add current VMMAP implementation into RawPOSIX (each cage structure has vmmap) - @Yaxuan-w
• Add comments - @ruchjoshi-nyu

Integration

Address picked by host calling vmmap, then use this addr to call kernel mmap, a function before mmap in dispatcher to check and pick addr for vmmap

• mmap / shm / munmap / brk- @qianxichen233

All translation about address should be done in dispatcher stage. Including all functions related to pointers
— handle situations depends on flags

• add full syscall list - @ChinmayShringi
• pwrite/pread (any syscall w/ ptr) — a function to check if region is valid - @ruchjoshi-nyu
• fork - @qianxichen233
• exec - @ChinmayShringi
• exit - @ChinmayShringi
• consolidate constants - @ChinmayShringi

Test

• Add tests for vmmap

[ChinmayShringi]

Below is the syscall list that uses pointer and doesn't use.

// Uses pointers
getcwd_syscall       // getcwd_syscall(&self, buf: *mut u8, bufsize: u32) -> i32
read_syscall         // read_syscall(&self, virtual_fd: i32, readbuf: *mut u8, count: usize) -> i32
write_syscall        // write_syscall(&self, virtual_fd: i32, buf: *const u8, count: usize) -> i32
ioctl_syscall        // ioctl_syscall(&self, virtual_fd: i32, request: u64, ptrunion: *mut u8) -> i32
mmap_syscall         // mmap_syscall(&self, addr: *mut u8, len: usize, prot: i32, flags: i32, virtual_fd: i32, off: i64) -> i32
munmap_syscall       // munmap_syscall(&self, addr: *mut u8, len: usize) -> i32
getdents_syscall     // getdents_syscall(&self, virtual_fd: i32, buf: *mut u8, nbytes: u32) -> i32
send_syscall         // send_syscall(&self, virtual_fd: i32, buf: *const u8, buflen: usize, flags: i32) -> i32
sendto_syscall       // sendto_syscall(&self, virtual_fd: i32, buf: *const u8, buflen: usize, flags: i32, dest_addr: &GenSockaddr) -> i32
shmat_syscall        // shmat_syscall(&self, shmid: i32, shmaddr: *mut u8, shmflg: i32) -> i32
shmdt_syscall        // shmdt_syscall(&self, shmaddr: *mut u8) -> i32
pread_syscall        // pread_syscall(&self, virtual_fd: i32, buf: *mut u8, count: usize, offset: i64) -> i32
pwrite_syscall       // pwrite_syscall(&self, virtual_fd: i32, buf: *const u8, count: usize, offset: i64) -> i32
getifaddrs_syscall   // getifaddrs_syscall(&self, buf: *mut u8, count: usize) -> i32
writev_syscall       // writev_syscall(&self,virtual_fd: i32,iovec: *const interface::IovecStruct,iovcnt: i32,) -> i32
recv_syscall         // recv_syscall(&self, virtual_fd: i32, buf: *mut u8, buflen: usize, flags: i32) -> i32
recvfrom_syscall     // recvfrom_syscall(&self, virtual_fd: i32, buf: *mut u8, buflen: usize, flags: i32, addr: &mut Option<&mut GenSockaddr>) -> i32
getsockopt_syscall   // getsockopt_syscall(&self, virtual_fd: i32, level: i32, optname: i32, optval: *mut u8, optlen: *mut u32) -> i32
setsockopt_syscall   // setsockopt_syscall(&self, virtual_fd: i32, level: i32, optname: i32, optval: *const u8, optlen: u32) -> i32
gethostname_syscall  // gethostname_syscall(&self, name: *mut u8, len: isize) -> i32

[rennergade]

Below is the syscall list that uses pointer and doesn't use.

// Uses pointers
getcwd_syscall       // getcwd_syscall(&self, buf: *mut u8, bufsize: u32) -> i32
read_syscall         // read_syscall(&self, virtual_fd: i32, readbuf: *mut u8, count: usize) -> i32
write_syscall        // write_syscall(&self, virtual_fd: i32, buf: *const u8, count: usize) -> i32
ioctl_syscall        // ioctl_syscall(&self, virtual_fd: i32, request: u64, ptrunion: *mut u8) -> i32
mmap_syscall         // mmap_syscall(&self, addr: *mut u8, len: usize, prot: i32, flags: i32, virtual_fd: i32, off: i64) -> i32
munmap_syscall       // munmap_syscall(&self, addr: *mut u8, len: usize) -> i32
getdents_syscall     // getdents_syscall(&self, virtual_fd: i32, buf: *mut u8, nbytes: u32) -> i32
send_syscall         // send_syscall(&self, virtual_fd: i32, buf: *const u8, buflen: usize, flags: i32) -> i32
sendto_syscall       // sendto_syscall(&self, virtual_fd: i32, buf: *const u8, buflen: usize, flags: i32, dest_addr: &GenSockaddr) -> i32
shmat_syscall        // shmat_syscall(&self, shmid: i32, shmaddr: *mut u8, shmflg: i32) -> i32
shmdt_syscall        // shmdt_syscall(&self, shmaddr: *mut u8) -> i32
pread_syscall        // pread_syscall(&self, virtual_fd: i32, buf: *mut u8, count: usize, offset: i64) -> i32
pwrite_syscall       // pwrite_syscall(&self, virtual_fd: i32, buf: *const u8, count: usize, offset: i64) -> i32
getifaddrs_syscall   // getifaddrs_syscall(&self, buf: *mut u8, count: usize) -> i32
writev_syscall       // writev_syscall(&self,virtual_fd: i32,iovec: *const interface::IovecStruct,iovcnt: i32,) -> i32
recv_syscall         // recv_syscall(&self, virtual_fd: i32, buf: *mut u8, buflen: usize, flags: i32) -> i32
recvfrom_syscall     // recvfrom_syscall(&self, virtual_fd: i32, buf: *mut u8, buflen: usize, flags: i32, addr: &mut Option<&mut GenSockaddr>) -> i32
getsockopt_syscall   // getsockopt_syscall(&self, virtual_fd: i32, level: i32, optname: i32, optval: *mut u8, optlen: *mut u32) -> i32
setsockopt_syscall   // setsockopt_syscall(&self, virtual_fd: i32, level: i32, optname: i32, optval: *const u8, optlen: u32) -> i32
gethostname_syscall  // gethostname_syscall(&self, name: *mut u8, len: isize) -> i32

I think theres a few of these that should use pointers but may not be as evident? Like I believe things like select and poll should use pointers but not sure what the interface is now. Maybe @Yaxuan-w can chime in.

[Yaxuan-w]

I think theres a few of these that should use pointers but may not be as evident? Like I believe things like select and poll should use pointers but not sure what the interface is now. Maybe @Yaxuan-w can chime in.

The dispatcher.rs being compared by Chinmay is the one after merging the WASM API PR. In that PR, some syscalls (e.g., select, epoll_ctl, epoll_wait) were not added to the dispatcher. I have already opened an issue for this and assigned Robin to address the missing syscalls.