vasilito/RedBear-OS
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Add mmap-min-addr and support unmapping parent PTs.

Browse Source
This commit is contained in:
4lDO2
2022-07-23 19:14:46 +02:00
parent 0720db2265
commit 5bbfdcda6b
9 changed files with 219 additions and 118 deletions
Download Patch File Download Diff File Expand all files Collapse all files
src/syscall/process.rs
+4 -48
View File
@@ -6,7 +6,7 @@ use core::mem;
use spin::{RwLock, RwLockWriteGuard};
use crate::context::{Context, ContextId, WaitpidKey};
use crate::context::{Context, ContextId, memory::AddrSpace, WaitpidKey};
use crate::Bootstrap;
use crate::context;
@@ -289,54 +289,10 @@ pub fn kill(pid: ContextId, sig: usize) -> Result<usize> {
pub fn mprotect(address: usize, size: usize, flags: MapFlags) -> Result<usize> {
// println!("mprotect {:#X}, {}, {:#X}", address, size, flags);
let end_address = address.checked_add(size).ok_or(Error::new(EFAULT))?;
if address % PAGE_SIZE != 0 || size % PAGE_SIZE != 0 { return Err(Error::new(EINVAL)); }
if address.saturating_add(size) > crate::USER_END_OFFSET { return Err(Error::new(EFAULT)); }
let address_space = Arc::clone(context::current()?.read().addr_space()?);
let mut address_space = address_space.write();
let mut flush_all = PageFlushAll::new();
let start_page = Page::containing_address(VirtualAddress::new(address));
let end_page = Page::containing_address(VirtualAddress::new(end_address));
for page in Page::range_exclusive(start_page, end_page) {
// Check if the page is actually mapped before trying to change the flags.
// FIXME can other processes change if a page is mapped beneath our feet?
let mut page_flags = if let Some((_, flags)) = address_space.table.utable.translate(page.start_address()) {
flags
} else {
flush_all.flush();
return Err(Error::new(EFAULT));
};
if !page_flags.has_present() {
flush_all.flush();
return Err(Error::new(EFAULT));
}
if flags.contains(PROT_EXEC) {
page_flags = page_flags.execute(true);
} else {
page_flags = page_flags.execute(false);
}
if flags.contains(PROT_WRITE) {
//TODO: Not allowing gain of write privileges
} else {
page_flags = page_flags.write(false);
}
if flags.contains(PROT_READ) {
//TODO: No flags for readable pages
} else {
//TODO: No flags for readable pages
}
let flush = unsafe { address_space.table.utable.remap(page.start_address(), page_flags).expect("failed to remap page in mprotect") };
flush_all.consume(flush);
}
flush_all.flush();
Ok(0)
AddrSpace::current()?.write().mprotect(Page::containing_address(VirtualAddress::new(address)), size / PAGE_SIZE, flags).map(|()| 0)
}
pub fn setpgid(pid: ContextId, pgid: ContextId) -> Result<usize> {