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#include <mutex.h>
#include <hashtbl.h>
#include <process.h>
typedef struct user_region {
void* addr;
size_t size;
int mode;
fs_handle_t *file; // null if not mmaped-file
size_t file_offset;
struct user_region *next;
} user_region_t;
typedef struct process {
pagedir_t *pd;
user_region_t *regions;
hashtbl_t *filesystems;
thread_t *thread;
int pid;
struct process *parent;
} process_t;
static int next_pid = 1;
static void proc_kmem_violation(registers_t *regs);
static void proc_user_pf(void* proc, registers_t *regs, void* addr);
process_t *current_process() {
if (current_thread) return current_thread->proc;
return 0;
}
// ============================== //
// CREATING AND RUNNING PROCESSES //
// ============================== //
process_t *new_process(process_t *parent) {
process_t *proc = (proces_t*)malloc(sizeof(process_t));
if (proc == 0) return 0;
proc->filesystems = create_hashtbl(str_key_eq_fun, str_hash_fun, free, 0);
if (proc->filesystems == 0) {
free(proc);
return 0;
}
proc->pd = pagedir_create(proc_user_pf, proc);
if (proc->pd == 0) {
delete_hashtbl(proc->filesystems, 0);
free(proc);
return 0;
}
proc->regions = 0;
proc->thread = 0;
proc->pid = (next_pid++);
proc->parent = parent;
return proc;
}
static void run_user_code(void* entry) {
process_t *proc = current_thread->proc;
ASSERT(proc != 0);
switch_pagedir(proc->pd);
void* esp = (void*)USERSTACK_ADDR + USERSTACK_SIZE;
asm volatile("
cli;
mov $0x23, %%ax;
mov %%ax, %%ds;
mov %%ax, %%es;
mov %%ax, %%fs;
mov %%ax, %%gs;
pushl $0x23;
pushl %%ebx;
pushf;
pop %%eax;
or $0x200, %%eax;
pushl %%eax;
pushl $0x1B;
pushl %%ecx;
iret
"::"b"(esp),"c"(entry));
}
bool start_process(process_t *p, void* entry) {
bool stack_ok = mmap(p, (void*)USERSTACK_ADDR, USERSTACK_SIZE, MM_READ | MM_WRITE);
if (!stack_ok) return false;
thread_t *th = new_thread(run_user_code, entry);
if (th == 0) {
munmap(p, (void*)USERSTACK_ADDR);
return false;
}
th->proc = p;
th->kmem_violation_handler = proc_kmem_violation;
resume_thread(th, false);
return true;
}
// ================================== //
// MANAGING FILESYSTEMS FOR PROCESSES //
// ================================== //
bool proc_add_fs(process_t *p, fs_t *fs, const char* name) {
char *n = strdup(name);
if (n == 0) return false;
bool add_ok = hashtbl_add(p->filesystems, n, fs);
if (!add_ok) {
free(n);
return false;
}
return true;
}
fs_t *proc_find_fs(process_t *p, const char* name) {
return hashtbl_find(p->filesystems, name);
}
// ============================= //
// USER MEMORY REGION MANAGEMENT //
// ============================= //
bool mmap(process_t *proc, void* addr, size_t size, int mode) {
//TODO
return false;
}
bool mmap_file(process_t *proc, fs_handle_t *h, size_t offset, void* addr, size_t size, int mode) {
//TODO
return false;
}
bool mchmap(process_t *proc, void* addr, int mode) {
//TODO
return false;
}
bool munmap(process_t *proc, void* addr) {
//TODO
return false;
}
// =============================== //
// USER MEMORY PAGE FAULT HANDLERS //
// =============================== //
static void proc_kmem_violation(registers_t *regs) {
//TODO
dbg_printf("Kernel memory violation in user process : exiting.\n");
exit();
}
static void proc_user_pf(void* proc, registers_t *regs, void* addr) {
//TODO
PANIC("TODO");
}
/* vim: set ts=4 sw=4 tw=0 noet :*/
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