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annotate src/proc.c @ 53:23abbeea4d5f

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llalallalala
author John Tsiombikas <nuclear@member.fsf.org>
date Mon, 08 Aug 2011 09:53:10 +0300
parents fa65b4f45366
children 4eaecb14fe31
rev   line source
nuclear@52 1 #include <stdio.h>
nuclear@47 2 #include <string.h>
nuclear@52 3 #include <assert.h>
nuclear@42 4 #include "proc.h"
nuclear@42 5 #include "tss.h"
nuclear@45 6 #include "vm.h"
nuclear@47 7 #include "segm.h"
nuclear@47 8 #include "intr.h"
nuclear@47 9 #include "panic.h"
nuclear@51 10 #include "syscall.h"
nuclear@51 11 #include "sched.h"
nuclear@47 12
nuclear@52 13 #define FLAGS_INTR_BIT 9
nuclear@47 14
nuclear@47 15 /* defined in test_proc.S */
nuclear@47 16 void test_proc(void);
nuclear@47 17 void test_proc_end(void);
nuclear@42 18
nuclear@42 19 static struct process proc[MAX_PROC];
nuclear@42 20 static int cur_pid;
nuclear@42 21
nuclear@42 22 void init_proc(void)
nuclear@42 23 {
nuclear@47 24 int proc_size_pg, img_start_pg, stack_pg;
nuclear@45 25 void *img_start;
nuclear@51 26 cur_pid = 0;
nuclear@51 27
nuclear@51 28 init_syscall();
nuclear@42 29
nuclear@42 30 /* prepare the first process */
nuclear@51 31 proc[1].id = 1;
nuclear@51 32 proc[1].parent = 0;
nuclear@42 33
nuclear@42 34 /* allocate a chunk of memory for the process image
nuclear@42 35 * and copy the code of test_proc there.
nuclear@42 36 * (should be mapped at a fixed address)
nuclear@42 37 */
nuclear@51 38 proc_size_pg = (test_proc_end - test_proc) / PGSIZE + 1;
nuclear@45 39 if((img_start_pg = pgalloc(proc_size_pg, MEM_USER)) == -1) {
nuclear@45 40 panic("failed to allocate space for the init process image\n");
nuclear@45 41 }
nuclear@45 42 img_start = (void*)PAGE_TO_ADDR(img_start_pg);
nuclear@51 43 memcpy(img_start, test_proc, proc_size_pg * PGSIZE);
nuclear@45 44
nuclear@52 45 printf("copied init process at: %x\n", (unsigned int)img_start);
nuclear@52 46
nuclear@47 47 /* instruction pointer at the beginning of the process image */
nuclear@51 48 proc[1].ctx.instr_ptr = (uint32_t)img_start;
nuclear@47 49
nuclear@47 50 /* allocate the first page of the process stack */
nuclear@47 51 stack_pg = ADDR_TO_PAGE(KMEM_START) - 1;
nuclear@47 52 if(pgalloc_vrange(stack_pg, 1) == -1) {
nuclear@47 53 panic("failed to allocate user stack page\n");
nuclear@47 54 }
nuclear@51 55 proc[1].ctx.stack_ptr = PAGE_TO_ADDR(stack_pg) + PGSIZE;
nuclear@53 56 proc[1].stack_start_pg = stack_pg;
nuclear@52 57
nuclear@45 58 /* create the virtual address space for this process */
nuclear@53 59 /*proc[1].ctx.pgtbl_paddr = clone_vm();*/
nuclear@45 60
nuclear@47 61 /* we don't need the image and the stack in this address space */
nuclear@53 62 /*unmap_page_range(img_start_pg, proc_size_pg);
nuclear@51 63 pgfree(img_start_pg, proc_size_pg);
nuclear@45 64
nuclear@47 65 unmap_page(stack_pg);
nuclear@53 66 pgfree(stack_pg, 1);*/
nuclear@42 67
nuclear@51 68 /* add it to the scheduler queues */
nuclear@53 69 add_proc(1, STATE_RUNNABLE);
nuclear@42 70
nuclear@51 71 /* switch to the initial process, this never returns */
nuclear@51 72 context_switch(1);
nuclear@42 73 }
nuclear@42 74
nuclear@47 75
nuclear@47 76 void context_switch(int pid)
nuclear@42 77 {
nuclear@52 78 struct context *ctx;
nuclear@47 79 struct intr_frame ifrm;
nuclear@52 80 struct intr_frame *cur_frame = get_intr_frame();
nuclear@47 81
nuclear@52 82 assert(0);
nuclear@49 83
nuclear@52 84 if(cur_pid == pid) {
nuclear@52 85 assert(cur_frame);
nuclear@52 86 intr_ret(*cur_frame);
nuclear@52 87 }
nuclear@52 88
nuclear@52 89 ctx = &proc[pid].ctx;
nuclear@47 90 cur_pid = pid;
nuclear@47 91
nuclear@47 92 ifrm.inum = ifrm.err = 0;
nuclear@47 93
nuclear@47 94 ifrm.regs = ctx->regs;
nuclear@52 95 ifrm.eflags = ctx->flags | (1 << FLAGS_INTR_BIT);
nuclear@47 96
nuclear@47 97 ifrm.eip = ctx->instr_ptr;
nuclear@49 98 ifrm.cs = selector(SEGM_KCODE, 0); /* XXX change this when we setup the TSS */
nuclear@52 99 /*ifrm.regs.esp = ctx->stack_ptr;*/ /* ... until then... */
nuclear@52 100 ifrm.esp = ctx->stack_ptr; /* this will only be used when we switch to userspace */
nuclear@52 101 ifrm.ss = selector(SEGM_KDATA, 0);
nuclear@47 102
nuclear@47 103 /* switch to the vm of the process */
nuclear@47 104 set_pgdir_addr(ctx->pgtbl_paddr);
nuclear@47 105 intr_ret(ifrm);
nuclear@47 106 }
nuclear@51 107
nuclear@51 108 int get_current_pid(void)
nuclear@51 109 {
nuclear@51 110 return cur_pid;
nuclear@51 111 }
nuclear@51 112
nuclear@51 113 struct process *get_current_proc(void)
nuclear@51 114 {
nuclear@51 115 return cur_pid ? &proc[cur_pid] : 0;
nuclear@51 116 }
nuclear@51 117
nuclear@51 118 struct process *get_process(int pid)
nuclear@51 119 {
nuclear@51 120 return &proc[pid];
nuclear@51 121 }