# HG changeset patch
# User John Tsiombikas <nuclear@member.fsf.org>
# Date 1311582542 -10800
# Node ID 5f6c5751ae0515f78cf9254072411bc8aa1d6a02
# Parent  e6de3c6015cb26d28900e0235e0baf8c5325bacd
- implemented clone_vmem

diff -r e6de3c6015cb -r 5f6c5751ae05 src/asmops.h
--- a/src/asmops.h	Sun Jul 24 18:29:24 2011 +0300
+++ b/src/asmops.h	Mon Jul 25 11:29:02 2011 +0300
@@ -1,6 +1,8 @@
 #ifndef ASMOPS_H_
 #define ASMOPS_H_
 
+#include <inttypes.h>
+
 /* general purpose registers as they are pushed by pusha */
 struct registers {
 	uint32_t edi, esi, ebp, esp;
diff -r e6de3c6015cb -r 5f6c5751ae05 src/main.c
--- a/src/main.c	Sun Jul 24 18:29:24 2011 +0300
+++ b/src/main.c	Mon Jul 25 11:29:02 2011 +0300
@@ -10,35 +10,6 @@
 #include "mem.h"
 #include "vm.h"
 
-static void do_nothing();
-
-/* special keys */
-enum {
-	LALT, RALT,
-	LCTRL, RCTRL,
-	LSHIFT, RSHIFT,
-	F1, F2, F3, F4, F5, F6, F7, F8, F9, F10, F11, F12,
-	CAPSLK, NUMLK, SCRLK, SYSRQ,
-	ESC		= 27,
-	INSERT, DEL, HOME, END, PGUP, PGDN, LEFT, RIGHT, UP, DOWN,
-	NUM_DOT, NUM_ENTER, NUM_PLUS, NUM_MINUS, NUM_MUL, NUM_DIV,
-	NUM_0, NUM_1, NUM_2, NUM_3, NUM_4, NUM_5, NUM_6, NUM_7, NUM_8, NUM_9,
-	BACKSP	= 127
-};
-
-/* table with rough translations from set 1 scancodes to ASCII-ish */
-static int keycodes[] = {
-	0, ESC, '1', '2', '3', '4', '5', '6', '7', '8', '9', '0', '-', '=', '\b',		/* 0 - e */
-	'\t', 'q', 'w', 'e', 'r', 't', 'y', 'u', 'i', 'o', 'p', '[', ']', '\n',			/* f - 1c */
-	LCTRL, 'a', 's', 'd', 'f', 'g', 'h', 'j', 'k', 'l', ';', '\'', '`',				/* 1d - 29 */
-	LSHIFT, '\\', 'z', 'x', 'c', 'v', 'b', 'n', 'm', ',', '.', '/', RSHIFT,			/* 2a - 36 */
-	NUM_MUL, LALT, ' ', CAPSLK, F1, F2, F3, F4, F5, F6, F7, F8, F9, F10,			/* 37 - 44 */
-	NUMLK, SCRLK, NUM_7, NUM_8, NUM_9, NUM_MINUS, NUM_4, NUM_5, NUM_6, NUM_PLUS,	/* 45 - 4e */
-	NUM_1, NUM_2, NUM_3, NUM_0, NUM_DOT, SYSRQ, 0, 0, F11, F12,						/* 4d - 58 */
-	0, 0, 0, 0, 0, 0, 0,															/* 59 - 5f */
-	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,									/* 60 - 6f */
-	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0									/* 70 - 7f */
-};
 
 void kmain(struct mboot_info *mbinf)
 {
@@ -72,13 +43,6 @@
 
 
 	for(;;) {
-		char c, keypress;
-		do {
-			inb(keypress, 0x64);
-		} while(!(keypress & 1));
-		inb(c, 0x60);
-		if(!(c & 0x80)) {
-			putchar(keycodes[(int)c]);
-		}
+		halt_cpu();
 	}
 }
diff -r e6de3c6015cb -r 5f6c5751ae05 src/panic.c
--- a/src/panic.c	Sun Jul 24 18:29:24 2011 +0300
+++ b/src/panic.c	Mon Jul 25 11:29:02 2011 +0300
@@ -3,7 +3,7 @@
 #include <stdarg.h>
 #include "asmops.h"
 
-struct registers {
+struct all_registers {
 	uint32_t eax, ebx, ecx, edx;
 	uint32_t esp, ebp, esi, edi;
 	uint32_t eflags;
@@ -12,12 +12,12 @@
 };
 
 /* defined in regs.S */
-void get_regs(struct registers *regs);
+void get_regs(struct all_registers *regs);
 
 void panic(const char *fmt, ...)
 {
 	va_list ap;
-	struct registers regs;
+	struct all_registers regs;
 
 	disable_intr();
 
diff -r e6de3c6015cb -r 5f6c5751ae05 src/proc.c
--- a/src/proc.c	Sun Jul 24 18:29:24 2011 +0300
+++ b/src/proc.c	Mon Jul 25 11:29:02 2011 +0300
@@ -11,6 +11,7 @@
 	/* prepare the first process */
 
 	/* create the virtual address space for this process */
+	proc[0].ctx.pgtbl_paddr = clone_vmem();
 
 	/* allocate a chunk of memory for the process image
 	 * and copy the code of test_proc there.
@@ -28,10 +29,11 @@
 	 */
 }
 
+/*
 void save_context(struct intr_frame *ifrm)
 {
 	proc[cur_pid].ctx->regs = ifrm->regs;
 	proc[cur_pid].ctx->instr_ptr = ifrm->eip;
 	proc[cur_pid].ctx->stack_ptr = ifrm->esp;
 	proc[cur_pid].ctx->flags = ifrm->eflags;
-}
+}*/
diff -r e6de3c6015cb -r 5f6c5751ae05 src/proc.h
--- a/src/proc.h	Sun Jul 24 18:29:24 2011 +0300
+++ b/src/proc.h	Mon Jul 25 11:29:02 2011 +0300
@@ -1,6 +1,7 @@
 #ifndef PROC_H_
 #define PROC_H_
 
+#include <inttypes.h>
 #include "asmops.h"
 
 #define MAX_PROC	128
@@ -10,6 +11,7 @@
 	uint32_t instr_ptr;
 	uint32_t stack_ptr;
 	uint32_t flags;
+	uint32_t pgtbl_paddr;
 	/* TODO add FPU state */
 };
 
diff -r e6de3c6015cb -r 5f6c5751ae05 src/vm.c
--- a/src/vm.c	Sun Jul 24 18:29:24 2011 +0300
+++ b/src/vm.c	Mon Jul 25 11:29:02 2011 +0300
@@ -134,9 +134,10 @@
 	return 0;
 }
 
-void unmap_page(int vpage)
+int unmap_page(int vpage)
 {
 	uint32_t *pgtbl;
+	int res = 0;
 	int diridx = PAGE_TO_PGTBL(vpage);
 	int pgidx = PAGE_TO_PGTBL_PG(vpage);
 
@@ -157,8 +158,10 @@
 	if(0) {
 err:
 		printf("unmap_page(%d): page already not mapped\n", vpage);
+		res = -1;
 	}
 	set_intr_state(intr_state);
+	return res;
 }
 
 /* if ppg_start is -1, we allocate physical pages to map with alloc_phys_page() */
@@ -173,6 +176,18 @@
 	return 0;
 }
 
+int unmap_page_range(int vpg_start, int pgcount)
+{
+	int i, res = 0;
+
+	for(i=0; i<pgcount; i++) {
+		if(unmap_page(vpg_start + i) == -1) {
+			res = -1;
+		}
+	}
+	return res;
+}
+
 /* if paddr is 0, we allocate physical pages with alloc_phys_page() */
 int map_mem_range(uint32_t vaddr, size_t sz, uint32_t paddr, unsigned int attr)
 {
@@ -193,21 +208,39 @@
 
 uint32_t virt_to_phys(uint32_t vaddr)
 {
+	int pg;
+	uint32_t pgaddr;
+
+	if((pg = virt_to_phys_page(ADDR_TO_PAGE(vaddr))) == -1) {
+		return 0;
+	}
+	pgaddr = PAGE_TO_ADDR(pg);
+
+	return pgaddr | ADDR_TO_PGOFFS(vaddr);
+}
+
+int virt_to_phys_page(int vpg)
+{
 	uint32_t pgaddr, *pgtbl;
-	int diridx = ADDR_TO_PGTBL(vaddr);
-	int pgidx = ADDR_TO_PGTBL_PG(vaddr);
+	int diridx, pgidx;
+
+	if(vpg < 0 || vpg >= PAGE_COUNT) {
+		return -1;
+	}
+
+	diridx = PAGE_TO_PGTBL(vpg);
+	pgidx = PAGE_TO_PGTBL_PG(vpg);
 
 	if(!(pgdir[diridx] & PG_PRESENT)) {
-		panic("virt_to_phys(%x): page table %d not present\n", vaddr, diridx);
+		return -1;
 	}
 	pgtbl = PGTBL(diridx);
 
 	if(!(pgtbl[pgidx] & PG_PRESENT)) {
-		panic("virt_to_phys(%x): page %d not present\n", vaddr, ADDR_TO_PAGE(vaddr));
+		return -1;
 	}
 	pgaddr = pgtbl[pgidx] & PGENT_ADDR_MASK;
-
-	return pgaddr | ADDR_TO_PGOFFS(vaddr);
+	return ADDR_TO_PAGE(pgaddr);
 }
 
 /* allocate a contiguous block of virtual memory pages along with
@@ -266,9 +299,9 @@
 	disable_intr();
 
 	for(i=0; i<num; i++) {
-		uint32_t phys = virt_to_phys(PAGE_TO_ADDR(start + i));
-		if(phys) {
-			free_phys_page(ADDR_TO_PAGE(phys));
+		int phys_pg = virt_to_phys_page(start + i);
+		if(phys_pg != -1) {
+			free_phys_page(phys_pg);
 		}
 	}
 
@@ -393,6 +426,60 @@
 }
 
 
+/* clone_vmem makes a copy of the current page tables, thus duplicating
+ * the virtual address space.
+ *
+ * Returns the physical address of the new page directory.
+ */
+uint32_t clone_vmem(void)
+{
+	int i, dirpg, tblpg;
+	uint32_t paddr;
+	uint32_t *ndir, *ntbl;
+
+	if((dirpg = pgalloc(1, MEM_KERNEL)) == -1) {
+		panic("clone_vmem: failed to allocate page directory page\n");
+	}
+	ndir = (uint32_t*)PAGE_TO_ADDR(dirpg);
+
+	if((tblpg = pgalloc(1, MEM_KERNEL)) == -1) {
+		panic("clone_vmem: failed to allocate page table page\n");
+	}
+	ntbl = (uint32_t*)PAGE_TO_ADDR(tblpg);
+
+	/* we will allocate physical pages and map them to this virtual page
+	 * as needed in the loop below.
+	 */
+	free_phys_page(virt_to_phys(tblpg));
+
+	for(i=0; i<1024; i++) {
+		if(pgdir[i] & PG_PRESENT) {
+			paddr = alloc_phys_page();
+			map_page(tblpg, ADDR_TO_PAGE(paddr), 0);
+
+			/* copy the page table */
+			memcpy(ntbl, PGTBL(i), PGSIZE);
+
+			/* set the new page directory entry */
+			ndir[i] = paddr | (pgdir[i] & PGOFFS_MASK);
+		} else {
+			ndir[i] = 0;
+		}
+	}
+
+	paddr = virt_to_phys(dirpg);
+
+	/* unmap before freeing to avoid deallocating the physical pages */
+	unmap_page(dirpg);
+	unmap_page(tblpg);
+
+	pgfree(dirpg, 1);
+	pgfree(tblpg, 1);
+
+	return paddr;
+}
+
+
 void dbg_print_vm(int area)
 {
 	struct page_range *node;
diff -r e6de3c6015cb -r 5f6c5751ae05 src/vm.h
--- a/src/vm.h	Sun Jul 24 18:29:24 2011 +0300
+++ b/src/vm.h	Mon Jul 25 11:29:02 2011 +0300
@@ -38,9 +38,12 @@
 void init_vm(void);
 
 int map_page(int vpage, int ppage, unsigned int attr);
+int unmap_page(int vpage);
 int map_page_range(int vpg_start, int pgcount, int ppg_start, unsigned int attr);
+int unmap_page_range(int vpg_start, int pgcount);
 int map_mem_range(uint32_t vaddr, size_t sz, uint32_t paddr, unsigned int attr);
 
+int virt_to_phys_page(int vpg);
 uint32_t virt_to_phys(uint32_t vaddr);
 
 enum {
@@ -51,6 +54,8 @@
 int pgalloc(int num, int area);
 void pgfree(int start, int num);
 
+uint32_t clone_vmem(void);
+
 void dbg_print_vm(int area);
 
 #endif	/* VM_H_ */