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提交 649c423f 创建 作者: Frans Kaashoek's avatar Frans Kaashoek
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new mem layout: kernel at KERNBASE, i.e., kernel va's are not equal to pa's

上级 7a560836
隐藏空白字符变更
内嵌 并排
正在显示 包含 243 行增加 和 92 行删除
Makefile
浏览文件 @ 649c423f
......@@ -114,7 +114,7 @@ bootother: bootother.S
$(CC) $(CFLAGS) -nostdinc -I. -c bootother.S
$(LD) $(LDFLAGS) -N -e start -Ttext 0x7000 -o bootother.out bootother.o
$(OBJCOPY) -S -O binary bootother.out bootother
$(OBJDUMP) -S bootother.o > bootother.asm
$(OBJDUMP) -S bootother.out > bootother.asm
initcode: initcode.S
$(CC) $(CFLAGS) -nostdinc -I. -c initcode.S
......@@ -123,7 +123,7 @@ initcode: initcode.S
$(OBJDUMP) -S initcode.o > initcode.asm
kernel: $(OBJS) multiboot.o data.o bootother initcode
$(LD) $(LDFLAGS) -Ttext 0x100000 -e main -o kernel multiboot.o data.o $(OBJS) -b binary initcode bootother
$(LD) $(LDFLAGS) -T kernel.ld -e multiboot_entry -o kernel multiboot.o data.o $(OBJS) -b binary initcode bootother
$(OBJDUMP) -S kernel > kernel.asm
$(OBJDUMP) -t kernel | sed '1,/SYMBOL TABLE/d; s/ .* / /; /^$$/d' > kernel.sym
......
bootmain.c
浏览文件 @ 649c423f
......@@ -8,6 +8,7 @@
#include "types.h"
#include "elf.h"
#include "x86.h"
#include "memlayout.h"
#define SECTSIZE 512
......@@ -19,7 +20,7 @@ bootmain(void)
struct elfhdr *elf;
struct proghdr *ph, *eph;
void (*entry)(void);
uchar* va;
uchar *pa;
elf = (struct elfhdr*)0x10000; // scratch space
......@@ -34,15 +35,15 @@ bootmain(void)
ph = (struct proghdr*)((uchar*)elf + elf->phoff);
eph = ph + elf->phnum;
for(; ph < eph; ph++){
va = (uchar*)ph->va;
readseg(va, ph->filesz, ph->offset);
pa = (uchar*)ph->pa;
readseg(pa, ph->filesz, ph->offset);
if(ph->memsz > ph->filesz)
stosb(va + ph->filesz, 0, ph->memsz - ph->filesz);
stosb(pa + ph->filesz, 0, ph->memsz - ph->filesz);
}
// Call the entry point from the ELF header.
// Does not return!
entry = (void(*)(void))(elf->entry);
entry = (void(*)(void))(elf->entry & 0xFFFFFF); // XXX get ridd off 0xFFFFF
entry();
}
......
bootother.S
浏览文件 @ 649c423f
#include "asm.h"
#include "memlayout.h"
# Each non-boot CPU ("AP") is started up in response to a STARTUP
# IPI from the boot CPU. Section B.4.2 of the Multi-Processor
......@@ -24,10 +25,16 @@
#define CR0_PE 1
#define RELOC1(x) ((x) + KERNBASE) // same as V2P, but without casts
.code16
.globl start
start:
cli
cli
## movw $0xb800, %ax
## movw %ax, %es
## movw $65, %es:(0x0)
xorw %ax,%ax
movw %ax,%ds
......@@ -38,13 +45,14 @@ start:
movl %cr0, %eax
orl $CR0_PE, %eax
movl %eax, %cr0
//PAGEBREAK!
ljmp $(SEG_KCODE<<3), $start32
ljmpl $(SEG_KCODE<< 3), $(start32+KERNBASE)
.code32
start32:
# movw $65, 0xb8002
movw $(SEG_KDATA<<3), %ax
movw %ax, %ds
movw %ax, %es
movw %ax, %ss
......@@ -53,10 +61,10 @@ start32:
movw %ax, %gs
# switch to the stack allocated by bootothers()
movl start-4, %esp
movl RELOC1(start-4), %esp
# call mpmain()
call *(start-8)
call *(RELOC1(start)-8)
movw $0x8a00, %ax
movw %ax, %dx
......@@ -69,8 +77,8 @@ spin:
.p2align 2
gdt:
SEG_NULLASM
SEG_ASM(STA_X|STA_R, 0x0, 0xffffffff)
SEG_ASM(STA_W, 0x0, 0xffffffff)
SEG_ASM(STA_X|STA_R, -KERNBASE, 0xffffffff)
SEG_ASM(STA_W, -KERNBASE, 0xffffffff)
gdtdesc:
.word (gdtdesc - gdt - 1)
......
console.c
浏览文件 @ 649c423f
......@@ -10,6 +10,7 @@
#include "condvar.h"
#include "fs.h"
#include "file.h"
#include "memlayout.h"
#include "mmu.h"
#include "queue.h"
#include "proc.h"
......@@ -177,7 +178,7 @@ panic(char *s)
//PAGEBREAK: 50
#define BACKSPACE 0x100
#define CRTPORT 0x3d4
static ushort *crt = (ushort*)0xb8000; // CGA memory
static ushort *crt = (ushort*)P2V(0xb8000); // CGA memory
static void
cgaputc(int c)
......
defs.h
浏览文件 @ 649c423f
......@@ -73,6 +73,7 @@ extern uchar ioapicid;
void ioapicinit(void);
// kalloc.c
char* pgalloc(void);
void kinit(void);
char* kalloc(void);
void kfree(char*);
......@@ -187,6 +188,8 @@ void uartintr(void);
void uartputc(int);
// vm.c
void printpgdir(pde_t*);
void pginit(char* (*alloc)());
void seginit(void);
void kvmalloc(void);
void vmenable(void);
......
exec.c
浏览文件 @ 649c423f
#include "types.h"
#include "param.h"
#include "memlayout.h"
#include "mmu.h"
#include "spinlock.h"
#include "condvar.h"
......
fs.c
浏览文件 @ 649c423f
......@@ -605,7 +605,7 @@ namex(char *path, int nameiparent, char *name)
{
struct inode *ip, *next;
if(*path == '/')
if(*path == '/')
ip = iget(ROOTDEV, ROOTINO);
else
ip = idup(proc->cwd);
......
ide.c
浏览文件 @ 649c423f
......@@ -3,6 +3,7 @@
#include "types.h"
#include "defs.h"
#include "param.h"
#include "memlayout.h"
#include "mmu.h"
#include "spinlock.h"
#include "condvar.h"
......@@ -94,7 +95,7 @@ void
ideintr(void)
{
struct buf *b;
// Take first buffer off queue.
acquire(&idelock);
if((b = idequeue) == 0){
......
kalloc.c
浏览文件 @ 649c423f
......@@ -5,6 +5,7 @@
#include "types.h"
#include "defs.h"
#include "param.h"
#include "memlayout.h"
#include "mmu.h"
#include "spinlock.h"
#include "condvar.h"
......@@ -17,9 +18,24 @@ void kminit(void);
struct kmem kmems[NCPU];
extern char end[]; // first address after kernel loaded from ELF file
char *newend;
static int kinited __attribute__ ((aligned (CACHELINE)));
// simple page allocator to get off the ground during boot
char *
pgalloc(void)
{
if (newend == 0)
newend = end;
void *p = (void*)PGROUNDUP((uint)newend);
memset(p, 0, PGSIZE);
newend = newend + PGSIZE;
return p;
}
static void __attribute__((unused))
kmemprint(void)
{
......@@ -42,8 +58,9 @@ kfree_pool(struct kmem *m, char *v)
{
struct run *r;
if((uint)v % PGSIZE || v < end || (uint)v >= PHYSTOP)
panic("kfree");
if((uint)v % PGSIZE || v < end || v2p(v) >= PHYSTOP) {
panic("kfree_pool");
}
// Fill with junk to catch dangling refs.
if (kinited)
......@@ -83,9 +100,10 @@ kinit(void)
initlock(&kmems[c].lock, kmems[c].name);
}
p = (char*)PGROUNDUP((uint)end);
for(; p + PGSIZE <= (char*)PHYSTOP; p += PGSIZE)
kfree_pool(&kmems[((uintptr_t)p) / (PHYSTOP/NCPU)], p);
p = (char*)PGROUNDUP((uint)newend);
for(; p + PGSIZE <= (char*)p2v(PHYSTOP); p += PGSIZE) {
kfree_pool(&kmems[((uintptr_t) v2p(p)) / (PHYSTOP/NCPU)], p);
}
kminit();
kinited = 1;
}
......
main.c
浏览文件 @ 649c423f
#include "types.h"
#include "defs.h"
#include "param.h"
#include "memlayout.h"
#include "mmu.h"
#include "spinlock.h"
#include "condvar.h"
......@@ -12,6 +13,7 @@ static void bootothers(void);
static void mpmain(void);
void jmpkstack(void) __attribute__((noreturn));
void mainc(void);
static volatile int newpgdir;
// Bootstrap processor starts running C code here.
// Allocate a real stack and switch to it, first
......@@ -19,6 +21,7 @@ void mainc(void);
int
main(void)
{
pginit(pgalloc);
mpinit(); // collect info about this machine
lapicinit(mpbcpu());
seginit(); // set up segments
......@@ -49,7 +52,6 @@ mainc(void)
ioapicinit(); // another interrupt controller
consoleinit(); // I/O devices & their interrupts
uartinit(); // serial port
kvmalloc(); // initialize the kernel page table
rcuinit(); // initialize rcu module
nsinit(); // initialize name space module
pinit(); // process table
......@@ -62,6 +64,8 @@ mainc(void)
timerinit(); // uniprocessor timer
userinit(); // first user process
bootothers(); // start other processors
kvmalloc(); // new kernel page table wo. bottom mapped
newpgdir = 1;
// Finish setting up this processor in mpmain.
mpmain();
}
......@@ -70,16 +74,22 @@ mainc(void)
// Bootstrap CPU comes here from mainc().
// Other CPUs jump here from bootother.S.
static void
mpmain(void)
mpboot(void)
{
if(cpunum() != mpbcpu()){
seginit();
lapicinit(cpunum());
}
vmenable(); // turn on paging
seginit();
lapicinit(cpunum());
mpmain();
}
static void
mpmain(void)
{
cprintf("cpu%d: starting\n", cpu->id);
idtinit(); // load idt register
xchg(&cpu->booted, 1); // tell bootothers() we're up
while (!newpgdir) ; // wait until we have new page dir
switchkvm(); // switch to new page dir
scheduler(); // start running processes
}
......@@ -95,7 +105,7 @@ bootothers(void)
// Write bootstrap code to unused memory at 0x7000.
// The linker has placed the image of bootother.S in
// _binary_bootother_start.
code = (uchar*)0x7000;
code = p2v(0x7000);
memmove(code, _binary_bootother_start, (uint)_binary_bootother_size);
for(c = cpus; c < cpus+ncpu; c++){
......@@ -107,9 +117,9 @@ bootothers(void)
// its first instruction.
stack = kalloc();
*(void**)(code-4) = stack + KSTACKSIZE;
*(void**)(code-8) = mpmain;
*(void**)(code-8) = mpboot;
lapicstartap(c->id, (uint)code);
lapicstartap(c->id, v2p(code));
// Wait for cpu to finish mpmain()
while(c->booted == 0)
......
mmu.h
浏览文件 @ 649c423f
......@@ -42,6 +42,7 @@
#define CR0_CD 0x40000000 // Cache Disable
#define CR0_PG 0x80000000 // Paging
//PAGEBREAK!
// Segment Descriptor
struct segdesc {
......@@ -111,18 +112,10 @@ struct segdesc {
// construct linear address from indexes and offset
#define PGADDR(d, t, o) ((uint)((d) << PDXSHIFT | (t) << PTXSHIFT | (o)))
// turn a kernel linear address into a physical address.
// all of the kernel data structures have linear and
// physical addresses that are equal.
#define PADDR(a) ((uint)(a))
// Page directory and page table constants.
#define NPDENTRIES 1024 // page directory entries per page directory
#define NPTENTRIES 1024 // page table entries per page table
#define PGSIZE 4096 // bytes mapped by a page
#define PGSHIFT 12 // log2(PGSIZE)
#define PTXSHIFT 12 // offset of PTX in a linear address
#define PDXSHIFT 22 // offset of PDX in a linear address
......
mp.c
浏览文件 @ 649c423f
......@@ -5,6 +5,7 @@
#include "types.h"
#include "defs.h"
#include "param.h"
#include "memlayout.h"
#include "mp.h"
#include "x86.h"
#include "mmu.h"
......@@ -42,6 +43,7 @@ mpsearch1(uchar *addr, int len)
{
uchar *e, *p;
addr = p2v((uint) addr);
e = addr+len;
for(p = addr; p < e; p += sizeof(struct mp))
if(memcmp(p, "_MP_", 4) == 0 && sum(p, sizeof(struct mp)) == 0)
......@@ -86,7 +88,7 @@ mpconfig(struct mp **pmp)
if((mp = mpsearch()) == 0 || mp->physaddr == 0)
return 0;
conf = (struct mpconf*)mp->physaddr;
conf = (struct mpconf*) p2v((uint) mp->physaddr);
if(memcmp(conf, "PCMP", 4) != 0)
return 0;
if(conf->version != 1 && conf->version != 4)
......
multiboot.S
浏览文件 @ 649c423f
......@@ -15,6 +15,9 @@
# }
#include "asm.h"
#include "memlayout.h"
#define RELOC(x) ((x) - KERNBASE) // same as V2P, but without casts
#define STACK 4096
......@@ -42,7 +45,7 @@ multiboot_header:
# boot loader - bootasm.S - sets up.
.globl multiboot_entry
multiboot_entry:
lgdt gdtdesc
lgdt RELOC(gdtdesc)
ljmp $(SEG_KCODE<<3), $mbstart32
mbstart32:
......@@ -65,11 +68,11 @@ spin:
.p2align 2 # force 4 byte alignment
gdt:
SEG_NULLASM # null seg
SEG_ASM(STA_X|STA_R, 0x0, 0xffffffff) # code seg
SEG_ASM(STA_W, 0x0, 0xffffffff) # data seg
SEG_ASM(STA_X|STA_R, -KERNBASE, 0xffffffff) # code seg
SEG_ASM(STA_W, -KERNBASE, 0xffffffff) # data seg
gdtdesc:
.word (gdtdesc - gdt - 1) # sizeof(gdt) - 1
.long gdt # address gdt
.long RELOC(gdt) # address gdt
.comm stack, STACK
param.h
浏览文件 @ 649c423f
......@@ -7,8 +7,6 @@
#define NINODE 50 // maximum number of active i-nodes
#define NDEV 10 // maximum major device number
#define ROOTDEV 1 // device number of file system root disk
#define USERTOP 0xA0000 // end of user address space
#define PHYSTOP 0x10000000 // use phys mem up to here as free pool
#define MAXARG 32 // max exec arguments
#define MAXNAME 16 // max string names
#define MINCYCTHRESH 1000000 // min cycles a proc executes on a core before allowed to be stolen
......
proc.c
浏览文件 @ 649c423f
#include "types.h"
#include "defs.h"
#include "param.h"
#include "memlayout.h"
#include "mmu.h"
#include "x86.h"
#include "spinlock.h"
......@@ -506,6 +507,7 @@ scheduler(void)
// cprintf("%d: no longer idle, running %d\n", cpu->id, p->pid);
idle[cpu->id] = 0;
}
release(&runq->lock);
// Switch to chosen process. It is the process's job
......@@ -560,6 +562,7 @@ sched(void)
proc->curcycles += rdtsc() - proc->tsc;
mtrace_fcall_register(proc->pid, 0, 0, mtrace_pause);
mtrace_call_set(0, cpunum());
swtch(&proc->context, cpu->scheduler);
cpu->intena = intena;
}
......@@ -587,7 +590,7 @@ forkret(void)
// in which to call cv_sleep().
if(proc->cwd == 0)
proc->cwd = namei("/");
// Return to "caller", actually trapret (see allocproc).
}
......
proc.h
浏览文件 @ 649c423f
......@@ -143,7 +143,7 @@ extern struct ns *nspid;
// holding those two variables in the local cpu's struct cpu.
// This is similar to how thread-local variables are implemented
// in thread libraries such as Linux pthreads.
extern struct cpu *cpu __asm("%gs:0"); // &cpus[cpunum()]
extern struct cpu *cpu __asm("%gs:0"); // &cpus[cpunum()].cpu
extern struct proc *proc __asm("%gs:4"); // cpus[cpunum()].proc
extern struct kmem *kmem __asm("%gs:8"); // &kmems[cpunum()]
extern struct runq *runq __asm("%gs:12"); // &runqs[cpunum()]
extern struct kmem *kmem __asm("%gs:8"); // &cpu[cpunum()].kmem
extern struct runq *runq __asm("%gs:12"); // &cpu[cpunum()].runq
spinlock.c
浏览文件 @ 649c423f
......@@ -4,6 +4,7 @@
#include "defs.h"
#include "param.h"
#include "x86.h"
#include "memlayout.h"
#include "mmu.h"
#include "spinlock.h"
#include "condvar.h"
......@@ -94,7 +95,7 @@ getcallerpcs(void *v, uint pcs[])
ebp = (uint*)v - 2;
for(i = 0; i < 10; i++){
if(ebp == 0 || ebp < (uint*)0x100000 || ebp == (uint*)0xffffffff)
if(ebp == 0 || ebp < (uint*)KERNBASE || ebp == (uint*)0xffffffff)
break;
pcs[i] = ebp[1]; // saved %eip
ebp = (uint*)ebp[0]; // saved %ebp
......
syscall.c
浏览文件 @ 649c423f
#include "types.h"
#include "defs.h"
#include "param.h"
#include "memlayout.h"
#include "mmu.h"
#include "spinlock.h"
#include "condvar.h"
......
sysproc.c
浏览文件 @ 649c423f
......@@ -2,6 +2,7 @@
#include "x86.h"
#include "defs.h"
#include "param.h"
#include "memlayout.h"
#include "mmu.h"
#include "spinlock.h"
#include "condvar.h"
......@@ -135,7 +136,7 @@ sys_unmap(void)
(void*) (PGROUNDDOWN(addr)),
(void*) (PGROUNDDOWN(addr)+PGROUNDUP(len)));
cli();
lcr3(PADDR(proc->vmap->pgdir));
lcr3(v2p(proc->vmap->pgdir));
for (uint i = 0; i < ncpu; i++)
if (i != cpu->id)
lapic_tlbflush(i);
......
trap.c
浏览文件 @ 649c423f
#include "types.h"
#include "defs.h"
#include "param.h"
#include "memlayout.h"
#include "mmu.h"
#include "spinlock.h"
#include "condvar.h"
......@@ -32,7 +33,7 @@ tvinit(void)
void
idtinit(void)
{
lidt(idt, sizeof(idt));
lidt(idt, sizeof(idt));
}
//PAGEBREAK: 41
......@@ -48,7 +49,6 @@ trap(struct trapframe *tf)
exit();
return;
}
switch(tf->trapno){
case T_IRQ0 + IRQ_TIMER:
if(cpu->id == 0){
......
vm.c
浏览文件 @ 649c423f
......@@ -2,6 +2,7 @@
#include "types.h"
#include "defs.h"
#include "x86.h"
#include "memlayout.h"
#include "mmu.h"
#include "spinlock.h"
#include "condvar.h"
......@@ -14,6 +15,64 @@ extern char data[]; // defined in data.S
static pde_t *kpgdir __attribute__ ((aligned (CACHELINE))); // for use in scheduler()
struct segdesc gdt[NSEGS];
// page map for during boot
static void
pgmap(void *va, void *last, uint pa)
{
pde_t *pde;
pte_t *pgtab;
pte_t *pte;
for(;;){
pde = &kpgdir[PDX(va)];
pde_t pdev = *pde;
if (pdev == 0) {
pgtab = (pte_t *) pgalloc();
*pde = v2p(pgtab) | PTE_P | PTE_W;
} else {
pgtab = (pte_t*)p2v(PTE_ADDR(pdev));
}
pte = &pgtab[PTX(va)];
*pte = pa | PTE_W | PTE_P;
if(va == last)
break;
va += PGSIZE;
pa += PGSIZE;
}
}
// set up a page table to get off the ground
void
pginit(char* (*alloc)(void))
{
uint cr0;
kpgdir = (pde_t *) alloc();
pgmap((void *) 0, (void *) PHYSTOP, 0);
pgmap((void *) KERNBASE, (void *) (KERNBASE+PHYSTOP), 0);
pgmap((void*)0xFE000000, 0, 0xFE000000);
switchkvm(); // load kpgdir into cr3
cr0 = rcr0();
cr0 |= CR0_PG;
lcr0(cr0); // paging on
// new gdt
gdt[SEG_KCODE] = SEG(STA_X|STA_R, 0, 0xffffffff, 0);
gdt[SEG_KDATA] = SEG(STA_W, 0, 0xffffffff, 0);
lgdt((void *)v2p(gdt), sizeof(gdt));
loadgs(SEG_KDATA << 3);
loadfs(SEG_KDATA << 3);
loades(SEG_KDATA << 3);
loadds(SEG_KDATA << 3);
loadss(SEG_KDATA << 3);
__asm volatile("ljmp %0,$1f\n 1:\n" :: "i" (SEG_KCODE << 3)); // reload cs
}
// Set up CPU's kernel segment descriptors.
// Run once at boot time on each CPU.
void
......@@ -34,7 +93,8 @@ seginit(void)
// Map cpu, curproc, kmem, runq
c->gdt[SEG_KCPU] = SEG(STA_W, &c->cpu, 16, 0);
lgdt(c->gdt, sizeof(c->gdt));
// lgt((void *) v2p((void*)(c->gdt)), sizeof(c->gdt));
lgdt((void *)(c->gdt), sizeof(c->gdt));
loadgs(SEG_KCPU << 3);
// Initialize cpu-local storage.
......@@ -44,6 +104,31 @@ seginit(void)
runq = &runqs[cpunum()];
}
void
printpgdir(pde_t *pgdir)
{
pde_t *pde;
pte_t *pgtab;
pte_t pte;
for (uint i = 0; i < NPDENTRIES; i++) {
pde = &pgdir[i];
pde_t pdev = *pde;
if (pdev & PTE_P) {
pgtab = (pte_t*)p2v(PTE_ADDR(pdev));
cprintf("%d: p 0x%x v 0x%x\n", i, PTE_ADDR(pdev), pgtab);
for (uint j = 0; j < NPTENTRIES; j++) {
pte = pgtab[j];
if (pte & PTE_P) {
void *pg = p2v(PTE_ADDR(pte));
if (pg != 0)
; // cprintf(" %d: 0x%x v 0x%x\n", j, pte, pg);
}
}
}
}
}
// Return the address of the PTE in page table pgdir
// that corresponds to linear address va. If create!=0,
// create any required page table pages.
......@@ -57,7 +142,7 @@ walkpgdir(pde_t *pgdir, const void *va, int create)
pde = &pgdir[PDX(va)];
pde_t pdev = *pde;
if(pdev & PTE_P){
pgtab = (pte_t*)PTE_ADDR(pdev);
pgtab = (pte_t*)p2v(PTE_ADDR(pdev));
} else {
if(!create || (pgtab = (pte_t*)kalloc()) == 0)
return 0;
......@@ -66,7 +151,7 @@ walkpgdir(pde_t *pgdir, const void *va, int create)
// The permissions here are overly generous, but they can
// be further restricted by the permissions in the page table
// entries, if necessary.
if (!__sync_bool_compare_and_swap(pde, pdev, PADDR(pgtab) | PTE_P | PTE_W | PTE_U)) {
if (!__sync_bool_compare_and_swap(pde, pdev, v2p(pgtab) | PTE_P | PTE_W | PTE_U)) {
kfree((void*) pgtab);
goto retry;
}
......@@ -82,7 +167,7 @@ mappages(pde_t *pgdir, void *la, uint size, uint pa, int perm)
{
char *a, *last;
pte_t *pte;
a = PGROUNDDOWN(la);
last = PGROUNDDOWN(la + size - 1);
for(;;){
......@@ -136,8 +221,6 @@ clearpages(pde_t *pgdir, void *begin, void *end)
}
}
// The mappings from logical to linear are one to one (i.e.,
// segmentation doesn't do anything).
// There is one page table per process, plus one that's used
// when a CPU is not running any process (kpgdir).
// A user process uses the same page table as the kernel; the
......@@ -159,14 +242,16 @@ clearpages(pde_t *pgdir, void *begin, void *end)
// (both in physical memory and in the kernel's virtual address
// space).
static struct kmap {
void *p;
void *e;
void *l;
uint p;
uint e;
int perm;
} kmap[] = {
{(void*)USERTOP, (void*)0x100000, PTE_W}, // I/O space
{(void*)0x100000, data, 0 }, // kernel text, rodata
{data, (void*)PHYSTOP, PTE_W}, // kernel data, memory
{(void*)0xFE000000, 0, PTE_W}, // device mappings
{ (void *)IOSPACEB, IOSPACEB, IOSPACEE, PTE_W}, // I/O space
{ P2V(IOSPACEB), IOSPACEB, IOSPACEE, PTE_W}, // I/O space
{ (void *)KERNLINK, V2P(KERNLINK), V2P(data), 0}, // kernel text, rodata
{ data, V2P(data), PHYSTOP, PTE_W}, // kernel data, memory
{ (void*)0xFE000000, 0xFE000000, 0, PTE_W}, // device mappings
};
// Set up kernel part of a page table.
......@@ -181,7 +266,7 @@ setupkvm(void)
memset(pgdir, 0, PGSIZE);
k = kmap;
for(k = kmap; k < &kmap[NELEM(kmap)]; k++)
if(mappages(pgdir, k->p, k->e - k->p, (uint)k->p, k->perm) < 0)
if(mappages(pgdir, k->l, k->e - k->p, (uint)k->p, k->perm) < 0)
return 0;
return pgdir;
......@@ -193,6 +278,7 @@ void
kvmalloc(void)
{
kpgdir = setupkvm();
switchkvm();
}
// Turn on paging.
......@@ -202,9 +288,20 @@ vmenable(void)
uint cr0;
switchkvm(); // load kpgdir into cr3
cr0 = rcr0();
cr0 |= CR0_PG;
lcr0(cr0);
struct cpu *c = &cpus[0];
lgdt((void *)v2p((void *)(c->gdt)), sizeof(c->gdt));
loadgs(SEG_KCPU << 3);
loadfs(SEG_KDATA << 3);
loades(SEG_KDATA << 3);
loadds(SEG_KDATA << 3);
loadss(SEG_KDATA << 3);
__asm volatile("ljmp %0,$1f\n 1:\n" :: "i" (SEG_KCODE << 3)); // reload cs
}
// Switch h/w page table register to the kernel-only page table,
......@@ -212,7 +309,7 @@ vmenable(void)
void
switchkvm(void)
{
lcr3(PADDR(kpgdir)); // switch to the kernel page table
lcr3(v2p(kpgdir)); // switch to the kernel page table
}
// Switch TSS and h/w page table to correspond to process p.
......@@ -223,11 +320,11 @@ switchuvm(struct proc *p)
cpu->gdt[SEG_TSS] = SEG16(STS_T32A, &cpu->ts, sizeof(cpu->ts)-1, 0);
cpu->gdt[SEG_TSS].s = 0;
cpu->ts.ss0 = SEG_KDATA << 3;
cpu->ts.esp0 = (uint)proc->kstack + KSTACKSIZE;
cpu->ts.esp0 = (uint) proc->kstack + KSTACKSIZE;
ltr(SEG_TSS << 3);
if(p->vmap == 0 || p->vmap->pgdir == 0)
panic("switchuvm: no vmap/pgdir");
lcr3(PADDR(p->vmap->pgdir)); // switch to new address space
lcr3(v2p(p->vmap->pgdir)); // switch to new address space
popcli();
}
......@@ -242,7 +339,7 @@ freevm(pde_t *pgdir)
panic("freevm: no pgdir");
for(i = 0; i < NPDENTRIES; i++){
if(pgdir[i] & PTE_P)
kfree((char*)PTE_ADDR(pgdir[i]));
kfree(p2v(PTE_ADDR(pgdir[i])));
}
kfree((char*)pgdir);
}
......@@ -498,7 +595,7 @@ vmap_copy(struct vmap *m, int share)
__sync_fetch_and_add(&c->e[i].n->ref, 1);
}
if (share)
lcr3(PADDR(m->pgdir)); // Reload hardware page table
lcr3(v2p(m->pgdir)); // Reload hardware page table
release(&m->lock);
return c;
......@@ -534,21 +631,6 @@ vmn_load(struct vmnode *vmn, struct inode *ip, uint offset, uint sz)
}
}
//PAGEBREAK!
// Map user virtual address to kernel physical address.
char*
uva2ka(pde_t *pgdir, char *uva)
{
pte_t *pte;
pte = walkpgdir(pgdir, uva, 0);
if((*pte & PTE_P) == 0)
return 0;
if((*pte & PTE_U) == 0)
return 0;
return (char*)PTE_ADDR(*pte);
}
// Copy len bytes from p to user address va in vmap.
// Most useful when vmap is not the current page table.
int
......@@ -634,7 +716,7 @@ pagefault_wcow(struct vmap *vmap, uint va, pte_t *pte, struct vma *m, uint npg)
// Update the hardware page tables to reflect the change to the vma
clearpages(vmap->pgdir, (void *) m->va_start, (void *) m->va_end);
pte = walkpgdir(vmap->pgdir, (const void *)va, 0);
*pte = PADDR(m->n->page[npg]) | PTE_P | PTE_U | PTE_W;
*pte = v2p(m->n->page[npg]) | PTE_P | PTE_U | PTE_W;
// drop my ref to vmnode
vmn_decref(o);
return 0;
......@@ -660,14 +742,14 @@ pagefault(struct vmap *vmap, uint va, uint err)
return -1;
}
} else if (m->va_type == COW) {
*pte = PADDR(m->n->page[npg]) | PTE_P | PTE_U | PTE_COW;
*pte = v2p(m->n->page[npg]) | PTE_P | PTE_U | PTE_COW;
} else {
if (m->n->ref != 1) {
panic("pagefault");
}
*pte = PADDR(m->n->page[npg]) | PTE_P | PTE_U | PTE_W;
*pte = v2p(m->n->page[npg]) | PTE_P | PTE_U | PTE_W;
}
lcr3(PADDR(vmap->pgdir)); // Reload hardware page tables
lcr3(v2p(vmap->pgdir)); // Reload hardware page tables
release(&m->lock);
return 1;
}
x86.h
浏览文件 @ 649c423f
......@@ -97,6 +97,30 @@ loadgs(ushort v)
__asm volatile("movw %0, %%gs" : : "r" (v));
}
static inline void
loadfs(ushort v)
{
__asm volatile("movw %0, %%fs" : : "r" (v));
}
static inline void
loades(ushort v)
{
__asm volatile("movw %0, %%es" : : "r" (v));
}
static inline void
loadds(ushort v)
{
__asm volatile("movw %0, %%ds" : : "r" (v));
}
static inline void
loadss(ushort v)
{
__asm volatile("movw %0, %%ss" : : "r" (v));
}
static inline uint
rebp(void)
{
......
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