Map kernel high
Very important to give qemu memory through PHYSTOP :(
This commit is contained in:
Frans Kaashoek
parent
dccb915282
commit
9aa0337dc1
20 changed files with 208 additions and 71 deletions
4
Makefile
4
Makefile
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@ -109,7 +109,7 @@ initcode: initcode.S
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$(OBJDUMP) -S initcode.o > initcode.asm
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kernel: $(OBJS) multiboot.o data.o bootother initcode
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$(LD) $(LDFLAGS) -Ttext 0x100000 -e main -o kernel multiboot.o data.o $(OBJS) -b binary initcode bootother
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$(LD) $(LDFLAGS) -T kernel.ld -e multiboot_entry -o kernel multiboot.o data.o $(OBJS) -b binary initcode bootother
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$(OBJDUMP) -S kernel > kernel.asm
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$(OBJDUMP) -t kernel | sed '1,/SYMBOL TABLE/d; s/ .* / /; /^$$/d' > kernel.sym
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@ -200,7 +200,7 @@ QEMUGDB = $(shell if $(QEMU) -help | grep -q '^-gdb'; \
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ifndef CPUS
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CPUS := 2
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endif
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QEMUOPTS = -hdb fs.img xv6.img -smp $(CPUS)
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QEMUOPTS = -hdb fs.img xv6.img -smp $(CPUS) -m 512
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qemu: fs.img xv6.img
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$(QEMU) -serial mon:stdio $(QEMUOPTS)
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11
bootmain.c
11
bootmain.c
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@ -8,6 +8,7 @@
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#include "types.h"
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#include "elf.h"
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#include "x86.h"
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#include "memlayout.h"
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#define SECTSIZE 512
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@ -19,7 +20,7 @@ bootmain(void)
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struct elfhdr *elf;
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struct proghdr *ph, *eph;
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void (*entry)(void);
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uchar* va;
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uchar* pa;
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elf = (struct elfhdr*)0x10000; // scratch space
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@ -34,15 +35,15 @@ bootmain(void)
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ph = (struct proghdr*)((uchar*)elf + elf->phoff);
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eph = ph + elf->phnum;
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for(; ph < eph; ph++){
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va = (uchar*)ph->va;
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readseg(va, ph->filesz, ph->offset);
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pa = (uchar*)ph->pa;
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readseg(pa, ph->filesz, ph->offset);
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if(ph->memsz > ph->filesz)
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stosb(va + ph->filesz, 0, ph->memsz - ph->filesz);
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stosb(pa + ph->filesz, 0, ph->memsz - ph->filesz);
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}
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// Call the entry point from the ELF header.
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// Does not return!
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entry = (void(*)(void))(elf->entry);
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entry = (void(*)(void))(elf->entry & 0xFFFFFF);
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entry();
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}
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14
bootother.S
14
bootother.S
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@ -1,4 +1,5 @@
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#include "asm.h"
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#include "memlayout.h"
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# Each non-boot CPU ("AP") is started up in response to a STARTUP
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# IPI from the boot CPU. Section B.4.2 of the Multi-Processor
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@ -24,6 +25,8 @@
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#define CR0_PE 1
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#define RELOC1(x) ((x) + KERNBASE) // same as V2P, but without casts
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.code16
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.globl start
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start:
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@ -40,7 +43,7 @@ start:
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movl %eax, %cr0
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//PAGEBREAK!
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ljmp $(SEG_KCODE<<3), $start32
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ljmpl $(SEG_KCODE<<3), $(start32+KERNBASE)
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.code32
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start32:
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@ -53,10 +56,10 @@ start32:
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movw %ax, %gs
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# switch to the stack allocated by bootothers()
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movl start-4, %esp
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movl RELOC1(start-4), %esp
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# call mpmain()
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call *(start-8)
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call *(RELOC1(start)-8)
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movw $0x8a00, %ax
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movw %ax, %dx
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@ -69,8 +72,9 @@ spin:
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.p2align 2
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gdt:
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SEG_NULLASM
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SEG_ASM(STA_X|STA_R, 0x0, 0xffffffff)
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SEG_ASM(STA_W, 0x0, 0xffffffff)
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SEG_ASM(STA_X|STA_R, -KERNBASE, 0xffffffff)
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SEG_ASM(STA_W, -KERNBASE, 0xffffffff)
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gdtdesc:
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.word (gdtdesc - gdt - 1)
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@ -9,6 +9,7 @@
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#include "spinlock.h"
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#include "fs.h"
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#include "file.h"
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#include "memlayout.h"
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#include "mmu.h"
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#include "proc.h"
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#include "x86.h"
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@ -60,6 +61,9 @@ cprintf(char *fmt, ...)
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if(locking)
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acquire(&cons.lock);
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if (fmt == 0)
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panic("null fmt");
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argp = (uint*)(void*)(&fmt + 1);
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state = 0;
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for(i = 0; (c = fmt[i] & 0xff) != 0; i++){
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@ -121,7 +125,7 @@ panic(char *s)
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//PAGEBREAK: 50
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#define BACKSPACE 0x100
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#define CRTPORT 0x3d4
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static ushort *crt = (ushort*)0xb8000; // CGA memory
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static ushort *crt = (ushort*)P2V(0xb8000); // CGA memory
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static void
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cgaputc(int c)
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2
defs.h
2
defs.h
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@ -62,6 +62,7 @@ extern uchar ioapicid;
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void ioapicinit(void);
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// kalloc.c
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char* pgalloc(void);
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char* kalloc(void);
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void kfree(char*);
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void kinit(void);
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@ -160,6 +161,7 @@ void uartintr(void);
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void uartputc(int);
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// vm.c
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void pginit(char* (*alloc)());
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void seginit(void);
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void kvmalloc(void);
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void vmenable(void);
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1
exec.c
1
exec.c
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@ -1,5 +1,6 @@
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#include "types.h"
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#include "param.h"
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#include "memlayout.h"
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#include "mmu.h"
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#include "proc.h"
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#include "defs.h"
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1
ide.c
1
ide.c
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@ -3,6 +3,7 @@
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#include "types.h"
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#include "defs.h"
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#include "param.h"
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#include "memlayout.h"
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#include "mmu.h"
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#include "proc.h"
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#include "x86.h"
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22
kalloc.c
22
kalloc.c
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@ -5,6 +5,7 @@
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#include "types.h"
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#include "defs.h"
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#include "param.h"
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#include "memlayout.h"
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#include "mmu.h"
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#include "spinlock.h"
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@ -18,6 +19,20 @@ struct {
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} kmem;
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extern char end[]; // first address after kernel loaded from ELF file
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char *newend;
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// simple page allocator to get off the ground during boot
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char *
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pgalloc(void)
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{
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if (newend == 0)
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newend = end;
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void *p = (void*)PGROUNDUP((uint)newend);
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memset(p, 0, PGSIZE);
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newend = newend + PGSIZE;
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return p;
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}
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// Initialize free list of physical pages.
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void
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@ -26,8 +41,8 @@ kinit(void)
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char *p;
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initlock(&kmem.lock, "kmem");
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p = (char*)PGROUNDUP((uint)end);
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for(; p + PGSIZE <= (char*)PHYSTOP; p += PGSIZE)
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p = (char*)PGROUNDUP((uint)newend);
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for(; p + PGSIZE <= (char*)p2v(PHYSTOP); p += PGSIZE)
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kfree(p);
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}
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@ -41,7 +56,7 @@ kfree(char *v)
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{
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struct run *r;
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if((uint)v % PGSIZE || v < end || (uint)v >= PHYSTOP)
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if((uint)v % PGSIZE || v < end || v2p(v) >= PHYSTOP)
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panic("kfree");
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// Fill with junk to catch dangling refs.
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@ -67,6 +82,7 @@ kalloc(void)
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if(r)
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kmem.freelist = r->next;
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release(&kmem.lock);
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cprintf("kalloc: 0x%x\n", r);
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return (char*)r;
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}
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33
main.c
33
main.c
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@ -1,6 +1,7 @@
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#include "types.h"
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#include "defs.h"
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#include "param.h"
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#include "memlayout.h"
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#include "mmu.h"
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#include "proc.h"
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#include "x86.h"
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@ -9,6 +10,8 @@ static void bootothers(void);
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static void mpmain(void);
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void jmpkstack(void) __attribute__((noreturn));
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void mainc(void);
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static volatile int newpgdir;
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// Bootstrap processor starts running C code here.
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// Allocate a real stack and switch to it, first
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@ -16,6 +19,7 @@ void mainc(void);
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int
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main(void)
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{
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pginit(pgalloc);
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mpinit(); // collect info about this machine
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lapicinit(mpbcpu());
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seginit(); // set up segments
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@ -46,7 +50,6 @@ mainc(void)
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ioapicinit(); // another interrupt controller
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consoleinit(); // I/O devices & their interrupts
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uartinit(); // serial port
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kvmalloc(); // initialize the kernel page table
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pinit(); // process table
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tvinit(); // trap vectors
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binit(); // buffer cache
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@ -57,25 +60,35 @@ mainc(void)
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timerinit(); // uniprocessor timer
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userinit(); // first user process
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bootothers(); // start other processors
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kvmalloc(); // new kernel page table wo. bottom mapped
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newpgdir = 1;
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// Finish setting up this processor in mpmain.
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mpmain();
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}
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// Common CPU setup code.
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// Bootstrap CPU comes here from mainc().
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// Other CPUs jump here from bootother.S.
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static void
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mpboot(void)
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{
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vmenable(); // turn on paging
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seginit();
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lapicinit(cpunum());
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mpmain();
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}
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// Common CPU setup code.
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// Bootstrap CPU comes here from mainc().
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// Other CPUs jump here from bootother.S.
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static void
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mpmain(void)
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{
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if(cpunum() != mpbcpu()){
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seginit();
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lapicinit(cpunum());
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}
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vmenable(); // turn on paging
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cprintf("cpu%d: starting\n", cpu->id);
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idtinit(); // load idt register
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xchg(&cpu->booted, 1); // tell bootothers() we're up
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while (!newpgdir) ; // wait until we have new page dir
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switchkvm(); // switch to new page dir
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scheduler(); // start running processes
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}
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@ -91,7 +104,7 @@ bootothers(void)
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// Write bootstrap code to unused memory at 0x7000.
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// The linker has placed the image of bootother.S in
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// _binary_bootother_start.
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code = (uchar*)0x7000;
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code = p2v(0x7000);
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memmove(code, _binary_bootother_start, (uint)_binary_bootother_size);
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for(c = cpus; c < cpus+ncpu; c++){
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@ -103,9 +116,9 @@ bootothers(void)
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// its first instruction.
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stack = kalloc();
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*(void**)(code-4) = stack + KSTACKSIZE;
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*(void**)(code-8) = mpmain;
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*(void**)(code-8) = mpboot;
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lapicstartap(c->id, (uint)code);
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lapicstartap(c->id, v2p(code));
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// Wait for cpu to finish mpmain()
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while(c->booted == 0)
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8
mmu.h
8
mmu.h
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@ -106,18 +106,10 @@ struct segdesc {
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// construct linear address from indexes and offset
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#define PGADDR(d, t, o) ((uint)((d) << PDXSHIFT | (t) << PTXSHIFT | (o)))
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// turn a kernel linear address into a physical address.
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// all of the kernel data structures have linear and
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// physical addresses that are equal.
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#define PADDR(a) ((uint)(a))
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// Page directory and page table constants.
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#define NPDENTRIES 1024 // page directory entries per page directory
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#define NPTENTRIES 1024 // page table entries per page table
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#define PGSIZE 4096 // bytes mapped by a page
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#define PGSHIFT 12 // log2(PGSIZE)
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#define PTXSHIFT 12 // offset of PTX in a linear address
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#define PDXSHIFT 22 // offset of PDX in a linear address
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4
mp.c
4
mp.c
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@ -5,6 +5,7 @@
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#include "types.h"
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#include "defs.h"
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#include "param.h"
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#include "memlayout.h"
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#include "mp.h"
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#include "x86.h"
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#include "mmu.h"
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@ -39,6 +40,7 @@ mpsearch1(uchar *addr, int len)
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{
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uchar *e, *p;
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addr = p2v((uint) addr);
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e = addr+len;
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for(p = addr; p < e; p += sizeof(struct mp))
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if(memcmp(p, "_MP_", 4) == 0 && sum(p, sizeof(struct mp)) == 0)
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@ -83,7 +85,7 @@ mpconfig(struct mp **pmp)
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if((mp = mpsearch()) == 0 || mp->physaddr == 0)
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return 0;
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conf = (struct mpconf*)mp->physaddr;
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conf = (struct mpconf*) p2v((uint) mp->physaddr);
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if(memcmp(conf, "PCMP", 4) != 0)
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return 0;
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if(conf->version != 1 && conf->version != 4)
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11
multiboot.S
11
multiboot.S
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@ -15,6 +15,9 @@
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# }
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#include "asm.h"
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#include "memlayout.h"
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#define RELOC(x) ((x) - KERNBASE) // same as V2P, but without casts
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#define STACK 4096
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@ -42,7 +45,7 @@ multiboot_header:
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# boot loader - bootasm.S - sets up.
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.globl multiboot_entry
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multiboot_entry:
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lgdt gdtdesc
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lgdt RELOC(gdtdesc)
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ljmp $(SEG_KCODE<<3), $mbstart32
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mbstart32:
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@ -65,11 +68,11 @@ spin:
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.p2align 2 # force 4 byte alignment
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gdt:
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SEG_NULLASM # null seg
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SEG_ASM(STA_X|STA_R, 0x0, 0xffffffff) # code seg
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SEG_ASM(STA_W, 0x0, 0xffffffff) # data seg
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SEG_ASM(STA_X|STA_R, -KERNBASE, 0xffffffff) # code seg
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SEG_ASM(STA_W, -KERNBASE, 0xffffffff) # data seg
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gdtdesc:
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.word (gdtdesc - gdt - 1) # sizeof(gdt) - 1
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.long gdt # address gdt
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.long RELOC(gdt) # address gdt
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.comm stack, STACK
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2
param.h
2
param.h
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@ -7,8 +7,6 @@
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#define NINODE 50 // maximum number of active i-nodes
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#define NDEV 10 // maximum major device number
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#define ROOTDEV 1 // device number of file system root disk
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#define USERTOP 0xA0000 // end of user address space
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#define PHYSTOP 0x1000000 // use phys mem up to here as free pool
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#define MAXARG 32 // max exec arguments
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#define LOGSIZE 10 // size of log
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1
proc.c
1
proc.c
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@ -1,6 +1,7 @@
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#include "types.h"
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#include "defs.h"
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#include "param.h"
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#include "memlayout.h"
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#include "mmu.h"
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#include "x86.h"
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#include "proc.h"
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@ -4,6 +4,7 @@
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#include "defs.h"
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#include "param.h"
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#include "x86.h"
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#include "memlayout.h"
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#include "mmu.h"
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#include "proc.h"
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#include "spinlock.h"
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@ -71,7 +72,7 @@ getcallerpcs(void *v, uint pcs[])
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ebp = (uint*)v - 2;
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for(i = 0; i < 10; i++){
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if(ebp == 0 || ebp < (uint*)0x100000 || ebp == (uint*)0xffffffff)
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if(ebp == 0 || ebp < (uint*)KERNBASE || ebp == (uint*)0xffffffff)
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break;
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pcs[i] = ebp[1]; // saved %eip
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ebp = (uint*)ebp[0]; // saved %ebp
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|
|
|
|||
|
|
@ -1,6 +1,7 @@
|
|||
#include "types.h"
|
||||
#include "defs.h"
|
||||
#include "param.h"
|
||||
#include "memlayout.h"
|
||||
#include "mmu.h"
|
||||
#include "proc.h"
|
||||
#include "x86.h"
|
||||
|
|
|
|||
|
|
@ -2,6 +2,7 @@
|
|||
#include "x86.h"
|
||||
#include "defs.h"
|
||||
#include "param.h"
|
||||
#include "memlayout.h"
|
||||
#include "mmu.h"
|
||||
#include "proc.h"
|
||||
|
||||
|
|
|
|||
1
trap.c
1
trap.c
|
|
@ -1,6 +1,7 @@
|
|||
#include "types.h"
|
||||
#include "defs.h"
|
||||
#include "param.h"
|
||||
#include "memlayout.h"
|
||||
#include "mmu.h"
|
||||
#include "proc.h"
|
||||
#include "x86.h"
|
||||
|
|
|
|||
129
vm.c
129
vm.c
|
|
@ -2,20 +2,71 @@
|
|||
#include "types.h"
|
||||
#include "defs.h"
|
||||
#include "x86.h"
|
||||
#include "memlayout.h"
|
||||
#include "mmu.h"
|
||||
#include "proc.h"
|
||||
#include "elf.h"
|
||||
|
||||
extern char data[]; // defined in data.S
|
||||
|
||||
static pde_t *kpgdir; // for use in scheduler()
|
||||
struct segdesc gdt[NSEGS];
|
||||
|
||||
// Allocate one page table for the machine for the kernel address
|
||||
// space for scheduler processes.
|
||||
void
|
||||
kvmalloc(void)
|
||||
|
||||
// page map for during boot
|
||||
// XXX build a static page table in assembly
|
||||
static void
|
||||
pgmap(void *va, void *last, uint pa)
|
||||
{
|
||||
kpgdir = setupkvm();
|
||||
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); // map pa 0 at va 0
|
||||
pgmap((void *) KERNBASE, (void *) (KERNBASE+PHYSTOP), 0); // map pa 0 at va KERNBASE
|
||||
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.
|
||||
|
|
@ -57,7 +108,7 @@ walkpgdir(pde_t *pgdir, const void *va, int create)
|
|||
|
||||
pde = &pgdir[PDX(va)];
|
||||
if(*pde & PTE_P){
|
||||
pgtab = (pte_t*)PTE_ADDR(*pde);
|
||||
pgtab = (pte_t*)p2v(PTE_ADDR(*pde));
|
||||
} else {
|
||||
if(!create || (pgtab = (pte_t*)kalloc()) == 0)
|
||||
return 0;
|
||||
|
|
@ -66,7 +117,7 @@ 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.
|
||||
*pde = PADDR(pgtab) | PTE_P | PTE_W | PTE_U;
|
||||
*pde = v2p(pgtab) | PTE_P | PTE_W | PTE_U;
|
||||
}
|
||||
return &pgtab[PTX(va)];
|
||||
}
|
||||
|
|
@ -105,29 +156,30 @@ mappages(pde_t *pgdir, void *la, uint size, uint pa, int perm)
|
|||
// page protection bits prevent it from using anything other
|
||||
// than its memory.
|
||||
//
|
||||
//
|
||||
// setupkvm() and exec() set up every page table like this:
|
||||
// 0..640K : user memory (text, data, stack, heap)
|
||||
// 640K..1M : mapped direct (for IO space)
|
||||
// 1M..end : mapped direct (for the kernel's text and data)
|
||||
// end..PHYSTOP : mapped direct (kernel heap and user pages)
|
||||
// 0..KERNBASE : user memory (text, data, stack, heap), mapped to some phys mem
|
||||
// KERNBASE+640K..KERNBASE+1M: mapped to 640K..1M
|
||||
// KERNBASE+1M..KERNBASE+end : mapped to 1M..end
|
||||
// KERNBASE+end..KERBASE+PHYSTOP : mapped to end..PHYSTOP (free memory)
|
||||
// 0xfe000000..0 : mapped direct (devices such as ioapic)
|
||||
//
|
||||
// The kernel allocates memory for its heap and for user memory
|
||||
// between kernend and the end of physical memory (PHYSTOP).
|
||||
// The virtual address space of each user program includes the kernel
|
||||
// (which is inaccessible in user mode). The user program addresses
|
||||
// range from 0 till 640KB (USERTOP), which where the I/O hole starts
|
||||
// (both in physical memory and in the kernel's virtual address
|
||||
// space).
|
||||
// (which is inaccessible in user mode). The user program sits in
|
||||
// the bottom of the address space, and the kernel at the top at KERNBASE.
|
||||
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.
|
||||
|
|
@ -142,12 +194,21 @@ 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;
|
||||
}
|
||||
|
||||
// Allocate one page table for the machine for the kernel address
|
||||
// space for scheduler processes.
|
||||
void
|
||||
kvmalloc(void)
|
||||
{
|
||||
kpgdir = setupkvm();
|
||||
switchkvm();
|
||||
}
|
||||
|
||||
// Turn on paging.
|
||||
void
|
||||
vmenable(void)
|
||||
|
|
@ -158,6 +219,16 @@ vmenable(void)
|
|||
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,
|
||||
|
|
@ -165,7 +236,7 @@ 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.
|
||||
|
|
@ -180,7 +251,7 @@ switchuvm(struct proc *p)
|
|||
ltr(SEG_TSS << 3);
|
||||
if(p->pgdir == 0)
|
||||
panic("switchuvm: no pgdir");
|
||||
lcr3(PADDR(p->pgdir)); // switch to new address space
|
||||
lcr3(v2p(p->pgdir)); // switch to new address space
|
||||
popcli();
|
||||
}
|
||||
|
||||
|
|
@ -195,7 +266,7 @@ inituvm(pde_t *pgdir, char *init, uint sz)
|
|||
panic("inituvm: more than a page");
|
||||
mem = kalloc();
|
||||
memset(mem, 0, PGSIZE);
|
||||
mappages(pgdir, 0, PGSIZE, PADDR(mem), PTE_W|PTE_U);
|
||||
mappages(pgdir, 0, PGSIZE, v2p(mem), PTE_W|PTE_U);
|
||||
memmove(mem, init, sz);
|
||||
}
|
||||
|
||||
|
|
@ -245,7 +316,7 @@ allocuvm(pde_t *pgdir, uint oldsz, uint newsz)
|
|||
return 0;
|
||||
}
|
||||
memset(mem, 0, PGSIZE);
|
||||
mappages(pgdir, (char*)a, PGSIZE, PADDR(mem), PTE_W|PTE_U);
|
||||
mappages(pgdir, (char*)a, PGSIZE, v2p(mem), PTE_W|PTE_U);
|
||||
}
|
||||
return newsz;
|
||||
}
|
||||
|
|
@ -289,7 +360,7 @@ freevm(pde_t *pgdir)
|
|||
deallocuvm(pgdir, USERTOP, 0);
|
||||
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);
|
||||
}
|
||||
|
|
@ -315,7 +386,7 @@ copyuvm(pde_t *pgdir, uint sz)
|
|||
if((mem = kalloc()) == 0)
|
||||
goto bad;
|
||||
memmove(mem, (char*)pa, PGSIZE);
|
||||
if(mappages(d, (void*)i, PGSIZE, PADDR(mem), PTE_W|PTE_U) < 0)
|
||||
if(mappages(d, (void*)i, PGSIZE, v2p(mem), PTE_W|PTE_U) < 0)
|
||||
goto bad;
|
||||
}
|
||||
return d;
|
||||
|
|
|
|||
24
x86.h
24
x86.h
|
|
@ -96,6 +96,30 @@ 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)
|
||||
{
|
||||
|
|
|
|||
Loading…
Reference in a new issue