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xv6-public
提交 9acdfe0d 创建 作者: Frans Kaashoek's avatar Frans Kaashoek
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Merge branch 'page' of git+ssh://amsterdam.csail.mit.edu/home/am0/6.828/xv6 into page

上级 791d81ca 7d7dc933
隐藏空白字符变更
内嵌 并排
正在显示 包含 46 行增加 和 91 行删除
defs.h
浏览文件 @ 9acdfe0d
......@@ -60,9 +60,8 @@ extern uchar ioapicid;
void ioapicinit(void);
// kalloc.c
extern int nfreemem;
char* kalloc(int);
void kfree(char*, int);
char* kalloc(void);
void kfree(char*);
void kinit(char*,uint);
// kbd.c
......
kalloc.c
浏览文件 @ 9acdfe0d
// Physical memory allocator, intended to allocate
// memory for user processes. Allocates in 4096-byte pages.
// Free list is kept sorted and combines adjacent pages into
// long runs, to make it easier to allocate big segments.
// This combining is not useful now that xv6 uses paging.
// memory for user processes, kernel stacks, page table pages,
// and pipe buffers. Allocates 4096-byte pages.
#include "types.h"
#include "defs.h"
......@@ -12,7 +10,6 @@
struct run {
struct run *next;
int len; // bytes
};
struct {
......@@ -20,92 +17,52 @@ struct {
struct run *freelist;
} kmem;
int nfreemem;
// Initialize free list of physical pages.
void
kinit(char *p, uint len)
{
initlock(&kmem.lock, "kmem");
nfreemem = 0;
kfree(p, len);
char *p1 = (char*)PGROUNDUP((uint)p);
char *p2 = PGROUNDDOWN(p + len);
for( ; p1 < p2; p1 += 4096)
kfree(p1);
}
// Free the len bytes of memory pointed at by v,
// Free the page of physical memory pointed at by v,
// which normally should have been returned by a
// call to kalloc(len). (The exception is when
// call to kalloc(). (The exception is when
// initializing the allocator; see kinit above.)
void
kfree(char *v, int len)
kfree(char *v)
{
struct run *r, *rend, **rp, *p, *pend;
struct run *r;
if(len <= 0 || len % PGSIZE)
if(((uint) v) % PGSIZE || (uint)v < 1024*1024 || (uint)v >= PHYSTOP)
panic("kfree");
// Fill with junk to catch dangling refs.
memset(v, 1, len);
memset(v, 1, PGSIZE);
acquire(&kmem.lock);
nfreemem += len;
p = (struct run*)v;
pend = (struct run*)(v + len);
for(rp=&kmem.freelist; (r=*rp) != 0 && r <= pend; rp=&r->next){
rend = (struct run*)((char*)r + r->len);
if(r <= p && p < rend) {
cprintf("freeing a free page: r = 0x%x p = 0x%x rend = 0x%x\n",
r, p, rend);
panic("freeing free page");
}
if(rend == p){ // r before p: expand r to include p
r->len += len;
if(r->next && r->next == pend){ // r now next to r->next?
r->len += r->next->len;
r->next = r->next->next;
}
goto out;
}
if(pend == r){ // p before r: expand p to include, replace r
p->len = len + r->len;
p->next = r->next;
*rp = p;
goto out;
}
}
// Insert p before r in list.
p->len = len;
p->next = r;
*rp = p;
out:
r = (struct run *) v;
r->next = kmem.freelist;
kmem.freelist = r;
release(&kmem.lock);
}
// Allocate n bytes of physical memory.
// Returns a kernel-segment pointer.
// Allocate one 4096-byte page of physical memory.
// Returns a pointer that the kernel can use.
// Returns 0 if the memory cannot be allocated.
char*
kalloc(int n)
kalloc()
{
char *p;
struct run *r, **rp;
if(n % PGSIZE || n <= 0)
panic("kalloc");
struct run *r;
acquire(&kmem.lock);
for(rp=&kmem.freelist; (r=*rp) != 0; rp=&r->next){
if(r->len >= n){
r->len -= n;
p = (char*)r + r->len;
if(r->len == 0)
*rp = r->next;
nfreemem -= n;
release(&kmem.lock);
return p;
}
}
r = kmem.freelist;
if(r)
kmem.freelist = r->next;
release(&kmem.lock);
return 0;
return (char*) r;
}
main.c
浏览文件 @ 9acdfe0d
......@@ -28,7 +28,7 @@ main(void)
void
jkstack(void)
{
char *kstack = kalloc(PGSIZE);
char *kstack = kalloc();
if (!kstack)
panic("jkstack\n");
char *top = kstack + PGSIZE;
......@@ -92,7 +92,7 @@ bootothers(void)
continue;
// Fill in %esp, %eip and start code on cpu.
stack = kalloc(KSTACKSIZE);
stack = kalloc();
*(void**)(code-4) = stack + KSTACKSIZE;
*(void**)(code-8) = mpmain;
lapicstartap(c->id, (uint)code);
......
mmu.h
浏览文件 @ 9acdfe0d
......@@ -112,7 +112,7 @@ struct segdesc {
#define PDXSHIFT 22 // offset of PDX in a linear address
#define PGROUNDUP(sz) (((sz)+PGSIZE-1) & ~(PGSIZE-1))
#define PGROUNDDOWN(a) ((char*)((((unsigned int)a) & ~(PGSIZE-1))))
#define PGROUNDDOWN(a) ((char*)((((unsigned int)(a)) & ~(PGSIZE-1))))
// Page table/directory entry flags.
#define PTE_P 0x001 // Present
......
param.h
浏览文件 @ 9acdfe0d
#define NPROC 64 // maximum number of processes
#define PAGE 4096 // conveniently chosen to be equal to PGSIZE
#define KSTACKSIZE PAGE // size of per-process kernel stack
#define KSTACKSIZE 4096 // size of per-process kernel stack
#define NCPU 8 // maximum number of CPUs
#define NOFILE 16 // open files per process
#define NFILE 100 // open files per system
......@@ -8,3 +7,4 @@
#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 PHYSTOP 0x1000000 // use phys mem up to here as free pool
pipe.c
浏览文件 @ 9acdfe0d
......@@ -27,7 +27,7 @@ pipealloc(struct file **f0, struct file **f1)
*f0 = *f1 = 0;
if((*f0 = filealloc()) == 0 || (*f1 = filealloc()) == 0)
goto bad;
if((p = (struct pipe*)kalloc(PAGE)) == 0)
if((p = (struct pipe*)kalloc()) == 0)
goto bad;
p->readopen = 1;
p->writeopen = 1;
......@@ -47,7 +47,7 @@ pipealloc(struct file **f0, struct file **f1)
//PAGEBREAK: 20
bad:
if(p)
kfree((char*)p, PAGE);
kfree((char*)p);
if(*f0)
fileclose(*f0);
if(*f1)
......@@ -68,7 +68,7 @@ pipeclose(struct pipe *p, int writable)
}
if(p->readopen == 0 && p->writeopen == 0) {
release(&p->lock);
kfree((char*)p, PAGE);
kfree((char*)p);
} else
release(&p->lock);
}
......
proc.c
浏览文件 @ 9acdfe0d
......@@ -84,7 +84,7 @@ found:
release(&ptable.lock);
// Allocate kernel stack if possible.
if((p->kstack = kalloc(KSTACKSIZE)) == 0){
if((p->kstack = kalloc()) == 0){
p->state = UNUSED;
return 0;
}
......@@ -169,7 +169,7 @@ fork(void)
// Copy process state from p.
if (!(np->pgdir = copyuvm(proc->pgdir, proc->sz))) {
kfree(np->kstack, KSTACKSIZE);
kfree(np->kstack);
np->kstack = 0;
np->state = UNUSED;
return -1;
......@@ -418,7 +418,7 @@ wait(void)
if(p->state == ZOMBIE){
// Found one.
pid = p->pid;
kfree(p->kstack, KSTACKSIZE);
kfree(p->kstack);
p->kstack = 0;
freevm(p->pgdir);
p->state = UNUSED;
......
umalloc.c
浏览文件 @ 9acdfe0d
......@@ -49,8 +49,8 @@ morecore(uint nu)
char *p;
Header *hp;
if(nu < PAGE)
nu = PAGE;
if(nu < 4096)
nu = 4096;
p = sbrk(nu * sizeof(Header));
if(p == (char*) -1)
return 0;
......
vm.c
浏览文件 @ 9acdfe0d
......@@ -29,7 +29,6 @@
// (both in physical memory and in the kernel's virtual address
// space).
#define PHYSTOP 0x1000000
#define USERTOP 0xA0000
static uint kerntext; // Linker starts kernel at 1MB
......@@ -53,7 +52,7 @@ walkpgdir(pde_t *pgdir, const void *va, int create)
pde = &pgdir[PDX(va)];
if (*pde & PTE_P) {
pgtab = (pte_t*) PTE_ADDR(*pde);
} else if (!create || !(r = (uint) kalloc(PGSIZE)))
} else if (!create || !(r = (uint) kalloc()))
return 0;
else {
pgtab = (pte_t*) r;
......@@ -156,7 +155,7 @@ setupkvm(void)
pde_t *pgdir;
// Allocate page directory
if (!(pgdir = (pde_t *) kalloc(PGSIZE)))
if (!(pgdir = (pde_t *) kalloc()))
return 0;
memset(pgdir, 0, PGSIZE);
// Map IO space from 640K to 1Mbyte
......@@ -206,7 +205,7 @@ allocuvm(pde_t *pgdir, char *addr, uint sz)
for(a = first; a <= last; a += PGSIZE){
pte_t *pte = walkpgdir(pgdir, a, 0);
if(pte == 0 || (*pte & PTE_P) == 0){
char *mem = kalloc(PGSIZE);
char *mem = kalloc();
if(mem == 0){
// XXX clean up?
return 0;
......@@ -235,7 +234,7 @@ deallocuvm(pde_t *pgdir, char *addr, uint sz)
uint pa = PTE_ADDR(*pte);
if(pa == 0)
panic("deallocuvm");
kfree((void *) pa, PGSIZE);
kfree((void *) pa);
*pte = 0;
}
}
......@@ -260,15 +259,15 @@ freevm(pde_t *pgdir)
uint pa = PTE_ADDR(pgtab[j]);
uint va = PGADDR(i, j, 0);
if (va < USERTOP) // user memory
kfree((void *) pa, PGSIZE);
kfree((void *) pa);
pgtab[j] = 0;
}
}
kfree((void *) da, PGSIZE);
kfree((void *) da);
pgdir[i] = 0;
}
}
kfree((void *) pgdir, PGSIZE);
kfree((void *) pgdir);
}
int
......@@ -324,7 +323,7 @@ copyuvm(pde_t *pgdir, uint sz)
panic("copyuvm: pte should exist\n");
if(*pte & PTE_P){
pa = PTE_ADDR(*pte);
if (!(mem = kalloc(PGSIZE)))
if (!(mem = kalloc()))
return 0;
memmove(mem, (char *)pa, PGSIZE);
if (!mappages(d, (void *)i, PGSIZE, PADDR(mem), PTE_W|PTE_U))
......
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