make new code like old code
Variable declarations at top of function,
separate from initialization.
Use == 0 instead of ! for checking pointers.
Consistent spacing around {, *, casts.
Declare 0-parameter functions as (void) not ().
Integer valued functions return -1 on failure, 0 on success.
This commit is contained in:
Russ Cox
parent
240679608c
commit
1a81e38b17
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@ -27,15 +27,16 @@ printint(int xx, int base, int sgn)
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{
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static char digits[] = "0123456789abcdef";
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char buf[16];
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int i = 0, neg = 0;
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int i, neg;
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uint x;
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if(sgn && xx < 0){
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if(sgn && (neg = xx < 0)){
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neg = 1;
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x = -xx;
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} else
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x = xx;
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i = 0;
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do{
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buf[i++] = digits[x % base];
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}while((x /= base) != 0);
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8
defs.h
8
defs.h
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@ -62,7 +62,7 @@ void ioapicinit(void);
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// kalloc.c
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char* kalloc(void);
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void kfree(char*);
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void kinit();
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void kinit(void);
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// kbd.c
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void kbdintr(void);
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@ -117,8 +117,8 @@ void getcallerpcs(void*, uint*);
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int holding(struct spinlock*);
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void initlock(struct spinlock*, char*);
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void release(struct spinlock*);
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void pushcli();
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void popcli();
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void pushcli(void);
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void popcli(void);
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// string.c
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int memcmp(const void*, const void*, uint);
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@ -164,7 +164,7 @@ void inituvm(pde_t*, char*, uint);
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int loaduvm(pde_t*, char*, struct inode *, uint, uint);
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pde_t* copyuvm(pde_t*,uint);
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void switchuvm(struct proc*);
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void switchkvm();
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void switchkvm(void);
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int copyout(pde_t *pgdir, uint va, void *buf, uint len);
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// number of elements in fixed-size array
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22
exec.c
22
exec.c
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@ -10,16 +10,17 @@ int
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exec(char *path, char **argv)
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{
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char *s, *last;
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int i, off;
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uint sz = 0;
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int i, off, argc;
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uint sz, sp, strings[MAXARG];
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struct elfhdr elf;
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struct inode *ip = 0;
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struct inode *ip;
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struct proghdr ph;
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pde_t *pgdir = 0, *oldpgdir;
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pde_t *pgdir, *oldpgdir;
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if((ip = namei(path)) == 0)
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return -1;
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ilock(ip);
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pgdir = 0;
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// Check ELF header
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if(readi(ip, (char*)&elf, 0, sizeof(elf)) < sizeof(elf))
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@ -27,10 +28,11 @@ exec(char *path, char **argv)
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if(elf.magic != ELF_MAGIC)
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goto bad;
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if(!(pgdir = setupkvm()))
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if((pgdir = setupkvm()) == 0)
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goto bad;
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// Load program into memory.
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sz = 0;
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for(i=0, off=elf.phoff; i<elf.phnum; i++, off+=sizeof(ph)){
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if(readi(ip, (char*)&ph, off, sizeof(ph)) != sizeof(ph))
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goto bad;
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@ -38,9 +40,9 @@ exec(char *path, char **argv)
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continue;
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if(ph.memsz < ph.filesz)
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goto bad;
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if(!(sz = allocuvm(pgdir, sz, ph.va + ph.memsz)))
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if((sz = allocuvm(pgdir, sz, ph.va + ph.memsz)) == 0)
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goto bad;
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if(!loaduvm(pgdir, (char *)ph.va, ip, ph.offset, ph.filesz))
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if(loaduvm(pgdir, (char*)ph.va, ip, ph.offset, ph.filesz) < 0)
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goto bad;
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}
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iunlockput(ip);
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@ -48,7 +50,7 @@ exec(char *path, char **argv)
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// Allocate a one-page stack at the next page boundary
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sz = PGROUNDUP(sz);
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if(!(sz = allocuvm(pgdir, sz, sz + PGSIZE)))
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if((sz = allocuvm(pgdir, sz, sz + PGSIZE)) == 0)
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goto bad;
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// initialize stack content:
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@ -64,17 +66,15 @@ exec(char *path, char **argv)
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// argc -- argc argument to main()
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// ffffffff -- return PC for main() call
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uint sp = sz;
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sp = sz;
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// count arguments
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int argc;
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for(argc = 0; argv[argc]; argc++)
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;
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if(argc >= MAXARG)
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goto bad;
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// push strings and remember where they are
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uint strings[MAXARG];
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for(i = argc - 1; i >= 0; --i){
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sp -= strlen(argv[i]) + 1;
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strings[i] = sp;
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2
ide.c
2
ide.c
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@ -131,7 +131,7 @@ iderw(struct buf *b)
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if((b->flags & (B_VALID|B_DIRTY)) == B_VALID)
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panic("iderw: nothing to do");
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if(b->dev != 0 && !havedisk1)
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panic("idrw: ide disk 1 not present");
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panic("iderw: ide disk 1 not present");
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acquire(&idelock);
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8
kalloc.c
8
kalloc.c
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@ -23,8 +23,10 @@ extern char end[]; // first address after kernel loaded from ELF file
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void
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kinit(void)
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{
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char *p;
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initlock(&kmem.lock, "kmem");
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char *p = (char*)PGROUNDUP((uint)end);
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p = (char*)PGROUNDUP((uint)end);
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for(; p + PGSIZE - 1 < (char*)PHYSTOP; p += PGSIZE)
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kfree(p);
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}
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@ -39,7 +41,7 @@ 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 || (uint)v >= PHYSTOP)
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panic("kfree");
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// Fill with junk to catch dangling refs.
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@ -56,7 +58,7 @@ kfree(char *v)
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// Returns a pointer that the kernel can use.
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// Returns 0 if the memory cannot be allocated.
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char*
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kalloc()
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kalloc(void)
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{
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struct run *r;
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26
main.c
26
main.c
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@ -7,7 +7,7 @@
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static void bootothers(void);
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static void mpmain(void);
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void jkstack(void) __attribute__((noreturn));
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void jmpkstack(void) __attribute__((noreturn));
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void mainc(void);
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// Bootstrap processor starts running C code here.
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@ -20,19 +20,20 @@ main(void)
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lapicinit(mpbcpu());
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seginit(); // set up segments
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kinit(); // initialize memory allocator
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jkstack(); // call mainc() on a properly-allocated stack
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jmpkstack(); // call mainc() on a properly-allocated stack
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}
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void
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jkstack(void)
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jmpkstack(void)
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{
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char *kstack = kalloc();
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if(!kstack)
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panic("jkstack\n");
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char *top = kstack + PGSIZE;
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asm volatile("movl %0,%%esp" : : "r" (top));
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asm volatile("call mainc");
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panic("jkstack");
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char *kstack, *top;
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kstack = kalloc();
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if(kstack == 0)
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panic("jmpkstack kalloc");
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top = kstack + PGSIZE;
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asm volatile("movl %0,%%esp; call mainc" : : "r" (top));
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panic("jmpkstack");
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}
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// Set up hardware and software.
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@ -87,8 +88,8 @@ bootothers(void)
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struct cpu *c;
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char *stack;
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// Write bootstrap code to unused memory at 0x7000. The linker has
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// placed the start of bootother.S there.
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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 _binary_bootother_start.
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code = (uchar*)0x7000;
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memmove(code, _binary_bootother_start, (uint)_binary_bootother_size);
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@ -110,4 +111,3 @@ bootothers(void)
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;
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}
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}
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6
mmu.h
6
mmu.h
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@ -98,10 +98,10 @@ struct segdesc {
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// \--- PDX(la) --/ \--- PTX(la) --/
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// page directory index
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#define PDX(la) ((((uint) (la)) >> PDXSHIFT) & 0x3FF)
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#define PDX(la) (((uint)(la) >> PDXSHIFT) & 0x3FF)
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// page table index
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#define PTX(la) ((((uint) (la)) >> PTXSHIFT) & 0x3FF)
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#define PTX(la) (((uint)(la) >> PTXSHIFT) & 0x3FF)
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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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#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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2
mp.c
2
mp.c
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@ -114,7 +114,7 @@ mpinit(void)
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case MPPROC:
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proc = (struct mpproc*)p;
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if(ncpu != proc->apicid){
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cprintf("mpinit: ncpu=%d apicpid=%d", ncpu, proc->apicid);
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cprintf("mpinit: ncpu=%d apicpid=%d\n", ncpu, proc->apicid);
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panic("mpinit");
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}
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if(proc->flags & MPBOOT)
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12
proc.c
12
proc.c
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@ -120,7 +120,7 @@ userinit(void)
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p = allocproc();
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initproc = p;
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if(!(p->pgdir = setupkvm()))
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if((p->pgdir = setupkvm()) == 0)
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panic("userinit: out of memory?");
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inituvm(p->pgdir, _binary_initcode_start, (int)_binary_initcode_size);
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p->sz = PGSIZE;
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@ -144,12 +144,14 @@ userinit(void)
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int
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growproc(int n)
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{
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uint sz = proc->sz;
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uint sz;
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sz = proc->sz;
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if(n > 0){
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if(!(sz = allocuvm(proc->pgdir, sz, sz + n)))
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if((sz = allocuvm(proc->pgdir, sz, sz + n)) == 0)
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return -1;
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} else if(n < 0){
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if(!(sz = deallocuvm(proc->pgdir, sz, sz + n)))
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if((sz = deallocuvm(proc->pgdir, sz, sz + n)) == 0)
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return -1;
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}
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proc->sz = sz;
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@ -171,7 +173,7 @@ fork(void)
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return -1;
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// Copy process state from p.
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if(!(np->pgdir = copyuvm(proc->pgdir, proc->sz))){
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if((np->pgdir = copyuvm(proc->pgdir, proc->sz)) == 0){
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kfree(np->kstack);
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np->kstack = 0;
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np->state = UNUSED;
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13
stressfs.c
13
stressfs.c
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@ -14,20 +14,19 @@
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int
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main(int argc, char *argv[])
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{
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int i;
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int fd, i;
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char path[] = "stressfs0";
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printf(1, "stressfs starting\n");
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for(i = 0; i < 4; i++){
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if(fork() > 0){
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for(i = 0; i < 4; i++)
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if(fork() > 0)
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break;
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}
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}
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printf(1, "%d\n", i);
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char path[] = "stressfs0";
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path[8] += i;
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int fd = open(path, O_CREATE | O_RDWR);
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fd = open(path, O_CREATE | O_RDWR);
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for(i = 0; i < 100; i++)
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printf(fd, "%d\n", i);
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close(fd);
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|
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@ -44,8 +44,7 @@ fetchstr(struct proc *p, uint addr, char **pp)
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int
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argint(int n, int *ip)
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{
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int x = fetchint(proc, proc->tf->esp + 4 + 4*n, ip);
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return x;
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return fetchint(proc, proc->tf->esp + 4 + 4*n, ip);
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}
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// Fetch the nth word-sized system call argument as a pointer
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|
|
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4
user.h
4
user.h
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@ -18,10 +18,10 @@ int link(char*, char*);
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int mkdir(char*);
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int chdir(char*);
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int dup(int);
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int getpid();
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int getpid(void);
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char* sbrk(int);
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int sleep(int);
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int uptime();
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int uptime(void);
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// ulib.c
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int stat(char*, struct stat*);
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|
|
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32
usertests.c
32
usertests.c
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|
@ -1237,16 +1237,18 @@ forktest(void)
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void
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sbrktest(void)
|
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{
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int pid;
|
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char *oldbrk = sbrk(0);
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int fds[2], pid, pids[32], ppid;
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char *a, *b, *c, *lastaddr, *oldbrk, *p, scratch;
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uint amt;
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|
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printf(stdout, "sbrk test\n");
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oldbrk = sbrk(0);
|
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|
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// can one sbrk() less than a page?
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char *a = sbrk(0);
|
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a = sbrk(0);
|
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int i;
|
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for(i = 0; i < 5000; i++){
|
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char *b = sbrk(1);
|
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b = sbrk(1);
|
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if(b != a){
|
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printf(stdout, "sbrk test failed %d %x %x\n", i, a, b);
|
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exit();
|
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|
|
@ -1259,7 +1261,7 @@ sbrktest(void)
|
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printf(stdout, "sbrk test fork failed\n");
|
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exit();
|
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}
|
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char *c = sbrk(1);
|
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c = sbrk(1);
|
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c = sbrk(1);
|
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if(c != a + 1){
|
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printf(stdout, "sbrk test failed post-fork\n");
|
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|
|
@ -1271,13 +1273,13 @@ sbrktest(void)
|
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|
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// can one allocate the full 640K?
|
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a = sbrk(0);
|
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uint amt = (640 * 1024) - (uint) a;
|
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char *p = sbrk(amt);
|
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amt = (640 * 1024) - (uint)a;
|
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p = sbrk(amt);
|
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if(p != a){
|
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printf(stdout, "sbrk test failed 640K test, p %x a %x\n", p, a);
|
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exit();
|
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}
|
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char *lastaddr = (char *)(640 * 1024 - 1);
|
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lastaddr = (char*)(640 * 1024 - 1);
|
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*lastaddr = 99;
|
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|
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// is one forbidden from allocating more than 640K?
|
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|
|
@ -1321,8 +1323,8 @@ sbrktest(void)
|
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|
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// can we read the kernel's memory?
|
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for(a = (char*)(640*1024); a < (char*)2000000; a += 50000){
|
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int ppid = getpid();
|
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int pid = fork();
|
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ppid = getpid();
|
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pid = fork();
|
||||
if(pid < 0){
|
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printf(stdout, "fork failed\n");
|
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exit();
|
||||
|
|
@ -1338,8 +1340,6 @@ sbrktest(void)
|
|||
// if we run the system out of memory, does it clean up the last
|
||||
// failed allocation?
|
||||
sbrk(-(sbrk(0) - oldbrk));
|
||||
int pids[32];
|
||||
int fds[2];
|
||||
if(pipe(fds) != 0){
|
||||
printf(1, "pipe() failed\n");
|
||||
exit();
|
||||
|
|
@ -1352,7 +1352,6 @@ sbrktest(void)
|
|||
// sit around until killed
|
||||
for(;;) sleep(1000);
|
||||
}
|
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char scratch;
|
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if(pids[i] != -1)
|
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read(fds[0], &scratch, 1);
|
||||
}
|
||||
|
|
@ -1392,13 +1391,13 @@ validateint(int *p)
|
|||
void
|
||||
validatetest(void)
|
||||
{
|
||||
int hi = 1100*1024;
|
||||
int hi, pid;
|
||||
uint p;
|
||||
|
||||
printf(stdout, "validate test\n");
|
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hi = 1100*1024;
|
||||
|
||||
uint p;
|
||||
for(p = 0; p <= (uint)hi; p += 4096){
|
||||
int pid;
|
||||
if((pid = fork()) == 0){
|
||||
// try to crash the kernel by passing in a badly placed integer
|
||||
validateint((int*)p);
|
||||
|
|
@ -1425,6 +1424,7 @@ void
|
|||
bsstest(void)
|
||||
{
|
||||
int i;
|
||||
|
||||
printf(stdout, "bss test\n");
|
||||
for(i = 0; i < sizeof(uninit); i++){
|
||||
if(uninit[i] != '\0'){
|
||||
|
|
|
|||
129
vm.c
129
vm.c
|
|
@ -42,23 +42,21 @@ seginit(void)
|
|||
static pte_t *
|
||||
walkpgdir(pde_t *pgdir, const void *va, int create)
|
||||
{
|
||||
uint r;
|
||||
pde_t *pde;
|
||||
pte_t *pgtab;
|
||||
|
||||
pde = &pgdir[PDX(va)];
|
||||
if(*pde & PTE_P){
|
||||
pgtab = (pte_t*)PTE_ADDR(*pde);
|
||||
} else if(!create || !(r = (uint) kalloc()))
|
||||
} else {
|
||||
if(!create || (pgtab = (pte_t*)kalloc()) == 0)
|
||||
return 0;
|
||||
else {
|
||||
pgtab = (pte_t*) r;
|
||||
// Make sure all those PTE_P bits are zero.
|
||||
memset(pgtab, 0, PGSIZE);
|
||||
// The permissions here are overly generous, but they can
|
||||
// be further restricted by the permissions in the page table
|
||||
// entries, if necessary.
|
||||
*pde = PADDR(r) | PTE_P | PTE_W | PTE_U;
|
||||
*pde = PADDR(pgtab) | PTE_P | PTE_W | PTE_U;
|
||||
}
|
||||
return &pgtab[PTX(va)];
|
||||
}
|
||||
|
|
@ -69,13 +67,16 @@ walkpgdir(pde_t *pgdir, const void *va, int create)
|
|||
static int
|
||||
mappages(pde_t *pgdir, void *la, uint size, uint pa, int perm)
|
||||
{
|
||||
char *a = PGROUNDDOWN(la);
|
||||
char *last = PGROUNDDOWN(la + size - 1);
|
||||
char *a, *last;
|
||||
pte_t *pte;
|
||||
|
||||
while(1){
|
||||
pte_t *pte = walkpgdir(pgdir, a, 1);
|
||||
a = PGROUNDDOWN(la);
|
||||
last = PGROUNDDOWN(la + size - 1);
|
||||
|
||||
for(;;){
|
||||
pte = walkpgdir(pgdir, a, 1);
|
||||
if(pte == 0)
|
||||
return 0;
|
||||
return -1;
|
||||
if(*pte & PTE_P)
|
||||
panic("remap");
|
||||
*pte = pa | perm | PTE_P;
|
||||
|
|
@ -84,7 +85,7 @@ mappages(pde_t *pgdir, void *la, uint size, uint pa, int perm)
|
|||
a += PGSIZE;
|
||||
pa += PGSIZE;
|
||||
}
|
||||
return 1;
|
||||
return 0;
|
||||
}
|
||||
|
||||
// The mappings from logical to linear are one to one (i.e.,
|
||||
|
|
@ -122,23 +123,26 @@ kvmalloc(void)
|
|||
pde_t*
|
||||
setupkvm(void)
|
||||
{
|
||||
pde_t *pgdir;
|
||||
extern char etext[];
|
||||
char *rwstart = PGROUNDDOWN(etext);
|
||||
uint rwlen = (uint)rwstart - 0x100000;
|
||||
char *rwstart;
|
||||
pde_t *pgdir;
|
||||
uint rwlen;
|
||||
|
||||
rwstart = PGROUNDDOWN(etext);
|
||||
rwlen = (uint)rwstart - 0x100000;
|
||||
|
||||
// Allocate page directory
|
||||
if(!(pgdir = (pde_t *) kalloc()))
|
||||
if((pgdir = (pde_t*)kalloc()) == 0)
|
||||
return 0;
|
||||
memset(pgdir, 0, PGSIZE);
|
||||
if(// Map IO space from 640K to 1Mbyte
|
||||
!mappages(pgdir, (void *)USERTOP, 0x60000, USERTOP, PTE_W) ||
|
||||
mappages(pgdir, (void*)USERTOP, 0x60000, USERTOP, PTE_W) < 0 ||
|
||||
// Map kernel instructions
|
||||
!mappages(pgdir, (void *)0x100000, rwlen, 0x100000, 0) ||
|
||||
mappages(pgdir, (void*)0x100000, rwlen, 0x100000, 0) < 0 ||
|
||||
// Map kernel data and free memory pool
|
||||
!mappages(pgdir, rwstart, PHYSTOP-(uint)rwstart, (uint)rwstart, PTE_W) ||
|
||||
mappages(pgdir, rwstart, PHYSTOP-(uint)rwstart, (uint)rwstart, PTE_W) < 0 ||
|
||||
// Map devices such as ioapic, lapic, ...
|
||||
!mappages(pgdir, (void *)0xFE000000, 0x2000000, 0xFE000000, PTE_W))
|
||||
mappages(pgdir, (void*)0xFE000000, 0x2000000, 0xFE000000, PTE_W) < 0)
|
||||
return 0;
|
||||
return pgdir;
|
||||
}
|
||||
|
|
@ -190,13 +194,14 @@ switchuvm(struct proc *p)
|
|||
char*
|
||||
uva2ka(pde_t *pgdir, char *uva)
|
||||
{
|
||||
pte_t *pte = walkpgdir(pgdir, uva, 0);
|
||||
pte_t *pte;
|
||||
|
||||
pte = walkpgdir(pgdir, uva, 0);
|
||||
if((*pte & PTE_P) == 0)
|
||||
return 0;
|
||||
if((*pte & PTE_U) == 0)
|
||||
return 0;
|
||||
uint pa = PTE_ADDR(*pte);
|
||||
return (char *)pa;
|
||||
return (char*)PTE_ADDR(*pte);
|
||||
}
|
||||
|
||||
// Load the initcode into address 0 of pgdir.
|
||||
|
|
@ -204,9 +209,11 @@ uva2ka(pde_t *pgdir, char *uva)
|
|||
void
|
||||
inituvm(pde_t *pgdir, char *init, uint sz)
|
||||
{
|
||||
char *mem = kalloc();
|
||||
char *mem;
|
||||
|
||||
if(sz >= PGSIZE)
|
||||
panic("inituvm: more than a page");
|
||||
mem = kalloc();
|
||||
memset(mem, 0, PGSIZE);
|
||||
mappages(pgdir, 0, PGSIZE, PADDR(mem), PTE_W|PTE_U);
|
||||
memmove(mem, init, sz);
|
||||
|
|
@ -223,15 +230,17 @@ loaduvm(pde_t *pgdir, char *addr, struct inode *ip, uint offset, uint sz)
|
|||
if((uint)addr % PGSIZE != 0)
|
||||
panic("loaduvm: addr must be page aligned\n");
|
||||
for(i = 0; i < sz; i += PGSIZE){
|
||||
if(!(pte = walkpgdir(pgdir, addr+i, 0)))
|
||||
if((pte = walkpgdir(pgdir, addr+i, 0)) == 0)
|
||||
panic("loaduvm: address should exist\n");
|
||||
pa = PTE_ADDR(*pte);
|
||||
if(sz - i < PGSIZE) n = sz - i;
|
||||
else n = PGSIZE;
|
||||
if(sz - i < PGSIZE)
|
||||
n = sz - i;
|
||||
else
|
||||
n = PGSIZE;
|
||||
if(readi(ip, (char*)pa, offset+i, n) != n)
|
||||
return 0;
|
||||
return -1;
|
||||
}
|
||||
return 1;
|
||||
return 0;
|
||||
}
|
||||
|
||||
// Allocate memory to the process to bring its size from oldsz to
|
||||
|
|
@ -241,12 +250,17 @@ loaduvm(pde_t *pgdir, char *addr, struct inode *ip, uint offset, uint sz)
|
|||
int
|
||||
allocuvm(pde_t *pgdir, uint oldsz, uint newsz)
|
||||
{
|
||||
char *a, *last, *mem;
|
||||
|
||||
if(newsz > USERTOP)
|
||||
return 0;
|
||||
char *a = (char *)PGROUNDUP(oldsz);
|
||||
char *last = PGROUNDDOWN(newsz - 1);
|
||||
if(newsz < oldsz)
|
||||
return oldsz;
|
||||
|
||||
a = (char*)PGROUNDUP(oldsz);
|
||||
last = PGROUNDDOWN(newsz - 1);
|
||||
for(; a <= last; a += PGSIZE){
|
||||
char *mem = kalloc();
|
||||
mem = kalloc();
|
||||
if(mem == 0){
|
||||
cprintf("allocuvm out of memory\n");
|
||||
deallocuvm(pgdir, newsz, oldsz);
|
||||
|
|
@ -255,7 +269,7 @@ allocuvm(pde_t *pgdir, uint oldsz, uint newsz)
|
|||
memset(mem, 0, PGSIZE);
|
||||
mappages(pgdir, a, PGSIZE, PADDR(mem), PTE_W|PTE_U);
|
||||
}
|
||||
return newsz > oldsz ? newsz : oldsz;
|
||||
return newsz;
|
||||
}
|
||||
|
||||
// Deallocate user pages to bring the process size from oldsz to
|
||||
|
|
@ -265,19 +279,26 @@ allocuvm(pde_t *pgdir, uint oldsz, uint newsz)
|
|||
int
|
||||
deallocuvm(pde_t *pgdir, uint oldsz, uint newsz)
|
||||
{
|
||||
char *a = (char *)PGROUNDUP(newsz);
|
||||
char *last = PGROUNDDOWN(oldsz - 1);
|
||||
char *a, *last;
|
||||
pte_t *pte;
|
||||
uint pa;
|
||||
|
||||
if(newsz >= oldsz)
|
||||
return oldsz;
|
||||
|
||||
a = (char*)PGROUNDUP(newsz);
|
||||
last = PGROUNDDOWN(oldsz - 1);
|
||||
for(; a <= last; a += PGSIZE){
|
||||
pte_t *pte = walkpgdir(pgdir, a, 0);
|
||||
pte = walkpgdir(pgdir, a, 0);
|
||||
if(pte && (*pte & PTE_P) != 0){
|
||||
uint pa = PTE_ADDR(*pte);
|
||||
pa = PTE_ADDR(*pte);
|
||||
if(pa == 0)
|
||||
panic("kfree");
|
||||
kfree((void *) pa);
|
||||
kfree((char*)pa);
|
||||
*pte = 0;
|
||||
}
|
||||
}
|
||||
return newsz < oldsz ? newsz : oldsz;
|
||||
return newsz;
|
||||
}
|
||||
|
||||
// Free a page table and all the physical memory pages
|
||||
|
|
@ -287,14 +308,14 @@ freevm(pde_t *pgdir)
|
|||
{
|
||||
uint i;
|
||||
|
||||
if(!pgdir)
|
||||
if(pgdir == 0)
|
||||
panic("freevm: no pgdir");
|
||||
deallocuvm(pgdir, USERTOP, 0);
|
||||
for(i = 0; i < NPDENTRIES; i++){
|
||||
if(pgdir[i] & PTE_P)
|
||||
kfree((void *) PTE_ADDR(pgdir[i]));
|
||||
kfree((char*)PTE_ADDR(pgdir[i]));
|
||||
}
|
||||
kfree((void *) pgdir);
|
||||
kfree((char*)pgdir);
|
||||
}
|
||||
|
||||
// Given a parent process's page table, create a copy
|
||||
|
|
@ -302,22 +323,23 @@ freevm(pde_t *pgdir)
|
|||
pde_t*
|
||||
copyuvm(pde_t *pgdir, uint sz)
|
||||
{
|
||||
pde_t *d = setupkvm();
|
||||
pde_t *d;
|
||||
pte_t *pte;
|
||||
uint pa, i;
|
||||
char *mem;
|
||||
|
||||
if(!d) return 0;
|
||||
if((d = setupkvm()) == 0)
|
||||
return 0;
|
||||
for(i = 0; i < sz; i += PGSIZE){
|
||||
if(!(pte = walkpgdir(pgdir, (void *)i, 0)))
|
||||
if((pte = walkpgdir(pgdir, (void*)i, 0)) == 0)
|
||||
panic("copyuvm: pte should exist\n");
|
||||
if(!(*pte & PTE_P))
|
||||
panic("copyuvm: page not present\n");
|
||||
pa = PTE_ADDR(*pte);
|
||||
if(!(mem = kalloc()))
|
||||
if((mem = kalloc()) == 0)
|
||||
goto bad;
|
||||
memmove(mem, (char*)pa, PGSIZE);
|
||||
if(!mappages(d, (void *)i, PGSIZE, PADDR(mem), PTE_W|PTE_U))
|
||||
if(mappages(d, (void*)i, PGSIZE, PADDR(mem), PTE_W|PTE_U) < 0)
|
||||
goto bad;
|
||||
}
|
||||
return d;
|
||||
|
|
@ -334,13 +356,16 @@ bad:
|
|||
int
|
||||
copyout(pde_t *pgdir, uint va, void *xbuf, uint len)
|
||||
{
|
||||
char *buf = (char *) xbuf;
|
||||
char *buf, *pa0;
|
||||
uint n, va0;
|
||||
|
||||
buf = (char*)xbuf;
|
||||
while(len > 0){
|
||||
uint va0 = (uint)PGROUNDDOWN(va);
|
||||
char *pa0 = uva2ka(pgdir, (char*) va0);
|
||||
va0 = (uint)PGROUNDDOWN(va);
|
||||
pa0 = uva2ka(pgdir, (char*)va0);
|
||||
if(pa0 == 0)
|
||||
return 0;
|
||||
uint n = PGSIZE - (va - va0);
|
||||
return -1;
|
||||
n = PGSIZE - (va - va0);
|
||||
if(n > len)
|
||||
n = len;
|
||||
memmove(pa0 + (va - va0), buf, n);
|
||||
|
|
@ -348,5 +373,5 @@ copyout(pde_t *pgdir, uint va, void *xbuf, uint len)
|
|||
buf += n;
|
||||
va = va0 + PGSIZE;
|
||||
}
|
||||
return 1;
|
||||
return 0;
|
||||
}
|
||||
|
|
|
|||
Loading…
Reference in a new issue