Imbus/xv6-riscv-kernel
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Imbus 2024-06-15 16:55:06 +02:00
parent b1a34398e9
commit d6793bf093
60 changed files with 1952 additions and 1995 deletions
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23
kernel/bio.c
View file

@ -13,7 +13,6 @@
// * Only one process at a time can use a buffer, // * Only one process at a time can use a buffer,
// so do not keep them longer than necessary. // so do not keep them longer than necessary.
#include "types.h" #include "types.h"
#include "param.h" #include "param.h"
#include "spinlock.h" #include "spinlock.h"
@ -43,7 +42,7 @@ binit(void)
// Create linked list of buffers // Create linked list of buffers
bcache.head.prev = &bcache.head; bcache.head.prev = &bcache.head;
bcache.head.next = &bcache.head; bcache.head.next = &bcache.head;
for(b = bcache.buf; b < bcache.buf+NBUF; b++){ for(b = bcache.buf; b < bcache.buf + NBUF; b++) {
b->next = bcache.head.next; b->next = bcache.head.next;
b->prev = &bcache.head; b->prev = &bcache.head;
initsleeplock(&b->lock, "buffer"); initsleeplock(&b->lock, "buffer");
@ -55,7 +54,7 @@ binit(void)
// Look through buffer cache for block on device dev. // Look through buffer cache for block on device dev.
// If not found, allocate a buffer. // If not found, allocate a buffer.
// In either case, return locked buffer. // In either case, return locked buffer.
static struct buf* static struct buf *
bget(u32 dev, u32 blockno) bget(u32 dev, u32 blockno)
{ {
struct buf *b; struct buf *b;
@ -63,8 +62,8 @@ bget(u32 dev, u32 blockno)
acquire(&bcache.lock); acquire(&bcache.lock);
// Is the block already cached? // Is the block already cached?
for(b = bcache.head.next; b != &bcache.head; b = b->next){ for(b = bcache.head.next; b != &bcache.head; b = b->next) {
if(b->dev == dev && b->blockno == blockno){ if(b->dev == dev && b->blockno == blockno) {
b->refcnt++; b->refcnt++;
release(&bcache.lock); release(&bcache.lock);
acquiresleep(&b->lock); acquiresleep(&b->lock);
@ -74,7 +73,7 @@ bget(u32 dev, u32 blockno)
// Not cached. // Not cached.
// Recycle the least recently used (LRU) unused buffer. // Recycle the least recently used (LRU) unused buffer.
for(b = bcache.head.prev; b != &bcache.head; b = b->prev){ for(b = bcache.head.prev; b != &bcache.head; b = b->prev) {
if(b->refcnt == 0) { if(b->refcnt == 0) {
b->dev = dev; b->dev = dev;
b->blockno = blockno; b->blockno = blockno;
@ -89,7 +88,7 @@ bget(u32 dev, u32 blockno)
} }
// Return a locked buf with the contents of the indicated block. // Return a locked buf with the contents of the indicated block.
struct buf* struct buf *
bread(u32 dev, u32 blockno) bread(u32 dev, u32 blockno)
{ {
struct buf *b; struct buf *b;
@ -123,7 +122,7 @@ brelse(struct buf *b)
acquire(&bcache.lock); acquire(&bcache.lock);
b->refcnt--; b->refcnt--;
if (b->refcnt == 0) { if(b->refcnt == 0) {
// no one is waiting for it. // no one is waiting for it.
b->next->prev = b->prev; b->next->prev = b->prev;
b->prev->next = b->next; b->prev->next = b->next;
@ -137,17 +136,17 @@ brelse(struct buf *b)
} }
void void
bpin(struct buf *b) { bpin(struct buf *b)
{
acquire(&bcache.lock); acquire(&bcache.lock);
b->refcnt++; b->refcnt++;
release(&bcache.lock); release(&bcache.lock);
} }
void void
bunpin(struct buf *b) { bunpin(struct buf *b)
{
acquire(&bcache.lock); acquire(&bcache.lock);
b->refcnt--; b->refcnt--;
release(&bcache.lock); release(&bcache.lock);
} }

1
kernel/buf.h
View file

@ -9,4 +9,3 @@ struct buf {
struct buf *next; struct buf *next;
u8 data[BSIZE]; u8 data[BSIZE];
}; };

35
kernel/console.c
View file

@ -23,7 +23,7 @@
#include "proc.h" #include "proc.h"
#define BACKSPACE 0x100 #define BACKSPACE 0x100
#define C(x) ((x)-'@') // Control-x #define C(x) ((x) - '@') // Control-x
// //
// send one character to the uart. // send one character to the uart.
@ -33,9 +33,11 @@
void void
consputc(int c) consputc(int c)
{ {
if(c == BACKSPACE){ if(c == BACKSPACE) {
// if the user typed backspace, overwrite with a space. // if the user typed backspace, overwrite with a space.
uartputc_sync('\b'); uartputc_sync(' '); uartputc_sync('\b'); uartputc_sync('\b');
uartputc_sync(' ');
uartputc_sync('\b');
} else { } else {
uartputc_sync(c); uartputc_sync(c);
} }
@ -60,9 +62,9 @@ consolewrite(int user_src, u64 src, int n)
{ {
int i; int i;
for(i = 0; i < n; i++){ for(i = 0; i < n; i++) {
char c; char c;
if(either_copyin(&c, user_src, src+i, 1) == -1) if(either_copyin(&c, user_src, src + i, 1) == -1)
break; break;
uartputc(c); uartputc(c);
} }
@ -85,11 +87,11 @@ consoleread(int user_dst, u64 dst, int n)
target = n; target = n;
acquire(&cons.lock); acquire(&cons.lock);
while(n > 0){ while(n > 0) {
// wait until interrupt handler has put some // wait until interrupt handler has put some
// input into cons.buffer. // input into cons.buffer.
while(cons.r == cons.w){ while(cons.r == cons.w) {
if(killed(myproc())){ if(killed(myproc())) {
release(&cons.lock); release(&cons.lock);
return -1; return -1;
} }
@ -98,8 +100,8 @@ consoleread(int user_dst, u64 dst, int n)
c = cons.buf[cons.r++ % INPUT_BUF_SIZE]; c = cons.buf[cons.r++ % INPUT_BUF_SIZE];
if(c == C('D')){ // end-of-file if(c == C('D')) { // end-of-file
if(n < target){ if(n < target) {
// Save ^D for next time, to make sure // Save ^D for next time, to make sure
// caller gets a 0-byte result. // caller gets a 0-byte result.
cons.r--; cons.r--;
@ -115,7 +117,7 @@ consoleread(int user_dst, u64 dst, int n)
dst++; dst++;
--n; --n;
if(c == '\n'){ if(c == '\n') {
// a whole line has arrived, return to // a whole line has arrived, return to
// the user-level read(). // the user-level read().
break; break;
@ -137,26 +139,25 @@ consoleintr(int c)
{ {
acquire(&cons.lock); acquire(&cons.lock);
switch(c){ switch(c) {
case C('P'): // Print process list. case C('P'): // Print process list.
procdump(); procdump();
break; break;
case C('U'): // Kill line. case C('U'): // Kill line.
while(cons.e != cons.w && while(cons.e != cons.w && cons.buf[(cons.e - 1) % INPUT_BUF_SIZE] != '\n') {
cons.buf[(cons.e-1) % INPUT_BUF_SIZE] != '\n'){
cons.e--; cons.e--;
consputc(BACKSPACE); consputc(BACKSPACE);
} }
break; break;
case C('H'): // Backspace case C('H'): // Backspace
case '\x7f': // Delete key case '\x7f': // Delete key
if(cons.e != cons.w){ if(cons.e != cons.w) {
cons.e--; cons.e--;
consputc(BACKSPACE); consputc(BACKSPACE);
} }
break; break;
default: default:
if(c != 0 && cons.e-cons.r < INPUT_BUF_SIZE){ if(c != 0 && cons.e - cons.r < INPUT_BUF_SIZE) {
c = (c == '\r') ? '\n' : c; c = (c == '\r') ? '\n' : c;
// echo back to the user. // echo back to the user.
@ -165,7 +166,7 @@ consoleintr(int c)
// store for consumption by consoleread(). // store for consumption by consoleread().
cons.buf[cons.e++ % INPUT_BUF_SIZE] = c; cons.buf[cons.e++ % INPUT_BUF_SIZE] = c;
if(c == '\n' || c == C('D') || cons.e-cons.r == INPUT_BUF_SIZE){ if(c == '\n' || c == C('D') || cons.e - cons.r == INPUT_BUF_SIZE) {
// wake up consoleread() if a whole line (or end-of-file) // wake up consoleread() if a whole line (or end-of-file)
// has arrived. // has arrived.
cons.w = cons.e; cons.w = cons.e;

134
kernel/defs.h
View file

@ -11,11 +11,11 @@ struct superblock;
// bio.c // bio.c
void binit(void); void binit(void);
struct buf* bread(u32, u32); struct buf *bread(u32, u32);
void brelse(struct buf*); void brelse(struct buf *);
void bwrite(struct buf*); void bwrite(struct buf *);
void bpin(struct buf*); void bpin(struct buf *);
void bunpin(struct buf*); void bunpin(struct buf *);
// console.c // console.c
void consoleinit(void); void consoleinit(void);
@ -23,62 +23,62 @@ void consoleintr(int);
void consputc(int); void consputc(int);
// exec.c // exec.c
int exec(char*, char**); int exec(char *, char **);
// file.c // file.c
struct file* filealloc(void); struct file *filealloc(void);
void fileclose(struct file*); void fileclose(struct file *);
struct file* filedup(struct file*); struct file *filedup(struct file *);
void fileinit(void); void fileinit(void);
int fileread(struct file*, u64, int n); int fileread(struct file *, u64, int n);
int filestat(struct file*, u64 addr); int filestat(struct file *, u64 addr);
int filewrite(struct file*, u64, int n); int filewrite(struct file *, u64, int n);
// fs.c // fs.c
void fsinit(int); void fsinit(int);
int dirlink(struct inode*, char*, u32); int dirlink(struct inode *, char *, u32);
struct inode* dirlookup(struct inode*, char*, u32*); struct inode *dirlookup(struct inode *, char *, u32 *);
struct inode* ialloc(u32, short); struct inode *ialloc(u32, short);
struct inode* idup(struct inode*); struct inode *idup(struct inode *);
void iinit(); void iinit();
void ilock(struct inode*); void ilock(struct inode *);
void iput(struct inode*); void iput(struct inode *);
void iunlock(struct inode*); void iunlock(struct inode *);
void iunlockput(struct inode*); void iunlockput(struct inode *);
void iupdate(struct inode*); void iupdate(struct inode *);
int namecmp(const char*, const char*); int namecmp(const char *, const char *);
struct inode* namei(char*); struct inode *namei(char *);
struct inode* nameiparent(char*, char*); struct inode *nameiparent(char *, char *);
int readi(struct inode*, int, u64, u32, u32); int readi(struct inode *, int, u64, u32, u32);
void stati(struct inode*, struct stat*); void stati(struct inode *, struct stat *);
int writei(struct inode*, int, u64, u32, u32); int writei(struct inode *, int, u64, u32, u32);
void itrunc(struct inode*); void itrunc(struct inode *);
// ramdisk.c // ramdisk.c
void ramdiskinit(void); void ramdiskinit(void);
void ramdiskintr(void); void ramdiskintr(void);
void ramdiskrw(struct buf*); void ramdiskrw(struct buf *);
// kalloc.c // kalloc.c
void* kalloc(void); void *kalloc(void);
void kfree(void *); void kfree(void *);
void kinit(void); void kinit(void);
// log.c // log.c
void initlog(int, struct superblock*); void initlog(int, struct superblock *);
void log_write(struct buf*); void log_write(struct buf *);
void begin_op(void); void begin_op(void);
void end_op(void); void end_op(void);
// pipe.c // pipe.c
int pipealloc(struct file**, struct file**); int pipealloc(struct file **, struct file **);
void pipeclose(struct pipe*, int); void pipeclose(struct pipe *, int);
int piperead(struct pipe*, u64, int); int piperead(struct pipe *, u64, int);
int pipewrite(struct pipe*, u64, int); int pipewrite(struct pipe *, u64, int);
// printf.c // printf.c
void printf(char*, ...); void printf(char *, ...);
void panic(char*) __attribute__((noreturn)); void panic(char *) __attribute__((noreturn));
void printfinit(void); void printfinit(void);
// proc.c // proc.c
@ -90,55 +90,55 @@ void proc_mapstacks(pagetable_t);
pagetable_t proc_pagetable(struct proc *); pagetable_t proc_pagetable(struct proc *);
void proc_freepagetable(pagetable_t, u64); void proc_freepagetable(pagetable_t, u64);
int kill(int); int kill(int);
int killed(struct proc*); int killed(struct proc *);
void setkilled(struct proc*); void setkilled(struct proc *);
struct cpu* mycpu(void); struct cpu *mycpu(void);
struct cpu* getmycpu(void); struct cpu *getmycpu(void);
struct proc* myproc(); struct proc *myproc();
void procinit(void); void procinit(void);
void scheduler(void) __attribute__((noreturn)); void scheduler(void) __attribute__((noreturn));
void sched(void); void sched(void);
void sleep(void*, struct spinlock*); void sleep(void *, struct spinlock *);
void userinit(void); void userinit(void);
int wait(u64); int wait(u64);
void wakeup(void*); void wakeup(void *);
void yield(void); void yield(void);
int either_copyout(int user_dst, u64 dst, void *src, u64 len); int either_copyout(int user_dst, u64 dst, void *src, u64 len);
int either_copyin(void *dst, int user_src, u64 src, u64 len); int either_copyin(void *dst, int user_src, u64 src, u64 len);
void procdump(void); void procdump(void);
// swtch.S // swtch.S
void swtch(struct context*, struct context*); void swtch(struct context *, struct context *);
// spinlock.c // spinlock.c
void acquire(struct spinlock*); void acquire(struct spinlock *);
int holding(struct spinlock*); int holding(struct spinlock *);
void initlock(struct spinlock*, char*); void initlock(struct spinlock *, char *);
void release(struct spinlock*); void release(struct spinlock *);
void push_off(void); void push_off(void);
void pop_off(void); void pop_off(void);
// sleeplock.c // sleeplock.c
void acquiresleep(struct sleeplock*); void acquiresleep(struct sleeplock *);
void releasesleep(struct sleeplock*); void releasesleep(struct sleeplock *);
int holdingsleep(struct sleeplock*); int holdingsleep(struct sleeplock *);
void initsleeplock(struct sleeplock*, char*); void initsleeplock(struct sleeplock *, char *);
// string.c // string.c
int memcmp(const void*, const void*, u32); int memcmp(const void *, const void *, u32);
void* memmove(void*, const void*, u32); void *memmove(void *, const void *, u32);
void* memset(void*, int, u32); void *memset(void *, int, u32);
char* safestrcpy(char*, const char*, int); char *safestrcpy(char *, const char *, int);
int strlen(const char*); int strlen(const char *);
int strncmp(const char*, const char*, u32); int strncmp(const char *, const char *, u32);
char* strncpy(char*, const char*, int); char *strncpy(char *, const char *, int);
// syscall.c // syscall.c
void argint(int, int*); void argint(int, int *);
int argstr(int, char*, int); int argstr(int, char *, int);
void argaddr(int, u64 *); void argaddr(int, u64 *);
int fetchstr(u64, char*, int); int fetchstr(u64, char *, int);
int fetchaddr(u64, u64*); int fetchaddr(u64, u64 *);
void syscall(); void syscall();
// trap.c // trap.c
@ -168,7 +168,7 @@ int uvmcopy(pagetable_t, pagetable_t, u64);
void uvmfree(pagetable_t, u64); void uvmfree(pagetable_t, u64);
void uvmunmap(pagetable_t, u64, u64, int); void uvmunmap(pagetable_t, u64, u64, int);
void uvmclear(pagetable_t, u64); void uvmclear(pagetable_t, u64);
pte_t * walk(pagetable_t, u64, int); pte_t *walk(pagetable_t, u64, int);
u64 walkaddr(pagetable_t, u64); u64 walkaddr(pagetable_t, u64);
int copyout(pagetable_t, u64, char *, u64); int copyout(pagetable_t, u64, char *, u64);
int copyin(pagetable_t, char *, u64, u64); int copyin(pagetable_t, char *, u64, u64);
@ -186,4 +186,4 @@ void virtio_disk_rw(struct buf *, int);
void virtio_disk_intr(void); void virtio_disk_intr(void);
// number of elements in fixed-size array // number of elements in fixed-size array
#define NELEM(x) (sizeof(x)/sizeof((x)[0])) #define NELEM(x) (sizeof(x) / sizeof((x)[0]))

27
kernel/exec.c
View file

@ -9,7 +9,8 @@
static int loadseg(pde_t *, u64, struct inode *, u32, u32); static int loadseg(pde_t *, u64, struct inode *, u32, u32);
int flags2perm(int flags) int
flags2perm(int flags)
{ {
int perm = 0; int perm = 0;
if(flags & 0x1) if(flags & 0x1)
@ -33,7 +34,7 @@ exec(char *path, char **argv)
begin_op(); begin_op();
if((ip = namei(path)) == 0){ if((ip = namei(path)) == 0) {
end_op(); end_op();
return -1; return -1;
} }
@ -50,7 +51,7 @@ exec(char *path, char **argv)
goto bad; goto bad;
// Load program into memory. // Load program into memory.
for(i=0, off=elf.phoff; i<elf.phnum; i++, off+=sizeof(ph)){ for(i = 0, off = elf.phoff; i < elf.phnum; i++, off += sizeof(ph)) {
if(readi(ip, 0, (u64)&ph, off, sizeof(ph)) != sizeof(ph)) if(readi(ip, 0, (u64)&ph, off, sizeof(ph)) != sizeof(ph))
goto bad; goto bad;
if(ph.type != ELF_PROG_LOAD) if(ph.type != ELF_PROG_LOAD)
@ -80,10 +81,10 @@ exec(char *path, char **argv)
// Use the second as the user stack. // Use the second as the user stack.
sz = PGROUNDUP(sz); sz = PGROUNDUP(sz);
u64 sz1; u64 sz1;
if((sz1 = uvmalloc(pagetable, sz, sz + 2*PGSIZE, PTE_W)) == 0) if((sz1 = uvmalloc(pagetable, sz, sz + 2 * PGSIZE, PTE_W)) == 0)
goto bad; goto bad;
sz = sz1; sz = sz1;
uvmclear(pagetable, sz-2*PGSIZE); uvmclear(pagetable, sz - 2 * PGSIZE);
sp = sz; sp = sz;
stackbase = sp - PGSIZE; stackbase = sp - PGSIZE;
@ -102,11 +103,11 @@ exec(char *path, char **argv)
ustack[argc] = 0; ustack[argc] = 0;
// push the array of argv[] pointers. // push the array of argv[] pointers.
sp -= (argc+1) * sizeof(u64); sp -= (argc + 1) * sizeof(u64);
sp -= sp % 16; sp -= sp % 16;
if(sp < stackbase) if(sp < stackbase)
goto bad; goto bad;
if(copyout(pagetable, sp, (char *)ustack, (argc+1)*sizeof(u64)) < 0) if(copyout(pagetable, sp, (char *)ustack, (argc + 1) * sizeof(u64)) < 0)
goto bad; goto bad;
// arguments to user main(argc, argv) // arguments to user main(argc, argv)
@ -115,9 +116,9 @@ exec(char *path, char **argv)
p->trapframe->a1 = sp; p->trapframe->a1 = sp;
// Save program name for debugging. // Save program name for debugging.
for(last=s=path; *s; s++) for(last = s = path; *s; s++)
if(*s == '/') if(*s == '/')
last = s+1; last = s + 1;
safestrcpy(p->name, last, sizeof(p->name)); safestrcpy(p->name, last, sizeof(p->name));
// Commit to the user image. // Commit to the user image.
@ -130,10 +131,10 @@ exec(char *path, char **argv)
return argc; // this ends up in a0, the first argument to main(argc, argv) return argc; // this ends up in a0, the first argument to main(argc, argv)
bad: bad:
if(pagetable) if(pagetable)
proc_freepagetable(pagetable, sz); proc_freepagetable(pagetable, sz);
if(ip){ if(ip) {
iunlockput(ip); iunlockput(ip);
end_op(); end_op();
} }
@ -150,7 +151,7 @@ loadseg(pagetable_t pagetable, u64 va, struct inode *ip, u32 offset, u32 sz)
u32 i, n; u32 i, n;
u64 pa; u64 pa;
for(i = 0; i < sz; i += PGSIZE){ for(i = 0; i < sz; i += PGSIZE) {
pa = walkaddr(pagetable, va + i); pa = walkaddr(pagetable, va + i);
if(pa == 0) if(pa == 0)
panic("loadseg: address should exist"); panic("loadseg: address should exist");
@ -158,7 +159,7 @@ loadseg(pagetable_t pagetable, u64 va, struct inode *ip, u32 offset, u32 sz)
n = sz - i; n = sz - i;
else else
n = PGSIZE; n = PGSIZE;
if(readi(ip, 0, (u64)pa, offset+i, n) != n) if(readi(ip, 0, (u64)pa, offset + i, n) != n)
return -1; return -1;
} }

37
kernel/file.c
View file

@ -26,14 +26,14 @@ fileinit(void)
} }
// Allocate a file structure. // Allocate a file structure.
struct file* struct file *
filealloc(void) filealloc(void)
{ {
struct file *f; struct file *f;
acquire(&ftable.lock); acquire(&ftable.lock);
for(f = ftable.file; f < ftable.file + NFILE; f++){ for(f = ftable.file; f < ftable.file + NFILE; f++) {
if(f->ref == 0){ if(f->ref == 0) {
f->ref = 1; f->ref = 1;
release(&ftable.lock); release(&ftable.lock);
return f; return f;
@ -44,7 +44,7 @@ filealloc(void)
} }
// Increment ref count for file f. // Increment ref count for file f.
struct file* struct file *
filedup(struct file *f) filedup(struct file *f)
{ {
acquire(&ftable.lock); acquire(&ftable.lock);
@ -64,7 +64,7 @@ fileclose(struct file *f)
acquire(&ftable.lock); acquire(&ftable.lock);
if(f->ref < 1) if(f->ref < 1)
panic("fileclose"); panic("fileclose");
if(--f->ref > 0){ if(--f->ref > 0) {
release(&ftable.lock); release(&ftable.lock);
return; return;
} }
@ -73,9 +73,9 @@ fileclose(struct file *f)
f->type = FD_NONE; f->type = FD_NONE;
release(&ftable.lock); release(&ftable.lock);
if(ff.type == FD_PIPE){ if(ff.type == FD_PIPE) {
pipeclose(ff.pipe, ff.writable); pipeclose(ff.pipe, ff.writable);
} else if(ff.type == FD_INODE || ff.type == FD_DEVICE){ } else if(ff.type == FD_INODE || ff.type == FD_DEVICE) {
begin_op(); begin_op();
iput(ff.ip); iput(ff.ip);
end_op(); end_op();
@ -90,7 +90,7 @@ filestat(struct file *f, u64 addr)
struct proc *p = myproc(); struct proc *p = myproc();
struct stat st; struct stat st;
if(f->type == FD_INODE || f->type == FD_DEVICE){ if(f->type == FD_INODE || f->type == FD_DEVICE) {
ilock(f->ip); ilock(f->ip);
stati(f->ip, &st); stati(f->ip, &st);
iunlock(f->ip); iunlock(f->ip);
@ -111,13 +111,13 @@ fileread(struct file *f, u64 addr, int n)
if(f->readable == 0) if(f->readable == 0)
return -1; return -1;
if(f->type == FD_PIPE){ if(f->type == FD_PIPE) {
r = piperead(f->pipe, addr, n); r = piperead(f->pipe, addr, n);
} else if(f->type == FD_DEVICE){ } else if(f->type == FD_DEVICE) {
if(f->major < 0 || f->major >= NDEV || !devsw[f->major].read) if(f->major < 0 || f->major >= NDEV || !devsw[f->major].read)
return -1; return -1;
r = devsw[f->major].read(1, addr, n); r = devsw[f->major].read(1, addr, n);
} else if(f->type == FD_INODE){ } else if(f->type == FD_INODE) {
ilock(f->ip); ilock(f->ip);
if((r = readi(f->ip, 1, addr, f->off, n)) > 0) if((r = readi(f->ip, 1, addr, f->off, n)) > 0)
f->off += r; f->off += r;
@ -139,34 +139,34 @@ filewrite(struct file *f, u64 addr, int n)
if(f->writable == 0) if(f->writable == 0)
return -1; return -1;
if(f->type == FD_PIPE){ if(f->type == FD_PIPE) {
ret = pipewrite(f->pipe, addr, n); ret = pipewrite(f->pipe, addr, n);
} else if(f->type == FD_DEVICE){ } else if(f->type == FD_DEVICE) {
if(f->major < 0 || f->major >= NDEV || !devsw[f->major].write) if(f->major < 0 || f->major >= NDEV || !devsw[f->major].write)
return -1; return -1;
ret = devsw[f->major].write(1, addr, n); ret = devsw[f->major].write(1, addr, n);
} else if(f->type == FD_INODE){ } else if(f->type == FD_INODE) {
// write a few blocks at a time to avoid exceeding // write a few blocks at a time to avoid exceeding
// the maximum log transaction size, including // the maximum log transaction size, including
// i-node, indirect block, allocation blocks, // i-node, indirect block, allocation blocks,
// and 2 blocks of slop for non-aligned writes. // and 2 blocks of slop for non-aligned writes.
// this really belongs lower down, since writei() // this really belongs lower down, since writei()
// might be writing a device like the console. // might be writing a device like the console.
int max = ((MAXOPBLOCKS-1-1-2) / 2) * BSIZE; int max = ((MAXOPBLOCKS - 1 - 1 - 2) / 2) * BSIZE;
int i = 0; int i = 0;
while(i < n){ while(i < n) {
int n1 = n - i; int n1 = n - i;
if(n1 > max) if(n1 > max)
n1 = max; n1 = max;
begin_op(); begin_op();
ilock(f->ip); ilock(f->ip);
if ((r = writei(f->ip, 1, addr + i, f->off, n1)) > 0) if((r = writei(f->ip, 1, addr + i, f->off, n1)) > 0)
f->off += r; f->off += r;
iunlock(f->ip); iunlock(f->ip);
end_op(); end_op();
if(r != n1){ if(r != n1) {
// error from writei // error from writei
break; break;
} }
@ -179,4 +179,3 @@ filewrite(struct file *f, u64 addr, int n)
return ret; return ret;
} }

4
kernel/file.h
View file

@ -11,7 +11,7 @@ struct file {
#define major(dev) ((dev) >> 16 & 0xFFFF) #define major(dev) ((dev) >> 16 & 0xFFFF)
#define minor(dev) ((dev) & 0xFFFF) #define minor(dev) ((dev) & 0xFFFF)
#define mkdev(m,n) ((u32)((m)<<16| (n))) #define mkdev(m, n) ((u32)((m) << 16 | (n)))
// in-memory copy of an inode // in-memory copy of an inode
struct inode { struct inode {
@ -26,7 +26,7 @@ struct inode {
short minor; short minor;
short nlink; short nlink;
u32 size; u32 size;
u32 addrs[NDIRECT+1]; u32 addrs[NDIRECT + 1];
}; };
// map major device number to device functions. // map major device number to device functions.

107
kernel/fs.c
View file

@ -39,7 +39,8 @@ readsb(int dev, struct superblock *sb)
// Init fs // Init fs
void void
fsinit(int dev) { fsinit(int dev)
{
readsb(dev, &sb); readsb(dev, &sb);
if(sb.magic != FSMAGIC) if(sb.magic != FSMAGIC)
panic("invalid file system"); panic("invalid file system");
@ -69,12 +70,12 @@ balloc(u32 dev)
struct buf *bp; struct buf *bp;
bp = 0; bp = 0;
for(b = 0; b < sb.size; b += BPB){ for(b = 0; b < sb.size; b += BPB) {
bp = bread(dev, BBLOCK(b, sb)); bp = bread(dev, BBLOCK(b, sb));
for(bi = 0; bi < BPB && b + bi < sb.size; bi++){ for(bi = 0; bi < BPB && b + bi < sb.size; bi++) {
m = 1 << (bi % 8); m = 1 << (bi % 8);
if((bp->data[bi/8] & m) == 0){ // Is block free? if((bp->data[bi / 8] & m) == 0) { // Is block free?
bp->data[bi/8] |= m; // Mark block in use. bp->data[bi / 8] |= m; // Mark block in use.
log_write(bp); log_write(bp);
brelse(bp); brelse(bp);
bzero(dev, b + bi); bzero(dev, b + bi);
@ -97,9 +98,9 @@ bfree(int dev, u32 b)
bp = bread(dev, BBLOCK(b, sb)); bp = bread(dev, BBLOCK(b, sb));
bi = b % BPB; bi = b % BPB;
m = 1 << (bi % 8); m = 1 << (bi % 8);
if((bp->data[bi/8] & m) == 0) if((bp->data[bi / 8] & m) == 0)
panic("freeing free block"); panic("freeing free block");
bp->data[bi/8] &= ~m; bp->data[bi / 8] &= ~m;
log_write(bp); log_write(bp);
brelse(bp); brelse(bp);
} }
@ -189,23 +190,23 @@ iinit()
} }
} }
static struct inode* iget(u32 dev, u32 inum); static struct inode *iget(u32 dev, u32 inum);
// Allocate an inode on device dev. // Allocate an inode on device dev.
// Mark it as allocated by giving it type type. // Mark it as allocated by giving it type type.
// Returns an unlocked but allocated and referenced inode, // Returns an unlocked but allocated and referenced inode,
// or NULL if there is no free inode. // or NULL if there is no free inode.
struct inode* struct inode *
ialloc(u32 dev, short type) ialloc(u32 dev, short type)
{ {
int inum; int inum;
struct buf *bp; struct buf *bp;
struct dinode *dip; struct dinode *dip;
for(inum = 1; inum < sb.ninodes; inum++){ for(inum = 1; inum < sb.ninodes; inum++) {
bp = bread(dev, IBLOCK(inum, sb)); bp = bread(dev, IBLOCK(inum, sb));
dip = (struct dinode*)bp->data + inum%IPB; dip = (struct dinode *)bp->data + inum % IPB;
if(dip->type == 0){ // a free inode if(dip->type == 0) { // a free inode
memset(dip, 0, sizeof(*dip)); memset(dip, 0, sizeof(*dip));
dip->type = type; dip->type = type;
log_write(bp); // mark it allocated on the disk log_write(bp); // mark it allocated on the disk
@ -229,7 +230,7 @@ iupdate(struct inode *ip)
struct dinode *dip; struct dinode *dip;
bp = bread(ip->dev, IBLOCK(ip->inum, sb)); bp = bread(ip->dev, IBLOCK(ip->inum, sb));
dip = (struct dinode*)bp->data + ip->inum%IPB; dip = (struct dinode *)bp->data + ip->inum % IPB;
dip->type = ip->type; dip->type = ip->type;
dip->major = ip->major; dip->major = ip->major;
dip->minor = ip->minor; dip->minor = ip->minor;
@ -243,7 +244,7 @@ iupdate(struct inode *ip)
// Find the inode with number inum on device dev // Find the inode with number inum on device dev
// and return the in-memory copy. Does not lock // and return the in-memory copy. Does not lock
// the inode and does not read it from disk. // the inode and does not read it from disk.
static struct inode* static struct inode *
iget(u32 dev, u32 inum) iget(u32 dev, u32 inum)
{ {
struct inode *ip, *empty; struct inode *ip, *empty;
@ -252,8 +253,8 @@ iget(u32 dev, u32 inum)
// Is the inode already in the table? // Is the inode already in the table?
empty = 0; empty = 0;
for(ip = &itable.inode[0]; ip < &itable.inode[NINODE]; ip++){ for(ip = &itable.inode[0]; ip < &itable.inode[NINODE]; ip++) {
if(ip->ref > 0 && ip->dev == dev && ip->inum == inum){ if(ip->ref > 0 && ip->dev == dev && ip->inum == inum) {
ip->ref++; ip->ref++;
release(&itable.lock); release(&itable.lock);
return ip; return ip;
@ -278,7 +279,7 @@ iget(u32 dev, u32 inum)
// Increment reference count for ip. // Increment reference count for ip.
// Returns ip to enable ip = idup(ip1) idiom. // Returns ip to enable ip = idup(ip1) idiom.
struct inode* struct inode *
idup(struct inode *ip) idup(struct inode *ip)
{ {
acquire(&itable.lock); acquire(&itable.lock);
@ -300,9 +301,9 @@ ilock(struct inode *ip)
acquiresleep(&ip->lock); acquiresleep(&ip->lock);
if(ip->valid == 0){ if(ip->valid == 0) {
bp = bread(ip->dev, IBLOCK(ip->inum, sb)); bp = bread(ip->dev, IBLOCK(ip->inum, sb));
dip = (struct dinode*)bp->data + ip->inum%IPB; dip = (struct dinode *)bp->data + ip->inum % IPB;
ip->type = dip->type; ip->type = dip->type;
ip->major = dip->major; ip->major = dip->major;
ip->minor = dip->minor; ip->minor = dip->minor;
@ -338,7 +339,7 @@ iput(struct inode *ip)
{ {
acquire(&itable.lock); acquire(&itable.lock);
if(ip->ref == 1 && ip->valid && ip->nlink == 0){ if(ip->ref == 1 && ip->valid && ip->nlink == 0) {
// inode has no links and no other references: truncate and free. // inode has no links and no other references: truncate and free.
// ip->ref == 1 means no other process can have ip locked, // ip->ref == 1 means no other process can have ip locked,
@ -385,8 +386,8 @@ bmap(struct inode *ip, u32 bn)
u32 addr, *a; u32 addr, *a;
struct buf *bp; struct buf *bp;
if(bn < NDIRECT){ if(bn < NDIRECT) {
if((addr = ip->addrs[bn]) == 0){ if((addr = ip->addrs[bn]) == 0) {
addr = balloc(ip->dev); addr = balloc(ip->dev);
if(addr == 0) if(addr == 0)
return 0; return 0;
@ -396,19 +397,19 @@ bmap(struct inode *ip, u32 bn)
} }
bn -= NDIRECT; bn -= NDIRECT;
if(bn < NINDIRECT){ if(bn < NINDIRECT) {
// Load indirect block, allocating if necessary. // Load indirect block, allocating if necessary.
if((addr = ip->addrs[NDIRECT]) == 0){ if((addr = ip->addrs[NDIRECT]) == 0) {
addr = balloc(ip->dev); addr = balloc(ip->dev);
if(addr == 0) if(addr == 0)
return 0; return 0;
ip->addrs[NDIRECT] = addr; ip->addrs[NDIRECT] = addr;
} }
bp = bread(ip->dev, addr); bp = bread(ip->dev, addr);
a = (u32*)bp->data; a = (u32 *)bp->data;
if((addr = a[bn]) == 0){ if((addr = a[bn]) == 0) {
addr = balloc(ip->dev); addr = balloc(ip->dev);
if(addr){ if(addr) {
a[bn] = addr; a[bn] = addr;
log_write(bp); log_write(bp);
} }
@ -429,17 +430,17 @@ itrunc(struct inode *ip)
struct buf *bp; struct buf *bp;
u32 *a; u32 *a;
for(i = 0; i < NDIRECT; i++){ for(i = 0; i < NDIRECT; i++) {
if(ip->addrs[i]){ if(ip->addrs[i]) {
bfree(ip->dev, ip->addrs[i]); bfree(ip->dev, ip->addrs[i]);
ip->addrs[i] = 0; ip->addrs[i] = 0;
} }
} }
if(ip->addrs[NDIRECT]){ if(ip->addrs[NDIRECT]) {
bp = bread(ip->dev, ip->addrs[NDIRECT]); bp = bread(ip->dev, ip->addrs[NDIRECT]);
a = (u32*)bp->data; a = (u32 *)bp->data;
for(j = 0; j < NINDIRECT; j++){ for(j = 0; j < NINDIRECT; j++) {
if(a[j]) if(a[j])
bfree(ip->dev, a[j]); bfree(ip->dev, a[j]);
} }
@ -479,12 +480,12 @@ readi(struct inode *ip, int user_dst, u64 dst, u32 off, u32 n)
if(off + n > ip->size) if(off + n > ip->size)
n = ip->size - off; n = ip->size - off;
for(tot=0; tot<n; tot+=m, off+=m, dst+=m){ for(tot = 0; tot < n; tot += m, off += m, dst += m) {
u32 addr = bmap(ip, off/BSIZE); u32 addr = bmap(ip, off / BSIZE);
if(addr == 0) if(addr == 0)
break; break;
bp = bread(ip->dev, addr); bp = bread(ip->dev, addr);
m = min(n - tot, BSIZE - off%BSIZE); m = min(n - tot, BSIZE - off % BSIZE);
if(either_copyout(user_dst, dst, bp->data + (off % BSIZE), m) == -1) { if(either_copyout(user_dst, dst, bp->data + (off % BSIZE), m) == -1) {
brelse(bp); brelse(bp);
tot = -1; tot = -1;
@ -510,15 +511,15 @@ writei(struct inode *ip, int user_src, u64 src, u32 off, u32 n)
if(off > ip->size || off + n < off) if(off > ip->size || off + n < off)
return -1; return -1;
if(off + n > MAXFILE*BSIZE) if(off + n > MAXFILE * BSIZE)
return -1; return -1;
for(tot=0; tot<n; tot+=m, off+=m, src+=m){ for(tot = 0; tot < n; tot += m, off += m, src += m) {
u32 addr = bmap(ip, off/BSIZE); u32 addr = bmap(ip, off / BSIZE);
if(addr == 0) if(addr == 0)
break; break;
bp = bread(ip->dev, addr); bp = bread(ip->dev, addr);
m = min(n - tot, BSIZE - off%BSIZE); m = min(n - tot, BSIZE - off % BSIZE);
if(either_copyin(bp->data + (off % BSIZE), user_src, src, m) == -1) { if(either_copyin(bp->data + (off % BSIZE), user_src, src, m) == -1) {
brelse(bp); brelse(bp);
break; break;
@ -548,7 +549,7 @@ namecmp(const char *s, const char *t)
// Look for a directory entry in a directory. // Look for a directory entry in a directory.
// If found, set *poff to byte offset of entry. // If found, set *poff to byte offset of entry.
struct inode* struct inode *
dirlookup(struct inode *dp, char *name, u32 *poff) dirlookup(struct inode *dp, char *name, u32 *poff)
{ {
u32 off, inum; u32 off, inum;
@ -557,12 +558,12 @@ dirlookup(struct inode *dp, char *name, u32 *poff)
if(dp->type != T_DIR) if(dp->type != T_DIR)
panic("dirlookup not DIR"); panic("dirlookup not DIR");
for(off = 0; off < dp->size; off += sizeof(de)){ for(off = 0; off < dp->size; off += sizeof(de)) {
if(readi(dp, 0, (u64)&de, off, sizeof(de)) != sizeof(de)) if(readi(dp, 0, (u64)&de, off, sizeof(de)) != sizeof(de))
panic("dirlookup read"); panic("dirlookup read");
if(de.inum == 0) if(de.inum == 0)
continue; continue;
if(namecmp(name, de.name) == 0){ if(namecmp(name, de.name) == 0) {
// entry matches path element // entry matches path element
if(poff) if(poff)
*poff = off; *poff = off;
@ -584,13 +585,13 @@ dirlink(struct inode *dp, char *name, u32 inum)
struct inode *ip; struct inode *ip;
// Check that name is not present. // Check that name is not present.
if((ip = dirlookup(dp, name, 0)) != 0){ if((ip = dirlookup(dp, name, 0)) != 0) {
iput(ip); iput(ip);
return -1; return -1;
} }
// Look for an empty dirent. // Look for an empty dirent.
for(off = 0; off < dp->size; off += sizeof(de)){ for(off = 0; off < dp->size; off += sizeof(de)) {
if(readi(dp, 0, (u64)&de, off, sizeof(de)) != sizeof(de)) if(readi(dp, 0, (u64)&de, off, sizeof(de)) != sizeof(de))
panic("dirlink read"); panic("dirlink read");
if(de.inum == 0) if(de.inum == 0)
@ -619,7 +620,7 @@ dirlink(struct inode *dp, char *name, u32 inum)
// skipelem("a", name) = "", setting name = "a" // skipelem("a", name) = "", setting name = "a"
// skipelem("", name) = skipelem("////", name) = 0 // skipelem("", name) = skipelem("////", name) = 0
// //
static char* static char *
skipelem(char *path, char *name) skipelem(char *path, char *name)
{ {
char *s; char *s;
@ -648,7 +649,7 @@ skipelem(char *path, char *name)
// If parent != 0, return the inode for the parent and copy the final // If parent != 0, return the inode for the parent and copy the final
// path element into name, which must have room for DIRSIZ bytes. // path element into name, which must have room for DIRSIZ bytes.
// Must be called inside a transaction since it calls iput(). // Must be called inside a transaction since it calls iput().
static struct inode* static struct inode *
namex(char *path, int nameiparent, char *name) namex(char *path, int nameiparent, char *name)
{ {
struct inode *ip, *next; struct inode *ip, *next;
@ -658,39 +659,39 @@ namex(char *path, int nameiparent, char *name)
else else
ip = idup(myproc()->cwd); ip = idup(myproc()->cwd);
while((path = skipelem(path, name)) != 0){ while((path = skipelem(path, name)) != 0) {
ilock(ip); ilock(ip);
if(ip->type != T_DIR){ if(ip->type != T_DIR) {
iunlockput(ip); iunlockput(ip);
return 0; return 0;
} }
if(nameiparent && *path == '\0'){ if(nameiparent && *path == '\0') {
// Stop one level early. // Stop one level early.
iunlock(ip); iunlock(ip);
return ip; return ip;
} }
if((next = dirlookup(ip, name, 0)) == 0){ if((next = dirlookup(ip, name, 0)) == 0) {
iunlockput(ip); iunlockput(ip);
return 0; return 0;
} }
iunlockput(ip); iunlockput(ip);
ip = next; ip = next;
} }
if(nameiparent){ if(nameiparent) {
iput(ip); iput(ip);
return 0; return 0;
} }
return ip; return ip;
} }
struct inode* struct inode *
namei(char *path) namei(char *path)
{ {
char name[DIRSIZ]; char name[DIRSIZ];
return namex(path, 0, name); return namex(path, 0, name);
} }
struct inode* struct inode *
nameiparent(char *path, char *name) nameiparent(char *path, char *name)
{ {
return namex(path, 1, name); return namex(path, 1, name);

8
kernel/fs.h
View file

@ -1,7 +1,6 @@
// On-disk file system format. // On-disk file system format.
// Both the kernel and user programs use this header file. // Both the kernel and user programs use this header file.
#define ROOTINO 1 // root i-number #define ROOTINO 1 // root i-number
#define BSIZE 1024 // block size #define BSIZE 1024 // block size
@ -35,7 +34,7 @@ struct dinode {
short minor; // Minor device number (T_DEVICE only) short minor; // Minor device number (T_DEVICE only)
short nlink; // Number of links to inode in file system short nlink; // Number of links to inode in file system
u32 size; // Size of file (bytes) u32 size; // Size of file (bytes)
u32 addrs[NDIRECT+1]; // Data block addresses u32 addrs[NDIRECT + 1]; // Data block addresses
}; };
// Inodes per block. // Inodes per block.
@ -45,10 +44,10 @@ struct dinode {
#define IBLOCK(i, sb) ((i) / IPB + sb.inodestart) #define IBLOCK(i, sb) ((i) / IPB + sb.inodestart)
// Bitmap bits per block // Bitmap bits per block
#define BPB (BSIZE*8) #define BPB (BSIZE * 8)
// Block of free map containing bit for block b // Block of free map containing bit for block b
#define BBLOCK(b, sb) ((b)/BPB + sb.bmapstart) #define BBLOCK(b, sb) ((b) / BPB + sb.bmapstart)
// Directory is a file containing a sequence of dirent structures. // Directory is a file containing a sequence of dirent structures.
#define DIRSIZ 14 #define DIRSIZ 14
@ -57,4 +56,3 @@ struct dirent {
u16 inum; u16 inum;
char name[DIRSIZ]; char name[DIRSIZ];
}; };

14
kernel/kalloc.c
View file

@ -27,15 +27,15 @@ void
kinit() kinit()
{ {
initlock(&kmem.lock, "kmem"); initlock(&kmem.lock, "kmem");
freerange(end, (void*)PHYSTOP); freerange(end, (void *)PHYSTOP);
} }
void void
freerange(void *pa_start, void *pa_end) freerange(void *pa_start, void *pa_end)
{ {
char *p; char *p;
p = (char*)PGROUNDUP((u64)pa_start); p = (char *)PGROUNDUP((u64)pa_start);
for(; p + PGSIZE <= (char*)pa_end; p += PGSIZE) for(; p + PGSIZE <= (char *)pa_end; p += PGSIZE)
kfree(p); kfree(p);
} }
@ -48,13 +48,13 @@ kfree(void *pa)
{ {
struct run *r; struct run *r;
if(((u64)pa % PGSIZE) != 0 || (char*)pa < end || (u64)pa >= PHYSTOP) if(((u64)pa % PGSIZE) != 0 || (char *)pa < end || (u64)pa >= PHYSTOP)
panic("kfree"); panic("kfree");
// Fill with junk to catch dangling refs. // Fill with junk to catch dangling refs.
memset(pa, 1, PGSIZE); memset(pa, 1, PGSIZE);
r = (struct run*)pa; r = (struct run *)pa;
acquire(&kmem.lock); acquire(&kmem.lock);
r->next = kmem.freelist; r->next = kmem.freelist;
@ -77,6 +77,6 @@ kalloc(void)
release(&kmem.lock); release(&kmem.lock);
if(r) if(r)
memset((char*)r, 5, PGSIZE); // fill with junk memset((char *)r, 5, PGSIZE); // fill with junk
return (void*)r; return (void *)r;
} }

41
kernel/log.c
View file

@ -54,7 +54,7 @@ static void commit();
void void
initlog(int dev, struct superblock *sb) initlog(int dev, struct superblock *sb)
{ {
if (sizeof(struct logheader) >= BSIZE) if(sizeof(struct logheader) >= BSIZE)
panic("initlog: too big logheader"); panic("initlog: too big logheader");
initlock(&log.lock, "log"); initlock(&log.lock, "log");
@ -70,8 +70,8 @@ install_trans(int recovering)
{ {
int tail; int tail;
for (tail = 0; tail < log.lh.n; tail++) { for(tail = 0; tail < log.lh.n; tail++) {
struct buf *lbuf = bread(log.dev, log.start+tail+1); // read log block struct buf *lbuf = bread(log.dev, log.start + tail + 1); // read log block
struct buf *dbuf = bread(log.dev, log.lh.block[tail]); // read dst struct buf *dbuf = bread(log.dev, log.lh.block[tail]); // read dst
memmove(dbuf->data, lbuf->data, BSIZE); // copy block to dst memmove(dbuf->data, lbuf->data, BSIZE); // copy block to dst
bwrite(dbuf); // write dst to disk bwrite(dbuf); // write dst to disk
@ -87,10 +87,10 @@ static void
read_head(void) read_head(void)
{ {
struct buf *buf = bread(log.dev, log.start); struct buf *buf = bread(log.dev, log.start);
struct logheader *lh = (struct logheader *) (buf->data); struct logheader *lh = (struct logheader *)(buf->data);
int i; int i;
log.lh.n = lh->n; log.lh.n = lh->n;
for (i = 0; i < log.lh.n; i++) { for(i = 0; i < log.lh.n; i++) {
log.lh.block[i] = lh->block[i]; log.lh.block[i] = lh->block[i];
} }
brelse(buf); brelse(buf);
@ -103,10 +103,10 @@ static void
write_head(void) write_head(void)
{ {
struct buf *buf = bread(log.dev, log.start); struct buf *buf = bread(log.dev, log.start);
struct logheader *hb = (struct logheader *) (buf->data); struct logheader *hb = (struct logheader *)(buf->data);
int i; int i;
hb->n = log.lh.n; hb->n = log.lh.n;
for (i = 0; i < log.lh.n; i++) { for(i = 0; i < log.lh.n; i++) {
hb->block[i] = log.lh.block[i]; hb->block[i] = log.lh.block[i];
} }
bwrite(buf); bwrite(buf);
@ -127,10 +127,10 @@ void
begin_op(void) begin_op(void)
{ {
acquire(&log.lock); acquire(&log.lock);
while(1){ while(1) {
if(log.committing){ if(log.committing) {
sleep(&log, &log.lock); sleep(&log, &log.lock);
} else if(log.lh.n + (log.outstanding+1)*MAXOPBLOCKS > LOGSIZE){ } else if(log.lh.n + (log.outstanding + 1) * MAXOPBLOCKS > LOGSIZE) {
// this op might exhaust log space; wait for commit. // this op might exhaust log space; wait for commit.
sleep(&log, &log.lock); sleep(&log, &log.lock);
} else { } else {
@ -152,7 +152,7 @@ end_op(void)
log.outstanding -= 1; log.outstanding -= 1;
if(log.committing) if(log.committing)
panic("log.committing"); panic("log.committing");
if(log.outstanding == 0){ if(log.outstanding == 0) {
do_commit = 1; do_commit = 1;
log.committing = 1; log.committing = 1;
} else { } else {
@ -163,7 +163,7 @@ end_op(void)
} }
release(&log.lock); release(&log.lock);
if(do_commit){ if(do_commit) {
// call commit w/o holding locks, since not allowed // call commit w/o holding locks, since not allowed
// to sleep with locks. // to sleep with locks.
commit(); commit();
@ -180,8 +180,8 @@ write_log(void)
{ {
int tail; int tail;
for (tail = 0; tail < log.lh.n; tail++) { for(tail = 0; tail < log.lh.n; tail++) {
struct buf *to = bread(log.dev, log.start+tail+1); // log block struct buf *to = bread(log.dev, log.start + tail + 1); // log block
struct buf *from = bread(log.dev, log.lh.block[tail]); // cache block struct buf *from = bread(log.dev, log.lh.block[tail]); // cache block
memmove(to->data, from->data, BSIZE); memmove(to->data, from->data, BSIZE);
bwrite(to); // write the log bwrite(to); // write the log
@ -193,7 +193,7 @@ write_log(void)
static void static void
commit() commit()
{ {
if (log.lh.n > 0) { if(log.lh.n > 0) {
write_log(); // Write modified blocks from cache to log write_log(); // Write modified blocks from cache to log
write_head(); // Write header to disk -- the real commit write_head(); // Write header to disk -- the real commit
install_trans(0); // Now install writes to home locations install_trans(0); // Now install writes to home locations
@ -217,20 +217,19 @@ log_write(struct buf *b)
int i; int i;
acquire(&log.lock); acquire(&log.lock);
if (log.lh.n >= LOGSIZE || log.lh.n >= log.size - 1) if(log.lh.n >= LOGSIZE || log.lh.n >= log.size - 1)
panic("too big a transaction"); panic("too big a transaction");
if (log.outstanding < 1) if(log.outstanding < 1)
panic("log_write outside of trans"); panic("log_write outside of trans");
for (i = 0; i < log.lh.n; i++) { for(i = 0; i < log.lh.n; i++) {
if (log.lh.block[i] == b->blockno) // log absorption if(log.lh.block[i] == b->blockno) // log absorption
break; break;
} }
log.lh.block[i] = b->blockno; log.lh.block[i] = b->blockno;
if (i == log.lh.n) { // Add new block to log? if(i == log.lh.n) { // Add new block to log?
bpin(b); bpin(b);
log.lh.n++; log.lh.n++;
} }
release(&log.lock); release(&log.lock);
} }

2
kernel/main.c
View file

@ -10,7 +10,7 @@ volatile static int started = 0;
void void
main() main()
{ {
if(cpuid() == 0){ if(cpuid() == 0) {
consoleinit(); consoleinit();
printfinit(); printfinit();
printf("\n"); printf("\n");

18
kernel/memlayout.h
View file

@ -27,25 +27,25 @@
// core local interruptor (CLINT), which contains the timer. // core local interruptor (CLINT), which contains the timer.
#define CLINT 0x2000000L #define CLINT 0x2000000L
#define CLINT_MTIMECMP(hartid) (CLINT + 0x4000 + 8*(hartid)) #define CLINT_MTIMECMP(hartid) (CLINT + 0x4000 + 8 * (hartid))
#define CLINT_MTIME (CLINT + 0xBFF8) // cycles since boot. #define CLINT_MTIME (CLINT + 0xBFF8) // cycles since boot.
// qemu puts platform-level interrupt controller (PLIC) here. // qemu puts platform-level interrupt controller (PLIC) here.
#define PLIC 0x0c000000L #define PLIC 0x0c000000L
#define PLIC_PRIORITY (PLIC + 0x0) #define PLIC_PRIORITY (PLIC + 0x0)
#define PLIC_PENDING (PLIC + 0x1000) #define PLIC_PENDING (PLIC + 0x1000)
#define PLIC_MENABLE(hart) (PLIC + 0x2000 + (hart)*0x100) #define PLIC_MENABLE(hart) (PLIC + 0x2000 + (hart) * 0x100)
#define PLIC_SENABLE(hart) (PLIC + 0x2080 + (hart)*0x100) #define PLIC_SENABLE(hart) (PLIC + 0x2080 + (hart) * 0x100)
#define PLIC_MPRIORITY(hart) (PLIC + 0x200000 + (hart)*0x2000) #define PLIC_MPRIORITY(hart) (PLIC + 0x200000 + (hart) * 0x2000)
#define PLIC_SPRIORITY(hart) (PLIC + 0x201000 + (hart)*0x2000) #define PLIC_SPRIORITY(hart) (PLIC + 0x201000 + (hart) * 0x2000)
#define PLIC_MCLAIM(hart) (PLIC + 0x200004 + (hart)*0x2000) #define PLIC_MCLAIM(hart) (PLIC + 0x200004 + (hart) * 0x2000)
#define PLIC_SCLAIM(hart) (PLIC + 0x201004 + (hart)*0x2000) #define PLIC_SCLAIM(hart) (PLIC + 0x201004 + (hart) * 0x2000)
// the kernel expects there to be RAM // the kernel expects there to be RAM
// for use by the kernel and user pages // for use by the kernel and user pages
// from physical address 0x80000000 to PHYSTOP. // from physical address 0x80000000 to PHYSTOP.
#define KERNBASE 0x80000000L #define KERNBASE 0x80000000L
#define PHYSTOP (KERNBASE + 128*1024*1024) #define PHYSTOP (KERNBASE + 128 * 1024 * 1024)
// map the trampoline page to the highest address, // map the trampoline page to the highest address,
// in both user and kernel space. // in both user and kernel space.
@ -53,7 +53,7 @@
// map kernel stacks beneath the trampoline, // map kernel stacks beneath the trampoline,
// each surrounded by invalid guard pages. // each surrounded by invalid guard pages.
#define KSTACK(p) (TRAMPOLINE - ((p)+1)* 2*PGSIZE) #define KSTACK(p) (TRAMPOLINE - ((p) + 1) * 2 * PGSIZE)
// User memory layout. // User memory layout.
// Address zero first: // Address zero first:

4
kernel/param.h
View file

@ -7,7 +7,7 @@
#define ROOTDEV 1 // device number of file system root disk #define ROOTDEV 1 // device number of file system root disk
#define MAXARG 32 // max exec arguments #define MAXARG 32 // max exec arguments
#define MAXOPBLOCKS 10 // max # of blocks any FS op writes #define MAXOPBLOCKS 10 // max # of blocks any FS op writes
#define LOGSIZE (MAXOPBLOCKS*3) // max data blocks in on-disk log #define LOGSIZE (MAXOPBLOCKS * 3) // max data blocks in on-disk log
#define NBUF (MAXOPBLOCKS*3) // size of disk block cache #define NBUF (MAXOPBLOCKS * 3) // size of disk block cache
#define FSSIZE 2000 // size of file system in blocks #define FSSIZE 2000 // size of file system in blocks
#define MAXPATH 128 // maximum file path name #define MAXPATH 128 // maximum file path name

28
kernel/pipe.c
View file

@ -28,7 +28,7 @@ pipealloc(struct file **f0, struct file **f1)
*f0 = *f1 = 0; *f0 = *f1 = 0;
if((*f0 = filealloc()) == 0 || (*f1 = filealloc()) == 0) if((*f0 = filealloc()) == 0 || (*f1 = filealloc()) == 0)
goto bad; goto bad;
if((pi = (struct pipe*)kalloc()) == 0) if((pi = (struct pipe *)kalloc()) == 0)
goto bad; goto bad;
pi->readopen = 1; pi->readopen = 1;
pi->writeopen = 1; pi->writeopen = 1;
@ -45,9 +45,9 @@ pipealloc(struct file **f0, struct file **f1)
(*f1)->pipe = pi; (*f1)->pipe = pi;
return 0; return 0;
bad: bad:
if(pi) if(pi)
kfree((char*)pi); kfree((char *)pi);
if(*f0) if(*f0)
fileclose(*f0); fileclose(*f0);
if(*f1) if(*f1)
@ -59,16 +59,16 @@ void
pipeclose(struct pipe *pi, int writable) pipeclose(struct pipe *pi, int writable)
{ {
acquire(&pi->lock); acquire(&pi->lock);
if(writable){ if(writable) {
pi->writeopen = 0; pi->writeopen = 0;
wakeup(&pi->nread); wakeup(&pi->nread);
} else { } else {
pi->readopen = 0; pi->readopen = 0;
wakeup(&pi->nwrite); wakeup(&pi->nwrite);
} }
if(pi->readopen == 0 && pi->writeopen == 0){ if(pi->readopen == 0 && pi->writeopen == 0) {
release(&pi->lock); release(&pi->lock);
kfree((char*)pi); kfree((char *)pi);
} else } else
release(&pi->lock); release(&pi->lock);
} }
@ -80,12 +80,12 @@ pipewrite(struct pipe *pi, u64 addr, int n)
struct proc *pr = myproc(); struct proc *pr = myproc();
acquire(&pi->lock); acquire(&pi->lock);
while(i < n){ while(i < n) {
if(pi->readopen == 0 || killed(pr)){ if(pi->readopen == 0 || killed(pr)) {
release(&pi->lock); release(&pi->lock);
return -1; return -1;
} }
if(pi->nwrite == pi->nread + PIPESIZE){ //DOC: pipewrite-full if(pi->nwrite == pi->nread + PIPESIZE) { // DOC: pipewrite-full
wakeup(&pi->nread); wakeup(&pi->nread);
sleep(&pi->nwrite, &pi->lock); sleep(&pi->nwrite, &pi->lock);
} else { } else {
@ -110,21 +110,21 @@ piperead(struct pipe *pi, u64 addr, int n)
char ch; char ch;
acquire(&pi->lock); acquire(&pi->lock);
while(pi->nread == pi->nwrite && pi->writeopen){ //DOC: pipe-empty while(pi->nread == pi->nwrite && pi->writeopen) { // DOC: pipe-empty
if(killed(pr)){ if(killed(pr)) {
release(&pi->lock); release(&pi->lock);
return -1; return -1;
} }
sleep(&pi->nread, &pi->lock); //DOC: piperead-sleep sleep(&pi->nread, &pi->lock); // DOC: piperead-sleep
} }
for(i = 0; i < n; i++){ //DOC: piperead-copy for(i = 0; i < n; i++) { // DOC: piperead-copy
if(pi->nread == pi->nwrite) if(pi->nread == pi->nwrite)
break; break;
ch = pi->data[pi->nread++ % PIPESIZE]; ch = pi->data[pi->nread++ % PIPESIZE];
if(copyout(pr->pagetable, addr + i, &ch, 1) == -1) if(copyout(pr->pagetable, addr + i, &ch, 1) == -1)
break; break;
} }
wakeup(&pi->nwrite); //DOC: piperead-wakeup wakeup(&pi->nwrite); // DOC: piperead-wakeup
release(&pi->lock); release(&pi->lock);
return i; return i;
} }

12
kernel/plic.c
View file

@ -12,8 +12,8 @@ void
plicinit(void) plicinit(void)
{ {
// set desired IRQ priorities non-zero (otherwise disabled). // set desired IRQ priorities non-zero (otherwise disabled).
*(u32*)(PLIC + UART0_IRQ*4) = 1; *(u32 *)(PLIC + UART0_IRQ * 4) = 1;
*(u32*)(PLIC + VIRTIO0_IRQ*4) = 1; *(u32 *)(PLIC + VIRTIO0_IRQ * 4) = 1;
} }
void void
@ -23,10 +23,10 @@ plicinithart(void)
// set enable bits for this hart's S-mode // set enable bits for this hart's S-mode
// for the uart and virtio disk. // for the uart and virtio disk.
*(u32*)PLIC_SENABLE(hart) = (1 << UART0_IRQ) | (1 << VIRTIO0_IRQ); *(u32 *)PLIC_SENABLE(hart) = (1 << UART0_IRQ) | (1 << VIRTIO0_IRQ);
// set this hart's S-mode priority threshold to 0. // set this hart's S-mode priority threshold to 0.
*(u32*)PLIC_SPRIORITY(hart) = 0; *(u32 *)PLIC_SPRIORITY(hart) = 0;
} }
// ask the PLIC what interrupt we should serve. // ask the PLIC what interrupt we should serve.
@ -34,7 +34,7 @@ int
plic_claim(void) plic_claim(void)
{ {
int hart = cpuid(); int hart = cpuid();
int irq = *(u32*)PLIC_SCLAIM(hart); int irq = *(u32 *)PLIC_SCLAIM(hart);
return irq; return irq;
} }
@ -43,5 +43,5 @@ void
plic_complete(int irq) plic_complete(int irq)
{ {
int hart = cpuid(); int hart = cpuid();
*(u32*)PLIC_SCLAIM(hart) = irq; *(u32 *)PLIC_SCLAIM(hart) = irq;
} }

12
kernel/printf.c
View file

@ -55,7 +55,7 @@ printptr(u64 x)
int i; int i;
consputc('0'); consputc('0');
consputc('x'); consputc('x');
for (i = 0; i < (sizeof(u64) * 2); i++, x <<= 4) for(i = 0; i < (sizeof(u64) * 2); i++, x <<= 4)
consputc(digits[x >> (sizeof(u64) * 8 - 4)]); consputc(digits[x >> (sizeof(u64) * 8 - 4)]);
} }
@ -71,19 +71,19 @@ printf(char *fmt, ...)
if(locking) if(locking)
acquire(&pr.lock); acquire(&pr.lock);
if (fmt == 0) if(fmt == 0)
panic("null fmt"); panic("null fmt");
va_start(ap, fmt); va_start(ap, fmt);
for(i = 0; (c = fmt[i] & 0xff) != 0; i++){ for(i = 0; (c = fmt[i] & 0xff) != 0; i++) {
if(c != '%'){ if(c != '%') {
consputc(c); consputc(c);
continue; continue;
} }
c = fmt[++i] & 0xff; c = fmt[++i] & 0xff;
if(c == 0) if(c == 0)
break; break;
switch(c){ switch(c) {
case 'd': case 'd':
printint(va_arg(ap, int), 10, 1); printint(va_arg(ap, int), 10, 1);
break; break;
@ -94,7 +94,7 @@ printf(char *fmt, ...)
printptr(va_arg(ap, u64)); printptr(va_arg(ap, u64));
break; break;
case 's': case 's':
if((s = va_arg(ap, char*)) == 0) if((s = va_arg(ap, char *)) == 0)
s = "(null)"; s = "(null)";
for(; *s; s++) for(; *s; s++)
consputc(*s); consputc(*s);

95
kernel/proc.c
View file

@ -38,7 +38,7 @@ proc_mapstacks(pagetable_t kpgtbl)
char *pa = kalloc(); char *pa = kalloc();
if(pa == 0) if(pa == 0)
panic("kalloc"); panic("kalloc");
u64 va = KSTACK((int) (p - proc)); u64 va = KSTACK((int)(p - proc));
kvmmap(kpgtbl, va, (u64)pa, PGSIZE, PTE_R | PTE_W); kvmmap(kpgtbl, va, (u64)pa, PGSIZE, PTE_R | PTE_W);
} }
} }
@ -54,7 +54,7 @@ procinit(void)
for(p = proc; p < &proc[NPROC]; p++) { for(p = proc; p < &proc[NPROC]; p++) {
initlock(&p->lock, "proc"); initlock(&p->lock, "proc");
p->state = UNUSED; p->state = UNUSED;
p->kstack = KSTACK((int) (p - proc)); p->kstack = KSTACK((int)(p - proc));
} }
} }
@ -70,7 +70,7 @@ cpuid()
// Return this CPU's cpu struct. // Return this CPU's cpu struct.
// Interrupts must be disabled. // Interrupts must be disabled.
struct cpu* struct cpu *
mycpu(void) mycpu(void)
{ {
int id = cpuid(); int id = cpuid();
@ -79,7 +79,7 @@ mycpu(void)
} }
// Return the current struct proc *, or zero if none. // Return the current struct proc *, or zero if none.
struct proc* struct proc *
myproc(void) myproc(void)
{ {
push_off(); push_off();
@ -106,7 +106,7 @@ allocpid()
// If found, initialize state required to run in the kernel, // If found, initialize state required to run in the kernel,
// and return with p->lock held. // and return with p->lock held.
// If there are no free procs, or a memory allocation fails, return 0. // If there are no free procs, or a memory allocation fails, return 0.
static struct proc* static struct proc *
allocproc(void) allocproc(void)
{ {
struct proc *p; struct proc *p;
@ -126,7 +126,7 @@ found:
p->state = USED; p->state = USED;
// Allocate a trapframe page. // Allocate a trapframe page.
if((p->trapframe = (struct trapframe *)kalloc()) == 0){ if((p->trapframe = (struct trapframe *)kalloc()) == 0) {
freeproc(p); freeproc(p);
release(&p->lock); release(&p->lock);
return 0; return 0;
@ -134,7 +134,7 @@ found:
// An empty user page table. // An empty user page table.
p->pagetable = proc_pagetable(p); p->pagetable = proc_pagetable(p);
if(p->pagetable == 0){ if(p->pagetable == 0) {
freeproc(p); freeproc(p);
release(&p->lock); release(&p->lock);
return 0; return 0;
@ -156,7 +156,7 @@ static void
freeproc(struct proc *p) freeproc(struct proc *p)
{ {
if(p->trapframe) if(p->trapframe)
kfree((void*)p->trapframe); kfree((void *)p->trapframe);
p->trapframe = 0; p->trapframe = 0;
if(p->pagetable) if(p->pagetable)
proc_freepagetable(p->pagetable, p->sz); proc_freepagetable(p->pagetable, p->sz);
@ -187,16 +187,14 @@ proc_pagetable(struct proc *p)
// at the highest user virtual address. // at the highest user virtual address.
// only the supervisor uses it, on the way // only the supervisor uses it, on the way
// to/from user space, so not PTE_U. // to/from user space, so not PTE_U.
if(mappages(pagetable, TRAMPOLINE, PGSIZE, if(mappages(pagetable, TRAMPOLINE, PGSIZE, (u64)trampoline, PTE_R | PTE_X) < 0) {
(u64)trampoline, PTE_R | PTE_X) < 0){
uvmfree(pagetable, 0); uvmfree(pagetable, 0);
return 0; return 0;
} }
// map the trapframe page just below the trampoline page, for // map the trapframe page just below the trampoline page, for
// trampoline.S. // trampoline.S.
if(mappages(pagetable, TRAPFRAME, PGSIZE, if(mappages(pagetable, TRAPFRAME, PGSIZE, (u64)(p->trapframe), PTE_R | PTE_W) < 0) {
(u64)(p->trapframe), PTE_R | PTE_W) < 0){
uvmunmap(pagetable, TRAMPOLINE, 1, 0); uvmunmap(pagetable, TRAMPOLINE, 1, 0);
uvmfree(pagetable, 0); uvmfree(pagetable, 0);
return 0; return 0;
@ -218,15 +216,10 @@ proc_freepagetable(pagetable_t pagetable, u64 sz)
// a user program that calls exec("/init") // a user program that calls exec("/init")
// assembled from ../user/initcode.S // assembled from ../user/initcode.S
// od -t xC ../user/initcode // od -t xC ../user/initcode
u8 initcode[] = { u8 initcode[]
0x17, 0x05, 0x00, 0x00, 0x13, 0x05, 0x45, 0x02, = { 0x17, 0x05, 0x00, 0x00, 0x13, 0x05, 0x45, 0x02, 0x97, 0x05, 0x00, 0x00, 0x93, 0x85, 0x35, 0x02, 0x93, 0x08,
0x97, 0x05, 0x00, 0x00, 0x93, 0x85, 0x35, 0x02, 0x70, 0x00, 0x73, 0x00, 0x00, 0x00, 0x93, 0x08, 0x20, 0x00, 0x73, 0x00, 0x00, 0x00, 0xef, 0xf0, 0x9f, 0xff,
0x93, 0x08, 0x70, 0x00, 0x73, 0x00, 0x00, 0x00, 0x2f, 0x69, 0x6e, 0x69, 0x74, 0x00, 0x00, 0x24, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
0x93, 0x08, 0x20, 0x00, 0x73, 0x00, 0x00, 0x00,
0xef, 0xf0, 0x9f, 0xff, 0x2f, 0x69, 0x6e, 0x69,
0x74, 0x00, 0x00, 0x24, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00
};
// Set up first user process. // Set up first user process.
void void
@ -263,11 +256,11 @@ growproc(int n)
struct proc *p = myproc(); struct proc *p = myproc();
sz = p->sz; sz = p->sz;
if(n > 0){ if(n > 0) {
if((sz = uvmalloc(p->pagetable, sz, sz + n, PTE_W)) == 0) { if((sz = uvmalloc(p->pagetable, sz, sz + n, PTE_W)) == 0) {
return -1; return -1;
} }
} else if(n < 0){ } else if(n < 0) {
sz = uvmdealloc(p->pagetable, sz, sz + n); sz = uvmdealloc(p->pagetable, sz, sz + n);
} }
p->sz = sz; p->sz = sz;
@ -284,12 +277,12 @@ fork(void)
struct proc *p = myproc(); struct proc *p = myproc();
// Allocate process. // Allocate process.
if((np = allocproc()) == 0){ if((np = allocproc()) == 0) {
return -1; return -1;
} }
// Copy user memory from parent to child. // Copy user memory from parent to child.
if(uvmcopy(p->pagetable, np->pagetable, p->sz) < 0){ if(uvmcopy(p->pagetable, np->pagetable, p->sz) < 0) {
freeproc(np); freeproc(np);
release(&np->lock); release(&np->lock);
return -1; return -1;
@ -332,8 +325,8 @@ reparent(struct proc *p)
{ {
struct proc *pp; struct proc *pp;
for(pp = proc; pp < &proc[NPROC]; pp++){ for(pp = proc; pp < &proc[NPROC]; pp++) {
if(pp->parent == p){ if(pp->parent == p) {
pp->parent = initproc; pp->parent = initproc;
wakeup(initproc); wakeup(initproc);
} }
@ -352,8 +345,8 @@ exit(int status)
panic("init exiting"); panic("init exiting");
// Close all open files. // Close all open files.
for(int fd = 0; fd < NOFILE; fd++){ for(int fd = 0; fd < NOFILE; fd++) {
if(p->ofile[fd]){ if(p->ofile[fd]) {
struct file *f = p->ofile[fd]; struct file *f = p->ofile[fd];
fileclose(f); fileclose(f);
p->ofile[fd] = 0; p->ofile[fd] = 0;
@ -396,20 +389,19 @@ wait(u64 addr)
acquire(&wait_lock); acquire(&wait_lock);
for(;;){ for(;;) {
// Scan through table looking for exited children. // Scan through table looking for exited children.
havekids = 0; havekids = 0;
for(pp = proc; pp < &proc[NPROC]; pp++){ for(pp = proc; pp < &proc[NPROC]; pp++) {
if(pp->parent == p){ if(pp->parent == p) {
// make sure the child isn't still in exit() or swtch(). // make sure the child isn't still in exit() or swtch().
acquire(&pp->lock); acquire(&pp->lock);
havekids = 1; havekids = 1;
if(pp->state == ZOMBIE){ if(pp->state == ZOMBIE) {
// Found one. // Found one.
pid = pp->pid; pid = pp->pid;
if(addr != 0 && copyout(p->pagetable, addr, (char *)&pp->xstate, if(addr != 0 && copyout(p->pagetable, addr, (char *)&pp->xstate, sizeof(pp->xstate)) < 0) {
sizeof(pp->xstate)) < 0) {
release(&pp->lock); release(&pp->lock);
release(&wait_lock); release(&wait_lock);
return -1; return -1;
@ -424,13 +416,13 @@ wait(u64 addr)
} }
// No point waiting if we don't have any children. // No point waiting if we don't have any children.
if(!havekids || killed(p)){ if(!havekids || killed(p)) {
release(&wait_lock); release(&wait_lock);
return -1; return -1;
} }
// Wait for a child to exit. // Wait for a child to exit.
sleep(p, &wait_lock); //DOC: wait-sleep sleep(p, &wait_lock); // DOC: wait-sleep
} }
} }
@ -448,7 +440,7 @@ scheduler(void)
struct cpu *c = mycpu(); struct cpu *c = mycpu();
c->proc = 0; c->proc = 0;
for(;;){ for(;;) {
// Avoid deadlock by ensuring that devices can interrupt. // Avoid deadlock by ensuring that devices can interrupt.
intr_on(); intr_on();
@ -519,7 +511,7 @@ forkret(void)
// Still holding p->lock from scheduler. // Still holding p->lock from scheduler.
release(&myproc()->lock); release(&myproc()->lock);
if (first) { if(first) {
// File system initialization must be run in the context of a // File system initialization must be run in the context of a
// regular process (e.g., because it calls sleep), and thus cannot // regular process (e.g., because it calls sleep), and thus cannot
// be run from main(). // be run from main().
@ -544,7 +536,7 @@ sleep(void *chan, struct spinlock *lk)
// (wakeup locks p->lock), // (wakeup locks p->lock),
// so it's okay to release lk. // so it's okay to release lk.
acquire(&p->lock); //DOC: sleeplock1 acquire(&p->lock); // DOC: sleeplock1
release(lk); release(lk);
// Go to sleep. // Go to sleep.
@ -569,7 +561,7 @@ wakeup(void *chan)
struct proc *p; struct proc *p;
for(p = proc; p < &proc[NPROC]; p++) { for(p = proc; p < &proc[NPROC]; p++) {
if(p != myproc()){ if(p != myproc()) {
acquire(&p->lock); acquire(&p->lock);
if(p->state == SLEEPING && p->chan == chan) { if(p->state == SLEEPING && p->chan == chan) {
p->state = RUNNABLE; p->state = RUNNABLE;
@ -587,11 +579,11 @@ kill(int pid)
{ {
struct proc *p; struct proc *p;
for(p = proc; p < &proc[NPROC]; p++){ for(p = proc; p < &proc[NPROC]; p++) {
acquire(&p->lock); acquire(&p->lock);
if(p->pid == pid){ if(p->pid == pid) {
p->killed = 1; p->killed = 1;
if(p->state == SLEEPING){ if(p->state == SLEEPING) {
// Wake process from sleep(). // Wake process from sleep().
p->state = RUNNABLE; p->state = RUNNABLE;
} }
@ -629,7 +621,7 @@ int
either_copyout(int user_dst, u64 dst, void *src, u64 len) either_copyout(int user_dst, u64 dst, void *src, u64 len)
{ {
struct proc *p = myproc(); struct proc *p = myproc();
if(user_dst){ if(user_dst) {
return copyout(p->pagetable, dst, src, len); return copyout(p->pagetable, dst, src, len);
} else { } else {
memmove((char *)dst, src, len); memmove((char *)dst, src, len);
@ -644,10 +636,10 @@ int
either_copyin(void *dst, int user_src, u64 src, u64 len) either_copyin(void *dst, int user_src, u64 src, u64 len)
{ {
struct proc *p = myproc(); struct proc *p = myproc();
if(user_src){ if(user_src) {
return copyin(p->pagetable, dst, src, len); return copyin(p->pagetable, dst, src, len);
} else { } else {
memmove(dst, (char*)src, len); memmove(dst, (char *)src, len);
return 0; return 0;
} }
} }
@ -659,18 +651,13 @@ void
procdump(void) procdump(void)
{ {
static char *states[] = { static char *states[] = {
[UNUSED] "unused", [UNUSED] "unused", [USED] "used", [SLEEPING] "sleep ", [RUNNABLE] "runble", [RUNNING] "run ", [ZOMBIE] "zombie"
[USED] "used",
[SLEEPING] "sleep ",
[RUNNABLE] "runble",
[RUNNING] "run ",
[ZOMBIE] "zombie"
}; };
struct proc *p; struct proc *p;
char *state; char *state;
printf("\n"); printf("\n");
for(p = proc; p < &proc[NPROC]; p++){ for(p = proc; p < &proc[NPROC]; p++) {
if(p->state == UNUSED) if(p->state == UNUSED)
continue; continue;
if(p->state >= 0 && p->state < NELEM(states) && states[p->state]) if(p->state >= 0 && p->state < NELEM(states) && states[p->state])

4
kernel/ramdisk.c
View file

@ -24,7 +24,7 @@ ramdiskrw(struct buf *b)
{ {
if(!holdingsleep(&b->lock)) if(!holdingsleep(&b->lock))
panic("ramdiskrw: buf not locked"); panic("ramdiskrw: buf not locked");
if((b->flags & (B_VALID|B_DIRTY)) == B_VALID) if((b->flags & (B_VALID | B_DIRTY)) == B_VALID)
panic("ramdiskrw: nothing to do"); panic("ramdiskrw: nothing to do");
if(b->blockno >= FSSIZE) if(b->blockno >= FSSIZE)
@ -33,7 +33,7 @@ ramdiskrw(struct buf *b)
u64 diskaddr = b->blockno * BSIZE; u64 diskaddr = b->blockno * BSIZE;
char *addr = (char *)RAMDISK + diskaddr; char *addr = (char *)RAMDISK + diskaddr;
if(b->flags & B_DIRTY){ if(b->flags & B_DIRTY) {
// write // write
memmove(addr, b->data, BSIZE); memmove(addr, b->data, BSIZE);
b->flags &= ~B_DIRTY; b->flags &= ~B_DIRTY;

78
kernel/riscv.h
View file

@ -5,7 +5,7 @@ static inline u64
r_mhartid() r_mhartid()
{ {
u64 x; u64 x;
asm volatile("csrr %0, mhartid" : "=r" (x) ); asm volatile("csrr %0, mhartid" : "=r"(x));
return x; return x;
} }
@ -21,14 +21,14 @@ static inline u64
r_mstatus() r_mstatus()
{ {
u64 x; u64 x;
asm volatile("csrr %0, mstatus" : "=r" (x) ); asm volatile("csrr %0, mstatus" : "=r"(x));
return x; return x;
} }
static inline void static inline void
w_mstatus(u64 x) w_mstatus(u64 x)
{ {
asm volatile("csrw mstatus, %0" : : "r" (x)); asm volatile("csrw mstatus, %0" : : "r"(x));
} }
// machine exception program counter, holds the // machine exception program counter, holds the
@ -37,7 +37,7 @@ w_mstatus(u64 x)
static inline void static inline void
w_mepc(u64 x) w_mepc(u64 x)
{ {
asm volatile("csrw mepc, %0" : : "r" (x)); asm volatile("csrw mepc, %0" : : "r"(x));
} }
// Supervisor Status Register, sstatus // Supervisor Status Register, sstatus
@ -52,14 +52,14 @@ static inline u64
r_sstatus() r_sstatus()
{ {
u64 x; u64 x;
asm volatile("csrr %0, sstatus" : "=r" (x) ); asm volatile("csrr %0, sstatus" : "=r"(x));
return x; return x;
} }
static inline void static inline void
w_sstatus(u64 x) w_sstatus(u64 x)
{ {
asm volatile("csrw sstatus, %0" : : "r" (x)); asm volatile("csrw sstatus, %0" : : "r"(x));
} }
// Supervisor Interrupt Pending // Supervisor Interrupt Pending
@ -67,14 +67,14 @@ static inline u64
r_sip() r_sip()
{ {
u64 x; u64 x;
asm volatile("csrr %0, sip" : "=r" (x) ); asm volatile("csrr %0, sip" : "=r"(x));
return x; return x;
} }
static inline void static inline void
w_sip(u64 x) w_sip(u64 x)
{ {
asm volatile("csrw sip, %0" : : "r" (x)); asm volatile("csrw sip, %0" : : "r"(x));
} }
// Supervisor Interrupt Enable // Supervisor Interrupt Enable
@ -85,14 +85,14 @@ static inline u64
r_sie() r_sie()
{ {
u64 x; u64 x;
asm volatile("csrr %0, sie" : "=r" (x) ); asm volatile("csrr %0, sie" : "=r"(x));
return x; return x;
} }
static inline void static inline void
w_sie(u64 x) w_sie(u64 x)
{ {
asm volatile("csrw sie, %0" : : "r" (x)); asm volatile("csrw sie, %0" : : "r"(x));
} }
// Machine-mode Interrupt Enable // Machine-mode Interrupt Enable
@ -103,14 +103,14 @@ static inline u64
r_mie() r_mie()
{ {
u64 x; u64 x;
asm volatile("csrr %0, mie" : "=r" (x) ); asm volatile("csrr %0, mie" : "=r"(x));
return x; return x;
} }
static inline void static inline void
w_mie(u64 x) w_mie(u64 x)
{ {
asm volatile("csrw mie, %0" : : "r" (x)); asm volatile("csrw mie, %0" : : "r"(x));
} }
// supervisor exception program counter, holds the // supervisor exception program counter, holds the
@ -119,14 +119,14 @@ w_mie(u64 x)
static inline void static inline void
w_sepc(u64 x) w_sepc(u64 x)
{ {
asm volatile("csrw sepc, %0" : : "r" (x)); asm volatile("csrw sepc, %0" : : "r"(x));
} }
static inline u64 static inline u64
r_sepc() r_sepc()
{ {
u64 x; u64 x;
asm volatile("csrr %0, sepc" : "=r" (x) ); asm volatile("csrr %0, sepc" : "=r"(x));
return x; return x;
} }
@ -135,14 +135,14 @@ static inline u64
r_medeleg() r_medeleg()
{ {
u64 x; u64 x;
asm volatile("csrr %0, medeleg" : "=r" (x) ); asm volatile("csrr %0, medeleg" : "=r"(x));
return x; return x;
} }
static inline void static inline void
w_medeleg(u64 x) w_medeleg(u64 x)
{ {
asm volatile("csrw medeleg, %0" : : "r" (x)); asm volatile("csrw medeleg, %0" : : "r"(x));
} }
// Machine Interrupt Delegation // Machine Interrupt Delegation
@ -150,14 +150,14 @@ static inline u64
r_mideleg() r_mideleg()
{ {
u64 x; u64 x;
asm volatile("csrr %0, mideleg" : "=r" (x) ); asm volatile("csrr %0, mideleg" : "=r"(x));
return x; return x;
} }
static inline void static inline void
w_mideleg(u64 x) w_mideleg(u64 x)
{ {
asm volatile("csrw mideleg, %0" : : "r" (x)); asm volatile("csrw mideleg, %0" : : "r"(x));
} }
// Supervisor Trap-Vector Base Address // Supervisor Trap-Vector Base Address
@ -165,14 +165,14 @@ w_mideleg(u64 x)
static inline void static inline void
w_stvec(u64 x) w_stvec(u64 x)
{ {
asm volatile("csrw stvec, %0" : : "r" (x)); asm volatile("csrw stvec, %0" : : "r"(x));
} }
static inline u64 static inline u64
r_stvec() r_stvec()
{ {
u64 x; u64 x;
asm volatile("csrr %0, stvec" : "=r" (x) ); asm volatile("csrr %0, stvec" : "=r"(x));
return x; return x;
} }
@ -180,20 +180,20 @@ r_stvec()
static inline void static inline void
w_mtvec(u64 x) w_mtvec(u64 x)
{ {
asm volatile("csrw mtvec, %0" : : "r" (x)); asm volatile("csrw mtvec, %0" : : "r"(x));
} }
// Physical Memory Protection // Physical Memory Protection
static inline void static inline void
w_pmpcfg0(u64 x) w_pmpcfg0(u64 x)
{ {
asm volatile("csrw pmpcfg0, %0" : : "r" (x)); asm volatile("csrw pmpcfg0, %0" : : "r"(x));
} }
static inline void static inline void
w_pmpaddr0(u64 x) w_pmpaddr0(u64 x)
{ {
asm volatile("csrw pmpaddr0, %0" : : "r" (x)); asm volatile("csrw pmpaddr0, %0" : : "r"(x));
} }
// use riscv's sv39 page table scheme. // use riscv's sv39 page table scheme.
@ -206,21 +206,21 @@ w_pmpaddr0(u64 x)
static inline void static inline void
w_satp(u64 x) w_satp(u64 x)
{ {
asm volatile("csrw satp, %0" : : "r" (x)); asm volatile("csrw satp, %0" : : "r"(x));
} }
static inline u64 static inline u64
r_satp() r_satp()
{ {
u64 x; u64 x;
asm volatile("csrr %0, satp" : "=r" (x) ); asm volatile("csrr %0, satp" : "=r"(x));
return x; return x;
} }
static inline void static inline void
w_mscratch(u64 x) w_mscratch(u64 x)
{ {
asm volatile("csrw mscratch, %0" : : "r" (x)); asm volatile("csrw mscratch, %0" : : "r"(x));
} }
// Supervisor Trap Cause // Supervisor Trap Cause
@ -228,7 +228,7 @@ static inline u64
r_scause() r_scause()
{ {
u64 x; u64 x;
asm volatile("csrr %0, scause" : "=r" (x) ); asm volatile("csrr %0, scause" : "=r"(x));
return x; return x;
} }
@ -237,7 +237,7 @@ static inline u64
r_stval() r_stval()
{ {
u64 x; u64 x;
asm volatile("csrr %0, stval" : "=r" (x) ); asm volatile("csrr %0, stval" : "=r"(x));
return x; return x;
} }
@ -245,14 +245,14 @@ r_stval()
static inline void static inline void
w_mcounteren(u64 x) w_mcounteren(u64 x)
{ {
asm volatile("csrw mcounteren, %0" : : "r" (x)); asm volatile("csrw mcounteren, %0" : : "r"(x));
} }
static inline u64 static inline u64
r_mcounteren() r_mcounteren()
{ {
u64 x; u64 x;
asm volatile("csrr %0, mcounteren" : "=r" (x) ); asm volatile("csrr %0, mcounteren" : "=r"(x));
return x; return x;
} }
@ -261,7 +261,7 @@ static inline u64
r_time() r_time()
{ {
u64 x; u64 x;
asm volatile("csrr %0, time" : "=r" (x) ); asm volatile("csrr %0, time" : "=r"(x));
return x; return x;
} }
@ -291,7 +291,7 @@ static inline u64
r_sp() r_sp()
{ {
u64 x; u64 x;
asm volatile("mv %0, sp" : "=r" (x) ); asm volatile("mv %0, sp" : "=r"(x));
return x; return x;
} }
@ -301,21 +301,21 @@ static inline u64
r_tp() r_tp()
{ {
u64 x; u64 x;
asm volatile("mv %0, tp" : "=r" (x) ); asm volatile("mv %0, tp" : "=r"(x));
return x; return x;
} }
static inline void static inline void
w_tp(u64 x) w_tp(u64 x)
{ {
asm volatile("mv tp, %0" : : "r" (x)); asm volatile("mv tp, %0" : : "r"(x));
} }
static inline u64 static inline u64
r_ra() r_ra()
{ {
u64 x; u64 x;
asm volatile("mv %0, ra" : "=r" (x) ); asm volatile("mv %0, ra" : "=r"(x));
return x; return x;
} }
@ -335,8 +335,8 @@ typedef u64 *pagetable_t; // 512 PTEs
#define PGSIZE 4096 // bytes per page #define PGSIZE 4096 // bytes per page
#define PGSHIFT 12 // bits of offset within a page #define PGSHIFT 12 // bits of offset within a page
#define PGROUNDUP(sz) (((sz)+PGSIZE-1) & ~(PGSIZE-1)) #define PGROUNDUP(sz) (((sz) + PGSIZE - 1) & ~(PGSIZE - 1))
#define PGROUNDDOWN(a) (((a)) & ~(PGSIZE-1)) #define PGROUNDDOWN(a) (((a)) & ~(PGSIZE - 1))
#define PTE_V (1L << 0) // valid #define PTE_V (1L << 0) // valid
#define PTE_R (1L << 1) #define PTE_R (1L << 1)
@ -353,8 +353,8 @@ typedef u64 *pagetable_t; // 512 PTEs
// extract the three 9-bit page table indices from a virtual address. // extract the three 9-bit page table indices from a virtual address.
#define PXMASK 0x1FF // 9 bits #define PXMASK 0x1FF // 9 bits
#define PXSHIFT(level) (PGSHIFT+(9*(level))) #define PXSHIFT(level) (PGSHIFT + (9 * (level)))
#define PX(level, va) ((((u64) (va)) >> PXSHIFT(level)) & PXMASK) #define PX(level, va) ((((u64)(va)) >> PXSHIFT(level)) & PXMASK)
// one beyond the highest possible virtual address. // one beyond the highest possible virtual address.
// MAXVA is actually one bit less than the max allowed by // MAXVA is actually one bit less than the max allowed by

5
kernel/sleeplock.c
View file

@ -22,7 +22,7 @@ void
acquiresleep(struct sleeplock *lk) acquiresleep(struct sleeplock *lk)
{ {
acquire(&lk->lk); acquire(&lk->lk);
while (lk->locked) { while(lk->locked) {
sleep(lk, &lk->lk); sleep(lk, &lk->lk);
} }
lk->locked = 1; lk->locked = 1;
@ -50,6 +50,3 @@ holdingsleep(struct sleeplock *lk)
release(&lk->lk); release(&lk->lk);
return r; return r;
} }

1
kernel/sleeplock.h
View file

@ -7,4 +7,3 @@ struct sleeplock {
char *name; // Name of lock. char *name; // Name of lock.
int pid; // Process holding lock int pid; // Process holding lock
}; };

1
kernel/spinlock.h
View file

@ -6,4 +6,3 @@ struct spinlock {
char *name; // Name of lock. char *name; // Name of lock.
struct cpu *cpu; // The cpu holding the lock. struct cpu *cpu; // The cpu holding the lock.
}; };

4
kernel/start.c
View file

@ -8,7 +8,7 @@ void main();
void timerinit(); void timerinit();
// entry.S needs one stack per CPU. // entry.S needs one stack per CPU.
__attribute__ ((aligned (16))) char stack0[4096 * NCPU]; __attribute__((aligned(16))) char stack0[4096 * NCPU];
// a scratch area per CPU for machine-mode timer interrupts. // a scratch area per CPU for machine-mode timer interrupts.
u64 timer_scratch[NCPU][5]; u64 timer_scratch[NCPU][5];
@ -67,7 +67,7 @@ timerinit()
// ask the CLINT for a timer interrupt. // ask the CLINT for a timer interrupt.
int interval = 1000000; // cycles; about 1/10th second in qemu. int interval = 1000000; // cycles; about 1/10th second in qemu.
*(u64*)CLINT_MTIMECMP(id) = *(u64*)CLINT_MTIME + interval; *(u64 *)CLINT_MTIMECMP(id) = *(u64 *)CLINT_MTIME + interval;
// prepare information in scratch[] for timervec. // prepare information in scratch[] for timervec.
// scratch[0..2] : space for timervec to save registers. // scratch[0..2] : space for timervec to save registers.

19
kernel/string.c
View file

@ -1,11 +1,11 @@
#include "types.h" #include "types.h"
void* void *
memset(void *dst, int c, u32 n) memset(void *dst, int c, u32 n)
{ {
char *cdst = (char *) dst; char *cdst = (char *)dst;
int i; int i;
for(i = 0; i < n; i++){ for(i = 0; i < n; i++) {
cdst[i] = c; cdst[i] = c;
} }
return dst; return dst;
@ -18,7 +18,7 @@ memcmp(const void *v1, const void *v2, u32 n)
s1 = v1; s1 = v1;
s2 = v2; s2 = v2;
while(n-- > 0){ while(n-- > 0) {
if(*s1 != *s2) if(*s1 != *s2)
return *s1 - *s2; return *s1 - *s2;
s1++, s2++; s1++, s2++;
@ -27,7 +27,7 @@ memcmp(const void *v1, const void *v2, u32 n)
return 0; return 0;
} }
void* void *
memmove(void *dst, const void *src, u32 n) memmove(void *dst, const void *src, u32 n)
{ {
const char *s; const char *s;
@ -38,7 +38,7 @@ memmove(void *dst, const void *src, u32 n)
s = src; s = src;
d = dst; d = dst;
if(s < d && s + n > d){ if(s < d && s + n > d) {
s += n; s += n;
d += n; d += n;
while(n-- > 0) while(n-- > 0)
@ -51,7 +51,7 @@ memmove(void *dst, const void *src, u32 n)
} }
// memcpy exists to placate GCC. Use memmove. // memcpy exists to placate GCC. Use memmove.
void* void *
memcpy(void *dst, const void *src, u32 n) memcpy(void *dst, const void *src, u32 n)
{ {
return memmove(dst, src, n); return memmove(dst, src, n);
@ -67,7 +67,7 @@ strncmp(const char *p, const char *q, u32 n)
return (u8)*p - (u8)*q; return (u8)*p - (u8)*q;
} }
char* char *
strncpy(char *s, const char *t, int n) strncpy(char *s, const char *t, int n)
{ {
char *os; char *os;
@ -81,7 +81,7 @@ strncpy(char *s, const char *t, int n)
} }
// Like strncpy but guaranteed to NUL-terminate. // Like strncpy but guaranteed to NUL-terminate.
char* char *
safestrcpy(char *s, const char *t, int n) safestrcpy(char *s, const char *t, int n)
{ {
char *os; char *os;
@ -104,4 +104,3 @@ strlen(const char *s)
; ;
return n; return n;
} }

34
kernel/syscall.c
View file

@ -12,7 +12,7 @@ int
fetchaddr(u64 addr, u64 *ip) fetchaddr(u64 addr, u64 *ip)
{ {
struct proc *p = myproc(); struct proc *p = myproc();
if(addr >= p->sz || addr+sizeof(u64) > p->sz) // both tests needed, in case of overflow if(addr >= p->sz || addr + sizeof(u64) > p->sz) // both tests needed, in case of overflow
return -1; return -1;
if(copyin(p->pagetable, (char *)ip, addr, sizeof(*ip)) != 0) if(copyin(p->pagetable, (char *)ip, addr, sizeof(*ip)) != 0)
return -1; return -1;
@ -34,7 +34,7 @@ static u64
argraw(int n) argraw(int n)
{ {
struct proc *p = myproc(); struct proc *p = myproc();
switch (n) { switch(n) {
case 0: case 0:
return p->trapframe->a0; return p->trapframe->a0;
case 1: case 1:
@ -105,27 +105,12 @@ extern u64 sys_close(void);
// An array mapping syscall numbers from syscall.h // An array mapping syscall numbers from syscall.h
// to the function that handles the system call. // to the function that handles the system call.
static u64 (*syscalls[])(void) = { static u64 (*syscalls[])(void) = {
[SYS_fork] sys_fork, [SYS_fork] sys_fork, [SYS_exit] sys_exit, [SYS_wait] sys_wait, [SYS_pipe] sys_pipe,
[SYS_exit] sys_exit, [SYS_read] sys_read, [SYS_kill] sys_kill, [SYS_exec] sys_exec, [SYS_fstat] sys_fstat,
[SYS_wait] sys_wait, [SYS_chdir] sys_chdir, [SYS_dup] sys_dup, [SYS_getpid] sys_getpid, [SYS_sbrk] sys_sbrk,
[SYS_pipe] sys_pipe, [SYS_sleep] sys_sleep, [SYS_uptime] sys_uptime, [SYS_open] sys_open, [SYS_write] sys_write,
[SYS_read] sys_read, [SYS_mknod] sys_mknod, [SYS_unlink] sys_unlink, [SYS_link] sys_link, [SYS_mkdir] sys_mkdir,
[SYS_kill] sys_kill, [SYS_close] sys_close,
[SYS_exec] sys_exec,
[SYS_fstat] sys_fstat,
[SYS_chdir] sys_chdir,
[SYS_dup] sys_dup,
[SYS_getpid] sys_getpid,
[SYS_sbrk] sys_sbrk,
[SYS_sleep] sys_sleep,
[SYS_uptime] sys_uptime,
[SYS_open] sys_open,
[SYS_write] sys_write,
[SYS_mknod] sys_mknod,
[SYS_unlink] sys_unlink,
[SYS_link] sys_link,
[SYS_mkdir] sys_mkdir,
[SYS_close] sys_close,
}; };
void void
@ -140,8 +125,7 @@ syscall(void)
// and store its return value in p->trapframe->a0 // and store its return value in p->trapframe->a0
p->trapframe->a0 = syscalls[num](); p->trapframe->a0 = syscalls[num]();
} else { } else {
printf("%d %s: unknown sys call %d\n", printf("%d %s: unknown sys call %d\n", p->pid, p->name, num);
p->pid, p->name, num);
p->trapframe->a0 = -1; p->trapframe->a0 = -1;
} }
} }

75
kernel/sysfile.c
View file

@ -25,7 +25,7 @@ argfd(int n, int *pfd, struct file **pf)
struct file *f; struct file *f;
argint(n, &fd); argint(n, &fd);
if(fd < 0 || fd >= NOFILE || (f=myproc()->ofile[fd]) == 0) if(fd < 0 || fd >= NOFILE || (f = myproc()->ofile[fd]) == 0)
return -1; return -1;
if(pfd) if(pfd)
*pfd = fd; *pfd = fd;
@ -42,8 +42,8 @@ fdalloc(struct file *f)
int fd; int fd;
struct proc *p = myproc(); struct proc *p = myproc();
for(fd = 0; fd < NOFILE; fd++){ for(fd = 0; fd < NOFILE; fd++) {
if(p->ofile[fd] == 0){ if(p->ofile[fd] == 0) {
p->ofile[fd] = f; p->ofile[fd] = f;
return fd; return fd;
} }
@ -59,7 +59,7 @@ sys_dup(void)
if(argfd(0, 0, &f) < 0) if(argfd(0, 0, &f) < 0)
return -1; return -1;
if((fd=fdalloc(f)) < 0) if((fd = fdalloc(f)) < 0)
return -1; return -1;
filedup(f); filedup(f);
return fd; return fd;
@ -130,13 +130,13 @@ sys_link(void)
return -1; return -1;
begin_op(); begin_op();
if((ip = namei(old)) == 0){ if((ip = namei(old)) == 0) {
end_op(); end_op();
return -1; return -1;
} }
ilock(ip); ilock(ip);
if(ip->type == T_DIR){ if(ip->type == T_DIR) {
iunlockput(ip); iunlockput(ip);
end_op(); end_op();
return -1; return -1;
@ -149,7 +149,7 @@ sys_link(void)
if((dp = nameiparent(new, name)) == 0) if((dp = nameiparent(new, name)) == 0)
goto bad; goto bad;
ilock(dp); ilock(dp);
if(dp->dev != ip->dev || dirlink(dp, name, ip->inum) < 0){ if(dp->dev != ip->dev || dirlink(dp, name, ip->inum) < 0) {
iunlockput(dp); iunlockput(dp);
goto bad; goto bad;
} }
@ -176,7 +176,7 @@ isdirempty(struct inode *dp)
int off; int off;
struct dirent de; struct dirent de;
for(off=2*sizeof(de); off<dp->size; off+=sizeof(de)){ for(off = 2 * sizeof(de); off < dp->size; off += sizeof(de)) {
if(readi(dp, 0, (u64)&de, off, sizeof(de)) != sizeof(de)) if(readi(dp, 0, (u64)&de, off, sizeof(de)) != sizeof(de))
panic("isdirempty: readi"); panic("isdirempty: readi");
if(de.inum != 0) if(de.inum != 0)
@ -197,7 +197,7 @@ sys_unlink(void)
return -1; return -1;
begin_op(); begin_op();
if((dp = nameiparent(path, name)) == 0){ if((dp = nameiparent(path, name)) == 0) {
end_op(); end_op();
return -1; return -1;
} }
@ -214,7 +214,7 @@ sys_unlink(void)
if(ip->nlink < 1) if(ip->nlink < 1)
panic("unlink: nlink < 1"); panic("unlink: nlink < 1");
if(ip->type == T_DIR && !isdirempty(ip)){ if(ip->type == T_DIR && !isdirempty(ip)) {
iunlockput(ip); iunlockput(ip);
goto bad; goto bad;
} }
@ -222,7 +222,7 @@ sys_unlink(void)
memset(&de, 0, sizeof(de)); memset(&de, 0, sizeof(de));
if(writei(dp, 0, (u64)&de, off, sizeof(de)) != sizeof(de)) if(writei(dp, 0, (u64)&de, off, sizeof(de)) != sizeof(de))
panic("unlink: writei"); panic("unlink: writei");
if(ip->type == T_DIR){ if(ip->type == T_DIR) {
dp->nlink--; dp->nlink--;
iupdate(dp); iupdate(dp);
} }
@ -242,7 +242,7 @@ bad:
return -1; return -1;
} }
static struct inode* static struct inode *
create(char *path, short type, short major, short minor) create(char *path, short type, short major, short minor)
{ {
struct inode *ip, *dp; struct inode *ip, *dp;
@ -253,7 +253,7 @@ create(char *path, short type, short major, short minor)
ilock(dp); ilock(dp);
if((ip = dirlookup(dp, name, 0)) != 0){ if((ip = dirlookup(dp, name, 0)) != 0) {
iunlockput(dp); iunlockput(dp);
ilock(ip); ilock(ip);
if(type == T_FILE && (ip->type == T_FILE || ip->type == T_DEVICE)) if(type == T_FILE && (ip->type == T_FILE || ip->type == T_DEVICE))
@ -262,7 +262,7 @@ create(char *path, short type, short major, short minor)
return 0; return 0;
} }
if((ip = ialloc(dp->dev, type)) == 0){ if((ip = ialloc(dp->dev, type)) == 0) {
iunlockput(dp); iunlockput(dp);
return 0; return 0;
} }
@ -273,7 +273,7 @@ create(char *path, short type, short major, short minor)
ip->nlink = 1; ip->nlink = 1;
iupdate(ip); iupdate(ip);
if(type == T_DIR){ // Create . and .. entries. if(type == T_DIR) { // Create . and .. entries.
// No ip->nlink++ for ".": avoid cyclic ref count. // No ip->nlink++ for ".": avoid cyclic ref count.
if(dirlink(ip, ".", ip->inum) < 0 || dirlink(ip, "..", dp->inum) < 0) if(dirlink(ip, ".", ip->inum) < 0 || dirlink(ip, "..", dp->inum) < 0)
goto fail; goto fail;
@ -282,7 +282,7 @@ create(char *path, short type, short major, short minor)
if(dirlink(dp, name, ip->inum) < 0) if(dirlink(dp, name, ip->inum) < 0)
goto fail; goto fail;
if(type == T_DIR){ if(type == T_DIR) {
// now that success is guaranteed: // now that success is guaranteed:
dp->nlink++; // for ".." dp->nlink++; // for ".."
iupdate(dp); iupdate(dp);
@ -292,7 +292,7 @@ create(char *path, short type, short major, short minor)
return ip; return ip;
fail: fail:
// something went wrong. de-allocate ip. // something went wrong. de-allocate ip.
ip->nlink = 0; ip->nlink = 0;
iupdate(ip); iupdate(ip);
@ -316,32 +316,32 @@ sys_open(void)
begin_op(); begin_op();
if(omode & O_CREATE){ if(omode & O_CREATE) {
ip = create(path, T_FILE, 0, 0); ip = create(path, T_FILE, 0, 0);
if(ip == 0){ if(ip == 0) {
end_op(); end_op();
return -1; return -1;
} }
} else { } else {
if((ip = namei(path)) == 0){ if((ip = namei(path)) == 0) {
end_op(); end_op();
return -1; return -1;
} }
ilock(ip); ilock(ip);
if(ip->type == T_DIR && omode != O_RDONLY){ if(ip->type == T_DIR && omode != O_RDONLY) {
iunlockput(ip); iunlockput(ip);
end_op(); end_op();
return -1; return -1;
} }
} }
if(ip->type == T_DEVICE && (ip->major < 0 || ip->major >= NDEV)){ if(ip->type == T_DEVICE && (ip->major < 0 || ip->major >= NDEV)) {
iunlockput(ip); iunlockput(ip);
end_op(); end_op();
return -1; return -1;
} }
if((f = filealloc()) == 0 || (fd = fdalloc(f)) < 0){ if((f = filealloc()) == 0 || (fd = fdalloc(f)) < 0) {
if(f) if(f)
fileclose(f); fileclose(f);
iunlockput(ip); iunlockput(ip);
@ -349,7 +349,7 @@ sys_open(void)
return -1; return -1;
} }
if(ip->type == T_DEVICE){ if(ip->type == T_DEVICE) {
f->type = FD_DEVICE; f->type = FD_DEVICE;
f->major = ip->major; f->major = ip->major;
} else { } else {
@ -360,7 +360,7 @@ sys_open(void)
f->readable = !(omode & O_WRONLY); f->readable = !(omode & O_WRONLY);
f->writable = (omode & O_WRONLY) || (omode & O_RDWR); f->writable = (omode & O_WRONLY) || (omode & O_RDWR);
if((omode & O_TRUNC) && ip->type == T_FILE){ if((omode & O_TRUNC) && ip->type == T_FILE) {
itrunc(ip); itrunc(ip);
} }
@ -377,7 +377,7 @@ sys_mkdir(void)
struct inode *ip; struct inode *ip;
begin_op(); begin_op();
if(argstr(0, path, MAXPATH) < 0 || (ip = create(path, T_DIR, 0, 0)) == 0){ if(argstr(0, path, MAXPATH) < 0 || (ip = create(path, T_DIR, 0, 0)) == 0) {
end_op(); end_op();
return -1; return -1;
} }
@ -396,8 +396,7 @@ sys_mknod(void)
begin_op(); begin_op();
argint(1, &major); argint(1, &major);
argint(2, &minor); argint(2, &minor);
if((argstr(0, path, MAXPATH)) < 0 || if((argstr(0, path, MAXPATH)) < 0 || (ip = create(path, T_DEVICE, major, minor)) == 0) {
(ip = create(path, T_DEVICE, major, minor)) == 0){
end_op(); end_op();
return -1; return -1;
} }
@ -414,12 +413,12 @@ sys_chdir(void)
struct proc *p = myproc(); struct proc *p = myproc();
begin_op(); begin_op();
if(argstr(0, path, MAXPATH) < 0 || (ip = namei(path)) == 0){ if(argstr(0, path, MAXPATH) < 0 || (ip = namei(path)) == 0) {
end_op(); end_op();
return -1; return -1;
} }
ilock(ip); ilock(ip);
if(ip->type != T_DIR){ if(ip->type != T_DIR) {
iunlockput(ip); iunlockput(ip);
end_op(); end_op();
return -1; return -1;
@ -443,14 +442,14 @@ sys_exec(void)
return -1; return -1;
} }
memset(argv, 0, sizeof(argv)); memset(argv, 0, sizeof(argv));
for(i=0;; i++){ for(i = 0;; i++) {
if(i >= NELEM(argv)){ if(i >= NELEM(argv)) {
goto bad; goto bad;
} }
if(fetchaddr(uargv+sizeof(u64)*i, (u64*)&uarg) < 0){ if(fetchaddr(uargv + sizeof(u64) * i, (u64 *)&uarg) < 0) {
goto bad; goto bad;
} }
if(uarg == 0){ if(uarg == 0) {
argv[i] = 0; argv[i] = 0;
break; break;
} }
@ -468,7 +467,7 @@ sys_exec(void)
return ret; return ret;
bad: bad:
for(i = 0; i < NELEM(argv) && argv[i] != 0; i++) for(i = 0; i < NELEM(argv) && argv[i] != 0; i++)
kfree(argv[i]); kfree(argv[i]);
return -1; return -1;
@ -486,15 +485,15 @@ sys_pipe(void)
if(pipealloc(&rf, &wf) < 0) if(pipealloc(&rf, &wf) < 0)
return -1; return -1;
fd0 = -1; fd0 = -1;
if((fd0 = fdalloc(rf)) < 0 || (fd1 = fdalloc(wf)) < 0){ if((fd0 = fdalloc(rf)) < 0 || (fd1 = fdalloc(wf)) < 0) {
if(fd0 >= 0) if(fd0 >= 0)
p->ofile[fd0] = 0; p->ofile[fd0] = 0;
fileclose(rf); fileclose(rf);
fileclose(wf); fileclose(wf);
return -1; return -1;
} }
if(copyout(p->pagetable, fdarray, (char*)&fd0, sizeof(fd0)) < 0 || if(copyout(p->pagetable, fdarray, (char *)&fd0, sizeof(fd0)) < 0
copyout(p->pagetable, fdarray+sizeof(fd0), (char *)&fd1, sizeof(fd1)) < 0){ || copyout(p->pagetable, fdarray + sizeof(fd0), (char *)&fd1, sizeof(fd1)) < 0) {
p->ofile[fd0] = 0; p->ofile[fd0] = 0;
p->ofile[fd1] = 0; p->ofile[fd1] = 0;
fileclose(rf); fileclose(rf);

4
kernel/sysproc.c
View file

@ -57,8 +57,8 @@ sys_sleep(void)
argint(0, &n); argint(0, &n);
acquire(&tickslock); acquire(&tickslock);
ticks0 = ticks; ticks0 = ticks;
while(ticks - ticks0 < n){ while(ticks - ticks0 < n) {
if(killed(myproc())){ if(killed(myproc())) {
release(&tickslock); release(&tickslock);
return -1; return -1;
} }

20
kernel/trap.c
View file

@ -50,7 +50,7 @@ usertrap(void)
// save user program counter. // save user program counter.
p->trapframe->epc = r_sepc(); p->trapframe->epc = r_sepc();
if(r_scause() == 8){ if(r_scause() == 8) {
// system call // system call
if(killed(p)) if(killed(p))
@ -65,7 +65,7 @@ usertrap(void)
intr_on(); intr_on();
syscall(); syscall();
} else if((which_dev = devintr()) != 0){ } else if((which_dev = devintr()) != 0) {
// ok // ok
} else { } else {
printf("usertrap(): unexpected scause %p pid=%d\n", r_scause(), p->pid); printf("usertrap(): unexpected scause %p pid=%d\n", r_scause(), p->pid);
@ -144,7 +144,7 @@ kerneltrap()
if(intr_get() != 0) if(intr_get() != 0)
panic("kerneltrap: interrupts enabled"); panic("kerneltrap: interrupts enabled");
if((which_dev = devintr()) == 0){ if((which_dev = devintr()) == 0) {
printf("scause %p\n", scause); printf("scause %p\n", scause);
printf("sepc=%p stval=%p\n", r_sepc(), r_stval()); printf("sepc=%p stval=%p\n", r_sepc(), r_stval());
panic("kerneltrap"); panic("kerneltrap");
@ -179,18 +179,17 @@ devintr()
{ {
u64 scause = r_scause(); u64 scause = r_scause();
if((scause & 0x8000000000000000L) && if((scause & 0x8000000000000000L) && (scause & 0xff) == 9) {
(scause & 0xff) == 9){
// this is a supervisor external interrupt, via PLIC. // this is a supervisor external interrupt, via PLIC.
// irq indicates which device interrupted. // irq indicates which device interrupted.
int irq = plic_claim(); int irq = plic_claim();
if(irq == UART0_IRQ){ if(irq == UART0_IRQ) {
uartintr(); uartintr();
} else if(irq == VIRTIO0_IRQ){ } else if(irq == VIRTIO0_IRQ) {
virtio_disk_intr(); virtio_disk_intr();
} else if(irq){ } else if(irq) {
printf("unexpected interrupt irq=%d\n", irq); printf("unexpected interrupt irq=%d\n", irq);
} }
@ -201,11 +200,11 @@ devintr()
plic_complete(irq); plic_complete(irq);
return 1; return 1;
} else if(scause == 0x8000000000000001L){ } else if(scause == 0x8000000000000001L) {
// software interrupt from a machine-mode timer interrupt, // software interrupt from a machine-mode timer interrupt,
// forwarded by timervec in kernelvec.S. // forwarded by timervec in kernelvec.S.
if(cpuid() == 0){ if(cpuid() == 0) {
clockintr(); clockintr();
} }
@ -218,4 +217,3 @@ devintr()
return 0; return 0;
} }
} }

33
kernel/uart.c
View file

@ -22,18 +22,18 @@
#define RHR 0 // receive holding register (for input bytes) #define RHR 0 // receive holding register (for input bytes)
#define THR 0 // transmit holding register (for output bytes) #define THR 0 // transmit holding register (for output bytes)
#define IER 1 // interrupt enable register #define IER 1 // interrupt enable register
#define IER_RX_ENABLE (1<<0) #define IER_RX_ENABLE (1 << 0)
#define IER_TX_ENABLE (1<<1) #define IER_TX_ENABLE (1 << 1)
#define FCR 2 // FIFO control register #define FCR 2 // FIFO control register
#define FCR_FIFO_ENABLE (1<<0) #define FCR_FIFO_ENABLE (1 << 0)
#define FCR_FIFO_CLEAR (3<<1) // clear the content of the two FIFOs #define FCR_FIFO_CLEAR (3 << 1) // clear the content of the two FIFOs
#define ISR 2 // interrupt status register #define ISR 2 // interrupt status register
#define LCR 3 // line control register #define LCR 3 // line control register
#define LCR_EIGHT_BITS (3<<0) #define LCR_EIGHT_BITS (3 << 0)
#define LCR_BAUD_LATCH (1<<7) // special mode to set baud rate #define LCR_BAUD_LATCH (1 << 7) // special mode to set baud rate
#define LSR 5 // line status register #define LSR 5 // line status register
#define LSR_RX_READY (1<<0) // input is waiting to be read from RHR #define LSR_RX_READY (1 << 0) // input is waiting to be read from RHR
#define LSR_TX_IDLE (1<<5) // THR can accept another character to send #define LSR_TX_IDLE (1 << 5) // THR can accept another character to send
#define ReadReg(reg) (*(Reg(reg))) #define ReadReg(reg) (*(Reg(reg)))
#define WriteReg(reg, v) (*(Reg(reg)) = (v)) #define WriteReg(reg, v) (*(Reg(reg)) = (v))
@ -88,11 +88,11 @@ uartputc(int c)
{ {
acquire(&uart_tx_lock); acquire(&uart_tx_lock);
if(panicked){ if(panicked) {
for(;;) for(;;)
; ;
} }
while(uart_tx_w == uart_tx_r + UART_TX_BUF_SIZE){ while(uart_tx_w == uart_tx_r + UART_TX_BUF_SIZE) {
// buffer is full. // buffer is full.
// wait for uartstart() to open up space in the buffer. // wait for uartstart() to open up space in the buffer.
sleep(&uart_tx_r, &uart_tx_lock); sleep(&uart_tx_r, &uart_tx_lock);
@ -103,7 +103,6 @@ uartputc(int c)
release(&uart_tx_lock); release(&uart_tx_lock);
} }
// alternate version of uartputc() that doesn't // alternate version of uartputc() that doesn't
// use interrupts, for use by kernel printf() and // use interrupts, for use by kernel printf() and
// to echo characters. it spins waiting for the uart's // to echo characters. it spins waiting for the uart's
@ -113,7 +112,7 @@ uartputc_sync(int c)
{ {
push_off(); push_off();
if(panicked){ if(panicked) {
for(;;) for(;;)
; ;
} }
@ -133,13 +132,13 @@ uartputc_sync(int c)
void void
uartstart() uartstart()
{ {
while(1){ while(1) {
if(uart_tx_w == uart_tx_r){ if(uart_tx_w == uart_tx_r) {
// transmit buffer is empty. // transmit buffer is empty.
return; return;
} }
if((ReadReg(LSR) & LSR_TX_IDLE) == 0){ if((ReadReg(LSR) & LSR_TX_IDLE) == 0) {
// the UART transmit holding register is full, // the UART transmit holding register is full,
// so we cannot give it another byte. // so we cannot give it another byte.
// it will interrupt when it's ready for a new byte. // it will interrupt when it's ready for a new byte.
@ -161,7 +160,7 @@ uartstart()
int int
uartgetc(void) uartgetc(void)
{ {
if(ReadReg(LSR) & 0x01){ if(ReadReg(LSR) & 0x01) {
// input data is ready. // input data is ready.
return ReadReg(RHR); return ReadReg(RHR);
} else { } else {
@ -176,7 +175,7 @@ void
uartintr(void) uartintr(void)
{ {
// read and process incoming characters. // read and process incoming characters.
while(1){ while(1) {
int c = uartgetc(); int c = uartgetc();
if(c == -1) if(c == -1)
break; break;

26
kernel/virtio_disk.c
View file

@ -65,10 +65,8 @@ virtio_disk_init(void)
initlock(&disk.vdisk_lock, "virtio_disk"); initlock(&disk.vdisk_lock, "virtio_disk");
if(*R(VIRTIO_MMIO_MAGIC_VALUE) != 0x74726976 || if(*R(VIRTIO_MMIO_MAGIC_VALUE) != 0x74726976 || *R(VIRTIO_MMIO_VERSION) != 2 || *R(VIRTIO_MMIO_DEVICE_ID) != 2
*R(VIRTIO_MMIO_VERSION) != 2 || || *R(VIRTIO_MMIO_VENDOR_ID) != 0x554d4551) {
*R(VIRTIO_MMIO_DEVICE_ID) != 2 ||
*R(VIRTIO_MMIO_VENDOR_ID) != 0x554d4551){
panic("could not find virtio disk"); panic("could not find virtio disk");
} }
@ -156,8 +154,8 @@ virtio_disk_init(void)
static int static int
alloc_desc() alloc_desc()
{ {
for(int i = 0; i < NUM; i++){ for(int i = 0; i < NUM; i++) {
if(disk.free[i]){ if(disk.free[i]) {
disk.free[i] = 0; disk.free[i] = 0;
return i; return i;
} }
@ -185,7 +183,7 @@ free_desc(int i)
static void static void
free_chain(int i) free_chain(int i)
{ {
while(1){ while(1) {
int flag = disk.desc[i].flags; int flag = disk.desc[i].flags;
int nxt = disk.desc[i].next; int nxt = disk.desc[i].next;
free_desc(i); free_desc(i);
@ -201,9 +199,9 @@ free_chain(int i)
static int static int
alloc3_desc(int *idx) alloc3_desc(int *idx)
{ {
for(int i = 0; i < 3; i++){ for(int i = 0; i < 3; i++) {
idx[i] = alloc_desc(); idx[i] = alloc_desc();
if(idx[i] < 0){ if(idx[i] < 0) {
for(int j = 0; j < i; j++) for(int j = 0; j < i; j++)
free_desc(idx[j]); free_desc(idx[j]);
return -1; return -1;
@ -225,7 +223,7 @@ virtio_disk_rw(struct buf *b, int write)
// allocate the three descriptors. // allocate the three descriptors.
int idx[3]; int idx[3];
while(1){ while(1) {
if(alloc3_desc(idx) == 0) { if(alloc3_desc(idx) == 0) {
break; break;
} }
@ -244,12 +242,12 @@ virtio_disk_rw(struct buf *b, int write)
buf0->reserved = 0; buf0->reserved = 0;
buf0->sector = sector; buf0->sector = sector;
disk.desc[idx[0]].addr = (u64) buf0; disk.desc[idx[0]].addr = (u64)buf0;
disk.desc[idx[0]].len = sizeof(struct virtio_blk_req); disk.desc[idx[0]].len = sizeof(struct virtio_blk_req);
disk.desc[idx[0]].flags = VRING_DESC_F_NEXT; disk.desc[idx[0]].flags = VRING_DESC_F_NEXT;
disk.desc[idx[0]].next = idx[1]; disk.desc[idx[0]].next = idx[1];
disk.desc[idx[1]].addr = (u64) b->data; disk.desc[idx[1]].addr = (u64)b->data;
disk.desc[idx[1]].len = BSIZE; disk.desc[idx[1]].len = BSIZE;
if(write) if(write)
disk.desc[idx[1]].flags = 0; // device reads b->data disk.desc[idx[1]].flags = 0; // device reads b->data
@ -259,7 +257,7 @@ virtio_disk_rw(struct buf *b, int write)
disk.desc[idx[1]].next = idx[2]; disk.desc[idx[1]].next = idx[2];
disk.info[idx[0]].status = 0xff; // device writes 0 on success disk.info[idx[0]].status = 0xff; // device writes 0 on success
disk.desc[idx[2]].addr = (u64) &disk.info[idx[0]].status; disk.desc[idx[2]].addr = (u64)&disk.info[idx[0]].status;
disk.desc[idx[2]].len = 1; disk.desc[idx[2]].len = 1;
disk.desc[idx[2]].flags = VRING_DESC_F_WRITE; // device writes the status disk.desc[idx[2]].flags = VRING_DESC_F_WRITE; // device writes the status
disk.desc[idx[2]].next = 0; disk.desc[idx[2]].next = 0;
@ -309,7 +307,7 @@ virtio_disk_intr()
// the device increments disk.used->idx when it // the device increments disk.used->idx when it
// adds an entry to the used ring. // adds an entry to the used ring.
while(disk.used_idx != disk.used->idx){ while(disk.used_idx != disk.used->idx) {
__sync_synchronize(); __sync_synchronize();
int id = disk.used->ring[disk.used_idx % NUM].id; int id = disk.used->ring[disk.used_idx % NUM].id;

60
kernel/vm.c
View file

@ -21,7 +21,7 @@ kvmmake(void)
{ {
pagetable_t kpgtbl; pagetable_t kpgtbl;
kpgtbl = (pagetable_t) kalloc(); kpgtbl = (pagetable_t)kalloc();
memset(kpgtbl, 0, PGSIZE); memset(kpgtbl, 0, PGSIZE);
// uart registers // uart registers
@ -34,10 +34,10 @@ kvmmake(void)
kvmmap(kpgtbl, PLIC, PLIC, 0x400000, PTE_R | PTE_W); kvmmap(kpgtbl, PLIC, PLIC, 0x400000, PTE_R | PTE_W);
// map kernel text executable and read-only. // map kernel text executable and read-only.
kvmmap(kpgtbl, KERNBASE, KERNBASE, (u64)etext-KERNBASE, PTE_R | PTE_X); kvmmap(kpgtbl, KERNBASE, KERNBASE, (u64)etext - KERNBASE, PTE_R | PTE_X);
// map kernel data and the physical RAM we'll make use of. // map kernel data and the physical RAM we'll make use of.
kvmmap(kpgtbl, (u64)etext, (u64)etext, PHYSTOP-(u64)etext, PTE_R | PTE_W); kvmmap(kpgtbl, (u64)etext, (u64)etext, PHYSTOP - (u64)etext, PTE_R | PTE_W);
// map the trampoline for trap entry/exit to // map the trampoline for trap entry/exit to
// the highest virtual address in the kernel. // the highest virtual address in the kernel.
@ -93,7 +93,7 @@ walk(pagetable_t pagetable, u64 va, int alloc)
if(*pte & PTE_V) { if(*pte & PTE_V) {
pagetable = (pagetable_t)PTE2PA(*pte); pagetable = (pagetable_t)PTE2PA(*pte);
} else { } else {
if(!alloc || (pagetable = (pde_t*)kalloc()) == 0) if(!alloc || (pagetable = (pde_t *)kalloc()) == 0)
return 0; return 0;
memset(pagetable, 0, PGSIZE); memset(pagetable, 0, PGSIZE);
*pte = PA2PTE(pagetable) | PTE_V; *pte = PA2PTE(pagetable) | PTE_V;
@ -150,7 +150,7 @@ mappages(pagetable_t pagetable, u64 va, u64 size, u64 pa, int perm)
a = PGROUNDDOWN(va); a = PGROUNDDOWN(va);
last = PGROUNDDOWN(va + size - 1); last = PGROUNDDOWN(va + size - 1);
for(;;){ for(;;) {
if((pte = walk(pagetable, a, 1)) == 0) if((pte = walk(pagetable, a, 1)) == 0)
return -1; return -1;
if(*pte & PTE_V) if(*pte & PTE_V)
@ -176,16 +176,16 @@ uvmunmap(pagetable_t pagetable, u64 va, u64 npages, int do_free)
if((va % PGSIZE) != 0) if((va % PGSIZE) != 0)
panic("uvmunmap: not aligned"); panic("uvmunmap: not aligned");
for(a = va; a < va + npages*PGSIZE; a += PGSIZE){ for(a = va; a < va + npages * PGSIZE; a += PGSIZE) {
if((pte = walk(pagetable, a, 0)) == 0) if((pte = walk(pagetable, a, 0)) == 0)
panic("uvmunmap: walk"); panic("uvmunmap: walk");
if((*pte & PTE_V) == 0) if((*pte & PTE_V) == 0)
panic("uvmunmap: not mapped"); panic("uvmunmap: not mapped");
if(PTE_FLAGS(*pte) == PTE_V) if(PTE_FLAGS(*pte) == PTE_V)
panic("uvmunmap: not a leaf"); panic("uvmunmap: not a leaf");
if(do_free){ if(do_free) {
u64 pa = PTE2PA(*pte); u64 pa = PTE2PA(*pte);
kfree((void*)pa); kfree((void *)pa);
} }
*pte = 0; *pte = 0;
} }
@ -197,7 +197,7 @@ pagetable_t
uvmcreate() uvmcreate()
{ {
pagetable_t pagetable; pagetable_t pagetable;
pagetable = (pagetable_t) kalloc(); pagetable = (pagetable_t)kalloc();
if(pagetable == 0) if(pagetable == 0)
return 0; return 0;
memset(pagetable, 0, PGSIZE); memset(pagetable, 0, PGSIZE);
@ -216,7 +216,7 @@ uvmfirst(pagetable_t pagetable, u8 *src, u32 sz)
panic("uvmfirst: more than a page"); panic("uvmfirst: more than a page");
mem = kalloc(); mem = kalloc();
memset(mem, 0, PGSIZE); memset(mem, 0, PGSIZE);
mappages(pagetable, 0, PGSIZE, (u64)mem, PTE_W|PTE_R|PTE_X|PTE_U); mappages(pagetable, 0, PGSIZE, (u64)mem, PTE_W | PTE_R | PTE_X | PTE_U);
memmove(mem, src, sz); memmove(mem, src, sz);
} }
@ -232,14 +232,14 @@ uvmalloc(pagetable_t pagetable, u64 oldsz, u64 newsz, int xperm)
return oldsz; return oldsz;
oldsz = PGROUNDUP(oldsz); oldsz = PGROUNDUP(oldsz);
for(a = oldsz; a < newsz; a += PGSIZE){ for(a = oldsz; a < newsz; a += PGSIZE) {
mem = kalloc(); mem = kalloc();
if(mem == 0){ if(mem == 0) {
uvmdealloc(pagetable, a, oldsz); uvmdealloc(pagetable, a, oldsz);
return 0; return 0;
} }
memset(mem, 0, PGSIZE); memset(mem, 0, PGSIZE);
if(mappages(pagetable, a, PGSIZE, (u64)mem, PTE_R|PTE_U|xperm) != 0){ if(mappages(pagetable, a, PGSIZE, (u64)mem, PTE_R | PTE_U | xperm) != 0) {
kfree(mem); kfree(mem);
uvmdealloc(pagetable, a, oldsz); uvmdealloc(pagetable, a, oldsz);
return 0; return 0;
@ -258,7 +258,7 @@ uvmdealloc(pagetable_t pagetable, u64 oldsz, u64 newsz)
if(newsz >= oldsz) if(newsz >= oldsz)
return oldsz; return oldsz;
if(PGROUNDUP(newsz) < PGROUNDUP(oldsz)){ if(PGROUNDUP(newsz) < PGROUNDUP(oldsz)) {
int npages = (PGROUNDUP(oldsz) - PGROUNDUP(newsz)) / PGSIZE; int npages = (PGROUNDUP(oldsz) - PGROUNDUP(newsz)) / PGSIZE;
uvmunmap(pagetable, PGROUNDUP(newsz), npages, 1); uvmunmap(pagetable, PGROUNDUP(newsz), npages, 1);
} }
@ -272,18 +272,18 @@ void
freewalk(pagetable_t pagetable) freewalk(pagetable_t pagetable)
{ {
// there are 2^9 = 512 PTEs in a page table. // there are 2^9 = 512 PTEs in a page table.
for(int i = 0; i < 512; i++){ for(int i = 0; i < 512; i++) {
pte_t pte = pagetable[i]; pte_t pte = pagetable[i];
if((pte & PTE_V) && (pte & (PTE_R|PTE_W|PTE_X)) == 0){ if((pte & PTE_V) && (pte & (PTE_R | PTE_W | PTE_X)) == 0) {
// this PTE points to a lower-level page table. // this PTE points to a lower-level page table.
u64 child = PTE2PA(pte); u64 child = PTE2PA(pte);
freewalk((pagetable_t)child); freewalk((pagetable_t)child);
pagetable[i] = 0; pagetable[i] = 0;
} else if(pte & PTE_V){ } else if(pte & PTE_V) {
panic("freewalk: leaf"); panic("freewalk: leaf");
} }
} }
kfree((void*)pagetable); kfree((void *)pagetable);
} }
// Free user memory pages, // Free user memory pages,
@ -292,7 +292,7 @@ void
uvmfree(pagetable_t pagetable, u64 sz) uvmfree(pagetable_t pagetable, u64 sz)
{ {
if(sz > 0) if(sz > 0)
uvmunmap(pagetable, 0, PGROUNDUP(sz)/PGSIZE, 1); uvmunmap(pagetable, 0, PGROUNDUP(sz) / PGSIZE, 1);
freewalk(pagetable); freewalk(pagetable);
} }
@ -310,7 +310,7 @@ uvmcopy(pagetable_t old, pagetable_t new, u64 sz)
u32 flags; u32 flags;
char *mem; char *mem;
for(i = 0; i < sz; i += PGSIZE){ for(i = 0; i < sz; i += PGSIZE) {
if((pte = walk(old, i, 0)) == 0) if((pte = walk(old, i, 0)) == 0)
panic("uvmcopy: pte should exist"); panic("uvmcopy: pte should exist");
if((*pte & PTE_V) == 0) if((*pte & PTE_V) == 0)
@ -319,15 +319,15 @@ uvmcopy(pagetable_t old, pagetable_t new, u64 sz)
flags = PTE_FLAGS(*pte); flags = PTE_FLAGS(*pte);
if((mem = kalloc()) == 0) if((mem = kalloc()) == 0)
goto err; goto err;
memmove(mem, (char*)pa, PGSIZE); memmove(mem, (char *)pa, PGSIZE);
if(mappages(new, i, PGSIZE, (u64)mem, flags) != 0){ if(mappages(new, i, PGSIZE, (u64)mem, flags) != 0) {
kfree(mem); kfree(mem);
goto err; goto err;
} }
} }
return 0; return 0;
err: err:
uvmunmap(new, 0, i / PGSIZE, 1); uvmunmap(new, 0, i / PGSIZE, 1);
return -1; return -1;
} }
@ -353,7 +353,7 @@ copyout(pagetable_t pagetable, u64 dstva, char *src, u64 len)
{ {
u64 n, va0, pa0; u64 n, va0, pa0;
while(len > 0){ while(len > 0) {
va0 = PGROUNDDOWN(dstva); va0 = PGROUNDDOWN(dstva);
pa0 = walkaddr(pagetable, va0); pa0 = walkaddr(pagetable, va0);
if(pa0 == 0) if(pa0 == 0)
@ -378,7 +378,7 @@ copyin(pagetable_t pagetable, char *dst, u64 srcva, u64 len)
{ {
u64 n, va0, pa0; u64 n, va0, pa0;
while(len > 0){ while(len > 0) {
va0 = PGROUNDDOWN(srcva); va0 = PGROUNDDOWN(srcva);
pa0 = walkaddr(pagetable, va0); pa0 = walkaddr(pagetable, va0);
if(pa0 == 0) if(pa0 == 0)
@ -405,7 +405,7 @@ copyinstr(pagetable_t pagetable, char *dst, u64 srcva, u64 max)
u64 n, va0, pa0; u64 n, va0, pa0;
int got_null = 0; int got_null = 0;
while(got_null == 0 && max > 0){ while(got_null == 0 && max > 0) {
va0 = PGROUNDDOWN(srcva); va0 = PGROUNDDOWN(srcva);
pa0 = walkaddr(pagetable, va0); pa0 = walkaddr(pagetable, va0);
if(pa0 == 0) if(pa0 == 0)
@ -414,9 +414,9 @@ copyinstr(pagetable_t pagetable, char *dst, u64 srcva, u64 max)
if(n > max) if(n > max)
n = max; n = max;
char *p = (char *) (pa0 + (srcva - va0)); char *p = (char *)(pa0 + (srcva - va0));
while(n > 0){ while(n > 0) {
if(*p == '\0'){ if(*p == '\0') {
*dst = '\0'; *dst = '\0';
got_null = 1; got_null = 1;
break; break;
@ -431,7 +431,7 @@ copyinstr(pagetable_t pagetable, char *dst, u64 srcva, u64 max)
srcva = va0 + PGSIZE; srcva = va0 + PGSIZE;
} }
if(got_null){ if(got_null) {
return 0; return 0;
} else { } else {
return -1; return -1;

63
mkfs/mkfs.c
View file

@ -12,7 +12,12 @@
#include "kernel/param.h" #include "kernel/param.h"
#ifndef static_assert #ifndef static_assert
#define static_assert(a, b) do { switch (0) case 0: case (a): ; } while (0) #define static_assert(a, b) \
do { \
switch(0) \
case 0: \
case(a):; \
} while(0)
#endif #endif
#define NINODES 200 #define NINODES 200
@ -20,7 +25,7 @@
// Disk layout: // Disk layout:
// [ boot block | sb block | log | inode blocks | free bit map | data blocks ] // [ boot block | sb block | log | inode blocks | free bit map | data blocks ]
int nbitmap = FSSIZE/(BSIZE*8) + 1; int nbitmap = FSSIZE / (BSIZE * 8) + 1;
int ninodeblocks = NINODES / IPB + 1; int ninodeblocks = NINODES / IPB + 1;
int nlog = LOGSIZE; int nlog = LOGSIZE;
int nmeta; // Number of meta blocks (boot, sb, nlog, inode, bitmap) int nmeta; // Number of meta blocks (boot, sb, nlog, inode, bitmap)
@ -32,10 +37,9 @@ char zeroes[BSIZE];
uint freeinode = 1; uint freeinode = 1;
uint freeblock; uint freeblock;
void balloc(int); void balloc(int);
void wsect(uint, void*); void wsect(uint, void *);
void winode(uint, struct dinode*); void winode(uint, struct dinode *);
void rinode(uint inum, struct dinode *ip); void rinode(uint inum, struct dinode *ip);
void rsect(uint sec, void *buf); void rsect(uint sec, void *buf);
uint ialloc(ushort type); uint ialloc(ushort type);
@ -47,7 +51,7 @@ ushort
xshort(ushort x) xshort(ushort x)
{ {
ushort y; ushort y;
u8 *a = (u8*)&y; u8 *a = (u8 *)&y;
a[0] = x; a[0] = x;
a[1] = x >> 8; a[1] = x >> 8;
return y; return y;
@ -57,7 +61,7 @@ uint
xint(uint x) xint(uint x)
{ {
uint y; uint y;
u8 *a = (u8*)&y; u8 *a = (u8 *)&y;
a[0] = x; a[0] = x;
a[1] = x >> 8; a[1] = x >> 8;
a[2] = x >> 16; a[2] = x >> 16;
@ -74,10 +78,9 @@ main(int argc, char *argv[])
char buf[BSIZE]; char buf[BSIZE];
struct dinode din; struct dinode din;
static_assert(sizeof(int) == 4, "Integers must be 4 bytes!"); static_assert(sizeof(int) == 4, "Integers must be 4 bytes!");
if(argc < 2){ if(argc < 2) {
fprintf(stderr, "Usage: mkfs fs.img files...\n"); fprintf(stderr, "Usage: mkfs fs.img files...\n");
exit(1); exit(1);
} }
@ -85,7 +88,7 @@ main(int argc, char *argv[])
assert((BSIZE % sizeof(struct dinode)) == 0); assert((BSIZE % sizeof(struct dinode)) == 0);
assert((BSIZE % sizeof(struct dirent)) == 0); assert((BSIZE % sizeof(struct dirent)) == 0);
fsfd = open(argv[1], O_RDWR|O_CREAT|O_TRUNC, 0666); fsfd = open(argv[1], O_RDWR | O_CREAT | O_TRUNC, 0666);
if(fsfd < 0) if(fsfd < 0)
die(argv[1]); die(argv[1]);
@ -99,11 +102,11 @@ main(int argc, char *argv[])
sb.ninodes = xint(NINODES); sb.ninodes = xint(NINODES);
sb.nlog = xint(nlog); sb.nlog = xint(nlog);
sb.logstart = xint(2); sb.logstart = xint(2);
sb.inodestart = xint(2+nlog); sb.inodestart = xint(2 + nlog);
sb.bmapstart = xint(2+nlog+ninodeblocks); sb.bmapstart = xint(2 + nlog + ninodeblocks);
printf("nmeta %d (boot, super, log blocks %u inode blocks %u, bitmap blocks %u) blocks %d total %d\n", printf("nmeta %d (boot, super, log blocks %u inode blocks %u, bitmap blocks %u) blocks %d total %d\n", nmeta, nlog,
nmeta, nlog, ninodeblocks, nbitmap, nblocks, FSSIZE); ninodeblocks, nbitmap, nblocks, FSSIZE);
freeblock = nmeta; // the first free block that we can allocate freeblock = nmeta; // the first free block that we can allocate
@ -127,7 +130,7 @@ main(int argc, char *argv[])
strcpy(de.name, ".."); strcpy(de.name, "..");
iappend(rootino, &de, sizeof(de)); iappend(rootino, &de, sizeof(de));
for(i = 2; i < argc; i++){ for(i = 2; i < argc; i++) {
// get rid of "user/" // get rid of "user/"
char *shortname; char *shortname;
if(strncmp(argv[i], "user/", 5) == 0) if(strncmp(argv[i], "user/", 5) == 0)
@ -163,7 +166,7 @@ main(int argc, char *argv[])
// fix size of root inode dir // fix size of root inode dir
rinode(rootino, &din); rinode(rootino, &din);
off = xint(din.size); off = xint(din.size);
off = ((off/BSIZE) + 1) * BSIZE; off = ((off / BSIZE) + 1) * BSIZE;
din.size = xint(off); din.size = xint(off);
winode(rootino, &din); winode(rootino, &din);
@ -190,7 +193,7 @@ winode(uint inum, struct dinode *ip)
bn = IBLOCK(inum, sb); bn = IBLOCK(inum, sb);
rsect(bn, buf); rsect(bn, buf);
dip = ((struct dinode*)buf) + (inum % IPB); dip = ((struct dinode *)buf) + (inum % IPB);
*dip = *ip; *dip = *ip;
wsect(bn, buf); wsect(bn, buf);
} }
@ -204,7 +207,7 @@ rinode(uint inum, struct dinode *ip)
bn = IBLOCK(inum, sb); bn = IBLOCK(inum, sb);
rsect(bn, buf); rsect(bn, buf);
dip = ((struct dinode*)buf) + (inum % IPB); dip = ((struct dinode *)buf) + (inum % IPB);
*ip = *dip; *ip = *dip;
} }
@ -238,10 +241,10 @@ balloc(int used)
int i; int i;
printf("balloc: first %d blocks have been allocated\n", used); printf("balloc: first %d blocks have been allocated\n", used);
assert(used < BSIZE*8); assert(used < BSIZE * 8);
bzero(buf, BSIZE); bzero(buf, BSIZE);
for(i = 0; i < used; i++){ for(i = 0; i < used; i++) {
buf[i/8] = buf[i/8] | (0x1 << (i%8)); buf[i / 8] = buf[i / 8] | (0x1 << (i % 8));
} }
printf("balloc: write bitmap block at sector %d\n", sb.bmapstart); printf("balloc: write bitmap block at sector %d\n", sb.bmapstart);
wsect(sb.bmapstart, buf); wsect(sb.bmapstart, buf);
@ -252,7 +255,7 @@ balloc(int used)
void void
iappend(uint inum, void *xp, int n) iappend(uint inum, void *xp, int n)
{ {
char *p = (char*)xp; char *p = (char *)xp;
uint fbn, off, n1; uint fbn, off, n1;
struct dinode din; struct dinode din;
char buf[BSIZE]; char buf[BSIZE];
@ -262,24 +265,24 @@ iappend(uint inum, void *xp, int n)
rinode(inum, &din); rinode(inum, &din);
off = xint(din.size); off = xint(din.size);
// printf("append inum %d at off %d sz %d\n", inum, off, n); // printf("append inum %d at off %d sz %d\n", inum, off, n);
while(n > 0){ while(n > 0) {
fbn = off / BSIZE; fbn = off / BSIZE;
assert(fbn < MAXFILE); assert(fbn < MAXFILE);
if(fbn < NDIRECT){ if(fbn < NDIRECT) {
if(xint(din.addrs[fbn]) == 0){ if(xint(din.addrs[fbn]) == 0) {
din.addrs[fbn] = xint(freeblock++); din.addrs[fbn] = xint(freeblock++);
} }
x = xint(din.addrs[fbn]); x = xint(din.addrs[fbn]);
} else { } else {
if(xint(din.addrs[NDIRECT]) == 0){ if(xint(din.addrs[NDIRECT]) == 0) {
din.addrs[NDIRECT] = xint(freeblock++); din.addrs[NDIRECT] = xint(freeblock++);
} }
rsect(xint(din.addrs[NDIRECT]), (char*)indirect); rsect(xint(din.addrs[NDIRECT]), (char *)indirect);
if(indirect[fbn - NDIRECT] == 0){ if(indirect[fbn - NDIRECT] == 0) {
indirect[fbn - NDIRECT] = xint(freeblock++); indirect[fbn - NDIRECT] = xint(freeblock++);
wsect(xint(din.addrs[NDIRECT]), (char*)indirect); wsect(xint(din.addrs[NDIRECT]), (char *)indirect);
} }
x = xint(indirect[fbn-NDIRECT]); x = xint(indirect[fbn - NDIRECT]);
} }
n1 = min(n, (fbn + 1) * BSIZE - off); n1 = min(n, (fbn + 1) * BSIZE - off);
rsect(x, buf); rsect(x, buf);

10
user/cat.c
View file

@ -10,12 +10,12 @@ cat(int fd)
int n; int n;
while((n = read(fd, buf, sizeof(buf))) > 0) { while((n = read(fd, buf, sizeof(buf))) > 0) {
if (write(1, buf, n) != n) { if(write(1, buf, n) != n) {
fprintf(2, "cat: write error\n"); fprintf(2, "cat: write error\n");
exit(1); exit(1);
} }
} }
if(n < 0){ if(n < 0) {
fprintf(2, "cat: read error\n"); fprintf(2, "cat: read error\n");
exit(1); exit(1);
} }
@ -26,13 +26,13 @@ main(int argc, char *argv[])
{ {
int fd, i; int fd, i;
if(argc <= 1){ if(argc <= 1) {
cat(0); cat(0);
exit(0); exit(0);
} }
for(i = 1; i < argc; i++){ for(i = 1; i < argc; i++) {
if((fd = open(argv[i], 0)) < 0){ if((fd = open(argv[i], 0)) < 0) {
fprintf(2, "cat: cannot open %s\n", argv[i]); fprintf(2, "cat: cannot open %s\n", argv[i]);
exit(1); exit(1);
} }

4
user/echo.c
View file

@ -7,9 +7,9 @@ main(int argc, char *argv[])
{ {
int i; int i;
for(i = 1; i < argc; i++){ for(i = 1; i < argc; i++) {
write(1, argv[i], strlen(argv[i])); write(1, argv[i], strlen(argv[i]));
if(i + 1 < argc){ if(i + 1 < argc) {
write(1, " ", 1); write(1, " ", 1);
} else { } else {
write(1, "\n", 1); write(1, "\n", 1);

10
user/forktest.c
View file

@ -20,7 +20,7 @@ forktest(void)
print("fork test\n"); print("fork test\n");
for(n=0; n<N; n++){ for(n = 0; n < N; n++) {
pid = fork(); pid = fork();
if(pid < 0) if(pid < 0)
break; break;
@ -28,19 +28,19 @@ forktest(void)
exit(0); exit(0);
} }
if(n == N){ if(n == N) {
print("fork claimed to work N times!\n"); print("fork claimed to work N times!\n");
exit(1); exit(1);
} }
for(; n > 0; n--){ for(; n > 0; n--) {
if(wait(0) < 0){ if(wait(0) < 0) {
print("wait stopped early\n"); print("wait stopped early\n");
exit(1); exit(1);
} }
} }
if(wait(0) != -1){ if(wait(0) != -1) {
print("wait got too many\n"); print("wait got too many\n");
exit(1); exit(1);
} }

49
user/grep.c
View file

@ -5,7 +5,7 @@
#include "user/user.h" #include "user/user.h"
char buf[1024]; char buf[1024];
int match(char*, char*); int match(char *, char *);
void void
grep(char *pattern, int fd) grep(char *pattern, int fd)
@ -14,19 +14,19 @@ grep(char *pattern, int fd)
char *p, *q; char *p, *q;
m = 0; m = 0;
while((n = read(fd, buf+m, sizeof(buf)-m-1)) > 0){ while((n = read(fd, buf + m, sizeof(buf) - m - 1)) > 0) {
m += n; m += n;
buf[m] = '\0'; buf[m] = '\0';
p = buf; p = buf;
while((q = strchr(p, '\n')) != 0){ while((q = strchr(p, '\n')) != 0) {
*q = 0; *q = 0;
if(match(pattern, p)){ if(match(pattern, p)) {
*q = '\n'; *q = '\n';
write(1, p, q+1 - p); write(1, p, q + 1 - p);
} }
p = q+1; p = q + 1;
} }
if(m > 0){ if(m > 0) {
m -= p - buf; m -= p - buf;
memmove(buf, p, m); memmove(buf, p, m);
} }
@ -39,19 +39,19 @@ main(int argc, char *argv[])
int fd, i; int fd, i;
char *pattern; char *pattern;
if(argc <= 1){ if(argc <= 1) {
fprintf(2, "usage: grep pattern [file ...]\n"); fprintf(2, "usage: grep pattern [file ...]\n");
exit(1); exit(1);
} }
pattern = argv[1]; pattern = argv[1];
if(argc <= 2){ if(argc <= 2) {
grep(pattern, 0); grep(pattern, 0);
exit(0); exit(0);
} }
for(i = 2; i < argc; i++){ for(i = 2; i < argc; i++) {
if((fd = open(argv[i], 0)) < 0){ if((fd = open(argv[i], 0)) < 0) {
printf("grep: cannot open %s\n", argv[i]); printf("grep: cannot open %s\n", argv[i]);
exit(1); exit(1);
} }
@ -65,42 +65,43 @@ main(int argc, char *argv[])
// The Practice of Programming, Chapter 9, or // The Practice of Programming, Chapter 9, or
// https://www.cs.princeton.edu/courses/archive/spr09/cos333/beautiful.html // https://www.cs.princeton.edu/courses/archive/spr09/cos333/beautiful.html
int matchhere(char*, char*); int matchhere(char *, char *);
int matchstar(int, char*, char*); int matchstar(int, char *, char *);
int int
match(char *re, char *text) match(char *re, char *text)
{ {
if(re[0] == '^') if(re[0] == '^')
return matchhere(re+1, text); return matchhere(re + 1, text);
do{ // must look at empty string do { // must look at empty string
if(matchhere(re, text)) if(matchhere(re, text))
return 1; return 1;
}while(*text++ != '\0'); } while(*text++ != '\0');
return 0; return 0;
} }
// matchhere: search for re at beginning of text // matchhere: search for re at beginning of text
int matchhere(char *re, char *text) int
matchhere(char *re, char *text)
{ {
if(re[0] == '\0') if(re[0] == '\0')
return 1; return 1;
if(re[1] == '*') if(re[1] == '*')
return matchstar(re[0], re+2, text); return matchstar(re[0], re + 2, text);
if(re[0] == '$' && re[1] == '\0') if(re[0] == '$' && re[1] == '\0')
return *text == '\0'; return *text == '\0';
if(*text!='\0' && (re[0]=='.' || re[0]==*text)) if(*text != '\0' && (re[0] == '.' || re[0] == *text))
return matchhere(re+1, text+1); return matchhere(re + 1, text + 1);
return 0; return 0;
} }
// matchstar: search for c*re at beginning of text // matchstar: search for c*re at beginning of text
int matchstar(int c, char *re, char *text) int
matchstar(int c, char *re, char *text)
{ {
do{ // a * matches zero or more instances do { // a * matches zero or more instances
if(matchhere(re, text)) if(matchhere(re, text))
return 1; return 1;
}while(*text!='\0' && (*text++==c || c=='.')); } while(*text != '\0' && (*text++ == c || c == '.'));
return 0; return 0;
} }

154
user/grind.c
View file

@ -16,7 +16,7 @@
int int
do_rand(unsigned long *ctx) do_rand(unsigned long *ctx)
{ {
/* /*
* Compute x = (7^5 * x) mod (2^31 - 1) * Compute x = (7^5 * x) mod (2^31 - 1)
* without overflowing 31 bits: * without overflowing 31 bits:
* (2^31 - 1) = 127773 * (7^5) + 2836 * (2^31 - 1) = 127773 * (7^5) + 2836
@ -31,7 +31,7 @@ do_rand(unsigned long *ctx)
hi = x / 127773; hi = x / 127773;
lo = x % 127773; lo = x % 127773;
x = 16807 * lo - 2836 * hi; x = 16807 * lo - 2836 * hi;
if (x < 0) if(x < 0)
x += 0x7fffffff; x += 0x7fffffff;
/* Transform to [0, 0x7ffffffd] range. */ /* Transform to [0, 0x7ffffffd] range. */
x--; x--;
@ -56,112 +56,112 @@ go(int which_child)
u64 iters = 0; u64 iters = 0;
mkdir("grindir"); mkdir("grindir");
if(chdir("grindir") != 0){ if(chdir("grindir") != 0) {
printf("grind: chdir grindir failed\n"); printf("grind: chdir grindir failed\n");
exit(1); exit(1);
} }
chdir("/"); chdir("/");
while(1){ while(1) {
iters++; iters++;
if((iters % 500) == 0) if((iters % 500) == 0)
write(1, which_child?"B":"A", 1); write(1, which_child ? "B" : "A", 1);
int what = rand() % 23; int what = rand() % 23;
if(what == 1){ if(what == 1) {
close(open("grindir/../a", O_CREATE|O_RDWR)); close(open("grindir/../a", O_CREATE | O_RDWR));
} else if(what == 2){ } else if(what == 2) {
close(open("grindir/../grindir/../b", O_CREATE|O_RDWR)); close(open("grindir/../grindir/../b", O_CREATE | O_RDWR));
} else if(what == 3){ } else if(what == 3) {
unlink("grindir/../a"); unlink("grindir/../a");
} else if(what == 4){ } else if(what == 4) {
if(chdir("grindir") != 0){ if(chdir("grindir") != 0) {
printf("grind: chdir grindir failed\n"); printf("grind: chdir grindir failed\n");
exit(1); exit(1);
} }
unlink("../b"); unlink("../b");
chdir("/"); chdir("/");
} else if(what == 5){ } else if(what == 5) {
close(fd); close(fd);
fd = open("/grindir/../a", O_CREATE|O_RDWR); fd = open("/grindir/../a", O_CREATE | O_RDWR);
} else if(what == 6){ } else if(what == 6) {
close(fd); close(fd);
fd = open("/./grindir/./../b", O_CREATE|O_RDWR); fd = open("/./grindir/./../b", O_CREATE | O_RDWR);
} else if(what == 7){ } else if(what == 7) {
write(fd, buf, sizeof(buf)); write(fd, buf, sizeof(buf));
} else if(what == 8){ } else if(what == 8) {
read(fd, buf, sizeof(buf)); read(fd, buf, sizeof(buf));
} else if(what == 9){ } else if(what == 9) {
mkdir("grindir/../a"); mkdir("grindir/../a");
close(open("a/../a/./a", O_CREATE|O_RDWR)); close(open("a/../a/./a", O_CREATE | O_RDWR));
unlink("a/a"); unlink("a/a");
} else if(what == 10){ } else if(what == 10) {
mkdir("/../b"); mkdir("/../b");
close(open("grindir/../b/b", O_CREATE|O_RDWR)); close(open("grindir/../b/b", O_CREATE | O_RDWR));
unlink("b/b"); unlink("b/b");
} else if(what == 11){ } else if(what == 11) {
unlink("b"); unlink("b");
link("../grindir/./../a", "../b"); link("../grindir/./../a", "../b");
} else if(what == 12){ } else if(what == 12) {
unlink("../grindir/../a"); unlink("../grindir/../a");
link(".././b", "/grindir/../a"); link(".././b", "/grindir/../a");
} else if(what == 13){ } else if(what == 13) {
int pid = fork(); int pid = fork();
if(pid == 0){ if(pid == 0) {
exit(0); exit(0);
} else if(pid < 0){ } else if(pid < 0) {
printf("grind: fork failed\n"); printf("grind: fork failed\n");
exit(1); exit(1);
} }
wait(0); wait(0);
} else if(what == 14){ } else if(what == 14) {
int pid = fork(); int pid = fork();
if(pid == 0){ if(pid == 0) {
fork(); fork();
fork(); fork();
exit(0); exit(0);
} else if(pid < 0){ } else if(pid < 0) {
printf("grind: fork failed\n"); printf("grind: fork failed\n");
exit(1); exit(1);
} }
wait(0); wait(0);
} else if(what == 15){ } else if(what == 15) {
sbrk(6011); sbrk(6011);
} else if(what == 16){ } else if(what == 16) {
if(sbrk(0) > break0) if(sbrk(0) > break0)
sbrk(-(sbrk(0) - break0)); sbrk(-(sbrk(0) - break0));
} else if(what == 17){ } else if(what == 17) {
int pid = fork(); int pid = fork();
if(pid == 0){ if(pid == 0) {
close(open("a", O_CREATE|O_RDWR)); close(open("a", O_CREATE | O_RDWR));
exit(0); exit(0);
} else if(pid < 0){ } else if(pid < 0) {
printf("grind: fork failed\n"); printf("grind: fork failed\n");
exit(1); exit(1);
} }
if(chdir("../grindir/..") != 0){ if(chdir("../grindir/..") != 0) {
printf("grind: chdir failed\n"); printf("grind: chdir failed\n");
exit(1); exit(1);
} }
kill(pid); kill(pid);
wait(0); wait(0);
} else if(what == 18){ } else if(what == 18) {
int pid = fork(); int pid = fork();
if(pid == 0){ if(pid == 0) {
kill(getpid()); kill(getpid());
exit(0); exit(0);
} else if(pid < 0){ } else if(pid < 0) {
printf("grind: fork failed\n"); printf("grind: fork failed\n");
exit(1); exit(1);
} }
wait(0); wait(0);
} else if(what == 19){ } else if(what == 19) {
int fds[2]; int fds[2];
if(pipe(fds) < 0){ if(pipe(fds) < 0) {
printf("grind: pipe failed\n"); printf("grind: pipe failed\n");
exit(1); exit(1);
} }
int pid = fork(); int pid = fork();
if(pid == 0){ if(pid == 0) {
fork(); fork();
fork(); fork();
if(write(fds[1], "x", 1) != 1) if(write(fds[1], "x", 1) != 1)
@ -170,74 +170,74 @@ go(int which_child)
if(read(fds[0], &c, 1) != 1) if(read(fds[0], &c, 1) != 1)
printf("grind: pipe read failed\n"); printf("grind: pipe read failed\n");
exit(0); exit(0);
} else if(pid < 0){ } else if(pid < 0) {
printf("grind: fork failed\n"); printf("grind: fork failed\n");
exit(1); exit(1);
} }
close(fds[0]); close(fds[0]);
close(fds[1]); close(fds[1]);
wait(0); wait(0);
} else if(what == 20){ } else if(what == 20) {
int pid = fork(); int pid = fork();
if(pid == 0){ if(pid == 0) {
unlink("a"); unlink("a");
mkdir("a"); mkdir("a");
chdir("a"); chdir("a");
unlink("../a"); unlink("../a");
fd = open("x", O_CREATE|O_RDWR); fd = open("x", O_CREATE | O_RDWR);
unlink("x"); unlink("x");
exit(0); exit(0);
} else if(pid < 0){ } else if(pid < 0) {
printf("grind: fork failed\n"); printf("grind: fork failed\n");
exit(1); exit(1);
} }
wait(0); wait(0);
} else if(what == 21){ } else if(what == 21) {
unlink("c"); unlink("c");
// should always succeed. check that there are free i-nodes, // should always succeed. check that there are free i-nodes,
// file descriptors, blocks. // file descriptors, blocks.
int fd1 = open("c", O_CREATE|O_RDWR); int fd1 = open("c", O_CREATE | O_RDWR);
if(fd1 < 0){ if(fd1 < 0) {
printf("grind: create c failed\n"); printf("grind: create c failed\n");
exit(1); exit(1);
} }
if(write(fd1, "x", 1) != 1){ if(write(fd1, "x", 1) != 1) {
printf("grind: write c failed\n"); printf("grind: write c failed\n");
exit(1); exit(1);
} }
struct stat st; struct stat st;
if(fstat(fd1, &st) != 0){ if(fstat(fd1, &st) != 0) {
printf("grind: fstat failed\n"); printf("grind: fstat failed\n");
exit(1); exit(1);
} }
if(st.size != 1){ if(st.size != 1) {
printf("grind: fstat reports wrong size %d\n", (int)st.size); printf("grind: fstat reports wrong size %d\n", (int)st.size);
exit(1); exit(1);
} }
if(st.ino > 200){ if(st.ino > 200) {
printf("grind: fstat reports crazy i-number %d\n", st.ino); printf("grind: fstat reports crazy i-number %d\n", st.ino);
exit(1); exit(1);
} }
close(fd1); close(fd1);
unlink("c"); unlink("c");
} else if(what == 22){ } else if(what == 22) {
// echo hi | cat // echo hi | cat
int aa[2], bb[2]; int aa[2], bb[2];
if(pipe(aa) < 0){ if(pipe(aa) < 0) {
fprintf(2, "grind: pipe failed\n"); fprintf(2, "grind: pipe failed\n");
exit(1); exit(1);
} }
if(pipe(bb) < 0){ if(pipe(bb) < 0) {
fprintf(2, "grind: pipe failed\n"); fprintf(2, "grind: pipe failed\n");
exit(1); exit(1);
} }
int pid1 = fork(); int pid1 = fork();
if(pid1 == 0){ if(pid1 == 0) {
close(bb[0]); close(bb[0]);
close(bb[1]); close(bb[1]);
close(aa[0]); close(aa[0]);
close(1); close(1);
if(dup(aa[1]) != 1){ if(dup(aa[1]) != 1) {
fprintf(2, "grind: dup failed\n"); fprintf(2, "grind: dup failed\n");
exit(1); exit(1);
} }
@ -246,22 +246,22 @@ go(int which_child)
exec("grindir/../echo", args); exec("grindir/../echo", args);
fprintf(2, "grind: echo: not found\n"); fprintf(2, "grind: echo: not found\n");
exit(2); exit(2);
} else if(pid1 < 0){ } else if(pid1 < 0) {
fprintf(2, "grind: fork failed\n"); fprintf(2, "grind: fork failed\n");
exit(3); exit(3);
} }
int pid2 = fork(); int pid2 = fork();
if(pid2 == 0){ if(pid2 == 0) {
close(aa[1]); close(aa[1]);
close(bb[0]); close(bb[0]);
close(0); close(0);
if(dup(aa[0]) != 0){ if(dup(aa[0]) != 0) {
fprintf(2, "grind: dup failed\n"); fprintf(2, "grind: dup failed\n");
exit(4); exit(4);
} }
close(aa[0]); close(aa[0]);
close(1); close(1);
if(dup(bb[1]) != 1){ if(dup(bb[1]) != 1) {
fprintf(2, "grind: dup failed\n"); fprintf(2, "grind: dup failed\n");
exit(5); exit(5);
} }
@ -270,7 +270,7 @@ go(int which_child)
exec("/cat", args); exec("/cat", args);
fprintf(2, "grind: cat: not found\n"); fprintf(2, "grind: cat: not found\n");
exit(6); exit(6);
} else if(pid2 < 0){ } else if(pid2 < 0) {
fprintf(2, "grind: fork failed\n"); fprintf(2, "grind: fork failed\n");
exit(7); exit(7);
} }
@ -278,14 +278,14 @@ go(int which_child)
close(aa[1]); close(aa[1]);
close(bb[1]); close(bb[1]);
char buf[4] = { 0, 0, 0, 0 }; char buf[4] = { 0, 0, 0, 0 };
read(bb[0], buf+0, 1); read(bb[0], buf + 0, 1);
read(bb[0], buf+1, 1); read(bb[0], buf + 1, 1);
read(bb[0], buf+2, 1); read(bb[0], buf + 2, 1);
close(bb[0]); close(bb[0]);
int st1, st2; int st1, st2;
wait(&st1); wait(&st1);
wait(&st2); wait(&st2);
if(st1 != 0 || st2 != 0 || strcmp(buf, "hi\n") != 0){ if(st1 != 0 || st2 != 0 || strcmp(buf, "hi\n") != 0) {
printf("grind: exec pipeline failed %d %d \"%s\"\n", st1, st2, buf); printf("grind: exec pipeline failed %d %d \"%s\"\n", st1, st2, buf);
exit(1); exit(1);
} }
@ -300,22 +300,22 @@ iter()
unlink("b"); unlink("b");
int pid1 = fork(); int pid1 = fork();
if(pid1 < 0){ if(pid1 < 0) {
printf("grind: fork failed\n"); printf("grind: fork failed\n");
exit(1); exit(1);
} }
if(pid1 == 0){ if(pid1 == 0) {
rand_next ^= 31; rand_next ^= 31;
go(0); go(0);
exit(0); exit(0);
} }
int pid2 = fork(); int pid2 = fork();
if(pid2 < 0){ if(pid2 < 0) {
printf("grind: fork failed\n"); printf("grind: fork failed\n");
exit(1); exit(1);
} }
if(pid2 == 0){ if(pid2 == 0) {
rand_next ^= 7177; rand_next ^= 7177;
go(1); go(1);
exit(0); exit(0);
@ -323,7 +323,7 @@ iter()
int st1 = -1; int st1 = -1;
wait(&st1); wait(&st1);
if(st1 != 0){ if(st1 != 0) {
kill(pid1); kill(pid1);
kill(pid2); kill(pid2);
} }
@ -336,13 +336,13 @@ iter()
int int
main() main()
{ {
while(1){ while(1) {
int pid = fork(); int pid = fork();
if(pid == 0){ if(pid == 0) {
iter(); iter();
exit(0); exit(0);
} }
if(pid > 0){ if(pid > 0) {
wait(0); wait(0);
} }
sleep(20); sleep(20);

16
user/init.c
View file

@ -16,34 +16,34 @@ main(void)
{ {
int pid, wpid; int pid, wpid;
if(open("console", O_RDWR) < 0){ if(open("console", O_RDWR) < 0) {
mknod("console", CONSOLE, 0); mknod("console", CONSOLE, 0);
open("console", O_RDWR); open("console", O_RDWR);
} }
dup(0); // stdout dup(0); // stdout
dup(0); // stderr dup(0); // stderr
for(;;){ for(;;) {
printf("init: starting sh\n"); printf("init: starting sh\n");
pid = fork(); pid = fork();
if(pid < 0){ if(pid < 0) {
printf("init: fork failed\n"); printf("init: fork failed\n");
exit(1); exit(1);
} }
if(pid == 0){ if(pid == 0) {
exec("sh", argv); exec("sh", argv);
printf("init: exec sh failed\n"); printf("init: exec sh failed\n");
exit(1); exit(1);
} }
for(;;){ for(;;) {
// this call to wait() returns if the shell exits, // this call to wait() returns if the shell exits,
// or if a parentless process exits. // or if a parentless process exits.
wpid = wait((int *) 0); wpid = wait((int *)0);
if(wpid == pid){ if(wpid == pid) {
// the shell exited; restart it. // the shell exited; restart it.
break; break;
} else if(wpid < 0){ } else if(wpid < 0) {
printf("init: wait returned an error\n"); printf("init: wait returned an error\n");
exit(1); exit(1);
} else { } else {

4
user/kill.c
View file

@ -7,11 +7,11 @@ main(int argc, char **argv)
{ {
int i; int i;
if(argc < 2){ if(argc < 2) {
fprintf(2, "usage: kill pid...\n"); fprintf(2, "usage: kill pid...\n");
exit(1); exit(1);
} }
for(i=1; i<argc; i++) for(i = 1; i < argc; i++)
kill(atoi(argv[i])); kill(atoi(argv[i]));
exit(0); exit(0);
} }

2
user/ln.c
View file

@ -5,7 +5,7 @@
int int
main(int argc, char *argv[]) main(int argc, char *argv[])
{ {
if(argc != 3){ if(argc != 3) {
fprintf(2, "Usage: ln old new\n"); fprintf(2, "Usage: ln old new\n");
exit(1); exit(1);
} }

26
user/ls.c
View file

@ -3,14 +3,14 @@
#include "user/user.h" #include "user/user.h"
#include "kernel/fs.h" #include "kernel/fs.h"
char* char *
fmtname(char *path) fmtname(char *path)
{ {
static char buf[DIRSIZ+1]; static char buf[DIRSIZ + 1];
char *p; char *p;
// Find first character after last slash. // Find first character after last slash.
for(p=path+strlen(path); p >= path && *p != '/'; p--) for(p = path + strlen(path); p >= path && *p != '/'; p--)
; ;
p++; p++;
@ -18,7 +18,7 @@ fmtname(char *path)
if(strlen(p) >= DIRSIZ) if(strlen(p) >= DIRSIZ)
return p; return p;
memmove(buf, p, strlen(p)); memmove(buf, p, strlen(p));
memset(buf+strlen(p), ' ', DIRSIZ-strlen(p)); memset(buf + strlen(p), ' ', DIRSIZ - strlen(p));
return buf; return buf;
} }
@ -30,37 +30,37 @@ ls(char *path)
struct dirent de; struct dirent de;
struct stat st; struct stat st;
if((fd = open(path, 0)) < 0){ if((fd = open(path, 0)) < 0) {
fprintf(2, "ls: cannot open %s\n", path); fprintf(2, "ls: cannot open %s\n", path);
return; return;
} }
if(fstat(fd, &st) < 0){ if(fstat(fd, &st) < 0) {
fprintf(2, "ls: cannot stat %s\n", path); fprintf(2, "ls: cannot stat %s\n", path);
close(fd); close(fd);
return; return;
} }
switch(st.type){ switch(st.type) {
case T_DEVICE: case T_DEVICE:
case T_FILE: case T_FILE:
printf("%s %d %d %l\n", fmtname(path), st.type, st.ino, st.size); printf("%s %d %d %l\n", fmtname(path), st.type, st.ino, st.size);
break; break;
case T_DIR: case T_DIR:
if(strlen(path) + 1 + DIRSIZ + 1 > sizeof buf){ if(strlen(path) + 1 + DIRSIZ + 1 > sizeof buf) {
printf("ls: path too long\n"); printf("ls: path too long\n");
break; break;
} }
strcpy(buf, path); strcpy(buf, path);
p = buf+strlen(buf); p = buf + strlen(buf);
*p++ = '/'; *p++ = '/';
while(read(fd, &de, sizeof(de)) == sizeof(de)){ while(read(fd, &de, sizeof(de)) == sizeof(de)) {
if(de.inum == 0) if(de.inum == 0)
continue; continue;
memmove(p, de.name, DIRSIZ); memmove(p, de.name, DIRSIZ);
p[DIRSIZ] = 0; p[DIRSIZ] = 0;
if(stat(buf, &st) < 0){ if(stat(buf, &st) < 0) {
printf("ls: cannot stat %s\n", buf); printf("ls: cannot stat %s\n", buf);
continue; continue;
} }
@ -76,11 +76,11 @@ main(int argc, char *argv[])
{ {
int i; int i;
if(argc < 2){ if(argc < 2) {
ls("."); ls(".");
exit(0); exit(0);
} }
for(i=1; i<argc; i++) for(i = 1; i < argc; i++)
ls(argv[i]); ls(argv[i]);
exit(0); exit(0);
} }

6
user/mkdir.c
View file

@ -7,13 +7,13 @@ main(int argc, char *argv[])
{ {
int i; int i;
if(argc < 2){ if(argc < 2) {
fprintf(2, "Usage: mkdir files...\n"); fprintf(2, "Usage: mkdir files...\n");
exit(1); exit(1);
} }
for(i = 1; i < argc; i++){ for(i = 1; i < argc; i++) {
if(mkdir(argv[i]) < 0){ if(mkdir(argv[i]) < 0) {
fprintf(2, "mkdir: %s failed to create\n", argv[i]); fprintf(2, "mkdir: %s failed to create\n", argv[i]);
break; break;
} }

31
user/printf.c
View file

@ -20,7 +20,7 @@ printint(int fd, int xx, int base, int sgn)
u32 x; u32 x;
neg = 0; neg = 0;
if(sgn && xx < 0){ if(sgn && xx < 0) {
neg = 1; neg = 1;
x = -xx; x = -xx;
} else { } else {
@ -28,9 +28,9 @@ printint(int fd, int xx, int base, int sgn)
} }
i = 0; i = 0;
do{ do {
buf[i++] = digits[x % base]; buf[i++] = digits[x % base];
}while((x /= base) != 0); } while((x /= base) != 0);
if(neg) if(neg)
buf[i++] = '-'; buf[i++] = '-';
@ -39,11 +39,12 @@ printint(int fd, int xx, int base, int sgn)
} }
static void static void
printptr(int fd, u64 x) { printptr(int fd, u64 x)
{
int i; int i;
putc(fd, '0'); putc(fd, '0');
putc(fd, 'x'); putc(fd, 'x');
for (i = 0; i < (sizeof(u64) * 2); i++, x <<= 4) for(i = 0; i < (sizeof(u64) * 2); i++, x <<= 4)
putc(fd, digits[x >> (sizeof(u64) * 8 - 4)]); putc(fd, digits[x >> (sizeof(u64) * 8 - 4)]);
} }
@ -55,16 +56,16 @@ vprintf(int fd, const char *fmt, va_list ap)
int c, i, state; int c, i, state;
state = 0; state = 0;
for(i = 0; fmt[i]; i++){ for(i = 0; fmt[i]; i++) {
c = fmt[i] & 0xff; c = fmt[i] & 0xff;
if(state == 0){ if(state == 0) {
if(c == '%'){ if(c == '%') {
state = '%'; state = '%';
} else { } else {
putc(fd, c); putc(fd, c);
} }
} else if(state == '%'){ } else if(state == '%') {
if(c == 'd'){ if(c == 'd') {
printint(fd, va_arg(ap, int), 10, 1); printint(fd, va_arg(ap, int), 10, 1);
} else if(c == 'l') { } else if(c == 'l') {
printint(fd, va_arg(ap, u64), 10, 0); printint(fd, va_arg(ap, u64), 10, 0);
@ -72,17 +73,17 @@ vprintf(int fd, const char *fmt, va_list ap)
printint(fd, va_arg(ap, int), 16, 0); printint(fd, va_arg(ap, int), 16, 0);
} else if(c == 'p') { } else if(c == 'p') {
printptr(fd, va_arg(ap, u64)); printptr(fd, va_arg(ap, u64));
} else if(c == 's'){ } else if(c == 's') {
s = va_arg(ap, char*); s = va_arg(ap, char *);
if(s == 0) if(s == 0)
s = "(null)"; s = "(null)";
while(*s != 0){ while(*s != 0) {
putc(fd, *s); putc(fd, *s);
s++; s++;
} }
} else if(c == 'c'){ } else if(c == 'c') {
putc(fd, va_arg(ap, u32)); putc(fd, va_arg(ap, u32));
} else if(c == '%'){ } else if(c == '%') {
putc(fd, c); putc(fd, c);
} else { } else {
// Unknown % sequence. Print it to draw attention. // Unknown % sequence. Print it to draw attention.

6
user/rm.c
View file

@ -7,13 +7,13 @@ main(int argc, char *argv[])
{ {
int i; int i;
if(argc < 2){ if(argc < 2) {
fprintf(2, "Usage: rm files...\n"); fprintf(2, "Usage: rm files...\n");
exit(1); exit(1);
} }
for(i = 1; i < argc; i++){ for(i = 1; i < argc; i++) {
if(unlink(argv[i]) < 0){ if(unlink(argv[i]) < 0) {
fprintf(2, "rm: %s failed to delete\n", argv[i]); fprintf(2, "rm: %s failed to delete\n", argv[i]);
break; break;
} }

124
user/sh.c
View file

@ -50,9 +50,9 @@ struct backcmd {
}; };
int fork1(void); // Fork but panics on failure. int fork1(void); // Fork but panics on failure.
void panic(char*); void panic(char *);
struct cmd *parsecmd(char*); struct cmd *parsecmd(char *);
void runcmd(struct cmd*) __attribute__((noreturn)); void runcmd(struct cmd *) __attribute__((noreturn));
// Execute cmd. Never returns. // Execute cmd. Never returns.
void void
@ -68,12 +68,12 @@ runcmd(struct cmd *cmd)
if(cmd == 0) if(cmd == 0)
exit(1); exit(1);
switch(cmd->type){ switch(cmd->type) {
default: default:
panic("runcmd"); panic("runcmd");
case EXEC: case EXEC:
ecmd = (struct execcmd*)cmd; ecmd = (struct execcmd *)cmd;
if(ecmd->argv[0] == 0) if(ecmd->argv[0] == 0)
exit(1); exit(1);
exec(ecmd->argv[0], ecmd->argv); exec(ecmd->argv[0], ecmd->argv);
@ -81,9 +81,9 @@ runcmd(struct cmd *cmd)
break; break;
case REDIR: case REDIR:
rcmd = (struct redircmd*)cmd; rcmd = (struct redircmd *)cmd;
close(rcmd->fd); close(rcmd->fd);
if(open(rcmd->file, rcmd->mode) < 0){ if(open(rcmd->file, rcmd->mode) < 0) {
fprintf(2, "open %s failed\n", rcmd->file); fprintf(2, "open %s failed\n", rcmd->file);
exit(1); exit(1);
} }
@ -91,7 +91,7 @@ runcmd(struct cmd *cmd)
break; break;
case LIST: case LIST:
lcmd = (struct listcmd*)cmd; lcmd = (struct listcmd *)cmd;
if(fork1() == 0) if(fork1() == 0)
runcmd(lcmd->left); runcmd(lcmd->left);
wait(0); wait(0);
@ -99,17 +99,17 @@ runcmd(struct cmd *cmd)
break; break;
case PIPE: case PIPE:
pcmd = (struct pipecmd*)cmd; pcmd = (struct pipecmd *)cmd;
if(pipe(p) < 0) if(pipe(p) < 0)
panic("pipe"); panic("pipe");
if(fork1() == 0){ if(fork1() == 0) {
close(1); close(1);
dup(p[1]); dup(p[1]);
close(p[0]); close(p[0]);
close(p[1]); close(p[1]);
runcmd(pcmd->left); runcmd(pcmd->left);
} }
if(fork1() == 0){ if(fork1() == 0) {
close(0); close(0);
dup(p[0]); dup(p[0]);
close(p[0]); close(p[0]);
@ -123,7 +123,7 @@ runcmd(struct cmd *cmd)
break; break;
case BACK: case BACK:
bcmd = (struct backcmd*)cmd; bcmd = (struct backcmd *)cmd;
if(fork1() == 0) if(fork1() == 0)
runcmd(bcmd->cmd); runcmd(bcmd->cmd);
break; break;
@ -149,20 +149,20 @@ main(void)
int fd; int fd;
// Ensure that three file descriptors are open. // Ensure that three file descriptors are open.
while((fd = open("console", O_RDWR)) >= 0){ while((fd = open("console", O_RDWR)) >= 0) {
if(fd >= 3){ if(fd >= 3) {
close(fd); close(fd);
break; break;
} }
} }
// Read and run input commands. // Read and run input commands.
while(getcmd(buf, sizeof(buf)) >= 0){ while(getcmd(buf, sizeof(buf)) >= 0) {
if(buf[0] == 'c' && buf[1] == 'd' && buf[2] == ' '){ if(buf[0] == 'c' && buf[1] == 'd' && buf[2] == ' ') {
// Chdir must be called by the parent, not the child. // Chdir must be called by the parent, not the child.
buf[strlen(buf)-1] = 0; // chop \n buf[strlen(buf) - 1] = 0; // chop \n
if(chdir(buf+3) < 0) if(chdir(buf + 3) < 0)
fprintf(2, "cannot cd %s\n", buf+3); fprintf(2, "cannot cd %s\n", buf + 3);
continue; continue;
} }
if(fork1() == 0) if(fork1() == 0)
@ -190,10 +190,10 @@ fork1(void)
return pid; return pid;
} }
//PAGEBREAK! // PAGEBREAK!
// Constructors // Constructors
struct cmd* struct cmd *
execcmd(void) execcmd(void)
{ {
struct execcmd *cmd; struct execcmd *cmd;
@ -201,10 +201,10 @@ execcmd(void)
cmd = malloc(sizeof(*cmd)); cmd = malloc(sizeof(*cmd));
memset(cmd, 0, sizeof(*cmd)); memset(cmd, 0, sizeof(*cmd));
cmd->type = EXEC; cmd->type = EXEC;
return (struct cmd*)cmd; return (struct cmd *)cmd;
} }
struct cmd* struct cmd *
redircmd(struct cmd *subcmd, char *file, char *efile, int mode, int fd) redircmd(struct cmd *subcmd, char *file, char *efile, int mode, int fd)
{ {
struct redircmd *cmd; struct redircmd *cmd;
@ -217,10 +217,10 @@ redircmd(struct cmd *subcmd, char *file, char *efile, int mode, int fd)
cmd->efile = efile; cmd->efile = efile;
cmd->mode = mode; cmd->mode = mode;
cmd->fd = fd; cmd->fd = fd;
return (struct cmd*)cmd; return (struct cmd *)cmd;
} }
struct cmd* struct cmd *
pipecmd(struct cmd *left, struct cmd *right) pipecmd(struct cmd *left, struct cmd *right)
{ {
struct pipecmd *cmd; struct pipecmd *cmd;
@ -230,10 +230,10 @@ pipecmd(struct cmd *left, struct cmd *right)
cmd->type = PIPE; cmd->type = PIPE;
cmd->left = left; cmd->left = left;
cmd->right = right; cmd->right = right;
return (struct cmd*)cmd; return (struct cmd *)cmd;
} }
struct cmd* struct cmd *
listcmd(struct cmd *left, struct cmd *right) listcmd(struct cmd *left, struct cmd *right)
{ {
struct listcmd *cmd; struct listcmd *cmd;
@ -243,10 +243,10 @@ listcmd(struct cmd *left, struct cmd *right)
cmd->type = LIST; cmd->type = LIST;
cmd->left = left; cmd->left = left;
cmd->right = right; cmd->right = right;
return (struct cmd*)cmd; return (struct cmd *)cmd;
} }
struct cmd* struct cmd *
backcmd(struct cmd *subcmd) backcmd(struct cmd *subcmd)
{ {
struct backcmd *cmd; struct backcmd *cmd;
@ -255,9 +255,9 @@ backcmd(struct cmd *subcmd)
memset(cmd, 0, sizeof(*cmd)); memset(cmd, 0, sizeof(*cmd));
cmd->type = BACK; cmd->type = BACK;
cmd->cmd = subcmd; cmd->cmd = subcmd;
return (struct cmd*)cmd; return (struct cmd *)cmd;
} }
//PAGEBREAK! // PAGEBREAK!
// Parsing // Parsing
char whitespace[] = " \t\r\n\v"; char whitespace[] = " \t\r\n\v";
@ -275,7 +275,7 @@ gettoken(char **ps, char *es, char **q, char **eq)
if(q) if(q)
*q = s; *q = s;
ret = *s; ret = *s;
switch(*s){ switch(*s) {
case 0: case 0:
break; break;
case '|': case '|':
@ -288,7 +288,7 @@ gettoken(char **ps, char *es, char **q, char **eq)
break; break;
case '>': case '>':
s++; s++;
if(*s == '>'){ if(*s == '>') {
ret = '+'; ret = '+';
s++; s++;
} }
@ -320,12 +320,12 @@ peek(char **ps, char *es, char *toks)
return *s && strchr(toks, *s); return *s && strchr(toks, *s);
} }
struct cmd *parseline(char**, char*); struct cmd *parseline(char **, char *);
struct cmd *parsepipe(char**, char*); struct cmd *parsepipe(char **, char *);
struct cmd *parseexec(char**, char*); struct cmd *parseexec(char **, char *);
struct cmd *nulterminate(struct cmd*); struct cmd *nulterminate(struct cmd *);
struct cmd* struct cmd *
parsecmd(char *s) parsecmd(char *s)
{ {
char *es; char *es;
@ -334,7 +334,7 @@ parsecmd(char *s)
es = s + strlen(s); es = s + strlen(s);
cmd = parseline(&s, es); cmd = parseline(&s, es);
peek(&s, es, ""); peek(&s, es, "");
if(s != es){ if(s != es) {
fprintf(2, "leftovers: %s\n", s); fprintf(2, "leftovers: %s\n", s);
panic("syntax"); panic("syntax");
} }
@ -342,62 +342,62 @@ parsecmd(char *s)
return cmd; return cmd;
} }
struct cmd* struct cmd *
parseline(char **ps, char *es) parseline(char **ps, char *es)
{ {
struct cmd *cmd; struct cmd *cmd;
cmd = parsepipe(ps, es); cmd = parsepipe(ps, es);
while(peek(ps, es, "&")){ while(peek(ps, es, "&")) {
gettoken(ps, es, 0, 0); gettoken(ps, es, 0, 0);
cmd = backcmd(cmd); cmd = backcmd(cmd);
} }
if(peek(ps, es, ";")){ if(peek(ps, es, ";")) {
gettoken(ps, es, 0, 0); gettoken(ps, es, 0, 0);
cmd = listcmd(cmd, parseline(ps, es)); cmd = listcmd(cmd, parseline(ps, es));
} }
return cmd; return cmd;
} }
struct cmd* struct cmd *
parsepipe(char **ps, char *es) parsepipe(char **ps, char *es)
{ {
struct cmd *cmd; struct cmd *cmd;
cmd = parseexec(ps, es); cmd = parseexec(ps, es);
if(peek(ps, es, "|")){ if(peek(ps, es, "|")) {
gettoken(ps, es, 0, 0); gettoken(ps, es, 0, 0);
cmd = pipecmd(cmd, parsepipe(ps, es)); cmd = pipecmd(cmd, parsepipe(ps, es));
} }
return cmd; return cmd;
} }
struct cmd* struct cmd *
parseredirs(struct cmd *cmd, char **ps, char *es) parseredirs(struct cmd *cmd, char **ps, char *es)
{ {
int tok; int tok;
char *q, *eq; char *q, *eq;
while(peek(ps, es, "<>")){ while(peek(ps, es, "<>")) {
tok = gettoken(ps, es, 0, 0); tok = gettoken(ps, es, 0, 0);
if(gettoken(ps, es, &q, &eq) != 'a') if(gettoken(ps, es, &q, &eq) != 'a')
panic("missing file for redirection"); panic("missing file for redirection");
switch(tok){ switch(tok) {
case '<': case '<':
cmd = redircmd(cmd, q, eq, O_RDONLY, 0); cmd = redircmd(cmd, q, eq, O_RDONLY, 0);
break; break;
case '>': case '>':
cmd = redircmd(cmd, q, eq, O_WRONLY|O_CREATE|O_TRUNC, 1); cmd = redircmd(cmd, q, eq, O_WRONLY | O_CREATE | O_TRUNC, 1);
break; break;
case '+': // >> case '+': // >>
cmd = redircmd(cmd, q, eq, O_WRONLY|O_CREATE, 1); cmd = redircmd(cmd, q, eq, O_WRONLY | O_CREATE, 1);
break; break;
} }
} }
return cmd; return cmd;
} }
struct cmd* struct cmd *
parseblock(char **ps, char *es) parseblock(char **ps, char *es)
{ {
struct cmd *cmd; struct cmd *cmd;
@ -413,7 +413,7 @@ parseblock(char **ps, char *es)
return cmd; return cmd;
} }
struct cmd* struct cmd *
parseexec(char **ps, char *es) parseexec(char **ps, char *es)
{ {
char *q, *eq; char *q, *eq;
@ -425,12 +425,12 @@ parseexec(char **ps, char *es)
return parseblock(ps, es); return parseblock(ps, es);
ret = execcmd(); ret = execcmd();
cmd = (struct execcmd*)ret; cmd = (struct execcmd *)ret;
argc = 0; argc = 0;
ret = parseredirs(ret, ps, es); ret = parseredirs(ret, ps, es);
while(!peek(ps, es, "|)&;")){ while(!peek(ps, es, "|)&;")) {
if((tok=gettoken(ps, es, &q, &eq)) == 0) if((tok = gettoken(ps, es, &q, &eq)) == 0)
break; break;
if(tok != 'a') if(tok != 'a')
panic("syntax"); panic("syntax");
@ -447,7 +447,7 @@ parseexec(char **ps, char *es)
} }
// NUL-terminate all the counted strings. // NUL-terminate all the counted strings.
struct cmd* struct cmd *
nulterminate(struct cmd *cmd) nulterminate(struct cmd *cmd)
{ {
int i; int i;
@ -460,33 +460,33 @@ nulterminate(struct cmd *cmd)
if(cmd == 0) if(cmd == 0)
return 0; return 0;
switch(cmd->type){ switch(cmd->type) {
case EXEC: case EXEC:
ecmd = (struct execcmd*)cmd; ecmd = (struct execcmd *)cmd;
for(i=0; ecmd->argv[i]; i++) for(i = 0; ecmd->argv[i]; i++)
*ecmd->eargv[i] = 0; *ecmd->eargv[i] = 0;
break; break;
case REDIR: case REDIR:
rcmd = (struct redircmd*)cmd; rcmd = (struct redircmd *)cmd;
nulterminate(rcmd->cmd); nulterminate(rcmd->cmd);
*rcmd->efile = 0; *rcmd->efile = 0;
break; break;
case PIPE: case PIPE:
pcmd = (struct pipecmd*)cmd; pcmd = (struct pipecmd *)cmd;
nulterminate(pcmd->left); nulterminate(pcmd->left);
nulterminate(pcmd->right); nulterminate(pcmd->right);
break; break;
case LIST: case LIST:
lcmd = (struct listcmd*)cmd; lcmd = (struct listcmd *)cmd;
nulterminate(lcmd->left); nulterminate(lcmd->left);
nulterminate(lcmd->right); nulterminate(lcmd->right);
break; break;
case BACK: case BACK:
bcmd = (struct backcmd*)cmd; bcmd = (struct backcmd *)cmd;
nulterminate(bcmd->cmd); nulterminate(bcmd->cmd);
break; break;
} }

4
user/stressfs.c
View file

@ -32,14 +32,14 @@ main(int argc, char *argv[])
path[8] += i; path[8] += i;
fd = open(path, O_CREATE | O_RDWR); fd = open(path, O_CREATE | O_RDWR);
for(i = 0; i < 20; i++) for(i = 0; i < 20; i++)
// printf(fd, "%d\n", i); // printf(fd, "%d\n", i);
write(fd, data, sizeof(data)); write(fd, data, sizeof(data));
close(fd); close(fd);
printf("read\n"); printf("read\n");
fd = open(path, O_RDONLY); fd = open(path, O_RDONLY);
for (i = 0; i < 20; i++) for(i = 0; i < 20; i++)
read(fd, data, sizeof(data)); read(fd, data, sizeof(data));
close(fd); close(fd);

26
user/ulib.c
View file

@ -14,7 +14,7 @@ _main()
exit(0); exit(0);
} }
char* char *
strcpy(char *s, const char *t) strcpy(char *s, const char *t)
{ {
char *os; char *os;
@ -43,33 +43,33 @@ strlen(const char *s)
return n; return n;
} }
void* void *
memset(void *dst, int c, u32 n) memset(void *dst, int c, u32 n)
{ {
char *cdst = (char *) dst; char *cdst = (char *)dst;
int i; int i;
for(i = 0; i < n; i++){ for(i = 0; i < n; i++) {
cdst[i] = c; cdst[i] = c;
} }
return dst; return dst;
} }
char* char *
strchr(const char *s, char c) strchr(const char *s, char c)
{ {
for(; *s; s++) for(; *s; s++)
if(*s == c) if(*s == c)
return (char*)s; return (char *)s;
return 0; return 0;
} }
char* char *
gets(char *buf, int max) gets(char *buf, int max)
{ {
int i, cc; int i, cc;
char c; char c;
for(i=0; i+1 < max; ){ for(i = 0; i + 1 < max;) {
cc = read(0, &c, 1); cc = read(0, &c, 1);
if(cc < 1) if(cc < 1)
break; break;
@ -102,11 +102,11 @@ atoi(const char *s)
n = 0; n = 0;
while('0' <= *s && *s <= '9') while('0' <= *s && *s <= '9')
n = n*10 + *s++ - '0'; n = n * 10 + *s++ - '0';
return n; return n;
} }
void* void *
memmove(void *vdst, const void *vsrc, int n) memmove(void *vdst, const void *vsrc, int n)
{ {
char *dst; char *dst;
@ -114,7 +114,7 @@ memmove(void *vdst, const void *vsrc, int n)
dst = vdst; dst = vdst;
src = vsrc; src = vsrc;
if (src > dst) { if(src > dst) {
while(n-- > 0) while(n-- > 0)
*dst++ = *src++; *dst++ = *src++;
} else { } else {
@ -130,8 +130,8 @@ int
memcmp(const void *s1, const void *s2, u32 n) memcmp(const void *s1, const void *s2, u32 n)
{ {
const char *p1 = s1, *p2 = s2; const char *p1 = s1, *p2 = s2;
while (n-- > 0) { while(n-- > 0) {
if (*p1 != *p2) { if(*p1 != *p2) {
return *p1 - *p2; return *p1 - *p2;
} }
p1++; p1++;

26
user/umalloc.c
View file

@ -26,16 +26,16 @@ free(void *ap)
{ {
Header *bp, *p; Header *bp, *p;
bp = (Header*)ap - 1; bp = (Header *)ap - 1;
for(p = freep; !(bp > p && bp < p->s.ptr); p = p->s.ptr) for(p = freep; !(bp > p && bp < p->s.ptr); p = p->s.ptr)
if(p >= p->s.ptr && (bp > p || bp < p->s.ptr)) if(p >= p->s.ptr && (bp > p || bp < p->s.ptr))
break; break;
if(bp + bp->s.size == p->s.ptr){ if(bp + bp->s.size == p->s.ptr) {
bp->s.size += p->s.ptr->s.size; bp->s.size += p->s.ptr->s.size;
bp->s.ptr = p->s.ptr->s.ptr; bp->s.ptr = p->s.ptr->s.ptr;
} else } else
bp->s.ptr = p->s.ptr; bp->s.ptr = p->s.ptr;
if(p + p->s.size == bp){ if(p + p->s.size == bp) {
p->s.size += bp->s.size; p->s.size += bp->s.size;
p->s.ptr = bp->s.ptr; p->s.ptr = bp->s.ptr;
} else } else
@ -43,7 +43,7 @@ free(void *ap)
freep = p; freep = p;
} }
static Header* static Header *
morecore(u32 nu) morecore(u32 nu)
{ {
char *p; char *p;
@ -52,27 +52,27 @@ morecore(u32 nu)
if(nu < 4096) if(nu < 4096)
nu = 4096; nu = 4096;
p = sbrk(nu * sizeof(Header)); p = sbrk(nu * sizeof(Header));
if(p == (char*)-1) if(p == (char *)-1)
return 0; return 0;
hp = (Header*)p; hp = (Header *)p;
hp->s.size = nu; hp->s.size = nu;
free((void*)(hp + 1)); free((void *)(hp + 1));
return freep; return freep;
} }
void* void *
malloc(u32 nbytes) malloc(u32 nbytes)
{ {
Header *p, *prevp; Header *p, *prevp;
u32 nunits; u32 nunits;
nunits = (nbytes + sizeof(Header) - 1)/sizeof(Header) + 1; nunits = (nbytes + sizeof(Header) - 1) / sizeof(Header) + 1;
if((prevp = freep) == 0){ if((prevp = freep) == 0) {
base.s.ptr = freep = prevp = &base; base.s.ptr = freep = prevp = &base;
base.s.size = 0; base.s.size = 0;
} }
for(p = prevp->s.ptr; ; prevp = p, p = p->s.ptr){ for(p = prevp->s.ptr;; prevp = p, p = p->s.ptr) {
if(p->s.size >= nunits){ if(p->s.size >= nunits) {
if(p->s.size == nunits) if(p->s.size == nunits)
prevp->s.ptr = p->s.ptr; prevp->s.ptr = p->s.ptr;
else { else {
@ -81,7 +81,7 @@ malloc(u32 nbytes)
p->s.size = nunits; p->s.size = nunits;
} }
freep = prevp; freep = prevp;
return (void*)(p + 1); return (void *)(p + 1);
} }
if(p == freep) if(p == freep)
if((p = morecore(nunits)) == 0) if((p = morecore(nunits)) == 0)

52
user/user.h
View file

@ -3,39 +3,39 @@ struct stat;
// system calls // system calls
int fork(void); int fork(void);
int exit(int) __attribute__((noreturn)); int exit(int) __attribute__((noreturn));
int wait(int*); int wait(int *);
int pipe(int*); int pipe(int *);
int write(int, const void*, int); int write(int, const void *, int);
int read(int, void*, int); int read(int, void *, int);
int close(int); int close(int);
int kill(int); int kill(int);
int exec(const char*, char**); int exec(const char *, char **);
int open(const char*, int); int open(const char *, int);
int mknod(const char*, short, short); int mknod(const char *, short, short);
int unlink(const char*); int unlink(const char *);
int fstat(int fd, struct stat*); int fstat(int fd, struct stat *);
int link(const char*, const char*); int link(const char *, const char *);
int mkdir(const char*); int mkdir(const char *);
int chdir(const char*); int chdir(const char *);
int dup(int); int dup(int);
int getpid(void); int getpid(void);
char* sbrk(int); char *sbrk(int);
int sleep(int); int sleep(int);
int uptime(void); int uptime(void);
// ulib.c // ulib.c
int stat(const char*, struct stat*); int stat(const char *, struct stat *);
char* strcpy(char*, const char*); char *strcpy(char *, const char *);
void *memmove(void*, const void*, int); void *memmove(void *, const void *, int);
char* strchr(const char*, char c); char *strchr(const char *, char c);
int strcmp(const char*, const char*); int strcmp(const char *, const char *);
void fprintf(int, const char*, ...); void fprintf(int, const char *, ...);
void printf(const char*, ...); void printf(const char *, ...);
char* gets(char*, int max); char *gets(char *, int max);
u32 strlen(const char*); u32 strlen(const char *);
void* memset(void*, int, u32); void *memset(void *, int, u32);
void* malloc(u32); void *malloc(u32);
void free(void*); void free(void *);
int atoi(const char*); int atoi(const char *);
int memcmp(const void *, const void *, u32); int memcmp(const void *, const void *, u32);
void *memcpy(void *, const void *, u32); void *memcpy(void *, const void *, u32);

1118
user/usertests.c
View file

File diff suppressed because it is too large Load diff

14
user/wc.c
View file

@ -12,20 +12,20 @@ wc(int fd, char *name)
l = w = c = 0; l = w = c = 0;
inword = 0; inword = 0;
while((n = read(fd, buf, sizeof(buf))) > 0){ while((n = read(fd, buf, sizeof(buf))) > 0) {
for(i=0; i<n; i++){ for(i = 0; i < n; i++) {
c++; c++;
if(buf[i] == '\n') if(buf[i] == '\n')
l++; l++;
if(strchr(" \r\t\n\v", buf[i])) if(strchr(" \r\t\n\v", buf[i]))
inword = 0; inword = 0;
else if(!inword){ else if(!inword) {
w++; w++;
inword = 1; inword = 1;
} }
} }
} }
if(n < 0){ if(n < 0) {
printf("wc: read error\n"); printf("wc: read error\n");
exit(1); exit(1);
} }
@ -37,13 +37,13 @@ main(int argc, char *argv[])
{ {
int fd, i; int fd, i;
if(argc <= 1){ if(argc <= 1) {
wc(0, ""); wc(0, "");
exit(0); exit(0);
} }
for(i = 1; i < argc; i++){ for(i = 1; i < argc; i++) {
if((fd = open(argv[i], 0)) < 0){ if((fd = open(argv[i], 0)) < 0) {
printf("wc: cannot open %s\n", argv[i]); printf("wc: cannot open %s\n", argv[i]);
exit(1); exit(1);
} }