various cleanups
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rsc
parent
b6095304b7
commit
7d4aef6cfd
1 changed files with 43 additions and 56 deletions
99
fs.c
99
fs.c
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@ -41,13 +41,9 @@ iinit(void)
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static uint
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balloc(uint dev)
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{
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int b;
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int b, bi, m, ninodes, size;
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struct buf *bp;
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struct superblock *sb;
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int bi = 0;
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int size;
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int ninodes;
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uchar m;
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bp = bread(dev, 1);
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sb = (struct superblock*) bp->data;
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@ -62,16 +58,13 @@ balloc(uint dev)
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bi = b % BPB;
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m = 0x1 << (bi % 8);
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if((bp->data[bi/8] & m) == 0) { // is block free?
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break;
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bp->data[bi/8] |= 0x1 << (bi % 8);
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bwrite(bp, BBLOCK(b, ninodes)); // mark it allocated on disk
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brelse(bp);
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return b;
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}
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}
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if(b >= size)
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panic("balloc: out of blocks");
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bp->data[bi/8] |= 0x1 << (bi % 8);
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bwrite(bp, BBLOCK(b, ninodes)); // mark it allocated on disk
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brelse(bp);
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return b;
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panic("balloc: out of blocks");
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}
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// Free a disk block.
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@ -80,9 +73,7 @@ bfree(int dev, uint b)
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{
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struct buf *bp;
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struct superblock *sb;
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int bi;
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int ninodes;
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uchar m;
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int bi, m, ninodes;
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bp = bread(dev, 1);
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sb = (struct superblock*) bp->data;
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@ -96,8 +87,8 @@ bfree(int dev, uint b)
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bp = bread(dev, BBLOCK(b, ninodes));
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bi = b % BPB;
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m = ~(0x1 << (bi %8));
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bp->data[bi/8] &= m;
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m = 0x1 << (bi % 8);
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bp->data[bi/8] &= ~m;
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bwrite(bp, BBLOCK(b, ninodes)); // mark it free on disk
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brelse(bp);
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}
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@ -176,7 +167,7 @@ iupdate(struct inode *ip)
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dip->nlink = ip->nlink;
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dip->size = ip->size;
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memmove(dip->addrs, ip->addrs, sizeof(ip->addrs));
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bwrite(bp, IBLOCK(ip->inum)); // mark it allocated on the disk
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bwrite(bp, IBLOCK(ip->inum));
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brelse(bp);
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}
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@ -186,7 +177,7 @@ struct inode*
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ialloc(uint dev, short type)
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{
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struct inode *ip;
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struct dinode *dip = 0;
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struct dinode *dip;
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struct superblock *sb;
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int ninodes;
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int inum;
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@ -290,12 +281,13 @@ itrunc(struct inode *ip)
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{
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int i, j;
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struct buf *inbp;
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uint *a;
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for(i = 0; i < NADDRS; i++) {
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if(ip->addrs[i] != 0) {
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if(i == INDIRECT) {
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inbp = bread(ip->dev, ip->addrs[INDIRECT]);
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uint *a = (uint*) inbp->data;
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a = (uint*)inbp->data;
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for(j = 0; j < NINDIRECT; j++) {
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if(a[j] != 0) {
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bfree(ip->dev, a[j]);
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@ -372,7 +364,7 @@ stati(struct inode *ip, struct stat *st)
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int
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readi(struct inode *ip, char *dst, uint off, uint n)
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{
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uint target = n, n1;
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uint target, n1;
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struct buf *bp;
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if(ip->type == T_DEV) {
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@ -381,6 +373,7 @@ readi(struct inode *ip, char *dst, uint off, uint n)
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return devsw[ip->major].read(ip->minor, dst, n);
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}
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target = n;
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while(n > 0 && off < ip->size){
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bp = bread(ip->dev, bmap(ip, off / BSIZE));
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n1 = min(n, ip->size - off);
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@ -435,45 +428,39 @@ newblock(struct inode *ip, uint lbn)
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int
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writei(struct inode *ip, char *addr, uint off, uint n)
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{
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struct buf *bp;
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int r, m, lbn;
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if(ip->type == T_DEV) {
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if(ip->major < 0 || ip->major >= NDEV || !devsw[ip->major].write)
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return -1;
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return devsw[ip->major].write(ip->minor, addr, n);
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} else if(ip->type == T_FILE || ip->type == T_DIR) {
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struct buf *bp;
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int r = 0;
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int m;
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int lbn;
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while(r < n) {
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lbn = off / BSIZE;
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if(lbn >= MAXFILE)
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return r;
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if(newblock(ip, lbn) < 0) {
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cprintf("newblock failed\n");
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return r;
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}
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m = min(BSIZE - off % BSIZE, n-r);
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bp = bread(ip->dev, bmap(ip, lbn));
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memmove(bp->data + off % BSIZE, addr, m);
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bwrite(bp, bmap(ip, lbn));
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brelse(bp);
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r += m;
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off += m;
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}
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if(r > 0) {
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if(off > ip->size) {
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if(ip->type == T_DIR)
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ip->size = ((off / BSIZE) + 1) * BSIZE;
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else
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ip->size = off;
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}
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iupdate(ip);
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}
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return r;
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} else {
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panic("writei: unknown type");
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return 0;
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}
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for(r=0; r<n; ) {
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lbn = off / BSIZE;
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if(lbn >= MAXFILE)
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return r;
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if(newblock(ip, lbn) < 0) {
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cprintf("newblock failed\n");
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return r;
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}
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m = min(BSIZE - off % BSIZE, n-r);
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bp = bread(ip->dev, bmap(ip, lbn));
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memmove(bp->data + off % BSIZE, addr, m);
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bwrite(bp, bmap(ip, lbn));
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brelse(bp);
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r += m;
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off += m;
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}
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if(r > 0 && off > ip->size) {
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if(ip->type == T_DIR)
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ip->size = ((off / BSIZE) + 1) * BSIZE;
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else
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ip->size = off;
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iupdate(ip);
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}
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return r;
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}
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// Skip over the next path element in path,
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