Пример #1
0
int
cgbfree(struct uufsd *disk, ufs2_daddr_t bno, long size)
{
	u_int8_t *blksfree;
	struct fs *fs;
	struct cg *cgp;
	ufs1_daddr_t fragno, cgbno;
	int i, cg, blk, frags, bbase;

	fs = &disk->d_fs;
	cg = dtog(fs, bno);
	if (cgread1(disk, cg) != 1)
		return (-1);
	cgp = &disk->d_cg;
	cgbno = dtogd(fs, bno);
	blksfree = cg_blksfree(cgp);
	if (size == fs->fs_bsize) {
		fragno = fragstoblks(fs, cgbno);
		ffs_setblock(fs, blksfree, fragno);
		ffs_clusteracct(fs, cgp, fragno, 1);
		cgp->cg_cs.cs_nbfree++;
		fs->fs_cstotal.cs_nbfree++;
		fs->fs_cs(fs, cg).cs_nbfree++;
	} else {
		bbase = cgbno - fragnum(fs, cgbno);
		/*
		 * decrement the counts associated with the old frags
		 */
		blk = blkmap(fs, blksfree, bbase);
		ffs_fragacct(fs, blk, cgp->cg_frsum, -1);
		/*
		 * deallocate the fragment
		 */
		frags = numfrags(fs, size);
		for (i = 0; i < frags; i++)
			setbit(blksfree, cgbno + i);
		cgp->cg_cs.cs_nffree += i;
		fs->fs_cstotal.cs_nffree += i;
		fs->fs_cs(fs, cg).cs_nffree += i;
		/*
		 * add back in counts associated with the new frags
		 */
		blk = blkmap(fs, blksfree, bbase);
		ffs_fragacct(fs, blk, cgp->cg_frsum, 1);
		/*
		 * if a complete block has been reassembled, account for it
		 */
		fragno = fragstoblks(fs, bbase);
		if (ffs_isblock(fs, blksfree, fragno)) {
			cgp->cg_cs.cs_nffree -= fs->fs_frag;
			fs->fs_cstotal.cs_nffree -= fs->fs_frag;
			fs->fs_cs(fs, cg).cs_nffree -= fs->fs_frag;
			ffs_clusteracct(fs, cgp, fragno, 1);
			cgp->cg_cs.cs_nbfree++;
			fs->fs_cstotal.cs_nbfree++;
			fs->fs_cs(fs, cg).cs_nbfree++;
		}
	}
	return cgwrite(disk);
}
/*
 * Allocate a block in a cylinder group.
 *
 * This algorithm implements the following policy:
 *   1) allocate the requested block.
 *   2) allocate a rotationally optimal block in the same cylinder.
 *   3) allocate the next available block on the block rotor for the
 *      specified cylinder group.
 * Note that this routine only allocates fs_bsize blocks; these
 * blocks may be fragmented by the routine that allocates them.
 */
static daddr_t
ffs_alloccgblk(struct inode *ip, struct buf *bp, daddr_t bpref)
{
	struct cg *cgp;
	daddr_t blkno;
	int32_t bno;
	struct fs *fs = ip->i_fs;
	const int needswap = UFS_FSNEEDSWAP(fs);
	u_int8_t *blksfree;

	cgp = (struct cg *)bp->b_data;
	blksfree = cg_blksfree(cgp, needswap);
	if (bpref == 0 || dtog(fs, bpref) != ufs_rw32(cgp->cg_cgx, needswap)) {
		bpref = ufs_rw32(cgp->cg_rotor, needswap);
	} else {
		bpref = ffs_blknum(fs, bpref);
		bno = dtogd(fs, bpref);
		/*
		 * if the requested block is available, use it
		 */
		if (ffs_isblock(fs, blksfree, ffs_fragstoblks(fs, bno)))
			goto gotit;
	}
	/*
	 * Take the next available one in this cylinder group.
	 */
	bno = ffs_mapsearch(fs, cgp, bpref, (int)fs->fs_frag);
	if (bno < 0)
		return (0);
	cgp->cg_rotor = ufs_rw32(bno, needswap);
gotit:
	blkno = ffs_fragstoblks(fs, bno);
	ffs_clrblock(fs, blksfree, (long)blkno);
	ffs_clusteracct(fs, cgp, blkno, -1);
	ufs_add32(cgp->cg_cs.cs_nbfree, -1, needswap);
	fs->fs_cstotal.cs_nbfree--;
	fs->fs_cs(fs, ufs_rw32(cgp->cg_cgx, needswap)).cs_nbfree--;
	fs->fs_fmod = 1;
	blkno = ufs_rw32(cgp->cg_cgx, needswap) * fs->fs_fpg + bno;
	return (blkno);
}
Пример #3
0
ufs2_daddr_t
cgballoc(struct uufsd *disk)
{
	u_int8_t *blksfree;
	struct cg *cgp;
	struct fs *fs;
	long bno;

	fs = &disk->d_fs;
	cgp = &disk->d_cg;
	blksfree = cg_blksfree(cgp);
	for (bno = 0; bno < fs->fs_fpg / fs->fs_frag; bno++)
		if (ffs_isblock(fs, blksfree, bno))
			goto gotit;
	return (0);
gotit:
	fs->fs_cs(fs, cgp->cg_cgx).cs_nbfree--;
	ffs_clrblock(fs, blksfree, (long)bno);
	ffs_clusteracct(fs, cgp, bno, -1);
	cgp->cg_cs.cs_nbfree--;
	fs->fs_cstotal.cs_nbfree--;
	fs->fs_fmod = 1;
	return (cgbase(fs, cgp->cg_cgx) + blkstofrags(fs, bno));
}
/*
 * Free a block or fragment.
 *
 * The specified block or fragment is placed back in the
 * free map. If a fragment is deallocated, a possible 
 * block reassembly is checked.
 */
void
ffs_blkfree(struct inode *ip, daddr_t bno, long size)
{
	struct cg *cgp;
	struct buf *bp;
	int32_t fragno, cgbno;
	int i, error, cg, blk, frags, bbase;
	struct fs *fs = ip->i_fs;
	const int needswap = UFS_FSNEEDSWAP(fs);

	if (size > fs->fs_bsize || ffs_fragoff(fs, size) != 0 ||
	    ffs_fragnum(fs, bno) + ffs_numfrags(fs, size) > fs->fs_frag) {
		errx(1, "blkfree: bad size: bno %lld bsize %d size %ld",
		    (long long)bno, fs->fs_bsize, size);
	}
	cg = dtog(fs, bno);
	if (bno >= fs->fs_size) {
		warnx("bad block %lld, ino %llu", (long long)bno,
		    (unsigned long long)ip->i_number);
		return;
	}
	error = bread(ip->i_devvp, FFS_FSBTODB(fs, cgtod(fs, cg)),
	    (int)fs->fs_cgsize, 0, &bp);
	if (error) {
		brelse(bp, 0);
		return;
	}
	cgp = (struct cg *)bp->b_data;
	if (!cg_chkmagic(cgp, needswap)) {
		brelse(bp, 0);
		return;
	}
	cgbno = dtogd(fs, bno);
	if (size == fs->fs_bsize) {
		fragno = ffs_fragstoblks(fs, cgbno);
		if (!ffs_isfreeblock(fs, cg_blksfree(cgp, needswap), fragno)) {
			errx(1, "blkfree: freeing free block %lld",
			    (long long)bno);
		}
		ffs_setblock(fs, cg_blksfree(cgp, needswap), fragno);
		ffs_clusteracct(fs, cgp, fragno, 1);
		ufs_add32(cgp->cg_cs.cs_nbfree, 1, needswap);
		fs->fs_cstotal.cs_nbfree++;
		fs->fs_cs(fs, cg).cs_nbfree++;
	} else {
		bbase = cgbno - ffs_fragnum(fs, cgbno);
		/*
		 * decrement the counts associated with the old frags
		 */
		blk = blkmap(fs, cg_blksfree(cgp, needswap), bbase);
		ffs_fragacct(fs, blk, cgp->cg_frsum, -1, needswap);
		/*
		 * deallocate the fragment
		 */
		frags = ffs_numfrags(fs, size);
		for (i = 0; i < frags; i++) {
			if (isset(cg_blksfree(cgp, needswap), cgbno + i)) {
				errx(1, "blkfree: freeing free frag: block %lld",
				    (long long)(cgbno + i));
			}
			setbit(cg_blksfree(cgp, needswap), cgbno + i);
		}
		ufs_add32(cgp->cg_cs.cs_nffree, i, needswap);
		fs->fs_cstotal.cs_nffree += i;
		fs->fs_cs(fs, cg).cs_nffree += i;
		/*
		 * add back in counts associated with the new frags
		 */
		blk = blkmap(fs, cg_blksfree(cgp, needswap), bbase);
		ffs_fragacct(fs, blk, cgp->cg_frsum, 1, needswap);
		/*
		 * if a complete block has been reassembled, account for it
		 */
		fragno = ffs_fragstoblks(fs, bbase);
		if (ffs_isblock(fs, cg_blksfree(cgp, needswap), fragno)) {
			ufs_add32(cgp->cg_cs.cs_nffree, -fs->fs_frag, needswap);
			fs->fs_cstotal.cs_nffree -= fs->fs_frag;
			fs->fs_cs(fs, cg).cs_nffree -= fs->fs_frag;
			ffs_clusteracct(fs, cgp, fragno, 1);
			ufs_add32(cgp->cg_cs.cs_nbfree, 1, needswap);
			fs->fs_cstotal.cs_nbfree++;
			fs->fs_cs(fs, cg).cs_nbfree++;
		}
	}
	fs->fs_fmod = 1;
	bdwrite(bp);
}