示例#1
0
/*
 * Truncate the inode oip to at most length size, freeing the
 * disk blocks.
 */
int
ffs_truncate(struct vnode *vp, off_t length, int flags, struct ucred *cred)
{
	struct vnode *ovp = vp;
	ufs_daddr_t lastblock;
	struct inode *oip;
	ufs_daddr_t bn, lbn, lastiblock[NIADDR], indir_lbn[NIADDR];
	ufs_daddr_t oldblks[NDADDR + NIADDR], newblks[NDADDR + NIADDR];
	struct fs *fs;
	struct buf *bp;
	int offset, size, level;
	long count, nblocks, blocksreleased = 0;
	int i;
	int aflags, error, allerror;
	off_t osize;

	oip = VTOI(ovp);
	fs = oip->i_fs;
	if (length < 0)
		return (EINVAL);
	if (length > fs->fs_maxfilesize)
		return (EFBIG);
	if (ovp->v_type == VLNK &&
	    (oip->i_size < ovp->v_mount->mnt_maxsymlinklen || oip->i_din.di_blocks == 0)) {
#ifdef DIAGNOSTIC
		if (length != 0)
			panic("ffs_truncate: partial truncate of symlink");
#endif /* DIAGNOSTIC */
		bzero((char *)&oip->i_shortlink, (uint)oip->i_size);
		oip->i_size = 0;
		oip->i_flag |= IN_CHANGE | IN_UPDATE;
		return (ffs_update(ovp, 1));
	}
	if (oip->i_size == length) {
		oip->i_flag |= IN_CHANGE | IN_UPDATE;
		return (ffs_update(ovp, 0));
	}
	if (fs->fs_ronly)
		panic("ffs_truncate: read-only filesystem");
#ifdef QUOTA
	error = ufs_getinoquota(oip);
	if (error)
		return (error);
#endif
	ovp->v_lasta = ovp->v_clen = ovp->v_cstart = ovp->v_lastw = 0;
	if (DOINGSOFTDEP(ovp)) {
		if (length > 0 || softdep_slowdown(ovp)) {
			/*
			 * If a file is only partially truncated, then
			 * we have to clean up the data structures
			 * describing the allocation past the truncation
			 * point. Finding and deallocating those structures
			 * is a lot of work. Since partial truncation occurs
			 * rarely, we solve the problem by syncing the file
			 * so that it will have no data structures left.
			 */
			if ((error = VOP_FSYNC(ovp, MNT_WAIT, 0)) != 0)
				return (error);
		} else {
#ifdef QUOTA
			(void) ufs_chkdq(oip, -oip->i_blocks, NOCRED, 0);
#endif
			softdep_setup_freeblocks(oip, length);
			vinvalbuf(ovp, 0, 0, 0);
			nvnode_pager_setsize(ovp, 0, fs->fs_bsize, 0);
			oip->i_flag |= IN_CHANGE | IN_UPDATE;
			return (ffs_update(ovp, 0));
		}
	}
	osize = oip->i_size;

	/*
	 * Lengthen the size of the file. We must ensure that the
	 * last byte of the file is allocated. Since the smallest
	 * value of osize is 0, length will be at least 1.
	 *
	 * nvextendbuf() only breads the old buffer.  The blocksize
	 * of the new buffer must be specified so it knows how large
	 * to make the VM object.
	 */
	if (osize < length) {
		nvextendbuf(vp, osize, length,
			    blkoffsize(fs, oip, osize),	/* oblksize */
			    blkoffresize(fs, length),	/* nblksize */
			    blkoff(fs, osize),
			    blkoff(fs, length),
			    0);

		aflags = B_CLRBUF;
		if (flags & IO_SYNC)
			aflags |= B_SYNC;
		/* BALLOC will reallocate the fragment at the old EOF */
		error = VOP_BALLOC(ovp, length - 1, 1, cred, aflags, &bp);
		if (error)
			return (error);
		oip->i_size = length;
		if (bp->b_bufsize == fs->fs_bsize)
			bp->b_flags |= B_CLUSTEROK;
		if (aflags & B_SYNC)
			bwrite(bp);
		else
			bawrite(bp);
		oip->i_flag |= IN_CHANGE | IN_UPDATE;
		return (ffs_update(ovp, 1));
	}

	/*
	 * Shorten the size of the file.
	 *
	 * NOTE: The block size specified in nvtruncbuf() is the blocksize
	 *	 of the buffer containing length prior to any reallocation
	 *	 of the block.
	 */
	allerror = nvtruncbuf(ovp, length, blkoffsize(fs, oip, length),
			      blkoff(fs, length), 0);
	offset = blkoff(fs, length);
	if (offset == 0) {
		oip->i_size = length;
	} else {
		lbn = lblkno(fs, length);
		aflags = B_CLRBUF;
		if (flags & IO_SYNC)
			aflags |= B_SYNC;
		error = VOP_BALLOC(ovp, length - 1, 1, cred, aflags, &bp);
		if (error)
			return (error);

		/*
		 * When we are doing soft updates and the UFS_BALLOC
		 * above fills in a direct block hole with a full sized
		 * block that will be truncated down to a fragment below,
		 * we must flush out the block dependency with an FSYNC
		 * so that we do not get a soft updates inconsistency
		 * when we create the fragment below.
		 *
		 * nvtruncbuf() may have re-dirtied the underlying block
		 * as part of its truncation zeroing code.  To avoid a
		 * 'locking against myself' panic in the second fsync we
		 * can simply undirty the bp since the redirtying was
		 * related to areas of the buffer that we are going to
		 * throw away anyway, and we will b*write() the remainder
		 * anyway down below.
		 */
		if (DOINGSOFTDEP(ovp) && lbn < NDADDR &&
		    fragroundup(fs, blkoff(fs, length)) < fs->fs_bsize) {
			bundirty(bp);
			error = VOP_FSYNC(ovp, MNT_WAIT, 0);
			if (error) {
				bdwrite(bp);
				return (error);
			}
		}
		oip->i_size = length;
		size = blksize(fs, oip, lbn);
#if 0
		/* remove - nvtruncbuf deals with this */
		if (ovp->v_type != VDIR)
			bzero((char *)bp->b_data + offset,
			    (uint)(size - offset));
#endif
		/* Kirk's code has reallocbuf(bp, size, 1) here */
		allocbuf(bp, size);
		if (bp->b_bufsize == fs->fs_bsize)
			bp->b_flags |= B_CLUSTEROK;
		if (aflags & B_SYNC)
			bwrite(bp);
		else
			bawrite(bp);
	}
	/*
	 * Calculate index into inode's block list of
	 * last direct and indirect blocks (if any)
	 * which we want to keep.  Lastblock is -1 when
	 * the file is truncated to 0.
	 */
	lastblock = lblkno(fs, length + fs->fs_bsize - 1) - 1;
	lastiblock[SINGLE] = lastblock - NDADDR;
	lastiblock[DOUBLE] = lastiblock[SINGLE] - NINDIR(fs);
	lastiblock[TRIPLE] = lastiblock[DOUBLE] - NINDIR(fs) * NINDIR(fs);
	nblocks = btodb(fs->fs_bsize);

	/*
	 * Update file and block pointers on disk before we start freeing
	 * blocks.  If we crash before free'ing blocks below, the blocks
	 * will be returned to the free list.  lastiblock values are also
	 * normalized to -1 for calls to ffs_indirtrunc below.
	 */
	bcopy((caddr_t)&oip->i_db[0], (caddr_t)oldblks, sizeof oldblks);
	for (level = TRIPLE; level >= SINGLE; level--)
		if (lastiblock[level] < 0) {
			oip->i_ib[level] = 0;
			lastiblock[level] = -1;
		}
	for (i = NDADDR - 1; i > lastblock; i--)
		oip->i_db[i] = 0;
	oip->i_flag |= IN_CHANGE | IN_UPDATE;
	error = ffs_update(ovp, 1);
	if (error && allerror == 0)
		allerror = error;
	
	/*
	 * Having written the new inode to disk, save its new configuration
	 * and put back the old block pointers long enough to process them.
	 * Note that we save the new block configuration so we can check it
	 * when we are done.
	 */
	bcopy((caddr_t)&oip->i_db[0], (caddr_t)newblks, sizeof newblks);
	bcopy((caddr_t)oldblks, (caddr_t)&oip->i_db[0], sizeof oldblks);
	oip->i_size = osize;

	if (error && allerror == 0)
		allerror = error;

	/*
	 * Indirect blocks first.
	 */
	indir_lbn[SINGLE] = -NDADDR;
	indir_lbn[DOUBLE] = indir_lbn[SINGLE] - NINDIR(fs) - 1;
	indir_lbn[TRIPLE] = indir_lbn[DOUBLE] - NINDIR(fs) * NINDIR(fs) - 1;
	for (level = TRIPLE; level >= SINGLE; level--) {
		bn = oip->i_ib[level];
		if (bn != 0) {
			error = ffs_indirtrunc(oip, indir_lbn[level],
			    fsbtodb(fs, bn), lastiblock[level], level, &count);
			if (error)
				allerror = error;
			blocksreleased += count;
			if (lastiblock[level] < 0) {
				oip->i_ib[level] = 0;
				ffs_blkfree(oip, bn, fs->fs_bsize);
				blocksreleased += nblocks;
			}
		}
		if (lastiblock[level] >= 0)
			goto done;
	}

	/*
	 * All whole direct blocks or frags.
	 */
	for (i = NDADDR - 1; i > lastblock; i--) {
		long bsize;

		bn = oip->i_db[i];
		if (bn == 0)
			continue;
		oip->i_db[i] = 0;
		bsize = blksize(fs, oip, i);
		ffs_blkfree(oip, bn, bsize);
		blocksreleased += btodb(bsize);
	}
	if (lastblock < 0)
		goto done;

	/*
	 * Finally, look for a change in size of the
	 * last direct block; release any frags.
	 */
	bn = oip->i_db[lastblock];
	if (bn != 0) {
		long oldspace, newspace;

		/*
		 * Calculate amount of space we're giving
		 * back as old block size minus new block size.
		 */
		oldspace = blksize(fs, oip, lastblock);
		oip->i_size = length;
		newspace = blksize(fs, oip, lastblock);
		if (newspace == 0)
			panic("ffs_truncate: newspace");
		if (oldspace - newspace > 0) {
			/*
			 * Block number of space to be free'd is
			 * the old block # plus the number of frags
			 * required for the storage we're keeping.
			 */
			bn += numfrags(fs, newspace);
			ffs_blkfree(oip, bn, oldspace - newspace);
			blocksreleased += btodb(oldspace - newspace);
		}
	}
done:
#ifdef DIAGNOSTIC
	for (level = SINGLE; level <= TRIPLE; level++)
		if (newblks[NDADDR + level] != oip->i_ib[level])
			panic("ffs_truncate1");
	for (i = 0; i < NDADDR; i++)
		if (newblks[i] != oip->i_db[i])
			panic("ffs_truncate2");
	if (length == 0 && !RB_EMPTY(&ovp->v_rbdirty_tree))
		panic("ffs_truncate3");
#endif /* DIAGNOSTIC */
	/*
	 * Put back the real size.
	 */
	oip->i_size = length;
	oip->i_blocks -= blocksreleased;

	if (oip->i_blocks < 0)			/* sanity */
		oip->i_blocks = 0;
	oip->i_flag |= IN_CHANGE;
#ifdef QUOTA
	(void) ufs_chkdq(oip, -blocksreleased, NOCRED, 0);
#endif
	return (allerror);
}
示例#2
0
/*
 * Release blocks associated with the inode ip and stored in the indirect
 * block bn.  Blocks are free'd in LIFO order up to (but not including)
 * lastbn.  If level is greater than SINGLE, the block is an indirect block
 * and recursive calls to indirtrunc must be used to cleanse other indirect
 * blocks.
 *
 * NB: triple indirect blocks are untested.
 */
static int
ffs_indirtrunc(struct inode *ip, ufs_daddr_t lbn, ufs_daddr_t dbn,
	       ufs_daddr_t lastbn, int level, long *countp)
{
	int i;
	struct buf *bp;
	struct fs *fs = ip->i_fs;
	ufs_daddr_t *bap;
	struct vnode *vp;
	ufs_daddr_t *copy = NULL, nb, nlbn, last;
	long blkcount, factor;
	int nblocks, blocksreleased = 0;
	int error = 0, allerror = 0;

	/*
	 * Calculate index in current block of last
	 * block to be kept.  -1 indicates the entire
	 * block so we need not calculate the index.
	 */
	factor = 1;
	for (i = SINGLE; i < level; i++)
		factor *= NINDIR(fs);
	last = lastbn;
	if (lastbn > 0)
		last /= factor;
	nblocks = btodb(fs->fs_bsize);
	/*
	 * Get buffer of block pointers, zero those entries corresponding
	 * to blocks to be free'd, and update on disk copy first.  Since
	 * double(triple) indirect before single(double) indirect, calls
	 * to bmap on these blocks will fail.  However, we already have
	 * the on disk address, so we have to set the bio_offset field
	 * explicitly instead of letting bread do everything for us.
	 */
	vp = ITOV(ip);
	bp = getblk(vp, lblktodoff(fs, lbn), (int)fs->fs_bsize, 0, 0);
	if ((bp->b_flags & B_CACHE) == 0) {
		bp->b_flags &= ~(B_ERROR|B_INVAL);
		bp->b_cmd = BUF_CMD_READ;
		if (bp->b_bcount > bp->b_bufsize)
			panic("ffs_indirtrunc: bad buffer size");
		/*
		 * BIO is bio2 which chains back to bio1.  We wait
		 * on bio1.
		 */
		bp->b_bio2.bio_offset = dbtodoff(fs, dbn);
		bp->b_bio1.bio_done = biodone_sync;
		bp->b_bio1.bio_flags |= BIO_SYNC;
		vfs_busy_pages(vp, bp);
		/*
		 * Access the block device layer using the device vnode
		 * and the translated block number (bio2) instead of the
		 * file vnode (vp) and logical block number (bio1).
		 *
		 * Even though we are bypassing the vnode layer, we still
		 * want the vnode state to indicate that an I/O on its behalf
		 * is in progress.
		 */
		bio_start_transaction(&bp->b_bio1, &vp->v_track_read);
		vn_strategy(ip->i_devvp, &bp->b_bio2);
		error = biowait(&bp->b_bio1, "biord");
	}
	if (error) {
		brelse(bp);
		*countp = 0;
		return (error);
	}

	bap = (ufs_daddr_t *)bp->b_data;
	if (lastbn != -1) {
		copy = kmalloc(fs->fs_bsize, M_TEMP, M_WAITOK);
		bcopy((caddr_t)bap, (caddr_t)copy, (uint)fs->fs_bsize);
		bzero((caddr_t)&bap[last + 1],
		    (uint)(NINDIR(fs) - (last + 1)) * sizeof (ufs_daddr_t));
		if (DOINGASYNC(vp)) {
			bawrite(bp);
		} else {
			error = bwrite(bp);
			if (error)
				allerror = error;
		}
		bap = copy;
	}

	/*
	 * Recursively free totally unused blocks.
	 */
	for (i = NINDIR(fs) - 1, nlbn = lbn + 1 - i * factor; i > last;
	    i--, nlbn += factor) {
		nb = bap[i];
		if (nb == 0)
			continue;
		if (level > SINGLE) {
			if ((error = ffs_indirtrunc(ip, nlbn, fsbtodb(fs, nb),
			    (ufs_daddr_t)-1, level - 1, &blkcount)) != 0)
				allerror = error;
			blocksreleased += blkcount;
		}
		ffs_blkfree(ip, nb, fs->fs_bsize);
		blocksreleased += nblocks;
	}

	/*
	 * Recursively free last partial block.
	 */
	if (level > SINGLE && lastbn >= 0) {
		last = lastbn % factor;
		nb = bap[i];
		if (nb != 0) {
			error = ffs_indirtrunc(ip, nlbn, fsbtodb(fs, nb),
			    last, level - 1, &blkcount);
			if (error)
				allerror = error;
			blocksreleased += blkcount;
		}
	}
	if (copy != NULL) {
		kfree(copy, M_TEMP);
	} else {
		bp->b_flags |= B_INVAL | B_NOCACHE;
		brelse(bp);
	}
		
	*countp = blocksreleased;
	return (allerror);
}
示例#3
0
/*
 * Release blocks associated with the inode ip and stored in the indirect
 * block bn.  Blocks are free'd in LIFO order up to (but not including)
 * lastbn.  If level is greater than SINGLE, the block is an indirect block
 * and recursive calls to indirtrunc must be used to cleanse other indirect
 * blocks.
 *
 * NB: triple indirect blocks are untested.
 */
int
ffs_indirtrunc(struct inode *ip, daddr64_t lbn, daddr64_t dbn,
    daddr64_t lastbn, int level, long *countp)
{
	int i;
	struct buf *bp;
	struct fs *fs = ip->i_fs;
	struct vnode *vp;
	void *copy = NULL;
	daddr64_t nb, nlbn, last;
	long blkcount, factor;
	int nblocks, blocksreleased = 0;
	int error = 0, allerror = 0;
	int32_t *bap1 = NULL;
#ifdef FFS2
	int64_t *bap2 = NULL;
#endif

	/*
	 * Calculate index in current block of last
	 * block to be kept.  -1 indicates the entire
	 * block so we need not calculate the index.
	 */
	factor = 1;
	for (i = SINGLE; i < level; i++)
		factor *= NINDIR(fs);
	last = lastbn;
	if (lastbn > 0)
		last /= factor;
	nblocks = btodb(fs->fs_bsize);
	/*
	 * Get buffer of block pointers, zero those entries corresponding
	 * to blocks to be free'd, and update on disk copy first.  Since
	 * double(triple) indirect before single(double) indirect, calls
	 * to bmap on these blocks will fail.  However, we already have
	 * the on disk address, so we have to set the b_blkno field
	 * explicitly instead of letting bread do everything for us.
	 */
	vp = ITOV(ip);
	bp = getblk(vp, lbn, (int)fs->fs_bsize, 0, 0);
	if (!(bp->b_flags & (B_DONE | B_DELWRI))) {
		curproc->p_ru.ru_inblock++;		/* pay for read */
		bcstats.pendingreads++;
		bcstats.numreads++;
		bp->b_flags |= B_READ;
		if (bp->b_bcount > bp->b_bufsize)
			panic("ffs_indirtrunc: bad buffer size");
		bp->b_blkno = dbn;
		VOP_STRATEGY(bp);
		error = biowait(bp);
	}
	if (error) {
		brelse(bp);
		*countp = 0;
		return (error);
	}

#ifdef FFS2
	if (ip->i_ump->um_fstype == UM_UFS2)
		bap2 = (int64_t *)bp->b_data;
	else
#endif
		bap1 = (int32_t *)bp->b_data;

	if (lastbn != -1) {
		copy = malloc(fs->fs_bsize, M_TEMP, M_WAITOK);
		bcopy(bp->b_data, copy, (u_int) fs->fs_bsize);

		for (i = last + 1; i < NINDIR(fs); i++)
			BAP_ASSIGN(ip, i, 0);

		if (!DOINGASYNC(vp)) {
			error = bwrite(bp);
			if (error)
				allerror = error;
		} else {
			bawrite(bp);
		}

#ifdef FFS2
		if (ip->i_ump->um_fstype == UM_UFS2)
			bap2 = (int64_t *)copy;
		else
#endif
			bap1 = (int32_t *)copy;
	}

	/*
	 * Recursively free totally unused blocks.
	 */
	for (i = NINDIR(fs) - 1, nlbn = lbn + 1 - i * factor; i > last;
	    i--, nlbn += factor) {
		nb = BAP(ip, i);
		if (nb == 0)
			continue;
		if (level > SINGLE) {
			error = ffs_indirtrunc(ip, nlbn, fsbtodb(fs, nb),
					       (daddr64_t)-1, level - 1,
					       &blkcount);
			if (error)
				allerror = error;
			blocksreleased += blkcount;
		}
		ffs_blkfree(ip, nb, fs->fs_bsize);
		blocksreleased += nblocks;
	}

	/*
	 * Recursively free last partial block.
	 */
	if (level > SINGLE && lastbn >= 0) {
		last = lastbn % factor;
		nb = BAP(ip, i);
		if (nb != 0) {
			error = ffs_indirtrunc(ip, nlbn, fsbtodb(fs, nb),
					       last, level - 1, &blkcount);
			if (error)
				allerror = error;
			blocksreleased += blkcount;
		}
	}
	if (copy != NULL) {
		free(copy, M_TEMP);
	} else {
		bp->b_flags |= B_INVAL;
		brelse(bp);
	}
		
	*countp = blocksreleased;
	return (allerror);
}
示例#4
0
/*
 * Truncate the inode oip to at most length size, freeing the
 * disk blocks.
 */
int
ffs_truncate(struct inode *oip, off_t length, int flags, struct ucred *cred)
{
	struct vnode *ovp;
	daddr64_t lastblock;
	daddr64_t bn, lbn, lastiblock[NIADDR], indir_lbn[NIADDR];
	daddr64_t oldblks[NDADDR + NIADDR], newblks[NDADDR + NIADDR];
	struct fs *fs;
	struct buf *bp;
	int offset, size, level;
	long count, nblocks, vflags, blocksreleased = 0;
	int i, aflags, error, allerror, indirect = 0;
	off_t osize;
	extern int num_indirdep;
	extern int max_indirdep;

	if (length < 0)
		return (EINVAL);
	ovp = ITOV(oip);

	if (ovp->v_type != VREG &&
	    ovp->v_type != VDIR &&
	    ovp->v_type != VLNK)
		return (0);

	if (DIP(oip, size) == length)
		return (0);

	if (ovp->v_type == VLNK &&
	    (DIP(oip, size) < ovp->v_mount->mnt_maxsymlinklen ||
	     (ovp->v_mount->mnt_maxsymlinklen == 0 &&
	      oip->i_din1->di_blocks == 0))) {
#ifdef DIAGNOSTIC
		if (length != 0)
			panic("ffs_truncate: partial truncate of symlink");
#endif
		memset(SHORTLINK(oip), 0, (size_t) DIP(oip, size));
		DIP_ASSIGN(oip, size, 0);
		oip->i_flag |= IN_CHANGE | IN_UPDATE;
		return (UFS_UPDATE(oip, MNT_WAIT));
	}

	if ((error = getinoquota(oip)) != 0)
		return (error);

	uvm_vnp_setsize(ovp, length);
	oip->i_ci.ci_lasta = oip->i_ci.ci_clen 
	    = oip->i_ci.ci_cstart = oip->i_ci.ci_lastw = 0;

	if (DOINGSOFTDEP(ovp)) {
		if (length > 0 || softdep_slowdown(ovp)) {
			/*
			 * If a file is only partially truncated, then
			 * we have to clean up the data structures
			 * describing the allocation past the truncation
			 * point. Finding and deallocating those structures
			 * is a lot of work. Since partial truncation occurs
			 * rarely, we solve the problem by syncing the file
			 * so that it will have no data structures left.
			 */
			if ((error = VOP_FSYNC(ovp, cred, MNT_WAIT)) != 0)
				return (error);
		} else {
			(void)ufs_quota_free_blocks(oip, DIP(oip, blocks),
			    NOCRED);
			softdep_setup_freeblocks(oip, length);
			(void) vinvalbuf(ovp, 0, cred, curproc, 0, 0);
			oip->i_flag |= IN_CHANGE | IN_UPDATE;
			return (UFS_UPDATE(oip, 0));
		}
	}

	fs = oip->i_fs;
	osize = DIP(oip, size);
	/*
	 * Lengthen the size of the file. We must ensure that the
	 * last byte of the file is allocated. Since the smallest
	 * value of osize is 0, length will be at least 1.
	 */
	if (osize < length) {
		if (length > fs->fs_maxfilesize)
			return (EFBIG);
		aflags = B_CLRBUF;
		if (flags & IO_SYNC)
			aflags |= B_SYNC;
		error = UFS_BUF_ALLOC(oip, length - 1, 1, 
				   cred, aflags, &bp);
		if (error)
			return (error);
		if (bp->b_lblkno >= NDADDR)
			indirect = 1;
		DIP_ASSIGN(oip, size, length);
		uvm_vnp_setsize(ovp, length);
		(void) uvm_vnp_uncache(ovp);
		if (aflags & B_SYNC)
			bwrite(bp);
		else
			bawrite(bp);
		oip->i_flag |= IN_CHANGE | IN_UPDATE;
		error = UFS_UPDATE(oip, MNT_WAIT);
		if (DOINGSOFTDEP(ovp) && num_indirdep > max_indirdep)
			if (indirect) {
				/*
				 * If the number of pending indirect block
				 * dependencies is sufficiently close to the
				 * maximum number of simultaneously mappable
				 * buffers force a sync on the vnode to prevent
				 * buffer cache exhaustion.
				 */
				VOP_FSYNC(ovp, curproc->p_ucred, MNT_WAIT);
			}
		return (error);
	}
	uvm_vnp_setsize(ovp, length);

	/*
	 * Shorten the size of the file. If the file is not being
	 * truncated to a block boundary, the contents of the
	 * partial block following the end of the file must be
	 * zero'ed in case it ever becomes accessible again because
	 * of subsequent file growth. Directories however are not
	 * zero'ed as they should grow back initialized to empty.
	 */
	offset = blkoff(fs, length);
	if (offset == 0) {
		DIP_ASSIGN(oip, size, length);
	} else {
		lbn = lblkno(fs, length);
		aflags = B_CLRBUF;
		if (flags & IO_SYNC)
			aflags |= B_SYNC;
		error = UFS_BUF_ALLOC(oip, length - 1, 1,
				   cred, aflags, &bp);
		if (error)
			return (error);
		/*
		 * When we are doing soft updates and the UFS_BALLOC
		 * above fills in a direct block hole with a full sized
		 * block that will be truncated down to a fragment below,
		 * we must flush out the block dependency with an FSYNC
		 * so that we do not get a soft updates inconsistency
		 * when we create the fragment below.
		 */
		if (DOINGSOFTDEP(ovp) && lbn < NDADDR &&
		    fragroundup(fs, blkoff(fs, length)) < fs->fs_bsize &&
		    (error = VOP_FSYNC(ovp, cred, MNT_WAIT)) != 0)
			return (error);
		DIP_ASSIGN(oip, size, length);
		size = blksize(fs, oip, lbn);
		(void) uvm_vnp_uncache(ovp);
		if (ovp->v_type != VDIR)
			bzero((char *)bp->b_data + offset,
			      (u_int)(size - offset));
		bp->b_bcount = size;
		if (aflags & B_SYNC)
			bwrite(bp);
		else
			bawrite(bp);
	}
	/*
	 * Calculate index into inode's block list of
	 * last direct and indirect blocks (if any)
	 * which we want to keep.  Lastblock is -1 when
	 * the file is truncated to 0.
	 */
	lastblock = lblkno(fs, length + fs->fs_bsize - 1) - 1;
	lastiblock[SINGLE] = lastblock - NDADDR;
	lastiblock[DOUBLE] = lastiblock[SINGLE] - NINDIR(fs);
	lastiblock[TRIPLE] = lastiblock[DOUBLE] - NINDIR(fs) * NINDIR(fs);
	nblocks = btodb(fs->fs_bsize);

	/*
	 * Update file and block pointers on disk before we start freeing
	 * blocks.  If we crash before free'ing blocks below, the blocks
	 * will be returned to the free list.  lastiblock values are also
	 * normalized to -1 for calls to ffs_indirtrunc below.
	 */
	for (level = TRIPLE; level >= SINGLE; level--) {
		oldblks[NDADDR + level] = DIP(oip, ib[level]);
		if (lastiblock[level] < 0) {
			DIP_ASSIGN(oip, ib[level], 0);
			lastiblock[level] = -1;
		}
	}

	for (i = 0; i < NDADDR; i++) {
		oldblks[i] = DIP(oip, db[i]);
		if (i > lastblock)
			DIP_ASSIGN(oip, db[i], 0);
	}

	oip->i_flag |= IN_CHANGE | IN_UPDATE;
	if ((error = UFS_UPDATE(oip, MNT_WAIT)) != 0)
		allerror = error;

	/*
	 * Having written the new inode to disk, save its new configuration
	 * and put back the old block pointers long enough to process them.
	 * Note that we save the new block configuration so we can check it
	 * when we are done.
	 */
	for (i = 0; i < NDADDR; i++) {
		newblks[i] = DIP(oip, db[i]);
		DIP_ASSIGN(oip, db[i], oldblks[i]);
	}

	for (i = 0; i < NIADDR; i++) {
		newblks[NDADDR + i] = DIP(oip, ib[i]);
		DIP_ASSIGN(oip, ib[i], oldblks[NDADDR + i]);
	}

	DIP_ASSIGN(oip, size, osize);
	vflags = ((length > 0) ? V_SAVE : 0) | V_SAVEMETA;
	allerror = vinvalbuf(ovp, vflags, cred, curproc, 0, 0);

	/*
	 * Indirect blocks first.
	 */
	indir_lbn[SINGLE] = -NDADDR;
	indir_lbn[DOUBLE] = indir_lbn[SINGLE] - NINDIR(fs) - 1;
	indir_lbn[TRIPLE] = indir_lbn[DOUBLE] - NINDIR(fs) * NINDIR(fs) - 1;
	for (level = TRIPLE; level >= SINGLE; level--) {
		bn = DIP(oip, ib[level]);
		if (bn != 0) {
			error = ffs_indirtrunc(oip, indir_lbn[level],
			    fsbtodb(fs, bn), lastiblock[level], level, &count);
			if (error)
				allerror = error;
			blocksreleased += count;
			if (lastiblock[level] < 0) {
				DIP_ASSIGN(oip, ib[level], 0);
				ffs_blkfree(oip, bn, fs->fs_bsize);
				blocksreleased += nblocks;
			}
		}
		if (lastiblock[level] >= 0)
			goto done;
	}

	/*
	 * All whole direct blocks or frags.
	 */
	for (i = NDADDR - 1; i > lastblock; i--) {
		long bsize;

		bn = DIP(oip, db[i]);
		if (bn == 0)
			continue;

		DIP_ASSIGN(oip, db[i], 0);
		bsize = blksize(fs, oip, i);
		ffs_blkfree(oip, bn, bsize);
		blocksreleased += btodb(bsize);
	}
	if (lastblock < 0)
		goto done;

	/*
	 * Finally, look for a change in size of the
	 * last direct block; release any frags.
	 */
	bn = DIP(oip, db[lastblock]);
	if (bn != 0) {
		long oldspace, newspace;

		/*
		 * Calculate amount of space we're giving
		 * back as old block size minus new block size.
		 */
		oldspace = blksize(fs, oip, lastblock);
		DIP_ASSIGN(oip, size, length);
		newspace = blksize(fs, oip, lastblock);
		if (newspace == 0)
			panic("ffs_truncate: newspace");
		if (oldspace - newspace > 0) {
			/*
			 * Block number of space to be free'd is
			 * the old block # plus the number of frags
			 * required for the storage we're keeping.
			 */
			bn += numfrags(fs, newspace);
			ffs_blkfree(oip, bn, oldspace - newspace);
			blocksreleased += btodb(oldspace - newspace);
		}
	}
done:
#ifdef DIAGNOSTIC
	for (level = SINGLE; level <= TRIPLE; level++)
		if (newblks[NDADDR + level] != DIP(oip, ib[level]))
			panic("ffs_truncate1");
	for (i = 0; i < NDADDR; i++)
		if (newblks[i] != DIP(oip, db[i]))
			panic("ffs_truncate2");
#endif /* DIAGNOSTIC */
	/*
	 * Put back the real size.
	 */
	DIP_ASSIGN(oip, size, length);
	DIP_ADD(oip, blocks, -blocksreleased);
	oip->i_flag |= IN_CHANGE;
	(void)ufs_quota_free_blocks(oip, blocksreleased, NOCRED);
	return (allerror);
}
示例#5
0
/*
 * Release blocks associated with the inode ip and stored in the indirect
 * block bn.  Blocks are free'd in LIFO order up to (but not including)
 * lastbn.  If level is greater than SINGLE, the block is an indirect block
 * and recursive calls to indirtrunc must be used to cleanse other indirect
 * blocks.
 *
 * NB: triple indirect blocks are untested.
 */
static int
ffs_indirtrunc(struct inode *ip, daddr_t lbn, daddr_t dbn, daddr_t lastbn,
               int level, int64_t *countp)
{
    int i;
    struct buf *bp;
    struct fs *fs = ip->i_fs;
    int32_t *bap1 = NULL;
    int64_t *bap2 = NULL;
    struct vnode *vp;
    daddr_t nb, nlbn, last;
    char *copy = NULL;
    int64_t blkcount, factor, blocksreleased = 0;
    int nblocks;
    int error = 0, allerror = 0;
    const int needswap = UFS_FSNEEDSWAP(fs);
#define RBAP(ip, i) (((ip)->i_ump->um_fstype == UFS1) ? \
	    ufs_rw32(bap1[i], needswap) : ufs_rw64(bap2[i], needswap))
#define BAP_ASSIGN(ip, i, value)					\
	do {								\
		if ((ip)->i_ump->um_fstype == UFS1)			\
			bap1[i] = (value);				\
		else							\
			bap2[i] = (value);				\
	} while(0)

    /*
     * Calculate index in current block of last
     * block to be kept.  -1 indicates the entire
     * block so we need not calculate the index.
     */
    factor = 1;
    for (i = SINGLE; i < level; i++)
        factor *= FFS_NINDIR(fs);
    last = lastbn;
    if (lastbn > 0)
        last /= factor;
    nblocks = btodb(fs->fs_bsize);
    /*
     * Get buffer of block pointers, zero those entries corresponding
     * to blocks to be free'd, and update on disk copy first.  Since
     * double(triple) indirect before single(double) indirect, calls
     * to bmap on these blocks will fail.  However, we already have
     * the on disk address, so we have to set the b_blkno field
     * explicitly instead of letting bread do everything for us.
     */
    vp = ITOV(ip);
    error = ffs_getblk(vp, lbn, FFS_NOBLK, fs->fs_bsize, false, &bp);
    if (error) {
        *countp = 0;
        return error;
    }
    if (bp->b_oflags & (BO_DONE | BO_DELWRI)) {
        /* Braces must be here in case trace evaluates to nothing. */
        trace(TR_BREADHIT, pack(vp, fs->fs_bsize), lbn);
    } else {
        trace(TR_BREADMISS, pack(vp, fs->fs_bsize), lbn);
        curlwp->l_ru.ru_inblock++;	/* pay for read */
        bp->b_flags |= B_READ;
        bp->b_flags &= ~B_COWDONE;	/* we change blkno below */
        if (bp->b_bcount > bp->b_bufsize)
            panic("ffs_indirtrunc: bad buffer size");
        bp->b_blkno = dbn;
        BIO_SETPRIO(bp, BPRIO_TIMECRITICAL);
        VOP_STRATEGY(vp, bp);
        error = biowait(bp);
        if (error == 0)
            error = fscow_run(bp, true);
    }
    if (error) {
        brelse(bp, 0);
        *countp = 0;
        return (error);
    }

    if (ip->i_ump->um_fstype == UFS1)
        bap1 = (int32_t *)bp->b_data;
    else
        bap2 = (int64_t *)bp->b_data;
    if (lastbn >= 0) {
        copy = kmem_alloc(fs->fs_bsize, KM_SLEEP);
        memcpy((void *)copy, bp->b_data, (u_int)fs->fs_bsize);
        for (i = last + 1; i < FFS_NINDIR(fs); i++)
            BAP_ASSIGN(ip, i, 0);
        error = bwrite(bp);
        if (error)
            allerror = error;
        if (ip->i_ump->um_fstype == UFS1)
            bap1 = (int32_t *)copy;
        else
            bap2 = (int64_t *)copy;
    }

    /*
     * Recursively free totally unused blocks.
     */
    for (i = FFS_NINDIR(fs) - 1, nlbn = lbn + 1 - i * factor; i > last;
            i--, nlbn += factor) {
        nb = RBAP(ip, i);
        if (nb == 0)
            continue;
        if (level > SINGLE) {
            error = ffs_indirtrunc(ip, nlbn, FFS_FSBTODB(fs, nb),
                                   (daddr_t)-1, level - 1,
                                   &blkcount);
            if (error)
                allerror = error;
            blocksreleased += blkcount;
        }
        if ((ip->i_ump->um_mountp->mnt_wapbl) &&
                ((level > SINGLE) || (ITOV(ip)->v_type != VREG))) {
            UFS_WAPBL_REGISTER_DEALLOCATION(ip->i_ump->um_mountp,
                                            FFS_FSBTODB(fs, nb), fs->fs_bsize);
        } else
            ffs_blkfree(fs, ip->i_devvp, nb, fs->fs_bsize,
                        ip->i_number);
        blocksreleased += nblocks;
    }

    /*
     * Recursively free last partial block.
     */
    if (level > SINGLE && lastbn >= 0) {
        last = lastbn % factor;
        nb = RBAP(ip, i);
        if (nb != 0) {
            error = ffs_indirtrunc(ip, nlbn, FFS_FSBTODB(fs, nb),
                                   last, level - 1, &blkcount);
            if (error)
                allerror = error;
            blocksreleased += blkcount;
        }
    }

    if (copy != NULL) {
        kmem_free(copy, fs->fs_bsize);
    } else {
        brelse(bp, BC_INVAL);
    }

    *countp = blocksreleased;
    return (allerror);
}
示例#6
0
/*
 * Truncate the inode oip to at most length size, freeing the
 * disk blocks.
 */
int
ffs_truncate(struct vnode *ovp, off_t length, int ioflag, kauth_cred_t cred)
{
    daddr_t lastblock;
    struct inode *oip = VTOI(ovp);
    daddr_t bn, lastiblock[UFS_NIADDR], indir_lbn[UFS_NIADDR];
    daddr_t blks[UFS_NDADDR + UFS_NIADDR];
    struct fs *fs;
    int offset, pgoffset, level;
    int64_t count, blocksreleased = 0;
    int i, aflag, nblocks;
    int error, allerror = 0;
    off_t osize;
    int sync;
    struct ufsmount *ump = oip->i_ump;

    if (ovp->v_type == VCHR || ovp->v_type == VBLK ||
            ovp->v_type == VFIFO || ovp->v_type == VSOCK) {
        KASSERT(oip->i_size == 0);
        return 0;
    }

    if (length < 0)
        return (EINVAL);

    if (ovp->v_type == VLNK &&
            (oip->i_size < ump->um_maxsymlinklen ||
             (ump->um_maxsymlinklen == 0 && DIP(oip, blocks) == 0))) {
        KDASSERT(length == 0);
        memset(SHORTLINK(oip), 0, (size_t)oip->i_size);
        oip->i_size = 0;
        DIP_ASSIGN(oip, size, 0);
        oip->i_flag |= IN_CHANGE | IN_UPDATE;
        return (ffs_update(ovp, NULL, NULL, 0));
    }
    if (oip->i_size == length) {
        /* still do a uvm_vnp_setsize() as writesize may be larger */
        uvm_vnp_setsize(ovp, length);
        oip->i_flag |= IN_CHANGE | IN_UPDATE;
        return (ffs_update(ovp, NULL, NULL, 0));
    }
    fs = oip->i_fs;
    if (length > ump->um_maxfilesize)
        return (EFBIG);

    if ((oip->i_flags & SF_SNAPSHOT) != 0)
        ffs_snapremove(ovp);

    osize = oip->i_size;
    aflag = ioflag & IO_SYNC ? B_SYNC : 0;

    /*
     * Lengthen the size of the file. We must ensure that the
     * last byte of the file is allocated. Since the smallest
     * value of osize is 0, length will be at least 1.
     */

    if (osize < length) {
        if (ffs_lblkno(fs, osize) < UFS_NDADDR &&
                ffs_lblkno(fs, osize) != ffs_lblkno(fs, length) &&
                ffs_blkroundup(fs, osize) != osize) {
            off_t eob;

            eob = ffs_blkroundup(fs, osize);
            uvm_vnp_setwritesize(ovp, eob);
            error = ufs_balloc_range(ovp, osize, eob - osize,
                                     cred, aflag);
            if (error) {
                (void) ffs_truncate(ovp, osize,
                                    ioflag & IO_SYNC, cred);
                return error;
            }
            if (ioflag & IO_SYNC) {
                mutex_enter(ovp->v_interlock);
                VOP_PUTPAGES(ovp,
                             trunc_page(osize & fs->fs_bmask),
                             round_page(eob), PGO_CLEANIT | PGO_SYNCIO |
                             PGO_JOURNALLOCKED);
            }
        }
        uvm_vnp_setwritesize(ovp, length);
        error = ufs_balloc_range(ovp, length - 1, 1, cred, aflag);
        if (error) {
            (void) ffs_truncate(ovp, osize, ioflag & IO_SYNC, cred);
            return (error);
        }
        uvm_vnp_setsize(ovp, length);
        oip->i_flag |= IN_CHANGE | IN_UPDATE;
        KASSERT(ovp->v_size == oip->i_size);
        return (ffs_update(ovp, NULL, NULL, 0));
    }

    /*
     * When truncating a regular file down to a non-block-aligned size,
     * we must zero the part of last block which is past the new EOF.
     * We must synchronously flush the zeroed pages to disk
     * since the new pages will be invalidated as soon as we
     * inform the VM system of the new, smaller size.
     * We must do this before acquiring the GLOCK, since fetching
     * the pages will acquire the GLOCK internally.
     * So there is a window where another thread could see a whole
     * zeroed page past EOF, but that's life.
     */

    offset = ffs_blkoff(fs, length);
    pgoffset = length & PAGE_MASK;
    if (ovp->v_type == VREG && (pgoffset != 0 || offset != 0) &&
            osize > length) {
        daddr_t lbn;
        voff_t eoz;
        int size;

        if (offset != 0) {
            error = ufs_balloc_range(ovp, length - 1, 1, cred,
                                     aflag);
            if (error)
                return error;
        }
        lbn = ffs_lblkno(fs, length);
        size = ffs_blksize(fs, oip, lbn);
        eoz = MIN(MAX(ffs_lblktosize(fs, lbn) + size, round_page(pgoffset)),
                  osize);
        ubc_zerorange(&ovp->v_uobj, length, eoz - length,
                      UBC_UNMAP_FLAG(ovp));
        if (round_page(eoz) > round_page(length)) {
            mutex_enter(ovp->v_interlock);
            error = VOP_PUTPAGES(ovp, round_page(length),
                                 round_page(eoz),
                                 PGO_CLEANIT | PGO_DEACTIVATE | PGO_JOURNALLOCKED |
                                 ((ioflag & IO_SYNC) ? PGO_SYNCIO : 0));
            if (error)
                return error;
        }
    }

    genfs_node_wrlock(ovp);
    oip->i_size = length;
    DIP_ASSIGN(oip, size, length);
    uvm_vnp_setsize(ovp, length);
    /*
     * Calculate index into inode's block list of
     * last direct and indirect blocks (if any)
     * which we want to keep.  Lastblock is -1 when
     * the file is truncated to 0.
     */
    lastblock = ffs_lblkno(fs, length + fs->fs_bsize - 1) - 1;
    lastiblock[SINGLE] = lastblock - UFS_NDADDR;
    lastiblock[DOUBLE] = lastiblock[SINGLE] - FFS_NINDIR(fs);
    lastiblock[TRIPLE] = lastiblock[DOUBLE] - FFS_NINDIR(fs) * FFS_NINDIR(fs);
    nblocks = btodb(fs->fs_bsize);
    /*
     * Update file and block pointers on disk before we start freeing
     * blocks.  If we crash before free'ing blocks below, the blocks
     * will be returned to the free list.  lastiblock values are also
     * normalized to -1 for calls to ffs_indirtrunc below.
     */
    sync = 0;
    for (level = TRIPLE; level >= SINGLE; level--) {
        blks[UFS_NDADDR + level] = DIP(oip, ib[level]);
        if (lastiblock[level] < 0 && blks[UFS_NDADDR + level] != 0) {
            sync = 1;
            DIP_ASSIGN(oip, ib[level], 0);
            lastiblock[level] = -1;
        }
    }
    for (i = 0; i < UFS_NDADDR; i++) {
        blks[i] = DIP(oip, db[i]);
        if (i > lastblock && blks[i] != 0) {
            sync = 1;
            DIP_ASSIGN(oip, db[i], 0);
        }
    }
    oip->i_flag |= IN_CHANGE | IN_UPDATE;
    if (sync) {
        error = ffs_update(ovp, NULL, NULL, UPDATE_WAIT);
        if (error && !allerror)
            allerror = error;
    }

    /*
     * Having written the new inode to disk, save its new configuration
     * and put back the old block pointers long enough to process them.
     * Note that we save the new block configuration so we can check it
     * when we are done.
     */
    for (i = 0; i < UFS_NDADDR; i++) {
        bn = DIP(oip, db[i]);
        DIP_ASSIGN(oip, db[i], blks[i]);
        blks[i] = bn;
    }
    for (i = 0; i < UFS_NIADDR; i++) {
        bn = DIP(oip, ib[i]);
        DIP_ASSIGN(oip, ib[i], blks[UFS_NDADDR + i]);
        blks[UFS_NDADDR + i] = bn;
    }

    oip->i_size = osize;
    DIP_ASSIGN(oip, size, osize);
    error = vtruncbuf(ovp, lastblock + 1, 0, 0);
    if (error && !allerror)
        allerror = error;

    /*
     * Indirect blocks first.
     */
    indir_lbn[SINGLE] = -UFS_NDADDR;
    indir_lbn[DOUBLE] = indir_lbn[SINGLE] - FFS_NINDIR(fs) - 1;
    indir_lbn[TRIPLE] = indir_lbn[DOUBLE] - FFS_NINDIR(fs) * FFS_NINDIR(fs) - 1;
    for (level = TRIPLE; level >= SINGLE; level--) {
        if (oip->i_ump->um_fstype == UFS1)
            bn = ufs_rw32(oip->i_ffs1_ib[level],UFS_FSNEEDSWAP(fs));
        else
            bn = ufs_rw64(oip->i_ffs2_ib[level],UFS_FSNEEDSWAP(fs));
        if (bn != 0) {
            error = ffs_indirtrunc(oip, indir_lbn[level],
                                   FFS_FSBTODB(fs, bn), lastiblock[level], level, &count);
            if (error)
                allerror = error;
            blocksreleased += count;
            if (lastiblock[level] < 0) {
                DIP_ASSIGN(oip, ib[level], 0);
                if (oip->i_ump->um_mountp->mnt_wapbl) {
                    UFS_WAPBL_REGISTER_DEALLOCATION(
                        oip->i_ump->um_mountp,
                        FFS_FSBTODB(fs, bn), fs->fs_bsize);
                } else
                    ffs_blkfree(fs, oip->i_devvp, bn,
                                fs->fs_bsize, oip->i_number);
                blocksreleased += nblocks;
            }
        }
        if (lastiblock[level] >= 0)
            goto done;
    }

    /*
     * All whole direct blocks or frags.
     */
    for (i = UFS_NDADDR - 1; i > lastblock; i--) {
        long bsize;

        if (oip->i_ump->um_fstype == UFS1)
            bn = ufs_rw32(oip->i_ffs1_db[i], UFS_FSNEEDSWAP(fs));
        else
            bn = ufs_rw64(oip->i_ffs2_db[i], UFS_FSNEEDSWAP(fs));
        if (bn == 0)
            continue;
        DIP_ASSIGN(oip, db[i], 0);
        bsize = ffs_blksize(fs, oip, i);
        if ((oip->i_ump->um_mountp->mnt_wapbl) &&
                (ovp->v_type != VREG)) {
            UFS_WAPBL_REGISTER_DEALLOCATION(oip->i_ump->um_mountp,
                                            FFS_FSBTODB(fs, bn), bsize);
        } else
            ffs_blkfree(fs, oip->i_devvp, bn, bsize, oip->i_number);
        blocksreleased += btodb(bsize);
    }
    if (lastblock < 0)
        goto done;

    /*
     * Finally, look for a change in size of the
     * last direct block; release any frags.
     */
    if (oip->i_ump->um_fstype == UFS1)
        bn = ufs_rw32(oip->i_ffs1_db[lastblock], UFS_FSNEEDSWAP(fs));
    else
        bn = ufs_rw64(oip->i_ffs2_db[lastblock], UFS_FSNEEDSWAP(fs));
    if (bn != 0) {
        long oldspace, newspace;

        /*
         * Calculate amount of space we're giving
         * back as old block size minus new block size.
         */
        oldspace = ffs_blksize(fs, oip, lastblock);
        oip->i_size = length;
        DIP_ASSIGN(oip, size, length);
        newspace = ffs_blksize(fs, oip, lastblock);
        if (newspace == 0)
            panic("itrunc: newspace");
        if (oldspace - newspace > 0) {
            /*
             * Block number of space to be free'd is
             * the old block # plus the number of frags
             * required for the storage we're keeping.
             */
            bn += ffs_numfrags(fs, newspace);
            if ((oip->i_ump->um_mountp->mnt_wapbl) &&
                    (ovp->v_type != VREG)) {
                UFS_WAPBL_REGISTER_DEALLOCATION(
                    oip->i_ump->um_mountp, FFS_FSBTODB(fs, bn),
                    oldspace - newspace);
            } else
                ffs_blkfree(fs, oip->i_devvp, bn,
                            oldspace - newspace, oip->i_number);
            blocksreleased += btodb(oldspace - newspace);
        }
    }

done:
#ifdef DIAGNOSTIC
    for (level = SINGLE; level <= TRIPLE; level++)
        if (blks[UFS_NDADDR + level] != DIP(oip, ib[level]))
            panic("itrunc1");
    for (i = 0; i < UFS_NDADDR; i++)
        if (blks[i] != DIP(oip, db[i]))
            panic("itrunc2");
    if (length == 0 &&
            (!LIST_EMPTY(&ovp->v_cleanblkhd) || !LIST_EMPTY(&ovp->v_dirtyblkhd)))
        panic("itrunc3");
#endif /* DIAGNOSTIC */
    /*
     * Put back the real size.
     */
    oip->i_size = length;
    DIP_ASSIGN(oip, size, length);
    DIP_ADD(oip, blocks, -blocksreleased);
    genfs_node_unlock(ovp);
    oip->i_flag |= IN_CHANGE;
    UFS_WAPBL_UPDATE(ovp, NULL, NULL, 0);
#if defined(QUOTA) || defined(QUOTA2)
    (void) chkdq(oip, -blocksreleased, NOCRED, 0);
#endif
    KASSERT(ovp->v_type != VREG || ovp->v_size == oip->i_size);
    return (allerror);
}
示例#7
0
/*
 * Truncate the inode ip to at most length size, freeing the
 * disk blocks.
 */
int
ffs_truncate(vnode *vp, off_t length, int flags, Ucred *cred)
{
	print("HARVEY TODO: %s\n", __func__);
#if 0
	struct inode *ip;
	ufs2_daddr_t bn, lbn, lastblock, lastiblock[UFS_NIADDR];
	ufs2_daddr_t indir_lbn[UFS_NIADDR], oldblks[UFS_NDADDR + UFS_NIADDR];
	ufs2_daddr_t newblks[UFS_NDADDR + UFS_NIADDR];
	ufs2_daddr_t count, blocksreleased = 0, datablocks, blkno;
	struct bufobj *bo;
	struct fs *fs;
	struct buf *bp;
	struct ufsmount *ump;
	int softdeptrunc, journaltrunc;
	int needextclean, extblocks;
	int offset, size, level, nblocks;
	int i, error, allerror, indiroff, waitforupdate;
	off_t osize;

	ip = VTOI(vp);
	ump = VFSTOUFS(vp->v_mount);
	fs = ump->um_fs;
	bo = &vp->v_bufobj;

	ASSERT_VOP_LOCKED(vp, "ffs_truncate");

	if (length < 0)
		return (EINVAL);
	if (length > fs->fs_maxfilesize)
		return (EFBIG);
#ifdef QUOTA
	error = getinoquota(ip);
	if (error)
		return (error);
#endif
	/*
	 * Historically clients did not have to specify which data
	 * they were truncating. So, if not specified, we assume
	 * traditional behavior, e.g., just the normal data.
	 */
	if ((flags & (IO_EXT | IO_NORMAL)) == 0)
		flags |= IO_NORMAL;
	if (!DOINGSOFTDEP(vp) && !DOINGASYNC(vp))
		flags |= IO_SYNC;
	waitforupdate = (flags & IO_SYNC) != 0 || !DOINGASYNC(vp);
	/*
	 * If we are truncating the extended-attributes, and cannot
	 * do it with soft updates, then do it slowly here. If we are
	 * truncating both the extended attributes and the file contents
	 * (e.g., the file is being unlinked), then pick it off with
	 * soft updates below.
	 */
	allerror = 0;
	needextclean = 0;
	softdeptrunc = 0;
	journaltrunc = DOINGSUJ(vp);
	if (journaltrunc == 0 && DOINGSOFTDEP(vp) && length == 0)
		softdeptrunc = !softdep_slowdown(vp);
	extblocks = 0;
	datablocks = DIP(ip, i_blocks);
	if (fs->fs_magic == FS_UFS2_MAGIC && ip->i_din2->di_extsize > 0) {
		extblocks = btodb(fragroundup(fs, ip->i_din2->di_extsize));
		datablocks -= extblocks;
	}
	if ((flags & IO_EXT) && extblocks > 0) {
		if (length != 0)
			panic("ffs_truncate: partial trunc of extdata");
		if (softdeptrunc || journaltrunc) {
			if ((flags & IO_NORMAL) == 0)
				goto extclean;
			needextclean = 1;
		} else {
			if ((error = ffs_syncvnode(vp, MNT_WAIT, 0)) != 0)
				return (error);
#ifdef QUOTA
			(void) chkdq(ip, -extblocks, NOCRED, 0);
#endif
			vinvalbuf(vp, V_ALT, 0, 0);
			vn_pages_remove(vp,
			    OFF_TO_IDX(lblktosize(fs, -extblocks)), 0);
			osize = ip->i_din2->di_extsize;
			ip->i_din2->di_blocks -= extblocks;
			ip->i_din2->di_extsize = 0;
			for (i = 0; i < UFS_NXADDR; i++) {
				oldblks[i] = ip->i_din2->di_extb[i];
				ip->i_din2->di_extb[i] = 0;
			}
			ip->i_flag |= IN_CHANGE;
			if ((error = ffs_update(vp, waitforupdate)))
				return (error);
			for (i = 0; i < UFS_NXADDR; i++) {
				if (oldblks[i] == 0)
					continue;
				ffs_blkfree(ump, fs, ITODEVVP(ip), oldblks[i],
				    sblksize(fs, osize, i), ip->i_number,
				    vp->v_type, nil);
			}
		}
	}
	if ((flags & IO_NORMAL) == 0)
		return (0);
	if (vp->v_type == VLNK &&
	    (ip->i_size < vp->v_mount->mnt_maxsymlinklen ||
	     datablocks == 0)) {
#ifdef INVARIANTS
		if (length != 0)
			panic("ffs_truncate: partial truncate of symlink");
#endif
		bzero(SHORTLINK(ip), (uint)ip->i_size);
		ip->i_size = 0;
		DIP_SET(ip, i_size, 0);
		ip->i_flag |= IN_CHANGE | IN_UPDATE;
		if (needextclean)
			goto extclean;
		return (ffs_update(vp, waitforupdate));
	}
	if (ip->i_size == length) {
		ip->i_flag |= IN_CHANGE | IN_UPDATE;
		if (needextclean)
			goto extclean;
		return (ffs_update(vp, 0));
	}
	if (fs->fs_ronly)
		panic("ffs_truncate: read-only filesystem");
	if (IS_SNAPSHOT(ip))
		ffs_snapremove(vp);
	vp->v_lasta = vp->v_clen = vp->v_cstart = vp->v_lastw = 0;
	osize = ip->i_size;
	/*
	 * Lengthen the size of the file. We must ensure that the
	 * last byte of the file is allocated. Since the smallest
	 * value of osize is 0, length will be at least 1.
	 */
	if (osize < length) {
		vnode_pager_setsize(vp, length);
		flags |= BA_CLRBUF;
		error = UFS_BALLOC(vp, length - 1, 1, cred, flags, &bp);
		if (error) {
			vnode_pager_setsize(vp, osize);
			return (error);
		}
		ip->i_size = length;
		DIP_SET(ip, i_size, length);
		if (bp->b_bufsize == fs->fs_bsize)
			bp->b_flags |= B_CLUSTEROK;
		if (flags & IO_SYNC)
			bwrite(bp);
		else if (DOINGASYNC(vp))
			bdwrite(bp);
		else
			bawrite(bp);
		ip->i_flag |= IN_CHANGE | IN_UPDATE;
		return (ffs_update(vp, waitforupdate));
	}
	/*
	 * Lookup block number for a given offset. Zero length files
	 * have no blocks, so return a blkno of -1.
	 */
	lbn = lblkno(fs, length - 1);
	if (length == 0) {
		blkno = -1;
	} else if (lbn < UFS_NDADDR) {
		blkno = DIP(ip, i_db[lbn]);
	} else {
		error = UFS_BALLOC(vp, lblktosize(fs, (off_t)lbn), fs->fs_bsize,
		    cred, BA_METAONLY, &bp);
		if (error)
			return (error);
		indiroff = (lbn - UFS_NDADDR) % NINDIR(fs);
		if (I_IS_UFS1(ip))
			blkno = ((ufs1_daddr_t *)(bp->b_data))[indiroff];
		else
			blkno = ((ufs2_daddr_t *)(bp->b_data))[indiroff];
		/*
		 * If the block number is non-zero, then the indirect block
		 * must have been previously allocated and need not be written.
		 * If the block number is zero, then we may have allocated
		 * the indirect block and hence need to write it out.
		 */
		if (blkno != 0)
			brelse(bp);
		else if (flags & IO_SYNC)
			bwrite(bp);
		else
			bdwrite(bp);
	}
	/*
	 * If the block number at the new end of the file is zero,
	 * then we must allocate it to ensure that the last block of 
	 * the file is allocated. Soft updates does not handle this
	 * case, so here we have to clean up the soft updates data
	 * structures describing the allocation past the truncation
	 * point. Finding and deallocating those structures is a lot of
	 * work. Since partial truncation with a hole at the end occurs
	 * rarely, we solve the problem by syncing the file so that it
	 * will have no soft updates data structures left.
	 */
	if (blkno == 0 && (error = ffs_syncvnode(vp, MNT_WAIT, 0)) != 0)
		return (error);
	if (blkno != 0 && DOINGSOFTDEP(vp)) {
		if (softdeptrunc == 0 && journaltrunc == 0) {
			/*
			 * If soft updates cannot handle this truncation,
			 * clean up soft dependency data structures and
			 * fall through to the synchronous truncation.
			 */
			if ((error = ffs_syncvnode(vp, MNT_WAIT, 0)) != 0)
				return (error);
		} else {
			flags = IO_NORMAL | (needextclean ? IO_EXT: 0);
			if (journaltrunc)
				softdep_journal_freeblocks(ip, cred, length,
				    flags);
			else
				softdep_setup_freeblocks(ip, length, flags);
			ASSERT_VOP_LOCKED(vp, "ffs_truncate1");
			if (journaltrunc == 0) {
				ip->i_flag |= IN_CHANGE | IN_UPDATE;
				error = ffs_update(vp, 0);
			}
			return (error);
		}
	}
	/*
	 * Shorten the size of the file. If the last block of the
	 * shortened file is unallocated, we must allocate it.
	 * Additionally, if the file is not being truncated to a
	 * block boundary, the contents of the partial block
	 * following the end of the file must be zero'ed in
	 * case it ever becomes accessible again because of
	 * subsequent file growth. Directories however are not
	 * zero'ed as they should grow back initialized to empty.
	 */
	offset = blkoff(fs, length);
	if (blkno != 0 && offset == 0) {
		ip->i_size = length;
		DIP_SET(ip, i_size, length);
	} else {
		lbn = lblkno(fs, length);
		flags |= BA_CLRBUF;
		error = UFS_BALLOC(vp, length - 1, 1, cred, flags, &bp);
		if (error)
			return (error);
		/*
		 * When we are doing soft updates and the UFS_BALLOC
		 * above fills in a direct block hole with a full sized
		 * block that will be truncated down to a fragment below,
		 * we must flush out the block dependency with an FSYNC
		 * so that we do not get a soft updates inconsistency
		 * when we create the fragment below.
		 */
		if (DOINGSOFTDEP(vp) && lbn < UFS_NDADDR &&
		    fragroundup(fs, blkoff(fs, length)) < fs->fs_bsize &&
		    (error = ffs_syncvnode(vp, MNT_WAIT, 0)) != 0)
			return (error);
		ip->i_size = length;
		DIP_SET(ip, i_size, length);
		size = blksize(fs, ip, lbn);
		if (vp->v_type != VDIR && offset != 0)
			bzero((char *)bp->b_data + offset,
			    (uint)(size - offset));
		/* Kirk's code has reallocbuf(bp, size, 1) here */
		allocbuf(bp, size);
		if (bp->b_bufsize == fs->fs_bsize)
			bp->b_flags |= B_CLUSTEROK;
		if (flags & IO_SYNC)
			bwrite(bp);
		else if (DOINGASYNC(vp))
			bdwrite(bp);
		else
			bawrite(bp);
	}
	/*
	 * Calculate index into inode's block list of
	 * last direct and indirect blocks (if any)
	 * which we want to keep.  Lastblock is -1 when
	 * the file is truncated to 0.
	 */
	lastblock = lblkno(fs, length + fs->fs_bsize - 1) - 1;
	lastiblock[SINGLE] = lastblock - UFS_NDADDR;
	lastiblock[DOUBLE] = lastiblock[SINGLE] - NINDIR(fs);
	lastiblock[TRIPLE] = lastiblock[DOUBLE] - NINDIR(fs) * NINDIR(fs);
	nblocks = btodb(fs->fs_bsize);
	/*
	 * Update file and block pointers on disk before we start freeing
	 * blocks.  If we crash before free'ing blocks below, the blocks
	 * will be returned to the free list.  lastiblock values are also
	 * normalized to -1 for calls to ffs_indirtrunc below.
	 */
	for (level = TRIPLE; level >= SINGLE; level--) {
		oldblks[UFS_NDADDR + level] = DIP(ip, i_ib[level]);
		if (lastiblock[level] < 0) {
			DIP_SET(ip, i_ib[level], 0);
			lastiblock[level] = -1;
		}
	}
	for (i = 0; i < UFS_NDADDR; i++) {
		oldblks[i] = DIP(ip, i_db[i]);
		if (i > lastblock)
			DIP_SET(ip, i_db[i], 0);
	}
	ip->i_flag |= IN_CHANGE | IN_UPDATE;
	allerror = ffs_update(vp, waitforupdate);
	
	/*
	 * Having written the new inode to disk, save its new configuration
	 * and put back the old block pointers long enough to process them.
	 * Note that we save the new block configuration so we can check it
	 * when we are done.
	 */
	for (i = 0; i < UFS_NDADDR; i++) {
		newblks[i] = DIP(ip, i_db[i]);
		DIP_SET(ip, i_db[i], oldblks[i]);
	}
	for (i = 0; i < UFS_NIADDR; i++) {
		newblks[UFS_NDADDR + i] = DIP(ip, i_ib[i]);
		DIP_SET(ip, i_ib[i], oldblks[UFS_NDADDR + i]);
	}
	ip->i_size = osize;
	DIP_SET(ip, i_size, osize);

	error = vtruncbuf(vp, cred, length, fs->fs_bsize);
	if (error && (allerror == 0))
		allerror = error;

	/*
	 * Indirect blocks first.
	 */
	indir_lbn[SINGLE] = -UFS_NDADDR;
	indir_lbn[DOUBLE] = indir_lbn[SINGLE] - NINDIR(fs) - 1;
	indir_lbn[TRIPLE] = indir_lbn[DOUBLE] - NINDIR(fs) * NINDIR(fs) - 1;
	for (level = TRIPLE; level >= SINGLE; level--) {
		bn = DIP(ip, i_ib[level]);
		if (bn != 0) {
			error = ffs_indirtrunc(ip, indir_lbn[level],
			    fsbtodb(fs, bn), lastiblock[level], level, &count);
			if (error)
				allerror = error;
			blocksreleased += count;
			if (lastiblock[level] < 0) {
				DIP_SET(ip, i_ib[level], 0);
				ffs_blkfree(ump, fs, ump->um_devvp, bn,
				    fs->fs_bsize, ip->i_number,
				    vp->v_type, nil);
				blocksreleased += nblocks;
			}
		}
		if (lastiblock[level] >= 0)
			goto done;
	}

	/*
	 * All whole direct blocks or frags.
	 */
	for (i = UFS_NDADDR - 1; i > lastblock; i--) {
		long bsize;

		bn = DIP(ip, i_db[i]);
		if (bn == 0)
			continue;
		DIP_SET(ip, i_db[i], 0);
		bsize = blksize(fs, ip, i);
		ffs_blkfree(ump, fs, ump->um_devvp, bn, bsize, ip->i_number,
		    vp->v_type, nil);
		blocksreleased += btodb(bsize);
	}
	if (lastblock < 0)
		goto done;

	/*
	 * Finally, look for a change in size of the
	 * last direct block; release any frags.
	 */
	bn = DIP(ip, i_db[lastblock]);
	if (bn != 0) {
		long oldspace, newspace;

		/*
		 * Calculate amount of space we're giving
		 * back as old block size minus new block size.
		 */
		oldspace = blksize(fs, ip, lastblock);
		ip->i_size = length;
		DIP_SET(ip, i_size, length);
		newspace = blksize(fs, ip, lastblock);
		if (newspace == 0)
			panic("ffs_truncate: newspace");
		if (oldspace - newspace > 0) {
			/*
			 * Block number of space to be free'd is
			 * the old block # plus the number of frags
			 * required for the storage we're keeping.
			 */
			bn += numfrags(fs, newspace);
			ffs_blkfree(ump, fs, ump->um_devvp, bn,
			   oldspace - newspace, ip->i_number, vp->v_type, nil);
			blocksreleased += btodb(oldspace - newspace);
		}
	}
done:
#ifdef INVARIANTS
	for (level = SINGLE; level <= TRIPLE; level++)
		if (newblks[UFS_NDADDR + level] != DIP(ip, i_ib[level]))
			panic("ffs_truncate1");
	for (i = 0; i < UFS_NDADDR; i++)
		if (newblks[i] != DIP(ip, i_db[i]))
			panic("ffs_truncate2");
	BO_LOCK(bo);
	if (length == 0 &&
	    (fs->fs_magic != FS_UFS2_MAGIC || ip->i_din2->di_extsize == 0) &&
	    (bo->bo_dirty.bv_cnt > 0 || bo->bo_clean.bv_cnt > 0))
		panic("ffs_truncate3");
	BO_UNLOCK(bo);
#endif /* INVARIANTS */
	/*
	 * Put back the real size.
	 */
	ip->i_size = length;
	DIP_SET(ip, i_size, length);
	if (DIP(ip, i_blocks) >= blocksreleased)
		DIP_SET(ip, i_blocks, DIP(ip, i_blocks) - blocksreleased);
	else	/* sanity */
		DIP_SET(ip, i_blocks, 0);
	ip->i_flag |= IN_CHANGE;
#ifdef QUOTA
	(void) chkdq(ip, -blocksreleased, NOCRED, 0);
#endif
	return (allerror);

extclean:
	if (journaltrunc)
		softdep_journal_freeblocks(ip, cred, length, IO_EXT);
	else
		softdep_setup_freeblocks(ip, length, IO_EXT);
	return (ffs_update(vp, waitforupdate));

#endif // 0
	return 0;
}