示例#1
0
/*
 * Balloc defines the structure of file system storage
 * by allocating the physical blocks on a device given
 * the inode and the logical block number in a file.
 */
int
ext2fs_balloc(struct inode *ip, daddr_t bn, int size,
    kauth_cred_t cred, struct buf **bpp, int flags)
{
	struct m_ext2fs *fs;
	daddr_t nb;
	struct buf *bp, *nbp;
	struct vnode *vp = ITOV(ip);
	struct indir indirs[EXT2FS_NIADDR + 2];
	daddr_t newb, lbn, pref;
	int32_t *bap;	/* XXX ondisk32 */
	int num, i, error;
	u_int deallocated;
	daddr_t *blkp, *allocblk, allociblk[EXT2FS_NIADDR + 1];
	int32_t *allocib;	/* XXX ondisk32 */
	int unwindidx = -1;
	UVMHIST_FUNC("ext2fs_balloc"); UVMHIST_CALLED(ubchist);

	UVMHIST_LOG(ubchist, "bn 0x%x", bn,0,0,0);

	if (bpp != NULL) {
		*bpp = NULL;
	}
	if (bn < 0)
		return (EFBIG);
	fs = ip->i_e2fs;
	lbn = bn;

	/*
	 * The first EXT2FS_NDADDR blocks are direct blocks
	 */
	if (bn < EXT2FS_NDADDR) {
		/* XXX ondisk32 */
		nb = fs2h32(ip->i_e2fs_blocks[bn]);
		if (nb != 0) {

			/*
			 * the block is already allocated, just read it.
			 */

			if (bpp != NULL) {
				error = bread(vp, bn, fs->e2fs_bsize, NOCRED,
					      B_MODIFY, &bp);
				if (error) {
					return (error);
				}
				*bpp = bp;
			}
			return (0);
		}

		/*
		 * allocate a new direct block.
		 */

		error = ext2fs_alloc(ip, bn,
		    ext2fs_blkpref(ip, bn, bn, &ip->i_e2fs_blocks[0]),
		    cred, &newb);
		if (error)
			return (error);
		ip->i_e2fs_last_lblk = lbn;
		ip->i_e2fs_last_blk = newb;
		/* XXX ondisk32 */
		ip->i_e2fs_blocks[bn] = h2fs32((int32_t)newb);
		ip->i_flag |= IN_CHANGE | IN_UPDATE;
		if (bpp != NULL) {
			bp = getblk(vp, bn, fs->e2fs_bsize, 0, 0);
			bp->b_blkno = EXT2_FSBTODB(fs, newb);
			if (flags & B_CLRBUF)
				clrbuf(bp);
			*bpp = bp;
		}
		return (0);
	}
	/*
	 * Determine the number of levels of indirection.
	 */
	pref = 0;
	if ((error = ufs_getlbns(vp, bn, indirs, &num)) != 0)
		return(error);
#ifdef DIAGNOSTIC
	if (num < 1)
		panic ("ext2fs_balloc: ufs_getlbns returned indirect block\n");
#endif
	/*
	 * Fetch the first indirect block allocating if necessary.
	 */
	--num;
	/* XXX ondisk32 */
	nb = fs2h32(ip->i_e2fs_blocks[EXT2FS_NDADDR + indirs[0].in_off]);
	allocib = NULL;
	allocblk = allociblk;
	if (nb == 0) {
		pref = ext2fs_blkpref(ip, lbn, 0, (int32_t *)0);
		error = ext2fs_alloc(ip, lbn, pref, cred, &newb);
		if (error)
			return (error);
		nb = newb;
		*allocblk++ = nb;
		ip->i_e2fs_last_blk = newb;
		bp = getblk(vp, indirs[1].in_lbn, fs->e2fs_bsize, 0, 0);
		bp->b_blkno = EXT2_FSBTODB(fs, newb);
		clrbuf(bp);
		/*
		 * Write synchronously so that indirect blocks
		 * never point at garbage.
		 */
		if ((error = bwrite(bp)) != 0)
			goto fail;
		unwindidx = 0;
		allocib = &ip->i_e2fs_blocks[EXT2FS_NDADDR + indirs[0].in_off];
		/* XXX ondisk32 */
		*allocib = h2fs32((int32_t)newb);
		ip->i_flag |= IN_CHANGE | IN_UPDATE;
	}
	/*
	 * Fetch through the indirect blocks, allocating as necessary.
	 */
	for (i = 1;;) {
		error = bread(vp,
		    indirs[i].in_lbn, (int)fs->e2fs_bsize, NOCRED, 0, &bp);
		if (error) {
			goto fail;
		}
		bap = (int32_t *)bp->b_data;	/* XXX ondisk32 */
		nb = fs2h32(bap[indirs[i].in_off]);
		if (i == num)
			break;
		i++;
		if (nb != 0) {
			brelse(bp, 0);
			continue;
		}
		pref = ext2fs_blkpref(ip, lbn, 0, (int32_t *)0);
		error = ext2fs_alloc(ip, lbn, pref, cred, &newb);
		if (error) {
			brelse(bp, 0);
			goto fail;
		}
		nb = newb;
		*allocblk++ = nb;
		ip->i_e2fs_last_blk = newb;
		nbp = getblk(vp, indirs[i].in_lbn, fs->e2fs_bsize, 0, 0);
		nbp->b_blkno = EXT2_FSBTODB(fs, nb);
		clrbuf(nbp);
		/*
		 * Write synchronously so that indirect blocks
		 * never point at garbage.
		 */
		if ((error = bwrite(nbp)) != 0) {
			brelse(bp, 0);
			goto fail;
		}
		if (unwindidx < 0)
			unwindidx = i - 1;
		/* XXX ondisk32 */
		bap[indirs[i - 1].in_off] = h2fs32((int32_t)nb);
		/*
		 * If required, write synchronously, otherwise use
		 * delayed write.
		 */
		if (flags & B_SYNC) {
			bwrite(bp);
		} else {
			bdwrite(bp);
		}
	}
	/*
	 * Get the data block, allocating if necessary.
	 */
	if (nb == 0) {
		pref = ext2fs_blkpref(ip, lbn, indirs[num].in_off, &bap[0]);
		error = ext2fs_alloc(ip, lbn, pref, cred, &newb);
		if (error) {
			brelse(bp, 0);
			goto fail;
		}
		nb = newb;
		*allocblk++ = nb;
		ip->i_e2fs_last_lblk = lbn;
		ip->i_e2fs_last_blk = newb;
		/* XXX ondisk32 */
		bap[indirs[num].in_off] = h2fs32((int32_t)nb);
		/*
		 * If required, write synchronously, otherwise use
		 * delayed write.
		 */
		if (flags & B_SYNC) {
			bwrite(bp);
		} else {
			bdwrite(bp);
		}
		if (bpp != NULL) {
			nbp = getblk(vp, lbn, fs->e2fs_bsize, 0, 0);
			nbp->b_blkno = EXT2_FSBTODB(fs, nb);
			if (flags & B_CLRBUF)
				clrbuf(nbp);
			*bpp = nbp;
		}
		return (0);
	}
	brelse(bp, 0);
	if (bpp != NULL) {
		if (flags & B_CLRBUF) {
			error = bread(vp, lbn, (int)fs->e2fs_bsize, NOCRED,
				      B_MODIFY, &nbp);
			if (error) {
				goto fail;
			}
		} else {
			nbp = getblk(vp, lbn, fs->e2fs_bsize, 0, 0);
			nbp->b_blkno = EXT2_FSBTODB(fs, nb);
		}
		*bpp = nbp;
	}
	return (0);
fail:
	/*
	 * If we have failed part way through block allocation, we
	 * have to deallocate any indirect blocks that we have allocated.
	 */
	for (deallocated = 0, blkp = allociblk; blkp < allocblk; blkp++) {
		ext2fs_blkfree(ip, *blkp);
		deallocated += fs->e2fs_bsize;
	}
	if (unwindidx >= 0) {
		if (unwindidx == 0) {
			*allocib = 0;
		} else {
			int r;

			r = bread(vp, indirs[unwindidx].in_lbn,
			    (int)fs->e2fs_bsize, NOCRED, B_MODIFY, &bp);
			if (r) {
				panic("Could not unwind indirect block, error %d", r);
			} else {
				bap = (int32_t *)bp->b_data; /* XXX ondisk32 */
				bap[indirs[unwindidx].in_off] = 0;
				if (flags & B_SYNC)
					bwrite(bp);
				else
					bdwrite(bp);
			}
		}
		for (i = unwindidx + 1; i <= num; i++) {
			bp = getblk(vp, indirs[i].in_lbn, (int)fs->e2fs_bsize,
			    0, 0);
			brelse(bp, BC_INVAL);
		}
	}
	if (deallocated) {
		ext2fs_setnblock(ip, ext2fs_nblock(ip) - btodb(deallocated));
		ip->i_e2fs_flags |= IN_CHANGE | IN_UPDATE;
	}
	return error;
}
示例#2
0
/*
 * Read an inode from disk and initialize this vnode / inode pair.
 * Caller assures no other thread will try to load this inode.
 */
int
ext2fs_loadvnode(struct mount *mp, struct vnode *vp,
    const void *key, size_t key_len, const void **new_key)
{
	ino_t ino;
	struct m_ext2fs *fs;
	struct inode *ip;
	struct ufsmount *ump;
	struct buf *bp;
	dev_t dev;
	int error;

	KASSERT(key_len == sizeof(ino));
	memcpy(&ino, key, key_len);
	ump = VFSTOUFS(mp);
	dev = ump->um_dev;
	fs = ump->um_e2fs;

	/* Read in the disk contents for the inode, copy into the inode. */
	error = bread(ump->um_devvp, EXT2_FSBTODB(fs, ino_to_fsba(fs, ino)),
	    (int)fs->e2fs_bsize, 0, &bp);
	if (error)
		return error;

	/* Allocate and initialize inode. */
	ip = pool_get(&ext2fs_inode_pool, PR_WAITOK);
	memset(ip, 0, sizeof(struct inode));
	vp->v_tag = VT_EXT2FS;
	vp->v_op = ext2fs_vnodeop_p;
	vp->v_vflag |= VV_LOCKSWORK;
	vp->v_data = ip;
	ip->i_vnode = vp;
	ip->i_ump = ump;
	ip->i_e2fs = fs;
	ip->i_dev = dev;
	ip->i_number = ino;
	ip->i_e2fs_last_lblk = 0;
	ip->i_e2fs_last_blk = 0;

	/* Initialize genfs node. */
	genfs_node_init(vp, &ext2fs_genfsops);

	error = ext2fs_loadvnode_content(fs, ino, bp, ip);
	brelse(bp, 0);
	if (error)
		return error;

	/* If the inode was deleted, reset all fields */
	if (ip->i_e2fs_dtime != 0) {
		ip->i_e2fs_mode = 0;
		(void)ext2fs_setsize(ip, 0);
		(void)ext2fs_setnblock(ip, 0);
		memset(ip->i_e2fs_blocks, 0, sizeof(ip->i_e2fs_blocks));
	}

	/* Initialize the vnode from the inode. */
	ext2fs_vinit(mp, ext2fs_specop_p, ext2fs_fifoop_p, &vp);

	/* Finish inode initialization. */
	ip->i_devvp = ump->um_devvp;
	vref(ip->i_devvp);

	/*
	 * Set up a generation number for this inode if it does not
	 * already have one. This should only happen on old filesystems.
	 */

	if (ip->i_e2fs_gen == 0) {
		if (++ext2gennumber < (u_long)time_second)
			ext2gennumber = time_second;
		ip->i_e2fs_gen = ext2gennumber;
		if ((mp->mnt_flag & MNT_RDONLY) == 0)
			ip->i_flag |= IN_MODIFIED;
	}
	uvm_vnp_setsize(vp, ext2fs_size(ip));
	*new_key = &ip->i_number;
	return 0;
}
示例#3
0
/*
 * Look up a EXT2FS dinode number to find its incore vnode, otherwise read it
 * in from disk.  If it is in core, wait for the lock bit to clear, then
 * return the inode locked.  Detection and handling of mount points must be
 * done by the calling routine.
 */
int
ext2fs_vget(struct mount *mp, ino_t ino, struct vnode **vpp)
{
	struct m_ext2fs *fs;
	struct inode *ip;
	struct ufsmount *ump;
	struct buf *bp;
	struct vnode *vp;
	dev_t dev;
	int error;
	void *cp;

	ump = VFSTOUFS(mp);
	dev = ump->um_dev;
retry:
	if ((*vpp = ufs_ihashget(dev, ino, LK_EXCLUSIVE)) != NULL)
		return (0);

	/* Allocate a new vnode/inode. */
	error = getnewvnode(VT_EXT2FS, mp, ext2fs_vnodeop_p, NULL, &vp);
	if (error) {
		*vpp = NULL;
		return (error);
	}
	ip = pool_get(&ext2fs_inode_pool, PR_WAITOK);

	mutex_enter(&ufs_hashlock);
	if ((*vpp = ufs_ihashget(dev, ino, 0)) != NULL) {
		mutex_exit(&ufs_hashlock);
		ungetnewvnode(vp);
		pool_put(&ext2fs_inode_pool, ip);
		goto retry;
	}

	vp->v_vflag |= VV_LOCKSWORK;

	memset(ip, 0, sizeof(struct inode));
	vp->v_data = ip;
	ip->i_vnode = vp;
	ip->i_ump = ump;
	ip->i_e2fs = fs = ump->um_e2fs;
	ip->i_dev = dev;
	ip->i_number = ino;
	ip->i_e2fs_last_lblk = 0;
	ip->i_e2fs_last_blk = 0;
	genfs_node_init(vp, &ext2fs_genfsops);

	/*
	 * Put it onto its hash chain and lock it so that other requests for
	 * this inode will block if they arrive while we are sleeping waiting
	 * for old data structures to be purged or for the contents of the
	 * disk portion of this inode to be read.
	 */

	ufs_ihashins(ip);
	mutex_exit(&ufs_hashlock);

	/* Read in the disk contents for the inode, copy into the inode. */
	error = bread(ump->um_devvp, EXT2_FSBTODB(fs, ino_to_fsba(fs, ino)),
	    (int)fs->e2fs_bsize, NOCRED, 0, &bp);
	if (error) {

		/*
		 * The inode does not contain anything useful, so it would
		 * be misleading to leave it on its hash chain. With mode
		 * still zero, it will be unlinked and returned to the free
		 * list by vput().
		 */

		vput(vp);
		*vpp = NULL;
		return (error);
	}
	cp = (char *)bp->b_data + (ino_to_fsbo(fs, ino) * EXT2_DINODE_SIZE(fs));
	ip->i_din.e2fs_din = pool_get(&ext2fs_dinode_pool, PR_WAITOK);
	e2fs_iload((struct ext2fs_dinode *)cp, ip->i_din.e2fs_din);
	ext2fs_set_inode_guid(ip);
	brelse(bp, 0);

	/* If the inode was deleted, reset all fields */
	if (ip->i_e2fs_dtime != 0) {
		ip->i_e2fs_mode = 0;
		(void)ext2fs_setsize(ip, 0);
		(void)ext2fs_setnblock(ip, 0);
		memset(ip->i_e2fs_blocks, 0, sizeof(ip->i_e2fs_blocks));
	}

	/*
	 * Initialize the vnode from the inode, check for aliases.
	 */

	error = ext2fs_vinit(mp, ext2fs_specop_p, ext2fs_fifoop_p, &vp);
	if (error) {
		vput(vp);
		*vpp = NULL;
		return (error);
	}
	/*
	 * Finish inode initialization now that aliasing has been resolved.
	 */

	ip->i_devvp = ump->um_devvp;
	vref(ip->i_devvp);

	/*
	 * Set up a generation number for this inode if it does not
	 * already have one. This should only happen on old filesystems.
	 */

	if (ip->i_e2fs_gen == 0) {
		if (++ext2gennumber < (u_long)time_second)
			ext2gennumber = time_second;
		ip->i_e2fs_gen = ext2gennumber;
		if ((vp->v_mount->mnt_flag & MNT_RDONLY) == 0)
			ip->i_flag |= IN_MODIFIED;
	}
	uvm_vnp_setsize(vp, ext2fs_size(ip));
	*vpp = vp;
	return (0);
}