xfs_bmap_btree.c

linux 内核源代码

{
	return ((xfs_fileoff_t)r->l0 &
		 XFS_MASK64LO(64 - BMBT_EXNTFLAG_BITLEN)) >> 9;
}

xfs_exntst_t
xfs_bmbt_get_state(
	xfs_bmbt_rec_host_t	*r)
{
	int	ext_flag;

	ext_flag = (int)((r->l0) >> (64 - BMBT_EXNTFLAG_BITLEN));
	return xfs_extent_state(xfs_bmbt_get_blockcount(r),
				ext_flag);
}

/* Endian flipping versions of the bmbt extraction functions */
void
xfs_bmbt_disk_get_all(
	xfs_bmbt_rec_t	*r,
	xfs_bmbt_irec_t *s)
{
	__xfs_bmbt_get_all(be64_to_cpu(r->l0), be64_to_cpu(r->l1), s);
}

/*
 * Extract the blockcount field from an on disk bmap extent record.
 */
xfs_filblks_t
xfs_bmbt_disk_get_blockcount(
	xfs_bmbt_rec_t	*r)
{
	return (xfs_filblks_t)(be64_to_cpu(r->l1) & XFS_MASK64LO(21));
}

/*
 * Extract the startoff field from a disk format bmap extent record.
 */
xfs_fileoff_t
xfs_bmbt_disk_get_startoff(
	xfs_bmbt_rec_t	*r)
{
	return ((xfs_fileoff_t)be64_to_cpu(r->l0) &
		 XFS_MASK64LO(64 - BMBT_EXNTFLAG_BITLEN)) >> 9;
}

/*
 * Increment cursor by one record at the level.
 * For nonzero levels the leaf-ward information is untouched.
 */
int						/* error */
xfs_bmbt_increment(
	xfs_btree_cur_t		*cur,
	int			level,
	int			*stat)		/* success/failure */
{
	xfs_bmbt_block_t	*block;
	xfs_buf_t		*bp;
	int			error;		/* error return value */
	xfs_fsblock_t		fsbno;
	int			lev;
	xfs_mount_t		*mp;
	xfs_trans_t		*tp;

	XFS_BMBT_TRACE_CURSOR(cur, ENTRY);
	XFS_BMBT_TRACE_ARGI(cur, level);
	ASSERT(level < cur->bc_nlevels);
	if (level < cur->bc_nlevels - 1)
		xfs_btree_readahead(cur, level, XFS_BTCUR_RIGHTRA);
	block = xfs_bmbt_get_block(cur, level, &bp);
#ifdef DEBUG
	if ((error = xfs_btree_check_lblock(cur, block, level, bp))) {
		XFS_BMBT_TRACE_CURSOR(cur, ERROR);
		return error;
	}
#endif
	if (++cur->bc_ptrs[level] <= be16_to_cpu(block->bb_numrecs)) {
		XFS_BMBT_TRACE_CURSOR(cur, EXIT);
		*stat = 1;
		return 0;
	}
	if (be64_to_cpu(block->bb_rightsib) == NULLDFSBNO) {
		XFS_BMBT_TRACE_CURSOR(cur, EXIT);
		*stat = 0;
		return 0;
	}
	for (lev = level + 1; lev < cur->bc_nlevels; lev++) {
		block = xfs_bmbt_get_block(cur, lev, &bp);
#ifdef DEBUG
		if ((error = xfs_btree_check_lblock(cur, block, lev, bp))) {
			XFS_BMBT_TRACE_CURSOR(cur, ERROR);
			return error;
		}
#endif
		if (++cur->bc_ptrs[lev] <= be16_to_cpu(block->bb_numrecs))
			break;
		if (lev < cur->bc_nlevels - 1)
			xfs_btree_readahead(cur, lev, XFS_BTCUR_RIGHTRA);
	}
	if (lev == cur->bc_nlevels) {
		XFS_BMBT_TRACE_CURSOR(cur, EXIT);
		*stat = 0;
		return 0;
	}
	tp = cur->bc_tp;
	mp = cur->bc_mp;
	for (block = xfs_bmbt_get_block(cur, lev, &bp); lev > level; ) {
		fsbno = be64_to_cpu(*XFS_BMAP_PTR_IADDR(block, cur->bc_ptrs[lev], cur));
		if ((error = xfs_btree_read_bufl(mp, tp, fsbno, 0, &bp,
				XFS_BMAP_BTREE_REF))) {
			XFS_BMBT_TRACE_CURSOR(cur, ERROR);
			return error;
		}
		lev--;
		xfs_btree_setbuf(cur, lev, bp);
		block = XFS_BUF_TO_BMBT_BLOCK(bp);
		if ((error = xfs_btree_check_lblock(cur, block, lev, bp))) {
			XFS_BMBT_TRACE_CURSOR(cur, ERROR);
			return error;
		}
		cur->bc_ptrs[lev] = 1;
	}
	XFS_BMBT_TRACE_CURSOR(cur, EXIT);
	*stat = 1;
	return 0;
}

/*
 * Insert the current record at the point referenced by cur.
 */
int					/* error */
xfs_bmbt_insert(
	xfs_btree_cur_t	*cur,
	int		*stat)		/* success/failure */
{
	int		error;		/* error return value */
	int		i;
	int		level;
	xfs_fsblock_t	nbno;
	xfs_btree_cur_t	*ncur;
	xfs_bmbt_rec_t	nrec;
	xfs_btree_cur_t	*pcur;

	XFS_BMBT_TRACE_CURSOR(cur, ENTRY);
	level = 0;
	nbno = NULLFSBLOCK;
	xfs_bmbt_disk_set_all(&nrec, &cur->bc_rec.b);
	ncur = NULL;
	pcur = cur;
	do {
		if ((error = xfs_bmbt_insrec(pcur, level++, &nbno, &nrec, &ncur,
				&i))) {
			if (pcur != cur)
				xfs_btree_del_cursor(pcur, XFS_BTREE_ERROR);
			XFS_BMBT_TRACE_CURSOR(cur, ERROR);
			return error;
		}
		XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
		if (pcur != cur && (ncur || nbno == NULLFSBLOCK)) {
			cur->bc_nlevels = pcur->bc_nlevels;
			cur->bc_private.b.allocated +=
				pcur->bc_private.b.allocated;
			pcur->bc_private.b.allocated = 0;
			ASSERT((cur->bc_private.b.firstblock != NULLFSBLOCK) ||
			       (cur->bc_private.b.ip->i_d.di_flags &
				XFS_DIFLAG_REALTIME));
			cur->bc_private.b.firstblock =
				pcur->bc_private.b.firstblock;
			ASSERT(cur->bc_private.b.flist ==
			       pcur->bc_private.b.flist);
			xfs_btree_del_cursor(pcur, XFS_BTREE_NOERROR);
		}
		if (ncur) {
			pcur = ncur;
			ncur = NULL;
		}
	} while (nbno != NULLFSBLOCK);
	XFS_BMBT_TRACE_CURSOR(cur, EXIT);
	*stat = i;
	return 0;
error0:
	XFS_BMBT_TRACE_CURSOR(cur, ERROR);
	return error;
}

/*
 * Log fields from the btree block header.
 */
void
xfs_bmbt_log_block(
	xfs_btree_cur_t		*cur,
	xfs_buf_t		*bp,
	int			fields)
{
	int			first;
	int			last;
	xfs_trans_t		*tp;
	static const short	offsets[] = {
		offsetof(xfs_bmbt_block_t, bb_magic),
		offsetof(xfs_bmbt_block_t, bb_level),
		offsetof(xfs_bmbt_block_t, bb_numrecs),
		offsetof(xfs_bmbt_block_t, bb_leftsib),
		offsetof(xfs_bmbt_block_t, bb_rightsib),
		sizeof(xfs_bmbt_block_t)
	};

	XFS_BMBT_TRACE_CURSOR(cur, ENTRY);
	XFS_BMBT_TRACE_ARGBI(cur, bp, fields);
	tp = cur->bc_tp;
	if (bp) {
		xfs_btree_offsets(fields, offsets, XFS_BB_NUM_BITS, &first,
				  &last);
		xfs_trans_log_buf(tp, bp, first, last);
	} else
		xfs_trans_log_inode(tp, cur->bc_private.b.ip,
			XFS_ILOG_FBROOT(cur->bc_private.b.whichfork));
	XFS_BMBT_TRACE_CURSOR(cur, EXIT);
}

/*
 * Log record values from the btree block.
 */
void
xfs_bmbt_log_recs(
	xfs_btree_cur_t		*cur,
	xfs_buf_t		*bp,
	int			rfirst,
	int			rlast)
{
	xfs_bmbt_block_t	*block;
	int			first;
	int			last;
	xfs_bmbt_rec_t		*rp;
	xfs_trans_t		*tp;

	XFS_BMBT_TRACE_CURSOR(cur, ENTRY);
	XFS_BMBT_TRACE_ARGBII(cur, bp, rfirst, rlast);
	ASSERT(bp);
	tp = cur->bc_tp;
	block = XFS_BUF_TO_BMBT_BLOCK(bp);
	rp = XFS_BMAP_REC_DADDR(block, 1, cur);
	first = (int)((xfs_caddr_t)&rp[rfirst - 1] - (xfs_caddr_t)block);
	last = (int)(((xfs_caddr_t)&rp[rlast] - 1) - (xfs_caddr_t)block);
	xfs_trans_log_buf(tp, bp, first, last);
	XFS_BMBT_TRACE_CURSOR(cur, EXIT);
}

int					/* error */
xfs_bmbt_lookup_eq(
	xfs_btree_cur_t	*cur,
	xfs_fileoff_t	off,
	xfs_fsblock_t	bno,
	xfs_filblks_t	len,
	int		*stat)		/* success/failure */
{
	cur->bc_rec.b.br_startoff = off;
	cur->bc_rec.b.br_startblock = bno;
	cur->bc_rec.b.br_blockcount = len;
	return xfs_bmbt_lookup(cur, XFS_LOOKUP_EQ, stat);
}

int					/* error */
xfs_bmbt_lookup_ge(
	xfs_btree_cur_t	*cur,
	xfs_fileoff_t	off,
	xfs_fsblock_t	bno,
	xfs_filblks_t	len,
	int		*stat)		/* success/failure */
{
	cur->bc_rec.b.br_startoff = off;
	cur->bc_rec.b.br_startblock = bno;
	cur->bc_rec.b.br_blockcount = len;
	return xfs_bmbt_lookup(cur, XFS_LOOKUP_GE, stat);
}

/*
 * Give the bmap btree a new root block.  Copy the old broot contents
 * down into a real block and make the broot point to it.
 */
int						/* error */
xfs_bmbt_newroot(
	xfs_btree_cur_t		*cur,		/* btree cursor */
	int			*logflags,	/* logging flags for inode */
	int			*stat)		/* return status - 0 fail */
{
	xfs_alloc_arg_t		args;		/* allocation arguments */
	xfs_bmbt_block_t	*block;		/* bmap btree block */
	xfs_buf_t		*bp;		/* buffer for block */
	xfs_bmbt_block_t	*cblock;	/* child btree block */
	xfs_bmbt_key_t		*ckp;		/* child key pointer */
	xfs_bmbt_ptr_t		*cpp;		/* child ptr pointer */
	int			error;		/* error return code */
#ifdef DEBUG
	int			i;		/* loop counter */
#endif
	xfs_bmbt_key_t		*kp;		/* pointer to bmap btree key */
	int			level;		/* btree level */
	xfs_bmbt_ptr_t		*pp;		/* pointer to bmap block addr */

	XFS_BMBT_TRACE_CURSOR(cur, ENTRY);
	level = cur->bc_nlevels - 1;
	block = xfs_bmbt_get_block(cur, level, &bp);
	/*
	 * Copy the root into a real block.
	 */
	args.mp = cur->bc_mp;
	pp = XFS_BMAP_PTR_IADDR(block, 1, cur);
	args.tp = cur->bc_tp;
	args.fsbno = cur->bc_private.b.firstblock;
	args.mod = args.minleft = args.alignment = args.total = args.isfl =
		args.userdata = args.minalignslop = 0;
	args.minlen = args.maxlen = args.prod = 1;
	args.wasdel = cur->bc_private.b.flags & XFS_BTCUR_BPRV_WASDEL;
	args.firstblock = args.fsbno;
	if (args.fsbno == NULLFSBLOCK) {
#ifdef DEBUG
		if ((error = xfs_btree_check_lptr_disk(cur, *pp, level))) {
			XFS_BMBT_TRACE_CURSOR(cur, ERROR);
			return error;
		}
#endif
		args.fsbno = be64_to_cpu(*pp);
		args.type = XFS_ALLOCTYPE_START_BNO;
	} else
		args.type = XFS_ALLOCTYPE_NEAR_BNO;
	if ((error = xfs_alloc_vextent(&args))) {
		XFS_BMBT_TRACE_CURSOR(cur, ERROR);
		return error;
	}
	if (args.fsbno == NULLFSBLOCK) {
		XFS_BMBT_TRACE_CURSOR(cur, EXIT);
		*stat = 0;
		return 0;
	}
	ASSERT(args.len == 1);
	cur->bc_private.b.firstblock = args.fsbno;
	cur->bc_private.b.allocated++;
	cur->bc_private.b.ip->i_d.di_nblocks++;
	XFS_TRANS_MOD_DQUOT_BYINO(args.mp, args.tp, cur->bc_private.b.ip,
			  XFS_TRANS_DQ_BCOUNT, 1L);
	bp = xfs_btree_get_bufl(args.mp, cur->bc_tp, args.fsbno, 0);
	cblock = XFS_BUF_TO_BMBT_BLOCK(bp);
	*cblock = *block;
	be16_add(&block->bb_level, 1);
	block->bb_numrecs = cpu_to_be16(1);
	cur->bc_nlevels++;
	cur->bc_ptrs[level + 1] = 1;
	kp = XFS_BMAP_KEY_IADDR(block, 1, cur);
	ckp = XFS_BMAP_KEY_IADDR(cblock, 1, cur);
	memcpy(ckp, kp, be16_to_cpu(cblock->bb_numrecs) * sizeof(*kp));
	cpp = XFS_BMAP_PTR_IADDR(cblock, 1, cur);
#ifdef DEBUG
	for (i = 0; i < be16_to_cpu(cblock->bb_numrecs); i++) {
		if ((error = xfs_btree_check_lptr_disk(cur, pp[i], level))) {
			XFS_BMBT_TRACE_CURSOR(cur, ERROR);
			return error;
		}
	}
#endif
	memcpy(cpp, pp, be16_to_cpu(cblock->bb_numrecs) * sizeof(*pp));
#ifdef DEBUG
	if ((error = xfs_btree_check_lptr(cur, args.fsbno, level))) {
		XFS_BMBT_TRACE_CURSOR(cur, ERROR);
		return error;
	}
#endif
	*pp = cpu_to_be64(args.fsbno);
	xfs_iroot_realloc(cur->bc_private.b.ip, 1 - be16_to_cpu(cblock->bb_numrecs),
		cur->bc_private.b.whichfork);
	xfs_btree_setbuf(cur, level, bp);
	/*
	 * Do all this logging at the end so that
	 * the root is at the right level.
	 */
	xfs_bmbt_log_block(cur, bp, XFS_BB_ALL_BITS);
	xfs_bmbt_log_keys(cur, bp, 1, be16_to_cpu(cblock->bb_numrecs));
	xfs_bmbt_log_ptrs(cur, bp, 1, be16_to_cpu(cblock->bb_numrecs));
	XFS_BMBT_TRACE_CURSOR(cur, EXIT);
	*logflags |=
		XFS_ILOG_CORE | XFS_ILOG_FBROOT(cur->bc_private.b.whichfork);
	*stat = 1;
	return 0;
}

/*
 * Set all the fields in a bmap extent record from the arguments.
 */
void
xfs_bmbt_set_allf(
	xfs_bmbt_rec_host_t	*r,
	xfs_fileoff_t		startoff,
	xfs_fsblock_t		startblock,
	xfs_filblks_t		blockcount,
	xfs_exntst_t		state)
{
	int		extent_flag = (state == XFS_EXT_NORM) ? 0 : 1;

	ASSERT(state == XFS_EXT_NORM || state == XFS_EXT_UNWRITTEN);
	ASSERT((startoff & XFS_MASK64HI(64-BMBT_STARTOFF_BITLEN)) == 0);
	ASSERT((blockcount & XFS_MASK64HI(64-BMBT_BLOCKCOUNT_BITLEN)) == 0);

#if XFS_BIG_BLKNOS
	ASSERT((startblock & XFS_MASK64HI(64-BMBT_STARTBLOCK_BITLEN)) == 0);

	r->l0 = ((xfs_bmbt_rec_base_t)extent_flag << 63) |
		((xfs_bmbt_rec_base_t)startoff << 9) |
		((xfs_bmbt_rec_base_t)startblock >> 43);
	r->l1 = ((xfs_bmbt_rec_base_t)startblock << 21) |
		((xfs_bmbt_rec_base_t)blockcount &
		(xfs_bmbt_rec_base_t)XFS_MASK64LO(21));
#else	/* !XFS_BIG_BLKNOS */
	if (ISNULLSTARTBLOCK(startblock)) {
		r->l0 = ((xfs_bmbt_rec_base_t)extent_flag << 63) |
			((xfs_bmbt_rec_base_t)startoff << 9) |
			 (xfs_bmbt_rec_base_t)XFS_MASK64LO(9);
		r->l1 = XFS_MASK64HI(11) |
			  ((xfs_bmbt_rec_base_t)startblock << 21) |
			  ((xfs_bmbt_rec_base_t)blockcount &
			   (xfs_bmbt_rec_base_t)XFS_MASK64LO(21));
	} else {
		r->l0 = ((xfs_bmbt_rec_base_t)extent_flag << 63) |
			((xfs_bmbt_rec_base_t)startoff << 9);
		r->l1 = ((xfs_bmbt_rec_base_t)startblock << 21) |
			 ((xfs_bmbt_rec_base_t)blockcount &
			 (xfs_bmbt_rec_base_t)XFS_MASK64LO(21));
	}
#endif	/* XFS_BIG_BLKNOS */
}

/*
 * Set all the fields in a bmap extent record from the uncompressed form.
 */
void
xfs_bmbt_set_all(
	xfs_bmbt_rec_host_t *r,
	xfs_bmbt_irec_t	*s)
{
	xfs_bmbt_set_allf(r, s->br_startoff, s->br_startblock,
			     s->br_blockcount, s->br_state);
}


/*
 * Set all the fields in a disk format bmap extent record from the arguments.
 */
void
xfs_bmbt_disk_set_allf(
	xfs_bmbt_rec_t		*r,
	xfs_fileoff_t		startoff,
	xfs_fsblock_t		startblock,
	xfs_filblks_t		blockcount,
	xfs_exntst_t		state)
{
	int			extent_flag = (state == XFS_EXT_NORM) ? 0 : 1;

	ASSERT(state == XFS_EXT_NORM || state == XFS_EXT_UNWRITTEN);
	ASSERT((startoff & XFS_MASK64HI(64-BMBT_STARTOFF_BITLEN)) == 0);
	ASSERT((blockcount & XFS_MASK64HI(64-BMBT_BLOCKCOUNT_BITLEN)) == 0);

#if XFS_BIG_BLKNOS
	ASSERT((startblock & XFS_MASK64HI(64-BMBT_STARTBLOCK_BITLEN)) == 0);

	r->l0 = cpu_to_be64(
		((xfs_bmbt_rec_base_t)extent_flag << 63) |
		 ((xfs_bmbt_rec_base_t)startoff << 9) |
		 ((xfs_bmbt_rec_base_t)startblock >> 43));
	r->l1 = cpu_to_be64(
		((xfs_bmbt_rec_base_t)startblock << 21) |
		 ((xfs_bmbt_rec_base_t)blockcount &
		  (xfs_bmbt_rec_base_t)XFS_MASK64LO(21)));
#else	/* !XFS_BIG_BLKNOS */
	if (ISNULLSTARTBLOCK(startblock)) {
		r->l0 = cpu_to_be64(
			((xfs_bmbt_rec_base_t)extent_flag << 63) |
			 ((xfs