btr0btr.c

这是linux下运行的mysql软件包,可用于linux 下安装 php + mysql + apach 的网络配置

	} else {
		seg_header = root + PAGE_HEADER + PAGE_BTR_SEG_TOP;
	}

	space = buf_frame_get_space_id(page);
	page_no = buf_frame_get_page_no(page);
	
	fseg_free_page(seg_header, space, page_no, mtr);
}	

/******************************************************************
Frees a file page used in an index tree. NOTE: cannot free field external
storage pages because the page must contain info on its level. */

void
btr_page_free(
/*==========*/
	dict_tree_t*	tree,	/* in: index tree */
	page_t*		page,	/* in: page to be freed, x-latched */	
	mtr_t*		mtr)	/* in: mtr */
{
	ulint		level;

	ut_ad(mtr_memo_contains(mtr, buf_block_align(page),
			      				MTR_MEMO_PAGE_X_FIX));
	level = btr_page_get_level(page, mtr);
	
	btr_page_free_low(tree, page, level, mtr);
}	

/******************************************************************
Sets the child node file address in a node pointer. */
UNIV_INLINE
void
btr_node_ptr_set_child_page_no(
/*===========================*/
	rec_t*		rec,	/* in: node pointer record */
	const ulint*	offsets,/* in: array returned by rec_get_offsets() */
	ulint		page_no,/* in: child node address */
	mtr_t*		mtr)	/* in: mtr */
{
	byte*	field;
	ulint	len;

	ut_ad(rec_offs_validate(rec, NULL, offsets));
	ut_ad(0 < btr_page_get_level(buf_frame_align(rec), mtr));
	ut_ad(!rec_offs_comp(offsets) || rec_get_node_ptr_flag(rec));

	/* The child address is in the last field */	
	field = rec_get_nth_field(rec, offsets,
					rec_offs_n_fields(offsets) - 1, &len);

	ut_ad(len == 4);
	
	mlog_write_ulint(field, page_no, MLOG_4BYTES, mtr);
}

/****************************************************************
Returns the child page of a node pointer and x-latches it. */
static
page_t*
btr_node_ptr_get_child(
/*===================*/
				/* out: child page, x-latched */
	rec_t*		node_ptr,/* in: node pointer */
	const ulint*	offsets,/* in: array returned by rec_get_offsets() */
	mtr_t*		mtr)	/* in: mtr */
{
	ulint	page_no;
	ulint	space;
	page_t*	page;

	ut_ad(rec_offs_validate(node_ptr, NULL, offsets));
	space = buf_frame_get_space_id(node_ptr);
	page_no = btr_node_ptr_get_child_page_no(node_ptr, offsets);

	page = btr_page_get(space, page_no, RW_X_LATCH, mtr);
	
	return(page);
}

/****************************************************************
Returns the upper level node pointer to a page. It is assumed that mtr holds
an x-latch on the tree. */
static
rec_t*
btr_page_get_father_for_rec(
/*========================*/
				/* out: pointer to node pointer record,
				its page x-latched */
	dict_tree_t*	tree,	/* in: index tree */
	page_t*		page,	/* in: page: must contain at least one
				user record */
	rec_t*		user_rec,/* in: user_record on page */
	mtr_t*		mtr)	/* in: mtr */
{
	mem_heap_t*	heap;
	dtuple_t*	tuple;
	btr_cur_t	cursor;
	rec_t*		node_ptr;
	dict_index_t*	index;
	ulint		offsets_[REC_OFFS_NORMAL_SIZE];
	ulint*		offsets	= offsets_;
	*offsets_ = (sizeof offsets_) / sizeof *offsets_;

	ut_ad(mtr_memo_contains(mtr, dict_tree_get_lock(tree),
							MTR_MEMO_X_LOCK));
	ut_a(page_rec_is_user_rec(user_rec));
	
	ut_ad(dict_tree_get_page(tree) != buf_frame_get_page_no(page));

	heap = mem_heap_create(100);

	tuple = dict_tree_build_node_ptr(tree, user_rec, 0, heap,
					 btr_page_get_level(page, mtr));
	index = UT_LIST_GET_FIRST(tree->tree_indexes);

	/* In the following, we choose just any index from the tree as the
	first parameter for btr_cur_search_to_nth_level. */

	btr_cur_search_to_nth_level(index,
				btr_page_get_level(page, mtr) + 1,
				tuple, PAGE_CUR_LE,
				BTR_CONT_MODIFY_TREE, &cursor, 0, mtr);

	node_ptr = btr_cur_get_rec(&cursor);
	offsets = rec_get_offsets(node_ptr, index, offsets,
						ULINT_UNDEFINED, &heap);

	if (btr_node_ptr_get_child_page_no(node_ptr, offsets) !=
                                                buf_frame_get_page_no(page)) {
		rec_t*	print_rec;
		fputs("InnoDB: Dump of the child page:\n", stderr);
		buf_page_print(buf_frame_align(page));
		fputs("InnoDB: Dump of the parent page:\n", stderr);
		buf_page_print(buf_frame_align(node_ptr));

		fputs("InnoDB: Corruption of an index tree: table ", stderr);
		ut_print_name(stderr, NULL, index->table_name);
		fputs(", index ", stderr);
		ut_print_name(stderr, NULL, index->name);
		fprintf(stderr, ",\n"
"InnoDB: father ptr page no %lu, child page no %lu\n",
			(ulong)
			btr_node_ptr_get_child_page_no(node_ptr, offsets),
			(ulong) buf_frame_get_page_no(page));
		print_rec = page_rec_get_next(page_get_infimum_rec(page));
		offsets = rec_get_offsets(print_rec, index,
				offsets, ULINT_UNDEFINED, &heap);
		page_rec_print(print_rec, offsets);
		offsets = rec_get_offsets(node_ptr, index, offsets,
					ULINT_UNDEFINED, &heap);
		page_rec_print(node_ptr, offsets);

		fputs(
"InnoDB: You should dump + drop + reimport the table to fix the\n"
"InnoDB: corruption. If the crash happens at the database startup, see\n"
"InnoDB: http://dev.mysql.com/doc/mysql/en/Forcing_recovery.html about\n"
"InnoDB: forcing recovery. Then dump + drop + reimport.\n", stderr);
	}

	ut_a(btr_node_ptr_get_child_page_no(node_ptr, offsets) ==
						buf_frame_get_page_no(page));
	mem_heap_free(heap);

	return(node_ptr);
}

/****************************************************************
Returns the upper level node pointer to a page. It is assumed that
mtr holds an x-latch on the tree. */
static
rec_t*
btr_page_get_father_node_ptr(
/*=========================*/
				/* out: pointer to node pointer record */
	dict_tree_t*	tree,	/* in: index tree */
	page_t*		page,	/* in: page: must contain at least one
				user record */
	mtr_t*		mtr)	/* in: mtr */
{
	return(btr_page_get_father_for_rec(tree, page,
		page_rec_get_next(page_get_infimum_rec(page)), mtr));
}

/****************************************************************
Creates the root node for a new index tree. */

ulint
btr_create(
/*=======*/
			/* out: page number of the created root, FIL_NULL if
			did not succeed */
	ulint	type,	/* in: type of the index */
	ulint	space,	/* in: space where created */
	dulint	index_id,/* in: index id */
	ulint	comp,	/* in: nonzero=compact page format */
	mtr_t*	mtr)	/* in: mini-transaction handle */
{
	ulint		page_no;
	buf_frame_t*	ibuf_hdr_frame;
	buf_frame_t*	frame;
	page_t*		page;

	/* Create the two new segments (one, in the case of an ibuf tree) for
	the index tree; the segment headers are put on the allocated root page
	(for an ibuf tree, not in the root, but on a separate ibuf header
	page) */

	if (type & DICT_IBUF) {
		/* Allocate first the ibuf header page */
		ibuf_hdr_frame = fseg_create(space, 0,
				IBUF_HEADER + IBUF_TREE_SEG_HEADER, mtr);

#ifdef UNIV_SYNC_DEBUG
		buf_page_dbg_add_level(ibuf_hdr_frame, SYNC_TREE_NODE_NEW);
#endif /* UNIV_SYNC_DEBUG */
		ut_ad(buf_frame_get_page_no(ibuf_hdr_frame)
 						== IBUF_HEADER_PAGE_NO);
		/* Allocate then the next page to the segment: it will be the
 		tree root page */

 		page_no = fseg_alloc_free_page(
				ibuf_hdr_frame + IBUF_HEADER
 				+ IBUF_TREE_SEG_HEADER, IBUF_TREE_ROOT_PAGE_NO,
				FSP_UP, mtr);
		ut_ad(page_no == IBUF_TREE_ROOT_PAGE_NO);

		frame = buf_page_get(space, page_no, RW_X_LATCH, mtr);
	} else {
		frame = fseg_create(space, 0, PAGE_HEADER + PAGE_BTR_SEG_TOP,
									mtr);
	}
	
	if (frame == NULL) {

		return(FIL_NULL);
	}

	page_no = buf_frame_get_page_no(frame);
	
#ifdef UNIV_SYNC_DEBUG
	buf_page_dbg_add_level(frame, SYNC_TREE_NODE_NEW);
#endif /* UNIV_SYNC_DEBUG */

	if (type & DICT_IBUF) {
		/* It is an insert buffer tree: initialize the free list */

		ut_ad(page_no == IBUF_TREE_ROOT_PAGE_NO);
		
		flst_init(frame + PAGE_HEADER + PAGE_BTR_IBUF_FREE_LIST, mtr);
	} else {	
		/* It is a non-ibuf tree: create a file segment for leaf
		pages */
		fseg_create(space, page_no, PAGE_HEADER + PAGE_BTR_SEG_LEAF,
									mtr);
		/* The fseg create acquires a second latch on the page,
		therefore we must declare it: */
#ifdef UNIV_SYNC_DEBUG
		buf_page_dbg_add_level(frame, SYNC_TREE_NODE_NEW);
#endif /* UNIV_SYNC_DEBUG */
	}
	
	/* Create a new index page on the the allocated segment page */
	page = page_create(frame, mtr, comp);
	buf_block_align(page)->check_index_page_at_flush = TRUE;

	/* Set the index id of the page */
	btr_page_set_index_id(page, index_id, mtr);

	/* Set the level of the new index page */
	btr_page_set_level(page, 0, mtr);
	
	/* Set the next node and previous node fields */
	btr_page_set_next(page, FIL_NULL, mtr);
	btr_page_set_prev(page, FIL_NULL, mtr);

	/* We reset the free bits for the page to allow creation of several
	trees in the same mtr, otherwise the latch on a bitmap page would
	prevent it because of the latching order */
	
	ibuf_reset_free_bits_with_type(type, page);

	/* In the following assertion we test that two records of maximum
	allowed size fit on the root page: this fact is needed to ensure
	correctness of split algorithms */

	ut_ad(page_get_max_insert_size(page, 2) > 2 * BTR_PAGE_MAX_REC_SIZE);

	return(page_no);
}

/****************************************************************
Frees a B-tree except the root page, which MUST be freed after this
by calling btr_free_root. */

void
btr_free_but_not_root(
/*==================*/
	ulint	space,		/* in: space where created */
	ulint	root_page_no)	/* in: root page number */
{
	ibool	finished;
	page_t*	root;
	mtr_t	mtr;

leaf_loop:	
	mtr_start(&mtr);
	
	root = btr_page_get(space, root_page_no, RW_X_LATCH, &mtr);	

	/* NOTE: page hash indexes are dropped when a page is freed inside
	fsp0fsp. */

	finished = fseg_free_step(
				root + PAGE_HEADER + PAGE_BTR_SEG_LEAF, &mtr);
	mtr_commit(&mtr);

	if (!finished) {

		goto leaf_loop;
	}
top_loop:
	mtr_start(&mtr);
	
	root = btr_page_get(space, root_page_no, RW_X_LATCH, &mtr);	

	finished = fseg_free_step_not_header(
				root + PAGE_HEADER + PAGE_BTR_SEG_TOP, &mtr);
	mtr_commit(&mtr);

	if (!finished) {

		goto top_loop;
	}	
}

/****************************************************************
Frees the B-tree root page. Other tree MUST already have been freed. */

void
btr_free_root(
/*==========*/
	ulint	space,		/* in: space where created */
	ulint	root_page_no,	/* in: root page number */
	mtr_t*	mtr)		/* in: a mini-transaction which has already
				been started */
{
	ibool	finished;
	page_t*	root;

	root = btr_page_get(space, root_page_no, RW_X_LATCH, mtr);

	btr_search_drop_page_hash_index(root);	
top_loop:	
	finished = fseg_free_step(
				root + PAGE_HEADER + PAGE_BTR_SEG_TOP, mtr);
	if (!finished) {

		goto top_loop;
	}	
}

/*****************************************************************
Reorganizes an index page. */
static
void
btr_page_reorganize_low(
/*====================*/
	ibool		recovery,/* in: TRUE if called in recovery:
				locks should not be updated, i.e.,
				there cannot exist locks on the
				page, and a hash index should not be
				dropped: it cannot exist */
	page_t*		page,	/* in: page to be reorganized */
	dict_index_t*	index,	/* in: record descriptor */
	mtr_t*		mtr)	/* in: mtr */
{
	page_t*	new_page;
	ulint	log_mode;
	ulint	data_size1;
	ulint	data_size2;
	ulint	max_ins_size1;
	ulint	max_ins_size2;

	ut_ad(mtr_memo_contains(mtr, buf_block_align(page),
			      				MTR_MEMO_PAGE_X_FIX));
	ut_ad(!!page_is_comp(page) == index->table->comp);
	data_size1 = page_get_data_size(page);
	max_ins_size1 = page_get_max_insert_size_after_reorganize(page, 1);

	/* Write the log record */
	mlog_open_and_write_index(mtr, page, index, page_is_comp(page)
			? MLOG_COMP_PAGE_REORGANIZE
			: MLOG_PAGE_REORGANIZE, 0);

	/* Turn logging off */
	log_mode = mtr_set_log_mode(mtr, MTR_LOG_NONE);

	new_page = buf_frame_alloc();

	/* Copy the old page to temporary space */
	buf_frame_copy(new_page, page);

	if (!recovery) {
		btr_search_drop_page_hash_index(page);
	}

	/* Recreate the page: note that global data on page (possible
	segment headers, next page-field, etc.) is preserved intact */

	page_create(page, mtr, page_is_comp(page));
	buf_block_align(page)->check_index_page_at_flush = TRUE;
	
	/* Copy the records from the temporary space to the recreated page;
	do not copy the lock bits yet */

	page_copy_rec_list_end_no_locks(page, new_page,
				page_get_infimum_rec(new_page), index, mtr);
	/* Copy max trx id to recreated page */
	page_set_max_trx_id(page, page_get_max_trx_id(new_page));
	
	if (!recovery) {
		/* Update the record lock bitmaps */
		lock_move_reorganize_page(page, new_page);
	}

	data_size2 = page_get_data_size(page);
	max_ins_size2 = page_get_max_insert_size_after_reorganize(page, 1);

	if (data_size1 != data_size2 || max_ins_size1 != max_ins_size2) {
		buf_page_print(page);
		buf_page_print(new_page);
	        fprintf(stderr,
"InnoDB: Error: page old data size %lu new data size %lu\n"
"InnoDB: Error: page old max ins size %lu new max ins size %lu\n"
"InnoDB: Submit a detailed bug report to http://bugs.mysql.com\n",
			(unsigned long) data_size1, (unsigned long) data_size2,
			(unsigned long) max_ins_size1,
			(unsigned long) max_ins_size2);
	}

	buf_frame_free(new_page);

	/* Restore logging mode */
	mtr_set_log_mode(mtr, log_mode);
}

/*****************************************************************
Reorganizes an index page. */

void
btr_page_reorganize(
/*================*/
	page_t*		page,	/* in: page to be reorganized */
	dict_index_t*	index,	/* in: record descriptor */
	mtr_t*		mtr)	/* in: mtr */
{
	btr_page_reorganize_low(FALSE, page, index, mtr);
}