Commit d695c30a authored by Peng Zhang's avatar Peng Zhang Committed by Andrew Morton
Browse files

maple_tree: don't use MAPLE_ARANGE64_META_MAX to indicate no gap 

Patch series "Improve the validation for maple tree and some cleanup", v2.


This patch (of 7):

Do not use a special offset to indicate that there is no gap.  When there
is no gap, offset can point to any valid slots because its gap is 0.

Link: https://lkml.kernel.org/r/20230711035444.526-1-zhangpeng.00@bytedance.com
Link: https://lkml.kernel.org/r/20230711035444.526-3-zhangpeng.00@bytedance.com


Signed-off-by: default avatarPeng Zhang <zhangpeng.00@bytedance.com>
Reviewed-by: default avatarLiam R. Howlett <Liam.Howlett@oracle.com>
Tested-by: default avatarGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 86aa6998

include/linux/maple_tree.h

+0 −2
Original line number Diff line number Diff line
@@ -29,14 +29,12 @@ 
#define MAPLE_NODE_SLOTS	31	/* 256 bytes including ->parent */

#define MAPLE_RANGE64_SLOTS	16	/* 256 bytes */

#define MAPLE_ARANGE64_SLOTS	10	/* 240 bytes */

#define MAPLE_ARANGE64_META_MAX	15	/* Out of range for metadata */

#define MAPLE_ALLOC_SLOTS	(MAPLE_NODE_SLOTS - 1)

#else

/* 32bit sizes */

#define MAPLE_NODE_SLOTS	63	/* 256 bytes including ->parent */

#define MAPLE_RANGE64_SLOTS	32	/* 256 bytes */

#define MAPLE_ARANGE64_SLOTS	21	/* 240 bytes */

#define MAPLE_ARANGE64_META_MAX	31	/* Out of range for metadata */

#define MAPLE_ALLOC_SLOTS	(MAPLE_NODE_SLOTS - 2)

#endif /* defined(CONFIG_64BIT) || defined(BUILD_VDSO32_64) */

lib/maple_tree.c

+2 −11
Original line number Diff line number Diff line
@@ -1610,8 +1610,6 @@ ma_max_gap(struct maple_node *node, unsigned long *gaps, enum maple_type mt, 
 * mas_max_gap() - find the largest gap in a non-leaf node and set the slot.

 * @mas: The maple state.

 *

 * If the metadata gap is set to MAPLE_ARANGE64_META_MAX, there is no gap.

 *

 * Return: The gap value.

 */

static inline unsigned long mas_max_gap(struct ma_state *mas)
@@ -1628,9 +1626,6 @@ static inline unsigned long mas_max_gap(struct ma_state *mas) 
	node = mas_mn(mas);

	MAS_BUG_ON(mas, mt != maple_arange_64);

	offset = ma_meta_gap(node, mt);

	if (offset == MAPLE_ARANGE64_META_MAX)

		return 0;



	gaps = ma_gaps(node, mt);

	return gaps[offset];

}
@@ -1662,9 +1657,6 @@ static inline void mas_parent_gap(struct ma_state *mas, unsigned char offset, 
ascend:

	MAS_BUG_ON(mas, pmt != maple_arange_64);

	meta_offset = ma_meta_gap(pnode, pmt);

	if (meta_offset == MAPLE_ARANGE64_META_MAX)

		meta_gap = 0;

	else

	meta_gap = pgaps[meta_offset];



	pgaps[offset] = new;
@@ -1678,7 +1670,6 @@ static inline void mas_parent_gap(struct ma_state *mas, unsigned char offset, 


		ma_set_meta_gap(pnode, pmt, offset);

	} else if (new < meta_gap) {

		meta_offset = 15;

		new = ma_max_gap(pnode, pgaps, pmt, &meta_offset);

		ma_set_meta_gap(pnode, pmt, meta_offset);

	}
@@ -2076,7 +2067,7 @@ static inline void mab_mas_cp(struct maple_big_node *b_node, 
	end = j - 1;

	if (likely(!ma_is_leaf(mt) && mt_is_alloc(mas->tree))) {

		unsigned long max_gap = 0;

		unsigned char offset = 15;

		unsigned char offset = 0;



		gaps = ma_gaps(node, mt);

		do {