Commit ef49b7b3 authored by Sidhartha Kumar's avatar Sidhartha Kumar Committed by Andrew Morton
Browse files

maple_tree: fix MAPLE_PARENT_RANGE32 and parent pointer docs 

MAPLE_PARENT_RANGE32 should be 0x02 as a 32 bit node is indicated by the
bit pattern 0b010 which is the hex value 0x02.  There are no users
currently, so there is no associated bug with this wrong value.

Fix typo Note -> Node and replace x with b to indicate binary values.

Link: https://lkml.kernel.org/r/20250826151344.403286-1-sidhartha.kumar@oracle.com


Fixes: 54a611b6 ("Maple Tree: add new data structure")
Signed-off-by: default avatarSidhartha Kumar <sidhartha.kumar@oracle.com>
Reviewed-by: default avatarLiam R. Howlett <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent e76e09bd

include/linux/maple_tree.h

+8 −8
Original line number Diff line number Diff line
@@ -57,17 +57,17 @@ 
 * MT_FLAGS_ALLOC_RANGE flag.

 *

 *  Node types:

 *   0x??1 = Root

 *   0x?00 = 16 bit nodes

 *   0x010 = 32 bit nodes

 *   0x110 = 64 bit nodes

 *   0b??1 = Root

 *   0b?00 = 16 bit nodes

 *   0b010 = 32 bit nodes

 *   0b110 = 64 bit nodes

 *

 *  Slot size and location in the parent pointer:

 *   type  : slot location

 *   0x??1 : Root

 *   0x?00 : 16 bit values, type in 0-1, slot in 2-6

 *   0x010 : 32 bit values, type in 0-2, slot in 3-6

 *   0x110 : 64 bit values, type in 0-2, slot in 3-6

 *   0b??1 : Root

 *   0b?00 : 16 bit values, type in 0-1, slot in 2-6

 *   0b010 : 32 bit values, type in 0-2, slot in 3-6

 *   0b110 : 64 bit values, type in 0-2, slot in 3-6

 */



/*

lib/maple_tree.c

+6 −6
Original line number Diff line number Diff line
@@ -405,11 +405,11 @@ static __always_inline bool mt_is_alloc(struct maple_tree *mt) 
 * a reuse of the last bit in the node type.  This is possible by using bit 1 to

 * indicate if bit 2 is part of the type or the slot.

 *

 * Note types:

 *  0x??1 = Root

 *  0x?00 = 16 bit nodes

 *  0x010 = 32 bit nodes

 *  0x110 = 64 bit nodes

 * Node types:

 *  0b??1 = Root

 *  0b?00 = 16 bit nodes

 *  0b010 = 32 bit nodes

 *  0b110 = 64 bit nodes

 *

 * Slot size and alignment

 *  0b??1 : Root
@@ -427,7 +427,7 @@ static __always_inline bool mt_is_alloc(struct maple_tree *mt) 
#define MAPLE_PARENT_16B_SLOT_MASK	0xFC



#define MAPLE_PARENT_RANGE64		0x06

#define MAPLE_PARENT_RANGE32		0x04

#define MAPLE_PARENT_RANGE32		0x02

#define MAPLE_PARENT_NOT_RANGE16	0x02



/*