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	dm btree remove: fix bug in redistribute3
redistribute3() shares entries out across 3 nodes. Some entries were being moved the wrong way, breaking the ordering. This manifested as a BUG() in dm-btree-remove.c:shift() when entries were removed from the btree. For additional context see: https://www.redhat.com/archives/dm-devel/2015-May/msg00113.html Signed-off-by: Dennis Yang <shinrairis@gmail.com> Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org
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					 1 changed files with 3 additions and 3 deletions
				
			
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					@ -309,8 +309,8 @@ static void redistribute3(struct dm_btree_info *info, struct btree_node *parent,
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		if (s < 0 && nr_center < -s) {
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							if (s < 0 && nr_center < -s) {
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			/* not enough in central node */
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								/* not enough in central node */
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			shift(left, center, nr_center);
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								shift(left, center, -nr_center);
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			s = nr_center - target;
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								s += nr_center;
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			shift(left, right, s);
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								shift(left, right, s);
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			nr_right += s;
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								nr_right += s;
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		} else
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							} else
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					@ -323,7 +323,7 @@ static void redistribute3(struct dm_btree_info *info, struct btree_node *parent,
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		if (s > 0 && nr_center < s) {
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							if (s > 0 && nr_center < s) {
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			/* not enough in central node */
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								/* not enough in central node */
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			shift(center, right, nr_center);
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								shift(center, right, nr_center);
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			s = target - nr_center;
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								s -= nr_center;
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			shift(left, right, s);
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								shift(left, right, s);
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			nr_left -= s;
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								nr_left -= s;
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		} else
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							} else
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