On Wed, 2018-07-04 at 19:10 +0200, Marek Behún wrote:

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The comparison logical > item->logical + item->length in btrfs_map_logical_to_physical is wrong and should be instead logical >= item->logical + item->length For example, if item->logical = 4096 item->length = 4096 and we are looking for logical = 8192, it is not part of item (item is [4096, 8191]). But the comparison is false and we think we have found the correct item, although we should be searing in the right subtree.

This fixes some bugs I encountered.

Signed-off-by: Marek Behun marek.behun@nic.cz

fs/btrfs/chunk-map.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/btrfs/chunk-map.c b/fs/btrfs/chunk-map.c index beb6a4bb92..31619f6241 100644 --- a/fs/btrfs/chunk-map.c +++ b/fs/btrfs/chunk-map.c @@ -78,7 +78,7 @@ u64 btrfs_map_logical_to_physical(u64 logical)

            if (item->logical > logical)
                    node = node->rb_left;

•           else if (logical > item->logical + item->length)
  

•           else if (logical > item->logical + item->length - 1)
  

maybe logical >= item->logical + item->length ?

                    node = node->rb_right;