From 8c594ea81d7abbbffdda447b127f8ba8d76f319d Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Mon, 20 Apr 2009 15:50:10 -0400 Subject: [PATCH] Btrfs: use the right node in reada_for_balance reada_for_balance was using the wrong index into the path node array, so it wasn't reading the right blocks. We never directly used the results of the read done by this function because the btree search is started over at the end. This fixes reada_for_balance to reada in the correct node and to avoid searching past the last slot in the node. It also makes sure to hold the parent lock while we are finding the nodes to read. Signed-off-by: Chris Mason --- fs/btrfs/ctree.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c index e5b2533b691..a99f1c2a710 100644 --- a/fs/btrfs/ctree.c +++ b/fs/btrfs/ctree.c @@ -1325,12 +1325,12 @@ static noinline int reada_for_balance(struct btrfs_root *root, int ret = 0; int blocksize; - parent = path->nodes[level - 1]; + parent = path->nodes[level + 1]; if (!parent) return 0; nritems = btrfs_header_nritems(parent); - slot = path->slots[level]; + slot = path->slots[level + 1]; blocksize = btrfs_level_size(root, level); if (slot > 0) { @@ -1341,7 +1341,7 @@ static noinline int reada_for_balance(struct btrfs_root *root, block1 = 0; free_extent_buffer(eb); } - if (slot < nritems) { + if (slot + 1 < nritems) { block2 = btrfs_node_blockptr(parent, slot + 1); gen = btrfs_node_ptr_generation(parent, slot + 1); eb = btrfs_find_tree_block(root, block2, blocksize); @@ -1351,7 +1351,11 @@ static noinline int reada_for_balance(struct btrfs_root *root, } if (block1 || block2) { ret = -EAGAIN; + + /* release the whole path */ btrfs_release_path(root, path); + + /* read the blocks */ if (block1) readahead_tree_block(root, block1, blocksize, 0); if (block2) @@ -1361,7 +1365,7 @@ static noinline int reada_for_balance(struct btrfs_root *root, eb = read_tree_block(root, block1, blocksize, 0); free_extent_buffer(eb); } - if (block1) { + if (block2) { eb = read_tree_block(root, block2, blocksize, 0); free_extent_buffer(eb); } @@ -1481,12 +1485,15 @@ read_block_for_search(struct btrfs_trans_handle *trans, * of the btree by dropping locks before * we read. */ - btrfs_release_path(NULL, p); + btrfs_unlock_up_safe(p, level + 1); + btrfs_set_path_blocking(p); + if (tmp) free_extent_buffer(tmp); if (p->reada) reada_for_search(root, p, level, slot, key->objectid); + btrfs_release_path(NULL, p); tmp = read_tree_block(root, blocknr, blocksize, gen); if (tmp) free_extent_buffer(tmp); -- 2.20.1