diff options
| -rw-r--r-- | fs/btrfs/ctree.c | 39 |
1 files changed, 36 insertions, 3 deletions
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c index a99f1c2..fedf8b9 100644 --- a/fs/btrfs/ctree.c +++ b/fs/btrfs/ctree.c @@ -1469,6 +1469,7 @@ read_block_for_search(struct btrfs_trans_handle *trans, u32 blocksize; struct extent_buffer *b = *eb_ret; struct extent_buffer *tmp; + int ret; blocknr = btrfs_node_blockptr(b, slot); gen = btrfs_node_ptr_generation(b, slot); @@ -1476,6 +1477,10 @@ read_block_for_search(struct btrfs_trans_handle *trans, tmp = btrfs_find_tree_block(root, blocknr, blocksize); if (tmp && btrfs_buffer_uptodate(tmp, gen)) { + /* + * we found an up to date block without sleeping, return + * right away + */ *eb_ret = tmp; return 0; } @@ -1483,7 +1488,9 @@ read_block_for_search(struct btrfs_trans_handle *trans, /* * reduce lock contention at high levels * of the btree by dropping locks before - * we read. + * we read. Don't release the lock on the current + * level because we need to walk this node to figure + * out which blocks to read. */ btrfs_unlock_up_safe(p, level + 1); btrfs_set_path_blocking(p); @@ -1494,10 +1501,21 @@ read_block_for_search(struct btrfs_trans_handle *trans, reada_for_search(root, p, level, slot, key->objectid); btrfs_release_path(NULL, p); + + ret = -EAGAIN; tmp = read_tree_block(root, blocknr, blocksize, gen); - if (tmp) + if (tmp) { + /* + * If the read above didn't mark this buffer up to date, + * it will never end up being up to date. Set ret to EIO now + * and give up so that our caller doesn't loop forever + * on our EAGAINs. + */ + if (!btrfs_buffer_uptodate(tmp, 0)) + ret = -EIO; free_extent_buffer(tmp); - return -EAGAIN; + } + return ret; } /* @@ -1696,6 +1714,9 @@ cow_done: if (ret == -EAGAIN) goto again; + if (ret == -EIO) + goto done; + if (!p->skip_locking) { int lret; @@ -1738,6 +1759,8 @@ done: */ if (!p->leave_spinning) btrfs_set_path_blocking(p); + if (ret < 0) + btrfs_release_path(root, p); return ret; } @@ -4212,6 +4235,11 @@ again: if (ret == -EAGAIN) goto again; + if (ret < 0) { + btrfs_release_path(root, path); + goto done; + } + if (!path->skip_locking) { ret = btrfs_try_spin_lock(next); if (!ret) { @@ -4246,6 +4274,11 @@ again: if (ret == -EAGAIN) goto again; + if (ret < 0) { + btrfs_release_path(root, path); + goto done; + } + if (!path->skip_locking) { btrfs_assert_tree_locked(path->nodes[level]); ret = btrfs_try_spin_lock(next); |
