Merge git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable

* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
  Btrfs: fix btrfs fallocate oops and deadlock
  Btrfs: use the right node in reada_for_balance
  Btrfs: fix oops on page->mapping->host during writepage
  Btrfs: add a priority queue to the async thread helpers
  Btrfs: use WRITE_SYNC for synchronous writes

1 files changed, 12 insertions, 5 deletions

diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index e5b2533b691a..a99f1c2a710d 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);