Btrfs: Reduce stack usage in the resizer, fix 32 bit compiles

Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 15 insertions, 5 deletions

diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 1ad611b9f61b..02721eea9a7a 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -481,12 +481,10 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
         struct btrfs_transaction *cur_trans;
         struct btrfs_transaction *prev_trans = NULL;
         struct list_head dirty_fs_roots;
-        struct extent_map_tree pinned_copy;
+        struct extent_map_tree *pinned_copy;
         DEFINE_WAIT(wait);
         int ret;
 
-        extent_map_tree_init(&pinned_copy,
-                             root->fs_info->btree_inode->i_mapping, GFP_NOFS);
         INIT_LIST_HEAD(&dirty_fs_roots);
 
         mutex_lock(&root->fs_info->trans_mutex);
@@ -507,6 +505,14 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
                 mutex_lock(&root->fs_info->fs_mutex);
                 return 0;
         }
+
+        pinned_copy = kmalloc(sizeof(*pinned_copy), GFP_NOFS);
+        if (!pinned_copy)
+                return -ENOMEM;
+
+        extent_map_tree_init(pinned_copy,
+                             root->fs_info->btree_inode->i_mapping, GFP_NOFS);
+
         trans->transaction->in_commit = 1;
         cur_trans = trans->transaction;
         if (cur_trans->list.prev != &root->fs_info->trans_list) {
@@ -568,16 +574,20 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
                             &root->fs_info->super_copy, 0,
                             sizeof(root->fs_info->super_copy));
 
-        btrfs_copy_pinned(root, &pinned_copy);
+        btrfs_copy_pinned(root, pinned_copy);
 
         mutex_unlock(&root->fs_info->trans_mutex);
         mutex_unlock(&root->fs_info->fs_mutex);
         ret = btrfs_write_and_wait_transaction(trans, root);
         BUG_ON(ret);
         write_ctree_super(trans, root);
+
         mutex_lock(&root->fs_info->fs_mutex);
-        btrfs_finish_extent_commit(trans, root, &pinned_copy);
+        btrfs_finish_extent_commit(trans, root, pinned_copy);
         mutex_lock(&root->fs_info->trans_mutex);
+
+        kfree(pinned_copy);
+
         cur_trans->commit_done = 1;
         root->fs_info->last_trans_committed = cur_trans->transid;
         wake_up(&cur_trans->commit_wait);