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

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

1 files changed, 38 insertions, 36 deletions

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 91c2b27d9689..6137f06091e8 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -751,7 +751,7 @@ again:
 
                 if (found_objectid != root_objectid) {
                         total_count = 2;
-                        break;
+                        goto out;
                 }
                 total_count = 1;
                 path->slots[0]++;
@@ -760,8 +760,6 @@ again:
                 total_count = 0;
                 goto out;
         }
-        if (total_count > 1)
-                goto out;
         if (level >= 0 && root->node == count_path->nodes[level])
                 goto out;
         level++;
@@ -2109,22 +2107,23 @@ static int relocate_inode_pages(struct inode *inode, u64 start, u64 len)
         u64 delalloc_start;
         u64 existing_delalloc;
         unsigned long last_index;
-        unsigned long first_index;
         unsigned long i;
         struct page *page;
         struct btrfs_root *root = BTRFS_I(inode)->root;
         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
-        struct file_ra_state ra;
+        struct file_ra_state *ra;
+
+        ra = kzalloc(sizeof(*ra), GFP_NOFS);
 
         mutex_lock(&inode->i_mutex);
-        first_index = start >> PAGE_CACHE_SHIFT;
+        i = start >> PAGE_CACHE_SHIFT;
         last_index = (start + len - 1) >> PAGE_CACHE_SHIFT;
 
-        memset(&ra, 0, sizeof(ra));
-        file_ra_state_init(&ra, inode->i_mapping);
-        btrfs_force_ra(inode->i_mapping, &ra, NULL, first_index, last_index);
+        file_ra_state_init(ra, inode->i_mapping);
+        btrfs_force_ra(inode->i_mapping, ra, NULL, i, last_index);
+        kfree(ra);
 
-        for (i = first_index; i <= last_index; i++) {
+        for (; i <= last_index; i++) {
                 page = grab_cache_page(inode->i_mapping, i);
                 if (!page)
                         goto out_unlock;
@@ -2167,27 +2166,43 @@ out_unlock:
         return 0;
 }
 
+/*
+ * note, this releases the path
+ */
 static int relocate_one_reference(struct btrfs_root *extent_root,
                                   struct btrfs_path *path,
-                                  struct btrfs_key *extent_key,
-                                  u64 ref_root, u64 ref_gen, u64 ref_objectid,
-                                  u64 ref_offset)
+                                  struct btrfs_key *extent_key)
 {
         struct inode *inode;
         struct btrfs_root *found_root;
-        struct btrfs_key root_location;
+        struct btrfs_key *root_location;
+        struct btrfs_extent_ref *ref;
+        u64 ref_root;
+        u64 ref_gen;
+        u64 ref_objectid;
+        u64 ref_offset;
         int ret;
 
-        root_location.objectid = ref_root;
+        ref = btrfs_item_ptr(path->nodes[0], path->slots[0],
+                             struct btrfs_extent_ref);
+        ref_root = btrfs_ref_root(path->nodes[0], ref);
+        ref_gen = btrfs_ref_generation(path->nodes[0], ref);
+        ref_objectid = btrfs_ref_objectid(path->nodes[0], ref);
+        ref_offset = btrfs_ref_offset(path->nodes[0], ref);
+        btrfs_release_path(extent_root, path);
+
+        root_location = kmalloc(sizeof(*root_location), GFP_NOFS);
+        root_location->objectid = ref_root;
         if (ref_gen == 0)
-                root_location.offset = 0;
+                root_location->offset = 0;
         else
-                root_location.offset = (u64)-1;
-        root_location.type = BTRFS_ROOT_ITEM_KEY;
+                root_location->offset = (u64)-1;
+        root_location->type = BTRFS_ROOT_ITEM_KEY;
 
         found_root = btrfs_read_fs_root_no_name(extent_root->fs_info,
-                                                &root_location);
+                                                root_location);
         BUG_ON(!found_root);
+        kfree(root_location);
 
         if (ref_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
                 mutex_unlock(&extent_root->fs_info->fs_mutex);
@@ -2259,12 +2274,7 @@ static int relocate_one_extent(struct btrfs_root *extent_root,
 {
         struct btrfs_key key;
         struct btrfs_key found_key;
-        struct btrfs_extent_ref *ref;
         struct extent_buffer *leaf;
-        u64 ref_root;
-        u64 ref_gen;
-        u64 ref_objectid;
-        u64 ref_offset;
         u32 nritems;
         u32 item_size;
         int ret = 0;
@@ -2297,17 +2307,7 @@ static int relocate_one_extent(struct btrfs_root *extent_root,
                 key.offset = found_key.offset + 1;
                 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
 
-                ref = btrfs_item_ptr(leaf, path->slots[0],
-                                     struct btrfs_extent_ref);
-                ref_root = btrfs_ref_root(leaf, ref);
-                ref_gen = btrfs_ref_generation(leaf, ref);
-                ref_objectid = btrfs_ref_objectid(leaf, ref);
-                ref_offset = btrfs_ref_offset(leaf, ref);
-                btrfs_release_path(extent_root, path);
-
-                ret = relocate_one_reference(extent_root, path,
-                                             extent_key, ref_root, ref_gen,
-                                             ref_objectid, ref_offset);
+                ret = relocate_one_reference(extent_root, path, extent_key);
                 if (ret)
                         goto out;
         }
@@ -2354,7 +2354,6 @@ int btrfs_shrink_extent_tree(struct btrfs_root *root, u64 new_size)
         struct btrfs_path *path;
         u64 cur_byte;
         u64 total_found;
-        u64 ptr;
         struct btrfs_fs_info *info = root->fs_info;
         struct extent_map_tree *block_group_cache;
         struct btrfs_key key;
@@ -2377,6 +2376,7 @@ again:
         key.offset = 0;
         key.type = 0;
         while(1) {
+
                 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
                 if (ret < 0)
                         goto out;
@@ -2441,6 +2441,8 @@ next:
         key.offset = 0;
         key.type = 0;
         while(1) {
+                u64 ptr;
+
                 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
                 if (ret < 0)
                         goto out;