1 files changed, 30 insertions, 27 deletions

diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index c3df14ce2cc2..9ac171599258 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -200,7 +200,6 @@ int btrfs_copy_root(struct btrfs_trans_handle *trans,
                       struct extent_buffer **cow_ret, u64 new_root_objectid)
 {
         struct extent_buffer *cow;
-        u32 nritems;
         int ret = 0;
         int level;
         struct btrfs_disk_key disk_key;
@@ -210,7 +209,6 @@ int btrfs_copy_root(struct btrfs_trans_handle *trans,
         WARN_ON(root->ref_cows && trans->transid != root->last_trans);
 
         level = btrfs_header_level(buf);
-        nritems = btrfs_header_nritems(buf);
         if (level == 0)
                 btrfs_item_key(buf, &disk_key, 0);
         else
@@ -1008,7 +1006,6 @@ static noinline int balance_level(struct btrfs_trans_handle *trans,
         int wret;
         int pslot;
         int orig_slot = path->slots[level];
-        int err_on_enospc = 0;
         u64 orig_ptr;
 
         if (level == 0)
@@ -1071,8 +1068,7 @@ static noinline int balance_level(struct btrfs_trans_handle *trans,
             BTRFS_NODEPTRS_PER_BLOCK(root) / 4)
                 return 0;
 
-        if (btrfs_header_nritems(mid) < 2)
-                err_on_enospc = 1;
+        btrfs_header_nritems(mid);
 
         left = read_node_slot(root, parent, pslot - 1);
         if (left) {
@@ -1103,8 +1099,7 @@ static noinline int balance_level(struct btrfs_trans_handle *trans,
                 wret = push_node_left(trans, root, left, mid, 1);
                 if (wret < 0)
                         ret = wret;
-                if (btrfs_header_nritems(mid) < 2)
-                        err_on_enospc = 1;
+                btrfs_header_nritems(mid);
         }
 
         /*
@@ -1224,14 +1219,12 @@ static noinline int push_nodes_for_insert(struct btrfs_trans_handle *trans,
         int wret;
         int pslot;
         int orig_slot = path->slots[level];
-        u64 orig_ptr;
 
         if (level == 0)
                 return 1;
 
         mid = path->nodes[level];
         WARN_ON(btrfs_header_generation(mid) != trans->transid);
-        orig_ptr = btrfs_node_blockptr(mid, orig_slot);
 
         if (level < BTRFS_MAX_LEVEL - 1)
                 parent = path->nodes[level + 1];
@@ -1577,13 +1570,33 @@ read_block_for_search(struct btrfs_trans_handle *trans,
         blocksize = btrfs_level_size(root, level - 1);
 
         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;
+        if (tmp) {
+                if (btrfs_buffer_uptodate(tmp, 0)) {
+                        if (btrfs_buffer_uptodate(tmp, gen)) {
+                                /*
+                                 * we found an up to date block without
+                                 * sleeping, return
+                                 * right away
+                                 */
+                                *eb_ret = tmp;
+                                return 0;
+                        }
+                        /* the pages were up to date, but we failed
+                         * the generation number check.  Do a full
+                         * read for the generation number that is correct.
+                         * We must do this without dropping locks so
+                         * we can trust our generation number
+                         */
+                        free_extent_buffer(tmp);
+                        tmp = read_tree_block(root, blocknr, blocksize, gen);
+                        if (tmp && btrfs_buffer_uptodate(tmp, gen)) {
+                                *eb_ret = tmp;
+                                return 0;
+                        }
+                        free_extent_buffer(tmp);
+                        btrfs_release_path(NULL, p);
+                        return -EIO;
+                }
         }
 
         /*
@@ -1596,8 +1609,7 @@ read_block_for_search(struct btrfs_trans_handle *trans,
         btrfs_unlock_up_safe(p, level + 1);
         btrfs_set_path_blocking(p);
 
-        if (tmp)
-                free_extent_buffer(tmp);
+        free_extent_buffer(tmp);
         if (p->reada)
                 reada_for_search(root, p, level, slot, key->objectid);
 
@@ -2548,7 +2560,6 @@ static noinline int __push_leaf_left(struct btrfs_trans_handle *trans,
 {
         struct btrfs_disk_key disk_key;
         struct extent_buffer *right = path->nodes[0];
-        int slot;
         int i;
         int push_space = 0;
         int push_items = 0;
@@ -2560,8 +2571,6 @@ static noinline int __push_leaf_left(struct btrfs_trans_handle *trans,
         u32 this_item_size;
         u32 old_left_item_size;
 
-        slot = path->slots[1];
-
         if (empty)
                 nr = min(right_nritems, max_slot);
         else
@@ -3330,7 +3339,6 @@ int btrfs_truncate_item(struct btrfs_trans_handle *trans,
 {
         int ret = 0;
         int slot;
-        int slot_orig;
         struct extent_buffer *leaf;
         struct btrfs_item *item;
         u32 nritems;
@@ -3340,7 +3348,6 @@ int btrfs_truncate_item(struct btrfs_trans_handle *trans,
         unsigned int size_diff;
         int i;
 
-        slot_orig = path->slots[0];
         leaf = path->nodes[0];
         slot = path->slots[0];
 
@@ -3445,7 +3452,6 @@ int btrfs_extend_item(struct btrfs_trans_handle *trans,
 {
         int ret = 0;
         int slot;
-        int slot_orig;
         struct extent_buffer *leaf;
         struct btrfs_item *item;
         u32 nritems;
@@ -3454,7 +3460,6 @@ int btrfs_extend_item(struct btrfs_trans_handle *trans,
         unsigned int old_size;
         int i;
 
-        slot_orig = path->slots[0];
         leaf = path->nodes[0];
 
         nritems = btrfs_header_nritems(leaf);
@@ -3787,7 +3792,6 @@ int btrfs_insert_empty_items(struct btrfs_trans_handle *trans,
                             struct btrfs_key *cpu_key, u32 *data_size,
                             int nr)
 {
-        struct extent_buffer *leaf;
         int ret = 0;
         int slot;
         int i;
@@ -3804,7 +3808,6 @@ int btrfs_insert_empty_items(struct btrfs_trans_handle *trans,
         if (ret < 0)
                 goto out;
 
-        leaf = path->nodes[0];
         slot = path->slots[0];
         BUG_ON(slot < 0);