Btrfs: properly check free space for tree balancing

btrfs_insert_empty_items takes the space needed by the btrfs_item
structure into account when calculating the required free space.

So the tree balancing code shouldn't add sizeof(struct btrfs_item)
to the size when checking the free space. This patch removes these
superfluous additions.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>

diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index f6f7a6a..7fad2e3 100644 (file)
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -1587,8 +1587,8 @@ cow_done:
                                btrfs_tree_lock(b);
                } else {
                        p->slots[level] = slot;
-                       if (ins_len > 0 && btrfs_leaf_free_space(root, b) <
-                           sizeof(struct btrfs_item) + ins_len) {
+                       if (ins_len > 0 &&
+                           btrfs_leaf_free_space(root, b) < ins_len) {
                                int sret = split_leaf(trans, root, key,
                                                      p, ins_len, ret == 0);
                                BUG_ON(sret > 0);
@@ -2231,7 +2231,7 @@ static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root
        right = read_node_slot(root, upper, slot + 1);
        btrfs_tree_lock(right);
        free_space = btrfs_leaf_free_space(root, right);
-       if (free_space < data_size + sizeof(struct btrfs_item))
+       if (free_space < data_size)
                goto out_unlock;
 
        /* cow and double check */
@@ -2241,7 +2241,7 @@ static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root
                goto out_unlock;
 
        free_space = btrfs_leaf_free_space(root, right);
-       if (free_space < data_size + sizeof(struct btrfs_item))
+       if (free_space < data_size)
                goto out_unlock;
 
        left_nritems = btrfs_header_nritems(left);
@@ -2254,7 +2254,7 @@ static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root
                nr = 1;
 
        if (path->slots[0] >= left_nritems)
-               push_space += data_size + sizeof(*item);
+               push_space += data_size;
 
        i = left_nritems - 1;
        while (i >= nr) {
@@ -2271,7 +2271,7 @@ static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root
                }
 
                if (path->slots[0] == i)
-                       push_space += data_size + sizeof(*item);
+                       push_space += data_size;
 
                if (!left->map_token) {
                        map_extent_buffer(left, (unsigned long)item,
@@ -2427,7 +2427,7 @@ static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root
        left = read_node_slot(root, path->nodes[1], slot - 1);
        btrfs_tree_lock(left);
        free_space = btrfs_leaf_free_space(root, left);
-       if (free_space < data_size + sizeof(struct btrfs_item)) {
+       if (free_space < data_size) {
                ret = 1;
                goto out;
        }
@@ -2442,7 +2442,7 @@ static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root
        }
 
        free_space = btrfs_leaf_free_space(root, left);
-       if (free_space < data_size + sizeof(struct btrfs_item)) {
+       if (free_space < data_size) {
                ret = 1;
                goto out;
        }
@@ -2473,7 +2473,7 @@ static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root
                }
 
                if (path->slots[0] == i)
-                       push_space += data_size + sizeof(*item);
+                       push_space += data_size;
 
                this_item_size = btrfs_item_size(right, item);
                if (this_item_size + sizeof(*item) + push_space > free_space)
@@ -2510,7 +2510,7 @@ static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root
                     btrfs_item_offset_nr(right, push_items - 1),
                     push_space);
        old_left_nritems = btrfs_header_nritems(left);
-       BUG_ON(old_left_nritems < 0);
+       BUG_ON(old_left_nritems <= 0);
 
        old_left_item_size = btrfs_item_offset_nr(left, old_left_nritems - 1);
        for (i = old_left_nritems; i < old_left_nritems + push_items; i++) {
@@ -2628,7 +2628,6 @@ static noinline int split_leaf(struct btrfs_trans_handle *trans,
        int mid;
        int slot;
        struct extent_buffer *right;
-       int space_needed = data_size + sizeof(struct btrfs_item);
        int data_copy_size;
        int rt_data_off;
        int i;
@@ -2638,9 +2637,6 @@ static noinline int split_leaf(struct btrfs_trans_handle *trans,
        int num_doubles = 0;
        struct btrfs_disk_key disk_key;
 
-       if (extend && data_size)
-               space_needed = data_size;
-
        /* first try to make some room by pushing left and right */
        if (data_size && ins_key->type != BTRFS_DIR_ITEM_KEY) {
                wret = push_leaf_right(trans, root, path, data_size, 0);
@@ -2655,7 +2651,7 @@ static noinline int split_leaf(struct btrfs_trans_handle *trans,
                l = path->nodes[0];
 
                /* did the pushes work? */
-               if (btrfs_leaf_free_space(root, l) >= space_needed)
+               if (btrfs_leaf_free_space(root, l) >= data_size)
                        return 0;
        }
 
@@ -2694,7 +2690,7 @@ again:
                            BTRFS_UUID_SIZE);
        if (mid <= slot) {
                if (nritems == 1 ||
-                   leaf_space_used(l, mid, nritems - mid) + space_needed >
+                   leaf_space_used(l, mid, nritems - mid) + data_size >
                        BTRFS_LEAF_DATA_SIZE(root)) {
                        if (slot >= nritems) {
                                btrfs_cpu_key_to_disk(&disk_key, ins_key);
@@ -2716,12 +2712,12 @@ again:
                        mid = slot;
                        if (mid != nritems &&
                            leaf_space_used(l, mid, nritems - mid) +
-                           space_needed > BTRFS_LEAF_DATA_SIZE(root)) {
+                           data_size > BTRFS_LEAF_DATA_SIZE(root)) {
                                double_split = 1;
                        }
                }
        } else {
-               if (leaf_space_used(l, 0, mid + 1) + space_needed >
+               if (leaf_space_used(l, 0, mid) + data_size >
                        BTRFS_LEAF_DATA_SIZE(root)) {
                        if (!extend && data_size && slot == 0) {
                                btrfs_cpu_key_to_disk(&disk_key, ins_key);
@@ -2750,7 +2746,7 @@ again:
                                mid = slot;
                                if (mid != nritems &&
                                    leaf_space_used(l, mid, nritems - mid) +
-                                   space_needed > BTRFS_LEAF_DATA_SIZE(root)) {
+                                   data_size > BTRFS_LEAF_DATA_SIZE(root)) {
                                        double_split = 1;
                                }
                        }
@@ -2883,7 +2879,8 @@ int btrfs_split_item(struct btrfs_trans_handle *trans,
                return -EAGAIN;
        }
 
-       ret = split_leaf(trans, root, &orig_key, path, 0, 0);
+       ret = split_leaf(trans, root, &orig_key, path,
+                        sizeof(struct btrfs_item), 1);
        path->keep_locks = 0;
        BUG_ON(ret);
 
@@ -3169,14 +3166,17 @@ int btrfs_insert_some_items(struct btrfs_trans_handle *trans,
        struct btrfs_disk_key disk_key;
        struct btrfs_key found_key;
 
-       found_key.objectid = 0;
-       nr = min_t(int, nr, BTRFS_NODEPTRS_PER_BLOCK(root));
-
-       for (i = 0; i < nr; i++)
+       for (i = 0; i < nr; i++) {
+               if (total_size + data_size[i] + sizeof(struct btrfs_item) >
+                   BTRFS_LEAF_DATA_SIZE(root)) {
+                       break;
+                       nr = i;
+               }
                total_data += data_size[i];
+               total_size += data_size[i] + sizeof(struct btrfs_item);
+       }
+       BUG_ON(nr == 0);
 
-       total_data = min_t(u32, total_data, BTRFS_LEAF_DATA_SIZE(root));
-       total_size = total_data + (nr * sizeof(struct btrfs_item));
        ret = btrfs_search_slot(trans, root, cpu_key, path, total_size, 1);
        if (ret == 0)
                return -EEXIST;

diff --git a/fs/btrfs/file-item.c b/fs/btrfs/file-item.c
index 7acadf3..cc6e0b6 100644 (file)
--- a/fs/btrfs/file-item.c
+++ b/fs/btrfs/file-item.c
@@ -300,6 +300,10 @@ int btrfs_lookup_csums_range(struct btrfs_root *root, u64 start, u64 end,
 
                size = btrfs_item_size_nr(leaf, path->slots[0]);
                csum_end = key.offset + (size / csum_size) * root->sectorsize;
+               if (csum_end <= start) {
+                       path->slots[0]++;
+                       continue;
+               }
 
                size = min(csum_end, end + 1) - start;
                sums = kzalloc(btrfs_ordered_sum_size(root, size), GFP_NOFS);

diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index 6ac1b7f..33eee25 100644 (file)
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -374,13 +374,8 @@ insert:
                if (found_size > item_size) {
                        btrfs_truncate_item(trans, root, path, item_size, 1);
                } else if (found_size < item_size) {
-                       ret = btrfs_del_item(trans, root,
-                                            path);
-                       BUG_ON(ret);
-
-                       btrfs_release_path(root, path);
-                       ret = btrfs_insert_empty_item(trans,
-                                 root, path, key, item_size);
+                       ret = btrfs_extend_item(trans, root, path,
+                                               item_size - found_size);
                        BUG_ON(ret);
                }
        } else if (ret) {