Btrfs: Add support for online device removal

[safe/jmp/linux-2.6] / fs / btrfs / tree-defrag.c

diff --git a/fs/btrfs/tree-defrag.c b/fs/btrfs/tree-defrag.c
index daf019a..256af18 100644 (file)
--- a/fs/btrfs/tree-defrag.c
+++ b/fs/btrfs/tree-defrag.c
@@ -27,13 +27,15 @@ static void reada_defrag(struct btrfs_root *root,
 {
        int i;
        u32 nritems;
-       u64 blocknr;
+       u64 bytenr;
+       u32 blocksize;
        int ret;
 
+       blocksize = btrfs_level_size(root, btrfs_header_level(node) - 1);
        nritems = btrfs_header_nritems(node);
        for (i = 0; i < nritems; i++) {
-               blocknr = btrfs_node_blockptr(node, i);
-               ret = readahead_tree_block(root, blocknr);
+               bytenr = btrfs_node_blockptr(node, i);
+               ret = readahead_tree_block(root, bytenr, blocksize);
                if (ret)
                        break;
        }
@@ -46,7 +48,7 @@ static int defrag_walk_down(struct btrfs_trans_handle *trans,
 {
        struct extent_buffer *next;
        struct extent_buffer *cur;
-       u64 blocknr;
+       u64 bytenr;
        int ret = 0;
        int is_extent = 0;
 
@@ -56,6 +58,10 @@ static int defrag_walk_down(struct btrfs_trans_handle *trans,
        if (root->fs_info->extent_root == root)
                is_extent = 1;
 
+       if (*level == 1 && cache_only && path->nodes[1] &&
+           !btrfs_buffer_defrag(path->nodes[1])) {
+               goto out;
+       }
        while(*level > 0) {
                WARN_ON(*level < 0);
                WARN_ON(*level >= BTRFS_MAX_LEVEL);
@@ -72,34 +78,37 @@ static int defrag_walk_down(struct btrfs_trans_handle *trans,
                        break;
 
                if (*level == 1) {
+                       WARN_ON(btrfs_header_generation(path->nodes[*level]) !=
+                                                       trans->transid);
                        ret = btrfs_realloc_node(trans, root,
                                                 path->nodes[*level],
-                                                cache_only, last_ret);
+                                                path->slots[*level],
+                                                cache_only, last_ret,
+                                                &root->defrag_progress);
                        if (is_extent)
                                btrfs_extent_post_op(trans, root);
 
                        break;
                }
-               blocknr = btrfs_node_blockptr(cur, path->slots[*level]);
+               bytenr = btrfs_node_blockptr(cur, path->slots[*level]);
 
                if (cache_only) {
-                       next = btrfs_find_tree_block(root, blocknr);
-                       /* FIXME, test for defrag */
-                       if (!next || !btrfs_buffer_uptodate(next)) {
+                       next = btrfs_find_tree_block(root, bytenr,
+                                          btrfs_level_size(root, *level - 1));
+                       if (!next || !btrfs_buffer_uptodate(next) ||
+                           !btrfs_buffer_defrag(next)) {
                                free_extent_buffer(next);
                                path->slots[*level]++;
                                continue;
                        }
+                       btrfs_verify_block_csum(root, next);
                } else {
-                       next = read_tree_block(root, blocknr);
+                       next = read_tree_block(root, bytenr,
+                                      btrfs_level_size(root, *level - 1));
                }
                ret = btrfs_cow_block(trans, root, next, path->nodes[*level],
                                      path->slots[*level], &next);
                BUG_ON(ret);
-               ret = btrfs_realloc_node(trans, root, next, cache_only,
-                                        last_ret);
-               BUG_ON(ret);
-
                if (is_extent)
                        btrfs_extent_post_op(trans, root);
 
@@ -112,15 +121,14 @@ static int defrag_walk_down(struct btrfs_trans_handle *trans,
        }
        WARN_ON(*level < 0);
        WARN_ON(*level >= BTRFS_MAX_LEVEL);
-#if 0
-       clear_buffer_defrag(path->nodes[*level]);
-       clear_buffer_defrag_done(path->nodes[*level]);
-#endif
+
+       btrfs_clear_buffer_defrag(path->nodes[*level]);
+out:
        free_extent_buffer(path->nodes[*level]);
        path->nodes[*level] = NULL;
        *level += 1;
-       WARN_ON(ret);
-       return 0;
+       WARN_ON(ret && ret != -EAGAIN);
+       return ret;
 }
 
 static int defrag_walk_up(struct btrfs_trans_handle *trans,
@@ -144,10 +152,7 @@ static int defrag_walk_up(struct btrfs_trans_handle *trans,
                        root->defrag_level = i;
                        return 0;
                } else {
-                       /*
-                       clear_buffer_defrag(path->nodes[*level]);
-                       clear_buffer_defrag_done(path->nodes[*level]);
-                       */
+                       btrfs_clear_buffer_defrag(path->nodes[*level]);
                        free_extent_buffer(path->nodes[*level]);
                        path->nodes[*level] = NULL;
                        *level = i + 1;
@@ -175,12 +180,16 @@ int btrfs_defrag_leaves(struct btrfs_trans_handle *trans,
        if (root->ref_cows == 0 && !is_extent)
                goto out;
 
+       if (btrfs_test_opt(root, SSD))
+               goto out;
+
        path = btrfs_alloc_path();
        if (!path)
                return -ENOMEM;
 
        level = btrfs_header_level(root->node);
        orig_level = level;
+
        if (level == 0) {
                goto out;
        }
@@ -188,9 +197,6 @@ int btrfs_defrag_leaves(struct btrfs_trans_handle *trans,
                extent_buffer_get(root->node);
                ret = btrfs_cow_block(trans, root, root->node, NULL, 0, &tmp);
                BUG_ON(ret);
-               ret = btrfs_realloc_node(trans, root, root->node, cache_only,
-                                        &last_ret);
-               BUG_ON(ret);
                path->nodes[level] = root->node;
                path->slots[level] = 0;
                if (is_extent)
@@ -231,13 +237,14 @@ int btrfs_defrag_leaves(struct btrfs_trans_handle *trans,
                        break;
                if (wret < 0)
                        ret = wret;
-               ret = -EAGAIN;
+               else
+                       ret = -EAGAIN;
                break;
        }
        for (i = 0; i <= orig_level; i++) {
                if (path->nodes[i]) {
                        free_extent_buffer(path->nodes[i]);
-                       path->nodes[i] = 0;
+                       path->nodes[i] = NULL;
                }
        }
 out: