Btrfs: Add run time btree defrag, and an ioctl to force btree defrag

[linux-2.6-block.git] / fs / btrfs / extent-tree.c

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 5d4d5d8db8efa3f7cc3a9e23bc98affee85aa215..26b8d340649128d232ab3ba41e7a2f76a0905a79 100644 (file)
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -23,7 +23,8 @@
 #include "transaction.h"
 
 static int find_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root
-                           *orig_root, u64 num_blocks, u64 search_start,
+                           *orig_root, u64 num_blocks, u64 empty_size,
+                           u64 search_start,
                            u64 search_end, u64 hint_block,
                            struct btrfs_key *ins, u64 exclude_start,
                            u64 exclude_nr, int data);
@@ -379,7 +380,7 @@ int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
        path = btrfs_alloc_path();
        if (!path)
                return -ENOMEM;
-       ret = find_free_extent(trans, root->fs_info->extent_root, 0, 0,
+       ret = find_free_extent(trans, root->fs_info->extent_root, 0, 0, 0,
                               (u64)-1, 0, &ins, 0, 0, 0);
        if (ret) {
                btrfs_free_path(path);
@@ -533,7 +534,7 @@ static int write_one_cache_group(struct btrfs_trans_handle *trans,
        struct btrfs_block_group_item *bi;
        struct btrfs_key ins;
 
-       ret = find_free_extent(trans, extent_root, 0, 0, (u64)-1, 0, &ins,
+       ret = find_free_extent(trans, extent_root, 0, 0, 0, (u64)-1, 0, &ins,
                               0, 0, 0);
        /* FIXME, set bit to recalc cache groups on next mount */
        if (ret)
@@ -708,6 +709,7 @@ static int update_block_group(struct btrfs_trans_handle *trans,
 static int try_remove_page(struct address_space *mapping, unsigned long index)
 {
        int ret;
+       return 0;
        ret = invalidate_mapping_pages(mapping, index, index);
        return ret;
 }
@@ -866,7 +868,7 @@ static int __free_extent(struct btrfs_trans_handle *trans, struct btrfs_root
        if (!path)
                return -ENOMEM;
 
-       ret = find_free_extent(trans, root, 0, 0, (u64)-1, 0, &ins, 0, 0, 0);
+       ret = find_free_extent(trans, root, 0, 0, 0, (u64)-1, 0, &ins, 0, 0, 0);
        if (ret) {
                btrfs_free_path(path);
                return ret;
@@ -983,8 +985,8 @@ int btrfs_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root
  * Any available blocks before search_start are skipped.
  */
 static int find_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root
-                           *orig_root, u64 num_blocks, u64 search_start, u64
-                           search_end, u64 hint_block,
+                           *orig_root, u64 num_blocks, u64 empty_size,
+                           u64 search_start, u64 search_end, u64 hint_block,
                            struct btrfs_key *ins, u64 exclude_start,
                            u64 exclude_nr, int data)
 {
@@ -1042,6 +1044,7 @@ static int find_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root
                                                     data, 1);
        }
 
+       total_needed += empty_size;
        path = btrfs_alloc_path();
 
 check_failed:
@@ -1157,9 +1160,11 @@ check_pending:
                        goto error;
                }
                search_start = orig_search_start;
-               if (wrapped)
+               if (wrapped) {
+                       if (!full_scan)
+                               total_needed -= empty_size;
                        full_scan = 1;
-               else
+               } else
                        wrapped = 1;
                goto new_group;
        }
@@ -1238,9 +1243,11 @@ new_group:
                        ret = -ENOSPC;
                        goto error;
                }
-               if (wrapped)
+               if (wrapped) {
+                       if (!full_scan)
+                               total_needed -= empty_size;
                        full_scan = 1;
-               else
+               } else
                        wrapped = 1;
        }
        block_group = btrfs_lookup_block_group(info, search_start);
@@ -1264,7 +1271,7 @@ error:
  */
 int btrfs_alloc_extent(struct btrfs_trans_handle *trans,
                       struct btrfs_root *root, u64 owner,
-                      u64 num_blocks, u64 hint_block,
+                      u64 num_blocks, u64 empty_size, u64 hint_block,
                       u64 search_end, struct btrfs_key *ins, int data)
 {
        int ret;
@@ -1303,7 +1310,7 @@ int btrfs_alloc_extent(struct btrfs_trans_handle *trans,
         * in the correct block group.
         */
        if (data) {
-               ret = find_free_extent(trans, root, 0, 0,
+               ret = find_free_extent(trans, root, 0, 0, 0,
                                       search_end, 0, &prealloc_key, 0, 0, 0);
                BUG_ON(ret);
                if (ret)
@@ -1313,8 +1320,8 @@ int btrfs_alloc_extent(struct btrfs_trans_handle *trans,
        }
 
        /* do the real allocation */
-       ret = find_free_extent(trans, root, num_blocks, search_start,
-                              search_end, hint_block, ins,
+       ret = find_free_extent(trans, root, num_blocks, empty_size,
+                              search_start, search_end, hint_block, ins,
                               exclude_start, exclude_nr, data);
        BUG_ON(ret);
        if (ret)
@@ -1333,7 +1340,7 @@ int btrfs_alloc_extent(struct btrfs_trans_handle *trans,
                exclude_start = ins->objectid;
                exclude_nr = ins->offset;
                hint_block = exclude_start + exclude_nr;
-               ret = find_free_extent(trans, root, 0, search_start,
+               ret = find_free_extent(trans, root, 0, 0, search_start,
                                       search_end, hint_block,
                                       &prealloc_key, exclude_start,
                                       exclude_nr, 0);
@@ -1368,14 +1375,16 @@ int btrfs_alloc_extent(struct btrfs_trans_handle *trans,
  * returns the tree buffer or NULL.
  */
 struct buffer_head *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
-                                          struct btrfs_root *root, u64 hint)
+                                          struct btrfs_root *root, u64 hint,
+                                          u64 empty_size)
 {
        struct btrfs_key ins;
        int ret;
        struct buffer_head *buf;
 
        ret = btrfs_alloc_extent(trans, root, root->root_key.objectid,
-                                1, hint, (unsigned long)-1, &ins, 0);
+                                1, empty_size, hint,
+                                (unsigned long)-1, &ins, 0);
        if (ret) {
                BUG_ON(ret > 0);
                return ERR_PTR(ret);
@@ -1385,6 +1394,7 @@ struct buffer_head *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
                btrfs_free_extent(trans, root, ins.objectid, 1, 0);
                return ERR_PTR(-ENOMEM);
        }
+       WARN_ON(buffer_dirty(buf));
        set_buffer_uptodate(buf);
        set_buffer_checked(buf);
        set_radix_bit(&trans->transaction->dirty_pages, buf->b_page->index);
@@ -1591,13 +1601,15 @@ int btrfs_drop_snapshot(struct btrfs_trans_handle *trans, struct btrfs_root
                struct btrfs_key key;
                struct btrfs_disk_key *found_key;
                struct btrfs_node *node;
+
                btrfs_disk_key_to_cpu(&key, &root_item->drop_progress);
+               level = root_item->drop_level;
+               path->lowest_level = level;
                wret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
-               if (ret < 0) {
+               if (wret < 0) {
                        ret = wret;
                        goto out;
                }
-               level = root_item->drop_level;
                node = btrfs_buffer_node(path->nodes[level]);
                found_key = &node->ptrs[path->slots[level]].key;
                WARN_ON(memcmp(found_key, &root_item->drop_progress,
@@ -1617,8 +1629,6 @@ int btrfs_drop_snapshot(struct btrfs_trans_handle *trans, struct btrfs_root
                        ret = wret;
                num_walks++;
                if (num_walks > 10) {
-                       struct btrfs_key key;
-                       btrfs_disk_key_to_cpu(&key, &root_item->drop_progress);
                        ret = -EAGAIN;
                        get_bh(root->node);
                        break;
@@ -1627,6 +1637,7 @@ int btrfs_drop_snapshot(struct btrfs_trans_handle *trans, struct btrfs_root
        for (i = 0; i <= orig_level; i++) {
                if (path->nodes[i]) {
                        btrfs_block_release(root, path->nodes[i]);
+                       path->nodes[i] = 0;
                }
        }
 out: