+ while(total) {
+ cache = btrfs_lookup_block_group(info, bytenr);
+ if (!cache) {
+ return -1;
+ }
+ byte_in_group = bytenr - cache->key.objectid;
+ WARN_ON(byte_in_group > cache->key.offset);
+ start = cache->key.objectid;
+ end = start + cache->key.offset - 1;
+ set_extent_bits(&info->block_group_cache, start, end,
+ BLOCK_GROUP_DIRTY, GFP_NOFS);
+
+ old_val = btrfs_block_group_used(&cache->item);
+ num_bytes = min(total, cache->key.offset - byte_in_group);
+
+ if (alloc) {
+ old_val += num_bytes;
+ cache->space_info->bytes_used += num_bytes;
+ } else {
+ old_val -= num_bytes;
+ cache->space_info->bytes_used -= num_bytes;
+ if (mark_free) {
+ set_extent_dirty(&info->free_space_cache,
+ bytenr, bytenr + num_bytes - 1,
+ GFP_NOFS);
+ }
+ }
+ btrfs_set_block_group_used(&cache->item, old_val);
+ total -= num_bytes;
+ bytenr += num_bytes;
+ }
+ return 0;
+}
+
+static int update_pinned_extents(struct btrfs_root *root,
+ u64 bytenr, u64 num, int pin)
+{
+ u64 len;
+ struct btrfs_block_group_cache *cache;
+ struct btrfs_fs_info *fs_info = root->fs_info;
+
+ if (pin) {
+ set_extent_dirty(&fs_info->pinned_extents,
+ bytenr, bytenr + num - 1, GFP_NOFS);
+ } else {
+ clear_extent_dirty(&fs_info->pinned_extents,
+ bytenr, bytenr + num - 1, GFP_NOFS);
+ }
+ while (num > 0) {
+ cache = btrfs_lookup_block_group(fs_info, bytenr);
+ if (!cache) {
+ len = min((u64)root->sectorsize, num);
+ goto next;
+ }
+ WARN_ON(!cache);
+ len = min(num, cache->key.offset -
+ (bytenr - cache->key.objectid));
+ if (pin) {
+ cache->pinned += len;
+ cache->space_info->bytes_pinned += len;
+ fs_info->total_pinned += len;
+ } else {
+ cache->pinned -= len;
+ cache->space_info->bytes_pinned -= len;
+ fs_info->total_pinned -= len;
+ }
+next:
+ bytenr += len;
+ num -= len;
+ }
+ return 0;
+}
+
+int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct extent_io_tree *unpin)
+{
+ u64 start;
+ u64 end;
+ int ret;
+ struct extent_io_tree *free_space_cache;
+ free_space_cache = &root->fs_info->free_space_cache;
+
+ while(1) {
+ ret = find_first_extent_bit(unpin, 0, &start, &end,
+ EXTENT_DIRTY);
+ if (ret)
+ break;
+ update_pinned_extents(root, start, end + 1 - start, 0);
+ clear_extent_dirty(unpin, start, end, GFP_NOFS);
+ set_extent_dirty(free_space_cache, start, end, GFP_NOFS);
+ }
+ return 0;
+}
+
+static int extent_root_pending_ops(struct btrfs_fs_info *info)
+{
+ u64 start;
+ u64 end;
+ int ret;
+
+ ret = find_first_extent_bit(&info->extent_ins, 0, &start,
+ &end, EXTENT_LOCKED);
+ if (!ret) {
+ ret = find_first_extent_bit(&info->pending_del, 0, &start, &end,
+ EXTENT_LOCKED);
+ }
+ return ret == 0;
+
+}
+static int finish_current_insert(struct btrfs_trans_handle *trans,
+ struct btrfs_root *extent_root)
+{
+ u64 start;
+ u64 end;
+ u64 priv;
+ struct btrfs_fs_info *info = extent_root->fs_info;
+ struct pending_extent_op *extent_op;
+ struct btrfs_key key;
+ int ret;
+ int skinny_metadata =
+ btrfs_fs_incompat(extent_root->fs_info,
+ BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA);
+
+ while(1) {
+ ret = find_first_extent_bit(&info->extent_ins, 0, &start,
+ &end, EXTENT_LOCKED);
+ if (ret)
+ break;
+
+ ret = get_state_private(&info->extent_ins, start, &priv);
+ BUG_ON(ret);
+ extent_op = (struct pending_extent_op *)(unsigned long)priv;
+
+ if (extent_op->type == PENDING_EXTENT_INSERT) {
+ key.objectid = start;
+ if (skinny_metadata) {
+ key.offset = extent_op->level;
+ key.type = BTRFS_METADATA_ITEM_KEY;
+ } else {
+ key.offset = extent_op->num_bytes;
+ key.type = BTRFS_EXTENT_ITEM_KEY;
+ }
+ ret = alloc_reserved_tree_block(trans, extent_root,
+ extent_root->root_key.objectid,
+ trans->transid,
+ extent_op->flags,
+ &extent_op->key,
+ extent_op->level, &key);
+ BUG_ON(ret);
+ } else {
+ BUG_ON(1);
+ }
+
+ clear_extent_bits(&info->extent_ins, start, end, EXTENT_LOCKED,
+ GFP_NOFS);
+ kfree(extent_op);
+ }
+ return 0;
+}
+
+static int pin_down_bytes(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ u64 bytenr, u64 num_bytes, int is_data)
+{
+ int err = 0;
+ struct extent_buffer *buf;
+
+ if (is_data)
+ goto pinit;
+
+ buf = btrfs_find_tree_block(root, bytenr, num_bytes);
+ if (!buf)
+ goto pinit;
+
+ /* we can reuse a block if it hasn't been written
+ * and it is from this transaction. We can't
+ * reuse anything from the tree log root because
+ * it has tiny sub-transactions.
+ */
+ if (btrfs_buffer_uptodate(buf, 0)) {
+ u64 header_owner = btrfs_header_owner(buf);
+ u64 header_transid = btrfs_header_generation(buf);
+ if (header_owner != BTRFS_TREE_LOG_OBJECTID &&
+ header_transid == trans->transid &&
+ !btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) {
+ clean_tree_block(NULL, root, buf);
+ free_extent_buffer(buf);
+ return 1;
+ }
+ }
+ free_extent_buffer(buf);
+pinit:
+ update_pinned_extents(root, bytenr, num_bytes, 1);
+
+ BUG_ON(err < 0);
+ return 0;
+}
+
+void btrfs_pin_extent(struct btrfs_fs_info *fs_info,
+ u64 bytenr, u64 num_bytes)
+{
+ update_pinned_extents(fs_info->extent_root, bytenr, num_bytes, 1);
+}
+
+void btrfs_unpin_extent(struct btrfs_fs_info *fs_info,
+ u64 bytenr, u64 num_bytes)
+{
+ update_pinned_extents(fs_info->extent_root, bytenr, num_bytes, 0);
+}
+
+/*
+ * remove an extent from the root, returns 0 on success
+ */
+static int __free_extent(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ u64 bytenr, u64 num_bytes, u64 parent,
+ u64 root_objectid, u64 owner_objectid,
+ u64 owner_offset, int refs_to_drop)
+{
+
+ struct btrfs_key key;
+ struct btrfs_path *path;
+ struct btrfs_root *extent_root = root->fs_info->extent_root;
+ struct extent_buffer *leaf;
+ struct btrfs_extent_item *ei;
+ struct btrfs_extent_inline_ref *iref;
+ int ret;
+ int is_data;
+ int extent_slot = 0;
+ int found_extent = 0;
+ int num_to_del = 1;
+ u32 item_size;
+ u64 refs;
+ int skinny_metadata =
+ btrfs_fs_incompat(extent_root->fs_info,
+ BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA);
+
+ if (root->fs_info->free_extent_hook) {
+ root->fs_info->free_extent_hook(trans, root, bytenr, num_bytes,
+ parent, root_objectid, owner_objectid,
+ owner_offset, refs_to_drop);
+
+ }
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ path->reada = 1;
+
+ is_data = owner_objectid >= BTRFS_FIRST_FREE_OBJECTID;
+ if (is_data)
+ skinny_metadata = 0;
+ BUG_ON(!is_data && refs_to_drop != 1);
+
+ ret = lookup_extent_backref(trans, extent_root, path, &iref,
+ bytenr, num_bytes, parent,
+ root_objectid, owner_objectid,
+ owner_offset);
+ if (ret == 0) {
+ extent_slot = path->slots[0];
+ while (extent_slot >= 0) {
+ btrfs_item_key_to_cpu(path->nodes[0], &key,
+ extent_slot);
+ if (key.objectid != bytenr)
+ break;
+ if (key.type == BTRFS_EXTENT_ITEM_KEY &&
+ key.offset == num_bytes) {
+ found_extent = 1;
+ break;
+ }
+ if (key.type == BTRFS_METADATA_ITEM_KEY &&
+ key.offset == owner_objectid) {
+ found_extent = 1;
+ break;
+ }
+ if (path->slots[0] - extent_slot > 5)
+ break;
+ extent_slot--;
+ }
+#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
+ item_size = btrfs_item_size_nr(path->nodes[0], extent_slot);
+ if (found_extent && item_size < sizeof(*ei))
+ found_extent = 0;
+#endif
+ if (!found_extent) {
+ BUG_ON(iref);
+ ret = remove_extent_backref(trans, extent_root, path,
+ NULL, refs_to_drop,
+ is_data);
+ BUG_ON(ret);
+ btrfs_release_path(path);
+
+ key.objectid = bytenr;
+
+ if (skinny_metadata) {
+ key.type = BTRFS_METADATA_ITEM_KEY;
+ key.offset = owner_objectid;
+ } else {
+ key.type = BTRFS_EXTENT_ITEM_KEY;
+ key.offset = num_bytes;
+ }
+
+ ret = btrfs_search_slot(trans, extent_root,
+ &key, path, -1, 1);
+ if (ret > 0 && skinny_metadata && path->slots[0]) {
+ path->slots[0]--;
+ btrfs_item_key_to_cpu(path->nodes[0],
+ &key,
+ path->slots[0]);
+ if (key.objectid == bytenr &&
+ key.type == BTRFS_EXTENT_ITEM_KEY &&
+ key.offset == num_bytes)
+ ret = 0;
+ }
+
+ if (ret > 0 && skinny_metadata) {
+ skinny_metadata = 0;
+ btrfs_release_path(path);
+ key.type = BTRFS_EXTENT_ITEM_KEY;
+ key.offset = num_bytes;
+ ret = btrfs_search_slot(trans, extent_root,
+ &key, path, -1, 1);
+ }
+
+ if (ret) {
+ printk(KERN_ERR "umm, got %d back from search"
+ ", was looking for %llu\n", ret,
+ (unsigned long long)bytenr);
+ btrfs_print_leaf(extent_root, path->nodes[0]);
+ }
+ BUG_ON(ret);
+ extent_slot = path->slots[0];
+ }
+ } else {
+ printk(KERN_ERR "btrfs unable to find ref byte nr %llu "
+ "parent %llu root %llu owner %llu offset %llu\n",
+ (unsigned long long)bytenr,
+ (unsigned long long)parent,
+ (unsigned long long)root_objectid,
+ (unsigned long long)owner_objectid,
+ (unsigned long long)owner_offset);
+ ret = -EIO;
+ goto fail;
+ }
+
+ leaf = path->nodes[0];
+ item_size = btrfs_item_size_nr(leaf, extent_slot);
+#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
+ if (item_size < sizeof(*ei)) {
+ BUG_ON(found_extent || extent_slot != path->slots[0]);
+ ret = convert_extent_item_v0(trans, extent_root, path,
+ owner_objectid, 0);
+ BUG_ON(ret < 0);
+
+ btrfs_release_path(path);
+
+ key.objectid = bytenr;
+ key.type = BTRFS_EXTENT_ITEM_KEY;
+ key.offset = num_bytes;
+
+ ret = btrfs_search_slot(trans, extent_root, &key, path,
+ -1, 1);
+ if (ret) {
+ printk(KERN_ERR "umm, got %d back from search"
+ ", was looking for %llu\n", ret,
+ (unsigned long long)bytenr);
+ btrfs_print_leaf(extent_root, path->nodes[0]);
+ }
+ BUG_ON(ret);
+ extent_slot = path->slots[0];
+ leaf = path->nodes[0];
+ item_size = btrfs_item_size_nr(leaf, extent_slot);
+ }
+#endif
+ BUG_ON(item_size < sizeof(*ei));
+ ei = btrfs_item_ptr(leaf, extent_slot,
+ struct btrfs_extent_item);
+ if (owner_objectid < BTRFS_FIRST_FREE_OBJECTID &&
+ key.type == BTRFS_EXTENT_ITEM_KEY) {
+ struct btrfs_tree_block_info *bi;
+ BUG_ON(item_size < sizeof(*ei) + sizeof(*bi));
+ bi = (struct btrfs_tree_block_info *)(ei + 1);
+ WARN_ON(owner_objectid != btrfs_tree_block_level(leaf, bi));
+ }
+
+ refs = btrfs_extent_refs(leaf, ei);
+ BUG_ON(refs < refs_to_drop);
+ refs -= refs_to_drop;
+
+ if (refs > 0) {
+ /*
+ * In the case of inline back ref, reference count will
+ * be updated by remove_extent_backref
+ */
+ if (iref) {
+ BUG_ON(!found_extent);
+ } else {
+ btrfs_set_extent_refs(leaf, ei, refs);
+ btrfs_mark_buffer_dirty(leaf);
+ }
+ if (found_extent) {
+ ret = remove_extent_backref(trans, extent_root, path,
+ iref, refs_to_drop,
+ is_data);
+ BUG_ON(ret);
+ }
+ } else {
+ int mark_free = 0;
+ int pin = 1;
+
+ if (found_extent) {
+ BUG_ON(is_data && refs_to_drop !=
+ extent_data_ref_count(root, path, iref));
+ if (iref) {
+ BUG_ON(path->slots[0] != extent_slot);
+ } else {
+ BUG_ON(path->slots[0] != extent_slot + 1);
+ path->slots[0] = extent_slot;
+ num_to_del = 2;
+ }
+ }
+
+ if (pin) {
+ ret = pin_down_bytes(trans, root, bytenr, num_bytes,
+ is_data);
+ if (ret > 0)
+ mark_free = 1;
+ BUG_ON(ret < 0);
+ }
+
+ ret = btrfs_del_items(trans, extent_root, path, path->slots[0],
+ num_to_del);
+ BUG_ON(ret);
+ btrfs_release_path(path);
+
+ if (is_data) {
+ ret = btrfs_del_csums(trans, root, bytenr, num_bytes);
+ BUG_ON(ret);
+ }
+
+ update_block_group(trans, root, bytenr, num_bytes, 0, mark_free);
+ }
+fail:
+ btrfs_free_path(path);
+ finish_current_insert(trans, extent_root);
+ return ret;
+}
+
+/*
+ * find all the blocks marked as pending in the radix tree and remove
+ * them from the extent map
+ */
+static int del_pending_extents(struct btrfs_trans_handle *trans, struct
+ btrfs_root *extent_root)
+{
+ int ret;
+ int err = 0;
+ u64 start;
+ u64 end;
+ u64 priv;
+ struct extent_io_tree *pending_del;
+ struct extent_io_tree *extent_ins;
+ struct pending_extent_op *extent_op;
+
+ extent_ins = &extent_root->fs_info->extent_ins;
+ pending_del = &extent_root->fs_info->pending_del;
+
+ while(1) {
+ ret = find_first_extent_bit(pending_del, 0, &start, &end,
+ EXTENT_LOCKED);
+ if (ret)
+ break;
+
+ ret = get_state_private(pending_del, start, &priv);
+ BUG_ON(ret);
+ extent_op = (struct pending_extent_op *)(unsigned long)priv;
+
+ clear_extent_bits(pending_del, start, end, EXTENT_LOCKED,
+ GFP_NOFS);
+
+ if (!test_range_bit(extent_ins, start, end,
+ EXTENT_LOCKED, 0)) {
+ ret = __free_extent(trans, extent_root,
+ start, end + 1 - start, 0,
+ extent_root->root_key.objectid,
+ extent_op->level, 0, 1);
+ kfree(extent_op);
+ } else {
+ kfree(extent_op);
+ ret = get_state_private(extent_ins, start, &priv);
+ BUG_ON(ret);
+ extent_op = (struct pending_extent_op *)
+ (unsigned long)priv;
+
+ clear_extent_bits(extent_ins, start, end,
+ EXTENT_LOCKED, GFP_NOFS);
+
+ if (extent_op->type == PENDING_BACKREF_UPDATE)
+ BUG_ON(1);
+
+ kfree(extent_op);
+ }
+ if (ret)
+ err = ret;
+ }
+ return err;
+}
+
+
+int btrfs_free_tree_block(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct extent_buffer *buf,
+ u64 parent, int last_ref)
+{
+ return btrfs_free_extent(trans, root, buf->start, buf->len, parent,
+ root->root_key.objectid,
+ btrfs_header_level(buf), 0);
+}
+
+/*
+ * remove an extent from the root, returns 0 on success
+ */
+
+int btrfs_free_extent(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ u64 bytenr, u64 num_bytes, u64 parent,
+ u64 root_objectid, u64 owner, u64 offset)
+{
+ struct btrfs_root *extent_root = root->fs_info->extent_root;
+ int pending_ret;
+ int ret;
+
+ WARN_ON(num_bytes < root->sectorsize);
+ if (root == extent_root) {
+ struct pending_extent_op *extent_op;
+
+ extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS);
+ BUG_ON(!extent_op);
+
+ extent_op->type = PENDING_EXTENT_DELETE;
+ extent_op->bytenr = bytenr;
+ extent_op->num_bytes = num_bytes;
+ extent_op->level = (int)owner;
+
+ set_extent_bits(&root->fs_info->pending_del,
+ bytenr, bytenr + num_bytes - 1,
+ EXTENT_LOCKED, GFP_NOFS);
+ set_state_private(&root->fs_info->pending_del,
+ bytenr, (unsigned long)extent_op);
+ return 0;
+ }
+ ret = __free_extent(trans, root, bytenr, num_bytes, parent,
+ root_objectid, owner, offset, 1);
+ pending_ret = del_pending_extents(trans, root->fs_info->extent_root);
+ return ret ? ret : pending_ret;
+}
+
+static u64 stripe_align(struct btrfs_root *root, u64 val)
+{
+ u64 mask = ((u64)root->stripesize - 1);
+ u64 ret = (val + mask) & ~mask;
+ return ret;
+}
+
+/*
+ * walks the btree of allocated extents and find a hole of a given size.
+ * The key ins is changed to record the hole:
+ * ins->objectid == block start
+ * ins->flags = BTRFS_EXTENT_ITEM_KEY
+ * ins->offset == number of blocks
+ * Any available blocks before search_start are skipped.
+ */
+static int noinline find_free_extent(struct btrfs_trans_handle *trans,
+ struct btrfs_root *orig_root,
+ u64 num_bytes, u64 empty_size,
+ u64 search_start, u64 search_end,
+ u64 hint_byte, struct btrfs_key *ins,
+ u64 exclude_start, u64 exclude_nr,
+ int data)
+{
+ int ret;
+ u64 orig_search_start = search_start;
+ struct btrfs_root * root = orig_root->fs_info->extent_root;
+ struct btrfs_fs_info *info = root->fs_info;
+ u64 total_needed = num_bytes;
+ struct btrfs_block_group_cache *block_group;
+ int full_scan = 0;
+ int wrapped = 0;
+
+ WARN_ON(num_bytes < root->sectorsize);
+ ins->type = BTRFS_EXTENT_ITEM_KEY;
+
+ search_start = stripe_align(root, search_start);
+
+ if (hint_byte) {
+ block_group = btrfs_lookup_first_block_group(info, hint_byte);
+ if (!block_group)
+ hint_byte = search_start;
+ block_group = btrfs_find_block_group(root, block_group,
+ hint_byte, data, 1);
+ } else {
+ block_group = btrfs_find_block_group(root,
+ trans->block_group,
+ search_start, data, 1);
+ }
+
+ total_needed += empty_size;
+
+check_failed:
+ search_start = stripe_align(root, search_start);
+ if (!block_group) {
+ block_group = btrfs_lookup_first_block_group(info,
+ search_start);
+ if (!block_group)
+ block_group = btrfs_lookup_first_block_group(info,
+ orig_search_start);
+ }
+ ret = find_search_start(root, &block_group, &search_start,
+ total_needed, data);
+ if (ret)
+ goto new_group;
+
+ ins->objectid = search_start;
+ ins->offset = num_bytes;
+
+ if (ins->objectid + num_bytes >
+ block_group->key.objectid + block_group->key.offset) {
+ search_start = block_group->key.objectid +
+ block_group->key.offset;
+ goto new_group;
+ }
+
+ if (test_range_bit(&info->extent_ins, ins->objectid,
+ ins->objectid + num_bytes -1, EXTENT_LOCKED, 0)) {
+ search_start = ins->objectid + num_bytes;
+ goto new_group;
+ }
+
+ if (test_range_bit(&info->pinned_extents, ins->objectid,
+ ins->objectid + num_bytes -1, EXTENT_DIRTY, 0)) {
+ search_start = ins->objectid + num_bytes;
+ goto new_group;
+ }
+
+ if (info->excluded_extents &&
+ test_range_bit(info->excluded_extents, ins->objectid,
+ ins->objectid + num_bytes -1, EXTENT_DIRTY, 0)) {
+ search_start = ins->objectid + num_bytes;
+ goto new_group;
+ }
+
+ if (exclude_nr > 0 && (ins->objectid + num_bytes > exclude_start &&
+ ins->objectid < exclude_start + exclude_nr)) {
+ search_start = exclude_start + exclude_nr;
+ goto new_group;
+ }
+
+ if (!(data & BTRFS_BLOCK_GROUP_DATA)) {
+ if (check_crossing_stripes(info, ins->objectid, num_bytes)) {
+ struct btrfs_block_group_cache *bg_cache;
+ u64 bg_offset;
+
+ bg_cache = btrfs_lookup_block_group(info, ins->objectid);
+ if (!bg_cache)
+ goto no_bg_cache;
+ bg_offset = ins->objectid - bg_cache->key.objectid;
+
+ search_start = round_up(bg_offset + num_bytes,
+ BTRFS_STRIPE_LEN) + bg_offset;
+ goto new_group;
+ }
+no_bg_cache:
+ block_group = btrfs_lookup_block_group(info, ins->objectid);
+ if (block_group)
+ trans->block_group = block_group;
+ }