btrfs: root->fs_info cleanup, add fs_info convenience variables

In routines where someptr->fs_info is referenced multiple times, we
introduce a convenience variable.  This makes the code considerably
more readable.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

1 files changed, 393 insertions, 358 deletions

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 2e395d46ba9c..03512c6f4964 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -226,10 +226,11 @@ block_group_cache_tree_search(struct btrfs_fs_info *info, u64 bytenr,
 static int add_excluded_extent(struct btrfs_root *root,
 			       u64 start, u64 num_bytes)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	u64 end = start + num_bytes - 1;
-	set_extent_bits(&root->fs_info->freed_extents[0],
+	set_extent_bits(&fs_info->freed_extents[0],
 			start, end, EXTENT_UPTODATE);
-	set_extent_bits(&root->fs_info->freed_extents[1],
+	set_extent_bits(&fs_info->freed_extents[1],
 			start, end, EXTENT_UPTODATE);
 	return 0;
 }
@@ -237,20 +238,22 @@ static int add_excluded_extent(struct btrfs_root *root,
 static void free_excluded_extents(struct btrfs_root *root,
 				  struct btrfs_block_group_cache *cache)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	u64 start, end;
 
 	start = cache->key.objectid;
 	end = start + cache->key.offset - 1;
 
-	clear_extent_bits(&root->fs_info->freed_extents[0],
+	clear_extent_bits(&fs_info->freed_extents[0],
 			  start, end, EXTENT_UPTODATE);
-	clear_extent_bits(&root->fs_info->freed_extents[1],
+	clear_extent_bits(&fs_info->freed_extents[1],
 			  start, end, EXTENT_UPTODATE);
 }
 
 static int exclude_super_stripes(struct btrfs_root *root,
 				 struct btrfs_block_group_cache *cache)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	u64 bytenr;
 	u64 *logical;
 	int stripe_len;
@@ -267,7 +270,7 @@ static int exclude_super_stripes(struct btrfs_root *root,
 
 	for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
 		bytenr = btrfs_sb_offset(i);
-		ret = btrfs_rmap_block(root->fs_info, cache->key.objectid,
+		ret = btrfs_rmap_block(fs_info, cache->key.objectid,
 				       bytenr, 0, &logical, &nr, &stripe_len);
 		if (ret)
 			return ret;
@@ -332,10 +335,12 @@ static void put_caching_control(struct btrfs_caching_control *ctl)
 static void fragment_free_space(struct btrfs_root *root,
 				struct btrfs_block_group_cache *block_group)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
+
 	u64 start = block_group->key.objectid;
 	u64 len = block_group->key.offset;
 	u64 chunk = block_group->flags & BTRFS_BLOCK_GROUP_METADATA ?
-		root->fs_info->nodesize : root->fs_info->sectorsize;
+		fs_info->nodesize : fs_info->sectorsize;
 	u64 step = chunk << 1;
 
 	while (len > chunk) {
@@ -394,9 +399,9 @@ u64 add_new_free_space(struct btrfs_block_group_cache *block_group,
 
 static int load_extent_tree_free(struct btrfs_caching_control *caching_ctl)
 {
-	struct btrfs_block_group_cache *block_group;
-	struct btrfs_fs_info *fs_info;
-	struct btrfs_root *extent_root;
+	struct btrfs_block_group_cache *block_group = caching_ctl->block_group;
+	struct btrfs_fs_info *fs_info = block_group->fs_info;
+	struct btrfs_root *extent_root = fs_info->extent_root;
 	struct btrfs_path *path;
 	struct extent_buffer *leaf;
 	struct btrfs_key key;
@@ -406,10 +411,6 @@ static int load_extent_tree_free(struct btrfs_caching_control *caching_ctl)
 	int ret;
 	bool wakeup = true;
 
-	block_group = caching_ctl->block_group;
-	fs_info = block_group->fs_info;
-	extent_root = fs_info->extent_root;
-
 	path = btrfs_alloc_path();
 	if (!path)
 		return -ENOMEM;
@@ -780,6 +781,7 @@ void btrfs_clear_space_info_full(struct btrfs_fs_info *info)
 /* simple helper to search for an existing data extent at a given offset */
 int btrfs_lookup_data_extent(struct btrfs_root *root, u64 start, u64 len)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	int ret;
 	struct btrfs_key key;
 	struct btrfs_path *path;
@@ -791,8 +793,7 @@ int btrfs_lookup_data_extent(struct btrfs_root *root, u64 start, u64 len)
 	key.objectid = start;
 	key.offset = len;
 	key.type = BTRFS_EXTENT_ITEM_KEY;
-	ret = btrfs_search_slot(NULL, root->fs_info->extent_root, &key, path,
-				0, 0);
+	ret = btrfs_search_slot(NULL, fs_info->extent_root, &key, path, 0, 0);
 	btrfs_free_path(path);
 	return ret;
 }
@@ -810,6 +811,7 @@ int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans,
 			     struct btrfs_root *root, u64 bytenr,
 			     u64 offset, int metadata, u64 *refs, u64 *flags)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct btrfs_delayed_ref_head *head;
 	struct btrfs_delayed_ref_root *delayed_refs;
 	struct btrfs_path *path;
@@ -825,8 +827,8 @@ int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans,
 	 * If we don't have skinny metadata, don't bother doing anything
 	 * different
 	 */
-	if (metadata && !btrfs_fs_incompat(root->fs_info, SKINNY_METADATA)) {
-		offset = root->fs_info->nodesize;
+	if (metadata && !btrfs_fs_incompat(fs_info, SKINNY_METADATA)) {
+		offset = fs_info->nodesize;
 		metadata = 0;
 	}
 
@@ -847,8 +849,7 @@ search_again:
 	else
 		key.type = BTRFS_EXTENT_ITEM_KEY;
 
-	ret = btrfs_search_slot(trans, root->fs_info->extent_root,
-				&key, path, 0, 0);
+	ret = btrfs_search_slot(trans, fs_info->extent_root, &key, path, 0, 0);
 	if (ret < 0)
 		goto out_free;
 
@@ -859,7 +860,7 @@ search_again:
 					      path->slots[0]);
 			if (key.objectid == bytenr &&
 			    key.type == BTRFS_EXTENT_ITEM_KEY &&
-			    key.offset == root->fs_info->nodesize)
+			    key.offset == fs_info->nodesize)
 				ret = 0;
 		}
 	}
@@ -1540,6 +1541,7 @@ int lookup_inline_extent_backref(struct btrfs_trans_handle *trans,
 				 u64 parent, u64 root_objectid,
 				 u64 owner, u64 offset, int insert)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct btrfs_key key;
 	struct extent_buffer *leaf;
 	struct btrfs_extent_item *ei;
@@ -1553,8 +1555,7 @@ int lookup_inline_extent_backref(struct btrfs_trans_handle *trans,
 	int want;
 	int ret;
 	int err = 0;
-	bool skinny_metadata = btrfs_fs_incompat(root->fs_info,
-						 SKINNY_METADATA);
+	bool skinny_metadata = btrfs_fs_incompat(fs_info, SKINNY_METADATA);
 
 	key.objectid = bytenr;
 	key.type = BTRFS_EXTENT_ITEM_KEY;
@@ -2025,6 +2026,7 @@ static int btrfs_issue_discard(struct block_device *bdev, u64 start, u64 len,
 int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr,
 			 u64 num_bytes, u64 *actual_bytes)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	int ret;
 	u64 discarded_bytes = 0;
 	struct btrfs_bio *bbio = NULL;
@@ -2034,10 +2036,10 @@ int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr,
 	 * Avoid races with device replace and make sure our bbio has devices
 	 * associated to its stripes that don't go away while we are discarding.
 	 */
-	btrfs_bio_counter_inc_blocked(root->fs_info);
+	btrfs_bio_counter_inc_blocked(fs_info);
 	/* Tell the block device(s) that the sectors can be discarded */
-	ret = btrfs_map_block(root->fs_info, BTRFS_MAP_DISCARD,
-			      bytenr, &num_bytes, &bbio, 0);
+	ret = btrfs_map_block(fs_info, BTRFS_MAP_DISCARD, bytenr, &num_bytes,
+			      &bbio, 0);
 	/* Error condition is -ENOMEM */
 	if (!ret) {
 		struct btrfs_bio_stripe *stripe = bbio->stripes;
@@ -2067,7 +2069,7 @@ int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr,
 		}
 		btrfs_put_bbio(bbio);
 	}
-	btrfs_bio_counter_dec(root->fs_info);
+	btrfs_bio_counter_dec(fs_info);
 
 	if (actual_bytes)
 		*actual_bytes = discarded_bytes;
@@ -2154,7 +2156,7 @@ static int __btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
 	path->reada = READA_FORWARD;
 	path->leave_spinning = 1;
 	/* now insert the actual backref */
-	ret = insert_extent_backref(trans, root->fs_info->extent_root,
+	ret = insert_extent_backref(trans, fs_info->extent_root,
 				    path, bytenr, parent, root_objectid,
 				    owner, offset, refs_to_add);
 	if (ret)
@@ -2170,6 +2172,7 @@ static int run_delayed_data_ref(struct btrfs_trans_handle *trans,
 				struct btrfs_delayed_extent_op *extent_op,
 				int insert_reserved)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	int ret = 0;
 	struct btrfs_delayed_data_ref *ref;
 	struct btrfs_key ins;
@@ -2182,7 +2185,7 @@ static int run_delayed_data_ref(struct btrfs_trans_handle *trans,
 	ins.type = BTRFS_EXTENT_ITEM_KEY;
 
 	ref = btrfs_delayed_node_to_data_ref(node);
-	trace_run_delayed_data_ref(root->fs_info, node, ref, node->action);
+	trace_run_delayed_data_ref(fs_info, node, ref, node->action);
 
 	if (node->type == BTRFS_SHARED_DATA_REF_KEY)
 		parent = ref->parent;
@@ -2234,6 +2237,7 @@ static int run_delayed_extent_op(struct btrfs_trans_handle *trans,
 				 struct btrfs_delayed_ref_node *node,
 				 struct btrfs_delayed_extent_op *extent_op)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct btrfs_key key;
 	struct btrfs_path *path;
 	struct btrfs_extent_item *ei;
@@ -2246,7 +2250,7 @@ static int run_delayed_extent_op(struct btrfs_trans_handle *trans,
 	if (trans->aborted)
 		return 0;
 
-	if (metadata && !btrfs_fs_incompat(root->fs_info, SKINNY_METADATA))
+	if (metadata && !btrfs_fs_incompat(fs_info, SKINNY_METADATA))
 		metadata = 0;
 
 	path = btrfs_alloc_path();
@@ -2266,8 +2270,7 @@ static int run_delayed_extent_op(struct btrfs_trans_handle *trans,
 again:
 	path->reada = READA_FORWARD;
 	path->leave_spinning = 1;
-	ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key,
-				path, 0, 1);
+	ret = btrfs_search_slot(trans, fs_info->extent_root, &key, path, 0, 1);
 	if (ret < 0) {
 		err = ret;
 		goto out;
@@ -2302,7 +2305,7 @@ again:
 	item_size = btrfs_item_size_nr(leaf, path->slots[0]);
 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
 	if (item_size < sizeof(*ei)) {
-		ret = convert_extent_item_v0(trans, root->fs_info->extent_root,
+		ret = convert_extent_item_v0(trans, fs_info->extent_root,
 					     path, (u64)-1, 0);
 		if (ret < 0) {
 			err = ret;
@@ -2328,16 +2331,16 @@ static int run_delayed_tree_ref(struct btrfs_trans_handle *trans,
 				struct btrfs_delayed_extent_op *extent_op,
 				int insert_reserved)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	int ret = 0;
 	struct btrfs_delayed_tree_ref *ref;
 	struct btrfs_key ins;
 	u64 parent = 0;
 	u64 ref_root = 0;
-	bool skinny_metadata = btrfs_fs_incompat(root->fs_info,
-						 SKINNY_METADATA);
+	bool skinny_metadata = btrfs_fs_incompat(fs_info, SKINNY_METADATA);
 
 	ref = btrfs_delayed_node_to_tree_ref(node);
-	trace_run_delayed_tree_ref(root->fs_info, node, ref, node->action);
+	trace_run_delayed_tree_ref(fs_info, node, ref, node->action);
 
 	if (node->type == BTRFS_SHARED_BLOCK_REF_KEY)
 		parent = ref->parent;
@@ -2388,6 +2391,7 @@ static int run_one_delayed_ref(struct btrfs_trans_handle *trans,
 			       struct btrfs_delayed_extent_op *extent_op,
 			       int insert_reserved)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	int ret = 0;
 
 	if (trans->aborted) {
@@ -2407,22 +2411,20 @@ static int run_one_delayed_ref(struct btrfs_trans_handle *trans,
 		 */
 		BUG_ON(extent_op);
 		head = btrfs_delayed_node_to_head(node);
-		trace_run_delayed_ref_head(root->fs_info, node, head,
-					   node->action);
+		trace_run_delayed_ref_head(fs_info, node, head, node->action);
 
 		if (insert_reserved) {
 			btrfs_pin_extent(root, node->bytenr,
 					 node->num_bytes, 1);
 			if (head->is_data) {
-				ret = btrfs_del_csums(trans, root->fs_info,
+				ret = btrfs_del_csums(trans, fs_info,
 						      node->bytenr,
 						      node->num_bytes);
 			}
 		}
 
 		/* Also free its reserved qgroup space */
-		btrfs_qgroup_free_delayed_ref(root->fs_info,
-					      head->qgroup_ref_root,
+		btrfs_qgroup_free_delayed_ref(fs_info, head->qgroup_ref_root,
 					      head->qgroup_reserved);
 		return ret;
 	}
@@ -2748,18 +2750,19 @@ static u64 find_middle(struct rb_root *root)
 
 static inline u64 heads_to_leaves(struct btrfs_root *root, u64 heads)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	u64 num_bytes;
 
 	num_bytes = heads * (sizeof(struct btrfs_extent_item) +
 			     sizeof(struct btrfs_extent_inline_ref));
-	if (!btrfs_fs_incompat(root->fs_info, SKINNY_METADATA))
+	if (!btrfs_fs_incompat(fs_info, SKINNY_METADATA))
 		num_bytes += heads * sizeof(struct btrfs_tree_block_info);
 
 	/*
 	 * We don't ever fill up leaves all the way so multiply by 2 just to be
 	 * closer to what we're really going to want to use.
 	 */
-	return div_u64(num_bytes, BTRFS_LEAF_DATA_SIZE(root->fs_info));
+	return div_u64(num_bytes, BTRFS_LEAF_DATA_SIZE(fs_info));
 }
 
 /*
@@ -2768,14 +2771,15 @@ static inline u64 heads_to_leaves(struct btrfs_root *root, u64 heads)
  */
 u64 btrfs_csum_bytes_to_leaves(struct btrfs_root *root, u64 csum_bytes)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	u64 csum_size;
 	u64 num_csums_per_leaf;
 	u64 num_csums;
 
-	csum_size = BTRFS_MAX_ITEM_SIZE(root->fs_info);
+	csum_size = BTRFS_MAX_ITEM_SIZE(fs_info);
 	num_csums_per_leaf = div64_u64(csum_size,
-			(u64)btrfs_super_csum_size(root->fs_info->super_copy));
-	num_csums = div64_u64(csum_bytes, root->fs_info->sectorsize);
+			(u64)btrfs_super_csum_size(fs_info->super_copy));
+	num_csums = div64_u64(csum_bytes, fs_info->sectorsize);
 	num_csums += num_csums_per_leaf - 1;
 	num_csums = div64_u64(num_csums, num_csums_per_leaf);
 	return num_csums;
@@ -2784,6 +2788,7 @@ u64 btrfs_csum_bytes_to_leaves(struct btrfs_root *root, u64 csum_bytes)
 int btrfs_check_space_for_delayed_refs(struct btrfs_trans_handle *trans,
 				       struct btrfs_root *root)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct btrfs_block_rsv *global_rsv;
 	u64 num_heads = trans->transaction->delayed_refs.num_heads_ready;
 	u64 csum_bytes = trans->transaction->delayed_refs.pending_csums;
@@ -2791,15 +2796,15 @@ int btrfs_check_space_for_delayed_refs(struct btrfs_trans_handle *trans,
 	u64 num_bytes, num_dirty_bgs_bytes;
 	int ret = 0;
 
-	num_bytes = btrfs_calc_trans_metadata_size(root->fs_info, 1);
+	num_bytes = btrfs_calc_trans_metadata_size(fs_info, 1);
 	num_heads = heads_to_leaves(root, num_heads);
 	if (num_heads > 1)
-		num_bytes += (num_heads - 1) * root->fs_info->nodesize;
+		num_bytes += (num_heads - 1) * fs_info->nodesize;
 	num_bytes <<= 1;
-	num_bytes += btrfs_csum_bytes_to_leaves(root, csum_bytes) * root->fs_info->nodesize;
-	num_dirty_bgs_bytes = btrfs_calc_trans_metadata_size(root->fs_info,
+	num_bytes += btrfs_csum_bytes_to_leaves(root, csum_bytes) * fs_info->nodesize;
+	num_dirty_bgs_bytes = btrfs_calc_trans_metadata_size(fs_info,
 							     num_dirty_bgs);
-	global_rsv = &root->fs_info->global_block_rsv;
+	global_rsv = &fs_info->global_block_rsv;
 
 	/*
 	 * If we can't allocate any more chunks lets make sure we have _lots_ of
@@ -2892,6 +2897,7 @@ done:
 int btrfs_async_run_delayed_refs(struct btrfs_root *root,
 				 unsigned long count, u64 transid, int wait)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct async_delayed_refs *async;
 	int ret;
 
@@ -2899,7 +2905,7 @@ int btrfs_async_run_delayed_refs(struct btrfs_root *root,
 	if (!async)
 		return -ENOMEM;
 
-	async->root = root->fs_info->tree_root;
+	async->root = fs_info->tree_root;
 	async->count = count;
 	async->error = 0;
 	async->transid = transid;
@@ -2912,7 +2918,7 @@ int btrfs_async_run_delayed_refs(struct btrfs_root *root,
 	btrfs_init_work(&async->work, btrfs_extent_refs_helper,
 			delayed_ref_async_start, NULL, NULL);
 
-	btrfs_queue_work(root->fs_info->extent_workers, &async->work);
+	btrfs_queue_work(fs_info->extent_workers, &async->work);
 
 	if (wait) {
 		wait_for_completion(&async->wait);
@@ -2936,6 +2942,7 @@ int btrfs_async_run_delayed_refs(struct btrfs_root *root,
 int btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,
 			   struct btrfs_root *root, unsigned long count)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct rb_node *node;
 	struct btrfs_delayed_ref_root *delayed_refs;
 	struct btrfs_delayed_ref_head *head;
@@ -2947,11 +2954,11 @@ int btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,
 	if (trans->aborted)
 		return 0;
 
-	if (test_bit(BTRFS_FS_CREATING_FREE_SPACE_TREE, &root->fs_info->flags))
+	if (test_bit(BTRFS_FS_CREATING_FREE_SPACE_TREE, &fs_info->flags))
 		return 0;
 
-	if (root == root->fs_info->extent_root)
-		root = root->fs_info->tree_root;
+	if (root == fs_info->extent_root)
+		root = fs_info->tree_root;
 
 	delayed_refs = &trans->transaction->delayed_refs;
 	if (count == 0)
@@ -3019,6 +3026,7 @@ int btrfs_set_disk_extent_flags(struct btrfs_trans_handle *trans,
 				u64 bytenr, u64 num_bytes, u64 flags,
 				int level, int is_data)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct btrfs_delayed_extent_op *extent_op;
 	int ret;
 
@@ -3032,7 +3040,7 @@ int btrfs_set_disk_extent_flags(struct btrfs_trans_handle *trans,
 	extent_op->is_data = is_data ? true : false;
 	extent_op->level = level;
 
-	ret = btrfs_add_delayed_extent_op(root->fs_info, trans, bytenr,
+	ret = btrfs_add_delayed_extent_op(fs_info, trans, bytenr,
 					  num_bytes, extent_op);
 	if (ret)
 		btrfs_free_delayed_extent_op(extent_op);
@@ -3106,7 +3114,8 @@ static noinline int check_committed_ref(struct btrfs_trans_handle *trans,
 					struct btrfs_path *path,
 					u64 objectid, u64 offset, u64 bytenr)
 {
-	struct btrfs_root *extent_root = root->fs_info->extent_root;
+	struct btrfs_fs_info *fs_info = root->fs_info;
+	struct btrfs_root *extent_root = fs_info->extent_root;
 	struct extent_buffer *leaf;
 	struct btrfs_extent_data_ref *ref;
 	struct btrfs_extent_inline_ref *iref;
@@ -3213,6 +3222,7 @@ static int __btrfs_mod_ref(struct btrfs_trans_handle *trans,
 			   struct extent_buffer *buf,
 			   int full_backref, int inc)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	u64 bytenr;
 	u64 num_bytes;
 	u64 parent;
@@ -3227,7 +3237,7 @@ static int __btrfs_mod_ref(struct btrfs_trans_handle *trans,
 			    u64, u64, u64, u64, u64, u64);
 
 
-	if (btrfs_is_testing(root->fs_info))
+	if (btrfs_is_testing(fs_info))
 		return 0;
 
 	ref_root = btrfs_header_owner(buf);
@@ -3270,7 +3280,7 @@ static int __btrfs_mod_ref(struct btrfs_trans_handle *trans,
 				goto fail;
 		} else {
 			bytenr = btrfs_node_blockptr(buf, i);
-			num_bytes = root->fs_info->nodesize;
+			num_bytes = fs_info->nodesize;
 			ret = process_func(trans, root, bytenr, num_bytes,
 					   parent, ref_root, level - 1, 0);
 			if (ret)
@@ -3300,7 +3310,8 @@ static int write_one_cache_group(struct btrfs_trans_handle *trans,
 				 struct btrfs_block_group_cache *cache)
 {
 	int ret;
-	struct btrfs_root *extent_root = root->fs_info->extent_root;
+	struct btrfs_fs_info *fs_info = root->fs_info;
+	struct btrfs_root *extent_root = fs_info->extent_root;
 	unsigned long bi;
 	struct extent_buffer *leaf;
 
@@ -3325,19 +3336,18 @@ static struct btrfs_block_group_cache *
 next_block_group(struct btrfs_root *root,
 		 struct btrfs_block_group_cache *cache)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct rb_node *node;
 
-	spin_lock(&root->fs_info->block_group_cache_lock);
+	spin_lock(&fs_info->block_group_cache_lock);
 
 	/* If our block group was removed, we need a full search. */
 	if (RB_EMPTY_NODE(&cache->cache_node)) {
 		const u64 next_bytenr = cache->key.objectid + cache->key.offset;
 
-		spin_unlock(&root->fs_info->block_group_cache_lock);
+		spin_unlock(&fs_info->block_group_cache_lock);
 		btrfs_put_block_group(cache);
-		cache = btrfs_lookup_first_block_group(root->fs_info,
-						       next_bytenr);
-		return cache;
+		cache = btrfs_lookup_first_block_group(fs_info, next_bytenr); return cache;
 	}
 	node = rb_next(&cache->cache_node);
 	btrfs_put_block_group(cache);
@@ -3347,7 +3357,7 @@ next_block_group(struct btrfs_root *root,
 		btrfs_get_block_group(cache);
 	} else
 		cache = NULL;
-	spin_unlock(&root->fs_info->block_group_cache_lock);
+	spin_unlock(&fs_info->block_group_cache_lock);
 	return cache;
 }
 
@@ -3355,7 +3365,8 @@ static int cache_save_setup(struct btrfs_block_group_cache *block_group,
 			    struct btrfs_trans_handle *trans,
 			    struct btrfs_path *path)
 {
-	struct btrfs_root *root = block_group->fs_info->tree_root;
+	struct btrfs_fs_info *fs_info = block_group->fs_info;
+	struct btrfs_root *root = fs_info->tree_root;
 	struct inode *inode = NULL;
 	u64 alloc_hint = 0;
 	int dcs = BTRFS_DC_ERROR;
@@ -3429,7 +3440,7 @@ again:
 
 	if (i_size_read(inode) > 0) {
 		ret = btrfs_check_trunc_cache_free_space(root,
-					&root->fs_info->global_block_rsv);
+					&fs_info->global_block_rsv);
 		if (ret)
 			goto out_put;
 
@@ -3440,7 +3451,7 @@ again:
 
 	spin_lock(&block_group->lock);
 	if (block_group->cached != BTRFS_CACHE_FINISHED ||
-	    !btrfs_test_opt(root->fs_info, SPACE_CACHE)) {
+	    !btrfs_test_opt(fs_info, SPACE_CACHE)) {
 		/*
 		 * don't bother trying to write stuff out _if_
 		 * a) we're not cached,
@@ -3511,12 +3522,13 @@ out:
 int btrfs_setup_space_cache(struct btrfs_trans_handle *trans,
 			    struct btrfs_root *root)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct btrfs_block_group_cache *cache, *tmp;
 	struct btrfs_transaction *cur_trans = trans->transaction;
 	struct btrfs_path *path;
 
 	if (list_empty(&cur_trans->dirty_bgs) ||
-	    !btrfs_test_opt(root->fs_info, SPACE_CACHE))
+	    !btrfs_test_opt(fs_info, SPACE_CACHE))
 		return 0;
 
 	path = btrfs_alloc_path();
@@ -3549,6 +3561,7 @@ int btrfs_setup_space_cache(struct btrfs_trans_handle *trans,
 int btrfs_start_dirty_block_groups(struct btrfs_trans_handle *trans,
 				   struct btrfs_root *root)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct btrfs_block_group_cache *cache;
 	struct btrfs_transaction *cur_trans = trans->transaction;
 	int ret = 0;
@@ -3622,7 +3635,7 @@ again:
 
 		if (cache->disk_cache_state == BTRFS_DC_SETUP) {
 			cache->io_ctl.inode = NULL;
-			ret = btrfs_write_out_cache(root->fs_info, trans,
+			ret = btrfs_write_out_cache(fs_info, trans,
 						    cache, path);
 			if (ret == 0 && cache->io_ctl.inode) {
 				num_started++;
@@ -3712,6 +3725,7 @@ again:
 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
 				   struct btrfs_root *root)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct btrfs_block_group_cache *cache;
 	struct btrfs_transaction *cur_trans = trans->transaction;
 	int ret = 0;
@@ -3775,7 +3789,7 @@ int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
 
 		if (!ret && cache->disk_cache_state == BTRFS_DC_SETUP) {
 			cache->io_ctl.inode = NULL;
-			ret = btrfs_write_out_cache(root->fs_info, trans,
+			ret = btrfs_write_out_cache(fs_info, trans,
 						    cache, path);
 			if (ret == 0 && cache->io_ctl.inode) {
 				num_started++;
@@ -3836,10 +3850,11 @@ int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
 
 int btrfs_extent_readonly(struct btrfs_root *root, u64 bytenr)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct btrfs_block_group_cache *block_group;
 	int readonly = 0;
 
-	block_group = btrfs_lookup_block_group(root->fs_info, bytenr);
+	block_group = btrfs_lookup_block_group(fs_info, bytenr);
 	if (!block_group || block_group->ro)
 		readonly = 1;
 	if (block_group)
@@ -4050,7 +4065,8 @@ static u64 get_restripe_target(struct btrfs_fs_info *fs_info, u64 flags)
  */
 static u64 btrfs_reduce_alloc_profile(struct btrfs_root *root, u64 flags)
 {
-	u64 num_devices = root->fs_info->fs_devices->rw_devices;
+	struct btrfs_fs_info *fs_info = root->fs_info;
+	u64 num_devices = fs_info->fs_devices->rw_devices;
 	u64 target;
 	u64 raid_type;
 	u64 allowed = 0;
@@ -4059,16 +4075,16 @@ static u64 btrfs_reduce_alloc_profile(struct btrfs_root *root, u64 flags)
 	 * see if restripe for this chunk_type is in progress, if so
 	 * try to reduce to the target profile
 	 */
-	spin_lock(&root->fs_info->balance_lock);
-	target = get_restripe_target(root->fs_info, flags);
+	spin_lock(&fs_info->balance_lock);
+	target = get_restripe_target(fs_info, flags);
 	if (target) {
 		/* pick target profile only if it's already available */
 		if ((flags & target) & BTRFS_EXTENDED_PROFILE_MASK) {
-			spin_unlock(&root->fs_info->balance_lock);
+			spin_unlock(&fs_info->balance_lock);
 			return extended_to_chunk(target);
 		}
 	}
-	spin_unlock(&root->fs_info->balance_lock);
+	spin_unlock(&fs_info->balance_lock);
 
 	/* First, mask out the RAID levels which aren't possible */
 	for (raid_type = 0; raid_type < BTRFS_NR_RAID_TYPES; raid_type++) {
@@ -4095,32 +4111,34 @@ static u64 btrfs_reduce_alloc_profile(struct btrfs_root *root, u64 flags)
 
 static u64 get_alloc_profile(struct btrfs_root *root, u64 orig_flags)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	unsigned seq;
 	u64 flags;
 
 	do {
 		flags = orig_flags;
-		seq = read_seqbegin(&root->fs_info->profiles_lock);
+		seq = read_seqbegin(&fs_info->profiles_lock);
 
 		if (flags & BTRFS_BLOCK_GROUP_DATA)
-			flags |= root->fs_info->avail_data_alloc_bits;
+			flags |= fs_info->avail_data_alloc_bits;
 		else if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
-			flags |= root->fs_info->avail_system_alloc_bits;
+			flags |= fs_info->avail_system_alloc_bits;
 		else if (flags & BTRFS_BLOCK_GROUP_METADATA)
-			flags |= root->fs_info->avail_metadata_alloc_bits;
-	} while (read_seqretry(&root->fs_info->profiles_lock, seq));
+			flags |= fs_info->avail_metadata_alloc_bits;
+	} while (read_seqretry(&fs_info->profiles_lock, seq));
 
 	return btrfs_reduce_alloc_profile(root, flags);
 }
 
 u64 btrfs_get_alloc_profile(struct btrfs_root *root, int data)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	u64 flags;
 	u64 ret;
 
 	if (data)
 		flags = BTRFS_BLOCK_GROUP_DATA;
-	else if (root == root->fs_info->chunk_root)
+	else if (root == fs_info->chunk_root)
 		flags = BTRFS_BLOCK_GROUP_SYSTEM;
 	else
 		flags = BTRFS_BLOCK_GROUP_METADATA;
@@ -4140,7 +4158,7 @@ int btrfs_alloc_data_chunk_ondemand(struct inode *inode, u64 bytes)
 	int have_pinned_space;
 
 	/* make sure bytes are sectorsize aligned */
-	bytes = ALIGN(bytes, root->fs_info->sectorsize);
+	bytes = ALIGN(bytes, fs_info->sectorsize);
 
 	if (btrfs_is_free_space_inode(inode)) {
 		need_commit = 0;
@@ -4186,7 +4204,7 @@ alloc:
 			if (IS_ERR(trans))
 				return PTR_ERR(trans);
 
-			ret = do_chunk_alloc(trans, root->fs_info->extent_root,
+			ret = do_chunk_alloc(trans, fs_info->extent_root,
 					     alloc_target,
 					     CHUNK_ALLOC_NO_FORCE);
 			btrfs_end_transaction(trans, root);
@@ -4218,12 +4236,13 @@ alloc:
 		/* commit the current transaction and try again */
 commit_trans:
 		if (need_commit &&
-		    !atomic_read(&root->fs_info->open_ioctl_trans)) {
+		    !atomic_read(&fs_info->open_ioctl_trans)) {
 			need_commit--;
 
 			if (need_commit > 0) {
 				btrfs_start_delalloc_roots(fs_info, 0, -1);
-				btrfs_wait_ordered_roots(fs_info, -1, 0, (u64)-1);
+				btrfs_wait_ordered_roots(fs_info, -1, 0,
+							 (u64)-1);
 			}
 
 			trans = btrfs_join_transaction(root);
@@ -4241,21 +4260,21 @@ commit_trans:
 				 * operations. Wait for it to finish so that
 				 * more space is released.
 				 */
-				mutex_lock(&root->fs_info->cleaner_delayed_iput_mutex);
-				mutex_unlock(&root->fs_info->cleaner_delayed_iput_mutex);
+				mutex_lock(&fs_info->cleaner_delayed_iput_mutex);
+				mutex_unlock(&fs_info->cleaner_delayed_iput_mutex);
 				goto again;
 			} else {
 				btrfs_end_transaction(trans, root);
 			}
 		}
 
-		trace_btrfs_space_reservation(root->fs_info,
+		trace_btrfs_space_reservation(fs_info,
 					      "space_info:enospc",
 					      data_sinfo->flags, bytes, 1);
 		return -ENOSPC;
 	}
 	data_sinfo->bytes_may_use += bytes;
-	trace_btrfs_space_reservation(root->fs_info, "space_info",
+	trace_btrfs_space_reservation(fs_info, "space_info",
 				      data_sinfo->flags, bytes, 1);
 	spin_unlock(&data_sinfo->lock);
 
@@ -4269,13 +4288,13 @@ commit_trans:
  */
 int btrfs_check_data_free_space(struct inode *inode, u64 start, u64 len)
 {
-	struct btrfs_root *root = BTRFS_I(inode)->root;
+	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
 	int ret;
 
 	/* align the range */
-	len = round_up(start + len, root->fs_info->sectorsize) -
-	      round_down(start, root->fs_info->sectorsize);
-	start = round_down(start, root->fs_info->sectorsize);
+	len = round_up(start + len, fs_info->sectorsize) -
+	      round_down(start, fs_info->sectorsize);
+	start = round_down(start, fs_info->sectorsize);
 
 	ret = btrfs_alloc_data_chunk_ondemand(inode, len);
 	if (ret < 0)
@@ -4299,21 +4318,21 @@ int btrfs_check_data_free_space(struct inode *inode, u64 start, u64 len)
 void btrfs_free_reserved_data_space_noquota(struct inode *inode, u64 start,
 					    u64 len)
 {
-	struct btrfs_root *root = BTRFS_I(inode)->root;
+	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
 	struct btrfs_space_info *data_sinfo;
 
 	/* Make sure the range is aligned to sectorsize */
-	len = round_up(start + len, root->fs_info->sectorsize) -
-	      round_down(start, root->fs_info->sectorsize);
-	start = round_down(start, root->fs_info->sectorsize);
+	len = round_up(start + len, fs_info->sectorsize) -
+	      round_down(start, fs_info->sectorsize);
+	start = round_down(start, fs_info->sectorsize);
 
-	data_sinfo = root->fs_info->data_sinfo;
+	data_sinfo = fs_info->data_sinfo;
 	spin_lock(&data_sinfo->lock);
 	if (WARN_ON(data_sinfo->bytes_may_use < len))
 		data_sinfo->bytes_may_use = 0;
 	else
 		data_sinfo->bytes_may_use -= len;
-	trace_btrfs_space_reservation(root->fs_info, "space_info",
+	trace_btrfs_space_reservation(fs_info, "space_info",
 				      data_sinfo->flags, len, 0);
 	spin_unlock(&data_sinfo->lock);
 }
@@ -4359,7 +4378,8 @@ static inline u64 calc_global_rsv_need_space(struct btrfs_block_rsv *global)
 static int should_alloc_chunk(struct btrfs_root *root,
 			      struct btrfs_space_info *sinfo, int force)
 {
-	struct btrfs_block_rsv *global_rsv = &root->fs_info->global_block_rsv;
+	struct btrfs_fs_info *fs_info = root->fs_info;
+	struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
 	u64 num_bytes = sinfo->total_bytes - sinfo->bytes_readonly;
 	u64 num_allocated = sinfo->bytes_used + sinfo->bytes_reserved;
 	u64 thresh;
@@ -4380,7 +4400,7 @@ static int should_alloc_chunk(struct btrfs_root *root,
 	 * about 1% of the FS size.
 	 */
 	if (force == CHUNK_ALLOC_LIMITED) {
-		thresh = btrfs_super_total_bytes(root->fs_info->super_copy);
+		thresh = btrfs_super_total_bytes(fs_info->super_copy);
 		thresh = max_t(u64, SZ_64M, div_factor_fine(thresh, 1));
 
 		if (num_bytes - num_allocated < thresh)
@@ -4394,13 +4414,14 @@ static int should_alloc_chunk(struct btrfs_root *root,
 
 static u64 get_profile_num_devs(struct btrfs_root *root, u64 type)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	u64 num_dev;
 
 	if (type & (BTRFS_BLOCK_GROUP_RAID10 |
 		    BTRFS_BLOCK_GROUP_RAID0 |
 		    BTRFS_BLOCK_GROUP_RAID5 |
 		    BTRFS_BLOCK_GROUP_RAID6))
-		num_dev = root->fs_info->fs_devices->rw_devices;
+		num_dev = fs_info->fs_devices->rw_devices;
 	else if (type & BTRFS_BLOCK_GROUP_RAID1)
 		num_dev = 2;
 	else
@@ -4418,6 +4439,7 @@ void check_system_chunk(struct btrfs_trans_handle *trans,
 			struct btrfs_root *root,
 			u64 type)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct btrfs_space_info *info;
 	u64 left;
 	u64 thresh;
@@ -4428,9 +4450,9 @@ void check_system_chunk(struct btrfs_trans_handle *trans,
 	 * Needed because we can end up allocating a system chunk and for an
 	 * atomic and race free space reservation in the chunk block reserve.
 	 */
-	ASSERT(mutex_is_locked(&root->fs_info->chunk_mutex));
+	ASSERT(mutex_is_locked(&fs_info->chunk_mutex));
 
-	info = __find_space_info(root->fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
+	info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
 	spin_lock(&info->lock);
 	left = info->total_bytes - info->bytes_used - info->bytes_pinned -
 		info->bytes_reserved - info->bytes_readonly -
@@ -4440,19 +4462,19 @@ void check_system_chunk(struct btrfs_trans_handle *trans,
 	num_devs = get_profile_num_devs(root, type);
 
 	/* num_devs device items to update and 1 chunk item to add or remove */
-	thresh = btrfs_calc_trunc_metadata_size(root->fs_info, num_devs) +
-		btrfs_calc_trans_metadata_size(root->fs_info, 1);
+	thresh = btrfs_calc_trunc_metadata_size(fs_info, num_devs) +
+		btrfs_calc_trans_metadata_size(fs_info, 1);
 
-	if (left < thresh && btrfs_test_opt(root->fs_info, ENOSPC_DEBUG)) {
-		btrfs_info(root->fs_info, "left=%llu, need=%llu, flags=%llu",
-			left, thresh, type);
-		dump_space_info(root->fs_info, info, 0, 0);
+	if (left < thresh && btrfs_test_opt(fs_info, ENOSPC_DEBUG)) {
+		btrfs_info(fs_info, "left=%llu, need=%llu, flags=%llu",
+			   left, thresh, type);
+		dump_space_info(fs_info, info, 0, 0);
 	}
 
 	if (left < thresh) {
 		u64 flags;
 
-		flags = btrfs_get_alloc_profile(root->fs_info->chunk_root, 0);
+		flags = btrfs_get_alloc_profile(fs_info->chunk_root, 0);
 		/*
 		 * Ignore failure to create system chunk. We might end up not
 		 * needing it, as we might not need to COW all nodes/leafs from
@@ -4463,8 +4485,8 @@ void check_system_chunk(struct btrfs_trans_handle *trans,
 	}
 
 	if (!ret) {
-		ret = btrfs_block_rsv_add(root->fs_info->chunk_root,
-					  &root->fs_info->chunk_block_rsv,
+		ret = btrfs_block_rsv_add(fs_info->chunk_root,
+					  &fs_info->chunk_block_rsv,
 					  thresh, BTRFS_RESERVE_NO_FLUSH);
 		if (!ret)
 			trans->chunk_bytes_reserved += thresh;
@@ -4492,10 +4514,9 @@ static int do_chunk_alloc(struct btrfs_trans_handle *trans,
 	if (trans->allocating_chunk)
 		return -ENOSPC;
 
-	space_info = __find_space_info(extent_root->fs_info, flags);
+	space_info = __find_space_info(fs_info, flags);
 	if (!space_info) {
-		ret = update_space_info(extent_root->fs_info, flags,
-					0, 0, 0, &space_info);
+		ret = update_space_info(fs_info, flags, 0, 0, 0, &space_info);
 		BUG_ON(ret); /* -ENOMEM */
 	}
 	BUG_ON(!space_info); /* Logic error */
@@ -4607,7 +4628,8 @@ static int can_overcommit(struct btrfs_root *root,
 			  struct btrfs_space_info *space_info, u64 bytes,
 			  enum btrfs_reserve_flush_enum flush)
 {
-	struct btrfs_block_rsv *global_rsv;
+	struct btrfs_fs_info *fs_info = root->fs_info;
+	struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
 	u64 profile;
 	u64 space_size;
 	u64 avail;
@@ -4617,8 +4639,6 @@ static int can_overcommit(struct btrfs_root *root,
 	if (space_info->flags & BTRFS_BLOCK_GROUP_DATA)
 		return 0;
 
-	BUG_ON(root->fs_info == NULL);
-	global_rsv = &root->fs_info->global_block_rsv;
 	profile = btrfs_get_alloc_profile(root, 0);
 	used = space_info->bytes_used + space_info->bytes_reserved +
 		space_info->bytes_pinned + space_info->bytes_readonly;
@@ -4637,9 +4657,9 @@ static int can_overcommit(struct btrfs_root *root,
 
 	used += space_info->bytes_may_use;
 
-	spin_lock(&root->fs_info->free_chunk_lock);
-	avail = root->fs_info->free_chunk_space;
-	spin_unlock(&root->fs_info->free_chunk_lock);
+	spin_lock(&fs_info->free_chunk_lock);
+	avail = fs_info->free_chunk_space;
+	spin_unlock(&fs_info->free_chunk_lock);
 
 	/*
 	 * If we have dup, raid1 or raid10 then only half of the free
@@ -4670,7 +4690,8 @@ static int can_overcommit(struct btrfs_root *root,
 static void btrfs_writeback_inodes_sb_nr(struct btrfs_root *root,
 					 unsigned long nr_pages, int nr_items)
 {
-	struct super_block *sb = root->fs_info->sb;
+	struct btrfs_fs_info *fs_info = root->fs_info;
+	struct super_block *sb = fs_info->sb;
 
 	if (down_read_trylock(&sb->s_umount)) {
 		writeback_inodes_sb_nr(sb, nr_pages, WB_REASON_FS_FREE_SPACE);
@@ -4683,10 +4704,9 @@ static void btrfs_writeback_inodes_sb_nr(struct btrfs_root *root,
 		 * the filesystem is readonly(all dirty pages are written to
 		 * the disk).
 		 */
-		btrfs_start_delalloc_roots(root->fs_info, 0, nr_items);
+		btrfs_start_delalloc_roots(fs_info, 0, nr_items);
 		if (!current->journal_info)
-			btrfs_wait_ordered_roots(root->fs_info, nr_items,
-						 0, (u64)-1);
+			btrfs_wait_ordered_roots(fs_info, nr_items, 0, (u64)-1);
 	}
 }
 
@@ -4710,6 +4730,7 @@ static inline int calc_reclaim_items_nr(struct btrfs_root *root, u64 to_reclaim)
 static void shrink_delalloc(struct btrfs_root *root, u64 to_reclaim, u64 orig,
 			    bool wait_ordered)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct btrfs_block_rsv *block_rsv;
 	struct btrfs_space_info *space_info;
 	struct btrfs_trans_handle *trans;
@@ -4726,17 +4747,16 @@ static void shrink_delalloc(struct btrfs_root *root, u64 to_reclaim, u64 orig,
 	to_reclaim = (u64)items * EXTENT_SIZE_PER_ITEM;
 
 	trans = (struct btrfs_trans_handle *)current->journal_info;
-	block_rsv = &root->fs_info->delalloc_block_rsv;
+	block_rsv = &fs_info->delalloc_block_rsv;
 	space_info = block_rsv->space_info;
 
 	delalloc_bytes = percpu_counter_sum_positive(
-						&root->fs_info->delalloc_bytes);
+						&fs_info->delalloc_bytes);
 	if (delalloc_bytes == 0) {
 		if (trans)
 			return;
 		if (wait_ordered)
-			btrfs_wait_ordered_roots(root->fs_info, items,
-						 0, (u64)-1);
+			btrfs_wait_ordered_roots(fs_info, items, 0, (u64)-1);
 		return;
 	}
 
@@ -4749,7 +4769,7 @@ static void shrink_delalloc(struct btrfs_root *root, u64 to_reclaim, u64 orig,
 		 * We need to wait for the async pages to actually start before
 		 * we do anything.
 		 */
-		max_reclaim = atomic_read(&root->fs_info->async_delalloc_pages);
+		max_reclaim = atomic_read(&fs_info->async_delalloc_pages);
 		if (!max_reclaim)
 			goto skip_async;
 
@@ -4758,8 +4778,8 @@ static void shrink_delalloc(struct btrfs_root *root, u64 to_reclaim, u64 orig,
 		else
 			max_reclaim -= nr_pages;
 
-		wait_event(root->fs_info->async_submit_wait,
-			   atomic_read(&root->fs_info->async_delalloc_pages) <=
+		wait_event(fs_info->async_submit_wait,
+			   atomic_read(&fs_info->async_delalloc_pages) <=
 			   (int)max_reclaim);
 skip_async:
 		if (!trans)
@@ -4780,15 +4800,14 @@ skip_async:
 
 		loops++;
 		if (wait_ordered && !trans) {
-			btrfs_wait_ordered_roots(root->fs_info, items,
-						 0, (u64)-1);
+			btrfs_wait_ordered_roots(fs_info, items, 0, (u64)-1);
 		} else {
 			time_left = schedule_timeout_killable(1);
 			if (time_left)
 				break;
 		}
 		delalloc_bytes = percpu_counter_sum_positive(
-						&root->fs_info->delalloc_bytes);
+						&fs_info->delalloc_bytes);
 	}
 }
 
@@ -4806,7 +4825,8 @@ static int may_commit_transaction(struct btrfs_root *root,
 				  struct btrfs_space_info *space_info,
 				  u64 bytes, int force)
 {
-	struct btrfs_block_rsv *delayed_rsv = &root->fs_info->delayed_block_rsv;
+	struct btrfs_fs_info *fs_info = root->fs_info;
+	struct btrfs_block_rsv *delayed_rsv = &fs_info->delayed_block_rsv;
 	struct btrfs_trans_handle *trans;
 
 	trans = (struct btrfs_trans_handle *)current->journal_info;
@@ -4855,6 +4875,7 @@ static int flush_space(struct btrfs_root *root,
 		       struct btrfs_space_info *space_info, u64 num_bytes,
 		       u64 orig_bytes, int state)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct btrfs_trans_handle *trans;
 	int nr;
 	int ret = 0;
@@ -4886,7 +4907,7 @@ static int flush_space(struct btrfs_root *root,
 			ret = PTR_ERR(trans);
 			break;
 		}
-		ret = do_chunk_alloc(trans, root->fs_info->extent_root,
+		ret = do_chunk_alloc(trans, fs_info->extent_root,
 				     btrfs_get_alloc_profile(root, 0),
 				     CHUNK_ALLOC_NO_FORCE);
 		btrfs_end_transaction(trans, root);
@@ -4901,7 +4922,7 @@ static int flush_space(struct btrfs_root *root,
 		break;
 	}
 
-	trace_btrfs_flush_space(root->fs_info, space_info->flags, num_bytes,
+	trace_btrfs_flush_space(fs_info, space_info->flags, num_bytes,
 				orig_bytes, state, ret);
 	return ret;
 }
@@ -4947,6 +4968,7 @@ btrfs_calc_reclaim_metadata_size(struct btrfs_root *root,
 static inline int need_do_async_reclaim(struct btrfs_space_info *space_info,
 					struct btrfs_root *root, u64 used)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	u64 thresh = div_factor_fine(space_info->total_bytes, 98);
 
 	/* If we're just plain full then async reclaim just slows us down. */
@@ -4956,9 +4978,8 @@ static inline int need_do_async_reclaim(struct btrfs_space_info *space_info,
 	if (!btrfs_calc_reclaim_metadata_size(root, space_info))
 		return 0;
 
-	return (used >= thresh && !btrfs_fs_closing(root->fs_info) &&
-		!test_bit(BTRFS_FS_STATE_REMOUNTING,
-			  &root->fs_info->fs_state));
+	return (used >= thresh && !btrfs_fs_closing(fs_info) &&
+		!test_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state));
 }
 
 static void wake_all_tickets(struct list_head *head)
@@ -5138,6 +5159,7 @@ static int __reserve_metadata_bytes(struct btrfs_root *root,
 				    u64 orig_bytes,
 				    enum btrfs_reserve_flush_enum flush)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct reserve_ticket ticket;
 	u64 used;
 	int ret = 0;
@@ -5158,15 +5180,13 @@ static int __reserve_metadata_bytes(struct btrfs_root *root,
 	 */
 	if (used + orig_bytes <= space_info->total_bytes) {
 		space_info->bytes_may_use += orig_bytes;
-		trace_btrfs_space_reservation(root->fs_info, "space_info",
-					      space_info->flags, orig_bytes,
-					      1);
+		trace_btrfs_space_reservation(fs_info, "space_info",
+					      space_info->flags, orig_bytes, 1);
 		ret = 0;
 	} else if (can_overcommit(root, space_info, orig_bytes, flush)) {
 		space_info->bytes_may_use += orig_bytes;
-		trace_btrfs_space_reservation(root->fs_info, "space_info",
-					      space_info->flags, orig_bytes,
-					      1);
+		trace_btrfs_space_reservation(fs_info, "space_info",
+					      space_info->flags, orig_bytes, 1);
 		ret = 0;
 	}
 
@@ -5185,7 +5205,7 @@ static int __reserve_metadata_bytes(struct btrfs_root *root,
 			list_add_tail(&ticket.list, &space_info->tickets);
 			if (!space_info->flush) {
 				space_info->flush = 1;
-				trace_btrfs_trigger_flush(root->fs_info,
+				trace_btrfs_trigger_flush(fs_info,
 							  space_info->flags,
 							  orig_bytes, flush,
 							  "enospc");
@@ -5203,15 +5223,13 @@ static int __reserve_metadata_bytes(struct btrfs_root *root,
 		 * which means we won't have fs_info->fs_root set, so don't do
 		 * the async reclaim as we will panic.
 		 */
-		if (!test_bit(BTRFS_FS_LOG_RECOVERING, &root->fs_info->flags) &&
+		if (!test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags) &&
 		    need_do_async_reclaim(space_info, root, used) &&
-		    !work_busy(&root->fs_info->async_reclaim_work)) {
-			trace_btrfs_trigger_flush(root->fs_info,
-						  space_info->flags,
-						  orig_bytes, flush,
-						  "preempt");
+		    !work_busy(&fs_info->async_reclaim_work)) {
+			trace_btrfs_trigger_flush(fs_info, space_info->flags,
+						  orig_bytes, flush, "preempt");
 			queue_work(system_unbound_wq,
-				   &root->fs_info->async_reclaim_work);
+				   &fs_info->async_reclaim_work);
 		}
 	}
 	spin_unlock(&space_info->lock);
@@ -5219,19 +5237,19 @@ static int __reserve_metadata_bytes(struct btrfs_root *root,
 		return ret;
 
 	if (flush == BTRFS_RESERVE_FLUSH_ALL)
-		return wait_reserve_ticket(root->fs_info, space_info, &ticket,
+		return wait_reserve_ticket(fs_info, space_info, &ticket,
 					   orig_bytes);
 
 	ret = 0;
-	priority_reclaim_metadata_space(root->fs_info, space_info, &ticket);
+	priority_reclaim_metadata_space(fs_info, space_info, &ticket);
 	spin_lock(&space_info->lock);
 	if (ticket.bytes) {
 		if (ticket.bytes < orig_bytes) {
 			u64 num_bytes = orig_bytes - ticket.bytes;
 			space_info->bytes_may_use -= num_bytes;
-			trace_btrfs_space_reservation(root->fs_info,
-					"space_info", space_info->flags,
-					num_bytes, 0);
+			trace_btrfs_space_reservation(fs_info, "space_info",
+						      space_info->flags,
+						      num_bytes, 0);
 
 		}
 		list_del_init(&ticket.list);
@@ -5261,22 +5279,20 @@ static int reserve_metadata_bytes(struct btrfs_root *root,
 				  u64 orig_bytes,
 				  enum btrfs_reserve_flush_enum flush)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
+	struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
 	int ret;
 
 	ret = __reserve_metadata_bytes(root, block_rsv->space_info, orig_bytes,
 				       flush);
 	if (ret == -ENOSPC &&
 	    unlikely(root->orphan_cleanup_state == ORPHAN_CLEANUP_STARTED)) {
-		struct btrfs_block_rsv *global_rsv =
-			&root->fs_info->global_block_rsv;
-
 		if (block_rsv != global_rsv &&
 		    !block_rsv_use_bytes(global_rsv, orig_bytes))
 			ret = 0;
 	}
 	if (ret == -ENOSPC)
-		trace_btrfs_space_reservation(root->fs_info,
-					      "space_info:enospc",
+		trace_btrfs_space_reservation(fs_info, "space_info:enospc",
 					      block_rsv->space_info->flags,
 					      orig_bytes, 1);
 	return ret;
@@ -5286,18 +5302,19 @@ static struct btrfs_block_rsv *get_block_rsv(
 					const struct btrfs_trans_handle *trans,
 					const struct btrfs_root *root)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct btrfs_block_rsv *block_rsv = NULL;
 
 	if (test_bit(BTRFS_ROOT_REF_COWS, &root->state) ||
-	    (root == root->fs_info->csum_root && trans->adding_csums) ||
-	     (root == root->fs_info->uuid_root))
+	    (root == fs_info->csum_root && trans->adding_csums) ||
+	    (root == fs_info->uuid_root))
 		block_rsv = trans->block_rsv;
 
 	if (!block_rsv)
 		block_rsv = root->block_rsv;
 
 	if (!block_rsv)
-		block_rsv = &root->fs_info->empty_block_rsv;
+		block_rsv = &fs_info->empty_block_rsv;
 
 	return block_rsv;
 }
@@ -5619,12 +5636,13 @@ void btrfs_block_rsv_release(struct btrfs_root *root,
 			     struct btrfs_block_rsv *block_rsv,
 			     u64 num_bytes)
 {
-	struct btrfs_block_rsv *global_rsv = &root->fs_info->global_block_rsv;
+	struct btrfs_fs_info *fs_info = root->fs_info;
+	struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
+
 	if (global_rsv == block_rsv ||
 	    block_rsv->space_info != global_rsv->space_info)
 		global_rsv = NULL;
-	block_rsv_release_bytes(root->fs_info, block_rsv, global_rsv,
-				num_bytes);
+	block_rsv_release_bytes(fs_info, block_rsv, global_rsv, num_bytes);
 }
 
 static void update_global_block_rsv(struct btrfs_fs_info *fs_info)
@@ -5721,13 +5739,15 @@ static void release_global_block_rsv(struct btrfs_fs_info *fs_info)
 void btrfs_trans_release_metadata(struct btrfs_trans_handle *trans,
 				  struct btrfs_root *root)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
+
 	if (!trans->block_rsv)
 		return;
 
 	if (!trans->bytes_reserved)
 		return;
 
-	trace_btrfs_space_reservation(root->fs_info, "transaction",
+	trace_btrfs_space_reservation(fs_info, "transaction",
 				      trans->transid, trans->bytes_reserved, 0);
 	btrfs_block_rsv_release(root, trans->block_rsv, trans->bytes_reserved);
 	trans->bytes_reserved = 0;
@@ -5755,6 +5775,7 @@ void btrfs_trans_release_chunk_metadata(struct btrfs_trans_handle *trans)
 int btrfs_orphan_reserve_metadata(struct btrfs_trans_handle *trans,
 				  struct inode *inode)
 {
+	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
 	struct btrfs_root *root = BTRFS_I(inode)->root;
 	/*
 	 * We always use trans->block_rsv here as we will have reserved space
@@ -5770,17 +5791,20 @@ int btrfs_orphan_reserve_metadata(struct btrfs_trans_handle *trans,
 	 * added it, so this takes the reservation so we can release it later
 	 * when we are truly done with the orphan item.
 	 */
-	u64 num_bytes = btrfs_calc_trans_metadata_size(root->fs_info, 1);
-	trace_btrfs_space_reservation(root->fs_info, "orphan",
+	u64 num_bytes = btrfs_calc_trans_metadata_size(fs_info, 1);
+
+	trace_btrfs_space_reservation(fs_info, "orphan",
 				      btrfs_ino(inode), num_bytes, 1);
 	return btrfs_block_rsv_migrate(src_rsv, dst_rsv, num_bytes, 1);
 }
 
 void btrfs_orphan_release_metadata(struct inode *inode)
 {
+	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
 	struct btrfs_root *root = BTRFS_I(inode)->root;
-	u64 num_bytes = btrfs_calc_trans_metadata_size(root->fs_info, 1);
-	trace_btrfs_space_reservation(root->fs_info, "orphan",
+	u64 num_bytes = btrfs_calc_trans_metadata_size(fs_info, 1);
+
+	trace_btrfs_space_reservation(fs_info, "orphan",
 				      btrfs_ino(inode), num_bytes, 0);
 	btrfs_block_rsv_release(root, root->orphan_block_rsv, num_bytes);
 }
@@ -5807,11 +5831,12 @@ int btrfs_subvolume_reserve_metadata(struct btrfs_root *root,
 {
 	u64 num_bytes;
 	int ret;
-	struct btrfs_block_rsv *global_rsv = &root->fs_info->global_block_rsv;
+	struct btrfs_fs_info *fs_info = root->fs_info;
+	struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
 
-	if (test_bit(BTRFS_FS_QUOTA_ENABLED, &root->fs_info->flags)) {
+	if (test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags)) {
 		/* One for parent inode, two for dir entries */
-		num_bytes = 3 * root->fs_info->nodesize;
+		num_bytes = 3 * fs_info->nodesize;
 		ret = btrfs_qgroup_reserve_meta(root, num_bytes);
 		if (ret)
 			return ret;
@@ -5821,8 +5846,8 @@ int btrfs_subvolume_reserve_metadata(struct btrfs_root *root,
 
 	*qgroup_reserved = num_bytes;
 
-	num_bytes = btrfs_calc_trans_metadata_size(root->fs_info, items);
-	rsv->space_info = __find_space_info(root->fs_info,
+	num_bytes = btrfs_calc_trans_metadata_size(fs_info, items);
+	rsv->space_info = __find_space_info(fs_info,
 					    BTRFS_BLOCK_GROUP_METADATA);
 	ret = btrfs_block_rsv_add(root, rsv, num_bytes,
 				  BTRFS_RESERVE_FLUSH_ALL);
@@ -5906,6 +5931,7 @@ static unsigned drop_outstanding_extent(struct inode *inode, u64 num_bytes)
 static u64 calc_csum_metadata_size(struct inode *inode, u64 num_bytes,
 				   int reserve)
 {
+	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
 	struct btrfs_root *root = BTRFS_I(inode)->root;
 	u64 old_csums, num_csums;
 
@@ -5925,17 +5951,17 @@ static u64 calc_csum_metadata_size(struct inode *inode, u64 num_bytes,
 		return 0;
 
 	if (reserve)
-		return btrfs_calc_trans_metadata_size(root->fs_info,
+		return btrfs_calc_trans_metadata_size(fs_info,
 						      num_csums - old_csums);
 
-	return btrfs_calc_trans_metadata_size(root->fs_info,
-					      old_csums - num_csums);
+	return btrfs_calc_trans_metadata_size(fs_info, old_csums - num_csums);
 }
 
 int btrfs_delalloc_reserve_metadata(struct inode *inode, u64 num_bytes)
 {
+	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
 	struct btrfs_root *root = BTRFS_I(inode)->root;
-	struct btrfs_block_rsv *block_rsv = &root->fs_info->delalloc_block_rsv;
+	struct btrfs_block_rsv *block_rsv = &fs_info->delalloc_block_rsv;
 	u64 to_reserve = 0;
 	u64 csum_bytes;
 	unsigned nr_extents = 0;
@@ -5962,13 +5988,13 @@ int btrfs_delalloc_reserve_metadata(struct inode *inode, u64 num_bytes)
 	}
 
 	if (flush != BTRFS_RESERVE_NO_FLUSH &&
-	    btrfs_transaction_in_commit(root->fs_info))
+	    btrfs_transaction_in_commit(fs_info))
 		schedule_timeout(1);
 
 	if (delalloc_lock)
 		mutex_lock(&BTRFS_I(inode)->delalloc_mutex);
 
-	num_bytes = ALIGN(num_bytes, root->fs_info->sectorsize);
+	num_bytes = ALIGN(num_bytes, fs_info->sectorsize);
 
 	spin_lock(&BTRFS_I(inode)->lock);
 	nr_extents = (unsigned)div64_u64(num_bytes +
@@ -5983,15 +6009,14 @@ int btrfs_delalloc_reserve_metadata(struct inode *inode, u64 num_bytes)
 			BTRFS_I(inode)->reserved_extents;
 
 	/* We always want to reserve a slot for updating the inode. */
-	to_reserve = btrfs_calc_trans_metadata_size(root->fs_info,
-						    nr_extents + 1);
+	to_reserve = btrfs_calc_trans_metadata_size(fs_info, nr_extents + 1);
 	to_reserve += calc_csum_metadata_size(inode, num_bytes, 1);
 	csum_bytes = BTRFS_I(inode)->csum_bytes;
 	spin_unlock(&BTRFS_I(inode)->lock);
 
-	if (test_bit(BTRFS_FS_QUOTA_ENABLED, &root->fs_info->flags)) {
+	if (test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags)) {
 		ret = btrfs_qgroup_reserve_meta(root,
-				nr_extents * root->fs_info->nodesize);
+				nr_extents * fs_info->nodesize);
 		if (ret)
 			goto out_fail;
 	}
@@ -5999,14 +6024,14 @@ int btrfs_delalloc_reserve_metadata(struct inode *inode, u64 num_bytes)
 	ret = btrfs_block_rsv_add(root, block_rsv, to_reserve, flush);
 	if (unlikely(ret)) {
 		btrfs_qgroup_free_meta(root,
-				       nr_extents * root->fs_info->nodesize);
+				       nr_extents * fs_info->nodesize);
 		goto out_fail;
 	}
 
 	spin_lock(&BTRFS_I(inode)->lock);
 	if (test_and_set_bit(BTRFS_INODE_DELALLOC_META_RESERVED,
 			     &BTRFS_I(inode)->runtime_flags)) {
-		to_reserve -= btrfs_calc_trans_metadata_size(root->fs_info, 1);
+		to_reserve -= btrfs_calc_trans_metadata_size(fs_info, 1);
 		release_extra = true;
 	}
 	BTRFS_I(inode)->reserved_extents += nr_extents;
@@ -6016,11 +6041,11 @@ int btrfs_delalloc_reserve_metadata(struct inode *inode, u64 num_bytes)
 		mutex_unlock(&BTRFS_I(inode)->delalloc_mutex);
 
 	if (to_reserve)
-		trace_btrfs_space_reservation(root->fs_info, "delalloc",
+		trace_btrfs_space_reservation(fs_info, "delalloc",
 					      btrfs_ino(inode), to_reserve, 1);
 	if (release_extra)
 		btrfs_block_rsv_release(root, block_rsv,
-			btrfs_calc_trans_metadata_size(root->fs_info, 1));
+				btrfs_calc_trans_metadata_size(fs_info, 1));
 	return 0;
 
 out_fail:
@@ -6075,12 +6100,11 @@ out_fail:
 	}
 	spin_unlock(&BTRFS_I(inode)->lock);
 	if (dropped)
-		to_free += btrfs_calc_trans_metadata_size(root->fs_info,
-							  dropped);
+		to_free += btrfs_calc_trans_metadata_size(fs_info, dropped);
 
 	if (to_free) {
 		btrfs_block_rsv_release(root, block_rsv, to_free);
-		trace_btrfs_space_reservation(root->fs_info, "delalloc",
+		trace_btrfs_space_reservation(fs_info, "delalloc",
 					      btrfs_ino(inode), to_free, 0);
 	}
 	if (delalloc_lock)
@@ -6099,11 +6123,12 @@ out_fail:
  */
 void btrfs_delalloc_release_metadata(struct inode *inode, u64 num_bytes)
 {
+	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
 	struct btrfs_root *root = BTRFS_I(inode)->root;
 	u64 to_free = 0;
 	unsigned dropped;
 
-	num_bytes = ALIGN(num_bytes, root->fs_info->sectorsize);
+	num_bytes = ALIGN(num_bytes, fs_info->sectorsize);
 	spin_lock(&BTRFS_I(inode)->lock);
 	dropped = drop_outstanding_extent(inode, num_bytes);
 
@@ -6111,17 +6136,15 @@ void btrfs_delalloc_release_metadata(struct inode *inode, u64 num_bytes)
 		to_free = calc_csum_metadata_size(inode, num_bytes, 0);
 	spin_unlock(&BTRFS_I(inode)->lock);
 	if (dropped > 0)
-		to_free += btrfs_calc_trans_metadata_size(root->fs_info,
-							  dropped);
+		to_free += btrfs_calc_trans_metadata_size(fs_info, dropped);
 
-	if (btrfs_is_testing(root->fs_info))
+	if (btrfs_is_testing(fs_info))
 		return;
 
-	trace_btrfs_space_reservation(root->fs_info, "delalloc",
+	trace_btrfs_space_reservation(fs_info, "delalloc",
 				      btrfs_ino(inode), to_free, 0);
 
-	btrfs_block_rsv_release(root, &root->fs_info->delalloc_block_rsv,
-				to_free);
+	btrfs_block_rsv_release(root, &fs_info->delalloc_block_rsv, to_free);
 }
 
 /**
@@ -6251,7 +6274,7 @@ static int update_block_group(struct btrfs_trans_handle *trans,
 			spin_unlock(&cache->lock);
 			spin_unlock(&cache->space_info->lock);
 
-			trace_btrfs_space_reservation(root->fs_info, "pinned",
+			trace_btrfs_space_reservation(info, "pinned",
 						      cache->space_info->flags,
 						      num_bytes, 1);
 			set_extent_dirty(info->pinned_extents,
@@ -6293,17 +6316,18 @@ static int update_block_group(struct btrfs_trans_handle *trans,
 
 static u64 first_logical_byte(struct btrfs_root *root, u64 search_start)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct btrfs_block_group_cache *cache;
 	u64 bytenr;
 
-	spin_lock(&root->fs_info->block_group_cache_lock);
-	bytenr = root->fs_info->first_logical_byte;
-	spin_unlock(&root->fs_info->block_group_cache_lock);
+	spin_lock(&fs_info->block_group_cache_lock);
+	bytenr = fs_info->first_logical_byte;
+	spin_unlock(&fs_info->block_group_cache_lock);
 
 	if (bytenr < (u64)-1)
 		return bytenr;
 
-	cache = btrfs_lookup_first_block_group(root->fs_info, search_start);
+	cache = btrfs_lookup_first_block_group(fs_info, search_start);
 	if (!cache)
 		return 0;
 
@@ -6317,6 +6341,8 @@ static int pin_down_extent(struct btrfs_root *root,
 			   struct btrfs_block_group_cache *cache,
 			   u64 bytenr, u64 num_bytes, int reserved)
 {
+	struct btrfs_fs_info *fs_info = cache->fs_info;
+
 	spin_lock(&cache->space_info->lock);
 	spin_lock(&cache->lock);
 	cache->pinned += num_bytes;
@@ -6328,9 +6354,9 @@ static int pin_down_extent(struct btrfs_root *root,
 	spin_unlock(&cache->lock);
 	spin_unlock(&cache->space_info->lock);
 
-	trace_btrfs_space_reservation(root->fs_info, "pinned",
+	trace_btrfs_space_reservation(fs_info, "pinned",
 				      cache->space_info->flags, num_bytes, 1);
-	set_extent_dirty(root->fs_info->pinned_extents, bytenr,
+	set_extent_dirty(fs_info->pinned_extents, bytenr,
 			 bytenr + num_bytes - 1, GFP_NOFS | __GFP_NOFAIL);
 	return 0;
 }
@@ -6341,9 +6367,10 @@ static int pin_down_extent(struct btrfs_root *root,
 int btrfs_pin_extent(struct btrfs_root *root,
 		     u64 bytenr, u64 num_bytes, int reserved)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct btrfs_block_group_cache *cache;
 
-	cache = btrfs_lookup_block_group(root->fs_info, bytenr);
+	cache = btrfs_lookup_block_group(fs_info, bytenr);
 	BUG_ON(!cache); /* Logic error */
 
 	pin_down_extent(root, cache, bytenr, num_bytes, reserved);
@@ -6358,10 +6385,11 @@ int btrfs_pin_extent(struct btrfs_root *root,
 int btrfs_pin_extent_for_log_replay(struct btrfs_root *root,
 				    u64 bytenr, u64 num_bytes)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct btrfs_block_group_cache *cache;
 	int ret;
 
-	cache = btrfs_lookup_block_group(root->fs_info, bytenr);
+	cache = btrfs_lookup_block_group(fs_info, bytenr);
 	if (!cache)
 		return -EINVAL;
 
@@ -6383,11 +6411,12 @@ int btrfs_pin_extent_for_log_replay(struct btrfs_root *root,
 
 static int __exclude_logged_extent(struct btrfs_root *root, u64 start, u64 num_bytes)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	int ret;
 	struct btrfs_block_group_cache *block_group;
 	struct btrfs_caching_control *caching_ctl;
 
-	block_group = btrfs_lookup_block_group(root->fs_info, start);
+	block_group = btrfs_lookup_block_group(fs_info, start);
 	if (!block_group)
 		return -EINVAL;
 
@@ -6615,8 +6644,9 @@ static struct btrfs_free_cluster *
 fetch_cluster_info(struct btrfs_root *root, struct btrfs_space_info *space_info,
 		   u64 *empty_cluster)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct btrfs_free_cluster *ret = NULL;
-	bool ssd = btrfs_test_opt(root->fs_info, SSD);
+	bool ssd = btrfs_test_opt(fs_info, SSD);
 
 	*empty_cluster = 0;
 	if (btrfs_mixed_space_info(space_info))
@@ -6625,11 +6655,11 @@ fetch_cluster_info(struct btrfs_root *root, struct btrfs_space_info *space_info,
 	if (ssd)
 		*empty_cluster = SZ_2M;
 	if (space_info->flags & BTRFS_BLOCK_GROUP_METADATA) {
-		ret = &root->fs_info->meta_alloc_cluster;
+		ret = &fs_info->meta_alloc_cluster;
 		if (!ssd)
 			*empty_cluster = SZ_64K;
 	} else if ((space_info->flags & BTRFS_BLOCK_GROUP_DATA) && ssd) {
-		ret = &root->fs_info->data_alloc_cluster;
+		ret = &fs_info->data_alloc_cluster;
 	}
 
 	return ret;
@@ -6761,7 +6791,7 @@ int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
 			break;
 		}
 
-		if (btrfs_test_opt(root->fs_info, DISCARD))
+		if (btrfs_test_opt(fs_info, DISCARD))
 			ret = btrfs_discard_extent(root, start,
 						   end + 1 - start, NULL);
 
@@ -6847,8 +6877,7 @@ static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
 	u64 bytenr = node->bytenr;
 	u64 num_bytes = node->num_bytes;
 	int last_ref = 0;
-	bool skinny_metadata = btrfs_fs_incompat(root->fs_info,
-						 SKINNY_METADATA);
+	bool skinny_metadata = btrfs_fs_incompat(info, SKINNY_METADATA);
 
 	path = btrfs_alloc_path();
 	if (!path)
@@ -7048,7 +7077,7 @@ static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
 				goto out;
 			}
 		}
-		add_pinned_bytes(root->fs_info, -num_bytes, owner_objectid,
+		add_pinned_bytes(info, -num_bytes, owner_objectid,
 				 root_objectid);
 	} else {
 		if (found_extent) {
@@ -7080,15 +7109,13 @@ static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
 			}
 		}
 
-		ret = add_to_free_space_tree(trans, root->fs_info, bytenr,
-					     num_bytes);
+		ret = add_to_free_space_tree(trans, info, bytenr, num_bytes);
 		if (ret) {
 			btrfs_abort_transaction(trans, ret);
 			goto out;
 		}
 
-		ret = update_block_group(trans, root->fs_info, bytenr,
-					 num_bytes, 0);
+		ret = update_block_group(trans, info, bytenr, num_bytes, 0);
 		if (ret) {
 			btrfs_abort_transaction(trans, ret);
 			goto out;
@@ -7178,15 +7205,17 @@ void btrfs_free_tree_block(struct btrfs_trans_handle *trans,
 			   struct extent_buffer *buf,
 			   u64 parent, int last_ref)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	int pin = 1;
 	int ret;
 
 	if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
-		ret = btrfs_add_delayed_tree_ref(root->fs_info, trans,
-					buf->start, buf->len,
-					parent, root->root_key.objectid,
-					btrfs_header_level(buf),
-					BTRFS_DROP_DELAYED_REF, NULL);
+		ret = btrfs_add_delayed_tree_ref(fs_info, trans,
+						 buf->start, buf->len,
+						 parent,
+						 root->root_key.objectid,
+						 btrfs_header_level(buf),
+						 BTRFS_DROP_DELAYED_REF, NULL);
 		BUG_ON(ret); /* -ENOMEM */
 	}
 
@@ -7202,7 +7231,7 @@ void btrfs_free_tree_block(struct btrfs_trans_handle *trans,
 				goto out;
 		}
 
-		cache = btrfs_lookup_block_group(root->fs_info, buf->start);
+		cache = btrfs_lookup_block_group(fs_info, buf->start);
 
 		if (btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) {
 			pin_down_extent(root, cache, buf->start, buf->len, 1);
@@ -7220,8 +7249,7 @@ void btrfs_free_tree_block(struct btrfs_trans_handle *trans,
 	}
 out:
 	if (pin)
-		add_pinned_bytes(root->fs_info, buf->len,
-				 btrfs_header_level(buf),
+		add_pinned_bytes(fs_info, buf->len, btrfs_header_level(buf),
 				 root->root_key.objectid);
 
 	/*
@@ -7242,7 +7270,7 @@ int btrfs_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 	if (btrfs_is_testing(fs_info))
 		return 0;
 
-	add_pinned_bytes(root->fs_info, num_bytes, owner, root_objectid);
+	add_pinned_bytes(fs_info, num_bytes, owner, root_objectid);
 
 	/*
 	 * tree log blocks never actually go into the extent allocation
@@ -7442,8 +7470,9 @@ static noinline int find_free_extent(struct btrfs_root *orig_root,
 				u64 hint_byte, struct btrfs_key *ins,
 				u64 flags, int delalloc)
 {
+	struct btrfs_fs_info *fs_info = orig_root->fs_info;
 	int ret = 0;
-	struct btrfs_root *root = orig_root->fs_info->extent_root;
+	struct btrfs_root *root = fs_info->extent_root;
 	struct btrfs_free_cluster *last_ptr = NULL;
 	struct btrfs_block_group_cache *block_group = NULL;
 	u64 search_start = 0;
@@ -7459,16 +7488,16 @@ static noinline int find_free_extent(struct btrfs_root *orig_root,
 	bool orig_have_caching_bg = false;
 	bool full_search = false;
 
-	WARN_ON(num_bytes < root->fs_info->sectorsize);
+	WARN_ON(num_bytes < fs_info->sectorsize);
 	ins->type = BTRFS_EXTENT_ITEM_KEY;
 	ins->objectid = 0;
 	ins->offset = 0;
 
 	trace_find_free_extent(orig_root, num_bytes, empty_size, flags);
 
-	space_info = __find_space_info(root->fs_info, flags);
+	space_info = __find_space_info(fs_info, flags);
 	if (!space_info) {
-		btrfs_err(root->fs_info, "No space info for %llu", flags);
+		btrfs_err(fs_info, "No space info for %llu", flags);
 		return -ENOSPC;
 	}
 
@@ -7515,8 +7544,7 @@ static noinline int find_free_extent(struct btrfs_root *orig_root,
 	search_start = max(search_start, first_logical_byte(root, 0));
 	search_start = max(search_start, hint_byte);
 	if (search_start == hint_byte) {
-		block_group = btrfs_lookup_block_group(root->fs_info,
-						       search_start);
+		block_group = btrfs_lookup_block_group(fs_info, search_start);
 		/*
 		 * we don't want to use the block group if it doesn't match our
 		 * allocation bits, or if its not cached.
@@ -7769,7 +7797,7 @@ unclustered_alloc:
 			goto loop;
 		}
 checks:
-		search_start = ALIGN(offset, root->fs_info->stripesize);
+		search_start = ALIGN(offset, fs_info->stripesize);
 
 		/* move on to the next group */
 		if (search_start + num_bytes >
@@ -7968,7 +7996,7 @@ int btrfs_reserve_extent(struct btrfs_root *root, u64 ram_bytes,
 
 	flags = btrfs_get_alloc_profile(root, is_data);
 again:
-	WARN_ON(num_bytes < root->fs_info->sectorsize);
+	WARN_ON(num_bytes < fs_info->sectorsize);
 	ret = find_free_extent(root, ram_bytes, num_bytes, empty_size,
 			       hint_byte, ins, flags, delalloc);
 	if (!ret && !is_data) {
@@ -7977,7 +8005,7 @@ again:
 		if (!final_tried && ins->offset) {
 			num_bytes = min(num_bytes >> 1, ins->offset);
 			num_bytes = round_down(num_bytes,
-					       root->fs_info->sectorsize);
+					       fs_info->sectorsize);
 			num_bytes = max(num_bytes, min_alloc_size);
 			ram_bytes = num_bytes;
 			if (num_bytes == min_alloc_size)
@@ -7987,7 +8015,7 @@ again:
 			struct btrfs_space_info *sinfo;
 
 			sinfo = __find_space_info(fs_info, flags);
-			btrfs_err(root->fs_info,
+			btrfs_err(fs_info,
 				  "allocation failed flags %llu, wanted %llu",
 				  flags, num_bytes);
 			if (sinfo)
@@ -8002,20 +8030,21 @@ static int __btrfs_free_reserved_extent(struct btrfs_root *root,
 					u64 start, u64 len,
 					int pin, int delalloc)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct btrfs_block_group_cache *cache;
 	int ret = 0;
 
-	cache = btrfs_lookup_block_group(root->fs_info, start);
+	cache = btrfs_lookup_block_group(fs_info, start);
 	if (!cache) {
-		btrfs_err(root->fs_info, "Unable to find block group for %llu",
-			start);
+		btrfs_err(fs_info, "Unable to find block group for %llu",
+			  start);
 		return -ENOSPC;
 	}
 
 	if (pin)
 		pin_down_extent(root, cache, start, len, 1);
 	else {
-		if (btrfs_test_opt(root->fs_info, DISCARD))
+		if (btrfs_test_opt(fs_info, DISCARD))
 			ret = btrfs_discard_extent(root, start, len, NULL);
 		btrfs_add_free_space(cache, start, len);
 		btrfs_free_reserved_bytes(cache, len, delalloc);
@@ -8130,8 +8159,7 @@ static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
 	struct extent_buffer *leaf;
 	u32 size = sizeof(*extent_item) + sizeof(*iref);
 	u64 num_bytes = ins->offset;
-	bool skinny_metadata = btrfs_fs_incompat(root->fs_info,
-						 SKINNY_METADATA);
+	bool skinny_metadata = btrfs_fs_incompat(fs_info, SKINNY_METADATA);
 
 	if (!skinny_metadata)
 		size += sizeof(*block_info);
@@ -8139,7 +8167,7 @@ static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
 	path = btrfs_alloc_path();
 	if (!path) {
 		btrfs_free_and_pin_reserved_extent(root, ins->objectid,
-						   root->fs_info->nodesize);
+						   fs_info->nodesize);
 		return -ENOMEM;
 	}
 
@@ -8149,7 +8177,7 @@ static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
 	if (ret) {
 		btrfs_free_path(path);
 		btrfs_free_and_pin_reserved_extent(root, ins->objectid,
-						   root->fs_info->nodesize);
+						   fs_info->nodesize);
 		return ret;
 	}
 
@@ -8163,7 +8191,7 @@ static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
 
 	if (skinny_metadata) {
 		iref = (struct btrfs_extent_inline_ref *)(extent_item + 1);
-		num_bytes = root->fs_info->nodesize;
+		num_bytes = fs_info->nodesize;
 	} else {
 		block_info = (struct btrfs_tree_block_info *)(extent_item + 1);
 		btrfs_set_tree_block_key(leaf, block_info, key);
@@ -8199,7 +8227,7 @@ static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
 	}
 
 	trace_btrfs_reserved_extent_alloc(root, ins->objectid,
-					  root->fs_info->nodesize);
+					  fs_info->nodesize);
 	return ret;
 }
 
@@ -8209,11 +8237,12 @@ int btrfs_alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
 				     u64 offset, u64 ram_bytes,
 				     struct btrfs_key *ins)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	int ret;
 
 	BUG_ON(root_objectid == BTRFS_TREE_LOG_OBJECTID);
 
-	ret = btrfs_add_delayed_data_ref(root->fs_info, trans, ins->objectid,
+	ret = btrfs_add_delayed_data_ref(fs_info, trans, ins->objectid,
 					 ins->offset, 0,
 					 root_objectid, owner, offset,
 					 ram_bytes, BTRFS_ADD_DELAYED_EXTENT,
@@ -8231,6 +8260,7 @@ int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans,
 				   u64 root_objectid, u64 owner, u64 offset,
 				   struct btrfs_key *ins)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	int ret;
 	struct btrfs_block_group_cache *block_group;
 	struct btrfs_space_info *space_info;
@@ -8239,13 +8269,13 @@ int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans,
 	 * Mixed block groups will exclude before processing the log so we only
 	 * need to do the exclude dance if this fs isn't mixed.
 	 */
-	if (!btrfs_fs_incompat(root->fs_info, MIXED_GROUPS)) {
+	if (!btrfs_fs_incompat(fs_info, MIXED_GROUPS)) {
 		ret = __exclude_logged_extent(root, ins->objectid, ins->offset);
 		if (ret)
 			return ret;
 	}
 
-	block_group = btrfs_lookup_block_group(root->fs_info, ins->objectid);
+	block_group = btrfs_lookup_block_group(fs_info, ins->objectid);
 	if (!block_group)
 		return -EINVAL;
 
@@ -8267,6 +8297,7 @@ static struct extent_buffer *
 btrfs_init_new_buffer(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 		      u64 bytenr, int level)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct extent_buffer *buf;
 
 	buf = btrfs_find_create_tree_block(root, bytenr);
@@ -8276,7 +8307,7 @@ btrfs_init_new_buffer(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 	btrfs_set_header_generation(buf, trans->transid);
 	btrfs_set_buffer_lockdep_class(root->root_key.objectid, buf, level);
 	btrfs_tree_lock(buf);
-	clean_tree_block(trans, root->fs_info, buf);
+	clean_tree_block(trans, fs_info, buf);
 	clear_bit(EXTENT_BUFFER_STALE, &buf->bflags);
 
 	btrfs_set_lock_blocking(buf);
@@ -8308,8 +8339,9 @@ static struct btrfs_block_rsv *
 use_block_rsv(struct btrfs_trans_handle *trans,
 	      struct btrfs_root *root, u32 blocksize)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct btrfs_block_rsv *block_rsv;
-	struct btrfs_block_rsv *global_rsv = &root->fs_info->global_block_rsv;
+	struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
 	int ret;
 	bool global_updated = false;
 
@@ -8327,11 +8359,11 @@ again:
 
 	if (block_rsv->type == BTRFS_BLOCK_RSV_GLOBAL && !global_updated) {
 		global_updated = true;
-		update_global_block_rsv(root->fs_info);
+		update_global_block_rsv(fs_info);
 		goto again;
 	}
 
-	if (btrfs_test_opt(root->fs_info, ENOSPC_DEBUG)) {
+	if (btrfs_test_opt(fs_info, ENOSPC_DEBUG)) {
 		static DEFINE_RATELIMIT_STATE(_rs,
 				DEFAULT_RATELIMIT_INTERVAL * 10,
 				/*DEFAULT_RATELIMIT_BURST*/ 1);
@@ -8375,18 +8407,18 @@ struct extent_buffer *btrfs_alloc_tree_block(struct btrfs_trans_handle *trans,
 					struct btrfs_disk_key *key, int level,
 					u64 hint, u64 empty_size)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct btrfs_key ins;
 	struct btrfs_block_rsv *block_rsv;
 	struct extent_buffer *buf;
 	struct btrfs_delayed_extent_op *extent_op;
 	u64 flags = 0;
 	int ret;
-	u32 blocksize = root->fs_info->nodesize;
-	bool skinny_metadata = btrfs_fs_incompat(root->fs_info,
-						 SKINNY_METADATA);
+	u32 blocksize = fs_info->nodesize;
+	bool skinny_metadata = btrfs_fs_incompat(fs_info, SKINNY_METADATA);
 
 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
-	if (btrfs_is_testing(root->fs_info)) {
+	if (btrfs_is_testing(fs_info)) {
 		buf = btrfs_init_new_buffer(trans, root, root->alloc_bytenr,
 					    level);
 		if (!IS_ERR(buf))
@@ -8433,7 +8465,7 @@ struct extent_buffer *btrfs_alloc_tree_block(struct btrfs_trans_handle *trans,
 		extent_op->is_data = false;
 		extent_op->level = level;
 
-		ret = btrfs_add_delayed_tree_ref(root->fs_info, trans,
+		ret = btrfs_add_delayed_tree_ref(fs_info, trans,
 						 ins.objectid, ins.offset,
 						 parent, root_objectid, level,
 						 BTRFS_ADD_DELAYED_EXTENT,
@@ -8450,7 +8482,7 @@ out_free_buf:
 out_free_reserved:
 	btrfs_free_reserved_extent(root, ins.objectid, ins.offset, 0);
 out_unuse:
-	unuse_block_rsv(root->fs_info, block_rsv, blocksize);
+	unuse_block_rsv(fs_info, block_rsv, blocksize);
 	return ERR_PTR(ret);
 }
 
@@ -8476,6 +8508,7 @@ static noinline void reada_walk_down(struct btrfs_trans_handle *trans,
 				     struct walk_control *wc,
 				     struct btrfs_path *path)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	u64 bytenr;
 	u64 generation;
 	u64 refs;
@@ -8493,7 +8526,7 @@ static noinline void reada_walk_down(struct btrfs_trans_handle *trans,
 	} else {
 		wc->reada_count = wc->reada_count * 3 / 2;
 		wc->reada_count = min_t(int, wc->reada_count,
-					BTRFS_NODEPTRS_PER_BLOCK(root->fs_info));
+					BTRFS_NODEPTRS_PER_BLOCK(fs_info));
 	}
 
 	eb = path->nodes[wc->level];
@@ -8644,6 +8677,7 @@ static noinline int do_walk_down(struct btrfs_trans_handle *trans,
 				 struct btrfs_path *path,
 				 struct walk_control *wc, int *lookup_info)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	u64 bytenr;
 	u64 generation;
 	u64 parent;
@@ -8669,9 +8703,9 @@ static noinline int do_walk_down(struct btrfs_trans_handle *trans,
 	}
 
 	bytenr = btrfs_node_blockptr(path->nodes[level], path->slots[level]);
-	blocksize = root->fs_info->nodesize;
+	blocksize = fs_info->nodesize;
 
-	next = find_extent_buffer(root->fs_info, bytenr);
+	next = find_extent_buffer(fs_info, bytenr);
 	if (!next) {
 		next = btrfs_find_create_tree_block(root, bytenr);
 		if (IS_ERR(next))
@@ -8691,7 +8725,7 @@ static noinline int do_walk_down(struct btrfs_trans_handle *trans,
 		goto out_unlock;
 
 	if (unlikely(wc->refs[level - 1] == 0)) {
-		btrfs_err(root->fs_info, "Missing references.");
+		btrfs_err(fs_info, "Missing references.");
 		ret = -EIO;
 		goto out_unlock;
 	}
@@ -8781,7 +8815,7 @@ skip:
 			ret = btrfs_qgroup_trace_subtree(trans, root, next,
 							 generation, level - 1);
 			if (ret) {
-				btrfs_err_rl(root->fs_info,
+				btrfs_err_rl(fs_info,
 					     "Error %d accounting shared subtree. Quota is out of sync, rescan required.",
 					     ret);
 			}
@@ -8819,6 +8853,7 @@ static noinline int walk_up_proc(struct btrfs_trans_handle *trans,
 				 struct btrfs_path *path,
 				 struct walk_control *wc)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	int ret;
 	int level = wc->level;
 	struct extent_buffer *eb = path->nodes[level];
@@ -8878,7 +8913,7 @@ static noinline int walk_up_proc(struct btrfs_trans_handle *trans,
 			BUG_ON(ret); /* -ENOMEM */
 			ret = btrfs_qgroup_trace_leaf_items(trans, root, eb);
 			if (ret) {
-				btrfs_err_rl(root->fs_info,
+				btrfs_err_rl(fs_info,
 					     "error %d accounting leaf items. Quota is out of sync, rescan required.",
 					     ret);
 			}
@@ -8890,7 +8925,7 @@ static noinline int walk_up_proc(struct btrfs_trans_handle *trans,
 			btrfs_set_lock_blocking(eb);
 			path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
 		}
-		clean_tree_block(trans, root->fs_info, eb);
+		clean_tree_block(trans, fs_info, eb);
 	}
 
 	if (eb == root->node) {
@@ -9094,7 +9129,7 @@ int btrfs_drop_snapshot(struct btrfs_root *root,
 	wc->update_ref = update_ref;
 	wc->keep_locks = 0;
 	wc->for_reloc = for_reloc;
-	wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(root->fs_info);
+	wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(fs_info);
 
 	while (1) {
 
@@ -9219,6 +9254,7 @@ int btrfs_drop_subtree(struct btrfs_trans_handle *trans,
 			struct extent_buffer *node,
 			struct extent_buffer *parent)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct btrfs_path *path;
 	struct walk_control *wc;
 	int level;
@@ -9258,7 +9294,7 @@ int btrfs_drop_subtree(struct btrfs_trans_handle *trans,
 	wc->update_ref = 0;
 	wc->keep_locks = 1;
 	wc->for_reloc = 1;
-	wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(root->fs_info);
+	wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(fs_info);
 
 	while (1) {
 		wret = walk_down_tree(trans, root, path, wc);
@@ -9377,6 +9413,7 @@ int btrfs_inc_block_group_ro(struct btrfs_root *root,
 			     struct btrfs_block_group_cache *cache)
 
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct btrfs_trans_handle *trans;
 	u64 alloc_flags;
 	int ret;
@@ -9391,11 +9428,11 @@ again:
 	 * block groups cache has started writing.  If it already started,
 	 * back off and let this transaction commit
 	 */
-	mutex_lock(&root->fs_info->ro_block_group_mutex);
+	mutex_lock(&fs_info->ro_block_group_mutex);
 	if (test_bit(BTRFS_TRANS_DIRTY_BG_RUN, &trans->transaction->flags)) {
 		u64 transid = trans->transid;
 
-		mutex_unlock(&root->fs_info->ro_block_group_mutex);
+		mutex_unlock(&fs_info->ro_block_group_mutex);
 		btrfs_end_transaction(trans, root);
 
 		ret = btrfs_wait_for_commit(root, transid);
@@ -9408,7 +9445,7 @@ again:
 	 * if we are changing raid levels, try to allocate a corresponding
 	 * block group with the new raid level.
 	 */
-	alloc_flags = update_block_group_flags(root->fs_info, cache->flags);
+	alloc_flags = update_block_group_flags(fs_info, cache->flags);
 	if (alloc_flags != cache->flags) {
 		ret = do_chunk_alloc(trans, root, alloc_flags,
 				     CHUNK_ALLOC_FORCE);
@@ -9434,13 +9471,12 @@ again:
 	ret = inc_block_group_ro(cache, 0);
 out:
 	if (cache->flags & BTRFS_BLOCK_GROUP_SYSTEM) {
-		alloc_flags = update_block_group_flags(root->fs_info,
-						       cache->flags);
-		lock_chunks(root->fs_info);
+		alloc_flags = update_block_group_flags(fs_info, cache->flags);
+		lock_chunks(fs_info);
 		check_system_chunk(trans, root, alloc_flags);
-		unlock_chunks(root->fs_info);
+		unlock_chunks(fs_info);
 	}
-	mutex_unlock(&root->fs_info->ro_block_group_mutex);
+	mutex_unlock(&fs_info->ro_block_group_mutex);
 
 	btrfs_end_transaction(trans, root);
 	return ret;
@@ -9527,7 +9563,7 @@ int btrfs_can_relocate(struct btrfs_fs_info *fs_info, u64 bytenr)
 	struct btrfs_root *root = fs_info->extent_root;
 	struct btrfs_block_group_cache *block_group;
 	struct btrfs_space_info *space_info;
-	struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
+	struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
 	struct btrfs_device *device;
 	struct btrfs_trans_handle *trans;
 	u64 min_free;
@@ -9539,14 +9575,14 @@ int btrfs_can_relocate(struct btrfs_fs_info *fs_info, u64 bytenr)
 	int full = 0;
 	int ret = 0;
 
-	debug = btrfs_test_opt(root->fs_info, ENOSPC_DEBUG);
+	debug = btrfs_test_opt(fs_info, ENOSPC_DEBUG);
 
-	block_group = btrfs_lookup_block_group(root->fs_info, bytenr);
+	block_group = btrfs_lookup_block_group(fs_info, bytenr);
 
 	/* odd, couldn't find the block group, leave it alone */
 	if (!block_group) {
 		if (debug)
-			btrfs_warn(root->fs_info,
+			btrfs_warn(fs_info,
 				   "can't find block group for bytenr %llu",
 				   bytenr);
 		return -1;
@@ -9596,7 +9632,7 @@ int btrfs_can_relocate(struct btrfs_fs_info *fs_info, u64 bytenr)
 	 *      3: raid0
 	 *      4: single
 	 */
-	target = get_restripe_target(root->fs_info, block_group->flags);
+	target = get_restripe_target(fs_info, block_group->flags);
 	if (target) {
 		index = __get_raid_index(extended_to_chunk(target));
 	} else {
@@ -9606,9 +9642,9 @@ int btrfs_can_relocate(struct btrfs_fs_info *fs_info, u64 bytenr)
 		 */
 		if (full) {
 			if (debug)
-				btrfs_warn(root->fs_info,
-					"no space to alloc new chunk for block group %llu",
-					block_group->key.objectid);
+				btrfs_warn(fs_info,
+					   "no space to alloc new chunk for block group %llu",
+					   block_group->key.objectid);
 			goto out;
 		}
 
@@ -9636,7 +9672,7 @@ int btrfs_can_relocate(struct btrfs_fs_info *fs_info, u64 bytenr)
 		goto out;
 	}
 
-	mutex_lock(&root->fs_info->chunk_mutex);
+	mutex_lock(&fs_info->chunk_mutex);
 	list_for_each_entry(device, &fs_devices->alloc_list, dev_alloc_list) {
 		u64 dev_offset;
 
@@ -9658,10 +9694,10 @@ int btrfs_can_relocate(struct btrfs_fs_info *fs_info, u64 bytenr)
 		}
 	}
 	if (debug && ret == -1)
-		btrfs_warn(root->fs_info,
-			"no space to allocate a new chunk for block group %llu",
-			block_group->key.objectid);
-	mutex_unlock(&root->fs_info->chunk_mutex);
+		btrfs_warn(fs_info,
+			   "no space to allocate a new chunk for block group %llu",
+			   block_group->key.objectid);
+	mutex_unlock(&fs_info->chunk_mutex);
 	btrfs_end_transaction(trans, root);
 out:
 	btrfs_put_block_group(block_group);
@@ -9706,7 +9742,7 @@ static int find_first_block_group(struct btrfs_fs_info *fs_info,
 						   found_key.offset);
 			read_unlock(&em_tree->lock);
 			if (!em) {
-				btrfs_err(root->fs_info,
+				btrfs_err(fs_info,
 			"logical %llu len %llu found bg but no related chunk",
 					  found_key.objectid, found_key.offset);
 				ret = -ENOENT;
@@ -9898,6 +9934,7 @@ out_err:
 static struct btrfs_block_group_cache *
 btrfs_create_block_group_cache(struct btrfs_root *root, u64 start, u64 size)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct btrfs_block_group_cache *cache;
 
 	cache = kzalloc(sizeof(*cache), GFP_NOFS);
@@ -9915,11 +9952,10 @@ btrfs_create_block_group_cache(struct btrfs_root *root, u64 start, u64 size)
 	cache->key.offset = size;
 	cache->key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
 
-	cache->sectorsize = root->fs_info->sectorsize;
-	cache->fs_info = root->fs_info;
+	cache->sectorsize = fs_info->sectorsize;
+	cache->fs_info = fs_info;
 	cache->full_stripe_len = btrfs_full_stripe_len(root,
-					       &root->fs_info->mapping_tree,
-					       start);
+					       &fs_info->mapping_tree, start);
 	set_free_space_tree_thresholds(cache);
 
 	atomic_set(&cache->count, 1);
@@ -9964,11 +10000,11 @@ int btrfs_read_block_groups(struct btrfs_fs_info *info)
 		return -ENOMEM;
 	path->reada = READA_FORWARD;
 
-	cache_gen = btrfs_super_cache_generation(root->fs_info->super_copy);
-	if (btrfs_test_opt(root->fs_info, SPACE_CACHE) &&
-	    btrfs_super_generation(root->fs_info->super_copy) != cache_gen)
+	cache_gen = btrfs_super_cache_generation(info->super_copy);
+	if (btrfs_test_opt(info, SPACE_CACHE) &&
+	    btrfs_super_generation(info->super_copy) != cache_gen)
 		need_clear = 1;
-	if (btrfs_test_opt(root->fs_info, CLEAR_CACHE))
+	if (btrfs_test_opt(info, CLEAR_CACHE))
 		need_clear = 1;
 
 	while (1) {
@@ -9999,7 +10035,7 @@ int btrfs_read_block_groups(struct btrfs_fs_info *info)
 			 * b) Setting 'dirty flag' makes sure that we flush
 			 *    the new space cache info onto disk.
 			 */
-			if (btrfs_test_opt(root->fs_info, SPACE_CACHE))
+			if (btrfs_test_opt(info, SPACE_CACHE))
 				cache->disk_cache_state = BTRFS_DC_CLEAR;
 		}
 
@@ -10050,21 +10086,21 @@ int btrfs_read_block_groups(struct btrfs_fs_info *info)
 		} else if (btrfs_block_group_used(&cache->item) == 0) {
 			cache->last_byte_to_unpin = (u64)-1;
 			cache->cached = BTRFS_CACHE_FINISHED;
-			add_new_free_space(cache, root->fs_info,
+			add_new_free_space(cache, info,
 					   found_key.objectid,
 					   found_key.objectid +
 					   found_key.offset);
 			free_excluded_extents(root, cache);
 		}
 
-		ret = btrfs_add_block_group_cache(root->fs_info, cache);
+		ret = btrfs_add_block_group_cache(info, cache);
 		if (ret) {
 			btrfs_remove_free_space_cache(cache);
 			btrfs_put_block_group(cache);
 			goto error;
 		}
 
-		trace_btrfs_add_block_group(root->fs_info, cache, 0);
+		trace_btrfs_add_block_group(info, cache, 0);
 		ret = update_space_info(info, cache->flags, found_key.offset,
 					btrfs_block_group_used(&cache->item),
 					cache->bytes_super, &space_info);
@@ -10083,7 +10119,7 @@ int btrfs_read_block_groups(struct btrfs_fs_info *info)
 
 		__link_block_group(space_info, cache);
 
-		set_avail_alloc_bits(root->fs_info, cache->flags);
+		set_avail_alloc_bits(info, cache->flags);
 		if (btrfs_chunk_readonly(root, cache->key.objectid)) {
 			inc_block_group_ro(cache, 1);
 		} else if (btrfs_block_group_used(&cache->item) == 0) {
@@ -10098,7 +10134,7 @@ int btrfs_read_block_groups(struct btrfs_fs_info *info)
 		}
 	}
 
-	list_for_each_entry_rcu(space_info, &root->fs_info->space_info, list) {
+	list_for_each_entry_rcu(space_info, &info->space_info, list) {
 		if (!(get_alloc_profile(root, space_info->flags) &
 		      (BTRFS_BLOCK_GROUP_RAID10 |
 		       BTRFS_BLOCK_GROUP_RAID1 |
@@ -10130,8 +10166,9 @@ error:
 void btrfs_create_pending_block_groups(struct btrfs_trans_handle *trans,
 				       struct btrfs_root *root)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct btrfs_block_group_cache *block_group, *tmp;
-	struct btrfs_root *extent_root = root->fs_info->extent_root;
+	struct btrfs_root *extent_root = fs_info->extent_root;
 	struct btrfs_block_group_item item;
 	struct btrfs_key key;
 	int ret = 0;
@@ -10151,11 +10188,11 @@ void btrfs_create_pending_block_groups(struct btrfs_trans_handle *trans,
 					sizeof(item));
 		if (ret)
 			btrfs_abort_transaction(trans, ret);
-		ret = btrfs_finish_chunk_alloc(trans, extent_root->fs_info,
-					       key.objectid, key.offset);
+		ret = btrfs_finish_chunk_alloc(trans, fs_info, key.objectid,
+					       key.offset);
 		if (ret)
 			btrfs_abort_transaction(trans, ret);
-		add_block_group_free_space(trans, root->fs_info, block_group);
+		add_block_group_free_space(trans, fs_info, block_group);
 		/* already aborted the transaction if it failed. */
 next:
 		list_del_init(&block_group->bg_list);
@@ -10168,12 +10205,11 @@ int btrfs_make_block_group(struct btrfs_trans_handle *trans,
 			   u64 type, u64 chunk_objectid, u64 chunk_offset,
 			   u64 size)
 {
-	int ret;
-	struct btrfs_root *extent_root;
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct btrfs_block_group_cache *cache;
-	extent_root = root->fs_info->extent_root;
+	int ret;
 
-	btrfs_set_log_full_commit(root->fs_info, trans);
+	btrfs_set_log_full_commit(fs_info, trans);
 
 	cache = btrfs_create_block_group_cache(root, chunk_offset, size);
 	if (!cache)
@@ -10198,8 +10234,7 @@ int btrfs_make_block_group(struct btrfs_trans_handle *trans,
 		return ret;
 	}
 
-	add_new_free_space(cache, root->fs_info, chunk_offset,
-			   chunk_offset + size);
+	add_new_free_space(cache, fs_info, chunk_offset, chunk_offset + size);
 
 	free_excluded_extents(root, cache);
 
@@ -10216,7 +10251,7 @@ int btrfs_make_block_group(struct btrfs_trans_handle *trans,
 	 * assigned to our block group, but don't update its counters just yet.
 	 * We want our bg to be added to the rbtree with its ->space_info set.
 	 */
-	ret = update_space_info(root->fs_info, cache->flags, 0, 0, 0,
+	ret = update_space_info(fs_info, cache->flags, 0, 0, 0,
 				&cache->space_info);
 	if (ret) {
 		btrfs_remove_free_space_cache(cache);
@@ -10224,7 +10259,7 @@ int btrfs_make_block_group(struct btrfs_trans_handle *trans,
 		return ret;
 	}
 
-	ret = btrfs_add_block_group_cache(root->fs_info, cache);
+	ret = btrfs_add_block_group_cache(fs_info, cache);
 	if (ret) {
 		btrfs_remove_free_space_cache(cache);
 		btrfs_put_block_group(cache);
@@ -10235,26 +10270,26 @@ int btrfs_make_block_group(struct btrfs_trans_handle *trans,
 	 * Now that our block group has its ->space_info set and is inserted in
 	 * the rbtree, update the space info's counters.
 	 */
-	trace_btrfs_add_block_group(root->fs_info, cache, 1);
-	ret = update_space_info(root->fs_info, cache->flags, size, bytes_used,
+	trace_btrfs_add_block_group(fs_info, cache, 1);
+	ret = update_space_info(fs_info, cache->flags, size, bytes_used,
 				cache->bytes_super, &cache->space_info);
 	if (ret) {
 		btrfs_remove_free_space_cache(cache);
-		spin_lock(&root->fs_info->block_group_cache_lock);
+		spin_lock(&fs_info->block_group_cache_lock);
 		rb_erase(&cache->cache_node,
-			 &root->fs_info->block_group_cache_tree);
+			 &fs_info->block_group_cache_tree);
 		RB_CLEAR_NODE(&cache->cache_node);
-		spin_unlock(&root->fs_info->block_group_cache_lock);
+		spin_unlock(&fs_info->block_group_cache_lock);
 		btrfs_put_block_group(cache);
 		return ret;
 	}
-	update_global_block_rsv(root->fs_info);
+	update_global_block_rsv(fs_info);
 
 	__link_block_group(cache->space_info, cache);
 
 	list_add_tail(&cache->bg_list, &trans->new_bgs);
 
-	set_avail_alloc_bits(extent_root->fs_info, type);
+	set_avail_alloc_bits(fs_info, type);
 	return 0;
 }
 
@@ -10281,7 +10316,7 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
 	struct btrfs_path *path;
 	struct btrfs_block_group_cache *block_group;
 	struct btrfs_free_cluster *cluster;
-	struct btrfs_root *tree_root = root->fs_info->tree_root;
+	struct btrfs_root *tree_root = fs_info->tree_root;
 	struct btrfs_key key;
 	struct inode *inode;
 	struct kobject *kobj = NULL;
@@ -10311,7 +10346,7 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
 		factor = 1;
 
 	/* make sure this block group isn't part of an allocation cluster */
-	cluster = &root->fs_info->data_alloc_cluster;
+	cluster = &fs_info->data_alloc_cluster;
 	spin_lock(&cluster->refill_lock);
 	btrfs_return_cluster_to_free_space(block_group, cluster);
 	spin_unlock(&cluster->refill_lock);
@@ -10320,7 +10355,7 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
 	 * make sure this block group isn't part of a metadata
 	 * allocation cluster
 	 */
-	cluster = &root->fs_info->meta_alloc_cluster;
+	cluster = &fs_info->meta_alloc_cluster;
 	spin_lock(&cluster->refill_lock);
 	btrfs_return_cluster_to_free_space(block_group, cluster);
 	spin_unlock(&cluster->refill_lock);
@@ -10400,14 +10435,14 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
 		btrfs_release_path(path);
 	}
 
-	spin_lock(&root->fs_info->block_group_cache_lock);
+	spin_lock(&fs_info->block_group_cache_lock);
 	rb_erase(&block_group->cache_node,
-		 &root->fs_info->block_group_cache_tree);
+		 &fs_info->block_group_cache_tree);
 	RB_CLEAR_NODE(&block_group->cache_node);
 
-	if (root->fs_info->first_logical_byte == block_group->key.objectid)
-		root->fs_info->first_logical_byte = (u64)-1;
-	spin_unlock(&root->fs_info->block_group_cache_lock);
+	if (fs_info->first_logical_byte == block_group->key.objectid)
+		fs_info->first_logical_byte = (u64)-1;
+	spin_unlock(&fs_info->block_group_cache_lock);
 
 	down_write(&block_group->space_info->groups_sem);
 	/*
@@ -10418,7 +10453,7 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
 	if (list_empty(&block_group->space_info->block_groups[index])) {
 		kobj = block_group->space_info->block_group_kobjs[index];
 		block_group->space_info->block_group_kobjs[index] = NULL;
-		clear_avail_alloc_bits(root->fs_info, block_group->flags);
+		clear_avail_alloc_bits(fs_info, block_group->flags);
 	}
 	up_write(&block_group->space_info->groups_sem);
 	if (kobj) {
@@ -10431,12 +10466,12 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
 	if (block_group->cached == BTRFS_CACHE_STARTED)
 		wait_block_group_cache_done(block_group);
 	if (block_group->has_caching_ctl) {
-		down_write(&root->fs_info->commit_root_sem);
+		down_write(&fs_info->commit_root_sem);
 		if (!caching_ctl) {
 			struct btrfs_caching_control *ctl;
 
 			list_for_each_entry(ctl,
-				    &root->fs_info->caching_block_groups, list)
+				    &fs_info->caching_block_groups, list)
 				if (ctl->block_group == block_group) {
 					caching_ctl = ctl;
 					atomic_inc(&caching_ctl->count);
@@ -10445,7 +10480,7 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
 		}
 		if (caching_ctl)
 			list_del_init(&caching_ctl->list);
-		up_write(&root->fs_info->commit_root_sem);
+		up_write(&fs_info->commit_root_sem);
 		if (caching_ctl) {
 			/* Once for the caching bgs list and once for us. */
 			put_caching_control(caching_ctl);
@@ -10466,7 +10501,7 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
 	spin_lock(&block_group->space_info->lock);
 	list_del_init(&block_group->ro_list);
 
-	if (btrfs_test_opt(root->fs_info, ENOSPC_DEBUG)) {
+	if (btrfs_test_opt(fs_info, ENOSPC_DEBUG)) {
 		WARN_ON(block_group->space_info->total_bytes
 			< block_group->key.offset);
 		WARN_ON(block_group->space_info->bytes_readonly
@@ -10482,7 +10517,7 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
 
 	memcpy(&key, &block_group->key, sizeof(key));
 
-	lock_chunks(root->fs_info);
+	lock_chunks(fs_info);
 	if (!list_empty(&em->list)) {
 		/* We're in the transaction->pending_chunks list. */
 		free_extent_map(em);
@@ -10530,14 +10565,14 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
 		 * sees the em, either in the pending_chunks list or in the
 		 * pinned_chunks list.
 		 */
-		list_move_tail(&em->list, &root->fs_info->pinned_chunks);
+		list_move_tail(&em->list, &fs_info->pinned_chunks);
 	}
 	spin_unlock(&block_group->lock);
 
 	if (remove_em) {
 		struct extent_map_tree *em_tree;
 
-		em_tree = &root->fs_info->mapping_tree.map_tree;
+		em_tree = &fs_info->mapping_tree.map_tree;
 		write_lock(&em_tree->lock);
 		/*
 		 * The em might be in the pending_chunks list, so make sure the
@@ -10550,9 +10585,9 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
 		free_extent_map(em);
 	}
 
-	unlock_chunks(root->fs_info);
+	unlock_chunks(fs_info);
 
-	ret = remove_block_group_free_space(trans, root->fs_info, block_group);
+	ret = remove_block_group_free_space(trans, fs_info, block_group);
 	if (ret)
 		goto out;
 
@@ -10734,7 +10769,7 @@ void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info)
 		spin_unlock(&space_info->lock);
 
 		/* DISCARD can flip during remount */
-		trimming = btrfs_test_opt(root->fs_info, DISCARD);
+		trimming = btrfs_test_opt(fs_info, DISCARD);
 
 		/* Implicit trim during transaction commit. */
 		if (trimming)
@@ -10970,8 +11005,8 @@ int btrfs_trim_fs(struct btrfs_root *root, struct fstrim_range *range)
 		cache = next_block_group(fs_info->tree_root, cache);
 	}
 
-	mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
-	devices = &root->fs_info->fs_devices->alloc_list;
+	mutex_lock(&fs_info->fs_devices->device_list_mutex);
+	devices = &fs_info->fs_devices->alloc_list;
 	list_for_each_entry(device, devices, dev_alloc_list) {
 		ret = btrfs_trim_free_extents(device, range->minlen,
 					      &group_trimmed);
@@ -10980,7 +11015,7 @@ int btrfs_trim_fs(struct btrfs_root *root, struct fstrim_range *range)
 
 		trimmed += group_trimmed;
 	}
-	mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
+	mutex_unlock(&fs_info->fs_devices->device_list_mutex);
 
 	range->len = trimmed;
 	return ret;