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>

33 files changed, 2251 insertions, 2016 deletions

diff --git a/fs/btrfs/check-integrity.c b/fs/btrfs/check-integrity.c
index a6243ccd9800..137883cce13c 100644
--- a/fs/btrfs/check-integrity.c
+++ b/fs/btrfs/check-integrity.c
@@ -646,11 +646,12 @@ static struct btrfsic_dev_state *btrfsic_dev_state_hashtable_lookup(
 static int btrfsic_process_superblock(struct btrfsic_state *state,
 				      struct btrfs_fs_devices *fs_devices)
 {
-	int ret = 0;
+	struct btrfs_fs_info *fs_info = state->fs_info;
 	struct btrfs_super_block *selected_super;
 	struct list_head *dev_head = &fs_devices->devices;
 	struct btrfs_device *device;
 	struct btrfsic_dev_state *selected_dev_state = NULL;
+	int ret = 0;
 	int pass;
 
 	BUG_ON(NULL == state);
@@ -716,9 +717,8 @@ static int btrfsic_process_superblock(struct btrfsic_state *state,
 			break;
 		}
 
-		num_copies =
-		    btrfs_num_copies(state->fs_info,
-				     next_bytenr, state->metablock_size);
+		num_copies = btrfs_num_copies(fs_info, next_bytenr,
+					      state->metablock_size);
 		if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES)
 			pr_info("num_copies(log_bytenr=%llu) = %d\n",
 			       next_bytenr, num_copies);
@@ -783,6 +783,7 @@ static int btrfsic_process_superblock_dev_mirror(
 		struct btrfsic_dev_state **selected_dev_state,
 		struct btrfs_super_block *selected_super)
 {
+	struct btrfs_fs_info *fs_info = state->fs_info;
 	struct btrfs_super_block *super_tmp;
 	u64 dev_bytenr;
 	struct buffer_head *bh;
@@ -832,7 +833,7 @@ static int btrfsic_process_superblock_dev_mirror(
 		superblock_tmp->never_written = 0;
 		superblock_tmp->mirror_num = 1 + superblock_mirror_num;
 		if (state->print_mask & BTRFSIC_PRINT_MASK_SUPERBLOCK_WRITE)
-			btrfs_info_in_rcu(device->fs_info,
+			btrfs_info_in_rcu(fs_info,
 				"new initial S-block (bdev %p, %s) @%llu (%s/%llu/%d)",
 				     superblock_bdev,
 				     rcu_str_deref(device->name), dev_bytenr,
@@ -887,9 +888,8 @@ static int btrfsic_process_superblock_dev_mirror(
 			break;
 		}
 
-		num_copies =
-		    btrfs_num_copies(state->fs_info,
-				     next_bytenr, state->metablock_size);
+		num_copies = btrfs_num_copies(fs_info, next_bytenr,
+					      state->metablock_size);
 		if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES)
 			pr_info("num_copies(log_bytenr=%llu) = %d\n",
 			       next_bytenr, num_copies);
@@ -1254,6 +1254,7 @@ static int btrfsic_create_link_to_next_block(
 		struct btrfs_disk_key *disk_key,
 		u64 parent_generation)
 {
+	struct btrfs_fs_info *fs_info = state->fs_info;
 	struct btrfsic_block *next_block = NULL;
 	int ret;
 	struct btrfsic_block_link *l;
@@ -1262,9 +1263,8 @@ static int btrfsic_create_link_to_next_block(
 
 	*next_blockp = NULL;
 	if (0 == *num_copiesp) {
-		*num_copiesp =
-		    btrfs_num_copies(state->fs_info,
-				     next_bytenr, state->metablock_size);
+		*num_copiesp = btrfs_num_copies(fs_info, next_bytenr,
+						state->metablock_size);
 		if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES)
 			pr_info("num_copies(log_bytenr=%llu) = %d\n",
 			       next_bytenr, *num_copiesp);
@@ -1390,13 +1390,14 @@ static int btrfsic_handle_extent_data(
 		struct btrfsic_block_data_ctx *block_ctx,
 		u32 item_offset, int force_iodone_flag)
 {
-	int ret;
+	struct btrfs_fs_info *fs_info = state->fs_info;
 	struct btrfs_file_extent_item file_extent_item;
 	u64 file_extent_item_offset;
 	u64 next_bytenr;
 	u64 num_bytes;
 	u64 generation;
 	struct btrfsic_block_link *l;
+	int ret;
 
 	file_extent_item_offset = offsetof(struct btrfs_leaf, items) +
 				  item_offset;
@@ -1456,9 +1457,8 @@ static int btrfsic_handle_extent_data(
 		else
 			chunk_len = num_bytes;
 
-		num_copies =
-		    btrfs_num_copies(state->fs_info,
-				     next_bytenr, state->datablock_size);
+		num_copies = btrfs_num_copies(fs_info, next_bytenr,
+					      state->datablock_size);
 		if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES)
 			pr_info("num_copies(log_bytenr=%llu) = %d\n",
 			       next_bytenr, num_copies);
@@ -1533,13 +1533,14 @@ static int btrfsic_map_block(struct btrfsic_state *state, u64 bytenr, u32 len,
 			     struct btrfsic_block_data_ctx *block_ctx_out,
 			     int mirror_num)
 {
+	struct btrfs_fs_info *fs_info = state->fs_info;
 	int ret;
 	u64 length;
 	struct btrfs_bio *multi = NULL;
 	struct btrfs_device *device;
 
 	length = len;
-	ret = btrfs_map_block(state->fs_info, BTRFS_MAP_READ,
+	ret = btrfs_map_block(fs_info, BTRFS_MAP_READ,
 			      bytenr, &length, &multi, mirror_num);
 
 	if (ret) {
@@ -1731,6 +1732,7 @@ static void btrfsic_dump_database(struct btrfsic_state *state)
 static int btrfsic_test_for_metadata(struct btrfsic_state *state,
 				     char **datav, unsigned int num_pages)
 {
+	struct btrfs_fs_info *fs_info = state->fs_info;
 	struct btrfs_header *h;
 	u8 csum[BTRFS_CSUM_SIZE];
 	u32 crc = ~(u32)0;
@@ -1741,7 +1743,7 @@ static int btrfsic_test_for_metadata(struct btrfsic_state *state,
 	num_pages = state->metablock_size >> PAGE_SHIFT;
 	h = (struct btrfs_header *)datav[0];
 
-	if (memcmp(h->fsid, state->fs_info->fsid, BTRFS_UUID_SIZE))
+	if (memcmp(h->fsid, fs_info->fsid, BTRFS_UUID_SIZE))
 		return 1;
 
 	for (i = 0; i < num_pages; i++) {
@@ -2202,6 +2204,7 @@ static int btrfsic_process_written_superblock(
 		struct btrfsic_block *const superblock,
 		struct btrfs_super_block *const super_hdr)
 {
+	struct btrfs_fs_info *fs_info = state->fs_info;
 	int pass;
 
 	superblock->generation = btrfs_super_generation(super_hdr);
@@ -2275,9 +2278,8 @@ static int btrfsic_process_written_superblock(
 			break;
 		}
 
-		num_copies =
-		    btrfs_num_copies(state->fs_info,
-				     next_bytenr, BTRFS_SUPER_INFO_SIZE);
+		num_copies = btrfs_num_copies(fs_info, next_bytenr,
+					      BTRFS_SUPER_INFO_SIZE);
 		if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES)
 			pr_info("num_copies(log_bytenr=%llu) = %d\n",
 			       next_bytenr, num_copies);
@@ -2699,14 +2701,14 @@ static void btrfsic_cmp_log_and_dev_bytenr(struct btrfsic_state *state,
 					   struct btrfsic_dev_state *dev_state,
 					   u64 dev_bytenr)
 {
+	struct btrfs_fs_info *fs_info = state->fs_info;
+	struct btrfsic_block_data_ctx block_ctx;
 	int num_copies;
 	int mirror_num;
-	int ret;
-	struct btrfsic_block_data_ctx block_ctx;
 	int match = 0;
+	int ret;
 
-	num_copies = btrfs_num_copies(state->fs_info,
-				      bytenr, state->metablock_size);
+	num_copies = btrfs_num_copies(fs_info, bytenr, state->metablock_size);
 
 	for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) {
 		ret = btrfsic_map_block(state, bytenr, state->metablock_size,
@@ -2909,16 +2911,17 @@ int btrfsic_mount(struct btrfs_root *root,
 	int ret;
 	struct btrfsic_state *state;
 	struct list_head *dev_head = &fs_devices->devices;
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct btrfs_device *device;
 
-	if (root->fs_info->nodesize & ((u64)PAGE_SIZE - 1)) {
+	if (fs_info->nodesize & ((u64)PAGE_SIZE - 1)) {
 		pr_info("btrfsic: cannot handle nodesize %d not being a multiple of PAGE_SIZE %ld!\n",
-		       root->fs_info->nodesize, PAGE_SIZE);
+		       fs_info->nodesize, PAGE_SIZE);
 		return -1;
 	}
-	if (root->fs_info->sectorsize & ((u64)PAGE_SIZE - 1)) {
+	if (fs_info->sectorsize & ((u64)PAGE_SIZE - 1)) {
 		pr_info("btrfsic: cannot handle sectorsize %d not being a multiple of PAGE_SIZE %ld!\n",
-		       root->fs_info->sectorsize, PAGE_SIZE);
+		       fs_info->sectorsize, PAGE_SIZE);
 		return -1;
 	}
 	state = kzalloc(sizeof(*state), GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
@@ -2940,8 +2943,8 @@ int btrfsic_mount(struct btrfs_root *root,
 	state->print_mask = print_mask;
 	state->include_extent_data = including_extent_data;
 	state->csum_size = 0;
-	state->metablock_size = root->fs_info->nodesize;
-	state->datablock_size = root->fs_info->sectorsize;
+	state->metablock_size = fs_info->nodesize;
+	state->datablock_size = fs_info->sectorsize;
 	INIT_LIST_HEAD(&state->all_blocks_list);
 	btrfsic_block_hashtable_init(&state->block_hashtable);
 	btrfsic_block_link_hashtable_init(&state->block_link_hashtable);
diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c
index e4a8c3a085db..750bae4a46da 100644
--- a/fs/btrfs/compression.c
+++ b/fs/btrfs/compression.c
@@ -88,10 +88,11 @@ static int btrfs_decompress_bio(int type, struct page **pages_in,
 static inline int compressed_bio_size(struct btrfs_root *root,
 				      unsigned long disk_size)
 {
-	u16 csum_size = btrfs_super_csum_size(root->fs_info->super_copy);
+	struct btrfs_fs_info *fs_info = root->fs_info;
+	u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
 
 	return sizeof(struct compressed_bio) +
-		(DIV_ROUND_UP(disk_size, root->fs_info->sectorsize)) * csum_size;
+		(DIV_ROUND_UP(disk_size, fs_info->sectorsize)) * csum_size;
 }
 
 static struct bio *compressed_bio_alloc(struct block_device *bdev,
@@ -328,6 +329,7 @@ int btrfs_submit_compressed_write(struct inode *inode, u64 start,
 				 struct page **compressed_pages,
 				 unsigned long nr_pages)
 {
+	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
 	struct bio *bio = NULL;
 	struct btrfs_root *root = BTRFS_I(inode)->root;
 	struct compressed_bio *cb;
@@ -355,7 +357,7 @@ int btrfs_submit_compressed_write(struct inode *inode, u64 start,
 	cb->orig_bio = NULL;
 	cb->nr_pages = nr_pages;
 
-	bdev = BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
+	bdev = fs_info->fs_devices->latest_bdev;
 
 	bio = compressed_bio_alloc(bdev, first_byte, GFP_NOFS);
 	if (!bio) {
@@ -391,8 +393,8 @@ int btrfs_submit_compressed_write(struct inode *inode, u64 start,
 			 * freed before we're done setting it up
 			 */
 			atomic_inc(&cb->pending_bios);
-			ret = btrfs_bio_wq_end_io(root->fs_info, bio,
-					BTRFS_WQ_ENDIO_DATA);
+			ret = btrfs_bio_wq_end_io(fs_info, bio,
+						  BTRFS_WQ_ENDIO_DATA);
 			BUG_ON(ret); /* -ENOMEM */
 
 			if (!skip_sum) {
@@ -417,7 +419,7 @@ int btrfs_submit_compressed_write(struct inode *inode, u64 start,
 			bio_add_page(bio, page, PAGE_SIZE, 0);
 		}
 		if (bytes_left < PAGE_SIZE) {
-			btrfs_info(BTRFS_I(inode)->root->fs_info,
+			btrfs_info(fs_info,
 					"bytes left %lu compress len %lu nr %lu",
 			       bytes_left, cb->compressed_len, cb->nr_pages);
 		}
@@ -427,7 +429,7 @@ int btrfs_submit_compressed_write(struct inode *inode, u64 start,
 	}
 	bio_get(bio);
 
-	ret = btrfs_bio_wq_end_io(root->fs_info, bio, BTRFS_WQ_ENDIO_DATA);
+	ret = btrfs_bio_wq_end_io(fs_info, bio, BTRFS_WQ_ENDIO_DATA);
 	BUG_ON(ret); /* -ENOMEM */
 
 	if (!skip_sum) {
@@ -575,6 +577,7 @@ next:
 int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
 				 int mirror_num, unsigned long bio_flags)
 {
+	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
 	struct extent_io_tree *tree;
 	struct extent_map_tree *em_tree;
 	struct compressed_bio *cb;
@@ -634,7 +637,7 @@ int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
 	if (!cb->compressed_pages)
 		goto fail1;
 
-	bdev = BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
+	bdev = fs_info->fs_devices->latest_bdev;
 
 	for (pg_index = 0; pg_index < nr_pages; pg_index++) {
 		cb->compressed_pages[pg_index] = alloc_page(GFP_NOFS |
@@ -678,8 +681,8 @@ int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
 		    PAGE_SIZE) {
 			bio_get(comp_bio);
 
-			ret = btrfs_bio_wq_end_io(root->fs_info, comp_bio,
-					BTRFS_WQ_ENDIO_DATA);
+			ret = btrfs_bio_wq_end_io(fs_info, comp_bio,
+						  BTRFS_WQ_ENDIO_DATA);
 			BUG_ON(ret); /* -ENOMEM */
 
 			/*
@@ -696,7 +699,7 @@ int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
 				BUG_ON(ret); /* -ENOMEM */
 			}
 			sums += DIV_ROUND_UP(comp_bio->bi_iter.bi_size,
-					     root->fs_info->sectorsize);
+					     fs_info->sectorsize);
 
 			ret = btrfs_map_bio(root, comp_bio, mirror_num, 0);
 			if (ret) {
@@ -719,8 +722,7 @@ int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
 	}
 	bio_get(comp_bio);
 
-	ret = btrfs_bio_wq_end_io(root->fs_info, comp_bio,
-			BTRFS_WQ_ENDIO_DATA);
+	ret = btrfs_bio_wq_end_io(fs_info, comp_bio, BTRFS_WQ_ENDIO_DATA);
 	BUG_ON(ret); /* -ENOMEM */
 
 	if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) {
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 431b150a823a..b29c8d82e741 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -212,21 +212,23 @@ static struct extent_buffer *btrfs_read_lock_root_node(struct btrfs_root *root)
  */
 static void add_root_to_dirty_list(struct btrfs_root *root)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
+
 	if (test_bit(BTRFS_ROOT_DIRTY, &root->state) ||
 	    !test_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state))
 		return;
 
-	spin_lock(&root->fs_info->trans_lock);
+	spin_lock(&fs_info->trans_lock);
 	if (!test_and_set_bit(BTRFS_ROOT_DIRTY, &root->state)) {
 		/* Want the extent tree to be the last on the list */
 		if (root->objectid == BTRFS_EXTENT_TREE_OBJECTID)
 			list_move_tail(&root->dirty_list,
-				       &root->fs_info->dirty_cowonly_roots);
+				       &fs_info->dirty_cowonly_roots);
 		else
 			list_move(&root->dirty_list,
-				  &root->fs_info->dirty_cowonly_roots);
+				  &fs_info->dirty_cowonly_roots);
 	}
-	spin_unlock(&root->fs_info->trans_lock);
+	spin_unlock(&fs_info->trans_lock);
 }
 
 /*
@@ -239,13 +241,14 @@ int btrfs_copy_root(struct btrfs_trans_handle *trans,
 		      struct extent_buffer *buf,
 		      struct extent_buffer **cow_ret, u64 new_root_objectid)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct extent_buffer *cow;
 	int ret = 0;
 	int level;
 	struct btrfs_disk_key disk_key;
 
 	WARN_ON(test_bit(BTRFS_ROOT_REF_COWS, &root->state) &&
-		trans->transid != root->fs_info->running_transaction->transid);
+		trans->transid != fs_info->running_transaction->transid);
 	WARN_ON(test_bit(BTRFS_ROOT_REF_COWS, &root->state) &&
 		trans->transid != root->last_trans);
 
@@ -271,7 +274,7 @@ int btrfs_copy_root(struct btrfs_trans_handle *trans,
 	else
 		btrfs_set_header_owner(cow, new_root_objectid);
 
-	write_extent_buffer_fsid(cow, root->fs_info->fsid);
+	write_extent_buffer_fsid(cow, fs_info->fsid);
 
 	WARN_ON(btrfs_header_generation(buf) > trans->transid);
 	if (new_root_objectid == BTRFS_TREE_RELOC_OBJECTID)
@@ -977,6 +980,7 @@ static noinline int update_ref_for_cow(struct btrfs_trans_handle *trans,
 				       struct extent_buffer *cow,
 				       int *last_ref)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	u64 refs;
 	u64 owner;
 	u64 flags;
@@ -1008,7 +1012,7 @@ static noinline int update_ref_for_cow(struct btrfs_trans_handle *trans,
 			return ret;
 		if (refs == 0) {
 			ret = -EROFS;
-			btrfs_handle_fs_error(root->fs_info, ret, NULL);
+			btrfs_handle_fs_error(fs_info, ret, NULL);
 			return ret;
 		}
 	} else {
@@ -1069,7 +1073,7 @@ static noinline int update_ref_for_cow(struct btrfs_trans_handle *trans,
 			ret = btrfs_dec_ref(trans, root, buf, 1);
 			BUG_ON(ret); /* -ENOMEM */
 		}
-		clean_tree_block(trans, root->fs_info, buf);
+		clean_tree_block(trans, fs_info, buf);
 		*last_ref = 1;
 	}
 	return 0;
@@ -1094,6 +1098,7 @@ static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans,
 			     struct extent_buffer **cow_ret,
 			     u64 search_start, u64 empty_size)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct btrfs_disk_key disk_key;
 	struct extent_buffer *cow;
 	int level, ret;
@@ -1107,7 +1112,7 @@ static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans,
 	btrfs_assert_tree_locked(buf);
 
 	WARN_ON(test_bit(BTRFS_ROOT_REF_COWS, &root->state) &&
-		trans->transid != root->fs_info->running_transaction->transid);
+		trans->transid != fs_info->running_transaction->transid);
 	WARN_ON(test_bit(BTRFS_ROOT_REF_COWS, &root->state) &&
 		trans->transid != root->last_trans);
 
@@ -1140,7 +1145,7 @@ static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans,
 	else
 		btrfs_set_header_owner(cow, root->root_key.objectid);
 
-	write_extent_buffer_fsid(cow, root->fs_info->fsid);
+	write_extent_buffer_fsid(cow, fs_info->fsid);
 
 	ret = update_ref_for_cow(trans, root, buf, cow, &last_ref);
 	if (ret) {
@@ -1172,7 +1177,7 @@ static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans,
 		add_root_to_dirty_list(root);
 	} else {
 		WARN_ON(trans->transid != btrfs_header_generation(parent));
-		tree_mod_log_insert_key(root->fs_info, parent, parent_slot,
+		tree_mod_log_insert_key(fs_info, parent, parent_slot,
 					MOD_LOG_KEY_REPLACE, GFP_NOFS);
 		btrfs_set_node_blockptr(parent, parent_slot,
 					cow->start);
@@ -1180,7 +1185,7 @@ static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans,
 					      trans->transid);
 		btrfs_mark_buffer_dirty(parent);
 		if (last_ref) {
-			ret = tree_mod_log_free_eb(root->fs_info, buf);
+			ret = tree_mod_log_free_eb(fs_info, buf);
 			if (ret) {
 				btrfs_abort_transaction(trans, ret);
 				return ret;
@@ -1400,6 +1405,7 @@ tree_mod_log_rewind(struct btrfs_fs_info *fs_info, struct btrfs_path *path,
 static inline struct extent_buffer *
 get_old_root(struct btrfs_root *root, u64 time_seq)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct tree_mod_elem *tm;
 	struct extent_buffer *eb = NULL;
 	struct extent_buffer *eb_root;
@@ -1409,7 +1415,7 @@ get_old_root(struct btrfs_root *root, u64 time_seq)
 	u64 logical;
 
 	eb_root = btrfs_read_lock_root_node(root);
-	tm = __tree_mod_log_oldest_root(root->fs_info, eb_root, time_seq);
+	tm = __tree_mod_log_oldest_root(fs_info, eb_root, time_seq);
 	if (!tm)
 		return eb_root;
 
@@ -1421,7 +1427,7 @@ get_old_root(struct btrfs_root *root, u64 time_seq)
 		logical = eb_root->start;
 	}
 
-	tm = tree_mod_log_search(root->fs_info, logical, time_seq);
+	tm = tree_mod_log_search(fs_info, logical, time_seq);
 	if (old_root && tm && tm->op != MOD_LOG_KEY_REMOVE_WHILE_FREEING) {
 		btrfs_tree_read_unlock(eb_root);
 		free_extent_buffer(eb_root);
@@ -1429,8 +1435,9 @@ get_old_root(struct btrfs_root *root, u64 time_seq)
 		if (WARN_ON(IS_ERR(old) || !extent_buffer_uptodate(old))) {
 			if (!IS_ERR(old))
 				free_extent_buffer(old);
-			btrfs_warn(root->fs_info,
-				"failed to read tree block %llu from get_old_root", logical);
+			btrfs_warn(fs_info,
+				   "failed to read tree block %llu from get_old_root",
+				   logical);
 		} else {
 			eb = btrfs_clone_extent_buffer(old);
 			free_extent_buffer(old);
@@ -1438,7 +1445,7 @@ get_old_root(struct btrfs_root *root, u64 time_seq)
 	} else if (old_root) {
 		btrfs_tree_read_unlock(eb_root);
 		free_extent_buffer(eb_root);
-		eb = alloc_dummy_extent_buffer(root->fs_info, logical);
+		eb = alloc_dummy_extent_buffer(fs_info, logical);
 	} else {
 		btrfs_set_lock_blocking_rw(eb_root, BTRFS_READ_LOCK);
 		eb = btrfs_clone_extent_buffer(eb_root);
@@ -1458,10 +1465,10 @@ get_old_root(struct btrfs_root *root, u64 time_seq)
 		btrfs_set_header_generation(eb, old_generation);
 	}
 	if (tm)
-		__tree_mod_log_rewind(root->fs_info, eb, time_seq, tm);
+		__tree_mod_log_rewind(fs_info, eb, time_seq, tm);
 	else
 		WARN_ON(btrfs_header_level(eb) != 0);
-	WARN_ON(btrfs_header_nritems(eb) > BTRFS_NODEPTRS_PER_BLOCK(root->fs_info));
+	WARN_ON(btrfs_header_nritems(eb) > BTRFS_NODEPTRS_PER_BLOCK(fs_info));
 
 	return eb;
 }
@@ -1523,17 +1530,18 @@ noinline int btrfs_cow_block(struct btrfs_trans_handle *trans,
 		    struct extent_buffer *parent, int parent_slot,
 		    struct extent_buffer **cow_ret)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	u64 search_start;
 	int ret;
 
-	if (trans->transaction != root->fs_info->running_transaction)
+	if (trans->transaction != fs_info->running_transaction)
 		WARN(1, KERN_CRIT "trans %llu running %llu\n",
 		       trans->transid,
-		       root->fs_info->running_transaction->transid);
+		       fs_info->running_transaction->transid);
 
-	if (trans->transid != root->fs_info->generation)
+	if (trans->transid != fs_info->generation)
 		WARN(1, KERN_CRIT "trans %llu running %llu\n",
-		       trans->transid, root->fs_info->generation);
+		       trans->transid, fs_info->generation);
 
 	if (!should_cow_block(trans, root, buf)) {
 		trans->dirty = true;
@@ -1610,6 +1618,7 @@ int btrfs_realloc_node(struct btrfs_trans_handle *trans,
 		       int start_slot, u64 *last_ret,
 		       struct btrfs_key *progress)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct extent_buffer *cur;
 	u64 blocknr;
 	u64 gen;
@@ -1628,11 +1637,11 @@ int btrfs_realloc_node(struct btrfs_trans_handle *trans,
 
 	parent_level = btrfs_header_level(parent);
 
-	WARN_ON(trans->transaction != root->fs_info->running_transaction);
-	WARN_ON(trans->transid != root->fs_info->generation);
+	WARN_ON(trans->transaction != fs_info->running_transaction);
+	WARN_ON(trans->transid != fs_info->generation);
 
 	parent_nritems = btrfs_header_nritems(parent);
-	blocksize = root->fs_info->nodesize;
+	blocksize = fs_info->nodesize;
 	end_slot = parent_nritems - 1;
 
 	if (parent_nritems <= 1)
@@ -1666,7 +1675,7 @@ int btrfs_realloc_node(struct btrfs_trans_handle *trans,
 			continue;
 		}
 
-		cur = find_extent_buffer(root->fs_info, blocknr);
+		cur = find_extent_buffer(fs_info, blocknr);
 		if (cur)
 			uptodate = btrfs_buffer_uptodate(cur, gen, 0);
 		else
@@ -1711,7 +1720,6 @@ int btrfs_realloc_node(struct btrfs_trans_handle *trans,
 	return err;
 }
 
-
 /*
  * search for key in the extent_buffer.  The items start at offset p,
  * and they are item_size apart.  There are 'max' items in p.
@@ -1865,6 +1873,7 @@ static noinline int balance_level(struct btrfs_trans_handle *trans,
 			 struct btrfs_root *root,
 			 struct btrfs_path *path, int level)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct extent_buffer *right = NULL;
 	struct extent_buffer *mid;
 	struct extent_buffer *left = NULL;
@@ -1905,7 +1914,7 @@ static noinline int balance_level(struct btrfs_trans_handle *trans,
 		child = read_node_slot(root, mid, 0);
 		if (IS_ERR(child)) {
 			ret = PTR_ERR(child);
-			btrfs_handle_fs_error(root->fs_info, ret, NULL);
+			btrfs_handle_fs_error(fs_info, ret, NULL);
 			goto enospc;
 		}
 
@@ -1926,7 +1935,7 @@ static noinline int balance_level(struct btrfs_trans_handle *trans,
 
 		path->locks[level] = 0;
 		path->nodes[level] = NULL;
-		clean_tree_block(trans, root->fs_info, mid);
+		clean_tree_block(trans, fs_info, mid);
 		btrfs_tree_unlock(mid);
 		/* once for the path */
 		free_extent_buffer(mid);
@@ -1938,7 +1947,7 @@ static noinline int balance_level(struct btrfs_trans_handle *trans,
 		return 0;
 	}
 	if (btrfs_header_nritems(mid) >
-	    BTRFS_NODEPTRS_PER_BLOCK(root->fs_info) / 4)
+	    BTRFS_NODEPTRS_PER_BLOCK(fs_info) / 4)
 		return 0;
 
 	left = read_node_slot(root, parent, pslot - 1);
@@ -1987,7 +1996,7 @@ static noinline int balance_level(struct btrfs_trans_handle *trans,
 		if (wret < 0 && wret != -ENOSPC)
 			ret = wret;
 		if (btrfs_header_nritems(right) == 0) {
-			clean_tree_block(trans, root->fs_info, right);
+			clean_tree_block(trans, fs_info, right);
 			btrfs_tree_unlock(right);
 			del_ptr(root, path, level + 1, pslot + 1);
 			root_sub_used(root, right->len);
@@ -1997,7 +2006,7 @@ static noinline int balance_level(struct btrfs_trans_handle *trans,
 		} else {
 			struct btrfs_disk_key right_key;
 			btrfs_node_key(right, &right_key, 0);
-			tree_mod_log_set_node_key(root->fs_info, parent,
+			tree_mod_log_set_node_key(fs_info, parent,
 						  pslot + 1, 0);
 			btrfs_set_node_key(parent, &right_key, pslot + 1);
 			btrfs_mark_buffer_dirty(parent);
@@ -2015,7 +2024,7 @@ static noinline int balance_level(struct btrfs_trans_handle *trans,
 		 */
 		if (!left) {
 			ret = -EROFS;
-			btrfs_handle_fs_error(root->fs_info, ret, NULL);
+			btrfs_handle_fs_error(fs_info, ret, NULL);
 			goto enospc;
 		}
 		wret = balance_node_right(trans, root, mid, left);
@@ -2031,7 +2040,7 @@ static noinline int balance_level(struct btrfs_trans_handle *trans,
 		BUG_ON(wret == 1);
 	}
 	if (btrfs_header_nritems(mid) == 0) {
-		clean_tree_block(trans, root->fs_info, mid);
+		clean_tree_block(trans, fs_info, mid);
 		btrfs_tree_unlock(mid);
 		del_ptr(root, path, level + 1, pslot);
 		root_sub_used(root, mid->len);
@@ -2042,8 +2051,7 @@ static noinline int balance_level(struct btrfs_trans_handle *trans,
 		/* update the parent key to reflect our changes */
 		struct btrfs_disk_key mid_key;
 		btrfs_node_key(mid, &mid_key, 0);
-		tree_mod_log_set_node_key(root->fs_info, parent,
-					  pslot, 0);
+		tree_mod_log_set_node_key(fs_info, parent, pslot, 0);
 		btrfs_set_node_key(parent, &mid_key, pslot);
 		btrfs_mark_buffer_dirty(parent);
 	}
@@ -2090,6 +2098,7 @@ static noinline int push_nodes_for_insert(struct btrfs_trans_handle *trans,
 					  struct btrfs_root *root,
 					  struct btrfs_path *path, int level)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct extent_buffer *right = NULL;
 	struct extent_buffer *mid;
 	struct extent_buffer *left = NULL;
@@ -2125,7 +2134,7 @@ static noinline int push_nodes_for_insert(struct btrfs_trans_handle *trans,
 		btrfs_set_lock_blocking(left);
 
 		left_nr = btrfs_header_nritems(left);
-		if (left_nr >= BTRFS_NODEPTRS_PER_BLOCK(root->fs_info) - 1) {
+		if (left_nr >= BTRFS_NODEPTRS_PER_BLOCK(fs_info) - 1) {
 			wret = 1;
 		} else {
 			ret = btrfs_cow_block(trans, root, left, parent,
@@ -2143,8 +2152,7 @@ static noinline int push_nodes_for_insert(struct btrfs_trans_handle *trans,
 			struct btrfs_disk_key disk_key;
 			orig_slot += left_nr;
 			btrfs_node_key(mid, &disk_key, 0);
-			tree_mod_log_set_node_key(root->fs_info, parent,
-						  pslot, 0);
+			tree_mod_log_set_node_key(fs_info, parent, pslot, 0);
 			btrfs_set_node_key(parent, &disk_key, pslot);
 			btrfs_mark_buffer_dirty(parent);
 			if (btrfs_header_nritems(left) > orig_slot) {
@@ -2179,7 +2187,7 @@ static noinline int push_nodes_for_insert(struct btrfs_trans_handle *trans,
 		btrfs_set_lock_blocking(right);
 
 		right_nr = btrfs_header_nritems(right);
-		if (right_nr >= BTRFS_NODEPTRS_PER_BLOCK(root->fs_info) - 1) {
+		if (right_nr >= BTRFS_NODEPTRS_PER_BLOCK(fs_info) - 1) {
 			wret = 1;
 		} else {
 			ret = btrfs_cow_block(trans, root, right,
@@ -2198,7 +2206,7 @@ static noinline int push_nodes_for_insert(struct btrfs_trans_handle *trans,
 			struct btrfs_disk_key disk_key;
 
 			btrfs_node_key(right, &disk_key, 0);
-			tree_mod_log_set_node_key(root->fs_info, parent,
+			tree_mod_log_set_node_key(fs_info, parent,
 						  pslot + 1, 0);
 			btrfs_set_node_key(parent, &disk_key, pslot + 1);
 			btrfs_mark_buffer_dirty(parent);
@@ -2230,6 +2238,7 @@ static void reada_for_search(struct btrfs_root *root,
 			     struct btrfs_path *path,
 			     int level, int slot, u64 objectid)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct extent_buffer *node;
 	struct btrfs_disk_key disk_key;
 	u32 nritems;
@@ -2250,8 +2259,8 @@ static void reada_for_search(struct btrfs_root *root,
 	node = path->nodes[level];
 
 	search = btrfs_node_blockptr(node, slot);
-	blocksize = root->fs_info->nodesize;
-	eb = find_extent_buffer(root->fs_info, search);
+	blocksize = fs_info->nodesize;
+	eb = find_extent_buffer(fs_info, search);
 	if (eb) {
 		free_extent_buffer(eb);
 		return;
@@ -2292,6 +2301,7 @@ static void reada_for_search(struct btrfs_root *root,
 static noinline void reada_for_balance(struct btrfs_root *root,
 				       struct btrfs_p