ext4: Remove old legacy block allocator

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

fs/ext4/balloc.c

@@ -83,6 +83,7 @@ static int ext4_group_used_meta_blocks(struct super_block *sb,
 	}
 	return used_blocks;
 }
+
 /* Initializes an uninitialized block bitmap if given, and returns the
  * number of blocks free in the group. */
 unsigned ext4_init_block_bitmap(struct super_block *sb, struct buffer_head *bh,
@@ -345,303 +346,6 @@ ext4_read_block_bitmap(struct super_block *sb, ext4_group_t block_group)
 	 */
 	return bh;
 }
-/*
- * The reservation window structure operations
- * --------------------------------------------
- * Operations include:
- * dump, find, add, remove, is_empty, find_next_reservable_window, etc.
- *
- * We use a red-black tree to represent per-filesystem reservation
- * windows.
- *
- */
-
-/**
- * __rsv_window_dump() -- Dump the filesystem block allocation reservation map
- * @rb_root:		root of per-filesystem reservation rb tree
- * @verbose:		verbose mode
- * @fn:			function which wishes to dump the reservation map
- *
- * If verbose is turned on, it will print the whole block reservation
- * windows(start, end).	Otherwise, it will only print out the "bad" windows,
- * those windows that overlap with their immediate neighbors.
- */
-#if 1
-static void __rsv_window_dump(struct rb_root *root, int verbose,
-			      const char *fn)
-{
-	struct rb_node *n;
-	struct ext4_reserve_window_node *rsv, *prev;
-	int bad;
-
-restart:
-	n = rb_first(root);
-	bad = 0;
-	prev = NULL;
-
-	printk(KERN_DEBUG "Block Allocation Reservation "
-	       "Windows Map (%s):\n", fn);
-	while (n) {
-		rsv = rb_entry(n, struct ext4_reserve_window_node, rsv_node);
-		if (verbose)
-			printk(KERN_DEBUG "reservation window 0x%p "
-			       "start:  %llu, end:  %llu\n",
-			       rsv, rsv->rsv_start, rsv->rsv_end);
-		if (rsv->rsv_start && rsv->rsv_start >= rsv->rsv_end) {
-			printk(KERN_DEBUG "Bad reservation %p (start >= end)\n",
-			       rsv);
-			bad = 1;
-		}
-		if (prev && prev->rsv_end >= rsv->rsv_start) {
-			printk(KERN_DEBUG "Bad reservation %p "
-			       "(prev->end >= start)\n", rsv);
-			bad = 1;
-		}
-		if (bad) {
-			if (!verbose) {
-				printk(KERN_DEBUG "Restarting reservation "
-				       "walk in verbose mode\n");
-				verbose = 1;
-				goto restart;
-			}
-		}
-		n = rb_next(n);
-		prev = rsv;
-	}
-	printk(KERN_DEBUG "Window map complete.\n");
-	BUG_ON(bad);
-}
-#define rsv_window_dump(root, verbose) \
-	__rsv_window_dump((root), (verbose), __func__)
-#else
-#define rsv_window_dump(root, verbose) do {} while (0)
-#endif
-
-/**
- * goal_in_my_reservation()
- * @rsv:		inode's reservation window
- * @grp_goal:		given goal block relative to the allocation block group
- * @group:		the current allocation block group
- * @sb:			filesystem super block
- *
- * Test if the given goal block (group relative) is within the file's
- * own block reservation window range.
- *
- * If the reservation window is outside the goal allocation group, return 0;
- * grp_goal (given goal block) could be -1, which means no specific
- * goal block. In this case, always return 1.
- * If the goal block is within the reservation window, return 1;
- * otherwise, return 0;
- */
-static int
-goal_in_my_reservation(struct ext4_reserve_window *rsv, ext4_grpblk_t grp_goal,
-			ext4_group_t group, struct super_block *sb)
-{
-	ext4_fsblk_t group_first_block, group_last_block;
-
-	group_first_block = ext4_group_first_block_no(sb, group);
-	group_last_block = group_first_block + (EXT4_BLOCKS_PER_GROUP(sb) - 1);
-
-	if ((rsv->_rsv_start > group_last_block) ||
-	    (rsv->_rsv_end < group_first_block))
-		return 0;
-	if ((grp_goal >= 0) && ((grp_goal + group_first_block < rsv->_rsv_start)
-		|| (grp_goal + group_first_block > rsv->_rsv_end)))
-		return 0;
-	return 1;
-}
-
-/**
- * search_reserve_window()
- * @rb_root:		root of reservation tree
- * @goal:		target allocation block
- *
- * Find the reserved window which includes the goal, or the previous one
- * if the goal is not in any window.
- * Returns NULL if there are no windows or if all windows start after the goal.
- */
-static struct ext4_reserve_window_node *
-search_reserve_window(struct rb_root *root, ext4_fsblk_t goal)
-{
-	struct rb_node *n = root->rb_node;
-	struct ext4_reserve_window_node *rsv;
-
-	if (!n)
-		return NULL;
-
-	do {
-		rsv = rb_entry(n, struct ext4_reserve_window_node, rsv_node);
-
-		if (goal < rsv->rsv_start)
-			n = n->rb_left;
-		else if (goal > rsv->rsv_end)
-			n = n->rb_right;
-		else
-			return rsv;
-	} while (n);
-	/*
-	 * We've fallen off the end of the tree: the goal wasn't inside
-	 * any particular node.  OK, the previous node must be to one
-	 * side of the interval containing the goal.  If it's the RHS,
-	 * we need to back up one.
-	 */
-	if (rsv->rsv_start > goal) {
-		n = rb_prev(&rsv->rsv_node);
-		rsv = rb_entry(n, struct ext4_reserve_window_node, rsv_node);
-	}
-	return rsv;
-}
-
-/**
- * ext4_rsv_window_add() -- Insert a window to the block reservation rb tree.
- * @sb:			super block
- * @rsv:		reservation window to add
- *
- * Must be called with rsv_lock hold.
- */
-void ext4_rsv_window_add(struct super_block *sb,
-		    struct ext4_reserve_window_node *rsv)
-{
-	struct rb_root *root = &EXT4_SB(sb)->s_rsv_window_root;
-	struct rb_node *node = &rsv->rsv_node;
-	ext4_fsblk_t start = rsv->rsv_start;
-
-	struct rb_node **p = &root->rb_node;
-	struct rb_node *parent = NULL;
-	struct ext4_reserve_window_node *this;
-
-	while (*p)
-	{
-		parent = *p;
-		this = rb_entry(parent, struct ext4_reserve_window_node, rsv_node);
-
-		if (start < this->rsv_start)
-			p = &(*p)->rb_left;
-		else if (start > this->rsv_end)
-			p = &(*p)->rb_right;
-		else {
-			rsv_window_dump(root, 1);
-			BUG();
-		}
-	}
-
-	rb_link_node(node, parent, p);
-	rb_insert_color(node, root);
-}
-
-/**
- * ext4_rsv_window_remove() -- unlink a window from the reservation rb tree
- * @sb:			super block
- * @rsv:		reservation window to remove
- *
- * Mark the block reservation window as not allocated, and unlink it
- * from the filesystem reservation window rb tree. Must be called with
- * rsv_lock hold.
- */
-static void rsv_window_remove(struct super_block *sb,
-			      struct ext4_reserve_window_node *rsv)
-{
-	rsv->rsv_start = EXT4_RESERVE_WINDOW_NOT_ALLOCATED;
-	rsv->rsv_end = EXT4_RESERVE_WINDOW_NOT_ALLOCATED;
-	rsv->rsv_alloc_hit = 0;
-	rb_erase(&rsv->rsv_node, &EXT4_SB(sb)->s_rsv_window_root);
-}
-
-/*
- * rsv_is_empty() -- Check if the reservation window is allocated.
- * @rsv:		given reservation window to check
- *
- * returns 1 if the end block is EXT4_RESERVE_WINDOW_NOT_ALLOCATED.
- */
-static inline int rsv_is_empty(struct ext4_reserve_window *rsv)
-{
-	/* a valid reservation end block could not be 0 */
-	return rsv->_rsv_end == EXT4_RESERVE_WINDOW_NOT_ALLOCATED;
-}
-
-/**
- * ext4_init_block_alloc_info()
- * @inode:		file inode structure
- *
- * Allocate and initialize the	reservation window structure, and
- * link the window to the ext4 inode structure at last
- *
- * The reservation window structure is only dynamically allocated
- * and linked to ext4 inode the first time the open file
- * needs a new block. So, before every ext4_new_block(s) call, for
- * regular files, we should check whether the reservation window
- * structure exists or not. In the latter case, this function is called.
- * Fail to do so will result in block reservation being turned off for that
- * open file.
- *
- * This function is called from ext4_get_blocks_handle(), also called
- * when setting the reservation window size through ioctl before the file
- * is open for write (needs block allocation).
- *
- * Needs down_write(i_data_sem) protection prior to call this function.
- */
-void ext4_init_block_alloc_info(struct inode *inode)
-{
-	struct ext4_inode_info *ei = EXT4_I(inode);
-	struct ext4_block_alloc_info *block_i = ei->i_block_alloc_info;
-	struct super_block *sb = inode->i_sb;
-
-	block_i = kmalloc(sizeof(*block_i), GFP_NOFS);
-	if (block_i) {
-		struct ext4_reserve_window_node *rsv = &block_i->rsv_window_node;
-
-		rsv->rsv_start = EXT4_RESERVE_WINDOW_NOT_ALLOCATED;
-		rsv->rsv_end = EXT4_RESERVE_WINDOW_NOT_ALLOCATED;
-
-		/*
-		 * if filesystem is mounted with NORESERVATION, the goal
-		 * reservation window size is set to zero to indicate
-		 * block reservation is off
-		 */
-		if (!test_opt(sb, RESERVATION))
-			rsv->rsv_goal_size = 0;
-		else
-			rsv->rsv_goal_size = EXT4_DEFAULT_RESERVE_BLOCKS;
-		rsv->rsv_alloc_hit = 0;
-		block_i->last_alloc_logical_block = 0;
-		block_i->last_alloc_physical_block = 0;
-	}
-	ei->i_block_alloc_info = block_i;
-}
-
-/**
- * ext4_discard_reservation()
- * @inode:		inode
- *
- * Discard(free) block reservation window on last file close, or truncate
- * or at last iput().
- *
- * It is being called in three cases:
- *	ext4_release_file(): last writer close the file
- *	ext4_clear_inode(): last iput(), when nobody link to this file.
- *	ext4_truncate(): when the block indirect map is about to change.
- *
- */
-void ext4_discard_reservation(struct inode *inode)
-{
-	struct ext4_inode_info *ei = EXT4_I(inode);
-	struct ext4_block_alloc_info *block_i = ei->i_block_alloc_info;
-	struct ext4_reserve_window_node *rsv;
-	spinlock_t *rsv_lock = &EXT4_SB(inode->i_sb)->s_rsv_window_lock;
-
-	ext4_mb_discard_inode_preallocations(inode);
-
-	if (!block_i)
-		return;
-
-	rsv = &block_i->rsv_window_node;
-	if (!rsv_is_empty(&rsv->rsv_window)) {
-		spin_lock(rsv_lock);
-		if (!rsv_is_empty(&rsv->rsv_window))
-			rsv_window_remove(inode->i_sb, rsv);
-		spin_unlock(rsv_lock);
-	}
-}
 
 /**
  * ext4_free_blocks_sb() -- Free given blocks and update quota
@@ -650,6 +354,13 @@ void ext4_discard_reservation(struct inode *inode)
  * @block:			start physcial block to free
  * @count:			number of blocks to free
  * @pdquot_freed_blocks:	pointer to quota
+ *
+ * XXX This function is only used by the on-line resizing code, which
+ * should probably be fixed up to call the mballoc variant.  There
+ * this needs to be cleaned up later; in fact, I'm not convinced this
+ * is 100% correct in the face of the mballoc code.  The online resizing
+ * code needs to be fixed up to more tightly (and correctly) interlock
+ * with the mballoc code.
  */
 void ext4_free_blocks_sb(handle_t *handle, struct super_block *sb,
 			 ext4_fsblk_t block, unsigned long count,
@@ -861,747 +572,13 @@ void ext4_free_blocks(handle_t *handle, struct inode *inode,
 
 	sb = inode->i_sb;
 
-	if (!test_opt(sb, MBALLOC) || !EXT4_SB(sb)->s_group_info)
-		ext4_free_blocks_sb(handle, sb, block, count,
-						&dquot_freed_blocks);
-	else
-		ext4_mb_free_blocks(handle, inode, block, count,
-						metadata, &dquot_freed_blocks);
+	ext4_mb_free_blocks(handle, inode, block, count,
+			    metadata, &dquot_freed_blocks);
 	if (dquot_freed_blocks)
 		DQUOT_FREE_BLOCK(inode, dquot_freed_blocks);
 	return;
 }
 
-/**
- * ext4_test_allocatable()
- * @nr:			given allocation block group
- * @bh:			bufferhead contains the bitmap of the given block group
- *
- * For ext4 allocations, we must not reuse any blocks which are
- * allocated in the bitmap buffer's "last committed data" copy.  This
- * prevents deletes from freeing up the page for reuse until we have
- * committed the delete transaction.
- *
- * If we didn't do this, then deleting something and reallocating it as
- * data would allow the old block to be overwritten before the
- * transaction committed (because we force data to disk before commit).
- * This would lead to corruption if we crashed between overwriting the
- * data and committing the delete.
- *
- * @@@ We may want to make this allocation behaviour conditional on
- * data-writes at some point, and disable it for metadata allocations or
- * sync-data inodes.
- */
-static int ext4_test_allocatable(ext4_grpblk_t nr, struct buffer_head *bh)
-{
-	int ret;
-	struct journal_head *jh = bh2jh(bh);
-
-	if (ext4_test_bit(nr, bh->b_data))
-		return 0;
-
-	jbd_lock_bh_state(bh);
-	if (!jh->b_committed_data)
-		ret = 1;
-	else
-		ret = !ext4_test_bit(nr, jh->b_committed_data);
-	jbd_unlock_bh_state(bh);
-	return ret;
-}
-
-/**
- * bitmap_search_next_usable_block()
- * @start:		the starting block (group relative) of the search
- * @bh:			bufferhead contains the block group bitmap
- * @maxblocks:		the ending block (group relative) of the reservation
- *
- * The bitmap search --- search forward alternately through the actual
- * bitmap on disk and the last-committed copy in journal, until we find a
- * bit free in both bitmaps.
- */
-static ext4_grpblk_t
-bitmap_search_next_usable_block(ext4_grpblk_t start, struct buffer_head *bh,
-					ext4_grpblk_t maxblocks)
-{
-	ext4_grpblk_t next;
-	struct journal_head *jh = bh2jh(bh);
-
-	while (start < maxblocks) {
-		next = ext4_find_next_zero_bit(bh->b_data, maxblocks, start);
-		if (next >= maxblocks)
-			return -1;
-		if (ext4_test_allocatable(next, bh))
-			return next;
-		jbd_lock_bh_state(bh);
-		if (jh->b_committed_data)
-			start = ext4_find_next_zero_bit(jh->b_committed_data,
-							maxblocks, next);
-		jbd_unlock_bh_state(bh);
-	}
-	return -1;
-}
-
-/**
- * find_next_usable_block()
- * @start:		the starting block (group relative) to find next
- *			allocatable block in bitmap.
- * @bh:			bufferhead contains the block group bitmap
- * @maxblocks:		the ending block (group relative) for the search
- *
- * Find an allocatable block in a bitmap.  We honor both the bitmap and
- * its last-committed copy (if that exists), and perform the "most
- * appropriate allocation" algorithm of looking for a free block near
- * the initial goal; then for a free byte somewhere in the bitmap; then
- * for any free bit in the bitmap.
- */
-static ext4_grpblk_t
-find_next_usable_block(ext4_grpblk_t start, struct buffer_head *bh,
-			ext4_grpblk_t maxblocks)
-{
-	ext4_grpblk_t here, next;
-	char *p, *r;
-
-	if (start > 0) {
-		/*
-		 * The goal was occupied; search forward for a free
-		 * block within the next XX blocks.
-		 *
-		 * end_goal is more or less random, but it has to be
-		 * less than EXT4_BLOCKS_PER_GROUP. Aligning up to the
-		 * next 64-bit boundary is simple..
-		 */
-		ext4_grpblk_t end_goal = (start + 63) & ~63;
-		if (end_goal > maxblocks)
-			end_goal = maxblocks;
-		here = ext4_find_next_zero_bit(bh->b_data, end_goal, start);
-		if (here < end_goal && ext4_test_allocatable(here, bh))
-			return here;
-		ext4_debug("Bit not found near goal\n");
-	}
-
-	here = start;
-	if (here < 0)
-		here = 0;
-
-	p = ((char *)bh->b_data) + (here >> 3);
-	r = memscan(p, 0, ((maxblocks + 7) >> 3) - (here >> 3));
-	next = (r - ((char *)bh->b_data)) << 3;
-
-	if (next < maxblocks && next >= start && ext4_test_allocatable(next, bh))
-		return next;
-
-	/*
-	 * The bitmap search --- search forward alternately through the actual
-	 * bitmap and the last-committed copy until we find a bit free in
-	 * both
-	 */
-	here = bitmap_search_next_usable_block(here, bh, maxblocks);
-	return here;
-}
-
-/**
- * claim_block()
- * @block:		the free block (group relative) to allocate
- * @bh:			the bufferhead containts the block group bitmap
- *
- * We think we can allocate this block in this bitmap.  Try to set the bit.
- * If that succeeds then check that nobody has allocated and then freed the
- * block since we saw that is was not marked in b_committed_data.  If it _was_
- * allocated and freed then clear the bit in the bitmap again and return
- * zero (failure).
- */
-static inline int
-claim_block(spinlock_t *lock, ext4_grpblk_t block, struct buffer_head *bh)
-{
-	struct journal_head *jh = bh2jh(bh);
-	int ret;
-
-	if (ext4_set_bit_atomic(lock, block, bh->b_data))
-		return 0;
-	jbd_lock_bh_state(bh);
-	if (jh->b_committed_data && ext4_test_bit(block, jh->b_committed_data)) {
-		ext4_clear_bit_atomic(lock, block, bh->b_data);
-		ret = 0;
-	} else {
-		ret = 1;
-	}
-	jbd_unlock_bh_state(bh);
-	return ret;
-}
-
-/**
- * ext4_try_to_allocate()
- * @sb:			superblock
- * @handle:		handle to this transaction
- * @group:		given allocation block group
- * @bitmap_bh:		bufferhead holds the block bitmap
- * @grp_goal:		given target block within the group
- * @count:		target number of blocks to allocate
- * @my_rsv:		reservation window
- *
- * Attempt to allocate blocks within a give range. Set the range of allocation
- * first, then find the first free bit(s) from the bitmap (within the range),
- * and at last, allocate the blocks by claiming the found free bit as allocated.
- *
- * To set the range of this allocation:
- *	if there is a reservation window, only try to allocate block(s) from the
- *	file's own reservation window;
- *	Otherwise, the allocation range starts from the give goal block, ends at
- *	the block group's last block.
- *
- * If we failed to allocate the desired block then we may end up crossing to a
- * new bitmap.  In that case we must release write access to the old one via
- * ext4_journal_release_buffer(), else we'll run out of credits.
- */
-static ext4_grpblk_t
-ext4_try_to_allocate(struct super_block *sb, handle_t *handle,
-			ext4_group_t group, struct buffer_head *bitmap_bh,
-			ext4_grpblk_t grp_goal, unsigned long *count,
-			struct ext4_reserve_window *my_rsv)
-{
-	ext4_fsblk_t group_first_block;
-	ext4_grpblk_t start, end;
-	unsigned long num = 0;
-
-	/* we do allocation within the reservation window if we have a window */
-	if (my_rsv) {
-		group_first_block = ext4_group_first_block_no(sb, group);
-		if (my_rsv->_rsv_start >= group_first_block)
-			start = my_rsv->_rsv_start - group_first_block;
-		else
-			/* reservation window cross group boundary */
-			start = 0;
-		end = my_rsv->_rsv_end - group_first_block + 1;
-		if (end > EXT4_BLOCKS_PER_GROUP(sb))
-			/* reservation window crosses group boundary */
-			end = EXT4_BLOCKS_PER_GROUP(sb);
-		if ((start <= grp_goal) && (grp_goal < end))
-			start = grp_goal;
-		else
-			grp_goal = -1;
-	} else {
-		if (grp_goal > 0)
-			start = grp_goal;
-		else
-			start = 0;
-		end = EXT4_BLOCKS_PER_GROUP(sb);
-	}
-
-	BUG_ON(start > EXT4_BLOCKS_PER_GROUP(sb));
-
-repeat:
-	if (grp_goal < 0 || !ext4_test_allocatable(grp_goal, bitmap_bh)) {
-		grp_goal = find_next_usable_block(start, bitmap_bh, end);
-		if (grp_goal < 0)
-			goto fail_access;
-		if (!my_rsv) {
-			int i;
-
-			for (i = 0; i < 7 && grp_goal > start &&
-					ext4_test_allocatable(grp_goal - 1,
-								bitmap_bh);
-					i++, grp_goal--)
-				;
-		}
-	}
-	start = grp_goal;
-
-	if (!claim_block(sb_bgl_lock(EXT4_SB(sb), group),
-		grp_goal, bitmap_bh)) {
-		/*
-		 * The block was allocated by another thread, or it was
-		 * allocated and then freed by another thread
-		 */
-		start++;
-		grp_goal++;
-		if (start >= end)
-			goto fail_access;
-		goto repeat;
-	}
-	num++;
-	grp_goal++;
-	while (num < *count && grp_goal < end
-		&& ext4_test_allocatable(grp_goal, bitmap_bh)
-		&& claim_block(sb_bgl_lock(EXT4_SB(sb), group),
-				grp_goal, bitmap_bh)) {
-		num++;
-		grp_goal++;
-	}
-	*count = num;
-	return grp_goal - num;
-fail_access:
-	*count = num;
-	return -1;
-}
-
-/**
- *	find_next_reservable_window():
- *		find a reservable space within the given range.
- *		It does not allocate the reservation window for now:
- *		alloc_new_reservation() will do the work later.
- *
- *	@search_head: the head of the searching list;
- *		This is not necessarily the list head of the whole filesystem
- *
- *		We have both head and start_block to assist the search
- *		for the reservable space. The list starts from head,
- *		but we will shift to the place where start_block is,
- *		then start from there, when looking for a reservable space.
- *
- *	@size: the target new reservation window size
- *
- *	@group_first_block: the first block we consider to start
- *			the real search from
- *
- *	@last_block:
- *		the maximum block number that our goal reservable space
- *		could start from. This is normally the last block in this
- *		group. The search will end when we found the start of next
- *		possible reservable space is out of this boundary.
- *		This could handle the cross boundary reservation window
- *		request.
- *
- *	basically we search from the given range, rather than the whole
- *	reservation double linked list, (start_block, last_block)
- *	to find a free region that is of my size and has not
- *	been reserved.
- *
- */
-static int find_next_reservable_window(
-				struct ext4_reserve_window_node *search_head,
-				struct ext4_reserve_window_node *my_rsv,
-				struct super_block *sb,
-				ext4_fsblk_t start_block,
-				ext4_fsblk_t last_block)
-{
-	struct rb_node *next;
-	struct ext4_reserve_window_node *rsv, *prev;
-	ext4_fsblk_t cur;
-	int size = my_rsv->rsv_goal_size;
-
-	/* TODO: make the start of the reservation window byte-aligned */
-	/* cur = *start_block & ~7;*/
-	cur = start_block;
-	rsv = search_head;
-	if (!rsv)
-		return -1;
-
-	while (1) {
-		if (cur <= rsv->rsv_end)
-			cur = rsv->rsv_end + 1;
-
-		/* TODO?
-		 * in the case we could not find a reservable space
-		 * that is what is expected, during the re-search, we could
-		 * remember what's the largest reservable space we could have
-		 * and return that one.
-		 *
-		 * For now it will fail if we could not find the reservable
-		 * space with expected-size (or more)...
-		 */
-		if (cur > last_block)
-			return -1;		/* fail */
-
-		prev = rsv;
-		next = rb_next(&rsv->rsv_node);
-		rsv = rb_entry(next, struct ext4_reserve_window_node, rsv_node);
-
-		/*
-		 * Reached the last reservation, we can just append to the
-		 * previous one.
-		 */
-		if (!next)
-			break;
-
-		if (cur + size <= rsv->rsv_start) {
-			/*
-			 * Found a reserveable space big enough.  We could
-			 * have a reservation across the group boundary here
-			 */
-			break;
-		}
-	}
-	/*
-	 * we come here either :
-	 * when we reach the end of the whole list,
-	 * and there is empty reservable space after last entry in the list.
-	 * append it to the end of the list.
-	 *
-	 * or we found one reservable space in the middle of the list,
-	 * return the reservation window that we could append to.
-	 * succeed.
-	 */
-
-	if ((prev != my_rsv) && (!rsv_is_empty(&my_rsv->rsv_window)))
-		rsv_window_remove(sb, my_rsv);
-
-	/*
-	 * Let's book the whole avaliable window for now.  We will check the
-	 * disk bitmap later and then, if there are free blocks then we adjust
-	 * the window size if it's larger than requested.
-	 * Otherwise, we will remove this node from the tree next time
-	 * call find_next_reservable_window.
-	 */
-	my_rsv->rsv_start = cur;
-	my_rsv->rsv_end = cur + size - 1;
-	my_rsv->rsv_alloc_hit = 0;
-
-	if (prev != my_rsv)
-		ext4_rsv_window_add(sb, my_rsv);
-
-	return 0;
-}
-
-/**
- *	alloc_new_reservation()--allocate a new reservation window
- *
- *		To make a new reservation, we search part of the filesystem
- *		reservation list (the list that inside the group). We try to
- *		allocate a new reservation window near the allocation goal,
- *		or the beginning of the group, if there is no goal.
- *
- *		We first find a reservable space after the goal, then from
- *		there, we check the bitmap for the first free block after
- *		it. If there is no free block until the end of group, then the
- *		whole group is full, we failed. Otherwise, check if the free
- *		block is inside the expected reservable space, if so, we
- *		succeed.
- *		If the first free block is outside the reservable space, then
- *		start from the first free block, we search for next available
- *		space, and go on.
- *
- *	on succeed, a new reservation will be found and inserted into the list
- *	It contains at least one free block, and it does not overlap with other
- *	reservation windows.
- *
- *	failed: we failed to find a reservation window in this group
- *
- *	@rsv: the reservation
- *
- *	@grp_goal: The goal (group-relative).  It is where the search for a
- *		free reservable space should start from.
- *		if we have a grp_goal(grp_goal >0 ), then start from there,
- *		no grp_goal(grp_goal = -1), we start from the first block
- *		of the group.
- *
- *	@sb: the super block
- *	@group: the group we are trying to allocate in
- *	@bitmap_bh: the block group block bitmap
- *
- */
-static int alloc_new_reservation(struct ext4_reserve_window_node *my_rsv,
-		ext4_grpblk_t grp_goal, struct super_block *sb,
-		ext4_group_t group, struct buffer_head *bitmap_bh)
-{
-	struct ext4_reserve_window_node *search_head;
-	ext4_fsblk_t group_first_block, group_end_block, start_block;
-	ext4_grpblk_t first_free_block;
-	struct rb_root *fs_rsv_root = &EXT4_SB(sb)->s_rsv_window_root;
-	unsigned long size;
-	int ret;
-	spinlock_t *rsv_lock = &EXT4_SB(sb)->s_rsv_window_lock;
-
-	group_first_block = ext4_group_first_block_no(sb, group);
-	group_end_block = group_first_block + (EXT4_BLOCKS_PER_GROUP(sb) - 1);
-
-	if (grp_goal < 0)
-		start_block = group_first_block;
-	else
-		start_block = grp_goal + group_first_block;
-
-	size = my_rsv->rsv_goal_size;
-
-	if (!rsv_is_empty(&my_rsv->rsv_window)) {
-		/*
-		 * if the old reservation is cross group boundary
-		 * and if the goal is inside the old reservation window,
-		 * we will come here when we just failed to allocate from
-		 * the first part of the window. We still have another part
-		 * that belongs to the next group. In this case, there is no
-		 * point to discard our window and try to allocate a new one
-		 * in this group(which will fail). we should
-		 * keep the reservation window, just simply move on.
-		 *
-		 * Maybe we could shift the start block of the reservation
-		 * window to the first block of next group.
-		 */
-
-		if ((my_rsv->rsv_start <= group_end_block) &&
-				(my_rsv->rsv_end > group_end_block) &&
-				(start_block >= my_rsv->rsv_start))
-			return -1;
-
-		if ((my_rsv->rsv_alloc_hit >
-		     (my_rsv->rsv_end - my_rsv->rsv_start + 1) / 2)) {
-			/*
-			 * if the previously allocation hit ratio is
-			 * greater than 1/2, then we double the size of
-			 * the reservation window the next time,
-			 * otherwise we keep the same size window
-			 */
-			size = size * 2;
-			if (size > EXT4_MAX_RESERVE_BLOCKS)
-				size = EXT4_MAX_RESERVE_BLOCKS;
-			my_rsv->rsv_goal_size = size;
-		}
-	}
-
-	spin_lock(rsv_lock);
-	/*
-	 * shift the search start to the window near the goal block
-	 */
-	search_head = search_reserve_window(fs_rsv_root, start_block);
-
-	/*
-	 * find_next_reservable_window() simply finds a reservable window
-	 * inside the given range(start_block, group_end_block).
-	 *
-	 * To make sure the reservation window has a free bit inside it, we
-	 * need to check the bitmap after we found a reservable window.
-	 */
-retry:
-	ret = find_next_reservable_window(search_head, my_rsv, sb,
-						start_block, group_end_block);
-
-	if (ret == -1) {
-		if (!rsv_is_empty(&my_rsv->rsv_window))
-			rsv_window_remove(sb, my_rsv);
-		spin_unlock(rsv_lock);
-		return -1;
-	}
-
-	/*
-	 * On success, find_next_reservable_window() returns the
-	 * reservation window where there is a reservable space after it.
-	 * Before we reserve this reservable space, we need
-	 * to make sure there is at least a free block inside this region.
-	 *
-	 * searching the first free bit on the block bitmap and copy of
-	 * last committed bitmap alternatively, until we found a allocatable
-	 * block. Search start from the start block of the reservable space
-	 * we just found.
-	 */
-	spin_unlock(rsv_lock);
-	first_free_block = bitmap_search_next_usable_block(
-			my_rsv->rsv_start - group_first_block,
-			bitmap_bh, group_end_block - group_first_block + 1);
-
-	if (first_free_block < 0) {
-		/*
-		 * no free block left on the bitmap, no point
-		 * to reserve the space. return failed.
-		 */
-		spin_lock(rsv_lock);
-		if (!rsv_is_empty(&my_rsv->rsv_window))
-			rsv_window_remove(sb, my_rsv);
-		spin_unlock(rsv_lock);
-		return -1;		/* failed */
-	}
-
-	start_block = first_free_block + group_first_block;
-	/*
-	 * check if the first free block is within the
-	 * free space we just reserved
-	 */
-	if (start_block >= my_rsv->rsv_start && start_block <= my_rsv->rsv_end)
-		return 0;		/* success */
-	/*
-	 * if the first free bit we found is out of the reservable space
-	 * continue search for next reservable space,
-	 * start from where the free block is,
-	 * we also shift the list head to where we stopped last time
-	 */
-	search_head = my_rsv;
-	spin_lock(rsv_lock);
-	goto retry;
-}
-
-/**
- * try_to_extend_reservation()
- * @my_rsv:		given reservation window
- * @sb:			super block
- * @size:		the delta to extend
- *
- * Attempt to expand the reservation window large enough to have
- * required number of free blocks
- *
- * Since ext4_try_to_allocate() will always allocate blocks within
- * the reservation window range, if the window size is too small,
- * multiple blocks allocation has to stop at the end of the reservation
- * window. To make this more efficient, given the total number of
- * blocks needed and the current size of the window, we try to
- * expand the reservation window size if necessary on a best-effort
- * basis before ext4_new_blocks() tries to allocate blocks,
- */
-static void try_to_extend_reservation(struct ext4_reserve_window_node *my_rsv,
-			struct super_block *sb, int size)
-{
-	struct ext4_reserve_window_node *next_rsv;
-	struct rb_node *next;
-	spinlock_t *rsv_lock = &EXT4_SB(sb)->s_rsv_window_lock;
-
-	if (!spin_trylock(rsv_lock))
-		return;
-
-	next = rb_next(&my_rsv->rsv_node);
-
-	if (!next)
-		my_rsv->rsv_end += size;
-	else {
-		next_rsv = rb_entry(next, struct ext4_reserve_window_node, rsv_node);
-
-		if ((next_rsv->rsv_start - my_rsv->rsv_end - 1) >= size)
-			my_rsv->rsv_end += size;
-		else
-			my_rsv->rsv_end = next_rsv->rsv_start - 1;
-	}
-	spin_unlock(rsv_lock);
-}
-
-/**
- * ext4_try_to_allocate_with_rsv()
- * @sb:			superblock
- * @handle:		handle to this transaction
- * @group:		given allocation block group
- * @bitmap_bh:		bufferhead holds the block bitmap
- * @grp_goal:		given target block within the group
- * @count:		target number of blocks to allocate
- * @my_rsv:		reservation window
- * @errp:		pointer to store the error code
- *
- * This is the main function used to allocate a new block and its reservation
- * window.
- *
- * Each time when a new block allocation is need, first try to allocate from
- * its own reservation.  If it does not have a reservation window, instead of
- * looking for a free bit on bitmap first, then look up the reservation list to
- * see if it is inside somebody else's reservation window, we try to allocate a
- * reservation window for it starting from the goal first. Then do the block
- * allocation within the reservation window.
- *
- * This will avoid keeping on searching the reservation list again and
- * again when somebody is looking for a free block (without
- * reservation), and there are lots of free blocks, but they are all
- * being reserved.
- *
- * We use a red-black tree for the per-filesystem reservation list.
- *
- */
-static ext4_grpblk_t
-ext4_try_to_allocate_with_rsv(struct super_block *sb, handle_t *handle,
-			ext4_group_t group, struct buffer_head *bitmap_bh,
-			ext4_grpblk_t grp_goal,
-			struct ext4_reserve_window_node *my_rsv,
-			unsigned long *count, int *errp)
-{
-	ext4_fsblk_t group_first_block, group_last_block;
-	ext4_grpblk_t ret = 0;
-	int fatal;
-	unsigned long num = *count;
-
-	*errp = 0;
-
-	/*
-	 * Make sure we use undo access for the bitmap, because it is critical
-	 * that we do the frozen_data COW on bitmap buffers in all cases even
-	 * if the buffer is in BJ_Forget state in the committing transaction.
-	 */
-	BUFFER_TRACE(bitmap_bh, "get undo access for new block");
-	fatal = ext4_journal_get_undo_access(handle, bitmap_bh);
-	if (fatal) {
-		*errp = fatal;
-		return -1;
-	}
-
-	/*
-	 * we don't deal with reservation when
-	 * filesystem is mounted without reservation
-	 * or the file is not a regular file
-	 * or last attempt to allocate a block with reservation turned on failed
-	 */
-	if (my_rsv == NULL) {
-		ret = ext4_try_to_allocate(sb, handle, group, bitmap_bh,
-						grp_goal, count, NULL);
-		goto out;
-	}
-	/*
-	 * grp_goal is a group relative block number (if there is a goal)
-	 * 0 <= grp_goal < EXT4_BLOCKS_PER_GROUP(sb)
-	 * first block is a filesystem wide block number
-	 * first block is the block number of the first block in this group
-	 */
-	group_first_block = ext4_group_first_block_no(sb, group);
-	group_last_block = group_first_block + (EXT4_BLOCKS_PER_GROUP(sb) - 1);
-
-	/*
-	 * Basically we will allocate a new block from inode's reservation
-	 * window.
-	 *
-	 * We need to allocate a new reservation window, if:
-	 * a) inode does not have a reservation window; or
-	 * b) last attempt to allocate a block from existing reservation
-	 *    failed; or
-	 * c) we come here with a goal and with a reservation window
-	 *
-	 * We do not need to allocate a new reservation window if we come here
-	 * at the beginning with a goal and the goal is inside the window, or
-	 * we don't have a goal but already have a reservation window.
-	 * then we could go to allocate from the reservation window directly.
-	 */
-	while (1) {
-		if (rsv_is_empty(&my_rsv->rsv_window) || (ret < 0) ||
-			!goal_in_my_reservation(&my_rsv->rsv_window,
-						grp_goal, group, sb)) {
-			if (my_rsv->rsv_goal_size < *count)
-				my_rsv->rsv_goal_size = *count;
-			ret = alloc_new_reservation(my_rsv, grp_goal, sb,
-							group, bitmap_bh);
-			if (ret < 0)
-				break;			/* failed */
-
-			if (!goal_in_my_reservation(&my_rsv->rsv_window,
-							grp_goal, group, sb))
-				grp_goal = -1;
-		} else if (grp_goal >= 0) {
-			int curr = my_rsv->rsv_end -
-					(grp_goal + group_first_block) + 1;
-
-			if (curr < *count)
-				try_to_extend_reservation(my_rsv, sb,
-							*count - curr);
-		}
-
-		if ((my_rsv->rsv_start > group_last_block) ||
-				(my_rsv->rsv_end < group_first_block)) {
-			rsv_window_dump(&EXT4_SB(sb)->s_rsv_window_root, 1);
-			BUG();
-		}
-		ret = ext4_try_to_allocate(sb, handle, group, bitmap_bh,
-					   grp_goal, &num, &my_rsv->rsv_window);
-		if (ret >= 0) {
-			my_rsv->rsv_alloc_hit += num;
-			*count = num;
-			break;				/* succeed */
-		}
-		num = *count;
-	}
-out:
-	if (ret >= 0) {
-		BUFFER_TRACE(bitmap_bh, "journal_dirty_metadata for "
-					"bitmap block");
-		fatal = ext4_journal_dirty_metadata(handle, bitmap_bh);
-		if (fatal) {
-			*errp = fatal;
-			return -1;
-		}
-		return ret;
-	}
-
-	BUFFER_TRACE(bitmap_bh, "journal_release_buffer");
-	ext4_journal_release_buffer(handle, bitmap_bh);
-	return ret;
-}
-
 int ext4_claim_free_blocks(struct ext4_sb_info *sbi,
 						s64 nblocks)
 {
@@ -1702,313 +679,6 @@ int ext4_should_retry_alloc(struct super_block *sb, int *retries)
 	return jbd2_journal_force_commit_nested(EXT4_SB(sb)->s_journal);
 }
 
-/**
- * ext4_old_new_blocks() -- core block bitmap based block allocation function
- *
- * @handle:		handle to this transaction
- * @inode:		file inode
- * @goal:		given target block(filesystem wide)
- * @count:		target number of blocks to allocate
- * @errp:		error code
- *
- * ext4_old_new_blocks uses a goal block to assist allocation and look up
- * the block bitmap directly to do block allocation.  It tries to
- * allocate block(s) from the block group contains the goal block first. If
- * that fails, it will try to allocate block(s) from other block groups
- * without any specific goal block.
- *
- * This function is called when -o nomballoc mount option is enabled
- *
- */
-ext4_fsblk_t ext4_old_new_blocks(handle_t *handle, struct inode *inode,
-			ext4_fsblk_t goal, unsigned long *count, int *errp)
-{
-	struct buffer_head *bitmap_bh = NULL;
-	struct buffer_head *gdp_bh;
-	ext4_group_t group_no;
-	ext4_group_t goal_group;
-	ext4_grpblk_t grp_target_blk;	/* blockgroup relative goal block */
-	ext4_grpblk_t grp_alloc_blk;	/* blockgroup-relative allocated block*/
-	ext4_fsblk_t ret_block;		/* filesyetem-wide allocated block */
-	ext4_group_t bgi;			/* blockgroup iteration index */
-	int fatal = 0, err;
-	int performed_allocation = 0;
-	ext4_grpblk_t free_blocks;	/* number of free blocks in a group */
-	struct super_block *sb;
-	struct ext4_group_desc *gdp;
-	struct ext4_super_block *es;
-	struct ext4_sb_info *sbi;
-	struct ext4_reserve_window_node *my_rsv = NULL;
-	struct ext4_block_alloc_info *block_i;
-	unsigned short windowsz = 0;
-	ext4_group_t ngroups;
-	unsigned long num = *count;
-
-	sb = inode->i_sb;
-	if (!sb) {
-		*errp = -ENODEV;
-		printk(KERN_ERR "ext4_new_block: nonexistent superblock");
-		return 0;
-	}
-
-	sbi = EXT4_SB(sb);
-	if (!EXT4_I(inode)->i_delalloc_reserved_flag) {
-		/*
-		 * With delalloc we already reserved the blocks
-		 */
-		while (*count && ext4_claim_free_blocks(sbi, *count)) {
-			/* let others to free the space */
-			yield();
-			*count = *count >> 1;
-		}
-		if (!*count) {
-			*errp = -ENOSPC;
-			return 0;	/*return with ENOSPC error */
-		}
-		num = *count;
-	}
-	/*
-	 * Check quota for allocation of this block.
-	 */
-	if (DQUOT_ALLOC_BLOCK(inode, num)) {
-		*errp = -EDQUOT;
-		return 0;
-	}
-
-	sbi = EXT4_SB(sb);
-	es = EXT4_SB(sb)->s_es;
-	ext4_debug("goal=%llu.\n", goal);
-	/*
-	 * Allocate a block from reservation only when
-	 * filesystem is mounted with reservation(default,-o reservation), and
-	 * it's a regular file, and
-	 * the desired window size is greater than 0 (One could use ioctl
-	 * command EXT4_IOC_SETRSVSZ to set the window size to 0 to turn off
-	 * reservation on that particular file)
-	 */
-	block_i = EXT4_I(inode)->i_block_alloc_info;
-	if (block_i && ((windowsz = block_i->rsv_window_node.rsv_goal_size) > 0))
-		my_rsv = &block_i->rsv_window_node;
-
-	/*
-	 * First, test whether the goal block is free.
-	 */
-	if (goal < le32_to_cpu(es->s_first_data_block) ||
-	    goal >= ext4_blocks_count(es))
-		goal = le32_to_cpu(es->s_first_data_block);
-	ext4_get_group_no_and_offset(sb, goal, &group_no, &grp_target_blk);
-	goal_group = group_no;
-retry_alloc:
-	gdp = ext4_get_group_desc(sb, group_no, &gdp_bh);
-	if (!gdp)
-		goto io_error;
-
-	free_blocks = le16_to_cpu(gdp->bg_free_blocks_count);
-
-	if (free_blocks > 0) {
-		/*
-		 * try to allocate with group target block
-		 * in the goal group. If we have low free_blocks
-		 * count turn off reservation
-		 */
-		if (my_rsv && (free_blocks < windowsz)
-			&& (rsv_is_empty(&my_rsv->rsv_window)))
-			my_rsv = NULL;
-
-		bitmap_bh = ext4_read_block_bitmap(sb, group_no);
-		if (!bitmap_bh)
-			goto io_error;
-		grp_alloc_blk = ext4_try_to_allocate_with_rsv(sb, handle,
-					group_no, bitmap_bh, grp_target_blk,
-					my_rsv,	&num, &fatal);
-		if (fatal)
-			goto out;
-		if (grp_alloc_blk >= 0)
-			goto allocated;
-	}
-
-	ngroups = EXT4_SB(sb)->s_groups_count;
-	smp_rmb();
-
-	/*
-	 * Now search the rest of the groups.  We assume that
-	 * group_no and gdp correctly point to the last group visited.
-	 */
-	for (bgi = 0; bgi < ngroups; bgi++) {
-		group_no++;
-		if (group_no >= ngroups)
-			group_no = 0;
-		gdp = ext4_get_group_desc(sb, group_no, &gdp_bh);
-		if (!gdp)
-			goto io_error;
-		free_blocks = le16_to_cpu(gdp->bg_free_blocks_count);
-		/*
-		 * skip this group if the number of
-		 * free blocks is less than half of the reservation
-		 * window size.
-		 */
-		if (my_rsv && (free_blocks <= (windowsz/2)))
-			continue;
-
-		brelse(bitmap_bh);
-		bitmap_bh = ext4_read_block_bitmap(sb, group_no);
-		if (!bitmap_bh)
-			goto io_error;
-		/*
-		 * try to allocate block(s) from this group, without a goal(-1).
-		 */
-		grp_alloc_blk = ext4_try_to_allocate_with_rsv(sb, handle,
-					group_no, bitmap_bh, -1, my_rsv,
-					&num, &fatal);
-		if (fatal)
-			goto out;
-		if (grp_alloc_blk >= 0)
-			goto allocated;
-	}
-	/*
-	 * We may end up a bogus ealier ENOSPC error due to
-	 * filesystem is "full" of reservations, but
-	 * there maybe indeed free blocks avaliable on disk
-	 * In this case, we just forget about the reservations
-	 * just do block allocation as without reservations.
-	 */
-	if (my_rsv) {
-		my_rsv = NULL;
-		windowsz = 0;
-		group_no = goal_group;
-		goto retry_alloc;
-	}
-	/* No space left on the device */
-	*errp = -ENOSPC;
-	goto out;
-
-allocated:
-
-	ext4_debug("using block group %lu(%d)\n",
-			group_no, gdp->bg_free_blocks_count);
-
-	BUFFER_TRACE(gdp_bh, "get_write_access");
-	fatal = ext4_journal_get_write_access(handle, gdp_bh);
-	if (fatal)
-		goto out;
-
-	ret_block = grp_alloc_blk + ext4_group_first_block_no(sb, group_no);
-
-	if (in_range(ext4_block_bitmap(sb, gdp), ret_block, num) ||
-	    in_range(ext4_inode_bitmap(sb, gdp), ret_block, num) ||
-	    in_range(ret_block, ext4_inode_table(sb, gdp),
-		     EXT4_SB(sb)->s_itb_per_group) ||
-	    in_range(ret_block + num - 1, ext4_inode_table(sb, gdp),
-		     EXT4_SB(sb)->s_itb_per_group)) {
-		ext4_error(sb, "ext4_new_block",
-			    "Allocating block in system zone - "
-			    "blocks from %llu, length %lu",
-			     ret_block, num);
-		/*
-		 * claim_block marked the blocks we allocated
-		 * as in use. So we may want to selectively
-		 * mark some of the blocks as free
-		 */
-		goto retry_alloc;
-	}
-
-	performed_allocation = 1;
-
-#ifdef CONFIG_JBD2_DEBUG
-	{
-		struct buffer_head *debug_bh;
-
-		/* Record bitmap buffer state in the newly allocated block */
-		debug_bh = sb_find_get_block(sb, ret_block);
-		if (debug_bh) {
-			BUFFER_TRACE(debug_bh, "state when allocated");
-			BUFFER_TRACE2(debug_bh, bitmap_bh, "bitmap state");
-			brelse(debug_bh);
-		}
-	}
-	jbd_lock_bh_state(bitmap_bh);
-	spin_lock(sb_bgl_lock(sbi, group_no));
-	if (buffer_jbd(bitmap_bh) && bh2jh(bitmap_bh)->b_committed_data) {
-		int i;
-
-		for (i = 0; i < num; i++) {
-			if (ext4_test_bit(grp_alloc_blk+i,
-					bh2jh(bitmap_bh)->b_committed_data)) {
-				printk(KERN_ERR "%s: block was unexpectedly "
-				       "set in b_committed_data\n", __func__);
-			}
-		}
-	}
-	ext4_debug("found bit %d\n", grp_alloc_blk);
-	spin_unlock(sb_bgl_lock(sbi, group_no));
-	jbd_unlock_bh_state(bitmap_bh);
-#endif
-
-	if (ret_block + num - 1 >= ext4_blocks_count(es)) {
-		ext4_error(sb, "ext4_new_block",
-			    "block(%llu) >= blocks count(%llu) - "
-			    "block_group = %lu, es == %p ", ret_block,
-			ext4_blocks_count(es), group_no, es);
-		goto out;
-	}
-
-	/*
-	 * It is up to the caller to add the new buffer to a journal
-	 * list of some description.  We don't know in advance whether
-	 * the caller wants to use it as metadata or data.
-	 */
-	spin_lock(sb_bgl_lock(sbi, group_no));
-	if (gdp->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT))
-		gdp->bg_flags &= cpu_to_le16(~EXT4_BG_BLOCK_UNINIT);
-	le16_add_cpu(&gdp->bg_free_blocks_count, -num);
-	gdp->bg_checksum = ext4_group_desc_csum(sbi, group_no, gdp);
-	spin_unlock(sb_bgl_lock(sbi, group_no));
-	percpu_counter_sub(&sbi->s_freeblocks_counter, num);
-	/*
-	 * Now reduce the dirty block count also. Should not go negative
-	 */
-	if (!EXT4_I(inode)->i_delalloc_reserved_flag)
-		percpu_counter_sub(&sbi->s_dirtyblocks_counter, *count);
-	else
-		percpu_counter_sub(&sbi->s_dirtyblocks_counter, num);
-	if (sbi->s_log_groups_per_flex) {
-		ext4_group_t flex_group = ext4_flex_group(sbi, group_no);
-		spin_lock(sb_bgl_lock(sbi, flex_group));
-		sbi->s_flex_groups[flex_group].free_blocks -= num;
-		spin_unlock(sb_bgl_lock(sbi, flex_group));
-	}
-
-	BUFFER_TRACE(gdp_bh, "journal_dirty_metadata for group descriptor");
-	err = ext4_journal_dirty_metadata(handle, gdp_bh);
-	if (!fatal)
-		fatal = err;
-
-	sb->s_dirt = 1;
-	if (fatal)
-		goto out;
-
-	*errp = 0;
-	brelse(bitmap_bh);
-	DQUOT_FREE_BLOCK(inode, *count-num);
-	*count = num;
-	return ret_block;
-
-io_error:
-	*errp = -EIO;
-out:
-	if (fatal) {
-		*errp = fatal;
-		ext4_std_error(sb, fatal);
-	}
-	/*
-	 * Undo the block allocation
-	 */
-	if (!performed_allocation)
-		DQUOT_FREE_BLOCK(inode, *count);
-	brelse(bitmap_bh);
-	return 0;
-}
-
 #define EXT4_META_BLOCK 0x1
 
 static ext4_fsblk_t do_blk_alloc(handle_t *handle, struct inode *inode,
@@ -2018,10 +688,6 @@ static ext4_fsblk_t do_blk_alloc(handle_t *handle, struct inode *inode,
 	struct ext4_allocation_request ar;
 	ext4_fsblk_t ret;
 
-	if (!test_opt(inode->i_sb, MBALLOC)) {
-		return ext4_old_new_blocks(handle, inode, goal, count, errp);
-	}
-
 	memset(&ar, 0, sizeof(ar));
 	/* Fill with neighbour allocated blocks */
 
@@ -2242,3 +908,4 @@ unsigned long ext4_bg_num_gdb(struct super_block *sb, ext4_group_t group)
 	return ext4_bg_num_gdb_meta(sb,group);
 
 }
+

fs/ext4/ext4.h

@@ -539,7 +539,6 @@ do {									       \
 #define EXT4_MOUNT_JOURNAL_CHECKSUM	0x800000 /* Journal checksums */
 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT	0x1000000 /* Journal Async Commit */
 #define EXT4_MOUNT_I_VERSION            0x2000000 /* i_version support */
-#define EXT4_MOUNT_MBALLOC		0x4000000 /* Buddy allocation support */
 #define EXT4_MOUNT_DELALLOC		0x8000000 /* Delalloc support */
 /* Compatibility, for having both ext2_fs.h and ext4_fs.h included at once */
 #ifndef _LINUX_EXT2_FS_H
@@ -1002,8 +1001,6 @@ extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
 extern ext4_fsblk_t ext4_new_blocks(handle_t *handle, struct inode *inode,
 					ext4_lblk_t iblock, ext4_fsblk_t goal,
 					unsigned long *count, int *errp);
-extern ext4_fsblk_t ext4_old_new_blocks(handle_t *handle, struct inode *inode,
-			ext4_fsblk_t goal, unsigned long *count, int *errp);
 extern int ext4_claim_free_blocks(struct ext4_sb_info *sbi, s64 nblocks);
 extern ext4_fsblk_t ext4_has_free_blocks(struct ext4_sb_info *sbi,
 					 s64 nblocks);
@@ -1018,8 +1015,6 @@ extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
 						    ext4_group_t block_group,
 						    struct buffer_head ** bh);
 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
-extern void ext4_init_block_alloc_info(struct inode *);
-extern void ext4_rsv_window_add(struct super_block *sb, struct ext4_reserve_window_node *rsv);
 
 /* dir.c */
 extern int ext4_check_dir_entry(const char *, struct inode *,
@@ -1054,7 +1049,7 @@ extern int ext4_mb_release(struct super_block *);
 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
 				struct ext4_allocation_request *, int *);
 extern int ext4_mb_reserve_blocks(struct super_block *, int);
-extern void ext4_mb_discard_inode_preallocations(struct inode *);
+extern void ext4_discard_preallocations(struct inode *);
 extern int __init init_ext4_mballoc(void);
 extern void exit_ext4_mballoc(void);
 extern void ext4_mb_free_blocks(handle_t *, struct inode *,
@@ -1084,7 +1079,6 @@ extern int  ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
 				struct kstat *stat);
 extern void ext4_delete_inode(struct inode *);
 extern int  ext4_sync_inode(handle_t *, struct inode *);
-extern void ext4_discard_reservation(struct inode *);
 extern void ext4_dirty_inode(struct inode *);
 extern int ext4_change_inode_journal_flag(struct inode *, int);
 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);

fs/ext4/ext4_i.h

@@ -33,38 +33,6 @@ typedef __u32 ext4_lblk_t;
 /* data type for block group number */
 typedef unsigned long ext4_group_t;
 
-struct ext4_reserve_window {
-	ext4_fsblk_t	_rsv_start;	/* First byte reserved */
-	ext4_fsblk_t	_rsv_end;	/* Last byte reserved or 0 */
-};
-
-struct ext4_reserve_window_node {
-	struct rb_node		rsv_node;
-	__u32			rsv_goal_size;
-	__u32			rsv_alloc_hit;
-	struct ext4_reserve_window	rsv_window;
-};
-
-struct ext4_block_alloc_info {
-	/* information about reservation window */
-	struct ext4_reserve_window_node rsv_window_node;
-	/*
-	 * was i_next_alloc_block in ext4_inode_info
-	 * is the logical (file-relative) number of the
-	 * most-recently-allocated block in this file.
-	 * We use this for detecting linearly ascending allocation requests.
-	 */
-	ext4_lblk_t last_alloc_logical_block;
-	/*
-	 * Was i_next_alloc_goal in ext4_inode_info
-	 * is the *physical* companion to i_next_alloc_block.
-	 * it the physical block number of the block which was most-recentl
-	 * allocated to this file.  This give us the goal (target) for the next
-	 * allocation when we detect linearly ascending requests.
-	 */
-	ext4_fsblk_t last_alloc_physical_block;
-};
-
 #define rsv_start rsv_window._rsv_start
 #define rsv_end rsv_window._rsv_end
 
@@ -97,9 +65,6 @@ struct ext4_inode_info {
 	ext4_group_t	i_block_group;
 	__u32	i_state;		/* Dynamic state flags for ext4 */
 
-	/* block reservation info */
-	struct ext4_block_alloc_info *i_block_alloc_info;
-
 	ext4_lblk_t		i_dir_start_lookup;
 #ifdef CONFIG_EXT4DEV_FS_XATTR
 	/*

fs/ext4/ext4_sb.h

@@ -67,7 +67,6 @@ struct ext4_sb_info {
 	/* root of the per fs reservation window tree */
 	spinlock_t s_rsv_window_lock;
 	struct rb_root s_rsv_window_root;
-	struct ext4_reserve_window_node s_rsv_window_head;
 
 	/* Journaling */
 	struct inode *s_journal_inode;

fs/ext4/extents.c

@@ -2697,11 +2697,8 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
 		goto out2;
 	}
 	/*
-	 * Okay, we need to do block allocation.  Lazily initialize the block
-	 * allocation info here if necessary.
+	 * Okay, we need to do block allocation.
 	 */
-	if (S_ISREG(inode->i_mode) && (!EXT4_I(inode)->i_block_alloc_info))
-		ext4_init_block_alloc_info(inode);
 
 	/* find neighbour allocated blocks */
 	ar.lleft = iblock;
@@ -2761,7 +2758,7 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
 		/* free data blocks we just allocated */
 		/* not a good idea to call discard here directly,
 		 * but otherwise we'd need to call it every free() */
-		ext4_mb_discard_inode_preallocations(inode);
+		ext4_discard_preallocations(inode);
 		ext4_free_blocks(handle, inode, ext_pblock(&newex),
 					ext4_ext_get_actual_len(&newex), 0);
 		goto out2;
@@ -2825,7 +2822,7 @@ void ext4_ext_truncate(struct inode *inode)
 	down_write(&EXT4_I(inode)->i_data_sem);
 	ext4_ext_invalidate_cache(inode);
 
-	ext4_discard_reservation(inode);
+	ext4_discard_preallocations(inode);
 
 	/*
 	 * TODO: optimization is possible here.

fs/ext4/file.c

@@ -38,7 +38,7 @@ static int ext4_release_file(struct inode *inode, struct file *filp)
 			(atomic_read(&inode->i_writecount) == 1))
 	{
 		down_write(&EXT4_I(inode)->i_data_sem);
-		ext4_discard_reservation(inode);
+		ext4_discard_preallocations(inode);
 		up_write(&EXT4_I(inode)->i_data_sem);
 	}
 	if (is_dx(inode) && filp->private_data)

fs/ext4/ialloc.c

@@ -817,7 +817,6 @@ got:
 		ei->i_flags &= ~EXT4_DIRSYNC_FL;
 	ei->i_file_acl = 0;
 	ei->i_dtime = 0;
-	ei->i_block_alloc_info = NULL;
 	ei->i_block_group = group;
 
 	ext4_set_inode_flags(inode);

fs/ext4/inode.c

@@ -486,18 +486,9 @@ static ext4_fsblk_t ext4_find_near(struct inode *inode, Indirect *ind)
 static ext4_fsblk_t ext4_find_goal(struct inode *inode, ext4_lblk_t block,
 		Indirect *partial)
 {
-	struct ext4_block_alloc_info *block_i;
-
-	block_i =  EXT4_I(inode)->i_block_alloc_info;
-
 	/*
-	 * try the heuristic for sequential allocation,
-	 * failing that at least try to get decent locality.
+	 * XXX need to get goal block from mballoc's data structures
 	 */
-	if (block_i && (block == block_i->last_alloc_logical_block + 1)
-		&& (block_i->last_alloc_physical_block != 0)) {
-		return block_i->last_alloc_physical_block + 1;
-	}
 
 	return ext4_find_near(inode, partial);
 }
@@ -757,10 +748,8 @@ static int ext4_splice_branch(handle_t *handle, struct inode *inode,
 {
 	int i;
 	int err = 0;
-	struct ext4_block_alloc_info *block_i;
 	ext4_fsblk_t current_block;
 
-	block_i = EXT4_I(inode)->i_block_alloc_info;
 	/*
 	 * If we're splicing into a [td]indirect block (as opposed to the
 	 * inode) then we need to get write access to the [td]indirect block
@@ -786,17 +775,6 @@ static int ext4_splice_branch(handle_t *handle, struct inode *inode,
 			*(where->p + i) = cpu_to_le32(current_block++);
 	}
 
-	/*
-	 * update the most recently allocated logical & physical block
-	 * in i_block_alloc_info, to assist find the proper goal block for next
-	 * allocation
-	 */
-	if (block_i) {
-		block_i->last_alloc_logical_block = block + blks - 1;
-		block_i->last_alloc_physical_block =
-				le32_to_cpu(where[num].key) + blks - 1;
-	}
-
 	/* We are done with atomic stuff, now do the rest of housekeeping */
 
 	inode->i_ctime = ext4_current_time(inode);
@@ -914,12 +892,8 @@ int ext4_get_blocks_handle(handle_t *handle, struct inode *inode,
 		goto cleanup;
 
 	/*
-	 * Okay, we need to do block allocation.  Lazily initialize the block
-	 * allocation info here if necessary
+	 * Okay, we need to do block allocation.
 	*/
-	if (S_ISREG(inode->i_mode) && (!ei->i_block_alloc_info))
-		ext4_init_block_alloc_info(inode);
-
 	goal = ext4_find_goal(inode, iblock, partial);
 
 	/* the number of blocks need to allocate for [d,t]indirect blocks */
@@ -3738,7 +3712,7 @@ void ext4_truncate(struct inode *inode)
 	 */
 	down_write(&ei->i_data_sem);
 
-	ext4_discard_reservation(inode);
+	ext4_discard_preallocations(inode);
 
 	/*
 	 * The orphan list entry will now protect us from any crash which
@@ -4071,7 +4045,6 @@ struct inode *ext4_iget(struct super_block *sb, unsigned long ino)
 	ei->i_acl = EXT4_ACL_NOT_CACHED;
 	ei->i_default_acl = EXT4_ACL_NOT_CACHED;
 #endif
-	ei->i_block_alloc_info = NULL;
 
 	ret = __ext4_get_inode_loc(inode, &iloc, 0);
 	if (ret < 0)

fs/ext4/ioctl.c

@@ -23,7 +23,6 @@ long ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 	struct inode *inode = filp->f_dentry->d_inode;
 	struct ext4_inode_info *ei = EXT4_I(inode);
 	unsigned int flags;
-	unsigned short rsv_window_size;
 
 	ext4_debug("cmd = %u, arg = %lu\n", cmd, arg);
 
@@ -190,49 +189,6 @@ setversion_out:
 			return ret;
 		}
 #endif
-	case EXT4_IOC_GETRSVSZ:
-		if (test_opt(inode->i_sb, RESERVATION)
-			&& S_ISREG(inode->i_mode)
-			&& ei->i_block_alloc_info) {
-			rsv_window_size = ei->i_block_alloc_info->rsv_window_node.rsv_goal_size;
-			return put_user(rsv_window_size, (int __user *)arg);
-		}
-		return -ENOTTY;
-	case EXT4_IOC_SETRSVSZ: {
-		int err;
-
-		if (!test_opt(inode->i_sb, RESERVATION) || !S_ISREG(inode->i_mode))
-			return -ENOTTY;
-
-		if (!is_owner_or_cap(inode))
-			return -EACCES;
-
-		if (get_user(rsv_window_size, (int __user *)arg))
-			return -EFAULT;
-
-		err = mnt_want_write(filp->f_path.mnt);
-		if (err)
-			return err;
-
-		if (rsv_window_size > EXT4_MAX_RESERVE_BLOCKS)
-			rsv_window_size = EXT4_MAX_RESERVE_BLOCKS;
-
-		/*
-		 * need to allocate reservation structure for this inode
-		 * before set the window size
-		 */
-		down_write(&ei->i_data_sem);
-		if (!ei->i_block_alloc_info)
-			ext4_init_block_alloc_info(inode);
-
-		if (ei->i_block_alloc_info){
-			struct ext4_reserve_window_node *rsv = &ei->i_block_alloc_info->rsv_window_node;
-			rsv->rsv_goal_size = rsv_window_size;
-		}
-		up_write(&ei->i_data_sem);
-		mnt_drop_write(filp->f_path.mnt);
-		return 0;
-	}
 	case EXT4_IOC_GROUP_EXTEND: {
 		ext4_fsblk_t n_blocks_count;
 		struct super_block *sb = inode->i_sb;

fs/ext4/mballoc.c

@@ -534,9 +534,6 @@ static int __mb_check_buddy(struct ext4_buddy *e4b, char *file,
 	void *buddy;
 	void *buddy2;
 
-	if (!test_opt(sb, MBALLOC))
-		return 0;
-
 	{
 		static int mb_check_counter;
 		if (mb_check_counter++ % 100 != 0)
@@ -2487,19 +2484,14 @@ int ext4_mb_init(struct super_block *sb, int needs_recovery)
 	unsigned max;
 	int ret;
 
-	if (!test_opt(sb, MBALLOC))
-		return 0;
-
 	i = (sb->s_blocksize_bits + 2) * sizeof(unsigned short);
 
 	sbi->s_mb_offsets = kmalloc(i, GFP_KERNEL);
 	if (sbi->s_mb_offsets == NULL) {
-		clear_opt(sbi->s_mount_opt, MBALLOC);
 		return -ENOMEM;
 	}
 	sbi->s_mb_maxs = kmalloc(i, GFP_KERNEL);
 	if (sbi->s_mb_maxs == NULL) {
-		clear_opt(sbi->s_mount_opt, MBALLOC);
 		kfree(sbi->s_mb_maxs);
 		return -ENOMEM;
 	}
@@ -2522,7 +2514,6 @@ int ext4_mb_init(struct super_block *sb, int needs_recovery)
 	/* init file for buddy data */
 	ret = ext4_mb_init_backend(sb);
 	if (ret != 0) {
-		clear_opt(sbi->s_mount_opt, MBALLOC);
 		kfree(sbi->s_mb_offsets);
 		kfree(sbi->s_mb_maxs);
 		return ret;
@@ -2544,7 +2535,6 @@ int ext4_mb_init(struct super_block *sb, int needs_recovery)
 
 	sbi->s_locality_groups = alloc_percpu(struct ext4_locality_group);
 	if (sbi->s_locality_groups == NULL) {
-		clear_opt(sbi->s_mount_opt, MBALLOC);
 		kfree(sbi->s_mb_offsets);
 		kfree(sbi->s_mb_maxs);
 		return -ENOMEM;
@@ -2590,9 +2580,6 @@ int ext4_mb_release(struct super_block *sb)
 	struct ext4_group_info *grinfo;
 	struct ext4_sb_info *sbi = EXT4_SB(sb);
 
-	if (!test_opt(sb, MBALLOC))
-		return 0;
-
 	/* release freed, non-committed blocks */
 	spin_lock(&sbi->s_md_lock);
 	list_splice_init(&sbi->s_closed_transaction,
@@ -3805,7 +3792,7 @@ out:
  *
  * FIXME!! Make sure it is valid at all the call sites
  */
-void ext4_mb_discard_inode_preallocations(struct inode *inode)
+void ext4_discard_preallocations(struct inode *inode)
 {
 	struct ext4_inode_info *ei = EXT4_I(inode);
 	struct super_block *sb = inode->i_sb;
@@ -3817,7 +3804,7 @@ void ext4_mb_discard_inode_preallocations(struct inode *inode)
 	struct ext4_buddy e4b;
 	int err;
 
-	if (!test_opt(sb, MBALLOC) || !S_ISREG(inode->i_mode)) {
+	if (!S_ISREG(inode->i_mode)) {
 		/*BUG_ON(!list_empty(&ei->i_prealloc_list));*/
 		return;
 	}
@@ -4300,11 +4287,6 @@ ext4_fsblk_t ext4_mb_new_blocks(handle_t *handle,
 	sb = ar->inode->i_sb;
 	sbi = EXT4_SB(sb);
 
-	if (!test_opt(sb, MBALLOC)) {
-		block = ext4_old_new_blocks(handle, ar->inode, ar->goal,
-					    &(ar->len), errp);
-		return block;
-	}
 	if (!EXT4_I(ar->inode)->i_delalloc_reserved_flag) {
 		/*
 		 * With delalloc we already reserved the blocks

fs/ext4/resize.c

@@ -870,11 +870,10 @@ int ext4_group_add(struct super_block *sb, struct ext4_new_group_data *input)
 	 * We can allocate memory for mb_alloc based on the new group
 	 * descriptor
 	 */
-	if (test_opt(sb, MBALLOC)) {
-		err = ext4_mb_add_more_groupinfo(sb, input->group, gdp);
-		if (err)
-			goto exit_journal;
-	}
+	err = ext4_mb_add_more_groupinfo(sb, input->group, gdp);
+	if (err)
+		goto exit_journal;
+
 	/*
 	 * Make the new blocks and inodes valid next.  We do this before
 	 * increasing the group count so that once the group is enabled,
@@ -1086,8 +1085,15 @@ int ext4_group_extend(struct super_block *sb, struct ext4_super_block *es,
 	/*
 	 * Mark mballoc pages as not up to date so that they will be updated
 	 * next time they are loaded by ext4_mb_load_buddy.
+	 *
+	 * XXX Bad, Bad, BAD!!!  We should not be overloading the
+	 * Uptodate flag, particularly on thte bitmap bh, as way of
+	 * hinting to ext4_mb_load_buddy() that it needs to be
+	 * overloaded.  A user could take a LVM snapshot, then do an
+	 * on-line fsck, and clear the uptodate flag, and this would
+	 * not be a bug in userspace, but a bug in the kernel.  FIXME!!!
 	 */
-	if (test_opt(sb, MBALLOC)) {
+	{
 		struct ext4_sb_info *sbi = EXT4_SB(sb);
 		struct inode *inode = sbi->s_buddy_cache;
 		int blocks_per_page;

fs/ext4/super.c

@@ -574,7 +574,6 @@ static struct inode *ext4_alloc_inode(struct super_block *sb)
 	ei->i_acl = EXT4_ACL_NOT_CACHED;
 	ei->i_default_acl = EXT4_ACL_NOT_CACHED;
 #endif
-	ei->i_block_alloc_info = NULL;
 	ei->vfs_inode.i_version = 1;
 	ei->vfs_inode.i_data.writeback_index = 0;
 	memset(&ei->i_cached_extent, 0, sizeof(struct ext4_ext_cache));
@@ -633,7 +632,6 @@ static void destroy_inodecache(void)
 
 static void ext4_clear_inode(struct inode *inode)
 {
-	struct ext4_block_alloc_info *rsv = EXT4_I(inode)->i_block_alloc_info;
 #ifdef CONFIG_EXT4DEV_FS_POSIX_ACL
 	if (EXT4_I(inode)->i_acl &&
 			EXT4_I(inode)->i_acl != EXT4_ACL_NOT_CACHED) {
@@ -646,10 +644,7 @@ static void ext4_clear_inode(struct inode *inode)
 		EXT4_I(inode)->i_default_acl = EXT4_ACL_NOT_CACHED;
 	}
 #endif
-	ext4_discard_reservation(inode);
-	EXT4_I(inode)->i_block_alloc_info = NULL;
-	if (unlikely(rsv))
-		kfree(rsv);
+	ext4_discard_preallocations(inode);
 	jbd2_journal_release_jbd_inode(EXT4_SB(inode->i_sb)->s_journal,
 				       &EXT4_I(inode)->jinode);
 }
@@ -760,8 +755,6 @@ static int ext4_show_options(struct seq_file *seq, struct vfsmount *vfs)
 		seq_puts(seq, ",nobh");
 	if (!test_opt(sb, EXTENTS))
 		seq_puts(seq, ",noextents");
-	if (!test_opt(sb, MBALLOC))
-		seq_puts(seq, ",nomballoc");
 	if (test_opt(sb, I_VERSION))
 		seq_puts(seq, ",i_version");
 	if (!test_opt(sb, DELALLOC))
@@ -1373,12 +1366,6 @@ set_qf_format:
 		case Opt_nodelalloc:
 			clear_opt(sbi->s_mount_opt, DELALLOC);
 			break;
-		case Opt_mballoc:
-			set_opt(sbi->s_mount_opt, MBALLOC);
-			break;
-		case Opt_nomballoc:
-			clear_opt(sbi->s_mount_opt, MBALLOC);
-			break;
 		case Opt_stripe:
 			if (match_int(&args[0], &option))
 				return 0;
@@ -2040,11 +2027,6 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
 		ext4_warning(sb, __func__,
 			"extents feature not enabled on this filesystem, "
 			"use tune2fs.\n");
-	/*
-	 * turn on mballoc code by default in ext4 filesystem
-	 * Use -o nomballoc to turn it off
-	 */
-	set_opt(sbi->s_mount_opt, MBALLOC);
 
 	/*
 	 * enable delayed allocation by default
@@ -2301,19 +2283,6 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
 		goto failed_mount3;
 	}
 
-	/* per fileystem reservation list head & lock */
-	spin_lock_init(&sbi->s_rsv_window_lock);
-	sbi->s_rsv_window_root = RB_ROOT;
-	/* Add a single, static dummy reservation to the start of the
-	 * reservation window list --- it gives us a placeholder for
-	 * append-at-start-of-list which makes the allocation logic
-	 * _much_ simpler. */
-	sbi->s_rsv_window_head.rsv_start = EXT4_RESERVE_WINDOW_NOT_ALLOCATED;
-	sbi->s_rsv_window_head.rsv_end = EXT4_RESERVE_WINDOW_NOT_ALLOCATED;
-	sbi->s_rsv_window_head.rsv_alloc_hit = 0;
-	sbi->s_rsv_window_head.rsv_goal_size = 0;
-	ext4_rsv_window_add(sb, &sbi->s_rsv_window_head);
-
 	sbi->s_stripe = ext4_get_stripe_size(sbi);
 
 	/*
@@ -2510,7 +2479,12 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
 		printk(KERN_INFO "EXT4-fs: delayed allocation enabled\n");
 
 	ext4_ext_init(sb);
-	ext4_mb_init(sb, needs_recovery);
+	err = ext4_mb_init(sb, needs_recovery);
+	if (err) {
+		printk(KERN_ERR "EXT4-fs: failed to initalize mballoc (%d)\n",
+		       err);
+		goto failed_mount4;
+	}
 
 	lock_kernel();
 	return 0;