1 files changed, 695 insertions, 115 deletions

diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 7a3832577923..94c8ee81f5e1 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -195,8 +195,7 @@ static ext4_fsblk_t ext4_ext_find_goal(struct inode *inode,
 		if (S_ISREG(inode->i_mode))
 			block_group++;
 	}
-	bg_start = (block_group * EXT4_BLOCKS_PER_GROUP(inode->i_sb)) +
-		le32_to_cpu(EXT4_SB(inode->i_sb)->s_es->s_first_data_block);
+	bg_start = ext4_group_first_block_no(inode->i_sb, block_group);
 	last_block = ext4_blocks_count(EXT4_SB(inode->i_sb)->s_es) - 1;
 
 	/*
@@ -296,29 +295,44 @@ static inline int ext4_ext_space_root_idx(struct inode *inode, int check)
  * to allocate @blocks
  * Worse case is one block per extent
  */
-int ext4_ext_calc_metadata_amount(struct inode *inode, int blocks)
+int ext4_ext_calc_metadata_amount(struct inode *inode, sector_t lblock)
 {
-	int lcap, icap, rcap, leafs, idxs, num;
-	int newextents = blocks;
-
-	rcap = ext4_ext_space_root_idx(inode, 0);
-	lcap = ext4_ext_space_block(inode, 0);
-	icap = ext4_ext_space_block_idx(inode, 0);
+	struct ext4_inode_info *ei = EXT4_I(inode);
+	int idxs, num = 0;
 
-	/* number of new leaf blocks needed */
-	num = leafs = (newextents + lcap - 1) / lcap;
+	idxs = ((inode->i_sb->s_blocksize - sizeof(struct ext4_extent_header))
+		/ sizeof(struct ext4_extent_idx));
 
 	/*
-	 * Worse case, we need separate index block(s)
-	 * to link all new leaf blocks
+	 * If the new delayed allocation block is contiguous with the
+	 * previous da block, it can share index blocks with the
+	 * previous block, so we only need to allocate a new index
+	 * block every idxs leaf blocks.  At ldxs**2 blocks, we need
+	 * an additional index block, and at ldxs**3 blocks, yet
+	 * another index blocks.
 	 */
-	idxs = (leafs + icap - 1) / icap;
-	do {
-		num += idxs;
-		idxs = (idxs + icap - 1) / icap;
-	} while (idxs > rcap);
+	if (ei->i_da_metadata_calc_len &&
+	    ei->i_da_metadata_calc_last_lblock+1 == lblock) {
+		if ((ei->i_da_metadata_calc_len % idxs) == 0)
+			num++;
+		if ((ei->i_da_metadata_calc_len % (idxs*idxs)) == 0)
+			num++;
+		if ((ei->i_da_metadata_calc_len % (idxs*idxs*idxs)) == 0) {
+			num++;
+			ei->i_da_metadata_calc_len = 0;
+		} else
+			ei->i_da_metadata_calc_len++;
+		ei->i_da_metadata_calc_last_lblock++;
+		return num;
+	}
 
-	return num;
+	/*
+	 * In the worst case we need a new set of index blocks at
+	 * every level of the inode's extent tree.
+	 */
+	ei->i_da_metadata_calc_len = 1;
+	ei->i_da_metadata_calc_last_lblock = lblock;
+	return ext_depth(inode) + 1;
 }
 
 static int
@@ -425,7 +439,7 @@ static int __ext4_ext_check(const char *function, struct inode *inode,
 	return 0;
 
 corrupted:
-	ext4_error(inode->i_sb, function,
+	__ext4_error(inode->i_sb, function,
 			"bad header/extent in inode #%lu: %s - magic %x, "
 			"entries %u, max %u(%u), depth %u(%u)",
 			inode->i_ino, error_msg, le16_to_cpu(eh->eh_magic),
@@ -688,7 +702,12 @@ ext4_ext_find_extent(struct inode *inode, ext4_lblk_t block,
 		}
 		eh = ext_block_hdr(bh);
 		ppos++;
-		BUG_ON(ppos > depth);
+		if (unlikely(ppos > depth)) {
+			put_bh(bh);
+			EXT4_ERROR_INODE(inode,
+					 "ppos %d > depth %d", ppos, depth);
+			goto err;
+		}
 		path[ppos].p_bh = bh;
 		path[ppos].p_hdr = eh;
 		i--;
@@ -723,7 +742,7 @@ err:
  * insert new index [@logical;@ptr] into the block at @curp;
  * check where to insert: before @curp or after @curp
  */
-static int ext4_ext_insert_index(handle_t *handle, struct inode *inode,
+int ext4_ext_insert_index(handle_t *handle, struct inode *inode,
 				struct ext4_ext_path *curp,
 				int logical, ext4_fsblk_t ptr)
 {
@@ -734,7 +753,12 @@ static int ext4_ext_insert_index(handle_t *handle, struct inode *inode,
 	if (err)
 		return err;
 
-	BUG_ON(logical == le32_to_cpu(curp->p_idx->ei_block));
+	if (unlikely(logical == le32_to_cpu(curp->p_idx->ei_block))) {
+		EXT4_ERROR_INODE(inode,
+				 "logical %d == ei_block %d!",
+				 logical, le32_to_cpu(curp->p_idx->ei_block));
+		return -EIO;
+	}
 	len = EXT_MAX_INDEX(curp->p_hdr) - curp->p_idx;
 	if (logical > le32_to_cpu(curp->p_idx->ei_block)) {
 		/* insert after */
@@ -764,9 +788,17 @@ static int ext4_ext_insert_index(handle_t *handle, struct inode *inode,
 	ext4_idx_store_pblock(ix, ptr);
 	le16_add_cpu(&curp->p_hdr->eh_entries, 1);
 
-	BUG_ON(le16_to_cpu(curp->p_hdr->eh_entries)
-			     > le16_to_cpu(curp->p_hdr->eh_max));
-	BUG_ON(ix > EXT_LAST_INDEX(curp->p_hdr));
+	if (unlikely(le16_to_cpu(curp->p_hdr->eh_entries)
+			     > le16_to_cpu(curp->p_hdr->eh_max))) {
+		EXT4_ERROR_INODE(inode,
+				 "logical %d == ei_block %d!",
+				 logical, le32_to_cpu(curp->p_idx->ei_block));
+		return -EIO;
+	}
+	if (unlikely(ix > EXT_LAST_INDEX(curp->p_hdr))) {
+		EXT4_ERROR_INODE(inode, "ix > EXT_LAST_INDEX!");
+		return -EIO;
+	}
 
 	err = ext4_ext_dirty(handle, inode, curp);
 	ext4_std_error(inode->i_sb, err);
@@ -804,7 +836,10 @@ static int ext4_ext_split(handle_t *handle, struct inode *inode,
 
 	/* if current leaf will be split, then we should use
 	 * border from split point */
-	BUG_ON(path[depth].p_ext > EXT_MAX_EXTENT(path[depth].p_hdr));
+	if (unlikely(path[depth].p_ext > EXT_MAX_EXTENT(path[depth].p_hdr))) {
+		EXT4_ERROR_INODE(inode, "p_ext > EXT_MAX_EXTENT!");
+		return -EIO;
+	}
 	if (path[depth].p_ext != EXT_MAX_EXTENT(path[depth].p_hdr)) {
 		border = path[depth].p_ext[1].ee_block;
 		ext_debug("leaf will be split."
@@ -845,7 +880,11 @@ static int ext4_ext_split(handle_t *handle, struct inode *inode,
 
 	/* initialize new leaf */
 	newblock = ablocks[--a];
-	BUG_ON(newblock == 0);
+	if (unlikely(newblock == 0)) {
+		EXT4_ERROR_INODE(inode, "newblock == 0!");
+		err = -EIO;
+		goto cleanup;
+	}
 	bh = sb_getblk(inode->i_sb, newblock);
 	if (!bh) {
 		err = -EIO;
@@ -865,7 +904,14 @@ static int ext4_ext_split(handle_t *handle, struct inode *inode,
 	ex = EXT_FIRST_EXTENT(neh);
 
 	/* move remainder of path[depth] to the new leaf */
-	BUG_ON(path[depth].p_hdr->eh_entries != path[depth].p_hdr->eh_max);
+	if (unlikely(path[depth].p_hdr->eh_entries !=
+		     path[depth].p_hdr->eh_max)) {
+		EXT4_ERROR_INODE(inode, "eh_entries %d != eh_max %d!",
+				 path[depth].p_hdr->eh_entries,
+				 path[depth].p_hdr->eh_max);
+		err = -EIO;
+		goto cleanup;
+	}
 	/* start copy from next extent */
 	/* TODO: we could do it by single memmove */
 	m = 0;
@@ -912,7 +958,11 @@ static int ext4_ext_split(handle_t *handle, struct inode *inode,
 
 	/* create intermediate indexes */
 	k = depth - at - 1;
-	BUG_ON(k < 0);
+	if (unlikely(k < 0)) {
+		EXT4_ERROR_INODE(inode, "k %d < 0!", k);
+		err = -EIO;
+		goto cleanup;
+	}
 	if (k)
 		ext_debug("create %d intermediate indices\n", k);
 	/* insert new index into current index block */
@@ -949,8 +999,14 @@ static int ext4_ext_split(handle_t *handle, struct inode *inode,
 
 		ext_debug("cur 0x%p, last 0x%p\n", path[i].p_idx,
 				EXT_MAX_INDEX(path[i].p_hdr));
-		BUG_ON(EXT_MAX_INDEX(path[i].p_hdr) !=
-				EXT_LAST_INDEX(path[i].p_hdr));
+		if (unlikely(EXT_MAX_INDEX(path[i].p_hdr) !=
+					EXT_LAST_INDEX(path[i].p_hdr))) {
+			EXT4_ERROR_INODE(inode,
+					 "EXT_MAX_INDEX != EXT_LAST_INDEX ee_block %d!",
+					 le32_to_cpu(path[i].p_ext->ee_block));
+			err = -EIO;
+			goto cleanup;
+		}
 		while (path[i].p_idx <= EXT_MAX_INDEX(path[i].p_hdr)) {
 			ext_debug("%d: move %d:%llu in new index %llu\n", i,
 					le32_to_cpu(path[i].p_idx->ei_block),
@@ -1007,7 +1063,8 @@ cleanup:
 		for (i = 0; i < depth; i++) {
 			if (!ablocks[i])
 				continue;
-			ext4_free_blocks(handle, inode, ablocks[i], 1, 1);
+			ext4_free_blocks(handle, inode, 0, ablocks[i], 1,
+					 EXT4_FREE_BLOCKS_METADATA);
 		}
 	}
 	kfree(ablocks);
@@ -1187,7 +1244,10 @@ ext4_ext_search_left(struct inode *inode, struct ext4_ext_path *path,
 	struct ext4_extent *ex;
 	int depth, ee_len;
 
-	BUG_ON(path == NULL);
+	if (unlikely(path == NULL)) {
+		EXT4_ERROR_INODE(inode, "path == NULL *logical %d!", *logical);
+		return -EIO;
+	}
 	depth = path->p_depth;
 	*phys = 0;
 
@@ -1201,15 +1261,33 @@ ext4_ext_search_left(struct inode *inode, struct ext4_ext_path *path,
 	ex = path[depth].p_ext;
 	ee_len = ext4_ext_get_actual_len(ex);
 	if (*logical < le32_to_cpu(ex->ee_block)) {
-		BUG_ON(EXT_FIRST_EXTENT(path[depth].p_hdr) != ex);
+		if (unlikely(EXT_FIRST_EXTENT(path[depth].p_hdr) != ex)) {
+			EXT4_ERROR_INODE(inode,
+					 "EXT_FIRST_EXTENT != ex *logical %d ee_block %d!",
+					 *logical, le32_to_cpu(ex->ee_block));
+			return -EIO;
+		}
 		while (--depth >= 0) {
 			ix = path[depth].p_idx;
-			BUG_ON(ix != EXT_FIRST_INDEX(path[depth].p_hdr));
+			if (unlikely(ix != EXT_FIRST_INDEX(path[depth].p_hdr))) {
+				EXT4_ERROR_INODE(inode,
+				  "ix (%d) != EXT_FIRST_INDEX (%d) (depth %d)!",
+				  ix != NULL ? ix->ei_block : 0,
+				  EXT_FIRST_INDEX(path[depth].p_hdr) != NULL ?
+				    EXT_FIRST_INDEX(path[depth].p_hdr)->ei_block : 0,
+				  depth);
+				return -EIO;
+			}
 		}
 		return 0;
 	}
 
-	BUG_ON(*logical < (le32_to_cpu(ex->ee_block) + ee_len));
+	if (unlikely(*logical < (le32_to_cpu(ex->ee_block) + ee_len))) {
+		EXT4_ERROR_INODE(inode,
+				 "logical %d < ee_block %d + ee_len %d!",
+				 *logical, le32_to_cpu(ex->ee_block), ee_len);
+		return -EIO;
+	}
 
 	*logical = le32_to_cpu(ex->ee_block) + ee_len - 1;
 	*phys = ext_pblock(ex) + ee_len - 1;
@@ -1235,7 +1313,10 @@ ext4_ext_search_right(struct inode *inode, struct ext4_ext_path *path,
 	int depth;	/* Note, NOT eh_depth; depth from top of tree */
 	int ee_len;
 
-	BUG_ON(path == NULL);
+	if (unlikely(path == NULL)) {
+		EXT4_ERROR_INODE(inode, "path == NULL *logical %d!", *logical);
+		return -EIO;
+	}
 	depth = path->p_depth;
 	*phys = 0;
 
@@ -1249,17 +1330,32 @@ ext4_ext_search_right(struct inode *inode, struct ext4_ext_path *path,
 	ex = path[depth].p_ext;
 	ee_len = ext4_ext_get_actual_len(ex);
 	if (*logical < le32_to_cpu(ex->ee_block)) {
-		BUG_ON(EXT_FIRST_EXTENT(path[depth].p_hdr) != ex);
+		if (unlikely(EXT_FIRST_EXTENT(path[depth].p_hdr) != ex)) {
+			EXT4_ERROR_INODE(inode,
+					 "first_extent(path[%d].p_hdr) != ex",
+					 depth);
+			return -EIO;
+		}
 		while (--depth >= 0) {
 			ix = path[depth].p_idx;
-			BUG_ON(ix != EXT_FIRST_INDEX(path[depth].p_hdr));
+			if (unlikely(ix != EXT_FIRST_INDEX(path[depth].p_hdr))) {
+				EXT4_ERROR_INODE(inode,
+						 "ix != EXT_FIRST_INDEX *logical %d!",
+						 *logical);
+				return -EIO;
+			}
 		}
 		*logical = le32_to_cpu(ex->ee_block);
 		*phys = ext_pblock(ex);
 		return 0;
 	}
 
-	BUG_ON(*logical < (le32_to_cpu(ex->ee_block) + ee_len));
+	if (unlikely(*logical < (le32_to_cpu(ex->ee_block) + ee_len))) {
+		EXT4_ERROR_INODE(inode,
+				 "logical %d < ee_block %d + ee_len %d!",
+				 *logical, le32_to_cpu(ex->ee_block), ee_len);
+		return -EIO;
+	}
 
 	if (ex != EXT_LAST_EXTENT(path[depth].p_hdr)) {
 		/* next allocated block in this leaf */
@@ -1398,8 +1494,12 @@ static int ext4_ext_correct_indexes(handle_t *handle, struct inode *inode,
 
 	eh = path[depth].p_hdr;
 	ex = path[depth].p_ext;
-	BUG_ON(ex == NULL);
-	BUG_ON(eh == NULL);
+
+	if (unlikely(ex == NULL || eh == NULL)) {
+		EXT4_ERROR_INODE(inode,
+				 "ex %p == NULL or eh %p == NULL", ex, eh);
+		return -EIO;
+	}
 
 	if (depth == 0) {
 		/* there is no tree at all */
@@ -1522,8 +1622,9 @@ int ext4_ext_try_to_merge(struct inode *inode,
 		merge_done = 1;
 		WARN_ON(eh->eh_entries == 0);
 		if (!eh->eh_entries)
-			ext4_error(inode->i_sb, "ext4_ext_try_to_merge",
-			   "inode#%lu, eh->eh_entries = 0!", inode->i_ino);
+			ext4_error(inode->i_sb,
+				   "inode#%lu, eh->eh_entries = 0!",
+				   inode->i_ino);
 	}
 
 	return merge_done;
@@ -1586,7 +1687,7 @@ out:
  */
 int ext4_ext_insert_extent(handle_t *handle, struct inode *inode,
 				struct ext4_ext_path *path,
-				struct ext4_extent *newext)
+				struct ext4_extent *newext, int flag)
 {
 	struct ext4_extent_header *eh;
 	struct ext4_extent *ex, *fex;
@@ -1596,13 +1697,20 @@ int ext4_ext_insert_extent(handle_t *handle, struct inode *inode,
 	ext4_lblk_t next;
 	unsigned uninitialized = 0;
 
-	BUG_ON(ext4_ext_get_actual_len(newext) == 0);
+	if (unlikely(ext4_ext_get_actual_len(newext) == 0)) {
+		EXT4_ERROR_INODE(inode, "ext4_ext_get_actual_len(newext) == 0");
+		return -EIO;
+	}
 	depth = ext_depth(inode);
 	ex = path[depth].p_ext;
-	BUG_ON(path[depth].p_hdr == NULL);
+	if (unlikely(path[depth].p_hdr == NULL)) {
+		EXT4_ERROR_INODE(inode, "path[%d].p_hdr == NULL", depth);
+		return -EIO;
+	}
 
 	/* try to insert block into found extent and return */
-	if (ex && ext4_can_extents_be_merged(inode, ex, newext)) {
+	if (ex && !(flag & EXT4_GET_BLOCKS_PRE_IO)
+		&& ext4_can_extents_be_merged(inode, ex, newext)) {
 		ext_debug("append [%d]%d block to %d:[%d]%d (from %llu)\n",
 				ext4_ext_is_uninitialized(newext),
 				ext4_ext_get_actual_len(newext),
@@ -1722,7 +1830,8 @@ has_space:
 
 merge:
 	/* try to merge extents to the right */
-	ext4_ext_try_to_merge(inode, path, nearex);
+	if (!(flag & EXT4_GET_BLOCKS_PRE_IO))
+		ext4_ext_try_to_merge(inode, path, nearex);
 
 	/* try to merge extents to the left */
 
@@ -1759,7 +1868,9 @@ int ext4_ext_walk_space(struct inode *inode, ext4_lblk_t block,
 	while (block < last && block != EXT_MAX_BLOCK) {
 		num = last - block;
 		/* find extent for this block */
+		down_read(&EXT4_I(inode)->i_data_sem);
 		path = ext4_ext_find_extent(inode, block, path);
+		up_read(&EXT4_I(inode)->i_data_sem);
 		if (IS_ERR(path)) {
 			err = PTR_ERR(path);
 			path = NULL;
@@ -1767,7 +1878,11 @@ int ext4_ext_walk_space(struct inode *inode, ext4_lblk_t block,
 		}
 
 		depth = ext_depth(inode);
-		BUG_ON(path[depth].p_hdr == NULL);
+		if (unlikely(path[depth].p_hdr == NULL)) {
+			EXT4_ERROR_INODE(inode, "path[%d].p_hdr == NULL", depth);
+			err = -EIO;
+			break;
+		}
 		ex = path[depth].p_ext;
 		next = ext4_ext_next_allocated_block(path);
 
@@ -1818,7 +1933,11 @@ int ext4_ext_walk_space(struct inode *inode, ext4_lblk_t block,
 			cbex.ec_type = EXT4_EXT_CACHE_EXTENT;
 		}
 
-		BUG_ON(cbex.ec_len == 0);
+		if (unlikely(cbex.ec_len == 0)) {
+			EXT4_ERROR_INODE(inode, "cbex.ec_len == 0");
+			err = -EIO;
+			break;
+		}
 		err = func(inode, path, &cbex, ex, cbdata);
 		ext4_ext_drop_refs(path);
 
@@ -1932,7 +2051,7 @@ ext4_ext_in_cache(struct inode *inode, ext4_lblk_t block,
 
 	BUG_ON(cex->ec_type != EXT4_EXT_CACHE_GAP &&
 			cex->ec_type != EXT4_EXT_CACHE_EXTENT);
-	if (block >= cex->ec_block && block < cex->ec_block + cex->ec_len) {
+	if (in_range(block, cex->ec_block, cex->ec_len)) {
 		ex->ee_block = cpu_to_le32(cex->ec_block);
 		ext4_ext_store_pblock(ex, cex->ec_start);
 		ex->ee_len = cpu_to_le16(cex->ec_len);
@@ -1955,14 +2074,16 @@ errout:
 static int ext4_ext_rm_idx(handle_t *handle, struct inode *inode,
 			struct ext4_ext_path *path)
 {
-	struct buffer_head *bh;
 	int err;
 	ext4_fsblk_t leaf;
 
 	/* free index block */
 	path--;
 	leaf = idx_pblock(path->p_idx);
-	BUG_ON(path->p_hdr->eh_entries == 0);
+	if (unlikely(path->p_hdr->eh_entries == 0)) {
+		EXT4_ERROR_INODE(inode, "path->p_hdr->eh_entries == 0");
+		return -EIO;
+	}
 	err = ext4_ext_get_access(handle, inode, path);
 	if (err)
 		return err;
@@ -1971,9 +2092,8 @@ static int ext4_ext_rm_idx(handle_t *handle, struct inode *inode,
 	if (err)
 		return err;
 	ext_debug("index is empty, remove it, free block %llu\n", leaf);
-	bh = sb_find_get_block(inode->i_sb, leaf);
-	ext4_forget(handle, 1, inode, bh, leaf);
-	ext4_free_blocks(handle, inode, leaf, 1, 1);
+	ext4_free_blocks(handle, inode, 0, leaf, 1,
+			 EXT4_FREE_BLOCKS_METADATA | EXT4_FREE_BLOCKS_FORGET);
 	return err;
 }
 
@@ -2040,12 +2160,11 @@ static int ext4_remove_blocks(handle_t *handle, struct inode *inode,
 				struct ext4_extent *ex,
 				ext4_lblk_t from, ext4_lblk_t to)
 {
-	struct buffer_head *bh;
 	unsigned short ee_len =  ext4_ext_get_actual_len(ex);
-	int i, metadata = 0;
+	int flags = EXT4_FREE_BLOCKS_FORGET;
 
 	if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode))
-		metadata = 1;
+		flags |= EXT4_FREE_BLOCKS_METADATA;
 #ifdef EXTENTS_STATS
 	{
 		struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
@@ -2070,11 +2189,7 @@ static int ext4_remove_blocks(handle_t *handle, struct inode *inode,
 		num = le32_to_cpu(ex->ee_block) + ee_len - from;
 		start = ext_pblock(ex) + ee_len - num;
 		ext_debug("free last %u blocks starting %llu\n", num, start);
-		for (i = 0; i < num; i++) {
-			bh = sb_find_get_block(inode->i_sb, start + i);
-			ext4_forget(handle, 0, inode, bh, start + i);
-		}
-		ext4_free_blocks(handle, inode, start, num, metadata);
+		ext4_free_blocks(handle, inode, 0, start, num, flags);
 	} else if (from == le32_to_cpu(ex->ee_block)
 		   && to <= le32_to_cpu(ex->ee_block) + ee_len - 1) {
 		printk(KERN_INFO "strange request: removal %u-%u from %u:%u\n",
@@ -2106,8 +2221,10 @@ ext4_ext_rm_leaf(handle_t *handle, struct inode *inode,
 	if (!path[depth].p_hdr)
 		path[depth].p_hdr = ext_block_hdr(path[depth].p_bh);
 	eh = path[depth].p_hdr;
-	BUG_ON(eh == NULL);
-
+	if (unlikely(path[depth].p_hdr == NULL)) {
+		EXT4_ERROR_INODE(inode, "path[%d].p_hdr == NULL", depth);
+		return -EIO;
+	}
 	/* find where to start removing */
 	ex = EXT_LAST_EXTENT(eh);
 
@@ -2165,7 +2282,7 @@ ext4_ext_rm_leaf(handle_t *handle, struct inode *inode,
 			correct_index = 1;
 			credits += (ext_depth(inode)) + 1;
 		}
-		credits += 2 * EXT4_QUOTA_TRANS_BLOCKS(inode->i_sb);
+		credits += EXT4_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb);
 
 		err = ext4_ext_truncate_extend_restart(handle, inode, credits);
 		if (err)
@@ -2378,6 +2495,7 @@ void ext4_ext_init(struct super_block *sb)
 	 */
 
 	if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) {
+#if defined(AGGRESSIVE_TEST) || defined(CHECK_BINSEARCH) || defined(EXTENTS_STATS)
 		printk(KERN_INFO "EXT4-fs: file extents enabled");
 #ifdef AGGRESSIVE_TEST
 		printk(", aggressive tests");
@@ -2389,6 +2507,7 @@ void ext4_ext_init(struct super_block *sb)
 		printk(", stats");
 #endif
 		printk("\n");
+#endif
 #ifdef EXTENTS_STATS
 		spin_lock_init(&EXT4_SB(sb)->s_ext_stats_lock);
 		EXT4_SB(sb)->s_ext_min = 1 << 30;
@@ -2490,7 +2609,6 @@ static int ext4_ext_zeroout(struct inode *inode, struct ext4_extent *ex)
 }
 
 #define EXT4_EXT_ZERO_LEN 7
-
 /*
  * This function is called by ext4_ext_get_blocks() if someone tries to write
  * to an uninitialized extent. It may result in splitting the uninitialized
@@ -2583,7 +2701,8 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
 			ex3->ee_block = cpu_to_le32(iblock);
 			ext4_ext_store_pblock(ex3, newblock);
 			ex3->ee_len = cpu_to_le16(allocated);
-			err = ext4_ext_insert_extent(handle, inode, path, ex3);
+			err = ext4_ext_insert_extent(handle, inode, path,
+							ex3, 0);
 			if (err == -ENOSPC) {
 				err =  ext4_ext_zeroout(inode, &orig_ex);
 				if (err)
@@ -2639,7 +2758,7 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
 		ext4_ext_store_pblock(ex3, newblock + max_blocks);
 		ex3->ee_len = cpu_to_le16(allocated - max_blocks);
 		ext4_ext_mark_uninitialized(ex3);
-		err = ext4_ext_insert_extent(handle, inode, path, ex3);
+		err = ext4_ext_insert_extent(handle, inode, path, ex3, 0);
 		if (err == -ENOSPC) {
 			err =  ext4_ext_zeroout(inode, &orig_ex);
 			if (err)
@@ -2757,7 +2876,7 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
 	err = ext4_ext_dirty(handle, inode, path + depth);
 	goto out;
 insert:
-	err = ext4_ext_insert_extent(handle, inode, path, &newex);
+	err = ext4_ext_insert_extent(handle, inode, path, &newex, 0);
 	if (err == -ENOSPC) {
 		err =  ext4_ext_zeroout(inode, &orig_ex);
 		if (err)
@@ -2785,6 +2904,369 @@ fix_extent_len:
 }
 
 /*
+ * This function is called by ext4_ext_get_blocks() from
+ * ext4_get_blocks_dio_write() when DIO to write
+ * to an uninitialized extent.
+ *
+ * Writing to an uninitized extent may result in splitting the uninitialized
+ * extent into multiple /intialized unintialized extents (up to three)
+ * There are three possibilities:
+ *   a> There is no split required: Entire extent should be uninitialized
+ *   b> Splits in two extents: Write is happening at either end of the extent
+ *   c> Splits in three extents: Somone is writing in middle of the extent
+ *
+ * One of more index blocks maybe needed if the extent tree grow after
+ * the unintialized extent split. To prevent ENOSPC occur at the IO
+ * complete, we need to split the uninitialized extent before DIO submit
+ * the IO. The uninitilized extent called at this time will be split
+ * into three uninitialized extent(at most). After IO complete, the part
+ * being filled will be convert to initialized by the end_io callback function
+ * via ext4_convert_unwritten_extents().
+ *
+ * Returns the size of uninitialized extent to be written on success.
+ */
+static int ext4_split_unwritten_extents(handle_t *handle,
+					struct inode *inode,
+					struct ext4_ext_path *path,
+					ext4_lblk_t iblock,
+					unsigned int max_blocks,
+					int flags)
+{
+	struct ext4_extent *ex, newex, orig_ex;
+	struct ext4_extent *ex1 = NULL;
+	struct ext4_extent *ex2 = NULL;
+	struct ext4_extent *ex3 = NULL;
+	struct ext4_extent_header *eh;
+	ext4_lblk_t ee_block;
+	unsigned int allocated, ee_len, depth;
+	ext4_fsblk_t newblock;
+	int err = 0;
+
+	ext_debug("ext4_split_unwritten_extents: inode %lu,"
+		  "iblock %llu, max_blocks %u\n", inode->i_ino,
+		  (unsigned long long)iblock, max_blocks);
+	depth = ext_depth(inode);
+	eh = path[depth].p_hdr;
+	ex = path[depth].p_ext;
+	ee_block = le32_to_cpu(ex->ee_block);
+	ee_len = ext4_ext_get_actual_len(ex);
+	allocated = ee_len - (iblock - ee_block);
+	newblock = iblock - ee_block + ext_pblock(ex);
+	ex2 = ex;
+	orig_ex.ee_block = ex->ee_block;
+	orig_ex.ee_len   = cpu_to_le16(ee_len);
+	ext4_ext_store_pblock(&orig_ex, ext_pblock(ex));
+
+	/*
+ 	 * If the uninitialized extent begins at the same logical
+ 	 * block where the write begins, and the write completely
+ 	 * covers the extent, then we don't need to split it.
+ 	 */
+	if ((iblock == ee_block) && (allocated <= max_blocks))
+		return allocated;
+
+	err = ext4_ext_get_access(handle, inode, path + depth);
+	if (err)
+		goto out;
+	/* ex1: ee_block to iblock - 1 : uninitialized */
+	if (iblock > ee_block) {
+		ex1 = ex;
+		ex1->ee_len = cpu_to_le16(iblock - ee_block);
+		ext4_ext_mark_uninitialized(ex1);
+		ex2 = &newex;
+	}
+	/*
+	 * for sanity, update the length of the ex2 extent before
+	 * we insert ex3, if ex1 is NULL. This is to avoid temporary
+	 * overlap of blocks.
+	 */
+	if (!ex1 && allocated > max_blocks)
+		ex2->ee_len = cpu_to_le16(max_blocks);
+	/* ex3: to ee_block + ee_len : uninitialised */
+	if (allocated > max_blocks) {
+		unsigned int newdepth;
+		ex3 = &newex;
+		ex3->ee_block = cpu_to_le32(iblock + max_blocks);
+		ext4_ext_store_pblock(ex3, newblock + max_blocks);
+		ex3->ee_len = cpu_to_le16(allocated - max_blocks);
+		ext4_ext_mark_uninitialized(ex3);
+		err = ext4_ext_insert_extent(handle, inode, path, ex3, flags);
+		if (err == -ENOSPC) {
+			err =  ext4_ext_zeroout(inode, &orig_ex);
+			if (err)
+				goto fix_extent_len;
+			/* update the extent length and mark as initialized */
+			ex->ee_block = orig_ex.ee_block;
+			ex->ee_len   = orig_ex.ee_len;
+			ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
+			ext4_ext_dirty(handle, inode, path + depth);
+			/* zeroed the full extent */
+			/* blocks available from iblock */
+			return allocated;
+
+		} else if (err)
+			goto fix_extent_len;
+		/*
+		 * The depth, and hence eh & ex might change
+		 * as part of the insert above.
+		 */
+		newdepth = ext_depth(inode);
+		/*
+		 * update the extent length after successful insert of the
+		 * split extent
+		 */
+		orig_ex.ee_len = cpu_to_le16(ee_len -
+						ext4_ext_get_actual_len(ex3));
+		depth = newdepth;
+		ext4_ext_drop_refs(path);
+		path = ext4_ext_find_extent(inode, iblock, path);
+		if (IS_ERR(path)) {
+			err = PTR_ERR(path);
+			goto out;
+		}
+		eh = path[depth].p_hdr;
+		ex = path[depth].p_ext;
+		if (ex2 != &newex)
+			ex2 = ex;
+
+		err = ext4_ext_get_access(handle, inode, path + depth);
+		if (err)
+			goto out;
+
+		allocated = max_blocks;
+	}
+	/*
+	 * If there was a change of depth as part of the
+	 * insertion of ex3 above, we need to update the length
+	 * of the ex1 extent again here
+	 */
+	if (ex1 && ex1 != ex) {
+		ex1 = ex;
+		ex1->ee_len = cpu_to_le16(iblock - ee_block);
+		ext4_ext_mark_uninitialized(ex1);
+		ex2 = &newex;
+	}
+	/*
+	 * ex2: iblock to iblock + maxblocks-1 : to be direct IO written,
+	 * uninitialised still.
+	 */
+	ex2->ee_block = cpu_to_le32(iblock);
+	ext4_ext_store_pblock(ex2, newblock);
+	ex2->ee_len = cpu_to_le16(allocated);
+	ext4_ext_mark_uninitialized(ex2);
+	if (ex2 != ex)
+		goto insert;
+	/* Mark modified extent as dirty */
+	err = ext4_ext_dirty(handle, inode, path + depth);
+	ext_debug("out here\n");
+	goto out;
+insert:
+	err = ext4_ext_insert_extent(handle, inode, path, &newex, flags);
+	if (err == -ENOSPC) {
+		err =  ext4_ext_zeroout(inode, &orig_ex);
+		if (err)
+			goto fix_extent_len;
+		/* update the extent length and mark as initialized */
+		ex->ee_block = orig_ex.ee_block;
+		ex->ee_len   = orig_ex.ee_len;
+		ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
+		ext4_ext_dirty(handle, inode, path + depth);
+		/* zero out the first half */
+		return allocated;
+	} else if (err)
+		goto fix_extent_len;
+out:
+	ext4_ext_show_leaf(inode, path);
+	return err ? err : allocated;
+
+fix_extent_len:
+	ex->ee_block = orig_ex.ee_block;
+	ex->ee_len   = orig_ex.ee_len;
+	ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
+	ext4_ext_mark_uninitialized(ex);
+	ext4_ext_dirty(handle, inode, path + depth);
+	return err;
+}
+static int ext4_convert_unwritten_extents_endio(handle_t *handle,
+					      struct inode *inode,
+					      struct ext4_ext_path *path)
+{
+	struct ext4_extent *ex;
+	struct ext4_extent_header *eh;
+	int depth;
+	int err = 0;
+	int ret = 0;
+
+	depth = ext_depth(inode);
+	eh = path[depth].p_hdr;
+	ex = path[depth].p_ext;
+
+	err = ext4_ext_get_access(handle, inode, path + depth);
+	if (err)
+		goto out;
+	/* first mark the extent as initialized */
+	ext4_ext_mark_initialized(ex);
+
+	/*
+	 * We have to see if it can be merged with the extent
+	 * on the left.
+	 */
+	if (ex > EXT_FIRST_EXTENT(eh)) {
+		/*
+		 * To merge left, pass "ex - 1" to try_to_merge(),
+		 * since it merges towards right _only_.
+		 */
+		ret = ext4_ext_try_to_merge(inode, path, ex - 1);
+		if (ret) {
+			err = ext4_ext_correct_indexes(handle, inode, path);
+			if (err)
+				goto out;
+			depth = ext_depth(inode);
+			ex--;
+		}
+	}
+	/*
+	 * Try to Merge towards right.
+	 */
+	ret = ext4_ext_try_to_merge(inode, path, ex);
+	if (ret) {
+		err = ext4_ext_correct_indexes(handle, inode, path);
+		if (err)
+			goto out;
+		depth = ext_depth(inode);
+	}
+	/* Mark modified extent as dirty */
+	err = ext4_ext_dirty(handle, inode, path + depth);
+out:
+	ext4_ext_show_leaf(inode, path);
+	return err;
+}
+
+static void unmap_underlying_metadata_blocks(struct block_device *bdev,
+			sector_t block, int count)
+{
+	int i;
+	for (i = 0; i < count; i++)
+                unmap_underlying_metadata(bdev, block + i);
+}
+
+static int
+ext4_ext_handle_uninitialized_extents(handle_t *handle, struct inode *inode,
+			ext4_lblk_t iblock, unsigned int max_blocks,
+			struct ext4_ext_path *path, int flags,
+			unsigned int allocated, struct buffer_head *bh_result,
+			ext4_fsblk_t newblock)
+{
+	int ret = 0;
+	int err = 0;
+	ext4_io_end_t *io = EXT4_I(inode)->cur_aio_dio;
+
+	ext_debug("ext4_ext_handle_uninitialized_extents: inode %lu, logical"
+		  "block %llu, max_blocks %u, flags %d, allocated %u",
+		  inode->i_ino, (unsigned long long)iblock, max_blocks,
+		  flags, allocated);
+	ext4_ext_show_leaf(inode, path);
+
+	/* get_block() before submit the IO, split the extent */
+	if ((flags & EXT4_GET_BLOCKS_PRE_IO)) {
+		ret = ext4_split_unwritten_extents(handle,
+						inode, path, iblock,
+						max_blocks, flags);
+		/*
+		 * Flag the inode(non aio case) or end_io struct (aio case)
+		 * that this IO needs to convertion to written when IO is
+		 * completed
+		 */
+		if (io)
+			io->flag = EXT4_IO_UNWRITTEN;
+		else
+			ext4_set_inode_state(inode, EXT4_STATE_DIO_UNWRITTEN);
+		if (ext4_should_dioread_nolock(inode))
+			set_buffer_uninit(bh_result);
+		goto out;
+	}
+	/* IO end_io complete, convert the filled extent to written */
+	if ((flags & EXT4_GET_BLOCKS_CONVERT)) {
+		ret = ext4_convert_unwritten_extents_endio(handle, inode,
+							path);
+		if (ret >= 0)
+			ext4_update_inode_fsync_trans(handle, inode, 1);
+		goto out2;
+	}
+	/* buffered IO case */
+	/*
+	 * repeat fallocate creation request
+	 * we already have an unwritten extent
+	 */
+	if (flags & EXT4_GET_BLOCKS_UNINIT_EXT)
+		goto map_out;
+
+	/* buffered READ or buffered write_begin() lookup */
+	if ((flags & EXT4_GET_BLOCKS_CREATE) == 0) {
+		/*
+		 * We have blocks reserved already.  We
+		 * return allocated blocks so that delalloc
+		 * won't do block reservation for us.  But
+		 * the buffer head will be unmapped so that
+		 * a read from the block returns 0s.
+		 */
+		set_buffer_unwritten(bh_result);
+		goto out1;
+	}
+
+	/* buffered write, writepage time, convert*/
+	ret = ext4_ext_convert_to_initialized(handle, inode,
+						path, iblock,
+						max_blocks);
+	if (ret >= 0)
+		ext4_update_inode_fsync_trans(handle, inode, 1);
+out:
+	if (ret <= 0) {
+		err = ret;
+		goto out2;
+	} else
+		allocated = ret;
+	set_buffer_new(bh_result);
+	/*
+	 * if we allocated more blocks than requested
+	 * we need to make sure we unmap the extra block
+	 * allocated. The actual needed block will get
+	 * unmapped later when we find the buffer_head marked
+	 * new.
+	 */
+	if (allocated > max_blocks) {
+		unmap_underlying_metadata_blocks(inode->i_sb->s_bdev,
+					newblock + max_blocks,
+					allocated - max_blocks);
+		allocated = max_blocks;
+	}
+
+	/*
+	 * If we have done fallocate with the offset that is already
+	 * delayed allocated, we would have block reservation
+	 * and quota reservation done in the delayed write path.
+	 * But fallocate would have already updated quota and block
+	 * count for this offset. So cancel these reservation
+	 */
+	if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE)
+		ext4_da_update_reserve_space(inode, allocated, 0);
+
+map_out:
+	set_buffer_mapped(bh_result);
+out1:
+	if (allocated > max_blocks)
+		allocated = max_blocks;
+	ext4_ext_show_leaf(inode, path);
+	bh_result->b_bdev = inode->i_sb->s_bdev;
+	bh_result->b_blocknr = newblock;
+out2:
+	if (path) {
+		ext4_ext_drop_refs(path);
+		kfree(path);
+	}
+	return err ? err : allocated;
+}
+/*
  * Block allocation/map/preallocation routine for extents based files
  *
  *
@@ -2809,11 +3291,12 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
 {
 	struct ext4_ext_path *path = NULL;
 	struct ext4_extent_header *eh;
-	struct ext4_extent newex, *ex;
+	struct ext4_extent newex, *ex, *last_ex;
 	ext4_fsblk_t newblock;
 	int err = 0, depth, ret, cache_type;
 	unsigned int allocated = 0;
 	struct ext4_allocation_request ar;
+	ext4_io_end_t *io = EXT4_I(inode)->cur_aio_dio;
 
 	__clear_bit(BH_New, &bh_result->b_state);
 	ext_debug("blocks %u/%u requested for inode %lu\n",
@@ -2860,7 +3343,13 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
 	 * this situation is possible, though, _during_ tree modification;
 	 * this is why assert can't be put in ext4_ext_find_extent()
 	 */
-	BUG_ON(path[depth].p_ext == NULL && depth != 0);
+	if (unlikely(path[depth].p_ext == NULL && depth != 0)) {
+		EXT4_ERROR_INODE(inode, "bad extent address "
+				 "iblock: %d, depth: %d pblock %lld",
+				 iblock, depth, path[depth].p_block);
+		err = -EIO;
+		goto out2;
+	}
 	eh = path[depth].p_hdr;
 
 	ex = path[depth].p_ext;
@@ -2875,7 +3364,7 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
 		 */
 		ee_len = ext4_ext_get_actual_len(ex);
 		/* if found extent covers block, simply return it */
-		if (iblock >= ee_block && iblock < ee_block + ee_len) {
+		if (in_range(iblock, ee_block, ee_len)) {
 			newblock = iblock - ee_block + ee_start;
 			/* number of remaining blocks in the extent */
 			allocated = ee_len - (iblock - ee_block);
@@ -2889,33 +3378,10 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
 							EXT4_EXT_CACHE_EXTENT);
 				goto out;
 			}
-			if (flags & EXT4_GET_BLOCKS_UNINIT_EXT)
-				goto out;
-			if ((flags & EXT4_GET_BLOCKS_CREATE) == 0) {
-				if (allocated > max_blocks)
-					allocated = max_blocks;
-				/*
-				 * We have blocks reserved already.  We
-				 * return allocated blocks so that delalloc
-				 * won't do block reservation for us.  But
-				 * the buffer head will be unmapped so that
-				 * a read from the block returns 0s.
-				 */
-				set_buffer_unwritten(bh_result);
-				bh_result->b_bdev = inode->i_sb->s_bdev;
-				bh_result->b_blocknr = newblock;
-				goto out2;
-			}
-
-			ret = ext4_ext_convert_to_initialized(handle, inode,
-								path, iblock,
-								max_blocks);
-			if (ret <= 0) {
-				err = ret;
-				goto out2;
-			} else
-				allocated = ret;
-			goto outnew;
+			ret = ext4_ext_handle_uninitialized_extents(handle,
+					inode, iblock, max_blocks, path,
+					flags, allocated, bh_result, newblock);
+			return ret;
 		}
 	}
 
@@ -2986,29 +3452,75 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
 	/* try to insert new extent into found leaf and return */
 	ext4_ext_store_pblock(&newex, newblock);
 	newex.ee_len = cpu_to_le16(ar.len);
-	if (flags & EXT4_GET_BLOCKS_UNINIT_EXT)  /* Mark uninitialized */
+	/* Mark uninitialized */
+	if (flags & EXT4_GET_BLOCKS_UNINIT_EXT){
 		ext4_ext_mark_uninitialized(&newex);
-	err = ext4_ext_insert_extent(handle, inode, path, &newex);
+		/*
+		 * io_end structure was created for every IO write to an
+		 * uninitialized extent. To avoid unecessary conversion,
+		 * here we flag the IO that really needs the conversion.
+		 * For non asycn direct IO case, flag the inode state
+		 * that we need to perform convertion when IO is done.
+		 */
+		if ((flags & EXT4_GET_BLOCKS_PRE_IO)) {
+			if (io)
+				io->flag = EXT4_IO_UNWRITTEN;
+			else
+				ext4_set_inode_state(inode,
+						     EXT4_STATE_DIO_UNWRITTEN);
+		}
+		if (ext4_should_dioread_nolock(inode))
+			set_buffer_uninit(bh_result);
+	}
+
+	if (unlikely(EXT4_I(inode)->i_flags & EXT4_EOFBLOCKS_FL)) {
+		if (unlikely(!eh->eh_entries)) {
+			EXT4_ERROR_INODE(inode,
+					 "eh->eh_entries == 0 ee_block %d",
+					 ex->ee_block);
+			err = -EIO;
+			goto out2;
+		}
+		last_ex = EXT_LAST_EXTENT(eh);
+		if (iblock + ar.len > le32_to_cpu(last_ex->ee_block)
+		    + ext4_ext_get_actual_len(last_ex))
+			EXT4_I(inode)->i_flags &= ~EXT4_EOFBLOCKS_FL;
+	}
+	err = ext4_ext_insert_extent(handle, inode, path, &newex, flags);
 	if (err) {
 		/* 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_discard_preallocations(inode);
-		ext4_free_blocks(handle, inode, ext_pblock(&newex),
-					ext4_ext_get_actual_len(&newex), 0);
+		ext4_free_blocks(handle, inode, 0, ext_pblock(&newex),
+				 ext4_ext_get_actual_len(&newex), 0);
 		goto out2;
 	}
 
 	/* previous routine could use block we allocated */
 	newblock = ext_pblock(&newex);
 	allocated = ext4_ext_get_actual_len(&newex);
-outnew:
+	if (allocated > max_blocks)
+		allocated = max_blocks;
 	set_buffer_new(bh_result);
 
-	/* Cache only when it is _not_ an uninitialized extent */
-	if ((flags & EXT4_GET_BLOCKS_UNINIT_EXT) == 0)
+	/*
+	 * Update reserved blocks/metadata blocks after successful
+	 * block allocation which had been deferred till now.
+	 */
+	if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE)
+		ext4_da_update_reserve_space(inode, allocated, 1);
+
+	/*
+	 * Cache the extent and update transaction to commit on fdatasync only
+	 * when it is _not_ an uninitialized extent.
+	 */
+	if ((flags & EXT4_GET_BLOCKS_UNINIT_EXT) == 0) {
 		ext4_ext_put_in_cache(inode, iblock, allocated, newblock,
 						EXT4_EXT_CACHE_EXTENT);
+		ext4_update_inode_fsync_trans(handle, inode, 1);
+	} else
+		ext4_update_inode_fsync_trans(handle, inode, 0);
 out:
 	if (allocated > max_blocks)
 		allocated = max_blocks;
@@ -3107,6 +3619,13 @@ static void ext4_falloc_update_inode(struct inode *inode,
 			i_size_write(inode, new_size);
 		if (new_size > EXT4_I(inode)->i_disksize)
 			ext4_update_i_disksize(inode, new_size);
+	} else {
+		/*
+		 * Mark that we allocate beyond EOF so the subsequent truncate
+		 * can proceed even if the new size is the same as i_size.
+		 */
+		if (new_size > i_size_read(inode))
+			EXT4_I(inode)->i_flags |= EXT4_EOFBLOCKS_FL;
 	}
 
 }
@@ -3201,6 +3720,64 @@ retry:
 }
 
 /*
+ * This function convert a range of blocks to written extents
+ * The caller of this function will pass the start offset and the size.
+ * all unwritten extents within this range will be converted to
+ * written extents.
+ *
+ * This function is called from the direct IO end io call back
+ * function, to convert the fallocated extents after IO is completed.
+ * Returns 0 on success.
+ */
+int ext4_convert_unwritten_extents(struct inode *inode, loff_t offset,
+				    ssize_t len)
+{
+	handle_t *handle;
+	ext4_lblk_t block;
+	unsigned int max_blocks;
+	int ret = 0;
+	int ret2 = 0;
+	struct buffer_head map_bh;
+	unsigned int credits, blkbits = inode->i_blkbits;
+
+	block = offset >> blkbits;
+	/*
+	 * We can't just convert len to max_blocks because
+	 * If blocksize = 4096 offset = 3072 and len = 2048
+	 */
+	max_blocks = (EXT4_BLOCK_ALIGN(len + offset, blkbits) >> blkbits)
+							- block;
+	/*
+	 * credits to insert 1 extent into extent tree
+	 */
+	credits = ext4_chunk_trans_blocks(inode, max_blocks);
+	while (ret >= 0 && ret < max_blocks) {
+		block = block + ret;
+		max_blocks = max_blocks - ret;
+		handle = ext4_journal_start(inode, credits);
+		if (IS_ERR(handle)) {
+			ret = PTR_ERR(handle);
+			break;
+		}
+		map_bh.b_state = 0;
+		ret = ext4_get_blocks(handle, inode, block,
+				      max_blocks, &map_bh,
+				      EXT4_GET_BLOCKS_IO_CONVERT_EXT);
+		if (ret <= 0) {
+			WARN_ON(ret <= 0);
+			printk(KERN_ERR "%s: ext4_ext_get_blocks "
+				    "returned error inode#%lu, block=%u, "
+				    "max_blocks=%u", __func__,
+				    inode->i_ino, block, max_blocks);
+		}
+		ext4_mark_inode_dirty(handle, inode);
+		ret2 = ext4_journal_stop(handle);
+		if (ret <= 0 || ret2 )
+			break;
+	}
+	return ret > 0 ? ret2 : ret;
+}
+/*
  * Callback function called for each extent to gather FIEMAP information.
  */
 static int ext4_ext_fiemap_cb(struct inode *inode, struct ext4_ext_path *path,
@@ -3289,7 +3866,7 @@ static int ext4_xattr_fiemap(struct inode *inode,
 	int error = 0;
 
 	/* in-inode? */
-	if (EXT4_I(inode)->i_state & EXT4_STATE_XATTR) {
+	if (ext4_test_inode_state(inode, EXT4_STATE_XATTR)) {
 		struct ext4_iloc iloc;
 		int offset;	/* offset of xattr in inode */
 
@@ -3317,7 +3894,6 @@ int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
 		__u64 start, __u64 len)
 {
 	ext4_lblk_t start_blk;
-	ext4_lblk_t len_blks;
 	int error = 0;
 
 	/* fallback to generic here if not in extents fmt */
@@ -3331,17 +3907,21 @@ int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
 	if (fieinfo->fi_flags & FIEMAP_FLAG_XATTR) {
 		error = ext4_xattr_fiemap(inode, fieinfo);
 	} else {
+		ext4_lblk_t len_blks;
+		__u64 last_blk;
+
 		start_blk = start >> inode->i_sb->s_blocksize_bits;
-		len_blks = len >> inode->i_sb->s_blocksize_bits;
+		last_blk = (start + len - 1) >> inode->i_sb->s_blocksize_bits;
+		if (last_blk >= EXT_MAX_BLOCK)
+			last_blk = EXT_MAX_BLOCK-1;
+		len_blks = ((ext4_lblk_t) last_blk) - start_blk + 1;
 
 		/*
 		 * Walk the extent tree gathering extent information.
 		 * ext4_ext_fiemap_cb will push extents back to user.
 		 */
-		down_read(&EXT4_I(inode)->i_data_sem);
 		error = ext4_ext_walk_space(inode, start_blk, len_blks,
 					  ext4_ext_fiemap_cb, fieinfo);
-		up_read(&EXT4_I(inode)->i_data_sem);
 	}
 
 	return error;