1 files changed, 333 insertions, 95 deletions

diff --git a/kernel/fs/ext4/extents.c b/kernel/fs/ext4/extents.c
index 87ba10d1d..551353b1b 100644
--- a/kernel/fs/ext4/extents.c
+++ b/kernel/fs/ext4/extents.c
@@ -39,6 +39,7 @@
 #include <linux/slab.h>
 #include <asm/uaccess.h>
 #include <linux/fiemap.h>
+#include <linux/backing-dev.h>
 #include "ext4_jbd2.h"
 #include "ext4_extents.h"
 #include "xattr.h"
@@ -441,7 +442,7 @@ static int __ext4_ext_check(const char *function, unsigned int line,
 			    int depth, ext4_fsblk_t pblk)
 {
 	const char *error_msg;
-	int max = 0;
+	int max = 0, err = -EFSCORRUPTED;
 
 	if (unlikely(eh->eh_magic != EXT4_EXT_MAGIC)) {
 		error_msg = "invalid magic";
@@ -472,6 +473,7 @@ static int __ext4_ext_check(const char *function, unsigned int line,
 	if (ext_depth(inode) != depth &&
 	    !ext4_extent_block_csum_verify(inode, eh)) {
 		error_msg = "extent tree corrupted";
+		err = -EFSBADCRC;
 		goto corrupted;
 	}
 	return 0;
@@ -484,7 +486,7 @@ corrupted:
 			 le16_to_cpu(eh->eh_magic),
 			 le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max),
 			 max, le16_to_cpu(eh->eh_depth), depth);
-	return -EIO;
+	return err;
 }
 
 #define ext4_ext_check(inode, eh, depth, pblk)			\
@@ -898,7 +900,7 @@ ext4_find_extent(struct inode *inode, ext4_lblk_t block,
 
 		bh = read_extent_tree_block(inode, path[ppos].p_block, --i,
 					    flags);
-		if (unlikely(IS_ERR(bh))) {
+		if (IS_ERR(bh)) {
 			ret = PTR_ERR(bh);
 			goto err;
 		}
@@ -909,7 +911,7 @@ ext4_find_extent(struct inode *inode, ext4_lblk_t block,
 			put_bh(bh);
 			EXT4_ERROR_INODE(inode,
 					 "ppos %d > depth %d", ppos, depth);
-			ret = -EIO;
+			ret = -EFSCORRUPTED;
 			goto err;
 		}
 		path[ppos].p_bh = bh;
@@ -958,7 +960,7 @@ static int ext4_ext_insert_index(handle_t *handle, struct inode *inode,
 		EXT4_ERROR_INODE(inode,
 				 "logical %d == ei_block %d!",
 				 logical, le32_to_cpu(curp->p_idx->ei_block));
-		return -EIO;
+		return -EFSCORRUPTED;
 	}
 
 	if (unlikely(le16_to_cpu(curp->p_hdr->eh_entries)
@@ -967,7 +969,7 @@ static int ext4_ext_insert_index(handle_t *handle, struct inode *inode,
 				 "eh_entries %d >= eh_max %d!",
 				 le16_to_cpu(curp->p_hdr->eh_entries),
 				 le16_to_cpu(curp->p_hdr->eh_max));
-		return -EIO;
+		return -EFSCORRUPTED;
 	}
 
 	if (logical > le32_to_cpu(curp->p_idx->ei_block)) {
@@ -991,7 +993,7 @@ static int ext4_ext_insert_index(handle_t *handle, struct inode *inode,
 
 	if (unlikely(ix > EXT_MAX_INDEX(curp->p_hdr))) {
 		EXT4_ERROR_INODE(inode, "ix > EXT_MAX_INDEX!");
-		return -EIO;
+		return -EFSCORRUPTED;
 	}
 
 	ix->ei_block = cpu_to_le32(logical);
@@ -1000,7 +1002,7 @@ static int ext4_ext_insert_index(handle_t *handle, struct inode *inode,
 
 	if (unlikely(ix > EXT_LAST_INDEX(curp->p_hdr))) {
 		EXT4_ERROR_INODE(inode, "ix > EXT_LAST_INDEX!");
-		return -EIO;
+		return -EFSCORRUPTED;
 	}
 
 	err = ext4_ext_dirty(handle, inode, curp);
@@ -1041,7 +1043,7 @@ static int ext4_ext_split(handle_t *handle, struct inode *inode,
 	 * border from split point */
 	if (unlikely(path[depth].p_ext > EXT_MAX_EXTENT(path[depth].p_hdr))) {
 		EXT4_ERROR_INODE(inode, "p_ext > EXT_MAX_EXTENT!");
-		return -EIO;
+		return -EFSCORRUPTED;
 	}
 	if (path[depth].p_ext != EXT_MAX_EXTENT(path[depth].p_hdr)) {
 		border = path[depth].p_ext[1].ee_block;
@@ -1085,7 +1087,7 @@ static int ext4_ext_split(handle_t *handle, struct inode *inode,
 	newblock = ablocks[--a];
 	if (unlikely(newblock == 0)) {
 		EXT4_ERROR_INODE(inode, "newblock == 0!");
-		err = -EIO;
+		err = -EFSCORRUPTED;
 		goto cleanup;
 	}
 	bh = sb_getblk_gfp(inode->i_sb, newblock, __GFP_MOVABLE | GFP_NOFS);
@@ -1111,7 +1113,7 @@ static int ext4_ext_split(handle_t *handle, struct inode *inode,
 		EXT4_ERROR_INODE(inode, "eh_entries %d != eh_max %d!",
 				 path[depth].p_hdr->eh_entries,
 				 path[depth].p_hdr->eh_max);
-		err = -EIO;
+		err = -EFSCORRUPTED;
 		goto cleanup;
 	}
 	/* start copy from next extent */
@@ -1150,7 +1152,7 @@ static int ext4_ext_split(handle_t *handle, struct inode *inode,
 	k = depth - at - 1;
 	if (unlikely(k < 0)) {
 		EXT4_ERROR_INODE(inode, "k %d < 0!", k);
-		err = -EIO;
+		err = -EFSCORRUPTED;
 		goto cleanup;
 	}
 	if (k)
@@ -1190,7 +1192,7 @@ static int ext4_ext_split(handle_t *handle, struct inode *inode,
 			EXT4_ERROR_INODE(inode,
 					 "EXT_MAX_INDEX != EXT_LAST_INDEX ee_block %d!",
 					 le32_to_cpu(path[i].p_ext->ee_block));
-			err = -EIO;
+			err = -EFSCORRUPTED;
 			goto cleanup;
 		}
 		/* start copy indexes */
@@ -1424,7 +1426,7 @@ static int ext4_ext_search_left(struct inode *inode,
 
 	if (unlikely(path == NULL)) {
 		EXT4_ERROR_INODE(inode, "path == NULL *logical %d!", *logical);
-		return -EIO;
+		return -EFSCORRUPTED;
 	}
 	depth = path->p_depth;
 	*phys = 0;
@@ -1443,7 +1445,7 @@ static int ext4_ext_search_left(struct inode *inode,
 			EXT4_ERROR_INODE(inode,
 					 "EXT_FIRST_EXTENT != ex *logical %d ee_block %d!",
 					 *logical, le32_to_cpu(ex->ee_block));
-			return -EIO;
+			return -EFSCORRUPTED;
 		}
 		while (--depth >= 0) {
 			ix = path[depth].p_idx;
@@ -1454,7 +1456,7 @@ static int ext4_ext_search_left(struct inode *inode,
 				  EXT_FIRST_INDEX(path[depth].p_hdr) != NULL ?
 		le32_to_cpu(EXT_FIRST_INDEX(path[depth].p_hdr)->ei_block) : 0,
 				  depth);
-				return -EIO;
+				return -EFSCORRUPTED;
 			}
 		}
 		return 0;
@@ -1464,7 +1466,7 @@ static int ext4_ext_search_left(struct inode *inode,
 		EXT4_ERROR_INODE(inode,
 				 "logical %d < ee_block %d + ee_len %d!",
 				 *logical, le32_to_cpu(ex->ee_block), ee_len);
-		return -EIO;
+		return -EFSCORRUPTED;
 	}
 
 	*logical = le32_to_cpu(ex->ee_block) + ee_len - 1;
@@ -1494,7 +1496,7 @@ static int ext4_ext_search_right(struct inode *inode,
 
 	if (unlikely(path == NULL)) {
 		EXT4_ERROR_INODE(inode, "path == NULL *logical %d!", *logical);
-		return -EIO;
+		return -EFSCORRUPTED;
 	}
 	depth = path->p_depth;
 	*phys = 0;
@@ -1513,7 +1515,7 @@ static int ext4_ext_search_right(struct inode *inode,
 			EXT4_ERROR_INODE(inode,
 					 "first_extent(path[%d].p_hdr) != ex",
 					 depth);
-			return -EIO;
+			return -EFSCORRUPTED;
 		}
 		while (--depth >= 0) {
 			ix = path[depth].p_idx;
@@ -1521,7 +1523,7 @@ static int ext4_ext_search_right(struct inode *inode,
 				EXT4_ERROR_INODE(inode,
 						 "ix != EXT_FIRST_INDEX *logical %d!",
 						 *logical);
-				return -EIO;
+				return -EFSCORRUPTED;
 			}
 		}
 		goto found_extent;
@@ -1531,7 +1533,7 @@ static int ext4_ext_search_right(struct inode *inode,
 		EXT4_ERROR_INODE(inode,
 				 "logical %d < ee_block %d + ee_len %d!",
 				 *logical, le32_to_cpu(ex->ee_block), ee_len);
-		return -EIO;
+		return -EFSCORRUPTED;
 	}
 
 	if (ex != EXT_LAST_EXTENT(path[depth].p_hdr)) {
@@ -1669,7 +1671,7 @@ static int ext4_ext_correct_indexes(handle_t *handle, struct inode *inode,
 	if (unlikely(ex == NULL || eh == NULL)) {
 		EXT4_ERROR_INODE(inode,
 				 "ex %p == NULL or eh %p == NULL", ex, eh);
-		return -EIO;
+		return -EFSCORRUPTED;
 	}
 
 	if (depth == 0) {
@@ -1937,14 +1939,14 @@ int ext4_ext_insert_extent(handle_t *handle, struct inode *inode,
 		mb_flags |= EXT4_MB_DELALLOC_RESERVED;
 	if (unlikely(ext4_ext_get_actual_len(newext) == 0)) {
 		EXT4_ERROR_INODE(inode, "ext4_ext_get_actual_len(newext) == 0");
-		return -EIO;
+		return -EFSCORRUPTED;
 	}
 	depth = ext_depth(inode);
 	ex = path[depth].p_ext;
 	eh = path[depth].p_hdr;
 	if (unlikely(path[depth].p_hdr == NULL)) {
 		EXT4_ERROR_INODE(inode, "path[%d].p_hdr == NULL", depth);
-		return -EIO;
+		return -EFSCORRUPTED;
 	}
 
 	/* try to insert block into found extent and return */
@@ -2171,7 +2173,7 @@ static int ext4_fill_fiemap_extents(struct inode *inode,
 		if (unlikely(path[depth].p_hdr == NULL)) {
 			up_read(&EXT4_I(inode)->i_data_sem);
 			EXT4_ERROR_INODE(inode, "path[%d].p_hdr == NULL", depth);
-			err = -EIO;
+			err = -EFSCORRUPTED;
 			break;
 		}
 		ex = path[depth].p_ext;
@@ -2240,7 +2242,7 @@ static int ext4_fill_fiemap_extents(struct inode *inode,
 
 		if (unlikely(es.es_len == 0)) {
 			EXT4_ERROR_INODE(inode, "es.es_len == 0");
-			err = -EIO;
+			err = -EFSCORRUPTED;
 			break;
 		}
 
@@ -2263,7 +2265,7 @@ static int ext4_fill_fiemap_extents(struct inode *inode,
 						 "next extent == %u, next "
 						 "delalloc extent = %u",
 						 next, next_del);
-				err = -EIO;
+				err = -EFSCORRUPTED;
 				break;
 			}
 		}
@@ -2362,7 +2364,7 @@ static int ext4_ext_rm_idx(handle_t *handle, struct inode *inode,
 	leaf = ext4_idx_pblock(path->p_idx);
 	if (unlikely(path->p_hdr->eh_entries == 0)) {
 		EXT4_ERROR_INODE(inode, "path->p_hdr->eh_entries == 0");
-		return -EIO;
+		return -EFSCORRUPTED;
 	}
 	err = ext4_ext_get_access(handle, inode, path);
 	if (err)
@@ -2611,7 +2613,7 @@ ext4_ext_rm_leaf(handle_t *handle, struct inode *inode,
 	eh = path[depth].p_hdr;
 	if (unlikely(path[depth].p_hdr == NULL)) {
 		EXT4_ERROR_INODE(inode, "path[%d].p_hdr == NULL", depth);
-		return -EIO;
+		return -EFSCORRUPTED;
 	}
 	/* find where to start removing */
 	ex = path[depth].p_ext;
@@ -2665,7 +2667,7 @@ ext4_ext_rm_leaf(handle_t *handle, struct inode *inode,
 					 "on extent %u:%u",
 					 start, end, ex_ee_block,
 					 ex_ee_block + ex_ee_len - 1);
-			err = -EIO;
+			err = -EFSCORRUPTED;
 			goto out;
 		} else if (a != ex_ee_block) {
 			/* remove tail of the extent */
@@ -2840,7 +2842,7 @@ again:
 				EXT4_ERROR_INODE(inode,
 						 "path[%d].p_hdr == NULL",
 						 depth);
-				err = -EIO;
+				err = -EFSCORRUPTED;
 			}
 			goto out;
 		}
@@ -2919,7 +2921,7 @@ again:
 		i = 0;
 
 		if (ext4_ext_check(inode, path[0].p_hdr, depth, 0)) {
-			err = -EIO;
+			err = -EFSCORRUPTED;
 			goto out;
 		}
 	}
@@ -2977,7 +2979,7 @@ again:
 			 * Should be a no-op if we did IO above. */
 			cond_resched();
 			if (WARN_ON(i + 1 > depth)) {
-				err = -EIO;
+				err = -EFSCORRUPTED;
 				break;
 			}
 			path[i + 1].p_bh = bh;
@@ -3053,7 +3055,7 @@ void ext4_ext_init(struct super_block *sb)
 	 * possible initialization would be here
 	 */
 
-	if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) {
+	if (ext4_has_feature_extents(sb)) {
 #if defined(AGGRESSIVE_TEST) || defined(CHECK_BINSEARCH) || defined(EXTENTS_STATS)
 		printk(KERN_INFO "EXT4-fs: file extents enabled"
 #ifdef AGGRESSIVE_TEST
@@ -3080,7 +3082,7 @@ void ext4_ext_init(struct super_block *sb)
  */
 void ext4_ext_release(struct super_block *sb)
 {
-	if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS))
+	if (!ext4_has_feature_extents(sb))
 		return;
 
 #ifdef EXTENTS_STATS
@@ -3344,7 +3346,7 @@ static int ext4_split_extent(handle_t *handle,
 	if (!ex) {
 		EXT4_ERROR_INODE(inode, "unexpected hole at %lu",
 				 (unsigned long) map->m_lblk);
-		return -EIO;
+		return -EFSCORRUPTED;
 	}
 	unwritten = ext4_ext_is_unwritten(ex);
 	split_flag1 = 0;
@@ -3557,6 +3559,9 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
 		max_zeroout = sbi->s_extent_max_zeroout_kb >>
 			(inode->i_sb->s_blocksize_bits - 10);
 
+	if (ext4_encrypted_inode(inode))
+		max_zeroout = 0;
+
 	/* If extent is less than s_max_zeroout_kb, zeroout directly */
 	if (max_zeroout && (ee_len <= max_zeroout)) {
 		err = ext4_ext_zeroout(inode, ex);
@@ -3969,7 +3974,7 @@ convert_initialized_extent(handle_t *handle, struct inode *inode,
 		if (!ex) {
 			EXT4_ERROR_INODE(inode, "unexpected hole at %lu",
 					 (unsigned long) map->m_lblk);
-			return -EIO;
+			return -EFSCORRUPTED;
 		}
 	}
 
@@ -4307,7 +4312,7 @@ int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
 				 "lblock: %lu, depth: %d pblock %lld",
 				 (unsigned long) map->m_lblk, depth,
 				 path[depth].p_block);
-		err = -EIO;
+		err = -EFSCORRUPTED;
 		goto out2;
 	}
 
@@ -4456,6 +4461,8 @@ int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
 		ar.flags |= EXT4_MB_HINT_NOPREALLOC;
 	if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE)
 		ar.flags |= EXT4_MB_DELALLOC_RESERVED;
+	if (flags & EXT4_GET_BLOCKS_METADATA_NOFAIL)
+		ar.flags |= EXT4_MB_USE_RESERVED;
 	newblock = ext4_mb_new_blocks(handle, &ar, &err);
 	if (!newblock)
 		goto out2;
@@ -4663,6 +4670,7 @@ static int ext4_alloc_file_blocks(struct file *file, ext4_lblk_t offset,
 	int ret = 0;
 	int ret2 = 0;
 	int retries = 0;
+	int depth = 0;
 	struct ext4_map_blocks map;
 	unsigned int credits;
 	loff_t epos;
@@ -4677,13 +4685,32 @@ static int ext4_alloc_file_blocks(struct file *file, ext4_lblk_t offset,
 	if (len <= EXT_UNWRITTEN_MAX_LEN)
 		flags |= EXT4_GET_BLOCKS_NO_NORMALIZE;
 
+	/* Wait all existing dio workers, newcomers will block on i_mutex */
+	ext4_inode_block_unlocked_dio(inode);
+	inode_dio_wait(inode);
+
 	/*
 	 * credits to insert 1 extent into extent tree
 	 */
 	credits = ext4_chunk_trans_blocks(inode, len);
+	/*
+	 * We can only call ext_depth() on extent based inodes
+	 */
+	if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
+		depth = ext_depth(inode);
+	else
+		depth = -1;
 
 retry:
 	while (ret >= 0 && len) {
+		/*
+		 * Recalculate credits when extent tree depth changes.
+		 */
+		if (depth >= 0 && depth != ext_depth(inode)) {
+			credits = ext4_chunk_trans_blocks(inode, len);
+			depth = ext_depth(inode);
+		}
+
 		handle = ext4_journal_start(inode, EXT4_HT_MAP_BLOCKS,
 					    credits);
 		if (IS_ERR(handle)) {
@@ -4725,6 +4752,8 @@ retry:
 		goto retry;
 	}
 
+	ext4_inode_resume_unlocked_dio(inode);
+
 	return ret > 0 ? ret2 : ret;
 }
 
@@ -4912,12 +4941,14 @@ long ext4_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
 	 * bug we should fix....
 	 */
 	if (ext4_encrypted_inode(inode) &&
-	    (mode & (FALLOC_FL_COLLAPSE_RANGE | FALLOC_FL_ZERO_RANGE)))
+	    (mode & (FALLOC_FL_COLLAPSE_RANGE | FALLOC_FL_INSERT_RANGE |
+		     FALLOC_FL_ZERO_RANGE)))
 		return -EOPNOTSUPP;
 
 	/* Return error if mode is not supported */
 	if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE |
-		     FALLOC_FL_COLLAPSE_RANGE | FALLOC_FL_ZERO_RANGE))
+		     FALLOC_FL_COLLAPSE_RANGE | FALLOC_FL_ZERO_RANGE |
+		     FALLOC_FL_INSERT_RANGE))
 		return -EOPNOTSUPP;
 
 	if (mode & FALLOC_FL_PUNCH_HOLE)
@@ -4930,6 +4961,9 @@ long ext4_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
 	if (mode & FALLOC_FL_COLLAPSE_RANGE)
 		return ext4_collapse_range(inode, offset, len);
 
+	if (mode & FALLOC_FL_INSERT_RANGE)
+		return ext4_insert_range(inode, offset, len);
+
 	if (mode & FALLOC_FL_ZERO_RANGE)
 		return ext4_zero_range(file, offset, len, mode);
 
@@ -5224,13 +5258,13 @@ ext4_access_path(handle_t *handle, struct inode *inode,
 /*
  * ext4_ext_shift_path_extents:
  * Shift the extents of a path structure lying between path[depth].p_ext
- * and EXT_LAST_EXTENT(path[depth].p_hdr) downwards, by subtracting shift
- * from starting block for each extent.
+ * and EXT_LAST_EXTENT(path[depth].p_hdr), by @shift blocks. @SHIFT tells
+ * if it is right shift or left shift operation.
  */
 static int
 ext4_ext_shift_path_extents(struct ext4_ext_path *path, ext4_lblk_t shift,
 			    struct inode *inode, handle_t *handle,
-			    ext4_lblk_t *start)
+			    enum SHIFT_DIRECTION SHIFT)
 {
 	int depth, err = 0;
 	struct ext4_extent *ex_start, *ex_last;
@@ -5241,7 +5275,7 @@ ext4_ext_shift_path_extents(struct ext4_ext_path *path, ext4_lblk_t shift,
 		if (depth == path->p_depth) {
 			ex_start = path[depth].p_ext;
 			if (!ex_start)
-				return -EIO;
+				return -EFSCORRUPTED;
 
 			ex_last = EXT_LAST_EXTENT(path[depth].p_hdr);
 
@@ -5252,19 +5286,25 @@ ext4_ext_shift_path_extents(struct ext4_ext_path *path, ext4_lblk_t shift,
 			if (ex_start == EXT_FIRST_EXTENT(path[depth].p_hdr))
 				update = 1;
 
-			*start = le32_to_cpu(ex_last->ee_block) +
-				ext4_ext_get_actual_len(ex_last);
-
 			while (ex_start <= ex_last) {
-				le32_add_cpu(&ex_start->ee_block, -shift);
-				/* Try to merge to the left. */
-				if ((ex_start >
-				     EXT_FIRST_EXTENT(path[depth].p_hdr)) &&
-				    ext4_ext_try_to_merge_right(inode,
-							path, ex_start - 1))
+				if (SHIFT == SHIFT_LEFT) {
+					le32_add_cpu(&ex_start->ee_block,
+						-shift);
+					/* Try to merge to the left. */
+					if ((ex_start >
+					    EXT_FIRST_EXTENT(path[depth].p_hdr))
+					    &&
+					    ext4_ext_try_to_merge_right(inode,
+					    path, ex_start - 1))
+						ex_last--;
+					else
+						ex_start++;
+				} else {
+					le32_add_cpu(&ex_last->ee_block, shift);
+					ext4_ext_try_to_merge_right(inode, path,
+						ex_last);
 					ex_last--;
-				else
-					ex_start++;
+				}
 			}
 			err = ext4_ext_dirty(handle, inode, path + depth);
 			if (err)
@@ -5279,7 +5319,10 @@ ext4_ext_shift_path_extents(struct ext4_ext_path *path, ext4_lblk_t shift,
 		if (err)
 			goto out;
 
-		le32_add_cpu(&path[depth].p_idx->ei_block, -shift);
+		if (SHIFT == SHIFT_LEFT)
+			le32_add_cpu(&path[depth].p_idx->ei_block, -shift);
+		else
+			le32_add_cpu(&path[depth].p_idx->ei_block, shift);
 		err = ext4_ext_dirty(handle, inode, path + depth);
 		if (err)
 			goto out;
@@ -5297,19 +5340,20 @@ out:
 
 /*
  * ext4_ext_shift_extents:
- * All the extents which lies in the range from start to the last allocated
- * block for the file are shifted downwards by shift blocks.
+ * All the extents which lies in the range from @start to the last allocated
+ * block for the @inode are shifted either towards left or right (depending
+ * upon @SHIFT) by @shift blocks.
  * On success, 0 is returned, error otherwise.
  */
 static int
 ext4_ext_shift_extents(struct inode *inode, handle_t *handle,
-		       ext4_lblk_t start, ext4_lblk_t shift)
+		       ext4_lblk_t start, ext4_lblk_t shift,
+		       enum SHIFT_DIRECTION SHIFT)
 {
 	struct ext4_ext_path *path;
 	int ret = 0, depth;
 	struct ext4_extent *extent;
-	ext4_lblk_t stop_block;
-	ext4_lblk_t ex_start, ex_end;
+	ext4_lblk_t stop, *iterator, ex_start, ex_end;
 
 	/* Let path point to the last extent */
 	path = ext4_find_extent(inode, EXT_MAX_BLOCKS - 1, NULL, 0);
@@ -5321,58 +5365,84 @@ ext4_ext_shift_extents(struct inode *inode, handle_t *handle,
 	if (!extent)
 		goto out;
 
-	stop_block = le32_to_cpu(extent->ee_block) +
+	stop = le32_to_cpu(extent->ee_block) +
 			ext4_ext_get_actual_len(extent);
 
-	/* Nothing to shift, if hole is at the end of file */
-	if (start >= stop_block)
-		goto out;
+       /*
+	 * In case of left shift, Don't start shifting extents until we make
+	 * sure the hole is big enough to accommodate the shift.
+	*/
+	if (SHIFT == SHIFT_LEFT) {
+		path = ext4_find_extent(inode, start - 1, &path, 0);
+		if (IS_ERR(path))
+			return PTR_ERR(path);
+		depth = path->p_depth;
+		extent =  path[depth].p_ext;
+		if (extent) {
+			ex_start = le32_to_cpu(extent->ee_block);
+			ex_end = le32_to_cpu(extent->ee_block) +
+				ext4_ext_get_actual_len(extent);
+		} else {
+			ex_start = 0;
+			ex_end = 0;
+		}
 
-	/*
-	 * Don't start shifting extents until we make sure the hole is big
-	 * enough to accomodate the shift.
-	 */
-	path = ext4_find_extent(inode, start - 1, &path, 0);
-	if (IS_ERR(path))
-		return PTR_ERR(path);
-	depth = path->p_depth;
-	extent =  path[depth].p_ext;
-	if (extent) {
-		ex_start = le32_to_cpu(extent->ee_block);
-		ex_end = le32_to_cpu(extent->ee_block) +
-			ext4_ext_get_actual_len(extent);
-	} else {
-		ex_start = 0;
-		ex_end = 0;
+		if ((start == ex_start && shift > ex_start) ||
+		    (shift > start - ex_end)) {
+			ext4_ext_drop_refs(path);
+			kfree(path);
+			return -EINVAL;
+		}
 	}
 
-	if ((start == ex_start && shift > ex_start) ||
-	    (shift > start - ex_end))
-		return -EINVAL;
+	/*
+	 * In case of left shift, iterator points to start and it is increased
+	 * till we reach stop. In case of right shift, iterator points to stop
+	 * and it is decreased till we reach start.
+	 */
+	if (SHIFT == SHIFT_LEFT)
+		iterator = &start;
+	else
+		iterator = &stop;
 
 	/* Its safe to start updating extents */
-	while (start < stop_block) {
-		path = ext4_find_extent(inode, start, &path, 0);
+	while (start < stop) {
+		path = ext4_find_extent(inode, *iterator, &path, 0);
 		if (IS_ERR(path))
 			return PTR_ERR(path);
 		depth = path->p_depth;
 		extent = path[depth].p_ext;
 		if (!extent) {
 			EXT4_ERROR_INODE(inode, "unexpected hole at %lu",
-					 (unsigned long) start);
-			return -EIO;
+					 (unsigned long) *iterator);
+			return -EFSCORRUPTED;
 		}
-		if (start > le32_to_cpu(extent->ee_block)) {
+		if (SHIFT == SHIFT_LEFT && *iterator >
+		    le32_to_cpu(extent->ee_block)) {
 			/* Hole, move to the next extent */
 			if (extent < EXT_LAST_EXTENT(path[depth].p_hdr)) {
 				path[depth].p_ext++;
 			} else {
-				start = ext4_ext_next_allocated_block(path);
+				*iterator = ext4_ext_next_allocated_block(path);
 				continue;
 			}
 		}
+
+		if (SHIFT == SHIFT_LEFT) {
+			extent = EXT_LAST_EXTENT(path[depth].p_hdr);
+			*iterator = le32_to_cpu(extent->ee_block) +
+					ext4_ext_get_actual_len(extent);
+		} else {
+			extent = EXT_FIRST_EXTENT(path[depth].p_hdr);
+			*iterator =  le32_to_cpu(extent->ee_block) > 0 ?
+				le32_to_cpu(extent->ee_block) - 1 : 0;
+			/* Update path extent in case we need to stop */
+			while (le32_to_cpu(extent->ee_block) < start)
+				extent++;
+			path[depth].p_ext = extent;
+		}
 		ret = ext4_ext_shift_path_extents(path, shift, inode,
-				handle, &start);
+				handle, SHIFT);
 		if (ret)
 			break;
 	}
@@ -5485,7 +5555,7 @@ int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len)
 	ext4_discard_preallocations(inode);
 
 	ret = ext4_ext_shift_extents(inode, handle, punch_stop,
-				     punch_stop - punch_start);
+				     punch_stop - punch_start, SHIFT_LEFT);
 	if (ret) {
 		up_write(&EXT4_I(inode)->i_data_sem);
 		goto out_stop;
@@ -5510,6 +5580,174 @@ out_mutex:
 	return ret;
 }
 
+/*
+ * ext4_insert_range:
+ * This function implements the FALLOC_FL_INSERT_RANGE flag of fallocate.
+ * The data blocks starting from @offset to the EOF are shifted by @len
+ * towards right to create a hole in the @inode. Inode size is increased
+ * by len bytes.
+ * Returns 0 on success, error otherwise.
+ */
+int ext4_insert_range(struct inode *inode, loff_t offset, loff_t len)
+{
+	struct super_block *sb = inode->i_sb;
+	handle_t *handle;
+	struct ext4_ext_path *path;
+	struct ext4_extent *extent;
+	ext4_lblk_t offset_lblk, len_lblk, ee_start_lblk = 0;
+	unsigned int credits, ee_len;
+	int ret = 0, depth, split_flag = 0;
+	loff_t ioffset;
+
+	/*
+	 * We need to test this early because xfstests assumes that an
+	 * insert range of (0, 1) will return EOPNOTSUPP if the file
+	 * system does not support insert range.
+	 */
+	if (!ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
+		return -EOPNOTSUPP;
+
+	/* Insert range works only on fs block size aligned offsets. */
+	if (offset & (EXT4_CLUSTER_SIZE(sb) - 1) ||
+			len & (EXT4_CLUSTER_SIZE(sb) - 1))
+		return -EINVAL;
+
+	if (!S_ISREG(inode->i_mode))
+		return -EOPNOTSUPP;
+
+	trace_ext4_insert_range(inode, offset, len);
+
+	offset_lblk = offset >> EXT4_BLOCK_SIZE_BITS(sb);
+	len_lblk = len >> EXT4_BLOCK_SIZE_BITS(sb);
+
+	/* Call ext4_force_commit to flush all data in case of data=journal */
+	if (ext4_should_journal_data(inode)) {
+		ret = ext4_force_commit(inode->i_sb);
+		if (ret)
+			return ret;
+	}
+
+	/*
+	 * Need to round down to align start offset to page size boundary
+	 * for page size > block size.
+	 */
+	ioffset = round_down(offset, PAGE_SIZE);
+
+	/* Write out all dirty pages */
+	ret = filemap_write_and_wait_range(inode->i_mapping, ioffset,
+			LLONG_MAX);
+	if (ret)
+		return ret;
+
+	/* Take mutex lock */
+	mutex_lock(&inode->i_mutex);
+
+	/* Currently just for extent based files */
+	if (!ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) {
+		ret = -EOPNOTSUPP;
+		goto out_mutex;
+	}
+
+	/* Check for wrap through zero */
+	if (inode->i_size + len > inode->i_sb->s_maxbytes) {
+		ret = -EFBIG;
+		goto out_mutex;
+	}
+
+	/* Offset should be less than i_size */
+	if (offset >= i_size_read(inode)) {
+		ret = -EINVAL;
+		goto out_mutex;
+	}
+
+	truncate_pagecache(inode, ioffset);
+
+	/* Wait for existing dio to complete */
+	ext4_inode_block_unlocked_dio(inode);
+	inode_dio_wait(inode);
+
+	credits = ext4_writepage_trans_blocks(inode);
+	handle = ext4_journal_start(inode, EXT4_HT_TRUNCATE, credits);
+	if (IS_ERR(handle)) {
+		ret = PTR_ERR(handle);
+		goto out_dio;
+	}
+
+	/* Expand file to avoid data loss if there is error while shifting */
+	inode->i_size += len;
+	EXT4_I(inode)->i_disksize += len;
+	inode->i_mtime = inode->i_ctime = ext4_current_time(inode);
+	ret = ext4_mark_inode_dirty(handle, inode);
+	if (ret)
+		goto out_stop;
+
+	down_write(&EXT4_I(inode)->i_data_sem);
+	ext4_discard_preallocations(inode);
+
+	path = ext4_find_extent(inode, offset_lblk, NULL, 0);
+	if (IS_ERR(path)) {
+		up_write(&EXT4_I(inode)->i_data_sem);
+		goto out_stop;
+	}
+
+	depth = ext_depth(inode);
+	extent = path[depth].p_ext;
+	if (extent) {
+		ee_start_lblk = le32_to_cpu(extent->ee_block);
+		ee_len = ext4_ext_get_actual_len(extent);
+
+		/*
+		 * If offset_lblk is not the starting block of extent, split
+		 * the extent @offset_lblk
+		 */
+		if ((offset_lblk > ee_start_lblk) &&
+				(offset_lblk < (ee_start_lblk + ee_len))) {
+			if (ext4_ext_is_unwritten(extent))
+				split_flag = EXT4_EXT_MARK_UNWRIT1 |
+					EXT4_EXT_MARK_UNWRIT2;
+			ret = ext4_split_extent_at(handle, inode, &path,
+					offset_lblk, split_flag,
+					EXT4_EX_NOCACHE |
+					EXT4_GET_BLOCKS_PRE_IO |
+					EXT4_GET_BLOCKS_METADATA_NOFAIL);
+		}
+
+		ext4_ext_drop_refs(path);
+		kfree(path);
+		if (ret < 0) {
+			up_write(&EXT4_I(inode)->i_data_sem);
+			goto out_stop;
+		}
+	}
+
+	ret = ext4_es_remove_extent(inode, offset_lblk,
+			EXT_MAX_BLOCKS - offset_lblk);
+	if (ret) {
+		up_write(&EXT4_I(inode)->i_data_sem);
+		goto out_stop;
+	}
+
+	/*
+	 * if offset_lblk lies in a hole which is at start of file, use
+	 * ee_start_lblk to shift extents
+	 */
+	ret = ext4_ext_shift_extents(inode, handle,
+		ee_start_lblk > offset_lblk ? ee_start_lblk : offset_lblk,
+		len_lblk, SHIFT_RIGHT);
+
+	up_write(&EXT4_I(inode)->i_data_sem);
+	if (IS_SYNC(inode))
+		ext4_handle_sync(handle);
+
+out_stop:
+	ext4_journal_stop(handle);
+out_dio:
+	ext4_inode_resume_unlocked_dio(inode);
+out_mutex:
+	mutex_unlock(&inode->i_mutex);
+	return ret;
+}
+
 /**
  * ext4_swap_extents - Swap extents between two inodes
  *
@@ -5542,7 +5780,7 @@ ext4_swap_extents(handle_t *handle, struct inode *inode1,
 	BUG_ON(!rwsem_is_locked(&EXT4_I(inode1)->i_data_sem));
 	BUG_ON(!rwsem_is_locked(&EXT4_I(inode2)->i_data_sem));
 	BUG_ON(!mutex_is_locked(&inode1->i_mutex));
-	BUG_ON(!mutex_is_locked(&inode1->i_mutex));
+	BUG_ON(!mutex_is_locked(&inode2->i_mutex));
 
 	*erp = ext4_es_remove_extent(inode1, lblk1, count);
 	if (unlikely(*erp))
@@ -5558,7 +5796,7 @@ ext4_swap_extents(handle_t *handle, struct inode *inode1,
 		int split = 0;
 
 		path1 = ext4_find_extent(inode1, lblk1, NULL, EXT4_EX_NOCACHE);
-		if (unlikely(IS_ERR(path1))) {
+		if (IS_ERR(path1)) {
 			*erp = PTR_ERR(path1);
 			path1 = NULL;
 		finish:
@@ -5566,7 +5804,7 @@ ext4_swap_extents(handle_t *handle, struct inode *inode1,
 			goto repeat;
 		}
 		path2 = ext4_find_extent(inode2, lblk2, NULL, EXT4_EX_NOCACHE);
-		if (unlikely(IS_ERR(path2))) {
+		if (IS_ERR(path2)) {
 			*erp = PTR_ERR(path2);
 			path2 = NULL;
 			goto finish;