Commit eefd7f03 authored by Theodore Ts'o's avatar Theodore Ts'o
Browse files

ext4: fix the length returned by fiemap for an unallocated extent 



If the file's blocks have not yet been allocated because of delayed
allocation, the length of the extent returned by fiemap is incorrect.
This commit fixes this bug.

Signed-off-by: default avatar"Theodore Ts'o" <tytso@mit.edu>
parent c9877b20

fs/ext4/extents.c

+8 −1
Original line number Diff line number Diff line
@@ -3244,8 +3244,15 @@ static int ext4_ext_fiemap_cb(struct inode *inode, struct ext4_ext_path *path, 
	 * XXX this might miss a single-block extent at EXT_MAX_BLOCK

	 */

	if (ext4_ext_next_allocated_block(path) == EXT_MAX_BLOCK ||

	    newex->ec_block + newex->ec_len - 1 == EXT_MAX_BLOCK)

	    newex->ec_block + newex->ec_len - 1 == EXT_MAX_BLOCK) {

		loff_t size = i_size_read(inode);

		loff_t bs = EXT4_BLOCK_SIZE(inode->i_sb);



		flags |= FIEMAP_EXTENT_LAST;

		if ((flags & FIEMAP_EXTENT_DELALLOC) &&

		    logical+length > size)

			length = (size - logical + bs - 1) & ~(bs-1);

	}



	error = fiemap_fill_next_extent(fieinfo, logical, physical,

					length, flags);

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