ext4: make ext4_ind_map_blocks work with fiemap (b2c57642) · Commits · 戴 / test

For indirect block mapping if the i_block > max supported block in inode then ext4_ind_map_blocks() returns a -EIO error. But in case of fiemap this could be a valid query to ->iomap_begin call. So check if the offset >= s_bitmap_maxbytes in ext4_iomap_begin_report(), then simply skip calling ext4_map_blocks(). Signed-off-by:

Ritesh Harjani <riteshh@linux.ibm.com> Reviewed-by:

Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/87fa0ddc5967fa707656212a3b66a7233425325c.1582880246.git.riteshh@linux.ibm.com Signed-off-by:

Theodore Ts'o <tytso@mit.edu>

fs/ext4/inode.c

+16 −0

Original line number	Diff line number	Diff line
		@@ -3546,12 +3546,28 @@ static int ext4_iomap_begin_report(struct inode *inode, loff_t offset,
		map.m_len = min_t(loff_t, (offset + length - 1) >> blkbits,
		EXT4_MAX_LOGICAL_BLOCK) - map.m_lblk + 1;

		/*
		* Fiemap callers may call for offset beyond s_bitmap_maxbytes.
		* So handle it here itself instead of querying ext4_map_blocks().
		* Since ext4_map_blocks() will warn about it and will return
		* -EIO error.
		*/
		if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) {
		struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);

		if (offset >= sbi->s_bitmap_maxbytes) {
		map.m_flags = 0;
		goto set_iomap;
		}
		}

		ret = ext4_map_blocks(NULL, inode, &map, 0);
		if (ret < 0)
		return ret;
		if (ret == 0)
		delalloc = ext4_iomap_is_delalloc(inode, &map);

		set_iomap:
		ext4_set_iomap(inode, iomap, &map, offset, length);
		if (delalloc && iomap->type == IOMAP_HOLE)
		iomap->type = IOMAP_DELALLOC;

Admin message