For many years, various btrfs users have written programs to discover the actual disk space used by files, using root-only interfaces. However, this information is a great fit for fiemap: it is inherently tied to extent information, all filesystems can use it, and the capabilities required for FIEMAP make sense for this additional information also. Hence, this patchset adds various additional information to fiemap, and extends filesystems (but not iomap) to return it. This uses some of the reserved padding in the fiemap extent structure, so programs unaware of the changes will be unaffected. This is based on next-20240403. I've tested the btrfs part of this with the standard btrfs testing matrix locally and manually, and done minimal testing of the non-btrfs parts. I'm unsure whether btrfs should be returning the entire physical extent referenced by a particular logical range, or just the part of the physical extent referenced by that range. The v2 thread has a discussion of this. Changelog: v3: - Adapted all the direct users of fiemap, except iomap, to emit the new fiemap information, as far as I understand the other filesystems. v2: - Adopted PHYS_LEN flag and COMPRESSED flag from the previous version, as per Andreas Dilger' comment. https://patchwork.ozlabs.org/project/linux-ext4/patch/4f8d5dc5b51a43efaf16c39398c23a6276e40a30.1386778303.git.dsterba@xxxxxxx/ - https://lore.kernel.org/linux-fsdevel/cover.1711588701.git.sweettea-kernel@xxxxxxxxxx/T/#t v1: https://lore.kernel.org/linux-fsdevel/20240315030334.GQ6184@frogsfrogsfrogs/T/#t Sweet Tea Dorminy (13): fs: fiemap: add physical_length field to extents fs: fiemap: update fiemap_fill_next_extent() signature fs: fiemap: add new COMPRESSED extent state btrfs: fiemap: emit new COMPRESSED state. btrfs: fiemap: return extent physical size nilfs2: fiemap: return correct extent physical length ext4: fiemap: return correct extent physical length f2fs: fiemap: add physical length to trace_f2fs_fiemap f2fs: fiemap: return correct extent physical length ocfs2: fiemap: return correct extent physical length bcachefs: fiemap: return correct extent physical length f2fs: fiemap: emit new COMPRESSED state bcachefs: fiemap: emit new COMPRESSED state Documentation/filesystems/fiemap.rst | 35 ++++++++++---- fs/bcachefs/fs.c | 17 +++++-- fs/btrfs/extent_io.c | 72 ++++++++++++++++++---------- fs/ext4/extents.c | 3 +- fs/f2fs/data.c | 36 +++++++++----- fs/f2fs/inline.c | 7 +-- fs/ioctl.c | 11 +++-- fs/iomap/fiemap.c | 2 +- fs/nilfs2/inode.c | 18 ++++--- fs/ntfs3/frecord.c | 7 +-- fs/ocfs2/extent_map.c | 10 ++-- fs/smb/client/smb2ops.c | 1 + include/linux/fiemap.h | 2 +- include/trace/events/f2fs.h | 10 ++-- include/uapi/linux/fiemap.h | 34 ++++++++++--- 15 files changed, 178 insertions(+), 87 deletions(-) base-commit: 75e31f66adc4c8d049e8aac1f079c1639294cd65 -- 2.43.0