On Fri, Mar 08, 2024 at 01:03:17PM -0500, Sweet Tea Dorminy wrote: > 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 physical extent length information to fiemap, > and extends btrfs to return it. This uses some of the reserved padding > in the fiemap extent structure, so programs unaware of the new field > will be unaffected by its presence. > > This is based on next-20240307. I've tested the btrfs part of this with > the standard btrfs testing matrix locally, and verified that the physical extent > information returned there is correct, but I'm still waiting on more > tests. Please let me know what you think of the general idea! Seems useful! Any chance you'd be willing to pick up this old proposal to report the dev_t through iomap? iirc the iomap wrappers for fiemap can export that pretty easily. https://lore.kernel.org/linux-fsdevel/20190211094306.fjr6gfehcstm7eqq@xxxxxxxxxxxxxxxxxxxxxxxx/ (Not sure what we do for pmem filesystems) --D > Sweet Tea Dorminy (3): > fs: add physical_length field to fiemap extents > fs: update fiemap_fill_next_extent() signature > btrfs: fiemap: return extent physical size > > Documentation/filesystems/fiemap.rst | 29 +++++++++---- > fs/bcachefs/fs.c | 6 ++- > fs/btrfs/extent_io.c | 63 +++++++++++++++++----------- > fs/ext4/extents.c | 1 + > fs/f2fs/data.c | 8 ++-- > fs/f2fs/inline.c | 3 +- > fs/ioctl.c | 8 ++-- > fs/iomap/fiemap.c | 2 +- > fs/nilfs2/inode.c | 8 ++-- > fs/ntfs3/frecord.c | 6 ++- > fs/ocfs2/extent_map.c | 4 +- > fs/smb/client/smb2ops.c | 1 + > include/linux/fiemap.h | 2 +- > include/uapi/linux/fiemap.h | 24 +++++++---- > 14 files changed, 108 insertions(+), 57 deletions(-) > > > base-commit: 1843e16d2df9d98427ef8045589571749d627cf7 > -- > 2.44.0 > >
