On Oct 24, 2008 19:09 +0900, Akira Fujita wrote: > The EXT4_IOC_FIEMAP_INO is used to get extents information of > inode which set to ioctl. > The defragger uses this ioctl to check the fragment condition > and to get extents information in the specified block group. Instead of having a separate IOC number for each such ioctl, instead we implemented EXT4_IOC_WRAPPER, which is an root-specific ioctl that passes in an inode number and a second IOC number so that arbitrary file ioctls can be run on any inode by root. This was mentioned last time these patches were posted, but there was no reply from you. Christoph suggested a more generic VFS open-by-inum, which isn't impossible to do but would cause a lot of controversy I think, while the EXT4_IOC_WRAPPER is at least contained within ext4, but is more generically useful than EXT4_IOC_FIEMAP_INO. Cheers, Andreas -- Andreas Dilger Sr. Staff Engineer, Lustre Group Sun Microsystems of Canada, Inc. -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
