We've recently seen some interesting behavior with ftruncate() following a fallocate() call on ext4, and would like to know if this is intended or not. The sequence used from user space: fd = open() fallocate(fd, FALLOC_FL_KEEP_SIZE, 8MB) write(fd, buf, 64KB) ftruncate(fd, 64KB) close(fd) Since inode_setattr() only does something if the input size is not the same as inode->i_size, the ftruncate() call above does nothing; no blocks from the fallocate() are freed up. Yes, removing the KEEP_SIZE flag gets the behavior I'm expecting, but KEEP_SIZE is quite convenient in recovering from errors. I would have thought that ftruncate() would alter i_disksize even if this value is different from i_size. Any comments? I looked at other Linux file systems, and none that I saw that support fallocate() have this issue. Thanks, Curt -- 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
