v4: - add request_mask argument to generic_fillattr - Drop current_ctime helper and just code functionality into current_time - rework i_ctime accessor functions A few weeks ago, during one of the discussions around i_version, Dave Chinner wrote this: "You've missed the part where I suggested lifting the "nfsd sampled i_version" state into an inode state flag rather than hiding it in the i_version field. At that point, we could optimise away the secondary ctime updates just like you are proposing we do with the i_version updates. Further, we could also use that state it to decide whether we need to use high resolution timestamps when recording ctime updates - if the nfsd has not sampled the ctime/i_version, we don't need high res timestamps to be recorded for ctime...." While I don't think we can practically optimize away ctime updates like we do with i_version, I do like the idea of using this scheme to indicate when we need to use a high-res timestamp. The basic idea here is to use an unused bit in the timespec64.tv_nsec field to act as a flag to indicate that the value was queried since the last time we updated it. If that flag is set when we go to update the timestamp, we'll clear it and grab a fine-grained ktime value for the update. The first couple of patches add the necessary infrastructure, and the last several patches update various filesystems to use it. For now, I'm focusing on widely-used, exportable filesystems, but this scheme is probably suitable for most filesystems in the kernel. Note that this does cause at least one test failure with LTP's statx06 test. I have submitted a patch to fix the issue (by changing how it fetches the "after" timestamp in that test). Jeff Layton (9): fs: pass the request_mask to generic_fillattr fs: add infrastructure for multigrain inode i_m/ctime overlayfs: allow it to handle multigrain timestamps nfsd: ensure we use ctime_peek to grab the inode->i_ctime ksmbd: use ctime_peek to grab the ctime out of the inode tmpfs: add support for multigrain timestamps xfs: switch to multigrain timestamps ext4: convert to multigrain timestamps btrfs: convert to multigrain timestamps fs/9p/vfs_inode.c | 4 +-- fs/9p/vfs_inode_dotl.c | 4 +-- fs/afs/inode.c | 2 +- fs/btrfs/delayed-inode.c | 2 +- fs/btrfs/inode.c | 4 +-- fs/btrfs/super.c | 5 +-- fs/btrfs/tree-log.c | 2 +- fs/ceph/inode.c | 2 +- fs/cifs/inode.c | 2 +- fs/coda/inode.c | 3 +- fs/ecryptfs/inode.c | 5 +-- fs/erofs/inode.c | 2 +- fs/exfat/file.c | 2 +- fs/ext2/inode.c | 2 +- fs/ext4/inode.c | 19 ++++++++-- fs/ext4/super.c | 2 +- fs/f2fs/file.c | 2 +- fs/fat/file.c | 2 +- fs/fuse/dir.c | 2 +- fs/gfs2/inode.c | 2 +- fs/hfsplus/inode.c | 2 +- fs/inode.c | 48 +++++++++++++++++++++---- fs/kernfs/inode.c | 2 +- fs/ksmbd/smb2pdu.c | 28 +++++++-------- fs/ksmbd/vfs.c | 3 +- fs/libfs.c | 4 +-- fs/minix/inode.c | 2 +- fs/nfs/inode.c | 2 +- fs/nfs/namespace.c | 3 +- fs/nfsd/nfsfh.c | 11 ++++-- fs/ntfs3/file.c | 2 +- fs/ocfs2/file.c | 2 +- fs/orangefs/inode.c | 2 +- fs/overlayfs/file.c | 7 ++-- fs/overlayfs/util.c | 2 +- fs/proc/base.c | 4 +-- fs/proc/fd.c | 2 +- fs/proc/generic.c | 2 +- fs/proc/proc_net.c | 2 +- fs/proc/proc_sysctl.c | 2 +- fs/proc/root.c | 3 +- fs/stat.c | 59 ++++++++++++++++++++++++------ fs/sysv/itree.c | 3 +- fs/ubifs/dir.c | 2 +- fs/udf/symlink.c | 2 +- fs/vboxsf/utils.c | 2 +- fs/xfs/libxfs/xfs_inode_buf.c | 2 +- fs/xfs/xfs_inode_item.c | 2 +- fs/xfs/xfs_iops.c | 4 +-- fs/xfs/xfs_super.c | 2 +- include/linux/fs.h | 68 +++++++++++++++++++++++++++++++++-- mm/shmem.c | 4 +-- 52 files changed, 260 insertions(+), 95 deletions(-) -- 2.40.1
