On Wed, Aug 07, 2024 at 12:42:32PM +0100, John Garry wrote: > On 06/08/2024 20:02, Darrick J. Wong wrote: > > On Thu, Aug 01, 2024 at 04:30:50PM +0000, John Garry wrote: > > > From: "Darrick J. Wong" <djwong@xxxxxxxxxx> > > > > > > Add a new inode flag to require that all file data extent mappings must > > > be aligned (both the file offset range and the allocated space itself) > > > to the extent size hint. Having a separate COW extent size hint is no > > > longer allowed. > > > > > > The goal here is to enable sysadmins and users to mandate that all space > > > mappings in a file must have a startoff/blockcount that are aligned to > > > (say) a 2MB alignment and that the startblock/blockcount will follow the > > > same alignment. > > > > > > Allocated space will be aligned to start of the AG, and not necessarily > > > aligned with disk blocks. The upcoming atomic writes feature will rely and > > > forcealign and will also require allocated space will also be aligned to > > > disk blocks. > > > > > > reflink will not be supported for forcealign yet, so disallow a mount under > > > this condition. This is because we have the limitation of pageache > > > writeback not knowing how to writeback an entire allocation unut, so > > > reject a mount with relink. > > > > > > RT vol will not be supported for forcealign yet, so disallow a mount under > > > this condition. It will be possible to support RT vol and forcealign in > > > future. For this, the inode extsize must be a multiple of rtextsize - this > > > is enforced already in xfs_ioctl_setattr_check_extsize() and > > > xfs_inode_validate_extsize(). > > > > > > Signed-off-by: "Darrick J. Wong" <djwong@xxxxxxxxxx> > > > Co-developed-by: John Garry <john.g.garry@xxxxxxxxxx> > > > [jpg: many changes from orig, including forcealign inode verification > > > rework, ioctl setattr rework disallow reflink a forcealign inode, > > > disallow mount for forcealign + reflink or rt] > > > Signed-off-by: John Garry <john.g.garry@xxxxxxxxxx> > > > > This patch looks ready to me but as I'm the original author I cannot add > > a RVB tag. Someone else needs to add that -- frankly, John is the best > > candidate because he grabbed my patch into his tree and actually > > modified it to do what he wants, which means he's the most familiar with > > it. > > I thought my review would be implied since I noted how I appended it, above. > > Anyway, > > Reviewed-by: John Garry <john.g.garry@xxxxxxxxxx> > > I am hoping that Dave and Christoph will give some formal ack/review when > they get a chance. > > BTW, at what stage do we give XFS_SB_FEAT_RO_COMPAT_FORCEALIGN a more proper > value? So far it has the experimental dev value of 1 << 30, below. When you're ready for the release manager to merge it, change the value, resend the entire series for archival purposes, and send a pull request. --D > Thanks! > > > > > > > > diff --git a/fs/xfs/libxfs/xfs_format.h b/fs/xfs/libxfs/xfs_format.h > > > index e1bfee0c3b1a..95f5259c4255 100644 > > > --- a/fs/xfs/libxfs/xfs_format.h > > > +++ b/fs/xfs/libxfs/xfs_format.h > > > @@ -352,6 +352,7 @@ xfs_sb_has_compat_feature( > > > #define XFS_SB_FEAT_RO_COMPAT_RMAPBT (1 << 1) /* reverse map btree */ > > > #define XFS_SB_FEAT_RO_COMPAT_REFLINK (1 << 2) /* reflinked files */ > > > #define XFS_SB_FEAT_RO_COMPAT_INOBTCNT (1 << 3) /* inobt block counts */ > > > +#define XFS_SB_FEAT_RO_COMPAT_FORCEALIGN (1 << 30) /* aligned file data extents */ > > > #define XFS_SB_FEAT_RO_COMPAT_ALL \ > > > (XFS_SB_FEAT_RO_COMPAT_FINOBT | \ > > > XFS_SB_FEAT_RO_COMPAT_RMAPBT | \ >
