On Wed, Apr 30, 2025 at 02:59:06PM +0200, Christoph Hellwig wrote: > On Tue, Apr 29, 2025 at 07:44:46AM -0700, Darrick J. Wong wrote: > > > So this can't be merged into xfs_setsize_buftarg as suggeted last round > > > instead of needing yet another per-device call into the buftarg code? > > > > Oh, heh, I forgot that xfs_setsize_buftarg is called a second time by > > xfs_setup_devices at the end of fill_super. > > That's actually the real call. The first is just a dummy to have > bt_meta_sectorsize/bt_meta_sectormask initialized because if we didn't > do that some assert in the block layer triggered. We should probably > remove that call and open code the two assignments.. > > > I don't like the idea of merging the hw atomic write detection into > > xfs_setsize_buftarg itself because (a) it gets called for the data > > device before we've read the fs blocksize so the validation is > > meaningless and (b) that makes xfs_setsize_buftarg's purpose less > > cohesive. > > As explained last round this came up I'd of course rename it if > we did that. But I can do that later. <nod> Would you be willing to review this patch as it is now and either you or me can just tack a new cleanup patch on the end? I tried writing a patch to clean this up, but ran into questions: At first I thought that the xfs_setsize_buftarg call in xfs_alloc_buftarg could be replaced by open-coding the bt_meta_sector* assignment, checking that bdev_validate_blocksize is ok, and dropping the sync_blockdev. Once we get to xfs_setup_devices, we can call xfs_setsize_buftarg on the three buftargs, and xfs_setsize_buftarg will configure the atomic writes geometry. But then as I was reading the patch, it occurred to me that at least for the data device, we actually /do/ want that sync_blockdev call so that any dirty pagecache for the superblock actually get written to disk. Maybe that can go at the end of xfs_open_devices? But would it be preferable to sync all the devices prior to trying to read the primary sb? I don't think there's a need, but maybe someone else has a different viewpoint? --D
