Linux Virtualization - Apr 2019 - [PATCH v4 5/5] xfs: disable map_sync for async flush

On Thu, Apr 04, 2019 at 02:12:30AM -0400, Pankaj Gupta
wrote:
> > All this ad hoc IS_DAX conditional logic is getting pretty nasty.
> > 
> > xfs_file_mmap(
> > ....
> > {
> > 	struct inode	*inode = file_inode(filp);
> > 
> > 	if (vma->vm_flags & VM_SYNC) {
> > 		if (!IS_DAX(inode))
> > 			return -EOPNOTSUPP;
> > 		if (!dax_synchronous(xfs_find_daxdev_for_inode(inode))
> > 			return -EOPNOTSUPP;
> > 	}
> > 
> > 	file_accessed(filp);
> > 	vma->vm_ops = &xfs_file_vm_ops;
> > 	if (IS_DAX(inode))
> > 		vma->vm_flags |= VM_HUGEPAGE;
> > 	return 0;
> > }
> 
> Sure, this is better.
> > Even better, factor out all the "MAP_SYNC supported" checks
into a
> > helper so that the filesystem code just doesn't have to care about
> > the details of checking for DAX+MAP_SYNC support....
> 
> o.k. Will add one common helper function for both ext4 & xfs
filesystems.
Note this pending patch for Goldwyn Rodrigues' patchset for btrfs:

https://lore.kernel.org/linux-btrfs/20190328102418.5466-1-kilobyte at
angband.pl/

We might want to coordinate.


Meow!
-- 
???????
??????? Did ya know that typing "test -j8" instead of "ctest
-j8"
??????? will make your testsuite pass much faster, and fix bugs?
???????

> 
> On Thu, Apr 04, 2019 at 02:12:30AM -0400, Pankaj Gupta wrote:
> > > All this ad hoc IS_DAX conditional logic is getting pretty nasty.
> > > 
> > > xfs_file_mmap(
> > > ....
> > > {
> > > 	struct inode	*inode = file_inode(filp);
> > > 
> > > 	if (vma->vm_flags & VM_SYNC) {
> > > 		if (!IS_DAX(inode))
> > > 			return -EOPNOTSUPP;
> > > 		if (!dax_synchronous(xfs_find_daxdev_for_inode(inode))
> > > 			return -EOPNOTSUPP;
> > > 	}
> > > 
> > > 	file_accessed(filp);
> > > 	vma->vm_ops = &xfs_file_vm_ops;
> > > 	if (IS_DAX(inode))
> > > 		vma->vm_flags |= VM_HUGEPAGE;
> > > 	return 0;
> > > }
> > 
> > Sure, this is better.
> 
> > > Even better, factor out all the "MAP_SYNC supported"
checks into a
> > > helper so that the filesystem code just doesn't have to care
about
> > > the details of checking for DAX+MAP_SYNC support....
> > 
> > o.k. Will add one common helper function for both ext4 & xfs
filesystems.
> 
> Note this pending patch for Goldwyn Rodrigues' patchset for btrfs:
> 
> https://lore.kernel.org/linux-btrfs/20190328102418.5466-1-kilobyte at
angband.pl/
> 
> We might want to coordinate.
Sure. Good to know.

Thanks for the pointer. Will have a look.

Best regards,
Pankaj 
> 
> 
> Meow!
> --
> ???????
> ??????? Did ya know that typing "test -j8" instead of "ctest
-j8"
> ??????? will make your testsuite pass much faster, and fix bugs?
> ???????
>