Re: [PATCH 04/10] fs/dax: make it possible to check dev dax support without a VMA

Christian Brauner <[email protected]> Tue, 17 Jun 2025 13:43:36 +0200
Newsgroups gmane.comp.file-systems.ecryptfs.general,gmane.linux.block,gmane.linux.kernel,gmane.comp.freedesktop.xorg.drivers.intel,gmane.comp.video.dri.devel,gmane.linux.file-systems,gmane.linux.kernel.aio.general,gmane.linux.file-systems.union,gmane.linux.kernel.mm,gmane.comp.file-systems.btrfs,gmane.comp.file-systems.ceph.devel,gmane.comp.file-systems.coda.general,gmane.comp.file-systems.ext4,gmane.linux.file-systems.f2fs,gmane.linux.uml.devel,gmane.linux.drivers.mtd,gmane.linux.nfs,gmane.comp.file-systems.nilfs.user,gmane.linux.hardware.karma.devel,gmane.linux.kernel.cifs,gmane.network.samba.internals
Message-ID <20250617-sehgewohnheiten-getagt-47e1ee917d4f@brauner>
On Mon, Jun 16, 2025 at 09:26:54PM +0100, Matthew Wilcox wrote:
> On Mon, Jun 16, 2025 at 08:33:23PM +0100, Lorenzo Stoakes wrote:
> >  fs/ext4/file.c      |  2 +-
> >  fs/xfs/xfs_file.c   |  3 ++-
> 
> Both of these already have the inode from the file ...
> 
> > +static inline bool daxdev_mapping_supported(vm_flags_t vm_flags,
> > +					    struct file *file,
> > +					    struct dax_device *dax_dev)
> >  {
> > -	if (!(vma->vm_flags & VM_SYNC))
> > +	if (!(vm_flags & VM_SYNC))
> >  		return true;
> > -	if (!IS_DAX(file_inode(vma->vm_file)))
> > +	if (!IS_DAX(file_inode(file)))
> >  		return false;
> >  	return dax_synchronous(dax_dev);
> 
> ... and the only thing this function uses from the file is the inode.
> So maybe pass in the inode rather than the file?

Agreed. I've converted this to take const struct inode *.