[PATCH] include: dax: new-return-type-vm_fault_t

[PATCH] include: dax: new-return-type-vm_fault_t

[Souptick Joarder]

Use new return type vm_fault_t for fault handler. For now,
this is just documenting that the function returns a VM_FAULT
value rather than an errno. Once all instances are converted,
vm_fault_t will become a distinct type.

commit 1c8f422059ae ("mm: change return type to vm_fault_t")

Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
---
 include/linux/dax.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/dax.h b/include/linux/dax.h
index 7fddea8..11852d2 100644
--- a/include/linux/dax.h
+++ b/include/linux/dax.h
@@ -122,7 +122,7 @@ size_t dax_copy_from_iter(struct dax_device *dax_dev, pgoff_t pgoff, void *addr,
 
 ssize_t dax_iomap_rw(struct kiocb *iocb, struct iov_iter *iter,
 		const struct iomap_ops *ops);
-int dax_iomap_fault(struct vm_fault *vmf, enum page_entry_size pe_size,
+vm_fault_t dax_iomap_fault(struct vm_fault *vmf, enum page_entry_size pe_size,
 		    pfn_t *pfnp, int *errp, const struct iomap_ops *ops);
 vm_fault_t dax_finish_sync_fault(struct vm_fault *vmf,
 		enum page_entry_size pe_size, pfn_t pfn);
-- 
1.9.1

Re: [PATCH] include: dax: new-return-type-vm_fault_t

[Souptick Joarder]

On Wed, Jun 20, 2018 at 10:50 PM, Souptick Joarder <jrdr.linux@gmail.com> wrote:
> Use new return type vm_fault_t for fault handler. For now,
> this is just documenting that the function returns a VM_FAULT
> value rather than an errno. Once all instances are converted,
> vm_fault_t will become a distinct type.
>
> commit 1c8f422059ae ("mm: change return type to vm_fault_t")
>
> Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
> ---
>  include/linux/dax.h | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/include/linux/dax.h b/include/linux/dax.h
> index 7fddea8..11852d2 100644
> --- a/include/linux/dax.h
> +++ b/include/linux/dax.h
> @@ -122,7 +122,7 @@ size_t dax_copy_from_iter(struct dax_device *dax_dev, pgoff_t pgoff, void *addr,
>
>  ssize_t dax_iomap_rw(struct kiocb *iocb, struct iov_iter *iter,
>                 const struct iomap_ops *ops);
> -int dax_iomap_fault(struct vm_fault *vmf, enum page_entry_size pe_size,
> +vm_fault_t dax_iomap_fault(struct vm_fault *vmf, enum page_entry_size pe_size,
>                     pfn_t *pfnp, int *errp, const struct iomap_ops *ops);
>  vm_fault_t dax_finish_sync_fault(struct vm_fault *vmf,
>                 enum page_entry_size pe_size, pfn_t pfn);
> --
> 1.9.1
>

Matthew/ Andrew,

As part of
commit ab77dab46210 ("fs/dax.c: use new return type vm_fault_t")
I missed this change which leads to compilation error.
Sorry about it.

This patch need to be in 4.18-rc-2/x on priority.

Re: [PATCH] include: dax: new-return-type-vm_fault_t

[Matthew Wilcox]

On Wed, Jun 20, 2018 at 10:51:49PM +0530, Souptick Joarder wrote:
> On Wed, Jun 20, 2018 at 10:50 PM, Souptick Joarder <jrdr.linux@gmail.com> wrote:
> > Use new return type vm_fault_t for fault handler. For now,
> > this is just documenting that the function returns a VM_FAULT
> > value rather than an errno. Once all instances are converted,
> > vm_fault_t will become a distinct type.

> As part of
> commit ab77dab46210 ("fs/dax.c: use new return type vm_fault_t")
> I missed this change which leads to compilation error.
> Sorry about it.
> 
> This patch need to be in 4.18-rc-2/x on priority.

It only leads to a compilation error for you; the rest of us are still
using typedef int vm_fault_t, so it's not a mismatch.  It'd be nice to get
this fixed, but it's not a priority.

Sorry I didn't spot this during my review.