[PATCH] scsi: cxlflash: Change return type for fault handler

[PATCH] scsi: cxlflash: Change return type for fault handler

[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.

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

Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
---
 drivers/scsi/cxlflash/superpipe.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/scsi/cxlflash/superpipe.c b/drivers/scsi/cxlflash/superpipe.c
index 2fe79df..a4e4c50 100644
--- a/drivers/scsi/cxlflash/superpipe.c
+++ b/drivers/scsi/cxlflash/superpipe.c
@@ -1087,7 +1087,7 @@ static struct page *get_err_page(struct cxlflash_cfg *cfg)
  *
  * Return: 0 on success, VM_FAULT_SIGBUS on failure
  */
-static int cxlflash_mmap_fault(struct vm_fault *vmf)
+static vm_fault_t cxlflash_mmap_fault(struct vm_fault *vmf)
 {
 	struct vm_area_struct *vma = vmf->vma;
 	struct file *file = vma->vm_file;
@@ -1098,7 +1098,7 @@ static int cxlflash_mmap_fault(struct vm_fault *vmf)
 	struct ctx_info *ctxi = NULL;
 	struct page *err_page = NULL;
 	enum ctx_ctrl ctrl = CTX_CTRL_ERR_FALLBACK | CTX_CTRL_FILE;
-	int rc = 0;
+	vm_fault_t rc = 0;
 	int ctxid;
 
 	ctxid = cfg->ops->process_element(ctx);
@@ -1138,7 +1138,7 @@ static int cxlflash_mmap_fault(struct vm_fault *vmf)
 out:
 	if (likely(ctxi))
 		put_context(ctxi);
-	dev_dbg(dev, "%s: returning rc=%d\n", __func__, rc);
+	dev_dbg(dev, "%s: returning rc=%x\n", __func__, rc);
 	return rc;
 
 err:
-- 
1.9.1

Re: [PATCH] scsi: cxlflash: Change return type for fault handler

[Matthew R. Ochs]

On Tue, Jun 12, 2018 at 01:12:04AM +0530, Souptick Joarder 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.
> 
> Ref-> commit 1c8f422059ae ("mm: change return type to vm_fault_t")
> 
> Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>

This looks fine to me.

FYI that there is another handler for this driver in a series
destined for 4.18 and currently in next/master.

Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>

Re: [PATCH] scsi: cxlflash: Change return type for fault handler

[Souptick Joarder]

On Thu, Jun 14, 2018 at 4:53 AM, Matthew R. Ochs
<mrochs@linux.vnet.ibm.com> wrote:
> On Tue, Jun 12, 2018 at 01:12:04AM +0530, Souptick Joarder 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.
>>
>> Ref-> commit 1c8f422059ae ("mm: change return type to vm_fault_t")
>>
>> Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
>
> This looks fine to me.
>
> FYI that there is another handler for this driver in a series
> destined for 4.18 and currently in next/master.
>
> Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
>

Matthew, is this patch queued for 4.19 ?

Re: [PATCH] scsi: cxlflash: Change return type for fault handler

[Uma Krishnan]

> On Jun 19, 2018, at 12:10 AM, Souptick Joarder <jrdr.linux@gmail.com> wrote:
> 
> On Thu, Jun 14, 2018 at 4:53 AM, Matthew R. Ochs
> <mrochs@linux.vnet.ibm.com> wrote:
>> On Tue, Jun 12, 2018 at 01:12:04AM +0530, Souptick Joarder 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.
>>> 
>>> Ref-> commit 1c8f422059ae ("mm: change return type to vm_fault_t")
>>> 
>>> Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
>> 
>> This looks fine to me.
>> 
>> FYI that there is another handler for this driver in a series
>> destined for 4.18 and currently in next/master.
>> 
>> Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
>> 
> 
> Matthew, is this patch queued for 4.19 ?
> 
Below is the commit that added fault handler in ocxl. It is in 4.18 rc1 (upstream/master tree)

commit 93b8f8df552c5a30bfddb75a632f1b2a436c2cae
    scsi: cxlflash: Support adapter context mmap and release

Re: [PATCH] scsi: cxlflash: Change return type for fault handler

[Souptick Joarder]

On Tue, Jun 19, 2018 at 7:41 PM, Uma Krishnan
<ukrishn@linux.vnet.ibm.com> wrote:
>
>
>> On Jun 19, 2018, at 12:10 AM, Souptick Joarder <jrdr.linux@gmail.com> wrote:
>>
>> On Thu, Jun 14, 2018 at 4:53 AM, Matthew R. Ochs
>> <mrochs@linux.vnet.ibm.com> wrote:
>>> On Tue, Jun 12, 2018 at 01:12:04AM +0530, Souptick Joarder 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.
>>>>
>>>> Ref-> commit 1c8f422059ae ("mm: change return type to vm_fault_t")
>>>>
>>>> Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
>>>
>>> This looks fine to me.
>>>
>>> FYI that there is another handler for this driver in a series
>>> destined for 4.18 and currently in next/master.
>>>
>>> Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
>>>
>>
>> Matthew, is this patch queued for 4.19 ?
>>
> Below is the commit that added fault handler in ocxl. It is in 4.18 rc1 (upstream/master tree)
>
> commit 93b8f8df552c5a30bfddb75a632f1b2a436c2cae
>     scsi: cxlflash: Support adapter context mmap and release


No, that's a different patch with commit
93b8f8df552c5a30bfddb75a632f1b2a436c2cae.
Not the patch under discussion in this mail thread :)

Anyway the other patch with commit 93b8f8df552c5a30b also has to be modified
to use new return type vm_fault_t for fault handler ocxlflash_mmap_fault().

Shall I modify and submit the same ?

Re: [PATCH] scsi: cxlflash: Change return type for fault handler

[Matthew R. Ochs]

On Tue, Jun 19, 2018 at 11:11:35PM +0530, Souptick Joarder wrote:
> On Tue, Jun 19, 2018 at 7:41 PM, Uma Krishnan
> <ukrishn@linux.vnet.ibm.com> wrote:
> >
> >
> >> On Jun 19, 2018, at 12:10 AM, Souptick Joarder <jrdr.linux@gmail.com> wrote:
> >>
> >> On Thu, Jun 14, 2018 at 4:53 AM, Matthew R. Ochs
> >> <mrochs@linux.vnet.ibm.com> wrote:
> >>> On Tue, Jun 12, 2018 at 01:12:04AM +0530, Souptick Joarder 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.
> >>>>
> >>>> Ref-> commit 1c8f422059ae ("mm: change return type to vm_fault_t")
> >>>>
> >>>> Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
> >>>
> >>> This looks fine to me.
> >>>
> >>> FYI that there is another handler for this driver in a series
> >>> destined for 4.18 and currently in next/master.
> >>>
> >>> Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
> >>>
> >>
> >> Matthew, is this patch queued for 4.19 ?
> >>
> > Below is the commit that added fault handler in ocxl. It is in 4.18 rc1 (upstream/master tree)
> >
> > commit 93b8f8df552c5a30bfddb75a632f1b2a436c2cae
> >     scsi: cxlflash: Support adapter context mmap and release
> 
> 
> No, that's a different patch with commit
> 93b8f8df552c5a30bfddb75a632f1b2a436c2cae.
> Not the patch under discussion in this mail thread :)
> 
> Anyway the other patch with commit 93b8f8df552c5a30b also has to be modified
> to use new return type vm_fault_t for fault handler ocxlflash_mmap_fault().
> 
> Shall I modify and submit the same ?
> 

Since this has not yet been queued for 4.19, please submit a v2 with the
modifications to also update the return type for ocxlflash_mmap_fault().


-matt

Re: [PATCH] scsi: cxlflash: Change return type for fault handler

[Martin K. Petersen]

Matthew,

> Since this has not yet been queued for 4.19, please submit a v2 with
> the modifications to also update the return type for
> ocxlflash_mmap_fault().

Yes, please. I have been waiting for an amended patch.

-- 
Martin K. Petersen	Oracle Linux Engineering