diff mbox series

[1/7] fsdax: Output address in dax_iomap_pfn() and rename it

Message ID 20210207170924.2933035-2-ruansy.fnst@cn.fujitsu.com (mailing list archive)
State New, archived
Headers show
Series fsdax,xfs: Add reflink&dedupe support for fsdax | expand

Commit Message

Ruan Shiyang Feb. 7, 2021, 5:09 p.m. UTC 
Add address output in dax_iomap_pfn() in order to perform a memcpy() in
CoW case.  Since this function both output address and pfn, rename it to
dax_iomap_direct_access().

Signed-off-by: Shiyang Ruan <ruansy.fnst@cn.fujitsu.com>
---
 fs/dax.c | 20 +++++++++++++++-----
 1 file changed, 15 insertions(+), 5 deletions(-)

Comments

Christoph Hellwig Feb. 8, 2021, 3:11 p.m. UTC | #1 
Looks good,

Reviewed-by: Christoph Hellwig <hch@lst.de>
Xiaoguang Wang Feb. 22, 2021, 7:44 a.m. UTC | #2 
hi,

> Add address output in dax_iomap_pfn() in order to perform a memcpy() in
> CoW case.  Since this function both output address and pfn, rename it to
> dax_iomap_direct_access().
> 
> Signed-off-by: Shiyang Ruan <ruansy.fnst@cn.fujitsu.com>
> ---
>   fs/dax.c | 20 +++++++++++++++-----
>   1 file changed, 15 insertions(+), 5 deletions(-)
> 
> diff --git a/fs/dax.c b/fs/dax.c
> index 5b47834f2e1b..b012b2db7ba2 100644
> --- a/fs/dax.c
> +++ b/fs/dax.c
> @@ -998,8 +998,8 @@ static sector_t dax_iomap_sector(struct iomap *iomap, loff_t pos)
>   	return (iomap->addr + (pos & PAGE_MASK) - iomap->offset) >> 9;
>   }
>   
> -static int dax_iomap_pfn(struct iomap *iomap, loff_t pos, size_t size,
> -			 pfn_t *pfnp)
> +static int dax_iomap_direct_access(struct iomap *iomap, loff_t pos, size_t size,
> +		void **kaddr, pfn_t *pfnp)
>   {
>   	const sector_t sector = dax_iomap_sector(iomap, pos);
>   	pgoff_t pgoff;
> @@ -1011,11 +1011,13 @@ static int dax_iomap_pfn(struct iomap *iomap, loff_t pos, size_t size,
>   		return rc;
>   	id = dax_read_lock();
>   	length = dax_direct_access(iomap->dax_dev, pgoff, PHYS_PFN(size),
> -				   NULL, pfnp);
> +				   kaddr, pfnp);
>   	if (length < 0) {
>   		rc = length;
>   		goto out;
>   	}
> +	if (!pfnp)
Should this be "if (!*pfnp)"?

Regards,
Xiaoguang Wang
> +		goto out_check_addr;
>   	rc = -EINVAL;
>   	if (PFN_PHYS(length) < size)
>   		goto out;
> @@ -1025,6 +1027,12 @@ static int dax_iomap_pfn(struct iomap *iomap, loff_t pos, size_t size,
>   	if (length > 1 && !pfn_t_devmap(*pfnp))
>   		goto out;
>   	rc = 0;
> +
> +out_check_addr:
> +	if (!kaddr)
> +		goto out;
> +	if (!*kaddr)
> +		rc = -EFAULT;
>   out:
>   	dax_read_unlock(id);
>   	return rc;
> @@ -1348,7 +1356,8 @@ static vm_fault_t dax_iomap_pte_fault(struct vm_fault *vmf, pfn_t *pfnp,
>   			count_memcg_event_mm(vma->vm_mm, PGMAJFAULT);
>   			major = VM_FAULT_MAJOR;
>   		}
> -		error = dax_iomap_pfn(&iomap, pos, PAGE_SIZE, &pfn);
> +		error = dax_iomap_direct_access(&iomap, pos, PAGE_SIZE,
> +						NULL, &pfn);
>   		if (error < 0)
>   			goto error_finish_iomap;
>   
> @@ -1566,7 +1575,8 @@ static vm_fault_t dax_iomap_pmd_fault(struct vm_fault *vmf, pfn_t *pfnp,
>   
>   	switch (iomap.type) {
>   	case IOMAP_MAPPED:
> -		error = dax_iomap_pfn(&iomap, pos, PMD_SIZE, &pfn);
> +		error = dax_iomap_direct_access(&iomap, pos, PMD_SIZE,
> +						NULL, &pfn);
>   		if (error < 0)
>   			goto finish_iomap;
>   
>
Shiyang Ruan Feb. 23, 2021, 1:32 a.m. UTC | #3 
> hi,
> 
> > Add address output in dax_iomap_pfn() in order to perform a memcpy() in
> > CoW case.  Since this function both output address and pfn, rename it to
> > dax_iomap_direct_access().
> >
> > Signed-off-by: Shiyang Ruan <ruansy.fnst@cn.fujitsu.com>
> > ---
> >   fs/dax.c | 20 +++++++++++++++-----
> >   1 file changed, 15 insertions(+), 5 deletions(-)
> >
> > diff --git a/fs/dax.c b/fs/dax.c
> > index 5b47834f2e1b..b012b2db7ba2 100644
> > --- a/fs/dax.c
> > +++ b/fs/dax.c
> > @@ -998,8 +998,8 @@ static sector_t dax_iomap_sector(struct iomap *iomap, loff_t pos)
> >        return (iomap->addr + (pos & PAGE_MASK) - iomap->offset) >> 9;
> >   }
> >  
> > -static int dax_iomap_pfn(struct iomap *iomap, loff_t pos, size_t size,
> > -                      pfn_t *pfnp)
> > +static int dax_iomap_direct_access(struct iomap *iomap, loff_t pos, size_t size,
> > +             void **kaddr, pfn_t *pfnp)
> >   {
> >        const sector_t sector = dax_iomap_sector(iomap, pos);
> >        pgoff_t pgoff;
> > @@ -1011,11 +1011,13 @@ static int dax_iomap_pfn(struct iomap *iomap, loff_t pos, size_t size,
> >                return rc;
> >        id = dax_read_lock();
> >        length = dax_direct_access(iomap->dax_dev, pgoff, PHYS_PFN(size),
> > -                                NULL, pfnp);
> > +                                kaddr, pfnp);
> >        if (length < 0) {
> >                rc = length;
> >                goto out;
> >        }
> > +     if (!pfnp)
> Should this be "if (!*pfnp)"?

pfnp may be NULL if we only need a kaddr output.
  `dax_iomap_direct_access(iomap, pos, size, &kaddr, NULL);`

So, it's a NULL pointer check here.


--
Thanks,
Ruan Shiyang.

> 
> Regards,
> Xiaoguang Wang
> > +             goto out_check_addr;
> >        rc = -EINVAL;
> >        if (PFN_PHYS(length) < size)
> >                goto out;
> > @@ -1025,6 +1027,12 @@ static int dax_iomap_pfn(struct iomap *iomap, loff_t pos, size_t size,
> >        if (length > 1 && !pfn_t_devmap(*pfnp))
> >                goto out;
> >        rc = 0;
> > +
> > +out_check_addr:
> > +     if (!kaddr)
> > +             goto out;
> > +     if (!*kaddr)
> > +             rc = -EFAULT;
> >   out:
> >        dax_read_unlock(id);
> >        return rc;
>
diff mbox series

Patch

diff --git a/fs/dax.c b/fs/dax.c
index 5b47834f2e1b..b012b2db7ba2 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -998,8 +998,8 @@  static sector_t dax_iomap_sector(struct iomap *iomap, loff_t pos)
 	return (iomap->addr + (pos & PAGE_MASK) - iomap->offset) >> 9;
 }
 
-static int dax_iomap_pfn(struct iomap *iomap, loff_t pos, size_t size,
-			 pfn_t *pfnp)
+static int dax_iomap_direct_access(struct iomap *iomap, loff_t pos, size_t size,
+		void **kaddr, pfn_t *pfnp)
 {
 	const sector_t sector = dax_iomap_sector(iomap, pos);
 	pgoff_t pgoff;
@@ -1011,11 +1011,13 @@  static int dax_iomap_pfn(struct iomap *iomap, loff_t pos, size_t size,
 		return rc;
 	id = dax_read_lock();
 	length = dax_direct_access(iomap->dax_dev, pgoff, PHYS_PFN(size),
-				   NULL, pfnp);
+				   kaddr, pfnp);
 	if (length < 0) {
 		rc = length;
 		goto out;
 	}
+	if (!pfnp)
+		goto out_check_addr;
 	rc = -EINVAL;
 	if (PFN_PHYS(length) < size)
 		goto out;
@@ -1025,6 +1027,12 @@  static int dax_iomap_pfn(struct iomap *iomap, loff_t pos, size_t size,
 	if (length > 1 && !pfn_t_devmap(*pfnp))
 		goto out;
 	rc = 0;
+
+out_check_addr:
+	if (!kaddr)
+		goto out;
+	if (!*kaddr)
+		rc = -EFAULT;
 out:
 	dax_read_unlock(id);
 	return rc;
@@ -1348,7 +1356,8 @@  static vm_fault_t dax_iomap_pte_fault(struct vm_fault *vmf, pfn_t *pfnp,
 			count_memcg_event_mm(vma->vm_mm, PGMAJFAULT);
 			major = VM_FAULT_MAJOR;
 		}
-		error = dax_iomap_pfn(&iomap, pos, PAGE_SIZE, &pfn);
+		error = dax_iomap_direct_access(&iomap, pos, PAGE_SIZE,
+						NULL, &pfn);
 		if (error < 0)
 			goto error_finish_iomap;
 
@@ -1566,7 +1575,8 @@  static vm_fault_t dax_iomap_pmd_fault(struct vm_fault *vmf, pfn_t *pfnp,
 
 	switch (iomap.type) {
 	case IOMAP_MAPPED:
-		error = dax_iomap_pfn(&iomap, pos, PMD_SIZE, &pfn);
+		error = dax_iomap_direct_access(&iomap, pos, PMD_SIZE,
+						NULL, &pfn);
 		if (error < 0)
 			goto finish_iomap;