Re: [PATCH 08/18] dax: memcpy page in case of IOMAP_DAX_COW for mmap faults
On Tue 21-05-19 10:46:25, Darrick J. Wong wrote:
> On Mon, Apr 29, 2019 at 12:26:39PM -0500, Goldwyn Rodrigues wrote:
> > From: Goldwyn Rodrigues
> >
> > Change dax_iomap_pfn to return the address as well in order to
> > use it for performing a memcpy in case the type is IOMAP_DAX_COW.
> > We don't handle PMD because btrfs does not support hugepages.
> >
> > Question:
> > The sequence of bdev_dax_pgoff() and dax_direct_access() is
> > used multiple times to calculate address and pfn's. Would it make
> > sense to call it while calculating address as well to reduce code?
> >
> > Signed-off-by: Goldwyn Rodrigues
> > ---
> > fs/dax.c | 19 +++
> > 1 file changed, 15 insertions(+), 4 deletions(-)
> >
> > diff --git a/fs/dax.c b/fs/dax.c
> > index 610bfa861a28..718b1632a39d 100644
> > --- a/fs/dax.c
> > +++ b/fs/dax.c
> > @@ -984,7 +984,7 @@ static sector_t dax_iomap_sector(struct iomap *iomap,
> > loff_t pos)
> > }
> >
> > static int dax_iomap_pfn(struct iomap *iomap, loff_t pos, size_t size,
> > -pfn_t *pfnp)
> > +pfn_t *pfnp, void **addr)
> > {
> > const sector_t sector = dax_iomap_sector(iomap, pos);
> > pgoff_t pgoff;
> > @@ -996,7 +996,7 @@ 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);
> > + addr, pfnp);
> > if (length < 0) {
> > rc = length;
> > goto out;
> > @@ -1286,6 +1286,7 @@ static vm_fault_t dax_iomap_pte_fault(struct vm_fault
> > *vmf, pfn_t *pfnp,
> > XA_STATE(xas, &mapping->i_pages, vmf->pgoff);
> > struct inode *inode = mapping->host;
> > unsigned long vaddr = vmf->address;
> > + void *addr;
> > loff_t pos = (loff_t)vmf->pgoff << PAGE_SHIFT;
> > struct iomap iomap = { 0 };
>
> Ugh, I had forgotten that fs/dax.c open-codes iomap_apply, probably
> because the actor returns vm_fault_t, not bytes copied. I guess that
> makes it a tiny bit more complicated to pass in two (struct iomap *) to
> the iomap_begin function...
Hum, right. We could actually reimplement dax_iomap_{pte|pmd}_fault() using
iomap_apply(). We would just need to propagate error code out of our
'actor' inside the structure pointed to by 'data'. But that's doable.
Honza
--
Jan Kara
SUSE Labs, CR
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Re: [PATCH 08/18] dax: memcpy page in case of IOMAP_DAX_COW for mmap faults
On Wed, May 22, 2019 at 02:11:39PM -0500, Goldwyn Rodrigues wrote:
> On 10:46 21/05, Darrick J. Wong wrote:
> > On Mon, Apr 29, 2019 at 12:26:39PM -0500, Goldwyn Rodrigues wrote:
> > > From: Goldwyn Rodrigues
> > >
> > > Change dax_iomap_pfn to return the address as well in order to
> > > use it for performing a memcpy in case the type is IOMAP_DAX_COW.
> > > We don't handle PMD because btrfs does not support hugepages.
> > >
> > > Question:
> > > The sequence of bdev_dax_pgoff() and dax_direct_access() is
> > > used multiple times to calculate address and pfn's. Would it make
> > > sense to call it while calculating address as well to reduce code?
> > >
> > > Signed-off-by: Goldwyn Rodrigues
> > > ---
> > > fs/dax.c | 19 +++
> > > 1 file changed, 15 insertions(+), 4 deletions(-)
> > >
> > > diff --git a/fs/dax.c b/fs/dax.c
> > > index 610bfa861a28..718b1632a39d 100644
> > > --- a/fs/dax.c
> > > +++ b/fs/dax.c
> > > @@ -984,7 +984,7 @@ static sector_t dax_iomap_sector(struct iomap *iomap,
> > > loff_t pos)
> > > }
> > >
> > > static int dax_iomap_pfn(struct iomap *iomap, loff_t pos, size_t size,
> > > - pfn_t *pfnp)
> > > + pfn_t *pfnp, void **addr)
> > > {
> > > const sector_t sector = dax_iomap_sector(iomap, pos);
> > > pgoff_t pgoff;
> > > @@ -996,7 +996,7 @@ 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);
> > > +addr, pfnp);
> > > if (length < 0) {
> > > rc = length;
> > > goto out;
> > > @@ -1286,6 +1286,7 @@ static vm_fault_t dax_iomap_pte_fault(struct
> > > vm_fault *vmf, pfn_t *pfnp,
> > > XA_STATE(xas, &mapping->i_pages, vmf->pgoff);
> > > struct inode *inode = mapping->host;
> > > unsigned long vaddr = vmf->address;
> > > + void *addr;
> > > loff_t pos = (loff_t)vmf->pgoff << PAGE_SHIFT;
> > > struct iomap iomap = { 0 };
> >
> > Ugh, I had forgotten that fs/dax.c open-codes iomap_apply, probably
> > because the actor returns vm_fault_t, not bytes copied. I guess that
> > makes it a tiny bit more complicated to pass in two (struct iomap *) to
> > the iomap_begin function...
>
> I am not sure I understand this. We do not use iomap_apply() in
> the fault path: dax_iomap_pte_fault(). We just use iomap_begin()
> and iomap_end(). So, why can we not implement your idea of using two
> iomaps?
Oh, sorry, I wasn't trying to say that calling ->iomap_begin made it
*impossible* to implement. I was merely complaining about the increased
maintenance burden that results from open coding -- now there are three
places where we have to change a struct iomap declaration, not one
(iomap_apply) as I had originally thought.
> What does open-coding iomap-apply mean?
Any function that calls (1) ->iomap_begin; (2) performs an action on the
returned iomap; and (3) then calls calling ->iomap_end. That's what
iomap_apply() does.
Really I'm just being maintainer-cranky. Ignore me for now. :)
--D
>
> --
> Goldwyn
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Re: [PATCH 08/18] dax: memcpy page in case of IOMAP_DAX_COW for mmap faults
On 10:46 21/05, Darrick J. Wong wrote:
> On Mon, Apr 29, 2019 at 12:26:39PM -0500, Goldwyn Rodrigues wrote:
> > From: Goldwyn Rodrigues
> >
> > Change dax_iomap_pfn to return the address as well in order to
> > use it for performing a memcpy in case the type is IOMAP_DAX_COW.
> > We don't handle PMD because btrfs does not support hugepages.
> >
> > Question:
> > The sequence of bdev_dax_pgoff() and dax_direct_access() is
> > used multiple times to calculate address and pfn's. Would it make
> > sense to call it while calculating address as well to reduce code?
> >
> > Signed-off-by: Goldwyn Rodrigues
> > ---
> > fs/dax.c | 19 +++
> > 1 file changed, 15 insertions(+), 4 deletions(-)
> >
> > diff --git a/fs/dax.c b/fs/dax.c
> > index 610bfa861a28..718b1632a39d 100644
> > --- a/fs/dax.c
> > +++ b/fs/dax.c
> > @@ -984,7 +984,7 @@ static sector_t dax_iomap_sector(struct iomap *iomap,
> > loff_t pos)
> > }
> >
> > static int dax_iomap_pfn(struct iomap *iomap, loff_t pos, size_t size,
> > -pfn_t *pfnp)
> > +pfn_t *pfnp, void **addr)
> > {
> > const sector_t sector = dax_iomap_sector(iomap, pos);
> > pgoff_t pgoff;
> > @@ -996,7 +996,7 @@ 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);
> > + addr, pfnp);
> > if (length < 0) {
> > rc = length;
> > goto out;
> > @@ -1286,6 +1286,7 @@ static vm_fault_t dax_iomap_pte_fault(struct vm_fault
> > *vmf, pfn_t *pfnp,
> > XA_STATE(xas, &mapping->i_pages, vmf->pgoff);
> > struct inode *inode = mapping->host;
> > unsigned long vaddr = vmf->address;
> > + void *addr;
> > loff_t pos = (loff_t)vmf->pgoff << PAGE_SHIFT;
> > struct iomap iomap = { 0 };
>
> Ugh, I had forgotten that fs/dax.c open-codes iomap_apply, probably
> because the actor returns vm_fault_t, not bytes copied. I guess that
> makes it a tiny bit more complicated to pass in two (struct iomap *) to
> the iomap_begin function...
I am not sure I understand this. We do not use iomap_apply() in
the fault path: dax_iomap_pte_fault(). We just use iomap_begin()
and iomap_end(). So, why can we not implement your idea of using two
iomaps? What does open-coding iomap-apply mean?
--
Goldwyn
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Re: [PATCH 08/18] dax: memcpy page in case of IOMAP_DAX_COW for mmap faults
On Mon, Apr 29, 2019 at 12:26:39PM -0500, Goldwyn Rodrigues wrote:
> From: Goldwyn Rodrigues
>
> Change dax_iomap_pfn to return the address as well in order to
> use it for performing a memcpy in case the type is IOMAP_DAX_COW.
> We don't handle PMD because btrfs does not support hugepages.
>
> Question:
> The sequence of bdev_dax_pgoff() and dax_direct_access() is
> used multiple times to calculate address and pfn's. Would it make
> sense to call it while calculating address as well to reduce code?
>
> Signed-off-by: Goldwyn Rodrigues
> ---
> fs/dax.c | 19 +++
> 1 file changed, 15 insertions(+), 4 deletions(-)
>
> diff --git a/fs/dax.c b/fs/dax.c
> index 610bfa861a28..718b1632a39d 100644
> --- a/fs/dax.c
> +++ b/fs/dax.c
> @@ -984,7 +984,7 @@ static sector_t dax_iomap_sector(struct iomap *iomap,
> loff_t pos)
> }
>
> static int dax_iomap_pfn(struct iomap *iomap, loff_t pos, size_t size,
> - pfn_t *pfnp)
> + pfn_t *pfnp, void **addr)
> {
> const sector_t sector = dax_iomap_sector(iomap, pos);
> pgoff_t pgoff;
> @@ -996,7 +996,7 @@ 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);
> +addr, pfnp);
> if (length < 0) {
> rc = length;
> goto out;
> @@ -1286,6 +1286,7 @@ static vm_fault_t dax_iomap_pte_fault(struct vm_fault
> *vmf, pfn_t *pfnp,
> XA_STATE(xas, &mapping->i_pages, vmf->pgoff);
> struct inode *inode = mapping->host;
> unsigned long vaddr = vmf->address;
> + void *addr;
> loff_t pos = (loff_t)vmf->pgoff << PAGE_SHIFT;
> struct iomap iomap = { 0 };
Ugh, I had forgotten that fs/dax.c open-codes iomap_apply, probably
because the actor returns vm_fault_t, not bytes copied. I guess that
makes it a tiny bit more complicated to pass in two (struct iomap *) to
the iomap_begin function...
> unsigned flags = IOMAP_FAULT;
> @@ -1375,16 +1376,26 @@ static vm_fault_t dax_iomap_pte_fault(struct vm_fault
> *vmf, pfn_t *pfnp,
> sync = dax_fault_is_synchronous(flags, vma, &iomap);
>
> switch (iomap.type) {
> + case IOMAP_DAX_COW:
> case IOMAP_MAPPED:
> if (iomap.flags & IOMAP_F_NEW) {
> count_vm_event(PGMAJFAULT);
> count_memcg_event_mm(vma->vm_mm, PGMAJFAULT);
> major = VM_FAULT_MAJOR;
> }
> - error = dax_iomap_pfn(&iomap, pos, PAGE_SIZE, &pfn);
> + error = dax_iomap_pfn(&iomap, pos, PAGE_SIZE, &pfn, &addr);
> if (error < 0)
> goto error_finish_iomap;
>
> + if (iomap.type == IOMAP_DAX_COW) {
> + if (iomap.inline_data) {
> + error = memcpy_mcsafe(addr, iomap.inline_data,
> + PAGE_SIZE);
> + if (error < 0)
> + goto error_finish_iomap;
> + } else
> + memset(addr, 0, PAGE_SIZE);
This memcpy_mcsafe/memset chunk shows up a lot in this series. Maybe it
should be a static inline within dax.c?
--D
> + }
> entry = dax_insert_entry(&xas, mapping, vmf, entry, pfn,
>0, write && !sync);
>
> @@ -1597,7 +1608,7 @@ 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_pfn(&iomap, pos, PMD_SIZE, &pfn, NULL);
> if (error < 0)
> goto finish_iomap;
>
> --
> 2.16.4
>
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[PATCH 08/18] dax: memcpy page in case of IOMAP_DAX_COW for mmap faults
From: Goldwyn Rodrigues
Change dax_iomap_pfn to return the address as well in order to
use it for performing a memcpy in case the type is IOMAP_DAX_COW.
We don't handle PMD because btrfs does not support hugepages.
Question:
The sequence of bdev_dax_pgoff() and dax_direct_access() is
used multiple times to calculate address and pfn's. Would it make
sense to call it while calculating address as well to reduce code?
Signed-off-by: Goldwyn Rodrigues
---
fs/dax.c | 19 +++
1 file changed, 15 insertions(+), 4 deletions(-)
diff --git a/fs/dax.c b/fs/dax.c
index 610bfa861a28..718b1632a39d 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -984,7 +984,7 @@ static sector_t dax_iomap_sector(struct iomap *iomap,
loff_t pos)
}
static int dax_iomap_pfn(struct iomap *iomap, loff_t pos, size_t size,
-pfn_t *pfnp)
+pfn_t *pfnp, void **addr)
{
const sector_t sector = dax_iomap_sector(iomap, pos);
pgoff_t pgoff;
@@ -996,7 +996,7 @@ 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);
+ addr, pfnp);
if (length < 0) {
rc = length;
goto out;
@@ -1286,6 +1286,7 @@ static vm_fault_t dax_iomap_pte_fault(struct vm_fault
*vmf, pfn_t *pfnp,
XA_STATE(xas, &mapping->i_pages, vmf->pgoff);
struct inode *inode = mapping->host;
unsigned long vaddr = vmf->address;
+ void *addr;
loff_t pos = (loff_t)vmf->pgoff << PAGE_SHIFT;
struct iomap iomap = { 0 };
unsigned flags = IOMAP_FAULT;
@@ -1375,16 +1376,26 @@ static vm_fault_t dax_iomap_pte_fault(struct vm_fault
*vmf, pfn_t *pfnp,
sync = dax_fault_is_synchronous(flags, vma, &iomap);
switch (iomap.type) {
+ case IOMAP_DAX_COW:
case IOMAP_MAPPED:
if (iomap.flags & IOMAP_F_NEW) {
count_vm_event(PGMAJFAULT);
count_memcg_event_mm(vma->vm_mm, PGMAJFAULT);
major = VM_FAULT_MAJOR;
}
- error = dax_iomap_pfn(&iomap, pos, PAGE_SIZE, &pfn);
+ error = dax_iomap_pfn(&iomap, pos, PAGE_SIZE, &pfn, &addr);
if (error < 0)
goto error_finish_iomap;
+ if (iomap.type == IOMAP_DAX_COW) {
+ if (iomap.inline_data) {
+ error = memcpy_mcsafe(addr, iomap.inline_data,
+ PAGE_SIZE);
+ if (error < 0)
+ goto error_finish_iomap;
+ } else
+ memset(addr, 0, PAGE_SIZE);
+ }
entry = dax_insert_entry(&xas, mapping, vmf, entry, pfn,
0, write && !sync);
@@ -1597,7 +1608,7 @@ 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_pfn(&iomap, pos, PMD_SIZE, &pfn, NULL);
if (error < 0)
goto finish_iomap;
--
2.16.4
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Re: [PATCH 08/18] dax: memcpy page in case of IOMAP_DAX_COW for mmap faults
On Tue, Apr 16, 2019 at 11:41:44AM -0500, Goldwyn Rodrigues wrote:
> From: Goldwyn Rodrigues
>
> Change dax_iomap_pfn to return the address as well in order to
> use it for performing a memcpy in case the type is IOMAP_DAX_COW.
>
> Question:
> The sequence of bdev_dax_pgoff() and dax_direct_access() is
> used multiple times to calculate address and pfn's. Would it make
> sense to call it while calculating address as well to reduce code?
>
> Signed-off-by: Goldwyn Rodrigues
> ---
> fs/dax.c | 16
> 1 file changed, 12 insertions(+), 4 deletions(-)
>
> diff --git a/fs/dax.c b/fs/dax.c
> index 4b4ac51fbd16..45fc2e18969a 100644
> --- a/fs/dax.c
> +++ b/fs/dax.c
> @@ -983,7 +983,7 @@ static sector_t dax_iomap_sector(struct iomap *iomap,
> loff_t pos)
> }
>
> static int dax_iomap_pfn(struct iomap *iomap, loff_t pos, size_t size,
> - pfn_t *pfnp)
> + pfn_t *pfnp, void **addr)
> {
> const sector_t sector = dax_iomap_sector(iomap, pos);
> pgoff_t pgoff;
> @@ -995,7 +995,7 @@ 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);
> +addr, pfnp);
> if (length < 0) {
> rc = length;
> goto out;
> @@ -1280,6 +1280,7 @@ static vm_fault_t dax_iomap_pte_fault(struct vm_fault
> *vmf, pfn_t *pfnp,
> XA_STATE(xas, &mapping->i_pages, vmf->pgoff);
> struct inode *inode = mapping->host;
> unsigned long vaddr = vmf->address;
> + void *addr;
> loff_t pos = (loff_t)vmf->pgoff << PAGE_SHIFT;
> struct iomap iomap = { 0 };
> unsigned flags = IOMAP_FAULT;
> @@ -1369,16 +1370,23 @@ static vm_fault_t dax_iomap_pte_fault(struct vm_fault
> *vmf, pfn_t *pfnp,
> sync = dax_fault_is_synchronous(flags, vma, &iomap);
>
> switch (iomap.type) {
> + case IOMAP_DAX_COW:
> case IOMAP_MAPPED:
> if (iomap.flags & IOMAP_F_NEW) {
> count_vm_event(PGMAJFAULT);
> count_memcg_event_mm(vma->vm_mm, PGMAJFAULT);
> major = VM_FAULT_MAJOR;
> }
> - error = dax_iomap_pfn(&iomap, pos, PAGE_SIZE, &pfn);
> + error = dax_iomap_pfn(&iomap, pos, PAGE_SIZE, &pfn, &addr);
> if (error < 0)
> goto error_finish_iomap;
>
> + if (iomap.type == IOMAP_DAX_COW) {
> + if (iomap.inline_data)
> + memcpy(addr, iomap.inline_data, PAGE_SIZE);
Same memcpy_mcsafe question from my reply to patch 4 applies here.
> + else
> + memset(addr, 0, PAGE_SIZE);
> + }
> entry = dax_insert_entry(&xas, mapping, vmf, entry, pfn,
>0, write && !sync);
>
> @@ -1577,7 +1585,7 @@ 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_pfn(&iomap, pos, PMD_SIZE, &pfn, NULL);
Same (unanswered) question from the v2 series -- doesn't a PMD fault
also require handling IOMAP_DAX_COW?
--D
> if (error < 0)
> goto finish_iomap;
>
> --
> 2.16.4
>
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[PATCH 08/18] dax: memcpy page in case of IOMAP_DAX_COW for mmap faults
From: Goldwyn Rodrigues
Change dax_iomap_pfn to return the address as well in order to
use it for performing a memcpy in case the type is IOMAP_DAX_COW.
Question:
The sequence of bdev_dax_pgoff() and dax_direct_access() is
used multiple times to calculate address and pfn's. Would it make
sense to call it while calculating address as well to reduce code?
Signed-off-by: Goldwyn Rodrigues
---
fs/dax.c | 16
1 file changed, 12 insertions(+), 4 deletions(-)
diff --git a/fs/dax.c b/fs/dax.c
index 4b4ac51fbd16..45fc2e18969a 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -983,7 +983,7 @@ static sector_t dax_iomap_sector(struct iomap *iomap,
loff_t pos)
}
static int dax_iomap_pfn(struct iomap *iomap, loff_t pos, size_t size,
-pfn_t *pfnp)
+pfn_t *pfnp, void **addr)
{
const sector_t sector = dax_iomap_sector(iomap, pos);
pgoff_t pgoff;
@@ -995,7 +995,7 @@ 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);
+ addr, pfnp);
if (length < 0) {
rc = length;
goto out;
@@ -1280,6 +1280,7 @@ static vm_fault_t dax_iomap_pte_fault(struct vm_fault
*vmf, pfn_t *pfnp,
XA_STATE(xas, &mapping->i_pages, vmf->pgoff);
struct inode *inode = mapping->host;
unsigned long vaddr = vmf->address;
+ void *addr;
loff_t pos = (loff_t)vmf->pgoff << PAGE_SHIFT;
struct iomap iomap = { 0 };
unsigned flags = IOMAP_FAULT;
@@ -1369,16 +1370,23 @@ static vm_fault_t dax_iomap_pte_fault(struct vm_fault
*vmf, pfn_t *pfnp,
sync = dax_fault_is_synchronous(flags, vma, &iomap);
switch (iomap.type) {
+ case IOMAP_DAX_COW:
case IOMAP_MAPPED:
if (iomap.flags & IOMAP_F_NEW) {
count_vm_event(PGMAJFAULT);
count_memcg_event_mm(vma->vm_mm, PGMAJFAULT);
major = VM_FAULT_MAJOR;
}
- error = dax_iomap_pfn(&iomap, pos, PAGE_SIZE, &pfn);
+ error = dax_iomap_pfn(&iomap, pos, PAGE_SIZE, &pfn, &addr);
if (error < 0)
goto error_finish_iomap;
+ if (iomap.type == IOMAP_DAX_COW) {
+ if (iomap.inline_data)
+ memcpy(addr, iomap.inline_data, PAGE_SIZE);
+ else
+ memset(addr, 0, PAGE_SIZE);
+ }
entry = dax_insert_entry(&xas, mapping, vmf, entry, pfn,
0, write && !sync);
@@ -1577,7 +1585,7 @@ 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_pfn(&iomap, pos, PMD_SIZE, &pfn, NULL);
if (error < 0)
goto finish_iomap;
--
2.16.4
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