From: Huaisheng Ye <[email protected]>
Changes since v1 [1]:
* Involve the previous patches for pfn can be NULL.
* Reword the patch descriptions according to Christian's comment.
* According to Ross's suggestion, replace local pointer dummy_addr
with NULL within md/dm-writecache for direct_access.
[1]: https://lkml.org/lkml/2018/7/24/199
Some functions within fs/dax, dax/super and md/dm-writecache don't
need to get local pointer kaddr or variable pfn from direct_access.
Assigning NULL to kaddr or pfn to ->direct_access() is more
straightforward and simple than offering a useless local pointer or
variable.
So all ->direct_access() need to check the validity of pointer kaddr
and pfn for NULL assignment. If either of them is equal to NULL, that
is to say callers may have no need for kaddr or pfn, so this series of
patch are prepared for allowing them to pass in NULL instead of having
to pass in a local pointer or variable that they then just throw away.
Huaisheng Ye (6):
libnvdimm, pmem: kaddr and pfn can be NULL to ->direct_access()
s390, dcssblk: kaddr and pfn can be NULL to ->direct_access()
tools/testing/nvdimm: kaddr and pfn can be NULL to ->direct_access()
dax/super: Do not request a pointer kaddr when not required
md/dm-writecache: Don't request pointer dummy_addr when not required
filesystem-dax: Do not request kaddr and pfn when not required
drivers/dax/super.c | 3 +--
drivers/md/dm-writecache.c | 3 +--
drivers/nvdimm/pmem.c | 7 +++++--
drivers/s390/block/dcssblk.c | 8 +++++---
fs/dax.c | 13 ++++---------
tools/testing/nvdimm/pmem-dax.c | 12 ++++++++----
6 files changed, 24 insertions(+), 22 deletions(-)
--
1.8.3.1
From: Huaisheng Ye <[email protected]>
The mock / test version of pmem_direct_access() needs to check the
validity of pointers kaddr and pfn for NULL assignment. If anyone
equals to NULL, it doesn't need to calculate the value.
If pointer equals to NULL, that is to say callers may have no need for
kaddr or pfn, so this patch is prepared for allowing them to pass in
NULL instead of having to pass in a local pointer or variable that
they then just throw away.
Suggested-by: Dan Williams <[email protected]>
Signed-off-by: Huaisheng Ye <[email protected]>
---
tools/testing/nvdimm/pmem-dax.c | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)
diff --git a/tools/testing/nvdimm/pmem-dax.c b/tools/testing/nvdimm/pmem-dax.c
index b53596a..2e7fd82 100644
--- a/tools/testing/nvdimm/pmem-dax.c
+++ b/tools/testing/nvdimm/pmem-dax.c
@@ -31,17 +31,21 @@ long __pmem_direct_access(struct pmem_device *pmem, pgoff_t pgoff,
if (get_nfit_res(pmem->phys_addr + offset)) {
struct page *page;
- *kaddr = pmem->virt_addr + offset;
+ if (kaddr)
+ *kaddr = pmem->virt_addr + offset;
page = vmalloc_to_page(pmem->virt_addr + offset);
- *pfn = page_to_pfn_t(page);
+ if (pfn)
+ *pfn = page_to_pfn_t(page);
pr_debug_ratelimited("%s: pmem: %p pgoff: %#lx pfn: %#lx\n",
__func__, pmem, pgoff, page_to_pfn(page));
return 1;
}
- *kaddr = pmem->virt_addr + offset;
- *pfn = phys_to_pfn_t(pmem->phys_addr + offset, pmem->pfn_flags);
+ if (kaddr)
+ *kaddr = pmem->virt_addr + offset;
+ if (pfn)
+ *pfn = phys_to_pfn_t(pmem->phys_addr + offset, pmem->pfn_flags);
/*
* If badblocks are present, limit known good range to the
--
1.8.3.1
From: Huaisheng Ye <[email protected]>
Function persistent_memory_claim doesn't need to get local pointer
dummy_addr from direct_access. Using NULL instead of having to pass
in a useless local pointer that caller then just throw away.
Suggested-by: Ross Zwisler <[email protected]>
Signed-off-by: Huaisheng Ye <[email protected]>
---
drivers/md/dm-writecache.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/drivers/md/dm-writecache.c b/drivers/md/dm-writecache.c
index 87107c9..9d79084 100644
--- a/drivers/md/dm-writecache.c
+++ b/drivers/md/dm-writecache.c
@@ -268,9 +268,8 @@ static int persistent_memory_claim(struct dm_writecache *wc)
i = 0;
do {
long daa;
- void *dummy_addr;
daa = dax_direct_access(wc->ssd_dev->dax_dev, i, p - i,
- &dummy_addr, &pfn);
+ NULL, &pfn);
if (daa <= 0) {
r = daa ? daa : -EINVAL;
goto err3;
--
1.8.3.1
From: Huaisheng Ye <[email protected]>
dcssblk_direct_access() needs to check the validity of pointers kaddr
and pfn for NULL assignment. If anyone equals to NULL, it doesn't need
to calculate the value.
If either of them is equal to NULL, that is to say callers may
have no need for kaddr or pfn, so this patch is prepared for allowing
them to pass in NULL instead of having to pass in a pointer or local
variable that they then just throw away.
Signed-off-by: Huaisheng Ye <[email protected]>
---
drivers/s390/block/dcssblk.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/drivers/s390/block/dcssblk.c b/drivers/s390/block/dcssblk.c
index ed60728..23e526c 100644
--- a/drivers/s390/block/dcssblk.c
+++ b/drivers/s390/block/dcssblk.c
@@ -922,9 +922,11 @@ static DEVICE_ATTR(save, S_IWUSR | S_IRUSR, dcssblk_save_show,
unsigned long dev_sz;
dev_sz = dev_info->end - dev_info->start + 1;
- *kaddr = (void *) dev_info->start + offset;
- *pfn = __pfn_to_pfn_t(PFN_DOWN(dev_info->start + offset),
- PFN_DEV|PFN_SPECIAL);
+ if (kaddr)
+ *kaddr = (void *) dev_info->start + offset;
+ if (pfn)
+ *pfn = __pfn_to_pfn_t(PFN_DOWN(dev_info->start + offset),
+ PFN_DEV|PFN_SPECIAL);
return (dev_sz - offset) / PAGE_SIZE;
}
--
1.8.3.1
From: Huaisheng Ye <[email protected]>
Function __bdev_dax_supported doesn't need to get local pointer kaddr
from direct_access. Using NULL instead of having to pass in a useless
local pointer that caller then just throw away.
Signed-off-by: Huaisheng Ye <[email protected]>
---
drivers/dax/super.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/drivers/dax/super.c b/drivers/dax/super.c
index 45276ab..6e928f3 100644
--- a/drivers/dax/super.c
+++ b/drivers/dax/super.c
@@ -89,7 +89,6 @@ bool __bdev_dax_supported(struct block_device *bdev, int blocksize)
struct request_queue *q;
pgoff_t pgoff;
int err, id;
- void *kaddr;
pfn_t pfn;
long len;
char buf[BDEVNAME_SIZE];
@@ -122,7 +121,7 @@ bool __bdev_dax_supported(struct block_device *bdev, int blocksize)
}
id = dax_read_lock();
- len = dax_direct_access(dax_dev, pgoff, 1, &kaddr, &pfn);
+ len = dax_direct_access(dax_dev, pgoff, 1, NULL, &pfn);
dax_read_unlock(id);
put_dax(dax_dev);
--
1.8.3.1
From: Huaisheng Ye <[email protected]>
Some functions within fs/dax don't need to get local pointer kaddr
or variable pfn from direct_access. Using NULL instead of having to
pass in useless pointer or variable that caller then just throw away.
Signed-off-by: Huaisheng Ye <[email protected]>
---
fs/dax.c | 13 ++++---------
1 file changed, 4 insertions(+), 9 deletions(-)
diff --git a/fs/dax.c b/fs/dax.c
index 6411928..959a533 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -647,7 +647,6 @@ static int copy_user_dax(struct block_device *bdev, struct dax_device *dax_dev,
{
void *vto, *kaddr;
pgoff_t pgoff;
- pfn_t pfn;
long rc;
int id;
@@ -656,7 +655,7 @@ static int copy_user_dax(struct block_device *bdev, struct dax_device *dax_dev,
return rc;
id = dax_read_lock();
- rc = dax_direct_access(dax_dev, pgoff, PHYS_PFN(size), &kaddr, &pfn);
+ rc = dax_direct_access(dax_dev, pgoff, PHYS_PFN(size), &kaddr, NULL);
if (rc < 0) {
dax_read_unlock(id);
return rc;
@@ -967,7 +966,6 @@ static int dax_iomap_pfn(struct iomap *iomap, loff_t pos, size_t size,
{
const sector_t sector = dax_iomap_sector(iomap, pos);
pgoff_t pgoff;
- void *kaddr;
int id, rc;
long length;
@@ -976,7 +974,7 @@ 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),
- &kaddr, pfnp);
+ NULL, pfnp);
if (length < 0) {
rc = length;
goto out;
@@ -1052,15 +1050,13 @@ int __dax_zero_page_range(struct block_device *bdev,
pgoff_t pgoff;
long rc, id;
void *kaddr;
- pfn_t pfn;
rc = bdev_dax_pgoff(bdev, sector, PAGE_SIZE, &pgoff);
if (rc)
return rc;
id = dax_read_lock();
- rc = dax_direct_access(dax_dev, pgoff, 1, &kaddr,
- &pfn);
+ rc = dax_direct_access(dax_dev, pgoff, 1, &kaddr, NULL);
if (rc < 0) {
dax_read_unlock(id);
return rc;
@@ -1116,7 +1112,6 @@ int __dax_zero_page_range(struct block_device *bdev,
ssize_t map_len;
pgoff_t pgoff;
void *kaddr;
- pfn_t pfn;
if (fatal_signal_pending(current)) {
ret = -EINTR;
@@ -1128,7 +1123,7 @@ int __dax_zero_page_range(struct block_device *bdev,
break;
map_len = dax_direct_access(dax_dev, pgoff, PHYS_PFN(size),
- &kaddr, &pfn);
+ &kaddr, NULL);
if (map_len < 0) {
ret = map_len;
break;
--
1.8.3.1
From: Huaisheng Ye <[email protected]>
pmem_direct_access() needs to check the validity of pointers kaddr
and pfn for NULL assignment. If anyone equals to NULL, it doesn't need
to calculate the value.
If pointer equals to NULL, that is to say callers may have no need for
kaddr or pfn, so this patch is prepared for allowing them to pass in
NULL instead of having to pass in a pointer or local variable that
they then just throw away.
Signed-off-by: Huaisheng Ye <[email protected]>
---
drivers/nvdimm/pmem.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c
index 8b1fd7f..ecf9024 100644
--- a/drivers/nvdimm/pmem.c
+++ b/drivers/nvdimm/pmem.c
@@ -227,8 +227,11 @@ __weak long __pmem_direct_access(struct pmem_device *pmem, pgoff_t pgoff,
if (unlikely(is_bad_pmem(&pmem->bb, PFN_PHYS(pgoff) / 512,
PFN_PHYS(nr_pages))))
return -EIO;
- *kaddr = pmem->virt_addr + offset;
- *pfn = phys_to_pfn_t(pmem->phys_addr + offset, pmem->pfn_flags);
+
+ if (kaddr)
+ *kaddr = pmem->virt_addr + offset;
+ if (pfn)
+ *pfn = phys_to_pfn_t(pmem->phys_addr + offset, pmem->pfn_flags);
/*
* If badblocks are present, limit known good range to the
--
1.8.3.1
On Thu, Jul 26, 2018 at 12:28:43AM +0800, Huaisheng Ye wrote:
> From: Huaisheng Ye <[email protected]>
>
> Changes since v1 [1]:
> * Involve the previous patches for pfn can be NULL.
> * Reword the patch descriptions according to Christian's comment.
> * According to Ross's suggestion, replace local pointer dummy_addr
> with NULL within md/dm-writecache for direct_access.
>
> [1]: https://lkml.org/lkml/2018/7/24/199
>
> Some functions within fs/dax, dax/super and md/dm-writecache don't
> need to get local pointer kaddr or variable pfn from direct_access.
> Assigning NULL to kaddr or pfn to ->direct_access() is more
> straightforward and simple than offering a useless local pointer or
> variable.
>
> So all ->direct_access() need to check the validity of pointer kaddr
> and pfn for NULL assignment. If either of them is equal to NULL, that
> is to say callers may have no need for kaddr or pfn, so this series of
> patch are prepared for allowing them to pass in NULL instead of having
> to pass in a local pointer or variable that they then just throw away.
Looks good. For the series:
Reviewed-by: Ross Zwisler <[email protected]>
Pretty straight forward series. Huaisheng, I can apply the whole series
to libnvdimm if we can get ack's from maintainer of dcssblk and
dm-writecache for the respective bits.
On 07/25/2018 09:28 AM, Huaisheng Ye wrote:
> From: Huaisheng Ye <[email protected]>
>
> Changes since v1 [1]:
> * Involve the previous patches for pfn can be NULL.
> * Reword the patch descriptions according to Christian's comment.
> * According to Ross's suggestion, replace local pointer dummy_addr
> with NULL within md/dm-writecache for direct_access.
>
> [1]: https://lkml.org/lkml/2018/7/24/199
>
> Some functions within fs/dax, dax/super and md/dm-writecache don't
> need to get local pointer kaddr or variable pfn from direct_access.
> Assigning NULL to kaddr or pfn to ->direct_access() is more
> straightforward and simple than offering a useless local pointer or
> variable.
>
> So all ->direct_access() need to check the validity of pointer kaddr
> and pfn for NULL assignment. If either of them is equal to NULL, that
> is to say callers may have no need for kaddr or pfn, so this series of
> patch are prepared for allowing them to pass in NULL instead of having
> to pass in a local pointer or variable that they then just throw away.
>
> Huaisheng Ye (6):
> libnvdimm, pmem: kaddr and pfn can be NULL to ->direct_access()
> s390, dcssblk: kaddr and pfn can be NULL to ->direct_access()
> tools/testing/nvdimm: kaddr and pfn can be NULL to ->direct_access()
> dax/super: Do not request a pointer kaddr when not required
> md/dm-writecache: Don't request pointer dummy_addr when not required
> filesystem-dax: Do not request kaddr and pfn when not required
>
> drivers/dax/super.c | 3 +--
> drivers/md/dm-writecache.c | 3 +--
> drivers/nvdimm/pmem.c | 7 +++++--
> drivers/s390/block/dcssblk.c | 8 +++++---
> fs/dax.c | 13 ++++---------
> tools/testing/nvdimm/pmem-dax.c | 12 ++++++++----
> 6 files changed, 24 insertions(+), 22 deletions(-)
>
> From: Dave Jiang <[email protected]>
> Sent: Thursday, July 26, 2018 5:36 AM
> Subject: [External] Re: [PATCH v2 0/6] kaddr and pfn can be NULL to ->direct_access()
>
> Pretty straight forward series. Huaisheng, I can apply the whole series
> to libnvdimm if we can get ack's from maintainer of dcssblk and
> dm-writecache for the respective bits.
Thanks Dave and Ross.
Hi Jan an Dan,
The previous patch series for NULL-pfn had got your Reviewed-by or Signed-off-by.
Now I have expanded them to local pointer kaddr, can I get your Reviewed-by for current
patch series? Your acks are very important to me.
Cheers,
Huaisheng Ye
On Wed, Jul 25 2018 at 12:28pm -0400,
Huaisheng Ye <[email protected]> wrote:
> From: Huaisheng Ye <[email protected]>
>
> Function persistent_memory_claim doesn't need to get local pointer
> dummy_addr from direct_access. Using NULL instead of having to pass
> in a useless local pointer that caller then just throw away.
>
> Suggested-by: Ross Zwisler <[email protected]>
> Signed-off-by: Huaisheng Ye <[email protected]>
Acked-by: Mike Snitzer <[email protected]>
Dear Maintainers of Linux-s390,
Greetings.
May I have your ack's for this patch? The whole series would be applied
to libnvdimm if it could get your approval.
And any suggestion is welcome.
Cheers,
Huaisheng Ye
> From: Huaisheng Ye <[email protected]>
> Sent: Thursday, July 26, 2018 12:29 AM
>
> From: Huaisheng Ye <[email protected]>
>
> dcssblk_direct_access() needs to check the validity of pointers kaddr
> and pfn for NULL assignment. If anyone equals to NULL, it doesn't need
> to calculate the value.
>
> If either of them is equal to NULL, that is to say callers may
> have no need for kaddr or pfn, so this patch is prepared for allowing
> them to pass in NULL instead of having to pass in a pointer or local
> variable that they then just throw away.
>
> Signed-off-by: Huaisheng Ye <[email protected]>
> ---
> drivers/s390/block/dcssblk.c | 8 +++++---
> 1 file changed, 5 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/s390/block/dcssblk.c b/drivers/s390/block/dcssblk.c
> index ed60728..23e526c 100644
> --- a/drivers/s390/block/dcssblk.c
> +++ b/drivers/s390/block/dcssblk.c
> @@ -922,9 +922,11 @@ static DEVICE_ATTR(save, S_IWUSR | S_IRUSR, dcssblk_save_show,
> unsigned long dev_sz;
>
> dev_sz = dev_info->end - dev_info->start + 1;
> - *kaddr = (void *) dev_info->start + offset;
> - *pfn = __pfn_to_pfn_t(PFN_DOWN(dev_info->start + offset),
> - PFN_DEV|PFN_SPECIAL);
> + if (kaddr)
> + *kaddr = (void *) dev_info->start + offset;
> + if (pfn)
> + *pfn = __pfn_to_pfn_t(PFN_DOWN(dev_info->start + offset),
> + PFN_DEV|PFN_SPECIAL);
>
> return (dev_sz - offset) / PAGE_SIZE;
> }
> --
> 1.8.3.1
On Sat, 28 Jul 2018 04:07:25 +0000
Huaisheng HS1 Ye <[email protected]> wrote:
> May I have your ack's for this patch? The whole series would be applied
> to libnvdimm if it could get your approval.
> And any suggestion is welcome.
Sure, it is just two additional ifs. I did not think that this needed an
ack, but here you go:
Acked-by: Martin Schwidefsky <[email protected]>
>
> Cheers,
> Huaisheng Ye
>
> > From: Huaisheng Ye <[email protected]>
> > Sent: Thursday, July 26, 2018 12:29 AM
> >
> > From: Huaisheng Ye <[email protected]>
> >
> > dcssblk_direct_access() needs to check the validity of pointers kaddr
> > and pfn for NULL assignment. If anyone equals to NULL, it doesn't need
> > to calculate the value.
> >
> > If either of them is equal to NULL, that is to say callers may
> > have no need for kaddr or pfn, so this patch is prepared for allowing
> > them to pass in NULL instead of having to pass in a pointer or local
> > variable that they then just throw away.
> >
> > Signed-off-by: Huaisheng Ye <[email protected]>
> > ---
> > drivers/s390/block/dcssblk.c | 8 +++++---
> > 1 file changed, 5 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/s390/block/dcssblk.c b/drivers/s390/block/dcssblk.c
> > index ed60728..23e526c 100644
> > --- a/drivers/s390/block/dcssblk.c
> > +++ b/drivers/s390/block/dcssblk.c
> > @@ -922,9 +922,11 @@ static DEVICE_ATTR(save, S_IWUSR | S_IRUSR, dcssblk_save_show,
> > unsigned long dev_sz;
> >
> > dev_sz = dev_info->end - dev_info->start + 1;
> > - *kaddr = (void *) dev_info->start + offset;
> > - *pfn = __pfn_to_pfn_t(PFN_DOWN(dev_info->start + offset),
> > - PFN_DEV|PFN_SPECIAL);
> > + if (kaddr)
> > + *kaddr = (void *) dev_info->start + offset;
> > + if (pfn)
> > + *pfn = __pfn_to_pfn_t(PFN_DOWN(dev_info->start + offset),
> > + PFN_DEV|PFN_SPECIAL);
> >
> > return (dev_sz - offset) / PAGE_SIZE;
> > }
> > --
> > 1.8.3.1
>
--
blue skies,
Martin.
"Reality continues to ruin my life." - Calvin.