[v9,1/7] libnvdimm: nd_region flush callback support
diff mbox series

Message ID 20190514145422.16923-2-pagupta@redhat.com
State Superseded
Headers show
Series
  • virtio pmem driver
Related show

Commit Message

Pankaj Gupta May 14, 2019, 2:54 p.m. UTC
This patch adds functionality to perform flush from guest
to host over VIRTIO. We are registering a callback based
on 'nd_region' type. virtio_pmem driver requires this special
flush function. For rest of the region types we are registering
existing flush function. Report error returned by host fsync
failure to userspace.

Signed-off-by: Pankaj Gupta <pagupta@redhat.com>
---
 drivers/acpi/nfit/core.c     |  4 ++--
 drivers/nvdimm/claim.c       |  6 ++++--
 drivers/nvdimm/nd.h          |  1 +
 drivers/nvdimm/pmem.c        | 13 ++++++++-----
 drivers/nvdimm/region_devs.c | 26 ++++++++++++++++++++++++--
 include/linux/libnvdimm.h    |  8 +++++++-
 6 files changed, 46 insertions(+), 12 deletions(-)

Comments

Dan Williams May 15, 2019, 9:07 p.m. UTC | #1
On Tue, May 14, 2019 at 7:55 AM Pankaj Gupta <pagupta@redhat.com> wrote:
>
> This patch adds functionality to perform flush from guest
> to host over VIRTIO. We are registering a callback based
> on 'nd_region' type. virtio_pmem driver requires this special
> flush function. For rest of the region types we are registering
> existing flush function. Report error returned by host fsync
> failure to userspace.
>
> Signed-off-by: Pankaj Gupta <pagupta@redhat.com>
> ---
>  drivers/acpi/nfit/core.c     |  4 ++--
>  drivers/nvdimm/claim.c       |  6 ++++--
>  drivers/nvdimm/nd.h          |  1 +
>  drivers/nvdimm/pmem.c        | 13 ++++++++-----
>  drivers/nvdimm/region_devs.c | 26 ++++++++++++++++++++++++--
>  include/linux/libnvdimm.h    |  8 +++++++-
>  6 files changed, 46 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c
> index 5a389a4f4f65..08dde76cf459 100644
> --- a/drivers/acpi/nfit/core.c
> +++ b/drivers/acpi/nfit/core.c
> @@ -2434,7 +2434,7 @@ static void write_blk_ctl(struct nfit_blk *nfit_blk, unsigned int bw,
>                 offset = to_interleave_offset(offset, mmio);
>
>         writeq(cmd, mmio->addr.base + offset);
> -       nvdimm_flush(nfit_blk->nd_region);
> +       nvdimm_flush(nfit_blk->nd_region, NULL);
>
>         if (nfit_blk->dimm_flags & NFIT_BLK_DCR_LATCH)
>                 readq(mmio->addr.base + offset);
> @@ -2483,7 +2483,7 @@ static int acpi_nfit_blk_single_io(struct nfit_blk *nfit_blk,
>         }
>
>         if (rw)
> -               nvdimm_flush(nfit_blk->nd_region);
> +               nvdimm_flush(nfit_blk->nd_region, NULL);
>
>         rc = read_blk_stat(nfit_blk, lane) ? -EIO : 0;
>         return rc;
> diff --git a/drivers/nvdimm/claim.c b/drivers/nvdimm/claim.c
> index fb667bf469c7..13510bae1e6f 100644
> --- a/drivers/nvdimm/claim.c
> +++ b/drivers/nvdimm/claim.c
> @@ -263,7 +263,7 @@ static int nsio_rw_bytes(struct nd_namespace_common *ndns,
>         struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev);
>         unsigned int sz_align = ALIGN(size + (offset & (512 - 1)), 512);
>         sector_t sector = offset >> 9;
> -       int rc = 0;
> +       int rc = 0, ret = 0;
>
>         if (unlikely(!size))
>                 return 0;
> @@ -301,7 +301,9 @@ static int nsio_rw_bytes(struct nd_namespace_common *ndns,
>         }
>
>         memcpy_flushcache(nsio->addr + offset, buf, size);
> -       nvdimm_flush(to_nd_region(ndns->dev.parent));
> +       ret = nvdimm_flush(to_nd_region(ndns->dev.parent), NULL);
> +       if (ret)
> +               rc = ret;
>
>         return rc;
>  }
> diff --git a/drivers/nvdimm/nd.h b/drivers/nvdimm/nd.h
> index a5ac3b240293..0c74d2428bd7 100644
> --- a/drivers/nvdimm/nd.h
> +++ b/drivers/nvdimm/nd.h
> @@ -159,6 +159,7 @@ struct nd_region {
>         struct badblocks bb;
>         struct nd_interleave_set *nd_set;
>         struct nd_percpu_lane __percpu *lane;
> +       int (*flush)(struct nd_region *nd_region, struct bio *bio);

So this triggers:

In file included from drivers/nvdimm/e820.c:7:
./include/linux/libnvdimm.h:140:51: warning: ‘struct bio’ declared
inside parameter list will not be visible outside of this definition
or declaration
  int (*flush)(struct nd_region *nd_region, struct bio *bio);
                                                   ^~~
I was already feeling uneasy about trying to squeeze this into v5.2,
but this warning and the continued drip of comments leads me to
conclude that this driver would do well to wait one more development
cycle. Lets close out the final fixups and let this driver soak in
-next. Then for the v5.3 cycle I'll redouble my efforts towards the
goal of closing patch acceptance at the -rc6 / -rc7 development
milestone.
Pankaj Gupta May 16, 2019, 6:28 a.m. UTC | #2
> >
> > This patch adds functionality to perform flush from guest
> > to host over VIRTIO. We are registering a callback based
> > on 'nd_region' type. virtio_pmem driver requires this special
> > flush function. For rest of the region types we are registering
> > existing flush function. Report error returned by host fsync
> > failure to userspace.
> >
> > Signed-off-by: Pankaj Gupta <pagupta@redhat.com>
> > ---
> >  drivers/acpi/nfit/core.c     |  4 ++--
> >  drivers/nvdimm/claim.c       |  6 ++++--
> >  drivers/nvdimm/nd.h          |  1 +
> >  drivers/nvdimm/pmem.c        | 13 ++++++++-----
> >  drivers/nvdimm/region_devs.c | 26 ++++++++++++++++++++++++--
> >  include/linux/libnvdimm.h    |  8 +++++++-
> >  6 files changed, 46 insertions(+), 12 deletions(-)
> >
> > diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c
> > index 5a389a4f4f65..08dde76cf459 100644
> > --- a/drivers/acpi/nfit/core.c
> > +++ b/drivers/acpi/nfit/core.c
> > @@ -2434,7 +2434,7 @@ static void write_blk_ctl(struct nfit_blk *nfit_blk,
> > unsigned int bw,
> >                 offset = to_interleave_offset(offset, mmio);
> >
> >         writeq(cmd, mmio->addr.base + offset);
> > -       nvdimm_flush(nfit_blk->nd_region);
> > +       nvdimm_flush(nfit_blk->nd_region, NULL);
> >
> >         if (nfit_blk->dimm_flags & NFIT_BLK_DCR_LATCH)
> >                 readq(mmio->addr.base + offset);
> > @@ -2483,7 +2483,7 @@ static int acpi_nfit_blk_single_io(struct nfit_blk
> > *nfit_blk,
> >         }
> >
> >         if (rw)
> > -               nvdimm_flush(nfit_blk->nd_region);
> > +               nvdimm_flush(nfit_blk->nd_region, NULL);
> >
> >         rc = read_blk_stat(nfit_blk, lane) ? -EIO : 0;
> >         return rc;
> > diff --git a/drivers/nvdimm/claim.c b/drivers/nvdimm/claim.c
> > index fb667bf469c7..13510bae1e6f 100644
> > --- a/drivers/nvdimm/claim.c
> > +++ b/drivers/nvdimm/claim.c
> > @@ -263,7 +263,7 @@ static int nsio_rw_bytes(struct nd_namespace_common
> > *ndns,
> >         struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev);
> >         unsigned int sz_align = ALIGN(size + (offset & (512 - 1)), 512);
> >         sector_t sector = offset >> 9;
> > -       int rc = 0;
> > +       int rc = 0, ret = 0;
> >
> >         if (unlikely(!size))
> >                 return 0;
> > @@ -301,7 +301,9 @@ static int nsio_rw_bytes(struct nd_namespace_common
> > *ndns,
> >         }
> >
> >         memcpy_flushcache(nsio->addr + offset, buf, size);
> > -       nvdimm_flush(to_nd_region(ndns->dev.parent));
> > +       ret = nvdimm_flush(to_nd_region(ndns->dev.parent), NULL);
> > +       if (ret)
> > +               rc = ret;
> >
> >         return rc;
> >  }
> > diff --git a/drivers/nvdimm/nd.h b/drivers/nvdimm/nd.h
> > index a5ac3b240293..0c74d2428bd7 100644
> > --- a/drivers/nvdimm/nd.h
> > +++ b/drivers/nvdimm/nd.h
> > @@ -159,6 +159,7 @@ struct nd_region {
> >         struct badblocks bb;
> >         struct nd_interleave_set *nd_set;
> >         struct nd_percpu_lane __percpu *lane;
> > +       int (*flush)(struct nd_region *nd_region, struct bio *bio);
> 
> So this triggers:
> 
> In file included from drivers/nvdimm/e820.c:7:
> ./include/linux/libnvdimm.h:140:51: warning: ‘struct bio’ declared
> inside parameter list will not be visible outside of this definition
> or declaration
>   int (*flush)(struct nd_region *nd_region, struct bio *bio);
>                                                    ^~~

Sorry! for this. Fixed now.

> I was already feeling uneasy about trying to squeeze this into v5.2,
> but this warning and the continued drip of comments leads me to
> conclude that this driver would do well to wait one more development
> cycle. Lets close out the final fixups and let this driver soak in
> -next. Then for the v5.3 cycle I'll redouble my efforts towards the
> goal of closing patch acceptance at the -rc6 / -rc7 development
> milestone.

o.k. Will wait for Mike's ACK on device mapper patch and send the v10
with final fix-ups. Thank you for your help.

Best regards,
Pankaj



>

Patch
diff mbox series

diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c
index 5a389a4f4f65..08dde76cf459 100644
--- a/drivers/acpi/nfit/core.c
+++ b/drivers/acpi/nfit/core.c
@@ -2434,7 +2434,7 @@  static void write_blk_ctl(struct nfit_blk *nfit_blk, unsigned int bw,
 		offset = to_interleave_offset(offset, mmio);
 
 	writeq(cmd, mmio->addr.base + offset);
-	nvdimm_flush(nfit_blk->nd_region);
+	nvdimm_flush(nfit_blk->nd_region, NULL);
 
 	if (nfit_blk->dimm_flags & NFIT_BLK_DCR_LATCH)
 		readq(mmio->addr.base + offset);
@@ -2483,7 +2483,7 @@  static int acpi_nfit_blk_single_io(struct nfit_blk *nfit_blk,
 	}
 
 	if (rw)
-		nvdimm_flush(nfit_blk->nd_region);
+		nvdimm_flush(nfit_blk->nd_region, NULL);
 
 	rc = read_blk_stat(nfit_blk, lane) ? -EIO : 0;
 	return rc;
diff --git a/drivers/nvdimm/claim.c b/drivers/nvdimm/claim.c
index fb667bf469c7..13510bae1e6f 100644
--- a/drivers/nvdimm/claim.c
+++ b/drivers/nvdimm/claim.c
@@ -263,7 +263,7 @@  static int nsio_rw_bytes(struct nd_namespace_common *ndns,
 	struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev);
 	unsigned int sz_align = ALIGN(size + (offset & (512 - 1)), 512);
 	sector_t sector = offset >> 9;
-	int rc = 0;
+	int rc = 0, ret = 0;
 
 	if (unlikely(!size))
 		return 0;
@@ -301,7 +301,9 @@  static int nsio_rw_bytes(struct nd_namespace_common *ndns,
 	}
 
 	memcpy_flushcache(nsio->addr + offset, buf, size);
-	nvdimm_flush(to_nd_region(ndns->dev.parent));
+	ret = nvdimm_flush(to_nd_region(ndns->dev.parent), NULL);
+	if (ret)
+		rc = ret;
 
 	return rc;
 }
diff --git a/drivers/nvdimm/nd.h b/drivers/nvdimm/nd.h
index a5ac3b240293..0c74d2428bd7 100644
--- a/drivers/nvdimm/nd.h
+++ b/drivers/nvdimm/nd.h
@@ -159,6 +159,7 @@  struct nd_region {
 	struct badblocks bb;
 	struct nd_interleave_set *nd_set;
 	struct nd_percpu_lane __percpu *lane;
+	int (*flush)(struct nd_region *nd_region, struct bio *bio);
 	struct nd_mapping mapping[0];
 };
 
diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c
index bc2f700feef8..f719245da170 100644
--- a/drivers/nvdimm/pmem.c
+++ b/drivers/nvdimm/pmem.c
@@ -192,6 +192,7 @@  static blk_status_t pmem_do_bvec(struct pmem_device *pmem, struct page *page,
 
 static blk_qc_t pmem_make_request(struct request_queue *q, struct bio *bio)
 {
+	int ret = 0;
 	blk_status_t rc = 0;
 	bool do_acct;
 	unsigned long start;
@@ -201,7 +202,7 @@  static blk_qc_t pmem_make_request(struct request_queue *q, struct bio *bio)
 	struct nd_region *nd_region = to_region(pmem);
 
 	if (bio->bi_opf & REQ_PREFLUSH)
-		nvdimm_flush(nd_region);
+		ret = nvdimm_flush(nd_region, bio);
 
 	do_acct = nd_iostat_start(bio, &start);
 	bio_for_each_segment(bvec, bio, iter) {
@@ -216,7 +217,10 @@  static blk_qc_t pmem_make_request(struct request_queue *q, struct bio *bio)
 		nd_iostat_end(bio, start);
 
 	if (bio->bi_opf & REQ_FUA)
-		nvdimm_flush(nd_region);
+		ret = nvdimm_flush(nd_region, bio);
+
+	if (ret)
+		bio->bi_status = errno_to_blk_status(ret);
 
 	bio_endio(bio);
 	return BLK_QC_T_NONE;
@@ -469,7 +473,6 @@  static int pmem_attach_disk(struct device *dev,
 	}
 	dax_write_cache(dax_dev, nvdimm_has_cache(nd_region));
 	pmem->dax_dev = dax_dev;
-
 	gendev = disk_to_dev(disk);
 	gendev->groups = pmem_attribute_groups;
 
@@ -527,14 +530,14 @@  static int nd_pmem_remove(struct device *dev)
 		sysfs_put(pmem->bb_state);
 		pmem->bb_state = NULL;
 	}
-	nvdimm_flush(to_nd_region(dev->parent));
+	nvdimm_flush(to_nd_region(dev->parent), NULL);
 
 	return 0;
 }
 
 static void nd_pmem_shutdown(struct device *dev)
 {
-	nvdimm_flush(to_nd_region(dev->parent));
+	nvdimm_flush(to_nd_region(dev->parent), NULL);
 }
 
 static void nd_pmem_notify(struct device *dev, enum nvdimm_event event)
diff --git a/drivers/nvdimm/region_devs.c b/drivers/nvdimm/region_devs.c
index b4ef7d9ff22e..e5b59708865e 100644
--- a/drivers/nvdimm/region_devs.c
+++ b/drivers/nvdimm/region_devs.c
@@ -295,7 +295,9 @@  static ssize_t deep_flush_store(struct device *dev, struct device_attribute *att
 		return rc;
 	if (!flush)
 		return -EINVAL;
-	nvdimm_flush(nd_region);
+	rc = nvdimm_flush(nd_region, NULL);
+	if (rc)
+		return rc;
 
 	return len;
 }
@@ -1085,6 +1087,11 @@  static struct nd_region *nd_region_create(struct nvdimm_bus *nvdimm_bus,
 	dev->of_node = ndr_desc->of_node;
 	nd_region->ndr_size = resource_size(ndr_desc->res);
 	nd_region->ndr_start = ndr_desc->res->start;
+	if (ndr_desc->flush)
+		nd_region->flush = ndr_desc->flush;
+	else
+		nd_region->flush = NULL;
+
 	nd_device_register(dev);
 
 	return nd_region;
@@ -1125,11 +1132,24 @@  struct nd_region *nvdimm_volatile_region_create(struct nvdimm_bus *nvdimm_bus,
 }
 EXPORT_SYMBOL_GPL(nvdimm_volatile_region_create);
 
+int nvdimm_flush(struct nd_region *nd_region, struct bio *bio)
+{
+	int rc = 0;
+
+	if (!nd_region->flush)
+		rc = generic_nvdimm_flush(nd_region);
+	else {
+		if (nd_region->flush(nd_region, bio))
+			rc = -EIO;
+	}
+
+	return rc;
+}
 /**
  * nvdimm_flush - flush any posted write queues between the cpu and pmem media
  * @nd_region: blk or interleaved pmem region
  */
-void nvdimm_flush(struct nd_region *nd_region)
+int generic_nvdimm_flush(struct nd_region *nd_region)
 {
 	struct nd_region_data *ndrd = dev_get_drvdata(&nd_region->dev);
 	int i, idx;
@@ -1153,6 +1173,8 @@  void nvdimm_flush(struct nd_region *nd_region)
 		if (ndrd_get_flush_wpq(ndrd, i, 0))
 			writeq(1, ndrd_get_flush_wpq(ndrd, i, idx));
 	wmb();
+
+	return 0;
 }
 EXPORT_SYMBOL_GPL(nvdimm_flush);
 
diff --git a/include/linux/libnvdimm.h b/include/linux/libnvdimm.h
index feb342d026f2..a5f369ec3726 100644
--- a/include/linux/libnvdimm.h
+++ b/include/linux/libnvdimm.h
@@ -65,6 +65,9 @@  enum {
 	 */
 	ND_REGION_PERSIST_MEMCTRL = 2,
 
+	/* Platform provides asynchronous flush mechanism */
+	ND_REGION_ASYNC = 3,
+
 	/* mark newly adjusted resources as requiring a label update */
 	DPA_RESOURCE_ADJUSTED = 1 << 0,
 };
@@ -121,6 +124,7 @@  struct nd_mapping_desc {
 	int position;
 };
 
+struct nd_region;
 struct nd_region_desc {
 	struct resource *res;
 	struct nd_mapping_desc *mapping;
@@ -133,6 +137,7 @@  struct nd_region_desc {
 	int target_node;
 	unsigned long flags;
 	struct device_node *of_node;
+	int (*flush)(struct nd_region *nd_region, struct bio *bio);
 };
 
 struct device;
@@ -260,7 +265,8 @@  unsigned long nd_blk_memremap_flags(struct nd_blk_region *ndbr);
 unsigned int nd_region_acquire_lane(struct nd_region *nd_region);
 void nd_region_release_lane(struct nd_region *nd_region, unsigned int lane);
 u64 nd_fletcher64(void *addr, size_t len, bool le);
-void nvdimm_flush(struct nd_region *nd_region);
+int nvdimm_flush(struct nd_region *nd_region, struct bio *bio);
+int generic_nvdimm_flush(struct nd_region *nd_region);
 int nvdimm_has_flush(struct nd_region *nd_region);
 int nvdimm_has_cache(struct nd_region *nd_region);
 int nvdimm_in_overwrite(struct nvdimm *nvdimm);