[3/5] dm,dax: Add dax zero_page_range operation
diff mbox series

Message ID 20200203200029.4592-4-vgoyal@redhat.com
State Superseded
Headers show
Series
  • dax,pmem: Provide a dax operation to zero range of memory
Related show

Commit Message

Vivek Goyal Feb. 3, 2020, 8 p.m. UTC
This patch adds support for dax zero_page_range operation to dm targets.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
---
 drivers/md/dm-linear.c        | 18 ++++++++++++++++++
 drivers/md/dm-log-writes.c    | 17 +++++++++++++++++
 drivers/md/dm-stripe.c        | 23 +++++++++++++++++++++++
 drivers/md/dm.c               | 30 ++++++++++++++++++++++++++++++
 include/linux/device-mapper.h |  3 +++
 5 files changed, 91 insertions(+)

Comments

hch@infradead.org Feb. 5, 2020, 6:33 p.m. UTC | #1
On Mon, Feb 03, 2020 at 03:00:27PM -0500, Vivek Goyal wrote:
> This patch adds support for dax zero_page_range operation to dm targets.

Any way to share the code with the dax copy iter here?
Vivek Goyal Feb. 7, 2020, 4:34 p.m. UTC | #2
On Wed, Feb 05, 2020 at 10:33:04AM -0800, Christoph Hellwig wrote:
> On Mon, Feb 03, 2020 at 03:00:27PM -0500, Vivek Goyal wrote:
> > This patch adds support for dax zero_page_range operation to dm targets.
> 
> Any way to share the code with the dax copy iter here?

Had a look at it and can't think of a good way of sharing the code. If
you have something specific in mind, I am happy to make changes.

Vivek

Patch
diff mbox series

diff --git a/drivers/md/dm-linear.c b/drivers/md/dm-linear.c
index 8d07fdf63a47..a6db998f0264 100644
--- a/drivers/md/dm-linear.c
+++ b/drivers/md/dm-linear.c
@@ -201,10 +201,27 @@  static size_t linear_dax_copy_to_iter(struct dm_target *ti, pgoff_t pgoff,
 	return dax_copy_to_iter(dax_dev, pgoff, addr, bytes, i);
 }
 
+static int linear_dax_zero_page_range(struct dm_target *ti, pgoff_t pgoff,
+		unsigned offset, size_t len)
+{
+	int ret;
+	struct linear_c *lc = ti->private;
+	struct block_device *bdev = lc->dev->bdev;
+	struct dax_device *dax_dev = lc->dev->dax_dev;
+	sector_t dev_sector, sector = pgoff * PAGE_SECTORS;
+
+	dev_sector = linear_map_sector(ti, sector);
+	ret = bdev_dax_pgoff(bdev, dev_sector, ALIGN(len, PAGE_SIZE), &pgoff);
+	if (ret)
+		return ret;
+	return dax_zero_page_range(dax_dev, pgoff, offset, len);
+}
+
 #else
 #define linear_dax_direct_access NULL
 #define linear_dax_copy_from_iter NULL
 #define linear_dax_copy_to_iter NULL
+#define linear_dax_zero_page_range NULL
 #endif
 
 static struct target_type linear_target = {
@@ -226,6 +243,7 @@  static struct target_type linear_target = {
 	.direct_access = linear_dax_direct_access,
 	.dax_copy_from_iter = linear_dax_copy_from_iter,
 	.dax_copy_to_iter = linear_dax_copy_to_iter,
+	.dax_zero_page_range = linear_dax_zero_page_range,
 };
 
 int __init dm_linear_init(void)
diff --git a/drivers/md/dm-log-writes.c b/drivers/md/dm-log-writes.c
index 99721c76225d..be20605f7544 100644
--- a/drivers/md/dm-log-writes.c
+++ b/drivers/md/dm-log-writes.c
@@ -994,10 +994,26 @@  static size_t log_writes_dax_copy_to_iter(struct dm_target *ti,
 	return dax_copy_to_iter(lc->dev->dax_dev, pgoff, addr, bytes, i);
 }
 
+static int log_writes_dax_zero_page_range(struct dm_target *ti,
+					  pgoff_t pgoff, unsigned offset,
+					  size_t len)
+{
+	int ret;
+	struct log_writes_c *lc = ti->private;
+	sector_t sector = pgoff * PAGE_SECTORS;
+
+	ret = bdev_dax_pgoff(lc->dev->bdev, sector, ALIGN(len, PAGE_SIZE),
+			     &pgoff);
+	if (ret)
+		return ret;
+	return dax_zero_page_range(lc->dev->dax_dev, pgoff, offset, len);
+}
+
 #else
 #define log_writes_dax_direct_access NULL
 #define log_writes_dax_copy_from_iter NULL
 #define log_writes_dax_copy_to_iter NULL
+#define log_writes_dax_zero_page_range NULL
 #endif
 
 static struct target_type log_writes_target = {
@@ -1016,6 +1032,7 @@  static struct target_type log_writes_target = {
 	.direct_access = log_writes_dax_direct_access,
 	.dax_copy_from_iter = log_writes_dax_copy_from_iter,
 	.dax_copy_to_iter = log_writes_dax_copy_to_iter,
+	.dax_zero_page_range = log_writes_dax_zero_page_range,
 };
 
 static int __init dm_log_writes_init(void)
diff --git a/drivers/md/dm-stripe.c b/drivers/md/dm-stripe.c
index 63bbcc20f49a..8ad3c956efbf 100644
--- a/drivers/md/dm-stripe.c
+++ b/drivers/md/dm-stripe.c
@@ -360,10 +360,32 @@  static size_t stripe_dax_copy_to_iter(struct dm_target *ti, pgoff_t pgoff,
 	return dax_copy_to_iter(dax_dev, pgoff, addr, bytes, i);
 }
 
+static int stripe_dax_zero_page_range(struct dm_target *ti, pgoff_t pgoff,
+				      unsigned offset, size_t len)
+{
+	int ret;
+	sector_t dev_sector, sector = pgoff * PAGE_SECTORS;
+	struct stripe_c *sc = ti->private;
+	struct dax_device *dax_dev;
+	struct block_device *bdev;
+	uint32_t stripe;
+
+	stripe_map_sector(sc, sector, &stripe, &dev_sector);
+	dev_sector += sc->stripe[stripe].physical_start;
+	dax_dev = sc->stripe[stripe].dev->dax_dev;
+	bdev = sc->stripe[stripe].dev->bdev;
+
+	ret = bdev_dax_pgoff(bdev, dev_sector, ALIGN(len, PAGE_SIZE), &pgoff);
+	if (ret)
+		return ret;
+	return dax_zero_page_range(dax_dev, pgoff, offset, len);
+}
+
 #else
 #define stripe_dax_direct_access NULL
 #define stripe_dax_copy_from_iter NULL
 #define stripe_dax_copy_to_iter NULL
+#define stripe_dax_zero_page_range NULL
 #endif
 
 /*
@@ -486,6 +508,7 @@  static struct target_type stripe_target = {
 	.direct_access = stripe_dax_direct_access,
 	.dax_copy_from_iter = stripe_dax_copy_from_iter,
 	.dax_copy_to_iter = stripe_dax_copy_to_iter,
+	.dax_zero_page_range = stripe_dax_zero_page_range,
 };
 
 int __init dm_stripe_init(void)
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index e8f9661a10a1..4605d30dad60 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1198,6 +1198,35 @@  static size_t dm_dax_copy_to_iter(struct dax_device *dax_dev, pgoff_t pgoff,
 	return ret;
 }
 
+static int dm_dax_zero_page_range(struct dax_device *dax_dev, pgoff_t pgoff,
+				  unsigned offset, size_t len)
+{
+	struct mapped_device *md = dax_get_private(dax_dev);
+	sector_t sector = pgoff * PAGE_SECTORS;
+	struct dm_target *ti;
+	int ret = -EIO;
+	int srcu_idx;
+
+	ti = dm_dax_get_live_target(md, sector, &srcu_idx);
+
+	if (!ti)
+		goto out;
+	if (WARN_ON(!ti->type->dax_zero_page_range)) {
+		/*
+		 * ->zero_page_range() is mandatory dax operation. If we are
+		 *  here, something is wrong.
+		 */
+		dm_put_live_table(md, srcu_idx);
+		goto out;
+	}
+	ret = ti->type->dax_zero_page_range(ti, pgoff, offset, len);
+
+ out:
+	dm_put_live_table(md, srcu_idx);
+
+	return ret;
+}
+
 /*
  * A target may call dm_accept_partial_bio only from the map routine.  It is
  * allowed for all bio types except REQ_PREFLUSH, REQ_OP_ZONE_RESET,
@@ -3194,6 +3223,7 @@  static const struct dax_operations dm_dax_ops = {
 	.dax_supported = dm_dax_supported,
 	.copy_from_iter = dm_dax_copy_from_iter,
 	.copy_to_iter = dm_dax_copy_to_iter,
+	.zero_page_range = dm_dax_zero_page_range,
 };
 
 /*
diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h
index 475668c69dbc..04009accf819 100644
--- a/include/linux/device-mapper.h
+++ b/include/linux/device-mapper.h
@@ -141,6 +141,8 @@  typedef long (*dm_dax_direct_access_fn) (struct dm_target *ti, pgoff_t pgoff,
 		long nr_pages, void **kaddr, pfn_t *pfn);
 typedef size_t (*dm_dax_copy_iter_fn)(struct dm_target *ti, pgoff_t pgoff,
 		void *addr, size_t bytes, struct iov_iter *i);
+typedef int (*dm_dax_zero_page_range_fn)(struct dm_target *ti, pgoff_t pgoff,
+		unsigned, size_t len);
 #define PAGE_SECTORS (PAGE_SIZE / 512)
 
 void dm_error(const char *message);
@@ -195,6 +197,7 @@  struct target_type {
 	dm_dax_direct_access_fn direct_access;
 	dm_dax_copy_iter_fn dax_copy_from_iter;
 	dm_dax_copy_iter_fn dax_copy_to_iter;
+	dm_dax_zero_page_range_fn dax_zero_page_range;
 
 	/* For internal device-mapper use. */
 	struct list_head list;