Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 273752c9 authored by Vivek Goyal's avatar Vivek Goyal Committed by Mike Snitzer
Browse files

dm, dax: Make sure dm_dax_flush() is called if device supports it 



Currently dm_dax_flush() is not being called, even if underlying dax
device supports write cache, because DAXDEV_WRITE_CACHE is not being
propagated up to the DM dax device.

If the underlying dax device supports write cache, set
DAXDEV_WRITE_CACHE on the DM dax device.  This will cause dm_dax_flush()
to be called.

Fixes: abebfbe2 ("dm: add ->flush() dax operation support")
Signed-off-by: default avatarVivek Goyal <vgoyal@redhat.com>
Acked-by: default avatarDan Williams <dan.j.williams@intel.com>
Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
parent 34c96507

drivers/dax/super.c

+6 −0
Original line number Diff line number Diff line
@@ -278,6 +278,12 @@ void dax_write_cache(struct dax_device *dax_dev, bool wc) 
}

EXPORT_SYMBOL_GPL(dax_write_cache);



bool dax_write_cache_enabled(struct dax_device *dax_dev)

{

	return test_bit(DAXDEV_WRITE_CACHE, &dax_dev->flags);

}

EXPORT_SYMBOL_GPL(dax_write_cache_enabled);



bool dax_alive(struct dax_device *dax_dev)

{

	lockdep_assert_held(&dax_srcu);

drivers/md/dm-table.c

+35 −0
Original line number Diff line number Diff line
@@ -20,6 +20,7 @@ 
#include <linux/atomic.h>

#include <linux/blk-mq.h>

#include <linux/mount.h>

#include <linux/dax.h>



#define DM_MSG_PREFIX "table"
@@ -1630,6 +1631,37 @@ static bool dm_table_supports_flush(struct dm_table *t, unsigned long flush) 
	return false;

}



static int device_dax_write_cache_enabled(struct dm_target *ti,

					  struct dm_dev *dev, sector_t start,

					  sector_t len, void *data)

{

	struct dax_device *dax_dev = dev->dax_dev;



	if (!dax_dev)

		return false;



	if (dax_write_cache_enabled(dax_dev))

		return true;

	return false;

}



static int dm_table_supports_dax_write_cache(struct dm_table *t)

{

	struct dm_target *ti;

	unsigned i;



	for (i = 0; i < dm_table_get_num_targets(t); i++) {

		ti = dm_table_get_target(t, i);



		if (ti->type->iterate_devices &&

		    ti->type->iterate_devices(ti,

				device_dax_write_cache_enabled, NULL))

			return true;

	}



	return false;

}



static int device_is_nonrot(struct dm_target *ti, struct dm_dev *dev,

			    sector_t start, sector_t len, void *data)

{
@@ -1785,6 +1817,9 @@ void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q, 
	}

	blk_queue_write_cache(q, wc, fua);



	if (dm_table_supports_dax_write_cache(t))

		dax_write_cache(t->md->dax_dev, true);



	/* Ensure that all underlying devices are non-rotational. */

	if (dm_table_all_devices_attribute(t, device_is_nonrot))

		queue_flag_set_unlocked(QUEUE_FLAG_NONROT, q);

include/linux/dax.h

+1 −0
Original line number Diff line number Diff line
@@ -87,6 +87,7 @@ size_t dax_copy_from_iter(struct dax_device *dax_dev, pgoff_t pgoff, void *addr, 
void dax_flush(struct dax_device *dax_dev, pgoff_t pgoff, void *addr,

		size_t size);

void dax_write_cache(struct dax_device *dax_dev, bool wc);

bool dax_write_cache_enabled(struct dax_device *dax_dev);



/*

 * We use lowest available bit in exceptional entry for locking, one bit for