[PATCH v13 4/7] dm: enable synchronous dax

2019-06-21 Thread Pankaj Gupta
This patch sets dax device 'DAXDEV_SYNC' flag if all the target
devices of device mapper support synchrononous DAX. If device
mapper consists of both synchronous and asynchronous dax devices,
we don't set 'DAXDEV_SYNC' flag.

'dm_table_supports_dax' is refactored to pass 'iterate_devices_fn'
as argument so that the callers can pass the appropriate functions.

Suggested-by: Mike Snitzer 
Signed-off-by: Pankaj Gupta 
Reviewed-by: Mike Snitzer 
---
 drivers/md/dm-table.c | 24 ++--
 drivers/md/dm.c   |  2 +-
 drivers/md/dm.h   |  5 -
 3 files changed, 23 insertions(+), 8 deletions(-)

diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
index 350cf0451456..81c55304c4fa 100644
--- a/drivers/md/dm-table.c
+++ b/drivers/md/dm-table.c
@@ -881,7 +881,7 @@ void dm_table_set_type(struct dm_table *t, enum 
dm_queue_mode type)
 EXPORT_SYMBOL_GPL(dm_table_set_type);
 
 /* validate the dax capability of the target device span */
-static int device_supports_dax(struct dm_target *ti, struct dm_dev *dev,
+int device_supports_dax(struct dm_target *ti, struct dm_dev *dev,
   sector_t start, sector_t len, void *data)
 {
int blocksize = *(int *) data;
@@ -890,7 +890,15 @@ static int device_supports_dax(struct dm_target *ti, 
struct dm_dev *dev,
start, len);
 }
 
-bool dm_table_supports_dax(struct dm_table *t, int blocksize)
+/* Check devices support synchronous DAX */
+static int device_synchronous(struct dm_target *ti, struct dm_dev *dev,
+  sector_t start, sector_t len, void *data)
+{
+   return dax_synchronous(dev->dax_dev);
+}
+
+bool dm_table_supports_dax(struct dm_table *t,
+ iterate_devices_callout_fn iterate_fn, int *blocksize)
 {
struct dm_target *ti;
unsigned i;
@@ -903,8 +911,7 @@ bool dm_table_supports_dax(struct dm_table *t, int 
blocksize)
return false;
 
if (!ti->type->iterate_devices ||
-   !ti->type->iterate_devices(ti, device_supports_dax,
-   ))
+   !ti->type->iterate_devices(ti, iterate_fn, blocksize))
return false;
}
 
@@ -940,6 +947,7 @@ static int dm_table_determine_type(struct dm_table *t)
struct dm_target *tgt;
struct list_head *devices = dm_table_get_devices(t);
enum dm_queue_mode live_md_type = dm_get_md_type(t->md);
+   int page_size = PAGE_SIZE;
 
if (t->type != DM_TYPE_NONE) {
/* target already set the table's type */
@@ -984,7 +992,7 @@ static int dm_table_determine_type(struct dm_table *t)
 verify_bio_based:
/* We must use this table as bio-based */
t->type = DM_TYPE_BIO_BASED;
-   if (dm_table_supports_dax(t, PAGE_SIZE) ||
+   if (dm_table_supports_dax(t, device_supports_dax, _size) ||
(list_empty(devices) && live_md_type == 
DM_TYPE_DAX_BIO_BASED)) {
t->type = DM_TYPE_DAX_BIO_BASED;
} else {
@@ -1883,6 +1891,7 @@ void dm_table_set_restrictions(struct dm_table *t, struct 
request_queue *q,
   struct queue_limits *limits)
 {
bool wc = false, fua = false;
+   int page_size = PAGE_SIZE;
 
/*
 * Copy table's limits to the DM device's request_queue
@@ -1910,8 +1919,11 @@ 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(t, PAGE_SIZE))
+   if (dm_table_supports_dax(t, device_supports_dax, _size)) {
blk_queue_flag_set(QUEUE_FLAG_DAX, q);
+   if (dm_table_supports_dax(t, device_synchronous, NULL))
+   set_dax_synchronous(t->md->dax_dev);
+   }
else
blk_queue_flag_clear(QUEUE_FLAG_DAX, q);
 
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index b1caa7188209..b92c42a72ad4 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1119,7 +1119,7 @@ static bool dm_dax_supported(struct dax_device *dax_dev, 
struct block_device *bd
if (!map)
return false;
 
-   ret = dm_table_supports_dax(map, blocksize);
+   ret = dm_table_supports_dax(map, device_supports_dax, );
 
dm_put_live_table(md, srcu_idx);
 
diff --git a/drivers/md/dm.h b/drivers/md/dm.h
index 17e3db54404c..0475673337f3 100644
--- a/drivers/md/dm.h
+++ b/drivers/md/dm.h
@@ -72,7 +72,10 @@ bool dm_table_bio_based(struct dm_table *t);
 bool dm_table_request_based(struct dm_table *t);
 void dm_table_free_md_mempools(struct dm_table *t);
 struct dm_md_mempools *dm_table_get_md_mempools(struct dm_table *t);
-bool dm_table_supports_dax(struct dm_table *t, int blocksize);
+bool dm_table_supports_dax(struct dm_table *t, iterate_devices_callout_fn fn,
+  int *blocksize);
+int 

[PATCH v13 4/7] dm: enable synchronous dax

2019-06-12 Thread Pankaj Gupta
This patch sets dax device 'DAXDEV_SYNC' flag if all the target
devices of device mapper support synchrononous DAX. If device
mapper consists of both synchronous and asynchronous dax devices,
we don't set 'DAXDEV_SYNC' flag.

'dm_table_supports_dax' is refactored to pass 'iterate_devices_fn'
as argument so that the callers can pass the appropriate functions.

Suggested-by: Mike Snitzer 
Signed-off-by: Pankaj Gupta 
Reviewed-by: Mike Snitzer 
---
 drivers/md/dm-table.c | 24 ++--
 drivers/md/dm.c   |  2 +-
 drivers/md/dm.h   |  5 -
 3 files changed, 23 insertions(+), 8 deletions(-)

diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
index 350cf0451456..81c55304c4fa 100644
--- a/drivers/md/dm-table.c
+++ b/drivers/md/dm-table.c
@@ -881,7 +881,7 @@ void dm_table_set_type(struct dm_table *t, enum 
dm_queue_mode type)
 EXPORT_SYMBOL_GPL(dm_table_set_type);
 
 /* validate the dax capability of the target device span */
-static int device_supports_dax(struct dm_target *ti, struct dm_dev *dev,
+int device_supports_dax(struct dm_target *ti, struct dm_dev *dev,
   sector_t start, sector_t len, void *data)
 {
int blocksize = *(int *) data;
@@ -890,7 +890,15 @@ static int device_supports_dax(struct dm_target *ti, 
struct dm_dev *dev,
start, len);
 }
 
-bool dm_table_supports_dax(struct dm_table *t, int blocksize)
+/* Check devices support synchronous DAX */
+static int device_synchronous(struct dm_target *ti, struct dm_dev *dev,
+  sector_t start, sector_t len, void *data)
+{
+   return dax_synchronous(dev->dax_dev);
+}
+
+bool dm_table_supports_dax(struct dm_table *t,
+ iterate_devices_callout_fn iterate_fn, int *blocksize)
 {
struct dm_target *ti;
unsigned i;
@@ -903,8 +911,7 @@ bool dm_table_supports_dax(struct dm_table *t, int 
blocksize)
return false;
 
if (!ti->type->iterate_devices ||
-   !ti->type->iterate_devices(ti, device_supports_dax,
-   ))
+   !ti->type->iterate_devices(ti, iterate_fn, blocksize))
return false;
}
 
@@ -940,6 +947,7 @@ static int dm_table_determine_type(struct dm_table *t)
struct dm_target *tgt;
struct list_head *devices = dm_table_get_devices(t);
enum dm_queue_mode live_md_type = dm_get_md_type(t->md);
+   int page_size = PAGE_SIZE;
 
if (t->type != DM_TYPE_NONE) {
/* target already set the table's type */
@@ -984,7 +992,7 @@ static int dm_table_determine_type(struct dm_table *t)
 verify_bio_based:
/* We must use this table as bio-based */
t->type = DM_TYPE_BIO_BASED;
-   if (dm_table_supports_dax(t, PAGE_SIZE) ||
+   if (dm_table_supports_dax(t, device_supports_dax, _size) ||
(list_empty(devices) && live_md_type == 
DM_TYPE_DAX_BIO_BASED)) {
t->type = DM_TYPE_DAX_BIO_BASED;
} else {
@@ -1883,6 +1891,7 @@ void dm_table_set_restrictions(struct dm_table *t, struct 
request_queue *q,
   struct queue_limits *limits)
 {
bool wc = false, fua = false;
+   int page_size = PAGE_SIZE;
 
/*
 * Copy table's limits to the DM device's request_queue
@@ -1910,8 +1919,11 @@ 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(t, PAGE_SIZE))
+   if (dm_table_supports_dax(t, device_supports_dax, _size)) {
blk_queue_flag_set(QUEUE_FLAG_DAX, q);
+   if (dm_table_supports_dax(t, device_synchronous, NULL))
+   set_dax_synchronous(t->md->dax_dev);
+   }
else
blk_queue_flag_clear(QUEUE_FLAG_DAX, q);
 
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index b1caa7188209..b92c42a72ad4 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1119,7 +1119,7 @@ static bool dm_dax_supported(struct dax_device *dax_dev, 
struct block_device *bd
if (!map)
return false;
 
-   ret = dm_table_supports_dax(map, blocksize);
+   ret = dm_table_supports_dax(map, device_supports_dax, );
 
dm_put_live_table(md, srcu_idx);
 
diff --git a/drivers/md/dm.h b/drivers/md/dm.h
index 17e3db54404c..0475673337f3 100644
--- a/drivers/md/dm.h
+++ b/drivers/md/dm.h
@@ -72,7 +72,10 @@ bool dm_table_bio_based(struct dm_table *t);
 bool dm_table_request_based(struct dm_table *t);
 void dm_table_free_md_mempools(struct dm_table *t);
 struct dm_md_mempools *dm_table_get_md_mempools(struct dm_table *t);
-bool dm_table_supports_dax(struct dm_table *t, int blocksize);
+bool dm_table_supports_dax(struct dm_table *t, iterate_devices_callout_fn fn,
+  int *blocksize);
+int