This patch adds 'DAXDEV_SYNC' flag which is set
for nd_region doing synchronous flush. This later
is used to disable MAP_SYNC functionality for
ext4 & xfs filesystem for devices don't support
synchronous flush.
Signed-off-by: Pankaj Gupta <pagupta@xxxxxxxxxx>
---
drivers/dax/bus.c | 2 +-
drivers/dax/super.c | 13 ++++++++++++-
drivers/md/dm.c | 3 ++-
drivers/nvdimm/pmem.c | 3 ++-
drivers/nvdimm/region_devs.c | 7 +++++++
include/linux/dax.h | 8 ++++++--
include/linux/libnvdimm.h | 1 +
7 files changed, 31 insertions(+), 6 deletions(-)
diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c
index 2109cfe80219..5f184e751c82 100644
--- a/drivers/dax/bus.c
+++ b/drivers/dax/bus.c
@@ -388,7 +388,7 @@ struct dev_dax *__devm_create_dev_dax(struct dax_region *dax_region, int id,
* No 'host' or dax_operations since there is no access to this
* device outside of mmap of the resulting character device.
*/
- dax_dev = alloc_dax(dev_dax, NULL, NULL);
+ dax_dev = alloc_dax(dev_dax, NULL, NULL, DAXDEV_F_SYNC);
if (!dax_dev)
goto err;
diff --git a/drivers/dax/super.c b/drivers/dax/super.c
index 0a339b85133e..bd6509308d05 100644
--- a/drivers/dax/super.c
+++ b/drivers/dax/super.c
@@ -186,6 +186,8 @@ enum dax_device_flags {
DAXDEV_ALIVE,
/* gate whether dax_flush() calls the low level flush routine */
DAXDEV_WRITE_CACHE,
+ /* flag to check if device supports synchronous flush */
+ DAXDEV_SYNC,
};
/**
@@ -354,6 +356,12 @@ bool dax_write_cache_enabled(struct dax_device *dax_dev)
}
EXPORT_SYMBOL_GPL(dax_write_cache_enabled);
+bool dax_synchronous(struct dax_device *dax_dev)
+{
+ return test_bit(DAXDEV_SYNC, &dax_dev->flags);
+}
+EXPORT_SYMBOL_GPL(dax_synchronous);
+
bool dax_alive(struct dax_device *dax_dev)
{
lockdep_assert_held(&dax_srcu);
@@ -511,7 +519,7 @@ static void dax_add_host(struct dax_device *dax_dev, const char *host)
}
struct dax_device *alloc_dax(void *private, const char *__host,
- const struct dax_operations *ops)
+ const struct dax_operations *ops, bool sync)
{
struct dax_device *dax_dev;
const char *host;
@@ -534,6 +542,9 @@ struct dax_device *alloc_dax(void *private, const char *__host,
dax_add_host(dax_dev, host);
dax_dev->ops = ops;
dax_dev->private = private;
+ if (sync)
+ set_bit(DAXDEV_SYNC, &dax_dev->flags);
+
return dax_dev;
err_dev:
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 68d24056d0b1..dd5266fb5471 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1965,7 +1965,8 @@ static struct mapped_device *alloc_dev(int minor)
sprintf(md->disk->disk_name, "dm-%d", minor);
if (IS_ENABLED(CONFIG_DAX_DRIVER)) {
- dax_dev = alloc_dax(md, md->disk->disk_name, &dm_dax_ops);
+ dax_dev = alloc_dax(md, md->disk->disk_name, &dm_dax_ops,
+ DAXDEV_F_SYNC);
if (!dax_dev)
goto bad;
}
diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c
index f719245da170..34fa20381c05 100644
--- a/drivers/nvdimm/pmem.c
+++ b/drivers/nvdimm/pmem.c
@@ -466,7 +466,8 @@ static int pmem_attach_disk(struct device *dev,
nvdimm_badblocks_populate(nd_region, &pmem->bb, &bb_res);
disk->bb = &pmem->bb;
- dax_dev = alloc_dax(pmem, disk->disk_name, &pmem_dax_ops);
+ dax_dev = alloc_dax(pmem, disk->disk_name, &pmem_dax_ops,
+ is_nvdimm_sync(nd_region));
if (!dax_dev) {
put_disk(disk);
return -ENOMEM;
diff --git a/drivers/nvdimm/region_devs.c b/drivers/nvdimm/region_devs.c
index e5b59708865e..427cf28380c6 100644
--- a/drivers/nvdimm/region_devs.c
+++ b/drivers/nvdimm/region_devs.c
@@ -1219,6 +1219,13 @@ int nvdimm_has_cache(struct nd_region *nd_region)
}
EXPORT_SYMBOL_GPL(nvdimm_has_cache);
+bool is_nvdimm_sync(struct nd_region *nd_region)
+{
+ return is_nd_pmem(&nd_region->dev) &&
+ !test_bit(ND_REGION_ASYNC, &nd_region->flags);
+}
+EXPORT_SYMBOL_GPL(is_nvdimm_sync);
+
struct conflict_context {
struct nd_region *nd_region;
resource_size_t start, size;
diff --git a/include/linux/dax.h b/include/linux/dax.h
index 0dd316a74a29..c97fc0cc7167 100644
--- a/include/linux/dax.h
+++ b/include/linux/dax.h
@@ -7,6 +7,9 @@
#include <linux/radix-tree.h>
#include <asm/pgtable.h>
+/* Flag for synchronous flush */
+#define DAXDEV_F_SYNC true
+
typedef unsigned long dax_entry_t;
struct iomap_ops;
@@ -32,18 +35,19 @@ extern struct attribute_group dax_attribute_group;
#if IS_ENABLED(CONFIG_DAX)
struct dax_device *dax_get_by_host(const char *host);
struct dax_device *alloc_dax(void *private, const char *host,
- const struct dax_operations *ops);
+ const struct dax_operations *ops, bool sync);
void put_dax(struct dax_device *dax_dev);
void kill_dax(struct dax_device *dax_dev);
void dax_write_cache(struct dax_device *dax_dev, bool wc);
bool dax_write_cache_enabled(struct dax_device *dax_dev);
+bool dax_synchronous(struct dax_device *dax_dev);
#else
static inline struct dax_device *dax_get_by_host(const char *host)
{
return NULL;
}
static inline struct dax_device *alloc_dax(void *private, const char *host,
- const struct dax_operations *ops)
+ const struct dax_operations *ops, bool sync)
{
/*
* Callers should check IS_ENABLED(CONFIG_DAX) to know if this
diff --git a/include/linux/libnvdimm.h b/include/linux/libnvdimm.h
index a5f369ec3726..8ae6b65d67e2 100644
--- a/include/linux/libnvdimm.h
+++ b/include/linux/libnvdimm.h
@@ -270,6 +270,7 @@ 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);
+bool is_nvdimm_sync(struct nd_region *nd_region);
static inline int nvdimm_ctl(struct nvdimm *nvdimm, unsigned int cmd, void *buf,
unsigned int buf_len, int *cmd_rc)
--
2.20.1
