| Message ID | 20190514145422.16923-5-pagupta@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | virtio pmem driver | expand |
[ add Mike and dm-devel ] Mike, any concerns with the below addition to the device-mapper-dax implementation? On Tue, May 14, 2019 at 7:58 AM Pankaj Gupta <pagupta@redhat.com> wrote: > > 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. > > Signed-off-by: Pankaj Gupta <pagupta@redhat.com> > --- > drivers/md/dm-table.c | 14 ++++++++++++++ > 1 file changed, 14 insertions(+) > > diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c > index cde3b49b2a91..1cce626ff576 100644 > --- a/drivers/md/dm-table.c > +++ b/drivers/md/dm-table.c > @@ -886,10 +886,17 @@ static int device_supports_dax(struct dm_target *ti, struct dm_dev *dev, > return bdev_dax_supported(dev->bdev, PAGE_SIZE); > } > > +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); > +} > + > static bool dm_table_supports_dax(struct dm_table *t) > { > struct dm_target *ti; > unsigned i; > + bool dax_sync = true; > > /* Ensure that all targets support DAX. */ > for (i = 0; i < dm_table_get_num_targets(t); i++) { > @@ -901,7 +908,14 @@ static bool dm_table_supports_dax(struct dm_table *t) > if (!ti->type->iterate_devices || > !ti->type->iterate_devices(ti, device_supports_dax, NULL)) > return false; > + > + /* Check devices support synchronous DAX */ > + if (dax_sync && > + !ti->type->iterate_devices(ti, device_synchronous, NULL)) > + dax_sync = false; > } > + if (dax_sync) > + set_dax_synchronous(t->md->dax_dev); > > return true; > } > -- > 2.20.1 >
diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c index cde3b49b2a91..1cce626ff576 100644 --- a/drivers/md/dm-table.c +++ b/drivers/md/dm-table.c @@ -886,10 +886,17 @@ static int device_supports_dax(struct dm_target *ti, struct dm_dev *dev, return bdev_dax_supported(dev->bdev, PAGE_SIZE); } +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); +} + static bool dm_table_supports_dax(struct dm_table *t) { struct dm_target *ti; unsigned i; + bool dax_sync = true; /* Ensure that all targets support DAX. */ for (i = 0; i < dm_table_get_num_targets(t); i++) { @@ -901,7 +908,14 @@ static bool dm_table_supports_dax(struct dm_table *t) if (!ti->type->iterate_devices || !ti->type->iterate_devices(ti, device_supports_dax, NULL)) return false; + + /* Check devices support synchronous DAX */ + if (dax_sync && + !ti->type->iterate_devices(ti, device_synchronous, NULL)) + dax_sync = false; } + if (dax_sync) + set_dax_synchronous(t->md->dax_dev); return true; }
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. Signed-off-by: Pankaj Gupta <pagupta@redhat.com> --- drivers/md/dm-table.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+)