[PATCH 5/6] dm, dm-linear: Add dax_supported to dm_target
From: Toshi Kani <hidden>
Date: 2016-06-13 22:31:59
Also in:
dm-devel, lkml, nvdimm
Subsystem:
device-mapper (lvm), the rest · Maintainers:
Alasdair Kergon, Mike Snitzer, Mikulas Patocka, Benjamin Marzinski, Linus Torvalds
Extend 'struct dm_target' to have dax_supported bit, which allows dm-table to check if a dm-target supports DAX. Change dm-linear to set this bit when its target physical device supports DAX. Signed-off-by: Toshi Kani <redacted> Cc: Alasdair Kergon <agk@redhat.com> Cc: Mike Snitzer <redacted> Cc: Dan Williams <redacted> Cc: Ross Zwisler <redacted> --- drivers/md/dm-linear.c | 2 ++ include/linux/device-mapper.h | 5 +++++ 2 files changed, 7 insertions(+)
diff --git a/drivers/md/dm-linear.c b/drivers/md/dm-linear.c
index 49bd7d2..6fdbbc8 100644
--- a/drivers/md/dm-linear.c
+++ b/drivers/md/dm-linear.c@@ -59,6 +59,8 @@ static int linear_ctr(struct dm_target *ti, unsigned int argc, char **argv) ti->num_flush_bios = 1; ti->num_discard_bios = 1; ti->num_write_same_bios = 1; + if (lc->dev->bdev->bd_disk->flags & GENHD_FL_DAX) + ti->dax_supported = 1; ti->private = lc; return 0;
diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h
index 16e6c8c..9b72989 100644
--- a/include/linux/device-mapper.h
+++ b/include/linux/device-mapper.h@@ -290,6 +290,11 @@ struct dm_target { * Set if this target does not return zeroes on discarded blocks. */ bool discard_zeroes_data_unsupported:1; + + /* + * Set if the target supports DAX (direct access). + */ + bool dax_supported:1; }; /* Each target can link one of these into the table */