Change dm-flakey to implement direct_access function,
flakey_direct_access(), which maps sector and calls direct_access
function of its physical target device. This pretty much is a copy
from DM Linear.
This allows fs with DAX to pass in xfstests. It does not actually introduce
data corruption and dropping writes unlike the non-DAX path. The main
reason is due to the I/O path being out of dmflakey's control once
direct_access() has been called. The the existing implementation cannot
be adapted to DAX I/O path. The error injection will be introduced at a
later date with more thought.
Signed-off-by: Dave Jiang <dave.jiang@xxxxxxxxx>
---
drivers/md/dm-flakey.c | 21 ++++++++++++++++++++-
1 file changed, 20 insertions(+), 1 deletion(-)
diff --git a/drivers/md/dm-flakey.c b/drivers/md/dm-flakey.c
index 6a2e8dd..cf182a7 100644
--- a/drivers/md/dm-flakey.c
+++ b/drivers/md/dm-flakey.c
@@ -408,9 +408,27 @@ static int flakey_iterate_devices(struct dm_target *ti, iterate_devices_callout_
return fn(ti, fc->dev, fc->start, ti->len, data);
}
+static long flakey_direct_access(struct dm_target *ti, sector_t sector,
+ void **kaddr, pfn_t *pfn, long size)
+{
+ struct flakey_c *fc = ti->private;
+ struct block_device *bdev = fc->dev->bdev;
+ struct blk_dax_ctl dax = {
+ .sector = flakey_map_sector(ti, sector),
+ .size = size,
+ };
+ long ret;
+
+ ret = bdev_direct_access(bdev, &dax);
+ *kaddr = dax.addr;
+ *pfn = dax.pfn;
+
+ return ret;
+}
+
static struct target_type flakey_target = {
.name = "flakey",
- .version = {1, 3, 1},
+ .version = {1, 4, 0},
.module = THIS_MODULE,
.ctr = flakey_ctr,
.dtr = flakey_dtr,
@@ -419,6 +437,7 @@ static struct target_type flakey_target = {
.status = flakey_status,
.prepare_ioctl = flakey_prepare_ioctl,
.iterate_devices = flakey_iterate_devices,
+ .direct_access = flakey_direct_access,
};
static int __init dm_flakey_init(void)
--
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