If one of the MD raid participating target dax device supports DAXDEV_RECOVERY, then it'll be declared on the whole that the MD device is capable of DAXDEV_RECOVERY. And only when the recovery process reaches to the target driver, it becomes deterministic whether a certain dax address range maybe recovered, or not. Signed-off-by: Jane Chu <jane.chu@xxxxxxxxxx> --- drivers/md/dm-table.c | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c index e43096cfe9e2..8af8a81b6172 100644 --- a/drivers/md/dm-table.c +++ b/drivers/md/dm-table.c @@ -844,6 +844,36 @@ static bool dm_table_supports_dax(struct dm_table *t, return true; } +/* Check whether device is capable of dax poison recovery */ +static int device_poison_recovery_capable(struct dm_target *ti, + struct dm_dev *dev, sector_t start, sector_t len, void *data) +{ + if (!dev->dax_dev) + return false; + return dax_recovery_capable(dev->dax_dev); +} + +static bool dm_table_supports_poison_recovery(struct dm_table *t, + iterate_devices_callout_fn func) +{ + struct dm_target *ti; + unsigned int i; + + /* Check if any DAX target supports poison recovery */ + for (i = 0; i < dm_table_get_num_targets(t); i++) { + ti = dm_table_get_target(t, i); + + if (!ti->type->direct_access) + return false; + + if (ti->type->iterate_devices && + ti->type->iterate_devices(ti, func, NULL)) + return true; + } + + return false; +} + static int device_is_rq_stackable(struct dm_target *ti, struct dm_dev *dev, sector_t start, sector_t len, void *data) { @@ -2014,6 +2044,9 @@ int dm_table_set_restrictions(struct dm_table *t, struct request_queue *q, blk_queue_flag_set(QUEUE_FLAG_DAX, q); if (dm_table_supports_dax(t, device_not_dax_synchronous_capable)) set_dax_synchronous(t->md->dax_dev); + if (dm_table_supports_poison_recovery(t, + device_poison_recovery_capable)) + set_dax_recovery(t->md->dax_dev); } else blk_queue_flag_clear(QUEUE_FLAG_DAX, q); -- 2.18.4