[PATCH v4 1/6] btt: fix a missed NVDIMM_IO_ATOMIC case in the write path

Vishal Verma
2017-07-26T23:37:43Z

The IO context conversion for rw_bytes missed a case in the BTT write
path (btt_map_write) which should've been marked as atomic.

In reality this should not cause a problem, because map writes are to
small for nsio_rw_bytes to attempt error clearing, but it should be
fixed for posterity.

Add a might_sleep() in the non-atomic section of nsio_rw_bytes so that
things like the nfit unit tests, which don't actually sleep, can catch
bugs like this.

Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
---
drivers/nvdimm/btt.c | 3 ++-
drivers/nvdimm/claim.c | 1 +
2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/nvdimm/btt.c b/drivers/nvdimm/btt.c
index 14323fa..f6ea82f 100644
--- a/drivers/nvdimm/btt.c
+++ b/drivers/nvdimm/btt.c
@@ -1156,7 +1156,8 @@ static int btt_write_pg(struct btt *btt, struct bio_integrity_payload *bip,
if (ret)
goto out_map;

- ret = btt_map_write(arena, premap, new_postmap, 0, 0, 0);
+ ret = btt_map_write(arena, premap, new_postmap, 0, 0,
+ NVDIMM_IO_ATOMIC);
if (ret)
goto out_map;

diff --git a/drivers/nvdimm/claim.c b/drivers/nvdimm/claim.c
index 4777046..3e6404f 100644
--- a/drivers/nvdimm/claim.c
+++ b/drivers/nvdimm/claim.c
@@ -292,6 +292,7 @@ static int nsio_rw_bytes(struct nd_namespace_common *ndns,
&& !(flags & NVDIMM_IO_ATOMIC)) {
long cleared;

+ might_sleep();
cleared = nvdimm_clear_poison(&ndns->dev,
nsio->res.start + offset, size);
if (cleared < size)
--
2.9.3