in UFS, each request is designated via the triplet <iid, lun, task tag>.
In UFS4.0 the Initiator ID field is 8 bits wide, comprised of the
EXT_IID and IID fields. Together with the task tag (single byte), they
limit the driver's hw queues capacity.
---
v1 -> v2:
Attend Johannes's and Bart's comments
Signed-off-by: Avri Altman <avri.altman@xxxxxxx>
---
drivers/ufs/core/ufshcd.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index 35a3bd95c5e4..cac7c9918c5b 100644
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -8468,6 +8468,11 @@ static int ufshcd_alloc_mcq(struct ufs_hba *hba)
if (ret)
goto err;
+ if (hba->nutrs * hba->nr_hw_queues > SZ_64K - 1) {
+ dev_info(hba->dev, "there can be at most 64K inflight requests\n");
+ goto err;
+ }
+
/*
* Previously allocated memory for nutrs may not be enough in MCQ mode.
* Number of supported tags in MCQ mode may be larger than SDB mode.
--
2.17.1
