[PATCH v2 02/18] powerpc/vas: Validate window credits

From: Sukadev Bhattiprolu
Date: Fri Oct 06 2017 - 22:32:51 EST


NX-842, the only user of VAS, sets the window credits to default values
but VAS should check the credits against the possible max values.

The VAS_WCREDS_MIN is not needed and can be dropped.

Signed-off-by: Sukadev Bhattiprolu <sukadev@xxxxxxxxxxxxxxxxxx>
---
arch/powerpc/platforms/powernv/vas-window.c | 6 ++++++
arch/powerpc/platforms/powernv/vas.h | 4 ++--
2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/platforms/powernv/vas-window.c b/arch/powerpc/platforms/powernv/vas-window.c
index cec7ab7..a2fe120 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -738,6 +738,9 @@ static bool rx_win_args_valid(enum vas_cop_type cop,
if (attr->rx_fifo_size > VAS_RX_FIFO_SIZE_MAX)
return false;

+ if (attr->wcreds_max > VAS_RX_WCREDS_MAX)
+ return false;
+
if (attr->nx_win) {
/* cannot be fault or user window if it is nx */
if (attr->fault_win || attr->user_win)
@@ -927,6 +930,9 @@ static bool tx_win_args_valid(enum vas_cop_type cop,
if (cop > VAS_COP_TYPE_MAX)
return false;

+ if (attr->wcreds_max > VAS_TX_WCREDS_MAX)
+ return false;
+
if (attr->user_win &&
(cop != VAS_COP_TYPE_FTW || attr->rsvd_txbuf_count))
return false;
diff --git a/arch/powerpc/platforms/powernv/vas.h b/arch/powerpc/platforms/powernv/vas.h
index 38dee5d..fea0de4 100644
--- a/arch/powerpc/platforms/powernv/vas.h
+++ b/arch/powerpc/platforms/powernv/vas.h
@@ -106,8 +106,8 @@
*
* TODO: Needs tuning for per-process credits
*/
-#define VAS_WCREDS_MIN 16
-#define VAS_WCREDS_MAX ((64 << 10) - 1)
+#define VAS_RX_WCREDS_MAX ((64 << 10) - 1)
+#define VAS_TX_WCREDS_MAX ((4 << 10) - 1)
#define VAS_WCREDS_DEFAULT (1 << 10)

/*
--
2.7.4