From 92fe01b7c655b9767724e7d62bdded0761d232ff Mon Sep 17 00:00:00 2001
From: Alexey Kardashevskiy <aik@ozlabs.ru>
Date: Thu, 21 Oct 2021 00:23:14 +1100
Subject: [PATCH] powerpc/pseries/iommu: Check if the default window in use
before removing it
References: bsc#1212091 ltc#199106
Patch-mainline: v5.15
Git-commit: 92fe01b7c655b9767724e7d62bdded0761d232ff
At the moment this check is performed after we remove the default window
which is late and disallows to revert whatever changes enable_ddw()
has made to DMA windows.
This moves the check and error exit before removing the window.
This raised the message severity from "debug" to "warning" as this
should not happen in practice and cannot be triggered by the userspace.
Fixes: 381ceda88c4c ("powerpc/pseries/iommu: Make use of DDW for indirect mapping")
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211020132315.2287178-4-aik@ozlabs.ru
Acked-by: Michal Suchanek <msuchanek@suse.de>
---
arch/powerpc/platforms/pseries/iommu.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/arch/powerpc/platforms/pseries/iommu.c b/arch/powerpc/platforms/pseries/iommu.c
index c003f698eedd..8f921e38ce74 100644
--- a/arch/powerpc/platforms/pseries/iommu.c
+++ b/arch/powerpc/platforms/pseries/iommu.c
@@ -1302,6 +1302,12 @@ static bool enable_ddw(struct pci_dev *dev, struct device_node *pdn)
struct property *default_win;
int reset_win_ext;
+ /* DDW + IOMMU on single window may fail if there is any allocation */
+ if (iommu_table_in_use(tbl)) {
+ dev_warn(&dev->dev, "current IOMMU table in use, can't be replaced.\n");
+ goto out_failed;
+ }
+
default_win = of_find_property(pdn, "ibm,dma-window", NULL);
if (!default_win)
goto out_failed;
@@ -1356,12 +1362,6 @@ static bool enable_ddw(struct pci_dev *dev, struct device_node *pdn)
query.largest_available_block,
1ULL << page_shift);
- /* DDW + IOMMU on single window may fail if there is any allocation */
- if (default_win_removed && iommu_table_in_use(tbl)) {
- dev_dbg(&dev->dev, "current IOMMU table in use, can't be replaced.\n");
- goto out_failed;
- }
-
len = order_base_2(query.largest_available_block << page_shift);
win_name = DMA64_PROPNAME;
} else {
--
2.41.0