[PATCH v2 3/6] powerpc/pseries/iommu: Move window-removing part of remove_ddw into remove_dma_window

From: Leonardo Bras
Date: Wed Jun 24 2020 - 02:24:44 EST


Move the window-removing part of remove_ddw into a new function
(remove_dma_window), so it can be used to remove other DMA windows.

It's useful for removing DMA windows that don't create DIRECT64_PROPNAME
property, like the default DMA window from the device, which uses
"ibm,dma-window".

Signed-off-by: Leonardo Bras <leobras.c@xxxxxxxxx>
---
arch/powerpc/platforms/pseries/iommu.c | 45 +++++++++++++++-----------
1 file changed, 27 insertions(+), 18 deletions(-)

diff --git a/arch/powerpc/platforms/pseries/iommu.c b/arch/powerpc/platforms/pseries/iommu.c
index 558e5441c355..a8840d9e1c35 100644
--- a/arch/powerpc/platforms/pseries/iommu.c
+++ b/arch/powerpc/platforms/pseries/iommu.c
@@ -776,25 +776,14 @@ static int __init disable_ddw_setup(char *str)

early_param("disable_ddw", disable_ddw_setup);

-static void remove_ddw(struct device_node *np, bool remove_prop)
+static void remove_dma_window(struct device_node *np, u32 *ddw_avail,
+ struct property *win)
{
struct dynamic_dma_window_prop *dwp;
- struct property *win64;
- u32 ddw_avail[DDW_APPLICABLE_SIZE];
u64 liobn;
- int ret = 0;
-
- ret = of_property_read_u32_array(np, "ibm,ddw-applicable",
- &ddw_avail[0], DDW_APPLICABLE_SIZE);
-
- win64 = of_find_property(np, DIRECT64_PROPNAME, NULL);
- if (!win64)
- return;
-
- if (ret || win64->length < sizeof(*dwp))
- goto delprop;
+ int ret;

- dwp = win64->value;
+ dwp = win->value;
liobn = (u64)be32_to_cpu(dwp->liobn);

/* clear the whole window, note the arg is in kernel pages */
@@ -816,10 +805,30 @@ static void remove_ddw(struct device_node *np, bool remove_prop)
pr_debug("%pOF: successfully removed direct window: rtas returned "
"%d to ibm,remove-pe-dma-window(%x) %llx\n",
np, ret, ddw_avail[DDW_REMOVE_PE_DMA_WIN], liobn);
+}
+
+static void remove_ddw(struct device_node *np, bool remove_prop)
+{
+ struct property *win;
+ u32 ddw_avail[DDW_APPLICABLE_SIZE];
+ int ret = 0;
+
+ ret = of_property_read_u32_array(np, "ibm,ddw-applicable",
+ &ddw_avail[0], DDW_APPLICABLE_SIZE);
+ if (ret)
+ return;
+
+ win = of_find_property(np, DIRECT64_PROPNAME, NULL);
+ if (!win)
+ return;
+
+ if (win->length >= sizeof(struct dynamic_dma_window_prop))
+ remove_dma_window(np, ddw_avail, win);
+
+ if (!remove_prop)
+ return;

-delprop:
- if (remove_prop)
- ret = of_remove_property(np, win64);
+ ret = of_remove_property(np, win);
if (ret)
pr_warn("%pOF: failed to remove direct window property: %d\n",
np, ret);
--
2.25.4