[PATCH v2 3/3] lib/logic_iomem: fix operation on 32-bit
Johannes Berg
johannes at sipsolutions.net
Wed Sep 15 11:30:22 PDT 2021
From: Johannes Berg <johannes.berg at intel.com>
On 32-bit, the first entry might be at 0/NULL, but that's
strange and leads to issues, e.g. where we check "if (ret)".
Use a IOREMAP_BIAS/IOREMAP_MASK of 0x80000000UL to avoid
this. This then requires reducing the number of areas (via
MAX_AREAS), but we still have 128 areas, which is enough.
Fixes: ca2e334232b6 ("lib: add iomem emulation (logic_iomem)")
Signed-off-by: Johannes Berg <johannes.berg at intel.com>
---
lib/logic_iomem.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/lib/logic_iomem.c b/lib/logic_iomem.c
index 54fa601f3300..549b22d4bcde 100644
--- a/lib/logic_iomem.c
+++ b/lib/logic_iomem.c
@@ -21,15 +21,15 @@ struct logic_iomem_area {
#define AREA_SHIFT 24
#define MAX_AREA_SIZE (1 << AREA_SHIFT)
-#define MAX_AREAS ((1ULL<<32) / MAX_AREA_SIZE)
+#define MAX_AREAS ((1U << 31) / MAX_AREA_SIZE)
#define AREA_BITS ((MAX_AREAS - 1) << AREA_SHIFT)
#define AREA_MASK (MAX_AREA_SIZE - 1)
#ifdef CONFIG_64BIT
#define IOREMAP_BIAS 0xDEAD000000000000UL
#define IOREMAP_MASK 0xFFFFFFFF00000000UL
#else
-#define IOREMAP_BIAS 0
-#define IOREMAP_MASK 0
+#define IOREMAP_BIAS 0x80000000UL
+#define IOREMAP_MASK 0x80000000UL
#endif
static DEFINE_MUTEX(regions_mtx);
--
2.31.1
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