[PATCH v2] ia64: simplify code flow around swiotlb init

From: Sergei Trofimovich
Date: Sun Mar 28 2021 - 16:25:36 EST


Before the change CONFIG_INTEL_IOMMU && !CONFIG_SWIOTLB && !CONFIG_FLATMEM
could skip `set_max_mapnr(max_low_pfn);` if iommu is not present on system.

CC: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
CC: John Paul Adrian Glaubitz <glaubitz@xxxxxxxxxxxxxxxxxxx>
CC: linux-ia64@xxxxxxxxxxxxxxx
Signed-off-by: Sergei Trofimovich <slyfox@xxxxxxxxxx>
---
Change since v1: fixed a typo in commit mesage.

arch/ia64/mm/init.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/arch/ia64/mm/init.c b/arch/ia64/mm/init.c
index 16d0d7d22657..a63585db94fe 100644
--- a/arch/ia64/mm/init.c
+++ b/arch/ia64/mm/init.c
@@ -644,13 +644,16 @@ mem_init (void)
* _before_ any drivers that may need the PCI DMA interface are
* initialized or bootmem has been freed.
*/
+ do {
#ifdef CONFIG_INTEL_IOMMU
- detect_intel_iommu();
- if (!iommu_detected)
+ detect_intel_iommu();
+ if (iommu_detected)
+ break;
#endif
#ifdef CONFIG_SWIOTLB
swiotlb_init(1);
#endif
+ } while (0);

#ifdef CONFIG_FLATMEM
BUG_ON(!mem_map);
--
2.31.1