+ ia64-simplify-code-flow-around-swiotlb-init.patch added to -mm tree

+ ia64-simplify-code-flow-around-swiotlb-init.patch added to -mm tree

[akpm]

The patch titled
     Subject: ia64: simplify code flow around swiotlb init
has been added to the -mm tree.  Its filename is
     ia64-simplify-code-flow-around-swiotlb-init.patch

This patch should soon appear at
    https://ozlabs.org/~akpm/mmots/broken-out/ia64-simplify-code-flow-around-swiotlb-init.patch
and later at
    https://ozlabs.org/~akpm/mmotm/broken-out/ia64-simplify-code-flow-around-swiotlb-init.patch

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------------------------------------------------------
From: Sergei Trofimovich <slyfox@gentoo.org>
Subject: ia64: simplify code flow around swiotlb init

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.

Link: https://lkml.kernel.org/r/20210328202439.403601-1-slyfox@gentoo.org
Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

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

--- a/arch/ia64/mm/init.c~ia64-simplify-code-flow-around-swiotlb-init
+++ a/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);
_

Patches currently in -mm which might be from slyfox@gentoo.org are

ia64-drop-unused-ia64_fw_emu-ifdef.patch
ia64-simplify-code-flow-around-swiotlb-init.patch