From: Joerg Roedel <jroedel@suse.de>
Date: Thu, 10 Jun 2021 08:31:20 +0000 (+0200)
Subject: iommu/vt-d: Fix linker error on 32-bit
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=d6a9642bd673dd0bb2839274fe83eaa979b9207e;p=linux.git

iommu/vt-d: Fix linker error on 32-bit

A recent commit broke the build on 32-bit x86. The linker throws these
messages:

	ld: drivers/iommu/intel/perf.o: in function `dmar_latency_snapshot':
	perf.c:(.text+0x40c): undefined reference to `__udivdi3'
	ld: perf.c:(.text+0x458): undefined reference to `__udivdi3'

The reason are the 64-bit divides in dmar_latency_snapshot(). Use the
div_u64() helper function for those.

Fixes: 55ee5e67a59a ("iommu/vt-d: Add common code for dmar latency performance monitors")
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Link: https://lore.kernel.org/r/20210610083120.29224-1-joro@8bytes.org
---

diff --git a/drivers/iommu/intel/perf.c b/drivers/iommu/intel/perf.c
index faaa96dda4377..73b7ec7055521 100644
--- a/drivers/iommu/intel/perf.c
+++ b/drivers/iommu/intel/perf.c
@@ -141,14 +141,14 @@ int dmar_latency_snapshot(struct intel_iommu *iommu, char *str, size_t size)
 				if (val == UINT_MAX)
 					val = 0;
 				else
-					val /= 1000;
+					val = div_u64(val, 1000);
 				break;
 			case COUNTS_MAX:
-				val /= 1000;
+				val = div_u64(val, 1000);
 				break;
 			case COUNTS_SUM:
 				if (lstat[i].samples)
-					val /= (lstat[i].samples * 1000);
+					val = div_u64(val, (lstat[i].samples * 1000));
 				else
 					val = 0;
 				break;