[PATCH 06/11] x86/dma: Get rid of iommu_pass_through

Joerg Roedel
2019-08-19T13:22:51Z

This variable has no users anymore. Remove it and tell the
IOMMU code via its new functions about requested DMA modes.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
---
arch/x86/include/asm/iommu.h | 1 -
arch/x86/kernel/pci-dma.c | 20 +++-----------------
2 files changed, 3 insertions(+), 18 deletions(-)

diff --git a/arch/x86/include/asm/iommu.h b/arch/x86/include/asm/iommu.h
index baedab8ac538..b91623d521d9 100644
--- a/arch/x86/include/asm/iommu.h
+++ b/arch/x86/include/asm/iommu.h
@@ -4,7 +4,6 @@

extern int force_iommu, no_iommu;
extern int iommu_detected;
-extern int iommu_pass_through;

/* 10 seconds */
#define DMAR_OPERATION_TIMEOUT ((cycles_t) tsc_khz*10*1000)
diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c
index f62b498b18fb..fa4352dce491 100644
--- a/arch/x86/kernel/pci-dma.c
+++ b/arch/x86/kernel/pci-dma.c
@@ -1,6 +1,7 @@
// SPDX-License-Identifier: GPL-2.0
#include <linux/dma-direct.h>
#include <linux/dma-debug.h>
+#include <linux/iommu.h>
#include <linux/dmar.h>
#include <linux/export.h>
#include <linux/memblock.h>
@@ -34,21 +35,6 @@ int no_iommu __read_mostly;
/* Set this to 1 if there is a HW IOMMU in the system */
int iommu_detected __read_mostly = 0;

-/*
- * This variable becomes 1 if iommu=pt is passed on the kernel command line.
- * If this variable is 1, IOMMU implementations do no DMA translation for
- * devices and allow every device to access to whole physical memory. This is
- * useful if a user wants to use an IOMMU only for KVM device assignment to
- * guests and not for driver dma translation.
- * It is also possible to disable by default in kernel config, and enable with
- * iommu=nopt at boot time.
- */
-#ifdef CONFIG_IOMMU_DEFAULT_PASSTHROUGH
-int iommu_pass_through __read_mostly = 1;
-#else
-int iommu_pass_through __read_mostly;
-#endif
-
extern struct iommu_table_entry __iommu_table[], __iommu_table_end[];

void __init pci_iommu_alloc(void)
@@ -120,9 +106,9 @@ static __init int iommu_setup(char *p)
swiotlb = 1;
#endif
if (!strncmp(p, "pt", 2))
- iommu_pass_through = 1;
+ iommu_set_default_passthrough(true);
if (!strncmp(p, "nopt", 4))
- iommu_pass_through = 0;
+ iommu_set_default_translated(true);

gart_parse_options(p);

--
2.16.4