Merge tag 'iommu-updates-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

Pull iommu updates from Joerg Roedel:

 - batched unmap support for the IOMMU-API

 - support for unlocked command queueing in the ARM-SMMU driver

 - rework the ATS support in the ARM-SMMU driver

 - more refactoring in the ARM-SMMU driver to support hardware
   implemention specific quirks and errata

 - bounce buffering DMA-API implementatation in the Intel VT-d driver
   for untrusted devices (like Thunderbolt devices)

 - fixes for runtime PM support in the OMAP iommu driver

 - MT8183 IOMMU support in the Mediatek IOMMU driver

 - rework of the way the IOMMU core sets the default domain type for
   groups. Changing the default domain type on x86 does not require two
   kernel parameters anymore.

 - more smaller fixes and cleanups

* tag 'iommu-updates-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (113 commits)
  iommu/vt-d: Declare Broadwell igfx dmar support snafu
  iommu/vt-d: Add Scalable Mode fault information
  iommu/vt-d: Use bounce buffer for untrusted devices
  iommu/vt-d: Add trace events for device dma map/unmap
  iommu/vt-d: Don't switch off swiotlb if bounce page is used
  iommu/vt-d: Check whether device requires bounce buffer
  swiotlb: Split size parameter to map/unmap APIs
  iommu/omap: Mark pm functions __maybe_unused
  iommu/ipmmu-vmsa: Disable cache snoop transactions on R-Car Gen3
  iommu/ipmmu-vmsa: Move IMTTBCR_SL0_TWOBIT_* to restore sort order
  iommu: Don't use sme_active() in generic code
  iommu/arm-smmu-v3: Fix build error without CONFIG_PCI_ATS
  iommu/qcom: Use struct_size() helper
  iommu: Remove wrong default domain comments
  iommu/dma: Fix for dereferencing before null checking
  iommu/mediatek: Clean up struct mtk_smi_iommu
  memory: mtk-smi: Get rid of need_larbid
  iommu/mediatek: Fix VLD_PA_RNG register backup when suspend
  memory: mtk-smi: Add bus_sel for mt8183
  memory: mtk-smi: Invoke pm runtime_callback to enable clocks
  ...

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);