Merge tag 'iommu-updates-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

Pull iommu updates from Joerg Roedel:

 - Make the dma-iommu code more generic so that it can be used outside
   of the ARM context with other IOMMU drivers. Goal is to make use of
   it on x86 too.

 - Generic IOMMU domain support for the Intel VT-d driver. This driver
   now makes more use of common IOMMU code to allocate default domains
   for the devices it handles.

 - An IOMMU fault reporting API to userspace. With that the IOMMU fault
   handling can be done in user-space, for example to forward the faults
   to a VM.

 - Better handling for reserved regions requested by the firmware. These
   can be 'relaxed' now, meaning that those don't prevent a device being
   attached to a VM.

 - Suspend/Resume support for the Renesas IOMMU driver.

 - Added support for dumping SVA related fields of the DMAR table in the
   Intel VT-d driver via debugfs.

 - A pile of smaller fixes and cleanups.

* tag 'iommu-updates-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (90 commits)
  iommu/omap: No need to check return value of debugfs_create functions
  iommu/arm-smmu-v3: Invalidate ATC when detaching a device
  iommu/arm-smmu-v3: Fix compilation when CONFIG_CMA=n
  iommu/vt-d: Cleanup unused variable
  iommu/amd: Flush not present cache in iommu_map_page
  iommu/amd: Only free resources once on init error
  iommu/amd: Move gart fallback to amd_iommu_init
  iommu/amd: Make iommu_disable safer
  iommu/io-pgtable: Support non-coherent page tables
  iommu/io-pgtable: Replace IO_PGTABLE_QUIRK_NO_DMA with specific flag
  iommu/io-pgtable-arm: Add support to use system cache
  iommu/arm-smmu-v3: Increase maximum size of queues
  iommu/vt-d: Silence a variable set but not used
  iommu/vt-d: Remove an unused variable "length"
  iommu: Fix integer truncation
  iommu: Add padding to struct iommu_fault
  iommu/vt-d: Consolidate domain_init() to avoid duplication
  iommu/vt-d: Cleanup after delegating DMA domain to generic iommu
  iommu/vt-d: Fix suspicious RCU usage in probe_acpi_namespace_devices()
  iommu/vt-d: Allow DMA domain attaching to rmrr locked device
  ...

1 files changed, 24 insertions, 21 deletions

diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c
index 07d84dbab564..eb104c719629 100644
--- a/drivers/iommu/amd_iommu_init.c
+++ b/drivers/iommu/amd_iommu_init.c
@@ -406,6 +406,9 @@ static void iommu_enable(struct amd_iommu *iommu)
 
 static void iommu_disable(struct amd_iommu *iommu)
 {
+	if (!iommu->mmio_base)
+		return;
+
 	/* Disable command buffer */
 	iommu_feature_disable(iommu, CONTROL_CMDBUF_EN);
 
@@ -2325,15 +2328,6 @@ static void __init free_iommu_resources(void)
 	amd_iommu_dev_table = NULL;
 
 	free_iommu_all();
-
-#ifdef CONFIG_GART_IOMMU
-	/*
-	 * We failed to initialize the AMD IOMMU - try fallback to GART
-	 * if possible.
-	 */
-	gart_iommu_init();
-
-#endif
 }
 
 /* SB IOAPIC is always on this device in AMD systems */
@@ -2625,8 +2619,6 @@ static int __init state_next(void)
 		init_state = ret ? IOMMU_INIT_ERROR : IOMMU_ACPI_FINISHED;
 		if (init_state == IOMMU_ACPI_FINISHED && amd_iommu_disabled) {
 			pr_info("AMD IOMMU disabled on kernel command-line\n");
-			free_dma_resources();
-			free_iommu_resources();
 			init_state = IOMMU_CMDLINE_DISABLED;
 			ret = -EINVAL;
 		}
@@ -2667,6 +2659,19 @@ static int __init state_next(void)
 		BUG();
 	}
 
+	if (ret) {
+		free_dma_resources();
+		if (!irq_remapping_enabled) {
+			disable_iommus();
+			free_iommu_resources();
+		} else {
+			struct amd_iommu *iommu;
+
+			uninit_device_table_dma();
+			for_each_iommu(iommu)
+				iommu_flush_all_caches(iommu);
+		}
+	}
 	return ret;
 }
 
@@ -2740,17 +2745,15 @@ static int __init amd_iommu_init(void)
 	int ret;
 
 	ret = iommu_go_to_state(IOMMU_INITIALIZED);
-	if (ret) {
-		free_dma_resources();
-		if (!irq_remapping_enabled) {
-			disable_iommus();
-			free_iommu_resources();
-		} else {
-			uninit_device_table_dma();
-			for_each_iommu(iommu)
-				iommu_flush_all_caches(iommu);
-		}
+#ifdef CONFIG_GART_IOMMU
+	if (ret && list_empty(&amd_iommu_list)) {
+		/*
+		 * We failed to initialize the AMD IOMMU - try fallback
+		 * to GART if possible.
+		 */
+		gart_iommu_init();
 	}
+#endif
 
 	for_each_iommu(iommu)
 		amd_iommu_debugfs_setup(iommu);