Merge tag 'iommu-updates-v7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/iommu/linux

Pull iommu updates from Joerg Roedel:
 "Core changes:
   - Rust bindings for IO-pgtable code
   - IOMMU page allocation debugging support
   - Disable ATS during PCI resets

  Intel VT-d changes:
   - Skip dev-iotlb flush for inaccessible PCIe device
   - Flush cache for PASID table before using it
   - Use right invalidation method for SVA and NESTED domains
   - Ensure atomicity in context and PASID entry updates

  AMD-Vi changes:
   - Support for nested translations
   - Other minor improvements

  ARM-SMMU-v2 changes:
   - Configure SoC-specific prefetcher settings for Qualcomm's "MDSS"

  ARM-SMMU-v3 changes:
   - Improve CMDQ locking fairness for pathetically small queue sizes
   - Remove tracking of the IAS as this is only relevant for AArch32 and
     was causing C_BAD_STE errors
   - Add device-tree support for NVIDIA's CMDQV extension
   - Allow some hitless transitions for the 'MEV' and 'EATS' STE fields
   - Don't disable ATS for nested S1-bypass nested domains
   - Additions to the kunit selftests"

* tag 'iommu-updates-v7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/iommu/linux: (54 commits)
  iommupt: Always add IOVA range to iotlb_gather in gather_range_pages()
  iommu/amd: serialize sequence allocation under concurrent TLB invalidations
  iommu/amd: Fix type of type parameter to amd_iommufd_hw_info()
  iommu/arm-smmu-v3: Do not set disable_ats unless vSTE is Translate
  iommu/arm-smmu-v3-test: Add nested s1bypass/s1dssbypass coverage
  iommu/arm-smmu-v3: Mark EATS_TRANS safe when computing the update sequence
  iommu/arm-smmu-v3: Mark STE MEV safe when computing the update sequence
  iommu/arm-smmu-v3: Add update_safe bits to fix STE update sequence
  iommu/arm-smmu-v3: Add device-tree support for CMDQV driver
  iommu/tegra241-cmdqv: Decouple driver from ACPI
  iommu/arm-smmu-qcom: Restore ACTLR settings for MDSS on sa8775p
  iommu/vt-d: Fix race condition during PASID entry replacement
  iommu/vt-d: Clear Present bit before tearing down context entry
  iommu/vt-d: Clear Present bit before tearing down PASID entry
  iommu/vt-d: Flush piotlb for SVM and Nested domain
  iommu/vt-d: Flush cache for PASID table before using it
  iommu/vt-d: Flush dev-IOTLB only when PCIe device is accessible in scalable mode
  iommu/vt-d: Skip dev-iotlb flush for inaccessible PCIe device without scalable mode
  rust: iommu: fix `srctree` link warning
  rust: iommu: fix Rust formatting
  ...

1 files changed, 27 insertions, 0 deletions

diff --git a/mm/page_ext.c b/mm/page_ext.c
index d7396a8970e5..e2e92bd27ebd 100644
--- a/mm/page_ext.c
+++ b/mm/page_ext.c
@@ -11,6 +11,7 @@
 #include <linux/page_table_check.h>
 #include <linux/rcupdate.h>
 #include <linux/pgalloc_tag.h>
+#include <linux/iommu-debug-pagealloc.h>
 
 /*
  * struct page extension
@@ -89,6 +90,9 @@ static struct page_ext_operations *page_ext_ops[] __initdata = {
 #ifdef CONFIG_PAGE_TABLE_CHECK
 	&page_table_check_ops,
 #endif
+#ifdef CONFIG_IOMMU_DEBUG_PAGEALLOC
+	&page_iommu_debug_ops,
+#endif
 };
 
 unsigned long page_ext_size;
@@ -535,6 +539,29 @@ struct page_ext *page_ext_get(const struct page *page)
 }
 
 /**
+ * page_ext_from_phys() - Get the page_ext structure for a physical address.
+ * @phys: The physical address to query.
+ *
+ * This function safely gets the `struct page_ext` associated with a given
+ * physical address. It performs validation to ensure the address corresponds
+ * to a valid, online struct page before attempting to access it.
+ * It returns NULL for MMIO, ZONE_DEVICE, holes and offline memory.
+ *
+ * Return: NULL if no page_ext exists for this physical address.
+ * Context: Any context.  Caller may not sleep until they have called
+ * page_ext_put().
+ */
+struct page_ext *page_ext_from_phys(phys_addr_t phys)
+{
+	struct page *page = pfn_to_online_page(__phys_to_pfn(phys));
+
+	if (!page)
+		return NULL;
+
+	return page_ext_get(page);
+}
+
+/**
  * page_ext_put() - Working with page extended information is done.
  * @page_ext: Page extended information received from page_ext_get().
  *