Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

1 files changed, 989 insertions, 0 deletions

diff --git a/drivers/iommu/intel/pasid.c b/drivers/iommu/intel/pasid.c
new file mode 100644
index 000000000..e4f24d3f1
--- /dev/null
+++ b/drivers/iommu/intel/pasid.c
@@ -0,0 +1,989 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * intel-pasid.c - PASID idr, table and entry manipulation
+ *
+ * Copyright (C) 2018 Intel Corporation
+ *
+ * Author: Lu Baolu <baolu.lu@linux.intel.com>
+ */
+
+#define pr_fmt(fmt)	"DMAR: " fmt
+
+#include <linux/bitops.h>
+#include <linux/cpufeature.h>
+#include <linux/dmar.h>
+#include <linux/iommu.h>
+#include <linux/memory.h>
+#include <linux/pci.h>
+#include <linux/pci-ats.h>
+#include <linux/spinlock.h>
+
+#include "iommu.h"
+#include "pasid.h"
+#include "../iommu-pages.h"
+
+/*
+ * Intel IOMMU system wide PASID name space:
+ */
+u32 intel_pasid_max_id = PASID_MAX;
+
+/*
+ * Per device pasid table management:
+ */
+
+/*
+ * Allocate a pasid table for @dev. It should be called in a
+ * single-thread context.
+ */
+int intel_pasid_alloc_table(struct device *dev)
+{
+	struct device_domain_info *info;
+	struct pasid_table *pasid_table;
+	struct pasid_dir_entry *dir;
+	u32 max_pasid = 0;
+	int order, size;
+
+	might_sleep();
+	info = dev_iommu_priv_get(dev);
+	if (WARN_ON(!info || !dev_is_pci(dev)))
+		return -ENODEV;
+	if (WARN_ON(info->pasid_table))
+		return -EEXIST;
+
+	pasid_table = kzalloc_obj(*pasid_table);
+	if (!pasid_table)
+		return -ENOMEM;
+
+	if (info->pasid_supported)
+		max_pasid = min_t(u32, pci_max_pasids(to_pci_dev(dev)),
+				  intel_pasid_max_id);
+
+	size = max_pasid >> (PASID_PDE_SHIFT - 3);
+	order = size ? get_order(size) : 0;
+	dir = iommu_alloc_pages_node_sz(info->iommu->node, GFP_KERNEL,
+					1 << (order + PAGE_SHIFT));
+	if (!dir) {
+		kfree(pasid_table);
+		return -ENOMEM;
+	}
+
+	pasid_table->table = dir;
+	pasid_table->max_pasid = 1 << (order + PAGE_SHIFT + 3);
+	info->pasid_table = pasid_table;
+
+	if (!ecap_coherent(info->iommu->ecap))
+		clflush_cache_range(pasid_table->table, (1 << order) * PAGE_SIZE);
+
+	return 0;
+}
+
+void intel_pasid_free_table(struct device *dev)
+{
+	struct device_domain_info *info;
+	struct pasid_table *pasid_table;
+	struct pasid_dir_entry *dir;
+	struct pasid_entry *table;
+	int i, max_pde;
+
+	info = dev_iommu_priv_get(dev);
+	if (!info || !dev_is_pci(dev) || !info->pasid_table)
+		return;
+
+	pasid_table = info->pasid_table;
+	info->pasid_table = NULL;
+
+	/* Free scalable mode PASID directory tables: */
+	dir = pasid_table->table;
+	max_pde = pasid_table->max_pasid >> PASID_PDE_SHIFT;
+	for (i = 0; i < max_pde; i++) {
+		table = get_pasid_table_from_pde(&dir[i]);
+		iommu_free_pages(table);
+	}
+
+	iommu_free_pages(pasid_table->table);
+	kfree(pasid_table);
+}
+
+struct pasid_table *intel_pasid_get_table(struct device *dev)
+{
+	struct device_domain_info *info;
+
+	info = dev_iommu_priv_get(dev);
+	if (!info)
+		return NULL;
+
+	return info->pasid_table;
+}
+
+static int intel_pasid_get_dev_max_id(struct device *dev)
+{
+	struct device_domain_info *info;
+
+	info = dev_iommu_priv_get(dev);
+	if (!info || !info->pasid_table)
+		return 0;
+
+	return info->pasid_table->max_pasid;
+}
+
+static struct pasid_entry *intel_pasid_get_entry(struct device *dev, u32 pasid)
+{
+	struct device_domain_info *info;
+	struct pasid_table *pasid_table;
+	struct pasid_dir_entry *dir;
+	struct pasid_entry *entries;
+	int dir_index, index;
+
+	pasid_table = intel_pasid_get_table(dev);
+	if (WARN_ON(!pasid_table || pasid >= intel_pasid_get_dev_max_id(dev)))
+		return NULL;
+
+	dir = pasid_table->table;
+	info = dev_iommu_priv_get(dev);
+	dir_index = pasid >> PASID_PDE_SHIFT;
+	index = pasid & PASID_PTE_MASK;
+
+retry:
+	entries = get_pasid_table_from_pde(&dir[dir_index]);
+	if (!entries) {
+		u64 tmp;
+
+		entries = iommu_alloc_pages_node_sz(info->iommu->node,
+						    GFP_ATOMIC, SZ_4K);
+		if (!entries)
+			return NULL;
+
+		if (!ecap_coherent(info->iommu->ecap))
+			clflush_cache_range(entries, VTD_PAGE_SIZE);
+
+		/*
+		 * The pasid directory table entry won't be freed after
+		 * allocation. No worry about the race with free and
+		 * clear. However, this entry might be populated by others
+		 * while we are preparing it. Use theirs with a retry.
+		 */
+		tmp = 0ULL;
+		if (!try_cmpxchg64(&dir[dir_index].val, &tmp,
+				   (u64)virt_to_phys(entries) | PASID_PTE_PRESENT)) {
+			iommu_free_pages(entries);
+			goto retry;
+		}
+		if (!ecap_coherent(info->iommu->ecap))
+			clflush_cache_range(&dir[dir_index].val, sizeof(*dir));
+	}
+
+	return &entries[index];
+}
+
+/*
+ * Interfaces for PASID table entry manipulation:
+ */
+static void
+intel_pasid_clear_entry(struct device *dev, u32 pasid, bool fault_ignore)
+{
+	struct pasid_entry *pe;
+
+	pe = intel_pasid_get_entry(dev, pasid);
+	if (WARN_ON(!pe))
+		return;
+
+	if (fault_ignore && pasid_pte_is_present(pe))
+		pasid_clear_entry_with_fpd(pe);
+	else
+		pasid_clear_entry(pe);
+}
+
+static void
+pasid_cache_invalidation_with_pasid(struct intel_iommu *iommu,
+				    u16 did, u32 pasid)
+{
+	struct qi_desc desc;
+
+	desc.qw0 = QI_PC_DID(did) | QI_PC_GRAN(QI_PC_PASID_SEL) |
+		QI_PC_PASID(pasid) | QI_PC_TYPE;
+	desc.qw1 = 0;
+	desc.qw2 = 0;
+	desc.qw3 = 0;
+
+	qi_submit_sync(iommu, &desc, 1, 0);
+}
+
+static void
+devtlb_invalidation_with_pasid(struct intel_iommu *iommu,
+			       struct device *dev, u32 pasid)
+{
+	struct device_domain_info *info;
+	u16 sid, qdep, pfsid;
+
+	info = dev_iommu_priv_get(dev);
+	if (!info || !info->ats_enabled)
+		return;
+
+	if (!pci_device_is_present(to_pci_dev(dev)))
+		return;
+
+	sid = PCI_DEVID(info->bus, info->devfn);
+	qdep = info->ats_qdep;
+	pfsid = info->pfsid;
+
+	/*
+	 * When PASID 0 is used, it indicates RID2PASID(DMA request w/o PASID),
+	 * devTLB flush w/o PASID should be used. For non-zero PASID under
+	 * SVA usage, device could do DMA with multiple PASIDs. It is more
+	 * efficient to flush devTLB specific to the PASID.
+	 */
+	if (pasid == IOMMU_NO_PASID)
+		qi_flush_dev_iotlb(iommu, sid, pfsid, qdep, 0, 64 - VTD_PAGE_SHIFT);
+	else
+		qi_flush_dev_iotlb_pasid(iommu, sid, pfsid, pasid, qdep, 0, 64 - VTD_PAGE_SHIFT);
+}
+
+void intel_pasid_tear_down_entry(struct intel_iommu *iommu, struct device *dev,
+				 u32 pasid, bool fault_ignore)
+{
+	struct pasid_entry *pte;
+	u16 did, pgtt;
+
+	spin_lock(&iommu->lock);
+	pte = intel_pasid_get_entry(dev, pasid);
+	if (WARN_ON(!pte)) {
+		spin_unlock(&iommu->lock);
+		return;
+	}
+
+	if (!pasid_pte_is_present(pte)) {
+		if (!pasid_pte_is_fault_disabled(pte)) {
+			WARN_ON(READ_ONCE(pte->val[0]) != 0);
+			spin_unlock(&iommu->lock);
+			return;
+		}
+
+		/*
+		 * When a PASID is used for SVA by a device, it's possible
+		 * that the pasid entry is non-present with the Fault
+		 * Processing Disabled bit set. Clear the pasid entry and
+		 * drain the PRQ for the PASID before return.
+		 */
+		pasid_clear_entry(pte);
+		spin_unlock(&iommu->lock);
+		intel_iommu_drain_pasid_prq(dev, pasid);
+
+		return;
+	}
+
+	did = pasid_get_domain_id(pte);
+	pgtt = pasid_pte_get_pgtt(pte);
+	pasid_clear_present(pte);
+	spin_unlock(&iommu->lock);
+
+	if (!ecap_coherent(iommu->ecap))
+		clflush_cache_range(pte, sizeof(*pte));
+
+	pasid_cache_invalidation_with_pasid(iommu, did, pasid);
+
+	if (pgtt == PASID_ENTRY_PGTT_PT || pgtt == PASID_ENTRY_PGTT_FL_ONLY)
+		qi_flush_piotlb_all(iommu, did, pasid);
+	else
+		iommu->flush.flush_iotlb(iommu, did, 0, 0, DMA_TLB_DSI_FLUSH);
+
+	devtlb_invalidation_with_pasid(iommu, dev, pasid);
+	intel_pasid_clear_entry(dev, pasid, fault_ignore);
+	if (!ecap_coherent(iommu->ecap))
+		clflush_cache_range(pte, sizeof(*pte));
+
+	if (!fault_ignore)
+		intel_iommu_drain_pasid_prq(dev, pasid);
+}
+
+/*
+ * This function flushes cache for a newly setup pasid table entry.
+ * Caller of it should not modify the in-use pasid table entries.
+ */
+static void pasid_flush_caches(struct intel_iommu *iommu,
+				struct pasid_entry *pte,
+			       u32 pasid, u16 did)
+{
+	if (!ecap_coherent(iommu->ecap))
+		clflush_cache_range(pte, sizeof(*pte));
+
+	if (cap_caching_mode(iommu->cap)) {
+		pasid_cache_invalidation_with_pasid(iommu, did, pasid);
+		qi_flush_piotlb_all(iommu, did, pasid);
+	} else {
+		iommu_flush_write_buffer(iommu);
+	}
+}
+
+/*
+ * This function is supposed to be used after caller updates the fields
+ * except for the SSADE and P bit of a pasid table entry. It does the
+ * below:
+ * - Flush cacheline if needed
+ * - Flush the caches per Table 28 ”Guidance to Software for Invalidations“
+ *   of VT-d spec 5.0.
+ */
+static void intel_pasid_flush_present(struct intel_iommu *iommu,
+				      struct device *dev,
+				      u32 pasid, u16 did,
+				      struct pasid_entry *pte)
+{
+	if (!ecap_coherent(iommu->ecap))
+		clflush_cache_range(pte, sizeof(*pte));
+
+	/*
+	 * VT-d spec 5.0 table28 states guides for cache invalidation:
+	 *
+	 * - PASID-selective-within-Domain PASID-cache invalidation
+	 * - PASID-selective PASID-based IOTLB invalidation
+	 * - If (pasid is RID_PASID)
+	 *    - Global Device-TLB invalidation to affected functions
+	 *   Else
+	 *    - PASID-based Device-TLB invalidation (with S=1 and
+	 *      Addr[63:12]=0x7FFFFFFF_FFFFF) to affected functions
+	 */
+	pasid_cache_invalidation_with_pasid(iommu, did, pasid);
+	qi_flush_piotlb_all(iommu, did, pasid);
+
+	devtlb_invalidation_with_pasid(iommu, dev, pasid);
+}
+
+/*
+ * Set up the scalable mode pasid table entry for first only
+ * translation type.
+ */
+static void pasid_pte_config_first_level(struct intel_iommu *iommu,
+					 struct pasid_entry *pte,
+					 phys_addr_t fsptptr, u16 did,
+					 int flags)
+{
+	lockdep_assert_held(&iommu->lock);
+
+	pasid_clear_entry(pte);
+
+	/* Setup the first level page table pointer: */
+	pasid_set_flptr(pte, fsptptr);
+
+	if (flags & PASID_FLAG_FL5LP)
+		pasid_set_flpm(pte, 1);
+
+	if (flags & PASID_FLAG_PAGE_SNOOP)
+		pasid_set_pgsnp(pte);
+
+	pasid_set_domain_id(pte, did);
+	pasid_set_address_width(pte, iommu->agaw);
+	pasid_set_page_snoop(pte, flags & PASID_FLAG_PWSNP);
+
+	/* Setup Present and PASID Granular Transfer Type: */
+	pasid_set_translation_type(pte, PASID_ENTRY_PGTT_FL_ONLY);
+	pasid_set_present(pte);
+}
+
+int intel_pasid_setup_first_level(struct intel_iommu *iommu, struct device *dev,
+				  phys_addr_t fsptptr, u32 pasid, u16 did,
+				  int flags)
+{
+	struct pasid_entry *pte;
+
+	if (!ecap_flts(iommu->ecap)) {
+		pr_err("No first level translation support on %s\n",
+		       iommu->name);
+		return -EINVAL;
+	}
+
+	if ((flags & PASID_FLAG_FL5LP) && !cap_fl5lp_support(iommu->cap)) {
+		pr_err("No 5-level paging support for first-level on %s\n",
+		       iommu->name);
+		return -EINVAL;
+	}
+
+	spin_lock(&iommu->lock);
+	pte = intel_pasid_get_entry(dev, pasid);
+	if (!pte) {
+		spin_unlock(&iommu->lock);
+		return -ENODEV;
+	}
+
+	if (pasid_pte_is_present(pte)) {
+		spin_unlock(&iommu->lock);
+		return -EBUSY;
+	}
+
+	pasid_pte_config_first_level(iommu, pte, fsptptr, did, flags);
+
+	spin_unlock(&iommu->lock);
+
+	pasid_flush_caches(iommu, pte, pasid, did);
+
+	return 0;
+}
+
+/*
+ * Set up the scalable mode pasid entry for second only translation type.
+ */
+static void pasid_pte_config_second_level(struct intel_iommu *iommu,
+					  struct pasid_entry *pte,
+					  struct dmar_domain *domain, u16 did)
+{
+	struct pt_iommu_vtdss_hw_info pt_info;
+
+	lockdep_assert_held(&iommu->lock);
+
+	pt_iommu_vtdss_hw_info(&domain->sspt, &pt_info);
+	pasid_clear_entry(pte);
+	pasid_set_domain_id(pte, did);
+	pasid_set_slptr(pte, pt_info.ssptptr);
+	pasid_set_address_width(pte, pt_info.aw);
+	pasid_set_translation_type(pte, PASID_ENTRY_PGTT_SL_ONLY);
+	pasid_set_fault_enable(pte);
+	pasid_set_page_snoop(pte, !(domain->sspt.vtdss_pt.common.features &
+				    BIT(PT_FEAT_DMA_INCOHERENT)));
+	if (domain->dirty_tracking)
+		pasid_set_ssade(pte);
+
+	pasid_set_present(pte);
+}
+
+int intel_pasid_setup_second_level(struct intel_iommu *iommu,
+				   struct dmar_domain *domain,
+				   struct device *dev, u32 pasid)
+{
+	struct pasid_entry *pte;
+	u16 did;
+
+
+	/*
+	 * If hardware advertises no support for second level
+	 * translation, return directly.
+	 */
+	if (!ecap_slts(iommu->ecap)) {
+		pr_err("No second level translation support on %s\n",
+		       iommu->name);
+		return -EINVAL;
+	}
+
+	did = domain_id_iommu(domain, iommu);
+
+	spin_lock(&iommu->lock);
+	pte = intel_pasid_get_entry(dev, pasid);
+	if (!pte) {
+		spin_unlock(&iommu->lock);
+		return -ENODEV;
+	}
+
+	if (pasid_pte_is_present(pte)) {
+		spin_unlock(&iommu->lock);
+		return -EBUSY;
+	}
+
+	pasid_pte_config_second_level(iommu, pte, domain, did);
+	spin_unlock(&iommu->lock);
+
+	pasid_flush_caches(iommu, pte, pasid, did);
+
+	return 0;
+}
+
+/*
+ * Set up dirty tracking on a second only or nested translation type.
+ */
+int intel_pasid_setup_dirty_tracking(struct intel_iommu *iommu,
+				     struct device *dev, u32 pasid,
+				     bool enabled)
+{
+	struct pasid_entry *pte;
+	u16 did, pgtt;
+
+	spin_lock(&iommu->lock);
+
+	pte = intel_pasid_get_entry(dev, pasid);
+	if (!pte) {
+		spin_unlock(&iommu->lock);
+		dev_err_ratelimited(
+			dev, "Failed to get pasid entry of PASID %d\n", pasid);
+		return -ENODEV;
+	}
+
+	did = pasid_get_domain_id(pte);
+	pgtt = pasid_pte_get_pgtt(pte);
+	if (pgtt != PASID_ENTRY_PGTT_SL_ONLY &&
+	    pgtt != PASID_ENTRY_PGTT_NESTED) {
+		spin_unlock(&iommu->lock);
+		dev_err_ratelimited(
+			dev,
+			"Dirty tracking not supported on translation type %d\n",
+			pgtt);
+		return -EOPNOTSUPP;
+	}
+
+	if (pasid_get_ssade(pte) == enabled) {
+		spin_unlock(&iommu->lock);
+		return 0;
+	}
+
+	if (enabled)
+		pasid_set_ssade(pte);
+	else
+		pasid_clear_ssade(pte);
+	spin_unlock(&iommu->lock);
+
+	if (!ecap_coherent(iommu->ecap))
+		clflush_cache_range(pte, sizeof(*pte));
+
+	/*
+	 * From VT-d spec table 25 "Guidance to Software for Invalidations":
+	 *
+	 * - PASID-selective-within-Domain PASID-cache invalidation
+	 *   If (PGTT=SS or Nested)
+	 *    - Domain-selective IOTLB invalidation
+	 *   Else
+	 *    - PASID-selective PASID-based IOTLB invalidation
+	 * - If (pasid is RID_PASID)
+	 *    - Global Device-TLB invalidation to affected functions
+	 *   Else
+	 *    - PASID-based Device-TLB invalidation (with S=1 and
+	 *      Addr[63:12]=0x7FFFFFFF_FFFFF) to affected functions
+	 */
+	pasid_cache_invalidation_with_pasid(iommu, did, pasid);
+
+	iommu->flush.flush_iotlb(iommu, did, 0, 0, DMA_TLB_DSI_FLUSH);
+
+	devtlb_invalidation_with_pasid(iommu, dev, pasid);
+
+	return 0;
+}
+
+/*
+ * Set up the scalable mode pasid entry for passthrough translation type.
+ */
+static void pasid_pte_config_pass_through(struct intel_iommu *iommu,
+					  struct pasid_entry *pte, u16 did)
+{
+	lockdep_assert_held(&iommu->lock);
+
+	pasid_clear_entry(pte);
+	pasid_set_domain_id(pte, did);
+	pasid_set_address_width(pte, iommu->agaw);
+	pasid_set_translation_type(pte, PASID_ENTRY_PGTT_PT);
+	pasid_set_fault_enable(pte);
+	pasid_set_page_snoop(pte, !!ecap_smpwc(iommu->ecap));
+	pasid_set_present(pte);
+}
+
+int intel_pasid_setup_pass_through(struct intel_iommu *iommu,
+				   struct device *dev, u32 pasid)
+{
+	u16 did = FLPT_DEFAULT_DID;
+	struct pasid_entry *pte;
+
+	spin_lock(&iommu->lock);
+	pte = intel_pasid_get_entry(dev, pasid);
+	if (!pte) {
+		spin_unlock(&iommu->lock);
+		return -ENODEV;
+	}
+
+	if (pasid_pte_is_present(pte)) {
+		spin_unlock(&iommu->lock);
+		return -EBUSY;
+	}
+
+	pasid_pte_config_pass_through(iommu, pte, did);
+	spin_unlock(&iommu->lock);
+
+	pasid_flush_caches(iommu, pte, pasid, did);
+
+	return 0;
+}
+
+/*
+ * Set the page snoop control for a pasid entry which has been set up.
+ */
+void intel_pasid_setup_page_snoop_control(struct intel_iommu *iommu,
+					  struct device *dev, u32 pasid)
+{
+	struct pasid_entry *pte;
+	u16 did;
+
+	spin_lock(&iommu->lock);
+	pte = intel_pasid_get_entry(dev, pasid);
+	if (WARN_ON(!pte || !pasid_pte_is_present(pte))) {
+		spin_unlock(&iommu->lock);
+		return;
+	}
+
+	pasid_set_pgsnp(pte);
+	did = pasid_get_domain_id(pte);
+	spin_unlock(&iommu->lock);
+
+	intel_pasid_flush_present(iommu, dev, pasid, did, pte);
+}
+
+static void pasid_pte_config_nested(struct intel_iommu *iommu,
+				    struct pasid_entry *pte,
+				    struct iommu_hwpt_vtd_s1 *s1_cfg,
+				    struct dmar_domain *s2_domain,
+				    u16 did)
+{
+	struct pt_iommu_vtdss_hw_info pt_info;
+
+	lockdep_assert_held(&iommu->lock);
+
+	pt_iommu_vtdss_hw_info(&s2_domain->sspt, &pt_info);
+
+	pasid_clear_entry(pte);
+
+	if (s1_cfg->addr_width == ADDR_WIDTH_5LEVEL)
+		pasid_set_flpm(pte, 1);
+
+	pasid_set_flptr(pte, s1_cfg->pgtbl_addr);
+
+	if (s1_cfg->flags & IOMMU_VTD_S1_SRE) {
+		pasid_set_sre(pte);
+		if (s1_cfg->flags & IOMMU_VTD_S1_WPE)
+			pasid_set_wpe(pte);
+	}
+
+	if (s1_cfg->flags & IOMMU_VTD_S1_EAFE)
+		pasid_set_eafe(pte);
+
+	if (s2_domain->force_snooping)
+		pasid_set_pgsnp(pte);
+
+	pasid_set_slptr(pte, pt_info.ssptptr);
+	pasid_set_fault_enable(pte);
+	pasid_set_domain_id(pte, did);
+	pasid_set_address_width(pte, pt_info.aw);
+	pasid_set_page_snoop(pte, !(s2_domain->sspt.vtdss_pt.common.features &
+				    BIT(PT_FEAT_DMA_INCOHERENT)));
+	if (s2_domain->dirty_tracking)
+		pasid_set_ssade(pte);
+	pasid_set_translation_type(pte, PASID_ENTRY_PGTT_NESTED);
+	pasid_set_present(pte);
+}
+
+/**
+ * intel_pasid_setup_nested() - Set up PASID entry for nested translation.
+ * @iommu:      IOMMU which the device belong to
+ * @dev:        Device to be set up for translation
+ * @pasid:      PASID to be programmed in the device PASID table
+ * @domain:     User stage-1 domain nested on a stage-2 domain
+ *
+ * This is used for nested translation. The input domain should be
+ * nested type and nested on a parent with 'is_nested_parent' flag
+ * set.
+ */
+int intel_pasid_setup_nested(struct intel_iommu *iommu, struct device *dev,
+			     u32 pasid, struct dmar_domain *domain)
+{
+	struct iommu_hwpt_vtd_s1 *s1_cfg = &domain->s1_cfg;
+	struct dmar_domain *s2_domain = domain->s2_domain;
+	u16 did = domain_id_iommu(domain, iommu);
+	struct pasid_entry *pte;
+
+	/* Address width should match the address width supported by hardware */
+	switch (s1_cfg->addr_width) {
+	case ADDR_WIDTH_4LEVEL:
+		break;
+	case ADDR_WIDTH_5LEVEL:
+		if (!cap_fl5lp_support(iommu->cap)) {
+			dev_err_ratelimited(dev,
+					    "5-level paging not supported\n");
+			return -EINVAL;
+		}
+		break;
+	default:
+		dev_err_ratelimited(dev, "Invalid stage-1 address width %d\n",
+				    s1_cfg->addr_width);
+		return -EINVAL;
+	}
+
+	if ((s1_cfg->flags & IOMMU_VTD_S1_SRE) && !ecap_srs(iommu->ecap)) {
+		pr_err_ratelimited("No supervisor request support on %s\n",
+				   iommu->name);
+		return -EINVAL;
+	}
+
+	if ((s1_cfg->flags & IOMMU_VTD_S1_EAFE) && !ecap_eafs(iommu->ecap)) {
+		pr_err_ratelimited("No extended access flag support on %s\n",
+				   iommu->name);
+		return -EINVAL;
+	}
+
+	spin_lock(&iommu->lock);
+	pte = intel_pasid_get_entry(dev, pasid);
+	if (!pte) {
+		spin_unlock(&iommu->lock);
+		return -ENODEV;
+	}
+	if (pasid_pte_is_present(pte)) {
+		spin_unlock(&iommu->lock);
+		return -EBUSY;
+	}
+
+	pasid_pte_config_nested(iommu, pte, s1_cfg, s2_domain, did);
+	spin_unlock(&iommu->lock);
+
+	pasid_flush_caches(iommu, pte, pasid, did);
+
+	return 0;
+}
+
+/*
+ * Interfaces to setup or teardown a pasid table to the scalable-mode
+ * context table entry:
+ */
+
+static void device_pasid_table_teardown(struct device *dev, u8 bus, u8 devfn)
+{
+	struct device_domain_info *info = dev_iommu_priv_get(dev);
+	struct intel_iommu *iommu = info->iommu;
+	struct context_entry *context;
+	u16 did;
+
+	spin_lock(&iommu->lock);
+	context = iommu_context_addr(iommu, bus, devfn, false);
+	if (!context) {
+		spin_unlock(&iommu->lock);
+		return;
+	}
+
+	did = context_domain_id(context);
+	context_clear_present(context);
+	__iommu_flush_cache(iommu, context, sizeof(*context));
+	spin_unlock(&iommu->lock);
+	intel_context_flush_no_pasid(info, context, did, PCI_DEVID(bus, devfn));
+	context_clear_entry(context);
+	__iommu_flush_cache(iommu, context, sizeof(*context));
+}
+
+static int pci_pasid_table_teardown(struct pci_dev *pdev, u16 alias, void *data)
+{
+	struct device *dev = data;
+
+	if (dev == &pdev->dev)
+		device_pasid_table_teardown(dev, PCI_BUS_NUM(alias), alias & 0xff);
+
+	return 0;
+}
+
+void intel_pasid_teardown_sm_context(struct device *dev)
+{
+	struct device_domain_info *info = dev_iommu_priv_get(dev);
+
+	if (!dev_is_pci(dev)) {
+		device_pasid_table_teardown(dev, info->bus, info->devfn);
+		return;
+	}
+
+	pci_for_each_dma_alias(to_pci_dev(dev), pci_pasid_table_teardown, dev);
+}
+
+/*
+ * Get the PASID directory size for scalable mode context entry.
+ * Value of X in the PDTS field of a scalable mode context entry
+ * indicates PASID directory with 2^(X + 7) entries.
+ */
+static unsigned long context_get_sm_pds(struct pasid_table *table)
+{
+	unsigned long pds, max_pde;
+
+	max_pde = table->max_pasid >> PASID_PDE_SHIFT;
+	pds = find_first_bit(&max_pde, MAX_NR_PASID_BITS);
+	if (pds < 7)
+		return 0;
+
+	return pds - 7;
+}
+
+static int context_entry_set_pasid_table(struct context_entry *context,
+					 struct device *dev)
+{
+	struct device_domain_info *info = dev_iommu_priv_get(dev);
+	struct pasid_table *table = info->pasid_table;
+	struct intel_iommu *iommu = info->iommu;
+	unsigned long pds;
+
+	context_clear_entry(context);
+
+	pds = context_get_sm_pds(table);
+	context->lo = (u64)virt_to_phys(table->table) | context_pdts(pds);
+	context_set_sm_rid2pasid(context, IOMMU_NO_PASID);
+
+	if (info->ats_supported)
+		context_set_sm_dte(context);
+	if (info->pasid_supported)
+		context_set_pasid(context);
+	if (info->pri_supported)
+		context_set_sm_pre(context);
+
+	context_set_fault_enable(context);
+	context_set_present(context);
+	__iommu_flush_cache(iommu, context, sizeof(*context));
+
+	return 0;
+}
+
+static int device_pasid_table_setup(struct device *dev, u8 bus, u8 devfn)
+{
+	struct device_domain_info *info = dev_iommu_priv_get(dev);
+	struct intel_iommu *iommu = info->iommu;
+	struct context_entry *context;
+
+	spin_lock(&iommu->lock);
+	context = iommu_context_addr(iommu, bus, devfn, true);
+	if (!context) {
+		spin_unlock(&iommu->lock);
+		return -ENOMEM;
+	}
+
+	if (context_present(context) && !context_copied(iommu, bus, devfn)) {
+		spin_unlock(&iommu->lock);
+		return 0;
+	}
+
+	if (context_copied(iommu, bus, devfn)) {
+		context_clear_present(context);
+		__iommu_flush_cache(iommu, context, sizeof(*context));
+
+		/*
+		 * For kdump cases, old valid entries may be cached due to
+		 * the in-flight DMA and copied pgtable, but there is no
+		 * unmapping behaviour for them, thus we need explicit cache
+		 * flushes for all affected domain IDs and PASIDs used in
+		 * the copied PASID table. Given that we have no idea about
+		 * which domain IDs and PASIDs were used in the copied tables,
+		 * upgrade them to global PASID and IOTLB cache invalidation.
+		 */
+		iommu->flush.flush_context(iommu, 0,
+					   PCI_DEVID(bus, devfn),
+					   DMA_CCMD_MASK_NOBIT,
+					   DMA_CCMD_DEVICE_INVL);
+		qi_flush_pasid_cache(iommu, 0, QI_PC_GLOBAL, 0);
+		iommu->flush.flush_iotlb(iommu, 0, 0, 0, DMA_TLB_GLOBAL_FLUSH);
+		devtlb_invalidation_with_pasid(iommu, dev, IOMMU_NO_PASID);
+
+		context_clear_entry(context);
+		__iommu_flush_cache(iommu, context, sizeof(*context));
+
+		/*
+		 * At this point, the device is supposed to finish reset at
+		 * its driver probe stage, so no in-flight DMA will exist,
+		 * and we don't need to worry anymore hereafter.
+		 */
+		clear_context_copied(iommu, bus, devfn);
+	}
+
+	context_entry_set_pasid_table(context, dev);
+	spin_unlock(&iommu->lock);
+
+	/*
+	 * It's a non-present to present mapping. If hardware doesn't cache
+	 * non-present entry we don't need to flush the caches. If it does
+	 * cache non-present entries, then it does so in the special
+	 * domain #0, which we have to flush:
+	 */
+	if (cap_caching_mode(iommu->cap)) {
+		iommu->flush.flush_context(iommu, 0,
+					   PCI_DEVID(bus, devfn),
+					   DMA_CCMD_MASK_NOBIT,
+					   DMA_CCMD_DEVICE_INVL);
+		iommu->flush.flush_iotlb(iommu, 0, 0, 0, DMA_TLB_DSI_FLUSH);
+	}
+
+	return 0;
+}
+
+static int pci_pasid_table_setup(struct pci_dev *pdev, u16 alias, void *data)
+{
+	struct device *dev = data;
+
+	if (dev != &pdev->dev)
+		return 0;
+
+	return device_pasid_table_setup(dev, PCI_BUS_NUM(alias), alias & 0xff);
+}
+
+/*
+ * Set the device's PASID table to its context table entry.
+ *
+ * The PASID table is set to the context entries of both device itself
+ * and its alias requester ID for DMA.
+ */
+int intel_pasid_setup_sm_context(struct device *dev)
+{
+	struct device_domain_info *info = dev_iommu_priv_get(dev);
+
+	if (!dev_is_pci(dev))
+		return device_pasid_table_setup(dev, info->bus, info->devfn);
+
+	return pci_for_each_dma_alias(to_pci_dev(dev), pci_pasid_table_setup, dev);
+}
+
+/*
+ * Global Device-TLB invalidation following changes in a context entry which
+ * was present.
+ */
+static void __context_flush_dev_iotlb(struct device_domain_info *info)
+{
+	if (!info->ats_enabled)
+		return;
+
+	/*
+	 * Skip dev-IOTLB flush for inaccessible PCIe devices to prevent the
+	 * Intel IOMMU from waiting indefinitely for an ATS invalidation that
+	 * cannot complete.
+	 */
+	if (!pci_device_is_present(to_pci_dev(info->dev)))
+		return;
+
+	qi_flush_dev_iotlb(info->iommu, PCI_DEVID(info->bus, info->devfn),
+			   info->pfsid, info->ats_qdep, 0, MAX_AGAW_PFN_WIDTH);
+
+	/*
+	 * There is no guarantee that the device DMA is stopped when it reaches
+	 * here. Therefore, always attempt the extra device TLB invalidation
+	 * quirk. The impact on performance is acceptable since this is not a
+	 * performance-critical path.
+	 */
+	quirk_extra_dev_tlb_flush(info, 0, MAX_AGAW_PFN_WIDTH, IOMMU_NO_PASID,
+				  info->ats_qdep);
+}
+
+/*
+ * Cache invalidations after change in a context table entry that was present
+ * according to the Spec 6.5.3.3 (Guidance to Software for Invalidations).
+ * This helper can only be used when IOMMU is working in the legacy mode or
+ * IOMMU is in scalable mode but all PASID table entries of the device are
+ * non-present.
+ *
+ * @sid identifies the context entry that was modified, which may be a DMA
+ * alias of @info->dev rather than its own requester ID.
+ */
+void intel_context_flush_no_pasid(struct device_domain_info *info,
+				  struct context_entry *context, u16 did, u16 sid)
+{
+	struct intel_iommu *iommu = info->iommu;
+
+	/*
+	 * Device-selective context-cache invalidation. The Domain-ID field
+	 * of the Context-cache Invalidate Descriptor is ignored by hardware
+	 * when operating in scalable mode. Therefore the @did value doesn't
+	 * matter in scalable mode.
+	 */
+	iommu->flush.flush_context(iommu, did, sid,
+				   DMA_CCMD_MASK_NOBIT, DMA_CCMD_DEVICE_INVL);
+
+	/*
+	 * For legacy mode:
+	 * - Domain-selective IOTLB invalidation
+	 * - Global Device-TLB invalidation to all affected functions
+	 */
+	if (!sm_supported(iommu)) {
+		iommu->flush.flush_iotlb(iommu, did, 0, 0, DMA_TLB_DSI_FLUSH);
+		__context_flush_dev_iotlb(info);
+
+		return;
+	}
+
+	__context_flush_dev_iotlb(info);
+}