Merge tag 'iommu-updates-v4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

Pull IOMMU updates from Joerg Roedel:
 "This time with bigger changes than usual:

   - A new IOMMU driver for the ARM SMMUv3.

     This IOMMU is pretty different from SMMUv1 and v2 in that it is
     configured through in-memory structures and not through the MMIO
     register region.  The ARM SMMUv3 also supports IO demand paging for
     PCI devices with PRI/PASID capabilities, but this is not
     implemented in the driver yet.

   - Lots of cleanups and device-tree support for the Exynos IOMMU
     driver.  This is part of the effort to bring Exynos DRM support
     upstream.

   - Introduction of default domains into the IOMMU core code.

     The rationale behind this is to move functionalily out of the IOMMU
     drivers to common code to get to a unified behavior between
     different drivers.  The patches here introduce a default domain for
     iommu-groups (isolation groups).

     A device will now always be attached to a domain, either the
     default domain or another domain handled by the device driver.  The
     IOMMU drivers have to be modified to make use of that feature.  So
     long the AMD IOMMU driver is converted, with others to follow.

   - Patches for the Intel VT-d drvier to fix DMAR faults that happen
     when a kdump kernel boots.

     When the kdump kernel boots it re-initializes the IOMMU hardware,
     which destroys all mappings from the crashed kernel.  As this
     happens before the endpoint devices are re-initialized, any
     in-flight DMA causes a DMAR fault.  These faults cause PCI master
     aborts, which some devices can't handle properly and go into an
     undefined state, so that the device driver in the kdump kernel
     fails to initialize them and the dump fails.

     This is now fixed by copying over the mapping structures (only
     context tables and interrupt remapping tables) from the old kernel
     and keep the old mappings in place until the device driver of the
     new kernel takes over.  This emulates the the behavior without an
     IOMMU to the best degree possible.

   - A couple of other small fixes and cleanups"

* tag 'iommu-updates-v4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (69 commits)
  iommu/amd: Handle large pages correctly in free_pagetable
  iommu/vt-d: Don't disable IR when it was previously enabled
  iommu/vt-d: Make sure copied over IR entries are not reused
  iommu/vt-d: Copy IR table from old kernel when in kdump mode
  iommu/vt-d: Set IRTA in intel_setup_irq_remapping
  iommu/vt-d: Disable IRQ remapping in intel_prepare_irq_remapping
  iommu/vt-d: Move QI initializationt to intel_setup_irq_remapping
  iommu/vt-d: Move EIM detection to intel_prepare_irq_remapping
  iommu/vt-d: Enable Translation only if it was previously disabled
  iommu/vt-d: Don't disable translation prior to OS handover
  iommu/vt-d: Don't copy translation tables if RTT bit needs to be changed
  iommu/vt-d: Don't do early domain assignment if kdump kernel
  iommu/vt-d: Allocate si_domain in init_dmars()
  iommu/vt-d: Mark copied context entries
  iommu/vt-d: Do not re-use domain-ids from the old kernel
  iommu/vt-d: Copy translation tables from old kernel
  iommu/vt-d: Detect pre enabled translation
  iommu/vt-d: Make root entry visible for hardware right after allocation
  iommu/vt-d: Init QI before root entry is allocated
  iommu/vt-d: Cleanup log messages
  ...

1 files changed, 158 insertions, 94 deletions

diff --git a/drivers/iommu/intel_irq_remapping.c b/drivers/iommu/intel_irq_remapping.c
index 80f1d1486247..f15692a410c7 100644
--- a/drivers/iommu/intel_irq_remapping.c
+++ b/drivers/iommu/intel_irq_remapping.c
@@ -1,3 +1,6 @@
+
+#define pr_fmt(fmt)     "DMAR-IR: " fmt
+
 #include <linux/interrupt.h>
 #include <linux/dmar.h>
 #include <linux/spinlock.h>
@@ -9,6 +12,7 @@
 #include <linux/intel-iommu.h>
 #include <linux/acpi.h>
 #include <linux/irqdomain.h>
+#include <linux/crash_dump.h>
 #include <asm/io_apic.h>
 #include <asm/smp.h>
 #include <asm/cpu.h>
@@ -74,8 +78,28 @@ static struct hpet_scope ir_hpet[MAX_HPET_TBS];
 static DEFINE_RAW_SPINLOCK(irq_2_ir_lock);
 static struct irq_domain_ops intel_ir_domain_ops;
 
+static void iommu_disable_irq_remapping(struct intel_iommu *iommu);
 static int __init parse_ioapics_under_ir(void);
 
+static bool ir_pre_enabled(struct intel_iommu *iommu)
+{
+	return (iommu->flags & VTD_FLAG_IRQ_REMAP_PRE_ENABLED);
+}
+
+static void clear_ir_pre_enabled(struct intel_iommu *iommu)
+{
+	iommu->flags &= ~VTD_FLAG_IRQ_REMAP_PRE_ENABLED;
+}
+
+static void init_ir_status(struct intel_iommu *iommu)
+{
+	u32 gsts;
+
+	gsts = readl(iommu->reg + DMAR_GSTS_REG);
+	if (gsts & DMA_GSTS_IRES)
+		iommu->flags |= VTD_FLAG_IRQ_REMAP_PRE_ENABLED;
+}
+
 static int alloc_irte(struct intel_iommu *iommu, int irq,
 		      struct irq_2_iommu *irq_iommu, u16 count)
 {
@@ -93,8 +117,7 @@ static int alloc_irte(struct intel_iommu *iommu, int irq,
 	}
 
 	if (mask > ecap_max_handle_mask(iommu->ecap)) {
-		printk(KERN_ERR
-		       "Requested mask %x exceeds the max invalidation handle"
+		pr_err("Requested mask %x exceeds the max invalidation handle"
 		       " mask value %Lx\n", mask,
 		       ecap_max_handle_mask(iommu->ecap));
 		return -1;
@@ -268,7 +291,7 @@ static int set_ioapic_sid(struct irte *irte, int apic)
 	up_read(&dmar_global_lock);
 
 	if (sid == 0) {
-		pr_warning("Failed to set source-id of IOAPIC (%d)\n", apic);
+		pr_warn("Failed to set source-id of IOAPIC (%d)\n", apic);
 		return -1;
 	}
 
@@ -295,7 +318,7 @@ static int set_hpet_sid(struct irte *irte, u8 id)
 	up_read(&dmar_global_lock);
 
 	if (sid == 0) {
-		pr_warning("Failed to set source-id of HPET block (%d)\n", id);
+		pr_warn("Failed to set source-id of HPET block (%d)\n", id);
 		return -1;
 	}
 
@@ -359,11 +382,59 @@ static int set_msi_sid(struct irte *irte, struct pci_dev *dev)
 	return 0;
 }
 
+static int iommu_load_old_irte(struct intel_iommu *iommu)
+{
+	struct irte *old_ir_table;
+	phys_addr_t irt_phys;
+	unsigned int i;
+	size_t size;
+	u64 irta;
+
+	if (!is_kdump_kernel()) {
+		pr_warn("IRQ remapping was enabled on %s but we are not in kdump mode\n",
+			iommu->name);
+		clear_ir_pre_enabled(iommu);
+		iommu_disable_irq_remapping(iommu);
+		return -EINVAL;
+	}
+
+	/* Check whether the old ir-table has the same size as ours */
+	irta = dmar_readq(iommu->reg + DMAR_IRTA_REG);
+	if ((irta & INTR_REMAP_TABLE_REG_SIZE_MASK)
+	     != INTR_REMAP_TABLE_REG_SIZE)
+		return -EINVAL;
+
+	irt_phys = irta & VTD_PAGE_MASK;
+	size     = INTR_REMAP_TABLE_ENTRIES*sizeof(struct irte);
+
+	/* Map the old IR table */
+	old_ir_table = ioremap_cache(irt_phys, size);
+	if (!old_ir_table)
+		return -ENOMEM;
+
+	/* Copy data over */
+	memcpy(iommu->ir_table->base, old_ir_table, size);
+
+	__iommu_flush_cache(iommu, iommu->ir_table->base, size);
+
+	/*
+	 * Now check the table for used entries and mark those as
+	 * allocated in the bitmap
+	 */
+	for (i = 0; i < INTR_REMAP_TABLE_ENTRIES; i++) {
+		if (iommu->ir_table->base[i].present)
+			bitmap_set(iommu->ir_table->bitmap, i, 1);
+	}
+
+	return 0;
+}
+
+
 static void iommu_set_irq_remapping(struct intel_iommu *iommu, int mode)
 {
+	unsigned long flags;
 	u64 addr;
 	u32 sts;
-	unsigned long flags;
 
 	addr = virt_to_phys((void *)iommu->ir_table->base);
 
@@ -380,10 +451,16 @@ static void iommu_set_irq_remapping(struct intel_iommu *iommu, int mode)
 	raw_spin_unlock_irqrestore(&iommu->register_lock, flags);
 
 	/*
-	 * global invalidation of interrupt entry cache before enabling
-	 * interrupt-remapping.
+	 * Global invalidation of interrupt entry cache to make sure the
+	 * hardware uses the new irq remapping table.
 	 */
 	qi_global_iec(iommu);
+}
+
+static void iommu_enable_irq_remapping(struct intel_iommu *iommu)
+{
+	unsigned long flags;
+	u32 sts;
 
 	raw_spin_lock_irqsave(&iommu->register_lock, flags);
 
@@ -449,6 +526,37 @@ static int intel_setup_irq_remapping(struct intel_iommu *iommu)
 	ir_table->base = page_address(pages);
 	ir_table->bitmap = bitmap;
 	iommu->ir_table = ir_table;
+
+	/*
+	 * If the queued invalidation is already initialized,
+	 * shouldn't disable it.
+	 */
+	if (!iommu->qi) {
+		/*
+		 * Clear previous faults.
+		 */
+		dmar_fault(-1, iommu);
+		dmar_disable_qi(iommu);
+
+		if (dmar_enable_qi(iommu)) {
+			pr_err("Failed to enable queued invalidation\n");
+			goto out_free_bitmap;
+		}
+	}
+
+	init_ir_status(iommu);
+
+	if (ir_pre_enabled(iommu)) {
+		if (iommu_load_old_irte(iommu))
+			pr_err("Failed to copy IR table for %s from previous kernel\n",
+			       iommu->name);
+		else
+			pr_info("Copied IR table for %s from previous kernel\n",
+				iommu->name);
+	}
+
+	iommu_set_irq_remapping(iommu, eim_mode);
+
 	return 0;
 
 out_free_bitmap:
@@ -457,6 +565,9 @@ out_free_pages:
 	__free_pages(pages, INTR_REMAP_PAGE_ORDER);
 out_free_table:
 	kfree(ir_table);
+
+	iommu->ir_table  = NULL;
+
 	return -ENOMEM;
 }
 
@@ -534,17 +645,17 @@ static void __init intel_cleanup_irq_remapping(void)
 	}
 
 	if (x2apic_supported())
-		pr_warn("Failed to enable irq remapping.  You are vulnerable to irq-injection attacks.\n");
+		pr_warn("Failed to enable irq remapping. You are vulnerable to irq-injection attacks.\n");
 }
 
 static int __init intel_prepare_irq_remapping(void)
 {
 	struct dmar_drhd_unit *drhd;
 	struct intel_iommu *iommu;
+	int eim = 0;
 
 	if (irq_remap_broken) {
-		printk(KERN_WARNING
-			"This system BIOS has enabled interrupt remapping\n"
+		pr_warn("This system BIOS has enabled interrupt remapping\n"
 			"on a chipset that contains an erratum making that\n"
 			"feature unstable.  To maintain system stability\n"
 			"interrupt remapping is being disabled.  Please\n"
@@ -560,7 +671,7 @@ static int __init intel_prepare_irq_remapping(void)
 		return -ENODEV;
 
 	if (parse_ioapics_under_ir() != 1) {
-		printk(KERN_INFO "Not enabling interrupt remapping\n");
+		pr_info("Not enabling interrupt remapping\n");
 		goto error;
 	}
 
@@ -569,10 +680,34 @@ static int __init intel_prepare_irq_remapping(void)
 		if (!ecap_ir_support(iommu->ecap))
 			goto error;
 
-	/* Do the allocations early */
-	for_each_iommu(iommu, drhd)
-		if (intel_setup_irq_remapping(iommu))
+	/* Detect remapping mode: lapic or x2apic */
+	if (x2apic_supported()) {
+		eim = !dmar_x2apic_optout();
+		if (!eim) {
+			pr_info("x2apic is disabled because BIOS sets x2apic opt out bit.");
+			pr_info("Use 'intremap=no_x2apic_optout' to override the BIOS setting.\n");
+		}
+	}
+
+	for_each_iommu(iommu, drhd) {
+		if (eim && !ecap_eim_support(iommu->ecap)) {
+			pr_info("%s does not support EIM\n", iommu->name);
+			eim = 0;
+		}
+	}
+
+	eim_mode = eim;
+	if (eim)
+		pr_info("Queued invalidation will be enabled to support x2apic and Intr-remapping.\n");
+
+	/* Do the initializations early */
+	for_each_iommu(iommu, drhd) {
+		if (intel_setup_irq_remapping(iommu)) {
+			pr_err("Failed to setup irq remapping for %s\n",
+			       iommu->name);
 			goto error;
+		}
+	}
 
 	return 0;
 
@@ -606,68 +741,13 @@ static int __init intel_enable_irq_remapping(void)
 	struct dmar_drhd_unit *drhd;
 	struct intel_iommu *iommu;
 	bool setup = false;
-	int eim = 0;
-
-	if (x2apic_supported()) {
-		eim = !dmar_x2apic_optout();
-		if (!eim)
-			pr_info("x2apic is disabled because BIOS sets x2apic opt out bit. You can use 'intremap=no_x2apic_optout' to override the BIOS setting.\n");
-	}
-
-	for_each_iommu(iommu, drhd) {
-		/*
-		 * If the queued invalidation is already initialized,
-		 * shouldn't disable it.
-		 */
-		if (iommu->qi)
-			continue;
-
-		/*
-		 * Clear previous faults.
-		 */
-		dmar_fault(-1, iommu);
-
-		/*
-		 * Disable intr remapping and queued invalidation, if already
-		 * enabled prior to OS handover.
-		 */
-		iommu_disable_irq_remapping(iommu);
-
-		dmar_disable_qi(iommu);
-	}
-
-	/*
-	 * check for the Interrupt-remapping support
-	 */
-	for_each_iommu(iommu, drhd)
-		if (eim && !ecap_eim_support(iommu->ecap)) {
-			printk(KERN_INFO "DRHD %Lx: EIM not supported by DRHD, "
-			       " ecap %Lx\n", drhd->reg_base_addr, iommu->ecap);
-			eim = 0;
-		}
-	eim_mode = eim;
-	if (eim)
-		pr_info("Queued invalidation will be enabled to support x2apic and Intr-remapping.\n");
-
-	/*
-	 * Enable queued invalidation for all the DRHD's.
-	 */
-	for_each_iommu(iommu, drhd) {
-		int ret = dmar_enable_qi(iommu);
-
-		if (ret) {
-			printk(KERN_ERR "DRHD %Lx: failed to enable queued, "
-			       " invalidation, ecap %Lx, ret %d\n",
-			       drhd->reg_base_addr, iommu->ecap, ret);
-			goto error;
-		}
-	}
 
 	/*
 	 * Setup Interrupt-remapping for all the DRHD's now.
 	 */
 	for_each_iommu(iommu, drhd) {
-		iommu_set_irq_remapping(iommu, eim);
+		if (!ir_pre_enabled(iommu))
+			iommu_enable_irq_remapping(iommu);
 		setup = true;
 	}
 
@@ -678,9 +758,9 @@ static int __init intel_enable_irq_remapping(void)
 
 	set_irq_posting_cap();
 
-	pr_info("Enabled IRQ remapping in %s mode\n", eim ? "x2apic" : "xapic");
+	pr_info("Enabled IRQ remapping in %s mode\n", eim_mode ? "x2apic" : "xapic");
 
-	return eim ? IRQ_REMAP_X2APIC_MODE : IRQ_REMAP_XAPIC_MODE;
+	return eim_mode ? IRQ_REMAP_X2APIC_MODE : IRQ_REMAP_XAPIC_MODE;
 
 error:
 	intel_cleanup_irq_remapping();
@@ -905,6 +985,7 @@ static int reenable_irq_remapping(int eim)
 
 		/* Set up interrupt remapping for iommu.*/
 		iommu_set_irq_remapping(iommu, eim);
+		iommu_enable_irq_remapping(iommu);
 		setup = true;
 	}
 
@@ -1169,7 +1250,6 @@ static void intel_free_irq_resources(struct irq_domain *domain,
 	struct irq_2_iommu *irq_iommu;
 	unsigned long flags;
 	int i;
-
 	for (i = 0; i < nr_irqs; i++) {
 		irq_data = irq_domain_get_irq_data(domain, virq  + i);
 		if (irq_data && irq_data->chip_data) {
@@ -1317,28 +1397,12 @@ static int dmar_ir_add(struct dmar_drhd_unit *dmaru, struct intel_iommu *iommu)
 	/* Setup Interrupt-remapping now. */
 	ret = intel_setup_irq_remapping(iommu);
 	if (ret) {
-		pr_err("DRHD %Lx: failed to allocate resource\n",
-		       iommu->reg_phys);
-		ir_remove_ioapic_hpet_scope(iommu);
-		return ret;
-	}
-
-	if (!iommu->qi) {
-		/* Clear previous faults. */
-		dmar_fault(-1, iommu);
-		iommu_disable_irq_remapping(iommu);
-		dmar_disable_qi(iommu);
-	}
-
-	/* Enable queued invalidation */
-	ret = dmar_enable_qi(iommu);
-	if (!ret) {
-		iommu_set_irq_remapping(iommu, eim);
-	} else {
-		pr_err("DRHD %Lx: failed to enable queued invalidation, ecap %Lx, ret %d\n",
-		       iommu->reg_phys, iommu->ecap, ret);
+		pr_err("Failed to setup irq remapping for %s\n",
+		       iommu->name);
 		intel_teardown_irq_remapping(iommu);
 		ir_remove_ioapic_hpet_scope(iommu);
+	} else {
+		iommu_enable_irq_remapping(iommu);
 	}
 
 	return ret;